diff --git a/drivers/isdn/hardware/avm/c4.c b/drivers/isdn/hardware/avm/c4.c
index 724aac2..f7253b2 100644
--- a/drivers/isdn/hardware/avm/c4.c
+++ b/drivers/isdn/hardware/avm/c4.c
@@ -50,7 +50,7 @@
 MODULE_DESCRIPTION("CAPI4Linux: Driver for AVM C2/C4 cards");
 MODULE_AUTHOR("Carsten Paeth");
 MODULE_LICENSE("GPL");
-MODULE_PARM(suppress_pollack, "0-1i");
+module_param(suppress_pollack, bool, 0);
 
 /* ------------------------------------------------------------- */