linux/Documentation/ABI/testing/sysfs-devices-power_resources_D2

What:		/sys/devices/.../power_resources_D2/
Date:		January 2013
Contact:	Rafael J. Wysocki <[email protected]>
Description:
		The /sys/devices/.../power_resources_D2/ directory is only
		present for device objects representing ACPI device nodes that
		use ACPI power resources for power management and support ACPI
		power state D2.

		If present, it contains symbolic links to device directories
		representing ACPI power resources that need to be turned on for
		the given device node to be in ACPI power state D2.  The names
		of the links are the same as the names of the directories they
		point to.