1 files changed, 32 insertions, 48 deletions

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index bd07f79a2df9..f1c06e12efa0 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -552,19 +552,23 @@ static u_int atmel_get_mctrl(struct uart_port *port)
 static void atmel_stop_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	bool is_pdc = atmel_use_pdc_tx(port);
+	bool is_dma = is_pdc || atmel_use_dma_tx(port);
 
-	if (atmel_use_pdc_tx(port)) {
+	if (is_pdc) {
 		/* disable PDC transmit */
 		atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
 	}
 
-	/*
-	 * Disable the transmitter.
-	 * This is mandatory when DMA is used, otherwise the DMA buffer
-	 * is fully transmitted.
-	 */
-	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS);
-	atmel_port->tx_stopped = true;
+	if (is_dma) {
+		/*
+		 * Disable the transmitter.
+		 * This is mandatory when DMA is used, otherwise the DMA buffer
+		 * is fully transmitted.
+		 */
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS);
+		atmel_port->tx_stopped = true;
+	}
 
 	/* Disable interrupts */
 	atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask);
@@ -572,7 +576,6 @@ static void atmel_stop_tx(struct uart_port *port)
 	if (atmel_uart_is_half_duplex(port))
 		if (!atomic_read(&atmel_port->tasklet_shutdown))
 			atmel_start_rx(port);
-
 }
 
 /*
@@ -581,27 +584,31 @@ static void atmel_stop_tx(struct uart_port *port)
 static void atmel_start_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	bool is_pdc = atmel_use_pdc_tx(port);
+	bool is_dma = is_pdc || atmel_use_dma_tx(port);
 
-	if (atmel_use_pdc_tx(port) && (atmel_uart_readl(port, ATMEL_PDC_PTSR)
+	if (is_pdc && (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 (atmel_uart_is_half_duplex(port))
-			atmel_stop_rx(port);
+	if (is_dma && atmel_uart_is_half_duplex(port))
+		atmel_stop_rx(port);
 
-	if (atmel_use_pdc_tx(port))
+	if (is_pdc) {
 		/* 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);
 
-	/* re-enable the transmitter */
-	atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN);
-	atmel_port->tx_stopped = false;
+	if (is_dma) {
+		/* re-enable the transmitter */
+		atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN);
+		atmel_port->tx_stopped = false;
+	}
 }
 
 /*
@@ -824,30 +831,14 @@ static void atmel_rx_chars(struct uart_port *port)
  */
 static void atmel_tx_chars(struct uart_port *port)
 {
-	struct circ_buf *xmit = &port->state->xmit;
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	bool pending;
+	u8 ch;
 
-	if (port->x_char &&
-	    (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY)) {
-		atmel_uart_write_char(port, port->x_char);
-		port->icount.tx++;
-		port->x_char = 0;
-	}
-	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
-		return;
-
-	while (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY) {
-		atmel_uart_write_char(port, xmit->buf[xmit->tail]);
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-		if (uart_circ_empty(xmit))
-			break;
-	}
-
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(port);
-
-	if (!uart_circ_empty(xmit)) {
+	pending = uart_port_tx(port, ch,
+		atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY,
+		atmel_uart_write_char(port, ch));
+	if (pending) {
 		/* we still have characters to transmit, so we should continue
 		 * transmitting them when TX is ready, regardless of
 		 * mode or duplexity
@@ -875,10 +866,7 @@ static void atmel_complete_tx_dma(void *arg)
 
 	if (chan)
 		dmaengine_terminate_all(chan);
-	xmit->tail += atmel_port->tx_len;
-	xmit->tail &= UART_XMIT_SIZE - 1;
-
-	port->icount.tx += atmel_port->tx_len;
+	uart_xmit_advance(port, atmel_port->tx_len);
 
 	spin_lock_irq(&atmel_port->lock_tx);
 	async_tx_ack(atmel_port->desc_tx);
@@ -1471,11 +1459,7 @@ static void atmel_tx_pdc(struct uart_port *port)
 	/* nothing left to transmit? */
 	if (atmel_uart_readl(port, ATMEL_PDC_TCR))
 		return;
-
-	xmit->tail += pdc->ofs;
-	xmit->tail &= UART_XMIT_SIZE - 1;
-
-	port->icount.tx += pdc->ofs;
+	uart_xmit_advance(port, pdc->ofs);
 	pdc->ofs = 0;
 
 	/* more to transmit - setup next transfer */