[PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled

[Jiada Wang]

From: Anton Bondarenko <anton_bondarenko@xxxxxxxxxx>

DMA mode for UART can be used even w/o HW flow control with RTS/CTS.
So it need to be initialized and enabled earlier.

Signed-off-by: Anton Bondarenko <anton_bondarenko@xxxxxxxxxx>
Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
---
 drivers/tty/serial/imx.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index d501628..a0f27b4 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1173,12 +1173,20 @@ static int imx_startup(struct uart_port *port)
 		}
 	}
 
+	/* Can we enable the DMA support? */
+	if (is_imx6q_uart(sport) && !uart_console(port) &&
+	    !sport->dma_is_inited)
+		imx_uart_dma_init(sport);
+
 	spin_lock_irqsave(&sport->port.lock, flags);
 	/*
 	 * Finally, clear and enable interrupts
 	 */
 	writel(USR1_RTSD, sport->port.membase + USR1);
 
+	if (sport->dma_is_inited && !sport->dma_is_enabled)
+		imx_enable_dma(sport);
+
 	temp = readl(sport->port.membase + UCR1);
 	temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
 
@@ -1378,11 +1386,6 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		if (sport->have_rtscts) {
 			ucr2 &= ~UCR2_IRTS;
 			ucr2 |= UCR2_CTSC;
-
-			/* Can we enable the DMA support? */
-			if (is_imx6q_uart(sport) && !uart_console(port)
-				&& !sport->dma_is_inited)
-				imx_uart_dma_init(sport);
 		} else {
 			termios->c_cflag &= ~CRTSCTS;
 		}
@@ -1504,8 +1507,6 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
 		imx_enable_ms(&sport->port);
 
-	if (sport->dma_is_inited && !sport->dma_is_enabled)
-		imx_enable_dma(sport);
 	spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
-- 
1.9.3

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