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References: <20201203011649.1405292-1-swboyd@chromium.org> <20201203011649.1405292-2-swboyd@chromium.org>
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From:   Doug Anderson <dianders@chromium.org>
Date:   Wed, 2 Dec 2020 17:17:51 -0800
Message-ID: <CAD=FV=WpLAsb3akm2m7i_azj_3etxR0Y+L-wu9BC8YdN-C7KOg@mail.gmail.com>
Subject: Re: [PATCH 1/2] platform/chrome: cros_ec_spi: Don't overwrite spi::mode
To:     Stephen Boyd <swboyd@chromium.org>
Cc:     Benson Leung <bleung@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Simon Glass <sjg@chromium.org>,
        Gwendal Grignou <gwendal@chromium.org>,
        Alexandru M Stan <amstan@chromium.org>
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Hi,

On Wed, Dec 2, 2020 at 5:16 PM Stephen Boyd <swboyd@chromium.org> wrote:
>
> There isn't any need to overwrite the mode here in the driver with what
> has been detected by the firmware, such as DT or ACPI. In fact, if we
> use the SPI CS gpio descriptor feature we will overwrite the mode with
> SPI_MODE_0 where it already contains SPI_MODE_0 and more importantly
> SPI_CS_HIGH. Clearing the SPI_CS_HIGH bit causes the CS line to toggle
> when the device is probed when it shouldn't change, confusing the driver
> and making it fail to probe. Drop the assignment and let the spi core
> take care of it.
>
> Fixes: a17d94f0b6e1 ("mfd: Add ChromeOS EC SPI driver")
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Gwendal Grignou <gwendal@chromium.org>
> Cc: Douglas Anderson <dianders@chromium.org>
> Cc: Alexandru M Stan <amstan@chromium.org>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> ---
>  drivers/platform/chrome/cros_ec_spi.c | 1 -

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>