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-rw-r--r--Documentation/ABI/testing/sysfs-devices-power271
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_resources_D013
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_resources_D114
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_resources_D214
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_resources_D3hot14
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_resources_wakeup13
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power_state20
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diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power
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+What: /sys/devices/.../power/
+Date: January 2009
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power directory contains attributes
+ allowing the user space to check and modify some power
+ management related properties of given device.
+
+What: /sys/devices/.../power/wakeup
+Date: January 2009
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/wakeup attribute allows the user
+ space to check if the device is enabled to wake up the system
+ from sleep states, such as the memory sleep state (suspend to
+ RAM) and hibernation (suspend to disk), and to enable or disable
+ it to do that as desired.
+
+ Some devices support "wakeup" events, which are hardware signals
+ used to activate the system from a sleep state. Such devices
+ have one of the following two values for the sysfs power/wakeup
+ file:
+
+ + "enabled\n" to issue the events;
+ + "disabled\n" not to do so;
+
+ In that cases the user space can change the setting represented
+ by the contents of this file by writing either "enabled", or
+ "disabled" to it.
+
+ For the devices that are not capable of generating system wakeup
+ events this file is not present. In that case the device cannot
+ be enabled to wake up the system from sleep states.
+
+What: /sys/devices/.../power/control
+Date: January 2009
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/control attribute allows the user
+ space to control the run-time power management of the device.
+
+ All devices have one of the following two values for the
+ power/control file:
+
+ + "auto\n" to allow the device to be power managed at run time;
+ + "on\n" to prevent the device from being power managed;
+
+ The default for all devices is "auto", which means that they 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.
+
+What: /sys/devices/.../power/async
+Date: January 2009
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../async attribute allows the user space to
+ enable or diasble the device's suspend and resume callbacks to
+ be executed asynchronously (ie. in separate threads, in parallel
+ with the main suspend/resume thread) during system-wide power
+ transitions (eg. suspend to RAM, hibernation).
+
+ All devices have one of the following two values for the
+ power/async file:
+
+ + "enabled\n" to permit the asynchronous suspend/resume;
+ + "disabled\n" to forbid it;
+
+ The value of this attribute may be changed by writing either
+ "enabled", or "disabled" to it.
+
+ 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.
+
+What: /sys/devices/.../power/wakeup_count
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_count attribute contains the number
+ of signaled wakeup events associated with the device. This
+ attribute is read-only. If the device is not capable to wake up
+ the system from sleep states, this attribute is not present.
+ If the device is not enabled to wake up the system from sleep
+ states, this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_active_count
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_active_count attribute contains the
+ number of times the processing of wakeup events associated with
+ the device was completed (at the kernel level). This attribute
+ is read-only. If the device is not capable to wake up the
+ system from sleep states, this attribute is not present. If
+ the device is not enabled to wake up the system from sleep
+ states, this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_abort_count
+Date: February 2012
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_abort_count attribute contains the
+ number of times the processing of a wakeup event associated with
+ the device might have aborted system transition into a sleep
+ state in progress. This attribute is read-only. If the device
+ is not capable to wake up the system from sleep states, this
+ attribute is not present. If the device is not enabled to wake
+ up the system from sleep states, this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_expire_count
+Date: February 2012
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_expire_count attribute contains the
+ number of times a wakeup event associated with the device has
+ been reported with a timeout that expired. This attribute is
+ read-only. If the device is not capable to wake up the system
+ from sleep states, this attribute is not present. If the
+ device is not enabled to wake up the system from sleep states,
+ this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_active
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_active attribute contains either 1,
+ or 0, depending on whether or not a wakeup event associated with
+ the device is being processed (1). This attribute is read-only.
+ If the device is not capable to wake up the system from sleep
+ states, this attribute is not present. If the device is not
+ enabled to wake up the system from sleep states, this attribute
+ is empty.
+
+What: /sys/devices/.../power/wakeup_total_time_ms
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_total_time_ms attribute contains
+ the total time of processing wakeup events associated with the
+ device, in milliseconds. This attribute is read-only. If the
+ device is not capable to wake up the system from sleep states,
+ this attribute is not present. If the device is not enabled to
+ wake up the system from sleep states, this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_max_time_ms
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_max_time_ms attribute contains
+ the maximum time of processing a single wakeup event associated
+ with the device, in milliseconds. This attribute is read-only.
+ If the device is not capable to wake up the system from sleep
+ states, this attribute is not present. If the device is not
+ enabled to wake up the system from sleep states, this attribute
+ is empty.
+
+What: /sys/devices/.../power/wakeup_last_time_ms
+Date: September 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_last_time_ms attribute contains
+ the value of the monotonic clock corresponding to the time of
+ signaling the last wakeup event associated with the device, in
+ milliseconds. This attribute is read-only. If the device is
+ not enabled to wake up the system from sleep states, this
+ attribute is not present. If the device is not enabled to wake
+ up the system from sleep states, this attribute is empty.
+
+What: /sys/devices/.../power/wakeup_prevent_sleep_time_ms
+Date: February 2012
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../wakeup_prevent_sleep_time_ms attribute
+ contains the total time the device has been preventing
+ opportunistic transitions to sleep states from occurring.
+ This attribute is read-only. If the device is not capable to
+ wake up the system from sleep states, this attribute is not
+ present. If the device is not enabled to wake up the system
+ from sleep states, this attribute is empty.
+
+What: /sys/devices/.../power/autosuspend_delay_ms
+Date: September 2010
+Contact: Alan Stern <stern@rowland.harvard.edu>
+Description:
+ The /sys/devices/.../power/autosuspend_delay_ms attribute
+ contains the autosuspend delay value (in milliseconds). Some
+ drivers do not want their device to suspend as soon as it
+ becomes idle at run time; they want the device to remain
+ inactive for a certain minimum period of time first. That
+ period is called the autosuspend delay. Negative values will
+ prevent the device from being suspended at run time (similar
+ to writing "on" to the power/control attribute). Values >=
+ 1000 will cause the autosuspend timer expiration to be rounded
+ up to the nearest second.
+
+ Not all drivers support this attribute. If it isn't supported,
+ attempts to read or write it will yield I/O errors.
+
+What: /sys/devices/.../power/pm_qos_resume_latency_us
+Date: March 2012
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/pm_qos_resume_latency_us attribute
+ contains the PM QoS resume latency limit for the given device,
+ which is the maximum allowed time it can take to resume the
+ device, after it has been suspended at run time, from a resume
+ request to the moment the device will be ready to process I/O,
+ in microseconds. If it is equal to 0, however, this means that
+ the PM QoS resume latency may be arbitrary and the special value
+ "n/a" means that user space cannot accept any resume latency at
+ all for the given device.
+
+ Not all drivers support this attribute. If it isn't supported,
+ it is not present.
+
+ This attribute has no effect on system-wide suspend/resume and
+ hibernation.
+
+What: /sys/devices/.../power/pm_qos_latency_tolerance_us
+Date: January 2014
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/pm_qos_latency_tolerance_us attribute
+ contains the PM QoS active state latency tolerance limit for the
+ given device in microseconds. That is the maximum memory access
+ latency the device can suffer without any visible adverse
+ effects on user space functionality. If that value is the
+ string "any", the latency does not matter to user space at all,
+ but hardware should not be allowed to set the latency tolerance
+ for the device automatically.
+
+ Reading "auto" from this file means that the maximum memory
+ access latency for the device may be determined automatically
+ by the hardware as needed. Writing "auto" to it allows the
+ hardware to be switched to this mode if there are no other
+ latency tolerance requirements from the kernel side.
+
+ This attribute is only present if the feature controlled by it
+ is supported by the hardware.
+
+ This attribute has no effect on runtime suspend and resume of
+ devices and on system-wide suspend/resume and hibernation.
+
+What: /sys/devices/.../power/pm_qos_no_power_off
+Date: September 2012
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/pm_qos_no_power_off attribute
+ is used for manipulating the PM QoS "no power off" flag. If
+ set, this flag indicates to the kernel that power should not
+ be removed entirely from the device.
+
+ Not all drivers support this attribute. If it isn't supported,
+ it is not present.
+
+ This attribute has no effect on system-wide suspend/resume and
+ hibernation.
+
+What: /sys/devices/.../power/runtime_status
+Date: April 2010
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
+Description:
+ The /sys/devices/.../power/runtime_status attribute contains
+ the current runtime PM status of the device, which may be
+ "suspended", "suspending", "resuming", "active", "error" (fatal
+ error), or "unsupported" (runtime PM is disabled).
diff --git a/Documentation/ABI/testing/sysfs-devices-power_resources_D0 b/Documentation/ABI/testing/sysfs-devices-power_resources_D0
new file mode 100644
index 000000000..73b77a6be
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_resources_D0
@@ -0,0 +1,13 @@
+What: /sys/devices/.../power_resources_D0/
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_resources_D0/ directory is only
+ present for device objects representing ACPI device nodes that
+ use ACPI power resources for power management.
+
+ If present, it contains symbolic links to device directories
+ representing ACPI power resources that need to be turned on for
+ the given device node to be in ACPI power state D0. The names
+ of the links are the same as the names of the directories they
+ point to.
diff --git a/Documentation/ABI/testing/sysfs-devices-power_resources_D1 b/Documentation/ABI/testing/sysfs-devices-power_resources_D1
new file mode 100644
index 000000000..30c20703f
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_resources_D1
@@ -0,0 +1,14 @@
+What: /sys/devices/.../power_resources_D1/
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_resources_D1/ directory is only
+ present for device objects representing ACPI device nodes that
+ use ACPI power resources for power management and support ACPI
+ power state D1.
+
+ If present, it contains symbolic links to device directories
+ representing ACPI power resources that need to be turned on for
+ the given device node to be in ACPI power state D1. The names
+ of the links are the same as the names of the directories they
+ point to.
diff --git a/Documentation/ABI/testing/sysfs-devices-power_resources_D2 b/Documentation/ABI/testing/sysfs-devices-power_resources_D2
new file mode 100644
index 000000000..fd9d84b42
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_resources_D2
@@ -0,0 +1,14 @@
+What: /sys/devices/.../power_resources_D2/
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_resources_D2/ directory is only
+ present for device objects representing ACPI device nodes that
+ use ACPI power resources for power management and support ACPI
+ power state D2.
+
+ If present, it contains symbolic links to device directories
+ representing ACPI power resources that need to be turned on for
+ the given device node to be in ACPI power state D2. The names
+ of the links are the same as the names of the directories they
+ point to.
diff --git a/Documentation/ABI/testing/sysfs-devices-power_resources_D3hot b/Documentation/ABI/testing/sysfs-devices-power_resources_D3hot
new file mode 100644
index 000000000..3df32c20a
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_resources_D3hot
@@ -0,0 +1,14 @@
+What: /sys/devices/.../power_resources_D3hot/
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_resources_D3hot/ directory is only
+ present for device objects representing ACPI device nodes that
+ use ACPI power resources for power management and support ACPI
+ power state D3hot.
+
+ If present, it contains symbolic links to device directories
+ representing ACPI power resources that need to be turned on for
+ the given device node to be in ACPI power state D3hot. The
+ names of the links are the same as the names of the directories
+ they point to.
diff --git a/Documentation/ABI/testing/sysfs-devices-power_resources_wakeup b/Documentation/ABI/testing/sysfs-devices-power_resources_wakeup
new file mode 100644
index 000000000..e0588feeb
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_resources_wakeup
@@ -0,0 +1,13 @@
+What: /sys/devices/.../power_resources_wakeup/
+Date: April 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_resources_wakeup/ directory is only
+ present for device objects representing ACPI device nodes that
+ require ACPI power resources for wakeup signaling.
+
+ If present, it contains symbolic links to device directories
+ representing ACPI power resources that need to be turned on for
+ the given device node to be able to signal wakeup. The names of
+ the links are the same as the names of the directories they
+ point to.
diff --git a/Documentation/ABI/testing/sysfs-devices-power_state b/Documentation/ABI/testing/sysfs-devices-power_state
new file mode 100644
index 000000000..7ad954674
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-devices-power_state
@@ -0,0 +1,20 @@
+What: /sys/devices/.../power_state
+Date: January 2013
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ The /sys/devices/.../power_state attribute is only present for
+ device objects representing ACPI device nodes that provide power
+ management methods.
+
+ If present, it contains a string representing the current ACPI
+ power state of the given device node. Its possible values,
+ "D0", "D1", "D2", "D3hot", and "D3cold", reflect the power state
+ names defined by the ACPI specification (ACPI 4 and above).
+
+ If the device node uses shared ACPI power resources, this state
+ determines a list of power resources required not to be turned
+ off. However, some power resources needed by the device node in
+ higher-power (lower-number) states may also be ON because of
+ some other devices using them at the moment.
+
+ This attribute is read-only.