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 "thermal_trace.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 if (!device_is_registered(&tz->device))
209 gov = __find_governor(strim(policy));
213 ret = thermal_set_governor(tz, gov);
216 mutex_unlock(&tz->lock);
217 mutex_unlock(&thermal_governor_lock);
219 thermal_notify_tz_gov_change(tz->id, policy);
224 int thermal_build_list_of_policies(char *buf)
226 struct thermal_governor *pos;
229 mutex_lock(&thermal_governor_lock);
231 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
232 count += sysfs_emit_at(buf, count, "%s ", pos->name);
234 count += sysfs_emit_at(buf, count, "\n");
236 mutex_unlock(&thermal_governor_lock);
241 static void __init thermal_unregister_governors(void)
243 struct thermal_governor **governor;
245 for_each_governor_table(governor)
246 thermal_unregister_governor(*governor);
249 static int __init thermal_register_governors(void)
252 struct thermal_governor **governor;
254 for_each_governor_table(governor) {
255 ret = thermal_register_governor(*governor);
257 pr_err("Failed to register governor: '%s'",
262 pr_info("Registered thermal governor '%s'",
267 struct thermal_governor **gov;
269 for_each_governor_table(gov) {
272 thermal_unregister_governor(*gov);
280 * Zone update section: main control loop applied to each zone while monitoring
282 * in polling mode. The monitoring is done using a workqueue.
283 * Same update may be done on a zone by calling thermal_zone_device_update().
286 * - Non-critical trips will invoke the governor responsible for that zone;
287 * - Hot trips will produce a notification to userspace;
288 * - Critical trip point will cause a system shutdown.
290 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
294 mod_delayed_work(system_freezable_power_efficient_wq,
295 &tz->poll_queue, delay);
297 cancel_delayed_work(&tz->poll_queue);
300 static void monitor_thermal_zone(struct thermal_zone_device *tz)
302 if (tz->mode != THERMAL_DEVICE_ENABLED)
303 thermal_zone_device_set_polling(tz, 0);
304 else if (tz->passive)
305 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
306 else if (tz->polling_delay_jiffies)
307 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
310 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
312 tz->governor ? tz->governor->throttle(tz, trip) :
313 def_governor->throttle(tz, trip);
316 void thermal_zone_device_critical(struct thermal_zone_device *tz)
319 * poweroff_delay_ms must be a carefully profiled positive value.
320 * Its a must for forced_emergency_poweroff_work to be scheduled.
322 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
324 dev_emerg(&tz->device, "%s: critical temperature reached, "
325 "shutting down\n", tz->type);
327 hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
329 EXPORT_SYMBOL(thermal_zone_device_critical);
331 static void handle_critical_trips(struct thermal_zone_device *tz,
332 int trip, int trip_temp, enum thermal_trip_type trip_type)
334 /* If we have not crossed the trip_temp, we do not care. */
335 if (trip_temp <= 0 || tz->temperature < trip_temp)
338 trace_thermal_zone_trip(tz, trip, trip_type);
340 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
342 else if (trip_type == THERMAL_TRIP_CRITICAL)
343 tz->ops->critical(tz);
346 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip_id)
348 struct thermal_trip trip;
350 /* Ignore disabled trip points */
351 if (test_bit(trip_id, &tz->trips_disabled) ||
352 trip.temperature == THERMAL_TEMP_INVALID)
355 __thermal_zone_get_trip(tz, trip_id, &trip);
357 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
358 if (tz->last_temperature < trip.temperature &&
359 tz->temperature >= trip.temperature)
360 thermal_notify_tz_trip_up(tz->id, trip_id,
362 if (tz->last_temperature >= trip.temperature &&
363 tz->temperature < (trip.temperature - trip.hysteresis))
364 thermal_notify_tz_trip_down(tz->id, trip_id,
368 if (trip.type == THERMAL_TRIP_CRITICAL || trip.type == THERMAL_TRIP_HOT)
369 handle_critical_trips(tz, trip_id, trip.temperature, trip.type);
371 handle_non_critical_trips(tz, trip_id);
374 static void update_temperature(struct thermal_zone_device *tz)
378 ret = __thermal_zone_get_temp(tz, &temp);
381 dev_warn(&tz->device,
382 "failed to read out thermal zone (%d)\n",
387 tz->last_temperature = tz->temperature;
388 tz->temperature = temp;
390 trace_thermal_temperature(tz);
392 thermal_genl_sampling_temp(tz->id, temp);
395 static void thermal_zone_device_init(struct thermal_zone_device *tz)
397 struct thermal_instance *pos;
398 tz->temperature = THERMAL_TEMP_INVALID;
399 tz->prev_low_trip = -INT_MAX;
400 tz->prev_high_trip = INT_MAX;
401 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
402 pos->initialized = false;
405 void __thermal_zone_device_update(struct thermal_zone_device *tz,
406 enum thermal_notify_event event)
410 if (atomic_read(&in_suspend))
413 if (WARN_ONCE(!tz->ops->get_temp,
414 "'%s' must not be called without 'get_temp' ops set\n",
418 if (!thermal_zone_device_is_enabled(tz))
421 update_temperature(tz);
423 __thermal_zone_set_trips(tz);
425 tz->notify_event = event;
427 for (count = 0; count < tz->num_trips; count++)
428 handle_thermal_trip(tz, count);
430 monitor_thermal_zone(tz);
433 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
434 enum thermal_device_mode mode)
438 mutex_lock(&tz->lock);
440 /* do nothing if mode isn't changing */
441 if (mode == tz->mode) {
442 mutex_unlock(&tz->lock);
447 if (!device_is_registered(&tz->device)) {
448 mutex_unlock(&tz->lock);
453 if (tz->ops->change_mode)
454 ret = tz->ops->change_mode(tz, mode);
459 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
461 mutex_unlock(&tz->lock);
463 if (mode == THERMAL_DEVICE_ENABLED)
464 thermal_notify_tz_enable(tz->id);
466 thermal_notify_tz_disable(tz->id);
471 int thermal_zone_device_enable(struct thermal_zone_device *tz)
473 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
475 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
477 int thermal_zone_device_disable(struct thermal_zone_device *tz)
479 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
481 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
483 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
485 lockdep_assert_held(&tz->lock);
487 return tz->mode == THERMAL_DEVICE_ENABLED;
490 void thermal_zone_device_update(struct thermal_zone_device *tz,
491 enum thermal_notify_event event)
493 mutex_lock(&tz->lock);
494 if (device_is_registered(&tz->device))
495 __thermal_zone_device_update(tz, event);
496 mutex_unlock(&tz->lock);
498 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
501 * thermal_zone_device_exec - Run a callback under the zone lock.
503 * @cb: Callback to run.
504 * @data: Data to pass to the callback.
506 void thermal_zone_device_exec(struct thermal_zone_device *tz,
507 void (*cb)(struct thermal_zone_device *,
511 mutex_lock(&tz->lock);
515 mutex_unlock(&tz->lock);
517 EXPORT_SYMBOL_GPL(thermal_zone_device_exec);
519 static void thermal_zone_device_check(struct work_struct *work)
521 struct thermal_zone_device *tz = container_of(work, struct
524 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
527 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
530 struct thermal_governor *gov;
533 mutex_lock(&thermal_governor_lock);
534 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
539 mutex_unlock(&thermal_governor_lock);
544 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
547 struct thermal_cooling_device *cdev;
550 mutex_lock(&thermal_list_lock);
551 list_for_each_entry(cdev, &thermal_cdev_list, node) {
552 ret = cb(cdev, data);
556 mutex_unlock(&thermal_list_lock);
561 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
564 struct thermal_zone_device *tz;
567 mutex_lock(&thermal_list_lock);
568 list_for_each_entry(tz, &thermal_tz_list, node) {
573 mutex_unlock(&thermal_list_lock);
578 struct thermal_zone_device *thermal_zone_get_by_id(int id)
580 struct thermal_zone_device *tz, *match = NULL;
582 mutex_lock(&thermal_list_lock);
583 list_for_each_entry(tz, &thermal_tz_list, node) {
589 mutex_unlock(&thermal_list_lock);
595 * Device management section: cooling devices, zones devices, and binding
597 * Set of functions provided by the thermal core for:
598 * - cooling devices lifecycle: registration, unregistration,
599 * binding, and unbinding.
600 * - thermal zone devices lifecycle: registration, unregistration,
601 * binding, and unbinding.
605 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
606 * @tz: pointer to struct thermal_zone_device
607 * @trip: indicates which trip point the cooling devices is
608 * associated with in this thermal zone.
609 * @cdev: pointer to struct thermal_cooling_device
610 * @upper: the Maximum cooling state for this trip point.
611 * THERMAL_NO_LIMIT means no upper limit,
612 * and the cooling device can be in max_state.
613 * @lower: the Minimum cooling state can be used for this trip point.
614 * THERMAL_NO_LIMIT means no lower limit,
615 * and the cooling device can be in cooling state 0.
616 * @weight: The weight of the cooling device to be bound to the
617 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
620 * This interface function bind a thermal cooling device to the certain trip
621 * point of a thermal zone device.
622 * This function is usually called in the thermal zone device .bind callback.
624 * Return: 0 on success, the proper error value otherwise.
626 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
628 struct thermal_cooling_device *cdev,
629 unsigned long upper, unsigned long lower,
632 struct thermal_instance *dev;
633 struct thermal_instance *pos;
634 struct thermal_zone_device *pos1;
635 struct thermal_cooling_device *pos2;
639 if (trip >= tz->num_trips || trip < 0)
642 list_for_each_entry(pos1, &thermal_tz_list, node) {
646 list_for_each_entry(pos2, &thermal_cdev_list, node) {
651 if (tz != pos1 || cdev != pos2)
654 /* lower default 0, upper default max_state */
655 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
657 if (upper == THERMAL_NO_LIMIT) {
658 upper = cdev->max_state;
659 upper_no_limit = true;
661 upper_no_limit = false;
664 if (lower > upper || upper > cdev->max_state)
667 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
674 dev->upper_no_limit = upper_no_limit;
676 dev->target = THERMAL_NO_TARGET;
677 dev->weight = weight;
679 result = ida_alloc(&tz->ida, GFP_KERNEL);
684 sprintf(dev->name, "cdev%d", dev->id);
686 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
690 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
691 sysfs_attr_init(&dev->attr.attr);
692 dev->attr.attr.name = dev->attr_name;
693 dev->attr.attr.mode = 0444;
694 dev->attr.show = trip_point_show;
695 result = device_create_file(&tz->device, &dev->attr);
697 goto remove_symbol_link;
699 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
700 sysfs_attr_init(&dev->weight_attr.attr);
701 dev->weight_attr.attr.name = dev->weight_attr_name;
702 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
703 dev->weight_attr.show = weight_show;
704 dev->weight_attr.store = weight_store;
705 result = device_create_file(&tz->device, &dev->weight_attr);
707 goto remove_trip_file;
709 mutex_lock(&tz->lock);
710 mutex_lock(&cdev->lock);
711 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
712 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
717 list_add_tail(&dev->tz_node, &tz->thermal_instances);
718 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
719 atomic_set(&tz->need_update, 1);
721 mutex_unlock(&cdev->lock);
722 mutex_unlock(&tz->lock);
727 device_remove_file(&tz->device, &dev->weight_attr);
729 device_remove_file(&tz->device, &dev->attr);
731 sysfs_remove_link(&tz->device.kobj, dev->name);
733 ida_free(&tz->ida, dev->id);
738 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
741 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
743 * @tz: pointer to a struct thermal_zone_device.
744 * @trip: indicates which trip point the cooling devices is
745 * associated with in this thermal zone.
746 * @cdev: pointer to a struct thermal_cooling_device.
748 * This interface function unbind a thermal cooling device from the certain
749 * trip point of a thermal zone device.
750 * This function is usually called in the thermal zone device .unbind callback.
752 * Return: 0 on success, the proper error value otherwise.
754 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
756 struct thermal_cooling_device *cdev)
758 struct thermal_instance *pos, *next;
760 mutex_lock(&tz->lock);
761 mutex_lock(&cdev->lock);
762 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
763 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
764 list_del(&pos->tz_node);
765 list_del(&pos->cdev_node);
766 mutex_unlock(&cdev->lock);
767 mutex_unlock(&tz->lock);
771 mutex_unlock(&cdev->lock);
772 mutex_unlock(&tz->lock);
777 device_remove_file(&tz->device, &pos->weight_attr);
778 device_remove_file(&tz->device, &pos->attr);
779 sysfs_remove_link(&tz->device.kobj, pos->name);
780 ida_free(&tz->ida, pos->id);
784 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
786 static void thermal_release(struct device *dev)
788 struct thermal_zone_device *tz;
789 struct thermal_cooling_device *cdev;
791 if (!strncmp(dev_name(dev), "thermal_zone",
792 sizeof("thermal_zone") - 1)) {
793 tz = to_thermal_zone(dev);
794 thermal_zone_destroy_device_groups(tz);
795 mutex_destroy(&tz->lock);
797 } else if (!strncmp(dev_name(dev), "cooling_device",
798 sizeof("cooling_device") - 1)) {
799 cdev = to_cooling_device(dev);
800 thermal_cooling_device_destroy_sysfs(cdev);
802 ida_free(&thermal_cdev_ida, cdev->id);
807 static struct class *thermal_class;
810 void print_bind_err_msg(struct thermal_zone_device *tz,
811 struct thermal_cooling_device *cdev, int ret)
813 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
814 tz->type, cdev->type, ret);
817 static void bind_cdev(struct thermal_cooling_device *cdev)
820 struct thermal_zone_device *pos = NULL;
822 list_for_each_entry(pos, &thermal_tz_list, node) {
823 if (pos->ops->bind) {
824 ret = pos->ops->bind(pos, cdev);
826 print_bind_err_msg(pos, cdev, ret);
832 * __thermal_cooling_device_register() - register a new thermal cooling device
833 * @np: a pointer to a device tree node.
834 * @type: the thermal cooling device type.
835 * @devdata: device private data.
836 * @ops: standard thermal cooling devices callbacks.
838 * This interface function adds a new thermal cooling device (fan/processor/...)
839 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
840 * to all the thermal zone devices registered at the same time.
841 * It also gives the opportunity to link the cooling device to a device tree
842 * node, so that it can be bound to a thermal zone created out of device tree.
844 * Return: a pointer to the created struct thermal_cooling_device or an
845 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
847 static struct thermal_cooling_device *
848 __thermal_cooling_device_register(struct device_node *np,
849 const char *type, void *devdata,
850 const struct thermal_cooling_device_ops *ops)
852 struct thermal_cooling_device *cdev;
853 struct thermal_zone_device *pos = NULL;
856 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
858 return ERR_PTR(-EINVAL);
861 return ERR_PTR(-ENODEV);
863 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
865 return ERR_PTR(-ENOMEM);
867 ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
873 cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
879 mutex_init(&cdev->lock);
880 INIT_LIST_HEAD(&cdev->thermal_instances);
883 cdev->updated = false;
884 cdev->device.class = thermal_class;
885 cdev->devdata = devdata;
887 ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
891 thermal_cooling_device_setup_sysfs(cdev);
893 ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
895 goto out_cooling_dev;
897 ret = device_register(&cdev->device);
899 /* thermal_release() handles rest of the cleanup */
900 put_device(&cdev->device);
904 /* Add 'this' new cdev to the global cdev list */
905 mutex_lock(&thermal_list_lock);
907 list_add(&cdev->node, &thermal_cdev_list);
909 /* Update binding information for 'this' new cdev */
912 list_for_each_entry(pos, &thermal_tz_list, node)
913 if (atomic_cmpxchg(&pos->need_update, 1, 0))
914 thermal_zone_device_update(pos,
915 THERMAL_EVENT_UNSPECIFIED);
917 mutex_unlock(&thermal_list_lock);
922 thermal_cooling_device_destroy_sysfs(cdev);
926 ida_free(&thermal_cdev_ida, id);
933 * thermal_cooling_device_register() - register a new thermal cooling device
934 * @type: the thermal cooling device type.
935 * @devdata: device private data.
936 * @ops: standard thermal cooling devices callbacks.
938 * This interface function adds a new thermal cooling device (fan/processor/...)
939 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
940 * to all the thermal zone devices registered at the same time.
942 * Return: a pointer to the created struct thermal_cooling_device or an
943 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
945 struct thermal_cooling_device *
946 thermal_cooling_device_register(const char *type, void *devdata,
947 const struct thermal_cooling_device_ops *ops)
949 return __thermal_cooling_device_register(NULL, type, devdata, ops);
951 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
954 * thermal_of_cooling_device_register() - register an OF thermal cooling device
955 * @np: a pointer to a device tree node.
956 * @type: the thermal cooling device type.
957 * @devdata: device private data.
958 * @ops: standard thermal cooling devices callbacks.
960 * This function will register a cooling device with device tree node reference.
961 * This interface function adds a new thermal cooling device (fan/processor/...)
962 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
963 * to all the thermal zone devices registered at the same time.
965 * Return: a pointer to the created struct thermal_cooling_device or an
966 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
968 struct thermal_cooling_device *
969 thermal_of_cooling_device_register(struct device_node *np,
970 const char *type, void *devdata,
971 const struct thermal_cooling_device_ops *ops)
973 return __thermal_cooling_device_register(np, type, devdata, ops);
975 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
977 static void thermal_cooling_device_release(struct device *dev, void *res)
979 thermal_cooling_device_unregister(
980 *(struct thermal_cooling_device **)res);
984 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
986 * @dev: a valid struct device pointer of a sensor device.
987 * @np: a pointer to a device tree node.
988 * @type: the thermal cooling device type.
989 * @devdata: device private data.
990 * @ops: standard thermal cooling devices callbacks.
992 * This function will register a cooling device with device tree node reference.
993 * This interface function adds a new thermal cooling device (fan/processor/...)
994 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
995 * to all the thermal zone devices registered at the same time.
997 * Return: a pointer to the created struct thermal_cooling_device or an
998 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1000 struct thermal_cooling_device *
1001 devm_thermal_of_cooling_device_register(struct device *dev,
1002 struct device_node *np,
1003 char *type, void *devdata,
1004 const struct thermal_cooling_device_ops *ops)
1006 struct thermal_cooling_device **ptr, *tcd;
1008 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1011 return ERR_PTR(-ENOMEM);
1013 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1020 devres_add(dev, ptr);
1024 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1026 static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1028 struct thermal_cooling_device *pos = NULL;
1030 list_for_each_entry(pos, &thermal_cdev_list, node) {
1039 * thermal_cooling_device_update - Update a cooling device object
1040 * @cdev: Target cooling device.
1042 * Update @cdev to reflect a change of the underlying hardware or platform.
1044 * Must be called when the maximum cooling state of @cdev becomes invalid and so
1045 * its .get_max_state() callback needs to be run to produce the new maximum
1046 * cooling state value.
1048 void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1050 struct thermal_instance *ti;
1051 unsigned long state;
1053 if (IS_ERR_OR_NULL(cdev))
1057 * Hold thermal_list_lock throughout the update to prevent the device
1058 * from going away while being updated.
1060 mutex_lock(&thermal_list_lock);
1062 if (!thermal_cooling_device_present(cdev))
1066 * Update under the cdev lock to prevent the state from being set beyond
1067 * the new limit concurrently.
1069 mutex_lock(&cdev->lock);
1071 if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1074 thermal_cooling_device_stats_reinit(cdev);
1076 list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1077 if (ti->upper == cdev->max_state)
1080 if (ti->upper < cdev->max_state) {
1081 if (ti->upper_no_limit)
1082 ti->upper = cdev->max_state;
1087 ti->upper = cdev->max_state;
1088 if (ti->lower > ti->upper)
1089 ti->lower = ti->upper;
1091 if (ti->target == THERMAL_NO_TARGET)
1094 if (ti->target > ti->upper)
1095 ti->target = ti->upper;
1098 if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1101 thermal_cooling_device_stats_update(cdev, state);
1104 mutex_unlock(&cdev->lock);
1107 mutex_unlock(&thermal_list_lock);
1109 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1112 * thermal_cooling_device_unregister - removes a thermal cooling device
1113 * @cdev: the thermal cooling device to remove.
1115 * thermal_cooling_device_unregister() must be called when a registered
1116 * thermal cooling device is no longer needed.
1118 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1120 struct thermal_zone_device *tz;
1125 mutex_lock(&thermal_list_lock);
1127 if (!thermal_cooling_device_present(cdev)) {
1128 mutex_unlock(&thermal_list_lock);
1132 list_del(&cdev->node);
1134 /* Unbind all thermal zones associated with 'this' cdev */
1135 list_for_each_entry(tz, &thermal_tz_list, node) {
1136 if (tz->ops->unbind)
1137 tz->ops->unbind(tz, cdev);
1140 mutex_unlock(&thermal_list_lock);
1142 device_unregister(&cdev->device);
1144 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1146 static void bind_tz(struct thermal_zone_device *tz)
1149 struct thermal_cooling_device *pos = NULL;
1154 mutex_lock(&thermal_list_lock);
1156 list_for_each_entry(pos, &thermal_cdev_list, node) {
1157 ret = tz->ops->bind(tz, pos);
1159 print_bind_err_msg(tz, pos, ret);
1162 mutex_unlock(&thermal_list_lock);
1165 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1167 *delay_jiffies = msecs_to_jiffies(delay_ms);
1168 if (delay_ms > 1000)
1169 *delay_jiffies = round_jiffies(*delay_jiffies);
1172 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1174 int i, ret = -EINVAL;
1176 if (tz->ops->get_crit_temp)
1177 return tz->ops->get_crit_temp(tz, temp);
1182 mutex_lock(&tz->lock);
1184 for (i = 0; i < tz->num_trips; i++) {
1185 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1186 *temp = tz->trips[i].temperature;
1192 mutex_unlock(&tz->lock);
1196 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1199 * thermal_zone_device_register_with_trips() - register a new thermal zone device
1200 * @type: the thermal zone device type
1201 * @trips: a pointer to an array of thermal trips
1202 * @num_trips: the number of trip points the thermal zone support
1203 * @mask: a bit string indicating the writeablility of trip points
1204 * @devdata: private device data
1205 * @ops: standard thermal zone device callbacks
1206 * @tzp: thermal zone platform parameters
1207 * @passive_delay: number of milliseconds to wait between polls when
1208 * performing passive cooling
1209 * @polling_delay: number of milliseconds to wait between polls when checking
1210 * whether trip points have been crossed (0 for interrupt
1213 * This interface function adds a new thermal zone device (sensor) to
1214 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1215 * thermal cooling devices registered at the same time.
1216 * thermal_zone_device_unregister() must be called when the device is no
1217 * longer needed. The passive cooling depends on the .get_trend() return value.
1219 * Return: a pointer to the created struct thermal_zone_device or an
1220 * in case of error, an ERR_PTR. Caller must check return value with
1221 * IS_ERR*() helpers.
1223 struct thermal_zone_device *
1224 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1225 void *devdata, struct thermal_zone_device_ops *ops,
1226 const struct thermal_zone_params *tzp, int passive_delay,
1229 struct thermal_zone_device *tz;
1233 struct thermal_governor *governor;
1235 if (!type || strlen(type) == 0) {
1236 pr_err("No thermal zone type defined\n");
1237 return ERR_PTR(-EINVAL);
1240 if (strlen(type) >= THERMAL_NAME_LENGTH) {
1241 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1242 type, THERMAL_NAME_LENGTH);
1243 return ERR_PTR(-EINVAL);
1247 * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1248 * For example, shifting by 32 will result in compiler warning:
1249 * warning: right shift count >= width of type [-Wshift-count- overflow]
1251 * Also "mask >> num_trips" will always be true with 32 bit shift.
1252 * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1253 * mask >> 32 = 0x80000000
1254 * This will result in failure for the below condition.
1256 * Check will be true when the bit 31 of the mask is set.
1257 * 32 bit shift will cause overflow of 4 byte integer.
1259 if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1260 pr_err("Incorrect number of thermal trips\n");
1261 return ERR_PTR(-EINVAL);
1265 pr_err("Thermal zone device ops not defined\n");
1266 return ERR_PTR(-EINVAL);
1269 if (num_trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp) && !trips)
1270 return ERR_PTR(-EINVAL);
1273 return ERR_PTR(-ENODEV);
1275 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1277 return ERR_PTR(-ENOMEM);
1280 tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1287 INIT_LIST_HEAD(&tz->thermal_instances);
1289 mutex_init(&tz->lock);
1290 id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1297 strscpy(tz->type, type, sizeof(tz->type));
1300 ops->critical = thermal_zone_device_critical;
1303 tz->device.class = thermal_class;
1304 tz->devdata = devdata;
1306 tz->num_trips = num_trips;
1308 thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1309 thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1312 /* Add nodes that are always present via .groups */
1313 result = thermal_zone_create_device_groups(tz, mask);
1317 /* A new thermal zone needs to be updated anyway. */
1318 atomic_set(&tz->need_update, 1);
1320 result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1322 thermal_zone_destroy_device_groups(tz);
1325 result = device_register(&tz->device);
1327 goto release_device;
1329 for (count = 0; count < num_trips; count++) {
1330 struct thermal_trip trip;
1332 result = thermal_zone_get_trip(tz, count, &trip);
1333 if (result || !trip.temperature)
1334 set_bit(count, &tz->trips_disabled);
1337 /* Update 'this' zone's governor information */
1338 mutex_lock(&thermal_governor_lock);
1341 governor = __find_governor(tz->tzp->governor_name);
1343 governor = def_governor;
1345 result = thermal_set_governor(tz, governor);
1347 mutex_unlock(&thermal_governor_lock);
1351 mutex_unlock(&thermal_governor_lock);
1353 if (!tz->tzp || !tz->tzp->no_hwmon) {
1354 result = thermal_add_hwmon_sysfs(tz);
1359 mutex_lock(&thermal_list_lock);
1360 list_add_tail(&tz->node, &thermal_tz_list);
1361 mutex_unlock(&thermal_list_lock);
1363 /* Bind cooling devices for this zone */
1366 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1368 thermal_zone_device_init(tz);
1369 /* Update the new thermal zone and mark it as already updated. */
1370 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1371 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1373 thermal_notify_tz_create(tz->id, tz->type);
1378 device_del(&tz->device);
1380 put_device(&tz->device);
1383 ida_free(&thermal_tz_ida, id);
1388 return ERR_PTR(result);
1390 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1392 struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
1393 void *devdata, struct thermal_zone_device_ops *ops,
1394 const struct thermal_zone_params *tzp, int passive_delay,
1397 return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
1399 passive_delay, polling_delay);
1401 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1403 void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1405 return tzd->devdata;
1407 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1409 const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1413 EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1415 int thermal_zone_device_id(struct thermal_zone_device *tzd)
1419 EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1421 struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1423 return &tzd->device;
1425 EXPORT_SYMBOL_GPL(thermal_zone_device);
1428 * thermal_zone_device_unregister - removes the registered thermal zone device
1429 * @tz: the thermal zone device to remove
1431 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1434 struct thermal_cooling_device *cdev;
1435 struct thermal_zone_device *pos = NULL;
1442 mutex_lock(&thermal_list_lock);
1443 list_for_each_entry(pos, &thermal_tz_list, node)
1447 /* thermal zone device not found */
1448 mutex_unlock(&thermal_list_lock);
1451 list_del(&tz->node);
1453 /* Unbind all cdevs associated with 'this' thermal zone */
1454 list_for_each_entry(cdev, &thermal_cdev_list, node)
1455 if (tz->ops->unbind)
1456 tz->ops->unbind(tz, cdev);
1458 mutex_unlock(&thermal_list_lock);
1460 cancel_delayed_work_sync(&tz->poll_queue);
1462 thermal_set_governor(tz, NULL);
1464 thermal_remove_hwmon_sysfs(tz);
1465 ida_free(&thermal_tz_ida, tz->id);
1466 ida_destroy(&tz->ida);
1468 mutex_lock(&tz->lock);
1469 device_del(&tz->device);
1470 mutex_unlock(&tz->lock);
1474 put_device(&tz->device);
1476 thermal_notify_tz_delete(tz_id);
1478 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1481 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1482 * @name: thermal zone name to fetch the temperature
1484 * When only one zone is found with the passed name, returns a reference to it.
1486 * Return: On success returns a reference to an unique thermal zone with
1487 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1488 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1490 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1492 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1493 unsigned int found = 0;
1498 mutex_lock(&thermal_list_lock);
1499 list_for_each_entry(pos, &thermal_tz_list, node)
1500 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1504 mutex_unlock(&thermal_list_lock);
1506 /* nothing has been found, thus an error code for it */
1508 ref = ERR_PTR(-ENODEV);
1510 /* Success only when an unique zone is found */
1511 ref = ERR_PTR(-EEXIST);
1516 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1518 static int thermal_pm_notify(struct notifier_block *nb,
1519 unsigned long mode, void *_unused)
1521 struct thermal_zone_device *tz;
1524 case PM_HIBERNATION_PREPARE:
1525 case PM_RESTORE_PREPARE:
1526 case PM_SUSPEND_PREPARE:
1527 atomic_set(&in_suspend, 1);
1529 case PM_POST_HIBERNATION:
1530 case PM_POST_RESTORE:
1531 case PM_POST_SUSPEND:
1532 atomic_set(&in_suspend, 0);
1533 list_for_each_entry(tz, &thermal_tz_list, node) {
1534 thermal_zone_device_init(tz);
1535 thermal_zone_device_update(tz,
1536 THERMAL_EVENT_UNSPECIFIED);
1545 static struct notifier_block thermal_pm_nb = {
1546 .notifier_call = thermal_pm_notify,
1549 static int __init thermal_init(void)
1553 result = thermal_netlink_init();
1557 result = thermal_register_governors();
1559 goto unregister_netlink;
1561 thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1562 if (!thermal_class) {
1564 goto unregister_governors;
1567 thermal_class->name = "thermal";
1568 thermal_class->dev_release = thermal_release;
1570 result = class_register(thermal_class);
1572 kfree(thermal_class);
1573 thermal_class = NULL;
1574 goto unregister_governors;
1577 result = register_pm_notifier(&thermal_pm_nb);
1579 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1584 unregister_governors:
1585 thermal_unregister_governors();
1587 thermal_netlink_exit();
1589 mutex_destroy(&thermal_list_lock);
1590 mutex_destroy(&thermal_governor_lock);
1593 postcore_initcall(thermal_init);