Re: [PATCH] i915: Quirk out disconnected backlight

From: Matthew Garrett
Date: Fri Sep 14 2012 - 10:40:46 EST


On Fri, Sep 14, 2012 at 03:29:14PM +0100, David Woodhouse wrote:
> On Fri, 2012-09-14 at 14:48 +0100, Matthew Garrett wrote:
> > On Fri, Sep 14, 2012 at 01:57:06PM +0100, Grant Likely wrote:
> >
> > > Tested on MacbookPro8,3. Without this patch both the intel_backlight and
> > > gmux_backlight devices get registered and userspace doesn't know which
> > > it should use.
> >
> > Userspace should be figuring out which one to use from the type field.
>
> It only does that if it's using gsd-backlight-helper to poke
> at /sys/class/backlight directly. If X exposes a backlight, (as it does
> for the Intel backlight), then gsd will just use that.

Yeah, X should be doing the same. If it's not then it's broken. OTOH, I
do agree that if we already know that we can't do anything with the
backlight (as is clearly the case if the PWM field is 0) we should just
disable it.

--
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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