diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c
index 4c203d013d7c..a0b526b16da1 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c
@@ -77,6 +77,7 @@
 #define MUTEX_SOF_DSI1			2
 #define MUTEX_SOF_DPI0			3
 #define MUTEX_SOF_DPI1			4
+#define MUTEX_SOF_DSI2			5
 
 #define OVL0_MOUT_EN_COLOR0		0x1
 #define OD_MOUT_EN_RDMA0		0x1
@@ -383,6 +384,9 @@ void mtk_disp_mutex_add_comp(struct mtk_disp_mutex *mutex,
 	case DDP_COMPONENT_DSI1:
 		reg = MUTEX_SOF_DSI0;
 		break;
+	case DDP_COMPONENT_DSI2:
+		reg = MUTEX_SOF_DSI2;
+		break;
 	case DDP_COMPONENT_DPI0:
 		reg = MUTEX_SOF_DPI0;
 		break;
@@ -420,6 +424,7 @@ void mtk_disp_mutex_remove_comp(struct mtk_disp_mutex *mutex,
 	switch (id) {
 	case DDP_COMPONENT_DSI0:
 	case DDP_COMPONENT_DSI1:
+	case DDP_COMPONENT_DSI2:
 	case DDP_COMPONENT_DPI0:
 	case DDP_COMPONENT_DPI1:
 		writel_relaxed(MUTEX_SOF_SINGLE_MODE,