1*4882a593SmuzhiyunWhat: /sys/devices/.../real_power_state 2*4882a593SmuzhiyunDate: January 2013 3*4882a593SmuzhiyunContact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 4*4882a593SmuzhiyunDescription: 5*4882a593Smuzhiyun The /sys/devices/.../real_power_state attribute is only present 6*4882a593Smuzhiyun for device objects representing ACPI device nodes that provide 7*4882a593Smuzhiyun power management methods and use ACPI power resources for power 8*4882a593Smuzhiyun management. 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun If present, it contains a string representing the real ACPI 11*4882a593Smuzhiyun power state of the given device node as returned by the _PSC 12*4882a593Smuzhiyun control method or inferred from the configuration of power 13*4882a593Smuzhiyun resources. Its possible values, "D0", "D1", "D2", "D3hot", and 14*4882a593Smuzhiyun "D3cold", reflect the power state names defined by the ACPI 15*4882a593Smuzhiyun specification (ACPI 4 and above). 16*4882a593Smuzhiyun 17*4882a593Smuzhiyun In some situations the value of this attribute may be different 18*4882a593Smuzhiyun from the value of the /sys/devices/.../power_state attribute for 19*4882a593Smuzhiyun the same device object. If that happens, some shared power 20*4882a593Smuzhiyun resources used by the device node are only ON because of some 21*4882a593Smuzhiyun other devices using them at the moment. 22*4882a593Smuzhiyun 23*4882a593Smuzhiyun This attribute is read-only. 24