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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Mon, 3 Aug 2020 15:54:55 +0200
Message-ID: <CAK8P3a0rZi9hBsA6+YQCpCdYj6uY6z+cfVVi37jY1aNx7B5iTQ@mail.gmail.com>
Subject: Re: [PATCH] Remove attempt by intel-spi-pci to turn the SPI flash
 chip writeable
To:     Daniel Gutson <daniel.gutson@eclypsium.com>
Cc:     Tudor Ambarus <tudor.ambarus@microchip.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Mika Westerberg <mika.westerberg@linux.intel.com>,
        Boris Brezillon <bbrezillon@kernel.org>,
        linux-mtd <linux-mtd@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Alex Bazhaniuk <alex@eclypsium.com>,
        Richard Hughes <hughsient@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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On Mon, Aug 3, 2020 at 3:45 PM Daniel Gutson
<daniel.gutson@eclypsium.com> wrote:

> 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 part of the description sounds wrong: the current behavior is that
the BIOS setting is ignored for PCI devices and it only uses the module
parameter, the same way as it does for the platform driver.

With your patch, both the BIOS setting and the module parameter
have to explicitly allow writing on PCI devices, while at least for Bay
Trail platform devices the BIOS write protection is still ignored.

It sounds like this is what you want, but you should update the description
accordingly.

      Arnd