5 files changed, 79 insertions, 17 deletions
diff --git a/include/gui/BufferQueue.h b/include/gui/BufferQueue.h
index 99147cd..da876ec 100644
--- a/include/gui/BufferQueue.h
+++ b/include/gui/BufferQueue.h
@@ -228,16 +228,8 @@ public:
     // will usually be the one obtained from dequeueBuffer.
     virtual void cancelBuffer(int buf, const sp<Fence>& fence);
 
-    // connect attempts to connect a producer API to the BufferQueue.  This
-    // must be called before any other IGraphicBufferProducer methods are
-    // called except for getAllocator.  A consumer must already be connected.
-    //
-    // This method will fail if connect was previously called on the
-    // BufferQueue and no corresponding disconnect call was made (i.e. if
-    // it's still connected to a producer).
-    //
-    // APIs are enumerated in window.h (e.g. NATIVE_WINDOW_API_CPU).
-    virtual status_t connect(const sp<IBinder>& token,
+    // See IGraphicBufferProducer::connect
+    virtual status_t connect(const sp<IProducerListener>& listener,
             int api, bool producerControlledByApp, QueueBufferOutput* output);
 
     // disconnect attempts to disconnect a producer API from the BufferQueue.
diff --git a/include/gui/BufferQueueCore.h b/include/gui/BufferQueueCore.h
index 89f2779..cfcb7a5 100644
--- a/include/gui/BufferQueueCore.h
+++ b/include/gui/BufferQueueCore.h
@@ -46,9 +46,9 @@
 namespace android {
 
 class BufferItem;
-class IBinder;
 class IConsumerListener;
 class IGraphicBufferAlloc;
+class IProducerListener;
 
 class BufferQueueCore : public virtual RefBase {
 
@@ -162,7 +162,7 @@ private:
 
     // mConnectedProducerToken is used to set a binder death notification on
     // the producer.
-    sp<IBinder> mConnectedProducerToken;
+    sp<IProducerListener> mConnectedProducerListener;
 
     // mSlots is an array of buffer slots that must be mirrored on the producer
     // side. This allows buffer ownership to be transferred between the producer
diff --git a/include/gui/BufferQueueProducer.h b/include/gui/BufferQueueProducer.h
index 0013b0a..04692a5 100644
--- a/include/gui/BufferQueueProducer.h
+++ b/include/gui/BufferQueueProducer.h
@@ -140,7 +140,7 @@ public:
     // it's still connected to a producer).
     //
     // APIs are enumerated in window.h (e.g. NATIVE_WINDOW_API_CPU).
-    virtual status_t connect(const sp<IBinder>& token,
+    virtual status_t connect(const sp<IProducerListener>& listener,
             int api, bool producerControlledByApp, QueueBufferOutput* output);
 
     // disconnect attempts to disconnect a producer API from the BufferQueue.
diff --git a/include/gui/IGraphicBufferProducer.h b/include/gui/IGraphicBufferProducer.h
index 0874f03..2b61ab3 100644
--- a/include/gui/IGraphicBufferProducer.h
+++ b/include/gui/IGraphicBufferProducer.h
@@ -32,6 +32,7 @@
 namespace android {
 // ----------------------------------------------------------------------------
 
+class IProducerListener;
 class NativeHandle;
 class Surface;
 
@@ -344,9 +345,11 @@ public:
     // This method will fail if the connect was previously called on the
     // IGraphicBufferProducer and no corresponding disconnect call was made.
     //
-    // The token needs to be any opaque binder object that lives in the
-    // producer process -- it is solely used for obtaining a death notification
-    // when the producer is killed.
+    // The listener is an optional binder callback object that can be used if
+    // the producer wants to be notified when the consumer releases a buffer
+    // back to the BufferQueue. It is also used to detect the death of the
+    // producer. If only the latter functionality is desired, there is a
+    // DummyProducerListener class in IProducerListener.h that can be used.
     //
     // The api should be one of the NATIVE_WINDOW_API_* values in <window.h>
     //
@@ -370,7 +373,7 @@ public:
     //
     // Additional negative errors may be returned by the internals, they
     // should be treated as opaque fatal unrecoverable errors.
-    virtual status_t connect(const sp<IBinder>& token,
+    virtual status_t connect(const sp<IProducerListener>& listener,
             int api, bool producerControlledByApp, QueueBufferOutput* output) = 0;
 
     // disconnect attempts to disconnect a client API from the
diff --git a/include/gui/IProducerListener.h b/include/gui/IProducerListener.h
new file mode 100644
index 0000000..3848a6c
--- /dev/null
+++ b/include/gui/IProducerListener.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2014 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_GUI_IPRODUCERLISTENER_H
+#define ANDROID_GUI_IPRODUCERLISTENER_H
+
+#include <binder/IInterface.h>
+
+#include <utils/RefBase.h>
+
+namespace android {
+
+// ProducerListener is the interface through which the BufferQueue notifies the
+// producer of events that the producer may wish to react to. Because the
+// producer will generally have a mutex that is locked during calls from the
+// producer to the BufferQueue, these calls from the BufferQueue to the
+// producer *MUST* be called only when the BufferQueue mutex is NOT locked.
+
+class ProducerListener : public virtual RefBase
+{
+public:
+    ProducerListener() {}
+    virtual ~ProducerListener() {}
+
+    // onBufferReleased is called from IGraphicBufferConsumer::releaseBuffer to
+    // notify the producer that a new buffer is free and ready to be dequeued.
+    //
+    // This is called without any lock held and can be called concurrently by
+    // multiple threads.
+    virtual void onBufferReleased() = 0; // Asynchronous
+};
+
+class IProducerListener : public ProducerListener, public IInterface
+{
+public:
+    DECLARE_META_INTERFACE(ProducerListener)
+};
+
+class BnProducerListener : public BnInterface<IProducerListener>
+{
+public:
+    virtual status_t onTransact(uint32_t code, const Parcel& data,
+            Parcel* reply, uint32_t flags = 0);
+};
+
+class DummyProducerListener : public BnProducerListener
+{
+public:
+    virtual void onBufferReleased() {}
+};
+
+} // namespace android
+
+#endif