MPU9250_mag.h

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#pragma once

#include <perf/perf_counter.h>
#include <lib/drivers/magnetometer/PX4Magnetometer.hpp>
#include <drivers/device/Device.hpp>

/* in 16-bit sampling mode the mag resolution is 1.5 milli Gauss per bit */
static constexpr float MPU9250_MAG_RANGE_GA{1.5e-3f};

/* ak8963 register address and bit definitions */
#define AK8963_I2C_ADDR         0x0C
#define AK8963_DEVICE_ID        0x48

#define AK8963REG_WIA           0x00
#define AK8963REG_ST1           0x02
#define AK8963REG_HXL           0x03
#define AK8963REG_ASAX          0x10
#define AK8963REG_CNTL1         0x0A
#define AK8963REG_CNTL2         0x0B

#define AK8963_SINGLE_MEAS_MODE 0x01
#define AK8963_CONTINUOUS_MODE1 0x02
#define AK8963_CONTINUOUS_MODE2 0x06
#define AK8963_POWERDOWN_MODE   0x00
#define AK8963_SELFTEST_MODE    0x08
#define AK8963_FUZE_MODE        0x0F
#define AK8963_16BIT_ADC        0x10
#define AK8963_14BIT_ADC        0x00
#define AK8963_RESET            0x01
#define AK8963_HOFL             0x08

/* ak09916 deviating register addresses and bit definitions */

#define AK09916_DEVICE_ID_A     0x48    // same as AK8963
#define AK09916_DEVICE_ID_B     0x09    // additional ID byte ("INFO" on AK9063 without content specification.)

#define AK09916REG_HXL        0x11
#define AK09916REG_HXH        0x12
#define AK09916REG_HYL        0x13
#define AK09916REG_HYH        0x14
#define AK09916REG_HZL        0x15
#define AK09916REG_HZH        0x16
#define AK09916REG_ST1        0x10
#define AK09916REG_ST2        0x18
#define AK09916REG_CNTL2          0x31
#define AK09916REG_CNTL3          0x32


#define AK09916_CNTL2_POWERDOWN_MODE            0x00
#define AK09916_CNTL2_SINGLE_MODE               0x01 /* default */
#define AK09916_CNTL2_CONTINOUS_MODE_10HZ       0x02
#define AK09916_CNTL2_CONTINOUS_MODE_20HZ       0x04
#define AK09916_CNTL2_CONTINOUS_MODE_50HZ       0x06
#define AK09916_CNTL2_CONTINOUS_MODE_100HZ      0x08
#define AK09916_CNTL2_SELFTEST_MODE             0x10
#define AK09916_CNTL3_SRST                      0x01
#define AK09916_ST1_DRDY                        0x01
#define AK09916_ST1_DOR                         0x02

class MPU9250;

#pragma pack(push, 1)
struct ak8963_regs {
    uint8_t st1;
    int16_t x;
    int16_t y;
    int16_t z;
    uint8_t st2;
};
#pragma pack(pop)

extern device::Device *AK8963_I2C_interface(int bus);

typedef device::Device *(*MPU9250_mag_constructor)(int, bool);

/**
 * Helper class implementing the magnetometer driver node.
 */
class MPU9250_mag
{
public:
    MPU9250_mag(MPU9250 *parent, device::Device *interface, enum Rotation rotation);
    ~MPU9250_mag();

    void set_passthrough(uint8_t reg, uint8_t size, uint8_t *out = NULL);
    void passthrough_read(uint8_t reg, uint8_t *buf, uint8_t size);
    void passthrough_write(uint8_t reg, uint8_t val);
    void read_block(uint8_t reg, uint8_t *val, uint8_t count);

    int ak8963_reset();
    int ak8963_setup();
    int ak8963_setup_master_i2c();
    bool ak8963_check_id(uint8_t &id);
    bool ak8963_read_adjustments();

    void print_status() { _px4_mag.print_status(); }

protected:
    device::Device          *_interface;

    friend class MPU9250;

    void measure();
    void _measure(hrt_abstime timestamp_sample, ak8963_regs data);

    uint8_t read_reg(unsigned reg);
    void write_reg(unsigned reg, uint8_t value);

    bool is_passthrough() { return _interface == nullptr; }

private:
    PX4Magnetometer     _px4_mag;

    MPU9250 *_parent;

    bool _mag_reading_data{false};

    perf_counter_t _mag_overruns;
    perf_counter_t _mag_overflows;
    perf_counter_t _mag_errors;

};