root/drivers/iio/gyro/fxas21002c_core.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for NXP FXAS21002C Gyroscope - Core
 *
 * Copyright (C) 2019 Linaro Ltd.
 */

#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>

#include <linux/iio/events.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>

#include "fxas21002c.h"

#define FXAS21002C_CHIP_ID_1    0xD6
#define FXAS21002C_CHIP_ID_2    0xD7

enum fxas21002c_mode_state {
        FXAS21002C_MODE_STANDBY,
        FXAS21002C_MODE_READY,
        FXAS21002C_MODE_ACTIVE,
};

#define FXAS21002C_STANDBY_ACTIVE_TIME_MS       62
#define FXAS21002C_READY_ACTIVE_TIME_MS         7

#define FXAS21002C_ODR_LIST_MAX         10

#define FXAS21002C_SCALE_FRACTIONAL     32
#define FXAS21002C_RANGE_LIMIT_DOUBLE   2000

#define FXAS21002C_AXIS_TO_REG(axis) (FXAS21002C_REG_OUT_X_MSB + ((axis) * 2))

static const struct reg_field fxas21002c_reg_fields[] = {
        [F_DR_STATUS]           = REG_FIELD(FXAS21002C_REG_STATUS, 0, 7),
        [F_OUT_X_MSB]           = REG_FIELD(FXAS21002C_REG_OUT_X_MSB, 0, 7),
        [F_OUT_X_LSB]           = REG_FIELD(FXAS21002C_REG_OUT_X_LSB, 0, 7),
        [F_OUT_Y_MSB]           = REG_FIELD(FXAS21002C_REG_OUT_Y_MSB, 0, 7),
        [F_OUT_Y_LSB]           = REG_FIELD(FXAS21002C_REG_OUT_Y_LSB, 0, 7),
        [F_OUT_Z_MSB]           = REG_FIELD(FXAS21002C_REG_OUT_Z_MSB, 0, 7),
        [F_OUT_Z_LSB]           = REG_FIELD(FXAS21002C_REG_OUT_Z_LSB, 0, 7),
        [F_ZYX_OW]              = REG_FIELD(FXAS21002C_REG_DR_STATUS, 7, 7),
        [F_Z_OW]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 6, 6),
        [F_Y_OW]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 5, 5),
        [F_X_OW]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 4, 4),
        [F_ZYX_DR]              = REG_FIELD(FXAS21002C_REG_DR_STATUS, 3, 3),
        [F_Z_DR]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 2, 2),
        [F_Y_DR]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 1, 1),
        [F_X_DR]                = REG_FIELD(FXAS21002C_REG_DR_STATUS, 0, 0),
        [F_OVF]                 = REG_FIELD(FXAS21002C_REG_F_STATUS, 7, 7),
        [F_WMKF]                = REG_FIELD(FXAS21002C_REG_F_STATUS, 6, 6),
        [F_CNT]                 = REG_FIELD(FXAS21002C_REG_F_STATUS, 0, 5),
        [F_MODE]                = REG_FIELD(FXAS21002C_REG_F_SETUP, 6, 7),
        [F_WMRK]                = REG_FIELD(FXAS21002C_REG_F_SETUP, 0, 5),
        [F_EVENT]               = REG_FIELD(FXAS21002C_REG_F_EVENT, 5, 5),
        [FE_TIME]               = REG_FIELD(FXAS21002C_REG_F_EVENT, 0, 4),
        [F_BOOTEND]             = REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 3, 3),
        [F_SRC_FIFO]            = REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 2, 2),
        [F_SRC_RT]              = REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 1, 1),
        [F_SRC_DRDY]            = REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 0, 0),
        [F_WHO_AM_I]            = REG_FIELD(FXAS21002C_REG_WHO_AM_I, 0, 7),
        [F_BW]                  = REG_FIELD(FXAS21002C_REG_CTRL0, 6, 7),
        [F_SPIW]                = REG_FIELD(FXAS21002C_REG_CTRL0, 5, 5),
        [F_SEL]                 = REG_FIELD(FXAS21002C_REG_CTRL0, 3, 4),
        [F_HPF_EN]              = REG_FIELD(FXAS21002C_REG_CTRL0, 2, 2),
        [F_FS]                  = REG_FIELD(FXAS21002C_REG_CTRL0, 0, 1),
        [F_ELE]                 = REG_FIELD(FXAS21002C_REG_RT_CFG, 3, 3),
        [F_ZTEFE]               = REG_FIELD(FXAS21002C_REG_RT_CFG, 2, 2),
        [F_YTEFE]               = REG_FIELD(FXAS21002C_REG_RT_CFG, 1, 1),
        [F_XTEFE]               = REG_FIELD(FXAS21002C_REG_RT_CFG, 0, 0),
        [F_EA]                  = REG_FIELD(FXAS21002C_REG_RT_SRC, 6, 6),
        [F_ZRT]                 = REG_FIELD(FXAS21002C_REG_RT_SRC, 5, 5),
        [F_ZRT_POL]             = REG_FIELD(FXAS21002C_REG_RT_SRC, 4, 4),
        [F_YRT]                 = REG_FIELD(FXAS21002C_REG_RT_SRC, 3, 3),
        [F_YRT_POL]             = REG_FIELD(FXAS21002C_REG_RT_SRC, 2, 2),
        [F_XRT]                 = REG_FIELD(FXAS21002C_REG_RT_SRC, 1, 1),
        [F_XRT_POL]             = REG_FIELD(FXAS21002C_REG_RT_SRC, 0, 0),
        [F_DBCNTM]              = REG_FIELD(FXAS21002C_REG_RT_THS, 7, 7),
        [F_THS]                 = REG_FIELD(FXAS21002C_REG_RT_SRC, 0, 6),
        [F_RT_COUNT]            = REG_FIELD(FXAS21002C_REG_RT_COUNT, 0, 7),
        [F_TEMP]                = REG_FIELD(FXAS21002C_REG_TEMP, 0, 7),
        [F_RST]                 = REG_FIELD(FXAS21002C_REG_CTRL1, 6, 6),
        [F_ST]                  = REG_FIELD(FXAS21002C_REG_CTRL1, 5, 5),
        [F_DR]                  = REG_FIELD(FXAS21002C_REG_CTRL1, 2, 4),
        [F_ACTIVE]              = REG_FIELD(FXAS21002C_REG_CTRL1, 1, 1),
        [F_READY]               = REG_FIELD(FXAS21002C_REG_CTRL1, 0, 0),
        [F_INT_CFG_FIFO]        = REG_FIELD(FXAS21002C_REG_CTRL2, 7, 7),
        [F_INT_EN_FIFO]         = REG_FIELD(FXAS21002C_REG_CTRL2, 6, 6),
        [F_INT_CFG_RT]          = REG_FIELD(FXAS21002C_REG_CTRL2, 5, 5),
        [F_INT_EN_RT]           = REG_FIELD(FXAS21002C_REG_CTRL2, 4, 4),
        [F_INT_CFG_DRDY]        = REG_FIELD(FXAS21002C_REG_CTRL2, 3, 3),
        [F_INT_EN_DRDY]         = REG_FIELD(FXAS21002C_REG_CTRL2, 2, 2),
        [F_IPOL]                = REG_FIELD(FXAS21002C_REG_CTRL2, 1, 1),
        [F_PP_OD]               = REG_FIELD(FXAS21002C_REG_CTRL2, 0, 0),
        [F_WRAPTOONE]           = REG_FIELD(FXAS21002C_REG_CTRL3, 3, 3),
        [F_EXTCTRLEN]           = REG_FIELD(FXAS21002C_REG_CTRL3, 2, 2),
        [F_FS_DOUBLE]           = REG_FIELD(FXAS21002C_REG_CTRL3, 0, 0),
};

static const int fxas21002c_odr_values[] = {
        800, 400, 200, 100, 50, 25, 12, 12
};

/*
 * These values are taken from the low-pass filter cutoff frequency calculated
 * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 0.32
 * => LPF cutoff frequency = 800 * 0.32 = 256 Hz
 */
static const int fxas21002c_lpf_values[] = {
        32, 16, 8
};

/*
 * These values are taken from the high-pass filter cutoff frequency calculated
 * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 0.018750
 * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz
 */
static const int fxas21002c_hpf_values[] = {
        18750, 9625, 4875, 2475
};

static const int fxas21002c_range_values[] = {
        4000, 2000, 1000, 500, 250
};

struct fxas21002c_data {
        u8 chip_id;
        enum fxas21002c_mode_state mode;
        enum fxas21002c_mode_state prev_mode;

        struct mutex lock;              /* serialize data access */
        struct regmap *regmap;
        struct regmap_field *regmap_fields[F_MAX_FIELDS];
        struct iio_trigger *dready_trig;
        s64 timestamp;
        int irq;

        struct regulator *vdd;
        struct regulator *vddio;

        /*
         * DMA (thus cache coherency maintenance) may require the
         * transfer buffers live in their own cache lines.
         */
        s16 buffer[8] __aligned(IIO_DMA_MINALIGN);
};

enum fxas21002c_channel_index {
        CHANNEL_SCAN_INDEX_X,
        CHANNEL_SCAN_INDEX_Y,
        CHANNEL_SCAN_INDEX_Z,
        CHANNEL_SCAN_MAX,
};

static int fxas21002c_odr_hz_from_value(struct fxas21002c_data *data, u8 value)
{
        int odr_value_max = ARRAY_SIZE(fxas21002c_odr_values) - 1;

        value = min_t(u8, value, odr_value_max);

        return fxas21002c_odr_values[value];
}

static int fxas21002c_odr_value_from_hz(struct fxas21002c_data *data,
                                        unsigned int hz)
{
        int odr_table_size = ARRAY_SIZE(fxas21002c_odr_values);
        int i;

        for (i = 0; i < odr_table_size; i++)
                if (fxas21002c_odr_values[i] == hz)
                        return i;

        return -EINVAL;
}

static int fxas21002c_lpf_bw_from_value(struct fxas21002c_data *data, u8 value)
{
        int lpf_value_max = ARRAY_SIZE(fxas21002c_lpf_values) - 1;

        value = min_t(u8, value, lpf_value_max);

        return fxas21002c_lpf_values[value];
}

static int fxas21002c_lpf_value_from_bw(struct fxas21002c_data *data,
                                        unsigned int hz)
{
        int lpf_table_size = ARRAY_SIZE(fxas21002c_lpf_values);
        int i;

        for (i = 0; i < lpf_table_size; i++)
                if (fxas21002c_lpf_values[i] == hz)
                        return i;

        return -EINVAL;
}

static int fxas21002c_hpf_sel_from_value(struct fxas21002c_data *data, u8 value)
{
        int hpf_value_max = ARRAY_SIZE(fxas21002c_hpf_values) - 1;

        value = min_t(u8, value, hpf_value_max);

        return fxas21002c_hpf_values[value];
}

static int fxas21002c_hpf_value_from_sel(struct fxas21002c_data *data,
                                         unsigned int hz)
{
        int hpf_table_size = ARRAY_SIZE(fxas21002c_hpf_values);
        int i;

        for (i = 0; i < hpf_table_size; i++)
                if (fxas21002c_hpf_values[i] == hz)
                        return i;

        return -EINVAL;
}

static int fxas21002c_range_fs_from_value(struct fxas21002c_data *data,
                                          u8 value)
{
        int range_value_max = ARRAY_SIZE(fxas21002c_range_values) - 1;
        unsigned int fs_double;
        int ret;

        /* We need to check if FS_DOUBLE is enabled to offset the value */
        ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], &fs_double);
        if (ret < 0)
                return ret;

        if (!fs_double)
                value += 1;

        value = min_t(u8, value, range_value_max);

        return fxas21002c_range_values[value];
}

static int fxas21002c_range_value_from_fs(struct fxas21002c_data *data,
                                          unsigned int range)
{
        int range_table_size = ARRAY_SIZE(fxas21002c_range_values);
        bool found = false;
        int fs_double = 0;
        int ret;
        int i;

        for (i = 0; i < range_table_size; i++)
                if (fxas21002c_range_values[i] == range) {
                        found = true;
                        break;
                }

        if (!found)
                return -EINVAL;

        if (range > FXAS21002C_RANGE_LIMIT_DOUBLE)
                fs_double = 1;

        ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], fs_double);
        if (ret < 0)
                return ret;

        return i;
}

static int fxas21002c_mode_get(struct fxas21002c_data *data)
{
        unsigned int active;
        unsigned int ready;
        int ret;

        ret = regmap_field_read(data->regmap_fields[F_ACTIVE], &active);
        if (ret < 0)
                return ret;
        if (active)
                return FXAS21002C_MODE_ACTIVE;

        ret = regmap_field_read(data->regmap_fields[F_READY], &ready);
        if (ret < 0)
                return ret;
        if (ready)
                return FXAS21002C_MODE_READY;

        return FXAS21002C_MODE_STANDBY;
}

static int fxas21002c_mode_set(struct fxas21002c_data *data,
                               enum fxas21002c_mode_state mode)
{
        int ret;

        if (mode == data->mode)
                return 0;

        if (mode == FXAS21002C_MODE_READY)
                ret = regmap_field_write(data->regmap_fields[F_READY], 1);
        else
                ret = regmap_field_write(data->regmap_fields[F_READY], 0);
        if (ret < 0)
                return ret;

        if (mode == FXAS21002C_MODE_ACTIVE)
                ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 1);
        else
                ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 0);
        if (ret < 0)
                return ret;

        /* if going to active wait the setup times */
        if (mode == FXAS21002C_MODE_ACTIVE &&
            data->mode == FXAS21002C_MODE_STANDBY)
                msleep_interruptible(FXAS21002C_STANDBY_ACTIVE_TIME_MS);

        if (data->mode == FXAS21002C_MODE_READY)
                msleep_interruptible(FXAS21002C_READY_ACTIVE_TIME_MS);

        data->prev_mode = data->mode;
        data->mode = mode;

        return ret;
}

static int fxas21002c_write(struct fxas21002c_data *data,
                            enum fxas21002c_fields field, int bits)
{
        int actual_mode;
        int ret;

        mutex_lock(&data->lock);

        actual_mode = fxas21002c_mode_get(data);
        if (actual_mode < 0) {
                ret = actual_mode;
                goto out_unlock;
        }

        ret = fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
        if (ret < 0)
                goto out_unlock;

        ret = regmap_field_write(data->regmap_fields[field], bits);
        if (ret < 0)
                goto out_unlock;

        ret = fxas21002c_mode_set(data, data->prev_mode);

out_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int  fxas21002c_pm_get(struct fxas21002c_data *data)
{
        return pm_runtime_resume_and_get(regmap_get_device(data->regmap));
}

static int  fxas21002c_pm_put(struct fxas21002c_data *data)
{
        struct device *dev = regmap_get_device(data->regmap);

        return pm_runtime_put_autosuspend(dev);
}

static int fxas21002c_temp_get(struct fxas21002c_data *data, int *val)
{
        struct device *dev = regmap_get_device(data->regmap);
        unsigned int temp;
        int ret;

        mutex_lock(&data->lock);
        ret = fxas21002c_pm_get(data);
        if (ret < 0)
                goto data_unlock;

        ret = regmap_field_read(data->regmap_fields[F_TEMP], &temp);
        if (ret < 0) {
                dev_err(dev, "failed to read temp: %d\n", ret);
                fxas21002c_pm_put(data);
                goto data_unlock;
        }

        *val = sign_extend32(temp, 7);

        ret = fxas21002c_pm_put(data);
        if (ret < 0)
                goto data_unlock;

        ret = IIO_VAL_INT;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_axis_get(struct fxas21002c_data *data,
                               int index, int *val)
{
        struct device *dev = regmap_get_device(data->regmap);
        __be16 axis_be;
        int ret;

        mutex_lock(&data->lock);
        ret = fxas21002c_pm_get(data);
        if (ret < 0)
                goto data_unlock;

        ret = regmap_bulk_read(data->regmap, FXAS21002C_AXIS_TO_REG(index),
                               &axis_be, sizeof(axis_be));
        if (ret < 0) {
                dev_err(dev, "failed to read axis: %d: %d\n", index, ret);
                fxas21002c_pm_put(data);
                goto data_unlock;
        }

        *val = sign_extend32(be16_to_cpu(axis_be), 15);

        ret = fxas21002c_pm_put(data);
        if (ret < 0)
                goto data_unlock;

        ret = IIO_VAL_INT;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_odr_get(struct fxas21002c_data *data, int *odr)
{
        unsigned int odr_bits;
        int ret;

        mutex_lock(&data->lock);
        ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);
        if (ret < 0)
                goto data_unlock;

        *odr = fxas21002c_odr_hz_from_value(data, odr_bits);

        ret = IIO_VAL_INT;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_odr_set(struct fxas21002c_data *data, int odr)
{
        int odr_bits;

        odr_bits = fxas21002c_odr_value_from_hz(data, odr);
        if (odr_bits < 0)
                return odr_bits;

        return fxas21002c_write(data, F_DR, odr_bits);
}

static int fxas21002c_lpf_get(struct fxas21002c_data *data, int *val2)
{
        unsigned int bw_bits;
        int ret;

        mutex_lock(&data->lock);
        ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);
        if (ret < 0)
                goto data_unlock;

        *val2 = fxas21002c_lpf_bw_from_value(data, bw_bits) * 10000;

        ret = IIO_VAL_INT_PLUS_MICRO;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_lpf_set(struct fxas21002c_data *data, int bw)
{
        int bw_bits;
        int odr;
        int ret;

        bw_bits = fxas21002c_lpf_value_from_bw(data, bw);
        if (bw_bits < 0)
                return bw_bits;

        /*
         * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08
         * is not allowed and for ODR = 12.5 value 0.16 is also not allowed
         */
        ret = fxas21002c_odr_get(data, &odr);
        if (ret < 0)
                return -EINVAL;

        if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))
                return -EINVAL;

        return fxas21002c_write(data, F_BW, bw_bits);
}

static int fxas21002c_hpf_get(struct fxas21002c_data *data, int *val2)
{
        unsigned int sel_bits;
        int ret;

        mutex_lock(&data->lock);
        ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);
        if (ret < 0)
                goto data_unlock;

        *val2 = fxas21002c_hpf_sel_from_value(data, sel_bits);

        ret = IIO_VAL_INT_PLUS_MICRO;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_hpf_set(struct fxas21002c_data *data, int sel)
{
        int sel_bits;

        sel_bits = fxas21002c_hpf_value_from_sel(data, sel);
        if (sel_bits < 0)
                return sel_bits;

        return fxas21002c_write(data, F_SEL, sel_bits);
}

static int fxas21002c_scale_get(struct fxas21002c_data *data, int *val)
{
        int fs_bits;
        int scale;
        int ret;

        mutex_lock(&data->lock);
        ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);
        if (ret < 0)
                goto data_unlock;

        scale = fxas21002c_range_fs_from_value(data, fs_bits);
        if (scale < 0) {
                ret = scale;
                goto data_unlock;
        }

        *val = scale;

data_unlock:
        mutex_unlock(&data->lock);

        return ret;
}

static int fxas21002c_scale_set(struct fxas21002c_data *data, int range)
{
        int fs_bits;

        fs_bits = fxas21002c_range_value_from_fs(data, range);
        if (fs_bits < 0)
                return fs_bits;

        return fxas21002c_write(data, F_FS, fs_bits);
}

static int fxas21002c_read_raw(struct iio_dev *indio_dev,
                               struct iio_chan_spec const *chan, int *val,
                               int *val2, long mask)
{
        struct fxas21002c_data *data = iio_priv(indio_dev);
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                switch (chan->type) {
                case IIO_TEMP:
                        return fxas21002c_temp_get(data, val);
                case IIO_ANGL_VEL:
                        return fxas21002c_axis_get(data, chan->scan_index, val);
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {
                case IIO_ANGL_VEL:
                        *val2 = FXAS21002C_SCALE_FRACTIONAL;
                        ret = fxas21002c_scale_get(data, val);
                        if (ret < 0)
                                return ret;

                        return IIO_VAL_FRACTIONAL;
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
                *val = 0;
                return fxas21002c_lpf_get(data, val2);
        case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
                *val = 0;
                return fxas21002c_hpf_get(data, val2);
        case IIO_CHAN_INFO_SAMP_FREQ:
                *val2 = 0;
                return fxas21002c_odr_get(data, val);
        default:
                return -EINVAL;
        }
}

static int fxas21002c_write_raw(struct iio_dev *indio_dev,
                                struct iio_chan_spec const *chan, int val,
                                int val2, long mask)
{
        struct fxas21002c_data *data = iio_priv(indio_dev);
        int range;

        switch (mask) {
        case IIO_CHAN_INFO_SAMP_FREQ:
                if (val2)
                        return -EINVAL;

                return fxas21002c_odr_set(data, val);
        case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
                if (val)
                        return -EINVAL;

                val2 = val2 / 10000;
                return fxas21002c_lpf_set(data, val2);
        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {
                case IIO_ANGL_VEL:
                        range = (((val * 1000 + val2 / 1000) *
                                  FXAS21002C_SCALE_FRACTIONAL) / 1000);
                        return fxas21002c_scale_set(data, range);
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
                return fxas21002c_hpf_set(data, val2);
        default:
                return -EINVAL;
        }
}

static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");

static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,
                      "0.32 0.16 0.08");

static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,
                      "0.018750 0.009625 0.004875 0.002475");

static IIO_CONST_ATTR(in_anglvel_scale_available,
                      "125.0 62.5 31.25 15.625 7.8125");

static struct attribute *fxas21002c_attributes[] = {
        &iio_const_attr_sampling_frequency_available.dev_attr.attr,
        &iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,
        &iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,
        &iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
        NULL,
};

static const struct attribute_group fxas21002c_attrs_group = {
        .attrs = fxas21002c_attributes,
};

#define FXAS21002C_CHANNEL(_axis) {                                     \
        .type = IIO_ANGL_VEL,                                           \
        .modified = 1,                                                  \
        .channel2 = IIO_MOD_##_axis,                                    \
        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),                   \
        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
                BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |      \
                BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY) |     \
                BIT(IIO_CHAN_INFO_SAMP_FREQ),                           \
        .scan_index = CHANNEL_SCAN_INDEX_##_axis,                       \
        .scan_type = {                                                  \
                .sign = 's',                                            \
                .realbits = 16,                                         \
                .storagebits = 16,                                      \
                .endianness = IIO_BE,                                   \
        },                                                              \
}

static const struct iio_chan_spec fxas21002c_channels[] = {
        {
                .type = IIO_TEMP,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
                .scan_index = -1,
        },
        FXAS21002C_CHANNEL(X),
        FXAS21002C_CHANNEL(Y),
        FXAS21002C_CHANNEL(Z),
};

static const struct iio_info fxas21002c_info = {
        .attrs                  = &fxas21002c_attrs_group,
        .read_raw               = &fxas21002c_read_raw,
        .write_raw              = &fxas21002c_write_raw,
};

static irqreturn_t fxas21002c_trigger_handler(int irq, void *p)
{
        struct iio_poll_func *pf = p;
        struct iio_dev *indio_dev = pf->indio_dev;
        struct fxas21002c_data *data = iio_priv(indio_dev);
        int ret;

        mutex_lock(&data->lock);
        ret = fxas21002c_pm_get(data);
        if (ret < 0)
                goto out_unlock;

        ret = regmap_bulk_read(data->regmap, FXAS21002C_REG_OUT_X_MSB,
                               data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
        if (ret < 0)
                goto out_pm_put;

        iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
                                           data->timestamp);

out_pm_put:
        fxas21002c_pm_put(data);

out_unlock:
        mutex_unlock(&data->lock);

        iio_trigger_notify_done(indio_dev->trig);

        return IRQ_HANDLED;
}

static int fxas21002c_chip_init(struct fxas21002c_data *data)
{
        struct device *dev = regmap_get_device(data->regmap);
        unsigned int chip_id;
        int ret;

        ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);
        if (ret < 0)
                return ret;

        if (chip_id != FXAS21002C_CHIP_ID_1 &&
            chip_id != FXAS21002C_CHIP_ID_2) {
                dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);
                return -EINVAL;
        }

        data->chip_id = chip_id;

        ret = fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
        if (ret < 0)
                return ret;

        /* Set ODR to 200HZ as default */
        ret = fxas21002c_odr_set(data, 200);
        if (ret < 0)
                dev_err(dev, "failed to set ODR: %d\n", ret);

        return ret;
}

static int fxas21002c_data_rdy_trigger_set_state(struct iio_trigger *trig,
                                                 bool state)
{
        struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
        struct fxas21002c_data *data = iio_priv(indio_dev);

        return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);
}

static const struct iio_trigger_ops fxas21002c_trigger_ops = {
        .set_trigger_state = &fxas21002c_data_rdy_trigger_set_state,
};

static irqreturn_t fxas21002c_data_rdy_handler(int irq, void *private)
{
        struct iio_dev *indio_dev = private;
        struct fxas21002c_data *data = iio_priv(indio_dev);

        data->timestamp = iio_get_time_ns(indio_dev);

        return IRQ_WAKE_THREAD;
}

static irqreturn_t fxas21002c_data_rdy_thread(int irq, void *private)
{
        struct iio_dev *indio_dev = private;
        struct fxas21002c_data *data = iio_priv(indio_dev);
        unsigned int data_ready;
        int ret;

        ret = regmap_field_read(data->regmap_fields[F_SRC_DRDY], &data_ready);
        if (ret < 0)
                return IRQ_NONE;

        if (!data_ready)
                return IRQ_NONE;

        iio_trigger_poll_nested(data->dready_trig);

        return IRQ_HANDLED;
}

static int fxas21002c_trigger_probe(struct fxas21002c_data *data)
{
        struct device *dev = regmap_get_device(data->regmap);
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        unsigned long irq_trig;
        bool irq_open_drain;
        int irq1;
        int ret;

        if (!data->irq)
                return 0;

        irq1 = fwnode_irq_get_byname(dev_fwnode(dev), "INT1");
        if (irq1 == data->irq) {
                dev_info(dev, "using interrupt line INT1\n");
                ret = regmap_field_write(data->regmap_fields[F_INT_CFG_DRDY],
                                         1);
                if (ret < 0)
                        return ret;
        }

        dev_info(dev, "using interrupt line INT2\n");

        irq_open_drain = device_property_read_bool(dev, "drive-open-drain");

        data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
                                                   indio_dev->name,
                                                   iio_device_id(indio_dev));
        if (!data->dready_trig)
                return -ENOMEM;

        irq_trig = irq_get_trigger_type(data->irq);
        if (irq_trig == IRQF_TRIGGER_RISING) {
                ret = regmap_field_write(data->regmap_fields[F_IPOL], 1);
                if (ret < 0)
                        return ret;
        }

        if (irq_open_drain)
                irq_trig |= IRQF_SHARED;

        ret = devm_request_threaded_irq(dev, data->irq,
                                        fxas21002c_data_rdy_handler,
                                        fxas21002c_data_rdy_thread,
                                        irq_trig, "fxas21002c_data_ready",
                                        indio_dev);
        if (ret < 0)
                return ret;

        data->dready_trig->ops = &fxas21002c_trigger_ops;
        iio_trigger_set_drvdata(data->dready_trig, indio_dev);

        return devm_iio_trigger_register(dev, data->dready_trig);
}

static int fxas21002c_power_enable(struct fxas21002c_data *data)
{
        int ret;

        ret = regulator_enable(data->vdd);
        if (ret < 0)
                return ret;

        ret = regulator_enable(data->vddio);
        if (ret < 0) {
                regulator_disable(data->vdd);
                return ret;
        }

        return 0;
}

static void fxas21002c_power_disable(struct fxas21002c_data *data)
{
        regulator_disable(data->vdd);
        regulator_disable(data->vddio);
}

static void fxas21002c_power_disable_action(void *_data)
{
        struct fxas21002c_data *data = _data;

        fxas21002c_power_disable(data);
}

static int fxas21002c_regulators_get(struct fxas21002c_data *data)
{
        struct device *dev = regmap_get_device(data->regmap);

        data->vdd = devm_regulator_get(dev->parent, "vdd");
        if (IS_ERR(data->vdd))
                return PTR_ERR(data->vdd);

        data->vddio = devm_regulator_get(dev->parent, "vddio");

        return PTR_ERR_OR_ZERO(data->vddio);
}

int fxas21002c_core_probe(struct device *dev, struct regmap *regmap, int irq,
                          const char *name)
{
        struct fxas21002c_data *data;
        struct iio_dev *indio_dev;
        struct regmap_field *f;
        int i;
        int ret;

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

        data = iio_priv(indio_dev);
        dev_set_drvdata(dev, indio_dev);
        data->irq = irq;
        data->regmap = regmap;

        for (i = 0; i < F_MAX_FIELDS; i++) {
                f = devm_regmap_field_alloc(dev, data->regmap,
                                            fxas21002c_reg_fields[i]);
                if (IS_ERR(f))
                        return PTR_ERR(f);

                data->regmap_fields[i] = f;
        }

        mutex_init(&data->lock);

        ret = fxas21002c_regulators_get(data);
        if (ret < 0)
                return ret;

        ret = fxas21002c_power_enable(data);
        if (ret < 0)
                return ret;

        ret = devm_add_action_or_reset(dev, fxas21002c_power_disable_action,
                                       data);
        if (ret < 0)
                return ret;

        ret = fxas21002c_chip_init(data);
        if (ret < 0)
                return ret;

        indio_dev->channels = fxas21002c_channels;
        indio_dev->num_channels = ARRAY_SIZE(fxas21002c_channels);
        indio_dev->name = name;
        indio_dev->modes = INDIO_DIRECT_MODE;
        indio_dev->info = &fxas21002c_info;

        ret = fxas21002c_trigger_probe(data);
        if (ret < 0)
                return ret;

        ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
                                              fxas21002c_trigger_handler, NULL);
        if (ret < 0)
                return ret;

        ret = pm_runtime_set_active(dev);
        if (ret)
                return ret;

        pm_runtime_enable(dev);
        pm_runtime_set_autosuspend_delay(dev, 2000);
        pm_runtime_use_autosuspend(dev);

        ret = iio_device_register(indio_dev);
        if (ret < 0)
                goto pm_disable;

        return 0;

pm_disable:
        pm_runtime_disable(dev);
        pm_runtime_set_suspended(dev);

        return ret;
}
EXPORT_SYMBOL_NS_GPL(fxas21002c_core_probe, "IIO_FXAS21002C");

void fxas21002c_core_remove(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);

        iio_device_unregister(indio_dev);

        pm_runtime_disable(dev);
        pm_runtime_set_suspended(dev);
}
EXPORT_SYMBOL_NS_GPL(fxas21002c_core_remove, "IIO_FXAS21002C");

static int fxas21002c_suspend(struct device *dev)
{
        struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));

        fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
        fxas21002c_power_disable(data);

        return 0;
}

static int fxas21002c_resume(struct device *dev)
{
        struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
        int ret;

        ret = fxas21002c_power_enable(data);
        if (ret < 0)
                return ret;

        return fxas21002c_mode_set(data, data->prev_mode);
}

static int fxas21002c_runtime_suspend(struct device *dev)
{
        struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));

        return fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
}

static int fxas21002c_runtime_resume(struct device *dev)
{
        struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));

        return fxas21002c_mode_set(data, FXAS21002C_MODE_ACTIVE);
}

EXPORT_NS_GPL_DEV_PM_OPS(fxas21002c_pm_ops, IIO_FXAS21002C) = {
        SYSTEM_SLEEP_PM_OPS(fxas21002c_suspend, fxas21002c_resume)
        RUNTIME_PM_OPS(fxas21002c_runtime_suspend, fxas21002c_runtime_resume,
                       NULL)
};

MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("FXAS21002C Gyro driver");