1 /*
2  *  thermal.c - sysfs interface of thermal devices
3  *
4  *  Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
5  *
6  *  Highly based on original thermal_core.c
7  *  Copyright (C) 2008 Intel Corp
8  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
9  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
10  *
11  *  This program is free software; you can redistribute it and/or modify
12  *  it under the terms of the GNU General Public License as published by
13  *  the Free Software Foundation; version 2 of the License.
14  */
15 
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 
18 #include <linux/sysfs.h>
19 #include <linux/device.h>
20 #include <linux/err.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 
24 #include "thermal_core.h"
25 
26 /* sys I/F for thermal zone */
27 
28 static ssize_t
29 type_show(struct device *dev, struct device_attribute *attr, char *buf)
30 {
31 	struct thermal_zone_device *tz = to_thermal_zone(dev);
32 
33 	return sprintf(buf, "%s\n", tz->type);
34 }
35 
36 static ssize_t
37 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
38 {
39 	struct thermal_zone_device *tz = to_thermal_zone(dev);
40 	int temperature, ret;
41 
42 	ret = thermal_zone_get_temp(tz, &temperature);
43 
44 	if (ret)
45 		return ret;
46 
47 	return sprintf(buf, "%d\n", temperature);
48 }
49 
50 static ssize_t
51 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
52 {
53 	struct thermal_zone_device *tz = to_thermal_zone(dev);
54 	enum thermal_device_mode mode;
55 	int result;
56 
57 	if (!tz->ops->get_mode)
58 		return -EPERM;
59 
60 	result = tz->ops->get_mode(tz, &mode);
61 	if (result)
62 		return result;
63 
64 	return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
65 		       : "disabled");
66 }
67 
68 static ssize_t
69 mode_store(struct device *dev, struct device_attribute *attr,
70 	   const char *buf, size_t count)
71 {
72 	struct thermal_zone_device *tz = to_thermal_zone(dev);
73 	int result;
74 
75 	if (!tz->ops->set_mode)
76 		return -EPERM;
77 
78 	if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
79 		result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
80 	else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
81 		result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
82 	else
83 		result = -EINVAL;
84 
85 	if (result)
86 		return result;
87 
88 	return count;
89 }
90 
91 static ssize_t
92 trip_point_type_show(struct device *dev, struct device_attribute *attr,
93 		     char *buf)
94 {
95 	struct thermal_zone_device *tz = to_thermal_zone(dev);
96 	enum thermal_trip_type type;
97 	int trip, result;
98 
99 	if (!tz->ops->get_trip_type)
100 		return -EPERM;
101 
102 	if (sscanf(attr->attr.name, "trip_point_%d_type", &trip) != 1)
103 		return -EINVAL;
104 
105 	result = tz->ops->get_trip_type(tz, trip, &type);
106 	if (result)
107 		return result;
108 
109 	switch (type) {
110 	case THERMAL_TRIP_CRITICAL:
111 		return sprintf(buf, "critical\n");
112 	case THERMAL_TRIP_HOT:
113 		return sprintf(buf, "hot\n");
114 	case THERMAL_TRIP_PASSIVE:
115 		return sprintf(buf, "passive\n");
116 	case THERMAL_TRIP_ACTIVE:
117 		return sprintf(buf, "active\n");
118 	default:
119 		return sprintf(buf, "unknown\n");
120 	}
121 }
122 
123 static ssize_t
124 trip_point_temp_store(struct device *dev, struct device_attribute *attr,
125 		      const char *buf, size_t count)
126 {
127 	struct thermal_zone_device *tz = to_thermal_zone(dev);
128 	int trip, ret;
129 	int temperature;
130 
131 	if (!tz->ops->set_trip_temp)
132 		return -EPERM;
133 
134 	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
135 		return -EINVAL;
136 
137 	if (kstrtoint(buf, 10, &temperature))
138 		return -EINVAL;
139 
140 	ret = tz->ops->set_trip_temp(tz, trip, temperature);
141 	if (ret)
142 		return ret;
143 
144 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
145 
146 	return count;
147 }
148 
149 static ssize_t
150 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
151 		     char *buf)
152 {
153 	struct thermal_zone_device *tz = to_thermal_zone(dev);
154 	int trip, ret;
155 	int temperature;
156 
157 	if (!tz->ops->get_trip_temp)
158 		return -EPERM;
159 
160 	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
161 		return -EINVAL;
162 
163 	ret = tz->ops->get_trip_temp(tz, trip, &temperature);
164 
165 	if (ret)
166 		return ret;
167 
168 	return sprintf(buf, "%d\n", temperature);
169 }
170 
171 static ssize_t
172 trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
173 		      const char *buf, size_t count)
174 {
175 	struct thermal_zone_device *tz = to_thermal_zone(dev);
176 	int trip, ret;
177 	int temperature;
178 
179 	if (!tz->ops->set_trip_hyst)
180 		return -EPERM;
181 
182 	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
183 		return -EINVAL;
184 
185 	if (kstrtoint(buf, 10, &temperature))
186 		return -EINVAL;
187 
188 	/*
189 	 * We are not doing any check on the 'temperature' value
190 	 * here. The driver implementing 'set_trip_hyst' has to
191 	 * take care of this.
192 	 */
193 	ret = tz->ops->set_trip_hyst(tz, trip, temperature);
194 
195 	if (!ret)
196 		thermal_zone_set_trips(tz);
197 
198 	return ret ? ret : count;
199 }
200 
201 static ssize_t
202 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
203 		     char *buf)
204 {
205 	struct thermal_zone_device *tz = to_thermal_zone(dev);
206 	int trip, ret;
207 	int temperature;
208 
209 	if (!tz->ops->get_trip_hyst)
210 		return -EPERM;
211 
212 	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
213 		return -EINVAL;
214 
215 	ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
216 
217 	return ret ? ret : sprintf(buf, "%d\n", temperature);
218 }
219 
220 static ssize_t
221 passive_store(struct device *dev, struct device_attribute *attr,
222 	      const char *buf, size_t count)
223 {
224 	struct thermal_zone_device *tz = to_thermal_zone(dev);
225 	int state;
226 
227 	if (sscanf(buf, "%d\n", &state) != 1)
228 		return -EINVAL;
229 
230 	/* sanity check: values below 1000 millicelcius don't make sense
231 	 * and can cause the system to go into a thermal heart attack
232 	 */
233 	if (state && state < 1000)
234 		return -EINVAL;
235 
236 	if (state && !tz->forced_passive) {
237 		if (!tz->passive_delay)
238 			tz->passive_delay = 1000;
239 		thermal_zone_device_rebind_exception(tz, "Processor",
240 						     sizeof("Processor"));
241 	} else if (!state && tz->forced_passive) {
242 		tz->passive_delay = 0;
243 		thermal_zone_device_unbind_exception(tz, "Processor",
244 						     sizeof("Processor"));
245 	}
246 
247 	tz->forced_passive = state;
248 
249 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
250 
251 	return count;
252 }
253 
254 static ssize_t
255 passive_show(struct device *dev, struct device_attribute *attr,
256 	     char *buf)
257 {
258 	struct thermal_zone_device *tz = to_thermal_zone(dev);
259 
260 	return sprintf(buf, "%d\n", tz->forced_passive);
261 }
262 
263 static ssize_t
264 policy_store(struct device *dev, struct device_attribute *attr,
265 	     const char *buf, size_t count)
266 {
267 	struct thermal_zone_device *tz = to_thermal_zone(dev);
268 	char name[THERMAL_NAME_LENGTH];
269 	int ret;
270 
271 	snprintf(name, sizeof(name), "%s", buf);
272 
273 	ret = thermal_zone_device_set_policy(tz, name);
274 	if (!ret)
275 		ret = count;
276 
277 	return ret;
278 }
279 
280 static ssize_t
281 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
282 {
283 	struct thermal_zone_device *tz = to_thermal_zone(dev);
284 
285 	return sprintf(buf, "%s\n", tz->governor->name);
286 }
287 
288 static ssize_t
289 available_policies_show(struct device *dev, struct device_attribute *devattr,
290 			char *buf)
291 {
292 	return thermal_build_list_of_policies(buf);
293 }
294 
295 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
296 static ssize_t
297 emul_temp_store(struct device *dev, struct device_attribute *attr,
298 		const char *buf, size_t count)
299 {
300 	struct thermal_zone_device *tz = to_thermal_zone(dev);
301 	int ret = 0;
302 	int temperature;
303 
304 	if (kstrtoint(buf, 10, &temperature))
305 		return -EINVAL;
306 
307 	if (!tz->ops->set_emul_temp) {
308 		mutex_lock(&tz->lock);
309 		tz->emul_temperature = temperature;
310 		mutex_unlock(&tz->lock);
311 	} else {
312 		ret = tz->ops->set_emul_temp(tz, temperature);
313 	}
314 
315 	if (!ret)
316 		thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
317 
318 	return ret ? ret : count;
319 }
320 static DEVICE_ATTR(emul_temp, S_IWUSR, NULL, emul_temp_store);
321 #endif
322 
323 static ssize_t
324 sustainable_power_show(struct device *dev, struct device_attribute *devattr,
325 		       char *buf)
326 {
327 	struct thermal_zone_device *tz = to_thermal_zone(dev);
328 
329 	if (tz->tzp)
330 		return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
331 	else
332 		return -EIO;
333 }
334 
335 static ssize_t
336 sustainable_power_store(struct device *dev, struct device_attribute *devattr,
337 			const char *buf, size_t count)
338 {
339 	struct thermal_zone_device *tz = to_thermal_zone(dev);
340 	u32 sustainable_power;
341 
342 	if (!tz->tzp)
343 		return -EIO;
344 
345 	if (kstrtou32(buf, 10, &sustainable_power))
346 		return -EINVAL;
347 
348 	tz->tzp->sustainable_power = sustainable_power;
349 
350 	return count;
351 }
352 
353 #define create_s32_tzp_attr(name)					\
354 	static ssize_t							\
355 	name##_show(struct device *dev, struct device_attribute *devattr, \
356 		char *buf)						\
357 	{								\
358 	struct thermal_zone_device *tz = to_thermal_zone(dev);		\
359 									\
360 	if (tz->tzp)							\
361 		return sprintf(buf, "%d\n", tz->tzp->name);		\
362 	else								\
363 		return -EIO;						\
364 	}								\
365 									\
366 	static ssize_t							\
367 	name##_store(struct device *dev, struct device_attribute *devattr, \
368 		const char *buf, size_t count)				\
369 	{								\
370 		struct thermal_zone_device *tz = to_thermal_zone(dev);	\
371 		s32 value;						\
372 									\
373 		if (!tz->tzp)						\
374 			return -EIO;					\
375 									\
376 		if (kstrtos32(buf, 10, &value))				\
377 			return -EINVAL;					\
378 									\
379 		tz->tzp->name = value;					\
380 									\
381 		return count;						\
382 	}								\
383 	static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, name##_show, name##_store)
384 
385 create_s32_tzp_attr(k_po);
386 create_s32_tzp_attr(k_pu);
387 create_s32_tzp_attr(k_i);
388 create_s32_tzp_attr(k_d);
389 create_s32_tzp_attr(integral_cutoff);
390 create_s32_tzp_attr(slope);
391 create_s32_tzp_attr(offset);
392 #undef create_s32_tzp_attr
393 
394 /*
395  * These are thermal zone device attributes that will always be present.
396  * All the attributes created for tzp (create_s32_tzp_attr) also are always
397  * present on the sysfs interface.
398  */
399 static DEVICE_ATTR(type, 0444, type_show, NULL);
400 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
401 static DEVICE_ATTR(policy, S_IRUGO | S_IWUSR, policy_show, policy_store);
402 static DEVICE_ATTR(available_policies, S_IRUGO, available_policies_show, NULL);
403 static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,
404 		   sustainable_power_store);
405 
406 /* These thermal zone device attributes are created based on conditions */
407 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
408 static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, passive_store);
409 
410 /* These attributes are unconditionally added to a thermal zone */
411 static struct attribute *thermal_zone_dev_attrs[] = {
412 	&dev_attr_type.attr,
413 	&dev_attr_temp.attr,
414 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
415 	&dev_attr_emul_temp.attr,
416 #endif
417 	&dev_attr_policy.attr,
418 	&dev_attr_available_policies.attr,
419 	&dev_attr_sustainable_power.attr,
420 	&dev_attr_k_po.attr,
421 	&dev_attr_k_pu.attr,
422 	&dev_attr_k_i.attr,
423 	&dev_attr_k_d.attr,
424 	&dev_attr_integral_cutoff.attr,
425 	&dev_attr_slope.attr,
426 	&dev_attr_offset.attr,
427 	NULL,
428 };
429 
430 static struct attribute_group thermal_zone_attribute_group = {
431 	.attrs = thermal_zone_dev_attrs,
432 };
433 
434 /* We expose mode only if .get_mode is present */
435 static struct attribute *thermal_zone_mode_attrs[] = {
436 	&dev_attr_mode.attr,
437 	NULL,
438 };
439 
440 static umode_t thermal_zone_mode_is_visible(struct kobject *kobj,
441 					    struct attribute *attr,
442 					    int attrno)
443 {
444 	struct device *dev = container_of(kobj, struct device, kobj);
445 	struct thermal_zone_device *tz;
446 
447 	tz = container_of(dev, struct thermal_zone_device, device);
448 
449 	if (tz->ops->get_mode)
450 		return attr->mode;
451 
452 	return 0;
453 }
454 
455 static struct attribute_group thermal_zone_mode_attribute_group = {
456 	.attrs = thermal_zone_mode_attrs,
457 	.is_visible = thermal_zone_mode_is_visible,
458 };
459 
460 /* We expose passive only if passive trips are present */
461 static struct attribute *thermal_zone_passive_attrs[] = {
462 	&dev_attr_passive.attr,
463 	NULL,
464 };
465 
466 static umode_t thermal_zone_passive_is_visible(struct kobject *kobj,
467 					       struct attribute *attr,
468 					       int attrno)
469 {
470 	struct device *dev = container_of(kobj, struct device, kobj);
471 	struct thermal_zone_device *tz;
472 	enum thermal_trip_type trip_type;
473 	int count, passive = 0;
474 
475 	tz = container_of(dev, struct thermal_zone_device, device);
476 
477 	for (count = 0; count < tz->trips && !passive; count++) {
478 		tz->ops->get_trip_type(tz, count, &trip_type);
479 
480 		if (trip_type == THERMAL_TRIP_PASSIVE)
481 			passive = 1;
482 	}
483 
484 	if (!passive)
485 		return attr->mode;
486 
487 	return 0;
488 }
489 
490 static struct attribute_group thermal_zone_passive_attribute_group = {
491 	.attrs = thermal_zone_passive_attrs,
492 	.is_visible = thermal_zone_passive_is_visible,
493 };
494 
495 static const struct attribute_group *thermal_zone_attribute_groups[] = {
496 	&thermal_zone_attribute_group,
497 	&thermal_zone_mode_attribute_group,
498 	&thermal_zone_passive_attribute_group,
499 	/* This is not NULL terminated as we create the group dynamically */
500 };
501 
502 /**
503  * create_trip_attrs() - create attributes for trip points
504  * @tz:		the thermal zone device
505  * @mask:	Writeable trip point bitmap.
506  *
507  * helper function to instantiate sysfs entries for every trip
508  * point and its properties of a struct thermal_zone_device.
509  *
510  * Return: 0 on success, the proper error value otherwise.
511  */
512 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
513 {
514 	struct attribute **attrs;
515 	int indx;
516 
517 	/* This function works only for zones with at least one trip */
518 	if (tz->trips <= 0)
519 		return -EINVAL;
520 
521 	tz->trip_type_attrs = kcalloc(tz->trips, sizeof(*tz->trip_type_attrs),
522 				      GFP_KERNEL);
523 	if (!tz->trip_type_attrs)
524 		return -ENOMEM;
525 
526 	tz->trip_temp_attrs = kcalloc(tz->trips, sizeof(*tz->trip_temp_attrs),
527 				      GFP_KERNEL);
528 	if (!tz->trip_temp_attrs) {
529 		kfree(tz->trip_type_attrs);
530 		return -ENOMEM;
531 	}
532 
533 	if (tz->ops->get_trip_hyst) {
534 		tz->trip_hyst_attrs = kcalloc(tz->trips,
535 					      sizeof(*tz->trip_hyst_attrs),
536 					      GFP_KERNEL);
537 		if (!tz->trip_hyst_attrs) {
538 			kfree(tz->trip_type_attrs);
539 			kfree(tz->trip_temp_attrs);
540 			return -ENOMEM;
541 		}
542 	}
543 
544 	attrs = kcalloc(tz->trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
545 	if (!attrs) {
546 		kfree(tz->trip_type_attrs);
547 		kfree(tz->trip_temp_attrs);
548 		if (tz->ops->get_trip_hyst)
549 			kfree(tz->trip_hyst_attrs);
550 		return -ENOMEM;
551 	}
552 
553 	for (indx = 0; indx < tz->trips; indx++) {
554 		/* create trip type attribute */
555 		snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
556 			 "trip_point_%d_type", indx);
557 
558 		sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
559 		tz->trip_type_attrs[indx].attr.attr.name =
560 						tz->trip_type_attrs[indx].name;
561 		tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
562 		tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
563 		attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
564 
565 		/* create trip temp attribute */
566 		snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
567 			 "trip_point_%d_temp", indx);
568 
569 		sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
570 		tz->trip_temp_attrs[indx].attr.attr.name =
571 						tz->trip_temp_attrs[indx].name;
572 		tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
573 		tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
574 		if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
575 		    mask & (1 << indx)) {
576 			tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
577 			tz->trip_temp_attrs[indx].attr.store =
578 							trip_point_temp_store;
579 		}
580 		attrs[indx + tz->trips] = &tz->trip_temp_attrs[indx].attr.attr;
581 
582 		/* create Optional trip hyst attribute */
583 		if (!tz->ops->get_trip_hyst)
584 			continue;
585 		snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
586 			 "trip_point_%d_hyst", indx);
587 
588 		sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
589 		tz->trip_hyst_attrs[indx].attr.attr.name =
590 					tz->trip_hyst_attrs[indx].name;
591 		tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
592 		tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
593 		if (tz->ops->set_trip_hyst) {
594 			tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
595 			tz->trip_hyst_attrs[indx].attr.store =
596 					trip_point_hyst_store;
597 		}
598 		attrs[indx + tz->trips * 2] =
599 					&tz->trip_hyst_attrs[indx].attr.attr;
600 	}
601 	attrs[tz->trips * 3] = NULL;
602 
603 	tz->trips_attribute_group.attrs = attrs;
604 
605 	return 0;
606 }
607 
608 int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
609 				      int mask)
610 {
611 	const struct attribute_group **groups;
612 	int i, size, result;
613 
614 	/* we need one extra for trips and the NULL to terminate the array */
615 	size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
616 	/* This also takes care of API requirement to be NULL terminated */
617 	groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
618 	if (!groups)
619 		return -ENOMEM;
620 
621 	for (i = 0; i < size - 2; i++)
622 		groups[i] = thermal_zone_attribute_groups[i];
623 
624 	if (tz->trips) {
625 		result = create_trip_attrs(tz, mask);
626 		if (result) {
627 			kfree(groups);
628 
629 			return result;
630 		}
631 
632 		groups[size - 2] = &tz->trips_attribute_group;
633 	}
634 
635 	tz->device.groups = groups;
636 
637 	return 0;
638 }
639 
640 /* sys I/F for cooling device */
641 static ssize_t
642 thermal_cooling_device_type_show(struct device *dev,
643 				 struct device_attribute *attr, char *buf)
644 {
645 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
646 
647 	return sprintf(buf, "%s\n", cdev->type);
648 }
649 
650 static ssize_t
651 thermal_cooling_device_max_state_show(struct device *dev,
652 				      struct device_attribute *attr, char *buf)
653 {
654 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
655 	unsigned long state;
656 	int ret;
657 
658 	ret = cdev->ops->get_max_state(cdev, &state);
659 	if (ret)
660 		return ret;
661 	return sprintf(buf, "%ld\n", state);
662 }
663 
664 static ssize_t
665 thermal_cooling_device_cur_state_show(struct device *dev,
666 				      struct device_attribute *attr, char *buf)
667 {
668 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
669 	unsigned long state;
670 	int ret;
671 
672 	ret = cdev->ops->get_cur_state(cdev, &state);
673 	if (ret)
674 		return ret;
675 	return sprintf(buf, "%ld\n", state);
676 }
677 
678 static ssize_t
679 thermal_cooling_device_cur_state_store(struct device *dev,
680 				       struct device_attribute *attr,
681 				       const char *buf, size_t count)
682 {
683 	struct thermal_cooling_device *cdev = to_cooling_device(dev);
684 	unsigned long state;
685 	int result;
686 
687 	if (sscanf(buf, "%ld\n", &state) != 1)
688 		return -EINVAL;
689 
690 	if ((long)state < 0)
691 		return -EINVAL;
692 
693 	result = cdev->ops->set_cur_state(cdev, state);
694 	if (result)
695 		return result;
696 	return count;
697 }
698 
699 static struct device_attribute dev_attr_cdev_type =
700 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
701 static DEVICE_ATTR(max_state, 0444,
702 		   thermal_cooling_device_max_state_show, NULL);
703 static DEVICE_ATTR(cur_state, 0644,
704 		   thermal_cooling_device_cur_state_show,
705 		   thermal_cooling_device_cur_state_store);
706 
707 static struct attribute *cooling_device_attrs[] = {
708 	&dev_attr_cdev_type.attr,
709 	&dev_attr_max_state.attr,
710 	&dev_attr_cur_state.attr,
711 	NULL,
712 };
713 
714 static const struct attribute_group cooling_device_attr_group = {
715 	.attrs = cooling_device_attrs,
716 };
717 
718 static const struct attribute_group *cooling_device_attr_groups[] = {
719 	&cooling_device_attr_group,
720 	NULL,
721 };
722 
723 void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
724 {
725 	cdev->device.groups = cooling_device_attr_groups;
726 }
727 
728 /* these helper will be used only at the time of bindig */
729 ssize_t
730 thermal_cooling_device_trip_point_show(struct device *dev,
731 				       struct device_attribute *attr, char *buf)
732 {
733 	struct thermal_instance *instance;
734 
735 	instance =
736 	    container_of(attr, struct thermal_instance, attr);
737 
738 	if (instance->trip == THERMAL_TRIPS_NONE)
739 		return sprintf(buf, "-1\n");
740 	else
741 		return sprintf(buf, "%d\n", instance->trip);
742 }
743 
744 ssize_t
745 thermal_cooling_device_weight_show(struct device *dev,
746 				   struct device_attribute *attr, char *buf)
747 {
748 	struct thermal_instance *instance;
749 
750 	instance = container_of(attr, struct thermal_instance, weight_attr);
751 
752 	return sprintf(buf, "%d\n", instance->weight);
753 }
754 
755 ssize_t
756 thermal_cooling_device_weight_store(struct device *dev,
757 				    struct device_attribute *attr,
758 				    const char *buf, size_t count)
759 {
760 	struct thermal_instance *instance;
761 	int ret, weight;
762 
763 	ret = kstrtoint(buf, 0, &weight);
764 	if (ret)
765 		return ret;
766 
767 	instance = container_of(attr, struct thermal_instance, weight_attr);
768 	instance->weight = weight;
769 
770 	return count;
771 }
772