[Nouveau] [PATCH v3 5/7] drm/nouveau: utilize subconnector property for DP

[Ilia Mirkin]

On Wed, Aug 28, 2019 at 10:54 AM Ville Syrjälä
<ville.syrjala at linux.intel.com> wrote:
>
> On Wed, Aug 28, 2019 at 10:47:08AM -0400, Ilia Mirkin wrote:
> > On Wed, Aug 28, 2019 at 10:38 AM Ville Syrjälä
> > <ville.syrjala at linux.intel.com> wrote:
> > >
> > > On Mon, Aug 26, 2019 at 09:36:50AM -0400, Ilia Mirkin wrote:
> > > > This should probably be fixed to account for the scenario where an
> > > > HDMI connector is plugged directly into the DP++ port. I don't think
> > > > the dp.subconnector property will be valid in that case.
> > > > (Unfortunately I don't remember how one detects that particular
> > > > situation.)
> > >
> > > One may or may not be able to detect it very well. I've seen dongles
> > > that automagically change the DFP type from DP++ to DP/HDMI depending
> > > on what's plugged in, and I've also seen dongles that leave the DFP
> > > type to DP++.
> >
> > Well, our internal logic certainly knows if it's driving DP or TMDS. I
> > just don't remember how it knows this.
>
> You'll be driving DP in this case. The DFP will be the one driving
> DP or TMDS depending on what's plugged in.

OK. That's not the case I was worried about though :)

I'm worried about the case where you plug a true HDMI thing into the
DP port, which will then be driven by HDMI and none of the dp.* things
will be set (I don't remember, but they might even be in a union). I
think Intel multiplies connectors for this, but nouveau/amd just have
a single connector that handles both.

  -ilia