regulator: refcount fixes

Fix some refcounting issues in the regulator framework, supporting
regulator_disable() for regulators that were enabled at boot time
via machine constraints:

 - Update those regulators' usecounts after enabling, so they
   can cleanly be disabled at that level.

 - Remove the problematic per-consumer usecount, so there's
   only one level of enable/disable.

Buggy consumers could notice different bug symptoms.  The main
example would be refcounting bugs; also, any (out-of-tree) users
of the experimental regulator_set_optimum_mode() stuff which
don't call it when they're done using a regulator.

This is a net minor codeshrink.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
This commit is contained in:
David Brownell 2009-03-11 16:43:34 -08:00 committed by Liam Girdwood
parent 1dc60343f8
commit cd94b50530
1 changed files with 8 additions and 22 deletions

View File

@ -52,7 +52,6 @@ struct regulator {
int uA_load;
int min_uV;
int max_uV;
int enabled; /* count of client enables */
char *supply_name;
struct device_attribute dev_attr;
struct regulator_dev *rdev;
@ -815,6 +814,7 @@ static int set_machine_constraints(struct regulator_dev *rdev,
rdev->constraints = NULL;
goto out;
}
rdev->use_count = 1;
}
print_constraints(rdev);
@ -1068,10 +1068,6 @@ void regulator_put(struct regulator *regulator)
mutex_lock(&regulator_list_mutex);
rdev = regulator->rdev;
if (WARN(regulator->enabled, "Releasing supply %s while enabled\n",
regulator->supply_name))
_regulator_disable(rdev);
/* remove any sysfs entries */
if (regulator->dev) {
sysfs_remove_link(&rdev->dev.kobj, regulator->supply_name);
@ -1146,12 +1142,7 @@ int regulator_enable(struct regulator *regulator)
int ret = 0;
mutex_lock(&rdev->mutex);
if (regulator->enabled == 0)
ret = _regulator_enable(rdev);
else if (regulator->enabled < 0)
ret = -EIO;
if (ret == 0)
regulator->enabled++;
ret = _regulator_enable(rdev);
mutex_unlock(&rdev->mutex);
return ret;
}
@ -1162,6 +1153,11 @@ static int _regulator_disable(struct regulator_dev *rdev)
{
int ret = 0;
if (WARN(rdev->use_count <= 0,
"unbalanced disables for %s\n",
rdev->desc->name))
return -EIO;
/* are we the last user and permitted to disable ? */
if (rdev->use_count == 1 && !rdev->constraints->always_on) {
@ -1210,16 +1206,7 @@ int regulator_disable(struct regulator *regulator)
int ret = 0;
mutex_lock(&rdev->mutex);
if (regulator->enabled == 1) {
ret = _regulator_disable(rdev);
if (ret == 0)
regulator->uA_load = 0;
} else if (WARN(regulator->enabled <= 0,
"unbalanced disables for supply %s\n",
regulator->supply_name))
ret = -EIO;
if (ret == 0)
regulator->enabled--;
ret = _regulator_disable(rdev);
mutex_unlock(&rdev->mutex);
return ret;
}
@ -1266,7 +1253,6 @@ int regulator_force_disable(struct regulator *regulator)
int ret;
mutex_lock(&regulator->rdev->mutex);
regulator->enabled = 0;
regulator->uA_load = 0;
ret = _regulator_force_disable(regulator->rdev);
mutex_unlock(&regulator->rdev->mutex);