linux-imx

/*

 *  Driver for Freescale's 3-Axis Accelerometer MMA8450

 *

 *  Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.

 *

 *  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., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

​

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/delay.h>

#include <linux/i2c.h>

#include <linux/input-polldev.h>

#include <linux/of_device.h>

​

#define MMA8450_DRV_NAME    "mma8450"

​

#define MODE_CHANGE_DELAY_MS    100

#define POLL_INTERVAL       100

#define POLL_INTERVAL_MAX   500

​

/* register definitions */

#define MMA8450_STATUS      0x00

#define MMA8450_STATUS_ZXYDR    0x08

​

#define MMA8450_OUT_X8      0x01

#define MMA8450_OUT_Y8      0x02

#define MMA8450_OUT_Z8      0x03

​

#define MMA8450_OUT_X_LSB   0x05

#define MMA8450_OUT_X_MSB   0x06

#define MMA8450_OUT_Y_LSB   0x07

#define MMA8450_OUT_Y_MSB   0x08

#define MMA8450_OUT_Z_LSB   0x09

#define MMA8450_OUT_Z_MSB   0x0a

​

#define MMA8450_XYZ_DATA_CFG    0x16

​

#define MMA8450_CTRL_REG1   0x38

#define MMA8450_CTRL_REG2   0x39

​

/* mma8450 status */

struct mma8450 {

    struct i2c_client   *client;

    struct input_polled_dev *idev;

};

​

static int mma8450_read(struct mma8450 *m, unsigned off)

{

    struct i2c_client *c = m->client;