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Date:   Sat, 16 Jul 2022 11:30:12 +0200
From:   Michael Walle <michael@walle.cc>
To:     =?UTF-8?Q?Michal_Such=C3=A1nek?= <msuchanek@suse.de>
Cc:     Pratyush Yadav <p.yadav@ti.com>, linux-sunxi@lists.linux.dev,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
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        Jernej Skrabec <jernej.skrabec@gmail.com>,
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        Vignesh Raghavendra <vigneshr@ti.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org
Subject: Re: [PATCH 1/2] mtd: spi-nor: When a flash memory is missing do not
 report an error
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Am 2022-07-16 10:20, schrieb Michal Suchánek:

>> So if DT says there isn't a flash on a specific CS when there is, then
>> DT should be fixed to describe the flash, and then we can probe it. 
>> You
>> both seem to be saying the same thing here, and I agree.
> 
> The disagreement is about the situation when there is sometimes a flash
> chip.

No. The disagreement is what should happen if the DT says there is
a device but there isn't. Which right now is an error and it should
stay that way. Your hardware description says there is a flash
but it cannot be probed, so it is an error. What about a board
which has an actual error and the flash isn't responding? You
trade one use case for another.

Also I've looked at the PHY subsystem and there, if a PHY is described
in the DT but isn't there, the following error will be printed:
   dev_err(&mdio->dev, "MDIO device at address %d is missing.\n", addr);

And that is for a bus which can even be automatically be
probed/detected.

-michael