[Intel-gfx] [PATCH v3 2/2] drivers: i915: Default max backlight brightness value

[Matthew Garrett]

On Tue, Nov 08, 2011 at 03:02:00PM -0800, Olof Johansson wrote:

> How about a DMI table check that overrides whatever is setup (or not
> setup) from the video bios? We know exactly what platforms need this
> so that table would be easy to specify.

dmi's horribly unscalable. It's much better to have a communication 
channel that doesn't require new code for new models of the same 
platform.

> I'm not sure how well this would fit into our platform layer code, it
> would be pretty nasty to have to export the default backlight variable
> from the i915 driver and modify it from there as well, and I'm sure
> noone wants to see any kind of chromeos-specific code paths in the 915
> driver (myself included).

Well right now this path is (effectively) chromeos-specific. Refactoring 
the code so we just have the register readback as a single information 
source and allow the existing platform-specific code to hook in would be 
conceptually cleaner. But then maybe this is grotesque over-engineering 
and we should just hack this case.

-- 
Matthew Garrett | mjg59 at srcf.ucam.org