[Intel-gfx] [PATCH 2/2] drm/i915/dp_mst: don't pull unregistered connectors into state

[Simon Ser <contact@emersion.fr>]

In intel_dp_mst_atomic_master_trans_check(), we pull connectors
sharing the same DP-MST stream into the atomic state. However,
if the connector is unregistered, this later fails with:

    [  559.425658] i915 0000:00:02.0: [drm:drm_atomic_helper_check_modeset] [CONNECTOR:378:DP-7] is not registered

Skip these unregistered connectors to allow user-space to turn them
off.

Fixes part of this wlroots issue:
https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/3407

Signed-off-by: Simon Ser <contact@emersion.fr>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Lyude Paul <lyude@redhat.com>
---
 drivers/gpu/drm/i915/display/intel_dp_mst.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index f773e117ebc4..70859a927a9d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -280,7 +280,8 @@ intel_dp_mst_atomic_master_trans_check(struct intel_connector *connector,
 		struct intel_crtc *crtc;
 
 		if (connector_iter->mst_port != connector->mst_port ||
-		    connector_iter == connector)
+		    connector_iter == connector ||
+		    connector_iter->base.registration_state == DRM_CONNECTOR_UNREGISTERED)
 			continue;
 
 		conn_iter_state = intel_atomic_get_digital_connector_state(state,
-- 
2.39.0