ak09916.hpp

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#pragma once


#include <px4_platform_common/px4_config.h>
#include <lib/perf/perf_counter.h>
#include <systemlib/conversions.h>
#include <drivers/drv_hrt.h>
#include <drivers/device/i2c.h>
#include <px4_platform_common/px4_work_queue/ScheduledWorkItem.hpp>
#include <lib/drivers/magnetometer/PX4Magnetometer.hpp>

static constexpr auto AK09916_DEVICE_PATH_MAG = "/dev/ak09916_i2c_int";
static constexpr auto AK09916_DEVICE_PATH_MAG_EXT = "/dev/ak09916_i2c_ext";

// in 16-bit sampling mode the mag resolution is 1.5 milli Gauss per bit.
static constexpr float AK09916_MAG_RANGE_GA = 1.5e-3f;

static constexpr uint8_t AK09916_I2C_ADDR = 0x0C;

static constexpr uint8_t AK09916_DEVICE_ID_A = 0x48;
static constexpr uint8_t AK09916REG_WIA = 0x00;

static constexpr uint8_t AK09916REG_ST1 = 0x10;
static constexpr uint8_t AK09916REG_HXL = 0x11;
static constexpr uint8_t AK09916REG_CNTL2 = 0x31;
static constexpr uint8_t AK09916REG_CNTL3 = 0x32;

static constexpr uint8_t AK09916_RESET = 0x01;
static constexpr uint8_t AK09916_CNTL2_CONTINOUS_MODE_100HZ = 0x08;

static constexpr uint8_t AK09916_ST1_DRDY = 0x01;
static constexpr uint8_t AK09916_ST1_DOR = 0x02;

static constexpr uint8_t AK09916_ST2_HOFL = 0x08;

// Run at 100 Hz.
static constexpr unsigned AK09916_CONVERSION_INTERVAL_us = 1000000 / 100;

#pragma pack(push, 1)
struct ak09916_regs {
    int16_t x;
    int16_t y;
    int16_t z;
    uint8_t tmps;
    uint8_t st2;
};
#pragma pack(pop)


class AK09916 : public device::I2C, px4::ScheduledWorkItem
{
public:
    AK09916(int bus, const char *path, enum Rotation rotation);
    ~AK09916();

    virtual int init() override;
    void start();
    void stop();
    void print_info();
    int probe();

protected:
    int setup();
    int setup_master_i2c();
    bool check_id();
    void Run();
    void try_measure();
    bool is_ready();
    void measure();
    int reset();

    uint8_t read_reg(uint8_t reg);
    void read_block(uint8_t reg, uint8_t *val, uint8_t count);
    void write_reg(uint8_t reg, uint8_t value);

private:

    PX4Magnetometer _px4_mag;

    uint32_t _cycle_interval{0};

    perf_counter_t _mag_reads;
    perf_counter_t _mag_errors;
    perf_counter_t _mag_overruns;
    perf_counter_t _mag_overflows;

    AK09916(const AK09916 &) = delete;
    AK09916 operator=(const AK09916 &) = delete;
};