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References: <20201110142032.24071-1-TheSven73@gmail.com>
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From:   Sven Van Asbroeck <thesven73@gmail.com>
Date:   Wed, 11 Nov 2020 11:03:37 -0500
Message-ID: <CAGngYiVftXwcYbeSgXtiu9aMUG6GQTAcON=CK32o5=YLM40g4A@mail.gmail.com>
Subject: Re: [PATCH net v2] net: phy: spi_ks8995: Do not overwrite SPI mode flags
To:     Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Jakub Kicinski <kuba@kernel.org>
Cc:     Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        netdev <netdev@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Mark Brown <broonie@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
        Frederic LAMBERT <frdrc66@gmail.com>,
        Gabor Juhos <juhosg@openwrt.org>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        linux-spi <linux-spi@vger.kernel.org>
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A spi core fix has been accepted which makes this patch unnecessary.

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git/commit/?id=766c6b63aa044e84b045803b40b14754d69a2a1d

On Tue, Nov 10, 2020 at 9:20 AM Sven Van Asbroeck <thesven73@gmail.com> wrote:
>
>
> This driver makes sure the underlying SPI bus is set to "mode 0"
> by assigning SPI_MODE_0 to spi->mode. Which overwrites all other
> SPI mode flags.
>
> In some circumstances, this can break the underlying SPI bus driver.
> For example, if SPI_CS_HIGH is set on the SPI bus, the driver
> will clear that flag, which results in a chip-select polarity issue.
>
> Fix by changing only the SPI_MODE_N bits, i.e. SPI_CPHA and SPI_CPOL.
>
> Fixes: a8e510f682fe ("phy: Micrel KS8995MA 5-ports 10/100 managed Ethernet switch support added")
> Fixes: f3186dd87669 ("spi: Optionally use GPIO descriptors for CS GPIOs")
> Link: https://patchwork.kernel.org/project/spi-devel-general/patch/20201106150706.29089-1-TheSven73@gmail.com/#23747737
> Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com>
> ---