Merge tag 'trace-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
[linux/fpc-iii.git] / drivers / thermal / thermal_core.c
blob4a291d205d5c042adadce8fc2c55d26c2adc458a
1 // SPDX-License-Identifier: GPL-2.0
2 /*
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>
8 */
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>
21 #include <linux/of.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])
58 return def_governor;
60 list_for_each_entry(pos, &thermal_governor_list, governor_list)
61 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
62 return pos;
64 return NULL;
67 /**
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)) {
80 dev_err(&tz->device,
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);
83 tz->governor = NULL;
88 /**
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)
100 int ret = 0;
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);
107 if (ret) {
108 bind_previous_governor(tz, new_gov->name);
110 return ret;
114 tz->governor = new_gov;
116 return ret;
119 int thermal_register_governor(struct thermal_governor *governor)
121 int err;
122 const char *name;
123 struct thermal_zone_device *pos;
125 if (!governor)
126 return -EINVAL;
128 mutex_lock(&thermal_governor_lock);
130 err = -EBUSY;
131 if (!__find_governor(governor->name)) {
132 bool match_default;
134 err = 0;
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
151 if (pos->governor)
152 continue;
154 name = pos->tzp->governor_name;
156 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
157 int ret;
159 ret = thermal_set_governor(pos, governor);
160 if (ret)
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);
170 return err;
173 void thermal_unregister_governor(struct thermal_governor *governor)
175 struct thermal_zone_device *pos;
177 if (!governor)
178 return;
180 mutex_lock(&thermal_governor_lock);
182 if (!__find_governor(governor->name))
183 goto exit;
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);
195 exit:
196 mutex_unlock(&thermal_governor_lock);
199 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
200 char *policy)
202 struct thermal_governor *gov;
203 int ret = -EINVAL;
205 mutex_lock(&thermal_governor_lock);
206 mutex_lock(&tz->lock);
208 gov = __find_governor(strim(policy));
209 if (!gov)
210 goto exit;
212 ret = thermal_set_governor(tz, gov);
214 exit:
215 mutex_unlock(&tz->lock);
216 mutex_unlock(&thermal_governor_lock);
218 thermal_notify_tz_gov_change(tz->id, policy);
220 return ret;
223 int thermal_build_list_of_policies(char *buf)
225 struct thermal_governor *pos;
226 ssize_t count = 0;
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);
239 return count;
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)
252 int ret = 0;
253 struct thermal_governor **governor;
255 for_each_governor_table(governor) {
256 ret = thermal_register_governor(*governor);
257 if (ret) {
258 pr_err("Failed to register governor: '%s'",
259 (*governor)->name);
260 break;
263 pr_info("Registered thermal governor '%s'",
264 (*governor)->name);
267 if (ret) {
268 struct thermal_governor **gov;
270 for_each_governor_table(gov) {
271 if (gov == governor)
272 break;
273 thermal_unregister_governor(*gov);
277 return ret;
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().
286 * An update means:
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,
292 int delay)
294 if (delay > 1000)
295 mod_delayed_work(system_freezable_power_efficient_wq,
296 &tz->poll_queue,
297 round_jiffies(msecs_to_jiffies(delay)));
298 else if (delay)
299 mod_delayed_work(system_freezable_power_efficient_wq,
300 &tz->poll_queue,
301 msecs_to_jiffies(delay));
302 else
303 cancel_delayed_work(&tz->poll_queue);
306 static inline bool should_stop_polling(struct thermal_zone_device *tz)
308 return !thermal_zone_device_is_enabled(tz);
311 static void monitor_thermal_zone(struct thermal_zone_device *tz)
313 bool stop;
315 stop = should_stop_polling(tz);
317 mutex_lock(&tz->lock);
319 if (!stop && tz->passive)
320 thermal_zone_device_set_polling(tz, tz->passive_delay);
321 else if (!stop && tz->polling_delay)
322 thermal_zone_device_set_polling(tz, tz->polling_delay);
323 else
324 thermal_zone_device_set_polling(tz, 0);
326 mutex_unlock(&tz->lock);
329 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
331 tz->governor ? tz->governor->throttle(tz, trip) :
332 def_governor->throttle(tz, trip);
336 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
337 * @work: work_struct associated with the emergency poweroff function
339 * This function is called in very critical situations to force
340 * a kernel poweroff after a configurable timeout value.
342 static void thermal_emergency_poweroff_func(struct work_struct *work)
345 * We have reached here after the emergency thermal shutdown
346 * Waiting period has expired. This means orderly_poweroff has
347 * not been able to shut off the system for some reason.
348 * Try to shut down the system immediately using kernel_power_off
349 * if populated
351 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
352 kernel_power_off();
355 * Worst of the worst case trigger emergency restart
357 WARN(1, "Attempting emergency_restart: Temperature too high\n");
358 emergency_restart();
361 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
362 thermal_emergency_poweroff_func);
365 * thermal_emergency_poweroff - Trigger an emergency system poweroff
367 * This may be called from any critical situation to trigger a system shutdown
368 * after a known period of time. By default this is not scheduled.
370 static void thermal_emergency_poweroff(void)
372 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
374 * poweroff_delay_ms must be a carefully profiled positive value.
375 * Its a must for thermal_emergency_poweroff_work to be scheduled
377 if (poweroff_delay_ms <= 0)
378 return;
379 schedule_delayed_work(&thermal_emergency_poweroff_work,
380 msecs_to_jiffies(poweroff_delay_ms));
383 void thermal_zone_device_critical(struct thermal_zone_device *tz)
385 dev_emerg(&tz->device, "%s: critical temperature reached, "
386 "shutting down\n", tz->type);
388 mutex_lock(&poweroff_lock);
389 if (!power_off_triggered) {
391 * Queue a backup emergency shutdown in the event of
392 * orderly_poweroff failure
394 thermal_emergency_poweroff();
395 orderly_poweroff(true);
396 power_off_triggered = true;
398 mutex_unlock(&poweroff_lock);
400 EXPORT_SYMBOL(thermal_zone_device_critical);
402 static void handle_critical_trips(struct thermal_zone_device *tz,
403 int trip, enum thermal_trip_type trip_type)
405 int trip_temp;
407 tz->ops->get_trip_temp(tz, trip, &trip_temp);
409 /* If we have not crossed the trip_temp, we do not care. */
410 if (trip_temp <= 0 || tz->temperature < trip_temp)
411 return;
413 trace_thermal_zone_trip(tz, trip, trip_type);
415 if (tz->ops->notify)
416 tz->ops->notify(tz, trip, trip_type);
418 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
419 tz->ops->hot(tz);
420 else if (trip_type == THERMAL_TRIP_CRITICAL)
421 tz->ops->critical(tz);
424 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
426 enum thermal_trip_type type;
427 int trip_temp, hyst = 0;
429 /* Ignore disabled trip points */
430 if (test_bit(trip, &tz->trips_disabled))
431 return;
433 tz->ops->get_trip_temp(tz, trip, &trip_temp);
434 tz->ops->get_trip_type(tz, trip, &type);
435 if (tz->ops->get_trip_hyst)
436 tz->ops->get_trip_hyst(tz, trip, &hyst);
438 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
439 if (tz->last_temperature < trip_temp &&
440 tz->temperature >= trip_temp)
441 thermal_notify_tz_trip_up(tz->id, trip);
442 if (tz->last_temperature >= trip_temp &&
443 tz->temperature < (trip_temp - hyst))
444 thermal_notify_tz_trip_down(tz->id, trip);
447 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
448 handle_critical_trips(tz, trip, type);
449 else
450 handle_non_critical_trips(tz, trip);
452 * Alright, we handled this trip successfully.
453 * So, start monitoring again.
455 monitor_thermal_zone(tz);
458 static void update_temperature(struct thermal_zone_device *tz)
460 int temp, ret;
462 ret = thermal_zone_get_temp(tz, &temp);
463 if (ret) {
464 if (ret != -EAGAIN)
465 dev_warn(&tz->device,
466 "failed to read out thermal zone (%d)\n",
467 ret);
468 return;
471 mutex_lock(&tz->lock);
472 tz->last_temperature = tz->temperature;
473 tz->temperature = temp;
474 mutex_unlock(&tz->lock);
476 trace_thermal_temperature(tz);
478 thermal_genl_sampling_temp(tz->id, temp);
481 static void thermal_zone_device_init(struct thermal_zone_device *tz)
483 struct thermal_instance *pos;
484 tz->temperature = THERMAL_TEMP_INVALID;
485 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
486 pos->initialized = false;
489 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
491 tz->passive = 0;
492 thermal_zone_device_init(tz);
495 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
496 enum thermal_device_mode mode)
498 int ret = 0;
500 mutex_lock(&tz->lock);
502 /* do nothing if mode isn't changing */
503 if (mode == tz->mode) {
504 mutex_unlock(&tz->lock);
506 return ret;
509 if (tz->ops->change_mode)
510 ret = tz->ops->change_mode(tz, mode);
512 if (!ret)
513 tz->mode = mode;
515 mutex_unlock(&tz->lock);
517 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
519 if (mode == THERMAL_DEVICE_ENABLED)
520 thermal_notify_tz_enable(tz->id);
521 else
522 thermal_notify_tz_disable(tz->id);
524 return ret;
527 int thermal_zone_device_enable(struct thermal_zone_device *tz)
529 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
531 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
533 int thermal_zone_device_disable(struct thermal_zone_device *tz)
535 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
537 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
539 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
541 enum thermal_device_mode mode;
543 mutex_lock(&tz->lock);
545 mode = tz->mode;
547 mutex_unlock(&tz->lock);
549 return mode == THERMAL_DEVICE_ENABLED;
552 void thermal_zone_device_update(struct thermal_zone_device *tz,
553 enum thermal_notify_event event)
555 int count;
557 if (should_stop_polling(tz))
558 return;
560 if (atomic_read(&in_suspend))
561 return;
563 if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
564 "'get_temp' ops set\n", __func__))
565 return;
567 update_temperature(tz);
569 thermal_zone_set_trips(tz);
571 tz->notify_event = event;
573 for (count = 0; count < tz->trips; count++)
574 handle_thermal_trip(tz, count);
576 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
579 * thermal_notify_framework - Sensor drivers use this API to notify framework
580 * @tz: thermal zone device
581 * @trip: indicates which trip point has been crossed
583 * This function handles the trip events from sensor drivers. It starts
584 * throttling the cooling devices according to the policy configured.
585 * For CRITICAL and HOT trip points, this notifies the respective drivers,
586 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
587 * The throttling policy is based on the configured platform data; if no
588 * platform data is provided, this uses the step_wise throttling policy.
590 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
592 handle_thermal_trip(tz, trip);
594 EXPORT_SYMBOL_GPL(thermal_notify_framework);
596 static void thermal_zone_device_check(struct work_struct *work)
598 struct thermal_zone_device *tz = container_of(work, struct
599 thermal_zone_device,
600 poll_queue.work);
601 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
604 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
605 const char *cdev_type, size_t size)
607 struct thermal_cooling_device *cdev = NULL;
609 mutex_lock(&thermal_list_lock);
610 list_for_each_entry(cdev, &thermal_cdev_list, node) {
611 /* skip non matching cdevs */
612 if (strncmp(cdev_type, cdev->type, size))
613 continue;
615 /* re binding the exception matching the type pattern */
616 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
617 THERMAL_NO_LIMIT,
618 THERMAL_NO_LIMIT,
619 THERMAL_WEIGHT_DEFAULT);
621 mutex_unlock(&thermal_list_lock);
624 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
625 void *data)
627 struct thermal_governor *gov;
628 int ret = 0;
630 mutex_lock(&thermal_governor_lock);
631 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
632 ret = cb(gov, data);
633 if (ret)
634 break;
636 mutex_unlock(&thermal_governor_lock);
638 return ret;
641 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
642 void *), void *data)
644 struct thermal_cooling_device *cdev;
645 int ret = 0;
647 mutex_lock(&thermal_list_lock);
648 list_for_each_entry(cdev, &thermal_cdev_list, node) {
649 ret = cb(cdev, data);
650 if (ret)
651 break;
653 mutex_unlock(&thermal_list_lock);
655 return ret;
658 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
659 void *data)
661 struct thermal_zone_device *tz;
662 int ret = 0;
664 mutex_lock(&thermal_list_lock);
665 list_for_each_entry(tz, &thermal_tz_list, node) {
666 ret = cb(tz, data);
667 if (ret)
668 break;
670 mutex_unlock(&thermal_list_lock);
672 return ret;
675 struct thermal_zone_device *thermal_zone_get_by_id(int id)
677 struct thermal_zone_device *tz, *match = NULL;
679 mutex_lock(&thermal_list_lock);
680 list_for_each_entry(tz, &thermal_tz_list, node) {
681 if (tz->id == id) {
682 match = tz;
683 break;
686 mutex_unlock(&thermal_list_lock);
688 return match;
691 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
692 const char *cdev_type, size_t size)
694 struct thermal_cooling_device *cdev = NULL;
696 mutex_lock(&thermal_list_lock);
697 list_for_each_entry(cdev, &thermal_cdev_list, node) {
698 /* skip non matching cdevs */
699 if (strncmp(cdev_type, cdev->type, size))
700 continue;
701 /* unbinding the exception matching the type pattern */
702 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
703 cdev);
705 mutex_unlock(&thermal_list_lock);
709 * Device management section: cooling devices, zones devices, and binding
711 * Set of functions provided by the thermal core for:
712 * - cooling devices lifecycle: registration, unregistration,
713 * binding, and unbinding.
714 * - thermal zone devices lifecycle: registration, unregistration,
715 * binding, and unbinding.
719 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
720 * @tz: pointer to struct thermal_zone_device
721 * @trip: indicates which trip point the cooling devices is
722 * associated with in this thermal zone.
723 * @cdev: pointer to struct thermal_cooling_device
724 * @upper: the Maximum cooling state for this trip point.
725 * THERMAL_NO_LIMIT means no upper limit,
726 * and the cooling device can be in max_state.
727 * @lower: the Minimum cooling state can be used for this trip point.
728 * THERMAL_NO_LIMIT means no lower limit,
729 * and the cooling device can be in cooling state 0.
730 * @weight: The weight of the cooling device to be bound to the
731 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
732 * default value
734 * This interface function bind a thermal cooling device to the certain trip
735 * point of a thermal zone device.
736 * This function is usually called in the thermal zone device .bind callback.
738 * Return: 0 on success, the proper error value otherwise.
740 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
741 int trip,
742 struct thermal_cooling_device *cdev,
743 unsigned long upper, unsigned long lower,
744 unsigned int weight)
746 struct thermal_instance *dev;
747 struct thermal_instance *pos;
748 struct thermal_zone_device *pos1;
749 struct thermal_cooling_device *pos2;
750 unsigned long max_state;
751 int result, ret;
753 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
754 return -EINVAL;
756 list_for_each_entry(pos1, &thermal_tz_list, node) {
757 if (pos1 == tz)
758 break;
760 list_for_each_entry(pos2, &thermal_cdev_list, node) {
761 if (pos2 == cdev)
762 break;
765 if (tz != pos1 || cdev != pos2)
766 return -EINVAL;
768 ret = cdev->ops->get_max_state(cdev, &max_state);
769 if (ret)
770 return ret;
772 /* lower default 0, upper default max_state */
773 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
774 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
776 if (lower > upper || upper > max_state)
777 return -EINVAL;
779 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
780 if (!dev)
781 return -ENOMEM;
782 dev->tz = tz;
783 dev->cdev = cdev;
784 dev->trip = trip;
785 dev->upper = upper;
786 dev->lower = lower;
787 dev->target = THERMAL_NO_TARGET;
788 dev->weight = weight;
790 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
791 if (result < 0)
792 goto free_mem;
794 dev->id = result;
795 sprintf(dev->name, "cdev%d", dev->id);
796 result =
797 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
798 if (result)
799 goto release_ida;
801 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
802 sysfs_attr_init(&dev->attr.attr);
803 dev->attr.attr.name = dev->attr_name;
804 dev->attr.attr.mode = 0444;
805 dev->attr.show = trip_point_show;
806 result = device_create_file(&tz->device, &dev->attr);
807 if (result)
808 goto remove_symbol_link;
810 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
811 sysfs_attr_init(&dev->weight_attr.attr);
812 dev->weight_attr.attr.name = dev->weight_attr_name;
813 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
814 dev->weight_attr.show = weight_show;
815 dev->weight_attr.store = weight_store;
816 result = device_create_file(&tz->device, &dev->weight_attr);
817 if (result)
818 goto remove_trip_file;
820 mutex_lock(&tz->lock);
821 mutex_lock(&cdev->lock);
822 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
823 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
824 result = -EEXIST;
825 break;
827 if (!result) {
828 list_add_tail(&dev->tz_node, &tz->thermal_instances);
829 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
830 atomic_set(&tz->need_update, 1);
832 mutex_unlock(&cdev->lock);
833 mutex_unlock(&tz->lock);
835 if (!result)
836 return 0;
838 device_remove_file(&tz->device, &dev->weight_attr);
839 remove_trip_file:
840 device_remove_file(&tz->device, &dev->attr);
841 remove_symbol_link:
842 sysfs_remove_link(&tz->device.kobj, dev->name);
843 release_ida:
844 ida_simple_remove(&tz->ida, dev->id);
845 free_mem:
846 kfree(dev);
847 return result;
849 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
852 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
853 * thermal zone.
854 * @tz: pointer to a struct thermal_zone_device.
855 * @trip: indicates which trip point the cooling devices is
856 * associated with in this thermal zone.
857 * @cdev: pointer to a struct thermal_cooling_device.
859 * This interface function unbind a thermal cooling device from the certain
860 * trip point of a thermal zone device.
861 * This function is usually called in the thermal zone device .unbind callback.
863 * Return: 0 on success, the proper error value otherwise.
865 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
866 int trip,
867 struct thermal_cooling_device *cdev)
869 struct thermal_instance *pos, *next;
871 mutex_lock(&tz->lock);
872 mutex_lock(&cdev->lock);
873 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
874 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
875 list_del(&pos->tz_node);
876 list_del(&pos->cdev_node);
877 mutex_unlock(&cdev->lock);
878 mutex_unlock(&tz->lock);
879 goto unbind;
882 mutex_unlock(&cdev->lock);
883 mutex_unlock(&tz->lock);
885 return -ENODEV;
887 unbind:
888 device_remove_file(&tz->device, &pos->weight_attr);
889 device_remove_file(&tz->device, &pos->attr);
890 sysfs_remove_link(&tz->device.kobj, pos->name);
891 ida_simple_remove(&tz->ida, pos->id);
892 kfree(pos);
893 return 0;
895 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
897 static void thermal_release(struct device *dev)
899 struct thermal_zone_device *tz;
900 struct thermal_cooling_device *cdev;
902 if (!strncmp(dev_name(dev), "thermal_zone",
903 sizeof("thermal_zone") - 1)) {
904 tz = to_thermal_zone(dev);
905 thermal_zone_destroy_device_groups(tz);
906 kfree(tz);
907 } else if (!strncmp(dev_name(dev), "cooling_device",
908 sizeof("cooling_device") - 1)) {
909 cdev = to_cooling_device(dev);
910 kfree(cdev);
914 static struct class thermal_class = {
915 .name = "thermal",
916 .dev_release = thermal_release,
919 static inline
920 void print_bind_err_msg(struct thermal_zone_device *tz,
921 struct thermal_cooling_device *cdev, int ret)
923 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
924 tz->type, cdev->type, ret);
927 static void __bind(struct thermal_zone_device *tz, int mask,
928 struct thermal_cooling_device *cdev,
929 unsigned long *limits,
930 unsigned int weight)
932 int i, ret;
934 for (i = 0; i < tz->trips; i++) {
935 if (mask & (1 << i)) {
936 unsigned long upper, lower;
938 upper = THERMAL_NO_LIMIT;
939 lower = THERMAL_NO_LIMIT;
940 if (limits) {
941 lower = limits[i * 2];
942 upper = limits[i * 2 + 1];
944 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
945 upper, lower,
946 weight);
947 if (ret)
948 print_bind_err_msg(tz, cdev, ret);
953 static void bind_cdev(struct thermal_cooling_device *cdev)
955 int i, ret;
956 const struct thermal_zone_params *tzp;
957 struct thermal_zone_device *pos = NULL;
959 mutex_lock(&thermal_list_lock);
961 list_for_each_entry(pos, &thermal_tz_list, node) {
962 if (!pos->tzp && !pos->ops->bind)
963 continue;
965 if (pos->ops->bind) {
966 ret = pos->ops->bind(pos, cdev);
967 if (ret)
968 print_bind_err_msg(pos, cdev, ret);
969 continue;
972 tzp = pos->tzp;
973 if (!tzp || !tzp->tbp)
974 continue;
976 for (i = 0; i < tzp->num_tbps; i++) {
977 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
978 continue;
979 if (tzp->tbp[i].match(pos, cdev))
980 continue;
981 tzp->tbp[i].cdev = cdev;
982 __bind(pos, tzp->tbp[i].trip_mask, cdev,
983 tzp->tbp[i].binding_limits,
984 tzp->tbp[i].weight);
988 mutex_unlock(&thermal_list_lock);
992 * __thermal_cooling_device_register() - register a new thermal cooling device
993 * @np: a pointer to a device tree node.
994 * @type: the thermal cooling device type.
995 * @devdata: device private data.
996 * @ops: standard thermal cooling devices callbacks.
998 * This interface function adds a new thermal cooling device (fan/processor/...)
999 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1000 * to all the thermal zone devices registered at the same time.
1001 * It also gives the opportunity to link the cooling device to a device tree
1002 * node, so that it can be bound to a thermal zone created out of device tree.
1004 * Return: a pointer to the created struct thermal_cooling_device or an
1005 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1007 static struct thermal_cooling_device *
1008 __thermal_cooling_device_register(struct device_node *np,
1009 const char *type, void *devdata,
1010 const struct thermal_cooling_device_ops *ops)
1012 struct thermal_cooling_device *cdev;
1013 struct thermal_zone_device *pos = NULL;
1014 int result;
1016 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1017 return ERR_PTR(-EINVAL);
1019 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1020 !ops->set_cur_state)
1021 return ERR_PTR(-EINVAL);
1023 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1024 if (!cdev)
1025 return ERR_PTR(-ENOMEM);
1027 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1028 if (result < 0) {
1029 kfree(cdev);
1030 return ERR_PTR(result);
1033 cdev->id = result;
1034 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1035 mutex_init(&cdev->lock);
1036 INIT_LIST_HEAD(&cdev->thermal_instances);
1037 cdev->np = np;
1038 cdev->ops = ops;
1039 cdev->updated = false;
1040 cdev->device.class = &thermal_class;
1041 cdev->devdata = devdata;
1042 thermal_cooling_device_setup_sysfs(cdev);
1043 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1044 result = device_register(&cdev->device);
1045 if (result) {
1046 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1047 put_device(&cdev->device);
1048 return ERR_PTR(result);
1051 /* Add 'this' new cdev to the global cdev list */
1052 mutex_lock(&thermal_list_lock);
1053 list_add(&cdev->node, &thermal_cdev_list);
1054 mutex_unlock(&thermal_list_lock);
1056 /* Update binding information for 'this' new cdev */
1057 bind_cdev(cdev);
1059 mutex_lock(&thermal_list_lock);
1060 list_for_each_entry(pos, &thermal_tz_list, node)
1061 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1062 thermal_zone_device_update(pos,
1063 THERMAL_EVENT_UNSPECIFIED);
1064 mutex_unlock(&thermal_list_lock);
1066 return cdev;
1070 * thermal_cooling_device_register() - register a new thermal cooling device
1071 * @type: the thermal cooling device type.
1072 * @devdata: device private data.
1073 * @ops: standard thermal cooling devices callbacks.
1075 * This interface function adds a new thermal cooling device (fan/processor/...)
1076 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1077 * to all the thermal zone devices registered at the same time.
1079 * Return: a pointer to the created struct thermal_cooling_device or an
1080 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1082 struct thermal_cooling_device *
1083 thermal_cooling_device_register(const char *type, void *devdata,
1084 const struct thermal_cooling_device_ops *ops)
1086 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1088 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1091 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1092 * @np: a pointer to a device tree node.
1093 * @type: the thermal cooling device type.
1094 * @devdata: device private data.
1095 * @ops: standard thermal cooling devices callbacks.
1097 * This function will register a cooling device with device tree node reference.
1098 * This interface function adds a new thermal cooling device (fan/processor/...)
1099 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1100 * to all the thermal zone devices registered at the same time.
1102 * Return: a pointer to the created struct thermal_cooling_device or an
1103 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1105 struct thermal_cooling_device *
1106 thermal_of_cooling_device_register(struct device_node *np,
1107 const char *type, void *devdata,
1108 const struct thermal_cooling_device_ops *ops)
1110 return __thermal_cooling_device_register(np, type, devdata, ops);
1112 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1114 static void thermal_cooling_device_release(struct device *dev, void *res)
1116 thermal_cooling_device_unregister(
1117 *(struct thermal_cooling_device **)res);
1121 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1122 * device
1123 * @dev: a valid struct device pointer of a sensor device.
1124 * @np: a pointer to a device tree node.
1125 * @type: the thermal cooling device type.
1126 * @devdata: device private data.
1127 * @ops: standard thermal cooling devices callbacks.
1129 * This function will register a cooling device with device tree node reference.
1130 * This interface function adds a new thermal cooling device (fan/processor/...)
1131 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1132 * to all the thermal zone devices registered at the same time.
1134 * Return: a pointer to the created struct thermal_cooling_device or an
1135 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1137 struct thermal_cooling_device *
1138 devm_thermal_of_cooling_device_register(struct device *dev,
1139 struct device_node *np,
1140 char *type, void *devdata,
1141 const struct thermal_cooling_device_ops *ops)
1143 struct thermal_cooling_device **ptr, *tcd;
1145 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1146 GFP_KERNEL);
1147 if (!ptr)
1148 return ERR_PTR(-ENOMEM);
1150 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1151 if (IS_ERR(tcd)) {
1152 devres_free(ptr);
1153 return tcd;
1156 *ptr = tcd;
1157 devres_add(dev, ptr);
1159 return tcd;
1161 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1163 static void __unbind(struct thermal_zone_device *tz, int mask,
1164 struct thermal_cooling_device *cdev)
1166 int i;
1168 for (i = 0; i < tz->trips; i++)
1169 if (mask & (1 << i))
1170 thermal_zone_unbind_cooling_device(tz, i, cdev);
1174 * thermal_cooling_device_unregister - removes a thermal cooling device
1175 * @cdev: the thermal cooling device to remove.
1177 * thermal_cooling_device_unregister() must be called when a registered
1178 * thermal cooling device is no longer needed.
1180 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1182 int i;
1183 const struct thermal_zone_params *tzp;
1184 struct thermal_zone_device *tz;
1185 struct thermal_cooling_device *pos = NULL;
1187 if (!cdev)
1188 return;
1190 mutex_lock(&thermal_list_lock);
1191 list_for_each_entry(pos, &thermal_cdev_list, node)
1192 if (pos == cdev)
1193 break;
1194 if (pos != cdev) {
1195 /* thermal cooling device not found */
1196 mutex_unlock(&thermal_list_lock);
1197 return;
1199 list_del(&cdev->node);
1201 /* Unbind all thermal zones associated with 'this' cdev */
1202 list_for_each_entry(tz, &thermal_tz_list, node) {
1203 if (tz->ops->unbind) {
1204 tz->ops->unbind(tz, cdev);
1205 continue;
1208 if (!tz->tzp || !tz->tzp->tbp)
1209 continue;
1211 tzp = tz->tzp;
1212 for (i = 0; i < tzp->num_tbps; i++) {
1213 if (tzp->tbp[i].cdev == cdev) {
1214 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1215 tzp->tbp[i].cdev = NULL;
1220 mutex_unlock(&thermal_list_lock);
1222 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1223 device_del(&cdev->device);
1224 thermal_cooling_device_destroy_sysfs(cdev);
1225 put_device(&cdev->device);
1227 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1229 static void bind_tz(struct thermal_zone_device *tz)
1231 int i, ret;
1232 struct thermal_cooling_device *pos = NULL;
1233 const struct thermal_zone_params *tzp = tz->tzp;
1235 if (!tzp && !tz->ops->bind)
1236 return;
1238 mutex_lock(&thermal_list_lock);
1240 /* If there is ops->bind, try to use ops->bind */
1241 if (tz->ops->bind) {
1242 list_for_each_entry(pos, &thermal_cdev_list, node) {
1243 ret = tz->ops->bind(tz, pos);
1244 if (ret)
1245 print_bind_err_msg(tz, pos, ret);
1247 goto exit;
1250 if (!tzp || !tzp->tbp)
1251 goto exit;
1253 list_for_each_entry(pos, &thermal_cdev_list, node) {
1254 for (i = 0; i < tzp->num_tbps; i++) {
1255 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1256 continue;
1257 if (tzp->tbp[i].match(tz, pos))
1258 continue;
1259 tzp->tbp[i].cdev = pos;
1260 __bind(tz, tzp->tbp[i].trip_mask, pos,
1261 tzp->tbp[i].binding_limits,
1262 tzp->tbp[i].weight);
1265 exit:
1266 mutex_unlock(&thermal_list_lock);
1270 * thermal_zone_device_register() - register a new thermal zone device
1271 * @type: the thermal zone device type
1272 * @trips: the number of trip points the thermal zone support
1273 * @mask: a bit string indicating the writeablility of trip points
1274 * @devdata: private device data
1275 * @ops: standard thermal zone device callbacks
1276 * @tzp: thermal zone platform parameters
1277 * @passive_delay: number of milliseconds to wait between polls when
1278 * performing passive cooling
1279 * @polling_delay: number of milliseconds to wait between polls when checking
1280 * whether trip points have been crossed (0 for interrupt
1281 * driven systems)
1283 * This interface function adds a new thermal zone device (sensor) to
1284 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1285 * thermal cooling devices registered at the same time.
1286 * thermal_zone_device_unregister() must be called when the device is no
1287 * longer needed. The passive cooling depends on the .get_trend() return value.
1289 * Return: a pointer to the created struct thermal_zone_device or an
1290 * in case of error, an ERR_PTR. Caller must check return value with
1291 * IS_ERR*() helpers.
1293 struct thermal_zone_device *
1294 thermal_zone_device_register(const char *type, int trips, int mask,
1295 void *devdata, struct thermal_zone_device_ops *ops,
1296 struct thermal_zone_params *tzp, int passive_delay,
1297 int polling_delay)
1299 struct thermal_zone_device *tz;
1300 enum thermal_trip_type trip_type;
1301 int trip_temp;
1302 int id;
1303 int result;
1304 int count;
1305 struct thermal_governor *governor;
1307 if (!type || strlen(type) == 0) {
1308 pr_err("Error: No thermal zone type defined\n");
1309 return ERR_PTR(-EINVAL);
1312 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1313 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1314 type, THERMAL_NAME_LENGTH);
1315 return ERR_PTR(-EINVAL);
1318 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1319 pr_err("Error: Incorrect number of thermal trips\n");
1320 return ERR_PTR(-EINVAL);
1323 if (!ops) {
1324 pr_err("Error: Thermal zone device ops not defined\n");
1325 return ERR_PTR(-EINVAL);
1328 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1329 return ERR_PTR(-EINVAL);
1331 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1332 if (!tz)
1333 return ERR_PTR(-ENOMEM);
1335 INIT_LIST_HEAD(&tz->thermal_instances);
1336 ida_init(&tz->ida);
1337 mutex_init(&tz->lock);
1338 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1339 if (id < 0) {
1340 result = id;
1341 goto free_tz;
1344 tz->id = id;
1345 strlcpy(tz->type, type, sizeof(tz->type));
1347 if (!ops->critical)
1348 ops->critical = thermal_zone_device_critical;
1350 tz->ops = ops;
1351 tz->tzp = tzp;
1352 tz->device.class = &thermal_class;
1353 tz->devdata = devdata;
1354 tz->trips = trips;
1355 tz->passive_delay = passive_delay;
1356 tz->polling_delay = polling_delay;
1358 /* sys I/F */
1359 /* Add nodes that are always present via .groups */
1360 result = thermal_zone_create_device_groups(tz, mask);
1361 if (result)
1362 goto remove_id;
1364 /* A new thermal zone needs to be updated anyway. */
1365 atomic_set(&tz->need_update, 1);
1367 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1368 result = device_register(&tz->device);
1369 if (result)
1370 goto release_device;
1372 for (count = 0; count < trips; count++) {
1373 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1374 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1375 !trip_temp)
1376 set_bit(count, &tz->trips_disabled);
1379 /* Update 'this' zone's governor information */
1380 mutex_lock(&thermal_governor_lock);
1382 if (tz->tzp)
1383 governor = __find_governor(tz->tzp->governor_name);
1384 else
1385 governor = def_governor;
1387 result = thermal_set_governor(tz, governor);
1388 if (result) {
1389 mutex_unlock(&thermal_governor_lock);
1390 goto unregister;
1393 mutex_unlock(&thermal_governor_lock);
1395 if (!tz->tzp || !tz->tzp->no_hwmon) {
1396 result = thermal_add_hwmon_sysfs(tz);
1397 if (result)
1398 goto unregister;
1401 mutex_lock(&thermal_list_lock);
1402 list_add_tail(&tz->node, &thermal_tz_list);
1403 mutex_unlock(&thermal_list_lock);
1405 /* Bind cooling devices for this zone */
1406 bind_tz(tz);
1408 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1410 thermal_zone_device_reset(tz);
1411 /* Update the new thermal zone and mark it as already updated. */
1412 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1413 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1415 thermal_notify_tz_create(tz->id, tz->type);
1417 return tz;
1419 unregister:
1420 device_del(&tz->device);
1421 release_device:
1422 put_device(&tz->device);
1423 tz = NULL;
1424 remove_id:
1425 ida_simple_remove(&thermal_tz_ida, id);
1426 free_tz:
1427 kfree(tz);
1428 return ERR_PTR(result);
1430 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1433 * thermal_device_unregister - removes the registered thermal zone device
1434 * @tz: the thermal zone device to remove
1436 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1438 int i, tz_id;
1439 const struct thermal_zone_params *tzp;
1440 struct thermal_cooling_device *cdev;
1441 struct thermal_zone_device *pos = NULL;
1443 if (!tz)
1444 return;
1446 tzp = tz->tzp;
1447 tz_id = tz->id;
1449 mutex_lock(&thermal_list_lock);
1450 list_for_each_entry(pos, &thermal_tz_list, node)
1451 if (pos == tz)
1452 break;
1453 if (pos != tz) {
1454 /* thermal zone device not found */
1455 mutex_unlock(&thermal_list_lock);
1456 return;
1458 list_del(&tz->node);
1460 /* Unbind all cdevs associated with 'this' thermal zone */
1461 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1462 if (tz->ops->unbind) {
1463 tz->ops->unbind(tz, cdev);
1464 continue;
1467 if (!tzp || !tzp->tbp)
1468 break;
1470 for (i = 0; i < tzp->num_tbps; i++) {
1471 if (tzp->tbp[i].cdev == cdev) {
1472 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1473 tzp->tbp[i].cdev = NULL;
1478 mutex_unlock(&thermal_list_lock);
1480 cancel_delayed_work_sync(&tz->poll_queue);
1482 thermal_set_governor(tz, NULL);
1484 thermal_remove_hwmon_sysfs(tz);
1485 ida_simple_remove(&thermal_tz_ida, tz->id);
1486 ida_destroy(&tz->ida);
1487 mutex_destroy(&tz->lock);
1488 device_unregister(&tz->device);
1490 thermal_notify_tz_delete(tz_id);
1492 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1495 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1496 * @name: thermal zone name to fetch the temperature
1498 * When only one zone is found with the passed name, returns a reference to it.
1500 * Return: On success returns a reference to an unique thermal zone with
1501 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1502 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1504 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1506 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1507 unsigned int found = 0;
1509 if (!name)
1510 goto exit;
1512 mutex_lock(&thermal_list_lock);
1513 list_for_each_entry(pos, &thermal_tz_list, node)
1514 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1515 found++;
1516 ref = pos;
1518 mutex_unlock(&thermal_list_lock);
1520 /* nothing has been found, thus an error code for it */
1521 if (found == 0)
1522 ref = ERR_PTR(-ENODEV);
1523 else if (found > 1)
1524 /* Success only when an unique zone is found */
1525 ref = ERR_PTR(-EEXIST);
1527 exit:
1528 return ref;
1530 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1532 static int thermal_pm_notify(struct notifier_block *nb,
1533 unsigned long mode, void *_unused)
1535 struct thermal_zone_device *tz;
1537 switch (mode) {
1538 case PM_HIBERNATION_PREPARE:
1539 case PM_RESTORE_PREPARE:
1540 case PM_SUSPEND_PREPARE:
1541 atomic_set(&in_suspend, 1);
1542 break;
1543 case PM_POST_HIBERNATION:
1544 case PM_POST_RESTORE:
1545 case PM_POST_SUSPEND:
1546 atomic_set(&in_suspend, 0);
1547 list_for_each_entry(tz, &thermal_tz_list, node) {
1548 if (!thermal_zone_device_is_enabled(tz))
1549 continue;
1551 thermal_zone_device_init(tz);
1552 thermal_zone_device_update(tz,
1553 THERMAL_EVENT_UNSPECIFIED);
1555 break;
1556 default:
1557 break;
1559 return 0;
1562 static struct notifier_block thermal_pm_nb = {
1563 .notifier_call = thermal_pm_notify,
1566 static int __init thermal_init(void)
1568 int result;
1570 result = thermal_netlink_init();
1571 if (result)
1572 goto error;
1574 result = thermal_register_governors();
1575 if (result)
1576 goto error;
1578 result = class_register(&thermal_class);
1579 if (result)
1580 goto unregister_governors;
1582 result = of_parse_thermal_zones();
1583 if (result)
1584 goto unregister_class;
1586 result = register_pm_notifier(&thermal_pm_nb);
1587 if (result)
1588 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1589 result);
1591 return 0;
1593 unregister_class:
1594 class_unregister(&thermal_class);
1595 unregister_governors:
1596 thermal_unregister_governors();
1597 error:
1598 ida_destroy(&thermal_tz_ida);
1599 ida_destroy(&thermal_cdev_ida);
1600 mutex_destroy(&thermal_list_lock);
1601 mutex_destroy(&thermal_governor_lock);
1602 mutex_destroy(&poweroff_lock);
1603 return result;
1605 postcore_initcall(thermal_init);