LidarLiteI2C.h

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#pragma once

#include "LidarLite.h"

#include <px4_workqueue.h>

#include <perf/perf_counter.h>

#include <drivers/device/i2c.h>
#include <drivers/device/ringbuffer.h>

#include <uORB/uORB.h>
#include <uORB/topics/distance_sensor.h>


/* Configuration Constants */
#define LL40LS_BASEADDR     0x62 /* 7-bit address */
#define LL40LS_BASEADDR_OLD     0x42 /* previous 7-bit address */

/* LL40LS Registers addresses */

#define LL40LS_MEASURE_REG      0x00        /* Measure range register */
#define LL40LS_MSRREG_RESET     0x00        /* reset to power on defaults */
#define LL40LS_MSRREG_ACQUIRE       0x04        /* Value to initiate a measurement, varies based on sensor revision */
#define LL40LS_DISTHIGH_REG     0x0F        /* High byte of distance register, auto increment */
#define LL40LS_AUTO_INCREMENT   0x80
#define LL40LS_HW_VERSION         0x41
#define LL40LS_SW_VERSION         0x4f
#define LL40LS_SIGNAL_STRENGTH_REG  0x0e
#define LL40LS_PEAK_STRENGTH_REG  0x0c
#define LL40LS_UNIT_ID_HIGH 0x16
#define LL40LS_UNIT_ID_LOW 0x17

#define LL40LS_SIG_COUNT_VAL_REG      0x02        /* Maximum acquisition count register */
#define LL40LS_SIG_COUNT_VAL_MAX     0xFF        /* Maximum acquisition count max value */

#define LL40LS_SIGNAL_STRENGTH_LOW 24           // Minimum (relative) signal strength value for accepting a measurement
#define LL40LS_PEAK_STRENGTH_LOW 135            // Minimum peak strength raw value for accepting a measurement
#define LL40LS_PEAK_STRENGTH_HIGH 234           // Max peak strength raw value

class LidarLiteI2C : public LidarLite, public device::I2C
{
public:
    LidarLiteI2C(int bus, const char *path,
             uint8_t rotation = distance_sensor_s::ROTATION_DOWNWARD_FACING,
             int address = LL40LS_BASEADDR);
    virtual ~LidarLiteI2C();

    int         init() override;

    ssize_t     read(device::file_t *filp, char *buffer, size_t buflen) override;
    int         ioctl(device::file_t *filp, int cmd, unsigned long arg) override;

    void print_info() override;

    void print_registers() override;

    const char *get_dev_name() override;

protected:
    int         probe() override;
    int         read_reg(uint8_t reg, uint8_t &val);
    int         write_reg(uint8_t reg, uint8_t val);

    int                 measure() override;
    int                 reset_sensor() override;

private:
    uint8_t _rotation;
    work_s              _work;
    ringbuffer::RingBuffer          *_reports;
    bool                _sensor_ok;
    bool                _collect_phase;
    int                 _class_instance;
    int         _orb_class_instance;

    orb_advert_t        _distance_sensor_topic;

    perf_counter_t      _sample_perf;
    perf_counter_t      _comms_errors;
    perf_counter_t      _sensor_resets;
    perf_counter_t      _sensor_zero_resets;
    uint16_t        _last_distance;
    uint16_t        _zero_counter;
    uint64_t        _acquire_time_usec;
    volatile bool       _pause_measurements;
    uint8_t     _hw_version;
    uint8_t     _sw_version;
    uint16_t    _unit_id;

    int lidar_transfer(const uint8_t *send, unsigned send_len, uint8_t *recv, unsigned recv_len);

    int                 probe_address(uint8_t address);

    void                start() override;

    void                stop() override;

    void                cycle();
    int                 collect() override;

    static void     cycle_trampoline(void *arg);

private:
    LidarLiteI2C(const LidarLiteI2C &copy) = delete;
    LidarLiteI2C operator=(const LidarLiteI2C &assignment) = delete;
};