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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Wed, 13 Sep 2023 14:24:27 +0200
Message-ID: <CACRpkdax-CrB42LeQ1bs3E7VqMncsgEwMs7b_v7J6R5AE+BjAg@mail.gmail.com>
Subject: Re: [PATCH 3/5] mmc: slot-gpio: use gpiod_set_active_[low|high]()
To:     Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     Andy Shevchenko <andy@kernel.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Paul Cercueil <paul@crapouillou.net>,
        Harvey Hunt <harveyhuntnexus@gmail.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Daniel Scally <djrscally@gmail.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Mark Gross <markgross@kernel.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mmc@vger.kernel.org, linux-mips@vger.kernel.org,
        linux-mtd@lists.infradead.org, platform-driver-x86@vger.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
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On Wed, Sep 13, 2023 at 1:50=E2=80=AFPM Bartosz Golaszewski <brgl@bgdev.pl>=
 wrote:

> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> We have new, less cumbersome and clearer interfaces for controlling GPIO
> polarity. Use them in the MMC code.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

I like the looks of the code better, obviously but this looks like this for
a reason unfortunately.

See the following from
Documentation/devicetree/bindings/mmc/mmc-controller.yaml:

  # CD and WP lines can be implemented on the hardware in one of two
  # ways: as GPIOs, specified in cd-gpios and wp-gpios properties, or
  # as dedicated pins. Polarity of dedicated pins can be specified,
  # using *-inverted properties. GPIO polarity can also be specified
  # using the GPIO_ACTIVE_LOW flag. This creates an ambiguity in the
  # latter case. We choose to use the XOR logic for GPIO CD and WP
  # lines.  This means, the two properties are "superimposed," for
  # example leaving the GPIO_ACTIVE_LOW flag clear and specifying the
  # respective *-inverted property property results in a
  # double-inversion and actually means the "normal" line polarity is
  # in effect.

Will you still provide the desired "double inversion" after this patch?

Yours,
Linus Walleij