drivers/thermal/thermal

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This source file includes following definitions.
__find_governor
bind_previous_governor
thermal_set_governor
thermal_register_governor
thermal_unregister_governor
thermal_zone_device_set_policy
thermal_build_list_of_policies
thermal_unregister_governors
thermal_register_governors
thermal_zone_device_set_polling
monitor_thermal_zone
handle_non_critical_trips
thermal_emergency_poweroff_func
thermal_emergency_poweroff
handle_critical_trips
handle_thermal_trip
update_temperature
thermal_zone_device_init
thermal_zone_device_reset
thermal_zone_device_update
thermal_notify_framework
thermal_zone_device_check
power_actor_get_max_power
power_actor_get_min_power
power_actor_set_power
thermal_zone_device_rebind_exception
thermal_zone_device_unbind_exception
thermal_zone_bind_cooling_device
thermal_zone_unbind_cooling_device
thermal_release
print_bind_err_msg
__bind
bind_cdev
__thermal_cooling_device_register
thermal_cooling_device_register
thermal_of_cooling_device_register
thermal_cooling_device_release
devm_thermal_of_cooling_device_register
__unbind
thermal_cooling_device_unregister
bind_tz
thermal_zone_device_register
thermal_zone_device_unregister
thermal_zone_get_zone_by_name
thermal_generate_netlink_event
genetlink_init
genetlink_exit
genetlink_init
genetlink_exit
thermal_pm_notify
thermal_init
   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9 
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11 
  12 #include <linux/module.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <net/netlink.h>
  23 #include <net/genetlink.h>
  24 #include <linux/suspend.h>
  25 
  26 #define CREATE_TRACE_POINTS
  27 #include <trace/events/thermal.h>
  28 
  29 #include "thermal_core.h"
  30 #include "thermal_hwmon.h"
  31 
  32 MODULE_AUTHOR("Zhang Rui");
  33 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  34 MODULE_LICENSE("GPL v2");
  35 
  36 static DEFINE_IDA(thermal_tz_ida);
  37 static DEFINE_IDA(thermal_cdev_ida);
  38 
  39 static LIST_HEAD(thermal_tz_list);
  40 static LIST_HEAD(thermal_cdev_list);
  41 static LIST_HEAD(thermal_governor_list);
  42 
  43 static DEFINE_MUTEX(thermal_list_lock);
  44 static DEFINE_MUTEX(thermal_governor_lock);
  45 static DEFINE_MUTEX(poweroff_lock);
  46 
  47 static atomic_t in_suspend;
  48 static bool power_off_triggered;
  49 
  50 static struct thermal_governor *def_governor;
  51 
  52 /*
  53  * Governor section: set of functions to handle thermal governors
  54  *
  55  * Functions to help in the life cycle of thermal governors within
  56  * the thermal core and by the thermal governor code.
  57  */
  58 
  59 static struct thermal_governor *__find_governor(const char *name)
  60 {
  61         struct thermal_governor *pos;
  62 
  63         if (!name || !name[0])
  64                 return def_governor;
  65 
  66         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  67                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  68                         return pos;
  69 
  70         return NULL;
  71 }
  72 
  73 /**
  74  * bind_previous_governor() - bind the previous governor of the thermal zone
  75  * @tz:         a valid pointer to a struct thermal_zone_device
  76  * @failed_gov_name:    the name of the governor that failed to register
  77  *
  78  * Register the previous governor of the thermal zone after a new
  79  * governor has failed to be bound.
  80  */
  81 static void bind_previous_governor(struct thermal_zone_device *tz,
  82                                    const char *failed_gov_name)
  83 {
  84         if (tz->governor && tz->governor->bind_to_tz) {
  85                 if (tz->governor->bind_to_tz(tz)) {
  86                         dev_err(&tz->device,
  87                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  88                                 failed_gov_name, tz->governor->name, tz->type);
  89                         tz->governor = NULL;
  90                 }
  91         }
  92 }
  93 
  94 /**
  95  * thermal_set_governor() - Switch to another governor
  96  * @tz:         a valid pointer to a struct thermal_zone_device
  97  * @new_gov:    pointer to the new governor
  98  *
  99  * Change the governor of thermal zone @tz.
 100  *
 101  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 102  */
 103 static int thermal_set_governor(struct thermal_zone_device *tz,
 104                                 struct thermal_governor *new_gov)
 105 {
 106         int ret = 0;
 107 
 108         if (tz->governor && tz->governor->unbind_from_tz)
 109                 tz->governor->unbind_from_tz(tz);
 110 
 111         if (new_gov && new_gov->bind_to_tz) {
 112                 ret = new_gov->bind_to_tz(tz);
 113                 if (ret) {
 114                         bind_previous_governor(tz, new_gov->name);
 115 
 116                         return ret;
 117                 }
 118         }
 119 
 120         tz->governor = new_gov;
 121 
 122         return ret;
 123 }
 124 
 125 int thermal_register_governor(struct thermal_governor *governor)
 126 {
 127         int err;
 128         const char *name;
 129         struct thermal_zone_device *pos;
 130 
 131         if (!governor)
 132                 return -EINVAL;
 133 
 134         mutex_lock(&thermal_governor_lock);
 135 
 136         err = -EBUSY;
 137         if (!__find_governor(governor->name)) {
 138                 bool match_default;
 139 
 140                 err = 0;
 141                 list_add(&governor->governor_list, &thermal_governor_list);
 142                 match_default = !strncmp(governor->name,
 143                                          DEFAULT_THERMAL_GOVERNOR,
 144                                          THERMAL_NAME_LENGTH);
 145 
 146                 if (!def_governor && match_default)
 147                         def_governor = governor;
 148         }
 149 
 150         mutex_lock(&thermal_list_lock);
 151 
 152         list_for_each_entry(pos, &thermal_tz_list, node) {
 153                 /*
 154                  * only thermal zones with specified tz->tzp->governor_name
 155                  * may run with tz->govenor unset
 156                  */
 157                 if (pos->governor)
 158                         continue;
 159 
 160                 name = pos->tzp->governor_name;
 161 
 162                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 163                         int ret;
 164 
 165                         ret = thermal_set_governor(pos, governor);
 166                         if (ret)
 167                                 dev_err(&pos->device,
 168                                         "Failed to set governor %s for thermal zone %s: %d\n",
 169                                         governor->name, pos->type, ret);
 170                 }
 171         }
 172 
 173         mutex_unlock(&thermal_list_lock);
 174         mutex_unlock(&thermal_governor_lock);
 175 
 176         return err;
 177 }
 178 
 179 void thermal_unregister_governor(struct thermal_governor *governor)
 180 {
 181         struct thermal_zone_device *pos;
 182 
 183         if (!governor)
 184                 return;
 185 
 186         mutex_lock(&thermal_governor_lock);
 187 
 188         if (!__find_governor(governor->name))
 189                 goto exit;
 190 
 191         mutex_lock(&thermal_list_lock);
 192 
 193         list_for_each_entry(pos, &thermal_tz_list, node) {
 194                 if (!strncasecmp(pos->governor->name, governor->name,
 195                                  THERMAL_NAME_LENGTH))
 196                         thermal_set_governor(pos, NULL);
 197         }
 198 
 199         mutex_unlock(&thermal_list_lock);
 200         list_del(&governor->governor_list);
 201 exit:
 202         mutex_unlock(&thermal_governor_lock);
 203 }
 204 
 205 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 206                                    char *policy)
 207 {
 208         struct thermal_governor *gov;
 209         int ret = -EINVAL;
 210 
 211         mutex_lock(&thermal_governor_lock);
 212         mutex_lock(&tz->lock);
 213 
 214         gov = __find_governor(strim(policy));
 215         if (!gov)
 216                 goto exit;
 217 
 218         ret = thermal_set_governor(tz, gov);
 219 
 220 exit:
 221         mutex_unlock(&tz->lock);
 222         mutex_unlock(&thermal_governor_lock);
 223 
 224         return ret;
 225 }
 226 
 227 int thermal_build_list_of_policies(char *buf)
 228 {
 229         struct thermal_governor *pos;
 230         ssize_t count = 0;
 231         ssize_t size = PAGE_SIZE;
 232 
 233         mutex_lock(&thermal_governor_lock);
 234 
 235         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 236                 size = PAGE_SIZE - count;
 237                 count += scnprintf(buf + count, size, "%s ", pos->name);
 238         }
 239         count += scnprintf(buf + count, size, "\n");
 240 
 241         mutex_unlock(&thermal_governor_lock);
 242 
 243         return count;
 244 }
 245 
 246 static void __init thermal_unregister_governors(void)
 247 {
 248         struct thermal_governor **governor;
 249 
 250         for_each_governor_table(governor)
 251                 thermal_unregister_governor(*governor);
 252 }
 253 
 254 static int __init thermal_register_governors(void)
 255 {
 256         int ret = 0;
 257         struct thermal_governor **governor;
 258 
 259         for_each_governor_table(governor) {
 260                 ret = thermal_register_governor(*governor);
 261                 if (ret) {
 262                         pr_err("Failed to register governor: '%s'",
 263                                (*governor)->name);
 264                         break;
 265                 }
 266 
 267                 pr_info("Registered thermal governor '%s'",
 268                         (*governor)->name);
 269         }
 270 
 271         if (ret) {
 272                 struct thermal_governor **gov;
 273 
 274                 for_each_governor_table(gov) {
 275                         if (gov == governor)
 276                                 break;
 277                         thermal_unregister_governor(*gov);
 278                 }
 279         }
 280 
 281         return ret;
 282 }
 283 
 284 /*
 285  * Zone update section: main control loop applied to each zone while monitoring
 286  *
 287  * in polling mode. The monitoring is done using a workqueue.
 288  * Same update may be done on a zone by calling thermal_zone_device_update().
 289  *
 290  * An update means:
 291  * - Non-critical trips will invoke the governor responsible for that zone;
 292  * - Hot trips will produce a notification to userspace;
 293  * - Critical trip point will cause a system shutdown.
 294  */
 295 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 296                                             int delay)
 297 {
 298         if (delay > 1000)
 299                 mod_delayed_work(system_freezable_power_efficient_wq,
 300                                  &tz->poll_queue,
 301                                  round_jiffies(msecs_to_jiffies(delay)));
 302         else if (delay)
 303                 mod_delayed_work(system_freezable_power_efficient_wq,
 304                                  &tz->poll_queue,
 305                                  msecs_to_jiffies(delay));
 306         else
 307                 cancel_delayed_work(&tz->poll_queue);
 308 }
 309 
 310 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 311 {
 312         mutex_lock(&tz->lock);
 313 
 314         if (tz->passive)
 315                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 316         else if (tz->polling_delay)
 317                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 318         else
 319                 thermal_zone_device_set_polling(tz, 0);
 320 
 321         mutex_unlock(&tz->lock);
 322 }
 323 
 324 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 325 {
 326         tz->governor ? tz->governor->throttle(tz, trip) :
 327                        def_governor->throttle(tz, trip);
 328 }
 329 
 330 /**
 331  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 332  * @work: work_struct associated with the emergency poweroff function
 333  *
 334  * This function is called in very critical situations to force
 335  * a kernel poweroff after a configurable timeout value.
 336  */
 337 static void thermal_emergency_poweroff_func(struct work_struct *work)
 338 {
 339         /*
 340          * We have reached here after the emergency thermal shutdown
 341          * Waiting period has expired. This means orderly_poweroff has
 342          * not been able to shut off the system for some reason.
 343          * Try to shut down the system immediately using kernel_power_off
 344          * if populated
 345          */
 346         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 347         kernel_power_off();
 348 
 349         /*
 350          * Worst of the worst case trigger emergency restart
 351          */
 352         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 353         emergency_restart();
 354 }
 355 
 356 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 357                             thermal_emergency_poweroff_func);
 358 
 359 /**
 360  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 361  *
 362  * This may be called from any critical situation to trigger a system shutdown
 363  * after a known period of time. By default this is not scheduled.
 364  */
 365 static void thermal_emergency_poweroff(void)
 366 {
 367         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 368         /*
 369          * poweroff_delay_ms must be a carefully profiled positive value.
 370          * Its a must for thermal_emergency_poweroff_work to be scheduled
 371          */
 372         if (poweroff_delay_ms <= 0)
 373                 return;
 374         schedule_delayed_work(&thermal_emergency_poweroff_work,
 375                               msecs_to_jiffies(poweroff_delay_ms));
 376 }
 377 
 378 static void handle_critical_trips(struct thermal_zone_device *tz,
 379                                   int trip, enum thermal_trip_type trip_type)
 380 {
 381         int trip_temp;
 382 
 383         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 384 
 385         /* If we have not crossed the trip_temp, we do not care. */
 386         if (trip_temp <= 0 || tz->temperature < trip_temp)
 387                 return;
 388 
 389         trace_thermal_zone_trip(tz, trip, trip_type);
 390 
 391         if (tz->ops->notify)
 392                 tz->ops->notify(tz, trip, trip_type);
 393 
 394         if (trip_type == THERMAL_TRIP_CRITICAL) {
 395                 dev_emerg(&tz->device,
 396                           "critical temperature reached (%d C), shutting down\n",
 397                           tz->temperature / 1000);
 398                 mutex_lock(&poweroff_lock);
 399                 if (!power_off_triggered) {
 400                         /*
 401                          * Queue a backup emergency shutdown in the event of
 402                          * orderly_poweroff failure
 403                          */
 404                         thermal_emergency_poweroff();
 405                         orderly_poweroff(true);
 406                         power_off_triggered = true;
 407                 }
 408                 mutex_unlock(&poweroff_lock);
 409         }
 410 }
 411 
 412 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 413 {
 414         enum thermal_trip_type type;
 415 
 416         /* Ignore disabled trip points */
 417         if (test_bit(trip, &tz->trips_disabled))
 418                 return;
 419 
 420         tz->ops->get_trip_type(tz, trip, &type);
 421 
 422         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 423                 handle_critical_trips(tz, trip, type);
 424         else
 425                 handle_non_critical_trips(tz, trip);
 426         /*
 427          * Alright, we handled this trip successfully.
 428          * So, start monitoring again.
 429          */
 430         monitor_thermal_zone(tz);
 431 }
 432 
 433 static void update_temperature(struct thermal_zone_device *tz)
 434 {
 435         int temp, ret;
 436 
 437         ret = thermal_zone_get_temp(tz, &temp);
 438         if (ret) {
 439                 if (ret != -EAGAIN)
 440                         dev_warn(&tz->device,
 441                                  "failed to read out thermal zone (%d)\n",
 442                                  ret);
 443                 return;
 444         }
 445 
 446         mutex_lock(&tz->lock);
 447         tz->last_temperature = tz->temperature;
 448         tz->temperature = temp;
 449         mutex_unlock(&tz->lock);
 450 
 451         trace_thermal_temperature(tz);
 452         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 453                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 454                         tz->temperature);
 455         else
 456                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 457                         tz->last_temperature, tz->temperature);
 458 }
 459 
 460 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 461 {
 462         struct thermal_instance *pos;
 463         tz->temperature = THERMAL_TEMP_INVALID;
 464         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 465                 pos->initialized = false;
 466 }
 467 
 468 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 469 {
 470         tz->passive = 0;
 471         thermal_zone_device_init(tz);
 472 }
 473 
 474 void thermal_zone_device_update(struct thermal_zone_device *tz,
 475                                 enum thermal_notify_event event)
 476 {
 477         int count;
 478 
 479         if (atomic_read(&in_suspend))
 480                 return;
 481 
 482         if (!tz->ops->get_temp)
 483                 return;
 484 
 485         update_temperature(tz);
 486 
 487         thermal_zone_set_trips(tz);
 488 
 489         tz->notify_event = event;
 490 
 491         for (count = 0; count < tz->trips; count++)
 492                 handle_thermal_trip(tz, count);
 493 }
 494 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 495 
 496 /**
 497  * thermal_notify_framework - Sensor drivers use this API to notify framework
 498  * @tz:         thermal zone device
 499  * @trip:       indicates which trip point has been crossed
 500  *
 501  * This function handles the trip events from sensor drivers. It starts
 502  * throttling the cooling devices according to the policy configured.
 503  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 504  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 505  * The throttling policy is based on the configured platform data; if no
 506  * platform data is provided, this uses the step_wise throttling policy.
 507  */
 508 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 509 {
 510         handle_thermal_trip(tz, trip);
 511 }
 512 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 513 
 514 static void thermal_zone_device_check(struct work_struct *work)
 515 {
 516         struct thermal_zone_device *tz = container_of(work, struct
 517                                                       thermal_zone_device,
 518                                                       poll_queue.work);
 519         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 520 }
 521 
 522 /*
 523  * Power actor section: interface to power actors to estimate power
 524  *
 525  * Set of functions used to interact to cooling devices that know
 526  * how to estimate their devices power consumption.
 527  */
 528 
 529 /**
 530  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 531  * @cdev:       pointer to &thermal_cooling_device
 532  * @tz:         a valid thermal zone device pointer
 533  * @max_power:  pointer in which to store the maximum power
 534  *
 535  * Calculate the maximum power consumption in milliwats that the
 536  * cooling device can currently consume and store it in @max_power.
 537  *
 538  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 539  * power_actor API or -E* on other error.
 540  */
 541 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 542                               struct thermal_zone_device *tz, u32 *max_power)
 543 {
 544         if (!cdev_is_power_actor(cdev))
 545                 return -EINVAL;
 546 
 547         return cdev->ops->state2power(cdev, tz, 0, max_power);
 548 }
 549 
 550 /**
 551  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 552  * @cdev:       pointer to &thermal_cooling_device
 553  * @tz:         a valid thermal zone device pointer
 554  * @min_power:  pointer in which to store the minimum power
 555  *
 556  * Calculate the minimum power consumption in milliwatts that the
 557  * cooling device can currently consume and store it in @min_power.
 558  *
 559  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 560  * power_actor API or -E* on other error.
 561  */
 562 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 563                               struct thermal_zone_device *tz, u32 *min_power)
 564 {
 565         unsigned long max_state;
 566         int ret;
 567 
 568         if (!cdev_is_power_actor(cdev))
 569                 return -EINVAL;
 570 
 571         ret = cdev->ops->get_max_state(cdev, &max_state);
 572         if (ret)
 573                 return ret;
 574 
 575         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 576 }
 577 
 578 /**
 579  * power_actor_set_power() - limit the maximum power a cooling device consumes
 580  * @cdev:       pointer to &thermal_cooling_device
 581  * @instance:   thermal instance to update
 582  * @power:      the power in milliwatts
 583  *
 584  * Set the cooling device to consume at most @power milliwatts. The limit is
 585  * expected to be a cap at the maximum power consumption.
 586  *
 587  * Return: 0 on success, -EINVAL if the cooling device does not
 588  * implement the power actor API or -E* for other failures.
 589  */
 590 int power_actor_set_power(struct thermal_cooling_device *cdev,
 591                           struct thermal_instance *instance, u32 power)
 592 {
 593         unsigned long state;
 594         int ret;
 595 
 596         if (!cdev_is_power_actor(cdev))
 597                 return -EINVAL;
 598 
 599         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 600         if (ret)
 601                 return ret;
 602 
 603         instance->target = state;
 604         mutex_lock(&cdev->lock);
 605         cdev->updated = false;
 606         mutex_unlock(&cdev->lock);
 607         thermal_cdev_update(cdev);
 608 
 609         return 0;
 610 }
 611 
 612 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 613                                           const char *cdev_type, size_t size)
 614 {
 615         struct thermal_cooling_device *cdev = NULL;
 616 
 617         mutex_lock(&thermal_list_lock);
 618         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 619                 /* skip non matching cdevs */
 620                 if (strncmp(cdev_type, cdev->type, size))
 621                         continue;
 622 
 623                 /* re binding the exception matching the type pattern */
 624                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 625                                                  THERMAL_NO_LIMIT,
 626                                                  THERMAL_NO_LIMIT,
 627                                                  THERMAL_WEIGHT_DEFAULT);
 628         }
 629         mutex_unlock(&thermal_list_lock);
 630 }
 631 
 632 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 633                                           const char *cdev_type, size_t size)
 634 {
 635         struct thermal_cooling_device *cdev = NULL;
 636 
 637         mutex_lock(&thermal_list_lock);
 638         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 639                 /* skip non matching cdevs */
 640                 if (strncmp(cdev_type, cdev->type, size))
 641                         continue;
 642                 /* unbinding the exception matching the type pattern */
 643                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 644                                                    cdev);
 645         }
 646         mutex_unlock(&thermal_list_lock);
 647 }
 648 
 649 /*
 650  * Device management section: cooling devices, zones devices, and binding
 651  *
 652  * Set of functions provided by the thermal core for:
 653  * - cooling devices lifecycle: registration, unregistration,
 654  *                              binding, and unbinding.
 655  * - thermal zone devices lifecycle: registration, unregistration,
 656  *                                   binding, and unbinding.
 657  */
 658 
 659 /**
 660  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 661  * @tz:         pointer to struct thermal_zone_device
 662  * @trip:       indicates which trip point the cooling devices is
 663  *              associated with in this thermal zone.
 664  * @cdev:       pointer to struct thermal_cooling_device
 665  * @upper:      the Maximum cooling state for this trip point.
 666  *              THERMAL_NO_LIMIT means no upper limit,
 667  *              and the cooling device can be in max_state.
 668  * @lower:      the Minimum cooling state can be used for this trip point.
 669  *              THERMAL_NO_LIMIT means no lower limit,
 670  *              and the cooling device can be in cooling state 0.
 671  * @weight:     The weight of the cooling device to be bound to the
 672  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 673  *              default value
 674  *
 675  * This interface function bind a thermal cooling device to the certain trip
 676  * point of a thermal zone device.
 677  * This function is usually called in the thermal zone device .bind callback.
 678  *
 679  * Return: 0 on success, the proper error value otherwise.
 680  */
 681 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 682                                      int trip,
 683                                      struct thermal_cooling_device *cdev,
 684                                      unsigned long upper, unsigned long lower,
 685                                      unsigned int weight)
 686 {
 687         struct thermal_instance *dev;
 688         struct thermal_instance *pos;
 689         struct thermal_zone_device *pos1;
 690         struct thermal_cooling_device *pos2;
 691         unsigned long max_state;
 692         int result, ret;
 693 
 694         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 695                 return -EINVAL;
 696 
 697         list_for_each_entry(pos1, &thermal_tz_list, node) {
 698                 if (pos1 == tz)
 699                         break;
 700         }
 701         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 702                 if (pos2 == cdev)
 703                         break;
 704         }
 705 
 706         if (tz != pos1 || cdev != pos2)
 707                 return -EINVAL;
 708 
 709         ret = cdev->ops->get_max_state(cdev, &max_state);
 710         if (ret)
 711                 return ret;
 712 
 713         /* lower default 0, upper default max_state */
 714         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 715         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 716 
 717         if (lower > upper || upper > max_state)
 718                 return -EINVAL;
 719 
 720         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 721         if (!dev)
 722                 return -ENOMEM;
 723         dev->tz = tz;
 724         dev->cdev = cdev;
 725         dev->trip = trip;
 726         dev->upper = upper;
 727         dev->lower = lower;
 728         dev->target = THERMAL_NO_TARGET;
 729         dev->weight = weight;
 730 
 731         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 732         if (result < 0)
 733                 goto free_mem;
 734 
 735         dev->id = result;
 736         sprintf(dev->name, "cdev%d", dev->id);
 737         result =
 738             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 739         if (result)
 740                 goto release_ida;
 741 
 742         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 743         sysfs_attr_init(&dev->attr.attr);
 744         dev->attr.attr.name = dev->attr_name;
 745         dev->attr.attr.mode = 0444;
 746         dev->attr.show = trip_point_show;
 747         result = device_create_file(&tz->device, &dev->attr);
 748         if (result)
 749                 goto remove_symbol_link;
 750 
 751         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 752         sysfs_attr_init(&dev->weight_attr.attr);
 753         dev->weight_attr.attr.name = dev->weight_attr_name;
 754         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 755         dev->weight_attr.show = weight_show;
 756         dev->weight_attr.store = weight_store;
 757         result = device_create_file(&tz->device, &dev->weight_attr);
 758         if (result)
 759                 goto remove_trip_file;
 760 
 761         mutex_lock(&tz->lock);
 762         mutex_lock(&cdev->lock);
 763         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 764                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 765                         result = -EEXIST;
 766                         break;
 767                 }
 768         if (!result) {
 769                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 770                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 771                 atomic_set(&tz->need_update, 1);
 772         }
 773         mutex_unlock(&cdev->lock);
 774         mutex_unlock(&tz->lock);
 775 
 776         if (!result)
 777                 return 0;
 778 
 779         device_remove_file(&tz->device, &dev->weight_attr);
 780 remove_trip_file:
 781         device_remove_file(&tz->device, &dev->attr);
 782 remove_symbol_link:
 783         sysfs_remove_link(&tz->device.kobj, dev->name);
 784 release_ida:
 785         ida_simple_remove(&tz->ida, dev->id);
 786 free_mem:
 787         kfree(dev);
 788         return result;
 789 }
 790 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 791 
 792 /**
 793  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 794  *                                        thermal zone.
 795  * @tz:         pointer to a struct thermal_zone_device.
 796  * @trip:       indicates which trip point the cooling devices is
 797  *              associated with in this thermal zone.
 798  * @cdev:       pointer to a struct thermal_cooling_device.
 799  *
 800  * This interface function unbind a thermal cooling device from the certain
 801  * trip point of a thermal zone device.
 802  * This function is usually called in the thermal zone device .unbind callback.
 803  *
 804  * Return: 0 on success, the proper error value otherwise.
 805  */
 806 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 807                                        int trip,
 808                                        struct thermal_cooling_device *cdev)
 809 {
 810         struct thermal_instance *pos, *next;
 811 
 812         mutex_lock(&tz->lock);
 813         mutex_lock(&cdev->lock);
 814         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 815                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 816                         list_del(&pos->tz_node);
 817                         list_del(&pos->cdev_node);
 818                         mutex_unlock(&cdev->lock);
 819                         mutex_unlock(&tz->lock);
 820                         goto unbind;
 821                 }
 822         }
 823         mutex_unlock(&cdev->lock);
 824         mutex_unlock(&tz->lock);
 825 
 826         return -ENODEV;
 827 
 828 unbind:
 829         device_remove_file(&tz->device, &pos->weight_attr);
 830         device_remove_file(&tz->device, &pos->attr);
 831         sysfs_remove_link(&tz->device.kobj, pos->name);
 832         ida_simple_remove(&tz->ida, pos->id);
 833         kfree(pos);
 834         return 0;
 835 }
 836 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 837 
 838 static void thermal_release(struct device *dev)
 839 {
 840         struct thermal_zone_device *tz;
 841         struct thermal_cooling_device *cdev;
 842 
 843         if (!strncmp(dev_name(dev), "thermal_zone",
 844                      sizeof("thermal_zone") - 1)) {
 845                 tz = to_thermal_zone(dev);
 846                 thermal_zone_destroy_device_groups(tz);
 847                 kfree(tz);
 848         } else if (!strncmp(dev_name(dev), "cooling_device",
 849                             sizeof("cooling_device") - 1)) {
 850                 cdev = to_cooling_device(dev);
 851                 kfree(cdev);
 852         }
 853 }
 854 
 855 static struct class thermal_class = {
 856         .name = "thermal",
 857         .dev_release = thermal_release,
 858 };
 859 
 860 static inline
 861 void print_bind_err_msg(struct thermal_zone_device *tz,
 862                         struct thermal_cooling_device *cdev, int ret)
 863 {
 864         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 865                 tz->type, cdev->type, ret);
 866 }
 867 
 868 static void __bind(struct thermal_zone_device *tz, int mask,
 869                    struct thermal_cooling_device *cdev,
 870                    unsigned long *limits,
 871                    unsigned int weight)
 872 {
 873         int i, ret;
 874 
 875         for (i = 0; i < tz->trips; i++) {
 876                 if (mask & (1 << i)) {
 877                         unsigned long upper, lower;
 878 
 879                         upper = THERMAL_NO_LIMIT;
 880                         lower = THERMAL_NO_LIMIT;
 881                         if (limits) {
 882                                 lower = limits[i * 2];
 883                                 upper = limits[i * 2 + 1];
 884                         }
 885                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 886                                                                upper, lower,
 887                                                                weight);
 888                         if (ret)
 889                                 print_bind_err_msg(tz, cdev, ret);
 890                 }
 891         }
 892 }
 893 
 894 static void bind_cdev(struct thermal_cooling_device *cdev)
 895 {
 896         int i, ret;
 897         const struct thermal_zone_params *tzp;
 898         struct thermal_zone_device *pos = NULL;
 899 
 900         mutex_lock(&thermal_list_lock);
 901 
 902         list_for_each_entry(pos, &thermal_tz_list, node) {
 903                 if (!pos->tzp && !pos->ops->bind)
 904                         continue;
 905 
 906                 if (pos->ops->bind) {
 907                         ret = pos->ops->bind(pos, cdev);
 908                         if (ret)
 909                                 print_bind_err_msg(pos, cdev, ret);
 910                         continue;
 911                 }
 912 
 913                 tzp = pos->tzp;
 914                 if (!tzp || !tzp->tbp)
 915                         continue;
 916 
 917                 for (i = 0; i < tzp->num_tbps; i++) {
 918                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 919                                 continue;
 920                         if (tzp->tbp[i].match(pos, cdev))
 921                                 continue;
 922                         tzp->tbp[i].cdev = cdev;
 923                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 924                                tzp->tbp[i].binding_limits,
 925                                tzp->tbp[i].weight);
 926                 }
 927         }
 928 
 929         mutex_unlock(&thermal_list_lock);
 930 }
 931 
 932 /**
 933  * __thermal_cooling_device_register() - register a new thermal cooling device
 934  * @np:         a pointer to a device tree node.
 935  * @type:       the thermal cooling device type.
 936  * @devdata:    device private data.
 937  * @ops:                standard thermal cooling devices callbacks.
 938  *
 939  * This interface function adds a new thermal cooling device (fan/processor/...)
 940  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 941  * to all the thermal zone devices registered at the same time.
 942  * It also gives the opportunity to link the cooling device to a device tree
 943  * node, so that it can be bound to a thermal zone created out of device tree.
 944  *
 945  * Return: a pointer to the created struct thermal_cooling_device or an
 946  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 947  */
 948 static struct thermal_cooling_device *
 949 __thermal_cooling_device_register(struct device_node *np,
 950                                   const char *type, void *devdata,
 951                                   const struct thermal_cooling_device_ops *ops)
 952 {
 953         struct thermal_cooling_device *cdev;
 954         struct thermal_zone_device *pos = NULL;
 955         int result;
 956 
 957         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 958                 return ERR_PTR(-EINVAL);
 959 
 960         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 961             !ops->set_cur_state)
 962                 return ERR_PTR(-EINVAL);
 963 
 964         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 965         if (!cdev)
 966                 return ERR_PTR(-ENOMEM);
 967 
 968         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 969         if (result < 0) {
 970                 kfree(cdev);
 971                 return ERR_PTR(result);
 972         }
 973 
 974         cdev->id = result;
 975         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 976         mutex_init(&cdev->lock);
 977         INIT_LIST_HEAD(&cdev->thermal_instances);
 978         cdev->np = np;
 979         cdev->ops = ops;
 980         cdev->updated = false;
 981         cdev->device.class = &thermal_class;
 982         cdev->devdata = devdata;
 983         thermal_cooling_device_setup_sysfs(cdev);
 984         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 985         result = device_register(&cdev->device);
 986         if (result) {
 987                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 988                 put_device(&cdev->device);
 989                 return ERR_PTR(result);
 990         }
 991 
 992         /* Add 'this' new cdev to the global cdev list */
 993         mutex_lock(&thermal_list_lock);
 994         list_add(&cdev->node, &thermal_cdev_list);
 995         mutex_unlock(&thermal_list_lock);
 996 
 997         /* Update binding information for 'this' new cdev */
 998         bind_cdev(cdev);
 999 
1000         mutex_lock(&thermal_list_lock);
1001         list_for_each_entry(pos, &thermal_tz_list, node)
1002                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1003                         thermal_zone_device_update(pos,
1004                                                    THERMAL_EVENT_UNSPECIFIED);
1005         mutex_unlock(&thermal_list_lock);
1006 
1007         return cdev;
1008 }
1009 
1010 /**
1011  * thermal_cooling_device_register() - register a new thermal cooling device
1012  * @type:       the thermal cooling device type.
1013  * @devdata:    device private data.
1014  * @ops:                standard thermal cooling devices callbacks.
1015  *
1016  * This interface function adds a new thermal cooling device (fan/processor/...)
1017  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1018  * to all the thermal zone devices registered at the same time.
1019  *
1020  * Return: a pointer to the created struct thermal_cooling_device or an
1021  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1022  */
1023 struct thermal_cooling_device *
1024 thermal_cooling_device_register(const char *type, void *devdata,
1025                                 const struct thermal_cooling_device_ops *ops)
1026 {
1027         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1028 }
1029 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1030 
1031 /**
1032  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1033  * @np:         a pointer to a device tree node.
1034  * @type:       the thermal cooling device type.
1035  * @devdata:    device private data.
1036  * @ops:                standard thermal cooling devices callbacks.
1037  *
1038  * This function will register a cooling device with device tree node reference.
1039  * This interface function adds a new thermal cooling device (fan/processor/...)
1040  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1041  * to all the thermal zone devices registered at the same time.
1042  *
1043  * Return: a pointer to the created struct thermal_cooling_device or an
1044  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1045  */
1046 struct thermal_cooling_device *
1047 thermal_of_cooling_device_register(struct device_node *np,
1048                                    const char *type, void *devdata,
1049                                    const struct thermal_cooling_device_ops *ops)
1050 {
1051         return __thermal_cooling_device_register(np, type, devdata, ops);
1052 }
1053 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1054 
1055 static void thermal_cooling_device_release(struct device *dev, void *res)
1056 {
1057         thermal_cooling_device_unregister(
1058                                 *(struct thermal_cooling_device **)res);
1059 }
1060 
1061 /**
1062  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1063  *                                             device
1064  * @dev:        a valid struct device pointer of a sensor device.
1065  * @np:         a pointer to a device tree node.
1066  * @type:       the thermal cooling device type.
1067  * @devdata:    device private data.
1068  * @ops:        standard thermal cooling devices callbacks.
1069  *
1070  * This function will register a cooling device with device tree node reference.
1071  * This interface function adds a new thermal cooling device (fan/processor/...)
1072  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1073  * to all the thermal zone devices registered at the same time.
1074  *
1075  * Return: a pointer to the created struct thermal_cooling_device or an
1076  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1077  */
1078 struct thermal_cooling_device *
1079 devm_thermal_of_cooling_device_register(struct device *dev,
1080                                 struct device_node *np,
1081                                 char *type, void *devdata,
1082                                 const struct thermal_cooling_device_ops *ops)
1083 {
1084         struct thermal_cooling_device **ptr, *tcd;
1085 
1086         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1087                            GFP_KERNEL);
1088         if (!ptr)
1089                 return ERR_PTR(-ENOMEM);
1090 
1091         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1092         if (IS_ERR(tcd)) {
1093                 devres_free(ptr);
1094                 return tcd;
1095         }
1096 
1097         *ptr = tcd;
1098         devres_add(dev, ptr);
1099 
1100         return tcd;
1101 }
1102 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1103 
1104 static void __unbind(struct thermal_zone_device *tz, int mask,
1105                      struct thermal_cooling_device *cdev)
1106 {
1107         int i;
1108 
1109         for (i = 0; i < tz->trips; i++)
1110                 if (mask & (1 << i))
1111                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1112 }
1113 
1114 /**
1115  * thermal_cooling_device_unregister - removes a thermal cooling device
1116  * @cdev:       the thermal cooling device to remove.
1117  *
1118  * thermal_cooling_device_unregister() must be called when a registered
1119  * thermal cooling device is no longer needed.
1120  */
1121 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1122 {
1123         int i;
1124         const struct thermal_zone_params *tzp;
1125         struct thermal_zone_device *tz;
1126         struct thermal_cooling_device *pos = NULL;
1127 
1128         if (!cdev)
1129                 return;
1130 
1131         mutex_lock(&thermal_list_lock);
1132         list_for_each_entry(pos, &thermal_cdev_list, node)
1133                 if (pos == cdev)
1134                         break;
1135         if (pos != cdev) {
1136                 /* thermal cooling device not found */
1137                 mutex_unlock(&thermal_list_lock);
1138                 return;
1139         }
1140         list_del(&cdev->node);
1141 
1142         /* Unbind all thermal zones associated with 'this' cdev */
1143         list_for_each_entry(tz, &thermal_tz_list, node) {
1144                 if (tz->ops->unbind) {
1145                         tz->ops->unbind(tz, cdev);
1146                         continue;
1147                 }
1148 
1149                 if (!tz->tzp || !tz->tzp->tbp)
1150                         continue;
1151 
1152                 tzp = tz->tzp;
1153                 for (i = 0; i < tzp->num_tbps; i++) {
1154                         if (tzp->tbp[i].cdev == cdev) {
1155                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1156                                 tzp->tbp[i].cdev = NULL;
1157                         }
1158                 }
1159         }
1160 
1161         mutex_unlock(&thermal_list_lock);
1162 
1163         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1164         device_del(&cdev->device);
1165         thermal_cooling_device_destroy_sysfs(cdev);
1166         put_device(&cdev->device);
1167 }
1168 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1169 
1170 static void bind_tz(struct thermal_zone_device *tz)
1171 {
1172         int i, ret;
1173         struct thermal_cooling_device *pos = NULL;
1174         const struct thermal_zone_params *tzp = tz->tzp;
1175 
1176         if (!tzp && !tz->ops->bind)
1177                 return;
1178 
1179         mutex_lock(&thermal_list_lock);
1180 
1181         /* If there is ops->bind, try to use ops->bind */
1182         if (tz->ops->bind) {
1183                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1184                         ret = tz->ops->bind(tz, pos);
1185                         if (ret)
1186                                 print_bind_err_msg(tz, pos, ret);
1187                 }
1188                 goto exit;
1189         }
1190 
1191         if (!tzp || !tzp->tbp)
1192                 goto exit;
1193 
1194         list_for_each_entry(pos, &thermal_cdev_list, node) {
1195                 for (i = 0; i < tzp->num_tbps; i++) {
1196                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1197                                 continue;
1198                         if (tzp->tbp[i].match(tz, pos))
1199                                 continue;
1200                         tzp->tbp[i].cdev = pos;
1201                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1202                                tzp->tbp[i].binding_limits,
1203                                tzp->tbp[i].weight);
1204                 }
1205         }
1206 exit:
1207         mutex_unlock(&thermal_list_lock);
1208 }
1209 
1210 /**
1211  * thermal_zone_device_register() - register a new thermal zone device
1212  * @type:       the thermal zone device type
1213  * @trips:      the number of trip points the thermal zone support
1214  * @mask:       a bit string indicating the writeablility of trip points
1215  * @devdata:    private device data
1216  * @ops:        standard thermal zone device callbacks
1217  * @tzp:        thermal zone platform parameters
1218  * @passive_delay: number of milliseconds to wait between polls when
1219  *                 performing passive cooling
1220  * @polling_delay: number of milliseconds to wait between polls when checking
1221  *                 whether trip points have been crossed (0 for interrupt
1222  *                 driven systems)
1223  *
1224  * This interface function adds a new thermal zone device (sensor) to
1225  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1226  * thermal cooling devices registered at the same time.
1227  * thermal_zone_device_unregister() must be called when the device is no
1228  * longer needed. The passive cooling depends on the .get_trend() return value.
1229  *
1230  * Return: a pointer to the created struct thermal_zone_device or an
1231  * in case of error, an ERR_PTR. Caller must check return value with
1232  * IS_ERR*() helpers.
1233  */
1234 struct thermal_zone_device *
1235 thermal_zone_device_register(const char *type, int trips, int mask,
1236                              void *devdata, struct thermal_zone_device_ops *ops,
1237                              struct thermal_zone_params *tzp, int passive_delay,
1238                              int polling_delay)
1239 {
1240         struct thermal_zone_device *tz;
1241         enum thermal_trip_type trip_type;
1242         int trip_temp;
1243         int id;
1244         int result;
1245         int count;
1246         struct thermal_governor *governor;
1247 
1248         if (!type || strlen(type) == 0) {
1249                 pr_err("Error: No thermal zone type defined\n");
1250                 return ERR_PTR(-EINVAL);
1251         }
1252 
1253         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1254                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1255                        type, THERMAL_NAME_LENGTH);
1256                 return ERR_PTR(-EINVAL);
1257         }
1258 
1259         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1260                 pr_err("Error: Incorrect number of thermal trips\n");
1261                 return ERR_PTR(-EINVAL);
1262         }
1263 
1264         if (!ops) {
1265                 pr_err("Error: Thermal zone device ops not defined\n");
1266                 return ERR_PTR(-EINVAL);
1267         }
1268 
1269         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1270                 return ERR_PTR(-EINVAL);
1271 
1272         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1273         if (!tz)
1274                 return ERR_PTR(-ENOMEM);
1275 
1276         INIT_LIST_HEAD(&tz->thermal_instances);
1277         ida_init(&tz->ida);
1278         mutex_init(&tz->lock);
1279         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1280         if (id < 0) {
1281                 result = id;
1282                 goto free_tz;
1283         }
1284 
1285         tz->id = id;
1286         strlcpy(tz->type, type, sizeof(tz->type));
1287         tz->ops = ops;
1288         tz->tzp = tzp;
1289         tz->device.class = &thermal_class;
1290         tz->devdata = devdata;
1291         tz->trips = trips;
1292         tz->passive_delay = passive_delay;
1293         tz->polling_delay = polling_delay;
1294 
1295         /* sys I/F */
1296         /* Add nodes that are always present via .groups */
1297         result = thermal_zone_create_device_groups(tz, mask);
1298         if (result)
1299                 goto remove_id;
1300 
1301         /* A new thermal zone needs to be updated anyway. */
1302         atomic_set(&tz->need_update, 1);
1303 
1304         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1305         result = device_register(&tz->device);
1306         if (result)
1307                 goto release_device;
1308 
1309         for (count = 0; count < trips; count++) {
1310                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1311                         set_bit(count, &tz->trips_disabled);
1312                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1313                         set_bit(count, &tz->trips_disabled);
1314                 /* Check for bogus trip points */
1315                 if (trip_temp == 0)
1316                         set_bit(count, &tz->trips_disabled);
1317         }
1318 
1319         /* Update 'this' zone's governor information */
1320         mutex_lock(&thermal_governor_lock);
1321 
1322         if (tz->tzp)
1323                 governor = __find_governor(tz->tzp->governor_name);
1324         else
1325                 governor = def_governor;
1326 
1327         result = thermal_set_governor(tz, governor);
1328         if (result) {
1329                 mutex_unlock(&thermal_governor_lock);
1330                 goto unregister;
1331         }
1332 
1333         mutex_unlock(&thermal_governor_lock);
1334 
1335         if (!tz->tzp || !tz->tzp->no_hwmon) {
1336                 result = thermal_add_hwmon_sysfs(tz);
1337                 if (result)
1338                         goto unregister;
1339         }
1340 
1341         mutex_lock(&thermal_list_lock);
1342         list_add_tail(&tz->node, &thermal_tz_list);
1343         mutex_unlock(&thermal_list_lock);
1344 
1345         /* Bind cooling devices for this zone */
1346         bind_tz(tz);
1347 
1348         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1349 
1350         thermal_zone_device_reset(tz);
1351         /* Update the new thermal zone and mark it as already updated. */
1352         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1353                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1354 
1355         return tz;
1356 
1357 unregister:
1358         device_del(&tz->device);
1359 release_device:
1360         put_device(&tz->device);
1361         tz = NULL;
1362 remove_id:
1363         ida_simple_remove(&thermal_tz_ida, id);
1364 free_tz:
1365         kfree(tz);
1366         return ERR_PTR(result);
1367 }
1368 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1369 
1370 /**
1371  * thermal_device_unregister - removes the registered thermal zone device
1372  * @tz: the thermal zone device to remove
1373  */
1374 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1375 {
1376         int i;
1377         const struct thermal_zone_params *tzp;
1378         struct thermal_cooling_device *cdev;
1379         struct thermal_zone_device *pos = NULL;
1380 
1381         if (!tz)
1382                 return;
1383 
1384         tzp = tz->tzp;
1385 
1386         mutex_lock(&thermal_list_lock);
1387         list_for_each_entry(pos, &thermal_tz_list, node)
1388                 if (pos == tz)
1389                         break;
1390         if (pos != tz) {
1391                 /* thermal zone device not found */
1392                 mutex_unlock(&thermal_list_lock);
1393                 return;
1394         }
1395         list_del(&tz->node);
1396 
1397         /* Unbind all cdevs associated with 'this' thermal zone */
1398         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1399                 if (tz->ops->unbind) {
1400                         tz->ops->unbind(tz, cdev);
1401                         continue;
1402                 }
1403 
1404                 if (!tzp || !tzp->tbp)
1405                         break;
1406 
1407                 for (i = 0; i < tzp->num_tbps; i++) {
1408                         if (tzp->tbp[i].cdev == cdev) {
1409                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1410                                 tzp->tbp[i].cdev = NULL;
1411                         }
1412                 }
1413         }
1414 
1415         mutex_unlock(&thermal_list_lock);
1416 
1417         cancel_delayed_work_sync(&tz->poll_queue);
1418 
1419         thermal_set_governor(tz, NULL);
1420 
1421         thermal_remove_hwmon_sysfs(tz);
1422         ida_simple_remove(&thermal_tz_ida, tz->id);
1423         ida_destroy(&tz->ida);
1424         mutex_destroy(&tz->lock);
1425         device_unregister(&tz->device);
1426 }
1427 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1428 
1429 /**
1430  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1431  * @name: thermal zone name to fetch the temperature
1432  *
1433  * When only one zone is found with the passed name, returns a reference to it.
1434  *
1435  * Return: On success returns a reference to an unique thermal zone with
1436  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1437  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1438  */
1439 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1440 {
1441         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1442         unsigned int found = 0;
1443 
1444         if (!name)
1445                 goto exit;
1446 
1447         mutex_lock(&thermal_list_lock);
1448         list_for_each_entry(pos, &thermal_tz_list, node)
1449                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1450                         found++;
1451                         ref = pos;
1452                 }
1453         mutex_unlock(&thermal_list_lock);
1454 
1455         /* nothing has been found, thus an error code for it */
1456         if (found == 0)
1457                 ref = ERR_PTR(-ENODEV);
1458         else if (found > 1)
1459         /* Success only when an unique zone is found */
1460                 ref = ERR_PTR(-EEXIST);
1461 
1462 exit:
1463         return ref;
1464 }
1465 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1466 
1467 #ifdef CONFIG_NET
1468 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1469         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1470 };
1471 
1472 static struct genl_family thermal_event_genl_family __ro_after_init = {
1473         .module = THIS_MODULE,
1474         .name = THERMAL_GENL_FAMILY_NAME,
1475         .version = THERMAL_GENL_VERSION,
1476         .maxattr = THERMAL_GENL_ATTR_MAX,
1477         .mcgrps = thermal_event_mcgrps,
1478         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1479 };
1480 
1481 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1482                                    enum events event)
1483 {
1484         struct sk_buff *skb;
1485         struct nlattr *attr;
1486         struct thermal_genl_event *thermal_event;
1487         void *msg_header;
1488         int size;
1489         int result;
1490         static unsigned int thermal_event_seqnum;
1491 
1492         if (!tz)
1493                 return -EINVAL;
1494 
1495         /* allocate memory */
1496         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1497                nla_total_size(0);
1498 
1499         skb = genlmsg_new(size, GFP_ATOMIC);
1500         if (!skb)
1501                 return -ENOMEM;
1502 
1503         /* add the genetlink message header */
1504         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1505                                  &thermal_event_genl_family, 0,
1506                                  THERMAL_GENL_CMD_EVENT);
1507         if (!msg_header) {
1508                 nlmsg_free(skb);
1509                 return -ENOMEM;
1510         }
1511 
1512         /* fill the data */
1513         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1514                            sizeof(struct thermal_genl_event));
1515 
1516         if (!attr) {
1517                 nlmsg_free(skb);
1518                 return -EINVAL;
1519         }
1520 
1521         thermal_event = nla_data(attr);
1522         if (!thermal_event) {
1523                 nlmsg_free(skb);
1524                 return -EINVAL;
1525         }
1526 
1527         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1528 
1529         thermal_event->orig = tz->id;
1530         thermal_event->event = event;
1531 
1532         /* send multicast genetlink message */
1533         genlmsg_end(skb, msg_header);
1534 
1535         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1536                                    0, GFP_ATOMIC);
1537         if (result)
1538                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1539 
1540         return result;
1541 }
1542 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1543 
1544 static int __init genetlink_init(void)
1545 {
1546         return genl_register_family(&thermal_event_genl_family);
1547 }
1548 
1549 static void genetlink_exit(void)
1550 {
1551         genl_unregister_family(&thermal_event_genl_family);
1552 }
1553 #else /* !CONFIG_NET */
1554 static inline int genetlink_init(void) { return 0; }
1555 static inline void genetlink_exit(void) {}
1556 #endif /* !CONFIG_NET */
1557 
1558 static int thermal_pm_notify(struct notifier_block *nb,
1559                              unsigned long mode, void *_unused)
1560 {
1561         struct thermal_zone_device *tz;
1562         enum thermal_device_mode tz_mode;
1563 
1564         switch (mode) {
1565         case PM_HIBERNATION_PREPARE:
1566         case PM_RESTORE_PREPARE:
1567         case PM_SUSPEND_PREPARE:
1568                 atomic_set(&in_suspend, 1);
1569                 break;
1570         case PM_POST_HIBERNATION:
1571         case PM_POST_RESTORE:
1572         case PM_POST_SUSPEND:
1573                 atomic_set(&in_suspend, 0);
1574                 list_for_each_entry(tz, &thermal_tz_list, node) {
1575                         tz_mode = THERMAL_DEVICE_ENABLED;
1576                         if (tz->ops->get_mode)
1577                                 tz->ops->get_mode(tz, &tz_mode);
1578 
1579                         if (tz_mode == THERMAL_DEVICE_DISABLED)
1580                                 continue;
1581 
1582                         thermal_zone_device_init(tz);
1583                         thermal_zone_device_update(tz,
1584                                                    THERMAL_EVENT_UNSPECIFIED);
1585                 }
1586                 break;
1587         default:
1588                 break;
1589         }
1590         return 0;
1591 }
1592 
1593 static struct notifier_block thermal_pm_nb = {
1594         .notifier_call = thermal_pm_notify,
1595 };
1596 
1597 static int __init thermal_init(void)
1598 {
1599         int result;
1600 
1601         mutex_init(&poweroff_lock);
1602         result = thermal_register_governors();
1603         if (result)
1604                 goto error;
1605 
1606         result = class_register(&thermal_class);
1607         if (result)
1608                 goto unregister_governors;
1609 
1610         result = genetlink_init();
1611         if (result)
1612                 goto unregister_class;
1613 
1614         result = of_parse_thermal_zones();
1615         if (result)
1616                 goto exit_netlink;
1617 
1618         result = register_pm_notifier(&thermal_pm_nb);
1619         if (result)
1620                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1621                         result);
1622 
1623         return 0;
1624 
1625 exit_netlink:
1626         genetlink_exit();
1627 unregister_class:
1628         class_unregister(&thermal_class);
1629 unregister_governors:
1630         thermal_unregister_governors();
1631 error:
1632         ida_destroy(&thermal_tz_ida);
1633         ida_destroy(&thermal_cdev_ida);
1634         mutex_destroy(&thermal_list_lock);
1635         mutex_destroy(&thermal_governor_lock);
1636         mutex_destroy(&poweroff_lock);
1637         return result;
1638 }
1639 fs_initcall(thermal_init);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/thermal/thermal_core.c

DEFINITIONS
