linux-imx

/*

 * CM3232 Ambient Light Sensor

 *

 * Copyright (C) 2014-2015 Capella Microsystems Inc.

 * Author: Kevin Tsai <ktsai@capellamicro.com>

 *

 * 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.

 *

 * IIO driver for CM3232 (7-bit I2C slave address 0x10).

 */

​

#include <linux/i2c.h>

#include <linux/module.h>

#include <linux/iio/iio.h>

#include <linux/iio/sysfs.h>

#include <linux/init.h>

​

/* Registers Address */

#define CM3232_REG_ADDR_CMD     0x00

#define CM3232_REG_ADDR_ALS     0x50

#define CM3232_REG_ADDR_ID      0x53

​

#define CM3232_CMD_ALS_DISABLE      BIT(0)

​

#define CM3232_CMD_ALS_IT_SHIFT     2

#define CM3232_CMD_ALS_IT_MASK      (BIT(2) | BIT(3) | BIT(4))

#define CM3232_CMD_ALS_IT_DEFAULT   (0x01 << CM3232_CMD_ALS_IT_SHIFT)

​

#define CM3232_CMD_ALS_RESET        BIT(6)

​

#define CM3232_CMD_DEFAULT      CM3232_CMD_ALS_IT_DEFAULT

​

#define CM3232_HW_ID            0x32

#define CM3232_CALIBSCALE_DEFAULT   100000

#define CM3232_CALIBSCALE_RESOLUTION    100000

#define CM3232_MLUX_PER_LUX     1000

​

#define CM3232_MLUX_PER_BIT_DEFAULT 64

#define CM3232_MLUX_PER_BIT_BASE_IT 100000

​

static const struct {

    int val;

    int val2;

    u8 it;

} cm3232_als_it_scales[] = {

    {0, 100000, 0}, /* 0.100000 */

    {0, 200000, 1}, /* 0.200000 */

    {0, 400000, 2}, /* 0.400000 */

    {0, 800000, 3}, /* 0.800000 */

    {1, 600000, 4}, /* 1.600000 */

    {3, 200000, 5}, /* 3.200000 */

};

​

struct cm3232_als_info {

    u8 regs_cmd_default;

    u8 hw_id;

    int calibscale;

    int mlux_per_bit;

    int mlux_per_bit_base_it;

};

​

static struct cm3232_als_info cm3232_als_info_default = {

    .regs_cmd_default = CM3232_CMD_DEFAULT,

    .hw_id = CM3232_HW_ID,

    .calibscale = CM3232_CALIBSCALE_DEFAULT,

    .mlux_per_bit = CM3232_MLUX_PER_BIT_DEFAULT,

    .mlux_per_bit_base_it = CM3232_MLUX_PER_BIT_BASE_IT,

};

​

struct cm3232_chip {

    struct i2c_client *client;

    struct cm3232_als_info *als_info;

    u8 regs_cmd;

    u16 regs_als;

};

​

/**

 * cm3232_reg_init() - Initialize CM3232

 * @chip:   pointer of struct cm3232_chip.

 *

 * Check and initialize CM3232 ambient light sensor.

 *

 * Return: 0 for success; otherwise for error code.

 */

static int cm3232_reg_init(struct cm3232_chip *chip)

{

    struct i2c_client *client = chip->client;

    s32 ret;

​

    chip->als_info = &cm3232_als_info_default;