drivers/power/supply/power_supply_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Universal power supply monitor class
   4  *
   5  *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
   6  *  Copyright © 2004  Szabolcs Gyurko
   7  *  Copyright © 2003  Ian Molton <spyro@f2s.com>
   8  *
   9  *  Modified: 2004, Oct     Szabolcs Gyurko
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/init.h>
  15 #include <linux/slab.h>
  16 #include <linux/delay.h>
  17 #include <linux/device.h>
  18 #include <linux/notifier.h>
  19 #include <linux/err.h>
  20 #include <linux/of.h>
  21 #include <linux/power_supply.h>
  22 #include <linux/property.h>
  23 #include <linux/thermal.h>
  24 #include "power_supply.h"
  25
  26 /* exported for the APM Power driver, APM emulation */
  27 struct class *power_supply_class;
  28 EXPORT_SYMBOL_GPL(power_supply_class);
  29
  30 ATOMIC_NOTIFIER_HEAD(power_supply_notifier);
  31 EXPORT_SYMBOL_GPL(power_supply_notifier);
  32
  33 static struct device_type power_supply_dev_type;
  34
  35 #define POWER_SUPPLY_DEFERRED_REGISTER_TIME     msecs_to_jiffies(10)
  36
  37 static bool __power_supply_is_supplied_by(struct power_supply *supplier,
  38                                          struct power_supply *supply)
  39 {
  40         int i;
  41
  42         if (!supply->supplied_from && !supplier->supplied_to)
  43                 return false;
  44
  45         /* Support both supplied_to and supplied_from modes */
  46         if (supply->supplied_from) {
  47                 if (!supplier->desc->name)
  48                         return false;
  49                 for (i = 0; i < supply->num_supplies; i++)
  50                         if (!strcmp(supplier->desc->name, supply->supplied_from[i]))
  51                                 return true;
  52         } else {
  53                 if (!supply->desc->name)
  54                         return false;
  55                 for (i = 0; i < supplier->num_supplicants; i++)
  56                         if (!strcmp(supplier->supplied_to[i], supply->desc->name))
  57                                 return true;
  58         }
  59
  60         return false;
  61 }
  62
  63 static int __power_supply_changed_work(struct device *dev, void *data)
  64 {
  65         struct power_supply *psy = data;
  66         struct power_supply *pst = dev_get_drvdata(dev);
  67
  68         if (__power_supply_is_supplied_by(psy, pst)) {
  69                 if (pst->desc->external_power_changed)
  70                         pst->desc->external_power_changed(pst);
  71         }
  72
  73         return 0;
  74 }
  75
  76 static void power_supply_changed_work(struct work_struct *work)
  77 {
  78         unsigned long flags;
  79         struct power_supply *psy = container_of(work, struct power_supply,
  80                                                 changed_work);
  81
  82         dev_dbg(&psy->dev, "%s\n", __func__);
  83
  84         spin_lock_irqsave(&psy->changed_lock, flags);
  85         /*
  86          * Check 'changed' here to avoid issues due to race between
  87          * power_supply_changed() and this routine. In worst case
  88          * power_supply_changed() can be called again just before we take above
  89          * lock. During the first call of this routine we will mark 'changed' as
  90          * false and it will stay false for the next call as well.
  91          */
  92         if (likely(psy->changed)) {
  93                 psy->changed = false;
  94                 spin_unlock_irqrestore(&psy->changed_lock, flags);
  95                 class_for_each_device(power_supply_class, NULL, psy,
  96                                       __power_supply_changed_work);
  97                 power_supply_update_leds(psy);
  98                 atomic_notifier_call_chain(&power_supply_notifier,
  99                                 PSY_EVENT_PROP_CHANGED, psy);
 100                 kobject_uevent(&psy->dev.kobj, KOBJ_CHANGE);
 101                 spin_lock_irqsave(&psy->changed_lock, flags);
 102         }
 103
 104         /*
 105          * Hold the wakeup_source until all events are processed.
 106          * power_supply_changed() might have called again and have set 'changed'
 107          * to true.
 108          */
 109         if (likely(!psy->changed))
 110                 pm_relax(&psy->dev);
 111         spin_unlock_irqrestore(&psy->changed_lock, flags);
 112 }
 113
 114 void power_supply_changed(struct power_supply *psy)
 115 {
 116         unsigned long flags;
 117
 118         dev_dbg(&psy->dev, "%s\n", __func__);
 119
 120         spin_lock_irqsave(&psy->changed_lock, flags);
 121         psy->changed = true;
 122         pm_stay_awake(&psy->dev);
 123         spin_unlock_irqrestore(&psy->changed_lock, flags);
 124         schedule_work(&psy->changed_work);
 125 }
 126 EXPORT_SYMBOL_GPL(power_supply_changed);
 127
 128 /*
 129  * Notify that power supply was registered after parent finished the probing.
 130  *
 131  * Often power supply is registered from driver's probe function. However
 132  * calling power_supply_changed() directly from power_supply_register()
 133  * would lead to execution of get_property() function provided by the driver
 134  * too early - before the probe ends.
 135  *
 136  * Avoid that by waiting on parent's mutex.
 137  */
 138 static void power_supply_deferred_register_work(struct work_struct *work)
 139 {
 140         struct power_supply *psy = container_of(work, struct power_supply,
 141                                                 deferred_register_work.work);
 142
 143         if (psy->dev.parent) {
 144                 while (!mutex_trylock(&psy->dev.parent->mutex)) {
 145                         if (psy->removing)
 146                                 return;
 147                         msleep(10);
 148                 }
 149         }
 150
 151         power_supply_changed(psy);
 152
 153         if (psy->dev.parent)
 154                 mutex_unlock(&psy->dev.parent->mutex);
 155 }
 156
 157 #ifdef CONFIG_OF
 158 static int __power_supply_populate_supplied_from(struct device *dev,
 159                                                  void *data)
 160 {
 161         struct power_supply *psy = data;
 162         struct power_supply *epsy = dev_get_drvdata(dev);
 163         struct device_node *np;
 164         int i = 0;
 165
 166         do {
 167                 np = of_parse_phandle(psy->of_node, "power-supplies", i++);
 168                 if (!np)
 169                         break;
 170
 171                 if (np == epsy->of_node) {
 172                         dev_info(&psy->dev, "%s: Found supply : %s\n",
 173                                 psy->desc->name, epsy->desc->name);
 174                         psy->supplied_from[i-1] = (char *)epsy->desc->name;
 175                         psy->num_supplies++;
 176                         of_node_put(np);
 177                         break;
 178                 }
 179                 of_node_put(np);
 180         } while (np);
 181
 182         return 0;
 183 }
 184
 185 static int power_supply_populate_supplied_from(struct power_supply *psy)
 186 {
 187         int error;
 188
 189         error = class_for_each_device(power_supply_class, NULL, psy,
 190                                       __power_supply_populate_supplied_from);
 191
 192         dev_dbg(&psy->dev, "%s %d\n", __func__, error);
 193
 194         return error;
 195 }
 196
 197 static int  __power_supply_find_supply_from_node(struct device *dev,
 198                                                  void *data)
 199 {
 200         struct device_node *np = data;
 201         struct power_supply *epsy = dev_get_drvdata(dev);
 202
 203         /* returning non-zero breaks out of class_for_each_device loop */
 204         if (epsy->of_node == np)
 205                 return 1;
 206
 207         return 0;
 208 }
 209
 210 static int power_supply_find_supply_from_node(struct device_node *supply_node)
 211 {
 212         int error;
 213
 214         /*
 215          * class_for_each_device() either returns its own errors or values
 216          * returned by __power_supply_find_supply_from_node().
 217          *
 218          * __power_supply_find_supply_from_node() will return 0 (no match)
 219          * or 1 (match).
 220          *
 221          * We return 0 if class_for_each_device() returned 1, -EPROBE_DEFER if
 222          * it returned 0, or error as returned by it.
 223          */
 224         error = class_for_each_device(power_supply_class, NULL, supply_node,
 225                                        __power_supply_find_supply_from_node);
 226
 227         return error ? (error == 1 ? 0 : error) : -EPROBE_DEFER;
 228 }
 229
 230 static int power_supply_check_supplies(struct power_supply *psy)
 231 {
 232         struct device_node *np;
 233         int cnt = 0;
 234
 235         /* If there is already a list honor it */
 236         if (psy->supplied_from && psy->num_supplies > 0)
 237                 return 0;
 238
 239         /* No device node found, nothing to do */
 240         if (!psy->of_node)
 241                 return 0;
 242
 243         do {
 244                 int ret;
 245
 246                 np = of_parse_phandle(psy->of_node, "power-supplies", cnt++);
 247                 if (!np)
 248                         break;
 249
 250                 ret = power_supply_find_supply_from_node(np);
 251                 of_node_put(np);
 252
 253                 if (ret) {
 254                         dev_dbg(&psy->dev, "Failed to find supply!\n");
 255                         return ret;
 256                 }
 257         } while (np);
 258
 259         /* Missing valid "power-supplies" entries */
 260         if (cnt == 1)
 261                 return 0;
 262
 263         /* All supplies found, allocate char ** array for filling */
 264         psy->supplied_from = devm_kzalloc(&psy->dev, sizeof(psy->supplied_from),
 265                                           GFP_KERNEL);
 266         if (!psy->supplied_from)
 267                 return -ENOMEM;
 268
 269         *psy->supplied_from = devm_kcalloc(&psy->dev,
 270                                            cnt - 1, sizeof(char *),
 271                                            GFP_KERNEL);
 272         if (!*psy->supplied_from)
 273                 return -ENOMEM;
 274
 275         return power_supply_populate_supplied_from(psy);
 276 }
 277 #else
 278 static int power_supply_check_supplies(struct power_supply *psy)
 279 {
 280         int nval, ret;
 281
 282         if (!psy->dev.parent)
 283                 return 0;
 284
 285         nval = device_property_read_string_array(psy->dev.parent,
 286                                                  "supplied-from", NULL, 0);
 287         if (nval <= 0)
 288                 return 0;
 289
 290         psy->supplied_from = devm_kmalloc_array(&psy->dev, nval,
 291                                                 sizeof(char *), GFP_KERNEL);
 292         if (!psy->supplied_from)
 293                 return -ENOMEM;
 294
 295         ret = device_property_read_string_array(psy->dev.parent,
 296                 "supplied-from", (const char **)psy->supplied_from, nval);
 297         if (ret < 0)
 298                 return ret;
 299
 300         psy->num_supplies = nval;
 301
 302         return 0;
 303 }
 304 #endif
 305
 306 struct psy_am_i_supplied_data {
 307         struct power_supply *psy;
 308         unsigned int count;
 309 };
 310
 311 static int __power_supply_am_i_supplied(struct device *dev, void *_data)
 312 {
 313         union power_supply_propval ret = {0,};
 314         struct power_supply *epsy = dev_get_drvdata(dev);
 315         struct psy_am_i_supplied_data *data = _data;
 316
 317         if (__power_supply_is_supplied_by(epsy, data->psy)) {
 318                 data->count++;
 319                 if (!epsy->desc->get_property(epsy, POWER_SUPPLY_PROP_ONLINE,
 320                                         &ret))
 321                         return ret.intval;
 322         }
 323
 324         return 0;
 325 }
 326
 327 int power_supply_am_i_supplied(struct power_supply *psy)
 328 {
 329         struct psy_am_i_supplied_data data = { psy, 0 };
 330         int error;
 331
 332         error = class_for_each_device(power_supply_class, NULL, &data,
 333                                       __power_supply_am_i_supplied);
 334
 335         dev_dbg(&psy->dev, "%s count %u err %d\n", __func__, data.count, error);
 336
 337         if (data.count == 0)
 338                 return -ENODEV;
 339
 340         return error;
 341 }
 342 EXPORT_SYMBOL_GPL(power_supply_am_i_supplied);
 343
 344 static int __power_supply_is_system_supplied(struct device *dev, void *data)
 345 {
 346         union power_supply_propval ret = {0,};
 347         struct power_supply *psy = dev_get_drvdata(dev);
 348         unsigned int *count = data;
 349
 350         if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_SCOPE, &ret))
 351                 if (ret.intval == POWER_SUPPLY_SCOPE_DEVICE)
 352                         return 0;
 353
 354         (*count)++;
 355         if (psy->desc->type != POWER_SUPPLY_TYPE_BATTERY)
 356                 if (!psy->desc->get_property(psy, POWER_SUPPLY_PROP_ONLINE,
 357                                         &ret))
 358                         return ret.intval;
 359
 360         return 0;
 361 }
 362
 363 int power_supply_is_system_supplied(void)
 364 {
 365         int error;
 366         unsigned int count = 0;
 367
 368         error = class_for_each_device(power_supply_class, NULL, &count,
 369                                       __power_supply_is_system_supplied);
 370
 371         /*
 372          * If no system scope power class device was found at all, most probably we
 373          * are running on a desktop system, so assume we are on mains power.
 374          */
 375         if (count == 0)
 376                 return 1;
 377
 378         return error;
 379 }
 380 EXPORT_SYMBOL_GPL(power_supply_is_system_supplied);
 381
 382 struct psy_get_supplier_prop_data {
 383         struct power_supply *psy;
 384         enum power_supply_property psp;
 385         union power_supply_propval *val;
 386 };
 387
 388 static int __power_supply_get_supplier_property(struct device *dev, void *_data)
 389 {
 390         struct power_supply *epsy = dev_get_drvdata(dev);
 391         struct psy_get_supplier_prop_data *data = _data;
 392
 393         if (__power_supply_is_supplied_by(epsy, data->psy))
 394                 if (!epsy->desc->get_property(epsy, data->psp, data->val))
 395                         return 1; /* Success */
 396
 397         return 0; /* Continue iterating */
 398 }
 399
 400 int power_supply_get_property_from_supplier(struct power_supply *psy,
 401                                             enum power_supply_property psp,
 402                                             union power_supply_propval *val)
 403 {
 404         struct psy_get_supplier_prop_data data = {
 405                 .psy = psy,
 406                 .psp = psp,
 407                 .val = val,
 408         };
 409         int ret;
 410
 411         /*
 412          * This function is not intended for use with a supply with multiple
 413          * suppliers, we simply pick the first supply to report the psp.
 414          */
 415         ret = class_for_each_device(power_supply_class, NULL, &data,
 416                                     __power_supply_get_supplier_property);
 417         if (ret < 0)
 418                 return ret;
 419         if (ret == 0)
 420                 return -ENODEV;
 421
 422         return 0;
 423 }
 424 EXPORT_SYMBOL_GPL(power_supply_get_property_from_supplier);
 425
 426 int power_supply_set_battery_charged(struct power_supply *psy)
 427 {
 428         if (atomic_read(&psy->use_cnt) >= 0 &&
 429                         psy->desc->type == POWER_SUPPLY_TYPE_BATTERY &&
 430                         psy->desc->set_charged) {
 431                 psy->desc->set_charged(psy);
 432                 return 0;
 433         }
 434
 435         return -EINVAL;
 436 }
 437 EXPORT_SYMBOL_GPL(power_supply_set_battery_charged);
 438
 439 static int power_supply_match_device_by_name(struct device *dev, const void *data)
 440 {
 441         const char *name = data;
 442         struct power_supply *psy = dev_get_drvdata(dev);
 443
 444         return strcmp(psy->desc->name, name) == 0;
 445 }
 446
 447 /**
 448  * power_supply_get_by_name() - Search for a power supply and returns its ref
 449  * @name: Power supply name to fetch
 450  *
 451  * If power supply was found, it increases reference count for the
 452  * internal power supply's device. The user should power_supply_put()
 453  * after usage.
 454  *
 455  * Return: On success returns a reference to a power supply with
 456  * matching name equals to @name, a NULL otherwise.
 457  */
 458 struct power_supply *power_supply_get_by_name(const char *name)
 459 {
 460         struct power_supply *psy = NULL;
 461         struct device *dev = class_find_device(power_supply_class, NULL, name,
 462                                         power_supply_match_device_by_name);
 463
 464         if (dev) {
 465                 psy = dev_get_drvdata(dev);
 466                 atomic_inc(&psy->use_cnt);
 467         }
 468
 469         return psy;
 470 }
 471 EXPORT_SYMBOL_GPL(power_supply_get_by_name);
 472
 473 /**
 474  * power_supply_put() - Drop reference obtained with power_supply_get_by_name
 475  * @psy: Reference to put
 476  *
 477  * The reference to power supply should be put before unregistering
 478  * the power supply.
 479  */
 480 void power_supply_put(struct power_supply *psy)
 481 {
 482         might_sleep();
 483
 484         atomic_dec(&psy->use_cnt);
 485         put_device(&psy->dev);
 486 }
 487 EXPORT_SYMBOL_GPL(power_supply_put);
 488
 489 #ifdef CONFIG_OF
 490 static int power_supply_match_device_node(struct device *dev, const void *data)
 491 {
 492         return dev->parent && dev->parent->of_node == data;
 493 }
 494
 495 /**
 496  * power_supply_get_by_phandle() - Search for a power supply and returns its ref
 497  * @np: Pointer to device node holding phandle property
 498  * @property: Name of property holding a power supply name
 499  *
 500  * If power supply was found, it increases reference count for the
 501  * internal power supply's device. The user should power_supply_put()
 502  * after usage.
 503  *
 504  * Return: On success returns a reference to a power supply with
 505  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 506  */
 507 struct power_supply *power_supply_get_by_phandle(struct device_node *np,
 508                                                         const char *property)
 509 {
 510         struct device_node *power_supply_np;
 511         struct power_supply *psy = NULL;
 512         struct device *dev;
 513
 514         power_supply_np = of_parse_phandle(np, property, 0);
 515         if (!power_supply_np)
 516                 return ERR_PTR(-ENODEV);
 517
 518         dev = class_find_device(power_supply_class, NULL, power_supply_np,
 519                                                 power_supply_match_device_node);
 520
 521         of_node_put(power_supply_np);
 522
 523         if (dev) {
 524                 psy = dev_get_drvdata(dev);
 525                 atomic_inc(&psy->use_cnt);
 526         }
 527
 528         return psy;
 529 }
 530 EXPORT_SYMBOL_GPL(power_supply_get_by_phandle);
 531
 532 static void devm_power_supply_put(struct device *dev, void *res)
 533 {
 534         struct power_supply **psy = res;
 535
 536         power_supply_put(*psy);
 537 }
 538
 539 /**
 540  * devm_power_supply_get_by_phandle() - Resource managed version of
 541  *  power_supply_get_by_phandle()
 542  * @dev: Pointer to device holding phandle property
 543  * @property: Name of property holding a power supply phandle
 544  *
 545  * Return: On success returns a reference to a power supply with
 546  * matching name equals to value under @property, NULL or ERR_PTR otherwise.
 547  */
 548 struct power_supply *devm_power_supply_get_by_phandle(struct device *dev,
 549                                                       const char *property)
 550 {
 551         struct power_supply **ptr, *psy;
 552
 553         if (!dev->of_node)
 554                 return ERR_PTR(-ENODEV);
 555
 556         ptr = devres_alloc(devm_power_supply_put, sizeof(*ptr), GFP_KERNEL);
 557         if (!ptr)
 558                 return ERR_PTR(-ENOMEM);
 559
 560         psy = power_supply_get_by_phandle(dev->of_node, property);
 561         if (IS_ERR_OR_NULL(psy)) {
 562                 devres_free(ptr);
 563         } else {
 564                 *ptr = psy;
 565                 devres_add(dev, ptr);
 566         }
 567         return psy;
 568 }
 569 EXPORT_SYMBOL_GPL(devm_power_supply_get_by_phandle);
 570 #endif /* CONFIG_OF */
 571
 572 int power_supply_get_battery_info(struct power_supply *psy,
 573                                   struct power_supply_battery_info *info)
 574 {
 575         struct power_supply_resistance_temp_table *resist_table;
 576         struct device_node *battery_np;
 577         const char *value;
 578         int err, len, index;
 579         const __be32 *list;
 580
 581         info->energy_full_design_uwh         = -EINVAL;
 582         info->charge_full_design_uah         = -EINVAL;
 583         info->voltage_min_design_uv          = -EINVAL;
 584         info->voltage_max_design_uv          = -EINVAL;
 585         info->precharge_current_ua           = -EINVAL;
 586         info->charge_term_current_ua         = -EINVAL;
 587         info->constant_charge_current_max_ua = -EINVAL;
 588         info->constant_charge_voltage_max_uv = -EINVAL;
 589         info->temp_ambient_alert_min         = INT_MIN;
 590         info->temp_ambient_alert_max         = INT_MAX;
 591         info->temp_alert_min                 = INT_MIN;
 592         info->temp_alert_max                 = INT_MAX;
 593         info->temp_min                       = INT_MIN;
 594         info->temp_max                       = INT_MAX;
 595         info->factory_internal_resistance_uohm  = -EINVAL;
 596         info->resist_table = NULL;
 597
 598         for (index = 0; index < POWER_SUPPLY_OCV_TEMP_MAX; index++) {
 599                 info->ocv_table[index]       = NULL;
 600                 info->ocv_temp[index]        = -EINVAL;
 601                 info->ocv_table_size[index]  = -EINVAL;
 602         }
 603
 604         if (!psy->of_node) {
 605                 dev_warn(&psy->dev, "%s currently only supports devicetree\n",
 606                          __func__);
 607                 return -ENXIO;
 608         }
 609
 610         battery_np = of_parse_phandle(psy->of_node, "monitored-battery", 0);
 611         if (!battery_np)
 612                 return -ENODEV;
 613
 614         err = of_property_read_string(battery_np, "compatible", &value);
 615         if (err)
 616                 goto out_put_node;
 617
 618         if (strcmp("simple-battery", value)) {
 619                 err = -ENODEV;
 620                 goto out_put_node;
 621         }
 622
 623         /* The property and field names below must correspond to elements
 624          * in enum power_supply_property. For reasoning, see
 625          * Documentation/power/power_supply_class.rst.
 626          */
 627
 628         of_property_read_u32(battery_np, "energy-full-design-microwatt-hours",
 629                              &info->energy_full_design_uwh);
 630         of_property_read_u32(battery_np, "charge-full-design-microamp-hours",
 631                              &info->charge_full_design_uah);
 632         of_property_read_u32(battery_np, "voltage-min-design-microvolt",
 633                              &info->voltage_min_design_uv);
 634         of_property_read_u32(battery_np, "voltage-max-design-microvolt",
 635                              &info->voltage_max_design_uv);
 636         of_property_read_u32(battery_np, "trickle-charge-current-microamp",
 637                              &info->tricklecharge_current_ua);
 638         of_property_read_u32(battery_np, "precharge-current-microamp",
 639                              &info->precharge_current_ua);
 640         of_property_read_u32(battery_np, "precharge-upper-limit-microvolt",
 641                              &info->precharge_voltage_max_uv);
 642         of_property_read_u32(battery_np, "charge-term-current-microamp",
 643                              &info->charge_term_current_ua);
 644         of_property_read_u32(battery_np, "re-charge-voltage-microvolt",
 645                              &info->charge_restart_voltage_uv);
 646         of_property_read_u32(battery_np, "over-voltage-threshold-microvolt",
 647                              &info->overvoltage_limit_uv);
 648         of_property_read_u32(battery_np, "constant-charge-current-max-microamp",
 649                              &info->constant_charge_current_max_ua);
 650         of_property_read_u32(battery_np, "constant-charge-voltage-max-microvolt",
 651                              &info->constant_charge_voltage_max_uv);
 652         of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms",
 653                              &info->factory_internal_resistance_uohm);
 654
 655         of_property_read_u32_index(battery_np, "ambient-celsius",
 656                                    0, &info->temp_ambient_alert_min);
 657         of_property_read_u32_index(battery_np, "ambient-celsius",
 658                                    1, &info->temp_ambient_alert_max);
 659         of_property_read_u32_index(battery_np, "alert-celsius",
 660                                    0, &info->temp_alert_min);
 661         of_property_read_u32_index(battery_np, "alert-celsius",
 662                                    1, &info->temp_alert_max);
 663         of_property_read_u32_index(battery_np, "operating-range-celsius",
 664                                    0, &info->temp_min);
 665         of_property_read_u32_index(battery_np, "operating-range-celsius",
 666                                    1, &info->temp_max);
 667
 668         len = of_property_count_u32_elems(battery_np, "ocv-capacity-celsius");
 669         if (len < 0 && len != -EINVAL) {
 670                 err = len;
 671                 goto out_put_node;
 672         } else if (len > POWER_SUPPLY_OCV_TEMP_MAX) {
 673                 dev_err(&psy->dev, "Too many temperature values\n");
 674                 err = -EINVAL;
 675                 goto out_put_node;
 676         } else if (len > 0) {
 677                 of_property_read_u32_array(battery_np, "ocv-capacity-celsius",
 678                                            info->ocv_temp, len);
 679         }
 680
 681         for (index = 0; index < len; index++) {
 682                 struct power_supply_battery_ocv_table *table;
 683                 char *propname;
 684                 int i, tab_len, size;
 685
 686                 propname = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d", index);
 687                 if (!propname) {
 688                         power_supply_put_battery_info(psy, info);
 689                         err = -ENOMEM;
 690                         goto out_put_node;
 691                 }
 692                 list = of_get_property(battery_np, propname, &size);
 693                 if (!list || !size) {
 694                         dev_err(&psy->dev, "failed to get %s\n", propname);
 695                         kfree(propname);
 696                         power_supply_put_battery_info(psy, info);
 697                         err = -EINVAL;
 698                         goto out_put_node;
 699                 }
 700
 701                 kfree(propname);
 702                 tab_len = size / (2 * sizeof(__be32));
 703                 info->ocv_table_size[index] = tab_len;
 704
 705                 table = info->ocv_table[index] =
 706                         devm_kcalloc(&psy->dev, tab_len, sizeof(*table), GFP_KERNEL);
 707                 if (!info->ocv_table[index]) {
 708                         power_supply_put_battery_info(psy, info);
 709                         err = -ENOMEM;
 710                         goto out_put_node;
 711                 }
 712
 713                 for (i = 0; i < tab_len; i++) {
 714                         table[i].ocv = be32_to_cpu(*list);
 715                         list++;
 716                         table[i].capacity = be32_to_cpu(*list);
 717                         list++;
 718                 }
 719         }
 720
 721         list = of_get_property(battery_np, "resistance-temp-table", &len);
 722         if (!list || !len)
 723                 goto out_put_node;
 724
 725         info->resist_table_size = len / (2 * sizeof(__be32));
 726         resist_table = info->resist_table = devm_kcalloc(&psy->dev,
 727                                                          info->resist_table_size,
 728                                                          sizeof(*resist_table),
 729                                                          GFP_KERNEL);
 730         if (!info->resist_table) {
 731                 power_supply_put_battery_info(psy, info);
 732                 err = -ENOMEM;
 733                 goto out_put_node;
 734         }
 735
 736         for (index = 0; index < info->resist_table_size; index++) {
 737                 resist_table[index].temp = be32_to_cpu(*list++);
 738                 resist_table[index].resistance = be32_to_cpu(*list++);
 739         }
 740
 741 out_put_node:
 742         of_node_put(battery_np);
 743         return err;
 744 }
 745 EXPORT_SYMBOL_GPL(power_supply_get_battery_info);
 746
 747 void power_supply_put_battery_info(struct power_supply *psy,
 748                                    struct power_supply_battery_info *info)
 749 {
 750         int i;
 751
 752         for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
 753                 if (info->ocv_table[i])
 754                         devm_kfree(&psy->dev, info->ocv_table[i]);
 755         }
 756
 757         if (info->resist_table)
 758                 devm_kfree(&psy->dev, info->resist_table);
 759 }
 760 EXPORT_SYMBOL_GPL(power_supply_put_battery_info);
 761
 762 /**
 763  * power_supply_temp2resist_simple() - find the battery internal resistance
 764  * percent
 765  * @table: Pointer to battery resistance temperature table
 766  * @table_len: The table length
 767  * @temp: Current temperature
 768  *
 769  * This helper function is used to look up battery internal resistance percent
 770  * according to current temperature value from the resistance temperature table,
 771  * and the table must be ordered descending. Then the actual battery internal
 772  * resistance = the ideal battery internal resistance * percent / 100.
 773  *
 774  * Return: the battery internal resistance percent
 775  */
 776 int power_supply_temp2resist_simple(struct power_supply_resistance_temp_table *table,
 777                                     int table_len, int temp)
 778 {
 779         int i, resist;
 780
 781         for (i = 0; i < table_len; i++)
 782                 if (temp > table[i].temp)
 783                         break;
 784
 785         if (i > 0 && i < table_len) {
 786                 int tmp;
 787
 788                 tmp = (table[i - 1].resistance - table[i].resistance) *
 789                         (temp - table[i].temp);
 790                 tmp /= table[i - 1].temp - table[i].temp;
 791                 resist = tmp + table[i].resistance;
 792         } else if (i == 0) {
 793                 resist = table[0].resistance;
 794         } else {
 795                 resist = table[table_len - 1].resistance;
 796         }
 797
 798         return resist;
 799 }
 800 EXPORT_SYMBOL_GPL(power_supply_temp2resist_simple);
 801
 802 /**
 803  * power_supply_ocv2cap_simple() - find the battery capacity
 804  * @table: Pointer to battery OCV lookup table
 805  * @table_len: OCV table length
 806  * @ocv: Current OCV value
 807  *
 808  * This helper function is used to look up battery capacity according to
 809  * current OCV value from one OCV table, and the OCV table must be ordered
 810  * descending.
 811  *
 812  * Return: the battery capacity.
 813  */
 814 int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
 815                                 int table_len, int ocv)
 816 {
 817         int i, cap, tmp;
 818
 819         for (i = 0; i < table_len; i++)
 820                 if (ocv > table[i].ocv)
 821                         break;
 822
 823         if (i > 0 && i < table_len) {
 824                 tmp = (table[i - 1].capacity - table[i].capacity) *
 825                         (ocv - table[i].ocv);
 826                 tmp /= table[i - 1].ocv - table[i].ocv;
 827                 cap = tmp + table[i].capacity;
 828         } else if (i == 0) {
 829                 cap = table[0].capacity;
 830         } else {
 831                 cap = table[table_len - 1].capacity;
 832         }
 833
 834         return cap;
 835 }
 836 EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple);
 837
 838 struct power_supply_battery_ocv_table *
 839 power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
 840                                 int temp, int *table_len)
 841 {
 842         int best_temp_diff = INT_MAX, temp_diff;
 843         u8 i, best_index = 0;
 844
 845         if (!info->ocv_table[0])
 846                 return NULL;
 847
 848         for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) {
 849                 /* Out of capacity tables */
 850                 if (!info->ocv_table[i])
 851                         break;
 852
 853                 temp_diff = abs(info->ocv_temp[i] - temp);
 854
 855                 if (temp_diff < best_temp_diff) {
 856                         best_temp_diff = temp_diff;
 857                         best_index = i;
 858                 }
 859         }
 860
 861         *table_len = info->ocv_table_size[best_index];
 862         return info->ocv_table[best_index];
 863 }
 864 EXPORT_SYMBOL_GPL(power_supply_find_ocv2cap_table);
 865
 866 int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
 867                                  int ocv, int temp)
 868 {
 869         struct power_supply_battery_ocv_table *table;
 870         int table_len;
 871
 872         table = power_supply_find_ocv2cap_table(info, temp, &table_len);
 873         if (!table)
 874                 return -EINVAL;
 875
 876         return power_supply_ocv2cap_simple(table, table_len, ocv);
 877 }
 878 EXPORT_SYMBOL_GPL(power_supply_batinfo_ocv2cap);
 879
 880 int power_supply_get_property(struct power_supply *psy,
 881                             enum power_supply_property psp,
 882                             union power_supply_propval *val)
 883 {
 884         if (atomic_read(&psy->use_cnt) <= 0) {
 885                 if (!psy->initialized)
 886                         return -EAGAIN;
 887                 return -ENODEV;
 888         }
 889
 890         return psy->desc->get_property(psy, psp, val);
 891 }
 892 EXPORT_SYMBOL_GPL(power_supply_get_property);
 893
 894 int power_supply_set_property(struct power_supply *psy,
 895                             enum power_supply_property psp,
 896                             const union power_supply_propval *val)
 897 {
 898         if (atomic_read(&psy->use_cnt) <= 0 || !psy->desc->set_property)
 899                 return -ENODEV;
 900
 901         return psy->desc->set_property(psy, psp, val);
 902 }
 903 EXPORT_SYMBOL_GPL(power_supply_set_property);
 904
 905 int power_supply_property_is_writeable(struct power_supply *psy,
 906                                         enum power_supply_property psp)
 907 {
 908         if (atomic_read(&psy->use_cnt) <= 0 ||
 909                         !psy->desc->property_is_writeable)
 910                 return -ENODEV;
 911
 912         return psy->desc->property_is_writeable(psy, psp);
 913 }
 914 EXPORT_SYMBOL_GPL(power_supply_property_is_writeable);
 915
 916 void power_supply_external_power_changed(struct power_supply *psy)
 917 {
 918         if (atomic_read(&psy->use_cnt) <= 0 ||
 919                         !psy->desc->external_power_changed)
 920                 return;
 921
 922         psy->desc->external_power_changed(psy);
 923 }
 924 EXPORT_SYMBOL_GPL(power_supply_external_power_changed);
 925
 926 int power_supply_powers(struct power_supply *psy, struct device *dev)
 927 {
 928         return sysfs_create_link(&psy->dev.kobj, &dev->kobj, "powers");
 929 }
 930 EXPORT_SYMBOL_GPL(power_supply_powers);
 931
 932 static void power_supply_dev_release(struct device *dev)
 933 {
 934         struct power_supply *psy = to_power_supply(dev);
 935         dev_dbg(dev, "%s\n", __func__);
 936         kfree(psy);
 937 }
 938
 939 int power_supply_reg_notifier(struct notifier_block *nb)
 940 {
 941         return atomic_notifier_chain_register(&power_supply_notifier, nb);
 942 }
 943 EXPORT_SYMBOL_GPL(power_supply_reg_notifier);
 944
 945 void power_supply_unreg_notifier(struct notifier_block *nb)
 946 {
 947         atomic_notifier_chain_unregister(&power_supply_notifier, nb);
 948 }
 949 EXPORT_SYMBOL_GPL(power_supply_unreg_notifier);
 950
 951 #ifdef CONFIG_THERMAL
 952 static int power_supply_read_temp(struct thermal_zone_device *tzd,
 953                 int *temp)
 954 {
 955         struct power_supply *psy;
 956         union power_supply_propval val;
 957         int ret;
 958
 959         WARN_ON(tzd == NULL);
 960         psy = tzd->devdata;
 961         ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_TEMP, &val);
 962         if (ret)
 963                 return ret;
 964
 965         /* Convert tenths of degree Celsius to milli degree Celsius. */
 966         *temp = val.intval * 100;
 967
 968         return ret;
 969 }
 970
 971 static struct thermal_zone_device_ops psy_tzd_ops = {
 972         .get_temp = power_supply_read_temp,
 973 };
 974
 975 static int psy_register_thermal(struct power_supply *psy)
 976 {
 977         int i, ret;
 978
 979         if (psy->desc->no_thermal)
 980                 return 0;
 981
 982         /* Register battery zone device psy reports temperature */
 983         for (i = 0; i < psy->desc->num_properties; i++) {
 984                 if (psy->desc->properties[i] == POWER_SUPPLY_PROP_TEMP) {
 985                         psy->tzd = thermal_zone_device_register(psy->desc->name,
 986                                         0, 0, psy, &psy_tzd_ops, NULL, 0, 0);
 987                         if (IS_ERR(psy->tzd))
 988                                 return PTR_ERR(psy->tzd);
 989                         ret = thermal_zone_device_enable(psy->tzd);
 990                         if (ret)
 991                                 thermal_zone_device_unregister(psy->tzd);
 992                         return ret;
 993                 }
 994         }
 995         return 0;
 996 }
 997
 998 static void psy_unregister_thermal(struct power_supply *psy)
 999 {
1000         if (IS_ERR_OR_NULL(psy->tzd))
1001                 return;
1002         thermal_zone_device_unregister(psy->tzd);
1003 }
1004
1005 /* thermal cooling device callbacks */
1006 static int ps_get_max_charge_cntl_limit(struct thermal_cooling_device *tcd,
1007                                         unsigned long *state)
1008 {
1009         struct power_supply *psy;
1010         union power_supply_propval val;
1011         int ret;
1012
1013         psy = tcd->devdata;
1014         ret = power_supply_get_property(psy,
1015                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX, &val);
1016         if (ret)
1017                 return ret;
1018
1019         *state = val.intval;
1020
1021         return ret;
1022 }
1023
1024 static int ps_get_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
1025                                         unsigned long *state)
1026 {
1027         struct power_supply *psy;
1028         union power_supply_propval val;
1029         int ret;
1030
1031         psy = tcd->devdata;
1032         ret = power_supply_get_property(psy,
1033                         POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
1034         if (ret)
1035                 return ret;
1036
1037         *state = val.intval;
1038
1039         return ret;
1040 }
1041
1042 static int ps_set_cur_charge_cntl_limit(struct thermal_cooling_device *tcd,
1043                                         unsigned long state)
1044 {
1045         struct power_supply *psy;
1046         union power_supply_propval val;
1047         int ret;
1048
1049         psy = tcd->devdata;
1050         val.intval = state;
1051         ret = psy->desc->set_property(psy,
1052                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT, &val);
1053
1054         return ret;
1055 }
1056
1057 static const struct thermal_cooling_device_ops psy_tcd_ops = {
1058         .get_max_state = ps_get_max_charge_cntl_limit,
1059         .get_cur_state = ps_get_cur_charge_cntl_limit,
1060         .set_cur_state = ps_set_cur_charge_cntl_limit,
1061 };
1062
1063 static int psy_register_cooler(struct power_supply *psy)
1064 {
1065         int i;
1066
1067         /* Register for cooling device if psy can control charging */
1068         for (i = 0; i < psy->desc->num_properties; i++) {
1069                 if (psy->desc->properties[i] ==
1070                                 POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT) {
1071                         psy->tcd = thermal_cooling_device_register(
1072                                                         (char *)psy->desc->name,
1073                                                         psy, &psy_tcd_ops);
1074                         return PTR_ERR_OR_ZERO(psy->tcd);
1075                 }
1076         }
1077         return 0;
1078 }
1079
1080 static void psy_unregister_cooler(struct power_supply *psy)
1081 {
1082         if (IS_ERR_OR_NULL(psy->tcd))
1083                 return;
1084         thermal_cooling_device_unregister(psy->tcd);
1085 }
1086 #else
1087 static int psy_register_thermal(struct power_supply *psy)
1088 {
1089         return 0;
1090 }
1091
1092 static void psy_unregister_thermal(struct power_supply *psy)
1093 {
1094 }
1095
1096 static int psy_register_cooler(struct power_supply *psy)
1097 {
1098         return 0;
1099 }
1100
1101 static void psy_unregister_cooler(struct power_supply *psy)
1102 {
1103 }
1104 #endif
1105
1106 static struct power_supply *__must_check
1107 __power_supply_register(struct device *parent,
1108                                    const struct power_supply_desc *desc,
1109                                    const struct power_supply_config *cfg,
1110                                    bool ws)
1111 {
1112         struct device *dev;
1113         struct power_supply *psy;
1114         int i, rc;
1115
1116         if (!parent)
1117                 pr_warn("%s: Expected proper parent device for '%s'\n",
1118                         __func__, desc->name);
1119
1120         if (!desc || !desc->name || !desc->properties || !desc->num_properties)
1121                 return ERR_PTR(-EINVAL);
1122
1123         for (i = 0; i < desc->num_properties; ++i) {
1124                 if ((desc->properties[i] == POWER_SUPPLY_PROP_USB_TYPE) &&
1125                     (!desc->usb_types || !desc->num_usb_types))
1126                         return ERR_PTR(-EINVAL);
1127         }
1128
1129         psy = kzalloc(sizeof(*psy), GFP_KERNEL);
1130         if (!psy)
1131                 return ERR_PTR(-ENOMEM);
1132
1133         dev = &psy->dev;
1134
1135         device_initialize(dev);
1136
1137         dev->class = power_supply_class;
1138         dev->type = &power_supply_dev_type;
1139         dev->parent = parent;
1140         dev->release = power_supply_dev_release;
1141         dev_set_drvdata(dev, psy);
1142         psy->desc = desc;
1143         if (cfg) {
1144                 dev->groups = cfg->attr_grp;
1145                 psy->drv_data = cfg->drv_data;
1146                 psy->of_node =
1147                         cfg->fwnode ? to_of_node(cfg->fwnode) : cfg->of_node;
1148                 psy->supplied_to = cfg->supplied_to;
1149                 psy->num_supplicants = cfg->num_supplicants;
1150         }
1151
1152         rc = dev_set_name(dev, "%s", desc->name);
1153         if (rc)
1154                 goto dev_set_name_failed;
1155
1156         INIT_WORK(&psy->changed_work, power_supply_changed_work);
1157         INIT_DELAYED_WORK(&psy->deferred_register_work,
1158                           power_supply_deferred_register_work);
1159
1160         rc = power_supply_check_supplies(psy);
1161         if (rc) {
1162                 dev_info(dev, "Not all required supplies found, defer probe\n");
1163                 goto check_supplies_failed;
1164         }
1165
1166         spin_lock_init(&psy->changed_lock);
1167         rc = device_add(dev);
1168         if (rc)
1169                 goto device_add_failed;
1170
1171         rc = device_init_wakeup(dev, ws);
1172         if (rc)
1173                 goto wakeup_init_failed;
1174
1175         rc = psy_register_thermal(psy);
1176         if (rc)
1177                 goto register_thermal_failed;
1178
1179         rc = psy_register_cooler(psy);
1180         if (rc)
1181                 goto register_cooler_failed;
1182
1183         rc = power_supply_create_triggers(psy);
1184         if (rc)
1185                 goto create_triggers_failed;
1186
1187         rc = power_supply_add_hwmon_sysfs(psy);
1188         if (rc)
1189                 goto add_hwmon_sysfs_failed;
1190
1191         /*
1192          * Update use_cnt after any uevents (most notably from device_add()).
1193          * We are here still during driver's probe but
1194          * the power_supply_uevent() calls back driver's get_property
1195          * method so:
1196          * 1. Driver did not assigned the returned struct power_supply,
1197          * 2. Driver could not finish initialization (anything in its probe
1198          *    after calling power_supply_register()).
1199          */
1200         atomic_inc(&psy->use_cnt);
1201         psy->initialized = true;
1202
1203         queue_delayed_work(system_power_efficient_wq,
1204                            &psy->deferred_register_work,
1205                            POWER_SUPPLY_DEFERRED_REGISTER_TIME);
1206
1207         return psy;
1208
1209 add_hwmon_sysfs_failed:
1210         power_supply_remove_triggers(psy);
1211 create_triggers_failed:
1212         psy_unregister_cooler(psy);
1213 register_cooler_failed:
1214         psy_unregister_thermal(psy);
1215 register_thermal_failed:
1216 wakeup_init_failed:
1217         device_del(dev);
1218 device_add_failed:
1219 check_supplies_failed:
1220 dev_set_name_failed:
1221         put_device(dev);
1222         return ERR_PTR(rc);
1223 }
1224
1225 /**
1226  * power_supply_register() - Register new power supply
1227  * @parent:     Device to be a parent of power supply's device, usually
1228  *              the device which probe function calls this
1229  * @desc:       Description of power supply, must be valid through whole
1230  *              lifetime of this power supply
1231  * @cfg:        Run-time specific configuration accessed during registering,
1232  *              may be NULL
1233  *
1234  * Return: A pointer to newly allocated power_supply on success
1235  * or ERR_PTR otherwise.
1236  * Use power_supply_unregister() on returned power_supply pointer to release
1237  * resources.
1238  */
1239 struct power_supply *__must_check power_supply_register(struct device *parent,
1240                 const struct power_supply_desc *desc,
1241                 const struct power_supply_config *cfg)
1242 {
1243         return __power_supply_register(parent, desc, cfg, true);
1244 }
1245 EXPORT_SYMBOL_GPL(power_supply_register);
1246
1247 /**
1248  * power_supply_register_no_ws() - Register new non-waking-source power supply
1249  * @parent:     Device to be a parent of power supply's device, usually
1250  *              the device which probe function calls this
1251  * @desc:       Description of power supply, must be valid through whole
1252  *              lifetime of this power supply
1253  * @cfg:        Run-time specific configuration accessed during registering,
1254  *              may be NULL
1255  *
1256  * Return: A pointer to newly allocated power_supply on success
1257  * or ERR_PTR otherwise.
1258  * Use power_supply_unregister() on returned power_supply pointer to release
1259  * resources.
1260  */
1261 struct power_supply *__must_check
1262 power_supply_register_no_ws(struct device *parent,
1263                 const struct power_supply_desc *desc,
1264                 const struct power_supply_config *cfg)
1265 {
1266         return __power_supply_register(parent, desc, cfg, false);
1267 }
1268 EXPORT_SYMBOL_GPL(power_supply_register_no_ws);
1269
1270 static void devm_power_supply_release(struct device *dev, void *res)
1271 {
1272         struct power_supply **psy = res;
1273
1274         power_supply_unregister(*psy);
1275 }
1276
1277 /**
1278  * devm_power_supply_register() - Register managed power supply
1279  * @parent:     Device to be a parent of power supply's device, usually
1280  *              the device which probe function calls this
1281  * @desc:       Description of power supply, must be valid through whole
1282  *              lifetime of this power supply
1283  * @cfg:        Run-time specific configuration accessed during registering,
1284  *              may be NULL
1285  *
1286  * Return: A pointer to newly allocated power_supply on success
1287  * or ERR_PTR otherwise.
1288  * The returned power_supply pointer will be automatically unregistered
1289  * on driver detach.
1290  */
1291 struct power_supply *__must_check
1292 devm_power_supply_register(struct device *parent,
1293                 const struct power_supply_desc *desc,
1294                 const struct power_supply_config *cfg)
1295 {
1296         struct power_supply **ptr, *psy;
1297
1298         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
1299
1300         if (!ptr)
1301                 return ERR_PTR(-ENOMEM);
1302         psy = __power_supply_register(parent, desc, cfg, true);
1303         if (IS_ERR(psy)) {
1304                 devres_free(ptr);
1305         } else {
1306                 *ptr = psy;
1307                 devres_add(parent, ptr);
1308         }
1309         return psy;
1310 }
1311 EXPORT_SYMBOL_GPL(devm_power_supply_register);
1312
1313 /**
1314  * devm_power_supply_register_no_ws() - Register managed non-waking-source power supply
1315  * @parent:     Device to be a parent of power supply's device, usually
1316  *              the device which probe function calls this
1317  * @desc:       Description of power supply, must be valid through whole
1318  *              lifetime of this power supply
1319  * @cfg:        Run-time specific configuration accessed during registering,
1320  *              may be NULL
1321  *
1322  * Return: A pointer to newly allocated power_supply on success
1323  * or ERR_PTR otherwise.
1324  * The returned power_supply pointer will be automatically unregistered
1325  * on driver detach.
1326  */
1327 struct power_supply *__must_check
1328 devm_power_supply_register_no_ws(struct device *parent,
1329                 const struct power_supply_desc *desc,
1330                 const struct power_supply_config *cfg)
1331 {
1332         struct power_supply **ptr, *psy;
1333
1334         ptr = devres_alloc(devm_power_supply_release, sizeof(*ptr), GFP_KERNEL);
1335
1336         if (!ptr)
1337                 return ERR_PTR(-ENOMEM);
1338         psy = __power_supply_register(parent, desc, cfg, false);
1339         if (IS_ERR(psy)) {
1340                 devres_free(ptr);
1341         } else {
1342                 *ptr = psy;
1343                 devres_add(parent, ptr);
1344         }
1345         return psy;
1346 }
1347 EXPORT_SYMBOL_GPL(devm_power_supply_register_no_ws);
1348
1349 /**
1350  * power_supply_unregister() - Remove this power supply from system
1351  * @psy:        Pointer to power supply to unregister
1352  *
1353  * Remove this power supply from the system. The resources of power supply
1354  * will be freed here or on last power_supply_put() call.
1355  */
1356 void power_supply_unregister(struct power_supply *psy)
1357 {
1358         WARN_ON(atomic_dec_return(&psy->use_cnt));
1359         psy->removing = true;
1360         cancel_work_sync(&psy->changed_work);
1361         cancel_delayed_work_sync(&psy->deferred_register_work);
1362         sysfs_remove_link(&psy->dev.kobj, "powers");
1363         power_supply_remove_hwmon_sysfs(psy);
1364         power_supply_remove_triggers(psy);
1365         psy_unregister_cooler(psy);
1366         psy_unregister_thermal(psy);
1367         device_init_wakeup(&psy->dev, false);
1368         device_unregister(&psy->dev);
1369 }
1370 EXPORT_SYMBOL_GPL(power_supply_unregister);
1371
1372 void *power_supply_get_drvdata(struct power_supply *psy)
1373 {
1374         return psy->drv_data;
1375 }
1376 EXPORT_SYMBOL_GPL(power_supply_get_drvdata);
1377
1378 static int __init power_supply_class_init(void)
1379 {
1380         power_supply_class = class_create(THIS_MODULE, "power_supply");
1381
1382         if (IS_ERR(power_supply_class))
1383                 return PTR_ERR(power_supply_class);
1384
1385         power_supply_class->dev_uevent = power_supply_uevent;
1386         power_supply_init_attrs(&power_supply_dev_type);
1387
1388         return 0;
1389 }
1390
1391 static void __exit power_supply_class_exit(void)
1392 {
1393         class_destroy(power_supply_class);
1394 }
1395
1396 subsys_initcall(power_supply_class_init);
1397 module_exit(power_supply_class_exit);
1398
1399 MODULE_DESCRIPTION("Universal power supply monitor class");
1400 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>, "
1401               "Szabolcs Gyurko, "
1402               "Anton Vorontsov <cbou@mail.ru>");
1403 MODULE_LICENSE("GPL");