Re: [PATCH] pinctrl: sunxi: set pin function as input on export

From	Linus Walleij <linus.walleij@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] pinctrl: sunxi: set pin function as input on export
Date	2016-02-15 23:10 +0100
Message-ID	<r2zvb-794-1@gated-at.bofh.it> (permalink)
References	<qZV8S-6zW-33@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Mon, Feb 8, 2016 at 3:37 PM, Krzysztof Adamski
<krzysztof.adamski@tieto.com> wrote:

> Default function of a pin in sunxi SoCs is "disabled". By default gpios
> exported by sysfs are set as input and indeed, when reading "direction"
> file you will get "in". The "value" pin won't return proper value,
> though, confusing user of this interface.
>
> This patch sets direction of a GPIO as input when exporting it.
>
> Signed-off-by: Krzysztof Adamski <krzysztof.adamski@tieto.com>

As maxime says it's not a sunxi problem.

So maybe it is wrong to set pins to either input or output when
exporting them, I suspect they should be exported as is.

Also: the sysfs ABI is deprecated. I suggest you invest your time
in working on the new chardev ABI.

Yours,
Linus Walleij

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Re: [PATCH] pinctrl: sunxi: set pin function as input on export Linus Walleij <linus.walleij@linaro.org> - 2016-02-15 23:10 +0100
  Re: [PATCH] pinctrl: sunxi: set pin function as input on export Krzysztof Adamski <krzysztof.adamski@tieto.com> - 2016-02-16 09:10 +0100
    Re: [PATCH] pinctrl: sunxi: set pin function as input on export Linus Walleij <linus.walleij@linaro.org> - 2016-02-16 16:40 +0100

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