[PATCH 3/4] drm/i915/dp_mst: Expose a connector to kernel users after it's properly initialized

[Imre Deak]

On Mon, Nov 18, 2024 at 02:12:14PM +0200, Jani Nikula wrote:
> On Fri, 15 Nov 2024, Imre Deak <imre.deak at intel.com> wrote:
> > After a connector is added to the drm_mode_config::connector_list, it's
> > visible to any in-kernel users looking up connectors via the above list.
> > Make sure that the connector is properly initialized before such
> > look-ups.
> >
> > Signed-off-by: Imre Deak <imre.deak at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_dp_mst.c | 29 ++++++++-------------
> >  1 file changed, 11 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > index f058360a26413..d91a1d1fb26f4 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > @@ -1719,6 +1719,8 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
> >  	if (!intel_connector)
> >  		return NULL;
> >  
> > +	connector = &intel_connector->base;
> 
> I'd rather see a patch s/intel_connector/connector/ and using
> &connector->base for drm_connector.

Yes, thought the same and did it. However I think that should be done
converting all the other intel_connector usage in the file. Is that ok
with you?

> 
> > +
> >  	intel_connector->get_hw_state = intel_dp_mst_get_hw_state;
> >  	intel_connector->sync_state = intel_dp_connector_sync_state;
> >  	intel_connector->mst_port = intel_dp;
> > @@ -1727,30 +1729,19 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
> >  
> >  	intel_dp_init_modeset_retry_work(intel_connector);
> >  
> > -	/*
> > -	 * TODO: The following drm_connector specific initialization belongs
> > -	 * to DRM core, however it happens atm too late in
> > -	 * drm_connector_init(). That function will also expose the connector
> > -	 * to in-kernel users, so it can't be called until the connector is
> > -	 * sufficiently initialized; init the device pointer used by the
> > -	 * following DSC setup, until a fix moving this to DRM core.
> > -	 */
> > -	intel_connector->base.dev = mgr->dev;
> > -
> > -	intel_connector->dp.dsc_decompression_aux = drm_dp_mst_dsc_aux_for_port(port);
> > -	intel_dp_mst_read_decompression_port_dsc_caps(intel_dp, intel_connector);
> > -	intel_connector->dp.dsc_hblank_expansion_quirk =
> > -		detect_dsc_hblank_expansion_quirk(intel_connector);
> > -
> > -	connector = &intel_connector->base;
> > -	ret = drm_connector_init(display->drm, connector, &intel_dp_mst_connector_funcs,
> > -				 DRM_MODE_CONNECTOR_DisplayPort);
> > +	ret = drm_connector_init_core(display->drm, connector, &intel_dp_mst_connector_funcs,
> > +				      DRM_MODE_CONNECTOR_DisplayPort);
> >  	if (ret) {
> >  		drm_dp_mst_put_port_malloc(port);
> >  		intel_connector_free(intel_connector);
> >  		return NULL;
> >  	}
> >  
> > +	intel_connector->dp.dsc_decompression_aux = drm_dp_mst_dsc_aux_for_port(port);
> > +	intel_dp_mst_read_decompression_port_dsc_caps(intel_dp, intel_connector);
> > +	intel_connector->dp.dsc_hblank_expansion_quirk =
> > +		detect_dsc_hblank_expansion_quirk(intel_connector);
> > +
> >  	drm_connector_helper_add(connector, &intel_dp_mst_connector_helper_funcs);
> >  
> >  	for_each_pipe(display, pipe) {
> > @@ -1771,6 +1762,8 @@ static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
> >  		drm_dbg_kms(display->drm, "[%s:%d] HDCP MST init failed, skipping.\n",
> >  			    connector->name, connector->base.id);
> >  
> > +	drm_connector_add(connector);
> > +
> >  	return connector;
> >  
> >  err:
> 
> -- 
> Jani Nikula, Intel