serial: uartps: Enable automatic flow control

Enable automatic flow control which should ensure that there is no
mainteinance in connection for zcu100 BT case.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 0443edc1ad78..71c032744dae 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1006,13 +1006,12 @@ static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
         val = readl(port->membase + CDNS_UART_MODEMCR);
         mode_reg = readl(port->membase + CDNS_UART_MR);
 
-        val &= ~(CDNS_UART_MODEMCR_RTS | CDNS_UART_MODEMCR_DTR);
+        val &= ~(CDNS_UART_MODEMCR_RTS | CDNS_UART_MODEMCR_DTR |
+                 CDNS_UART_MODEMCR_FCM);
         mode_reg &= ~CDNS_UART_MR_CHMODE_MASK;
 
-        if (mctrl & TIOCM_RTS)
-                val |= CDNS_UART_MODEMCR_RTS;
-        if (mctrl & TIOCM_DTR)
-                val |= CDNS_UART_MODEMCR_DTR;
+        if (mctrl & TIOCM_RTS || mctrl & TIOCM_DTR)
+                val |= CDNS_UART_MODEMCR_FCM;
         if (mctrl & TIOCM_LOOP)
                 mode_reg |= CDNS_UART_MR_CHMODE_L_LOOP;
         else