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From:   Chunyan Zhang <zhang.lyra@gmail.com>
Date:   Thu, 30 Sep 2021 11:12:28 +0800
Message-ID: <CAAfSe-tJMvYyvtOArsAW9Y980y_qzUgHoaQsyqnO6W47f9jMNA@mail.gmail.com>
Subject: Re: [PATCH 1/2] regulator: Add Unisoc's SC2730 regulator driver
To:     Mark Brown <broonie@kernel.org>
Cc:     Liam Girdwood <lgirdwood@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        DTML <devicetree@vger.kernel.org>,
        Baolin Wang <baolin.wang7@gmail.com>,
        Orson Zhai <orsonzhai@gmail.com>,
        Chunyan Zhang <chunyan.zhang@unisoc.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Lee Jones <lee.jones@linaro.org>
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+Lee Jones

On Wed, 29 Sept 2021 at 20:30, Mark Brown <broonie@kernel.org> wrote:
>
> On Wed, Sep 29, 2021 at 04:20:37PM +0800, Chunyan Zhang wrote:
> > On Tue, 28 Sept 2021 at 19:31, Mark Brown <broonie@kernel.org> wrote:
>
> > > Since this is a part of a MFD I'd not expect it to have a compatible
> > > string?
>
> > Since we switched to use devm_of_platform_populate() [1] to register
> > MFD subdevices, compatible is required, IIUC.
>
> I'm not sure that's a good fit for these regulators, we don't gain any
> extra information from the compatible here.

Humm... regulators cannot be probed without compatible for this case,
except we have a list of mfd_cells which include compatible and driver
name in sc27xx_spi (mfd) driver.

On different platforms, sc27xx_spi consists of different sub-devices
with different compatible string, to avoid adding mfd_cells to
sc27xx_spi driver each time we add a new platform support, we changed
to use devm_of_platform_populate() which can automatically register
sun-devices listed in devicetree.

The above is my understand, please correct me if I'm missing something
@Lee Jones

Thanks,
Chunyan

[1] https://lkml.org/lkml/2020/6/19/207