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Diffstat (limited to 'Documentation/ABI/testing/sysfs-devices-real_power_state')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-real_power_state | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-real_power_state b/Documentation/ABI/testing/sysfs-devices-real_power_state new file mode 100644 index 000000000000..8b3527c82a7d --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-real_power_state @@ -0,0 +1,23 @@ +What: /sys/devices/.../real_power_state +Date: January 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../real_power_state attribute is only present + for device objects representing ACPI device nodes that provide + power management methods and use ACPI power resources for power + management. + + If present, it contains a string representing the real ACPI + power state of the given device node as returned by the _PSC + control method or inferred from the configuration of power + resources. Its possible values, "D0", "D1", "D2", "D3hot", and + "D3cold", reflect the power state names defined by the ACPI + specification (ACPI 4 and above). + + In some situations the value of this attribute may be different + from the value of the /sys/devices/.../power_state attribute for + the same device object. If that happens, some shared power + resources used by the device node are only ON because of some + other devices using them at the moment. + + This attribute is read-only. |