linux-kernel - Re: [PATCH v2] regulator: wm8994: Don't use devres for enable GPIOs

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Message-ID: <CACRpkdb9KStEkMigDX2kA4Q-tr6DuuWqqTuF6jXZK67Zp+DxmA@mail.gmail.com>
Date:   Thu, 22 Nov 2018 16:47:20 +0100
From:   Linus Walleij <linus.walleij@...aro.org>
To:     Charles Keepax <ckeepax@...nsource.cirrus.com>
Cc:     Mark Brown <broonie@...nel.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 v2] regulator: wm8994: Don't use devres for enable GPIOs

On Thu, Nov 22, 2018 at 3:19 PM Linus Walleij <linus.walleij@...aro.org> wrote:
> On Wed, Nov 21, 2018 at 11:13 AM Charles Keepax
> <ckeepax@...nsource.cirrus.com> wrote:
>
> > The regulator core takes over managing the lifetime of the enable GPIO
> > once the regulator is registered. As such we shouldn't register the
> > enable GPIO using devm, or it will be freed twice.
> >
> > Reported-by: Marek Szyprowski <m.szyprowski@...sung.com>
> > Signed-off-by: Charles Keepax <ckeepax@...nsource.cirrus.com>
>
> Reviewed-by: Linus Walleij <linus.walleij@...aro.org>

Oh no this is not the right solution I think.

All drivers passing a descriptor (config->ena_gpiod) do their
own refcounting, including some using a function that has no
non-devm* counterpart.

It is better if we teach the core to not gpiod_put() those.

The other patch series I am floating to get rid of the legacy
GPIO handling from the core will do away with all the
legacy GPIO handling anyway, so let me introduce a bit
of ugliness (that can be backported) and then delete that
ugliness with an updated series v8 of my legacy GPIO
cleanup.

Sorry for the inconvenience.

Will send a patch soon.

Yours,
Linus Walleij