If the RS485 feature RX-during-TX is supported by means of a GPIO set the according supported flag. Otherwise setting this feature from userspace may not be possible, since in uart_sanitize_serial_rs485() the passed RS485 configuration is matched against the supported features and unsupported settings are thereby removed and thus take no effect.

Cc: stable@vger.kernel.org Fixes: 163f080eb717 ("serial: core: Add option to output RS485 RX_DURING_TX state via GPIO") Signed-off-by: Lino Sanfilippo l.sanfilippo@kunbus.com --- drivers/tty/serial/serial_core.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index ef0500be3553..697c36dc7ec8 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -3622,6 +3622,8 @@ int uart_get_rs485_mode(struct uart_port *port) port->rs485_rx_during_tx_gpio = NULL; return dev_err_probe(dev, ret, "Cannot get rs485-rx-during-tx-gpios\n"); } + if (port->rs485_rx_during_tx_gpio) + port->rs485_supported.flags |= SER_RS485_RX_DURING_TX;

return 0; }