PAW3902.cpp

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/****************************************************************************
 *
 *   Copyright (c) 2019 PX4 Development Team. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
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 *    used to endorse or promote products derived from this software
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#include "PAW3902.hpp"

PAW3902::PAW3902(int bus, enum Rotation yaw_rotation) :
    SPI("PAW3902", nullptr, bus, PAW3902_SPIDEV, SPIDEV_MODE0, PAW3902_SPI_BUS_SPEED),
    ScheduledWorkItem(MODULE_NAME, px4::device_bus_to_wq(get_device_id())),
    _sample_perf(perf_alloc(PC_ELAPSED, "paw3902: read")),
    _comms_errors(perf_alloc(PC_COUNT, "paw3902: com_err")),
    _dupe_count_perf(perf_alloc(PC_COUNT, "paw3902: duplicate reading")),
    _yaw_rotation(yaw_rotation)
{
}

PAW3902::~PAW3902()
{
    // make sure we are truly inactive
    stop();

    // free perf counters
    perf_free(_sample_perf);
    perf_free(_comms_errors);
    perf_free(_dupe_count_perf);
}

int
PAW3902::init()
{
    // get yaw rotation from sensor frame to body frame
    param_t rot = param_find("SENS_FLOW_ROT");

    if (rot != PARAM_INVALID) {
        int32_t val = 0;

        if (param_get(rot, &val) == PX4_OK) {
            _yaw_rotation = (enum Rotation)val;
        }
    }

    /* For devices competing with NuttX SPI drivers on a bus (Crazyflie SD Card expansion board) */
    SPI::set_lockmode(LOCK_THREADS);

    /* do SPI init (and probe) first */
    if (SPI::init() != OK) {
        return PX4_ERROR;
    }

    reset();

    // default to low light mode (1)
    modeLowLight();

    _previous_collect_timestamp = hrt_absolute_time();

    start();

    return PX4_OK;
}

int
PAW3902::probe()
{
    uint8_t product_id = registerRead(Register::Product_ID);

    PX4_INFO("DEVICE_ID: %X", product_id);

    // Test the SPI communication, checking chipId and inverse chipId
    if (product_id != PRODUCT_ID) {
        return PX4_ERROR;
    }

    uint8_t revision_id = registerRead(Register::Revision_ID);
    PX4_INFO("REVISION_ID: %X", revision_id);

    if (revision_id != REVISION_ID) {
        return PX4_ERROR;
    }

    return PX4_OK;
}

bool
PAW3902::reset()
{
    // Power on reset
    registerWrite(Register::Power_Up_Reset, 0x5A);
    usleep(5000);

    // Read from registers 0x02, 0x03, 0x04, 0x05 and 0x06 one time regardless of the motion state
    registerRead(Register::Motion);
    registerRead(Register::Delta_X_L);
    registerRead(Register::Delta_X_H);
    registerRead(Register::Delta_Y_L);
    registerRead(Register::Delta_Y_H);

    usleep(1000);

    return true;
}

bool
PAW3902::changeMode(Mode newMode)
{
    if (newMode != _mode) {
        PX4_INFO("changing from mode %d -> %d", static_cast<int>(_mode), static_cast<int>(newMode));
        ScheduleClear();
        reset();

        switch (newMode) {
        case Mode::Bright:
            modeBright();
            ScheduleOnInterval(SAMPLE_INTERVAL_MODE_0);
            break;

        case Mode::LowLight:
            modeLowLight();
            ScheduleOnInterval(SAMPLE_INTERVAL_MODE_1);
            break;

        case Mode::SuperLowLight:
            modeSuperLowLight();
            ScheduleOnInterval(SAMPLE_INTERVAL_MODE_2);
            break;
        }

        _mode = newMode;
    }

    // Approximate Resolution = (Register Value + 1) * (50 / 8450) ≈ 0.6% of data point in Figure 19
    // The maximum register value is 0xA8. The minimum register value is 0.
    uint8_t resolution = registerRead(Register::Resolution);
    PX4_INFO("Resolution: %X", resolution);
    PX4_INFO("Resolution is approx: %.3f", (double)((resolution + 1.0f) * (50.0f / 8450.0f)));

    return true;
}

bool
PAW3902::modeBright()
{
    // Mode 0: Bright (126 fps) 60 Lux typical

    // set performance optimization registers
    registerWrite(0x7F, 0x00);
    registerWrite(0x55, 0x01);
    registerWrite(0x50, 0x07);
    registerWrite(0x7f, 0x0e);
    registerWrite(0x43, 0x10);

    registerWrite(0x48, 0x02);
    registerWrite(0x7F, 0x00);
    registerWrite(0x51, 0x7b);
    registerWrite(0x50, 0x00);
    registerWrite(0x55, 0x00);

    registerWrite(0x7F, 0x00);
    registerWrite(0x61, 0xAD);
    registerWrite(0x7F, 0x03);
    registerWrite(0x40, 0x00);
    registerWrite(0x7F, 0x05);
    registerWrite(0x41, 0xB3);
    registerWrite(0x43, 0xF1);
    registerWrite(0x45, 0x14);
    registerWrite(0x5F, 0x34);
    registerWrite(0x7B, 0x08);
    registerWrite(0x5e, 0x34);
    registerWrite(0x5b, 0x32);
    registerWrite(0x6d, 0x32);
    registerWrite(0x45, 0x17);
    registerWrite(0x70, 0xe5);
    registerWrite(0x71, 0xe5);
    registerWrite(0x7F, 0x06);
    registerWrite(0x44, 0x1B);
    registerWrite(0x40, 0xBF);
    registerWrite(0x4E, 0x3F);
    registerWrite(0x7F, 0x08);
    registerWrite(0x66, 0x44);
    registerWrite(0x65, 0x20);
    registerWrite(0x6a, 0x3a);
    registerWrite(0x61, 0x05);
    registerWrite(0x62, 0x05);
    registerWrite(0x7F, 0x09);
    registerWrite(0x4F, 0xAF);
    registerWrite(0x48, 0x80);
    registerWrite(0x49, 0x80);
    registerWrite(0x57, 0x77);
    registerWrite(0x5F, 0x40);
    registerWrite(0x60, 0x78);
    registerWrite(0x61, 0x78);
    registerWrite(0x62, 0x08);
    registerWrite(0x63, 0x50);
    registerWrite(0x7F, 0x0A);
    registerWrite(0x45, 0x60);
    registerWrite(0x7F, 0x00);
    registerWrite(0x4D, 0x11);
    registerWrite(0x55, 0x80);
    registerWrite(0x74, 0x21);
    registerWrite(0x75, 0x1F);
    registerWrite(0x4A, 0x78);
    registerWrite(0x4B, 0x78);
    registerWrite(0x44, 0x08);
    registerWrite(0x45, 0x50);
    registerWrite(0x64, 0xFE);
    registerWrite(0x65, 0x1F);
    registerWrite(0x72, 0x0A);
    registerWrite(0x73, 0x00);
    registerWrite(0x7F, 0x14);
    registerWrite(0x44, 0x84);
    registerWrite(0x65, 0x47);
    registerWrite(0x66, 0x18);
    registerWrite(0x63, 0x70);
    registerWrite(0x6f, 0x2c);
    registerWrite(0x7F, 0x15);
    registerWrite(0x48, 0x48);
    registerWrite(0x7F, 0x07);
    registerWrite(0x41, 0x0D);
    registerWrite(0x43, 0x14);
    registerWrite(0x4B, 0x0E);
    registerWrite(0x45, 0x0F);
    registerWrite(0x44, 0x42);
    registerWrite(0x4C, 0x80);
    registerWrite(0x7F, 0x10);
    registerWrite(0x5B, 0x03);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x41);

    usleep(10_ms); // delay 10ms

    registerWrite(0x7F, 0x00);
    registerWrite(0x32, 0x00);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x40);
    registerWrite(0x7F, 0x06);
    registerWrite(0x68, 0x70);
    registerWrite(0x69, 0x01);
    registerWrite(0x7F, 0x0D);
    registerWrite(0x48, 0xC0);
    registerWrite(0x6F, 0xD5);
    registerWrite(0x7F, 0x00);
    registerWrite(0x5B, 0xA0);
    registerWrite(0x4E, 0xA8);
    registerWrite(0x5A, 0x50);
    registerWrite(0x40, 0x80);
    registerWrite(0x73, 0x1f);

    usleep(10_ms); // delay 10ms

    registerWrite(0x73, 0x00);

    return false;
}

bool
PAW3902::modeLowLight()
{
    // Mode 1: Low Light (126 fps) 30 Lux typical
    // low light and low speed motion tracking

    // set performance optimization registers
    registerWrite(0x7F, 0x00);
    registerWrite(0x55, 0x01);
    registerWrite(0x50, 0x07);
    registerWrite(0x7f, 0x0e);
    registerWrite(0x43, 0x10);

    registerWrite(0x48, 0x02);
    registerWrite(0x7F, 0x00);
    registerWrite(0x51, 0x7b);
    registerWrite(0x50, 0x00);
    registerWrite(0x55, 0x00);

    registerWrite(0x7F, 0x00);
    registerWrite(0x61, 0xAD);
    registerWrite(0x7F, 0x03);
    registerWrite(0x40, 0x00);
    registerWrite(0x7F, 0x05);
    registerWrite(0x41, 0xB3);
    registerWrite(0x43, 0xF1);
    registerWrite(0x45, 0x14);
    registerWrite(0x5F, 0x34);
    registerWrite(0x7B, 0x08);
    registerWrite(0x5e, 0x34);
    registerWrite(0x5b, 0x65);
    registerWrite(0x6d, 0x65);
    registerWrite(0x45, 0x17);
    registerWrite(0x70, 0xe5);
    registerWrite(0x71, 0xe5);
    registerWrite(0x7F, 0x06);
    registerWrite(0x44, 0x1B);
    registerWrite(0x40, 0xBF);
    registerWrite(0x4E, 0x3F);
    registerWrite(0x7F, 0x08);
    registerWrite(0x66, 0x44);
    registerWrite(0x65, 0x20);
    registerWrite(0x6a, 0x3a);
    registerWrite(0x61, 0x05);
    registerWrite(0x62, 0x05);
    registerWrite(0x7F, 0x09);
    registerWrite(0x4F, 0xAF);
    registerWrite(0x48, 0x80);
    registerWrite(0x49, 0x80);
    registerWrite(0x57, 0x77);
    registerWrite(0x5F, 0x40);
    registerWrite(0x60, 0x78);
    registerWrite(0x61, 0x78);
    registerWrite(0x62, 0x08);
    registerWrite(0x63, 0x50);
    registerWrite(0x7F, 0x0A);
    registerWrite(0x45, 0x60);
    registerWrite(0x7F, 0x00);
    registerWrite(0x4D, 0x11);
    registerWrite(0x55, 0x80);
    registerWrite(0x74, 0x21);
    registerWrite(0x75, 0x1F);
    registerWrite(0x4A, 0x78);
    registerWrite(0x4B, 0x78);
    registerWrite(0x44, 0x08);
    registerWrite(0x45, 0x50);
    registerWrite(0x64, 0xFE);
    registerWrite(0x65, 0x1F);
    registerWrite(0x72, 0x0A);
    registerWrite(0x73, 0x00);
    registerWrite(0x7F, 0x14);
    registerWrite(0x44, 0x84);
    registerWrite(0x65, 0x67);
    registerWrite(0x66, 0x18);
    registerWrite(0x63, 0x70);
    registerWrite(0x6f, 0x2c);
    registerWrite(0x7F, 0x15);
    registerWrite(0x48, 0x48);
    registerWrite(0x7F, 0x07);
    registerWrite(0x41, 0x0D);
    registerWrite(0x43, 0x14);
    registerWrite(0x4B, 0x0E);
    registerWrite(0x45, 0x0F);
    registerWrite(0x44, 0x42);
    registerWrite(0x4C, 0x80);
    registerWrite(0x7F, 0x10);
    registerWrite(0x5B, 0x03);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x41);

    usleep(10_ms); // delay 10ms

    registerWrite(0x7F, 0x00);
    registerWrite(0x32, 0x00);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x40);
    registerWrite(0x7F, 0x06);
    registerWrite(0x68, 0x70);
    registerWrite(0x69, 0x01);
    registerWrite(0x7F, 0x0D);
    registerWrite(0x48, 0xC0);
    registerWrite(0x6F, 0xD5);
    registerWrite(0x7F, 0x00);
    registerWrite(0x5B, 0xA0);
    registerWrite(0x4E, 0xA8);
    registerWrite(0x5A, 0x50);
    registerWrite(0x40, 0x80);
    registerWrite(0x73, 0x1f);

    usleep(10_ms); // delay 10ms

    registerWrite(0x73, 0x00);

    return false;
}

bool
PAW3902::modeSuperLowLight()
{
    // Mode 2: Super Low Light (50 fps) 9 Lux typical
    // super low light and low speed motion tracking

    // set performance optimization registers
    registerWrite(0x7F, 0x00);
    registerWrite(0x55, 0x01);
    registerWrite(0x50, 0x07);
    registerWrite(0x7f, 0x0e);
    registerWrite(0x43, 0x10);

    registerWrite(0x48, 0x04);
    registerWrite(0x7F, 0x00);
    registerWrite(0x51, 0x7b);
    registerWrite(0x50, 0x00);
    registerWrite(0x55, 0x00);

    registerWrite(0x7F, 0x00);
    registerWrite(0x61, 0xAD);
    registerWrite(0x7F, 0x03);
    registerWrite(0x40, 0x00);
    registerWrite(0x7F, 0x05);
    registerWrite(0x41, 0xB3);
    registerWrite(0x43, 0xF1);
    registerWrite(0x45, 0x14);
    registerWrite(0x5F, 0x34);
    registerWrite(0x7B, 0x08);
    registerWrite(0x5E, 0x34);
    registerWrite(0x5B, 0x32);
    registerWrite(0x6D, 0x32);
    registerWrite(0x45, 0x17);
    registerWrite(0x70, 0xE5);
    registerWrite(0x71, 0xE5);
    registerWrite(0x7F, 0x06);
    registerWrite(0x44, 0x1B);
    registerWrite(0x40, 0xBF);
    registerWrite(0x4E, 0x3F);
    registerWrite(0x7F, 0x08);
    registerWrite(0x66, 0x44);
    registerWrite(0x65, 0x20);
    registerWrite(0x6A, 0x3a);
    registerWrite(0x61, 0x05);
    registerWrite(0x62, 0x05);
    registerWrite(0x7F, 0x09);
    registerWrite(0x4F, 0xAF);
    registerWrite(0x48, 0x80);
    registerWrite(0x49, 0x80);
    registerWrite(0x57, 0x77);
    registerWrite(0x5F, 0x40);
    registerWrite(0x60, 0x78);
    registerWrite(0x61, 0x78);
    registerWrite(0x62, 0x08);
    registerWrite(0x63, 0x50);
    registerWrite(0x7F, 0x0A);
    registerWrite(0x45, 0x60);
    registerWrite(0x7F, 0x00);
    registerWrite(0x4D, 0x11);
    registerWrite(0x55, 0x80);
    registerWrite(0x74, 0x21);
    registerWrite(0x75, 0x1F);
    registerWrite(0x4A, 0x78);
    registerWrite(0x4B, 0x78);
    registerWrite(0x44, 0x08);
    registerWrite(0x45, 0x50);
    registerWrite(0x64, 0xCE);
    registerWrite(0x65, 0x0B);
    registerWrite(0x72, 0x0A);
    registerWrite(0x73, 0x00);
    registerWrite(0x7F, 0x14);
    registerWrite(0x44, 0x84);
    registerWrite(0x65, 0x67);
    registerWrite(0x66, 0x18);
    registerWrite(0x63, 0x70);
    registerWrite(0x6f, 0x2c);
    registerWrite(0x7F, 0x15);
    registerWrite(0x48, 0x48);
    registerWrite(0x7F, 0x07);
    registerWrite(0x41, 0x0D);
    registerWrite(0x43, 0x14);
    registerWrite(0x4B, 0x0E);
    registerWrite(0x45, 0x0F);
    registerWrite(0x44, 0x42);
    registerWrite(0x4C, 0x80);
    registerWrite(0x7F, 0x10);
    registerWrite(0x5B, 0x02);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x41);

    usleep(25_ms); // delay 25ms

    registerWrite(0x7F, 0x00);
    registerWrite(0x32, 0x44);
    registerWrite(0x7F, 0x07);
    registerWrite(0x40, 0x40);
    registerWrite(0x7F, 0x06);
    registerWrite(0x68, 0x40);
    registerWrite(0x69, 0x02);
    registerWrite(0x7F, 0x0D);
    registerWrite(0x48, 0xC0);
    registerWrite(0x6F, 0xD5);
    registerWrite(0x7F, 0x00);
    registerWrite(0x5B, 0xA0);
    registerWrite(0x4E, 0xA8);
    registerWrite(0x5A, 0x50);
    registerWrite(0x40, 0x80);
    registerWrite(0x73, 0x0B);

    usleep(25_ms); // delay 25ms

    registerWrite(0x73, 0x00);

    return true;
}

uint8_t
PAW3902::registerRead(uint8_t reg)
{
    uint8_t cmd[2] {};
    cmd[0] = reg;
    transfer(&cmd[0], &cmd[0], sizeof(cmd));
    up_udelay(T_SRR);
    return cmd[1];
}

void
PAW3902::registerWrite(uint8_t reg, uint8_t data)
{
    uint8_t cmd[2];
    cmd[0] = DIR_WRITE(reg);
    cmd[1] = data;
    transfer(&cmd[0], nullptr, sizeof(cmd));
    up_udelay(T_SWW);
}

void
PAW3902::Run()
{
    perf_begin(_sample_perf);

    struct TransferBuffer {
        uint8_t cmd = Register::Motion_Burst;
        BURST_TRANSFER data{};
    };
    TransferBuffer buf;
    static_assert(sizeof(buf) == (12 + 1));

    const hrt_abstime timestamp_sample = hrt_absolute_time();

    if (transfer((uint8_t *)&buf, (uint8_t *)&buf, sizeof(buf)) != PX4_OK) {
        perf_count(_comms_errors);
        perf_end(_sample_perf);
        return;
    }

    const uint64_t dt_flow = timestamp_sample - _previous_collect_timestamp;
    _flow_dt_sum_usec += dt_flow;
    _frame_count_since_last++;

    // update for next iteration
    _previous_collect_timestamp = timestamp_sample;

    // PX4_INFO("data.Motion %d", buf.data.Motion);
    // PX4_INFO("data.Observation %d", buf.data.Observation);
    // PX4_INFO("data.Delta_X_L %d", buf.data.Delta_X_L);
    // PX4_INFO("data.Delta_X_H %d", buf.data.Delta_X_H);
    // PX4_INFO("data.Delta_Y_L %d", buf.data.Delta_Y_L);
    // PX4_INFO("data.Delta_Y_H %d", buf.data.Delta_Y_H);
    // PX4_INFO("data.SQUAL %d", buf.data.SQUAL);
    // PX4_INFO("data.RawData_Sum %d", buf.data.RawData_Sum);
    // PX4_INFO("data.Maximum_RawData %d", buf.data.Maximum_RawData);
    // PX4_INFO("data.Minimum_RawData %d", buf.data.Minimum_RawData);
    // PX4_INFO("data.Shutter_Upper %d", buf.data.Shutter_Upper);
    // PX4_INFO("data.Shutter_Lower %d", buf.data.Shutter_Lower);

    const int16_t delta_x_raw = ((int16_t)buf.data.Delta_X_H << 8) | buf.data.Delta_X_L;
    const int16_t delta_y_raw = ((int16_t)buf.data.Delta_Y_H << 8) | buf.data.Delta_Y_L;

    // check SQUAL & Shutter values
    // To suppress false motion reports, discard Delta X and Delta Y values if the SQUAL and Shutter values meet the condition
    // Bright Mode,         SQUAL < 0x19, Shutter ≥ 0x1FF0
    // Low Light Mode,      SQUAL < 0x46, Shutter ≥ 0x1FF0
    // Super Low Light Mode,    SQUAL < 0x55, Shutter ≥ 0x0BC0
    const uint16_t shutter = (buf.data.Shutter_Upper << 8) | buf.data.Shutter_Lower;

    if ((buf.data.SQUAL < 0x19) && (shutter >= 0x0BC0)) {
        PX4_ERR("false motion report, discarding");
        perf_end(_sample_perf);
        return;
    }

    switch (_mode) {
    case Mode::Bright:
        if ((shutter >= 0x1FFE) && (buf.data.RawData_Sum < 0x3C)) { // AND valid for 10 consecutive frames?
            // Bright -> LowLight
            changeMode(Mode::LowLight);
        }

        break;

    case Mode::LowLight:
        if ((shutter >= 0x1FFE) && (buf.data.RawData_Sum < 0x5A)) { // AND valid for 10 consecutive frames?
            // LowLight -> SuperLowLight
            changeMode(Mode::SuperLowLight);

        } else if ((shutter >= 0x0BB8)) {   // AND valid for 10 consecutive frames?
            // LowLight -> Bright
            changeMode(Mode::Bright);
        }

        break;

    case Mode::SuperLowLight:

        // SuperLowLight -> LowLight
        if ((shutter >= 0x03E8)) { // AND valid for 10 consecutive frames?
            changeMode(Mode::LowLight);
        }

        // PAW3902JF should not operate with Shutter < 0x01F4 in Mode 2
        if (shutter >= 0x01F4) {
            changeMode(Mode::LowLight);
        }

        break;
    }

    // TODO: page 35 switching scheme

    // As a minimum requirement, PAW3902JF should not operate with Shutter < 0x01F4 in Mode 2, and must switch to the next operation mode.

    _flow_sum_x += delta_x_raw;
    _flow_sum_y += delta_y_raw;

    // returns if the collect time has not been reached
    if (_flow_dt_sum_usec < _collect_time) {
        perf_end(_sample_perf);
        return;
    }

    optical_flow_s report{};
    report.timestamp = timestamp_sample;


    //PX4_INFO("X: %d Y: %d", _flow_sum_x, _flow_sum_y);

    report.pixel_flow_x_integral = (float)_flow_sum_x / 500.0f; // proportional factor + convert from pixels to radians
    report.pixel_flow_y_integral = (float)_flow_sum_y / 500.0f; // proportional factor + convert from pixels to radians

    // rotate measurements in yaw from sensor frame to body frame according to parameter SENS_FLOW_ROT
    float zeroval = 0.0f;
    rotate_3f(_yaw_rotation, report.pixel_flow_x_integral, report.pixel_flow_y_integral, zeroval);

    report.frame_count_since_last_readout = _frame_count_since_last;
    report.integration_timespan = _flow_dt_sum_usec;    // microseconds

    report.sensor_id = 0;
    report.quality = buf.data.SQUAL;

    /* No gyro on this board */
    report.gyro_x_rate_integral = NAN;
    report.gyro_y_rate_integral = NAN;
    report.gyro_z_rate_integral = NAN;

    // set (conservative) specs according to datasheet
    report.max_flow_rate = 5.0f;       // Datasheet: 7.4 rad/s
    report.min_ground_distance = 0.08f; // Datasheet: 80mm
    report.max_ground_distance = 30.0f; // Datasheet: infinity

    _optical_flow_pub.publish(report);

    // reset
    _flow_dt_sum_usec = 0;
    _flow_sum_x = 0;
    _flow_sum_y = 0;
    _frame_count_since_last = 0;

    perf_end(_sample_perf);
}

void
PAW3902::start()
{
    // schedule a cycle to start things
    ScheduleOnInterval(SAMPLE_INTERVAL_MODE_1);
}

void
PAW3902::stop()
{
    ScheduleClear();
}

void
PAW3902::print_info()
{
    perf_print_counter(_sample_perf);
    perf_print_counter(_comms_errors);
    perf_print_counter(_dupe_count_perf);
}