1 files changed, 17 insertions, 16 deletions

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 34e75bc8f4c..9224fc3184e 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -105,7 +105,7 @@ static struct old_serial_port old_serial_port[] = {
 	SERIAL_PORT_DFNS /* defined in asm/serial.h */
 };
 
-#define UART_NR	(ARRAY_SIZE(old_serial_port) + CONFIG_SERIAL_8250_NR_UARTS)
+#define UART_NR	CONFIG_SERIAL_8250_NR_UARTS
 
 #ifdef CONFIG_SERIAL_8250_RSA
 
@@ -993,21 +993,24 @@ static void autoconfig_irq(struct uart_8250_port *up)
 	up->port.irq = (irq > 0) ? irq : 0;
 }
 
+static inline void __stop_tx(struct uart_8250_port *p)
+{
+	if (p->ier & UART_IER_THRI) {
+		p->ier &= ~UART_IER_THRI;
+		serial_out(p, UART_IER, p->ier);
+	}
+}
+
 static void serial8250_stop_tx(struct uart_port *port, unsigned int tty_stop)
 {
 	struct uart_8250_port *up = (struct uart_8250_port *)port;
 
-	if (up->ier & UART_IER_THRI) {
-		up->ier &= ~UART_IER_THRI;
-		serial_out(up, UART_IER, up->ier);
-	}
+	__stop_tx(up);
 
 	/*
-	 * We only do this from uart_stop - if we run out of
-	 * characters to send, we don't want to prevent the
-	 * FIFO from emptying.
+	 * We really want to stop the transmitter from sending.
 	 */
-	if (up->port.type == PORT_16C950 && tty_stop) {
+	if (up->port.type == PORT_16C950) {
 		up->acr |= UART_ACR_TXDIS;
 		serial_icr_write(up, UART_ACR, up->acr);
 	}
@@ -1031,10 +1034,11 @@ static void serial8250_start_tx(struct uart_port *port, unsigned int tty_start)
 				transmit_chars(up);
 		}
 	}
+
 	/*
-	 * We only do this from uart_start
+	 * Re-enable the transmitter if we disabled it.
 	 */
-	if (tty_start && up->port.type == PORT_16C950) {
+	if (up->port.type == PORT_16C950 && up->acr & UART_ACR_TXDIS) {
 		up->acr &= ~UART_ACR_TXDIS;
 		serial_icr_write(up, UART_ACR, up->acr);
 	}
@@ -1155,7 +1159,7 @@ static _INLINE_ void transmit_chars(struct uart_8250_port *up)
 		return;
 	}
 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
-		serial8250_stop_tx(&up->port, 0);
+		__stop_tx(up);
 		return;
 	}
 
@@ -1174,7 +1178,7 @@ static _INLINE_ void transmit_chars(struct uart_8250_port *up)
 	DEBUG_INTR("THRE...");
 
 	if (uart_circ_empty(xmit))
-		serial8250_stop_tx(&up->port, 0);
+		__stop_tx(up);
 }
 
 static _INLINE_ void check_modem_status(struct uart_8250_port *up)
@@ -1376,13 +1380,10 @@ static unsigned int serial8250_tx_empty(struct uart_port *port)
 static unsigned int serial8250_get_mctrl(struct uart_port *port)
 {
 	struct uart_8250_port *up = (struct uart_8250_port *)port;
-	unsigned long flags;
 	unsigned char status;
 	unsigned int ret;
 
-	spin_lock_irqsave(&up->port.lock, flags);
 	status = serial_in(up, UART_MSR);
-	spin_unlock_irqrestore(&up->port.lock, flags);
 
 	ret = 0;
 	if (status & UART_MSR_DCD)