// SPDX-License-Identifier: GPL-2.0-only
/*
 * mpl3115.c - Support for Freescale MPL3115A2 pressure/temperature sensor
 *
 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
 *
 * (7-bit I2C slave address 0x60)
 *
 * TODO: FIFO buffer, altimeter mode, oversampling, continuous mode,
 * user offset correction, raw mode
 */

#include <linux/bitfield.h>
#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/limits.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/unaligned.h>

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

#define MPL3115_STATUS 0x00
#define MPL3115_OUT_PRESS 0x01 /* MSB first, 20 bit */
#define MPL3115_OUT_TEMP 0x04 /* MSB first, 12 bit */
#define MPL3115_WHO_AM_I 0x0c
#define MPL3115_INT_SOURCE 0x12
#define MPL3115_PT_DATA_CFG 0x13
#define MPL3115_PRESS_TGT 0x16 /* MSB first, 16 bit */
#define MPL3115_TEMP_TGT 0x18
#define MPL3115_CTRL_REG1 0x26
#define MPL3115_CTRL_REG2 0x27
#define MPL3115_CTRL_REG3 0x28
#define MPL3115_CTRL_REG4 0x29
#define MPL3115_CTRL_REG5 0x2a

#define MPL3115_DEVICE_ID 0xc4

#define MPL3115_STATUS_PRESS_RDY BIT(2)
#define MPL3115_STATUS_TEMP_RDY BIT(1)

#define MPL3115_INT_SRC_DRDY BIT(7)
#define MPL3115_INT_SRC_PTH BIT(3)
#define MPL3115_INT_SRC_TTH BIT(2)

#define MPL3115_PT_DATA_EVENT_ALL GENMASK(2, 0)

#define MPL3115_CTRL1_RESET BIT(2) /* software reset */
#define MPL3115_CTRL1_OST BIT(1) /* initiate measurement */
#define MPL3115_CTRL1_ACTIVE BIT(0) /* continuous measurement */
#define MPL3115_CTRL1_OS_258MS GENMASK(5, 4) /* 64x oversampling */

#define MPL3115_CTRL2_ST GENMASK(3, 0)

#define MPL3115_CTRL3_IPOL1 BIT(5)
#define MPL3115_CTRL3_IPOL2 BIT(1)

#define MPL3115_CTRL4_INT_EN_DRDY BIT(7)
#define MPL3115_CTRL4_INT_EN_PTH BIT(3)
#define MPL3115_CTRL4_INT_EN_TTH BIT(2)

#define MPL3115_CTRL5_INT_CFG_DRDY BIT(7)

static const unsigned int mpl3115_samp_freq_table[][2] = {
        { 1,      0 },
        { 0, 500000 },
        { 0, 250000 },
        { 0, 125000 },
        { 0,  62500 },
        { 0,  31250 },
        { 0,  15625 },
        { 0,   7812 },
        { 0,   3906 },
        { 0,   1953 },
        { 0,    976 },
        { 0,    488 },
        { 0,    244 },
        { 0,    122 },
        { 0,     61 },
        { 0,     30 },
};

struct mpl3115_data {
        struct i2c_client *client;
        struct iio_trigger *drdy_trig;
        struct mutex lock;
        u8 ctrl_reg1;
        u8 ctrl_reg4;
};

enum mpl3115_irq_pin {
        MPL3115_IRQ_INT1,
        MPL3115_IRQ_INT2,
};

static int mpl3115_request(struct mpl3115_data *data)
{
        int ret, tries = 15;

        /* trigger measurement */
        ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
                data->ctrl_reg1 | MPL3115_CTRL1_OST);
        if (ret < 0)
                return ret;

        while (tries-- > 0) {
                ret = i2c_smbus_read_byte_data(data->client, MPL3115_CTRL_REG1);
                if (ret < 0)
                        return ret;
                /* wait for data ready, i.e. OST cleared */
                if (!(ret & MPL3115_CTRL1_OST))
                        break;
                msleep(20);
        }

        if (tries < 0) {
                dev_err(&data->client->dev, "data not ready\n");
                return -EIO;
        }

        return 0;
}

static int mpl3115_read_info_raw(struct mpl3115_data *data,
                                 struct iio_chan_spec const *chan, int *val)
{
        int ret;

        switch (chan->type) {
        case IIO_PRESSURE: { /* in 0.25 pascal / LSB */
                u8 press_be24[3];

                guard(mutex)(&data->lock);
                ret = mpl3115_request(data);
                if (ret < 0)
                        return ret;

                ret = i2c_smbus_read_i2c_block_data(data->client,
                                                    MPL3115_OUT_PRESS,
                                                    sizeof(press_be24),
                                                    press_be24);
                if (ret < 0)
                        return ret;

                /*
                 * The pressure channel shift is applied in the case where the
                 * data (24-bit big endian) is read into a 32-bit buffer. Here
                 * the data is stored in a 24-bit buffer, so the shift is 4.
                 */
                *val = get_unaligned_be24(press_be24) >> 4;
                return IIO_VAL_INT;
        }
        case IIO_TEMP: { /* in 0.0625 celsius / LSB */
                __be16 tmp;

                guard(mutex)(&data->lock);
                ret = mpl3115_request(data);
                if (ret < 0)
                        return ret;

                ret = i2c_smbus_read_i2c_block_data(data->client,
                                                    MPL3115_OUT_TEMP,
                                                    2, (u8 *) &tmp);
                if (ret < 0)
                        return ret;

                *val = sign_extend32(be16_to_cpu(tmp) >> chan->scan_type.shift,
                                     chan->scan_type.realbits - 1);
                return IIO_VAL_INT;
        }
        default:
                return -EINVAL;
        }
}

static int mpl3115_read_raw(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan,
                            int *val, int *val2, long mask)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (!iio_device_claim_direct(indio_dev))
                        return -EBUSY;

                ret = mpl3115_read_info_raw(data, chan, val);
                iio_device_release_direct(indio_dev);
                return ret;

        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {
                case IIO_PRESSURE:
                        *val = 0;
                        *val2 = 250; /* want kilopascal */
                        return IIO_VAL_INT_PLUS_MICRO;
                case IIO_TEMP:
                        *val = 0;
                        *val2 = 62500;
                        return IIO_VAL_INT_PLUS_MICRO;
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_SAMP_FREQ:
                ret = i2c_smbus_read_byte_data(data->client, MPL3115_CTRL_REG2);
                if (ret < 0)
                        return ret;

                ret = FIELD_GET(MPL3115_CTRL2_ST, ret);

                *val = mpl3115_samp_freq_table[ret][0];
                *val2 = mpl3115_samp_freq_table[ret][1];
                return IIO_VAL_INT_PLUS_MICRO;
        }
        return -EINVAL;
}

static int mpl3115_read_avail(struct iio_dev *indio_dev,
                              struct iio_chan_spec const *chan,
                              const int **vals, int *type, int *length,
                              long mask)
{
        if (mask != IIO_CHAN_INFO_SAMP_FREQ)
                return -EINVAL;

        *type = IIO_VAL_INT_PLUS_MICRO;
        *length = ARRAY_SIZE(mpl3115_samp_freq_table) * 2;
        *vals = (int *)mpl3115_samp_freq_table;
        return IIO_AVAIL_LIST;
}

static int mpl3115_write_raw(struct iio_dev *indio_dev,
                             const struct iio_chan_spec *chan,
                             int val, int val2, long mask)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        int i, ret;

        if (mask != IIO_CHAN_INFO_SAMP_FREQ)
                return -EINVAL;

        for (i = 0; i < ARRAY_SIZE(mpl3115_samp_freq_table); i++)
                if (val == mpl3115_samp_freq_table[i][0] &&
                    val2 == mpl3115_samp_freq_table[i][1])
                        break;

        if (i == ARRAY_SIZE(mpl3115_samp_freq_table))
                return -EINVAL;

        if (!iio_device_claim_direct(indio_dev))
                return -EBUSY;

        ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG2,
                                        FIELD_PREP(MPL3115_CTRL2_ST, i));
        iio_device_release_direct(indio_dev);
        return ret;
}

static int mpl3115_fill_trig_buffer(struct iio_dev *indio_dev, u8 *buffer)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        int ret, pos = 0;

        if (!(data->ctrl_reg1 & MPL3115_CTRL1_ACTIVE)) {
                ret = mpl3115_request(data);
                if (ret < 0)
                        return ret;
        }

        if (test_bit(0, indio_dev->active_scan_mask)) {
                ret = i2c_smbus_read_i2c_block_data(data->client,
                        MPL3115_OUT_PRESS, 3, &buffer[pos]);
                if (ret < 0)
                        return ret;
                pos += 4;
        }

        if (test_bit(1, indio_dev->active_scan_mask)) {
                ret = i2c_smbus_read_i2c_block_data(data->client,
                        MPL3115_OUT_TEMP, 2, &buffer[pos]);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static irqreturn_t mpl3115_trigger_handler(int irq, void *p)
{
        struct iio_poll_func *pf = p;
        struct iio_dev *indio_dev = pf->indio_dev;
        struct mpl3115_data *data = iio_priv(indio_dev);
        /*
         * 32-bit channel + 16-bit channel + padding + ts
         * Note that it is possible for only one of the first 2
         * channels to be enabled. If that happens, the first element
         * of the buffer may be either 16 or 32-bits.  As such we cannot
         * use a simple structure definition to express this data layout.
         */
        u8 buffer[16] __aligned(8) = { };
        int ret;

        mutex_lock(&data->lock);
        ret = mpl3115_fill_trig_buffer(indio_dev, buffer);
        mutex_unlock(&data->lock);
        if (ret)
                goto done;

        iio_push_to_buffers_with_ts(indio_dev, buffer, sizeof(buffer),
                                    iio_get_time_ns(indio_dev));

done:
        iio_trigger_notify_done(indio_dev->trig);
        return IRQ_HANDLED;
}

static const struct iio_event_spec mpl3115_temp_press_event[] = {
        {
                .type = IIO_EV_TYPE_THRESH,
                .dir = IIO_EV_DIR_RISING,
                .mask_separate = BIT(IIO_EV_INFO_ENABLE) |
                                 BIT(IIO_EV_INFO_VALUE),
        },
};

static const struct iio_chan_spec mpl3115_channels[] = {
        {
                .type = IIO_PRESSURE,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
                .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 = 0,
                .scan_type = {
                        .sign = 'u',
                        .realbits = 20,
                        .storagebits = 32,
                        .shift = 12,
                        .endianness = IIO_BE,
                },
                .event_spec = mpl3115_temp_press_event,
                .num_event_specs = ARRAY_SIZE(mpl3115_temp_press_event),
        },
        {
                .type = IIO_TEMP,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
                .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 = 1,
                .scan_type = {
                        .sign = 's',
                        .realbits = 12,
                        .storagebits = 16,
                        .shift = 4,
                        .endianness = IIO_BE,
                },
                .event_spec = mpl3115_temp_press_event,
                .num_event_specs = ARRAY_SIZE(mpl3115_temp_press_event),
        },
        IIO_CHAN_SOFT_TIMESTAMP(2),
};

static irqreturn_t mpl3115_interrupt_handler(int irq, void *private)
{
        struct iio_dev *indio_dev = private;
        struct mpl3115_data *data = iio_priv(indio_dev);
        int ret;
        u8 val_press[3];
        __be16 val_temp;

        ret = i2c_smbus_read_byte_data(data->client, MPL3115_INT_SOURCE);
        if (ret < 0)
                return IRQ_HANDLED;

        if (!(ret & (MPL3115_INT_SRC_TTH | MPL3115_INT_SRC_PTH |
                     MPL3115_INT_SRC_DRDY)))
                return IRQ_NONE;

        if (ret & MPL3115_INT_SRC_DRDY)
                iio_trigger_poll_nested(data->drdy_trig);

        if (ret & MPL3115_INT_SRC_PTH) {
                iio_push_event(indio_dev,
                               IIO_UNMOD_EVENT_CODE(IIO_PRESSURE, 0,
                                                    IIO_EV_TYPE_THRESH,
                                                    IIO_EV_DIR_RISING),
                                                    iio_get_time_ns(indio_dev));

                /* Reset the SRC_PTH bit in INT_SOURCE */
                i2c_smbus_read_i2c_block_data(data->client,
                                              MPL3115_OUT_PRESS,
                                              sizeof(val_press), val_press);
        }

        if (ret & MPL3115_INT_SRC_TTH) {
                iio_push_event(indio_dev,
                               IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,
                                                    IIO_EV_TYPE_THRESH,
                                                    IIO_EV_DIR_RISING),
                                                    iio_get_time_ns(indio_dev));

                /* Reset the SRC_TTH bit in INT_SOURCE */
                i2c_smbus_read_i2c_block_data(data->client,
                                              MPL3115_OUT_TEMP,
                                              sizeof(val_temp),
                                              (u8 *)&val_temp);
        }

        return IRQ_HANDLED;
}

static int mpl3115_config_interrupt(struct mpl3115_data *data,
                                    u8 ctrl_reg1, u8 ctrl_reg4)
{
        int ret;

        ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
                                        ctrl_reg1);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG4,
                                        ctrl_reg4);
        if (ret < 0)
                goto reg1_cleanup;

        data->ctrl_reg1 = ctrl_reg1;
        data->ctrl_reg4 = ctrl_reg4;

        return 0;

reg1_cleanup:
        i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
                                  data->ctrl_reg1);
        return ret;
}

static int mpl3115_set_trigger_state(struct iio_trigger *trig, bool state)
{
        struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
        struct mpl3115_data *data = iio_priv(indio_dev);
        u8 ctrl_reg1, ctrl_reg4;

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

        ctrl_reg1 = data->ctrl_reg1;
        ctrl_reg4 = data->ctrl_reg4;

        if (state) {
                ctrl_reg1 |= MPL3115_CTRL1_ACTIVE;
                ctrl_reg4 |= MPL3115_CTRL4_INT_EN_DRDY;
        } else {
                ctrl_reg4 &= ~MPL3115_CTRL4_INT_EN_DRDY;

                if (!ctrl_reg4)
                        ctrl_reg1 &= ~MPL3115_CTRL1_ACTIVE;
        }

        return mpl3115_config_interrupt(data, ctrl_reg1, ctrl_reg4);
}

static const struct iio_trigger_ops mpl3115_trigger_ops = {
        .set_trigger_state = mpl3115_set_trigger_state,
};

static int mpl3115_read_event_config(struct iio_dev *indio_dev,
                                     const struct iio_chan_spec *chan,
                                     enum iio_event_type type,
                                     enum iio_event_direction dir)
{
        struct mpl3115_data *data = iio_priv(indio_dev);

        if (chan->type == IIO_PRESSURE)
                return !!(data->ctrl_reg4 & MPL3115_CTRL4_INT_EN_PTH);

        if (chan->type == IIO_TEMP)
                return !!(data->ctrl_reg4 & MPL3115_CTRL4_INT_EN_TTH);

        return -EINVAL;
}

static int mpl3115_write_event_config(struct iio_dev *indio_dev,
                                      const struct iio_chan_spec *chan,
                                      enum iio_event_type type,
                                      enum iio_event_direction dir,
                                      bool state)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        u8 int_en_mask;
        u8 ctrl_reg1, ctrl_reg4;

        switch (chan->type) {
        case IIO_PRESSURE:
                int_en_mask = MPL3115_CTRL4_INT_EN_PTH;
                break;
        case IIO_TEMP:
                int_en_mask = MPL3115_CTRL4_INT_EN_TTH;
                break;
        default:
                return -EINVAL;
        }

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

        ctrl_reg1 = data->ctrl_reg1;
        ctrl_reg4 = data->ctrl_reg4;

        if (state) {
                ctrl_reg1 |= MPL3115_CTRL1_ACTIVE;
                ctrl_reg4 |= int_en_mask;
        } else {
                ctrl_reg4 &= ~int_en_mask;

                if (!ctrl_reg4)
                        ctrl_reg1 &= ~MPL3115_CTRL1_ACTIVE;
        }

        return mpl3115_config_interrupt(data, ctrl_reg1, ctrl_reg4);
}

static int mpl3115_read_thresh(struct iio_dev *indio_dev,
                               const struct iio_chan_spec *chan,
                               enum iio_event_type type,
                               enum iio_event_direction dir,
                               enum iio_event_info info,
                               int *val, int *val2)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        int ret;
        __be16 press_tgt;

        if (info != IIO_EV_INFO_VALUE)
                return -EINVAL;

        switch (chan->type) {
        case IIO_PRESSURE:
                ret = i2c_smbus_read_i2c_block_data(data->client,
                                                    MPL3115_PRESS_TGT,
                                                    sizeof(press_tgt),
                                                    (u8 *)&press_tgt);
                if (ret < 0)
                        return ret;

                /*
                 * Target value for the pressure is 16-bit unsigned value,
                 * expressed in 2 Pa units
                 */
                *val = be16_to_cpu(press_tgt) << 1;

                return IIO_VAL_INT;
        case IIO_TEMP:
                ret = i2c_smbus_read_byte_data(data->client, MPL3115_TEMP_TGT);
                if (ret < 0)
                        return ret;

                /* Target value for the temperature is 8-bit 2's complement */
                *val = sign_extend32(ret, 7);

                return IIO_VAL_INT;
        default:
                return -EINVAL;
        }
}

static int mpl3115_write_thresh(struct iio_dev *indio_dev,
                                const struct iio_chan_spec *chan,
                                enum iio_event_type type,
                                enum iio_event_direction dir,
                                enum iio_event_info info,
                                int val, int val2)
{
        struct mpl3115_data *data = iio_priv(indio_dev);
        __be16 press_tgt;

        if (info != IIO_EV_INFO_VALUE)
                return -EINVAL;

        switch (chan->type) {
        case IIO_PRESSURE:
                val >>= 1;

                if (val < 0 || val > U16_MAX)
                        return -EINVAL;

                press_tgt = cpu_to_be16(val);

                return i2c_smbus_write_i2c_block_data(data->client,
                                                      MPL3115_PRESS_TGT,
                                                      sizeof(press_tgt),
                                                      (u8 *)&press_tgt);
        case IIO_TEMP:
                if (val < S8_MIN || val > S8_MAX)
                        return -EINVAL;

                return i2c_smbus_write_byte_data(data->client,
                                                 MPL3115_TEMP_TGT, val);
        default:
                return -EINVAL;
        }
}

static const struct iio_info mpl3115_info = {
        .read_raw = &mpl3115_read_raw,
        .read_avail = &mpl3115_read_avail,
        .write_raw = &mpl3115_write_raw,
        .read_event_config = mpl3115_read_event_config,
        .write_event_config = mpl3115_write_event_config,
        .read_event_value = mpl3115_read_thresh,
        .write_event_value = mpl3115_write_thresh,
};

static int mpl3115_trigger_probe(struct mpl3115_data *data,
                                 struct iio_dev *indio_dev)
{
        struct fwnode_handle *fwnode = dev_fwnode(&data->client->dev);
        int ret, irq, irq_type, irq_pin = MPL3115_IRQ_INT1;

        irq = fwnode_irq_get_byname(fwnode, "INT1");
        if (irq < 0) {
                irq = fwnode_irq_get_byname(fwnode, "INT2");
                if (irq < 0)
                        return 0;

                irq_pin = MPL3115_IRQ_INT2;
        }

        irq_type = irq_get_trigger_type(irq);
        if (irq_type != IRQF_TRIGGER_RISING && irq_type != IRQF_TRIGGER_FALLING)
                return -EINVAL;

        ret = i2c_smbus_write_byte_data(data->client, MPL3115_PT_DATA_CFG,
                                        MPL3115_PT_DATA_EVENT_ALL);
        if (ret < 0)
                return ret;

        if (irq_pin == MPL3115_IRQ_INT1) {
                ret = i2c_smbus_write_byte_data(data->client,
                                                MPL3115_CTRL_REG5,
                                                MPL3115_CTRL5_INT_CFG_DRDY);
                if (ret)
                        return ret;

                if (irq_type == IRQF_TRIGGER_RISING) {
                        ret = i2c_smbus_write_byte_data(data->client,
                                                        MPL3115_CTRL_REG3,
                                                        MPL3115_CTRL3_IPOL1);
                        if (ret)
                                return ret;
                }
        } else if (irq_type == IRQF_TRIGGER_RISING) {
                ret = i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG3,
                                                MPL3115_CTRL3_IPOL2);
                if (ret)
                        return ret;
        }

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

        data->drdy_trig->ops = &mpl3115_trigger_ops;
        iio_trigger_set_drvdata(data->drdy_trig, indio_dev);

        ret = devm_request_threaded_irq(&data->client->dev, irq, NULL,
                                        mpl3115_interrupt_handler,
                                        IRQF_ONESHOT,
                                        "mpl3115_irq", indio_dev);
        if (ret)
                return ret;

        ret = devm_iio_trigger_register(&data->client->dev, data->drdy_trig);
        if (ret)
                return ret;

        indio_dev->trig = iio_trigger_get(data->drdy_trig);

        return 0;
}

static int mpl3115_probe(struct i2c_client *client)
{
        const struct i2c_device_id *id = i2c_client_get_device_id(client);
        struct mpl3115_data *data;
        struct iio_dev *indio_dev;
        int ret;

        ret = i2c_smbus_read_byte_data(client, MPL3115_WHO_AM_I);
        if (ret < 0)
                return ret;
        if (ret != MPL3115_DEVICE_ID)
                return -ENODEV;

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

        data = iio_priv(indio_dev);
        data->client = client;
        mutex_init(&data->lock);

        i2c_set_clientdata(client, indio_dev);
        indio_dev->info = &mpl3115_info;
        indio_dev->name = id->name;
        indio_dev->modes = INDIO_DIRECT_MODE;
        indio_dev->channels = mpl3115_channels;
        indio_dev->num_channels = ARRAY_SIZE(mpl3115_channels);

        /* software reset, I2C transfer is aborted (fails) */
        i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
                MPL3115_CTRL1_RESET);
        msleep(50);

        data->ctrl_reg1 = MPL3115_CTRL1_OS_258MS;
        ret = i2c_smbus_write_byte_data(client, MPL3115_CTRL_REG1,
                data->ctrl_reg1);
        if (ret < 0)
                return ret;

        ret = mpl3115_trigger_probe(data, indio_dev);
        if (ret)
                return ret;

        ret = iio_triggered_buffer_setup(indio_dev, NULL,
                mpl3115_trigger_handler, NULL);
        if (ret < 0)
                return ret;

        ret = iio_device_register(indio_dev);
        if (ret < 0)
                goto buffer_cleanup;
        return 0;

buffer_cleanup:
        iio_triggered_buffer_cleanup(indio_dev);
        return ret;
}

static int mpl3115_standby(struct mpl3115_data *data)
{
        return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
                data->ctrl_reg1 & ~MPL3115_CTRL1_ACTIVE);
}

static void mpl3115_remove(struct i2c_client *client)
{
        struct iio_dev *indio_dev = i2c_get_clientdata(client);

        iio_device_unregister(indio_dev);
        iio_triggered_buffer_cleanup(indio_dev);
        mpl3115_standby(iio_priv(indio_dev));
}

static int mpl3115_suspend(struct device *dev)
{
        return mpl3115_standby(iio_priv(i2c_get_clientdata(
                to_i2c_client(dev))));
}

static int mpl3115_resume(struct device *dev)
{
        struct mpl3115_data *data = iio_priv(i2c_get_clientdata(
                to_i2c_client(dev)));

        return i2c_smbus_write_byte_data(data->client, MPL3115_CTRL_REG1,
                data->ctrl_reg1);
}

static DEFINE_SIMPLE_DEV_PM_OPS(mpl3115_pm_ops, mpl3115_suspend,
                                mpl3115_resume);

static const struct i2c_device_id mpl3115_id[] = {
        { "mpl3115" },
        { }
};
MODULE_DEVICE_TABLE(i2c, mpl3115_id);

static const struct of_device_id mpl3115_of_match[] = {
        { .compatible = "fsl,mpl3115" },
        { }
};
MODULE_DEVICE_TABLE(of, mpl3115_of_match);

static struct i2c_driver mpl3115_driver = {
        .driver = {
                .name   = "mpl3115",
                .of_match_table = mpl3115_of_match,
                .pm     = pm_sleep_ptr(&mpl3115_pm_ops),
        },
        .probe = mpl3115_probe,
        .remove = mpl3115_remove,
        .id_table = mpl3115_id,
};
module_i2c_driver(mpl3115_driver);

MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("Freescale MPL3115 pressure/temperature driver");
MODULE_LICENSE("GPL");