[PATCH 6.0 093/862] serial: ar933x: Deassert Transmit Enable on ->rs485_config()

From: Greg Kroah-Hartman
Date: Wed Oct 19 2022 - 04:45:27 EST


From: Lukas Wunner <lukas@xxxxxxxxx>

commit 3a939433ddc1bab98be028903aaa286e5e7461d7 upstream.

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@xxxxxxxxxxxxxxx # v5.7+
Cc: Daniel Golle <daniel@xxxxxxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Link: https://lore.kernel.org/r/5b36af26e57553f084334666e7d24c7fd131a01e.1662887231.git.lukas@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/ar933x_uart.c | 7 +++++++
1 file changed, 7 insertions(+)

--- 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
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;
}