Subject: Re: [PATCH net-next v2 4/5] dt-bindings: dpll: add ref-sync-sources property

From: Rob Herring <[email-masked]>
Date: Tue, 7 Apr 2026 15:18:49 -0500

On Sat, Mar 28, 2026 at 09:06:23AM +0100, Ivan Vecera wrote:
> Add ref-sync-sources phandle-array property to the dpll-pin schema
> allowing board designers to declare which input pins can serve as
> sync sources in a Reference-Sync pair.  A Ref-Sync pair consists of
> a clock reference and a low-frequency sync signal where the DPLL locks
> to the clock but phase-aligns to the sync reference.
> 
> Update both examples in the Microchip ZL3073x binding to demonstrate
> the new property with a 1 PPS sync source paired to a clock source.
> 
> Reviewed-by: Petr Oros <[email-masked]>
> Reviewed-by: Prathosh Satish <[email-masked]>
> Signed-off-by: Ivan Vecera <[email-masked]>
> ---
>  .../devicetree/bindings/dpll/dpll-pin.yaml    | 11 +++++++
>  .../bindings/dpll/microchip,zl30731.yaml      | 30 ++++++++++++++-----
>  2 files changed, 34 insertions(+), 7 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dpll/dpll-pin.yaml b/Documentation/devicetree/bindings/dpll/dpll-pin.yaml
> index 51db93b77306f..7084f102e274c 100644
> --- a/Documentation/devicetree/bindings/dpll/dpll-pin.yaml
> +++ b/Documentation/devicetree/bindings/dpll/dpll-pin.yaml
> @@ -36,6 +36,17 @@ properties:
>      description: String exposed as the pin board label
>      $ref: /schemas/types.yaml#/definitions/string
>  
> +  ref-sync-sources:
> +    description: |
> +      List of phandles to input pins that can serve as the sync source
> +      in a Reference-Sync pair with this pin acting as the clock source.
> +      A Ref-Sync pair consists of a clock reference and a low-frequency
> +      sync signal.  The DPLL locks to the clock reference but
> +      phase-aligns to the sync reference.
> +      Only valid for input pins.  Each referenced pin must be a
> +      different input pin on the same device.
> +    $ref: /schemas/types.yaml#/definitions/phandle-array

phandle-array is really a matrix. As there are no arg cells here, for 
a list of phandles you need:

items:
  maxItems: 1

With that,

Reviewed-by: Rob Herring (Arm) <[email-masked]>

Rob