Re: [PATCH 1/2] dt-bindings: serial: rs485: add rs485-mux-gpios binding

From: Krzysztof Kozlowski
Date: Tue Nov 21 2023 - 02:52:55 EST


On 20/11/2023 16:10, Rasmus Villemoes wrote:
> Some boards are capable of both rs232 and rs485, and control which
> external terminals are active via a gpio-controlled mux. Allow
> describing that gpio in DT so that the kernel can transparently handle
> the proper setting when the uart is switched between rs232 and rs485
> modes.
>
> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/serial/rs485.yaml | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/serial/rs485.yaml b/Documentation/devicetree/bindings/serial/rs485.yaml
> index 9418fd66a8e9..e8136c7d22ed 100644
> --- a/Documentation/devicetree/bindings/serial/rs485.yaml
> +++ b/Documentation/devicetree/bindings/serial/rs485.yaml
> @@ -61,6 +61,11 @@ properties:
> the active state enables RX during TX.
> maxItems: 1
>
> + rs485-mux-gpios:
> + description: GPIO pin to control muxing of the SOC signals to the RS485
> + transceiver.
> + maxItems: 1

Aren't you duplicating
https://lore.kernel.org/all/3Nk.ZZrp.5w3Yn0Ecy5C.1bMzDp@xxxxxxxxx/ ?

Anyway, similar comments: this does not look like generic RS485
property. Are you saying that standard defines such GPIO?


Best regards,
Krzysztof