serial: ar933x: Deassert Transmit Enable on ->rs485_config()

The ar933x_uart driver neglects to deassert Transmit Enable when
->rs485_config() is invoked.  Fix it.

Fixes: 9be1064fe524 ("serial: ar933x_uart: add RS485 support")
Cc: stable@vger.kernel.org # v5.7+
Cc: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/5b36af26e57553f084334666e7d24c7fd131a01e.1662887231.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 0a4020dba165c29b9bc93ff55c6492f54a5623e1..925484a42c821e8ea70acbefe443b164f5001d4e 100644 (file)
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -583,6 +583,13 @@ static const struct uart_ops ar933x_uart_ops = {
 static int ar933x_config_rs485(struct uart_port *port, struct ktermios *termios,
                                struct serial_rs485 *rs485conf)
 {
+       struct ar933x_uart_port *up =
+                       container_of(port, struct ar933x_uart_port, port);
+
+       if (port->rs485.flags & SER_RS485_ENABLED)
+               gpiod_set_value(up->rts_gpiod,
+                       !!(rs485conf->flags & SER_RS485_RTS_AFTER_SEND));
+
        return 0;
 }