Re: [PATCH 1/2] drm/915/hdcp: Use new MST topology state in intel_conn_to_vcpi()

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

Hi Suraj,

fix typo in commit message /drm/915 to drm/i915.

On 30-04-2026 08:59, Suraj Kandpal wrote:
> intel_conn_to_vcpi() runs from the HDCP enable path in commit_tail
> and looks up the VCPI via mgr->base.state. When an ALLOCATE_PAYLOAD
> is being driven on the mgr just before HDCP enable, that payload
> list is being mutated in place, so the lookup can miss the port and
> trip drm_WARN_ON(!payload), causing HDCP to be programmed with
> VCPI 0.
> Use drm_atomic_get_new_mst_topology_state() to read the topology
> state attached to this atomic commit (stable, decided in
> atomic_check), and bail out cleanly when no topology state or
> payload is present for this port instead of WARNing.
> 
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_hdcp.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index 9b4ff3b80b05..91d2d7d823cc 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -72,6 +72,7 @@ intel_hdcp_adjust_hdcp_line_rekeying(struct intel_encoder *encoder,
>   static int intel_conn_to_vcpi(struct intel_atomic_state *state,
>   			      struct intel_connector *connector)
>   {
> +	struct intel_display *display = to_intel_display(state);
>   	struct drm_dp_mst_topology_mgr *mgr;
>   	struct drm_dp_mst_atomic_payload *payload;
>   	struct drm_dp_mst_topology_state *mst_state;
> @@ -82,9 +83,14 @@ static int intel_conn_to_vcpi(struct intel_atomic_state *state,
>   	mgr = connector->mst.port->mgr;
>   
>   	drm_modeset_lock(&mgr->base.lock, state->base.acquire_ctx);
> -	mst_state = to_drm_dp_mst_topology_state(mgr->base.state);
> +	mst_state = drm_atomic_get_new_mst_topology_state(&state->base, mgr);
> +	if (!mst_state) {
> +		drm_dbg_kms(display->drm, "MST topology still not created\n");
> +		return 0;
> +	}
> +
>   	payload = drm_atomic_get_mst_payload_state(mst_state, connector->mst.port);
> -	if (drm_WARN_ON(mgr->dev, !payload))
> +	if (!payload)
     is it good to have a debug message here to trace payload in mst 
state. Rest LGTM.

Tested-by: Santhosh Reddy Guddati <santhosh.reddy.guddati@intel.com>
Reviewed-by: Santhosh Reddy Guddati <santhosh.reddy.guddati@intel.com>
>   		return 0;
>   
>   	return payload->vcpi;