[PATCH 4/7] serial: imx: Simplify DMA disablement

From: Romain Perier
Date: Fri Jun 30 2017 - 08:06:28 EST


From: Nandor Han <nandor.han@xxxxxx>

This commits simplify the function imx_disable_dma() by moving
the code for disabling RX and TX DMAs to dedicated functions.
Also move away CTSC and CTS as this is not related to DMA.

Signed-off-by: Nandor Han <nandor.han@xxxxxx>
Signed-off-by: Romain Perier <romain.perier@xxxxxxxxxxxxx>
---
drivers/tty/serial/imx.c | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 81fb413..e8cf7cf 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1208,6 +1208,24 @@ static int imx_uart_dma_init(struct imx_port *sport)
return ret;
}

+static void imx_stop_tx_dma(struct imx_port *sport)
+{
+ unsigned long temp;
+
+ temp = readl(sport->port.membase + UCR1);
+ temp &= ~UCR1_TDMAEN;
+ writel(temp, sport->port.membase + UCR1);
+}
+
+static void imx_stop_rx_dma(struct imx_port *sport)
+{
+ unsigned long temp;
+
+ temp = readl(sport->port.membase + UCR1);
+ temp &= ~(UCR1_RDMAEN | UCR1_ATDMAEN);
+ writel(temp, sport->port.membase + UCR1);
+}
+
static void imx_enable_dma(struct imx_port *sport)
{
unsigned long temp;
@@ -1233,17 +1251,8 @@ static void imx_enable_dma(struct imx_port *sport)

static void imx_disable_dma(struct imx_port *sport)
{
- unsigned long temp;
-
- /* clear UCR1 */
- temp = readl(sport->port.membase + UCR1);
- temp &= ~(UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN);
- writel(temp, sport->port.membase + UCR1);
-
- /* clear UCR2 */
- temp = readl(sport->port.membase + UCR2);
- temp &= ~(UCR2_CTSC | UCR2_CTS | UCR2_ATEN);
- writel(temp, sport->port.membase + UCR2);
+ imx_stop_rx_dma(sport);
+ imx_stop_tx_dma(sport);

imx_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);

--
1.8.3.1