diff --git a/drivers/isdn/i4l/isdn_net.c b/drivers/isdn/i4l/isdn_net.c
index 8209ed6..57bf4bf 100644
--- a/drivers/isdn/i4l/isdn_net.c
+++ b/drivers/isdn/i4l/isdn_net.c
@@ -1051,12 +1051,12 @@
 	isdn_net_dev *nd;
 	isdn_net_local *slp;
 	isdn_net_local *lp = (isdn_net_local *) netdev_priv(ndev);
-	int retv = 0;
+	int retv = NETDEV_TX_OK;
 
 	if (((isdn_net_local *) netdev_priv(ndev))->master) {
 		printk("isdn BUG at %s:%d!\n", __FILE__, __LINE__);
 		dev_kfree_skb(skb);
-		return 0;
+		return NETDEV_TX_OK;
 	}
 
 	/* For the other encaps the header has already been built */
diff --git a/drivers/isdn/i4l/isdn_ppp.c b/drivers/isdn/i4l/isdn_ppp.c
index aa30b5c..2d14b64 100644
--- a/drivers/isdn/i4l/isdn_ppp.c
+++ b/drivers/isdn/i4l/isdn_ppp.c
@@ -1223,7 +1223,7 @@
 	isdn_net_dev *nd;
 	unsigned int proto = PPP_IP;     /* 0x21 */
 	struct ippp_struct *ipt,*ipts;
-	int slot, retval = 0;
+	int slot, retval = NETDEV_TX_OK;
 
 	mlp = (isdn_net_local *) netdev_priv(netdev);
 	nd = mlp->netdev;       /* get master lp */
@@ -1240,7 +1240,7 @@
 	if (!(ipts->pppcfg & SC_ENABLE_IP)) {	/* PPP connected ? */
 		if (ipts->debug & 0x1)
 			printk(KERN_INFO "%s: IP frame delayed.\n", netdev->name);
-		retval = 1;
+		retval = NETDEV_TX_BUSY;
 		goto out;
 	}
 
@@ -1261,7 +1261,7 @@
 	lp = isdn_net_get_locked_lp(nd);
 	if (!lp) {
 		printk(KERN_WARNING "%s: all channels busy - requeuing!\n", netdev->name);
-		retval = 1;
+		retval = NETDEV_TX_BUSY;
 		goto out;
 	}
 	/* we have our lp locked from now on */