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,
296 &tz->poll_queue, delay);
298 cancel_delayed_work(&tz->poll_queue);
301 static inline bool should_stop_polling(struct thermal_zone_device *tz)
303 return !thermal_zone_device_is_enabled(tz);
306 static void monitor_thermal_zone(struct thermal_zone_device *tz)
310 stop = should_stop_polling(tz);
312 mutex_lock(&tz->lock);
314 if (!stop && tz->passive)
315 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
316 else if (!stop && tz->polling_delay_jiffies)
317 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
319 thermal_zone_device_set_polling(tz, 0);
321 mutex_unlock(&tz->lock);
324 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
326 tz->governor ? tz->governor->throttle(tz, trip) :
327 def_governor->throttle(tz, trip);
331 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
332 * @work: work_struct associated with the emergency poweroff function
334 * This function is called in very critical situations to force
335 * a kernel poweroff after a configurable timeout value.
337 static void thermal_emergency_poweroff_func(struct work_struct *work)
340 * We have reached here after the emergency thermal shutdown
341 * Waiting period has expired. This means orderly_poweroff has
342 * not been able to shut off the system for some reason.
343 * Try to shut down the system immediately using kernel_power_off
346 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
350 * Worst of the worst case trigger emergency restart
352 WARN(1, "Attempting emergency_restart: Temperature too high\n");
356 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
357 thermal_emergency_poweroff_func);
360 * thermal_emergency_poweroff - Trigger an emergency system poweroff
362 * This may be called from any critical situation to trigger a system shutdown
363 * after a known period of time. By default this is not scheduled.
365 static void thermal_emergency_poweroff(void)
367 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
369 * poweroff_delay_ms must be a carefully profiled positive value.
370 * Its a must for thermal_emergency_poweroff_work to be scheduled
372 if (poweroff_delay_ms <= 0)
374 schedule_delayed_work(&thermal_emergency_poweroff_work,
375 msecs_to_jiffies(poweroff_delay_ms));
378 void thermal_zone_device_critical(struct thermal_zone_device *tz)
380 dev_emerg(&tz->device, "%s: critical temperature reached, "
381 "shutting down\n", tz->type);
383 mutex_lock(&poweroff_lock);
384 if (!power_off_triggered) {
386 * Queue a backup emergency shutdown in the event of
387 * orderly_poweroff failure
389 thermal_emergency_poweroff();
390 orderly_poweroff(true);
391 power_off_triggered = true;
393 mutex_unlock(&poweroff_lock);
395 EXPORT_SYMBOL(thermal_zone_device_critical);
397 static void handle_critical_trips(struct thermal_zone_device *tz,
398 int trip, enum thermal_trip_type trip_type)
402 tz->ops->get_trip_temp(tz, trip, &trip_temp);
404 /* If we have not crossed the trip_temp, we do not care. */
405 if (trip_temp <= 0 || tz->temperature < trip_temp)
408 trace_thermal_zone_trip(tz, trip, trip_type);
410 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
412 else if (trip_type == THERMAL_TRIP_CRITICAL)
413 tz->ops->critical(tz);
416 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
418 enum thermal_trip_type type;
419 int trip_temp, hyst = 0;
421 /* Ignore disabled trip points */
422 if (test_bit(trip, &tz->trips_disabled))
425 tz->ops->get_trip_temp(tz, trip, &trip_temp);
426 tz->ops->get_trip_type(tz, trip, &type);
427 if (tz->ops->get_trip_hyst)
428 tz->ops->get_trip_hyst(tz, trip, &hyst);
430 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
431 if (tz->last_temperature < trip_temp &&
432 tz->temperature >= trip_temp)
433 thermal_notify_tz_trip_up(tz->id, trip);
434 if (tz->last_temperature >= trip_temp &&
435 tz->temperature < (trip_temp - hyst))
436 thermal_notify_tz_trip_down(tz->id, trip);
439 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
440 handle_critical_trips(tz, trip, type);
442 handle_non_critical_trips(tz, trip);
444 * Alright, we handled this trip successfully.
445 * So, start monitoring again.
447 monitor_thermal_zone(tz);
450 static void update_temperature(struct thermal_zone_device *tz)
454 ret = thermal_zone_get_temp(tz, &temp);
457 dev_warn(&tz->device,
458 "failed to read out thermal zone (%d)\n",
463 mutex_lock(&tz->lock);
464 tz->last_temperature = tz->temperature;
465 tz->temperature = temp;
466 mutex_unlock(&tz->lock);
468 trace_thermal_temperature(tz);
470 thermal_genl_sampling_temp(tz->id, temp);
473 static void thermal_zone_device_init(struct thermal_zone_device *tz)
475 struct thermal_instance *pos;
476 tz->temperature = THERMAL_TEMP_INVALID;
477 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
478 pos->initialized = false;
481 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
482 enum thermal_device_mode mode)
486 mutex_lock(&tz->lock);
488 /* do nothing if mode isn't changing */
489 if (mode == tz->mode) {
490 mutex_unlock(&tz->lock);
495 if (tz->ops->change_mode)
496 ret = tz->ops->change_mode(tz, mode);
501 mutex_unlock(&tz->lock);
503 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
505 if (mode == THERMAL_DEVICE_ENABLED)
506 thermal_notify_tz_enable(tz->id);
508 thermal_notify_tz_disable(tz->id);
513 int thermal_zone_device_enable(struct thermal_zone_device *tz)
515 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
517 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
519 int thermal_zone_device_disable(struct thermal_zone_device *tz)
521 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
523 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
525 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
527 enum thermal_device_mode mode;
529 mutex_lock(&tz->lock);
533 mutex_unlock(&tz->lock);
535 return mode == THERMAL_DEVICE_ENABLED;
538 void thermal_zone_device_update(struct thermal_zone_device *tz,
539 enum thermal_notify_event event)
543 if (should_stop_polling(tz))
546 if (atomic_read(&in_suspend))
549 if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
550 "'get_temp' ops set\n", __func__))
553 update_temperature(tz);
555 thermal_zone_set_trips(tz);
557 tz->notify_event = event;
559 for (count = 0; count < tz->trips; count++)
560 handle_thermal_trip(tz, count);
562 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
564 static void thermal_zone_device_check(struct work_struct *work)
566 struct thermal_zone_device *tz = container_of(work, struct
569 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
572 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
575 struct thermal_governor *gov;
578 mutex_lock(&thermal_governor_lock);
579 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
584 mutex_unlock(&thermal_governor_lock);
589 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
592 struct thermal_cooling_device *cdev;
595 mutex_lock(&thermal_list_lock);
596 list_for_each_entry(cdev, &thermal_cdev_list, node) {
597 ret = cb(cdev, data);
601 mutex_unlock(&thermal_list_lock);
606 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
609 struct thermal_zone_device *tz;
612 mutex_lock(&thermal_list_lock);
613 list_for_each_entry(tz, &thermal_tz_list, node) {
618 mutex_unlock(&thermal_list_lock);
623 struct thermal_zone_device *thermal_zone_get_by_id(int id)
625 struct thermal_zone_device *tz, *match = NULL;
627 mutex_lock(&thermal_list_lock);
628 list_for_each_entry(tz, &thermal_tz_list, node) {
634 mutex_unlock(&thermal_list_lock);
640 * Device management section: cooling devices, zones devices, and binding
642 * Set of functions provided by the thermal core for:
643 * - cooling devices lifecycle: registration, unregistration,
644 * binding, and unbinding.
645 * - thermal zone devices lifecycle: registration, unregistration,
646 * binding, and unbinding.
650 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
651 * @tz: pointer to struct thermal_zone_device
652 * @trip: indicates which trip point the cooling devices is
653 * associated with in this thermal zone.
654 * @cdev: pointer to struct thermal_cooling_device
655 * @upper: the Maximum cooling state for this trip point.
656 * THERMAL_NO_LIMIT means no upper limit,
657 * and the cooling device can be in max_state.
658 * @lower: the Minimum cooling state can be used for this trip point.
659 * THERMAL_NO_LIMIT means no lower limit,
660 * and the cooling device can be in cooling state 0.
661 * @weight: The weight of the cooling device to be bound to the
662 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
665 * This interface function bind a thermal cooling device to the certain trip
666 * point of a thermal zone device.
667 * This function is usually called in the thermal zone device .bind callback.
669 * Return: 0 on success, the proper error value otherwise.
671 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
673 struct thermal_cooling_device *cdev,
674 unsigned long upper, unsigned long lower,
677 struct thermal_instance *dev;
678 struct thermal_instance *pos;
679 struct thermal_zone_device *pos1;
680 struct thermal_cooling_device *pos2;
681 unsigned long max_state;
684 if (trip >= tz->trips || trip < 0)
687 list_for_each_entry(pos1, &thermal_tz_list, node) {
691 list_for_each_entry(pos2, &thermal_cdev_list, node) {
696 if (tz != pos1 || cdev != pos2)
699 ret = cdev->ops->get_max_state(cdev, &max_state);
703 /* lower default 0, upper default max_state */
704 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
705 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
707 if (lower > upper || upper > max_state)
710 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
718 dev->target = THERMAL_NO_TARGET;
719 dev->weight = weight;
721 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
726 sprintf(dev->name, "cdev%d", dev->id);
728 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
732 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
733 sysfs_attr_init(&dev->attr.attr);
734 dev->attr.attr.name = dev->attr_name;
735 dev->attr.attr.mode = 0444;
736 dev->attr.show = trip_point_show;
737 result = device_create_file(&tz->device, &dev->attr);
739 goto remove_symbol_link;
741 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
742 sysfs_attr_init(&dev->weight_attr.attr);
743 dev->weight_attr.attr.name = dev->weight_attr_name;
744 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
745 dev->weight_attr.show = weight_show;
746 dev->weight_attr.store = weight_store;
747 result = device_create_file(&tz->device, &dev->weight_attr);
749 goto remove_trip_file;
751 mutex_lock(&tz->lock);
752 mutex_lock(&cdev->lock);
753 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
754 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
759 list_add_tail(&dev->tz_node, &tz->thermal_instances);
760 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
761 atomic_set(&tz->need_update, 1);
763 mutex_unlock(&cdev->lock);
764 mutex_unlock(&tz->lock);
769 device_remove_file(&tz->device, &dev->weight_attr);
771 device_remove_file(&tz->device, &dev->attr);
773 sysfs_remove_link(&tz->device.kobj, dev->name);
775 ida_simple_remove(&tz->ida, dev->id);
780 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
783 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
785 * @tz: pointer to a struct thermal_zone_device.
786 * @trip: indicates which trip point the cooling devices is
787 * associated with in this thermal zone.
788 * @cdev: pointer to a struct thermal_cooling_device.
790 * This interface function unbind a thermal cooling device from the certain
791 * trip point of a thermal zone device.
792 * This function is usually called in the thermal zone device .unbind callback.
794 * Return: 0 on success, the proper error value otherwise.
796 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
798 struct thermal_cooling_device *cdev)
800 struct thermal_instance *pos, *next;
802 mutex_lock(&tz->lock);
803 mutex_lock(&cdev->lock);
804 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
805 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
806 list_del(&pos->tz_node);
807 list_del(&pos->cdev_node);
808 mutex_unlock(&cdev->lock);
809 mutex_unlock(&tz->lock);
813 mutex_unlock(&cdev->lock);
814 mutex_unlock(&tz->lock);
819 device_remove_file(&tz->device, &pos->weight_attr);
820 device_remove_file(&tz->device, &pos->attr);
821 sysfs_remove_link(&tz->device.kobj, pos->name);
822 ida_simple_remove(&tz->ida, pos->id);
826 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
828 static void thermal_release(struct device *dev)
830 struct thermal_zone_device *tz;
831 struct thermal_cooling_device *cdev;
833 if (!strncmp(dev_name(dev), "thermal_zone",
834 sizeof("thermal_zone") - 1)) {
835 tz = to_thermal_zone(dev);
836 thermal_zone_destroy_device_groups(tz);
838 } else if (!strncmp(dev_name(dev), "cooling_device",
839 sizeof("cooling_device") - 1)) {
840 cdev = to_cooling_device(dev);
845 static struct class thermal_class = {
847 .dev_release = thermal_release,
851 void print_bind_err_msg(struct thermal_zone_device *tz,
852 struct thermal_cooling_device *cdev, int ret)
854 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
855 tz->type, cdev->type, ret);
858 static void __bind(struct thermal_zone_device *tz, int mask,
859 struct thermal_cooling_device *cdev,
860 unsigned long *limits,
865 for (i = 0; i < tz->trips; i++) {
866 if (mask & (1 << i)) {
867 unsigned long upper, lower;
869 upper = THERMAL_NO_LIMIT;
870 lower = THERMAL_NO_LIMIT;
872 lower = limits[i * 2];
873 upper = limits[i * 2 + 1];
875 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
879 print_bind_err_msg(tz, cdev, ret);
884 static void bind_cdev(struct thermal_cooling_device *cdev)
887 const struct thermal_zone_params *tzp;
888 struct thermal_zone_device *pos = NULL;
890 mutex_lock(&thermal_list_lock);
892 list_for_each_entry(pos, &thermal_tz_list, node) {
893 if (!pos->tzp && !pos->ops->bind)
896 if (pos->ops->bind) {
897 ret = pos->ops->bind(pos, cdev);
899 print_bind_err_msg(pos, cdev, ret);
904 if (!tzp || !tzp->tbp)
907 for (i = 0; i < tzp->num_tbps; i++) {
908 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
910 if (tzp->tbp[i].match(pos, cdev))
912 tzp->tbp[i].cdev = cdev;
913 __bind(pos, tzp->tbp[i].trip_mask, cdev,
914 tzp->tbp[i].binding_limits,
919 mutex_unlock(&thermal_list_lock);
923 * __thermal_cooling_device_register() - register a new thermal cooling device
924 * @np: a pointer to a device tree node.
925 * @type: the thermal cooling device type.
926 * @devdata: device private data.
927 * @ops: standard thermal cooling devices callbacks.
929 * This interface function adds a new thermal cooling device (fan/processor/...)
930 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
931 * to all the thermal zone devices registered at the same time.
932 * It also gives the opportunity to link the cooling device to a device tree
933 * node, so that it can be bound to a thermal zone created out of device tree.
935 * Return: a pointer to the created struct thermal_cooling_device or an
936 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
938 static struct thermal_cooling_device *
939 __thermal_cooling_device_register(struct device_node *np,
940 const char *type, void *devdata,
941 const struct thermal_cooling_device_ops *ops)
943 struct thermal_cooling_device *cdev;
944 struct thermal_zone_device *pos = NULL;
947 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
949 return ERR_PTR(-EINVAL);
951 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
953 return ERR_PTR(-ENOMEM);
955 ret = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
960 cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
966 mutex_init(&cdev->lock);
967 INIT_LIST_HEAD(&cdev->thermal_instances);
970 cdev->updated = false;
971 cdev->device.class = &thermal_class;
972 cdev->devdata = devdata;
973 thermal_cooling_device_setup_sysfs(cdev);
974 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
975 ret = device_register(&cdev->device);
979 /* Add 'this' new cdev to the global cdev list */
980 mutex_lock(&thermal_list_lock);
981 list_add(&cdev->node, &thermal_cdev_list);
982 mutex_unlock(&thermal_list_lock);
984 /* Update binding information for 'this' new cdev */
987 mutex_lock(&thermal_list_lock);
988 list_for_each_entry(pos, &thermal_tz_list, node)
989 if (atomic_cmpxchg(&pos->need_update, 1, 0))
990 thermal_zone_device_update(pos,
991 THERMAL_EVENT_UNSPECIFIED);
992 mutex_unlock(&thermal_list_lock);
998 put_device(&cdev->device);
1000 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1003 return ERR_PTR(ret);
1007 * thermal_cooling_device_register() - register a new thermal cooling device
1008 * @type: the thermal cooling device type.
1009 * @devdata: device private data.
1010 * @ops: standard thermal cooling devices callbacks.
1012 * This interface function adds a new thermal cooling device (fan/processor/...)
1013 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1014 * to all the thermal zone devices registered at the same time.
1016 * Return: a pointer to the created struct thermal_cooling_device or an
1017 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1019 struct thermal_cooling_device *
1020 thermal_cooling_device_register(const char *type, void *devdata,
1021 const struct thermal_cooling_device_ops *ops)
1023 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1025 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1028 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1029 * @np: a pointer to a device tree node.
1030 * @type: the thermal cooling device type.
1031 * @devdata: device private data.
1032 * @ops: standard thermal cooling devices callbacks.
1034 * This function will register a cooling device with device tree node reference.
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_of_cooling_device_register(struct device_node *np,
1044 const char *type, void *devdata,
1045 const struct thermal_cooling_device_ops *ops)
1047 return __thermal_cooling_device_register(np, type, devdata, ops);
1049 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1051 static void thermal_cooling_device_release(struct device *dev, void *res)
1053 thermal_cooling_device_unregister(
1054 *(struct thermal_cooling_device **)res);
1058 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1060 * @dev: a valid struct device pointer of a sensor device.
1061 * @np: a pointer to a device tree node.
1062 * @type: the thermal cooling device type.
1063 * @devdata: device private data.
1064 * @ops: standard thermal cooling devices callbacks.
1066 * This function will register a cooling device with device tree node reference.
1067 * This interface function adds a new thermal cooling device (fan/processor/...)
1068 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1069 * to all the thermal zone devices registered at the same time.
1071 * Return: a pointer to the created struct thermal_cooling_device or an
1072 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1074 struct thermal_cooling_device *
1075 devm_thermal_of_cooling_device_register(struct device *dev,
1076 struct device_node *np,
1077 char *type, void *devdata,
1078 const struct thermal_cooling_device_ops *ops)
1080 struct thermal_cooling_device **ptr, *tcd;
1082 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1085 return ERR_PTR(-ENOMEM);
1087 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1094 devres_add(dev, ptr);
1098 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1100 static void __unbind(struct thermal_zone_device *tz, int mask,
1101 struct thermal_cooling_device *cdev)
1105 for (i = 0; i < tz->trips; i++)
1106 if (mask & (1 << i))
1107 thermal_zone_unbind_cooling_device(tz, i, cdev);
1111 * thermal_cooling_device_unregister - removes a thermal cooling device
1112 * @cdev: the thermal cooling device to remove.
1114 * thermal_cooling_device_unregister() must be called when a registered
1115 * thermal cooling device is no longer needed.
1117 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1120 const struct thermal_zone_params *tzp;
1121 struct thermal_zone_device *tz;
1122 struct thermal_cooling_device *pos = NULL;
1127 mutex_lock(&thermal_list_lock);
1128 list_for_each_entry(pos, &thermal_cdev_list, node)
1132 /* thermal cooling device not found */
1133 mutex_unlock(&thermal_list_lock);
1136 list_del(&cdev->node);
1138 /* Unbind all thermal zones associated with 'this' cdev */
1139 list_for_each_entry(tz, &thermal_tz_list, node) {
1140 if (tz->ops->unbind) {
1141 tz->ops->unbind(tz, cdev);
1145 if (!tz->tzp || !tz->tzp->tbp)
1149 for (i = 0; i < tzp->num_tbps; i++) {
1150 if (tzp->tbp[i].cdev == cdev) {
1151 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1152 tzp->tbp[i].cdev = NULL;
1157 mutex_unlock(&thermal_list_lock);
1159 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1160 device_del(&cdev->device);
1161 thermal_cooling_device_destroy_sysfs(cdev);
1163 put_device(&cdev->device);
1165 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1167 static void bind_tz(struct thermal_zone_device *tz)
1170 struct thermal_cooling_device *pos = NULL;
1171 const struct thermal_zone_params *tzp = tz->tzp;
1173 if (!tzp && !tz->ops->bind)
1176 mutex_lock(&thermal_list_lock);
1178 /* If there is ops->bind, try to use ops->bind */
1179 if (tz->ops->bind) {
1180 list_for_each_entry(pos, &thermal_cdev_list, node) {
1181 ret = tz->ops->bind(tz, pos);
1183 print_bind_err_msg(tz, pos, ret);
1188 if (!tzp || !tzp->tbp)
1191 list_for_each_entry(pos, &thermal_cdev_list, node) {
1192 for (i = 0; i < tzp->num_tbps; i++) {
1193 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1195 if (tzp->tbp[i].match(tz, pos))
1197 tzp->tbp[i].cdev = pos;
1198 __bind(tz, tzp->tbp[i].trip_mask, pos,
1199 tzp->tbp[i].binding_limits,
1200 tzp->tbp[i].weight);
1204 mutex_unlock(&thermal_list_lock);
1208 * thermal_zone_device_register() - register a new thermal zone device
1209 * @type: the thermal zone device type
1210 * @trips: the number of trip points the thermal zone support
1211 * @mask: a bit string indicating the writeablility of trip points
1212 * @devdata: private device data
1213 * @ops: standard thermal zone device callbacks
1214 * @tzp: thermal zone platform parameters
1215 * @passive_delay: number of milliseconds to wait between polls when
1216 * performing passive cooling
1217 * @polling_delay: number of milliseconds to wait between polls when checking
1218 * whether trip points have been crossed (0 for interrupt
1221 * This interface function adds a new thermal zone device (sensor) to
1222 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1223 * thermal cooling devices registered at the same time.
1224 * thermal_zone_device_unregister() must be called when the device is no
1225 * longer needed. The passive cooling depends on the .get_trend() return value.
1227 * Return: a pointer to the created struct thermal_zone_device or an
1228 * in case of error, an ERR_PTR. Caller must check return value with
1229 * IS_ERR*() helpers.
1231 struct thermal_zone_device *
1232 thermal_zone_device_register(const char *type, int trips, int mask,
1233 void *devdata, struct thermal_zone_device_ops *ops,
1234 struct thermal_zone_params *tzp, int passive_delay,
1237 struct thermal_zone_device *tz;
1238 enum thermal_trip_type trip_type;
1243 struct thermal_governor *governor;
1245 if (!type || strlen(type) == 0) {
1246 pr_err("Error: No thermal zone type defined\n");
1247 return ERR_PTR(-EINVAL);
1250 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1251 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1252 type, THERMAL_NAME_LENGTH);
1253 return ERR_PTR(-EINVAL);
1256 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1257 pr_err("Error: Incorrect number of thermal trips\n");
1258 return ERR_PTR(-EINVAL);
1262 pr_err("Error: Thermal zone device ops not defined\n");
1263 return ERR_PTR(-EINVAL);
1266 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1267 return ERR_PTR(-EINVAL);
1269 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1271 return ERR_PTR(-ENOMEM);
1273 INIT_LIST_HEAD(&tz->thermal_instances);
1275 mutex_init(&tz->lock);
1276 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1283 strlcpy(tz->type, type, sizeof(tz->type));
1286 ops->critical = thermal_zone_device_critical;
1290 tz->device.class = &thermal_class;
1291 tz->devdata = devdata;
1294 thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1295 thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1298 /* Add nodes that are always present via .groups */
1299 result = thermal_zone_create_device_groups(tz, mask);
1303 /* A new thermal zone needs to be updated anyway. */
1304 atomic_set(&tz->need_update, 1);
1306 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1307 result = device_register(&tz->device);
1309 goto release_device;
1311 for (count = 0; count < trips; count++) {
1312 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1313 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1315 set_bit(count, &tz->trips_disabled);
1318 /* Update 'this' zone's governor information */
1319 mutex_lock(&thermal_governor_lock);
1322 governor = __find_governor(tz->tzp->governor_name);
1324 governor = def_governor;
1326 result = thermal_set_governor(tz, governor);
1328 mutex_unlock(&thermal_governor_lock);
1332 mutex_unlock(&thermal_governor_lock);
1334 if (!tz->tzp || !tz->tzp->no_hwmon) {
1335 result = thermal_add_hwmon_sysfs(tz);
1340 mutex_lock(&thermal_list_lock);
1341 list_add_tail(&tz->node, &thermal_tz_list);
1342 mutex_unlock(&thermal_list_lock);
1344 /* Bind cooling devices for this zone */
1347 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1349 thermal_zone_device_init(tz);
1350 /* Update the new thermal zone and mark it as already updated. */
1351 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1352 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1354 thermal_notify_tz_create(tz->id, tz->type);
1359 device_del(&tz->device);
1361 put_device(&tz->device);
1364 ida_simple_remove(&thermal_tz_ida, id);
1367 return ERR_PTR(result);
1369 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1372 * thermal_device_unregister - removes the registered thermal zone device
1373 * @tz: the thermal zone device to remove
1375 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1378 const struct thermal_zone_params *tzp;
1379 struct thermal_cooling_device *cdev;
1380 struct thermal_zone_device *pos = NULL;
1388 mutex_lock(&thermal_list_lock);
1389 list_for_each_entry(pos, &thermal_tz_list, node)
1393 /* thermal zone device not found */
1394 mutex_unlock(&thermal_list_lock);
1397 list_del(&tz->node);
1399 /* Unbind all cdevs associated with 'this' thermal zone */
1400 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1401 if (tz->ops->unbind) {
1402 tz->ops->unbind(tz, cdev);
1406 if (!tzp || !tzp->tbp)
1409 for (i = 0; i < tzp->num_tbps; i++) {
1410 if (tzp->tbp[i].cdev == cdev) {
1411 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1412 tzp->tbp[i].cdev = NULL;
1417 mutex_unlock(&thermal_list_lock);
1419 cancel_delayed_work_sync(&tz->poll_queue);
1421 thermal_set_governor(tz, NULL);
1423 thermal_remove_hwmon_sysfs(tz);
1424 ida_simple_remove(&thermal_tz_ida, tz->id);
1425 ida_destroy(&tz->ida);
1426 mutex_destroy(&tz->lock);
1427 device_unregister(&tz->device);
1429 thermal_notify_tz_delete(tz_id);
1431 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1434 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1435 * @name: thermal zone name to fetch the temperature
1437 * When only one zone is found with the passed name, returns a reference to it.
1439 * Return: On success returns a reference to an unique thermal zone with
1440 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1441 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1443 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1445 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1446 unsigned int found = 0;
1451 mutex_lock(&thermal_list_lock);
1452 list_for_each_entry(pos, &thermal_tz_list, node)
1453 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1457 mutex_unlock(&thermal_list_lock);
1459 /* nothing has been found, thus an error code for it */
1461 ref = ERR_PTR(-ENODEV);
1463 /* Success only when an unique zone is found */
1464 ref = ERR_PTR(-EEXIST);
1469 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1471 static int thermal_pm_notify(struct notifier_block *nb,
1472 unsigned long mode, void *_unused)
1474 struct thermal_zone_device *tz;
1477 case PM_HIBERNATION_PREPARE:
1478 case PM_RESTORE_PREPARE:
1479 case PM_SUSPEND_PREPARE:
1480 atomic_set(&in_suspend, 1);
1482 case PM_POST_HIBERNATION:
1483 case PM_POST_RESTORE:
1484 case PM_POST_SUSPEND:
1485 atomic_set(&in_suspend, 0);
1486 list_for_each_entry(tz, &thermal_tz_list, node) {
1487 if (!thermal_zone_device_is_enabled(tz))
1490 thermal_zone_device_init(tz);
1491 thermal_zone_device_update(tz,
1492 THERMAL_EVENT_UNSPECIFIED);
1501 static struct notifier_block thermal_pm_nb = {
1502 .notifier_call = thermal_pm_notify,
1505 static int __init thermal_init(void)
1509 result = thermal_netlink_init();
1513 result = thermal_register_governors();
1517 result = class_register(&thermal_class);
1519 goto unregister_governors;
1521 result = of_parse_thermal_zones();
1523 goto unregister_class;
1525 result = register_pm_notifier(&thermal_pm_nb);
1527 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1533 class_unregister(&thermal_class);
1534 unregister_governors:
1535 thermal_unregister_governors();
1537 ida_destroy(&thermal_tz_ida);
1538 ida_destroy(&thermal_cdev_ida);
1539 mutex_destroy(&thermal_list_lock);
1540 mutex_destroy(&thermal_governor_lock);
1541 mutex_destroy(&poweroff_lock);
1544 postcore_initcall(thermal_init);