Unify input device hotplugging support for embedded

On embedded the mouse cursor will now appear and reappear regardless of
how the input handling code is loaded (via a generic plugin or compiled-in
to the platform plugin).

Instead of passing around QDeviceDiscovery instances that only works
when compiling-in the code into the platform plugin, introduce a new
internal central QInputDeviceManager. The single instance of this
provides a place to store any future input device related signals and
properties.

Also introduce mouse hotplugging support to linuxfb.

[ChangeLog][QtGui] The mouse cursor on Embedded Linux is now handling
hotplugging correctly with eglfs and linuxfb regardless of how the input
handling code is loaded (via a generic plugin or built in to the platform
plugin).

Change-Id: I147c1b04a193baf216598015264f2c06e1b20f84
Reviewed-by: Andy Nichols <andy.nichols@theqtcompany.com>

18 files changed, 373 insertions, 81 deletions

diff --git a/src/gui/kernel/kernel.pri b/src/gui/kernel/kernel.pri
index 6479acd3fc..41574fa0bb 100644
--- a/src/gui/kernel/kernel.pri
+++ b/src/gui/kernel/kernel.pri
@@ -74,7 +74,9 @@ HEADERS += \
         kernel/qpaintdevicewindow_p.h \
         kernel/qrasterwindow.h \
         kernel/qplatformgraphicsbuffer.h \
-        kernel/qplatformgraphicsbufferhelper.h
+        kernel/qplatformgraphicsbufferhelper.h \
+        kernel/qinputdevicemanager_p.h \
+        kernel/qinputdevicemanager_p_p.h
 
 SOURCES += \
         kernel/qgenericpluginfactory.cpp \
@@ -130,7 +132,8 @@ SOURCES += \
         kernel/qrasterwindow.cpp \
         kernel/qplatformgraphicsbuffer.cpp \
         kernel/qplatformgraphicsbufferhelper.cpp \
-        kernel/qplatformhardwarecompositor.cpp
+        kernel/qplatformhardwarecompositor.cpp \
+        kernel/qinputdevicemanager.cpp
 
 contains(QT_CONFIG, opengl)|contains(QT_CONFIG, opengles2) {
     HEADERS += \
diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index a2953259ff..23deb2c4b2 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -75,6 +75,7 @@
 #include "private/qwindow_p.h"
 #include "private/qcursor_p.h"
 #include "private/qopenglcontext_p.h"
+#include "private/qinputdevicemanager_p.h"
 
 #include "private/qdnd_p.h"
 #include <qpa/qplatformthemefactory_p.h>
@@ -164,6 +165,8 @@ static QBasicMutex applicationFontMutex;
 QFont *QGuiApplicationPrivate::app_font = 0;
 bool QGuiApplicationPrivate::obey_desktop_settings = true;
 
+QInputDeviceManager *QGuiApplicationPrivate::m_inputDeviceManager = 0;
+
 static qreal fontSmoothingGamma = 1.7;
 
 extern void qRegisterGuiVariant();
@@ -3470,6 +3473,16 @@ void QGuiApplicationPrivate::setMouseEventFlags(QMouseEvent *event, Qt::MouseEve
     event->caps |= (value & Qt::MouseEventFlagMask) << MouseFlagsShift;
 }
 
+QInputDeviceManager *QGuiApplicationPrivate::inputDeviceManager()
+{
+    Q_ASSERT(QGuiApplication::instance());
+
+    if (!m_inputDeviceManager)
+        m_inputDeviceManager = new QInputDeviceManager(QGuiApplication::instance());
+
+    return m_inputDeviceManager;
+}
+
 #include "moc_qguiapplication.cpp"
 
 QT_END_NAMESPACE
diff --git a/src/gui/kernel/qguiapplication_p.h b/src/gui/kernel/qguiapplication_p.h
index 8b444e1d34..471316d7ed 100644
--- a/src/gui/kernel/qguiapplication_p.h
+++ b/src/gui/kernel/qguiapplication_p.h
@@ -66,6 +66,7 @@ struct QDrawHelperGammaTables;
 #ifndef QT_NO_DRAGANDDROP
 class QDrag;
 #endif // QT_NO_DRAGANDDROP
+class QInputDeviceManager;
 
 class Q_GUI_EXPORT QGuiApplicationPrivate : public QCoreApplicationPrivate
 {
@@ -272,6 +273,8 @@ public:
 
     static Qt::MouseEventSource wheelEventSource(const QWheelEvent *event);
 
+    static QInputDeviceManager *inputDeviceManager();
+
     const QDrawHelperGammaTables *gammaTables();
 
     // hook reimplemented in QApplication to apply the QStyle function on the QIcon
@@ -301,6 +304,8 @@ private:
     QAtomicPointer<QDrawHelperGammaTables> m_gammaTables;
 
     bool ownGlobalShareContext;
+
+    static QInputDeviceManager *m_inputDeviceManager;
 };
 
 Q_GUI_EXPORT uint qHash(const QGuiApplicationPrivate::ActiveTouchPointsKey &k);
diff --git a/src/gui/kernel/qinputdevicemanager.cpp b/src/gui/kernel/qinputdevicemanager.cpp
new file mode 100644
index 0000000000..925a89c85b
--- /dev/null
+++ b/src/gui/kernel/qinputdevicemanager.cpp
@@ -0,0 +1,64 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qinputdevicemanager_p.h"
+#include "qinputdevicemanager_p_p.h"
+
+QT_BEGIN_NAMESPACE
+
+QInputDeviceManager::QInputDeviceManager(QObject *parent)
+    : QObject(*new QInputDeviceManagerPrivate, parent)
+{
+}
+
+int QInputDeviceManager::deviceCount(DeviceType type) const
+{
+    Q_D(const QInputDeviceManager);
+    return d->deviceCount(type);
+}
+
+int QInputDeviceManagerPrivate::deviceCount(QInputDeviceManager::DeviceType type) const
+{
+    return m_deviceCount.value(type);
+}
+
+void QInputDeviceManagerPrivate::setDeviceCount(QInputDeviceManager::DeviceType type, int count)
+{
+    Q_Q(QInputDeviceManager);
+    if (m_deviceCount.value(type) != count) {
+        m_deviceCount[type] = count;
+        emit q->deviceListChanged(type);
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/gui/kernel/qinputdevicemanager_p.h b/src/gui/kernel/qinputdevicemanager_p.h
new file mode 100644
index 0000000000..ca334e4645
--- /dev/null
+++ b/src/gui/kernel/qinputdevicemanager_p.h
@@ -0,0 +1,77 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QINPUTDEVICEMANAGER_P_H
+#define QINPUTDEVICEMANAGER_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qobject.h>
+
+QT_BEGIN_NAMESPACE
+
+class QInputDeviceManagerPrivate;
+
+class Q_GUI_EXPORT QInputDeviceManager : public QObject
+{
+    Q_OBJECT
+    Q_DECLARE_PRIVATE(QInputDeviceManager)
+
+public:
+    enum DeviceType {
+        DeviceTypeUnknown,
+        DeviceTypePointer,
+        DeviceTypeKeyboard,
+        DeviceTypeTouch
+    };
+
+    QInputDeviceManager(QObject *parent = 0);
+
+    int deviceCount(DeviceType type) const;
+
+signals:
+    void deviceListChanged(DeviceType type);
+};
+
+QT_END_NAMESPACE
+
+#endif // QINPUTDEVICEMANAGER_P_H
diff --git a/src/gui/kernel/qinputdevicemanager_p_p.h b/src/gui/kernel/qinputdevicemanager_p_p.h
new file mode 100644
index 0000000000..7583fbe030
--- /dev/null
+++ b/src/gui/kernel/qinputdevicemanager_p_p.h
@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QINPUTDEVICEMANAGER_P_P_H
+#define QINPUTDEVICEMANAGER_P_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qmap.h>
+#include <private/qobject_p.h>
+#include "qinputdevicemanager_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class Q_GUI_EXPORT QInputDeviceManagerPrivate : public QObjectPrivate
+{
+    Q_DECLARE_PUBLIC(QInputDeviceManager)
+
+public:
+    static QInputDeviceManagerPrivate *get(QInputDeviceManager *mgr) { return mgr->d_func(); }
+
+    int deviceCount(QInputDeviceManager::DeviceType type) const;
+    void setDeviceCount(QInputDeviceManager::DeviceType type, int count);
+
+    QMap<QInputDeviceManager::DeviceType, int> m_deviceCount;
+};
+
+QT_END_NAMESPACE
+
+#endif // QINPUTDEVICEMANAGER_P_P_H
diff --git a/src/platformsupport/eglconvenience/qeglplatformcursor.cpp b/src/platformsupport/eglconvenience/qeglplatformcursor.cpp
index cf41bd2f1b..b07f8cd470 100644
--- a/src/platformsupport/eglconvenience/qeglplatformcursor.cpp
+++ b/src/platformsupport/eglconvenience/qeglplatformcursor.cpp
@@ -39,7 +39,7 @@
 #include <QtCore/QJsonObject>
 #include <QtDebug>
 
-#include <QtPlatformSupport/private/qdevicediscovery_p.h>
+#include <QtGui/private/qguiapplication_p.h>
 
 #include "qeglplatformcursor_p.h"
 #include "qeglplatformintegration_p.h"
@@ -79,6 +79,11 @@ QEGLPlatformCursor::QEGLPlatformCursor(QPlatformScreen *screen)
     QCursor cursor(Qt::ArrowCursor);
     setCurrentCursor(&cursor);
 #endif
+
+    m_deviceListener = new QEGLPlatformCursorDeviceListener(this);
+    connect(QGuiApplicationPrivate::inputDeviceManager(), &QInputDeviceManager::deviceListChanged,
+            m_deviceListener, &QEGLPlatformCursorDeviceListener::onDeviceListChanged);
+    updateMouseStatus();
 }
 
 QEGLPlatformCursor::~QEGLPlatformCursor()
@@ -87,42 +92,20 @@ QEGLPlatformCursor::~QEGLPlatformCursor()
     delete m_deviceListener;
 }
 
-void QEGLPlatformCursor::setMouseDeviceDiscovery(QDeviceDiscovery *dd)
-{
-    if (m_visible && dd) {
-        m_deviceListener = new QEGLPlatformCursorDeviceListener(dd, this);
-        updateMouseStatus();
-    }
-}
-
 void QEGLPlatformCursor::updateMouseStatus()
 {
     m_visible = m_deviceListener->hasMouse();
 }
 
-QEGLPlatformCursorDeviceListener::QEGLPlatformCursorDeviceListener(QDeviceDiscovery *dd, QEGLPlatformCursor *cursor)
-    : m_cursor(cursor)
-{
-    m_mouseCount = dd->scanConnectedDevices().count();
-    connect(dd, SIGNAL(deviceDetected(QString)), SLOT(onDeviceAdded()));
-    connect(dd, SIGNAL(deviceRemoved(QString)), SLOT(onDeviceRemoved()));
-}
-
 bool QEGLPlatformCursorDeviceListener::hasMouse() const
 {
-    return m_mouseCount > 0;
-}
-
-void QEGLPlatformCursorDeviceListener::onDeviceAdded()
-{
-    ++m_mouseCount;
-    m_cursor->updateMouseStatus();
+    return QGuiApplicationPrivate::inputDeviceManager()->deviceCount(QInputDeviceManager::DeviceTypePointer) > 0;
 }
 
-void QEGLPlatformCursorDeviceListener::onDeviceRemoved()
+void QEGLPlatformCursorDeviceListener::onDeviceListChanged(QInputDeviceManager::DeviceType type)
 {
-    --m_mouseCount;
-    m_cursor->updateMouseStatus();
+    if (type == QInputDeviceManager::DeviceTypePointer)
+        m_cursor->updateMouseStatus();
 }
 
 void QEGLPlatformCursor::resetResources()
diff --git a/src/platformsupport/eglconvenience/qeglplatformcursor_p.h b/src/platformsupport/eglconvenience/qeglplatformcursor_p.h
index bf2aeef378..8d111e26ed 100644
--- a/src/platformsupport/eglconvenience/qeglplatformcursor_p.h
+++ b/src/platformsupport/eglconvenience/qeglplatformcursor_p.h
@@ -48,11 +48,11 @@
 #include <qpa/qplatformcursor.h>
 #include <qpa/qplatformscreen.h>
 #include <QtGui/QOpenGLFunctions>
+#include <QtGui/private/qinputdevicemanager_p.h>
 
 QT_BEGIN_NAMESPACE
 
 class QOpenGLShaderProgram;
-class QDeviceDiscovery;
 class QEGLPlatformCursor;
 
 class QEGLPlatformCursorDeviceListener : public QObject
@@ -60,16 +60,14 @@ class QEGLPlatformCursorDeviceListener : public QObject
     Q_OBJECT
 
 public:
-    QEGLPlatformCursorDeviceListener(QDeviceDiscovery *dd, QEGLPlatformCursor *cursor);
+    QEGLPlatformCursorDeviceListener(QEGLPlatformCursor *cursor) : m_cursor(cursor) { }
     bool hasMouse() const;
 
-private slots:
-    void onDeviceAdded();
-    void onDeviceRemoved();
+public slots:
+    void onDeviceListChanged(QInputDeviceManager::DeviceType type);
 
 private:
     QEGLPlatformCursor *m_cursor;
-    int m_mouseCount;
 };
 
 class QEGLPlatformCursorUpdater : public QObject
@@ -108,7 +106,6 @@ public:
     void paintOnScreen();
     void resetResources();
 
-    void setMouseDeviceDiscovery(QDeviceDiscovery *dd);
     void updateMouseStatus();
 
 private:
diff --git a/src/platformsupport/eglconvenience/qeglplatformintegration.cpp b/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
index e2a215d35f..ef794f0e1b 100644
--- a/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
+++ b/src/platformsupport/eglconvenience/qeglplatformintegration.cpp
@@ -352,12 +352,7 @@ void QEGLPlatformIntegration::createInputHandlers()
 {
 #if !defined(QT_NO_EVDEV) && (!defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK))
     m_kbdMgr = new QEvdevKeyboardManager(QLatin1String("EvdevKeyboard"), QString() /* spec */, this);
-    QEvdevMouseManager *mouseMgr = new QEvdevMouseManager(QLatin1String("EvdevMouse"), QString() /* spec */, this);
-    Q_FOREACH (QScreen *screen, QGuiApplication::screens()) {
-        QEGLPlatformCursor *cursor = qobject_cast<QEGLPlatformCursor *>(screen->handle()->cursor());
-        if (cursor)
-            cursor->setMouseDeviceDiscovery(mouseMgr->deviceDiscovery());
-    }
+    new QEvdevMouseManager(QLatin1String("EvdevMouse"), QString() /* spec */, this);
 #ifndef QT_NO_TSLIB
     const bool useTslib = qEnvironmentVariableIntValue("QT_QPA_EGLFS_TSLIB");
     if (useTslib)
diff --git a/src/platformsupport/fbconvenience/qfbcursor.cpp b/src/platformsupport/fbconvenience/qfbcursor.cpp
index 806556b1e4..8d6a695d68 100644
--- a/src/platformsupport/fbconvenience/qfbcursor.cpp
+++ b/src/platformsupport/fbconvenience/qfbcursor.cpp
@@ -34,14 +34,47 @@
 #include "qfbcursor_p.h"
 #include "qfbscreen_p.h"
 #include <QtGui/QPainter>
+#include <QtGui/private/qguiapplication_p.h>
 
 QT_BEGIN_NAMESPACE
 
+bool QFbCursorDeviceListener::hasMouse() const
+{
+    return QGuiApplicationPrivate::inputDeviceManager()->deviceCount(QInputDeviceManager::DeviceTypePointer) > 0;
+}
+
+void QFbCursorDeviceListener::onDeviceListChanged(QInputDeviceManager::DeviceType type)
+{
+    if (type == QInputDeviceManager::DeviceTypePointer)
+        m_cursor->updateMouseStatus();
+}
+
 QFbCursor::QFbCursor(QFbScreen *screen)
-        : mScreen(screen), mDirty(false), mOnScreen(false)
+    : mVisible(true),
+      mScreen(screen),
+      mDirty(false),
+      mOnScreen(false),
+      mGraphic(0),
+      mDeviceListener(0)
 {
+    QByteArray hideCursorVal = qgetenv("QT_QPA_FB_HIDECURSOR");
+    if (!hideCursorVal.isEmpty())
+        mVisible = hideCursorVal.toInt() == 0;
+    if (!mVisible)
+        return;
+
     mGraphic = new QPlatformCursorImage(0, 0, 0, 0, 0, 0);
     setCursor(Qt::ArrowCursor);
+
+    mDeviceListener = new QFbCursorDeviceListener(this);
+    connect(QGuiApplicationPrivate::inputDeviceManager(), &QInputDeviceManager::deviceListChanged,
+            mDeviceListener, &QFbCursorDeviceListener::onDeviceListChanged);
+    updateMouseStatus();
+}
+
+QFbCursor::~QFbCursor()
+{
+    delete mDeviceListener;
 }
 
 QRect QFbCursor::getCurrentRect()
@@ -68,6 +101,9 @@ void QFbCursor::pointerEvent(const QMouseEvent & e)
 
 QRect QFbCursor::drawCursor(QPainter & painter)
 {
+    if (!mVisible)
+        return QRect();
+
     mDirty = false;
     if (mCurrentRect.isNull())
         return QRect();
@@ -131,15 +167,19 @@ void QFbCursor::changeCursor(QCursor * widgetCursor, QWindow *window)
 
 void QFbCursor::setDirty()
 {
+    if (!mVisible)
+        return;
+
     if (!mDirty) {
         mDirty = true;
         mScreen->scheduleUpdate();
     }
 }
 
-void QFbCursor::setMouseDeviceDiscovery(QDeviceDiscovery *dd)
+void QFbCursor::updateMouseStatus()
 {
-    Q_UNUSED(dd);
+    mVisible = mDeviceListener->hasMouse();
+    mScreen->setDirty(mVisible ? getCurrentRect() : lastPainted());
 }
 
 QT_END_NAMESPACE
diff --git a/src/platformsupport/fbconvenience/qfbcursor_p.h b/src/platformsupport/fbconvenience/qfbcursor_p.h
index 75501a0ff0..bec781fb21 100644
--- a/src/platformsupport/fbconvenience/qfbcursor_p.h
+++ b/src/platformsupport/fbconvenience/qfbcursor_p.h
@@ -46,11 +46,27 @@
 //
 
 #include <qpa/qplatformcursor.h>
+#include <QtGui/private/qinputdevicemanager_p.h>
 
 QT_BEGIN_NAMESPACE
 
 class QFbScreen;
-class QDeviceDiscovery;
+class QFbCursor;
+
+class QFbCursorDeviceListener : public QObject
+{
+    Q_OBJECT
+
+public:
+    QFbCursorDeviceListener(QFbCursor *cursor) : m_cursor(cursor) { }
+    bool hasMouse() const;
+
+public slots:
+    void onDeviceListChanged(QInputDeviceManager::DeviceType type);
+
+private:
+    QFbCursor *m_cursor;
+};
 
 class QFbCursor : public QPlatformCursor
 {
@@ -58,6 +74,7 @@ class QFbCursor : public QPlatformCursor
 
 public:
     QFbCursor(QFbScreen *screen);
+    ~QFbCursor();
 
     // output methods
     QRect dirtyRect();
@@ -74,7 +91,7 @@ public:
     virtual bool isOnScreen() const { return mOnScreen; }
     virtual QRect lastPainted() const { return mPrevRect; }
 
-    void setMouseDeviceDiscovery(QDeviceDiscovery *dd);
+    void updateMouseStatus();
 
 private:
     void setCursor(const uchar *data, const uchar *mask, int width, int height, int hotX, int hotY);
@@ -82,12 +99,14 @@ private:
     void setCursor(const QImage &image, int hotx, int hoty);
     QRect getCurrentRect();
 
+    bool mVisible;
     QFbScreen *mScreen;
     QRect mCurrentRect;      // next place to draw the cursor
     QRect mPrevRect;         // last place the cursor was drawn
     bool mDirty;
     bool mOnScreen;
     QPlatformCursorImage *mGraphic;
+    QFbCursorDeviceListener *mDeviceListener;
 };
 
 QT_END_NAMESPACE
diff --git a/src/platformsupport/input/evdevkeyboard/qevdevkeyboardmanager.cpp b/src/platformsupport/input/evdevkeyboard/qevdevkeyboardmanager.cpp
index 4614fbd499..8853da8371 100644
--- a/src/platformsupport/input/evdevkeyboard/qevdevkeyboardmanager.cpp
+++ b/src/platformsupport/input/evdevkeyboard/qevdevkeyboardmanager.cpp
@@ -37,6 +37,9 @@
 #include <QCoreApplication>
 #include <QLoggingCategory>
 
+#include <private/qguiapplication_p.h>
+#include <private/qinputdevicemanager_p_p.h>
+
 QT_BEGIN_NAMESPACE
 
 Q_DECLARE_LOGGING_CATEGORY(qLcEvdevKey)
@@ -97,10 +100,13 @@ void QEvdevKeyboardManager::addKeyboard(const QString &deviceNode)
     qCDebug(qLcEvdevKey) << "Adding keyboard at" << deviceNode;
     QEvdevKeyboardHandler *keyboard;
     keyboard = QEvdevKeyboardHandler::create(deviceNode, m_spec, m_defaultKeymapFile);
-    if (keyboard)
+    if (keyboard) {
         m_keyboards.insert(deviceNode, keyboard);
-    else
+        QInputDeviceManagerPrivate::get(QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
+            QInputDeviceManager::DeviceTypeKeyboard, m_keyboards.count());
+    } else {
         qWarning("Failed to open keyboard device %s", qPrintable(deviceNode));
+    }
 }
 
 void QEvdevKeyboardManager::removeKeyboard(const QString &deviceNode)
@@ -109,6 +115,8 @@ void QEvdevKeyboardManager::removeKeyboard(const QString &deviceNode)
         qCDebug(qLcEvdevKey) << "Removing keyboard at" << deviceNode;
         QEvdevKeyboardHandler *keyboard = m_keyboards.value(deviceNode);
         m_keyboards.remove(deviceNode);
+        QInputDeviceManagerPrivate::get(QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
+            QInputDeviceManager::DeviceTypeKeyboard, m_keyboards.count());
         delete keyboard;
     }
 }
diff --git a/src/platformsupport/input/evdevmouse/qevdevmousemanager.cpp b/src/platformsupport/input/evdevmouse/qevdevmousemanager.cpp
index a0c9c9f34d..17e6b0cafa 100644
--- a/src/platformsupport/input/evdevmouse/qevdevmousemanager.cpp
+++ b/src/platformsupport/input/evdevmouse/qevdevmousemanager.cpp
@@ -38,6 +38,9 @@
 #include <QScreen>
 #include <QLoggingCategory>
 #include <qpa/qwindowsysteminterface.h>
+#include <QtPlatformSupport/private/qdevicediscovery_p.h>
+#include <private/qguiapplication_p.h>
+#include <private/qinputdevicemanager_p_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -141,6 +144,8 @@ void QEvdevMouseManager::addMouse(const QString &deviceNode)
         connect(handler, SIGNAL(handleMouseEvent(int,int,bool,Qt::MouseButtons)), this, SLOT(handleMouseEvent(int,int,bool,Qt::MouseButtons)));
         connect(handler, SIGNAL(handleWheelEvent(int,Qt::Orientation)), this, SLOT(handleWheelEvent(int,Qt::Orientation)));
         m_mice.insert(deviceNode, handler);
+        QInputDeviceManagerPrivate::get(QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
+            QInputDeviceManager::DeviceTypePointer, m_mice.count());
     } else {
         qWarning("evdevmouse: Failed to open mouse device %s", qPrintable(deviceNode));
     }
@@ -152,6 +157,8 @@ void QEvdevMouseManager::removeMouse(const QString &deviceNode)
         qCDebug(qLcEvdevMouse) << "Removing mouse at" << deviceNode;
         QEvdevMouseHandler *handler = m_mice.value(deviceNode);
         m_mice.remove(deviceNode);
+        QInputDeviceManagerPrivate::get(QGuiApplicationPrivate::inputDeviceManager())->setDeviceCount(
+            QInputDeviceManager::DeviceTypePointer, m_mice.count());
         delete handler;
     }
 }
diff --git a/src/platformsupport/input/evdevmouse/qevdevmousemanager_p.h b/src/platformsupport/input/evdevmouse/qevdevmousemanager_p.h
index 14aa6a8fd2..d30a2b337f 100644
--- a/src/platformsupport/input/evdevmouse/qevdevmousemanager_p.h
+++ b/src/platformsupport/input/evdevmouse/qevdevmousemanager_p.h
@@ -47,14 +47,14 @@
 
 #include "qevdevmousehandler_p.h"
 
-#include <QtPlatformSupport/private/qdevicediscovery_p.h>
-
 #include <QObject>
 #include <QHash>
 #include <QSocketNotifier>
 
 QT_BEGIN_NAMESPACE
 
+class QDeviceDiscovery;
+
 class QEvdevMouseManager : public QObject
 {
     Q_OBJECT
@@ -62,8 +62,6 @@ public:
     QEvdevMouseManager(const QString &key, const QString &specification, QObject *parent = 0);
     ~QEvdevMouseManager();
 
-    QDeviceDiscovery *deviceDiscovery() { return m_deviceDiscovery; }
-
 public slots:
     void handleMouseEvent(int x, int y, bool abs, Qt::MouseButtons buttons);
     void handleWheelEvent(int delta, Qt::Orientation orientation);
diff --git a/src/platformsupport/input/libinput/qlibinputhandler.cpp b/src/platformsupport/input/libinput/qlibinputhandler.cpp
index cab4527d0a..0ed605019c 100644
--- a/src/platformsupport/input/libinput/qlibinputhandler.cpp
+++ b/src/platformsupport/input/libinput/qlibinputhandler.cpp
@@ -41,6 +41,8 @@
 #include <QtCore/QLoggingCategory>
 #include <QtCore/QSocketNotifier>
 #include <QtCore/private/qcore_unix_p.h>
+#include <private/qguiapplication_p.h>
+#include <private/qinputdevicemanager_p_p.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -146,8 +148,25 @@ void QLibInputHandler::processEvent(libinput_event *ev)
         const char *sysname = libinput_device_get_sysname(dev); // node name without path
         const char *name = libinput_device_get_name(dev);
         emit deviceAdded(QString::fromUtf8(sysname), QString::fromUtf8(name));
-        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_TOUCH))
+
+        QInputDeviceManagerPrivate *inputManagerPriv = QInputDeviceManagerPrivate::get(
+            QGuiApplicationPrivate::inputDeviceManager());
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_TOUCH)) {
             m_touch->registerDevice(dev);
+            int &count(m_devCount[QInputDeviceManager::DeviceTypeTouch]);
+            ++count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypeTouch, count);
+        }
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_POINTER)) {
+            int &count(m_devCount[QInputDeviceManager::DeviceTypePointer]);
+            ++count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypePointer, count);
+        }
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_KEYBOARD)) {
+            int &count(m_devCount[QInputDeviceManager::DeviceTypeKeyboard]);
+            ++count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypeKeyboard, count);
+        }
         break;
     }
     case LIBINPUT_EVENT_DEVICE_REMOVED:
@@ -155,8 +174,25 @@ void QLibInputHandler::processEvent(libinput_event *ev)
         const char *sysname = libinput_device_get_sysname(dev);
         const char *name = libinput_device_get_name(dev);
         emit deviceRemoved(QString::fromUtf8(sysname), QString::fromUtf8(name));
-        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_TOUCH))
+
+        QInputDeviceManagerPrivate *inputManagerPriv = QInputDeviceManagerPrivate::get(
+            QGuiApplicationPrivate::inputDeviceManager());
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_TOUCH)) {
             m_touch->unregisterDevice(dev);
+            int &count(m_devCount[QInputDeviceManager::DeviceTypeTouch]);
+            --count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypeTouch, count);
+        }
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_POINTER)) {
+            int &count(m_devCount[QInputDeviceManager::DeviceTypePointer]);
+            --count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypePointer, count);
+        }
+        if (libinput_device_has_capability(dev, LIBINPUT_DEVICE_CAP_KEYBOARD)) {
+            int &count(m_devCount[QInputDeviceManager::DeviceTypeKeyboard]);
+            --count;
+            inputManagerPriv->setDeviceCount(QInputDeviceManager::DeviceTypeKeyboard, count);
+        }
         break;
     }
     case LIBINPUT_EVENT_POINTER_BUTTON:
diff --git a/src/platformsupport/input/libinput/qlibinputhandler_p.h b/src/platformsupport/input/libinput/qlibinputhandler_p.h
index a1cfaca3ce..6d376c4ca3 100644
--- a/src/platformsupport/input/libinput/qlibinputhandler_p.h
+++ b/src/platformsupport/input/libinput/qlibinputhandler_p.h
@@ -36,6 +36,7 @@
 
 #include <QtCore/QObject>
 #include <QtCore/QScopedPointer>
+#include <QtCore/QMap>
 
 //
 //  W A R N I N G
@@ -84,6 +85,7 @@ private:
     QScopedPointer<QLibInputPointer> m_pointer;
     QScopedPointer<QLibInputKeyboard> m_keyboard;
     QScopedPointer<QLibInputTouch> m_touch;
+    QMap<int, int> m_devCount;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/linuxfb/qlinuxfbintegration.cpp b/src/plugins/platforms/linuxfb/qlinuxfbintegration.cpp
index 1600ee3f2b..6785464cea 100644
--- a/src/plugins/platforms/linuxfb/qlinuxfbintegration.cpp
+++ b/src/plugins/platforms/linuxfb/qlinuxfbintegration.cpp
@@ -130,12 +130,7 @@ void QLinuxFbIntegration::createInputHandlers()
 {
 #if !defined(QT_NO_EVDEV) && (!defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK))
     new QEvdevKeyboardManager(QLatin1String("EvdevKeyboard"), QString(), this);
-    QEvdevMouseManager *mouseMgr = new QEvdevMouseManager(QLatin1String("EvdevMouse"), QString(), this);
-    Q_FOREACH (QScreen *screen, QGuiApplication::screens()) {
-        QFbCursor *cursor = qobject_cast<QFbCursor *>(screen->handle()->cursor());
-        if (cursor)
-            cursor->setMouseDeviceDiscovery(mouseMgr->deviceDiscovery());
-    }
+    new QEvdevMouseManager(QLatin1String("EvdevMouse"), QString(), this);
 #ifndef QT_NO_TSLIB
     const bool useTslib = qEnvironmentVariableIntValue("QT_QPA_FB_TSLIB");
     if (useTslib)
diff --git a/src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp b/src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp
index a66c9fa252..592ce90b16 100644
--- a/src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp
+++ b/src/plugins/platforms/linuxfb/qlinuxfbscreen.cpp
@@ -55,10 +55,6 @@
 
 #include <linux/fb.h>
 
-#if !defined(QT_NO_EVDEV) && (!defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK))
-#include <QtPlatformSupport/private/qdevicediscovery_p.h>
-#endif
-
 QT_BEGIN_NAMESPACE
 
 static int openFramebufferDevice(const QString &dev)
@@ -393,22 +389,7 @@ bool QLinuxFbScreen::initialize()
     QFbScreen::initializeCompositor();
     mFbScreenImage = QImage(mMmap.data, geometry.width(), geometry.height(), mBytesPerLine, mFormat);
 
-    QByteArray hideCursorVal = qgetenv("QT_QPA_FB_HIDECURSOR");
-#if !defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK)
-    bool hideCursor = false;
-#else
-    bool hideCursor = true; // default to true to prevent the cursor showing up with the subclass on Android
-#endif
-    if (hideCursorVal.isEmpty()) {
-#if !defined(QT_NO_EVDEV) && (!defined(Q_OS_ANDROID) || defined(Q_OS_ANDROID_NO_SDK))
-        QScopedPointer<QDeviceDiscovery> dis(QDeviceDiscovery::create(QDeviceDiscovery::Device_Mouse));
-        hideCursor = dis->scanConnectedDevices().isEmpty();
-#endif
-    } else {
-        hideCursor = hideCursorVal.toInt() != 0;
-    }
-    if (!hideCursor)
-        mCursor = new QFbCursor(this);
+    mCursor = new QFbCursor(this);
 
     mTtyFd = openTtyDevice(ttyDevice);
     if (mTtyFd == -1)