Add an operation to read EDID, since bridge may have ability to read
EDID from the panel that is connected to it, for example LCD<->eDP bridge.
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
A video bridge typically converts video from one format to another, e.g.
DisplayPort to LVDS. Add driver model support for these with a simple
interface to control activation and backlight. The uclass supports GPIO
control of power and reset lines.
Signed-off-by: Simon Glass <sjg@chromium.org>