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(s1: name, s2: 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, failed_gov_name: 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)(T: &thermal_governor_lock);
127
128 err = -EBUSY;
129 if (!__find_governor(name: governor->name)) {
130 bool match_default;
131
132 err = 0;
133 list_add(new: &governor->governor_list, head: &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)(T: &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(s1: name, s2: governor->name, THERMAL_NAME_LENGTH)) {
155 int ret;
156
157 ret = thermal_set_governor(tz: pos, new_gov: 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)(T: &thermal_governor_lock);
176
177 if (!__find_governor(name: governor->name))
178 return;
179
180 list_del(entry: &governor->governor_list);
181
182 guard(mutex)(T: &thermal_list_lock);
183
184 list_for_each_entry(pos, &thermal_tz_list, node) {
185 if (!strncasecmp(s1: pos->governor->name, s2: governor->name,
186 THERMAL_NAME_LENGTH))
187 thermal_set_governor(tz: 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)(T: &thermal_governor_lock);
198 guard(thermal_zone)(T: tz);
199
200 gov = __find_governor(name: strim(policy));
201 if (gov)
202 ret = thermal_set_governor(tz, new_gov: gov);
203
204 thermal_notify_tz_gov_change(tz, name: 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)(T: &thermal_governor_lock);
215
216 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
217 count += sysfs_emit_at(buf, at: count, fmt: "%s ", pos->name);
218 }
219 count += sysfs_emit_at(buf, at: count, fmt: "\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: *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: *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(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, mode: 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(j: delay);
315
316 mod_delayed_work(wq: system_freezable_power_efficient_wq, dwork: &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, delay: 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, delay: tz->passive_delay_jiffies);
351 else if (tz->polling_delay_jiffies)
352 thermal_zone_device_set_polling(tz, delay: 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,
373 enum hw_protection_action action)
374{
375 /*
376 * poweroff_delay_ms must be a carefully profiled positive value.
377 * Its a must for forced_emergency_poweroff_work to be scheduled.
378 */
379 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
380 const char *msg = "Temperature too high";
381
382 dev_emerg(&tz->device, "%s: critical temperature reached\n", tz->type);
383
384 __hw_protection_trigger(reason: msg, ms_until_forced: poweroff_delay_ms, action);
385}
386
387void thermal_zone_device_critical(struct thermal_zone_device *tz)
388{
389 thermal_zone_device_halt(tz, action: HWPROT_ACT_DEFAULT);
390}
391EXPORT_SYMBOL(thermal_zone_device_critical);
392
393void thermal_zone_device_critical_shutdown(struct thermal_zone_device *tz)
394{
395 thermal_zone_device_halt(tz, action: HWPROT_ACT_SHUTDOWN);
396}
397
398void thermal_zone_device_critical_reboot(struct thermal_zone_device *tz)
399{
400 thermal_zone_device_halt(tz, action: HWPROT_ACT_REBOOT);
401}
402
403static void handle_critical_trips(struct thermal_zone_device *tz,
404 const struct thermal_trip *trip)
405{
406 trace_thermal_zone_trip(tz, trip: thermal_zone_trip_id(tz, trip), trip_type: trip->type);
407
408 if (trip->type == THERMAL_TRIP_CRITICAL)
409 tz->ops.critical(tz);
410 else if (tz->ops.hot)
411 tz->ops.hot(tz);
412}
413
414static void move_trip_to_sorted_list(struct thermal_trip_desc *td,
415 struct list_head *list)
416{
417 struct thermal_trip_desc *entry;
418
419 /*
420 * Delete upfront and then add to make relocation within the same list
421 * work.
422 */
423 list_del(entry: &td->list_node);
424
425 /* Assume that the new entry is likely to be the last one. */
426 list_for_each_entry_reverse(entry, list, list_node) {
427 if (entry->threshold <= td->threshold) {
428 list_add(new: &td->list_node, head: &entry->list_node);
429 return;
430 }
431 }
432 list_add(new: &td->list_node, head: list);
433}
434
435static void move_to_trips_high(struct thermal_zone_device *tz,
436 struct thermal_trip_desc *td)
437{
438 td->threshold = td->trip.temperature;
439 move_trip_to_sorted_list(td, list: &tz->trips_high);
440}
441
442static void move_to_trips_reached(struct thermal_zone_device *tz,
443 struct thermal_trip_desc *td)
444{
445 td->threshold = td->trip.temperature - td->trip.hysteresis;
446 move_trip_to_sorted_list(td, list: &tz->trips_reached);
447}
448
449static void move_to_trips_invalid(struct thermal_zone_device *tz,
450 struct thermal_trip_desc *td)
451{
452 td->threshold = INT_MAX;
453 list_move(list: &td->list_node, head: &tz->trips_invalid);
454}
455
456static void thermal_governor_trip_crossed(struct thermal_governor *governor,
457 struct thermal_zone_device *tz,
458 const struct thermal_trip *trip,
459 bool upward)
460{
461 if (trip->type == THERMAL_TRIP_HOT || trip->type == THERMAL_TRIP_CRITICAL)
462 return;
463
464 if (governor->trip_crossed)
465 governor->trip_crossed(tz, trip, upward);
466}
467
468static void thermal_trip_crossed(struct thermal_zone_device *tz,
469 struct thermal_trip_desc *td,
470 struct thermal_governor *governor,
471 bool upward)
472{
473 const struct thermal_trip *trip = &td->trip;
474
475 if (upward) {
476 if (trip->type == THERMAL_TRIP_PASSIVE)
477 tz->passive++;
478 else if (trip->type == THERMAL_TRIP_CRITICAL ||
479 trip->type == THERMAL_TRIP_HOT)
480 handle_critical_trips(tz, trip);
481
482 thermal_notify_tz_trip_up(tz, trip);
483 thermal_debug_tz_trip_up(tz, trip);
484 } else {
485 if (trip->type == THERMAL_TRIP_PASSIVE) {
486 tz->passive--;
487 WARN_ON(tz->passive < 0);
488 }
489 thermal_notify_tz_trip_down(tz, trip);
490 thermal_debug_tz_trip_down(tz, trip);
491 }
492 thermal_governor_trip_crossed(governor, tz, trip, upward);
493}
494
495void thermal_zone_set_trip_hyst(struct thermal_zone_device *tz,
496 struct thermal_trip *trip, int hyst)
497{
498 struct thermal_trip_desc *td = trip_to_trip_desc(trip);
499
500 WRITE_ONCE(trip->hysteresis, hyst);
501 thermal_notify_tz_trip_change(tz, trip);
502 /*
503 * If the zone temperature is above or at the trip tmperature, the trip
504 * is in the trips_reached list and its threshold is equal to its low
505 * temperature. It needs to stay in that list, but its threshold needs
506 * to be updated and the list ordering may need to be restored.
507 */
508 if (tz->temperature >= td->threshold)
509 move_to_trips_reached(tz, td);
510}
511
512void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
513 struct thermal_trip *trip, int temp)
514{
515 struct thermal_trip_desc *td = trip_to_trip_desc(trip);
516 int old_temp = trip->temperature;
517
518 if (old_temp == temp)
519 return;
520
521 WRITE_ONCE(trip->temperature, temp);
522 thermal_notify_tz_trip_change(tz, trip);
523
524 if (old_temp == THERMAL_TEMP_INVALID) {
525 /*
526 * The trip was invalid before the change, so move it to the
527 * trips_high list regardless of the new temperature value
528 * because there is no mitigation under way for it. If a
529 * mitigation needs to be started, the trip will be moved to the
530 * trips_reached list later.
531 */
532 move_to_trips_high(tz, td);
533 return;
534 }
535
536 if (temp == THERMAL_TEMP_INVALID) {
537 /*
538 * If the trip is in the trips_reached list, mitigation is under
539 * way for it and it needs to be stopped because the trip is
540 * effectively going away.
541 */
542 if (tz->temperature >= td->threshold)
543 thermal_trip_crossed(tz, td, governor: thermal_get_tz_governor(tz), upward: false);
544
545 move_to_trips_invalid(tz, td);
546 return;
547 }
548
549 /*
550 * The trip stays on its current list, but its threshold needs to be
551 * updated due to the temperature change and the list ordering may need
552 * to be restored.
553 */
554 if (tz->temperature >= td->threshold)
555 move_to_trips_reached(tz, td);
556 else
557 move_to_trips_high(tz, td);
558}
559EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
560
561static void thermal_zone_handle_trips(struct thermal_zone_device *tz,
562 struct thermal_governor *governor,
563 int *low, int *high)
564{
565 struct thermal_trip_desc *td, *next;
566 LIST_HEAD(way_down_list);
567
568 /* Check the trips that were below or at the zone temperature. */
569 list_for_each_entry_safe_reverse(td, next, &tz->trips_reached, list_node) {
570 if (td->threshold <= tz->temperature)
571 break;
572
573 thermal_trip_crossed(tz, td, governor, upward: false);
574 /*
575 * The current trips_high list needs to be processed before
576 * adding new entries to it, so put them on a temporary list.
577 */
578 list_move(list: &td->list_node, head: &way_down_list);
579 }
580 /* Check the trips that were previously above the zone temperature. */
581 list_for_each_entry_safe(td, next, &tz->trips_high, list_node) {
582 if (td->threshold > tz->temperature)
583 break;
584
585 thermal_trip_crossed(tz, td, governor, upward: true);
586 move_to_trips_reached(tz, td);
587 }
588 /* Move all of the trips from the temporary list to trips_high. */
589 list_for_each_entry_safe(td, next, &way_down_list, list_node)
590 move_to_trips_high(tz, td);
591
592 if (!list_empty(head: &tz->trips_reached)) {
593 td = list_last_entry(&tz->trips_reached,
594 struct thermal_trip_desc, list_node);
595 /*
596 * Set the "low" value below the current trip threshold in case
597 * the zone temperature is at that threshold and stays there,
598 * which would trigger a new interrupt immediately in vain.
599 */
600 *low = td->threshold - 1;
601 }
602 if (!list_empty(head: &tz->trips_high)) {
603 td = list_first_entry(&tz->trips_high,
604 struct thermal_trip_desc, list_node);
605 *high = td->threshold;
606 }
607}
608
609void __thermal_zone_device_update(struct thermal_zone_device *tz,
610 enum thermal_notify_event event)
611{
612 struct thermal_governor *governor = thermal_get_tz_governor(tz);
613 int low = -INT_MAX, high = INT_MAX;
614 int temp, ret;
615
616 if (tz->state != TZ_STATE_READY || tz->mode != THERMAL_DEVICE_ENABLED)
617 return;
618
619 ret = __thermal_zone_get_temp(tz, temp: &temp);
620 if (ret) {
621 thermal_zone_recheck(tz, error: ret);
622 return;
623 } else if (temp <= THERMAL_TEMP_INVALID) {
624 /*
625 * Special case: No valid temperature value is available, but
626 * the zone owner does not want the core to do anything about
627 * it. Continue regular zone polling if needed, so that this
628 * function can be called again, but skip everything else.
629 */
630 goto monitor;
631 }
632
633 tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
634
635 tz->last_temperature = tz->temperature;
636 tz->temperature = temp;
637
638 trace_thermal_temperature(tz);
639
640 thermal_genl_sampling_temp(id: tz->id, temp);
641
642 tz->notify_event = event;
643
644 thermal_zone_handle_trips(tz, governor, low: &low, high: &high);
645
646 thermal_thresholds_handle(tz, low: &low, high: &high);
647
648 thermal_zone_set_trips(tz, low, high);
649
650 if (governor->manage)
651 governor->manage(tz);
652
653 thermal_debug_update_trip_stats(tz);
654
655monitor:
656 monitor_thermal_zone(tz);
657}
658
659static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
660 enum thermal_device_mode mode)
661{
662 int ret;
663
664 guard(thermal_zone)(T: tz);
665
666 /* do nothing if mode isn't changing */
667 if (mode == tz->mode)
668 return 0;
669
670 ret = __thermal_zone_device_set_mode(tz, mode);
671 if (ret)
672 return ret;
673
674 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
675
676 if (mode == THERMAL_DEVICE_ENABLED)
677 thermal_notify_tz_enable(tz);
678 else
679 thermal_notify_tz_disable(tz);
680
681 return 0;
682}
683
684int thermal_zone_device_enable(struct thermal_zone_device *tz)
685{
686 return thermal_zone_device_set_mode(tz, mode: THERMAL_DEVICE_ENABLED);
687}
688EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
689
690int thermal_zone_device_disable(struct thermal_zone_device *tz)
691{
692 return thermal_zone_device_set_mode(tz, mode: THERMAL_DEVICE_DISABLED);
693}
694EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
695
696static bool thermal_zone_is_present(struct thermal_zone_device *tz)
697{
698 return !list_empty(head: &tz->node);
699}
700
701void thermal_zone_device_update(struct thermal_zone_device *tz,
702 enum thermal_notify_event event)
703{
704 guard(thermal_zone)(T: tz);
705
706 if (thermal_zone_is_present(tz))
707 __thermal_zone_device_update(tz, event);
708}
709EXPORT_SYMBOL_GPL(thermal_zone_device_update);
710
711int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
712 void *data)
713{
714 struct thermal_governor *gov;
715
716 guard(mutex)(T: &thermal_governor_lock);
717
718 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
719 int ret;
720
721 ret = cb(gov, data);
722 if (ret)
723 return ret;
724 }
725
726 return 0;
727}
728
729int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
730 void *), void *data)
731{
732 struct thermal_cooling_device *cdev;
733
734 guard(mutex)(T: &thermal_list_lock);
735
736 list_for_each_entry(cdev, &thermal_cdev_list, node) {
737 int ret;
738
739 ret = cb(cdev, data);
740 if (ret)
741 return ret;
742 }
743
744 return 0;
745}
746
747int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
748 void *data)
749{
750 struct thermal_zone_device *tz;
751
752 guard(mutex)(T: &thermal_list_lock);
753
754 list_for_each_entry(tz, &thermal_tz_list, node) {
755 int ret;
756
757 ret = cb(tz, data);
758 if (ret)
759 return ret;
760 }
761
762 return 0;
763}
764
765struct thermal_zone_device *thermal_zone_get_by_id(int id)
766{
767 struct thermal_zone_device *tz;
768
769 guard(mutex)(T: &thermal_list_lock);
770
771 list_for_each_entry(tz, &thermal_tz_list, node) {
772 if (tz->id == id) {
773 get_device(dev: &tz->device);
774 return tz;
775 }
776 }
777
778 return NULL;
779}
780
781/*
782 * Device management section: cooling devices, zones devices, and binding
783 *
784 * Set of functions provided by the thermal core for:
785 * - cooling devices lifecycle: registration, unregistration,
786 * binding, and unbinding.
787 * - thermal zone devices lifecycle: registration, unregistration,
788 * binding, and unbinding.
789 */
790
791static int thermal_instance_add(struct thermal_instance *new_instance,
792 struct thermal_cooling_device *cdev,
793 struct thermal_trip_desc *td)
794{
795 struct thermal_instance *instance;
796
797 list_for_each_entry(instance, &td->thermal_instances, trip_node) {
798 if (instance->cdev == cdev)
799 return -EEXIST;
800 }
801
802 list_add_tail(new: &new_instance->trip_node, head: &td->thermal_instances);
803
804 guard(cooling_dev)(T: cdev);
805
806 list_add_tail(new: &new_instance->cdev_node, head: &cdev->thermal_instances);
807
808 return 0;
809}
810
811/**
812 * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
813 * @tz: pointer to struct thermal_zone_device
814 * @td: descriptor of the trip point to bind @cdev to
815 * @cdev: pointer to struct thermal_cooling_device
816 * @cool_spec: cooling specification for the trip point and @cdev
817 *
818 * This interface function bind a thermal cooling device to the certain trip
819 * point of a thermal zone device.
820 * This function is usually called in the thermal zone device .bind callback.
821 *
822 * Return: 0 on success, the proper error value otherwise.
823 */
824static int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
825 struct thermal_trip_desc *td,
826 struct thermal_cooling_device *cdev,
827 struct cooling_spec *cool_spec)
828{
829 struct thermal_instance *dev;
830 bool upper_no_limit;
831 int result;
832
833 /* lower default 0, upper default max_state */
834 if (cool_spec->lower == THERMAL_NO_LIMIT)
835 cool_spec->lower = 0;
836
837 if (cool_spec->upper == THERMAL_NO_LIMIT) {
838 cool_spec->upper = cdev->max_state;
839 upper_no_limit = true;
840 } else {
841 upper_no_limit = false;
842 }
843
844 if (cool_spec->lower > cool_spec->upper || cool_spec->upper > cdev->max_state)
845 return -EINVAL;
846
847 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
848 if (!dev)
849 return -ENOMEM;
850
851 dev->cdev = cdev;
852 dev->trip = &td->trip;
853 dev->upper = cool_spec->upper;
854 dev->upper_no_limit = upper_no_limit;
855 dev->lower = cool_spec->lower;
856 dev->target = THERMAL_NO_TARGET;
857 dev->weight = cool_spec->weight;
858
859 result = ida_alloc(ida: &tz->ida, GFP_KERNEL);
860 if (result < 0)
861 goto free_mem;
862
863 dev->id = result;
864 sprintf(buf: dev->name, fmt: "cdev%d", dev->id);
865 result =
866 sysfs_create_link(kobj: &tz->device.kobj, target: &cdev->device.kobj, name: dev->name);
867 if (result)
868 goto release_ida;
869
870 snprintf(buf: dev->attr_name, size: sizeof(dev->attr_name), fmt: "cdev%d_trip_point",
871 dev->id);
872 sysfs_attr_init(&dev->attr.attr);
873 dev->attr.attr.name = dev->attr_name;
874 dev->attr.attr.mode = 0444;
875 dev->attr.show = trip_point_show;
876 result = device_create_file(device: &tz->device, entry: &dev->attr);
877 if (result)
878 goto remove_symbol_link;
879
880 snprintf(buf: dev->weight_attr_name, size: sizeof(dev->weight_attr_name),
881 fmt: "cdev%d_weight", dev->id);
882 sysfs_attr_init(&dev->weight_attr.attr);
883 dev->weight_attr.attr.name = dev->weight_attr_name;
884 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
885 dev->weight_attr.show = weight_show;
886 dev->weight_attr.store = weight_store;
887 result = device_create_file(device: &tz->device, entry: &dev->weight_attr);
888 if (result)
889 goto remove_trip_file;
890
891 result = thermal_instance_add(new_instance: dev, cdev, td);
892 if (result)
893 goto remove_weight_file;
894
895 thermal_governor_update_tz(tz, reason: THERMAL_TZ_BIND_CDEV);
896
897 return 0;
898
899remove_weight_file:
900 device_remove_file(dev: &tz->device, attr: &dev->weight_attr);
901remove_trip_file:
902 device_remove_file(dev: &tz->device, attr: &dev->attr);
903remove_symbol_link:
904 sysfs_remove_link(kobj: &tz->device.kobj, name: dev->name);
905release_ida:
906 ida_free(&tz->ida, id: dev->id);
907free_mem:
908 kfree(objp: dev);
909 return result;
910}
911
912static void thermal_instance_delete(struct thermal_instance *instance)
913{
914 list_del(entry: &instance->trip_node);
915
916 guard(cooling_dev)(T: instance->cdev);
917
918 list_del(entry: &instance->cdev_node);
919}
920
921/**
922 * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
923 * @tz: pointer to a struct thermal_zone_device.
924 * @td: descriptor of the trip point to unbind @cdev from
925 * @cdev: pointer to a struct thermal_cooling_device.
926 *
927 * This interface function unbind a thermal cooling device from the certain
928 * trip point of a thermal zone device.
929 * This function is usually called in the thermal zone device .unbind callback.
930 */
931static void thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
932 struct thermal_trip_desc *td,
933 struct thermal_cooling_device *cdev)
934{
935 struct thermal_instance *pos, *next;
936
937 list_for_each_entry_safe(pos, next, &td->thermal_instances, trip_node) {
938 if (pos->cdev == cdev) {
939 thermal_instance_delete(instance: pos);
940 goto unbind;
941 }
942 }
943
944 return;
945
946unbind:
947 thermal_governor_update_tz(tz, reason: THERMAL_TZ_UNBIND_CDEV);
948
949 device_remove_file(dev: &tz->device, attr: &pos->weight_attr);
950 device_remove_file(dev: &tz->device, attr: &pos->attr);
951 sysfs_remove_link(kobj: &tz->device.kobj, name: pos->name);
952 ida_free(&tz->ida, id: pos->id);
953 kfree(objp: pos);
954}
955
956static void thermal_release(struct device *dev)
957{
958 struct thermal_zone_device *tz;
959 struct thermal_cooling_device *cdev;
960
961 if (!strncmp(dev_name(dev), "thermal_zone",
962 sizeof("thermal_zone") - 1)) {
963 tz = to_thermal_zone(dev);
964 thermal_zone_destroy_device_groups(tz);
965 mutex_destroy(lock: &tz->lock);
966 complete(&tz->removal);
967 } else if (!strncmp(dev_name(dev), "cooling_device",
968 sizeof("cooling_device") - 1)) {
969 cdev = to_cooling_device(dev);
970 thermal_cooling_device_destroy_sysfs(cdev);
971 kfree_const(x: cdev->type);
972 ida_free(&thermal_cdev_ida, id: cdev->id);
973 kfree(objp: cdev);
974 }
975}
976
977static struct class *thermal_class;
978
979static inline
980void print_bind_err_msg(struct thermal_zone_device *tz,
981 const struct thermal_trip_desc *td,
982 struct thermal_cooling_device *cdev, int ret)
983{
984 dev_err(&tz->device, "binding cdev %s to trip %d failed: %d\n",
985 cdev->type, thermal_zone_trip_id(tz, &td->trip), ret);
986}
987
988static bool __thermal_zone_cdev_bind(struct thermal_zone_device *tz,
989 struct thermal_cooling_device *cdev)
990{
991 struct thermal_trip_desc *td;
992 bool update_tz = false;
993
994 if (!tz->ops.should_bind)
995 return false;
996
997 for_each_trip_desc(tz, td) {
998 struct cooling_spec c = {
999 .upper = THERMAL_NO_LIMIT,
1000 .lower = THERMAL_NO_LIMIT,
1001 .weight = THERMAL_WEIGHT_DEFAULT
1002 };
1003 int ret;
1004
1005 if (!tz->ops.should_bind(tz, &td->trip, cdev, &c))
1006 continue;
1007
1008 ret = thermal_bind_cdev_to_trip(tz, td, cdev, cool_spec: &c);
1009 if (ret) {
1010 print_bind_err_msg(tz, td, cdev, ret);
1011 continue;
1012 }
1013
1014 update_tz = true;
1015 }
1016
1017 return update_tz;
1018}
1019
1020static void thermal_zone_cdev_bind(struct thermal_zone_device *tz,
1021 struct thermal_cooling_device *cdev)
1022{
1023 guard(thermal_zone)(T: tz);
1024
1025 if (__thermal_zone_cdev_bind(tz, cdev))
1026 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
1027}
1028
1029static void thermal_cooling_device_init_complete(struct thermal_cooling_device *cdev)
1030{
1031 struct thermal_zone_device *tz;
1032
1033 guard(mutex)(T: &thermal_list_lock);
1034
1035 list_add(new: &cdev->node, head: &thermal_cdev_list);
1036
1037 list_for_each_entry(tz, &thermal_tz_list, node)
1038 thermal_zone_cdev_bind(tz, cdev);
1039}
1040
1041/**
1042 * __thermal_cooling_device_register() - register a new thermal cooling device
1043 * @np: a pointer to a device tree node.
1044 * @type: the thermal cooling device type.
1045 * @devdata: device private data.
1046 * @ops: standard thermal cooling devices callbacks.
1047 *
1048 * This interface function adds a new thermal cooling device (fan/processor/...)
1049 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1050 * to all the thermal zone devices registered at the same time.
1051 * It also gives the opportunity to link the cooling device to a device tree
1052 * node, so that it can be bound to a thermal zone created out of device tree.
1053 *
1054 * Return: a pointer to the created struct thermal_cooling_device or an
1055 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1056 */
1057static struct thermal_cooling_device *
1058__thermal_cooling_device_register(struct device_node *np,
1059 const char *type, void *devdata,
1060 const struct thermal_cooling_device_ops *ops)
1061{
1062 struct thermal_cooling_device *cdev;
1063 unsigned long current_state;
1064 int id, ret;
1065
1066 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1067 !ops->set_cur_state)
1068 return ERR_PTR(error: -EINVAL);
1069
1070 if (!thermal_class)
1071 return ERR_PTR(error: -ENODEV);
1072
1073 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1074 if (!cdev)
1075 return ERR_PTR(error: -ENOMEM);
1076
1077 ret = ida_alloc(ida: &thermal_cdev_ida, GFP_KERNEL);
1078 if (ret < 0)
1079 goto out_kfree_cdev;
1080 cdev->id = ret;
1081 id = ret;
1082
1083 cdev->type = kstrdup_const(s: type ? type : "", GFP_KERNEL);
1084 if (!cdev->type) {
1085 ret = -ENOMEM;
1086 goto out_ida_remove;
1087 }
1088
1089 mutex_init(&cdev->lock);
1090 INIT_LIST_HEAD(list: &cdev->thermal_instances);
1091 cdev->np = np;
1092 cdev->ops = ops;
1093 cdev->updated = false;
1094 cdev->device.class = thermal_class;
1095 cdev->devdata = devdata;
1096
1097 ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
1098 if (ret)
1099 goto out_cdev_type;
1100
1101 /*
1102 * The cooling device's current state is only needed for debug
1103 * initialization below, so a failure to get it does not cause
1104 * the entire cooling device initialization to fail. However,
1105 * the debug will not work for the device if its initial state
1106 * cannot be determined and drivers are responsible for ensuring
1107 * that this will not happen.
1108 */
1109 ret = cdev->ops->get_cur_state(cdev, &current_state);
1110 if (ret)
1111 current_state = ULONG_MAX;
1112
1113 thermal_cooling_device_setup_sysfs(cdev);
1114
1115 ret = dev_set_name(dev: &cdev->device, name: "cooling_device%d", cdev->id);
1116 if (ret)
1117 goto out_cooling_dev;
1118
1119 ret = device_register(dev: &cdev->device);
1120 if (ret) {
1121 /* thermal_release() handles rest of the cleanup */
1122 put_device(dev: &cdev->device);
1123 return ERR_PTR(error: ret);
1124 }
1125
1126 if (current_state <= cdev->max_state)
1127 thermal_debug_cdev_add(cdev, state: current_state);
1128
1129 thermal_cooling_device_init_complete(cdev);
1130
1131 return cdev;
1132
1133out_cooling_dev:
1134 thermal_cooling_device_destroy_sysfs(cdev);
1135out_cdev_type:
1136 kfree_const(x: cdev->type);
1137out_ida_remove:
1138 ida_free(&thermal_cdev_ida, id);
1139out_kfree_cdev:
1140 kfree(objp: cdev);
1141 return ERR_PTR(error: ret);
1142}
1143
1144/**
1145 * thermal_cooling_device_register() - register a new thermal cooling device
1146 * @type: the thermal cooling device type.
1147 * @devdata: device private data.
1148 * @ops: standard thermal cooling devices callbacks.
1149 *
1150 * This interface function adds a new thermal cooling device (fan/processor/...)
1151 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1152 * to all the thermal zone devices registered at the same time.
1153 *
1154 * Return: a pointer to the created struct thermal_cooling_device or an
1155 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1156 */
1157struct thermal_cooling_device *
1158thermal_cooling_device_register(const char *type, void *devdata,
1159 const struct thermal_cooling_device_ops *ops)
1160{
1161 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1162}
1163EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1164
1165/**
1166 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1167 * @np: a pointer to a device tree node.
1168 * @type: the thermal cooling device type.
1169 * @devdata: device private data.
1170 * @ops: standard thermal cooling devices callbacks.
1171 *
1172 * This function will register a cooling device with device tree node reference.
1173 * This interface function adds a new thermal cooling device (fan/processor/...)
1174 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1175 * to all the thermal zone devices registered at the same time.
1176 *
1177 * Return: a pointer to the created struct thermal_cooling_device or an
1178 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1179 */
1180struct thermal_cooling_device *
1181thermal_of_cooling_device_register(struct device_node *np,
1182 const char *type, void *devdata,
1183 const struct thermal_cooling_device_ops *ops)
1184{
1185 return __thermal_cooling_device_register(np, type, devdata, ops);
1186}
1187EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1188
1189static void thermal_cooling_device_release(struct device *dev, void *res)
1190{
1191 thermal_cooling_device_unregister(
1192 *(struct thermal_cooling_device **)res);
1193}
1194
1195/**
1196 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1197 * device
1198 * @dev: a valid struct device pointer of a sensor device.
1199 * @np: a pointer to a device tree node.
1200 * @type: the thermal cooling device type.
1201 * @devdata: device private data.
1202 * @ops: standard thermal cooling devices callbacks.
1203 *
1204 * This function will register a cooling device with device tree node reference.
1205 * This interface function adds a new thermal cooling device (fan/processor/...)
1206 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1207 * to all the thermal zone devices registered at the same time.
1208 *
1209 * Return: a pointer to the created struct thermal_cooling_device or an
1210 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1211 */
1212struct thermal_cooling_device *
1213devm_thermal_of_cooling_device_register(struct device *dev,
1214 struct device_node *np,
1215 const char *type, void *devdata,
1216 const struct thermal_cooling_device_ops *ops)
1217{
1218 struct thermal_cooling_device **ptr, *tcd;
1219
1220 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1221 GFP_KERNEL);
1222 if (!ptr)
1223 return ERR_PTR(error: -ENOMEM);
1224
1225 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1226 if (IS_ERR(ptr: tcd)) {
1227 devres_free(res: ptr);
1228 return tcd;
1229 }
1230
1231 *ptr = tcd;
1232 devres_add(dev, res: ptr);
1233
1234 return tcd;
1235}
1236EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1237
1238static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1239{
1240 struct thermal_cooling_device *pos = NULL;
1241
1242 list_for_each_entry(pos, &thermal_cdev_list, node) {
1243 if (pos == cdev)
1244 return true;
1245 }
1246
1247 return false;
1248}
1249
1250/**
1251 * thermal_cooling_device_update - Update a cooling device object
1252 * @cdev: Target cooling device.
1253 *
1254 * Update @cdev to reflect a change of the underlying hardware or platform.
1255 *
1256 * Must be called when the maximum cooling state of @cdev becomes invalid and so
1257 * its .get_max_state() callback needs to be run to produce the new maximum
1258 * cooling state value.
1259 */
1260void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1261{
1262 struct thermal_instance *ti;
1263 unsigned long state;
1264
1265 if (IS_ERR_OR_NULL(ptr: cdev))
1266 return;
1267
1268 /*
1269 * Hold thermal_list_lock throughout the update to prevent the device
1270 * from going away while being updated.
1271 */
1272 guard(mutex)(T: &thermal_list_lock);
1273
1274 if (!thermal_cooling_device_present(cdev))
1275 return;
1276
1277 /*
1278 * Update under the cdev lock to prevent the state from being set beyond
1279 * the new limit concurrently.
1280 */
1281 guard(cooling_dev)(T: cdev);
1282
1283 if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1284 return;
1285
1286 thermal_cooling_device_stats_reinit(cdev);
1287
1288 list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1289 if (ti->upper == cdev->max_state)
1290 continue;
1291
1292 if (ti->upper < cdev->max_state) {
1293 if (ti->upper_no_limit)
1294 ti->upper = cdev->max_state;
1295
1296 continue;
1297 }
1298
1299 ti->upper = cdev->max_state;
1300 if (ti->lower > ti->upper)
1301 ti->lower = ti->upper;
1302
1303 if (ti->target == THERMAL_NO_TARGET)
1304 continue;
1305
1306 if (ti->target > ti->upper)
1307 ti->target = ti->upper;
1308 }
1309
1310 if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1311 return;
1312
1313 thermal_cooling_device_stats_update(cdev, new_state: state);
1314}
1315EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1316
1317static void __thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1318 struct thermal_cooling_device *cdev)
1319{
1320 struct thermal_trip_desc *td;
1321
1322 for_each_trip_desc(tz, td)
1323 thermal_unbind_cdev_from_trip(tz, td, cdev);
1324}
1325
1326static void thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1327 struct thermal_cooling_device *cdev)
1328{
1329 guard(thermal_zone)(T: tz);
1330
1331 __thermal_zone_cdev_unbind(tz, cdev);
1332}
1333
1334static bool thermal_cooling_device_exit(struct thermal_cooling_device *cdev)
1335{
1336 struct thermal_zone_device *tz;
1337
1338 guard(mutex)(T: &thermal_list_lock);
1339
1340 if (!thermal_cooling_device_present(cdev))
1341 return false;
1342
1343 list_del(entry: &cdev->node);
1344
1345 list_for_each_entry(tz, &thermal_tz_list, node)
1346 thermal_zone_cdev_unbind(tz, cdev);
1347
1348 return true;
1349}
1350
1351/**
1352 * thermal_cooling_device_unregister() - removes a thermal cooling device
1353 * @cdev: Thermal cooling device to remove.
1354 */
1355void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1356{
1357 if (!cdev)
1358 return;
1359
1360 thermal_debug_cdev_remove(cdev);
1361
1362 if (thermal_cooling_device_exit(cdev))
1363 device_unregister(dev: &cdev->device);
1364}
1365EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1366
1367int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1368{
1369 const struct thermal_trip_desc *td;
1370 int ret = -EINVAL;
1371
1372 if (tz->ops.get_crit_temp)
1373 return tz->ops.get_crit_temp(tz, temp);
1374
1375 guard(thermal_zone)(T: tz);
1376
1377 for_each_trip_desc(tz, td) {
1378 const struct thermal_trip *trip = &td->trip;
1379
1380 if (trip->type == THERMAL_TRIP_CRITICAL) {
1381 *temp = trip->temperature;
1382 ret = 0;
1383 break;
1384 }
1385 }
1386
1387 return ret;
1388}
1389EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1390
1391static void thermal_zone_device_check(struct work_struct *work)
1392{
1393 struct thermal_zone_device *tz = container_of(work, struct
1394 thermal_zone_device,
1395 poll_queue.work);
1396 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1397}
1398
1399static void thermal_zone_device_init(struct thermal_zone_device *tz)
1400{
1401 struct thermal_trip_desc *td, *next;
1402
1403 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1404
1405 tz->temperature = THERMAL_TEMP_INIT;
1406 tz->passive = 0;
1407 tz->prev_low_trip = -INT_MAX;
1408 tz->prev_high_trip = INT_MAX;
1409 for_each_trip_desc(tz, td) {
1410 struct thermal_instance *instance;
1411
1412 list_for_each_entry(instance, &td->thermal_instances, trip_node)
1413 instance->initialized = false;
1414 }
1415 /*
1416 * At this point, all valid trips need to be moved to trips_high so that
1417 * mitigation can be started if the zone temperature is above them.
1418 */
1419 list_for_each_entry_safe(td, next, &tz->trips_invalid, list_node) {
1420 if (td->trip.temperature != THERMAL_TEMP_INVALID)
1421 move_to_trips_high(tz, td);
1422 }
1423 /* The trips_reached list may not be empty during system resume. */
1424 list_for_each_entry_safe(td, next, &tz->trips_reached, list_node) {
1425 if (td->trip.temperature == THERMAL_TEMP_INVALID)
1426 move_to_trips_invalid(tz, td);
1427 else
1428 move_to_trips_high(tz, td);
1429 }
1430}
1431
1432static int thermal_zone_init_governor(struct thermal_zone_device *tz)
1433{
1434 struct thermal_governor *governor;
1435
1436 guard(mutex)(T: &thermal_governor_lock);
1437
1438 if (tz->tzp)
1439 governor = __find_governor(name: tz->tzp->governor_name);
1440 else
1441 governor = def_governor;
1442
1443 return thermal_set_governor(tz, new_gov: governor);
1444}
1445
1446static void thermal_zone_init_complete(struct thermal_zone_device *tz)
1447{
1448 struct thermal_cooling_device *cdev;
1449
1450 guard(mutex)(T: &thermal_list_lock);
1451
1452 list_add_tail(new: &tz->node, head: &thermal_tz_list);
1453
1454 guard(thermal_zone)(T: tz);
1455
1456 /* Bind cooling devices for this zone. */
1457 list_for_each_entry(cdev, &thermal_cdev_list, node)
1458 __thermal_zone_cdev_bind(tz, cdev);
1459
1460 tz->state &= ~TZ_STATE_FLAG_INIT;
1461 /*
1462 * If system suspend or resume is in progress at this point, the
1463 * new thermal zone needs to be marked as suspended because
1464 * thermal_pm_notify() has run already.
1465 */
1466 if (thermal_pm_suspended)
1467 tz->state |= TZ_STATE_FLAG_SUSPENDED;
1468
1469 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
1470}
1471
1472/**
1473 * thermal_zone_device_register_with_trips() - register a new thermal zone device
1474 * @type: the thermal zone device type
1475 * @trips: a pointer to an array of thermal trips
1476 * @num_trips: the number of trip points the thermal zone support
1477 * @devdata: private device data
1478 * @ops: standard thermal zone device callbacks
1479 * @tzp: thermal zone platform parameters
1480 * @passive_delay: number of milliseconds to wait between polls when
1481 * performing passive cooling
1482 * @polling_delay: number of milliseconds to wait between polls when checking
1483 * whether trip points have been crossed (0 for interrupt
1484 * driven systems)
1485 *
1486 * This interface function adds a new thermal zone device (sensor) to
1487 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1488 * thermal cooling devices registered at the same time.
1489 * thermal_zone_device_unregister() must be called when the device is no
1490 * longer needed. The passive cooling depends on the .get_trend() return value.
1491 *
1492 * Return: a pointer to the created struct thermal_zone_device or an
1493 * in case of error, an ERR_PTR. Caller must check return value with
1494 * IS_ERR*() helpers.
1495 */
1496struct thermal_zone_device *
1497thermal_zone_device_register_with_trips(const char *type,
1498 const struct thermal_trip *trips,
1499 int num_trips, void *devdata,
1500 const struct thermal_zone_device_ops *ops,
1501 const struct thermal_zone_params *tzp,
1502 unsigned int passive_delay,
1503 unsigned int polling_delay)
1504{
1505 const struct thermal_trip *trip = trips;
1506 struct thermal_zone_device *tz;
1507 struct thermal_trip_desc *td;
1508 int id;
1509 int result;
1510
1511 if (!type || strlen(type) == 0) {
1512 pr_err("No thermal zone type defined\n");
1513 return ERR_PTR(error: -EINVAL);
1514 }
1515
1516 if (strlen(type) >= THERMAL_NAME_LENGTH) {
1517 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1518 type, THERMAL_NAME_LENGTH);
1519 return ERR_PTR(error: -EINVAL);
1520 }
1521
1522 if (num_trips < 0) {
1523 pr_err("Incorrect number of thermal trips\n");
1524 return ERR_PTR(error: -EINVAL);
1525 }
1526
1527 if (!ops || !ops->get_temp) {
1528 pr_err("Thermal zone device ops not defined or invalid\n");
1529 return ERR_PTR(error: -EINVAL);
1530 }
1531
1532 if (num_trips > 0 && !trips)
1533 return ERR_PTR(error: -EINVAL);
1534
1535 if (polling_delay && passive_delay > polling_delay)
1536 return ERR_PTR(error: -EINVAL);
1537
1538 if (!thermal_class)
1539 return ERR_PTR(error: -ENODEV);
1540
1541 tz = kzalloc(struct_size(tz, trips, num_trips), GFP_KERNEL);
1542 if (!tz)
1543 return ERR_PTR(error: -ENOMEM);
1544
1545 if (tzp) {
1546 tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1547 if (!tz->tzp) {
1548 result = -ENOMEM;
1549 goto free_tz;
1550 }
1551 }
1552
1553 INIT_LIST_HEAD(list: &tz->node);
1554 INIT_LIST_HEAD(list: &tz->trips_high);
1555 INIT_LIST_HEAD(list: &tz->trips_reached);
1556 INIT_LIST_HEAD(list: &tz->trips_invalid);
1557 ida_init(ida: &tz->ida);
1558 mutex_init(&tz->lock);
1559 init_completion(x: &tz->removal);
1560 init_completion(x: &tz->resume);
1561 id = ida_alloc(ida: &thermal_tz_ida, GFP_KERNEL);
1562 if (id < 0) {
1563 result = id;
1564 goto free_tzp;
1565 }
1566
1567 tz->id = id;
1568 strscpy(tz->type, type, sizeof(tz->type));
1569
1570 tz->ops = *ops;
1571 if (!tz->ops.critical)
1572 tz->ops.critical = thermal_zone_device_critical;
1573
1574 tz->device.class = thermal_class;
1575 tz->devdata = devdata;
1576 tz->num_trips = num_trips;
1577 for_each_trip_desc(tz, td) {
1578 td->trip = *trip++;
1579 INIT_LIST_HEAD(list: &td->thermal_instances);
1580 INIT_LIST_HEAD(list: &td->list_node);
1581 /*
1582 * Mark all thresholds as invalid to start with even though
1583 * this only matters for the trips that start as invalid and
1584 * become valid later.
1585 */
1586 move_to_trips_invalid(tz, td);
1587 }
1588
1589 tz->polling_delay_jiffies = msecs_to_jiffies(m: polling_delay);
1590 tz->passive_delay_jiffies = msecs_to_jiffies(m: passive_delay);
1591 tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
1592
1593 tz->state = TZ_STATE_FLAG_INIT;
1594
1595 result = dev_set_name(dev: &tz->device, name: "thermal_zone%d", tz->id);
1596 if (result)
1597 goto remove_id;
1598
1599 thermal_zone_device_init(tz);
1600
1601 result = thermal_zone_init_governor(tz);
1602 if (result)
1603 goto remove_id;
1604
1605 /* sys I/F */
1606 /* Add nodes that are always present via .groups */
1607 result = thermal_zone_create_device_groups(tz);
1608 if (result)
1609 goto remove_id;
1610
1611 result = device_register(dev: &tz->device);
1612 if (result)
1613 goto release_device;
1614
1615 if (!tz->tzp || !tz->tzp->no_hwmon) {
1616 result = thermal_add_hwmon_sysfs(tz);
1617 if (result)
1618 goto unregister;
1619 }
1620
1621 result = thermal_thresholds_init(tz);
1622 if (result)
1623 goto remove_hwmon;
1624
1625 thermal_zone_init_complete(tz);
1626
1627 thermal_notify_tz_create(tz);
1628
1629 thermal_debug_tz_add(tz);
1630
1631 return tz;
1632
1633remove_hwmon:
1634 thermal_remove_hwmon_sysfs(tz);
1635unregister:
1636 device_del(dev: &tz->device);
1637release_device:
1638 put_device(dev: &tz->device);
1639remove_id:
1640 ida_free(&thermal_tz_ida, id);
1641free_tzp:
1642 kfree(objp: tz->tzp);
1643free_tz:
1644 kfree(objp: tz);
1645 return ERR_PTR(error: result);
1646}
1647EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1648
1649struct thermal_zone_device *thermal_tripless_zone_device_register(
1650 const char *type,
1651 void *devdata,
1652 const struct thermal_zone_device_ops *ops,
1653 const struct thermal_zone_params *tzp)
1654{
1655 return thermal_zone_device_register_with_trips(type, NULL, 0, devdata,
1656 ops, tzp, 0, 0);
1657}
1658EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1659
1660void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1661{
1662 return tzd->devdata;
1663}
1664EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1665
1666const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1667{
1668 return tzd->type;
1669}
1670EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1671
1672int thermal_zone_device_id(struct thermal_zone_device *tzd)
1673{
1674 return tzd->id;
1675}
1676EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1677
1678struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1679{
1680 return &tzd->device;
1681}
1682EXPORT_SYMBOL_GPL(thermal_zone_device);
1683
1684static bool thermal_zone_exit(struct thermal_zone_device *tz)
1685{
1686 struct thermal_cooling_device *cdev;
1687
1688 guard(mutex)(T: &thermal_list_lock);
1689
1690 if (list_empty(head: &tz->node))
1691 return false;
1692
1693 guard(thermal_zone)(T: tz);
1694
1695 tz->state |= TZ_STATE_FLAG_EXIT;
1696 list_del_init(entry: &tz->node);
1697
1698 /* Unbind all cdevs associated with this thermal zone. */
1699 list_for_each_entry(cdev, &thermal_cdev_list, node)
1700 __thermal_zone_cdev_unbind(tz, cdev);
1701
1702 return true;
1703}
1704
1705/**
1706 * thermal_zone_device_unregister - removes the registered thermal zone device
1707 * @tz: the thermal zone device to remove
1708 */
1709void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1710{
1711 if (!tz)
1712 return;
1713
1714 thermal_debug_tz_remove(tz);
1715
1716 if (!thermal_zone_exit(tz))
1717 return;
1718
1719 cancel_delayed_work_sync(dwork: &tz->poll_queue);
1720
1721 thermal_set_governor(tz, NULL);
1722
1723 thermal_thresholds_exit(tz);
1724 thermal_remove_hwmon_sysfs(tz);
1725 ida_free(&thermal_tz_ida, id: tz->id);
1726 ida_destroy(ida: &tz->ida);
1727
1728 device_del(dev: &tz->device);
1729 put_device(dev: &tz->device);
1730
1731 thermal_notify_tz_delete(tz);
1732
1733 wait_for_completion(&tz->removal);
1734 kfree(objp: tz->tzp);
1735 kfree(objp: tz);
1736}
1737EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1738
1739/**
1740 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1741 * @name: thermal zone name to fetch the temperature
1742 *
1743 * When only one zone is found with the passed name, returns a reference to it.
1744 *
1745 * Return: On success returns a reference to an unique thermal zone with
1746 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1747 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1748 */
1749struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1750{
1751 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(error: -EINVAL);
1752 unsigned int found = 0;
1753
1754 if (!name)
1755 return ERR_PTR(error: -EINVAL);
1756
1757 guard(mutex)(T: &thermal_list_lock);
1758
1759 list_for_each_entry(pos, &thermal_tz_list, node)
1760 if (!strncasecmp(s1: name, s2: pos->type, THERMAL_NAME_LENGTH)) {
1761 found++;
1762 ref = pos;
1763 }
1764
1765 if (!found)
1766 return ERR_PTR(error: -ENODEV);
1767
1768 /* Success only when one zone is found. */
1769 if (found > 1)
1770 return ERR_PTR(error: -EEXIST);
1771
1772 return ref;
1773}
1774EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1775
1776static void thermal_zone_device_resume(struct work_struct *work)
1777{
1778 struct thermal_zone_device *tz;
1779
1780 tz = container_of(work, struct thermal_zone_device, poll_queue.work);
1781
1782 guard(thermal_zone)(T: tz);
1783
1784 tz->state &= ~(TZ_STATE_FLAG_SUSPENDED | TZ_STATE_FLAG_RESUMING);
1785
1786 thermal_debug_tz_resume(tz);
1787 thermal_zone_device_init(tz);
1788 thermal_governor_update_tz(tz, reason: THERMAL_TZ_RESUME);
1789 __thermal_zone_device_update(tz, event: THERMAL_TZ_RESUME);
1790
1791 complete(&tz->resume);
1792}
1793
1794static void thermal_zone_pm_prepare(struct thermal_zone_device *tz)
1795{
1796 guard(thermal_zone)(T: tz);
1797
1798 if (tz->state & TZ_STATE_FLAG_RESUMING) {
1799 /*
1800 * thermal_zone_device_resume() queued up for this zone has not
1801 * acquired the lock yet, so release it to let the function run
1802 * and wait util it has done the work.
1803 */
1804 scoped_guard(thermal_zone_reverse, tz) {
1805 wait_for_completion(&tz->resume);
1806 }
1807 }
1808
1809 tz->state |= TZ_STATE_FLAG_SUSPENDED;
1810}
1811
1812static void thermal_pm_notify_prepare(void)
1813{
1814 struct thermal_zone_device *tz;
1815
1816 guard(mutex)(T: &thermal_list_lock);
1817
1818 thermal_pm_suspended = true;
1819
1820 list_for_each_entry(tz, &thermal_tz_list, node)
1821 thermal_zone_pm_prepare(tz);
1822}
1823
1824static void thermal_zone_pm_complete(struct thermal_zone_device *tz)
1825{
1826 guard(thermal_zone)(T: tz);
1827
1828 cancel_delayed_work(dwork: &tz->poll_queue);
1829
1830 reinit_completion(x: &tz->resume);
1831 tz->state |= TZ_STATE_FLAG_RESUMING;
1832
1833 /*
1834 * Replace the work function with the resume one, which will restore the
1835 * original work function and schedule the polling work if needed.
1836 */
1837 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_resume);
1838 /* Queue up the work without a delay. */
1839 mod_delayed_work(wq: system_freezable_power_efficient_wq, dwork: &tz->poll_queue, delay: 0);
1840}
1841
1842static void thermal_pm_notify_complete(void)
1843{
1844 struct thermal_zone_device *tz;
1845
1846 guard(mutex)(T: &thermal_list_lock);
1847
1848 thermal_pm_suspended = false;
1849
1850 list_for_each_entry(tz, &thermal_tz_list, node)
1851 thermal_zone_pm_complete(tz);
1852}
1853
1854static int thermal_pm_notify(struct notifier_block *nb,
1855 unsigned long mode, void *_unused)
1856{
1857 switch (mode) {
1858 case PM_HIBERNATION_PREPARE:
1859 case PM_RESTORE_PREPARE:
1860 case PM_SUSPEND_PREPARE:
1861 thermal_pm_notify_prepare();
1862 break;
1863 case PM_POST_HIBERNATION:
1864 case PM_POST_RESTORE:
1865 case PM_POST_SUSPEND:
1866 thermal_pm_notify_complete();
1867 break;
1868 default:
1869 break;
1870 }
1871 return 0;
1872}
1873
1874static struct notifier_block thermal_pm_nb = {
1875 .notifier_call = thermal_pm_notify,
1876 /*
1877 * Run at the lowest priority to avoid interference between the thermal
1878 * zone resume work items spawned by thermal_pm_notify() and the other
1879 * PM notifiers.
1880 */
1881 .priority = INT_MIN,
1882};
1883
1884static int __init thermal_init(void)
1885{
1886 int result;
1887
1888 thermal_debug_init();
1889
1890 result = thermal_netlink_init();
1891 if (result)
1892 goto error;
1893
1894 result = thermal_register_governors();
1895 if (result)
1896 goto unregister_netlink;
1897
1898 thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1899 if (!thermal_class) {
1900 result = -ENOMEM;
1901 goto unregister_governors;
1902 }
1903
1904 thermal_class->name = "thermal";
1905 thermal_class->dev_release = thermal_release;
1906
1907 result = class_register(class: thermal_class);
1908 if (result) {
1909 kfree(objp: thermal_class);
1910 thermal_class = NULL;
1911 goto unregister_governors;
1912 }
1913
1914 result = register_pm_notifier(nb: &thermal_pm_nb);
1915 if (result)
1916 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1917 result);
1918
1919 return 0;
1920
1921unregister_governors:
1922 thermal_unregister_governors();
1923unregister_netlink:
1924 thermal_netlink_exit();
1925error:
1926 mutex_destroy(lock: &thermal_list_lock);
1927 mutex_destroy(lock: &thermal_governor_lock);
1928 return result;
1929}
1930postcore_initcall(thermal_init);
1931