[Intel-gfx] [v6 03/11] drm/i915/display: Attach HDR property for capable Gen9 devices

[Ville Syrjälä]

On Mon, Oct 05, 2020 at 09:32:22PM +0000, Shankar, Uma wrote:
> 
> 
> > -----Original Message-----
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Sent: Tuesday, September 29, 2020 9:44 PM
> > To: Shankar, Uma <uma.shankar at intel.com>
> > Cc: intel-gfx at lists.freedesktop.org
> > Subject: Re: [v6 03/11] drm/i915/display: Attach HDR property for capable Gen9
> > devices
> > 
> > On Tue, Sep 15, 2020 at 02:30:39AM +0530, Uma Shankar wrote:
> > > Attach HDR property for Gen9 devices with MCA LSPCON chips.
> > >
> > > v2: Cleaned HDR property attachment logic based on capability as per
> > > Jani Nikula's suggestion.
> > >
> > > Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_lspcon.c | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.c
> > > b/drivers/gpu/drm/i915/display/intel_lspcon.c
> > > index 5e2d7ca1d20f..fd05210f4405 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_lspcon.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_lspcon.c
> > > @@ -626,6 +626,11 @@ bool lspcon_init(struct intel_digital_port
> > > *dig_port)
> > >
> > >  	lspcon_detect_hdr_capability(lspcon);
> > >
> > > +	if (lspcon->hdr_supported)
> > > +		drm_object_attach_property(&connector->base,
> > > +					   connector->dev-
> > >mode_config.hdr_output_metadata_property,
> > > +					   0);
> > 
> > Hmm. This hdr capability detection is going to cause us extra grief when looking
> > at Kai-Heng's patch to defer lspcon detection until hotplug time. Not quite sure
> > what to do about that though.
> 
> Yeah Ville, saw your comments and with Kai's change merge, I am thinking how to attach
> this dynamically. 

Not allowed. 

> 
> Can we just assume that Lspcon will support HDR as is the case in Gen9. We can just attach this
> unconditionally at init if Lspcon is exposed from VBT. Will this be acceptable or Any better ideas ?

I have no idea what these lspcon chips supports since -ENODOCS.

The only idea I have is to attempt an early probe for this, and if it
fails on some chips due to hpd not being asserted so be it.

>  
> > > +
> > >  	connector->ycbcr_420_allowed = true;
> > >  	lspcon->active = true;
> > >  	DRM_DEBUG_KMS("Success: LSPCON init\n");
> > > --
> > > 2.26.2
> > 
> > --
> > Ville Syrjälä
> > Intel

-- 
Ville Syrjälä
Intel