[PATCH v14 17/28] drm/connector: hdmi: Add Broadcast RGB property

[Dmitry Baryshkov]

On Mon, May 27, 2024 at 11:02:13AM +0200, Maxime Ripard wrote:
> Hi,
> 
> Thanks again for that thorough review :)
> 
> On Thu, May 23, 2024 at 01:22:56PM GMT, Dmitry Baryshkov wrote:
> > On Tue, May 21, 2024 at 12:13:50PM +0200, Maxime Ripard wrote:
> > > The i915 driver has a property to force the RGB range of an HDMI output.
> > > The vc4 driver then implemented the same property with the same
> > > semantics. KWin has support for it, and a PR for mutter is also there to
> > > support it.
> > > 
> > > Both drivers implementing the same property with the same semantics,
> > > plus the userspace having support for it, is proof enough that it's
> > > pretty much a de-facto standard now and we can provide helpers for it.
> > > 
> > > Let's plumb it into the newly created HDMI connector.
> > > 
> > > Reviewed-by: Dave Stevenson <dave.stevenson at raspberrypi.com>
> > > Acked-by: Pekka Paalanen <pekka.paalanen at collabora.com>
> > > Reviewed-by: Sebastian Wick <sebastian.wick at redhat.com>
> > > Signed-off-by: Maxime Ripard <mripard at kernel.org>
> > > ---
> > >  Documentation/gpu/kms-properties.csv            |  1 -
> > >  drivers/gpu/drm/display/drm_hdmi_state_helper.c |  4 +-
> > >  drivers/gpu/drm/drm_atomic.c                    |  2 +
> > >  drivers/gpu/drm/drm_atomic_uapi.c               |  4 ++
> > >  drivers/gpu/drm/drm_connector.c                 | 88 +++++++++++++++++++++++++
> > >  include/drm/drm_connector.h                     | 36 ++++++++++
> > >  6 files changed, 133 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/Documentation/gpu/kms-properties.csv b/Documentation/gpu/kms-properties.csv
> > > index 0f9590834829..caef14c532d4 100644
> > > --- a/Documentation/gpu/kms-properties.csv
> > > +++ b/Documentation/gpu/kms-properties.csv
> > > @@ -15,11 +15,10 @@ Owner Module/Drivers,Group,Property Name,Type,Property Values,Object attached,De
> > >  ,,“saturation”,RANGE,"Min=0, Max=100",Connector,TBD
> > >  ,,“hue”,RANGE,"Min=0, Max=100",Connector,TBD
> > >  ,Virtual GPU,“suggested X”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an X offset for a connector
> > >  ,,“suggested Y”,RANGE,"Min=0, Max=0xffffffff",Connector,property to suggest an Y offset for a connector
> > >  ,Optional,"""aspect ratio""",ENUM,"{ ""None"", ""4:3"", ""16:9"" }",Connector,TDB
> > > -i915,Generic,"""Broadcast RGB""",ENUM,"{ ""Automatic"", ""Full"", ""Limited 16:235"" }",Connector,"When this property is set to Limited 16:235 and CTM is set, the hardware will be programmed with the result of the multiplication of CTM by the limited range matrix to ensure the pixels normally in the range 0..1.0 are remapped to the range 16/255..235/255."
> > 
> > Should it still be defined as a generic property?
> 
> I'm not sure what you mean here, sorry. It's being documented as a
> connector property now, so it's very much still listed as a generic
> property?

I didn't perform my duty well enough and I didn't check the file for
other instances of the property. Now I indeed see a generic "Broadcast
RGB" property, but to me it looks like having a different set of values:

,,"""Broadcast RGB""",ENUM,"{ “off”, “auto”, “on” }",Connector,TBD

-- 
With best wishes
Dmitry