[PATCH 19/24] tty: serial: fsl_lpuart: Introduce lpuart_tx_dma_startup()

[Andrey Smirnov]

Code configure DMA TX path in lpuart_startup(), lpuart32_startup() and
lpuart_resume() is doing exactly the same thing, so move it into a
standalone subroutine.

Signed-off-by: Andrey Smirnov <andrew.smir...@gmail.com>
Cc: Stefan Agner <ste...@agner.ch>
Cc: Bhuvanchandra DV <bhuvanchandra...@toradex.com>
Cc: Chris Healy <cphe...@gmail.com>
Cc: Cory Tusar <cory.tu...@zii.aero>
Cc: Lucas Stach <l.st...@pengutronix.de>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Jiri Slaby <jsl...@suse.com>
Cc: linux-...@nxp.com
Cc: linux-ser...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/tty/serial/fsl_lpuart.c | 53 ++++++++++++++-------------------
 1 file changed, 23 insertions(+), 30 deletions(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 2ad5750fe511..558acf29cbed 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1434,6 +1434,26 @@ static void rx_dma_timer_init(struct lpuart_port *sport)
        add_timer(&sport->lpuart_timer);
 }
 
+static void lpuart_tx_dma_startup(struct lpuart_port *sport)
+{
+       u32 uartbaud;
+
+       if (sport->dma_tx_chan && !lpuart_dma_tx_request(&sport->port)) {
+               init_waitqueue_head(&sport->dma_wait);
+               sport->lpuart_dma_tx_use = true;
+               if (lpuart_is_32(sport)) {
+                       uartbaud = lpuart32_read(&sport->port, UARTBAUD);
+                       lpuart32_write(&sport->port,
+                                      uartbaud | UARTBAUD_TDMAE, UARTBAUD);
+               } else {
+                       writeb(readb(sport->port.membase + UARTCR5) |
+                               UARTCR5_TDMAS, sport->port.membase + UARTCR5);
+               }
+       } else {
+               sport->lpuart_dma_tx_use = false;
+       }
+}
+
 static int lpuart_startup(struct uart_port *port)
 {
        struct lpuart_port *sport = container_of(port, struct lpuart_port, 
port);
@@ -1471,14 +1491,7 @@ static int lpuart_startup(struct uart_port *port)
                sport->lpuart_dma_rx_use = false;
        }
 
-       if (sport->dma_tx_chan && !lpuart_dma_tx_request(port)) {
-               init_waitqueue_head(&sport->dma_wait);
-               sport->lpuart_dma_tx_use = true;
-               temp = readb(port->membase + UARTCR5);
-               writeb(temp | UARTCR5_TDMAS, port->membase + UARTCR5);
-       } else {
-               sport->lpuart_dma_tx_use = false;
-       }
+       lpuart_tx_dma_startup(port);
 
        spin_unlock_irqrestore(&sport->port.lock, flags);
 
@@ -1522,14 +1535,7 @@ static int lpuart32_startup(struct uart_port *port)
                sport->lpuart_dma_rx_use = false;
        }
 
-       if (sport->dma_tx_chan && !lpuart_dma_tx_request(port)) {
-               init_waitqueue_head(&sport->dma_wait);
-               sport->lpuart_dma_tx_use = true;
-               temp = lpuart32_read(&sport->port, UARTBAUD);
-               lpuart32_write(&sport->port, temp | UARTBAUD_TDMAE, UARTBAUD);
-       } else {
-               sport->lpuart_dma_tx_use = false;
-       }
+       lpuart_tx_dma_startup(port);
 
        if (sport->lpuart_dma_rx_use) {
                /* RXWATER must be 0 */
@@ -2581,20 +2587,7 @@ static int lpuart_resume(struct device *dev)
                }
        }
 
-       if (sport->dma_tx_chan && !lpuart_dma_tx_request(&sport->port)) {
-               init_waitqueue_head(&sport->dma_wait);
-               sport->lpuart_dma_tx_use = true;
-               if (lpuart_is_32(sport)) {
-                       temp = lpuart32_read(&sport->port, UARTBAUD);
-                       lpuart32_write(&sport->port,
-                                      temp | UARTBAUD_TDMAE, UARTBAUD);
-               } else {
-                       writeb(readb(sport->port.membase + UARTCR5) |
-                               UARTCR5_TDMAS, sport->port.membase + UARTCR5);
-               }
-       } else {
-               sport->lpuart_dma_tx_use = false;
-       }
+       lpuart_tx_dma_startup(sport);
 
        if (lpuart_is_32(sport)) {
                if (sport->lpuart_dma_rx_use) {
-- 
2.21.0