diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 9075bbb..f766bc2 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -576,7 +576,7 @@
 #endif
 
 	/* Release tty registration of line discipline */
-	if ((err = tty_register_ldisc(N_HCI, NULL)))
+	if ((err = tty_unregister_ldisc(N_HCI)))
 		BT_ERR("Can't unregister HCI line discipline (%d)", err);
 }
 
diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c
index b3dbff1..5079beda 100644
--- a/drivers/char/n_hdlc.c
+++ b/drivers/char/n_hdlc.c
@@ -960,7 +960,7 @@
 static void __exit n_hdlc_exit(void)
 {
 	/* Release tty registration of line discipline */
-	int status = tty_register_ldisc(N_HDLC, NULL);
+	int status = tty_unregister_ldisc(N_HDLC);
 
 	if (status)
 		printk(hdlc_unregister_fail, status);
diff --git a/drivers/char/n_r3964.c b/drivers/char/n_r3964.c
index 3883073..2291a87 100644
--- a/drivers/char/n_r3964.c
+++ b/drivers/char/n_r3964.c
@@ -200,7 +200,7 @@
    
    TRACE_M ("cleanup_module()");
 
-   status=tty_register_ldisc(N_R3964, NULL);
+   status=tty_unregister_ldisc(N_R3964);
    
    if(status!=0)
    {
diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c
index f6b8522..79ca384 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -257,7 +257,7 @@
 
 static void __exit serport_exit(void)
 {
-	tty_register_ldisc(N_MOUSE, NULL);
+	tty_unregister_ldisc(N_MOUSE);
 }
 
 module_init(serport_init);
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 8945491..e44f8e9 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -848,7 +848,7 @@
 {
 	int ret;
 
-	if ((ret = tty_register_ldisc(N_6PACK, NULL)))
+	if ((ret = tty_unregister_ldisc(N_6PACK)))
 		printk(msg_unregfail, ret);
 }
 
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c
index 6279051..3035422 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/drivers/net/hamradio/mkiss.c
@@ -934,7 +934,7 @@
 	kfree(ax25_ctrls);
 	ax25_ctrls = NULL;
 
-	if ((i = tty_register_ldisc(N_AX25, NULL)))
+	if ((i = tty_unregister_ldisc(N_AX25)))
 		printk(KERN_ERR "mkiss: can't unregister line discipline (err = %d)\n", i);
 }
 
diff --git a/drivers/net/irda/irtty-sir.c b/drivers/net/irda/irtty-sir.c
index 7d23aa3..b8d1123 100644
--- a/drivers/net/irda/irtty-sir.c
+++ b/drivers/net/irda/irtty-sir.c
@@ -626,7 +626,7 @@
 {
 	int err;
 
-	if ((err = tty_register_ldisc(N_IRDA, NULL))) {
+	if ((err = tty_unregister_ldisc(N_IRDA))) {
 		IRDA_ERROR("%s(), can't unregister line discipline (err = %d)\n",
 			   __FUNCTION__, err);
 	}
diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index 33b9d79..5e48b9a 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -1025,7 +1025,7 @@
 
 static void __exit ppp_async_cleanup(void)
 {
-	if (tty_register_ldisc(N_PPP, NULL) != 0)
+	if (tty_unregister_ldisc(N_PPP) != 0)
 		printk(KERN_ERR "failed to unregister PPP line discipline\n");
 }
 
diff --git a/drivers/net/ppp_synctty.c b/drivers/net/ppp_synctty.c
index 7d0150b..fd9f501 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -793,7 +793,7 @@
 static void __exit
 ppp_sync_cleanup(void)
 {
-	if (tty_register_ldisc(N_SYNC_PPP, NULL) != 0)
+	if (tty_unregister_ldisc(N_SYNC_PPP) != 0)
 		printk(KERN_ERR "failed to unregister Sync PPP line discipline\n");
 }
 
diff --git a/drivers/net/slip.c b/drivers/net/slip.c
index 8f7841c..1911271 100644
--- a/drivers/net/slip.c
+++ b/drivers/net/slip.c
@@ -1430,7 +1430,7 @@
 	kfree(slip_devs);
 	slip_devs = NULL;
 
-	if ((i = tty_register_ldisc(N_SLIP, NULL)))
+	if ((i = tty_unregister_ldisc(N_SLIP)))
 	{
 		printk(KERN_ERR "SLIP: can't unregister line discipline (err = %d)\n", i);
 	}
diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c
index 1c540d8..bdf672c 100644
--- a/drivers/net/wan/x25_asy.c
+++ b/drivers/net/wan/x25_asy.c
@@ -829,7 +829,7 @@
 	}
 
 	kfree(x25_asy_devs);
-	tty_register_ldisc(N_X25, NULL);
+	tty_unregister_ldisc(N_X25);
 }
 
 module_init(init_x25_asy);
diff --git a/drivers/net/wireless/strip.c b/drivers/net/wireless/strip.c
index ec8cf29f..6c42b57 100644
--- a/drivers/net/wireless/strip.c
+++ b/drivers/net/wireless/strip.c
@@ -2828,7 +2828,7 @@
 	/* Unregister with the /proc/net file here. */
 	proc_net_remove("strip");
 
-	if ((i = tty_register_ldisc(N_STRIP, NULL)))
+	if ((i = tty_unregister_ldisc(N_STRIP)))
 		printk(KERN_ERR "STRIP: can't unregister line discipline (err = %d)\n", i);
 
 	printk(signoff);