[Linux-stm32] Move RS485 implementation from drivers to serial core (v4 RESEND)

[Lukas Wunner]

On Sun, Apr 10, 2022 at 12:46:33PM +0200, Lino Sanfilippo wrote:
> This patch series is an attempt to simplify rs485 implementation in drivers
> by moving the following tasks out of the drivers into the serial core:
> 
> - ensure sane RTS settings: in case of an invalid configuration (both RTS
>   after send and RTS on send set or both unset) enable RTS on send and
>   disable RTS after send
[...]
> Redundant code has been removed from the following drivers for now:
> 
> - atmel
> - fsl_lpuart
> - amba
> - imx
> - max310x
> - omap-serial
> - sc16is7xx
> - stm32-usart

It looks like there's more of this cruft left at least in
serial8250_em485_config()...

Thanks,

Lukas