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);
218 thermal_notify_tz_gov_change(tz->id, policy);
223 int thermal_build_list_of_policies(char *buf)
225 struct thermal_governor *pos;
227 ssize_t size = PAGE_SIZE;
229 mutex_lock(&thermal_governor_lock);
231 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
232 size = PAGE_SIZE - count;
233 count += scnprintf(buf + count, size, "%s ", pos->name);
235 count += scnprintf(buf + count, size, "\n");
237 mutex_unlock(&thermal_governor_lock);
242 static void __init thermal_unregister_governors(void)
244 struct thermal_governor **governor;
246 for_each_governor_table(governor)
247 thermal_unregister_governor(*governor);
250 static int __init thermal_register_governors(void)
253 struct thermal_governor **governor;
255 for_each_governor_table(governor) {
256 ret = thermal_register_governor(*governor);
258 pr_err("Failed to register governor: '%s'",
263 pr_info("Registered thermal governor '%s'",
268 struct thermal_governor **gov;
270 for_each_governor_table(gov) {
273 thermal_unregister_governor(*gov);
281 * Zone update section: main control loop applied to each zone while monitoring
283 * in polling mode. The monitoring is done using a workqueue.
284 * Same update may be done on a zone by calling thermal_zone_device_update().
287 * - Non-critical trips will invoke the governor responsible for that zone;
288 * - Hot trips will produce a notification to userspace;
289 * - Critical trip point will cause a system shutdown.
291 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
295 mod_delayed_work(system_freezable_power_efficient_wq,
297 round_jiffies(msecs_to_jiffies(delay)));
299 mod_delayed_work(system_freezable_power_efficient_wq,
301 msecs_to_jiffies(delay));
303 cancel_delayed_work(&tz->poll_queue);
306 static inline bool should_stop_polling(struct thermal_zone_device *tz)
308 return !thermal_zone_device_is_enabled(tz);
311 static void monitor_thermal_zone(struct thermal_zone_device *tz)
315 stop = should_stop_polling(tz);
317 mutex_lock(&tz->lock);
319 if (!stop && tz->passive)
320 thermal_zone_device_set_polling(tz, tz->passive_delay);
321 else if (!stop && tz->polling_delay)
322 thermal_zone_device_set_polling(tz, tz->polling_delay);
324 thermal_zone_device_set_polling(tz, 0);
326 mutex_unlock(&tz->lock);
329 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
331 tz->governor ? tz->governor->throttle(tz, trip) :
332 def_governor->throttle(tz, trip);
336 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
337 * @work: work_struct associated with the emergency poweroff function
339 * This function is called in very critical situations to force
340 * a kernel poweroff after a configurable timeout value.
342 static void thermal_emergency_poweroff_func(struct work_struct *work)
345 * We have reached here after the emergency thermal shutdown
346 * Waiting period has expired. This means orderly_poweroff has
347 * not been able to shut off the system for some reason.
348 * Try to shut down the system immediately using kernel_power_off
351 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
355 * Worst of the worst case trigger emergency restart
357 WARN(1, "Attempting emergency_restart: Temperature too high\n");
361 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
362 thermal_emergency_poweroff_func);
365 * thermal_emergency_poweroff - Trigger an emergency system poweroff
367 * This may be called from any critical situation to trigger a system shutdown
368 * after a known period of time. By default this is not scheduled.
370 static void thermal_emergency_poweroff(void)
372 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
374 * poweroff_delay_ms must be a carefully profiled positive value.
375 * Its a must for thermal_emergency_poweroff_work to be scheduled
377 if (poweroff_delay_ms <= 0)
379 schedule_delayed_work(&thermal_emergency_poweroff_work,
380 msecs_to_jiffies(poweroff_delay_ms));
383 static void handle_critical_trips(struct thermal_zone_device *tz,
384 int trip, enum thermal_trip_type trip_type)
388 tz->ops->get_trip_temp(tz, trip, &trip_temp);
390 /* If we have not crossed the trip_temp, we do not care. */
391 if (trip_temp <= 0 || tz->temperature < trip_temp)
394 trace_thermal_zone_trip(tz, trip, trip_type);
397 tz->ops->notify(tz, trip, trip_type);
399 if (trip_type == THERMAL_TRIP_CRITICAL) {
400 dev_emerg(&tz->device,
401 "critical temperature reached (%d C), shutting down\n",
402 tz->temperature / 1000);
403 mutex_lock(&poweroff_lock);
404 if (!power_off_triggered) {
406 * Queue a backup emergency shutdown in the event of
407 * orderly_poweroff failure
409 thermal_emergency_poweroff();
410 orderly_poweroff(true);
411 power_off_triggered = true;
413 mutex_unlock(&poweroff_lock);
417 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
419 enum thermal_trip_type type;
420 int trip_temp, hyst = 0;
422 /* Ignore disabled trip points */
423 if (test_bit(trip, &tz->trips_disabled))
426 tz->ops->get_trip_temp(tz, trip, &trip_temp);
427 tz->ops->get_trip_type(tz, trip, &type);
428 if (tz->ops->get_trip_hyst)
429 tz->ops->get_trip_hyst(tz, trip, &hyst);
431 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
432 if (tz->last_temperature < trip_temp &&
433 tz->temperature >= trip_temp)
434 thermal_notify_tz_trip_up(tz->id, trip);
435 if (tz->last_temperature >= trip_temp &&
436 tz->temperature < (trip_temp - hyst))
437 thermal_notify_tz_trip_down(tz->id, trip);
440 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
441 handle_critical_trips(tz, trip, type);
443 handle_non_critical_trips(tz, trip);
445 * Alright, we handled this trip successfully.
446 * So, start monitoring again.
448 monitor_thermal_zone(tz);
451 static void update_temperature(struct thermal_zone_device *tz)
455 ret = thermal_zone_get_temp(tz, &temp);
458 dev_warn(&tz->device,
459 "failed to read out thermal zone (%d)\n",
464 mutex_lock(&tz->lock);
465 tz->last_temperature = tz->temperature;
466 tz->temperature = temp;
467 mutex_unlock(&tz->lock);
469 trace_thermal_temperature(tz);
471 thermal_genl_sampling_temp(tz->id, temp);
474 static void thermal_zone_device_init(struct thermal_zone_device *tz)
476 struct thermal_instance *pos;
477 tz->temperature = THERMAL_TEMP_INVALID;
478 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
479 pos->initialized = false;
482 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
485 thermal_zone_device_init(tz);
488 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
489 enum thermal_device_mode mode)
493 mutex_lock(&tz->lock);
495 /* do nothing if mode isn't changing */
496 if (mode == tz->mode) {
497 mutex_unlock(&tz->lock);
502 if (tz->ops->change_mode)
503 ret = tz->ops->change_mode(tz, mode);
508 mutex_unlock(&tz->lock);
510 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
512 if (mode == THERMAL_DEVICE_ENABLED)
513 thermal_notify_tz_enable(tz->id);
515 thermal_notify_tz_disable(tz->id);
520 int thermal_zone_device_enable(struct thermal_zone_device *tz)
522 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
524 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
526 int thermal_zone_device_disable(struct thermal_zone_device *tz)
528 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
530 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
532 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
534 enum thermal_device_mode mode;
536 mutex_lock(&tz->lock);
540 mutex_unlock(&tz->lock);
542 return mode == THERMAL_DEVICE_ENABLED;
545 void thermal_zone_device_update(struct thermal_zone_device *tz,
546 enum thermal_notify_event event)
550 if (should_stop_polling(tz))
553 if (atomic_read(&in_suspend))
556 if (!tz->ops->get_temp)
559 update_temperature(tz);
561 thermal_zone_set_trips(tz);
563 tz->notify_event = event;
565 for (count = 0; count < tz->trips; count++)
566 handle_thermal_trip(tz, count);
568 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
571 * thermal_notify_framework - Sensor drivers use this API to notify framework
572 * @tz: thermal zone device
573 * @trip: indicates which trip point has been crossed
575 * This function handles the trip events from sensor drivers. It starts
576 * throttling the cooling devices according to the policy configured.
577 * For CRITICAL and HOT trip points, this notifies the respective drivers,
578 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
579 * The throttling policy is based on the configured platform data; if no
580 * platform data is provided, this uses the step_wise throttling policy.
582 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
584 handle_thermal_trip(tz, trip);
586 EXPORT_SYMBOL_GPL(thermal_notify_framework);
588 static void thermal_zone_device_check(struct work_struct *work)
590 struct thermal_zone_device *tz = container_of(work, struct
593 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
597 * Power actor section: interface to power actors to estimate power
599 * Set of functions used to interact to cooling devices that know
600 * how to estimate their devices power consumption.
604 * power_actor_get_max_power() - get the maximum power that a cdev can consume
605 * @cdev: pointer to &thermal_cooling_device
606 * @max_power: pointer in which to store the maximum power
608 * Calculate the maximum power consumption in milliwats that the
609 * cooling device can currently consume and store it in @max_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_max_power(struct thermal_cooling_device *cdev,
617 if (!cdev_is_power_actor(cdev))
620 return cdev->ops->state2power(cdev, 0, max_power);
624 * power_actor_get_min_power() - get the mainimum power that a cdev can consume
625 * @cdev: pointer to &thermal_cooling_device
626 * @min_power: pointer in which to store the minimum power
628 * Calculate the minimum power consumption in milliwatts that the
629 * cooling device can currently consume and store it in @min_power.
631 * Return: 0 on success, -EINVAL if @cdev doesn't support the
632 * power_actor API or -E* on other error.
634 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
637 unsigned long max_state;
640 if (!cdev_is_power_actor(cdev))
643 ret = cdev->ops->get_max_state(cdev, &max_state);
647 return cdev->ops->state2power(cdev, max_state, min_power);
651 * power_actor_set_power() - limit the maximum power a cooling device consumes
652 * @cdev: pointer to &thermal_cooling_device
653 * @instance: thermal instance to update
654 * @power: the power in milliwatts
656 * Set the cooling device to consume at most @power milliwatts. The limit is
657 * expected to be a cap at the maximum power consumption.
659 * Return: 0 on success, -EINVAL if the cooling device does not
660 * implement the power actor API or -E* for other failures.
662 int power_actor_set_power(struct thermal_cooling_device *cdev,
663 struct thermal_instance *instance, u32 power)
668 if (!cdev_is_power_actor(cdev))
671 ret = cdev->ops->power2state(cdev, power, &state);
675 instance->target = state;
676 mutex_lock(&cdev->lock);
677 cdev->updated = false;
678 mutex_unlock(&cdev->lock);
679 thermal_cdev_update(cdev);
684 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
685 const char *cdev_type, size_t size)
687 struct thermal_cooling_device *cdev = NULL;
689 mutex_lock(&thermal_list_lock);
690 list_for_each_entry(cdev, &thermal_cdev_list, node) {
691 /* skip non matching cdevs */
692 if (strncmp(cdev_type, cdev->type, size))
695 /* re binding the exception matching the type pattern */
696 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
699 THERMAL_WEIGHT_DEFAULT);
701 mutex_unlock(&thermal_list_lock);
704 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
707 struct thermal_governor *gov;
710 mutex_lock(&thermal_governor_lock);
711 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
716 mutex_unlock(&thermal_governor_lock);
721 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
724 struct thermal_cooling_device *cdev;
727 mutex_lock(&thermal_list_lock);
728 list_for_each_entry(cdev, &thermal_cdev_list, node) {
729 ret = cb(cdev, data);
733 mutex_unlock(&thermal_list_lock);
738 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
741 struct thermal_zone_device *tz;
744 mutex_lock(&thermal_list_lock);
745 list_for_each_entry(tz, &thermal_tz_list, node) {
750 mutex_unlock(&thermal_list_lock);
755 struct thermal_zone_device *thermal_zone_get_by_id(int id)
757 struct thermal_zone_device *tz, *match = NULL;
759 mutex_lock(&thermal_list_lock);
760 list_for_each_entry(tz, &thermal_tz_list, node) {
766 mutex_unlock(&thermal_list_lock);
771 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
772 const char *cdev_type, size_t size)
774 struct thermal_cooling_device *cdev = NULL;
776 mutex_lock(&thermal_list_lock);
777 list_for_each_entry(cdev, &thermal_cdev_list, node) {
778 /* skip non matching cdevs */
779 if (strncmp(cdev_type, cdev->type, size))
781 /* unbinding the exception matching the type pattern */
782 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
785 mutex_unlock(&thermal_list_lock);
789 * Device management section: cooling devices, zones devices, and binding
791 * Set of functions provided by the thermal core for:
792 * - cooling devices lifecycle: registration, unregistration,
793 * binding, and unbinding.
794 * - thermal zone devices lifecycle: registration, unregistration,
795 * binding, and unbinding.
799 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
800 * @tz: pointer to struct thermal_zone_device
801 * @trip: indicates which trip point the cooling devices is
802 * associated with in this thermal zone.
803 * @cdev: pointer to struct thermal_cooling_device
804 * @upper: the Maximum cooling state for this trip point.
805 * THERMAL_NO_LIMIT means no upper limit,
806 * and the cooling device can be in max_state.
807 * @lower: the Minimum cooling state can be used for this trip point.
808 * THERMAL_NO_LIMIT means no lower limit,
809 * and the cooling device can be in cooling state 0.
810 * @weight: The weight of the cooling device to be bound to the
811 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
814 * This interface function bind a thermal cooling device to the certain trip
815 * point of a thermal zone device.
816 * This function is usually called in the thermal zone device .bind callback.
818 * Return: 0 on success, the proper error value otherwise.
820 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
822 struct thermal_cooling_device *cdev,
823 unsigned long upper, unsigned long lower,
826 struct thermal_instance *dev;
827 struct thermal_instance *pos;
828 struct thermal_zone_device *pos1;
829 struct thermal_cooling_device *pos2;
830 unsigned long max_state;
833 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
836 list_for_each_entry(pos1, &thermal_tz_list, node) {
840 list_for_each_entry(pos2, &thermal_cdev_list, node) {
845 if (tz != pos1 || cdev != pos2)
848 ret = cdev->ops->get_max_state(cdev, &max_state);
852 /* lower default 0, upper default max_state */
853 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
854 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
856 if (lower > upper || upper > max_state)
859 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
867 dev->target = THERMAL_NO_TARGET;
868 dev->weight = weight;
870 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
875 sprintf(dev->name, "cdev%d", dev->id);
877 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
881 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
882 sysfs_attr_init(&dev->attr.attr);
883 dev->attr.attr.name = dev->attr_name;
884 dev->attr.attr.mode = 0444;
885 dev->attr.show = trip_point_show;
886 result = device_create_file(&tz->device, &dev->attr);
888 goto remove_symbol_link;
890 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
891 sysfs_attr_init(&dev->weight_attr.attr);
892 dev->weight_attr.attr.name = dev->weight_attr_name;
893 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
894 dev->weight_attr.show = weight_show;
895 dev->weight_attr.store = weight_store;
896 result = device_create_file(&tz->device, &dev->weight_attr);
898 goto remove_trip_file;
900 mutex_lock(&tz->lock);
901 mutex_lock(&cdev->lock);
902 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
903 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
908 list_add_tail(&dev->tz_node, &tz->thermal_instances);
909 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
910 atomic_set(&tz->need_update, 1);
912 mutex_unlock(&cdev->lock);
913 mutex_unlock(&tz->lock);
918 device_remove_file(&tz->device, &dev->weight_attr);
920 device_remove_file(&tz->device, &dev->attr);
922 sysfs_remove_link(&tz->device.kobj, dev->name);
924 ida_simple_remove(&tz->ida, dev->id);
929 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
932 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
934 * @tz: pointer to a struct thermal_zone_device.
935 * @trip: indicates which trip point the cooling devices is
936 * associated with in this thermal zone.
937 * @cdev: pointer to a struct thermal_cooling_device.
939 * This interface function unbind a thermal cooling device from the certain
940 * trip point of a thermal zone device.
941 * This function is usually called in the thermal zone device .unbind callback.
943 * Return: 0 on success, the proper error value otherwise.
945 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
947 struct thermal_cooling_device *cdev)
949 struct thermal_instance *pos, *next;
951 mutex_lock(&tz->lock);
952 mutex_lock(&cdev->lock);
953 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
954 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
955 list_del(&pos->tz_node);
956 list_del(&pos->cdev_node);
957 mutex_unlock(&cdev->lock);
958 mutex_unlock(&tz->lock);
962 mutex_unlock(&cdev->lock);
963 mutex_unlock(&tz->lock);
968 device_remove_file(&tz->device, &pos->weight_attr);
969 device_remove_file(&tz->device, &pos->attr);
970 sysfs_remove_link(&tz->device.kobj, pos->name);
971 ida_simple_remove(&tz->ida, pos->id);
975 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
977 static void thermal_release(struct device *dev)
979 struct thermal_zone_device *tz;
980 struct thermal_cooling_device *cdev;
982 if (!strncmp(dev_name(dev), "thermal_zone",
983 sizeof("thermal_zone") - 1)) {
984 tz = to_thermal_zone(dev);
985 thermal_zone_destroy_device_groups(tz);
987 } else if (!strncmp(dev_name(dev), "cooling_device",
988 sizeof("cooling_device") - 1)) {
989 cdev = to_cooling_device(dev);
994 static struct class thermal_class = {
996 .dev_release = thermal_release,
1000 void print_bind_err_msg(struct thermal_zone_device *tz,
1001 struct thermal_cooling_device *cdev, int ret)
1003 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
1004 tz->type, cdev->type, ret);
1007 static void __bind(struct thermal_zone_device *tz, int mask,
1008 struct thermal_cooling_device *cdev,
1009 unsigned long *limits,
1010 unsigned int weight)
1014 for (i = 0; i < tz->trips; i++) {
1015 if (mask & (1 << i)) {
1016 unsigned long upper, lower;
1018 upper = THERMAL_NO_LIMIT;
1019 lower = THERMAL_NO_LIMIT;
1021 lower = limits[i * 2];
1022 upper = limits[i * 2 + 1];
1024 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
1028 print_bind_err_msg(tz, cdev, ret);
1033 static void bind_cdev(struct thermal_cooling_device *cdev)
1036 const struct thermal_zone_params *tzp;
1037 struct thermal_zone_device *pos = NULL;
1039 mutex_lock(&thermal_list_lock);
1041 list_for_each_entry(pos, &thermal_tz_list, node) {
1042 if (!pos->tzp && !pos->ops->bind)
1045 if (pos->ops->bind) {
1046 ret = pos->ops->bind(pos, cdev);
1048 print_bind_err_msg(pos, cdev, ret);
1053 if (!tzp || !tzp->tbp)
1056 for (i = 0; i < tzp->num_tbps; i++) {
1057 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1059 if (tzp->tbp[i].match(pos, cdev))
1061 tzp->tbp[i].cdev = cdev;
1062 __bind(pos, tzp->tbp[i].trip_mask, cdev,
1063 tzp->tbp[i].binding_limits,
1064 tzp->tbp[i].weight);
1068 mutex_unlock(&thermal_list_lock);
1072 * __thermal_cooling_device_register() - register a new thermal cooling device
1073 * @np: a pointer to a device tree node.
1074 * @type: the thermal cooling device type.
1075 * @devdata: device private data.
1076 * @ops: standard thermal cooling devices callbacks.
1078 * This interface function adds a new thermal cooling device (fan/processor/...)
1079 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1080 * to all the thermal zone devices registered at the same time.
1081 * It also gives the opportunity to link the cooling device to a device tree
1082 * node, so that it can be bound to a thermal zone created out of device tree.
1084 * Return: a pointer to the created struct thermal_cooling_device or an
1085 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1087 static struct thermal_cooling_device *
1088 __thermal_cooling_device_register(struct device_node *np,
1089 const char *type, void *devdata,
1090 const struct thermal_cooling_device_ops *ops)
1092 struct thermal_cooling_device *cdev;
1093 struct thermal_zone_device *pos = NULL;
1096 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1097 return ERR_PTR(-EINVAL);
1099 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1100 !ops->set_cur_state)
1101 return ERR_PTR(-EINVAL);
1103 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1105 return ERR_PTR(-ENOMEM);
1107 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1110 return ERR_PTR(result);
1114 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1115 mutex_init(&cdev->lock);
1116 INIT_LIST_HEAD(&cdev->thermal_instances);
1119 cdev->updated = false;
1120 cdev->device.class = &thermal_class;
1121 cdev->devdata = devdata;
1122 thermal_cooling_device_setup_sysfs(cdev);
1123 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1124 result = device_register(&cdev->device);
1126 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1127 put_device(&cdev->device);
1128 return ERR_PTR(result);
1131 /* Add 'this' new cdev to the global cdev list */
1132 mutex_lock(&thermal_list_lock);
1133 list_add(&cdev->node, &thermal_cdev_list);
1134 mutex_unlock(&thermal_list_lock);
1136 /* Update binding information for 'this' new cdev */
1139 mutex_lock(&thermal_list_lock);
1140 list_for_each_entry(pos, &thermal_tz_list, node)
1141 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1142 thermal_zone_device_update(pos,
1143 THERMAL_EVENT_UNSPECIFIED);
1144 mutex_unlock(&thermal_list_lock);
1150 * thermal_cooling_device_register() - register a new thermal cooling device
1151 * @type: the thermal cooling device type.
1152 * @devdata: device private data.
1153 * @ops: standard thermal cooling devices callbacks.
1155 * This interface function adds a new thermal cooling device (fan/processor/...)
1156 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1157 * to all the thermal zone devices registered at the same time.
1159 * Return: a pointer to the created struct thermal_cooling_device or an
1160 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1162 struct thermal_cooling_device *
1163 thermal_cooling_device_register(const char *type, void *devdata,
1164 const struct thermal_cooling_device_ops *ops)
1166 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1168 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1171 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1172 * @np: a pointer to a device tree node.
1173 * @type: the thermal cooling device type.
1174 * @devdata: device private data.
1175 * @ops: standard thermal cooling devices callbacks.
1177 * This function will register a cooling device with device tree node reference.
1178 * This interface function adds a new thermal cooling device (fan/processor/...)
1179 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1180 * to all the thermal zone devices registered at the same time.
1182 * Return: a pointer to the created struct thermal_cooling_device or an
1183 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1185 struct thermal_cooling_device *
1186 thermal_of_cooling_device_register(struct device_node *np,
1187 const char *type, void *devdata,
1188 const struct thermal_cooling_device_ops *ops)
1190 return __thermal_cooling_device_register(np, type, devdata, ops);
1192 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1194 static void thermal_cooling_device_release(struct device *dev, void *res)
1196 thermal_cooling_device_unregister(
1197 *(struct thermal_cooling_device **)res);
1201 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1203 * @dev: a valid struct device pointer of a sensor device.
1204 * @np: a pointer to a device tree node.
1205 * @type: the thermal cooling device type.
1206 * @devdata: device private data.
1207 * @ops: standard thermal cooling devices callbacks.
1209 * This function will register a cooling device with device tree node reference.
1210 * This interface function adds a new thermal cooling device (fan/processor/...)
1211 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1212 * to all the thermal zone devices registered at the same time.
1214 * Return: a pointer to the created struct thermal_cooling_device or an
1215 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1217 struct thermal_cooling_device *
1218 devm_thermal_of_cooling_device_register(struct device *dev,
1219 struct device_node *np,
1220 char *type, void *devdata,
1221 const struct thermal_cooling_device_ops *ops)
1223 struct thermal_cooling_device **ptr, *tcd;
1225 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1228 return ERR_PTR(-ENOMEM);
1230 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1237 devres_add(dev, ptr);
1241 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1243 static void __unbind(struct thermal_zone_device *tz, int mask,
1244 struct thermal_cooling_device *cdev)
1248 for (i = 0; i < tz->trips; i++)
1249 if (mask & (1 << i))
1250 thermal_zone_unbind_cooling_device(tz, i, cdev);
1254 * thermal_cooling_device_unregister - removes a thermal cooling device
1255 * @cdev: the thermal cooling device to remove.
1257 * thermal_cooling_device_unregister() must be called when a registered
1258 * thermal cooling device is no longer needed.
1260 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1263 const struct thermal_zone_params *tzp;
1264 struct thermal_zone_device *tz;
1265 struct thermal_cooling_device *pos = NULL;
1270 mutex_lock(&thermal_list_lock);
1271 list_for_each_entry(pos, &thermal_cdev_list, node)
1275 /* thermal cooling device not found */
1276 mutex_unlock(&thermal_list_lock);
1279 list_del(&cdev->node);
1281 /* Unbind all thermal zones associated with 'this' cdev */
1282 list_for_each_entry(tz, &thermal_tz_list, node) {
1283 if (tz->ops->unbind) {
1284 tz->ops->unbind(tz, cdev);
1288 if (!tz->tzp || !tz->tzp->tbp)
1292 for (i = 0; i < tzp->num_tbps; i++) {
1293 if (tzp->tbp[i].cdev == cdev) {
1294 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1295 tzp->tbp[i].cdev = NULL;
1300 mutex_unlock(&thermal_list_lock);
1302 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1303 device_del(&cdev->device);
1304 thermal_cooling_device_destroy_sysfs(cdev);
1305 put_device(&cdev->device);
1307 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1309 static void bind_tz(struct thermal_zone_device *tz)
1312 struct thermal_cooling_device *pos = NULL;
1313 const struct thermal_zone_params *tzp = tz->tzp;
1315 if (!tzp && !tz->ops->bind)
1318 mutex_lock(&thermal_list_lock);
1320 /* If there is ops->bind, try to use ops->bind */
1321 if (tz->ops->bind) {
1322 list_for_each_entry(pos, &thermal_cdev_list, node) {
1323 ret = tz->ops->bind(tz, pos);
1325 print_bind_err_msg(tz, pos, ret);
1330 if (!tzp || !tzp->tbp)
1333 list_for_each_entry(pos, &thermal_cdev_list, node) {
1334 for (i = 0; i < tzp->num_tbps; i++) {
1335 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1337 if (tzp->tbp[i].match(tz, pos))
1339 tzp->tbp[i].cdev = pos;
1340 __bind(tz, tzp->tbp[i].trip_mask, pos,
1341 tzp->tbp[i].binding_limits,
1342 tzp->tbp[i].weight);
1346 mutex_unlock(&thermal_list_lock);
1350 * thermal_zone_device_register() - register a new thermal zone device
1351 * @type: the thermal zone device type
1352 * @trips: the number of trip points the thermal zone support
1353 * @mask: a bit string indicating the writeablility of trip points
1354 * @devdata: private device data
1355 * @ops: standard thermal zone device callbacks
1356 * @tzp: thermal zone platform parameters
1357 * @passive_delay: number of milliseconds to wait between polls when
1358 * performing passive cooling
1359 * @polling_delay: number of milliseconds to wait between polls when checking
1360 * whether trip points have been crossed (0 for interrupt
1363 * This interface function adds a new thermal zone device (sensor) to
1364 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1365 * thermal cooling devices registered at the same time.
1366 * thermal_zone_device_unregister() must be called when the device is no
1367 * longer needed. The passive cooling depends on the .get_trend() return value.
1369 * Return: a pointer to the created struct thermal_zone_device or an
1370 * in case of error, an ERR_PTR. Caller must check return value with
1371 * IS_ERR*() helpers.
1373 struct thermal_zone_device *
1374 thermal_zone_device_register(const char *type, int trips, int mask,
1375 void *devdata, struct thermal_zone_device_ops *ops,
1376 struct thermal_zone_params *tzp, int passive_delay,
1379 struct thermal_zone_device *tz;
1380 enum thermal_trip_type trip_type;
1385 struct thermal_governor *governor;
1387 if (!type || strlen(type) == 0) {
1388 pr_err("Error: No thermal zone type defined\n");
1389 return ERR_PTR(-EINVAL);
1392 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1393 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1394 type, THERMAL_NAME_LENGTH);
1395 return ERR_PTR(-EINVAL);
1398 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1399 pr_err("Error: Incorrect number of thermal trips\n");
1400 return ERR_PTR(-EINVAL);
1404 pr_err("Error: Thermal zone device ops not defined\n");
1405 return ERR_PTR(-EINVAL);
1408 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1409 return ERR_PTR(-EINVAL);
1411 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1413 return ERR_PTR(-ENOMEM);
1415 INIT_LIST_HEAD(&tz->thermal_instances);
1417 mutex_init(&tz->lock);
1418 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1425 strlcpy(tz->type, type, sizeof(tz->type));
1428 tz->device.class = &thermal_class;
1429 tz->devdata = devdata;
1431 tz->passive_delay = passive_delay;
1432 tz->polling_delay = polling_delay;
1435 /* Add nodes that are always present via .groups */
1436 result = thermal_zone_create_device_groups(tz, mask);
1440 /* A new thermal zone needs to be updated anyway. */
1441 atomic_set(&tz->need_update, 1);
1443 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1444 result = device_register(&tz->device);
1446 goto release_device;
1448 for (count = 0; count < trips; count++) {
1449 if (tz->ops->get_trip_type(tz, count, &trip_type))
1450 set_bit(count, &tz->trips_disabled);
1451 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1452 set_bit(count, &tz->trips_disabled);
1453 /* Check for bogus trip points */
1455 set_bit(count, &tz->trips_disabled);
1458 /* Update 'this' zone's governor information */
1459 mutex_lock(&thermal_governor_lock);
1462 governor = __find_governor(tz->tzp->governor_name);
1464 governor = def_governor;
1466 result = thermal_set_governor(tz, governor);
1468 mutex_unlock(&thermal_governor_lock);
1472 mutex_unlock(&thermal_governor_lock);
1474 if (!tz->tzp || !tz->tzp->no_hwmon) {
1475 result = thermal_add_hwmon_sysfs(tz);
1480 mutex_lock(&thermal_list_lock);
1481 list_add_tail(&tz->node, &thermal_tz_list);
1482 mutex_unlock(&thermal_list_lock);
1484 /* Bind cooling devices for this zone */
1487 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1489 thermal_zone_device_reset(tz);
1490 /* Update the new thermal zone and mark it as already updated. */
1491 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1492 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1494 thermal_notify_tz_create(tz->id, tz->type);
1499 device_del(&tz->device);
1501 put_device(&tz->device);
1504 ida_simple_remove(&thermal_tz_ida, id);
1507 return ERR_PTR(result);
1509 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1512 * thermal_device_unregister - removes the registered thermal zone device
1513 * @tz: the thermal zone device to remove
1515 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1518 const struct thermal_zone_params *tzp;
1519 struct thermal_cooling_device *cdev;
1520 struct thermal_zone_device *pos = NULL;
1528 mutex_lock(&thermal_list_lock);
1529 list_for_each_entry(pos, &thermal_tz_list, node)
1533 /* thermal zone device not found */
1534 mutex_unlock(&thermal_list_lock);
1537 list_del(&tz->node);
1539 /* Unbind all cdevs associated with 'this' thermal zone */
1540 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1541 if (tz->ops->unbind) {
1542 tz->ops->unbind(tz, cdev);
1546 if (!tzp || !tzp->tbp)
1549 for (i = 0; i < tzp->num_tbps; i++) {
1550 if (tzp->tbp[i].cdev == cdev) {
1551 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1552 tzp->tbp[i].cdev = NULL;
1557 mutex_unlock(&thermal_list_lock);
1559 cancel_delayed_work_sync(&tz->poll_queue);
1561 thermal_set_governor(tz, NULL);
1563 thermal_remove_hwmon_sysfs(tz);
1564 ida_simple_remove(&thermal_tz_ida, tz->id);
1565 ida_destroy(&tz->ida);
1566 mutex_destroy(&tz->lock);
1567 device_unregister(&tz->device);
1569 thermal_notify_tz_delete(tz_id);
1571 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1574 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1575 * @name: thermal zone name to fetch the temperature
1577 * When only one zone is found with the passed name, returns a reference to it.
1579 * Return: On success returns a reference to an unique thermal zone with
1580 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1581 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1583 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1585 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1586 unsigned int found = 0;
1591 mutex_lock(&thermal_list_lock);
1592 list_for_each_entry(pos, &thermal_tz_list, node)
1593 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1597 mutex_unlock(&thermal_list_lock);
1599 /* nothing has been found, thus an error code for it */
1601 ref = ERR_PTR(-ENODEV);
1603 /* Success only when an unique zone is found */
1604 ref = ERR_PTR(-EEXIST);
1609 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1611 static int thermal_pm_notify(struct notifier_block *nb,
1612 unsigned long mode, void *_unused)
1614 struct thermal_zone_device *tz;
1617 case PM_HIBERNATION_PREPARE:
1618 case PM_RESTORE_PREPARE:
1619 case PM_SUSPEND_PREPARE:
1620 atomic_set(&in_suspend, 1);
1622 case PM_POST_HIBERNATION:
1623 case PM_POST_RESTORE:
1624 case PM_POST_SUSPEND:
1625 atomic_set(&in_suspend, 0);
1626 list_for_each_entry(tz, &thermal_tz_list, node) {
1627 if (!thermal_zone_device_is_enabled(tz))
1630 thermal_zone_device_init(tz);
1631 thermal_zone_device_update(tz,
1632 THERMAL_EVENT_UNSPECIFIED);
1641 static struct notifier_block thermal_pm_nb = {
1642 .notifier_call = thermal_pm_notify,
1645 static int __init thermal_init(void)
1649 result = thermal_netlink_init();
1653 result = thermal_register_governors();
1657 result = class_register(&thermal_class);
1659 goto unregister_governors;
1661 result = of_parse_thermal_zones();
1663 goto unregister_class;
1665 result = register_pm_notifier(&thermal_pm_nb);
1667 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1673 class_unregister(&thermal_class);
1674 unregister_governors:
1675 thermal_unregister_governors();
1677 ida_destroy(&thermal_tz_ida);
1678 ida_destroy(&thermal_cdev_ida);
1679 mutex_destroy(&thermal_list_lock);
1680 mutex_destroy(&thermal_governor_lock);
1681 mutex_destroy(&poweroff_lock);
1684 postcore_initcall(thermal_init);