regulator: core: Fix enable_count imbalance with EXCLUSIVE_GET
authorZev Weiss <zev@bewilderbeest.net>
Thu, 5 May 2022 04:31:52 +0000 (21:31 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Jun 2022 08:22:54 +0000 (10:22 +0200)
commit81180f6d74c28ae91c3179715aa98e26fbde1c13
tree482d5cf5d15949a90cce5949b6b422733ecf57af
parent75868ee93b1daf78e738544b2fc944aaca11fe81
regulator: core: Fix enable_count imbalance with EXCLUSIVE_GET

[ Upstream commit c3e3ca05dae37f8f74bb80358efd540911cbc2c8 ]

Since the introduction of regulator->enable_count, a driver that did
an exclusive get on an already-enabled regulator would end up with
enable_count initialized to 0 but rdev->use_count initialized to 1.
With that starting point the regulator is effectively stuck enabled,
because if the driver attempted to disable it it would fail the
enable_count underflow check in _regulator_handle_consumer_disable().

The EXCLUSIVE_GET path in _regulator_get() now initializes
enable_count along with rdev->use_count so that the regulator can be
disabled without underflowing the former.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Fixes: 5451781dadf85 ("regulator: core: Only count load for enabled consumers")
Link: https://lore.kernel.org/r/20220505043152.12933-1-zev@bewilderbeest.net
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/regulator/core.c