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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Fri, 11 Sep 2020 08:28:45 +0200
Message-ID: <CAMuHMdU9vEUasHMeS=OiHX+16dgQGPdmjEtCi+-YLcXvw4BM7g@mail.gmail.com>
Subject: Re: [PATCH] ide/macide: Convert Mac IDE driver to platform driver
To:     Finn Thain <fthain@telegraphics.com.au>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Joshua Thompson <funaho@jurai.org>,
        linux-m68k <linux-m68k@lists.linux-m68k.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-ide@vger.kernel.org
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Hi Finn,

On Fri, Sep 11, 2020 at 1:05 AM Finn Thain <fthain@telegraphics.com.au> wrote:
> On Thu, 10 Sep 2020, Geert Uytterhoeven wrote:
> > On Thu, Sep 10, 2020 at 2:23 AM Finn Thain <fthain@telegraphics.com.au> wrote:
> > > > How does the driver know not to use the special port_ops after
> > > > this change?
> > > >
> > >
> > > The driver always uses the special port_ops after this change because it
> > > no longer handles the MAC_IDE_BABOON case. That case is handled by either
> >
> > non-MAC_IDE_BABOON case?
> >
> > > drivers/ata/pata_platform.c or drivers/ide/ide_platform.c, depending on
> > > .config.
> >
> > Ideally, we do need to differentiate, right?
> >
>
> Sorry, I'm lost.
>
> The commit log explains that the macide driver is only intended to support
> two of the three variants, because the generic drivers are already able to
> support the third variant (Baboon). Stan confirmed this on his PB 190.
>
> But, IIUC, you seem to want macide to continue to support all three
> variants (?) The existing code to implement that has an old bug that
> reassigns d.port_ops when it is const. IMO, the const is correct because
> macide should concern itself with mac hardware quirks and should not try
> to mimic a generic driver by setting d.port_ops = NULL. Does that make
> sense?

Sorry, I completely missed that the Baboon case registers a "pata_platform"
device instead of a "macide" device.  Hence please ignore my comments
related to that.  Sorry for the noise.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds