1 // SPDX-License-Identifier: GPL-2.0
3 * thermal.c - Generic Thermal Management Sysfs support.
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>
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/slab.h>
16 #include <linux/kdev_t.h>
17 #include <linux/idr.h>
18 #include <linux/thermal.h>
19 #include <linux/reboot.h>
20 #include <linux/string.h>
22 #include <linux/suspend.h>
24 #define CREATE_TRACE_POINTS
25 #include <trace/events/thermal.h>
27 #include "thermal_core.h"
28 #include "thermal_hwmon.h"
30 static DEFINE_IDA(thermal_tz_ida);
31 static DEFINE_IDA(thermal_cdev_ida);
33 static LIST_HEAD(thermal_tz_list);
34 static LIST_HEAD(thermal_cdev_list);
35 static LIST_HEAD(thermal_governor_list);
37 static DEFINE_MUTEX(thermal_list_lock);
38 static DEFINE_MUTEX(thermal_governor_lock);
39 static DEFINE_MUTEX(poweroff_lock);
41 static atomic_t in_suspend;
42 static bool power_off_triggered;
44 static struct thermal_governor *def_governor;
47 * Governor section: set of functions to handle thermal governors
49 * Functions to help in the life cycle of thermal governors within
50 * the thermal core and by the thermal governor code.
53 static struct thermal_governor *__find_governor(const char *name)
55 struct thermal_governor *pos;
57 if (!name || !name[0])
60 list_for_each_entry(pos, &thermal_governor_list, governor_list)
61 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
68 * bind_previous_governor() - bind the previous governor of the thermal zone
69 * @tz: a valid pointer to a struct thermal_zone_device
70 * @failed_gov_name: the name of the governor that failed to register
72 * Register the previous governor of the thermal zone after a new
73 * governor has failed to be bound.
75 static void bind_previous_governor(struct thermal_zone_device *tz,
76 const char *failed_gov_name)
78 if (tz->governor && tz->governor->bind_to_tz) {
79 if (tz->governor->bind_to_tz(tz)) {
81 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
82 failed_gov_name, tz->governor->name, tz->type);
89 * thermal_set_governor() - Switch to another governor
90 * @tz: a valid pointer to a struct thermal_zone_device
91 * @new_gov: pointer to the new governor
93 * Change the governor of thermal zone @tz.
95 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
97 static int thermal_set_governor(struct thermal_zone_device *tz,
98 struct thermal_governor *new_gov)
102 if (tz->governor && tz->governor->unbind_from_tz)
103 tz->governor->unbind_from_tz(tz);
105 if (new_gov && new_gov->bind_to_tz) {
106 ret = new_gov->bind_to_tz(tz);
108 bind_previous_governor(tz, new_gov->name);
114 tz->governor = new_gov;
119 int thermal_register_governor(struct thermal_governor *governor)
123 struct thermal_zone_device *pos;
128 mutex_lock(&thermal_governor_lock);
131 if (!__find_governor(governor->name)) {
135 list_add(&governor->governor_list, &thermal_governor_list);
136 match_default = !strncmp(governor->name,
137 DEFAULT_THERMAL_GOVERNOR,
138 THERMAL_NAME_LENGTH);
140 if (!def_governor && match_default)
141 def_governor = governor;
144 mutex_lock(&thermal_list_lock);
146 list_for_each_entry(pos, &thermal_tz_list, node) {
148 * only thermal zones with specified tz->tzp->governor_name
149 * may run with tz->govenor unset
154 name = pos->tzp->governor_name;
156 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
159 ret = thermal_set_governor(pos, governor);
161 dev_err(&pos->device,
162 "Failed to set governor %s for thermal zone %s: %d\n",
163 governor->name, pos->type, ret);
167 mutex_unlock(&thermal_list_lock);
168 mutex_unlock(&thermal_governor_lock);
173 void thermal_unregister_governor(struct thermal_governor *governor)
175 struct thermal_zone_device *pos;
180 mutex_lock(&thermal_governor_lock);
182 if (!__find_governor(governor->name))
185 mutex_lock(&thermal_list_lock);
187 list_for_each_entry(pos, &thermal_tz_list, node) {
188 if (!strncasecmp(pos->governor->name, governor->name,
189 THERMAL_NAME_LENGTH))
190 thermal_set_governor(pos, NULL);
193 mutex_unlock(&thermal_list_lock);
194 list_del(&governor->governor_list);
196 mutex_unlock(&thermal_governor_lock);
199 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
202 struct thermal_governor *gov;
205 mutex_lock(&thermal_governor_lock);
206 mutex_lock(&tz->lock);
208 gov = __find_governor(strim(policy));
212 ret = thermal_set_governor(tz, gov);
215 mutex_unlock(&tz->lock);
216 mutex_unlock(&thermal_governor_lock);
221 int thermal_build_list_of_policies(char *buf)
223 struct thermal_governor *pos;
225 ssize_t size = PAGE_SIZE;
227 mutex_lock(&thermal_governor_lock);
229 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
230 size = PAGE_SIZE - count;
231 count += scnprintf(buf + count, size, "%s ", pos->name);
233 count += scnprintf(buf + count, size, "\n");
235 mutex_unlock(&thermal_governor_lock);
240 static void __init thermal_unregister_governors(void)
242 struct thermal_governor **governor;
244 for_each_governor_table(governor)
245 thermal_unregister_governor(*governor);
248 static int __init thermal_register_governors(void)
251 struct thermal_governor **governor;
253 for_each_governor_table(governor) {
254 ret = thermal_register_governor(*governor);
256 pr_err("Failed to register governor: '%s'",
261 pr_info("Registered thermal governor '%s'",
266 struct thermal_governor **gov;
268 for_each_governor_table(gov) {
271 thermal_unregister_governor(*gov);
279 * Zone update section: main control loop applied to each zone while monitoring
281 * in polling mode. The monitoring is done using a workqueue.
282 * Same update may be done on a zone by calling thermal_zone_device_update().
285 * - Non-critical trips will invoke the governor responsible for that zone;
286 * - Hot trips will produce a notification to userspace;
287 * - Critical trip point will cause a system shutdown.
289 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
293 mod_delayed_work(system_freezable_power_efficient_wq,
295 round_jiffies(msecs_to_jiffies(delay)));
297 mod_delayed_work(system_freezable_power_efficient_wq,
299 msecs_to_jiffies(delay));
301 cancel_delayed_work(&tz->poll_queue);
304 static inline bool should_stop_polling(struct thermal_zone_device *tz)
306 return !thermal_zone_device_is_enabled(tz);
309 static void monitor_thermal_zone(struct thermal_zone_device *tz)
313 stop = should_stop_polling(tz);
315 mutex_lock(&tz->lock);
317 if (!stop && tz->passive)
318 thermal_zone_device_set_polling(tz, tz->passive_delay);
319 else if (!stop && tz->polling_delay)
320 thermal_zone_device_set_polling(tz, tz->polling_delay);
322 thermal_zone_device_set_polling(tz, 0);
324 mutex_unlock(&tz->lock);
327 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
329 tz->governor ? tz->governor->throttle(tz, trip) :
330 def_governor->throttle(tz, trip);
334 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
335 * @work: work_struct associated with the emergency poweroff function
337 * This function is called in very critical situations to force
338 * a kernel poweroff after a configurable timeout value.
340 static void thermal_emergency_poweroff_func(struct work_struct *work)
343 * We have reached here after the emergency thermal shutdown
344 * Waiting period has expired. This means orderly_poweroff has
345 * not been able to shut off the system for some reason.
346 * Try to shut down the system immediately using kernel_power_off
349 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
353 * Worst of the worst case trigger emergency restart
355 WARN(1, "Attempting emergency_restart: Temperature too high\n");
359 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
360 thermal_emergency_poweroff_func);
363 * thermal_emergency_poweroff - Trigger an emergency system poweroff
365 * This may be called from any critical situation to trigger a system shutdown
366 * after a known period of time. By default this is not scheduled.
368 static void thermal_emergency_poweroff(void)
370 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
372 * poweroff_delay_ms must be a carefully profiled positive value.
373 * Its a must for thermal_emergency_poweroff_work to be scheduled
375 if (poweroff_delay_ms <= 0)
377 schedule_delayed_work(&thermal_emergency_poweroff_work,
378 msecs_to_jiffies(poweroff_delay_ms));
381 static void handle_critical_trips(struct thermal_zone_device *tz,
382 int trip, enum thermal_trip_type trip_type)
386 tz->ops->get_trip_temp(tz, trip, &trip_temp);
388 /* If we have not crossed the trip_temp, we do not care. */
389 if (trip_temp <= 0 || tz->temperature < trip_temp)
392 trace_thermal_zone_trip(tz, trip, trip_type);
395 tz->ops->notify(tz, trip, trip_type);
397 if (trip_type == THERMAL_TRIP_CRITICAL) {
398 dev_emerg(&tz->device,
399 "critical temperature reached (%d C), shutting down\n",
400 tz->temperature / 1000);
401 mutex_lock(&poweroff_lock);
402 if (!power_off_triggered) {
404 * Queue a backup emergency shutdown in the event of
405 * orderly_poweroff failure
407 thermal_emergency_poweroff();
408 orderly_poweroff(true);
409 power_off_triggered = true;
411 mutex_unlock(&poweroff_lock);
415 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
417 enum thermal_trip_type type;
419 /* Ignore disabled trip points */
420 if (test_bit(trip, &tz->trips_disabled))
423 tz->ops->get_trip_type(tz, trip, &type);
425 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
426 handle_critical_trips(tz, trip, type);
428 handle_non_critical_trips(tz, trip);
430 * Alright, we handled this trip successfully.
431 * So, start monitoring again.
433 monitor_thermal_zone(tz);
436 static void update_temperature(struct thermal_zone_device *tz)
440 ret = thermal_zone_get_temp(tz, &temp);
443 dev_warn(&tz->device,
444 "failed to read out thermal zone (%d)\n",
449 mutex_lock(&tz->lock);
450 tz->last_temperature = tz->temperature;
451 tz->temperature = temp;
452 mutex_unlock(&tz->lock);
454 trace_thermal_temperature(tz);
457 static void thermal_zone_device_init(struct thermal_zone_device *tz)
459 struct thermal_instance *pos;
460 tz->temperature = THERMAL_TEMP_INVALID;
461 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
462 pos->initialized = false;
465 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
468 thermal_zone_device_init(tz);
471 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
472 enum thermal_device_mode mode)
476 mutex_lock(&tz->lock);
478 /* do nothing if mode isn't changing */
479 if (mode == tz->mode) {
480 mutex_unlock(&tz->lock);
485 if (tz->ops->change_mode)
486 ret = tz->ops->change_mode(tz, mode);
491 mutex_unlock(&tz->lock);
493 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
498 int thermal_zone_device_enable(struct thermal_zone_device *tz)
500 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
502 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
504 int thermal_zone_device_disable(struct thermal_zone_device *tz)
506 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
508 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
510 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
512 enum thermal_device_mode mode;
514 mutex_lock(&tz->lock);
518 mutex_unlock(&tz->lock);
520 return mode == THERMAL_DEVICE_ENABLED;
523 void thermal_zone_device_update(struct thermal_zone_device *tz,
524 enum thermal_notify_event event)
528 if (should_stop_polling(tz))
531 if (atomic_read(&in_suspend))
534 if (!tz->ops->get_temp)
537 update_temperature(tz);
539 thermal_zone_set_trips(tz);
541 tz->notify_event = event;
543 for (count = 0; count < tz->trips; count++)
544 handle_thermal_trip(tz, count);
546 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
549 * thermal_notify_framework - Sensor drivers use this API to notify framework
550 * @tz: thermal zone device
551 * @trip: indicates which trip point has been crossed
553 * This function handles the trip events from sensor drivers. It starts
554 * throttling the cooling devices according to the policy configured.
555 * For CRITICAL and HOT trip points, this notifies the respective drivers,
556 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
557 * The throttling policy is based on the configured platform data; if no
558 * platform data is provided, this uses the step_wise throttling policy.
560 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
562 handle_thermal_trip(tz, trip);
564 EXPORT_SYMBOL_GPL(thermal_notify_framework);
566 static void thermal_zone_device_check(struct work_struct *work)
568 struct thermal_zone_device *tz = container_of(work, struct
571 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
575 * Power actor section: interface to power actors to estimate power
577 * Set of functions used to interact to cooling devices that know
578 * how to estimate their devices power consumption.
582 * power_actor_get_max_power() - get the maximum power that a cdev can consume
583 * @cdev: pointer to &thermal_cooling_device
584 * @tz: a valid thermal zone device pointer
585 * @max_power: pointer in which to store the maximum power
587 * Calculate the maximum power consumption in milliwats that the
588 * cooling device can currently consume and store it in @max_power.
590 * Return: 0 on success, -EINVAL if @cdev doesn't support the
591 * power_actor API or -E* on other error.
593 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
594 struct thermal_zone_device *tz, u32 *max_power)
596 if (!cdev_is_power_actor(cdev))
599 return cdev->ops->state2power(cdev, tz, 0, max_power);
603 * power_actor_get_min_power() - get the mainimum power that a cdev can consume
604 * @cdev: pointer to &thermal_cooling_device
605 * @tz: a valid thermal zone device pointer
606 * @min_power: pointer in which to store the minimum power
608 * Calculate the minimum power consumption in milliwatts that the
609 * cooling device can currently consume and store it in @min_power.
611 * Return: 0 on success, -EINVAL if @cdev doesn't support the
612 * power_actor API or -E* on other error.
614 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
615 struct thermal_zone_device *tz, u32 *min_power)
617 unsigned long max_state;
620 if (!cdev_is_power_actor(cdev))
623 ret = cdev->ops->get_max_state(cdev, &max_state);
627 return cdev->ops->state2power(cdev, tz, max_state, min_power);
631 * power_actor_set_power() - limit the maximum power a cooling device consumes
632 * @cdev: pointer to &thermal_cooling_device
633 * @instance: thermal instance to update
634 * @power: the power in milliwatts
636 * Set the cooling device to consume at most @power milliwatts. The limit is
637 * expected to be a cap at the maximum power consumption.
639 * Return: 0 on success, -EINVAL if the cooling device does not
640 * implement the power actor API or -E* for other failures.
642 int power_actor_set_power(struct thermal_cooling_device *cdev,
643 struct thermal_instance *instance, u32 power)
648 if (!cdev_is_power_actor(cdev))
651 ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
655 instance->target = state;
656 mutex_lock(&cdev->lock);
657 cdev->updated = false;
658 mutex_unlock(&cdev->lock);
659 thermal_cdev_update(cdev);
664 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
665 const char *cdev_type, size_t size)
667 struct thermal_cooling_device *cdev = NULL;
669 mutex_lock(&thermal_list_lock);
670 list_for_each_entry(cdev, &thermal_cdev_list, node) {
671 /* skip non matching cdevs */
672 if (strncmp(cdev_type, cdev->type, size))
675 /* re binding the exception matching the type pattern */
676 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
679 THERMAL_WEIGHT_DEFAULT);
681 mutex_unlock(&thermal_list_lock);
684 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
687 struct thermal_governor *gov;
690 mutex_lock(&thermal_governor_lock);
691 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
696 mutex_unlock(&thermal_governor_lock);
701 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
704 struct thermal_cooling_device *cdev;
707 mutex_lock(&thermal_list_lock);
708 list_for_each_entry(cdev, &thermal_cdev_list, node) {
709 ret = cb(cdev, data);
713 mutex_unlock(&thermal_list_lock);
718 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
721 struct thermal_zone_device *tz;
724 mutex_lock(&thermal_list_lock);
725 list_for_each_entry(tz, &thermal_tz_list, node) {
730 mutex_unlock(&thermal_list_lock);
735 struct thermal_zone_device *thermal_zone_get_by_id(int id)
737 struct thermal_zone_device *tz = NULL;
739 mutex_lock(&thermal_list_lock);
740 list_for_each_entry(tz, &thermal_tz_list, node) {
744 mutex_unlock(&thermal_list_lock);
749 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
750 const char *cdev_type, size_t size)
752 struct thermal_cooling_device *cdev = NULL;
754 mutex_lock(&thermal_list_lock);
755 list_for_each_entry(cdev, &thermal_cdev_list, node) {
756 /* skip non matching cdevs */
757 if (strncmp(cdev_type, cdev->type, size))
759 /* unbinding the exception matching the type pattern */
760 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
763 mutex_unlock(&thermal_list_lock);
767 * Device management section: cooling devices, zones devices, and binding
769 * Set of functions provided by the thermal core for:
770 * - cooling devices lifecycle: registration, unregistration,
771 * binding, and unbinding.
772 * - thermal zone devices lifecycle: registration, unregistration,
773 * binding, and unbinding.
777 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
778 * @tz: pointer to struct thermal_zone_device
779 * @trip: indicates which trip point the cooling devices is
780 * associated with in this thermal zone.
781 * @cdev: pointer to struct thermal_cooling_device
782 * @upper: the Maximum cooling state for this trip point.
783 * THERMAL_NO_LIMIT means no upper limit,
784 * and the cooling device can be in max_state.
785 * @lower: the Minimum cooling state can be used for this trip point.
786 * THERMAL_NO_LIMIT means no lower limit,
787 * and the cooling device can be in cooling state 0.
788 * @weight: The weight of the cooling device to be bound to the
789 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
792 * This interface function bind a thermal cooling device to the certain trip
793 * point of a thermal zone device.
794 * This function is usually called in the thermal zone device .bind callback.
796 * Return: 0 on success, the proper error value otherwise.
798 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
800 struct thermal_cooling_device *cdev,
801 unsigned long upper, unsigned long lower,
804 struct thermal_instance *dev;
805 struct thermal_instance *pos;
806 struct thermal_zone_device *pos1;
807 struct thermal_cooling_device *pos2;
808 unsigned long max_state;
811 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
814 list_for_each_entry(pos1, &thermal_tz_list, node) {
818 list_for_each_entry(pos2, &thermal_cdev_list, node) {
823 if (tz != pos1 || cdev != pos2)
826 ret = cdev->ops->get_max_state(cdev, &max_state);
830 /* lower default 0, upper default max_state */
831 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
832 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
834 if (lower > upper || upper > max_state)
837 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
845 dev->target = THERMAL_NO_TARGET;
846 dev->weight = weight;
848 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
853 sprintf(dev->name, "cdev%d", dev->id);
855 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
859 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
860 sysfs_attr_init(&dev->attr.attr);
861 dev->attr.attr.name = dev->attr_name;
862 dev->attr.attr.mode = 0444;
863 dev->attr.show = trip_point_show;
864 result = device_create_file(&tz->device, &dev->attr);
866 goto remove_symbol_link;
868 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
869 sysfs_attr_init(&dev->weight_attr.attr);
870 dev->weight_attr.attr.name = dev->weight_attr_name;
871 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
872 dev->weight_attr.show = weight_show;
873 dev->weight_attr.store = weight_store;
874 result = device_create_file(&tz->device, &dev->weight_attr);
876 goto remove_trip_file;
878 mutex_lock(&tz->lock);
879 mutex_lock(&cdev->lock);
880 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
881 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
886 list_add_tail(&dev->tz_node, &tz->thermal_instances);
887 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
888 atomic_set(&tz->need_update, 1);
890 mutex_unlock(&cdev->lock);
891 mutex_unlock(&tz->lock);
896 device_remove_file(&tz->device, &dev->weight_attr);
898 device_remove_file(&tz->device, &dev->attr);
900 sysfs_remove_link(&tz->device.kobj, dev->name);
902 ida_simple_remove(&tz->ida, dev->id);
907 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
910 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
912 * @tz: pointer to a struct thermal_zone_device.
913 * @trip: indicates which trip point the cooling devices is
914 * associated with in this thermal zone.
915 * @cdev: pointer to a struct thermal_cooling_device.
917 * This interface function unbind a thermal cooling device from the certain
918 * trip point of a thermal zone device.
919 * This function is usually called in the thermal zone device .unbind callback.
921 * Return: 0 on success, the proper error value otherwise.
923 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
925 struct thermal_cooling_device *cdev)
927 struct thermal_instance *pos, *next;
929 mutex_lock(&tz->lock);
930 mutex_lock(&cdev->lock);
931 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
932 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
933 list_del(&pos->tz_node);
934 list_del(&pos->cdev_node);
935 mutex_unlock(&cdev->lock);
936 mutex_unlock(&tz->lock);
940 mutex_unlock(&cdev->lock);
941 mutex_unlock(&tz->lock);
946 device_remove_file(&tz->device, &pos->weight_attr);
947 device_remove_file(&tz->device, &pos->attr);
948 sysfs_remove_link(&tz->device.kobj, pos->name);
949 ida_simple_remove(&tz->ida, pos->id);
953 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
955 static void thermal_release(struct device *dev)
957 struct thermal_zone_device *tz;
958 struct thermal_cooling_device *cdev;
960 if (!strncmp(dev_name(dev), "thermal_zone",
961 sizeof("thermal_zone") - 1)) {
962 tz = to_thermal_zone(dev);
963 thermal_zone_destroy_device_groups(tz);
965 } else if (!strncmp(dev_name(dev), "cooling_device",
966 sizeof("cooling_device") - 1)) {
967 cdev = to_cooling_device(dev);
972 static struct class thermal_class = {
974 .dev_release = thermal_release,
978 void print_bind_err_msg(struct thermal_zone_device *tz,
979 struct thermal_cooling_device *cdev, int ret)
981 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
982 tz->type, cdev->type, ret);
985 static void __bind(struct thermal_zone_device *tz, int mask,
986 struct thermal_cooling_device *cdev,
987 unsigned long *limits,
992 for (i = 0; i < tz->trips; i++) {
993 if (mask & (1 << i)) {
994 unsigned long upper, lower;
996 upper = THERMAL_NO_LIMIT;
997 lower = THERMAL_NO_LIMIT;
999 lower = limits[i * 2];
1000 upper = limits[i * 2 + 1];
1002 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
1006 print_bind_err_msg(tz, cdev, ret);
1011 static void bind_cdev(struct thermal_cooling_device *cdev)
1014 const struct thermal_zone_params *tzp;
1015 struct thermal_zone_device *pos = NULL;
1017 mutex_lock(&thermal_list_lock);
1019 list_for_each_entry(pos, &thermal_tz_list, node) {
1020 if (!pos->tzp && !pos->ops->bind)
1023 if (pos->ops->bind) {
1024 ret = pos->ops->bind(pos, cdev);
1026 print_bind_err_msg(pos, cdev, ret);
1031 if (!tzp || !tzp->tbp)
1034 for (i = 0; i < tzp->num_tbps; i++) {
1035 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1037 if (tzp->tbp[i].match(pos, cdev))
1039 tzp->tbp[i].cdev = cdev;
1040 __bind(pos, tzp->tbp[i].trip_mask, cdev,
1041 tzp->tbp[i].binding_limits,
1042 tzp->tbp[i].weight);
1046 mutex_unlock(&thermal_list_lock);
1050 * __thermal_cooling_device_register() - register a new thermal cooling device
1051 * @np: a pointer to a device tree node.
1052 * @type: the thermal cooling device type.
1053 * @devdata: device private data.
1054 * @ops: standard thermal cooling devices callbacks.
1056 * This interface function adds a new thermal cooling device (fan/processor/...)
1057 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1058 * to all the thermal zone devices registered at the same time.
1059 * It also gives the opportunity to link the cooling device to a device tree
1060 * node, so that it can be bound to a thermal zone created out of device tree.
1062 * Return: a pointer to the created struct thermal_cooling_device or an
1063 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1065 static struct thermal_cooling_device *
1066 __thermal_cooling_device_register(struct device_node *np,
1067 const char *type, void *devdata,
1068 const struct thermal_cooling_device_ops *ops)
1070 struct thermal_cooling_device *cdev;
1071 struct thermal_zone_device *pos = NULL;
1074 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1075 return ERR_PTR(-EINVAL);
1077 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1078 !ops->set_cur_state)
1079 return ERR_PTR(-EINVAL);
1081 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1083 return ERR_PTR(-ENOMEM);
1085 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1088 return ERR_PTR(result);
1092 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1093 mutex_init(&cdev->lock);
1094 INIT_LIST_HEAD(&cdev->thermal_instances);
1097 cdev->updated = false;
1098 cdev->device.class = &thermal_class;
1099 cdev->devdata = devdata;
1100 thermal_cooling_device_setup_sysfs(cdev);
1101 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1102 result = device_register(&cdev->device);
1104 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1105 put_device(&cdev->device);
1106 return ERR_PTR(result);
1109 /* Add 'this' new cdev to the global cdev list */
1110 mutex_lock(&thermal_list_lock);
1111 list_add(&cdev->node, &thermal_cdev_list);
1112 mutex_unlock(&thermal_list_lock);
1114 /* Update binding information for 'this' new cdev */
1117 mutex_lock(&thermal_list_lock);
1118 list_for_each_entry(pos, &thermal_tz_list, node)
1119 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1120 thermal_zone_device_update(pos,
1121 THERMAL_EVENT_UNSPECIFIED);
1122 mutex_unlock(&thermal_list_lock);
1128 * thermal_cooling_device_register() - register a new thermal cooling device
1129 * @type: the thermal cooling device type.
1130 * @devdata: device private data.
1131 * @ops: standard thermal cooling devices callbacks.
1133 * This interface function adds a new thermal cooling device (fan/processor/...)
1134 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1135 * to all the thermal zone devices registered at the same time.
1137 * Return: a pointer to the created struct thermal_cooling_device or an
1138 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1140 struct thermal_cooling_device *
1141 thermal_cooling_device_register(const char *type, void *devdata,
1142 const struct thermal_cooling_device_ops *ops)
1144 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1146 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1149 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1150 * @np: a pointer to a device tree node.
1151 * @type: the thermal cooling device type.
1152 * @devdata: device private data.
1153 * @ops: standard thermal cooling devices callbacks.
1155 * This function will register a cooling device with device tree node reference.
1156 * This interface function adds a new thermal cooling device (fan/processor/...)
1157 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1158 * to all the thermal zone devices registered at the same time.
1160 * Return: a pointer to the created struct thermal_cooling_device or an
1161 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1163 struct thermal_cooling_device *
1164 thermal_of_cooling_device_register(struct device_node *np,
1165 const char *type, void *devdata,
1166 const struct thermal_cooling_device_ops *ops)
1168 return __thermal_cooling_device_register(np, type, devdata, ops);
1170 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1172 static void thermal_cooling_device_release(struct device *dev, void *res)
1174 thermal_cooling_device_unregister(
1175 *(struct thermal_cooling_device **)res);
1179 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1181 * @dev: a valid struct device pointer of a sensor device.
1182 * @np: a pointer to a device tree node.
1183 * @type: the thermal cooling device type.
1184 * @devdata: device private data.
1185 * @ops: standard thermal cooling devices callbacks.
1187 * This function will register a cooling device with device tree node reference.
1188 * This interface function adds a new thermal cooling device (fan/processor/...)
1189 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1190 * to all the thermal zone devices registered at the same time.
1192 * Return: a pointer to the created struct thermal_cooling_device or an
1193 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1195 struct thermal_cooling_device *
1196 devm_thermal_of_cooling_device_register(struct device *dev,
1197 struct device_node *np,
1198 char *type, void *devdata,
1199 const struct thermal_cooling_device_ops *ops)
1201 struct thermal_cooling_device **ptr, *tcd;
1203 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1206 return ERR_PTR(-ENOMEM);
1208 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1215 devres_add(dev, ptr);
1219 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1221 static void __unbind(struct thermal_zone_device *tz, int mask,
1222 struct thermal_cooling_device *cdev)
1226 for (i = 0; i < tz->trips; i++)
1227 if (mask & (1 << i))
1228 thermal_zone_unbind_cooling_device(tz, i, cdev);
1232 * thermal_cooling_device_unregister - removes a thermal cooling device
1233 * @cdev: the thermal cooling device to remove.
1235 * thermal_cooling_device_unregister() must be called when a registered
1236 * thermal cooling device is no longer needed.
1238 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1241 const struct thermal_zone_params *tzp;
1242 struct thermal_zone_device *tz;
1243 struct thermal_cooling_device *pos = NULL;
1248 mutex_lock(&thermal_list_lock);
1249 list_for_each_entry(pos, &thermal_cdev_list, node)
1253 /* thermal cooling device not found */
1254 mutex_unlock(&thermal_list_lock);
1257 list_del(&cdev->node);
1259 /* Unbind all thermal zones associated with 'this' cdev */
1260 list_for_each_entry(tz, &thermal_tz_list, node) {
1261 if (tz->ops->unbind) {
1262 tz->ops->unbind(tz, cdev);
1266 if (!tz->tzp || !tz->tzp->tbp)
1270 for (i = 0; i < tzp->num_tbps; i++) {
1271 if (tzp->tbp[i].cdev == cdev) {
1272 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1273 tzp->tbp[i].cdev = NULL;
1278 mutex_unlock(&thermal_list_lock);
1280 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1281 device_del(&cdev->device);
1282 thermal_cooling_device_destroy_sysfs(cdev);
1283 put_device(&cdev->device);
1285 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1287 static void bind_tz(struct thermal_zone_device *tz)
1290 struct thermal_cooling_device *pos = NULL;
1291 const struct thermal_zone_params *tzp = tz->tzp;
1293 if (!tzp && !tz->ops->bind)
1296 mutex_lock(&thermal_list_lock);
1298 /* If there is ops->bind, try to use ops->bind */
1299 if (tz->ops->bind) {
1300 list_for_each_entry(pos, &thermal_cdev_list, node) {
1301 ret = tz->ops->bind(tz, pos);
1303 print_bind_err_msg(tz, pos, ret);
1308 if (!tzp || !tzp->tbp)
1311 list_for_each_entry(pos, &thermal_cdev_list, node) {
1312 for (i = 0; i < tzp->num_tbps; i++) {
1313 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1315 if (tzp->tbp[i].match(tz, pos))
1317 tzp->tbp[i].cdev = pos;
1318 __bind(tz, tzp->tbp[i].trip_mask, pos,
1319 tzp->tbp[i].binding_limits,
1320 tzp->tbp[i].weight);
1324 mutex_unlock(&thermal_list_lock);
1328 * thermal_zone_device_register() - register a new thermal zone device
1329 * @type: the thermal zone device type
1330 * @trips: the number of trip points the thermal zone support
1331 * @mask: a bit string indicating the writeablility of trip points
1332 * @devdata: private device data
1333 * @ops: standard thermal zone device callbacks
1334 * @tzp: thermal zone platform parameters
1335 * @passive_delay: number of milliseconds to wait between polls when
1336 * performing passive cooling
1337 * @polling_delay: number of milliseconds to wait between polls when checking
1338 * whether trip points have been crossed (0 for interrupt
1341 * This interface function adds a new thermal zone device (sensor) to
1342 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1343 * thermal cooling devices registered at the same time.
1344 * thermal_zone_device_unregister() must be called when the device is no
1345 * longer needed. The passive cooling depends on the .get_trend() return value.
1347 * Return: a pointer to the created struct thermal_zone_device or an
1348 * in case of error, an ERR_PTR. Caller must check return value with
1349 * IS_ERR*() helpers.
1351 struct thermal_zone_device *
1352 thermal_zone_device_register(const char *type, int trips, int mask,
1353 void *devdata, struct thermal_zone_device_ops *ops,
1354 struct thermal_zone_params *tzp, int passive_delay,
1357 struct thermal_zone_device *tz;
1358 enum thermal_trip_type trip_type;
1363 struct thermal_governor *governor;
1365 if (!type || strlen(type) == 0) {
1366 pr_err("Error: No thermal zone type defined\n");
1367 return ERR_PTR(-EINVAL);
1370 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1371 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1372 type, THERMAL_NAME_LENGTH);
1373 return ERR_PTR(-EINVAL);
1376 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1377 pr_err("Error: Incorrect number of thermal trips\n");
1378 return ERR_PTR(-EINVAL);
1382 pr_err("Error: Thermal zone device ops not defined\n");
1383 return ERR_PTR(-EINVAL);
1386 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1387 return ERR_PTR(-EINVAL);
1389 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1391 return ERR_PTR(-ENOMEM);
1393 INIT_LIST_HEAD(&tz->thermal_instances);
1395 mutex_init(&tz->lock);
1396 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1403 strlcpy(tz->type, type, sizeof(tz->type));
1406 tz->device.class = &thermal_class;
1407 tz->devdata = devdata;
1409 tz->passive_delay = passive_delay;
1410 tz->polling_delay = polling_delay;
1413 /* Add nodes that are always present via .groups */
1414 result = thermal_zone_create_device_groups(tz, mask);
1418 /* A new thermal zone needs to be updated anyway. */
1419 atomic_set(&tz->need_update, 1);
1421 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1422 result = device_register(&tz->device);
1424 goto release_device;
1426 for (count = 0; count < trips; count++) {
1427 if (tz->ops->get_trip_type(tz, count, &trip_type))
1428 set_bit(count, &tz->trips_disabled);
1429 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1430 set_bit(count, &tz->trips_disabled);
1431 /* Check for bogus trip points */
1433 set_bit(count, &tz->trips_disabled);
1436 /* Update 'this' zone's governor information */
1437 mutex_lock(&thermal_governor_lock);
1440 governor = __find_governor(tz->tzp->governor_name);
1442 governor = def_governor;
1444 result = thermal_set_governor(tz, governor);
1446 mutex_unlock(&thermal_governor_lock);
1450 mutex_unlock(&thermal_governor_lock);
1452 if (!tz->tzp || !tz->tzp->no_hwmon) {
1453 result = thermal_add_hwmon_sysfs(tz);
1458 mutex_lock(&thermal_list_lock);
1459 list_add_tail(&tz->node, &thermal_tz_list);
1460 mutex_unlock(&thermal_list_lock);
1462 /* Bind cooling devices for this zone */
1465 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1467 thermal_zone_device_reset(tz);
1468 /* Update the new thermal zone and mark it as already updated. */
1469 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1470 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1475 device_del(&tz->device);
1477 put_device(&tz->device);
1480 ida_simple_remove(&thermal_tz_ida, id);
1483 return ERR_PTR(result);
1485 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1488 * thermal_device_unregister - removes the registered thermal zone device
1489 * @tz: the thermal zone device to remove
1491 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1494 const struct thermal_zone_params *tzp;
1495 struct thermal_cooling_device *cdev;
1496 struct thermal_zone_device *pos = NULL;
1503 mutex_lock(&thermal_list_lock);
1504 list_for_each_entry(pos, &thermal_tz_list, node)
1508 /* thermal zone device not found */
1509 mutex_unlock(&thermal_list_lock);
1512 list_del(&tz->node);
1514 /* Unbind all cdevs associated with 'this' thermal zone */
1515 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1516 if (tz->ops->unbind) {
1517 tz->ops->unbind(tz, cdev);
1521 if (!tzp || !tzp->tbp)
1524 for (i = 0; i < tzp->num_tbps; i++) {
1525 if (tzp->tbp[i].cdev == cdev) {
1526 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1527 tzp->tbp[i].cdev = NULL;
1532 mutex_unlock(&thermal_list_lock);
1534 cancel_delayed_work_sync(&tz->poll_queue);
1536 thermal_set_governor(tz, NULL);
1538 thermal_remove_hwmon_sysfs(tz);
1539 ida_simple_remove(&thermal_tz_ida, tz->id);
1540 ida_destroy(&tz->ida);
1541 mutex_destroy(&tz->lock);
1542 device_unregister(&tz->device);
1544 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1547 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1548 * @name: thermal zone name to fetch the temperature
1550 * When only one zone is found with the passed name, returns a reference to it.
1552 * Return: On success returns a reference to an unique thermal zone with
1553 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1554 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1556 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1558 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1559 unsigned int found = 0;
1564 mutex_lock(&thermal_list_lock);
1565 list_for_each_entry(pos, &thermal_tz_list, node)
1566 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1570 mutex_unlock(&thermal_list_lock);
1572 /* nothing has been found, thus an error code for it */
1574 ref = ERR_PTR(-ENODEV);
1576 /* Success only when an unique zone is found */
1577 ref = ERR_PTR(-EEXIST);
1582 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1584 static int thermal_pm_notify(struct notifier_block *nb,
1585 unsigned long mode, void *_unused)
1587 struct thermal_zone_device *tz;
1590 case PM_HIBERNATION_PREPARE:
1591 case PM_RESTORE_PREPARE:
1592 case PM_SUSPEND_PREPARE:
1593 atomic_set(&in_suspend, 1);
1595 case PM_POST_HIBERNATION:
1596 case PM_POST_RESTORE:
1597 case PM_POST_SUSPEND:
1598 atomic_set(&in_suspend, 0);
1599 list_for_each_entry(tz, &thermal_tz_list, node) {
1600 if (!thermal_zone_device_is_enabled(tz))
1603 thermal_zone_device_init(tz);
1604 thermal_zone_device_update(tz,
1605 THERMAL_EVENT_UNSPECIFIED);
1614 static struct notifier_block thermal_pm_nb = {
1615 .notifier_call = thermal_pm_notify,
1618 static int __init thermal_init(void)
1622 mutex_init(&poweroff_lock);
1623 result = thermal_register_governors();
1627 result = class_register(&thermal_class);
1629 goto unregister_governors;
1631 result = of_parse_thermal_zones();
1633 goto unregister_class;
1635 result = register_pm_notifier(&thermal_pm_nb);
1637 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1643 class_unregister(&thermal_class);
1644 unregister_governors:
1645 thermal_unregister_governors();
1647 ida_destroy(&thermal_tz_ida);
1648 ida_destroy(&thermal_cdev_ida);
1649 mutex_destroy(&thermal_list_lock);
1650 mutex_destroy(&thermal_governor_lock);
1651 mutex_destroy(&poweroff_lock);
1654 core_initcall(thermal_init);