lis3lv02d.c

Go to the documentation of this file.

/*
 *  lis3lv02d.c - ST LIS3LV02DL accelerometer driver
 *
 *  Copyright (C) 2007-2008 Yan Burman
 *  Copyright (C) 2008 Eric Piel
 *  Copyright (C) 2008-2009 Pavel Machek
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/input-polldev.h>
#include <linux/delay.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/freezer.h>
#include <linux/uaccess.h>
#include <linux/miscdevice.h>
#include <linux/pm_runtime.h>
#include <linux/atomic.h>
#include <linux/of_device.h>
#include "lis3lv02d.h"

#define DRIVER_NAME     "lis3lv02d"

/* joystick device poll interval in milliseconds */
#define MDPS_POLL_INTERVAL 50
#define MDPS_POLL_MIN      0
#define MDPS_POLL_MAX      2000

#define LIS3_SYSFS_POWERDOWN_DELAY 5000 /* In milliseconds */

#define SELFTEST_OK        0
#define SELFTEST_FAIL          -1
#define SELFTEST_IRQ           -2

#define IRQ_LINE0          0
#define IRQ_LINE1          1

/*
 * The sensor can also generate interrupts (DRDY) but it's pretty pointless
 * because they are generated even if the data do not change. So it's better
 * to keep the interrupt for the free-fall event. The values are updated at
 * 40Hz (at the lowest frequency), but as it can be pretty time consuming on
 * some low processor, we poll the sensor only at 20Hz... enough for the
 * joystick.
 */

#define LIS3_PWRON_DELAY_WAI_12B    (5000)
#define LIS3_PWRON_DELAY_WAI_8B     (3000)

/*
 * LIS3LV02D spec says 1024 LSBs corresponds 1 G -> 1LSB is 1000/1024 mG
 * LIS302D spec says: 18 mG / digit
 * LIS3_ACCURACY is used to increase accuracy of the intermediate
 * calculation results.
 */
#define LIS3_ACCURACY           1024
/* Sensitivity values for -2G +2G scale */
#define LIS3_SENSITIVITY_12B        ((LIS3_ACCURACY * 1000) / 1024)
#define LIS3_SENSITIVITY_8B     (18 * LIS3_ACCURACY)

/*
 * LIS331DLH spec says 1LSBs corresponds 4G/4096 -> 1LSB is 1000/1024 mG.
 * Below macros defines sensitivity values for +/-2G. Dataout bits for
 * +/-2G range is 12 bits so 4 bits adjustment must be done to get 12bit
 * data from 16bit value. Currently this driver supports only 2G range.
 */
#define LIS3DLH_SENSITIVITY_2G      ((LIS3_ACCURACY * 1000) / 1024)
#define SHIFT_ADJ_2G            4

#define LIS3_DEFAULT_FUZZ_12B       3
#define LIS3_DEFAULT_FLAT_12B       3
#define LIS3_DEFAULT_FUZZ_8B        1
#define LIS3_DEFAULT_FLAT_8B        1

struct lis3lv02d lis3_dev = {
    .misc_wait   = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
};
EXPORT_SYMBOL_GPL(lis3_dev);

/* just like param_set_int() but does sanity-check so that it won't point
 * over the axis array size
 */
static int param_set_axis(const char *val, const struct kernel_param *kp)
{
    int ret = param_set_int(val, kp);
    if (!ret) {
        int val = *(int *)kp->arg;
        if (val < 0)
            val = -val;
        if (!val || val > 3)
            return -EINVAL;
    }
    return ret;
}

static struct kernel_param_ops param_ops_axis = {
    .set = param_set_axis,
    .get = param_get_int,
};

#define param_check_axis(name, p) param_check_int(name, p)

module_param_array_named(axes, lis3_dev.ac.as_array, axis, NULL, 0644);
MODULE_PARM_DESC(axes, "Axis-mapping for x,y,z directions");

static s16 lis3lv02d_read_8(struct lis3lv02d *lis3, int reg)
{
    s8 lo;
    if (lis3->read(lis3, reg, &lo) < 0)
        return 0;

    return lo;
}

static s16 lis3lv02d_read_12(struct lis3lv02d *lis3, int reg)
{
    u8 lo, hi;

    lis3->read(lis3, reg - 1, &lo);
    lis3->read(lis3, reg, &hi);
    /* In "12 bit right justified" mode, bit 6, bit 7, bit 8 = bit 5 */
    return (s16)((hi << 8) | lo);
}

/* 12bits for 2G range, 13 bits for 4G range and 14 bits for 8G range */
static s16 lis331dlh_read_data(struct lis3lv02d *lis3, int reg)
{
    u8 lo, hi;
    int v;

    lis3->read(lis3, reg - 1, &lo);
    lis3->read(lis3, reg, &hi);
    v = (int) ((hi << 8) | lo);

    return (s16) v >> lis3->shift_adj;
}

static inline int lis3lv02d_get_axis(s8 axis, int hw_values[3])
{
    if (axis > 0)
        return hw_values[axis - 1];
    else
        return -hw_values[-axis - 1];
}

static void lis3lv02d_get_xyz(struct lis3lv02d *lis3, int *x, int *y, int *z)
{
    int position[3];
    int i;

    if (lis3->blkread) {
        if (lis3->whoami == WAI_12B) {
            u16 data[3];
            lis3->blkread(lis3, OUTX_L, 6, (u8 *)data);
            for (i = 0; i < 3; i++)
                position[i] = (s16)le16_to_cpu(data[i]);
        } else {
            u8 data[5];
            /* Data: x, dummy, y, dummy, z */
            lis3->blkread(lis3, OUTX, 5, data);
            for (i = 0; i < 3; i++)
                position[i] = (s8)data[i * 2];
        }
    } else {
        position[0] = lis3->read_data(lis3, OUTX);
        position[1] = lis3->read_data(lis3, OUTY);
        position[2] = lis3->read_data(lis3, OUTZ);
    }

    for (i = 0; i < 3; i++)
        position[i] = (position[i] * lis3->scale) / LIS3_ACCURACY;

    *x = lis3lv02d_get_axis(lis3->ac.x, position);
    *y = lis3lv02d_get_axis(lis3->ac.y, position);
    *z = lis3lv02d_get_axis(lis3->ac.z, position);
}

/* conversion btw sampling rate and the register values */
static int lis3_12_rates[4] = {40, 160, 640, 2560};
static int lis3_8_rates[2] = {100, 400};
static int lis3_3dc_rates[16] = {0, 1, 10, 25, 50, 100, 200, 400, 1600, 5000};
static int lis3_3dlh_rates[4] = {50, 100, 400, 1000};

/* ODR is Output Data Rate */
static int lis3lv02d_get_odr(struct lis3lv02d *lis3)
{
    u8 ctrl;
    int shift;

    lis3->read(lis3, CTRL_REG1, &ctrl);
    ctrl &= lis3->odr_mask;
    shift = ffs(lis3->odr_mask) - 1;
    return lis3->odrs[(ctrl >> shift)];
}

static int lis3lv02d_get_pwron_wait(struct lis3lv02d *lis3)
{
    int div = lis3lv02d_get_odr(lis3);

    if (WARN_ONCE(div == 0, "device returned spurious data"))
        return -ENXIO;

    /* LIS3 power on delay is quite long */
    msleep(lis3->pwron_delay / div);
    return 0;
}

static int lis3lv02d_set_odr(struct lis3lv02d *lis3, int rate)
{
    u8 ctrl;
    int i, len, shift;

    if (!rate)
        return -EINVAL;

    lis3->read(lis3, CTRL_REG1, &ctrl);
    ctrl &= ~lis3->odr_mask;
    len = 1 << hweight_long(lis3->odr_mask); /* # of possible values */
    shift = ffs(lis3->odr_mask) - 1;

    for (i = 0; i < len; i++)
        if (lis3->odrs[i] == rate) {
            lis3->write(lis3, CTRL_REG1,
                    ctrl | (i << shift));
            return 0;
        }
    return -EINVAL;
}

static int lis3lv02d_selftest(struct lis3lv02d *lis3, s16 results[3])
{
    u8 ctlreg, reg;
    s16 x, y, z;
    u8 selftest;
    int ret;
    u8 ctrl_reg_data;
    unsigned char irq_cfg;

    mutex_lock(&lis3->mutex);

    irq_cfg = lis3->irq_cfg;
    if (lis3->whoami == WAI_8B) {
        lis3->data_ready_count[IRQ_LINE0] = 0;
        lis3->data_ready_count[IRQ_LINE1] = 0;

        /* Change interrupt cfg to data ready for selftest */
        atomic_inc(&lis3->wake_thread);
        lis3->irq_cfg = LIS3_IRQ1_DATA_READY | LIS3_IRQ2_DATA_READY;
        lis3->read(lis3, CTRL_REG3, &ctrl_reg_data);
        lis3->write(lis3, CTRL_REG3, (ctrl_reg_data &
                ~(LIS3_IRQ1_MASK | LIS3_IRQ2_MASK)) |
                (LIS3_IRQ1_DATA_READY | LIS3_IRQ2_DATA_READY));
    }

    if ((lis3->whoami == WAI_3DC) || (lis3->whoami == WAI_3DLH)) {
        ctlreg = CTRL_REG4;
        selftest = CTRL4_ST0;
    } else {
        ctlreg = CTRL_REG1;
        if (lis3->whoami == WAI_12B)
            selftest = CTRL1_ST;
        else
            selftest = CTRL1_STP;
    }

    lis3->read(lis3, ctlreg, &reg);
    lis3->write(lis3, ctlreg, (reg | selftest));
    ret = lis3lv02d_get_pwron_wait(lis3);
    if (ret)
        goto fail;

    /* Read directly to avoid axis remap */
    x = lis3->read_data(lis3, OUTX);
    y = lis3->read_data(lis3, OUTY);
    z = lis3->read_data(lis3, OUTZ);

    /* back to normal settings */
    lis3->write(lis3, ctlreg, reg);
    ret = lis3lv02d_get_pwron_wait(lis3);
    if (ret)
        goto fail;

    results[0] = x - lis3->read_data(lis3, OUTX);
    results[1] = y - lis3->read_data(lis3, OUTY);
    results[2] = z - lis3->read_data(lis3, OUTZ);

    ret = 0;

    if (lis3->whoami == WAI_8B) {
        /* Restore original interrupt configuration */
        atomic_dec(&lis3->wake_thread);
        lis3->write(lis3, CTRL_REG3, ctrl_reg_data);
        lis3->irq_cfg = irq_cfg;

        if ((irq_cfg & LIS3_IRQ1_MASK) &&
            lis3->data_ready_count[IRQ_LINE0] < 2) {
            ret = SELFTEST_IRQ;
            goto fail;
        }

        if ((irq_cfg & LIS3_IRQ2_MASK) &&
            lis3->data_ready_count[IRQ_LINE1] < 2) {
            ret = SELFTEST_IRQ;
            goto fail;
        }
    }

    if (lis3->pdata) {
        int i;
        for (i = 0; i < 3; i++) {
            /* Check against selftest acceptance limits */
            if ((results[i] < lis3->pdata->st_min_limits[i]) ||
                (results[i] > lis3->pdata->st_max_limits[i])) {
                ret = SELFTEST_FAIL;
                goto fail;
            }
        }
    }

    /* test passed */
fail:
    mutex_unlock(&lis3->mutex);
    return ret;
}

/*
 * Order of registers in the list affects to order of the restore process.
 * Perhaps it is a good idea to set interrupt enable register as a last one
 * after all other configurations
 */
static u8 lis3_wai8_regs[] = { FF_WU_CFG_1, FF_WU_THS_1, FF_WU_DURATION_1,
                   FF_WU_CFG_2, FF_WU_THS_2, FF_WU_DURATION_2,
                   CLICK_CFG, CLICK_SRC, CLICK_THSY_X, CLICK_THSZ,
                   CLICK_TIMELIMIT, CLICK_LATENCY, CLICK_WINDOW,
                   CTRL_REG1, CTRL_REG2, CTRL_REG3};

static u8 lis3_wai12_regs[] = {FF_WU_CFG, FF_WU_THS_L, FF_WU_THS_H,
                   FF_WU_DURATION, DD_CFG, DD_THSI_L, DD_THSI_H,
                   DD_THSE_L, DD_THSE_H,
                   CTRL_REG1, CTRL_REG3, CTRL_REG2};

static inline void lis3_context_save(struct lis3lv02d *lis3)
{
    int i;
    for (i = 0; i < lis3->regs_size; i++)
        lis3->read(lis3, lis3->regs[i], &lis3->reg_cache[i]);
    lis3->regs_stored = true;
}

static inline void lis3_context_restore(struct lis3lv02d *lis3)
{
    int i;
    if (lis3->regs_stored)
        for (i = 0; i < lis3->regs_size; i++)
            lis3->write(lis3, lis3->regs[i], lis3->reg_cache[i]);
}

void lis3lv02d_poweroff(struct lis3lv02d *lis3)
{
    if (lis3->reg_ctrl)
        lis3_context_save(lis3);
    /* disable X,Y,Z axis and power down */
    lis3->write(lis3, CTRL_REG1, 0x00);
    if (lis3->reg_ctrl)
        lis3->reg_ctrl(lis3, LIS3_REG_OFF);
}
EXPORT_SYMBOL_GPL(lis3lv02d_poweroff);

int lis3lv02d_poweron(struct lis3lv02d *lis3)
{
    int err;
    u8 reg;

    lis3->init(lis3);

    /*
     * Common configuration
     * BDU: (12 bits sensors only) LSB and MSB values are not updated until
     *      both have been read. So the value read will always be correct.
     * Set BOOT bit to refresh factory tuning values.
     */
    if (lis3->pdata) {
        lis3->read(lis3, CTRL_REG2, &reg);
        if (lis3->whoami ==  WAI_12B)
            reg |= CTRL2_BDU | CTRL2_BOOT;
        else if (lis3->whoami ==  WAI_3DLH)
            reg |= CTRL2_BOOT_3DLH;
        else
            reg |= CTRL2_BOOT_8B;
        lis3->write(lis3, CTRL_REG2, reg);

        if (lis3->whoami ==  WAI_3DLH) {
            lis3->read(lis3, CTRL_REG4, &reg);
            reg |= CTRL4_BDU;
            lis3->write(lis3, CTRL_REG4, reg);
        }
    }

    err = lis3lv02d_get_pwron_wait(lis3);
    if (err)
        return err;

    if (lis3->reg_ctrl)
        lis3_context_restore(lis3);

    return 0;
}
EXPORT_SYMBOL_GPL(lis3lv02d_poweron);


static void lis3lv02d_joystick_poll(struct input_polled_dev *pidev)
{
    struct lis3lv02d *lis3 = pidev->private;
    int x, y, z;

    mutex_lock(&lis3->mutex);
    lis3lv02d_get_xyz(lis3, &x, &y, &z);
    input_report_abs(pidev->input, ABS_X, x);
    input_report_abs(pidev->input, ABS_Y, y);
    input_report_abs(pidev->input, ABS_Z, z);
    input_sync(pidev->input);
    mutex_unlock(&lis3->mutex);
}

static void lis3lv02d_joystick_open(struct input_polled_dev *pidev)
{
    struct lis3lv02d *lis3 = pidev->private;

    if (lis3->pm_dev)
        pm_runtime_get_sync(lis3->pm_dev);

    if (lis3->pdata && lis3->whoami == WAI_8B && lis3->idev)
        atomic_set(&lis3->wake_thread, 1);
    /*
     * Update coordinates for the case where poll interval is 0 and
     * the chip in running purely under interrupt control
     */
    lis3lv02d_joystick_poll(pidev);
}

static void lis3lv02d_joystick_close(struct input_polled_dev *pidev)
{
    struct lis3lv02d *lis3 = pidev->private;

    atomic_set(&lis3->wake_thread, 0);
    if (lis3->pm_dev)
        pm_runtime_put(lis3->pm_dev);
}

static irqreturn_t lis302dl_interrupt(int irq, void *data)
{
    struct lis3lv02d *lis3 = data;

    if (!test_bit(0, &lis3->misc_opened))
        goto out;

    /*
     * Be careful: on some HP laptops the bios force DD when on battery and
     * the lid is closed. This leads to interrupts as soon as a little move
     * is done.
     */
    atomic_inc(&lis3->count);

    wake_up_interruptible(&lis3->misc_wait);
    kill_fasync(&lis3->async_queue, SIGIO, POLL_IN);
out:
    if (atomic_read(&lis3->wake_thread))
        return IRQ_WAKE_THREAD;
    return IRQ_HANDLED;
}

static void lis302dl_interrupt_handle_click(struct lis3lv02d *lis3)
{
    struct input_dev *dev = lis3->idev->input;
    u8 click_src;

    mutex_lock(&lis3->mutex);
    lis3->read(lis3, CLICK_SRC, &click_src);

    if (click_src & CLICK_SINGLE_X) {
        input_report_key(dev, lis3->mapped_btns[0], 1);
        input_report_key(dev, lis3->mapped_btns[0], 0);
    }

    if (click_src & CLICK_SINGLE_Y) {
        input_report_key(dev, lis3->mapped_btns[1], 1);
        input_report_key(dev, lis3->mapped_btns[1], 0);
    }

    if (click_src & CLICK_SINGLE_Z) {
        input_report_key(dev, lis3->mapped_btns[2], 1);
        input_report_key(dev, lis3->mapped_btns[2], 0);
    }
    input_sync(dev);
    mutex_unlock(&lis3->mutex);
}

static inline void lis302dl_data_ready(struct lis3lv02d *lis3, int index)
{
    int dummy;

    /* Dummy read to ack interrupt */
    lis3lv02d_get_xyz(lis3, &dummy, &dummy, &dummy);
    lis3->data_ready_count[index]++;
}

static irqreturn_t lis302dl_interrupt_thread1_8b(int irq, void *data)
{
    struct lis3lv02d *lis3 = data;
    u8 irq_cfg = lis3->irq_cfg & LIS3_IRQ1_MASK;

    if (irq_cfg == LIS3_IRQ1_CLICK)
        lis302dl_interrupt_handle_click(lis3);
    else if (unlikely(irq_cfg == LIS3_IRQ1_DATA_READY))
        lis302dl_data_ready(lis3, IRQ_LINE0);
    else
        lis3lv02d_joystick_poll(lis3->idev);

    return IRQ_HANDLED;
}

static irqreturn_t lis302dl_interrupt_thread2_8b(int irq, void *data)
{
    struct lis3lv02d *lis3 = data;
    u8 irq_cfg = lis3->irq_cfg & LIS3_IRQ2_MASK;

    if (irq_cfg == LIS3_IRQ2_CLICK)
        lis302dl_interrupt_handle_click(lis3);
    else if (unlikely(irq_cfg == LIS3_IRQ2_DATA_READY))
        lis302dl_data_ready(lis3, IRQ_LINE1);
    else
        lis3lv02d_joystick_poll(lis3->idev);

    return IRQ_HANDLED;
}

static int lis3lv02d_misc_open(struct inode *inode, struct file *file)
{
    struct lis3lv02d *lis3 = container_of(file->private_data,
                          struct lis3lv02d, miscdev);

    if (test_and_set_bit(0, &lis3->misc_opened))
        return -EBUSY; /* already open */

    if (lis3->pm_dev)
        pm_runtime_get_sync(lis3->pm_dev);

    atomic_set(&lis3->count, 0);
    return 0;
}

static int lis3lv02d_misc_release(struct inode *inode, struct file *file)
{
    struct lis3lv02d *lis3 = container_of(file->private_data,
                          struct lis3lv02d, miscdev);

    fasync_helper(-1, file, 0, &lis3->async_queue);
    clear_bit(0, &lis3->misc_opened); /* release the device */
    if (lis3->pm_dev)
        pm_runtime_put(lis3->pm_dev);
    return 0;
}

static ssize_t lis3lv02d_misc_read(struct file *file, char __user *buf,
                size_t count, loff_t *pos)
{
    struct lis3lv02d *lis3 = container_of(file->private_data,
                          struct lis3lv02d, miscdev);

    DECLARE_WAITQUEUE(wait, current);
    u32 data;
    unsigned char byte_data;
    ssize_t retval = 1;

    if (count < 1)
        return -EINVAL;

    add_wait_queue(&lis3->misc_wait, &wait);
    while (true) {
        set_current_state(TASK_INTERRUPTIBLE);
        data = atomic_xchg(&lis3->count, 0);
        if (data)
            break;

        if (file->f_flags & O_NONBLOCK) {
            retval = -EAGAIN;
            goto out;
        }

        if (signal_pending(current)) {
            retval = -ERESTARTSYS;
            goto out;
        }

        schedule();
    }

    if (data < 255)
        byte_data = data;
    else
        byte_data = 255;

    /* make sure we are not going into copy_to_user() with
     * TASK_INTERRUPTIBLE state */
    set_current_state(TASK_RUNNING);
    if (copy_to_user(buf, &byte_data, sizeof(byte_data)))
        retval = -EFAULT;

out:
    __set_current_state(TASK_RUNNING);
    remove_wait_queue(&lis3->misc_wait, &wait);

    return retval;
}

static unsigned int lis3lv02d_misc_poll(struct file *file, poll_table *wait)
{
    struct lis3lv02d *lis3 = container_of(file->private_data,
                          struct lis3lv02d, miscdev);

    poll_wait(file, &lis3->misc_wait, wait);
    if (atomic_read(&lis3->count))
        return POLLIN | POLLRDNORM;
    return 0;
}

static int lis3lv02d_misc_fasync(int fd, struct file *file, int on)
{
    struct lis3lv02d *lis3 = container_of(file->private_data,
                          struct lis3lv02d, miscdev);

    return fasync_helper(fd, file, on, &lis3->async_queue);
}

static const struct file_operations lis3lv02d_misc_fops = {
    .owner   = THIS_MODULE,
    .llseek  = no_llseek,
    .read    = lis3lv02d_misc_read,
    .open    = lis3lv02d_misc_open,
    .release = lis3lv02d_misc_release,
    .poll    = lis3lv02d_misc_poll,
    .fasync  = lis3lv02d_misc_fasync,
};

int lis3lv02d_joystick_enable(struct lis3lv02d *lis3)
{
    struct input_dev *input_dev;
    int err;
    int max_val, fuzz, flat;
    int btns[] = {BTN_X, BTN_Y, BTN_Z};

    if (lis3->idev)
        return -EINVAL;

    lis3->idev = input_allocate_polled_device();
    if (!lis3->idev)
        return -ENOMEM;

    lis3->idev->poll = lis3lv02d_joystick_poll;
    lis3->idev->open = lis3lv02d_joystick_open;
    lis3->idev->close = lis3lv02d_joystick_close;
    lis3->idev->poll_interval = MDPS_POLL_INTERVAL;
    lis3->idev->poll_interval_min = MDPS_POLL_MIN;
    lis3->idev->poll_interval_max = MDPS_POLL_MAX;
    lis3->idev->private = lis3;
    input_dev = lis3->idev->input;

    input_dev->name       = "ST LIS3LV02DL Accelerometer";
    input_dev->phys       = DRIVER_NAME "/input0";
    input_dev->id.bustype = BUS_HOST;
    input_dev->id.vendor  = 0;
    input_dev->dev.parent = &lis3->pdev->dev;

    set_bit(EV_ABS, input_dev->evbit);
    max_val = (lis3->mdps_max_val * lis3->scale) / LIS3_ACCURACY;
    if (lis3->whoami == WAI_12B) {
        fuzz = LIS3_DEFAULT_FUZZ_12B;
        flat = LIS3_DEFAULT_FLAT_12B;
    } else {
        fuzz = LIS3_DEFAULT_FUZZ_8B;
        flat = LIS3_DEFAULT_FLAT_8B;
    }
    fuzz = (fuzz * lis3->scale) / LIS3_ACCURACY;
    flat = (flat * lis3->scale) / LIS3_ACCURACY;

    input_set_abs_params(input_dev, ABS_X, -max_val, max_val, fuzz, flat);
    input_set_abs_params(input_dev, ABS_Y, -max_val, max_val, fuzz, flat);
    input_set_abs_params(input_dev, ABS_Z, -max_val, max_val, fuzz, flat);

    lis3->mapped_btns[0] = lis3lv02d_get_axis(abs(lis3->ac.x), btns);
    lis3->mapped_btns[1] = lis3lv02d_get_axis(abs(lis3->ac.y), btns);
    lis3->mapped_btns[2] = lis3lv02d_get_axis(abs(lis3->ac.z), btns);

    err = input_register_polled_device(lis3->idev);
    if (err) {
        input_free_polled_device(lis3->idev);
        lis3->idev = NULL;
    }

    return err;
}
EXPORT_SYMBOL_GPL(lis3lv02d_joystick_enable);

void lis3lv02d_joystick_disable(struct lis3lv02d *lis3)
{
    if (lis3->irq)
        free_irq(lis3->irq, lis3);
    if (lis3->pdata && lis3->pdata->irq2)
        free_irq(lis3->pdata->irq2, lis3);

    if (!lis3->idev)
        return;

    if (lis3->irq)
        misc_deregister(&lis3->miscdev);
    input_unregister_polled_device(lis3->idev);
    input_free_polled_device(lis3->idev);
    lis3->idev = NULL;
}
EXPORT_SYMBOL_GPL(lis3lv02d_joystick_disable);

/* Sysfs stuff */
static void lis3lv02d_sysfs_poweron(struct lis3lv02d *lis3)
{
    /*
     * SYSFS functions are fast visitors so put-call
     * immediately after the get-call. However, keep
     * chip running for a while and schedule delayed
     * suspend. This way periodic sysfs calls doesn't
     * suffer from relatively long power up time.
     */

    if (lis3->pm_dev) {
        pm_runtime_get_sync(lis3->pm_dev);
        pm_runtime_put_noidle(lis3->pm_dev);
        pm_schedule_suspend(lis3->pm_dev, LIS3_SYSFS_POWERDOWN_DELAY);
    }
}

static ssize_t lis3lv02d_selftest_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct lis3lv02d *lis3 = dev_get_drvdata(dev);
    s16 values[3];

    static const char ok[] = "OK";
    static const char fail[] = "FAIL";
    static const char irq[] = "FAIL_IRQ";
    const char *res;

    lis3lv02d_sysfs_poweron(lis3);
    switch (lis3lv02d_selftest(lis3, values)) {
    case SELFTEST_FAIL:
        res = fail;
        break;
    case SELFTEST_IRQ:
        res = irq;
        break;
    case SELFTEST_OK:
    default:
        res = ok;
        break;
    }
    return sprintf(buf, "%s %d %d %d\n", res,
        values[0], values[1], values[2]);
}

static ssize_t lis3lv02d_position_show(struct device *dev,
                struct device_attribute *attr, char *buf)
{
    struct lis3lv02d *lis3 = dev_get_drvdata(dev);
    int x, y, z;

    lis3lv02d_sysfs_poweron(lis3);
    mutex_lock(&lis3->mutex);
    lis3lv02d_get_xyz(lis3, &x, &y, &z);
    mutex_unlock(&lis3->mutex);
    return sprintf(buf, "(%d,%d,%d)\n", x, y, z);
}

static ssize_t lis3lv02d_rate_show(struct device *dev,
            struct device_attribute *attr, char *buf)
{
    struct lis3lv02d *lis3 = dev_get_drvdata(dev);

    lis3lv02d_sysfs_poweron(lis3);
    return sprintf(buf, "%d\n", lis3lv02d_get_odr(lis3));
}

static ssize_t lis3lv02d_rate_set(struct device *dev,
                struct device_attribute *attr, const char *buf,
                size_t count)
{
    struct lis3lv02d *lis3 = dev_get_drvdata(dev);
    unsigned long rate;

    if (strict_strtoul(buf, 0, &rate))
        return -EINVAL;

    lis3lv02d_sysfs_poweron(lis3);
    if (lis3lv02d_set_odr(lis3, rate))
        return -EINVAL;

    return count;
}

static DEVICE_ATTR(selftest, S_IRUSR, lis3lv02d_selftest_show, NULL);
static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL);
static DEVICE_ATTR(rate, S_IRUGO | S_IWUSR, lis3lv02d_rate_show,
                        lis3lv02d_rate_set);

static struct attribute *lis3lv02d_attributes[] = {
    &dev_attr_selftest.attr,
    &dev_attr_position.attr,
    &dev_attr_rate.attr,
    NULL
};

static struct attribute_group lis3lv02d_attribute_group = {
    .attrs = lis3lv02d_attributes
};


static int lis3lv02d_add_fs(struct lis3lv02d *lis3)
{
    lis3->pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
    if (IS_ERR(lis3->pdev))
        return PTR_ERR(lis3->pdev);

    platform_set_drvdata(lis3->pdev, lis3);
    return sysfs_create_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
}

int lis3lv02d_remove_fs(struct lis3lv02d *lis3)
{
    sysfs_remove_group(&lis3->pdev->dev.kobj, &lis3lv02d_attribute_group);
    platform_device_unregister(lis3->pdev);
    if (lis3->pm_dev) {
        /* Barrier after the sysfs remove */
        pm_runtime_barrier(lis3->pm_dev);

        /* SYSFS may have left chip running. Turn off if necessary */
        if (!pm_runtime_suspended(lis3->pm_dev))
            lis3lv02d_poweroff(lis3);

        pm_runtime_disable(lis3->pm_dev);
        pm_runtime_set_suspended(lis3->pm_dev);
    }
    kfree(lis3->reg_cache);
    return 0;
}
EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs);

static void lis3lv02d_8b_configure(struct lis3lv02d *lis3,
                struct lis3lv02d_platform_data *p)
{
    int err;
    int ctrl2 = p->hipass_ctrl;

    if (p->click_flags) {
        lis3->write(lis3, CLICK_CFG, p->click_flags);
        lis3->write(lis3, CLICK_TIMELIMIT, p->click_time_limit);
        lis3->write(lis3, CLICK_LATENCY, p->click_latency);
        lis3->write(lis3, CLICK_WINDOW, p->click_window);
        lis3->write(lis3, CLICK_THSZ, p->click_thresh_z & 0xf);
        lis3->write(lis3, CLICK_THSY_X,
            (p->click_thresh_x & 0xf) |
            (p->click_thresh_y << 4));

        if (lis3->idev) {
            struct input_dev *input_dev = lis3->idev->input;
            input_set_capability(input_dev, EV_KEY, BTN_X);
            input_set_capability(input_dev, EV_KEY, BTN_Y);
            input_set_capability(input_dev, EV_KEY, BTN_Z);
        }
    }

    if (p->wakeup_flags) {
        lis3->write(lis3, FF_WU_CFG_1, p->wakeup_flags);
        lis3->write(lis3, FF_WU_THS_1, p->wakeup_thresh & 0x7f);
        /* pdata value + 1 to keep this backward compatible*/
        lis3->write(lis3, FF_WU_DURATION_1, p->duration1 + 1);
        ctrl2 ^= HP_FF_WU1; /* Xor to keep compatible with old pdata*/
    }

    if (p->wakeup_flags2) {
        lis3->write(lis3, FF_WU_CFG_2, p->wakeup_flags2);
        lis3->write(lis3, FF_WU_THS_2, p->wakeup_thresh2 & 0x7f);
        /* pdata value + 1 to keep this backward compatible*/
        lis3->write(lis3, FF_WU_DURATION_2, p->duration2 + 1);
        ctrl2 ^= HP_FF_WU2; /* Xor to keep compatible with old pdata*/
    }
    /* Configure hipass filters */
    lis3->write(lis3, CTRL_REG2, ctrl2);

    if (p->irq2) {
        err = request_threaded_irq(p->irq2,
                    NULL,
                    lis302dl_interrupt_thread2_8b,
                    IRQF_TRIGGER_RISING | IRQF_ONESHOT |
                    (p->irq_flags2 & IRQF_TRIGGER_MASK),
                    DRIVER_NAME, lis3);
        if (err < 0)
            pr_err("No second IRQ. Limited functionality\n");
    }
}

#ifdef CONFIG_OF
int lis3lv02d_init_dt(struct lis3lv02d *lis3)
{
    struct lis3lv02d_platform_data *pdata;
    struct device_node *np = lis3->of_node;
    u32 val;

    if (!lis3->of_node)
        return 0;

    pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
    if (!pdata)
        return -ENOMEM;

    if (of_get_property(np, "st,click-single-x", NULL))
        pdata->click_flags |= LIS3_CLICK_SINGLE_X;
    if (of_get_property(np, "st,click-double-x", NULL))
        pdata->click_flags |= LIS3_CLICK_DOUBLE_X;

    if (of_get_property(np, "st,click-single-y", NULL))
        pdata->click_flags |= LIS3_CLICK_SINGLE_Y;
    if (of_get_property(np, "st,click-double-y", NULL))
        pdata->click_flags |= LIS3_CLICK_DOUBLE_Y;

    if (of_get_property(np, "st,click-single-z", NULL))
        pdata->click_flags |= LIS3_CLICK_SINGLE_Z;
    if (of_get_property(np, "st,click-double-z", NULL))
        pdata->click_flags |= LIS3_CLICK_DOUBLE_Z;

    if (!of_property_read_u32(np, "st,click-threshold-x", &val))
        pdata->click_thresh_x = val;
    if (!of_property_read_u32(np, "st,click-threshold-y", &val))
        pdata->click_thresh_y = val;
    if (!of_property_read_u32(np, "st,click-threshold-z", &val))
        pdata->click_thresh_z = val;

    if (!of_property_read_u32(np, "st,click-time-limit", &val))
        pdata->click_time_limit = val;
    if (!of_property_read_u32(np, "st,click-latency", &val))
        pdata->click_latency = val;
    if (!of_property_read_u32(np, "st,click-window", &val))
        pdata->click_window = val;

    if (of_get_property(np, "st,irq1-disable", NULL))
        pdata->irq_cfg |= LIS3_IRQ1_DISABLE;
    if (of_get_property(np, "st,irq1-ff-wu-1", NULL))
        pdata->irq_cfg |= LIS3_IRQ1_FF_WU_1;
    if (of_get_property(np, "st,irq1-ff-wu-2", NULL))
        pdata->irq_cfg |= LIS3_IRQ1_FF_WU_2;
    if (of_get_property(np, "st,irq1-data-ready", NULL))
        pdata->irq_cfg |= LIS3_IRQ1_DATA_READY;
    if (of_get_property(np, "st,irq1-click", NULL))
        pdata->irq_cfg |= LIS3_IRQ1_CLICK;

    if (of_get_property(np, "st,irq2-disable", NULL))
        pdata->irq_cfg |= LIS3_IRQ2_DISABLE;
    if (of_get_property(np, "st,irq2-ff-wu-1", NULL))
        pdata->irq_cfg |= LIS3_IRQ2_FF_WU_1;
    if (of_get_property(np, "st,irq2-ff-wu-2", NULL))
        pdata->irq_cfg |= LIS3_IRQ2_FF_WU_2;
    if (of_get_property(np, "st,irq2-data-ready", NULL))
        pdata->irq_cfg |= LIS3_IRQ2_DATA_READY;
    if (of_get_property(np, "st,irq2-click", NULL))
        pdata->irq_cfg |= LIS3_IRQ2_CLICK;

    if (of_get_property(np, "st,irq-open-drain", NULL))
        pdata->irq_cfg |= LIS3_IRQ_OPEN_DRAIN;
    if (of_get_property(np, "st,irq-active-low", NULL))
        pdata->irq_cfg |= LIS3_IRQ_ACTIVE_LOW;

    if (!of_property_read_u32(np, "st,wu-duration-1", &val))
        pdata->duration1 = val;
    if (!of_property_read_u32(np, "st,wu-duration-2", &val))
        pdata->duration2 = val;

    if (of_get_property(np, "st,wakeup-x-lo", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_X_LO;
    if (of_get_property(np, "st,wakeup-x-hi", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_X_HI;
    if (of_get_property(np, "st,wakeup-y-lo", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_Y_LO;
    if (of_get_property(np, "st,wakeup-y-hi", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_Y_HI;
    if (of_get_property(np, "st,wakeup-z-lo", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_Z_LO;
    if (of_get_property(np, "st,wakeup-z-hi", NULL))
        pdata->wakeup_flags |= LIS3_WAKEUP_Z_HI;

    if (!of_property_read_u32(np, "st,highpass-cutoff-hz", &val)) {
        switch (val) {
        case 1:
            pdata->hipass_ctrl = LIS3_HIPASS_CUTFF_1HZ;
            break;
        case 2:
            pdata->hipass_ctrl = LIS3_HIPASS_CUTFF_2HZ;
            break;
        case 4:
            pdata->hipass_ctrl = LIS3_HIPASS_CUTFF_4HZ;
            break;
        case 8:
            pdata->hipass_ctrl = LIS3_HIPASS_CUTFF_8HZ;
            break;
        }
    }

    if (of_get_property(np, "st,hipass1-disable", NULL))
        pdata->hipass_ctrl |= LIS3_HIPASS1_DISABLE;
    if (of_get_property(np, "st,hipass2-disable", NULL))
        pdata->hipass_ctrl |= LIS3_HIPASS2_DISABLE;

    if (of_get_property(np, "st,axis-x", &val))
        pdata->axis_x = val;
    if (of_get_property(np, "st,axis-y", &val))
        pdata->axis_y = val;
    if (of_get_property(np, "st,axis-z", &val))
        pdata->axis_z = val;

    if (of_get_property(np, "st,default-rate", NULL))
        pdata->default_rate = val;

    if (of_get_property(np, "st,min-limit-x", &val))
        pdata->st_min_limits[0] = val;
    if (of_get_property(np, "st,min-limit-y", &val))
        pdata->st_min_limits[1] = val;
    if (of_get_property(np, "st,min-limit-z", &val))
        pdata->st_min_limits[2] = val;

    if (of_get_property(np, "st,max-limit-x", &val))
        pdata->st_max_limits[0] = val;
    if (of_get_property(np, "st,max-limit-y", &val))
        pdata->st_max_limits[1] = val;
    if (of_get_property(np, "st,max-limit-z", &val))
        pdata->st_max_limits[2] = val;


    lis3->pdata = pdata;

    return 0;
}

#else
int lis3lv02d_init_dt(struct lis3lv02d *lis3)
{
    return 0;
}
#endif
EXPORT_SYMBOL_GPL(lis3lv02d_init_dt);

/*
 * Initialise the accelerometer and the various subsystems.
 * Should be rather independent of the bus system.
 */
int lis3lv02d_init_device(struct lis3lv02d *lis3)
{
    int err;
    irq_handler_t thread_fn;
    int irq_flags = 0;

    lis3->whoami = lis3lv02d_read_8(lis3, WHO_AM_I);

    switch (lis3->whoami) {
    case WAI_12B:
        pr_info("12 bits sensor found\n");
        lis3->read_data = lis3lv02d_read_12;
        lis3->mdps_max_val = 2048;
        lis3->pwron_delay = LIS3_PWRON_DELAY_WAI_12B;
        lis3->odrs = lis3_12_rates;
        lis3->odr_mask = CTRL1_DF0 | CTRL1_DF1;
        lis3->scale = LIS3_SENSITIVITY_12B;
        lis3->regs = lis3_wai12_regs;
        lis3->regs_size = ARRAY_SIZE(lis3_wai12_regs);
        break;
    case WAI_8B:
        pr_info("8 bits sensor found\n");
        lis3->read_data = lis3lv02d_read_8;
        lis3->mdps_max_val = 128;
        lis3->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
        lis3->odrs = lis3_8_rates;
        lis3->odr_mask = CTRL1_DR;
        lis3->scale = LIS3_SENSITIVITY_8B;
        lis3->regs = lis3_wai8_regs;
        lis3->regs_size = ARRAY_SIZE(lis3_wai8_regs);
        break;
    case WAI_3DC:
        pr_info("8 bits 3DC sensor found\n");
        lis3->read_data = lis3lv02d_read_8;
        lis3->mdps_max_val = 128;
        lis3->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
        lis3->odrs = lis3_3dc_rates;
        lis3->odr_mask = CTRL1_ODR0|CTRL1_ODR1|CTRL1_ODR2|CTRL1_ODR3;
        lis3->scale = LIS3_SENSITIVITY_8B;
        break;
    case WAI_3DLH:
        pr_info("16 bits lis331dlh sensor found\n");
        lis3->read_data = lis331dlh_read_data;
        lis3->mdps_max_val = 2048; /* 12 bits for 2G */
        lis3->shift_adj = SHIFT_ADJ_2G;
        lis3->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
        lis3->odrs = lis3_3dlh_rates;
        lis3->odr_mask = CTRL1_DR0 | CTRL1_DR1;
        lis3->scale = LIS3DLH_SENSITIVITY_2G;
        break;
    default:
        pr_err("unknown sensor type 0x%X\n", lis3->whoami);
        return -EINVAL;
    }

    lis3->reg_cache = kzalloc(max(sizeof(lis3_wai8_regs),
                     sizeof(lis3_wai12_regs)), GFP_KERNEL);

    if (lis3->reg_cache == NULL) {
        printk(KERN_ERR DRIVER_NAME "out of memory\n");
        return -ENOMEM;
    }

    mutex_init(&lis3->mutex);
    atomic_set(&lis3->wake_thread, 0);

    lis3lv02d_add_fs(lis3);
    err = lis3lv02d_poweron(lis3);
    if (err) {
        lis3lv02d_remove_fs(lis3);
        return err;
    }

    if (lis3->pm_dev) {
        pm_runtime_set_active(lis3->pm_dev);
        pm_runtime_enable(lis3->pm_dev);
    }

    if (lis3lv02d_joystick_enable(lis3))
        pr_err("joystick initialization failed\n");

    /* passing in platform specific data is purely optional and only
     * used by the SPI transport layer at the moment */
    if (lis3->pdata) {
        struct lis3lv02d_platform_data *p = lis3->pdata;

        if (lis3->whoami == WAI_8B)
            lis3lv02d_8b_configure(lis3, p);

        irq_flags = p->irq_flags1 & IRQF_TRIGGER_MASK;

        lis3->irq_cfg = p->irq_cfg;
        if (p->irq_cfg)
            lis3->write(lis3, CTRL_REG3, p->irq_cfg);

        if (p->default_rate)
            lis3lv02d_set_odr(lis3, p->default_rate);
    }

    /* bail if we did not get an IRQ from the bus layer */
    if (!lis3->irq) {
        pr_debug("No IRQ. Disabling /dev/freefall\n");
        goto out;
    }

    /*
     * The sensor can generate interrupts for free-fall and direction
     * detection (distinguishable with FF_WU_SRC and DD_SRC) but to keep
     * the things simple and _fast_ we activate it only for free-fall, so
     * no need to read register (very slow with ACPI). For the same reason,
     * we forbid shared interrupts.
     *
     * IRQF_TRIGGER_RISING seems pointless on HP laptops because the
     * io-apic is not configurable (and generates a warning) but I keep it
     * in case of support for other hardware.
     */
    if (lis3->pdata && lis3->whoami == WAI_8B)
        thread_fn = lis302dl_interrupt_thread1_8b;
    else
        thread_fn = NULL;

    err = request_threaded_irq(lis3->irq, lis302dl_interrupt,
                thread_fn,
                IRQF_TRIGGER_RISING | IRQF_ONESHOT |
                irq_flags,
                DRIVER_NAME, lis3);

    if (err < 0) {
        pr_err("Cannot get IRQ\n");
        goto out;
    }

    lis3->miscdev.minor = MISC_DYNAMIC_MINOR;
    lis3->miscdev.name  = "freefall";
    lis3->miscdev.fops  = &lis3lv02d_misc_fops;

    if (misc_register(&lis3->miscdev))
        pr_err("misc_register failed\n");
out:
    return 0;
}
EXPORT_SYMBOL_GPL(lis3lv02d_init_device);

MODULE_DESCRIPTION("ST LIS3LV02Dx three-axis digital accelerometer driver");
MODULE_AUTHOR("Yan Burman, Eric Piel, Pavel Machek");
MODULE_LICENSE("GPL");