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Date:   Sun, 17 Apr 2022 19:45:52 +0200
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Subject: Re: [PATCH 2/2] arm64: dts: rockchip: Add Hardkernel ODROID-M1 board
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To:     Peter Geis <pgwipeout@gmail.com>
Cc:     Dongjin Kim <tobetter@gmail.com>, Heiko Stuebner <heiko@sntech.de>,
        devicetree <devicetree@vger.kernel.org>,
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From:   Krzysztof Kozlowski <krzk@kernel.org>
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On 16/04/2022 14:07, Peter Geis wrote:

>>> +     dc_12v: dc-12v {
>>
>> Generic node name, so "regulator" or "regulator-0"
> 
> Unfortunately, this advice breaks the regulator-fixed driver, which it
> seems cannot cope with a bunch of nodes all named "regulator".

What exactly cannot cope? You cannot have different device nodes with
the same name but this is not a limitation of regulator but devicetree spec.

> Setting the regulators as regulator-0 -1 -2 leads to fun issues where
> the regulator numbering in the kernel doesn't match the node numbers.

There are no "node numbers"... maybe you mean unit addresses? But there
are none here.

> It also makes it more fun when additional regulators need to be added
> and everything gets shuffled around.

Usually adding - in subsequent DTS files - means increasing the numbers
so if you have regulator-[012] then just use regulator-[345] in other
files. I see potential mess when you combine several DTSI files, each
defining regulators, so in such case "some-name-regulator" (or reversed)
is also popular approach.

> If naming these uniquely to avoid confusion and collisions is such an
> issue, why is it not caught by make W=1 dtbs_check?

Patches are welcome. :)

Best regards,
Krzysztof