Re: [PATCH] drm/i915/hdcp: Skip inactive MST connectors when building stream list

["Reddy Guddati, Santhosh" <santhosh.reddy.guddati@intel.com>]

Hi Suraj,

On 05-05-2026 15:10, Suraj Kandpal wrote:
> intel_hdcp_required_content_stream() walks every connector on the
> digital port to populate hdcp_port_data->streams[]. The only filter is
> connector_status_disconnected, which reflects physical presence on the
> MST topology, not whether the connector currently drives a stream.
> On a multi-sink MST setup where only a subset of sinks are modeset,
> the loop can pick a sibling MST connector that is connected but has
> no active CRTC / VC payload. intel_conn_to_vcpi() then logs "MST
> Payload not present" and returns 0, and the bogus StreamID=0 is
> written to the repeater in RepeaterAuth_Stream_Manage (DPCD 0x693F0).
> Authentication completes, but the repeater shortly raises
> LINK_INTEGRITY_FAILURE (RxStatus 0x69493 bit4) because the StreamID
> does not match any stream on its input. The HDCP check work then
> tears the link down, the Content Protection property drops back to
> DESIRED, and userspace observes a spurious HDCP enable failure.
> Filter the connector iteration to only those with a CRTC assigned in
> the new atomic state, so intel_conn_to_vcpi() is called for the
> connector actually being enabled and reads its real VCPI from the MST
> topology state.
> 
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_hdcp.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index 982f698e9814..1b2e2727c14c 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -116,6 +116,7 @@ intel_hdcp_required_content_stream(struct intel_atomic_state *state,
>   	struct intel_digital_port *conn_dig_port;
>   	struct intel_connector *connector;
>   	struct hdcp_port_data *data = &dig_port->hdcp.port_data;
> +	struct drm_connector_state *new_conn_state;
>   	bool enforce_type0 = false;
>   	int k;
>   
> @@ -139,6 +140,11 @@ intel_hdcp_required_content_stream(struct intel_atomic_state *state,
>   		if (conn_dig_port != dig_port)
>   			continue;
>   
> +		new_conn_state = drm_atomic_get_new_connector_state(&state->base,
> +								    &connector->base);
> +		if (!new_conn_state || !new_conn_state->crtc)
> +			continue;
> +
LGTM
Reviewed-by: Santhosh Reddy Guddati <santhosh.reddy.guddati@intel.com>
>   		data->streams[data->k].stream_id =
>   			intel_conn_to_vcpi(state, connector);
>   		data->k++;