drivers/power/supply/power_supply_core.c

   1 /*
   2  *  Universal power supply monitor class
   3  *
   4  *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
   5  *  Copyright © 2004  Szabolcs Gyurko
   6  *  Copyright © 2003  Ian Molton <spyro@f2s.com>
   7  *
   8  *  Modified: 2004, Oct     Szabolcs Gyurko
   9  *
  10  *  You may use this code as per GPL version 2
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/types.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/delay.h>
  18 #include <linux/device.h>
  19 #include <linux/notifier.h>
  20 #include <linux/err.h>
  21 #include <linux/power_supply.h>
  22 #include <linux/thermal.h>
  23 #include "power_supply.h"
  24
  25 /* exported for the APM Power driver, APM emulation */
  26 struct class *power_supply_class;
  27 EXPORT_SYMBOL_GPL(power_supply_class);
  28
  29 ATOMIC_NOTIFIER_HEAD(power_supply_notifier);
  30 EXPORT_SYMBOL_GPL(power_supply_notifier);
  31
  32 static struct device_type power_supply_dev_type;
  33
  34 #define POWER_SUPPLY_DEFERRED_REGISTER_TIME     msecs_to_jiffies(10)
  35
  36 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
  37                                          struct power_supply *supply)
  38 {
  39         int i;
  40
  41         if (!supply->supplied_from && !supplier->supplied_to)
  42                 return false;
  43
  44         /* Support both supplied_to and supplied_from modes */
  45         if (supply->supplied_from) {
  46                 if (!supplier->desc->name)
  47                         return false;
  48                 for (i = 0; i < supply->num_supplies; i++)
  49                         if (!strcmp(supplier->desc->name, supply->supplied_from[i]))
  50                                 return true;
  51         } else {
  52                 if (!supply->desc->name)
  53                         return false;
  54                 for (i = 0; i < supplier->num_supplicants; i++)
  55                         if (!strcmp(supplier->supplied_to[i], supply->desc->name))
  56                                 return true;
  57         }
  58
  59         return false;
  60 }
  61
  62 static int __power_supply_changed_work(struct device *dev, void *data)
  63 {
  64         struct power_supply *psy = data;
  65         struct power_supply *pst = dev_get_drvdata(dev);
  66
  67         if (__power_supply_is_supplied_by(psy, pst)) {
  68                 if (pst->desc->external_power_changed)
  69                         pst->desc->external_power_changed(pst);
  70         }
  71
  72         return 0;
  73 }
  74
  75 static void power_supply_changed_work(struct work_struct *work)
  76 {
  77         unsigned long flags;
  78         struct power_supply *psy = container_of(work, struct power_supply,
  79                                                 changed_work);
  80
  81         dev_dbg(&psy->dev, "%s\n", __func__);
  82
  83         spin_lock_irqsave(&psy->changed_lock, flags);
  84         /*
  85          * Check 'changed' here to avoid issues due to race between
  86          * power_supply_changed() and this routine. In worst case
  87          * power_supply_changed() can be called again just before we take above
  88          * lock. During the first call of this routine we will mark 'changed' as
  89          * false and it will stay false for the next call as well.
  90          */
  91         if (likely(psy->changed)) {
  92                 psy->changed = false;
  93                 spin_unlock_irqrestore(&psy->changed_lock, flags);
  94                 class_for_each_device(power_supply_class, NULL, psy,
  95                                       __power_supply_changed_work);
  96                 power_supply_update_leds(psy);
  97                 atomic_notifier_call_chain(&power_supply_notifier,
  98                                 PSY_EVENT_PROP_CHANGED, psy);
  99                 kobject_uevent(&psy->dev.kobj, KOBJ_CHANGE);
 100                 spin_lock_irqsave(&psy->changed_lock, flags);
 101         }
 102
 103         /*
 104          * Hold the wakeup_source until all events are processed.
 105          * power_supply_changed() might have called again and have set 'changed'
 106          * to true.
 107          */
 108         if (likely(!psy->changed))
 109                 pm_relax(&psy->dev);
 110         spin_unlock_irqrestore(&psy->changed_lock, flags);
 111 }
 112
 113 void power_supply_changed(struct power_supply *psy)
 114 {
 115         unsigned long flags;
 116
 117         dev_dbg(&psy->dev, "%s\n", __func__);
 118
 119         spin_lock_irqsave(&psy->changed_lock, flags);
 120         psy->changed = true;
 121         pm_stay_awake(&psy->dev);
 122         spin_unlock_irqrestore(&psy->changed_lock, flags);
 123         schedule_work(&psy->changed_work);
 124 }
 125 EXPORT_SYMBOL_GPL(power_supply_changed);
 126
 127 /*
 128  * Notify that power supply was registered after parent finished the probing.
 129  *
 130  * Often power supply is registered from driver's probe function. However
 131  * calling power_supply_changed() directly from power_supply_register()
 132  * would lead to execution of get_property() function provided by the driver
 133  * too early - before the probe ends.
 134  *
 135  * Avoid that by waiting on parent's mutex.
 136  */
 137 static void power_supply_deferred_register_work(struct work_struct *work)
 138 {
 139         struct power_supply *psy = container_of(work, struct power_supply,
 140                                                 deferred_register_work.work);
 141
 142         if (psy->dev.parent) {
 143                 while (!mutex_trylock(&psy->dev.parent->mutex)) {
 144                         if (psy->removing)
 145                                 return;
 146                         msleep(10);
 147                 }
 148         }
 149
 150         power_supply_changed(psy);
 151
 152         if (psy->dev.parent)
 153                 mutex_unlock(&psy->dev.parent->mutex);
 154 }
 155
 156 #ifdef CONFIG_OF
 157 #include <linux/of.h>
 158
 159 static int __power_supply_populate_supplied_from(struct device *dev,
 160                                                  void *data)
 161 {
 162         struct power_supply *psy = data;
 163         struct power_supply *epsy = dev_get_drvdata(dev);
 164         struct device_node *np;
 165         int i = 0;
 166
 167         do {
 168                 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
 169                 if (!np)
 170                         break;
 171
 172                 if (np == epsy->of_node) {
 173                         dev_info(&psy->dev, "%s: Found supply : %s\n",
 174                                 psy->desc->name, epsy->desc->name);
 175                         psy->supplied_from[i-1] = (char *)epsy->desc->name;
 176                         psy->num_supplies++;
 177                         of_node_put(np);
 178                         break;
 179                 }
 180                 of_node_put(np);
 181         } while (np);
 182
 183         return 0;
 184 }
 185
 186 static int power_supply_populate_supplied_from(struct power_supply *psy)
 187 {
 188         int error;
 189
 190         error = class_for_each_device(power_supply_class, NULL, psy,
 191                                       __power_supply_populate_supplied_from);
 192
 193         dev_dbg(&psy->dev, "%s %d\n", __func__, error);
 194
 195         return error;
 196 }
 197
 198 static int  __power_supply_find_supply_from_node(struct device *dev,
 199                                                  void *data)
 200 {
 201         struct device_node *np = data;
 202         struct power_supply *epsy = dev_get_drvdata(dev);
 203
 204         /* returning non-zero breaks out of class_for_each_device loop */
 205         if (epsy->of_node == np)
 206                 return 1;
 207
 208         return 0;
 209 }
 210
 211 static int power_supply_find_supply_from_node(struct device_node *supply_node)
 212 {
 213         int error;
 214
 215         /*
 216          * class_for_each_device() either returns its own errors or values
 217          * returned by __power_supply_find_supply_from_node().
 218          *
 219          * __power_supply_find_supply_from_node() will return 0 (no match)
 220          * or 1 (match).
 221          *
 222          * We return 0 if class_for_each_device() returned 1, -EPROBE_DEFER if
 223          * it returned 0, or error as returned by it.
 224          */
 225         error = class_for_each_device(power_supply_class, NULL, supply_node,
 226                                        __power_supply_find_supply_from_node);
 227
 228         return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
 229 }
 230
 231 static int power_supply_check_supplies(struct power_supply *psy)
 232 {
 233         struct device_node *np;
 234         int cnt = 0;
 235
 236         /* If there is already a list honor it */
 237         if (psy->supplied_from && psy->num_supplies > 0)
 238                 return 0;
 239
 240         /* No device node found, nothing to do */
 241         if (!psy->of_node)
 242                 return 0;
 243
 244         do {
 245                 int ret;
 246
 247                 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
 248                 if (!np)
 249                         break;
 250
 251                 ret = power_supply_find_supply_from_node(np);
 252                 of_node_put(np);
 253
 254                 if (ret) {
 255                         dev_dbg(&psy->dev, "Failed to find supply!\n");
 256                         return ret;
 257                 }
 258         } while (np);
 259
 260         /* Missing valid "power-supplies" entries */
 261         if (cnt == 1)
 262                 return 0;
 263
 264         /* All supplies found, allocate char ** array for filling */
 265         psy->supplied_from = devm_kzalloc(&psy->dev, sizeof(psy->supplied_from),
 266                                           GFP_KERNEL);
 267         if (!psy->supplied_from) {
 268                 dev_err(&psy->dev, "Couldn't allocate memory for supply list\n");
 269                 return -ENOMEM;
 270         }
 271
 272         *psy->supplied_from = devm_kzalloc(&psy->dev,
 273                                            sizeof(char *) * (cnt - 1),
 274                                            GFP_KERNEL);
 275         if (!*psy->supplied_from) {
 276                 dev_err(&psy->dev, "Couldn't allocate memory for supply list\n");
 277                 return -ENOMEM;
 278         }
 279
 280         return power_supply_populate_supplied_from(psy);
 281 }
 282 #else
 283 static inline int power_supply_check_supplies(struct power_supply *psy)
 284 {
 285         return 0;
 286 }
 287 #endif
 288
 289 static int __power_supply_am_i_supplied(struct device *dev, void *data)
 290 {
 291         union power_supply_propval ret = {0,};
 292         struct power_supply *psy = data;
 293         struct power_supply *epsy = dev_get_drvdata(dev);
 294
 295         if (__power_supply_is_supplied_by(epsy, psy))
 296                 if (!epsy->desc->get_property(epsy, POWER_SUPPLY_PROP_ONLINE,
 297                                         &ret))
 298                         return ret.intval;
 299
 300         return 0;
 301 }
 302
 303 int power_supply_am_i_supplied(struct power_supply *psy)
 304 {
 305         int error;
 306
 307         error = class_for_each_device(power_supply_class, NULL, psy,
 308                                       __power_supply_am_i_supplied);
 309
 310         dev_dbg(&psy->dev, "%s %d\n", __func__, error);
 311
 312         return error;
 313 }
 314 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
 315
 316 static int __power_supply_is_system_supplied(struct device *dev, void *data)
 317 {
 318         union power_supply_propval ret = {0,};
 319         struct power_supply *psy = dev_get_drvdata(dev);
 320         unsigned int *count = data;
 321
 322         (*count)++;
 323         if (psy->desc->type != POWER_SUPPLY_TYPE_BATTERY)
 324                 if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_ONLINE,
 325                                         &ret))
 326                         return ret.intval;
 327
 328         return 0;
 329 }
 330
 331 int power_supply_is_system_supplied(void)
 332 {
 333         int error;
 334         unsigned int count = 0;
 335
 336         error = class_for_each_device(power_supply_class, NULL, &count,
 337                                       __power_supply_is_system_supplied);
 338
 339         /*
 340          * If no power class device was found at all, most probably we are
 341          * running on a desktop system, so assume we are on mains power.
 342          */
 343         if (count == 0)
 344                 return 1;
 345
 346         return error;
 347 }
 348 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
 349
 350 int power_supply_set_battery_charged(struct power_supply *psy)
 351 {
 352         if (atomic_read(&psy->use_cnt) >= 0 &&
 353                         psy->desc->type == POWER_SUPPLY_TYPE_BATTERY &&
 354                         psy->desc->set_charged) {
 355                 psy->desc->set_charged(psy);
 356                 return 0;
 357         }
 358
 359         return -EINVAL;
 360 }
 361 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 362
 363 static int power_supply_match_device_by_name(struct device *dev, const void *data)
 364 {
 365         const char *name = data;
 366         struct power_supply *psy = dev_get_drvdata(dev);
 367
 368         return strcmp(psy->desc->name, name) == 0;
 369 }
 370
 371 /**
 372  * power_supply_get_by_name() - Search for a power supply and returns its ref
 373  * @name: Power supply name to fetch
 374  *
 375  * If power supply was found, it increases reference count for the
 376  * internal power supply's device. The user should power_supply_put()
 377  * after usage.
 378  *
 379  * Return: On success returns a reference to a power supply with
 380  * matching name equals to @name, a NULL otherwise.
 381  */
 382 struct power_supply *power_supply_get_by_name(const char *name)
 383 {
 384         struct power_supply *psy = NULL;
 385         struct device *dev = class_find_device(power_supply_class, NULL, name,
 386                                         power_supply_match_device_by_name);
 387
 388         if (dev) {
 389                 psy = dev_get_drvdata(dev);
 390                 atomic_inc(&psy->use_cnt);
 391         }
 392
 393         return psy;
 394 }
 395 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
 396
 397 /**
 398  * power_supply_put() - Drop reference obtained with power_supply_get_by_name
 399  * @psy: Reference to put
 400  *
 401  * The reference to power supply should be put before unregistering
 402  * the power supply.
 403  */
 404 void power_supply_put(struct power_supply *psy)
 405 {
 406         might_sleep();
 407
 408         atomic_dec(&psy->use_cnt);
 409         put_device(&psy->dev);
 410 }
 411 EXPORT_SYMBOL_GPL(power_supply_put);
 412
 413 #ifdef CONFIG_OF
 414 static int power_supply_match_device_node(struct device *dev, const void *data)
 415 {
 416         return dev->parent && dev->parent->of_node == data;
 417 }
 418
 419 /**
 420  * power_supply_get_by_phandle() - Search for a power supply and returns its ref
 421  * @np: Pointer to device node holding phandle property
 422  * @phandle_name: Name of property holding a power supply name
 423  *
 424  * If power supply was found, it increases reference count for the
 425  * internal power supply's device. The user should power_supply_put()
 426  * after usage.
 427  *
 428  * Return: On success returns a reference to a power supply with
 429  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 430  */
 431 struct power_supply *power_supply_get_by_phandle(struct device_node *np,
 432                                                         const char *property)
 433 {
 434         struct device_node *power_supply_np;
 435         struct power_supply *psy = NULL;
 436         struct device *dev;
 437
 438         power_supply_np = of_parse_phandle(np, property, 0);
 439         if (!power_supply_np)
 440                 return ERR_PTR(-ENODEV);
 441
 442         dev = class_find_device(power_supply_class, NULL, power_supply_np,
 443                                                 power_supply_match_device_node);
 444
 445         of_node_put(power_supply_np);
 446
 447         if (dev) {
 448                 psy = dev_get_drvdata(dev);
 449                 atomic_inc(&psy->use_cnt);
 450         }
 451
 452         return psy;
 453 }
 454 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
 455
 456 static void devm_power_supply_put(struct device *dev, void *res)
 457 {
 458         struct power_supply **psy = res;
 459
 460         power_supply_put(*psy);
 461 }
 462
 463 /**
 464  * devm_power_supply_get_by_phandle() - Resource managed version of
 465  *  power_supply_get_by_phandle()
 466  * @dev: Pointer to device holding phandle property
 467  * @phandle_name: Name of property holding a power supply phandle
 468  *
 469  * Return: On success returns a reference to a power supply with
 470  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 471  */
 472 struct power_supply *devm_power_supply_get_by_phandle(struct device *dev,
 473                                                       const char *property)
 474 {
 475         struct power_supply **ptr, *psy;
 476
 477         if (!dev->of_node)
 478                 return ERR_PTR(-ENODEV);
 479
 480         ptr = devres_alloc(devm_power_supply_put, sizeof(*ptr), GFP_KERNEL);
 481         if (!ptr)
 482                 return ERR_PTR(-ENOMEM);
 483
 484         psy = power_supply_get_by_phandle(dev->of_node, property);
 485         if (IS_ERR_OR_NULL(psy)) {
 486                 devres_free(ptr);
 487         } else {
 488                 *ptr = psy;
 489                 devres_add(dev, ptr);
 490         }
 491         return psy;
 492 }
 493 EXPORT_SYMBOL_GPL(devm_power_supply_get_by_phandle);
 494 #endif /* CONFIG_OF */
 495
 496 int power_supply_get_property(struct power_supply *psy,
 497                             enum power_supply_property psp,
 498                             union power_supply_propval *val)
 499 {
 500         if (atomic_read(&psy->use_cnt) <= 0) {
 501                 if (!psy->initialized)
 502                         return -EAGAIN;
 503                 return -ENODEV;
 504         }
 505
 506         return psy->desc->get_property(psy, psp, val);
 507 }
 508 EXPORT_SYMBOL_GPL(power_supply_get_property);
 509
 510 int power_supply_set_property(struct power_supply *psy,
 511                             enum power_supply_property psp,
 512                             const union power_supply_propval *val)
 513 {
 514         if (atomic_read(&psy->use_cnt) <= 0 || !psy->desc->set_property)
 515                 return -ENODEV;
 516
 517         return psy->desc->set_property(psy, psp, val);
 518 }
 519 EXPORT_SYMBOL_GPL(power_supply_set_property);
 520
 521 int power_supply_property_is_writeable(struct power_supply *psy,
 522                                         enum power_supply_property psp)
 523 {
 524         if (atomic_read(&psy->use_cnt) <= 0 ||
 525                         !psy->desc->property_is_writeable)
 526                 return -ENODEV;
 527
 528         return psy->desc->property_is_writeable(psy, psp);
 529 }
 530 EXPORT_SYMBOL_GPL(power_supply_property_is_writeable);
 531
 532 void power_supply_external_power_changed(struct power_supply *psy)
 533 {
 534         if (atomic_read(&psy->use_cnt) <= 0 ||
 535                         !psy->desc->external_power_changed)
 536                 return;
 537
 538         psy->desc->external_power_changed(psy);
 539 }
 540 EXPORT_SYMBOL_GPL(power_supply_external_power_changed);
 541
 542 int power_supply_powers(struct power_supply *psy, struct device *dev)
 543 {
 544         return sysfs_create_link(&psy->dev.kobj, &dev->kobj, "powers");
 545 }
 546 EXPORT_SYMBOL_GPL(power_supply_powers);
 547
 548 static void power_supply_dev_release(struct device *dev)
 549 {
 550         struct power_supply *psy = container_of(dev, struct power_supply, dev);
 551         pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 552         kfree(psy);
 553 }
 554
 555 int power_supply_reg_notifier(struct notifier_block *nb)
 556 {
 557         return atomic_notifier_chain_register(&power_supply_notifier, nb);
 558 }
 559 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
 560
 561 void power_supply_unreg_notifier(struct notifier_block *nb)
 562 {
 563         atomic_notifier_chain_unregister(&power_supply_notifier, nb);
 564 }
 565 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
 566
 567 #ifdef CONFIG_THERMAL
 568 static int power_supply_read_temp(struct thermal_zone_device *tzd,
 569                 int *temp)
 570 {
 571         struct power_supply *psy;
 572         union power_supply_propval val;
 573         int ret;
 574
 575         WARN_ON(tzd == NULL);
 576         psy = tzd->devdata;
 577         ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
 578         if (ret)
 579                 return ret;
 580
 581         /* Convert tenths of degree Celsius to milli degree Celsius. */
 582         *temp = val.intval * 100;
 583
 584         return ret;
 585 }
 586
 587 static struct thermal_zone_device_ops psy_tzd_ops = {
 588         .get_temp = power_supply_read_temp,
 589 };
 590
 591 static int psy_register_thermal(struct power_supply *psy)
 592 {
 593         int i;
 594
 595         if (psy->desc->no_thermal)
 596                 return 0;
 597
 598         /* Register battery zone device psy reports temperature */
 599         for (i = 0; i < psy->desc->num_properties; i++) {
 600                 if (psy->desc->properties[i] == POWER_SUPPLY_PROP_TEMP) {
 601                         psy->tzd = thermal_zone_device_register(psy->desc->name,
 602                                         0, 0, psy, &psy_tzd_ops, NULL, 0, 0);
 603                         return PTR_ERR_OR_ZERO(psy->tzd);
 604                 }
 605         }
 606         return 0;
 607 }
 608
 609 static void psy_unregister_thermal(struct power_supply *psy)
 610 {
 611         if (IS_ERR_OR_NULL(psy->tzd))
 612                 return;
 613         thermal_zone_device_unregister(psy->tzd);
 614 }
 615
 616 /* thermal cooling device callbacks */
 617 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
 618                                         unsigned long *state)
 619 {
 620         struct power_supply *psy;
 621         union power_supply_propval val;
 622         int ret;
 623
 624         psy = tcd->devdata;
 625         ret = power_supply_get_property(psy,
 626                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
 627         if (ret)
 628                 return ret;
 629
 630         *state = val.intval;
 631
 632         return ret;
 633 }
 634
 635 static int ps_get_cur_chrage_cntl_limit(struct thermal_cooling_device *tcd,
 636                                         unsigned long *state)
 637 {
 638         struct power_supply *psy;
 639         union power_supply_propval val;
 640         int ret;
 641
 642         psy = tcd->devdata;
 643         ret = power_supply_get_property(psy,
 644                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 645         if (ret)
 646                 return ret;
 647
 648         *state = val.intval;
 649
 650         return ret;
 651 }
 652
 653 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
 654                                         unsigned long state)
 655 {
 656         struct power_supply *psy;
 657         union power_supply_propval val;
 658         int ret;
 659
 660         psy = tcd->devdata;
 661         val.intval = state;
 662         ret = psy->desc->set_property(psy,
 663                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
 664
 665         return ret;
 666 }
 667
 668 static struct thermal_cooling_device_ops psy_tcd_ops = {
 669         .get_max_state = ps_get_max_charge_cntl_limit,
 670         .get_cur_state = ps_get_cur_chrage_cntl_limit,
 671         .set_cur_state = ps_set_cur_charge_cntl_limit,
 672 };
 673
 674 static int psy_register_cooler(struct power_supply *psy)
 675 {
 676         int i;
 677
 678         /* Register for cooling device if psy can control charging */
 679         for (i = 0; i < psy->desc->num_properties; i++) {
 680                 if (psy->desc->properties[i] ==
 681                                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
 682                         psy->tcd = thermal_cooling_device_register(
 683                                                         (char *)psy->desc->name,
 684                                                         psy, &psy_tcd_ops);
 685                         return PTR_ERR_OR_ZERO(psy->tcd);
 686                 }
 687         }
 688         return 0;
 689 }
 690
 691 static void psy_unregister_cooler(struct power_supply *psy)
 692 {
 693         if (IS_ERR_OR_NULL(psy->tcd))
 694                 return;
 695         thermal_cooling_device_unregister(psy->tcd);
 696 }
 697 #else
 698 static int psy_register_thermal(struct power_supply *psy)
 699 {
 700         return 0;
 701 }
 702
 703 static void psy_unregister_thermal(struct power_supply *psy)
 704 {
 705 }
 706
 707 static int psy_register_cooler(struct power_supply *psy)
 708 {
 709         return 0;
 710 }
 711
 712 static void psy_unregister_cooler(struct power_supply *psy)
 713 {
 714 }
 715 #endif
 716
 717 static struct power_supply *__must_check
 718 __power_supply_register(struct device *parent,
 719                                    const struct power_supply_desc *desc,
 720                                    const struct power_supply_config *cfg,
 721                                    bool ws)
 722 {
 723         struct device *dev;
 724         struct power_supply *psy;
 725         int rc;
 726
 727         if (!parent)
 728                 pr_warn("%s: Expected proper parent device for '%s'\n",
 729                         __func__, desc->name);
 730
 731         psy = kzalloc(sizeof(*psy), GFP_KERNEL);
 732         if (!psy)
 733                 return ERR_PTR(-ENOMEM);
 734
 735         dev = &psy->dev;
 736
 737         device_initialize(dev);
 738
 739         dev->class = power_supply_class;
 740         dev->type = &power_supply_dev_type;
 741         dev->parent = parent;
 742         dev->release = power_supply_dev_release;
 743         dev_set_drvdata(dev, psy);
 744         psy->desc = desc;
 745         if (cfg) {
 746                 psy->drv_data = cfg->drv_data;
 747                 psy->of_node = cfg->of_node;
 748                 psy->supplied_to = cfg->supplied_to;
 749                 psy->num_supplicants = cfg->num_supplicants;
 750         }
 751
 752         rc = dev_set_name(dev, "%s", desc->name);
 753         if (rc)
 754                 goto dev_set_name_failed;
 755
 756         INIT_WORK(&psy->changed_work, power_supply_changed_work);
 757         INIT_DELAYED_WORK(&psy->deferred_register_work,
 758                           power_supply_deferred_register_work);
 759
 760         rc = power_supply_check_supplies(psy);
 761         if (rc) {
 762                 dev_info(dev, "Not all required supplies found, defer probe\n");
 763                 goto check_supplies_failed;
 764         }
 765
 766         spin_lock_init(&psy->changed_lock);
 767         rc = device_add(dev);
 768         if (rc)
 769                 goto device_add_failed;
 770
 771         rc = device_init_wakeup(dev, ws);
 772         if (rc)
 773                 goto wakeup_init_failed;
 774
 775         rc = psy_register_thermal(psy);
 776         if (rc)
 777                 goto register_thermal_failed;
 778
 779         rc = psy_register_cooler(psy);
 780         if (rc)
 781                 goto register_cooler_failed;
 782
 783         rc = power_supply_create_triggers(psy);
 784         if (rc)
 785                 goto create_triggers_failed;
 786
 787         /*
 788          * Update use_cnt after any uevents (most notably from device_add()).
 789          * We are here still during driver's probe but
 790          * the power_supply_uevent() calls back driver's get_property
 791          * method so:
 792          * 1. Driver did not assigned the returned struct power_supply,
 793          * 2. Driver could not finish initialization (anything in its probe
 794          *    after calling power_supply_register()).
 795          */
 796         atomic_inc(&psy->use_cnt);
 797         psy->initialized = true;
 798
 799         queue_delayed_work(system_power_efficient_wq,
 800                            &psy->deferred_register_work,
 801                            POWER_SUPPLY_DEFERRED_REGISTER_TIME);
 802
 803         return psy;
 804
 805 create_triggers_failed:
 806         psy_unregister_cooler(psy);
 807 register_cooler_failed:
 808         psy_unregister_thermal(psy);
 809 register_thermal_failed:
 810         device_del(dev);
 811 wakeup_init_failed:
 812 device_add_failed:
 813 check_supplies_failed:
 814 dev_set_name_failed:
 815         put_device(dev);
 816         return ERR_PTR(rc);
 817 }
 818
 819 /**
 820  * power_supply_register() - Register new power supply
 821  * @parent:     Device to be a parent of power supply's device, usually
 822  *              the device which probe function calls this
 823  * @desc:       Description of power supply, must be valid through whole
 824  *              lifetime of this power supply
 825  * @cfg:        Run-time specific configuration accessed during registering,
 826  *              may be NULL
 827  *
 828  * Return: A pointer to newly allocated power_supply on success
 829  * or ERR_PTR otherwise.
 830  * Use power_supply_unregister() on returned power_supply pointer to release
 831  * resources.
 832  */
 833 struct power_supply *__must_check power_supply_register(struct device *parent,
 834                 const struct power_supply_desc *desc,
 835                 const struct power_supply_config *cfg)
 836 {
 837         return __power_supply_register(parent, desc, cfg, true);
 838 }
 839 EXPORT_SYMBOL_GPL(power_supply_register);
 840
 841 /**
 842  * power_supply_register_no_ws() - Register new non-waking-source power supply
 843  * @parent:     Device to be a parent of power supply's device, usually
 844  *              the device which probe function calls this
 845  * @desc:       Description of power supply, must be valid through whole
 846  *              lifetime of this power supply
 847  * @cfg:        Run-time specific configuration accessed during registering,
 848  *              may be NULL
 849  *
 850  * Return: A pointer to newly allocated power_supply on success
 851  * or ERR_PTR otherwise.
 852  * Use power_supply_unregister() on returned power_supply pointer to release
 853  * resources.
 854  */
 855 struct power_supply *__must_check
 856 power_supply_register_no_ws(struct device *parent,
 857                 const struct power_supply_desc *desc,
 858                 const struct power_supply_config *cfg)
 859 {
 860         return __power_supply_register(parent, desc, cfg, false);
 861 }
 862 EXPORT_SYMBOL_GPL(power_supply_register_no_ws);
 863
 864 static void devm_power_supply_release(struct device *dev, void *res)
 865 {
 866         struct power_supply **psy = res;
 867
 868         power_supply_unregister(*psy);
 869 }
 870
 871 /**
 872  * devm_power_supply_register() - Register managed power supply
 873  * @parent:     Device to be a parent of power supply's device, usually
 874  *              the device which probe function calls this
 875  * @desc:       Description of power supply, must be valid through whole
 876  *              lifetime of this power supply
 877  * @cfg:        Run-time specific configuration accessed during registering,
 878  *              may be NULL
 879  *
 880  * Return: A pointer to newly allocated power_supply on success
 881  * or ERR_PTR otherwise.
 882  * The returned power_supply pointer will be automatically unregistered
 883  * on driver detach.
 884  */
 885 struct power_supply *__must_check
 886 devm_power_supply_register(struct device *parent,
 887                 const struct power_supply_desc *desc,
 888                 const struct power_supply_config *cfg)
 889 {
 890         struct power_supply **ptr, *psy;
 891
 892         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
 893
 894         if (!ptr)
 895                 return ERR_PTR(-ENOMEM);
 896         psy = __power_supply_register(parent, desc, cfg, true);
 897         if (IS_ERR(psy)) {
 898                 devres_free(ptr);
 899         } else {
 900                 *ptr = psy;
 901                 devres_add(parent, ptr);
 902         }
 903         return psy;
 904 }
 905 EXPORT_SYMBOL_GPL(devm_power_supply_register);
 906
 907 /**
 908  * devm_power_supply_register_no_ws() - Register managed non-waking-source power supply
 909  * @parent:     Device to be a parent of power supply's device, usually
 910  *              the device which probe function calls this
 911  * @desc:       Description of power supply, must be valid through whole
 912  *              lifetime of this power supply
 913  * @cfg:        Run-time specific configuration accessed during registering,
 914  *              may be NULL
 915  *
 916  * Return: A pointer to newly allocated power_supply on success
 917  * or ERR_PTR otherwise.
 918  * The returned power_supply pointer will be automatically unregistered
 919  * on driver detach.
 920  */
 921 struct power_supply *__must_check
 922 devm_power_supply_register_no_ws(struct device *parent,
 923                 const struct power_supply_desc *desc,
 924                 const struct power_supply_config *cfg)
 925 {
 926         struct power_supply **ptr, *psy;
 927
 928         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
 929
 930         if (!ptr)
 931                 return ERR_PTR(-ENOMEM);
 932         psy = __power_supply_register(parent, desc, cfg, false);
 933         if (IS_ERR(psy)) {
 934                 devres_free(ptr);
 935         } else {
 936                 *ptr = psy;
 937                 devres_add(parent, ptr);
 938         }
 939         return psy;
 940 }
 941 EXPORT_SYMBOL_GPL(devm_power_supply_register_no_ws);
 942
 943 /**
 944  * power_supply_unregister() - Remove this power supply from system
 945  * @psy:        Pointer to power supply to unregister
 946  *
 947  * Remove this power supply from the system. The resources of power supply
 948  * will be freed here or on last power_supply_put() call.
 949  */
 950 void power_supply_unregister(struct power_supply *psy)
 951 {
 952         WARN_ON(atomic_dec_return(&psy->use_cnt));
 953         psy->removing = true;
 954         cancel_work_sync(&psy->changed_work);
 955         cancel_delayed_work_sync(&psy->deferred_register_work);
 956         sysfs_remove_link(&psy->dev.kobj, "powers");
 957         power_supply_remove_triggers(psy);
 958         psy_unregister_cooler(psy);
 959         psy_unregister_thermal(psy);
 960         device_init_wakeup(&psy->dev, false);
 961         device_unregister(&psy->dev);
 962 }
 963 EXPORT_SYMBOL_GPL(power_supply_unregister);
 964
 965 void *power_supply_get_drvdata(struct power_supply *psy)
 966 {
 967         return psy->drv_data;
 968 }
 969 EXPORT_SYMBOL_GPL(power_supply_get_drvdata);
 970
 971 static int __init power_supply_class_init(void)
 972 {
 973         power_supply_class = class_create(THIS_MODULE, "power_supply");
 974
 975         if (IS_ERR(power_supply_class))
 976                 return PTR_ERR(power_supply_class);
 977
 978         power_supply_class->dev_uevent = power_supply_uevent;
 979         power_supply_init_attrs(&power_supply_dev_type);
 980
 981         return 0;
 982 }
 983
 984 static void __exit power_supply_class_exit(void)
 985 {
 986         class_destroy(power_supply_class);
 987 }
 988
 989 subsys_initcall(power_supply_class_init);
 990 module_exit(power_supply_class_exit);
 991
 992 MODULE_DESCRIPTION("Universal power supply monitor class");
 993 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
 994               "Szabolcs Gyurko, "
 995               "Anton Vorontsov <cbou@mail.ru>");
 996 MODULE_LICENSE("GPL");