1// SPDX-License-Identifier: GPL-2.0
2/*
3 * thermal.c - sysfs interface of thermal devices
4 *
5 * Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
6 *
7 * Highly based on original thermal_core.c
8 * Copyright (C) 2008 Intel Corp
9 * Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
10 * Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
11 */
12
13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15#include <linux/sysfs.h>
16#include <linux/device.h>
17#include <linux/err.h>
18#include <linux/slab.h>
19#include <linux/string.h>
20#include <linux/jiffies.h>
21
22#include "thermal_core.h"
23
24/* sys I/F for thermal zone */
25
26static ssize_t
27type_show(struct device *dev, struct device_attribute *attr, char *buf)
28{
29 struct thermal_zone_device *tz = to_thermal_zone(dev);
30
31 return sprintf(buf, fmt: "%s\n", tz->type);
32}
33
34static ssize_t
35temp_show(struct device *dev, struct device_attribute *attr, char *buf)
36{
37 struct thermal_zone_device *tz = to_thermal_zone(dev);
38 int temperature, ret;
39
40 ret = thermal_zone_get_temp(tz, temp: &temperature);
41
42 if (ret)
43 return ret;
44
45 return sprintf(buf, fmt: "%d\n", temperature);
46}
47
48static ssize_t
49mode_show(struct device *dev, struct device_attribute *attr, char *buf)
50{
51 struct thermal_zone_device *tz = to_thermal_zone(dev);
52 int enabled;
53
54 mutex_lock(&tz->lock);
55 enabled = thermal_zone_device_is_enabled(tz);
56 mutex_unlock(lock: &tz->lock);
57
58 return sprintf(buf, fmt: "%s\n", enabled ? "enabled" : "disabled");
59}
60
61static ssize_t
62mode_store(struct device *dev, struct device_attribute *attr,
63 const char *buf, size_t count)
64{
65 struct thermal_zone_device *tz = to_thermal_zone(dev);
66 int result;
67
68 if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
69 result = thermal_zone_device_enable(tz);
70 else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
71 result = thermal_zone_device_disable(tz);
72 else
73 result = -EINVAL;
74
75 if (result)
76 return result;
77
78 return count;
79}
80
81static ssize_t
82trip_point_type_show(struct device *dev, struct device_attribute *attr,
83 char *buf)
84{
85 struct thermal_zone_device *tz = to_thermal_zone(dev);
86 struct thermal_trip trip;
87 int trip_id, result;
88
89 if (sscanf(attr->attr.name, "trip_point_%d_type", &trip_id) != 1)
90 return -EINVAL;
91
92 mutex_lock(&tz->lock);
93
94 if (device_is_registered(dev))
95 result = __thermal_zone_get_trip(tz, trip_id, trip: &trip);
96 else
97 result = -ENODEV;
98
99 mutex_unlock(lock: &tz->lock);
100
101 if (result)
102 return result;
103
104 switch (trip.type) {
105 case THERMAL_TRIP_CRITICAL:
106 return sprintf(buf, fmt: "critical\n");
107 case THERMAL_TRIP_HOT:
108 return sprintf(buf, fmt: "hot\n");
109 case THERMAL_TRIP_PASSIVE:
110 return sprintf(buf, fmt: "passive\n");
111 case THERMAL_TRIP_ACTIVE:
112 return sprintf(buf, fmt: "active\n");
113 default:
114 return sprintf(buf, fmt: "unknown\n");
115 }
116}
117
118static ssize_t
119trip_point_temp_store(struct device *dev, struct device_attribute *attr,
120 const char *buf, size_t count)
121{
122 struct thermal_zone_device *tz = to_thermal_zone(dev);
123 struct thermal_trip trip;
124 int trip_id, ret;
125
126 if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip_id) != 1)
127 return -EINVAL;
128
129 mutex_lock(&tz->lock);
130
131 if (!device_is_registered(dev)) {
132 ret = -ENODEV;
133 goto unlock;
134 }
135
136 ret = __thermal_zone_get_trip(tz, trip_id, trip: &trip);
137 if (ret)
138 goto unlock;
139
140 ret = kstrtoint(s: buf, base: 10, res: &trip.temperature);
141 if (ret)
142 goto unlock;
143
144 ret = thermal_zone_set_trip(tz, trip_id, trip: &trip);
145unlock:
146 mutex_unlock(lock: &tz->lock);
147
148 return ret ? ret : count;
149}
150
151static ssize_t
152trip_point_temp_show(struct device *dev, struct device_attribute *attr,
153 char *buf)
154{
155 struct thermal_zone_device *tz = to_thermal_zone(dev);
156 struct thermal_trip trip;
157 int trip_id, ret;
158
159 if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip_id) != 1)
160 return -EINVAL;
161
162 mutex_lock(&tz->lock);
163
164 if (device_is_registered(dev))
165 ret = __thermal_zone_get_trip(tz, trip_id, trip: &trip);
166 else
167 ret = -ENODEV;
168
169 mutex_unlock(lock: &tz->lock);
170
171 if (ret)
172 return ret;
173
174 return sprintf(buf, fmt: "%d\n", trip.temperature);
175}
176
177static ssize_t
178trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
179 const char *buf, size_t count)
180{
181 struct thermal_zone_device *tz = to_thermal_zone(dev);
182 struct thermal_trip trip;
183 int trip_id, ret;
184
185 if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
186 return -EINVAL;
187
188 mutex_lock(&tz->lock);
189
190 if (!device_is_registered(dev)) {
191 ret = -ENODEV;
192 goto unlock;
193 }
194
195 ret = __thermal_zone_get_trip(tz, trip_id, trip: &trip);
196 if (ret)
197 goto unlock;
198
199 ret = kstrtoint(s: buf, base: 10, res: &trip.hysteresis);
200 if (ret)
201 goto unlock;
202
203 ret = thermal_zone_set_trip(tz, trip_id, trip: &trip);
204unlock:
205 mutex_unlock(lock: &tz->lock);
206
207 return ret ? ret : count;
208}
209
210static ssize_t
211trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
212 char *buf)
213{
214 struct thermal_zone_device *tz = to_thermal_zone(dev);
215 struct thermal_trip trip;
216 int trip_id, ret;
217
218 if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
219 return -EINVAL;
220
221 mutex_lock(&tz->lock);
222
223 if (device_is_registered(dev))
224 ret = __thermal_zone_get_trip(tz, trip_id, trip: &trip);
225 else
226 ret = -ENODEV;
227
228 mutex_unlock(lock: &tz->lock);
229
230 return ret ? ret : sprintf(buf, fmt: "%d\n", trip.hysteresis);
231}
232
233static ssize_t
234policy_store(struct device *dev, struct device_attribute *attr,
235 const char *buf, size_t count)
236{
237 struct thermal_zone_device *tz = to_thermal_zone(dev);
238 char name[THERMAL_NAME_LENGTH];
239 int ret;
240
241 snprintf(buf: name, size: sizeof(name), fmt: "%s", buf);
242
243 ret = thermal_zone_device_set_policy(tz, name);
244 if (!ret)
245 ret = count;
246
247 return ret;
248}
249
250static ssize_t
251policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
252{
253 struct thermal_zone_device *tz = to_thermal_zone(dev);
254
255 return sprintf(buf, fmt: "%s\n", tz->governor->name);
256}
257
258static ssize_t
259available_policies_show(struct device *dev, struct device_attribute *devattr,
260 char *buf)
261{
262 return thermal_build_list_of_policies(buf);
263}
264
265#if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
266static ssize_t
267emul_temp_store(struct device *dev, struct device_attribute *attr,
268 const char *buf, size_t count)
269{
270 struct thermal_zone_device *tz = to_thermal_zone(dev);
271 int ret = 0;
272 int temperature;
273
274 if (kstrtoint(s: buf, base: 10, res: &temperature))
275 return -EINVAL;
276
277 mutex_lock(&tz->lock);
278
279 if (!device_is_registered(dev)) {
280 ret = -ENODEV;
281 goto unlock;
282 }
283
284 if (!tz->ops->set_emul_temp)
285 tz->emul_temperature = temperature;
286 else
287 ret = tz->ops->set_emul_temp(tz, temperature);
288
289 if (!ret)
290 __thermal_zone_device_update(tz, event: THERMAL_EVENT_UNSPECIFIED);
291
292unlock:
293 mutex_unlock(lock: &tz->lock);
294
295 return ret ? ret : count;
296}
297static DEVICE_ATTR_WO(emul_temp);
298#endif
299
300static ssize_t
301sustainable_power_show(struct device *dev, struct device_attribute *devattr,
302 char *buf)
303{
304 struct thermal_zone_device *tz = to_thermal_zone(dev);
305
306 if (tz->tzp)
307 return sprintf(buf, fmt: "%u\n", tz->tzp->sustainable_power);
308 else
309 return -EIO;
310}
311
312static ssize_t
313sustainable_power_store(struct device *dev, struct device_attribute *devattr,
314 const char *buf, size_t count)
315{
316 struct thermal_zone_device *tz = to_thermal_zone(dev);
317 u32 sustainable_power;
318
319 if (!tz->tzp)
320 return -EIO;
321
322 if (kstrtou32(s: buf, base: 10, res: &sustainable_power))
323 return -EINVAL;
324
325 tz->tzp->sustainable_power = sustainable_power;
326
327 return count;
328}
329
330#define create_s32_tzp_attr(name) \
331 static ssize_t \
332 name##_show(struct device *dev, struct device_attribute *devattr, \
333 char *buf) \
334 { \
335 struct thermal_zone_device *tz = to_thermal_zone(dev); \
336 \
337 if (tz->tzp) \
338 return sprintf(buf, "%d\n", tz->tzp->name); \
339 else \
340 return -EIO; \
341 } \
342 \
343 static ssize_t \
344 name##_store(struct device *dev, struct device_attribute *devattr, \
345 const char *buf, size_t count) \
346 { \
347 struct thermal_zone_device *tz = to_thermal_zone(dev); \
348 s32 value; \
349 \
350 if (!tz->tzp) \
351 return -EIO; \
352 \
353 if (kstrtos32(buf, 10, &value)) \
354 return -EINVAL; \
355 \
356 tz->tzp->name = value; \
357 \
358 return count; \
359 } \
360 static DEVICE_ATTR_RW(name)
361
362create_s32_tzp_attr(k_po);
363create_s32_tzp_attr(k_pu);
364create_s32_tzp_attr(k_i);
365create_s32_tzp_attr(k_d);
366create_s32_tzp_attr(integral_cutoff);
367create_s32_tzp_attr(slope);
368create_s32_tzp_attr(offset);
369#undef create_s32_tzp_attr
370
371/*
372 * These are thermal zone device attributes that will always be present.
373 * All the attributes created for tzp (create_s32_tzp_attr) also are always
374 * present on the sysfs interface.
375 */
376static DEVICE_ATTR_RO(type);
377static DEVICE_ATTR_RO(temp);
378static DEVICE_ATTR_RW(policy);
379static DEVICE_ATTR_RO(available_policies);
380static DEVICE_ATTR_RW(sustainable_power);
381
382/* These thermal zone device attributes are created based on conditions */
383static DEVICE_ATTR_RW(mode);
384
385/* These attributes are unconditionally added to a thermal zone */
386static struct attribute *thermal_zone_dev_attrs[] = {
387 &dev_attr_type.attr,
388 &dev_attr_temp.attr,
389#if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
390 &dev_attr_emul_temp.attr,
391#endif
392 &dev_attr_policy.attr,
393 &dev_attr_available_policies.attr,
394 &dev_attr_sustainable_power.attr,
395 &dev_attr_k_po.attr,
396 &dev_attr_k_pu.attr,
397 &dev_attr_k_i.attr,
398 &dev_attr_k_d.attr,
399 &dev_attr_integral_cutoff.attr,
400 &dev_attr_slope.attr,
401 &dev_attr_offset.attr,
402 NULL,
403};
404
405static const struct attribute_group thermal_zone_attribute_group = {
406 .attrs = thermal_zone_dev_attrs,
407};
408
409static struct attribute *thermal_zone_mode_attrs[] = {
410 &dev_attr_mode.attr,
411 NULL,
412};
413
414static const struct attribute_group thermal_zone_mode_attribute_group = {
415 .attrs = thermal_zone_mode_attrs,
416};
417
418static const struct attribute_group *thermal_zone_attribute_groups[] = {
419 &thermal_zone_attribute_group,
420 &thermal_zone_mode_attribute_group,
421 /* This is not NULL terminated as we create the group dynamically */
422};
423
424/**
425 * create_trip_attrs() - create attributes for trip points
426 * @tz: the thermal zone device
427 * @mask: Writeable trip point bitmap.
428 *
429 * helper function to instantiate sysfs entries for every trip
430 * point and its properties of a struct thermal_zone_device.
431 *
432 * Return: 0 on success, the proper error value otherwise.
433 */
434static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
435{
436 struct attribute **attrs;
437 int indx;
438
439 /* This function works only for zones with at least one trip */
440 if (tz->num_trips <= 0)
441 return -EINVAL;
442
443 tz->trip_type_attrs = kcalloc(n: tz->num_trips, size: sizeof(*tz->trip_type_attrs),
444 GFP_KERNEL);
445 if (!tz->trip_type_attrs)
446 return -ENOMEM;
447
448 tz->trip_temp_attrs = kcalloc(n: tz->num_trips, size: sizeof(*tz->trip_temp_attrs),
449 GFP_KERNEL);
450 if (!tz->trip_temp_attrs) {
451 kfree(objp: tz->trip_type_attrs);
452 return -ENOMEM;
453 }
454
455 tz->trip_hyst_attrs = kcalloc(n: tz->num_trips,
456 size: sizeof(*tz->trip_hyst_attrs),
457 GFP_KERNEL);
458 if (!tz->trip_hyst_attrs) {
459 kfree(objp: tz->trip_type_attrs);
460 kfree(objp: tz->trip_temp_attrs);
461 return -ENOMEM;
462 }
463
464 attrs = kcalloc(n: tz->num_trips * 3 + 1, size: sizeof(*attrs), GFP_KERNEL);
465 if (!attrs) {
466 kfree(objp: tz->trip_type_attrs);
467 kfree(objp: tz->trip_temp_attrs);
468 kfree(objp: tz->trip_hyst_attrs);
469 return -ENOMEM;
470 }
471
472 for (indx = 0; indx < tz->num_trips; indx++) {
473 /* create trip type attribute */
474 snprintf(buf: tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
475 fmt: "trip_point_%d_type", indx);
476
477 sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
478 tz->trip_type_attrs[indx].attr.attr.name =
479 tz->trip_type_attrs[indx].name;
480 tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
481 tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
482 attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
483
484 /* create trip temp attribute */
485 snprintf(buf: tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
486 fmt: "trip_point_%d_temp", indx);
487
488 sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
489 tz->trip_temp_attrs[indx].attr.attr.name =
490 tz->trip_temp_attrs[indx].name;
491 tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
492 tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
493 if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
494 mask & (1 << indx)) {
495 tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
496 tz->trip_temp_attrs[indx].attr.store =
497 trip_point_temp_store;
498 }
499 attrs[indx + tz->num_trips] = &tz->trip_temp_attrs[indx].attr.attr;
500
501 snprintf(buf: tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
502 fmt: "trip_point_%d_hyst", indx);
503
504 sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
505 tz->trip_hyst_attrs[indx].attr.attr.name =
506 tz->trip_hyst_attrs[indx].name;
507 tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
508 tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
509 if (tz->ops->set_trip_hyst) {
510 tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
511 tz->trip_hyst_attrs[indx].attr.store =
512 trip_point_hyst_store;
513 }
514 attrs[indx + tz->num_trips * 2] =
515 &tz->trip_hyst_attrs[indx].attr.attr;
516 }
517 attrs[tz->num_trips * 3] = NULL;
518
519 tz->trips_attribute_group.attrs = attrs;
520
521 return 0;
522}
523
524/**
525 * destroy_trip_attrs() - destroy attributes for trip points
526 * @tz: the thermal zone device
527 *
528 * helper function to free resources allocated by create_trip_attrs()
529 */
530static void destroy_trip_attrs(struct thermal_zone_device *tz)
531{
532 if (!tz)
533 return;
534
535 kfree(objp: tz->trip_type_attrs);
536 kfree(objp: tz->trip_temp_attrs);
537 kfree(objp: tz->trip_hyst_attrs);
538 kfree(objp: tz->trips_attribute_group.attrs);
539}
540
541int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
542 int mask)
543{
544 const struct attribute_group **groups;
545 int i, size, result;
546
547 /* we need one extra for trips and the NULL to terminate the array */
548 size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
549 /* This also takes care of API requirement to be NULL terminated */
550 groups = kcalloc(n: size, size: sizeof(*groups), GFP_KERNEL);
551 if (!groups)
552 return -ENOMEM;
553
554 for (i = 0; i < size - 2; i++)
555 groups[i] = thermal_zone_attribute_groups[i];
556
557 if (tz->num_trips) {
558 result = create_trip_attrs(tz, mask);
559 if (result) {
560 kfree(objp: groups);
561
562 return result;
563 }
564
565 groups[size - 2] = &tz->trips_attribute_group;
566 }
567
568 tz->device.groups = groups;
569
570 return 0;
571}
572
573void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
574{
575 if (!tz)
576 return;
577
578 if (tz->num_trips)
579 destroy_trip_attrs(tz);
580
581 kfree(objp: tz->device.groups);
582}
583
584/* sys I/F for cooling device */
585static ssize_t
586cdev_type_show(struct device *dev, struct device_attribute *attr, char *buf)
587{
588 struct thermal_cooling_device *cdev = to_cooling_device(dev);
589
590 return sprintf(buf, fmt: "%s\n", cdev->type);
591}
592
593static ssize_t max_state_show(struct device *dev, struct device_attribute *attr,
594 char *buf)
595{
596 struct thermal_cooling_device *cdev = to_cooling_device(dev);
597
598 return sprintf(buf, fmt: "%ld\n", cdev->max_state);
599}
600
601static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr,
602 char *buf)
603{
604 struct thermal_cooling_device *cdev = to_cooling_device(dev);
605 unsigned long state;
606 int ret;
607
608 ret = cdev->ops->get_cur_state(cdev, &state);
609 if (ret)
610 return ret;
611 return sprintf(buf, fmt: "%ld\n", state);
612}
613
614static ssize_t
615cur_state_store(struct device *dev, struct device_attribute *attr,
616 const char *buf, size_t count)
617{
618 struct thermal_cooling_device *cdev = to_cooling_device(dev);
619 unsigned long state;
620 int result;
621
622 if (sscanf(buf, "%ld\n", &state) != 1)
623 return -EINVAL;
624
625 if ((long)state < 0)
626 return -EINVAL;
627
628 /* Requested state should be less than max_state + 1 */
629 if (state > cdev->max_state)
630 return -EINVAL;
631
632 mutex_lock(&cdev->lock);
633
634 result = cdev->ops->set_cur_state(cdev, state);
635 if (!result)
636 thermal_cooling_device_stats_update(cdev, new_state: state);
637
638 mutex_unlock(lock: &cdev->lock);
639 return result ? result : count;
640}
641
642static struct device_attribute
643dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
644static DEVICE_ATTR_RO(max_state);
645static DEVICE_ATTR_RW(cur_state);
646
647static struct attribute *cooling_device_attrs[] = {
648 &dev_attr_cdev_type.attr,
649 &dev_attr_max_state.attr,
650 &dev_attr_cur_state.attr,
651 NULL,
652};
653
654static const struct attribute_group cooling_device_attr_group = {
655 .attrs = cooling_device_attrs,
656};
657
658static const struct attribute_group *cooling_device_attr_groups[] = {
659 &cooling_device_attr_group,
660 NULL, /* Space allocated for cooling_device_stats_attr_group */
661 NULL,
662};
663
664#ifdef CONFIG_THERMAL_STATISTICS
665struct cooling_dev_stats {
666 spinlock_t lock;
667 unsigned int total_trans;
668 unsigned long state;
669 ktime_t last_time;
670 ktime_t *time_in_state;
671 unsigned int *trans_table;
672};
673
674static void update_time_in_state(struct cooling_dev_stats *stats)
675{
676 ktime_t now = ktime_get(), delta;
677
678 delta = ktime_sub(now, stats->last_time);
679 stats->time_in_state[stats->state] =
680 ktime_add(stats->time_in_state[stats->state], delta);
681 stats->last_time = now;
682}
683
684void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
685 unsigned long new_state)
686{
687 struct cooling_dev_stats *stats = cdev->stats;
688
689 lockdep_assert_held(&cdev->lock);
690
691 if (!stats)
692 return;
693
694 spin_lock(lock: &stats->lock);
695
696 if (stats->state == new_state)
697 goto unlock;
698
699 update_time_in_state(stats);
700 stats->trans_table[stats->state * (cdev->max_state + 1) + new_state]++;
701 stats->state = new_state;
702 stats->total_trans++;
703
704unlock:
705 spin_unlock(lock: &stats->lock);
706}
707
708static ssize_t total_trans_show(struct device *dev,
709 struct device_attribute *attr, char *buf)
710{
711 struct thermal_cooling_device *cdev = to_cooling_device(dev);
712 struct cooling_dev_stats *stats;
713 int ret = 0;
714
715 mutex_lock(&cdev->lock);
716
717 stats = cdev->stats;
718 if (!stats)
719 goto unlock;
720
721 spin_lock(lock: &stats->lock);
722 ret = sprintf(buf, fmt: "%u\n", stats->total_trans);
723 spin_unlock(lock: &stats->lock);
724
725unlock:
726 mutex_unlock(lock: &cdev->lock);
727
728 return ret;
729}
730
731static ssize_t
732time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
733 char *buf)
734{
735 struct thermal_cooling_device *cdev = to_cooling_device(dev);
736 struct cooling_dev_stats *stats;
737 ssize_t len = 0;
738 int i;
739
740 mutex_lock(&cdev->lock);
741
742 stats = cdev->stats;
743 if (!stats)
744 goto unlock;
745
746 spin_lock(lock: &stats->lock);
747
748 update_time_in_state(stats);
749
750 for (i = 0; i <= cdev->max_state; i++) {
751 len += sprintf(buf: buf + len, fmt: "state%u\t%llu\n", i,
752 ktime_to_ms(kt: stats->time_in_state[i]));
753 }
754 spin_unlock(lock: &stats->lock);
755
756unlock:
757 mutex_unlock(lock: &cdev->lock);
758
759 return len;
760}
761
762static ssize_t
763reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
764 size_t count)
765{
766 struct thermal_cooling_device *cdev = to_cooling_device(dev);
767 struct cooling_dev_stats *stats;
768 int i, states;
769
770 mutex_lock(&cdev->lock);
771
772 stats = cdev->stats;
773 if (!stats)
774 goto unlock;
775
776 states = cdev->max_state + 1;
777
778 spin_lock(lock: &stats->lock);
779
780 stats->total_trans = 0;
781 stats->last_time = ktime_get();
782 memset(stats->trans_table, 0,
783 states * states * sizeof(*stats->trans_table));
784
785 for (i = 0; i < states; i++)
786 stats->time_in_state[i] = ktime_set(secs: 0, nsecs: 0);
787
788 spin_unlock(lock: &stats->lock);
789
790unlock:
791 mutex_unlock(lock: &cdev->lock);
792
793 return count;
794}
795
796static ssize_t trans_table_show(struct device *dev,
797 struct device_attribute *attr, char *buf)
798{
799 struct thermal_cooling_device *cdev = to_cooling_device(dev);
800 struct cooling_dev_stats *stats;
801 ssize_t len = 0;
802 int i, j;
803
804 mutex_lock(&cdev->lock);
805
806 stats = cdev->stats;
807 if (!stats) {
808 len = -ENODATA;
809 goto unlock;
810 }
811
812 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: " From : To\n");
813 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: " : ");
814 for (i = 0; i <= cdev->max_state; i++) {
815 if (len >= PAGE_SIZE)
816 break;
817 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: "state%2u ", i);
818 }
819 if (len >= PAGE_SIZE) {
820 len = PAGE_SIZE;
821 goto unlock;
822 }
823
824 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: "\n");
825
826 for (i = 0; i <= cdev->max_state; i++) {
827 if (len >= PAGE_SIZE)
828 break;
829
830 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: "state%2u:", i);
831
832 for (j = 0; j <= cdev->max_state; j++) {
833 if (len >= PAGE_SIZE)
834 break;
835 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: "%8u ",
836 stats->trans_table[i * (cdev->max_state + 1) + j]);
837 }
838 if (len >= PAGE_SIZE)
839 break;
840 len += snprintf(buf: buf + len, PAGE_SIZE - len, fmt: "\n");
841 }
842
843 if (len >= PAGE_SIZE) {
844 pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
845 len = -EFBIG;
846 }
847
848unlock:
849 mutex_unlock(lock: &cdev->lock);
850
851 return len;
852}
853
854static DEVICE_ATTR_RO(total_trans);
855static DEVICE_ATTR_RO(time_in_state_ms);
856static DEVICE_ATTR_WO(reset);
857static DEVICE_ATTR_RO(trans_table);
858
859static struct attribute *cooling_device_stats_attrs[] = {
860 &dev_attr_total_trans.attr,
861 &dev_attr_time_in_state_ms.attr,
862 &dev_attr_reset.attr,
863 &dev_attr_trans_table.attr,
864 NULL
865};
866
867static const struct attribute_group cooling_device_stats_attr_group = {
868 .attrs = cooling_device_stats_attrs,
869 .name = "stats"
870};
871
872static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
873{
874 const struct attribute_group *stats_attr_group = NULL;
875 struct cooling_dev_stats *stats;
876 /* Total number of states is highest state + 1 */
877 unsigned long states = cdev->max_state + 1;
878 int var;
879
880 var = sizeof(*stats);
881 var += sizeof(*stats->time_in_state) * states;
882 var += sizeof(*stats->trans_table) * states * states;
883
884 stats = kzalloc(size: var, GFP_KERNEL);
885 if (!stats)
886 goto out;
887
888 stats->time_in_state = (ktime_t *)(stats + 1);
889 stats->trans_table = (unsigned int *)(stats->time_in_state + states);
890 cdev->stats = stats;
891 stats->last_time = ktime_get();
892
893 spin_lock_init(&stats->lock);
894
895 stats_attr_group = &cooling_device_stats_attr_group;
896
897out:
898 /* Fill the empty slot left in cooling_device_attr_groups */
899 var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
900 cooling_device_attr_groups[var] = stats_attr_group;
901}
902
903static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
904{
905 kfree(objp: cdev->stats);
906 cdev->stats = NULL;
907}
908
909#else
910
911static inline void
912cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
913static inline void
914cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
915
916#endif /* CONFIG_THERMAL_STATISTICS */
917
918void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
919{
920 cooling_device_stats_setup(cdev);
921 cdev->device.groups = cooling_device_attr_groups;
922}
923
924void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
925{
926 cooling_device_stats_destroy(cdev);
927}
928
929void thermal_cooling_device_stats_reinit(struct thermal_cooling_device *cdev)
930{
931 lockdep_assert_held(&cdev->lock);
932
933 cooling_device_stats_destroy(cdev);
934 cooling_device_stats_setup(cdev);
935}
936
937/* these helper will be used only at the time of bindig */
938ssize_t
939trip_point_show(struct device *dev, struct device_attribute *attr, char *buf)
940{
941 struct thermal_instance *instance;
942
943 instance =
944 container_of(attr, struct thermal_instance, attr);
945
946 return sprintf(buf, fmt: "%d\n",
947 thermal_zone_trip_id(tz: instance->tz, trip: instance->trip));
948}
949
950ssize_t
951weight_show(struct device *dev, struct device_attribute *attr, char *buf)
952{
953 struct thermal_instance *instance;
954
955 instance = container_of(attr, struct thermal_instance, weight_attr);
956
957 return sprintf(buf, fmt: "%d\n", instance->weight);
958}
959
960ssize_t weight_store(struct device *dev, struct device_attribute *attr,
961 const char *buf, size_t count)
962{
963 struct thermal_instance *instance;
964 int ret, weight;
965
966 ret = kstrtoint(s: buf, base: 0, res: &weight);
967 if (ret)
968 return ret;
969
970 instance = container_of(attr, struct thermal_instance, weight_attr);
971 instance->weight = weight;
972
973 return count;
974}
975

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