diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 9075bbb56ad4322d123d42a8f5e77e68e7a964f2..f766bc22c6bbe5e9e4e46a0eee51826fe89b9131 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -576,7 +576,7 @@ static void __exit hci_uart_exit(void)
 #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 b3dbff1cf967b504fd8048d110c1dd2927692038..5079beda69b5af142af8e9bfaa4ffd62c635c881 100644
--- a/drivers/char/n_hdlc.c
+++ b/drivers/char/n_hdlc.c
@@ -960,7 +960,7 @@ static char hdlc_unregister_fail[] __exitdata =
 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 3883073ab48f556e4d080b6721a2b194bdce9250..2291a87e8ada6ce17070bfc38ceb41f512290568 100644
--- a/drivers/char/n_r3964.c
+++ b/drivers/char/n_r3964.c
@@ -200,7 +200,7 @@ static void __exit r3964_exit(void)
    
    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 f6b85222ba3dc9033fff294d6f45e7cc2f6986e3..79ca38469159b90abd6d1f52bffb162dbb89968c 100644
--- a/drivers/input/serio/serport.c
+++ b/drivers/input/serio/serport.c
@@ -257,7 +257,7 @@ static int __init serport_init(void)
 
 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 89454915b857dcf72b6b64be822108adc14eb377..e44f8e9055ef0c6e82a1d908ae70ecbfa3f678d3 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -848,7 +848,7 @@ static void __exit sixpack_exit_driver(void)
 {
 	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 62790511098f6506241b94fa9f8043c0c02047aa..3035422f5ad8c867dfdfaeb151f7e05647c572ca 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/drivers/net/hamradio/mkiss.c
@@ -934,7 +934,7 @@ static void __exit mkiss_exit_driver(void)
 	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 7d23aa3759089aca9a15765e7556d8599b7204f5..b8d112348ba40a01f00811402a8d7a525931b313 100644
--- a/drivers/net/irda/irtty-sir.c
+++ b/drivers/net/irda/irtty-sir.c
@@ -626,7 +626,7 @@ static void __exit irtty_sir_cleanup(void)
 {
 	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 33b9d79b1aadad177ee5b4dab213199bb8de63ff..5e48b9ab30455ca661f3c03c6bb128910778d22c 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -1025,7 +1025,7 @@ static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
 
 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 7d0150b4c629c089ae0f39e57ae4eb91eb475592..fd9f50180355b79bef8ae07a7fe44b68621a59f5 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -793,7 +793,7 @@ ppp_sync_input(struct syncppp *ap, const unsigned char *buf,
 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 8f7841c0374d38d7caaaf7b6003882c83cc1582b..19112712daf03ccab4eee49fa32063dbba5e0e84 100644
--- a/drivers/net/slip.c
+++ b/drivers/net/slip.c
@@ -1430,7 +1430,7 @@ static void __exit slip_exit(void)
 	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 1c540d825551f6c0194d30e19a5cb51ffcaec5b4..bdf672c48182a148dd5420f4aee505f340d2114e 100644
--- a/drivers/net/wan/x25_asy.c
+++ b/drivers/net/wan/x25_asy.c
@@ -829,7 +829,7 @@ static void __exit exit_x25_asy(void)
 	}
 
 	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 ec8cf29ffcedc838389cb987a9e87134fa0f11fc..6c42b573a95a9138fb407df50eb5ef12ad797b57 100644
--- a/drivers/net/wireless/strip.c
+++ b/drivers/net/wireless/strip.c
@@ -2828,7 +2828,7 @@ static void __exit strip_exit_driver(void)
 	/* 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);