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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Power capping class
  4 * Copyright (c) 2013, Intel Corporation.
  5 */
  6
  7#include <linux/module.h>
  8#include <linux/device.h>
  9#include <linux/err.h>
 10#include <linux/kstrtox.h>
 11#include <linux/slab.h>
 12#include <linux/powercap.h>
 13
 14#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev)
 15#define to_powercap_control_type(n) \
 16			container_of(n, struct powercap_control_type, dev)
 17
 18/* Power zone show function */
 19#define define_power_zone_show(_attr)		\
 20static ssize_t _attr##_show(struct device *dev, \
 21					struct device_attribute *dev_attr,\
 22					char *buf) \
 23{ \
 24	u64 value; \
 25	ssize_t len = -EINVAL; \
 26	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 27	\
 28	if (power_zone->ops->get_##_attr) { \
 29		if (!power_zone->ops->get_##_attr(power_zone, &value)) \
 30			len = sprintf(buf, "%lld\n", value); \
 31	} \
 32	\
 33	return len; \
 34}
 35
 36/* The only meaningful input is 0 (reset), others are silently ignored */
 37#define define_power_zone_store(_attr)		\
 38static ssize_t _attr##_store(struct device *dev,\
 39				struct device_attribute *dev_attr, \
 40				const char *buf, size_t count) \
 41{ \
 42	int err; \
 43	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 44	u64 value; \
 45	\
 46	err = kstrtoull(buf, 10, &value); \
 47	if (err) \
 48		return -EINVAL; \
 49	if (value) \
 50		return count; \
 51	if (power_zone->ops->reset_##_attr) { \
 52		if (!power_zone->ops->reset_##_attr(power_zone)) \
 53			return count; \
 54	} \
 55	\
 56	return -EINVAL; \
 57}
 58
 59/* Power zone constraint show function */
 60#define define_power_zone_constraint_show(_attr) \
 61static ssize_t show_constraint_##_attr(struct device *dev, \
 62				struct device_attribute *dev_attr,\
 63				char *buf) \
 64{ \
 65	u64 value; \
 66	ssize_t len = -ENODATA; \
 67	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 68	int id; \
 69	struct powercap_zone_constraint *pconst;\
 70	\
 71	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
 72		return -EINVAL; \
 73	if (id >= power_zone->const_id_cnt)	\
 74		return -EINVAL; \
 75	pconst = &power_zone->constraints[id]; \
 76	if (pconst && pconst->ops && pconst->ops->get_##_attr) { \
 77		if (!pconst->ops->get_##_attr(power_zone, id, &value)) \
 78			len = sprintf(buf, "%lld\n", value); \
 79	} \
 80	\
 81	return len; \
 82}
 83
 84/* Power zone constraint store function */
 85#define define_power_zone_constraint_store(_attr) \
 86static ssize_t store_constraint_##_attr(struct device *dev,\
 87				struct device_attribute *dev_attr, \
 88				const char *buf, size_t count) \
 89{ \
 90	int err; \
 91	u64 value; \
 92	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 93	int id; \
 94	struct powercap_zone_constraint *pconst;\
 95	\
 96	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
 97		return -EINVAL; \
 98	if (id >= power_zone->const_id_cnt)	\
 99		return -EINVAL; \
100	pconst = &power_zone->constraints[id]; \
101	err = kstrtoull(buf, 10, &value); \
102	if (err) \
103		return -EINVAL; \
104	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
105		if (!pconst->ops->set_##_attr(power_zone, id, value)) \
106			return count; \
107	} \
108	\
109	return -ENODATA; \
110}
111
112/* Power zone information callbacks */
113define_power_zone_show(power_uw);
114define_power_zone_show(max_power_range_uw);
115define_power_zone_show(energy_uj);
116define_power_zone_store(energy_uj);
117define_power_zone_show(max_energy_range_uj);
118
119/* Power zone attributes */
120static DEVICE_ATTR_RO(max_power_range_uw);
121static DEVICE_ATTR_RO(power_uw);
122static DEVICE_ATTR_RO(max_energy_range_uj);
123static DEVICE_ATTR_RW(energy_uj);
124
125/* Power zone constraint attributes callbacks */
126define_power_zone_constraint_show(power_limit_uw);
127define_power_zone_constraint_store(power_limit_uw);
128define_power_zone_constraint_show(time_window_us);
129define_power_zone_constraint_store(time_window_us);
130define_power_zone_constraint_show(max_power_uw);
131define_power_zone_constraint_show(min_power_uw);
132define_power_zone_constraint_show(max_time_window_us);
133define_power_zone_constraint_show(min_time_window_us);
134
135/* For one time seeding of constraint device attributes */
136struct powercap_constraint_attr {
137	struct device_attribute power_limit_attr;
138	struct device_attribute time_window_attr;
139	struct device_attribute max_power_attr;
140	struct device_attribute min_power_attr;
141	struct device_attribute max_time_window_attr;
142	struct device_attribute min_time_window_attr;
143	struct device_attribute name_attr;
144};
145
146static struct powercap_constraint_attr
147				constraint_attrs[MAX_CONSTRAINTS_PER_ZONE];
148
149/* A list of powercap control_types */
150static LIST_HEAD(powercap_cntrl_list);
151/* Mutex to protect list of powercap control_types */
152static DEFINE_MUTEX(powercap_cntrl_list_lock);
153
154#define POWERCAP_CONSTRAINT_NAME_LEN	30 /* Some limit to avoid overflow */
155static ssize_t show_constraint_name(struct device *dev,
156				struct device_attribute *dev_attr,
157				char *buf)
158{
159	const char *name;
160	struct powercap_zone *power_zone = to_powercap_zone(dev);
161	int id;
162	ssize_t len = -ENODATA;
163	struct powercap_zone_constraint *pconst;
164
165	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id))
166		return -EINVAL;
167	if (id >= power_zone->const_id_cnt)
168		return -EINVAL;
169	pconst = &power_zone->constraints[id];
170
171	if (pconst && pconst->ops && pconst->ops->get_name) {
172		name = pconst->ops->get_name(power_zone, id);
173		if (name) {
174			sprintf(buf, "%.*s\n", POWERCAP_CONSTRAINT_NAME_LEN - 1,
175				name);
176			len = strlen(buf);
177		}
178	}
179
180	return len;
181}
182
183static int create_constraint_attribute(int id, const char *name,
184				int mode,
185				struct device_attribute *dev_attr,
186				ssize_t (*show)(struct device *,
187					struct device_attribute *, char *),
188				ssize_t (*store)(struct device *,
189					struct device_attribute *,
190				const char *, size_t)
191				)
192{
193
194	dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s",
195								id, name);
196	if (!dev_attr->attr.name)
197		return -ENOMEM;
198	dev_attr->attr.mode = mode;
199	dev_attr->show = show;
200	dev_attr->store = store;
201
202	return 0;
203}
204
205static void free_constraint_attributes(void)
206{
207	int i;
208
209	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
210		kfree(constraint_attrs[i].power_limit_attr.attr.name);
211		kfree(constraint_attrs[i].time_window_attr.attr.name);
212		kfree(constraint_attrs[i].name_attr.attr.name);
213		kfree(constraint_attrs[i].max_power_attr.attr.name);
214		kfree(constraint_attrs[i].min_power_attr.attr.name);
215		kfree(constraint_attrs[i].max_time_window_attr.attr.name);
216		kfree(constraint_attrs[i].min_time_window_attr.attr.name);
217	}
218}
219
220static int seed_constraint_attributes(void)
221{
222	int i;
223	int ret;
224
225	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
226		ret = create_constraint_attribute(i, "power_limit_uw",
227					S_IWUSR | S_IRUGO,
228					&constraint_attrs[i].power_limit_attr,
229					show_constraint_power_limit_uw,
230					store_constraint_power_limit_uw);
231		if (ret)
232			goto err_alloc;
233		ret = create_constraint_attribute(i, "time_window_us",
234					S_IWUSR | S_IRUGO,
235					&constraint_attrs[i].time_window_attr,
236					show_constraint_time_window_us,
237					store_constraint_time_window_us);
238		if (ret)
239			goto err_alloc;
240		ret = create_constraint_attribute(i, "name", S_IRUGO,
241				&constraint_attrs[i].name_attr,
242				show_constraint_name,
243				NULL);
244		if (ret)
245			goto err_alloc;
246		ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO,
247				&constraint_attrs[i].max_power_attr,
248				show_constraint_max_power_uw,
249				NULL);
250		if (ret)
251			goto err_alloc;
252		ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO,
253				&constraint_attrs[i].min_power_attr,
254				show_constraint_min_power_uw,
255				NULL);
256		if (ret)
257			goto err_alloc;
258		ret = create_constraint_attribute(i, "max_time_window_us",
259				S_IRUGO,
260				&constraint_attrs[i].max_time_window_attr,
261				show_constraint_max_time_window_us,
262				NULL);
263		if (ret)
264			goto err_alloc;
265		ret = create_constraint_attribute(i, "min_time_window_us",
266				S_IRUGO,
267				&constraint_attrs[i].min_time_window_attr,
268				show_constraint_min_time_window_us,
269				NULL);
270		if (ret)
271			goto err_alloc;
272
273	}
274
275	return 0;
276
277err_alloc:
278	free_constraint_attributes();
279
280	return ret;
281}
282
283static int create_constraints(struct powercap_zone *power_zone,
284			int nr_constraints,
285			const struct powercap_zone_constraint_ops *const_ops)
286{
287	int i;
288	int ret = 0;
289	int count;
290	struct powercap_zone_constraint *pconst;
291
292	if (!power_zone || !const_ops || !const_ops->get_power_limit_uw ||
293					!const_ops->set_power_limit_uw ||
294					!const_ops->get_time_window_us ||
295					!const_ops->set_time_window_us)
296		return -EINVAL;
297
298	count = power_zone->zone_attr_count;
299	for (i = 0; i < nr_constraints; ++i) {
300		pconst = &power_zone->constraints[i];
301		pconst->ops = const_ops;
302		pconst->id = power_zone->const_id_cnt;
303		power_zone->const_id_cnt++;
304		power_zone->zone_dev_attrs[count++] =
305				&constraint_attrs[i].power_limit_attr.attr;
306		power_zone->zone_dev_attrs[count++] =
307				&constraint_attrs[i].time_window_attr.attr;
308		if (pconst->ops->get_name)
309			power_zone->zone_dev_attrs[count++] =
310				&constraint_attrs[i].name_attr.attr;
311		if (pconst->ops->get_max_power_uw)
312			power_zone->zone_dev_attrs[count++] =
313				&constraint_attrs[i].max_power_attr.attr;
314		if (pconst->ops->get_min_power_uw)
315			power_zone->zone_dev_attrs[count++] =
316				&constraint_attrs[i].min_power_attr.attr;
317		if (pconst->ops->get_max_time_window_us)
318			power_zone->zone_dev_attrs[count++] =
319				&constraint_attrs[i].max_time_window_attr.attr;
320		if (pconst->ops->get_min_time_window_us)
321			power_zone->zone_dev_attrs[count++] =
322				&constraint_attrs[i].min_time_window_attr.attr;
323	}
324	power_zone->zone_attr_count = count;
325
326	return ret;
327}
328
329static bool control_type_valid(void *control_type)
330{
331	struct powercap_control_type *pos = NULL;
332	bool found = false;
333
334	mutex_lock(&powercap_cntrl_list_lock);
335
336	list_for_each_entry(pos, &powercap_cntrl_list, node) {
337		if (pos == control_type) {
338			found = true;
339			break;
340		}
341	}
342	mutex_unlock(&powercap_cntrl_list_lock);
343
344	return found;
345}
346
347static ssize_t name_show(struct device *dev,
348				struct device_attribute *attr,
349				char *buf)
350{
351	struct powercap_zone *power_zone = to_powercap_zone(dev);
352
353	return sprintf(buf, "%s\n", power_zone->name);
354}
355
356static DEVICE_ATTR_RO(name);
357
358/* Create zone and attributes in sysfs */
359static void create_power_zone_common_attributes(
360					struct powercap_zone *power_zone)
361{
362	int count = 0;
363
364	power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr;
365	if (power_zone->ops->get_max_energy_range_uj)
366		power_zone->zone_dev_attrs[count++] =
367					&dev_attr_max_energy_range_uj.attr;
368	if (power_zone->ops->get_energy_uj) {
369		if (power_zone->ops->reset_energy_uj)
370			dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUSR;
371		else
372			dev_attr_energy_uj.attr.mode = S_IRUSR;
373		power_zone->zone_dev_attrs[count++] =
374					&dev_attr_energy_uj.attr;
375	}
376	if (power_zone->ops->get_power_uw)
377		power_zone->zone_dev_attrs[count++] =
378					&dev_attr_power_uw.attr;
379	if (power_zone->ops->get_max_power_range_uw)
380		power_zone->zone_dev_attrs[count++] =
381					&dev_attr_max_power_range_uw.attr;
382	power_zone->zone_dev_attrs[count] = NULL;
383	power_zone->zone_attr_count = count;
384}
385
386static void powercap_release(struct device *dev)
387{
388	bool allocated;
389
390	if (dev->parent) {
391		struct powercap_zone *power_zone = to_powercap_zone(dev);
392
393		/* Store flag as the release() may free memory */
394		allocated = power_zone->allocated;
395		/* Remove id from parent idr struct */
396		idr_remove(power_zone->parent_idr, power_zone->id);
397		/* Destroy idrs allocated for this zone */
398		idr_destroy(&power_zone->idr);
399		kfree(power_zone->name);
400		kfree(power_zone->zone_dev_attrs);
401		kfree(power_zone->constraints);
402		if (power_zone->ops->release)
403			power_zone->ops->release(power_zone);
404		if (allocated)
405			kfree(power_zone);
406	} else {
407		struct powercap_control_type *control_type =
408						to_powercap_control_type(dev);
409
410		/* Store flag as the release() may free memory */
411		allocated = control_type->allocated;
412		idr_destroy(&control_type->idr);
413		mutex_destroy(&control_type->lock);
414		if (control_type->ops && control_type->ops->release)
415			control_type->ops->release(control_type);
416		if (allocated)
417			kfree(control_type);
418	}
419}
420
421static ssize_t enabled_show(struct device *dev,
422				struct device_attribute *attr,
423				char *buf)
424{
425	bool mode = true;
426
427	/* Default is enabled */
428	if (dev->parent) {
429		struct powercap_zone *power_zone = to_powercap_zone(dev);
430		if (power_zone->ops->get_enable)
431			if (power_zone->ops->get_enable(power_zone, &mode))
432				mode = false;
433	} else {
434		struct powercap_control_type *control_type =
435						to_powercap_control_type(dev);
436		if (control_type->ops && control_type->ops->get_enable)
437			if (control_type->ops->get_enable(control_type, &mode))
438				mode = false;
439	}
440
441	return sprintf(buf, "%d\n", mode);
442}
443
444static ssize_t enabled_store(struct device *dev,
445				struct device_attribute *attr,
446				const char *buf,  size_t len)
447{
448	bool mode;
449
450	if (kstrtobool(buf, &mode))
451		return -EINVAL;
452	if (dev->parent) {
453		struct powercap_zone *power_zone = to_powercap_zone(dev);
454		if (power_zone->ops->set_enable)
455			if (!power_zone->ops->set_enable(power_zone, mode))
456				return len;
457	} else {
458		struct powercap_control_type *control_type =
459						to_powercap_control_type(dev);
460		if (control_type->ops && control_type->ops->set_enable)
461			if (!control_type->ops->set_enable(control_type, mode))
462				return len;
463	}
464
465	return -ENOSYS;
466}
467
468static DEVICE_ATTR_RW(enabled);
469
470static struct attribute *powercap_attrs[] = {
471	&dev_attr_enabled.attr,
472	NULL,
473};
474ATTRIBUTE_GROUPS(powercap);
475
476static struct class powercap_class = {
477	.name = "powercap",
478	.dev_release = powercap_release,
479	.dev_groups = powercap_groups,
480};
481
482struct powercap_zone *powercap_register_zone(
483			struct powercap_zone *power_zone,
484			struct powercap_control_type *control_type,
485			const char *name,
486			struct powercap_zone *parent,
487			const struct powercap_zone_ops *ops,
488			int nr_constraints,
489			const struct powercap_zone_constraint_ops *const_ops)
490{
491	int result;
492	int nr_attrs;
493
494	if (!name || !control_type || !ops ||
495			nr_constraints > MAX_CONSTRAINTS_PER_ZONE ||
496			(!ops->get_energy_uj && !ops->get_power_uw) ||
497			!control_type_valid(control_type))
498		return ERR_PTR(-EINVAL);
499
500	if (power_zone) {
501		if (!ops->release)
502			return ERR_PTR(-EINVAL);
503		memset(power_zone, 0, sizeof(*power_zone));
504	} else {
505		power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL);
506		if (!power_zone)
507			return ERR_PTR(-ENOMEM);
508		power_zone->allocated = true;
509	}
510	power_zone->ops = ops;
511	power_zone->control_type_inst = control_type;
512	if (!parent) {
513		power_zone->dev.parent = &control_type->dev;
514		power_zone->parent_idr = &control_type->idr;
515	} else {
516		power_zone->dev.parent = &parent->dev;
517		power_zone->parent_idr = &parent->idr;
518	}
519	power_zone->dev.class = &powercap_class;
520
521	mutex_lock(&control_type->lock);
522	/* Using idr to get the unique id */
523	result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL);
524	if (result < 0)
525		goto err_idr_alloc;
526
527	power_zone->id = result;
528	idr_init(&power_zone->idr);
529	result = -ENOMEM;
530	power_zone->name = kstrdup(name, GFP_KERNEL);
531	if (!power_zone->name)
532		goto err_name_alloc;
 
 
 
533	power_zone->constraints = kcalloc(nr_constraints,
534					  sizeof(*power_zone->constraints),
535					  GFP_KERNEL);
536	if (!power_zone->constraints)
537		goto err_const_alloc;
538
539	nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS +
540						POWERCAP_ZONE_MAX_ATTRS + 1;
541	power_zone->zone_dev_attrs = kcalloc(nr_attrs, sizeof(void *),
542					     GFP_KERNEL);
543	if (!power_zone->zone_dev_attrs)
544		goto err_attr_alloc;
545	create_power_zone_common_attributes(power_zone);
546	result = create_constraints(power_zone, nr_constraints, const_ops);
547	if (result)
548		goto err_dev_ret;
549
550	power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL;
551	power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs;
552	power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
553	power_zone->dev_attr_groups[1] = NULL;
554	power_zone->dev.groups = power_zone->dev_attr_groups;
555	dev_set_name(&power_zone->dev, "%s:%x",
556					dev_name(power_zone->dev.parent),
557					power_zone->id);
558	result = device_register(&power_zone->dev);
559	if (result) {
560		put_device(&power_zone->dev);
561		mutex_unlock(&control_type->lock);
562
563		return ERR_PTR(result);
564	}
565
566	control_type->nr_zones++;
567	mutex_unlock(&control_type->lock);
568
569	return power_zone;
570
571err_dev_ret:
572	kfree(power_zone->zone_dev_attrs);
573err_attr_alloc:
574	kfree(power_zone->constraints);
575err_const_alloc:
576	kfree(power_zone->name);
577err_name_alloc:
578	idr_remove(power_zone->parent_idr, power_zone->id);
579err_idr_alloc:
580	if (power_zone->allocated)
581		kfree(power_zone);
582	mutex_unlock(&control_type->lock);
583
584	return ERR_PTR(result);
585}
586EXPORT_SYMBOL_GPL(powercap_register_zone);
587
588int powercap_unregister_zone(struct powercap_control_type *control_type,
589				struct powercap_zone *power_zone)
590{
591	if (!power_zone || !control_type)
592		return -EINVAL;
593
594	mutex_lock(&control_type->lock);
595	control_type->nr_zones--;
596	mutex_unlock(&control_type->lock);
597
598	device_unregister(&power_zone->dev);
599
600	return 0;
601}
602EXPORT_SYMBOL_GPL(powercap_unregister_zone);
603
604struct powercap_control_type *powercap_register_control_type(
605				struct powercap_control_type *control_type,
606				const char *name,
607				const struct powercap_control_type_ops *ops)
608{
609	int result;
610
611	if (!name)
612		return ERR_PTR(-EINVAL);
613	if (control_type) {
614		if (!ops || !ops->release)
615			return ERR_PTR(-EINVAL);
616		memset(control_type, 0, sizeof(*control_type));
617	} else {
618		control_type = kzalloc(sizeof(*control_type), GFP_KERNEL);
619		if (!control_type)
620			return ERR_PTR(-ENOMEM);
621		control_type->allocated = true;
622	}
623	mutex_init(&control_type->lock);
624	control_type->ops = ops;
625	INIT_LIST_HEAD(&control_type->node);
626	control_type->dev.class = &powercap_class;
627	dev_set_name(&control_type->dev, "%s", name);
628	result = device_register(&control_type->dev);
629	if (result) {
630		if (control_type->allocated)
631			kfree(control_type);
632		return ERR_PTR(result);
633	}
634	idr_init(&control_type->idr);
635
636	mutex_lock(&powercap_cntrl_list_lock);
637	list_add_tail(&control_type->node, &powercap_cntrl_list);
638	mutex_unlock(&powercap_cntrl_list_lock);
639
640	return control_type;
641}
642EXPORT_SYMBOL_GPL(powercap_register_control_type);
643
644int powercap_unregister_control_type(struct powercap_control_type *control_type)
645{
646	struct powercap_control_type *pos = NULL;
647
648	if (control_type->nr_zones) {
649		dev_err(&control_type->dev, "Zones of this type still not freed\n");
650		return -EINVAL;
651	}
652	mutex_lock(&powercap_cntrl_list_lock);
653	list_for_each_entry(pos, &powercap_cntrl_list, node) {
654		if (pos == control_type) {
655			list_del(&control_type->node);
656			mutex_unlock(&powercap_cntrl_list_lock);
657			device_unregister(&control_type->dev);
658			return 0;
659		}
660	}
661	mutex_unlock(&powercap_cntrl_list_lock);
662
663	return -ENODEV;
664}
665EXPORT_SYMBOL_GPL(powercap_unregister_control_type);
666
667static int __init powercap_init(void)
668{
669	int result;
670
671	result = seed_constraint_attributes();
672	if (result)
673		return result;
674
675	return class_register(&powercap_class);
676}
677
678fs_initcall(powercap_init);
679
680MODULE_DESCRIPTION("PowerCap sysfs Driver");
681MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Power capping class
  4 * Copyright (c) 2013, Intel Corporation.
  5 */
  6
  7#include <linux/module.h>
  8#include <linux/device.h>
  9#include <linux/err.h>
 
 10#include <linux/slab.h>
 11#include <linux/powercap.h>
 12
 13#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev)
 14#define to_powercap_control_type(n) \
 15			container_of(n, struct powercap_control_type, dev)
 16
 17/* Power zone show function */
 18#define define_power_zone_show(_attr)		\
 19static ssize_t _attr##_show(struct device *dev, \
 20					struct device_attribute *dev_attr,\
 21					char *buf) \
 22{ \
 23	u64 value; \
 24	ssize_t len = -EINVAL; \
 25	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 26	\
 27	if (power_zone->ops->get_##_attr) { \
 28		if (!power_zone->ops->get_##_attr(power_zone, &value)) \
 29			len = sprintf(buf, "%lld\n", value); \
 30	} \
 31	\
 32	return len; \
 33}
 34
 35/* The only meaningful input is 0 (reset), others are silently ignored */
 36#define define_power_zone_store(_attr)		\
 37static ssize_t _attr##_store(struct device *dev,\
 38				struct device_attribute *dev_attr, \
 39				const char *buf, size_t count) \
 40{ \
 41	int err; \
 42	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 43	u64 value; \
 44	\
 45	err = kstrtoull(buf, 10, &value); \
 46	if (err) \
 47		return -EINVAL; \
 48	if (value) \
 49		return count; \
 50	if (power_zone->ops->reset_##_attr) { \
 51		if (!power_zone->ops->reset_##_attr(power_zone)) \
 52			return count; \
 53	} \
 54	\
 55	return -EINVAL; \
 56}
 57
 58/* Power zone constraint show function */
 59#define define_power_zone_constraint_show(_attr) \
 60static ssize_t show_constraint_##_attr(struct device *dev, \
 61				struct device_attribute *dev_attr,\
 62				char *buf) \
 63{ \
 64	u64 value; \
 65	ssize_t len = -ENODATA; \
 66	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 67	int id; \
 68	struct powercap_zone_constraint *pconst;\
 69	\
 70	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
 71		return -EINVAL; \
 72	if (id >= power_zone->const_id_cnt)	\
 73		return -EINVAL; \
 74	pconst = &power_zone->constraints[id]; \
 75	if (pconst && pconst->ops && pconst->ops->get_##_attr) { \
 76		if (!pconst->ops->get_##_attr(power_zone, id, &value)) \
 77			len = sprintf(buf, "%lld\n", value); \
 78	} \
 79	\
 80	return len; \
 81}
 82
 83/* Power zone constraint store function */
 84#define define_power_zone_constraint_store(_attr) \
 85static ssize_t store_constraint_##_attr(struct device *dev,\
 86				struct device_attribute *dev_attr, \
 87				const char *buf, size_t count) \
 88{ \
 89	int err; \
 90	u64 value; \
 91	struct powercap_zone *power_zone = to_powercap_zone(dev); \
 92	int id; \
 93	struct powercap_zone_constraint *pconst;\
 94	\
 95	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
 96		return -EINVAL; \
 97	if (id >= power_zone->const_id_cnt)	\
 98		return -EINVAL; \
 99	pconst = &power_zone->constraints[id]; \
100	err = kstrtoull(buf, 10, &value); \
101	if (err) \
102		return -EINVAL; \
103	if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
104		if (!pconst->ops->set_##_attr(power_zone, id, value)) \
105			return count; \
106	} \
107	\
108	return -ENODATA; \
109}
110
111/* Power zone information callbacks */
112define_power_zone_show(power_uw);
113define_power_zone_show(max_power_range_uw);
114define_power_zone_show(energy_uj);
115define_power_zone_store(energy_uj);
116define_power_zone_show(max_energy_range_uj);
117
118/* Power zone attributes */
119static DEVICE_ATTR_RO(max_power_range_uw);
120static DEVICE_ATTR_RO(power_uw);
121static DEVICE_ATTR_RO(max_energy_range_uj);
122static DEVICE_ATTR_RW(energy_uj);
123
124/* Power zone constraint attributes callbacks */
125define_power_zone_constraint_show(power_limit_uw);
126define_power_zone_constraint_store(power_limit_uw);
127define_power_zone_constraint_show(time_window_us);
128define_power_zone_constraint_store(time_window_us);
129define_power_zone_constraint_show(max_power_uw);
130define_power_zone_constraint_show(min_power_uw);
131define_power_zone_constraint_show(max_time_window_us);
132define_power_zone_constraint_show(min_time_window_us);
133
134/* For one time seeding of constraint device attributes */
135struct powercap_constraint_attr {
136	struct device_attribute power_limit_attr;
137	struct device_attribute time_window_attr;
138	struct device_attribute max_power_attr;
139	struct device_attribute min_power_attr;
140	struct device_attribute max_time_window_attr;
141	struct device_attribute min_time_window_attr;
142	struct device_attribute name_attr;
143};
144
145static struct powercap_constraint_attr
146				constraint_attrs[MAX_CONSTRAINTS_PER_ZONE];
147
148/* A list of powercap control_types */
149static LIST_HEAD(powercap_cntrl_list);
150/* Mutex to protect list of powercap control_types */
151static DEFINE_MUTEX(powercap_cntrl_list_lock);
152
153#define POWERCAP_CONSTRAINT_NAME_LEN	30 /* Some limit to avoid overflow */
154static ssize_t show_constraint_name(struct device *dev,
155				struct device_attribute *dev_attr,
156				char *buf)
157{
158	const char *name;
159	struct powercap_zone *power_zone = to_powercap_zone(dev);
160	int id;
161	ssize_t len = -ENODATA;
162	struct powercap_zone_constraint *pconst;
163
164	if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id))
165		return -EINVAL;
166	if (id >= power_zone->const_id_cnt)
167		return -EINVAL;
168	pconst = &power_zone->constraints[id];
169
170	if (pconst && pconst->ops && pconst->ops->get_name) {
171		name = pconst->ops->get_name(power_zone, id);
172		if (name) {
173			sprintf(buf, "%.*s\n", POWERCAP_CONSTRAINT_NAME_LEN - 1,
174				name);
175			len = strlen(buf);
176		}
177	}
178
179	return len;
180}
181
182static int create_constraint_attribute(int id, const char *name,
183				int mode,
184				struct device_attribute *dev_attr,
185				ssize_t (*show)(struct device *,
186					struct device_attribute *, char *),
187				ssize_t (*store)(struct device *,
188					struct device_attribute *,
189				const char *, size_t)
190				)
191{
192
193	dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s",
194								id, name);
195	if (!dev_attr->attr.name)
196		return -ENOMEM;
197	dev_attr->attr.mode = mode;
198	dev_attr->show = show;
199	dev_attr->store = store;
200
201	return 0;
202}
203
204static void free_constraint_attributes(void)
205{
206	int i;
207
208	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
209		kfree(constraint_attrs[i].power_limit_attr.attr.name);
210		kfree(constraint_attrs[i].time_window_attr.attr.name);
211		kfree(constraint_attrs[i].name_attr.attr.name);
212		kfree(constraint_attrs[i].max_power_attr.attr.name);
213		kfree(constraint_attrs[i].min_power_attr.attr.name);
214		kfree(constraint_attrs[i].max_time_window_attr.attr.name);
215		kfree(constraint_attrs[i].min_time_window_attr.attr.name);
216	}
217}
218
219static int seed_constraint_attributes(void)
220{
221	int i;
222	int ret;
223
224	for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
225		ret = create_constraint_attribute(i, "power_limit_uw",
226					S_IWUSR | S_IRUGO,
227					&constraint_attrs[i].power_limit_attr,
228					show_constraint_power_limit_uw,
229					store_constraint_power_limit_uw);
230		if (ret)
231			goto err_alloc;
232		ret = create_constraint_attribute(i, "time_window_us",
233					S_IWUSR | S_IRUGO,
234					&constraint_attrs[i].time_window_attr,
235					show_constraint_time_window_us,
236					store_constraint_time_window_us);
237		if (ret)
238			goto err_alloc;
239		ret = create_constraint_attribute(i, "name", S_IRUGO,
240				&constraint_attrs[i].name_attr,
241				show_constraint_name,
242				NULL);
243		if (ret)
244			goto err_alloc;
245		ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO,
246				&constraint_attrs[i].max_power_attr,
247				show_constraint_max_power_uw,
248				NULL);
249		if (ret)
250			goto err_alloc;
251		ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO,
252				&constraint_attrs[i].min_power_attr,
253				show_constraint_min_power_uw,
254				NULL);
255		if (ret)
256			goto err_alloc;
257		ret = create_constraint_attribute(i, "max_time_window_us",
258				S_IRUGO,
259				&constraint_attrs[i].max_time_window_attr,
260				show_constraint_max_time_window_us,
261				NULL);
262		if (ret)
263			goto err_alloc;
264		ret = create_constraint_attribute(i, "min_time_window_us",
265				S_IRUGO,
266				&constraint_attrs[i].min_time_window_attr,
267				show_constraint_min_time_window_us,
268				NULL);
269		if (ret)
270			goto err_alloc;
271
272	}
273
274	return 0;
275
276err_alloc:
277	free_constraint_attributes();
278
279	return ret;
280}
281
282static int create_constraints(struct powercap_zone *power_zone,
283			int nr_constraints,
284			const struct powercap_zone_constraint_ops *const_ops)
285{
286	int i;
287	int ret = 0;
288	int count;
289	struct powercap_zone_constraint *pconst;
290
291	if (!power_zone || !const_ops || !const_ops->get_power_limit_uw ||
292					!const_ops->set_power_limit_uw ||
293					!const_ops->get_time_window_us ||
294					!const_ops->set_time_window_us)
295		return -EINVAL;
296
297	count = power_zone->zone_attr_count;
298	for (i = 0; i < nr_constraints; ++i) {
299		pconst = &power_zone->constraints[i];
300		pconst->ops = const_ops;
301		pconst->id = power_zone->const_id_cnt;
302		power_zone->const_id_cnt++;
303		power_zone->zone_dev_attrs[count++] =
304				&constraint_attrs[i].power_limit_attr.attr;
305		power_zone->zone_dev_attrs[count++] =
306				&constraint_attrs[i].time_window_attr.attr;
307		if (pconst->ops->get_name)
308			power_zone->zone_dev_attrs[count++] =
309				&constraint_attrs[i].name_attr.attr;
310		if (pconst->ops->get_max_power_uw)
311			power_zone->zone_dev_attrs[count++] =
312				&constraint_attrs[i].max_power_attr.attr;
313		if (pconst->ops->get_min_power_uw)
314			power_zone->zone_dev_attrs[count++] =
315				&constraint_attrs[i].min_power_attr.attr;
316		if (pconst->ops->get_max_time_window_us)
317			power_zone->zone_dev_attrs[count++] =
318				&constraint_attrs[i].max_time_window_attr.attr;
319		if (pconst->ops->get_min_time_window_us)
320			power_zone->zone_dev_attrs[count++] =
321				&constraint_attrs[i].min_time_window_attr.attr;
322	}
323	power_zone->zone_attr_count = count;
324
325	return ret;
326}
327
328static bool control_type_valid(void *control_type)
329{
330	struct powercap_control_type *pos = NULL;
331	bool found = false;
332
333	mutex_lock(&powercap_cntrl_list_lock);
334
335	list_for_each_entry(pos, &powercap_cntrl_list, node) {
336		if (pos == control_type) {
337			found = true;
338			break;
339		}
340	}
341	mutex_unlock(&powercap_cntrl_list_lock);
342
343	return found;
344}
345
346static ssize_t name_show(struct device *dev,
347				struct device_attribute *attr,
348				char *buf)
349{
350	struct powercap_zone *power_zone = to_powercap_zone(dev);
351
352	return sprintf(buf, "%s\n", power_zone->name);
353}
354
355static DEVICE_ATTR_RO(name);
356
357/* Create zone and attributes in sysfs */
358static void create_power_zone_common_attributes(
359					struct powercap_zone *power_zone)
360{
361	int count = 0;
362
363	power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr;
364	if (power_zone->ops->get_max_energy_range_uj)
365		power_zone->zone_dev_attrs[count++] =
366					&dev_attr_max_energy_range_uj.attr;
367	if (power_zone->ops->get_energy_uj) {
368		if (power_zone->ops->reset_energy_uj)
369			dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUSR;
370		else
371			dev_attr_energy_uj.attr.mode = S_IRUSR;
372		power_zone->zone_dev_attrs[count++] =
373					&dev_attr_energy_uj.attr;
374	}
375	if (power_zone->ops->get_power_uw)
376		power_zone->zone_dev_attrs[count++] =
377					&dev_attr_power_uw.attr;
378	if (power_zone->ops->get_max_power_range_uw)
379		power_zone->zone_dev_attrs[count++] =
380					&dev_attr_max_power_range_uw.attr;
381	power_zone->zone_dev_attrs[count] = NULL;
382	power_zone->zone_attr_count = count;
383}
384
385static void powercap_release(struct device *dev)
386{
387	bool allocated;
388
389	if (dev->parent) {
390		struct powercap_zone *power_zone = to_powercap_zone(dev);
391
392		/* Store flag as the release() may free memory */
393		allocated = power_zone->allocated;
394		/* Remove id from parent idr struct */
395		idr_remove(power_zone->parent_idr, power_zone->id);
396		/* Destroy idrs allocated for this zone */
397		idr_destroy(&power_zone->idr);
398		kfree(power_zone->name);
399		kfree(power_zone->zone_dev_attrs);
400		kfree(power_zone->constraints);
401		if (power_zone->ops->release)
402			power_zone->ops->release(power_zone);
403		if (allocated)
404			kfree(power_zone);
405	} else {
406		struct powercap_control_type *control_type =
407						to_powercap_control_type(dev);
408
409		/* Store flag as the release() may free memory */
410		allocated = control_type->allocated;
411		idr_destroy(&control_type->idr);
412		mutex_destroy(&control_type->lock);
413		if (control_type->ops && control_type->ops->release)
414			control_type->ops->release(control_type);
415		if (allocated)
416			kfree(control_type);
417	}
418}
419
420static ssize_t enabled_show(struct device *dev,
421				struct device_attribute *attr,
422				char *buf)
423{
424	bool mode = true;
425
426	/* Default is enabled */
427	if (dev->parent) {
428		struct powercap_zone *power_zone = to_powercap_zone(dev);
429		if (power_zone->ops->get_enable)
430			if (power_zone->ops->get_enable(power_zone, &mode))
431				mode = false;
432	} else {
433		struct powercap_control_type *control_type =
434						to_powercap_control_type(dev);
435		if (control_type->ops && control_type->ops->get_enable)
436			if (control_type->ops->get_enable(control_type, &mode))
437				mode = false;
438	}
439
440	return sprintf(buf, "%d\n", mode);
441}
442
443static ssize_t enabled_store(struct device *dev,
444				struct device_attribute *attr,
445				const char *buf,  size_t len)
446{
447	bool mode;
448
449	if (strtobool(buf, &mode))
450		return -EINVAL;
451	if (dev->parent) {
452		struct powercap_zone *power_zone = to_powercap_zone(dev);
453		if (power_zone->ops->set_enable)
454			if (!power_zone->ops->set_enable(power_zone, mode))
455				return len;
456	} else {
457		struct powercap_control_type *control_type =
458						to_powercap_control_type(dev);
459		if (control_type->ops && control_type->ops->set_enable)
460			if (!control_type->ops->set_enable(control_type, mode))
461				return len;
462	}
463
464	return -ENOSYS;
465}
466
467static DEVICE_ATTR_RW(enabled);
468
469static struct attribute *powercap_attrs[] = {
470	&dev_attr_enabled.attr,
471	NULL,
472};
473ATTRIBUTE_GROUPS(powercap);
474
475static struct class powercap_class = {
476	.name = "powercap",
477	.dev_release = powercap_release,
478	.dev_groups = powercap_groups,
479};
480
481struct powercap_zone *powercap_register_zone(
482			struct powercap_zone *power_zone,
483			struct powercap_control_type *control_type,
484			const char *name,
485			struct powercap_zone *parent,
486			const struct powercap_zone_ops *ops,
487			int nr_constraints,
488			const struct powercap_zone_constraint_ops *const_ops)
489{
490	int result;
491	int nr_attrs;
492
493	if (!name || !control_type || !ops ||
494			nr_constraints > MAX_CONSTRAINTS_PER_ZONE ||
495			(!ops->get_energy_uj && !ops->get_power_uw) ||
496			!control_type_valid(control_type))
497		return ERR_PTR(-EINVAL);
498
499	if (power_zone) {
500		if (!ops->release)
501			return ERR_PTR(-EINVAL);
502		memset(power_zone, 0, sizeof(*power_zone));
503	} else {
504		power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL);
505		if (!power_zone)
506			return ERR_PTR(-ENOMEM);
507		power_zone->allocated = true;
508	}
509	power_zone->ops = ops;
510	power_zone->control_type_inst = control_type;
511	if (!parent) {
512		power_zone->dev.parent = &control_type->dev;
513		power_zone->parent_idr = &control_type->idr;
514	} else {
515		power_zone->dev.parent = &parent->dev;
516		power_zone->parent_idr = &parent->idr;
517	}
518	power_zone->dev.class = &powercap_class;
519
520	mutex_lock(&control_type->lock);
521	/* Using idr to get the unique id */
522	result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL);
523	if (result < 0)
524		goto err_idr_alloc;
525
526	power_zone->id = result;
527	idr_init(&power_zone->idr);
528	result = -ENOMEM;
529	power_zone->name = kstrdup(name, GFP_KERNEL);
530	if (!power_zone->name)
531		goto err_name_alloc;
532	dev_set_name(&power_zone->dev, "%s:%x",
533					dev_name(power_zone->dev.parent),
534					power_zone->id);
535	power_zone->constraints = kcalloc(nr_constraints,
536					  sizeof(*power_zone->constraints),
537					  GFP_KERNEL);
538	if (!power_zone->constraints)
539		goto err_const_alloc;
540
541	nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS +
542						POWERCAP_ZONE_MAX_ATTRS + 1;
543	power_zone->zone_dev_attrs = kcalloc(nr_attrs, sizeof(void *),
544					     GFP_KERNEL);
545	if (!power_zone->zone_dev_attrs)
546		goto err_attr_alloc;
547	create_power_zone_common_attributes(power_zone);
548	result = create_constraints(power_zone, nr_constraints, const_ops);
549	if (result)
550		goto err_dev_ret;
551
552	power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL;
553	power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs;
554	power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
555	power_zone->dev_attr_groups[1] = NULL;
556	power_zone->dev.groups = power_zone->dev_attr_groups;
 
 
 
557	result = device_register(&power_zone->dev);
558	if (result)
559		goto err_dev_ret;
 
 
 
 
560
561	control_type->nr_zones++;
562	mutex_unlock(&control_type->lock);
563
564	return power_zone;
565
566err_dev_ret:
567	kfree(power_zone->zone_dev_attrs);
568err_attr_alloc:
569	kfree(power_zone->constraints);
570err_const_alloc:
571	kfree(power_zone->name);
572err_name_alloc:
573	idr_remove(power_zone->parent_idr, power_zone->id);
574err_idr_alloc:
575	if (power_zone->allocated)
576		kfree(power_zone);
577	mutex_unlock(&control_type->lock);
578
579	return ERR_PTR(result);
580}
581EXPORT_SYMBOL_GPL(powercap_register_zone);
582
583int powercap_unregister_zone(struct powercap_control_type *control_type,
584				struct powercap_zone *power_zone)
585{
586	if (!power_zone || !control_type)
587		return -EINVAL;
588
589	mutex_lock(&control_type->lock);
590	control_type->nr_zones--;
591	mutex_unlock(&control_type->lock);
592
593	device_unregister(&power_zone->dev);
594
595	return 0;
596}
597EXPORT_SYMBOL_GPL(powercap_unregister_zone);
598
599struct powercap_control_type *powercap_register_control_type(
600				struct powercap_control_type *control_type,
601				const char *name,
602				const struct powercap_control_type_ops *ops)
603{
604	int result;
605
606	if (!name)
607		return ERR_PTR(-EINVAL);
608	if (control_type) {
609		if (!ops || !ops->release)
610			return ERR_PTR(-EINVAL);
611		memset(control_type, 0, sizeof(*control_type));
612	} else {
613		control_type = kzalloc(sizeof(*control_type), GFP_KERNEL);
614		if (!control_type)
615			return ERR_PTR(-ENOMEM);
616		control_type->allocated = true;
617	}
618	mutex_init(&control_type->lock);
619	control_type->ops = ops;
620	INIT_LIST_HEAD(&control_type->node);
621	control_type->dev.class = &powercap_class;
622	dev_set_name(&control_type->dev, "%s", name);
623	result = device_register(&control_type->dev);
624	if (result) {
625		if (control_type->allocated)
626			kfree(control_type);
627		return ERR_PTR(result);
628	}
629	idr_init(&control_type->idr);
630
631	mutex_lock(&powercap_cntrl_list_lock);
632	list_add_tail(&control_type->node, &powercap_cntrl_list);
633	mutex_unlock(&powercap_cntrl_list_lock);
634
635	return control_type;
636}
637EXPORT_SYMBOL_GPL(powercap_register_control_type);
638
639int powercap_unregister_control_type(struct powercap_control_type *control_type)
640{
641	struct powercap_control_type *pos = NULL;
642
643	if (control_type->nr_zones) {
644		dev_err(&control_type->dev, "Zones of this type still not freed\n");
645		return -EINVAL;
646	}
647	mutex_lock(&powercap_cntrl_list_lock);
648	list_for_each_entry(pos, &powercap_cntrl_list, node) {
649		if (pos == control_type) {
650			list_del(&control_type->node);
651			mutex_unlock(&powercap_cntrl_list_lock);
652			device_unregister(&control_type->dev);
653			return 0;
654		}
655	}
656	mutex_unlock(&powercap_cntrl_list_lock);
657
658	return -ENODEV;
659}
660EXPORT_SYMBOL_GPL(powercap_unregister_control_type);
661
662static int __init powercap_init(void)
663{
664	int result;
665
666	result = seed_constraint_attributes();
667	if (result)
668		return result;
669
670	return class_register(&powercap_class);
671}
672
673fs_initcall(powercap_init);
674
675MODULE_DESCRIPTION("PowerCap sysfs Driver");
676MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
677MODULE_LICENSE("GPL v2");