diff --git a/configs/msmnile/audio_policy_configuration.xml b/configs/msmnile/audio_policy_configuration.xml
index 45598dc..a8ae093 100644
--- a/configs/msmnile/audio_policy_configuration.xml
+++ b/configs/msmnile/audio_policy_configuration.xml
@@ -370,7 +370,7 @@
                 <route type="mix" sink="USB Headset Out"
                        sources="primary output,raw,deep_buffer,direct_pcm,compressed_offload,voip_rx,mmap_no_irq_out,hifi_playback"/>
                 <route type="mix" sink="Telephony Tx"
-                       sources="voice_tx"/>
+                       sources="voice_tx,incall_music_uplink"/>
                 <route type="mix" sink="voice_rx"
                        sources="Telephony Rx"/>
                 <route type="mix" sink="primary input"
diff --git a/configs/msmnile/mixer_paths_tavil.xml b/configs/msmnile/mixer_paths_tavil.xml
index a3cf0e1..b2c8be2 100644
--- a/configs/msmnile/mixer_paths_tavil.xml
+++ b/configs/msmnile/mixer_paths_tavil.xml
@@ -2992,76 +2992,79 @@
         <ctl name="MultiMedia2 Mixer USB_AUDIO_TX" value="1" />
     </path>
 
-    <path name="incall-music-uplink">
+    <path name="incall_music_uplink">
         <ctl name="Incall_Music Audio Mixer MultiMedia9" value="1" />
     </path>
 
-    <path name="incall-music-uplink speaker">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink handset">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink handset">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink handset-hac">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink handset-hac">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink display-port">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink display-port">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink bt-sco">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink bt-sco">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink bt-sco-wb">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink bt-sco-wb">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink speaker-and-display-port">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker-and-display-port">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink afe-proxy">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink afe-proxy">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink usb-headphones">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink usb-headphones">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink usb-headset">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink usb-headset">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink speaker-and-usb-headphones">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker-and-usb-headphones">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink headphones">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink headphones">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink speaker-and-headphones">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker-and-headphones">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink speaker-and-bt-sco">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker-and-bt-sco">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink voice-tty-hco-handset">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink voice-tty-hco-handset">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink speaker-and-bt-a2dp">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink speaker-and-bt-a2dp">
+        <path name="incall_music_uplink" />
     </path>
 
-    <path name="incall-music-uplink bt-a2dp">
-        <path name="incall-music-uplink" />
+    <path name="incall_music_uplink bt-a2dp">
+        <path name="incall_music_uplink" />
     </path>
 
+    <path name="incall_music_uplink afe-proxy">
+        <path name="incall_music_uplink" />
+    </path>
 </mixer>
diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index d83002a..a0f37bc 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -2912,6 +2912,9 @@
             adev->offload_effects_stop_output(out->handle, out->pcm_device_id);
     }
 
+    if (out->usecase == USECASE_INCALL_MUSIC_UPLINK)
+        voice_set_device_mute_flag(adev, false);
+
     /* 1. Get and set stream specific mixer controls */
     disable_audio_route(adev, uc_info);
 
@@ -3071,6 +3074,9 @@
          select_devices(adev, out->usecase);
     }
 
+    if (out->usecase == USECASE_INCALL_MUSIC_UPLINK)
+        voice_set_device_mute_flag(adev, true);
+
     ALOGV("%s: Opening PCM device card_id(%d) device_id(%d) format(%#x)",
           __func__, adev->snd_card, out->pcm_device_id, out->config.format);
 
@@ -4358,6 +4364,8 @@
     struct audio_device *adev = out->dev;
     ssize_t ret = 0;
     int channels = 0;
+    const size_t frame_size = audio_stream_out_frame_size(stream);
+    const size_t frames = (frame_size != 0) ? bytes / frame_size : bytes;
 
     ATRACE_BEGIN("out_write");
     lock_output_stream(out);
@@ -4563,8 +4571,35 @@
         return ret;
     } else {
         if (out->pcm) {
+            size_t bytes_to_write = bytes;
             if (out->muted)
                 memset((void *)buffer, 0, bytes);
+            ALOGV("%s: frames=%zu, frame_size=%zu, bytes_to_write=%zu",
+                     __func__, frames, frame_size, bytes_to_write);
+
+            if (out->usecase == USECASE_INCALL_MUSIC_UPLINK) {
+                size_t channel_count = audio_channel_count_from_out_mask(out->channel_mask);
+                int16_t *src = (int16_t *)buffer;
+                int16_t *dst = (int16_t *)buffer;
+
+                LOG_ALWAYS_FATAL_IF(out->config.channels != 1 || channel_count != 2 ||
+                                    out->format != AUDIO_FORMAT_PCM_16_BIT,
+                                    "out_write called for incall music use case with wrong properties");
+
+                /*
+                 * FIXME: this can be removed once audio flinger mixer supports
+                 * mono output
+                 */
+
+                /*
+                 * Code below goes over each frame in the buffer and adds both
+                 * L and R samples and then divides by 2 to convert to mono
+                 */
+                for (size_t i = 0; i < frames ; i++, dst++, src += 2) {
+                    *dst = (int16_t)(((int32_t)src[0] + (int32_t)src[1]) >> 1);
+                }
+                bytes_to_write /= 2;
+            }
 
             ALOGVV("%s: writing buffer (%zu bytes) to pcm device", __func__, bytes);
 
@@ -4574,12 +4609,11 @@
                 ns = pcm_bytes_to_frames(out->pcm, bytes)*1000000000LL/
                                                      out->config.rate;
 
+            request_out_focus(out, ns);
             bool use_mmap = is_mmap_usecase(out->usecase) || out->realtime;
 
-            request_out_focus(out, ns);
-
             if (use_mmap)
-                ret = pcm_mmap_write(out->pcm, (void *)buffer, bytes);
+                ret = pcm_mmap_write(out->pcm, (void *)buffer, bytes_to_write);
             else if (out->hal_op_format != out->hal_ip_format &&
                        out->convert_buffer != NULL) {
 
@@ -4613,7 +4647,7 @@
                            out_get_sample_rate(&out->stream.common));
                     ret = 0;
                 } else
-                    ret = pcm_write(out->pcm, (void *)buffer, bytes);
+                    ret = pcm_write(out->pcm, (void *)buffer, bytes_to_write);
             }
 
             release_out_focus(out);
@@ -6119,13 +6153,55 @@
         create_offload_callback_thread(out);
 
     } else if (out->flags & AUDIO_OUTPUT_FLAG_INCALL_MUSIC) {
+          switch (config->sample_rate) {
+            case 0:
+                out->sample_rate = DEFAULT_OUTPUT_SAMPLING_RATE;
+                break;
+            case 8000:
+            case 16000:
+            case 48000:
+                out->sample_rate = config->sample_rate;
+                break;
+            default:
+                ALOGE("%s: Unsupported sampling rate %d for Incall Music", __func__,
+                      config->sample_rate);
+                config->sample_rate = DEFAULT_OUTPUT_SAMPLING_RATE;
+                ret = -EINVAL;
+                goto error_open;
+        }
+        //FIXME: add support for MONO stream configuration when audioflinger mixer supports it
+        switch (config->channel_mask) {
+            case AUDIO_CHANNEL_NONE:
+            case AUDIO_CHANNEL_OUT_STEREO:
+                out->channel_mask = AUDIO_CHANNEL_OUT_STEREO;
+                break;
+            default:
+                ALOGE("%s: Unsupported channel mask %#x for Incall Music", __func__,
+                      config->channel_mask);
+                config->channel_mask = AUDIO_CHANNEL_OUT_STEREO;
+                ret = -EINVAL;
+                goto error_open;
+        }
+        switch (config->format) {
+            case AUDIO_FORMAT_DEFAULT:
+            case AUDIO_FORMAT_PCM_16_BIT:
+                out->format = AUDIO_FORMAT_PCM_16_BIT;
+                break;
+            default:
+                ALOGE("%s: Unsupported format %#x for Incall Music", __func__,
+                      config->format);
+                config->format = AUDIO_FORMAT_PCM_16_BIT;
+                ret = -EINVAL;
+                goto error_open;
+        }
+
         ret = voice_extn_check_and_set_incall_music_usecase(adev, out);
         if (ret != 0) {
             ALOGE("%s: Incall music delivery usecase cannot be set error:%d",
-                  __func__, ret);
+                __func__, ret);
             goto error_open;
         }
-    } else  if (out->devices == AUDIO_DEVICE_OUT_TELEPHONY_TX) {
+    } else if (out->devices == AUDIO_DEVICE_OUT_TELEPHONY_TX) {
         if (config->sample_rate == 0)
             config->sample_rate = AFE_PROXY_SAMPLING_RATE;
         if (config->sample_rate != 48000 && config->sample_rate != 16000 &&
diff --git a/hal/voice.c b/hal/voice.c
index f9e3562..fc38ab2 100644
--- a/hal/voice.c
+++ b/hal/voice.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
  * Not a contribution.
  *
  * Copyright (C) 2013 The Android Open Source Project
@@ -228,6 +228,7 @@
 
     uc_info->in_snd_device = SND_DEVICE_NONE;
     uc_info->out_snd_device = SND_DEVICE_NONE;
+    adev->voice.use_device_mute = false;
 
     if (audio_is_bluetooth_sco_device(uc_info->devices) && !adev->bt_sco_on) {
         ALOGE("start_call: couldn't find BT SCO, SCO is not ready");
@@ -338,10 +339,10 @@
        return in_call_rec;
     }
 
-    if(in->source == AUDIO_SOURCE_VOICE_DOWNLINK ||
-       in->source == AUDIO_SOURCE_VOICE_UPLINK ||
-       in->source == AUDIO_SOURCE_VOICE_CALL) {
-       in_call_rec = true;
+    if (in->source == AUDIO_SOURCE_VOICE_DOWNLINK ||
+        in->source == AUDIO_SOURCE_VOICE_UPLINK ||
+        in->source == AUDIO_SOURCE_VOICE_CALL) {
+            in_call_rec = true;
     }
 
     return in_call_rec;
@@ -476,13 +477,21 @@
     int err = 0;
 
     adev->voice.mic_mute = state;
+
     if (audio_extn_hfp_is_active(adev)) {
         err = hfp_set_mic_mute(adev, state);
     } else if (adev->mode == AUDIO_MODE_IN_CALL) {
-        err = platform_set_mic_mute(adev->platform, state);
+       /* Use device mute if incall music delivery usecase is in progress */
+        if (adev->voice.use_device_mute)
+            err = platform_set_device_mute(adev->platform, state, "tx");
+        else
+            err = platform_set_mic_mute(adev->platform, state);
+        ALOGV("%s: voice mute status=%d, use_device_mute flag=%d",
+            __func__, state, adev->voice.use_device_mute);
     } else if (adev->mode == AUDIO_MODE_IN_COMMUNICATION) {
         err = voice_extn_compress_voip_set_mic_mute(adev, state);
     }
+
     return err;
 }
 
@@ -491,6 +500,27 @@
     return adev->voice.mic_mute;
 }
 
+/*
+ * Following function is called when incall music uplink usecase is
+ * created or destroyed while mic is muted. If incall music uplink
+ * usecase is active, apply voice device mute to mute only voice Tx
+ * path and not the mixed voice Tx + inncall-music path. Revert to
+ * voice stream mute once incall music uplink usecase is inactive
+ */
+void voice_set_device_mute_flag(struct audio_device *adev, bool state)
+{
+    if (adev->voice.mic_mute) {
+        if (state) {
+            platform_set_device_mute(adev->platform, true, "tx");
+            platform_set_mic_mute(adev->platform, false);
+        } else {
+            platform_set_mic_mute(adev->platform, true);
+            platform_set_device_mute(adev->platform, false, "tx");
+        }
+    }
+    adev->voice.use_device_mute = state;
+}
+
 int voice_set_volume(struct audio_device *adev, float volume)
 {
     int vol, err = 0;
diff --git a/hal/voice.h b/hal/voice.h
index 3ae42a8..2ef790a 100644
--- a/hal/voice.h
+++ b/hal/voice.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
  * Not a contribution.
  *
  * Copyright (C) 2013 The Android Open Source Project
@@ -61,6 +61,7 @@
     struct voice_session session[MAX_VOICE_SESSIONS];
     int tty_mode;
     bool mic_mute;
+    bool use_device_mute;
     float volume;
     bool in_call;
 };
@@ -101,4 +102,6 @@
                                       snd_device_t out_snd_device,
                                       bool enable);
 bool voice_is_call_state_active(struct audio_device *adev);
+void voice_set_device_mute_flag (struct audio_device *adev, bool state);
+
 #endif //VOICE_H
diff --git a/hal/voice_extn/voice_extn.c b/hal/voice_extn/voice_extn.c
index 93653ca..ec85259 100644
--- a/hal/voice_extn/voice_extn.c
+++ b/hal/voice_extn/voice_extn.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
  * Not a contribution.
  *
  * Copyright (C) 2013 The Android Open Source Project
@@ -594,27 +594,16 @@
     voice_extn_compress_voip_in_get_parameters(in, query, reply);
 }
 
-#ifdef INCALL_MUSIC_ENABLED
 int voice_extn_check_and_set_incall_music_usecase(struct audio_device *adev,
                                                   struct stream_out *out)
 {
-    uint32_t session_id = 0;
-
-    session_id = get_session_id_with_state(adev, CALL_LOCAL_HOLD);
-    if (session_id == VOICE_VSID) {
-        out->usecase = USECASE_INCALL_MUSIC_UPLINK;
-    } else if (session_id == VOICE2_VSID) {
-        out->usecase = USECASE_INCALL_MUSIC_UPLINK2;
-    } else {
-        ALOGE("%s: Invalid session id %x", __func__, session_id);
-        return -EINVAL;
-    }
-
+    out->usecase = USECASE_INCALL_MUSIC_UPLINK;
     out->config = pcm_config_incall_music;
-    out->supported_channel_masks[0] = AUDIO_CHANNEL_OUT_MONO;
-    out->channel_mask = AUDIO_CHANNEL_OUT_MONO;
+    //FIXME: add support for MONO stream configuration when audioflinger mixer supports it
+    out->supported_channel_masks[0] = AUDIO_CHANNEL_OUT_STEREO;
+    out->channel_mask = AUDIO_CHANNEL_OUT_STEREO;
+    out->config.rate = out->sample_rate;
 
+    ALOGV("%s: mode=%d, usecase id=%d", __func__, adev->mode, out->usecase);
     return 0;
 }
-#endif
-
diff --git a/hal/voice_extn/voice_extn.h b/hal/voice_extn/voice_extn.h
index f35344f..5d1cac3 100644
--- a/hal/voice_extn/voice_extn.h
+++ b/hal/voice_extn/voice_extn.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014, 2016-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2013-2014, 2016-2018, The Linux Foundation. All rights reserved.
  * Not a contribution.
  *
  * Copyright (C) 2013 The Android Open Source Project
@@ -101,13 +101,8 @@
 }
 #endif
 
-#ifdef INCALL_MUSIC_ENABLED
 int voice_extn_check_and_set_incall_music_usecase(struct audio_device *adev,
                                                   struct stream_out *out);
-#else
-#define voice_extn_check_and_set_incall_music_usecase(adev, out) -ENOSYS
-#endif
-
 #ifdef COMPRESS_VOIP_ENABLED
 int voice_extn_compress_voip_close_output_stream(struct audio_stream *stream);
 int voice_extn_compress_voip_open_output_stream(struct stream_out *out);