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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Wed, 14 Sep 2022 16:20:12 +0100
Message-ID: <CAMuHMdV7__tOo1waXCg7ayKG9XLxKWZfqZX56vXPH6oPEmPj9g@mail.gmail.com>
Subject: Re: [PATCH] gpiolib: TODO: add an item about GPIO safe-state
To:     Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     Kent Gibson <warthog618@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Drew Fustini <dfustini@baylibre.com>,
        Marek Vasut <marek.vasut@gmail.com>,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org
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Hi Bartosz,

On Wed, Sep 14, 2022 at 4:11 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> This adds a new TODO item for gpiolib and can also be used to start
> a discussion about the need for it and implementation details.
>
> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

> --- a/drivers/gpio/TODO
> +++ b/drivers/gpio/TODO

> +This item is about proposing a solution, most likely in the form of a new device
> +property called "safe-state" that would define the safe states of specific lines
> +(e.g. output-high) but not block the line from being requested by users who
> +could then modify that default state. Once released the GPIO core would then
> +put the line back into the "safe-state".

#bikeshedding

If this state is the "safe" state, would that imply that any other state is
"unsafe"? I guess not, as the idea is that a knowledgeable driver can
still change it (else a hog would be sufficient).
Hence I think "idle-state" would reflect this better. Any other thoughts?

Thanks!

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