drivers/thermal/thermal_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/export.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <linux/suspend.h>
  23
  24 #define CREATE_TRACE_POINTS
  25 #include <trace/events/thermal.h>
  26
  27 #include "thermal_core.h"
  28 #include "thermal_hwmon.h"
  29
  30 static DEFINE_IDA(thermal_tz_ida);
  31 static DEFINE_IDA(thermal_cdev_ida);
  32
  33 static LIST_HEAD(thermal_tz_list);
  34 static LIST_HEAD(thermal_cdev_list);
  35 static LIST_HEAD(thermal_governor_list);
  36
  37 static DEFINE_MUTEX(thermal_list_lock);
  38 static DEFINE_MUTEX(thermal_governor_lock);
  39 static DEFINE_MUTEX(poweroff_lock);
  40
  41 static atomic_t in_suspend;
  42 static bool power_off_triggered;
  43
  44 static struct thermal_governor *def_governor;
  45
  46 /*
  47  * Governor section: set of functions to handle thermal governors
  48  *
  49  * Functions to help in the life cycle of thermal governors within
  50  * the thermal core and by the thermal governor code.
  51  */
  52
  53 static struct thermal_governor *__find_governor(const char *name)
  54 {
  55         struct thermal_governor *pos;
  56
  57         if (!name || !name[0])
  58                 return def_governor;
  59
  60         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  61                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  62                         return pos;
  63
  64         return NULL;
  65 }
  66
  67 /**
  68  * bind_previous_governor() - bind the previous governor of the thermal zone
  69  * @tz:         a valid pointer to a struct thermal_zone_device
  70  * @failed_gov_name:    the name of the governor that failed to register
  71  *
  72  * Register the previous governor of the thermal zone after a new
  73  * governor has failed to be bound.
  74  */
  75 static void bind_previous_governor(struct thermal_zone_device *tz,
  76                                    const char *failed_gov_name)
  77 {
  78         if (tz->governor && tz->governor->bind_to_tz) {
  79                 if (tz->governor->bind_to_tz(tz)) {
  80                         dev_err(&tz->device,
  81                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  82                                 failed_gov_name, tz->governor->name, tz->type);
  83                         tz->governor = NULL;
  84                 }
  85         }
  86 }
  87
  88 /**
  89  * thermal_set_governor() - Switch to another governor
  90  * @tz:         a valid pointer to a struct thermal_zone_device
  91  * @new_gov:    pointer to the new governor
  92  *
  93  * Change the governor of thermal zone @tz.
  94  *
  95  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  96  */
  97 static int thermal_set_governor(struct thermal_zone_device *tz,
  98                                 struct thermal_governor *new_gov)
  99 {
 100         int ret = 0;
 101
 102         if (tz->governor && tz->governor->unbind_from_tz)
 103                 tz->governor->unbind_from_tz(tz);
 104
 105         if (new_gov && new_gov->bind_to_tz) {
 106                 ret = new_gov->bind_to_tz(tz);
 107                 if (ret) {
 108                         bind_previous_governor(tz, new_gov->name);
 109
 110                         return ret;
 111                 }
 112         }
 113
 114         tz->governor = new_gov;
 115
 116         return ret;
 117 }
 118
 119 int thermal_register_governor(struct thermal_governor *governor)
 120 {
 121         int err;
 122         const char *name;
 123         struct thermal_zone_device *pos;
 124
 125         if (!governor)
 126                 return -EINVAL;
 127
 128         mutex_lock(&thermal_governor_lock);
 129
 130         err = -EBUSY;
 131         if (!__find_governor(governor->name)) {
 132                 bool match_default;
 133
 134                 err = 0;
 135                 list_add(&governor->governor_list, &thermal_governor_list);
 136                 match_default = !strncmp(governor->name,
 137                                          DEFAULT_THERMAL_GOVERNOR,
 138                                          THERMAL_NAME_LENGTH);
 139
 140                 if (!def_governor && match_default)
 141                         def_governor = governor;
 142         }
 143
 144         mutex_lock(&thermal_list_lock);
 145
 146         list_for_each_entry(pos, &thermal_tz_list, node) {
 147                 /*
 148                  * only thermal zones with specified tz->tzp->governor_name
 149                  * may run with tz->govenor unset
 150                  */
 151                 if (pos->governor)
 152                         continue;
 153
 154                 name = pos->tzp->governor_name;
 155
 156                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 157                         int ret;
 158
 159                         ret = thermal_set_governor(pos, governor);
 160                         if (ret)
 161                                 dev_err(&pos->device,
 162                                         "Failed to set governor %s for thermal zone %s: %d\n",
 163                                         governor->name, pos->type, ret);
 164                 }
 165         }
 166
 167         mutex_unlock(&thermal_list_lock);
 168         mutex_unlock(&thermal_governor_lock);
 169
 170         return err;
 171 }
 172
 173 void thermal_unregister_governor(struct thermal_governor *governor)
 174 {
 175         struct thermal_zone_device *pos;
 176
 177         if (!governor)
 178                 return;
 179
 180         mutex_lock(&thermal_governor_lock);
 181
 182         if (!__find_governor(governor->name))
 183                 goto exit;
 184
 185         mutex_lock(&thermal_list_lock);
 186
 187         list_for_each_entry(pos, &thermal_tz_list, node) {
 188                 if (!strncasecmp(pos->governor->name, governor->name,
 189                                  THERMAL_NAME_LENGTH))
 190                         thermal_set_governor(pos, NULL);
 191         }
 192
 193         mutex_unlock(&thermal_list_lock);
 194         list_del(&governor->governor_list);
 195 exit:
 196         mutex_unlock(&thermal_governor_lock);
 197 }
 198
 199 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 200                                    char *policy)
 201 {
 202         struct thermal_governor *gov;
 203         int ret = -EINVAL;
 204
 205         mutex_lock(&thermal_governor_lock);
 206         mutex_lock(&tz->lock);
 207
 208         gov = __find_governor(strim(policy));
 209         if (!gov)
 210                 goto exit;
 211
 212         ret = thermal_set_governor(tz, gov);
 213
 214 exit:
 215         mutex_unlock(&tz->lock);
 216         mutex_unlock(&thermal_governor_lock);
 217
 218         thermal_notify_tz_gov_change(tz->id, policy);
 219
 220         return ret;
 221 }
 222
 223 int thermal_build_list_of_policies(char *buf)
 224 {
 225         struct thermal_governor *pos;
 226         ssize_t count = 0;
 227         ssize_t size = PAGE_SIZE;
 228
 229         mutex_lock(&thermal_governor_lock);
 230
 231         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 232                 size = PAGE_SIZE - count;
 233                 count += scnprintf(buf + count, size, "%s ", pos->name);
 234         }
 235         count += scnprintf(buf + count, size, "\n");
 236
 237         mutex_unlock(&thermal_governor_lock);
 238
 239         return count;
 240 }
 241
 242 static void __init thermal_unregister_governors(void)
 243 {
 244         struct thermal_governor **governor;
 245
 246         for_each_governor_table(governor)
 247                 thermal_unregister_governor(*governor);
 248 }
 249
 250 static int __init thermal_register_governors(void)
 251 {
 252         int ret = 0;
 253         struct thermal_governor **governor;
 254
 255         for_each_governor_table(governor) {
 256                 ret = thermal_register_governor(*governor);
 257                 if (ret) {
 258                         pr_err("Failed to register governor: '%s'",
 259                                (*governor)->name);
 260                         break;
 261                 }
 262
 263                 pr_info("Registered thermal governor '%s'",
 264                         (*governor)->name);
 265         }
 266
 267         if (ret) {
 268                 struct thermal_governor **gov;
 269
 270                 for_each_governor_table(gov) {
 271                         if (gov == governor)
 272                                 break;
 273                         thermal_unregister_governor(*gov);
 274                 }
 275         }
 276
 277         return ret;
 278 }
 279
 280 /*
 281  * Zone update section: main control loop applied to each zone while monitoring
 282  *
 283  * in polling mode. The monitoring is done using a workqueue.
 284  * Same update may be done on a zone by calling thermal_zone_device_update().
 285  *
 286  * An update means:
 287  * - Non-critical trips will invoke the governor responsible for that zone;
 288  * - Hot trips will produce a notification to userspace;
 289  * - Critical trip point will cause a system shutdown.
 290  */
 291 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 292                                             unsigned long delay)
 293 {
 294         if (delay)
 295                 mod_delayed_work(system_freezable_power_efficient_wq,
 296                                  &tz->poll_queue, delay);
 297         else
 298                 cancel_delayed_work(&tz->poll_queue);
 299 }
 300
 301 static inline bool should_stop_polling(struct thermal_zone_device *tz)
 302 {
 303         return !thermal_zone_device_is_enabled(tz);
 304 }
 305
 306 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 307 {
 308         bool stop;
 309
 310         stop = should_stop_polling(tz);
 311
 312         mutex_lock(&tz->lock);
 313
 314         if (!stop && tz->passive)
 315                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 316         else if (!stop && tz->polling_delay)
 317                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 318         else
 319                 thermal_zone_device_set_polling(tz, 0);
 320
 321         mutex_unlock(&tz->lock);
 322 }
 323
 324 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 325 {
 326         tz->governor ? tz->governor->throttle(tz, trip) :
 327                        def_governor->throttle(tz, trip);
 328 }
 329
 330 /**
 331  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 332  * @work: work_struct associated with the emergency poweroff function
 333  *
 334  * This function is called in very critical situations to force
 335  * a kernel poweroff after a configurable timeout value.
 336  */
 337 static void thermal_emergency_poweroff_func(struct work_struct *work)
 338 {
 339         /*
 340          * We have reached here after the emergency thermal shutdown
 341          * Waiting period has expired. This means orderly_poweroff has
 342          * not been able to shut off the system for some reason.
 343          * Try to shut down the system immediately using kernel_power_off
 344          * if populated
 345          */
 346         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 347         kernel_power_off();
 348
 349         /*
 350          * Worst of the worst case trigger emergency restart
 351          */
 352         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 353         emergency_restart();
 354 }
 355
 356 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 357                             thermal_emergency_poweroff_func);
 358
 359 /**
 360  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 361  *
 362  * This may be called from any critical situation to trigger a system shutdown
 363  * after a known period of time. By default this is not scheduled.
 364  */
 365 static void thermal_emergency_poweroff(void)
 366 {
 367         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 368         /*
 369          * poweroff_delay_ms must be a carefully profiled positive value.
 370          * Its a must for thermal_emergency_poweroff_work to be scheduled
 371          */
 372         if (poweroff_delay_ms <= 0)
 373                 return;
 374         schedule_delayed_work(&thermal_emergency_poweroff_work,
 375                               msecs_to_jiffies(poweroff_delay_ms));
 376 }
 377
 378 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 379 {
 380         dev_emerg(&tz->device, "%s: critical temperature reached, "
 381                   "shutting down\n", tz->type);
 382
 383         mutex_lock(&poweroff_lock);
 384         if (!power_off_triggered) {
 385                 /*
 386                  * Queue a backup emergency shutdown in the event of
 387                  * orderly_poweroff failure
 388                  */
 389                 thermal_emergency_poweroff();
 390                 orderly_poweroff(true);
 391                 power_off_triggered = true;
 392         }
 393         mutex_unlock(&poweroff_lock);
 394 }
 395 EXPORT_SYMBOL(thermal_zone_device_critical);
 396
 397 static void handle_critical_trips(struct thermal_zone_device *tz,
 398                                   int trip, enum thermal_trip_type trip_type)
 399 {
 400         int trip_temp;
 401
 402         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 403
 404         /* If we have not crossed the trip_temp, we do not care. */
 405         if (trip_temp <= 0 || tz->temperature < trip_temp)
 406                 return;
 407
 408         trace_thermal_zone_trip(tz, trip, trip_type);
 409
 410         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
 411                 tz->ops->hot(tz);
 412         else if (trip_type == THERMAL_TRIP_CRITICAL)
 413                 tz->ops->critical(tz);
 414 }
 415
 416 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 417 {
 418         enum thermal_trip_type type;
 419         int trip_temp, hyst = 0;
 420
 421         /* Ignore disabled trip points */
 422         if (test_bit(trip, &tz->trips_disabled))
 423                 return;
 424
 425         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 426         tz->ops->get_trip_type(tz, trip, &type);
 427         if (tz->ops->get_trip_hyst)
 428                 tz->ops->get_trip_hyst(tz, trip, &hyst);
 429
 430         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 431                 if (tz->last_temperature < trip_temp &&
 432                     tz->temperature >= trip_temp)
 433                         thermal_notify_tz_trip_up(tz->id, trip);
 434                 if (tz->last_temperature >= trip_temp &&
 435                     tz->temperature < (trip_temp - hyst))
 436                         thermal_notify_tz_trip_down(tz->id, trip);
 437         }
 438
 439         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 440                 handle_critical_trips(tz, trip, type);
 441         else
 442                 handle_non_critical_trips(tz, trip);
 443         /*
 444          * Alright, we handled this trip successfully.
 445          * So, start monitoring again.
 446          */
 447         monitor_thermal_zone(tz);
 448 }
 449
 450 static void update_temperature(struct thermal_zone_device *tz)
 451 {
 452         int temp, ret;
 453
 454         ret = thermal_zone_get_temp(tz, &temp);
 455         if (ret) {
 456                 if (ret != -EAGAIN)
 457                         dev_warn(&tz->device,
 458                                  "failed to read out thermal zone (%d)\n",
 459                                  ret);
 460                 return;
 461         }
 462
 463         mutex_lock(&tz->lock);
 464         tz->last_temperature = tz->temperature;
 465         tz->temperature = temp;
 466         mutex_unlock(&tz->lock);
 467
 468         trace_thermal_temperature(tz);
 469
 470         thermal_genl_sampling_temp(tz->id, temp);
 471 }
 472
 473 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 474 {
 475         struct thermal_instance *pos;
 476         tz->temperature = THERMAL_TEMP_INVALID;
 477         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 478                 pos->initialized = false;
 479 }
 480
 481 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 482 {
 483         tz->passive = 0;
 484         thermal_zone_device_init(tz);
 485 }
 486
 487 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 488                                         enum thermal_device_mode mode)
 489 {
 490         int ret = 0;
 491
 492         mutex_lock(&tz->lock);
 493
 494         /* do nothing if mode isn't changing */
 495         if (mode == tz->mode) {
 496                 mutex_unlock(&tz->lock);
 497
 498                 return ret;
 499         }
 500
 501         if (tz->ops->change_mode)
 502                 ret = tz->ops->change_mode(tz, mode);
 503
 504         if (!ret)
 505                 tz->mode = mode;
 506
 507         mutex_unlock(&tz->lock);
 508
 509         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 510
 511         if (mode == THERMAL_DEVICE_ENABLED)
 512                 thermal_notify_tz_enable(tz->id);
 513         else
 514                 thermal_notify_tz_disable(tz->id);
 515
 516         return ret;
 517 }
 518
 519 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 520 {
 521         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 522 }
 523 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 524
 525 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 526 {
 527         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 528 }
 529 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 530
 531 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 532 {
 533         enum thermal_device_mode mode;
 534
 535         mutex_lock(&tz->lock);
 536
 537         mode = tz->mode;
 538
 539         mutex_unlock(&tz->lock);
 540
 541         return mode == THERMAL_DEVICE_ENABLED;
 542 }
 543
 544 void thermal_zone_device_update(struct thermal_zone_device *tz,
 545                                 enum thermal_notify_event event)
 546 {
 547         int count;
 548
 549         if (should_stop_polling(tz))
 550                 return;
 551
 552         if (atomic_read(&in_suspend))
 553                 return;
 554
 555         if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
 556                       "'get_temp' ops set\n", __func__))
 557                 return;
 558
 559         update_temperature(tz);
 560
 561         thermal_zone_set_trips(tz);
 562
 563         tz->notify_event = event;
 564
 565         for (count = 0; count < tz->trips; count++)
 566                 handle_thermal_trip(tz, count);
 567 }
 568 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 569
 570 /**
 571  * thermal_notify_framework - Sensor drivers use this API to notify framework
 572  * @tz:         thermal zone device
 573  * @trip:       indicates which trip point has been crossed
 574  *
 575  * This function handles the trip events from sensor drivers. It starts
 576  * throttling the cooling devices according to the policy configured.
 577  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 578  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 579  * The throttling policy is based on the configured platform data; if no
 580  * platform data is provided, this uses the step_wise throttling policy.
 581  */
 582 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 583 {
 584         handle_thermal_trip(tz, trip);
 585 }
 586 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 587
 588 static void thermal_zone_device_check(struct work_struct *work)
 589 {
 590         struct thermal_zone_device *tz = container_of(work, struct
 591                                                       thermal_zone_device,
 592                                                       poll_queue.work);
 593         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 594 }
 595
 596 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 597                               void *data)
 598 {
 599         struct thermal_governor *gov;
 600         int ret = 0;
 601
 602         mutex_lock(&thermal_governor_lock);
 603         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 604                 ret = cb(gov, data);
 605                 if (ret)
 606                         break;
 607         }
 608         mutex_unlock(&thermal_governor_lock);
 609
 610         return ret;
 611 }
 612
 613 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 614                                               void *), void *data)
 615 {
 616         struct thermal_cooling_device *cdev;
 617         int ret = 0;
 618
 619         mutex_lock(&thermal_list_lock);
 620         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 621                 ret = cb(cdev, data);
 622                 if (ret)
 623                         break;
 624         }
 625         mutex_unlock(&thermal_list_lock);
 626
 627         return ret;
 628 }
 629
 630 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 631                           void *data)
 632 {
 633         struct thermal_zone_device *tz;
 634         int ret = 0;
 635
 636         mutex_lock(&thermal_list_lock);
 637         list_for_each_entry(tz, &thermal_tz_list, node) {
 638                 ret = cb(tz, data);
 639                 if (ret)
 640                         break;
 641         }
 642         mutex_unlock(&thermal_list_lock);
 643
 644         return ret;
 645 }
 646
 647 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 648 {
 649         struct thermal_zone_device *tz, *match = NULL;
 650
 651         mutex_lock(&thermal_list_lock);
 652         list_for_each_entry(tz, &thermal_tz_list, node) {
 653                 if (tz->id == id) {
 654                         match = tz;
 655                         break;
 656                 }
 657         }
 658         mutex_unlock(&thermal_list_lock);
 659
 660         return match;
 661 }
 662
 663 /*
 664  * Device management section: cooling devices, zones devices, and binding
 665  *
 666  * Set of functions provided by the thermal core for:
 667  * - cooling devices lifecycle: registration, unregistration,
 668  *                              binding, and unbinding.
 669  * - thermal zone devices lifecycle: registration, unregistration,
 670  *                                   binding, and unbinding.
 671  */
 672
 673 /**
 674  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 675  * @tz:         pointer to struct thermal_zone_device
 676  * @trip:       indicates which trip point the cooling devices is
 677  *              associated with in this thermal zone.
 678  * @cdev:       pointer to struct thermal_cooling_device
 679  * @upper:      the Maximum cooling state for this trip point.
 680  *              THERMAL_NO_LIMIT means no upper limit,
 681  *              and the cooling device can be in max_state.
 682  * @lower:      the Minimum cooling state can be used for this trip point.
 683  *              THERMAL_NO_LIMIT means no lower limit,
 684  *              and the cooling device can be in cooling state 0.
 685  * @weight:     The weight of the cooling device to be bound to the
 686  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 687  *              default value
 688  *
 689  * This interface function bind a thermal cooling device to the certain trip
 690  * point of a thermal zone device.
 691  * This function is usually called in the thermal zone device .bind callback.
 692  *
 693  * Return: 0 on success, the proper error value otherwise.
 694  */
 695 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 696                                      int trip,
 697                                      struct thermal_cooling_device *cdev,
 698                                      unsigned long upper, unsigned long lower,
 699                                      unsigned int weight)
 700 {
 701         struct thermal_instance *dev;
 702         struct thermal_instance *pos;
 703         struct thermal_zone_device *pos1;
 704         struct thermal_cooling_device *pos2;
 705         unsigned long max_state;
 706         int result, ret;
 707
 708         if (trip >= tz->trips || trip < 0)
 709                 return -EINVAL;
 710
 711         list_for_each_entry(pos1, &thermal_tz_list, node) {
 712                 if (pos1 == tz)
 713                         break;
 714         }
 715         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 716                 if (pos2 == cdev)
 717                         break;
 718         }
 719
 720         if (tz != pos1 || cdev != pos2)
 721                 return -EINVAL;
 722
 723         ret = cdev->ops->get_max_state(cdev, &max_state);
 724         if (ret)
 725                 return ret;
 726
 727         /* lower default 0, upper default max_state */
 728         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 729         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 730
 731         if (lower > upper || upper > max_state)
 732                 return -EINVAL;
 733
 734         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 735         if (!dev)
 736                 return -ENOMEM;
 737         dev->tz = tz;
 738         dev->cdev = cdev;
 739         dev->trip = trip;
 740         dev->upper = upper;
 741         dev->lower = lower;
 742         dev->target = THERMAL_NO_TARGET;
 743         dev->weight = weight;
 744
 745         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 746         if (result < 0)
 747                 goto free_mem;
 748
 749         dev->id = result;
 750         sprintf(dev->name, "cdev%d", dev->id);
 751         result =
 752             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 753         if (result)
 754                 goto release_ida;
 755
 756         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 757         sysfs_attr_init(&dev->attr.attr);
 758         dev->attr.attr.name = dev->attr_name;
 759         dev->attr.attr.mode = 0444;
 760         dev->attr.show = trip_point_show;
 761         result = device_create_file(&tz->device, &dev->attr);
 762         if (result)
 763                 goto remove_symbol_link;
 764
 765         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 766         sysfs_attr_init(&dev->weight_attr.attr);
 767         dev->weight_attr.attr.name = dev->weight_attr_name;
 768         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 769         dev->weight_attr.show = weight_show;
 770         dev->weight_attr.store = weight_store;
 771         result = device_create_file(&tz->device, &dev->weight_attr);
 772         if (result)
 773                 goto remove_trip_file;
 774
 775         mutex_lock(&tz->lock);
 776         mutex_lock(&cdev->lock);
 777         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 778                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 779                         result = -EEXIST;
 780                         break;
 781                 }
 782         if (!result) {
 783                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 784                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 785                 atomic_set(&tz->need_update, 1);
 786         }
 787         mutex_unlock(&cdev->lock);
 788         mutex_unlock(&tz->lock);
 789
 790         if (!result)
 791                 return 0;
 792
 793         device_remove_file(&tz->device, &dev->weight_attr);
 794 remove_trip_file:
 795         device_remove_file(&tz->device, &dev->attr);
 796 remove_symbol_link:
 797         sysfs_remove_link(&tz->device.kobj, dev->name);
 798 release_ida:
 799         ida_simple_remove(&tz->ida, dev->id);
 800 free_mem:
 801         kfree(dev);
 802         return result;
 803 }
 804 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 805
 806 /**
 807  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 808  *                                        thermal zone.
 809  * @tz:         pointer to a struct thermal_zone_device.
 810  * @trip:       indicates which trip point the cooling devices is
 811  *              associated with in this thermal zone.
 812  * @cdev:       pointer to a struct thermal_cooling_device.
 813  *
 814  * This interface function unbind a thermal cooling device from the certain
 815  * trip point of a thermal zone device.
 816  * This function is usually called in the thermal zone device .unbind callback.
 817  *
 818  * Return: 0 on success, the proper error value otherwise.
 819  */
 820 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 821                                        int trip,
 822                                        struct thermal_cooling_device *cdev)
 823 {
 824         struct thermal_instance *pos, *next;
 825
 826         mutex_lock(&tz->lock);
 827         mutex_lock(&cdev->lock);
 828         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 829                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 830                         list_del(&pos->tz_node);
 831                         list_del(&pos->cdev_node);
 832                         mutex_unlock(&cdev->lock);
 833                         mutex_unlock(&tz->lock);
 834                         goto unbind;
 835                 }
 836         }
 837         mutex_unlock(&cdev->lock);
 838         mutex_unlock(&tz->lock);
 839
 840         return -ENODEV;
 841
 842 unbind:
 843         device_remove_file(&tz->device, &pos->weight_attr);
 844         device_remove_file(&tz->device, &pos->attr);
 845         sysfs_remove_link(&tz->device.kobj, pos->name);
 846         ida_simple_remove(&tz->ida, pos->id);
 847         kfree(pos);
 848         return 0;
 849 }
 850 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 851
 852 static void thermal_release(struct device *dev)
 853 {
 854         struct thermal_zone_device *tz;
 855         struct thermal_cooling_device *cdev;
 856
 857         if (!strncmp(dev_name(dev), "thermal_zone",
 858                      sizeof("thermal_zone") - 1)) {
 859                 tz = to_thermal_zone(dev);
 860                 thermal_zone_destroy_device_groups(tz);
 861                 kfree(tz);
 862         } else if (!strncmp(dev_name(dev), "cooling_device",
 863                             sizeof("cooling_device") - 1)) {
 864                 cdev = to_cooling_device(dev);
 865                 kfree(cdev);
 866         }
 867 }
 868
 869 static struct class thermal_class = {
 870         .name = "thermal",
 871         .dev_release = thermal_release,
 872 };
 873
 874 static inline
 875 void print_bind_err_msg(struct thermal_zone_device *tz,
 876                         struct thermal_cooling_device *cdev, int ret)
 877 {
 878         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 879                 tz->type, cdev->type, ret);
 880 }
 881
 882 static void __bind(struct thermal_zone_device *tz, int mask,
 883                    struct thermal_cooling_device *cdev,
 884                    unsigned long *limits,
 885                    unsigned int weight)
 886 {
 887         int i, ret;
 888
 889         for (i = 0; i < tz->trips; i++) {
 890                 if (mask & (1 << i)) {
 891                         unsigned long upper, lower;
 892
 893                         upper = THERMAL_NO_LIMIT;
 894                         lower = THERMAL_NO_LIMIT;
 895                         if (limits) {
 896                                 lower = limits[i * 2];
 897                                 upper = limits[i * 2 + 1];
 898                         }
 899                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 900                                                                upper, lower,
 901                                                                weight);
 902                         if (ret)
 903                                 print_bind_err_msg(tz, cdev, ret);
 904                 }
 905         }
 906 }
 907
 908 static void bind_cdev(struct thermal_cooling_device *cdev)
 909 {
 910         int i, ret;
 911         const struct thermal_zone_params *tzp;
 912         struct thermal_zone_device *pos = NULL;
 913
 914         mutex_lock(&thermal_list_lock);
 915
 916         list_for_each_entry(pos, &thermal_tz_list, node) {
 917                 if (!pos->tzp && !pos->ops->bind)
 918                         continue;
 919
 920                 if (pos->ops->bind) {
 921                         ret = pos->ops->bind(pos, cdev);
 922                         if (ret)
 923                                 print_bind_err_msg(pos, cdev, ret);
 924                         continue;
 925                 }
 926
 927                 tzp = pos->tzp;
 928                 if (!tzp || !tzp->tbp)
 929                         continue;
 930
 931                 for (i = 0; i < tzp->num_tbps; i++) {
 932                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 933                                 continue;
 934                         if (tzp->tbp[i].match(pos, cdev))
 935                                 continue;
 936                         tzp->tbp[i].cdev = cdev;
 937                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 938                                tzp->tbp[i].binding_limits,
 939                                tzp->tbp[i].weight);
 940                 }
 941         }
 942
 943         mutex_unlock(&thermal_list_lock);
 944 }
 945
 946 /**
 947  * __thermal_cooling_device_register() - register a new thermal cooling device
 948  * @np:         a pointer to a device tree node.
 949  * @type:       the thermal cooling device type.
 950  * @devdata:    device private data.
 951  * @ops:                standard thermal cooling devices callbacks.
 952  *
 953  * This interface function adds a new thermal cooling device (fan/processor/...)
 954  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 955  * to all the thermal zone devices registered at the same time.
 956  * It also gives the opportunity to link the cooling device to a device tree
 957  * node, so that it can be bound to a thermal zone created out of device tree.
 958  *
 959  * Return: a pointer to the created struct thermal_cooling_device or an
 960  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 961  */
 962 static struct thermal_cooling_device *
 963 __thermal_cooling_device_register(struct device_node *np,
 964                                   const char *type, void *devdata,
 965                                   const struct thermal_cooling_device_ops *ops)
 966 {
 967         struct thermal_cooling_device *cdev;
 968         struct thermal_zone_device *pos = NULL;
 969         int result;
 970
 971         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 972                 return ERR_PTR(-EINVAL);
 973
 974         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 975             !ops->set_cur_state)
 976                 return ERR_PTR(-EINVAL);
 977
 978         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 979         if (!cdev)
 980                 return ERR_PTR(-ENOMEM);
 981
 982         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 983         if (result < 0) {
 984                 kfree(cdev);
 985                 return ERR_PTR(result);
 986         }
 987
 988         cdev->id = result;
 989         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 990         mutex_init(&cdev->lock);
 991         INIT_LIST_HEAD(&cdev->thermal_instances);
 992         cdev->np = np;
 993         cdev->ops = ops;
 994         cdev->updated = false;
 995         cdev->device.class = &thermal_class;
 996         cdev->devdata = devdata;
 997         thermal_cooling_device_setup_sysfs(cdev);
 998         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 999         result = device_register(&cdev->device);
1000         if (result) {
1001                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1002                 put_device(&cdev->device);
1003                 return ERR_PTR(result);
1004         }
1005
1006         /* Add 'this' new cdev to the global cdev list */
1007         mutex_lock(&thermal_list_lock);
1008         list_add(&cdev->node, &thermal_cdev_list);
1009         mutex_unlock(&thermal_list_lock);
1010
1011         /* Update binding information for 'this' new cdev */
1012         bind_cdev(cdev);
1013
1014         mutex_lock(&thermal_list_lock);
1015         list_for_each_entry(pos, &thermal_tz_list, node)
1016                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1017                         thermal_zone_device_update(pos,
1018                                                    THERMAL_EVENT_UNSPECIFIED);
1019         mutex_unlock(&thermal_list_lock);
1020
1021         return cdev;
1022 }
1023
1024 /**
1025  * thermal_cooling_device_register() - register a new thermal cooling device
1026  * @type:       the thermal cooling device type.
1027  * @devdata:    device private data.
1028  * @ops:                standard thermal cooling devices callbacks.
1029  *
1030  * This interface function adds a new thermal cooling device (fan/processor/...)
1031  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1032  * to all the thermal zone devices registered at the same time.
1033  *
1034  * Return: a pointer to the created struct thermal_cooling_device or an
1035  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1036  */
1037 struct thermal_cooling_device *
1038 thermal_cooling_device_register(const char *type, void *devdata,
1039                                 const struct thermal_cooling_device_ops *ops)
1040 {
1041         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1042 }
1043 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1044
1045 /**
1046  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1047  * @np:         a pointer to a device tree node.
1048  * @type:       the thermal cooling device type.
1049  * @devdata:    device private data.
1050  * @ops:                standard thermal cooling devices callbacks.
1051  *
1052  * This function will register a cooling device with device tree node reference.
1053  * This interface function adds a new thermal cooling device (fan/processor/...)
1054  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1055  * to all the thermal zone devices registered at the same time.
1056  *
1057  * Return: a pointer to the created struct thermal_cooling_device or an
1058  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1059  */
1060 struct thermal_cooling_device *
1061 thermal_of_cooling_device_register(struct device_node *np,
1062                                    const char *type, void *devdata,
1063                                    const struct thermal_cooling_device_ops *ops)
1064 {
1065         return __thermal_cooling_device_register(np, type, devdata, ops);
1066 }
1067 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1068
1069 static void thermal_cooling_device_release(struct device *dev, void *res)
1070 {
1071         thermal_cooling_device_unregister(
1072                                 *(struct thermal_cooling_device **)res);
1073 }
1074
1075 /**
1076  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1077  *                                             device
1078  * @dev:        a valid struct device pointer of a sensor device.
1079  * @np:         a pointer to a device tree node.
1080  * @type:       the thermal cooling device type.
1081  * @devdata:    device private data.
1082  * @ops:        standard thermal cooling devices callbacks.
1083  *
1084  * This function will register a cooling device with device tree node reference.
1085  * This interface function adds a new thermal cooling device (fan/processor/...)
1086  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1087  * to all the thermal zone devices registered at the same time.
1088  *
1089  * Return: a pointer to the created struct thermal_cooling_device or an
1090  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1091  */
1092 struct thermal_cooling_device *
1093 devm_thermal_of_cooling_device_register(struct device *dev,
1094                                 struct device_node *np,
1095                                 char *type, void *devdata,
1096                                 const struct thermal_cooling_device_ops *ops)
1097 {
1098         struct thermal_cooling_device **ptr, *tcd;
1099
1100         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1101                            GFP_KERNEL);
1102         if (!ptr)
1103                 return ERR_PTR(-ENOMEM);
1104
1105         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1106         if (IS_ERR(tcd)) {
1107                 devres_free(ptr);
1108                 return tcd;
1109         }
1110
1111         *ptr = tcd;
1112         devres_add(dev, ptr);
1113
1114         return tcd;
1115 }
1116 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1117
1118 static void __unbind(struct thermal_zone_device *tz, int mask,
1119                      struct thermal_cooling_device *cdev)
1120 {
1121         int i;
1122
1123         for (i = 0; i < tz->trips; i++)
1124                 if (mask & (1 << i))
1125                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1126 }
1127
1128 /**
1129  * thermal_cooling_device_unregister - removes a thermal cooling device
1130  * @cdev:       the thermal cooling device to remove.
1131  *
1132  * thermal_cooling_device_unregister() must be called when a registered
1133  * thermal cooling device is no longer needed.
1134  */
1135 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1136 {
1137         int i;
1138         const struct thermal_zone_params *tzp;
1139         struct thermal_zone_device *tz;
1140         struct thermal_cooling_device *pos = NULL;
1141
1142         if (!cdev)
1143                 return;
1144
1145         mutex_lock(&thermal_list_lock);
1146         list_for_each_entry(pos, &thermal_cdev_list, node)
1147                 if (pos == cdev)
1148                         break;
1149         if (pos != cdev) {
1150                 /* thermal cooling device not found */
1151                 mutex_unlock(&thermal_list_lock);
1152                 return;
1153         }
1154         list_del(&cdev->node);
1155
1156         /* Unbind all thermal zones associated with 'this' cdev */
1157         list_for_each_entry(tz, &thermal_tz_list, node) {
1158                 if (tz->ops->unbind) {
1159                         tz->ops->unbind(tz, cdev);
1160                         continue;
1161                 }
1162
1163                 if (!tz->tzp || !tz->tzp->tbp)
1164                         continue;
1165
1166                 tzp = tz->tzp;
1167                 for (i = 0; i < tzp->num_tbps; i++) {
1168                         if (tzp->tbp[i].cdev == cdev) {
1169                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1170                                 tzp->tbp[i].cdev = NULL;
1171                         }
1172                 }
1173         }
1174
1175         mutex_unlock(&thermal_list_lock);
1176
1177         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1178         device_del(&cdev->device);
1179         thermal_cooling_device_destroy_sysfs(cdev);
1180         put_device(&cdev->device);
1181 }
1182 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1183
1184 static void bind_tz(struct thermal_zone_device *tz)
1185 {
1186         int i, ret;
1187         struct thermal_cooling_device *pos = NULL;
1188         const struct thermal_zone_params *tzp = tz->tzp;
1189
1190         if (!tzp && !tz->ops->bind)
1191                 return;
1192
1193         mutex_lock(&thermal_list_lock);
1194
1195         /* If there is ops->bind, try to use ops->bind */
1196         if (tz->ops->bind) {
1197                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1198                         ret = tz->ops->bind(tz, pos);
1199                         if (ret)
1200                                 print_bind_err_msg(tz, pos, ret);
1201                 }
1202                 goto exit;
1203         }
1204
1205         if (!tzp || !tzp->tbp)
1206                 goto exit;
1207
1208         list_for_each_entry(pos, &thermal_cdev_list, node) {
1209                 for (i = 0; i < tzp->num_tbps; i++) {
1210                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1211                                 continue;
1212                         if (tzp->tbp[i].match(tz, pos))
1213                                 continue;
1214                         tzp->tbp[i].cdev = pos;
1215                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1216                                tzp->tbp[i].binding_limits,
1217                                tzp->tbp[i].weight);
1218                 }
1219         }
1220 exit:
1221         mutex_unlock(&thermal_list_lock);
1222 }
1223
1224 /**
1225  * thermal_zone_device_register() - register a new thermal zone device
1226  * @type:       the thermal zone device type
1227  * @trips:      the number of trip points the thermal zone support
1228  * @mask:       a bit string indicating the writeablility of trip points
1229  * @devdata:    private device data
1230  * @ops:        standard thermal zone device callbacks
1231  * @tzp:        thermal zone platform parameters
1232  * @passive_delay: number of milliseconds to wait between polls when
1233  *                 performing passive cooling
1234  * @polling_delay: number of milliseconds to wait between polls when checking
1235  *                 whether trip points have been crossed (0 for interrupt
1236  *                 driven systems)
1237  *
1238  * This interface function adds a new thermal zone device (sensor) to
1239  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1240  * thermal cooling devices registered at the same time.
1241  * thermal_zone_device_unregister() must be called when the device is no
1242  * longer needed. The passive cooling depends on the .get_trend() return value.
1243  *
1244  * Return: a pointer to the created struct thermal_zone_device or an
1245  * in case of error, an ERR_PTR. Caller must check return value with
1246  * IS_ERR*() helpers.
1247  */
1248 struct thermal_zone_device *
1249 thermal_zone_device_register(const char *type, int trips, int mask,
1250                              void *devdata, struct thermal_zone_device_ops *ops,
1251                              struct thermal_zone_params *tzp, int passive_delay,
1252                              int polling_delay)
1253 {
1254         struct thermal_zone_device *tz;
1255         enum thermal_trip_type trip_type;
1256         int trip_temp;
1257         int id;
1258         int result;
1259         int count;
1260         struct thermal_governor *governor;
1261
1262         if (!type || strlen(type) == 0) {
1263                 pr_err("Error: No thermal zone type defined\n");
1264                 return ERR_PTR(-EINVAL);
1265         }
1266
1267         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1268                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1269                        type, THERMAL_NAME_LENGTH);
1270                 return ERR_PTR(-EINVAL);
1271         }
1272
1273         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1274                 pr_err("Error: Incorrect number of thermal trips\n");
1275                 return ERR_PTR(-EINVAL);
1276         }
1277
1278         if (!ops) {
1279                 pr_err("Error: Thermal zone device ops not defined\n");
1280                 return ERR_PTR(-EINVAL);
1281         }
1282
1283         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1284                 return ERR_PTR(-EINVAL);
1285
1286         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1287         if (!tz)
1288                 return ERR_PTR(-ENOMEM);
1289
1290         INIT_LIST_HEAD(&tz->thermal_instances);
1291         ida_init(&tz->ida);
1292         mutex_init(&tz->lock);
1293         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1294         if (id < 0) {
1295                 result = id;
1296                 goto free_tz;
1297         }
1298
1299         tz->id = id;
1300         strlcpy(tz->type, type, sizeof(tz->type));
1301
1302         if (!ops->critical)
1303                 ops->critical = thermal_zone_device_critical;
1304
1305         tz->ops = ops;
1306         tz->tzp = tzp;
1307         tz->device.class = &thermal_class;
1308         tz->devdata = devdata;
1309         tz->trips = trips;
1310         tz->passive_delay = passive_delay;
1311         tz->polling_delay = polling_delay;
1312
1313         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1314         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1315
1316         /* sys I/F */
1317         /* Add nodes that are always present via .groups */
1318         result = thermal_zone_create_device_groups(tz, mask);
1319         if (result)
1320                 goto remove_id;
1321
1322         /* A new thermal zone needs to be updated anyway. */
1323         atomic_set(&tz->need_update, 1);
1324
1325         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1326         result = device_register(&tz->device);
1327         if (result)
1328                 goto release_device;
1329
1330         for (count = 0; count < trips; count++) {
1331                 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1332                     tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1333                     !trip_temp)
1334                         set_bit(count, &tz->trips_disabled);
1335         }
1336
1337         /* Update 'this' zone's governor information */
1338         mutex_lock(&thermal_governor_lock);
1339
1340         if (tz->tzp)
1341                 governor = __find_governor(tz->tzp->governor_name);
1342         else
1343                 governor = def_governor;
1344
1345         result = thermal_set_governor(tz, governor);
1346         if (result) {
1347                 mutex_unlock(&thermal_governor_lock);
1348                 goto unregister;
1349         }
1350
1351         mutex_unlock(&thermal_governor_lock);
1352
1353         if (!tz->tzp || !tz->tzp->no_hwmon) {
1354                 result = thermal_add_hwmon_sysfs(tz);
1355                 if (result)
1356                         goto unregister;
1357         }
1358
1359         mutex_lock(&thermal_list_lock);
1360         list_add_tail(&tz->node, &thermal_tz_list);
1361         mutex_unlock(&thermal_list_lock);
1362
1363         /* Bind cooling devices for this zone */
1364         bind_tz(tz);
1365
1366         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1367
1368         thermal_zone_device_reset(tz);
1369         /* Update the new thermal zone and mark it as already updated. */
1370         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1371                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1372
1373         thermal_notify_tz_create(tz->id, tz->type);
1374
1375         return tz;
1376
1377 unregister:
1378         device_del(&tz->device);
1379 release_device:
1380         put_device(&tz->device);
1381         tz = NULL;
1382 remove_id:
1383         ida_simple_remove(&thermal_tz_ida, id);
1384 free_tz:
1385         kfree(tz);
1386         return ERR_PTR(result);
1387 }
1388 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1389
1390 /**
1391  * thermal_device_unregister - removes the registered thermal zone device
1392  * @tz: the thermal zone device to remove
1393  */
1394 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1395 {
1396         int i, tz_id;
1397         const struct thermal_zone_params *tzp;
1398         struct thermal_cooling_device *cdev;
1399         struct thermal_zone_device *pos = NULL;
1400
1401         if (!tz)
1402                 return;
1403
1404         tzp = tz->tzp;
1405         tz_id = tz->id;
1406
1407         mutex_lock(&thermal_list_lock);
1408         list_for_each_entry(pos, &thermal_tz_list, node)
1409                 if (pos == tz)
1410                         break;
1411         if (pos != tz) {
1412                 /* thermal zone device not found */
1413                 mutex_unlock(&thermal_list_lock);
1414                 return;
1415         }
1416         list_del(&tz->node);
1417
1418         /* Unbind all cdevs associated with 'this' thermal zone */
1419         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1420                 if (tz->ops->unbind) {
1421                         tz->ops->unbind(tz, cdev);
1422                         continue;
1423                 }
1424
1425                 if (!tzp || !tzp->tbp)
1426                         break;
1427
1428                 for (i = 0; i < tzp->num_tbps; i++) {
1429                         if (tzp->tbp[i].cdev == cdev) {
1430                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1431                                 tzp->tbp[i].cdev = NULL;
1432                         }
1433                 }
1434         }
1435
1436         mutex_unlock(&thermal_list_lock);
1437
1438         cancel_delayed_work_sync(&tz->poll_queue);
1439
1440         thermal_set_governor(tz, NULL);
1441
1442         thermal_remove_hwmon_sysfs(tz);
1443         ida_simple_remove(&thermal_tz_ida, tz->id);
1444         ida_destroy(&tz->ida);
1445         mutex_destroy(&tz->lock);
1446         device_unregister(&tz->device);
1447
1448         thermal_notify_tz_delete(tz_id);
1449 }
1450 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1451
1452 /**
1453  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1454  * @name: thermal zone name to fetch the temperature
1455  *
1456  * When only one zone is found with the passed name, returns a reference to it.
1457  *
1458  * Return: On success returns a reference to an unique thermal zone with
1459  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1460  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1461  */
1462 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1463 {
1464         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1465         unsigned int found = 0;
1466
1467         if (!name)
1468                 goto exit;
1469
1470         mutex_lock(&thermal_list_lock);
1471         list_for_each_entry(pos, &thermal_tz_list, node)
1472                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1473                         found++;
1474                         ref = pos;
1475                 }
1476         mutex_unlock(&thermal_list_lock);
1477
1478         /* nothing has been found, thus an error code for it */
1479         if (found == 0)
1480                 ref = ERR_PTR(-ENODEV);
1481         else if (found > 1)
1482         /* Success only when an unique zone is found */
1483                 ref = ERR_PTR(-EEXIST);
1484
1485 exit:
1486         return ref;
1487 }
1488 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1489
1490 static int thermal_pm_notify(struct notifier_block *nb,
1491                              unsigned long mode, void *_unused)
1492 {
1493         struct thermal_zone_device *tz;
1494
1495         switch (mode) {
1496         case PM_HIBERNATION_PREPARE:
1497         case PM_RESTORE_PREPARE:
1498         case PM_SUSPEND_PREPARE:
1499                 atomic_set(&in_suspend, 1);
1500                 break;
1501         case PM_POST_HIBERNATION:
1502         case PM_POST_RESTORE:
1503         case PM_POST_SUSPEND:
1504                 atomic_set(&in_suspend, 0);
1505                 list_for_each_entry(tz, &thermal_tz_list, node) {
1506                         if (!thermal_zone_device_is_enabled(tz))
1507                                 continue;
1508
1509                         thermal_zone_device_init(tz);
1510                         thermal_zone_device_update(tz,
1511                                                    THERMAL_EVENT_UNSPECIFIED);
1512                 }
1513                 break;
1514         default:
1515                 break;
1516         }
1517         return 0;
1518 }
1519
1520 static struct notifier_block thermal_pm_nb = {
1521         .notifier_call = thermal_pm_notify,
1522 };
1523
1524 static int __init thermal_init(void)
1525 {
1526         int result;
1527
1528         result = thermal_netlink_init();
1529         if (result)
1530                 goto error;
1531
1532         result = thermal_register_governors();
1533         if (result)
1534                 goto error;
1535
1536         result = class_register(&thermal_class);
1537         if (result)
1538                 goto unregister_governors;
1539
1540         result = of_parse_thermal_zones();
1541         if (result)
1542                 goto unregister_class;
1543
1544         result = register_pm_notifier(&thermal_pm_nb);
1545         if (result)
1546                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1547                         result);
1548
1549         return 0;
1550
1551 unregister_class:
1552         class_unregister(&thermal_class);
1553 unregister_governors:
1554         thermal_unregister_governors();
1555 error:
1556         ida_destroy(&thermal_tz_ida);
1557         ida_destroy(&thermal_cdev_ida);
1558         mutex_destroy(&thermal_list_lock);
1559         mutex_destroy(&thermal_governor_lock);
1560         mutex_destroy(&poweroff_lock);
1561         return result;
1562 }
1563 postcore_initcall(thermal_init);