LPS22HB_I2C.cpp 3.14 KB
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/**
 * @file lps22hb_i2c.cpp
 *
 * I2C interface for lps22hb
 */

#include "LPS22HB.hpp"

#include <drivers/device/i2c.h>

#define LPS22HB_ADDRESS		0x5D

device::Device *LPS22HB_I2C_interface(int bus, int bus_frequency);

class LPS22HB_I2C : public device::I2C
{
public:
	LPS22HB_I2C(int bus, int bus_frequency);
	~LPS22HB_I2C() override = default;

	int	read(unsigned address, void *data, unsigned count) override;
	int	write(unsigned address, void *data, unsigned count) override;

protected:
	int	probe() override;

};

device::Device *
LPS22HB_I2C_interface(int bus, int bus_frequency)
{
	return new LPS22HB_I2C(bus, bus_frequency);
}

LPS22HB_I2C::LPS22HB_I2C(int bus, int bus_frequency) :
	I2C(DRV_BARO_DEVTYPE_LPS22HB, MODULE_NAME, bus, LPS22HB_ADDRESS, bus_frequency)
{
}

int LPS22HB_I2C::probe()
{
	uint8_t id = 0;

	_retries = 10;

	if (read(WHO_AM_I, &id, 1)) {
		DEVICE_DEBUG("read_reg fail");
		return -EIO;
	}

	_retries = 2;

	if (id != LPS22HB_ID_WHO_AM_I) {
		DEVICE_DEBUG("ID byte mismatch (%02x != %02x)", LPS22HB_ID_WHO_AM_I, id);
		return -EIO;
	}

	return PX4_OK;
}

int LPS22HB_I2C::write(unsigned address, void *data, unsigned count)
{
	uint8_t buf[32];

	if (sizeof(buf) < (count + 1)) {
		return -EIO;
	}

	buf[0] = address;
	memcpy(&buf[1], data, count);

	return transfer(&buf[0], count + 1, nullptr, 0);
}

int
LPS22HB_I2C::read(unsigned address, void *data, unsigned count)
{
	uint8_t cmd = address;
	return transfer(&cmd, 1, (uint8_t *)data, count);
}