mpu9250.h

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#pragma once

#include <lib/drivers/accelerometer/PX4Accelerometer.hpp>
#include <lib/drivers/gyroscope/PX4Gyroscope.hpp>
#include <lib/ecl/geo/geo.h>
#include <px4_platform_common/getopt.h>
#include <px4_platform_common/px4_work_queue/ScheduledWorkItem.hpp>
#include <lib/systemlib/conversions.h>
#include <lib/systemlib/px4_macros.h>

#include "MPU9250_mag.h"

#if defined(PX4_I2C_OBDEV_MPU9250) || defined(PX4_I2C_BUS_EXPANSION)
#  define USE_I2C
#endif


// MPU 9250 registers
#define MPUREG_WHOAMI           0x75
#define MPUREG_SMPLRT_DIV       0x19
#define MPUREG_CONFIG           0x1A
#define MPUREG_GYRO_CONFIG      0x1B
#define MPUREG_ACCEL_CONFIG     0x1C
#define MPUREG_ACCEL_CONFIG2        0x1D
#define MPUREG_LPACCEL_ODR      0x1E
#define MPUREG_WOM_THRESH       0x1F
#define MPUREG_FIFO_EN          0x23
#define MPUREG_I2C_MST_CTRL     0x24
#define MPUREG_I2C_SLV0_ADDR        0x25
#define MPUREG_I2C_SLV0_REG     0x26
#define MPUREG_I2C_SLV0_CTRL        0x27
#define MPUREG_I2C_SLV1_ADDR        0x28
#define MPUREG_I2C_SLV1_REG     0x29
#define MPUREG_I2C_SLV1_CTRL        0x2A
#define MPUREG_I2C_SLV2_ADDR        0x2B
#define MPUREG_I2C_SLV2_REG     0x2C
#define MPUREG_I2C_SLV2_CTRL        0x2D
#define MPUREG_I2C_SLV3_ADDR        0x2E
#define MPUREG_I2C_SLV3_REG     0x2F
#define MPUREG_I2C_SLV3_CTRL        0x30
#define MPUREG_I2C_SLV4_ADDR        0x31
#define MPUREG_I2C_SLV4_REG     0x32
#define MPUREG_I2C_SLV4_DO      0x33
#define MPUREG_I2C_SLV4_CTRL        0x34
#define MPUREG_I2C_SLV4_DI      0x35
#define MPUREG_I2C_MST_STATUS       0x36
#define MPUREG_INT_PIN_CFG      0x37
#define MPUREG_INT_ENABLE       0x38
#define MPUREG_INT_STATUS       0x3A
#define MPUREG_ACCEL_XOUT_H     0x3B
#define MPUREG_ACCEL_XOUT_L     0x3C
#define MPUREG_ACCEL_YOUT_H     0x3D
#define MPUREG_ACCEL_YOUT_L     0x3E
#define MPUREG_ACCEL_ZOUT_H     0x3F
#define MPUREG_ACCEL_ZOUT_L     0x40
#define MPUREG_TEMP_OUT_H       0x41
#define MPUREG_TEMP_OUT_L       0x42
#define MPUREG_GYRO_XOUT_H      0x43
#define MPUREG_GYRO_XOUT_L      0x44
#define MPUREG_GYRO_YOUT_H      0x45
#define MPUREG_GYRO_YOUT_L      0x46
#define MPUREG_GYRO_ZOUT_H      0x47
#define MPUREG_GYRO_ZOUT_L      0x48
#define MPUREG_EXT_SENS_DATA_00     0x49
#define MPUREG_I2C_SLV0_D0      0x63
#define MPUREG_I2C_SLV1_D0      0x64
#define MPUREG_I2C_SLV2_D0      0x65
#define MPUREG_I2C_SLV3_D0      0x66
#define MPUREG_I2C_MST_DELAY_CTRL   0x67
#define MPUREG_SIGNAL_PATH_RESET    0x68
#define MPUREG_MOT_DETECT_CTRL      0x69
#define MPUREG_USER_CTRL        0x6A
#define MPUREG_PWR_MGMT_1       0x6B
#define MPUREG_PWR_MGMT_2       0x6C
#define MPUREG_FIFO_COUNTH      0x72
#define MPUREG_FIFO_COUNTL      0x73
#define MPUREG_FIFO_R_W         0x74

// Configuration bits MPU 9250
#define BIT_SLEEP           0x40
#define BIT_H_RESET         0x80
#define MPU_CLK_SEL_AUTO        0x01

#define BITS_GYRO_ST_X          0x80
#define BITS_GYRO_ST_Y          0x40
#define BITS_GYRO_ST_Z          0x20
#define BITS_FS_250DPS          0x00
#define BITS_FS_500DPS          0x08
#define BITS_FS_1000DPS         0x10
#define BITS_FS_2000DPS         0x18
#define BITS_FS_MASK            0x18

#define BITS_DLPF_CFG_250HZ     0x00
#define BITS_DLPF_CFG_184HZ     0x01
#define BITS_DLPF_CFG_92HZ      0x02
#define BITS_DLPF_CFG_41HZ      0x03
#define BITS_DLPF_CFG_20HZ      0x04
#define BITS_DLPF_CFG_10HZ      0x05
#define BITS_DLPF_CFG_5HZ       0x06
#define BITS_DLPF_CFG_3600HZ        0x07
#define BITS_DLPF_CFG_MASK      0x07

#define BITS_ACCEL_CONFIG2_41HZ     0x03

#define BIT_RAW_RDY_EN          0x01
#define BIT_INT_ANYRD_2CLEAR        0x10
#define BIT_INT_BYPASS_EN       0x02

#define BIT_I2C_READ_FLAG           0x80

#define BIT_I2C_SLV0_NACK           0x01
#define BIT_I2C_FIFO_EN             0x40
#define BIT_I2C_MST_EN              0x20
#define BIT_I2C_IF_DIS              0x10
#define BIT_FIFO_RST                0x04
#define BIT_I2C_MST_RST             0x02
#define BIT_SIG_COND_RST            0x01

#define BIT_I2C_SLV0_EN             0x80
#define BIT_I2C_SLV0_BYTE_SW        0x40
#define BIT_I2C_SLV0_REG_DIS        0x20
#define BIT_I2C_SLV0_REG_GRP        0x10

#define BIT_I2C_MST_MULT_MST_EN     0x80
#define BIT_I2C_MST_WAIT_FOR_ES     0x40
#define BIT_I2C_MST_SLV_3_FIFO_EN   0x20
#define BIT_I2C_MST_P_NSR           0x10
#define BITS_I2C_MST_CLOCK_258HZ    0x08
#define BITS_I2C_MST_CLOCK_400HZ    0x0D

#define BIT_I2C_SLV0_DLY_EN         0x01
#define BIT_I2C_SLV1_DLY_EN         0x02
#define BIT_I2C_SLV2_DLY_EN         0x04
#define BIT_I2C_SLV3_DLY_EN         0x08

#define MPU_WHOAMI_9250             0x71
#define MPU_WHOAMI_6500             0x70

#define MPU9250_ACCEL_DEFAULT_RATE  1000
#define MPU9250_ACCEL_MAX_OUTPUT_RATE           280
#define MPU9250_ACCEL_DEFAULT_DRIVER_FILTER_FREQ 30
#define MPU9250_GYRO_DEFAULT_RATE   1000
/* rates need to be the same between accel and gyro */
#define MPU9250_GYRO_MAX_OUTPUT_RATE            MPU9250_ACCEL_MAX_OUTPUT_RATE
#define MPU9250_GYRO_DEFAULT_DRIVER_FILTER_FREQ 30

#define MPU9250_DEFAULT_ONCHIP_FILTER_FREQ  92

#pragma pack(push, 1)
/**
 * Report conversation within the mpu, including command byte and
 * interrupt status.
 */
struct MPUReport {
    uint8_t     cmd;
    uint8_t     status;
    uint8_t     accel_x[2];
    uint8_t     accel_y[2];
    uint8_t     accel_z[2];
    uint8_t     temp[2];
    uint8_t     gyro_x[2];
    uint8_t     gyro_y[2];
    uint8_t     gyro_z[2];
    struct ak8963_regs mag;
};
#pragma pack(pop)

/*
  The MPU9250 can only handle high bus speeds on the sensor and
  interrupt status registers. All other registers have a maximum 1MHz
  Communication with all registers of the device is performed using either
  I2C at 400kHz or SPI at 1MHz. For applications requiring faster communications,
  the sensor and interrupt registers may be read using SPI at 20MHz
 */
#define MPU9250_LOW_BUS_SPEED               0
#define MPU9250_HIGH_BUS_SPEED              0x8000
#define MPU9250_REG_MASK                    0x00FF
#  define MPU9250_IS_HIGH_SPEED(r)          ((r) & MPU9250_HIGH_BUS_SPEED)
#  define MPU9250_REG(r)                    ((r) & MPU9250_REG_MASK)
#  define MPU9250_SET_SPEED(r, s)           ((r)|(s))
#  define MPU9250_HIGH_SPEED_OP(r)          MPU9250_SET_SPEED((r), MPU9250_HIGH_BUS_SPEED)
#  define MPU9250_LOW_SPEED_OP(r)           ((r) &~MPU9250_HIGH_BUS_SPEED)

/* interface factories */
extern device::Device *MPU9250_SPI_interface(int bus, uint32_t cs);
extern device::Device *MPU9250_I2C_interface(int bus, uint32_t address);
extern int MPU9250_probe(device::Device *dev);

typedef device::Device *(*MPU9250_constructor)(int, uint32_t);

class MPU9250_mag;

class MPU9250 : public px4::ScheduledWorkItem
{
public:
    MPU9250(device::Device *interface, device::Device *mag_interface, enum Rotation rotation);
    virtual ~MPU9250();

    virtual int     init();
    uint8_t         get_whoami() { return _whoami; }

    /**
     * Diagnostics - print some basic information about the driver.
     */
    void            print_info();

protected:
    device::Device *_interface;
    uint8_t         _whoami{0}; /** whoami result */

    virtual int     probe();

    friend class MPU9250_mag;

    void Run() override;

private:

    PX4Accelerometer    _px4_accel;
    PX4Gyroscope        _px4_gyro;

    MPU9250_mag     _mag;

    unsigned        _call_interval{1000};

    unsigned        _dlpf_freq{0};

    unsigned        _sample_rate{1000};

    perf_counter_t      _sample_perf;
    perf_counter_t      _bad_transfers;
    perf_counter_t      _bad_registers;
    perf_counter_t      _good_transfers;
    perf_counter_t      _duplicates;

    uint8_t         _register_wait{0};
    uint64_t        _reset_wait{0};

    // this is used to support runtime checking of key
    // configuration registers to detect SPI bus errors and sensor
    // reset

    static constexpr int MPU9250_NUM_CHECKED_REGISTERS{11};
    static const uint16_t _mpu9250_checked_registers[MPU9250_NUM_CHECKED_REGISTERS];

    const uint16_t          *_checked_registers{nullptr};

    uint8_t                 _checked_values[MPU9250_NUM_CHECKED_REGISTERS] {};
    uint8_t                 _checked_bad[MPU9250_NUM_CHECKED_REGISTERS] {};
    unsigned                _checked_next{0};
    unsigned                _num_checked_registers{0};


    // last temperature reading for print_info()
    float           _last_temperature{0.0f};

    bool check_null_data(uint16_t *data, uint8_t size);
    bool check_duplicate(uint8_t *accel_data);

    // keep last accel reading for duplicate detection
    uint8_t         _last_accel_data[6] {};
    bool            _got_duplicate{false};

    void            start();
    void            stop();
    int         reset();

    /**
     * Resets the main chip (excluding the magnetometer if any).
     */
    int         reset_mpu();

    /**
     * Fetch measurements from the sensor and update the report buffers.
     */
    void            measure();

    /**
     * Read a register from the mpu
     *
     * @param       The register to read.
    * @param       The bus speed to read with.
     * @return      The value that was read.
     */
    uint8_t         read_reg(unsigned reg, uint32_t speed = MPU9250_LOW_BUS_SPEED);
    uint16_t        read_reg16(unsigned reg);


    /**
     * Read a register range from the mpu
     *
     * @param       The start address to read from.
     * @param       The bus speed to read with.
     * @param       The address of the target data buffer.
     * @param       The count of bytes to be read.
     * @return      The value that was read.
     */
    uint8_t read_reg_range(unsigned start_reg, uint32_t speed, uint8_t *buf, uint16_t count);

    /**
     * Write a register in the mpu
     *
     * @param reg       The register to write.
     * @param value     The new value to write.
     */
    void            write_reg(unsigned reg, uint8_t value);

    /**
     * Modify a register in the mpu
     *
     * Bits are cleared before bits are set.
     *
     * @param reg       The register to modify.
     * @param clearbits Bits in the register to clear.
     * @param setbits   Bits in the register to set.
     */
    void            modify_reg(unsigned reg, uint8_t clearbits, uint8_t setbits);

    /**
     * Write a register in the mpu, updating _checked_values
     *
     * @param reg       The register to write.
     * @param value     The new value to write.
     */
    void            write_checked_reg(unsigned reg, uint8_t value);

    /**
     * Modify a checked register in the mpu
     *
     * Bits are cleared before bits are set.
     *
     * @param reg       The register to modify.
     * @param clearbits Bits in the register to clear.
     * @param setbits   Bits in the register to set.
     */
    void            modify_checked_reg(unsigned reg, uint8_t clearbits, uint8_t setbits);

    /**
     * Set the mpu measurement range.
     *
     * @param max_g     The maximum G value the range must support.
     * @return      OK if the value can be supported, -ERANGE otherwise.
     */
    int         set_accel_range(unsigned max_g);

    /**
     * Swap a 16-bit value read from the mpu to native byte order.
     */
    uint16_t        swap16(uint16_t val) { return (val >> 8) | (val << 8);  }

    /**
     * Get the internal / external state
     *
     * @return true if the sensor is not on the main MCU board
     */
    bool            is_external() { return _interface->external(); }

    /*
      set low pass filter frequency
     */
    void _set_dlpf_filter(uint16_t frequency_hz);

    /*
      set sample rate (approximate) - 1kHz to 5Hz
    */
    void _set_sample_rate(unsigned desired_sample_rate_hz);

    /*
      check that key registers still have the right value
     */
    void check_registers();
};