Re: [PATCH v4 3/6] dt-bindings: serial: add binding for rs485 rx-enable state when rs485 is disabled

Quentin Schulz
2024-01-29T12:27:27Z

Hi Conor,

On 1/28/24 18:38, Conor Dooley wrote:
> On Fri, Jan 26, 2024 at 03:55:12PM +0100, Farouk Bouabid wrote:
>> RS485 can have a receiver-enable gpio (rx-enable-gpios). When rs485 is
>> enabled, this gpio, if provided, must be driven active while receiving.
>> However when RS485 is disabled this gpio should not have an undefined
>> state. In that case, as DE and RE pins can be connected both to this gpio,
>> if its state is not properly defined, can cause unexpected transceiver
>> behavior.
>> This binding depend on rx-enable-gpios to be implemented.
>
> Why do you need a dedicated property for this when there exists a device
> specific compatible for the uart on both of the affected rockchip
> systems?
>

This has nothing to do with Rockchip's IP but the HW design of our
carrierboard, so using the "rockchip,px30-uart" for that (which I assume
is what was suggested here?) is incorrect since it'll also apply to
PX30, RK3399 and RK3588-based Q7 SoCs we manufacture.

Did I understand the suggestion correctly?

Cheers,
Quentin