linux-imx

/*

 * ltr501.c - Support for Lite-On LTR501 ambient light and proximity sensor

 *

 * Copyright 2014 Peter Meerwald <pmeerw@pmeerw.net>

 *

 * This file is subject to the terms and conditions of version 2 of

 * the GNU General Public License.  See the file COPYING in the main

 * directory of this archive for more details.

 *

 * 7-bit I2C slave address 0x23

 *

 * TODO: IR LED characteristics

 */

​

#include <linux/module.h>

#include <linux/i2c.h>

#include <linux/err.h>

#include <linux/delay.h>

#include <linux/regmap.h>

#include <linux/acpi.h>

​

#include <linux/iio/iio.h>

#include <linux/iio/events.h>

#include <linux/iio/sysfs.h>

#include <linux/iio/trigger_consumer.h>

#include <linux/iio/buffer.h>

#include <linux/iio/triggered_buffer.h>

​

#define LTR501_DRV_NAME "ltr501"

​

#define LTR501_ALS_CONTR 0x80 /* ALS operation mode, SW reset */

#define LTR501_PS_CONTR 0x81 /* PS operation mode */

#define LTR501_PS_MEAS_RATE 0x84 /* measurement rate*/

#define LTR501_ALS_MEAS_RATE 0x85 /* ALS integ time, measurement rate*/

#define LTR501_PART_ID 0x86

#define LTR501_MANUFAC_ID 0x87

#define LTR501_ALS_DATA1 0x88 /* 16-bit, little endian */

#define LTR501_ALS_DATA0 0x8a /* 16-bit, little endian */

#define LTR501_ALS_PS_STATUS 0x8c

#define LTR501_PS_DATA 0x8d /* 16-bit, little endian */

#define LTR501_INTR 0x8f /* output mode, polarity, mode */

#define LTR501_PS_THRESH_UP 0x90 /* 11 bit, ps upper threshold */

#define LTR501_PS_THRESH_LOW 0x92 /* 11 bit, ps lower threshold */

#define LTR501_ALS_THRESH_UP 0x97 /* 16 bit, ALS upper threshold */

#define LTR501_ALS_THRESH_LOW 0x99 /* 16 bit, ALS lower threshold */

#define LTR501_INTR_PRST 0x9e /* ps thresh, als thresh */

#define LTR501_MAX_REG 0x9f

​

#define LTR501_ALS_CONTR_SW_RESET BIT(2)

#define LTR501_CONTR_PS_GAIN_MASK (BIT(3) | BIT(2))

#define LTR501_CONTR_PS_GAIN_SHIFT 2

#define LTR501_CONTR_ALS_GAIN_MASK BIT(3)

#define LTR501_CONTR_ACTIVE BIT(1)

​

#define LTR501_STATUS_ALS_INTR BIT(3)

#define LTR501_STATUS_ALS_RDY BIT(2)

#define LTR501_STATUS_PS_INTR BIT(1)

#define LTR501_STATUS_PS_RDY BIT(0)

​

#define LTR501_PS_DATA_MASK 0x7ff

#define LTR501_PS_THRESH_MASK 0x7ff

#define LTR501_ALS_THRESH_MASK 0xffff

​

#define LTR501_ALS_DEF_PERIOD 500000

#define LTR501_PS_DEF_PERIOD 100000

​

#define LTR501_REGMAP_NAME "ltr501_regmap"

​

#define LTR501_LUX_CONV(vis_coeff, vis_data, ir_coeff, ir_data) \

            ((vis_coeff * vis_data) - (ir_coeff * ir_data))

​

static const int int_time_mapping[] = {100000, 50000, 200000, 400000};

​

static const struct reg_field reg_field_it =

                REG_FIELD(LTR501_ALS_MEAS_RATE, 3, 4);

static const struct reg_field reg_field_als_intr =

                REG_FIELD(LTR501_INTR, 1, 1);

static const struct reg_field reg_field_ps_intr =

                REG_FIELD(LTR501_INTR, 0, 0);

static const struct reg_field reg_field_als_rate =

                REG_FIELD(LTR501_ALS_MEAS_RATE, 0, 2);

static const struct reg_field reg_field_ps_rate =

                REG_FIELD(LTR501_PS_MEAS_RATE, 0, 3);

static const struct reg_field reg_field_als_prst =

                REG_FIELD(LTR501_INTR_PRST, 0, 3);

static const struct reg_field reg_field_ps_prst =

                REG_FIELD(LTR501_INTR_PRST, 4, 7);

​

struct ltr501_samp_table {

    int freq_val;  /* repetition frequency in micro HZ*/

    int time_val; /* repetition rate in micro seconds */

};