Documentation/ABI/testing/sysfs-devices-real_power_state

   1 What:           /sys/devices/.../real_power_state
   2 Date:           January 2013
   3 Contact:        Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   4 Description:
   5                 The /sys/devices/.../real_power_state attribute is only present
   6                 for device objects representing ACPI device nodes that provide
   7                 power management methods and use ACPI power resources for power
   8                 management.
   9
  10                 If present, it contains a string representing the real ACPI
  11                 power state of the given device node as returned by the _PSC
  12                 control method or inferred from the configuration of power
  13                 resources.  Its possible values, "D0", "D1", "D2", "D3hot", and
  14                 "D3cold", reflect the power state names defined by the ACPI
  15                 specification (ACPI 4 and above).
  16
  17                 In some situations the value of this attribute may be different
  18                 from the value of the /sys/devices/.../power_state attribute for
  19                 the same device object.  If that happens, some shared power
  20                 resources used by the device node are only ON because of some
  21                 other devices using them at the moment.
  22
  23                 This attribute is read-only.