diff --git a/drivers/isdn/hisax/hisax_fcpcipnp.c b/drivers/isdn/hisax/hisax_fcpcipnp.c
index e4f7573ba9bf..7a7137d8664b 100644
--- a/drivers/isdn/hisax/hisax_fcpcipnp.c
+++ b/drivers/isdn/hisax/hisax_fcpcipnp.c
@@ -940,6 +940,8 @@ static int fcpnp_probe(struct pnp_dev *pdev, const struct pnp_device_id *dev_id)
 	}
 	adapter->io = pnp_port_start(pdev, 0);
 	adapter->irq = pnp_irq(pdev, 0);
+	if (!adapter->io || adapter->irq == -1)
+		goto err_free;
 
 	printk(KERN_INFO "hisax_fcpcipnp: found adapter %s at IO %#x irq %d\n",
 	       (char *) dev_id->driver_data, adapter->io, adapter->irq);