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);
40 static atomic_t in_suspend;
42 static struct thermal_governor *def_governor;
45 * Governor section: set of functions to handle thermal governors
47 * Functions to help in the life cycle of thermal governors within
48 * the thermal core and by the thermal governor code.
51 static struct thermal_governor *__find_governor(const char *name)
53 struct thermal_governor *pos;
55 if (!name || !name[0])
58 list_for_each_entry(pos, &thermal_governor_list, governor_list)
59 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
66 * bind_previous_governor() - bind the previous governor of the thermal zone
67 * @tz: a valid pointer to a struct thermal_zone_device
68 * @failed_gov_name: the name of the governor that failed to register
70 * Register the previous governor of the thermal zone after a new
71 * governor has failed to be bound.
73 static void bind_previous_governor(struct thermal_zone_device *tz,
74 const char *failed_gov_name)
76 if (tz->governor && tz->governor->bind_to_tz) {
77 if (tz->governor->bind_to_tz(tz)) {
79 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
80 failed_gov_name, tz->governor->name, tz->type);
87 * thermal_set_governor() - Switch to another governor
88 * @tz: a valid pointer to a struct thermal_zone_device
89 * @new_gov: pointer to the new governor
91 * Change the governor of thermal zone @tz.
93 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
95 static int thermal_set_governor(struct thermal_zone_device *tz,
96 struct thermal_governor *new_gov)
100 if (tz->governor && tz->governor->unbind_from_tz)
101 tz->governor->unbind_from_tz(tz);
103 if (new_gov && new_gov->bind_to_tz) {
104 ret = new_gov->bind_to_tz(tz);
106 bind_previous_governor(tz, new_gov->name);
112 tz->governor = new_gov;
117 int thermal_register_governor(struct thermal_governor *governor)
121 struct thermal_zone_device *pos;
126 mutex_lock(&thermal_governor_lock);
129 if (!__find_governor(governor->name)) {
133 list_add(&governor->governor_list, &thermal_governor_list);
134 match_default = !strncmp(governor->name,
135 DEFAULT_THERMAL_GOVERNOR,
136 THERMAL_NAME_LENGTH);
138 if (!def_governor && match_default)
139 def_governor = governor;
142 mutex_lock(&thermal_list_lock);
144 list_for_each_entry(pos, &thermal_tz_list, node) {
146 * only thermal zones with specified tz->tzp->governor_name
147 * may run with tz->govenor unset
152 name = pos->tzp->governor_name;
154 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
157 ret = thermal_set_governor(pos, governor);
159 dev_err(&pos->device,
160 "Failed to set governor %s for thermal zone %s: %d\n",
161 governor->name, pos->type, ret);
165 mutex_unlock(&thermal_list_lock);
166 mutex_unlock(&thermal_governor_lock);
171 void thermal_unregister_governor(struct thermal_governor *governor)
173 struct thermal_zone_device *pos;
178 mutex_lock(&thermal_governor_lock);
180 if (!__find_governor(governor->name))
183 mutex_lock(&thermal_list_lock);
185 list_for_each_entry(pos, &thermal_tz_list, node) {
186 if (!strncasecmp(pos->governor->name, governor->name,
187 THERMAL_NAME_LENGTH))
188 thermal_set_governor(pos, NULL);
191 mutex_unlock(&thermal_list_lock);
192 list_del(&governor->governor_list);
194 mutex_unlock(&thermal_governor_lock);
197 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
200 struct thermal_governor *gov;
203 mutex_lock(&thermal_governor_lock);
204 mutex_lock(&tz->lock);
206 gov = __find_governor(strim(policy));
210 ret = thermal_set_governor(tz, gov);
213 mutex_unlock(&tz->lock);
214 mutex_unlock(&thermal_governor_lock);
216 thermal_notify_tz_gov_change(tz->id, policy);
221 int thermal_build_list_of_policies(char *buf)
223 struct thermal_governor *pos;
226 mutex_lock(&thermal_governor_lock);
228 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
229 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
232 count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
234 mutex_unlock(&thermal_governor_lock);
239 static void __init thermal_unregister_governors(void)
241 struct thermal_governor **governor;
243 for_each_governor_table(governor)
244 thermal_unregister_governor(*governor);
247 static int __init thermal_register_governors(void)
250 struct thermal_governor **governor;
252 for_each_governor_table(governor) {
253 ret = thermal_register_governor(*governor);
255 pr_err("Failed to register governor: '%s'",
260 pr_info("Registered thermal governor '%s'",
265 struct thermal_governor **gov;
267 for_each_governor_table(gov) {
270 thermal_unregister_governor(*gov);
278 * Zone update section: main control loop applied to each zone while monitoring
280 * in polling mode. The monitoring is done using a workqueue.
281 * Same update may be done on a zone by calling thermal_zone_device_update().
284 * - Non-critical trips will invoke the governor responsible for that zone;
285 * - Hot trips will produce a notification to userspace;
286 * - Critical trip point will cause a system shutdown.
288 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
292 mod_delayed_work(system_freezable_power_efficient_wq,
293 &tz->poll_queue, delay);
295 cancel_delayed_work(&tz->poll_queue);
298 static inline bool should_stop_polling(struct thermal_zone_device *tz)
300 return !thermal_zone_device_is_enabled(tz);
303 static void monitor_thermal_zone(struct thermal_zone_device *tz)
307 stop = should_stop_polling(tz);
309 mutex_lock(&tz->lock);
311 if (!stop && tz->passive)
312 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
313 else if (!stop && tz->polling_delay_jiffies)
314 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
316 thermal_zone_device_set_polling(tz, 0);
318 mutex_unlock(&tz->lock);
321 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
323 tz->governor ? tz->governor->throttle(tz, trip) :
324 def_governor->throttle(tz, trip);
327 void thermal_zone_device_critical(struct thermal_zone_device *tz)
330 * poweroff_delay_ms must be a carefully profiled positive value.
331 * Its a must for forced_emergency_poweroff_work to be scheduled.
333 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
335 dev_emerg(&tz->device, "%s: critical temperature reached, "
336 "shutting down\n", tz->type);
338 hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
340 EXPORT_SYMBOL(thermal_zone_device_critical);
342 static void handle_critical_trips(struct thermal_zone_device *tz,
343 int trip, enum thermal_trip_type trip_type)
347 tz->ops->get_trip_temp(tz, trip, &trip_temp);
349 /* If we have not crossed the trip_temp, we do not care. */
350 if (trip_temp <= 0 || tz->temperature < trip_temp)
353 trace_thermal_zone_trip(tz, trip, trip_type);
355 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
357 else if (trip_type == THERMAL_TRIP_CRITICAL)
358 tz->ops->critical(tz);
361 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
363 enum thermal_trip_type type;
364 int trip_temp, hyst = 0;
366 /* Ignore disabled trip points */
367 if (test_bit(trip, &tz->trips_disabled))
370 tz->ops->get_trip_temp(tz, trip, &trip_temp);
371 tz->ops->get_trip_type(tz, trip, &type);
372 if (tz->ops->get_trip_hyst)
373 tz->ops->get_trip_hyst(tz, trip, &hyst);
375 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
376 if (tz->last_temperature < trip_temp &&
377 tz->temperature >= trip_temp)
378 thermal_notify_tz_trip_up(tz->id, trip,
380 if (tz->last_temperature >= trip_temp &&
381 tz->temperature < (trip_temp - hyst))
382 thermal_notify_tz_trip_down(tz->id, trip,
386 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
387 handle_critical_trips(tz, trip, type);
389 handle_non_critical_trips(tz, trip);
391 * Alright, we handled this trip successfully.
392 * So, start monitoring again.
394 monitor_thermal_zone(tz);
397 static void update_temperature(struct thermal_zone_device *tz)
401 ret = thermal_zone_get_temp(tz, &temp);
404 dev_warn(&tz->device,
405 "failed to read out thermal zone (%d)\n",
410 mutex_lock(&tz->lock);
411 tz->last_temperature = tz->temperature;
412 tz->temperature = temp;
413 mutex_unlock(&tz->lock);
415 trace_thermal_temperature(tz);
417 thermal_genl_sampling_temp(tz->id, temp);
420 static void thermal_zone_device_init(struct thermal_zone_device *tz)
422 struct thermal_instance *pos;
423 tz->temperature = THERMAL_TEMP_INVALID;
424 tz->prev_low_trip = -INT_MAX;
425 tz->prev_high_trip = INT_MAX;
426 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
427 pos->initialized = false;
430 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
431 enum thermal_device_mode mode)
435 mutex_lock(&tz->lock);
437 /* do nothing if mode isn't changing */
438 if (mode == tz->mode) {
439 mutex_unlock(&tz->lock);
444 if (tz->ops->change_mode)
445 ret = tz->ops->change_mode(tz, mode);
450 mutex_unlock(&tz->lock);
452 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
454 if (mode == THERMAL_DEVICE_ENABLED)
455 thermal_notify_tz_enable(tz->id);
457 thermal_notify_tz_disable(tz->id);
462 int thermal_zone_device_enable(struct thermal_zone_device *tz)
464 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
466 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
468 int thermal_zone_device_disable(struct thermal_zone_device *tz)
470 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
472 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
474 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
476 enum thermal_device_mode mode;
478 mutex_lock(&tz->lock);
482 mutex_unlock(&tz->lock);
484 return mode == THERMAL_DEVICE_ENABLED;
487 void thermal_zone_device_update(struct thermal_zone_device *tz,
488 enum thermal_notify_event event)
492 if (should_stop_polling(tz))
495 if (atomic_read(&in_suspend))
498 if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
499 "'get_temp' ops set\n", __func__))
502 update_temperature(tz);
504 thermal_zone_set_trips(tz);
506 tz->notify_event = event;
508 for (count = 0; count < tz->trips; count++)
509 handle_thermal_trip(tz, count);
511 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
513 static void thermal_zone_device_check(struct work_struct *work)
515 struct thermal_zone_device *tz = container_of(work, struct
518 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
521 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
524 struct thermal_governor *gov;
527 mutex_lock(&thermal_governor_lock);
528 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
533 mutex_unlock(&thermal_governor_lock);
538 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
541 struct thermal_cooling_device *cdev;
544 mutex_lock(&thermal_list_lock);
545 list_for_each_entry(cdev, &thermal_cdev_list, node) {
546 ret = cb(cdev, data);
550 mutex_unlock(&thermal_list_lock);
555 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
558 struct thermal_zone_device *tz;
561 mutex_lock(&thermal_list_lock);
562 list_for_each_entry(tz, &thermal_tz_list, node) {
567 mutex_unlock(&thermal_list_lock);
572 struct thermal_zone_device *thermal_zone_get_by_id(int id)
574 struct thermal_zone_device *tz, *match = NULL;
576 mutex_lock(&thermal_list_lock);
577 list_for_each_entry(tz, &thermal_tz_list, node) {
583 mutex_unlock(&thermal_list_lock);
589 * Device management section: cooling devices, zones devices, and binding
591 * Set of functions provided by the thermal core for:
592 * - cooling devices lifecycle: registration, unregistration,
593 * binding, and unbinding.
594 * - thermal zone devices lifecycle: registration, unregistration,
595 * binding, and unbinding.
599 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
600 * @tz: pointer to struct thermal_zone_device
601 * @trip: indicates which trip point the cooling devices is
602 * associated with in this thermal zone.
603 * @cdev: pointer to struct thermal_cooling_device
604 * @upper: the Maximum cooling state for this trip point.
605 * THERMAL_NO_LIMIT means no upper limit,
606 * and the cooling device can be in max_state.
607 * @lower: the Minimum cooling state can be used for this trip point.
608 * THERMAL_NO_LIMIT means no lower limit,
609 * and the cooling device can be in cooling state 0.
610 * @weight: The weight of the cooling device to be bound to the
611 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
614 * This interface function bind a thermal cooling device to the certain trip
615 * point of a thermal zone device.
616 * This function is usually called in the thermal zone device .bind callback.
618 * Return: 0 on success, the proper error value otherwise.
620 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
622 struct thermal_cooling_device *cdev,
623 unsigned long upper, unsigned long lower,
626 struct thermal_instance *dev;
627 struct thermal_instance *pos;
628 struct thermal_zone_device *pos1;
629 struct thermal_cooling_device *pos2;
630 unsigned long max_state;
633 if (trip >= tz->trips || trip < 0)
636 list_for_each_entry(pos1, &thermal_tz_list, node) {
640 list_for_each_entry(pos2, &thermal_cdev_list, node) {
645 if (tz != pos1 || cdev != pos2)
648 ret = cdev->ops->get_max_state(cdev, &max_state);
652 /* lower default 0, upper default max_state */
653 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
654 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
656 if (lower > upper || upper > max_state)
659 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
667 dev->target = THERMAL_NO_TARGET;
668 dev->weight = weight;
670 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
675 sprintf(dev->name, "cdev%d", dev->id);
677 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
681 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
682 sysfs_attr_init(&dev->attr.attr);
683 dev->attr.attr.name = dev->attr_name;
684 dev->attr.attr.mode = 0444;
685 dev->attr.show = trip_point_show;
686 result = device_create_file(&tz->device, &dev->attr);
688 goto remove_symbol_link;
690 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
691 sysfs_attr_init(&dev->weight_attr.attr);
692 dev->weight_attr.attr.name = dev->weight_attr_name;
693 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
694 dev->weight_attr.show = weight_show;
695 dev->weight_attr.store = weight_store;
696 result = device_create_file(&tz->device, &dev->weight_attr);
698 goto remove_trip_file;
700 mutex_lock(&tz->lock);
701 mutex_lock(&cdev->lock);
702 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
703 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
708 list_add_tail(&dev->tz_node, &tz->thermal_instances);
709 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
710 atomic_set(&tz->need_update, 1);
712 mutex_unlock(&cdev->lock);
713 mutex_unlock(&tz->lock);
718 device_remove_file(&tz->device, &dev->weight_attr);
720 device_remove_file(&tz->device, &dev->attr);
722 sysfs_remove_link(&tz->device.kobj, dev->name);
724 ida_simple_remove(&tz->ida, dev->id);
729 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
732 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
734 * @tz: pointer to a struct thermal_zone_device.
735 * @trip: indicates which trip point the cooling devices is
736 * associated with in this thermal zone.
737 * @cdev: pointer to a struct thermal_cooling_device.
739 * This interface function unbind a thermal cooling device from the certain
740 * trip point of a thermal zone device.
741 * This function is usually called in the thermal zone device .unbind callback.
743 * Return: 0 on success, the proper error value otherwise.
745 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
747 struct thermal_cooling_device *cdev)
749 struct thermal_instance *pos, *next;
751 mutex_lock(&tz->lock);
752 mutex_lock(&cdev->lock);
753 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
754 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
755 list_del(&pos->tz_node);
756 list_del(&pos->cdev_node);
757 mutex_unlock(&cdev->lock);
758 mutex_unlock(&tz->lock);
762 mutex_unlock(&cdev->lock);
763 mutex_unlock(&tz->lock);
768 device_remove_file(&tz->device, &pos->weight_attr);
769 device_remove_file(&tz->device, &pos->attr);
770 sysfs_remove_link(&tz->device.kobj, pos->name);
771 ida_simple_remove(&tz->ida, pos->id);
775 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
777 static void thermal_release(struct device *dev)
779 struct thermal_zone_device *tz;
780 struct thermal_cooling_device *cdev;
782 if (!strncmp(dev_name(dev), "thermal_zone",
783 sizeof("thermal_zone") - 1)) {
784 tz = to_thermal_zone(dev);
785 thermal_zone_destroy_device_groups(tz);
787 } else if (!strncmp(dev_name(dev), "cooling_device",
788 sizeof("cooling_device") - 1)) {
789 cdev = to_cooling_device(dev);
794 static struct class thermal_class = {
796 .dev_release = thermal_release,
800 void print_bind_err_msg(struct thermal_zone_device *tz,
801 struct thermal_cooling_device *cdev, int ret)
803 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
804 tz->type, cdev->type, ret);
807 static void __bind(struct thermal_zone_device *tz, int mask,
808 struct thermal_cooling_device *cdev,
809 unsigned long *limits,
814 for (i = 0; i < tz->trips; i++) {
815 if (mask & (1 << i)) {
816 unsigned long upper, lower;
818 upper = THERMAL_NO_LIMIT;
819 lower = THERMAL_NO_LIMIT;
821 lower = limits[i * 2];
822 upper = limits[i * 2 + 1];
824 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
828 print_bind_err_msg(tz, cdev, ret);
833 static void bind_cdev(struct thermal_cooling_device *cdev)
836 const struct thermal_zone_params *tzp;
837 struct thermal_zone_device *pos = NULL;
839 mutex_lock(&thermal_list_lock);
841 list_for_each_entry(pos, &thermal_tz_list, node) {
842 if (!pos->tzp && !pos->ops->bind)
845 if (pos->ops->bind) {
846 ret = pos->ops->bind(pos, cdev);
848 print_bind_err_msg(pos, cdev, ret);
853 if (!tzp || !tzp->tbp)
856 for (i = 0; i < tzp->num_tbps; i++) {
857 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
859 if (tzp->tbp[i].match(pos, cdev))
861 tzp->tbp[i].cdev = cdev;
862 __bind(pos, tzp->tbp[i].trip_mask, cdev,
863 tzp->tbp[i].binding_limits,
868 mutex_unlock(&thermal_list_lock);
872 * __thermal_cooling_device_register() - register a new thermal cooling device
873 * @np: a pointer to a device tree node.
874 * @type: the thermal cooling device type.
875 * @devdata: device private data.
876 * @ops: standard thermal cooling devices callbacks.
878 * This interface function adds a new thermal cooling device (fan/processor/...)
879 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
880 * to all the thermal zone devices registered at the same time.
881 * It also gives the opportunity to link the cooling device to a device tree
882 * node, so that it can be bound to a thermal zone created out of device tree.
884 * Return: a pointer to the created struct thermal_cooling_device or an
885 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
887 static struct thermal_cooling_device *
888 __thermal_cooling_device_register(struct device_node *np,
889 const char *type, void *devdata,
890 const struct thermal_cooling_device_ops *ops)
892 struct thermal_cooling_device *cdev;
893 struct thermal_zone_device *pos = NULL;
896 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
898 return ERR_PTR(-EINVAL);
900 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
902 return ERR_PTR(-ENOMEM);
904 ret = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
910 ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
914 cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
920 mutex_init(&cdev->lock);
921 INIT_LIST_HEAD(&cdev->thermal_instances);
924 cdev->updated = false;
925 cdev->device.class = &thermal_class;
926 cdev->devdata = devdata;
927 thermal_cooling_device_setup_sysfs(cdev);
928 ret = device_register(&cdev->device);
932 /* Add 'this' new cdev to the global cdev list */
933 mutex_lock(&thermal_list_lock);
934 list_add(&cdev->node, &thermal_cdev_list);
935 mutex_unlock(&thermal_list_lock);
937 /* Update binding information for 'this' new cdev */
940 mutex_lock(&thermal_list_lock);
941 list_for_each_entry(pos, &thermal_tz_list, node)
942 if (atomic_cmpxchg(&pos->need_update, 1, 0))
943 thermal_zone_device_update(pos,
944 THERMAL_EVENT_UNSPECIFIED);
945 mutex_unlock(&thermal_list_lock);
951 put_device(&cdev->device);
954 ida_simple_remove(&thermal_cdev_ida, id);
961 * thermal_cooling_device_register() - register a new thermal cooling device
962 * @type: the thermal cooling device type.
963 * @devdata: device private data.
964 * @ops: standard thermal cooling devices callbacks.
966 * This interface function adds a new thermal cooling device (fan/processor/...)
967 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
968 * to all the thermal zone devices registered at the same time.
970 * Return: a pointer to the created struct thermal_cooling_device or an
971 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
973 struct thermal_cooling_device *
974 thermal_cooling_device_register(const char *type, void *devdata,
975 const struct thermal_cooling_device_ops *ops)
977 return __thermal_cooling_device_register(NULL, type, devdata, ops);
979 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
982 * thermal_of_cooling_device_register() - register an OF thermal cooling device
983 * @np: a pointer to a device tree node.
984 * @type: the thermal cooling device type.
985 * @devdata: device private data.
986 * @ops: standard thermal cooling devices callbacks.
988 * This function will register a cooling device with device tree node reference.
989 * This interface function adds a new thermal cooling device (fan/processor/...)
990 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
991 * to all the thermal zone devices registered at the same time.
993 * Return: a pointer to the created struct thermal_cooling_device or an
994 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
996 struct thermal_cooling_device *
997 thermal_of_cooling_device_register(struct device_node *np,
998 const char *type, void *devdata,
999 const struct thermal_cooling_device_ops *ops)
1001 return __thermal_cooling_device_register(np, type, devdata, ops);
1003 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1005 static void thermal_cooling_device_release(struct device *dev, void *res)
1007 thermal_cooling_device_unregister(
1008 *(struct thermal_cooling_device **)res);
1012 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1014 * @dev: a valid struct device pointer of a sensor device.
1015 * @np: a pointer to a device tree node.
1016 * @type: the thermal cooling device type.
1017 * @devdata: device private data.
1018 * @ops: standard thermal cooling devices callbacks.
1020 * This function will register a cooling device with device tree node reference.
1021 * This interface function adds a new thermal cooling device (fan/processor/...)
1022 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1023 * to all the thermal zone devices registered at the same time.
1025 * Return: a pointer to the created struct thermal_cooling_device or an
1026 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1028 struct thermal_cooling_device *
1029 devm_thermal_of_cooling_device_register(struct device *dev,
1030 struct device_node *np,
1031 char *type, void *devdata,
1032 const struct thermal_cooling_device_ops *ops)
1034 struct thermal_cooling_device **ptr, *tcd;
1036 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1039 return ERR_PTR(-ENOMEM);
1041 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1048 devres_add(dev, ptr);
1052 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1054 static void __unbind(struct thermal_zone_device *tz, int mask,
1055 struct thermal_cooling_device *cdev)
1059 for (i = 0; i < tz->trips; i++)
1060 if (mask & (1 << i))
1061 thermal_zone_unbind_cooling_device(tz, i, cdev);
1065 * thermal_cooling_device_unregister - removes a thermal cooling device
1066 * @cdev: the thermal cooling device to remove.
1068 * thermal_cooling_device_unregister() must be called when a registered
1069 * thermal cooling device is no longer needed.
1071 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1074 const struct thermal_zone_params *tzp;
1075 struct thermal_zone_device *tz;
1076 struct thermal_cooling_device *pos = NULL;
1081 mutex_lock(&thermal_list_lock);
1082 list_for_each_entry(pos, &thermal_cdev_list, node)
1086 /* thermal cooling device not found */
1087 mutex_unlock(&thermal_list_lock);
1090 list_del(&cdev->node);
1092 /* Unbind all thermal zones associated with 'this' cdev */
1093 list_for_each_entry(tz, &thermal_tz_list, node) {
1094 if (tz->ops->unbind) {
1095 tz->ops->unbind(tz, cdev);
1099 if (!tz->tzp || !tz->tzp->tbp)
1103 for (i = 0; i < tzp->num_tbps; i++) {
1104 if (tzp->tbp[i].cdev == cdev) {
1105 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1106 tzp->tbp[i].cdev = NULL;
1111 mutex_unlock(&thermal_list_lock);
1113 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1114 device_del(&cdev->device);
1115 thermal_cooling_device_destroy_sysfs(cdev);
1117 put_device(&cdev->device);
1119 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1121 static void bind_tz(struct thermal_zone_device *tz)
1124 struct thermal_cooling_device *pos = NULL;
1125 const struct thermal_zone_params *tzp = tz->tzp;
1127 if (!tzp && !tz->ops->bind)
1130 mutex_lock(&thermal_list_lock);
1132 /* If there is ops->bind, try to use ops->bind */
1133 if (tz->ops->bind) {
1134 list_for_each_entry(pos, &thermal_cdev_list, node) {
1135 ret = tz->ops->bind(tz, pos);
1137 print_bind_err_msg(tz, pos, ret);
1142 if (!tzp || !tzp->tbp)
1145 list_for_each_entry(pos, &thermal_cdev_list, node) {
1146 for (i = 0; i < tzp->num_tbps; i++) {
1147 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1149 if (tzp->tbp[i].match(tz, pos))
1151 tzp->tbp[i].cdev = pos;
1152 __bind(tz, tzp->tbp[i].trip_mask, pos,
1153 tzp->tbp[i].binding_limits,
1154 tzp->tbp[i].weight);
1158 mutex_unlock(&thermal_list_lock);
1162 * thermal_zone_device_register() - register a new thermal zone device
1163 * @type: the thermal zone device type
1164 * @trips: the number of trip points the thermal zone support
1165 * @mask: a bit string indicating the writeablility of trip points
1166 * @devdata: private device data
1167 * @ops: standard thermal zone device callbacks
1168 * @tzp: thermal zone platform parameters
1169 * @passive_delay: number of milliseconds to wait between polls when
1170 * performing passive cooling
1171 * @polling_delay: number of milliseconds to wait between polls when checking
1172 * whether trip points have been crossed (0 for interrupt
1175 * This interface function adds a new thermal zone device (sensor) to
1176 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1177 * thermal cooling devices registered at the same time.
1178 * thermal_zone_device_unregister() must be called when the device is no
1179 * longer needed. The passive cooling depends on the .get_trend() return value.
1181 * Return: a pointer to the created struct thermal_zone_device or an
1182 * in case of error, an ERR_PTR. Caller must check return value with
1183 * IS_ERR*() helpers.
1185 struct thermal_zone_device *
1186 thermal_zone_device_register(const char *type, int trips, int mask,
1187 void *devdata, struct thermal_zone_device_ops *ops,
1188 struct thermal_zone_params *tzp, int passive_delay,
1191 struct thermal_zone_device *tz;
1192 enum thermal_trip_type trip_type;
1197 struct thermal_governor *governor;
1199 if (!type || strlen(type) == 0) {
1200 pr_err("Error: No thermal zone type defined\n");
1201 return ERR_PTR(-EINVAL);
1204 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1205 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1206 type, THERMAL_NAME_LENGTH);
1207 return ERR_PTR(-EINVAL);
1210 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1211 pr_err("Error: Incorrect number of thermal trips\n");
1212 return ERR_PTR(-EINVAL);
1216 pr_err("Error: Thermal zone device ops not defined\n");
1217 return ERR_PTR(-EINVAL);
1220 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1221 return ERR_PTR(-EINVAL);
1223 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1225 return ERR_PTR(-ENOMEM);
1227 INIT_LIST_HEAD(&tz->thermal_instances);
1229 mutex_init(&tz->lock);
1230 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1237 strlcpy(tz->type, type, sizeof(tz->type));
1239 result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1244 ops->critical = thermal_zone_device_critical;
1248 tz->device.class = &thermal_class;
1249 tz->devdata = devdata;
1252 thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1253 thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1256 /* Add nodes that are always present via .groups */
1257 result = thermal_zone_create_device_groups(tz, mask);
1261 /* A new thermal zone needs to be updated anyway. */
1262 atomic_set(&tz->need_update, 1);
1264 result = device_register(&tz->device);
1266 goto release_device;
1268 for (count = 0; count < trips; count++) {
1269 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1270 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1272 set_bit(count, &tz->trips_disabled);
1275 /* Update 'this' zone's governor information */
1276 mutex_lock(&thermal_governor_lock);
1279 governor = __find_governor(tz->tzp->governor_name);
1281 governor = def_governor;
1283 result = thermal_set_governor(tz, governor);
1285 mutex_unlock(&thermal_governor_lock);
1289 mutex_unlock(&thermal_governor_lock);
1291 if (!tz->tzp || !tz->tzp->no_hwmon) {
1292 result = thermal_add_hwmon_sysfs(tz);
1297 mutex_lock(&thermal_list_lock);
1298 list_add_tail(&tz->node, &thermal_tz_list);
1299 mutex_unlock(&thermal_list_lock);
1301 /* Bind cooling devices for this zone */
1304 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1306 thermal_zone_device_init(tz);
1307 /* Update the new thermal zone and mark it as already updated. */
1308 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1309 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1311 thermal_notify_tz_create(tz->id, tz->type);
1316 device_del(&tz->device);
1318 put_device(&tz->device);
1321 ida_simple_remove(&thermal_tz_ida, id);
1324 return ERR_PTR(result);
1326 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1329 * thermal_zone_device_unregister - removes the registered thermal zone device
1330 * @tz: the thermal zone device to remove
1332 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1335 const struct thermal_zone_params *tzp;
1336 struct thermal_cooling_device *cdev;
1337 struct thermal_zone_device *pos = NULL;
1345 mutex_lock(&thermal_list_lock);
1346 list_for_each_entry(pos, &thermal_tz_list, node)
1350 /* thermal zone device not found */
1351 mutex_unlock(&thermal_list_lock);
1354 list_del(&tz->node);
1356 /* Unbind all cdevs associated with 'this' thermal zone */
1357 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1358 if (tz->ops->unbind) {
1359 tz->ops->unbind(tz, cdev);
1363 if (!tzp || !tzp->tbp)
1366 for (i = 0; i < tzp->num_tbps; i++) {
1367 if (tzp->tbp[i].cdev == cdev) {
1368 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1369 tzp->tbp[i].cdev = NULL;
1374 mutex_unlock(&thermal_list_lock);
1376 cancel_delayed_work_sync(&tz->poll_queue);
1378 thermal_set_governor(tz, NULL);
1380 thermal_remove_hwmon_sysfs(tz);
1381 ida_simple_remove(&thermal_tz_ida, tz->id);
1382 ida_destroy(&tz->ida);
1383 mutex_destroy(&tz->lock);
1384 device_unregister(&tz->device);
1386 thermal_notify_tz_delete(tz_id);
1388 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1391 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1392 * @name: thermal zone name to fetch the temperature
1394 * When only one zone is found with the passed name, returns a reference to it.
1396 * Return: On success returns a reference to an unique thermal zone with
1397 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1398 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1400 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1402 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1403 unsigned int found = 0;
1408 mutex_lock(&thermal_list_lock);
1409 list_for_each_entry(pos, &thermal_tz_list, node)
1410 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1414 mutex_unlock(&thermal_list_lock);
1416 /* nothing has been found, thus an error code for it */
1418 ref = ERR_PTR(-ENODEV);
1420 /* Success only when an unique zone is found */
1421 ref = ERR_PTR(-EEXIST);
1426 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1428 static int thermal_pm_notify(struct notifier_block *nb,
1429 unsigned long mode, void *_unused)
1431 struct thermal_zone_device *tz;
1434 case PM_HIBERNATION_PREPARE:
1435 case PM_RESTORE_PREPARE:
1436 case PM_SUSPEND_PREPARE:
1437 atomic_set(&in_suspend, 1);
1439 case PM_POST_HIBERNATION:
1440 case PM_POST_RESTORE:
1441 case PM_POST_SUSPEND:
1442 atomic_set(&in_suspend, 0);
1443 list_for_each_entry(tz, &thermal_tz_list, node) {
1444 if (!thermal_zone_device_is_enabled(tz))
1447 thermal_zone_device_init(tz);
1448 thermal_zone_device_update(tz,
1449 THERMAL_EVENT_UNSPECIFIED);
1458 static struct notifier_block thermal_pm_nb = {
1459 .notifier_call = thermal_pm_notify,
1462 static int __init thermal_init(void)
1466 result = thermal_netlink_init();
1470 result = thermal_register_governors();
1474 result = class_register(&thermal_class);
1476 goto unregister_governors;
1478 result = of_parse_thermal_zones();
1480 goto unregister_class;
1482 result = register_pm_notifier(&thermal_pm_nb);
1484 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1490 class_unregister(&thermal_class);
1491 unregister_governors:
1492 thermal_unregister_governors();
1494 ida_destroy(&thermal_tz_ida);
1495 ida_destroy(&thermal_cdev_ida);
1496 mutex_destroy(&thermal_list_lock);
1497 mutex_destroy(&thermal_governor_lock);
1500 postcore_initcall(thermal_init);