From 606a25628187ce863b48d43ca42bc0cbe8342de9 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 16 Dec 2010 15:49:36 +0000 Subject: [PATCH] regulator: Add API to re-apply voltage to hardware When cooperating with an external control source the regulator setup may be changed underneath the API. Currently consumers can just redo the regulator_set_voltage() to restore a previously set configuration but provide an explicit API for doing this as optimsations in the regulator_set_voltage() implementation will shortly prevent that. Signed-off-by: Mark Brown Signed-off-by: Liam Girdwood --- drivers/regulator/core.c | 47 ++++++++++++++++++++++++++++++ include/linux/regulator/consumer.h | 1 + 2 files changed, 48 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 3d72cc8e2f3..a12cba32460 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1727,6 +1727,53 @@ out: } EXPORT_SYMBOL_GPL(regulator_set_voltage); +/** + * regulator_sync_voltage - re-apply last regulator output voltage + * @regulator: regulator source + * + * Re-apply the last configured voltage. This is intended to be used + * where some external control source the consumer is cooperating with + * has caused the configured voltage to change. + */ +int regulator_sync_voltage(struct regulator *regulator) +{ + struct regulator_dev *rdev = regulator->rdev; + int ret, min_uV, max_uV; + + mutex_lock(&rdev->mutex); + + if (!rdev->desc->ops->set_voltage && + !rdev->desc->ops->set_voltage_sel) { + ret = -EINVAL; + goto out; + } + + /* This is only going to work if we've had a voltage configured. */ + if (!regulator->min_uV && !regulator->max_uV) { + ret = -EINVAL; + goto out; + } + + min_uV = regulator->min_uV; + max_uV = regulator->max_uV; + + /* This should be a paranoia check... */ + ret = regulator_check_voltage(rdev, &min_uV, &max_uV); + if (ret < 0) + goto out; + + ret = regulator_check_consumers(rdev, &min_uV, &max_uV); + if (ret < 0) + goto out; + + ret = _regulator_do_set_voltage(rdev, min_uV, max_uV); + +out: + mutex_unlock(&rdev->mutex); + return ret; +} +EXPORT_SYMBOL_GPL(regulator_sync_voltage); + static int _regulator_get_voltage(struct regulator_dev *rdev) { int sel; diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h index ebd74726529..7954f6bd7ed 100644 --- a/include/linux/regulator/consumer.h +++ b/include/linux/regulator/consumer.h @@ -154,6 +154,7 @@ int regulator_is_supported_voltage(struct regulator *regulator, int min_uV, int max_uV); int regulator_set_voltage(struct regulator *regulator, int min_uV, int max_uV); int regulator_get_voltage(struct regulator *regulator); +int regulator_sync_voltage(struct regulator *regulator); int regulator_set_current_limit(struct regulator *regulator, int min_uA, int max_uA); int regulator_get_current_limit(struct regulator *regulator);