linux-kernel - "regulator: Enable supply regulator if child rail is enabled" broken?

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Message-ID: <CAH+eYFAJ0FSiZoDiyYJsEg1j-cAhG7DkCwFNJGe5vBNpiUM7ug@mail.gmail.com>
Date:	Tue, 14 Aug 2012 10:38:42 +0200
From:	Rabin Vincent <rabin@....in>
To:	ldewangan@...dia.com,
	Mark Brown <broonie@...nsource.wolfsonmicro.com>, lrg@...com
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: "regulator: Enable supply regulator if child rail is enabled" broken?

It appears that this patch causes incorrect reference counting on supply
regulators if the child regulator is enabled with for example boot_on=true:

commit b2296bd43e781976743354c668a356b0df98e1da
Author: Laxman Dewangan <ldewangan@...dia.com>
Date:   Mon Jan 2 13:08:45 2012 +0530

    regulator: Enable supply regulator if child rail is enabled.

If a regulator is enabled at boot (by constraints), then this patch calls
regulator_enable() on the supply regulator, leading to a use_count increase on
the supply.  However, this patch adds no code to perform the corresponding
regulator_disable(), leaving the supply regulator on even when all consumers
have disabled it.

AFAICS, this patch would have only worked for always_on regulators.
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