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v3.1
  1/*
  2 * sysfs.c - sysfs support
  3 *
  4 * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
  5 *
  6 * This code is licenced under the GPL.
  7 */
  8
  9#include <linux/kernel.h>
 10#include <linux/cpuidle.h>
 11#include <linux/sysfs.h>
 12#include <linux/slab.h>
 13#include <linux/cpu.h>
 
 14
 15#include "cpuidle.h"
 16
 17static unsigned int sysfs_switch;
 18static int __init cpuidle_sysfs_setup(char *unused)
 19{
 20	sysfs_switch = 1;
 21	return 1;
 22}
 23__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
 24
 25static ssize_t show_available_governors(struct sysdev_class *class,
 26					struct sysdev_class_attribute *attr,
 27					char *buf)
 28{
 29	ssize_t i = 0;
 30	struct cpuidle_governor *tmp;
 31
 32	mutex_lock(&cpuidle_lock);
 33	list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
 34		if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
 35			goto out;
 36		i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
 37	}
 38
 39out:
 40	i+= sprintf(&buf[i], "\n");
 41	mutex_unlock(&cpuidle_lock);
 42	return i;
 43}
 44
 45static ssize_t show_current_driver(struct sysdev_class *class,
 46				   struct sysdev_class_attribute *attr,
 47				   char *buf)
 48{
 49	ssize_t ret;
 50	struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
 51
 52	spin_lock(&cpuidle_driver_lock);
 53	if (cpuidle_driver)
 54		ret = sprintf(buf, "%s\n", cpuidle_driver->name);
 55	else
 56		ret = sprintf(buf, "none\n");
 57	spin_unlock(&cpuidle_driver_lock);
 58
 59	return ret;
 60}
 61
 62static ssize_t show_current_governor(struct sysdev_class *class,
 63				     struct sysdev_class_attribute *attr,
 64				     char *buf)
 65{
 66	ssize_t ret;
 67
 68	mutex_lock(&cpuidle_lock);
 69	if (cpuidle_curr_governor)
 70		ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
 71	else
 72		ret = sprintf(buf, "none\n");
 73	mutex_unlock(&cpuidle_lock);
 74
 75	return ret;
 76}
 77
 78static ssize_t store_current_governor(struct sysdev_class *class,
 79				      struct sysdev_class_attribute *attr,
 80				      const char *buf, size_t count)
 81{
 82	char gov_name[CPUIDLE_NAME_LEN];
 83	int ret = -EINVAL;
 84	size_t len = count;
 85	struct cpuidle_governor *gov;
 86
 87	if (!len || len >= sizeof(gov_name))
 88		return -EINVAL;
 89
 90	memcpy(gov_name, buf, len);
 91	gov_name[len] = '\0';
 92	if (gov_name[len - 1] == '\n')
 93		gov_name[--len] = '\0';
 94
 95	mutex_lock(&cpuidle_lock);
 96
 97	list_for_each_entry(gov, &cpuidle_governors, governor_list) {
 98		if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
 99			ret = cpuidle_switch_governor(gov);
100			break;
101		}
102	}
103
104	mutex_unlock(&cpuidle_lock);
105
106	if (ret)
107		return ret;
108	else
109		return count;
110}
111
112static SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
113static SYSDEV_CLASS_ATTR(current_governor_ro, 0444, show_current_governor,
114			 NULL);
115
116static struct attribute *cpuclass_default_attrs[] = {
117	&attr_current_driver.attr,
118	&attr_current_governor_ro.attr,
119	NULL
120};
121
122static SYSDEV_CLASS_ATTR(available_governors, 0444, show_available_governors,
123			 NULL);
124static SYSDEV_CLASS_ATTR(current_governor, 0644, show_current_governor,
125			 store_current_governor);
126
127static struct attribute *cpuclass_switch_attrs[] = {
128	&attr_available_governors.attr,
129	&attr_current_driver.attr,
130	&attr_current_governor.attr,
131	NULL
132};
133
134static struct attribute_group cpuclass_attr_group = {
135	.attrs = cpuclass_default_attrs,
136	.name = "cpuidle",
137};
138
139/**
140 * cpuidle_add_class_sysfs - add CPU global sysfs attributes
141 */
142int cpuidle_add_class_sysfs(struct sysdev_class *cls)
143{
144	if (sysfs_switch)
145		cpuclass_attr_group.attrs = cpuclass_switch_attrs;
146
147	return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
148}
149
150/**
151 * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
152 */
153void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
154{
155	sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
156}
157
158struct cpuidle_attr {
159	struct attribute attr;
160	ssize_t (*show)(struct cpuidle_device *, char *);
161	ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
162};
163
164#define define_one_ro(_name, show) \
165	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
166#define define_one_rw(_name, show, store) \
167	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
168
169#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
170#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
171static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
172{
173	int ret = -EIO;
174	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
175	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
176
177	if (cattr->show) {
178		mutex_lock(&cpuidle_lock);
179		ret = cattr->show(dev, buf);
180		mutex_unlock(&cpuidle_lock);
181	}
182	return ret;
183}
184
185static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
186		     const char * buf, size_t count)
187{
188	int ret = -EIO;
189	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
190	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
191
192	if (cattr->store) {
193		mutex_lock(&cpuidle_lock);
194		ret = cattr->store(dev, buf, count);
195		mutex_unlock(&cpuidle_lock);
196	}
197	return ret;
198}
199
200static const struct sysfs_ops cpuidle_sysfs_ops = {
201	.show = cpuidle_show,
202	.store = cpuidle_store,
203};
204
205static void cpuidle_sysfs_release(struct kobject *kobj)
206{
207	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
208
209	complete(&dev->kobj_unregister);
210}
211
212static struct kobj_type ktype_cpuidle = {
213	.sysfs_ops = &cpuidle_sysfs_ops,
214	.release = cpuidle_sysfs_release,
215};
216
217struct cpuidle_state_attr {
218	struct attribute attr;
219	ssize_t (*show)(struct cpuidle_state *, char *);
 
220	ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
221};
222
223#define define_one_state_ro(_name, show) \
224static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
225
 
 
 
226#define define_show_state_function(_name) \
227static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 
228{ \
229	return sprintf(buf, "%u\n", state->_name);\
230}
231
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
232#define define_show_state_ull_function(_name) \
233static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 
234{ \
235	return sprintf(buf, "%llu\n", state->_name);\
236}
237
238#define define_show_state_str_function(_name) \
239static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 
240{ \
241	if (state->_name[0] == '\0')\
242		return sprintf(buf, "<null>\n");\
243	return sprintf(buf, "%s\n", state->_name);\
244}
245
246define_show_state_function(exit_latency)
247define_show_state_function(power_usage)
248define_show_state_ull_function(usage)
249define_show_state_ull_function(time)
250define_show_state_str_function(name)
251define_show_state_str_function(desc)
 
 
252
253define_one_state_ro(name, show_state_name);
254define_one_state_ro(desc, show_state_desc);
255define_one_state_ro(latency, show_state_exit_latency);
256define_one_state_ro(power, show_state_power_usage);
257define_one_state_ro(usage, show_state_usage);
258define_one_state_ro(time, show_state_time);
 
259
260static struct attribute *cpuidle_state_default_attrs[] = {
261	&attr_name.attr,
262	&attr_desc.attr,
263	&attr_latency.attr,
264	&attr_power.attr,
265	&attr_usage.attr,
266	&attr_time.attr,
 
267	NULL
268};
269
270#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
271#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
 
272#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
273static ssize_t cpuidle_state_show(struct kobject * kobj,
274	struct attribute * attr ,char * buf)
275{
276	int ret = -EIO;
277	struct cpuidle_state *state = kobj_to_state(kobj);
 
278	struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
279
280	if (cattr->show)
281		ret = cattr->show(state, buf);
 
 
 
 
 
 
 
 
 
 
 
 
 
282
283	return ret;
284}
285
286static const struct sysfs_ops cpuidle_state_sysfs_ops = {
287	.show = cpuidle_state_show,
 
288};
289
290static void cpuidle_state_sysfs_release(struct kobject *kobj)
291{
292	struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
293
294	complete(&state_obj->kobj_unregister);
295}
296
297static struct kobj_type ktype_state_cpuidle = {
298	.sysfs_ops = &cpuidle_state_sysfs_ops,
299	.default_attrs = cpuidle_state_default_attrs,
300	.release = cpuidle_state_sysfs_release,
301};
302
303static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
304{
305	kobject_put(&device->kobjs[i]->kobj);
306	wait_for_completion(&device->kobjs[i]->kobj_unregister);
307	kfree(device->kobjs[i]);
308	device->kobjs[i] = NULL;
309}
310
311/**
312 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
313 * @device: the target device
314 */
315int cpuidle_add_state_sysfs(struct cpuidle_device *device)
316{
317	int i, ret = -ENOMEM;
318	struct cpuidle_state_kobj *kobj;
 
319
320	/* state statistics */
321	for (i = 0; i < device->state_count; i++) {
322		kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
323		if (!kobj)
324			goto error_state;
325		kobj->state = &device->states[i];
 
326		init_completion(&kobj->kobj_unregister);
327
328		ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
329					   "state%d", i);
330		if (ret) {
331			kfree(kobj);
332			goto error_state;
333		}
334		kobject_uevent(&kobj->kobj, KOBJ_ADD);
335		device->kobjs[i] = kobj;
336	}
337
338	return 0;
339
340error_state:
341	for (i = i - 1; i >= 0; i--)
342		cpuidle_free_state_kobj(device, i);
343	return ret;
344}
345
346/**
347 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
348 * @device: the target device
349 */
350void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
351{
352	int i;
353
354	for (i = 0; i < device->state_count; i++)
355		cpuidle_free_state_kobj(device, i);
356}
357
358/**
359 * cpuidle_add_sysfs - creates a sysfs instance for the target device
360 * @sysdev: the target device
361 */
362int cpuidle_add_sysfs(struct sys_device *sysdev)
363{
364	int cpu = sysdev->id;
365	struct cpuidle_device *dev;
366	int error;
367
368	dev = per_cpu(cpuidle_devices, cpu);
369	error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
370				     "cpuidle");
371	if (!error)
372		kobject_uevent(&dev->kobj, KOBJ_ADD);
373	return error;
374}
375
376/**
377 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
378 * @sysdev: the target device
379 */
380void cpuidle_remove_sysfs(struct sys_device *sysdev)
381{
382	int cpu = sysdev->id;
383	struct cpuidle_device *dev;
384
385	dev = per_cpu(cpuidle_devices, cpu);
386	kobject_put(&dev->kobj);
387}
v3.5.6
  1/*
  2 * sysfs.c - sysfs support
  3 *
  4 * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
  5 *
  6 * This code is licenced under the GPL.
  7 */
  8
  9#include <linux/kernel.h>
 10#include <linux/cpuidle.h>
 11#include <linux/sysfs.h>
 12#include <linux/slab.h>
 13#include <linux/cpu.h>
 14#include <linux/capability.h>
 15
 16#include "cpuidle.h"
 17
 18static unsigned int sysfs_switch;
 19static int __init cpuidle_sysfs_setup(char *unused)
 20{
 21	sysfs_switch = 1;
 22	return 1;
 23}
 24__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
 25
 26static ssize_t show_available_governors(struct device *dev,
 27					struct device_attribute *attr,
 28					char *buf)
 29{
 30	ssize_t i = 0;
 31	struct cpuidle_governor *tmp;
 32
 33	mutex_lock(&cpuidle_lock);
 34	list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
 35		if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
 36			goto out;
 37		i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
 38	}
 39
 40out:
 41	i+= sprintf(&buf[i], "\n");
 42	mutex_unlock(&cpuidle_lock);
 43	return i;
 44}
 45
 46static ssize_t show_current_driver(struct device *dev,
 47				   struct device_attribute *attr,
 48				   char *buf)
 49{
 50	ssize_t ret;
 51	struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();
 52
 53	spin_lock(&cpuidle_driver_lock);
 54	if (cpuidle_driver)
 55		ret = sprintf(buf, "%s\n", cpuidle_driver->name);
 56	else
 57		ret = sprintf(buf, "none\n");
 58	spin_unlock(&cpuidle_driver_lock);
 59
 60	return ret;
 61}
 62
 63static ssize_t show_current_governor(struct device *dev,
 64				     struct device_attribute *attr,
 65				     char *buf)
 66{
 67	ssize_t ret;
 68
 69	mutex_lock(&cpuidle_lock);
 70	if (cpuidle_curr_governor)
 71		ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
 72	else
 73		ret = sprintf(buf, "none\n");
 74	mutex_unlock(&cpuidle_lock);
 75
 76	return ret;
 77}
 78
 79static ssize_t store_current_governor(struct device *dev,
 80				      struct device_attribute *attr,
 81				      const char *buf, size_t count)
 82{
 83	char gov_name[CPUIDLE_NAME_LEN];
 84	int ret = -EINVAL;
 85	size_t len = count;
 86	struct cpuidle_governor *gov;
 87
 88	if (!len || len >= sizeof(gov_name))
 89		return -EINVAL;
 90
 91	memcpy(gov_name, buf, len);
 92	gov_name[len] = '\0';
 93	if (gov_name[len - 1] == '\n')
 94		gov_name[--len] = '\0';
 95
 96	mutex_lock(&cpuidle_lock);
 97
 98	list_for_each_entry(gov, &cpuidle_governors, governor_list) {
 99		if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
100			ret = cpuidle_switch_governor(gov);
101			break;
102		}
103	}
104
105	mutex_unlock(&cpuidle_lock);
106
107	if (ret)
108		return ret;
109	else
110		return count;
111}
112
113static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL);
114static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
115
116static struct attribute *cpuidle_default_attrs[] = {
117	&dev_attr_current_driver.attr,
118	&dev_attr_current_governor_ro.attr,
 
119	NULL
120};
121
122static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL);
123static DEVICE_ATTR(current_governor, 0644, show_current_governor,
124		   store_current_governor);
125
126static struct attribute *cpuidle_switch_attrs[] = {
127	&dev_attr_available_governors.attr,
128	&dev_attr_current_driver.attr,
129	&dev_attr_current_governor.attr,
 
130	NULL
131};
132
133static struct attribute_group cpuidle_attr_group = {
134	.attrs = cpuidle_default_attrs,
135	.name = "cpuidle",
136};
137
138/**
139 * cpuidle_add_interface - add CPU global sysfs attributes
140 */
141int cpuidle_add_interface(struct device *dev)
142{
143	if (sysfs_switch)
144		cpuidle_attr_group.attrs = cpuidle_switch_attrs;
145
146	return sysfs_create_group(&dev->kobj, &cpuidle_attr_group);
147}
148
149/**
150 * cpuidle_remove_interface - remove CPU global sysfs attributes
151 */
152void cpuidle_remove_interface(struct device *dev)
153{
154	sysfs_remove_group(&dev->kobj, &cpuidle_attr_group);
155}
156
157struct cpuidle_attr {
158	struct attribute attr;
159	ssize_t (*show)(struct cpuidle_device *, char *);
160	ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
161};
162
163#define define_one_ro(_name, show) \
164	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
165#define define_one_rw(_name, show, store) \
166	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
167
168#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
169#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
170static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
171{
172	int ret = -EIO;
173	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
174	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
175
176	if (cattr->show) {
177		mutex_lock(&cpuidle_lock);
178		ret = cattr->show(dev, buf);
179		mutex_unlock(&cpuidle_lock);
180	}
181	return ret;
182}
183
184static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
185		     const char * buf, size_t count)
186{
187	int ret = -EIO;
188	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
189	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
190
191	if (cattr->store) {
192		mutex_lock(&cpuidle_lock);
193		ret = cattr->store(dev, buf, count);
194		mutex_unlock(&cpuidle_lock);
195	}
196	return ret;
197}
198
199static const struct sysfs_ops cpuidle_sysfs_ops = {
200	.show = cpuidle_show,
201	.store = cpuidle_store,
202};
203
204static void cpuidle_sysfs_release(struct kobject *kobj)
205{
206	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
207
208	complete(&dev->kobj_unregister);
209}
210
211static struct kobj_type ktype_cpuidle = {
212	.sysfs_ops = &cpuidle_sysfs_ops,
213	.release = cpuidle_sysfs_release,
214};
215
216struct cpuidle_state_attr {
217	struct attribute attr;
218	ssize_t (*show)(struct cpuidle_state *, \
219					struct cpuidle_state_usage *, char *);
220	ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
221};
222
223#define define_one_state_ro(_name, show) \
224static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
225
226#define define_one_state_rw(_name, show, store) \
227static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0644, show, store)
228
229#define define_show_state_function(_name) \
230static ssize_t show_state_##_name(struct cpuidle_state *state, \
231			 struct cpuidle_state_usage *state_usage, char *buf) \
232{ \
233	return sprintf(buf, "%u\n", state->_name);\
234}
235
236#define define_store_state_function(_name) \
237static ssize_t store_state_##_name(struct cpuidle_state *state, \
238		const char *buf, size_t size) \
239{ \
240	long value; \
241	int err; \
242	if (!capable(CAP_SYS_ADMIN)) \
243		return -EPERM; \
244	err = kstrtol(buf, 0, &value); \
245	if (err) \
246		return err; \
247	if (value) \
248		state->disable = 1; \
249	else \
250		state->disable = 0; \
251	return size; \
252}
253
254#define define_show_state_ull_function(_name) \
255static ssize_t show_state_##_name(struct cpuidle_state *state, \
256			struct cpuidle_state_usage *state_usage, char *buf) \
257{ \
258	return sprintf(buf, "%llu\n", state_usage->_name);\
259}
260
261#define define_show_state_str_function(_name) \
262static ssize_t show_state_##_name(struct cpuidle_state *state, \
263			struct cpuidle_state_usage *state_usage, char *buf) \
264{ \
265	if (state->_name[0] == '\0')\
266		return sprintf(buf, "<null>\n");\
267	return sprintf(buf, "%s\n", state->_name);\
268}
269
270define_show_state_function(exit_latency)
271define_show_state_function(power_usage)
272define_show_state_ull_function(usage)
273define_show_state_ull_function(time)
274define_show_state_str_function(name)
275define_show_state_str_function(desc)
276define_show_state_function(disable)
277define_store_state_function(disable)
278
279define_one_state_ro(name, show_state_name);
280define_one_state_ro(desc, show_state_desc);
281define_one_state_ro(latency, show_state_exit_latency);
282define_one_state_ro(power, show_state_power_usage);
283define_one_state_ro(usage, show_state_usage);
284define_one_state_ro(time, show_state_time);
285define_one_state_rw(disable, show_state_disable, store_state_disable);
286
287static struct attribute *cpuidle_state_default_attrs[] = {
288	&attr_name.attr,
289	&attr_desc.attr,
290	&attr_latency.attr,
291	&attr_power.attr,
292	&attr_usage.attr,
293	&attr_time.attr,
294	&attr_disable.attr,
295	NULL
296};
297
298#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
299#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
300#define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage)
301#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
302static ssize_t cpuidle_state_show(struct kobject * kobj,
303	struct attribute * attr ,char * buf)
304{
305	int ret = -EIO;
306	struct cpuidle_state *state = kobj_to_state(kobj);
307	struct cpuidle_state_usage *state_usage = kobj_to_state_usage(kobj);
308	struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
309
310	if (cattr->show)
311		ret = cattr->show(state, state_usage, buf);
312
313	return ret;
314}
315
316static ssize_t cpuidle_state_store(struct kobject *kobj,
317	struct attribute *attr, const char *buf, size_t size)
318{
319	int ret = -EIO;
320	struct cpuidle_state *state = kobj_to_state(kobj);
321	struct cpuidle_state_attr *cattr = attr_to_stateattr(attr);
322
323	if (cattr->store)
324		ret = cattr->store(state, buf, size);
325
326	return ret;
327}
328
329static const struct sysfs_ops cpuidle_state_sysfs_ops = {
330	.show = cpuidle_state_show,
331	.store = cpuidle_state_store,
332};
333
334static void cpuidle_state_sysfs_release(struct kobject *kobj)
335{
336	struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
337
338	complete(&state_obj->kobj_unregister);
339}
340
341static struct kobj_type ktype_state_cpuidle = {
342	.sysfs_ops = &cpuidle_state_sysfs_ops,
343	.default_attrs = cpuidle_state_default_attrs,
344	.release = cpuidle_state_sysfs_release,
345};
346
347static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
348{
349	kobject_put(&device->kobjs[i]->kobj);
350	wait_for_completion(&device->kobjs[i]->kobj_unregister);
351	kfree(device->kobjs[i]);
352	device->kobjs[i] = NULL;
353}
354
355/**
356 * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
357 * @device: the target device
358 */
359int cpuidle_add_state_sysfs(struct cpuidle_device *device)
360{
361	int i, ret = -ENOMEM;
362	struct cpuidle_state_kobj *kobj;
363	struct cpuidle_driver *drv = cpuidle_get_driver();
364
365	/* state statistics */
366	for (i = 0; i < device->state_count; i++) {
367		kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
368		if (!kobj)
369			goto error_state;
370		kobj->state = &drv->states[i];
371		kobj->state_usage = &device->states_usage[i];
372		init_completion(&kobj->kobj_unregister);
373
374		ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
375					   "state%d", i);
376		if (ret) {
377			kfree(kobj);
378			goto error_state;
379		}
380		kobject_uevent(&kobj->kobj, KOBJ_ADD);
381		device->kobjs[i] = kobj;
382	}
383
384	return 0;
385
386error_state:
387	for (i = i - 1; i >= 0; i--)
388		cpuidle_free_state_kobj(device, i);
389	return ret;
390}
391
392/**
393 * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
394 * @device: the target device
395 */
396void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
397{
398	int i;
399
400	for (i = 0; i < device->state_count; i++)
401		cpuidle_free_state_kobj(device, i);
402}
403
404/**
405 * cpuidle_add_sysfs - creates a sysfs instance for the target device
406 * @dev: the target device
407 */
408int cpuidle_add_sysfs(struct device *cpu_dev)
409{
410	int cpu = cpu_dev->id;
411	struct cpuidle_device *dev;
412	int error;
413
414	dev = per_cpu(cpuidle_devices, cpu);
415	error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &cpu_dev->kobj,
416				     "cpuidle");
417	if (!error)
418		kobject_uevent(&dev->kobj, KOBJ_ADD);
419	return error;
420}
421
422/**
423 * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
424 * @dev: the target device
425 */
426void cpuidle_remove_sysfs(struct device *cpu_dev)
427{
428	int cpu = cpu_dev->id;
429	struct cpuidle_device *dev;
430
431	dev = per_cpu(cpuidle_devices, cpu);
432	kobject_put(&dev->kobj);
433}