diff --git a/drivers/tty/hvc/hvc_udbg.c b/drivers/tty/hvc/hvc_udbg.c
index a4c9913f76a0..ff0dcc56413c 100644
--- a/drivers/tty/hvc/hvc_udbg.c
+++ b/drivers/tty/hvc/hvc_udbg.c
@@ -17,7 +17,7 @@
 
 #include "hvc_console.h"
 
-struct hvc_struct *hvc_udbg_dev;
+static struct hvc_struct *hvc_udbg_dev;
 
 static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
 {