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