From bca7bbfff37808d56355bbcf0ceec34f0cc6c85d Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Wed, 9 May 2012 21:38:33 +0100 Subject: regulator: core: Allow drivers to set simple linear voltage maps as data A lot of regulator hardware maps selectors on to voltages with a simple linear mapping function selector = base + (selector * step size) Provide off the shelf list_voltage() and map_voltage() operations which use new min_uV and uV_step members in the regulator_desc to implement this function. Signed-off-by: Mark Brown Acked-by: Liam Girdwood --- drivers/regulator/core.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) (limited to 'drivers/regulator') diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 5e32698d893..5751f5ed47c 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1859,6 +1859,26 @@ int regulator_count_voltages(struct regulator *regulator) } EXPORT_SYMBOL_GPL(regulator_count_voltages); +/** + * regulator_list_voltage_linear - List voltages with simple calculation + * + * @rdev: Regulator device + * @selector: Selector to convert into a voltage + * + * Regulators with a simple linear mapping between voltages and + * selectors can set min_uV and uV_step in the regulator descriptor + * and then use this function as their list_voltage() operation, + */ +int regulator_list_voltage_linear(struct regulator_dev *rdev, + unsigned int selector) +{ + if (selector >= rdev->desc->n_voltages) + return -EINVAL; + + return rdev->desc->min_uV + (rdev->desc->uV_step * selector); +} +EXPORT_SYMBOL_GPL(regulator_list_voltage_linear); + /** * regulator_list_voltage - enumerate supported voltages * @regulator: regulator source @@ -2007,6 +2027,39 @@ int regulator_map_voltage_iterate(struct regulator_dev *rdev, } EXPORT_SYMBOL_GPL(regulator_map_voltage_iterate); +/** + * regulator_map_voltage_linear - map_voltage() for simple linear mappings + * + * @rdev: Regulator to operate on + * @min_uV: Lower bound for voltage + * @max_uV: Upper bound for voltage + * + * Drivers providing min_uV and uV_step in their regulator_desc can + * use this as their map_voltage() operation. + */ +int regulator_map_voltage_linear(struct regulator_dev *rdev, + int min_uV, int max_uV) +{ + int ret, voltage; + + if (!rdev->desc->uV_step) { + BUG_ON(!rdev->desc->uV_step); + return -EINVAL; + } + + ret = (min_uV - rdev->desc->min_uV) / rdev->desc->uV_step; + if (ret < 0) + return ret; + + /* Map back into a voltage to verify we're still in bounds */ + voltage = rdev->desc->ops->list_voltage(rdev, ret); + if (voltage < min_uV || voltage > max_uV) + return -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(regulator_map_voltage_linear); + static int _regulator_do_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV) { -- cgit v1.2.3-70-g09d2