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

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