linux/drivers/thermal/thermal_core.c
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   1/*
   2 *  thermal.c - Generic Thermal Management Sysfs support.
   3 *
   4 *  Copyright (C) 2008 Intel Corp
   5 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   6 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   7 *
   8 *  This program is free software; you can redistribute it and/or modify
   9 *  it under the terms of the GNU General Public License as published by
  10 *  the Free Software Foundation; version 2 of the License.
  11 */
  12
  13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15#include <linux/module.h>
  16#include <linux/device.h>
  17#include <linux/err.h>
  18#include <linux/slab.h>
  19#include <linux/kdev_t.h>
  20#include <linux/idr.h>
  21#include <linux/thermal.h>
  22#include <linux/reboot.h>
  23#include <linux/string.h>
  24#include <linux/of.h>
  25#include <net/netlink.h>
  26#include <net/genetlink.h>
  27#include <linux/suspend.h>
  28
  29#define CREATE_TRACE_POINTS
  30#include <trace/events/thermal.h>
  31
  32#include "thermal_core.h"
  33#include "thermal_hwmon.h"
  34
  35MODULE_AUTHOR("Zhang Rui");
  36MODULE_DESCRIPTION("Generic thermal management sysfs support");
  37MODULE_LICENSE("GPL v2");
  38
  39static DEFINE_IDA(thermal_tz_ida);
  40static DEFINE_IDA(thermal_cdev_ida);
  41
  42static LIST_HEAD(thermal_tz_list);
  43static LIST_HEAD(thermal_cdev_list);
  44static LIST_HEAD(thermal_governor_list);
  45
  46static DEFINE_MUTEX(thermal_list_lock);
  47static DEFINE_MUTEX(thermal_governor_lock);
  48static DEFINE_MUTEX(poweroff_lock);
  49
  50static atomic_t in_suspend;
  51static bool power_off_triggered;
  52
  53static struct thermal_governor *def_governor;
  54
  55/*
  56 * Governor section: set of functions to handle thermal governors
  57 *
  58 * Functions to help in the life cycle of thermal governors within
  59 * the thermal core and by the thermal governor code.
  60 */
  61
  62static struct thermal_governor *__find_governor(const char *name)
  63{
  64        struct thermal_governor *pos;
  65
  66        if (!name || !name[0])
  67                return def_governor;
  68
  69        list_for_each_entry(pos, &thermal_governor_list, governor_list)
  70                if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  71                        return pos;
  72
  73        return NULL;
  74}
  75
  76/**
  77 * bind_previous_governor() - bind the previous governor of the thermal zone
  78 * @tz:         a valid pointer to a struct thermal_zone_device
  79 * @failed_gov_name:    the name of the governor that failed to register
  80 *
  81 * Register the previous governor of the thermal zone after a new
  82 * governor has failed to be bound.
  83 */
  84static void bind_previous_governor(struct thermal_zone_device *tz,
  85                                   const char *failed_gov_name)
  86{
  87        if (tz->governor && tz->governor->bind_to_tz) {
  88                if (tz->governor->bind_to_tz(tz)) {
  89                        dev_err(&tz->device,
  90                                "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  91                                failed_gov_name, tz->governor->name, tz->type);
  92                        tz->governor = NULL;
  93                }
  94        }
  95}
  96
  97/**
  98 * thermal_set_governor() - Switch to another governor
  99 * @tz:         a valid pointer to a struct thermal_zone_device
 100 * @new_gov:    pointer to the new governor
 101 *
 102 * Change the governor of thermal zone @tz.
 103 *
 104 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 105 */
 106static int thermal_set_governor(struct thermal_zone_device *tz,
 107                                struct thermal_governor *new_gov)
 108{
 109        int ret = 0;
 110
 111        if (tz->governor && tz->governor->unbind_from_tz)
 112                tz->governor->unbind_from_tz(tz);
 113
 114        if (new_gov && new_gov->bind_to_tz) {
 115                ret = new_gov->bind_to_tz(tz);
 116                if (ret) {
 117                        bind_previous_governor(tz, new_gov->name);
 118
 119                        return ret;
 120                }
 121        }
 122
 123        tz->governor = new_gov;
 124
 125        return ret;
 126}
 127
 128int thermal_register_governor(struct thermal_governor *governor)
 129{
 130        int err;
 131        const char *name;
 132        struct thermal_zone_device *pos;
 133
 134        if (!governor)
 135                return -EINVAL;
 136
 137        mutex_lock(&thermal_governor_lock);
 138
 139        err = -EBUSY;
 140        if (!__find_governor(governor->name)) {
 141                bool match_default;
 142
 143                err = 0;
 144                list_add(&governor->governor_list, &thermal_governor_list);
 145                match_default = !strncmp(governor->name,
 146                                         DEFAULT_THERMAL_GOVERNOR,
 147                                         THERMAL_NAME_LENGTH);
 148
 149                if (!def_governor && match_default)
 150                        def_governor = governor;
 151        }
 152
 153        mutex_lock(&thermal_list_lock);
 154
 155        list_for_each_entry(pos, &thermal_tz_list, node) {
 156                /*
 157                 * only thermal zones with specified tz->tzp->governor_name
 158                 * may run with tz->govenor unset
 159                 */
 160                if (pos->governor)
 161                        continue;
 162
 163                name = pos->tzp->governor_name;
 164
 165                if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 166                        int ret;
 167
 168                        ret = thermal_set_governor(pos, governor);
 169                        if (ret)
 170                                dev_err(&pos->device,
 171                                        "Failed to set governor %s for thermal zone %s: %d\n",
 172                                        governor->name, pos->type, ret);
 173                }
 174        }
 175
 176        mutex_unlock(&thermal_list_lock);
 177        mutex_unlock(&thermal_governor_lock);
 178
 179        return err;
 180}
 181
 182void thermal_unregister_governor(struct thermal_governor *governor)
 183{
 184        struct thermal_zone_device *pos;
 185
 186        if (!governor)
 187                return;
 188
 189        mutex_lock(&thermal_governor_lock);
 190
 191        if (!__find_governor(governor->name))
 192                goto exit;
 193
 194        mutex_lock(&thermal_list_lock);
 195
 196        list_for_each_entry(pos, &thermal_tz_list, node) {
 197                if (!strncasecmp(pos->governor->name, governor->name,
 198                                 THERMAL_NAME_LENGTH))
 199                        thermal_set_governor(pos, NULL);
 200        }
 201
 202        mutex_unlock(&thermal_list_lock);
 203        list_del(&governor->governor_list);
 204exit:
 205        mutex_unlock(&thermal_governor_lock);
 206}
 207
 208int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 209                                   char *policy)
 210{
 211        struct thermal_governor *gov;
 212        int ret = -EINVAL;
 213
 214        mutex_lock(&thermal_governor_lock);
 215        mutex_lock(&tz->lock);
 216
 217        gov = __find_governor(strim(policy));
 218        if (!gov)
 219                goto exit;
 220
 221        ret = thermal_set_governor(tz, gov);
 222
 223exit:
 224        mutex_unlock(&tz->lock);
 225        mutex_unlock(&thermal_governor_lock);
 226
 227        return ret;
 228}
 229
 230int thermal_build_list_of_policies(char *buf)
 231{
 232        struct thermal_governor *pos;
 233        ssize_t count = 0;
 234        ssize_t size = PAGE_SIZE;
 235
 236        mutex_lock(&thermal_governor_lock);
 237
 238        list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 239                size = PAGE_SIZE - count;
 240                count += scnprintf(buf + count, size, "%s ", pos->name);
 241        }
 242        count += scnprintf(buf + count, size, "\n");
 243
 244        mutex_unlock(&thermal_governor_lock);
 245
 246        return count;
 247}
 248
 249static int __init thermal_register_governors(void)
 250{
 251        int result;
 252
 253        result = thermal_gov_step_wise_register();
 254        if (result)
 255                return result;
 256
 257        result = thermal_gov_fair_share_register();
 258        if (result)
 259                return result;
 260
 261        result = thermal_gov_bang_bang_register();
 262        if (result)
 263                return result;
 264
 265        result = thermal_gov_user_space_register();
 266        if (result)
 267                return result;
 268
 269        return thermal_gov_power_allocator_register();
 270}
 271
 272static void thermal_unregister_governors(void)
 273{
 274        thermal_gov_step_wise_unregister();
 275        thermal_gov_fair_share_unregister();
 276        thermal_gov_bang_bang_unregister();
 277        thermal_gov_user_space_unregister();
 278        thermal_gov_power_allocator_unregister();
 279}
 280
 281/*
 282 * Zone update section: main control loop applied to each zone while monitoring
 283 *
 284 * in polling mode. The monitoring is done using a workqueue.
 285 * Same update may be done on a zone by calling thermal_zone_device_update().
 286 *
 287 * An update means:
 288 * - Non-critical trips will invoke the governor responsible for that zone;
 289 * - Hot trips will produce a notification to userspace;
 290 * - Critical trip point will cause a system shutdown.
 291 */
 292static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 293                                            int delay)
 294{
 295        if (delay > 1000)
 296                mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 297                                 round_jiffies(msecs_to_jiffies(delay)));
 298        else if (delay)
 299                mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 300                                 msecs_to_jiffies(delay));
 301        else
 302                cancel_delayed_work(&tz->poll_queue);
 303}
 304
 305static void monitor_thermal_zone(struct thermal_zone_device *tz)
 306{
 307        mutex_lock(&tz->lock);
 308
 309        if (tz->passive)
 310                thermal_zone_device_set_polling(tz, tz->passive_delay);
 311        else if (tz->polling_delay)
 312                thermal_zone_device_set_polling(tz, tz->polling_delay);
 313        else
 314                thermal_zone_device_set_polling(tz, 0);
 315
 316        mutex_unlock(&tz->lock);
 317}
 318
 319static void handle_non_critical_trips(struct thermal_zone_device *tz,
 320                                      int trip,
 321                                      enum thermal_trip_type trip_type)
 322{
 323        tz->governor ? tz->governor->throttle(tz, trip) :
 324                       def_governor->throttle(tz, trip);
 325}
 326
 327/**
 328 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 329 * @work: work_struct associated with the emergency poweroff function
 330 *
 331 * This function is called in very critical situations to force
 332 * a kernel poweroff after a configurable timeout value.
 333 */
 334static void thermal_emergency_poweroff_func(struct work_struct *work)
 335{
 336        /*
 337         * We have reached here after the emergency thermal shutdown
 338         * Waiting period has expired. This means orderly_poweroff has
 339         * not been able to shut off the system for some reason.
 340         * Try to shut down the system immediately using kernel_power_off
 341         * if populated
 342         */
 343        WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 344        kernel_power_off();
 345
 346        /*
 347         * Worst of the worst case trigger emergency restart
 348         */
 349        WARN(1, "Attempting emergency_restart: Temperature too high\n");
 350        emergency_restart();
 351}
 352
 353static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 354                            thermal_emergency_poweroff_func);
 355
 356/**
 357 * thermal_emergency_poweroff - Trigger an emergency system poweroff
 358 *
 359 * This may be called from any critical situation to trigger a system shutdown
 360 * after a known period of time. By default this is not scheduled.
 361 */
 362static void thermal_emergency_poweroff(void)
 363{
 364        int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 365        /*
 366         * poweroff_delay_ms must be a carefully profiled positive value.
 367         * Its a must for thermal_emergency_poweroff_work to be scheduled
 368         */
 369        if (poweroff_delay_ms <= 0)
 370                return;
 371        schedule_delayed_work(&thermal_emergency_poweroff_work,
 372                              msecs_to_jiffies(poweroff_delay_ms));
 373}
 374
 375static void handle_critical_trips(struct thermal_zone_device *tz,
 376                                  int trip, enum thermal_trip_type trip_type)
 377{
 378        int trip_temp;
 379
 380        tz->ops->get_trip_temp(tz, trip, &trip_temp);
 381
 382        /* If we have not crossed the trip_temp, we do not care. */
 383        if (trip_temp <= 0 || tz->temperature < trip_temp)
 384                return;
 385
 386        trace_thermal_zone_trip(tz, trip, trip_type);
 387
 388        if (tz->ops->notify)
 389                tz->ops->notify(tz, trip, trip_type);
 390
 391        if (trip_type == THERMAL_TRIP_CRITICAL) {
 392                dev_emerg(&tz->device,
 393                          "critical temperature reached (%d C), shutting down\n",
 394                          tz->temperature / 1000);
 395                mutex_lock(&poweroff_lock);
 396                if (!power_off_triggered) {
 397                        /*
 398                         * Queue a backup emergency shutdown in the event of
 399                         * orderly_poweroff failure
 400                         */
 401                        thermal_emergency_poweroff();
 402                        orderly_poweroff(true);
 403                        power_off_triggered = true;
 404                }
 405                mutex_unlock(&poweroff_lock);
 406        }
 407}
 408
 409static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 410{
 411        enum thermal_trip_type type;
 412
 413        /* Ignore disabled trip points */
 414        if (test_bit(trip, &tz->trips_disabled))
 415                return;
 416
 417        tz->ops->get_trip_type(tz, trip, &type);
 418
 419        if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 420                handle_critical_trips(tz, trip, type);
 421        else
 422                handle_non_critical_trips(tz, trip, type);
 423        /*
 424         * Alright, we handled this trip successfully.
 425         * So, start monitoring again.
 426         */
 427        monitor_thermal_zone(tz);
 428}
 429
 430static void update_temperature(struct thermal_zone_device *tz)
 431{
 432        int temp, ret;
 433
 434        ret = thermal_zone_get_temp(tz, &temp);
 435        if (ret) {
 436                if (ret != -EAGAIN)
 437                        dev_warn(&tz->device,
 438                                 "failed to read out thermal zone (%d)\n",
 439                                 ret);
 440                return;
 441        }
 442
 443        mutex_lock(&tz->lock);
 444        tz->last_temperature = tz->temperature;
 445        tz->temperature = temp;
 446        mutex_unlock(&tz->lock);
 447
 448        trace_thermal_temperature(tz);
 449        if (tz->last_temperature == THERMAL_TEMP_INVALID)
 450                dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 451                        tz->temperature);
 452        else
 453                dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 454                        tz->last_temperature, tz->temperature);
 455}
 456
 457static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 458{
 459        struct thermal_instance *pos;
 460
 461        tz->temperature = THERMAL_TEMP_INVALID;
 462        tz->passive = 0;
 463        list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 464                pos->initialized = false;
 465}
 466
 467void 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}
 487EXPORT_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 */
 501void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 502{
 503        handle_thermal_trip(tz, trip);
 504}
 505EXPORT_SYMBOL_GPL(thermal_notify_framework);
 506
 507static 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 */
 534int 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 */
 555int 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 */
 583int 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
 605void 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
 625void 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 */
 674int 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 = thermal_cooling_device_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 = thermal_cooling_device_weight_show;
 749        dev->weight_attr.store = thermal_cooling_device_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);
 773remove_trip_file:
 774        device_remove_file(&tz->device, &dev->attr);
 775remove_symbol_link:
 776        sysfs_remove_link(&tz->device.kobj, dev->name);
 777release_ida:
 778        ida_simple_remove(&tz->ida, dev->id);
 779free_mem:
 780        kfree(dev);
 781        return result;
 782}
 783EXPORT_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 */
 799int 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
 821unbind:
 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}
 829EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 830
 831static 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
 848static struct class thermal_class = {
 849        .name = "thermal",
 850        .dev_release = thermal_release,
 851};
 852
 853static inline
 854void 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
 861static 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
 887static 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 */
 941static 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        thermal_cooling_device_setup_sysfs(cdev);
 976        cdev->devdata = devdata;
 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 */
1016struct thermal_cooling_device *
1017thermal_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}
1022EXPORT_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 */
1039struct thermal_cooling_device *
1040thermal_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}
1046EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1047
1048static 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 */
1065void 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_unregister(&cdev->device);
1109}
1110EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1111
1112static void bind_tz(struct thermal_zone_device *tz)
1113{
1114        int i, ret;
1115        struct thermal_cooling_device *pos = NULL;
1116        const struct thermal_zone_params *tzp = tz->tzp;
1117
1118        if (!tzp && !tz->ops->bind)
1119                return;
1120
1121        mutex_lock(&thermal_list_lock);
1122
1123        /* If there is ops->bind, try to use ops->bind */
1124        if (tz->ops->bind) {
1125                list_for_each_entry(pos, &thermal_cdev_list, node) {
1126                        ret = tz->ops->bind(tz, pos);
1127                        if (ret)
1128                                print_bind_err_msg(tz, pos, ret);
1129                }
1130                goto exit;
1131        }
1132
1133        if (!tzp || !tzp->tbp)
1134                goto exit;
1135
1136        list_for_each_entry(pos, &thermal_cdev_list, node) {
1137                for (i = 0; i < tzp->num_tbps; i++) {
1138                        if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1139                                continue;
1140                        if (tzp->tbp[i].match(tz, pos))
1141                                continue;
1142                        tzp->tbp[i].cdev = pos;
1143                        __bind(tz, tzp->tbp[i].trip_mask, pos,
1144                               tzp->tbp[i].binding_limits,
1145                               tzp->tbp[i].weight);
1146                }
1147        }
1148exit:
1149        mutex_unlock(&thermal_list_lock);
1150}
1151
1152/**
1153 * thermal_zone_device_register() - register a new thermal zone device
1154 * @type:       the thermal zone device type
1155 * @trips:      the number of trip points the thermal zone support
1156 * @mask:       a bit string indicating the writeablility of trip points
1157 * @devdata:    private device data
1158 * @ops:        standard thermal zone device callbacks
1159 * @tzp:        thermal zone platform parameters
1160 * @passive_delay: number of milliseconds to wait between polls when
1161 *                 performing passive cooling
1162 * @polling_delay: number of milliseconds to wait between polls when checking
1163 *                 whether trip points have been crossed (0 for interrupt
1164 *                 driven systems)
1165 *
1166 * This interface function adds a new thermal zone device (sensor) to
1167 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1168 * thermal cooling devices registered at the same time.
1169 * thermal_zone_device_unregister() must be called when the device is no
1170 * longer needed. The passive cooling depends on the .get_trend() return value.
1171 *
1172 * Return: a pointer to the created struct thermal_zone_device or an
1173 * in case of error, an ERR_PTR. Caller must check return value with
1174 * IS_ERR*() helpers.
1175 */
1176struct thermal_zone_device *
1177thermal_zone_device_register(const char *type, int trips, int mask,
1178                             void *devdata, struct thermal_zone_device_ops *ops,
1179                             struct thermal_zone_params *tzp, int passive_delay,
1180                             int polling_delay)
1181{
1182        struct thermal_zone_device *tz;
1183        enum thermal_trip_type trip_type;
1184        int trip_temp;
1185        int result;
1186        int count;
1187        struct thermal_governor *governor;
1188
1189        if (!type || strlen(type) == 0)
1190                return ERR_PTR(-EINVAL);
1191
1192        if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1193                return ERR_PTR(-EINVAL);
1194
1195        if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1196                return ERR_PTR(-EINVAL);
1197
1198        if (!ops)
1199                return ERR_PTR(-EINVAL);
1200
1201        if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1202                return ERR_PTR(-EINVAL);
1203
1204        tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1205        if (!tz)
1206                return ERR_PTR(-ENOMEM);
1207
1208        INIT_LIST_HEAD(&tz->thermal_instances);
1209        ida_init(&tz->ida);
1210        mutex_init(&tz->lock);
1211        result = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1212        if (result < 0)
1213                goto free_tz;
1214
1215        tz->id = result;
1216        strlcpy(tz->type, type, sizeof(tz->type));
1217        tz->ops = ops;
1218        tz->tzp = tzp;
1219        tz->device.class = &thermal_class;
1220        tz->devdata = devdata;
1221        tz->trips = trips;
1222        tz->passive_delay = passive_delay;
1223        tz->polling_delay = polling_delay;
1224
1225        /* sys I/F */
1226        /* Add nodes that are always present via .groups */
1227        result = thermal_zone_create_device_groups(tz, mask);
1228        if (result)
1229                goto remove_id;
1230
1231        /* A new thermal zone needs to be updated anyway. */
1232        atomic_set(&tz->need_update, 1);
1233
1234        dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1235        result = device_register(&tz->device);
1236        if (result)
1237                goto remove_device_groups;
1238
1239        for (count = 0; count < trips; count++) {
1240                if (tz->ops->get_trip_type(tz, count, &trip_type))
1241                        set_bit(count, &tz->trips_disabled);
1242                if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1243                        set_bit(count, &tz->trips_disabled);
1244                /* Check for bogus trip points */
1245                if (trip_temp == 0)
1246                        set_bit(count, &tz->trips_disabled);
1247        }
1248
1249        /* Update 'this' zone's governor information */
1250        mutex_lock(&thermal_governor_lock);
1251
1252        if (tz->tzp)
1253                governor = __find_governor(tz->tzp->governor_name);
1254        else
1255                governor = def_governor;
1256
1257        result = thermal_set_governor(tz, governor);
1258        if (result) {
1259                mutex_unlock(&thermal_governor_lock);
1260                goto unregister;
1261        }
1262
1263        mutex_unlock(&thermal_governor_lock);
1264
1265        if (!tz->tzp || !tz->tzp->no_hwmon) {
1266                result = thermal_add_hwmon_sysfs(tz);
1267                if (result)
1268                        goto unregister;
1269        }
1270
1271        mutex_lock(&thermal_list_lock);
1272        list_add_tail(&tz->node, &thermal_tz_list);
1273        mutex_unlock(&thermal_list_lock);
1274
1275        /* Bind cooling devices for this zone */
1276        bind_tz(tz);
1277
1278        INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1279
1280        thermal_zone_device_reset(tz);
1281        /* Update the new thermal zone and mark it as already updated. */
1282        if (atomic_cmpxchg(&tz->need_update, 1, 0))
1283                thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1284
1285        return tz;
1286
1287unregister:
1288        ida_simple_remove(&thermal_tz_ida, tz->id);
1289        device_unregister(&tz->device);
1290        return ERR_PTR(result);
1291
1292remove_device_groups:
1293        thermal_zone_destroy_device_groups(tz);
1294remove_id:
1295        ida_simple_remove(&thermal_tz_ida, tz->id);
1296free_tz:
1297        kfree(tz);
1298        return ERR_PTR(result);
1299}
1300EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1301
1302/**
1303 * thermal_device_unregister - removes the registered thermal zone device
1304 * @tz: the thermal zone device to remove
1305 */
1306void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1307{
1308        int i;
1309        const struct thermal_zone_params *tzp;
1310        struct thermal_cooling_device *cdev;
1311        struct thermal_zone_device *pos = NULL;
1312
1313        if (!tz)
1314                return;
1315
1316        tzp = tz->tzp;
1317
1318        mutex_lock(&thermal_list_lock);
1319        list_for_each_entry(pos, &thermal_tz_list, node)
1320                if (pos == tz)
1321                        break;
1322        if (pos != tz) {
1323                /* thermal zone device not found */
1324                mutex_unlock(&thermal_list_lock);
1325                return;
1326        }
1327        list_del(&tz->node);
1328
1329        /* Unbind all cdevs associated with 'this' thermal zone */
1330        list_for_each_entry(cdev, &thermal_cdev_list, node) {
1331                if (tz->ops->unbind) {
1332                        tz->ops->unbind(tz, cdev);
1333                        continue;
1334                }
1335
1336                if (!tzp || !tzp->tbp)
1337                        break;
1338
1339                for (i = 0; i < tzp->num_tbps; i++) {
1340                        if (tzp->tbp[i].cdev == cdev) {
1341                                __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1342                                tzp->tbp[i].cdev = NULL;
1343                        }
1344                }
1345        }
1346
1347        mutex_unlock(&thermal_list_lock);
1348
1349        thermal_zone_device_set_polling(tz, 0);
1350
1351        thermal_set_governor(tz, NULL);
1352
1353        thermal_remove_hwmon_sysfs(tz);
1354        ida_simple_remove(&thermal_tz_ida, tz->id);
1355        ida_destroy(&tz->ida);
1356        mutex_destroy(&tz->lock);
1357        device_unregister(&tz->device);
1358}
1359EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1360
1361/**
1362 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1363 * @name: thermal zone name to fetch the temperature
1364 *
1365 * When only one zone is found with the passed name, returns a reference to it.
1366 *
1367 * Return: On success returns a reference to an unique thermal zone with
1368 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1369 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1370 */
1371struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1372{
1373        struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1374        unsigned int found = 0;
1375
1376        if (!name)
1377                goto exit;
1378
1379        mutex_lock(&thermal_list_lock);
1380        list_for_each_entry(pos, &thermal_tz_list, node)
1381                if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1382                        found++;
1383                        ref = pos;
1384                }
1385        mutex_unlock(&thermal_list_lock);
1386
1387        /* nothing has been found, thus an error code for it */
1388        if (found == 0)
1389                ref = ERR_PTR(-ENODEV);
1390        else if (found > 1)
1391        /* Success only when an unique zone is found */
1392                ref = ERR_PTR(-EEXIST);
1393
1394exit:
1395        return ref;
1396}
1397EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1398
1399#ifdef CONFIG_NET
1400static const struct genl_multicast_group thermal_event_mcgrps[] = {
1401        { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1402};
1403
1404static struct genl_family thermal_event_genl_family __ro_after_init = {
1405        .module = THIS_MODULE,
1406        .name = THERMAL_GENL_FAMILY_NAME,
1407        .version = THERMAL_GENL_VERSION,
1408        .maxattr = THERMAL_GENL_ATTR_MAX,
1409        .mcgrps = thermal_event_mcgrps,
1410        .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1411};
1412
1413int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1414                                   enum events event)
1415{
1416        struct sk_buff *skb;
1417        struct nlattr *attr;
1418        struct thermal_genl_event *thermal_event;
1419        void *msg_header;
1420        int size;
1421        int result;
1422        static unsigned int thermal_event_seqnum;
1423
1424        if (!tz)
1425                return -EINVAL;
1426
1427        /* allocate memory */
1428        size = nla_total_size(sizeof(struct thermal_genl_event)) +
1429               nla_total_size(0);
1430
1431        skb = genlmsg_new(size, GFP_ATOMIC);
1432        if (!skb)
1433                return -ENOMEM;
1434
1435        /* add the genetlink message header */
1436        msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1437                                 &thermal_event_genl_family, 0,
1438                                 THERMAL_GENL_CMD_EVENT);
1439        if (!msg_header) {
1440                nlmsg_free(skb);
1441                return -ENOMEM;
1442        }
1443
1444        /* fill the data */
1445        attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1446                           sizeof(struct thermal_genl_event));
1447
1448        if (!attr) {
1449                nlmsg_free(skb);
1450                return -EINVAL;
1451        }
1452
1453        thermal_event = nla_data(attr);
1454        if (!thermal_event) {
1455                nlmsg_free(skb);
1456                return -EINVAL;
1457        }
1458
1459        memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1460
1461        thermal_event->orig = tz->id;
1462        thermal_event->event = event;
1463
1464        /* send multicast genetlink message */
1465        genlmsg_end(skb, msg_header);
1466
1467        result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1468                                   0, GFP_ATOMIC);
1469        if (result)
1470                dev_err(&tz->device, "Failed to send netlink event:%d", result);
1471
1472        return result;
1473}
1474EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1475
1476static int __init genetlink_init(void)
1477{
1478        return genl_register_family(&thermal_event_genl_family);
1479}
1480
1481static void genetlink_exit(void)
1482{
1483        genl_unregister_family(&thermal_event_genl_family);
1484}
1485#else /* !CONFIG_NET */
1486static inline int genetlink_init(void) { return 0; }
1487static inline void genetlink_exit(void) {}
1488#endif /* !CONFIG_NET */
1489
1490static int thermal_pm_notify(struct notifier_block *nb,
1491                             unsigned long mode, void *_unused)
1492{
1493        struct thermal_zone_device *tz;
1494
1495        switch (mode) {
1496        case PM_HIBERNATION_PREPARE:
1497        case PM_RESTORE_PREPARE:
1498        case PM_SUSPEND_PREPARE:
1499                atomic_set(&in_suspend, 1);
1500                break;
1501        case PM_POST_HIBERNATION:
1502        case PM_POST_RESTORE:
1503        case PM_POST_SUSPEND:
1504                atomic_set(&in_suspend, 0);
1505                list_for_each_entry(tz, &thermal_tz_list, node) {
1506                        thermal_zone_device_reset(tz);
1507                        thermal_zone_device_update(tz,
1508                                                   THERMAL_EVENT_UNSPECIFIED);
1509                }
1510                break;
1511        default:
1512                break;
1513        }
1514        return 0;
1515}
1516
1517static struct notifier_block thermal_pm_nb = {
1518        .notifier_call = thermal_pm_notify,
1519};
1520
1521static int __init thermal_init(void)
1522{
1523        int result;
1524
1525        mutex_init(&poweroff_lock);
1526        result = thermal_register_governors();
1527        if (result)
1528                goto error;
1529
1530        result = class_register(&thermal_class);
1531        if (result)
1532                goto unregister_governors;
1533
1534        result = genetlink_init();
1535        if (result)
1536                goto unregister_class;
1537
1538        result = of_parse_thermal_zones();
1539        if (result)
1540                goto exit_netlink;
1541
1542        result = register_pm_notifier(&thermal_pm_nb);
1543        if (result)
1544                pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1545                        result);
1546
1547        return 0;
1548
1549exit_netlink:
1550        genetlink_exit();
1551unregister_class:
1552        class_unregister(&thermal_class);
1553unregister_governors:
1554        thermal_unregister_governors();
1555error:
1556        ida_destroy(&thermal_tz_ida);
1557        ida_destroy(&thermal_cdev_ida);
1558        mutex_destroy(&thermal_list_lock);
1559        mutex_destroy(&thermal_governor_lock);
1560        mutex_destroy(&poweroff_lock);
1561        return result;
1562}
1563
1564static void __exit thermal_exit(void)
1565{
1566        unregister_pm_notifier(&thermal_pm_nb);
1567        of_thermal_destroy_zones();
1568        genetlink_exit();
1569        class_unregister(&thermal_class);
1570        thermal_unregister_governors();
1571        ida_destroy(&thermal_tz_ida);
1572        ida_destroy(&thermal_cdev_ida);
1573        mutex_destroy(&thermal_list_lock);
1574        mutex_destroy(&thermal_governor_lock);
1575}
1576
1577fs_initcall(thermal_init);
1578module_exit(thermal_exit);
1579