diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 4c4f976c994e..3305a94fc930 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -215,11 +215,12 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
 	struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
 	struct mtk_ddp_comp *comp;
 	int i, count = 0;
+	unsigned int local_index = plane - mtk_crtc->planes;
 
 	for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
 		comp = mtk_crtc->ddp_comp[i];
-		if (plane->index < (count + mtk_ddp_comp_layer_nr(comp))) {
-			*local_layer = plane->index - count;
+		if (local_index < (count + mtk_ddp_comp_layer_nr(comp))) {
+			*local_layer = local_index - count;
 			return comp;
 		}
 		count += mtk_ddp_comp_layer_nr(comp);