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Date: Tue, 20 Feb 2024 11:16:40 +0100
Message-Id: <CZ9TU33SEHWS.1HK9XLFPKBROY@walle.cc>
To: "Marco Felsch" <m.felsch@pengutronix.de>, "Miquel Raynal"
 <miquel.raynal@bootlin.com>
Subject: Re: [RFC PATCH] nvmem: core: add sysfs cell write support
Cc: <srinivas.kandagatla@linaro.org>, <gregkh@linuxfoundation.org>,
 <rafal@milecki.pl>, <linux-kernel@vger.kernel.org>, <kernel@pengutronix.de>
From: "Michael Walle" <michael@walle.cc>
References: <20240215211401.1201004-1-m.felsch@pengutronix.de>
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On Tue Feb 20, 2024 at 10:50 AM CET, Marco Felsch wrote:
> > Read-copy-update would probably work but would as well be very
> > sub-optimal. I guess we could live with it, but as for now there has
> > not been any real request for it, I'd also advise to keep this feature
> > out of the mtd world in general.
>
> SPI-NORs are very typical for storing production-data as well but as I
> said this is another story. I'm fine with limiting it to EEPROMs since
> this is my use-case :)

Right, that is just what we are doing on our boards. But we do that
in one go in our production environment, like just writing to the
mtd partition or the OTP region. The nvmem cells are then just for
connecting the devices to this information (like the nvmem-cells
property of an ethernet device).

Also usually, there is more to it, like removing write protection of
said flash (sometimes in a proprietary way).

-michael

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