// SPDX-License-Identifier: GPL-2.0
// Copyright (C) STMicroelectronics 2019
// Author(s): Fabrice Gasnier <fabrice.gasnier@st.com>.

#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>

/* STM32H7 SYSCFG register */
#define STM32H7_SYSCFG_PMCR             0x04
#define STM32H7_SYSCFG_BOOSTE_MASK      BIT(8)

/* STM32MP1 SYSCFG has set and clear registers */
#define STM32MP1_SYSCFG_PMCSETR         0x04
#define STM32MP1_SYSCFG_PMCCLRR         0x44
#define STM32MP1_SYSCFG_EN_BOOSTER_MASK BIT(8)

static const struct regulator_ops stm32h7_booster_ops = {
        .enable         = regulator_enable_regmap,
        .disable        = regulator_disable_regmap,
        .is_enabled     = regulator_is_enabled_regmap,
};

static const struct regulator_desc stm32h7_booster_desc = {
        .name = "booster",
        .supply_name = "vdda",
        .n_voltages = 1,
        .type = REGULATOR_VOLTAGE,
        .fixed_uV = 3300000,
        .ramp_delay = 66000, /* up to 50us to stabilize */
        .ops = &stm32h7_booster_ops,
        .enable_reg = STM32H7_SYSCFG_PMCR,
        .enable_mask = STM32H7_SYSCFG_BOOSTE_MASK,
        .owner = THIS_MODULE,
};

static int stm32mp1_booster_enable(struct regulator_dev *rdev)
{
        return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCSETR,
                            STM32MP1_SYSCFG_EN_BOOSTER_MASK);
}

static int stm32mp1_booster_disable(struct regulator_dev *rdev)
{
        return regmap_write(rdev->regmap, STM32MP1_SYSCFG_PMCCLRR,
                            STM32MP1_SYSCFG_EN_BOOSTER_MASK);
}

static const struct regulator_ops stm32mp1_booster_ops = {
        .enable         = stm32mp1_booster_enable,
        .disable        = stm32mp1_booster_disable,
        .is_enabled     = regulator_is_enabled_regmap,
};

static const struct regulator_desc stm32mp1_booster_desc = {
        .name = "booster",
        .supply_name = "vdda",
        .n_voltages = 1,
        .type = REGULATOR_VOLTAGE,
        .fixed_uV = 3300000,
        .ramp_delay = 66000,
        .ops = &stm32mp1_booster_ops,
        .enable_reg = STM32MP1_SYSCFG_PMCSETR,
        .enable_mask = STM32MP1_SYSCFG_EN_BOOSTER_MASK,
        .owner = THIS_MODULE,
};

static int stm32_booster_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct device_node *np = pdev->dev.of_node;
        struct regulator_config config = { };
        const struct regulator_desc *desc;
        struct regulator_dev *rdev;
        struct regmap *regmap;
        int ret;

        regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
        if (IS_ERR(regmap))
                return PTR_ERR(regmap);

        desc = device_get_match_data(dev);

        config.regmap = regmap;
        config.dev = dev;
        config.of_node = np;
        config.init_data = of_get_regulator_init_data(dev, np, desc);

        rdev = devm_regulator_register(dev, desc, &config);
        if (IS_ERR(rdev)) {
                ret = PTR_ERR(rdev);
                dev_err(dev, "register failed with error %d\n", ret);
                return ret;
        }

        return 0;
}

static const struct of_device_id __maybe_unused stm32_booster_of_match[] = {
        {
                .compatible = "st,stm32h7-booster",
                .data = (void *)&stm32h7_booster_desc
        }, {
                .compatible = "st,stm32mp1-booster",
                .data = (void *)&stm32mp1_booster_desc
        }, {
        },
};
MODULE_DEVICE_TABLE(of, stm32_booster_of_match);

static struct platform_driver stm32_booster_driver = {
        .probe = stm32_booster_probe,
        .driver = {
                .name  = "stm32-booster",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
                .of_match_table = of_match_ptr(stm32_booster_of_match),
        },
};
module_platform_driver(stm32_booster_driver);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
MODULE_DESCRIPTION("STMicroelectronics STM32 booster regulator driver");
MODULE_ALIAS("platform:stm32-booster");