FXAS21002C.hpp

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/**
 * @file FXAS21002C.hpp
 * Driver for the NXP FXAS21002C 3-Axis Digital Angular Rate Gyroscope
 * connected via SPI
 */

#pragma once

#include <drivers/device/spi.h>
#include <lib/drivers/gyroscope/PX4Gyroscope.hpp>
#include <perf/perf_counter.h>
#include <px4_platform_common/getopt.h>
#include <px4_platform_common/px4_work_queue/ScheduledWorkItem.hpp>


class FXAS21002C : public device::SPI, public px4::ScheduledWorkItem
{
public:
    FXAS21002C(int bus, uint32_t device, enum Rotation rotation);
    virtual ~FXAS21002C();

    virtual int init();

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

    /**
     * dump register values
     */
    void print_registers();

    /**
     * deliberately trigger an error
     */
    void test_error();

protected:
    virtual int probe();

private:

    PX4Gyroscope _px4_gyro;

    unsigned _current_rate{800};

    unsigned _read{0};

    perf_counter_t _sample_perf;
    perf_counter_t _errors;
    perf_counter_t _bad_registers;
    perf_counter_t _duplicates;

    uint8_t _register_wait{0};

    /* this is used to support runtime checking of key
     *configuration registers to detect SPI bus errors and sensor
     * reset
     */
    static constexpr int FXAS21002C_NUM_CHECKED_REGISTERS{6};

    uint8_t _checked_values[FXAS21002C_NUM_CHECKED_REGISTERS] {};
    uint8_t _checked_next{0};

    /**
     * Start automatic measurement.
     */
    void start();

    /**
     * Stop automatic measurement.
     */
    void stop();

    /**
     * Reset chip.
     *
     * Resets the chip and measurements ranges, but not scale and offset.
     */
    void reset();

    /**
     * Put the chip In stand by
     */
    void set_standby(int rate, bool standby_true);

    void Run() override;

    /**
     * check key registers for correct values
     */
    void check_registers(void);

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

    /**
     * Read a register from the FXAS21002C
     *
     * @param       The register to read.
     * @return      The value that was read.
     */
    uint8_t read_reg(unsigned reg);

    /**
     * Write a register in the FXAS21002C
     *
     * @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 FXAS21002C
     *
     * 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 FXAS21002C, 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);

    /**
     * Set the FXAS21002C measurement range.
     *
     * @param max_dps   The measurement range is set to permit reading at least
     *          this rate in degrees per second.
     *          Zero selects the maximum supported range.
     * @return      OK if the value can be supported, -ERANGE otherwise.
     */
    int set_range(unsigned max_dps);

    /**
     * Set the FXAS21002C internal sampling frequency.
     *
     * @param frequency The internal sampling frequency is set to not less than
     *          this value.
     *          Zero selects the maximum rate supported.
     * @return      OK if the value can be supported.
     */
    int set_samplerate(unsigned frequency);

    /*
      set onchip low pass filter frequency
     */
    void set_onchip_lowpass_filter(int frequency_hz);
};