[PATCH v2 1/3] backlight: introduce backlight_device_registered

[Igor Gnatenko]

On Tue, 2013-09-17 at 17:23 +0800, Aaron Lu wrote:
> Introduce a new API for modules to query if a specific type of backlight
> device has been registered. This is useful for some backlight device
> provider module(e.g. ACPI video) to know if a native control
> interface(e.g. the interface created by i915) is available and then do
> things accordingly(e.g. avoid register its own on Win8 systems).
> 
> Signed-off-by: Aaron Lu <aaron.lu at intel.com>
Tested-by: Igor Gnatenko <i.gnatenko.brain at gmail.com>
> ---
>  drivers/video/backlight/backlight.c | 31 +++++++++++++++++++++++++++++++
>  include/linux/backlight.h           |  4 ++++
>  2 files changed, 35 insertions(+)

-- 
Igor Gnatenko
Fedora release 20 (Heisenbug)
Linux 3.12.0-0.rc1.git0.1.fc20.x86_64