1836aedb1SRafael J. WysockiWhat: /sys/devices/.../power_state 2836aedb1SRafael J. WysockiDate: January 2013 3836aedb1SRafael J. WysockiContact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 4836aedb1SRafael J. WysockiDescription: 5836aedb1SRafael J. Wysocki The /sys/devices/.../power_state attribute is only present for 6836aedb1SRafael J. Wysocki device objects representing ACPI device nodes that provide power 7836aedb1SRafael J. Wysocki management methods. 8836aedb1SRafael J. Wysocki 9836aedb1SRafael J. Wysocki If present, it contains a string representing the current ACPI 10836aedb1SRafael J. Wysocki power state of the given device node. Its possible values, 11836aedb1SRafael J. Wysocki "D0", "D1", "D2", "D3hot", and "D3cold", reflect the power state 12836aedb1SRafael J. Wysocki names defined by the ACPI specification (ACPI 4 and above). 13836aedb1SRafael J. Wysocki 14836aedb1SRafael J. Wysocki If the device node uses shared ACPI power resources, this state 15836aedb1SRafael J. Wysocki determines a list of power resources required not to be turned 16836aedb1SRafael J. Wysocki off. However, some power resources needed by the device node in 17836aedb1SRafael J. Wysocki higher-power (lower-number) states may also be ON because of 18836aedb1SRafael J. Wysocki some other devices using them at the moment. 19836aedb1SRafael J. Wysocki 20836aedb1SRafael J. Wysocki This attribute is read-only. 21