diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
index aabe9d58c3dc..b04fa9fd90b7 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_connectors.c
@@ -1231,6 +1231,8 @@ static enum drm_mode_status amdgpu_connector_dvi_mode_valid(struct drm_connector
 		case CONNECTOR_OBJECT_ID_HDMI_TYPE_B:
 			max_digital_pixel_clock_khz = max_dvi_single_link_pixel_clock * 2;
 			break;
+		default:
+			return MODE_BAD;
 		}
 
 		/* When the display EDID claims that it's an HDMI display,