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/*
* Copyright 2015 Ludwig Knüpfer
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup driver_isl29125
* @{
*
* @file
* @brief Device driver implementation for the ISL29125 RGB light sensor
*
* @author Ludwig Knüpfer <ludwig.knuepfer@fu-berlin.de>
*
* @}
*/
#include <stdint.h>
#include "isl29125.h"
#include "isl29125-internal.h"
#include "periph/i2c.h"
#include "periph/gpio.h"
#include "color.h"
#define ENABLE_DEBUG (0)
#include "debug.h"
/***********************************************************************
* public API implementation
**********************************************************************/
int isl29125_init(isl29125_t *dev, i2c_t i2c, gpio_t gpio,
isl29125_mode_t mode, isl29125_range_t range,
isl29125_resolution_t resolution)
{
DEBUG("isl29125_init\n");
/* initialize device descriptor */
dev->i2c = i2c;
dev->res = resolution;
dev->range = range;
dev->gpio = gpio;
/* configuration 1: operation mode, range, resolution */
char conf1 = 0x00;
conf1 |= mode;
conf1 |= range;
conf1 |= resolution;
conf1 |= ISL29125_CON1_SYNCOFF; /* TODO: implement SYNC mode configuration */
/* TODO: implement configuration 2: infrared compensation configuration */
/* TODO: implement configuration 3: interrupt mode configuration */
/* acquire exclusive access to the bus */
DEBUG("isl29125_init: i2c_acquire\n");
(void) i2c_acquire(dev->i2c);
/* initialize the I2C bus */
DEBUG("isl29125_init: i2c_init_master\n");
(void) i2c_init_master(i2c, I2C_SPEED_NORMAL);
/* verify the device ID */
DEBUG("isl29125_init: i2c_read_reg\n");
char reg_id;
int ret = i2c_read_reg(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_ID, &reg_id);
if ((reg_id == ISL29125_ID) && (ret == 1)) {
DEBUG("isl29125_init: ID successfully verified\n");
}
else {
DEBUG("isl29125_init: ID could not be verified, ret: %i\n", ret);
(void) i2c_release(dev->i2c);
return -1;
}
/* configure and enable the sensor */
DEBUG("isl29125_init: i2c_write_reg(ISL29125_REG_RESET)\n");
(void) i2c_write_reg(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_RESET, ISL29125_CMD_RESET);
DEBUG("isl29125_init: i2c_write_reg(ISL29125_REG_CONF1)\n");
(void) i2c_write_reg(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_CONF1, conf1);
/* release the I2C bus */
DEBUG("isl29125_init: i2c_release\n");
(void) i2c_release(dev->i2c);
DEBUG("isl29125_init: success\n");
return 0;
}
void isl29125_read_rgb_lux(isl29125_t *dev, isl29125_rgb_t *dest)
{
/* acquire exclusive access to the bus */
(void) i2c_acquire(dev->i2c);
/* read values */
char bytes[6];
(void) i2c_read_regs(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_GDLB, bytes, 6);
/* release the I2C bus */
(void) i2c_release(dev->i2c);
/* possibly shift by 4 to normalize 12 to 16 bit */
int resfactor = (dev->res == ISL29125_RESOLUTION_12) ? 4 : 0;
/* parse and normalize readings */
uint16_t green = (bytes[0] | (bytes[1] << 8)) << resfactor;
uint16_t red = (bytes[2] | (bytes[3] << 8)) << resfactor;
uint16_t blue = (bytes[4] | (bytes[5] << 8)) << resfactor;
DEBUG("isl29125_read_rgb: adjusted, unconverted readings: (%5i / %5i / %5i) \n", red, green, blue);
/* convert readings to lux */
float luxfactor = (dev->range == ISL29125_RANGE_10K) ? 10000.0 / 65535.0 : 375.0 / 65535.0;
dest->red = red * luxfactor;
dest->green = green * luxfactor;
dest->blue = blue * luxfactor;
}
void isl29125_read_rgb_color(isl29125_t *dev, color_rgb_t *dest)
{
/* acquire exclusive access to the bus */
(void) i2c_acquire(dev->i2c);
/* read values */
char bytes[6];
(void) i2c_read_regs(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_GDLB, bytes, 6);
/* release the I2C bus */
(void) i2c_release(dev->i2c);
/* factor normalize 12 or 16 bit to 8 bit */
int normfactor = (dev->res == ISL29125_RESOLUTION_12) ? 4 : 8;
/* parse and normalize readings */
dest->g = (bytes[0] | (bytes[1] << 8)) >> normfactor;
dest->r = (bytes[2] | (bytes[3] << 8)) >> normfactor;
dest->b = (bytes[4] | (bytes[5] << 8)) >> normfactor;
}
void isl29125_set_mode(isl29125_t *dev, isl29125_mode_t mode)
{
char conf1;
(void) i2c_acquire(dev->i2c);
(void) i2c_read_reg(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_CONF1, &conf1);
conf1 &= ~ISL29125_CON1_MASK_MODE;
conf1 |= mode;
(void) i2c_write_reg(dev->i2c, ISL29125_I2C_ADDRESS, ISL29125_REG_CONF1, conf1);
(void) i2c_release(dev->i2c);
}