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 void thermal_zone_device_critical(struct thermal_zone_device *tz)
385 dev_emerg(&tz->device, "%s: critical temperature reached, "
386 "shutting down\n", tz->type);
388 mutex_lock(&poweroff_lock);
389 if (!power_off_triggered) {
391 * Queue a backup emergency shutdown in the event of
392 * orderly_poweroff failure
394 thermal_emergency_poweroff();
395 orderly_poweroff(true);
396 power_off_triggered = true;
398 mutex_unlock(&poweroff_lock);
400 EXPORT_SYMBOL(thermal_zone_device_critical);
402 static void handle_critical_trips(struct thermal_zone_device *tz,
403 int trip, enum thermal_trip_type trip_type)
407 tz->ops->get_trip_temp(tz, trip, &trip_temp);
409 /* If we have not crossed the trip_temp, we do not care. */
410 if (trip_temp <= 0 || tz->temperature < trip_temp)
413 trace_thermal_zone_trip(tz, trip, trip_type);
415 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
417 else if (trip_type == THERMAL_TRIP_CRITICAL)
418 tz->ops->critical(tz);
421 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
423 enum thermal_trip_type type;
424 int trip_temp, hyst = 0;
426 /* Ignore disabled trip points */
427 if (test_bit(trip, &tz->trips_disabled))
430 tz->ops->get_trip_temp(tz, trip, &trip_temp);
431 tz->ops->get_trip_type(tz, trip, &type);
432 if (tz->ops->get_trip_hyst)
433 tz->ops->get_trip_hyst(tz, trip, &hyst);
435 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
436 if (tz->last_temperature < trip_temp &&
437 tz->temperature >= trip_temp)
438 thermal_notify_tz_trip_up(tz->id, trip);
439 if (tz->last_temperature >= trip_temp &&
440 tz->temperature < (trip_temp - hyst))
441 thermal_notify_tz_trip_down(tz->id, trip);
444 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
445 handle_critical_trips(tz, trip, type);
447 handle_non_critical_trips(tz, trip);
449 * Alright, we handled this trip successfully.
450 * So, start monitoring again.
452 monitor_thermal_zone(tz);
455 static void update_temperature(struct thermal_zone_device *tz)
459 ret = thermal_zone_get_temp(tz, &temp);
462 dev_warn(&tz->device,
463 "failed to read out thermal zone (%d)\n",
468 mutex_lock(&tz->lock);
469 tz->last_temperature = tz->temperature;
470 tz->temperature = temp;
471 mutex_unlock(&tz->lock);
473 trace_thermal_temperature(tz);
475 thermal_genl_sampling_temp(tz->id, temp);
478 static void thermal_zone_device_init(struct thermal_zone_device *tz)
480 struct thermal_instance *pos;
481 tz->temperature = THERMAL_TEMP_INVALID;
482 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
483 pos->initialized = false;
486 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
489 thermal_zone_device_init(tz);
492 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
493 enum thermal_device_mode mode)
497 mutex_lock(&tz->lock);
499 /* do nothing if mode isn't changing */
500 if (mode == tz->mode) {
501 mutex_unlock(&tz->lock);
506 if (tz->ops->change_mode)
507 ret = tz->ops->change_mode(tz, mode);
512 mutex_unlock(&tz->lock);
514 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
516 if (mode == THERMAL_DEVICE_ENABLED)
517 thermal_notify_tz_enable(tz->id);
519 thermal_notify_tz_disable(tz->id);
524 int thermal_zone_device_enable(struct thermal_zone_device *tz)
526 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
528 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
530 int thermal_zone_device_disable(struct thermal_zone_device *tz)
532 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
534 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
536 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
538 enum thermal_device_mode mode;
540 mutex_lock(&tz->lock);
544 mutex_unlock(&tz->lock);
546 return mode == THERMAL_DEVICE_ENABLED;
549 void thermal_zone_device_update(struct thermal_zone_device *tz,
550 enum thermal_notify_event event)
554 if (should_stop_polling(tz))
557 if (atomic_read(&in_suspend))
560 if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
561 "'get_temp' ops set\n", __func__))
564 update_temperature(tz);
566 thermal_zone_set_trips(tz);
568 tz->notify_event = event;
570 for (count = 0; count < tz->trips; count++)
571 handle_thermal_trip(tz, count);
573 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
576 * thermal_notify_framework - Sensor drivers use this API to notify framework
577 * @tz: thermal zone device
578 * @trip: indicates which trip point has been crossed
580 * This function handles the trip events from sensor drivers. It starts
581 * throttling the cooling devices according to the policy configured.
582 * For CRITICAL and HOT trip points, this notifies the respective drivers,
583 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
584 * The throttling policy is based on the configured platform data; if no
585 * platform data is provided, this uses the step_wise throttling policy.
587 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
589 handle_thermal_trip(tz, trip);
591 EXPORT_SYMBOL_GPL(thermal_notify_framework);
593 static void thermal_zone_device_check(struct work_struct *work)
595 struct thermal_zone_device *tz = container_of(work, struct
598 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
601 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
604 struct thermal_governor *gov;
607 mutex_lock(&thermal_governor_lock);
608 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
613 mutex_unlock(&thermal_governor_lock);
618 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
621 struct thermal_cooling_device *cdev;
624 mutex_lock(&thermal_list_lock);
625 list_for_each_entry(cdev, &thermal_cdev_list, node) {
626 ret = cb(cdev, data);
630 mutex_unlock(&thermal_list_lock);
635 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
638 struct thermal_zone_device *tz;
641 mutex_lock(&thermal_list_lock);
642 list_for_each_entry(tz, &thermal_tz_list, node) {
647 mutex_unlock(&thermal_list_lock);
652 struct thermal_zone_device *thermal_zone_get_by_id(int id)
654 struct thermal_zone_device *tz, *match = NULL;
656 mutex_lock(&thermal_list_lock);
657 list_for_each_entry(tz, &thermal_tz_list, node) {
663 mutex_unlock(&thermal_list_lock);
669 * Device management section: cooling devices, zones devices, and binding
671 * Set of functions provided by the thermal core for:
672 * - cooling devices lifecycle: registration, unregistration,
673 * binding, and unbinding.
674 * - thermal zone devices lifecycle: registration, unregistration,
675 * binding, and unbinding.
679 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
680 * @tz: pointer to struct thermal_zone_device
681 * @trip: indicates which trip point the cooling devices is
682 * associated with in this thermal zone.
683 * @cdev: pointer to struct thermal_cooling_device
684 * @upper: the Maximum cooling state for this trip point.
685 * THERMAL_NO_LIMIT means no upper limit,
686 * and the cooling device can be in max_state.
687 * @lower: the Minimum cooling state can be used for this trip point.
688 * THERMAL_NO_LIMIT means no lower limit,
689 * and the cooling device can be in cooling state 0.
690 * @weight: The weight of the cooling device to be bound to the
691 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
694 * This interface function bind a thermal cooling device to the certain trip
695 * point of a thermal zone device.
696 * This function is usually called in the thermal zone device .bind callback.
698 * Return: 0 on success, the proper error value otherwise.
700 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
702 struct thermal_cooling_device *cdev,
703 unsigned long upper, unsigned long lower,
706 struct thermal_instance *dev;
707 struct thermal_instance *pos;
708 struct thermal_zone_device *pos1;
709 struct thermal_cooling_device *pos2;
710 unsigned long max_state;
713 if (trip >= tz->trips || trip < 0)
716 list_for_each_entry(pos1, &thermal_tz_list, node) {
720 list_for_each_entry(pos2, &thermal_cdev_list, node) {
725 if (tz != pos1 || cdev != pos2)
728 ret = cdev->ops->get_max_state(cdev, &max_state);
732 /* lower default 0, upper default max_state */
733 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
734 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
736 if (lower > upper || upper > max_state)
739 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
747 dev->target = THERMAL_NO_TARGET;
748 dev->weight = weight;
750 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
755 sprintf(dev->name, "cdev%d", dev->id);
757 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
761 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
762 sysfs_attr_init(&dev->attr.attr);
763 dev->attr.attr.name = dev->attr_name;
764 dev->attr.attr.mode = 0444;
765 dev->attr.show = trip_point_show;
766 result = device_create_file(&tz->device, &dev->attr);
768 goto remove_symbol_link;
770 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
771 sysfs_attr_init(&dev->weight_attr.attr);
772 dev->weight_attr.attr.name = dev->weight_attr_name;
773 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
774 dev->weight_attr.show = weight_show;
775 dev->weight_attr.store = weight_store;
776 result = device_create_file(&tz->device, &dev->weight_attr);
778 goto remove_trip_file;
780 mutex_lock(&tz->lock);
781 mutex_lock(&cdev->lock);
782 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
783 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
788 list_add_tail(&dev->tz_node, &tz->thermal_instances);
789 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
790 atomic_set(&tz->need_update, 1);
792 mutex_unlock(&cdev->lock);
793 mutex_unlock(&tz->lock);
798 device_remove_file(&tz->device, &dev->weight_attr);
800 device_remove_file(&tz->device, &dev->attr);
802 sysfs_remove_link(&tz->device.kobj, dev->name);
804 ida_simple_remove(&tz->ida, dev->id);
809 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
812 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
814 * @tz: pointer to a struct thermal_zone_device.
815 * @trip: indicates which trip point the cooling devices is
816 * associated with in this thermal zone.
817 * @cdev: pointer to a struct thermal_cooling_device.
819 * This interface function unbind a thermal cooling device from the certain
820 * trip point of a thermal zone device.
821 * This function is usually called in the thermal zone device .unbind callback.
823 * Return: 0 on success, the proper error value otherwise.
825 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
827 struct thermal_cooling_device *cdev)
829 struct thermal_instance *pos, *next;
831 mutex_lock(&tz->lock);
832 mutex_lock(&cdev->lock);
833 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
834 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
835 list_del(&pos->tz_node);
836 list_del(&pos->cdev_node);
837 mutex_unlock(&cdev->lock);
838 mutex_unlock(&tz->lock);
842 mutex_unlock(&cdev->lock);
843 mutex_unlock(&tz->lock);
848 device_remove_file(&tz->device, &pos->weight_attr);
849 device_remove_file(&tz->device, &pos->attr);
850 sysfs_remove_link(&tz->device.kobj, pos->name);
851 ida_simple_remove(&tz->ida, pos->id);
855 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
857 static void thermal_release(struct device *dev)
859 struct thermal_zone_device *tz;
860 struct thermal_cooling_device *cdev;
862 if (!strncmp(dev_name(dev), "thermal_zone",
863 sizeof("thermal_zone") - 1)) {
864 tz = to_thermal_zone(dev);
865 thermal_zone_destroy_device_groups(tz);
867 } else if (!strncmp(dev_name(dev), "cooling_device",
868 sizeof("cooling_device") - 1)) {
869 cdev = to_cooling_device(dev);
874 static struct class thermal_class = {
876 .dev_release = thermal_release,
880 void print_bind_err_msg(struct thermal_zone_device *tz,
881 struct thermal_cooling_device *cdev, int ret)
883 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
884 tz->type, cdev->type, ret);
887 static void __bind(struct thermal_zone_device *tz, int mask,
888 struct thermal_cooling_device *cdev,
889 unsigned long *limits,
894 for (i = 0; i < tz->trips; i++) {
895 if (mask & (1 << i)) {
896 unsigned long upper, lower;
898 upper = THERMAL_NO_LIMIT;
899 lower = THERMAL_NO_LIMIT;
901 lower = limits[i * 2];
902 upper = limits[i * 2 + 1];
904 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
908 print_bind_err_msg(tz, cdev, ret);
913 static void bind_cdev(struct thermal_cooling_device *cdev)
916 const struct thermal_zone_params *tzp;
917 struct thermal_zone_device *pos = NULL;
919 mutex_lock(&thermal_list_lock);
921 list_for_each_entry(pos, &thermal_tz_list, node) {
922 if (!pos->tzp && !pos->ops->bind)
925 if (pos->ops->bind) {
926 ret = pos->ops->bind(pos, cdev);
928 print_bind_err_msg(pos, cdev, ret);
933 if (!tzp || !tzp->tbp)
936 for (i = 0; i < tzp->num_tbps; i++) {
937 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
939 if (tzp->tbp[i].match(pos, cdev))
941 tzp->tbp[i].cdev = cdev;
942 __bind(pos, tzp->tbp[i].trip_mask, cdev,
943 tzp->tbp[i].binding_limits,
948 mutex_unlock(&thermal_list_lock);
952 * __thermal_cooling_device_register() - register a new thermal cooling device
953 * @np: a pointer to a device tree node.
954 * @type: the thermal cooling device type.
955 * @devdata: device private data.
956 * @ops: standard thermal cooling devices callbacks.
958 * This interface function adds a new thermal cooling device (fan/processor/...)
959 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
960 * to all the thermal zone devices registered at the same time.
961 * It also gives the opportunity to link the cooling device to a device tree
962 * node, so that it can be bound to a thermal zone created out of device tree.
964 * Return: a pointer to the created struct thermal_cooling_device or an
965 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
967 static struct thermal_cooling_device *
968 __thermal_cooling_device_register(struct device_node *np,
969 const char *type, void *devdata,
970 const struct thermal_cooling_device_ops *ops)
972 struct thermal_cooling_device *cdev;
973 struct thermal_zone_device *pos = NULL;
976 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
977 return ERR_PTR(-EINVAL);
979 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
981 return ERR_PTR(-EINVAL);
983 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
985 return ERR_PTR(-ENOMEM);
987 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
990 return ERR_PTR(result);
994 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
995 mutex_init(&cdev->lock);
996 INIT_LIST_HEAD(&cdev->thermal_instances);
999 cdev->updated = false;
1000 cdev->device.class = &thermal_class;
1001 cdev->devdata = devdata;
1002 thermal_cooling_device_setup_sysfs(cdev);
1003 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1004 result = device_register(&cdev->device);
1006 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1007 put_device(&cdev->device);
1008 return ERR_PTR(result);
1011 /* Add 'this' new cdev to the global cdev list */
1012 mutex_lock(&thermal_list_lock);
1013 list_add(&cdev->node, &thermal_cdev_list);
1014 mutex_unlock(&thermal_list_lock);
1016 /* Update binding information for 'this' new cdev */
1019 mutex_lock(&thermal_list_lock);
1020 list_for_each_entry(pos, &thermal_tz_list, node)
1021 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1022 thermal_zone_device_update(pos,
1023 THERMAL_EVENT_UNSPECIFIED);
1024 mutex_unlock(&thermal_list_lock);
1030 * thermal_cooling_device_register() - register a new thermal cooling device
1031 * @type: the thermal cooling device type.
1032 * @devdata: device private data.
1033 * @ops: standard thermal cooling devices callbacks.
1035 * This interface function adds a new thermal cooling device (fan/processor/...)
1036 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1037 * to all the thermal zone devices registered at the same time.
1039 * Return: a pointer to the created struct thermal_cooling_device or an
1040 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1042 struct thermal_cooling_device *
1043 thermal_cooling_device_register(const char *type, void *devdata,
1044 const struct thermal_cooling_device_ops *ops)
1046 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1048 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1051 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1052 * @np: a pointer to a device tree node.
1053 * @type: the thermal cooling device type.
1054 * @devdata: device private data.
1055 * @ops: standard thermal cooling devices callbacks.
1057 * This function will register a cooling device with device tree node reference.
1058 * This interface function adds a new thermal cooling device (fan/processor/...)
1059 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1060 * to all the thermal zone devices registered at the same time.
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 struct thermal_cooling_device *
1066 thermal_of_cooling_device_register(struct device_node *np,
1067 const char *type, void *devdata,
1068 const struct thermal_cooling_device_ops *ops)
1070 return __thermal_cooling_device_register(np, type, devdata, ops);
1072 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1074 static void thermal_cooling_device_release(struct device *dev, void *res)
1076 thermal_cooling_device_unregister(
1077 *(struct thermal_cooling_device **)res);
1081 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1083 * @dev: a valid struct device pointer of a sensor device.
1084 * @np: a pointer to a device tree node.
1085 * @type: the thermal cooling device type.
1086 * @devdata: device private data.
1087 * @ops: standard thermal cooling devices callbacks.
1089 * This function will register a cooling device with device tree node reference.
1090 * This interface function adds a new thermal cooling device (fan/processor/...)
1091 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1092 * to all the thermal zone devices registered at the same time.
1094 * Return: a pointer to the created struct thermal_cooling_device or an
1095 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1097 struct thermal_cooling_device *
1098 devm_thermal_of_cooling_device_register(struct device *dev,
1099 struct device_node *np,
1100 char *type, void *devdata,
1101 const struct thermal_cooling_device_ops *ops)
1103 struct thermal_cooling_device **ptr, *tcd;
1105 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1108 return ERR_PTR(-ENOMEM);
1110 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1117 devres_add(dev, ptr);
1121 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1123 static void __unbind(struct thermal_zone_device *tz, int mask,
1124 struct thermal_cooling_device *cdev)
1128 for (i = 0; i < tz->trips; i++)
1129 if (mask & (1 << i))
1130 thermal_zone_unbind_cooling_device(tz, i, cdev);
1134 * thermal_cooling_device_unregister - removes a thermal cooling device
1135 * @cdev: the thermal cooling device to remove.
1137 * thermal_cooling_device_unregister() must be called when a registered
1138 * thermal cooling device is no longer needed.
1140 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1143 const struct thermal_zone_params *tzp;
1144 struct thermal_zone_device *tz;
1145 struct thermal_cooling_device *pos = NULL;
1150 mutex_lock(&thermal_list_lock);
1151 list_for_each_entry(pos, &thermal_cdev_list, node)
1155 /* thermal cooling device not found */
1156 mutex_unlock(&thermal_list_lock);
1159 list_del(&cdev->node);
1161 /* Unbind all thermal zones associated with 'this' cdev */
1162 list_for_each_entry(tz, &thermal_tz_list, node) {
1163 if (tz->ops->unbind) {
1164 tz->ops->unbind(tz, cdev);
1168 if (!tz->tzp || !tz->tzp->tbp)
1172 for (i = 0; i < tzp->num_tbps; i++) {
1173 if (tzp->tbp[i].cdev == cdev) {
1174 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1175 tzp->tbp[i].cdev = NULL;
1180 mutex_unlock(&thermal_list_lock);
1182 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1183 device_del(&cdev->device);
1184 thermal_cooling_device_destroy_sysfs(cdev);
1185 put_device(&cdev->device);
1187 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1189 static void bind_tz(struct thermal_zone_device *tz)
1192 struct thermal_cooling_device *pos = NULL;
1193 const struct thermal_zone_params *tzp = tz->tzp;
1195 if (!tzp && !tz->ops->bind)
1198 mutex_lock(&thermal_list_lock);
1200 /* If there is ops->bind, try to use ops->bind */
1201 if (tz->ops->bind) {
1202 list_for_each_entry(pos, &thermal_cdev_list, node) {
1203 ret = tz->ops->bind(tz, pos);
1205 print_bind_err_msg(tz, pos, ret);
1210 if (!tzp || !tzp->tbp)
1213 list_for_each_entry(pos, &thermal_cdev_list, node) {
1214 for (i = 0; i < tzp->num_tbps; i++) {
1215 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1217 if (tzp->tbp[i].match(tz, pos))
1219 tzp->tbp[i].cdev = pos;
1220 __bind(tz, tzp->tbp[i].trip_mask, pos,
1221 tzp->tbp[i].binding_limits,
1222 tzp->tbp[i].weight);
1226 mutex_unlock(&thermal_list_lock);
1230 * thermal_zone_device_register() - register a new thermal zone device
1231 * @type: the thermal zone device type
1232 * @trips: the number of trip points the thermal zone support
1233 * @mask: a bit string indicating the writeablility of trip points
1234 * @devdata: private device data
1235 * @ops: standard thermal zone device callbacks
1236 * @tzp: thermal zone platform parameters
1237 * @passive_delay: number of milliseconds to wait between polls when
1238 * performing passive cooling
1239 * @polling_delay: number of milliseconds to wait between polls when checking
1240 * whether trip points have been crossed (0 for interrupt
1243 * This interface function adds a new thermal zone device (sensor) to
1244 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1245 * thermal cooling devices registered at the same time.
1246 * thermal_zone_device_unregister() must be called when the device is no
1247 * longer needed. The passive cooling depends on the .get_trend() return value.
1249 * Return: a pointer to the created struct thermal_zone_device or an
1250 * in case of error, an ERR_PTR. Caller must check return value with
1251 * IS_ERR*() helpers.
1253 struct thermal_zone_device *
1254 thermal_zone_device_register(const char *type, int trips, int mask,
1255 void *devdata, struct thermal_zone_device_ops *ops,
1256 struct thermal_zone_params *tzp, int passive_delay,
1259 struct thermal_zone_device *tz;
1260 enum thermal_trip_type trip_type;
1265 struct thermal_governor *governor;
1267 if (!type || strlen(type) == 0) {
1268 pr_err("Error: No thermal zone type defined\n");
1269 return ERR_PTR(-EINVAL);
1272 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1273 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1274 type, THERMAL_NAME_LENGTH);
1275 return ERR_PTR(-EINVAL);
1278 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1279 pr_err("Error: Incorrect number of thermal trips\n");
1280 return ERR_PTR(-EINVAL);
1284 pr_err("Error: Thermal zone device ops not defined\n");
1285 return ERR_PTR(-EINVAL);
1288 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1289 return ERR_PTR(-EINVAL);
1291 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1293 return ERR_PTR(-ENOMEM);
1295 INIT_LIST_HEAD(&tz->thermal_instances);
1297 mutex_init(&tz->lock);
1298 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1305 strlcpy(tz->type, type, sizeof(tz->type));
1308 ops->critical = thermal_zone_device_critical;
1312 tz->device.class = &thermal_class;
1313 tz->devdata = devdata;
1315 tz->passive_delay = passive_delay;
1316 tz->polling_delay = polling_delay;
1319 /* Add nodes that are always present via .groups */
1320 result = thermal_zone_create_device_groups(tz, mask);
1324 /* A new thermal zone needs to be updated anyway. */
1325 atomic_set(&tz->need_update, 1);
1327 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1328 result = device_register(&tz->device);
1330 goto release_device;
1332 for (count = 0; count < trips; count++) {
1333 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1334 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1336 set_bit(count, &tz->trips_disabled);
1339 /* Update 'this' zone's governor information */
1340 mutex_lock(&thermal_governor_lock);
1343 governor = __find_governor(tz->tzp->governor_name);
1345 governor = def_governor;
1347 result = thermal_set_governor(tz, governor);
1349 mutex_unlock(&thermal_governor_lock);
1353 mutex_unlock(&thermal_governor_lock);
1355 if (!tz->tzp || !tz->tzp->no_hwmon) {
1356 result = thermal_add_hwmon_sysfs(tz);
1361 mutex_lock(&thermal_list_lock);
1362 list_add_tail(&tz->node, &thermal_tz_list);
1363 mutex_unlock(&thermal_list_lock);
1365 /* Bind cooling devices for this zone */
1368 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1370 thermal_zone_device_reset(tz);
1371 /* Update the new thermal zone and mark it as already updated. */
1372 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1373 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1375 thermal_notify_tz_create(tz->id, tz->type);
1380 device_del(&tz->device);
1382 put_device(&tz->device);
1385 ida_simple_remove(&thermal_tz_ida, id);
1388 return ERR_PTR(result);
1390 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1393 * thermal_device_unregister - removes the registered thermal zone device
1394 * @tz: the thermal zone device to remove
1396 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1399 const struct thermal_zone_params *tzp;
1400 struct thermal_cooling_device *cdev;
1401 struct thermal_zone_device *pos = NULL;
1409 mutex_lock(&thermal_list_lock);
1410 list_for_each_entry(pos, &thermal_tz_list, node)
1414 /* thermal zone device not found */
1415 mutex_unlock(&thermal_list_lock);
1418 list_del(&tz->node);
1420 /* Unbind all cdevs associated with 'this' thermal zone */
1421 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1422 if (tz->ops->unbind) {
1423 tz->ops->unbind(tz, cdev);
1427 if (!tzp || !tzp->tbp)
1430 for (i = 0; i < tzp->num_tbps; i++) {
1431 if (tzp->tbp[i].cdev == cdev) {
1432 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1433 tzp->tbp[i].cdev = NULL;
1438 mutex_unlock(&thermal_list_lock);
1440 cancel_delayed_work_sync(&tz->poll_queue);
1442 thermal_set_governor(tz, NULL);
1444 thermal_remove_hwmon_sysfs(tz);
1445 ida_simple_remove(&thermal_tz_ida, tz->id);
1446 ida_destroy(&tz->ida);
1447 mutex_destroy(&tz->lock);
1448 device_unregister(&tz->device);
1450 thermal_notify_tz_delete(tz_id);
1452 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1455 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1456 * @name: thermal zone name to fetch the temperature
1458 * When only one zone is found with the passed name, returns a reference to it.
1460 * Return: On success returns a reference to an unique thermal zone with
1461 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1462 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1464 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1466 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1467 unsigned int found = 0;
1472 mutex_lock(&thermal_list_lock);
1473 list_for_each_entry(pos, &thermal_tz_list, node)
1474 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1478 mutex_unlock(&thermal_list_lock);
1480 /* nothing has been found, thus an error code for it */
1482 ref = ERR_PTR(-ENODEV);
1484 /* Success only when an unique zone is found */
1485 ref = ERR_PTR(-EEXIST);
1490 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1492 static int thermal_pm_notify(struct notifier_block *nb,
1493 unsigned long mode, void *_unused)
1495 struct thermal_zone_device *tz;
1498 case PM_HIBERNATION_PREPARE:
1499 case PM_RESTORE_PREPARE:
1500 case PM_SUSPEND_PREPARE:
1501 atomic_set(&in_suspend, 1);
1503 case PM_POST_HIBERNATION:
1504 case PM_POST_RESTORE:
1505 case PM_POST_SUSPEND:
1506 atomic_set(&in_suspend, 0);
1507 list_for_each_entry(tz, &thermal_tz_list, node) {
1508 if (!thermal_zone_device_is_enabled(tz))
1511 thermal_zone_device_init(tz);
1512 thermal_zone_device_update(tz,
1513 THERMAL_EVENT_UNSPECIFIED);
1522 static struct notifier_block thermal_pm_nb = {
1523 .notifier_call = thermal_pm_notify,
1526 static int __init thermal_init(void)
1530 result = thermal_netlink_init();
1534 result = thermal_register_governors();
1538 result = class_register(&thermal_class);
1540 goto unregister_governors;
1542 result = of_parse_thermal_zones();
1544 goto unregister_class;
1546 result = register_pm_notifier(&thermal_pm_nb);
1548 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1554 class_unregister(&thermal_class);
1555 unregister_governors:
1556 thermal_unregister_governors();
1558 ida_destroy(&thermal_tz_ida);
1559 ida_destroy(&thermal_cdev_ida);
1560 mutex_destroy(&thermal_list_lock);
1561 mutex_destroy(&thermal_governor_lock);
1562 mutex_destroy(&poweroff_lock);
1565 postcore_initcall(thermal_init);