diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 32f6f57fc66ea79c718eea093f8f31c5b804ff2b..9fab9860999b35359be6fd942bb9d812a3683886 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -86,6 +86,68 @@ drm_atomic_helper_plane_changed(struct drm_atomic_state *state,
 	}
 }
 
+static int disable_conflicting_connectors(struct drm_atomic_state *state)
+{
+	struct drm_connector_state *conn_state;
+	struct drm_connector *connector;
+	struct drm_encoder *encoder;
+	unsigned encoder_mask = 0;
+	int i, ret;
+
+	for_each_connector_in_state(state, connector, conn_state, i) {
+		const struct drm_connector_helper_funcs *funcs = connector->helper_private;
+		struct drm_encoder *new_encoder;
+
+		if (!conn_state->crtc)
+			continue;
+
+		if (funcs->atomic_best_encoder)
+			new_encoder = funcs->atomic_best_encoder(connector, conn_state);
+		else
+			new_encoder = funcs->best_encoder(connector);
+
+		if (new_encoder)
+			encoder_mask |= 1 << drm_encoder_index(new_encoder);
+	}
+
+	drm_for_each_connector(connector, state->dev) {
+		struct drm_crtc_state *crtc_state;
+
+		if (drm_atomic_get_existing_connector_state(state, connector))
+			continue;
+
+		encoder = connector->state->best_encoder;
+		if (!encoder || !(encoder_mask & (1 << drm_encoder_index(encoder))))
+			continue;
+
+		conn_state = drm_atomic_get_connector_state(state, connector);
+		if (IS_ERR(conn_state))
+			return PTR_ERR(conn_state);
+
+		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], disabling [CONNECTOR:%d:%s]\n",
+				 encoder->base.id, encoder->name,
+				 conn_state->crtc->base.id, conn_state->crtc->name,
+				 connector->base.id, connector->name);
+
+		crtc_state = drm_atomic_get_existing_crtc_state(state, conn_state->crtc);
+
+		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
+		if (ret)
+			return ret;
+
+		if (!crtc_state->connector_mask) {
+			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
+								NULL);
+			if (ret < 0)
+				return ret;
+
+			crtc_state->active = false;
+		}
+	}
+
+	return 0;
+}
+
 static bool
 check_pending_encoder_assignment(struct drm_atomic_state *state,
 				 struct drm_encoder *new_encoder)
@@ -448,6 +510,12 @@ drm_atomic_helper_check_modeset(struct drm_device *dev,
 		}
 	}
 
+	if (state->legacy_set_config) {
+		ret = disable_conflicting_connectors(state);
+		if (ret)
+			return ret;
+	}
+
 	for_each_connector_in_state(state, connector, connector_state, i) {
 		/*
 		 * This only sets crtc->mode_changed for routing changes,
@@ -1796,6 +1864,7 @@ int drm_atomic_helper_set_config(struct drm_mode_set *set)
 	if (!state)
 		return -ENOMEM;
 
+	state->legacy_set_config = true;
 	state->acquire_ctx = drm_modeset_legacy_acquire_ctx(crtc);
 retry:
 	ret = __drm_atomic_helper_set_config(set, state);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8c7fb3d0f9d0f621bea427be0462cbb27ba51d1a..75b28deeaf2458d313e5655e8290c5026edcc0bb 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1676,6 +1676,7 @@ struct drm_bridge {
  * @dev: parent DRM device
  * @allow_modeset: allow full modeset
  * @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
+ * @legacy_set_config: Disable conflicting encoders instead of failing with -EINVAL.
  * @planes: pointer to array of plane pointers
  * @plane_states: pointer to array of plane states pointers
  * @crtcs: pointer to array of CRTC pointers
@@ -1689,6 +1690,7 @@ struct drm_atomic_state {
 	struct drm_device *dev;
 	bool allow_modeset : 1;
 	bool legacy_cursor_update : 1;
+	bool legacy_set_config : 1;
 	struct drm_plane **planes;
 	struct drm_plane_state **plane_states;
 	struct drm_crtc **crtcs;