[PATCH v4 3/7] drm: Add DisplayPort colorspace property

[Ilia Mirkin]

On Fri, Sep 6, 2019 at 7:43 AM Ville Syrjälä
<ville.syrjala at linux.intel.com> wrote:
>
> On Fri, Sep 06, 2019 at 11:31:55AM +0000, Shankar, Uma wrote:
> >
> >
> > >-----Original Message-----
> > >From: Ilia Mirkin <imirkin at alum.mit.edu>
> > >Sent: Tuesday, September 3, 2019 6:12 PM
> > >To: Mun, Gwan-gyeong <gwan-gyeong.mun at intel.com>
> > >Cc: Intel Graphics Development <intel-gfx at lists.freedesktop.org>; Shankar, Uma
> > ><uma.shankar at intel.com>; dri-devel <dri-devel at lists.freedesktop.org>
> > >Subject: Re: [PATCH v4 3/7] drm: Add DisplayPort colorspace property
> > >
> > >So how would this work with a DP++ connector? Should it list the HDMI or DP
> > >properties? Or do we need a custom property checker which is aware of what is
> > >currently plugged in to validate the values?
> >
> > AFAIU For DP++ cases, we detect what kind of sink its driving DP or HDMI (with a passive dongle).
> > Based on the type of sink detected, we should expose DP or HDMI colorspaces to userspace.
>
> For i915 DP connector always drives DP mode, HDMI connector always drives
> HDMI mode, even when the physical connector is DP++.

Right, i915 creates 2 connectors, while nouveau, radeon, and amdgpu
create 1 connector (not sure about other drivers) for a single
physical DP++ socket. Since we supply the list of valid values at the
time of creating the connector, we can't know at that point whether in
the future a HDMI or DP will be plugged into it.

  -ilia