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 
26 static ssize_t
27 type_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, "%s\n", tz->type);
32 }
33 
34 static ssize_t
35 temp_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, &temperature);
41 
42 	if (ret)
43 		return ret;
44 
45 	return sprintf(buf, "%d\n", temperature);
46 }
47 
48 static ssize_t
49 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
50 {
51 	struct thermal_zone_device *tz = to_thermal_zone(dev);
52 	enum thermal_device_mode mode;
53 	int result;
54 
55 	if (!tz->ops->get_mode)
56 		return -EPERM;
57 
58 	result = tz->ops->get_mode(tz, &mode);
59 	if (result)
60 		return result;
61 
62 	return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
63 		       : "disabled");
64 }
65 
66 static ssize_t
67 mode_store(struct device *dev, struct device_attribute *attr,
68 	   const char *buf, size_t count)
69 {
70 	struct thermal_zone_device *tz = to_thermal_zone(dev);
71 	int result;
72 
73 	if (!tz->ops->set_mode)
74 		return -EPERM;
75 
76 	if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
77 		result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
78 	else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
79 		result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
80 	else
81 		result = -EINVAL;
82 
83 	if (result)
84 		return result;
85 
86 	return count;
87 }
88 
89 static ssize_t
90 trip_point_type_show(struct device *dev, struct device_attribute *attr,
91 		     char *buf)
92 {
93 	struct thermal_zone_device *tz = to_thermal_zone(dev);
94 	enum thermal_trip_type type;
95 	int trip, result;
96 
97 	if (!tz->ops->get_trip_type)
98 		return -EPERM;
99 
100 	if (sscanf(attr->attr.name, "trip_point_%d_type", &trip) != 1)
101 		return -EINVAL;
102 
103 	result = tz->ops->get_trip_type(tz, trip, &type);
104 	if (result)
105 		return result;
106 
107 	switch (type) {
108 	case THERMAL_TRIP_CRITICAL:
109 		return sprintf(buf, "critical\n");
110 	case THERMAL_TRIP_HOT:
111 		return sprintf(buf, "hot\n");
112 	case THERMAL_TRIP_PASSIVE:
113 		return sprintf(buf, "passive\n");
114 	case THERMAL_TRIP_ACTIVE:
115 		return sprintf(buf, "active\n");
116 	default:
117 		return sprintf(buf, "unknown\n");
118 	}
119 }
120 
121 static ssize_t
122 trip_point_temp_store(struct device *dev, struct device_attribute *attr,
123 		      const char *buf, size_t count)
124 {
125 	struct thermal_zone_device *tz = to_thermal_zone(dev);
126 	int trip, ret;
127 	int temperature;
128 
129 	if (!tz->ops->set_trip_temp)
130 		return -EPERM;
131 
132 	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
133 		return -EINVAL;
134 
135 	if (kstrtoint(buf, 10, &temperature))
136 		return -EINVAL;
137 
138 	ret = tz->ops->set_trip_temp(tz, trip, temperature);
139 	if (ret)
140 		return ret;
141 
142 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
143 
144 	return count;
145 }
146 
147 static ssize_t
148 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
149 		     char *buf)
150 {
151 	struct thermal_zone_device *tz = to_thermal_zone(dev);
152 	int trip, ret;
153 	int temperature;
154 
155 	if (!tz->ops->get_trip_temp)
156 		return -EPERM;
157 
158 	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
159 		return -EINVAL;
160 
161 	ret = tz->ops->get_trip_temp(tz, trip, &temperature);
162 
163 	if (ret)
164 		return ret;
165 
166 	return sprintf(buf, "%d\n", temperature);
167 }
168 
169 static ssize_t
170 trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
171 		      const char *buf, size_t count)
172 {
173 	struct thermal_zone_device *tz = to_thermal_zone(dev);
174 	int trip, ret;
175 	int temperature;
176 
177 	if (!tz->ops->set_trip_hyst)
178 		return -EPERM;
179 
180 	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
181 		return -EINVAL;
182 
183 	if (kstrtoint(buf, 10, &temperature))
184 		return -EINVAL;
185 
186 	/*
187 	 * We are not doing any check on the 'temperature' value
188 	 * here. The driver implementing 'set_trip_hyst' has to
189 	 * take care of this.
190 	 */
191 	ret = tz->ops->set_trip_hyst(tz, trip, temperature);
192 
193 	if (!ret)
194 		thermal_zone_set_trips(tz);
195 
196 	return ret ? ret : count;
197 }
198 
199 static ssize_t
200 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
201 		     char *buf)
202 {
203 	struct thermal_zone_device *tz = to_thermal_zone(dev);
204 	int trip, ret;
205 	int temperature;
206 
207 	if (!tz->ops->get_trip_hyst)
208 		return -EPERM;
209 
210 	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
211 		return -EINVAL;
212 
213 	ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
214 
215 	return ret ? ret : sprintf(buf, "%d\n", temperature);
216 }
217 
218 static ssize_t
219 passive_store(struct device *dev, struct device_attribute *attr,
220 	      const char *buf, size_t count)
221 {
222 	struct thermal_zone_device *tz = to_thermal_zone(dev);
223 	int state;
224 
225 	if (sscanf(buf, "%d\n", &state) != 1)
226 		return -EINVAL;
227 
228 	/* sanity check: values below 1000 millicelcius don't make sense
229 	 * and can cause the system to go into a thermal heart attack
230 	 */
231 	if (state && state < 1000)
232 		return -EINVAL;
233 
234 	if (state && !tz->forced_passive) {
235 		if (!tz->passive_delay)
236 			tz->passive_delay = 1000;
237 		thermal_zone_device_rebind_exception(tz, "Processor",
238 						     sizeof("Processor"));
239 	} else if (!state && tz->forced_passive) {
240 		tz->passive_delay = 0;
241 		thermal_zone_device_unbind_exception(tz, "Processor",
242 						     sizeof("Processor"));
243 	}
244 
245 	tz->forced_passive = state;
246 
247 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
248 
249 	return count;
250 }
251 
252 static ssize_t
253 passive_show(struct device *dev, struct device_attribute *attr,
254 	     char *buf)
255 {
256 	struct thermal_zone_device *tz = to_thermal_zone(dev);
257 
258 	return sprintf(buf, "%d\n", tz->forced_passive);
259 }
260 
261 static ssize_t
262 policy_store(struct device *dev, struct device_attribute *attr,
263 	     const char *buf, size_t count)
264 {
265 	struct thermal_zone_device *tz = to_thermal_zone(dev);
266 	char name[THERMAL_NAME_LENGTH];
267 	int ret;
268 
269 	snprintf(name, sizeof(name), "%s", buf);
270 
271 	ret = thermal_zone_device_set_policy(tz, name);
272 	if (!ret)
273 		ret = count;
274 
275 	return ret;
276 }
277 
278 static ssize_t
279 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
280 {
281 	struct thermal_zone_device *tz = to_thermal_zone(dev);
282 
283 	return sprintf(buf, "%s\n", tz->governor->name);
284 }
285 
286 static ssize_t
287 available_policies_show(struct device *dev, struct device_attribute *devattr,
288 			char *buf)
289 {
290 	return thermal_build_list_of_policies(buf);
291 }
292 
293 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
294 static ssize_t
295 emul_temp_store(struct device *dev, struct device_attribute *attr,
296 		const char *buf, size_t count)
297 {
298 	struct thermal_zone_device *tz = to_thermal_zone(dev);
299 	int ret = 0;
300 	int temperature;
301 
302 	if (kstrtoint(buf, 10, &temperature))
303 		return -EINVAL;
304 
305 	if (!tz->ops->set_emul_temp) {
306 		mutex_lock(&tz->lock);
307 		tz->emul_temperature = temperature;
308 		mutex_unlock(&tz->lock);
309 	} else {
310 		ret = tz->ops->set_emul_temp(tz, temperature);
311 	}
312 
313 	if (!ret)
314 		thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
315 
316 	return ret ? ret : count;
317 }
318 static DEVICE_ATTR_WO(emul_temp);
319 #endif
320 
321 static ssize_t
322 sustainable_power_show(struct device *dev, struct device_attribute *devattr,
323 		       char *buf)
324 {
325 	struct thermal_zone_device *tz = to_thermal_zone(dev);
326 
327 	if (tz->tzp)
328 		return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
329 	else
330 		return -EIO;
331 }
332 
333 static ssize_t
334 sustainable_power_store(struct device *dev, struct device_attribute *devattr,
335 			const char *buf, size_t count)
336 {
337 	struct thermal_zone_device *tz = to_thermal_zone(dev);
338 	u32 sustainable_power;
339 
340 	if (!tz->tzp)
341 		return -EIO;
342 
343 	if (kstrtou32(buf, 10, &sustainable_power))
344 		return -EINVAL;
345 
346 	tz->tzp->sustainable_power = sustainable_power;
347 
348 	return count;
349 }
350 
351 #define create_s32_tzp_attr(name)					\
352 	static ssize_t							\
353 	name##_show(struct device *dev, struct device_attribute *devattr, \
354 		char *buf)						\
355 	{								\
356 	struct thermal_zone_device *tz = to_thermal_zone(dev);		\
357 									\
358 	if (tz->tzp)							\
359 		return sprintf(buf, "%d\n", tz->tzp->name);		\
360 	else								\
361 		return -EIO;						\
362 	}								\
363 									\
364 	static ssize_t							\
365 	name##_store(struct device *dev, struct device_attribute *devattr, \
366 		const char *buf, size_t count)				\
367 	{								\
368 		struct thermal_zone_device *tz = to_thermal_zone(dev);	\
369 		s32 value;						\
370 									\
371 		if (!tz->tzp)						\
372 			return -EIO;					\
373 									\
374 		if (kstrtos32(buf, 10, &value))				\
375 			return -EINVAL;					\
376 									\
377 		tz->tzp->name = value;					\
378 									\
379 		return count;						\
380 	}								\
381 	static DEVICE_ATTR_RW(name)
382 
383 create_s32_tzp_attr(k_po);
384 create_s32_tzp_attr(k_pu);
385 create_s32_tzp_attr(k_i);
386 create_s32_tzp_attr(k_d);
387 create_s32_tzp_attr(integral_cutoff);
388 create_s32_tzp_attr(slope);
389 create_s32_tzp_attr(offset);
390 #undef create_s32_tzp_attr
391 
392 /*
393  * These are thermal zone device attributes that will always be present.
394  * All the attributes created for tzp (create_s32_tzp_attr) also are always
395  * present on the sysfs interface.
396  */
397 static DEVICE_ATTR_RO(type);
398 static DEVICE_ATTR_RO(temp);
399 static DEVICE_ATTR_RW(policy);
400 static DEVICE_ATTR_RO(available_policies);
401 static DEVICE_ATTR_RW(sustainable_power);
402 
403 /* These thermal zone device attributes are created based on conditions */
404 static DEVICE_ATTR_RW(mode);
405 static DEVICE_ATTR_RW(passive);
406 
407 /* These attributes are unconditionally added to a thermal zone */
408 static struct attribute *thermal_zone_dev_attrs[] = {
409 	&dev_attr_type.attr,
410 	&dev_attr_temp.attr,
411 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
412 	&dev_attr_emul_temp.attr,
413 #endif
414 	&dev_attr_policy.attr,
415 	&dev_attr_available_policies.attr,
416 	&dev_attr_sustainable_power.attr,
417 	&dev_attr_k_po.attr,
418 	&dev_attr_k_pu.attr,
419 	&dev_attr_k_i.attr,
420 	&dev_attr_k_d.attr,
421 	&dev_attr_integral_cutoff.attr,
422 	&dev_attr_slope.attr,
423 	&dev_attr_offset.attr,
424 	NULL,
425 };
426 
427 static struct attribute_group thermal_zone_attribute_group = {
428 	.attrs = thermal_zone_dev_attrs,
429 };
430 
431 /* We expose mode only if .get_mode is present */
432 static struct attribute *thermal_zone_mode_attrs[] = {
433 	&dev_attr_mode.attr,
434 	NULL,
435 };
436 
437 static umode_t thermal_zone_mode_is_visible(struct kobject *kobj,
438 					    struct attribute *attr,
439 					    int attrno)
440 {
441 	struct device *dev = container_of(kobj, struct device, kobj);
442 	struct thermal_zone_device *tz;
443 
444 	tz = container_of(dev, struct thermal_zone_device, device);
445 
446 	if (tz->ops->get_mode)
447 		return attr->mode;
448 
449 	return 0;
450 }
451 
452 static struct attribute_group thermal_zone_mode_attribute_group = {
453 	.attrs = thermal_zone_mode_attrs,
454 	.is_visible = thermal_zone_mode_is_visible,
455 };
456 
457 /* We expose passive only if passive trips are present */
458 static struct attribute *thermal_zone_passive_attrs[] = {
459 	&dev_attr_passive.attr,
460 	NULL,
461 };
462 
463 static umode_t thermal_zone_passive_is_visible(struct kobject *kobj,
464 					       struct attribute *attr,
465 					       int attrno)
466 {
467 	struct device *dev = container_of(kobj, struct device, kobj);
468 	struct thermal_zone_device *tz;
469 	enum thermal_trip_type trip_type;
470 	int count, passive = 0;
471 
472 	tz = container_of(dev, struct thermal_zone_device, device);
473 
474 	for (count = 0; count < tz->trips && !passive; count++) {
475 		tz->ops->get_trip_type(tz, count, &trip_type);
476 
477 		if (trip_type == THERMAL_TRIP_PASSIVE)
478 			passive = 1;
479 	}
480 
481 	if (!passive)
482 		return attr->mode;
483 
484 	return 0;
485 }
486 
487 static struct attribute_group thermal_zone_passive_attribute_group = {
488 	.attrs = thermal_zone_passive_attrs,
489 	.is_visible = thermal_zone_passive_is_visible,
490 };
491 
492 static const struct attribute_group *thermal_zone_attribute_groups[] = {
493 	&thermal_zone_attribute_group,
494 	&thermal_zone_mode_attribute_group,
495 	&thermal_zone_passive_attribute_group,
496 	/* This is not NULL terminated as we create the group dynamically */
497 };
498 
499 /**
500  * create_trip_attrs() - create attributes for trip points
501  * @tz:		the thermal zone device
502  * @mask:	Writeable trip point bitmap.
503  *
504  * helper function to instantiate sysfs entries for every trip
505  * point and its properties of a struct thermal_zone_device.
506  *
507  * Return: 0 on success, the proper error value otherwise.
508  */
509 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
510 {
511 	struct attribute **attrs;
512 	int indx;
513 
514 	/* This function works only for zones with at least one trip */
515 	if (tz->trips <= 0)
516 		return -EINVAL;
517 
518 	tz->trip_type_attrs = kcalloc(tz->trips, sizeof(*tz->trip_type_attrs),
519 				      GFP_KERNEL);
520 	if (!tz->trip_type_attrs)
521 		return -ENOMEM;
522 
523 	tz->trip_temp_attrs = kcalloc(tz->trips, sizeof(*tz->trip_temp_attrs),
524 				      GFP_KERNEL);
525 	if (!tz->trip_temp_attrs) {
526 		kfree(tz->trip_type_attrs);
527 		return -ENOMEM;
528 	}
529 
530 	if (tz->ops->get_trip_hyst) {
531 		tz->trip_hyst_attrs = kcalloc(tz->trips,
532 					      sizeof(*tz->trip_hyst_attrs),
533 					      GFP_KERNEL);
534 		if (!tz->trip_hyst_attrs) {
535 			kfree(tz->trip_type_attrs);
536 			kfree(tz->trip_temp_attrs);
537 			return -ENOMEM;
538 		}
539 	}
540 
541 	attrs = kcalloc(tz->trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
542 	if (!attrs) {
543 		kfree(tz->trip_type_attrs);
544 		kfree(tz->trip_temp_attrs);
545 		if (tz->ops->get_trip_hyst)
546 			kfree(tz->trip_hyst_attrs);
547 		return -ENOMEM;
548 	}
549 
550 	for (indx = 0; indx < tz->trips; indx++) {
551 		/* create trip type attribute */
552 		snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
553 			 "trip_point_%d_type", indx);
554 
555 		sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
556 		tz->trip_type_attrs[indx].attr.attr.name =
557 						tz->trip_type_attrs[indx].name;
558 		tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
559 		tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
560 		attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
561 
562 		/* create trip temp attribute */
563 		snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
564 			 "trip_point_%d_temp", indx);
565 
566 		sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
567 		tz->trip_temp_attrs[indx].attr.attr.name =
568 						tz->trip_temp_attrs[indx].name;
569 		tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
570 		tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
571 		if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
572 		    mask & (1 << indx)) {
573 			tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
574 			tz->trip_temp_attrs[indx].attr.store =
575 							trip_point_temp_store;
576 		}
577 		attrs[indx + tz->trips] = &tz->trip_temp_attrs[indx].attr.attr;
578 
579 		/* create Optional trip hyst attribute */
580 		if (!tz->ops->get_trip_hyst)
581 			continue;
582 		snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
583 			 "trip_point_%d_hyst", indx);
584 
585 		sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
586 		tz->trip_hyst_attrs[indx].attr.attr.name =
587 					tz->trip_hyst_attrs[indx].name;
588 		tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
589 		tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
590 		if (tz->ops->set_trip_hyst) {
591 			tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
592 			tz->trip_hyst_attrs[indx].attr.store =
593 					trip_point_hyst_store;
594 		}
595 		attrs[indx + tz->trips * 2] =
596 					&tz->trip_hyst_attrs[indx].attr.attr;
597 	}
598 	attrs[tz->trips * 3] = NULL;
599 
600 	tz->trips_attribute_group.attrs = attrs;
601 
602 	return 0;
603 }
604 
605 /**
606  * destroy_trip_attrs() - destroy attributes for trip points
607  * @tz:		the thermal zone device
608  *
609  * helper function to free resources allocated by create_trip_attrs()
610  */
611 static void destroy_trip_attrs(struct thermal_zone_device *tz)
612 {
613 	if (!tz)
614 		return;
615 
616 	kfree(tz->trip_type_attrs);
617 	kfree(tz->trip_temp_attrs);
618 	if (tz->ops->get_trip_hyst)
619 		kfree(tz->trip_hyst_attrs);
620 	kfree(tz->trips_attribute_group.attrs);
621 }
622 
623 int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
624 				      int mask)
625 {
626 	const struct attribute_group **groups;
627 	int i, size, result;
628 
629 	/* we need one extra for trips and the NULL to terminate the array */
630 	size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
631 	/* This also takes care of API requirement to be NULL terminated */
632 	groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
633 	if (!groups)
634 		return -ENOMEM;
635 
636 	for (i = 0; i < size - 2; i++)
637 		groups[i] = thermal_zone_attribute_groups[i];
638 
639 	if (tz->trips) {
640 		result = create_trip_attrs(tz, mask);
641 		if (result) {
642 			kfree(groups);
643 
644 			return result;
645 		}
646 
647 		groups[size - 2] = &tz->trips_attribute_group;
648 	}
649 
650 	tz->device.groups = groups;
651 
652 	return 0;
653 }
654 
655 void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
656 {
657 	if (!tz)
658 		return;
659 
660 	if (tz->trips)
661 		destroy_trip_attrs(tz);
662 
663 	kfree(tz->device.groups);
664 }
665 
666 /* sys I/F for cooling device */
667 static ssize_t
668 cdev_type_show(struct device *dev, struct device_attribute *attr, char *buf)
669 {
670 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
671 
672 	return sprintf(buf, "%s\n", cdev->type);
673 }
674 
675 static ssize_t max_state_show(struct device *dev, struct device_attribute *attr,
676 			      char *buf)
677 {
678 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
679 	unsigned long state;
680 	int ret;
681 
682 	ret = cdev->ops->get_max_state(cdev, &state);
683 	if (ret)
684 		return ret;
685 	return sprintf(buf, "%ld\n", state);
686 }
687 
688 static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr,
689 			      char *buf)
690 {
691 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
692 	unsigned long state;
693 	int ret;
694 
695 	ret = cdev->ops->get_cur_state(cdev, &state);
696 	if (ret)
697 		return ret;
698 	return sprintf(buf, "%ld\n", state);
699 }
700 
701 static ssize_t
702 cur_state_store(struct device *dev, struct device_attribute *attr,
703 		const char *buf, size_t count)
704 {
705 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
706 	unsigned long state;
707 	int result;
708 
709 	if (sscanf(buf, "%ld\n", &state) != 1)
710 		return -EINVAL;
711 
712 	if ((long)state < 0)
713 		return -EINVAL;
714 
715 	mutex_lock(&cdev->lock);
716 
717 	result = cdev->ops->set_cur_state(cdev, state);
718 	if (!result)
719 		thermal_cooling_device_stats_update(cdev, state);
720 
721 	mutex_unlock(&cdev->lock);
722 	return result ? result : count;
723 }
724 
725 static struct device_attribute
726 dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
727 static DEVICE_ATTR_RO(max_state);
728 static DEVICE_ATTR_RW(cur_state);
729 
730 static struct attribute *cooling_device_attrs[] = {
731 	&dev_attr_cdev_type.attr,
732 	&dev_attr_max_state.attr,
733 	&dev_attr_cur_state.attr,
734 	NULL,
735 };
736 
737 static const struct attribute_group cooling_device_attr_group = {
738 	.attrs = cooling_device_attrs,
739 };
740 
741 static const struct attribute_group *cooling_device_attr_groups[] = {
742 	&cooling_device_attr_group,
743 	NULL, /* Space allocated for cooling_device_stats_attr_group */
744 	NULL,
745 };
746 
747 #ifdef CONFIG_THERMAL_STATISTICS
748 struct cooling_dev_stats {
749 	spinlock_t lock;
750 	unsigned int total_trans;
751 	unsigned long state;
752 	unsigned long max_states;
753 	ktime_t last_time;
754 	ktime_t *time_in_state;
755 	unsigned int *trans_table;
756 };
757 
758 static void update_time_in_state(struct cooling_dev_stats *stats)
759 {
760 	ktime_t now = ktime_get(), delta;
761 
762 	delta = ktime_sub(now, stats->last_time);
763 	stats->time_in_state[stats->state] =
764 		ktime_add(stats->time_in_state[stats->state], delta);
765 	stats->last_time = now;
766 }
767 
768 void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
769 					 unsigned long new_state)
770 {
771 	struct cooling_dev_stats *stats = cdev->stats;
772 
773 	spin_lock(&stats->lock);
774 
775 	if (stats->state == new_state)
776 		goto unlock;
777 
778 	update_time_in_state(stats);
779 	stats->trans_table[stats->state * stats->max_states + new_state]++;
780 	stats->state = new_state;
781 	stats->total_trans++;
782 
783 unlock:
784 	spin_unlock(&stats->lock);
785 }
786 
787 static ssize_t total_trans_show(struct device *dev,
788 				struct device_attribute *attr, char *buf)
789 {
790 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
791 	struct cooling_dev_stats *stats = cdev->stats;
792 	int ret;
793 
794 	spin_lock(&stats->lock);
795 	ret = sprintf(buf, "%u\n", stats->total_trans);
796 	spin_unlock(&stats->lock);
797 
798 	return ret;
799 }
800 
801 static ssize_t
802 time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
803 		      char *buf)
804 {
805 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
806 	struct cooling_dev_stats *stats = cdev->stats;
807 	ssize_t len = 0;
808 	int i;
809 
810 	spin_lock(&stats->lock);
811 	update_time_in_state(stats);
812 
813 	for (i = 0; i < stats->max_states; i++) {
814 		len += sprintf(buf + len, "state%u\t%llu\n", i,
815 			       ktime_to_ms(stats->time_in_state[i]));
816 	}
817 	spin_unlock(&stats->lock);
818 
819 	return len;
820 }
821 
822 static ssize_t
823 reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
824 	    size_t count)
825 {
826 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
827 	struct cooling_dev_stats *stats = cdev->stats;
828 	int i, states = stats->max_states;
829 
830 	spin_lock(&stats->lock);
831 
832 	stats->total_trans = 0;
833 	stats->last_time = ktime_get();
834 	memset(stats->trans_table, 0,
835 	       states * states * sizeof(*stats->trans_table));
836 
837 	for (i = 0; i < stats->max_states; i++)
838 		stats->time_in_state[i] = ktime_set(0, 0);
839 
840 	spin_unlock(&stats->lock);
841 
842 	return count;
843 }
844 
845 static ssize_t trans_table_show(struct device *dev,
846 				struct device_attribute *attr, char *buf)
847 {
848 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
849 	struct cooling_dev_stats *stats = cdev->stats;
850 	ssize_t len = 0;
851 	int i, j;
852 
853 	len += snprintf(buf + len, PAGE_SIZE - len, " From  :    To\n");
854 	len += snprintf(buf + len, PAGE_SIZE - len, "       : ");
855 	for (i = 0; i < stats->max_states; i++) {
856 		if (len >= PAGE_SIZE)
857 			break;
858 		len += snprintf(buf + len, PAGE_SIZE - len, "state%2u  ", i);
859 	}
860 	if (len >= PAGE_SIZE)
861 		return PAGE_SIZE;
862 
863 	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
864 
865 	for (i = 0; i < stats->max_states; i++) {
866 		if (len >= PAGE_SIZE)
867 			break;
868 
869 		len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i);
870 
871 		for (j = 0; j < stats->max_states; j++) {
872 			if (len >= PAGE_SIZE)
873 				break;
874 			len += snprintf(buf + len, PAGE_SIZE - len, "%8u ",
875 				stats->trans_table[i * stats->max_states + j]);
876 		}
877 		if (len >= PAGE_SIZE)
878 			break;
879 		len += snprintf(buf + len, PAGE_SIZE - len, "\n");
880 	}
881 
882 	if (len >= PAGE_SIZE) {
883 		pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
884 		return -EFBIG;
885 	}
886 	return len;
887 }
888 
889 static DEVICE_ATTR_RO(total_trans);
890 static DEVICE_ATTR_RO(time_in_state_ms);
891 static DEVICE_ATTR_WO(reset);
892 static DEVICE_ATTR_RO(trans_table);
893 
894 static struct attribute *cooling_device_stats_attrs[] = {
895 	&dev_attr_total_trans.attr,
896 	&dev_attr_time_in_state_ms.attr,
897 	&dev_attr_reset.attr,
898 	&dev_attr_trans_table.attr,
899 	NULL
900 };
901 
902 static const struct attribute_group cooling_device_stats_attr_group = {
903 	.attrs = cooling_device_stats_attrs,
904 	.name = "stats"
905 };
906 
907 static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
908 {
909 	struct cooling_dev_stats *stats;
910 	unsigned long states;
911 	int var;
912 
913 	if (cdev->ops->get_max_state(cdev, &states))
914 		return;
915 
916 	states++; /* Total number of states is highest state + 1 */
917 
918 	var = sizeof(*stats);
919 	var += sizeof(*stats->time_in_state) * states;
920 	var += sizeof(*stats->trans_table) * states * states;
921 
922 	stats = kzalloc(var, GFP_KERNEL);
923 	if (!stats)
924 		return;
925 
926 	stats->time_in_state = (ktime_t *)(stats + 1);
927 	stats->trans_table = (unsigned int *)(stats->time_in_state + states);
928 	cdev->stats = stats;
929 	stats->last_time = ktime_get();
930 	stats->max_states = states;
931 
932 	spin_lock_init(&stats->lock);
933 
934 	/* Fill the empty slot left in cooling_device_attr_groups */
935 	var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
936 	cooling_device_attr_groups[var] = &cooling_device_stats_attr_group;
937 }
938 
939 static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
940 {
941 	kfree(cdev->stats);
942 	cdev->stats = NULL;
943 }
944 
945 #else
946 
947 static inline void
948 cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
949 static inline void
950 cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
951 
952 #endif /* CONFIG_THERMAL_STATISTICS */
953 
954 void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
955 {
956 	cooling_device_stats_setup(cdev);
957 	cdev->device.groups = cooling_device_attr_groups;
958 }
959 
960 void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
961 {
962 	cooling_device_stats_destroy(cdev);
963 }
964 
965 /* these helper will be used only at the time of bindig */
966 ssize_t
967 trip_point_show(struct device *dev, struct device_attribute *attr, char *buf)
968 {
969 	struct thermal_instance *instance;
970 
971 	instance =
972 	    container_of(attr, struct thermal_instance, attr);
973 
974 	if (instance->trip == THERMAL_TRIPS_NONE)
975 		return sprintf(buf, "-1\n");
976 	else
977 		return sprintf(buf, "%d\n", instance->trip);
978 }
979 
980 ssize_t
981 weight_show(struct device *dev, struct device_attribute *attr, char *buf)
982 {
983 	struct thermal_instance *instance;
984 
985 	instance = container_of(attr, struct thermal_instance, weight_attr);
986 
987 	return sprintf(buf, "%d\n", instance->weight);
988 }
989 
990 ssize_t weight_store(struct device *dev, struct device_attribute *attr,
991 		     const char *buf, size_t count)
992 {
993 	struct thermal_instance *instance;
994 	int ret, weight;
995 
996 	ret = kstrtoint(buf, 0, &weight);
997 	if (ret)
998 		return ret;
999 
1000 	instance = container_of(attr, struct thermal_instance, weight_attr);
1001 	instance->weight = weight;
1002 
1003 	return count;
1004 }
1005