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From:   Tzung-Bi Shih <tzungbi@google.com>
Date:   Wed, 19 Aug 2020 23:42:27 +0800
Message-ID: <CA+Px+wUV89KO8JJd3+HpOrgFRSc7sdg-DBW44C31262Qx9NzVg@mail.gmail.com>
Subject: Re: [PATCH v5 2/2] dt-bindings: mediatek: mt6359: add codec document
To:     Mark Brown <broonie@kernel.org>
Cc:     Jiaxin Yu <jiaxin.yu@mediatek.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Rob Herring <robh+dt@kernel.org>,
        Takashi Iwai <tiwai@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        ALSA development <alsa-devel@alsa-project.org>,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, howie.huang@mediatek.com,
        eason.yen@mediatek.com, shane.chien@mediatek.com,
        bicycle.tsai@mediatek.com
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On Wed, Aug 19, 2020 at 6:38 PM Mark Brown <broonie@kernel.org> wrote:
>
> On Mon, Aug 17, 2020 at 04:11:03PM +0800, Tzung-Bi Shih wrote:
> > I misunderstood.  It still needs the compatible string to match the
> > corresponding driver.
>
> No, it doesn't.  The MFD should be registering the platform device.

I guess I see.  It lists the mfd_cell when calling
devm_mfd_add_devices() in drivers/mfd/mt6397-core.c.  It falls back to
use driver name and device name to match.  As long as the name
provided in mfd_cell matches the platform driver name, it works.

But I found struct mfd_cell also contains member .of_compatible.  What
is the difference if we use compatible string (as is) for this device
instead of falling back to use device name to match?