power_supply: add SCOPE attribute to power supplies
This adds a "scope" attribute to a power_supply, which indicates how
much of the system it powers. It appears in sysfs as "scope" or in
the uevent file as POWER_SUPPLY_SCOPE=. There are presently three
possible values:
Unknown - unknown power topology
System - the power supply powers the whole system
Device - it powers a specific device, or tree of devices
A power supply which doesn't have a "scope" attribute should be assumed to
have "System" scope.
In general, usermode should assume that loss of all System-scoped power
supplies will power off the whole system, but any single one is sufficient
to power the system.
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Richard Hughes <richard@hughsie.com>
2 files changed