1 files changed, 16 insertions, 12 deletions

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index b53b53bb1475..429994d5bc8b 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -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)