diff --git a/drivers/isdn/hisax/ipacx.c b/drivers/isdn/hisax/ipacx.c
index 00afd55..751b25f 100644
--- a/drivers/isdn/hisax/ipacx.c
+++ b/drivers/isdn/hisax/ipacx.c
@@ -10,6 +10,7 @@
  *
  */
 #include <linux/kernel.h>
+#include <linux/slab.h>
 #include <linux/init.h>
 #include "hisax_if.h"
 #include "hisax.h"