linux-kernel - Re: [PATCH] regulator: core: Fix enable GPIO reference counting

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Message-ID: <20150304112712.GI21293@sirena.org.uk>
Date:	Wed, 4 Mar 2015 11:27:12 +0000
From:	Mark Brown <broonie@...nel.org>
To:	Doug Anderson <dianders@...omium.org>
Cc:	milo.kim@...com, Axel Lin <axel.lin@...ics.com>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Olof Johansson <olof@...om.net>,
	Javier Martinez Canillas <javier.martinez@...labora.co.uk>,
	Paul Stewart <pstew@...omium.org>,
	"stable@...r.kernel.org" <stable@...r.kernel.org>,
	Liam Girdwood <lgirdwood@...il.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] regulator: core: Fix enable GPIO reference counting

On Tue, Mar 03, 2015 at 03:21:21PM -0800, Doug Anderson wrote:

> It looks as if "ena_gpio_state" is not quite what I thought it was and
> I think is not actually consistent in the regulator framework itself.
> In _regulator_do_enable() and _regulator_do_disable() is clear that
> ena_gpio_state is 1 when an "rdev" is enabled and 0 when the "rdev" is
> disabled.  That was my assumption.  It's also clear in
> _regulator_is_enabled().

> ...but then I looked in regulator_register().  There you can see that
> ena_gpio_state could be set to 1 if you've got an active low GPIO that
> is disabled at boot.  That totally throws my logic for a loop.  Also
> with my patch the reference counting will be all messed up for active
> high / boot on regulators.  :(

Isn't that just a bug in the registration code?  I'd not be entirely
surprised if that were the case.

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