Re: [PATCH RESEND v9 3/6] drm/bridge: cadence: cdns-mhdp8546-core: Handle HDCP state in bridge atomic check

[Harikrishna shenoy]

On 21/11/25 18:16, Tomi Valkeinen wrote:
> Hi,
>
> On 20/11/2025 14:14, Harikrishna Shenoy wrote:
> > Now that we have DRM_BRIDGE_ATTACH_NO_CONNECTOR framework, handle the
> > HDCP state change inbridge atomic check as well to enable correct
>
> "in bridge's"
>
> > functioning for HDCP in both DRM_BRIDGE_ATTACH_NO_CONNECTOR and
> > !DRM_BRIDGE_ATTACH_NO_CONNECTOR case.
>
> Same thing here. What is the issue? What behavior do you see without
> this patch?
>
>   Tomi
Hi Tomi,

This patch update the HDCP state in bridge hooks, as connector hooks
are not used with DBANC, so essentially helps correct functioning of 
HDCP by updating its state.

Regards.
> > Fixes: 6a3608eae6d33 ("drm: bridge: cdns-mhdp8546: Enable HDCP")
> > Signed-off-by: Harikrishna Shenoy <h-shenoy@xxxxxx>
> > ---
> >   .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 23 +++++++++++++++++++
> >   1 file changed, 23 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> > index 7178a01e4d4d8..d944095da4722 100644
> > --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> > @@ -2123,6 +2123,10 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
> >   {
> >   	struct cdns_mhdp_device *mhdp = bridge_to_mhdp(bridge);
> >   	const struct drm_display_mode *mode = &crtc_state->adjusted_mode;
> > +	struct drm_connector_state *old_state, *new_state;
> > +	struct drm_atomic_state *state = crtc_state->state;
> > +	struct drm_connector *conn = mhdp->connector_ptr;
> > +	u64 old_cp, new_cp;
> >   
> >   	mutex_lock(&mhdp->link_mutex);
> >   
> > @@ -2142,6 +2146,25 @@ static int cdns_mhdp_atomic_check(struct drm_bridge *bridge,
> >   	if (mhdp->info)
> >   		bridge_state->input_bus_cfg.flags = *mhdp->info->input_bus_flags;
> >   
> > +	if (conn && mhdp->hdcp_supported) {
> > +		old_state = drm_atomic_get_old_connector_state(state, conn);
> > +		new_state = drm_atomic_get_new_connector_state(state, conn);
> > +		old_cp = old_state->content_protection;
> > +		new_cp = new_state->content_protection;
> > +
> > +		if (old_state->hdcp_content_type != new_state->hdcp_content_type &&
> > +		    new_cp != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) {
> > +			new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> > +			crtc_state = drm_atomic_get_new_crtc_state(state, new_state->crtc);
> > +			crtc_state->mode_changed = true;
> > +		}
> > +
> > +		if (!new_state->crtc) {
> > +			if (old_cp == DRM_MODE_CONTENT_PROTECTION_ENABLED)
> > +				new_state->content_protection = DRM_MODE_CONTENT_PROTECTION_DESIRED;
> > +		}
> > +	}
> > +
> >   	mutex_unlock(&mhdp->link_mutex);
> >   	return 0;
> >   }