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Date:   Thu, 04 May 2023 14:22:13 +0200
From:   m.brock@vanmierlo.com
To:     Manikanta Guntupalli <manikanta.guntupalli@amd.com>
Cc:     gregkh@linuxfoundation.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, michal.simek@xilinx.com,
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        manion05gk@gmail.com
Subject: Re: [PATCH 0/2] Add rs485 support to uartps driver
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Manikanta Guntupalli wrote 2023-04-26 14:29:
> Add optional gpio property to uartps node to support rs485
> Add rs485 support to uartps driver
> 
> Manikanta Guntupalli (2):
>   dt-bindings: Add optional gpio property to uartps node to support
>     rs485
>   tty: serial: uartps: Add rs485 support to uartps driver
> 
>  .../devicetree/bindings/serial/cdns,uart.yaml |  5 +
>  drivers/tty/serial/xilinx_uartps.c            | 96 ++++++++++++++++++-
>  2 files changed, 100 insertions(+), 1 deletion(-)

Why would you want to use a GPIO and not RTS for choosing the direction
as is more common in this case?
And have you thought about configuring the polarity?
How long will the signal be active before the real transmission begins
so the driver can settle?

Maarten