diff --git a/board/Synology/ds109/ds109.c b/board/Synology/ds109/ds109.c
index c4cd95c..aa2987d 100644
--- a/board/Synology/ds109/ds109.c
+++ b/board/Synology/ds109/ds109.c
@@ -13,6 +13,7 @@
 #include <asm/arch/cpu.h>
 #include <asm/arch/soc.h>
 #include <asm/arch/mpp.h>
+#include <linux/delay.h>
 #include "ds109.h"
 
 DECLARE_GLOBAL_DATA_PTR;