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Date:   Thu, 04 May 2023 14:14:33 +0200
From:   m.brock@vanmierlo.com
To:     "Guntupalli, Manikanta" <manikanta.guntupalli@amd.com>
Cc:     Rob Herring <robh@kernel.org>, gregkh@linuxfoundation.org,
        krzysztof.kozlowski+dt@linaro.org, michal.simek@xilinx.com,
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        "Simek, Michal" <michal.simek@amd.com>,
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        "Datta, Shubhrajyoti" <shubhrajyoti.datta@amd.com>,
        "Goud, Srinivas" <srinivas.goud@amd.com>, manion05gk@gmail.com
Subject: Re: [PATCH 1/2] dt-bindings: Add optional gpio property to uartps
 node to support rs485
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Guntupalli, Manikanta wrote 2023-05-02 12:14:
>> > +  txrx-gpios:
>> > +    description: Optional GPIO to switch transmit and receive modes via
>> pmod.
>> 
>> What's pmod?
> Pmod is galvanically-isolated RS-485/RS-422 transceivers with a
> built-in isolated DC-DC converter, that eliminates the need for a
> separate isolated power supply in space constrained isolated designs.

AFAIK Pmod is an open standard connector by Digilent and present on many 
Xilinx
demo boards. It does not involve any galvanic isolation.
https://digilent.com/reference/_media/reference/pmod/pmod-interface-specification-1_3_1.pdf

The ISOW14x2 on the particular board you're using does however give 
isolation.
But you cannot name that board Pmod.

Maarten