diff options
Diffstat (limited to 'drivers/regulator/helpers.c')
| -rw-r--r-- | drivers/regulator/helpers.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c index f22d21b35d..c4877cecf7 100644 --- a/drivers/regulator/helpers.c +++ b/drivers/regulator/helpers.c @@ -184,3 +184,189 @@ int regulator_list_voltage_linear(struct regulator_dev *rdev, return rdev->desc->min_uV + (rdev->desc->uV_step * selector); } EXPORT_SYMBOL_GPL(regulator_list_voltage_linear); + +/** + * regulator_desc_list_voltage_linear_range - List voltages for linear ranges + * + * @desc: Regulator desc for regulator which volatges are to be listed + * @selector: Selector to convert into a voltage + * + * Regulators with a series of simple linear mappings between voltages + * and selectors who have set linear_ranges in the regulator descriptor + * can use this function prior regulator registration to list voltages. + * This is useful when voltages need to be listed during device-tree + * parsing. + */ +int regulator_desc_list_voltage_linear_range(const struct regulator_desc *desc, + unsigned int selector) +{ + const struct regulator_linear_range *range; + int i; + + if (!desc->n_linear_ranges) { + BUG_ON(!desc->n_linear_ranges); + return -EINVAL; + } + + for (i = 0; i < desc->n_linear_ranges; i++) { + range = &desc->linear_ranges[i]; + + if (!(selector >= range->min_sel && + selector <= range->max_sel)) + continue; + + selector -= range->min_sel; + + return range->min_uV + (range->uV_step * selector); + } + + return -EINVAL; +} +EXPORT_SYMBOL_GPL(regulator_desc_list_voltage_linear_range); + +/** + * regulator_list_voltage_linear_range - List voltages for linear ranges + * + * @rdev: Regulator device + * @selector: Selector to convert into a voltage + * + * Regulators with a series of simple linear mappings between voltages + * and selectors can set linear_ranges in the regulator descriptor and + * then use this function as their list_voltage() operation, + */ +int regulator_list_voltage_linear_range(struct regulator_dev *rdev, + unsigned int selector) +{ + return regulator_desc_list_voltage_linear_range(rdev->desc, selector); +} +EXPORT_SYMBOL_GPL(regulator_list_voltage_linear_range); + +/** + * regulator_map_voltage_linear_range - map_voltage() for multiple linear ranges + * + * @rdev: Regulator to operate on + * @min_uV: Lower bound for voltage + * @max_uV: Upper bound for voltage + * + * Drivers providing linear_ranges in their descriptor can use this as + * their map_voltage() callback. + */ +int regulator_map_voltage_linear_range(struct regulator_dev *rdev, + int min_uV, int max_uV) +{ + const struct regulator_linear_range *range; + int ret = -EINVAL; + int voltage, i; + + if (!rdev->desc->n_linear_ranges) { + BUG_ON(!rdev->desc->n_linear_ranges); + return -EINVAL; + } + + for (i = 0; i < rdev->desc->n_linear_ranges; i++) { + int linear_max_uV; + + range = &rdev->desc->linear_ranges[i]; + linear_max_uV = range->min_uV + + (range->max_sel - range->min_sel) * range->uV_step; + + if (!(min_uV <= linear_max_uV && max_uV >= range->min_uV)) + continue; + + if (min_uV <= range->min_uV) + min_uV = range->min_uV; + + /* range->uV_step == 0 means fixed voltage range */ + if (range->uV_step == 0) { + ret = 0; + } else { + ret = DIV_ROUND_UP(min_uV - range->min_uV, + range->uV_step); + if (ret < 0) + return ret; + } + + ret += range->min_sel; + + /* + * Map back into a voltage to verify we're still in bounds. + * If we are not, then continue checking rest of the ranges. + */ + voltage = rdev->desc->ops->list_voltage(rdev, ret); + if (voltage >= min_uV && voltage <= max_uV) + break; + } + + if (i == rdev->desc->n_linear_ranges) + return -EINVAL; + + return ret; +} +EXPORT_SYMBOL_GPL(regulator_map_voltage_linear_range); + +/** + * regulator_get_voltage_sel_regmap - standard get_voltage_sel for regmap users + * + * @rdev: regulator to operate on + * + * Regulators that use regmap for their register I/O can set the + * vsel_reg and vsel_mask fields in their descriptor and then use this + * as their get_voltage_vsel operation, saving some code. + */ +int regulator_get_voltage_sel_regmap(struct regulator_dev *rdev) +{ + unsigned int val; + int ret; + + ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val); + if (ret != 0) + return ret; + + val &= rdev->desc->vsel_mask; + val >>= ffs(rdev->desc->vsel_mask) - 1; + + return val; +} +EXPORT_SYMBOL_GPL(regulator_get_voltage_sel_regmap); + +/** + * regulator_map_voltage_iterate - map_voltage() based on list_voltage() + * + * @rdev: Regulator to operate on + * @min_uV: Lower bound for voltage + * @max_uV: Upper bound for voltage + * + * Drivers implementing set_voltage_sel() and list_voltage() can use + * this as their map_voltage() operation. It will find a suitable + * voltage by calling list_voltage() until it gets something in bounds + * for the requested voltages. + */ +int regulator_map_voltage_iterate(struct regulator_dev *rdev, + int min_uV, int max_uV) +{ + int best_val = INT_MAX; + int selector = 0; + int i, ret; + + /* Find the smallest voltage that falls within the specified + * range. + */ + for (i = 0; i < rdev->desc->n_voltages; i++) { + ret = rdev->desc->ops->list_voltage(rdev, i); + if (ret < 0) + continue; + + if (ret < best_val && ret >= min_uV && ret <= max_uV) { + best_val = ret; + selector = i; + } + } + + if (best_val != INT_MAX) + return selector; + else + return -EINVAL; +} +EXPORT_SYMBOL_GPL(regulator_map_voltage_iterate); + + |