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