diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
index baa46e8a094b..4391138e1b8a 100644
--- a/drivers/char/pcmcia/synclink_cs.c
+++ b/drivers/char/pcmcia/synclink_cs.c
@@ -377,7 +377,7 @@ static void async_mode(MGSLPC_INFO *info);
 
 static void tx_timeout(struct timer_list *t);
 
-static int carrier_raised(struct tty_port *port);
+static bool carrier_raised(struct tty_port *port);
 static void dtr_rts(struct tty_port *port, int onoff);
 
 #if SYNCLINK_GENERIC_HDLC
@@ -2430,7 +2430,7 @@ static void mgslpc_hangup(struct tty_struct *tty)
 	tty_port_hangup(&info->port);
 }
 
-static int carrier_raised(struct tty_port *port)
+static bool carrier_raised(struct tty_port *port)
 {
 	MGSLPC_INFO *info = container_of(port, MGSLPC_INFO, port);
 	unsigned long flags;
@@ -2439,9 +2439,7 @@ static int carrier_raised(struct tty_port *port)
 	get_signals(info);
 	spin_unlock_irqrestore(&info->lock, flags);
 
-	if (info->serial_signals & SerialSignal_DCD)
-		return 1;
-	return 0;
+	return info->serial_signals & SerialSignal_DCD;
 }
 
 static void dtr_rts(struct tty_port *port, int onoff)
diff --git a/drivers/mmc/core/sdio_uart.c b/drivers/mmc/core/sdio_uart.c
index ae7ef2e038be..47f58258d8ff 100644
--- a/drivers/mmc/core/sdio_uart.c
+++ b/drivers/mmc/core/sdio_uart.c
@@ -526,7 +526,7 @@ static void sdio_uart_irq(struct sdio_func *func)
 	port->in_sdio_uart_irq = NULL;
 }
 
-static int uart_carrier_raised(struct tty_port *tport)
+static bool uart_carrier_raised(struct tty_port *tport)
 {
 	struct sdio_uart_port *port =
 			container_of(tport, struct sdio_uart_port, port);
@@ -535,9 +535,8 @@ static int uart_carrier_raised(struct tty_port *tport)
 		return 1;
 	ret = sdio_uart_get_mctrl(port);
 	sdio_uart_release_func(port);
-	if (ret & TIOCM_CAR)
-		return 1;
-	return 0;
+
+	return ret & TIOCM_CAR;
 }
 
 /**
diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 460d33a1e70b..01c4fd3ce7c8 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -1454,7 +1454,7 @@ static const struct tty_operations serial_ops = {
 	.proc_show = rs_proc_show,
 };
 
-static int amiga_carrier_raised(struct tty_port *port)
+static bool amiga_carrier_raised(struct tty_port *port)
 {
 	return !(ciab.pra & SER_DCD);
 }
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c
index 2d9635e14ded..6a1e78e33a2c 100644
--- a/drivers/tty/moxa.c
+++ b/drivers/tty/moxa.c
@@ -501,7 +501,7 @@ static int moxa_tiocmset(struct tty_struct *tty,
 static void moxa_poll(struct timer_list *);
 static void moxa_set_tty_param(struct tty_struct *, const struct ktermios *);
 static void moxa_shutdown(struct tty_port *);
-static int moxa_carrier_raised(struct tty_port *);
+static bool moxa_carrier_raised(struct tty_port *);
 static void moxa_dtr_rts(struct tty_port *, int);
 /*
  * moxa board interface functions:
@@ -1432,7 +1432,7 @@ static void moxa_shutdown(struct tty_port *port)
 	MoxaPortFlushData(ch, 2);
 }
 
-static int moxa_carrier_raised(struct tty_port *port)
+static bool moxa_carrier_raised(struct tty_port *port)
 {
 	struct moxa_port *ch = container_of(port, struct moxa_port, port);
 	int dcd;
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 2926a831727d..96c72e691cd7 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -458,10 +458,11 @@ static void __mxser_stop_tx(struct mxser_port *info)
 	outb(info->IER, info->ioaddr + UART_IER);
 }
 
-static int mxser_carrier_raised(struct tty_port *port)
+static bool mxser_carrier_raised(struct tty_port *port)
 {
 	struct mxser_port *mp = container_of(port, struct mxser_port, port);
-	return (inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD)?1:0;
+
+	return inb(mp->ioaddr + UART_MSR) & UART_MSR_DCD;
 }
 
 static void mxser_dtr_rts(struct tty_port *port, int on)
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 631539c17d85..81fc2ec3693f 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -3770,16 +3770,16 @@ static int gsm_modem_update(struct gsm_dlci *dlci, u8 brk)
 	return -EPROTONOSUPPORT;
 }
 
-static int gsm_carrier_raised(struct tty_port *port)
+static bool gsm_carrier_raised(struct tty_port *port)
 {
 	struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port);
 	struct gsm_mux *gsm = dlci->gsm;
 
 	/* Not yet open so no carrier info */
 	if (dlci->state != DLCI_OPEN)
-		return 0;
+		return false;
 	if (debug & DBG_CD_ON)
-		return 1;
+		return true;
 
 	/*
 	 * Basic mode with control channel in ADM mode may not respond
@@ -3787,7 +3787,7 @@ static int gsm_carrier_raised(struct tty_port *port)
 	 */
 	if (gsm->encoding == GSM_BASIC_OPT &&
 	    gsm->dlci[0]->mode == DLCI_MODE_ADM && !dlci->modem_rx)
-		return 1;
+		return true;
 
 	return dlci->modem_rx & TIOCM_CD;
 }
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index f7074ac02801..20ed8a088b2d 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -1861,7 +1861,7 @@ static void uart_port_shutdown(struct tty_port *port)
 	}
 }
 
-static int uart_carrier_raised(struct tty_port *port)
+static bool uart_carrier_raised(struct tty_port *port)
 {
 	struct uart_state *state = container_of(port, struct uart_state, port);
 	struct uart_port *uport;
@@ -1875,15 +1875,14 @@ static int uart_carrier_raised(struct tty_port *port)
 	 * continue and not sleep
 	 */
 	if (WARN_ON(!uport))
-		return 1;
+		return true;
 	spin_lock_irq(&uport->lock);
 	uart_enable_ms(uport);
 	mctrl = uport->ops->get_mctrl(uport);
 	spin_unlock_irq(&uport->lock);
 	uart_port_deref(uport);
-	if (mctrl & TIOCM_CAR)
-		return 1;
-	return 0;
+
+	return mctrl & TIOCM_CAR;
 }
 
 static void uart_dtr_rts(struct tty_port *port, int raise)
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index 81c94906f06e..4ba71ec764f7 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -3126,7 +3126,7 @@ static int tiocmset(struct tty_struct *tty,
 	return 0;
 }
 
-static int carrier_raised(struct tty_port *port)
+static bool carrier_raised(struct tty_port *port)
 {
 	unsigned long flags;
 	struct slgt_info *info = container_of(port, struct slgt_info, port);
@@ -3134,7 +3134,8 @@ static int carrier_raised(struct tty_port *port)
 	spin_lock_irqsave(&info->lock,flags);
 	get_gtsignals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
-	return (info->signals & SerialSignal_DCD) ? 1 : 0;
+
+	return info->signals & SerialSignal_DCD;
 }
 
 static void dtr_rts(struct tty_port *port, int on)
@@ -3162,7 +3163,7 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
 	int		retval;
 	bool		do_clocal = false;
 	unsigned long	flags;
-	int		cd;
+	bool		cd;
 	struct tty_port *port = &info->port;
 
 	DBGINFO(("%s block_til_ready\n", tty->driver->name));
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 469de3c010b8..a573c500f95b 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -444,10 +444,10 @@ EXPORT_SYMBOL_GPL(tty_port_tty_wakeup);
  * to hide some internal details. This will eventually become entirely
  * internal to the tty port.
  */
-int tty_port_carrier_raised(struct tty_port *port)
+bool tty_port_carrier_raised(struct tty_port *port)
 {
 	if (port->ops->carrier_raised == NULL)
-		return 1;
+		return true;
 	return port->ops->carrier_raised(port);
 }
 EXPORT_SYMBOL(tty_port_carrier_raised);
diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 6e1b87e67304..792f01a4ed22 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -413,12 +413,11 @@ static void ch341_port_remove(struct usb_serial_port *port)
 	kfree(priv);
 }
 
-static int ch341_carrier_raised(struct usb_serial_port *port)
+static bool ch341_carrier_raised(struct usb_serial_port *port)
 {
 	struct ch341_private *priv = usb_get_serial_port_data(port);
-	if (priv->msr & CH341_BIT_DCD)
-		return 1;
-	return 0;
+
+	return priv->msr & CH341_BIT_DCD;
 }
 
 static void ch341_dtr_rts(struct usb_serial_port *port, int on)
diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
index 891fb1fe69df..1a8c2925c26f 100644
--- a/drivers/usb/serial/f81232.c
+++ b/drivers/usb/serial/f81232.c
@@ -774,7 +774,7 @@ static bool f81232_tx_empty(struct usb_serial_port *port)
 	return true;
 }
 
-static int f81232_carrier_raised(struct usb_serial_port *port)
+static bool f81232_carrier_raised(struct usb_serial_port *port)
 {
 	u8 msr;
 	struct f81232_private *priv = usb_get_serial_port_data(port);
@@ -783,9 +783,7 @@ static int f81232_carrier_raised(struct usb_serial_port *port)
 	msr = priv->modem_status;
 	mutex_unlock(&priv->lock);
 
-	if (msr & UART_MSR_DCD)
-		return 1;
-	return 0;
+	return msr & UART_MSR_DCD;
 }
 
 static void f81232_get_serial(struct tty_struct *tty, struct serial_struct *ss)
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 8949c1891164..4cb81746a149 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -1050,14 +1050,11 @@ static int pl2303_tiocmget(struct tty_struct *tty)
 	return result;
 }
 
-static int pl2303_carrier_raised(struct usb_serial_port *port)
+static bool pl2303_carrier_raised(struct usb_serial_port *port)
 {
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 
-	if (priv->line_status & UART_DCD)
-		return 1;
-
-	return 0;
+	return priv->line_status & UART_DCD;
 }
 
 static void pl2303_set_break(struct usb_serial_port *port, bool enable)
diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c
index 09a972a838ee..8175db6c4554 100644
--- a/drivers/usb/serial/spcp8x5.c
+++ b/drivers/usb/serial/spcp8x5.c
@@ -247,16 +247,13 @@ static void spcp8x5_set_work_mode(struct usb_serial_port *port, u16 value,
 		dev_err(&port->dev, "failed to set work mode: %d\n", ret);
 }
 
-static int spcp8x5_carrier_raised(struct usb_serial_port *port)
+static bool spcp8x5_carrier_raised(struct usb_serial_port *port)
 {
 	u8 msr;
 	int ret;
 
 	ret = spcp8x5_get_msr(port, &msr);
-	if (ret || msr & MSR_STATUS_LINE_DCD)
-		return 1;
-
-	return 0;
+	return ret || msr & MSR_STATUS_LINE_DCD;
 }
 
 static void spcp8x5_dtr_rts(struct usb_serial_port *port, int on)
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 164521ee10c6..019720a63fac 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -754,7 +754,7 @@ static struct usb_serial_driver *search_serial_device(
 	return NULL;
 }
 
-static int serial_port_carrier_raised(struct tty_port *port)
+static bool serial_port_carrier_raised(struct tty_port *port)
 {
 	struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 	struct usb_serial_driver *drv = p->serial->type;
@@ -762,7 +762,7 @@ static int serial_port_carrier_raised(struct tty_port *port)
 	if (drv->carrier_raised)
 		return drv->carrier_raised(p);
 	/* No carrier control - don't block */
-	return 1;
+	return true;
 }
 
 static void serial_port_dtr_rts(struct tty_port *port, int on)
diff --git a/include/linux/tty_port.h b/include/linux/tty_port.h
index fa3c3bdaa234..cf098459cb01 100644
--- a/include/linux/tty_port.h
+++ b/include/linux/tty_port.h
@@ -15,7 +15,7 @@ struct tty_struct;
 
 /**
  * struct tty_port_operations -- operations on tty_port
- * @carrier_raised: return 1 if the carrier is raised on @port
+ * @carrier_raised: return true if the carrier is raised on @port
  * @dtr_rts: raise the DTR line if @raise is nonzero, otherwise lower DTR
  * @shutdown: called when the last close completes or a hangup finishes IFF the
  *	port was initialized. Do not use to free resources. Turn off the device
@@ -31,7 +31,7 @@ struct tty_struct;
  *	the port itself.
  */
 struct tty_port_operations {
-	int (*carrier_raised)(struct tty_port *port);
+	bool (*carrier_raised)(struct tty_port *port);
 	void (*dtr_rts)(struct tty_port *port, int raise);
 	void (*shutdown)(struct tty_port *port);
 	int (*activate)(struct tty_port *port, struct tty_struct *tty);
@@ -230,7 +230,7 @@ static inline void tty_port_set_kopened(struct tty_port *port, bool val)
 
 struct tty_struct *tty_port_tty_get(struct tty_port *port);
 void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
-int tty_port_carrier_raised(struct tty_port *port);
+bool tty_port_carrier_raised(struct tty_port *port);
 void tty_port_raise_dtr_rts(struct tty_port *port);
 void tty_port_lower_dtr_rts(struct tty_port *port);
 void tty_port_hangup(struct tty_port *port);
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index f7bfedb740f5..dc7f90522b42 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -293,7 +293,7 @@ struct usb_serial_driver {
 	/* Called by the tty layer for port level work. There may or may not
 	   be an attached tty at this point */
 	void (*dtr_rts)(struct usb_serial_port *port, int on);
-	int  (*carrier_raised)(struct usb_serial_port *port);
+	bool (*carrier_raised)(struct usb_serial_port *port);
 	/* Called by the usb serial hooks to allow the user to rework the
 	   termios state */
 	void (*init_termios)(struct tty_struct *tty);
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index 8009e0e93216..5697df9d4394 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -119,7 +119,7 @@ static int rfcomm_dev_activate(struct tty_port *port, struct tty_struct *tty)
 }
 
 /* we block the open until the dlc->state becomes BT_CONNECTED */
-static int rfcomm_dev_carrier_raised(struct tty_port *port)
+static bool rfcomm_dev_carrier_raised(struct tty_port *port)
 {
 	struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
 
