Re: [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in STM32 UART

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Mani,

On Mon, Apr 20, 2020 at 7:02 PM <mani@kernel.org> wrote:
> From: Manivannan Sadhasivam <mani@kernel.org>
>
> Document the use of CTS/RTS gpios for flow control in STM32 UART
> controller. These properties can be used instead of 'st,hw-flow-ctrl'
> for making use of any gpio pins for flow control instead of dedicated
> pins. It should be noted that both CTS/RTS and 'st,hw-flow-ctrl'
> properties cannot co-exist in a design.
>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>

> --- a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml
> +++ b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml

> @@ -55,6 +61,14 @@ properties:
>    linux,rs485-enabled-at-boot-time: true
>    rs485-rx-during-tx: true
>
> +if:
> +  required:
> +    - st,hw-flow-ctrl

Perhaps "st,hw-flow-ctrl" should be deprecated, in favor of the standard
"uart-has-rtscts" property?
Of course the driver needs to gain support for the latter first.

> +then:
> +  properties:
> +    cts-gpios: false
> +    rts-gpios: false
> +
>  required:
>    - compatible
>    - reg

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds