drivers/thermal/thermal_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/module.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <net/netlink.h>
  23 #include <net/genetlink.h>
  24 #include <linux/suspend.h>
  25
  26 #define CREATE_TRACE_POINTS
  27 #include <trace/events/thermal.h>
  28
  29 #include "thermal_core.h"
  30 #include "thermal_hwmon.h"
  31
  32 MODULE_AUTHOR("Zhang Rui");
  33 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  34 MODULE_LICENSE("GPL v2");
  35
  36 static DEFINE_IDA(thermal_tz_ida);
  37 static DEFINE_IDA(thermal_cdev_ida);
  38
  39 static LIST_HEAD(thermal_tz_list);
  40 static LIST_HEAD(thermal_cdev_list);
  41 static LIST_HEAD(thermal_governor_list);
  42
  43 static DEFINE_MUTEX(thermal_list_lock);
  44 static DEFINE_MUTEX(thermal_governor_lock);
  45 static DEFINE_MUTEX(poweroff_lock);
  46
  47 static atomic_t in_suspend;
  48 static bool power_off_triggered;
  49
  50 static struct thermal_governor *def_governor;
  51
  52 /*
  53  * Governor section: set of functions to handle thermal governors
  54  *
  55  * Functions to help in the life cycle of thermal governors within
  56  * the thermal core and by the thermal governor code.
  57  */
  58
  59 static struct thermal_governor *__find_governor(const char *name)
  60 {
  61         struct thermal_governor *pos;
  62
  63         if (!name || !name[0])
  64                 return def_governor;
  65
  66         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  67                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  68                         return pos;
  69
  70         return NULL;
  71 }
  72
  73 /**
  74  * bind_previous_governor() - bind the previous governor of the thermal zone
  75  * @tz:         a valid pointer to a struct thermal_zone_device
  76  * @failed_gov_name:    the name of the governor that failed to register
  77  *
  78  * Register the previous governor of the thermal zone after a new
  79  * governor has failed to be bound.
  80  */
  81 static void bind_previous_governor(struct thermal_zone_device *tz,
  82                                    const char *failed_gov_name)
  83 {
  84         if (tz->governor && tz->governor->bind_to_tz) {
  85                 if (tz->governor->bind_to_tz(tz)) {
  86                         dev_err(&tz->device,
  87                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  88                                 failed_gov_name, tz->governor->name, tz->type);
  89                         tz->governor = NULL;
  90                 }
  91         }
  92 }
  93
  94 /**
  95  * thermal_set_governor() - Switch to another governor
  96  * @tz:         a valid pointer to a struct thermal_zone_device
  97  * @new_gov:    pointer to the new governor
  98  *
  99  * Change the governor of thermal zone @tz.
 100  *
 101  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 102  */
 103 static int thermal_set_governor(struct thermal_zone_device *tz,
 104                                 struct thermal_governor *new_gov)
 105 {
 106         int ret = 0;
 107
 108         if (tz->governor && tz->governor->unbind_from_tz)
 109                 tz->governor->unbind_from_tz(tz);
 110
 111         if (new_gov && new_gov->bind_to_tz) {
 112                 ret = new_gov->bind_to_tz(tz);
 113                 if (ret) {
 114                         bind_previous_governor(tz, new_gov->name);
 115
 116                         return ret;
 117                 }
 118         }
 119
 120         tz->governor = new_gov;
 121
 122         return ret;
 123 }
 124
 125 int thermal_register_governor(struct thermal_governor *governor)
 126 {
 127         int err;
 128         const char *name;
 129         struct thermal_zone_device *pos;
 130
 131         if (!governor)
 132                 return -EINVAL;
 133
 134         mutex_lock(&thermal_governor_lock);
 135
 136         err = -EBUSY;
 137         if (!__find_governor(governor->name)) {
 138                 bool match_default;
 139
 140                 err = 0;
 141                 list_add(&governor->governor_list, &thermal_governor_list);
 142                 match_default = !strncmp(governor->name,
 143                                          DEFAULT_THERMAL_GOVERNOR,
 144                                          THERMAL_NAME_LENGTH);
 145
 146                 if (!def_governor && match_default)
 147                         def_governor = governor;
 148         }
 149
 150         mutex_lock(&thermal_list_lock);
 151
 152         list_for_each_entry(pos, &thermal_tz_list, node) {
 153                 /*
 154                  * only thermal zones with specified tz->tzp->governor_name
 155                  * may run with tz->govenor unset
 156                  */
 157                 if (pos->governor)
 158                         continue;
 159
 160                 name = pos->tzp->governor_name;
 161
 162                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 163                         int ret;
 164
 165                         ret = thermal_set_governor(pos, governor);
 166                         if (ret)
 167                                 dev_err(&pos->device,
 168                                         "Failed to set governor %s for thermal zone %s: %d\n",
 169                                         governor->name, pos->type, ret);
 170                 }
 171         }
 172
 173         mutex_unlock(&thermal_list_lock);
 174         mutex_unlock(&thermal_governor_lock);
 175
 176         return err;
 177 }
 178
 179 void thermal_unregister_governor(struct thermal_governor *governor)
 180 {
 181         struct thermal_zone_device *pos;
 182
 183         if (!governor)
 184                 return;
 185
 186         mutex_lock(&thermal_governor_lock);
 187
 188         if (!__find_governor(governor->name))
 189                 goto exit;
 190
 191         mutex_lock(&thermal_list_lock);
 192
 193         list_for_each_entry(pos, &thermal_tz_list, node) {
 194                 if (!strncasecmp(pos->governor->name, governor->name,
 195                                  THERMAL_NAME_LENGTH))
 196                         thermal_set_governor(pos, NULL);
 197         }
 198
 199         mutex_unlock(&thermal_list_lock);
 200         list_del(&governor->governor_list);
 201 exit:
 202         mutex_unlock(&thermal_governor_lock);
 203 }
 204
 205 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 206                                    char *policy)
 207 {
 208         struct thermal_governor *gov;
 209         int ret = -EINVAL;
 210
 211         mutex_lock(&thermal_governor_lock);
 212         mutex_lock(&tz->lock);
 213
 214         gov = __find_governor(strim(policy));
 215         if (!gov)
 216                 goto exit;
 217
 218         ret = thermal_set_governor(tz, gov);
 219
 220 exit:
 221         mutex_unlock(&tz->lock);
 222         mutex_unlock(&thermal_governor_lock);
 223
 224         return ret;
 225 }
 226
 227 int thermal_build_list_of_policies(char *buf)
 228 {
 229         struct thermal_governor *pos;
 230         ssize_t count = 0;
 231
 232         mutex_lock(&thermal_governor_lock);
 233
 234         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 235                 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
 236                                    pos->name);
 237         }
 238         count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
 239
 240         mutex_unlock(&thermal_governor_lock);
 241
 242         return count;
 243 }
 244
 245 static int __init thermal_register_governors(void)
 246 {
 247         int result;
 248
 249         result = thermal_gov_step_wise_register();
 250         if (result)
 251                 return result;
 252
 253         result = thermal_gov_fair_share_register();
 254         if (result)
 255                 return result;
 256
 257         result = thermal_gov_bang_bang_register();
 258         if (result)
 259                 return result;
 260
 261         result = thermal_gov_user_space_register();
 262         if (result)
 263                 return result;
 264
 265         return thermal_gov_power_allocator_register();
 266 }
 267
 268 static void thermal_unregister_governors(void)
 269 {
 270         thermal_gov_step_wise_unregister();
 271         thermal_gov_fair_share_unregister();
 272         thermal_gov_bang_bang_unregister();
 273         thermal_gov_user_space_unregister();
 274         thermal_gov_power_allocator_unregister();
 275 }
 276
 277 /*
 278  * Zone update section: main control loop applied to each zone while monitoring
 279  *
 280  * in polling mode. The monitoring is done using a workqueue.
 281  * Same update may be done on a zone by calling thermal_zone_device_update().
 282  *
 283  * An update means:
 284  * - Non-critical trips will invoke the governor responsible for that zone;
 285  * - Hot trips will produce a notification to userspace;
 286  * - Critical trip point will cause a system shutdown.
 287  */
 288 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 289                                             int delay)
 290 {
 291         if (delay > 1000)
 292                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 293                                  round_jiffies(msecs_to_jiffies(delay)));
 294         else if (delay)
 295                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 296                                  msecs_to_jiffies(delay));
 297         else
 298                 cancel_delayed_work(&tz->poll_queue);
 299 }
 300
 301 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 302 {
 303         mutex_lock(&tz->lock);
 304
 305         if (tz->passive)
 306                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 307         else if (tz->polling_delay)
 308                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 309         else
 310                 thermal_zone_device_set_polling(tz, 0);
 311
 312         mutex_unlock(&tz->lock);
 313 }
 314
 315 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 316                                       int trip,
 317                                       enum thermal_trip_type trip_type)
 318 {
 319         tz->governor ? tz->governor->throttle(tz, trip) :
 320                        def_governor->throttle(tz, trip);
 321 }
 322
 323 /**
 324  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 325  * @work: work_struct associated with the emergency poweroff function
 326  *
 327  * This function is called in very critical situations to force
 328  * a kernel poweroff after a configurable timeout value.
 329  */
 330 static void thermal_emergency_poweroff_func(struct work_struct *work)
 331 {
 332         /*
 333          * We have reached here after the emergency thermal shutdown
 334          * Waiting period has expired. This means orderly_poweroff has
 335          * not been able to shut off the system for some reason.
 336          * Try to shut down the system immediately using kernel_power_off
 337          * if populated
 338          */
 339         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 340         kernel_power_off();
 341
 342         /*
 343          * Worst of the worst case trigger emergency restart
 344          */
 345         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 346         emergency_restart();
 347 }
 348
 349 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 350                             thermal_emergency_poweroff_func);
 351
 352 /**
 353  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 354  *
 355  * This may be called from any critical situation to trigger a system shutdown
 356  * after a known period of time. By default this is not scheduled.
 357  */
 358 static void thermal_emergency_poweroff(void)
 359 {
 360         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 361         /*
 362          * poweroff_delay_ms must be a carefully profiled positive value.
 363          * Its a must for thermal_emergency_poweroff_work to be scheduled
 364          */
 365         if (poweroff_delay_ms <= 0)
 366                 return;
 367         schedule_delayed_work(&thermal_emergency_poweroff_work,
 368                               msecs_to_jiffies(poweroff_delay_ms));
 369 }
 370
 371 static void handle_critical_trips(struct thermal_zone_device *tz,
 372                                   int trip, enum thermal_trip_type trip_type)
 373 {
 374         int trip_temp;
 375
 376         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 377
 378         /* If we have not crossed the trip_temp, we do not care. */
 379         if (trip_temp <= 0 || tz->temperature < trip_temp)
 380                 return;
 381
 382         trace_thermal_zone_trip(tz, trip, trip_type);
 383
 384         if (tz->ops->notify)
 385                 tz->ops->notify(tz, trip, trip_type);
 386
 387         if (trip_type == THERMAL_TRIP_CRITICAL) {
 388                 dev_emerg(&tz->device,
 389                           "critical temperature reached (%d C), shutting down\n",
 390                           tz->temperature / 1000);
 391                 mutex_lock(&poweroff_lock);
 392                 if (!power_off_triggered) {
 393                         /*
 394                          * Queue a backup emergency shutdown in the event of
 395                          * orderly_poweroff failure
 396                          */
 397                         thermal_emergency_poweroff();
 398                         orderly_poweroff(true);
 399                         power_off_triggered = true;
 400                 }
 401                 mutex_unlock(&poweroff_lock);
 402         }
 403 }
 404
 405 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 406 {
 407         enum thermal_trip_type type;
 408
 409         /* Ignore disabled trip points */
 410         if (test_bit(trip, &tz->trips_disabled))
 411                 return;
 412
 413         tz->ops->get_trip_type(tz, trip, &type);
 414
 415         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 416                 handle_critical_trips(tz, trip, type);
 417         else
 418                 handle_non_critical_trips(tz, trip, type);
 419         /*
 420          * Alright, we handled this trip successfully.
 421          * So, start monitoring again.
 422          */
 423         monitor_thermal_zone(tz);
 424 }
 425
 426 static void update_temperature(struct thermal_zone_device *tz)
 427 {
 428         int temp, ret;
 429
 430         ret = thermal_zone_get_temp(tz, &temp);
 431         if (ret) {
 432                 if (ret != -EAGAIN)
 433                         dev_warn(&tz->device,
 434                                  "failed to read out thermal zone (%d)\n",
 435                                  ret);
 436                 return;
 437         }
 438
 439         mutex_lock(&tz->lock);
 440         tz->last_temperature = tz->temperature;
 441         tz->temperature = temp;
 442         mutex_unlock(&tz->lock);
 443
 444         trace_thermal_temperature(tz);
 445         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 446                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 447                         tz->temperature);
 448         else
 449                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 450                         tz->last_temperature, tz->temperature);
 451 }
 452
 453 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 454 {
 455         struct thermal_instance *pos;
 456         tz->temperature = THERMAL_TEMP_INVALID;
 457         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 458                 pos->initialized = false;
 459 }
 460
 461 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 462 {
 463         tz->passive = 0;
 464         thermal_zone_device_init(tz);
 465 }
 466
 467 void thermal_zone_device_update(struct thermal_zone_device *tz,
 468                                 enum thermal_notify_event event)
 469 {
 470         int count;
 471
 472         if (atomic_read(&in_suspend))
 473                 return;
 474
 475         if (!tz->ops->get_temp)
 476                 return;
 477
 478         update_temperature(tz);
 479
 480         thermal_zone_set_trips(tz);
 481
 482         tz->notify_event = event;
 483
 484         for (count = 0; count < tz->trips; count++)
 485                 handle_thermal_trip(tz, count);
 486 }
 487 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 488
 489 /**
 490  * thermal_notify_framework - Sensor drivers use this API to notify framework
 491  * @tz:         thermal zone device
 492  * @trip:       indicates which trip point has been crossed
 493  *
 494  * This function handles the trip events from sensor drivers. It starts
 495  * throttling the cooling devices according to the policy configured.
 496  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 497  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 498  * The throttling policy is based on the configured platform data; if no
 499  * platform data is provided, this uses the step_wise throttling policy.
 500  */
 501 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 502 {
 503         handle_thermal_trip(tz, trip);
 504 }
 505 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 506
 507 static void thermal_zone_device_check(struct work_struct *work)
 508 {
 509         struct thermal_zone_device *tz = container_of(work, struct
 510                                                       thermal_zone_device,
 511                                                       poll_queue.work);
 512         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 513 }
 514
 515 /*
 516  * Power actor section: interface to power actors to estimate power
 517  *
 518  * Set of functions used to interact to cooling devices that know
 519  * how to estimate their devices power consumption.
 520  */
 521
 522 /**
 523  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 524  * @cdev:       pointer to &thermal_cooling_device
 525  * @tz:         a valid thermal zone device pointer
 526  * @max_power:  pointer in which to store the maximum power
 527  *
 528  * Calculate the maximum power consumption in milliwats that the
 529  * cooling device can currently consume and store it in @max_power.
 530  *
 531  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 532  * power_actor API or -E* on other error.
 533  */
 534 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 535                               struct thermal_zone_device *tz, u32 *max_power)
 536 {
 537         if (!cdev_is_power_actor(cdev))
 538                 return -EINVAL;
 539
 540         return cdev->ops->state2power(cdev, tz, 0, max_power);
 541 }
 542
 543 /**
 544  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 545  * @cdev:       pointer to &thermal_cooling_device
 546  * @tz:         a valid thermal zone device pointer
 547  * @min_power:  pointer in which to store the minimum power
 548  *
 549  * Calculate the minimum power consumption in milliwatts that the
 550  * cooling device can currently consume and store it in @min_power.
 551  *
 552  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 553  * power_actor API or -E* on other error.
 554  */
 555 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 556                               struct thermal_zone_device *tz, u32 *min_power)
 557 {
 558         unsigned long max_state;
 559         int ret;
 560
 561         if (!cdev_is_power_actor(cdev))
 562                 return -EINVAL;
 563
 564         ret = cdev->ops->get_max_state(cdev, &max_state);
 565         if (ret)
 566                 return ret;
 567
 568         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 569 }
 570
 571 /**
 572  * power_actor_set_power() - limit the maximum power a cooling device consumes
 573  * @cdev:       pointer to &thermal_cooling_device
 574  * @instance:   thermal instance to update
 575  * @power:      the power in milliwatts
 576  *
 577  * Set the cooling device to consume at most @power milliwatts. The limit is
 578  * expected to be a cap at the maximum power consumption.
 579  *
 580  * Return: 0 on success, -EINVAL if the cooling device does not
 581  * implement the power actor API or -E* for other failures.
 582  */
 583 int power_actor_set_power(struct thermal_cooling_device *cdev,
 584                           struct thermal_instance *instance, u32 power)
 585 {
 586         unsigned long state;
 587         int ret;
 588
 589         if (!cdev_is_power_actor(cdev))
 590                 return -EINVAL;
 591
 592         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 593         if (ret)
 594                 return ret;
 595
 596         instance->target = state;
 597         mutex_lock(&cdev->lock);
 598         cdev->updated = false;
 599         mutex_unlock(&cdev->lock);
 600         thermal_cdev_update(cdev);
 601
 602         return 0;
 603 }
 604
 605 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 606                                           const char *cdev_type, size_t size)
 607 {
 608         struct thermal_cooling_device *cdev = NULL;
 609
 610         mutex_lock(&thermal_list_lock);
 611         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 612                 /* skip non matching cdevs */
 613                 if (strncmp(cdev_type, cdev->type, size))
 614                         continue;
 615
 616                 /* re binding the exception matching the type pattern */
 617                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 618                                                  THERMAL_NO_LIMIT,
 619                                                  THERMAL_NO_LIMIT,
 620                                                  THERMAL_WEIGHT_DEFAULT);
 621         }
 622         mutex_unlock(&thermal_list_lock);
 623 }
 624
 625 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 626                                           const char *cdev_type, size_t size)
 627 {
 628         struct thermal_cooling_device *cdev = NULL;
 629
 630         mutex_lock(&thermal_list_lock);
 631         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 632                 /* skip non matching cdevs */
 633                 if (strncmp(cdev_type, cdev->type, size))
 634                         continue;
 635                 /* unbinding the exception matching the type pattern */
 636                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 637                                                    cdev);
 638         }
 639         mutex_unlock(&thermal_list_lock);
 640 }
 641
 642 /*
 643  * Device management section: cooling devices, zones devices, and binding
 644  *
 645  * Set of functions provided by the thermal core for:
 646  * - cooling devices lifecycle: registration, unregistration,
 647  *                              binding, and unbinding.
 648  * - thermal zone devices lifecycle: registration, unregistration,
 649  *                                   binding, and unbinding.
 650  */
 651
 652 /**
 653  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 654  * @tz:         pointer to struct thermal_zone_device
 655  * @trip:       indicates which trip point the cooling devices is
 656  *              associated with in this thermal zone.
 657  * @cdev:       pointer to struct thermal_cooling_device
 658  * @upper:      the Maximum cooling state for this trip point.
 659  *              THERMAL_NO_LIMIT means no upper limit,
 660  *              and the cooling device can be in max_state.
 661  * @lower:      the Minimum cooling state can be used for this trip point.
 662  *              THERMAL_NO_LIMIT means no lower limit,
 663  *              and the cooling device can be in cooling state 0.
 664  * @weight:     The weight of the cooling device to be bound to the
 665  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 666  *              default value
 667  *
 668  * This interface function bind a thermal cooling device to the certain trip
 669  * point of a thermal zone device.
 670  * This function is usually called in the thermal zone device .bind callback.
 671  *
 672  * Return: 0 on success, the proper error value otherwise.
 673  */
 674 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 675                                      int trip,
 676                                      struct thermal_cooling_device *cdev,
 677                                      unsigned long upper, unsigned long lower,
 678                                      unsigned int weight)
 679 {
 680         struct thermal_instance *dev;
 681         struct thermal_instance *pos;
 682         struct thermal_zone_device *pos1;
 683         struct thermal_cooling_device *pos2;
 684         unsigned long max_state;
 685         int result, ret;
 686
 687         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 688                 return -EINVAL;
 689
 690         list_for_each_entry(pos1, &thermal_tz_list, node) {
 691                 if (pos1 == tz)
 692                         break;
 693         }
 694         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 695                 if (pos2 == cdev)
 696                         break;
 697         }
 698
 699         if (tz != pos1 || cdev != pos2)
 700                 return -EINVAL;
 701
 702         ret = cdev->ops->get_max_state(cdev, &max_state);
 703         if (ret)
 704                 return ret;
 705
 706         /* lower default 0, upper default max_state */
 707         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 708         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 709
 710         if (lower > upper || upper > max_state)
 711                 return -EINVAL;
 712
 713         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 714         if (!dev)
 715                 return -ENOMEM;
 716         dev->tz = tz;
 717         dev->cdev = cdev;
 718         dev->trip = trip;
 719         dev->upper = upper;
 720         dev->lower = lower;
 721         dev->target = THERMAL_NO_TARGET;
 722         dev->weight = weight;
 723
 724         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 725         if (result < 0)
 726                 goto free_mem;
 727
 728         dev->id = result;
 729         sprintf(dev->name, "cdev%d", dev->id);
 730         result =
 731             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 732         if (result)
 733                 goto release_ida;
 734
 735         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 736         sysfs_attr_init(&dev->attr.attr);
 737         dev->attr.attr.name = dev->attr_name;
 738         dev->attr.attr.mode = 0444;
 739         dev->attr.show = trip_point_show;
 740         result = device_create_file(&tz->device, &dev->attr);
 741         if (result)
 742                 goto remove_symbol_link;
 743
 744         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 745         sysfs_attr_init(&dev->weight_attr.attr);
 746         dev->weight_attr.attr.name = dev->weight_attr_name;
 747         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 748         dev->weight_attr.show = weight_show;
 749         dev->weight_attr.store = weight_store;
 750         result = device_create_file(&tz->device, &dev->weight_attr);
 751         if (result)
 752                 goto remove_trip_file;
 753
 754         mutex_lock(&tz->lock);
 755         mutex_lock(&cdev->lock);
 756         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 757                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 758                         result = -EEXIST;
 759                         break;
 760                 }
 761         if (!result) {
 762                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 763                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 764                 atomic_set(&tz->need_update, 1);
 765         }
 766         mutex_unlock(&cdev->lock);
 767         mutex_unlock(&tz->lock);
 768
 769         if (!result)
 770                 return 0;
 771
 772         device_remove_file(&tz->device, &dev->weight_attr);
 773 remove_trip_file:
 774         device_remove_file(&tz->device, &dev->attr);
 775 remove_symbol_link:
 776         sysfs_remove_link(&tz->device.kobj, dev->name);
 777 release_ida:
 778         ida_simple_remove(&tz->ida, dev->id);
 779 free_mem:
 780         kfree(dev);
 781         return result;
 782 }
 783 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 784
 785 /**
 786  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 787  *                                        thermal zone.
 788  * @tz:         pointer to a struct thermal_zone_device.
 789  * @trip:       indicates which trip point the cooling devices is
 790  *              associated with in this thermal zone.
 791  * @cdev:       pointer to a struct thermal_cooling_device.
 792  *
 793  * This interface function unbind a thermal cooling device from the certain
 794  * trip point of a thermal zone device.
 795  * This function is usually called in the thermal zone device .unbind callback.
 796  *
 797  * Return: 0 on success, the proper error value otherwise.
 798  */
 799 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 800                                        int trip,
 801                                        struct thermal_cooling_device *cdev)
 802 {
 803         struct thermal_instance *pos, *next;
 804
 805         mutex_lock(&tz->lock);
 806         mutex_lock(&cdev->lock);
 807         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 808                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 809                         list_del(&pos->tz_node);
 810                         list_del(&pos->cdev_node);
 811                         mutex_unlock(&cdev->lock);
 812                         mutex_unlock(&tz->lock);
 813                         goto unbind;
 814                 }
 815         }
 816         mutex_unlock(&cdev->lock);
 817         mutex_unlock(&tz->lock);
 818
 819         return -ENODEV;
 820
 821 unbind:
 822         device_remove_file(&tz->device, &pos->weight_attr);
 823         device_remove_file(&tz->device, &pos->attr);
 824         sysfs_remove_link(&tz->device.kobj, pos->name);
 825         ida_simple_remove(&tz->ida, pos->id);
 826         kfree(pos);
 827         return 0;
 828 }
 829 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 830
 831 static void thermal_release(struct device *dev)
 832 {
 833         struct thermal_zone_device *tz;
 834         struct thermal_cooling_device *cdev;
 835
 836         if (!strncmp(dev_name(dev), "thermal_zone",
 837                      sizeof("thermal_zone") - 1)) {
 838                 tz = to_thermal_zone(dev);
 839                 thermal_zone_destroy_device_groups(tz);
 840                 kfree(tz);
 841         } else if (!strncmp(dev_name(dev), "cooling_device",
 842                             sizeof("cooling_device") - 1)) {
 843                 cdev = to_cooling_device(dev);
 844                 kfree(cdev);
 845         }
 846 }
 847
 848 static struct class thermal_class = {
 849         .name = "thermal",
 850         .dev_release = thermal_release,
 851 };
 852
 853 static inline
 854 void print_bind_err_msg(struct thermal_zone_device *tz,
 855                         struct thermal_cooling_device *cdev, int ret)
 856 {
 857         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 858                 tz->type, cdev->type, ret);
 859 }
 860
 861 static void __bind(struct thermal_zone_device *tz, int mask,
 862                    struct thermal_cooling_device *cdev,
 863                    unsigned long *limits,
 864                    unsigned int weight)
 865 {
 866         int i, ret;
 867
 868         for (i = 0; i < tz->trips; i++) {
 869                 if (mask & (1 << i)) {
 870                         unsigned long upper, lower;
 871
 872                         upper = THERMAL_NO_LIMIT;
 873                         lower = THERMAL_NO_LIMIT;
 874                         if (limits) {
 875                                 lower = limits[i * 2];
 876                                 upper = limits[i * 2 + 1];
 877                         }
 878                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 879                                                                upper, lower,
 880                                                                weight);
 881                         if (ret)
 882                                 print_bind_err_msg(tz, cdev, ret);
 883                 }
 884         }
 885 }
 886
 887 static void bind_cdev(struct thermal_cooling_device *cdev)
 888 {
 889         int i, ret;
 890         const struct thermal_zone_params *tzp;
 891         struct thermal_zone_device *pos = NULL;
 892
 893         mutex_lock(&thermal_list_lock);
 894
 895         list_for_each_entry(pos, &thermal_tz_list, node) {
 896                 if (!pos->tzp && !pos->ops->bind)
 897                         continue;
 898
 899                 if (pos->ops->bind) {
 900                         ret = pos->ops->bind(pos, cdev);
 901                         if (ret)
 902                                 print_bind_err_msg(pos, cdev, ret);
 903                         continue;
 904                 }
 905
 906                 tzp = pos->tzp;
 907                 if (!tzp || !tzp->tbp)
 908                         continue;
 909
 910                 for (i = 0; i < tzp->num_tbps; i++) {
 911                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 912                                 continue;
 913                         if (tzp->tbp[i].match(pos, cdev))
 914                                 continue;
 915                         tzp->tbp[i].cdev = cdev;
 916                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 917                                tzp->tbp[i].binding_limits,
 918                                tzp->tbp[i].weight);
 919                 }
 920         }
 921
 922         mutex_unlock(&thermal_list_lock);
 923 }
 924
 925 /**
 926  * __thermal_cooling_device_register() - register a new thermal cooling device
 927  * @np:         a pointer to a device tree node.
 928  * @type:       the thermal cooling device type.
 929  * @devdata:    device private data.
 930  * @ops:                standard thermal cooling devices callbacks.
 931  *
 932  * This interface function adds a new thermal cooling device (fan/processor/...)
 933  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 934  * to all the thermal zone devices registered at the same time.
 935  * It also gives the opportunity to link the cooling device to a device tree
 936  * node, so that it can be bound to a thermal zone created out of device tree.
 937  *
 938  * Return: a pointer to the created struct thermal_cooling_device or an
 939  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 940  */
 941 static struct thermal_cooling_device *
 942 __thermal_cooling_device_register(struct device_node *np,
 943                                   char *type, void *devdata,
 944                                   const struct thermal_cooling_device_ops *ops)
 945 {
 946         struct thermal_cooling_device *cdev;
 947         struct thermal_zone_device *pos = NULL;
 948         int result;
 949
 950         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 951                 return ERR_PTR(-EINVAL);
 952
 953         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 954             !ops->set_cur_state)
 955                 return ERR_PTR(-EINVAL);
 956
 957         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 958         if (!cdev)
 959                 return ERR_PTR(-ENOMEM);
 960
 961         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 962         if (result < 0) {
 963                 kfree(cdev);
 964                 return ERR_PTR(result);
 965         }
 966
 967         cdev->id = result;
 968         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 969         mutex_init(&cdev->lock);
 970         INIT_LIST_HEAD(&cdev->thermal_instances);
 971         cdev->np = np;
 972         cdev->ops = ops;
 973         cdev->updated = false;
 974         cdev->device.class = &thermal_class;
 975         cdev->devdata = devdata;
 976         thermal_cooling_device_setup_sysfs(cdev);
 977         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 978         result = device_register(&cdev->device);
 979         if (result) {
 980                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 981                 kfree(cdev);
 982                 return ERR_PTR(result);
 983         }
 984
 985         /* Add 'this' new cdev to the global cdev list */
 986         mutex_lock(&thermal_list_lock);
 987         list_add(&cdev->node, &thermal_cdev_list);
 988         mutex_unlock(&thermal_list_lock);
 989
 990         /* Update binding information for 'this' new cdev */
 991         bind_cdev(cdev);
 992
 993         mutex_lock(&thermal_list_lock);
 994         list_for_each_entry(pos, &thermal_tz_list, node)
 995                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 996                         thermal_zone_device_update(pos,
 997                                                    THERMAL_EVENT_UNSPECIFIED);
 998         mutex_unlock(&thermal_list_lock);
 999
1000         return cdev;
1001 }
1002
1003 /**
1004  * thermal_cooling_device_register() - register a new thermal cooling device
1005  * @type:       the thermal cooling device type.
1006  * @devdata:    device private data.
1007  * @ops:                standard thermal cooling devices callbacks.
1008  *
1009  * This interface function adds a new thermal cooling device (fan/processor/...)
1010  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1011  * to all the thermal zone devices registered at the same time.
1012  *
1013  * Return: a pointer to the created struct thermal_cooling_device or an
1014  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1015  */
1016 struct thermal_cooling_device *
1017 thermal_cooling_device_register(char *type, void *devdata,
1018                                 const struct thermal_cooling_device_ops *ops)
1019 {
1020         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1021 }
1022 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1023
1024 /**
1025  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1026  * @np:         a pointer to a device tree node.
1027  * @type:       the thermal cooling device type.
1028  * @devdata:    device private data.
1029  * @ops:                standard thermal cooling devices callbacks.
1030  *
1031  * This function will register a cooling device with device tree node reference.
1032  * This interface function adds a new thermal cooling device (fan/processor/...)
1033  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1034  * to all the thermal zone devices registered at the same time.
1035  *
1036  * Return: a pointer to the created struct thermal_cooling_device or an
1037  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1038  */
1039 struct thermal_cooling_device *
1040 thermal_of_cooling_device_register(struct device_node *np,
1041                                    char *type, void *devdata,
1042                                    const struct thermal_cooling_device_ops *ops)
1043 {
1044         return __thermal_cooling_device_register(np, type, devdata, ops);
1045 }
1046 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1047
1048 static void __unbind(struct thermal_zone_device *tz, int mask,
1049                      struct thermal_cooling_device *cdev)
1050 {
1051         int i;
1052
1053         for (i = 0; i < tz->trips; i++)
1054                 if (mask & (1 << i))
1055                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1056 }
1057
1058 /**
1059  * thermal_cooling_device_unregister - removes a thermal cooling device
1060  * @cdev:       the thermal cooling device to remove.
1061  *
1062  * thermal_cooling_device_unregister() must be called when a registered
1063  * thermal cooling device is no longer needed.
1064  */
1065 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1066 {
1067         int i;
1068         const struct thermal_zone_params *tzp;
1069         struct thermal_zone_device *tz;
1070         struct thermal_cooling_device *pos = NULL;
1071
1072         if (!cdev)
1073                 return;
1074
1075         mutex_lock(&thermal_list_lock);
1076         list_for_each_entry(pos, &thermal_cdev_list, node)
1077                 if (pos == cdev)
1078                         break;
1079         if (pos != cdev) {
1080                 /* thermal cooling device not found */
1081                 mutex_unlock(&thermal_list_lock);
1082                 return;
1083         }
1084         list_del(&cdev->node);
1085
1086         /* Unbind all thermal zones associated with 'this' cdev */
1087         list_for_each_entry(tz, &thermal_tz_list, node) {
1088                 if (tz->ops->unbind) {
1089                         tz->ops->unbind(tz, cdev);
1090                         continue;
1091                 }
1092
1093                 if (!tz->tzp || !tz->tzp->tbp)
1094                         continue;
1095
1096                 tzp = tz->tzp;
1097                 for (i = 0; i < tzp->num_tbps; i++) {
1098                         if (tzp->tbp[i].cdev == cdev) {
1099                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1100                                 tzp->tbp[i].cdev = NULL;
1101                         }
1102                 }
1103         }
1104
1105         mutex_unlock(&thermal_list_lock);
1106
1107         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1108         device_del(&cdev->device);
1109         thermal_cooling_device_destroy_sysfs(cdev);
1110         put_device(&cdev->device);
1111 }
1112 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1113
1114 static void bind_tz(struct thermal_zone_device *tz)
1115 {
1116         int i, ret;
1117         struct thermal_cooling_device *pos = NULL;
1118         const struct thermal_zone_params *tzp = tz->tzp;
1119
1120         if (!tzp && !tz->ops->bind)
1121                 return;
1122
1123         mutex_lock(&thermal_list_lock);
1124
1125         /* If there is ops->bind, try to use ops->bind */
1126         if (tz->ops->bind) {
1127                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1128                         ret = tz->ops->bind(tz, pos);
1129                         if (ret)
1130                                 print_bind_err_msg(tz, pos, ret);
1131                 }
1132                 goto exit;
1133         }
1134
1135         if (!tzp || !tzp->tbp)
1136                 goto exit;
1137
1138         list_for_each_entry(pos, &thermal_cdev_list, node) {
1139                 for (i = 0; i < tzp->num_tbps; i++) {
1140                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1141                                 continue;
1142                         if (tzp->tbp[i].match(tz, pos))
1143                                 continue;
1144                         tzp->tbp[i].cdev = pos;
1145                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1146                                tzp->tbp[i].binding_limits,
1147                                tzp->tbp[i].weight);
1148                 }
1149         }
1150 exit:
1151         mutex_unlock(&thermal_list_lock);
1152 }
1153
1154 /**
1155  * thermal_zone_device_register() - register a new thermal zone device
1156  * @type:       the thermal zone device type
1157  * @trips:      the number of trip points the thermal zone support
1158  * @mask:       a bit string indicating the writeablility of trip points
1159  * @devdata:    private device data
1160  * @ops:        standard thermal zone device callbacks
1161  * @tzp:        thermal zone platform parameters
1162  * @passive_delay: number of milliseconds to wait between polls when
1163  *                 performing passive cooling
1164  * @polling_delay: number of milliseconds to wait between polls when checking
1165  *                 whether trip points have been crossed (0 for interrupt
1166  *                 driven systems)
1167  *
1168  * This interface function adds a new thermal zone device (sensor) to
1169  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1170  * thermal cooling devices registered at the same time.
1171  * thermal_zone_device_unregister() must be called when the device is no
1172  * longer needed. The passive cooling depends on the .get_trend() return value.
1173  *
1174  * Return: a pointer to the created struct thermal_zone_device or an
1175  * in case of error, an ERR_PTR. Caller must check return value with
1176  * IS_ERR*() helpers.
1177  */
1178 struct thermal_zone_device *
1179 thermal_zone_device_register(const char *type, int trips, int mask,
1180                              void *devdata, struct thermal_zone_device_ops *ops,
1181                              struct thermal_zone_params *tzp, int passive_delay,
1182                              int polling_delay)
1183 {
1184         struct thermal_zone_device *tz;
1185         enum thermal_trip_type trip_type;
1186         int trip_temp;
1187         int result;
1188         int count;
1189         struct thermal_governor *governor;
1190
1191         if (!type || strlen(type) == 0)
1192                 return ERR_PTR(-EINVAL);
1193
1194         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1195                 return ERR_PTR(-EINVAL);
1196
1197         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1198                 return ERR_PTR(-EINVAL);
1199
1200         if (!ops)
1201                 return ERR_PTR(-EINVAL);
1202
1203         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1204                 return ERR_PTR(-EINVAL);
1205
1206         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1207         if (!tz)
1208                 return ERR_PTR(-ENOMEM);
1209
1210         INIT_LIST_HEAD(&tz->thermal_instances);
1211         ida_init(&tz->ida);
1212         mutex_init(&tz->lock);
1213         result = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1214         if (result < 0)
1215                 goto free_tz;
1216
1217         tz->id = result;
1218         strlcpy(tz->type, type, sizeof(tz->type));
1219         tz->ops = ops;
1220         tz->tzp = tzp;
1221         tz->device.class = &thermal_class;
1222         tz->devdata = devdata;
1223         tz->trips = trips;
1224         tz->passive_delay = passive_delay;
1225         tz->polling_delay = polling_delay;
1226
1227         /* sys I/F */
1228         /* Add nodes that are always present via .groups */
1229         result = thermal_zone_create_device_groups(tz, mask);
1230         if (result)
1231                 goto remove_id;
1232
1233         /* A new thermal zone needs to be updated anyway. */
1234         atomic_set(&tz->need_update, 1);
1235
1236         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1237         result = device_register(&tz->device);
1238         if (result)
1239                 goto remove_device_groups;
1240
1241         for (count = 0; count < trips; count++) {
1242                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1243                         set_bit(count, &tz->trips_disabled);
1244                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1245                         set_bit(count, &tz->trips_disabled);
1246                 /* Check for bogus trip points */
1247                 if (trip_temp == 0)
1248                         set_bit(count, &tz->trips_disabled);
1249         }
1250
1251         /* Update 'this' zone's governor information */
1252         mutex_lock(&thermal_governor_lock);
1253
1254         if (tz->tzp)
1255                 governor = __find_governor(tz->tzp->governor_name);
1256         else
1257                 governor = def_governor;
1258
1259         result = thermal_set_governor(tz, governor);
1260         if (result) {
1261                 mutex_unlock(&thermal_governor_lock);
1262                 goto unregister;
1263         }
1264
1265         mutex_unlock(&thermal_governor_lock);
1266
1267         if (!tz->tzp || !tz->tzp->no_hwmon) {
1268                 result = thermal_add_hwmon_sysfs(tz);
1269                 if (result)
1270                         goto unregister;
1271         }
1272
1273         mutex_lock(&thermal_list_lock);
1274         list_add_tail(&tz->node, &thermal_tz_list);
1275         mutex_unlock(&thermal_list_lock);
1276
1277         /* Bind cooling devices for this zone */
1278         bind_tz(tz);
1279
1280         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1281
1282         thermal_zone_device_reset(tz);
1283         /* Update the new thermal zone and mark it as already updated. */
1284         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1285                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1286
1287         return tz;
1288
1289 unregister:
1290         ida_simple_remove(&thermal_tz_ida, tz->id);
1291         device_unregister(&tz->device);
1292         return ERR_PTR(result);
1293
1294 remove_device_groups:
1295         thermal_zone_destroy_device_groups(tz);
1296 remove_id:
1297         ida_simple_remove(&thermal_tz_ida, tz->id);
1298 free_tz:
1299         kfree(tz);
1300         return ERR_PTR(result);
1301 }
1302 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1303
1304 /**
1305  * thermal_zone_device_unregister - removes the registered thermal zone device
1306  * @tz: the thermal zone device to remove
1307  */
1308 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1309 {
1310         int i;
1311         const struct thermal_zone_params *tzp;
1312         struct thermal_cooling_device *cdev;
1313         struct thermal_zone_device *pos = NULL;
1314
1315         if (!tz)
1316                 return;
1317
1318         tzp = tz->tzp;
1319
1320         mutex_lock(&thermal_list_lock);
1321         list_for_each_entry(pos, &thermal_tz_list, node)
1322                 if (pos == tz)
1323                         break;
1324         if (pos != tz) {
1325                 /* thermal zone device not found */
1326                 mutex_unlock(&thermal_list_lock);
1327                 return;
1328         }
1329         list_del(&tz->node);
1330
1331         /* Unbind all cdevs associated with 'this' thermal zone */
1332         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1333                 if (tz->ops->unbind) {
1334                         tz->ops->unbind(tz, cdev);
1335                         continue;
1336                 }
1337
1338                 if (!tzp || !tzp->tbp)
1339                         break;
1340
1341                 for (i = 0; i < tzp->num_tbps; i++) {
1342                         if (tzp->tbp[i].cdev == cdev) {
1343                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1344                                 tzp->tbp[i].cdev = NULL;
1345                         }
1346                 }
1347         }
1348
1349         mutex_unlock(&thermal_list_lock);
1350
1351         cancel_delayed_work_sync(&tz->poll_queue);
1352
1353         thermal_set_governor(tz, NULL);
1354
1355         thermal_remove_hwmon_sysfs(tz);
1356         ida_simple_remove(&thermal_tz_ida, tz->id);
1357         ida_destroy(&tz->ida);
1358         mutex_destroy(&tz->lock);
1359         device_unregister(&tz->device);
1360 }
1361 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1362
1363 /**
1364  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1365  * @name: thermal zone name to fetch the temperature
1366  *
1367  * When only one zone is found with the passed name, returns a reference to it.
1368  *
1369  * Return: On success returns a reference to an unique thermal zone with
1370  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1371  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1372  */
1373 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1374 {
1375         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1376         unsigned int found = 0;
1377
1378         if (!name)
1379                 goto exit;
1380
1381         mutex_lock(&thermal_list_lock);
1382         list_for_each_entry(pos, &thermal_tz_list, node)
1383                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1384                         found++;
1385                         ref = pos;
1386                 }
1387         mutex_unlock(&thermal_list_lock);
1388
1389         /* nothing has been found, thus an error code for it */
1390         if (found == 0)
1391                 ref = ERR_PTR(-ENODEV);
1392         else if (found > 1)
1393         /* Success only when an unique zone is found */
1394                 ref = ERR_PTR(-EEXIST);
1395
1396 exit:
1397         return ref;
1398 }
1399 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1400
1401 #ifdef CONFIG_NET
1402 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1403         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1404 };
1405
1406 static struct genl_family thermal_event_genl_family __ro_after_init = {
1407         .module = THIS_MODULE,
1408         .name = THERMAL_GENL_FAMILY_NAME,
1409         .version = THERMAL_GENL_VERSION,
1410         .maxattr = THERMAL_GENL_ATTR_MAX,
1411         .mcgrps = thermal_event_mcgrps,
1412         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1413 };
1414
1415 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1416                                    enum events event)
1417 {
1418         struct sk_buff *skb;
1419         struct nlattr *attr;
1420         struct thermal_genl_event *thermal_event;
1421         void *msg_header;
1422         int size;
1423         int result;
1424         static unsigned int thermal_event_seqnum;
1425
1426         if (!tz)
1427                 return -EINVAL;
1428
1429         /* allocate memory */
1430         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1431                nla_total_size(0);
1432
1433         skb = genlmsg_new(size, GFP_ATOMIC);
1434         if (!skb)
1435                 return -ENOMEM;
1436
1437         /* add the genetlink message header */
1438         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1439                                  &thermal_event_genl_family, 0,
1440                                  THERMAL_GENL_CMD_EVENT);
1441         if (!msg_header) {
1442                 nlmsg_free(skb);
1443                 return -ENOMEM;
1444         }
1445
1446         /* fill the data */
1447         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1448                            sizeof(struct thermal_genl_event));
1449
1450         if (!attr) {
1451                 nlmsg_free(skb);
1452                 return -EINVAL;
1453         }
1454
1455         thermal_event = nla_data(attr);
1456         if (!thermal_event) {
1457                 nlmsg_free(skb);
1458                 return -EINVAL;
1459         }
1460
1461         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1462
1463         thermal_event->orig = tz->id;
1464         thermal_event->event = event;
1465
1466         /* send multicast genetlink message */
1467         genlmsg_end(skb, msg_header);
1468
1469         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1470                                    0, GFP_ATOMIC);
1471         if (result)
1472                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1473
1474         return result;
1475 }
1476 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1477
1478 static int __init genetlink_init(void)
1479 {
1480         return genl_register_family(&thermal_event_genl_family);
1481 }
1482
1483 static void genetlink_exit(void)
1484 {
1485         genl_unregister_family(&thermal_event_genl_family);
1486 }
1487 #else /* !CONFIG_NET */
1488 static inline int genetlink_init(void) { return 0; }
1489 static inline void genetlink_exit(void) {}
1490 #endif /* !CONFIG_NET */
1491
1492 static int thermal_pm_notify(struct notifier_block *nb,
1493                              unsigned long mode, void *_unused)
1494 {
1495         struct thermal_zone_device *tz;
1496
1497         switch (mode) {
1498         case PM_HIBERNATION_PREPARE:
1499         case PM_RESTORE_PREPARE:
1500         case PM_SUSPEND_PREPARE:
1501                 atomic_set(&in_suspend, 1);
1502                 break;
1503         case PM_POST_HIBERNATION:
1504         case PM_POST_RESTORE:
1505         case PM_POST_SUSPEND:
1506                 atomic_set(&in_suspend, 0);
1507                 list_for_each_entry(tz, &thermal_tz_list, node) {
1508                         thermal_zone_device_init(tz);
1509                         thermal_zone_device_update(tz,
1510                                                    THERMAL_EVENT_UNSPECIFIED);
1511                 }
1512                 break;
1513         default:
1514                 break;
1515         }
1516         return 0;
1517 }
1518
1519 static struct notifier_block thermal_pm_nb = {
1520         .notifier_call = thermal_pm_notify,
1521 };
1522
1523 static int __init thermal_init(void)
1524 {
1525         int result;
1526
1527         mutex_init(&poweroff_lock);
1528         result = thermal_register_governors();
1529         if (result)
1530                 goto error;
1531
1532         result = class_register(&thermal_class);
1533         if (result)
1534                 goto unregister_governors;
1535
1536         result = genetlink_init();
1537         if (result)
1538                 goto unregister_class;
1539
1540         result = of_parse_thermal_zones();
1541         if (result)
1542                 goto exit_netlink;
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 exit_netlink:
1552         genetlink_exit();
1553 unregister_class:
1554         class_unregister(&thermal_class);
1555 unregister_governors:
1556         thermal_unregister_governors();
1557 error:
1558         ida_destroy(&thermal_tz_ida);
1559         ida_destroy(&thermal_cdev_ida);
1560         mutex_destroy(&thermal_list_lock);
1561         mutex_destroy(&thermal_governor_lock);
1562         mutex_destroy(&poweroff_lock);
1563         return result;
1564 }
1565
1566 static void __exit thermal_exit(void)
1567 {
1568         unregister_pm_notifier(&thermal_pm_nb);
1569         of_thermal_destroy_zones();
1570         genetlink_exit();
1571         class_unregister(&thermal_class);
1572         thermal_unregister_governors();
1573         ida_destroy(&thermal_tz_ida);
1574         ida_destroy(&thermal_cdev_ida);
1575         mutex_destroy(&thermal_list_lock);
1576         mutex_destroy(&thermal_governor_lock);
1577 }
1578
1579 fs_initcall(thermal_init);
1580 module_exit(thermal_exit);