1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * thermal.c - Generic Thermal Management Sysfs support.
4 *
5 * Copyright (C) 2008 Intel Corp
6 * Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
7 * Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
8 */
9
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/slab.h>
16 #include <linux/kdev_t.h>
17 #include <linux/idr.h>
18 #include <linux/thermal.h>
19 #include <linux/reboot.h>
20 #include <linux/string.h>
21 #include <linux/of.h>
22 #include <linux/suspend.h>
23
24 #define CREATE_TRACE_POINTS
25 #include <trace/events/thermal.h>
26
27 #include "thermal_core.h"
28 #include "thermal_hwmon.h"
29
30 static DEFINE_IDA(thermal_tz_ida);
31 static DEFINE_IDA(thermal_cdev_ida);
32
33 static LIST_HEAD(thermal_tz_list);
34 static LIST_HEAD(thermal_cdev_list);
35 static LIST_HEAD(thermal_governor_list);
36
37 static DEFINE_MUTEX(thermal_list_lock);
38 static DEFINE_MUTEX(thermal_governor_lock);
39 static DEFINE_MUTEX(poweroff_lock);
40
41 static atomic_t in_suspend;
42 static bool power_off_triggered;
43
44 static struct thermal_governor *def_governor;
45
46 /*
47 * Governor section: set of functions to handle thermal governors
48 *
49 * Functions to help in the life cycle of thermal governors within
50 * the thermal core and by the thermal governor code.
51 */
52
__find_governor(const char * name)53 static struct thermal_governor *__find_governor(const char *name)
54 {
55 struct thermal_governor *pos;
56
57 if (!name || !name[0])
58 return def_governor;
59
60 list_for_each_entry(pos, &thermal_governor_list, governor_list)
61 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
62 return pos;
63
64 return NULL;
65 }
66
67 /**
68 * bind_previous_governor() - bind the previous governor of the thermal zone
69 * @tz: a valid pointer to a struct thermal_zone_device
70 * @failed_gov_name: the name of the governor that failed to register
71 *
72 * Register the previous governor of the thermal zone after a new
73 * governor has failed to be bound.
74 */
bind_previous_governor(struct thermal_zone_device * tz,const char * failed_gov_name)75 static void bind_previous_governor(struct thermal_zone_device *tz,
76 const char *failed_gov_name)
77 {
78 if (tz->governor && tz->governor->bind_to_tz) {
79 if (tz->governor->bind_to_tz(tz)) {
80 dev_err(&tz->device,
81 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
82 failed_gov_name, tz->governor->name, tz->type);
83 tz->governor = NULL;
84 }
85 }
86 }
87
88 /**
89 * thermal_set_governor() - Switch to another governor
90 * @tz: a valid pointer to a struct thermal_zone_device
91 * @new_gov: pointer to the new governor
92 *
93 * Change the governor of thermal zone @tz.
94 *
95 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
96 */
thermal_set_governor(struct thermal_zone_device * tz,struct thermal_governor * new_gov)97 static int thermal_set_governor(struct thermal_zone_device *tz,
98 struct thermal_governor *new_gov)
99 {
100 int ret = 0;
101
102 if (tz->governor && tz->governor->unbind_from_tz)
103 tz->governor->unbind_from_tz(tz);
104
105 if (new_gov && new_gov->bind_to_tz) {
106 ret = new_gov->bind_to_tz(tz);
107 if (ret) {
108 bind_previous_governor(tz, new_gov->name);
109
110 return ret;
111 }
112 }
113
114 tz->governor = new_gov;
115
116 return ret;
117 }
118
thermal_register_governor(struct thermal_governor * governor)119 int thermal_register_governor(struct thermal_governor *governor)
120 {
121 int err;
122 const char *name;
123 struct thermal_zone_device *pos;
124
125 if (!governor)
126 return -EINVAL;
127
128 mutex_lock(&thermal_governor_lock);
129
130 err = -EBUSY;
131 if (!__find_governor(governor->name)) {
132 bool match_default;
133
134 err = 0;
135 list_add(&governor->governor_list, &thermal_governor_list);
136 match_default = !strncmp(governor->name,
137 DEFAULT_THERMAL_GOVERNOR,
138 THERMAL_NAME_LENGTH);
139
140 if (!def_governor && match_default)
141 def_governor = governor;
142 }
143
144 mutex_lock(&thermal_list_lock);
145
146 list_for_each_entry(pos, &thermal_tz_list, node) {
147 /*
148 * only thermal zones with specified tz->tzp->governor_name
149 * may run with tz->govenor unset
150 */
151 if (pos->governor)
152 continue;
153
154 name = pos->tzp->governor_name;
155
156 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
157 int ret;
158
159 ret = thermal_set_governor(pos, governor);
160 if (ret)
161 dev_err(&pos->device,
162 "Failed to set governor %s for thermal zone %s: %d\n",
163 governor->name, pos->type, ret);
164 }
165 }
166
167 mutex_unlock(&thermal_list_lock);
168 mutex_unlock(&thermal_governor_lock);
169
170 return err;
171 }
172
thermal_unregister_governor(struct thermal_governor * governor)173 void thermal_unregister_governor(struct thermal_governor *governor)
174 {
175 struct thermal_zone_device *pos;
176
177 if (!governor)
178 return;
179
180 mutex_lock(&thermal_governor_lock);
181
182 if (!__find_governor(governor->name))
183 goto exit;
184
185 mutex_lock(&thermal_list_lock);
186
187 list_for_each_entry(pos, &thermal_tz_list, node) {
188 if (!strncasecmp(pos->governor->name, governor->name,
189 THERMAL_NAME_LENGTH))
190 thermal_set_governor(pos, NULL);
191 }
192
193 mutex_unlock(&thermal_list_lock);
194 list_del(&governor->governor_list);
195 exit:
196 mutex_unlock(&thermal_governor_lock);
197 }
198
thermal_zone_device_set_policy(struct thermal_zone_device * tz,char * policy)199 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
200 char *policy)
201 {
202 struct thermal_governor *gov;
203 int ret = -EINVAL;
204
205 mutex_lock(&thermal_governor_lock);
206 mutex_lock(&tz->lock);
207
208 gov = __find_governor(strim(policy));
209 if (!gov)
210 goto exit;
211
212 ret = thermal_set_governor(tz, gov);
213
214 exit:
215 mutex_unlock(&tz->lock);
216 mutex_unlock(&thermal_governor_lock);
217
218 thermal_notify_tz_gov_change(tz->id, policy);
219
220 return ret;
221 }
222
thermal_build_list_of_policies(char * buf)223 int thermal_build_list_of_policies(char *buf)
224 {
225 struct thermal_governor *pos;
226 ssize_t count = 0;
227
228 mutex_lock(&thermal_governor_lock);
229
230 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
231 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
232 pos->name);
233 }
234 count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
235
236 mutex_unlock(&thermal_governor_lock);
237
238 return count;
239 }
240
thermal_unregister_governors(void)241 static void __init thermal_unregister_governors(void)
242 {
243 struct thermal_governor **governor;
244
245 for_each_governor_table(governor)
246 thermal_unregister_governor(*governor);
247 }
248
thermal_register_governors(void)249 static int __init thermal_register_governors(void)
250 {
251 int ret = 0;
252 struct thermal_governor **governor;
253
254 for_each_governor_table(governor) {
255 ret = thermal_register_governor(*governor);
256 if (ret) {
257 pr_err("Failed to register governor: '%s'",
258 (*governor)->name);
259 break;
260 }
261
262 pr_info("Registered thermal governor '%s'",
263 (*governor)->name);
264 }
265
266 if (ret) {
267 struct thermal_governor **gov;
268
269 for_each_governor_table(gov) {
270 if (gov == governor)
271 break;
272 thermal_unregister_governor(*gov);
273 }
274 }
275
276 return ret;
277 }
278
279 /*
280 * Zone update section: main control loop applied to each zone while monitoring
281 *
282 * in polling mode. The monitoring is done using a workqueue.
283 * Same update may be done on a zone by calling thermal_zone_device_update().
284 *
285 * An update means:
286 * - Non-critical trips will invoke the governor responsible for that zone;
287 * - Hot trips will produce a notification to userspace;
288 * - Critical trip point will cause a system shutdown.
289 */
thermal_zone_device_set_polling(struct thermal_zone_device * tz,int delay)290 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
291 int delay)
292 {
293 if (delay > 1000)
294 mod_delayed_work(system_freezable_power_efficient_wq,
295 &tz->poll_queue,
296 round_jiffies(msecs_to_jiffies(delay)));
297 else if (delay)
298 mod_delayed_work(system_freezable_power_efficient_wq,
299 &tz->poll_queue,
300 msecs_to_jiffies(delay));
301 else
302 cancel_delayed_work(&tz->poll_queue);
303 }
304
should_stop_polling(struct thermal_zone_device * tz)305 static inline bool should_stop_polling(struct thermal_zone_device *tz)
306 {
307 return !thermal_zone_device_is_enabled(tz);
308 }
309
monitor_thermal_zone(struct thermal_zone_device * tz)310 static void monitor_thermal_zone(struct thermal_zone_device *tz)
311 {
312 bool stop;
313
314 stop = should_stop_polling(tz);
315
316 mutex_lock(&tz->lock);
317
318 if (!stop && tz->passive)
319 thermal_zone_device_set_polling(tz, tz->passive_delay);
320 else if (!stop && tz->polling_delay)
321 thermal_zone_device_set_polling(tz, tz->polling_delay);
322 else
323 thermal_zone_device_set_polling(tz, 0);
324
325 mutex_unlock(&tz->lock);
326 }
327
handle_non_critical_trips(struct thermal_zone_device * tz,int trip)328 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
329 {
330 tz->governor ? tz->governor->throttle(tz, trip) :
331 def_governor->throttle(tz, trip);
332 }
333
334 /**
335 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
336 * @work: work_struct associated with the emergency poweroff function
337 *
338 * This function is called in very critical situations to force
339 * a kernel poweroff after a configurable timeout value.
340 */
thermal_emergency_poweroff_func(struct work_struct * work)341 static void thermal_emergency_poweroff_func(struct work_struct *work)
342 {
343 /*
344 * We have reached here after the emergency thermal shutdown
345 * Waiting period has expired. This means orderly_poweroff has
346 * not been able to shut off the system for some reason.
347 * Try to shut down the system immediately using kernel_power_off
348 * if populated
349 */
350 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
351 kernel_power_off();
352
353 /*
354 * Worst of the worst case trigger emergency restart
355 */
356 WARN(1, "Attempting emergency_restart: Temperature too high\n");
357 emergency_restart();
358 }
359
360 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
361 thermal_emergency_poweroff_func);
362
363 /**
364 * thermal_emergency_poweroff - Trigger an emergency system poweroff
365 *
366 * This may be called from any critical situation to trigger a system shutdown
367 * after a known period of time. By default this is not scheduled.
368 */
thermal_emergency_poweroff(void)369 static void thermal_emergency_poweroff(void)
370 {
371 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
372 /*
373 * poweroff_delay_ms must be a carefully profiled positive value.
374 * Its a must for thermal_emergency_poweroff_work to be scheduled
375 */
376 if (poweroff_delay_ms <= 0)
377 return;
378 schedule_delayed_work(&thermal_emergency_poweroff_work,
379 msecs_to_jiffies(poweroff_delay_ms));
380 }
381
handle_critical_trips(struct thermal_zone_device * tz,int trip,enum thermal_trip_type trip_type)382 static void handle_critical_trips(struct thermal_zone_device *tz,
383 int trip, enum thermal_trip_type trip_type)
384 {
385 int trip_temp;
386
387 tz->ops->get_trip_temp(tz, trip, &trip_temp);
388
389 /* If we have not crossed the trip_temp, we do not care. */
390 if (trip_temp <= 0 || tz->temperature < trip_temp)
391 return;
392
393 trace_thermal_zone_trip(tz, trip, trip_type);
394
395 if (tz->ops->notify)
396 tz->ops->notify(tz, trip, trip_type);
397
398 if (trip_type == THERMAL_TRIP_CRITICAL) {
399 dev_emerg(&tz->device,
400 "critical temperature reached (%d C), shutting down\n",
401 tz->temperature / 1000);
402 mutex_lock(&poweroff_lock);
403 if (!power_off_triggered) {
404 /*
405 * Queue a backup emergency shutdown in the event of
406 * orderly_poweroff failure
407 */
408 thermal_emergency_poweroff();
409 orderly_poweroff(true);
410 power_off_triggered = true;
411 }
412 mutex_unlock(&poweroff_lock);
413 }
414 }
415
handle_thermal_trip(struct thermal_zone_device * tz,int trip)416 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
417 {
418 enum thermal_trip_type type;
419 int trip_temp, hyst = 0;
420
421 /* Ignore disabled trip points */
422 if (test_bit(trip, &tz->trips_disabled))
423 return;
424
425 tz->ops->get_trip_temp(tz, trip, &trip_temp);
426 tz->ops->get_trip_type(tz, trip, &type);
427 if (tz->ops->get_trip_hyst)
428 tz->ops->get_trip_hyst(tz, trip, &hyst);
429
430 if (tz->last_temperature != THERMAL_TEMP_INVALID) {
431 if (tz->last_temperature < trip_temp &&
432 tz->temperature >= trip_temp)
433 thermal_notify_tz_trip_up(tz->id, trip);
434 if (tz->last_temperature >= trip_temp &&
435 tz->temperature < (trip_temp - hyst))
436 thermal_notify_tz_trip_down(tz->id, trip);
437 }
438
439 if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
440 handle_critical_trips(tz, trip, type);
441 else
442 handle_non_critical_trips(tz, trip);
443 /*
444 * Alright, we handled this trip successfully.
445 * So, start monitoring again.
446 */
447 monitor_thermal_zone(tz);
448 }
449
update_temperature(struct thermal_zone_device * tz)450 static void update_temperature(struct thermal_zone_device *tz)
451 {
452 int temp, ret;
453
454 ret = thermal_zone_get_temp(tz, &temp);
455 if (ret) {
456 if (ret != -EAGAIN)
457 dev_warn(&tz->device,
458 "failed to read out thermal zone (%d)\n",
459 ret);
460 return;
461 }
462
463 mutex_lock(&tz->lock);
464 tz->last_temperature = tz->temperature;
465 tz->temperature = temp;
466 mutex_unlock(&tz->lock);
467
468 trace_thermal_temperature(tz);
469
470 thermal_genl_sampling_temp(tz->id, temp);
471 }
472
thermal_zone_device_init(struct thermal_zone_device * tz)473 static void thermal_zone_device_init(struct thermal_zone_device *tz)
474 {
475 struct thermal_instance *pos;
476 tz->temperature = THERMAL_TEMP_INVALID;
477 tz->prev_low_trip = -INT_MAX;
478 tz->prev_high_trip = INT_MAX;
479 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
480 pos->initialized = false;
481 }
482
thermal_zone_device_reset(struct thermal_zone_device * tz)483 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
484 {
485 tz->passive = 0;
486 thermal_zone_device_init(tz);
487 }
488
thermal_zone_device_set_mode(struct thermal_zone_device * tz,enum thermal_device_mode mode)489 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
490 enum thermal_device_mode mode)
491 {
492 int ret = 0;
493
494 mutex_lock(&tz->lock);
495
496 /* do nothing if mode isn't changing */
497 if (mode == tz->mode) {
498 mutex_unlock(&tz->lock);
499
500 return ret;
501 }
502
503 if (tz->ops->change_mode)
504 ret = tz->ops->change_mode(tz, mode);
505
506 if (!ret)
507 tz->mode = mode;
508
509 mutex_unlock(&tz->lock);
510
511 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
512
513 if (mode == THERMAL_DEVICE_ENABLED)
514 thermal_notify_tz_enable(tz->id);
515 else
516 thermal_notify_tz_disable(tz->id);
517
518 return ret;
519 }
520
thermal_zone_device_enable(struct thermal_zone_device * tz)521 int thermal_zone_device_enable(struct thermal_zone_device *tz)
522 {
523 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
524 }
525 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
526
thermal_zone_device_disable(struct thermal_zone_device * tz)527 int thermal_zone_device_disable(struct thermal_zone_device *tz)
528 {
529 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
530 }
531 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
532
thermal_zone_device_is_enabled(struct thermal_zone_device * tz)533 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
534 {
535 enum thermal_device_mode mode;
536
537 mutex_lock(&tz->lock);
538
539 mode = tz->mode;
540
541 mutex_unlock(&tz->lock);
542
543 return mode == THERMAL_DEVICE_ENABLED;
544 }
545
thermal_zone_device_update(struct thermal_zone_device * tz,enum thermal_notify_event event)546 void thermal_zone_device_update(struct thermal_zone_device *tz,
547 enum thermal_notify_event event)
548 {
549 int count;
550
551 if (should_stop_polling(tz))
552 return;
553
554 if (atomic_read(&in_suspend))
555 return;
556
557 if (!tz->ops->get_temp)
558 return;
559
560 update_temperature(tz);
561
562 thermal_zone_set_trips(tz);
563
564 tz->notify_event = event;
565
566 for (count = 0; count < tz->trips; count++)
567 handle_thermal_trip(tz, count);
568 }
569 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
570
571 /**
572 * thermal_notify_framework - Sensor drivers use this API to notify framework
573 * @tz: thermal zone device
574 * @trip: indicates which trip point has been crossed
575 *
576 * This function handles the trip events from sensor drivers. It starts
577 * throttling the cooling devices according to the policy configured.
578 * For CRITICAL and HOT trip points, this notifies the respective drivers,
579 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
580 * The throttling policy is based on the configured platform data; if no
581 * platform data is provided, this uses the step_wise throttling policy.
582 */
thermal_notify_framework(struct thermal_zone_device * tz,int trip)583 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
584 {
585 handle_thermal_trip(tz, trip);
586 }
587 EXPORT_SYMBOL_GPL(thermal_notify_framework);
588
thermal_zone_device_check(struct work_struct * work)589 static void thermal_zone_device_check(struct work_struct *work)
590 {
591 struct thermal_zone_device *tz = container_of(work, struct
592 thermal_zone_device,
593 poll_queue.work);
594 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
595 }
596
597 /*
598 * Power actor section: interface to power actors to estimate power
599 *
600 * Set of functions used to interact to cooling devices that know
601 * how to estimate their devices power consumption.
602 */
603
604 /**
605 * power_actor_get_max_power() - get the maximum power that a cdev can consume
606 * @cdev: pointer to &thermal_cooling_device
607 * @max_power: pointer in which to store the maximum power
608 *
609 * Calculate the maximum power consumption in milliwats that the
610 * cooling device can currently consume and store it in @max_power.
611 *
612 * Return: 0 on success, -EINVAL if @cdev doesn't support the
613 * power_actor API or -E* on other error.
614 */
power_actor_get_max_power(struct thermal_cooling_device * cdev,u32 * max_power)615 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
616 u32 *max_power)
617 {
618 if (!cdev_is_power_actor(cdev))
619 return -EINVAL;
620
621 return cdev->ops->state2power(cdev, 0, max_power);
622 }
623
624 /**
625 * power_actor_get_min_power() - get the mainimum power that a cdev can consume
626 * @cdev: pointer to &thermal_cooling_device
627 * @min_power: pointer in which to store the minimum power
628 *
629 * Calculate the minimum power consumption in milliwatts that the
630 * cooling device can currently consume and store it in @min_power.
631 *
632 * Return: 0 on success, -EINVAL if @cdev doesn't support the
633 * power_actor API or -E* on other error.
634 */
power_actor_get_min_power(struct thermal_cooling_device * cdev,u32 * min_power)635 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
636 u32 *min_power)
637 {
638 unsigned long max_state;
639 int ret;
640
641 if (!cdev_is_power_actor(cdev))
642 return -EINVAL;
643
644 ret = cdev->ops->get_max_state(cdev, &max_state);
645 if (ret)
646 return ret;
647
648 return cdev->ops->state2power(cdev, max_state, min_power);
649 }
650
651 /**
652 * power_actor_set_power() - limit the maximum power a cooling device consumes
653 * @cdev: pointer to &thermal_cooling_device
654 * @instance: thermal instance to update
655 * @power: the power in milliwatts
656 *
657 * Set the cooling device to consume at most @power milliwatts. The limit is
658 * expected to be a cap at the maximum power consumption.
659 *
660 * Return: 0 on success, -EINVAL if the cooling device does not
661 * implement the power actor API or -E* for other failures.
662 */
power_actor_set_power(struct thermal_cooling_device * cdev,struct thermal_instance * instance,u32 power)663 int power_actor_set_power(struct thermal_cooling_device *cdev,
664 struct thermal_instance *instance, u32 power)
665 {
666 unsigned long state;
667 int ret;
668
669 if (!cdev_is_power_actor(cdev))
670 return -EINVAL;
671
672 ret = cdev->ops->power2state(cdev, power, &state);
673 if (ret)
674 return ret;
675
676 instance->target = state;
677 mutex_lock(&cdev->lock);
678 cdev->updated = false;
679 mutex_unlock(&cdev->lock);
680 thermal_cdev_update(cdev);
681
682 return 0;
683 }
684
thermal_zone_device_rebind_exception(struct thermal_zone_device * tz,const char * cdev_type,size_t size)685 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
686 const char *cdev_type, size_t size)
687 {
688 struct thermal_cooling_device *cdev = NULL;
689
690 mutex_lock(&thermal_list_lock);
691 list_for_each_entry(cdev, &thermal_cdev_list, node) {
692 /* skip non matching cdevs */
693 if (strncmp(cdev_type, cdev->type, size))
694 continue;
695
696 /* re binding the exception matching the type pattern */
697 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
698 THERMAL_NO_LIMIT,
699 THERMAL_NO_LIMIT,
700 THERMAL_WEIGHT_DEFAULT);
701 }
702 mutex_unlock(&thermal_list_lock);
703 }
704
for_each_thermal_governor(int (* cb)(struct thermal_governor *,void *),void * data)705 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
706 void *data)
707 {
708 struct thermal_governor *gov;
709 int ret = 0;
710
711 mutex_lock(&thermal_governor_lock);
712 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
713 ret = cb(gov, data);
714 if (ret)
715 break;
716 }
717 mutex_unlock(&thermal_governor_lock);
718
719 return ret;
720 }
721
for_each_thermal_cooling_device(int (* cb)(struct thermal_cooling_device *,void *),void * data)722 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
723 void *), void *data)
724 {
725 struct thermal_cooling_device *cdev;
726 int ret = 0;
727
728 mutex_lock(&thermal_list_lock);
729 list_for_each_entry(cdev, &thermal_cdev_list, node) {
730 ret = cb(cdev, data);
731 if (ret)
732 break;
733 }
734 mutex_unlock(&thermal_list_lock);
735
736 return ret;
737 }
738
for_each_thermal_zone(int (* cb)(struct thermal_zone_device *,void *),void * data)739 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
740 void *data)
741 {
742 struct thermal_zone_device *tz;
743 int ret = 0;
744
745 mutex_lock(&thermal_list_lock);
746 list_for_each_entry(tz, &thermal_tz_list, node) {
747 ret = cb(tz, data);
748 if (ret)
749 break;
750 }
751 mutex_unlock(&thermal_list_lock);
752
753 return ret;
754 }
755
thermal_zone_get_by_id(int id)756 struct thermal_zone_device *thermal_zone_get_by_id(int id)
757 {
758 struct thermal_zone_device *tz, *match = NULL;
759
760 mutex_lock(&thermal_list_lock);
761 list_for_each_entry(tz, &thermal_tz_list, node) {
762 if (tz->id == id) {
763 match = tz;
764 break;
765 }
766 }
767 mutex_unlock(&thermal_list_lock);
768
769 return match;
770 }
771
thermal_zone_device_unbind_exception(struct thermal_zone_device * tz,const char * cdev_type,size_t size)772 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
773 const char *cdev_type, size_t size)
774 {
775 struct thermal_cooling_device *cdev = NULL;
776
777 mutex_lock(&thermal_list_lock);
778 list_for_each_entry(cdev, &thermal_cdev_list, node) {
779 /* skip non matching cdevs */
780 if (strncmp(cdev_type, cdev->type, size))
781 continue;
782 /* unbinding the exception matching the type pattern */
783 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
784 cdev);
785 }
786 mutex_unlock(&thermal_list_lock);
787 }
788
789 /*
790 * Device management section: cooling devices, zones devices, and binding
791 *
792 * Set of functions provided by the thermal core for:
793 * - cooling devices lifecycle: registration, unregistration,
794 * binding, and unbinding.
795 * - thermal zone devices lifecycle: registration, unregistration,
796 * binding, and unbinding.
797 */
798
799 /**
800 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
801 * @tz: pointer to struct thermal_zone_device
802 * @trip: indicates which trip point the cooling devices is
803 * associated with in this thermal zone.
804 * @cdev: pointer to struct thermal_cooling_device
805 * @upper: the Maximum cooling state for this trip point.
806 * THERMAL_NO_LIMIT means no upper limit,
807 * and the cooling device can be in max_state.
808 * @lower: the Minimum cooling state can be used for this trip point.
809 * THERMAL_NO_LIMIT means no lower limit,
810 * and the cooling device can be in cooling state 0.
811 * @weight: The weight of the cooling device to be bound to the
812 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
813 * default value
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 */
thermal_zone_bind_cooling_device(struct thermal_zone_device * tz,int trip,struct thermal_cooling_device * cdev,unsigned long upper,unsigned long lower,unsigned int weight)821 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
822 int trip,
823 struct thermal_cooling_device *cdev,
824 unsigned long upper, unsigned long lower,
825 unsigned int weight)
826 {
827 struct thermal_instance *dev;
828 struct thermal_instance *pos;
829 struct thermal_zone_device *pos1;
830 struct thermal_cooling_device *pos2;
831 unsigned long max_state;
832 int result, ret;
833
834 if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
835 return -EINVAL;
836
837 list_for_each_entry(pos1, &thermal_tz_list, node) {
838 if (pos1 == tz)
839 break;
840 }
841 list_for_each_entry(pos2, &thermal_cdev_list, node) {
842 if (pos2 == cdev)
843 break;
844 }
845
846 if (tz != pos1 || cdev != pos2)
847 return -EINVAL;
848
849 ret = cdev->ops->get_max_state(cdev, &max_state);
850 if (ret)
851 return ret;
852
853 /* lower default 0, upper default max_state */
854 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
855 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
856
857 if (lower > upper || upper > max_state)
858 return -EINVAL;
859
860 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
861 if (!dev)
862 return -ENOMEM;
863 dev->tz = tz;
864 dev->cdev = cdev;
865 dev->trip = trip;
866 dev->upper = upper;
867 dev->lower = lower;
868 dev->target = THERMAL_NO_TARGET;
869 dev->weight = weight;
870
871 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
872 if (result < 0)
873 goto free_mem;
874
875 dev->id = result;
876 sprintf(dev->name, "cdev%d", dev->id);
877 result =
878 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
879 if (result)
880 goto release_ida;
881
882 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
883 sysfs_attr_init(&dev->attr.attr);
884 dev->attr.attr.name = dev->attr_name;
885 dev->attr.attr.mode = 0444;
886 dev->attr.show = trip_point_show;
887 result = device_create_file(&tz->device, &dev->attr);
888 if (result)
889 goto remove_symbol_link;
890
891 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
892 sysfs_attr_init(&dev->weight_attr.attr);
893 dev->weight_attr.attr.name = dev->weight_attr_name;
894 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
895 dev->weight_attr.show = weight_show;
896 dev->weight_attr.store = weight_store;
897 result = device_create_file(&tz->device, &dev->weight_attr);
898 if (result)
899 goto remove_trip_file;
900
901 mutex_lock(&tz->lock);
902 mutex_lock(&cdev->lock);
903 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
904 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
905 result = -EEXIST;
906 break;
907 }
908 if (!result) {
909 list_add_tail(&dev->tz_node, &tz->thermal_instances);
910 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
911 atomic_set(&tz->need_update, 1);
912 }
913 mutex_unlock(&cdev->lock);
914 mutex_unlock(&tz->lock);
915
916 if (!result)
917 return 0;
918
919 device_remove_file(&tz->device, &dev->weight_attr);
920 remove_trip_file:
921 device_remove_file(&tz->device, &dev->attr);
922 remove_symbol_link:
923 sysfs_remove_link(&tz->device.kobj, dev->name);
924 release_ida:
925 ida_simple_remove(&tz->ida, dev->id);
926 free_mem:
927 kfree(dev);
928 return result;
929 }
930 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
931
932 /**
933 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
934 * thermal zone.
935 * @tz: pointer to a struct thermal_zone_device.
936 * @trip: indicates which trip point the cooling devices is
937 * associated with in this thermal zone.
938 * @cdev: pointer to a struct thermal_cooling_device.
939 *
940 * This interface function unbind a thermal cooling device from the certain
941 * trip point of a thermal zone device.
942 * This function is usually called in the thermal zone device .unbind callback.
943 *
944 * Return: 0 on success, the proper error value otherwise.
945 */
thermal_zone_unbind_cooling_device(struct thermal_zone_device * tz,int trip,struct thermal_cooling_device * cdev)946 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
947 int trip,
948 struct thermal_cooling_device *cdev)
949 {
950 struct thermal_instance *pos, *next;
951
952 mutex_lock(&tz->lock);
953 mutex_lock(&cdev->lock);
954 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
955 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
956 list_del(&pos->tz_node);
957 list_del(&pos->cdev_node);
958 mutex_unlock(&cdev->lock);
959 mutex_unlock(&tz->lock);
960 goto unbind;
961 }
962 }
963 mutex_unlock(&cdev->lock);
964 mutex_unlock(&tz->lock);
965
966 return -ENODEV;
967
968 unbind:
969 device_remove_file(&tz->device, &pos->weight_attr);
970 device_remove_file(&tz->device, &pos->attr);
971 sysfs_remove_link(&tz->device.kobj, pos->name);
972 ida_simple_remove(&tz->ida, pos->id);
973 kfree(pos);
974 return 0;
975 }
976 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
977
thermal_release(struct device * dev)978 static void thermal_release(struct device *dev)
979 {
980 struct thermal_zone_device *tz;
981 struct thermal_cooling_device *cdev;
982
983 if (!strncmp(dev_name(dev), "thermal_zone",
984 sizeof("thermal_zone") - 1)) {
985 tz = to_thermal_zone(dev);
986 thermal_zone_destroy_device_groups(tz);
987 kfree(tz);
988 } else if (!strncmp(dev_name(dev), "cooling_device",
989 sizeof("cooling_device") - 1)) {
990 cdev = to_cooling_device(dev);
991 kfree(cdev);
992 }
993 }
994
995 static struct class thermal_class = {
996 .name = "thermal",
997 .dev_release = thermal_release,
998 };
999
1000 static inline
print_bind_err_msg(struct thermal_zone_device * tz,struct thermal_cooling_device * cdev,int ret)1001 void print_bind_err_msg(struct thermal_zone_device *tz,
1002 struct thermal_cooling_device *cdev, int ret)
1003 {
1004 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
1005 tz->type, cdev->type, ret);
1006 }
1007
__bind(struct thermal_zone_device * tz,int mask,struct thermal_cooling_device * cdev,unsigned long * limits,unsigned int weight)1008 static void __bind(struct thermal_zone_device *tz, int mask,
1009 struct thermal_cooling_device *cdev,
1010 unsigned long *limits,
1011 unsigned int weight)
1012 {
1013 int i, ret;
1014
1015 for (i = 0; i < tz->trips; i++) {
1016 if (mask & (1 << i)) {
1017 unsigned long upper, lower;
1018
1019 upper = THERMAL_NO_LIMIT;
1020 lower = THERMAL_NO_LIMIT;
1021 if (limits) {
1022 lower = limits[i * 2];
1023 upper = limits[i * 2 + 1];
1024 }
1025 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
1026 upper, lower,
1027 weight);
1028 if (ret)
1029 print_bind_err_msg(tz, cdev, ret);
1030 }
1031 }
1032 }
1033
bind_cdev(struct thermal_cooling_device * cdev)1034 static void bind_cdev(struct thermal_cooling_device *cdev)
1035 {
1036 int i, ret;
1037 const struct thermal_zone_params *tzp;
1038 struct thermal_zone_device *pos = NULL;
1039
1040 mutex_lock(&thermal_list_lock);
1041
1042 list_for_each_entry(pos, &thermal_tz_list, node) {
1043 if (!pos->tzp && !pos->ops->bind)
1044 continue;
1045
1046 if (pos->ops->bind) {
1047 ret = pos->ops->bind(pos, cdev);
1048 if (ret)
1049 print_bind_err_msg(pos, cdev, ret);
1050 continue;
1051 }
1052
1053 tzp = pos->tzp;
1054 if (!tzp || !tzp->tbp)
1055 continue;
1056
1057 for (i = 0; i < tzp->num_tbps; i++) {
1058 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1059 continue;
1060 if (tzp->tbp[i].match(pos, cdev))
1061 continue;
1062 tzp->tbp[i].cdev = cdev;
1063 __bind(pos, tzp->tbp[i].trip_mask, cdev,
1064 tzp->tbp[i].binding_limits,
1065 tzp->tbp[i].weight);
1066 }
1067 }
1068
1069 mutex_unlock(&thermal_list_lock);
1070 }
1071
1072 /**
1073 * __thermal_cooling_device_register() - register a new thermal cooling device
1074 * @np: a pointer to a device tree node.
1075 * @type: the thermal cooling device type.
1076 * @devdata: device private data.
1077 * @ops: standard thermal cooling devices callbacks.
1078 *
1079 * This interface function adds a new thermal cooling device (fan/processor/...)
1080 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1081 * to all the thermal zone devices registered at the same time.
1082 * It also gives the opportunity to link the cooling device to a device tree
1083 * node, so that it can be bound to a thermal zone created out of device tree.
1084 *
1085 * Return: a pointer to the created struct thermal_cooling_device or an
1086 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1087 */
1088 static struct thermal_cooling_device *
__thermal_cooling_device_register(struct device_node * np,const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1089 __thermal_cooling_device_register(struct device_node *np,
1090 const char *type, void *devdata,
1091 const struct thermal_cooling_device_ops *ops)
1092 {
1093 struct thermal_cooling_device *cdev;
1094 struct thermal_zone_device *pos = NULL;
1095 int result;
1096
1097 if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1098 return ERR_PTR(-EINVAL);
1099
1100 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1101 !ops->set_cur_state)
1102 return ERR_PTR(-EINVAL);
1103
1104 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1105 if (!cdev)
1106 return ERR_PTR(-ENOMEM);
1107
1108 result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1109 if (result < 0) {
1110 kfree(cdev);
1111 return ERR_PTR(result);
1112 }
1113
1114 cdev->id = result;
1115 strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1116 mutex_init(&cdev->lock);
1117 INIT_LIST_HEAD(&cdev->thermal_instances);
1118 cdev->np = np;
1119 cdev->ops = ops;
1120 cdev->updated = false;
1121 cdev->device.class = &thermal_class;
1122 cdev->devdata = devdata;
1123 thermal_cooling_device_setup_sysfs(cdev);
1124 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1125 result = device_register(&cdev->device);
1126 if (result) {
1127 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1128 put_device(&cdev->device);
1129 return ERR_PTR(result);
1130 }
1131
1132 /* Add 'this' new cdev to the global cdev list */
1133 mutex_lock(&thermal_list_lock);
1134 list_add(&cdev->node, &thermal_cdev_list);
1135 mutex_unlock(&thermal_list_lock);
1136
1137 /* Update binding information for 'this' new cdev */
1138 bind_cdev(cdev);
1139
1140 mutex_lock(&thermal_list_lock);
1141 list_for_each_entry(pos, &thermal_tz_list, node)
1142 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1143 thermal_zone_device_update(pos,
1144 THERMAL_EVENT_UNSPECIFIED);
1145 mutex_unlock(&thermal_list_lock);
1146
1147 return cdev;
1148 }
1149
1150 /**
1151 * thermal_cooling_device_register() - register a new thermal cooling device
1152 * @type: the thermal cooling device type.
1153 * @devdata: device private data.
1154 * @ops: standard thermal cooling devices callbacks.
1155 *
1156 * This interface function adds a new thermal cooling device (fan/processor/...)
1157 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1158 * to all the thermal zone devices registered at the same time.
1159 *
1160 * Return: a pointer to the created struct thermal_cooling_device or an
1161 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1162 */
1163 struct thermal_cooling_device *
thermal_cooling_device_register(const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1164 thermal_cooling_device_register(const char *type, void *devdata,
1165 const struct thermal_cooling_device_ops *ops)
1166 {
1167 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1168 }
1169 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1170
1171 /**
1172 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1173 * @np: a pointer to a device tree node.
1174 * @type: the thermal cooling device type.
1175 * @devdata: device private data.
1176 * @ops: standard thermal cooling devices callbacks.
1177 *
1178 * This function will register a cooling device with device tree node reference.
1179 * This interface function adds a new thermal cooling device (fan/processor/...)
1180 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1181 * to all the thermal zone devices registered at the same time.
1182 *
1183 * Return: a pointer to the created struct thermal_cooling_device or an
1184 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1185 */
1186 struct thermal_cooling_device *
thermal_of_cooling_device_register(struct device_node * np,const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1187 thermal_of_cooling_device_register(struct device_node *np,
1188 const char *type, void *devdata,
1189 const struct thermal_cooling_device_ops *ops)
1190 {
1191 return __thermal_cooling_device_register(np, type, devdata, ops);
1192 }
1193 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1194
thermal_cooling_device_release(struct device * dev,void * res)1195 static void thermal_cooling_device_release(struct device *dev, void *res)
1196 {
1197 thermal_cooling_device_unregister(
1198 *(struct thermal_cooling_device **)res);
1199 }
1200
1201 /**
1202 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1203 * device
1204 * @dev: a valid struct device pointer of a sensor device.
1205 * @np: a pointer to a device tree node.
1206 * @type: the thermal cooling device type.
1207 * @devdata: device private data.
1208 * @ops: standard thermal cooling devices callbacks.
1209 *
1210 * This function will register a cooling device with device tree node reference.
1211 * This interface function adds a new thermal cooling device (fan/processor/...)
1212 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1213 * to all the thermal zone devices registered at the same time.
1214 *
1215 * Return: a pointer to the created struct thermal_cooling_device or an
1216 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1217 */
1218 struct thermal_cooling_device *
devm_thermal_of_cooling_device_register(struct device * dev,struct device_node * np,char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1219 devm_thermal_of_cooling_device_register(struct device *dev,
1220 struct device_node *np,
1221 char *type, void *devdata,
1222 const struct thermal_cooling_device_ops *ops)
1223 {
1224 struct thermal_cooling_device **ptr, *tcd;
1225
1226 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1227 GFP_KERNEL);
1228 if (!ptr)
1229 return ERR_PTR(-ENOMEM);
1230
1231 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1232 if (IS_ERR(tcd)) {
1233 devres_free(ptr);
1234 return tcd;
1235 }
1236
1237 *ptr = tcd;
1238 devres_add(dev, ptr);
1239
1240 return tcd;
1241 }
1242 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1243
__unbind(struct thermal_zone_device * tz,int mask,struct thermal_cooling_device * cdev)1244 static void __unbind(struct thermal_zone_device *tz, int mask,
1245 struct thermal_cooling_device *cdev)
1246 {
1247 int i;
1248
1249 for (i = 0; i < tz->trips; i++)
1250 if (mask & (1 << i))
1251 thermal_zone_unbind_cooling_device(tz, i, cdev);
1252 }
1253
1254 /**
1255 * thermal_cooling_device_unregister - removes a thermal cooling device
1256 * @cdev: the thermal cooling device to remove.
1257 *
1258 * thermal_cooling_device_unregister() must be called when a registered
1259 * thermal cooling device is no longer needed.
1260 */
thermal_cooling_device_unregister(struct thermal_cooling_device * cdev)1261 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1262 {
1263 int i;
1264 const struct thermal_zone_params *tzp;
1265 struct thermal_zone_device *tz;
1266 struct thermal_cooling_device *pos = NULL;
1267
1268 if (!cdev)
1269 return;
1270
1271 mutex_lock(&thermal_list_lock);
1272 list_for_each_entry(pos, &thermal_cdev_list, node)
1273 if (pos == cdev)
1274 break;
1275 if (pos != cdev) {
1276 /* thermal cooling device not found */
1277 mutex_unlock(&thermal_list_lock);
1278 return;
1279 }
1280 list_del(&cdev->node);
1281
1282 /* Unbind all thermal zones associated with 'this' cdev */
1283 list_for_each_entry(tz, &thermal_tz_list, node) {
1284 if (tz->ops->unbind) {
1285 tz->ops->unbind(tz, cdev);
1286 continue;
1287 }
1288
1289 if (!tz->tzp || !tz->tzp->tbp)
1290 continue;
1291
1292 tzp = tz->tzp;
1293 for (i = 0; i < tzp->num_tbps; i++) {
1294 if (tzp->tbp[i].cdev == cdev) {
1295 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1296 tzp->tbp[i].cdev = NULL;
1297 }
1298 }
1299 }
1300
1301 mutex_unlock(&thermal_list_lock);
1302
1303 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1304 device_del(&cdev->device);
1305 thermal_cooling_device_destroy_sysfs(cdev);
1306 put_device(&cdev->device);
1307 }
1308 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1309
bind_tz(struct thermal_zone_device * tz)1310 static void bind_tz(struct thermal_zone_device *tz)
1311 {
1312 int i, ret;
1313 struct thermal_cooling_device *pos = NULL;
1314 const struct thermal_zone_params *tzp = tz->tzp;
1315
1316 if (!tzp && !tz->ops->bind)
1317 return;
1318
1319 mutex_lock(&thermal_list_lock);
1320
1321 /* If there is ops->bind, try to use ops->bind */
1322 if (tz->ops->bind) {
1323 list_for_each_entry(pos, &thermal_cdev_list, node) {
1324 ret = tz->ops->bind(tz, pos);
1325 if (ret)
1326 print_bind_err_msg(tz, pos, ret);
1327 }
1328 goto exit;
1329 }
1330
1331 if (!tzp || !tzp->tbp)
1332 goto exit;
1333
1334 list_for_each_entry(pos, &thermal_cdev_list, node) {
1335 for (i = 0; i < tzp->num_tbps; i++) {
1336 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1337 continue;
1338 if (tzp->tbp[i].match(tz, pos))
1339 continue;
1340 tzp->tbp[i].cdev = pos;
1341 __bind(tz, tzp->tbp[i].trip_mask, pos,
1342 tzp->tbp[i].binding_limits,
1343 tzp->tbp[i].weight);
1344 }
1345 }
1346 exit:
1347 mutex_unlock(&thermal_list_lock);
1348 }
1349
1350 /**
1351 * thermal_zone_device_register() - register a new thermal zone device
1352 * @type: the thermal zone device type
1353 * @trips: the number of trip points the thermal zone support
1354 * @mask: a bit string indicating the writeablility of trip points
1355 * @devdata: private device data
1356 * @ops: standard thermal zone device callbacks
1357 * @tzp: thermal zone platform parameters
1358 * @passive_delay: number of milliseconds to wait between polls when
1359 * performing passive cooling
1360 * @polling_delay: number of milliseconds to wait between polls when checking
1361 * whether trip points have been crossed (0 for interrupt
1362 * driven systems)
1363 *
1364 * This interface function adds a new thermal zone device (sensor) to
1365 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1366 * thermal cooling devices registered at the same time.
1367 * thermal_zone_device_unregister() must be called when the device is no
1368 * longer needed. The passive cooling depends on the .get_trend() return value.
1369 *
1370 * Return: a pointer to the created struct thermal_zone_device or an
1371 * in case of error, an ERR_PTR. Caller must check return value with
1372 * IS_ERR*() helpers.
1373 */
1374 struct thermal_zone_device *
thermal_zone_device_register(const char * type,int trips,int mask,void * devdata,struct thermal_zone_device_ops * ops,struct thermal_zone_params * tzp,int passive_delay,int polling_delay)1375 thermal_zone_device_register(const char *type, int trips, int mask,
1376 void *devdata, struct thermal_zone_device_ops *ops,
1377 struct thermal_zone_params *tzp, int passive_delay,
1378 int polling_delay)
1379 {
1380 struct thermal_zone_device *tz;
1381 enum thermal_trip_type trip_type;
1382 int trip_temp;
1383 int id;
1384 int result;
1385 int count;
1386 struct thermal_governor *governor;
1387
1388 if (!type || strlen(type) == 0) {
1389 pr_err("Error: No thermal zone type defined\n");
1390 return ERR_PTR(-EINVAL);
1391 }
1392
1393 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1394 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1395 type, THERMAL_NAME_LENGTH);
1396 return ERR_PTR(-EINVAL);
1397 }
1398
1399 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1400 pr_err("Error: Incorrect number of thermal trips\n");
1401 return ERR_PTR(-EINVAL);
1402 }
1403
1404 if (!ops) {
1405 pr_err("Error: Thermal zone device ops not defined\n");
1406 return ERR_PTR(-EINVAL);
1407 }
1408
1409 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1410 return ERR_PTR(-EINVAL);
1411
1412 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1413 if (!tz)
1414 return ERR_PTR(-ENOMEM);
1415
1416 INIT_LIST_HEAD(&tz->thermal_instances);
1417 ida_init(&tz->ida);
1418 mutex_init(&tz->lock);
1419 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1420 if (id < 0) {
1421 result = id;
1422 goto free_tz;
1423 }
1424
1425 tz->id = id;
1426 strlcpy(tz->type, type, sizeof(tz->type));
1427 tz->ops = ops;
1428 tz->tzp = tzp;
1429 tz->device.class = &thermal_class;
1430 tz->devdata = devdata;
1431 tz->trips = trips;
1432 tz->passive_delay = passive_delay;
1433 tz->polling_delay = polling_delay;
1434
1435 /* sys I/F */
1436 /* Add nodes that are always present via .groups */
1437 result = thermal_zone_create_device_groups(tz, mask);
1438 if (result)
1439 goto remove_id;
1440
1441 /* A new thermal zone needs to be updated anyway. */
1442 atomic_set(&tz->need_update, 1);
1443
1444 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1445 result = device_register(&tz->device);
1446 if (result)
1447 goto release_device;
1448
1449 for (count = 0; count < trips; count++) {
1450 if (tz->ops->get_trip_type(tz, count, &trip_type))
1451 set_bit(count, &tz->trips_disabled);
1452 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1453 set_bit(count, &tz->trips_disabled);
1454 /* Check for bogus trip points */
1455 if (trip_temp == 0)
1456 set_bit(count, &tz->trips_disabled);
1457 }
1458
1459 /* Update 'this' zone's governor information */
1460 mutex_lock(&thermal_governor_lock);
1461
1462 if (tz->tzp)
1463 governor = __find_governor(tz->tzp->governor_name);
1464 else
1465 governor = def_governor;
1466
1467 result = thermal_set_governor(tz, governor);
1468 if (result) {
1469 mutex_unlock(&thermal_governor_lock);
1470 goto unregister;
1471 }
1472
1473 mutex_unlock(&thermal_governor_lock);
1474
1475 if (!tz->tzp || !tz->tzp->no_hwmon) {
1476 result = thermal_add_hwmon_sysfs(tz);
1477 if (result)
1478 goto unregister;
1479 }
1480
1481 mutex_lock(&thermal_list_lock);
1482 list_add_tail(&tz->node, &thermal_tz_list);
1483 mutex_unlock(&thermal_list_lock);
1484
1485 /* Bind cooling devices for this zone */
1486 bind_tz(tz);
1487
1488 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1489
1490 thermal_zone_device_reset(tz);
1491 /* Update the new thermal zone and mark it as already updated. */
1492 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1493 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1494
1495 thermal_notify_tz_create(tz->id, tz->type);
1496
1497 return tz;
1498
1499 unregister:
1500 device_del(&tz->device);
1501 release_device:
1502 put_device(&tz->device);
1503 tz = NULL;
1504 remove_id:
1505 ida_simple_remove(&thermal_tz_ida, id);
1506 free_tz:
1507 kfree(tz);
1508 return ERR_PTR(result);
1509 }
1510 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1511
1512 /**
1513 * thermal_zone_device_unregister - removes the registered thermal zone device
1514 * @tz: the thermal zone device to remove
1515 */
thermal_zone_device_unregister(struct thermal_zone_device * tz)1516 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1517 {
1518 int i, tz_id;
1519 const struct thermal_zone_params *tzp;
1520 struct thermal_cooling_device *cdev;
1521 struct thermal_zone_device *pos = NULL;
1522
1523 if (!tz)
1524 return;
1525
1526 tzp = tz->tzp;
1527 tz_id = tz->id;
1528
1529 mutex_lock(&thermal_list_lock);
1530 list_for_each_entry(pos, &thermal_tz_list, node)
1531 if (pos == tz)
1532 break;
1533 if (pos != tz) {
1534 /* thermal zone device not found */
1535 mutex_unlock(&thermal_list_lock);
1536 return;
1537 }
1538 list_del(&tz->node);
1539
1540 /* Unbind all cdevs associated with 'this' thermal zone */
1541 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1542 if (tz->ops->unbind) {
1543 tz->ops->unbind(tz, cdev);
1544 continue;
1545 }
1546
1547 if (!tzp || !tzp->tbp)
1548 break;
1549
1550 for (i = 0; i < tzp->num_tbps; i++) {
1551 if (tzp->tbp[i].cdev == cdev) {
1552 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1553 tzp->tbp[i].cdev = NULL;
1554 }
1555 }
1556 }
1557
1558 mutex_unlock(&thermal_list_lock);
1559
1560 cancel_delayed_work_sync(&tz->poll_queue);
1561
1562 thermal_set_governor(tz, NULL);
1563
1564 thermal_remove_hwmon_sysfs(tz);
1565 ida_simple_remove(&thermal_tz_ida, tz->id);
1566 ida_destroy(&tz->ida);
1567 mutex_destroy(&tz->lock);
1568 device_unregister(&tz->device);
1569
1570 thermal_notify_tz_delete(tz_id);
1571 }
1572 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1573
1574 /**
1575 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1576 * @name: thermal zone name to fetch the temperature
1577 *
1578 * When only one zone is found with the passed name, returns a reference to it.
1579 *
1580 * Return: On success returns a reference to an unique thermal zone with
1581 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1582 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1583 */
thermal_zone_get_zone_by_name(const char * name)1584 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1585 {
1586 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1587 unsigned int found = 0;
1588
1589 if (!name)
1590 goto exit;
1591
1592 mutex_lock(&thermal_list_lock);
1593 list_for_each_entry(pos, &thermal_tz_list, node)
1594 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1595 found++;
1596 ref = pos;
1597 }
1598 mutex_unlock(&thermal_list_lock);
1599
1600 /* nothing has been found, thus an error code for it */
1601 if (found == 0)
1602 ref = ERR_PTR(-ENODEV);
1603 else if (found > 1)
1604 /* Success only when an unique zone is found */
1605 ref = ERR_PTR(-EEXIST);
1606
1607 exit:
1608 return ref;
1609 }
1610 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1611
thermal_pm_notify(struct notifier_block * nb,unsigned long mode,void * _unused)1612 static int thermal_pm_notify(struct notifier_block *nb,
1613 unsigned long mode, void *_unused)
1614 {
1615 struct thermal_zone_device *tz;
1616
1617 switch (mode) {
1618 case PM_HIBERNATION_PREPARE:
1619 case PM_RESTORE_PREPARE:
1620 case PM_SUSPEND_PREPARE:
1621 atomic_set(&in_suspend, 1);
1622 break;
1623 case PM_POST_HIBERNATION:
1624 case PM_POST_RESTORE:
1625 case PM_POST_SUSPEND:
1626 atomic_set(&in_suspend, 0);
1627 list_for_each_entry(tz, &thermal_tz_list, node) {
1628 if (!thermal_zone_device_is_enabled(tz))
1629 continue;
1630
1631 thermal_zone_device_init(tz);
1632 thermal_zone_device_update(tz,
1633 THERMAL_EVENT_UNSPECIFIED);
1634 }
1635 break;
1636 default:
1637 break;
1638 }
1639 return 0;
1640 }
1641
1642 static struct notifier_block thermal_pm_nb = {
1643 .notifier_call = thermal_pm_notify,
1644 };
1645
thermal_init(void)1646 static int __init thermal_init(void)
1647 {
1648 int result;
1649
1650 result = thermal_netlink_init();
1651 if (result)
1652 goto error;
1653
1654 result = thermal_register_governors();
1655 if (result)
1656 goto error;
1657
1658 result = class_register(&thermal_class);
1659 if (result)
1660 goto unregister_governors;
1661
1662 result = of_parse_thermal_zones();
1663 if (result)
1664 goto unregister_class;
1665
1666 result = register_pm_notifier(&thermal_pm_nb);
1667 if (result)
1668 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1669 result);
1670
1671 return 0;
1672
1673 unregister_class:
1674 class_unregister(&thermal_class);
1675 unregister_governors:
1676 thermal_unregister_governors();
1677 error:
1678 ida_destroy(&thermal_tz_ida);
1679 ida_destroy(&thermal_cdev_ida);
1680 mutex_destroy(&thermal_list_lock);
1681 mutex_destroy(&thermal_governor_lock);
1682 mutex_destroy(&poweroff_lock);
1683 return result;
1684 }
1685 postcore_initcall(thermal_init);
1686