diff --git a/include/gui/ISurfaceTexture.h b/include/gui/ISurfaceTexture.h
index 168310c..6ed3c6f 100644
--- a/include/gui/ISurfaceTexture.h
+++ b/include/gui/ISurfaceTexture.h
@@ -62,8 +62,11 @@
     // contents of the buffer associated with slot and transfers ownership of
     // that slot back to the server. It is not valid to call queueBuffer on a
     // slot that is not owned by the client or one for which a buffer associated
-    // via requestBuffer.
-    virtual status_t queueBuffer(int slot) = 0;
+    // via requestBuffer. In addition, a timestamp must be provided by the
+    // client for this buffer. The timestamp is measured in nanoseconds, and
+    // must be monotonically increasing. Its other properties (zero point, etc)
+    // are client-dependent, and should be documented by the client.
+    virtual status_t queueBuffer(int slot, int64_t timestamp) = 0;
 
     // cancelBuffer indicates that the client does not wish to fill in the
     // buffer associated with slot and transfers ownership of the slot back to
diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h
index 9bf38f7..afa64d3 100644
--- a/include/gui/SurfaceTexture.h
+++ b/include/gui/SurfaceTexture.h
@@ -66,7 +66,12 @@
     // unmodified.
     virtual status_t dequeueBuffer(int *buf);
 
-    virtual status_t queueBuffer(int buf);
+    // queueBuffer returns a filled buffer to the SurfaceTexture. In addition, a
+    // timestamp must be provided for the buffer. The timestamp is in
+    // nanoseconds, and must be monotonically increasing. Its other semantics
+    // (zero point, etc) are client-dependent and should be documented by the
+    // client.
+    virtual status_t queueBuffer(int buf, int64_t timestamp);
     virtual void cancelBuffer(int buf);
     virtual status_t setCrop(const Rect& reg);
     virtual status_t setTransform(uint32_t transform);
@@ -98,6 +103,14 @@
     // functions.
     void getTransformMatrix(float mtx[16]);
 
+    // getTimestamp retrieves the timestamp associated with the texture image
+    // set by the most recent call to updateTexImage.
+    //
+    // The timestamp is in nanoseconds, and is monotonically increasing. Its
+    // other semantics (zero point, etc) are source-dependent and should be
+    // documented by the source.
+    int64_t getTimestamp();
+
     // setFrameAvailableListener sets the listener object that will be notified
     // when a new frame becomes available.
     void setFrameAvailableListener(const sp<FrameAvailableListener>& l);
@@ -172,6 +185,10 @@
     // gets set to mLastQueuedTransform each time updateTexImage is called.
     uint32_t mCurrentTransform;
 
+    // mCurrentTimestamp is the timestamp for the current texture. It
+    // gets set to mLastQueuedTimestamp each time updateTexImage is called.
+    int64_t mCurrentTimestamp;
+
     // mLastQueued is the buffer slot index of the most recently enqueued buffer.
     // At construction time it is initialized to INVALID_BUFFER_SLOT, and is
     // updated each time queueBuffer is called.
@@ -187,6 +204,10 @@
     // queueBuffer gets called.
     uint32_t mLastQueuedTransform;
 
+    // mLastQueuedTimestamp is the timestamp for the buffer that was most
+    // recently queued. This gets set by queueBuffer.
+    int64_t mLastQueuedTimestamp;
+
     // mNextCrop is the crop rectangle that will be used for the next buffer
     // that gets queued. It is set by calling setCrop.
     Rect mNextCrop;
diff --git a/include/gui/SurfaceTextureClient.h b/include/gui/SurfaceTextureClient.h
index 7992105..df82bf2 100644
--- a/include/gui/SurfaceTextureClient.h
+++ b/include/gui/SurfaceTextureClient.h
@@ -63,6 +63,7 @@
     int dispatchSetBufferCount(va_list args);
     int dispatchSetBuffersGeometry(va_list args);
     int dispatchSetBuffersTransform(va_list args);
+    int dispatchSetBuffersTimestamp(va_list args);
     int dispatchSetCrop(va_list args);
     int dispatchSetUsage(va_list args);
 
@@ -71,6 +72,7 @@
     int setBufferCount(int bufferCount);
     int setBuffersGeometry(int w, int h, int format);
     int setBuffersTransform(int transform);
+    int setBuffersTimestamp(int64_t timestamp);
     int setCrop(Rect const* rect);
     int setUsage(uint32_t reqUsage);
 
@@ -114,6 +116,11 @@
     // at the next deuque operation. It is initialized to 0.
     uint32_t mReqUsage;
 
+    // mTimestamp is the timestamp that will be used for the next buffer queue
+    // operation. It defaults to NATIVE_WINDOW_TIMESTAMP_AUTO, which means that
+    // a timestamp is auto-generated when queueBuffer is called.
+    int64_t mTimestamp;
+
     // mMutex is the mutex used to prevent concurrent access to the member
     // variables of SurfaceTexture objects. It must be locked whenever the
     // member variables are accessed.
diff --git a/include/surfaceflinger/Surface.h b/include/surfaceflinger/Surface.h
index 9e0b5bb..a59d9e5 100644
--- a/include/surfaceflinger/Surface.h
+++ b/include/surfaceflinger/Surface.h
@@ -226,7 +226,8 @@
     int  dispatch_set_buffer_count(va_list args);
     int  dispatch_set_buffers_geometry(va_list args);
     int  dispatch_set_buffers_transform(va_list args);
-    
+    int  dispatch_set_buffers_timestamp(va_list args);
+
     void setUsage(uint32_t reqUsage);
     int  connect(int api);
     int  disconnect(int api);
@@ -234,6 +235,7 @@
     int  setBufferCount(int bufferCount);
     int  setBuffersGeometry(int w, int h, int format);
     int  setBuffersTransform(int transform);
+    int  setBuffersTimestamp(int64_t timestamp);
 
     /*
      *  private stuff...
diff --git a/include/ui/egl/android_natives.h b/include/ui/egl/android_natives.h
index 0fc1ddf..0a6e4fb 100644
--- a/include/ui/egl/android_natives.h
+++ b/include/ui/egl/android_natives.h
@@ -57,7 +57,7 @@
 {
     /* a magic value defined by the actual EGL native type */
     int magic;
-    
+
     /* the sizeof() of the actual EGL native type */
     int version;
 
@@ -129,6 +129,7 @@
     NATIVE_WINDOW_SET_BUFFER_COUNT,
     NATIVE_WINDOW_SET_BUFFERS_GEOMETRY,
     NATIVE_WINDOW_SET_BUFFERS_TRANSFORM,
+    NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP,
 };
 
 /* parameter for NATIVE_WINDOW_[DIS]CONNECT */
@@ -157,7 +158,15 @@
     NATIVE_WINDOW_SURFACE_TEXTURE_CLIENT,       // SurfaceTextureClient
 };
 
-struct ANativeWindow 
+/* parameter for NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP
+ *
+ * Special timestamp value to indicate that timestamps should be auto-generated
+ * by the native window when queueBuffer is called.  This is equal to INT64_MIN,
+ * defined directly to avoid problems with C99/C++ inclusion of stdint.h.
+ */
+const int64_t NATIVE_WINDOW_TIMESTAMP_AUTO = (-9223372036854775807LL-1);
+
+struct ANativeWindow
 {
 #ifdef __cplusplus
     ANativeWindow()
@@ -262,7 +271,8 @@
      *     NATIVE_WINDOW_SET_BUFFER_COUNT
      *     NATIVE_WINDOW_SET_BUFFERS_GEOMETRY
      *     NATIVE_WINDOW_SET_BUFFERS_TRANSFORM
-     *  
+     *     NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP
+     *
      */
     
     int     (*perform)(struct ANativeWindow* window,
@@ -389,6 +399,22 @@
             transform);
 }
 
+/*
+ * native_window_set_buffers_timestamp(..., int64_t timestamp)
+ * All buffers queued after this call will be associated with the timestamp
+ * parameter specified. If the timestamp is set to NATIVE_WINDOW_TIMESTAMP_AUTO
+ * (the default), timestamps will be generated automatically when queueBuffer is
+ * called. The timestamp is measured in nanoseconds, and must be monotonically
+ * increasing.
+ */
+static inline int native_window_set_buffers_timestamp(
+        ANativeWindow* window,
+        int64_t timestamp)
+{
+    return window->perform(window, NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP,
+            timestamp);
+}
+
 // ---------------------------------------------------------------------------
 
 /* FIXME: this is legacy for pixmaps */
diff --git a/libs/gui/ISurfaceTexture.cpp b/libs/gui/ISurfaceTexture.cpp
index d661fd5..bc14ad5 100644
--- a/libs/gui/ISurfaceTexture.cpp
+++ b/libs/gui/ISurfaceTexture.cpp
@@ -88,10 +88,11 @@
         return result;
     }
 
-    virtual status_t queueBuffer(int buf) {
+    virtual status_t queueBuffer(int buf, int64_t timestamp) {
         Parcel data, reply;
         data.writeInterfaceToken(ISurfaceTexture::getInterfaceDescriptor());
         data.writeInt32(buf);
+        data.writeInt64(timestamp);
         remote()->transact(QUEUE_BUFFER, data, &reply);
         status_t result = reply.readInt32();
         return result;
@@ -174,7 +175,8 @@
         case QUEUE_BUFFER: {
             CHECK_INTERFACE(ISurfaceTexture, data, reply);
             int buf = data.readInt32();
-            status_t result = queueBuffer(buf);
+            int64_t timestamp = data.readInt64();
+            status_t result = queueBuffer(buf, timestamp);
             reply->writeInt32(result);
             return NO_ERROR;
         } break;
@@ -196,7 +198,6 @@
             return NO_ERROR;
         } break;
         case SET_TRANSFORM: {
-            Rect reg;
             CHECK_INTERFACE(ISurfaceTexture, data, reply);
             uint32_t transform = data.readInt32();
             status_t result = setTransform(transform);
diff --git a/libs/gui/SurfaceTexture.cpp b/libs/gui/SurfaceTexture.cpp
index 5c6d71b..cdaca47 100644
--- a/libs/gui/SurfaceTexture.cpp
+++ b/libs/gui/SurfaceTexture.cpp
@@ -76,9 +76,15 @@
 static void mtxMul(float out[16], const float a[16], const float b[16]);
 
 SurfaceTexture::SurfaceTexture(GLuint tex) :
-    mBufferCount(MIN_BUFFER_SLOTS), mCurrentTexture(INVALID_BUFFER_SLOT),
-    mCurrentTransform(0), mLastQueued(INVALID_BUFFER_SLOT),
-    mLastQueuedTransform(0), mNextTransform(0), mTexName(tex) {
+    mBufferCount(MIN_BUFFER_SLOTS),
+    mCurrentTexture(INVALID_BUFFER_SLOT),
+    mCurrentTransform(0),
+    mCurrentTimestamp(0),
+    mLastQueued(INVALID_BUFFER_SLOT),
+    mLastQueuedTransform(0),
+    mLastQueuedTimestamp(0),
+    mNextTransform(0),
+    mTexName(tex) {
     LOGV("SurfaceTexture::SurfaceTexture");
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
         mSlots[i].mEglImage = EGL_NO_IMAGE_KHR;
@@ -153,7 +159,7 @@
     return OK;
 }
 
-status_t SurfaceTexture::queueBuffer(int buf) {
+status_t SurfaceTexture::queueBuffer(int buf, int64_t timestamp) {
     LOGV("SurfaceTexture::queueBuffer");
     Mutex::Autolock lock(mMutex);
     if (buf < 0 || mBufferCount <= buf) {
@@ -172,6 +178,7 @@
     mLastQueued = buf;
     mLastQueuedCrop = mNextCrop;
     mLastQueuedTransform = mNextTransform;
+    mLastQueuedTimestamp = timestamp;
     if (mFrameAvailableListener != 0) {
         mFrameAvailableListener->onFrameAvailable();
     }
@@ -246,12 +253,13 @@
         mCurrentTextureBuf = mSlots[mCurrentTexture].mGraphicBuffer;
         mCurrentCrop = mLastQueuedCrop;
         mCurrentTransform = mLastQueuedTransform;
+        mCurrentTimestamp = mLastQueuedTimestamp;
     }
     return OK;
 }
 
 void SurfaceTexture::getTransformMatrix(float mtx[16]) {
-    LOGV("SurfaceTexture::updateTexImage");
+    LOGV("SurfaceTexture::getTransformMatrix");
     Mutex::Autolock lock(mMutex);
 
     float xform[16];
@@ -342,6 +350,12 @@
     mtxMul(mtx, mtxFlipV, mtxBeforeFlipV);
 }
 
+nsecs_t SurfaceTexture::getTimestamp() {
+    LOGV("SurfaceTexture::getTimestamp");
+    Mutex::Autolock lock(mMutex);
+    return mCurrentTimestamp;
+}
+
 void SurfaceTexture::setFrameAvailableListener(
         const sp<FrameAvailableListener>& l) {
     LOGV("SurfaceTexture::setFrameAvailableListener");
diff --git a/libs/gui/SurfaceTextureClient.cpp b/libs/gui/SurfaceTextureClient.cpp
index 7f1d9cb..a4812d0 100644
--- a/libs/gui/SurfaceTextureClient.cpp
+++ b/libs/gui/SurfaceTextureClient.cpp
@@ -26,7 +26,8 @@
 SurfaceTextureClient::SurfaceTextureClient(
         const sp<ISurfaceTexture>& surfaceTexture):
         mSurfaceTexture(surfaceTexture), mAllocator(0), mReqWidth(1),
-        mReqHeight(1), mReqFormat(DEFAULT_FORMAT), mReqUsage(0), mMutex() {
+        mReqHeight(1), mReqFormat(DEFAULT_FORMAT), mReqUsage(0),
+        mTimestamp(NATIVE_WINDOW_TIMESTAMP_AUTO), mMutex() {
     // Initialize the ANativeWindow function pointers.
     ANativeWindow::setSwapInterval  = setSwapInterval;
     ANativeWindow::dequeueBuffer    = dequeueBuffer;
@@ -135,9 +136,17 @@
 int SurfaceTextureClient::queueBuffer(android_native_buffer_t* buffer) {
     LOGV("SurfaceTextureClient::queueBuffer");
     Mutex::Autolock lock(mMutex);
+    int64_t timestamp;
+    if (mTimestamp == NATIVE_WINDOW_TIMESTAMP_AUTO) {
+        timestamp = systemTime(SYSTEM_TIME_MONOTONIC);
+        LOGV("SurfaceTextureClient::queueBuffer making up timestamp: %.2f ms",
+             timestamp / 1000000.f);
+    } else {
+        timestamp = mTimestamp;
+    }
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
         if (mSlots[i]->handle == buffer->handle) {
-            return mSurfaceTexture->queueBuffer(i);
+            return mSurfaceTexture->queueBuffer(i, timestamp);
         }
     }
     LOGE("queueBuffer: unknown buffer queued");
@@ -196,6 +205,9 @@
     case NATIVE_WINDOW_SET_BUFFERS_TRANSFORM:
         res = dispatchSetBuffersTransform(args);
         break;
+    case NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP:
+        res = dispatchSetBuffersTimestamp(args);
+        break;
     default:
         res = NAME_NOT_FOUND;
         break;
@@ -240,6 +252,11 @@
     return setBuffersTransform(transform);
 }
 
+int SurfaceTextureClient::dispatchSetBuffersTimestamp(va_list args) {
+    int64_t timestamp = va_arg(args, int64_t);
+    return setBuffersTimestamp(timestamp);
+}
+
 int SurfaceTextureClient::connect(int api) {
     LOGV("SurfaceTextureClient::connect");
     // XXX: Implement this!
@@ -323,6 +340,14 @@
     return err;
 }
 
+int SurfaceTextureClient::setBuffersTimestamp(int64_t timestamp)
+{
+    LOGV("SurfaceTextureClient::setBuffersTimestamp");
+    Mutex::Autolock lock(mMutex);
+    mTimestamp = timestamp;
+    return NO_ERROR;
+}
+
 void SurfaceTextureClient::freeAllBuffers() {
     for (int i = 0; i < NUM_BUFFER_SLOTS; i++) {
         mSlots[i] = 0;
diff --git a/libs/surfaceflinger_client/Surface.cpp b/libs/surfaceflinger_client/Surface.cpp
index 21d509a..0dfbf01 100644
--- a/libs/surfaceflinger_client/Surface.cpp
+++ b/libs/surfaceflinger_client/Surface.cpp
@@ -753,6 +753,9 @@
     case NATIVE_WINDOW_SET_BUFFERS_TRANSFORM:
         res = dispatch_set_buffers_transform( args );
         break;
+    case NATIVE_WINDOW_SET_BUFFERS_TIMESTAMP:
+        res = dispatch_set_buffers_timestamp( args );
+        break;
     default:
         res = NAME_NOT_FOUND;
         break;
@@ -792,6 +795,11 @@
     return setBuffersTransform(transform);
 }
 
+int Surface::dispatch_set_buffers_timestamp(va_list args) {
+    int64_t timestamp = va_arg(args, int64_t);
+    return setBuffersTimestamp(timestamp);
+}
+
 void Surface::setUsage(uint32_t reqUsage)
 {
     Mutex::Autolock _l(mSurfaceLock);
@@ -910,6 +918,13 @@
     return NO_ERROR;
 }
 
+int Surface::setBuffersTimestamp(int64_t timestamp)
+{
+    // Surface doesn't really have anything meaningful to do with timestamps
+    // so they'll just be dropped here.
+    return NO_ERROR;
+}
+
 // ----------------------------------------------------------------------------
 
 int Surface::getConnectedApi() const