diff --git a/bsp/src/bsp_button.c b/bsp/src/bsp_button.c
index b9f2a59..d5089e0 100644
--- a/bsp/src/bsp_button.c
+++ b/bsp/src/bsp_button.c
@@ -88,6 +88,7 @@ static void _BUTTON_Process(void *param)
 
 int BSP_BUTTON_Init(void)
 {
+    rt_err_t ret = RT_EOK;
     rt_memset(&user_button[0], 0x0, sizeof(user_button));
 
     rt_pin_mode(BUTTON_0, PIN_MODE_INPUT_PULLUP); /* set KEY pin mode to input */