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From:   Sven Van Asbroeck <thesven73@gmail.com>
Date:   Wed, 9 Dec 2020 12:36:40 -0500
Message-ID: <CAGngYiVKHoXPGxmScCnb-R6xoo9GNw5pG8V8Cpyk3meoJbskiw@mail.gmail.com>
Subject: Re: [PATCH] spi: dt-bindings: clarify CS behavior for spi-cs-high and
 gpio descriptors
To:     "H. Nikolaus Schaller" <hns@goldelico.com>
Cc:     Mark Brown <broonie@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        linux-spi <linux-spi@vger.kernel.org>,
        linux-gpio@vger.kernel.org,
        devicetree <devicetree@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Discussions about the Letux Kernel 
        <letux-kernel@openphoenux.org>, kernel@pyra-handheld.com,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Lukas Wunner <lukas@wunner.de>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Andreas Kemnade <andreas@kemnade.info>
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On Wed, Dec 9, 2020 at 4:57 AM H. Nikolaus Schaller <hns@goldelico.com> wrote:
>
> +
> +      device node     | cs-gpio       | CS pin state active | Note
> +      ================+===============+=====================+=====
> +      spi-cs-high     | -             | H                   |
> +      -               | -             | L                   |
> +      spi-cs-high     | ACTIVE_HIGH   | H                   |
> +      -               | ACTIVE_HIGH   | L                   | 1
> +      spi-cs-high     | ACTIVE_LOW    | H                   | 2
> +      -               | ACTIVE_LOW    | L                   |
> +

Doesn't this table simply say:
- specify   'spi-cs-high' for an active-high chip select
- leave out 'spi-cs-high' for an active-low  chip select
- the gpio active high/active low consumer flags are ignored
?

If so, then I would simply document it that way.
Simple is beautiful.