embox

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/**
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 * @file adxl345.c
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 * @brief G-Sensor
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 * @author Denis Deryugin <deryugin.denis@gmail.com>
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 * @version
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 * @date 17.12.2019
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 */
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#include <stdint.h>
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#include <drivers/i2c/i2c.h>
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#include <drivers/sensors/adxl345.h>
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#include <framework/mod/options.h>
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#include <util/log.h>
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#define ADXL345_DEVID           0x00
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#define ADXL345_OFSX            0x1E
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#define ADXL345_OFSY            0x1F
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#define ADXL345_OFSZ            0x20
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#define ADXL345_OFS_AXIS(index) (ADXL345_REG_OFSX + (index))
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#define ADXL345_BW_RATE         0x2C
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#define ADXL345_POWER_CTL       0x2D
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# define ADXL345_POWER_CTL_MSR  (1 << 3)
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#define ADXL345_DATA_FORMAT     0x31
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#define ADXL345_DATAX0          0x32
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#define ADXL345_DATAY0          0x34
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#define ADXL345_DATAZ0          0x36
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#define ADXL345_DATA_AXIS(n)    (ADXL345_DATAX0 + (n))
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#define ADXL345_DEVID_VALUE     0xE5
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#define ADXL345_BUS    OPTION_GET(NUMBER, bus)
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#define ADXL345_ADDR   OPTION_GET(NUMBER, addr)
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struct adxl345_dev {
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	int i2c_bus;
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	int i2c_addr;
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};
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/* Note: ADXL345 supports i2c and spi read/write ops,
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 * but for now we use only i2c bus */
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static uint8_t adxl345_readb(struct adxl345_dev *dev, int offset) {
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	uint8_t ret = offset;
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	i2c_bus_write(dev->i2c_bus, dev->i2c_addr, &ret, sizeof(ret));
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	i2c_bus_read(dev->i2c_bus, dev->i2c_addr, &ret, sizeof(ret));
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	return ret;
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}
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static void adxl345_writeb(struct adxl345_dev *dev, int offset, uint8_t val) {
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	uint16_t tmp = (offset & 0xFF) | (val << 8);
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	i2c_bus_write(dev->i2c_bus, dev->i2c_addr, (void *) &tmp, sizeof(tmp));
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}
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static struct adxl345_dev adxl345_dev = {
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	.i2c_bus  = ADXL345_BUS,
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	.i2c_addr = ADXL345_ADDR
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};
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int16_t adxl345_get_x(void) {
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	struct adxl345_dev *dev = &adxl345_dev;
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	return (int16_t) (adxl345_readb(dev, ADXL345_DATA_AXIS(0)) +
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		(adxl345_readb(dev, ADXL345_DATA_AXIS(1)) << 8));
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}
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int16_t adxl345_get_y(void) {
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	struct adxl345_dev *dev = &adxl345_dev;
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	return (int16_t) (adxl345_readb(dev, ADXL345_DATA_AXIS(2)) +
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		(adxl345_readb(dev, ADXL345_DATA_AXIS(3)) << 8));
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}
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int16_t adxl345_get_z(void) {
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	struct adxl345_dev *dev = &adxl345_dev;
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	return (int16_t) (adxl345_readb(dev, ADXL345_DATA_AXIS(4)) +
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		(adxl345_readb(dev, ADXL345_DATA_AXIS(5)) << 8));
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}
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int adxl345_init(void) {
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	uint8_t tmp;
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	struct adxl345_dev *dev = &adxl345_dev;
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	tmp = adxl345_readb(dev, ADXL345_DEVID);
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	if (tmp != ADXL345_DEVID_VALUE) {
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		log_error("ADXL345 Device ID mismatch! %2x", tmp);
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		return -1;
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	}
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	adxl345_writeb(dev, ADXL345_POWER_CTL,
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			ADXL345_POWER_CTL_MSR);
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	return 0;
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}
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