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                                             int delay)
 293 {
 294         if (delay > 1000)
 295                 mod_delayed_work(system_freezable_power_efficient_wq,
 296                                  &tz->poll_queue,
 297                                  round_jiffies(msecs_to_jiffies(delay)));
 298         else if (delay)
 299                 mod_delayed_work(system_freezable_power_efficient_wq,
 300                                  &tz->poll_queue,
 301                                  msecs_to_jiffies(delay));
 302         else
 303                 cancel_delayed_work(&tz->poll_queue);
 304 }
 305
 306 static inline bool should_stop_polling(struct thermal_zone_device *tz)
 307 {
 308         return !thermal_zone_device_is_enabled(tz);
 309 }
 310
 311 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 312 {
 313         bool stop;
 314
 315         stop = should_stop_polling(tz);
 316
 317         mutex_lock(&tz->lock);
 318
 319         if (!stop && tz->passive)
 320                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 321         else if (!stop && tz->polling_delay)
 322                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 323         else
 324                 thermal_zone_device_set_polling(tz, 0);
 325
 326         mutex_unlock(&tz->lock);
 327 }
 328
 329 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 330 {
 331         tz->governor ? tz->governor->throttle(tz, trip) :
 332                        def_governor->throttle(tz, trip);
 333 }
 334
 335 /**
 336  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 337  * @work: work_struct associated with the emergency poweroff function
 338  *
 339  * This function is called in very critical situations to force
 340  * a kernel poweroff after a configurable timeout value.
 341  */
 342 static void thermal_emergency_poweroff_func(struct work_struct *work)
 343 {
 344         /*
 345          * We have reached here after the emergency thermal shutdown
 346          * Waiting period has expired. This means orderly_poweroff has
 347          * not been able to shut off the system for some reason.
 348          * Try to shut down the system immediately using kernel_power_off
 349          * if populated
 350          */
 351         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 352         kernel_power_off();
 353
 354         /*
 355          * Worst of the worst case trigger emergency restart
 356          */
 357         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 358         emergency_restart();
 359 }
 360
 361 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 362                             thermal_emergency_poweroff_func);
 363
 364 /**
 365  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 366  *
 367  * This may be called from any critical situation to trigger a system shutdown
 368  * after a known period of time. By default this is not scheduled.
 369  */
 370 static void thermal_emergency_poweroff(void)
 371 {
 372         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 373         /*
 374          * poweroff_delay_ms must be a carefully profiled positive value.
 375          * Its a must for thermal_emergency_poweroff_work to be scheduled
 376          */
 377         if (poweroff_delay_ms <= 0)
 378                 return;
 379         schedule_delayed_work(&thermal_emergency_poweroff_work,
 380                               msecs_to_jiffies(poweroff_delay_ms));
 381 }
 382
 383 static void handle_critical_trips(struct thermal_zone_device *tz,
 384                                   int trip, enum thermal_trip_type trip_type)
 385 {
 386         int trip_temp;
 387
 388         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 389
 390         /* If we have not crossed the trip_temp, we do not care. */
 391         if (trip_temp <= 0 || tz->temperature < trip_temp)
 392                 return;
 393
 394         trace_thermal_zone_trip(tz, trip, trip_type);
 395
 396         if (tz->ops->notify)
 397                 tz->ops->notify(tz, trip, trip_type);
 398
 399         if (trip_type == THERMAL_TRIP_CRITICAL) {
 400                 dev_emerg(&tz->device,
 401                           "critical temperature reached (%d C), shutting down\n",
 402                           tz->temperature / 1000);
 403                 mutex_lock(&poweroff_lock);
 404                 if (!power_off_triggered) {
 405                         /*
 406                          * Queue a backup emergency shutdown in the event of
 407                          * orderly_poweroff failure
 408                          */
 409                         thermal_emergency_poweroff();
 410                         orderly_poweroff(true);
 411                         power_off_triggered = true;
 412                 }
 413                 mutex_unlock(&poweroff_lock);
 414         }
 415 }
 416
 417 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 418 {
 419         enum thermal_trip_type type;
 420         int trip_temp, hyst = 0;
 421
 422         /* Ignore disabled trip points */
 423         if (test_bit(trip, &tz->trips_disabled))
 424                 return;
 425
 426         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 427         tz->ops->get_trip_type(tz, trip, &type);
 428         if (tz->ops->get_trip_hyst)
 429                 tz->ops->get_trip_hyst(tz, trip, &hyst);
 430
 431         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 432                 if (tz->last_temperature < trip_temp &&
 433                     tz->temperature >= trip_temp)
 434                         thermal_notify_tz_trip_up(tz->id, trip);
 435                 if (tz->last_temperature >= trip_temp &&
 436                     tz->temperature < (trip_temp - hyst))
 437                         thermal_notify_tz_trip_down(tz->id, trip);
 438         }
 439
 440         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 441                 handle_critical_trips(tz, trip, type);
 442         else
 443                 handle_non_critical_trips(tz, trip);
 444         /*
 445          * Alright, we handled this trip successfully.
 446          * So, start monitoring again.
 447          */
 448         monitor_thermal_zone(tz);
 449 }
 450
 451 static void update_temperature(struct thermal_zone_device *tz)
 452 {
 453         int temp, ret;
 454
 455         ret = thermal_zone_get_temp(tz, &temp);
 456         if (ret) {
 457                 if (ret != -EAGAIN)
 458                         dev_warn(&tz->device,
 459                                  "failed to read out thermal zone (%d)\n",
 460                                  ret);
 461                 return;
 462         }
 463
 464         mutex_lock(&tz->lock);
 465         tz->last_temperature = tz->temperature;
 466         tz->temperature = temp;
 467         mutex_unlock(&tz->lock);
 468
 469         trace_thermal_temperature(tz);
 470
 471         thermal_genl_sampling_temp(tz->id, temp);
 472 }
 473
 474 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 475 {
 476         struct thermal_instance *pos;
 477         tz->temperature = THERMAL_TEMP_INVALID;
 478         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 479                 pos->initialized = false;
 480 }
 481
 482 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 483 {
 484         tz->passive = 0;
 485         thermal_zone_device_init(tz);
 486 }
 487
 488 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 489                                         enum thermal_device_mode mode)
 490 {
 491         int ret = 0;
 492
 493         mutex_lock(&tz->lock);
 494
 495         /* do nothing if mode isn't changing */
 496         if (mode == tz->mode) {
 497                 mutex_unlock(&tz->lock);
 498
 499                 return ret;
 500         }
 501
 502         if (tz->ops->change_mode)
 503                 ret = tz->ops->change_mode(tz, mode);
 504
 505         if (!ret)
 506                 tz->mode = mode;
 507
 508         mutex_unlock(&tz->lock);
 509
 510         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 511
 512         if (mode == THERMAL_DEVICE_ENABLED)
 513                 thermal_notify_tz_enable(tz->id);
 514         else
 515                 thermal_notify_tz_disable(tz->id);
 516
 517         return ret;
 518 }
 519
 520 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 521 {
 522         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 523 }
 524 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 525
 526 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 527 {
 528         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 529 }
 530 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 531
 532 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 533 {
 534         enum thermal_device_mode mode;
 535
 536         mutex_lock(&tz->lock);
 537
 538         mode = tz->mode;
 539
 540         mutex_unlock(&tz->lock);
 541
 542         return mode == THERMAL_DEVICE_ENABLED;
 543 }
 544
 545 void thermal_zone_device_update(struct thermal_zone_device *tz,
 546                                 enum thermal_notify_event event)
 547 {
 548         int count;
 549
 550         if (should_stop_polling(tz))
 551                 return;
 552
 553         if (atomic_read(&in_suspend))
 554                 return;
 555
 556         if (!tz->ops->get_temp)
 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 /*
 597  * Power actor section: interface to power actors to estimate power
 598  *
 599  * Set of functions used to interact to cooling devices that know
 600  * how to estimate their devices power consumption.
 601  */
 602
 603 /**
 604  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 605  * @cdev:       pointer to &thermal_cooling_device
 606  * @max_power:  pointer in which to store the maximum power
 607  *
 608  * Calculate the maximum power consumption in milliwats that the
 609  * cooling device can currently consume and store it in @max_power.
 610  *
 611  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 612  * power_actor API or -E* on other error.
 613  */
 614 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 615                               u32 *max_power)
 616 {
 617         if (!cdev_is_power_actor(cdev))
 618                 return -EINVAL;
 619
 620         return cdev->ops->state2power(cdev, 0, max_power);
 621 }
 622
 623 /**
 624  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 625  * @cdev:       pointer to &thermal_cooling_device
 626  * @min_power:  pointer in which to store the minimum power
 627  *
 628  * Calculate the minimum power consumption in milliwatts that the
 629  * cooling device can currently consume and store it in @min_power.
 630  *
 631  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 632  * power_actor API or -E* on other error.
 633  */
 634 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 635                               u32 *min_power)
 636 {
 637         unsigned long max_state;
 638         int ret;
 639
 640         if (!cdev_is_power_actor(cdev))
 641                 return -EINVAL;
 642
 643         ret = cdev->ops->get_max_state(cdev, &max_state);
 644         if (ret)
 645                 return ret;
 646
 647         return cdev->ops->state2power(cdev, max_state, min_power);
 648 }
 649
 650 /**
 651  * power_actor_set_power() - limit the maximum power a cooling device consumes
 652  * @cdev:       pointer to &thermal_cooling_device
 653  * @instance:   thermal instance to update
 654  * @power:      the power in milliwatts
 655  *
 656  * Set the cooling device to consume at most @power milliwatts. The limit is
 657  * expected to be a cap at the maximum power consumption.
 658  *
 659  * Return: 0 on success, -EINVAL if the cooling device does not
 660  * implement the power actor API or -E* for other failures.
 661  */
 662 int power_actor_set_power(struct thermal_cooling_device *cdev,
 663                           struct thermal_instance *instance, u32 power)
 664 {
 665         unsigned long state;
 666         int ret;
 667
 668         if (!cdev_is_power_actor(cdev))
 669                 return -EINVAL;
 670
 671         ret = cdev->ops->power2state(cdev, power, &state);
 672         if (ret)
 673                 return ret;
 674
 675         instance->target = state;
 676         mutex_lock(&cdev->lock);
 677         cdev->updated = false;
 678         mutex_unlock(&cdev->lock);
 679         thermal_cdev_update(cdev);
 680
 681         return 0;
 682 }
 683
 684 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 685                                           const char *cdev_type, size_t size)
 686 {
 687         struct thermal_cooling_device *cdev = NULL;
 688
 689         mutex_lock(&thermal_list_lock);
 690         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 691                 /* skip non matching cdevs */
 692                 if (strncmp(cdev_type, cdev->type, size))
 693                         continue;
 694
 695                 /* re binding the exception matching the type pattern */
 696                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 697                                                  THERMAL_NO_LIMIT,
 698                                                  THERMAL_NO_LIMIT,
 699                                                  THERMAL_WEIGHT_DEFAULT);
 700         }
 701         mutex_unlock(&thermal_list_lock);
 702 }
 703
 704 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 705                               void *data)
 706 {
 707         struct thermal_governor *gov;
 708         int ret = 0;
 709
 710         mutex_lock(&thermal_governor_lock);
 711         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 712                 ret = cb(gov, data);
 713                 if (ret)
 714                         break;
 715         }
 716         mutex_unlock(&thermal_governor_lock);
 717
 718         return ret;
 719 }
 720
 721 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 722                                               void *), void *data)
 723 {
 724         struct thermal_cooling_device *cdev;
 725         int ret = 0;
 726
 727         mutex_lock(&thermal_list_lock);
 728         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 729                 ret = cb(cdev, data);
 730                 if (ret)
 731                         break;
 732         }
 733         mutex_unlock(&thermal_list_lock);
 734
 735         return ret;
 736 }
 737
 738 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 739                           void *data)
 740 {
 741         struct thermal_zone_device *tz;
 742         int ret = 0;
 743
 744         mutex_lock(&thermal_list_lock);
 745         list_for_each_entry(tz, &thermal_tz_list, node) {
 746                 ret = cb(tz, data);
 747                 if (ret)
 748                         break;
 749         }
 750         mutex_unlock(&thermal_list_lock);
 751
 752         return ret;
 753 }
 754
 755 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 756 {
 757         struct thermal_zone_device *tz, *match = NULL;
 758
 759         mutex_lock(&thermal_list_lock);
 760         list_for_each_entry(tz, &thermal_tz_list, node) {
 761                 if (tz->id == id) {
 762                         match = tz;
 763                         break;
 764                 }
 765         }
 766         mutex_unlock(&thermal_list_lock);
 767
 768         return match;
 769 }
 770
 771 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 772                                           const char *cdev_type, size_t size)
 773 {
 774         struct thermal_cooling_device *cdev = NULL;
 775
 776         mutex_lock(&thermal_list_lock);
 777         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 778                 /* skip non matching cdevs */
 779                 if (strncmp(cdev_type, cdev->type, size))
 780                         continue;
 781                 /* unbinding the exception matching the type pattern */
 782                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 783                                                    cdev);
 784         }
 785         mutex_unlock(&thermal_list_lock);
 786 }
 787
 788 /*
 789  * Device management section: cooling devices, zones devices, and binding
 790  *
 791  * Set of functions provided by the thermal core for:
 792  * - cooling devices lifecycle: registration, unregistration,
 793  *                              binding, and unbinding.
 794  * - thermal zone devices lifecycle: registration, unregistration,
 795  *                                   binding, and unbinding.
 796  */
 797
 798 /**
 799  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 800  * @tz:         pointer to struct thermal_zone_device
 801  * @trip:       indicates which trip point the cooling devices is
 802  *              associated with in this thermal zone.
 803  * @cdev:       pointer to struct thermal_cooling_device
 804  * @upper:      the Maximum cooling state for this trip point.
 805  *              THERMAL_NO_LIMIT means no upper limit,
 806  *              and the cooling device can be in max_state.
 807  * @lower:      the Minimum cooling state can be used for this trip point.
 808  *              THERMAL_NO_LIMIT means no lower limit,
 809  *              and the cooling device can be in cooling state 0.
 810  * @weight:     The weight of the cooling device to be bound to the
 811  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 812  *              default value
 813  *
 814  * This interface function bind a thermal cooling device to the certain trip
 815  * point of a thermal zone device.
 816  * This function is usually called in the thermal zone device .bind callback.
 817  *
 818  * Return: 0 on success, the proper error value otherwise.
 819  */
 820 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 821                                      int trip,
 822                                      struct thermal_cooling_device *cdev,
 823                                      unsigned long upper, unsigned long lower,
 824                                      unsigned int weight)
 825 {
 826         struct thermal_instance *dev;
 827         struct thermal_instance *pos;
 828         struct thermal_zone_device *pos1;
 829         struct thermal_cooling_device *pos2;
 830         unsigned long max_state;
 831         int result, ret;
 832
 833         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 834                 return -EINVAL;
 835
 836         list_for_each_entry(pos1, &thermal_tz_list, node) {
 837                 if (pos1 == tz)
 838                         break;
 839         }
 840         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 841                 if (pos2 == cdev)
 842                         break;
 843         }
 844
 845         if (tz != pos1 || cdev != pos2)
 846                 return -EINVAL;
 847
 848         ret = cdev->ops->get_max_state(cdev, &max_state);
 849         if (ret)
 850                 return ret;
 851
 852         /* lower default 0, upper default max_state */
 853         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 854         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 855
 856         if (lower > upper || upper > max_state)
 857                 return -EINVAL;
 858
 859         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 860         if (!dev)
 861                 return -ENOMEM;
 862         dev->tz = tz;
 863         dev->cdev = cdev;
 864         dev->trip = trip;
 865         dev->upper = upper;
 866         dev->lower = lower;
 867         dev->target = THERMAL_NO_TARGET;
 868         dev->weight = weight;
 869
 870         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 871         if (result < 0)
 872                 goto free_mem;
 873
 874         dev->id = result;
 875         sprintf(dev->name, "cdev%d", dev->id);
 876         result =
 877             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 878         if (result)
 879                 goto release_ida;
 880
 881         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 882         sysfs_attr_init(&dev->attr.attr);
 883         dev->attr.attr.name = dev->attr_name;
 884         dev->attr.attr.mode = 0444;
 885         dev->attr.show = trip_point_show;
 886         result = device_create_file(&tz->device, &dev->attr);
 887         if (result)
 888                 goto remove_symbol_link;
 889
 890         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 891         sysfs_attr_init(&dev->weight_attr.attr);
 892         dev->weight_attr.attr.name = dev->weight_attr_name;
 893         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 894         dev->weight_attr.show = weight_show;
 895         dev->weight_attr.store = weight_store;
 896         result = device_create_file(&tz->device, &dev->weight_attr);
 897         if (result)
 898                 goto remove_trip_file;
 899
 900         mutex_lock(&tz->lock);
 901         mutex_lock(&cdev->lock);
 902         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 903                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 904                         result = -EEXIST;
 905                         break;
 906                 }
 907         if (!result) {
 908                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 909                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 910                 atomic_set(&tz->need_update, 1);
 911         }
 912         mutex_unlock(&cdev->lock);
 913         mutex_unlock(&tz->lock);
 914
 915         if (!result)
 916                 return 0;
 917
 918         device_remove_file(&tz->device, &dev->weight_attr);
 919 remove_trip_file:
 920         device_remove_file(&tz->device, &dev->attr);
 921 remove_symbol_link:
 922         sysfs_remove_link(&tz->device.kobj, dev->name);
 923 release_ida:
 924         ida_simple_remove(&tz->ida, dev->id);
 925 free_mem:
 926         kfree(dev);
 927         return result;
 928 }
 929 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 930
 931 /**
 932  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 933  *                                        thermal zone.
 934  * @tz:         pointer to a struct thermal_zone_device.
 935  * @trip:       indicates which trip point the cooling devices is
 936  *              associated with in this thermal zone.
 937  * @cdev:       pointer to a struct thermal_cooling_device.
 938  *
 939  * This interface function unbind a thermal cooling device from the certain
 940  * trip point of a thermal zone device.
 941  * This function is usually called in the thermal zone device .unbind callback.
 942  *
 943  * Return: 0 on success, the proper error value otherwise.
 944  */
 945 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 946                                        int trip,
 947                                        struct thermal_cooling_device *cdev)
 948 {
 949         struct thermal_instance *pos, *next;
 950
 951         mutex_lock(&tz->lock);
 952         mutex_lock(&cdev->lock);
 953         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 954                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 955                         list_del(&pos->tz_node);
 956                         list_del(&pos->cdev_node);
 957                         mutex_unlock(&cdev->lock);
 958                         mutex_unlock(&tz->lock);
 959                         goto unbind;
 960                 }
 961         }
 962         mutex_unlock(&cdev->lock);
 963         mutex_unlock(&tz->lock);
 964
 965         return -ENODEV;
 966
 967 unbind:
 968         device_remove_file(&tz->device, &pos->weight_attr);
 969         device_remove_file(&tz->device, &pos->attr);
 970         sysfs_remove_link(&tz->device.kobj, pos->name);
 971         ida_simple_remove(&tz->ida, pos->id);
 972         kfree(pos);
 973         return 0;
 974 }
 975 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 976
 977 static void thermal_release(struct device *dev)
 978 {
 979         struct thermal_zone_device *tz;
 980         struct thermal_cooling_device *cdev;
 981
 982         if (!strncmp(dev_name(dev), "thermal_zone",
 983                      sizeof("thermal_zone") - 1)) {
 984                 tz = to_thermal_zone(dev);
 985                 thermal_zone_destroy_device_groups(tz);
 986                 kfree(tz);
 987         } else if (!strncmp(dev_name(dev), "cooling_device",
 988                             sizeof("cooling_device") - 1)) {
 989                 cdev = to_cooling_device(dev);
 990                 kfree(cdev);
 991         }
 992 }
 993
 994 static struct class thermal_class = {
 995         .name = "thermal",
 996         .dev_release = thermal_release,
 997 };
 998
 999 static inline
1000 void print_bind_err_msg(struct thermal_zone_device *tz,
1001                         struct thermal_cooling_device *cdev, int ret)
1002 {
1003         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
1004                 tz->type, cdev->type, ret);
1005 }
1006
1007 static void __bind(struct thermal_zone_device *tz, int mask,
1008                    struct thermal_cooling_device *cdev,
1009                    unsigned long *limits,
1010                    unsigned int weight)
1011 {
1012         int i, ret;
1013
1014         for (i = 0; i < tz->trips; i++) {
1015                 if (mask & (1 << i)) {
1016                         unsigned long upper, lower;
1017
1018                         upper = THERMAL_NO_LIMIT;
1019                         lower = THERMAL_NO_LIMIT;
1020                         if (limits) {
1021                                 lower = limits[i * 2];
1022                                 upper = limits[i * 2 + 1];
1023                         }
1024                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
1025                                                                upper, lower,
1026                                                                weight);
1027                         if (ret)
1028                                 print_bind_err_msg(tz, cdev, ret);
1029                 }
1030         }
1031 }
1032
1033 static void bind_cdev(struct thermal_cooling_device *cdev)
1034 {
1035         int i, ret;
1036         const struct thermal_zone_params *tzp;
1037         struct thermal_zone_device *pos = NULL;
1038
1039         mutex_lock(&thermal_list_lock);
1040
1041         list_for_each_entry(pos, &thermal_tz_list, node) {
1042                 if (!pos->tzp && !pos->ops->bind)
1043                         continue;
1044
1045                 if (pos->ops->bind) {
1046                         ret = pos->ops->bind(pos, cdev);
1047                         if (ret)
1048                                 print_bind_err_msg(pos, cdev, ret);
1049                         continue;
1050                 }
1051
1052                 tzp = pos->tzp;
1053                 if (!tzp || !tzp->tbp)
1054                         continue;
1055
1056                 for (i = 0; i < tzp->num_tbps; i++) {
1057                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1058                                 continue;
1059                         if (tzp->tbp[i].match(pos, cdev))
1060                                 continue;
1061                         tzp->tbp[i].cdev = cdev;
1062                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
1063                                tzp->tbp[i].binding_limits,
1064                                tzp->tbp[i].weight);
1065                 }
1066         }
1067
1068         mutex_unlock(&thermal_list_lock);
1069 }
1070
1071 /**
1072  * __thermal_cooling_device_register() - register a new thermal cooling device
1073  * @np:         a pointer to a device tree node.
1074  * @type:       the thermal cooling device type.
1075  * @devdata:    device private data.
1076  * @ops:                standard thermal cooling devices callbacks.
1077  *
1078  * This interface function adds a new thermal cooling device (fan/processor/...)
1079  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1080  * to all the thermal zone devices registered at the same time.
1081  * It also gives the opportunity to link the cooling device to a device tree
1082  * node, so that it can be bound to a thermal zone created out of device tree.
1083  *
1084  * Return: a pointer to the created struct thermal_cooling_device or an
1085  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1086  */
1087 static struct thermal_cooling_device *
1088 __thermal_cooling_device_register(struct device_node *np,
1089                                   const char *type, void *devdata,
1090                                   const struct thermal_cooling_device_ops *ops)
1091 {
1092         struct thermal_cooling_device *cdev;
1093         struct thermal_zone_device *pos = NULL;
1094         int result;
1095
1096         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1097                 return ERR_PTR(-EINVAL);
1098
1099         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1100             !ops->set_cur_state)
1101                 return ERR_PTR(-EINVAL);
1102
1103         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1104         if (!cdev)
1105                 return ERR_PTR(-ENOMEM);
1106
1107         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1108         if (result < 0) {
1109                 kfree(cdev);
1110                 return ERR_PTR(result);
1111         }
1112
1113         cdev->id = result;
1114         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1115         mutex_init(&cdev->lock);
1116         INIT_LIST_HEAD(&cdev->thermal_instances);
1117         cdev->np = np;
1118         cdev->ops = ops;
1119         cdev->updated = false;
1120         cdev->device.class = &thermal_class;
1121         cdev->devdata = devdata;
1122         thermal_cooling_device_setup_sysfs(cdev);
1123         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1124         result = device_register(&cdev->device);
1125         if (result) {
1126                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1127                 put_device(&cdev->device);
1128                 return ERR_PTR(result);
1129         }
1130
1131         /* Add 'this' new cdev to the global cdev list */
1132         mutex_lock(&thermal_list_lock);
1133         list_add(&cdev->node, &thermal_cdev_list);
1134         mutex_unlock(&thermal_list_lock);
1135
1136         /* Update binding information for 'this' new cdev */
1137         bind_cdev(cdev);
1138
1139         mutex_lock(&thermal_list_lock);
1140         list_for_each_entry(pos, &thermal_tz_list, node)
1141                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1142                         thermal_zone_device_update(pos,
1143                                                    THERMAL_EVENT_UNSPECIFIED);
1144         mutex_unlock(&thermal_list_lock);
1145
1146         return cdev;
1147 }
1148
1149 /**
1150  * thermal_cooling_device_register() - register a new thermal cooling device
1151  * @type:       the thermal cooling device type.
1152  * @devdata:    device private data.
1153  * @ops:                standard thermal cooling devices callbacks.
1154  *
1155  * This interface function adds a new thermal cooling device (fan/processor/...)
1156  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1157  * to all the thermal zone devices registered at the same time.
1158  *
1159  * Return: a pointer to the created struct thermal_cooling_device or an
1160  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1161  */
1162 struct thermal_cooling_device *
1163 thermal_cooling_device_register(const char *type, void *devdata,
1164                                 const struct thermal_cooling_device_ops *ops)
1165 {
1166         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1167 }
1168 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1169
1170 /**
1171  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1172  * @np:         a pointer to a device tree node.
1173  * @type:       the thermal cooling device type.
1174  * @devdata:    device private data.
1175  * @ops:                standard thermal cooling devices callbacks.
1176  *
1177  * This function will register a cooling device with device tree node reference.
1178  * This interface function adds a new thermal cooling device (fan/processor/...)
1179  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1180  * to all the thermal zone devices registered at the same time.
1181  *
1182  * Return: a pointer to the created struct thermal_cooling_device or an
1183  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1184  */
1185 struct thermal_cooling_device *
1186 thermal_of_cooling_device_register(struct device_node *np,
1187                                    const char *type, void *devdata,
1188                                    const struct thermal_cooling_device_ops *ops)
1189 {
1190         return __thermal_cooling_device_register(np, type, devdata, ops);
1191 }
1192 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1193
1194 static void thermal_cooling_device_release(struct device *dev, void *res)
1195 {
1196         thermal_cooling_device_unregister(
1197                                 *(struct thermal_cooling_device **)res);
1198 }
1199
1200 /**
1201  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1202  *                                             device
1203  * @dev:        a valid struct device pointer of a sensor device.
1204  * @np:         a pointer to a device tree node.
1205  * @type:       the thermal cooling device type.
1206  * @devdata:    device private data.
1207  * @ops:        standard thermal cooling devices callbacks.
1208  *
1209  * This function will register a cooling device with device tree node reference.
1210  * This interface function adds a new thermal cooling device (fan/processor/...)
1211  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1212  * to all the thermal zone devices registered at the same time.
1213  *
1214  * Return: a pointer to the created struct thermal_cooling_device or an
1215  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1216  */
1217 struct thermal_cooling_device *
1218 devm_thermal_of_cooling_device_register(struct device *dev,
1219                                 struct device_node *np,
1220                                 char *type, void *devdata,
1221                                 const struct thermal_cooling_device_ops *ops)
1222 {
1223         struct thermal_cooling_device **ptr, *tcd;
1224
1225         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1226                            GFP_KERNEL);
1227         if (!ptr)
1228                 return ERR_PTR(-ENOMEM);
1229
1230         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1231         if (IS_ERR(tcd)) {
1232                 devres_free(ptr);
1233                 return tcd;
1234         }
1235
1236         *ptr = tcd;
1237         devres_add(dev, ptr);
1238
1239         return tcd;
1240 }
1241 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1242
1243 static void __unbind(struct thermal_zone_device *tz, int mask,
1244                      struct thermal_cooling_device *cdev)
1245 {
1246         int i;
1247
1248         for (i = 0; i < tz->trips; i++)
1249                 if (mask & (1 << i))
1250                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1251 }
1252
1253 /**
1254  * thermal_cooling_device_unregister - removes a thermal cooling device
1255  * @cdev:       the thermal cooling device to remove.
1256  *
1257  * thermal_cooling_device_unregister() must be called when a registered
1258  * thermal cooling device is no longer needed.
1259  */
1260 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1261 {
1262         int i;
1263         const struct thermal_zone_params *tzp;
1264         struct thermal_zone_device *tz;
1265         struct thermal_cooling_device *pos = NULL;
1266
1267         if (!cdev)
1268                 return;
1269
1270         mutex_lock(&thermal_list_lock);
1271         list_for_each_entry(pos, &thermal_cdev_list, node)
1272                 if (pos == cdev)
1273                         break;
1274         if (pos != cdev) {
1275                 /* thermal cooling device not found */
1276                 mutex_unlock(&thermal_list_lock);
1277                 return;
1278         }
1279         list_del(&cdev->node);
1280
1281         /* Unbind all thermal zones associated with 'this' cdev */
1282         list_for_each_entry(tz, &thermal_tz_list, node) {
1283                 if (tz->ops->unbind) {
1284                         tz->ops->unbind(tz, cdev);
1285                         continue;
1286                 }
1287
1288                 if (!tz->tzp || !tz->tzp->tbp)
1289                         continue;
1290
1291                 tzp = tz->tzp;
1292                 for (i = 0; i < tzp->num_tbps; i++) {
1293                         if (tzp->tbp[i].cdev == cdev) {
1294                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1295                                 tzp->tbp[i].cdev = NULL;
1296                         }
1297                 }
1298         }
1299
1300         mutex_unlock(&thermal_list_lock);
1301
1302         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1303         device_del(&cdev->device);
1304         thermal_cooling_device_destroy_sysfs(cdev);
1305         put_device(&cdev->device);
1306 }
1307 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1308
1309 static void bind_tz(struct thermal_zone_device *tz)
1310 {
1311         int i, ret;
1312         struct thermal_cooling_device *pos = NULL;
1313         const struct thermal_zone_params *tzp = tz->tzp;
1314
1315         if (!tzp && !tz->ops->bind)
1316                 return;
1317
1318         mutex_lock(&thermal_list_lock);
1319
1320         /* If there is ops->bind, try to use ops->bind */
1321         if (tz->ops->bind) {
1322                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1323                         ret = tz->ops->bind(tz, pos);
1324                         if (ret)
1325                                 print_bind_err_msg(tz, pos, ret);
1326                 }
1327                 goto exit;
1328         }
1329
1330         if (!tzp || !tzp->tbp)
1331                 goto exit;
1332
1333         list_for_each_entry(pos, &thermal_cdev_list, node) {
1334                 for (i = 0; i < tzp->num_tbps; i++) {
1335                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1336                                 continue;
1337                         if (tzp->tbp[i].match(tz, pos))
1338                                 continue;
1339                         tzp->tbp[i].cdev = pos;
1340                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1341                                tzp->tbp[i].binding_limits,
1342                                tzp->tbp[i].weight);
1343                 }
1344         }
1345 exit:
1346         mutex_unlock(&thermal_list_lock);
1347 }
1348
1349 /**
1350  * thermal_zone_device_register() - register a new thermal zone device
1351  * @type:       the thermal zone device type
1352  * @trips:      the number of trip points the thermal zone support
1353  * @mask:       a bit string indicating the writeablility of trip points
1354  * @devdata:    private device data
1355  * @ops:        standard thermal zone device callbacks
1356  * @tzp:        thermal zone platform parameters
1357  * @passive_delay: number of milliseconds to wait between polls when
1358  *                 performing passive cooling
1359  * @polling_delay: number of milliseconds to wait between polls when checking
1360  *                 whether trip points have been crossed (0 for interrupt
1361  *                 driven systems)
1362  *
1363  * This interface function adds a new thermal zone device (sensor) to
1364  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1365  * thermal cooling devices registered at the same time.
1366  * thermal_zone_device_unregister() must be called when the device is no
1367  * longer needed. The passive cooling depends on the .get_trend() return value.
1368  *
1369  * Return: a pointer to the created struct thermal_zone_device or an
1370  * in case of error, an ERR_PTR. Caller must check return value with
1371  * IS_ERR*() helpers.
1372  */
1373 struct thermal_zone_device *
1374 thermal_zone_device_register(const char *type, int trips, int mask,
1375                              void *devdata, struct thermal_zone_device_ops *ops,
1376                              struct thermal_zone_params *tzp, int passive_delay,
1377                              int polling_delay)
1378 {
1379         struct thermal_zone_device *tz;
1380         enum thermal_trip_type trip_type;
1381         int trip_temp;
1382         int id;
1383         int result;
1384         int count;
1385         struct thermal_governor *governor;
1386
1387         if (!type || strlen(type) == 0) {
1388                 pr_err("Error: No thermal zone type defined\n");
1389                 return ERR_PTR(-EINVAL);
1390         }
1391
1392         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1393                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1394                        type, THERMAL_NAME_LENGTH);
1395                 return ERR_PTR(-EINVAL);
1396         }
1397
1398         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1399                 pr_err("Error: Incorrect number of thermal trips\n");
1400                 return ERR_PTR(-EINVAL);
1401         }
1402
1403         if (!ops) {
1404                 pr_err("Error: Thermal zone device ops not defined\n");
1405                 return ERR_PTR(-EINVAL);
1406         }
1407
1408         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1409                 return ERR_PTR(-EINVAL);
1410
1411         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1412         if (!tz)
1413                 return ERR_PTR(-ENOMEM);
1414
1415         INIT_LIST_HEAD(&tz->thermal_instances);
1416         ida_init(&tz->ida);
1417         mutex_init(&tz->lock);
1418         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1419         if (id < 0) {
1420                 result = id;
1421                 goto free_tz;
1422         }
1423
1424         tz->id = id;
1425         strlcpy(tz->type, type, sizeof(tz->type));
1426         tz->ops = ops;
1427         tz->tzp = tzp;
1428         tz->device.class = &thermal_class;
1429         tz->devdata = devdata;
1430         tz->trips = trips;
1431         tz->passive_delay = passive_delay;
1432         tz->polling_delay = polling_delay;
1433
1434         /* sys I/F */
1435         /* Add nodes that are always present via .groups */
1436         result = thermal_zone_create_device_groups(tz, mask);
1437         if (result)
1438                 goto remove_id;
1439
1440         /* A new thermal zone needs to be updated anyway. */
1441         atomic_set(&tz->need_update, 1);
1442
1443         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1444         result = device_register(&tz->device);
1445         if (result)
1446                 goto release_device;
1447
1448         for (count = 0; count < trips; count++) {
1449                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1450                         set_bit(count, &tz->trips_disabled);
1451                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1452                         set_bit(count, &tz->trips_disabled);
1453                 /* Check for bogus trip points */
1454                 if (trip_temp == 0)
1455                         set_bit(count, &tz->trips_disabled);
1456         }
1457
1458         /* Update 'this' zone's governor information */
1459         mutex_lock(&thermal_governor_lock);
1460
1461         if (tz->tzp)
1462                 governor = __find_governor(tz->tzp->governor_name);
1463         else
1464                 governor = def_governor;
1465
1466         result = thermal_set_governor(tz, governor);
1467         if (result) {
1468                 mutex_unlock(&thermal_governor_lock);
1469                 goto unregister;
1470         }
1471
1472         mutex_unlock(&thermal_governor_lock);
1473
1474         if (!tz->tzp || !tz->tzp->no_hwmon) {
1475                 result = thermal_add_hwmon_sysfs(tz);
1476                 if (result)
1477                         goto unregister;
1478         }
1479
1480         mutex_lock(&thermal_list_lock);
1481         list_add_tail(&tz->node, &thermal_tz_list);
1482         mutex_unlock(&thermal_list_lock);
1483
1484         /* Bind cooling devices for this zone */
1485         bind_tz(tz);
1486
1487         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1488
1489         thermal_zone_device_reset(tz);
1490         /* Update the new thermal zone and mark it as already updated. */
1491         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1492                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1493
1494         thermal_notify_tz_create(tz->id, tz->type);
1495
1496         return tz;
1497
1498 unregister:
1499         device_del(&tz->device);
1500 release_device:
1501         put_device(&tz->device);
1502         tz = NULL;
1503 remove_id:
1504         ida_simple_remove(&thermal_tz_ida, id);
1505 free_tz:
1506         kfree(tz);
1507         return ERR_PTR(result);
1508 }
1509 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1510
1511 /**
1512  * thermal_device_unregister - removes the registered thermal zone device
1513  * @tz: the thermal zone device to remove
1514  */
1515 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1516 {
1517         int i, tz_id;
1518         const struct thermal_zone_params *tzp;
1519         struct thermal_cooling_device *cdev;
1520         struct thermal_zone_device *pos = NULL;
1521
1522         if (!tz)
1523                 return;
1524
1525         tzp = tz->tzp;
1526         tz_id = tz->id;
1527
1528         mutex_lock(&thermal_list_lock);
1529         list_for_each_entry(pos, &thermal_tz_list, node)
1530                 if (pos == tz)
1531                         break;
1532         if (pos != tz) {
1533                 /* thermal zone device not found */
1534                 mutex_unlock(&thermal_list_lock);
1535                 return;
1536         }
1537         list_del(&tz->node);
1538
1539         /* Unbind all cdevs associated with 'this' thermal zone */
1540         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1541                 if (tz->ops->unbind) {
1542                         tz->ops->unbind(tz, cdev);
1543                         continue;
1544                 }
1545
1546                 if (!tzp || !tzp->tbp)
1547                         break;
1548
1549                 for (i = 0; i < tzp->num_tbps; i++) {
1550                         if (tzp->tbp[i].cdev == cdev) {
1551                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1552                                 tzp->tbp[i].cdev = NULL;
1553                         }
1554                 }
1555         }
1556
1557         mutex_unlock(&thermal_list_lock);
1558
1559         cancel_delayed_work_sync(&tz->poll_queue);
1560
1561         thermal_set_governor(tz, NULL);
1562
1563         thermal_remove_hwmon_sysfs(tz);
1564         ida_simple_remove(&thermal_tz_ida, tz->id);
1565         ida_destroy(&tz->ida);
1566         mutex_destroy(&tz->lock);
1567         device_unregister(&tz->device);
1568
1569         thermal_notify_tz_delete(tz_id);
1570 }
1571 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1572
1573 /**
1574  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1575  * @name: thermal zone name to fetch the temperature
1576  *
1577  * When only one zone is found with the passed name, returns a reference to it.
1578  *
1579  * Return: On success returns a reference to an unique thermal zone with
1580  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1581  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1582  */
1583 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1584 {
1585         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1586         unsigned int found = 0;
1587
1588         if (!name)
1589                 goto exit;
1590
1591         mutex_lock(&thermal_list_lock);
1592         list_for_each_entry(pos, &thermal_tz_list, node)
1593                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1594                         found++;
1595                         ref = pos;
1596                 }
1597         mutex_unlock(&thermal_list_lock);
1598
1599         /* nothing has been found, thus an error code for it */
1600         if (found == 0)
1601                 ref = ERR_PTR(-ENODEV);
1602         else if (found > 1)
1603         /* Success only when an unique zone is found */
1604                 ref = ERR_PTR(-EEXIST);
1605
1606 exit:
1607         return ref;
1608 }
1609 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1610
1611 static int thermal_pm_notify(struct notifier_block *nb,
1612                              unsigned long mode, void *_unused)
1613 {
1614         struct thermal_zone_device *tz;
1615
1616         switch (mode) {
1617         case PM_HIBERNATION_PREPARE:
1618         case PM_RESTORE_PREPARE:
1619         case PM_SUSPEND_PREPARE:
1620                 atomic_set(&in_suspend, 1);
1621                 break;
1622         case PM_POST_HIBERNATION:
1623         case PM_POST_RESTORE:
1624         case PM_POST_SUSPEND:
1625                 atomic_set(&in_suspend, 0);
1626                 list_for_each_entry(tz, &thermal_tz_list, node) {
1627                         if (!thermal_zone_device_is_enabled(tz))
1628                                 continue;
1629
1630                         thermal_zone_device_init(tz);
1631                         thermal_zone_device_update(tz,
1632                                                    THERMAL_EVENT_UNSPECIFIED);
1633                 }
1634                 break;
1635         default:
1636                 break;
1637         }
1638         return 0;
1639 }
1640
1641 static struct notifier_block thermal_pm_nb = {
1642         .notifier_call = thermal_pm_notify,
1643 };
1644
1645 static int __init thermal_init(void)
1646 {
1647         int result;
1648
1649         result = thermal_netlink_init();
1650         if (result)
1651                 goto error;
1652
1653         result = thermal_register_governors();
1654         if (result)
1655                 goto error;
1656
1657         result = class_register(&thermal_class);
1658         if (result)
1659                 goto unregister_governors;
1660
1661         result = of_parse_thermal_zones();
1662         if (result)
1663                 goto unregister_class;
1664
1665         result = register_pm_notifier(&thermal_pm_nb);
1666         if (result)
1667                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1668                         result);
1669
1670         return 0;
1671
1672 unregister_class:
1673         class_unregister(&thermal_class);
1674 unregister_governors:
1675         thermal_unregister_governors();
1676 error:
1677         ida_destroy(&thermal_tz_ida);
1678         ida_destroy(&thermal_cdev_ida);
1679         mutex_destroy(&thermal_list_lock);
1680         mutex_destroy(&thermal_governor_lock);
1681         mutex_destroy(&poweroff_lock);
1682         return result;
1683 }
1684 postcore_initcall(thermal_init);