regulator: core: fix regulator_lock_supply regression
authorArnd Bergmann <arnd@arndb.de>
Fri, 27 Nov 2015 13:46:41 +0000 (14:46 +0100)
committerMark Brown <broonie@kernel.org>
Fri, 27 Nov 2015 16:37:04 +0000 (16:37 +0000)
commitbb41897e38c53458a88b271f2fbcd905ee1f9584
tree3f9cb105c24c182906db7fa0d6a287e5917a2f01
parentfa731ac7ea04a7d3a5c6d2f568132478c02a83b3
regulator: core: fix regulator_lock_supply regression

As noticed by Geert Uytterhoeven, my patch to avoid a harmless build warning
in regulator_lock_supply() was total crap and introduced a real bug:

> [ BUG: bad unlock balance detected! ]
> kworker/u4:0/6 is trying to release lock (&rdev->mutex) at:
> [<c0247b84>] regulator_set_voltage+0x38/0x50

we still lock the regulator supplies, but not the actual regulators,
so we are missing a lock, and the unlock is unbalanced.

This rectifies it by first locking the regulator device itself before
using the same loop as before to lock its supplies.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 716fec9d1965 ("[SUBMITTED] regulator: core: avoid unused variable warning")
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/regulator/core.c