drivers/cpuidle/sysfs.c - kernel/skids - Git at Google

 /*
  * sysfs.c - sysfs support
  *
  * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
  *
  * This code is licenced under the GPL.
  */

 #include <linux/kernel.h>
 #include <linux/cpuidle.h>
 #include <linux/sysfs.h>
 #include <linux/slab.h>
 #include <linux/cpu.h>

 #include "cpuidle.h"

 static unsigned int sysfs_switch;
 static int __init cpuidle_sysfs_setup(char *unused)
 {
 	sysfs_switch = 1;
 	return 1;
 }
 __setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);

 static ssize_t show_available_governors(struct sysdev_class *class,
 					struct sysdev_class_attribute *attr,
 					char *buf)
 {
 	ssize_t i = 0;
 	struct cpuidle_governor *tmp;

 	mutex_lock(&cpuidle_lock);
 	list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
 		if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
 			goto out;
 		i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
 	}

 out:
 	i+= sprintf(&buf[i], "\n");
 	mutex_unlock(&cpuidle_lock);
 	return i;
 }

 static ssize_t show_current_driver(struct sysdev_class *class,
 				   struct sysdev_class_attribute *attr,
 				   char *buf)
 {
 	ssize_t ret;
 	struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();

 	spin_lock(&cpuidle_driver_lock);
 	if (cpuidle_driver)
 		ret = sprintf(buf, "%s\n", cpuidle_driver->name);
 	else
 		ret = sprintf(buf, "none\n");
 	spin_unlock(&cpuidle_driver_lock);

 	return ret;
 }

 static ssize_t show_current_governor(struct sysdev_class *class,
 				     struct sysdev_class_attribute *attr,
 				     char *buf)
 {
 	ssize_t ret;

 	mutex_lock(&cpuidle_lock);
 	if (cpuidle_curr_governor)
 		ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
 	else
 		ret = sprintf(buf, "none\n");
 	mutex_unlock(&cpuidle_lock);

 	return ret;
 }

 static ssize_t store_current_governor(struct sysdev_class *class,
 				      struct sysdev_class_attribute *attr,
 				      const char *buf, size_t count)
 {
 	char gov_name[CPUIDLE_NAME_LEN];
 	int ret = -EINVAL;
 	size_t len = count;
 	struct cpuidle_governor *gov;

 	if (!len || len >= sizeof(gov_name))
 		return -EINVAL;

 	memcpy(gov_name, buf, len);
 	gov_name[len] = '\0';
 	if (gov_name[len - 1] == '\n')
 		gov_name[--len] = '\0';

 	mutex_lock(&cpuidle_lock);

 	list_for_each_entry(gov, &cpuidle_governors, governor_list) {
 		if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
 			ret = cpuidle_switch_governor(gov);
 			break;
 		}
 	}

 	mutex_unlock(&cpuidle_lock);

 	if (ret)
 		return ret;
 	else
 		return count;
 }

 static SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
 static SYSDEV_CLASS_ATTR(current_governor_ro, 0444, show_current_governor,
 			 NULL);

 static struct attribute *cpuclass_default_attrs[] = {
 	&attr_current_driver.attr,
 	&attr_current_governor_ro.attr,
 	NULL
 };

 static SYSDEV_CLASS_ATTR(available_governors, 0444, show_available_governors,
 			 NULL);
 static SYSDEV_CLASS_ATTR(current_governor, 0644, show_current_governor,
 			 store_current_governor);

 static struct attribute *cpuclass_switch_attrs[] = {
 	&attr_available_governors.attr,
 	&attr_current_driver.attr,
 	&attr_current_governor.attr,
 	NULL
 };

 static struct attribute_group cpuclass_attr_group = {
 	.attrs = cpuclass_default_attrs,
 	.name = "cpuidle",
 };

 /**
  * cpuidle_add_class_sysfs - add CPU global sysfs attributes
  */
 int cpuidle_add_class_sysfs(struct sysdev_class *cls)
 {
 	if (sysfs_switch)
 		cpuclass_attr_group.attrs = cpuclass_switch_attrs;

 	return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
 }

 /**
  * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
  */
 void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
 {
 	sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
 }

 struct cpuidle_attr {
 	struct attribute attr;
 	ssize_t (*show)(struct cpuidle_device *, char *);
 	ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
 };

 #define define_one_ro(_name, show) \
 	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
 #define define_one_rw(_name, show, store) \
 	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)

 #define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
 #define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
 static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
 {
 	int ret = -EIO;
 	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
 	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);

 	if (cattr->show) {
 		mutex_lock(&cpuidle_lock);
 		ret = cattr->show(dev, buf);
 		mutex_unlock(&cpuidle_lock);
 	}
 	return ret;
 }

 static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
 		     const char * buf, size_t count)
 {
 	int ret = -EIO;
 	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
 	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);

 	if (cattr->store) {
 		mutex_lock(&cpuidle_lock);
 		ret = cattr->store(dev, buf, count);
 		mutex_unlock(&cpuidle_lock);
 	}
 	return ret;
 }

 static const struct sysfs_ops cpuidle_sysfs_ops = {
 	.show = cpuidle_show,
 	.store = cpuidle_store,
 };

 static void cpuidle_sysfs_release(struct kobject *kobj)
 {
 	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);

 	complete(&dev->kobj_unregister);
 }

 static struct kobj_type ktype_cpuidle = {
 	.sysfs_ops = &cpuidle_sysfs_ops,
 	.release = cpuidle_sysfs_release,
 };

 struct cpuidle_state_attr {
 	struct attribute attr;
 	ssize_t (*show)(struct cpuidle_state *, char *);
 	ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
 };

 #define define_one_state_ro(_name, show) \
 static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)

 #define define_show_state_function(_name) \
 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 { \
 	return sprintf(buf, "%u\n", state->_name);\
 }

 #define define_show_state_ull_function(_name) \
 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 { \
 	return sprintf(buf, "%llu\n", state->_name);\
 }

 #define define_show_state_str_function(_name) \
 static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
 { \
 	if (state->_name[0] == '\0')\
 		return sprintf(buf, "<null>\n");\
 	return sprintf(buf, "%s\n", state->_name);\
 }

 define_show_state_function(exit_latency)
 define_show_state_function(power_usage)
 define_show_state_ull_function(usage)
 define_show_state_ull_function(time)
 define_show_state_str_function(name)
 define_show_state_str_function(desc)

 define_one_state_ro(name, show_state_name);
 define_one_state_ro(desc, show_state_desc);
 define_one_state_ro(latency, show_state_exit_latency);
 define_one_state_ro(power, show_state_power_usage);
 define_one_state_ro(usage, show_state_usage);
 define_one_state_ro(time, show_state_time);

 static struct attribute *cpuidle_state_default_attrs[] = {
 	&attr_name.attr,
 	&attr_desc.attr,
 	&attr_latency.attr,
 	&attr_power.attr,
 	&attr_usage.attr,
 	&attr_time.attr,
 	NULL
 };

 #define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
 #define kobj_to_state(k) (kobj_to_state_obj(k)->state)
 #define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
 static ssize_t cpuidle_state_show(struct kobject * kobj,
 	struct attribute * attr ,char * buf)
 {
 	int ret = -EIO;
 	struct cpuidle_state *state = kobj_to_state(kobj);
 	struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);

 	if (cattr->show)
 		ret = cattr->show(state, buf);

 	return ret;
 }

 static const struct sysfs_ops cpuidle_state_sysfs_ops = {
 	.show = cpuidle_state_show,
 };

 static void cpuidle_state_sysfs_release(struct kobject *kobj)
 {
 	struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);

 	complete(&state_obj->kobj_unregister);
 }

 static struct kobj_type ktype_state_cpuidle = {
 	.sysfs_ops = &cpuidle_state_sysfs_ops,
 	.default_attrs = cpuidle_state_default_attrs,
 	.release = cpuidle_state_sysfs_release,
 };

 static void inline cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
 {
 	kobject_put(&device->kobjs[i]->kobj);
 	wait_for_completion(&device->kobjs[i]->kobj_unregister);
 	kfree(device->kobjs[i]);
 	device->kobjs[i] = NULL;
 }

 /**
  * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
  * @device: the target device
  */
 int cpuidle_add_state_sysfs(struct cpuidle_device *device)
 {
 	int i, ret = -ENOMEM;
 	struct cpuidle_state_kobj *kobj;

 	/* state statistics */
 	for (i = 0; i < device->state_count; i++) {
 		kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
 		if (!kobj)
 			goto error_state;
 		kobj->state = &device->states[i];
 		init_completion(&kobj->kobj_unregister);

 		ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
 					   "state%d", i);
 		if (ret) {
 			kfree(kobj);
 			goto error_state;
 		}
 		kobject_uevent(&kobj->kobj, KOBJ_ADD);
 		device->kobjs[i] = kobj;
 	}

 	return 0;

 error_state:
 	for (i = i - 1; i >= 0; i--)
 		cpuidle_free_state_kobj(device, i);
 	return ret;
 }

 /**
  * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
  * @device: the target device
  */
 void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
 {
 	int i;

 	for (i = 0; i < device->state_count; i++)
 		cpuidle_free_state_kobj(device, i);
 }

 /**
  * cpuidle_add_sysfs - creates a sysfs instance for the target device
  * @sysdev: the target device
  */
 int cpuidle_add_sysfs(struct sys_device *sysdev)
 {
 	int cpu = sysdev->id;
 	struct cpuidle_device *dev;
 	int error;

 	dev = per_cpu(cpuidle_devices, cpu);
 	error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
 				     "cpuidle");
 	if (!error)
 		kobject_uevent(&dev->kobj, KOBJ_ADD);
 	return error;
 }

 /**
  * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
  * @sysdev: the target device
  */
 void cpuidle_remove_sysfs(struct sys_device *sysdev)
 {
 	int cpu = sysdev->id;
 	struct cpuidle_device *dev;

 	dev = per_cpu(cpuidle_devices, cpu);
 	kobject_put(&dev->kobj);
 }
	/*
	* sysfs.c - sysfs support
	*
	* (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
	*
	* This code is licenced under the GPL.
	*/

	#include <linux/kernel.h>
	#include <linux/cpuidle.h>
	#include <linux/sysfs.h>
	#include <linux/slab.h>
	#include <linux/cpu.h>

	#include "cpuidle.h"

	static unsigned int sysfs_switch;
	static int __init cpuidle_sysfs_setup(char *unused)
	{
	sysfs_switch = 1;
	return 1;
	}
	__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);

	static ssize_t show_available_governors(struct sysdev_class *class,
	struct sysdev_class_attribute *attr,
	char *buf)
	{
	ssize_t i = 0;
	struct cpuidle_governor *tmp;

	mutex_lock(&cpuidle_lock);
	list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
	if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
	goto out;
	i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
	}

	out:
	i+= sprintf(&buf[i], "\n");
	mutex_unlock(&cpuidle_lock);
	return i;
	}

	static ssize_t show_current_driver(struct sysdev_class *class,
	struct sysdev_class_attribute *attr,
	char *buf)
	{
	ssize_t ret;
	struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver();

	spin_lock(&cpuidle_driver_lock);
	if (cpuidle_driver)
	ret = sprintf(buf, "%s\n", cpuidle_driver->name);
	else
	ret = sprintf(buf, "none\n");
	spin_unlock(&cpuidle_driver_lock);

	return ret;
	}

	static ssize_t show_current_governor(struct sysdev_class *class,
	struct sysdev_class_attribute *attr,
	char *buf)
	{
	ssize_t ret;

	mutex_lock(&cpuidle_lock);
	if (cpuidle_curr_governor)
	ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
	else
	ret = sprintf(buf, "none\n");
	mutex_unlock(&cpuidle_lock);

	return ret;
	}

	static ssize_t store_current_governor(struct sysdev_class *class,
	struct sysdev_class_attribute *attr,
	const char *buf, size_t count)
	{
	char gov_name[CPUIDLE_NAME_LEN];
	int ret = -EINVAL;
	size_t len = count;
	struct cpuidle_governor *gov;

	if (!len \|\| len >= sizeof(gov_name))
	return -EINVAL;

	memcpy(gov_name, buf, len);
	gov_name[len] = '\0';
	if (gov_name[len - 1] == '\n')
	gov_name[--len] = '\0';

	mutex_lock(&cpuidle_lock);

	list_for_each_entry(gov, &cpuidle_governors, governor_list) {
	if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
	ret = cpuidle_switch_governor(gov);
	break;
	}
	}

	mutex_unlock(&cpuidle_lock);

	if (ret)
	return ret;
	else
	return count;
	}

	static SYSDEV_CLASS_ATTR(current_driver, 0444, show_current_driver, NULL);
	static SYSDEV_CLASS_ATTR(current_governor_ro, 0444, show_current_governor,
	NULL);

	static struct attribute *cpuclass_default_attrs[] = {
	&attr_current_driver.attr,
	&attr_current_governor_ro.attr,
	NULL
	};

	static SYSDEV_CLASS_ATTR(available_governors, 0444, show_available_governors,
	NULL);
	static SYSDEV_CLASS_ATTR(current_governor, 0644, show_current_governor,
	store_current_governor);

	static struct attribute *cpuclass_switch_attrs[] = {
	&attr_available_governors.attr,
	&attr_current_driver.attr,
	&attr_current_governor.attr,
	NULL
	};

	static struct attribute_group cpuclass_attr_group = {
	.attrs = cpuclass_default_attrs,
	.name = "cpuidle",
	};

	/**
	* cpuidle_add_class_sysfs - add CPU global sysfs attributes
	*/
	int cpuidle_add_class_sysfs(struct sysdev_class *cls)
	{
	if (sysfs_switch)
	cpuclass_attr_group.attrs = cpuclass_switch_attrs;

	return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
	}

	/**
	* cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
	*/
	void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
	{
	sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
	}

	struct cpuidle_attr {
	struct attribute attr;
	ssize_t (show)(struct cpuidle_device , char *);
	ssize_t (store)(struct cpuidle_device , const char *, size_t count);
	};

	#define define_one_ro(_name, show) \
	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
	#define define_one_rw(_name, show, store) \
	static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)

	#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
	#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
	static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
	{
	int ret = -EIO;
	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);

	if (cattr->show) {
	mutex_lock(&cpuidle_lock);
	ret = cattr->show(dev, buf);
	mutex_unlock(&cpuidle_lock);
	}
	return ret;
	}

	static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
	const char * buf, size_t count)
	{
	int ret = -EIO;
	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
	struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);

	if (cattr->store) {
	mutex_lock(&cpuidle_lock);
	ret = cattr->store(dev, buf, count);
	mutex_unlock(&cpuidle_lock);
	}
	return ret;
	}

	static const struct sysfs_ops cpuidle_sysfs_ops = {
	.show = cpuidle_show,
	.store = cpuidle_store,
	};

	static void cpuidle_sysfs_release(struct kobject *kobj)
	{
	struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);

	complete(&dev->kobj_unregister);
	}

	static struct kobj_type ktype_cpuidle = {
	.sysfs_ops = &cpuidle_sysfs_ops,
	.release = cpuidle_sysfs_release,
	};

	struct cpuidle_state_attr {
	struct attribute attr;
	ssize_t (show)(struct cpuidle_state , char *);
	ssize_t (store)(struct cpuidle_state , const char *, size_t);
	};

	#define define_one_state_ro(_name, show) \
	static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)

	#define define_show_state_function(_name) \
	static ssize_t show_state_##_name(struct cpuidle_state state, char buf) \
	{ \
	return sprintf(buf, "%u\n", state->_name);\
	}

	#define define_show_state_ull_function(_name) \
	static ssize_t show_state_##_name(struct cpuidle_state state, char buf) \
	{ \
	return sprintf(buf, "%llu\n", state->_name);\
	}

	#define define_show_state_str_function(_name) \
	static ssize_t show_state_##_name(struct cpuidle_state state, char buf) \
	{ \
	if (state->_name[0] == '\0')\
	return sprintf(buf, "<null>\n");\
	return sprintf(buf, "%s\n", state->_name);\
	}

	define_show_state_function(exit_latency)
	define_show_state_function(power_usage)
	define_show_state_ull_function(usage)
	define_show_state_ull_function(time)
	define_show_state_str_function(name)
	define_show_state_str_function(desc)

	define_one_state_ro(name, show_state_name);
	define_one_state_ro(desc, show_state_desc);
	define_one_state_ro(latency, show_state_exit_latency);
	define_one_state_ro(power, show_state_power_usage);
	define_one_state_ro(usage, show_state_usage);
	define_one_state_ro(time, show_state_time);

	static struct attribute *cpuidle_state_default_attrs[] = {
	&attr_name.attr,
	&attr_desc.attr,
	&attr_latency.attr,
	&attr_power.attr,
	&attr_usage.attr,
	&attr_time.attr,
	NULL
	};

	#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
	#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
	#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
	static ssize_t cpuidle_state_show(struct kobject * kobj,
	struct attribute * attr ,char * buf)
	{
	int ret = -EIO;
	struct cpuidle_state *state = kobj_to_state(kobj);
	struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);

	if (cattr->show)
	ret = cattr->show(state, buf);

	return ret;
	}

	static const struct sysfs_ops cpuidle_state_sysfs_ops = {
	.show = cpuidle_state_show,
	};

	static void cpuidle_state_sysfs_release(struct kobject *kobj)
	{
	struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);

	complete(&state_obj->kobj_unregister);
	}

	static struct kobj_type ktype_state_cpuidle = {
	.sysfs_ops = &cpuidle_state_sysfs_ops,
	.default_attrs = cpuidle_state_default_attrs,
	.release = cpuidle_state_sysfs_release,
	};

	static void inline cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
	{
	kobject_put(&device->kobjs[i]->kobj);
	wait_for_completion(&device->kobjs[i]->kobj_unregister);
	kfree(device->kobjs[i]);
	device->kobjs[i] = NULL;
	}

	/**
	* cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
	* @device: the target device
	*/
	int cpuidle_add_state_sysfs(struct cpuidle_device *device)
	{
	int i, ret = -ENOMEM;
	struct cpuidle_state_kobj *kobj;

	/* state statistics */
	for (i = 0; i < device->state_count; i++) {
	kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
	if (!kobj)
	goto error_state;
	kobj->state = &device->states[i];
	init_completion(&kobj->kobj_unregister);

	ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj,
	"state%d", i);
	if (ret) {
	kfree(kobj);
	goto error_state;
	}
	kobject_uevent(&kobj->kobj, KOBJ_ADD);
	device->kobjs[i] = kobj;
	}

	return 0;

	error_state:
	for (i = i - 1; i >= 0; i--)
	cpuidle_free_state_kobj(device, i);
	return ret;
	}

	/**
	* cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
	* @device: the target device
	*/
	void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
	{
	int i;

	for (i = 0; i < device->state_count; i++)
	cpuidle_free_state_kobj(device, i);
	}

	/**
	* cpuidle_add_sysfs - creates a sysfs instance for the target device
	* @sysdev: the target device
	*/
	int cpuidle_add_sysfs(struct sys_device *sysdev)
	{
	int cpu = sysdev->id;
	struct cpuidle_device *dev;
	int error;

	dev = per_cpu(cpuidle_devices, cpu);
	error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &sysdev->kobj,
	"cpuidle");
	if (!error)
	kobject_uevent(&dev->kobj, KOBJ_ADD);
	return error;
	}

	/**
	* cpuidle_remove_sysfs - deletes a sysfs instance on the target device
	* @sysdev: the target device
	*/
	void cpuidle_remove_sysfs(struct sys_device *sysdev)
	{
	int cpu = sysdev->id;
	struct cpuidle_device *dev;

	dev = per_cpu(cpuidle_devices, cpu);
	kobject_put(&dev->kobj);
	}