[PATCH v2 01/14] regulator: core: Add regulator_sync_voltage_rdev()

Dmitry Osipenko
2021-05-23T23:13:55Z

Some NVIDIA Tegra devices use a CPU soft-reset method for the reboot and
in this case we need to restore the coupled voltages to the state that is
suitable for hardware during boot. Add new regulator_sync_voltage_rdev()
helper which is needed by regulator drivers in order to sync voltage of
a coupled regulators.

Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/regulator/core.c | 23 +++++++++++++++++++++++
include/linux/regulator/driver.h | 1 +
2 files changed, 24 insertions(+)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index e20e77e4c159..aae978c0c148 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -4111,6 +4111,29 @@ int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
}
EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel);

+int regulator_sync_voltage_rdev(struct regulator_dev *rdev)
+{
+ int ret;
+
+ regulator_lock(rdev);
+
+ if (!rdev->desc->ops->set_voltage &&
+ !rdev->desc->ops->set_voltage_sel) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* balance only, if regulator is coupled */
+ if (rdev->coupling_desc.n_coupled > 1)
+ ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON);
+ else
+ ret = -EOPNOTSUPP;
+
+out:
+ regulator_unlock(rdev);
+ return ret;
+}
+
/**
* regulator_sync_voltage - re-apply last regulator output voltage
* @regulator: regulator source
diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index 4ea520c248e9..35e5a611db81 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -540,6 +540,7 @@ int regulator_set_current_limit_regmap(struct regulator_dev *rdev,
int regulator_get_current_limit_regmap(struct regulator_dev *rdev);
void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data);
int regulator_set_ramp_delay_regmap(struct regulator_dev *rdev, int ramp_delay);
+int regulator_sync_voltage_rdev(struct regulator_dev *rdev);

/*
* Helper functions intended to be used by regulator drivers prior registering
--
2.30.2