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 "thermal_trace.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);
39
40static struct thermal_governor *def_governor;
41
42/*
43 * Governor section: set of functions to handle thermal governors
44 *
45 * Functions to help in the life cycle of thermal governors within
46 * the thermal core and by the thermal governor code.
47 */
48
49static struct thermal_governor *__find_governor(const char *name)
50{
51 struct thermal_governor *pos;
52
53 if (!name || !name[0])
54 return def_governor;
55
56 list_for_each_entry(pos, &thermal_governor_list, governor_list)
57 if (!strncasecmp(s1: name, s2: pos->name, THERMAL_NAME_LENGTH))
58 return pos;
59
60 return NULL;
61}
62
63/**
64 * bind_previous_governor() - bind the previous governor of the thermal zone
65 * @tz: a valid pointer to a struct thermal_zone_device
66 * @failed_gov_name: the name of the governor that failed to register
67 *
68 * Register the previous governor of the thermal zone after a new
69 * governor has failed to be bound.
70 */
71static void bind_previous_governor(struct thermal_zone_device *tz,
72 const char *failed_gov_name)
73{
74 if (tz->governor && tz->governor->bind_to_tz) {
75 if (tz->governor->bind_to_tz(tz)) {
76 dev_err(&tz->device,
77 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
78 failed_gov_name, tz->governor->name, tz->type);
79 tz->governor = NULL;
80 }
81 }
82}
83
84/**
85 * thermal_set_governor() - Switch to another governor
86 * @tz: a valid pointer to a struct thermal_zone_device
87 * @new_gov: pointer to the new governor
88 *
89 * Change the governor of thermal zone @tz.
90 *
91 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
92 */
93static int thermal_set_governor(struct thermal_zone_device *tz,
94 struct thermal_governor *new_gov)
95{
96 int ret = 0;
97
98 if (tz->governor && tz->governor->unbind_from_tz)
99 tz->governor->unbind_from_tz(tz);
100
101 if (new_gov && new_gov->bind_to_tz) {
102 ret = new_gov->bind_to_tz(tz);
103 if (ret) {
104 bind_previous_governor(tz, failed_gov_name: new_gov->name);
105
106 return ret;
107 }
108 }
109
110 tz->governor = new_gov;
111
112 return ret;
113}
114
115int thermal_register_governor(struct thermal_governor *governor)
116{
117 int err;
118 const char *name;
119 struct thermal_zone_device *pos;
120
121 if (!governor)
122 return -EINVAL;
123
124 mutex_lock(&thermal_governor_lock);
125
126 err = -EBUSY;
127 if (!__find_governor(name: governor->name)) {
128 bool match_default;
129
130 err = 0;
131 list_add(new: &governor->governor_list, head: &thermal_governor_list);
132 match_default = !strncmp(governor->name,
133 DEFAULT_THERMAL_GOVERNOR,
134 THERMAL_NAME_LENGTH);
135
136 if (!def_governor && match_default)
137 def_governor = governor;
138 }
139
140 mutex_lock(&thermal_list_lock);
141
142 list_for_each_entry(pos, &thermal_tz_list, node) {
143 /*
144 * only thermal zones with specified tz->tzp->governor_name
145 * may run with tz->govenor unset
146 */
147 if (pos->governor)
148 continue;
149
150 name = pos->tzp->governor_name;
151
152 if (!strncasecmp(s1: name, s2: governor->name, THERMAL_NAME_LENGTH)) {
153 int ret;
154
155 ret = thermal_set_governor(tz: pos, new_gov: governor);
156 if (ret)
157 dev_err(&pos->device,
158 "Failed to set governor %s for thermal zone %s: %d\n",
159 governor->name, pos->type, ret);
160 }
161 }
162
163 mutex_unlock(lock: &thermal_list_lock);
164 mutex_unlock(lock: &thermal_governor_lock);
165
166 return err;
167}
168
169void thermal_unregister_governor(struct thermal_governor *governor)
170{
171 struct thermal_zone_device *pos;
172
173 if (!governor)
174 return;
175
176 mutex_lock(&thermal_governor_lock);
177
178 if (!__find_governor(name: governor->name))
179 goto exit;
180
181 mutex_lock(&thermal_list_lock);
182
183 list_for_each_entry(pos, &thermal_tz_list, node) {
184 if (!strncasecmp(s1: pos->governor->name, s2: governor->name,
185 THERMAL_NAME_LENGTH))
186 thermal_set_governor(tz: pos, NULL);
187 }
188
189 mutex_unlock(lock: &thermal_list_lock);
190 list_del(entry: &governor->governor_list);
191exit:
192 mutex_unlock(lock: &thermal_governor_lock);
193}
194
195int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
196 char *policy)
197{
198 struct thermal_governor *gov;
199 int ret = -EINVAL;
200
201 mutex_lock(&thermal_governor_lock);
202 mutex_lock(&tz->lock);
203
204 gov = __find_governor(name: strim(policy));
205 if (!gov)
206 goto exit;
207
208 ret = thermal_set_governor(tz, new_gov: gov);
209
210exit:
211 mutex_unlock(lock: &tz->lock);
212 mutex_unlock(lock: &thermal_governor_lock);
213
214 thermal_notify_tz_gov_change(tz, name: policy);
215
216 return ret;
217}
218
219int thermal_build_list_of_policies(char *buf)
220{
221 struct thermal_governor *pos;
222 ssize_t count = 0;
223
224 mutex_lock(&thermal_governor_lock);
225
226 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
227 count += sysfs_emit_at(buf, at: count, fmt: "%s ", pos->name);
228 }
229 count += sysfs_emit_at(buf, at: count, fmt: "\n");
230
231 mutex_unlock(lock: &thermal_governor_lock);
232
233 return count;
234}
235
236static void __init thermal_unregister_governors(void)
237{
238 struct thermal_governor **governor;
239
240 for_each_governor_table(governor)
241 thermal_unregister_governor(governor: *governor);
242}
243
244static int __init thermal_register_governors(void)
245{
246 int ret = 0;
247 struct thermal_governor **governor;
248
249 for_each_governor_table(governor) {
250 ret = thermal_register_governor(governor: *governor);
251 if (ret) {
252 pr_err("Failed to register governor: '%s'",
253 (*governor)->name);
254 break;
255 }
256
257 pr_info("Registered thermal governor '%s'",
258 (*governor)->name);
259 }
260
261 if (ret) {
262 struct thermal_governor **gov;
263
264 for_each_governor_table(gov) {
265 if (gov == governor)
266 break;
267 thermal_unregister_governor(governor: *gov);
268 }
269 }
270
271 return ret;
272}
273
274/*
275 * Zone update section: main control loop applied to each zone while monitoring
276 * in polling mode. The monitoring is done using a workqueue.
277 * Same update may be done on a zone by calling thermal_zone_device_update().
278 *
279 * An update means:
280 * - Non-critical trips will invoke the governor responsible for that zone;
281 * - Hot trips will produce a notification to userspace;
282 * - Critical trip point will cause a system shutdown.
283 */
284static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
285 unsigned long delay)
286{
287 if (delay)
288 mod_delayed_work(wq: system_freezable_power_efficient_wq,
289 dwork: &tz->poll_queue, delay);
290 else
291 cancel_delayed_work(dwork: &tz->poll_queue);
292}
293
294static void monitor_thermal_zone(struct thermal_zone_device *tz)
295{
296 if (tz->mode != THERMAL_DEVICE_ENABLED)
297 thermal_zone_device_set_polling(tz, delay: 0);
298 else if (tz->passive)
299 thermal_zone_device_set_polling(tz, delay: tz->passive_delay_jiffies);
300 else if (tz->polling_delay_jiffies)
301 thermal_zone_device_set_polling(tz, delay: tz->polling_delay_jiffies);
302}
303
304static void handle_non_critical_trips(struct thermal_zone_device *tz,
305 const struct thermal_trip *trip)
306{
307 tz->governor ? tz->governor->throttle(tz, trip) :
308 def_governor->throttle(tz, trip);
309}
310
311void thermal_governor_update_tz(struct thermal_zone_device *tz,
312 enum thermal_notify_event reason)
313{
314 if (!tz->governor || !tz->governor->update_tz)
315 return;
316
317 tz->governor->update_tz(tz, reason);
318}
319
320static void thermal_zone_device_halt(struct thermal_zone_device *tz, bool shutdown)
321{
322 /*
323 * poweroff_delay_ms must be a carefully profiled positive value.
324 * Its a must for forced_emergency_poweroff_work to be scheduled.
325 */
326 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
327 const char *msg = "Temperature too high";
328
329 dev_emerg(&tz->device, "%s: critical temperature reached\n", tz->type);
330
331 if (shutdown)
332 hw_protection_shutdown(reason: msg, ms_until_forced: poweroff_delay_ms);
333 else
334 hw_protection_reboot(reason: msg, ms_until_forced: poweroff_delay_ms);
335}
336
337void thermal_zone_device_critical(struct thermal_zone_device *tz)
338{
339 thermal_zone_device_halt(tz, shutdown: true);
340}
341EXPORT_SYMBOL(thermal_zone_device_critical);
342
343void thermal_zone_device_critical_reboot(struct thermal_zone_device *tz)
344{
345 thermal_zone_device_halt(tz, shutdown: false);
346}
347
348static void handle_critical_trips(struct thermal_zone_device *tz,
349 const struct thermal_trip *trip)
350{
351 /* If we have not crossed the trip_temp, we do not care. */
352 if (trip->temperature <= 0 || tz->temperature < trip->temperature)
353 return;
354
355 trace_thermal_zone_trip(tz, trip: thermal_zone_trip_id(tz, trip), trip_type: trip->type);
356
357 if (trip->type == THERMAL_TRIP_CRITICAL)
358 tz->ops.critical(tz);
359 else if (tz->ops.hot)
360 tz->ops.hot(tz);
361}
362
363static void handle_thermal_trip(struct thermal_zone_device *tz,
364 struct thermal_trip *trip)
365{
366 if (trip->temperature == THERMAL_TEMP_INVALID)
367 return;
368
369 if (tz->last_temperature == THERMAL_TEMP_INVALID) {
370 /* Initialization. */
371 trip->threshold = trip->temperature;
372 if (tz->temperature >= trip->threshold)
373 trip->threshold -= trip->hysteresis;
374 } else if (tz->last_temperature < trip->threshold) {
375 /*
376 * The trip threshold is equal to the trip temperature, unless
377 * the latter has changed in the meantime. In either case,
378 * the trip is crossed if the current zone temperature is at
379 * least equal to its temperature, but otherwise ensure that
380 * the threshold and the trip temperature will be equal.
381 */
382 if (tz->temperature >= trip->temperature) {
383 thermal_notify_tz_trip_up(tz, trip);
384 thermal_debug_tz_trip_up(tz, trip);
385 trip->threshold = trip->temperature - trip->hysteresis;
386 } else {
387 trip->threshold = trip->temperature;
388 }
389 } else {
390 /*
391 * The previous zone temperature was above or equal to the trip
392 * threshold, which would be equal to the "low temperature" of
393 * the trip (its temperature minus its hysteresis), unless the
394 * trip temperature or hysteresis had changed. In either case,
395 * the trip is crossed if the current zone temperature is below
396 * the low temperature of the trip, but otherwise ensure that
397 * the trip threshold will be equal to the low temperature of
398 * the trip.
399 */
400 if (tz->temperature < trip->temperature - trip->hysteresis) {
401 thermal_notify_tz_trip_down(tz, trip);
402 thermal_debug_tz_trip_down(tz, trip);
403 trip->threshold = trip->temperature;
404 } else {
405 trip->threshold = trip->temperature - trip->hysteresis;
406 }
407 }
408
409 if (trip->type == THERMAL_TRIP_CRITICAL || trip->type == THERMAL_TRIP_HOT)
410 handle_critical_trips(tz, trip);
411 else
412 handle_non_critical_trips(tz, trip);
413}
414
415static void update_temperature(struct thermal_zone_device *tz)
416{
417 int temp, ret;
418
419 ret = __thermal_zone_get_temp(tz, temp: &temp);
420 if (ret) {
421 if (ret != -EAGAIN)
422 dev_warn(&tz->device,
423 "failed to read out thermal zone (%d)\n",
424 ret);
425 return;
426 }
427
428 tz->last_temperature = tz->temperature;
429 tz->temperature = temp;
430
431 trace_thermal_temperature(tz);
432
433 thermal_genl_sampling_temp(id: tz->id, temp);
434 thermal_debug_update_temp(tz);
435}
436
437static void thermal_zone_device_check(struct work_struct *work)
438{
439 struct thermal_zone_device *tz = container_of(work, struct
440 thermal_zone_device,
441 poll_queue.work);
442 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
443}
444
445static void thermal_zone_device_init(struct thermal_zone_device *tz)
446{
447 struct thermal_instance *pos;
448
449 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
450
451 tz->temperature = THERMAL_TEMP_INVALID;
452 tz->prev_low_trip = -INT_MAX;
453 tz->prev_high_trip = INT_MAX;
454 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
455 pos->initialized = false;
456}
457
458void __thermal_zone_device_update(struct thermal_zone_device *tz,
459 enum thermal_notify_event event)
460{
461 struct thermal_trip *trip;
462
463 if (tz->suspended)
464 return;
465
466 if (!thermal_zone_device_is_enabled(tz))
467 return;
468
469 update_temperature(tz);
470
471 __thermal_zone_set_trips(tz);
472
473 tz->notify_event = event;
474
475 for_each_trip(tz, trip)
476 handle_thermal_trip(tz, trip);
477
478 monitor_thermal_zone(tz);
479}
480
481static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
482 enum thermal_device_mode mode)
483{
484 int ret = 0;
485
486 mutex_lock(&tz->lock);
487
488 /* do nothing if mode isn't changing */
489 if (mode == tz->mode) {
490 mutex_unlock(lock: &tz->lock);
491
492 return ret;
493 }
494
495 if (tz->ops.change_mode)
496 ret = tz->ops.change_mode(tz, mode);
497
498 if (!ret)
499 tz->mode = mode;
500
501 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
502
503 mutex_unlock(lock: &tz->lock);
504
505 if (mode == THERMAL_DEVICE_ENABLED)
506 thermal_notify_tz_enable(tz);
507 else
508 thermal_notify_tz_disable(tz);
509
510 return ret;
511}
512
513int thermal_zone_device_enable(struct thermal_zone_device *tz)
514{
515 return thermal_zone_device_set_mode(tz, mode: THERMAL_DEVICE_ENABLED);
516}
517EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
518
519int thermal_zone_device_disable(struct thermal_zone_device *tz)
520{
521 return thermal_zone_device_set_mode(tz, mode: THERMAL_DEVICE_DISABLED);
522}
523EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
524
525int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
526{
527 lockdep_assert_held(&tz->lock);
528
529 return tz->mode == THERMAL_DEVICE_ENABLED;
530}
531
532static bool thermal_zone_is_present(struct thermal_zone_device *tz)
533{
534 return !list_empty(head: &tz->node);
535}
536
537void thermal_zone_device_update(struct thermal_zone_device *tz,
538 enum thermal_notify_event event)
539{
540 mutex_lock(&tz->lock);
541 if (thermal_zone_is_present(tz))
542 __thermal_zone_device_update(tz, event);
543 mutex_unlock(lock: &tz->lock);
544}
545EXPORT_SYMBOL_GPL(thermal_zone_device_update);
546
547int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
548 void *data)
549{
550 struct thermal_governor *gov;
551 int ret = 0;
552
553 mutex_lock(&thermal_governor_lock);
554 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
555 ret = cb(gov, data);
556 if (ret)
557 break;
558 }
559 mutex_unlock(lock: &thermal_governor_lock);
560
561 return ret;
562}
563
564int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
565 void *), void *data)
566{
567 struct thermal_cooling_device *cdev;
568 int ret = 0;
569
570 mutex_lock(&thermal_list_lock);
571 list_for_each_entry(cdev, &thermal_cdev_list, node) {
572 ret = cb(cdev, data);
573 if (ret)
574 break;
575 }
576 mutex_unlock(lock: &thermal_list_lock);
577
578 return ret;
579}
580
581int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
582 void *data)
583{
584 struct thermal_zone_device *tz;
585 int ret = 0;
586
587 mutex_lock(&thermal_list_lock);
588 list_for_each_entry(tz, &thermal_tz_list, node) {
589 ret = cb(tz, data);
590 if (ret)
591 break;
592 }
593 mutex_unlock(lock: &thermal_list_lock);
594
595 return ret;
596}
597
598struct thermal_zone_device *thermal_zone_get_by_id(int id)
599{
600 struct thermal_zone_device *tz, *match = NULL;
601
602 mutex_lock(&thermal_list_lock);
603 list_for_each_entry(tz, &thermal_tz_list, node) {
604 if (tz->id == id) {
605 match = tz;
606 break;
607 }
608 }
609 mutex_unlock(lock: &thermal_list_lock);
610
611 return match;
612}
613
614/*
615 * Device management section: cooling devices, zones devices, and binding
616 *
617 * Set of functions provided by the thermal core for:
618 * - cooling devices lifecycle: registration, unregistration,
619 * binding, and unbinding.
620 * - thermal zone devices lifecycle: registration, unregistration,
621 * binding, and unbinding.
622 */
623
624/**
625 * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
626 * @tz: pointer to struct thermal_zone_device
627 * @trip: trip point the cooling devices is associated with in this zone.
628 * @cdev: pointer to struct thermal_cooling_device
629 * @upper: the Maximum cooling state for this trip point.
630 * THERMAL_NO_LIMIT means no upper limit,
631 * and the cooling device can be in max_state.
632 * @lower: the Minimum cooling state can be used for this trip point.
633 * THERMAL_NO_LIMIT means no lower limit,
634 * and the cooling device can be in cooling state 0.
635 * @weight: The weight of the cooling device to be bound to the
636 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
637 * default value
638 *
639 * This interface function bind a thermal cooling device to the certain trip
640 * point of a thermal zone device.
641 * This function is usually called in the thermal zone device .bind callback.
642 *
643 * Return: 0 on success, the proper error value otherwise.
644 */
645int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
646 const struct thermal_trip *trip,
647 struct thermal_cooling_device *cdev,
648 unsigned long upper, unsigned long lower,
649 unsigned int weight)
650{
651 struct thermal_instance *dev;
652 struct thermal_instance *pos;
653 struct thermal_zone_device *pos1;
654 struct thermal_cooling_device *pos2;
655 bool upper_no_limit;
656 int result;
657
658 list_for_each_entry(pos1, &thermal_tz_list, node) {
659 if (pos1 == tz)
660 break;
661 }
662 list_for_each_entry(pos2, &thermal_cdev_list, node) {
663 if (pos2 == cdev)
664 break;
665 }
666
667 if (tz != pos1 || cdev != pos2)
668 return -EINVAL;
669
670 /* lower default 0, upper default max_state */
671 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
672
673 if (upper == THERMAL_NO_LIMIT) {
674 upper = cdev->max_state;
675 upper_no_limit = true;
676 } else {
677 upper_no_limit = false;
678 }
679
680 if (lower > upper || upper > cdev->max_state)
681 return -EINVAL;
682
683 dev = kzalloc(size: sizeof(*dev), GFP_KERNEL);
684 if (!dev)
685 return -ENOMEM;
686 dev->tz = tz;
687 dev->cdev = cdev;
688 dev->trip = trip;
689 dev->upper = upper;
690 dev->upper_no_limit = upper_no_limit;
691 dev->lower = lower;
692 dev->target = THERMAL_NO_TARGET;
693 dev->weight = weight;
694
695 result = ida_alloc(ida: &tz->ida, GFP_KERNEL);
696 if (result < 0)
697 goto free_mem;
698
699 dev->id = result;
700 sprintf(buf: dev->name, fmt: "cdev%d", dev->id);
701 result =
702 sysfs_create_link(kobj: &tz->device.kobj, target: &cdev->device.kobj, name: dev->name);
703 if (result)
704 goto release_ida;
705
706 snprintf(buf: dev->attr_name, size: sizeof(dev->attr_name), fmt: "cdev%d_trip_point",
707 dev->id);
708 sysfs_attr_init(&dev->attr.attr);
709 dev->attr.attr.name = dev->attr_name;
710 dev->attr.attr.mode = 0444;
711 dev->attr.show = trip_point_show;
712 result = device_create_file(device: &tz->device, entry: &dev->attr);
713 if (result)
714 goto remove_symbol_link;
715
716 snprintf(buf: dev->weight_attr_name, size: sizeof(dev->weight_attr_name),
717 fmt: "cdev%d_weight", dev->id);
718 sysfs_attr_init(&dev->weight_attr.attr);
719 dev->weight_attr.attr.name = dev->weight_attr_name;
720 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
721 dev->weight_attr.show = weight_show;
722 dev->weight_attr.store = weight_store;
723 result = device_create_file(device: &tz->device, entry: &dev->weight_attr);
724 if (result)
725 goto remove_trip_file;
726
727 mutex_lock(&tz->lock);
728 mutex_lock(&cdev->lock);
729 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
730 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
731 result = -EEXIST;
732 break;
733 }
734 if (!result) {
735 list_add_tail(new: &dev->tz_node, head: &tz->thermal_instances);
736 list_add_tail(new: &dev->cdev_node, head: &cdev->thermal_instances);
737 atomic_set(v: &tz->need_update, i: 1);
738
739 thermal_governor_update_tz(tz, reason: THERMAL_TZ_BIND_CDEV);
740 }
741 mutex_unlock(lock: &cdev->lock);
742 mutex_unlock(lock: &tz->lock);
743
744 if (!result)
745 return 0;
746
747 device_remove_file(dev: &tz->device, attr: &dev->weight_attr);
748remove_trip_file:
749 device_remove_file(dev: &tz->device, attr: &dev->attr);
750remove_symbol_link:
751 sysfs_remove_link(kobj: &tz->device.kobj, name: dev->name);
752release_ida:
753 ida_free(&tz->ida, id: dev->id);
754free_mem:
755 kfree(objp: dev);
756 return result;
757}
758EXPORT_SYMBOL_GPL(thermal_bind_cdev_to_trip);
759
760int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
761 int trip_index,
762 struct thermal_cooling_device *cdev,
763 unsigned long upper, unsigned long lower,
764 unsigned int weight)
765{
766 if (trip_index < 0 || trip_index >= tz->num_trips)
767 return -EINVAL;
768
769 return thermal_bind_cdev_to_trip(tz, &tz->trips[trip_index], cdev,
770 upper, lower, weight);
771}
772EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
773
774/**
775 * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
776 * @tz: pointer to a struct thermal_zone_device.
777 * @trip: trip point the cooling devices is associated with in this zone.
778 * @cdev: pointer to a struct thermal_cooling_device.
779 *
780 * This interface function unbind a thermal cooling device from the certain
781 * trip point of a thermal zone device.
782 * This function is usually called in the thermal zone device .unbind callback.
783 *
784 * Return: 0 on success, the proper error value otherwise.
785 */
786int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
787 const struct thermal_trip *trip,
788 struct thermal_cooling_device *cdev)
789{
790 struct thermal_instance *pos, *next;
791
792 mutex_lock(&tz->lock);
793 mutex_lock(&cdev->lock);
794 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
795 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
796 list_del(entry: &pos->tz_node);
797 list_del(entry: &pos->cdev_node);
798
799 thermal_governor_update_tz(tz, reason: THERMAL_TZ_UNBIND_CDEV);
800
801 mutex_unlock(lock: &cdev->lock);
802 mutex_unlock(lock: &tz->lock);
803 goto unbind;
804 }
805 }
806 mutex_unlock(lock: &cdev->lock);
807 mutex_unlock(lock: &tz->lock);
808
809 return -ENODEV;
810
811unbind:
812 device_remove_file(dev: &tz->device, attr: &pos->weight_attr);
813 device_remove_file(dev: &tz->device, attr: &pos->attr);
814 sysfs_remove_link(kobj: &tz->device.kobj, name: pos->name);
815 ida_free(&tz->ida, id: pos->id);
816 kfree(objp: pos);
817 return 0;
818}
819EXPORT_SYMBOL_GPL(thermal_unbind_cdev_from_trip);
820
821int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
822 int trip_index,
823 struct thermal_cooling_device *cdev)
824{
825 if (trip_index < 0 || trip_index >= tz->num_trips)
826 return -EINVAL;
827
828 return thermal_unbind_cdev_from_trip(tz, &tz->trips[trip_index], cdev);
829}
830EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
831
832static void thermal_release(struct device *dev)
833{
834 struct thermal_zone_device *tz;
835 struct thermal_cooling_device *cdev;
836
837 if (!strncmp(dev_name(dev), "thermal_zone",
838 sizeof("thermal_zone") - 1)) {
839 tz = to_thermal_zone(dev);
840 thermal_zone_destroy_device_groups(tz);
841 mutex_destroy(lock: &tz->lock);
842 complete(&tz->removal);
843 } else if (!strncmp(dev_name(dev), "cooling_device",
844 sizeof("cooling_device") - 1)) {
845 cdev = to_cooling_device(dev);
846 thermal_cooling_device_destroy_sysfs(cdev);
847 kfree_const(x: cdev->type);
848 ida_free(&thermal_cdev_ida, id: cdev->id);
849 kfree(objp: cdev);
850 }
851}
852
853static struct class *thermal_class;
854
855static inline
856void print_bind_err_msg(struct thermal_zone_device *tz,
857 struct thermal_cooling_device *cdev, int ret)
858{
859 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
860 tz->type, cdev->type, ret);
861}
862
863static void bind_cdev(struct thermal_cooling_device *cdev)
864{
865 int ret;
866 struct thermal_zone_device *pos = NULL;
867
868 list_for_each_entry(pos, &thermal_tz_list, node) {
869 if (pos->ops.bind) {
870 ret = pos->ops.bind(pos, cdev);
871 if (ret)
872 print_bind_err_msg(tz: pos, cdev, ret);
873 }
874 }
875}
876
877/**
878 * __thermal_cooling_device_register() - register a new thermal cooling device
879 * @np: a pointer to a device tree node.
880 * @type: the thermal cooling device type.
881 * @devdata: device private data.
882 * @ops: standard thermal cooling devices callbacks.
883 *
884 * This interface function adds a new thermal cooling device (fan/processor/...)
885 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
886 * to all the thermal zone devices registered at the same time.
887 * It also gives the opportunity to link the cooling device to a device tree
888 * node, so that it can be bound to a thermal zone created out of device tree.
889 *
890 * Return: a pointer to the created struct thermal_cooling_device or an
891 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
892 */
893static struct thermal_cooling_device *
894__thermal_cooling_device_register(struct device_node *np,
895 const char *type, void *devdata,
896 const struct thermal_cooling_device_ops *ops)
897{
898 struct thermal_cooling_device *cdev;
899 struct thermal_zone_device *pos = NULL;
900 int id, ret;
901
902 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
903 !ops->set_cur_state)
904 return ERR_PTR(error: -EINVAL);
905
906 if (!thermal_class)
907 return ERR_PTR(error: -ENODEV);
908
909 cdev = kzalloc(size: sizeof(*cdev), GFP_KERNEL);
910 if (!cdev)
911 return ERR_PTR(error: -ENOMEM);
912
913 ret = ida_alloc(ida: &thermal_cdev_ida, GFP_KERNEL);
914 if (ret < 0)
915 goto out_kfree_cdev;
916 cdev->id = ret;
917 id = ret;
918
919 cdev->type = kstrdup_const(s: type ? type : "", GFP_KERNEL);
920 if (!cdev->type) {
921 ret = -ENOMEM;
922 goto out_ida_remove;
923 }
924
925 mutex_init(&cdev->lock);
926 INIT_LIST_HEAD(list: &cdev->thermal_instances);
927 cdev->np = np;
928 cdev->ops = ops;
929 cdev->updated = false;
930 cdev->device.class = thermal_class;
931 cdev->devdata = devdata;
932
933 ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
934 if (ret)
935 goto out_cdev_type;
936
937 thermal_cooling_device_setup_sysfs(cdev);
938
939 ret = dev_set_name(dev: &cdev->device, name: "cooling_device%d", cdev->id);
940 if (ret)
941 goto out_cooling_dev;
942
943 ret = device_register(dev: &cdev->device);
944 if (ret) {
945 /* thermal_release() handles rest of the cleanup */
946 put_device(dev: &cdev->device);
947 return ERR_PTR(error: ret);
948 }
949
950 /* Add 'this' new cdev to the global cdev list */
951 mutex_lock(&thermal_list_lock);
952
953 list_add(new: &cdev->node, head: &thermal_cdev_list);
954
955 /* Update binding information for 'this' new cdev */
956 bind_cdev(cdev);
957
958 list_for_each_entry(pos, &thermal_tz_list, node)
959 if (atomic_cmpxchg(v: &pos->need_update, old: 1, new: 0))
960 thermal_zone_device_update(pos,
961 THERMAL_EVENT_UNSPECIFIED);
962
963 mutex_unlock(lock: &thermal_list_lock);
964
965 thermal_debug_cdev_add(cdev);
966
967 return cdev;
968
969out_cooling_dev:
970 thermal_cooling_device_destroy_sysfs(cdev);
971out_cdev_type:
972 kfree_const(x: cdev->type);
973out_ida_remove:
974 ida_free(&thermal_cdev_ida, id);
975out_kfree_cdev:
976 kfree(objp: cdev);
977 return ERR_PTR(error: ret);
978}
979
980/**
981 * thermal_cooling_device_register() - register a new thermal cooling device
982 * @type: the thermal cooling device type.
983 * @devdata: device private data.
984 * @ops: standard thermal cooling devices callbacks.
985 *
986 * This interface function adds a new thermal cooling device (fan/processor/...)
987 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
988 * to all the thermal zone devices registered at the same time.
989 *
990 * Return: a pointer to the created struct thermal_cooling_device or an
991 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
992 */
993struct thermal_cooling_device *
994thermal_cooling_device_register(const char *type, void *devdata,
995 const struct thermal_cooling_device_ops *ops)
996{
997 return __thermal_cooling_device_register(NULL, type, devdata, ops);
998}
999EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1000
1001/**
1002 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1003 * @np: a pointer to a device tree node.
1004 * @type: the thermal cooling device type.
1005 * @devdata: device private data.
1006 * @ops: standard thermal cooling devices callbacks.
1007 *
1008 * This function will register a cooling device with device tree node reference.
1009 * This interface function adds a new thermal cooling device (fan/processor/...)
1010 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1011 * to all the thermal zone devices registered at the same time.
1012 *
1013 * Return: a pointer to the created struct thermal_cooling_device or an
1014 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1015 */
1016struct thermal_cooling_device *
1017thermal_of_cooling_device_register(struct device_node *np,
1018 const char *type, void *devdata,
1019 const struct thermal_cooling_device_ops *ops)
1020{
1021 return __thermal_cooling_device_register(np, type, devdata, ops);
1022}
1023EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1024
1025static void thermal_cooling_device_release(struct device *dev, void *res)
1026{
1027 thermal_cooling_device_unregister(
1028 *(struct thermal_cooling_device **)res);
1029}
1030
1031/**
1032 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1033 * device
1034 * @dev: a valid struct device pointer of a sensor device.
1035 * @np: a pointer to a device tree node.
1036 * @type: the thermal cooling device type.
1037 * @devdata: device private data.
1038 * @ops: standard thermal cooling devices callbacks.
1039 *
1040 * This function will register a cooling device with device tree node reference.
1041 * This interface function adds a new thermal cooling device (fan/processor/...)
1042 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1043 * to all the thermal zone devices registered at the same time.
1044 *
1045 * Return: a pointer to the created struct thermal_cooling_device or an
1046 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1047 */
1048struct thermal_cooling_device *
1049devm_thermal_of_cooling_device_register(struct device *dev,
1050 struct device_node *np,
1051 char *type, void *devdata,
1052 const struct thermal_cooling_device_ops *ops)
1053{
1054 struct thermal_cooling_device **ptr, *tcd;
1055
1056 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1057 GFP_KERNEL);
1058 if (!ptr)
1059 return ERR_PTR(error: -ENOMEM);
1060
1061 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1062 if (IS_ERR(ptr: tcd)) {
1063 devres_free(res: ptr);
1064 return tcd;
1065 }
1066
1067 *ptr = tcd;
1068 devres_add(dev, res: ptr);
1069
1070 return tcd;
1071}
1072EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1073
1074static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1075{
1076 struct thermal_cooling_device *pos = NULL;
1077
1078 list_for_each_entry(pos, &thermal_cdev_list, node) {
1079 if (pos == cdev)
1080 return true;
1081 }
1082
1083 return false;
1084}
1085
1086/**
1087 * thermal_cooling_device_update - Update a cooling device object
1088 * @cdev: Target cooling device.
1089 *
1090 * Update @cdev to reflect a change of the underlying hardware or platform.
1091 *
1092 * Must be called when the maximum cooling state of @cdev becomes invalid and so
1093 * its .get_max_state() callback needs to be run to produce the new maximum
1094 * cooling state value.
1095 */
1096void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1097{
1098 struct thermal_instance *ti;
1099 unsigned long state;
1100
1101 if (IS_ERR_OR_NULL(ptr: cdev))
1102 return;
1103
1104 /*
1105 * Hold thermal_list_lock throughout the update to prevent the device
1106 * from going away while being updated.
1107 */
1108 mutex_lock(&thermal_list_lock);
1109
1110 if (!thermal_cooling_device_present(cdev))
1111 goto unlock_list;
1112
1113 /*
1114 * Update under the cdev lock to prevent the state from being set beyond
1115 * the new limit concurrently.
1116 */
1117 mutex_lock(&cdev->lock);
1118
1119 if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1120 goto unlock;
1121
1122 thermal_cooling_device_stats_reinit(cdev);
1123
1124 list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1125 if (ti->upper == cdev->max_state)
1126 continue;
1127
1128 if (ti->upper < cdev->max_state) {
1129 if (ti->upper_no_limit)
1130 ti->upper = cdev->max_state;
1131
1132 continue;
1133 }
1134
1135 ti->upper = cdev->max_state;
1136 if (ti->lower > ti->upper)
1137 ti->lower = ti->upper;
1138
1139 if (ti->target == THERMAL_NO_TARGET)
1140 continue;
1141
1142 if (ti->target > ti->upper)
1143 ti->target = ti->upper;
1144 }
1145
1146 if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1147 goto unlock;
1148
1149 thermal_cooling_device_stats_update(cdev, new_state: state);
1150
1151unlock:
1152 mutex_unlock(lock: &cdev->lock);
1153
1154unlock_list:
1155 mutex_unlock(lock: &thermal_list_lock);
1156}
1157EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1158
1159/**
1160 * thermal_cooling_device_unregister - removes a thermal cooling device
1161 * @cdev: the thermal cooling device to remove.
1162 *
1163 * thermal_cooling_device_unregister() must be called when a registered
1164 * thermal cooling device is no longer needed.
1165 */
1166void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1167{
1168 struct thermal_zone_device *tz;
1169
1170 if (!cdev)
1171 return;
1172
1173 thermal_debug_cdev_remove(cdev);
1174
1175 mutex_lock(&thermal_list_lock);
1176
1177 if (!thermal_cooling_device_present(cdev)) {
1178 mutex_unlock(lock: &thermal_list_lock);
1179 return;
1180 }
1181
1182 list_del(entry: &cdev->node);
1183
1184 /* Unbind all thermal zones associated with 'this' cdev */
1185 list_for_each_entry(tz, &thermal_tz_list, node) {
1186 if (tz->ops.unbind)
1187 tz->ops.unbind(tz, cdev);
1188 }
1189
1190 mutex_unlock(lock: &thermal_list_lock);
1191
1192 device_unregister(dev: &cdev->device);
1193}
1194EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1195
1196static void bind_tz(struct thermal_zone_device *tz)
1197{
1198 int ret;
1199 struct thermal_cooling_device *pos = NULL;
1200
1201 if (!tz->ops.bind)
1202 return;
1203
1204 mutex_lock(&thermal_list_lock);
1205
1206 list_for_each_entry(pos, &thermal_cdev_list, node) {
1207 ret = tz->ops.bind(tz, pos);
1208 if (ret)
1209 print_bind_err_msg(tz, cdev: pos, ret);
1210 }
1211
1212 mutex_unlock(lock: &thermal_list_lock);
1213}
1214
1215static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1216{
1217 *delay_jiffies = msecs_to_jiffies(m: delay_ms);
1218 if (delay_ms > 1000)
1219 *delay_jiffies = round_jiffies(j: *delay_jiffies);
1220}
1221
1222int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1223{
1224 int i, ret = -EINVAL;
1225
1226 if (tz->ops.get_crit_temp)
1227 return tz->ops.get_crit_temp(tz, temp);
1228
1229 mutex_lock(&tz->lock);
1230
1231 for (i = 0; i < tz->num_trips; i++) {
1232 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1233 *temp = tz->trips[i].temperature;
1234 ret = 0;
1235 break;
1236 }
1237 }
1238
1239 mutex_unlock(lock: &tz->lock);
1240
1241 return ret;
1242}
1243EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1244
1245/**
1246 * thermal_zone_device_register_with_trips() - register a new thermal zone device
1247 * @type: the thermal zone device type
1248 * @trips: a pointer to an array of thermal trips
1249 * @num_trips: the number of trip points the thermal zone support
1250 * @devdata: private device data
1251 * @ops: standard thermal zone device callbacks
1252 * @tzp: thermal zone platform parameters
1253 * @passive_delay: number of milliseconds to wait between polls when
1254 * performing passive cooling
1255 * @polling_delay: number of milliseconds to wait between polls when checking
1256 * whether trip points have been crossed (0 for interrupt
1257 * driven systems)
1258 *
1259 * This interface function adds a new thermal zone device (sensor) to
1260 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1261 * thermal cooling devices registered at the same time.
1262 * thermal_zone_device_unregister() must be called when the device is no
1263 * longer needed. The passive cooling depends on the .get_trend() return value.
1264 *
1265 * Return: a pointer to the created struct thermal_zone_device or an
1266 * in case of error, an ERR_PTR. Caller must check return value with
1267 * IS_ERR*() helpers.
1268 */
1269struct thermal_zone_device *
1270thermal_zone_device_register_with_trips(const char *type,
1271 const struct thermal_trip *trips,
1272 int num_trips, void *devdata,
1273 const struct thermal_zone_device_ops *ops,
1274 const struct thermal_zone_params *tzp,
1275 int passive_delay, int polling_delay)
1276{
1277 struct thermal_zone_device *tz;
1278 int id;
1279 int result;
1280 struct thermal_governor *governor;
1281
1282 if (!type || strlen(type) == 0) {
1283 pr_err("No thermal zone type defined\n");
1284 return ERR_PTR(error: -EINVAL);
1285 }
1286
1287 if (strlen(type) >= THERMAL_NAME_LENGTH) {
1288 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1289 type, THERMAL_NAME_LENGTH);
1290 return ERR_PTR(error: -EINVAL);
1291 }
1292
1293 if (num_trips < 0) {
1294 pr_err("Incorrect number of thermal trips\n");
1295 return ERR_PTR(error: -EINVAL);
1296 }
1297
1298 if (!ops || !ops->get_temp) {
1299 pr_err("Thermal zone device ops not defined\n");
1300 return ERR_PTR(error: -EINVAL);
1301 }
1302
1303 if (num_trips > 0 && !trips)
1304 return ERR_PTR(error: -EINVAL);
1305
1306 if (!thermal_class)
1307 return ERR_PTR(error: -ENODEV);
1308
1309 tz = kzalloc(struct_size(tz, trips, num_trips), GFP_KERNEL);
1310 if (!tz)
1311 return ERR_PTR(error: -ENOMEM);
1312
1313 if (tzp) {
1314 tz->tzp = kmemdup(p: tzp, size: sizeof(*tzp), GFP_KERNEL);
1315 if (!tz->tzp) {
1316 result = -ENOMEM;
1317 goto free_tz;
1318 }
1319 }
1320
1321 INIT_LIST_HEAD(list: &tz->thermal_instances);
1322 INIT_LIST_HEAD(list: &tz->node);
1323 ida_init(ida: &tz->ida);
1324 mutex_init(&tz->lock);
1325 init_completion(x: &tz->removal);
1326 id = ida_alloc(ida: &thermal_tz_ida, GFP_KERNEL);
1327 if (id < 0) {
1328 result = id;
1329 goto free_tzp;
1330 }
1331
1332 tz->id = id;
1333 strscpy(tz->type, type, sizeof(tz->type));
1334
1335 tz->ops = *ops;
1336 if (!tz->ops.critical)
1337 tz->ops.critical = thermal_zone_device_critical;
1338
1339 tz->device.class = thermal_class;
1340 tz->devdata = devdata;
1341 tz->num_trips = num_trips;
1342 memcpy(tz->trips, trips, num_trips * sizeof(*trips));
1343
1344 thermal_set_delay_jiffies(delay_jiffies: &tz->passive_delay_jiffies, delay_ms: passive_delay);
1345 thermal_set_delay_jiffies(delay_jiffies: &tz->polling_delay_jiffies, delay_ms: polling_delay);
1346
1347 /* sys I/F */
1348 /* Add nodes that are always present via .groups */
1349 result = thermal_zone_create_device_groups(tz);
1350 if (result)
1351 goto remove_id;
1352
1353 /* A new thermal zone needs to be updated anyway. */
1354 atomic_set(v: &tz->need_update, i: 1);
1355
1356 result = dev_set_name(dev: &tz->device, name: "thermal_zone%d", tz->id);
1357 if (result) {
1358 thermal_zone_destroy_device_groups(tz);
1359 goto remove_id;
1360 }
1361 result = device_register(dev: &tz->device);
1362 if (result)
1363 goto release_device;
1364
1365 /* Update 'this' zone's governor information */
1366 mutex_lock(&thermal_governor_lock);
1367
1368 if (tz->tzp)
1369 governor = __find_governor(name: tz->tzp->governor_name);
1370 else
1371 governor = def_governor;
1372
1373 result = thermal_set_governor(tz, new_gov: governor);
1374 if (result) {
1375 mutex_unlock(lock: &thermal_governor_lock);
1376 goto unregister;
1377 }
1378
1379 mutex_unlock(lock: &thermal_governor_lock);
1380
1381 if (!tz->tzp || !tz->tzp->no_hwmon) {
1382 result = thermal_add_hwmon_sysfs(tz);
1383 if (result)
1384 goto unregister;
1385 }
1386
1387 mutex_lock(&thermal_list_lock);
1388 mutex_lock(&tz->lock);
1389 list_add_tail(new: &tz->node, head: &thermal_tz_list);
1390 mutex_unlock(lock: &tz->lock);
1391 mutex_unlock(lock: &thermal_list_lock);
1392
1393 /* Bind cooling devices for this zone */
1394 bind_tz(tz);
1395
1396 thermal_zone_device_init(tz);
1397 /* Update the new thermal zone and mark it as already updated. */
1398 if (atomic_cmpxchg(v: &tz->need_update, old: 1, new: 0))
1399 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1400
1401 thermal_notify_tz_create(tz);
1402
1403 thermal_debug_tz_add(tz);
1404
1405 return tz;
1406
1407unregister:
1408 device_del(dev: &tz->device);
1409release_device:
1410 put_device(dev: &tz->device);
1411remove_id:
1412 ida_free(&thermal_tz_ida, id);
1413free_tzp:
1414 kfree(objp: tz->tzp);
1415free_tz:
1416 kfree(objp: tz);
1417 return ERR_PTR(error: result);
1418}
1419EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1420
1421struct thermal_zone_device *thermal_tripless_zone_device_register(
1422 const char *type,
1423 void *devdata,
1424 const struct thermal_zone_device_ops *ops,
1425 const struct thermal_zone_params *tzp)
1426{
1427 return thermal_zone_device_register_with_trips(type, NULL, 0, devdata,
1428 ops, tzp, 0, 0);
1429}
1430EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1431
1432void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1433{
1434 return tzd->devdata;
1435}
1436EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1437
1438const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1439{
1440 return tzd->type;
1441}
1442EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1443
1444int thermal_zone_device_id(struct thermal_zone_device *tzd)
1445{
1446 return tzd->id;
1447}
1448EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1449
1450struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1451{
1452 return &tzd->device;
1453}
1454EXPORT_SYMBOL_GPL(thermal_zone_device);
1455
1456/**
1457 * thermal_zone_device_unregister - removes the registered thermal zone device
1458 * @tz: the thermal zone device to remove
1459 */
1460void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1461{
1462 struct thermal_cooling_device *cdev;
1463 struct thermal_zone_device *pos = NULL;
1464
1465 if (!tz)
1466 return;
1467
1468 thermal_debug_tz_remove(tz);
1469
1470 mutex_lock(&thermal_list_lock);
1471 list_for_each_entry(pos, &thermal_tz_list, node)
1472 if (pos == tz)
1473 break;
1474 if (pos != tz) {
1475 /* thermal zone device not found */
1476 mutex_unlock(lock: &thermal_list_lock);
1477 return;
1478 }
1479
1480 mutex_lock(&tz->lock);
1481 list_del(entry: &tz->node);
1482 mutex_unlock(lock: &tz->lock);
1483
1484 /* Unbind all cdevs associated with 'this' thermal zone */
1485 list_for_each_entry(cdev, &thermal_cdev_list, node)
1486 if (tz->ops.unbind)
1487 tz->ops.unbind(tz, cdev);
1488
1489 mutex_unlock(lock: &thermal_list_lock);
1490
1491 cancel_delayed_work_sync(dwork: &tz->poll_queue);
1492
1493 thermal_set_governor(tz, NULL);
1494
1495 thermal_remove_hwmon_sysfs(tz);
1496 ida_free(&thermal_tz_ida, id: tz->id);
1497 ida_destroy(ida: &tz->ida);
1498
1499 device_del(dev: &tz->device);
1500
1501 kfree(objp: tz->tzp);
1502
1503 put_device(dev: &tz->device);
1504
1505 thermal_notify_tz_delete(tz);
1506
1507 wait_for_completion(&tz->removal);
1508 kfree(objp: tz);
1509}
1510EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1511
1512/**
1513 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1514 * @name: thermal zone name to fetch the temperature
1515 *
1516 * When only one zone is found with the passed name, returns a reference to it.
1517 *
1518 * Return: On success returns a reference to an unique thermal zone with
1519 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1520 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1521 */
1522struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1523{
1524 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(error: -EINVAL);
1525 unsigned int found = 0;
1526
1527 if (!name)
1528 goto exit;
1529
1530 mutex_lock(&thermal_list_lock);
1531 list_for_each_entry(pos, &thermal_tz_list, node)
1532 if (!strncasecmp(s1: name, s2: pos->type, THERMAL_NAME_LENGTH)) {
1533 found++;
1534 ref = pos;
1535 }
1536 mutex_unlock(lock: &thermal_list_lock);
1537
1538 /* nothing has been found, thus an error code for it */
1539 if (found == 0)
1540 ref = ERR_PTR(error: -ENODEV);
1541 else if (found > 1)
1542 /* Success only when an unique zone is found */
1543 ref = ERR_PTR(error: -EEXIST);
1544
1545exit:
1546 return ref;
1547}
1548EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1549
1550static void thermal_zone_device_resume(struct work_struct *work)
1551{
1552 struct thermal_zone_device *tz;
1553
1554 tz = container_of(work, struct thermal_zone_device, poll_queue.work);
1555
1556 mutex_lock(&tz->lock);
1557
1558 tz->suspended = false;
1559
1560 thermal_zone_device_init(tz);
1561 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
1562
1563 mutex_unlock(lock: &tz->lock);
1564}
1565
1566static int thermal_pm_notify(struct notifier_block *nb,
1567 unsigned long mode, void *_unused)
1568{
1569 struct thermal_zone_device *tz;
1570
1571 switch (mode) {
1572 case PM_HIBERNATION_PREPARE:
1573 case PM_RESTORE_PREPARE:
1574 case PM_SUSPEND_PREPARE:
1575 mutex_lock(&thermal_list_lock);
1576
1577 list_for_each_entry(tz, &thermal_tz_list, node) {
1578 mutex_lock(&tz->lock);
1579
1580 tz->suspended = true;
1581
1582 mutex_unlock(lock: &tz->lock);
1583 }
1584
1585 mutex_unlock(lock: &thermal_list_lock);
1586 break;
1587 case PM_POST_HIBERNATION:
1588 case PM_POST_RESTORE:
1589 case PM_POST_SUSPEND:
1590 mutex_lock(&thermal_list_lock);
1591
1592 list_for_each_entry(tz, &thermal_tz_list, node) {
1593 mutex_lock(&tz->lock);
1594
1595 cancel_delayed_work(dwork: &tz->poll_queue);
1596
1597 /*
1598 * Replace the work function with the resume one, which
1599 * will restore the original work function and schedule
1600 * the polling work if needed.
1601 */
1602 INIT_DELAYED_WORK(&tz->poll_queue,
1603 thermal_zone_device_resume);
1604 /* Queue up the work without a delay. */
1605 mod_delayed_work(wq: system_freezable_power_efficient_wq,
1606 dwork: &tz->poll_queue, delay: 0);
1607
1608 mutex_unlock(lock: &tz->lock);
1609 }
1610
1611 mutex_unlock(lock: &thermal_list_lock);
1612 break;
1613 default:
1614 break;
1615 }
1616 return 0;
1617}
1618
1619static struct notifier_block thermal_pm_nb = {
1620 .notifier_call = thermal_pm_notify,
1621};
1622
1623static int __init thermal_init(void)
1624{
1625 int result;
1626
1627 thermal_debug_init();
1628
1629 result = thermal_netlink_init();
1630 if (result)
1631 goto error;
1632
1633 result = thermal_register_governors();
1634 if (result)
1635 goto unregister_netlink;
1636
1637 thermal_class = kzalloc(size: sizeof(*thermal_class), GFP_KERNEL);
1638 if (!thermal_class) {
1639 result = -ENOMEM;
1640 goto unregister_governors;
1641 }
1642
1643 thermal_class->name = "thermal";
1644 thermal_class->dev_release = thermal_release;
1645
1646 result = class_register(class: thermal_class);
1647 if (result) {
1648 kfree(objp: thermal_class);
1649 thermal_class = NULL;
1650 goto unregister_governors;
1651 }
1652
1653 result = register_pm_notifier(nb: &thermal_pm_nb);
1654 if (result)
1655 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1656 result);
1657
1658 return 0;
1659
1660unregister_governors:
1661 thermal_unregister_governors();
1662unregister_netlink:
1663 thermal_netlink_exit();
1664error:
1665 mutex_destroy(lock: &thermal_list_lock);
1666 mutex_destroy(lock: &thermal_governor_lock);
1667 return result;
1668}
1669postcore_initcall(thermal_init);
1670

source code of linux/drivers/thermal/thermal_core.c