diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
index 6f15069da8b0..0c2f976516a4 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -367,11 +367,6 @@ void mtk_ovl_layer_off(struct device *dev, unsigned int idx,
 
 static unsigned int ovl_fmt_convert(struct mtk_disp_ovl *ovl, unsigned int fmt)
 {
-	/* The return value in switch "MEM_MODE_INPUT_FORMAT_XXX"
-	 * is defined in mediatek HW data sheet.
-	 * The alphabet order in XXX is no relation to data
-	 * arrangement in memory.
-	 */
 	switch (fmt) {
 	default:
 	case DRM_FORMAT_RGB565: