[PATCH] drm/atomic-helper: Check encoder/crtc constraints

[Daniel Vetter]

On Thu, Nov 19, 2015 at 12:12:28PM +0200, Ville Syrjälä wrote:
> On Wed, Nov 18, 2015 at 06:46:48PM +0100, Daniel Vetter wrote:
> > This was totally lost when I originally created the atomic helpers.
> > 
> > We probably should also check possible_clones in the helpers, but
> > since the legacy ones didn't do that this is for a separate patch.
> > 
> > Reported-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Daniel Stone <daniels at collabora.com>
> > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> 
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Tested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> But the rest of update_connector_routing() still looks somewhat bonkers
> to me. For one, it assumes that both the old and new crtc for the
> connector are part of the atomic state, but drm_atomic_set_crtc_for_connector()
> only adds the new crtc, not the old one.

Nothing bonkers about it since drm_atomic_get_connector_state ensures that
the corresponding crtc state is part of the update. Same logic applies for
planes.
-Daniel

> 
> > ---
> >  drivers/gpu/drm/drm_atomic_helper.c | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> > index 0c6f62168776..cfdc9931b08a 100644
> > --- a/drivers/gpu/drm/drm_atomic_helper.c
> > +++ b/drivers/gpu/drm/drm_atomic_helper.c
> > @@ -210,6 +210,14 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx)
> >  		return -EINVAL;
> >  	}
> >  
> > +	if (!drm_encoder_crtc_ok(new_encoder, connector_state->crtc)) {
> > +		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] incompatible with [CRTC:%d]\n",
> > +				 new_encoder->base.id,
> > +				 new_encoder->name,
> > +				 connector_state->crtc->base.id);
> > +		return -EINVAL;
> > +	}
> > +
> >  	if (new_encoder == connector_state->best_encoder) {
> >  		DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] keeps [ENCODER:%d:%s], now on [CRTC:%d]\n",
> >  				 connector->base.id,
> > -- 
> > 2.5.1
> 
> -- 
> Ville Syrjälä
> Intel OTC

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch