Re: [PATCH v2 02/12] dt-bindings: watchdog: Document Exynos850 watchdog bindings

[Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>]

On 31/10/2021 13:22, Sam Protsenko wrote:
> Exynos850 SoC has two CPU clusters:
>   - cluster 0: contains CPUs #0, #1, #2, #3
>   - cluster 1: contains CPUs #4, #5, #6, #7
> 
> Each cluster has its own dedicated watchdog timer. Those WDT instances
> are controlled using different bits in PMU registers, new
> "samsung,index" property is added to tell the driver which bits to use
> for defined watchdog node.
> 
> Also on Exynos850 the peripheral clock and the source clock are two
> different clocks. Provide a way to specify two clocks in watchdog device
> tree node.
> 
> Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
> ---
> Changes in v2:
>   - Stated explicitly that Exynos850 driver requires 2 clocks
>   - Used single compatible for Exynos850
>   - Added "index" property to specify CPU cluster index
>   - Fixed a typo in commit message: dedicater -> dedicated
> 
>  .../bindings/watchdog/samsung-wdt.yaml        | 44 +++++++++++++++++--
>  1 file changed, 40 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.yaml b/Documentation/devicetree/bindings/watchdog/samsung-wdt.yaml
> index 93cd77a6e92c..f29d0ca4eced 100644
> --- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.yaml
> @@ -22,25 +22,32 @@ properties:
>        - samsung,exynos5250-wdt                # for Exynos5250
>        - samsung,exynos5420-wdt                # for Exynos5420
>        - samsung,exynos7-wdt                   # for Exynos7
> +      - samsung,exynos850-wdt                 # for Exynos850
>  
>    reg:
>      maxItems: 1
>  
>    clocks:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 2
>  
>    clock-names:
> -    items:
> -      - const: watchdog
> +    minItems: 1
> +    maxItems: 2
>  
>    interrupts:
>      maxItems: 1
>  
> +  samsung,index:

Slightly more descriptive, e.g.:
samsung,cluster-index

> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Index of CPU cluster on which watchdog is running (in case of Exynos850)
> +
>    samsung,syscon-phandle:
>      $ref: /schemas/types.yaml#/definitions/phandle
>      description:
>        Phandle to the PMU system controller node (in case of Exynos5250,
> -      Exynos5420 and Exynos7).
> +      Exynos5420, Exynos7 and Exynos850).
>  
>  required:
>    - compatible
> @@ -59,9 +66,38 @@ allOf:
>                - samsung,exynos5250-wdt
>                - samsung,exynos5420-wdt
>                - samsung,exynos7-wdt
> +              - samsung,exynos850-wdt
>      then:
>        required:
>          - samsung,syscon-phandle
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - samsung,exynos850-wdt
> +    then:
> +      properties:
> +        clocks:
> +          items:
> +            - description: Bus clock, used for register interface
> +            - description: Source clock (driving watchdog counter)
> +        clock-names:
> +          items:
> +            - const: watchdog
> +            - const: watchdog_src
> +        samsung,index:
> +          enum: [0, 1]
> +      required:
> +        - samsung,index
> +    else:
> +      properties:
> +        clocks:
> +          items:
> +            - description: Bus clock, which is also a source clock
> +        clock-names:
> +          items:
> +            - const: watchdog

Also under this else:
   samsung,cluster-index: false

>  
>  unevaluatedProperties: false
>  
> 


Best regards,
Krzysztof