1 files changed, 31 insertions, 23 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 631fd1537252..c8e2215628e6 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -41,8 +41,12 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 	struct drm_connector *connector = conn_state->connector;
 	void *port = to_intel_connector(connector)->port;
 	struct drm_atomic_state *state = pipe_config->base.state;
+	struct drm_crtc *crtc = pipe_config->base.crtc;
+	struct drm_crtc_state *old_crtc_state =
+		drm_atomic_get_old_crtc_state(state, crtc);
 	int bpp;
-	int lane_count, slots = 0;
+	int lane_count, slots =
+		to_intel_crtc_state(old_crtc_state)->dp_m_n.tu;
 	const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
 	int mst_pbn;
 	bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
@@ -107,35 +111,39 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 	return true;
 }
 
-static int intel_dp_mst_atomic_check(struct drm_connector *connector,
-		struct drm_connector_state *new_conn_state)
+static int
+intel_dp_mst_atomic_check(struct drm_connector *connector,
+			  struct drm_connector_state *new_conn_state)
 {
 	struct drm_atomic_state *state = new_conn_state->state;
-	struct drm_connector_state *old_conn_state;
-	struct drm_crtc *old_crtc;
+	struct drm_connector_state *old_conn_state =
+		drm_atomic_get_old_connector_state(state, connector);
+	struct intel_connector *intel_connector =
+		to_intel_connector(connector);
+	struct drm_crtc *new_crtc = new_conn_state->crtc;
 	struct drm_crtc_state *crtc_state;
-	int slots, ret = 0;
+	struct drm_dp_mst_topology_mgr *mgr;
+	int ret = 0;
 
-	old_conn_state = drm_atomic_get_old_connector_state(state, connector);
-	old_crtc = old_conn_state->crtc;
-	if (!old_crtc)
-		return ret;
-
-	crtc_state = drm_atomic_get_new_crtc_state(state, old_crtc);
-	slots = to_intel_crtc_state(crtc_state)->dp_m_n.tu;
-	if (drm_atomic_crtc_needs_modeset(crtc_state) && slots > 0) {
-		struct drm_dp_mst_topology_mgr *mgr;
-		struct drm_encoder *old_encoder;
+	if (!old_conn_state->crtc)
+		return 0;
 
-		old_encoder = old_conn_state->best_encoder;
-		mgr = &enc_to_mst(old_encoder)->primary->dp.mst_mgr;
+	/* We only want to free VCPI if this state disables the CRTC on this
+	 * connector
+	 */
+	if (new_crtc) {
+		crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc);
 
-		ret = drm_dp_atomic_release_vcpi_slots(state, mgr, slots);
-		if (ret)
-			DRM_DEBUG_KMS("failed releasing %d vcpi slots:%d\n", slots, ret);
-		else
-			to_intel_crtc_state(crtc_state)->dp_m_n.tu = 0;
+		if (!crtc_state ||
+		    !drm_atomic_crtc_needs_modeset(crtc_state) ||
+		    crtc_state->enable)
+			return 0;
 	}
+
+	mgr = &enc_to_mst(old_conn_state->best_encoder)->primary->dp.mst_mgr;
+	ret = drm_dp_atomic_release_vcpi_slots(state, mgr,
+					       intel_connector->port);
+
 	return ret;
 }