--- /dev/null
+From c9f6613b16123989f2c3bd04b1d9b2365d6914e7 Mon Sep 17 00:00:00 2001
+From: Mathieu Othacehe <othacehe@gnu.org>
+Date: Thu, 8 Aug 2024 08:06:37 +0200
+Subject: tty: atmel_serial: use the correct RTS flag.
+
+From: Mathieu Othacehe <othacehe@gnu.org>
+
+commit c9f6613b16123989f2c3bd04b1d9b2365d6914e7 upstream.
+
+In RS485 mode, the RTS pin is driven high by hardware when the transmitter
+is operating. This behaviour cannot be changed. This means that the driver
+should claim that it supports SER_RS485_RTS_ON_SEND and not
+SER_RS485_RTS_AFTER_SEND.
+
+Otherwise, when configuring the port with the SER_RS485_RTS_ON_SEND, one
+get the following warning:
+
+kern.warning kernel: atmel_usart_serial atmel_usart_serial.2.auto:
+ttyS1 (1): invalid RTS setting, using RTS_AFTER_SEND instead
+
+which is contradictory with what's really happening.
+
+Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>
+Cc: stable <stable@kernel.org>
+Tested-by: Alexander Dahl <ada@thorsis.com>
+Fixes: af47c491e3c7 ("serial: atmel: Fill in rs485_supported")
+Link: https://lore.kernel.org/r/20240808060637.19886-1-othacehe@gnu.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/serial/atmel_serial.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/tty/serial/atmel_serial.c
++++ b/drivers/tty/serial/atmel_serial.c
+@@ -2539,7 +2539,7 @@ static const struct uart_ops atmel_pops
+ };
+
+ static const struct serial_rs485 atmel_rs485_supported = {
+- .flags = SER_RS485_ENABLED | SER_RS485_RTS_AFTER_SEND | SER_RS485_RX_DURING_TX,
++ .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RX_DURING_TX,
+ .delay_rts_before_send = 1,
+ .delay_rts_after_send = 1,
+ };