diff --git a/drivers/net/slip.c b/drivers/net/slip.c
index 16363b5..404ea42 100644
--- a/drivers/net/slip.c
+++ b/drivers/net/slip.c
@@ -74,6 +74,7 @@
 #include <linux/rtnetlink.h>
 #include <linux/if_arp.h>
 #include <linux/if_slip.h>
+#include <linux/delay.h>
 #include <linux/init.h>
 #include "slip.h"
 #ifdef CONFIG_INET