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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * thermal.c - Generic Thermal Management Sysfs support.
4 *
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 */
9
10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
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>
23
24#define CREATE_TRACE_POINTS
25#include <trace/events/thermal.h>
26
27#include "thermal_core.h"
28#include "thermal_hwmon.h"
29
30static DEFINE_IDA(thermal_tz_ida);
31static DEFINE_IDA(thermal_cdev_ida);
32
33static LIST_HEAD(thermal_tz_list);
34static LIST_HEAD(thermal_cdev_list);
35static LIST_HEAD(thermal_governor_list);
36
37static DEFINE_MUTEX(thermal_list_lock);
38static DEFINE_MUTEX(thermal_governor_lock);
39static DEFINE_MUTEX(poweroff_lock);
40
41static atomic_t in_suspend;
42static bool power_off_triggered;
43
44static struct thermal_governor *def_governor;
45
46/*
47 * Governor section: set of functions to handle thermal governors
48 *
49 * Functions to help in the life cycle of thermal governors within
50 * the thermal core and by the thermal governor code.
51 */
52
53static struct thermal_governor *__find_governor(const char *name)
54{
55 struct thermal_governor *pos;
56
57 if (!name || !name[0])
58 return def_governor;
59
60 list_for_each_entry(pos, &thermal_governor_list, governor_list)
61 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
62 return pos;
63
64 return NULL;
65}
66
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
71 *
72 * Register the previous governor of the thermal zone after a new
73 * governor has failed to be bound.
74 */
75static void bind_previous_governor(struct thermal_zone_device *tz,
76 const char *failed_gov_name)
77{
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;
84 }
85 }
86}
87
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
92 *
93 * Change the governor of thermal zone @tz.
94 *
95 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
96 */
97static int thermal_set_governor(struct thermal_zone_device *tz,
98 struct thermal_governor *new_gov)
99{
100 int ret = 0;
101
102 if (tz->governor && tz->governor->unbind_from_tz)
103 tz->governor->unbind_from_tz(tz);
104
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);
109
110 return ret;
111 }
112 }
113
114 tz->governor = new_gov;
115
116 return ret;
117}
118
119int thermal_register_governor(struct thermal_governor *governor)
120{
121 int err;
122 const char *name;
123 struct thermal_zone_device *pos;
124
125 if (!governor)
126 return -EINVAL;
127
128 mutex_lock(&thermal_governor_lock);
129
130 err = -EBUSY;
131 if (!__find_governor(governor->name)) {
132 bool match_default;
133
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);
139
140 if (!def_governor && match_default)
141 def_governor = governor;
142 }
143
144 mutex_lock(&thermal_list_lock);
145
146 list_for_each_entry(pos, &thermal_tz_list, node) {
147 /*
148 * only thermal zones with specified tz->tzp->governor_name
149 * may run with tz->govenor unset
150 */
151 if (pos->governor)
152 continue;
153
154 name = pos->tzp->governor_name;
155
156 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
157 int ret;
158
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);
164 }
165 }
166
167 mutex_unlock(&thermal_list_lock);
168 mutex_unlock(&thermal_governor_lock);
169
170 return err;
171}
172
173void thermal_unregister_governor(struct thermal_governor *governor)
174{
175 struct thermal_zone_device *pos;
176
177 if (!governor)
178 return;
179
180 mutex_lock(&thermal_governor_lock);
181
182 if (!__find_governor(governor->name))
183 goto exit;
184
185 mutex_lock(&thermal_list_lock);
186
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);
191 }
192
193 mutex_unlock(&thermal_list_lock);
194 list_del(&governor->governor_list);
195exit:
196 mutex_unlock(&thermal_governor_lock);
197}
198
199int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
200 char *policy)
201{
202 struct thermal_governor *gov;
203 int ret = -EINVAL;
204
205 mutex_lock(&thermal_governor_lock);
206 mutex_lock(&tz->lock);
207
208 gov = __find_governor(strim(policy));
209 if (!gov)
210 goto exit;
211
212 ret = thermal_set_governor(tz, gov);
213
214exit:
215 mutex_unlock(&tz->lock);
216 mutex_unlock(&thermal_governor_lock);
217
218 thermal_notify_tz_gov_change(tz->id, policy);
219
220 return ret;
221}
222
223int thermal_build_list_of_policies(char *buf)
224{
225 struct thermal_governor *pos;
226 ssize_t count = 0;
227 ssize_t size = PAGE_SIZE;
228
229 mutex_lock(&thermal_governor_lock);
230
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);
234 }
235 count += scnprintf(buf + count, size, "\n");
236
237 mutex_unlock(&thermal_governor_lock);
238
239 return count;
240}
241
242static void __init thermal_unregister_governors(void)
243{
244 struct thermal_governor **governor;
245
246 for_each_governor_table(governor)
247 thermal_unregister_governor(*governor);
248}
249
250static int __init thermal_register_governors(void)
251{
252 int ret = 0;
253 struct thermal_governor **governor;
254
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;
261 }
262
263 pr_info("Registered thermal governor '%s'",
264 (*governor)->name);
265 }
266
267 if (ret) {
268 struct thermal_governor **gov;
269
270 for_each_governor_table(gov) {
271 if (gov == governor)
272 break;
273 thermal_unregister_governor(*gov);
274 }
275 }
276
277 return ret;
278}
279
280/*
281 * Zone update section: main control loop applied to each zone while monitoring
282 *
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().
285 *
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.
290 */
291static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
292 int delay)
293{
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);
304}
305
306static inline bool should_stop_polling(struct thermal_zone_device *tz)
307{
308 return !thermal_zone_device_is_enabled(tz);
309}
310
311static void monitor_thermal_zone(struct thermal_zone_device *tz)
312{
313 bool stop;
314
315 stop = should_stop_polling(tz);
316
317 mutex_lock(&tz->lock);
318
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);
325
326 mutex_unlock(&tz->lock);
327}
328
329static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
330{
331 tz->governor ? tz->governor->throttle(tz, trip) :
332 def_governor->throttle(tz, trip);
333}
334
335/**
336 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
337 * @work: work_struct associated with the emergency poweroff function
338 *
339 * This function is called in very critical situations to force
340 * a kernel poweroff after a configurable timeout value.
341 */
342static void thermal_emergency_poweroff_func(struct work_struct *work)
343{
344 /*
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
350 */
351 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
352 kernel_power_off();
353
354 /*
355 * Worst of the worst case trigger emergency restart
356 */
357 WARN(1, "Attempting emergency_restart: Temperature too high\n");
358 emergency_restart();
359}
360
361static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
362 thermal_emergency_poweroff_func);
363
364/**
365 * thermal_emergency_poweroff - Trigger an emergency system poweroff
366 *
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.
369 */
370static void thermal_emergency_poweroff(void)
371{
372 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
373 /*
374 * poweroff_delay_ms must be a carefully profiled positive value.
375 * Its a must for thermal_emergency_poweroff_work to be scheduled
376 */
377 if (poweroff_delay_ms <= 0)
378 return;
379 schedule_delayed_work(&thermal_emergency_poweroff_work,
380 msecs_to_jiffies(poweroff_delay_ms));
381}
382
383static void handle_critical_trips(struct thermal_zone_device *tz,
384 int trip, enum thermal_trip_type trip_type)
385{
386 int trip_temp;
387
388 tz->ops->get_trip_temp(tz, trip, &trip_temp);
389
390 /* If we have not crossed the trip_temp, we do not care. */
391 if (trip_temp <= 0 || tz->temperature < trip_temp)
392 return;
393
394 trace_thermal_zone_trip(tz, trip, trip_type);
395
396 if (tz->ops->notify)
397 tz->ops->notify(tz, trip, trip_type);
398
399 if (trip_type == THERMAL_TRIP_CRITICAL) {
400 dev_emerg(&tz->device,
401 "critical temperature reached (%d C), shutting down\n",
402 tz->temperature / 1000);
403 mutex_lock(&poweroff_lock);
404 if (!power_off_triggered) {
405 /*
406 * Queue a backup emergency shutdown in the event of
407 * orderly_poweroff failure
408 */
409 thermal_emergency_poweroff();
410 orderly_poweroff(true);
411 power_off_triggered = true;
412 }
413 mutex_unlock(&poweroff_lock);
414 }
415}
416
417static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
418{
419 enum thermal_trip_type type;
420 int trip_temp, hyst = 0;
421
422 /* Ignore disabled trip points */
423 if (test_bit(trip, &tz->trips_disabled))
424 return;
425
426 tz->ops->get_trip_temp(tz, trip, &trip_temp);
427 tz->ops->get_trip_type(tz, trip, &type);
428 if (tz->ops->get_trip_hyst)
429 tz->ops->get_trip_hyst(tz, trip, &hyst);
430
431 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
432 if (tz->last_temperature < trip_temp &&
433 tz->temperature >= trip_temp)
434 thermal_notify_tz_trip_up(tz->id, trip);
435 if (tz->last_temperature >= trip_temp &&
436 tz->temperature < (trip_temp - hyst))
437 thermal_notify_tz_trip_down(tz->id, trip);
438 }
439
440 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
441 handle_critical_trips(tz, trip, type);
442 else
443 handle_non_critical_trips(tz, trip);
444 /*
445 * Alright, we handled this trip successfully.
446 * So, start monitoring again.
447 */
448 monitor_thermal_zone(tz);
449}
450
451static void update_temperature(struct thermal_zone_device *tz)
452{
453 int temp, ret;
454
455 ret = thermal_zone_get_temp(tz, &temp);
456 if (ret) {
457 if (ret != -EAGAIN)
458 dev_warn(&tz->device,
459 "failed to read out thermal zone (%d)\n",
460 ret);
461 return;
462 }
463
464 mutex_lock(&tz->lock);
465 tz->last_temperature = tz->temperature;
466 tz->temperature = temp;
467 mutex_unlock(&tz->lock);
468
469 trace_thermal_temperature(tz);
470
471 thermal_genl_sampling_temp(tz->id, temp);
472}
473
474static void thermal_zone_device_init(struct thermal_zone_device *tz)
475{
476 struct thermal_instance *pos;
477 tz->temperature = THERMAL_TEMP_INVALID;
478 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
479 pos->initialized = false;
480}
481
482static void thermal_zone_device_reset(struct thermal_zone_device *tz)
483{
484 tz->passive = 0;
485 thermal_zone_device_init(tz);
486}
487
488static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
489 enum thermal_device_mode mode)
490{
491 int ret = 0;
492
493 mutex_lock(&tz->lock);
494
495 /* do nothing if mode isn't changing */
496 if (mode == tz->mode) {
497 mutex_unlock(&tz->lock);
498
499 return ret;
500 }
501
502 if (tz->ops->change_mode)
503 ret = tz->ops->change_mode(tz, mode);
504
505 if (!ret)
506 tz->mode = mode;
507
508 mutex_unlock(&tz->lock);
509
510 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
511
512 if (mode == THERMAL_DEVICE_ENABLED)
513 thermal_notify_tz_enable(tz->id);
514 else
515 thermal_notify_tz_disable(tz->id);
516
517 return ret;
518}
519
520int thermal_zone_device_enable(struct thermal_zone_device *tz)
521{
522 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
523}
524EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
525
526int thermal_zone_device_disable(struct thermal_zone_device *tz)
527{
528 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
529}
530EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
531
532int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
533{
534 enum thermal_device_mode mode;
535
536 mutex_lock(&tz->lock);
537
538 mode = tz->mode;
539
540 mutex_unlock(&tz->lock);
541
542 return mode == THERMAL_DEVICE_ENABLED;
543}
544
545void thermal_zone_device_update(struct thermal_zone_device *tz,
546 enum thermal_notify_event event)
547{
548 int count;
549
550 if (should_stop_polling(tz))
551 return;
552
553 if (atomic_read(&in_suspend))
554 return;
555
556 if (!tz->ops->get_temp)
557 return;
558
559 update_temperature(tz);
560
561 thermal_zone_set_trips(tz);
562
563 tz->notify_event = event;
564
565 for (count = 0; count < tz->trips; count++)
566 handle_thermal_trip(tz, count);
567}
568EXPORT_SYMBOL_GPL(thermal_zone_device_update);
569
570/**
571 * thermal_notify_framework - Sensor drivers use this API to notify framework
572 * @tz: thermal zone device
573 * @trip: indicates which trip point has been crossed
574 *
575 * This function handles the trip events from sensor drivers. It starts
576 * throttling the cooling devices according to the policy configured.
577 * For CRITICAL and HOT trip points, this notifies the respective drivers,
578 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
579 * The throttling policy is based on the configured platform data; if no
580 * platform data is provided, this uses the step_wise throttling policy.
581 */
582void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
583{
584 handle_thermal_trip(tz, trip);
585}
586EXPORT_SYMBOL_GPL(thermal_notify_framework);
587
588static void thermal_zone_device_check(struct work_struct *work)
589{
590 struct thermal_zone_device *tz = container_of(work, struct
591 thermal_zone_device,
592 poll_queue.work);
593 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
594}
595
596/*
597 * Power actor section: interface to power actors to estimate power
598 *
599 * Set of functions used to interact to cooling devices that know
600 * how to estimate their devices power consumption.
601 */
602
603/**
604 * power_actor_get_max_power() - get the maximum power that a cdev can consume
605 * @cdev: pointer to &thermal_cooling_device
606 * @tz: a valid thermal zone device pointer
607 * @max_power: pointer in which to store the maximum power
608 *
609 * Calculate the maximum power consumption in milliwats that the
610 * cooling device can currently consume and store it in @max_power.
611 *
612 * Return: 0 on success, -EINVAL if @cdev doesn't support the
613 * power_actor API or -E* on other error.
614 */
615int power_actor_get_max_power(struct thermal_cooling_device *cdev,
616 struct thermal_zone_device *tz, u32 *max_power)
617{
618 if (!cdev_is_power_actor(cdev))
619 return -EINVAL;
620
621 return cdev->ops->state2power(cdev, tz, 0, max_power);
622}
623
624/**
625 * power_actor_get_min_power() - get the mainimum power that a cdev can consume
626 * @cdev: pointer to &thermal_cooling_device
627 * @tz: a valid thermal zone device pointer
628 * @min_power: pointer in which to store the minimum power
629 *
630 * Calculate the minimum power consumption in milliwatts that the
631 * cooling device can currently consume and store it in @min_power.
632 *
633 * Return: 0 on success, -EINVAL if @cdev doesn't support the
634 * power_actor API or -E* on other error.
635 */
636int power_actor_get_min_power(struct thermal_cooling_device *cdev,
637 struct thermal_zone_device *tz, u32 *min_power)
638{
639 unsigned long max_state;
640 int ret;
641
642 if (!cdev_is_power_actor(cdev))
643 return -EINVAL;
644
645 ret = cdev->ops->get_max_state(cdev, &max_state);
646 if (ret)
647 return ret;
648
649 return cdev->ops->state2power(cdev, tz, max_state, min_power);
650}
651
652/**
653 * power_actor_set_power() - limit the maximum power a cooling device consumes
654 * @cdev: pointer to &thermal_cooling_device
655 * @instance: thermal instance to update
656 * @power: the power in milliwatts
657 *
658 * Set the cooling device to consume at most @power milliwatts. The limit is
659 * expected to be a cap at the maximum power consumption.
660 *
661 * Return: 0 on success, -EINVAL if the cooling device does not
662 * implement the power actor API or -E* for other failures.
663 */
664int power_actor_set_power(struct thermal_cooling_device *cdev,
665 struct thermal_instance *instance, u32 power)
666{
667 unsigned long state;
668 int ret;
669
670 if (!cdev_is_power_actor(cdev))
671 return -EINVAL;
672
673 ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
674 if (ret)
675 return ret;
676
677 instance->target = state;
678 mutex_lock(&cdev->lock);
679 cdev->updated = false;
680 mutex_unlock(&cdev->lock);
681 thermal_cdev_update(cdev);
682
683 return 0;
684}
685
686void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
687 const char *cdev_type, size_t size)
688{
689 struct thermal_cooling_device *cdev = NULL;
690
691 mutex_lock(&thermal_list_lock);
692 list_for_each_entry(cdev, &thermal_cdev_list, node) {
693 /* skip non matching cdevs */
694 if (strncmp(cdev_type, cdev->type, size))
695 continue;
696
697 /* re binding the exception matching the type pattern */
698 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
699 THERMAL_NO_LIMIT,
700 THERMAL_NO_LIMIT,
701 THERMAL_WEIGHT_DEFAULT);
702 }
703 mutex_unlock(&thermal_list_lock);
704}
705
706int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
707 void *data)
708{
709 struct thermal_governor *gov;
710 int ret = 0;
711
712 mutex_lock(&thermal_governor_lock);
713 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
714 ret = cb(gov, data);
715 if (ret)
716 break;
717 }
718 mutex_unlock(&thermal_governor_lock);
719
720 return ret;
721}
722
723int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
724 void *), void *data)
725{
726 struct thermal_cooling_device *cdev;
727 int ret = 0;
728
729 mutex_lock(&thermal_list_lock);
730 list_for_each_entry(cdev, &thermal_cdev_list, node) {
731 ret = cb(cdev, data);
732 if (ret)
733 break;
734 }
735 mutex_unlock(&thermal_list_lock);
736
737 return ret;
738}
739
740int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
741 void *data)
742{
743 struct thermal_zone_device *tz;
744 int ret = 0;
745
746 mutex_lock(&thermal_list_lock);
747 list_for_each_entry(tz, &thermal_tz_list, node) {
748 ret = cb(tz, data);
749 if (ret)
750 break;
751 }
752 mutex_unlock(&thermal_list_lock);
753
754 return ret;
755}
756
757struct thermal_zone_device *thermal_zone_get_by_id(int id)
758{
759 struct thermal_zone_device *tz, *match = NULL;
760
761 mutex_lock(&thermal_list_lock);
762 list_for_each_entry(tz, &thermal_tz_list, node) {
763 if (tz->id == id) {
764 match = tz;
765 break;
766 }
767 }
768 mutex_unlock(&thermal_list_lock);
769
770 return match;
771}
772
773void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
774 const char *cdev_type, size_t size)
775{
776 struct thermal_cooling_device *cdev = NULL;
777
778 mutex_lock(&thermal_list_lock);
779 list_for_each_entry(cdev, &thermal_cdev_list, node) {
780 /* skip non matching cdevs */
781 if (strncmp(cdev_type, cdev->type, size))
782 continue;
783 /* unbinding the exception matching the type pattern */
784 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
785 cdev);
786 }
787 mutex_unlock(&thermal_list_lock);
788}
789
790/*
791 * Device management section: cooling devices, zones devices, and binding
792 *
793 * Set of functions provided by the thermal core for:
794 * - cooling devices lifecycle: registration, unregistration,
795 * binding, and unbinding.
796 * - thermal zone devices lifecycle: registration, unregistration,
797 * binding, and unbinding.
798 */
799
800/**
801 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
802 * @tz: pointer to struct thermal_zone_device
803 * @trip: indicates which trip point the cooling devices is
804 * associated with in this thermal zone.
805 * @cdev: pointer to struct thermal_cooling_device
806 * @upper: the Maximum cooling state for this trip point.
807 * THERMAL_NO_LIMIT means no upper limit,
808 * and the cooling device can be in max_state.
809 * @lower: the Minimum cooling state can be used for this trip point.
810 * THERMAL_NO_LIMIT means no lower limit,
811 * and the cooling device can be in cooling state 0.
812 * @weight: The weight of the cooling device to be bound to the
813 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
814 * default value
815 *
816 * This interface function bind a thermal cooling device to the certain trip
817 * point of a thermal zone device.
818 * This function is usually called in the thermal zone device .bind callback.
819 *
820 * Return: 0 on success, the proper error value otherwise.
821 */
822int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
823 int trip,
824 struct thermal_cooling_device *cdev,
825 unsigned long upper, unsigned long lower,
826 unsigned int weight)
827{
828 struct thermal_instance *dev;
829 struct thermal_instance *pos;
830 struct thermal_zone_device *pos1;
831 struct thermal_cooling_device *pos2;
832 unsigned long max_state;
833 int result, ret;
834
835 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
836 return -EINVAL;
837
838 list_for_each_entry(pos1, &thermal_tz_list, node) {
839 if (pos1 == tz)
840 break;
841 }
842 list_for_each_entry(pos2, &thermal_cdev_list, node) {
843 if (pos2 == cdev)
844 break;
845 }
846
847 if (tz != pos1 || cdev != pos2)
848 return -EINVAL;
849
850 ret = cdev->ops->get_max_state(cdev, &max_state);
851 if (ret)
852 return ret;
853
854 /* lower default 0, upper default max_state */
855 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
856 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
857
858 if (lower > upper || upper > max_state)
859 return -EINVAL;
860
861 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
862 if (!dev)
863 return -ENOMEM;
864 dev->tz = tz;
865 dev->cdev = cdev;
866 dev->trip = trip;
867 dev->upper = upper;
868 dev->lower = lower;
869 dev->target = THERMAL_NO_TARGET;
870 dev->weight = weight;
871
872 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
873 if (result < 0)
874 goto free_mem;
875
876 dev->id = result;
877 sprintf(dev->name, "cdev%d", dev->id);
878 result =
879 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
880 if (result)
881 goto release_ida;
882
883 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
884 sysfs_attr_init(&dev->attr.attr);
885 dev->attr.attr.name = dev->attr_name;
886 dev->attr.attr.mode = 0444;
887 dev->attr.show = trip_point_show;
888 result = device_create_file(&tz->device, &dev->attr);
889 if (result)
890 goto remove_symbol_link;
891
892 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
893 sysfs_attr_init(&dev->weight_attr.attr);
894 dev->weight_attr.attr.name = dev->weight_attr_name;
895 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
896 dev->weight_attr.show = weight_show;
897 dev->weight_attr.store = weight_store;
898 result = device_create_file(&tz->device, &dev->weight_attr);
899 if (result)
900 goto remove_trip_file;
901
902 mutex_lock(&tz->lock);
903 mutex_lock(&cdev->lock);
904 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
905 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
906 result = -EEXIST;
907 break;
908 }
909 if (!result) {
910 list_add_tail(&dev->tz_node, &tz->thermal_instances);
911 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
912 atomic_set(&tz->need_update, 1);
913 }
914 mutex_unlock(&cdev->lock);
915 mutex_unlock(&tz->lock);
916
917 if (!result)
918 return 0;
919
920 device_remove_file(&tz->device, &dev->weight_attr);
921remove_trip_file:
922 device_remove_file(&tz->device, &dev->attr);
923remove_symbol_link:
924 sysfs_remove_link(&tz->device.kobj, dev->name);
925release_ida:
926 ida_simple_remove(&tz->ida, dev->id);
927free_mem:
928 kfree(dev);
929 return result;
930}
931EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
932
933/**
934 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
935 * thermal zone.
936 * @tz: pointer to a struct thermal_zone_device.
937 * @trip: indicates which trip point the cooling devices is
938 * associated with in this thermal zone.
939 * @cdev: pointer to a struct thermal_cooling_device.
940 *
941 * This interface function unbind a thermal cooling device from the certain
942 * trip point of a thermal zone device.
943 * This function is usually called in the thermal zone device .unbind callback.
944 *
945 * Return: 0 on success, the proper error value otherwise.
946 */
947int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
948 int trip,
949 struct thermal_cooling_device *cdev)
950{
951 struct thermal_instance *pos, *next;
952
953 mutex_lock(&tz->lock);
954 mutex_lock(&cdev->lock);
955 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
956 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
957 list_del(&pos->tz_node);
958 list_del(&pos->cdev_node);
959 mutex_unlock(&cdev->lock);
960 mutex_unlock(&tz->lock);
961 goto unbind;
962 }
963 }
964 mutex_unlock(&cdev->lock);
965 mutex_unlock(&tz->lock);
966
967 return -ENODEV;
968
969unbind:
970 device_remove_file(&tz->device, &pos->weight_attr);
971 device_remove_file(&tz->device, &pos->attr);
972 sysfs_remove_link(&tz->device.kobj, pos->name);
973 ida_simple_remove(&tz->ida, pos->id);
974 kfree(pos);
975 return 0;
976}
977EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
978
979static void thermal_release(struct device *dev)
980{
981 struct thermal_zone_device *tz;
982 struct thermal_cooling_device *cdev;
983
984 if (!strncmp(dev_name(dev), "thermal_zone",
985 sizeof("thermal_zone") - 1)) {
986 tz = to_thermal_zone(dev);
987 thermal_zone_destroy_device_groups(tz);
988 kfree(tz);
989 } else if (!strncmp(dev_name(dev), "cooling_device",
990 sizeof("cooling_device") - 1)) {
991 cdev = to_cooling_device(dev);
992 kfree(cdev);
993 }
994}
995
996static struct class thermal_class = {
997 .name = "thermal",
998 .dev_release = thermal_release,
999};
1000
1001static inline
1002void print_bind_err_msg(struct thermal_zone_device *tz,
1003 struct thermal_cooling_device *cdev, int ret)
1004{
1005 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
1006 tz->type, cdev->type, ret);
1007}
1008
1009static void __bind(struct thermal_zone_device *tz, int mask,
1010 struct thermal_cooling_device *cdev,
1011 unsigned long *limits,
1012 unsigned int weight)
1013{
1014 int i, ret;
1015
1016 for (i = 0; i < tz->trips; i++) {
1017 if (mask & (1 << i)) {
1018 unsigned long upper, lower;
1019
1020 upper = THERMAL_NO_LIMIT;
1021 lower = THERMAL_NO_LIMIT;
1022 if (limits) {
1023 lower = limits[i * 2];
1024 upper = limits[i * 2 + 1];
1025 }
1026 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
1027 upper, lower,
1028 weight);
1029 if (ret)
1030 print_bind_err_msg(tz, cdev, ret);
1031 }
1032 }
1033}
1034
1035static void bind_cdev(struct thermal_cooling_device *cdev)
1036{
1037 int i, ret;
1038 const struct thermal_zone_params *tzp;
1039 struct thermal_zone_device *pos = NULL;
1040
1041 mutex_lock(&thermal_list_lock);
1042
1043 list_for_each_entry(pos, &thermal_tz_list, node) {
1044 if (!pos->tzp && !pos->ops->bind)
1045 continue;
1046
1047 if (pos->ops->bind) {
1048 ret = pos->ops->bind(pos, cdev);
1049 if (ret)
1050 print_bind_err_msg(pos, cdev, ret);
1051 continue;
1052 }
1053
1054 tzp = pos->tzp;
1055 if (!tzp || !tzp->tbp)
1056 continue;
1057
1058 for (i = 0; i < tzp->num_tbps; i++) {
1059 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1060 continue;
1061 if (tzp->tbp[i].match(pos, cdev))
1062 continue;
1063 tzp->tbp[i].cdev = cdev;
1064 __bind(pos, tzp->tbp[i].trip_mask, cdev,
1065 tzp->tbp[i].binding_limits,
1066 tzp->tbp[i].weight);
1067 }
1068 }
1069
1070 mutex_unlock(&thermal_list_lock);
1071}
1072
1073/**
1074 * __thermal_cooling_device_register() - register a new thermal cooling device
1075 * @np: a pointer to a device tree node.
1076 * @type: the thermal cooling device type.
1077 * @devdata: device private data.
1078 * @ops: standard thermal cooling devices callbacks.
1079 *
1080 * This interface function adds a new thermal cooling device (fan/processor/...)
1081 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1082 * to all the thermal zone devices registered at the same time.
1083 * It also gives the opportunity to link the cooling device to a device tree
1084 * node, so that it can be bound to a thermal zone created out of device tree.
1085 *
1086 * Return: a pointer to the created struct thermal_cooling_device or an
1087 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1088 */
1089static struct thermal_cooling_device *
1090__thermal_cooling_device_register(struct device_node *np,
1091 const char *type, void *devdata,
1092 const struct thermal_cooling_device_ops *ops)
1093{
1094 struct thermal_cooling_device *cdev;
1095 struct thermal_zone_device *pos = NULL;
1096 int result;
1097
1098 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1099 return ERR_PTR(-EINVAL);
1100
1101 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1102 !ops->set_cur_state)
1103 return ERR_PTR(-EINVAL);
1104
1105 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1106 if (!cdev)
1107 return ERR_PTR(-ENOMEM);
1108
1109 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1110 if (result < 0) {
1111 kfree(cdev);
1112 return ERR_PTR(result);
1113 }
1114
1115 cdev->id = result;
1116 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1117 mutex_init(&cdev->lock);
1118 INIT_LIST_HEAD(&cdev->thermal_instances);
1119 cdev->np = np;
1120 cdev->ops = ops;
1121 cdev->updated = false;
1122 cdev->device.class = &thermal_class;
1123 cdev->devdata = devdata;
1124 thermal_cooling_device_setup_sysfs(cdev);
1125 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1126 result = device_register(&cdev->device);
1127 if (result) {
1128 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1129 put_device(&cdev->device);
1130 return ERR_PTR(result);
1131 }
1132
1133 /* Add 'this' new cdev to the global cdev list */
1134 mutex_lock(&thermal_list_lock);
1135 list_add(&cdev->node, &thermal_cdev_list);
1136 mutex_unlock(&thermal_list_lock);
1137
1138 /* Update binding information for 'this' new cdev */
1139 bind_cdev(cdev);
1140
1141 mutex_lock(&thermal_list_lock);
1142 list_for_each_entry(pos, &thermal_tz_list, node)
1143 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1144 thermal_zone_device_update(pos,
1145 THERMAL_EVENT_UNSPECIFIED);
1146 mutex_unlock(&thermal_list_lock);
1147
1148 return cdev;
1149}
1150
1151/**
1152 * thermal_cooling_device_register() - register a new thermal cooling device
1153 * @type: the thermal cooling device type.
1154 * @devdata: device private data.
1155 * @ops: standard thermal cooling devices callbacks.
1156 *
1157 * This interface function adds a new thermal cooling device (fan/processor/...)
1158 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1159 * to all the thermal zone devices registered at the same time.
1160 *
1161 * Return: a pointer to the created struct thermal_cooling_device or an
1162 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1163 */
1164struct thermal_cooling_device *
1165thermal_cooling_device_register(const char *type, void *devdata,
1166 const struct thermal_cooling_device_ops *ops)
1167{
1168 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1169}
1170EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1171
1172/**
1173 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1174 * @np: a pointer to a device tree node.
1175 * @type: the thermal cooling device type.
1176 * @devdata: device private data.
1177 * @ops: standard thermal cooling devices callbacks.
1178 *
1179 * This function will register a cooling device with device tree node reference.
1180 * This interface function adds a new thermal cooling device (fan/processor/...)
1181 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1182 * to all the thermal zone devices registered at the same time.
1183 *
1184 * Return: a pointer to the created struct thermal_cooling_device or an
1185 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1186 */
1187struct thermal_cooling_device *
1188thermal_of_cooling_device_register(struct device_node *np,
1189 const char *type, void *devdata,
1190 const struct thermal_cooling_device_ops *ops)
1191{
1192 return __thermal_cooling_device_register(np, type, devdata, ops);
1193}
1194EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1195
1196static void thermal_cooling_device_release(struct device *dev, void *res)
1197{
1198 thermal_cooling_device_unregister(
1199 *(struct thermal_cooling_device **)res);
1200}
1201
1202/**
1203 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1204 * device
1205 * @dev: a valid struct device pointer of a sensor device.
1206 * @np: a pointer to a device tree node.
1207 * @type: the thermal cooling device type.
1208 * @devdata: device private data.
1209 * @ops: standard thermal cooling devices callbacks.
1210 *
1211 * This function will register a cooling device with device tree node reference.
1212 * This interface function adds a new thermal cooling device (fan/processor/...)
1213 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1214 * to all the thermal zone devices registered at the same time.
1215 *
1216 * Return: a pointer to the created struct thermal_cooling_device or an
1217 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1218 */
1219struct thermal_cooling_device *
1220devm_thermal_of_cooling_device_register(struct device *dev,
1221 struct device_node *np,
1222 char *type, void *devdata,
1223 const struct thermal_cooling_device_ops *ops)
1224{
1225 struct thermal_cooling_device **ptr, *tcd;
1226
1227 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1228 GFP_KERNEL);
1229 if (!ptr)
1230 return ERR_PTR(-ENOMEM);
1231
1232 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1233 if (IS_ERR(tcd)) {
1234 devres_free(ptr);
1235 return tcd;
1236 }
1237
1238 *ptr = tcd;
1239 devres_add(dev, ptr);
1240
1241 return tcd;
1242}
1243EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1244
1245static void __unbind(struct thermal_zone_device *tz, int mask,
1246 struct thermal_cooling_device *cdev)
1247{
1248 int i;
1249
1250 for (i = 0; i < tz->trips; i++)
1251 if (mask & (1 << i))
1252 thermal_zone_unbind_cooling_device(tz, i, cdev);
1253}
1254
1255/**
1256 * thermal_cooling_device_unregister - removes a thermal cooling device
1257 * @cdev: the thermal cooling device to remove.
1258 *
1259 * thermal_cooling_device_unregister() must be called when a registered
1260 * thermal cooling device is no longer needed.
1261 */
1262void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1263{
1264 int i;
1265 const struct thermal_zone_params *tzp;
1266 struct thermal_zone_device *tz;
1267 struct thermal_cooling_device *pos = NULL;
1268
1269 if (!cdev)
1270 return;
1271
1272 mutex_lock(&thermal_list_lock);
1273 list_for_each_entry(pos, &thermal_cdev_list, node)
1274 if (pos == cdev)
1275 break;
1276 if (pos != cdev) {
1277 /* thermal cooling device not found */
1278 mutex_unlock(&thermal_list_lock);
1279 return;
1280 }
1281 list_del(&cdev->node);
1282
1283 /* Unbind all thermal zones associated with 'this' cdev */
1284 list_for_each_entry(tz, &thermal_tz_list, node) {
1285 if (tz->ops->unbind) {
1286 tz->ops->unbind(tz, cdev);
1287 continue;
1288 }
1289
1290 if (!tz->tzp || !tz->tzp->tbp)
1291 continue;
1292
1293 tzp = tz->tzp;
1294 for (i = 0; i < tzp->num_tbps; i++) {
1295 if (tzp->tbp[i].cdev == cdev) {
1296 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1297 tzp->tbp[i].cdev = NULL;
1298 }
1299 }
1300 }
1301
1302 mutex_unlock(&thermal_list_lock);
1303
1304 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1305 device_del(&cdev->device);
1306 thermal_cooling_device_destroy_sysfs(cdev);
1307 put_device(&cdev->device);
1308}
1309EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1310
1311static void bind_tz(struct thermal_zone_device *tz)
1312{
1313 int i, ret;
1314 struct thermal_cooling_device *pos = NULL;
1315 const struct thermal_zone_params *tzp = tz->tzp;
1316
1317 if (!tzp && !tz->ops->bind)
1318 return;
1319
1320 mutex_lock(&thermal_list_lock);
1321
1322 /* If there is ops->bind, try to use ops->bind */
1323 if (tz->ops->bind) {
1324 list_for_each_entry(pos, &thermal_cdev_list, node) {
1325 ret = tz->ops->bind(tz, pos);
1326 if (ret)
1327 print_bind_err_msg(tz, pos, ret);
1328 }
1329 goto exit;
1330 }
1331
1332 if (!tzp || !tzp->tbp)
1333 goto exit;
1334
1335 list_for_each_entry(pos, &thermal_cdev_list, node) {
1336 for (i = 0; i < tzp->num_tbps; i++) {
1337 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1338 continue;
1339 if (tzp->tbp[i].match(tz, pos))
1340 continue;
1341 tzp->tbp[i].cdev = pos;
1342 __bind(tz, tzp->tbp[i].trip_mask, pos,
1343 tzp->tbp[i].binding_limits,
1344 tzp->tbp[i].weight);
1345 }
1346 }
1347exit:
1348 mutex_unlock(&thermal_list_lock);
1349}
1350
1351/**
1352 * thermal_zone_device_register() - register a new thermal zone device
1353 * @type: the thermal zone device type
1354 * @trips: the number of trip points the thermal zone support
1355 * @mask: a bit string indicating the writeablility of trip points
1356 * @devdata: private device data
1357 * @ops: standard thermal zone device callbacks
1358 * @tzp: thermal zone platform parameters
1359 * @passive_delay: number of milliseconds to wait between polls when
1360 * performing passive cooling
1361 * @polling_delay: number of milliseconds to wait between polls when checking
1362 * whether trip points have been crossed (0 for interrupt
1363 * driven systems)
1364 *
1365 * This interface function adds a new thermal zone device (sensor) to
1366 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1367 * thermal cooling devices registered at the same time.
1368 * thermal_zone_device_unregister() must be called when the device is no
1369 * longer needed. The passive cooling depends on the .get_trend() return value.
1370 *
1371 * Return: a pointer to the created struct thermal_zone_device or an
1372 * in case of error, an ERR_PTR. Caller must check return value with
1373 * IS_ERR*() helpers.
1374 */
1375struct thermal_zone_device *
1376thermal_zone_device_register(const char *type, int trips, int mask,
1377 void *devdata, struct thermal_zone_device_ops *ops,
1378 struct thermal_zone_params *tzp, int passive_delay,
1379 int polling_delay)
1380{
1381 struct thermal_zone_device *tz;
1382 enum thermal_trip_type trip_type;
1383 int trip_temp;
1384 int id;
1385 int result;
1386 int count;
1387 struct thermal_governor *governor;
1388
1389 if (!type || strlen(type) == 0) {
1390 pr_err("Error: No thermal zone type defined\n");
1391 return ERR_PTR(-EINVAL);
1392 }
1393
1394 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1395 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1396 type, THERMAL_NAME_LENGTH);
1397 return ERR_PTR(-EINVAL);
1398 }
1399
1400 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1401 pr_err("Error: Incorrect number of thermal trips\n");
1402 return ERR_PTR(-EINVAL);
1403 }
1404
1405 if (!ops) {
1406 pr_err("Error: Thermal zone device ops not defined\n");
1407 return ERR_PTR(-EINVAL);
1408 }
1409
1410 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1411 return ERR_PTR(-EINVAL);
1412
1413 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1414 if (!tz)
1415 return ERR_PTR(-ENOMEM);
1416
1417 INIT_LIST_HEAD(&tz->thermal_instances);
1418 ida_init(&tz->ida);
1419 mutex_init(&tz->lock);
1420 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1421 if (id < 0) {
1422 result = id;
1423 goto free_tz;
1424 }
1425
1426 tz->id = id;
1427 strlcpy(tz->type, type, sizeof(tz->type));
1428 tz->ops = ops;
1429 tz->tzp = tzp;
1430 tz->device.class = &thermal_class;
1431 tz->devdata = devdata;
1432 tz->trips = trips;
1433 tz->passive_delay = passive_delay;
1434 tz->polling_delay = polling_delay;
1435
1436 /* sys I/F */
1437 /* Add nodes that are always present via .groups */
1438 result = thermal_zone_create_device_groups(tz, mask);
1439 if (result)
1440 goto remove_id;
1441
1442 /* A new thermal zone needs to be updated anyway. */
1443 atomic_set(&tz->need_update, 1);
1444
1445 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1446 result = device_register(&tz->device);
1447 if (result)
1448 goto release_device;
1449
1450 for (count = 0; count < trips; count++) {
1451 if (tz->ops->get_trip_type(tz, count, &trip_type))
1452 set_bit(count, &tz->trips_disabled);
1453 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1454 set_bit(count, &tz->trips_disabled);
1455 /* Check for bogus trip points */
1456 if (trip_temp == 0)
1457 set_bit(count, &tz->trips_disabled);
1458 }
1459
1460 /* Update 'this' zone's governor information */
1461 mutex_lock(&thermal_governor_lock);
1462
1463 if (tz->tzp)
1464 governor = __find_governor(tz->tzp->governor_name);
1465 else
1466 governor = def_governor;
1467
1468 result = thermal_set_governor(tz, governor);
1469 if (result) {
1470 mutex_unlock(&thermal_governor_lock);
1471 goto unregister;
1472 }
1473
1474 mutex_unlock(&thermal_governor_lock);
1475
1476 if (!tz->tzp || !tz->tzp->no_hwmon) {
1477 result = thermal_add_hwmon_sysfs(tz);
1478 if (result)
1479 goto unregister;
1480 }
1481
1482 mutex_lock(&thermal_list_lock);
1483 list_add_tail(&tz->node, &thermal_tz_list);
1484 mutex_unlock(&thermal_list_lock);
1485
1486 /* Bind cooling devices for this zone */
1487 bind_tz(tz);
1488
1489 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1490
1491 thermal_zone_device_reset(tz);
1492 /* Update the new thermal zone and mark it as already updated. */
1493 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1494 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1495
1496 thermal_notify_tz_create(tz->id, tz->type);
1497
1498 return tz;
1499
1500unregister:
1501 device_del(&tz->device);
1502release_device:
1503 put_device(&tz->device);
1504 tz = NULL;
1505remove_id:
1506 ida_simple_remove(&thermal_tz_ida, id);
1507free_tz:
1508 kfree(tz);
1509 return ERR_PTR(result);
1510}
1511EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1512
1513/**
1514 * thermal_device_unregister - removes the registered thermal zone device
1515 * @tz: the thermal zone device to remove
1516 */
1517void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1518{
1519 int i, tz_id;
1520 const struct thermal_zone_params *tzp;
1521 struct thermal_cooling_device *cdev;
1522 struct thermal_zone_device *pos = NULL;
1523
1524 if (!tz)
1525 return;
1526
1527 tzp = tz->tzp;
1528 tz_id = tz->id;
1529
1530 mutex_lock(&thermal_list_lock);
1531 list_for_each_entry(pos, &thermal_tz_list, node)
1532 if (pos == tz)
1533 break;
1534 if (pos != tz) {
1535 /* thermal zone device not found */
1536 mutex_unlock(&thermal_list_lock);
1537 return;
1538 }
1539 list_del(&tz->node);
1540
1541 /* Unbind all cdevs associated with 'this' thermal zone */
1542 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1543 if (tz->ops->unbind) {
1544 tz->ops->unbind(tz, cdev);
1545 continue;
1546 }
1547
1548 if (!tzp || !tzp->tbp)
1549 break;
1550
1551 for (i = 0; i < tzp->num_tbps; i++) {
1552 if (tzp->tbp[i].cdev == cdev) {
1553 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1554 tzp->tbp[i].cdev = NULL;
1555 }
1556 }
1557 }
1558
1559 mutex_unlock(&thermal_list_lock);
1560
1561 cancel_delayed_work_sync(&tz->poll_queue);
1562
1563 thermal_set_governor(tz, NULL);
1564
1565 thermal_remove_hwmon_sysfs(tz);
1566 ida_simple_remove(&thermal_tz_ida, tz->id);
1567 ida_destroy(&tz->ida);
1568 mutex_destroy(&tz->lock);
1569 device_unregister(&tz->device);
1570
1571 thermal_notify_tz_delete(tz_id);
1572}
1573EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1574
1575/**
1576 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1577 * @name: thermal zone name to fetch the temperature
1578 *
1579 * When only one zone is found with the passed name, returns a reference to it.
1580 *
1581 * Return: On success returns a reference to an unique thermal zone with
1582 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1583 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1584 */
1585struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1586{
1587 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1588 unsigned int found = 0;
1589
1590 if (!name)
1591 goto exit;
1592
1593 mutex_lock(&thermal_list_lock);
1594 list_for_each_entry(pos, &thermal_tz_list, node)
1595 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1596 found++;
1597 ref = pos;
1598 }
1599 mutex_unlock(&thermal_list_lock);
1600
1601 /* nothing has been found, thus an error code for it */
1602 if (found == 0)
1603 ref = ERR_PTR(-ENODEV);
1604 else if (found > 1)
1605 /* Success only when an unique zone is found */
1606 ref = ERR_PTR(-EEXIST);
1607
1608exit:
1609 return ref;
1610}
1611EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1612
1613static int thermal_pm_notify(struct notifier_block *nb,
1614 unsigned long mode, void *_unused)
1615{
1616 struct thermal_zone_device *tz;
1617
1618 switch (mode) {
1619 case PM_HIBERNATION_PREPARE:
1620 case PM_RESTORE_PREPARE:
1621 case PM_SUSPEND_PREPARE:
1622 atomic_set(&in_suspend, 1);
1623 break;
1624 case PM_POST_HIBERNATION:
1625 case PM_POST_RESTORE:
1626 case PM_POST_SUSPEND:
1627 atomic_set(&in_suspend, 0);
1628 list_for_each_entry(tz, &thermal_tz_list, node) {
1629 if (!thermal_zone_device_is_enabled(tz))
1630 continue;
1631
1632 thermal_zone_device_init(tz);
1633 thermal_zone_device_update(tz,
1634 THERMAL_EVENT_UNSPECIFIED);
1635 }
1636 break;
1637 default:
1638 break;
1639 }
1640 return 0;
1641}
1642
1643static struct notifier_block thermal_pm_nb = {
1644 .notifier_call = thermal_pm_notify,
1645};
1646
1647static int __init thermal_init(void)
1648{
1649 int result;
1650
1651 result = thermal_netlink_init();
1652 if (result)
1653 goto error;
1654
1655 mutex_init(&poweroff_lock);
1656 result = thermal_register_governors();
1657 if (result)
1658 goto error;
1659
1660 result = class_register(&thermal_class);
1661 if (result)
1662 goto unregister_governors;
1663
1664 result = of_parse_thermal_zones();
1665 if (result)
1666 goto unregister_class;
1667
1668 result = register_pm_notifier(&thermal_pm_nb);
1669 if (result)
1670 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1671 result);
1672
1673 return 0;
1674
1675unregister_class:
1676 class_unregister(&thermal_class);
1677unregister_governors:
1678 thermal_unregister_governors();
1679error:
1680 ida_destroy(&thermal_tz_ida);
1681 ida_destroy(&thermal_cdev_ida);
1682 mutex_destroy(&thermal_list_lock);
1683 mutex_destroy(&thermal_governor_lock);
1684 mutex_destroy(&poweroff_lock);
1685 return result;
1686}
1687postcore_initcall(thermal_init);