diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c
index 237b67de62c1..0c96f9d15279 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_dc_resource_mgmt.c
@@ -88,7 +88,8 @@ static int find_disp_cfg_idx_by_plane_id(struct dml2_dml_to_dc_pipe_mapping *map
 			return  i;
 	}
 
-	return -1;
+	ASSERT(false);
+	return __DML2_WRAPPER_MAX_STREAMS_PLANES__;
 }
 
 static int find_disp_cfg_idx_by_stream_id(struct dml2_dml_to_dc_pipe_mapping *mapping, unsigned int stream_id)
@@ -100,7 +101,8 @@ static int find_disp_cfg_idx_by_stream_id(struct dml2_dml_to_dc_pipe_mapping *ma
 			return  i;
 	}
 
-	return -1;
+	ASSERT(false);
+	return __DML2_WRAPPER_MAX_STREAMS_PLANES__;
 }
 
 // The master pipe of a stream is defined as the top pipe in odm slice 0