[PATCH 2/6] dt-bindings: serial: Add clock-frequency property as an alternative to clocks

[Krzysztof Kozlowski]

On 11/08/2025 17:19, Andrea della Porta wrote:
> The UARTA controller on BCM2712 connected to Bluetooth chip does not

Bluetooth chip does not ask...

> mandiatorily ask for a clock connected to the high speed baud generator.
> This is, in fact, an optional clock in the driver.

... or driver does not ask?

Please describe here hardware.


> 
> As an alternative, the call to uart_read_port_properties() ensures that
> just a simple 'clock-frequency' property can be specified for the clock
> value.

Don't describe drivers. Describe hardware.

> 
> Amend the bindings to allow to either specify clocks or clock-frequency.
> 
> Signed-off-by: Andrea della Porta <andrea.porta at suse.com>
> ---
>  .../bindings/serial/brcm,bcm7271-uart.yaml    | 19 +++++++++++++++++--

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching. For bindings, the preferred subjects are
explained here:
https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters


>  1 file changed, 17 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml b/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
> index 89c462653e2d..96697b1428bd 100644
> --- a/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
> +++ b/Documentation/devicetree/bindings/serial/brcm,bcm7271-uart.yaml
> @@ -40,7 +40,15 @@ properties:
>            - const: dma_tx
>            - const: dma_intr2
>  
> +  clock-frequency:
> +    description:
> +      The input clock frequency for the UART, Either this or clocks must be
> +      specified.

Anyway, don't open-code schema in free form text.

That's legacy property. You need clear explanation why.

> +
>    clocks:
> +    description:
> +      High speed baud rate clock. Either this or clock-frequency must be
> +      specified.

Drop last sentence, Anyway, don't open-code schema in free form text.
First sentence seems redundant anyway.


>      minItems: 1

I'll fix this.

>  
>    clock-names:
> @@ -61,11 +69,18 @@ required:
>    - compatible
>    - reg
>    - reg-names
> -  - clocks
> -  - clock-names
>    - interrupts
>    - interrupt-names
>  
> +oneOf:
> +  - allOf:
> +      - required:
> +          - clocks
> +      - required:
> +          - clock-names
> +  - required:
> +      - clock-frequency
> +
>  unevaluatedProperties: false
>  
>  examples:


Best regards,
Krzysztof