[PATCH] drm/radeon: add new AMD ACPI header and update relevant code

[Alex Deucher]

On Sun, Jul 29, 2012 at 3:33 PM, Luca Tettamanti <kronos.it at gmail.com> wrote:
> Hi,
> I'm attaching a first draft of my work. The first 3 patches are
> infrastructure work, the fourth wires the notification handler and
> retrieves the requests from the system BIOS, but it does not actually
> change brightness yet.
>
> The problem here is how to get the correct encoder: should I just scan
> encoder_list checking for ATOM_DEVICE_LCD_SUPPORT and see if it has a
> backlight device attached?

Yeah, that should work.

> Hopefully there is only one encoder with it, right?

There's only one backlight controller and there should only be one
encoder with it enabled on it.

>
> I'm also toying with the idea of creating structures matching the output
> of the various ACPI methods, this would remove some ugly pointer
> arithmetics, but it _might_ make it easier to read past the buffer if
> one does not check the size before using the struct. What do you think?

That's fine with me.  We do something similar with atombios structs.
Also, feel free to add stuff to radeon_acpi.h if you think it's
useful.

Alex