drivers/regulator/core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 //
   3 // core.c  --  Voltage/Current Regulator framework.
   4 //
   5 // Copyright 2007, 2008 Wolfson Microelectronics PLC.
   6 // Copyright 2008 SlimLogic Ltd.
   7 //
   8 // Author: Liam Girdwood <lrg@slimlogic.co.uk>
   9
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/device.h>
  14 #include <linux/slab.h>
  15 #include <linux/async.h>
  16 #include <linux/err.h>
  17 #include <linux/mutex.h>
  18 #include <linux/suspend.h>
  19 #include <linux/delay.h>
  20 #include <linux/gpio/consumer.h>
  21 #include <linux/of.h>
  22 #include <linux/reboot.h>
  23 #include <linux/regmap.h>
  24 #include <linux/regulator/of_regulator.h>
  25 #include <linux/regulator/consumer.h>
  26 #include <linux/regulator/coupler.h>
  27 #include <linux/regulator/driver.h>
  28 #include <linux/regulator/machine.h>
  29 #include <linux/module.h>
  30
  31 #define CREATE_TRACE_POINTS
  32 #include <trace/events/regulator.h>
  33
  34 #include "dummy.h"
  35 #include "internal.h"
  36 #include "regnl.h"
  37
  38 static DEFINE_WW_CLASS(regulator_ww_class);
  39 static DEFINE_MUTEX(regulator_nesting_mutex);
  40 static DEFINE_MUTEX(regulator_list_mutex);
  41 static LIST_HEAD(regulator_map_list);
  42 static LIST_HEAD(regulator_ena_gpio_list);
  43 static LIST_HEAD(regulator_supply_alias_list);
  44 static LIST_HEAD(regulator_coupler_list);
  45 static bool has_full_constraints;
  46
  47 static struct dentry *debugfs_root;
  48
  49 /*
  50  * struct regulator_map
  51  *
  52  * Used to provide symbolic supply names to devices.
  53  */
  54 struct regulator_map {
  55         struct list_head list;
  56         const char *dev_name;   /* The dev_name() for the consumer */
  57         const char *supply;
  58         struct regulator_dev *regulator;
  59 };
  60
  61 /*
  62  * struct regulator_enable_gpio
  63  *
  64  * Management for shared enable GPIO pin
  65  */
  66 struct regulator_enable_gpio {
  67         struct list_head list;
  68         struct gpio_desc *gpiod;
  69         u32 enable_count;       /* a number of enabled shared GPIO */
  70         u32 request_count;      /* a number of requested shared GPIO */
  71 };
  72
  73 /*
  74  * struct regulator_supply_alias
  75  *
  76  * Used to map lookups for a supply onto an alternative device.
  77  */
  78 struct regulator_supply_alias {
  79         struct list_head list;
  80         struct device *src_dev;
  81         const char *src_supply;
  82         struct device *alias_dev;
  83         const char *alias_supply;
  84 };
  85
  86 static int _regulator_is_enabled(struct regulator_dev *rdev);
  87 static int _regulator_disable(struct regulator *regulator);
  88 static int _regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags);
  89 static int _regulator_get_current_limit(struct regulator_dev *rdev);
  90 static unsigned int _regulator_get_mode(struct regulator_dev *rdev);
  91 static int _notifier_call_chain(struct regulator_dev *rdev,
  92                                   unsigned long event, void *data);
  93 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
  94                                      int min_uV, int max_uV);
  95 static int regulator_balance_voltage(struct regulator_dev *rdev,
  96                                      suspend_state_t state);
  97 static struct regulator *create_regulator(struct regulator_dev *rdev,
  98                                           struct device *dev,
  99                                           const char *supply_name);
 100 static void destroy_regulator(struct regulator *regulator);
 101 static void _regulator_put(struct regulator *regulator);
 102
 103 const char *rdev_get_name(struct regulator_dev *rdev)
 104 {
 105         if (rdev->constraints && rdev->constraints->name)
 106                 return rdev->constraints->name;
 107         else if (rdev->desc->name)
 108                 return rdev->desc->name;
 109         else
 110                 return "";
 111 }
 112 EXPORT_SYMBOL_GPL(rdev_get_name);
 113
 114 static bool have_full_constraints(void)
 115 {
 116         return has_full_constraints || of_have_populated_dt();
 117 }
 118
 119 static bool regulator_ops_is_valid(struct regulator_dev *rdev, int ops)
 120 {
 121         if (!rdev->constraints) {
 122                 rdev_err(rdev, "no constraints\n");
 123                 return false;
 124         }
 125
 126         if (rdev->constraints->valid_ops_mask & ops)
 127                 return true;
 128
 129         return false;
 130 }
 131
 132 /**
 133  * regulator_lock_nested - lock a single regulator
 134  * @rdev:               regulator source
 135  * @ww_ctx:             w/w mutex acquire context
 136  *
 137  * This function can be called many times by one task on
 138  * a single regulator and its mutex will be locked only
 139  * once. If a task, which is calling this function is other
 140  * than the one, which initially locked the mutex, it will
 141  * wait on mutex.
 142  */
 143 static inline int regulator_lock_nested(struct regulator_dev *rdev,
 144                                         struct ww_acquire_ctx *ww_ctx)
 145 {
 146         bool lock = false;
 147         int ret = 0;
 148
 149         mutex_lock(&regulator_nesting_mutex);
 150
 151         if (!ww_mutex_trylock(&rdev->mutex, ww_ctx)) {
 152                 if (rdev->mutex_owner == current)
 153                         rdev->ref_cnt++;
 154                 else
 155                         lock = true;
 156
 157                 if (lock) {
 158                         mutex_unlock(&regulator_nesting_mutex);
 159                         ret = ww_mutex_lock(&rdev->mutex, ww_ctx);
 160                         mutex_lock(&regulator_nesting_mutex);
 161                 }
 162         } else {
 163                 lock = true;
 164         }
 165
 166         if (lock && ret != -EDEADLK) {
 167                 rdev->ref_cnt++;
 168                 rdev->mutex_owner = current;
 169         }
 170
 171         mutex_unlock(&regulator_nesting_mutex);
 172
 173         return ret;
 174 }
 175
 176 /**
 177  * regulator_lock - lock a single regulator
 178  * @rdev:               regulator source
 179  *
 180  * This function can be called many times by one task on
 181  * a single regulator and its mutex will be locked only
 182  * once. If a task, which is calling this function is other
 183  * than the one, which initially locked the mutex, it will
 184  * wait on mutex.
 185  */
 186 static void regulator_lock(struct regulator_dev *rdev)
 187 {
 188         regulator_lock_nested(rdev, NULL);
 189 }
 190
 191 /**
 192  * regulator_unlock - unlock a single regulator
 193  * @rdev:               regulator_source
 194  *
 195  * This function unlocks the mutex when the
 196  * reference counter reaches 0.
 197  */
 198 static void regulator_unlock(struct regulator_dev *rdev)
 199 {
 200         mutex_lock(&regulator_nesting_mutex);
 201
 202         if (--rdev->ref_cnt == 0) {
 203                 rdev->mutex_owner = NULL;
 204                 ww_mutex_unlock(&rdev->mutex);
 205         }
 206
 207         WARN_ON_ONCE(rdev->ref_cnt < 0);
 208
 209         mutex_unlock(&regulator_nesting_mutex);
 210 }
 211
 212 /**
 213  * regulator_lock_two - lock two regulators
 214  * @rdev1:              first regulator
 215  * @rdev2:              second regulator
 216  * @ww_ctx:             w/w mutex acquire context
 217  *
 218  * Locks both rdevs using the regulator_ww_class.
 219  */
 220 static void regulator_lock_two(struct regulator_dev *rdev1,
 221                                struct regulator_dev *rdev2,
 222                                struct ww_acquire_ctx *ww_ctx)
 223 {
 224         struct regulator_dev *held, *contended;
 225         int ret;
 226
 227         ww_acquire_init(ww_ctx, &regulator_ww_class);
 228
 229         /* Try to just grab both of them */
 230         ret = regulator_lock_nested(rdev1, ww_ctx);
 231         WARN_ON(ret);
 232         ret = regulator_lock_nested(rdev2, ww_ctx);
 233         if (ret != -EDEADLOCK) {
 234                 WARN_ON(ret);
 235                 goto exit;
 236         }
 237
 238         held = rdev1;
 239         contended = rdev2;
 240         while (true) {
 241                 regulator_unlock(held);
 242
 243                 ww_mutex_lock_slow(&contended->mutex, ww_ctx);
 244                 contended->ref_cnt++;
 245                 contended->mutex_owner = current;
 246                 swap(held, contended);
 247                 ret = regulator_lock_nested(contended, ww_ctx);
 248
 249                 if (ret != -EDEADLOCK) {
 250                         WARN_ON(ret);
 251                         break;
 252                 }
 253         }
 254
 255 exit:
 256         ww_acquire_done(ww_ctx);
 257 }
 258
 259 /**
 260  * regulator_unlock_two - unlock two regulators
 261  * @rdev1:              first regulator
 262  * @rdev2:              second regulator
 263  * @ww_ctx:             w/w mutex acquire context
 264  *
 265  * The inverse of regulator_lock_two().
 266  */
 267
 268 static void regulator_unlock_two(struct regulator_dev *rdev1,
 269                                  struct regulator_dev *rdev2,
 270                                  struct ww_acquire_ctx *ww_ctx)
 271 {
 272         regulator_unlock(rdev2);
 273         regulator_unlock(rdev1);
 274         ww_acquire_fini(ww_ctx);
 275 }
 276
 277 static bool regulator_supply_is_couple(struct regulator_dev *rdev)
 278 {
 279         struct regulator_dev *c_rdev;
 280         int i;
 281
 282         for (i = 1; i < rdev->coupling_desc.n_coupled; i++) {
 283                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 284
 285                 if (rdev->supply->rdev == c_rdev)
 286                         return true;
 287         }
 288
 289         return false;
 290 }
 291
 292 static void regulator_unlock_recursive(struct regulator_dev *rdev,
 293                                        unsigned int n_coupled)
 294 {
 295         struct regulator_dev *c_rdev, *supply_rdev;
 296         int i, supply_n_coupled;
 297
 298         for (i = n_coupled; i > 0; i--) {
 299                 c_rdev = rdev->coupling_desc.coupled_rdevs[i - 1];
 300
 301                 if (!c_rdev)
 302                         continue;
 303
 304                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 305                         supply_rdev = c_rdev->supply->rdev;
 306                         supply_n_coupled = supply_rdev->coupling_desc.n_coupled;
 307
 308                         regulator_unlock_recursive(supply_rdev,
 309                                                    supply_n_coupled);
 310                 }
 311
 312                 regulator_unlock(c_rdev);
 313         }
 314 }
 315
 316 static int regulator_lock_recursive(struct regulator_dev *rdev,
 317                                     struct regulator_dev **new_contended_rdev,
 318                                     struct regulator_dev **old_contended_rdev,
 319                                     struct ww_acquire_ctx *ww_ctx)
 320 {
 321         struct regulator_dev *c_rdev;
 322         int i, err;
 323
 324         for (i = 0; i < rdev->coupling_desc.n_coupled; i++) {
 325                 c_rdev = rdev->coupling_desc.coupled_rdevs[i];
 326
 327                 if (!c_rdev)
 328                         continue;
 329
 330                 if (c_rdev != *old_contended_rdev) {
 331                         err = regulator_lock_nested(c_rdev, ww_ctx);
 332                         if (err) {
 333                                 if (err == -EDEADLK) {
 334                                         *new_contended_rdev = c_rdev;
 335                                         goto err_unlock;
 336                                 }
 337
 338                                 /* shouldn't happen */
 339                                 WARN_ON_ONCE(err != -EALREADY);
 340                         }
 341                 } else {
 342                         *old_contended_rdev = NULL;
 343                 }
 344
 345                 if (c_rdev->supply && !regulator_supply_is_couple(c_rdev)) {
 346                         err = regulator_lock_recursive(c_rdev->supply->rdev,
 347                                                        new_contended_rdev,
 348                                                        old_contended_rdev,
 349                                                        ww_ctx);
 350                         if (err) {
 351                                 regulator_unlock(c_rdev);
 352                                 goto err_unlock;
 353                         }
 354                 }
 355         }
 356
 357         return 0;
 358
 359 err_unlock:
 360         regulator_unlock_recursive(rdev, i);
 361
 362         return err;
 363 }
 364
 365 /**
 366  * regulator_unlock_dependent - unlock regulator's suppliers and coupled
 367  *                              regulators
 368  * @rdev:                       regulator source
 369  * @ww_ctx:                     w/w mutex acquire context
 370  *
 371  * Unlock all regulators related with rdev by coupling or supplying.
 372  */
 373 static void regulator_unlock_dependent(struct regulator_dev *rdev,
 374                                        struct ww_acquire_ctx *ww_ctx)
 375 {
 376         regulator_unlock_recursive(rdev, rdev->coupling_desc.n_coupled);
 377         ww_acquire_fini(ww_ctx);
 378 }
 379
 380 /**
 381  * regulator_lock_dependent - lock regulator's suppliers and coupled regulators
 382  * @rdev:                       regulator source
 383  * @ww_ctx:                     w/w mutex acquire context
 384  *
 385  * This function as a wrapper on regulator_lock_recursive(), which locks
 386  * all regulators related with rdev by coupling or supplying.
 387  */
 388 static void regulator_lock_dependent(struct regulator_dev *rdev,
 389                                      struct ww_acquire_ctx *ww_ctx)
 390 {
 391         struct regulator_dev *new_contended_rdev = NULL;
 392         struct regulator_dev *old_contended_rdev = NULL;
 393         int err;
 394
 395         mutex_lock(&regulator_list_mutex);
 396
 397         ww_acquire_init(ww_ctx, &regulator_ww_class);
 398
 399         do {
 400                 if (new_contended_rdev) {
 401                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
 402                         old_contended_rdev = new_contended_rdev;
 403                         old_contended_rdev->ref_cnt++;
 404                         old_contended_rdev->mutex_owner = current;
 405                 }
 406
 407                 err = regulator_lock_recursive(rdev,
 408                                                &new_contended_rdev,
 409                                                &old_contended_rdev,
 410                                                ww_ctx);
 411
 412                 if (old_contended_rdev)
 413                         regulator_unlock(old_contended_rdev);
 414
 415         } while (err == -EDEADLK);
 416
 417         ww_acquire_done(ww_ctx);
 418
 419         mutex_unlock(&regulator_list_mutex);
 420 }
 421
 422 /**
 423  * of_get_child_regulator - get a child regulator device node
 424  * based on supply name
 425  * @parent: Parent device node
 426  * @prop_name: Combination regulator supply name and "-supply"
 427  *
 428  * Traverse all child nodes.
 429  * Extract the child regulator device node corresponding to the supply name.
 430  * returns the device node corresponding to the regulator if found, else
 431  * returns NULL.
 432  */
 433 static struct device_node *of_get_child_regulator(struct device_node *parent,
 434                                                   const char *prop_name)
 435 {
 436         struct device_node *regnode = NULL;
 437         struct device_node *child = NULL;
 438
 439         for_each_child_of_node(parent, child) {
 440                 regnode = of_parse_phandle(child, prop_name, 0);
 441
 442                 if (!regnode) {
 443                         regnode = of_get_child_regulator(child, prop_name);
 444                         if (regnode)
 445                                 goto err_node_put;
 446                 } else {
 447                         goto err_node_put;
 448                 }
 449         }
 450         return NULL;
 451
 452 err_node_put:
 453         of_node_put(child);
 454         return regnode;
 455 }
 456
 457 /**
 458  * of_get_regulator - get a regulator device node based on supply name
 459  * @dev: Device pointer for the consumer (of regulator) device
 460  * @supply: regulator supply name
 461  *
 462  * Extract the regulator device node corresponding to the supply name.
 463  * returns the device node corresponding to the regulator if found, else
 464  * returns NULL.
 465  */
 466 static struct device_node *of_get_regulator(struct device *dev, const char *supply)
 467 {
 468         struct device_node *regnode = NULL;
 469         char prop_name[64]; /* 64 is max size of property name */
 470
 471         dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);
 472
 473         snprintf(prop_name, 64, "%s-supply", supply);
 474         regnode = of_parse_phandle(dev->of_node, prop_name, 0);
 475
 476         if (!regnode) {
 477                 regnode = of_get_child_regulator(dev->of_node, prop_name);
 478                 if (regnode)
 479                         return regnode;
 480
 481                 dev_dbg(dev, "Looking up %s property in node %pOF failed\n",
 482                                 prop_name, dev->of_node);
 483                 return NULL;
 484         }
 485         return regnode;
 486 }
 487
 488 /* Platform voltage constraint check */
 489 int regulator_check_voltage(struct regulator_dev *rdev,
 490                             int *min_uV, int *max_uV)
 491 {
 492         BUG_ON(*min_uV > *max_uV);
 493
 494         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
 495                 rdev_err(rdev, "voltage operation not allowed\n");
 496                 return -EPERM;
 497         }
 498
 499         if (*max_uV > rdev->constraints->max_uV)
 500                 *max_uV = rdev->constraints->max_uV;
 501         if (*min_uV < rdev->constraints->min_uV)
 502                 *min_uV = rdev->constraints->min_uV;
 503
 504         if (*min_uV > *max_uV) {
 505                 rdev_err(rdev, "unsupportable voltage range: %d-%duV\n",
 506                          *min_uV, *max_uV);
 507                 return -EINVAL;
 508         }
 509
 510         return 0;
 511 }
 512
 513 /* return 0 if the state is valid */
 514 static int regulator_check_states(suspend_state_t state)
 515 {
 516         return (state > PM_SUSPEND_MAX || state == PM_SUSPEND_TO_IDLE);
 517 }
 518
 519 /* Make sure we select a voltage that suits the needs of all
 520  * regulator consumers
 521  */
 522 int regulator_check_consumers(struct regulator_dev *rdev,
 523                               int *min_uV, int *max_uV,
 524                               suspend_state_t state)
 525 {
 526         struct regulator *regulator;
 527         struct regulator_voltage *voltage;
 528
 529         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 530                 voltage = &regulator->voltage[state];
 531                 /*
 532                  * Assume consumers that didn't say anything are OK
 533                  * with anything in the constraint range.
 534                  */
 535                 if (!voltage->min_uV && !voltage->max_uV)
 536                         continue;
 537
 538                 if (*max_uV > voltage->max_uV)
 539                         *max_uV = voltage->max_uV;
 540                 if (*min_uV < voltage->min_uV)
 541                         *min_uV = voltage->min_uV;
 542         }
 543
 544         if (*min_uV > *max_uV) {
 545                 rdev_err(rdev, "Restricting voltage, %u-%uuV\n",
 546                         *min_uV, *max_uV);
 547                 return -EINVAL;
 548         }
 549
 550         return 0;
 551 }
 552
 553 /* current constraint check */
 554 static int regulator_check_current_limit(struct regulator_dev *rdev,
 555                                         int *min_uA, int *max_uA)
 556 {
 557         BUG_ON(*min_uA > *max_uA);
 558
 559         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_CURRENT)) {
 560                 rdev_err(rdev, "current operation not allowed\n");
 561                 return -EPERM;
 562         }
 563
 564         if (*max_uA > rdev->constraints->max_uA)
 565                 *max_uA = rdev->constraints->max_uA;
 566         if (*min_uA < rdev->constraints->min_uA)
 567                 *min_uA = rdev->constraints->min_uA;
 568
 569         if (*min_uA > *max_uA) {
 570                 rdev_err(rdev, "unsupportable current range: %d-%duA\n",
 571                          *min_uA, *max_uA);
 572                 return -EINVAL;
 573         }
 574
 575         return 0;
 576 }
 577
 578 /* operating mode constraint check */
 579 static int regulator_mode_constrain(struct regulator_dev *rdev,
 580                                     unsigned int *mode)
 581 {
 582         switch (*mode) {
 583         case REGULATOR_MODE_FAST:
 584         case REGULATOR_MODE_NORMAL:
 585         case REGULATOR_MODE_IDLE:
 586         case REGULATOR_MODE_STANDBY:
 587                 break;
 588         default:
 589                 rdev_err(rdev, "invalid mode %x specified\n", *mode);
 590                 return -EINVAL;
 591         }
 592
 593         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_MODE)) {
 594                 rdev_err(rdev, "mode operation not allowed\n");
 595                 return -EPERM;
 596         }
 597
 598         /* The modes are bitmasks, the most power hungry modes having
 599          * the lowest values. If the requested mode isn't supported
 600          * try higher modes.
 601          */
 602         while (*mode) {
 603                 if (rdev->constraints->valid_modes_mask & *mode)
 604                         return 0;
 605                 *mode /= 2;
 606         }
 607
 608         return -EINVAL;
 609 }
 610
 611 static inline struct regulator_state *
 612 regulator_get_suspend_state(struct regulator_dev *rdev, suspend_state_t state)
 613 {
 614         if (rdev->constraints == NULL)
 615                 return NULL;
 616
 617         switch (state) {
 618         case PM_SUSPEND_STANDBY:
 619                 return &rdev->constraints->state_standby;
 620         case PM_SUSPEND_MEM:
 621                 return &rdev->constraints->state_mem;
 622         case PM_SUSPEND_MAX:
 623                 return &rdev->constraints->state_disk;
 624         default:
 625                 return NULL;
 626         }
 627 }
 628
 629 static const struct regulator_state *
 630 regulator_get_suspend_state_check(struct regulator_dev *rdev, suspend_state_t state)
 631 {
 632         const struct regulator_state *rstate;
 633
 634         rstate = regulator_get_suspend_state(rdev, state);
 635         if (rstate == NULL)
 636                 return NULL;
 637
 638         /* If we have no suspend mode configuration don't set anything;
 639          * only warn if the driver implements set_suspend_voltage or
 640          * set_suspend_mode callback.
 641          */
 642         if (rstate->enabled != ENABLE_IN_SUSPEND &&
 643             rstate->enabled != DISABLE_IN_SUSPEND) {
 644                 if (rdev->desc->ops->set_suspend_voltage ||
 645                     rdev->desc->ops->set_suspend_mode)
 646                         rdev_warn(rdev, "No configuration\n");
 647                 return NULL;
 648         }
 649
 650         return rstate;
 651 }
 652
 653 static ssize_t microvolts_show(struct device *dev,
 654                                struct device_attribute *attr, char *buf)
 655 {
 656         struct regulator_dev *rdev = dev_get_drvdata(dev);
 657         int uV;
 658
 659         regulator_lock(rdev);
 660         uV = regulator_get_voltage_rdev(rdev);
 661         regulator_unlock(rdev);
 662
 663         if (uV < 0)
 664                 return uV;
 665         return sprintf(buf, "%d\n", uV);
 666 }
 667 static DEVICE_ATTR_RO(microvolts);
 668
 669 static ssize_t microamps_show(struct device *dev,
 670                               struct device_attribute *attr, char *buf)
 671 {
 672         struct regulator_dev *rdev = dev_get_drvdata(dev);
 673
 674         return sprintf(buf, "%d\n", _regulator_get_current_limit(rdev));
 675 }
 676 static DEVICE_ATTR_RO(microamps);
 677
 678 static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 679                          char *buf)
 680 {
 681         struct regulator_dev *rdev = dev_get_drvdata(dev);
 682
 683         return sprintf(buf, "%s\n", rdev_get_name(rdev));
 684 }
 685 static DEVICE_ATTR_RO(name);
 686
 687 static const char *regulator_opmode_to_str(int mode)
 688 {
 689         switch (mode) {
 690         case REGULATOR_MODE_FAST:
 691                 return "fast";
 692         case REGULATOR_MODE_NORMAL:
 693                 return "normal";
 694         case REGULATOR_MODE_IDLE:
 695                 return "idle";
 696         case REGULATOR_MODE_STANDBY:
 697                 return "standby";
 698         }
 699         return "unknown";
 700 }
 701
 702 static ssize_t regulator_print_opmode(char *buf, int mode)
 703 {
 704         return sprintf(buf, "%s\n", regulator_opmode_to_str(mode));
 705 }
 706
 707 static ssize_t opmode_show(struct device *dev,
 708                            struct device_attribute *attr, char *buf)
 709 {
 710         struct regulator_dev *rdev = dev_get_drvdata(dev);
 711
 712         return regulator_print_opmode(buf, _regulator_get_mode(rdev));
 713 }
 714 static DEVICE_ATTR_RO(opmode);
 715
 716 static ssize_t regulator_print_state(char *buf, int state)
 717 {
 718         if (state > 0)
 719                 return sprintf(buf, "enabled\n");
 720         else if (state == 0)
 721                 return sprintf(buf, "disabled\n");
 722         else
 723                 return sprintf(buf, "unknown\n");
 724 }
 725
 726 static ssize_t state_show(struct device *dev,
 727                           struct device_attribute *attr, char *buf)
 728 {
 729         struct regulator_dev *rdev = dev_get_drvdata(dev);
 730         ssize_t ret;
 731
 732         regulator_lock(rdev);
 733         ret = regulator_print_state(buf, _regulator_is_enabled(rdev));
 734         regulator_unlock(rdev);
 735
 736         return ret;
 737 }
 738 static DEVICE_ATTR_RO(state);
 739
 740 static ssize_t status_show(struct device *dev,
 741                            struct device_attribute *attr, char *buf)
 742 {
 743         struct regulator_dev *rdev = dev_get_drvdata(dev);
 744         int status;
 745         char *label;
 746
 747         status = rdev->desc->ops->get_status(rdev);
 748         if (status < 0)
 749                 return status;
 750
 751         switch (status) {
 752         case REGULATOR_STATUS_OFF:
 753                 label = "off";
 754                 break;
 755         case REGULATOR_STATUS_ON:
 756                 label = "on";
 757                 break;
 758         case REGULATOR_STATUS_ERROR:
 759                 label = "error";
 760                 break;
 761         case REGULATOR_STATUS_FAST:
 762                 label = "fast";
 763                 break;
 764         case REGULATOR_STATUS_NORMAL:
 765                 label = "normal";
 766                 break;
 767         case REGULATOR_STATUS_IDLE:
 768                 label = "idle";
 769                 break;
 770         case REGULATOR_STATUS_STANDBY:
 771                 label = "standby";
 772                 break;
 773         case REGULATOR_STATUS_BYPASS:
 774                 label = "bypass";
 775                 break;
 776         case REGULATOR_STATUS_UNDEFINED:
 777                 label = "undefined";
 778                 break;
 779         default:
 780                 return -ERANGE;
 781         }
 782
 783         return sprintf(buf, "%s\n", label);
 784 }
 785 static DEVICE_ATTR_RO(status);
 786
 787 static ssize_t min_microamps_show(struct device *dev,
 788                                   struct device_attribute *attr, char *buf)
 789 {
 790         struct regulator_dev *rdev = dev_get_drvdata(dev);
 791
 792         if (!rdev->constraints)
 793                 return sprintf(buf, "constraint not defined\n");
 794
 795         return sprintf(buf, "%d\n", rdev->constraints->min_uA);
 796 }
 797 static DEVICE_ATTR_RO(min_microamps);
 798
 799 static ssize_t max_microamps_show(struct device *dev,
 800                                   struct device_attribute *attr, char *buf)
 801 {
 802         struct regulator_dev *rdev = dev_get_drvdata(dev);
 803
 804         if (!rdev->constraints)
 805                 return sprintf(buf, "constraint not defined\n");
 806
 807         return sprintf(buf, "%d\n", rdev->constraints->max_uA);
 808 }
 809 static DEVICE_ATTR_RO(max_microamps);
 810
 811 static ssize_t min_microvolts_show(struct device *dev,
 812                                    struct device_attribute *attr, char *buf)
 813 {
 814         struct regulator_dev *rdev = dev_get_drvdata(dev);
 815
 816         if (!rdev->constraints)
 817                 return sprintf(buf, "constraint not defined\n");
 818
 819         return sprintf(buf, "%d\n", rdev->constraints->min_uV);
 820 }
 821 static DEVICE_ATTR_RO(min_microvolts);
 822
 823 static ssize_t max_microvolts_show(struct device *dev,
 824                                    struct device_attribute *attr, char *buf)
 825 {
 826         struct regulator_dev *rdev = dev_get_drvdata(dev);
 827
 828         if (!rdev->constraints)
 829                 return sprintf(buf, "constraint not defined\n");
 830
 831         return sprintf(buf, "%d\n", rdev->constraints->max_uV);
 832 }
 833 static DEVICE_ATTR_RO(max_microvolts);
 834
 835 static ssize_t requested_microamps_show(struct device *dev,
 836                                         struct device_attribute *attr, char *buf)
 837 {
 838         struct regulator_dev *rdev = dev_get_drvdata(dev);
 839         struct regulator *regulator;
 840         int uA = 0;
 841
 842         regulator_lock(rdev);
 843         list_for_each_entry(regulator, &rdev->consumer_list, list) {
 844                 if (regulator->enable_count)
 845                         uA += regulator->uA_load;
 846         }
 847         regulator_unlock(rdev);
 848         return sprintf(buf, "%d\n", uA);
 849 }
 850 static DEVICE_ATTR_RO(requested_microamps);
 851
 852 static ssize_t num_users_show(struct device *dev, struct device_attribute *attr,
 853                               char *buf)
 854 {
 855         struct regulator_dev *rdev = dev_get_drvdata(dev);
 856         return sprintf(buf, "%d\n", rdev->use_count);
 857 }
 858 static DEVICE_ATTR_RO(num_users);
 859
 860 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
 861                          char *buf)
 862 {
 863         struct regulator_dev *rdev = dev_get_drvdata(dev);
 864
 865         switch (rdev->desc->type) {
 866         case REGULATOR_VOLTAGE:
 867                 return sprintf(buf, "voltage\n");
 868         case REGULATOR_CURRENT:
 869                 return sprintf(buf, "current\n");
 870         }
 871         return sprintf(buf, "unknown\n");
 872 }
 873 static DEVICE_ATTR_RO(type);
 874
 875 static ssize_t suspend_mem_microvolts_show(struct device *dev,
 876                                            struct device_attribute *attr, char *buf)
 877 {
 878         struct regulator_dev *rdev = dev_get_drvdata(dev);
 879
 880         return sprintf(buf, "%d\n", rdev->constraints->state_mem.uV);
 881 }
 882 static DEVICE_ATTR_RO(suspend_mem_microvolts);
 883
 884 static ssize_t suspend_disk_microvolts_show(struct device *dev,
 885                                             struct device_attribute *attr, char *buf)
 886 {
 887         struct regulator_dev *rdev = dev_get_drvdata(dev);
 888
 889         return sprintf(buf, "%d\n", rdev->constraints->state_disk.uV);
 890 }
 891 static DEVICE_ATTR_RO(suspend_disk_microvolts);
 892
 893 static ssize_t suspend_standby_microvolts_show(struct device *dev,
 894                                                struct device_attribute *attr, char *buf)
 895 {
 896         struct regulator_dev *rdev = dev_get_drvdata(dev);
 897
 898         return sprintf(buf, "%d\n", rdev->constraints->state_standby.uV);
 899 }
 900 static DEVICE_ATTR_RO(suspend_standby_microvolts);
 901
 902 static ssize_t suspend_mem_mode_show(struct device *dev,
 903                                      struct device_attribute *attr, char *buf)
 904 {
 905         struct regulator_dev *rdev = dev_get_drvdata(dev);
 906
 907         return regulator_print_opmode(buf,
 908                 rdev->constraints->state_mem.mode);
 909 }
 910 static DEVICE_ATTR_RO(suspend_mem_mode);
 911
 912 static ssize_t suspend_disk_mode_show(struct device *dev,
 913                                       struct device_attribute *attr, char *buf)
 914 {
 915         struct regulator_dev *rdev = dev_get_drvdata(dev);
 916
 917         return regulator_print_opmode(buf,
 918                 rdev->constraints->state_disk.mode);
 919 }
 920 static DEVICE_ATTR_RO(suspend_disk_mode);
 921
 922 static ssize_t suspend_standby_mode_show(struct device *dev,
 923                                          struct device_attribute *attr, char *buf)
 924 {
 925         struct regulator_dev *rdev = dev_get_drvdata(dev);
 926
 927         return regulator_print_opmode(buf,
 928                 rdev->constraints->state_standby.mode);
 929 }
 930 static DEVICE_ATTR_RO(suspend_standby_mode);
 931
 932 static ssize_t suspend_mem_state_show(struct device *dev,
 933                                       struct device_attribute *attr, char *buf)
 934 {
 935         struct regulator_dev *rdev = dev_get_drvdata(dev);
 936
 937         return regulator_print_state(buf,
 938                         rdev->constraints->state_mem.enabled);
 939 }
 940 static DEVICE_ATTR_RO(suspend_mem_state);
 941
 942 static ssize_t suspend_disk_state_show(struct device *dev,
 943                                        struct device_attribute *attr, char *buf)
 944 {
 945         struct regulator_dev *rdev = dev_get_drvdata(dev);
 946
 947         return regulator_print_state(buf,
 948                         rdev->constraints->state_disk.enabled);
 949 }
 950 static DEVICE_ATTR_RO(suspend_disk_state);
 951
 952 static ssize_t suspend_standby_state_show(struct device *dev,
 953                                           struct device_attribute *attr, char *buf)
 954 {
 955         struct regulator_dev *rdev = dev_get_drvdata(dev);
 956
 957         return regulator_print_state(buf,
 958                         rdev->constraints->state_standby.enabled);
 959 }
 960 static DEVICE_ATTR_RO(suspend_standby_state);
 961
 962 static ssize_t bypass_show(struct device *dev,
 963                            struct device_attribute *attr, char *buf)
 964 {
 965         struct regulator_dev *rdev = dev_get_drvdata(dev);
 966         const char *report;
 967         bool bypass;
 968         int ret;
 969
 970         ret = rdev->desc->ops->get_bypass(rdev, &bypass);
 971
 972         if (ret != 0)
 973                 report = "unknown";
 974         else if (bypass)
 975                 report = "enabled";
 976         else
 977                 report = "disabled";
 978
 979         return sprintf(buf, "%s\n", report);
 980 }
 981 static DEVICE_ATTR_RO(bypass);
 982
 983 #define REGULATOR_ERROR_ATTR(name, bit)                                                 \
 984         static ssize_t name##_show(struct device *dev, struct device_attribute *attr,   \
 985                                    char *buf)                                           \
 986         {                                                                               \
 987                 int ret;                                                                \
 988                 unsigned int flags;                                                     \
 989                 struct regulator_dev *rdev = dev_get_drvdata(dev);                      \
 990                 ret = _regulator_get_error_flags(rdev, &flags);                         \
 991                 if (ret)                                                                \
 992                         return ret;                                                     \
 993                 return sysfs_emit(buf, "%d\n", !!(flags & (bit)));                      \
 994         }                                                                               \
 995         static DEVICE_ATTR_RO(name)
 996
 997 REGULATOR_ERROR_ATTR(under_voltage, REGULATOR_ERROR_UNDER_VOLTAGE);
 998 REGULATOR_ERROR_ATTR(over_current, REGULATOR_ERROR_OVER_CURRENT);
 999 REGULATOR_ERROR_ATTR(regulation_out, REGULATOR_ERROR_REGULATION_OUT);
1000 REGULATOR_ERROR_ATTR(fail, REGULATOR_ERROR_FAIL);
1001 REGULATOR_ERROR_ATTR(over_temp, REGULATOR_ERROR_OVER_TEMP);
1002 REGULATOR_ERROR_ATTR(under_voltage_warn, REGULATOR_ERROR_UNDER_VOLTAGE_WARN);
1003 REGULATOR_ERROR_ATTR(over_current_warn, REGULATOR_ERROR_OVER_CURRENT_WARN);
1004 REGULATOR_ERROR_ATTR(over_voltage_warn, REGULATOR_ERROR_OVER_VOLTAGE_WARN);
1005 REGULATOR_ERROR_ATTR(over_temp_warn, REGULATOR_ERROR_OVER_TEMP_WARN);
1006
1007 /* Calculate the new optimum regulator operating mode based on the new total
1008  * consumer load. All locks held by caller
1009  */
1010 static int drms_uA_update(struct regulator_dev *rdev)
1011 {
1012         struct regulator *sibling;
1013         int current_uA = 0, output_uV, input_uV, err;
1014         unsigned int mode;
1015
1016         /*
1017          * first check to see if we can set modes at all, otherwise just
1018          * tell the consumer everything is OK.
1019          */
1020         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_DRMS)) {
1021                 rdev_dbg(rdev, "DRMS operation not allowed\n");
1022                 return 0;
1023         }
1024
1025         if (!rdev->desc->ops->get_optimum_mode &&
1026             !rdev->desc->ops->set_load)
1027                 return 0;
1028
1029         if (!rdev->desc->ops->set_mode &&
1030             !rdev->desc->ops->set_load)
1031                 return -EINVAL;
1032
1033         /* calc total requested load */
1034         list_for_each_entry(sibling, &rdev->consumer_list, list) {
1035                 if (sibling->enable_count)
1036                         current_uA += sibling->uA_load;
1037         }
1038
1039         current_uA += rdev->constraints->system_load;
1040
1041         if (rdev->desc->ops->set_load) {
1042                 /* set the optimum mode for our new total regulator load */
1043                 err = rdev->desc->ops->set_load(rdev, current_uA);
1044                 if (err < 0)
1045                         rdev_err(rdev, "failed to set load %d: %pe\n",
1046                                  current_uA, ERR_PTR(err));
1047         } else {
1048                 /*
1049                  * Unfortunately in some cases the constraints->valid_ops has
1050                  * REGULATOR_CHANGE_DRMS but there are no valid modes listed.
1051                  * That's not really legit but we won't consider it a fatal
1052                  * error here. We'll treat it as if REGULATOR_CHANGE_DRMS
1053                  * wasn't set.
1054                  */
1055                 if (!rdev->constraints->valid_modes_mask) {
1056                         rdev_dbg(rdev, "Can change modes; but no valid mode\n");
1057                         return 0;
1058                 }
1059
1060                 /* get output voltage */
1061                 output_uV = regulator_get_voltage_rdev(rdev);
1062
1063                 /*
1064                  * Don't return an error; if regulator driver cares about
1065                  * output_uV then it's up to the driver to validate.
1066                  */
1067                 if (output_uV <= 0)
1068                         rdev_dbg(rdev, "invalid output voltage found\n");
1069
1070                 /* get input voltage */
1071                 input_uV = 0;
1072                 if (rdev->supply)
1073                         input_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
1074                 if (input_uV <= 0)
1075                         input_uV = rdev->constraints->input_uV;
1076
1077                 /*
1078                  * Don't return an error; if regulator driver cares about
1079                  * input_uV then it's up to the driver to validate.
1080                  */
1081                 if (input_uV <= 0)
1082                         rdev_dbg(rdev, "invalid input voltage found\n");
1083
1084                 /* now get the optimum mode for our new total regulator load */
1085                 mode = rdev->desc->ops->get_optimum_mode(rdev, input_uV,
1086                                                          output_uV, current_uA);
1087
1088                 /* check the new mode is allowed */
1089                 err = regulator_mode_constrain(rdev, &mode);
1090                 if (err < 0) {
1091                         rdev_err(rdev, "failed to get optimum mode @ %d uA %d -> %d uV: %pe\n",
1092                                  current_uA, input_uV, output_uV, ERR_PTR(err));
1093                         return err;
1094                 }
1095
1096                 err = rdev->desc->ops->set_mode(rdev, mode);
1097                 if (err < 0)
1098                         rdev_err(rdev, "failed to set optimum mode %x: %pe\n",
1099                                  mode, ERR_PTR(err));
1100         }
1101
1102         return err;
1103 }
1104
1105 static int __suspend_set_state(struct regulator_dev *rdev,
1106                                const struct regulator_state *rstate)
1107 {
1108         int ret = 0;
1109
1110         if (rstate->enabled == ENABLE_IN_SUSPEND &&
1111                 rdev->desc->ops->set_suspend_enable)
1112                 ret = rdev->desc->ops->set_suspend_enable(rdev);
1113         else if (rstate->enabled == DISABLE_IN_SUSPEND &&
1114                 rdev->desc->ops->set_suspend_disable)
1115                 ret = rdev->desc->ops->set_suspend_disable(rdev);
1116         else /* OK if set_suspend_enable or set_suspend_disable is NULL */
1117                 ret = 0;
1118
1119         if (ret < 0) {
1120                 rdev_err(rdev, "failed to enabled/disable: %pe\n", ERR_PTR(ret));
1121                 return ret;
1122         }
1123
1124         if (rdev->desc->ops->set_suspend_voltage && rstate->uV > 0) {
1125                 ret = rdev->desc->ops->set_suspend_voltage(rdev, rstate->uV);
1126                 if (ret < 0) {
1127                         rdev_err(rdev, "failed to set voltage: %pe\n", ERR_PTR(ret));
1128                         return ret;
1129                 }
1130         }
1131
1132         if (rdev->desc->ops->set_suspend_mode && rstate->mode > 0) {
1133                 ret = rdev->desc->ops->set_suspend_mode(rdev, rstate->mode);
1134                 if (ret < 0) {
1135                         rdev_err(rdev, "failed to set mode: %pe\n", ERR_PTR(ret));
1136                         return ret;
1137                 }
1138         }
1139
1140         return ret;
1141 }
1142
1143 static int suspend_set_initial_state(struct regulator_dev *rdev)
1144 {
1145         const struct regulator_state *rstate;
1146
1147         rstate = regulator_get_suspend_state_check(rdev,
1148                         rdev->constraints->initial_state);
1149         if (!rstate)
1150                 return 0;
1151
1152         return __suspend_set_state(rdev, rstate);
1153 }
1154
1155 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
1156 static void print_constraints_debug(struct regulator_dev *rdev)
1157 {
1158         struct regulation_constraints *constraints = rdev->constraints;
1159         char buf[160] = "";
1160         size_t len = sizeof(buf) - 1;
1161         int count = 0;
1162         int ret;
1163
1164         if (constraints->min_uV && constraints->max_uV) {
1165                 if (constraints->min_uV == constraints->max_uV)
1166                         count += scnprintf(buf + count, len - count, "%d mV ",
1167                                            constraints->min_uV / 1000);
1168                 else
1169                         count += scnprintf(buf + count, len - count,
1170                                            "%d <--> %d mV ",
1171                                            constraints->min_uV / 1000,
1172                                            constraints->max_uV / 1000);
1173         }
1174
1175         if (!constraints->min_uV ||
1176             constraints->min_uV != constraints->max_uV) {
1177                 ret = regulator_get_voltage_rdev(rdev);
1178                 if (ret > 0)
1179                         count += scnprintf(buf + count, len - count,
1180                                            "at %d mV ", ret / 1000);
1181         }
1182
1183         if (constraints->uV_offset)
1184                 count += scnprintf(buf + count, len - count, "%dmV offset ",
1185                                    constraints->uV_offset / 1000);
1186
1187         if (constraints->min_uA && constraints->max_uA) {
1188                 if (constraints->min_uA == constraints->max_uA)
1189                         count += scnprintf(buf + count, len - count, "%d mA ",
1190                                            constraints->min_uA / 1000);
1191                 else
1192                         count += scnprintf(buf + count, len - count,
1193                                            "%d <--> %d mA ",
1194                                            constraints->min_uA / 1000,
1195                                            constraints->max_uA / 1000);
1196         }
1197
1198         if (!constraints->min_uA ||
1199             constraints->min_uA != constraints->max_uA) {
1200                 ret = _regulator_get_current_limit(rdev);
1201                 if (ret > 0)
1202                         count += scnprintf(buf + count, len - count,
1203                                            "at %d mA ", ret / 1000);
1204         }
1205
1206         if (constraints->valid_modes_mask & REGULATOR_MODE_FAST)
1207                 count += scnprintf(buf + count, len - count, "fast ");
1208         if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL)
1209                 count += scnprintf(buf + count, len - count, "normal ");
1210         if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE)
1211                 count += scnprintf(buf + count, len - count, "idle ");
1212         if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
1213                 count += scnprintf(buf + count, len - count, "standby ");
1214
1215         if (!count)
1216                 count = scnprintf(buf, len, "no parameters");
1217         else
1218                 --count;
1219
1220         count += scnprintf(buf + count, len - count, ", %s",
1221                 _regulator_is_enabled(rdev) ? "enabled" : "disabled");
1222
1223         rdev_dbg(rdev, "%s\n", buf);
1224 }
1225 #else /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1226 static inline void print_constraints_debug(struct regulator_dev *rdev) {}
1227 #endif /* !DEBUG && !CONFIG_DYNAMIC_DEBUG */
1228
1229 static void print_constraints(struct regulator_dev *rdev)
1230 {
1231         struct regulation_constraints *constraints = rdev->constraints;
1232
1233         print_constraints_debug(rdev);
1234
1235         if ((constraints->min_uV != constraints->max_uV) &&
1236             !regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
1237                 rdev_warn(rdev,
1238                           "Voltage range but no REGULATOR_CHANGE_VOLTAGE\n");
1239 }
1240
1241 static int machine_constraints_voltage(struct regulator_dev *rdev,
1242         struct regulation_constraints *constraints)
1243 {
1244         const struct regulator_ops *ops = rdev->desc->ops;
1245         int ret;
1246
1247         /* do we need to apply the constraint voltage */
1248         if (rdev->constraints->apply_uV &&
1249             rdev->constraints->min_uV && rdev->constraints->max_uV) {
1250                 int target_min, target_max;
1251                 int current_uV = regulator_get_voltage_rdev(rdev);
1252
1253                 if (current_uV == -ENOTRECOVERABLE) {
1254                         /* This regulator can't be read and must be initialized */
1255                         rdev_info(rdev, "Setting %d-%duV\n",
1256                                   rdev->constraints->min_uV,
1257                                   rdev->constraints->max_uV);
1258                         _regulator_do_set_voltage(rdev,
1259                                                   rdev->constraints->min_uV,
1260                                                   rdev->constraints->max_uV);
1261                         current_uV = regulator_get_voltage_rdev(rdev);
1262                 }
1263
1264                 if (current_uV < 0) {
1265                         if (current_uV != -EPROBE_DEFER)
1266                                 rdev_err(rdev,
1267                                          "failed to get the current voltage: %pe\n",
1268                                          ERR_PTR(current_uV));
1269                         return current_uV;
1270                 }
1271
1272                 /*
1273                  * If we're below the minimum voltage move up to the
1274                  * minimum voltage, if we're above the maximum voltage
1275                  * then move down to the maximum.
1276                  */
1277                 target_min = current_uV;
1278                 target_max = current_uV;
1279
1280                 if (current_uV < rdev->constraints->min_uV) {
1281                         target_min = rdev->constraints->min_uV;
1282                         target_max = rdev->constraints->min_uV;
1283                 }
1284
1285                 if (current_uV > rdev->constraints->max_uV) {
1286                         target_min = rdev->constraints->max_uV;
1287                         target_max = rdev->constraints->max_uV;
1288                 }
1289
1290                 if (target_min != current_uV || target_max != current_uV) {
1291                         rdev_info(rdev, "Bringing %duV into %d-%duV\n",
1292                                   current_uV, target_min, target_max);
1293                         ret = _regulator_do_set_voltage(
1294                                 rdev, target_min, target_max);
1295                         if (ret < 0) {
1296                                 rdev_err(rdev,
1297                                         "failed to apply %d-%duV constraint: %pe\n",
1298                                         target_min, target_max, ERR_PTR(ret));
1299                                 return ret;
1300                         }
1301                 }
1302         }
1303
1304         /* constrain machine-level voltage specs to fit
1305          * the actual range supported by this regulator.
1306          */
1307         if (ops->list_voltage && rdev->desc->n_voltages) {
1308                 int     count = rdev->desc->n_voltages;
1309                 int     i;
1310                 int     min_uV = INT_MAX;
1311                 int     max_uV = INT_MIN;
1312                 int     cmin = constraints->min_uV;
1313                 int     cmax = constraints->max_uV;
1314
1315                 /* it's safe to autoconfigure fixed-voltage supplies
1316                  * and the constraints are used by list_voltage.
1317                  */
1318                 if (count == 1 && !cmin) {
1319                         cmin = 1;
1320                         cmax = INT_MAX;
1321                         constraints->min_uV = cmin;
1322                         constraints->max_uV = cmax;
1323                 }
1324
1325                 /* voltage constraints are optional */
1326                 if ((cmin == 0) && (cmax == 0))
1327                         return 0;
1328
1329                 /* else require explicit machine-level constraints */
1330                 if (cmin <= 0 || cmax <= 0 || cmax < cmin) {
1331                         rdev_err(rdev, "invalid voltage constraints\n");
1332                         return -EINVAL;
1333                 }
1334
1335                 /* no need to loop voltages if range is continuous */
1336                 if (rdev->desc->continuous_voltage_range)
1337                         return 0;
1338
1339                 /* initial: [cmin..cmax] valid, [min_uV..max_uV] not */
1340                 for (i = 0; i < count; i++) {
1341                         int     value;
1342
1343                         value = ops->list_voltage(rdev, i);
1344                         if (value <= 0)
1345                                 continue;
1346
1347                         /* maybe adjust [min_uV..max_uV] */
1348                         if (value >= cmin && value < min_uV)
1349                                 min_uV = value;
1350                         if (value <= cmax && value > max_uV)
1351                                 max_uV = value;
1352                 }
1353
1354                 /* final: [min_uV..max_uV] valid iff constraints valid */
1355                 if (max_uV < min_uV) {
1356                         rdev_err(rdev,
1357                                  "unsupportable voltage constraints %u-%uuV\n",
1358                                  min_uV, max_uV);
1359                         return -EINVAL;
1360                 }
1361
1362                 /* use regulator's subset of machine constraints */
1363                 if (constraints->min_uV < min_uV) {
1364                         rdev_dbg(rdev, "override min_uV, %d -> %d\n",
1365                                  constraints->min_uV, min_uV);
1366                         constraints->min_uV = min_uV;
1367                 }
1368                 if (constraints->max_uV > max_uV) {
1369                         rdev_dbg(rdev, "override max_uV, %d -> %d\n",
1370                                  constraints->max_uV, max_uV);
1371                         constraints->max_uV = max_uV;
1372                 }
1373         }
1374
1375         return 0;
1376 }
1377
1378 static int machine_constraints_current(struct regulator_dev *rdev,
1379         struct regulation_constraints *constraints)
1380 {
1381         const struct regulator_ops *ops = rdev->desc->ops;
1382         int ret;
1383
1384         if (!constraints->min_uA && !constraints->max_uA)
1385                 return 0;
1386
1387         if (constraints->min_uA > constraints->max_uA) {
1388                 rdev_err(rdev, "Invalid current constraints\n");
1389                 return -EINVAL;
1390         }
1391
1392         if (!ops->set_current_limit || !ops->get_current_limit) {
1393                 rdev_warn(rdev, "Operation of current configuration missing\n");
1394                 return 0;
1395         }
1396
1397         /* Set regulator current in constraints range */
1398         ret = ops->set_current_limit(rdev, constraints->min_uA,
1399                         constraints->max_uA);
1400         if (ret < 0) {
1401                 rdev_err(rdev, "Failed to set current constraint, %d\n", ret);
1402                 return ret;
1403         }
1404
1405         return 0;
1406 }
1407
1408 static int _regulator_do_enable(struct regulator_dev *rdev);
1409
1410 static int notif_set_limit(struct regulator_dev *rdev,
1411                            int (*set)(struct regulator_dev *, int, int, bool),
1412                            int limit, int severity)
1413 {
1414         bool enable;
1415
1416         if (limit == REGULATOR_NOTIF_LIMIT_DISABLE) {
1417                 enable = false;
1418                 limit = 0;
1419         } else {
1420                 enable = true;
1421         }
1422
1423         if (limit == REGULATOR_NOTIF_LIMIT_ENABLE)
1424                 limit = 0;
1425
1426         return set(rdev, limit, severity, enable);
1427 }
1428
1429 static int handle_notify_limits(struct regulator_dev *rdev,
1430                         int (*set)(struct regulator_dev *, int, int, bool),
1431                         struct notification_limit *limits)
1432 {
1433         int ret = 0;
1434
1435         if (!set)
1436                 return -EOPNOTSUPP;
1437
1438         if (limits->prot)
1439                 ret = notif_set_limit(rdev, set, limits->prot,
1440                                       REGULATOR_SEVERITY_PROT);
1441         if (ret)
1442                 return ret;
1443
1444         if (limits->err)
1445                 ret = notif_set_limit(rdev, set, limits->err,
1446                                       REGULATOR_SEVERITY_ERR);
1447         if (ret)
1448                 return ret;
1449
1450         if (limits->warn)
1451                 ret = notif_set_limit(rdev, set, limits->warn,
1452                                       REGULATOR_SEVERITY_WARN);
1453
1454         return ret;
1455 }
1456 /**
1457  * set_machine_constraints - sets regulator constraints
1458  * @rdev: regulator source
1459  *
1460  * Allows platform initialisation code to define and constrain
1461  * regulator circuits e.g. valid voltage/current ranges, etc.  NOTE:
1462  * Constraints *must* be set by platform code in order for some
1463  * regulator operations to proceed i.e. set_voltage, set_current_limit,
1464  * set_mode.
1465  */
1466 static int set_machine_constraints(struct regulator_dev *rdev)
1467 {
1468         int ret = 0;
1469         const struct regulator_ops *ops = rdev->desc->ops;
1470
1471         ret = machine_constraints_voltage(rdev, rdev->constraints);
1472         if (ret != 0)
1473                 return ret;
1474
1475         ret = machine_constraints_current(rdev, rdev->constraints);
1476         if (ret != 0)
1477                 return ret;
1478
1479         if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
1480                 ret = ops->set_input_current_limit(rdev,
1481                                                    rdev->constraints->ilim_uA);
1482                 if (ret < 0) {
1483                         rdev_err(rdev, "failed to set input limit: %pe\n", ERR_PTR(ret));
1484                         return ret;
1485                 }
1486         }
1487
1488         /* do we need to setup our suspend state */
1489         if (rdev->constraints->initial_state) {
1490                 ret = suspend_set_initial_state(rdev);
1491                 if (ret < 0) {
1492                         rdev_err(rdev, "failed to set suspend state: %pe\n", ERR_PTR(ret));
1493                         return ret;
1494                 }
1495         }
1496
1497         if (rdev->constraints->initial_mode) {
1498                 if (!ops->set_mode) {
1499                         rdev_err(rdev, "no set_mode operation\n");
1500                         return -EINVAL;
1501                 }
1502
1503                 ret = ops->set_mode(rdev, rdev->constraints->initial_mode);
1504                 if (ret < 0) {
1505                         rdev_err(rdev, "failed to set initial mode: %pe\n", ERR_PTR(ret));
1506                         return ret;
1507                 }
1508         } else if (rdev->constraints->system_load) {
1509                 /*
1510                  * We'll only apply the initial system load if an
1511                  * initial mode wasn't specified.
1512                  */
1513                 drms_uA_update(rdev);
1514         }
1515
1516         if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable)
1517                 && ops->set_ramp_delay) {
1518                 ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay);
1519                 if (ret < 0) {
1520                         rdev_err(rdev, "failed to set ramp_delay: %pe\n", ERR_PTR(ret));
1521                         return ret;
1522                 }
1523         }
1524
1525         if (rdev->constraints->pull_down && ops->set_pull_down) {
1526                 ret = ops->set_pull_down(rdev);
1527                 if (ret < 0) {
1528                         rdev_err(rdev, "failed to set pull down: %pe\n", ERR_PTR(ret));
1529                         return ret;
1530                 }
1531         }
1532
1533         if (rdev->constraints->soft_start && ops->set_soft_start) {
1534                 ret = ops->set_soft_start(rdev);
1535                 if (ret < 0) {
1536                         rdev_err(rdev, "failed to set soft start: %pe\n", ERR_PTR(ret));
1537                         return ret;
1538                 }
1539         }
1540
1541         /*
1542          * Existing logic does not warn if over_current_protection is given as
1543          * a constraint but driver does not support that. I think we should
1544          * warn about this type of issues as it is possible someone changes
1545          * PMIC on board to another type - and the another PMIC's driver does
1546          * not support setting protection. Board composer may happily believe
1547          * the DT limits are respected - especially if the new PMIC HW also
1548          * supports protection but the driver does not. I won't change the logic
1549          * without hearing more experienced opinion on this though.
1550          *
1551          * If warning is seen as a good idea then we can merge handling the
1552          * over-curret protection and detection and get rid of this special
1553          * handling.
1554          */
1555         if (rdev->constraints->over_current_protection
1556                 && ops->set_over_current_protection) {
1557                 int lim = rdev->constraints->over_curr_limits.prot;
1558
1559                 ret = ops->set_over_current_protection(rdev, lim,
1560                                                        REGULATOR_SEVERITY_PROT,
1561                                                        true);
1562                 if (ret < 0) {
1563                         rdev_err(rdev, "failed to set over current protection: %pe\n",
1564                                  ERR_PTR(ret));
1565                         return ret;
1566                 }
1567         }
1568
1569         if (rdev->constraints->over_current_detection)
1570                 ret = handle_notify_limits(rdev,
1571                                            ops->set_over_current_protection,
1572                                            &rdev->constraints->over_curr_limits);
1573         if (ret) {
1574                 if (ret != -EOPNOTSUPP) {
1575                         rdev_err(rdev, "failed to set over current limits: %pe\n",
1576                                  ERR_PTR(ret));
1577                         return ret;
1578                 }
1579                 rdev_warn(rdev,
1580                           "IC does not support requested over-current limits\n");
1581         }
1582
1583         if (rdev->constraints->over_voltage_detection)
1584                 ret = handle_notify_limits(rdev,
1585                                            ops->set_over_voltage_protection,
1586                                            &rdev->constraints->over_voltage_limits);
1587         if (ret) {
1588                 if (ret != -EOPNOTSUPP) {
1589                         rdev_err(rdev, "failed to set over voltage limits %pe\n",
1590                                  ERR_PTR(ret));
1591                         return ret;
1592                 }
1593                 rdev_warn(rdev,
1594                           "IC does not support requested over voltage limits\n");
1595         }
1596
1597         if (rdev->constraints->under_voltage_detection)
1598                 ret = handle_notify_limits(rdev,
1599                                            ops->set_under_voltage_protection,
1600                                            &rdev->constraints->under_voltage_limits);
1601         if (ret) {
1602                 if (ret != -EOPNOTSUPP) {
1603                         rdev_err(rdev, "failed to set under voltage limits %pe\n",
1604                                  ERR_PTR(ret));
1605                         return ret;
1606                 }
1607                 rdev_warn(rdev,
1608                           "IC does not support requested under voltage limits\n");
1609         }
1610
1611         if (rdev->constraints->over_temp_detection)
1612                 ret = handle_notify_limits(rdev,
1613                                            ops->set_thermal_protection,
1614                                            &rdev->constraints->temp_limits);
1615         if (ret) {
1616                 if (ret != -EOPNOTSUPP) {
1617                         rdev_err(rdev, "failed to set temperature limits %pe\n",
1618                                  ERR_PTR(ret));
1619                         return ret;
1620                 }
1621                 rdev_warn(rdev,
1622                           "IC does not support requested temperature limits\n");
1623         }
1624
1625         if (rdev->constraints->active_discharge && ops->set_active_discharge) {
1626                 bool ad_state = (rdev->constraints->active_discharge ==
1627                               REGULATOR_ACTIVE_DISCHARGE_ENABLE) ? true : false;
1628
1629                 ret = ops->set_active_discharge(rdev, ad_state);
1630                 if (ret < 0) {
1631                         rdev_err(rdev, "failed to set active discharge: %pe\n", ERR_PTR(ret));
1632                         return ret;
1633                 }
1634         }
1635
1636         /*
1637          * If there is no mechanism for controlling the regulator then
1638          * flag it as always_on so we don't end up duplicating checks
1639          * for this so much.  Note that we could control the state of
1640          * a supply to control the output on a regulator that has no
1641          * direct control.
1642          */
1643         if (!rdev->ena_pin && !ops->enable) {
1644                 if (rdev->supply_name && !rdev->supply)
1645                         return -EPROBE_DEFER;
1646
1647                 if (rdev->supply)
1648                         rdev->constraints->always_on =
1649                                 rdev->supply->rdev->constraints->always_on;
1650                 else
1651                         rdev->constraints->always_on = true;
1652         }
1653
1654         /* If the constraints say the regulator should be on at this point
1655          * and we have control then make sure it is enabled.
1656          */
1657         if (rdev->constraints->always_on || rdev->constraints->boot_on) {
1658                 /* If we want to enable this regulator, make sure that we know
1659                  * the supplying regulator.
1660                  */
1661                 if (rdev->supply_name && !rdev->supply)
1662                         return -EPROBE_DEFER;
1663
1664                 /* If supplying regulator has already been enabled,
1665                  * it's not intended to have use_count increment
1666                  * when rdev is only boot-on.
1667                  */
1668                 if (rdev->supply &&
1669                     (rdev->constraints->always_on ||
1670                      !regulator_is_enabled(rdev->supply))) {
1671                         ret = regulator_enable(rdev->supply);
1672                         if (ret < 0) {
1673                                 _regulator_put(rdev->supply);
1674                                 rdev->supply = NULL;
1675                                 return ret;
1676                         }
1677                 }
1678
1679                 ret = _regulator_do_enable(rdev);
1680                 if (ret < 0 && ret != -EINVAL) {
1681                         rdev_err(rdev, "failed to enable: %pe\n", ERR_PTR(ret));
1682                         return ret;
1683                 }
1684
1685                 if (rdev->constraints->always_on)
1686                         rdev->use_count++;
1687         } else if (rdev->desc->off_on_delay) {
1688                 rdev->last_off = ktime_get();
1689         }
1690
1691         print_constraints(rdev);
1692         return 0;
1693 }
1694
1695 /**
1696  * set_supply - set regulator supply regulator
1697  * @rdev: regulator (locked)
1698  * @supply_rdev: supply regulator (locked))
1699  *
1700  * Called by platform initialisation code to set the supply regulator for this
1701  * regulator. This ensures that a regulators supply will also be enabled by the
1702  * core if it's child is enabled.
1703  */
1704 static int set_supply(struct regulator_dev *rdev,
1705                       struct regulator_dev *supply_rdev)
1706 {
1707         int err;
1708
1709         rdev_dbg(rdev, "supplied by %s\n", rdev_get_name(supply_rdev));
1710
1711         if (!try_module_get(supply_rdev->owner))
1712                 return -ENODEV;
1713
1714         rdev->supply = create_regulator(supply_rdev, &rdev->dev, "SUPPLY");
1715         if (rdev->supply == NULL) {
1716                 module_put(supply_rdev->owner);
1717                 err = -ENOMEM;
1718                 return err;
1719         }
1720         supply_rdev->open_count++;
1721
1722         return 0;
1723 }
1724
1725 /**
1726  * set_consumer_device_supply - Bind a regulator to a symbolic supply
1727  * @rdev:         regulator source
1728  * @consumer_dev_name: dev_name() string for device supply applies to
1729  * @supply:       symbolic name for supply
1730  *
1731  * Allows platform initialisation code to map physical regulator
1732  * sources to symbolic names for supplies for use by devices.  Devices
1733  * should use these symbolic names to request regulators, avoiding the
1734  * need to provide board-specific regulator names as platform data.
1735  */
1736 static int set_consumer_device_supply(struct regulator_dev *rdev,
1737                                       const char *consumer_dev_name,
1738                                       const char *supply)
1739 {
1740         struct regulator_map *node, *new_node;
1741         int has_dev;
1742
1743         if (supply == NULL)
1744                 return -EINVAL;
1745
1746         if (consumer_dev_name != NULL)
1747                 has_dev = 1;
1748         else
1749                 has_dev = 0;
1750
1751         new_node = kzalloc(sizeof(struct regulator_map), GFP_KERNEL);
1752         if (new_node == NULL)
1753                 return -ENOMEM;
1754
1755         new_node->regulator = rdev;
1756         new_node->supply = supply;
1757
1758         if (has_dev) {
1759                 new_node->dev_name = kstrdup(consumer_dev_name, GFP_KERNEL);
1760                 if (new_node->dev_name == NULL) {
1761                         kfree(new_node);
1762                         return -ENOMEM;
1763                 }
1764         }
1765
1766         mutex_lock(&regulator_list_mutex);
1767         list_for_each_entry(node, &regulator_map_list, list) {
1768                 if (node->dev_name && consumer_dev_name) {
1769                         if (strcmp(node->dev_name, consumer_dev_name) != 0)
1770                                 continue;
1771                 } else if (node->dev_name || consumer_dev_name) {
1772                         continue;
1773                 }
1774
1775                 if (strcmp(node->supply, supply) != 0)
1776                         continue;
1777
1778                 pr_debug("%s: %s/%s is '%s' supply; fail %s/%s\n",
1779                          consumer_dev_name,
1780                          dev_name(&node->regulator->dev),
1781                          node->regulator->desc->name,
1782                          supply,
1783                          dev_name(&rdev->dev), rdev_get_name(rdev));
1784                 goto fail;
1785         }
1786
1787         list_add(&new_node->list, &regulator_map_list);
1788         mutex_unlock(&regulator_list_mutex);
1789
1790         return 0;
1791
1792 fail:
1793         mutex_unlock(&regulator_list_mutex);
1794         kfree(new_node->dev_name);
1795         kfree(new_node);
1796         return -EBUSY;
1797 }
1798
1799 static void unset_regulator_supplies(struct regulator_dev *rdev)
1800 {
1801         struct regulator_map *node, *n;
1802
1803         list_for_each_entry_safe(node, n, &regulator_map_list, list) {
1804                 if (rdev == node->regulator) {
1805                         list_del(&node->list);
1806                         kfree(node->dev_name);
1807                         kfree(node);
1808                 }
1809         }
1810 }
1811
1812 #ifdef CONFIG_DEBUG_FS
1813 static ssize_t constraint_flags_read_file(struct file *file,
1814                                           char __user *user_buf,
1815                                           size_t count, loff_t *ppos)
1816 {
1817         const struct regulator *regulator = file->private_data;
1818         const struct regulation_constraints *c = regulator->rdev->constraints;
1819         char *buf;
1820         ssize_t ret;
1821
1822         if (!c)
1823                 return 0;
1824
1825         buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1826         if (!buf)
1827                 return -ENOMEM;
1828
1829         ret = snprintf(buf, PAGE_SIZE,
1830                         "always_on: %u\n"
1831                         "boot_on: %u\n"
1832                         "apply_uV: %u\n"
1833                         "ramp_disable: %u\n"
1834                         "soft_start: %u\n"
1835                         "pull_down: %u\n"
1836                         "over_current_protection: %u\n",
1837                         c->always_on,
1838                         c->boot_on,
1839                         c->apply_uV,
1840                         c->ramp_disable,
1841                         c->soft_start,
1842                         c->pull_down,
1843                         c->over_current_protection);
1844
1845         ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
1846         kfree(buf);
1847
1848         return ret;
1849 }
1850
1851 #endif
1852
1853 static const struct file_operations constraint_flags_fops = {
1854 #ifdef CONFIG_DEBUG_FS
1855         .open = simple_open,
1856         .read = constraint_flags_read_file,
1857         .llseek = default_llseek,
1858 #endif
1859 };
1860
1861 #define REG_STR_SIZE    64
1862
1863 static struct regulator *create_regulator(struct regulator_dev *rdev,
1864                                           struct device *dev,
1865                                           const char *supply_name)
1866 {
1867         struct regulator *regulator;
1868         int err = 0;
1869
1870         lockdep_assert_held_once(&rdev->mutex.base);
1871
1872         if (dev) {
1873                 char buf[REG_STR_SIZE];
1874                 int size;
1875
1876                 size = snprintf(buf, REG_STR_SIZE, "%s-%s",
1877                                 dev->kobj.name, supply_name);
1878                 if (size >= REG_STR_SIZE)
1879                         return NULL;
1880
1881                 supply_name = kstrdup(buf, GFP_KERNEL);
1882                 if (supply_name == NULL)
1883                         return NULL;
1884         } else {
1885                 supply_name = kstrdup_const(supply_name, GFP_KERNEL);
1886                 if (supply_name == NULL)
1887                         return NULL;
1888         }
1889
1890         regulator = kzalloc(sizeof(*regulator), GFP_KERNEL);
1891         if (regulator == NULL) {
1892                 kfree_const(supply_name);
1893                 return NULL;
1894         }
1895
1896         regulator->rdev = rdev;
1897         regulator->supply_name = supply_name;
1898
1899         list_add(&regulator->list, &rdev->consumer_list);
1900
1901         if (dev) {
1902                 regulator->dev = dev;
1903
1904                 /* Add a link to the device sysfs entry */
1905                 err = sysfs_create_link_nowarn(&rdev->dev.kobj, &dev->kobj,
1906                                                supply_name);
1907                 if (err) {
1908                         rdev_dbg(rdev, "could not add device link %s: %pe\n",
1909                                   dev->kobj.name, ERR_PTR(err));
1910                         /* non-fatal */
1911                 }
1912         }
1913
1914         if (err != -EEXIST)
1915                 regulator->debugfs = debugfs_create_dir(supply_name, rdev->debugfs);
1916         if (IS_ERR(regulator->debugfs))
1917                 rdev_dbg(rdev, "Failed to create debugfs directory\n");
1918
1919         debugfs_create_u32("uA_load", 0444, regulator->debugfs,
1920                            &regulator->uA_load);
1921         debugfs_create_u32("min_uV", 0444, regulator->debugfs,
1922                            &regulator->voltage[PM_SUSPEND_ON].min_uV);
1923         debugfs_create_u32("max_uV", 0444, regulator->debugfs,
1924                            &regulator->voltage[PM_SUSPEND_ON].max_uV);
1925         debugfs_create_file("constraint_flags", 0444, regulator->debugfs,
1926                             regulator, &constraint_flags_fops);
1927
1928         /*
1929          * Check now if the regulator is an always on regulator - if
1930          * it is then we don't need to do nearly so much work for
1931          * enable/disable calls.
1932          */
1933         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS) &&
1934             _regulator_is_enabled(rdev))
1935                 regulator->always_on = true;
1936
1937         return regulator;
1938 }
1939
1940 static int _regulator_get_enable_time(struct regulator_dev *rdev)
1941 {
1942         if (rdev->constraints && rdev->constraints->enable_time)
1943                 return rdev->constraints->enable_time;
1944         if (rdev->desc->ops->enable_time)
1945                 return rdev->desc->ops->enable_time(rdev);
1946         return rdev->desc->enable_time;
1947 }
1948
1949 static struct regulator_supply_alias *regulator_find_supply_alias(
1950                 struct device *dev, const char *supply)
1951 {
1952         struct regulator_supply_alias *map;
1953
1954         list_for_each_entry(map, &regulator_supply_alias_list, list)
1955                 if (map->src_dev == dev && strcmp(map->src_supply, supply) == 0)
1956                         return map;
1957
1958         return NULL;
1959 }
1960
1961 static void regulator_supply_alias(struct device **dev, const char **supply)
1962 {
1963         struct regulator_supply_alias *map;
1964
1965         map = regulator_find_supply_alias(*dev, *supply);
1966         if (map) {
1967                 dev_dbg(*dev, "Mapping supply %s to %s,%s\n",
1968                                 *supply, map->alias_supply,
1969                                 dev_name(map->alias_dev));
1970                 *dev = map->alias_dev;
1971                 *supply = map->alias_supply;
1972         }
1973 }
1974
1975 static int regulator_match(struct device *dev, const void *data)
1976 {
1977         struct regulator_dev *r = dev_to_rdev(dev);
1978
1979         return strcmp(rdev_get_name(r), data) == 0;
1980 }
1981
1982 static struct regulator_dev *regulator_lookup_by_name(const char *name)
1983 {
1984         struct device *dev;
1985
1986         dev = class_find_device(&regulator_class, NULL, name, regulator_match);
1987
1988         return dev ? dev_to_rdev(dev) : NULL;
1989 }
1990
1991 /**
1992  * regulator_dev_lookup - lookup a regulator device.
1993  * @dev: device for regulator "consumer".
1994  * @supply: Supply name or regulator ID.
1995  *
1996  * If successful, returns a struct regulator_dev that corresponds to the name
1997  * @supply and with the embedded struct device refcount incremented by one.
1998  * The refcount must be dropped by calling put_device().
1999  * On failure one of the following ERR-PTR-encoded values is returned:
2000  * -ENODEV if lookup fails permanently, -EPROBE_DEFER if lookup could succeed
2001  * in the future.
2002  */
2003 static struct regulator_dev *regulator_dev_lookup(struct device *dev,
2004                                                   const char *supply)
2005 {
2006         struct regulator_dev *r = NULL;
2007         struct device_node *node;
2008         struct regulator_map *map;
2009         const char *devname = NULL;
2010
2011         regulator_supply_alias(&dev, &supply);
2012
2013         /* first do a dt based lookup */
2014         if (dev && dev->of_node) {
2015                 node = of_get_regulator(dev, supply);
2016                 if (node) {
2017                         r = of_find_regulator_by_node(node);
2018                         of_node_put(node);
2019                         if (r)
2020                                 return r;
2021
2022                         /*
2023                          * We have a node, but there is no device.
2024                          * assume it has not registered yet.
2025                          */
2026                         return ERR_PTR(-EPROBE_DEFER);
2027                 }
2028         }
2029
2030         /* if not found, try doing it non-dt way */
2031         if (dev)
2032                 devname = dev_name(dev);
2033
2034         mutex_lock(&regulator_list_mutex);
2035         list_for_each_entry(map, &regulator_map_list, list) {
2036                 /* If the mapping has a device set up it must match */
2037                 if (map->dev_name &&
2038                     (!devname || strcmp(map->dev_name, devname)))
2039                         continue;
2040
2041                 if (strcmp(map->supply, supply) == 0 &&
2042                     get_device(&map->regulator->dev)) {
2043                         r = map->regulator;
2044                         break;
2045                 }
2046         }
2047         mutex_unlock(&regulator_list_mutex);
2048
2049         if (r)
2050                 return r;
2051
2052         r = regulator_lookup_by_name(supply);
2053         if (r)
2054                 return r;
2055
2056         return ERR_PTR(-ENODEV);
2057 }
2058
2059 static int regulator_resolve_supply(struct regulator_dev *rdev)
2060 {
2061         struct regulator_dev *r;
2062         struct device *dev = rdev->dev.parent;
2063         struct ww_acquire_ctx ww_ctx;
2064         int ret = 0;
2065
2066         /* No supply to resolve? */
2067         if (!rdev->supply_name)
2068                 return 0;
2069
2070         /* Supply already resolved? (fast-path without locking contention) */
2071         if (rdev->supply)
2072                 return 0;
2073
2074         r = regulator_dev_lookup(dev, rdev->supply_name);
2075         if (IS_ERR(r)) {
2076                 ret = PTR_ERR(r);
2077
2078                 /* Did the lookup explicitly defer for us? */
2079                 if (ret == -EPROBE_DEFER)
2080                         goto out;
2081
2082                 if (have_full_constraints()) {
2083                         r = dummy_regulator_rdev;
2084                         get_device(&r->dev);
2085                 } else {
2086                         dev_err(dev, "Failed to resolve %s-supply for %s\n",
2087                                 rdev->supply_name, rdev->desc->name);
2088                         ret = -EPROBE_DEFER;
2089                         goto out;
2090                 }
2091         }
2092
2093         if (r == rdev) {
2094                 dev_err(dev, "Supply for %s (%s) resolved to itself\n",
2095                         rdev->desc->name, rdev->supply_name);
2096                 if (!have_full_constraints()) {
2097                         ret = -EINVAL;
2098                         goto out;
2099                 }
2100                 r = dummy_regulator_rdev;
2101                 get_device(&r->dev);
2102         }
2103
2104         /*
2105          * If the supply's parent device is not the same as the
2106          * regulator's parent device, then ensure the parent device
2107          * is bound before we resolve the supply, in case the parent
2108          * device get probe deferred and unregisters the supply.
2109          */
2110         if (r->dev.parent && r->dev.parent != rdev->dev.parent) {
2111                 if (!device_is_bound(r->dev.parent)) {
2112                         put_device(&r->dev);
2113                         ret = -EPROBE_DEFER;
2114                         goto out;
2115                 }
2116         }
2117
2118         /* Recursively resolve the supply of the supply */
2119         ret = regulator_resolve_supply(r);
2120         if (ret < 0) {
2121                 put_device(&r->dev);
2122                 goto out;
2123         }
2124
2125         /*
2126          * Recheck rdev->supply with rdev->mutex lock held to avoid a race
2127          * between rdev->supply null check and setting rdev->supply in
2128          * set_supply() from concurrent tasks.
2129          */
2130         regulator_lock_two(rdev, r, &ww_ctx);
2131
2132         /* Supply just resolved by a concurrent task? */
2133         if (rdev->supply) {
2134                 regulator_unlock_two(rdev, r, &ww_ctx);
2135                 put_device(&r->dev);
2136                 goto out;
2137         }
2138
2139         ret = set_supply(rdev, r);
2140         if (ret < 0) {
2141                 regulator_unlock_two(rdev, r, &ww_ctx);
2142                 put_device(&r->dev);
2143                 goto out;
2144         }
2145
2146         regulator_unlock_two(rdev, r, &ww_ctx);
2147
2148         /*
2149          * In set_machine_constraints() we may have turned this regulator on
2150          * but we couldn't propagate to the supply if it hadn't been resolved
2151          * yet.  Do it now.
2152          */
2153         if (rdev->use_count) {
2154                 ret = regulator_enable(rdev->supply);
2155                 if (ret < 0) {
2156                         _regulator_put(rdev->supply);
2157                         rdev->supply = NULL;
2158                         goto out;
2159                 }
2160         }
2161
2162 out:
2163         return ret;
2164 }
2165
2166 /* Internal regulator request function */
2167 struct regulator *_regulator_get(struct device *dev, const char *id,
2168                                  enum regulator_get_type get_type)
2169 {
2170         struct regulator_dev *rdev;
2171         struct regulator *regulator;
2172         struct device_link *link;
2173         int ret;
2174
2175         if (get_type >= MAX_GET_TYPE) {
2176                 dev_err(dev, "invalid type %d in %s\n", get_type, __func__);
2177                 return ERR_PTR(-EINVAL);
2178         }
2179
2180         if (id == NULL) {
2181                 pr_err("get() with no identifier\n");
2182                 return ERR_PTR(-EINVAL);
2183         }
2184
2185         rdev = regulator_dev_lookup(dev, id);
2186         if (IS_ERR(rdev)) {
2187                 ret = PTR_ERR(rdev);
2188
2189                 /*
2190                  * If regulator_dev_lookup() fails with error other
2191                  * than -ENODEV our job here is done, we simply return it.
2192                  */
2193                 if (ret != -ENODEV)
2194                         return ERR_PTR(ret);
2195
2196                 if (!have_full_constraints()) {
2197                         dev_warn(dev,
2198                                  "incomplete constraints, dummy supplies not allowed\n");
2199                         return ERR_PTR(-ENODEV);
2200                 }
2201
2202                 switch (get_type) {
2203                 case NORMAL_GET:
2204                         /*
2205                          * Assume that a regulator is physically present and
2206                          * enabled, even if it isn't hooked up, and just
2207                          * provide a dummy.
2208                          */
2209                         dev_warn(dev, "supply %s not found, using dummy regulator\n", id);
2210                         rdev = dummy_regulator_rdev;
2211                         get_device(&rdev->dev);
2212                         break;
2213
2214                 case EXCLUSIVE_GET:
2215                         dev_warn(dev,
2216                                  "dummy supplies not allowed for exclusive requests\n");
2217                         fallthrough;
2218
2219                 default:
2220                         return ERR_PTR(-ENODEV);
2221                 }
2222         }
2223
2224         if (rdev->exclusive) {
2225                 regulator = ERR_PTR(-EPERM);
2226                 put_device(&rdev->dev);
2227                 return regulator;
2228         }
2229
2230         if (get_type == EXCLUSIVE_GET && rdev->open_count) {
2231                 regulator = ERR_PTR(-EBUSY);
2232                 put_device(&rdev->dev);
2233                 return regulator;
2234         }
2235
2236         mutex_lock(&regulator_list_mutex);
2237         ret = (rdev->coupling_desc.n_resolved != rdev->coupling_desc.n_coupled);
2238         mutex_unlock(&regulator_list_mutex);
2239
2240         if (ret != 0) {
2241                 regulator = ERR_PTR(-EPROBE_DEFER);
2242                 put_device(&rdev->dev);
2243                 return regulator;
2244         }
2245
2246         ret = regulator_resolve_supply(rdev);
2247         if (ret < 0) {
2248                 regulator = ERR_PTR(ret);
2249                 put_device(&rdev->dev);
2250                 return regulator;
2251         }
2252
2253         if (!try_module_get(rdev->owner)) {
2254                 regulator = ERR_PTR(-EPROBE_DEFER);
2255                 put_device(&rdev->dev);
2256                 return regulator;
2257         }
2258
2259         regulator_lock(rdev);
2260         regulator = create_regulator(rdev, dev, id);
2261         regulator_unlock(rdev);
2262         if (regulator == NULL) {
2263                 regulator = ERR_PTR(-ENOMEM);
2264                 module_put(rdev->owner);
2265                 put_device(&rdev->dev);
2266                 return regulator;
2267         }
2268
2269         rdev->open_count++;
2270         if (get_type == EXCLUSIVE_GET) {
2271                 rdev->exclusive = 1;
2272
2273                 ret = _regulator_is_enabled(rdev);
2274                 if (ret > 0) {
2275                         rdev->use_count = 1;
2276                         regulator->enable_count = 1;
2277                 } else {
2278                         rdev->use_count = 0;
2279                         regulator->enable_count = 0;
2280                 }
2281         }
2282
2283         link = device_link_add(dev, &rdev->dev, DL_FLAG_STATELESS);
2284         if (!IS_ERR_OR_NULL(link))
2285                 regulator->device_link = true;
2286
2287         return regulator;
2288 }
2289
2290 /**
2291  * regulator_get - lookup and obtain a reference to a regulator.
2292  * @dev: device for regulator "consumer"
2293  * @id: Supply name or regulator ID.
2294  *
2295  * Returns a struct regulator corresponding to the regulator producer,
2296  * or IS_ERR() condition containing errno.
2297  *
2298  * Use of supply names configured via set_consumer_device_supply() is
2299  * strongly encouraged.  It is recommended that the supply name used
2300  * should match the name used for the supply and/or the relevant
2301  * device pins in the datasheet.
2302  */
2303 struct regulator *regulator_get(struct device *dev, const char *id)
2304 {
2305         return _regulator_get(dev, id, NORMAL_GET);
2306 }
2307 EXPORT_SYMBOL_GPL(regulator_get);
2308
2309 /**
2310  * regulator_get_exclusive - obtain exclusive access to a regulator.
2311  * @dev: device for regulator "consumer"
2312  * @id: Supply name or regulator ID.
2313  *
2314  * Returns a struct regulator corresponding to the regulator producer,
2315  * or IS_ERR() condition containing errno.  Other consumers will be
2316  * unable to obtain this regulator while this reference is held and the
2317  * use count for the regulator will be initialised to reflect the current
2318  * state of the regulator.
2319  *
2320  * This is intended for use by consumers which cannot tolerate shared
2321  * use of the regulator such as those which need to force the
2322  * regulator off for correct operation of the hardware they are
2323  * controlling.
2324  *
2325  * Use of supply names configured via set_consumer_device_supply() is
2326  * strongly encouraged.  It is recommended that the supply name used
2327  * should match the name used for the supply and/or the relevant
2328  * device pins in the datasheet.
2329  */
2330 struct regulator *regulator_get_exclusive(struct device *dev, const char *id)
2331 {
2332         return _regulator_get(dev, id, EXCLUSIVE_GET);
2333 }
2334 EXPORT_SYMBOL_GPL(regulator_get_exclusive);
2335
2336 /**
2337  * regulator_get_optional - obtain optional access to a regulator.
2338  * @dev: device for regulator "consumer"
2339  * @id: Supply name or regulator ID.
2340  *
2341  * Returns a struct regulator corresponding to the regulator producer,
2342  * or IS_ERR() condition containing errno.
2343  *
2344  * This is intended for use by consumers for devices which can have
2345  * some supplies unconnected in normal use, such as some MMC devices.
2346  * It can allow the regulator core to provide stub supplies for other
2347  * supplies requested using normal regulator_get() calls without
2348  * disrupting the operation of drivers that can handle absent
2349  * supplies.
2350  *
2351  * Use of supply names configured via set_consumer_device_supply() is
2352  * strongly encouraged.  It is recommended that the supply name used
2353  * should match the name used for the supply and/or the relevant
2354  * device pins in the datasheet.
2355  */
2356 struct regulator *regulator_get_optional(struct device *dev, const char *id)
2357 {
2358         return _regulator_get(dev, id, OPTIONAL_GET);
2359 }
2360 EXPORT_SYMBOL_GPL(regulator_get_optional);
2361
2362 static void destroy_regulator(struct regulator *regulator)
2363 {
2364         struct regulator_dev *rdev = regulator->rdev;
2365
2366         debugfs_remove_recursive(regulator->debugfs);
2367
2368         if (regulator->dev) {
2369                 if (regulator->device_link)
2370                         device_link_remove(regulator->dev, &rdev->dev);
2371
2372                 /* remove any sysfs entries */
2373                 sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
2374         }
2375
2376         regulator_lock(rdev);
2377         list_del(&regulator->list);
2378
2379         rdev->open_count--;
2380         rdev->exclusive = 0;
2381         regulator_unlock(rdev);
2382
2383         kfree_const(regulator->supply_name);
2384         kfree(regulator);
2385 }
2386
2387 /* regulator_list_mutex lock held by regulator_put() */
2388 static void _regulator_put(struct regulator *regulator)
2389 {
2390         struct regulator_dev *rdev;
2391
2392         if (IS_ERR_OR_NULL(regulator))
2393                 return;
2394
2395         lockdep_assert_held_once(&regulator_list_mutex);
2396
2397         /* Docs say you must disable before calling regulator_put() */
2398         WARN_ON(regulator->enable_count);
2399
2400         rdev = regulator->rdev;
2401
2402         destroy_regulator(regulator);
2403
2404         module_put(rdev->owner);
2405         put_device(&rdev->dev);
2406 }
2407
2408 /**
2409  * regulator_put - "free" the regulator source
2410  * @regulator: regulator source
2411  *
2412  * Note: drivers must ensure that all regulator_enable calls made on this
2413  * regulator source are balanced by regulator_disable calls prior to calling
2414  * this function.
2415  */
2416 void regulator_put(struct regulator *regulator)
2417 {
2418         mutex_lock(&regulator_list_mutex);
2419         _regulator_put(regulator);
2420         mutex_unlock(&regulator_list_mutex);
2421 }
2422 EXPORT_SYMBOL_GPL(regulator_put);
2423
2424 /**
2425  * regulator_register_supply_alias - Provide device alias for supply lookup
2426  *
2427  * @dev: device that will be given as the regulator "consumer"
2428  * @id: Supply name or regulator ID
2429  * @alias_dev: device that should be used to lookup the supply
2430  * @alias_id: Supply name or regulator ID that should be used to lookup the
2431  * supply
2432  *
2433  * All lookups for id on dev will instead be conducted for alias_id on
2434  * alias_dev.
2435  */
2436 int regulator_register_supply_alias(struct device *dev, const char *id,
2437                                     struct device *alias_dev,
2438                                     const char *alias_id)
2439 {
2440         struct regulator_supply_alias *map;
2441
2442         map = regulator_find_supply_alias(dev, id);
2443         if (map)
2444                 return -EEXIST;
2445
2446         map = kzalloc(sizeof(struct regulator_supply_alias), GFP_KERNEL);
2447         if (!map)
2448                 return -ENOMEM;
2449
2450         map->src_dev = dev;
2451         map->src_supply = id;
2452         map->alias_dev = alias_dev;
2453         map->alias_supply = alias_id;
2454
2455         list_add(&map->list, &regulator_supply_alias_list);
2456
2457         pr_info("Adding alias for supply %s,%s -> %s,%s\n",
2458                 id, dev_name(dev), alias_id, dev_name(alias_dev));
2459
2460         return 0;
2461 }
2462 EXPORT_SYMBOL_GPL(regulator_register_supply_alias);
2463
2464 /**
2465  * regulator_unregister_supply_alias - Remove device alias
2466  *
2467  * @dev: device that will be given as the regulator "consumer"
2468  * @id: Supply name or regulator ID
2469  *
2470  * Remove a lookup alias if one exists for id on dev.
2471  */
2472 void regulator_unregister_supply_alias(struct device *dev, const char *id)
2473 {
2474         struct regulator_supply_alias *map;
2475
2476         map = regulator_find_supply_alias(dev, id);
2477         if (map) {
2478                 list_del(&map->list);
2479                 kfree(map);
2480         }
2481 }
2482 EXPORT_SYMBOL_GPL(regulator_unregister_supply_alias);
2483
2484 /**
2485  * regulator_bulk_register_supply_alias - register multiple aliases
2486  *
2487  * @dev: device that will be given as the regulator "consumer"
2488  * @id: List of supply names or regulator IDs
2489  * @alias_dev: device that should be used to lookup the supply
2490  * @alias_id: List of supply names or regulator IDs that should be used to
2491  * lookup the supply
2492  * @num_id: Number of aliases to register
2493  *
2494  * @return 0 on success, an errno on failure.
2495  *
2496  * This helper function allows drivers to register several supply
2497  * aliases in one operation.  If any of the aliases cannot be
2498  * registered any aliases that were registered will be removed
2499  * before returning to the caller.
2500  */
2501 int regulator_bulk_register_supply_alias(struct device *dev,
2502                                          const char *const *id,
2503                                          struct device *alias_dev,
2504                                          const char *const *alias_id,
2505                                          int num_id)
2506 {
2507         int i;
2508         int ret;
2509
2510         for (i = 0; i < num_id; ++i) {
2511                 ret = regulator_register_supply_alias(dev, id[i], alias_dev,
2512                                                       alias_id[i]);
2513                 if (ret < 0)
2514                         goto err;
2515         }
2516
2517         return 0;
2518
2519 err:
2520         dev_err(dev,
2521                 "Failed to create supply alias %s,%s -> %s,%s\n",
2522                 id[i], dev_name(dev), alias_id[i], dev_name(alias_dev));
2523
2524         while (--i >= 0)
2525                 regulator_unregister_supply_alias(dev, id[i]);
2526
2527         return ret;
2528 }
2529 EXPORT_SYMBOL_GPL(regulator_bulk_register_supply_alias);
2530
2531 /**
2532  * regulator_bulk_unregister_supply_alias - unregister multiple aliases
2533  *
2534  * @dev: device that will be given as the regulator "consumer"
2535  * @id: List of supply names or regulator IDs
2536  * @num_id: Number of aliases to unregister
2537  *
2538  * This helper function allows drivers to unregister several supply
2539  * aliases in one operation.
2540  */
2541 void regulator_bulk_unregister_supply_alias(struct device *dev,
2542                                             const char *const *id,
2543                                             int num_id)
2544 {
2545         int i;
2546
2547         for (i = 0; i < num_id; ++i)
2548                 regulator_unregister_supply_alias(dev, id[i]);
2549 }
2550 EXPORT_SYMBOL_GPL(regulator_bulk_unregister_supply_alias);
2551
2552
2553 /* Manage enable GPIO list. Same GPIO pin can be shared among regulators */
2554 static int regulator_ena_gpio_request(struct regulator_dev *rdev,
2555                                 const struct regulator_config *config)
2556 {
2557         struct regulator_enable_gpio *pin, *new_pin;
2558         struct gpio_desc *gpiod;
2559
2560         gpiod = config->ena_gpiod;
2561         new_pin = kzalloc(sizeof(*new_pin), GFP_KERNEL);
2562
2563         mutex_lock(&regulator_list_mutex);
2564
2565         list_for_each_entry(pin, &regulator_ena_gpio_list, list) {
2566                 if (pin->gpiod == gpiod) {
2567                         rdev_dbg(rdev, "GPIO is already used\n");
2568                         goto update_ena_gpio_to_rdev;
2569                 }
2570         }
2571
2572         if (new_pin == NULL) {
2573                 mutex_unlock(&regulator_list_mutex);
2574                 return -ENOMEM;
2575         }
2576
2577         pin = new_pin;
2578         new_pin = NULL;
2579
2580         pin->gpiod = gpiod;
2581         list_add(&pin->list, &regulator_ena_gpio_list);
2582
2583 update_ena_gpio_to_rdev:
2584         pin->request_count++;
2585         rdev->ena_pin = pin;
2586
2587         mutex_unlock(&regulator_list_mutex);
2588         kfree(new_pin);
2589
2590         return 0;
2591 }
2592
2593 static void regulator_ena_gpio_free(struct regulator_dev *rdev)
2594 {
2595         struct regulator_enable_gpio *pin, *n;
2596
2597         if (!rdev->ena_pin)
2598                 return;
2599
2600         /* Free the GPIO only in case of no use */
2601         list_for_each_entry_safe(pin, n, &regulator_ena_gpio_list, list) {
2602                 if (pin != rdev->ena_pin)
2603                         continue;
2604
2605                 if (--pin->request_count)
2606                         break;
2607
2608                 gpiod_put(pin->gpiod);
2609                 list_del(&pin->list);
2610                 kfree(pin);
2611                 break;
2612         }
2613
2614         rdev->ena_pin = NULL;
2615 }
2616
2617 /**
2618  * regulator_ena_gpio_ctrl - balance enable_count of each GPIO and actual GPIO pin control
2619  * @rdev: regulator_dev structure
2620  * @enable: enable GPIO at initial use?
2621  *
2622  * GPIO is enabled in case of initial use. (enable_count is 0)
2623  * GPIO is disabled when it is not shared any more. (enable_count <= 1)
2624  */
2625 static int regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable)
2626 {
2627         struct regulator_enable_gpio *pin = rdev->ena_pin;
2628
2629         if (!pin)
2630                 return -EINVAL;
2631
2632         if (enable) {
2633                 /* Enable GPIO at initial use */
2634                 if (pin->enable_count == 0)
2635                         gpiod_set_value_cansleep(pin->gpiod, 1);
2636
2637                 pin->enable_count++;
2638         } else {
2639                 if (pin->enable_count > 1) {
2640                         pin->enable_count--;
2641                         return 0;
2642                 }
2643
2644                 /* Disable GPIO if not used */
2645                 if (pin->enable_count <= 1) {
2646                         gpiod_set_value_cansleep(pin->gpiod, 0);
2647                         pin->enable_count = 0;
2648                 }
2649         }
2650
2651         return 0;
2652 }
2653
2654 /**
2655  * _regulator_delay_helper - a delay helper function
2656  * @delay: time to delay in microseconds
2657  *
2658  * Delay for the requested amount of time as per the guidelines in:
2659  *
2660  *     Documentation/timers/timers-howto.rst
2661  *
2662  * The assumption here is that these regulator operations will never used in
2663  * atomic context and therefore sleeping functions can be used.
2664  */
2665 static void _regulator_delay_helper(unsigned int delay)
2666 {
2667         unsigned int ms = delay / 1000;
2668         unsigned int us = delay % 1000;
2669
2670         if (ms > 0) {
2671                 /*
2672                  * For small enough values, handle super-millisecond
2673                  * delays in the usleep_range() call below.
2674                  */
2675                 if (ms < 20)
2676                         us += ms * 1000;
2677                 else
2678                         msleep(ms);
2679         }
2680
2681         /*
2682          * Give the scheduler some room to coalesce with any other
2683          * wakeup sources. For delays shorter than 10 us, don't even
2684          * bother setting up high-resolution timers and just busy-
2685          * loop.
2686          */
2687         if (us >= 10)
2688                 usleep_range(us, us + 100);
2689         else
2690                 udelay(us);
2691 }
2692
2693 /**
2694  * _regulator_check_status_enabled
2695  *
2696  * A helper function to check if the regulator status can be interpreted
2697  * as 'regulator is enabled'.
2698  * @rdev: the regulator device to check
2699  *
2700  * Return:
2701  * * 1                  - if status shows regulator is in enabled state
2702  * * 0                  - if not enabled state
2703  * * Error Value        - as received from ops->get_status()
2704  */
2705 static inline int _regulator_check_status_enabled(struct regulator_dev *rdev)
2706 {
2707         int ret = rdev->desc->ops->get_status(rdev);
2708
2709         if (ret < 0) {
2710                 rdev_info(rdev, "get_status returned error: %d\n", ret);
2711                 return ret;
2712         }
2713
2714         switch (ret) {
2715         case REGULATOR_STATUS_OFF:
2716         case REGULATOR_STATUS_ERROR:
2717         case REGULATOR_STATUS_UNDEFINED:
2718                 return 0;
2719         default:
2720                 return 1;
2721         }
2722 }
2723
2724 static int _regulator_do_enable(struct regulator_dev *rdev)
2725 {
2726         int ret, delay;
2727
2728         /* Query before enabling in case configuration dependent.  */
2729         ret = _regulator_get_enable_time(rdev);
2730         if (ret >= 0) {
2731                 delay = ret;
2732         } else {
2733                 rdev_warn(rdev, "enable_time() failed: %pe\n", ERR_PTR(ret));
2734                 delay = 0;
2735         }
2736
2737         trace_regulator_enable(rdev_get_name(rdev));
2738
2739         if (rdev->desc->off_on_delay) {
2740                 /* if needed, keep a distance of off_on_delay from last time
2741                  * this regulator was disabled.
2742                  */
2743                 ktime_t end = ktime_add_us(rdev->last_off, rdev->desc->off_on_delay);
2744                 s64 remaining = ktime_us_delta(end, ktime_get_boottime());
2745
2746                 if (remaining > 0)
2747                         _regulator_delay_helper(remaining);
2748         }
2749
2750         if (rdev->ena_pin) {
2751                 if (!rdev->ena_gpio_state) {
2752                         ret = regulator_ena_gpio_ctrl(rdev, true);
2753                         if (ret < 0)
2754                                 return ret;
2755                         rdev->ena_gpio_state = 1;
2756                 }
2757         } else if (rdev->desc->ops->enable) {
2758                 ret = rdev->desc->ops->enable(rdev);
2759                 if (ret < 0)
2760                         return ret;
2761         } else {
2762                 return -EINVAL;
2763         }
2764
2765         /* Allow the regulator to ramp; it would be useful to extend
2766          * this for bulk operations so that the regulators can ramp
2767          * together.
2768          */
2769         trace_regulator_enable_delay(rdev_get_name(rdev));
2770
2771         /* If poll_enabled_time is set, poll upto the delay calculated
2772          * above, delaying poll_enabled_time uS to check if the regulator
2773          * actually got enabled.
2774          * If the regulator isn't enabled after our delay helper has expired,
2775          * return -ETIMEDOUT.
2776          */
2777         if (rdev->desc->poll_enabled_time) {
2778                 int time_remaining = delay;
2779
2780                 while (time_remaining > 0) {
2781                         _regulator_delay_helper(rdev->desc->poll_enabled_time);
2782
2783                         if (rdev->desc->ops->get_status) {
2784                                 ret = _regulator_check_status_enabled(rdev);
2785                                 if (ret < 0)
2786                                         return ret;
2787                                 else if (ret)
2788                                         break;
2789                         } else if (rdev->desc->ops->is_enabled(rdev))
2790                                 break;
2791
2792                         time_remaining -= rdev->desc->poll_enabled_time;
2793                 }
2794
2795                 if (time_remaining <= 0) {
2796                         rdev_err(rdev, "Enabled check timed out\n");
2797                         return -ETIMEDOUT;
2798                 }
2799         } else {
2800                 _regulator_delay_helper(delay);
2801         }
2802
2803         trace_regulator_enable_complete(rdev_get_name(rdev));
2804
2805         return 0;
2806 }
2807
2808 /**
2809  * _regulator_handle_consumer_enable - handle that a consumer enabled
2810  * @regulator: regulator source
2811  *
2812  * Some things on a regulator consumer (like the contribution towards total
2813  * load on the regulator) only have an effect when the consumer wants the
2814  * regulator enabled.  Explained in example with two consumers of the same
2815  * regulator:
2816  *   consumer A: set_load(100);       => total load = 0
2817  *   consumer A: regulator_enable();  => total load = 100
2818  *   consumer B: set_load(1000);      => total load = 100
2819  *   consumer B: regulator_enable();  => total load = 1100
2820  *   consumer A: regulator_disable(); => total_load = 1000
2821  *
2822  * This function (together with _regulator_handle_consumer_disable) is
2823  * responsible for keeping track of the refcount for a given regulator consumer
2824  * and applying / unapplying these things.
2825  *
2826  * Returns 0 upon no error; -error upon error.
2827  */
2828 static int _regulator_handle_consumer_enable(struct regulator *regulator)
2829 {
2830         int ret;
2831         struct regulator_dev *rdev = regulator->rdev;
2832
2833         lockdep_assert_held_once(&rdev->mutex.base);
2834
2835         regulator->enable_count++;
2836         if (regulator->uA_load && regulator->enable_count == 1) {
2837                 ret = drms_uA_update(rdev);
2838                 if (ret)
2839                         regulator->enable_count--;
2840                 return ret;
2841         }
2842
2843         return 0;
2844 }
2845
2846 /**
2847  * _regulator_handle_consumer_disable - handle that a consumer disabled
2848  * @regulator: regulator source
2849  *
2850  * The opposite of _regulator_handle_consumer_enable().
2851  *
2852  * Returns 0 upon no error; -error upon error.
2853  */
2854 static int _regulator_handle_consumer_disable(struct regulator *regulator)
2855 {
2856         struct regulator_dev *rdev = regulator->rdev;
2857
2858         lockdep_assert_held_once(&rdev->mutex.base);
2859
2860         if (!regulator->enable_count) {
2861                 rdev_err(rdev, "Underflow of regulator enable count\n");
2862                 return -EINVAL;
2863         }
2864
2865         regulator->enable_count--;
2866         if (regulator->uA_load && regulator->enable_count == 0)
2867                 return drms_uA_update(rdev);
2868
2869         return 0;
2870 }
2871
2872 /* locks held by regulator_enable() */
2873 static int _regulator_enable(struct regulator *regulator)
2874 {
2875         struct regulator_dev *rdev = regulator->rdev;
2876         int ret;
2877
2878         lockdep_assert_held_once(&rdev->mutex.base);
2879
2880         if (rdev->use_count == 0 && rdev->supply) {
2881                 ret = _regulator_enable(rdev->supply);
2882                 if (ret < 0)
2883                         return ret;
2884         }
2885
2886         /* balance only if there are regulators coupled */
2887         if (rdev->coupling_desc.n_coupled > 1) {
2888                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
2889                 if (ret < 0)
2890                         goto err_disable_supply;
2891         }
2892
2893         ret = _regulator_handle_consumer_enable(regulator);
2894         if (ret < 0)
2895                 goto err_disable_supply;
2896
2897         if (rdev->use_count == 0) {
2898                 /*
2899                  * The regulator may already be enabled if it's not switchable
2900                  * or was left on
2901                  */
2902                 ret = _regulator_is_enabled(rdev);
2903                 if (ret == -EINVAL || ret == 0) {
2904                         if (!regulator_ops_is_valid(rdev,
2905                                         REGULATOR_CHANGE_STATUS)) {
2906                                 ret = -EPERM;
2907                                 goto err_consumer_disable;
2908                         }
2909
2910                         ret = _regulator_do_enable(rdev);
2911                         if (ret < 0)
2912                                 goto err_consumer_disable;
2913
2914                         _notifier_call_chain(rdev, REGULATOR_EVENT_ENABLE,
2915                                              NULL);
2916                 } else if (ret < 0) {
2917                         rdev_err(rdev, "is_enabled() failed: %pe\n", ERR_PTR(ret));
2918                         goto err_consumer_disable;
2919                 }
2920                 /* Fallthrough on positive return values - already enabled */
2921         }
2922
2923         if (regulator->enable_count == 1)
2924                 rdev->use_count++;
2925
2926         return 0;
2927
2928 err_consumer_disable:
2929         _regulator_handle_consumer_disable(regulator);
2930
2931 err_disable_supply:
2932         if (rdev->use_count == 0 && rdev->supply)
2933                 _regulator_disable(rdev->supply);
2934
2935         return ret;
2936 }
2937
2938 /**
2939  * regulator_enable - enable regulator output
2940  * @regulator: regulator source
2941  *
2942  * Request that the regulator be enabled with the regulator output at
2943  * the predefined voltage or current value.  Calls to regulator_enable()
2944  * must be balanced with calls to regulator_disable().
2945  *
2946  * NOTE: the output value can be set by other drivers, boot loader or may be
2947  * hardwired in the regulator.
2948  */
2949 int regulator_enable(struct regulator *regulator)
2950 {
2951         struct regulator_dev *rdev = regulator->rdev;
2952         struct ww_acquire_ctx ww_ctx;
2953         int ret;
2954
2955         regulator_lock_dependent(rdev, &ww_ctx);
2956         ret = _regulator_enable(regulator);
2957         regulator_unlock_dependent(rdev, &ww_ctx);
2958
2959         return ret;
2960 }
2961 EXPORT_SYMBOL_GPL(regulator_enable);
2962
2963 static int _regulator_do_disable(struct regulator_dev *rdev)
2964 {
2965         int ret;
2966
2967         trace_regulator_disable(rdev_get_name(rdev));
2968
2969         if (rdev->ena_pin) {
2970                 if (rdev->ena_gpio_state) {
2971                         ret = regulator_ena_gpio_ctrl(rdev, false);
2972                         if (ret < 0)
2973                                 return ret;
2974                         rdev->ena_gpio_state = 0;
2975                 }
2976
2977         } else if (rdev->desc->ops->disable) {
2978                 ret = rdev->desc->ops->disable(rdev);
2979                 if (ret != 0)
2980                         return ret;
2981         }
2982
2983         if (rdev->desc->off_on_delay)
2984                 rdev->last_off = ktime_get_boottime();
2985
2986         trace_regulator_disable_complete(rdev_get_name(rdev));
2987
2988         return 0;
2989 }
2990
2991 /* locks held by regulator_disable() */
2992 static int _regulator_disable(struct regulator *regulator)
2993 {
2994         struct regulator_dev *rdev = regulator->rdev;
2995         int ret = 0;
2996
2997         lockdep_assert_held_once(&rdev->mutex.base);
2998
2999         if (WARN(regulator->enable_count == 0,
3000                  "unbalanced disables for %s\n", rdev_get_name(rdev)))
3001                 return -EIO;
3002
3003         if (regulator->enable_count == 1) {
3004         /* disabling last enable_count from this regulator */
3005                 /* are we the last user and permitted to disable ? */
3006                 if (rdev->use_count == 1 &&
3007                     (rdev->constraints && !rdev->constraints->always_on)) {
3008
3009                         /* we are last user */
3010                         if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
3011                                 ret = _notifier_call_chain(rdev,
3012                                                            REGULATOR_EVENT_PRE_DISABLE,
3013                                                            NULL);
3014                                 if (ret & NOTIFY_STOP_MASK)
3015                                         return -EINVAL;
3016
3017                                 ret = _regulator_do_disable(rdev);
3018                                 if (ret < 0) {
3019                                         rdev_err(rdev, "failed to disable: %pe\n", ERR_PTR(ret));
3020                                         _notifier_call_chain(rdev,
3021                                                         REGULATOR_EVENT_ABORT_DISABLE,
3022                                                         NULL);
3023                                         return ret;
3024                                 }
3025                                 _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
3026                                                 NULL);
3027                         }
3028
3029                         rdev->use_count = 0;
3030                 } else if (rdev->use_count > 1) {
3031                         rdev->use_count--;
3032                 }
3033         }
3034
3035         if (ret == 0)
3036                 ret = _regulator_handle_consumer_disable(regulator);
3037
3038         if (ret == 0 && rdev->coupling_desc.n_coupled > 1)
3039                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3040
3041         if (ret == 0 && rdev->use_count == 0 && rdev->supply)
3042                 ret = _regulator_disable(rdev->supply);
3043
3044         return ret;
3045 }
3046
3047 /**
3048  * regulator_disable - disable regulator output
3049  * @regulator: regulator source
3050  *
3051  * Disable the regulator output voltage or current.  Calls to
3052  * regulator_enable() must be balanced with calls to
3053  * regulator_disable().
3054  *
3055  * NOTE: this will only disable the regulator output if no other consumer
3056  * devices have it enabled, the regulator device supports disabling and
3057  * machine constraints permit this operation.
3058  */
3059 int regulator_disable(struct regulator *regulator)
3060 {
3061         struct regulator_dev *rdev = regulator->rdev;
3062         struct ww_acquire_ctx ww_ctx;
3063         int ret;
3064
3065         regulator_lock_dependent(rdev, &ww_ctx);
3066         ret = _regulator_disable(regulator);
3067         regulator_unlock_dependent(rdev, &ww_ctx);
3068
3069         return ret;
3070 }
3071 EXPORT_SYMBOL_GPL(regulator_disable);
3072
3073 /* locks held by regulator_force_disable() */
3074 static int _regulator_force_disable(struct regulator_dev *rdev)
3075 {
3076         int ret = 0;
3077
3078         lockdep_assert_held_once(&rdev->mutex.base);
3079
3080         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3081                         REGULATOR_EVENT_PRE_DISABLE, NULL);
3082         if (ret & NOTIFY_STOP_MASK)
3083                 return -EINVAL;
3084
3085         ret = _regulator_do_disable(rdev);
3086         if (ret < 0) {
3087                 rdev_err(rdev, "failed to force disable: %pe\n", ERR_PTR(ret));
3088                 _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3089                                 REGULATOR_EVENT_ABORT_DISABLE, NULL);
3090                 return ret;
3091         }
3092
3093         _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE |
3094                         REGULATOR_EVENT_DISABLE, NULL);
3095
3096         return 0;
3097 }
3098
3099 /**
3100  * regulator_force_disable - force disable regulator output
3101  * @regulator: regulator source
3102  *
3103  * Forcibly disable the regulator output voltage or current.
3104  * NOTE: this *will* disable the regulator output even if other consumer
3105  * devices have it enabled. This should be used for situations when device
3106  * damage will likely occur if the regulator is not disabled (e.g. over temp).
3107  */
3108 int regulator_force_disable(struct regulator *regulator)
3109 {
3110         struct regulator_dev *rdev = regulator->rdev;
3111         struct ww_acquire_ctx ww_ctx;
3112         int ret;
3113
3114         regulator_lock_dependent(rdev, &ww_ctx);
3115
3116         ret = _regulator_force_disable(regulator->rdev);
3117
3118         if (rdev->coupling_desc.n_coupled > 1)
3119                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3120
3121         if (regulator->uA_load) {
3122                 regulator->uA_load = 0;
3123                 ret = drms_uA_update(rdev);
3124         }
3125
3126         if (rdev->use_count != 0 && rdev->supply)
3127                 _regulator_disable(rdev->supply);
3128
3129         regulator_unlock_dependent(rdev, &ww_ctx);
3130
3131         return ret;
3132 }
3133 EXPORT_SYMBOL_GPL(regulator_force_disable);
3134
3135 static void regulator_disable_work(struct work_struct *work)
3136 {
3137         struct regulator_dev *rdev = container_of(work, struct regulator_dev,
3138                                                   disable_work.work);
3139         struct ww_acquire_ctx ww_ctx;
3140         int count, i, ret;
3141         struct regulator *regulator;
3142         int total_count = 0;
3143
3144         regulator_lock_dependent(rdev, &ww_ctx);
3145
3146         /*
3147          * Workqueue functions queue the new work instance while the previous
3148          * work instance is being processed. Cancel the queued work instance
3149          * as the work instance under processing does the job of the queued
3150          * work instance.
3151          */
3152         cancel_delayed_work(&rdev->disable_work);
3153
3154         list_for_each_entry(regulator, &rdev->consumer_list, list) {
3155                 count = regulator->deferred_disables;
3156
3157                 if (!count)
3158                         continue;
3159
3160                 total_count += count;
3161                 regulator->deferred_disables = 0;
3162
3163                 for (i = 0; i < count; i++) {
3164                         ret = _regulator_disable(regulator);
3165                         if (ret != 0)
3166                                 rdev_err(rdev, "Deferred disable failed: %pe\n",
3167                                          ERR_PTR(ret));
3168                 }
3169         }
3170         WARN_ON(!total_count);
3171
3172         if (rdev->coupling_desc.n_coupled > 1)
3173                 regulator_balance_voltage(rdev, PM_SUSPEND_ON);
3174
3175         regulator_unlock_dependent(rdev, &ww_ctx);
3176 }
3177
3178 /**
3179  * regulator_disable_deferred - disable regulator output with delay
3180  * @regulator: regulator source
3181  * @ms: milliseconds until the regulator is disabled
3182  *
3183  * Execute regulator_disable() on the regulator after a delay.  This
3184  * is intended for use with devices that require some time to quiesce.
3185  *
3186  * NOTE: this will only disable the regulator output if no other consumer
3187  * devices have it enabled, the regulator device supports disabling and
3188  * machine constraints permit this operation.
3189  */
3190 int regulator_disable_deferred(struct regulator *regulator, int ms)
3191 {
3192         struct regulator_dev *rdev = regulator->rdev;
3193
3194         if (!ms)
3195                 return regulator_disable(regulator);
3196
3197         regulator_lock(rdev);
3198         regulator->deferred_disables++;
3199         mod_delayed_work(system_power_efficient_wq, &rdev->disable_work,
3200                          msecs_to_jiffies(ms));
3201         regulator_unlock(rdev);
3202
3203         return 0;
3204 }
3205 EXPORT_SYMBOL_GPL(regulator_disable_deferred);
3206
3207 static int _regulator_is_enabled(struct regulator_dev *rdev)
3208 {
3209         /* A GPIO control always takes precedence */
3210         if (rdev->ena_pin)
3211                 return rdev->ena_gpio_state;
3212
3213         /* If we don't know then assume that the regulator is always on */
3214         if (!rdev->desc->ops->is_enabled)
3215                 return 1;
3216
3217         return rdev->desc->ops->is_enabled(rdev);
3218 }
3219
3220 static int _regulator_list_voltage(struct regulator_dev *rdev,
3221                                    unsigned selector, int lock)
3222 {
3223         const struct regulator_ops *ops = rdev->desc->ops;
3224         int ret;
3225
3226         if (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1 && !selector)
3227                 return rdev->desc->fixed_uV;
3228
3229         if (ops->list_voltage) {
3230                 if (selector >= rdev->desc->n_voltages)
3231                         return -EINVAL;
3232                 if (selector < rdev->desc->linear_min_sel)
3233                         return 0;
3234                 if (lock)
3235                         regulator_lock(rdev);
3236                 ret = ops->list_voltage(rdev, selector);
3237                 if (lock)
3238                         regulator_unlock(rdev);
3239         } else if (rdev->is_switch && rdev->supply) {
3240                 ret = _regulator_list_voltage(rdev->supply->rdev,
3241                                               selector, lock);
3242         } else {
3243                 return -EINVAL;
3244         }
3245
3246         if (ret > 0) {
3247                 if (ret < rdev->constraints->min_uV)
3248                         ret = 0;
3249                 else if (ret > rdev->constraints->max_uV)
3250                         ret = 0;
3251         }
3252
3253         return ret;
3254 }
3255
3256 /**
3257  * regulator_is_enabled - is the regulator output enabled
3258  * @regulator: regulator source
3259  *
3260  * Returns positive if the regulator driver backing the source/client
3261  * has requested that the device be enabled, zero if it hasn't, else a
3262  * negative errno code.
3263  *
3264  * Note that the device backing this regulator handle can have multiple
3265  * users, so it might be enabled even if regulator_enable() was never
3266  * called for this particular source.
3267  */
3268 int regulator_is_enabled(struct regulator *regulator)
3269 {
3270         int ret;
3271
3272         if (regulator->always_on)
3273                 return 1;
3274
3275         regulator_lock(regulator->rdev);
3276         ret = _regulator_is_enabled(regulator->rdev);
3277         regulator_unlock(regulator->rdev);
3278
3279         return ret;
3280 }
3281 EXPORT_SYMBOL_GPL(regulator_is_enabled);
3282
3283 /**
3284  * regulator_count_voltages - count regulator_list_voltage() selectors
3285  * @regulator: regulator source
3286  *
3287  * Returns number of selectors, or negative errno.  Selectors are
3288  * numbered starting at zero, and typically correspond to bitfields
3289  * in hardware registers.
3290  */
3291 int regulator_count_voltages(struct regulator *regulator)
3292 {
3293         struct regulator_dev    *rdev = regulator->rdev;
3294
3295         if (rdev->desc->n_voltages)
3296                 return rdev->desc->n_voltages;
3297
3298         if (!rdev->is_switch || !rdev->supply)
3299                 return -EINVAL;
3300
3301         return regulator_count_voltages(rdev->supply);
3302 }
3303 EXPORT_SYMBOL_GPL(regulator_count_voltages);
3304
3305 /**
3306  * regulator_list_voltage - enumerate supported voltages
3307  * @regulator: regulator source
3308  * @selector: identify voltage to list
3309  * Context: can sleep
3310  *
3311  * Returns a voltage that can be passed to @regulator_set_voltage(),
3312  * zero if this selector code can't be used on this system, or a
3313  * negative errno.
3314  */
3315 int regulator_list_voltage(struct regulator *regulator, unsigned selector)
3316 {
3317         return _regulator_list_voltage(regulator->rdev, selector, 1);
3318 }
3319 EXPORT_SYMBOL_GPL(regulator_list_voltage);
3320
3321 /**
3322  * regulator_get_regmap - get the regulator's register map
3323  * @regulator: regulator source
3324  *
3325  * Returns the register map for the given regulator, or an ERR_PTR value
3326  * if the regulator doesn't use regmap.
3327  */
3328 struct regmap *regulator_get_regmap(struct regulator *regulator)
3329 {
3330         struct regmap *map = regulator->rdev->regmap;
3331
3332         return map ? map : ERR_PTR(-EOPNOTSUPP);
3333 }
3334
3335 /**
3336  * regulator_get_hardware_vsel_register - get the HW voltage selector register
3337  * @regulator: regulator source
3338  * @vsel_reg: voltage selector register, output parameter
3339  * @vsel_mask: mask for voltage selector bitfield, output parameter
3340  *
3341  * Returns the hardware register offset and bitmask used for setting the
3342  * regulator voltage. This might be useful when configuring voltage-scaling
3343  * hardware or firmware that can make I2C requests behind the kernel's back,
3344  * for example.
3345  *
3346  * On success, the output parameters @vsel_reg and @vsel_mask are filled in
3347  * and 0 is returned, otherwise a negative errno is returned.
3348  */
3349 int regulator_get_hardware_vsel_register(struct regulator *regulator,
3350                                          unsigned *vsel_reg,
3351                                          unsigned *vsel_mask)
3352 {
3353         struct regulator_dev *rdev = regulator->rdev;
3354         const struct regulator_ops *ops = rdev->desc->ops;
3355
3356         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3357                 return -EOPNOTSUPP;
3358
3359         *vsel_reg = rdev->desc->vsel_reg;
3360         *vsel_mask = rdev->desc->vsel_mask;
3361
3362         return 0;
3363 }
3364 EXPORT_SYMBOL_GPL(regulator_get_hardware_vsel_register);
3365
3366 /**
3367  * regulator_list_hardware_vsel - get the HW-specific register value for a selector
3368  * @regulator: regulator source
3369  * @selector: identify voltage to list
3370  *
3371  * Converts the selector to a hardware-specific voltage selector that can be
3372  * directly written to the regulator registers. The address of the voltage
3373  * register can be determined by calling @regulator_get_hardware_vsel_register.
3374  *
3375  * On error a negative errno is returned.
3376  */
3377 int regulator_list_hardware_vsel(struct regulator *regulator,
3378                                  unsigned selector)
3379 {
3380         struct regulator_dev *rdev = regulator->rdev;
3381         const struct regulator_ops *ops = rdev->desc->ops;
3382
3383         if (selector >= rdev->desc->n_voltages)
3384                 return -EINVAL;
3385         if (selector < rdev->desc->linear_min_sel)
3386                 return 0;
3387         if (ops->set_voltage_sel != regulator_set_voltage_sel_regmap)
3388                 return -EOPNOTSUPP;
3389
3390         return selector;
3391 }
3392 EXPORT_SYMBOL_GPL(regulator_list_hardware_vsel);
3393
3394 /**
3395  * regulator_get_linear_step - return the voltage step size between VSEL values
3396  * @regulator: regulator source
3397  *
3398  * Returns the voltage step size between VSEL values for linear
3399  * regulators, or return 0 if the regulator isn't a linear regulator.
3400  */
3401 unsigned int regulator_get_linear_step(struct regulator *regulator)
3402 {
3403         struct regulator_dev *rdev = regulator->rdev;
3404
3405         return rdev->desc->uV_step;
3406 }
3407 EXPORT_SYMBOL_GPL(regulator_get_linear_step);
3408
3409 /**
3410  * regulator_is_supported_voltage - check if a voltage range can be supported
3411  *
3412  * @regulator: Regulator to check.
3413  * @min_uV: Minimum required voltage in uV.
3414  * @max_uV: Maximum required voltage in uV.
3415  *
3416  * Returns a boolean.
3417  */
3418 int regulator_is_supported_voltage(struct regulator *regulator,
3419                                    int min_uV, int max_uV)
3420 {
3421         struct regulator_dev *rdev = regulator->rdev;
3422         int i, voltages, ret;
3423
3424         /* If we can't change voltage check the current voltage */
3425         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3426                 ret = regulator_get_voltage(regulator);
3427                 if (ret >= 0)
3428                         return min_uV <= ret && ret <= max_uV;
3429                 else
3430                         return ret;
3431         }
3432
3433         /* Any voltage within constrains range is fine? */
3434         if (rdev->desc->continuous_voltage_range)
3435                 return min_uV >= rdev->constraints->min_uV &&
3436                                 max_uV <= rdev->constraints->max_uV;
3437
3438         ret = regulator_count_voltages(regulator);
3439         if (ret < 0)
3440                 return 0;
3441         voltages = ret;
3442
3443         for (i = 0; i < voltages; i++) {
3444                 ret = regulator_list_voltage(regulator, i);
3445
3446                 if (ret >= min_uV && ret <= max_uV)
3447                         return 1;
3448         }
3449
3450         return 0;
3451 }
3452 EXPORT_SYMBOL_GPL(regulator_is_supported_voltage);
3453
3454 static int regulator_map_voltage(struct regulator_dev *rdev, int min_uV,
3455                                  int max_uV)
3456 {
3457         const struct regulator_desc *desc = rdev->desc;
3458
3459         if (desc->ops->map_voltage)
3460                 return desc->ops->map_voltage(rdev, min_uV, max_uV);
3461
3462         if (desc->ops->list_voltage == regulator_list_voltage_linear)
3463                 return regulator_map_voltage_linear(rdev, min_uV, max_uV);
3464
3465         if (desc->ops->list_voltage == regulator_list_voltage_linear_range)
3466                 return regulator_map_voltage_linear_range(rdev, min_uV, max_uV);
3467
3468         if (desc->ops->list_voltage ==
3469                 regulator_list_voltage_pickable_linear_range)
3470                 return regulator_map_voltage_pickable_linear_range(rdev,
3471                                                         min_uV, max_uV);
3472
3473         return regulator_map_voltage_iterate(rdev, min_uV, max_uV);
3474 }
3475
3476 static int _regulator_call_set_voltage(struct regulator_dev *rdev,
3477                                        int min_uV, int max_uV,
3478                                        unsigned *selector)
3479 {
3480         struct pre_voltage_change_data data;
3481         int ret;
3482
3483         data.old_uV = regulator_get_voltage_rdev(rdev);
3484         data.min_uV = min_uV;
3485         data.max_uV = max_uV;
3486         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3487                                    &data);
3488         if (ret & NOTIFY_STOP_MASK)
3489                 return -EINVAL;
3490
3491         ret = rdev->desc->ops->set_voltage(rdev, min_uV, max_uV, selector);
3492         if (ret >= 0)
3493                 return ret;
3494
3495         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3496                              (void *)data.old_uV);
3497
3498         return ret;
3499 }
3500
3501 static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev,
3502                                            int uV, unsigned selector)
3503 {
3504         struct pre_voltage_change_data data;
3505         int ret;
3506
3507         data.old_uV = regulator_get_voltage_rdev(rdev);
3508         data.min_uV = uV;
3509         data.max_uV = uV;
3510         ret = _notifier_call_chain(rdev, REGULATOR_EVENT_PRE_VOLTAGE_CHANGE,
3511                                    &data);
3512         if (ret & NOTIFY_STOP_MASK)
3513                 return -EINVAL;
3514
3515         ret = rdev->desc->ops->set_voltage_sel(rdev, selector);
3516         if (ret >= 0)
3517                 return ret;
3518
3519         _notifier_call_chain(rdev, REGULATOR_EVENT_ABORT_VOLTAGE_CHANGE,
3520                              (void *)data.old_uV);
3521
3522         return ret;
3523 }
3524
3525 static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev,
3526                                            int uV, int new_selector)
3527 {
3528         const struct regulator_ops *ops = rdev->desc->ops;
3529         int diff, old_sel, curr_sel, ret;
3530
3531         /* Stepping is only needed if the regulator is enabled. */
3532         if (!_regulator_is_enabled(rdev))
3533                 goto final_set;
3534
3535         if (!ops->get_voltage_sel)
3536                 return -EINVAL;
3537
3538         old_sel = ops->get_voltage_sel(rdev);
3539         if (old_sel < 0)
3540                 return old_sel;
3541
3542         diff = new_selector - old_sel;
3543         if (diff == 0)
3544                 return 0; /* No change needed. */
3545
3546         if (diff > 0) {
3547                 /* Stepping up. */
3548                 for (curr_sel = old_sel + rdev->desc->vsel_step;
3549                      curr_sel < new_selector;
3550                      curr_sel += rdev->desc->vsel_step) {
3551                         /*
3552                          * Call the callback directly instead of using
3553                          * _regulator_call_set_voltage_sel() as we don't
3554                          * want to notify anyone yet. Same in the branch
3555                          * below.
3556                          */
3557                         ret = ops->set_voltage_sel(rdev, curr_sel);
3558                         if (ret)
3559                                 goto try_revert;
3560                 }
3561         } else {
3562                 /* Stepping down. */
3563                 for (curr_sel = old_sel - rdev->desc->vsel_step;
3564                      curr_sel > new_selector;
3565                      curr_sel -= rdev->desc->vsel_step) {
3566                         ret = ops->set_voltage_sel(rdev, curr_sel);
3567                         if (ret)
3568                                 goto try_revert;
3569                 }
3570         }
3571
3572 final_set:
3573         /* The final selector will trigger the notifiers. */
3574         return _regulator_call_set_voltage_sel(rdev, uV, new_selector);
3575
3576 try_revert:
3577         /*
3578          * At least try to return to the previous voltage if setting a new
3579          * one failed.
3580          */
3581         (void)ops->set_voltage_sel(rdev, old_sel);
3582         return ret;
3583 }
3584
3585 static int _regulator_set_voltage_time(struct regulator_dev *rdev,
3586                                        int old_uV, int new_uV)
3587 {
3588         unsigned int ramp_delay = 0;
3589
3590         if (rdev->constraints->ramp_delay)
3591                 ramp_delay = rdev->constraints->ramp_delay;
3592         else if (rdev->desc->ramp_delay)
3593                 ramp_delay = rdev->desc->ramp_delay;
3594         else if (rdev->constraints->settling_time)
3595                 return rdev->constraints->settling_time;
3596         else if (rdev->constraints->settling_time_up &&
3597                  (new_uV > old_uV))
3598                 return rdev->constraints->settling_time_up;
3599         else if (rdev->constraints->settling_time_down &&
3600                  (new_uV < old_uV))
3601                 return rdev->constraints->settling_time_down;
3602
3603         if (ramp_delay == 0)
3604                 return 0;
3605
3606         return DIV_ROUND_UP(abs(new_uV - old_uV), ramp_delay);
3607 }
3608
3609 static int _regulator_do_set_voltage(struct regulator_dev *rdev,
3610                                      int min_uV, int max_uV)
3611 {
3612         int ret;
3613         int delay = 0;
3614         int best_val = 0;
3615         unsigned int selector;
3616         int old_selector = -1;
3617         const struct regulator_ops *ops = rdev->desc->ops;
3618         int old_uV = regulator_get_voltage_rdev(rdev);
3619
3620         trace_regulator_set_voltage(rdev_get_name(rdev), min_uV, max_uV);
3621
3622         min_uV += rdev->constraints->uV_offset;
3623         max_uV += rdev->constraints->uV_offset;
3624
3625         /*
3626          * If we can't obtain the old selector there is not enough
3627          * info to call set_voltage_time_sel().
3628          */
3629         if (_regulator_is_enabled(rdev) &&
3630             ops->set_voltage_time_sel && ops->get_voltage_sel) {
3631                 old_selector = ops->get_voltage_sel(rdev);
3632                 if (old_selector < 0)
3633                         return old_selector;
3634         }
3635
3636         if (ops->set_voltage) {
3637                 ret = _regulator_call_set_voltage(rdev, min_uV, max_uV,
3638                                                   &selector);
3639
3640                 if (ret >= 0) {
3641                         if (ops->list_voltage)
3642                                 best_val = ops->list_voltage(rdev,
3643                                                              selector);
3644                         else
3645                                 best_val = regulator_get_voltage_rdev(rdev);
3646                 }
3647
3648         } else if (ops->set_voltage_sel) {
3649                 ret = regulator_map_voltage(rdev, min_uV, max_uV);
3650                 if (ret >= 0) {
3651                         best_val = ops->list_voltage(rdev, ret);
3652                         if (min_uV <= best_val && max_uV >= best_val) {
3653                                 selector = ret;
3654                                 if (old_selector == selector)
3655                                         ret = 0;
3656                                 else if (rdev->desc->vsel_step)
3657                                         ret = _regulator_set_voltage_sel_step(
3658                                                 rdev, best_val, selector);
3659                                 else
3660                                         ret = _regulator_call_set_voltage_sel(
3661                                                 rdev, best_val, selector);
3662                         } else {
3663                                 ret = -EINVAL;
3664                         }
3665                 }
3666         } else {
3667                 ret = -EINVAL;
3668         }
3669
3670         if (ret)
3671                 goto out;
3672
3673         if (ops->set_voltage_time_sel) {
3674                 /*
3675                  * Call set_voltage_time_sel if successfully obtained
3676                  * old_selector
3677                  */
3678                 if (old_selector >= 0 && old_selector != selector)
3679                         delay = ops->set_voltage_time_sel(rdev, old_selector,
3680                                                           selector);
3681         } else {
3682                 if (old_uV != best_val) {
3683                         if (ops->set_voltage_time)
3684                                 delay = ops->set_voltage_time(rdev, old_uV,
3685                                                               best_val);
3686                         else
3687                                 delay = _regulator_set_voltage_time(rdev,
3688                                                                     old_uV,
3689                                                                     best_val);
3690                 }
3691         }
3692
3693         if (delay < 0) {
3694                 rdev_warn(rdev, "failed to get delay: %pe\n", ERR_PTR(delay));
3695                 delay = 0;
3696         }
3697
3698         /* Insert any necessary delays */
3699         _regulator_delay_helper(delay);
3700
3701         if (best_val >= 0) {
3702                 unsigned long data = best_val;
3703
3704                 _notifier_call_chain(rdev, REGULATOR_EVENT_VOLTAGE_CHANGE,
3705                                      (void *)data);
3706         }
3707
3708 out:
3709         trace_regulator_set_voltage_complete(rdev_get_name(rdev), best_val);
3710
3711         return ret;
3712 }
3713
3714 static int _regulator_do_set_suspend_voltage(struct regulator_dev *rdev,
3715                                   int min_uV, int max_uV, suspend_state_t state)
3716 {
3717         struct regulator_state *rstate;
3718         int uV, sel;
3719
3720         rstate = regulator_get_suspend_state(rdev, state);
3721         if (rstate == NULL)
3722                 return -EINVAL;
3723
3724         if (min_uV < rstate->min_uV)
3725                 min_uV = rstate->min_uV;
3726         if (max_uV > rstate->max_uV)
3727                 max_uV = rstate->max_uV;
3728
3729         sel = regulator_map_voltage(rdev, min_uV, max_uV);
3730         if (sel < 0)
3731                 return sel;
3732
3733         uV = rdev->desc->ops->list_voltage(rdev, sel);
3734         if (uV >= min_uV && uV <= max_uV)
3735                 rstate->uV = uV;
3736
3737         return 0;
3738 }
3739
3740 static int regulator_set_voltage_unlocked(struct regulator *regulator,
3741                                           int min_uV, int max_uV,
3742                                           suspend_state_t state)
3743 {
3744         struct regulator_dev *rdev = regulator->rdev;
3745         struct regulator_voltage *voltage = &regulator->voltage[state];
3746         int ret = 0;
3747         int old_min_uV, old_max_uV;
3748         int current_uV;
3749
3750         /* If we're setting the same range as last time the change
3751          * should be a noop (some cpufreq implementations use the same
3752          * voltage for multiple frequencies, for example).
3753          */
3754         if (voltage->min_uV == min_uV && voltage->max_uV == max_uV)
3755                 goto out;
3756
3757         /* If we're trying to set a range that overlaps the current voltage,
3758          * return successfully even though the regulator does not support
3759          * changing the voltage.
3760          */
3761         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) {
3762                 current_uV = regulator_get_voltage_rdev(rdev);
3763                 if (min_uV <= current_uV && current_uV <= max_uV) {
3764                         voltage->min_uV = min_uV;
3765                         voltage->max_uV = max_uV;
3766                         goto out;
3767                 }
3768         }
3769
3770         /* sanity check */
3771         if (!rdev->desc->ops->set_voltage &&
3772             !rdev->desc->ops->set_voltage_sel) {
3773                 ret = -EINVAL;
3774                 goto out;
3775         }
3776
3777         /* constraints check */
3778         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
3779         if (ret < 0)
3780                 goto out;
3781
3782         /* restore original values in case of error */
3783         old_min_uV = voltage->min_uV;
3784         old_max_uV = voltage->max_uV;
3785         voltage->min_uV = min_uV;
3786         voltage->max_uV = max_uV;
3787
3788         /* for not coupled regulators this will just set the voltage */
3789         ret = regulator_balance_voltage(rdev, state);
3790         if (ret < 0) {
3791                 voltage->min_uV = old_min_uV;
3792                 voltage->max_uV = old_max_uV;
3793         }
3794
3795 out:
3796         return ret;
3797 }
3798
3799 int regulator_set_voltage_rdev(struct regulator_dev *rdev, int min_uV,
3800                                int max_uV, suspend_state_t state)
3801 {
3802         int best_supply_uV = 0;
3803         int supply_change_uV = 0;
3804         int ret;
3805
3806         if (rdev->supply &&
3807             regulator_ops_is_valid(rdev->supply->rdev,
3808                                    REGULATOR_CHANGE_VOLTAGE) &&
3809             (rdev->desc->min_dropout_uV || !(rdev->desc->ops->get_voltage ||
3810                                            rdev->desc->ops->get_voltage_sel))) {
3811                 int current_supply_uV;
3812                 int selector;
3813
3814                 selector = regulator_map_voltage(rdev, min_uV, max_uV);
3815                 if (selector < 0) {
3816                         ret = selector;
3817                         goto out;
3818                 }
3819
3820                 best_supply_uV = _regulator_list_voltage(rdev, selector, 0);
3821                 if (best_supply_uV < 0) {
3822                         ret = best_supply_uV;
3823                         goto out;
3824                 }
3825
3826                 best_supply_uV += rdev->desc->min_dropout_uV;
3827
3828                 current_supply_uV = regulator_get_voltage_rdev(rdev->supply->rdev);
3829                 if (current_supply_uV < 0) {
3830                         ret = current_supply_uV;
3831                         goto out;
3832                 }
3833
3834                 supply_change_uV = best_supply_uV - current_supply_uV;
3835         }
3836
3837         if (supply_change_uV > 0) {
3838                 ret = regulator_set_voltage_unlocked(rdev->supply,
3839                                 best_supply_uV, INT_MAX, state);
3840                 if (ret) {
3841                         dev_err(&rdev->dev, "Failed to increase supply voltage: %pe\n",
3842                                 ERR_PTR(ret));
3843                         goto out;
3844                 }
3845         }
3846
3847         if (state == PM_SUSPEND_ON)
3848                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
3849         else
3850                 ret = _regulator_do_set_suspend_voltage(rdev, min_uV,
3851                                                         max_uV, state);
3852         if (ret < 0)
3853                 goto out;
3854
3855         if (supply_change_uV < 0) {
3856                 ret = regulator_set_voltage_unlocked(rdev->supply,
3857                                 best_supply_uV, INT_MAX, state);
3858                 if (ret)
3859                         dev_warn(&rdev->dev, "Failed to decrease supply voltage: %pe\n",
3860                                  ERR_PTR(ret));
3861                 /* No need to fail here */
3862                 ret = 0;
3863         }
3864
3865 out:
3866         return ret;
3867 }
3868 EXPORT_SYMBOL_GPL(regulator_set_voltage_rdev);
3869
3870 static int regulator_limit_voltage_step(struct regulator_dev *rdev,
3871                                         int *current_uV, int *min_uV)
3872 {
3873         struct regulation_constraints *constraints = rdev->constraints;
3874
3875         /* Limit voltage change only if necessary */
3876         if (!constraints->max_uV_step || !_regulator_is_enabled(rdev))
3877                 return 1;
3878
3879         if (*current_uV < 0) {
3880                 *current_uV = regulator_get_voltage_rdev(rdev);
3881
3882                 if (*current_uV < 0)
3883                         return *current_uV;
3884         }
3885
3886         if (abs(*current_uV - *min_uV) <= constraints->max_uV_step)
3887                 return 1;
3888
3889         /* Clamp target voltage within the given step */
3890         if (*current_uV < *min_uV)
3891                 *min_uV = min(*current_uV + constraints->max_uV_step,
3892                               *min_uV);
3893         else
3894                 *min_uV = max(*current_uV - constraints->max_uV_step,
3895                               *min_uV);
3896
3897         return 0;
3898 }
3899
3900 static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
3901                                          int *current_uV,
3902                                          int *min_uV, int *max_uV,
3903                                          suspend_state_t state,
3904                                          int n_coupled)
3905 {
3906         struct coupling_desc *c_desc = &rdev->coupling_desc;
3907         struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
3908         struct regulation_constraints *constraints = rdev->constraints;
3909         int desired_min_uV = 0, desired_max_uV = INT_MAX;
3910         int max_current_uV = 0, min_current_uV = INT_MAX;
3911         int highest_min_uV = 0, target_uV, possible_uV;
3912         int i, ret, max_spread;
3913         bool done;
3914
3915         *current_uV = -1;
3916
3917         /*
3918          * If there are no coupled regulators, simply set the voltage
3919          * demanded by consumers.
3920          */
3921         if (n_coupled == 1) {
3922                 /*
3923                  * If consumers don't provide any demands, set voltage
3924                  * to min_uV
3925                  */
3926                 desired_min_uV = constraints->min_uV;
3927                 desired_max_uV = constraints->max_uV;
3928
3929                 ret = regulator_check_consumers(rdev,
3930                                                 &desired_min_uV,
3931                                                 &desired_max_uV, state);
3932                 if (ret < 0)
3933                         return ret;
3934
3935                 possible_uV = desired_min_uV;
3936                 done = true;
3937
3938                 goto finish;
3939         }
3940
3941         /* Find highest min desired voltage */
3942         for (i = 0; i < n_coupled; i++) {
3943                 int tmp_min = 0;
3944                 int tmp_max = INT_MAX;
3945
3946                 lockdep_assert_held_once(&c_rdevs[i]->mutex.base);
3947
3948                 ret = regulator_check_consumers(c_rdevs[i],
3949                                                 &tmp_min,
3950                                                 &tmp_max, state);
3951                 if (ret < 0)
3952                         return ret;
3953
3954                 ret = regulator_check_voltage(c_rdevs[i], &tmp_min, &tmp_max);
3955                 if (ret < 0)
3956                         return ret;
3957
3958                 highest_min_uV = max(highest_min_uV, tmp_min);
3959
3960                 if (i == 0) {
3961                         desired_min_uV = tmp_min;
3962                         desired_max_uV = tmp_max;
3963                 }
3964         }
3965
3966         max_spread = constraints->max_spread[0];
3967
3968         /*
3969          * Let target_uV be equal to the desired one if possible.
3970          * If not, set it to minimum voltage, allowed by other coupled
3971          * regulators.
3972          */
3973         target_uV = max(desired_min_uV, highest_min_uV - max_spread);
3974
3975         /*
3976          * Find min and max voltages, which currently aren't violating
3977          * max_spread.
3978          */
3979         for (i = 1; i < n_coupled; i++) {
3980                 int tmp_act;
3981
3982                 if (!_regulator_is_enabled(c_rdevs[i]))
3983                         continue;
3984
3985                 tmp_act = regulator_get_voltage_rdev(c_rdevs[i]);
3986                 if (tmp_act < 0)
3987                         return tmp_act;
3988
3989                 min_current_uV = min(tmp_act, min_current_uV);
3990                 max_current_uV = max(tmp_act, max_current_uV);
3991         }
3992
3993         /* There aren't any other regulators enabled */
3994         if (max_current_uV == 0) {
3995                 possible_uV = target_uV;
3996         } else {
3997                 /*
3998                  * Correct target voltage, so as it currently isn't
3999                  * violating max_spread
4000                  */
4001                 possible_uV = max(target_uV, max_current_uV - max_spread);
4002                 possible_uV = min(possible_uV, min_current_uV + max_spread);
4003         }
4004
4005         if (possible_uV > desired_max_uV)
4006                 return -EINVAL;
4007
4008         done = (possible_uV == target_uV);
4009         desired_min_uV = possible_uV;
4010
4011 finish:
4012         /* Apply max_uV_step constraint if necessary */
4013         if (state == PM_SUSPEND_ON) {
4014                 ret = regulator_limit_voltage_step(rdev, current_uV,
4015                                                    &desired_min_uV);
4016                 if (ret < 0)
4017                         return ret;
4018
4019                 if (ret == 0)
4020                         done = false;
4021         }
4022
4023         /* Set current_uV if wasn't done earlier in the code and if necessary */
4024         if (n_coupled > 1 && *current_uV == -1) {
4025
4026                 if (_regulator_is_enabled(rdev)) {
4027                         ret = regulator_get_voltage_rdev(rdev);
4028                         if (ret < 0)
4029                                 return ret;
4030
4031                         *current_uV = ret;
4032                 } else {
4033                         *current_uV = desired_min_uV;
4034                 }
4035         }
4036
4037         *min_uV = desired_min_uV;
4038         *max_uV = desired_max_uV;
4039
4040         return done;
4041 }
4042
4043 int regulator_do_balance_voltage(struct regulator_dev *rdev,
4044                                  suspend_state_t state, bool skip_coupled)
4045 {
4046         struct regulator_dev **c_rdevs;
4047         struct regulator_dev *best_rdev;
4048         struct coupling_desc *c_desc = &rdev->coupling_desc;
4049         int i, ret, n_coupled, best_min_uV, best_max_uV, best_c_rdev;
4050         unsigned int delta, best_delta;
4051         unsigned long c_rdev_done = 0;
4052         bool best_c_rdev_done;
4053
4054         c_rdevs = c_desc->coupled_rdevs;
4055         n_coupled = skip_coupled ? 1 : c_desc->n_coupled;
4056
4057         /*
4058          * Find the best possible voltage change on each loop. Leave the loop
4059          * if there isn't any possible change.
4060          */
4061         do {
4062                 best_c_rdev_done = false;
4063                 best_delta = 0;
4064                 best_min_uV = 0;
4065                 best_max_uV = 0;
4066                 best_c_rdev = 0;
4067                 best_rdev = NULL;
4068
4069                 /*
4070                  * Find highest difference between optimal voltage
4071                  * and current voltage.
4072                  */
4073                 for (i = 0; i < n_coupled; i++) {
4074                         /*
4075                          * optimal_uV is the best voltage that can be set for
4076                          * i-th regulator at the moment without violating
4077                          * max_spread constraint in order to balance
4078                          * the coupled voltages.
4079                          */
4080                         int optimal_uV = 0, optimal_max_uV = 0, current_uV = 0;
4081
4082                         if (test_bit(i, &c_rdev_done))
4083                                 continue;
4084
4085                         ret = regulator_get_optimal_voltage(c_rdevs[i],
4086                                                             &current_uV,
4087                                                             &optimal_uV,
4088                                                             &optimal_max_uV,
4089                                                             state, n_coupled);
4090                         if (ret < 0)
4091                                 goto out;
4092
4093                         delta = abs(optimal_uV - current_uV);
4094
4095                         if (delta && best_delta <= delta) {
4096                                 best_c_rdev_done = ret;
4097                                 best_delta = delta;
4098                                 best_rdev = c_rdevs[i];
4099                                 best_min_uV = optimal_uV;
4100                                 best_max_uV = optimal_max_uV;
4101                                 best_c_rdev = i;
4102                         }
4103                 }
4104
4105                 /* Nothing to change, return successfully */
4106                 if (!best_rdev) {
4107                         ret = 0;
4108                         goto out;
4109                 }
4110
4111                 ret = regulator_set_voltage_rdev(best_rdev, best_min_uV,
4112                                                  best_max_uV, state);
4113
4114                 if (ret < 0)
4115                         goto out;
4116
4117                 if (best_c_rdev_done)
4118                         set_bit(best_c_rdev, &c_rdev_done);
4119
4120         } while (n_coupled > 1);
4121
4122 out:
4123         return ret;
4124 }
4125
4126 static int regulator_balance_voltage(struct regulator_dev *rdev,
4127                                      suspend_state_t state)
4128 {
4129         struct coupling_desc *c_desc = &rdev->coupling_desc;
4130         struct regulator_coupler *coupler = c_desc->coupler;
4131         bool skip_coupled = false;
4132
4133         /*
4134          * If system is in a state other than PM_SUSPEND_ON, don't check
4135          * other coupled regulators.
4136          */
4137         if (state != PM_SUSPEND_ON)
4138                 skip_coupled = true;
4139
4140         if (c_desc->n_resolved < c_desc->n_coupled) {
4141                 rdev_err(rdev, "Not all coupled regulators registered\n");
4142                 return -EPERM;
4143         }
4144
4145         /* Invoke custom balancer for customized couplers */
4146         if (coupler && coupler->balance_voltage)
4147                 return coupler->balance_voltage(coupler, rdev, state);
4148
4149         return regulator_do_balance_voltage(rdev, state, skip_coupled);
4150 }
4151
4152 /**
4153  * regulator_set_voltage - set regulator output voltage
4154  * @regulator: regulator source
4155  * @min_uV: Minimum required voltage in uV
4156  * @max_uV: Maximum acceptable voltage in uV
4157  *
4158  * Sets a voltage regulator to the desired output voltage. This can be set
4159  * during any regulator state. IOW, regulator can be disabled or enabled.
4160  *
4161  * If the regulator is enabled then the voltage will change to the new value
4162  * immediately otherwise if the regulator is disabled the regulator will
4163  * output at the new voltage when enabled.
4164  *
4165  * NOTE: If the regulator is shared between several devices then the lowest
4166  * request voltage that meets the system constraints will be used.
4167  * Regulator system constraints must be set for this regulator before
4168  * calling this function otherwise this call will fail.
4169  */
4170 int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV)
4171 {
4172         struct ww_acquire_ctx ww_ctx;
4173         int ret;
4174
4175         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4176
4177         ret = regulator_set_voltage_unlocked(regulator, min_uV, max_uV,
4178                                              PM_SUSPEND_ON);
4179
4180         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4181
4182         return ret;
4183 }
4184 EXPORT_SYMBOL_GPL(regulator_set_voltage);
4185
4186 static inline int regulator_suspend_toggle(struct regulator_dev *rdev,
4187                                            suspend_state_t state, bool en)
4188 {
4189         struct regulator_state *rstate;
4190
4191         rstate = regulator_get_suspend_state(rdev, state);
4192         if (rstate == NULL)
4193                 return -EINVAL;
4194
4195         if (!rstate->changeable)
4196                 return -EPERM;
4197
4198         rstate->enabled = (en) ? ENABLE_IN_SUSPEND : DISABLE_IN_SUSPEND;
4199
4200         return 0;
4201 }
4202
4203 int regulator_suspend_enable(struct regulator_dev *rdev,
4204                                     suspend_state_t state)
4205 {
4206         return regulator_suspend_toggle(rdev, state, true);
4207 }
4208 EXPORT_SYMBOL_GPL(regulator_suspend_enable);
4209
4210 int regulator_suspend_disable(struct regulator_dev *rdev,
4211                                      suspend_state_t state)
4212 {
4213         struct regulator *regulator;
4214         struct regulator_voltage *voltage;
4215
4216         /*
4217          * if any consumer wants this regulator device keeping on in
4218          * suspend states, don't set it as disabled.
4219          */
4220         list_for_each_entry(regulator, &rdev->consumer_list, list) {
4221                 voltage = &regulator->voltage[state];
4222                 if (voltage->min_uV || voltage->max_uV)
4223                         return 0;
4224         }
4225
4226         return regulator_suspend_toggle(rdev, state, false);
4227 }
4228 EXPORT_SYMBOL_GPL(regulator_suspend_disable);
4229
4230 static int _regulator_set_suspend_voltage(struct regulator *regulator,
4231                                           int min_uV, int max_uV,
4232                                           suspend_state_t state)
4233 {
4234         struct regulator_dev *rdev = regulator->rdev;
4235         struct regulator_state *rstate;
4236
4237         rstate = regulator_get_suspend_state(rdev, state);
4238         if (rstate == NULL)
4239                 return -EINVAL;
4240
4241         if (rstate->min_uV == rstate->max_uV) {
4242                 rdev_err(rdev, "The suspend voltage can't be changed!\n");
4243                 return -EPERM;
4244         }
4245
4246         return regulator_set_voltage_unlocked(regulator, min_uV, max_uV, state);
4247 }
4248
4249 int regulator_set_suspend_voltage(struct regulator *regulator, int min_uV,
4250                                   int max_uV, suspend_state_t state)
4251 {
4252         struct ww_acquire_ctx ww_ctx;
4253         int ret;
4254
4255         /* PM_SUSPEND_ON is handled by regulator_set_voltage() */
4256         if (regulator_check_states(state) || state == PM_SUSPEND_ON)
4257                 return -EINVAL;
4258
4259         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4260
4261         ret = _regulator_set_suspend_voltage(regulator, min_uV,
4262                                              max_uV, state);
4263
4264         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4265
4266         return ret;
4267 }
4268 EXPORT_SYMBOL_GPL(regulator_set_suspend_voltage);
4269
4270 /**
4271  * regulator_set_voltage_time - get raise/fall time
4272  * @regulator: regulator source
4273  * @old_uV: starting voltage in microvolts
4274  * @new_uV: target voltage in microvolts
4275  *
4276  * Provided with the starting and ending voltage, this function attempts to
4277  * calculate the time in microseconds required to rise or fall to this new
4278  * voltage.
4279  */
4280 int regulator_set_voltage_time(struct regulator *regulator,
4281                                int old_uV, int new_uV)
4282 {
4283         struct regulator_dev *rdev = regulator->rdev;
4284         const struct regulator_ops *ops = rdev->desc->ops;
4285         int old_sel = -1;
4286         int new_sel = -1;
4287         int voltage;
4288         int i;
4289
4290         if (ops->set_voltage_time)
4291                 return ops->set_voltage_time(rdev, old_uV, new_uV);
4292         else if (!ops->set_voltage_time_sel)
4293                 return _regulator_set_voltage_time(rdev, old_uV, new_uV);
4294
4295         /* Currently requires operations to do this */
4296         if (!ops->list_voltage || !rdev->desc->n_voltages)
4297                 return -EINVAL;
4298
4299         for (i = 0; i < rdev->desc->n_voltages; i++) {
4300                 /* We only look for exact voltage matches here */
4301                 if (i < rdev->desc->linear_min_sel)
4302                         continue;
4303
4304                 if (old_sel >= 0 && new_sel >= 0)
4305                         break;
4306
4307                 voltage = regulator_list_voltage(regulator, i);
4308                 if (voltage < 0)
4309                         return -EINVAL;
4310                 if (voltage == 0)
4311                         continue;
4312                 if (voltage == old_uV)
4313                         old_sel = i;
4314                 if (voltage == new_uV)
4315                         new_sel = i;
4316         }
4317
4318         if (old_sel < 0 || new_sel < 0)
4319                 return -EINVAL;
4320
4321         return ops->set_voltage_time_sel(rdev, old_sel, new_sel);
4322 }
4323 EXPORT_SYMBOL_GPL(regulator_set_voltage_time);
4324
4325 /**
4326  * regulator_set_voltage_time_sel - get raise/fall time
4327  * @rdev: regulator source device
4328  * @old_selector: selector for starting voltage
4329  * @new_selector: selector for target voltage
4330  *
4331  * Provided with the starting and target voltage selectors, this function
4332  * returns time in microseconds required to rise or fall to this new voltage
4333  *
4334  * Drivers providing ramp_delay in regulation_constraints can use this as their
4335  * set_voltage_time_sel() operation.
4336  */
4337 int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
4338                                    unsigned int old_selector,
4339                                    unsigned int new_selector)
4340 {
4341         int old_volt, new_volt;
4342
4343         /* sanity check */
4344         if (!rdev->desc->ops->list_voltage)
4345                 return -EINVAL;
4346
4347         old_volt = rdev->desc->ops->list_voltage(rdev, old_selector);
4348         new_volt = rdev->desc->ops->list_voltage(rdev, new_selector);
4349
4350         if (rdev->desc->ops->set_voltage_time)
4351                 return rdev->desc->ops->set_voltage_time(rdev, old_volt,
4352                                                          new_volt);
4353         else
4354                 return _regulator_set_voltage_time(rdev, old_volt, new_volt);
4355 }
4356 EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);
4357
4358 int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
4359 {
4360         int ret;
4361
4362         regulator_lock(rdev);
4363
4364         if (!rdev->desc->ops->set_voltage &&
4365             !rdev->desc->ops->set_voltage_sel) {
4366                 ret = -EINVAL;
4367                 goto out;
4368         }
4369
4370         /* balance only, if regulator is coupled */
4371         if (rdev->coupling_desc.n_coupled > 1)
4372                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4373         else
4374                 ret = -EOPNOTSUPP;
4375
4376 out:
4377         regulator_unlock(rdev);
4378         return ret;
4379 }
4380
4381 /**
4382  * regulator_sync_voltage - re-apply last regulator output voltage
4383  * @regulator: regulator source
4384  *
4385  * Re-apply the last configured voltage.  This is intended to be used
4386  * where some external control source the consumer is cooperating with
4387  * has caused the configured voltage to change.
4388  */
4389 int regulator_sync_voltage(struct regulator *regulator)
4390 {
4391         struct regulator_dev *rdev = regulator->rdev;
4392         struct regulator_voltage *voltage = &regulator->voltage[PM_SUSPEND_ON];
4393         int ret, min_uV, max_uV;
4394
4395         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE))
4396                 return 0;
4397
4398         regulator_lock(rdev);
4399
4400         if (!rdev->desc->ops->set_voltage &&
4401             !rdev->desc->ops->set_voltage_sel) {
4402                 ret = -EINVAL;
4403                 goto out;
4404         }
4405
4406         /* This is only going to work if we've had a voltage configured. */
4407         if (!voltage->min_uV && !voltage->max_uV) {
4408                 ret = -EINVAL;
4409                 goto out;
4410         }
4411
4412         min_uV = voltage->min_uV;
4413         max_uV = voltage->max_uV;
4414
4415         /* This should be a paranoia check... */
4416         ret = regulator_check_voltage(rdev, &min_uV, &max_uV);
4417         if (ret < 0)
4418                 goto out;
4419
4420         ret = regulator_check_consumers(rdev, &min_uV, &max_uV, 0);
4421         if (ret < 0)
4422                 goto out;
4423
4424         /* balance only, if regulator is coupled */
4425         if (rdev->coupling_desc.n_coupled > 1)
4426                 ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
4427         else
4428                 ret = _regulator_do_set_voltage(rdev, min_uV, max_uV);
4429
4430 out:
4431         regulator_unlock(rdev);
4432         return ret;
4433 }
4434 EXPORT_SYMBOL_GPL(regulator_sync_voltage);
4435
4436 int regulator_get_voltage_rdev(struct regulator_dev *rdev)
4437 {
4438         int sel, ret;
4439         bool bypassed;
4440
4441         if (rdev->desc->ops->get_bypass) {
4442                 ret = rdev->desc->ops->get_bypass(rdev, &bypassed);
4443                 if (ret < 0)
4444                         return ret;
4445                 if (bypassed) {
4446                         /* if bypassed the regulator must have a supply */
4447                         if (!rdev->supply) {
4448                                 rdev_err(rdev,
4449                                          "bypassed regulator has no supply!\n");
4450                                 return -EPROBE_DEFER;
4451                         }
4452
4453                         return regulator_get_voltage_rdev(rdev->supply->rdev);
4454                 }
4455         }
4456
4457         if (rdev->desc->ops->get_voltage_sel) {
4458                 sel = rdev->desc->ops->get_voltage_sel(rdev);
4459                 if (sel < 0)
4460                         return sel;
4461                 ret = rdev->desc->ops->list_voltage(rdev, sel);
4462         } else if (rdev->desc->ops->get_voltage) {
4463                 ret = rdev->desc->ops->get_voltage(rdev);
4464         } else if (rdev->desc->ops->list_voltage) {
4465                 ret = rdev->desc->ops->list_voltage(rdev, 0);
4466         } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages == 1)) {
4467                 ret = rdev->desc->fixed_uV;
4468         } else if (rdev->supply) {
4469                 ret = regulator_get_voltage_rdev(rdev->supply->rdev);
4470         } else if (rdev->supply_name) {
4471                 return -EPROBE_DEFER;
4472         } else {
4473                 return -EINVAL;
4474         }
4475
4476         if (ret < 0)
4477                 return ret;
4478         return ret - rdev->constraints->uV_offset;
4479 }
4480 EXPORT_SYMBOL_GPL(regulator_get_voltage_rdev);
4481
4482 /**
4483  * regulator_get_voltage - get regulator output voltage
4484  * @regulator: regulator source
4485  *
4486  * This returns the current regulator voltage in uV.
4487  *
4488  * NOTE: If the regulator is disabled it will return the voltage value. This
4489  * function should not be used to determine regulator state.
4490  */
4491 int regulator_get_voltage(struct regulator *regulator)
4492 {
4493         struct ww_acquire_ctx ww_ctx;
4494         int ret;
4495
4496         regulator_lock_dependent(regulator->rdev, &ww_ctx);
4497         ret = regulator_get_voltage_rdev(regulator->rdev);
4498         regulator_unlock_dependent(regulator->rdev, &ww_ctx);
4499
4500         return ret;
4501 }
4502 EXPORT_SYMBOL_GPL(regulator_get_voltage);
4503
4504 /**
4505  * regulator_set_current_limit - set regulator output current limit
4506  * @regulator: regulator source
4507  * @min_uA: Minimum supported current in uA
4508  * @max_uA: Maximum supported current in uA
4509  *
4510  * Sets current sink to the desired output current. This can be set during
4511  * any regulator state. IOW, regulator can be disabled or enabled.
4512  *
4513  * If the regulator is enabled then the current will change to the new value
4514  * immediately otherwise if the regulator is disabled the regulator will
4515  * output at the new current when enabled.
4516  *
4517  * NOTE: Regulator system constraints must be set for this regulator before
4518  * calling this function otherwise this call will fail.
4519  */
4520 int regulator_set_current_limit(struct regulator *regulator,
4521                                int min_uA, int max_uA)
4522 {
4523         struct regulator_dev *rdev = regulator->rdev;
4524         int ret;
4525
4526         regulator_lock(rdev);
4527
4528         /* sanity check */
4529         if (!rdev->desc->ops->set_current_limit) {
4530                 ret = -EINVAL;
4531                 goto out;
4532         }
4533
4534         /* constraints check */
4535         ret = regulator_check_current_limit(rdev, &min_uA, &max_uA);
4536         if (ret < 0)
4537                 goto out;
4538
4539         ret = rdev->desc->ops->set_current_limit(rdev, min_uA, max_uA);
4540 out:
4541         regulator_unlock(rdev);
4542         return ret;
4543 }
4544 EXPORT_SYMBOL_GPL(regulator_set_current_limit);
4545
4546 static int _regulator_get_current_limit_unlocked(struct regulator_dev *rdev)
4547 {
4548         /* sanity check */
4549         if (!rdev->desc->ops->get_current_limit)
4550                 return -EINVAL;
4551
4552         return rdev->desc->ops->get_current_limit(rdev);
4553 }
4554
4555 static int _regulator_get_current_limit(struct regulator_dev *rdev)
4556 {
4557         int ret;
4558
4559         regulator_lock(rdev);
4560         ret = _regulator_get_current_limit_unlocked(rdev);
4561         regulator_unlock(rdev);
4562
4563         return ret;
4564 }
4565
4566 /**
4567  * regulator_get_current_limit - get regulator output current
4568  * @regulator: regulator source
4569  *
4570  * This returns the current supplied by the specified current sink in uA.
4571  *
4572  * NOTE: If the regulator is disabled it will return the current value. This
4573  * function should not be used to determine regulator state.
4574  */
4575 int regulator_get_current_limit(struct regulator *regulator)
4576 {
4577         return _regulator_get_current_limit(regulator->rdev);
4578 }
4579 EXPORT_SYMBOL_GPL(regulator_get_current_limit);
4580
4581 /**
4582  * regulator_set_mode - set regulator operating mode
4583  * @regulator: regulator source
4584  * @mode: operating mode - one of the REGULATOR_MODE constants
4585  *
4586  * Set regulator operating mode to increase regulator efficiency or improve
4587  * regulation performance.
4588  *
4589  * NOTE: Regulator system constraints must be set for this regulator before
4590  * calling this function otherwise this call will fail.
4591  */
4592 int regulator_set_mode(struct regulator *regulator, unsigned int mode)
4593 {
4594         struct regulator_dev *rdev = regulator->rdev;
4595         int ret;
4596         int regulator_curr_mode;
4597
4598         regulator_lock(rdev);
4599
4600         /* sanity check */
4601         if (!rdev->desc->ops->set_mode) {
4602                 ret = -EINVAL;
4603                 goto out;
4604         }
4605
4606         /* return if the same mode is requested */
4607         if (rdev->desc->ops->get_mode) {
4608                 regulator_curr_mode = rdev->desc->ops->get_mode(rdev);
4609                 if (regulator_curr_mode == mode) {
4610                         ret = 0;
4611                         goto out;
4612                 }
4613         }
4614
4615         /* constraints check */
4616         ret = regulator_mode_constrain(rdev, &mode);
4617         if (ret < 0)
4618                 goto out;
4619
4620         ret = rdev->desc->ops->set_mode(rdev, mode);
4621 out:
4622         regulator_unlock(rdev);
4623         return ret;
4624 }
4625 EXPORT_SYMBOL_GPL(regulator_set_mode);
4626
4627 static unsigned int _regulator_get_mode_unlocked(struct regulator_dev *rdev)
4628 {
4629         /* sanity check */
4630         if (!rdev->desc->ops->get_mode)
4631                 return -EINVAL;
4632
4633         return rdev->desc->ops->get_mode(rdev);
4634 }
4635
4636 static unsigned int _regulator_get_mode(struct regulator_dev *rdev)
4637 {
4638         int ret;
4639
4640         regulator_lock(rdev);
4641         ret = _regulator_get_mode_unlocked(rdev);
4642         regulator_unlock(rdev);
4643
4644         return ret;
4645 }
4646
4647 /**
4648  * regulator_get_mode - get regulator operating mode
4649  * @regulator: regulator source
4650  *
4651  * Get the current regulator operating mode.
4652  */
4653 unsigned int regulator_get_mode(struct regulator *regulator)
4654 {
4655         return _regulator_get_mode(regulator->rdev);
4656 }
4657 EXPORT_SYMBOL_GPL(regulator_get_mode);
4658
4659 static int rdev_get_cached_err_flags(struct regulator_dev *rdev)
4660 {
4661         int ret = 0;
4662
4663         if (rdev->use_cached_err) {
4664                 spin_lock(&rdev->err_lock);
4665                 ret = rdev->cached_err;
4666                 spin_unlock(&rdev->err_lock);
4667         }
4668         return ret;
4669 }
4670
4671 static int _regulator_get_error_flags(struct regulator_dev *rdev,
4672                                         unsigned int *flags)
4673 {
4674         int cached_flags, ret = 0;
4675
4676         regulator_lock(rdev);
4677
4678         cached_flags = rdev_get_cached_err_flags(rdev);
4679
4680         if (rdev->desc->ops->get_error_flags)
4681                 ret = rdev->desc->ops->get_error_flags(rdev, flags);
4682         else if (!rdev->use_cached_err)
4683                 ret = -EINVAL;
4684
4685         *flags |= cached_flags;
4686
4687         regulator_unlock(rdev);
4688
4689         return ret;
4690 }
4691
4692 /**
4693  * regulator_get_error_flags - get regulator error information
4694  * @regulator: regulator source
4695  * @flags: pointer to store error flags
4696  *
4697  * Get the current regulator error information.
4698  */
4699 int regulator_get_error_flags(struct regulator *regulator,
4700                                 unsigned int *flags)
4701 {
4702         return _regulator_get_error_flags(regulator->rdev, flags);
4703 }
4704 EXPORT_SYMBOL_GPL(regulator_get_error_flags);
4705
4706 /**
4707  * regulator_set_load - set regulator load
4708  * @regulator: regulator source
4709  * @uA_load: load current
4710  *
4711  * Notifies the regulator core of a new device load. This is then used by
4712  * DRMS (if enabled by constraints) to set the most efficient regulator
4713  * operating mode for the new regulator loading.
4714  *
4715  * Consumer devices notify their supply regulator of the maximum power
4716  * they will require (can be taken from device datasheet in the power
4717  * consumption tables) when they change operational status and hence power
4718  * state. Examples of operational state changes that can affect power
4719  * consumption are :-
4720  *
4721  *    o Device is opened / closed.
4722  *    o Device I/O is about to begin or has just finished.
4723  *    o Device is idling in between work.
4724  *
4725  * This information is also exported via sysfs to userspace.
4726  *
4727  * DRMS will sum the total requested load on the regulator and change
4728  * to the most efficient operating mode if platform constraints allow.
4729  *
4730  * NOTE: when a regulator consumer requests to have a regulator
4731  * disabled then any load that consumer requested no longer counts
4732  * toward the total requested load.  If the regulator is re-enabled
4733  * then the previously requested load will start counting again.
4734  *
4735  * If a regulator is an always-on regulator then an individual consumer's
4736  * load will still be removed if that consumer is fully disabled.
4737  *
4738  * On error a negative errno is returned.
4739  */
4740 int regulator_set_load(struct regulator *regulator, int uA_load)
4741 {
4742         struct regulator_dev *rdev = regulator->rdev;
4743         int old_uA_load;
4744         int ret = 0;
4745
4746         regulator_lock(rdev);
4747         old_uA_load = regulator->uA_load;
4748         regulator->uA_load = uA_load;
4749         if (regulator->enable_count && old_uA_load != uA_load) {
4750                 ret = drms_uA_update(rdev);
4751                 if (ret < 0)
4752                         regulator->uA_load = old_uA_load;
4753         }
4754         regulator_unlock(rdev);
4755
4756         return ret;
4757 }
4758 EXPORT_SYMBOL_GPL(regulator_set_load);
4759
4760 /**
4761  * regulator_allow_bypass - allow the regulator to go into bypass mode
4762  *
4763  * @regulator: Regulator to configure
4764  * @enable: enable or disable bypass mode
4765  *
4766  * Allow the regulator to go into bypass mode if all other consumers
4767  * for the regulator also enable bypass mode and the machine
4768  * constraints allow this.  Bypass mode means that the regulator is
4769  * simply passing the input directly to the output with no regulation.
4770  */
4771 int regulator_allow_bypass(struct regulator *regulator, bool enable)
4772 {
4773         struct regulator_dev *rdev = regulator->rdev;
4774         const char *name = rdev_get_name(rdev);
4775         int ret = 0;
4776
4777         if (!rdev->desc->ops->set_bypass)
4778                 return 0;
4779
4780         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_BYPASS))
4781                 return 0;
4782
4783         regulator_lock(rdev);
4784
4785         if (enable && !regulator->bypass) {
4786                 rdev->bypass_count++;
4787
4788                 if (rdev->bypass_count == rdev->open_count) {
4789                         trace_regulator_bypass_enable(name);
4790
4791                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4792                         if (ret != 0)
4793                                 rdev->bypass_count--;
4794                         else
4795                                 trace_regulator_bypass_enable_complete(name);
4796                 }
4797
4798         } else if (!enable && regulator->bypass) {
4799                 rdev->bypass_count--;
4800
4801                 if (rdev->bypass_count != rdev->open_count) {
4802                         trace_regulator_bypass_disable(name);
4803
4804                         ret = rdev->desc->ops->set_bypass(rdev, enable);
4805                         if (ret != 0)
4806                                 rdev->bypass_count++;
4807                         else
4808                                 trace_regulator_bypass_disable_complete(name);
4809                 }
4810         }
4811
4812         if (ret == 0)
4813                 regulator->bypass = enable;
4814
4815         regulator_unlock(rdev);
4816
4817         return ret;
4818 }
4819 EXPORT_SYMBOL_GPL(regulator_allow_bypass);
4820
4821 /**
4822  * regulator_register_notifier - register regulator event notifier
4823  * @regulator: regulator source
4824  * @nb: notifier block
4825  *
4826  * Register notifier block to receive regulator events.
4827  */
4828 int regulator_register_notifier(struct regulator *regulator,
4829                               struct notifier_block *nb)
4830 {
4831         return blocking_notifier_chain_register(&regulator->rdev->notifier,
4832                                                 nb);
4833 }
4834 EXPORT_SYMBOL_GPL(regulator_register_notifier);
4835
4836 /**
4837  * regulator_unregister_notifier - unregister regulator event notifier
4838  * @regulator: regulator source
4839  * @nb: notifier block
4840  *
4841  * Unregister regulator event notifier block.
4842  */
4843 int regulator_unregister_notifier(struct regulator *regulator,
4844                                 struct notifier_block *nb)
4845 {
4846         return blocking_notifier_chain_unregister(&regulator->rdev->notifier,
4847                                                   nb);
4848 }
4849 EXPORT_SYMBOL_GPL(regulator_unregister_notifier);
4850
4851 /* notify regulator consumers and downstream regulator consumers.
4852  * Note mutex must be held by caller.
4853  */
4854 static int _notifier_call_chain(struct regulator_dev *rdev,
4855                                   unsigned long event, void *data)
4856 {
4857         /* call rdev chain first */
4858         int ret =  blocking_notifier_call_chain(&rdev->notifier, event, data);
4859
4860         if (IS_REACHABLE(CONFIG_REGULATOR_NETLINK_EVENTS)) {
4861                 struct device *parent = rdev->dev.parent;
4862                 const char *rname = rdev_get_name(rdev);
4863                 char name[32];
4864
4865                 /* Avoid duplicate debugfs directory names */
4866                 if (parent && rname == rdev->desc->name) {
4867                         snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
4868                                  rname);
4869                         rname = name;
4870                 }
4871                 reg_generate_netlink_event(rname, event);
4872         }
4873
4874         return ret;
4875 }
4876
4877 int _regulator_bulk_get(struct device *dev, int num_consumers,
4878                         struct regulator_bulk_data *consumers, enum regulator_get_type get_type)
4879 {
4880         int i;
4881         int ret;
4882
4883         for (i = 0; i < num_consumers; i++)
4884                 consumers[i].consumer = NULL;
4885
4886         for (i = 0; i < num_consumers; i++) {
4887                 consumers[i].consumer = _regulator_get(dev,
4888                                                        consumers[i].supply, get_type);
4889                 if (IS_ERR(consumers[i].consumer)) {
4890                         ret = dev_err_probe(dev, PTR_ERR(consumers[i].consumer),
4891                                             "Failed to get supply '%s'",
4892                                             consumers[i].supply);
4893                         consumers[i].consumer = NULL;
4894                         goto err;
4895                 }
4896
4897                 if (consumers[i].init_load_uA > 0) {
4898                         ret = regulator_set_load(consumers[i].consumer,
4899                                                  consumers[i].init_load_uA);
4900                         if (ret) {
4901                                 i++;
4902                                 goto err;
4903                         }
4904                 }
4905         }
4906
4907         return 0;
4908
4909 err:
4910         while (--i >= 0)
4911                 regulator_put(consumers[i].consumer);
4912
4913         return ret;
4914 }
4915
4916 /**
4917  * regulator_bulk_get - get multiple regulator consumers
4918  *
4919  * @dev:           Device to supply
4920  * @num_consumers: Number of consumers to register
4921  * @consumers:     Configuration of consumers; clients are stored here.
4922  *
4923  * @return 0 on success, an errno on failure.
4924  *
4925  * This helper function allows drivers to get several regulator
4926  * consumers in one operation.  If any of the regulators cannot be
4927  * acquired then any regulators that were allocated will be freed
4928  * before returning to the caller.
4929  */
4930 int regulator_bulk_get(struct device *dev, int num_consumers,
4931                        struct regulator_bulk_data *consumers)
4932 {
4933         return _regulator_bulk_get(dev, num_consumers, consumers, NORMAL_GET);
4934 }
4935 EXPORT_SYMBOL_GPL(regulator_bulk_get);
4936
4937 static void regulator_bulk_enable_async(void *data, async_cookie_t cookie)
4938 {
4939         struct regulator_bulk_data *bulk = data;
4940
4941         bulk->ret = regulator_enable(bulk->consumer);
4942 }
4943
4944 /**
4945  * regulator_bulk_enable - enable multiple regulator consumers
4946  *
4947  * @num_consumers: Number of consumers
4948  * @consumers:     Consumer data; clients are stored here.
4949  * @return         0 on success, an errno on failure
4950  *
4951  * This convenience API allows consumers to enable multiple regulator
4952  * clients in a single API call.  If any consumers cannot be enabled
4953  * then any others that were enabled will be disabled again prior to
4954  * return.
4955  */
4956 int regulator_bulk_enable(int num_consumers,
4957                           struct regulator_bulk_data *consumers)
4958 {
4959         ASYNC_DOMAIN_EXCLUSIVE(async_domain);
4960         int i;
4961         int ret = 0;
4962
4963         for (i = 0; i < num_consumers; i++) {
4964                 async_schedule_domain(regulator_bulk_enable_async,
4965                                       &consumers[i], &async_domain);
4966         }
4967
4968         async_synchronize_full_domain(&async_domain);
4969
4970         /* If any consumer failed we need to unwind any that succeeded */
4971         for (i = 0; i < num_consumers; i++) {
4972                 if (consumers[i].ret != 0) {
4973                         ret = consumers[i].ret;
4974                         goto err;
4975                 }
4976         }
4977
4978         return 0;
4979
4980 err:
4981         for (i = 0; i < num_consumers; i++) {
4982                 if (consumers[i].ret < 0)
4983                         pr_err("Failed to enable %s: %pe\n", consumers[i].supply,
4984                                ERR_PTR(consumers[i].ret));
4985                 else
4986                         regulator_disable(consumers[i].consumer);
4987         }
4988
4989         return ret;
4990 }
4991 EXPORT_SYMBOL_GPL(regulator_bulk_enable);
4992
4993 /**
4994  * regulator_bulk_disable - disable multiple regulator consumers
4995  *
4996  * @num_consumers: Number of consumers
4997  * @consumers:     Consumer data; clients are stored here.
4998  * @return         0 on success, an errno on failure
4999  *
5000  * This convenience API allows consumers to disable multiple regulator
5001  * clients in a single API call.  If any consumers cannot be disabled
5002  * then any others that were disabled will be enabled again prior to
5003  * return.
5004  */
5005 int regulator_bulk_disable(int num_consumers,
5006                            struct regulator_bulk_data *consumers)
5007 {
5008         int i;
5009         int ret, r;
5010
5011         for (i = num_consumers - 1; i >= 0; --i) {
5012                 ret = regulator_disable(consumers[i].consumer);
5013                 if (ret != 0)
5014                         goto err;
5015         }
5016
5017         return 0;
5018
5019 err:
5020         pr_err("Failed to disable %s: %pe\n", consumers[i].supply, ERR_PTR(ret));
5021         for (++i; i < num_consumers; ++i) {
5022                 r = regulator_enable(consumers[i].consumer);
5023                 if (r != 0)
5024                         pr_err("Failed to re-enable %s: %pe\n",
5025                                consumers[i].supply, ERR_PTR(r));
5026         }
5027
5028         return ret;
5029 }
5030 EXPORT_SYMBOL_GPL(regulator_bulk_disable);
5031
5032 /**
5033  * regulator_bulk_force_disable - force disable multiple regulator consumers
5034  *
5035  * @num_consumers: Number of consumers
5036  * @consumers:     Consumer data; clients are stored here.
5037  * @return         0 on success, an errno on failure
5038  *
5039  * This convenience API allows consumers to forcibly disable multiple regulator
5040  * clients in a single API call.
5041  * NOTE: This should be used for situations when device damage will
5042  * likely occur if the regulators are not disabled (e.g. over temp).
5043  * Although regulator_force_disable function call for some consumers can
5044  * return error numbers, the function is called for all consumers.
5045  */
5046 int regulator_bulk_force_disable(int num_consumers,
5047                            struct regulator_bulk_data *consumers)
5048 {
5049         int i;
5050         int ret = 0;
5051
5052         for (i = 0; i < num_consumers; i++) {
5053                 consumers[i].ret =
5054                             regulator_force_disable(consumers[i].consumer);
5055
5056                 /* Store first error for reporting */
5057                 if (consumers[i].ret && !ret)
5058                         ret = consumers[i].ret;
5059         }
5060
5061         return ret;
5062 }
5063 EXPORT_SYMBOL_GPL(regulator_bulk_force_disable);
5064
5065 /**
5066  * regulator_bulk_free - free multiple regulator consumers
5067  *
5068  * @num_consumers: Number of consumers
5069  * @consumers:     Consumer data; clients are stored here.
5070  *
5071  * This convenience API allows consumers to free multiple regulator
5072  * clients in a single API call.
5073  */
5074 void regulator_bulk_free(int num_consumers,
5075                          struct regulator_bulk_data *consumers)
5076 {
5077         int i;
5078
5079         for (i = 0; i < num_consumers; i++) {
5080                 regulator_put(consumers[i].consumer);
5081                 consumers[i].consumer = NULL;
5082         }
5083 }
5084 EXPORT_SYMBOL_GPL(regulator_bulk_free);
5085
5086 /**
5087  * regulator_handle_critical - Handle events for system-critical regulators.
5088  * @rdev: The regulator device.
5089  * @event: The event being handled.
5090  *
5091  * This function handles critical events such as under-voltage, over-current,
5092  * and unknown errors for regulators deemed system-critical. On detecting such
5093  * events, it triggers a hardware protection shutdown with a defined timeout.
5094  */
5095 static void regulator_handle_critical(struct regulator_dev *rdev,
5096                                       unsigned long event)
5097 {
5098         const char *reason = NULL;
5099
5100         if (!rdev->constraints->system_critical)
5101                 return;
5102
5103         switch (event) {
5104         case REGULATOR_EVENT_UNDER_VOLTAGE:
5105                 reason = "System critical regulator: voltage drop detected";
5106                 break;
5107         case REGULATOR_EVENT_OVER_CURRENT:
5108                 reason = "System critical regulator: over-current detected";
5109                 break;
5110         case REGULATOR_EVENT_FAIL:
5111                 reason = "System critical regulator: unknown error";
5112         }
5113
5114         if (!reason)
5115                 return;
5116
5117         hw_protection_shutdown(reason,
5118                                rdev->constraints->uv_less_critical_window_ms);
5119 }
5120
5121 /**
5122  * regulator_notifier_call_chain - call regulator event notifier
5123  * @rdev: regulator source
5124  * @event: notifier block
5125  * @data: callback-specific data.
5126  *
5127  * Called by regulator drivers to notify clients a regulator event has
5128  * occurred.
5129  */
5130 int regulator_notifier_call_chain(struct regulator_dev *rdev,
5131                                   unsigned long event, void *data)
5132 {
5133         regulator_handle_critical(rdev, event);
5134
5135         _notifier_call_chain(rdev, event, data);
5136         return NOTIFY_DONE;
5137
5138 }
5139 EXPORT_SYMBOL_GPL(regulator_notifier_call_chain);
5140
5141 /**
5142  * regulator_mode_to_status - convert a regulator mode into a status
5143  *
5144  * @mode: Mode to convert
5145  *
5146  * Convert a regulator mode into a status.
5147  */
5148 int regulator_mode_to_status(unsigned int mode)
5149 {
5150         switch (mode) {
5151         case REGULATOR_MODE_FAST:
5152                 return REGULATOR_STATUS_FAST;
5153         case REGULATOR_MODE_NORMAL:
5154                 return REGULATOR_STATUS_NORMAL;
5155         case REGULATOR_MODE_IDLE:
5156                 return REGULATOR_STATUS_IDLE;
5157         case REGULATOR_MODE_STANDBY:
5158                 return REGULATOR_STATUS_STANDBY;
5159         default:
5160                 return REGULATOR_STATUS_UNDEFINED;
5161         }
5162 }
5163 EXPORT_SYMBOL_GPL(regulator_mode_to_status);
5164
5165 static struct attribute *regulator_dev_attrs[] = {
5166         &dev_attr_name.attr,
5167         &dev_attr_num_users.attr,
5168         &dev_attr_type.attr,
5169         &dev_attr_microvolts.attr,
5170         &dev_attr_microamps.attr,
5171         &dev_attr_opmode.attr,
5172         &dev_attr_state.attr,
5173         &dev_attr_status.attr,
5174         &dev_attr_bypass.attr,
5175         &dev_attr_requested_microamps.attr,
5176         &dev_attr_min_microvolts.attr,
5177         &dev_attr_max_microvolts.attr,
5178         &dev_attr_min_microamps.attr,
5179         &dev_attr_max_microamps.attr,
5180         &dev_attr_under_voltage.attr,
5181         &dev_attr_over_current.attr,
5182         &dev_attr_regulation_out.attr,
5183         &dev_attr_fail.attr,
5184         &dev_attr_over_temp.attr,
5185         &dev_attr_under_voltage_warn.attr,
5186         &dev_attr_over_current_warn.attr,
5187         &dev_attr_over_voltage_warn.attr,
5188         &dev_attr_over_temp_warn.attr,
5189         &dev_attr_suspend_standby_state.attr,
5190         &dev_attr_suspend_mem_state.attr,
5191         &dev_attr_suspend_disk_state.attr,
5192         &dev_attr_suspend_standby_microvolts.attr,
5193         &dev_attr_suspend_mem_microvolts.attr,
5194         &dev_attr_suspend_disk_microvolts.attr,
5195         &dev_attr_suspend_standby_mode.attr,
5196         &dev_attr_suspend_mem_mode.attr,
5197         &dev_attr_suspend_disk_mode.attr,
5198         NULL
5199 };
5200
5201 /*
5202  * To avoid cluttering sysfs (and memory) with useless state, only
5203  * create attributes that can be meaningfully displayed.
5204  */
5205 static umode_t regulator_attr_is_visible(struct kobject *kobj,
5206                                          struct attribute *attr, int idx)
5207 {
5208         struct device *dev = kobj_to_dev(kobj);
5209         struct regulator_dev *rdev = dev_to_rdev(dev);
5210         const struct regulator_ops *ops = rdev->desc->ops;
5211         umode_t mode = attr->mode;
5212
5213         /* these three are always present */
5214         if (attr == &dev_attr_name.attr ||
5215             attr == &dev_attr_num_users.attr ||
5216             attr == &dev_attr_type.attr)
5217                 return mode;
5218
5219         /* some attributes need specific methods to be displayed */
5220         if (attr == &dev_attr_microvolts.attr) {
5221                 if ((ops->get_voltage && ops->get_voltage(rdev) >= 0) ||
5222                     (ops->get_voltage_sel && ops->get_voltage_sel(rdev) >= 0) ||
5223                     (ops->list_voltage && ops->list_voltage(rdev, 0) >= 0) ||
5224                     (rdev->desc->fixed_uV && rdev->desc->n_voltages == 1))
5225                         return mode;
5226                 return 0;
5227         }
5228
5229         if (attr == &dev_attr_microamps.attr)
5230                 return ops->get_current_limit ? mode : 0;
5231
5232         if (attr == &dev_attr_opmode.attr)
5233                 return ops->get_mode ? mode : 0;
5234
5235         if (attr == &dev_attr_state.attr)
5236                 return (rdev->ena_pin || ops->is_enabled) ? mode : 0;
5237
5238         if (attr == &dev_attr_status.attr)
5239                 return ops->get_status ? mode : 0;
5240
5241         if (attr == &dev_attr_bypass.attr)
5242                 return ops->get_bypass ? mode : 0;
5243
5244         if (attr == &dev_attr_under_voltage.attr ||
5245             attr == &dev_attr_over_current.attr ||
5246             attr == &dev_attr_regulation_out.attr ||
5247             attr == &dev_attr_fail.attr ||
5248             attr == &dev_attr_over_temp.attr ||
5249             attr == &dev_attr_under_voltage_warn.attr ||
5250             attr == &dev_attr_over_current_warn.attr ||
5251             attr == &dev_attr_over_voltage_warn.attr ||
5252             attr == &dev_attr_over_temp_warn.attr)
5253                 return ops->get_error_flags ? mode : 0;
5254
5255         /* constraints need specific supporting methods */
5256         if (attr == &dev_attr_min_microvolts.attr ||
5257             attr == &dev_attr_max_microvolts.attr)
5258                 return (ops->set_voltage || ops->set_voltage_sel) ? mode : 0;
5259
5260         if (attr == &dev_attr_min_microamps.attr ||
5261             attr == &dev_attr_max_microamps.attr)
5262                 return ops->set_current_limit ? mode : 0;
5263
5264         if (attr == &dev_attr_suspend_standby_state.attr ||
5265             attr == &dev_attr_suspend_mem_state.attr ||
5266             attr == &dev_attr_suspend_disk_state.attr)
5267                 return mode;
5268
5269         if (attr == &dev_attr_suspend_standby_microvolts.attr ||
5270             attr == &dev_attr_suspend_mem_microvolts.attr ||
5271             attr == &dev_attr_suspend_disk_microvolts.attr)
5272                 return ops->set_suspend_voltage ? mode : 0;
5273
5274         if (attr == &dev_attr_suspend_standby_mode.attr ||
5275             attr == &dev_attr_suspend_mem_mode.attr ||
5276             attr == &dev_attr_suspend_disk_mode.attr)
5277                 return ops->set_suspend_mode ? mode : 0;
5278
5279         return mode;
5280 }
5281
5282 static const struct attribute_group regulator_dev_group = {
5283         .attrs = regulator_dev_attrs,
5284         .is_visible = regulator_attr_is_visible,
5285 };
5286
5287 static const struct attribute_group *regulator_dev_groups[] = {
5288         &regulator_dev_group,
5289         NULL
5290 };
5291
5292 static void regulator_dev_release(struct device *dev)
5293 {
5294         struct regulator_dev *rdev = dev_get_drvdata(dev);
5295
5296         debugfs_remove_recursive(rdev->debugfs);
5297         kfree(rdev->constraints);
5298         of_node_put(rdev->dev.of_node);
5299         kfree(rdev);
5300 }
5301
5302 static void rdev_init_debugfs(struct regulator_dev *rdev)
5303 {
5304         struct device *parent = rdev->dev.parent;
5305         const char *rname = rdev_get_name(rdev);
5306         char name[NAME_MAX];
5307
5308         /* Avoid duplicate debugfs directory names */
5309         if (parent && rname == rdev->desc->name) {
5310                 snprintf(name, sizeof(name), "%s-%s", dev_name(parent),
5311                          rname);
5312                 rname = name;
5313         }
5314
5315         rdev->debugfs = debugfs_create_dir(rname, debugfs_root);
5316         if (IS_ERR(rdev->debugfs))
5317                 rdev_dbg(rdev, "Failed to create debugfs directory\n");
5318
5319         debugfs_create_u32("use_count", 0444, rdev->debugfs,
5320                            &rdev->use_count);
5321         debugfs_create_u32("open_count", 0444, rdev->debugfs,
5322                            &rdev->open_count);
5323         debugfs_create_u32("bypass_count", 0444, rdev->debugfs,
5324                            &rdev->bypass_count);
5325 }
5326
5327 static int regulator_register_resolve_supply(struct device *dev, void *data)
5328 {
5329         struct regulator_dev *rdev = dev_to_rdev(dev);
5330
5331         if (regulator_resolve_supply(rdev))
5332                 rdev_dbg(rdev, "unable to resolve supply\n");
5333
5334         return 0;
5335 }
5336
5337 int regulator_coupler_register(struct regulator_coupler *coupler)
5338 {
5339         mutex_lock(&regulator_list_mutex);
5340         list_add_tail(&coupler->list, &regulator_coupler_list);
5341         mutex_unlock(&regulator_list_mutex);
5342
5343         return 0;
5344 }
5345
5346 static struct regulator_coupler *
5347 regulator_find_coupler(struct regulator_dev *rdev)
5348 {
5349         struct regulator_coupler *coupler;
5350         int err;
5351
5352         /*
5353          * Note that regulators are appended to the list and the generic
5354          * coupler is registered first, hence it will be attached at last
5355          * if nobody cared.
5356          */
5357         list_for_each_entry_reverse(coupler, &regulator_coupler_list, list) {
5358                 err = coupler->attach_regulator(coupler, rdev);
5359                 if (!err) {
5360                         if (!coupler->balance_voltage &&
5361                             rdev->coupling_desc.n_coupled > 2)
5362                                 goto err_unsupported;
5363
5364                         return coupler;
5365                 }
5366
5367                 if (err < 0)
5368                         return ERR_PTR(err);
5369
5370                 if (err == 1)
5371                         continue;
5372
5373                 break;
5374         }
5375
5376         return ERR_PTR(-EINVAL);
5377
5378 err_unsupported:
5379         if (coupler->detach_regulator)
5380                 coupler->detach_regulator(coupler, rdev);
5381
5382         rdev_err(rdev,
5383                 "Voltage balancing for multiple regulator couples is unimplemented\n");
5384
5385         return ERR_PTR(-EPERM);
5386 }
5387
5388 static void regulator_resolve_coupling(struct regulator_dev *rdev)
5389 {
5390         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5391         struct coupling_desc *c_desc = &rdev->coupling_desc;
5392         int n_coupled = c_desc->n_coupled;
5393         struct regulator_dev *c_rdev;
5394         int i;
5395
5396         for (i = 1; i < n_coupled; i++) {
5397                 /* already resolved */
5398                 if (c_desc->coupled_rdevs[i])
5399                         continue;
5400
5401                 c_rdev = of_parse_coupled_regulator(rdev, i - 1);
5402
5403                 if (!c_rdev)
5404                         continue;
5405
5406                 if (c_rdev->coupling_desc.coupler != coupler) {
5407                         rdev_err(rdev, "coupler mismatch with %s\n",
5408                                  rdev_get_name(c_rdev));
5409                         return;
5410                 }
5411
5412                 c_desc->coupled_rdevs[i] = c_rdev;
5413                 c_desc->n_resolved++;
5414
5415                 regulator_resolve_coupling(c_rdev);
5416         }
5417 }
5418
5419 static void regulator_remove_coupling(struct regulator_dev *rdev)
5420 {
5421         struct regulator_coupler *coupler = rdev->coupling_desc.coupler;
5422         struct coupling_desc *__c_desc, *c_desc = &rdev->coupling_desc;
5423         struct regulator_dev *__c_rdev, *c_rdev;
5424         unsigned int __n_coupled, n_coupled;
5425         int i, k;
5426         int err;
5427
5428         n_coupled = c_desc->n_coupled;
5429
5430         for (i = 1; i < n_coupled; i++) {
5431                 c_rdev = c_desc->coupled_rdevs[i];
5432
5433                 if (!c_rdev)
5434                         continue;
5435
5436                 regulator_lock(c_rdev);
5437
5438                 __c_desc = &c_rdev->coupling_desc;
5439                 __n_coupled = __c_desc->n_coupled;
5440
5441                 for (k = 1; k < __n_coupled; k++) {
5442                         __c_rdev = __c_desc->coupled_rdevs[k];
5443
5444                         if (__c_rdev == rdev) {
5445                                 __c_desc->coupled_rdevs[k] = NULL;
5446                                 __c_desc->n_resolved--;
5447                                 break;
5448                         }
5449                 }
5450
5451                 regulator_unlock(c_rdev);
5452
5453                 c_desc->coupled_rdevs[i] = NULL;
5454                 c_desc->n_resolved--;
5455         }
5456
5457         if (coupler && coupler->detach_regulator) {
5458                 err = coupler->detach_regulator(coupler, rdev);
5459                 if (err)
5460                         rdev_err(rdev, "failed to detach from coupler: %pe\n",
5461                                  ERR_PTR(err));
5462         }
5463
5464         kfree(rdev->coupling_desc.coupled_rdevs);
5465         rdev->coupling_desc.coupled_rdevs = NULL;
5466 }
5467
5468 static int regulator_init_coupling(struct regulator_dev *rdev)
5469 {
5470         struct regulator_dev **coupled;
5471         int err, n_phandles;
5472
5473         if (!IS_ENABLED(CONFIG_OF))
5474                 n_phandles = 0;
5475         else
5476                 n_phandles = of_get_n_coupled(rdev);
5477
5478         coupled = kcalloc(n_phandles + 1, sizeof(*coupled), GFP_KERNEL);
5479         if (!coupled)
5480                 return -ENOMEM;
5481
5482         rdev->coupling_desc.coupled_rdevs = coupled;
5483
5484         /*
5485          * Every regulator should always have coupling descriptor filled with
5486          * at least pointer to itself.
5487          */
5488         rdev->coupling_desc.coupled_rdevs[0] = rdev;
5489         rdev->coupling_desc.n_coupled = n_phandles + 1;
5490         rdev->coupling_desc.n_resolved++;
5491
5492         /* regulator isn't coupled */
5493         if (n_phandles == 0)
5494                 return 0;
5495
5496         if (!of_check_coupling_data(rdev))
5497                 return -EPERM;
5498
5499         mutex_lock(&regulator_list_mutex);
5500         rdev->coupling_desc.coupler = regulator_find_coupler(rdev);
5501         mutex_unlock(&regulator_list_mutex);
5502
5503         if (IS_ERR(rdev->coupling_desc.coupler)) {
5504                 err = PTR_ERR(rdev->coupling_desc.coupler);
5505                 rdev_err(rdev, "failed to get coupler: %pe\n", ERR_PTR(err));
5506                 return err;
5507         }
5508
5509         return 0;
5510 }
5511
5512 static int generic_coupler_attach(struct regulator_coupler *coupler,
5513                                   struct regulator_dev *rdev)
5514 {
5515         if (rdev->coupling_desc.n_coupled > 2) {
5516                 rdev_err(rdev,
5517                          "Voltage balancing for multiple regulator couples is unimplemented\n");
5518                 return -EPERM;
5519         }
5520
5521         if (!rdev->constraints->always_on) {
5522                 rdev_err(rdev,
5523                          "Coupling of a non always-on regulator is unimplemented\n");
5524                 return -ENOTSUPP;
5525         }
5526
5527         return 0;
5528 }
5529
5530 static struct regulator_coupler generic_regulator_coupler = {
5531         .attach_regulator = generic_coupler_attach,
5532 };
5533
5534 /**
5535  * regulator_register - register regulator
5536  * @dev: the device that drive the regulator
5537  * @regulator_desc: regulator to register
5538  * @cfg: runtime configuration for regulator
5539  *
5540  * Called by regulator drivers to register a regulator.
5541  * Returns a valid pointer to struct regulator_dev on success
5542  * or an ERR_PTR() on error.
5543  */
5544 struct regulator_dev *
5545 regulator_register(struct device *dev,
5546                    const struct regulator_desc *regulator_desc,
5547                    const struct regulator_config *cfg)
5548 {
5549         const struct regulator_init_data *init_data;
5550         struct regulator_config *config = NULL;
5551         static atomic_t regulator_no = ATOMIC_INIT(-1);
5552         struct regulator_dev *rdev;
5553         bool dangling_cfg_gpiod = false;
5554         bool dangling_of_gpiod = false;
5555         int ret, i;
5556         bool resolved_early = false;
5557
5558         if (cfg == NULL)
5559                 return ERR_PTR(-EINVAL);
5560         if (cfg->ena_gpiod)
5561                 dangling_cfg_gpiod = true;
5562         if (regulator_desc == NULL) {
5563                 ret = -EINVAL;
5564                 goto rinse;
5565         }
5566
5567         WARN_ON(!dev || !cfg->dev);
5568
5569         if (regulator_desc->name == NULL || regulator_desc->ops == NULL) {
5570                 ret = -EINVAL;
5571                 goto rinse;
5572         }
5573
5574         if (regulator_desc->type != REGULATOR_VOLTAGE &&
5575             regulator_desc->type != REGULATOR_CURRENT) {
5576                 ret = -EINVAL;
5577                 goto rinse;
5578         }
5579
5580         /* Only one of each should be implemented */
5581         WARN_ON(regulator_desc->ops->get_voltage &&
5582                 regulator_desc->ops->get_voltage_sel);
5583         WARN_ON(regulator_desc->ops->set_voltage &&
5584                 regulator_desc->ops->set_voltage_sel);
5585
5586         /* If we're using selectors we must implement list_voltage. */
5587         if (regulator_desc->ops->get_voltage_sel &&
5588             !regulator_desc->ops->list_voltage) {
5589                 ret = -EINVAL;
5590                 goto rinse;
5591         }
5592         if (regulator_desc->ops->set_voltage_sel &&
5593             !regulator_desc->ops->list_voltage) {
5594                 ret = -EINVAL;
5595                 goto rinse;
5596         }
5597
5598         rdev = kzalloc(sizeof(struct regulator_dev), GFP_KERNEL);
5599         if (rdev == NULL) {
5600                 ret = -ENOMEM;
5601                 goto rinse;
5602         }
5603         device_initialize(&rdev->dev);
5604         dev_set_drvdata(&rdev->dev, rdev);
5605         rdev->dev.class = &regulator_class;
5606         spin_lock_init(&rdev->err_lock);
5607
5608         /*
5609          * Duplicate the config so the driver could override it after
5610          * parsing init data.
5611          */
5612         config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
5613         if (config == NULL) {
5614                 ret = -ENOMEM;
5615                 goto clean;
5616         }
5617
5618         init_data = regulator_of_get_init_data(dev, regulator_desc, config,
5619                                                &rdev->dev.of_node);
5620
5621         /*
5622          * Sometimes not all resources are probed already so we need to take
5623          * that into account. This happens most the time if the ena_gpiod comes
5624          * from a gpio extender or something else.
5625          */
5626         if (PTR_ERR(init_data) == -EPROBE_DEFER) {
5627                 ret = -EPROBE_DEFER;
5628                 goto clean;
5629         }
5630
5631         /*
5632          * We need to keep track of any GPIO descriptor coming from the
5633          * device tree until we have handled it over to the core. If the
5634          * config that was passed in to this function DOES NOT contain
5635          * a descriptor, and the config after this call DOES contain
5636          * a descriptor, we definitely got one from parsing the device
5637          * tree.
5638          */
5639         if (!cfg->ena_gpiod && config->ena_gpiod)
5640                 dangling_of_gpiod = true;
5641         if (!init_data) {
5642                 init_data = config->init_data;
5643                 rdev->dev.of_node = of_node_get(config->of_node);
5644         }
5645
5646         ww_mutex_init(&rdev->mutex, &regulator_ww_class);
5647         rdev->reg_data = config->driver_data;
5648         rdev->owner = regulator_desc->owner;
5649         rdev->desc = regulator_desc;
5650         if (config->regmap)
5651                 rdev->regmap = config->regmap;
5652         else if (dev_get_regmap(dev, NULL))
5653                 rdev->regmap = dev_get_regmap(dev, NULL);
5654         else if (dev->parent)
5655                 rdev->regmap = dev_get_regmap(dev->parent, NULL);
5656         INIT_LIST_HEAD(&rdev->consumer_list);
5657         INIT_LIST_HEAD(&rdev->list);
5658         BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier);
5659         INIT_DELAYED_WORK(&rdev->disable_work, regulator_disable_work);
5660
5661         if (init_data && init_data->supply_regulator)
5662                 rdev->supply_name = init_data->supply_regulator;
5663         else if (regulator_desc->supply_name)
5664                 rdev->supply_name = regulator_desc->supply_name;
5665
5666         /* register with sysfs */
5667         rdev->dev.parent = config->dev;
5668         dev_set_name(&rdev->dev, "regulator.%lu",
5669                     (unsigned long) atomic_inc_return(&regulator_no));
5670
5671         /* set regulator constraints */
5672         if (init_data)
5673                 rdev->constraints = kmemdup(&init_data->constraints,
5674                                             sizeof(*rdev->constraints),
5675                                             GFP_KERNEL);
5676         else
5677                 rdev->constraints = kzalloc(sizeof(*rdev->constraints),
5678                                             GFP_KERNEL);
5679         if (!rdev->constraints) {
5680                 ret = -ENOMEM;
5681                 goto wash;
5682         }
5683
5684         if ((rdev->supply_name && !rdev->supply) &&
5685                 (rdev->constraints->always_on ||
5686                  rdev->constraints->boot_on)) {
5687                 ret = regulator_resolve_supply(rdev);
5688                 if (ret)
5689                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5690                                          ERR_PTR(ret));
5691
5692                 resolved_early = true;
5693         }
5694
5695         /* perform any regulator specific init */
5696         if (init_data && init_data->regulator_init) {
5697                 ret = init_data->regulator_init(rdev->reg_data);
5698                 if (ret < 0)
5699                         goto wash;
5700         }
5701
5702         if (config->ena_gpiod) {
5703                 ret = regulator_ena_gpio_request(rdev, config);
5704                 if (ret != 0) {
5705                         rdev_err(rdev, "Failed to request enable GPIO: %pe\n",
5706                                  ERR_PTR(ret));
5707                         goto wash;
5708                 }
5709                 /* The regulator core took over the GPIO descriptor */
5710                 dangling_cfg_gpiod = false;
5711                 dangling_of_gpiod = false;
5712         }
5713
5714         ret = set_machine_constraints(rdev);
5715         if (ret == -EPROBE_DEFER && !resolved_early) {
5716                 /* Regulator might be in bypass mode and so needs its supply
5717                  * to set the constraints
5718                  */
5719                 /* FIXME: this currently triggers a chicken-and-egg problem
5720                  * when creating -SUPPLY symlink in sysfs to a regulator
5721                  * that is just being created
5722                  */
5723                 rdev_dbg(rdev, "will resolve supply early: %s\n",
5724                          rdev->supply_name);
5725                 ret = regulator_resolve_supply(rdev);
5726                 if (!ret)
5727                         ret = set_machine_constraints(rdev);
5728                 else
5729                         rdev_dbg(rdev, "unable to resolve supply early: %pe\n",
5730                                  ERR_PTR(ret));
5731         }
5732         if (ret < 0)
5733                 goto wash;
5734
5735         ret = regulator_init_coupling(rdev);
5736         if (ret < 0)
5737                 goto wash;
5738
5739         /* add consumers devices */
5740         if (init_data) {
5741                 for (i = 0; i < init_data->num_consumer_supplies; i++) {
5742                         ret = set_consumer_device_supply(rdev,
5743                                 init_data->consumer_supplies[i].dev_name,
5744                                 init_data->consumer_supplies[i].supply);
5745                         if (ret < 0) {
5746                                 dev_err(dev, "Failed to set supply %s\n",
5747                                         init_data->consumer_supplies[i].supply);
5748                                 goto unset_supplies;
5749                         }
5750                 }
5751         }
5752
5753         if (!rdev->desc->ops->get_voltage &&
5754             !rdev->desc->ops->list_voltage &&
5755             !rdev->desc->fixed_uV)
5756                 rdev->is_switch = true;
5757
5758         ret = device_add(&rdev->dev);
5759         if (ret != 0)
5760                 goto unset_supplies;
5761
5762         rdev_init_debugfs(rdev);
5763
5764         /* try to resolve regulators coupling since a new one was registered */
5765         mutex_lock(&regulator_list_mutex);
5766         regulator_resolve_coupling(rdev);
5767         mutex_unlock(&regulator_list_mutex);
5768
5769         /* try to resolve regulators supply since a new one was registered */
5770         class_for_each_device(&regulator_class, NULL, NULL,
5771                               regulator_register_resolve_supply);
5772         kfree(config);
5773         return rdev;
5774
5775 unset_supplies:
5776         mutex_lock(&regulator_list_mutex);
5777         unset_regulator_supplies(rdev);
5778         regulator_remove_coupling(rdev);
5779         mutex_unlock(&regulator_list_mutex);
5780 wash:
5781         regulator_put(rdev->supply);
5782         kfree(rdev->coupling_desc.coupled_rdevs);
5783         mutex_lock(&regulator_list_mutex);
5784         regulator_ena_gpio_free(rdev);
5785         mutex_unlock(&regulator_list_mutex);
5786 clean:
5787         if (dangling_of_gpiod)
5788                 gpiod_put(config->ena_gpiod);
5789         kfree(config);
5790         put_device(&rdev->dev);
5791 rinse:
5792         if (dangling_cfg_gpiod)
5793                 gpiod_put(cfg->ena_gpiod);
5794         return ERR_PTR(ret);
5795 }
5796 EXPORT_SYMBOL_GPL(regulator_register);
5797
5798 /**
5799  * regulator_unregister - unregister regulator
5800  * @rdev: regulator to unregister
5801  *
5802  * Called by regulator drivers to unregister a regulator.
5803  */
5804 void regulator_unregister(struct regulator_dev *rdev)
5805 {
5806         if (rdev == NULL)
5807                 return;
5808
5809         if (rdev->supply) {
5810                 while (rdev->use_count--)
5811                         regulator_disable(rdev->supply);
5812                 regulator_put(rdev->supply);
5813         }
5814
5815         flush_work(&rdev->disable_work.work);
5816
5817         mutex_lock(&regulator_list_mutex);
5818
5819         WARN_ON(rdev->open_count);
5820         regulator_remove_coupling(rdev);
5821         unset_regulator_supplies(rdev);
5822         list_del(&rdev->list);
5823         regulator_ena_gpio_free(rdev);
5824         device_unregister(&rdev->dev);
5825
5826         mutex_unlock(&regulator_list_mutex);
5827 }
5828 EXPORT_SYMBOL_GPL(regulator_unregister);
5829
5830 #ifdef CONFIG_SUSPEND
5831 /**
5832  * regulator_suspend - prepare regulators for system wide suspend
5833  * @dev: ``&struct device`` pointer that is passed to _regulator_suspend()
5834  *
5835  * Configure each regulator with it's suspend operating parameters for state.
5836  */
5837 static int regulator_suspend(struct device *dev)
5838 {
5839         struct regulator_dev *rdev = dev_to_rdev(dev);
5840         suspend_state_t state = pm_suspend_target_state;
5841         int ret;
5842         const struct regulator_state *rstate;
5843
5844         rstate = regulator_get_suspend_state_check(rdev, state);
5845         if (!rstate)
5846                 return 0;
5847
5848         regulator_lock(rdev);
5849         ret = __suspend_set_state(rdev, rstate);
5850         regulator_unlock(rdev);
5851
5852         return ret;
5853 }
5854
5855 static int regulator_resume(struct device *dev)
5856 {
5857         suspend_state_t state = pm_suspend_target_state;
5858         struct regulator_dev *rdev = dev_to_rdev(dev);
5859         struct regulator_state *rstate;
5860         int ret = 0;
5861
5862         rstate = regulator_get_suspend_state(rdev, state);
5863         if (rstate == NULL)
5864                 return 0;
5865
5866         /* Avoid grabbing the lock if we don't need to */
5867         if (!rdev->desc->ops->resume)
5868                 return 0;
5869
5870         regulator_lock(rdev);
5871
5872         if (rstate->enabled == ENABLE_IN_SUSPEND ||
5873             rstate->enabled == DISABLE_IN_SUSPEND)
5874                 ret = rdev->desc->ops->resume(rdev);
5875
5876         regulator_unlock(rdev);
5877
5878         return ret;
5879 }
5880 #else /* !CONFIG_SUSPEND */
5881
5882 #define regulator_suspend       NULL
5883 #define regulator_resume        NULL
5884
5885 #endif /* !CONFIG_SUSPEND */
5886
5887 #ifdef CONFIG_PM
5888 static const struct dev_pm_ops __maybe_unused regulator_pm_ops = {
5889         .suspend        = regulator_suspend,
5890         .resume         = regulator_resume,
5891 };
5892 #endif
5893
5894 struct class regulator_class = {
5895         .name = "regulator",
5896         .dev_release = regulator_dev_release,
5897         .dev_groups = regulator_dev_groups,
5898 #ifdef CONFIG_PM
5899         .pm = &regulator_pm_ops,
5900 #endif
5901 };
5902 /**
5903  * regulator_has_full_constraints - the system has fully specified constraints
5904  *
5905  * Calling this function will cause the regulator API to disable all
5906  * regulators which have a zero use count and don't have an always_on
5907  * constraint in a late_initcall.
5908  *
5909  * The intention is that this will become the default behaviour in a
5910  * future kernel release so users are encouraged to use this facility
5911  * now.
5912  */
5913 void regulator_has_full_constraints(void)
5914 {
5915         has_full_constraints = 1;
5916 }
5917 EXPORT_SYMBOL_GPL(regulator_has_full_constraints);
5918
5919 /**
5920  * rdev_get_drvdata - get rdev regulator driver data
5921  * @rdev: regulator
5922  *
5923  * Get rdev regulator driver private data. This call can be used in the
5924  * regulator driver context.
5925  */
5926 void *rdev_get_drvdata(struct regulator_dev *rdev)
5927 {
5928         return rdev->reg_data;
5929 }
5930 EXPORT_SYMBOL_GPL(rdev_get_drvdata);
5931
5932 /**
5933  * regulator_get_drvdata - get regulator driver data
5934  * @regulator: regulator
5935  *
5936  * Get regulator driver private data. This call can be used in the consumer
5937  * driver context when non API regulator specific functions need to be called.
5938  */
5939 void *regulator_get_drvdata(struct regulator *regulator)
5940 {
5941         return regulator->rdev->reg_data;
5942 }
5943 EXPORT_SYMBOL_GPL(regulator_get_drvdata);
5944
5945 /**
5946  * regulator_set_drvdata - set regulator driver data
5947  * @regulator: regulator
5948  * @data: data
5949  */
5950 void regulator_set_drvdata(struct regulator *regulator, void *data)
5951 {
5952         regulator->rdev->reg_data = data;
5953 }
5954 EXPORT_SYMBOL_GPL(regulator_set_drvdata);
5955
5956 /**
5957  * rdev_get_id - get regulator ID
5958  * @rdev: regulator
5959  */
5960 int rdev_get_id(struct regulator_dev *rdev)
5961 {
5962         return rdev->desc->id;
5963 }
5964 EXPORT_SYMBOL_GPL(rdev_get_id);
5965
5966 struct device *rdev_get_dev(struct regulator_dev *rdev)
5967 {
5968         return &rdev->dev;
5969 }
5970 EXPORT_SYMBOL_GPL(rdev_get_dev);
5971
5972 struct regmap *rdev_get_regmap(struct regulator_dev *rdev)
5973 {
5974         return rdev->regmap;
5975 }
5976 EXPORT_SYMBOL_GPL(rdev_get_regmap);
5977
5978 void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data)
5979 {
5980         return reg_init_data->driver_data;
5981 }
5982 EXPORT_SYMBOL_GPL(regulator_get_init_drvdata);
5983
5984 #ifdef CONFIG_DEBUG_FS
5985 static int supply_map_show(struct seq_file *sf, void *data)
5986 {
5987         struct regulator_map *map;
5988
5989         list_for_each_entry(map, &regulator_map_list, list) {
5990                 seq_printf(sf, "%s -> %s.%s\n",
5991                                 rdev_get_name(map->regulator), map->dev_name,
5992                                 map->supply);
5993         }
5994
5995         return 0;
5996 }
5997 DEFINE_SHOW_ATTRIBUTE(supply_map);
5998
5999 struct summary_data {
6000         struct seq_file *s;
6001         struct regulator_dev *parent;
6002         int level;
6003 };
6004
6005 static void regulator_summary_show_subtree(struct seq_file *s,
6006                                            struct regulator_dev *rdev,
6007                                            int level);
6008
6009 static int regulator_summary_show_children(struct device *dev, void *data)
6010 {
6011         struct regulator_dev *rdev = dev_to_rdev(dev);
6012         struct summary_data *summary_data = data;
6013
6014         if (rdev->supply && rdev->supply->rdev == summary_data->parent)
6015                 regulator_summary_show_subtree(summary_data->s, rdev,
6016                                                summary_data->level + 1);
6017
6018         return 0;
6019 }
6020
6021 static void regulator_summary_show_subtree(struct seq_file *s,
6022                                            struct regulator_dev *rdev,
6023                                            int level)
6024 {
6025         struct regulation_constraints *c;
6026         struct regulator *consumer;
6027         struct summary_data summary_data;
6028         unsigned int opmode;
6029
6030         if (!rdev)
6031                 return;
6032
6033         opmode = _regulator_get_mode_unlocked(rdev);
6034         seq_printf(s, "%*s%-*s %3d %4d %6d %7s ",
6035                    level * 3 + 1, "",
6036                    30 - level * 3, rdev_get_name(rdev),
6037                    rdev->use_count, rdev->open_count, rdev->bypass_count,
6038                    regulator_opmode_to_str(opmode));
6039
6040         seq_printf(s, "%5dmV ", regulator_get_voltage_rdev(rdev) / 1000);
6041         seq_printf(s, "%5dmA ",
6042                    _regulator_get_current_limit_unlocked(rdev) / 1000);
6043
6044         c = rdev->constraints;
6045         if (c) {
6046                 switch (rdev->desc->type) {
6047                 case REGULATOR_VOLTAGE:
6048                         seq_printf(s, "%5dmV %5dmV ",
6049                                    c->min_uV / 1000, c->max_uV / 1000);
6050                         break;
6051                 case REGULATOR_CURRENT:
6052                         seq_printf(s, "%5dmA %5dmA ",
6053                                    c->min_uA / 1000, c->max_uA / 1000);
6054                         break;
6055                 }
6056         }
6057
6058         seq_puts(s, "\n");
6059
6060         list_for_each_entry(consumer, &rdev->consumer_list, list) {
6061                 if (consumer->dev && consumer->dev->class == &regulator_class)
6062                         continue;
6063
6064                 seq_printf(s, "%*s%-*s ",
6065                            (level + 1) * 3 + 1, "",
6066                            30 - (level + 1) * 3,
6067                            consumer->supply_name ? consumer->supply_name :
6068                            consumer->dev ? dev_name(consumer->dev) : "deviceless");
6069
6070                 switch (rdev->desc->type) {
6071                 case REGULATOR_VOLTAGE:
6072                         seq_printf(s, "%3d %33dmA%c%5dmV %5dmV",
6073                                    consumer->enable_count,
6074                                    consumer->uA_load / 1000,
6075                                    consumer->uA_load && !consumer->enable_count ?
6076                                    '*' : ' ',
6077                                    consumer->voltage[PM_SUSPEND_ON].min_uV / 1000,
6078                                    consumer->voltage[PM_SUSPEND_ON].max_uV / 1000);
6079                         break;
6080                 case REGULATOR_CURRENT:
6081                         break;
6082                 }
6083
6084                 seq_puts(s, "\n");
6085         }
6086
6087         summary_data.s = s;
6088         summary_data.level = level;
6089         summary_data.parent = rdev;
6090
6091         class_for_each_device(&regulator_class, NULL, &summary_data,
6092                               regulator_summary_show_children);
6093 }
6094
6095 struct summary_lock_data {
6096         struct ww_acquire_ctx *ww_ctx;
6097         struct regulator_dev **new_contended_rdev;
6098         struct regulator_dev **old_contended_rdev;
6099 };
6100
6101 static int regulator_summary_lock_one(struct device *dev, void *data)
6102 {
6103         struct regulator_dev *rdev = dev_to_rdev(dev);
6104         struct summary_lock_data *lock_data = data;
6105         int ret = 0;
6106
6107         if (rdev != *lock_data->old_contended_rdev) {
6108                 ret = regulator_lock_nested(rdev, lock_data->ww_ctx);
6109
6110                 if (ret == -EDEADLK)
6111                         *lock_data->new_contended_rdev = rdev;
6112                 else
6113                         WARN_ON_ONCE(ret);
6114         } else {
6115                 *lock_data->old_contended_rdev = NULL;
6116         }
6117
6118         return ret;
6119 }
6120
6121 static int regulator_summary_unlock_one(struct device *dev, void *data)
6122 {
6123         struct regulator_dev *rdev = dev_to_rdev(dev);
6124         struct summary_lock_data *lock_data = data;
6125
6126         if (lock_data) {
6127                 if (rdev == *lock_data->new_contended_rdev)
6128                         return -EDEADLK;
6129         }
6130
6131         regulator_unlock(rdev);
6132
6133         return 0;
6134 }
6135
6136 static int regulator_summary_lock_all(struct ww_acquire_ctx *ww_ctx,
6137                                       struct regulator_dev **new_contended_rdev,
6138                                       struct regulator_dev **old_contended_rdev)
6139 {
6140         struct summary_lock_data lock_data;
6141         int ret;
6142
6143         lock_data.ww_ctx = ww_ctx;
6144         lock_data.new_contended_rdev = new_contended_rdev;
6145         lock_data.old_contended_rdev = old_contended_rdev;
6146
6147         ret = class_for_each_device(&regulator_class, NULL, &lock_data,
6148                                     regulator_summary_lock_one);
6149         if (ret)
6150                 class_for_each_device(&regulator_class, NULL, &lock_data,
6151                                       regulator_summary_unlock_one);
6152
6153         return ret;
6154 }
6155
6156 static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
6157 {
6158         struct regulator_dev *new_contended_rdev = NULL;
6159         struct regulator_dev *old_contended_rdev = NULL;
6160         int err;
6161
6162         mutex_lock(&regulator_list_mutex);
6163
6164         ww_acquire_init(ww_ctx, &regulator_ww_class);
6165
6166         do {
6167                 if (new_contended_rdev) {
6168                         ww_mutex_lock_slow(&new_contended_rdev->mutex, ww_ctx);
6169                         old_contended_rdev = new_contended_rdev;
6170                         old_contended_rdev->ref_cnt++;
6171                         old_contended_rdev->mutex_owner = current;
6172                 }
6173
6174                 err = regulator_summary_lock_all(ww_ctx,
6175                                                  &new_contended_rdev,
6176                                                  &old_contended_rdev);
6177
6178                 if (old_contended_rdev)
6179                         regulator_unlock(old_contended_rdev);
6180
6181         } while (err == -EDEADLK);
6182
6183         ww_acquire_done(ww_ctx);
6184 }
6185
6186 static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
6187 {
6188         class_for_each_device(&regulator_class, NULL, NULL,
6189                               regulator_summary_unlock_one);
6190         ww_acquire_fini(ww_ctx);
6191
6192         mutex_unlock(&regulator_list_mutex);
6193 }
6194
6195 static int regulator_summary_show_roots(struct device *dev, void *data)
6196 {
6197         struct regulator_dev *rdev = dev_to_rdev(dev);
6198         struct seq_file *s = data;
6199
6200         if (!rdev->supply)
6201                 regulator_summary_show_subtree(s, rdev, 0);
6202
6203         return 0;
6204 }
6205
6206 static int regulator_summary_show(struct seq_file *s, void *data)
6207 {
6208         struct ww_acquire_ctx ww_ctx;
6209
6210         seq_puts(s, " regulator                      use open bypass  opmode voltage current     min     max\n");
6211         seq_puts(s, "---------------------------------------------------------------------------------------\n");
6212
6213         regulator_summary_lock(&ww_ctx);
6214
6215         class_for_each_device(&regulator_class, NULL, s,
6216                               regulator_summary_show_roots);
6217
6218         regulator_summary_unlock(&ww_ctx);
6219
6220         return 0;
6221 }
6222 DEFINE_SHOW_ATTRIBUTE(regulator_summary);
6223 #endif /* CONFIG_DEBUG_FS */
6224
6225 static int __init regulator_init(void)
6226 {
6227         int ret;
6228
6229         ret = class_register(&regulator_class);
6230
6231         debugfs_root = debugfs_create_dir("regulator", NULL);
6232         if (IS_ERR(debugfs_root))
6233                 pr_debug("regulator: Failed to create debugfs directory\n");
6234
6235 #ifdef CONFIG_DEBUG_FS
6236         debugfs_create_file("supply_map", 0444, debugfs_root, NULL,
6237                             &supply_map_fops);
6238
6239         debugfs_create_file("regulator_summary", 0444, debugfs_root,
6240                             NULL, &regulator_summary_fops);
6241 #endif
6242         regulator_dummy_init();
6243
6244         regulator_coupler_register(&generic_regulator_coupler);
6245
6246         return ret;
6247 }
6248
6249 /* init early to allow our consumers to complete system booting */
6250 core_initcall(regulator_init);
6251
6252 static int regulator_late_cleanup(struct device *dev, void *data)
6253 {
6254         struct regulator_dev *rdev = dev_to_rdev(dev);
6255         struct regulation_constraints *c = rdev->constraints;
6256         int ret;
6257
6258         if (c && c->always_on)
6259                 return 0;
6260
6261         if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS))
6262                 return 0;
6263
6264         regulator_lock(rdev);
6265
6266         if (rdev->use_count)
6267                 goto unlock;
6268
6269         /* If reading the status failed, assume that it's off. */
6270         if (_regulator_is_enabled(rdev) <= 0)
6271                 goto unlock;
6272
6273         if (have_full_constraints()) {
6274                 /* We log since this may kill the system if it goes
6275                  * wrong.
6276                  */
6277                 rdev_info(rdev, "disabling\n");
6278                 ret = _regulator_do_disable(rdev);
6279                 if (ret != 0)
6280                         rdev_err(rdev, "couldn't disable: %pe\n", ERR_PTR(ret));
6281         } else {
6282                 /* The intention is that in future we will
6283                  * assume that full constraints are provided
6284                  * so warn even if we aren't going to do
6285                  * anything here.
6286                  */
6287                 rdev_warn(rdev, "incomplete constraints, leaving on\n");
6288         }
6289
6290 unlock:
6291         regulator_unlock(rdev);
6292
6293         return 0;
6294 }
6295
6296 static bool regulator_ignore_unused;
6297 static int __init regulator_ignore_unused_setup(char *__unused)
6298 {
6299         regulator_ignore_unused = true;
6300         return 1;
6301 }
6302 __setup("regulator_ignore_unused", regulator_ignore_unused_setup);
6303
6304 static void regulator_init_complete_work_function(struct work_struct *work)
6305 {
6306         /*
6307          * Regulators may had failed to resolve their input supplies
6308          * when were registered, either because the input supply was
6309          * not registered yet or because its parent device was not
6310          * bound yet. So attempt to resolve the input supplies for
6311          * pending regulators before trying to disable unused ones.
6312          */
6313         class_for_each_device(&regulator_class, NULL, NULL,
6314                               regulator_register_resolve_supply);
6315
6316         /*
6317          * For debugging purposes, it may be useful to prevent unused
6318          * regulators from being disabled.
6319          */
6320         if (regulator_ignore_unused) {
6321                 pr_warn("regulator: Not disabling unused regulators\n");
6322                 return;
6323         }
6324
6325         /* If we have a full configuration then disable any regulators
6326          * we have permission to change the status for and which are
6327          * not in use or always_on.  This is effectively the default
6328          * for DT and ACPI as they have full constraints.
6329          */
6330         class_for_each_device(&regulator_class, NULL, NULL,
6331                               regulator_late_cleanup);
6332 }
6333
6334 static DECLARE_DELAYED_WORK(regulator_init_complete_work,
6335                             regulator_init_complete_work_function);
6336
6337 static int __init regulator_init_complete(void)
6338 {
6339         /*
6340          * Since DT doesn't provide an idiomatic mechanism for
6341          * enabling full constraints and since it's much more natural
6342          * with DT to provide them just assume that a DT enabled
6343          * system has full constraints.
6344          */
6345         if (of_have_populated_dt())
6346                 has_full_constraints = true;
6347
6348         /*
6349          * We punt completion for an arbitrary amount of time since
6350          * systems like distros will load many drivers from userspace
6351          * so consumers might not always be ready yet, this is
6352          * particularly an issue with laptops where this might bounce
6353          * the display off then on.  Ideally we'd get a notification
6354          * from userspace when this happens but we don't so just wait
6355          * a bit and hope we waited long enough.  It'd be better if
6356          * we'd only do this on systems that need it, and a kernel
6357          * command line option might be useful.
6358          */
6359         schedule_delayed_work(&regulator_init_complete_work,
6360                               msecs_to_jiffies(30000));
6361
6362         return 0;
6363 }
6364 late_initcall_sync(regulator_init_complete);