serial_port.cpp

/****************************************************************************
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 *   Copyright (c) 2021 IMProject Development Team. All rights reserved.
 *   Authors: Igor Misic <igy1000mb@gmail.com>
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#include "serial_port.h"

#include <QDebug>
#include <QElapsedTimer>
#include <QSerialPortInfo>
#include <QThread>

namespace communication {
namespace {

constexpr int kMaxNoDataPeriod {10}; //!< Max time in [ms] while waiting for new serial data. 10 ms = 1 kHz for sender minimal task frequency.
constexpr int kSerialTimeoutInMs {100};
constexpr char kSoftwareTypeCmd[] = "software_type";
constexpr char kSwTypeImBoot[] = "IMBootloader";
constexpr char kSwTypeImApp[] = "IMApplication";

} // namespace

SerialPort::SerialPort() {
    connect(this, &communication::SerialPort::readyRead, this, &communication::SerialPort::ReadyRead);
}

SerialPort::~SerialPort() = default;

void SerialPort::ReadyRead() {
    serial_rx_data_.append(readAll());
}

void SerialPort::ReadData(QByteArray& data_out) {
    data_out = serial_rx_data_;
    serial_rx_data_.clear();
    previous_rx_data_size_ = 0;
}

void SerialPort::WaitForReadyRead(int timeout) {
    QElapsedTimer timer;
    timer.start();

    while (!timer.hasExpired(timeout)) {

        QObject().thread()->msleep(kMaxNoDataPeriod); // Give some time to the sender to send the data
        waitForReadyRead(1); //QSerial known workaround for triggering readyRead signal(https://bugreports.qt.io/browse/QTBUG-78086)

        int current_rx_data_size = serial_rx_data_.size();
        if ((current_rx_data_size == previous_rx_data_size_) && (current_rx_data_size != 0)) {
            // No new data. Ready to read, exit the loop.
            break;
        }

        previous_rx_data_size_ = current_rx_data_size;
    }
}

void SerialPort::CloseConn() {
    if (isOpen()) {
        close();
    }
}

bool SerialPort::DetectBoard(bool& is_bootloader) {
    bool is_board_detected;
    write(kSoftwareTypeCmd, sizeof(kSoftwareTypeCmd));
    WaitForReadyRead(kSerialTimeoutInMs);
    QByteArray data_out;
    ReadData(data_out);

    QString software_type = data_out;
    if (software_type == kSwTypeImApp) {
        is_bootloader = false;
        is_board_detected = true;
    } else if (software_type == kSwTypeImBoot) {
        is_bootloader = true;
        is_board_detected = true;

    } else {
        is_board_detected = false;
    }

    return is_board_detected;
}

bool SerialPort::OpenConnection(const QString& port_name) {
    if (port_name.isEmpty()) return false;

    setPortName(port_name);
    setBaudRate(QSerialPort::Baud115200);
    setDataBits(QSerialPort::Data8);
    setParity(QSerialPort::NoParity);

    setStopBits(QSerialPort::OneStop);
    setFlowControl(QSerialPort::NoFlowControl);

    return open(QIODevice::ReadWrite);
}

bool SerialPort::TryOpenPort(bool& is_bootloader) {
    const auto& infos = QSerialPortInfo::availablePorts();
    for (const auto& info : infos) {
        if (OpenConnection(info.portName())) {
            if (DetectBoard(is_bootloader)) return true;
            else CloseConn();
        }
    }

    return false;
}

} // namespace communication