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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Tue, 6 Aug 2019 10:09:17 +0200
Message-ID: <CAMuHMdXp9GAgWE7Ea_oA08PdPc8+J_wGVhM7L5B466OSbr7D_A@mail.gmail.com>
Subject: Re: [PATCH v3 1/4] serial: mctrl_gpio: Avoid probe failures in case
 of missing gpiolib
To:     Schrempf Frieder <frieder.schrempf@kontron.de>
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        "shawnguo@kernel.org" <shawnguo@kernel.org>,
        "s.hauer@pengutronix.de" <s.hauer@pengutronix.de>,
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        "festevam@gmail.com" <festevam@gmail.com>,
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        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        <linux-arm-kernel@lists.infradead.org>,
        "geert+renesas@glider.be" <geert+renesas@glider.be>,
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On Fri, Aug 2, 2019 at 12:04 PM Schrempf Frieder
<frieder.schrempf@kontron.de> wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
>
> If CONFIG_GPIOLIB is not enabled, mctrl_gpio_init() and
> mctrl_gpio_init_noauto() will currently return an error pointer with
> -ENOSYS. As the mctrl GPIOs are usually optional, drivers need to
> check for this condition to allow continue probing.
>
> To avoid the need for this check in each driver, we return NULL
> instead, as all the mctrl_gpio_*() functions are skipped anyway.
> We also adapt mctrl_gpio_to_gpiod() to be in line with this change.
>
> Reviewed-by: Fabio Estevam <festevam@gmail.com>
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds