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 void monitor_thermal_zone(struct thermal_zone_device *tz)
306 mutex_lock(&tz->lock);
309 thermal_zone_device_set_polling(tz, tz->passive_delay);
310 else if (tz->polling_delay)
311 thermal_zone_device_set_polling(tz, tz->polling_delay);
313 thermal_zone_device_set_polling(tz, 0);
315 mutex_unlock(&tz->lock);
318 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
320 tz->governor ? tz->governor->throttle(tz, trip) :
321 def_governor->throttle(tz, trip);
325 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
326 * @work: work_struct associated with the emergency poweroff function
328 * This function is called in very critical situations to force
329 * a kernel poweroff after a configurable timeout value.
331 static void thermal_emergency_poweroff_func(struct work_struct *work)
334 * We have reached here after the emergency thermal shutdown
335 * Waiting period has expired. This means orderly_poweroff has
336 * not been able to shut off the system for some reason.
337 * Try to shut down the system immediately using kernel_power_off
340 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
344 * Worst of the worst case trigger emergency restart
346 WARN(1, "Attempting emergency_restart: Temperature too high\n");
350 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
351 thermal_emergency_poweroff_func);
354 * thermal_emergency_poweroff - Trigger an emergency system poweroff
356 * This may be called from any critical situation to trigger a system shutdown
357 * after a known period of time. By default this is not scheduled.
359 static void thermal_emergency_poweroff(void)
361 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
363 * poweroff_delay_ms must be a carefully profiled positive value.
364 * Its a must for thermal_emergency_poweroff_work to be scheduled
366 if (poweroff_delay_ms <= 0)
368 schedule_delayed_work(&thermal_emergency_poweroff_work,
369 msecs_to_jiffies(poweroff_delay_ms));
372 static void handle_critical_trips(struct thermal_zone_device *tz,
373 int trip, enum thermal_trip_type trip_type)
377 tz->ops->get_trip_temp(tz, trip, &trip_temp);
379 /* If we have not crossed the trip_temp, we do not care. */
380 if (trip_temp <= 0 || tz->temperature < trip_temp)
383 trace_thermal_zone_trip(tz, trip, trip_type);
386 tz->ops->notify(tz, trip, trip_type);
388 if (trip_type == THERMAL_TRIP_CRITICAL) {
389 dev_emerg(&tz->device,
390 "critical temperature reached (%d C), shutting down\n",
391 tz->temperature / 1000);
392 mutex_lock(&poweroff_lock);
393 if (!power_off_triggered) {
395 * Queue a backup emergency shutdown in the event of
396 * orderly_poweroff failure
398 thermal_emergency_poweroff();
399 orderly_poweroff(true);
400 power_off_triggered = true;
402 mutex_unlock(&poweroff_lock);
406 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
408 enum thermal_trip_type type;
410 /* Ignore disabled trip points */
411 if (test_bit(trip, &tz->trips_disabled))
414 tz->ops->get_trip_type(tz, trip, &type);
416 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
417 handle_critical_trips(tz, trip, type);
419 handle_non_critical_trips(tz, trip);
421 * Alright, we handled this trip successfully.
422 * So, start monitoring again.
424 monitor_thermal_zone(tz);
427 static void update_temperature(struct thermal_zone_device *tz)
431 ret = thermal_zone_get_temp(tz, &temp);
434 dev_warn(&tz->device,
435 "failed to read out thermal zone (%d)\n",
440 mutex_lock(&tz->lock);
441 tz->last_temperature = tz->temperature;
442 tz->temperature = temp;
443 mutex_unlock(&tz->lock);
445 trace_thermal_temperature(tz);
448 static void thermal_zone_device_init(struct thermal_zone_device *tz)
450 struct thermal_instance *pos;
451 tz->temperature = THERMAL_TEMP_INVALID;
452 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
453 pos->initialized = false;
456 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
459 thermal_zone_device_init(tz);
462 void thermal_zone_device_update(struct thermal_zone_device *tz,
463 enum thermal_notify_event event)
467 if (atomic_read(&in_suspend))
470 if (!tz->ops->get_temp)
473 update_temperature(tz);
475 thermal_zone_set_trips(tz);
477 tz->notify_event = event;
479 for (count = 0; count < tz->trips; count++)
480 handle_thermal_trip(tz, count);
482 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
485 * thermal_notify_framework - Sensor drivers use this API to notify framework
486 * @tz: thermal zone device
487 * @trip: indicates which trip point has been crossed
489 * This function handles the trip events from sensor drivers. It starts
490 * throttling the cooling devices according to the policy configured.
491 * For CRITICAL and HOT trip points, this notifies the respective drivers,
492 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
493 * The throttling policy is based on the configured platform data; if no
494 * platform data is provided, this uses the step_wise throttling policy.
496 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
498 handle_thermal_trip(tz, trip);
500 EXPORT_SYMBOL_GPL(thermal_notify_framework);
502 static void thermal_zone_device_check(struct work_struct *work)
504 struct thermal_zone_device *tz = container_of(work, struct
507 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
511 * Power actor section: interface to power actors to estimate power
513 * Set of functions used to interact to cooling devices that know
514 * how to estimate their devices power consumption.
518 * power_actor_get_max_power() - get the maximum power that a cdev can consume
519 * @cdev: pointer to &thermal_cooling_device
520 * @tz: a valid thermal zone device pointer
521 * @max_power: pointer in which to store the maximum power
523 * Calculate the maximum power consumption in milliwats that the
524 * cooling device can currently consume and store it in @max_power.
526 * Return: 0 on success, -EINVAL if @cdev doesn't support the
527 * power_actor API or -E* on other error.
529 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
530 struct thermal_zone_device *tz, u32 *max_power)
532 if (!cdev_is_power_actor(cdev))
535 return cdev->ops->state2power(cdev, tz, 0, max_power);
539 * power_actor_get_min_power() - get the mainimum power that a cdev can consume
540 * @cdev: pointer to &thermal_cooling_device
541 * @tz: a valid thermal zone device pointer
542 * @min_power: pointer in which to store the minimum power
544 * Calculate the minimum power consumption in milliwatts that the
545 * cooling device can currently consume and store it in @min_power.
547 * Return: 0 on success, -EINVAL if @cdev doesn't support the
548 * power_actor API or -E* on other error.
550 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
551 struct thermal_zone_device *tz, u32 *min_power)
553 unsigned long max_state;
556 if (!cdev_is_power_actor(cdev))
559 ret = cdev->ops->get_max_state(cdev, &max_state);
563 return cdev->ops->state2power(cdev, tz, max_state, min_power);
567 * power_actor_set_power() - limit the maximum power a cooling device consumes
568 * @cdev: pointer to &thermal_cooling_device
569 * @instance: thermal instance to update
570 * @power: the power in milliwatts
572 * Set the cooling device to consume at most @power milliwatts. The limit is
573 * expected to be a cap at the maximum power consumption.
575 * Return: 0 on success, -EINVAL if the cooling device does not
576 * implement the power actor API or -E* for other failures.
578 int power_actor_set_power(struct thermal_cooling_device *cdev,
579 struct thermal_instance *instance, u32 power)
584 if (!cdev_is_power_actor(cdev))
587 ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
591 instance->target = state;
592 mutex_lock(&cdev->lock);
593 cdev->updated = false;
594 mutex_unlock(&cdev->lock);
595 thermal_cdev_update(cdev);
600 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
601 const char *cdev_type, size_t size)
603 struct thermal_cooling_device *cdev = NULL;
605 mutex_lock(&thermal_list_lock);
606 list_for_each_entry(cdev, &thermal_cdev_list, node) {
607 /* skip non matching cdevs */
608 if (strncmp(cdev_type, cdev->type, size))
611 /* re binding the exception matching the type pattern */
612 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
615 THERMAL_WEIGHT_DEFAULT);
617 mutex_unlock(&thermal_list_lock);
620 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
621 const char *cdev_type, size_t size)
623 struct thermal_cooling_device *cdev = NULL;
625 mutex_lock(&thermal_list_lock);
626 list_for_each_entry(cdev, &thermal_cdev_list, node) {
627 /* skip non matching cdevs */
628 if (strncmp(cdev_type, cdev->type, size))
630 /* unbinding the exception matching the type pattern */
631 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
634 mutex_unlock(&thermal_list_lock);
638 * Device management section: cooling devices, zones devices, and binding
640 * Set of functions provided by the thermal core for:
641 * - cooling devices lifecycle: registration, unregistration,
642 * binding, and unbinding.
643 * - thermal zone devices lifecycle: registration, unregistration,
644 * binding, and unbinding.
648 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
649 * @tz: pointer to struct thermal_zone_device
650 * @trip: indicates which trip point the cooling devices is
651 * associated with in this thermal zone.
652 * @cdev: pointer to struct thermal_cooling_device
653 * @upper: the Maximum cooling state for this trip point.
654 * THERMAL_NO_LIMIT means no upper limit,
655 * and the cooling device can be in max_state.
656 * @lower: the Minimum cooling state can be used for this trip point.
657 * THERMAL_NO_LIMIT means no lower limit,
658 * and the cooling device can be in cooling state 0.
659 * @weight: The weight of the cooling device to be bound to the
660 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
663 * This interface function bind a thermal cooling device to the certain trip
664 * point of a thermal zone device.
665 * This function is usually called in the thermal zone device .bind callback.
667 * Return: 0 on success, the proper error value otherwise.
669 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
671 struct thermal_cooling_device *cdev,
672 unsigned long upper, unsigned long lower,
675 struct thermal_instance *dev;
676 struct thermal_instance *pos;
677 struct thermal_zone_device *pos1;
678 struct thermal_cooling_device *pos2;
679 unsigned long max_state;
682 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
685 list_for_each_entry(pos1, &thermal_tz_list, node) {
689 list_for_each_entry(pos2, &thermal_cdev_list, node) {
694 if (tz != pos1 || cdev != pos2)
697 ret = cdev->ops->get_max_state(cdev, &max_state);
701 /* lower default 0, upper default max_state */
702 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
703 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
705 if (lower > upper || upper > max_state)
708 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
716 dev->target = THERMAL_NO_TARGET;
717 dev->weight = weight;
719 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
724 sprintf(dev->name, "cdev%d", dev->id);
726 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
730 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
731 sysfs_attr_init(&dev->attr.attr);
732 dev->attr.attr.name = dev->attr_name;
733 dev->attr.attr.mode = 0444;
734 dev->attr.show = trip_point_show;
735 result = device_create_file(&tz->device, &dev->attr);
737 goto remove_symbol_link;
739 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
740 sysfs_attr_init(&dev->weight_attr.attr);
741 dev->weight_attr.attr.name = dev->weight_attr_name;
742 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
743 dev->weight_attr.show = weight_show;
744 dev->weight_attr.store = weight_store;
745 result = device_create_file(&tz->device, &dev->weight_attr);
747 goto remove_trip_file;
749 mutex_lock(&tz->lock);
750 mutex_lock(&cdev->lock);
751 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
752 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
757 list_add_tail(&dev->tz_node, &tz->thermal_instances);
758 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
759 atomic_set(&tz->need_update, 1);
761 mutex_unlock(&cdev->lock);
762 mutex_unlock(&tz->lock);
767 device_remove_file(&tz->device, &dev->weight_attr);
769 device_remove_file(&tz->device, &dev->attr);
771 sysfs_remove_link(&tz->device.kobj, dev->name);
773 ida_simple_remove(&tz->ida, dev->id);
778 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
781 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
783 * @tz: pointer to a struct thermal_zone_device.
784 * @trip: indicates which trip point the cooling devices is
785 * associated with in this thermal zone.
786 * @cdev: pointer to a struct thermal_cooling_device.
788 * This interface function unbind a thermal cooling device from the certain
789 * trip point of a thermal zone device.
790 * This function is usually called in the thermal zone device .unbind callback.
792 * Return: 0 on success, the proper error value otherwise.
794 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
796 struct thermal_cooling_device *cdev)
798 struct thermal_instance *pos, *next;
800 mutex_lock(&tz->lock);
801 mutex_lock(&cdev->lock);
802 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
803 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
804 list_del(&pos->tz_node);
805 list_del(&pos->cdev_node);
806 mutex_unlock(&cdev->lock);
807 mutex_unlock(&tz->lock);
811 mutex_unlock(&cdev->lock);
812 mutex_unlock(&tz->lock);
817 device_remove_file(&tz->device, &pos->weight_attr);
818 device_remove_file(&tz->device, &pos->attr);
819 sysfs_remove_link(&tz->device.kobj, pos->name);
820 ida_simple_remove(&tz->ida, pos->id);
824 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
826 static void thermal_release(struct device *dev)
828 struct thermal_zone_device *tz;
829 struct thermal_cooling_device *cdev;
831 if (!strncmp(dev_name(dev), "thermal_zone",
832 sizeof("thermal_zone") - 1)) {
833 tz = to_thermal_zone(dev);
834 thermal_zone_destroy_device_groups(tz);
836 } else if (!strncmp(dev_name(dev), "cooling_device",
837 sizeof("cooling_device") - 1)) {
838 cdev = to_cooling_device(dev);
843 static struct class thermal_class = {
845 .dev_release = thermal_release,
849 void print_bind_err_msg(struct thermal_zone_device *tz,
850 struct thermal_cooling_device *cdev, int ret)
852 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
853 tz->type, cdev->type, ret);
856 static void __bind(struct thermal_zone_device *tz, int mask,
857 struct thermal_cooling_device *cdev,
858 unsigned long *limits,
863 for (i = 0; i < tz->trips; i++) {
864 if (mask & (1 << i)) {
865 unsigned long upper, lower;
867 upper = THERMAL_NO_LIMIT;
868 lower = THERMAL_NO_LIMIT;
870 lower = limits[i * 2];
871 upper = limits[i * 2 + 1];
873 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
877 print_bind_err_msg(tz, cdev, ret);
882 static void bind_cdev(struct thermal_cooling_device *cdev)
885 const struct thermal_zone_params *tzp;
886 struct thermal_zone_device *pos = NULL;
888 mutex_lock(&thermal_list_lock);
890 list_for_each_entry(pos, &thermal_tz_list, node) {
891 if (!pos->tzp && !pos->ops->bind)
894 if (pos->ops->bind) {
895 ret = pos->ops->bind(pos, cdev);
897 print_bind_err_msg(pos, cdev, ret);
902 if (!tzp || !tzp->tbp)
905 for (i = 0; i < tzp->num_tbps; i++) {
906 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
908 if (tzp->tbp[i].match(pos, cdev))
910 tzp->tbp[i].cdev = cdev;
911 __bind(pos, tzp->tbp[i].trip_mask, cdev,
912 tzp->tbp[i].binding_limits,
917 mutex_unlock(&thermal_list_lock);
921 * __thermal_cooling_device_register() - register a new thermal cooling device
922 * @np: a pointer to a device tree node.
923 * @type: the thermal cooling device type.
924 * @devdata: device private data.
925 * @ops: standard thermal cooling devices callbacks.
927 * This interface function adds a new thermal cooling device (fan/processor/...)
928 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
929 * to all the thermal zone devices registered at the same time.
930 * It also gives the opportunity to link the cooling device to a device tree
931 * node, so that it can be bound to a thermal zone created out of device tree.
933 * Return: a pointer to the created struct thermal_cooling_device or an
934 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
936 static struct thermal_cooling_device *
937 __thermal_cooling_device_register(struct device_node *np,
938 const char *type, void *devdata,
939 const struct thermal_cooling_device_ops *ops)
941 struct thermal_cooling_device *cdev;
942 struct thermal_zone_device *pos = NULL;
945 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
946 return ERR_PTR(-EINVAL);
948 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
950 return ERR_PTR(-EINVAL);
952 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
954 return ERR_PTR(-ENOMEM);
956 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
959 return ERR_PTR(result);
963 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
964 mutex_init(&cdev->lock);
965 INIT_LIST_HEAD(&cdev->thermal_instances);
968 cdev->updated = false;
969 cdev->device.class = &thermal_class;
970 cdev->devdata = devdata;
971 thermal_cooling_device_setup_sysfs(cdev);
972 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
973 result = device_register(&cdev->device);
975 ida_simple_remove(&thermal_cdev_ida, cdev->id);
976 put_device(&cdev->device);
977 return ERR_PTR(result);
980 /* Add 'this' new cdev to the global cdev list */
981 mutex_lock(&thermal_list_lock);
982 list_add(&cdev->node, &thermal_cdev_list);
983 mutex_unlock(&thermal_list_lock);
985 /* Update binding information for 'this' new cdev */
988 mutex_lock(&thermal_list_lock);
989 list_for_each_entry(pos, &thermal_tz_list, node)
990 if (atomic_cmpxchg(&pos->need_update, 1, 0))
991 thermal_zone_device_update(pos,
992 THERMAL_EVENT_UNSPECIFIED);
993 mutex_unlock(&thermal_list_lock);
999 * thermal_cooling_device_register() - register a new thermal cooling device
1000 * @type: the thermal cooling device type.
1001 * @devdata: device private data.
1002 * @ops: standard thermal cooling devices callbacks.
1004 * This interface function adds a new thermal cooling device (fan/processor/...)
1005 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1006 * to all the thermal zone devices registered at the same time.
1008 * Return: a pointer to the created struct thermal_cooling_device or an
1009 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1011 struct thermal_cooling_device *
1012 thermal_cooling_device_register(const char *type, void *devdata,
1013 const struct thermal_cooling_device_ops *ops)
1015 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1017 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1020 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1021 * @np: a pointer to a device tree node.
1022 * @type: the thermal cooling device type.
1023 * @devdata: device private data.
1024 * @ops: standard thermal cooling devices callbacks.
1026 * This function will register a cooling device with device tree node reference.
1027 * This interface function adds a new thermal cooling device (fan/processor/...)
1028 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1029 * to all the thermal zone devices registered at the same time.
1031 * Return: a pointer to the created struct thermal_cooling_device or an
1032 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1034 struct thermal_cooling_device *
1035 thermal_of_cooling_device_register(struct device_node *np,
1036 const char *type, void *devdata,
1037 const struct thermal_cooling_device_ops *ops)
1039 return __thermal_cooling_device_register(np, type, devdata, ops);
1041 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1043 static void thermal_cooling_device_release(struct device *dev, void *res)
1045 thermal_cooling_device_unregister(
1046 *(struct thermal_cooling_device **)res);
1050 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1052 * @dev: a valid struct device pointer of a sensor device.
1053 * @np: a pointer to a device tree node.
1054 * @type: the thermal cooling device type.
1055 * @devdata: device private data.
1056 * @ops: standard thermal cooling devices callbacks.
1058 * This function will register a cooling device with device tree node reference.
1059 * This interface function adds a new thermal cooling device (fan/processor/...)
1060 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1061 * to all the thermal zone devices registered at the same time.
1063 * Return: a pointer to the created struct thermal_cooling_device or an
1064 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1066 struct thermal_cooling_device *
1067 devm_thermal_of_cooling_device_register(struct device *dev,
1068 struct device_node *np,
1069 char *type, void *devdata,
1070 const struct thermal_cooling_device_ops *ops)
1072 struct thermal_cooling_device **ptr, *tcd;
1074 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1077 return ERR_PTR(-ENOMEM);
1079 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1086 devres_add(dev, ptr);
1090 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1092 static void __unbind(struct thermal_zone_device *tz, int mask,
1093 struct thermal_cooling_device *cdev)
1097 for (i = 0; i < tz->trips; i++)
1098 if (mask & (1 << i))
1099 thermal_zone_unbind_cooling_device(tz, i, cdev);
1103 * thermal_cooling_device_unregister - removes a thermal cooling device
1104 * @cdev: the thermal cooling device to remove.
1106 * thermal_cooling_device_unregister() must be called when a registered
1107 * thermal cooling device is no longer needed.
1109 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1112 const struct thermal_zone_params *tzp;
1113 struct thermal_zone_device *tz;
1114 struct thermal_cooling_device *pos = NULL;
1119 mutex_lock(&thermal_list_lock);
1120 list_for_each_entry(pos, &thermal_cdev_list, node)
1124 /* thermal cooling device not found */
1125 mutex_unlock(&thermal_list_lock);
1128 list_del(&cdev->node);
1130 /* Unbind all thermal zones associated with 'this' cdev */
1131 list_for_each_entry(tz, &thermal_tz_list, node) {
1132 if (tz->ops->unbind) {
1133 tz->ops->unbind(tz, cdev);
1137 if (!tz->tzp || !tz->tzp->tbp)
1141 for (i = 0; i < tzp->num_tbps; i++) {
1142 if (tzp->tbp[i].cdev == cdev) {
1143 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1144 tzp->tbp[i].cdev = NULL;
1149 mutex_unlock(&thermal_list_lock);
1151 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1152 device_del(&cdev->device);
1153 thermal_cooling_device_destroy_sysfs(cdev);
1154 put_device(&cdev->device);
1156 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1158 static void bind_tz(struct thermal_zone_device *tz)
1161 struct thermal_cooling_device *pos = NULL;
1162 const struct thermal_zone_params *tzp = tz->tzp;
1164 if (!tzp && !tz->ops->bind)
1167 mutex_lock(&thermal_list_lock);
1169 /* If there is ops->bind, try to use ops->bind */
1170 if (tz->ops->bind) {
1171 list_for_each_entry(pos, &thermal_cdev_list, node) {
1172 ret = tz->ops->bind(tz, pos);
1174 print_bind_err_msg(tz, pos, ret);
1179 if (!tzp || !tzp->tbp)
1182 list_for_each_entry(pos, &thermal_cdev_list, node) {
1183 for (i = 0; i < tzp->num_tbps; i++) {
1184 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1186 if (tzp->tbp[i].match(tz, pos))
1188 tzp->tbp[i].cdev = pos;
1189 __bind(tz, tzp->tbp[i].trip_mask, pos,
1190 tzp->tbp[i].binding_limits,
1191 tzp->tbp[i].weight);
1195 mutex_unlock(&thermal_list_lock);
1199 * thermal_zone_device_register() - register a new thermal zone device
1200 * @type: the thermal zone device type
1201 * @trips: the number of trip points the thermal zone support
1202 * @mask: a bit string indicating the writeablility of trip points
1203 * @devdata: private device data
1204 * @ops: standard thermal zone device callbacks
1205 * @tzp: thermal zone platform parameters
1206 * @passive_delay: number of milliseconds to wait between polls when
1207 * performing passive cooling
1208 * @polling_delay: number of milliseconds to wait between polls when checking
1209 * whether trip points have been crossed (0 for interrupt
1212 * This interface function adds a new thermal zone device (sensor) to
1213 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1214 * thermal cooling devices registered at the same time.
1215 * thermal_zone_device_unregister() must be called when the device is no
1216 * longer needed. The passive cooling depends on the .get_trend() return value.
1218 * Return: a pointer to the created struct thermal_zone_device or an
1219 * in case of error, an ERR_PTR. Caller must check return value with
1220 * IS_ERR*() helpers.
1222 struct thermal_zone_device *
1223 thermal_zone_device_register(const char *type, int trips, int mask,
1224 void *devdata, struct thermal_zone_device_ops *ops,
1225 struct thermal_zone_params *tzp, int passive_delay,
1228 struct thermal_zone_device *tz;
1229 enum thermal_trip_type trip_type;
1234 struct thermal_governor *governor;
1236 if (!type || strlen(type) == 0) {
1237 pr_err("Error: No thermal zone type defined\n");
1238 return ERR_PTR(-EINVAL);
1241 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1242 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1243 type, THERMAL_NAME_LENGTH);
1244 return ERR_PTR(-EINVAL);
1247 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1248 pr_err("Error: Incorrect number of thermal trips\n");
1249 return ERR_PTR(-EINVAL);
1253 pr_err("Error: Thermal zone device ops not defined\n");
1254 return ERR_PTR(-EINVAL);
1257 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1258 return ERR_PTR(-EINVAL);
1260 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1262 return ERR_PTR(-ENOMEM);
1264 INIT_LIST_HEAD(&tz->thermal_instances);
1266 mutex_init(&tz->lock);
1267 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1274 strlcpy(tz->type, type, sizeof(tz->type));
1277 tz->device.class = &thermal_class;
1278 tz->devdata = devdata;
1280 tz->passive_delay = passive_delay;
1281 tz->polling_delay = polling_delay;
1284 /* Add nodes that are always present via .groups */
1285 result = thermal_zone_create_device_groups(tz, mask);
1289 /* A new thermal zone needs to be updated anyway. */
1290 atomic_set(&tz->need_update, 1);
1292 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1293 result = device_register(&tz->device);
1295 goto release_device;
1297 for (count = 0; count < trips; count++) {
1298 if (tz->ops->get_trip_type(tz, count, &trip_type))
1299 set_bit(count, &tz->trips_disabled);
1300 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1301 set_bit(count, &tz->trips_disabled);
1302 /* Check for bogus trip points */
1304 set_bit(count, &tz->trips_disabled);
1307 /* Update 'this' zone's governor information */
1308 mutex_lock(&thermal_governor_lock);
1311 governor = __find_governor(tz->tzp->governor_name);
1313 governor = def_governor;
1315 result = thermal_set_governor(tz, governor);
1317 mutex_unlock(&thermal_governor_lock);
1321 mutex_unlock(&thermal_governor_lock);
1323 if (!tz->tzp || !tz->tzp->no_hwmon) {
1324 result = thermal_add_hwmon_sysfs(tz);
1329 mutex_lock(&thermal_list_lock);
1330 list_add_tail(&tz->node, &thermal_tz_list);
1331 mutex_unlock(&thermal_list_lock);
1333 /* Bind cooling devices for this zone */
1336 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1338 thermal_zone_device_reset(tz);
1339 /* Update the new thermal zone and mark it as already updated. */
1340 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1341 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1346 device_del(&tz->device);
1348 put_device(&tz->device);
1351 ida_simple_remove(&thermal_tz_ida, id);
1354 return ERR_PTR(result);
1356 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1359 * thermal_device_unregister - removes the registered thermal zone device
1360 * @tz: the thermal zone device to remove
1362 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1365 const struct thermal_zone_params *tzp;
1366 struct thermal_cooling_device *cdev;
1367 struct thermal_zone_device *pos = NULL;
1374 mutex_lock(&thermal_list_lock);
1375 list_for_each_entry(pos, &thermal_tz_list, node)
1379 /* thermal zone device not found */
1380 mutex_unlock(&thermal_list_lock);
1383 list_del(&tz->node);
1385 /* Unbind all cdevs associated with 'this' thermal zone */
1386 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1387 if (tz->ops->unbind) {
1388 tz->ops->unbind(tz, cdev);
1392 if (!tzp || !tzp->tbp)
1395 for (i = 0; i < tzp->num_tbps; i++) {
1396 if (tzp->tbp[i].cdev == cdev) {
1397 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1398 tzp->tbp[i].cdev = NULL;
1403 mutex_unlock(&thermal_list_lock);
1405 cancel_delayed_work_sync(&tz->poll_queue);
1407 thermal_set_governor(tz, NULL);
1409 thermal_remove_hwmon_sysfs(tz);
1410 ida_simple_remove(&thermal_tz_ida, tz->id);
1411 ida_destroy(&tz->ida);
1412 mutex_destroy(&tz->lock);
1413 device_unregister(&tz->device);
1415 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1418 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1419 * @name: thermal zone name to fetch the temperature
1421 * When only one zone is found with the passed name, returns a reference to it.
1423 * Return: On success returns a reference to an unique thermal zone with
1424 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1425 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1427 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1429 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1430 unsigned int found = 0;
1435 mutex_lock(&thermal_list_lock);
1436 list_for_each_entry(pos, &thermal_tz_list, node)
1437 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1441 mutex_unlock(&thermal_list_lock);
1443 /* nothing has been found, thus an error code for it */
1445 ref = ERR_PTR(-ENODEV);
1447 /* Success only when an unique zone is found */
1448 ref = ERR_PTR(-EEXIST);
1453 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1455 static int thermal_pm_notify(struct notifier_block *nb,
1456 unsigned long mode, void *_unused)
1458 struct thermal_zone_device *tz;
1459 enum thermal_device_mode tz_mode;
1462 case PM_HIBERNATION_PREPARE:
1463 case PM_RESTORE_PREPARE:
1464 case PM_SUSPEND_PREPARE:
1465 atomic_set(&in_suspend, 1);
1467 case PM_POST_HIBERNATION:
1468 case PM_POST_RESTORE:
1469 case PM_POST_SUSPEND:
1470 atomic_set(&in_suspend, 0);
1471 list_for_each_entry(tz, &thermal_tz_list, node) {
1472 tz_mode = THERMAL_DEVICE_ENABLED;
1473 if (tz->ops->get_mode)
1474 tz->ops->get_mode(tz, &tz_mode);
1476 if (tz_mode == THERMAL_DEVICE_DISABLED)
1479 thermal_zone_device_init(tz);
1480 thermal_zone_device_update(tz,
1481 THERMAL_EVENT_UNSPECIFIED);
1490 static struct notifier_block thermal_pm_nb = {
1491 .notifier_call = thermal_pm_notify,
1494 static int __init thermal_init(void)
1498 mutex_init(&poweroff_lock);
1499 result = thermal_register_governors();
1503 result = class_register(&thermal_class);
1505 goto unregister_governors;
1507 result = of_parse_thermal_zones();
1509 goto unregister_class;
1511 result = register_pm_notifier(&thermal_pm_nb);
1513 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1519 class_unregister(&thermal_class);
1520 unregister_governors:
1521 thermal_unregister_governors();
1523 ida_destroy(&thermal_tz_ida);
1524 ida_destroy(&thermal_cdev_ida);
1525 mutex_destroy(&thermal_list_lock);
1526 mutex_destroy(&thermal_governor_lock);
1527 mutex_destroy(&poweroff_lock);
1530 core_initcall(thermal_init);