/*
   * drivers/base/power/sysfs.c - sysfs entries for device PM
   */
  
  #include <linux/device.h>
  #include <linux/string.h>
  #include <linux/export.h>
  #include <linux/pm_qos.h>
  #include <linux/pm_runtime.h>
  #include <linux/atomic.h>
  #include <linux/jiffies.h>
  #include "power.h"
  
  /*
   *	control - Report/change current runtime PM setting of the device
   *
   *	Runtime power management of a device can be blocked with the help of
   *	this attribute.  All devices have one of the following two values for
   *	the power/control file:
   *
   *	 + "auto
  " to allow the device to be power managed at run time;
   *	 + "on
  " to prevent the device from being power managed at run time;
   *
   *	The default for all devices is "auto", which means that devices may be
   *	subject to automatic power management, depending on their drivers.
   *	Changing this attribute to "on" prevents the driver from power managing
   *	the device at run time.  Doing that while the device is suspended causes
   *	it to be woken up.
   *
   *	wakeup - Report/change current wakeup option for device
   *
   *	Some devices support "wakeup" events, which are hardware signals
   *	used to activate devices from suspended or low power states.  Such
   *	devices have one of three values for the sysfs power/wakeup file:
   *
   *	 + "enabled
  " to issue the events;
   *	 + "disabled
  " not to do so; or
   *	 + "
  " for temporary or permanent inability to issue wakeup.
   *
   *	(For example, unconfigured USB devices can't issue wakeups.)
   *
   *	Familiar examples of devices that can issue wakeup events include
   *	keyboards and mice (both PS2 and USB styles), power buttons, modems,
   *	"Wake-On-LAN" Ethernet links, GPIO lines, and more.  Some events
   *	will wake the entire system from a suspend state; others may just
   *	wake up the device (if the system as a whole is already active).
   *	Some wakeup events use normal IRQ lines; other use special out
   *	of band signaling.
   *
   *	It is the responsibility of device drivers to enable (or disable)
   *	wakeup signaling as part of changing device power states, respecting
   *	the policy choices provided through the driver model.
   *
   *	Devices may not be able to generate wakeup events from all power
   *	states.  Also, the events may be ignored in some configurations;
   *	for example, they might need help from other devices that aren't
   *	active, or which may have wakeup disabled.  Some drivers rely on
   *	wakeup events internally (unless they are disabled), keeping
   *	their hardware in low power modes whenever they're unused.  This
   *	saves runtime power, without requiring system-wide sleep states.
   *
   *	async - Report/change current async suspend setting for the device
   *
   *	Asynchronous suspend and resume of the device during system-wide power
   *	state transitions can be enabled by writing "enabled" to this file.
   *	Analogously, if "disabled" is written to this file, the device will be
   *	suspended and resumed synchronously.
   *
   *	All devices have one of the following two values for power/async:
   *
   *	 + "enabled
  " to permit the asynchronous suspend/resume of the device;
   *	 + "disabled
  " to forbid it;
   *
   *	NOTE: It generally is unsafe to permit the asynchronous suspend/resume
   *	of a device unless it is certain that all of the PM dependencies of the
   *	device are known to the PM core.  However, for some devices this
   *	attribute is set to "enabled" by bus type code or device drivers and in
   *	that cases it should be safe to leave the default value.
   *
   *	autosuspend_delay_ms - Report/change a device's autosuspend_delay value
   *
   *	Some drivers don't want to carry out a runtime suspend as soon as a
   *	device becomes idle; they want it always to remain idle for some period
   *	of time before suspending it.  This period is the autosuspend_delay
   *	value (expressed in milliseconds) and it can be controlled by the user.
   *	If the value is negative then the device will never be runtime
   *	suspended.
   *
   *	NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
   *	value are used only if the driver calls pm_runtime_use_autosuspend().
   *
   *	wakeup_count - Report the number of wakeup events related to the device
   */
  
  static const char enabled[] = "enabled";
  static const char disabled[] = "disabled";
  
  const char power_group_name[] = "power";
  EXPORT_SYMBOL_GPL(power_group_name);
  
  #ifdef CONFIG_PM_RUNTIME
  static const char ctrl_auto[] = "auto";
  static const char ctrl_on[] = "on";
  
  static ssize_t control_show(struct device *dev, struct device_attribute *attr,
  			    char *buf)
  {
  	return sprintf(buf, "%s
  ",
  				dev->power.runtime_auto ? ctrl_auto : ctrl_on);
  }
  
  static ssize_t control_store(struct device * dev, struct device_attribute *attr,
  			     const char * buf, size_t n)
  {
  	char *cp;
  	int len = n;
  
  	cp = memchr(buf, '
  ', n);
  	if (cp)
  		len = cp - buf;
  	device_lock(dev);
  	if (len == sizeof ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0)
  		pm_runtime_allow(dev);
  	else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0)
  		pm_runtime_forbid(dev);
  	else
  		n = -EINVAL;
  	device_unlock(dev);
  	return n;
  }
  
  static DEVICE_ATTR(control, 0644, control_show, control_store);
  
  static ssize_t rtpm_active_time_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	int ret;
  	spin_lock_irq(&dev->power.lock);
  	update_pm_runtime_accounting(dev);
  	ret = sprintf(buf, "%i
  ", jiffies_to_msecs(dev->power.active_jiffies));
  	spin_unlock_irq(&dev->power.lock);
  	return ret;
  }
  
  static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL);
  
  static ssize_t rtpm_suspended_time_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	int ret;
  	spin_lock_irq(&dev->power.lock);
  	update_pm_runtime_accounting(dev);
  	ret = sprintf(buf, "%i
  ",
  		jiffies_to_msecs(dev->power.suspended_jiffies));
  	spin_unlock_irq(&dev->power.lock);
  	return ret;
  }
  
  static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL);
  
  static ssize_t rtpm_status_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	const char *p;
  
  	if (dev->power.runtime_error) {
  		p = "error
  ";
  	} else if (dev->power.disable_depth) {
  		p = "unsupported
  ";
  	} else {
  		switch (dev->power.runtime_status) {
  		case RPM_SUSPENDED:
  			p = "suspended
  ";
  			break;
  		case RPM_SUSPENDING:
  			p = "suspending
  ";
  			break;
  		case RPM_RESUMING:
  			p = "resuming
  ";
  			break;
  		case RPM_ACTIVE:
  			p = "active
  ";
  			break;
  		default:
  			return -EIO;
  		}
  	}
  	return sprintf(buf, p);
  }
  
  static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL);
  
  static ssize_t autosuspend_delay_ms_show(struct device *dev,
  		struct device_attribute *attr, char *buf)
  {
  	if (!dev->power.use_autosuspend)
  		return -EIO;
  	return sprintf(buf, "%d
  ", dev->power.autosuspend_delay);
  }
  
  static ssize_t autosuspend_delay_ms_store(struct device *dev,
  		struct device_attribute *attr, const char *buf, size_t n)
  {
  	long delay;
  
  	if (!dev->power.use_autosuspend)
  		return -EIO;
  
  	if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
  		return -EINVAL;
  
  	device_lock(dev);
  	pm_runtime_set_autosuspend_delay(dev, delay);
  	device_unlock(dev);
  	return n;
  }
  
  static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
  		autosuspend_delay_ms_store);
  
  static ssize_t pm_qos_latency_show(struct device *dev,
  				   struct device_attribute *attr, char *buf)
  {
  	return sprintf(buf, "%d
  ", dev_pm_qos_requested_latency(dev));
  }
  
  static ssize_t pm_qos_latency_store(struct device *dev,
  				    struct device_attribute *attr,
  				    const char *buf, size_t n)
  {
  	s32 value;
  	int ret;
  
  	if (kstrtos32(buf, 0, &value))
  		return -EINVAL;
  
  	if (value < 0)
  		return -EINVAL;
  
  	ret = dev_pm_qos_update_request(dev->power.qos->latency_req, value);
  	return ret < 0 ? ret : n;
  }
  
  static DEVICE_ATTR(pm_qos_resume_latency_us, 0644,
  		   pm_qos_latency_show, pm_qos_latency_store);
  
  static ssize_t pm_qos_no_power_off_show(struct device *dev,
  					struct device_attribute *attr,
  					char *buf)
  {
  	return sprintf(buf, "%d
  ", !!(dev_pm_qos_requested_flags(dev)
  					& PM_QOS_FLAG_NO_POWER_OFF));
  }
  
  static ssize_t pm_qos_no_power_off_store(struct device *dev,
  					 struct device_attribute *attr,
  					 const char *buf, size_t n)
  {
  	int ret;
  
  	if (kstrtoint(buf, 0, &ret))
  		return -EINVAL;
  
  	if (ret != 0 && ret != 1)
  		return -EINVAL;
  
  	ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
  	return ret < 0 ? ret : n;
  }
  
  static DEVICE_ATTR(pm_qos_no_power_off, 0644,
  		   pm_qos_no_power_off_show, pm_qos_no_power_off_store);
  
  static ssize_t pm_qos_remote_wakeup_show(struct device *dev,
  					 struct device_attribute *attr,
  					 char *buf)
  {
  	return sprintf(buf, "%d
  ", !!(dev_pm_qos_requested_flags(dev)
  					& PM_QOS_FLAG_REMOTE_WAKEUP));
  }
  
  static ssize_t pm_qos_remote_wakeup_store(struct device *dev,
  					  struct device_attribute *attr,
  					  const char *buf, size_t n)
  {
  	int ret;
  
  	if (kstrtoint(buf, 0, &ret))
  		return -EINVAL;
  
  	if (ret != 0 && ret != 1)
  		return -EINVAL;
  
  	ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP, ret);
  	return ret < 0 ? ret : n;
  }
  
  static DEVICE_ATTR(pm_qos_remote_wakeup, 0644,
  		   pm_qos_remote_wakeup_show, pm_qos_remote_wakeup_store);
  #endif /* CONFIG_PM_RUNTIME */
  
  #ifdef CONFIG_PM_SLEEP
  static ssize_t
  wake_show(struct device * dev, struct device_attribute *attr, char * buf)
  {
  	return sprintf(buf, "%s
  ", device_can_wakeup(dev)
  		? (device_may_wakeup(dev) ? enabled : disabled)
  		: "");
  }
  
  static ssize_t
  wake_store(struct device * dev, struct device_attribute *attr,
  	const char * buf, size_t n)
  {
  	char *cp;
  	int len = n;
  
  	if (!device_can_wakeup(dev))
  		return -EINVAL;
  
  	cp = memchr(buf, '
  ', n);
  	if (cp)
  		len = cp - buf;
  	if (len == sizeof enabled - 1
  			&& strncmp(buf, enabled, sizeof enabled - 1) == 0)
  		device_set_wakeup_enable(dev, 1);
  	else if (len == sizeof disabled - 1
  			&& strncmp(buf, disabled, sizeof disabled - 1) == 0)
  		device_set_wakeup_enable(dev, 0);
  	else
  		return -EINVAL;
  	return n;
  }
  
  static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
  
  static ssize_t wakeup_count_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	unsigned long count = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		count = dev->power.wakeup->event_count;
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lu
  ", count) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
  
  static ssize_t wakeup_active_count_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	unsigned long count = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		count = dev->power.wakeup->active_count;
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lu
  ", count) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
  
  static ssize_t wakeup_abort_count_show(struct device *dev,
  					struct device_attribute *attr,
  					char *buf)
  {
  	unsigned long count = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		count = dev->power.wakeup->wakeup_count;
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lu
  ", count) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_abort_count, 0444, wakeup_abort_count_show, NULL);
  
  static ssize_t wakeup_expire_count_show(struct device *dev,
  					struct device_attribute *attr,
  					char *buf)
  {
  	unsigned long count = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		count = dev->power.wakeup->expire_count;
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lu
  ", count) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_expire_count, 0444, wakeup_expire_count_show, NULL);
  
  static ssize_t wakeup_active_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	unsigned int active = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		active = dev->power.wakeup->active;
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%u
  ", active) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
  
  static ssize_t wakeup_total_time_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	s64 msec = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		msec = ktime_to_ms(dev->power.wakeup->total_time);
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lld
  ", msec) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
  
  static ssize_t wakeup_max_time_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	s64 msec = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		msec = ktime_to_ms(dev->power.wakeup->max_time);
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lld
  ", msec) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
  
  static ssize_t wakeup_last_time_show(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	s64 msec = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		msec = ktime_to_ms(dev->power.wakeup->last_time);
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lld
  ", msec) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
  
  #ifdef CONFIG_PM_AUTOSLEEP
  static ssize_t wakeup_prevent_sleep_time_show(struct device *dev,
  					      struct device_attribute *attr,
  					      char *buf)
  {
  	s64 msec = 0;
  	bool enabled = false;
  
  	spin_lock_irq(&dev->power.lock);
  	if (dev->power.wakeup) {
  		msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
  		enabled = true;
  	}
  	spin_unlock_irq(&dev->power.lock);
  	return enabled ? sprintf(buf, "%lld
  ", msec) : sprintf(buf, "
  ");
  }
  
  static DEVICE_ATTR(wakeup_prevent_sleep_time_ms, 0444,
  		   wakeup_prevent_sleep_time_show, NULL);
  #endif /* CONFIG_PM_AUTOSLEEP */
  #endif /* CONFIG_PM_SLEEP */
  
  #ifdef CONFIG_PM_ADVANCED_DEBUG
  #ifdef CONFIG_PM_RUNTIME
  
  static ssize_t rtpm_usagecount_show(struct device *dev,
  				    struct device_attribute *attr, char *buf)
  {
  	return sprintf(buf, "%d
  ", atomic_read(&dev->power.usage_count));
  }
  
  static ssize_t rtpm_children_show(struct device *dev,
  				  struct device_attribute *attr, char *buf)
  {
  	return sprintf(buf, "%d
  ", dev->power.ignore_children ?
  		0 : atomic_read(&dev->power.child_count));
  }
  
  static ssize_t rtpm_enabled_show(struct device *dev,
  				 struct device_attribute *attr, char *buf)
  {
  	if ((dev->power.disable_depth) && (dev->power.runtime_auto == false))
  		return sprintf(buf, "disabled & forbidden
  ");
  	else if (dev->power.disable_depth)
  		return sprintf(buf, "disabled
  ");
  	else if (dev->power.runtime_auto == false)
  		return sprintf(buf, "forbidden
  ");
  	return sprintf(buf, "enabled
  ");
  }
  
  static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL);
  static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL);
  static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL);
  
  #endif
  
  #ifdef CONFIG_PM_SLEEP
  
  static ssize_t async_show(struct device *dev, struct device_attribute *attr,
  			  char *buf)
  {
  	return sprintf(buf, "%s
  ",
  			device_async_suspend_enabled(dev) ? enabled : disabled);
  }
  
  static ssize_t async_store(struct device *dev, struct device_attribute *attr,
  			   const char *buf, size_t n)
  {
  	char *cp;
  	int len = n;
  
  	cp = memchr(buf, '
  ', n);
  	if (cp)
  		len = cp - buf;
  	if (len == sizeof enabled - 1 && strncmp(buf, enabled, len) == 0)
  		device_enable_async_suspend(dev);
  	else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0)
  		device_disable_async_suspend(dev);
  	else
  		return -EINVAL;
  	return n;
  }
  
  static DEVICE_ATTR(async, 0644, async_show, async_store);
  
  #endif
  #endif /* CONFIG_PM_ADVANCED_DEBUG */
  
  static struct attribute *power_attrs[] = {
  #ifdef CONFIG_PM_ADVANCED_DEBUG
  #ifdef CONFIG_PM_SLEEP
  	&dev_attr_async.attr,
  #endif
  #ifdef CONFIG_PM_RUNTIME
  	&dev_attr_runtime_status.attr,
  	&dev_attr_runtime_usage.attr,
  	&dev_attr_runtime_active_kids.attr,
  	&dev_attr_runtime_enabled.attr,
  #endif
  #endif /* CONFIG_PM_ADVANCED_DEBUG */
  	NULL,
  };
  static struct attribute_group pm_attr_group = {
  	.name	= power_group_name,
  	.attrs	= power_attrs,
  };
  
  static struct attribute *wakeup_attrs[] = {
  #ifdef CONFIG_PM_SLEEP
  	&dev_attr_wakeup.attr,
  	&dev_attr_wakeup_count.attr,
  	&dev_attr_wakeup_active_count.attr,
  	&dev_attr_wakeup_abort_count.attr,
  	&dev_attr_wakeup_expire_count.attr,
  	&dev_attr_wakeup_active.attr,
  	&dev_attr_wakeup_total_time_ms.attr,
  	&dev_attr_wakeup_max_time_ms.attr,
  	&dev_attr_wakeup_last_time_ms.attr,
  #ifdef CONFIG_PM_AUTOSLEEP
  	&dev_attr_wakeup_prevent_sleep_time_ms.attr,
  #endif
  #endif
  	NULL,
  };
  static struct attribute_group pm_wakeup_attr_group = {
  	.name	= power_group_name,
  	.attrs	= wakeup_attrs,
  };
  
  static struct attribute *runtime_attrs[] = {
  #ifdef CONFIG_PM_RUNTIME
  #ifndef CONFIG_PM_ADVANCED_DEBUG
  	&dev_attr_runtime_status.attr,
  #endif
  	&dev_attr_control.attr,
  	&dev_attr_runtime_suspended_time.attr,
  	&dev_attr_runtime_active_time.attr,
  	&dev_attr_autosuspend_delay_ms.attr,
  #endif /* CONFIG_PM_RUNTIME */
  	NULL,
  };
  static struct attribute_group pm_runtime_attr_group = {
  	.name	= power_group_name,
  	.attrs	= runtime_attrs,
  };
  
  static struct attribute *pm_qos_latency_attrs[] = {
  #ifdef CONFIG_PM_RUNTIME
  	&dev_attr_pm_qos_resume_latency_us.attr,
  #endif /* CONFIG_PM_RUNTIME */
  	NULL,
  };
  static struct attribute_group pm_qos_latency_attr_group = {
  	.name	= power_group_name,
  	.attrs	= pm_qos_latency_attrs,
  };
  
  static struct attribute *pm_qos_flags_attrs[] = {
  #ifdef CONFIG_PM_RUNTIME
  	&dev_attr_pm_qos_no_power_off.attr,
  	&dev_attr_pm_qos_remote_wakeup.attr,
  #endif /* CONFIG_PM_RUNTIME */
  	NULL,
  };
  static struct attribute_group pm_qos_flags_attr_group = {
  	.name	= power_group_name,
  	.attrs	= pm_qos_flags_attrs,
  };
  
  int dpm_sysfs_add(struct device *dev)
  {
  	int rc;
  
  	rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
  	if (rc)
  		return rc;
  
  	if (pm_runtime_callbacks_present(dev)) {
  		rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
  		if (rc)
  			goto err_out;
  	}
  
  	if (device_can_wakeup(dev)) {
  		rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
  		if (rc) {
  			if (pm_runtime_callbacks_present(dev))
  				sysfs_unmerge_group(&dev->kobj,
  						    &pm_runtime_attr_group);
  			goto err_out;
  		}
  	}
  	return 0;
  
   err_out:
  	sysfs_remove_group(&dev->kobj, &pm_attr_group);
  	return rc;
  }
  
  int wakeup_sysfs_add(struct device *dev)
  {
  	return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
  }
  
  void wakeup_sysfs_remove(struct device *dev)
  {
  	sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
  }
  
  int pm_qos_sysfs_add_latency(struct device *dev)
  {
  	return sysfs_merge_group(&dev->kobj, &pm_qos_latency_attr_group);
  }
  
  void pm_qos_sysfs_remove_latency(struct device *dev)
  {
  	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_attr_group);
  }
  
  int pm_qos_sysfs_add_flags(struct device *dev)
  {
  	return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
  }
  
  void pm_qos_sysfs_remove_flags(struct device *dev)
  {
  	sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
  }
  
  void rpm_sysfs_remove(struct device *dev)
  {
  	sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
  }
  
  void dpm_sysfs_remove(struct device *dev)
  {
  	dev_pm_qos_constraints_destroy(dev);
  	rpm_sysfs_remove(dev);
  	sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
  	sysfs_remove_group(&dev->kobj, &pm_attr_group);
  }