root/drivers/regulator/max8925-regulator.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Regulators driver for Maxim max8925
 *
 * Copyright (C) 2009 Marvell International Ltd.
 *      Haojian Zhuang <haojian.zhuang@marvell.com>
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/max8925.h>
#include <linux/of.h>
#include <linux/regulator/of_regulator.h>

#define SD1_DVM_VMIN            850000
#define SD1_DVM_VMAX            1000000
#define SD1_DVM_STEP            50000
#define SD1_DVM_SHIFT           5               /* SDCTL1 bit5 */
#define SD1_DVM_EN              6               /* SDV1 bit 6 */

/* bit definitions in LDO control registers */
#define LDO_SEQ_I2C             0x7             /* Power U/D by i2c */
#define LDO_SEQ_MASK            0x7             /* Power U/D sequence mask */
#define LDO_SEQ_SHIFT           2               /* Power U/D sequence offset */
#define LDO_I2C_EN              0x1             /* Enable by i2c */
#define LDO_I2C_EN_MASK         0x1             /* Enable mask by i2c */
#define LDO_I2C_EN_SHIFT        0               /* Enable offset by i2c */

struct max8925_regulator_info {
        struct regulator_desc   desc;
        struct i2c_client       *i2c;

        int     vol_reg;
        int     enable_reg;
};

static int max8925_set_voltage_sel(struct regulator_dev *rdev,
                                   unsigned int selector)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
        unsigned char mask = rdev->desc->n_voltages - 1;

        return max8925_set_bits(info->i2c, info->vol_reg, mask, selector);
}

static int max8925_get_voltage_sel(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
        unsigned char data, mask;
        int ret;

        ret = max8925_reg_read(info->i2c, info->vol_reg);
        if (ret < 0)
                return ret;
        mask = rdev->desc->n_voltages - 1;
        data = ret & mask;

        return data;
}

static int max8925_enable(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);

        return max8925_set_bits(info->i2c, info->enable_reg,
                                LDO_SEQ_MASK << LDO_SEQ_SHIFT |
                                LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
                                LDO_SEQ_I2C << LDO_SEQ_SHIFT |
                                LDO_I2C_EN << LDO_I2C_EN_SHIFT);
}

static int max8925_disable(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);

        return max8925_set_bits(info->i2c, info->enable_reg,
                                LDO_SEQ_MASK << LDO_SEQ_SHIFT |
                                LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
                                LDO_SEQ_I2C << LDO_SEQ_SHIFT);
}

static int max8925_is_enabled(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
        int ldo_seq, ret;

        ret = max8925_reg_read(info->i2c, info->enable_reg);
        if (ret < 0)
                return ret;
        ldo_seq = (ret >> LDO_SEQ_SHIFT) & LDO_SEQ_MASK;
        if (ldo_seq != LDO_SEQ_I2C)
                return 1;
        else
                return ret & (LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT);
}

static int max8925_set_dvm_voltage(struct regulator_dev *rdev, int uV)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
        unsigned char data, mask;

        if (uV < SD1_DVM_VMIN || uV > SD1_DVM_VMAX)
                return -EINVAL;

        data = DIV_ROUND_UP(uV - SD1_DVM_VMIN, SD1_DVM_STEP);
        data <<= SD1_DVM_SHIFT;
        mask = 3 << SD1_DVM_SHIFT;

        return max8925_set_bits(info->i2c, info->enable_reg, mask, data);
}

static int max8925_set_dvm_enable(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);

        return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN,
                                1 << SD1_DVM_EN);
}

static int max8925_set_dvm_disable(struct regulator_dev *rdev)
{
        struct max8925_regulator_info *info = rdev_get_drvdata(rdev);

        return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN, 0);
}

static const struct regulator_ops max8925_regulator_sdv_ops = {
        .map_voltage            = regulator_map_voltage_linear,
        .list_voltage           = regulator_list_voltage_linear,
        .set_voltage_sel        = max8925_set_voltage_sel,
        .get_voltage_sel        = max8925_get_voltage_sel,
        .enable                 = max8925_enable,
        .disable                = max8925_disable,
        .is_enabled             = max8925_is_enabled,
        .set_suspend_voltage    = max8925_set_dvm_voltage,
        .set_suspend_enable     = max8925_set_dvm_enable,
        .set_suspend_disable    = max8925_set_dvm_disable,
};

static const struct regulator_ops max8925_regulator_ldo_ops = {
        .map_voltage            = regulator_map_voltage_linear,
        .list_voltage           = regulator_list_voltage_linear,
        .set_voltage_sel        = max8925_set_voltage_sel,
        .get_voltage_sel        = max8925_get_voltage_sel,
        .enable                 = max8925_enable,
        .disable                = max8925_disable,
        .is_enabled             = max8925_is_enabled,
};

#define MAX8925_SDV(_id, min, max, step)                        \
{                                                               \
        .desc   = {                                             \
                .name   = "SDV" #_id,                           \
                .of_match = of_match_ptr("SDV" #_id),           \
                .regulators_node = of_match_ptr("regulators"),  \
                .ops    = &max8925_regulator_sdv_ops,           \
                .type   = REGULATOR_VOLTAGE,                    \
                .id     = MAX8925_ID_SD##_id,                   \
                .owner  = THIS_MODULE,                          \
                .n_voltages = 64,                               \
                .min_uV = min * 1000,                           \
                .uV_step = step * 1000,                         \
        },                                                      \
        .vol_reg        = MAX8925_SDV##_id,                     \
        .enable_reg     = MAX8925_SDCTL##_id,                   \
}

#define MAX8925_LDO(_id, min, max, step)                        \
{                                                               \
        .desc   = {                                             \
                .name   = "LDO" #_id,                           \
                .of_match = of_match_ptr("LDO" #_id),           \
                .regulators_node = of_match_ptr("regulators"),  \
                .ops    = &max8925_regulator_ldo_ops,           \
                .type   = REGULATOR_VOLTAGE,                    \
                .id     = MAX8925_ID_LDO##_id,                  \
                .owner  = THIS_MODULE,                          \
                .n_voltages = 64,                               \
                .min_uV = min * 1000,                           \
                .uV_step = step * 1000,                         \
        },                                                      \
        .vol_reg        = MAX8925_LDOVOUT##_id,                 \
        .enable_reg     = MAX8925_LDOCTL##_id,                  \
}

static struct max8925_regulator_info max8925_regulator_info[] = {
        MAX8925_SDV(1, 637.5, 1425, 12.5),
        MAX8925_SDV(2,   650, 2225,   25),
        MAX8925_SDV(3,   750, 3900,   50),

        MAX8925_LDO(1,  750, 3900, 50),
        MAX8925_LDO(2,  650, 2250, 25),
        MAX8925_LDO(3,  650, 2250, 25),
        MAX8925_LDO(4,  750, 3900, 50),
        MAX8925_LDO(5,  750, 3900, 50),
        MAX8925_LDO(6,  750, 3900, 50),
        MAX8925_LDO(7,  750, 3900, 50),
        MAX8925_LDO(8,  750, 3900, 50),
        MAX8925_LDO(9,  750, 3900, 50),
        MAX8925_LDO(10, 750, 3900, 50),
        MAX8925_LDO(11, 750, 3900, 50),
        MAX8925_LDO(12, 750, 3900, 50),
        MAX8925_LDO(13, 750, 3900, 50),
        MAX8925_LDO(14, 750, 3900, 50),
        MAX8925_LDO(15, 750, 3900, 50),
        MAX8925_LDO(16, 750, 3900, 50),
        MAX8925_LDO(17, 650, 2250, 25),
        MAX8925_LDO(18, 650, 2250, 25),
        MAX8925_LDO(19, 750, 3900, 50),
        MAX8925_LDO(20, 750, 3900, 50),
};

static int max8925_regulator_probe(struct platform_device *pdev)
{
        struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
        struct regulator_init_data *pdata = dev_get_platdata(&pdev->dev);
        struct regulator_config config = { };
        struct max8925_regulator_info *ri;
        struct resource *res;
        struct regulator_dev *rdev;
        int i;

        res = platform_get_resource(pdev, IORESOURCE_REG, 0);
        if (!res) {
                dev_err(&pdev->dev, "No REG resource!\n");
                return -EINVAL;
        }
        for (i = 0; i < ARRAY_SIZE(max8925_regulator_info); i++) {
                ri = &max8925_regulator_info[i];
                if (ri->vol_reg == res->start)
                        break;
        }

        if (i == ARRAY_SIZE(max8925_regulator_info)) {
                dev_err(&pdev->dev, "Failed to find regulator %llu\n",
                        (unsigned long long)res->start);
                return -EINVAL;
        }
        ri->i2c = chip->i2c;

        config.dev = chip->dev;
        config.driver_data = ri;

        if (pdata)
                config.init_data = pdata;

        rdev = devm_regulator_register(&pdev->dev, &ri->desc, &config);
        if (IS_ERR(rdev)) {
                dev_err(&pdev->dev, "failed to register regulator %s\n",
                                ri->desc.name);
                return PTR_ERR(rdev);
        }

        platform_set_drvdata(pdev, rdev);
        return 0;
}

static struct platform_driver max8925_regulator_driver = {
        .driver         = {
                .name   = "max8925-regulator",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
        .probe          = max8925_regulator_probe,
};

static int __init max8925_regulator_init(void)
{
        return platform_driver_register(&max8925_regulator_driver);
}
subsys_initcall(max8925_regulator_init);

static void __exit max8925_regulator_exit(void)
{
        platform_driver_unregister(&max8925_regulator_driver);
}
module_exit(max8925_regulator_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_DESCRIPTION("Regulator Driver for Maxim 8925 PMIC");
MODULE_ALIAS("platform:max8925-regulator");