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