drivers/thermal/thermal_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/export.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <linux/suspend.h>
  23
  24 #define CREATE_TRACE_POINTS
  25 #include <trace/events/thermal.h>
  26
  27 #include "thermal_core.h"
  28 #include "thermal_hwmon.h"
  29
  30 static DEFINE_IDA(thermal_tz_ida);
  31 static DEFINE_IDA(thermal_cdev_ida);
  32
  33 static LIST_HEAD(thermal_tz_list);
  34 static LIST_HEAD(thermal_cdev_list);
  35 static LIST_HEAD(thermal_governor_list);
  36
  37 static DEFINE_MUTEX(thermal_list_lock);
  38 static DEFINE_MUTEX(thermal_governor_lock);
  39
  40 static atomic_t in_suspend;
  41
  42 static struct thermal_governor *def_governor;
  43
  44 /*
  45  * Governor section: set of functions to handle thermal governors
  46  *
  47  * Functions to help in the life cycle of thermal governors within
  48  * the thermal core and by the thermal governor code.
  49  */
  50
  51 static struct thermal_governor *__find_governor(const char *name)
  52 {
  53         struct thermal_governor *pos;
  54
  55         if (!name || !name[0])
  56                 return def_governor;
  57
  58         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  59                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  60                         return pos;
  61
  62         return NULL;
  63 }
  64
  65 /**
  66  * bind_previous_governor() - bind the previous governor of the thermal zone
  67  * @tz:         a valid pointer to a struct thermal_zone_device
  68  * @failed_gov_name:    the name of the governor that failed to register
  69  *
  70  * Register the previous governor of the thermal zone after a new
  71  * governor has failed to be bound.
  72  */
  73 static void bind_previous_governor(struct thermal_zone_device *tz,
  74                                    const char *failed_gov_name)
  75 {
  76         if (tz->governor && tz->governor->bind_to_tz) {
  77                 if (tz->governor->bind_to_tz(tz)) {
  78                         dev_err(&tz->device,
  79                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  80                                 failed_gov_name, tz->governor->name, tz->type);
  81                         tz->governor = NULL;
  82                 }
  83         }
  84 }
  85
  86 /**
  87  * thermal_set_governor() - Switch to another governor
  88  * @tz:         a valid pointer to a struct thermal_zone_device
  89  * @new_gov:    pointer to the new governor
  90  *
  91  * Change the governor of thermal zone @tz.
  92  *
  93  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  94  */
  95 static int thermal_set_governor(struct thermal_zone_device *tz,
  96                                 struct thermal_governor *new_gov)
  97 {
  98         int ret = 0;
  99
 100         if (tz->governor && tz->governor->unbind_from_tz)
 101                 tz->governor->unbind_from_tz(tz);
 102
 103         if (new_gov && new_gov->bind_to_tz) {
 104                 ret = new_gov->bind_to_tz(tz);
 105                 if (ret) {
 106                         bind_previous_governor(tz, new_gov->name);
 107
 108                         return ret;
 109                 }
 110         }
 111
 112         tz->governor = new_gov;
 113
 114         return ret;
 115 }
 116
 117 int thermal_register_governor(struct thermal_governor *governor)
 118 {
 119         int err;
 120         const char *name;
 121         struct thermal_zone_device *pos;
 122
 123         if (!governor)
 124                 return -EINVAL;
 125
 126         mutex_lock(&thermal_governor_lock);
 127
 128         err = -EBUSY;
 129         if (!__find_governor(governor->name)) {
 130                 bool match_default;
 131
 132                 err = 0;
 133                 list_add(&governor->governor_list, &thermal_governor_list);
 134                 match_default = !strncmp(governor->name,
 135                                          DEFAULT_THERMAL_GOVERNOR,
 136                                          THERMAL_NAME_LENGTH);
 137
 138                 if (!def_governor && match_default)
 139                         def_governor = governor;
 140         }
 141
 142         mutex_lock(&thermal_list_lock);
 143
 144         list_for_each_entry(pos, &thermal_tz_list, node) {
 145                 /*
 146                  * only thermal zones with specified tz->tzp->governor_name
 147                  * may run with tz->govenor unset
 148                  */
 149                 if (pos->governor)
 150                         continue;
 151
 152                 name = pos->tzp->governor_name;
 153
 154                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 155                         int ret;
 156
 157                         ret = thermal_set_governor(pos, governor);
 158                         if (ret)
 159                                 dev_err(&pos->device,
 160                                         "Failed to set governor %s for thermal zone %s: %d\n",
 161                                         governor->name, pos->type, ret);
 162                 }
 163         }
 164
 165         mutex_unlock(&thermal_list_lock);
 166         mutex_unlock(&thermal_governor_lock);
 167
 168         return err;
 169 }
 170
 171 void thermal_unregister_governor(struct thermal_governor *governor)
 172 {
 173         struct thermal_zone_device *pos;
 174
 175         if (!governor)
 176                 return;
 177
 178         mutex_lock(&thermal_governor_lock);
 179
 180         if (!__find_governor(governor->name))
 181                 goto exit;
 182
 183         mutex_lock(&thermal_list_lock);
 184
 185         list_for_each_entry(pos, &thermal_tz_list, node) {
 186                 if (!strncasecmp(pos->governor->name, governor->name,
 187                                  THERMAL_NAME_LENGTH))
 188                         thermal_set_governor(pos, NULL);
 189         }
 190
 191         mutex_unlock(&thermal_list_lock);
 192         list_del(&governor->governor_list);
 193 exit:
 194         mutex_unlock(&thermal_governor_lock);
 195 }
 196
 197 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 198                                    char *policy)
 199 {
 200         struct thermal_governor *gov;
 201         int ret = -EINVAL;
 202
 203         mutex_lock(&thermal_governor_lock);
 204         mutex_lock(&tz->lock);
 205
 206         gov = __find_governor(strim(policy));
 207         if (!gov)
 208                 goto exit;
 209
 210         ret = thermal_set_governor(tz, gov);
 211
 212 exit:
 213         mutex_unlock(&tz->lock);
 214         mutex_unlock(&thermal_governor_lock);
 215
 216         thermal_notify_tz_gov_change(tz->id, policy);
 217
 218         return ret;
 219 }
 220
 221 int thermal_build_list_of_policies(char *buf)
 222 {
 223         struct thermal_governor *pos;
 224         ssize_t count = 0;
 225
 226         mutex_lock(&thermal_governor_lock);
 227
 228         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 229                 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
 230                                    pos->name);
 231         }
 232         count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
 233
 234         mutex_unlock(&thermal_governor_lock);
 235
 236         return count;
 237 }
 238
 239 static void __init thermal_unregister_governors(void)
 240 {
 241         struct thermal_governor **governor;
 242
 243         for_each_governor_table(governor)
 244                 thermal_unregister_governor(*governor);
 245 }
 246
 247 static int __init thermal_register_governors(void)
 248 {
 249         int ret = 0;
 250         struct thermal_governor **governor;
 251
 252         for_each_governor_table(governor) {
 253                 ret = thermal_register_governor(*governor);
 254                 if (ret) {
 255                         pr_err("Failed to register governor: '%s'",
 256                                (*governor)->name);
 257                         break;
 258                 }
 259
 260                 pr_info("Registered thermal governor '%s'",
 261                         (*governor)->name);
 262         }
 263
 264         if (ret) {
 265                 struct thermal_governor **gov;
 266
 267                 for_each_governor_table(gov) {
 268                         if (gov == governor)
 269                                 break;
 270                         thermal_unregister_governor(*gov);
 271                 }
 272         }
 273
 274         return ret;
 275 }
 276
 277 /*
 278  * Zone update section: main control loop applied to each zone while monitoring
 279  *
 280  * in polling mode. The monitoring is done using a workqueue.
 281  * Same update may be done on a zone by calling thermal_zone_device_update().
 282  *
 283  * An update means:
 284  * - Non-critical trips will invoke the governor responsible for that zone;
 285  * - Hot trips will produce a notification to userspace;
 286  * - Critical trip point will cause a system shutdown.
 287  */
 288 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 289                                             unsigned long delay)
 290 {
 291         if (delay)
 292                 mod_delayed_work(system_freezable_power_efficient_wq,
 293                                  &tz->poll_queue, delay);
 294         else
 295                 cancel_delayed_work(&tz->poll_queue);
 296 }
 297
 298 static inline bool should_stop_polling(struct thermal_zone_device *tz)
 299 {
 300         return !thermal_zone_device_is_enabled(tz);
 301 }
 302
 303 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 304 {
 305         bool stop;
 306
 307         stop = should_stop_polling(tz);
 308
 309         mutex_lock(&tz->lock);
 310
 311         if (!stop && tz->passive)
 312                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 313         else if (!stop && tz->polling_delay_jiffies)
 314                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 315         else
 316                 thermal_zone_device_set_polling(tz, 0);
 317
 318         mutex_unlock(&tz->lock);
 319 }
 320
 321 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 322 {
 323         tz->governor ? tz->governor->throttle(tz, trip) :
 324                        def_governor->throttle(tz, trip);
 325 }
 326
 327 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 328 {
 329         /*
 330          * poweroff_delay_ms must be a carefully profiled positive value.
 331          * Its a must for forced_emergency_poweroff_work to be scheduled.
 332          */
 333         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 334
 335         dev_emerg(&tz->device, "%s: critical temperature reached, "
 336                   "shutting down\n", tz->type);
 337
 338         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
 339 }
 340 EXPORT_SYMBOL(thermal_zone_device_critical);
 341
 342 static void handle_critical_trips(struct thermal_zone_device *tz,
 343                                   int trip, enum thermal_trip_type trip_type)
 344 {
 345         int trip_temp;
 346
 347         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 348
 349         /* If we have not crossed the trip_temp, we do not care. */
 350         if (trip_temp <= 0 || tz->temperature < trip_temp)
 351                 return;
 352
 353         trace_thermal_zone_trip(tz, trip, trip_type);
 354
 355         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
 356                 tz->ops->hot(tz);
 357         else if (trip_type == THERMAL_TRIP_CRITICAL)
 358                 tz->ops->critical(tz);
 359 }
 360
 361 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 362 {
 363         enum thermal_trip_type type;
 364         int trip_temp, hyst = 0;
 365
 366         /* Ignore disabled trip points */
 367         if (test_bit(trip, &tz->trips_disabled))
 368                 return;
 369
 370         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 371         tz->ops->get_trip_type(tz, trip, &type);
 372         if (tz->ops->get_trip_hyst)
 373                 tz->ops->get_trip_hyst(tz, trip, &hyst);
 374
 375         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 376                 if (tz->last_temperature < trip_temp &&
 377                     tz->temperature >= trip_temp)
 378                         thermal_notify_tz_trip_up(tz->id, trip,
 379                                                   tz->temperature);
 380                 if (tz->last_temperature >= trip_temp &&
 381                     tz->temperature < (trip_temp - hyst))
 382                         thermal_notify_tz_trip_down(tz->id, trip,
 383                                                     tz->temperature);
 384         }
 385
 386         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 387                 handle_critical_trips(tz, trip, type);
 388         else
 389                 handle_non_critical_trips(tz, trip);
 390         /*
 391          * Alright, we handled this trip successfully.
 392          * So, start monitoring again.
 393          */
 394         monitor_thermal_zone(tz);
 395 }
 396
 397 static void update_temperature(struct thermal_zone_device *tz)
 398 {
 399         int temp, ret;
 400
 401         ret = thermal_zone_get_temp(tz, &temp);
 402         if (ret) {
 403                 if (ret != -EAGAIN)
 404                         dev_warn(&tz->device,
 405                                  "failed to read out thermal zone (%d)\n",
 406                                  ret);
 407                 return;
 408         }
 409
 410         mutex_lock(&tz->lock);
 411         tz->last_temperature = tz->temperature;
 412         tz->temperature = temp;
 413         mutex_unlock(&tz->lock);
 414
 415         trace_thermal_temperature(tz);
 416
 417         thermal_genl_sampling_temp(tz->id, temp);
 418 }
 419
 420 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 421 {
 422         struct thermal_instance *pos;
 423         tz->temperature = THERMAL_TEMP_INVALID;
 424         tz->prev_low_trip = -INT_MAX;
 425         tz->prev_high_trip = INT_MAX;
 426         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 427                 pos->initialized = false;
 428 }
 429
 430 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 431                                         enum thermal_device_mode mode)
 432 {
 433         int ret = 0;
 434
 435         mutex_lock(&tz->lock);
 436
 437         /* do nothing if mode isn't changing */
 438         if (mode == tz->mode) {
 439                 mutex_unlock(&tz->lock);
 440
 441                 return ret;
 442         }
 443
 444         if (tz->ops->change_mode)
 445                 ret = tz->ops->change_mode(tz, mode);
 446
 447         if (!ret)
 448                 tz->mode = mode;
 449
 450         mutex_unlock(&tz->lock);
 451
 452         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 453
 454         if (mode == THERMAL_DEVICE_ENABLED)
 455                 thermal_notify_tz_enable(tz->id);
 456         else
 457                 thermal_notify_tz_disable(tz->id);
 458
 459         return ret;
 460 }
 461
 462 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 463 {
 464         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 465 }
 466 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 467
 468 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 469 {
 470         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 471 }
 472 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 473
 474 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 475 {
 476         enum thermal_device_mode mode;
 477
 478         mutex_lock(&tz->lock);
 479
 480         mode = tz->mode;
 481
 482         mutex_unlock(&tz->lock);
 483
 484         return mode == THERMAL_DEVICE_ENABLED;
 485 }
 486
 487 void thermal_zone_device_update(struct thermal_zone_device *tz,
 488                                 enum thermal_notify_event event)
 489 {
 490         int count;
 491
 492         if (should_stop_polling(tz))
 493                 return;
 494
 495         if (atomic_read(&in_suspend))
 496                 return;
 497
 498         if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
 499                       "'get_temp' ops set\n", __func__))
 500                 return;
 501
 502         update_temperature(tz);
 503
 504         thermal_zone_set_trips(tz);
 505
 506         tz->notify_event = event;
 507
 508         for (count = 0; count < tz->trips; count++)
 509                 handle_thermal_trip(tz, count);
 510 }
 511 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 512
 513 static void thermal_zone_device_check(struct work_struct *work)
 514 {
 515         struct thermal_zone_device *tz = container_of(work, struct
 516                                                       thermal_zone_device,
 517                                                       poll_queue.work);
 518         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 519 }
 520
 521 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 522                               void *data)
 523 {
 524         struct thermal_governor *gov;
 525         int ret = 0;
 526
 527         mutex_lock(&thermal_governor_lock);
 528         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 529                 ret = cb(gov, data);
 530                 if (ret)
 531                         break;
 532         }
 533         mutex_unlock(&thermal_governor_lock);
 534
 535         return ret;
 536 }
 537
 538 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 539                                               void *), void *data)
 540 {
 541         struct thermal_cooling_device *cdev;
 542         int ret = 0;
 543
 544         mutex_lock(&thermal_list_lock);
 545         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 546                 ret = cb(cdev, data);
 547                 if (ret)
 548                         break;
 549         }
 550         mutex_unlock(&thermal_list_lock);
 551
 552         return ret;
 553 }
 554
 555 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 556                           void *data)
 557 {
 558         struct thermal_zone_device *tz;
 559         int ret = 0;
 560
 561         mutex_lock(&thermal_list_lock);
 562         list_for_each_entry(tz, &thermal_tz_list, node) {
 563                 ret = cb(tz, data);
 564                 if (ret)
 565                         break;
 566         }
 567         mutex_unlock(&thermal_list_lock);
 568
 569         return ret;
 570 }
 571
 572 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 573 {
 574         struct thermal_zone_device *tz, *match = NULL;
 575
 576         mutex_lock(&thermal_list_lock);
 577         list_for_each_entry(tz, &thermal_tz_list, node) {
 578                 if (tz->id == id) {
 579                         match = tz;
 580                         break;
 581                 }
 582         }
 583         mutex_unlock(&thermal_list_lock);
 584
 585         return match;
 586 }
 587
 588 /*
 589  * Device management section: cooling devices, zones devices, and binding
 590  *
 591  * Set of functions provided by the thermal core for:
 592  * - cooling devices lifecycle: registration, unregistration,
 593  *                              binding, and unbinding.
 594  * - thermal zone devices lifecycle: registration, unregistration,
 595  *                                   binding, and unbinding.
 596  */
 597
 598 /**
 599  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 600  * @tz:         pointer to struct thermal_zone_device
 601  * @trip:       indicates which trip point the cooling devices is
 602  *              associated with in this thermal zone.
 603  * @cdev:       pointer to struct thermal_cooling_device
 604  * @upper:      the Maximum cooling state for this trip point.
 605  *              THERMAL_NO_LIMIT means no upper limit,
 606  *              and the cooling device can be in max_state.
 607  * @lower:      the Minimum cooling state can be used for this trip point.
 608  *              THERMAL_NO_LIMIT means no lower limit,
 609  *              and the cooling device can be in cooling state 0.
 610  * @weight:     The weight of the cooling device to be bound to the
 611  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 612  *              default value
 613  *
 614  * This interface function bind a thermal cooling device to the certain trip
 615  * point of a thermal zone device.
 616  * This function is usually called in the thermal zone device .bind callback.
 617  *
 618  * Return: 0 on success, the proper error value otherwise.
 619  */
 620 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 621                                      int trip,
 622                                      struct thermal_cooling_device *cdev,
 623                                      unsigned long upper, unsigned long lower,
 624                                      unsigned int weight)
 625 {
 626         struct thermal_instance *dev;
 627         struct thermal_instance *pos;
 628         struct thermal_zone_device *pos1;
 629         struct thermal_cooling_device *pos2;
 630         unsigned long max_state;
 631         int result, ret;
 632
 633         if (trip >= tz->trips || trip < 0)
 634                 return -EINVAL;
 635
 636         list_for_each_entry(pos1, &thermal_tz_list, node) {
 637                 if (pos1 == tz)
 638                         break;
 639         }
 640         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 641                 if (pos2 == cdev)
 642                         break;
 643         }
 644
 645         if (tz != pos1 || cdev != pos2)
 646                 return -EINVAL;
 647
 648         ret = cdev->ops->get_max_state(cdev, &max_state);
 649         if (ret)
 650                 return ret;
 651
 652         /* lower default 0, upper default max_state */
 653         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 654         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 655
 656         if (lower > upper || upper > max_state)
 657                 return -EINVAL;
 658
 659         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 660         if (!dev)
 661                 return -ENOMEM;
 662         dev->tz = tz;
 663         dev->cdev = cdev;
 664         dev->trip = trip;
 665         dev->upper = upper;
 666         dev->lower = lower;
 667         dev->target = THERMAL_NO_TARGET;
 668         dev->weight = weight;
 669
 670         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 671         if (result < 0)
 672                 goto free_mem;
 673
 674         dev->id = result;
 675         sprintf(dev->name, "cdev%d", dev->id);
 676         result =
 677             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 678         if (result)
 679                 goto release_ida;
 680
 681         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 682         sysfs_attr_init(&dev->attr.attr);
 683         dev->attr.attr.name = dev->attr_name;
 684         dev->attr.attr.mode = 0444;
 685         dev->attr.show = trip_point_show;
 686         result = device_create_file(&tz->device, &dev->attr);
 687         if (result)
 688                 goto remove_symbol_link;
 689
 690         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 691         sysfs_attr_init(&dev->weight_attr.attr);
 692         dev->weight_attr.attr.name = dev->weight_attr_name;
 693         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 694         dev->weight_attr.show = weight_show;
 695         dev->weight_attr.store = weight_store;
 696         result = device_create_file(&tz->device, &dev->weight_attr);
 697         if (result)
 698                 goto remove_trip_file;
 699
 700         mutex_lock(&tz->lock);
 701         mutex_lock(&cdev->lock);
 702         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 703                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 704                         result = -EEXIST;
 705                         break;
 706                 }
 707         if (!result) {
 708                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 709                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 710                 atomic_set(&tz->need_update, 1);
 711         }
 712         mutex_unlock(&cdev->lock);
 713         mutex_unlock(&tz->lock);
 714
 715         if (!result)
 716                 return 0;
 717
 718         device_remove_file(&tz->device, &dev->weight_attr);
 719 remove_trip_file:
 720         device_remove_file(&tz->device, &dev->attr);
 721 remove_symbol_link:
 722         sysfs_remove_link(&tz->device.kobj, dev->name);
 723 release_ida:
 724         ida_simple_remove(&tz->ida, dev->id);
 725 free_mem:
 726         kfree(dev);
 727         return result;
 728 }
 729 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 730
 731 /**
 732  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 733  *                                        thermal zone.
 734  * @tz:         pointer to a struct thermal_zone_device.
 735  * @trip:       indicates which trip point the cooling devices is
 736  *              associated with in this thermal zone.
 737  * @cdev:       pointer to a struct thermal_cooling_device.
 738  *
 739  * This interface function unbind a thermal cooling device from the certain
 740  * trip point of a thermal zone device.
 741  * This function is usually called in the thermal zone device .unbind callback.
 742  *
 743  * Return: 0 on success, the proper error value otherwise.
 744  */
 745 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 746                                        int trip,
 747                                        struct thermal_cooling_device *cdev)
 748 {
 749         struct thermal_instance *pos, *next;
 750
 751         mutex_lock(&tz->lock);
 752         mutex_lock(&cdev->lock);
 753         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 754                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 755                         list_del(&pos->tz_node);
 756                         list_del(&pos->cdev_node);
 757                         mutex_unlock(&cdev->lock);
 758                         mutex_unlock(&tz->lock);
 759                         goto unbind;
 760                 }
 761         }
 762         mutex_unlock(&cdev->lock);
 763         mutex_unlock(&tz->lock);
 764
 765         return -ENODEV;
 766
 767 unbind:
 768         device_remove_file(&tz->device, &pos->weight_attr);
 769         device_remove_file(&tz->device, &pos->attr);
 770         sysfs_remove_link(&tz->device.kobj, pos->name);
 771         ida_simple_remove(&tz->ida, pos->id);
 772         kfree(pos);
 773         return 0;
 774 }
 775 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 776
 777 static void thermal_release(struct device *dev)
 778 {
 779         struct thermal_zone_device *tz;
 780         struct thermal_cooling_device *cdev;
 781
 782         if (!strncmp(dev_name(dev), "thermal_zone",
 783                      sizeof("thermal_zone") - 1)) {
 784                 tz = to_thermal_zone(dev);
 785                 thermal_zone_destroy_device_groups(tz);
 786                 kfree(tz);
 787         } else if (!strncmp(dev_name(dev), "cooling_device",
 788                             sizeof("cooling_device") - 1)) {
 789                 cdev = to_cooling_device(dev);
 790                 kfree(cdev);
 791         }
 792 }
 793
 794 static struct class thermal_class = {
 795         .name = "thermal",
 796         .dev_release = thermal_release,
 797 };
 798
 799 static inline
 800 void print_bind_err_msg(struct thermal_zone_device *tz,
 801                         struct thermal_cooling_device *cdev, int ret)
 802 {
 803         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 804                 tz->type, cdev->type, ret);
 805 }
 806
 807 static void __bind(struct thermal_zone_device *tz, int mask,
 808                    struct thermal_cooling_device *cdev,
 809                    unsigned long *limits,
 810                    unsigned int weight)
 811 {
 812         int i, ret;
 813
 814         for (i = 0; i < tz->trips; i++) {
 815                 if (mask & (1 << i)) {
 816                         unsigned long upper, lower;
 817
 818                         upper = THERMAL_NO_LIMIT;
 819                         lower = THERMAL_NO_LIMIT;
 820                         if (limits) {
 821                                 lower = limits[i * 2];
 822                                 upper = limits[i * 2 + 1];
 823                         }
 824                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 825                                                                upper, lower,
 826                                                                weight);
 827                         if (ret)
 828                                 print_bind_err_msg(tz, cdev, ret);
 829                 }
 830         }
 831 }
 832
 833 static void bind_cdev(struct thermal_cooling_device *cdev)
 834 {
 835         int i, ret;
 836         const struct thermal_zone_params *tzp;
 837         struct thermal_zone_device *pos = NULL;
 838
 839         mutex_lock(&thermal_list_lock);
 840
 841         list_for_each_entry(pos, &thermal_tz_list, node) {
 842                 if (!pos->tzp && !pos->ops->bind)
 843                         continue;
 844
 845                 if (pos->ops->bind) {
 846                         ret = pos->ops->bind(pos, cdev);
 847                         if (ret)
 848                                 print_bind_err_msg(pos, cdev, ret);
 849                         continue;
 850                 }
 851
 852                 tzp = pos->tzp;
 853                 if (!tzp || !tzp->tbp)
 854                         continue;
 855
 856                 for (i = 0; i < tzp->num_tbps; i++) {
 857                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 858                                 continue;
 859                         if (tzp->tbp[i].match(pos, cdev))
 860                                 continue;
 861                         tzp->tbp[i].cdev = cdev;
 862                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 863                                tzp->tbp[i].binding_limits,
 864                                tzp->tbp[i].weight);
 865                 }
 866         }
 867
 868         mutex_unlock(&thermal_list_lock);
 869 }
 870
 871 /**
 872  * __thermal_cooling_device_register() - register a new thermal cooling device
 873  * @np:         a pointer to a device tree node.
 874  * @type:       the thermal cooling device type.
 875  * @devdata:    device private data.
 876  * @ops:                standard thermal cooling devices callbacks.
 877  *
 878  * This interface function adds a new thermal cooling device (fan/processor/...)
 879  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 880  * to all the thermal zone devices registered at the same time.
 881  * It also gives the opportunity to link the cooling device to a device tree
 882  * node, so that it can be bound to a thermal zone created out of device tree.
 883  *
 884  * Return: a pointer to the created struct thermal_cooling_device or an
 885  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 886  */
 887 static struct thermal_cooling_device *
 888 __thermal_cooling_device_register(struct device_node *np,
 889                                   const char *type, void *devdata,
 890                                   const struct thermal_cooling_device_ops *ops)
 891 {
 892         struct thermal_cooling_device *cdev;
 893         struct thermal_zone_device *pos = NULL;
 894         int id, ret;
 895
 896         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 897             !ops->set_cur_state)
 898                 return ERR_PTR(-EINVAL);
 899
 900         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 901         if (!cdev)
 902                 return ERR_PTR(-ENOMEM);
 903
 904         ret = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 905         if (ret < 0)
 906                 goto out_kfree_cdev;
 907         cdev->id = ret;
 908         id = ret;
 909
 910         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 911         if (ret)
 912                 goto out_ida_remove;
 913
 914         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 915         if (!cdev->type) {
 916                 ret = -ENOMEM;
 917                 goto out_ida_remove;
 918         }
 919
 920         mutex_init(&cdev->lock);
 921         INIT_LIST_HEAD(&cdev->thermal_instances);
 922         cdev->np = np;
 923         cdev->ops = ops;
 924         cdev->updated = false;
 925         cdev->device.class = &thermal_class;
 926         cdev->devdata = devdata;
 927         thermal_cooling_device_setup_sysfs(cdev);
 928         ret = device_register(&cdev->device);
 929         if (ret)
 930                 goto out_kfree_type;
 931
 932         /* Add 'this' new cdev to the global cdev list */
 933         mutex_lock(&thermal_list_lock);
 934         list_add(&cdev->node, &thermal_cdev_list);
 935         mutex_unlock(&thermal_list_lock);
 936
 937         /* Update binding information for 'this' new cdev */
 938         bind_cdev(cdev);
 939
 940         mutex_lock(&thermal_list_lock);
 941         list_for_each_entry(pos, &thermal_tz_list, node)
 942                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 943                         thermal_zone_device_update(pos,
 944                                                    THERMAL_EVENT_UNSPECIFIED);
 945         mutex_unlock(&thermal_list_lock);
 946
 947         return cdev;
 948
 949 out_kfree_type:
 950         thermal_cooling_device_destroy_sysfs(cdev);
 951         kfree(cdev->type);
 952         put_device(&cdev->device);
 953         cdev = NULL;
 954 out_ida_remove:
 955         ida_simple_remove(&thermal_cdev_ida, id);
 956 out_kfree_cdev:
 957         kfree(cdev);
 958         return ERR_PTR(ret);
 959 }
 960
 961 /**
 962  * thermal_cooling_device_register() - register a new thermal cooling device
 963  * @type:       the thermal cooling device type.
 964  * @devdata:    device private data.
 965  * @ops:                standard thermal cooling devices callbacks.
 966  *
 967  * This interface function adds a new thermal cooling device (fan/processor/...)
 968  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 969  * to all the thermal zone devices registered at the same time.
 970  *
 971  * Return: a pointer to the created struct thermal_cooling_device or an
 972  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 973  */
 974 struct thermal_cooling_device *
 975 thermal_cooling_device_register(const char *type, void *devdata,
 976                                 const struct thermal_cooling_device_ops *ops)
 977 {
 978         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 979 }
 980 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 981
 982 /**
 983  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 984  * @np:         a pointer to a device tree node.
 985  * @type:       the thermal cooling device type.
 986  * @devdata:    device private data.
 987  * @ops:                standard thermal cooling devices callbacks.
 988  *
 989  * This function will register a cooling device with device tree node reference.
 990  * This interface function adds a new thermal cooling device (fan/processor/...)
 991  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 992  * to all the thermal zone devices registered at the same time.
 993  *
 994  * Return: a pointer to the created struct thermal_cooling_device or an
 995  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 996  */
 997 struct thermal_cooling_device *
 998 thermal_of_cooling_device_register(struct device_node *np,
 999                                    const char *type, void *devdata,
1000                                    const struct thermal_cooling_device_ops *ops)
1001 {
1002         return __thermal_cooling_device_register(np, type, devdata, ops);
1003 }
1004 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1005
1006 static void thermal_cooling_device_release(struct device *dev, void *res)
1007 {
1008         thermal_cooling_device_unregister(
1009                                 *(struct thermal_cooling_device **)res);
1010 }
1011
1012 /**
1013  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1014  *                                             device
1015  * @dev:        a valid struct device pointer of a sensor device.
1016  * @np:         a pointer to a device tree node.
1017  * @type:       the thermal cooling device type.
1018  * @devdata:    device private data.
1019  * @ops:        standard thermal cooling devices callbacks.
1020  *
1021  * This function will register a cooling device with device tree node reference.
1022  * This interface function adds a new thermal cooling device (fan/processor/...)
1023  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1024  * to all the thermal zone devices registered at the same time.
1025  *
1026  * Return: a pointer to the created struct thermal_cooling_device or an
1027  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1028  */
1029 struct thermal_cooling_device *
1030 devm_thermal_of_cooling_device_register(struct device *dev,
1031                                 struct device_node *np,
1032                                 char *type, void *devdata,
1033                                 const struct thermal_cooling_device_ops *ops)
1034 {
1035         struct thermal_cooling_device **ptr, *tcd;
1036
1037         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1038                            GFP_KERNEL);
1039         if (!ptr)
1040                 return ERR_PTR(-ENOMEM);
1041
1042         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1043         if (IS_ERR(tcd)) {
1044                 devres_free(ptr);
1045                 return tcd;
1046         }
1047
1048         *ptr = tcd;
1049         devres_add(dev, ptr);
1050
1051         return tcd;
1052 }
1053 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1054
1055 static void __unbind(struct thermal_zone_device *tz, int mask,
1056                      struct thermal_cooling_device *cdev)
1057 {
1058         int i;
1059
1060         for (i = 0; i < tz->trips; i++)
1061                 if (mask & (1 << i))
1062                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1063 }
1064
1065 /**
1066  * thermal_cooling_device_unregister - removes a thermal cooling device
1067  * @cdev:       the thermal cooling device to remove.
1068  *
1069  * thermal_cooling_device_unregister() must be called when a registered
1070  * thermal cooling device is no longer needed.
1071  */
1072 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1073 {
1074         int i;
1075         const struct thermal_zone_params *tzp;
1076         struct thermal_zone_device *tz;
1077         struct thermal_cooling_device *pos = NULL;
1078
1079         if (!cdev)
1080                 return;
1081
1082         mutex_lock(&thermal_list_lock);
1083         list_for_each_entry(pos, &thermal_cdev_list, node)
1084                 if (pos == cdev)
1085                         break;
1086         if (pos != cdev) {
1087                 /* thermal cooling device not found */
1088                 mutex_unlock(&thermal_list_lock);
1089                 return;
1090         }
1091         list_del(&cdev->node);
1092
1093         /* Unbind all thermal zones associated with 'this' cdev */
1094         list_for_each_entry(tz, &thermal_tz_list, node) {
1095                 if (tz->ops->unbind) {
1096                         tz->ops->unbind(tz, cdev);
1097                         continue;
1098                 }
1099
1100                 if (!tz->tzp || !tz->tzp->tbp)
1101                         continue;
1102
1103                 tzp = tz->tzp;
1104                 for (i = 0; i < tzp->num_tbps; i++) {
1105                         if (tzp->tbp[i].cdev == cdev) {
1106                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1107                                 tzp->tbp[i].cdev = NULL;
1108                         }
1109                 }
1110         }
1111
1112         mutex_unlock(&thermal_list_lock);
1113
1114         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1115         device_del(&cdev->device);
1116         thermal_cooling_device_destroy_sysfs(cdev);
1117         kfree(cdev->type);
1118         put_device(&cdev->device);
1119 }
1120 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1121
1122 static void bind_tz(struct thermal_zone_device *tz)
1123 {
1124         int i, ret;
1125         struct thermal_cooling_device *pos = NULL;
1126         const struct thermal_zone_params *tzp = tz->tzp;
1127
1128         if (!tzp && !tz->ops->bind)
1129                 return;
1130
1131         mutex_lock(&thermal_list_lock);
1132
1133         /* If there is ops->bind, try to use ops->bind */
1134         if (tz->ops->bind) {
1135                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1136                         ret = tz->ops->bind(tz, pos);
1137                         if (ret)
1138                                 print_bind_err_msg(tz, pos, ret);
1139                 }
1140                 goto exit;
1141         }
1142
1143         if (!tzp || !tzp->tbp)
1144                 goto exit;
1145
1146         list_for_each_entry(pos, &thermal_cdev_list, node) {
1147                 for (i = 0; i < tzp->num_tbps; i++) {
1148                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1149                                 continue;
1150                         if (tzp->tbp[i].match(tz, pos))
1151                                 continue;
1152                         tzp->tbp[i].cdev = pos;
1153                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1154                                tzp->tbp[i].binding_limits,
1155                                tzp->tbp[i].weight);
1156                 }
1157         }
1158 exit:
1159         mutex_unlock(&thermal_list_lock);
1160 }
1161
1162 /**
1163  * thermal_zone_device_register() - register a new thermal zone device
1164  * @type:       the thermal zone device type
1165  * @trips:      the number of trip points the thermal zone support
1166  * @mask:       a bit string indicating the writeablility of trip points
1167  * @devdata:    private device data
1168  * @ops:        standard thermal zone device callbacks
1169  * @tzp:        thermal zone platform parameters
1170  * @passive_delay: number of milliseconds to wait between polls when
1171  *                 performing passive cooling
1172  * @polling_delay: number of milliseconds to wait between polls when checking
1173  *                 whether trip points have been crossed (0 for interrupt
1174  *                 driven systems)
1175  *
1176  * This interface function adds a new thermal zone device (sensor) to
1177  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1178  * thermal cooling devices registered at the same time.
1179  * thermal_zone_device_unregister() must be called when the device is no
1180  * longer needed. The passive cooling depends on the .get_trend() return value.
1181  *
1182  * Return: a pointer to the created struct thermal_zone_device or an
1183  * in case of error, an ERR_PTR. Caller must check return value with
1184  * IS_ERR*() helpers.
1185  */
1186 struct thermal_zone_device *
1187 thermal_zone_device_register(const char *type, int trips, int mask,
1188                              void *devdata, struct thermal_zone_device_ops *ops,
1189                              struct thermal_zone_params *tzp, int passive_delay,
1190                              int polling_delay)
1191 {
1192         struct thermal_zone_device *tz;
1193         enum thermal_trip_type trip_type;
1194         int trip_temp;
1195         int id;
1196         int result;
1197         int count;
1198         struct thermal_governor *governor;
1199
1200         if (!type || strlen(type) == 0) {
1201                 pr_err("Error: No thermal zone type defined\n");
1202                 return ERR_PTR(-EINVAL);
1203         }
1204
1205         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1206                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1207                        type, THERMAL_NAME_LENGTH);
1208                 return ERR_PTR(-EINVAL);
1209         }
1210
1211         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1212                 pr_err("Error: Incorrect number of thermal trips\n");
1213                 return ERR_PTR(-EINVAL);
1214         }
1215
1216         if (!ops) {
1217                 pr_err("Error: Thermal zone device ops not defined\n");
1218                 return ERR_PTR(-EINVAL);
1219         }
1220
1221         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1222                 return ERR_PTR(-EINVAL);
1223
1224         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1225         if (!tz)
1226                 return ERR_PTR(-ENOMEM);
1227
1228         INIT_LIST_HEAD(&tz->thermal_instances);
1229         ida_init(&tz->ida);
1230         mutex_init(&tz->lock);
1231         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1232         if (id < 0) {
1233                 result = id;
1234                 goto free_tz;
1235         }
1236
1237         tz->id = id;
1238         strlcpy(tz->type, type, sizeof(tz->type));
1239
1240         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1241         if (result)
1242                 goto remove_id;
1243
1244         if (!ops->critical)
1245                 ops->critical = thermal_zone_device_critical;
1246
1247         tz->ops = ops;
1248         tz->tzp = tzp;
1249         tz->device.class = &thermal_class;
1250         tz->devdata = devdata;
1251         tz->trips = trips;
1252
1253         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1254         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1255
1256         /* sys I/F */
1257         /* Add nodes that are always present via .groups */
1258         result = thermal_zone_create_device_groups(tz, mask);
1259         if (result)
1260                 goto remove_id;
1261
1262         /* A new thermal zone needs to be updated anyway. */
1263         atomic_set(&tz->need_update, 1);
1264
1265         result = device_register(&tz->device);
1266         if (result)
1267                 goto release_device;
1268
1269         for (count = 0; count < trips; count++) {
1270                 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1271                     tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1272                     !trip_temp)
1273                         set_bit(count, &tz->trips_disabled);
1274         }
1275
1276         /* Update 'this' zone's governor information */
1277         mutex_lock(&thermal_governor_lock);
1278
1279         if (tz->tzp)
1280                 governor = __find_governor(tz->tzp->governor_name);
1281         else
1282                 governor = def_governor;
1283
1284         result = thermal_set_governor(tz, governor);
1285         if (result) {
1286                 mutex_unlock(&thermal_governor_lock);
1287                 goto unregister;
1288         }
1289
1290         mutex_unlock(&thermal_governor_lock);
1291
1292         if (!tz->tzp || !tz->tzp->no_hwmon) {
1293                 result = thermal_add_hwmon_sysfs(tz);
1294                 if (result)
1295                         goto unregister;
1296         }
1297
1298         mutex_lock(&thermal_list_lock);
1299         list_add_tail(&tz->node, &thermal_tz_list);
1300         mutex_unlock(&thermal_list_lock);
1301
1302         /* Bind cooling devices for this zone */
1303         bind_tz(tz);
1304
1305         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1306
1307         thermal_zone_device_init(tz);
1308         /* Update the new thermal zone and mark it as already updated. */
1309         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1310                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1311
1312         thermal_notify_tz_create(tz->id, tz->type);
1313
1314         return tz;
1315
1316 unregister:
1317         device_del(&tz->device);
1318 release_device:
1319         put_device(&tz->device);
1320         tz = NULL;
1321 remove_id:
1322         ida_simple_remove(&thermal_tz_ida, id);
1323 free_tz:
1324         kfree(tz);
1325         return ERR_PTR(result);
1326 }
1327 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1328
1329 /**
1330  * thermal_zone_device_unregister - removes the registered thermal zone device
1331  * @tz: the thermal zone device to remove
1332  */
1333 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1334 {
1335         int i, tz_id;
1336         const struct thermal_zone_params *tzp;
1337         struct thermal_cooling_device *cdev;
1338         struct thermal_zone_device *pos = NULL;
1339
1340         if (!tz)
1341                 return;
1342
1343         tzp = tz->tzp;
1344         tz_id = tz->id;
1345
1346         mutex_lock(&thermal_list_lock);
1347         list_for_each_entry(pos, &thermal_tz_list, node)
1348                 if (pos == tz)
1349                         break;
1350         if (pos != tz) {
1351                 /* thermal zone device not found */
1352                 mutex_unlock(&thermal_list_lock);
1353                 return;
1354         }
1355         list_del(&tz->node);
1356
1357         /* Unbind all cdevs associated with 'this' thermal zone */
1358         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1359                 if (tz->ops->unbind) {
1360                         tz->ops->unbind(tz, cdev);
1361                         continue;
1362                 }
1363
1364                 if (!tzp || !tzp->tbp)
1365                         break;
1366
1367                 for (i = 0; i < tzp->num_tbps; i++) {
1368                         if (tzp->tbp[i].cdev == cdev) {
1369                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1370                                 tzp->tbp[i].cdev = NULL;
1371                         }
1372                 }
1373         }
1374
1375         mutex_unlock(&thermal_list_lock);
1376
1377         cancel_delayed_work_sync(&tz->poll_queue);
1378
1379         thermal_set_governor(tz, NULL);
1380
1381         thermal_remove_hwmon_sysfs(tz);
1382         ida_simple_remove(&thermal_tz_ida, tz->id);
1383         ida_destroy(&tz->ida);
1384         mutex_destroy(&tz->lock);
1385         device_unregister(&tz->device);
1386
1387         thermal_notify_tz_delete(tz_id);
1388 }
1389 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1390
1391 /**
1392  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1393  * @name: thermal zone name to fetch the temperature
1394  *
1395  * When only one zone is found with the passed name, returns a reference to it.
1396  *
1397  * Return: On success returns a reference to an unique thermal zone with
1398  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1399  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1400  */
1401 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1402 {
1403         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1404         unsigned int found = 0;
1405
1406         if (!name)
1407                 goto exit;
1408
1409         mutex_lock(&thermal_list_lock);
1410         list_for_each_entry(pos, &thermal_tz_list, node)
1411                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1412                         found++;
1413                         ref = pos;
1414                 }
1415         mutex_unlock(&thermal_list_lock);
1416
1417         /* nothing has been found, thus an error code for it */
1418         if (found == 0)
1419                 ref = ERR_PTR(-ENODEV);
1420         else if (found > 1)
1421         /* Success only when an unique zone is found */
1422                 ref = ERR_PTR(-EEXIST);
1423
1424 exit:
1425         return ref;
1426 }
1427 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1428
1429 static int thermal_pm_notify(struct notifier_block *nb,
1430                              unsigned long mode, void *_unused)
1431 {
1432         struct thermal_zone_device *tz;
1433
1434         switch (mode) {
1435         case PM_HIBERNATION_PREPARE:
1436         case PM_RESTORE_PREPARE:
1437         case PM_SUSPEND_PREPARE:
1438                 atomic_set(&in_suspend, 1);
1439                 break;
1440         case PM_POST_HIBERNATION:
1441         case PM_POST_RESTORE:
1442         case PM_POST_SUSPEND:
1443                 atomic_set(&in_suspend, 0);
1444                 list_for_each_entry(tz, &thermal_tz_list, node) {
1445                         if (!thermal_zone_device_is_enabled(tz))
1446                                 continue;
1447
1448                         thermal_zone_device_init(tz);
1449                         thermal_zone_device_update(tz,
1450                                                    THERMAL_EVENT_UNSPECIFIED);
1451                 }
1452                 break;
1453         default:
1454                 break;
1455         }
1456         return 0;
1457 }
1458
1459 static struct notifier_block thermal_pm_nb = {
1460         .notifier_call = thermal_pm_notify,
1461 };
1462
1463 static int __init thermal_init(void)
1464 {
1465         int result;
1466
1467         result = thermal_netlink_init();
1468         if (result)
1469                 goto error;
1470
1471         result = thermal_register_governors();
1472         if (result)
1473                 goto error;
1474
1475         result = class_register(&thermal_class);
1476         if (result)
1477                 goto unregister_governors;
1478
1479         result = of_parse_thermal_zones();
1480         if (result)
1481                 goto unregister_class;
1482
1483         result = register_pm_notifier(&thermal_pm_nb);
1484         if (result)
1485                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1486                         result);
1487
1488         return 0;
1489
1490 unregister_class:
1491         class_unregister(&thermal_class);
1492 unregister_governors:
1493         thermal_unregister_governors();
1494 error:
1495         ida_destroy(&thermal_tz_ida);
1496         ida_destroy(&thermal_cdev_ida);
1497         mutex_destroy(&thermal_list_lock);
1498         mutex_destroy(&thermal_governor_lock);
1499         return result;
1500 }
1501 postcore_initcall(thermal_init);