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From:   Daniel Gutson <daniel@eclypsium.com>
Date:   Mon, 3 Aug 2020 10:17:59 -0300
Message-ID: <CAFmMkTH8TpezraD2d3_rpaPt+hoO3gpJrRPs56-aGHupm6iNtQ@mail.gmail.com>
Subject: Re: [PATCH] Module argument to control whether intel-spi-pci attempts
 to turn the SPI flash chip writeable
To:     Mika Westerberg <mika.westerberg@linux.intel.com>
Cc:     Richard Hughes <hughsient@gmail.com>,
        Tudor Ambarus <tudor.ambarus@microchip.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Boris Brezillon <bbrezillon@kernel.org>,
        linux-mtd <linux-mtd@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Alex Bazhaniuk <alex@eclypsium.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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On Mon, Aug 3, 2020 at 10:06 AM Mika Westerberg
<mika.westerberg@linux.intel.com> wrote:
>
> On Mon, Aug 03, 2020 at 09:58:23AM -0300, Daniel Gutson wrote:
> > On Mon, Aug 3, 2020 at 7:27 AM Mika Westerberg
> > <mika.westerberg@linux.intel.com> wrote:
> > >
> > > On Mon, Aug 03, 2020 at 11:18:12AM +0100, Richard Hughes wrote:
> > > > On Mon, 3 Aug 2020 at 10:57, Mika Westerberg
> > > > <mika.westerberg@linux.intel.com> wrote:
> > > > > I think instead of this we should simply make it so that the driver
> > > > > never tries to make the chip writable.
> > > >
> > > > I think this is a good idea, but I wasn't sure if it was an acceptable
> > > > behaviour change. Should the driver still try to set BCR_WPD when
> > > > writing an image (i.e. defer the setting of write enable until later),
> > > > or just not set the BCR register at all? I think your last comment was
> > > > the latter, but wanted to check.
> > >
> > > I would say not set it at all. I think it was (my) mistake to set it in
> > > the first place.
> >
> > Do you want me to remove the module parameter from intel-spi too and
> > do the same?
>
> No, I think that should still be left there. Then by default it is
> read-only and you can only enable writing if the BIOS allows it and that
> the user actually requested it.

OK. Patch heading your way in 1h.


-- 
Daniel Gutson
Argentina Site Director
Enginieering Director
Eclypsium

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