root/drivers/iio/magnetometer/bmc150_magn.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Bosch BMC150 three-axis magnetic field sensor driver
 *
 * Copyright (c) 2015, Intel Corporation.
 *
 * This code is based on bmm050_api.c authored by contact@bosch.sensortec.com:
 *
 * (C) Copyright 2011~2014 Bosch Sensortec GmbH All Rights Reserved
 */

#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/events.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>

#include "bmc150_magn.h"

#define BMC150_MAGN_REG_CHIP_ID                 0x40
#define BMC150_MAGN_CHIP_ID_VAL                 0x32

#define BMC150_MAGN_REG_X_L                     0x42
#define BMC150_MAGN_REG_X_M                     0x43
#define BMC150_MAGN_REG_Y_L                     0x44
#define BMC150_MAGN_REG_Y_M                     0x45
#define BMC150_MAGN_SHIFT_XY_L                  3
#define BMC150_MAGN_REG_Z_L                     0x46
#define BMC150_MAGN_REG_Z_M                     0x47
#define BMC150_MAGN_SHIFT_Z_L                   1
#define BMC150_MAGN_REG_RHALL_L                 0x48
#define BMC150_MAGN_REG_RHALL_M                 0x49
#define BMC150_MAGN_SHIFT_RHALL_L               2

#define BMC150_MAGN_REG_INT_STATUS              0x4A

#define BMC150_MAGN_REG_POWER                   0x4B
#define BMC150_MAGN_MASK_POWER_CTL              BIT(0)

#define BMC150_MAGN_REG_OPMODE_ODR              0x4C
#define BMC150_MAGN_MASK_OPMODE                 GENMASK(2, 1)
#define BMC150_MAGN_SHIFT_OPMODE                1
#define BMC150_MAGN_MODE_NORMAL                 0x00
#define BMC150_MAGN_MODE_FORCED                 0x01
#define BMC150_MAGN_MODE_SLEEP                  0x03
#define BMC150_MAGN_MASK_ODR                    GENMASK(5, 3)
#define BMC150_MAGN_SHIFT_ODR                   3

#define BMC150_MAGN_REG_INT                     0x4D

#define BMC150_MAGN_REG_INT_DRDY                0x4E
#define BMC150_MAGN_MASK_DRDY_EN                BIT(7)
#define BMC150_MAGN_SHIFT_DRDY_EN               7
#define BMC150_MAGN_MASK_DRDY_INT3              BIT(6)
#define BMC150_MAGN_MASK_DRDY_Z_EN              BIT(5)
#define BMC150_MAGN_MASK_DRDY_Y_EN              BIT(4)
#define BMC150_MAGN_MASK_DRDY_X_EN              BIT(3)
#define BMC150_MAGN_MASK_DRDY_DR_POLARITY       BIT(2)
#define BMC150_MAGN_MASK_DRDY_LATCHING          BIT(1)
#define BMC150_MAGN_MASK_DRDY_INT3_POLARITY     BIT(0)

#define BMC150_MAGN_REG_LOW_THRESH              0x4F
#define BMC150_MAGN_REG_HIGH_THRESH             0x50
#define BMC150_MAGN_REG_REP_XY                  0x51
#define BMC150_MAGN_REG_REP_Z                   0x52
#define BMC150_MAGN_REG_REP_DATAMASK            GENMASK(7, 0)

#define BMC150_MAGN_REG_TRIM_START              0x5D
#define BMC150_MAGN_REG_TRIM_END                0x71

#define BMC150_MAGN_XY_OVERFLOW_VAL             -4096
#define BMC150_MAGN_Z_OVERFLOW_VAL              -16384

/* Time from SUSPEND to SLEEP */
#define BMC150_MAGN_START_UP_TIME_MS            3

#define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS       2000

#define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
#define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
#define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
#define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)

enum bmc150_magn_axis {
        AXIS_X,
        AXIS_Y,
        AXIS_Z,
        RHALL,
        AXIS_XYZ_MAX = RHALL,
        AXIS_XYZR_MAX,
};

enum bmc150_magn_power_modes {
        BMC150_MAGN_POWER_MODE_SUSPEND,
        BMC150_MAGN_POWER_MODE_SLEEP,
        BMC150_MAGN_POWER_MODE_NORMAL,
};

struct bmc150_magn_trim_regs {
        s8 x1;
        s8 y1;
        __le16 reserved1;
        u8 reserved2;
        __le16 z4;
        s8 x2;
        s8 y2;
        __le16 reserved3;
        __le16 z2;
        __le16 z1;
        __le16 xyz1;
        __le16 z3;
        s8 xy2;
        u8 xy1;
} __packed;

struct bmc150_magn_data {
        struct device *dev;
        /*
         * 1. Protect this structure.
         * 2. Serialize sequences that power on/off the device and access HW.
         */
        struct mutex mutex;
        struct regmap *regmap;
        struct regulator_bulk_data regulators[2];
        struct iio_mount_matrix orientation;
        /* Ensure timestamp is naturally aligned */
        struct {
                s32 chans[3];
                aligned_s64 timestamp;
        } scan;
        struct iio_trigger *dready_trig;
        bool dready_trigger_on;
        int max_odr;
        int irq;
};

static const struct {
        int freq;
        u8 reg_val;
} bmc150_magn_samp_freq_table[] = { {2, 0x01},
                                    {6, 0x02},
                                    {8, 0x03},
                                    {10, 0x00},
                                    {15, 0x04},
                                    {20, 0x05},
                                    {25, 0x06},
                                    {30, 0x07} };

enum bmc150_magn_presets {
        LOW_POWER_PRESET,
        REGULAR_PRESET,
        ENHANCED_REGULAR_PRESET,
        HIGH_ACCURACY_PRESET
};

static const struct bmc150_magn_preset {
        u8 rep_xy;
        u8 rep_z;
        u8 odr;
} bmc150_magn_presets_table[] = {
        [LOW_POWER_PRESET] = {3, 3, 10},
        [REGULAR_PRESET] =  {9, 15, 10},
        [ENHANCED_REGULAR_PRESET] =  {15, 27, 10},
        [HIGH_ACCURACY_PRESET] =  {47, 83, 20},
};

#define BMC150_MAGN_DEFAULT_PRESET REGULAR_PRESET

static bool bmc150_magn_is_writeable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case BMC150_MAGN_REG_POWER:
        case BMC150_MAGN_REG_OPMODE_ODR:
        case BMC150_MAGN_REG_INT:
        case BMC150_MAGN_REG_INT_DRDY:
        case BMC150_MAGN_REG_LOW_THRESH:
        case BMC150_MAGN_REG_HIGH_THRESH:
        case BMC150_MAGN_REG_REP_XY:
        case BMC150_MAGN_REG_REP_Z:
                return true;
        default:
                return false;
        }
}

static bool bmc150_magn_is_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case BMC150_MAGN_REG_X_L:
        case BMC150_MAGN_REG_X_M:
        case BMC150_MAGN_REG_Y_L:
        case BMC150_MAGN_REG_Y_M:
        case BMC150_MAGN_REG_Z_L:
        case BMC150_MAGN_REG_Z_M:
        case BMC150_MAGN_REG_RHALL_L:
        case BMC150_MAGN_REG_RHALL_M:
        case BMC150_MAGN_REG_INT_STATUS:
                return true;
        default:
                return false;
        }
}

const struct regmap_config bmc150_magn_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,

        .max_register = BMC150_MAGN_REG_TRIM_END,
        .cache_type = REGCACHE_RBTREE,

        .writeable_reg = bmc150_magn_is_writeable_reg,
        .volatile_reg = bmc150_magn_is_volatile_reg,
};
EXPORT_SYMBOL_NS(bmc150_magn_regmap_config, "IIO_BMC150_MAGN");

static int bmc150_magn_set_power_mode(struct bmc150_magn_data *data,
                                      enum bmc150_magn_power_modes mode,
                                      bool state)
{
        int ret;

        switch (mode) {
        case BMC150_MAGN_POWER_MODE_SUSPEND:
                ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_POWER,
                                         BMC150_MAGN_MASK_POWER_CTL, !state);
                if (ret < 0)
                        return ret;
                usleep_range(BMC150_MAGN_START_UP_TIME_MS * 1000, 20000);
                return 0;
        case BMC150_MAGN_POWER_MODE_SLEEP:
                return regmap_update_bits(data->regmap,
                                          BMC150_MAGN_REG_OPMODE_ODR,
                                          BMC150_MAGN_MASK_OPMODE,
                                          BMC150_MAGN_MODE_SLEEP <<
                                          BMC150_MAGN_SHIFT_OPMODE);
        case BMC150_MAGN_POWER_MODE_NORMAL:
                return regmap_update_bits(data->regmap,
                                          BMC150_MAGN_REG_OPMODE_ODR,
                                          BMC150_MAGN_MASK_OPMODE,
                                          BMC150_MAGN_MODE_NORMAL <<
                                          BMC150_MAGN_SHIFT_OPMODE);
        }

        return -EINVAL;
}

static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
{
        int ret = 0;

        if (on)
                ret = pm_runtime_resume_and_get(data->dev);
        else
                pm_runtime_put_autosuspend(data->dev);
        if (ret < 0) {
                dev_err(data->dev,
                        "failed to change power state to %d\n", on);
                return ret;
        }

        return 0;
}

static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
{
        int ret, reg_val;
        u8 i, odr_val;

        ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
        if (ret < 0)
                return ret;
        odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;

        for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
                if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
                        *val = bmc150_magn_samp_freq_table[i].freq;
                        return 0;
                }

        return -EINVAL;
}

static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
{
        int ret;
        u8 i;

        for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
                if (bmc150_magn_samp_freq_table[i].freq == val) {
                        ret = regmap_update_bits(data->regmap,
                                                 BMC150_MAGN_REG_OPMODE_ODR,
                                                 BMC150_MAGN_MASK_ODR,
                                                 bmc150_magn_samp_freq_table[i].
                                                 reg_val <<
                                                 BMC150_MAGN_SHIFT_ODR);
                        if (ret < 0)
                                return ret;
                        return 0;
                }
        }

        return -EINVAL;
}

static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
                                   int rep_z, int odr)
{
        int ret, reg_val, max_odr;

        if (rep_xy <= 0) {
                ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
                                  &reg_val);
                if (ret < 0)
                        return ret;
                rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
        }
        if (rep_z <= 0) {
                ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
                                  &reg_val);
                if (ret < 0)
                        return ret;
                rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
        }
        if (odr <= 0) {
                ret = bmc150_magn_get_odr(data, &odr);
                if (ret < 0)
                        return ret;
        }
        /* the maximum selectable read-out frequency from datasheet */
        max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
        if (odr > max_odr) {
                dev_err(data->dev,
                        "Can't set oversampling with sampling freq %d\n",
                        odr);
                return -EINVAL;
        }
        data->max_odr = max_odr;

        return 0;
}

static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
                                    u16 rhall)
{
        s16 val;
        u16 xyz1 = le16_to_cpu(tregs->xyz1);

        if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
                return S32_MIN;

        if (!rhall)
                rhall = xyz1;

        val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
        val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
              ((s32)val)) >> 7)) + (((s32)val) *
              ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
              ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
              (((s16)tregs->x1) << 3);

        return (s32)val;
}

static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
                                    u16 rhall)
{
        s16 val;
        u16 xyz1 = le16_to_cpu(tregs->xyz1);

        if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
                return S32_MIN;

        if (!rhall)
                rhall = xyz1;

        val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
        val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
              ((s32)val)) >> 7)) + (((s32)val) *
              ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
              ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
              (((s16)tregs->y1) << 3);

        return (s32)val;
}

static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
                                    u16 rhall)
{
        s32 val;
        u16 xyz1 = le16_to_cpu(tregs->xyz1);
        u16 z1 = le16_to_cpu(tregs->z1);
        s16 z2 = le16_to_cpu(tregs->z2);
        s16 z3 = le16_to_cpu(tregs->z3);
        s16 z4 = le16_to_cpu(tregs->z4);

        if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
                return S32_MIN;

        val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
              ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
              ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));

        return val;
}

static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
{
        int ret;
        __le16 values[AXIS_XYZR_MAX];
        s16 raw_x, raw_y, raw_z;
        u16 rhall;
        struct bmc150_magn_trim_regs tregs;

        ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
                               values, sizeof(values));
        if (ret < 0)
                return ret;

        raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
        raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
        raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
        rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;

        ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
                               &tregs, sizeof(tregs));
        if (ret < 0)
                return ret;

        buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
        buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
        buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);

        return 0;
}

static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
                                struct iio_chan_spec const *chan,
                                int *val, int *val2, long mask)
{
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret, tmp;
        s32 values[AXIS_XYZ_MAX];

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (iio_buffer_enabled(indio_dev))
                        return -EBUSY;
                mutex_lock(&data->mutex);

                ret = bmc150_magn_set_power_state(data, true);
                if (ret < 0) {
                        mutex_unlock(&data->mutex);
                        return ret;
                }

                ret = bmc150_magn_read_xyz(data, values);
                if (ret < 0) {
                        bmc150_magn_set_power_state(data, false);
                        mutex_unlock(&data->mutex);
                        return ret;
                }
                *val = values[chan->scan_index];

                ret = bmc150_magn_set_power_state(data, false);
                if (ret < 0) {
                        mutex_unlock(&data->mutex);
                        return ret;
                }

                mutex_unlock(&data->mutex);
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                /*
                 * The API/driver performs an off-chip temperature
                 * compensation and outputs x/y/z magnetic field data in
                 * 16 LSB/uT to the upper application layer.
                 */
                *val = 0;
                *val2 = 625;
                return IIO_VAL_INT_PLUS_MICRO;
        case IIO_CHAN_INFO_SAMP_FREQ:
                ret = bmc150_magn_get_odr(data, val);
                if (ret < 0)
                        return ret;
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
                switch (chan->channel2) {
                case IIO_MOD_X:
                case IIO_MOD_Y:
                        ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
                                          &tmp);
                        if (ret < 0)
                                return ret;
                        *val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
                        return IIO_VAL_INT;
                case IIO_MOD_Z:
                        ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
                                          &tmp);
                        if (ret < 0)
                                return ret;
                        *val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
                        return IIO_VAL_INT;
                default:
                        return -EINVAL;
                }
        default:
                return -EINVAL;
        }
}

static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
                                 struct iio_chan_spec const *chan,
                                 int val, int val2, long mask)
{
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_SAMP_FREQ:
                if (val > data->max_odr)
                        return -EINVAL;
                mutex_lock(&data->mutex);
                ret = bmc150_magn_set_odr(data, val);
                mutex_unlock(&data->mutex);
                return ret;
        case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
                switch (chan->channel2) {
                case IIO_MOD_X:
                case IIO_MOD_Y:
                        if (val < 1 || val > 511)
                                return -EINVAL;
                        mutex_lock(&data->mutex);
                        ret = bmc150_magn_set_max_odr(data, val, 0, 0);
                        if (ret < 0) {
                                mutex_unlock(&data->mutex);
                                return ret;
                        }
                        ret = regmap_update_bits(data->regmap,
                                                 BMC150_MAGN_REG_REP_XY,
                                                 BMC150_MAGN_REG_REP_DATAMASK,
                                                 BMC150_MAGN_REPXY_TO_REGVAL
                                                 (val));
                        mutex_unlock(&data->mutex);
                        return ret;
                case IIO_MOD_Z:
                        if (val < 1 || val > 256)
                                return -EINVAL;
                        mutex_lock(&data->mutex);
                        ret = bmc150_magn_set_max_odr(data, 0, val, 0);
                        if (ret < 0) {
                                mutex_unlock(&data->mutex);
                                return ret;
                        }
                        ret = regmap_update_bits(data->regmap,
                                                 BMC150_MAGN_REG_REP_Z,
                                                 BMC150_MAGN_REG_REP_DATAMASK,
                                                 BMC150_MAGN_REPZ_TO_REGVAL
                                                 (val));
                        mutex_unlock(&data->mutex);
                        return ret;
                default:
                        return -EINVAL;
                }
        default:
                return -EINVAL;
        }
}

static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
                                                struct device_attribute *attr,
                                                char *buf)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        size_t len = 0;
        u8 i;

        for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
                if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
                        break;
                len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
                                 bmc150_magn_samp_freq_table[i].freq);
        }
        /* replace last space with a newline */
        buf[len - 1] = '\n';

        return len;
}

static const struct iio_mount_matrix *
bmc150_magn_get_mount_matrix(const struct iio_dev *indio_dev,
                              const struct iio_chan_spec *chan)
{
        struct bmc150_magn_data *data = iio_priv(indio_dev);

        return &data->orientation;
}

static const struct iio_chan_spec_ext_info bmc150_magn_ext_info[] = {
        IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bmc150_magn_get_mount_matrix),
        { }
};

static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);

static struct attribute *bmc150_magn_attributes[] = {
        &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
        NULL,
};

static const struct attribute_group bmc150_magn_attrs_group = {
        .attrs = bmc150_magn_attributes,
};

#define BMC150_MAGN_CHANNEL(_axis) {                                    \
        .type = IIO_MAGN,                                               \
        .modified = 1,                                                  \
        .channel2 = IIO_MOD_##_axis,                                    \
        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
                              BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),    \
        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |      \
                                    BIT(IIO_CHAN_INFO_SCALE),           \
        .scan_index = AXIS_##_axis,                                     \
        .scan_type = {                                                  \
                .sign = 's',                                            \
                .realbits = 32,                                         \
                .storagebits = 32,                                      \
                .endianness = IIO_LE                                    \
        },                                                              \
        .ext_info = bmc150_magn_ext_info,                               \
}

static const struct iio_chan_spec bmc150_magn_channels[] = {
        BMC150_MAGN_CHANNEL(X),
        BMC150_MAGN_CHANNEL(Y),
        BMC150_MAGN_CHANNEL(Z),
        IIO_CHAN_SOFT_TIMESTAMP(3),
};

static const struct iio_info bmc150_magn_info = {
        .attrs = &bmc150_magn_attrs_group,
        .read_raw = bmc150_magn_read_raw,
        .write_raw = bmc150_magn_write_raw,
};

static const unsigned long bmc150_magn_scan_masks[] = {
                                        BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
                                        0};

static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
{
        struct iio_poll_func *pf = p;
        struct iio_dev *indio_dev = pf->indio_dev;
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        mutex_lock(&data->mutex);
        ret = bmc150_magn_read_xyz(data, data->scan.chans);
        if (ret < 0)
                goto err;

        iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
                                    pf->timestamp);

err:
        mutex_unlock(&data->mutex);
        iio_trigger_notify_done(indio_dev->trig);

        return IRQ_HANDLED;
}

static int bmc150_magn_init(struct bmc150_magn_data *data)
{
        int ret, chip_id;
        struct bmc150_magn_preset preset;

        ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
                                    data->regulators);
        if (ret < 0) {
                dev_err(data->dev, "Failed to enable regulators: %d\n", ret);
                return ret;
        }
        /*
         * 3ms power-on time according to datasheet, let's better
         * be safe than sorry and set this delay to 5ms.
         */
        msleep(5);

        ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
                                         false);
        if (ret < 0) {
                dev_err(data->dev,
                        "Failed to bring up device from suspend mode\n");
                goto err_regulator_disable;
        }

        ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
        if (ret < 0) {
                dev_err(data->dev, "Failed reading chip id\n");
                goto err_poweroff;
        }
        if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
                dev_err(data->dev, "Invalid chip id 0x%x\n", chip_id);
                ret = -ENODEV;
                goto err_poweroff;
        }
        dev_dbg(data->dev, "Chip id %x\n", chip_id);

        preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
        ret = bmc150_magn_set_odr(data, preset.odr);
        if (ret < 0) {
                dev_err(data->dev, "Failed to set ODR to %d\n",
                        preset.odr);
                goto err_poweroff;
        }

        ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
                           BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
        if (ret < 0) {
                dev_err(data->dev, "Failed to set REP XY to %d\n",
                        preset.rep_xy);
                goto err_poweroff;
        }

        ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
                           BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
        if (ret < 0) {
                dev_err(data->dev, "Failed to set REP Z to %d\n",
                        preset.rep_z);
                goto err_poweroff;
        }

        ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
                                      preset.odr);
        if (ret < 0)
                goto err_poweroff;

        ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
                                         true);
        if (ret < 0) {
                dev_err(data->dev, "Failed to power on device\n");
                goto err_poweroff;
        }

        return 0;

err_poweroff:
        bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
err_regulator_disable:
        regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
        return ret;
}

static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
{
        int tmp;

        /*
         * Data Ready (DRDY) is always cleared after
         * readout of data registers ends.
         */
        return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
}

static void bmc150_magn_trig_reen(struct iio_trigger *trig)
{
        struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        if (!data->dready_trigger_on)
                return;

        mutex_lock(&data->mutex);
        ret = bmc150_magn_reset_intr(data);
        mutex_unlock(&data->mutex);
        if (ret)
                dev_err(data->dev, "Failed to reset interrupt\n");
}

static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
                                                  bool state)
{
        struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret = 0;

        mutex_lock(&data->mutex);
        if (state == data->dready_trigger_on)
                goto err_unlock;

        ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
                                 BMC150_MAGN_MASK_DRDY_EN,
                                 state << BMC150_MAGN_SHIFT_DRDY_EN);
        if (ret < 0)
                goto err_unlock;

        data->dready_trigger_on = state;

        if (state) {
                ret = bmc150_magn_reset_intr(data);
                if (ret < 0)
                        goto err_unlock;
        }
        mutex_unlock(&data->mutex);

        return 0;

err_unlock:
        mutex_unlock(&data->mutex);
        return ret;
}

static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
        .set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
        .reenable = bmc150_magn_trig_reen,
};

static int bmc150_magn_buffer_preenable(struct iio_dev *indio_dev)
{
        struct bmc150_magn_data *data = iio_priv(indio_dev);

        return bmc150_magn_set_power_state(data, true);
}

static int bmc150_magn_buffer_postdisable(struct iio_dev *indio_dev)
{
        struct bmc150_magn_data *data = iio_priv(indio_dev);

        return bmc150_magn_set_power_state(data, false);
}

static const struct iio_buffer_setup_ops bmc150_magn_buffer_setup_ops = {
        .preenable = bmc150_magn_buffer_preenable,
        .postdisable = bmc150_magn_buffer_postdisable,
};

int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
                      int irq, const char *name)
{
        struct bmc150_magn_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);
        dev_set_drvdata(dev, indio_dev);
        data->regmap = regmap;
        data->irq = irq;
        data->dev = dev;

        data->regulators[0].supply = "vdd";
        data->regulators[1].supply = "vddio";
        ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
                                      data->regulators);
        if (ret)
                return dev_err_probe(dev, ret, "failed to get regulators\n");

        ret = iio_read_mount_matrix(dev, &data->orientation);
        if (ret)
                return ret;

        mutex_init(&data->mutex);

        ret = bmc150_magn_init(data);
        if (ret < 0)
                return ret;

        indio_dev->channels = bmc150_magn_channels;
        indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
        indio_dev->available_scan_masks = bmc150_magn_scan_masks;
        indio_dev->name = name;
        indio_dev->modes = INDIO_DIRECT_MODE;
        indio_dev->info = &bmc150_magn_info;

        if (irq > 0) {
                data->dready_trig = devm_iio_trigger_alloc(dev,
                                                           "%s-dev%d",
                                                           indio_dev->name,
                                                           iio_device_id(indio_dev));
                if (!data->dready_trig) {
                        ret = -ENOMEM;
                        dev_err(dev, "iio trigger alloc failed\n");
                        goto err_poweroff;
                }

                data->dready_trig->ops = &bmc150_magn_trigger_ops;
                iio_trigger_set_drvdata(data->dready_trig, indio_dev);
                ret = iio_trigger_register(data->dready_trig);
                if (ret) {
                        dev_err(dev, "iio trigger register failed\n");
                        goto err_poweroff;
                }

                ret = request_irq(irq, iio_trigger_generic_data_rdy_poll,
                                  IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
                                  "bmc150_magn_event", data->dready_trig);
                if (ret < 0) {
                        dev_err(dev, "request irq %d failed\n", irq);
                        goto err_trigger_unregister;
                }
        }

        ret = iio_triggered_buffer_setup(indio_dev,
                                         iio_pollfunc_store_time,
                                         bmc150_magn_trigger_handler,
                                         &bmc150_magn_buffer_setup_ops);
        if (ret < 0) {
                dev_err(dev, "iio triggered buffer setup failed\n");
                goto err_free_irq;
        }

        ret = pm_runtime_set_active(dev);
        if (ret)
                goto err_buffer_cleanup;

        pm_runtime_enable(dev);
        pm_runtime_set_autosuspend_delay(dev,
                                         BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
        pm_runtime_use_autosuspend(dev);

        ret = iio_device_register(indio_dev);
        if (ret < 0) {
                dev_err(dev, "unable to register iio device\n");
                goto err_pm_cleanup;
        }

        dev_dbg(dev, "Registered device %s\n", name);
        return 0;

err_pm_cleanup:
        pm_runtime_dont_use_autosuspend(dev);
        pm_runtime_disable(dev);
err_buffer_cleanup:
        iio_triggered_buffer_cleanup(indio_dev);
err_free_irq:
        if (irq > 0)
                free_irq(irq, data->dready_trig);
err_trigger_unregister:
        if (data->dready_trig)
                iio_trigger_unregister(data->dready_trig);
err_poweroff:
        bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
        return ret;
}
EXPORT_SYMBOL_NS(bmc150_magn_probe, "IIO_BMC150_MAGN");

void bmc150_magn_remove(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);

        iio_device_unregister(indio_dev);

        pm_runtime_disable(dev);
        pm_runtime_set_suspended(dev);

        iio_triggered_buffer_cleanup(indio_dev);

        if (data->irq > 0)
                free_irq(data->irq, data->dready_trig);

        if (data->dready_trig)
                iio_trigger_unregister(data->dready_trig);

        mutex_lock(&data->mutex);
        bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
        mutex_unlock(&data->mutex);

        regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
}
EXPORT_SYMBOL_NS(bmc150_magn_remove, "IIO_BMC150_MAGN");

#ifdef CONFIG_PM
static int bmc150_magn_runtime_suspend(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        mutex_lock(&data->mutex);
        ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
                                         true);
        mutex_unlock(&data->mutex);
        if (ret < 0) {
                dev_err(dev, "powering off device failed\n");
                return ret;
        }
        return 0;
}

/*
 * Should be called with data->mutex held.
 */
static int bmc150_magn_runtime_resume(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);

        return bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
                                          true);
}
#endif

#ifdef CONFIG_PM_SLEEP
static int bmc150_magn_suspend(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        mutex_lock(&data->mutex);
        ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
                                         true);
        mutex_unlock(&data->mutex);

        return ret;
}

static int bmc150_magn_resume(struct device *dev)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct bmc150_magn_data *data = iio_priv(indio_dev);
        int ret;

        mutex_lock(&data->mutex);
        ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
                                         true);
        mutex_unlock(&data->mutex);

        return ret;
}
#endif

const struct dev_pm_ops bmc150_magn_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(bmc150_magn_suspend, bmc150_magn_resume)
        SET_RUNTIME_PM_OPS(bmc150_magn_runtime_suspend,
                           bmc150_magn_runtime_resume, NULL)
};
EXPORT_SYMBOL_NS(bmc150_magn_pm_ops, "IIO_BMC150_MAGN");

MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("BMC150 magnetometer core driver");