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-rw-r--r--Documentation/ABI/testing/sysfs-power63
1 files changed, 44 insertions, 19 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 31725ffeeb3..f4551816329 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -1,28 +1,40 @@
What: /sys/power/
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power directory will contain files that will
provide a unified interface to the power management
subsystem.
What: /sys/power/state
-Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Date: May 2014
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
- The /sys/power/state file controls the system power state.
- Reading from this file returns what states are supported,
- which is hard-coded to 'standby' (Power-On Suspend), 'mem'
- (Suspend-to-RAM), and 'disk' (Suspend-to-Disk).
+ The /sys/power/state file controls system sleep states.
+ Reading from this file returns the available sleep state
+ labels, which may be "mem", "standby", "freeze" and "disk"
+ (hibernation). The meanings of the first three labels depend on
+ the relative_sleep_states command line argument as follows:
+ 1) relative_sleep_states = 1
+ "mem", "standby", "freeze" represent non-hibernation sleep
+ states from the deepest ("mem", always present) to the
+ shallowest ("freeze"). "standby" and "freeze" may or may
+ not be present depending on the capabilities of the
+ platform. "freeze" can only be present if "standby" is
+ present.
+ 2) relative_sleep_states = 0 (default)
+ "mem" - "suspend-to-RAM", present if supported.
+ "standby" - "power-on suspend", present if supported.
+ "freeze" - "suspend-to-idle", always present.
Writing to this file one of these strings causes the system to
- transition into that state. Please see the file
- Documentation/power/states.txt for a description of each of
- these states.
+ transition into the corresponding state, if available. See
+ Documentation/power/states.txt for a description of what
+ "suspend-to-RAM", "power-on suspend" and "suspend-to-idle" mean.
What: /sys/power/disk
Date: September 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/disk file controls the operating mode of the
suspend-to-disk mechanism. Reading from this file returns
@@ -67,7 +79,7 @@ Description:
What: /sys/power/image_size
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/image_size file controls the size of the image
created by the suspend-to-disk mechanism. It can be written a
@@ -84,7 +96,7 @@ Description:
What: /sys/power/pm_trace
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/pm_trace file controls the code which saves the
last PM event point in the RTC across reboots, so that you can
@@ -133,7 +145,7 @@ Description:
What: /sys/power/pm_async
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/pm_async file controls the switch allowing the
user space to enable or disable asynchronous suspend and resume
@@ -146,7 +158,7 @@ Description:
What: /sys/power/wakeup_count
Date: July 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wakeup_count file allows user space to put the
system into a sleep state while taking into account the
@@ -161,7 +173,7 @@ Description:
What: /sys/power/reserved_size
Date: May 2011
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/reserved_size file allows user space to control
the amount of memory reserved for allocations made by device
@@ -175,7 +187,7 @@ Description:
What: /sys/power/autosleep
Date: April 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/autosleep file can be written one of the strings
returned by reads from /sys/power/state. If that happens, a
@@ -192,7 +204,7 @@ Description:
What: /sys/power/wake_lock
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wake_lock file allows user space to create
wakeup source objects and activate them on demand (if one of
@@ -219,7 +231,7 @@ Description:
What: /sys/power/wake_unlock
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wake_unlock file allows user space to deactivate
wakeup sources created with the help of /sys/power/wake_lock.
@@ -231,3 +243,16 @@ Description:
Reads from this file return a string consisting of the names of
wakeup sources created with the help of /sys/power/wake_lock
that are inactive at the moment, separated with spaces.
+
+What: /sys/power/pm_print_times
+Date: May 2012
+Contact: Sameer Nanda <snanda@chromium.org>
+Description:
+ The /sys/power/pm_print_times file allows user space to
+ control whether the time taken by devices to suspend and
+ resume is printed. These prints are useful for hunting down
+ devices that take too long to suspend or resume.
+
+ Writing a "1" enables this printing while writing a "0"
+ disables it. The default value is "0". Reading from this file
+ will display the current value.