diff --git a/drivers/tty/synclinkmp.c b/drivers/tty/synclinkmp.c
index 5454025..6d5780c 100644
--- a/drivers/tty/synclinkmp.c
+++ b/drivers/tty/synclinkmp.c
@@ -882,7 +882,7 @@
 	/* Handle transition to B0 status */
 	if (old_termios->c_cflag & CBAUD &&
 	    !(tty->termios.c_cflag & CBAUD)) {
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		spin_lock_irqsave(&info->lock,flags);
 	 	set_signals(info);
 		spin_unlock_irqrestore(&info->lock,flags);
@@ -1676,8 +1676,8 @@
 		return rc;
 	}
 
-	/* assert DTR and RTS, apply hardware settings */
-	info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+	/* assert RTS and DTR, apply hardware settings */
+	info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	program_hw(info);
 
 	/* enable network layer transmit */
@@ -2706,7 +2706,7 @@
 	reset_port(info);
 
  	if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- 		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		set_signals(info);
 	}
 
@@ -2768,12 +2768,12 @@
 
 	cflag = info->port.tty->termios.c_cflag;
 
-	/* if B0 rate (hangup) specified then negate DTR and RTS */
-	/* otherwise assert DTR and RTS */
+	/* if B0 rate (hangup) specified then negate RTS and DTR */
+	/* otherwise assert RTS and DTR */
  	if (cflag & CBAUD)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 
 	/* byte size and parity */
 
@@ -3212,12 +3212,12 @@
  	get_signals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
 
-	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
-		((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
-		((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
-		((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
-		((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
-		((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
+	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS : 0) |
+		 ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR : 0) |
+		 ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR : 0) |
+		 ((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG : 0) |
+		 ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR : 0) |
+		 ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS : 0);
 
 	if (debug_level >= DEBUG_LEVEL_INFO)
 		printk("%s(%d):%s tiocmget() value=%08X\n",
@@ -3272,9 +3272,9 @@
 
 	spin_lock_irqsave(&info->lock,flags);
 	if (on)
-		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
 	else
-		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
  	set_signals(info);
 	spin_unlock_irqrestore(&info->lock,flags);
 }
@@ -4354,7 +4354,7 @@
 		tx_stop(info);
 		rx_stop(info);
 
-		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
 		set_signals(info);
 
 		/* disable all port interrupts */
@@ -4750,8 +4750,8 @@
 	u16 gpstatus = read_status_reg(info);
 	u16 testbit;
 
-	/* clear all serial signals except DTR and RTS */
-	info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
+	/* clear all serial signals except RTS and DTR */
+	info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
 
 	/* set serial signal bits to reflect MISR */
 
@@ -4770,7 +4770,7 @@
 		info->serial_signals |= SerialSignal_DSR;
 }
 
-/* Set the state of DTR and RTS based on contents of
+/* Set the state of RTS and DTR based on contents of
  * serial_signals member of device context.
  */
 static void set_signals(SLMP_INFO *info)