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References: <20210120080522.471120-1-saravanak@google.com> <20210120080522.471120-2-saravanak@google.com>
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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Thu, 21 Jan 2021 14:11:24 +0100
Message-ID: <CACRpkdbEC6duR=fJQD_Nw9o=HW0DEe2_Ks3SYCgJmkOjzKz3Jg@mail.gmail.com>
Subject: Re: [PATCH v1 1/2] of: property: Add fw_devlink support for "gpio"
 and "gpios" binding
To:     Saravana Kannan <saravanak@google.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-tegra <linux-tegra@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Jon Hunter <jonathanh@nvidia.com>,
        Marc Zyngier <maz@kernel.org>,
        Kevin Hilman <khilman@baylibre.com>,
        Android Kernel Team <kernel-team@android.com>
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Precedence: bulk

On Wed, Jan 20, 2021 at 9:05 AM Saravana Kannan <saravanak@google.com> wrote:

> To provide backward compatibility for boards that use deprecated DT
> bindings, we need to add fw_devlink support for "gpio" and "gpios".

You do some more stuff in the patch so describe that too.
Especially the check for hogs and #gpio-cells.
Describe why you do that. Maybe even with a comment in
the code because I don't think everyone will understand.

> +       if (strcmp(prop_name, "gpio") && strcmp(prop_name, "gpios"))
> +               return NULL;

This part is easy to understand.

> +       if (of_find_property(np, "gpio-hog", NULL))
> +               return NULL;
> +
> +       if (of_parse_phandle_with_args(np, prop_name, "#gpio-cells", index,
> +                                      &sup_args))
> +               return NULL;

This part is hard to understand. Insert comments and tell the reader
of the code what is going on and why.

Yours,
Linus Walleij