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