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Date:   Wed, 6 Mar 2019 09:27:59 +0000
From:   Charles Keepax <ckeepax@opensource.cirrus.com>
To:     Steve Twiss <stwiss.opensource@diasemi.com>
CC:     Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Support Opensource <support.opensource@diasemi.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Cirrus Patches <patches@opensource.cirrus.com>
Subject: Re: [PATCH 11/13] regulator: wm831x: Fix notifier mutex lock warning
Message-ID: <20190306092759.GG46536@ediswmail.ad.cirrus.com>
References: <cover.1551808797.git.stwiss.opensource@diasemi.com>
 <08948a3fe926ba9fbae124fa972df766820d3289.1551808797.git.stwiss.opensource@diasemi.com>
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On Tue, Feb 26, 2019 at 03:48:46PM +0000, Steve Twiss wrote:
> The mutex for the regulator_dev must be controlled by the caller of
> the regulator_notifier_call_chain(), as described in the comment
> for that function.
> 
> Failure to mutex lock and unlock surrounding the notifier call results
> in a kernel WARN_ON_ONCE() which will dump a backtrace for the
> regulator_notifier_call_chain() when that function call is first made.
> The mutex can be controlled using the regulator_lock/unlock() API.
> 
> Fixes: e4ee831f949a ("regulator: Add WM831x DC-DC buck convertor support")
> Suggested-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
> Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
> ---

Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>

Thanks,
Charles