3 files changed, 22 insertions, 12 deletions

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 954941dd8..f9c798cba 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -482,19 +482,21 @@ static void atmel_start_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (atmel_use_pdc_tx(port)) {
-		if (atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN)
-			/* The transmitter is already running.  Yes, we
-			   really need this.*/
-			return;
+	if (atmel_use_pdc_tx(port) && (atmel_uart_readl(port, ATMEL_PDC_PTSR)
+				       & ATMEL_PDC_TXTEN))
+		/* The transmitter is already running.  Yes, we
+		   really need this.*/
+		return;
 
+	if (atmel_use_pdc_tx(port) || atmel_use_dma_tx(port))
 		if ((port->rs485.flags & SER_RS485_ENABLED) &&
 		    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
 			atmel_stop_rx(port);
 
+	if (atmel_use_pdc_tx(port))
 		/* re-enable PDC transmit */
 		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
-	}
+
 	/* Enable interrupts */
 	atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask);
 }
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index b7d80bd57..7d62610d9 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -726,7 +726,7 @@ static void msm_handle_tx(struct uart_port *port)
 		return;
 	}
 
-	pio_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 	dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 
 	dma_min = 1;	/* Always DMA */
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 99bb23161..f0bd2ec0d 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1684,7 +1684,7 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
 		return -ENODEV;
 
 	if (port->mapbase != 0)
-		return 0;
+		return -EINVAL;
 
 	/* setup info for port */
 	port->dev	= &platdev->dev;
@@ -1738,22 +1738,25 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
 		ourport->dma = devm_kzalloc(port->dev,
 					    sizeof(*ourport->dma),
 					    GFP_KERNEL);
-		if (!ourport->dma)
-			return -ENOMEM;
+		if (!ourport->dma) {
+			ret = -ENOMEM;
+			goto err;
+		}
 	}
 
 	ourport->clk	= clk_get(&platdev->dev, "uart");
 	if (IS_ERR(ourport->clk)) {
 		pr_err("%s: Controller clock not found\n",
 				dev_name(&platdev->dev));
-		return PTR_ERR(ourport->clk);
+		ret = PTR_ERR(ourport->clk);
+		goto err;
 	}
 
 	ret = clk_prepare_enable(ourport->clk);
 	if (ret) {
 		pr_err("uart: clock failed to prepare+enable: %d\n", ret);
 		clk_put(ourport->clk);
-		return ret;
+		goto err;
 	}
 
 	/* Keep all interrupts masked and cleared */
@@ -1769,7 +1772,12 @@ static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
 
 	/* reset the fifos (and setup the uart) */
 	s3c24xx_serial_resetport(port, cfg);
+
 	return 0;
+
+err:
+	port->mapbase = 0;
+	return ret;
 }
 
 /* Device driver serial port probe */