diff --git a/media/libaudioprocessing/AudioMixer.cpp b/media/libaudioprocessing/AudioMixer.cpp
index 365af75..2567b3b 100644
--- a/media/libaudioprocessing/AudioMixer.cpp
+++ b/media/libaudioprocessing/AudioMixer.cpp
@@ -136,6 +136,9 @@
 
         // no initialization needed
         // t->frameCount
+        t->mHapticChannelMask = channelMask & AUDIO_CHANNEL_HAPTIC_ALL;
+        t->mHapticChannelCount = audio_channel_count_from_out_mask(t->mHapticChannelMask);
+        channelMask &= ~AUDIO_CHANNEL_HAPTIC_ALL;
         t->channelCount = audio_channel_count_from_out_mask(channelMask);
         t->enabled = false;
         ALOGV_IF(audio_channel_mask_get_bits(channelMask) != AUDIO_CHANNEL_OUT_STEREO,
@@ -163,10 +166,13 @@
         t->mMixerChannelCount = audio_channel_count_from_out_mask(t->mMixerChannelMask);
         t->mPlaybackRate = AUDIO_PLAYBACK_RATE_DEFAULT;
         // haptic
-        t->mAdjustInChannelCount = 0;
-        t->mAdjustOutChannelCount = 0;
-        t->mAdjustNonDestructiveInChannelCount = 0;
-        t->mAdjustNonDestructiveOutChannelCount = 0;
+        t->mHapticPlaybackEnabled = false;
+        t->mMixerHapticChannelMask = AUDIO_CHANNEL_NONE;
+        t->mMixerHapticChannelCount = 0;
+        t->mAdjustInChannelCount = t->channelCount + t->mHapticChannelCount;
+        t->mAdjustOutChannelCount = t->channelCount + t->mMixerHapticChannelCount;
+        t->mAdjustNonDestructiveInChannelCount = t->mAdjustOutChannelCount;
+        t->mAdjustNonDestructiveOutChannelCount = t->channelCount;
         t->mKeepContractedChannels = false;
         // Check the downmixing (or upmixing) requirements.
         status_t status = t->prepareForDownmix();
@@ -193,13 +199,20 @@
     LOG_ALWAYS_FATAL_IF(!exists(name), "invalid name: %d", name);
     const std::shared_ptr<Track> &track = mTracks[name];
 
-    if (trackChannelMask == track->channelMask
-            && mixerChannelMask == track->mMixerChannelMask) {
+    if (trackChannelMask == (track->channelMask | track->mHapticChannelMask)
+            && mixerChannelMask == (track->mMixerChannelMask | track->mMixerHapticChannelMask)) {
         return false;  // no need to change
     }
+    const audio_channel_mask_t hapticChannelMask = trackChannelMask & AUDIO_CHANNEL_HAPTIC_ALL;
+    trackChannelMask &= ~AUDIO_CHANNEL_HAPTIC_ALL;
+    const audio_channel_mask_t mixerHapticChannelMask = mixerChannelMask & AUDIO_CHANNEL_HAPTIC_ALL;
+    mixerChannelMask &= ~AUDIO_CHANNEL_HAPTIC_ALL;
     // always recompute for both channel masks even if only one has changed.
     const uint32_t trackChannelCount = audio_channel_count_from_out_mask(trackChannelMask);
     const uint32_t mixerChannelCount = audio_channel_count_from_out_mask(mixerChannelMask);
+    const uint32_t hapticChannelCount = audio_channel_count_from_out_mask(hapticChannelMask);
+    const uint32_t mixerHapticChannelCount =
+            audio_channel_count_from_out_mask(mixerHapticChannelMask);
 
     ALOG_ASSERT((trackChannelCount <= MAX_NUM_CHANNELS_TO_DOWNMIX)
             && trackChannelCount
@@ -208,6 +221,24 @@
     track->channelCount = trackChannelCount;
     track->mMixerChannelMask = mixerChannelMask;
     track->mMixerChannelCount = mixerChannelCount;
+    track->mHapticChannelMask = hapticChannelMask;
+    track->mHapticChannelCount = hapticChannelCount;
+    track->mMixerHapticChannelMask = mixerHapticChannelMask;
+    track->mMixerHapticChannelCount = mixerHapticChannelCount;
+
+    if (track->mHapticChannelCount > 0) {
+        track->mAdjustInChannelCount = track->channelCount + track->mHapticChannelCount;
+        track->mAdjustOutChannelCount = track->channelCount + track->mMixerHapticChannelCount;
+        track->mAdjustNonDestructiveInChannelCount = track->mAdjustOutChannelCount;
+        track->mAdjustNonDestructiveOutChannelCount = track->channelCount;
+        track->mKeepContractedChannels = track->mHapticPlaybackEnabled;
+    } else {
+        track->mAdjustInChannelCount = 0;
+        track->mAdjustOutChannelCount = 0;
+        track->mAdjustNonDestructiveInChannelCount = 0;
+        track->mAdjustNonDestructiveOutChannelCount = 0;
+        track->mKeepContractedChannels = false;
+    }
 
     // channel masks have changed, does this track need a downmixer?
     // update to try using our desired format (if we aren't already using it)
@@ -616,7 +647,8 @@
         case CHANNEL_MASK: {
             const audio_channel_mask_t trackChannelMask =
                 static_cast<audio_channel_mask_t>(valueInt);
-            if (setChannelMasks(name, trackChannelMask, track->mMixerChannelMask)) {
+            if (setChannelMasks(name, trackChannelMask,
+                    (track->mMixerChannelMask | track->mMixerHapticChannelMask))) {
                 ALOGV("setParameter(TRACK, CHANNEL_MASK, %x)", trackChannelMask);
                 invalidate();
             }
@@ -665,11 +697,21 @@
         case MIXER_CHANNEL_MASK: {
             const audio_channel_mask_t mixerChannelMask =
                     static_cast<audio_channel_mask_t>(valueInt);
-            if (setChannelMasks(name, track->channelMask, mixerChannelMask)) {
+            if (setChannelMasks(name, track->channelMask | track->mHapticChannelMask,
+                    mixerChannelMask)) {
                 ALOGV("setParameter(TRACK, MIXER_CHANNEL_MASK, %#x)", mixerChannelMask);
                 invalidate();
             }
             } break;
+        case HAPTIC_ENABLED: {
+            const bool hapticPlaybackEnabled = static_cast<bool>(valueInt);
+            if (track->mHapticPlaybackEnabled != hapticPlaybackEnabled) {
+                track->mHapticPlaybackEnabled = hapticPlaybackEnabled;
+                track->mKeepContractedChannels = hapticPlaybackEnabled;
+                track->prepareForAdjustChannelsNonDestructive(mFrameCount);
+                track->prepareForAdjustChannels();
+            }
+            } break;
         default:
             LOG_ALWAYS_FATAL("setParameter track: bad param %d", param);
         }
@@ -1359,8 +1401,8 @@
 
         const std::shared_ptr<Track> &t = mTracks[group[0]];
         memset(t->mainBuffer, 0,
-                mFrameCount * t->mMixerChannelCount
-                * audio_bytes_per_sample(t->mMixerFormat));
+                mFrameCount * audio_bytes_per_frame(
+                        t->mMixerChannelCount + t->mMixerHapticChannelCount, t->mMixerFormat));
 
         // now consume data
         for (const int name : group) {