eglfs: Support dynamic mouse cursor show/hide with DRM HW cursor

Task-number: QTBUG-52743
Change-Id: I0bea1451dfe7b049c129b11716d593115e3d8374
Reviewed-by: Louai Al-Khanji <louai.al-khanji@qt.io>

2 files changed, 81 insertions, 8 deletions

diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.cpp b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.cpp
index 97ea3f1eca..830e270eeb 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.cpp
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.cpp
@@ -1,7 +1,7 @@
 /****************************************************************************
 **
 ** Copyright (C) 2015 Pier Luigi Fiorini <pierluigi.fiorini@gmail.com>
-** Copyright (C) 2015 The Qt Company Ltd.
+** Copyright (C) 2016 The Qt Company Ltd.
 ** Contact: http://www.qt.io/licensing/
 **
 ** This file is part of the plugins of the Qt Toolkit.
@@ -41,6 +41,7 @@
 #include <QtCore/QJsonArray>
 #include <QtCore/QLoggingCategory>
 #include <QtGui/QPainter>
+#include <QtGui/private/qguiapplication_p.h>
 
 #include <xf86drm.h>
 #include <xf86drmMode.h>
@@ -62,13 +63,13 @@ QEglFSKmsCursor::QEglFSKmsCursor(QEglFSKmsScreen *screen)
     , m_cursorSize(64, 64) // 64x64 is the old standard size, we now try to query the real size below
     , m_bo(Q_NULLPTR)
     , m_cursorImage(0, 0, 0, 0, 0, 0)
-    , m_visible(true)
+    , m_state(CursorPendingVisible)
 {
     QByteArray hideCursorVal = qgetenv("QT_QPA_EGLFS_HIDECURSOR");
-    if (!hideCursorVal.isEmpty())
-        m_visible = hideCursorVal.toInt() == 0;
-    if (!m_visible)
+    if (!hideCursorVal.isEmpty() && hideCursorVal.toInt()) {
+        m_state = CursorDisabled;
         return;
+    }
 
     uint64_t width, height;
     if ((drmGetCap(m_screen->device()->fd(), DRM_CAP_CURSOR_WIDTH, &width) == 0)
@@ -85,6 +86,12 @@ QEglFSKmsCursor::QEglFSKmsCursor(QEglFSKmsScreen *screen)
         initCursorAtlas();
     }
 
+    m_deviceListener = new QEglFSKmsCursorDeviceListener(this);
+    connect(QGuiApplicationPrivate::inputDeviceManager(), &QInputDeviceManager::deviceListChanged,
+            m_deviceListener, &QEglFSKmsCursorDeviceListener::onDeviceListChanged);
+    if (!m_deviceListener->hasMouse())
+        m_state = CursorPendingHidden;
+
 #ifndef QT_NO_CURSOR
     QCursor cursor(Qt::ArrowCursor);
     changeCursor(&cursor, 0);
@@ -94,6 +101,8 @@ QEglFSKmsCursor::QEglFSKmsCursor(QEglFSKmsScreen *screen)
 
 QEglFSKmsCursor::~QEglFSKmsCursor()
 {
+    delete m_deviceListener;
+
     Q_FOREACH (QPlatformScreen *screen, m_screen->virtualSiblings()) {
         QEglFSKmsScreen *kmsScreen = static_cast<QEglFSKmsScreen *>(screen);
         drmModeSetCursor(kmsScreen->device()->fd(), kmsScreen->output().crtc_id, 0, 0, 0);
@@ -106,6 +115,31 @@ QEglFSKmsCursor::~QEglFSKmsCursor()
     }
 }
 
+void QEglFSKmsCursor::updateMouseStatus()
+{
+    const bool wasVisible = m_state == CursorVisible;
+    const bool visible = m_deviceListener->hasMouse();
+    if (visible == wasVisible)
+        return;
+
+    m_state = visible ? CursorPendingVisible : CursorPendingHidden;
+
+#ifndef QT_NO_CURSOR
+    changeCursor(nullptr, m_screen->topLevelAt(pos()));
+#endif
+}
+
+bool QEglFSKmsCursorDeviceListener::hasMouse() const
+{
+    return QGuiApplicationPrivate::inputDeviceManager()->deviceCount(QInputDeviceManager::DeviceTypePointer) > 0;
+}
+
+void QEglFSKmsCursorDeviceListener::onDeviceListChanged(QInputDeviceManager::DeviceType type)
+{
+  if (type == QInputDeviceManager::DeviceTypePointer)
+        m_cursor->updateMouseStatus();
+}
+
 void QEglFSKmsCursor::pointerEvent(const QMouseEvent &event)
 {
     setPos(event.screenPos().toPoint());
@@ -119,7 +153,15 @@ void QEglFSKmsCursor::changeCursor(QCursor *windowCursor, QWindow *window)
     if (!m_bo)
         return;
 
-    if (!m_visible)
+    if (m_state == CursorPendingHidden) {
+        m_state = CursorHidden;
+        Q_FOREACH (QPlatformScreen *screen, m_screen->virtualSiblings()) {
+            QEglFSKmsScreen *kmsScreen = static_cast<QEglFSKmsScreen *>(screen);
+            drmModeSetCursor(kmsScreen->device()->fd(), kmsScreen->output().crtc_id, 0, 0, 0);
+        }
+    }
+
+    if (m_state == CursorHidden || m_state == CursorDisabled)
         return;
 
     const Qt::CursorShape newShape = windowCursor ? windowCursor->shape() : Qt::ArrowCursor;
@@ -159,6 +201,9 @@ void QEglFSKmsCursor::changeCursor(QCursor *windowCursor, QWindow *window)
 
     uint32_t handle = gbm_bo_get_handle(m_bo).u32;
 
+    if (m_state == CursorPendingVisible)
+        m_state = CursorVisible;
+
     Q_FOREACH (QPlatformScreen *screen, m_screen->virtualSiblings()) {
         QEglFSKmsScreen *kmsScreen = static_cast<QEglFSKmsScreen *>(screen);
 
@@ -206,7 +251,7 @@ void QEglFSKmsCursor::initCursorAtlas()
             drmModeSetCursor(kmsScreen->device()->fd(), kmsScreen->output().crtc_id, 0, 0, 0);
             drmModeMoveCursor(kmsScreen->device()->fd(), kmsScreen->output().crtc_id, 0, 0);
         }
-        m_visible = false;
+        m_state = CursorDisabled;
         return;
     }
 
diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.h b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.h
index 68bc72a03f..f26df91be5 100644
--- a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.h
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms/qeglfskmscursor.h
@@ -37,12 +37,29 @@
 #include <qpa/qplatformcursor.h>
 #include <QtCore/QList>
 #include <QtGui/QImage>
+#include <QtGui/private/qinputdevicemanager_p.h>
 
 #include <gbm.h>
 
 QT_BEGIN_NAMESPACE
 
 class QEglFSKmsScreen;
+class QEglFSKmsCursor;
+
+class QEglFSKmsCursorDeviceListener : public QObject
+{
+    Q_OBJECT
+
+public:
+    QEglFSKmsCursorDeviceListener(QEglFSKmsCursor *cursor) : m_cursor(cursor) { }
+    bool hasMouse() const;
+
+public slots:
+    void onDeviceListChanged(QInputDeviceManager::DeviceType type);
+
+private:
+    QEglFSKmsCursor *m_cursor;
+};
 
 class QEglFSKmsCursor : public QPlatformCursor
 {
@@ -60,15 +77,26 @@ public:
     QPoint pos() const Q_DECL_OVERRIDE;
     void setPos(const QPoint &pos) Q_DECL_OVERRIDE;
 
+    void updateMouseStatus();
+
 private:
     void initCursorAtlas();
 
+    enum CursorState {
+        CursorDisabled,
+        CursorPendingHidden,
+        CursorHidden,
+        CursorPendingVisible,
+        CursorVisible
+    };
+
     QEglFSKmsScreen *m_screen;
     QSize m_cursorSize;
     gbm_bo *m_bo;
     QPoint m_pos;
     QPlatformCursorImage m_cursorImage;
-    bool m_visible;
+    CursorState m_state;
+    QEglFSKmsCursorDeviceListener *m_deviceListener;
 
     // cursor atlas information
     struct CursorAtlas {