MLK-12161 tty: serial: imx: only enable RTSD interrupt for hw flow control

Only enable RTSD interrupt for hw flow control, otherwise RTS_B signal
has some external signal disturbance without config RTS_B select input.

Signed-off-by: Fugang Duan <B38611@freescale.com>
(cherry picked from commit: 471e8c43aca3)

Conflicts:
	drivers/tty/serial/imx.c

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 3ed0a88..2378885 100644 (file)
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1285,7 +1285,9 @@ static int imx_startup(struct uart_port *port)
        temp = readl(sport->port.membase + UCR1);
        if (!sport->dma_is_inited)
                temp |= UCR1_RRDYEN;
-       temp |= UCR1_RTSDEN | UCR1_UARTEN;
+       if (sport->have_rtscts)
+               temp |= UCR1_RTSDEN;
+       temp |= UCR1_UARTEN;
        writel(temp, sport->port.membase + UCR1);
 
        temp = readl(sport->port.membase + UCR4);