QSerialPort in QThread - qt

Question

I was trying to read the serial output from a thread. The Serial port is opened in main program and passed the QSerialPort variable to thread.
Then I called serial.waitForReadyRead() function in thread, But its not getting any value from serial port. I confirmed that serial port is sending data by reading the same from main program.
Can anyone knows why this behavior is happening?
Adding the code below:
mainwindow.h
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
QSerialPort *serial;
private slots:
void onProgressChanged();
private:
Ui::MainWindow *ui;
};
class WorkerThread : public QThread {
Q_OBJECT
public:
QSerialPort *thread_serial;
void run() {
int ret = thread_serial->waitForReadyRead(60000); //thread is not getting any serial data.
//so it will not emit progressChanged.
if (ret)
{
qDebug()<<"Data Rate Read done";
QByteArray recvData = thread_serial->readAll();
qDebug()<<recvData;
emit progressChanged();
}
}
// Define signal:
signals:
void progressChanged();
};
mainwindow.cpp
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
serial = new QSerialPort(this);
openSerialPort( );
}
void MainWindow::openSerialPort( )
{
serial->setPortName("COM 4");
serial->setBaudRate(QSerialPort::Baud115200);
serial->setDataBits(QSerialPort::Data8);
serial->setParity(QSerialPort::NoParity);
serial->setStopBits(QSerialPort::OneStop);
serial->setFlowControl(QSerialPort::NoFlowControl);
if (serial->open(QIODevice::ReadWrite)) {
qDebug()<<"Connected";
WorkerThread *workerThread = new WorkerThread();
workerThread->thread_serial = serial;
connect(workerThread, SIGNAL(progressChanged()),
SLOT(onProgressChanged()));
workerThread->start();
}
}
void MainWindow::onProgressChanged()
{
qDebug()<<"inside onProgressChanged";
}