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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Thu, 25 May 2023 12:13:11 +0300
Message-ID: <CAHp75VfVr0N4Fv=s_12vcTi8=pGWJgeWoXpxQvqSNWDcZauS=A@mail.gmail.com>
Subject: Re: using libgpiod to replace sysfs ABI (was Re: [PATCH] gpiolib:
 Avoid side effects in gpio_is_visible())
To:     Chris Packham <Chris.Packham@alliedtelesis.co.nz>
Cc:     Kent Gibson <warthog618@gmail.com>,
        "linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Thu, May 25, 2023 at 2:53=E2=80=AFAM Chris Packham
<Chris.Packham@alliedtelesis.co.nz> wrote:
> On 24/05/23 17:41, Kent Gibson wrote:

...

> It'd also be great if there was some way of ensuring that a line's state
> is kept after the application has released the request (i.e. the txdis
> case I mentioned). But that probably needs work on the kernel side to
> make such guarantees.

Won't happen. It will require too much of strictness to be added into
the kernel with likely breakage of the existing code and
documentation. What is being discussed is a D-Bus (like?) daemon +
Policy in user space that will allow user / process / cgroup / etc to
"own" the line and track its state.

--=20
With Best Regards,
Andy Shevchenko