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         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 451                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 452                         tz->temperature);
 453         else
 454                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 455                         tz->last_temperature, tz->temperature);
 456 }
 457
 458 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 459 {
 460         struct thermal_instance *pos;
 461         tz->temperature = THERMAL_TEMP_INVALID;
 462         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 463                 pos->initialized = false;
 464 }
 465
 466 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 467 {
 468         tz->passive = 0;
 469         thermal_zone_device_init(tz);
 470 }
 471
 472 void thermal_zone_device_update(struct thermal_zone_device *tz,
 473                                 enum thermal_notify_event event)
 474 {
 475         int count;
 476
 477         if (atomic_read(&in_suspend))
 478                 return;
 479
 480         if (!tz->ops->get_temp)
 481                 return;
 482
 483         update_temperature(tz);
 484
 485         thermal_zone_set_trips(tz);
 486
 487         tz->notify_event = event;
 488
 489         for (count = 0; count < tz->trips; count++)
 490                 handle_thermal_trip(tz, count);
 491 }
 492 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 493
 494 /**
 495  * thermal_notify_framework - Sensor drivers use this API to notify framework
 496  * @tz:         thermal zone device
 497  * @trip:       indicates which trip point has been crossed
 498  *
 499  * This function handles the trip events from sensor drivers. It starts
 500  * throttling the cooling devices according to the policy configured.
 501  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 502  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 503  * The throttling policy is based on the configured platform data; if no
 504  * platform data is provided, this uses the step_wise throttling policy.
 505  */
 506 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 507 {
 508         handle_thermal_trip(tz, trip);
 509 }
 510 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 511
 512 static void thermal_zone_device_check(struct work_struct *work)
 513 {
 514         struct thermal_zone_device *tz = container_of(work, struct
 515                                                       thermal_zone_device,
 516                                                       poll_queue.work);
 517         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 518 }
 519
 520 /*
 521  * Power actor section: interface to power actors to estimate power
 522  *
 523  * Set of functions used to interact to cooling devices that know
 524  * how to estimate their devices power consumption.
 525  */
 526
 527 /**
 528  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 529  * @cdev:       pointer to &thermal_cooling_device
 530  * @tz:         a valid thermal zone device pointer
 531  * @max_power:  pointer in which to store the maximum power
 532  *
 533  * Calculate the maximum power consumption in milliwats that the
 534  * cooling device can currently consume and store it in @max_power.
 535  *
 536  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 537  * power_actor API or -E* on other error.
 538  */
 539 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 540                               struct thermal_zone_device *tz, u32 *max_power)
 541 {
 542         if (!cdev_is_power_actor(cdev))
 543                 return -EINVAL;
 544
 545         return cdev->ops->state2power(cdev, tz, 0, max_power);
 546 }
 547
 548 /**
 549  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 550  * @cdev:       pointer to &thermal_cooling_device
 551  * @tz:         a valid thermal zone device pointer
 552  * @min_power:  pointer in which to store the minimum power
 553  *
 554  * Calculate the minimum power consumption in milliwatts that the
 555  * cooling device can currently consume and store it in @min_power.
 556  *
 557  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 558  * power_actor API or -E* on other error.
 559  */
 560 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 561                               struct thermal_zone_device *tz, u32 *min_power)
 562 {
 563         unsigned long max_state;
 564         int ret;
 565
 566         if (!cdev_is_power_actor(cdev))
 567                 return -EINVAL;
 568
 569         ret = cdev->ops->get_max_state(cdev, &max_state);
 570         if (ret)
 571                 return ret;
 572
 573         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 574 }
 575
 576 /**
 577  * power_actor_set_power() - limit the maximum power a cooling device consumes
 578  * @cdev:       pointer to &thermal_cooling_device
 579  * @instance:   thermal instance to update
 580  * @power:      the power in milliwatts
 581  *
 582  * Set the cooling device to consume at most @power milliwatts. The limit is
 583  * expected to be a cap at the maximum power consumption.
 584  *
 585  * Return: 0 on success, -EINVAL if the cooling device does not
 586  * implement the power actor API or -E* for other failures.
 587  */
 588 int power_actor_set_power(struct thermal_cooling_device *cdev,
 589                           struct thermal_instance *instance, u32 power)
 590 {
 591         unsigned long state;
 592         int ret;
 593
 594         if (!cdev_is_power_actor(cdev))
 595                 return -EINVAL;
 596
 597         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 598         if (ret)
 599                 return ret;
 600
 601         instance->target = state;
 602         mutex_lock(&cdev->lock);
 603         cdev->updated = false;
 604         mutex_unlock(&cdev->lock);
 605         thermal_cdev_update(cdev);
 606
 607         return 0;
 608 }
 609
 610 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 611                                           const char *cdev_type, size_t size)
 612 {
 613         struct thermal_cooling_device *cdev = NULL;
 614
 615         mutex_lock(&thermal_list_lock);
 616         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 617                 /* skip non matching cdevs */
 618                 if (strncmp(cdev_type, cdev->type, size))
 619                         continue;
 620
 621                 /* re binding the exception matching the type pattern */
 622                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 623                                                  THERMAL_NO_LIMIT,
 624                                                  THERMAL_NO_LIMIT,
 625                                                  THERMAL_WEIGHT_DEFAULT);
 626         }
 627         mutex_unlock(&thermal_list_lock);
 628 }
 629
 630 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 631                                           const char *cdev_type, size_t size)
 632 {
 633         struct thermal_cooling_device *cdev = NULL;
 634
 635         mutex_lock(&thermal_list_lock);
 636         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 637                 /* skip non matching cdevs */
 638                 if (strncmp(cdev_type, cdev->type, size))
 639                         continue;
 640                 /* unbinding the exception matching the type pattern */
 641                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 642                                                    cdev);
 643         }
 644         mutex_unlock(&thermal_list_lock);
 645 }
 646
 647 /*
 648  * Device management section: cooling devices, zones devices, and binding
 649  *
 650  * Set of functions provided by the thermal core for:
 651  * - cooling devices lifecycle: registration, unregistration,
 652  *                              binding, and unbinding.
 653  * - thermal zone devices lifecycle: registration, unregistration,
 654  *                                   binding, and unbinding.
 655  */
 656
 657 /**
 658  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 659  * @tz:         pointer to struct thermal_zone_device
 660  * @trip:       indicates which trip point the cooling devices is
 661  *              associated with in this thermal zone.
 662  * @cdev:       pointer to struct thermal_cooling_device
 663  * @upper:      the Maximum cooling state for this trip point.
 664  *              THERMAL_NO_LIMIT means no upper limit,
 665  *              and the cooling device can be in max_state.
 666  * @lower:      the Minimum cooling state can be used for this trip point.
 667  *              THERMAL_NO_LIMIT means no lower limit,
 668  *              and the cooling device can be in cooling state 0.
 669  * @weight:     The weight of the cooling device to be bound to the
 670  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 671  *              default value
 672  *
 673  * This interface function bind a thermal cooling device to the certain trip
 674  * point of a thermal zone device.
 675  * This function is usually called in the thermal zone device .bind callback.
 676  *
 677  * Return: 0 on success, the proper error value otherwise.
 678  */
 679 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 680                                      int trip,
 681                                      struct thermal_cooling_device *cdev,
 682                                      unsigned long upper, unsigned long lower,
 683                                      unsigned int weight)
 684 {
 685         struct thermal_instance *dev;
 686         struct thermal_instance *pos;
 687         struct thermal_zone_device *pos1;
 688         struct thermal_cooling_device *pos2;
 689         unsigned long max_state;
 690         int result, ret;
 691
 692         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 693                 return -EINVAL;
 694
 695         list_for_each_entry(pos1, &thermal_tz_list, node) {
 696                 if (pos1 == tz)
 697                         break;
 698         }
 699         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 700                 if (pos2 == cdev)
 701                         break;
 702         }
 703
 704         if (tz != pos1 || cdev != pos2)
 705                 return -EINVAL;
 706
 707         ret = cdev->ops->get_max_state(cdev, &max_state);
 708         if (ret)
 709                 return ret;
 710
 711         /* lower default 0, upper default max_state */
 712         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 713         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 714
 715         if (lower > upper || upper > max_state)
 716                 return -EINVAL;
 717
 718         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 719         if (!dev)
 720                 return -ENOMEM;
 721         dev->tz = tz;
 722         dev->cdev = cdev;
 723         dev->trip = trip;
 724         dev->upper = upper;
 725         dev->lower = lower;
 726         dev->target = THERMAL_NO_TARGET;
 727         dev->weight = weight;
 728
 729         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 730         if (result < 0)
 731                 goto free_mem;
 732
 733         dev->id = result;
 734         sprintf(dev->name, "cdev%d", dev->id);
 735         result =
 736             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 737         if (result)
 738                 goto release_ida;
 739
 740         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 741         sysfs_attr_init(&dev->attr.attr);
 742         dev->attr.attr.name = dev->attr_name;
 743         dev->attr.attr.mode = 0444;
 744         dev->attr.show = trip_point_show;
 745         result = device_create_file(&tz->device, &dev->attr);
 746         if (result)
 747                 goto remove_symbol_link;
 748
 749         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 750         sysfs_attr_init(&dev->weight_attr.attr);
 751         dev->weight_attr.attr.name = dev->weight_attr_name;
 752         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 753         dev->weight_attr.show = weight_show;
 754         dev->weight_attr.store = weight_store;
 755         result = device_create_file(&tz->device, &dev->weight_attr);
 756         if (result)
 757                 goto remove_trip_file;
 758
 759         mutex_lock(&tz->lock);
 760         mutex_lock(&cdev->lock);
 761         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 762                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 763                         result = -EEXIST;
 764                         break;
 765                 }
 766         if (!result) {
 767                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 768                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 769                 atomic_set(&tz->need_update, 1);
 770         }
 771         mutex_unlock(&cdev->lock);
 772         mutex_unlock(&tz->lock);
 773
 774         if (!result)
 775                 return 0;
 776
 777         device_remove_file(&tz->device, &dev->weight_attr);
 778 remove_trip_file:
 779         device_remove_file(&tz->device, &dev->attr);
 780 remove_symbol_link:
 781         sysfs_remove_link(&tz->device.kobj, dev->name);
 782 release_ida:
 783         ida_simple_remove(&tz->ida, dev->id);
 784 free_mem:
 785         kfree(dev);
 786         return result;
 787 }
 788 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 789
 790 /**
 791  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 792  *                                        thermal zone.
 793  * @tz:         pointer to a struct thermal_zone_device.
 794  * @trip:       indicates which trip point the cooling devices is
 795  *              associated with in this thermal zone.
 796  * @cdev:       pointer to a struct thermal_cooling_device.
 797  *
 798  * This interface function unbind a thermal cooling device from the certain
 799  * trip point of a thermal zone device.
 800  * This function is usually called in the thermal zone device .unbind callback.
 801  *
 802  * Return: 0 on success, the proper error value otherwise.
 803  */
 804 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 805                                        int trip,
 806                                        struct thermal_cooling_device *cdev)
 807 {
 808         struct thermal_instance *pos, *next;
 809
 810         mutex_lock(&tz->lock);
 811         mutex_lock(&cdev->lock);
 812         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 813                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 814                         list_del(&pos->tz_node);
 815                         list_del(&pos->cdev_node);
 816                         mutex_unlock(&cdev->lock);
 817                         mutex_unlock(&tz->lock);
 818                         goto unbind;
 819                 }
 820         }
 821         mutex_unlock(&cdev->lock);
 822         mutex_unlock(&tz->lock);
 823
 824         return -ENODEV;
 825
 826 unbind:
 827         device_remove_file(&tz->device, &pos->weight_attr);
 828         device_remove_file(&tz->device, &pos->attr);
 829         sysfs_remove_link(&tz->device.kobj, pos->name);
 830         ida_simple_remove(&tz->ida, pos->id);
 831         kfree(pos);
 832         return 0;
 833 }
 834 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 835
 836 static void thermal_release(struct device *dev)
 837 {
 838         struct thermal_zone_device *tz;
 839         struct thermal_cooling_device *cdev;
 840
 841         if (!strncmp(dev_name(dev), "thermal_zone",
 842                      sizeof("thermal_zone") - 1)) {
 843                 tz = to_thermal_zone(dev);
 844                 thermal_zone_destroy_device_groups(tz);
 845                 kfree(tz);
 846         } else if (!strncmp(dev_name(dev), "cooling_device",
 847                             sizeof("cooling_device") - 1)) {
 848                 cdev = to_cooling_device(dev);
 849                 kfree(cdev);
 850         }
 851 }
 852
 853 static struct class thermal_class = {
 854         .name = "thermal",
 855         .dev_release = thermal_release,
 856 };
 857
 858 static inline
 859 void print_bind_err_msg(struct thermal_zone_device *tz,
 860                         struct thermal_cooling_device *cdev, int ret)
 861 {
 862         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 863                 tz->type, cdev->type, ret);
 864 }
 865
 866 static void __bind(struct thermal_zone_device *tz, int mask,
 867                    struct thermal_cooling_device *cdev,
 868                    unsigned long *limits,
 869                    unsigned int weight)
 870 {
 871         int i, ret;
 872
 873         for (i = 0; i < tz->trips; i++) {
 874                 if (mask & (1 << i)) {
 875                         unsigned long upper, lower;
 876
 877                         upper = THERMAL_NO_LIMIT;
 878                         lower = THERMAL_NO_LIMIT;
 879                         if (limits) {
 880                                 lower = limits[i * 2];
 881                                 upper = limits[i * 2 + 1];
 882                         }
 883                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 884                                                                upper, lower,
 885                                                                weight);
 886                         if (ret)
 887                                 print_bind_err_msg(tz, cdev, ret);
 888                 }
 889         }
 890 }
 891
 892 static void bind_cdev(struct thermal_cooling_device *cdev)
 893 {
 894         int i, ret;
 895         const struct thermal_zone_params *tzp;
 896         struct thermal_zone_device *pos = NULL;
 897
 898         mutex_lock(&thermal_list_lock);
 899
 900         list_for_each_entry(pos, &thermal_tz_list, node) {
 901                 if (!pos->tzp && !pos->ops->bind)
 902                         continue;
 903
 904                 if (pos->ops->bind) {
 905                         ret = pos->ops->bind(pos, cdev);
 906                         if (ret)
 907                                 print_bind_err_msg(pos, cdev, ret);
 908                         continue;
 909                 }
 910
 911                 tzp = pos->tzp;
 912                 if (!tzp || !tzp->tbp)
 913                         continue;
 914
 915                 for (i = 0; i < tzp->num_tbps; i++) {
 916                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 917                                 continue;
 918                         if (tzp->tbp[i].match(pos, cdev))
 919                                 continue;
 920                         tzp->tbp[i].cdev = cdev;
 921                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 922                                tzp->tbp[i].binding_limits,
 923                                tzp->tbp[i].weight);
 924                 }
 925         }
 926
 927         mutex_unlock(&thermal_list_lock);
 928 }
 929
 930 /**
 931  * __thermal_cooling_device_register() - register a new thermal cooling device
 932  * @np:         a pointer to a device tree node.
 933  * @type:       the thermal cooling device type.
 934  * @devdata:    device private data.
 935  * @ops:                standard thermal cooling devices callbacks.
 936  *
 937  * This interface function adds a new thermal cooling device (fan/processor/...)
 938  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 939  * to all the thermal zone devices registered at the same time.
 940  * It also gives the opportunity to link the cooling device to a device tree
 941  * node, so that it can be bound to a thermal zone created out of device tree.
 942  *
 943  * Return: a pointer to the created struct thermal_cooling_device or an
 944  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 945  */
 946 static struct thermal_cooling_device *
 947 __thermal_cooling_device_register(struct device_node *np,
 948                                   const char *type, void *devdata,
 949                                   const struct thermal_cooling_device_ops *ops)
 950 {
 951         struct thermal_cooling_device *cdev;
 952         struct thermal_zone_device *pos = NULL;
 953         int result;
 954
 955         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 956                 return ERR_PTR(-EINVAL);
 957
 958         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 959             !ops->set_cur_state)
 960                 return ERR_PTR(-EINVAL);
 961
 962         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 963         if (!cdev)
 964                 return ERR_PTR(-ENOMEM);
 965
 966         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 967         if (result < 0) {
 968                 kfree(cdev);
 969                 return ERR_PTR(result);
 970         }
 971
 972         cdev->id = result;
 973         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 974         mutex_init(&cdev->lock);
 975         INIT_LIST_HEAD(&cdev->thermal_instances);
 976         cdev->np = np;
 977         cdev->ops = ops;
 978         cdev->updated = false;
 979         cdev->device.class = &thermal_class;
 980         cdev->devdata = devdata;
 981         thermal_cooling_device_setup_sysfs(cdev);
 982         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 983         result = device_register(&cdev->device);
 984         if (result) {
 985                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 986                 put_device(&cdev->device);
 987                 return ERR_PTR(result);
 988         }
 989
 990         /* Add 'this' new cdev to the global cdev list */
 991         mutex_lock(&thermal_list_lock);
 992         list_add(&cdev->node, &thermal_cdev_list);
 993         mutex_unlock(&thermal_list_lock);
 994
 995         /* Update binding information for 'this' new cdev */
 996         bind_cdev(cdev);
 997
 998         mutex_lock(&thermal_list_lock);
 999         list_for_each_entry(pos, &thermal_tz_list, node)
1000                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1001                         thermal_zone_device_update(pos,
1002                                                    THERMAL_EVENT_UNSPECIFIED);
1003         mutex_unlock(&thermal_list_lock);
1004
1005         return cdev;
1006 }
1007
1008 /**
1009  * thermal_cooling_device_register() - register a new thermal cooling device
1010  * @type:       the thermal cooling device type.
1011  * @devdata:    device private data.
1012  * @ops:                standard thermal cooling devices callbacks.
1013  *
1014  * This interface function adds a new thermal cooling device (fan/processor/...)
1015  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1016  * to all the thermal zone devices registered at the same time.
1017  *
1018  * Return: a pointer to the created struct thermal_cooling_device or an
1019  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1020  */
1021 struct thermal_cooling_device *
1022 thermal_cooling_device_register(const char *type, void *devdata,
1023                                 const struct thermal_cooling_device_ops *ops)
1024 {
1025         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1026 }
1027 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1028
1029 /**
1030  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1031  * @np:         a pointer to a device tree node.
1032  * @type:       the thermal cooling device type.
1033  * @devdata:    device private data.
1034  * @ops:                standard thermal cooling devices callbacks.
1035  *
1036  * This function will register a cooling device with device tree node reference.
1037  * This interface function adds a new thermal cooling device (fan/processor/...)
1038  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1039  * to all the thermal zone devices registered at the same time.
1040  *
1041  * Return: a pointer to the created struct thermal_cooling_device or an
1042  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1043  */
1044 struct thermal_cooling_device *
1045 thermal_of_cooling_device_register(struct device_node *np,
1046                                    const char *type, void *devdata,
1047                                    const struct thermal_cooling_device_ops *ops)
1048 {
1049         return __thermal_cooling_device_register(np, type, devdata, ops);
1050 }
1051 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1052
1053 static void thermal_cooling_device_release(struct device *dev, void *res)
1054 {
1055         thermal_cooling_device_unregister(
1056                                 *(struct thermal_cooling_device **)res);
1057 }
1058
1059 /**
1060  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1061  *                                             device
1062  * @dev:        a valid struct device pointer of a sensor device.
1063  * @np:         a pointer to a device tree node.
1064  * @type:       the thermal cooling device type.
1065  * @devdata:    device private data.
1066  * @ops:        standard thermal cooling devices callbacks.
1067  *
1068  * This function will register a cooling device with device tree node reference.
1069  * This interface function adds a new thermal cooling device (fan/processor/...)
1070  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1071  * to all the thermal zone devices registered at the same time.
1072  *
1073  * Return: a pointer to the created struct thermal_cooling_device or an
1074  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1075  */
1076 struct thermal_cooling_device *
1077 devm_thermal_of_cooling_device_register(struct device *dev,
1078                                 struct device_node *np,
1079                                 char *type, void *devdata,
1080                                 const struct thermal_cooling_device_ops *ops)
1081 {
1082         struct thermal_cooling_device **ptr, *tcd;
1083
1084         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1085                            GFP_KERNEL);
1086         if (!ptr)
1087                 return ERR_PTR(-ENOMEM);
1088
1089         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1090         if (IS_ERR(tcd)) {
1091                 devres_free(ptr);
1092                 return tcd;
1093         }
1094
1095         *ptr = tcd;
1096         devres_add(dev, ptr);
1097
1098         return tcd;
1099 }
1100 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1101
1102 static void __unbind(struct thermal_zone_device *tz, int mask,
1103                      struct thermal_cooling_device *cdev)
1104 {
1105         int i;
1106
1107         for (i = 0; i < tz->trips; i++)
1108                 if (mask & (1 << i))
1109                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1110 }
1111
1112 /**
1113  * thermal_cooling_device_unregister - removes a thermal cooling device
1114  * @cdev:       the thermal cooling device to remove.
1115  *
1116  * thermal_cooling_device_unregister() must be called when a registered
1117  * thermal cooling device is no longer needed.
1118  */
1119 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1120 {
1121         int i;
1122         const struct thermal_zone_params *tzp;
1123         struct thermal_zone_device *tz;
1124         struct thermal_cooling_device *pos = NULL;
1125
1126         if (!cdev)
1127                 return;
1128
1129         mutex_lock(&thermal_list_lock);
1130         list_for_each_entry(pos, &thermal_cdev_list, node)
1131                 if (pos == cdev)
1132                         break;
1133         if (pos != cdev) {
1134                 /* thermal cooling device not found */
1135                 mutex_unlock(&thermal_list_lock);
1136                 return;
1137         }
1138         list_del(&cdev->node);
1139
1140         /* Unbind all thermal zones associated with 'this' cdev */
1141         list_for_each_entry(tz, &thermal_tz_list, node) {
1142                 if (tz->ops->unbind) {
1143                         tz->ops->unbind(tz, cdev);
1144                         continue;
1145                 }
1146
1147                 if (!tz->tzp || !tz->tzp->tbp)
1148                         continue;
1149
1150                 tzp = tz->tzp;
1151                 for (i = 0; i < tzp->num_tbps; i++) {
1152                         if (tzp->tbp[i].cdev == cdev) {
1153                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1154                                 tzp->tbp[i].cdev = NULL;
1155                         }
1156                 }
1157         }
1158
1159         mutex_unlock(&thermal_list_lock);
1160
1161         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1162         device_del(&cdev->device);
1163         thermal_cooling_device_destroy_sysfs(cdev);
1164         put_device(&cdev->device);
1165 }
1166 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1167
1168 static void bind_tz(struct thermal_zone_device *tz)
1169 {
1170         int i, ret;
1171         struct thermal_cooling_device *pos = NULL;
1172         const struct thermal_zone_params *tzp = tz->tzp;
1173
1174         if (!tzp && !tz->ops->bind)
1175                 return;
1176
1177         mutex_lock(&thermal_list_lock);
1178
1179         /* If there is ops->bind, try to use ops->bind */
1180         if (tz->ops->bind) {
1181                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1182                         ret = tz->ops->bind(tz, pos);
1183                         if (ret)
1184                                 print_bind_err_msg(tz, pos, ret);
1185                 }
1186                 goto exit;
1187         }
1188
1189         if (!tzp || !tzp->tbp)
1190                 goto exit;
1191
1192         list_for_each_entry(pos, &thermal_cdev_list, node) {
1193                 for (i = 0; i < tzp->num_tbps; i++) {
1194                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1195                                 continue;
1196                         if (tzp->tbp[i].match(tz, pos))
1197                                 continue;
1198                         tzp->tbp[i].cdev = pos;
1199                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1200                                tzp->tbp[i].binding_limits,
1201                                tzp->tbp[i].weight);
1202                 }
1203         }
1204 exit:
1205         mutex_unlock(&thermal_list_lock);
1206 }
1207
1208 /**
1209  * thermal_zone_device_register() - register a new thermal zone device
1210  * @type:       the thermal zone device type
1211  * @trips:      the number of trip points the thermal zone support
1212  * @mask:       a bit string indicating the writeablility of trip points
1213  * @devdata:    private device data
1214  * @ops:        standard thermal zone device callbacks
1215  * @tzp:        thermal zone platform parameters
1216  * @passive_delay: number of milliseconds to wait between polls when
1217  *                 performing passive cooling
1218  * @polling_delay: number of milliseconds to wait between polls when checking
1219  *                 whether trip points have been crossed (0 for interrupt
1220  *                 driven systems)
1221  *
1222  * This interface function adds a new thermal zone device (sensor) to
1223  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1224  * thermal cooling devices registered at the same time.
1225  * thermal_zone_device_unregister() must be called when the device is no
1226  * longer needed. The passive cooling depends on the .get_trend() return value.
1227  *
1228  * Return: a pointer to the created struct thermal_zone_device or an
1229  * in case of error, an ERR_PTR. Caller must check return value with
1230  * IS_ERR*() helpers.
1231  */
1232 struct thermal_zone_device *
1233 thermal_zone_device_register(const char *type, int trips, int mask,
1234                              void *devdata, struct thermal_zone_device_ops *ops,
1235                              struct thermal_zone_params *tzp, int passive_delay,
1236                              int polling_delay)
1237 {
1238         struct thermal_zone_device *tz;
1239         enum thermal_trip_type trip_type;
1240         int trip_temp;
1241         int id;
1242         int result;
1243         int count;
1244         struct thermal_governor *governor;
1245
1246         if (!type || strlen(type) == 0) {
1247                 pr_err("Error: No thermal zone type defined\n");
1248                 return ERR_PTR(-EINVAL);
1249         }
1250
1251         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1252                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1253                        type, THERMAL_NAME_LENGTH);
1254                 return ERR_PTR(-EINVAL);
1255         }
1256
1257         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1258                 pr_err("Error: Incorrect number of thermal trips\n");
1259                 return ERR_PTR(-EINVAL);
1260         }
1261
1262         if (!ops) {
1263                 pr_err("Error: Thermal zone device ops not defined\n");
1264                 return ERR_PTR(-EINVAL);
1265         }
1266
1267         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1268                 return ERR_PTR(-EINVAL);
1269
1270         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1271         if (!tz)
1272                 return ERR_PTR(-ENOMEM);
1273
1274         INIT_LIST_HEAD(&tz->thermal_instances);
1275         ida_init(&tz->ida);
1276         mutex_init(&tz->lock);
1277         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1278         if (id < 0) {
1279                 result = id;
1280                 goto free_tz;
1281         }
1282
1283         tz->id = id;
1284         strlcpy(tz->type, type, sizeof(tz->type));
1285         tz->ops = ops;
1286         tz->tzp = tzp;
1287         tz->device.class = &thermal_class;
1288         tz->devdata = devdata;
1289         tz->trips = trips;
1290         tz->passive_delay = passive_delay;
1291         tz->polling_delay = polling_delay;
1292
1293         /* sys I/F */
1294         /* Add nodes that are always present via .groups */
1295         result = thermal_zone_create_device_groups(tz, mask);
1296         if (result)
1297                 goto remove_id;
1298
1299         /* A new thermal zone needs to be updated anyway. */
1300         atomic_set(&tz->need_update, 1);
1301
1302         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1303         result = device_register(&tz->device);
1304         if (result)
1305                 goto release_device;
1306
1307         for (count = 0; count < trips; count++) {
1308                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1309                         set_bit(count, &tz->trips_disabled);
1310                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1311                         set_bit(count, &tz->trips_disabled);
1312                 /* Check for bogus trip points */
1313                 if (trip_temp == 0)
1314                         set_bit(count, &tz->trips_disabled);
1315         }
1316
1317         /* Update 'this' zone's governor information */
1318         mutex_lock(&thermal_governor_lock);
1319
1320         if (tz->tzp)
1321                 governor = __find_governor(tz->tzp->governor_name);
1322         else
1323                 governor = def_governor;
1324
1325         result = thermal_set_governor(tz, governor);
1326         if (result) {
1327                 mutex_unlock(&thermal_governor_lock);
1328                 goto unregister;
1329         }
1330
1331         mutex_unlock(&thermal_governor_lock);
1332
1333         if (!tz->tzp || !tz->tzp->no_hwmon) {
1334                 result = thermal_add_hwmon_sysfs(tz);
1335                 if (result)
1336                         goto unregister;
1337         }
1338
1339         mutex_lock(&thermal_list_lock);
1340         list_add_tail(&tz->node, &thermal_tz_list);
1341         mutex_unlock(&thermal_list_lock);
1342
1343         /* Bind cooling devices for this zone */
1344         bind_tz(tz);
1345
1346         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1347
1348         thermal_zone_device_reset(tz);
1349         /* Update the new thermal zone and mark it as already updated. */
1350         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1351                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1352
1353         return tz;
1354
1355 unregister:
1356         device_del(&tz->device);
1357 release_device:
1358         put_device(&tz->device);
1359         tz = NULL;
1360 remove_id:
1361         ida_simple_remove(&thermal_tz_ida, id);
1362 free_tz:
1363         kfree(tz);
1364         return ERR_PTR(result);
1365 }
1366 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1367
1368 /**
1369  * thermal_device_unregister - removes the registered thermal zone device
1370  * @tz: the thermal zone device to remove
1371  */
1372 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1373 {
1374         int i;
1375         const struct thermal_zone_params *tzp;
1376         struct thermal_cooling_device *cdev;
1377         struct thermal_zone_device *pos = NULL;
1378
1379         if (!tz)
1380                 return;
1381
1382         tzp = tz->tzp;
1383
1384         mutex_lock(&thermal_list_lock);
1385         list_for_each_entry(pos, &thermal_tz_list, node)
1386                 if (pos == tz)
1387                         break;
1388         if (pos != tz) {
1389                 /* thermal zone device not found */
1390                 mutex_unlock(&thermal_list_lock);
1391                 return;
1392         }
1393         list_del(&tz->node);
1394
1395         /* Unbind all cdevs associated with 'this' thermal zone */
1396         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1397                 if (tz->ops->unbind) {
1398                         tz->ops->unbind(tz, cdev);
1399                         continue;
1400                 }
1401
1402                 if (!tzp || !tzp->tbp)
1403                         break;
1404
1405                 for (i = 0; i < tzp->num_tbps; i++) {
1406                         if (tzp->tbp[i].cdev == cdev) {
1407                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1408                                 tzp->tbp[i].cdev = NULL;
1409                         }
1410                 }
1411         }
1412
1413         mutex_unlock(&thermal_list_lock);
1414
1415         cancel_delayed_work_sync(&tz->poll_queue);
1416
1417         thermal_set_governor(tz, NULL);
1418
1419         thermal_remove_hwmon_sysfs(tz);
1420         ida_simple_remove(&thermal_tz_ida, tz->id);
1421         ida_destroy(&tz->ida);
1422         mutex_destroy(&tz->lock);
1423         device_unregister(&tz->device);
1424 }
1425 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1426
1427 /**
1428  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1429  * @name: thermal zone name to fetch the temperature
1430  *
1431  * When only one zone is found with the passed name, returns a reference to it.
1432  *
1433  * Return: On success returns a reference to an unique thermal zone with
1434  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1435  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1436  */
1437 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1438 {
1439         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1440         unsigned int found = 0;
1441
1442         if (!name)
1443                 goto exit;
1444
1445         mutex_lock(&thermal_list_lock);
1446         list_for_each_entry(pos, &thermal_tz_list, node)
1447                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1448                         found++;
1449                         ref = pos;
1450                 }
1451         mutex_unlock(&thermal_list_lock);
1452
1453         /* nothing has been found, thus an error code for it */
1454         if (found == 0)
1455                 ref = ERR_PTR(-ENODEV);
1456         else if (found > 1)
1457         /* Success only when an unique zone is found */
1458                 ref = ERR_PTR(-EEXIST);
1459
1460 exit:
1461         return ref;
1462 }
1463 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1464
1465 static int thermal_pm_notify(struct notifier_block *nb,
1466                              unsigned long mode, void *_unused)
1467 {
1468         struct thermal_zone_device *tz;
1469         enum thermal_device_mode tz_mode;
1470
1471         switch (mode) {
1472         case PM_HIBERNATION_PREPARE:
1473         case PM_RESTORE_PREPARE:
1474         case PM_SUSPEND_PREPARE:
1475                 atomic_set(&in_suspend, 1);
1476                 break;
1477         case PM_POST_HIBERNATION:
1478         case PM_POST_RESTORE:
1479         case PM_POST_SUSPEND:
1480                 atomic_set(&in_suspend, 0);
1481                 list_for_each_entry(tz, &thermal_tz_list, node) {
1482                         tz_mode = THERMAL_DEVICE_ENABLED;
1483                         if (tz->ops->get_mode)
1484                                 tz->ops->get_mode(tz, &tz_mode);
1485
1486                         if (tz_mode == THERMAL_DEVICE_DISABLED)
1487                                 continue;
1488
1489                         thermal_zone_device_init(tz);
1490                         thermal_zone_device_update(tz,
1491                                                    THERMAL_EVENT_UNSPECIFIED);
1492                 }
1493                 break;
1494         default:
1495                 break;
1496         }
1497         return 0;
1498 }
1499
1500 static struct notifier_block thermal_pm_nb = {
1501         .notifier_call = thermal_pm_notify,
1502 };
1503
1504 static int __init thermal_init(void)
1505 {
1506         int result;
1507
1508         mutex_init(&poweroff_lock);
1509         result = thermal_register_governors();
1510         if (result)
1511                 goto error;
1512
1513         result = class_register(&thermal_class);
1514         if (result)
1515                 goto unregister_governors;
1516
1517         result = of_parse_thermal_zones();
1518         if (result)
1519                 goto unregister_class;
1520
1521         result = register_pm_notifier(&thermal_pm_nb);
1522         if (result)
1523                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1524                         result);
1525
1526         return 0;
1527
1528 unregister_class:
1529         class_unregister(&thermal_class);
1530 unregister_governors:
1531         thermal_unregister_governors();
1532 error:
1533         ida_destroy(&thermal_tz_ida);
1534         ida_destroy(&thermal_cdev_ida);
1535         mutex_destroy(&thermal_list_lock);
1536         mutex_destroy(&thermal_governor_lock);
1537         mutex_destroy(&poweroff_lock);
1538         return result;
1539 }
1540 core_initcall(thermal_init);