/*
 * sca3000_core.c -- support VTI sca3000 series accelerometers via SPI
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk>
 *
 * See industrialio/accels/sca3000.h for comments.
 */

#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/sysfs.h>
#include "../iio.h"
#include "../sysfs.h"
#include "../ring_generic.h"

#include "accel.h"
#include "sca3000.h"

enum sca3000_variant {
        d01,
        d03,
        e02,
        e04,
        e05,
        l01,
};

/* Note where option modes are not defined, the chip simply does not
 * support any.
 * Other chips in the sca3000 series use i2c and are not included here.
 *
 * Some of these devices are only listed in the family data sheet and
 * do not actually appear to be available.
 */
static const struct sca3000_chip_info sca3000_spi_chip_info_tbl[] = {
        {
                .name = "sca3000-d01",
                .temp_output = true,
                .measurement_mode_freq = 250,
                .option_mode_1 = SCA3000_OP_MODE_BYPASS,
                .option_mode_1_freq = 250,
        }, {
                /* No data sheet available - may be the same as the 3100-d03?*/
                .name = "sca3000-d03",
                .temp_output = true,
        }, {
                .name = "sca3000-e02",
                .measurement_mode_freq = 125,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 63,
        }, {
                .name = "sca3000-e04",
                .measurement_mode_freq = 100,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 50,
                .option_mode_2 = SCA3000_OP_MODE_WIDE,
                .option_mode_2_freq = 400,
        }, {
                .name = "sca3000-e05",
                .measurement_mode_freq = 200,
                .option_mode_1 = SCA3000_OP_MODE_NARROW,
                .option_mode_1_freq = 50,
                .option_mode_2 = SCA3000_OP_MODE_WIDE,
                .option_mode_2_freq = 400,
        }, {
                /* No data sheet available.
                 * Frequencies are unknown.
                 */
                .name = "sca3000-l01",
                .temp_output = true,
                .option_mode_1 = SCA3000_OP_MODE_BYPASS,
        },
};


int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val)
{
        struct spi_transfer xfer = {
                .bits_per_word = 8,
                .len = 2,
                .cs_change = 1,
                .tx_buf = st->tx,
        };
        struct spi_message msg;

        st->tx[0] = SCA3000_WRITE_REG(address);
        st->tx[1] = val;
        spi_message_init(&msg);
        spi_message_add_tail(&xfer, &msg);

        return spi_sync(st->us, &msg);
}

int sca3000_read_data(struct sca3000_state *st,
                      uint8_t reg_address_high,
                      u8 **rx_p,
                      int len)
{
        int ret;
        struct spi_message msg;
        struct spi_transfer xfer = {
                .bits_per_word = 8,
                .len = len + 1,
                .cs_change = 1,
                .tx_buf = st->tx,
        };

        *rx_p = kmalloc(len + 1, GFP_KERNEL);
        if (*rx_p == NULL) {
                ret = -ENOMEM;
                goto error_ret;
        }
        xfer.rx_buf = *rx_p;
        st->tx[0] = SCA3000_READ_REG(reg_address_high);
        spi_message_init(&msg);
        spi_message_add_tail(&xfer, &msg);

        ret = spi_sync(st->us, &msg);

        if (ret) {
                dev_err(get_device(&st->us->dev), "problem reading register");
                goto error_free_rx;
        }

        return 0;
error_free_rx:
        kfree(*rx_p);
error_ret:
        return ret;

}
/**
 * sca3000_reg_lock_on() test if the ctrl register lock is on
 *
 * Lock must be held.
 **/
static int sca3000_reg_lock_on(struct sca3000_state *st)
{
        u8 *rx;
        int ret;

        ret = sca3000_read_data(st, SCA3000_REG_ADDR_STATUS, &rx, 1);

        if (ret < 0)
                return ret;
        ret = !(rx[1] & SCA3000_LOCKED);
        kfree(rx);

        return ret;
}

/**
 * __sca3000_unlock_reg_lock() unlock the control registers
 *
 * Note the device does not appear to support doing this in a single transfer.
 * This should only ever be used as part of ctrl reg read.
 * Lock must be held before calling this
 **/
static int __sca3000_unlock_reg_lock(struct sca3000_state *st)
{
        struct spi_message msg;
        struct spi_transfer xfer[3] = {
                {
                        .bits_per_word = 8,
                        .len = 2,
                        .cs_change = 1,
                        .tx_buf = st->tx,
                }, {
                        .bits_per_word = 8,
                        .len = 2,
                        .cs_change = 1,
                        .tx_buf = st->tx + 2,
                }, {
                        .bits_per_word = 8,
                        .len = 2,
                        .cs_change = 1,
                        .tx_buf = st->tx + 4,
                },
        };
        st->tx[0] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
        st->tx[1] = 0x00;
        st->tx[2] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
        st->tx[3] = 0x50;
        st->tx[4] = SCA3000_WRITE_REG(SCA3000_REG_ADDR_UNLOCK);
        st->tx[5] = 0xA0;
        spi_message_init(&msg);
        spi_message_add_tail(&xfer[0], &msg);
        spi_message_add_tail(&xfer[1], &msg);
        spi_message_add_tail(&xfer[2], &msg);

        return spi_sync(st->us, &msg);
}

/**
 * sca3000_write_ctrl_reg() write to a lock protect ctrl register
 * @sel: selects which registers we wish to write to
 * @val: the value to be written
 *
 * Certain control registers are protected against overwriting by the lock
 * register and use a shared write address. This function allows writing of
 * these registers.
 * Lock must be held.
 **/
static int sca3000_write_ctrl_reg(struct sca3000_state *st,
                                  uint8_t sel,
                                  uint8_t val)
{

        int ret;

        ret = sca3000_reg_lock_on(st);
        if (ret < 0)
                goto error_ret;
        if (ret) {
                ret = __sca3000_unlock_reg_lock(st);
                if (ret)
                        goto error_ret;
        }

        /* Set the control select register */
        ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, sel);
        if (ret)
                goto error_ret;

        /* Write the actual value into the register */
        ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_DATA, val);

error_ret:
        return ret;
}

/* Crucial that lock is called before calling this */
/**
 * sca3000_read_ctrl_reg() read from lock protected control register.
 *
 * Lock must be held.
 **/
static int sca3000_read_ctrl_reg(struct sca3000_state *st,
                                 u8 ctrl_reg,
                                 u8 **rx_p)
{
        int ret;

        ret = sca3000_reg_lock_on(st);
        if (ret < 0)
                goto error_ret;
        if (ret) {
                ret = __sca3000_unlock_reg_lock(st);
                if (ret)
                        goto error_ret;
        }
        /* Set the control select register */
        ret = sca3000_write_reg(st, SCA3000_REG_ADDR_CTRL_SEL, ctrl_reg);
        if (ret)
                goto error_ret;
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_CTRL_DATA, rx_p, 1);

error_ret:
        return ret;
}

#ifdef SCA3000_DEBUG
/**
 * sca3000_check_status() check the status register
 *
 * Only used for debugging purposes
 **/
static int sca3000_check_status(struct device *dev)
{
        u8 *rx;
        int ret;
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_STATUS, &rx, 1);
        if (ret < 0)
                goto error_ret;
        if (rx[1] & SCA3000_EEPROM_CS_ERROR)
                dev_err(dev, "eeprom error \n");
        if (rx[1] & SCA3000_SPI_FRAME_ERROR)
                dev_err(dev, "Previous SPI Frame was corrupt\n");
        kfree(rx);

error_ret:
        mutex_unlock(&st->lock);
        return ret;
}
#endif /* SCA3000_DEBUG */

/**
 * sca3000_read_13bit_signed() sysfs interface to read 13 bit signed registers
 *
 * These are described as signed 12 bit on the data sheet, which appears
 * to be a conventional 2's complement 13 bit.
 **/
static ssize_t sca3000_read_13bit_signed(struct device *dev,
                                         struct device_attribute *attr,
                                         char *buf)
{
        int len = 0, ret;
        int val;
        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
        u8 *rx;
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, this_attr->address, &rx, 2);
        if (ret < 0)
                goto error_ret;
        val = sca3000_13bit_convert(rx[1], rx[2]);
        len += sprintf(buf + len, "%d\n", val);
        kfree(rx);
error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}


static ssize_t sca3000_show_name(struct device *dev,
                                 struct device_attribute *attr,
                                 char *buf)
{
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct sca3000_state *st = dev_info->dev_data;
        return sprintf(buf, "%s\n", st->info->name);
}
/**
 * sca3000_show_reg() - sysfs interface to read the chip revision number
 **/
static ssize_t sca3000_show_rev(struct device *dev,
                                struct device_attribute *attr,
                                char *buf)
{
        int len = 0, ret;
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct sca3000_state *st = dev_info->dev_data;

        u8 *rx;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_REVID, &rx, 1);
        if (ret < 0)
                goto error_ret;
        len += sprintf(buf + len,
                       "major=%d, minor=%d\n",
                       rx[1] & SCA3000_REVID_MAJOR_MASK,
                       rx[1] & SCA3000_REVID_MINOR_MASK);
        kfree(rx);

error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/**
 * sca3000_show_available_measurement_modes() display available modes
 *
 * This is all read from chip specific data in the driver. Not all
 * of the sca3000 series support modes other than normal.
 **/
static ssize_t
sca3000_show_available_measurement_modes(struct device *dev,
                                         struct device_attribute *attr,
                                         char *buf)
{
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct sca3000_state *st = dev_info->dev_data;
        int len = 0;

        len += sprintf(buf + len, "0 - normal mode");
        switch (st->info->option_mode_1) {
        case SCA3000_OP_MODE_NARROW:
                len += sprintf(buf + len, ", 1 - narrow mode");
                break;
        case SCA3000_OP_MODE_BYPASS:
                len += sprintf(buf + len, ", 1 - bypass mode");
                break;
        };
        switch (st->info->option_mode_2) {
        case SCA3000_OP_MODE_WIDE:
                len += sprintf(buf + len, ", 2 - wide mode");
                break;
        }
        /* always supported */
        len += sprintf(buf + len, " 3 - motion detection \n");

        return len;
}

/**
 * sca3000_show_measurmenet_mode() sysfs read of current mode
 **/
static ssize_t
sca3000_show_measurement_mode(struct device *dev,
                              struct device_attribute *attr,
                              char *buf)
{
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct sca3000_state *st = dev_info->dev_data;
        int len = 0, ret;
        u8 *rx;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto error_ret;
        /* mask bottom 2 bits - only ones that are relevant */
        rx[1] &= 0x03;
        switch (rx[1]) {
        case SCA3000_MEAS_MODE_NORMAL:
                len += sprintf(buf + len, "0 - normal mode\n");
                break;
        case SCA3000_MEAS_MODE_MOT_DET:
                len += sprintf(buf + len, "3 - motion detection\n");
                break;
        case SCA3000_MEAS_MODE_OP_1:
                switch (st->info->option_mode_1) {
                case SCA3000_OP_MODE_NARROW:
                        len += sprintf(buf + len, "1 - narrow mode\n");
                        break;
                case SCA3000_OP_MODE_BYPASS:
                        len += sprintf(buf + len, "1 - bypass mode\n");
                        break;
                };
                break;
        case SCA3000_MEAS_MODE_OP_2:
                switch (st->info->option_mode_2) {
                case SCA3000_OP_MODE_WIDE:
                        len += sprintf(buf + len, "2 - wide mode\n");
                        break;
                }
                break;
        };

error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/**
 * sca3000_store_measurement_mode() set the current mode
 **/
static ssize_t
sca3000_store_measurement_mode(struct device *dev,
                               struct device_attribute *attr,
                               const char *buf,
                               size_t len)
{
        struct iio_dev *dev_info = dev_get_drvdata(dev);
        struct sca3000_state *st = dev_info->dev_data;
        int ret;
        u8 *rx;
        int mask = 0x03;
        long val;

        mutex_lock(&st->lock);
        ret = strict_strtol(buf, 10, &val);
        if (ret)
                goto error_ret;
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto error_ret;
        rx[1] &= ~mask;
        rx[1] |= (val & mask);
        ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE, rx[1]);
        if (ret)
                goto error_free_rx;
        mutex_unlock(&st->lock);

        return len;

error_free_rx:
        kfree(rx);
error_ret:
        mutex_unlock(&st->lock);

        return ret;
}


/* Not even vaguely standard attributes so defined here rather than
 * in the relevant IIO core headers
 */
static IIO_DEVICE_ATTR(available_measurement_modes, S_IRUGO,
                       sca3000_show_available_measurement_modes,
                       NULL, 0);

static IIO_DEVICE_ATTR(measurement_mode, S_IRUGO | S_IWUSR,
                       sca3000_show_measurement_mode,
                       sca3000_store_measurement_mode,
                       0);

/* More standard attributes */

static IIO_DEV_ATTR_NAME(sca3000_show_name);
static IIO_DEV_ATTR_REV(sca3000_show_rev);

static IIO_DEV_ATTR_ACCEL_X(sca3000_read_13bit_signed,
                            SCA3000_REG_ADDR_X_MSB);
static IIO_DEV_ATTR_ACCEL_Y(sca3000_read_13bit_signed,
                            SCA3000_REG_ADDR_Y_MSB);
static IIO_DEV_ATTR_ACCEL_Z(sca3000_read_13bit_signed,
                            SCA3000_REG_ADDR_Z_MSB);


/**
 * sca3000_read_av_freq() sysfs function to get available frequencies
 *
 * The later modes are only relevant to the ring buffer - and depend on current
 * mode. Note that data sheet gives rather wide tolerances for these so integer
 * division will give good enough answer and not all chips have them specified
 * at all.
 **/
static ssize_t sca3000_read_av_freq(struct device *dev,
                             struct device_attribute *attr,
                             char *buf)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        int len = 0, ret;
        u8 *rx;
        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        mutex_unlock(&st->lock);
        if (ret)
                goto error_ret;
        rx[1] &= 0x03;
        switch (rx[1]) {
        case SCA3000_MEAS_MODE_NORMAL:
                len += sprintf(buf + len, "%d %d %d\n",
                               st->info->measurement_mode_freq,
                               st->info->measurement_mode_freq/2,
                               st->info->measurement_mode_freq/4);
                break;
        case SCA3000_MEAS_MODE_OP_1:
                len += sprintf(buf + len, "%d %d %d\n",
                               st->info->option_mode_1_freq,
                               st->info->option_mode_1_freq/2,
                               st->info->option_mode_1_freq/4);
                break;
        case SCA3000_MEAS_MODE_OP_2:
                len += sprintf(buf + len, "%d %d %d\n",
                               st->info->option_mode_2_freq,
                               st->info->option_mode_2_freq/2,
                               st->info->option_mode_2_freq/4);
                break;
        };
        kfree(rx);
        return len;
error_ret:
        return ret;
}
/**
 * __sca3000_get_base_frequency() obtain mode specific base frequency
 *
 * lock must be held
 **/
static inline int __sca3000_get_base_freq(struct sca3000_state *st,
                                          const struct sca3000_chip_info *info,
                                          int *base_freq)
{
        int ret;
        u8 *rx;

        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto error_ret;
        switch (0x03 & rx[1]) {
        case SCA3000_MEAS_MODE_NORMAL:
                *base_freq = info->measurement_mode_freq;
                break;
        case SCA3000_MEAS_MODE_OP_1:
                *base_freq = info->option_mode_1_freq;
                break;
        case SCA3000_MEAS_MODE_OP_2:
                *base_freq = info->option_mode_2_freq;
                break;
        };
        kfree(rx);
error_ret:
        return ret;
}

/**
 * sca3000_read_frequency() sysfs interface to get the current frequency
 **/
static ssize_t sca3000_read_frequency(struct device *dev,
                               struct device_attribute *attr,
                               char *buf)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        int ret, len = 0, base_freq = 0;
        u8 *rx;
        mutex_lock(&st->lock);
        ret = __sca3000_get_base_freq(st, st->info, &base_freq);
        if (ret)
                goto error_ret_mut;
        ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, &rx);
        mutex_unlock(&st->lock);
        if (ret)
                goto error_ret;
        if (base_freq > 0)
                switch (rx[1]&0x03) {
                case 0x00:
                case 0x03:
                        len = sprintf(buf, "%d\n", base_freq);
                        break;
                case 0x01:
                        len = sprintf(buf, "%d\n", base_freq/2);
                        break;
                case 0x02:
                        len = sprintf(buf, "%d\n", base_freq/4);
                        break;
        };
                        kfree(rx);
        return len;
error_ret_mut:
        mutex_unlock(&st->lock);
error_ret:
        return ret;
}

/**
 * sca3000_set_frequency() sysfs interface to set the current frequency
 **/
static ssize_t sca3000_set_frequency(struct device *dev,
                              struct device_attribute *attr,
                              const char *buf,
                              size_t len)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        int ret, base_freq = 0;
        u8 *rx;
        long val;

        ret = strict_strtol(buf, 10, &val);
        if (ret)
                return ret;

        mutex_lock(&st->lock);
        /* What mode are we in? */
        ret = __sca3000_get_base_freq(st, st->info, &base_freq);
        if (ret)
                goto error_free_lock;

        ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, &rx);
        if (ret)
                goto error_free_lock;
        /* clear the bits */
        rx[1] &= ~0x03;

        if (val == base_freq/2) {
                rx[1] |= SCA3000_OUT_CTRL_BUF_DIV_2;
        } else if (val == base_freq/4) {
                rx[1] |= SCA3000_OUT_CTRL_BUF_DIV_4;
        } else if (val != base_freq) {
                ret = -EINVAL;
                goto error_free_lock;
        }
        ret = sca3000_write_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL, rx[1]);
error_free_lock:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/* Should only really be registered if ring buffer support is compiled in.
 * Does no harm however and doing it right would add a fair bit of complexity
 */
static IIO_DEV_ATTR_AVAIL_SAMP_FREQ(sca3000_read_av_freq);

static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
                              sca3000_read_frequency,
                              sca3000_set_frequency);


/**
 * sca3000_read_temp() sysfs interface to get the temperature when available
 *
* The alignment of data in here is downright odd. See data sheet.
* Converting this into a meaningful value is left to inline functions in
* userspace part of header.
**/
static ssize_t sca3000_read_temp(struct device *dev,
                                 struct device_attribute *attr,
                                 char *buf)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        int len = 0, ret;
        int val;
        u8 *rx;
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_TEMP_MSB, &rx, 2);
        if (ret < 0)
                goto error_ret;
        val = ((rx[1]&0x3F) << 3) | ((rx[2] & 0xE0) >> 5);
        len += sprintf(buf + len, "%d\n", val);
        kfree(rx);

        return len;

error_ret:
        return ret;
}
static IIO_DEV_ATTR_TEMP(sca3000_read_temp);

/**
 * sca3000_show_thresh() sysfs query of a theshold
 **/
static ssize_t sca3000_show_thresh(struct device *dev,
                                   struct device_attribute *attr,
                                   char *buf)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
        int len = 0, ret;
        u8 *rx;

        mutex_lock(&st->lock);
        ret = sca3000_read_ctrl_reg(st,
                                    this_attr->address,
                                    &rx);
        mutex_unlock(&st->lock);
        if (ret)
                return ret;
        len += sprintf(buf + len, "%d\n", rx[1]);
        kfree(rx);

        return len;
}

/**
 * sca3000_write_thresh() sysfs control of threshold
 **/
static ssize_t sca3000_write_thresh(struct device *dev,
                                    struct device_attribute *attr,
                                    const char *buf,
                                    size_t len)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
        int ret;
        long val;

        ret = strict_strtol(buf, 10, &val);
        if (ret)
                return ret;
        mutex_lock(&st->lock);
        ret = sca3000_write_ctrl_reg(st, this_attr->address, val);
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

static IIO_DEV_ATTR_ACCEL_THRESH_X(S_IRUGO | S_IWUSR,
                                   sca3000_show_thresh,
                                   sca3000_write_thresh,
                                   SCA3000_REG_CTRL_SEL_MD_X_TH);
static IIO_DEV_ATTR_ACCEL_THRESH_Y(S_IRUGO | S_IWUSR,
                                   sca3000_show_thresh,
                                   sca3000_write_thresh,
                                   SCA3000_REG_CTRL_SEL_MD_Y_TH);
static IIO_DEV_ATTR_ACCEL_THRESH_Z(S_IRUGO | S_IWUSR,
                                   sca3000_show_thresh,
                                   sca3000_write_thresh,
                                   SCA3000_REG_CTRL_SEL_MD_Z_TH);

static struct attribute *sca3000_attributes[] = {
        &iio_dev_attr_name.dev_attr.attr,
        &iio_dev_attr_revision.dev_attr.attr,
        &iio_dev_attr_accel_x.dev_attr.attr,
        &iio_dev_attr_accel_y.dev_attr.attr,
        &iio_dev_attr_accel_z.dev_attr.attr,
        &iio_dev_attr_thresh_accel_x.dev_attr.attr,
        &iio_dev_attr_thresh_accel_y.dev_attr.attr,
        &iio_dev_attr_thresh_accel_z.dev_attr.attr,
        &iio_dev_attr_available_measurement_modes.dev_attr.attr,
        &iio_dev_attr_measurement_mode.dev_attr.attr,
        &iio_dev_attr_available_sampling_frequency.dev_attr.attr,
        &iio_dev_attr_sampling_frequency.dev_attr.attr,
        NULL,
};

static struct attribute *sca3000_attributes_with_temp[] = {
        &iio_dev_attr_name.dev_attr.attr,
        &iio_dev_attr_revision.dev_attr.attr,
        &iio_dev_attr_accel_x.dev_attr.attr,
        &iio_dev_attr_accel_y.dev_attr.attr,
        &iio_dev_attr_accel_z.dev_attr.attr,
        &iio_dev_attr_thresh_accel_x.dev_attr.attr,
        &iio_dev_attr_thresh_accel_y.dev_attr.attr,
        &iio_dev_attr_thresh_accel_z.dev_attr.attr,
        &iio_dev_attr_available_measurement_modes.dev_attr.attr,
        &iio_dev_attr_measurement_mode.dev_attr.attr,
        &iio_dev_attr_available_sampling_frequency.dev_attr.attr,
        &iio_dev_attr_sampling_frequency.dev_attr.attr,
        /* Only present if temp sensor is */
        &iio_dev_attr_temp.dev_attr.attr,
        NULL,
};

static const struct attribute_group sca3000_attribute_group = {
        .attrs = sca3000_attributes,
};

static const struct attribute_group sca3000_attribute_group_with_temp = {
        .attrs = sca3000_attributes_with_temp,
};

/* RING RELATED interrupt handler */
/* depending on event, push to the ring buffer event chrdev or the event one */

/**
 * sca3000_interrupt_handler_bh() - handling ring and non ring events
 *
 * This function is complicated by the fact that the devices can signify ring
 * and non ring events via the same interrupt line and they can only
 * be distinguished via a read of the relevant status register.
 **/
static void sca3000_interrupt_handler_bh(struct work_struct *work_s)
{
        struct sca3000_state *st
                = container_of(work_s, struct sca3000_state,
                               interrupt_handler_ws);
        u8 *rx;
        int ret;

        /* Could lead if badly timed to an extra read of status reg,
         * but ensures no interrupt is missed.
         */
        enable_irq(st->us->irq);
        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_STATUS,
                                &rx, 1);
        mutex_unlock(&st->lock);
        if (ret)
                goto done;

        sca3000_ring_int_process(rx[1], st->indio_dev->ring);

        if (rx[1] & SCA3000_INT_STATUS_FREE_FALL)
                iio_push_event(st->indio_dev, 0,
                               IIO_EVENT_CODE_FREE_FALL,
                               st->last_timestamp);

        if (rx[1] & SCA3000_INT_STATUS_Y_TRIGGER)
                iio_push_event(st->indio_dev, 0,
                               IIO_EVENT_CODE_ACCEL_Y_HIGH,
                               st->last_timestamp);

        if (rx[1] & SCA3000_INT_STATUS_X_TRIGGER)
                iio_push_event(st->indio_dev, 0,
                               IIO_EVENT_CODE_ACCEL_X_HIGH,
                               st->last_timestamp);

        if (rx[1] & SCA3000_INT_STATUS_Z_TRIGGER)
                iio_push_event(st->indio_dev, 0,
                               IIO_EVENT_CODE_ACCEL_Z_HIGH,
                               st->last_timestamp);

done:
        kfree(rx);
        return;
}

/**
 * sca3000_handler_th() handles all interrupt events from device
 *
 * These devices deploy unified interrupt status registers meaning
 * all interrupts must be handled together
 **/
static int sca3000_handler_th(struct iio_dev *dev_info,
                              int index,
                              s64 timestamp,
                              int no_test)
{
        struct sca3000_state *st = dev_info->dev_data;

        st->last_timestamp = timestamp;
        schedule_work(&st->interrupt_handler_ws);

        return 0;
}

/**
 * sca3000_query_mo_det() is motion detection enabled for this axis
 *
 * First queries if motion detection is enabled and then if this axis is
 * on.
 **/
static ssize_t sca3000_query_mo_det(struct device *dev,
                                    struct device_attribute *attr,
                                    char *buf)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        struct iio_event_attr *this_attr = to_iio_event_attr(attr);
        int ret, len = 0;
        u8 *rx;
        u8 protect_mask = 0x03;

        /* read current value of mode register */
        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto error_ret;

        if ((rx[1]&protect_mask) != SCA3000_MEAS_MODE_MOT_DET)
                len += sprintf(buf + len, "0\n");
        else {
                kfree(rx);
                ret = sca3000_read_ctrl_reg(st,
                                            SCA3000_REG_CTRL_SEL_MD_CTRL,
                                            &rx);
                if (ret)
                        goto error_ret;
                /* only supporting logical or's for now */
                len += sprintf(buf + len, "%d\n",
                               (rx[1] & this_attr->mask) ? 1 : 0);
        }
        kfree(rx);
error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}
/**
 * sca3000_query_free_fall_mode() is free fall mode enabled
 **/
static ssize_t sca3000_query_free_fall_mode(struct device *dev,
                                            struct device_attribute *attr,
                                            char *buf)
{
        int ret, len;
        u8 *rx;
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        mutex_unlock(&st->lock);
        if (ret)
                return ret;
        len = sprintf(buf, "%d\n",
                      !!(rx[1] & SCA3000_FREE_FALL_DETECT));
        kfree(rx);

        return len;
}
/**
 * sca3000_query_ring_int() is the hardware ring status interrupt enabled
 **/
static ssize_t sca3000_query_ring_int(struct device *dev,
                                      struct device_attribute *attr,
                                      char *buf)
{
        struct iio_event_attr *this_attr = to_iio_event_attr(attr);
        int ret, len;
        u8 *rx;
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1);
        mutex_unlock(&st->lock);
        if (ret)
                return ret;
        len = sprintf(buf, "%d\n", (rx[1] & this_attr->mask) ? 1 : 0);
        kfree(rx);

        return len;
}
/**
 * sca3000_set_ring_int() set state of ring status interrupt
 **/
static ssize_t sca3000_set_ring_int(struct device *dev,
                                      struct device_attribute *attr,
                                      const char *buf,
                                      size_t len)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        struct iio_event_attr *this_attr = to_iio_event_attr(attr);

        long val;
        int ret;
        u8 *rx;

        mutex_lock(&st->lock);
        ret = strict_strtol(buf, 10, &val);
        if (ret)
                goto error_ret;
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1);
        if (ret)
                goto error_ret;
        if (val)
                ret = sca3000_write_reg(st,
                                        SCA3000_REG_ADDR_INT_MASK,
                                        rx[1] | this_attr->mask);
        else
                ret = sca3000_write_reg(st,
                                        SCA3000_REG_ADDR_INT_MASK,
                                        rx[1] & ~this_attr->mask);
        kfree(rx);
error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/**
 * sca3000_set_free_fall_mode() simple on off control for free fall int
 *
 * In these chips the free fall detector should send an interrupt if
 * the device falls more than 25cm.  This has not been tested due
 * to fragile wiring.
 **/

static ssize_t sca3000_set_free_fall_mode(struct device *dev,
                                          struct device_attribute *attr,
                                          const char *buf,
                                          size_t len)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        long val;
        int ret;
        u8 *rx;
        u8 protect_mask = SCA3000_FREE_FALL_DETECT;

        mutex_lock(&st->lock);
        ret = strict_strtol(buf, 10, &val);
        if (ret)
                goto error_ret;

        /* read current value of mode register */
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto error_ret;

        /*if off and should be on*/
        if (val && !(rx[1] & protect_mask))
                ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
                                        (rx[1] | SCA3000_FREE_FALL_DETECT));
        /* if on and should be off */
        else if (!val && (rx[1]&protect_mask))
                ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
                                        (rx[1] & ~protect_mask));

        kfree(rx);
error_ret:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/**
 * sca3000_set_mo_det() simple on off control for motion detector
 *
 * This is a per axis control, but enabling any will result in the
 * motion detector unit being enabled.
 * N.B. enabling motion detector stops normal data acquisition.
 * There is a complexity in knowing which mode to return to when
 * this mode is disabled.  Currently normal mode is assumed.
 **/
static ssize_t sca3000_set_mo_det(struct device *dev,
                                  struct device_attribute *attr,
                                  const char *buf,
                                  size_t len)
{
        struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct sca3000_state *st = indio_dev->dev_data;
        struct iio_event_attr *this_attr = to_iio_event_attr(attr);
        long val;
        int ret;
        u8 *rx;
        u8 protect_mask = 0x03;
        ret = strict_strtol(buf, 10, &val);
        if (ret)
                return ret;

        mutex_lock(&st->lock);
        /* First read the motion detector config to find out if
         * this axis is on*/
        ret = sca3000_read_ctrl_reg(st,
                                    SCA3000_REG_CTRL_SEL_MD_CTRL,
                                    &rx);
        if (ret)
                goto exit_point;
        /* Off and should be on */
        if (val && !(rx[1] & this_attr->mask)) {
                ret = sca3000_write_ctrl_reg(st,
                                             SCA3000_REG_CTRL_SEL_MD_CTRL,
                                             rx[1] | this_attr->mask);
                if (ret)
                        goto exit_point_free_rx;
                st->mo_det_use_count++;
        } else if (!val && (rx[1]&this_attr->mask)) {
                ret = sca3000_write_ctrl_reg(st,
                                             SCA3000_REG_CTRL_SEL_MD_CTRL,
                                             rx[1] & ~(this_attr->mask));
                if (ret)
                        goto exit_point_free_rx;
                st->mo_det_use_count--;
        } else /* relies on clean state for device on boot */
                goto exit_point_free_rx;
        kfree(rx);
        /* read current value of mode register */
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);
        if (ret)
                goto exit_point;
        /*if off and should be on*/
        if ((st->mo_det_use_count)
            && ((rx[1]&protect_mask) != SCA3000_MEAS_MODE_MOT_DET))
                ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
                                        (rx[1] & ~protect_mask)
                                        | SCA3000_MEAS_MODE_MOT_DET);
        /* if on and should be off */
        else if (!(st->mo_det_use_count)
                 && ((rx[1]&protect_mask) == SCA3000_MEAS_MODE_MOT_DET))
                ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,
                                        (rx[1] & ~protect_mask));
exit_point_free_rx:
        kfree(rx);
exit_point:
        mutex_unlock(&st->lock);

        return ret ? ret : len;
}

/* Shared event handler for all events as single event status register */
IIO_EVENT_SH(all, &sca3000_handler_th);

/* Free fall detector related event attribute */
IIO_EVENT_ATTR_FREE_FALL_DETECT_SH(iio_event_all,
                                   sca3000_query_free_fall_mode,
                                   sca3000_set_free_fall_mode,
                                   0)

/* Motion detector related event attributes */
IIO_EVENT_ATTR_ACCEL_X_HIGH_SH(iio_event_all,
                               sca3000_query_mo_det,
                               sca3000_set_mo_det,
                               SCA3000_MD_CTRL_OR_X);

IIO_EVENT_ATTR_ACCEL_Y_HIGH_SH(iio_event_all,
                               sca3000_query_mo_det,
                               sca3000_set_mo_det,
                               SCA3000_MD_CTRL_OR_Y);

IIO_EVENT_ATTR_ACCEL_Z_HIGH_SH(iio_event_all,
                               sca3000_query_mo_det,
                               sca3000_set_mo_det,
                               SCA3000_MD_CTRL_OR_Z);

/* Hardware ring buffer related event attributes */
IIO_EVENT_ATTR_RING_50_FULL_SH(iio_event_all,
                               sca3000_query_ring_int,
                               sca3000_set_ring_int,
                               SCA3000_INT_MASK_RING_HALF);

IIO_EVENT_ATTR_RING_75_FULL_SH(iio_event_all,
                               sca3000_query_ring_int,
                               sca3000_set_ring_int,
                               SCA3000_INT_MASK_RING_THREE_QUARTER);

static struct attribute *sca3000_event_attributes[] = {
        &iio_event_attr_free_fall.dev_attr.attr,
        &iio_event_attr_accel_x_high.dev_attr.attr,
        &iio_event_attr_accel_y_high.dev_attr.attr,
        &iio_event_attr_accel_z_high.dev_attr.attr,
        &iio_event_attr_ring_50_full.dev_attr.attr,
        &iio_event_attr_ring_75_full.dev_attr.attr,
        NULL,
};

static struct attribute_group sca3000_event_attribute_group = {
        .attrs = sca3000_event_attributes,
};

/**
 * sca3000_clean_setup() get the device into a predictable state
 *
 * Devices use flash memory to store many of the register values
 * and hence can come up in somewhat unpredictable states.
 * Hence reset everything on driver load.
  **/
static int sca3000_clean_setup(struct sca3000_state *st)
{
        int ret;
        u8 *rx;

        mutex_lock(&st->lock);
        /* Ensure all interrupts have been acknowledged */
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_STATUS, &rx, 1);
        if (ret)
                goto error_ret;
        kfree(rx);

        /* Turn off all motion detection channels */
        ret = sca3000_read_ctrl_reg(st,
                                    SCA3000_REG_CTRL_SEL_MD_CTRL,
                                    &rx);
        if (ret)
                goto error_ret;
        ret = sca3000_write_ctrl_reg(st,
                                     SCA3000_REG_CTRL_SEL_MD_CTRL,
                                     rx[1] & SCA3000_MD_CTRL_PROT_MASK);
        kfree(rx);
        if (ret)
                goto error_ret;

        /* Disable ring buffer */
        sca3000_read_ctrl_reg(st,
                              SCA3000_REG_CTRL_SEL_OUT_CTRL,
                              &rx);
        /* Frequency of ring buffer sampling deliberately restricted to make
         * debugging easier - add control of this later */
        ret = sca3000_write_ctrl_reg(st,
                                     SCA3000_REG_CTRL_SEL_OUT_CTRL,
                                     (rx[1] & SCA3000_OUT_CTRL_PROT_MASK)
                                     | SCA3000_OUT_CTRL_BUF_X_EN
                                     | SCA3000_OUT_CTRL_BUF_Y_EN
                                     | SCA3000_OUT_CTRL_BUF_Z_EN
                                     | SCA3000_OUT_CTRL_BUF_DIV_4);
        kfree(rx);

        if (ret)
                goto error_ret;
        /* Enable interrupts, relevant to mode and set up as active low */
        ret = sca3000_read_data(st,
                          SCA3000_REG_ADDR_INT_MASK,
                          &rx, 1);
        if (ret)
                goto error_ret;
        ret = sca3000_write_reg(st,
                                SCA3000_REG_ADDR_INT_MASK,
                                (rx[1] & SCA3000_INT_MASK_PROT_MASK)
                                | SCA3000_INT_MASK_ACTIVE_LOW);
        kfree(rx);
        if (ret)
                goto error_ret;
        /* Select normal measurement mode, free fall off, ring off */
        /* Ring in 12 bit mode - it is fine to overwrite reserved bits 3,5
         * as that occurs in one of the example on the datasheet */
        ret = sca3000_read_data(st,
                          SCA3000_REG_ADDR_MODE,
                          &rx, 1);
        if (ret)
                goto error_ret;
        ret = sca3000_write_reg(st,
                                SCA3000_REG_ADDR_MODE,
                                (rx[1] & SCA3000_MODE_PROT_MASK));
        kfree(rx);
        st->bpse = 11;

error_ret:
        mutex_unlock(&st->lock);
        return ret;
}

static int __devinit __sca3000_probe(struct spi_device *spi,
                                     enum sca3000_variant variant)
{
        int ret, regdone = 0;
        struct sca3000_state *st;

        st = kzalloc(sizeof(struct sca3000_state), GFP_KERNEL);
        if (st == NULL) {
                ret = -ENOMEM;
                goto error_ret;
        }
        spi_set_drvdata(spi, st);

        st->tx = kmalloc(sizeof(*st->tx)*6, GFP_KERNEL);
        if (st->tx == NULL) {
                ret = -ENOMEM;
                goto error_clear_st;
        }
        st->rx = kmalloc(sizeof(*st->rx)*3, GFP_KERNEL);
        if (st->rx == NULL) {
                ret = -ENOMEM;
                goto error_free_tx;
        }
        st->us = spi;
        mutex_init(&st->lock);
        st->info = &sca3000_spi_chip_info_tbl[variant];

        st->indio_dev = iio_allocate_device();
        if (st->indio_dev == NULL) {
                ret = -ENOMEM;
                goto error_free_rx;
        }

        st->indio_dev->dev.parent = &spi->dev;
        st->indio_dev->num_interrupt_lines = 1;
        st->indio_dev->event_attrs = &sca3000_event_attribute_group;
        if (st->info->temp_output)
                st->indio_dev->attrs = &sca3000_attribute_group_with_temp;
        else
                st->indio_dev->attrs = &sca3000_attribute_group;
        st->indio_dev->dev_data = (void *)(st);
        st->indio_dev->modes = INDIO_DIRECT_MODE;

        sca3000_configure_ring(st->indio_dev);

        ret = iio_device_register(st->indio_dev);
        if (ret < 0)
                goto error_free_dev;
        regdone = 1;
        ret = iio_ring_buffer_register(st->indio_dev->ring);
        if (ret < 0)
                goto error_unregister_dev;
        if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0) {
                INIT_WORK(&st->interrupt_handler_ws,
                          sca3000_interrupt_handler_bh);
                ret = iio_register_interrupt_line(spi->irq,
                                                  st->indio_dev,
                                                  0,
                                                  IRQF_TRIGGER_FALLING,
                                                  "sca3000");
                if (ret)
                        goto error_unregister_ring;
                /* RFC
                 * Probably a common situation.  All interrupts need an ack
                 * and there is only one handler so the complicated list system
                 * is overkill.  At very least a simpler registration method
                 * might be worthwhile.
                 */
                iio_add_event_to_list(iio_event_attr_accel_z_high.listel,
                                            &st->indio_dev
                                            ->interrupts[0]->ev_list);
        }
        sca3000_register_ring_funcs(st->indio_dev);
        ret = sca3000_clean_setup(st);
        if (ret)
                goto error_unregister_interrupt_line;
        return 0;

error_unregister_interrupt_line:
        if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
                iio_unregister_interrupt_line(st->indio_dev, 0);
error_unregister_ring:
        iio_ring_buffer_unregister(st->indio_dev->ring);
error_unregister_dev:
error_free_dev:
        if (regdone)
                iio_device_unregister(st->indio_dev);
        else
                iio_free_device(st->indio_dev);
error_free_rx:
        kfree(st->rx);
error_free_tx:
        kfree(st->tx);
error_clear_st:
        kfree(st);
error_ret:
        return ret;
}

static int sca3000_stop_all_interrupts(struct sca3000_state *st)
{
        int ret;
        u8 *rx;

        mutex_lock(&st->lock);
        ret = sca3000_read_data(st, SCA3000_REG_ADDR_INT_MASK, &rx, 1);
        if (ret)
                goto error_ret;
        ret = sca3000_write_reg(st, SCA3000_REG_ADDR_INT_MASK,
                                (rx[1] & ~(SCA3000_INT_MASK_RING_THREE_QUARTER
                                           | SCA3000_INT_MASK_RING_HALF
                                           | SCA3000_INT_MASK_ALL_INTS)));
error_ret:
        kfree(rx);
        return ret;

}

static int sca3000_remove(struct spi_device *spi)
{
        struct sca3000_state *st =  spi_get_drvdata(spi);
        struct iio_dev *indio_dev = st->indio_dev;
        int ret;
        /* Must ensure no interrupts can be generated after this!*/
        ret = sca3000_stop_all_interrupts(st);
        if (ret)
                return ret;
        if (spi->irq && gpio_is_valid(irq_to_gpio(spi->irq)) > 0)
                iio_unregister_interrupt_line(indio_dev, 0);
        iio_ring_buffer_unregister(indio_dev->ring);
        sca3000_unconfigure_ring(indio_dev);
        iio_device_unregister(indio_dev);

        kfree(st->tx);
        kfree(st->rx);
        kfree(st);

        return 0;
}

/* These macros save on an awful lot of repeated code */
#define SCA3000_VARIANT_PROBE(_name)                            \
        static int __devinit                                    \
        sca3000_##_name##_probe(struct spi_device *spi)         \
        {                                                       \
                return __sca3000_probe(spi, _name);             \
        }

#define SCA3000_VARIANT_SPI_DRIVER(_name)                       \
        struct spi_driver sca3000_##_name##_driver = {          \
                .driver = {                                     \
                        .name = "sca3000_" #_name,              \
                        .owner = THIS_MODULE,                   \
                },                                              \
                .probe = sca3000_##_name##_probe,               \
                .remove = __devexit_p(sca3000_remove),          \
        }

SCA3000_VARIANT_PROBE(d01);
static SCA3000_VARIANT_SPI_DRIVER(d01);

SCA3000_VARIANT_PROBE(d03);
static SCA3000_VARIANT_SPI_DRIVER(d03);

SCA3000_VARIANT_PROBE(e02);
static SCA3000_VARIANT_SPI_DRIVER(e02);

SCA3000_VARIANT_PROBE(e04);
static SCA3000_VARIANT_SPI_DRIVER(e04);

SCA3000_VARIANT_PROBE(e05);
static SCA3000_VARIANT_SPI_DRIVER(e05);

SCA3000_VARIANT_PROBE(l01);
static SCA3000_VARIANT_SPI_DRIVER(l01);

static __init int sca3000_init(void)
{
        int ret;

        ret = spi_register_driver(&sca3000_d01_driver);
        if (ret)
                goto error_ret;
        ret = spi_register_driver(&sca3000_d03_driver);
        if (ret)
                goto error_unreg_d01;
        ret = spi_register_driver(&sca3000_e02_driver);
        if (ret)
                goto error_unreg_d03;
        ret = spi_register_driver(&sca3000_e04_driver);
        if (ret)
                goto error_unreg_e02;
        ret = spi_register_driver(&sca3000_e05_driver);
        if (ret)
                goto error_unreg_e04;
        ret = spi_register_driver(&sca3000_l01_driver);
        if (ret)
                goto error_unreg_e05;

        return 0;

error_unreg_e05:
        spi_unregister_driver(&sca3000_e05_driver);
error_unreg_e04:
        spi_unregister_driver(&sca3000_e04_driver);
error_unreg_e02:
        spi_unregister_driver(&sca3000_e02_driver);
error_unreg_d03:
        spi_unregister_driver(&sca3000_d03_driver);
error_unreg_d01:
        spi_unregister_driver(&sca3000_d01_driver);
error_ret:

        return ret;
}

static __exit void sca3000_exit(void)
{
        spi_unregister_driver(&sca3000_l01_driver);
        spi_unregister_driver(&sca3000_e05_driver);
        spi_unregister_driver(&sca3000_e04_driver);
        spi_unregister_driver(&sca3000_e02_driver);
        spi_unregister_driver(&sca3000_d03_driver);
        spi_unregister_driver(&sca3000_d01_driver);
}

module_init(sca3000_init);
module_exit(sca3000_exit);

MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
MODULE_DESCRIPTION("VTI SCA3000 Series Accelerometers SPI driver");
MODULE_LICENSE("GPL v2");