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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Mon, 6 Nov 2023 14:12:36 +0100
Message-ID: <CACRpkdYW-xmejyOo9H9XSkcabvYgBqPvpjppvNe_RF6RLxyxKA@mail.gmail.com>
Subject: Re: [RFC v5 5/5] dt-bindings: firmware: arm,scmi: Add support for
 pinctrl protocol
To:     Oleksii Moisieiev <Oleksii_Moisieiev@epam.com>
Cc:     "sudeep.holla@arm.com" <sudeep.holla@arm.com>,
        Cristian Marussi <cristian.marussi@arm.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>,
        Takahiro Akashi <takahiro.akashi@linaro.org>
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On Fri, Oct 27, 2023 at 8:28=E2=80=AFAM Oleksii Moisieiev
<Oleksii_Moisieiev@epam.com> wrote:

> +                keys_pins: keys-pins {
> +                    pins =3D "GP_5_17", "GP_5_20", "GP_5_22", "GP_2_1";
> +                    bias-pull-up;
> +                };

This is kind of interesting and relates to my question about naming groups =
and
functions of GPIO pins.

Here we see four pins suspiciously named "GP_*" which I read as
"generic purpose"
and they are not muxed to *any* function, yes pulled up.

I would have expected something like:

keys_pins: keys-pins {
  groups =3D "GP_5_17_grp", "GP_5_20_grp", "GP_5_22_grp", "GP_2_1_grp";
  function =3D "gpio";
  pins =3D "GP_5_17", "GP_5_20", "GP_5_22", "GP_2_1";
  bias-pull-up;
};

I hope this illustrates what I see as a problem in not designing in
GPIO as an explicit
function, I get the impression that these pins are GPIO because it is hardw=
are
default.

Yours,
Linus Walleij