linux-kernel - Re: [PATCH] mtd: spi-nor: intel-spi: Do not try to make the SPI flash chip writable

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Message-ID: <CAFmMkTF9eVm0tpOKEy2rzdX=Scr3RwqHDFy_i24R3F5ok-4=eA@mail.gmail.com>
Date:   Tue, 4 Aug 2020 16:57:11 -0300
From:   Daniel Gutson <daniel@...ypsium.com>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Tudor Ambarus <tudor.ambarus@...rochip.com>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Richard Weinberger <richard@....at>,
        Vignesh Raghavendra <vigneshr@...com>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        Boris Brezillon <bbrezillon@...nel.org>,
        linux-mtd <linux-mtd@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Alex Bazhaniuk <alex@...ypsium.com>,
        Richard Hughes <hughsient@...il.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: Re: [PATCH] mtd: spi-nor: intel-spi: Do not try to make the SPI flash
 chip writable

On Tue, Aug 4, 2020 at 4:06 PM Arnd Bergmann <arnd@...db.de> wrote:
>
> On Tue, Aug 4, 2020 at 5:49 PM Daniel Gutson <daniel@...ypsium.com> wrote:
> > On Tue, Aug 4, 2020 at 12:21 PM Arnd Bergmann <arnd@...db.de> wrote:
> >>
> >> On Tue, Aug 4, 2020 at 3:58 PM Daniel Gutson
> >> <daniel.gutson@...ypsium.com> wrote:
> >> >
> >> > Context, the intel-spi has a module argument that controls
> >> > whether the driver attempts to turn the SPI flash chip writeable.
> >> > The default value is FALSE (don't try to make it writeable).
> >> > However, this flag applies only for a number of devices, coming from the
> >> > platform driver, whereas the devices detected through the PCI driver
> >> > (intel-spi-pci) are not subject to this check since the configuration
> >> > takes place in intel-spi-pci which doesn't have an argument.
> >>
> >> This is still factually incorrect, as explained at least three times
> >> now.
> >>
> >> Please either make the same change for both the Bay Trail
> >> platform driver and the PCI driver, or explain why you want them to
> >> be different rather than incorrectly claiming that you change them to
> >> be the same.
> >
> >
> > What about just saying
> >
> > "This patch removes the attempt by the intel-spi-pci driver to
> > make the chip always writable."
>
> Yes, that is much better, though it still sounds like it would at the
> moment allow writing to the device from software without also
> setting the module parameter. I would say something like
>
> "Disallow overriding the write protection in the PCI driver
> with a module parameter and instead honor the current
> state of the write protection as set by the firmware."

But wait, Mika, the author of the file, asked earlier not to remove
the module parameter of intel-spi,
and just remove the unconditional attempt to turn the chip writable in
intle-spi-pci.
So I'm not touching intel-pci, just removing that code from
intel-spi-pci without adding
a new module parameter.

Are you aligned on this?


>
> (note also: imperative form in the patch description rather than
> "this patch ...").
>
>       Arnd



-- 
Daniel Gutson
Argentina Site Director
Enginieering Director
Eclypsium

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