diff --git a/include/media/MmapStreamCallback.h b/include/media/MmapStreamCallback.h
new file mode 100644
index 0000000..8098e79
--- /dev/null
+++ b/include/media/MmapStreamCallback.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_AUDIO_MMAP_STREAM_CALLBACK_H
+#define ANDROID_AUDIO_MMAP_STREAM_CALLBACK_H
+
+#include <system/audio.h>
+#include <utils/Errors.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+
+class MmapStreamCallback : public virtual RefBase {
+  public:
+
+    /**
+     * The mmap stream should be torn down because conditions that permitted its creation with
+     * the requested parameters have changed and do not allow it to operate with the requested
+     * constraints any more.
+     */
+    virtual void onTearDown() = 0;
+
+    /**
+     * The volume to be applied to the use case specified when opening the stream has changed
+     * \param[in] channels a channel mask containing all channels the volume should be applied to.
+     * \param[in] values the volume values to be applied to each channel. The size of the vector
+     *                   should correspond to the channel count retrieved with
+     *                   audio_channel_count_from_in_mask() or audio_channel_count_from_out_mask()
+     */
+    virtual void onVolumeChanged(audio_channel_mask_t channels, Vector<float> values) = 0;
+
+    /**
+     * The device the stream is routed to/from has changed
+     * \param[in] onRoutingChanged the unique device ID of the new device.
+     */
+    virtual void onRoutingChanged(audio_port_handle_t deviceId) = 0;
+
+  protected:
+    MmapStreamCallback() {}
+    virtual ~MmapStreamCallback() {}
+};
+
+
+} // namespace android
+
+#endif // ANDROID_AUDIO_MMAP_STREAM_CALLBACK_H