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References: <20211231161930.256733-1-krzysztof.kozlowski@canonical.com> <20211231161930.256733-3-krzysztof.kozlowski@canonical.com>
In-Reply-To: <20211231161930.256733-3-krzysztof.kozlowski@canonical.com>
From:   Sam Protsenko <semen.protsenko@linaro.org>
Date:   Mon, 3 Jan 2022 20:43:02 +0200
Message-ID: <CAPLW+4kVjswvcx7PjkBq_cPrmoi1_yJw9qGOO2tcRCDm27zKmA@mail.gmail.com>
Subject: Re: [PATCH 02/24] pinctrl: samsung: accept GPIO bank nodes with a suffix
To:     Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Cc:     Tomasz Figa <tomasz.figa@gmail.com>,
        Sylwester Nawrocki <s.nawrocki@samsung.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        linux-arm-kernel@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org, linux-gpio@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Sylwester Nawrocki <snawrocki@kernel.org>,
        Chanho Park <chanho61.park@samsung.com>
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Precedence: bulk

On Fri, 31 Dec 2021 at 18:20, Krzysztof Kozlowski
<krzysztof.kozlowski@canonical.com> wrote:
>
> Existing dt-bindings expected that each GPIO/pin bank within pin
> controller has its own node with name matching the bank (e.g. gpa0,
> gpx2) and "gpio-controller" property.  The node name is then used for
> matching between driver data and DTS.
>
> Newly introduced dtschema expects to have nodes ending with "-gpio-bank"
> suffix, so rewrite bank-devicetree matching to look for old and new
> style of naming.
>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
> ---
>  drivers/pinctrl/samsung/pinctrl-samsung.c | 57 ++++++++++++++++++-----
>  1 file changed, 45 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
> index f2864a7869b3..561853df8ef7 100644
> --- a/drivers/pinctrl/samsung/pinctrl-samsung.c
> +++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
> @@ -1011,13 +1011,56 @@ static void samsung_banks_of_node_put(struct samsung_pinctrl_drv_data *d)
>                 of_node_put(bank->of_node);
>  }
>
> +/*
> + * Iterate over all driver pin banks to find one matching the name of node,
> + * skipping optional "-gpio" node suffix. When found, assign node to the bank.
> + */
> +static void samsung_banks_of_node_get(struct device *dev,
> +                                     struct samsung_pinctrl_drv_data *d,
> +                                     struct device_node *node)
> +{
> +       const char *suffix = "-gpio-bank";
> +       struct samsung_pin_bank *bank;
> +       struct device_node *child;
> +       /* Pin bank names are up to 4 characters */
> +       char node_name[20];
> +       unsigned int i;
> +       size_t len;
> +
> +       bank = d->pin_banks;
> +       for (i = 0; i < d->nr_banks; ++i, ++bank) {
> +               strscpy(node_name, bank->name, sizeof(node_name));
> +               len = strlcat(node_name, suffix, sizeof(node_name));
> +               if (len == sizeof(sizeof(node_name))) {

Double sizeof is probably wrong?

> +                       dev_err(dev, "Too long pin bank name '%s', ignoring\n",
> +                               bank->name);
> +                       continue;
> +               }
> +
> +               for_each_child_of_node(node, child) {
> +                       if (!of_find_property(child, "gpio-controller", NULL))
> +                               continue;
> +                       if (of_node_name_eq(child, node_name))
> +                               break;
> +                       else if (of_node_name_eq(child, bank->name))
> +                               break;
> +               }
> +
> +               if (child)
> +                       bank->of_node = child;
> +               else
> +                       dev_warn(dev, "Missing node for bank %s - invalid DTB\n",
> +                                bank->name);
> +               /* child reference dropped in samsung_drop_banks_of_node() */
> +       }
> +}
> +
>  /* retrieve the soc specific data */
>  static const struct samsung_pin_ctrl *
>  samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
>                              struct platform_device *pdev)
>  {
>         struct device_node *node = pdev->dev.of_node;
> -       struct device_node *np;
>         const struct samsung_pin_bank_data *bdata;
>         const struct samsung_pin_ctrl *ctrl;
>         struct samsung_pin_bank *bank;
> @@ -1081,17 +1124,7 @@ samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
>          */
>         d->virt_base = virt_base[0];
>
> -       for_each_child_of_node(node, np) {
> -               if (!of_find_property(np, "gpio-controller", NULL))
> -                       continue;
> -               bank = d->pin_banks;
> -               for (i = 0; i < d->nr_banks; ++i, ++bank) {
> -                       if (of_node_name_eq(np, bank->name)) {
> -                               bank->of_node = np;
> -                               break;
> -                       }
> -               }
> -       }
> +       samsung_banks_of_node_get(&pdev->dev, d, node);
>
>         d->pin_base = pin_base;
>         pin_base += d->nr_pins;
> --
> 2.32.0
>