Re: [net-next 1/3] dt-bindings: ptp: renesas,rcar-gen4-gptp: Add binding for R-Car Gen4

[Krzysztof Kozlowski]

On 09/06/2026 23:57, Niklas Söderlund wrote:
> Add bindings for the R-Car Gen4 gPTP timer. The timer enables accurate
> synchronization of the clock in the control system. The timer is
> system-wide and used by different Ethernet devices on each Gen4 platform.

A nit, subject: drop second/last, redundant "binding for". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.17-rc3/source/Documentation/devicetree/bindings/submitting-patches.rst#L18


> 
>   - On R-Car S4 it is shared between RSWITCH and RAVB.
> 
>   - On R-Car V4H it is shared between RTSN and RAVB.
> 
>   - On R-Car V4M it is only used by RAVB.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
>  .../bindings/ptp/renesas,rcar-gen4-gptp.yaml  | 64 +++++++++++++++++++
>  MAINTAINERS                                   |  6 ++
>  2 files changed, 70 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml
> 
> diff --git a/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml b/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml
> new file mode 100644
> index 000000000000..99e6e3ca73b6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ptp/renesas,rcar-gen4-gptp.yaml
> @@ -0,0 +1,64 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +# Copyright (C) 2026 Renesas Electronics Corp.
> +# Copyright (C) 2026 Niklas Söderlund <niklas.soderlund@xxxxxxxxxxxx>
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/ptp/renesas,rcar-gen4-gptp.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas R-Car Gen4 gPTP timer
> +
> +maintainers:
> +  - Niklas Söderlund <niklas.soderlund@xxxxxxxxxxxx>
> +
> +description:
> +  The R-Car Gen4 gPTP timer enables accurate synchronization of the clock in
> +  the control system. The timer is system-wide and used by different Ethernet
> +  devices on each Gen4 platform.
> +
> +    - On R-Car S4 it is shared between RSWITCH and RAVB.
> +    - On R-Car V4H it is shared between RTSN and RAVB.
> +    - On R-Car V4M it is only used by RAVB.
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - renesas,r8a779f0-gptp # S4-8
> +          - renesas,r8a779g0-gptp # V4H
> +          - renesas,r8a779h0-gptp # V4M
> +      - const: renesas,rcar-gen4-gptp # Generic R-Car Gen4

Please drop comment or drop generic compatible and make it specific.
Generic compatibles are discouraged, so don't advertise that. Look how
other RECENT Renesas bindings do it.

> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  power-domains:
> +    maxItems: 1
> +
> +  resets:
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - power-domains
> +  - resets
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/r8a779g0-cpg-mssr.h>
> +    #include <dt-bindings/power/r8a779g0-sysc.h>
> +
> +    gptp: gptp@e6449000 {

Drop unused label. Node name usually is "phc". Could be "ptp", but not
"gptp". What is gptp in generic names?

>  L:	linux-iio@xxxxxxxxxxxxxxx


Best regards,
Krzysztof