Add a touchscreen generic qpa plugin.

Change-Id: Iaf79df05eb4f60d254d95f5d0f280a8f8f8a8de8
Reviewed-on: http://codereview.qt.nokia.com/941
Reviewed-by: Jørgen Lind <jorgen.lind@nokia.com>

src/plugins/generic/touchscreen/70-qtouchscreen.rules

@@ -0,0 +1 @@
+KERNEL=="event*", ENV{ID_INPUT_TOUCHPAD}=="1", ENV{QT_TOUCH}="1", MODE="0644"

src/plugins/generic/touchscreen/README

@@ -0,0 +1,45 @@
+Generic plug-in for evdev touch events
+
+(a) Using as a QPA generic plug-in
+
+1. set up the touch device
+2. sudo apt-get install libmtdev-dev libudev-dev
+3. build this plug-in (qmake && make)
+4. sudo cp 70-qtouchscreen.rules /etc/udev/rules.d
+5. sudo udevadm trigger --subsystem-match=input
+6. run apps like this: app -platform xcb -plugin LinuxTouchScreen
+
+If automatic detection does not work, use -plugin
+LinuxTouchScreen:/dev/input/eventN to explicitly set the device file
+name.
+
+By default the surface of the touch device is mapped to the entire
+screen. If this is not desired, define FORCE_TO_ACTIVE_WINDOW in
+qtoucheventsenderqpa.cpp. This will map the touch surface to the
+active window instead.
+
+Only touch events are generated (via
+QWindowSystemInterface::handleTouchEvent), mouse events are not. This
+is because on desktop the touch device will usually act as a
+single-touch mouse replacement anyway. For pointer-less systems the
+code needs to be extended to generate also mouse events (by calling
+handleMouseEvent too).
+
+(b) Using in a compositor
+
+The classes (QTouchScreenHandler, QTouchScreenHandlerThread) are also
+suitable for direct inclusion into an application, e.g. a Wayland
+compositor. The compositor will then usually register its own
+QTouchScreenObserver because relying on the QTouchEvents generated by
+the QPA event sender is often not satisfactory, as some low-level
+details may get lost, and due to performance reasons.
+
+
+Known issues:
+
+The udev rule matches any touchpad device. If there are multiple ones,
+specify the device as described above.
+
+On recent distributions (e.g. Ubuntu 11.04) you may need to remove
+50-synaptics.conf from /usr/share/X11/xorg.conf.d (followed by
+logout/login) otherwise no evdev events can be read.

src/plugins/generic/touchscreen/main.cpp

@@ -0,0 +1,80 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <qgenericplugin_qpa.h>
+#include "qtouchscreen.h"
+#include "qtoucheventsenderqpa.h"
+
+QT_BEGIN_NAMESPACE
+
+class QTouchScreenPlugin : public QGenericPlugin
+{
+public:
+    QTouchScreenPlugin();
+
+    QStringList keys() const;
+    QObject* create(const QString &key, const QString &specification);
+};
+
+QTouchScreenPlugin::QTouchScreenPlugin()
+{
+}
+
+QStringList QTouchScreenPlugin::keys() const
+{
+    return QStringList() << "LinuxTouchScreen";
+}
+
+QObject* QTouchScreenPlugin::create(const QString &key,
+                                   const QString &spec)
+{
+    if (!key.compare(QLatin1String("LinuxTouchScreen"), Qt::CaseInsensitive)) {
+        QTouchScreenHandler *h = new QTouchScreenHandler(spec);
+        h->addObserver(new QTouchEventSenderQPA);
+        return h;
+    }
+
+    return 0;
+    }
+
+Q_EXPORT_PLUGIN2(qtouchscreenplugin, QTouchScreenPlugin)
+
+QT_END_NAMESPACE

src/plugins/generic/touchscreen/qtoucheventsenderqpa.cpp

@@ -0,0 +1,113 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qtoucheventsenderqpa.h"
+#include <QApplication>
+#include <QDesktopWidget>
+#include <QDebug>
+
+QT_BEGIN_NAMESPACE
+
+//#define POINT_DEBUG
+//#define FORCE_TO_ACTIVE_WINDOW
+
+void QTouchEventSenderQPA::touch_configure(int x_min, int x_max, int y_min, int y_max)
+{
+    hw_range_x_min = x_min;
+    hw_range_x_max = x_max;
+    hw_range_y_min = y_min;
+    hw_range_y_max = y_max;
+}
+
+void QTouchEventSenderQPA::touch_point(QEvent::Type state,
+                                       const QList<QWindowSystemInterface::TouchPoint> &points)
+{
+#ifdef FORCE_TO_ACTIVE_WINDOW
+    QWidget *win = QApplication::activeWindow(); // ### migrate to QWindow later on
+    if (!win) {
+#ifdef POINT_DEBUG
+        qDebug("sendTouchEvent: No active window");
+#endif
+        return;
+    }
+    const QRect winRect = win->geometry();
+#else
+    const QRect winRect = QApplication::desktop()->screenGeometry();
+#endif
+
+#ifdef POINT_DEBUG
+    qDebug() << points.size() << "points" << winRect << state;
+#endif
+
+    QList<QWindowSystemInterface::TouchPoint> touchPoints = points;
+    // Translate the coordinates and set the normalized position. QPA expects
+    // 'area' to be in screen coordinates, while the device reports them in its
+    // own system with (0, 0) being the center point of the device.
+    for (int i = 0; i < touchPoints.size(); ++i) {
+        QWindowSystemInterface::TouchPoint &tp(touchPoints[i]);
+
+        // Translate so that (0, 0) is the top-left corner.
+        const int hw_x = qBound(hw_range_x_min, int(tp.area.left()), hw_range_x_max) - hw_range_x_min;
+        const int hw_y = qBound(hw_range_y_min, int(tp.area.top()), hw_range_y_max) - hw_range_y_min;
+
+        // Get a normalized position in range 0..1.
+        const int hw_w = hw_range_x_max - hw_range_x_min;
+        const int hw_h = hw_range_y_max - hw_range_y_min;
+        tp.normalPosition = QPointF(hw_x / qreal(hw_w),
+                                    hw_y / qreal(hw_h));
+
+        qreal nx = tp.normalPosition.x();
+        qreal ny = tp.normalPosition.y();
+
+        // Generate a screen position that is always inside the active window or the default screen.
+        const int wx = winRect.left() + int(nx * winRect.width());
+        const int wy = winRect.top() + int(ny * winRect.height());
+        tp.area.moveTopLeft(QPoint(wx, wy));
+
+#ifdef POINT_DEBUG
+        qDebug() << "    " << i << tp.area << tp.state << tp.id << tp.isPrimary << tp.pressure;
+#endif
+    }
+
+    QWindowSystemInterface::handleTouchEvent(0, state, QTouchEvent::TouchScreen, touchPoints);
+}
+
+QT_END_NAMESPACE

src/plugins/generic/touchscreen/qtoucheventsenderqpa.h

@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTOUCHEVENTSENDERQPA_H
+#define QTOUCHEVENTSENDERQPA_H
+
+#include "qtouchscreen.h"
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+class QTouchEventSenderQPA : public QTouchScreenObserver
+{
+public:
+    void touch_configure(int x_min, int x_max, int y_min, int y_max);
+    void touch_point(QEvent::Type state, const QList<QWindowSystemInterface::TouchPoint> &points);
+
+private:
+    int hw_range_x_min;
+    int hw_range_x_max;
+    int hw_range_y_min;
+    int hw_range_y_max;
+};
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QTOUCHEVENTSENDERQPA_H

src/plugins/generic/touchscreen/qtouchscreen.cpp

@@ -0,0 +1,324 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qtouchscreen.h"
+#include <QStringList>
+#include <QSocketNotifier>
+#include <QtCore/private/qcore_unix_p.h>
+#include <QDebug>
+
+#include <libudev.h>
+
+extern "C" {
+#include <mtdev.h>
+}
+
+//#define POINT_DEBUG
+
+QT_BEGIN_NAMESPACE
+
+class QTouchScreenData
+{
+public:
+    QTouchScreenData(QTouchScreenHandler *q_ptr);
+
+    void handle(input_event *data);
+
+    QTouchScreenHandler *q;
+    QEvent::Type m_state;
+    QEvent::Type m_prevState;
+    QList<QWindowSystemInterface::TouchPoint> m_touchPoints;
+
+    struct Slot {
+        int trackingId;
+        int x;
+        int y;
+        Qt::TouchPointState state;
+        bool primary;
+        Slot() : trackingId(0), x(0), y(0), state(Qt::TouchPointPressed), primary(false) { }
+    };
+    QMap<int, Slot> m_slots;
+    QMap<int, QPoint> m_lastReport;
+    int m_currentSlot;
+
+    int hw_range_x_min;
+    int hw_range_x_max;
+    int hw_range_y_min;
+    int hw_range_y_max;
+    QString hw_name;
+
+    QList<QTouchScreenObserver *> m_observers;
+};
+
+QTouchScreenData::QTouchScreenData(QTouchScreenHandler *q_ptr)
+    : q(q_ptr),
+      m_state(QEvent::TouchBegin),
+      m_prevState(m_state),
+      m_currentSlot(0),
+      hw_range_x_min(0), hw_range_x_max(0),
+      hw_range_y_min(0), hw_range_y_max(0)
+{
+}
+
+QTouchScreenHandler::QTouchScreenHandler(const QString &spec)
+    : m_notify(0), m_fd(-1), m_mtdev(0), d(0)
+{
+    setObjectName(QLatin1String("LinuxInputSubsystem Touch Handler"));
+
+    QString dev = QLatin1String("/dev/input/event5");
+    try_udev(&dev);
+
+    QStringList args = spec.split(QLatin1Char(':'));
+    for (int i = 0; i < args.count(); ++i)
+        if (args.at(i).startsWith(QLatin1String("/dev/")))
+            dev = args.at(i);
+
+    qDebug("Using device '%s'", qPrintable(dev));
+    m_fd = QT_OPEN(dev.toLocal8Bit().constData(), O_RDONLY | O_NDELAY, 0);
+
+    if (m_fd >= 0) {
+        m_notify = new QSocketNotifier(m_fd, QSocketNotifier::Read, this);
+        connect(m_notify, SIGNAL(activated(int)), this, SLOT(readData()));
+    } else {
+        qWarning("Cannot open input device '%s': %s", qPrintable(dev), strerror(errno));
+        return;
+    }
+
+    m_mtdev = (mtdev *) calloc(1, sizeof(mtdev));
+    int mtdeverr = mtdev_open(m_mtdev, m_fd);
+    if (mtdeverr) {
+        qWarning("mtdev_open failed: %d", mtdeverr);
+        QT_CLOSE(m_fd);
+        return;
+    }
+
+    d = new QTouchScreenData(this);
+
+    input_absinfo absInfo;
+    memset(&absInfo, 0, sizeof(input_absinfo));
+    if (!ioctl(m_fd, EVIOCGABS(ABS_X), &absInfo) >= 0) {
+        qDebug("min X: %d max X: %d", absInfo.minimum, absInfo.maximum);
+        d->hw_range_x_min = absInfo.minimum;
+        d->hw_range_x_max = absInfo.maximum;
+    }
+    if (!ioctl(m_fd, EVIOCGABS(ABS_Y), &absInfo) >= 0) {
+        qDebug("min Y: %d max Y: %d", absInfo.minimum, absInfo.maximum);
+        d->hw_range_y_min = absInfo.minimum;
+        d->hw_range_y_max = absInfo.maximum;
+    }
+    char name[1024];
+    if (ioctl(m_fd, EVIOCGNAME(sizeof(name) - 1), name) >= 0) {
+        d->hw_name = QString::fromUtf8(name);
+        qDebug() << "device name" << d->hw_name;
+    }
+}
+
+QTouchScreenHandler::~QTouchScreenHandler()
+{
+    if (m_fd >= 0)
+        QT_CLOSE(m_fd);
+
+    if (m_mtdev) {
+        mtdev_close(m_mtdev);
+        free(m_mtdev);
+    }
+
+    delete d;
+}
+
+void QTouchScreenHandler::addObserver(QTouchScreenObserver *observer)
+{
+    if (!d || !observer)
+        return;
+    d->m_observers.append(observer);
+    observer->touch_configure(d->hw_range_x_min, d->hw_range_x_max,
+                              d->hw_range_y_min, d->hw_range_y_max);
+}
+
+void QTouchScreenHandler::try_udev(QString *path)
+{
+    udev *u = udev_new();
+    udev_enumerate *ue = udev_enumerate_new(u);
+    udev_enumerate_add_match_subsystem(ue, "input");
+    udev_enumerate_add_match_property(ue, "QT_TOUCH", "1");
+    udev_enumerate_scan_devices(ue);
+    udev_list_entry *entry;
+    udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(ue)) {
+        const char *syspath = udev_list_entry_get_name(entry);
+        udev_device *udevice = udev_device_new_from_syspath(u, syspath);
+        *path = QString::fromLocal8Bit(udev_device_get_devnode(udevice));
+        qDebug("from udev: %s", qPrintable(*path));
+        udev_device_unref(udevice);
+    }
+    udev_enumerate_unref(ue);
+    udev_unref(u);
+}
+
+void QTouchScreenHandler::readData()
+{
+    input_event buffer[32];
+    int n = 0;
+    n = mtdev_get(m_mtdev, m_fd, buffer, sizeof(buffer) / sizeof(input_event));
+    if (n < 0) {
+        if (errno != EINTR && errno != EAGAIN)
+            qWarning("Could not read from input device: %s", strerror(errno));
+    } else if (n > 0) {
+        for (int i = 0; i < n; ++i) {
+            input_event *data = &buffer[i];
+            d->handle(data);
+        }
+    }
+}
+
+void QTouchScreenData::handle(input_event *data)
+{
+    if (data->type == EV_ABS) {
+         if (data->code == ABS_MT_POSITION_X) {
+             m_slots[m_currentSlot].x = data->value;
+         } else if (data->code == ABS_MT_POSITION_Y) {
+             m_slots[m_currentSlot].y = data->value;
+         } else if (data->code == ABS_MT_SLOT) {
+             m_currentSlot = data->value;
+         } else if (data->code == ABS_MT_TRACKING_ID) {
+             if (data->value == -1) {
+                 bool wasPrimary = m_slots[m_currentSlot].primary;
+                 m_lastReport.remove(m_slots[m_currentSlot].trackingId);
+                 m_slots.remove(m_currentSlot);
+                 if (wasPrimary && !m_slots.isEmpty())
+                     m_slots[m_slots.keys().at(0)].primary = true;
+             } else {
+                m_slots[m_currentSlot].trackingId = data->value;
+                m_slots[m_currentSlot].primary = m_slots.count() == 1;
+             }
+         } else if (data->code == ABS_MT_TOUCH_MAJOR) {
+             if (data->value == 0)
+                 m_slots[m_currentSlot].state = Qt::TouchPointReleased;
+         }
+    } else if (data->type == EV_SYN && data->code == SYN_REPORT) {
+        m_touchPoints.clear();
+        QList<int> keys = m_slots.keys();
+        int ignoredSlotCount = 0;
+        for (int i = 0; i < keys.count(); ++i) {
+            const Slot &slot(m_slots.value(keys.at(i)));
+            if (slot.trackingId == 0) {
+                ++ignoredSlotCount;
+                continue;
+            }
+            QWindowSystemInterface::TouchPoint tp;
+            tp.id = slot.trackingId;
+            tp.isPrimary = slot.primary;
+            tp.pressure = slot.state == Qt::TouchPointReleased ? 0 : 1;
+            tp.area = QRectF(slot.x, slot.y, 1, 1);
+            tp.state = slot.state;
+            if (slot.state == Qt::TouchPointMoved && m_lastReport.contains(slot.trackingId)) {
+                QPoint lastPos = m_lastReport.value(slot.trackingId);
+                if (lastPos.x() == slot.x && lastPos.y() == slot.y)
+                    tp.state = Qt::TouchPointStationary;
+            }
+            m_touchPoints.append(tp);
+            m_lastReport.insert(slot.trackingId, QPoint(slot.x, slot.y));
+        }
+        if (m_slots.count() - ignoredSlotCount == 0)
+            m_state = QEvent::TouchEnd;
+
+        // Skip if state is TouchUpdate and all points are Stationary.
+        bool skip = false;
+        if (m_state == QEvent::TouchUpdate) {
+            skip = true;
+            for (int i = 0; i < m_touchPoints.count(); ++i)
+                if (m_touchPoints.at(i).state != Qt::TouchPointStationary) {
+                    skip = false;
+                    break;
+                }
+        }
+
+        // ### TODO Add timestamps and remove points that stay unchanged for too long.
+        // The user's finger may fall off the touchscreen, which means there will be
+        // no released event sent ever for that particular point.
+
+#ifdef POINT_DEBUG
+        qDebug() << m_touchPoints.count() << "touchpoints, event type" << m_state;
+        for (int i = 0; i < m_touchPoints.count(); ++i)
+            qDebug() << "    " << m_touchPoints[i].id << m_touchPoints[i].state << m_touchPoints[i].area;
+#endif
+
+        if (!skip && !(m_state == m_prevState && m_state == QEvent::TouchEnd))
+            for (int i = 0; i < m_observers.count(); ++i)
+                m_observers.at(i)->touch_point(m_state, m_touchPoints);
+
+        for (int i = 0; i < keys.count(); ++i) {
+            Slot &slot(m_slots[keys.at(i)]);
+            if (slot.state == Qt::TouchPointPressed)
+                slot.state = Qt::TouchPointMoved;
+        }
+        m_prevState = m_state;
+        if (m_state == QEvent::TouchBegin)
+            m_state = QEvent::TouchUpdate;
+        else if (m_state == QEvent::TouchEnd)
+            m_state = QEvent::TouchBegin;
+    }
+}
+
+
+QTouchScreenHandlerThread::QTouchScreenHandlerThread(const QString &spec,
+                                                     QTouchScreenObserver *observer)
+    : m_spec(spec), m_handler(0), m_observer(observer)
+{
+    start();
+}
+
+QTouchScreenHandlerThread::~QTouchScreenHandlerThread()
+{
+    quit();
+    wait();
+}
+
+void QTouchScreenHandlerThread::run()
+{
+    m_handler = new QTouchScreenHandler(m_spec);
+    m_handler->addObserver(m_observer);
+    exec();
+    delete m_handler;
+    m_handler = 0;
+}
+
+
+QT_END_NAMESPACE

src/plugins/generic/touchscreen/qtouchscreen.h

@@ -0,0 +1,106 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the plugins module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTOUCHSCREEN_H
+#define QTOUCHSCREEN_H
+
+#include <QObject>
+#include <QString>
+#include <QList>
+#include <QThread>
+#include <QtGui/private/qwindowsysteminterface_qpa_p.h>
+
+QT_BEGIN_HEADER
+
+struct mtdev;
+
+QT_BEGIN_NAMESPACE
+
+class QSocketNotifier;
+class QTouchScreenData;
+
+class QTouchScreenObserver
+{
+public:
+    virtual void touch_configure(int x_min, int x_max, int y_min, int y_max) = 0;
+    virtual void touch_point(QEvent::Type state, const QList<QWindowSystemInterface::TouchPoint> &points) = 0;
+};
+
+class QTouchScreenHandler : public QObject
+{
+    Q_OBJECT
+
+public:
+    QTouchScreenHandler(const QString &spec = QString());
+    ~QTouchScreenHandler();
+    void addObserver(QTouchScreenObserver *observer);
+
+private slots:
+    void readData();
+
+private:
+    void try_udev(QString *path);
+
+    QSocketNotifier *m_notify;
+    int m_fd;
+    mtdev *m_mtdev;
+    QTouchScreenData *d;
+};
+
+class QTouchScreenHandlerThread : public QThread
+{
+public:
+    QTouchScreenHandlerThread(const QString &spec, QTouchScreenObserver *observer);
+    ~QTouchScreenHandlerThread();
+    void run();
+    QTouchScreenHandler *handler() { return m_handler; }
+
+private:
+    QString m_spec;
+    QTouchScreenHandler *m_handler;
+    QTouchScreenObserver *m_observer;
+};
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QTOUCHSCREEN_H

src/plugins/generic/touchscreen/touchscreen.pro

@@ -0,0 +1,18 @@
+TARGET = qtouchscreenplugin
+load(qt_plugin)
+
+DESTDIR = $$QT.gui.plugins/generic
+target.path = $$[QT_INSTALL_PLUGINS]/generic
+INSTALLS += target
+
+HEADERS = \
+    qtouchscreen.h \
+    qtoucheventsenderqpa.h
+
+SOURCES = main.cpp \
+    qtouchscreen.cpp \
+    qtoucheventsenderqpa.cpp
+
+QT += core-private gui-private
+
+LIBS += -ludev -lmtdev