1 What: /sys/devices/.../power_state 1 What: /sys/devices/.../power_state
2 Date: January 2013 2 Date: January 2013
3 Contact: Rafael J. Wysocki <rafael.j.wys 3 Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
4 Description: 4 Description:
5 The /sys/devices/.../power_sta 5 The /sys/devices/.../power_state attribute is only present for
6 device objects representing AC 6 device objects representing ACPI device nodes that provide power
7 management methods. 7 management methods.
8 8
9 If present, it contains a stri 9 If present, it contains a string representing the current ACPI
10 power state of the given devic 10 power state of the given device node. Its possible values,
11 "D0", "D1", "D2", "D3hot", and 11 "D0", "D1", "D2", "D3hot", and "D3cold", reflect the power state
12 names defined by the ACPI spec 12 names defined by the ACPI specification (ACPI 4 and above).
13 13
14 If the device node uses shared 14 If the device node uses shared ACPI power resources, this state
15 determines a list of power res 15 determines a list of power resources required not to be turned
16 off. However, some power reso 16 off. However, some power resources needed by the device node in
17 higher-power (lower-number) st 17 higher-power (lower-number) states may also be ON because of
18 some other devices using them 18 some other devices using them at the moment.
19 19
20 This attribute is read-only. 20 This attribute is read-only.
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