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Date:   Wed, 4 Jan 2023 16:05:02 +0000
From:   Lee Jones <lee@kernel.org>
To:     Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Linus Walleij <linus.walleij@linaro.org>,
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        Biju Das <biju.das@bp.renesas.com>,
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        <linux-renesas-soc@vger.kernel.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Jacopo Mondi <jacopo@jmondi.org>
Subject: Re: [PATCH v2 2/4] mfd: Add RZ/V2M PWC core driver
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> > > > If you do not have any resources to share, you can simply register
> > each
> > > > of the devices via Device Tree.  I do not see a valid reason to force
> > a
> > > > parent / child relationship for your use-case.
> > >
> > > There would probably be overlapping on the same memory region, which
> > would
> > > lead to ioremapping the same region multiple times, which is something
> > > I would prefer to avoid if possible.
> > 
> > Okay, so you *do* have shared resources.
> > 
> > In which case, why is simple-mfd not working for you?
> 
> The corresponding dt-bindings got rejected, unfortunately. I had to drop
> simple-mfd as a result of dropping the children of my simple-mfd DT node.

You have to write DT bindings to be OS agnostic.

They *must* match the H/W.  Little else matters.

How we interpret those in Linux is flexible however.

-- 
Lee Jones [李琼斯]