diff options
Diffstat (limited to 'drivers/regulator/helpers.c')
| -rw-r--r-- | drivers/regulator/helpers.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/drivers/regulator/helpers.c b/drivers/regulator/helpers.c new file mode 100644 index 00000000000..6e30df14714 --- /dev/null +++ b/drivers/regulator/helpers.c @@ -0,0 +1,447 @@ +/* + * helpers.c -- Voltage/Current Regulator framework helper functions. + * + * Copyright 2007, 2008 Wolfson Microelectronics PLC. + * Copyright 2008 SlimLogic Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + */ + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/regulator/driver.h> +#include <linux/module.h> + +/** + * regulator_is_enabled_regmap - standard is_enabled() for regmap users + * + * @rdev: regulator to operate on + * + * Regulators that use regmap for their register I/O can set the + * enable_reg and enable_mask fields in their descriptor and then use + * this as their is_enabled operation, saving some code. + */ +int regulator_is_enabled_regmap(struct regulator_dev *rdev) +{ + unsigned int val; + int ret; + + ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val); + if (ret != 0) + return ret; + + if (rdev->desc->enable_is_inverted) + return (val & rdev->desc->enable_mask) == 0; + else + return (val & rdev->desc->enable_mask) != 0; +} +EXPORT_SYMBOL_GPL(regulator_is_enabled_regmap); + +/** + * regulator_enable_regmap - standard enable() for regmap users + * + * @rdev: regulator to operate on + * + * Regulators that use regmap for their register I/O can set the + * enable_reg and enable_mask fields in their descriptor and then use + * this as their enable() operation, saving some code. + */ +int regulator_enable_regmap(struct regulator_dev *rdev) +{ + unsigned int val; + + if (rdev->desc->enable_is_inverted) + val = 0; + else + val = rdev->desc->enable_mask; + + return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg, + rdev->desc->enable_mask, val); +} +EXPORT_SYMBOL_GPL(regulator_enable_regmap); + +/** + * regulator_disable_regmap - standard disable() for regmap users + * + * @rdev: regulator to operate on + * + * Regulators that use regmap for their register I/O can set the + * enable_reg and enable_mask fields in their descriptor and then use + * this as their disable() operation, saving some code. + */ +int regulator_disable_regmap(struct regulator_dev *rdev) +{ + unsigned int val; + + if (rdev->desc->enable_is_inverted) + val = rdev->desc->enable_mask; + else + val = 0; + + return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg, + rdev->desc->enable_mask, val); +} +EXPORT_SYMBOL_GPL(regulator_disable_regmap); + +/** + * 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_set_voltage_sel_regmap - standard set_voltage_sel for regmap users + * + * @rdev: regulator to operate on + * @sel: Selector to set + * + * 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 set_voltage_vsel operation, saving some code. + */ +int regulator_set_voltage_sel_regmap(struct regulator_dev *rdev, unsigned sel) +{ + int ret; + + sel <<= ffs(rdev->desc->vsel_mask) - 1; + + ret = regmap_update_bits(rdev->regmap, rdev->desc->vsel_reg, + rdev->desc->vsel_mask, sel); + if (ret) + return ret; + + if (rdev->desc->apply_bit) + ret = regmap_update_bits(rdev->regmap, rdev->desc->apply_reg, + rdev->desc->apply_bit, + rdev->desc->apply_bit); + return ret; +} +EXPORT_SYMBOL_GPL(regulator_set_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); + +/** + * regulator_map_voltage_ascend - map_voltage() for ascendant voltage list + * + * @rdev: Regulator to operate on + * @min_uV: Lower bound for voltage + * @max_uV: Upper bound for voltage + * + * Drivers that have ascendant voltage list can use this as their + * map_voltage() operation. + */ +int regulator_map_voltage_ascend(struct regulator_dev *rdev, + int min_uV, int max_uV) +{ + int i, ret; + + for (i = 0; i < rdev->desc->n_voltages; i++) { + ret = rdev->desc->ops->list_voltage(rdev, i); + if (ret < 0) + continue; + + if (ret > max_uV) + break; + + if (ret >= min_uV && ret <= max_uV) + return i; + } + + return -EINVAL; +} +EXPORT_SYMBOL_GPL(regulator_map_voltage_ascend); + +/** + * 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; + + /* Allow uV_step to be 0 for fixed voltage */ + if (rdev->desc->n_voltages == 1 && rdev->desc->uV_step == 0) { + if (min_uV <= rdev->desc->min_uV && rdev->desc->min_uV <= max_uV) + return 0; + else + return -EINVAL; + } + + if (!rdev->desc->uV_step) { + BUG_ON(!rdev->desc->uV_step); + return -EINVAL; + } + + if (min_uV < rdev->desc->min_uV) + min_uV = rdev->desc->min_uV; + + ret = DIV_ROUND_UP(min_uV - rdev->desc->min_uV, rdev->desc->uV_step); + if (ret < 0) + return ret; + + ret += rdev->desc->linear_min_sel; + + /* 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); + +/** + * regulator_map_voltage_linear - 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++) { + range = &rdev->desc->linear_ranges[i]; + + if (!(min_uV <= range->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; + + break; + } + + if (i == rdev->desc->n_linear_ranges) + return -EINVAL; + + /* 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_range); + +/** + * 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; + if (selector < rdev->desc->linear_min_sel) + return 0; + + selector -= rdev->desc->linear_min_sel; + + return rdev->desc->min_uV + (rdev->desc->uV_step * selector); +} +EXPORT_SYMBOL_GPL(regulator_list_voltage_linear); + +/** + * 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) +{ + const struct regulator_linear_range *range; + int 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++) { + range = &rdev->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_list_voltage_linear_range); + +/** + * regulator_list_voltage_table - List voltages with table based mapping + * + * @rdev: Regulator device + * @selector: Selector to convert into a voltage + * + * Regulators with table based mapping between voltages and + * selectors can set volt_table in the regulator descriptor + * and then use this function as their list_voltage() operation. + */ +int regulator_list_voltage_table(struct regulator_dev *rdev, + unsigned int selector) +{ + if (!rdev->desc->volt_table) { + BUG_ON(!rdev->desc->volt_table); + return -EINVAL; + } + + if (selector >= rdev->desc->n_voltages) + return -EINVAL; + + return rdev->desc->volt_table[selector]; +} +EXPORT_SYMBOL_GPL(regulator_list_voltage_table); + +/** + * regulator_set_bypass_regmap - Default set_bypass() using regmap + * + * @rdev: device to operate on. + * @enable: state to set. + */ +int regulator_set_bypass_regmap(struct regulator_dev *rdev, bool enable) +{ + unsigned int val; + + if (enable) + val = rdev->desc->bypass_mask; + else + val = 0; + + return regmap_update_bits(rdev->regmap, rdev->desc->bypass_reg, + rdev->desc->bypass_mask, val); +} +EXPORT_SYMBOL_GPL(regulator_set_bypass_regmap); + +/** + * regulator_get_bypass_regmap - Default get_bypass() using regmap + * + * @rdev: device to operate on. + * @enable: current state. + */ +int regulator_get_bypass_regmap(struct regulator_dev *rdev, bool *enable) +{ + unsigned int val; + int ret; + + ret = regmap_read(rdev->regmap, rdev->desc->bypass_reg, &val); + if (ret != 0) + return ret; + + *enable = val & rdev->desc->bypass_mask; + + return 0; +} +EXPORT_SYMBOL_GPL(regulator_get_bypass_regmap); |