root/drivers/regulator/max14577-regulator.c
// SPDX-License-Identifier: GPL-2.0+
//
// max14577.c - Regulator driver for the Maxim 14577/77836
//
// Copyright (C) 2013,2014 Samsung Electronics
// Krzysztof Kozlowski <krzk@kernel.org>

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/mfd/max14577.h>
#include <linux/mfd/max14577-private.h>
#include <linux/regulator/of_regulator.h>

static int max14577_reg_is_enabled(struct regulator_dev *rdev)
{
        int rid = rdev_get_id(rdev);
        struct regmap *rmap = rdev->regmap;
        u8 reg_data;

        switch (rid) {
        case MAX14577_CHARGER:
                max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL2, &reg_data);
                if ((reg_data & CHGCTRL2_MBCHOSTEN_MASK) == 0)
                        return 0;
                max14577_read_reg(rmap, MAX14577_CHG_REG_STATUS3, &reg_data);
                if ((reg_data & STATUS3_CGMBC_MASK) == 0)
                        return 0;
                /* MBCHOSTEN and CGMBC are on */
                return 1;
        default:
                return -EINVAL;
        }
}

static int max14577_reg_get_current_limit(struct regulator_dev *rdev)
{
        u8 reg_data;
        struct regmap *rmap = rdev->regmap;
        struct max14577 *max14577 = rdev_get_drvdata(rdev);
        const struct maxim_charger_current *limits =
                &maxim_charger_currents[max14577->dev_type];
        int ret;

        if (rdev_get_id(rdev) != MAX14577_CHARGER)
                return -EINVAL;

        ret = max14577_read_reg(rmap, MAX14577_CHG_REG_CHG_CTRL4, &reg_data);
        if (ret < 0)
                return ret;

        if ((reg_data & CHGCTRL4_MBCICHWRCL_MASK) == 0)
                return limits->min;

        reg_data = ((reg_data & CHGCTRL4_MBCICHWRCH_MASK) >>
                        CHGCTRL4_MBCICHWRCH_SHIFT);
        return limits->high_start + reg_data * limits->high_step;
}

static int max14577_reg_set_current_limit(struct regulator_dev *rdev,
                int min_uA, int max_uA)
{
        u8 reg_data;
        int ret;
        struct max14577 *max14577 = rdev_get_drvdata(rdev);
        const struct maxim_charger_current *limits =
                &maxim_charger_currents[max14577->dev_type];

        if (rdev_get_id(rdev) != MAX14577_CHARGER)
                return -EINVAL;

        ret = maxim_charger_calc_reg_current(limits, min_uA, max_uA, &reg_data);
        if (ret)
                return ret;

        return max14577_update_reg(rdev->regmap, MAX14577_CHG_REG_CHG_CTRL4,
                        CHGCTRL4_MBCICHWRCL_MASK | CHGCTRL4_MBCICHWRCH_MASK,
                        reg_data);
}

static const struct regulator_ops max14577_safeout_ops = {
        .is_enabled             = regulator_is_enabled_regmap,
        .enable                 = regulator_enable_regmap,
        .disable                = regulator_disable_regmap,
        .list_voltage           = regulator_list_voltage_linear,
};

static const struct regulator_ops max14577_charger_ops = {
        .is_enabled             = max14577_reg_is_enabled,
        .enable                 = regulator_enable_regmap,
        .disable                = regulator_disable_regmap,
        .get_current_limit      = max14577_reg_get_current_limit,
        .set_current_limit      = max14577_reg_set_current_limit,
};

#define MAX14577_SAFEOUT_REG    { \
        .name           = "SAFEOUT", \
        .of_match       = of_match_ptr("SAFEOUT"), \
        .regulators_node = of_match_ptr("regulators"), \
        .id             = MAX14577_SAFEOUT, \
        .ops            = &max14577_safeout_ops, \
        .type           = REGULATOR_VOLTAGE, \
        .owner          = THIS_MODULE, \
        .n_voltages     = 1, \
        .min_uV         = MAX14577_REGULATOR_SAFEOUT_VOLTAGE, \
        .enable_reg     = MAX14577_REG_CONTROL2, \
        .enable_mask    = CTRL2_SFOUTORD_MASK, \
}
#define MAX14577_CHARGER_REG    { \
        .name           = "CHARGER", \
        .of_match       = of_match_ptr("CHARGER"), \
        .regulators_node = of_match_ptr("regulators"), \
        .id             = MAX14577_CHARGER, \
        .ops            = &max14577_charger_ops, \
        .type           = REGULATOR_CURRENT, \
        .owner          = THIS_MODULE, \
        .enable_reg     = MAX14577_CHG_REG_CHG_CTRL2, \
        .enable_mask    = CHGCTRL2_MBCHOSTEN_MASK, \
}

static const struct regulator_desc max14577_supported_regulators[] = {
        [MAX14577_SAFEOUT] = MAX14577_SAFEOUT_REG,
        [MAX14577_CHARGER] = MAX14577_CHARGER_REG,
};

static const struct regulator_ops max77836_ldo_ops = {
        .is_enabled             = regulator_is_enabled_regmap,
        .enable                 = regulator_enable_regmap,
        .disable                = regulator_disable_regmap,
        .list_voltage           = regulator_list_voltage_linear,
        .map_voltage            = regulator_map_voltage_linear,
        .get_voltage_sel        = regulator_get_voltage_sel_regmap,
        .set_voltage_sel        = regulator_set_voltage_sel_regmap,
        /* TODO: add .set_suspend_mode */
};

#define MAX77836_LDO_REG(num)   { \
        .name           = "LDO" # num, \
        .of_match       = of_match_ptr("LDO" # num), \
        .regulators_node = of_match_ptr("regulators"), \
        .id             = MAX77836_LDO ## num, \
        .ops            = &max77836_ldo_ops, \
        .type           = REGULATOR_VOLTAGE, \
        .owner          = THIS_MODULE, \
        .n_voltages     = MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM, \
        .min_uV         = MAX77836_REGULATOR_LDO_VOLTAGE_MIN, \
        .uV_step        = MAX77836_REGULATOR_LDO_VOLTAGE_STEP, \
        .enable_reg     = MAX77836_LDO_REG_CNFG1_LDO ## num, \
        .enable_mask    = MAX77836_CNFG1_LDO_PWRMD_MASK, \
        .vsel_reg       = MAX77836_LDO_REG_CNFG1_LDO ## num, \
        .vsel_mask      = MAX77836_CNFG1_LDO_TV_MASK, \
}

static const struct regulator_desc max77836_supported_regulators[] = {
        [MAX14577_SAFEOUT] = MAX14577_SAFEOUT_REG,
        [MAX14577_CHARGER] = MAX14577_CHARGER_REG,
        [MAX77836_LDO1] = MAX77836_LDO_REG(1),
        [MAX77836_LDO2] = MAX77836_LDO_REG(2),
};

/*
 * Registers for regulators of max77836 use different I2C slave addresses so
 * different regmaps must be used for them.
 *
 * Returns proper regmap for accessing regulator passed by id.
 */
static struct regmap *max14577_get_regmap(struct max14577 *max14577,
                int reg_id)
{
        switch (max14577->dev_type) {
        case MAXIM_DEVICE_TYPE_MAX77836:
                switch (reg_id) {
                case MAX77836_SAFEOUT ... MAX77836_CHARGER:
                        return max14577->regmap;
                default:
                        /* MAX77836_LDO1 ... MAX77836_LDO2 */
                        return max14577->regmap_pmic;
                }

        case MAXIM_DEVICE_TYPE_MAX14577:
        default:
                return max14577->regmap;
        }
}

static int max14577_regulator_probe(struct platform_device *pdev)
{
        struct max14577 *max14577 = dev_get_drvdata(pdev->dev.parent);
        struct max14577_platform_data *pdata = dev_get_platdata(max14577->dev);
        int i, ret = 0;
        struct regulator_config config = {};
        const struct regulator_desc *supported_regulators;
        unsigned int supported_regulators_size;
        enum maxim_device_type dev_type = max14577->dev_type;

        switch (dev_type) {
        case MAXIM_DEVICE_TYPE_MAX77836:
                supported_regulators = max77836_supported_regulators;
                supported_regulators_size = ARRAY_SIZE(max77836_supported_regulators);
                break;
        case MAXIM_DEVICE_TYPE_MAX14577:
        default:
                supported_regulators = max14577_supported_regulators;
                supported_regulators_size = ARRAY_SIZE(max14577_supported_regulators);
        }

        config.dev = max14577->dev;
        config.driver_data = max14577;

        for (i = 0; i < supported_regulators_size; i++) {
                struct regulator_dev *regulator;
                /*
                 * Index of supported_regulators[] is also the id and must
                 * match index of pdata->regulators[].
                 */
                if (pdata && pdata->regulators) {
                        config.init_data = pdata->regulators[i].initdata;
                        config.of_node = pdata->regulators[i].of_node;
                }
                config.regmap = max14577_get_regmap(max14577,
                                supported_regulators[i].id);

                regulator = devm_regulator_register(&pdev->dev,
                                &supported_regulators[i], &config);
                if (IS_ERR(regulator)) {
                        ret = PTR_ERR(regulator);
                        dev_err(&pdev->dev,
                                        "Regulator init failed for %d/%s with error: %d\n",
                                        i, supported_regulators[i].name, ret);
                        return ret;
                }
        }

        return ret;
}

static const struct platform_device_id max14577_regulator_id[] = {
        { "max14577-regulator", MAXIM_DEVICE_TYPE_MAX14577, },
        { "max77836-regulator", MAXIM_DEVICE_TYPE_MAX77836, },
        { }
};
MODULE_DEVICE_TABLE(platform, max14577_regulator_id);

static struct platform_driver max14577_regulator_driver = {
        .driver = {
                   .name = "max14577-regulator",
                   .probe_type = PROBE_PREFER_ASYNCHRONOUS,
                   },
        .probe          = max14577_regulator_probe,
        .id_table       = max14577_regulator_id,
};

static int __init max14577_regulator_init(void)
{
        BUILD_BUG_ON(ARRAY_SIZE(max14577_supported_regulators) != MAX14577_REGULATOR_NUM);
        BUILD_BUG_ON(ARRAY_SIZE(max77836_supported_regulators) != MAX77836_REGULATOR_NUM);

        BUILD_BUG_ON(MAX77836_REGULATOR_LDO_VOLTAGE_MIN +
                        (MAX77836_REGULATOR_LDO_VOLTAGE_STEP *
                          (MAX77836_REGULATOR_LDO_VOLTAGE_STEPS_NUM - 1)) !=
                        MAX77836_REGULATOR_LDO_VOLTAGE_MAX);

        return platform_driver_register(&max14577_regulator_driver);
}
subsys_initcall(max14577_regulator_init);

static void __exit max14577_regulator_exit(void)
{
        platform_driver_unregister(&max14577_regulator_driver);
}
module_exit(max14577_regulator_exit);

MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
MODULE_DESCRIPTION("Maxim 14577/77836 regulator driver");
MODULE_LICENSE("GPL");