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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Tue, 22 Jun 2021 10:17:28 +0200
Message-ID: <CAMuHMdUGXu8yj3JWKwM8mt7axkrzGMiowC1t0PHrbpxRCBME3w@mail.gmail.com>
Subject: Re: [PATCH] dt-bindings: Drop redundant minItems/maxItems
To:     Rob Herring <robh@kernel.org>
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Precedence: bulk

Hi Rob,

On Tue, Jun 15, 2021 at 9:16 PM Rob Herring <robh@kernel.org> wrote:
> If a property has an 'items' list, then a 'minItems' or 'maxItems' with the
> same size as the list is redundant and can be dropped. Note that is DT
> schema specific behavior and not standard json-schema behavior. The tooling
> will fixup the final schema adding any unspecified minItems/maxItems.
>
> This condition is partially checked with the meta-schema already, but
> only if both 'minItems' and 'maxItems' are equal to the 'items' length.
> An improved meta-schema is pending.

> Signed-off-by: Rob Herring <robh@kernel.org>

> --- a/Documentation/devicetree/bindings/net/stm32-dwmac.yaml
> +++ b/Documentation/devicetree/bindings/net/stm32-dwmac.yaml
> @@ -46,7 +46,6 @@ properties:
>
>    clocks:
>      minItems: 3
> -    maxItems: 5
>      items:
>        - description: GMAC main clock
>        - description: MAC TX clock

While resolving the conflict with commit fea99822914039c6
("dt-bindings: net: document ptp_ref clk in dwmac") in soc/for-next,
I noticed the following construct for clock-names:

  clock-names:
    minItems: 3
    maxItems: 6
    contains:
      enum:
        - stmmaceth
        - mac-clk-tx
        - mac-clk-rx
        - ethstp
        - eth-ck
        - ptp_ref

Should this use items instead of enum, and drop maxItems, or is this
a valid construct to support specifying the clocks in random order?
If the latter, it does mean that the order of clock-names may not
match the order of the clock descriptions.

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