TTY: add tty_port_tty_hangup helper

It allows for cleaning up on a considerable amount of places. They did
port_get, hangup, kref_put. Now the only thing needed is to call
tty_port_tty_hangup which does exactly that. And they can also decide
whether to consider CLOCAL or completely ignore that.

Signed-off-by: Jiri Slaby <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

arch/um/drivers/chan_kern.c

···
 		reactivate_fd(chan->fd, irq);
 	if (err == -EIO) {
 		if (chan->primary) {
-			struct tty_struct *tty = tty_port_tty_get(&line->port);
-			if (tty != NULL) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&line->port, false);
 			if (line->chan_out != chan)
 				close_one_chan(line->chan_out, 1);
 		}

drivers/mmc/card/sdio_uart.c

···
 static void sdio_uart_port_remove(struct sdio_uart_port *port)
 {
 	struct sdio_func *func;
-	struct tty_struct *tty;
 
 	BUG_ON(sdio_uart_table[port->index] != port);
 
···
 	sdio_claim_host(func);
 	port->func = NULL;
 	mutex_unlock(&port->func_lock);
-	tty = tty_port_tty_get(&port->port);
 	/* tty_hangup is async so is this safe as is ?? */
-	if (tty) {
-		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_tty_hangup(&port->port, false);
 	mutex_unlock(&port->port.mutex);
 	sdio_release_irq(func);
 	sdio_disable_func(func);
···
 			wake_up_interruptible(&port->port.open_wait);
 		else {
 			/* DCD drop - hang up if tty attached */
-			tty = tty_port_tty_get(&port->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&port->port, false);
 		}
 	}
 	if (status & UART_MSR_DCTS) {

drivers/net/usb/hso.c

···
 static void hso_free_interface(struct usb_interface *interface)
 {
 	struct hso_serial *hso_dev;
-	struct tty_struct *tty;
 	int i;
 
 	for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
 		if (serial_table[i] &&
 		    (serial_table[i]->interface == interface)) {
 			hso_dev = dev2ser(serial_table[i]);
-			tty = tty_port_tty_get(&hso_dev->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&hso_dev->port, false);
 			mutex_lock(&hso_dev->parent->mutex);
 			hso_dev->parent->usb_gone = 1;
 			mutex_unlock(&hso_dev->parent->mutex);

drivers/tty/cyclades.c

···
 					readl(&info->u.cyz.ch_ctrl->rs_status);
 				if (dcd & C_RS_DCD)
 					wake_up_interruptible(&info->port.open_wait);
-				else {
-					struct tty_struct *tty;
-					tty = tty_port_tty_get(&info->port);
-					if (tty) {
-						tty_hangup(tty);
-						tty_kref_put(tty);
-					}
-				}
+				else
+					tty_port_tty_hangup(&info->port, false);
 			}
 			break;
 		case C_CM_MCTS:

drivers/tty/moxa.c

···
 
 	/* pci hot-un-plug support */
 	for (a = 0; a < brd->numPorts; a++)
-		if (brd->ports[a].port.flags & ASYNC_INITIALIZED) {
-			struct tty_struct *tty = tty_port_tty_get(
-						&brd->ports[a].port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
-		}
+		if (brd->ports[a].port.flags & ASYNC_INITIALIZED)
+			tty_port_tty_hangup(&brd->ports[a].port, false);
+
 	for (a = 0; a < MAX_PORTS_PER_BOARD; a++)
 		tty_port_destroy(&brd->ports[a].port);
+
 	while (1) {
 		opened = 0;
 		for (a = 0; a < brd->numPorts; a++)
···
 
 static void moxa_new_dcdstate(struct moxa_port *p, u8 dcd)
 {
-	struct tty_struct *tty;
 	unsigned long flags;
 	dcd = !!dcd;
 
···
 	if (dcd != p->DCDState) {
         	p->DCDState = dcd;
         	spin_unlock_irqrestore(&p->port.lock, flags);
-		tty = tty_port_tty_get(&p->port);
-		if (tty && !C_CLOCAL(tty) && !dcd)
-			tty_hangup(tty);
-		tty_kref_put(tty);
+		if (!dcd)
+			tty_port_tty_hangup(&p->port, true);
 	}
 	else
 		spin_unlock_irqrestore(&p->port.lock, flags);

drivers/tty/n_gsm.c

···
 		pr_debug("DLCI %d goes closed.\n", dlci->addr);
 	dlci->state = DLCI_CLOSED;
 	if (dlci->addr != 0) {
-		struct tty_struct  *tty = tty_port_tty_get(&dlci->port);
-		if (tty) {
-			tty_hangup(tty);
-			tty_kref_put(tty);
-		}
+		tty_port_tty_hangup(&dlci->port, false);
 		kfifo_reset(dlci->fifo);
 	} else
 		dlci->gsm->dead = 1;

drivers/tty/nozomi.c

···
 
 	DBG1(" ");
 
-	for (i = 0; i < MAX_PORT; ++i) {
-		struct tty_struct *tty = tty_port_tty_get(&dc->port[i].port);
-		if (tty && list_empty(&tty->hangup_work.entry))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	for (i = 0; i < MAX_PORT; ++i)
+		tty_port_tty_hangup(&dc->port[i].port, false);
+
 	/* Racy below - surely should wait for scheduled work to be done or
 	   complete off a hangup method ? */
 	while (dc->open_ttys)

drivers/tty/rocket.c

···
 		       (ChanStatus & CD_ACT) ? "on" : "off");
 #endif
 		if (!(ChanStatus & CD_ACT) && info->cd_status) {
-			struct tty_struct *tty;
 #ifdef ROCKET_DEBUG_HANGUP
 			printk(KERN_INFO "CD drop, calling hangup.\n");
 #endif
-			tty = tty_port_tty_get(&info->port);
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&info->port, false);
 		}
 		info->cd_status = (ChanStatus & CD_ACT) ? 1 : 0;
 		wake_up_interruptible(&info->port.open_wait);

drivers/tty/serial/ifx6x60.c

···
 }
 
 /**
- *	ifx_spi_hangup		-	hang up an IFX device
- *	@ifx_dev: our SPI device
- *
- *	Hang up the tty attached to the IFX device if one is currently
- *	open. If not take no action
- */
-static void ifx_spi_ttyhangup(struct ifx_spi_device *ifx_dev)
-{
-	struct tty_port *pport = &ifx_dev->tty_port;
-	struct tty_struct *tty = tty_port_tty_get(pport);
-	if (tty) {
-		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
-}
-
-/**
  *	ifx_spi_timeout		-	SPI timeout
  *	@arg: our SPI device
  *
···
 	struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
 
 	dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
-	ifx_spi_ttyhangup(ifx_dev);
+	tty_port_tty_hangup(&ifx_dev->tty_port, false);
 	mrdy_set_low(ifx_dev);
 	clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);
 }
···
 		set_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
 		if (!solreset) {
 			/* unsolicited reset  */
-			ifx_spi_ttyhangup(ifx_dev);
+			tty_port_tty_hangup(&ifx_dev->tty_port, false);
 		}
 	} else {
 		/* exited reset */

drivers/tty/tty_port.c

···
 EXPORT_SYMBOL(tty_port_hangup);
 
 /**
+ * tty_port_tty_hangup - helper to hang up a tty
+ *
+ * @port: tty port
+ * @check_clocal: hang only ttys with CLOCAL unset?
+ */
+void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
+{
+	struct tty_struct *tty = tty_port_tty_get(port);
+
+	if (tty && (!check_clocal || !C_CLOCAL(tty))) {
+		tty_hangup(tty);
+		tty_kref_put(tty);
+	}
+}
+EXPORT_SYMBOL_GPL(tty_port_tty_hangup);
+
+/**
  * tty_port_tty_wakeup - helper to wake up a tty
  *
  * @port: tty port

drivers/usb/class/cdc-acm.c

···
 {
 	struct acm *acm = urb->context;
 	struct usb_cdc_notification *dr = urb->transfer_buffer;
-	struct tty_struct *tty;
 	unsigned char *data;
 	int newctrl;
 	int retval;
···
 		break;
 
 	case USB_CDC_NOTIFY_SERIAL_STATE:
-		tty = tty_port_tty_get(&acm->port);
 		newctrl = get_unaligned_le16(data);
 
-		if (tty) {
-			if (!acm->clocal &&
-				(acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
-				dev_dbg(&acm->control->dev,
-					"%s - calling hangup\n", __func__);
-				tty_hangup(tty);
-			}
-			tty_kref_put(tty);
+		if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
+			dev_dbg(&acm->control->dev, "%s - calling hangup\n",
+					__func__);
+			tty_port_tty_hangup(&acm->port, false);
 		}
 
 		acm->ctrlin = newctrl;
···
 static int acm_reset_resume(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
-	struct tty_struct *tty;
 
-	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
-		tty = tty_port_tty_get(&acm->port);
-		if (tty) {
-			tty_hangup(tty);
-			tty_kref_put(tty);
-		}
-	}
+	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
+		tty_port_tty_hangup(&acm->port, false);
 
 	return acm_resume(intf);
 }

drivers/usb/serial/keyspan.c

···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state, err;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 		/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		struct tty_struct *tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	struct usb_serial			*serial;
 	struct usb_serial_port			*port;
 	struct keyspan_port_private	 	*p_priv;
-	struct tty_struct			*tty;
 	int old_dcd_state, err;
 	int status = urb->status;
 
···
 	p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
 	p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);
···
 	p_priv->cts_state = ((msg->hskia_cts) ? 1 : 0);
 	p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
 
-	if (old_dcd_state != p_priv->dcd_state && old_dcd_state) {
-		struct tty_struct *tty = tty_port_tty_get(&port->port);
-		if (tty && !C_CLOCAL(tty))
-			tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	if (old_dcd_state != p_priv->dcd_state && old_dcd_state)
+		tty_port_tty_hangup(&port->port, true);
 
 	/* Resubmit urb so we continue receiving */
 	err = usb_submit_urb(urb, GFP_ATOMIC);

drivers/usb/serial/option.c

···
 			portdata->dsr_state = ((signals & 0x02) ? 1 : 0);
 			portdata->ri_state = ((signals & 0x08) ? 1 : 0);
 
-			if (old_dcd_state && !portdata->dcd_state) {
-				struct tty_struct *tty =
-						tty_port_tty_get(&port->port);
-				if (tty && !C_CLOCAL(tty))
-					tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			if (old_dcd_state && !portdata->dcd_state)
+				tty_port_tty_hangup(&port->port, true);
 		} else {
 			dev_dbg(dev, "%s: type %x req %x\n", __func__,
 				req_pkt->bRequestType, req_pkt->bRequest);

drivers/usb/serial/sierra.c

···
 			unsigned char signals = *((unsigned char *)
 					urb->transfer_buffer +
 					sizeof(struct usb_ctrlrequest));
-			struct tty_struct *tty;
 
 			dev_dbg(&port->dev, "%s: signal x%x\n", __func__,
 				signals);
···
 			portdata->dsr_state = ((signals & 0x02) ? 1 : 0);
 			portdata->ri_state = ((signals & 0x08) ? 1 : 0);
 
-			tty = tty_port_tty_get(&port->port);
-			if (tty && !C_CLOCAL(tty) &&
-					old_dcd_state && !portdata->dcd_state)
-				tty_hangup(tty);
-			tty_kref_put(tty);
+			if (old_dcd_state && !portdata->dcd_state)
+				tty_port_tty_hangup(&port->port, true);
 		} else {
 			dev_dbg(&port->dev, "%s: type %x req %x\n",
 				__func__, req_pkt->bRequestType,

include/linux/tty.h

···
 extern void tty_port_raise_dtr_rts(struct tty_port *port);
 extern void tty_port_lower_dtr_rts(struct tty_port *port);
 extern void tty_port_hangup(struct tty_port *port);
+extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
 extern void tty_port_tty_wakeup(struct tty_port *port);
 extern int tty_port_block_til_ready(struct tty_port *port,
 				struct tty_struct *tty, struct file *filp);

net/irda/ircomm/ircomm_tty_attach.c

···
 			self->settings.dce = IRCOMM_DELTA_CD;
 			ircomm_tty_check_modem_status(self);
 		} else {
-			struct tty_struct *tty = tty_port_tty_get(&self->port);
 			IRDA_DEBUG(0, "%s(), hanging up!\n", __func__ );
-			if (tty) {
-				tty_hangup(tty);
-				tty_kref_put(tty);
-			}
+			tty_port_tty_hangup(&self->port, false);
 		}
 		break;
 	default: