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Date:   Sun, 28 Aug 2022 16:04:49 +0200
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Subject: Re: [RFC PATCH v1 12/14] nvmem: layouts: rewrite the u-boot-env
 driver as a NVMEM layout
To:     Michael Walle <michael@walle.cc>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Shawn Guo <shawnguo@kernel.org>, Li Yang <leoyang.li@nxp.com>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Frank Rowand <frowand.list@gmail.com>
Cc:     linux-mtd@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        netdev@vger.kernel.org, Ahmad Fatoum <a.fatoum@pengutronix.de>
References: <20220825214423.903672-1-michael@walle.cc>
 <20220825214423.903672-13-michael@walle.cc>
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On 25.08.2022 23:44, Michael Walle wrote:
> Instead of hardcoding the underlying access method mtd_read() and
> duplicating all the error handling, rewrite the driver as a nvmem
> layout which just uses nvmem_device_read() and thus works with any
> NVMEM device.
> 
> But because this is now not a device anymore, the compatible string
> will have to be changed so the device will still be probed:
>    compatible = "u-boot,env";
> to
>    compatible = "u-boot,env", "nvmem-cells";
> 
> "nvmem-cells" will tell the mtd layer to register a nvmem_device().
> "u-boot,env" will tell the NVMEM that it should apply the u-boot
> environment layout to the NVMEM device.

That's fishy but maybe we can ignore backward compatibility at
point.

Still you need to update DT binding.