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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Sun, 6 Dec 2020 00:01:32 +0100
Message-ID: <CACRpkda9TfKnKSJ+yBEn6uqvAEoTFXy-g-6GqJaUQ0FYHLP3iw@mail.gmail.com>
Subject: Re: [PATCH v6 4/4] mmc: sdhci-of-arasan: Enable UHS-1 support for
 Keem Bay SOC
To:     "Zulkifli, Muhammad Husaini" <muhammad.husaini.zulkifli@intel.com>
Cc:     Ulf Hansson <ulf.hansson@linaro.org>,
        "Hunter, Adrian" <adrian.hunter@intel.com>,
        Michal Simek <michal.simek@xilinx.com>,
        linux-mmc <linux-mmc@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Shevchenko, Andriy" <andriy.shevchenko@intel.com>,
        "Raja Subramanian, Lakshmi Bai" 
        <lakshmi.bai.raja.subramanian@intel.com>,
        "Wan Mohamad, Wan Ahmad Zainie" 
        <wan.ahmad.zainie.wan.mohamad@intel.com>,
        Mark Gross <mgross@linux.intel.com>
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On Thu, Dec 3, 2020 at 8:10 AM Zulkifli, Muhammad Husaini
<muhammad.husaini.zulkifli@intel.com> wrote:

> >Yeah it has to be called from somewhere, if you want an abstraction to make
> >the driver neutral to any machine, then use a selector regulator. It can be
> >placed anywhere in the kernel as long as you can reference it.
>
> Sorry. I am not really aware of selector regulator. Can you point me to any references
> for this?

It is part of the regulator subsystem and the standard framework
there to handle regulators with an enumerable number of
specific voltage levels.

> IMHO, we do not need to overengineered it to add custom selector
> regulator just to suit this Keem Bay HW design.

That can be said about a lot of things we model with vqmmc.
Using standard abstractions makes things easier for maintainers.
We mostly design abstractions for maintenance not for the simplest way
to set bits in registers.

Yours,
Linus Walleij