serial: imx: cleanup imx_uart_disable_dma()

Remove unrelated CTSC/CTS disabling from imx_uart_disable_dma() and
move it to imx_uart_shutdown(), which is the only user of the DMA
disabling function. This should not change the driver's behaviour,
but improves readability. After this change imx_uart_disable_dma()
does the reverse thing of imx_uart_enable_dma().
Suggested-by: Nandor Han <nandor.han@ge.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/imx.c

@@ -1291,18 +1291,13 @@ static void imx_uart_enable_dma(struct imx_port *sport)
 
 static void imx_uart_disable_dma(struct imx_port *sport)
 {
-	u32 ucr1, ucr2;
+	u32 ucr1;
 
 	/* clear UCR1 */
 	ucr1 = imx_uart_readl(sport, UCR1);
 	ucr1 &= ~(UCR1_RXDMAEN | UCR1_TXDMAEN | UCR1_ATDMAEN);
 	imx_uart_writel(sport, ucr1, UCR1);
 
-	/* clear UCR2 */
-	ucr2 = imx_uart_readl(sport, UCR2);
-	ucr2 &= ~(UCR2_CTSC | UCR2_CTS | UCR2_ATEN);
-	imx_uart_writel(sport, ucr2, UCR2);
-
 	imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT);
 
 	sport->dma_is_enabled = 0;
@@ -1447,7 +1442,7 @@ static void imx_uart_shutdown(struct uart_port *port)
 
 	spin_lock_irqsave(&sport->port.lock, flags);
 	ucr2 = imx_uart_readl(sport, UCR2);
-	ucr2 &= ~(UCR2_TXEN | UCR2_ATEN);
+	ucr2 &= ~(UCR2_TXEN | UCR2_CTSC | UCR2_CTS | UCR2_ATEN);
 	imx_uart_writel(sport, ucr2, UCR2);
 	spin_unlock_irqrestore(&sport->port.lock, flags);