1 files changed, 218 insertions, 0 deletions
diff --git a/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmseventreader.cpp b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmseventreader.cpp
new file mode 100644
index 0000000000..645a0ae2e9
--- /dev/null
+++ b/src/plugins/platforms/eglfs/deviceintegration/eglfs_kms_support/qeglfskmseventreader.cpp
@@ -0,0 +1,218 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qeglfskmseventreader.h"
+#include "qeglfskmsdevice.h"
+#include <QSocketNotifier>
+#include <QCoreApplication>
+#include <QLoggingCategory>
+
+QT_BEGIN_NAMESPACE
+
+Q_DECLARE_LOGGING_CATEGORY(qLcEglfsKmsDebug)
+
+static void pageFlipHandler(int fd, unsigned int sequence, unsigned int tv_sec, unsigned int tv_usec, void *user_data)
+{
+    Q_UNUSED(fd);
+    Q_UNUSED(sequence);
+    Q_UNUSED(tv_sec);
+    Q_UNUSED(tv_usec);
+
+    QEglFSKmsEventReaderThread *t = static_cast<QEglFSKmsEventReaderThread *>(QThread::currentThread());
+    t->eventHost()->handlePageFlipCompleted(user_data);
+}
+
+class RegisterWaitFlipEvent : public QEvent
+{
+public:
+    static const QEvent::Type TYPE = QEvent::Type(QEvent::User + 1);
+    RegisterWaitFlipEvent(void *key, QMutex *mutex, QWaitCondition *cond)
+        : QEvent(TYPE), key(key), mutex(mutex), cond(cond)
+    { }
+    void *key;
+    QMutex *mutex;
+    QWaitCondition *cond;
+};
+
+bool QEglFSKmsEventHost::event(QEvent *event)
+{
+    if (event->type() == RegisterWaitFlipEvent::TYPE) {
+        RegisterWaitFlipEvent *e = static_cast<RegisterWaitFlipEvent *>(event);
+        PendingFlipWait *p = &pendingFlipWaits[0];
+        PendingFlipWait *end = p + MAX_FLIPS;
+        while (p < end) {
+            if (!p->key) {
+                p->key = e->key;
+                p->mutex = e->mutex;
+                p->cond = e->cond;
+                updateStatus();
+                return true;
+            }
+            ++p;
+        }
+        qWarning("Cannot queue page flip wait (more than %d screens?)", MAX_FLIPS);
+        e->mutex->lock();
+        e->cond->wakeOne();
+        e->mutex->unlock();
+        return true;
+    }
+    return QObject::event(event);
+}
+
+void QEglFSKmsEventHost::updateStatus()
+{
+    void **begin = &completedFlips[0];
+    void **end = begin + MAX_FLIPS;
+
+    for (int i = 0; i < MAX_FLIPS; ++i) {
+        PendingFlipWait *w = pendingFlipWaits + i;
+        if (!w->key)
+            continue;
+
+        void **p = begin;
+        while (p < end) {
+            if (*p == w->key) {
+                *p = nullptr;
+                w->key = nullptr;
+                w->mutex->lock();
+                w->cond->wakeOne();
+                w->mutex->unlock();
+                return;
+            }
+            ++p;
+        }
+    }
+}
+
+void QEglFSKmsEventHost::handlePageFlipCompleted(void *key)
+{
+    void **begin = &completedFlips[0];
+    void **end = begin + MAX_FLIPS;
+    void **p = begin;
+    while (p < end) {
+        if (*p == key) {
+            updateStatus();
+            return;
+        }
+        ++p;
+    }
+    p = begin;
+    while (p < end) {
+        if (!*p) {
+            *p = key;
+            updateStatus();
+            return;
+        }
+        ++p;
+    }
+    qWarning("Cannot store page flip status (more than %d screens?)", MAX_FLIPS);
+}
+
+void QEglFSKmsEventReaderThread::run()
+{
+    qCDebug(qLcEglfsKmsDebug, "Event reader thread: entering event loop");
+
+    QSocketNotifier notifier(m_fd, QSocketNotifier::Read);
+    QObject::connect(&notifier, &QSocketNotifier::activated, &notifier, [this] {
+        drmEventContext drmEvent;
+        memset(&drmEvent, 0, sizeof(drmEvent));
+        drmEvent.version = 2;
+        drmEvent.vblank_handler = nullptr;
+        drmEvent.page_flip_handler = pageFlipHandler;
+        drmHandleEvent(m_fd, &drmEvent);
+    });
+
+    exec();
+
+    m_ev.moveToThread(thread()); // move back to the thread where m_ev was created
+
+    qCDebug(qLcEglfsKmsDebug, "Event reader thread: event loop stopped");
+}
+
+QEglFSKmsEventReader::~QEglFSKmsEventReader()
+{
+    destroy();
+}
+
+void QEglFSKmsEventReader::create(QEglFSKmsDevice *device)
+{
+    destroy();
+
+    if (!device)
+        return;
+
+    m_device = device;
+
+    qCDebug(qLcEglfsKmsDebug, "Initalizing event reader for device %p fd %d",
+            m_device, m_device->fd());
+
+    m_thread = new QEglFSKmsEventReaderThread(m_device->fd());
+    m_thread->start();
+
+    // Change thread affinity for the event host, so that postEvent()
+    // goes through the event reader thread's event loop for that object.
+    m_thread->eventHost()->moveToThread(m_thread);
+}
+
+void QEglFSKmsEventReader::destroy()
+{
+    if (!m_device)
+        return;
+
+    qCDebug(qLcEglfsKmsDebug, "Stopping event reader for device %p", m_device);
+
+    if (m_thread) {
+        m_thread->quit();
+        m_thread->wait();
+        delete m_thread;
+        m_thread = nullptr;
+    }
+
+    m_device = nullptr;
+}
+
+void QEglFSKmsEventReader::startWaitFlip(void *key, QMutex *mutex, QWaitCondition *cond)
+{
+    if (m_thread) {
+        QCoreApplication::postEvent(m_thread->eventHost(),
+                                    new RegisterWaitFlipEvent(key, mutex, cond));
+    }
+}
+
+QT_END_NAMESPACE