diff --git a/services/audioflinger/FastMixer.h b/services/audioflinger/FastMixer.h
index 7aeddef..981c1a7 100644
--- a/services/audioflinger/FastMixer.h
+++ b/services/audioflinger/FastMixer.h
@@ -18,123 +18,65 @@
 #define ANDROID_AUDIO_FAST_MIXER_H
 
 #include <utils/Debug.h>
+#if 1   // FIXME move to where used
 extern "C" {
 #include "../private/bionic_futex.h"
 }
+#endif
 #include "FastThread.h"
 #include "StateQueue.h"
 #include "FastMixerState.h"
+#include "FastMixerDumpState.h"
 
 namespace android {
 
+class AudioMixer;
+
 typedef StateQueue<FastMixerState> FastMixerStateQueue;
 
 class FastMixer : public FastThread {
 
 public:
-            FastMixer() : FastThread() { }
-    virtual ~FastMixer() { }
+            FastMixer();
+    virtual ~FastMixer();
 
-            FastMixerStateQueue* sq() { return &mSQ; }
+            FastMixerStateQueue* sq();
 
 private:
-    virtual bool                threadLoop();
             FastMixerStateQueue mSQ;
 
+    // callouts
+    virtual const FastThreadState *poll();
+    virtual void setLog(NBLog::Writer *logWriter);
+    virtual void onIdle();
+    virtual void onExit();
+    virtual bool isSubClassCommand(FastThreadState::Command command);
+    virtual void onStateChange();
+    virtual void onWork();
+
+    // FIXME these former local variables need comments and to be renamed to have "m" prefix
+    static const FastMixerState initial;
+    FastMixerState preIdle; // copy of state before we went into idle
+    long slopNs;        // accumulated time we've woken up too early (> 0) or too late (< 0)
+    int fastTrackNames[FastMixerState::kMaxFastTracks]; // handles used by mixer to identify tracks
+    int generations[FastMixerState::kMaxFastTracks];    // last observed mFastTracks[i].mGeneration
+    NBAIO_Sink *outputSink;
+    int outputSinkGen;
+    AudioMixer* mixer;
+    short *mixBuffer;
+    enum {UNDEFINED, MIXED, ZEROED} mixBufferState;
+    NBAIO_Format format;
+    unsigned sampleRate;
+    int fastTracksGen;
+    FastMixerDumpState dummyDumpState;
+    uint32_t totalNativeFramesWritten;  // copied to dumpState->mFramesWritten
+
+    // next 2 fields are valid only when timestampStatus == NO_ERROR
+    AudioTimestamp timestamp;
+    uint32_t nativeFramesWrittenButNotPresented;
+
 };  // class FastMixer
 
-// Describes the underrun status for a single "pull" attempt
-enum FastTrackUnderrunStatus {
-    UNDERRUN_FULL,      // framesReady() is full frame count, no underrun
-    UNDERRUN_PARTIAL,   // framesReady() is non-zero but < full frame count, partial underrun
-    UNDERRUN_EMPTY,     // framesReady() is zero, total underrun
-};
-
-// Underrun counters are not reset to zero for new tracks or if track generation changes.
-// This packed representation is used to keep the information atomic.
-union FastTrackUnderruns {
-    FastTrackUnderruns() { mAtomic = 0;
-            COMPILE_TIME_ASSERT_FUNCTION_SCOPE(sizeof(FastTrackUnderruns) == sizeof(uint32_t)); }
-    FastTrackUnderruns(const FastTrackUnderruns& copyFrom) : mAtomic(copyFrom.mAtomic) { }
-    FastTrackUnderruns& operator=(const FastTrackUnderruns& rhs)
-            { if (this != &rhs) mAtomic = rhs.mAtomic; return *this; }
-    struct {
-#define UNDERRUN_BITS 10
-#define UNDERRUN_MASK ((1 << UNDERRUN_BITS) - 1)
-        uint32_t mFull    : UNDERRUN_BITS; // framesReady() is full frame count
-        uint32_t mPartial : UNDERRUN_BITS; // framesReady() is non-zero but < full frame count
-        uint32_t mEmpty   : UNDERRUN_BITS; // framesReady() is zero
-        FastTrackUnderrunStatus mMostRecent : 2;    // status of most recent framesReady()
-    }        mBitFields;
-private:
-    uint32_t mAtomic;
-};
-
-// Represents the dump state of a fast track
-struct FastTrackDump {
-    FastTrackDump() : mFramesReady(0) { }
-    /*virtual*/ ~FastTrackDump() { }
-    FastTrackUnderruns mUnderruns;
-    size_t mFramesReady;        // most recent value only; no long-term statistics kept
-};
-
-// The FastMixerDumpState keeps a cache of FastMixer statistics that can be logged by dumpsys.
-// Each individual native word-sized field is accessed atomically.  But the
-// overall structure is non-atomic, that is there may be an inconsistency between fields.
-// No barriers or locks are used for either writing or reading.
-// Only POD types are permitted, and the contents shouldn't be trusted (i.e. do range checks).
-// It has a different lifetime than the FastMixer, and so it can't be a member of FastMixer.
-struct FastMixerDumpState {
-    FastMixerDumpState(
-#ifdef FAST_MIXER_STATISTICS
-            uint32_t samplingN = kSamplingNforLowRamDevice
-#endif
-            );
-    /*virtual*/ ~FastMixerDumpState();
-
-    void dump(int fd) const;    // should only be called on a stable copy, not the original
-
-    FastMixerState::Command mCommand;   // current command
-    uint32_t mWriteSequence;    // incremented before and after each write()
-    uint32_t mFramesWritten;    // total number of frames written successfully
-    uint32_t mNumTracks;        // total number of active fast tracks
-    uint32_t mWriteErrors;      // total number of write() errors
-    uint32_t mUnderruns;        // total number of underruns
-    uint32_t mOverruns;         // total number of overruns
-    uint32_t mSampleRate;
-    size_t   mFrameCount;
-    struct timespec mMeasuredWarmupTs;  // measured warmup time
-    uint32_t mWarmupCycles;     // number of loop cycles required to warmup
-    uint32_t mTrackMask;        // mask of active tracks
-    FastTrackDump   mTracks[FastMixerState::kMaxFastTracks];
-
-#ifdef FAST_MIXER_STATISTICS
-    // Recently collected samples of per-cycle monotonic time, thread CPU time, and CPU frequency.
-    // kSamplingN is max size of sampling frame (statistics), and must be a power of 2 <= 0x8000.
-    // The sample arrays are virtually allocated based on this compile-time constant,
-    // but are only initialized and used based on the runtime parameter mSamplingN.
-    static const uint32_t kSamplingN = 0x8000;
-    // Compile-time constant for a "low RAM device", must be a power of 2 <= kSamplingN.
-    // This value was chosen such that each array uses 1 small page (4 Kbytes).
-    static const uint32_t kSamplingNforLowRamDevice = 0x400;
-    // Corresponding runtime maximum size of sample arrays, must be a power of 2 <= kSamplingN.
-    uint32_t mSamplingN;
-    // The bounds define the interval of valid samples, and are represented as follows:
-    //      newest open (excluded) endpoint   = lower 16 bits of bounds, modulo N
-    //      oldest closed (included) endpoint = upper 16 bits of bounds, modulo N
-    // Number of valid samples is newest - oldest.
-    uint32_t mBounds;                   // bounds for mMonotonicNs, mThreadCpuNs, and mCpukHz
-    // The elements in the *Ns arrays are in units of nanoseconds <= 3999999999.
-    uint32_t mMonotonicNs[kSamplingN];  // delta monotonic (wall clock) time
-    uint32_t mLoadNs[kSamplingN];       // delta CPU load in time
-#ifdef CPU_FREQUENCY_STATISTICS
-    uint32_t mCpukHz[kSamplingN];       // absolute CPU clock frequency in kHz, bits 0-3 are CPU#
-#endif
-    // Increase sampling window after construction, must be a power of 2 <= kSamplingN
-    void    increaseSamplingN(uint32_t samplingN);
-#endif
-};
-
 }   // namespace android
 
 #endif  // ANDROID_AUDIO_FAST_MIXER_H