1*836aedb1SRafael J. WysockiWhat: /sys/devices/.../power_state 2*836aedb1SRafael J. WysockiDate: January 2013 3*836aedb1SRafael J. WysockiContact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 4*836aedb1SRafael J. WysockiDescription: 5*836aedb1SRafael J. Wysocki The /sys/devices/.../power_state attribute is only present for 6*836aedb1SRafael J. Wysocki device objects representing ACPI device nodes that provide power 7*836aedb1SRafael J. Wysocki management methods. 8*836aedb1SRafael J. Wysocki 9*836aedb1SRafael J. Wysocki If present, it contains a string representing the current ACPI 10*836aedb1SRafael J. Wysocki power state of the given device node. Its possible values, 11*836aedb1SRafael J. Wysocki "D0", "D1", "D2", "D3hot", and "D3cold", reflect the power state 12*836aedb1SRafael J. Wysocki names defined by the ACPI specification (ACPI 4 and above). 13*836aedb1SRafael J. Wysocki 14*836aedb1SRafael J. Wysocki If the device node uses shared ACPI power resources, this state 15*836aedb1SRafael J. Wysocki determines a list of power resources required not to be turned 16*836aedb1SRafael J. Wysocki off. However, some power resources needed by the device node in 17*836aedb1SRafael J. Wysocki higher-power (lower-number) states may also be ON because of 18*836aedb1SRafael J. Wysocki some other devices using them at the moment. 19*836aedb1SRafael J. Wysocki 20*836aedb1SRafael J. Wysocki This attribute is read-only. 21