linux-kernel - Re: [PATCH 3/3] gpio: Add reference counting for non-exclusive GPIOs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20181126140927.GD9715@sirena.org.uk>
Date:   Mon, 26 Nov 2018 14:09:27 +0000
From:   Mark Brown <broonie@...nel.org>
To:     Charles Keepax <ckeepax@...nsource.cirrus.com>
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        Liam Girdwood <lgirdwood@...il.com>,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        patches@...nsource.cirrus.com
Subject: Re: [PATCH 3/3] gpio: Add reference counting for non-exclusive GPIOs

On Mon, Nov 26, 2018 at 01:00:01PM +0000, Charles Keepax wrote:
> On Fri, Nov 23, 2018 at 01:25:22PM +0000, Mark Brown wrote:

> > help the multiple users find each other somehow.  I think what we want
> > to do here is either push the gpiod requests into the regulator core or
> > change things so that once the regulator is registered with the
> > regulator core the regulator core owns and is responsible for freeing
> > the regulator.

> On the co-ordinating do we expect that the behaviour will
> be that the GPIO should in the "enabled" state whenever any
> regulator is requesting it? IE. the GPIO state is an OR of
> the regulator states. Or are we expecting to handle more
> complex interaction?

For the regulators that's what we do, yes - it's like they're all
sharing a single regulator.  That probably won't be true in general for
all GPIO users.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)