Qt BLE paring(bonding) problem.

[GoRo3]

Hi guys!

I'm developing own device based on nrf52840 MCU. It will communicate with my desktop client written in Qt 5.15. by BLE 5.2. For now i have done all data flow from connecting and communicating with device, but I'm stuck with bonding/paring problem.
Basically I need to bond or pair with MCU to add my client to whitelist, but by Qt side I have not found any useful (except bug reports) information how to force to pair after connecting to device. I tried to use QBluetoothLocalDevice but i'm getting all the time Paring Error.
This is code example from class that manages connecting and retrieving service information from MCU.

BtDeviceManager::BtDeviceManager(QObject *parent) : QObject(parent),
                                                    m_serializer(std::make_unique<FileSerializeService>()),
                                                    m_localDevice(this)
{
    connect(&m_localDevice, &QBluetoothLocalDevice::pairingFinished, [&](const QBluetoothAddress &address, QBluetoothLocalDevice::Pairing pairing){
       qDebug() << "Pairing has finished with status:" << pairing << " , " << "with address: " << address;
    });
    connect(&m_localDevice, &QBluetoothLocalDevice::error, [&](QBluetoothLocalDevice::Error error){
       qDebug() << "Pairing error" << error;
    });
    connect(&m_localDevice, &QBluetoothLocalDevice::pairingDisplayPinCode, [&](const QBluetoothAddress &address, QString pin){
       qDebug() << "Pairing confirmation is for device " << address <<  "is: " << pin;
    });
    connect(&m_localDevice, &QBluetoothLocalDevice::pairingDisplayPinCode, [&](const QBluetoothAddress &address, QString pin){
       qDebug() << "Pairing pin code for device " << address <<  "is: " << pin;
    });

    auto device = m_serializer.deserialize();
    if (device) {
        m_device = device;
        m_device->setManager(this);

        connectBt();
    }
}
void BtDeviceManager::connectBt()
{
    if (m_connectionController) {
        m_connectionController->disconnectFromDevice();
        delete m_connectionController;
        m_connectionController = nullptr;
    }


    m_connectionController = QLowEnergyController::createCentral(m_device->info().address(), m_localDevice.address(), this);

    connect(m_connectionController, &QLowEnergyController::serviceDiscovered,
            this, &BtDeviceManager::serviceDiscovered);
    connect(m_connectionController, &QLowEnergyController::discoveryFinished,
            this, &BtDeviceManager::serviceScanDone);

    connect(m_connectionController, static_cast<void (QLowEnergyController::*)(QLowEnergyController::Error)>(&QLowEnergyController::error),
            [&](QLowEnergyController::Error error) {
                Q_UNUSED(error);
                qWarning() << "Cannot connect to remote device. Error is: " << error;
            });
    connect(m_connectionController, &QLowEnergyController::connected, [&]() {
        qDebug() << "Controller connected. Search services...";
        m_connectedState = true;
        emit connectedStateChanged();
        m_connectionController->discoverServices();
    });
    connect(m_connectionController, &QLowEnergyController::disconnected, [&]() {
        qDebug() << "LowEnergy controller disconnected";
        m_connectedState = false;
        emit connectedStateChanged();
    });

    connect(m_connectionController, &QLowEnergyController::stateChanged, [&](auto newState){
        qDebug() << "LowEnergy controller state change to: " << newState;
    });

    // Connect

    QTimer::singleShot(10000, this, [&](){
        if(m_connectionController->state() == QLowEnergyController::ConnectingState) {
            m_connectionController->disconnectFromDevice();
            qDebug() << "Connection not handled, disconnecting";
        }
    });

    m_connectionController->connectToDevice();
}

I wonder is anybody have tried to make bonding or paring using Qt framework?

Best Regards!
GoRo3