diff --git a/drivers/isdn/hisax/hfcscard.c b/drivers/isdn/hisax/hfcscard.c
index 6fc55fe..86ab1c1 100644
--- a/drivers/isdn/hisax/hfcscard.c
+++ b/drivers/isdn/hisax/hfcscard.c
@@ -52,7 +52,7 @@
 */
 }
 
-void
+static void
 release_io_hfcs(struct IsdnCardState *cs)
 {
 	release2bds0(cs);