[Intel-gfx] v3.14-rc7: Backlight control broken on Dell XPS13

[Jani Nikula]

On Mon, 17 Mar 2014, Romain Francoise <romain at orebokech.com> wrote:
> Hi Daniel,
>
> Daniel Vetter <daniel.vetter at ffwll.ch> writes:
>
>> Please never just send a mail to maintainers, always cc mailing lists.
>
> Yes, sorry, I sent this privately because it wasn't a fully-formed bug
> report; I just wanted Jani to confirm that it wasn't intentionally
> broken as of -rc7.
>
>> Have you tested with the patch reverted to confirm that it's indeed
>> this commit and not something else (e.g. in the acpi code)?
>
> I hadn't, but I've now reverted the revert and things work again as in
> v3.13. So as far as I can tell the quirk is still definitely needed.

I still don't think having the quirk is the way to go. Let's fix this
properly, shall we?

Please file a new bug on DRM/Intel component at [1]. Please attach
intel_reg_dumper output (tool from intel-gpu-tools [2]) with and without
the revert. Please also attach dmesg with drm.debug=0xe from early boot.

Do you have the snb or ivb model?

BR,
Jani.


[1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI
[2] http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/

>
> Thanks!
> -r

-- 
Jani Nikula, Intel Open Source Technology Center