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 ssize_t size = PAGE_SIZE;
228
229 mutex_lock(&thermal_governor_lock);
230
231 list_for_each_entry(pos, &thermal_governor_list, governor_list) {
232 size = PAGE_SIZE - count;
233 count += scnprintf(buf + count, size, "%s ", pos->name);
234 }
235 count += scnprintf(buf + count, size, "\n");
236
237 mutex_unlock(&thermal_governor_lock);
238
239 return count;
240 }
241
thermal_unregister_governors(void)242 static void __init thermal_unregister_governors(void)
243 {
244 struct thermal_governor **governor;
245
246 for_each_governor_table(governor)
247 thermal_unregister_governor(*governor);
248 }
249
thermal_register_governors(void)250 static int __init thermal_register_governors(void)
251 {
252 int ret = 0;
253 struct thermal_governor **governor;
254
255 for_each_governor_table(governor) {
256 ret = thermal_register_governor(*governor);
257 if (ret) {
258 pr_err("Failed to register governor: '%s'",
259 (*governor)->name);
260 break;
261 }
262
263 pr_info("Registered thermal governor '%s'",
264 (*governor)->name);
265 }
266
267 if (ret) {
268 struct thermal_governor **gov;
269
270 for_each_governor_table(gov) {
271 if (gov == governor)
272 break;
273 thermal_unregister_governor(*gov);
274 }
275 }
276
277 return ret;
278 }
279
280 /*
281 * Zone update section: main control loop applied to each zone while monitoring
282 *
283 * in polling mode. The monitoring is done using a workqueue.
284 * Same update may be done on a zone by calling thermal_zone_device_update().
285 *
286 * An update means:
287 * - Non-critical trips will invoke the governor responsible for that zone;
288 * - Hot trips will produce a notification to userspace;
289 * - Critical trip point will cause a system shutdown.
290 */
thermal_zone_device_set_polling(struct thermal_zone_device * tz,unsigned long delay)291 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
292 unsigned long delay)
293 {
294 if (delay)
295 mod_delayed_work(system_freezable_power_efficient_wq,
296 &tz->poll_queue, delay);
297 else
298 cancel_delayed_work(&tz->poll_queue);
299 }
300
should_stop_polling(struct thermal_zone_device * tz)301 static inline bool should_stop_polling(struct thermal_zone_device *tz)
302 {
303 return !thermal_zone_device_is_enabled(tz);
304 }
305
monitor_thermal_zone(struct thermal_zone_device * tz)306 static void monitor_thermal_zone(struct thermal_zone_device *tz)
307 {
308 bool stop;
309
310 stop = should_stop_polling(tz);
311
312 mutex_lock(&tz->lock);
313
314 if (!stop && tz->passive)
315 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
316 else if (!stop && tz->polling_delay_jiffies)
317 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
318 else
319 thermal_zone_device_set_polling(tz, 0);
320
321 mutex_unlock(&tz->lock);
322 }
323
handle_non_critical_trips(struct thermal_zone_device * tz,int trip)324 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
325 {
326 tz->governor ? tz->governor->throttle(tz, trip) :
327 def_governor->throttle(tz, trip);
328 }
329
330 /**
331 * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
332 * @work: work_struct associated with the emergency poweroff function
333 *
334 * This function is called in very critical situations to force
335 * a kernel poweroff after a configurable timeout value.
336 */
thermal_emergency_poweroff_func(struct work_struct * work)337 static void thermal_emergency_poweroff_func(struct work_struct *work)
338 {
339 /*
340 * We have reached here after the emergency thermal shutdown
341 * Waiting period has expired. This means orderly_poweroff has
342 * not been able to shut off the system for some reason.
343 * Try to shut down the system immediately using kernel_power_off
344 * if populated
345 */
346 WARN(1, "Attempting kernel_power_off: Temperature too high\n");
347 kernel_power_off();
348
349 /*
350 * Worst of the worst case trigger emergency restart
351 */
352 WARN(1, "Attempting emergency_restart: Temperature too high\n");
353 emergency_restart();
354 }
355
356 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
357 thermal_emergency_poweroff_func);
358
359 /**
360 * thermal_emergency_poweroff - Trigger an emergency system poweroff
361 *
362 * This may be called from any critical situation to trigger a system shutdown
363 * after a known period of time. By default this is not scheduled.
364 */
thermal_emergency_poweroff(void)365 static void thermal_emergency_poweroff(void)
366 {
367 int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
368 /*
369 * poweroff_delay_ms must be a carefully profiled positive value.
370 * Its a must for thermal_emergency_poweroff_work to be scheduled
371 */
372 if (poweroff_delay_ms <= 0)
373 return;
374 schedule_delayed_work(&thermal_emergency_poweroff_work,
375 msecs_to_jiffies(poweroff_delay_ms));
376 }
377
thermal_zone_device_critical(struct thermal_zone_device * tz)378 void thermal_zone_device_critical(struct thermal_zone_device *tz)
379 {
380 dev_emerg(&tz->device, "%s: critical temperature reached, "
381 "shutting down\n", tz->type);
382
383 mutex_lock(&poweroff_lock);
384 if (!power_off_triggered) {
385 /*
386 * Queue a backup emergency shutdown in the event of
387 * orderly_poweroff failure
388 */
389 thermal_emergency_poweroff();
390 orderly_poweroff(true);
391 power_off_triggered = true;
392 }
393 mutex_unlock(&poweroff_lock);
394 }
395 EXPORT_SYMBOL(thermal_zone_device_critical);
396
handle_critical_trips(struct thermal_zone_device * tz,int trip,enum thermal_trip_type trip_type)397 static void handle_critical_trips(struct thermal_zone_device *tz,
398 int trip, enum thermal_trip_type trip_type)
399 {
400 int trip_temp;
401
402 tz->ops->get_trip_temp(tz, trip, &trip_temp);
403
404 /* If we have not crossed the trip_temp, we do not care. */
405 if (trip_temp <= 0 || tz->temperature < trip_temp)
406 return;
407
408 trace_thermal_zone_trip(tz, trip, trip_type);
409
410 if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
411 tz->ops->hot(tz);
412 else if (trip_type == THERMAL_TRIP_CRITICAL)
413 tz->ops->critical(tz);
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 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
478 pos->initialized = false;
479 }
480
thermal_zone_device_set_mode(struct thermal_zone_device * tz,enum thermal_device_mode mode)481 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
482 enum thermal_device_mode mode)
483 {
484 int ret = 0;
485
486 mutex_lock(&tz->lock);
487
488 /* do nothing if mode isn't changing */
489 if (mode == tz->mode) {
490 mutex_unlock(&tz->lock);
491
492 return ret;
493 }
494
495 if (tz->ops->change_mode)
496 ret = tz->ops->change_mode(tz, mode);
497
498 if (!ret)
499 tz->mode = mode;
500
501 mutex_unlock(&tz->lock);
502
503 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
504
505 if (mode == THERMAL_DEVICE_ENABLED)
506 thermal_notify_tz_enable(tz->id);
507 else
508 thermal_notify_tz_disable(tz->id);
509
510 return ret;
511 }
512
thermal_zone_device_enable(struct thermal_zone_device * tz)513 int thermal_zone_device_enable(struct thermal_zone_device *tz)
514 {
515 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
516 }
517 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
518
thermal_zone_device_disable(struct thermal_zone_device * tz)519 int thermal_zone_device_disable(struct thermal_zone_device *tz)
520 {
521 return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
522 }
523 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
524
thermal_zone_device_is_enabled(struct thermal_zone_device * tz)525 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
526 {
527 enum thermal_device_mode mode;
528
529 mutex_lock(&tz->lock);
530
531 mode = tz->mode;
532
533 mutex_unlock(&tz->lock);
534
535 return mode == THERMAL_DEVICE_ENABLED;
536 }
537
thermal_zone_device_update(struct thermal_zone_device * tz,enum thermal_notify_event event)538 void thermal_zone_device_update(struct thermal_zone_device *tz,
539 enum thermal_notify_event event)
540 {
541 int count;
542
543 if (should_stop_polling(tz))
544 return;
545
546 if (atomic_read(&in_suspend))
547 return;
548
549 if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
550 "'get_temp' ops set\n", __func__))
551 return;
552
553 update_temperature(tz);
554
555 thermal_zone_set_trips(tz);
556
557 tz->notify_event = event;
558
559 for (count = 0; count < tz->trips; count++)
560 handle_thermal_trip(tz, count);
561 }
562 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
563
thermal_zone_device_check(struct work_struct * work)564 static void thermal_zone_device_check(struct work_struct *work)
565 {
566 struct thermal_zone_device *tz = container_of(work, struct
567 thermal_zone_device,
568 poll_queue.work);
569 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
570 }
571
for_each_thermal_governor(int (* cb)(struct thermal_governor *,void *),void * data)572 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
573 void *data)
574 {
575 struct thermal_governor *gov;
576 int ret = 0;
577
578 mutex_lock(&thermal_governor_lock);
579 list_for_each_entry(gov, &thermal_governor_list, governor_list) {
580 ret = cb(gov, data);
581 if (ret)
582 break;
583 }
584 mutex_unlock(&thermal_governor_lock);
585
586 return ret;
587 }
588
for_each_thermal_cooling_device(int (* cb)(struct thermal_cooling_device *,void *),void * data)589 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
590 void *), void *data)
591 {
592 struct thermal_cooling_device *cdev;
593 int ret = 0;
594
595 mutex_lock(&thermal_list_lock);
596 list_for_each_entry(cdev, &thermal_cdev_list, node) {
597 ret = cb(cdev, data);
598 if (ret)
599 break;
600 }
601 mutex_unlock(&thermal_list_lock);
602
603 return ret;
604 }
605
for_each_thermal_zone(int (* cb)(struct thermal_zone_device *,void *),void * data)606 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
607 void *data)
608 {
609 struct thermal_zone_device *tz;
610 int ret = 0;
611
612 mutex_lock(&thermal_list_lock);
613 list_for_each_entry(tz, &thermal_tz_list, node) {
614 ret = cb(tz, data);
615 if (ret)
616 break;
617 }
618 mutex_unlock(&thermal_list_lock);
619
620 return ret;
621 }
622
thermal_zone_get_by_id(int id)623 struct thermal_zone_device *thermal_zone_get_by_id(int id)
624 {
625 struct thermal_zone_device *tz, *match = NULL;
626
627 mutex_lock(&thermal_list_lock);
628 list_for_each_entry(tz, &thermal_tz_list, node) {
629 if (tz->id == id) {
630 match = tz;
631 break;
632 }
633 }
634 mutex_unlock(&thermal_list_lock);
635
636 return match;
637 }
638
639 /*
640 * Device management section: cooling devices, zones devices, and binding
641 *
642 * Set of functions provided by the thermal core for:
643 * - cooling devices lifecycle: registration, unregistration,
644 * binding, and unbinding.
645 * - thermal zone devices lifecycle: registration, unregistration,
646 * binding, and unbinding.
647 */
648
649 /**
650 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
651 * @tz: pointer to struct thermal_zone_device
652 * @trip: indicates which trip point the cooling devices is
653 * associated with in this thermal zone.
654 * @cdev: pointer to struct thermal_cooling_device
655 * @upper: the Maximum cooling state for this trip point.
656 * THERMAL_NO_LIMIT means no upper limit,
657 * and the cooling device can be in max_state.
658 * @lower: the Minimum cooling state can be used for this trip point.
659 * THERMAL_NO_LIMIT means no lower limit,
660 * and the cooling device can be in cooling state 0.
661 * @weight: The weight of the cooling device to be bound to the
662 * thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
663 * default value
664 *
665 * This interface function bind a thermal cooling device to the certain trip
666 * point of a thermal zone device.
667 * This function is usually called in the thermal zone device .bind callback.
668 *
669 * Return: 0 on success, the proper error value otherwise.
670 */
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)671 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
672 int trip,
673 struct thermal_cooling_device *cdev,
674 unsigned long upper, unsigned long lower,
675 unsigned int weight)
676 {
677 struct thermal_instance *dev;
678 struct thermal_instance *pos;
679 struct thermal_zone_device *pos1;
680 struct thermal_cooling_device *pos2;
681 unsigned long max_state;
682 int result, ret;
683
684 if (trip >= tz->trips || trip < 0)
685 return -EINVAL;
686
687 list_for_each_entry(pos1, &thermal_tz_list, node) {
688 if (pos1 == tz)
689 break;
690 }
691 list_for_each_entry(pos2, &thermal_cdev_list, node) {
692 if (pos2 == cdev)
693 break;
694 }
695
696 if (tz != pos1 || cdev != pos2)
697 return -EINVAL;
698
699 ret = cdev->ops->get_max_state(cdev, &max_state);
700 if (ret)
701 return ret;
702
703 /* lower default 0, upper default max_state */
704 lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
705 upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
706
707 if (lower > upper || upper > max_state)
708 return -EINVAL;
709
710 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
711 if (!dev)
712 return -ENOMEM;
713 dev->tz = tz;
714 dev->cdev = cdev;
715 dev->trip = trip;
716 dev->upper = upper;
717 dev->lower = lower;
718 dev->target = THERMAL_NO_TARGET;
719 dev->weight = weight;
720
721 result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
722 if (result < 0)
723 goto free_mem;
724
725 dev->id = result;
726 sprintf(dev->name, "cdev%d", dev->id);
727 result =
728 sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
729 if (result)
730 goto release_ida;
731
732 sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
733 sysfs_attr_init(&dev->attr.attr);
734 dev->attr.attr.name = dev->attr_name;
735 dev->attr.attr.mode = 0444;
736 dev->attr.show = trip_point_show;
737 result = device_create_file(&tz->device, &dev->attr);
738 if (result)
739 goto remove_symbol_link;
740
741 sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
742 sysfs_attr_init(&dev->weight_attr.attr);
743 dev->weight_attr.attr.name = dev->weight_attr_name;
744 dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
745 dev->weight_attr.show = weight_show;
746 dev->weight_attr.store = weight_store;
747 result = device_create_file(&tz->device, &dev->weight_attr);
748 if (result)
749 goto remove_trip_file;
750
751 mutex_lock(&tz->lock);
752 mutex_lock(&cdev->lock);
753 list_for_each_entry(pos, &tz->thermal_instances, tz_node)
754 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
755 result = -EEXIST;
756 break;
757 }
758 if (!result) {
759 list_add_tail(&dev->tz_node, &tz->thermal_instances);
760 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
761 atomic_set(&tz->need_update, 1);
762 }
763 mutex_unlock(&cdev->lock);
764 mutex_unlock(&tz->lock);
765
766 if (!result)
767 return 0;
768
769 device_remove_file(&tz->device, &dev->weight_attr);
770 remove_trip_file:
771 device_remove_file(&tz->device, &dev->attr);
772 remove_symbol_link:
773 sysfs_remove_link(&tz->device.kobj, dev->name);
774 release_ida:
775 ida_simple_remove(&tz->ida, dev->id);
776 free_mem:
777 kfree(dev);
778 return result;
779 }
780 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
781
782 /**
783 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
784 * thermal zone.
785 * @tz: pointer to a struct thermal_zone_device.
786 * @trip: indicates which trip point the cooling devices is
787 * associated with in this thermal zone.
788 * @cdev: pointer to a struct thermal_cooling_device.
789 *
790 * This interface function unbind a thermal cooling device from the certain
791 * trip point of a thermal zone device.
792 * This function is usually called in the thermal zone device .unbind callback.
793 *
794 * Return: 0 on success, the proper error value otherwise.
795 */
thermal_zone_unbind_cooling_device(struct thermal_zone_device * tz,int trip,struct thermal_cooling_device * cdev)796 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
797 int trip,
798 struct thermal_cooling_device *cdev)
799 {
800 struct thermal_instance *pos, *next;
801
802 mutex_lock(&tz->lock);
803 mutex_lock(&cdev->lock);
804 list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
805 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
806 list_del(&pos->tz_node);
807 list_del(&pos->cdev_node);
808 mutex_unlock(&cdev->lock);
809 mutex_unlock(&tz->lock);
810 goto unbind;
811 }
812 }
813 mutex_unlock(&cdev->lock);
814 mutex_unlock(&tz->lock);
815
816 return -ENODEV;
817
818 unbind:
819 device_remove_file(&tz->device, &pos->weight_attr);
820 device_remove_file(&tz->device, &pos->attr);
821 sysfs_remove_link(&tz->device.kobj, pos->name);
822 ida_simple_remove(&tz->ida, pos->id);
823 kfree(pos);
824 return 0;
825 }
826 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
827
thermal_release(struct device * dev)828 static void thermal_release(struct device *dev)
829 {
830 struct thermal_zone_device *tz;
831 struct thermal_cooling_device *cdev;
832
833 if (!strncmp(dev_name(dev), "thermal_zone",
834 sizeof("thermal_zone") - 1)) {
835 tz = to_thermal_zone(dev);
836 thermal_zone_destroy_device_groups(tz);
837 kfree(tz);
838 } else if (!strncmp(dev_name(dev), "cooling_device",
839 sizeof("cooling_device") - 1)) {
840 cdev = to_cooling_device(dev);
841 kfree(cdev);
842 }
843 }
844
845 static struct class thermal_class = {
846 .name = "thermal",
847 .dev_release = thermal_release,
848 };
849
850 static inline
print_bind_err_msg(struct thermal_zone_device * tz,struct thermal_cooling_device * cdev,int ret)851 void print_bind_err_msg(struct thermal_zone_device *tz,
852 struct thermal_cooling_device *cdev, int ret)
853 {
854 dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
855 tz->type, cdev->type, ret);
856 }
857
__bind(struct thermal_zone_device * tz,int mask,struct thermal_cooling_device * cdev,unsigned long * limits,unsigned int weight)858 static void __bind(struct thermal_zone_device *tz, int mask,
859 struct thermal_cooling_device *cdev,
860 unsigned long *limits,
861 unsigned int weight)
862 {
863 int i, ret;
864
865 for (i = 0; i < tz->trips; i++) {
866 if (mask & (1 << i)) {
867 unsigned long upper, lower;
868
869 upper = THERMAL_NO_LIMIT;
870 lower = THERMAL_NO_LIMIT;
871 if (limits) {
872 lower = limits[i * 2];
873 upper = limits[i * 2 + 1];
874 }
875 ret = thermal_zone_bind_cooling_device(tz, i, cdev,
876 upper, lower,
877 weight);
878 if (ret)
879 print_bind_err_msg(tz, cdev, ret);
880 }
881 }
882 }
883
bind_cdev(struct thermal_cooling_device * cdev)884 static void bind_cdev(struct thermal_cooling_device *cdev)
885 {
886 int i, ret;
887 const struct thermal_zone_params *tzp;
888 struct thermal_zone_device *pos = NULL;
889
890 mutex_lock(&thermal_list_lock);
891
892 list_for_each_entry(pos, &thermal_tz_list, node) {
893 if (!pos->tzp && !pos->ops->bind)
894 continue;
895
896 if (pos->ops->bind) {
897 ret = pos->ops->bind(pos, cdev);
898 if (ret)
899 print_bind_err_msg(pos, cdev, ret);
900 continue;
901 }
902
903 tzp = pos->tzp;
904 if (!tzp || !tzp->tbp)
905 continue;
906
907 for (i = 0; i < tzp->num_tbps; i++) {
908 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
909 continue;
910 if (tzp->tbp[i].match(pos, cdev))
911 continue;
912 tzp->tbp[i].cdev = cdev;
913 __bind(pos, tzp->tbp[i].trip_mask, cdev,
914 tzp->tbp[i].binding_limits,
915 tzp->tbp[i].weight);
916 }
917 }
918
919 mutex_unlock(&thermal_list_lock);
920 }
921
922 /**
923 * __thermal_cooling_device_register() - register a new thermal cooling device
924 * @np: a pointer to a device tree node.
925 * @type: the thermal cooling device type.
926 * @devdata: device private data.
927 * @ops: standard thermal cooling devices callbacks.
928 *
929 * This interface function adds a new thermal cooling device (fan/processor/...)
930 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
931 * to all the thermal zone devices registered at the same time.
932 * It also gives the opportunity to link the cooling device to a device tree
933 * node, so that it can be bound to a thermal zone created out of device tree.
934 *
935 * Return: a pointer to the created struct thermal_cooling_device or an
936 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
937 */
938 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)939 __thermal_cooling_device_register(struct device_node *np,
940 const char *type, void *devdata,
941 const struct thermal_cooling_device_ops *ops)
942 {
943 struct thermal_cooling_device *cdev;
944 struct thermal_zone_device *pos = NULL;
945 int ret;
946
947 if (!ops || !ops->get_max_state || !ops->get_cur_state ||
948 !ops->set_cur_state)
949 return ERR_PTR(-EINVAL);
950
951 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
952 if (!cdev)
953 return ERR_PTR(-ENOMEM);
954
955 ret = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
956 if (ret < 0)
957 goto out_kfree_cdev;
958 cdev->id = ret;
959
960 cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
961 if (!cdev->type) {
962 ret = -ENOMEM;
963 goto out_ida_remove;
964 }
965
966 mutex_init(&cdev->lock);
967 INIT_LIST_HEAD(&cdev->thermal_instances);
968 cdev->np = np;
969 cdev->ops = ops;
970 cdev->updated = false;
971 cdev->device.class = &thermal_class;
972 cdev->devdata = devdata;
973 thermal_cooling_device_setup_sysfs(cdev);
974 dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
975 ret = device_register(&cdev->device);
976 if (ret)
977 goto out_kfree_type;
978
979 /* Add 'this' new cdev to the global cdev list */
980 mutex_lock(&thermal_list_lock);
981 list_add(&cdev->node, &thermal_cdev_list);
982 mutex_unlock(&thermal_list_lock);
983
984 /* Update binding information for 'this' new cdev */
985 bind_cdev(cdev);
986
987 mutex_lock(&thermal_list_lock);
988 list_for_each_entry(pos, &thermal_tz_list, node)
989 if (atomic_cmpxchg(&pos->need_update, 1, 0))
990 thermal_zone_device_update(pos,
991 THERMAL_EVENT_UNSPECIFIED);
992 mutex_unlock(&thermal_list_lock);
993
994 return cdev;
995
996 out_kfree_type:
997 kfree(cdev->type);
998 put_device(&cdev->device);
999 out_ida_remove:
1000 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1001 out_kfree_cdev:
1002 kfree(cdev);
1003 return ERR_PTR(ret);
1004 }
1005
1006 /**
1007 * thermal_cooling_device_register() - register a new thermal cooling device
1008 * @type: the thermal cooling device type.
1009 * @devdata: device private data.
1010 * @ops: standard thermal cooling devices callbacks.
1011 *
1012 * This interface function adds a new thermal cooling device (fan/processor/...)
1013 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1014 * to all the thermal zone devices registered at the same time.
1015 *
1016 * Return: a pointer to the created struct thermal_cooling_device or an
1017 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1018 */
1019 struct thermal_cooling_device *
thermal_cooling_device_register(const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1020 thermal_cooling_device_register(const char *type, void *devdata,
1021 const struct thermal_cooling_device_ops *ops)
1022 {
1023 return __thermal_cooling_device_register(NULL, type, devdata, ops);
1024 }
1025 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1026
1027 /**
1028 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1029 * @np: a pointer to a device tree node.
1030 * @type: the thermal cooling device type.
1031 * @devdata: device private data.
1032 * @ops: standard thermal cooling devices callbacks.
1033 *
1034 * This function will register a cooling device with device tree node reference.
1035 * This interface function adds a new thermal cooling device (fan/processor/...)
1036 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1037 * to all the thermal zone devices registered at the same time.
1038 *
1039 * Return: a pointer to the created struct thermal_cooling_device or an
1040 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1041 */
1042 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)1043 thermal_of_cooling_device_register(struct device_node *np,
1044 const char *type, void *devdata,
1045 const struct thermal_cooling_device_ops *ops)
1046 {
1047 return __thermal_cooling_device_register(np, type, devdata, ops);
1048 }
1049 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1050
thermal_cooling_device_release(struct device * dev,void * res)1051 static void thermal_cooling_device_release(struct device *dev, void *res)
1052 {
1053 thermal_cooling_device_unregister(
1054 *(struct thermal_cooling_device **)res);
1055 }
1056
1057 /**
1058 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1059 * device
1060 * @dev: a valid struct device pointer of a sensor device.
1061 * @np: a pointer to a device tree node.
1062 * @type: the thermal cooling device type.
1063 * @devdata: device private data.
1064 * @ops: standard thermal cooling devices callbacks.
1065 *
1066 * This function will register a cooling device with device tree node reference.
1067 * This interface function adds a new thermal cooling device (fan/processor/...)
1068 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1069 * to all the thermal zone devices registered at the same time.
1070 *
1071 * Return: a pointer to the created struct thermal_cooling_device or an
1072 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1073 */
1074 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)1075 devm_thermal_of_cooling_device_register(struct device *dev,
1076 struct device_node *np,
1077 char *type, void *devdata,
1078 const struct thermal_cooling_device_ops *ops)
1079 {
1080 struct thermal_cooling_device **ptr, *tcd;
1081
1082 ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1083 GFP_KERNEL);
1084 if (!ptr)
1085 return ERR_PTR(-ENOMEM);
1086
1087 tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1088 if (IS_ERR(tcd)) {
1089 devres_free(ptr);
1090 return tcd;
1091 }
1092
1093 *ptr = tcd;
1094 devres_add(dev, ptr);
1095
1096 return tcd;
1097 }
1098 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1099
__unbind(struct thermal_zone_device * tz,int mask,struct thermal_cooling_device * cdev)1100 static void __unbind(struct thermal_zone_device *tz, int mask,
1101 struct thermal_cooling_device *cdev)
1102 {
1103 int i;
1104
1105 for (i = 0; i < tz->trips; i++)
1106 if (mask & (1 << i))
1107 thermal_zone_unbind_cooling_device(tz, i, cdev);
1108 }
1109
1110 /**
1111 * thermal_cooling_device_unregister - removes a thermal cooling device
1112 * @cdev: the thermal cooling device to remove.
1113 *
1114 * thermal_cooling_device_unregister() must be called when a registered
1115 * thermal cooling device is no longer needed.
1116 */
thermal_cooling_device_unregister(struct thermal_cooling_device * cdev)1117 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1118 {
1119 int i;
1120 const struct thermal_zone_params *tzp;
1121 struct thermal_zone_device *tz;
1122 struct thermal_cooling_device *pos = NULL;
1123
1124 if (!cdev)
1125 return;
1126
1127 mutex_lock(&thermal_list_lock);
1128 list_for_each_entry(pos, &thermal_cdev_list, node)
1129 if (pos == cdev)
1130 break;
1131 if (pos != cdev) {
1132 /* thermal cooling device not found */
1133 mutex_unlock(&thermal_list_lock);
1134 return;
1135 }
1136 list_del(&cdev->node);
1137
1138 /* Unbind all thermal zones associated with 'this' cdev */
1139 list_for_each_entry(tz, &thermal_tz_list, node) {
1140 if (tz->ops->unbind) {
1141 tz->ops->unbind(tz, cdev);
1142 continue;
1143 }
1144
1145 if (!tz->tzp || !tz->tzp->tbp)
1146 continue;
1147
1148 tzp = tz->tzp;
1149 for (i = 0; i < tzp->num_tbps; i++) {
1150 if (tzp->tbp[i].cdev == cdev) {
1151 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1152 tzp->tbp[i].cdev = NULL;
1153 }
1154 }
1155 }
1156
1157 mutex_unlock(&thermal_list_lock);
1158
1159 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1160 device_del(&cdev->device);
1161 thermal_cooling_device_destroy_sysfs(cdev);
1162 kfree(cdev->type);
1163 put_device(&cdev->device);
1164 }
1165 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1166
bind_tz(struct thermal_zone_device * tz)1167 static void bind_tz(struct thermal_zone_device *tz)
1168 {
1169 int i, ret;
1170 struct thermal_cooling_device *pos = NULL;
1171 const struct thermal_zone_params *tzp = tz->tzp;
1172
1173 if (!tzp && !tz->ops->bind)
1174 return;
1175
1176 mutex_lock(&thermal_list_lock);
1177
1178 /* If there is ops->bind, try to use ops->bind */
1179 if (tz->ops->bind) {
1180 list_for_each_entry(pos, &thermal_cdev_list, node) {
1181 ret = tz->ops->bind(tz, pos);
1182 if (ret)
1183 print_bind_err_msg(tz, pos, ret);
1184 }
1185 goto exit;
1186 }
1187
1188 if (!tzp || !tzp->tbp)
1189 goto exit;
1190
1191 list_for_each_entry(pos, &thermal_cdev_list, node) {
1192 for (i = 0; i < tzp->num_tbps; i++) {
1193 if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1194 continue;
1195 if (tzp->tbp[i].match(tz, pos))
1196 continue;
1197 tzp->tbp[i].cdev = pos;
1198 __bind(tz, tzp->tbp[i].trip_mask, pos,
1199 tzp->tbp[i].binding_limits,
1200 tzp->tbp[i].weight);
1201 }
1202 }
1203 exit:
1204 mutex_unlock(&thermal_list_lock);
1205 }
1206
1207 /**
1208 * thermal_zone_device_register() - register a new thermal zone device
1209 * @type: the thermal zone device type
1210 * @trips: the number of trip points the thermal zone support
1211 * @mask: a bit string indicating the writeablility of trip points
1212 * @devdata: private device data
1213 * @ops: standard thermal zone device callbacks
1214 * @tzp: thermal zone platform parameters
1215 * @passive_delay: number of milliseconds to wait between polls when
1216 * performing passive cooling
1217 * @polling_delay: number of milliseconds to wait between polls when checking
1218 * whether trip points have been crossed (0 for interrupt
1219 * driven systems)
1220 *
1221 * This interface function adds a new thermal zone device (sensor) to
1222 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1223 * thermal cooling devices registered at the same time.
1224 * thermal_zone_device_unregister() must be called when the device is no
1225 * longer needed. The passive cooling depends on the .get_trend() return value.
1226 *
1227 * Return: a pointer to the created struct thermal_zone_device or an
1228 * in case of error, an ERR_PTR. Caller must check return value with
1229 * IS_ERR*() helpers.
1230 */
1231 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)1232 thermal_zone_device_register(const char *type, int trips, int mask,
1233 void *devdata, struct thermal_zone_device_ops *ops,
1234 struct thermal_zone_params *tzp, int passive_delay,
1235 int polling_delay)
1236 {
1237 struct thermal_zone_device *tz;
1238 enum thermal_trip_type trip_type;
1239 int trip_temp;
1240 int id;
1241 int result;
1242 int count;
1243 struct thermal_governor *governor;
1244
1245 if (!type || strlen(type) == 0) {
1246 pr_err("Error: No thermal zone type defined\n");
1247 return ERR_PTR(-EINVAL);
1248 }
1249
1250 if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1251 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1252 type, THERMAL_NAME_LENGTH);
1253 return ERR_PTR(-EINVAL);
1254 }
1255
1256 if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1257 pr_err("Error: Incorrect number of thermal trips\n");
1258 return ERR_PTR(-EINVAL);
1259 }
1260
1261 if (!ops) {
1262 pr_err("Error: Thermal zone device ops not defined\n");
1263 return ERR_PTR(-EINVAL);
1264 }
1265
1266 if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1267 return ERR_PTR(-EINVAL);
1268
1269 tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1270 if (!tz)
1271 return ERR_PTR(-ENOMEM);
1272
1273 INIT_LIST_HEAD(&tz->thermal_instances);
1274 ida_init(&tz->ida);
1275 mutex_init(&tz->lock);
1276 id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1277 if (id < 0) {
1278 result = id;
1279 goto free_tz;
1280 }
1281
1282 tz->id = id;
1283 strlcpy(tz->type, type, sizeof(tz->type));
1284
1285 if (!ops->critical)
1286 ops->critical = thermal_zone_device_critical;
1287
1288 tz->ops = ops;
1289 tz->tzp = tzp;
1290 tz->device.class = &thermal_class;
1291 tz->devdata = devdata;
1292 tz->trips = trips;
1293
1294 thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1295 thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1296
1297 /* sys I/F */
1298 /* Add nodes that are always present via .groups */
1299 result = thermal_zone_create_device_groups(tz, mask);
1300 if (result)
1301 goto remove_id;
1302
1303 /* A new thermal zone needs to be updated anyway. */
1304 atomic_set(&tz->need_update, 1);
1305
1306 dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1307 result = device_register(&tz->device);
1308 if (result)
1309 goto release_device;
1310
1311 for (count = 0; count < trips; count++) {
1312 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1313 tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1314 !trip_temp)
1315 set_bit(count, &tz->trips_disabled);
1316 }
1317
1318 /* Update 'this' zone's governor information */
1319 mutex_lock(&thermal_governor_lock);
1320
1321 if (tz->tzp)
1322 governor = __find_governor(tz->tzp->governor_name);
1323 else
1324 governor = def_governor;
1325
1326 result = thermal_set_governor(tz, governor);
1327 if (result) {
1328 mutex_unlock(&thermal_governor_lock);
1329 goto unregister;
1330 }
1331
1332 mutex_unlock(&thermal_governor_lock);
1333
1334 if (!tz->tzp || !tz->tzp->no_hwmon) {
1335 result = thermal_add_hwmon_sysfs(tz);
1336 if (result)
1337 goto unregister;
1338 }
1339
1340 mutex_lock(&thermal_list_lock);
1341 list_add_tail(&tz->node, &thermal_tz_list);
1342 mutex_unlock(&thermal_list_lock);
1343
1344 /* Bind cooling devices for this zone */
1345 bind_tz(tz);
1346
1347 INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1348
1349 thermal_zone_device_init(tz);
1350 /* Update the new thermal zone and mark it as already updated. */
1351 if (atomic_cmpxchg(&tz->need_update, 1, 0))
1352 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1353
1354 thermal_notify_tz_create(tz->id, tz->type);
1355
1356 return tz;
1357
1358 unregister:
1359 device_del(&tz->device);
1360 release_device:
1361 put_device(&tz->device);
1362 tz = NULL;
1363 remove_id:
1364 ida_simple_remove(&thermal_tz_ida, id);
1365 free_tz:
1366 kfree(tz);
1367 return ERR_PTR(result);
1368 }
1369 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1370
1371 /**
1372 * thermal_device_unregister - removes the registered thermal zone device
1373 * @tz: the thermal zone device to remove
1374 */
thermal_zone_device_unregister(struct thermal_zone_device * tz)1375 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1376 {
1377 int i, tz_id;
1378 const struct thermal_zone_params *tzp;
1379 struct thermal_cooling_device *cdev;
1380 struct thermal_zone_device *pos = NULL;
1381
1382 if (!tz)
1383 return;
1384
1385 tzp = tz->tzp;
1386 tz_id = tz->id;
1387
1388 mutex_lock(&thermal_list_lock);
1389 list_for_each_entry(pos, &thermal_tz_list, node)
1390 if (pos == tz)
1391 break;
1392 if (pos != tz) {
1393 /* thermal zone device not found */
1394 mutex_unlock(&thermal_list_lock);
1395 return;
1396 }
1397 list_del(&tz->node);
1398
1399 /* Unbind all cdevs associated with 'this' thermal zone */
1400 list_for_each_entry(cdev, &thermal_cdev_list, node) {
1401 if (tz->ops->unbind) {
1402 tz->ops->unbind(tz, cdev);
1403 continue;
1404 }
1405
1406 if (!tzp || !tzp->tbp)
1407 break;
1408
1409 for (i = 0; i < tzp->num_tbps; i++) {
1410 if (tzp->tbp[i].cdev == cdev) {
1411 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1412 tzp->tbp[i].cdev = NULL;
1413 }
1414 }
1415 }
1416
1417 mutex_unlock(&thermal_list_lock);
1418
1419 cancel_delayed_work_sync(&tz->poll_queue);
1420
1421 thermal_set_governor(tz, NULL);
1422
1423 thermal_remove_hwmon_sysfs(tz);
1424 ida_simple_remove(&thermal_tz_ida, tz->id);
1425 ida_destroy(&tz->ida);
1426 mutex_destroy(&tz->lock);
1427 device_unregister(&tz->device);
1428
1429 thermal_notify_tz_delete(tz_id);
1430 }
1431 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1432
1433 /**
1434 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1435 * @name: thermal zone name to fetch the temperature
1436 *
1437 * When only one zone is found with the passed name, returns a reference to it.
1438 *
1439 * Return: On success returns a reference to an unique thermal zone with
1440 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1441 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1442 */
thermal_zone_get_zone_by_name(const char * name)1443 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1444 {
1445 struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1446 unsigned int found = 0;
1447
1448 if (!name)
1449 goto exit;
1450
1451 mutex_lock(&thermal_list_lock);
1452 list_for_each_entry(pos, &thermal_tz_list, node)
1453 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1454 found++;
1455 ref = pos;
1456 }
1457 mutex_unlock(&thermal_list_lock);
1458
1459 /* nothing has been found, thus an error code for it */
1460 if (found == 0)
1461 ref = ERR_PTR(-ENODEV);
1462 else if (found > 1)
1463 /* Success only when an unique zone is found */
1464 ref = ERR_PTR(-EEXIST);
1465
1466 exit:
1467 return ref;
1468 }
1469 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1470
thermal_pm_notify(struct notifier_block * nb,unsigned long mode,void * _unused)1471 static int thermal_pm_notify(struct notifier_block *nb,
1472 unsigned long mode, void *_unused)
1473 {
1474 struct thermal_zone_device *tz;
1475
1476 switch (mode) {
1477 case PM_HIBERNATION_PREPARE:
1478 case PM_RESTORE_PREPARE:
1479 case PM_SUSPEND_PREPARE:
1480 atomic_set(&in_suspend, 1);
1481 break;
1482 case PM_POST_HIBERNATION:
1483 case PM_POST_RESTORE:
1484 case PM_POST_SUSPEND:
1485 atomic_set(&in_suspend, 0);
1486 list_for_each_entry(tz, &thermal_tz_list, node) {
1487 if (!thermal_zone_device_is_enabled(tz))
1488 continue;
1489
1490 thermal_zone_device_init(tz);
1491 thermal_zone_device_update(tz,
1492 THERMAL_EVENT_UNSPECIFIED);
1493 }
1494 break;
1495 default:
1496 break;
1497 }
1498 return 0;
1499 }
1500
1501 static struct notifier_block thermal_pm_nb = {
1502 .notifier_call = thermal_pm_notify,
1503 };
1504
thermal_init(void)1505 static int __init thermal_init(void)
1506 {
1507 int result;
1508
1509 result = thermal_netlink_init();
1510 if (result)
1511 goto error;
1512
1513 result = thermal_register_governors();
1514 if (result)
1515 goto error;
1516
1517 result = class_register(&thermal_class);
1518 if (result)
1519 goto unregister_governors;
1520
1521 result = of_parse_thermal_zones();
1522 if (result)
1523 goto unregister_class;
1524
1525 result = register_pm_notifier(&thermal_pm_nb);
1526 if (result)
1527 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1528 result);
1529
1530 return 0;
1531
1532 unregister_class:
1533 class_unregister(&thermal_class);
1534 unregister_governors:
1535 thermal_unregister_governors();
1536 error:
1537 ida_destroy(&thermal_tz_ida);
1538 ida_destroy(&thermal_cdev_ida);
1539 mutex_destroy(&thermal_list_lock);
1540 mutex_destroy(&thermal_governor_lock);
1541 mutex_destroy(&poweroff_lock);
1542 return result;
1543 }
1544 postcore_initcall(thermal_init);
1545