Re: [PATCH 4/4] drm/atomic-helper: Add select_output_bus_format callback

[Maxime Ripard]

Hi,

On Wed, Feb 28, 2024 at 10:00:19PM +0000, Klymenko, Anatoliy wrote:
> > > diff --git a/include/drm/drm_modeset_helper_vtables.h
> > > b/include/drm/drm_modeset_helper_vtables.h
> > > index 881b03e4dc28..7c21ae1fe3ad 100644
> > > --- a/include/drm/drm_modeset_helper_vtables.h
> > > +++ b/include/drm/drm_modeset_helper_vtables.h
> > > @@ -489,6 +489,37 @@ struct drm_crtc_helper_funcs {
> > >  				     bool in_vblank_irq, int *vpos, int *hpos,
> > >  				     ktime_t *stime, ktime_t *etime,
> > >  				     const struct drm_display_mode *mode);
> > > +
> > > +	/**
> > > +	 * @select_output_bus_format
> > > +	 *
> > > +	 * Called by the first connected DRM bridge to negotiate input media
> > > +	 * bus format. CRTC is expected to pick preferable media formats from
> > > +	 * the list supported by the DRM bridge chain.
> > 
> > There's nothing restricting it to bridges here. Please rephrase this to remove the
> > bridge mention. The user is typically going to be the encoder, and bridges are just
> > an automagic implementation of an encoder.
> > 
> 
> OK. I'll fix than in the next version.
> 
> > And generally speaking, I'd really like to have an implementation available before
> > merging this.
> >
> 
> Well, 2 instances of this callback implementations exist as drafts, as
> this is the new API. A little bit of a chicken and egg problem. I'll
> try to groom at least one of them into upstreamable shape and attach
> it to the patch set.

That's totally what I meant :)

I basically don't want to have an interface that isn't used. If you
provide an implementation in the same series, it's totally reasonable

Maxime

Attachment: signature.asc
Description: PGP signature