// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2020 Invensense, Inc.
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/delay.h>
#include <linux/math64.h>

#include <linux/iio/buffer.h>
#include <linux/iio/common/inv_sensors_timestamp.h>
#include <linux/iio/iio.h>
#include <linux/iio/kfifo_buf.h>

#include "inv_icm42600.h"
#include "inv_icm42600_temp.h"
#include "inv_icm42600_buffer.h"

#define INV_ICM42600_GYRO_CHAN(_modifier, _index, _ext_info)            \
        {                                                               \
                .type = IIO_ANGL_VEL,                                   \
                .modified = 1,                                          \
                .channel2 = _modifier,                                  \
                .info_mask_separate =                                   \
                        BIT(IIO_CHAN_INFO_RAW) |                        \
                        BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
                .info_mask_shared_by_type =                             \
                        BIT(IIO_CHAN_INFO_SCALE),                       \
                .info_mask_shared_by_type_available =                   \
                        BIT(IIO_CHAN_INFO_SCALE) |                      \
                        BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
                .info_mask_shared_by_all =                              \
                        BIT(IIO_CHAN_INFO_SAMP_FREQ),                   \
                .info_mask_shared_by_all_available =                    \
                        BIT(IIO_CHAN_INFO_SAMP_FREQ),                   \
                .scan_index = _index,                                   \
                .scan_type = {                                          \
                        .sign = 's',                                    \
                        .realbits = 16,                                 \
                        .storagebits = 16,                              \
                        .endianness = IIO_BE,                           \
                },                                                      \
                .ext_info = _ext_info,                                  \
        }

enum inv_icm42600_gyro_scan {
        INV_ICM42600_GYRO_SCAN_X,
        INV_ICM42600_GYRO_SCAN_Y,
        INV_ICM42600_GYRO_SCAN_Z,
        INV_ICM42600_GYRO_SCAN_TEMP,
        INV_ICM42600_GYRO_SCAN_TIMESTAMP,
};

static const struct iio_chan_spec_ext_info inv_icm42600_gyro_ext_infos[] = {
        IIO_MOUNT_MATRIX(IIO_SHARED_BY_ALL, inv_icm42600_get_mount_matrix),
        { }
};

static const struct iio_chan_spec inv_icm42600_gyro_channels[] = {
        INV_ICM42600_GYRO_CHAN(IIO_MOD_X, INV_ICM42600_GYRO_SCAN_X,
                               inv_icm42600_gyro_ext_infos),
        INV_ICM42600_GYRO_CHAN(IIO_MOD_Y, INV_ICM42600_GYRO_SCAN_Y,
                               inv_icm42600_gyro_ext_infos),
        INV_ICM42600_GYRO_CHAN(IIO_MOD_Z, INV_ICM42600_GYRO_SCAN_Z,
                               inv_icm42600_gyro_ext_infos),
        INV_ICM42600_TEMP_CHAN(INV_ICM42600_GYRO_SCAN_TEMP),
        IIO_CHAN_SOFT_TIMESTAMP(INV_ICM42600_GYRO_SCAN_TIMESTAMP),
};

/*
 * IIO buffer data: size must be a power of 2 and timestamp aligned
 * 16 bytes: 6 bytes angular velocity, 2 bytes temperature, 8 bytes timestamp
 */
struct inv_icm42600_gyro_buffer {
        struct inv_icm42600_fifo_sensor_data gyro;
        s16 temp;
        aligned_s64 timestamp;
};

#define INV_ICM42600_SCAN_MASK_GYRO_3AXIS                               \
        (BIT(INV_ICM42600_GYRO_SCAN_X) |                                \
        BIT(INV_ICM42600_GYRO_SCAN_Y) |                                 \
        BIT(INV_ICM42600_GYRO_SCAN_Z))

#define INV_ICM42600_SCAN_MASK_TEMP     BIT(INV_ICM42600_GYRO_SCAN_TEMP)

static const unsigned long inv_icm42600_gyro_scan_masks[] = {
        /* 3-axis gyro + temperature */
        INV_ICM42600_SCAN_MASK_GYRO_3AXIS | INV_ICM42600_SCAN_MASK_TEMP,
        0,
};

/* enable gyroscope sensor and FIFO write */
static int inv_icm42600_gyro_update_scan_mode(struct iio_dev *indio_dev,
                                              const unsigned long *scan_mask)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
        unsigned int fifo_en = 0;
        unsigned int sleep_gyro = 0;
        unsigned int sleep_temp = 0;
        unsigned int sleep;
        int ret;

        mutex_lock(&st->lock);

        if (*scan_mask & INV_ICM42600_SCAN_MASK_TEMP) {
                /* enable temp sensor */
                ret = inv_icm42600_set_temp_conf(st, true, &sleep_temp);
                if (ret)
                        goto out_unlock;
                fifo_en |= INV_ICM42600_SENSOR_TEMP;
        }

        if (*scan_mask & INV_ICM42600_SCAN_MASK_GYRO_3AXIS) {
                /* enable gyro sensor */
                conf.mode = INV_ICM42600_SENSOR_MODE_LOW_NOISE;
                ret = inv_icm42600_set_gyro_conf(st, &conf, &sleep_gyro);
                if (ret)
                        goto out_unlock;
                fifo_en |= INV_ICM42600_SENSOR_GYRO;
        }

        /* update data FIFO write */
        ret = inv_icm42600_buffer_set_fifo_en(st, fifo_en | st->fifo.en);

out_unlock:
        mutex_unlock(&st->lock);
        /* sleep maximum required time */
        sleep = max(sleep_gyro, sleep_temp);
        if (sleep)
                msleep(sleep);
        return ret;
}

static int inv_icm42600_gyro_read_sensor(struct inv_icm42600_state *st,
                                         struct iio_chan_spec const *chan,
                                         s16 *val)
{
        struct device *dev = regmap_get_device(st->map);
        struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
        unsigned int reg;
        __be16 *data;
        int ret;

        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (chan->channel2) {
        case IIO_MOD_X:
                reg = INV_ICM42600_REG_GYRO_DATA_X;
                break;
        case IIO_MOD_Y:
                reg = INV_ICM42600_REG_GYRO_DATA_Y;
                break;
        case IIO_MOD_Z:
                reg = INV_ICM42600_REG_GYRO_DATA_Z;
                break;
        default:
                return -EINVAL;
        }

        pm_runtime_get_sync(dev);
        mutex_lock(&st->lock);

        /* enable gyro sensor */
        conf.mode = INV_ICM42600_SENSOR_MODE_LOW_NOISE;
        ret = inv_icm42600_set_gyro_conf(st, &conf, NULL);
        if (ret)
                goto exit;

        /* read gyro register data */
        data = (__be16 *)&st->buffer[0];
        ret = regmap_bulk_read(st->map, reg, data, sizeof(*data));
        if (ret)
                goto exit;

        *val = (s16)be16_to_cpup(data);
        if (*val == INV_ICM42600_DATA_INVALID)
                ret = -EINVAL;
exit:
        mutex_unlock(&st->lock);
        pm_runtime_put_autosuspend(dev);
        return ret;
}

/* IIO format int + nano */
static const int inv_icm42600_gyro_scale[] = {
        /* +/- 2000dps => 0.001065264 rad/s */
        [2 * INV_ICM42600_GYRO_FS_2000DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_2000DPS + 1] = 1065264,
        /* +/- 1000dps => 0.000532632 rad/s */
        [2 * INV_ICM42600_GYRO_FS_1000DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_1000DPS + 1] = 532632,
        /* +/- 500dps => 0.000266316 rad/s */
        [2 * INV_ICM42600_GYRO_FS_500DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_500DPS + 1] = 266316,
        /* +/- 250dps => 0.000133158 rad/s */
        [2 * INV_ICM42600_GYRO_FS_250DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_250DPS + 1] = 133158,
        /* +/- 125dps => 0.000066579 rad/s */
        [2 * INV_ICM42600_GYRO_FS_125DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_125DPS + 1] = 66579,
        /* +/- 62.5dps => 0.000033290 rad/s */
        [2 * INV_ICM42600_GYRO_FS_62_5DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_62_5DPS + 1] = 33290,
        /* +/- 31.25dps => 0.000016645 rad/s */
        [2 * INV_ICM42600_GYRO_FS_31_25DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_31_25DPS + 1] = 16645,
        /* +/- 15.625dps => 0.000008322 rad/s */
        [2 * INV_ICM42600_GYRO_FS_15_625DPS] = 0,
        [2 * INV_ICM42600_GYRO_FS_15_625DPS + 1] = 8322,
};
static const int inv_icm42686_gyro_scale[] = {
        /* +/- 4000dps => 0.002130529 rad/s */
        [2 * INV_ICM42686_GYRO_FS_4000DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_4000DPS + 1] = 2130529,
        /* +/- 2000dps => 0.001065264 rad/s */
        [2 * INV_ICM42686_GYRO_FS_2000DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_2000DPS + 1] = 1065264,
        /* +/- 1000dps => 0.000532632 rad/s */
        [2 * INV_ICM42686_GYRO_FS_1000DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_1000DPS + 1] = 532632,
        /* +/- 500dps => 0.000266316 rad/s */
        [2 * INV_ICM42686_GYRO_FS_500DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_500DPS + 1] = 266316,
        /* +/- 250dps => 0.000133158 rad/s */
        [2 * INV_ICM42686_GYRO_FS_250DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_250DPS + 1] = 133158,
        /* +/- 125dps => 0.000066579 rad/s */
        [2 * INV_ICM42686_GYRO_FS_125DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_125DPS + 1] = 66579,
        /* +/- 62.5dps => 0.000033290 rad/s */
        [2 * INV_ICM42686_GYRO_FS_62_5DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_62_5DPS + 1] = 33290,
        /* +/- 31.25dps => 0.000016645 rad/s */
        [2 * INV_ICM42686_GYRO_FS_31_25DPS] = 0,
        [2 * INV_ICM42686_GYRO_FS_31_25DPS + 1] = 16645,
};

static int inv_icm42600_gyro_read_scale(struct iio_dev *indio_dev,
                                        int *val, int *val2)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        struct inv_icm42600_sensor_state *gyro_st = iio_priv(indio_dev);
        unsigned int idx;

        idx = st->conf.gyro.fs;

        *val = gyro_st->scales[2 * idx];
        *val2 = gyro_st->scales[2 * idx + 1];
        return IIO_VAL_INT_PLUS_NANO;
}

static int inv_icm42600_gyro_write_scale(struct iio_dev *indio_dev,
                                         int val, int val2)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        struct inv_icm42600_sensor_state *gyro_st = iio_priv(indio_dev);
        struct device *dev = regmap_get_device(st->map);
        unsigned int idx;
        struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
        int ret;

        for (idx = 0; idx < gyro_st->scales_len; idx += 2) {
                if (val == gyro_st->scales[idx] &&
                    val2 == gyro_st->scales[idx + 1])
                        break;
        }
        if (idx >= gyro_st->scales_len)
                return -EINVAL;

        conf.fs = idx / 2;

        pm_runtime_get_sync(dev);

        scoped_guard(mutex, &st->lock)
                ret = inv_icm42600_set_gyro_conf(st, &conf, NULL);

        pm_runtime_put_autosuspend(dev);

        return ret;
}

/* IIO format int + micro */
static const int inv_icm42600_gyro_odr[] = {
        /* 12.5Hz */
        12, 500000,
        /* 25Hz */
        25, 0,
        /* 50Hz */
        50, 0,
        /* 100Hz */
        100, 0,
        /* 200Hz */
        200, 0,
        /* 1kHz */
        1000, 0,
        /* 2kHz */
        2000, 0,
        /* 4kHz */
        4000, 0,
};

static const int inv_icm42600_gyro_odr_conv[] = {
        INV_ICM42600_ODR_12_5HZ,
        INV_ICM42600_ODR_25HZ,
        INV_ICM42600_ODR_50HZ,
        INV_ICM42600_ODR_100HZ,
        INV_ICM42600_ODR_200HZ,
        INV_ICM42600_ODR_1KHZ_LN,
        INV_ICM42600_ODR_2KHZ_LN,
        INV_ICM42600_ODR_4KHZ_LN,
};

static int inv_icm42600_gyro_read_odr(struct inv_icm42600_state *st,
                                      int *val, int *val2)
{
        unsigned int odr;
        unsigned int i;

        odr = st->conf.gyro.odr;

        for (i = 0; i < ARRAY_SIZE(inv_icm42600_gyro_odr_conv); ++i) {
                if (inv_icm42600_gyro_odr_conv[i] == odr)
                        break;
        }
        if (i >= ARRAY_SIZE(inv_icm42600_gyro_odr_conv))
                return -EINVAL;

        *val = inv_icm42600_gyro_odr[2 * i];
        *val2 = inv_icm42600_gyro_odr[2 * i + 1];

        return IIO_VAL_INT_PLUS_MICRO;
}

static int inv_icm42600_gyro_write_odr(struct iio_dev *indio_dev,
                                       int val, int val2)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        struct inv_icm42600_sensor_state *gyro_st = iio_priv(indio_dev);
        struct inv_sensors_timestamp *ts = &gyro_st->ts;
        struct device *dev = regmap_get_device(st->map);
        unsigned int idx;
        struct inv_icm42600_sensor_conf conf = INV_ICM42600_SENSOR_CONF_INIT;
        int ret;

        for (idx = 0; idx < ARRAY_SIZE(inv_icm42600_gyro_odr); idx += 2) {
                if (val == inv_icm42600_gyro_odr[idx] &&
                    val2 == inv_icm42600_gyro_odr[idx + 1])
                        break;
        }
        if (idx >= ARRAY_SIZE(inv_icm42600_gyro_odr))
                return -EINVAL;

        conf.odr = inv_icm42600_gyro_odr_conv[idx / 2];
        if (conf.odr == st->conf.gyro.odr)
                return 0;

        pm_runtime_get_sync(dev);
        mutex_lock(&st->lock);

        ret = inv_sensors_timestamp_update_odr(ts, inv_icm42600_odr_to_period(conf.odr),
                                               iio_buffer_enabled(indio_dev));
        if (ret)
                goto out_unlock;

        ret = inv_icm42600_set_gyro_conf(st, &conf, NULL);
        if (ret)
                goto out_unlock;
        inv_icm42600_buffer_update_fifo_period(st);
        inv_icm42600_buffer_update_watermark(st);

out_unlock:
        mutex_unlock(&st->lock);
        pm_runtime_put_autosuspend(dev);

        return ret;
}

/*
 * Calibration bias values, IIO range format int + nano.
 * Value is limited to +/-64dps coded on 12 bits signed. Step is 1/32 dps.
 */
static int inv_icm42600_gyro_calibbias[] = {
        -1, 117010721,          /* min: -1.117010721 rad/s */
        0, 545415,              /* step: 0.000545415 rad/s */
        1, 116465306,           /* max: 1.116465306 rad/s */
};

static int inv_icm42600_gyro_read_offset(struct inv_icm42600_state *st,
                                         struct iio_chan_spec const *chan,
                                         int *val, int *val2)
{
        struct device *dev = regmap_get_device(st->map);
        s64 val64;
        s32 bias;
        unsigned int reg;
        s16 offset;
        u8 data[2];
        int ret;

        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (chan->channel2) {
        case IIO_MOD_X:
                reg = INV_ICM42600_REG_OFFSET_USER0;
                break;
        case IIO_MOD_Y:
                reg = INV_ICM42600_REG_OFFSET_USER1;
                break;
        case IIO_MOD_Z:
                reg = INV_ICM42600_REG_OFFSET_USER3;
                break;
        default:
                return -EINVAL;
        }

        pm_runtime_get_sync(dev);
        mutex_lock(&st->lock);

        ret = regmap_bulk_read(st->map, reg, st->buffer, sizeof(data));
        memcpy(data, st->buffer, sizeof(data));

        mutex_unlock(&st->lock);
        pm_runtime_put_autosuspend(dev);
        if (ret)
                return ret;

        /* 12 bits signed value */
        switch (chan->channel2) {
        case IIO_MOD_X:
                offset = sign_extend32(((data[1] & 0x0F) << 8) | data[0], 11);
                break;
        case IIO_MOD_Y:
                offset = sign_extend32(((data[0] & 0xF0) << 4) | data[1], 11);
                break;
        case IIO_MOD_Z:
                offset = sign_extend32(((data[1] & 0x0F) << 8) | data[0], 11);
                break;
        default:
                return -EINVAL;
        }

        /*
         * convert raw offset to dps then to rad/s
         * 12 bits signed raw max 64 to dps: 64 / 2048
         * dps to rad: Pi / 180
         * result in nano (1000000000)
         * (offset * 64 * Pi * 1000000000) / (2048 * 180)
         */
        val64 = (s64)offset * 64LL * 3141592653LL;
        /* for rounding, add + or - divisor (2048 * 180) divided by 2 */
        if (val64 >= 0)
                val64 += 2048 * 180 / 2;
        else
                val64 -= 2048 * 180 / 2;
        bias = div_s64(val64, 2048 * 180);
        *val = bias / 1000000000L;
        *val2 = bias % 1000000000L;

        return IIO_VAL_INT_PLUS_NANO;
}

static int inv_icm42600_gyro_write_offset(struct inv_icm42600_state *st,
                                          struct iio_chan_spec const *chan,
                                          int val, int val2)
{
        struct device *dev = regmap_get_device(st->map);
        s64 val64, min, max;
        unsigned int reg, regval;
        s16 offset;
        int ret;

        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (chan->channel2) {
        case IIO_MOD_X:
                reg = INV_ICM42600_REG_OFFSET_USER0;
                break;
        case IIO_MOD_Y:
                reg = INV_ICM42600_REG_OFFSET_USER1;
                break;
        case IIO_MOD_Z:
                reg = INV_ICM42600_REG_OFFSET_USER3;
                break;
        default:
                return -EINVAL;
        }

        /* inv_icm42600_gyro_calibbias: min - step - max in nano */
        min = (s64)inv_icm42600_gyro_calibbias[0] * 1000000000LL +
              (s64)inv_icm42600_gyro_calibbias[1];
        max = (s64)inv_icm42600_gyro_calibbias[4] * 1000000000LL +
              (s64)inv_icm42600_gyro_calibbias[5];
        val64 = (s64)val * 1000000000LL + (s64)val2;
        if (val64 < min || val64 > max)
                return -EINVAL;

        /*
         * convert rad/s to dps then to raw value
         * rad to dps: 180 / Pi
         * dps to raw 12 bits signed, max 64: 2048 / 64
         * val in nano (1000000000)
         * val * 180 * 2048 / (Pi * 1000000000 * 64)
         */
        val64 = val64 * 180LL * 2048LL;
        /* for rounding, add + or - divisor (3141592653 * 64) divided by 2 */
        if (val64 >= 0)
                val64 += 3141592653LL * 64LL / 2LL;
        else
                val64 -= 3141592653LL * 64LL / 2LL;
        offset = div64_s64(val64, 3141592653LL * 64LL);

        /* clamp value limited to 12 bits signed */
        if (offset < -2048)
                offset = -2048;
        else if (offset > 2047)
                offset = 2047;

        pm_runtime_get_sync(dev);
        mutex_lock(&st->lock);

        switch (chan->channel2) {
        case IIO_MOD_X:
                /* OFFSET_USER1 register is shared */
                ret = regmap_read(st->map, INV_ICM42600_REG_OFFSET_USER1,
                                  &regval);
                if (ret)
                        goto out_unlock;
                st->buffer[0] = offset & 0xFF;
                st->buffer[1] = (regval & 0xF0) | ((offset & 0xF00) >> 8);
                break;
        case IIO_MOD_Y:
                /* OFFSET_USER1 register is shared */
                ret = regmap_read(st->map, INV_ICM42600_REG_OFFSET_USER1,
                                  &regval);
                if (ret)
                        goto out_unlock;
                st->buffer[0] = ((offset & 0xF00) >> 4) | (regval & 0x0F);
                st->buffer[1] = offset & 0xFF;
                break;
        case IIO_MOD_Z:
                /* OFFSET_USER4 register is shared */
                ret = regmap_read(st->map, INV_ICM42600_REG_OFFSET_USER4,
                                  &regval);
                if (ret)
                        goto out_unlock;
                st->buffer[0] = offset & 0xFF;
                st->buffer[1] = (regval & 0xF0) | ((offset & 0xF00) >> 8);
                break;
        default:
                ret = -EINVAL;
                goto out_unlock;
        }

        ret = regmap_bulk_write(st->map, reg, st->buffer, 2);

out_unlock:
        mutex_unlock(&st->lock);
        pm_runtime_put_autosuspend(dev);
        return ret;
}

static int inv_icm42600_gyro_read_raw(struct iio_dev *indio_dev,
                                      struct iio_chan_spec const *chan,
                                      int *val, int *val2, long mask)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        s16 data;
        int ret;

        switch (chan->type) {
        case IIO_ANGL_VEL:
                break;
        case IIO_TEMP:
                return inv_icm42600_temp_read_raw(indio_dev, chan, val, val2, mask);
        default:
                return -EINVAL;
        }

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (!iio_device_claim_direct(indio_dev))
                        return -EBUSY;
                ret = inv_icm42600_gyro_read_sensor(st, chan, &data);
                iio_device_release_direct(indio_dev);
                if (ret)
                        return ret;
                *val = data;
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                return inv_icm42600_gyro_read_scale(indio_dev, val, val2);
        case IIO_CHAN_INFO_SAMP_FREQ:
                return inv_icm42600_gyro_read_odr(st, val, val2);
        case IIO_CHAN_INFO_CALIBBIAS:
                return inv_icm42600_gyro_read_offset(st, chan, val, val2);
        default:
                return -EINVAL;
        }
}

static int inv_icm42600_gyro_read_avail(struct iio_dev *indio_dev,
                                        struct iio_chan_spec const *chan,
                                        const int **vals,
                                        int *type, int *length, long mask)
{
        struct inv_icm42600_sensor_state *gyro_st = iio_priv(indio_dev);

        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (mask) {
        case IIO_CHAN_INFO_SCALE:
                *vals = gyro_st->scales;
                *type = IIO_VAL_INT_PLUS_NANO;
                *length = gyro_st->scales_len;
                return IIO_AVAIL_LIST;
        case IIO_CHAN_INFO_SAMP_FREQ:
                *vals = inv_icm42600_gyro_odr;
                *type = IIO_VAL_INT_PLUS_MICRO;
                *length = ARRAY_SIZE(inv_icm42600_gyro_odr);
                return IIO_AVAIL_LIST;
        case IIO_CHAN_INFO_CALIBBIAS:
                *vals = inv_icm42600_gyro_calibbias;
                *type = IIO_VAL_INT_PLUS_NANO;
                return IIO_AVAIL_RANGE;
        default:
                return -EINVAL;
        }
}

static int inv_icm42600_gyro_write_raw(struct iio_dev *indio_dev,
                                       struct iio_chan_spec const *chan,
                                       int val, int val2, long mask)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        int ret;

        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (mask) {
        case IIO_CHAN_INFO_SCALE:
                if (!iio_device_claim_direct(indio_dev))
                        return -EBUSY;
                ret = inv_icm42600_gyro_write_scale(indio_dev, val, val2);
                iio_device_release_direct(indio_dev);
                return ret;
        case IIO_CHAN_INFO_SAMP_FREQ:
                return inv_icm42600_gyro_write_odr(indio_dev, val, val2);
        case IIO_CHAN_INFO_CALIBBIAS:
                if (!iio_device_claim_direct(indio_dev))
                        return -EBUSY;
                ret = inv_icm42600_gyro_write_offset(st, chan, val, val2);
                iio_device_release_direct(indio_dev);
                return ret;
        default:
                return -EINVAL;
        }
}

static int inv_icm42600_gyro_write_raw_get_fmt(struct iio_dev *indio_dev,
                                               struct iio_chan_spec const *chan,
                                               long mask)
{
        if (chan->type != IIO_ANGL_VEL)
                return -EINVAL;

        switch (mask) {
        case IIO_CHAN_INFO_SCALE:
                return IIO_VAL_INT_PLUS_NANO;
        case IIO_CHAN_INFO_SAMP_FREQ:
                return IIO_VAL_INT_PLUS_MICRO;
        case IIO_CHAN_INFO_CALIBBIAS:
                return IIO_VAL_INT_PLUS_NANO;
        default:
                return -EINVAL;
        }
}

static int inv_icm42600_gyro_hwfifo_set_watermark(struct iio_dev *indio_dev,
                                                  unsigned int val)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);

        guard(mutex)(&st->lock);

        st->fifo.watermark.gyro = val;
        return inv_icm42600_buffer_update_watermark(st);
}

static int inv_icm42600_gyro_hwfifo_flush(struct iio_dev *indio_dev,
                                          unsigned int count)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        int ret;

        if (count == 0)
                return 0;

        guard(mutex)(&st->lock);

        ret = inv_icm42600_buffer_hwfifo_flush(st, count);
        if (ret)
                return ret;

        return st->fifo.nb.gyro;
}

static const struct iio_info inv_icm42600_gyro_info = {
        .read_raw = inv_icm42600_gyro_read_raw,
        .read_avail = inv_icm42600_gyro_read_avail,
        .write_raw = inv_icm42600_gyro_write_raw,
        .write_raw_get_fmt = inv_icm42600_gyro_write_raw_get_fmt,
        .debugfs_reg_access = inv_icm42600_debugfs_reg,
        .update_scan_mode = inv_icm42600_gyro_update_scan_mode,
        .hwfifo_set_watermark = inv_icm42600_gyro_hwfifo_set_watermark,
        .hwfifo_flush_to_buffer = inv_icm42600_gyro_hwfifo_flush,
};

struct iio_dev *inv_icm42600_gyro_init(struct inv_icm42600_state *st)
{
        struct device *dev = regmap_get_device(st->map);
        const char *name;
        struct inv_icm42600_sensor_state *gyro_st;
        struct inv_sensors_timestamp_chip ts_chip;
        struct iio_dev *indio_dev;
        int ret;

        name = devm_kasprintf(dev, GFP_KERNEL, "%s-gyro", st->name);
        if (!name)
                return ERR_PTR(-ENOMEM);

        indio_dev = devm_iio_device_alloc(dev, sizeof(*gyro_st));
        if (!indio_dev)
                return ERR_PTR(-ENOMEM);
        gyro_st = iio_priv(indio_dev);

        switch (st->chip) {
        case INV_CHIP_ICM42686:
                gyro_st->scales = inv_icm42686_gyro_scale;
                gyro_st->scales_len = ARRAY_SIZE(inv_icm42686_gyro_scale);
                break;
        default:
                gyro_st->scales = inv_icm42600_gyro_scale;
                gyro_st->scales_len = ARRAY_SIZE(inv_icm42600_gyro_scale);
                break;
        }

        /*
         * clock period is 32kHz (31250ns)
         * jitter is +/- 2% (20 per mille)
         */
        ts_chip.clock_period = 31250;
        ts_chip.jitter = 20;
        ts_chip.init_period = inv_icm42600_odr_to_period(st->conf.accel.odr);
        inv_sensors_timestamp_init(&gyro_st->ts, &ts_chip);

        iio_device_set_drvdata(indio_dev, st);
        indio_dev->name = name;
        indio_dev->info = &inv_icm42600_gyro_info;
        indio_dev->modes = INDIO_DIRECT_MODE;
        indio_dev->channels = inv_icm42600_gyro_channels;
        indio_dev->num_channels = ARRAY_SIZE(inv_icm42600_gyro_channels);
        indio_dev->available_scan_masks = inv_icm42600_gyro_scan_masks;
        indio_dev->setup_ops = &inv_icm42600_buffer_ops;

        ret = devm_iio_kfifo_buffer_setup(dev, indio_dev,
                                          &inv_icm42600_buffer_ops);
        if (ret)
                return ERR_PTR(ret);

        ret = devm_iio_device_register(dev, indio_dev);
        if (ret)
                return ERR_PTR(ret);

        return indio_dev;
}

int inv_icm42600_gyro_parse_fifo(struct iio_dev *indio_dev)
{
        struct inv_icm42600_state *st = iio_device_get_drvdata(indio_dev);
        struct inv_icm42600_sensor_state *gyro_st = iio_priv(indio_dev);
        struct inv_sensors_timestamp *ts = &gyro_st->ts;
        ssize_t i, size;
        unsigned int no;
        const void *accel, *gyro, *timestamp;
        const s8 *temp;
        unsigned int odr;
        s64 ts_val;
        /* buffer is copied to userspace, zeroing it to avoid any data leak */
        struct inv_icm42600_gyro_buffer buffer = { };

        /* parse all fifo packets */
        for (i = 0, no = 0; i < st->fifo.count; i += size, ++no) {
                size = inv_icm42600_fifo_decode_packet(&st->fifo.data[i],
                                &accel, &gyro, &temp, &timestamp, &odr);
                /* quit if error or FIFO is empty */
                if (size <= 0)
                        return size;

                /* skip packet if no gyro data or data is invalid */
                if (gyro == NULL || !inv_icm42600_fifo_is_data_valid(gyro))
                        continue;

                /* update odr */
                if (odr & INV_ICM42600_SENSOR_GYRO)
                        inv_sensors_timestamp_apply_odr(ts, st->fifo.period,
                                                        st->fifo.nb.total, no);

                memcpy(&buffer.gyro, gyro, sizeof(buffer.gyro));
                /* convert 8 bits FIFO temperature in high resolution format */
                buffer.temp = temp ? (*temp * 64) : 0;
                ts_val = inv_sensors_timestamp_pop(ts);
                iio_push_to_buffers_with_timestamp(indio_dev, &buffer, ts_val);
        }

        return 0;
}