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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 "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
42static bool thermal_pm_suspended;
43
44/*
45 * Governor section: set of functions to handle thermal governors
46 *
47 * Functions to help in the life cycle of thermal governors within
48 * the thermal core and by the thermal governor code.
49 */
50
51static struct thermal_governor *__find_governor(const char *name)
52{
53 struct thermal_governor *pos;
54
55 if (!name || !name[0])
56 return def_governor;
57
58 list_for_each_entry(pos, &thermal_governor_list, governor_list)
59 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
60 return pos;
61
62 return NULL;
63}
64
65/**
66 * bind_previous_governor() - bind the previous governor of the thermal zone
67 * @tz: a valid pointer to a struct thermal_zone_device
68 * @failed_gov_name: the name of the governor that failed to register
69 *
70 * Register the previous governor of the thermal zone after a new
71 * governor has failed to be bound.
72 */
73static void bind_previous_governor(struct thermal_zone_device *tz,
74 const char *failed_gov_name)
75{
76 if (tz->governor && tz->governor->bind_to_tz) {
77 if (tz->governor->bind_to_tz(tz)) {
78 dev_err(&tz->device,
79 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
80 failed_gov_name, tz->governor->name, tz->type);
81 tz->governor = NULL;
82 }
83 }
84}
85
86/**
87 * thermal_set_governor() - Switch to another governor
88 * @tz: a valid pointer to a struct thermal_zone_device
89 * @new_gov: pointer to the new governor
90 *
91 * Change the governor of thermal zone @tz.
92 *
93 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
94 */
95static int thermal_set_governor(struct thermal_zone_device *tz,
96 struct thermal_governor *new_gov)
97{
98 int ret = 0;
99
100 if (tz->governor && tz->governor->unbind_from_tz)
101 tz->governor->unbind_from_tz(tz);
102
103 if (new_gov && new_gov->bind_to_tz) {
104 ret = new_gov->bind_to_tz(tz);
105 if (ret) {
106 bind_previous_governor(tz, new_gov->name);
107
108 return ret;
109 }
110 }
111
112 tz->governor = new_gov;
113
114 return ret;
115}
116
117int thermal_register_governor(struct thermal_governor *governor)
118{
119 int err;
120 const char *name;
121 struct thermal_zone_device *pos;
122
123 if (!governor)
124 return -EINVAL;
125
126 guard(mutex)(&thermal_governor_lock);
127
128 err = -EBUSY;
129 if (!__find_governor(governor->name)) {
130 bool match_default;
131
132 err = 0;
133 list_add(&governor->governor_list, &thermal_governor_list);
134 match_default = !strncmp(governor->name,
135 DEFAULT_THERMAL_GOVERNOR,
136 THERMAL_NAME_LENGTH);
137
138 if (!def_governor && match_default)
139 def_governor = governor;
140 }
141
142 guard(mutex)(&thermal_list_lock);
143
144 list_for_each_entry(pos, &thermal_tz_list, node) {
145 /*
146 * only thermal zones with specified tz->tzp->governor_name
147 * may run with tz->govenor unset
148 */
149 if (pos->governor)
150 continue;
151
152 name = pos->tzp->governor_name;
153
154 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
155 int ret;
156
157 ret = thermal_set_governor(pos, governor);
158 if (ret)
159 dev_err(&pos->device,
160 "Failed to set governor %s for thermal zone %s: %d\n",
161 governor->name, pos->type, ret);
162 }
163 }
164
165 return err;
166}
167
168void thermal_unregister_governor(struct thermal_governor *governor)
169{
170 struct thermal_zone_device *pos;
171
172 if (!governor)
173 return;
174
175 guard(mutex)(&thermal_governor_lock);
176
177 if (!__find_governor(governor->name))
178 return;
179
180 list_del(&governor->governor_list);
181
182 guard(mutex)(&thermal_list_lock);
183
184 list_for_each_entry(pos, &thermal_tz_list, node) {
185 if (!strncasecmp(pos->governor->name, governor->name,
186 THERMAL_NAME_LENGTH))
187 thermal_set_governor(pos, NULL);
188 }
189}
190
191int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
192 char *policy)
193{
194 struct thermal_governor *gov;
195 int ret = -EINVAL;
196
197 guard(mutex)(&thermal_governor_lock);
198 guard(thermal_zone)(tz);
199
200 gov = __find_governor(strim(policy));
201 if (gov)
202 ret = thermal_set_governor(tz, gov);
203
204 thermal_notify_tz_gov_change(tz, policy);
205
206 return ret;
207}
208
209int thermal_build_list_of_policies(char *buf)
210{
211 struct thermal_governor *pos;
212 ssize_t count = 0;
213
214 guard(mutex)(&thermal_governor_lock);
215
216 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
217 count += sysfs_emit_at(buf, count, "%s ", pos->name);
218 }
219 count += sysfs_emit_at(buf, count, "\n");
220
221 return count;
222}
223
224static void __init thermal_unregister_governors(void)
225{
226 struct thermal_governor **governor;
227
228 for_each_governor_table(governor)
229 thermal_unregister_governor(*governor);
230}
231
232static int __init thermal_register_governors(void)
233{
234 int ret = 0;
235 struct thermal_governor **governor;
236
237 for_each_governor_table(governor) {
238 ret = thermal_register_governor(*governor);
239 if (ret) {
240 pr_err("Failed to register governor: '%s'",
241 (*governor)->name);
242 break;
243 }
244
245 pr_info("Registered thermal governor '%s'",
246 (*governor)->name);
247 }
248
249 if (ret) {
250 struct thermal_governor **gov;
251
252 for_each_governor_table(gov) {
253 if (gov == governor)
254 break;
255 thermal_unregister_governor(*gov);
256 }
257 }
258
259 return ret;
260}
261
262static int __thermal_zone_device_set_mode(struct thermal_zone_device *tz,
263 enum thermal_device_mode mode)
264{
265 if (tz->ops.change_mode) {
266 int ret;
267
268 ret = tz->ops.change_mode(tz, mode);
269 if (ret)
270 return ret;
271 }
272
273 tz->mode = mode;
274
275 return 0;
276}
277
278static void thermal_zone_broken_disable(struct thermal_zone_device *tz)
279{
280 struct thermal_trip_desc *td;
281
282 dev_err(&tz->device, "Unable to get temperature, disabling!\n");
283 /*
284 * This function only runs for enabled thermal zones, so no need to
285 * check for the current mode.
286 */
287 __thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
288 thermal_notify_tz_disable(tz);
289
290 for_each_trip_desc(tz, td) {
291 if (td->trip.type == THERMAL_TRIP_CRITICAL &&
292 td->trip.temperature > THERMAL_TEMP_INVALID) {
293 dev_crit(&tz->device,
294 "Disabled thermal zone with critical trip point\n");
295 return;
296 }
297 }
298}
299
300/*
301 * Zone update section: main control loop applied to each zone while monitoring
302 * in polling mode. The monitoring is done using a workqueue.
303 * Same update may be done on a zone by calling thermal_zone_device_update().
304 *
305 * An update means:
306 * - Non-critical trips will invoke the governor responsible for that zone;
307 * - Hot trips will produce a notification to userspace;
308 * - Critical trip point will cause a system shutdown.
309 */
310static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
311 unsigned long delay)
312{
313 if (delay > HZ)
314 delay = round_jiffies_relative(delay);
315
316 mod_delayed_work(system_freezable_power_efficient_wq, &tz->poll_queue, delay);
317}
318
319static void thermal_zone_recheck(struct thermal_zone_device *tz, int error)
320{
321 if (error == -EAGAIN) {
322 thermal_zone_device_set_polling(tz, THERMAL_RECHECK_DELAY);
323 return;
324 }
325
326 /*
327 * Print the message once to reduce log noise. It will be followed by
328 * another one if the temperature cannot be determined after multiple
329 * attempts.
330 */
331 if (tz->recheck_delay_jiffies == THERMAL_RECHECK_DELAY)
332 dev_info(&tz->device, "Temperature check failed (%d)\n", error);
333
334 thermal_zone_device_set_polling(tz, tz->recheck_delay_jiffies);
335
336 tz->recheck_delay_jiffies += max(tz->recheck_delay_jiffies >> 1, 1ULL);
337 if (tz->recheck_delay_jiffies > THERMAL_MAX_RECHECK_DELAY) {
338 thermal_zone_broken_disable(tz);
339 /*
340 * Restore the original recheck delay value to allow the thermal
341 * zone to try to recover when it is reenabled by user space.
342 */
343 tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
344 }
345}
346
347static void monitor_thermal_zone(struct thermal_zone_device *tz)
348{
349 if (tz->passive > 0 && tz->passive_delay_jiffies)
350 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
351 else if (tz->polling_delay_jiffies)
352 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
353}
354
355static struct thermal_governor *thermal_get_tz_governor(struct thermal_zone_device *tz)
356{
357 if (tz->governor)
358 return tz->governor;
359
360 return def_governor;
361}
362
363void thermal_governor_update_tz(struct thermal_zone_device *tz,
364 enum thermal_notify_event reason)
365{
366 if (!tz->governor || !tz->governor->update_tz)
367 return;
368
369 tz->governor->update_tz(tz, reason);
370}
371
372static void thermal_zone_device_halt(struct thermal_zone_device *tz, bool shutdown)
373{
374 /*
375 * poweroff_delay_ms must be a carefully profiled positive value.
376 * Its a must for forced_emergency_poweroff_work to be scheduled.
377 */
378 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
379 const char *msg = "Temperature too high";
380
381 dev_emerg(&tz->device, "%s: critical temperature reached\n", tz->type);
382
383 if (shutdown)
384 hw_protection_shutdown(msg, poweroff_delay_ms);
385 else
386 hw_protection_reboot(msg, poweroff_delay_ms);
387}
388
389void thermal_zone_device_critical(struct thermal_zone_device *tz)
390{
391 thermal_zone_device_halt(tz, true);
392}
393EXPORT_SYMBOL(thermal_zone_device_critical);
394
395void thermal_zone_device_critical_reboot(struct thermal_zone_device *tz)
396{
397 thermal_zone_device_halt(tz, false);
398}
399
400static void handle_critical_trips(struct thermal_zone_device *tz,
401 const struct thermal_trip *trip)
402{
403 trace_thermal_zone_trip(tz, thermal_zone_trip_id(tz, trip), trip->type);
404
405 if (trip->type == THERMAL_TRIP_CRITICAL)
406 tz->ops.critical(tz);
407 else if (tz->ops.hot)
408 tz->ops.hot(tz);
409}
410
411static void move_trip_to_sorted_list(struct thermal_trip_desc *td,
412 struct list_head *list)
413{
414 struct thermal_trip_desc *entry;
415
416 /*
417 * Delete upfront and then add to make relocation within the same list
418 * work.
419 */
420 list_del(&td->list_node);
421
422 /* Assume that the new entry is likely to be the last one. */
423 list_for_each_entry_reverse(entry, list, list_node) {
424 if (entry->threshold <= td->threshold) {
425 list_add(&td->list_node, &entry->list_node);
426 return;
427 }
428 }
429 list_add(&td->list_node, list);
430}
431
432static void move_to_trips_high(struct thermal_zone_device *tz,
433 struct thermal_trip_desc *td)
434{
435 td->threshold = td->trip.temperature;
436 move_trip_to_sorted_list(td, &tz->trips_high);
437}
438
439static void move_to_trips_reached(struct thermal_zone_device *tz,
440 struct thermal_trip_desc *td)
441{
442 td->threshold = td->trip.temperature - td->trip.hysteresis;
443 move_trip_to_sorted_list(td, &tz->trips_reached);
444}
445
446static void move_to_trips_invalid(struct thermal_zone_device *tz,
447 struct thermal_trip_desc *td)
448{
449 td->threshold = INT_MAX;
450 list_move(&td->list_node, &tz->trips_invalid);
451}
452
453static void thermal_governor_trip_crossed(struct thermal_governor *governor,
454 struct thermal_zone_device *tz,
455 const struct thermal_trip *trip,
456 bool crossed_up)
457{
458 if (trip->type == THERMAL_TRIP_HOT || trip->type == THERMAL_TRIP_CRITICAL)
459 return;
460
461 if (governor->trip_crossed)
462 governor->trip_crossed(tz, trip, crossed_up);
463}
464
465static void thermal_trip_crossed(struct thermal_zone_device *tz,
466 struct thermal_trip_desc *td,
467 struct thermal_governor *governor,
468 bool crossed_up)
469{
470 const struct thermal_trip *trip = &td->trip;
471
472 if (crossed_up) {
473 if (trip->type == THERMAL_TRIP_PASSIVE)
474 tz->passive++;
475 else if (trip->type == THERMAL_TRIP_CRITICAL ||
476 trip->type == THERMAL_TRIP_HOT)
477 handle_critical_trips(tz, trip);
478
479 thermal_notify_tz_trip_up(tz, trip);
480 thermal_debug_tz_trip_up(tz, trip);
481 } else {
482 if (trip->type == THERMAL_TRIP_PASSIVE) {
483 tz->passive--;
484 WARN_ON(tz->passive < 0);
485 }
486 thermal_notify_tz_trip_down(tz, trip);
487 thermal_debug_tz_trip_down(tz, trip);
488 }
489 thermal_governor_trip_crossed(governor, tz, trip, crossed_up);
490}
491
492void thermal_zone_set_trip_hyst(struct thermal_zone_device *tz,
493 struct thermal_trip *trip, int hyst)
494{
495 struct thermal_trip_desc *td = trip_to_trip_desc(trip);
496
497 WRITE_ONCE(trip->hysteresis, hyst);
498 thermal_notify_tz_trip_change(tz, trip);
499 /*
500 * If the zone temperature is above or at the trip tmperature, the trip
501 * is in the trips_reached list and its threshold is equal to its low
502 * temperature. It needs to stay in that list, but its threshold needs
503 * to be updated and the list ordering may need to be restored.
504 */
505 if (tz->temperature >= td->threshold)
506 move_to_trips_reached(tz, td);
507}
508
509void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
510 struct thermal_trip *trip, int temp)
511{
512 struct thermal_trip_desc *td = trip_to_trip_desc(trip);
513 int old_temp = trip->temperature;
514
515 if (old_temp == temp)
516 return;
517
518 WRITE_ONCE(trip->temperature, temp);
519 thermal_notify_tz_trip_change(tz, trip);
520
521 if (old_temp == THERMAL_TEMP_INVALID) {
522 /*
523 * The trip was invalid before the change, so move it to the
524 * trips_high list regardless of the new temperature value
525 * because there is no mitigation under way for it. If a
526 * mitigation needs to be started, the trip will be moved to the
527 * trips_reached list later.
528 */
529 move_to_trips_high(tz, td);
530 return;
531 }
532
533 if (temp == THERMAL_TEMP_INVALID) {
534 /*
535 * If the trip is in the trips_reached list, mitigation is under
536 * way for it and it needs to be stopped because the trip is
537 * effectively going away.
538 */
539 if (tz->temperature >= td->threshold)
540 thermal_trip_crossed(tz, td, thermal_get_tz_governor(tz), false);
541
542 move_to_trips_invalid(tz, td);
543 return;
544 }
545
546 /*
547 * The trip stays on its current list, but its threshold needs to be
548 * updated due to the temperature change and the list ordering may need
549 * to be restored.
550 */
551 if (tz->temperature >= td->threshold)
552 move_to_trips_reached(tz, td);
553 else
554 move_to_trips_high(tz, td);
555}
556EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
557
558static void thermal_zone_handle_trips(struct thermal_zone_device *tz,
559 struct thermal_governor *governor,
560 int *low, int *high)
561{
562 struct thermal_trip_desc *td, *next;
563 LIST_HEAD(way_down_list);
564
565 /* Check the trips that were below or at the zone temperature. */
566 list_for_each_entry_safe_reverse(td, next, &tz->trips_reached, list_node) {
567 if (td->threshold <= tz->temperature)
568 break;
569
570 thermal_trip_crossed(tz, td, governor, false);
571 /*
572 * The current trips_high list needs to be processed before
573 * adding new entries to it, so put them on a temporary list.
574 */
575 list_move(&td->list_node, &way_down_list);
576 }
577 /* Check the trips that were previously above the zone temperature. */
578 list_for_each_entry_safe(td, next, &tz->trips_high, list_node) {
579 if (td->threshold > tz->temperature)
580 break;
581
582 thermal_trip_crossed(tz, td, governor, true);
583 move_to_trips_reached(tz, td);
584 }
585 /* Move all of the trips from the temporary list to trips_high. */
586 list_for_each_entry_safe(td, next, &way_down_list, list_node)
587 move_to_trips_high(tz, td);
588
589 if (!list_empty(&tz->trips_reached)) {
590 td = list_last_entry(&tz->trips_reached,
591 struct thermal_trip_desc, list_node);
592 /*
593 * Set the "low" value below the current trip threshold in case
594 * the zone temperature is at that threshold and stays there,
595 * which would trigger a new interrupt immediately in vain.
596 */
597 *low = td->threshold - 1;
598 }
599 if (!list_empty(&tz->trips_high)) {
600 td = list_first_entry(&tz->trips_high,
601 struct thermal_trip_desc, list_node);
602 *high = td->threshold;
603 }
604}
605
606void __thermal_zone_device_update(struct thermal_zone_device *tz,
607 enum thermal_notify_event event)
608{
609 struct thermal_governor *governor = thermal_get_tz_governor(tz);
610 int low = -INT_MAX, high = INT_MAX;
611 int temp, ret;
612
613 if (tz->state != TZ_STATE_READY || tz->mode != THERMAL_DEVICE_ENABLED)
614 return;
615
616 ret = __thermal_zone_get_temp(tz, &temp);
617 if (ret) {
618 thermal_zone_recheck(tz, ret);
619 return;
620 } else if (temp <= THERMAL_TEMP_INVALID) {
621 /*
622 * Special case: No valid temperature value is available, but
623 * the zone owner does not want the core to do anything about
624 * it. Continue regular zone polling if needed, so that this
625 * function can be called again, but skip everything else.
626 */
627 goto monitor;
628 }
629
630 tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
631
632 tz->last_temperature = tz->temperature;
633 tz->temperature = temp;
634
635 trace_thermal_temperature(tz);
636
637 thermal_genl_sampling_temp(tz->id, temp);
638
639 tz->notify_event = event;
640
641 thermal_zone_handle_trips(tz, governor, &low, &high);
642
643 thermal_thresholds_handle(tz, &low, &high);
644
645 thermal_zone_set_trips(tz, low, high);
646
647 if (governor->manage)
648 governor->manage(tz);
649
650 thermal_debug_update_trip_stats(tz);
651
652monitor:
653 monitor_thermal_zone(tz);
654}
655
656static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
657 enum thermal_device_mode mode)
658{
659 int ret;
660
661 guard(thermal_zone)(tz);
662
663 /* do nothing if mode isn't changing */
664 if (mode == tz->mode)
665 return 0;
666
667 ret = __thermal_zone_device_set_mode(tz, mode);
668 if (ret)
669 return ret;
670
671 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
672
673 if (mode == THERMAL_DEVICE_ENABLED)
674 thermal_notify_tz_enable(tz);
675 else
676 thermal_notify_tz_disable(tz);
677
678 return 0;
679}
680
681int thermal_zone_device_enable(struct thermal_zone_device *tz)
682{
683 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
684}
685EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
686
687int thermal_zone_device_disable(struct thermal_zone_device *tz)
688{
689 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
690}
691EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
692
693static bool thermal_zone_is_present(struct thermal_zone_device *tz)
694{
695 return !list_empty(&tz->node);
696}
697
698void thermal_zone_device_update(struct thermal_zone_device *tz,
699 enum thermal_notify_event event)
700{
701 guard(thermal_zone)(tz);
702
703 if (thermal_zone_is_present(tz))
704 __thermal_zone_device_update(tz, event);
705}
706EXPORT_SYMBOL_GPL(thermal_zone_device_update);
707
708int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
709 void *data)
710{
711 struct thermal_governor *gov;
712
713 guard(mutex)(&thermal_governor_lock);
714
715 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
716 int ret;
717
718 ret = cb(gov, data);
719 if (ret)
720 return ret;
721 }
722
723 return 0;
724}
725
726int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
727 void *), void *data)
728{
729 struct thermal_cooling_device *cdev;
730
731 guard(mutex)(&thermal_list_lock);
732
733 list_for_each_entry(cdev, &thermal_cdev_list, node) {
734 int ret;
735
736 ret = cb(cdev, data);
737 if (ret)
738 return ret;
739 }
740
741 return 0;
742}
743
744int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
745 void *data)
746{
747 struct thermal_zone_device *tz;
748
749 guard(mutex)(&thermal_list_lock);
750
751 list_for_each_entry(tz, &thermal_tz_list, node) {
752 int ret;
753
754 ret = cb(tz, data);
755 if (ret)
756 return ret;
757 }
758
759 return 0;
760}
761
762struct thermal_zone_device *thermal_zone_get_by_id(int id)
763{
764 struct thermal_zone_device *tz;
765
766 guard(mutex)(&thermal_list_lock);
767
768 list_for_each_entry(tz, &thermal_tz_list, node) {
769 if (tz->id == id) {
770 get_device(&tz->device);
771 return tz;
772 }
773 }
774
775 return NULL;
776}
777
778/*
779 * Device management section: cooling devices, zones devices, and binding
780 *
781 * Set of functions provided by the thermal core for:
782 * - cooling devices lifecycle: registration, unregistration,
783 * binding, and unbinding.
784 * - thermal zone devices lifecycle: registration, unregistration,
785 * binding, and unbinding.
786 */
787
788static int thermal_instance_add(struct thermal_instance *new_instance,
789 struct thermal_cooling_device *cdev,
790 struct thermal_trip_desc *td)
791{
792 struct thermal_instance *instance;
793
794 list_for_each_entry(instance, &td->thermal_instances, trip_node) {
795 if (instance->cdev == cdev)
796 return -EEXIST;
797 }
798
799 list_add_tail(&new_instance->trip_node, &td->thermal_instances);
800
801 guard(cooling_dev)(cdev);
802
803 list_add_tail(&new_instance->cdev_node, &cdev->thermal_instances);
804
805 return 0;
806}
807
808/**
809 * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
810 * @tz: pointer to struct thermal_zone_device
811 * @td: descriptor of the trip point to bind @cdev to
812 * @cdev: pointer to struct thermal_cooling_device
813 * @cool_spec: cooling specification for the trip point and @cdev
814 *
815 * This interface function bind a thermal cooling device to the certain trip
816 * point of a thermal zone device.
817 * This function is usually called in the thermal zone device .bind callback.
818 *
819 * Return: 0 on success, the proper error value otherwise.
820 */
821static int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
822 struct thermal_trip_desc *td,
823 struct thermal_cooling_device *cdev,
824 struct cooling_spec *cool_spec)
825{
826 struct thermal_instance *dev;
827 bool upper_no_limit;
828 int result;
829
830 /* lower default 0, upper default max_state */
831 if (cool_spec->lower == THERMAL_NO_LIMIT)
832 cool_spec->lower = 0;
833
834 if (cool_spec->upper == THERMAL_NO_LIMIT) {
835 cool_spec->upper = cdev->max_state;
836 upper_no_limit = true;
837 } else {
838 upper_no_limit = false;
839 }
840
841 if (cool_spec->lower > cool_spec->upper || cool_spec->upper > cdev->max_state)
842 return -EINVAL;
843
844 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
845 if (!dev)
846 return -ENOMEM;
847
848 dev->cdev = cdev;
849 dev->trip = &td->trip;
850 dev->upper = cool_spec->upper;
851 dev->upper_no_limit = upper_no_limit;
852 dev->lower = cool_spec->lower;
853 dev->target = THERMAL_NO_TARGET;
854 dev->weight = cool_spec->weight;
855
856 result = ida_alloc(&tz->ida, GFP_KERNEL);
857 if (result < 0)
858 goto free_mem;
859
860 dev->id = result;
861 sprintf(dev->name, "cdev%d", dev->id);
862 result =
863 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
864 if (result)
865 goto release_ida;
866
867 snprintf(dev->attr_name, sizeof(dev->attr_name), "cdev%d_trip_point",
868 dev->id);
869 sysfs_attr_init(&dev->attr.attr);
870 dev->attr.attr.name = dev->attr_name;
871 dev->attr.attr.mode = 0444;
872 dev->attr.show = trip_point_show;
873 result = device_create_file(&tz->device, &dev->attr);
874 if (result)
875 goto remove_symbol_link;
876
877 snprintf(dev->weight_attr_name, sizeof(dev->weight_attr_name),
878 "cdev%d_weight", dev->id);
879 sysfs_attr_init(&dev->weight_attr.attr);
880 dev->weight_attr.attr.name = dev->weight_attr_name;
881 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
882 dev->weight_attr.show = weight_show;
883 dev->weight_attr.store = weight_store;
884 result = device_create_file(&tz->device, &dev->weight_attr);
885 if (result)
886 goto remove_trip_file;
887
888 result = thermal_instance_add(dev, cdev, td);
889 if (result)
890 goto remove_weight_file;
891
892 thermal_governor_update_tz(tz, THERMAL_TZ_BIND_CDEV);
893
894 return 0;
895
896remove_weight_file:
897 device_remove_file(&tz->device, &dev->weight_attr);
898remove_trip_file:
899 device_remove_file(&tz->device, &dev->attr);
900remove_symbol_link:
901 sysfs_remove_link(&tz->device.kobj, dev->name);
902release_ida:
903 ida_free(&tz->ida, dev->id);
904free_mem:
905 kfree(dev);
906 return result;
907}
908
909static void thermal_instance_delete(struct thermal_instance *instance)
910{
911 list_del(&instance->trip_node);
912
913 guard(cooling_dev)(instance->cdev);
914
915 list_del(&instance->cdev_node);
916}
917
918/**
919 * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
920 * @tz: pointer to a struct thermal_zone_device.
921 * @td: descriptor of the trip point to unbind @cdev from
922 * @cdev: pointer to a struct thermal_cooling_device.
923 *
924 * This interface function unbind a thermal cooling device from the certain
925 * trip point of a thermal zone device.
926 * This function is usually called in the thermal zone device .unbind callback.
927 */
928static void thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
929 struct thermal_trip_desc *td,
930 struct thermal_cooling_device *cdev)
931{
932 struct thermal_instance *pos, *next;
933
934 list_for_each_entry_safe(pos, next, &td->thermal_instances, trip_node) {
935 if (pos->cdev == cdev) {
936 thermal_instance_delete(pos);
937 goto unbind;
938 }
939 }
940
941 return;
942
943unbind:
944 thermal_governor_update_tz(tz, THERMAL_TZ_UNBIND_CDEV);
945
946 device_remove_file(&tz->device, &pos->weight_attr);
947 device_remove_file(&tz->device, &pos->attr);
948 sysfs_remove_link(&tz->device.kobj, pos->name);
949 ida_free(&tz->ida, pos->id);
950 kfree(pos);
951}
952
953static void thermal_release(struct device *dev)
954{
955 struct thermal_zone_device *tz;
956 struct thermal_cooling_device *cdev;
957
958 if (!strncmp(dev_name(dev), "thermal_zone",
959 sizeof("thermal_zone") - 1)) {
960 tz = to_thermal_zone(dev);
961 thermal_zone_destroy_device_groups(tz);
962 mutex_destroy(&tz->lock);
963 complete(&tz->removal);
964 } else if (!strncmp(dev_name(dev), "cooling_device",
965 sizeof("cooling_device") - 1)) {
966 cdev = to_cooling_device(dev);
967 thermal_cooling_device_destroy_sysfs(cdev);
968 kfree_const(cdev->type);
969 ida_free(&thermal_cdev_ida, cdev->id);
970 kfree(cdev);
971 }
972}
973
974static struct class *thermal_class;
975
976static inline
977void print_bind_err_msg(struct thermal_zone_device *tz,
978 const struct thermal_trip_desc *td,
979 struct thermal_cooling_device *cdev, int ret)
980{
981 dev_err(&tz->device, "binding cdev %s to trip %d failed: %d\n",
982 cdev->type, thermal_zone_trip_id(tz, &td->trip), ret);
983}
984
985static bool __thermal_zone_cdev_bind(struct thermal_zone_device *tz,
986 struct thermal_cooling_device *cdev)
987{
988 struct thermal_trip_desc *td;
989 bool update_tz = false;
990
991 if (!tz->ops.should_bind)
992 return false;
993
994 for_each_trip_desc(tz, td) {
995 struct cooling_spec c = {
996 .upper = THERMAL_NO_LIMIT,
997 .lower = THERMAL_NO_LIMIT,
998 .weight = THERMAL_WEIGHT_DEFAULT
999 };
1000 int ret;
1001
1002 if (!tz->ops.should_bind(tz, &td->trip, cdev, &c))
1003 continue;
1004
1005 ret = thermal_bind_cdev_to_trip(tz, td, cdev, &c);
1006 if (ret) {
1007 print_bind_err_msg(tz, td, cdev, ret);
1008 continue;
1009 }
1010
1011 update_tz = true;
1012 }
1013
1014 return update_tz;
1015}
1016
1017static void thermal_zone_cdev_bind(struct thermal_zone_device *tz,
1018 struct thermal_cooling_device *cdev)
1019{
1020 guard(thermal_zone)(tz);
1021
1022 if (__thermal_zone_cdev_bind(tz, cdev))
1023 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1024}
1025
1026static void thermal_cooling_device_init_complete(struct thermal_cooling_device *cdev)
1027{
1028 struct thermal_zone_device *tz;
1029
1030 guard(mutex)(&thermal_list_lock);
1031
1032 list_add(&cdev->node, &thermal_cdev_list);
1033
1034 list_for_each_entry(tz, &thermal_tz_list, node)
1035 thermal_zone_cdev_bind(tz, cdev);
1036}
1037
1038/**
1039 * __thermal_cooling_device_register() - register a new thermal cooling device
1040 * @np: a pointer to a device tree node.
1041 * @type: the thermal cooling device type.
1042 * @devdata: device private data.
1043 * @ops: standard thermal cooling devices callbacks.
1044 *
1045 * This interface function adds a new thermal cooling device (fan/processor/...)
1046 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1047 * to all the thermal zone devices registered at the same time.
1048 * It also gives the opportunity to link the cooling device to a device tree
1049 * node, so that it can be bound to a thermal zone created out of device tree.
1050 *
1051 * Return: a pointer to the created struct thermal_cooling_device or an
1052 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1053 */
1054static struct thermal_cooling_device *
1055__thermal_cooling_device_register(struct device_node *np,
1056 const char *type, void *devdata,
1057 const struct thermal_cooling_device_ops *ops)
1058{
1059 struct thermal_cooling_device *cdev;
1060 unsigned long current_state;
1061 int id, ret;
1062
1063 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1064 !ops->set_cur_state)
1065 return ERR_PTR(-EINVAL);
1066
1067 if (!thermal_class)
1068 return ERR_PTR(-ENODEV);
1069
1070 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1071 if (!cdev)
1072 return ERR_PTR(-ENOMEM);
1073
1074 ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
1075 if (ret < 0)
1076 goto out_kfree_cdev;
1077 cdev->id = ret;
1078 id = ret;
1079
1080 cdev->type = kstrdup_const(type ? type : "", GFP_KERNEL);
1081 if (!cdev->type) {
1082 ret = -ENOMEM;
1083 goto out_ida_remove;
1084 }
1085
1086 mutex_init(&cdev->lock);
1087 INIT_LIST_HEAD(&cdev->thermal_instances);
1088 cdev->np = np;
1089 cdev->ops = ops;
1090 cdev->updated = false;
1091 cdev->device.class = thermal_class;
1092 cdev->devdata = devdata;
1093
1094 ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
1095 if (ret)
1096 goto out_cdev_type;
1097
1098 /*
1099 * The cooling device's current state is only needed for debug
1100 * initialization below, so a failure to get it does not cause
1101 * the entire cooling device initialization to fail. However,
1102 * the debug will not work for the device if its initial state
1103 * cannot be determined and drivers are responsible for ensuring
1104 * that this will not happen.
1105 */
1106 ret = cdev->ops->get_cur_state(cdev, ¤t_state);
1107 if (ret)
1108 current_state = ULONG_MAX;
1109
1110 thermal_cooling_device_setup_sysfs(cdev);
1111
1112 ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1113 if (ret)
1114 goto out_cooling_dev;
1115
1116 ret = device_register(&cdev->device);
1117 if (ret) {
1118 /* thermal_release() handles rest of the cleanup */
1119 put_device(&cdev->device);
1120 return ERR_PTR(ret);
1121 }
1122
1123 if (current_state <= cdev->max_state)
1124 thermal_debug_cdev_add(cdev, current_state);
1125
1126 thermal_cooling_device_init_complete(cdev);
1127
1128 return cdev;
1129
1130out_cooling_dev:
1131 thermal_cooling_device_destroy_sysfs(cdev);
1132out_cdev_type:
1133 kfree_const(cdev->type);
1134out_ida_remove:
1135 ida_free(&thermal_cdev_ida, id);
1136out_kfree_cdev:
1137 kfree(cdev);
1138 return ERR_PTR(ret);
1139}
1140
1141/**
1142 * thermal_cooling_device_register() - register a new thermal cooling device
1143 * @type: the thermal cooling device type.
1144 * @devdata: device private data.
1145 * @ops: standard thermal cooling devices callbacks.
1146 *
1147 * This interface function adds a new thermal cooling device (fan/processor/...)
1148 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1149 * to all the thermal zone devices registered at the same time.
1150 *
1151 * Return: a pointer to the created struct thermal_cooling_device or an
1152 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1153 */
1154struct thermal_cooling_device *
1155thermal_cooling_device_register(const char *type, void *devdata,
1156 const struct thermal_cooling_device_ops *ops)
1157{
1158 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1159}
1160EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1161
1162/**
1163 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1164 * @np: a pointer to a device tree node.
1165 * @type: the thermal cooling device type.
1166 * @devdata: device private data.
1167 * @ops: standard thermal cooling devices callbacks.
1168 *
1169 * This function will register a cooling device with device tree node reference.
1170 * This interface function adds a new thermal cooling device (fan/processor/...)
1171 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1172 * to all the thermal zone devices registered at the same time.
1173 *
1174 * Return: a pointer to the created struct thermal_cooling_device or an
1175 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1176 */
1177struct thermal_cooling_device *
1178thermal_of_cooling_device_register(struct device_node *np,
1179 const char *type, void *devdata,
1180 const struct thermal_cooling_device_ops *ops)
1181{
1182 return __thermal_cooling_device_register(np, type, devdata, ops);
1183}
1184EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1185
1186static void thermal_cooling_device_release(struct device *dev, void *res)
1187{
1188 thermal_cooling_device_unregister(
1189 *(struct thermal_cooling_device **)res);
1190}
1191
1192/**
1193 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1194 * device
1195 * @dev: a valid struct device pointer of a sensor device.
1196 * @np: a pointer to a device tree node.
1197 * @type: the thermal cooling device type.
1198 * @devdata: device private data.
1199 * @ops: standard thermal cooling devices callbacks.
1200 *
1201 * This function will register a cooling device with device tree node reference.
1202 * This interface function adds a new thermal cooling device (fan/processor/...)
1203 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1204 * to all the thermal zone devices registered at the same time.
1205 *
1206 * Return: a pointer to the created struct thermal_cooling_device or an
1207 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1208 */
1209struct thermal_cooling_device *
1210devm_thermal_of_cooling_device_register(struct device *dev,
1211 struct device_node *np,
1212 const char *type, void *devdata,
1213 const struct thermal_cooling_device_ops *ops)
1214{
1215 struct thermal_cooling_device **ptr, *tcd;
1216
1217 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1218 GFP_KERNEL);
1219 if (!ptr)
1220 return ERR_PTR(-ENOMEM);
1221
1222 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1223 if (IS_ERR(tcd)) {
1224 devres_free(ptr);
1225 return tcd;
1226 }
1227
1228 *ptr = tcd;
1229 devres_add(dev, ptr);
1230
1231 return tcd;
1232}
1233EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1234
1235static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1236{
1237 struct thermal_cooling_device *pos = NULL;
1238
1239 list_for_each_entry(pos, &thermal_cdev_list, node) {
1240 if (pos == cdev)
1241 return true;
1242 }
1243
1244 return false;
1245}
1246
1247/**
1248 * thermal_cooling_device_update - Update a cooling device object
1249 * @cdev: Target cooling device.
1250 *
1251 * Update @cdev to reflect a change of the underlying hardware or platform.
1252 *
1253 * Must be called when the maximum cooling state of @cdev becomes invalid and so
1254 * its .get_max_state() callback needs to be run to produce the new maximum
1255 * cooling state value.
1256 */
1257void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1258{
1259 struct thermal_instance *ti;
1260 unsigned long state;
1261
1262 if (IS_ERR_OR_NULL(cdev))
1263 return;
1264
1265 /*
1266 * Hold thermal_list_lock throughout the update to prevent the device
1267 * from going away while being updated.
1268 */
1269 guard(mutex)(&thermal_list_lock);
1270
1271 if (!thermal_cooling_device_present(cdev))
1272 return;
1273
1274 /*
1275 * Update under the cdev lock to prevent the state from being set beyond
1276 * the new limit concurrently.
1277 */
1278 guard(cooling_dev)(cdev);
1279
1280 if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1281 return;
1282
1283 thermal_cooling_device_stats_reinit(cdev);
1284
1285 list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1286 if (ti->upper == cdev->max_state)
1287 continue;
1288
1289 if (ti->upper < cdev->max_state) {
1290 if (ti->upper_no_limit)
1291 ti->upper = cdev->max_state;
1292
1293 continue;
1294 }
1295
1296 ti->upper = cdev->max_state;
1297 if (ti->lower > ti->upper)
1298 ti->lower = ti->upper;
1299
1300 if (ti->target == THERMAL_NO_TARGET)
1301 continue;
1302
1303 if (ti->target > ti->upper)
1304 ti->target = ti->upper;
1305 }
1306
1307 if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1308 return;
1309
1310 thermal_cooling_device_stats_update(cdev, state);
1311}
1312EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1313
1314static void __thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1315 struct thermal_cooling_device *cdev)
1316{
1317 struct thermal_trip_desc *td;
1318
1319 for_each_trip_desc(tz, td)
1320 thermal_unbind_cdev_from_trip(tz, td, cdev);
1321}
1322
1323static void thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1324 struct thermal_cooling_device *cdev)
1325{
1326 guard(thermal_zone)(tz);
1327
1328 __thermal_zone_cdev_unbind(tz, cdev);
1329}
1330
1331static bool thermal_cooling_device_exit(struct thermal_cooling_device *cdev)
1332{
1333 struct thermal_zone_device *tz;
1334
1335 guard(mutex)(&thermal_list_lock);
1336
1337 if (!thermal_cooling_device_present(cdev))
1338 return false;
1339
1340 list_del(&cdev->node);
1341
1342 list_for_each_entry(tz, &thermal_tz_list, node)
1343 thermal_zone_cdev_unbind(tz, cdev);
1344
1345 return true;
1346}
1347
1348/**
1349 * thermal_cooling_device_unregister() - removes a thermal cooling device
1350 * @cdev: Thermal cooling device to remove.
1351 */
1352void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1353{
1354 if (!cdev)
1355 return;
1356
1357 thermal_debug_cdev_remove(cdev);
1358
1359 if (thermal_cooling_device_exit(cdev))
1360 device_unregister(&cdev->device);
1361}
1362EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1363
1364int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1365{
1366 const struct thermal_trip_desc *td;
1367 int ret = -EINVAL;
1368
1369 if (tz->ops.get_crit_temp)
1370 return tz->ops.get_crit_temp(tz, temp);
1371
1372 guard(thermal_zone)(tz);
1373
1374 for_each_trip_desc(tz, td) {
1375 const struct thermal_trip *trip = &td->trip;
1376
1377 if (trip->type == THERMAL_TRIP_CRITICAL) {
1378 *temp = trip->temperature;
1379 ret = 0;
1380 break;
1381 }
1382 }
1383
1384 return ret;
1385}
1386EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1387
1388static void thermal_zone_device_check(struct work_struct *work)
1389{
1390 struct thermal_zone_device *tz = container_of(work, struct
1391 thermal_zone_device,
1392 poll_queue.work);
1393 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1394}
1395
1396static void thermal_zone_device_init(struct thermal_zone_device *tz)
1397{
1398 struct thermal_trip_desc *td, *next;
1399
1400 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1401
1402 tz->temperature = THERMAL_TEMP_INIT;
1403 tz->passive = 0;
1404 tz->prev_low_trip = -INT_MAX;
1405 tz->prev_high_trip = INT_MAX;
1406 for_each_trip_desc(tz, td) {
1407 struct thermal_instance *instance;
1408
1409 list_for_each_entry(instance, &td->thermal_instances, trip_node)
1410 instance->initialized = false;
1411 }
1412 /*
1413 * At this point, all valid trips need to be moved to trips_high so that
1414 * mitigation can be started if the zone temperature is above them.
1415 */
1416 list_for_each_entry_safe(td, next, &tz->trips_invalid, list_node) {
1417 if (td->trip.temperature != THERMAL_TEMP_INVALID)
1418 move_to_trips_high(tz, td);
1419 }
1420 /* The trips_reached list may not be empty during system resume. */
1421 list_for_each_entry_safe(td, next, &tz->trips_reached, list_node) {
1422 if (td->trip.temperature == THERMAL_TEMP_INVALID)
1423 move_to_trips_invalid(tz, td);
1424 else
1425 move_to_trips_high(tz, td);
1426 }
1427}
1428
1429static int thermal_zone_init_governor(struct thermal_zone_device *tz)
1430{
1431 struct thermal_governor *governor;
1432
1433 guard(mutex)(&thermal_governor_lock);
1434
1435 if (tz->tzp)
1436 governor = __find_governor(tz->tzp->governor_name);
1437 else
1438 governor = def_governor;
1439
1440 return thermal_set_governor(tz, governor);
1441}
1442
1443static void thermal_zone_init_complete(struct thermal_zone_device *tz)
1444{
1445 struct thermal_cooling_device *cdev;
1446
1447 guard(mutex)(&thermal_list_lock);
1448
1449 list_add_tail(&tz->node, &thermal_tz_list);
1450
1451 guard(thermal_zone)(tz);
1452
1453 /* Bind cooling devices for this zone. */
1454 list_for_each_entry(cdev, &thermal_cdev_list, node)
1455 __thermal_zone_cdev_bind(tz, cdev);
1456
1457 tz->state &= ~TZ_STATE_FLAG_INIT;
1458 /*
1459 * If system suspend or resume is in progress at this point, the
1460 * new thermal zone needs to be marked as suspended because
1461 * thermal_pm_notify() has run already.
1462 */
1463 if (thermal_pm_suspended)
1464 tz->state |= TZ_STATE_FLAG_SUSPENDED;
1465
1466 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1467}
1468
1469/**
1470 * thermal_zone_device_register_with_trips() - register a new thermal zone device
1471 * @type: the thermal zone device type
1472 * @trips: a pointer to an array of thermal trips
1473 * @num_trips: the number of trip points the thermal zone support
1474 * @devdata: private device data
1475 * @ops: standard thermal zone device callbacks
1476 * @tzp: thermal zone platform parameters
1477 * @passive_delay: number of milliseconds to wait between polls when
1478 * performing passive cooling
1479 * @polling_delay: number of milliseconds to wait between polls when checking
1480 * whether trip points have been crossed (0 for interrupt
1481 * driven systems)
1482 *
1483 * This interface function adds a new thermal zone device (sensor) to
1484 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1485 * thermal cooling devices registered at the same time.
1486 * thermal_zone_device_unregister() must be called when the device is no
1487 * longer needed. The passive cooling depends on the .get_trend() return value.
1488 *
1489 * Return: a pointer to the created struct thermal_zone_device or an
1490 * in case of error, an ERR_PTR. Caller must check return value with
1491 * IS_ERR*() helpers.
1492 */
1493struct thermal_zone_device *
1494thermal_zone_device_register_with_trips(const char *type,
1495 const struct thermal_trip *trips,
1496 int num_trips, void *devdata,
1497 const struct thermal_zone_device_ops *ops,
1498 const struct thermal_zone_params *tzp,
1499 unsigned int passive_delay,
1500 unsigned int polling_delay)
1501{
1502 const struct thermal_trip *trip = trips;
1503 struct thermal_zone_device *tz;
1504 struct thermal_trip_desc *td;
1505 int id;
1506 int result;
1507
1508 if (!type || strlen(type) == 0) {
1509 pr_err("No thermal zone type defined\n");
1510 return ERR_PTR(-EINVAL);
1511 }
1512
1513 if (strlen(type) >= THERMAL_NAME_LENGTH) {
1514 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1515 type, THERMAL_NAME_LENGTH);
1516 return ERR_PTR(-EINVAL);
1517 }
1518
1519 if (num_trips < 0) {
1520 pr_err("Incorrect number of thermal trips\n");
1521 return ERR_PTR(-EINVAL);
1522 }
1523
1524 if (!ops || !ops->get_temp) {
1525 pr_err("Thermal zone device ops not defined or invalid\n");
1526 return ERR_PTR(-EINVAL);
1527 }
1528
1529 if (num_trips > 0 && !trips)
1530 return ERR_PTR(-EINVAL);
1531
1532 if (polling_delay && passive_delay > polling_delay)
1533 return ERR_PTR(-EINVAL);
1534
1535 if (!thermal_class)
1536 return ERR_PTR(-ENODEV);
1537
1538 tz = kzalloc(struct_size(tz, trips, num_trips), GFP_KERNEL);
1539 if (!tz)
1540 return ERR_PTR(-ENOMEM);
1541
1542 if (tzp) {
1543 tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1544 if (!tz->tzp) {
1545 result = -ENOMEM;
1546 goto free_tz;
1547 }
1548 }
1549
1550 INIT_LIST_HEAD(&tz->node);
1551 INIT_LIST_HEAD(&tz->trips_high);
1552 INIT_LIST_HEAD(&tz->trips_reached);
1553 INIT_LIST_HEAD(&tz->trips_invalid);
1554 ida_init(&tz->ida);
1555 mutex_init(&tz->lock);
1556 init_completion(&tz->removal);
1557 init_completion(&tz->resume);
1558 id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1559 if (id < 0) {
1560 result = id;
1561 goto free_tzp;
1562 }
1563
1564 tz->id = id;
1565 strscpy(tz->type, type, sizeof(tz->type));
1566
1567 tz->ops = *ops;
1568 if (!tz->ops.critical)
1569 tz->ops.critical = thermal_zone_device_critical;
1570
1571 tz->device.class = thermal_class;
1572 tz->devdata = devdata;
1573 tz->num_trips = num_trips;
1574 for_each_trip_desc(tz, td) {
1575 td->trip = *trip++;
1576 INIT_LIST_HEAD(&td->thermal_instances);
1577 INIT_LIST_HEAD(&td->list_node);
1578 /*
1579 * Mark all thresholds as invalid to start with even though
1580 * this only matters for the trips that start as invalid and
1581 * become valid later.
1582 */
1583 move_to_trips_invalid(tz, td);
1584 }
1585
1586 tz->polling_delay_jiffies = msecs_to_jiffies(polling_delay);
1587 tz->passive_delay_jiffies = msecs_to_jiffies(passive_delay);
1588 tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
1589
1590 tz->state = TZ_STATE_FLAG_INIT;
1591
1592 /* sys I/F */
1593 /* Add nodes that are always present via .groups */
1594 result = thermal_zone_create_device_groups(tz);
1595 if (result)
1596 goto remove_id;
1597
1598 result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1599 if (result) {
1600 thermal_zone_destroy_device_groups(tz);
1601 goto remove_id;
1602 }
1603 thermal_zone_device_init(tz);
1604 result = device_register(&tz->device);
1605 if (result)
1606 goto release_device;
1607
1608 result = thermal_zone_init_governor(tz);
1609 if (result)
1610 goto unregister;
1611
1612 if (!tz->tzp || !tz->tzp->no_hwmon) {
1613 result = thermal_add_hwmon_sysfs(tz);
1614 if (result)
1615 goto unregister;
1616 }
1617
1618 result = thermal_thresholds_init(tz);
1619 if (result)
1620 goto remove_hwmon;
1621
1622 thermal_zone_init_complete(tz);
1623
1624 thermal_notify_tz_create(tz);
1625
1626 thermal_debug_tz_add(tz);
1627
1628 return tz;
1629
1630remove_hwmon:
1631 thermal_remove_hwmon_sysfs(tz);
1632unregister:
1633 device_del(&tz->device);
1634release_device:
1635 put_device(&tz->device);
1636remove_id:
1637 ida_free(&thermal_tz_ida, id);
1638free_tzp:
1639 kfree(tz->tzp);
1640free_tz:
1641 kfree(tz);
1642 return ERR_PTR(result);
1643}
1644EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1645
1646struct thermal_zone_device *thermal_tripless_zone_device_register(
1647 const char *type,
1648 void *devdata,
1649 const struct thermal_zone_device_ops *ops,
1650 const struct thermal_zone_params *tzp)
1651{
1652 return thermal_zone_device_register_with_trips(type, NULL, 0, devdata,
1653 ops, tzp, 0, 0);
1654}
1655EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1656
1657void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1658{
1659 return tzd->devdata;
1660}
1661EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1662
1663const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1664{
1665 return tzd->type;
1666}
1667EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1668
1669int thermal_zone_device_id(struct thermal_zone_device *tzd)
1670{
1671 return tzd->id;
1672}
1673EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1674
1675struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1676{
1677 return &tzd->device;
1678}
1679EXPORT_SYMBOL_GPL(thermal_zone_device);
1680
1681static bool thermal_zone_exit(struct thermal_zone_device *tz)
1682{
1683 struct thermal_cooling_device *cdev;
1684
1685 guard(mutex)(&thermal_list_lock);
1686
1687 if (list_empty(&tz->node))
1688 return false;
1689
1690 guard(thermal_zone)(tz);
1691
1692 tz->state |= TZ_STATE_FLAG_EXIT;
1693 list_del_init(&tz->node);
1694
1695 /* Unbind all cdevs associated with this thermal zone. */
1696 list_for_each_entry(cdev, &thermal_cdev_list, node)
1697 __thermal_zone_cdev_unbind(tz, cdev);
1698
1699 return true;
1700}
1701
1702/**
1703 * thermal_zone_device_unregister - removes the registered thermal zone device
1704 * @tz: the thermal zone device to remove
1705 */
1706void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1707{
1708 if (!tz)
1709 return;
1710
1711 thermal_debug_tz_remove(tz);
1712
1713 if (!thermal_zone_exit(tz))
1714 return;
1715
1716 cancel_delayed_work_sync(&tz->poll_queue);
1717
1718 thermal_set_governor(tz, NULL);
1719
1720 thermal_thresholds_exit(tz);
1721 thermal_remove_hwmon_sysfs(tz);
1722 ida_free(&thermal_tz_ida, tz->id);
1723 ida_destroy(&tz->ida);
1724
1725 device_del(&tz->device);
1726 put_device(&tz->device);
1727
1728 thermal_notify_tz_delete(tz);
1729
1730 wait_for_completion(&tz->removal);
1731 kfree(tz->tzp);
1732 kfree(tz);
1733}
1734EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1735
1736/**
1737 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1738 * @name: thermal zone name to fetch the temperature
1739 *
1740 * When only one zone is found with the passed name, returns a reference to it.
1741 *
1742 * Return: On success returns a reference to an unique thermal zone with
1743 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1744 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1745 */
1746struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1747{
1748 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1749 unsigned int found = 0;
1750
1751 if (!name)
1752 return ERR_PTR(-EINVAL);
1753
1754 guard(mutex)(&thermal_list_lock);
1755
1756 list_for_each_entry(pos, &thermal_tz_list, node)
1757 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1758 found++;
1759 ref = pos;
1760 }
1761
1762 if (!found)
1763 return ERR_PTR(-ENODEV);
1764
1765 /* Success only when one zone is found. */
1766 if (found > 1)
1767 return ERR_PTR(-EEXIST);
1768
1769 return ref;
1770}
1771EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1772
1773static void thermal_zone_device_resume(struct work_struct *work)
1774{
1775 struct thermal_zone_device *tz;
1776
1777 tz = container_of(work, struct thermal_zone_device, poll_queue.work);
1778
1779 guard(thermal_zone)(tz);
1780
1781 tz->state &= ~(TZ_STATE_FLAG_SUSPENDED | TZ_STATE_FLAG_RESUMING);
1782
1783 thermal_debug_tz_resume(tz);
1784 thermal_zone_device_init(tz);
1785 thermal_governor_update_tz(tz, THERMAL_TZ_RESUME);
1786 __thermal_zone_device_update(tz, THERMAL_TZ_RESUME);
1787
1788 complete(&tz->resume);
1789}
1790
1791static void thermal_zone_pm_prepare(struct thermal_zone_device *tz)
1792{
1793 guard(thermal_zone)(tz);
1794
1795 if (tz->state & TZ_STATE_FLAG_RESUMING) {
1796 /*
1797 * thermal_zone_device_resume() queued up for this zone has not
1798 * acquired the lock yet, so release it to let the function run
1799 * and wait util it has done the work.
1800 */
1801 scoped_guard(thermal_zone_reverse, tz) {
1802 wait_for_completion(&tz->resume);
1803 }
1804 }
1805
1806 tz->state |= TZ_STATE_FLAG_SUSPENDED;
1807}
1808
1809static void thermal_pm_notify_prepare(void)
1810{
1811 struct thermal_zone_device *tz;
1812
1813 guard(mutex)(&thermal_list_lock);
1814
1815 thermal_pm_suspended = true;
1816
1817 list_for_each_entry(tz, &thermal_tz_list, node)
1818 thermal_zone_pm_prepare(tz);
1819}
1820
1821static void thermal_zone_pm_complete(struct thermal_zone_device *tz)
1822{
1823 guard(thermal_zone)(tz);
1824
1825 cancel_delayed_work(&tz->poll_queue);
1826
1827 reinit_completion(&tz->resume);
1828 tz->state |= TZ_STATE_FLAG_RESUMING;
1829
1830 /*
1831 * Replace the work function with the resume one, which will restore the
1832 * original work function and schedule the polling work if needed.
1833 */
1834 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_resume);
1835 /* Queue up the work without a delay. */
1836 mod_delayed_work(system_freezable_power_efficient_wq, &tz->poll_queue, 0);
1837}
1838
1839static void thermal_pm_notify_complete(void)
1840{
1841 struct thermal_zone_device *tz;
1842
1843 guard(mutex)(&thermal_list_lock);
1844
1845 thermal_pm_suspended = false;
1846
1847 list_for_each_entry(tz, &thermal_tz_list, node)
1848 thermal_zone_pm_complete(tz);
1849}
1850
1851static int thermal_pm_notify(struct notifier_block *nb,
1852 unsigned long mode, void *_unused)
1853{
1854 switch (mode) {
1855 case PM_HIBERNATION_PREPARE:
1856 case PM_RESTORE_PREPARE:
1857 case PM_SUSPEND_PREPARE:
1858 thermal_pm_notify_prepare();
1859 break;
1860 case PM_POST_HIBERNATION:
1861 case PM_POST_RESTORE:
1862 case PM_POST_SUSPEND:
1863 thermal_pm_notify_complete();
1864 break;
1865 default:
1866 break;
1867 }
1868 return 0;
1869}
1870
1871static struct notifier_block thermal_pm_nb = {
1872 .notifier_call = thermal_pm_notify,
1873 /*
1874 * Run at the lowest priority to avoid interference between the thermal
1875 * zone resume work items spawned by thermal_pm_notify() and the other
1876 * PM notifiers.
1877 */
1878 .priority = INT_MIN,
1879};
1880
1881static int __init thermal_init(void)
1882{
1883 int result;
1884
1885 thermal_debug_init();
1886
1887 result = thermal_netlink_init();
1888 if (result)
1889 goto error;
1890
1891 result = thermal_register_governors();
1892 if (result)
1893 goto unregister_netlink;
1894
1895 thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1896 if (!thermal_class) {
1897 result = -ENOMEM;
1898 goto unregister_governors;
1899 }
1900
1901 thermal_class->name = "thermal";
1902 thermal_class->dev_release = thermal_release;
1903
1904 result = class_register(thermal_class);
1905 if (result) {
1906 kfree(thermal_class);
1907 thermal_class = NULL;
1908 goto unregister_governors;
1909 }
1910
1911 result = register_pm_notifier(&thermal_pm_nb);
1912 if (result)
1913 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1914 result);
1915
1916 return 0;
1917
1918unregister_governors:
1919 thermal_unregister_governors();
1920unregister_netlink:
1921 thermal_netlink_exit();
1922error:
1923 mutex_destroy(&thermal_list_lock);
1924 mutex_destroy(&thermal_governor_lock);
1925 return result;
1926}
1927postcore_initcall(thermal_init);