From 70cfef26267474f94ff4a988fb45ff78442b1cf4 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 29 Jun 2015 09:04:43 +0900 Subject: [PATCH] regulator: Add lockdep asserts to help detecting locking misuse Add lockdep_assert_held_once() to functions explicitly mentioning that rdev or regulator_list mutex must be held. Using WARN_ONCE shouldn't pollute the dmesg to much. The patch (if CONFIG_LOCKDEP enabled) will show warnings in certain regulators calling regulator_notifier_call_chain() without rdev->mutex held. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Mark Brown --- drivers/regulator/core.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index c9f72019bd68..68b616580533 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -640,6 +640,8 @@ static int drms_uA_update(struct regulator_dev *rdev) int current_uA = 0, output_uV, input_uV, err; unsigned int mode; + lockdep_assert_held_once(&rdev->mutex); + /* * first check to see if we can set modes at all, otherwise just * tell the consumer everything is OK. @@ -760,6 +762,8 @@ static int suspend_set_state(struct regulator_dev *rdev, /* locks held by caller */ static int suspend_prepare(struct regulator_dev *rdev, suspend_state_t state) { + lockdep_assert_held_once(&rdev->mutex); + if (!rdev->constraints) return -EINVAL; @@ -1587,6 +1591,8 @@ static void _regulator_put(struct regulator *regulator) if (regulator == NULL || IS_ERR(regulator)) return; + lockdep_assert_held_once(®ulator_list_mutex); + rdev = regulator->rdev; debugfs_remove_recursive(regulator->debugfs); @@ -1965,6 +1971,8 @@ static int _regulator_enable(struct regulator_dev *rdev) { int ret; + lockdep_assert_held_once(&rdev->mutex); + /* check voltage and requested load before enabling */ if (rdev->constraints && (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_DRMS)) @@ -2065,6 +2073,8 @@ static int _regulator_disable(struct regulator_dev *rdev) { int ret = 0; + lockdep_assert_held_once(&rdev->mutex); + if (WARN(rdev->use_count <= 0, "unbalanced disables for %s\n", rdev_get_name(rdev))) return -EIO; @@ -2143,6 +2153,8 @@ static int _regulator_force_disable(struct regulator_dev *rdev) { int ret = 0; + lockdep_assert_held_once(&rdev->mutex); + ret = _notifier_call_chain(rdev, REGULATOR_EVENT_FORCE_DISABLE | REGULATOR_EVENT_PRE_DISABLE, NULL); if (ret & NOTIFY_STOP_MASK) @@ -3439,6 +3451,8 @@ EXPORT_SYMBOL_GPL(regulator_bulk_free); int regulator_notifier_call_chain(struct regulator_dev *rdev, unsigned long event, void *data) { + lockdep_assert_held_once(&rdev->mutex); + _notifier_call_chain(rdev, event, data); return NOTIFY_DONE; -- 2.20.1