[PATCH] drm/radeon/kms: fix tv dac conflict resolver

[GhePeU]

Il giorno mar, 27/04/2010 alle 18.11 -0400, Alex Deucher ha scritto:
> On Tue, Apr 27, 2010 at 5:30 PM, GhePeU <ghepeu at virgilio.it> wrote:
> > Il giorno gio, 15/04/2010 alle 13.41 -0400, Alex Deucher ha scritto:
> >> >From 837feb147c531219c7315857a6f17e145af8f750 Mon Sep 17 00:00:00 2001
> >> From: Alex Deucher <alexdeucher at gmail.com>
> >> Date: Thu, 15 Apr 2010 13:31:12 -0400
> >> Subject: [PATCH] drm/radeon/kms: fix tv dac conflict resolver
> >
> > Hi,
> >
> > a few days ago I upgraded to the last 2.6.34 rc kernel and found that with
> > KMS both the console and X were using a 800x600 resolution instead of my LCD
> > display's native resolution of 1440x900 who was selected by default with
> > 2.6.33 and previous kernels.
> >
> > I tracked the problem to this patch, which causes the same issues also
> > when manually applied to 2.6.33: apparently the kms radeon driver
> > wrongly detects a TV connected to my card (I don't have one, only a LCD
> > display connected to the DVI port) and forces the TV default resolution
> > for all the outputs.
> 
> You issue is not related to the patch.  What the patch does is allow
> you to use the digital part of DVI plus TV at the same time.  The
> analog part of the DVI port and the TV share the same DAC so they
> can't be used at the same time.  Prior to the patch, both the TV and
> DVI were detected as attached, but the TV was always disabled since it
> was wrongly seen as conflicting with the DVI.
> 
> Your issue is actually a matter of load detection for TV not always
> being reliable.  I don't know what a proper fix would be.  We could
> disable load detection for TV to avoid false positives, but that would
> prevent automatic detection of TV which does work in most cases.
> 
> Alex
> 

With UMS however I don't have this problem, is the logic different? 

Shouldn't the driver behavior with KMS be the same, in this case? At
least there wouldn't be (apparent) regressions like the one I'm
experiencing.

Giacomo