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);
565 * thermal_notify_framework - Sensor drivers use this API to notify framework
566 * @tz: thermal zone device
567 * @trip: indicates which trip point has been crossed
569 * This function handles the trip events from sensor drivers. It starts
570 * throttling the cooling devices according to the policy configured.
571 * For CRITICAL and HOT trip points, this notifies the respective drivers,
572 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
573 * The throttling policy is based on the configured platform data; if no
574 * platform data is provided, this uses the step_wise throttling policy.
576 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
578 handle_thermal_trip(tz, trip);
580 EXPORT_SYMBOL_GPL(thermal_notify_framework);
582 static void thermal_zone_device_check(struct work_struct *work)
584 struct thermal_zone_device *tz = container_of(work, struct
587 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
590 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
593 struct thermal_governor *gov;
596 mutex_lock(&thermal_governor_lock);
597 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
602 mutex_unlock(&thermal_governor_lock);
607 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
610 struct thermal_cooling_device *cdev;
613 mutex_lock(&thermal_list_lock);
614 list_for_each_entry(cdev, &thermal_cdev_list, node) {
615 ret = cb(cdev, data);
619 mutex_unlock(&thermal_list_lock);
624 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
627 struct thermal_zone_device *tz;
630 mutex_lock(&thermal_list_lock);
631 list_for_each_entry(tz, &thermal_tz_list, node) {
636 mutex_unlock(&thermal_list_lock);
641 struct thermal_zone_device *thermal_zone_get_by_id(int id)
643 struct thermal_zone_device *tz, *match = NULL;
645 mutex_lock(&thermal_list_lock);
646 list_for_each_entry(tz, &thermal_tz_list, node) {
652 mutex_unlock(&thermal_list_lock);
658 * Device management section: cooling devices, zones devices, and binding
660 * Set of functions provided by the thermal core for:
661 * - cooling devices lifecycle: registration, unregistration,
662 * binding, and unbinding.
663 * - thermal zone devices lifecycle: registration, unregistration,
664 * binding, and unbinding.
668 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
669 * @tz: pointer to struct thermal_zone_device
670 * @trip: indicates which trip point the cooling devices is
671 * associated with in this thermal zone.
672 * @cdev: pointer to struct thermal_cooling_device
673 * @upper: the Maximum cooling state for this trip point.
674 * THERMAL_NO_LIMIT means no upper limit,
675 * and the cooling device can be in max_state.
676 * @lower: the Minimum cooling state can be used for this trip point.
677 * THERMAL_NO_LIMIT means no lower limit,
678 * and the cooling device can be in cooling state 0.
679 * @weight: The weight of the cooling device to be bound to the
680 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
683 * This interface function bind a thermal cooling device to the certain trip
684 * point of a thermal zone device.
685 * This function is usually called in the thermal zone device .bind callback.
687 * Return: 0 on success, the proper error value otherwise.
689 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
691 struct thermal_cooling_device *cdev,
692 unsigned long upper, unsigned long lower,
695 struct thermal_instance *dev;
696 struct thermal_instance *pos;
697 struct thermal_zone_device *pos1;
698 struct thermal_cooling_device *pos2;
699 unsigned long max_state;
702 if (trip >= tz->trips || trip < 0)
705 list_for_each_entry(pos1, &thermal_tz_list, node) {
709 list_for_each_entry(pos2, &thermal_cdev_list, node) {
714 if (tz != pos1 || cdev != pos2)
717 ret = cdev->ops->get_max_state(cdev, &max_state);
721 /* lower default 0, upper default max_state */
722 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
723 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
725 if (lower > upper || upper > max_state)
728 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
736 dev->target = THERMAL_NO_TARGET;
737 dev->weight = weight;
739 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
744 sprintf(dev->name, "cdev%d", dev->id);
746 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
750 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
751 sysfs_attr_init(&dev->attr.attr);
752 dev->attr.attr.name = dev->attr_name;
753 dev->attr.attr.mode = 0444;
754 dev->attr.show = trip_point_show;
755 result = device_create_file(&tz->device, &dev->attr);
757 goto remove_symbol_link;
759 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
760 sysfs_attr_init(&dev->weight_attr.attr);
761 dev->weight_attr.attr.name = dev->weight_attr_name;
762 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
763 dev->weight_attr.show = weight_show;
764 dev->weight_attr.store = weight_store;
765 result = device_create_file(&tz->device, &dev->weight_attr);
767 goto remove_trip_file;
769 mutex_lock(&tz->lock);
770 mutex_lock(&cdev->lock);
771 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
772 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
777 list_add_tail(&dev->tz_node, &tz->thermal_instances);
778 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
779 atomic_set(&tz->need_update, 1);
781 mutex_unlock(&cdev->lock);
782 mutex_unlock(&tz->lock);
787 device_remove_file(&tz->device, &dev->weight_attr);
789 device_remove_file(&tz->device, &dev->attr);
791 sysfs_remove_link(&tz->device.kobj, dev->name);
793 ida_simple_remove(&tz->ida, dev->id);
798 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
801 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
803 * @tz: pointer to a struct thermal_zone_device.
804 * @trip: indicates which trip point the cooling devices is
805 * associated with in this thermal zone.
806 * @cdev: pointer to a struct thermal_cooling_device.
808 * This interface function unbind a thermal cooling device from the certain
809 * trip point of a thermal zone device.
810 * This function is usually called in the thermal zone device .unbind callback.
812 * Return: 0 on success, the proper error value otherwise.
814 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
816 struct thermal_cooling_device *cdev)
818 struct thermal_instance *pos, *next;
820 mutex_lock(&tz->lock);
821 mutex_lock(&cdev->lock);
822 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
823 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
824 list_del(&pos->tz_node);
825 list_del(&pos->cdev_node);
826 mutex_unlock(&cdev->lock);
827 mutex_unlock(&tz->lock);
831 mutex_unlock(&cdev->lock);
832 mutex_unlock(&tz->lock);
837 device_remove_file(&tz->device, &pos->weight_attr);
838 device_remove_file(&tz->device, &pos->attr);
839 sysfs_remove_link(&tz->device.kobj, pos->name);
840 ida_simple_remove(&tz->ida, pos->id);
844 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
846 static void thermal_release(struct device *dev)
848 struct thermal_zone_device *tz;
849 struct thermal_cooling_device *cdev;
851 if (!strncmp(dev_name(dev), "thermal_zone",
852 sizeof("thermal_zone") - 1)) {
853 tz = to_thermal_zone(dev);
854 thermal_zone_destroy_device_groups(tz);
856 } else if (!strncmp(dev_name(dev), "cooling_device",
857 sizeof("cooling_device") - 1)) {
858 cdev = to_cooling_device(dev);
863 static struct class thermal_class = {
865 .dev_release = thermal_release,
869 void print_bind_err_msg(struct thermal_zone_device *tz,
870 struct thermal_cooling_device *cdev, int ret)
872 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
873 tz->type, cdev->type, ret);
876 static void __bind(struct thermal_zone_device *tz, int mask,
877 struct thermal_cooling_device *cdev,
878 unsigned long *limits,
883 for (i = 0; i < tz->trips; i++) {
884 if (mask & (1 << i)) {
885 unsigned long upper, lower;
887 upper = THERMAL_NO_LIMIT;
888 lower = THERMAL_NO_LIMIT;
890 lower = limits[i * 2];
891 upper = limits[i * 2 + 1];
893 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
897 print_bind_err_msg(tz, cdev, ret);
902 static void bind_cdev(struct thermal_cooling_device *cdev)
905 const struct thermal_zone_params *tzp;
906 struct thermal_zone_device *pos = NULL;
908 mutex_lock(&thermal_list_lock);
910 list_for_each_entry(pos, &thermal_tz_list, node) {
911 if (!pos->tzp && !pos->ops->bind)
914 if (pos->ops->bind) {
915 ret = pos->ops->bind(pos, cdev);
917 print_bind_err_msg(pos, cdev, ret);
922 if (!tzp || !tzp->tbp)
925 for (i = 0; i < tzp->num_tbps; i++) {
926 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
928 if (tzp->tbp[i].match(pos, cdev))
930 tzp->tbp[i].cdev = cdev;
931 __bind(pos, tzp->tbp[i].trip_mask, cdev,
932 tzp->tbp[i].binding_limits,
937 mutex_unlock(&thermal_list_lock);
941 * __thermal_cooling_device_register() - register a new thermal cooling device
942 * @np: a pointer to a device tree node.
943 * @type: the thermal cooling device type.
944 * @devdata: device private data.
945 * @ops: standard thermal cooling devices callbacks.
947 * This interface function adds a new thermal cooling device (fan/processor/...)
948 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
949 * to all the thermal zone devices registered at the same time.
950 * It also gives the opportunity to link the cooling device to a device tree
951 * node, so that it can be bound to a thermal zone created out of device tree.
953 * Return: a pointer to the created struct thermal_cooling_device or an
954 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
956 static struct thermal_cooling_device *
957 __thermal_cooling_device_register(struct device_node *np,
958 const char *type, void *devdata,
959 const struct thermal_cooling_device_ops *ops)
961 struct thermal_cooling_device *cdev;
962 struct thermal_zone_device *pos = NULL;
965 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
967 return ERR_PTR(-EINVAL);
969 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
971 return ERR_PTR(-ENOMEM);
973 ret = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
978 cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
984 mutex_init(&cdev->lock);
985 INIT_LIST_HEAD(&cdev->thermal_instances);
988 cdev->updated = false;
989 cdev->device.class = &thermal_class;
990 cdev->devdata = devdata;
991 thermal_cooling_device_setup_sysfs(cdev);
992 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
993 ret = device_register(&cdev->device);
997 /* Add 'this' new cdev to the global cdev list */
998 mutex_lock(&thermal_list_lock);
999 list_add(&cdev->node, &thermal_cdev_list);
1000 mutex_unlock(&thermal_list_lock);
1002 /* Update binding information for 'this' new cdev */
1005 mutex_lock(&thermal_list_lock);
1006 list_for_each_entry(pos, &thermal_tz_list, node)
1007 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1008 thermal_zone_device_update(pos,
1009 THERMAL_EVENT_UNSPECIFIED);
1010 mutex_unlock(&thermal_list_lock);
1016 put_device(&cdev->device);
1018 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1021 return ERR_PTR(ret);
1025 * thermal_cooling_device_register() - register a new thermal cooling device
1026 * @type: the thermal cooling device type.
1027 * @devdata: device private data.
1028 * @ops: standard thermal cooling devices callbacks.
1030 * This interface function adds a new thermal cooling device (fan/processor/...)
1031 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1032 * to all the thermal zone devices registered at the same time.
1034 * Return: a pointer to the created struct thermal_cooling_device or an
1035 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1037 struct thermal_cooling_device *
1038 thermal_cooling_device_register(const char *type, void *devdata,
1039 const struct thermal_cooling_device_ops *ops)
1041 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1043 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1046 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1047 * @np: a pointer to a device tree node.
1048 * @type: the thermal cooling device type.
1049 * @devdata: device private data.
1050 * @ops: standard thermal cooling devices callbacks.
1052 * This function will register a cooling device with device tree node reference.
1053 * This interface function adds a new thermal cooling device (fan/processor/...)
1054 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1055 * to all the thermal zone devices registered at the same time.
1057 * Return: a pointer to the created struct thermal_cooling_device or an
1058 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1060 struct thermal_cooling_device *
1061 thermal_of_cooling_device_register(struct device_node *np,
1062 const char *type, void *devdata,
1063 const struct thermal_cooling_device_ops *ops)
1065 return __thermal_cooling_device_register(np, type, devdata, ops);
1067 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1069 static void thermal_cooling_device_release(struct device *dev, void *res)
1071 thermal_cooling_device_unregister(
1072 *(struct thermal_cooling_device **)res);
1076 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1078 * @dev: a valid struct device pointer of a sensor device.
1079 * @np: a pointer to a device tree node.
1080 * @type: the thermal cooling device type.
1081 * @devdata: device private data.
1082 * @ops: standard thermal cooling devices callbacks.
1084 * This function will register a cooling device with device tree node reference.
1085 * This interface function adds a new thermal cooling device (fan/processor/...)
1086 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1087 * to all the thermal zone devices registered at the same time.
1089 * Return: a pointer to the created struct thermal_cooling_device or an
1090 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1092 struct thermal_cooling_device *
1093 devm_thermal_of_cooling_device_register(struct device *dev,
1094 struct device_node *np,
1095 char *type, void *devdata,
1096 const struct thermal_cooling_device_ops *ops)
1098 struct thermal_cooling_device **ptr, *tcd;
1100 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1103 return ERR_PTR(-ENOMEM);
1105 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1112 devres_add(dev, ptr);
1116 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1118 static void __unbind(struct thermal_zone_device *tz, int mask,
1119 struct thermal_cooling_device *cdev)
1123 for (i = 0; i < tz->trips; i++)
1124 if (mask & (1 << i))
1125 thermal_zone_unbind_cooling_device(tz, i, cdev);
1129 * thermal_cooling_device_unregister - removes a thermal cooling device
1130 * @cdev: the thermal cooling device to remove.
1132 * thermal_cooling_device_unregister() must be called when a registered
1133 * thermal cooling device is no longer needed.
1135 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1138 const struct thermal_zone_params *tzp;
1139 struct thermal_zone_device *tz;
1140 struct thermal_cooling_device *pos = NULL;
1145 mutex_lock(&thermal_list_lock);
1146 list_for_each_entry(pos, &thermal_cdev_list, node)
1150 /* thermal cooling device not found */
1151 mutex_unlock(&thermal_list_lock);
1154 list_del(&cdev->node);
1156 /* Unbind all thermal zones associated with 'this' cdev */
1157 list_for_each_entry(tz, &thermal_tz_list, node) {
1158 if (tz->ops->unbind) {
1159 tz->ops->unbind(tz, cdev);
1163 if (!tz->tzp || !tz->tzp->tbp)
1167 for (i = 0; i < tzp->num_tbps; i++) {
1168 if (tzp->tbp[i].cdev == cdev) {
1169 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1170 tzp->tbp[i].cdev = NULL;
1175 mutex_unlock(&thermal_list_lock);
1177 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1178 device_del(&cdev->device);
1179 thermal_cooling_device_destroy_sysfs(cdev);
1181 put_device(&cdev->device);
1183 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1185 static void bind_tz(struct thermal_zone_device *tz)
1188 struct thermal_cooling_device *pos = NULL;
1189 const struct thermal_zone_params *tzp = tz->tzp;
1191 if (!tzp && !tz->ops->bind)
1194 mutex_lock(&thermal_list_lock);
1196 /* If there is ops->bind, try to use ops->bind */
1197 if (tz->ops->bind) {
1198 list_for_each_entry(pos, &thermal_cdev_list, node) {
1199 ret = tz->ops->bind(tz, pos);
1201 print_bind_err_msg(tz, pos, ret);
1206 if (!tzp || !tzp->tbp)
1209 list_for_each_entry(pos, &thermal_cdev_list, node) {
1210 for (i = 0; i < tzp->num_tbps; i++) {
1211 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1213 if (tzp->tbp[i].match(tz, pos))
1215 tzp->tbp[i].cdev = pos;
1216 __bind(tz, tzp->tbp[i].trip_mask, pos,
1217 tzp->tbp[i].binding_limits,
1218 tzp->tbp[i].weight);
1222 mutex_unlock(&thermal_list_lock);
1226 * thermal_zone_device_register() - register a new thermal zone device
1227 * @type: the thermal zone device type
1228 * @trips: the number of trip points the thermal zone support
1229 * @mask: a bit string indicating the writeablility of trip points
1230 * @devdata: private device data
1231 * @ops: standard thermal zone device callbacks
1232 * @tzp: thermal zone platform parameters
1233 * @passive_delay: number of milliseconds to wait between polls when
1234 * performing passive cooling
1235 * @polling_delay: number of milliseconds to wait between polls when checking
1236 * whether trip points have been crossed (0 for interrupt
1239 * This interface function adds a new thermal zone device (sensor) to
1240 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1241 * thermal cooling devices registered at the same time.
1242 * thermal_zone_device_unregister() must be called when the device is no
1243 * longer needed. The passive cooling depends on the .get_trend() return value.
1245 * Return: a pointer to the created struct thermal_zone_device or an
1246 * in case of error, an ERR_PTR. Caller must check return value with
1247 * IS_ERR*() helpers.
1249 struct thermal_zone_device *
1250 thermal_zone_device_register(const char *type, int trips, int mask,
1251 void *devdata, struct thermal_zone_device_ops *ops,
1252 struct thermal_zone_params *tzp, int passive_delay,
1255 struct thermal_zone_device *tz;
1256 enum thermal_trip_type trip_type;
1261 struct thermal_governor *governor;
1263 if (!type || strlen(type) == 0) {
1264 pr_err("Error: No thermal zone type defined\n");
1265 return ERR_PTR(-EINVAL);
1268 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1269 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1270 type, THERMAL_NAME_LENGTH);
1271 return ERR_PTR(-EINVAL);
1274 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1275 pr_err("Error: Incorrect number of thermal trips\n");
1276 return ERR_PTR(-EINVAL);
1280 pr_err("Error: Thermal zone device ops not defined\n");
1281 return ERR_PTR(-EINVAL);
1284 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1285 return ERR_PTR(-EINVAL);
1287 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1289 return ERR_PTR(-ENOMEM);
1291 INIT_LIST_HEAD(&tz->thermal_instances);
1293 mutex_init(&tz->lock);
1294 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1301 strlcpy(tz->type, type, sizeof(tz->type));
1304 ops->critical = thermal_zone_device_critical;
1308 tz->device.class = &thermal_class;
1309 tz->devdata = devdata;
1312 thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1313 thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1316 /* Add nodes that are always present via .groups */
1317 result = thermal_zone_create_device_groups(tz, mask);
1321 /* A new thermal zone needs to be updated anyway. */
1322 atomic_set(&tz->need_update, 1);
1324 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1325 result = device_register(&tz->device);
1327 goto release_device;
1329 for (count = 0; count < trips; count++) {
1330 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1331 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1333 set_bit(count, &tz->trips_disabled);
1336 /* Update 'this' zone's governor information */
1337 mutex_lock(&thermal_governor_lock);
1340 governor = __find_governor(tz->tzp->governor_name);
1342 governor = def_governor;
1344 result = thermal_set_governor(tz, governor);
1346 mutex_unlock(&thermal_governor_lock);
1350 mutex_unlock(&thermal_governor_lock);
1352 if (!tz->tzp || !tz->tzp->no_hwmon) {
1353 result = thermal_add_hwmon_sysfs(tz);
1358 mutex_lock(&thermal_list_lock);
1359 list_add_tail(&tz->node, &thermal_tz_list);
1360 mutex_unlock(&thermal_list_lock);
1362 /* Bind cooling devices for this zone */
1365 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1367 thermal_zone_device_init(tz);
1368 /* Update the new thermal zone and mark it as already updated. */
1369 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1370 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1372 thermal_notify_tz_create(tz->id, tz->type);
1377 device_del(&tz->device);
1379 put_device(&tz->device);
1382 ida_simple_remove(&thermal_tz_ida, id);
1385 return ERR_PTR(result);
1387 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1390 * thermal_device_unregister - removes the registered thermal zone device
1391 * @tz: the thermal zone device to remove
1393 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1396 const struct thermal_zone_params *tzp;
1397 struct thermal_cooling_device *cdev;
1398 struct thermal_zone_device *pos = NULL;
1406 mutex_lock(&thermal_list_lock);
1407 list_for_each_entry(pos, &thermal_tz_list, node)
1411 /* thermal zone device not found */
1412 mutex_unlock(&thermal_list_lock);
1415 list_del(&tz->node);
1417 /* Unbind all cdevs associated with 'this' thermal zone */
1418 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1419 if (tz->ops->unbind) {
1420 tz->ops->unbind(tz, cdev);
1424 if (!tzp || !tzp->tbp)
1427 for (i = 0; i < tzp->num_tbps; i++) {
1428 if (tzp->tbp[i].cdev == cdev) {
1429 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1430 tzp->tbp[i].cdev = NULL;
1435 mutex_unlock(&thermal_list_lock);
1437 cancel_delayed_work_sync(&tz->poll_queue);
1439 thermal_set_governor(tz, NULL);
1441 thermal_remove_hwmon_sysfs(tz);
1442 ida_simple_remove(&thermal_tz_ida, tz->id);
1443 ida_destroy(&tz->ida);
1444 mutex_destroy(&tz->lock);
1445 device_unregister(&tz->device);
1447 thermal_notify_tz_delete(tz_id);
1449 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1452 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1453 * @name: thermal zone name to fetch the temperature
1455 * When only one zone is found with the passed name, returns a reference to it.
1457 * Return: On success returns a reference to an unique thermal zone with
1458 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1459 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1461 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1463 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1464 unsigned int found = 0;
1469 mutex_lock(&thermal_list_lock);
1470 list_for_each_entry(pos, &thermal_tz_list, node)
1471 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1475 mutex_unlock(&thermal_list_lock);
1477 /* nothing has been found, thus an error code for it */
1479 ref = ERR_PTR(-ENODEV);
1481 /* Success only when an unique zone is found */
1482 ref = ERR_PTR(-EEXIST);
1487 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1489 static int thermal_pm_notify(struct notifier_block *nb,
1490 unsigned long mode, void *_unused)
1492 struct thermal_zone_device *tz;
1495 case PM_HIBERNATION_PREPARE:
1496 case PM_RESTORE_PREPARE:
1497 case PM_SUSPEND_PREPARE:
1498 atomic_set(&in_suspend, 1);
1500 case PM_POST_HIBERNATION:
1501 case PM_POST_RESTORE:
1502 case PM_POST_SUSPEND:
1503 atomic_set(&in_suspend, 0);
1504 list_for_each_entry(tz, &thermal_tz_list, node) {
1505 if (!thermal_zone_device_is_enabled(tz))
1508 thermal_zone_device_init(tz);
1509 thermal_zone_device_update(tz,
1510 THERMAL_EVENT_UNSPECIFIED);
1519 static struct notifier_block thermal_pm_nb = {
1520 .notifier_call = thermal_pm_notify,
1523 static int __init thermal_init(void)
1527 result = thermal_netlink_init();
1531 result = thermal_register_governors();
1535 result = class_register(&thermal_class);
1537 goto unregister_governors;
1539 result = of_parse_thermal_zones();
1541 goto unregister_class;
1543 result = register_pm_notifier(&thermal_pm_nb);
1545 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1551 class_unregister(&thermal_class);
1552 unregister_governors:
1553 thermal_unregister_governors();
1555 ida_destroy(&thermal_tz_ida);
1556 ida_destroy(&thermal_cdev_ida);
1557 mutex_destroy(&thermal_list_lock);
1558 mutex_destroy(&thermal_governor_lock);
1559 mutex_destroy(&poweroff_lock);
1562 postcore_initcall(thermal_init);