Add framework to generate ACPI methods in SSDT for
screen backlight control. Adjust params for gtt_ methods
to match prototypes in i915.h and avoid conflicts.
To make use of this, individual boards will need to
include default_brightness_levels.asl in their dsdt, as
well as add 'register "gfx" = "GMA_STATIC_DISPLAYS(0)"' to
their devicetree.
Change-Id: If93b7690ef36b5d19ca43957e8a1bef91ec5821d
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39941
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
53e24468f0