diff --git a/libs/ui/SurfaceFlingerSynchro.cpp b/libs/ui/SurfaceFlingerSynchro.cpp
new file mode 100644
index 0000000..5cd9755
--- /dev/null
+++ b/libs/ui/SurfaceFlingerSynchro.cpp
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "SurfaceFlingerSynchro"
+
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <limits.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <utils/IPCThreadState.h>
+#include <utils/Log.h>
+
+#include <private/ui/SurfaceFlingerSynchro.h>
+
+namespace android {
+
+// ---------------------------------------------------------------------------
+
+SurfaceFlingerSynchro::Barrier::Barrier()
+    : state(CLOSED) { 
+}
+
+SurfaceFlingerSynchro::Barrier::~Barrier() { 
+}
+
+void SurfaceFlingerSynchro::Barrier::open() {
+    asm volatile ("":::"memory");
+    Mutex::Autolock _l(lock);
+    state = OPENED;
+    cv.broadcast();
+}
+
+void SurfaceFlingerSynchro::Barrier::close() {
+    Mutex::Autolock _l(lock);
+    state = CLOSED;
+}
+
+void SurfaceFlingerSynchro::Barrier::waitAndClose() 
+{
+    Mutex::Autolock _l(lock);
+    while (state == CLOSED) {
+        // we're about to wait, flush the binder command buffer
+        IPCThreadState::self()->flushCommands();
+        cv.wait(lock);
+    }
+    state = CLOSED;
+}
+
+status_t SurfaceFlingerSynchro::Barrier::waitAndClose(nsecs_t timeout) 
+{
+    Mutex::Autolock _l(lock);
+    while (state == CLOSED) {
+        // we're about to wait, flush the binder command buffer
+        IPCThreadState::self()->flushCommands();
+        int err = cv.waitRelative(lock, timeout);
+        if (err != 0)
+            return err;
+    }
+    state = CLOSED;
+    return NO_ERROR;
+}
+
+// ---------------------------------------------------------------------------
+
+SurfaceFlingerSynchro::SurfaceFlingerSynchro(const sp<ISurfaceComposer>& flinger)
+    : mSurfaceComposer(flinger)
+{
+}
+
+SurfaceFlingerSynchro::SurfaceFlingerSynchro()
+{
+}
+
+SurfaceFlingerSynchro::~SurfaceFlingerSynchro()
+{
+}
+
+status_t SurfaceFlingerSynchro::signal()
+{
+    mSurfaceComposer->signal();
+    return NO_ERROR;
+}
+
+status_t SurfaceFlingerSynchro::wait()
+{
+    mBarrier.waitAndClose();
+    return NO_ERROR;
+}
+
+status_t SurfaceFlingerSynchro::wait(nsecs_t timeout)
+{
+    if (timeout == 0)
+        return SurfaceFlingerSynchro::wait();
+    return mBarrier.waitAndClose(timeout);
+}
+
+void SurfaceFlingerSynchro::open()
+{
+    mBarrier.open();
+}
+
+// ---------------------------------------------------------------------------
+
+}; // namespace android
+