diff --git a/include/linux/isdn_divertif.h b/include/linux/isdn_divertif.h
index 07821ca5955f..a5a50f523807 100644
--- a/include/linux/isdn_divertif.h
+++ b/include/linux/isdn_divertif.h
@@ -10,6 +10,8 @@
  *
  */
 
+#ifndef _LINUX_ISDN_DIVERTIF_H
+#define _LINUX_ISDN_DIVERTIF_H
 
 /***********************************************************/
 /* magic value is also used to control version information */
@@ -45,3 +47,5 @@ typedef struct
 /*********************/
 extern int DIVERT_REG_NAME(isdn_divert_if *);
 #endif
+
+#endif /* _LINUX_ISDN_DIVERTIF_H */