diff options
Diffstat (limited to 'Documentation/ABI/testing/sysfs-devices-power_state')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-power_state | 20 |
1 files changed, 20 insertions, 0 deletions
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. |