renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-26 14:14:01 +08:00
Code
f9bc754be4
linux-next/Documentation/ABI/testing/sysfs-devices-power_resources_D2

15 lines
614 B
Plaintext
Raw Normal View History

ACPI / PM: Expose lists of device power resources to user space Since ACPI power resources are going to be used more extensively on new hardware platforms, it is necessary to allow user space (powertop in particular) to look at the lists of power resources corresponding to different power states of devices for diagnostics and control purposes. For this reason, for each power state of an ACPI device node using power resources create a special attribute group under the device node's directory in sysfs containing links to sysfs directories representing the power resources in that list. The names of the new attribute groups are "power_resources_<state>", where <state> is the state name i.e. "D0", "D1", "D2", or "D3hot". Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-26 04:51:32 +08:00
What: /sys/devices/.../power_resources_D2/
Date: January 2013
Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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.
Copy Permalink