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/*
* Copyright (C) 2017 OTA keys S.A.
*
* 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 drivers_adcxx1x
* @{
*
* @file
* @brief ADCXX1C ADC device driver
*
* @author Vincent Dupont <vincent@otakeys.com>
* @}
*/
#include "adcxx1c.h"
#include "adcxx1c_params.h"
#include "adcxx1c_regs.h"
#include "periph/i2c.h"
#include "periph/gpio.h"
#define ENABLE_DEBUG (0)
#include "debug.h"
#define I2C_SPEED I2C_SPEED_FAST
#define I2C (dev->params.i2c)
#define ADDR (dev->params.addr)
/* Configuration register test value
* value 0x20: cycle time = Tconvert x 64 */
#define CONF_TEST_VALUE (0x20)
int adcxx1c_init(adcxx1c_t *dev, const adcxx1c_params_t *params)
{
assert(dev && params);
dev->params = *params;
dev->cb = NULL;
i2c_acquire(I2C);
if (i2c_init_master(I2C, I2C_SPEED) < 0) {
i2c_release(I2C);
DEBUG("[adcxx1c] init - error: unable to initialize I2C bus\n");
return ADCXX1C_NOI2C;
}
uint8_t reg = 0;
/* Test communication write and read configuration register */
i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, CONF_TEST_VALUE);
i2c_read_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, &reg);
if (reg != CONF_TEST_VALUE) {
i2c_release(I2C);
DEBUG("[adcxx1c] init - error: unable to communicate with the device (reg=%x)\n", reg);
return ADCXX1C_NODEV;
}
reg = dev->params.cycle << 5;
i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg);
i2c_release(I2C);
adcxx1c_set_alert_parameters(dev, dev->params.low_limit,
dev->params.high_limit,
dev->params.hysteresis);
return ADCXX1C_OK;
}
int adcxx1c_read_raw(const adcxx1c_t *dev, int16_t *raw)
{
uint8_t buf[2];
int status;
i2c_acquire(I2C);
status = i2c_read_regs(I2C, ADDR, ADCXX1C_CONV_RES_ADDR, buf, 2);
i2c_release(I2C);
if (status < 2) {
return ADCXX1C_NOI2C;
}
*raw = ((buf[0] & 0x0F) << 8 | buf[1]) >> (12 - dev->params.bits);
return ADCXX1C_OK;
}
static void _alert_cb(void *arg)
{
adcxx1c_t *dev = arg;
if (dev->cb) {
dev->cb(dev->arg);
}
}
int adcxx1c_enable_alert(adcxx1c_t *dev, adcxx1c_cb_t cb, void *arg)
{
uint8_t reg;
i2c_acquire(I2C);
i2c_read_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, &reg);
reg |= (dev->params.alert_pin != GPIO_UNDEF ? ADCXX1C_CONF_ALERT_PIN_EN : 0)
| ADCXX1C_CONF_ALERT_FLAG_EN;
i2c_write_reg(I2C, ADDR, ADCXX1C_CONF_ADDR, reg);
i2c_release(I2C);
if (dev->params.alert_pin != GPIO_UNDEF) {
dev->cb = cb;
dev->arg = arg;
/* alert active low */
gpio_init_int(dev->params.alert_pin, GPIO_IN, GPIO_FALLING, _alert_cb, dev);
}
return ADCXX1C_OK;
}
int adcxx1c_set_alert_parameters(const adcxx1c_t *dev, int16_t low_limit,
int16_t high_limit, int16_t hysteresis)
{
uint8_t buf[2];
i2c_acquire(I2C);
low_limit <<= (12 - dev->params.bits);
buf[0] = low_limit >> 8;
buf[1] = low_limit & 0xFF;
i2c_write_regs(I2C, ADDR, ADCXX1C_LOW_LIMIT_ADDR, buf, 2);
high_limit <<= (12 - dev->params.bits);
buf[0] = high_limit >> 8;
buf[1] = high_limit & 0xFF;
i2c_write_regs(I2C, ADDR, ADCXX1C_HIGH_LIMIT_ADDR, buf, 2);
hysteresis <<= (12 - dev->params.bits);
buf[0] = hysteresis >> 8;
buf[1] = hysteresis & 0xFF;
i2c_write_regs(I2C, ADDR, ADCXX1C_HYSTERESIS_ADDR, buf, 2);
i2c_release(I2C);
return ADCXX1C_OK;
}