// SPDX-License-Identifier: GPL-2.0-only
/*
 * MMC5633 - MEMSIC 3-axis Magnetic Sensor
 *
 * Copyright (c) 2015, Intel Corporation.
 * Copyright (c) 2025, NXP
 *
 * IIO driver for MMC5633, base on mmc35240.c
 */

#include <linux/array_size.h>
#include <linux/bitfield.h>
#include <linux/bits.h>
#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dev_printk.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/i3c/device.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/init.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/pm.h>
#include <linux/regmap.h>
#include <linux/time.h>
#include <linux/types.h>
#include <linux/unaligned.h>

#define MMC5633_REG_XOUT0       0x00
#define MMC5633_REG_XOUT1       0x01
#define MMC5633_REG_YOUT0       0x02
#define MMC5633_REG_YOUT1       0x03
#define MMC5633_REG_ZOUT0       0x04
#define MMC5633_REG_ZOUT1       0x05
#define MMC5633_REG_XOUT2       0x06
#define MMC5633_REG_YOUT2       0x07
#define MMC5633_REG_ZOUT2       0x08
#define MMC5633_REG_TOUT        0x09

#define MMC5633_REG_STATUS1     0x18
#define MMC5633_REG_STATUS0     0x19
#define MMC5633_REG_CTRL0       0x1b
#define MMC5633_REG_CTRL1       0x1c
#define MMC5633_REG_CTRL2       0x1d

#define MMC5633_REG_ID          0x39

#define MMC5633_STATUS1_MEAS_T_DONE_BIT BIT(7)
#define MMC5633_STATUS1_MEAS_M_DONE_BIT BIT(6)

#define MMC5633_CTRL0_CMM_FREQ_EN       BIT(7)
#define MMC5633_CTRL0_AUTO_ST_EN        BIT(6)
#define MMC5633_CTRL0_AUTO_SR_EN        BIT(5)
#define MMC5633_CTRL0_RESET             BIT(4)
#define MMC5633_CTRL0_SET               BIT(3)
#define MMC5633_CTRL0_MEAS_T            BIT(1)
#define MMC5633_CTRL0_MEAS_M            BIT(0)

#define MMC5633_CTRL1_BW_MASK           GENMASK(1, 0)

#define MMC5633_WAIT_SET_RESET_US       (1 * USEC_PER_MSEC)

#define MMC5633_HDR_CTRL0_MEAS_M        0x01
#define MMC5633_HDR_CTRL0_MEAS_T        0x03
#define MMC5633_HDR_CTRL0_SET           0x05
#define MMC5633_HDR_CTRL0_RESET         0x07

enum mmc5633_axis {
        MMC5633_AXIS_X,
        MMC5633_AXIS_Y,
        MMC5633_AXIS_Z,
        MMC5633_TEMPERATURE,
};

struct mmc5633_data {
        struct regmap *regmap;
        struct i3c_device *i3cdev;
        struct mutex mutex; /* protect to finish one whole measurement */
};

static int mmc5633_samp_freq[][2] = {
        { 1, 200000 },
        { 2, 0 },
        { 3, 500000 },
        { 6, 600000 },
};

#define MMC5633_CHANNEL(_axis) { \
        .type = IIO_MAGN, \
        .modified = 1, \
        .channel2 = IIO_MOD_ ## _axis, \
        .address = MMC5633_AXIS_ ## _axis, \
        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
                                    BIT(IIO_CHAN_INFO_SCALE), \
}

static const struct iio_chan_spec mmc5633_channels[] = {
        MMC5633_CHANNEL(X),
        MMC5633_CHANNEL(Y),
        MMC5633_CHANNEL(Z),
        {
                .type = IIO_TEMP,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                                      BIT(IIO_CHAN_INFO_SCALE) |
                                      BIT(IIO_CHAN_INFO_OFFSET),
                .address = MMC5633_TEMPERATURE,
        },
};

static int mmc5633_get_samp_freq_index(struct mmc5633_data *data,
                                       int val, int val2)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(mmc5633_samp_freq); i++)
                if (mmc5633_samp_freq[i][0] == val &&
                    mmc5633_samp_freq[i][1] == val2)
                        return i;
        return -EINVAL;
}

static int mmc5633_init(struct mmc5633_data *data)
{
        unsigned int reg_id;
        int ret;

        ret = regmap_read(data->regmap, MMC5633_REG_ID, &reg_id);
        if (ret)
                return dev_err_probe(regmap_get_device(data->regmap), ret,
                                     "Error reading product id\n");

        /*
         * Make sure we restore sensor characteristics, by doing
         * a SET/RESET sequence, the axis polarity being naturally
         * aligned after RESET.
         */
        ret = regmap_write(data->regmap, MMC5633_REG_CTRL0, MMC5633_CTRL0_SET);
        if (ret)
                return ret;

        /*
         * Minimum time interval between SET or RESET to other operations is
         * 1ms according to Operating Timing Diagram in datasheet.
         */
        fsleep(MMC5633_WAIT_SET_RESET_US);

        ret = regmap_write(data->regmap, MMC5633_REG_CTRL0, MMC5633_CTRL0_RESET);
        if (ret)
                return ret;

        /* set default sampling frequency */
        return regmap_update_bits(data->regmap, MMC5633_REG_CTRL1,
                                  MMC5633_CTRL1_BW_MASK,
                                  FIELD_PREP(MMC5633_CTRL1_BW_MASK, 0));
}

static int mmc5633_take_measurement(struct mmc5633_data *data, int address)
{
        unsigned int reg_status, val;
        int ret;

        val = (address == MMC5633_TEMPERATURE) ? MMC5633_CTRL0_MEAS_T : MMC5633_CTRL0_MEAS_M;
        ret = regmap_write(data->regmap, MMC5633_REG_CTRL0, val);
        if (ret < 0)
                return ret;

        val = (address == MMC5633_TEMPERATURE) ?
              MMC5633_STATUS1_MEAS_T_DONE_BIT : MMC5633_STATUS1_MEAS_M_DONE_BIT;
        ret = regmap_read_poll_timeout(data->regmap, MMC5633_REG_STATUS1, reg_status,
                                       reg_status & val,
                                       10 * USEC_PER_MSEC,
                                       100 * 10 * USEC_PER_MSEC);
        if (ret) {
                dev_err(regmap_get_device(data->regmap), "data not ready\n");
                return ret;
        }

        return 0;
}

static bool mmc5633_is_support_hdr(struct mmc5633_data *data)
{
        if (!data->i3cdev)
                return false;

        return i3c_device_get_supported_xfer_mode(data->i3cdev) & BIT(I3C_HDR_DDR);
}

static int mmc5633_read_measurement(struct mmc5633_data *data, int address, void *buf, size_t sz)
{
        struct device *dev = regmap_get_device(data->regmap);
        u8 data_cmd[2], status[2];
        unsigned int val, ready;
        int ret;

        if (mmc5633_is_support_hdr(data)) {
                struct i3c_xfer xfers_wr_cmd[] = {
                        {
                                .cmd = 0x3b,
                                .len = 2,
                                .data.out = data_cmd,
                        }
                };
                struct i3c_xfer xfers_rd_sta_cmd[] = {
                        {
                                .cmd = 0x23 | BIT(7), /* RDSTA CMD */
                                .len = 2,
                                .data.in = status,
                        },
                };
                struct i3c_xfer xfers_rd_data_cmd[] = {
                        {
                                .cmd = 0x22 | BIT(7), /* RDLONG CMD */
                                .len = sz,
                                .data.in = buf,
                        },
                };

                data_cmd[0] = 0;
                data_cmd[1] = (address == MMC5633_TEMPERATURE) ?
                              MMC5633_HDR_CTRL0_MEAS_T : MMC5633_HDR_CTRL0_MEAS_M;

                ret = i3c_device_do_xfers(data->i3cdev, xfers_wr_cmd,
                                          ARRAY_SIZE(xfers_wr_cmd), I3C_HDR_DDR);
                if (ret < 0)
                        return ret;

                ready = (address == MMC5633_TEMPERATURE) ?
                        MMC5633_STATUS1_MEAS_T_DONE_BIT : MMC5633_STATUS1_MEAS_M_DONE_BIT;
                ret = read_poll_timeout(i3c_device_do_xfers, val,
                                        val || (status[0] & ready),
                                        10 * USEC_PER_MSEC,
                                        100 * 10 * USEC_PER_MSEC, 0,
                                        data->i3cdev, xfers_rd_sta_cmd,
                                        ARRAY_SIZE(xfers_rd_sta_cmd), I3C_HDR_DDR);
                if (ret) {
                        dev_err(dev, "data not ready\n");
                        return ret;
                }
                if (val) {
                        dev_err(dev, "i3c transfer error\n");
                        return val;
                }
                return i3c_device_do_xfers(data->i3cdev, xfers_rd_data_cmd,
                                           ARRAY_SIZE(xfers_rd_data_cmd), I3C_HDR_DDR);
        }

        /* Fallback to use SDR/I2C mode */
        ret = mmc5633_take_measurement(data, address);
        if (ret < 0)
                return ret;

        if (address == MMC5633_TEMPERATURE)
                /*
                 * Put tempeature to last byte of buff to align HDR case.
                 * I3C will early terminate data read if previous data is not
                 * available.
                 */
                return regmap_bulk_read(data->regmap, MMC5633_REG_TOUT, buf + sz - 1, 1);

        return regmap_bulk_read(data->regmap, MMC5633_REG_XOUT0, buf, sz);
}

/* X,Y,Z 3 channels, each channel has 3 byte and TEMP */
#define MMC5633_ALL_SIZE (3 * 3 + 1)

static int mmc5633_get_raw(struct mmc5633_data *data, int index, unsigned char *buf, int *val)
{
        if (index == MMC5633_TEMPERATURE) {
                *val = buf[MMC5633_ALL_SIZE - 1];
                return 0;
        }
        /*
         * X[19..12] X[11..4] Y[19..12] Y[11..4] Z[19..12] Z[11..4] X[3..0] Y[3..0] Z[3..0]
         */
        *val = get_unaligned_be16(buf + 2 * index) << 4;
        *val |= buf[index + 6] >> 4;

        return 0;
}

static int mmc5633_read_raw(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan, int *val,
                            int *val2, long mask)
{
        struct mmc5633_data *data = iio_priv(indio_dev);
        char buf[MMC5633_ALL_SIZE];
        unsigned int reg, i;
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                scoped_guard(mutex, &data->mutex) {
                        ret = mmc5633_read_measurement(data, chan->address, buf, MMC5633_ALL_SIZE);
                        if (ret < 0)
                                return ret;
                }

                ret = mmc5633_get_raw(data, chan->address, buf, val);
                if (ret < 0)
                        return ret;
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                if (chan->type == IIO_MAGN) {
                        *val = 0;
                        *val2 = 62500;
                } else {
                        *val = 0;
                        *val2 = 800000000; /* 0.8C */
                }
                return IIO_VAL_INT_PLUS_NANO;
        case IIO_CHAN_INFO_OFFSET:
                if (chan->type == IIO_TEMP) {
                        *val = -75;
                        return IIO_VAL_INT;
                }
                return -EINVAL;
        case IIO_CHAN_INFO_SAMP_FREQ:
                scoped_guard(mutex, &data->mutex) {
                        ret = regmap_read(data->regmap, MMC5633_REG_CTRL1, &reg);
                        if (ret < 0)
                                return ret;
                }

                i = FIELD_GET(MMC5633_CTRL1_BW_MASK, reg);
                if (i >= ARRAY_SIZE(mmc5633_samp_freq))
                        return -EINVAL;

                *val = mmc5633_samp_freq[i][0];
                *val2 = mmc5633_samp_freq[i][1];
                return IIO_VAL_INT_PLUS_MICRO;
        default:
                return -EINVAL;
        }
}

static int mmc5633_write_raw(struct iio_dev *indio_dev,
                             struct iio_chan_spec const *chan, int val,
                             int val2, long mask)
{
        struct mmc5633_data *data = iio_priv(indio_dev);
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_SAMP_FREQ: {
                ret = mmc5633_get_samp_freq_index(data, val, val2);
                if (ret < 0)
                        return ret;

                guard(mutex)(&data->mutex);

                return regmap_update_bits(data->regmap, MMC5633_REG_CTRL1,
                                          MMC5633_CTRL1_BW_MASK,
                                          FIELD_PREP(MMC5633_CTRL1_BW_MASK, ret));
        }
        default:
                return -EINVAL;
        }
}

static int mmc5633_read_avail(struct iio_dev *indio_dev,
                              struct iio_chan_spec const *chan,
                              const int **vals, int *type, int *length,
                              long mask)
{
        switch (mask) {
        case IIO_CHAN_INFO_SAMP_FREQ:
                *vals = (const int *)mmc5633_samp_freq;
                *length = ARRAY_SIZE(mmc5633_samp_freq) * 2;
                *type = IIO_VAL_INT_PLUS_MICRO;
                return IIO_AVAIL_LIST;
        default:
                return -EINVAL;
        }
}

static const struct iio_info mmc5633_info = {
        .read_raw       = mmc5633_read_raw,
        .write_raw      = mmc5633_write_raw,
        .read_avail     = mmc5633_read_avail,
};

static bool mmc5633_is_writeable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MMC5633_REG_CTRL0:
        case MMC5633_REG_CTRL1:
                return true;
        default:
                return false;
        }
}

static bool mmc5633_is_readable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MMC5633_REG_XOUT0:
        case MMC5633_REG_XOUT1:
        case MMC5633_REG_YOUT0:
        case MMC5633_REG_YOUT1:
        case MMC5633_REG_ZOUT0:
        case MMC5633_REG_ZOUT1:
        case MMC5633_REG_XOUT2:
        case MMC5633_REG_YOUT2:
        case MMC5633_REG_ZOUT2:
        case MMC5633_REG_TOUT:
        case MMC5633_REG_STATUS1:
        case MMC5633_REG_ID:
                return true;
        default:
                return false;
        }
}

static bool mmc5633_is_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case MMC5633_REG_CTRL0:
        case MMC5633_REG_CTRL1:
                return false;
        default:
                return true;
        }
}

static const struct reg_default mmc5633_reg_defaults[] = {
        { MMC5633_REG_CTRL0,  0x00 },
        { MMC5633_REG_CTRL1,  0x00 },
};

static const struct regmap_config mmc5633_regmap_config = {
        .name = "mmc5633_regmap",

        .reg_bits = 8,
        .val_bits = 8,

        .max_register = MMC5633_REG_ID,
        .cache_type = REGCACHE_MAPLE,

        .writeable_reg = mmc5633_is_writeable_reg,
        .readable_reg = mmc5633_is_readable_reg,
        .volatile_reg = mmc5633_is_volatile_reg,

        .reg_defaults = mmc5633_reg_defaults,
        .num_reg_defaults = ARRAY_SIZE(mmc5633_reg_defaults),
};

static int mmc5633_common_probe(struct regmap *regmap, char *name,
                                struct i3c_device *i3cdev)
{
        struct device *dev = regmap_get_device(regmap);
        struct mmc5633_data *data;
        struct iio_dev *indio_dev;
        int ret;

        indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
        if (!indio_dev)
                return -ENOMEM;

        data = iio_priv(indio_dev);

        data->regmap = regmap;
        data->i3cdev = i3cdev;

        ret = devm_mutex_init(dev, &data->mutex);
        if (ret)
                return ret;

        indio_dev->info = &mmc5633_info;
        indio_dev->name = name;
        indio_dev->channels = mmc5633_channels;
        indio_dev->num_channels = ARRAY_SIZE(mmc5633_channels);
        indio_dev->modes = INDIO_DIRECT_MODE;

        ret = mmc5633_init(data);
        if (ret < 0)
                return dev_err_probe(dev, ret, "mmc5633 chip init failed\n");

        return devm_iio_device_register(dev, indio_dev);
}

static int mmc5633_suspend(struct device *dev)
{
        struct regmap *regmap = dev_get_regmap(dev, NULL);

        regcache_cache_only(regmap, true);

        return 0;
}

static int mmc5633_resume(struct device *dev)
{
        struct regmap *regmap = dev_get_regmap(dev, NULL);
        int ret;

        regcache_mark_dirty(regmap);
        ret = regcache_sync_region(regmap, MMC5633_REG_CTRL0, MMC5633_REG_CTRL1);
        if (ret)
                dev_err(dev, "Failed to restore control registers\n");

        regcache_cache_only(regmap, false);

        return 0;
}

static int mmc5633_i2c_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct regmap *regmap;

        regmap = devm_regmap_init_i2c(client, &mmc5633_regmap_config);
        if (IS_ERR(regmap))
                return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed\n");

        return mmc5633_common_probe(regmap, client->name, NULL);
}

static DEFINE_SIMPLE_DEV_PM_OPS(mmc5633_pm_ops, mmc5633_suspend, mmc5633_resume);

static const struct of_device_id mmc5633_of_match[] = {
        { .compatible = "memsic,mmc5603" },
        { .compatible = "memsic,mmc5633" },
        { }
};
MODULE_DEVICE_TABLE(of, mmc5633_of_match);

static const struct i2c_device_id mmc5633_i2c_id[] = {
        { "mmc5603" },
        { "mmc5633" },
        { }
};
MODULE_DEVICE_TABLE(i2c, mmc5633_i2c_id);

static struct i2c_driver mmc5633_i2c_driver = {
        .driver = {
                .name = "mmc5633_i2c",
                .of_match_table = mmc5633_of_match,
                .pm = pm_sleep_ptr(&mmc5633_pm_ops),
        },
        .probe = mmc5633_i2c_probe,
        .id_table = mmc5633_i2c_id,
};

static const struct i3c_device_id mmc5633_i3c_ids[] = {
        I3C_DEVICE(0x0251, 0x0000, NULL),
        { }
};
MODULE_DEVICE_TABLE(i3c, mmc5633_i3c_ids);

static int mmc5633_i3c_probe(struct i3c_device *i3cdev)
{
        struct device *dev = i3cdev_to_dev(i3cdev);
        struct regmap *regmap;
        char *name;

        name = devm_kasprintf(dev, GFP_KERNEL, "mmc5633_%s", dev_name(dev));
        if (!name)
                return -ENOMEM;

        regmap = devm_regmap_init_i3c(i3cdev, &mmc5633_regmap_config);
        if (IS_ERR(regmap))
                return dev_err_probe(dev, PTR_ERR(regmap),
                                     "Failed to register i3c regmap\n");

        return mmc5633_common_probe(regmap, name, i3cdev);
}

static struct i3c_driver mmc5633_i3c_driver = {
        .driver = {
                .name = "mmc5633_i3c",
        },
        .probe = mmc5633_i3c_probe,
        .id_table = mmc5633_i3c_ids,
};
module_i3c_i2c_driver(mmc5633_i3c_driver, &mmc5633_i2c_driver)

MODULE_AUTHOR("Frank Li <Frank.li@nxp.com>");
MODULE_DESCRIPTION("MEMSIC MMC5633 magnetic sensor driver");
MODULE_LICENSE("GPL");