// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2017 Spreadtrum Communications Inc.
 */

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/mfd/sc27xx-pmic.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
#include <uapi/linux/usb/charger.h>

#define SPRD_PMIC_INT_MASK_STATUS       0x0
#define SPRD_PMIC_INT_RAW_STATUS        0x4
#define SPRD_PMIC_INT_EN                0x8

#define SPRD_SC2730_IRQ_BASE            0x80
#define SPRD_SC2730_IRQ_NUMS            10
#define SPRD_SC2730_CHG_DET             0x1b9c
#define SPRD_SC2731_IRQ_BASE            0x140
#define SPRD_SC2731_IRQ_NUMS            16
#define SPRD_SC2731_CHG_DET             0xedc

/* PMIC charger detection definition */
#define SPRD_PMIC_CHG_DET_DELAY_US      200000
#define SPRD_PMIC_CHG_DET_TIMEOUT       2000000
#define SPRD_PMIC_CHG_DET_DONE          BIT(11)
#define SPRD_PMIC_SDP_TYPE              BIT(7)
#define SPRD_PMIC_DCP_TYPE              BIT(6)
#define SPRD_PMIC_CDP_TYPE              BIT(5)
#define SPRD_PMIC_CHG_TYPE_MASK         GENMASK(7, 5)

struct sprd_pmic {
        struct regmap *regmap;
        struct device *dev;
        struct regmap_irq *irqs;
        struct regmap_irq_chip irq_chip;
        struct regmap_irq_chip_data *irq_data;
        const struct sprd_pmic_data *pdata;
        int irq;
};

struct sprd_pmic_data {
        u32 irq_base;
        u32 num_irqs;
        u32 charger_det;
};

/*
 * Since different PMICs of SC27xx series can have different interrupt
 * base address and irq number, we should save irq number and irq base
 * in the device data structure.
 */
static const struct sprd_pmic_data sc2730_data = {
        .irq_base = SPRD_SC2730_IRQ_BASE,
        .num_irqs = SPRD_SC2730_IRQ_NUMS,
        .charger_det = SPRD_SC2730_CHG_DET,
};

static const struct sprd_pmic_data sc2731_data = {
        .irq_base = SPRD_SC2731_IRQ_BASE,
        .num_irqs = SPRD_SC2731_IRQ_NUMS,
        .charger_det = SPRD_SC2731_CHG_DET,
};

enum usb_charger_type sprd_pmic_detect_charger_type(struct device *dev)
{
        struct spi_device *spi = to_spi_device(dev);
        struct sprd_pmic *ddata = spi_get_drvdata(spi);
        const struct sprd_pmic_data *pdata = ddata->pdata;
        enum usb_charger_type type;
        u32 val;
        int ret;

        ret = regmap_read_poll_timeout(ddata->regmap, pdata->charger_det, val,
                                       (val & SPRD_PMIC_CHG_DET_DONE),
                                       SPRD_PMIC_CHG_DET_DELAY_US,
                                       SPRD_PMIC_CHG_DET_TIMEOUT);
        if (ret) {
                dev_err(&spi->dev, "failed to detect charger type\n");
                return UNKNOWN_TYPE;
        }

        switch (val & SPRD_PMIC_CHG_TYPE_MASK) {
        case SPRD_PMIC_CDP_TYPE:
                type = CDP_TYPE;
                break;
        case SPRD_PMIC_DCP_TYPE:
                type = DCP_TYPE;
                break;
        case SPRD_PMIC_SDP_TYPE:
                type = SDP_TYPE;
                break;
        default:
                type = UNKNOWN_TYPE;
                break;
        }

        return type;
}
EXPORT_SYMBOL_GPL(sprd_pmic_detect_charger_type);

static int sprd_pmic_spi_write(void *context, const void *data, size_t count)
{
        struct device *dev = context;
        struct spi_device *spi = to_spi_device(dev);

        return spi_write(spi, data, count);
}

static int sprd_pmic_spi_read(void *context,
                              const void *reg, size_t reg_size,
                              void *val, size_t val_size)
{
        struct device *dev = context;
        struct spi_device *spi = to_spi_device(dev);
        u32 rx_buf[2] = { 0 };
        int ret;

        /* Now we only support one PMIC register to read every time. */
        if (reg_size != sizeof(u32) || val_size != sizeof(u32))
                return -EINVAL;

        /* Copy address to read from into first element of SPI buffer. */
        memcpy(rx_buf, reg, sizeof(u32));
        ret = spi_read(spi, rx_buf, 1);
        if (ret < 0)
                return ret;

        memcpy(val, rx_buf, val_size);
        return 0;
}

static const struct regmap_bus sprd_pmic_regmap = {
        .write = sprd_pmic_spi_write,
        .read = sprd_pmic_spi_read,
        .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
        .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
};

static const struct regmap_config sprd_pmic_config = {
        .reg_bits = 32,
        .val_bits = 32,
        .reg_stride = 4,
        .max_register = 0xffff,
};

static int sprd_pmic_probe(struct spi_device *spi)
{
        struct sprd_pmic *ddata;
        const struct sprd_pmic_data *pdata;
        int ret, i;

        pdata = of_device_get_match_data(&spi->dev);
        if (!pdata) {
                dev_err(&spi->dev, "No matching driver data found\n");
                return -EINVAL;
        }

        ddata = devm_kzalloc(&spi->dev, sizeof(*ddata), GFP_KERNEL);
        if (!ddata)
                return -ENOMEM;

        ddata->regmap = devm_regmap_init(&spi->dev, &sprd_pmic_regmap,
                                         &spi->dev, &sprd_pmic_config);
        if (IS_ERR(ddata->regmap)) {
                ret = PTR_ERR(ddata->regmap);
                dev_err(&spi->dev, "Failed to allocate register map %d\n", ret);
                return ret;
        }

        spi_set_drvdata(spi, ddata);
        ddata->dev = &spi->dev;
        ddata->irq = spi->irq;
        ddata->pdata = pdata;

        ddata->irq_chip.name = dev_name(&spi->dev);
        ddata->irq_chip.status_base =
                pdata->irq_base + SPRD_PMIC_INT_MASK_STATUS;
        ddata->irq_chip.unmask_base = pdata->irq_base + SPRD_PMIC_INT_EN;
        ddata->irq_chip.ack_base = 0;
        ddata->irq_chip.num_regs = 1;
        ddata->irq_chip.num_irqs = pdata->num_irqs;

        ddata->irqs = devm_kcalloc(&spi->dev,
                                   pdata->num_irqs, sizeof(struct regmap_irq),
                                   GFP_KERNEL);
        if (!ddata->irqs)
                return -ENOMEM;

        ddata->irq_chip.irqs = ddata->irqs;
        for (i = 0; i < pdata->num_irqs; i++)
                ddata->irqs[i].mask = BIT(i);

        ret = devm_regmap_add_irq_chip(&spi->dev, ddata->regmap, ddata->irq,
                                       IRQF_ONESHOT, 0,
                                       &ddata->irq_chip, &ddata->irq_data);
        if (ret) {
                dev_err(&spi->dev, "Failed to add PMIC irq chip %d\n", ret);
                return ret;
        }

        ret = devm_of_platform_populate(&spi->dev);
        if (ret) {
                dev_err(&spi->dev, "Failed to populate sub-devices %d\n", ret);
                return ret;
        }

        ret = devm_device_init_wakeup(&spi->dev);
        if (ret)
                return dev_err_probe(&spi->dev, ret, "Failed to init wakeup\n");

        return 0;
}

static int sprd_pmic_suspend(struct device *dev)
{
        struct sprd_pmic *ddata = dev_get_drvdata(dev);

        if (device_may_wakeup(dev))
                enable_irq_wake(ddata->irq);

        return 0;
}

static int sprd_pmic_resume(struct device *dev)
{
        struct sprd_pmic *ddata = dev_get_drvdata(dev);

        if (device_may_wakeup(dev))
                disable_irq_wake(ddata->irq);

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(sprd_pmic_pm_ops,
                                sprd_pmic_suspend, sprd_pmic_resume);

static const struct of_device_id sprd_pmic_match[] = {
        { .compatible = "sprd,sc2730", .data = &sc2730_data },
        { .compatible = "sprd,sc2731", .data = &sc2731_data },
        {},
};
MODULE_DEVICE_TABLE(of, sprd_pmic_match);

static const struct spi_device_id sprd_pmic_spi_ids[] = {
        { .name = "sc2730", .driver_data = (unsigned long)&sc2730_data },
        { .name = "sc2731", .driver_data = (unsigned long)&sc2731_data },
        {},
};
MODULE_DEVICE_TABLE(spi, sprd_pmic_spi_ids);

static struct spi_driver sprd_pmic_driver = {
        .driver = {
                .name = "sc27xx-pmic",
                .of_match_table = sprd_pmic_match,
                .pm = pm_sleep_ptr(&sprd_pmic_pm_ops),
        },
        .probe = sprd_pmic_probe,
        .id_table = sprd_pmic_spi_ids,
};

static int __init sprd_pmic_init(void)
{
        return spi_register_driver(&sprd_pmic_driver);
}
subsys_initcall(sprd_pmic_init);

static void __exit sprd_pmic_exit(void)
{
        spi_unregister_driver(&sprd_pmic_driver);
}
module_exit(sprd_pmic_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Spreadtrum SC27xx PMICs driver");
MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");