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/module.h>
  13 #include <linux/device.h>
  14 #include <linux/err.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 MODULE_AUTHOR("Zhang Rui");
  31 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  32 MODULE_LICENSE("GPL v2");
  33
  34 static DEFINE_IDA(thermal_tz_ida);
  35 static DEFINE_IDA(thermal_cdev_ida);
  36
  37 static LIST_HEAD(thermal_tz_list);
  38 static LIST_HEAD(thermal_cdev_list);
  39 static LIST_HEAD(thermal_governor_list);
  40
  41 static DEFINE_MUTEX(thermal_list_lock);
  42 static DEFINE_MUTEX(thermal_governor_lock);
  43 static DEFINE_MUTEX(poweroff_lock);
  44
  45 static atomic_t in_suspend;
  46 static bool power_off_triggered;
  47
  48 static struct thermal_governor *def_governor;
  49
  50 /*
  51  * Governor section: set of functions to handle thermal governors
  52  *
  53  * Functions to help in the life cycle of thermal governors within
  54  * the thermal core and by the thermal governor code.
  55  */
  56
  57 static struct thermal_governor *__find_governor(const char *name)
  58 {
  59         struct thermal_governor *pos;
  60
  61         if (!name || !name[0])
  62                 return def_governor;
  63
  64         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  65                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  66                         return pos;
  67
  68         return NULL;
  69 }
  70
  71 /**
  72  * bind_previous_governor() - bind the previous governor of the thermal zone
  73  * @tz:         a valid pointer to a struct thermal_zone_device
  74  * @failed_gov_name:    the name of the governor that failed to register
  75  *
  76  * Register the previous governor of the thermal zone after a new
  77  * governor has failed to be bound.
  78  */
  79 static void bind_previous_governor(struct thermal_zone_device *tz,
  80                                    const char *failed_gov_name)
  81 {
  82         if (tz->governor && tz->governor->bind_to_tz) {
  83                 if (tz->governor->bind_to_tz(tz)) {
  84                         dev_err(&tz->device,
  85                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  86                                 failed_gov_name, tz->governor->name, tz->type);
  87                         tz->governor = NULL;
  88                 }
  89         }
  90 }
  91
  92 /**
  93  * thermal_set_governor() - Switch to another governor
  94  * @tz:         a valid pointer to a struct thermal_zone_device
  95  * @new_gov:    pointer to the new governor
  96  *
  97  * Change the governor of thermal zone @tz.
  98  *
  99  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 100  */
 101 static int thermal_set_governor(struct thermal_zone_device *tz,
 102                                 struct thermal_governor *new_gov)
 103 {
 104         int ret = 0;
 105
 106         if (tz->governor && tz->governor->unbind_from_tz)
 107                 tz->governor->unbind_from_tz(tz);
 108
 109         if (new_gov && new_gov->bind_to_tz) {
 110                 ret = new_gov->bind_to_tz(tz);
 111                 if (ret) {
 112                         bind_previous_governor(tz, new_gov->name);
 113
 114                         return ret;
 115                 }
 116         }
 117
 118         tz->governor = new_gov;
 119
 120         return ret;
 121 }
 122
 123 int thermal_register_governor(struct thermal_governor *governor)
 124 {
 125         int err;
 126         const char *name;
 127         struct thermal_zone_device *pos;
 128
 129         if (!governor)
 130                 return -EINVAL;
 131
 132         mutex_lock(&thermal_governor_lock);
 133
 134         err = -EBUSY;
 135         if (!__find_governor(governor->name)) {
 136                 bool match_default;
 137
 138                 err = 0;
 139                 list_add(&governor->governor_list, &thermal_governor_list);
 140                 match_default = !strncmp(governor->name,
 141                                          DEFAULT_THERMAL_GOVERNOR,
 142                                          THERMAL_NAME_LENGTH);
 143
 144                 if (!def_governor && match_default)
 145                         def_governor = governor;
 146         }
 147
 148         mutex_lock(&thermal_list_lock);
 149
 150         list_for_each_entry(pos, &thermal_tz_list, node) {
 151                 /*
 152                  * only thermal zones with specified tz->tzp->governor_name
 153                  * may run with tz->govenor unset
 154                  */
 155                 if (pos->governor)
 156                         continue;
 157
 158                 name = pos->tzp->governor_name;
 159
 160                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 161                         int ret;
 162
 163                         ret = thermal_set_governor(pos, governor);
 164                         if (ret)
 165                                 dev_err(&pos->device,
 166                                         "Failed to set governor %s for thermal zone %s: %d\n",
 167                                         governor->name, pos->type, ret);
 168                 }
 169         }
 170
 171         mutex_unlock(&thermal_list_lock);
 172         mutex_unlock(&thermal_governor_lock);
 173
 174         return err;
 175 }
 176
 177 void thermal_unregister_governor(struct thermal_governor *governor)
 178 {
 179         struct thermal_zone_device *pos;
 180
 181         if (!governor)
 182                 return;
 183
 184         mutex_lock(&thermal_governor_lock);
 185
 186         if (!__find_governor(governor->name))
 187                 goto exit;
 188
 189         mutex_lock(&thermal_list_lock);
 190
 191         list_for_each_entry(pos, &thermal_tz_list, node) {
 192                 if (!strncasecmp(pos->governor->name, governor->name,
 193                                  THERMAL_NAME_LENGTH))
 194                         thermal_set_governor(pos, NULL);
 195         }
 196
 197         mutex_unlock(&thermal_list_lock);
 198         list_del(&governor->governor_list);
 199 exit:
 200         mutex_unlock(&thermal_governor_lock);
 201 }
 202
 203 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 204                                    char *policy)
 205 {
 206         struct thermal_governor *gov;
 207         int ret = -EINVAL;
 208
 209         mutex_lock(&thermal_governor_lock);
 210         mutex_lock(&tz->lock);
 211
 212         gov = __find_governor(strim(policy));
 213         if (!gov)
 214                 goto exit;
 215
 216         ret = thermal_set_governor(tz, gov);
 217
 218 exit:
 219         mutex_unlock(&tz->lock);
 220         mutex_unlock(&thermal_governor_lock);
 221
 222         return ret;
 223 }
 224
 225 int thermal_build_list_of_policies(char *buf)
 226 {
 227         struct thermal_governor *pos;
 228         ssize_t count = 0;
 229         ssize_t size = PAGE_SIZE;
 230
 231         mutex_lock(&thermal_governor_lock);
 232
 233         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 234                 size = PAGE_SIZE - count;
 235                 count += scnprintf(buf + count, size, "%s ", pos->name);
 236         }
 237         count += scnprintf(buf + count, size, "\n");
 238
 239         mutex_unlock(&thermal_governor_lock);
 240
 241         return count;
 242 }
 243
 244 static void __init thermal_unregister_governors(void)
 245 {
 246         struct thermal_governor **governor;
 247
 248         for_each_governor_table(governor)
 249                 thermal_unregister_governor(*governor);
 250 }
 251
 252 static int __init thermal_register_governors(void)
 253 {
 254         int ret = 0;
 255         struct thermal_governor **governor;
 256
 257         for_each_governor_table(governor) {
 258                 ret = thermal_register_governor(*governor);
 259                 if (ret) {
 260                         pr_err("Failed to register governor: '%s'",
 261                                (*governor)->name);
 262                         break;
 263                 }
 264
 265                 pr_info("Registered thermal governor '%s'",
 266                         (*governor)->name);
 267         }
 268
 269         if (ret) {
 270                 struct thermal_governor **gov;
 271
 272                 for_each_governor_table(gov) {
 273                         if (gov == governor)
 274                                 break;
 275                         thermal_unregister_governor(*gov);
 276                 }
 277         }
 278
 279         return ret;
 280 }
 281
 282 /*
 283  * Zone update section: main control loop applied to each zone while monitoring
 284  *
 285  * in polling mode. The monitoring is done using a workqueue.
 286  * Same update may be done on a zone by calling thermal_zone_device_update().
 287  *
 288  * An update means:
 289  * - Non-critical trips will invoke the governor responsible for that zone;
 290  * - Hot trips will produce a notification to userspace;
 291  * - Critical trip point will cause a system shutdown.
 292  */
 293 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 294                                             int delay)
 295 {
 296         if (delay > 1000)
 297                 mod_delayed_work(system_freezable_power_efficient_wq,
 298                                  &tz->poll_queue,
 299                                  round_jiffies(msecs_to_jiffies(delay)));
 300         else if (delay)
 301                 mod_delayed_work(system_freezable_power_efficient_wq,
 302                                  &tz->poll_queue,
 303                                  msecs_to_jiffies(delay));
 304         else
 305                 cancel_delayed_work(&tz->poll_queue);
 306 }
 307
 308 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 309 {
 310         mutex_lock(&tz->lock);
 311
 312         if (tz->passive)
 313                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 314         else if (tz->polling_delay)
 315                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 316         else
 317                 thermal_zone_device_set_polling(tz, 0);
 318
 319         mutex_unlock(&tz->lock);
 320 }
 321
 322 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 323 {
 324         tz->governor ? tz->governor->throttle(tz, trip) :
 325                        def_governor->throttle(tz, trip);
 326 }
 327
 328 /**
 329  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 330  * @work: work_struct associated with the emergency poweroff function
 331  *
 332  * This function is called in very critical situations to force
 333  * a kernel poweroff after a configurable timeout value.
 334  */
 335 static void thermal_emergency_poweroff_func(struct work_struct *work)
 336 {
 337         /*
 338          * We have reached here after the emergency thermal shutdown
 339          * Waiting period has expired. This means orderly_poweroff has
 340          * not been able to shut off the system for some reason.
 341          * Try to shut down the system immediately using kernel_power_off
 342          * if populated
 343          */
 344         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 345         kernel_power_off();
 346
 347         /*
 348          * Worst of the worst case trigger emergency restart
 349          */
 350         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 351         emergency_restart();
 352 }
 353
 354 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 355                             thermal_emergency_poweroff_func);
 356
 357 /**
 358  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 359  *
 360  * This may be called from any critical situation to trigger a system shutdown
 361  * after a known period of time. By default this is not scheduled.
 362  */
 363 static void thermal_emergency_poweroff(void)
 364 {
 365         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 366         /*
 367          * poweroff_delay_ms must be a carefully profiled positive value.
 368          * Its a must for thermal_emergency_poweroff_work to be scheduled
 369          */
 370         if (poweroff_delay_ms <= 0)
 371                 return;
 372         schedule_delayed_work(&thermal_emergency_poweroff_work,
 373                               msecs_to_jiffies(poweroff_delay_ms));
 374 }
 375
 376 static void handle_critical_trips(struct thermal_zone_device *tz,
 377                                   int trip, enum thermal_trip_type trip_type)
 378 {
 379         int trip_temp;
 380
 381         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 382
 383         /* If we have not crossed the trip_temp, we do not care. */
 384         if (trip_temp <= 0 || tz->temperature < trip_temp)
 385                 return;
 386
 387         trace_thermal_zone_trip(tz, trip, trip_type);
 388
 389         if (tz->ops->notify)
 390                 tz->ops->notify(tz, trip, trip_type);
 391
 392         if (trip_type == THERMAL_TRIP_CRITICAL) {
 393                 dev_emerg(&tz->device,
 394                           "critical temperature reached (%d C), shutting down\n",
 395                           tz->temperature / 1000);
 396                 mutex_lock(&poweroff_lock);
 397                 if (!power_off_triggered) {
 398                         /*
 399                          * Queue a backup emergency shutdown in the event of
 400                          * orderly_poweroff failure
 401                          */
 402                         thermal_emergency_poweroff();
 403                         orderly_poweroff(true);
 404                         power_off_triggered = true;
 405                 }
 406                 mutex_unlock(&poweroff_lock);
 407         }
 408 }
 409
 410 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 411 {
 412         enum thermal_trip_type type;
 413
 414         /* Ignore disabled trip points */
 415         if (test_bit(trip, &tz->trips_disabled))
 416                 return;
 417
 418         tz->ops->get_trip_type(tz, trip, &type);
 419
 420         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 421                 handle_critical_trips(tz, trip, type);
 422         else
 423                 handle_non_critical_trips(tz, trip);
 424         /*
 425          * Alright, we handled this trip successfully.
 426          * So, start monitoring again.
 427          */
 428         monitor_thermal_zone(tz);
 429 }
 430
 431 static void update_temperature(struct thermal_zone_device *tz)
 432 {
 433         int temp, ret;
 434
 435         ret = thermal_zone_get_temp(tz, &temp);
 436         if (ret) {
 437                 if (ret != -EAGAIN)
 438                         dev_warn(&tz->device,
 439                                  "failed to read out thermal zone (%d)\n",
 440                                  ret);
 441                 return;
 442         }
 443
 444         mutex_lock(&tz->lock);
 445         tz->last_temperature = tz->temperature;
 446         tz->temperature = temp;
 447         mutex_unlock(&tz->lock);
 448
 449         trace_thermal_temperature(tz);
 450 }
 451
 452 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 453 {
 454         struct thermal_instance *pos;
 455         tz->temperature = THERMAL_TEMP_INVALID;
 456         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 457                 pos->initialized = false;
 458 }
 459
 460 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 461 {
 462         tz->passive = 0;
 463         thermal_zone_device_init(tz);
 464 }
 465
 466 void thermal_zone_device_update(struct thermal_zone_device *tz,
 467                                 enum thermal_notify_event event)
 468 {
 469         int count;
 470
 471         if (atomic_read(&in_suspend))
 472                 return;
 473
 474         if (!tz->ops->get_temp)
 475                 return;
 476
 477         update_temperature(tz);
 478
 479         thermal_zone_set_trips(tz);
 480
 481         tz->notify_event = event;
 482
 483         for (count = 0; count < tz->trips; count++)
 484                 handle_thermal_trip(tz, count);
 485 }
 486 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 487
 488 /**
 489  * thermal_notify_framework - Sensor drivers use this API to notify framework
 490  * @tz:         thermal zone device
 491  * @trip:       indicates which trip point has been crossed
 492  *
 493  * This function handles the trip events from sensor drivers. It starts
 494  * throttling the cooling devices according to the policy configured.
 495  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 496  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 497  * The throttling policy is based on the configured platform data; if no
 498  * platform data is provided, this uses the step_wise throttling policy.
 499  */
 500 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 501 {
 502         handle_thermal_trip(tz, trip);
 503 }
 504 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 505
 506 static void thermal_zone_device_check(struct work_struct *work)
 507 {
 508         struct thermal_zone_device *tz = container_of(work, struct
 509                                                       thermal_zone_device,
 510                                                       poll_queue.work);
 511         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 512 }
 513
 514 /*
 515  * Power actor section: interface to power actors to estimate power
 516  *
 517  * Set of functions used to interact to cooling devices that know
 518  * how to estimate their devices power consumption.
 519  */
 520
 521 /**
 522  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 523  * @cdev:       pointer to &thermal_cooling_device
 524  * @tz:         a valid thermal zone device pointer
 525  * @max_power:  pointer in which to store the maximum power
 526  *
 527  * Calculate the maximum power consumption in milliwats that the
 528  * cooling device can currently consume and store it in @max_power.
 529  *
 530  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 531  * power_actor API or -E* on other error.
 532  */
 533 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 534                               struct thermal_zone_device *tz, u32 *max_power)
 535 {
 536         if (!cdev_is_power_actor(cdev))
 537                 return -EINVAL;
 538
 539         return cdev->ops->state2power(cdev, tz, 0, max_power);
 540 }
 541
 542 /**
 543  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 544  * @cdev:       pointer to &thermal_cooling_device
 545  * @tz:         a valid thermal zone device pointer
 546  * @min_power:  pointer in which to store the minimum power
 547  *
 548  * Calculate the minimum power consumption in milliwatts that the
 549  * cooling device can currently consume and store it in @min_power.
 550  *
 551  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 552  * power_actor API or -E* on other error.
 553  */
 554 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 555                               struct thermal_zone_device *tz, u32 *min_power)
 556 {
 557         unsigned long max_state;
 558         int ret;
 559
 560         if (!cdev_is_power_actor(cdev))
 561                 return -EINVAL;
 562
 563         ret = cdev->ops->get_max_state(cdev, &max_state);
 564         if (ret)
 565                 return ret;
 566
 567         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 568 }
 569
 570 /**
 571  * power_actor_set_power() - limit the maximum power a cooling device consumes
 572  * @cdev:       pointer to &thermal_cooling_device
 573  * @instance:   thermal instance to update
 574  * @power:      the power in milliwatts
 575  *
 576  * Set the cooling device to consume at most @power milliwatts. The limit is
 577  * expected to be a cap at the maximum power consumption.
 578  *
 579  * Return: 0 on success, -EINVAL if the cooling device does not
 580  * implement the power actor API or -E* for other failures.
 581  */
 582 int power_actor_set_power(struct thermal_cooling_device *cdev,
 583                           struct thermal_instance *instance, u32 power)
 584 {
 585         unsigned long state;
 586         int ret;
 587
 588         if (!cdev_is_power_actor(cdev))
 589                 return -EINVAL;
 590
 591         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 592         if (ret)
 593                 return ret;
 594
 595         instance->target = state;
 596         mutex_lock(&cdev->lock);
 597         cdev->updated = false;
 598         mutex_unlock(&cdev->lock);
 599         thermal_cdev_update(cdev);
 600
 601         return 0;
 602 }
 603
 604 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 605                                           const char *cdev_type, size_t size)
 606 {
 607         struct thermal_cooling_device *cdev = NULL;
 608
 609         mutex_lock(&thermal_list_lock);
 610         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 611                 /* skip non matching cdevs */
 612                 if (strncmp(cdev_type, cdev->type, size))
 613                         continue;
 614
 615                 /* re binding the exception matching the type pattern */
 616                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 617                                                  THERMAL_NO_LIMIT,
 618                                                  THERMAL_NO_LIMIT,
 619                                                  THERMAL_WEIGHT_DEFAULT);
 620         }
 621         mutex_unlock(&thermal_list_lock);
 622 }
 623
 624 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 625                                           const char *cdev_type, size_t size)
 626 {
 627         struct thermal_cooling_device *cdev = NULL;
 628
 629         mutex_lock(&thermal_list_lock);
 630         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 631                 /* skip non matching cdevs */
 632                 if (strncmp(cdev_type, cdev->type, size))
 633                         continue;
 634                 /* unbinding the exception matching the type pattern */
 635                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 636                                                    cdev);
 637         }
 638         mutex_unlock(&thermal_list_lock);
 639 }
 640
 641 /*
 642  * Device management section: cooling devices, zones devices, and binding
 643  *
 644  * Set of functions provided by the thermal core for:
 645  * - cooling devices lifecycle: registration, unregistration,
 646  *                              binding, and unbinding.
 647  * - thermal zone devices lifecycle: registration, unregistration,
 648  *                                   binding, and unbinding.
 649  */
 650
 651 /**
 652  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 653  * @tz:         pointer to struct thermal_zone_device
 654  * @trip:       indicates which trip point the cooling devices is
 655  *              associated with in this thermal zone.
 656  * @cdev:       pointer to struct thermal_cooling_device
 657  * @upper:      the Maximum cooling state for this trip point.
 658  *              THERMAL_NO_LIMIT means no upper limit,
 659  *              and the cooling device can be in max_state.
 660  * @lower:      the Minimum cooling state can be used for this trip point.
 661  *              THERMAL_NO_LIMIT means no lower limit,
 662  *              and the cooling device can be in cooling state 0.
 663  * @weight:     The weight of the cooling device to be bound to the
 664  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 665  *              default value
 666  *
 667  * This interface function bind a thermal cooling device to the certain trip
 668  * point of a thermal zone device.
 669  * This function is usually called in the thermal zone device .bind callback.
 670  *
 671  * Return: 0 on success, the proper error value otherwise.
 672  */
 673 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 674                                      int trip,
 675                                      struct thermal_cooling_device *cdev,
 676                                      unsigned long upper, unsigned long lower,
 677                                      unsigned int weight)
 678 {
 679         struct thermal_instance *dev;
 680         struct thermal_instance *pos;
 681         struct thermal_zone_device *pos1;
 682         struct thermal_cooling_device *pos2;
 683         unsigned long max_state;
 684         int result, ret;
 685
 686         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 687                 return -EINVAL;
 688
 689         list_for_each_entry(pos1, &thermal_tz_list, node) {
 690                 if (pos1 == tz)
 691                         break;
 692         }
 693         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 694                 if (pos2 == cdev)
 695                         break;
 696         }
 697
 698         if (tz != pos1 || cdev != pos2)
 699                 return -EINVAL;
 700
 701         ret = cdev->ops->get_max_state(cdev, &max_state);
 702         if (ret)
 703                 return ret;
 704
 705         /* lower default 0, upper default max_state */
 706         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 707         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 708
 709         if (lower > upper || upper > max_state)
 710                 return -EINVAL;
 711
 712         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 713         if (!dev)
 714                 return -ENOMEM;
 715         dev->tz = tz;
 716         dev->cdev = cdev;
 717         dev->trip = trip;
 718         dev->upper = upper;
 719         dev->lower = lower;
 720         dev->target = THERMAL_NO_TARGET;
 721         dev->weight = weight;
 722
 723         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 724         if (result < 0)
 725                 goto free_mem;
 726
 727         dev->id = result;
 728         sprintf(dev->name, "cdev%d", dev->id);
 729         result =
 730             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 731         if (result)
 732                 goto release_ida;
 733
 734         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 735         sysfs_attr_init(&dev->attr.attr);
 736         dev->attr.attr.name = dev->attr_name;
 737         dev->attr.attr.mode = 0444;
 738         dev->attr.show = trip_point_show;
 739         result = device_create_file(&tz->device, &dev->attr);
 740         if (result)
 741                 goto remove_symbol_link;
 742
 743         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 744         sysfs_attr_init(&dev->weight_attr.attr);
 745         dev->weight_attr.attr.name = dev->weight_attr_name;
 746         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 747         dev->weight_attr.show = weight_show;
 748         dev->weight_attr.store = weight_store;
 749         result = device_create_file(&tz->device, &dev->weight_attr);
 750         if (result)
 751                 goto remove_trip_file;
 752
 753         mutex_lock(&tz->lock);
 754         mutex_lock(&cdev->lock);
 755         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 756                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 757                         result = -EEXIST;
 758                         break;
 759                 }
 760         if (!result) {
 761                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 762                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 763                 atomic_set(&tz->need_update, 1);
 764         }
 765         mutex_unlock(&cdev->lock);
 766         mutex_unlock(&tz->lock);
 767
 768         if (!result)
 769                 return 0;
 770
 771         device_remove_file(&tz->device, &dev->weight_attr);
 772 remove_trip_file:
 773         device_remove_file(&tz->device, &dev->attr);
 774 remove_symbol_link:
 775         sysfs_remove_link(&tz->device.kobj, dev->name);
 776 release_ida:
 777         ida_simple_remove(&tz->ida, dev->id);
 778 free_mem:
 779         kfree(dev);
 780         return result;
 781 }
 782 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 783
 784 /**
 785  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 786  *                                        thermal zone.
 787  * @tz:         pointer to a struct thermal_zone_device.
 788  * @trip:       indicates which trip point the cooling devices is
 789  *              associated with in this thermal zone.
 790  * @cdev:       pointer to a struct thermal_cooling_device.
 791  *
 792  * This interface function unbind a thermal cooling device from the certain
 793  * trip point of a thermal zone device.
 794  * This function is usually called in the thermal zone device .unbind callback.
 795  *
 796  * Return: 0 on success, the proper error value otherwise.
 797  */
 798 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 799                                        int trip,
 800                                        struct thermal_cooling_device *cdev)
 801 {
 802         struct thermal_instance *pos, *next;
 803
 804         mutex_lock(&tz->lock);
 805         mutex_lock(&cdev->lock);
 806         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 807                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 808                         list_del(&pos->tz_node);
 809                         list_del(&pos->cdev_node);
 810                         mutex_unlock(&cdev->lock);
 811                         mutex_unlock(&tz->lock);
 812                         goto unbind;
 813                 }
 814         }
 815         mutex_unlock(&cdev->lock);
 816         mutex_unlock(&tz->lock);
 817
 818         return -ENODEV;
 819
 820 unbind:
 821         device_remove_file(&tz->device, &pos->weight_attr);
 822         device_remove_file(&tz->device, &pos->attr);
 823         sysfs_remove_link(&tz->device.kobj, pos->name);
 824         ida_simple_remove(&tz->ida, pos->id);
 825         kfree(pos);
 826         return 0;
 827 }
 828 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 829
 830 static void thermal_release(struct device *dev)
 831 {
 832         struct thermal_zone_device *tz;
 833         struct thermal_cooling_device *cdev;
 834
 835         if (!strncmp(dev_name(dev), "thermal_zone",
 836                      sizeof("thermal_zone") - 1)) {
 837                 tz = to_thermal_zone(dev);
 838                 thermal_zone_destroy_device_groups(tz);
 839                 kfree(tz);
 840         } else if (!strncmp(dev_name(dev), "cooling_device",
 841                             sizeof("cooling_device") - 1)) {
 842                 cdev = to_cooling_device(dev);
 843                 kfree(cdev);
 844         }
 845 }
 846
 847 static struct class thermal_class = {
 848         .name = "thermal",
 849         .dev_release = thermal_release,
 850 };
 851
 852 static inline
 853 void print_bind_err_msg(struct thermal_zone_device *tz,
 854                         struct thermal_cooling_device *cdev, int ret)
 855 {
 856         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 857                 tz->type, cdev->type, ret);
 858 }
 859
 860 static void __bind(struct thermal_zone_device *tz, int mask,
 861                    struct thermal_cooling_device *cdev,
 862                    unsigned long *limits,
 863                    unsigned int weight)
 864 {
 865         int i, ret;
 866
 867         for (i = 0; i < tz->trips; i++) {
 868                 if (mask & (1 << i)) {
 869                         unsigned long upper, lower;
 870
 871                         upper = THERMAL_NO_LIMIT;
 872                         lower = THERMAL_NO_LIMIT;
 873                         if (limits) {
 874                                 lower = limits[i * 2];
 875                                 upper = limits[i * 2 + 1];
 876                         }
 877                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 878                                                                upper, lower,
 879                                                                weight);
 880                         if (ret)
 881                                 print_bind_err_msg(tz, cdev, ret);
 882                 }
 883         }
 884 }
 885
 886 static void bind_cdev(struct thermal_cooling_device *cdev)
 887 {
 888         int i, ret;
 889         const struct thermal_zone_params *tzp;
 890         struct thermal_zone_device *pos = NULL;
 891
 892         mutex_lock(&thermal_list_lock);
 893
 894         list_for_each_entry(pos, &thermal_tz_list, node) {
 895                 if (!pos->tzp && !pos->ops->bind)
 896                         continue;
 897
 898                 if (pos->ops->bind) {
 899                         ret = pos->ops->bind(pos, cdev);
 900                         if (ret)
 901                                 print_bind_err_msg(pos, cdev, ret);
 902                         continue;
 903                 }
 904
 905                 tzp = pos->tzp;
 906                 if (!tzp || !tzp->tbp)
 907                         continue;
 908
 909                 for (i = 0; i < tzp->num_tbps; i++) {
 910                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 911                                 continue;
 912                         if (tzp->tbp[i].match(pos, cdev))
 913                                 continue;
 914                         tzp->tbp[i].cdev = cdev;
 915                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 916                                tzp->tbp[i].binding_limits,
 917                                tzp->tbp[i].weight);
 918                 }
 919         }
 920
 921         mutex_unlock(&thermal_list_lock);
 922 }
 923
 924 /**
 925  * __thermal_cooling_device_register() - register a new thermal cooling device
 926  * @np:         a pointer to a device tree node.
 927  * @type:       the thermal cooling device type.
 928  * @devdata:    device private data.
 929  * @ops:                standard thermal cooling devices callbacks.
 930  *
 931  * This interface function adds a new thermal cooling device (fan/processor/...)
 932  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 933  * to all the thermal zone devices registered at the same time.
 934  * It also gives the opportunity to link the cooling device to a device tree
 935  * node, so that it can be bound to a thermal zone created out of device tree.
 936  *
 937  * Return: a pointer to the created struct thermal_cooling_device or an
 938  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 939  */
 940 static struct thermal_cooling_device *
 941 __thermal_cooling_device_register(struct device_node *np,
 942                                   const char *type, void *devdata,
 943                                   const struct thermal_cooling_device_ops *ops)
 944 {
 945         struct thermal_cooling_device *cdev;
 946         struct thermal_zone_device *pos = NULL;
 947         int result;
 948
 949         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 950                 return ERR_PTR(-EINVAL);
 951
 952         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 953             !ops->set_cur_state)
 954                 return ERR_PTR(-EINVAL);
 955
 956         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 957         if (!cdev)
 958                 return ERR_PTR(-ENOMEM);
 959
 960         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 961         if (result < 0) {
 962                 kfree(cdev);
 963                 return ERR_PTR(result);
 964         }
 965
 966         cdev->id = result;
 967         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 968         mutex_init(&cdev->lock);
 969         INIT_LIST_HEAD(&cdev->thermal_instances);
 970         cdev->np = np;
 971         cdev->ops = ops;
 972         cdev->updated = false;
 973         cdev->device.class = &thermal_class;
 974         cdev->devdata = devdata;
 975         thermal_cooling_device_setup_sysfs(cdev);
 976         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 977         result = device_register(&cdev->device);
 978         if (result) {
 979                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 980                 put_device(&cdev->device);
 981                 return ERR_PTR(result);
 982         }
 983
 984         /* Add 'this' new cdev to the global cdev list */
 985         mutex_lock(&thermal_list_lock);
 986         list_add(&cdev->node, &thermal_cdev_list);
 987         mutex_unlock(&thermal_list_lock);
 988
 989         /* Update binding information for 'this' new cdev */
 990         bind_cdev(cdev);
 991
 992         mutex_lock(&thermal_list_lock);
 993         list_for_each_entry(pos, &thermal_tz_list, node)
 994                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 995                         thermal_zone_device_update(pos,
 996                                                    THERMAL_EVENT_UNSPECIFIED);
 997         mutex_unlock(&thermal_list_lock);
 998
 999         return cdev;
1000 }
1001
1002 /**
1003  * thermal_cooling_device_register() - register a new thermal cooling device
1004  * @type:       the thermal cooling device type.
1005  * @devdata:    device private data.
1006  * @ops:                standard thermal cooling devices callbacks.
1007  *
1008  * This interface function adds a new thermal cooling device (fan/processor/...)
1009  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1010  * to all the thermal zone devices registered at the same time.
1011  *
1012  * Return: a pointer to the created struct thermal_cooling_device or an
1013  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1014  */
1015 struct thermal_cooling_device *
1016 thermal_cooling_device_register(const char *type, void *devdata,
1017                                 const struct thermal_cooling_device_ops *ops)
1018 {
1019         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1020 }
1021 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1022
1023 /**
1024  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1025  * @np:         a pointer to a device tree node.
1026  * @type:       the thermal cooling device type.
1027  * @devdata:    device private data.
1028  * @ops:                standard thermal cooling devices callbacks.
1029  *
1030  * This function will register a cooling device with device tree node reference.
1031  * This interface function adds a new thermal cooling device (fan/processor/...)
1032  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1033  * to all the thermal zone devices registered at the same time.
1034  *
1035  * Return: a pointer to the created struct thermal_cooling_device or an
1036  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1037  */
1038 struct thermal_cooling_device *
1039 thermal_of_cooling_device_register(struct device_node *np,
1040                                    const char *type, void *devdata,
1041                                    const struct thermal_cooling_device_ops *ops)
1042 {
1043         return __thermal_cooling_device_register(np, type, devdata, ops);
1044 }
1045 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1046
1047 static void thermal_cooling_device_release(struct device *dev, void *res)
1048 {
1049         thermal_cooling_device_unregister(
1050                                 *(struct thermal_cooling_device **)res);
1051 }
1052
1053 /**
1054  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1055  *                                             device
1056  * @dev:        a valid struct device pointer of a sensor device.
1057  * @np:         a pointer to a device tree node.
1058  * @type:       the thermal cooling device type.
1059  * @devdata:    device private data.
1060  * @ops:        standard thermal cooling devices callbacks.
1061  *
1062  * This function will register a cooling device with device tree node reference.
1063  * This interface function adds a new thermal cooling device (fan/processor/...)
1064  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1065  * to all the thermal zone devices registered at the same time.
1066  *
1067  * Return: a pointer to the created struct thermal_cooling_device or an
1068  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1069  */
1070 struct thermal_cooling_device *
1071 devm_thermal_of_cooling_device_register(struct device *dev,
1072                                 struct device_node *np,
1073                                 char *type, void *devdata,
1074                                 const struct thermal_cooling_device_ops *ops)
1075 {
1076         struct thermal_cooling_device **ptr, *tcd;
1077
1078         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1079                            GFP_KERNEL);
1080         if (!ptr)
1081                 return ERR_PTR(-ENOMEM);
1082
1083         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1084         if (IS_ERR(tcd)) {
1085                 devres_free(ptr);
1086                 return tcd;
1087         }
1088
1089         *ptr = tcd;
1090         devres_add(dev, ptr);
1091
1092         return tcd;
1093 }
1094 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1095
1096 static void __unbind(struct thermal_zone_device *tz, int mask,
1097                      struct thermal_cooling_device *cdev)
1098 {
1099         int i;
1100
1101         for (i = 0; i < tz->trips; i++)
1102                 if (mask & (1 << i))
1103                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1104 }
1105
1106 /**
1107  * thermal_cooling_device_unregister - removes a thermal cooling device
1108  * @cdev:       the thermal cooling device to remove.
1109  *
1110  * thermal_cooling_device_unregister() must be called when a registered
1111  * thermal cooling device is no longer needed.
1112  */
1113 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1114 {
1115         int i;
1116         const struct thermal_zone_params *tzp;
1117         struct thermal_zone_device *tz;
1118         struct thermal_cooling_device *pos = NULL;
1119
1120         if (!cdev)
1121                 return;
1122
1123         mutex_lock(&thermal_list_lock);
1124         list_for_each_entry(pos, &thermal_cdev_list, node)
1125                 if (pos == cdev)
1126                         break;
1127         if (pos != cdev) {
1128                 /* thermal cooling device not found */
1129                 mutex_unlock(&thermal_list_lock);
1130                 return;
1131         }
1132         list_del(&cdev->node);
1133
1134         /* Unbind all thermal zones associated with 'this' cdev */
1135         list_for_each_entry(tz, &thermal_tz_list, node) {
1136                 if (tz->ops->unbind) {
1137                         tz->ops->unbind(tz, cdev);
1138                         continue;
1139                 }
1140
1141                 if (!tz->tzp || !tz->tzp->tbp)
1142                         continue;
1143
1144                 tzp = tz->tzp;
1145                 for (i = 0; i < tzp->num_tbps; i++) {
1146                         if (tzp->tbp[i].cdev == cdev) {
1147                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1148                                 tzp->tbp[i].cdev = NULL;
1149                         }
1150                 }
1151         }
1152
1153         mutex_unlock(&thermal_list_lock);
1154
1155         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1156         device_del(&cdev->device);
1157         thermal_cooling_device_destroy_sysfs(cdev);
1158         put_device(&cdev->device);
1159 }
1160 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1161
1162 static void bind_tz(struct thermal_zone_device *tz)
1163 {
1164         int i, ret;
1165         struct thermal_cooling_device *pos = NULL;
1166         const struct thermal_zone_params *tzp = tz->tzp;
1167
1168         if (!tzp && !tz->ops->bind)
1169                 return;
1170
1171         mutex_lock(&thermal_list_lock);
1172
1173         /* If there is ops->bind, try to use ops->bind */
1174         if (tz->ops->bind) {
1175                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1176                         ret = tz->ops->bind(tz, pos);
1177                         if (ret)
1178                                 print_bind_err_msg(tz, pos, ret);
1179                 }
1180                 goto exit;
1181         }
1182
1183         if (!tzp || !tzp->tbp)
1184                 goto exit;
1185
1186         list_for_each_entry(pos, &thermal_cdev_list, node) {
1187                 for (i = 0; i < tzp->num_tbps; i++) {
1188                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1189                                 continue;
1190                         if (tzp->tbp[i].match(tz, pos))
1191                                 continue;
1192                         tzp->tbp[i].cdev = pos;
1193                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1194                                tzp->tbp[i].binding_limits,
1195                                tzp->tbp[i].weight);
1196                 }
1197         }
1198 exit:
1199         mutex_unlock(&thermal_list_lock);
1200 }
1201
1202 /**
1203  * thermal_zone_device_register() - register a new thermal zone device
1204  * @type:       the thermal zone device type
1205  * @trips:      the number of trip points the thermal zone support
1206  * @mask:       a bit string indicating the writeablility of trip points
1207  * @devdata:    private device data
1208  * @ops:        standard thermal zone device callbacks
1209  * @tzp:        thermal zone platform parameters
1210  * @passive_delay: number of milliseconds to wait between polls when
1211  *                 performing passive cooling
1212  * @polling_delay: number of milliseconds to wait between polls when checking
1213  *                 whether trip points have been crossed (0 for interrupt
1214  *                 driven systems)
1215  *
1216  * This interface function adds a new thermal zone device (sensor) to
1217  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1218  * thermal cooling devices registered at the same time.
1219  * thermal_zone_device_unregister() must be called when the device is no
1220  * longer needed. The passive cooling depends on the .get_trend() return value.
1221  *
1222  * Return: a pointer to the created struct thermal_zone_device or an
1223  * in case of error, an ERR_PTR. Caller must check return value with
1224  * IS_ERR*() helpers.
1225  */
1226 struct thermal_zone_device *
1227 thermal_zone_device_register(const char *type, int trips, int mask,
1228                              void *devdata, struct thermal_zone_device_ops *ops,
1229                              struct thermal_zone_params *tzp, int passive_delay,
1230                              int polling_delay)
1231 {
1232         struct thermal_zone_device *tz;
1233         enum thermal_trip_type trip_type;
1234         int trip_temp;
1235         int id;
1236         int result;
1237         int count;
1238         struct thermal_governor *governor;
1239
1240         if (!type || strlen(type) == 0) {
1241                 pr_err("Error: No thermal zone type defined\n");
1242                 return ERR_PTR(-EINVAL);
1243         }
1244
1245         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1246                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1247                        type, THERMAL_NAME_LENGTH);
1248                 return ERR_PTR(-EINVAL);
1249         }
1250
1251         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1252                 pr_err("Error: Incorrect number of thermal trips\n");
1253                 return ERR_PTR(-EINVAL);
1254         }
1255
1256         if (!ops) {
1257                 pr_err("Error: Thermal zone device ops not defined\n");
1258                 return ERR_PTR(-EINVAL);
1259         }
1260
1261         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1262                 return ERR_PTR(-EINVAL);
1263
1264         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1265         if (!tz)
1266                 return ERR_PTR(-ENOMEM);
1267
1268         INIT_LIST_HEAD(&tz->thermal_instances);
1269         ida_init(&tz->ida);
1270         mutex_init(&tz->lock);
1271         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1272         if (id < 0) {
1273                 result = id;
1274                 goto free_tz;
1275         }
1276
1277         tz->id = id;
1278         strlcpy(tz->type, type, sizeof(tz->type));
1279         tz->ops = ops;
1280         tz->tzp = tzp;
1281         tz->device.class = &thermal_class;
1282         tz->devdata = devdata;
1283         tz->trips = trips;
1284         tz->passive_delay = passive_delay;
1285         tz->polling_delay = polling_delay;
1286
1287         /* sys I/F */
1288         /* Add nodes that are always present via .groups */
1289         result = thermal_zone_create_device_groups(tz, mask);
1290         if (result)
1291                 goto remove_id;
1292
1293         /* A new thermal zone needs to be updated anyway. */
1294         atomic_set(&tz->need_update, 1);
1295
1296         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1297         result = device_register(&tz->device);
1298         if (result)
1299                 goto release_device;
1300
1301         for (count = 0; count < trips; count++) {
1302                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1303                         set_bit(count, &tz->trips_disabled);
1304                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1305                         set_bit(count, &tz->trips_disabled);
1306                 /* Check for bogus trip points */
1307                 if (trip_temp == 0)
1308                         set_bit(count, &tz->trips_disabled);
1309         }
1310
1311         /* Update 'this' zone's governor information */
1312         mutex_lock(&thermal_governor_lock);
1313
1314         if (tz->tzp)
1315                 governor = __find_governor(tz->tzp->governor_name);
1316         else
1317                 governor = def_governor;
1318
1319         result = thermal_set_governor(tz, governor);
1320         if (result) {
1321                 mutex_unlock(&thermal_governor_lock);
1322                 goto unregister;
1323         }
1324
1325         mutex_unlock(&thermal_governor_lock);
1326
1327         if (!tz->tzp || !tz->tzp->no_hwmon) {
1328                 result = thermal_add_hwmon_sysfs(tz);
1329                 if (result)
1330                         goto unregister;
1331         }
1332
1333         mutex_lock(&thermal_list_lock);
1334         list_add_tail(&tz->node, &thermal_tz_list);
1335         mutex_unlock(&thermal_list_lock);
1336
1337         /* Bind cooling devices for this zone */
1338         bind_tz(tz);
1339
1340         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1341
1342         thermal_zone_device_reset(tz);
1343         /* Update the new thermal zone and mark it as already updated. */
1344         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1345                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1346
1347         return tz;
1348
1349 unregister:
1350         device_del(&tz->device);
1351 release_device:
1352         put_device(&tz->device);
1353         tz = NULL;
1354 remove_id:
1355         ida_simple_remove(&thermal_tz_ida, id);
1356 free_tz:
1357         kfree(tz);
1358         return ERR_PTR(result);
1359 }
1360 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1361
1362 /**
1363  * thermal_device_unregister - removes the registered thermal zone device
1364  * @tz: the thermal zone device to remove
1365  */
1366 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1367 {
1368         int i;
1369         const struct thermal_zone_params *tzp;
1370         struct thermal_cooling_device *cdev;
1371         struct thermal_zone_device *pos = NULL;
1372
1373         if (!tz)
1374                 return;
1375
1376         tzp = tz->tzp;
1377
1378         mutex_lock(&thermal_list_lock);
1379         list_for_each_entry(pos, &thermal_tz_list, node)
1380                 if (pos == tz)
1381                         break;
1382         if (pos != tz) {
1383                 /* thermal zone device not found */
1384                 mutex_unlock(&thermal_list_lock);
1385                 return;
1386         }
1387         list_del(&tz->node);
1388
1389         /* Unbind all cdevs associated with 'this' thermal zone */
1390         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1391                 if (tz->ops->unbind) {
1392                         tz->ops->unbind(tz, cdev);
1393                         continue;
1394                 }
1395
1396                 if (!tzp || !tzp->tbp)
1397                         break;
1398
1399                 for (i = 0; i < tzp->num_tbps; i++) {
1400                         if (tzp->tbp[i].cdev == cdev) {
1401                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1402                                 tzp->tbp[i].cdev = NULL;
1403                         }
1404                 }
1405         }
1406
1407         mutex_unlock(&thermal_list_lock);
1408
1409         cancel_delayed_work_sync(&tz->poll_queue);
1410
1411         thermal_set_governor(tz, NULL);
1412
1413         thermal_remove_hwmon_sysfs(tz);
1414         ida_simple_remove(&thermal_tz_ida, tz->id);
1415         ida_destroy(&tz->ida);
1416         mutex_destroy(&tz->lock);
1417         device_unregister(&tz->device);
1418 }
1419 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1420
1421 /**
1422  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1423  * @name: thermal zone name to fetch the temperature
1424  *
1425  * When only one zone is found with the passed name, returns a reference to it.
1426  *
1427  * Return: On success returns a reference to an unique thermal zone with
1428  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1429  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1430  */
1431 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1432 {
1433         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1434         unsigned int found = 0;
1435
1436         if (!name)
1437                 goto exit;
1438
1439         mutex_lock(&thermal_list_lock);
1440         list_for_each_entry(pos, &thermal_tz_list, node)
1441                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1442                         found++;
1443                         ref = pos;
1444                 }
1445         mutex_unlock(&thermal_list_lock);
1446
1447         /* nothing has been found, thus an error code for it */
1448         if (found == 0)
1449                 ref = ERR_PTR(-ENODEV);
1450         else if (found > 1)
1451         /* Success only when an unique zone is found */
1452                 ref = ERR_PTR(-EEXIST);
1453
1454 exit:
1455         return ref;
1456 }
1457 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1458
1459 static int thermal_pm_notify(struct notifier_block *nb,
1460                              unsigned long mode, void *_unused)
1461 {
1462         struct thermal_zone_device *tz;
1463         enum thermal_device_mode tz_mode;
1464
1465         switch (mode) {
1466         case PM_HIBERNATION_PREPARE:
1467         case PM_RESTORE_PREPARE:
1468         case PM_SUSPEND_PREPARE:
1469                 atomic_set(&in_suspend, 1);
1470                 break;
1471         case PM_POST_HIBERNATION:
1472         case PM_POST_RESTORE:
1473         case PM_POST_SUSPEND:
1474                 atomic_set(&in_suspend, 0);
1475                 list_for_each_entry(tz, &thermal_tz_list, node) {
1476                         tz_mode = THERMAL_DEVICE_ENABLED;
1477                         if (tz->ops->get_mode)
1478                                 tz->ops->get_mode(tz, &tz_mode);
1479
1480                         if (tz_mode == THERMAL_DEVICE_DISABLED)
1481                                 continue;
1482
1483                         thermal_zone_device_init(tz);
1484                         thermal_zone_device_update(tz,
1485                                                    THERMAL_EVENT_UNSPECIFIED);
1486                 }
1487                 break;
1488         default:
1489                 break;
1490         }
1491         return 0;
1492 }
1493
1494 static struct notifier_block thermal_pm_nb = {
1495         .notifier_call = thermal_pm_notify,
1496 };
1497
1498 static int __init thermal_init(void)
1499 {
1500         int result;
1501
1502         mutex_init(&poweroff_lock);
1503         result = thermal_register_governors();
1504         if (result)
1505                 goto error;
1506
1507         result = class_register(&thermal_class);
1508         if (result)
1509                 goto unregister_governors;
1510
1511         result = of_parse_thermal_zones();
1512         if (result)
1513                 goto unregister_class;
1514
1515         result = register_pm_notifier(&thermal_pm_nb);
1516         if (result)
1517                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1518                         result);
1519
1520         return 0;
1521
1522 unregister_class:
1523         class_unregister(&thermal_class);
1524 unregister_governors:
1525         thermal_unregister_governors();
1526 error:
1527         ida_destroy(&thermal_tz_ida);
1528         ida_destroy(&thermal_cdev_ida);
1529         mutex_destroy(&thermal_list_lock);
1530         mutex_destroy(&thermal_governor_lock);
1531         mutex_destroy(&poweroff_lock);
1532         return result;
1533 }
1534 core_initcall(thermal_init);