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Change-Id: Ifbf3a46a4183c8abc0feee1c588953ab10303cc1

3 files changed, 15 insertions, 1 deletions

diff --git a/include/media/AudioTrack.h b/include/media/AudioTrack.h
index 6727601..58e0deb 100644
--- a/include/media/AudioTrack.h
+++ b/include/media/AudioTrack.h
@@ -75,8 +75,10 @@ public:
         size_t      frameCount;   // number of sample frames corresponding to size;
                                   // on input it is the number of frames desired,
                                   // on output is the number of frames actually filled
+                                  // (currently ignored, but will make the primary field in future)
 
         size_t      size;         // input/output in bytes == frameCount * frameSize
+                                  // on output is the number of bytes actually filled
                                   // FIXME this is redundant with respect to frameCount,
                                   // and TRANSFER_OBTAIN mode is broken for 8-bit data
                                   // since we don't define the frame format
diff --git a/include/media/IAudioFlinger.h b/include/media/IAudioFlinger.h
index f8a9f2b..0aa5870 100644
--- a/include/media/IAudioFlinger.h
+++ b/include/media/IAudioFlinger.h
@@ -125,7 +125,9 @@ public:
     virtual     String8     getParameters(audio_io_handle_t ioHandle, const String8& keys)
                                     const = 0;
 
-    // register a current process for audio output change notifications
+    // Register an object to receive audio input/output change and track notifications.
+    // For a given calling pid, AudioFlinger disregards any registrations after the first.
+    // Thus the IAudioFlingerClient must be a singleton per process.
     virtual void registerClient(const sp<IAudioFlingerClient>& client) = 0;
 
     // retrieve the audio recording buffer size
diff --git a/include/media/nbaio/NBLog.h b/include/media/nbaio/NBLog.h
index 107ba66..6d59ea7 100644
--- a/include/media/nbaio/NBLog.h
+++ b/include/media/nbaio/NBLog.h
@@ -90,6 +90,8 @@ public:
     virtual ~Timeline();
 #endif
 
+    // Input parameter 'size' is the desired size of the timeline in byte units.
+    // Returns the size rounded up to a power-of-2, plus the constant size overhead for indices.
     static size_t sharedSize(size_t size);
 
 #if 0
@@ -110,8 +112,12 @@ private:
 class Writer : public RefBase {
 public:
     Writer();                   // dummy nop implementation without shared memory
+
+    // Input parameter 'size' is the desired size of the timeline in byte units.
+    // The size of the shared memory must be at least Timeline::sharedSize(size).
     Writer(size_t size, void *shared);
     Writer(size_t size, const sp<IMemory>& iMemory);
+
     virtual ~Writer() { }
 
     virtual void    log(const char *string);
@@ -165,8 +171,12 @@ private:
 
 class Reader : public RefBase {
 public:
+
+    // Input parameter 'size' is the desired size of the timeline in byte units.
+    // The size of the shared memory must be at least Timeline::sharedSize(size).
     Reader(size_t size, const void *shared);
     Reader(size_t size, const sp<IMemory>& iMemory);
+
     virtual ~Reader() { }
 
     void    dump(int fd, size_t indent = 0);