| 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. |