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References: <8b976cf546bad3aa159a6f05cd3c15d1@walle.cc> <20221118214036.1269005-1-michael@walle.cc>
In-Reply-To: <20221118214036.1269005-1-michael@walle.cc>
From:   Rob Herring <robh+dt@kernel.org>
Date:   Fri, 18 Nov 2022 15:52:09 -0600
Message-ID: <CAL_JsqKnuycUSHfxxcZMcidELA-ttZUv5NhV5ApkpUQMsc-aQQ@mail.gmail.com>
Subject: Re: [PATCH] of: property: special #nvmem-cell-cells handling
To:     Michael Walle <michael@walle.cc>
Cc:     Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Frank Rowand <frowand.list@gmail.com>,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        devicetree@vger.kernel.org
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On Fri, Nov 18, 2022 at 3:40 PM Michael Walle <michael@walle.cc> wrote:
>
> Since recently, there is a new #nvmem-cell-cells. To be backwards
> compatible this is optional. Therefore, we need special handling and
> cannot use DEFINE_SIMPLE_PROP() anymore.
>
> Signed-off-by: Michael Walle <michael@walle.cc>
> ---
> This patch will be part of the following series:
> https://lore.kernel.org/linux-arm-kernel/20221118185118.1190044-1-michael@walle.cc/
>
>  drivers/of/property.c | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index 967f79b59016..93c0ea662336 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1305,7 +1305,6 @@ DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells")
>  DEFINE_SIMPLE_PROP(power_domains, "power-domains", "#power-domain-cells")
>  DEFINE_SIMPLE_PROP(hwlocks, "hwlocks", "#hwlock-cells")
>  DEFINE_SIMPLE_PROP(extcon, "extcon", NULL)
> -DEFINE_SIMPLE_PROP(nvmem_cells, "nvmem-cells", NULL)
>  DEFINE_SIMPLE_PROP(phys, "phys", "#phy-cells")
>  DEFINE_SIMPLE_PROP(wakeup_parent, "wakeup-parent", NULL)
>  DEFINE_SIMPLE_PROP(pinctrl0, "pinctrl-0", NULL)
> @@ -1381,6 +1380,22 @@ static struct device_node *parse_interrupts(struct device_node *np,
>         return of_irq_parse_one(np, index, &sup_args) ? NULL : sup_args.np;
>  }
>
> +static struct device_node *parse_nvmem_cells(struct device_node *np,
> +                                            const char *prop_name, int index)
> +{
> +       struct of_phandle_args sup_args;
> +
> +       if (strcmp(prop_name, "nvmem-cells"))
> +               return NULL;
> +
> +       if (of_parse_phandle_with_optional_args(np, prop_name,
> +                                               "#nvmem-cell-cells", index,
> +                                               &sup_args))
> +               return NULL;
> +
> +       return sup_args.np;
> +}

There's a couple of other cases like that (MSI IIRC), so can we
generalize this to work in more than 1 case?

Rob