diff --git a/drivers/watchdog/nuc900_wdt.c b/drivers/watchdog/nuc900_wdt.c
index 50359bad9177..2cce8568bd21 100644
--- a/drivers/watchdog/nuc900_wdt.c
+++ b/drivers/watchdog/nuc900_wdt.c
@@ -72,7 +72,7 @@ struct nuc900_wdt {
 };
 
 static unsigned long nuc900wdt_busy;
-struct nuc900_wdt *nuc900_wdt;
+static struct nuc900_wdt *nuc900_wdt;
 
 static inline void nuc900_wdt_keepalive(void)
 {