diff --git a/hal/Android.mk b/hal/Android.mk
index 5fb3322..d5aa190 100644
--- a/hal/Android.mk
+++ b/hal/Android.mk
@@ -336,6 +336,11 @@
     LOCAL_SHARED_LIBRARIES += vendor.qti.hardware.audiohalext@1.0
 endif
 
+ifeq ($(strip $(AUDIO_FEATURE_ELLIPTIC_ULTRASOUND_SUPPORT)),true)
+    LOCAL_CFLAGS += -DELLIPTIC_ULTRASOUND_ENABLED
+    LOCAL_SRC_FILES += audio_extn/ultrasound.c
+endif
+
 LOCAL_CFLAGS += -D_GNU_SOURCE
 LOCAL_CFLAGS += -Wall -Werror
 
diff --git a/hal/audio_extn/ultrasound.c b/hal/audio_extn/ultrasound.c
new file mode 100644
index 0000000..1199e22
--- /dev/null
+++ b/hal/audio_extn/ultrasound.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright (c) 2017-2018 The LineageOS Project
+ * Copyright (c) 2017 Balázs Triszka <balika011@protonmail.ch>
+ *
+ * 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.
+ */
+
+#define LOG_TAG "ultrasound"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <cutils/log.h>
+#include "audio_hw.h"
+#include "platform_api.h"
+#include <platform.h>
+#include "ultrasound.h"
+
+#define ULTRASOUND_CALIBRATION_FILE "/persist/audio/us_cal"
+#define ULTRASOUND_CALIBRATION_MIXER "Ultrasound Calibration Data"
+
+enum {
+    ULTRASOUND_STATUS_DEFAULT,
+    ULTRASOUND_STATUS_STARTED,
+    ULTRASOUND_STATUS_STOPPED,
+};
+
+struct pcm_config pcm_config_us = {
+    .channels = 1,
+    .rate = 96000,
+    .period_size = 1024,
+    .period_count = 2,
+    .format = PCM_FORMAT_S16_LE,
+};
+
+struct ultrasound_device {
+    struct pcm *rx_pcm, *tx_pcm;
+    int state;
+    struct audio_device *adev;
+};
+
+static struct ultrasound_device *us = NULL;
+
+void us_cal_load(void)
+{
+    FILE *f;
+    char buff[5] = {0}, us_cal[64];
+    struct mixer_ctl * ctl;
+    int rc;
+
+    f = fopen(ULTRASOUND_CALIBRATION_FILE, "r");
+    if (!f) {
+        ALOGE("%s: Cannot open calibration file: %s",
+                __func__, ULTRASOUND_CALIBRATION_FILE);
+        return;
+    }
+
+    for (size_t i = 0; i < sizeof(us_cal); i++) {
+        fread(buff, 1, sizeof(buff), f);
+        us_cal[i] = strtol(buff, 0, 16);
+    }
+    fclose(f);
+
+    ctl = mixer_get_ctl_by_name(us->adev->mixer, ULTRASOUND_CALIBRATION_MIXER);
+    if (!ctl) {
+        ALOGE("%s: Could not get ctl for mixer cmd - %s",
+                __func__, ULTRASOUND_CALIBRATION_MIXER);
+        return;
+    }
+
+    rc = mixer_ctl_set_array(ctl, us_cal, sizeof(us_cal));
+    if (rc < 0)
+        ALOGE("%s: Could not set ctl, error:%d ", __func__, rc);
+}
+
+int us_init(struct audio_device *adev)
+{
+    ALOGD("%s: enter", __func__);
+
+    if (us) {
+        ALOGI("%s: ultrasound has been initialized!", __func__);
+        return 0;
+    }
+
+    us = calloc(1, sizeof(struct ultrasound_device));
+    if (!us) {
+        ALOGE("%s: Out of memory!", __func__);
+        return -ENOMEM;
+    }
+
+    us->adev = adev;
+
+    us_cal_load();
+
+    ALOGD("%s: exit, status(0)", __func__);
+
+    return 0;
+}
+
+void us_deinit(void)
+{
+    ALOGD("%s: enter", __func__);
+
+    if (us) {
+        free(us);
+        us = NULL;
+    }
+
+    ALOGD("%s: exit", __func__);
+}
+
+int stop_us(void)
+{
+    struct audio_usecase *rx_usecase, *tx_usecase;
+    int rc = 0;
+
+    ALOGD("%s: enter usecase: ultrasound", __func__);
+
+    us->state = ULTRASOUND_STATUS_STOPPED;
+    if (us->rx_pcm) {
+        pcm_close(us->rx_pcm);
+        us->rx_pcm = NULL;
+    }
+
+    if (us->tx_pcm) {
+        pcm_close(us->tx_pcm);
+        us->tx_pcm = NULL;
+    }
+
+    rx_usecase = get_usecase_from_list(us->adev, USECASE_AUDIO_ULTRASOUND_RX);
+    if (!rx_usecase) {
+        ALOGE("%s: Could not find the usecase (%d) in the list",
+                __func__, USECASE_AUDIO_ULTRASOUND_RX);
+        rc = -EINVAL;
+    } else {
+        disable_audio_route(us->adev, rx_usecase);
+        disable_snd_device(us->adev, rx_usecase->out_snd_device);
+        list_remove(&rx_usecase->list);
+        free(rx_usecase);
+    }
+
+    tx_usecase = get_usecase_from_list(us->adev, USECASE_AUDIO_ULTRASOUND_TX);
+    if (!rx_usecase) {
+        ALOGE("%s: Could not find the usecase (%d) in the list",
+                __func__, USECASE_AUDIO_ULTRASOUND_TX);
+        rc = -EINVAL;
+    } else {
+        disable_audio_route(us->adev, tx_usecase);
+        disable_snd_device(us->adev, tx_usecase->in_snd_device);
+        list_remove(&tx_usecase->list);
+        free(tx_usecase);
+    }
+
+    ALOGD("%s: exit: status(%d)", __func__, rc);
+
+    return rc;
+}
+
+int us_start(void)
+{
+    int rx_device_id, tx_device_id;
+    struct audio_usecase *rx_usecase, *tx_usecase;
+
+    ALOGD("%s: enter", __func__);
+
+    if (!us || us->state == ULTRASOUND_STATUS_STARTED)
+        return -EPERM;
+
+    ALOGD("%s: enter usecase: ultrasound", __func__);
+    rx_device_id = platform_get_pcm_device_id(USECASE_AUDIO_ULTRASOUND_RX, PCM_PLAYBACK);
+    tx_device_id = platform_get_pcm_device_id(USECASE_AUDIO_ULTRASOUND_TX, PCM_CAPTURE);
+    if (rx_device_id < 0 || tx_device_id < 0) {
+        ALOGE("%s: Invalid PCM devices (rx: %d tx: %d) for the usecase(ultrasound)",
+                __func__, rx_device_id, tx_device_id);
+        stop_us();
+        ALOGE("%s: exit: status(%d)", __func__, -EIO);
+        return -EIO;
+    }
+
+    rx_usecase = calloc(1, sizeof(struct audio_usecase));
+    if (!rx_usecase) {
+        ALOGE("%s: Out of memory!", __func__);
+        return -ENOMEM;
+    }
+
+    rx_usecase->type = PCM_PLAYBACK;
+    rx_usecase->out_snd_device = SND_DEVICE_OUT_ULTRASOUND_HANDSET;
+    rx_usecase->id = USECASE_AUDIO_ULTRASOUND_RX;
+    list_add_tail(&us->adev->usecase_list, &rx_usecase->list);
+
+    enable_snd_device(us->adev, SND_DEVICE_OUT_ULTRASOUND_HANDSET);
+    enable_audio_route(us->adev, rx_usecase);
+    ALOGV("%s: Opening PCM playback device card_id(%d) device_id(%d)",
+            __func__, us->adev->snd_card, rx_device_id);
+    us->rx_pcm = pcm_open(us->adev->snd_card, rx_device_id, PCM_OUT, &pcm_config_us);
+    if (us->rx_pcm && !pcm_is_ready(us->rx_pcm)) {
+        ALOGE("%s: %s", __func__, pcm_get_error(us->rx_pcm));
+        stop_us();
+        ALOGE("%s: exit: status(%d)", __func__, -EIO);
+        return -EIO;
+    }
+
+    tx_usecase = calloc(1, sizeof(struct audio_usecase));
+    if (!tx_usecase) {
+        ALOGE("%s: Out of memory!", __func__);
+        return -ENOMEM;
+    }
+
+    tx_usecase->type = PCM_CAPTURE;
+    tx_usecase->in_snd_device = SND_DEVICE_IN_ULTRASOUND_MIC;
+    tx_usecase->id = USECASE_AUDIO_ULTRASOUND_TX;
+    list_add_tail(&us->adev->usecase_list, &tx_usecase->list);
+
+    enable_snd_device(us->adev, SND_DEVICE_IN_ULTRASOUND_MIC);
+    enable_audio_route(us->adev, tx_usecase);
+    ALOGV("%s: Opening PCM capture device card_id(%d) device_id(%d)",
+            __func__, us->adev->snd_card, tx_device_id);
+    us->tx_pcm = pcm_open(us->adev->snd_card, tx_device_id, PCM_IN, &pcm_config_us);
+    if (us->tx_pcm && !pcm_is_ready(us->tx_pcm)) {
+        ALOGD("%s: %s", __func__, pcm_get_error(us->tx_pcm));
+        stop_us();
+        ALOGE("%s: exit: status(%d)", __func__, -EIO);
+        return -EIO;
+    }
+
+    pcm_start(us->rx_pcm);
+    pcm_start(us->tx_pcm);
+    us->state = ULTRASOUND_STATUS_STARTED;
+
+    ALOGD("%s: exit, status(0)", __func__);
+
+    return 0;
+}
+
+int us_stop(void)
+{
+    ALOGD("%s: enter", __func__);
+
+    if (!us || us->state != ULTRASOUND_STATUS_STARTED)
+        return -EPERM;
+
+    stop_us();
+
+    return 0;
+}
diff --git a/hal/audio_extn/ultrasound.h b/hal/audio_extn/ultrasound.h
new file mode 100644
index 0000000..0bb24ca
--- /dev/null
+++ b/hal/audio_extn/ultrasound.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2017-2018 The LineageOS Project
+ * Copyright (c) 2017 Balázs Triszka <balika011@protonmail.ch>
+ *
+ * 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 ULTRASOUND_H
+#define ULTRASOUND_H
+
+#ifndef ELLIPTIC_ULTRASOUND_ENABLED
+#define us_init(adev) (0)
+#define us_deinit() (0)
+#define us_start() (0)
+#define us_stop() (0)
+#else
+int us_init(struct audio_device *adev);
+void us_deinit(void);
+int us_start(void);
+int us_stop(void);
+#endif
+
+#endif
diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index d6194cb..27e2fa3 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -75,6 +75,7 @@
 #include "audio_extn.h"
 #include "voice_extn.h"
 #include "ip_hdlr_intf.h"
+#include "ultrasound.h"
 
 #include "sound/compress_params.h"
 #include "sound/asound.h"
@@ -407,6 +408,10 @@
     [USECASE_AUDIO_PLAYBACK_NAV_GUIDANCE] = "nav-guidance-playback",
     [USECASE_AUDIO_PLAYBACK_PHONE] = "phone-playback",
     [USECASE_AUDIO_FM_TUNER_EXT] = "fm-tuner-ext",
+
+    /* For Elliptic Ultrasound proximity sensor */
+    [USECASE_AUDIO_ULTRASOUND_RX] = "ultrasound-rx",
+    [USECASE_AUDIO_ULTRASOUND_TX] = "ultrasound-tx",
 };
 
 static const audio_usecase_t offload_usecases[] = {
@@ -1139,6 +1144,9 @@
     audio_extn_utils_send_app_type_cfg(adev, usecase);
     if (audio_extn_is_maxx_audio_enabled())
         audio_extn_ma_set_device(usecase);
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+    if (usecase->id != USECASE_AUDIO_ULTRASOUND_TX)
+#endif
     audio_extn_utils_send_audio_calibration(adev, usecase);
     if ((usecase->type == PCM_PLAYBACK) && is_offload_usecase(usecase->id)) {
         out = usecase->stream.out;
@@ -1308,6 +1316,10 @@
                                         ST_EVENT_SND_DEVICE_BUSY);
         audio_extn_listen_update_device_status(snd_device,
                                         LISTEN_EVENT_SND_DEVICE_BUSY);
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+        if (snd_device != SND_DEVICE_OUT_ULTRASOUND_HANDSET &&
+            snd_device != SND_DEVICE_IN_ULTRASOUND_MIC)
+#endif
         if (platform_get_snd_device_acdb_id(snd_device) < 0) {
             audio_extn_sound_trigger_update_device_status(snd_device,
                                             ST_EVENT_SND_DEVICE_FREE);
@@ -1613,6 +1625,12 @@
               platform_get_snd_device_name(snd_device),
               platform_get_snd_device_name(usecase->out_snd_device),
               platform_check_backends_match(snd_device, usecase->out_snd_device));
+
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+        if (usecase->id == USECASE_AUDIO_ULTRASOUND_RX)
+            continue;
+#endif
+
         if ((usecase->type != PCM_CAPTURE) && (usecase != uc_info) &&
                 (usecase->type != PCM_PASSTHROUGH)) {
             uc_derive_snd_device = derive_playback_snd_device(adev->platform,
@@ -1758,6 +1776,12 @@
         /*
          * TODO: Enhance below condition to handle BT sco/USB multi recording
          */
+
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+        if (usecase->id == USECASE_AUDIO_ULTRASOUND_TX)
+            continue;
+#endif
+
         if (usecase->type != PCM_PLAYBACK &&
                 usecase != uc_info &&
                 (usecase->in_snd_device != snd_device || force_routing) &&
@@ -8348,6 +8372,15 @@
         }
     }
 
+    ret = str_parms_get_int(parms, "ultrasound-sensor", &val);
+    if (ret >= 0) {
+        if (val == 1) {
+            us_start();
+        } else {
+            us_stop();
+        }
+    }
+
     audio_extn_set_parameters(adev, parms);
 done:
     str_parms_destroy(parms);
@@ -9371,6 +9404,9 @@
         free(device);
         adev = NULL;
     }
+
+    us_deinit();
+
     pthread_mutex_unlock(&adev_init_lock);
     enable_gcov();
     return 0;
@@ -9750,6 +9786,9 @@
     adev->vr_audio_mode_enabled = false;
 
     audio_extn_ds2_enable(adev);
+
+    us_init(adev);
+
     *device = &adev->device.common;
 
     if (k_enable_extended_precision)
diff --git a/hal/audio_hw.h b/hal/audio_hw.h
index 9b7bf5b..dc62f83 100644
--- a/hal/audio_hw.h
+++ b/hal/audio_hw.h
@@ -230,6 +230,11 @@
 
     /*Audio FM Tuner usecase*/
     USECASE_AUDIO_FM_TUNER_EXT,
+
+    /* Elliptic Ultrasound */
+    USECASE_AUDIO_ULTRASOUND_RX,
+    USECASE_AUDIO_ULTRASOUND_TX,
+
     AUDIO_USECASE_MAX
 };
 
diff --git a/hal/msm8974/platform.c b/hal/msm8974/platform.c
index 7d63d17..4a1d49c 100644
--- a/hal/msm8974/platform.c
+++ b/hal/msm8974/platform.c
@@ -482,6 +482,9 @@
     [USECASE_AUDIO_PLAYBACK_PHONE] = {PHONE_PCM_DEVICE,
                                       PHONE_PCM_DEVICE},
     [USECASE_AUDIO_FM_TUNER_EXT] = {-1, -1},
+    [USECASE_AUDIO_ULTRASOUND_RX] = {ULTRASOUND_PCM_DEVICE, -1},
+    [USECASE_AUDIO_ULTRASOUND_TX] = {-1, ULTRASOUND_PCM_DEVICE},
+
 };
 
 /* Array to store sound devices */
@@ -584,6 +587,7 @@
     [SND_DEVICE_OUT_BUS_SYS] = "bus-speaker",
     [SND_DEVICE_OUT_BUS_NAV] = "bus-speaker",
     [SND_DEVICE_OUT_BUS_PHN] = "bus-speaker",
+    [SND_DEVICE_OUT_ULTRASOUND_HANDSET] = "ultrasound-handset",
 
     /* Capture sound devices */
     [SND_DEVICE_IN_HANDSET_MIC] = "handset-mic",
@@ -722,6 +726,7 @@
     [SND_DEVICE_IN_HANDSET_QMIC_AND_EC_REF_LOOPBACK] = "handset-qmic-and-ec-ref-loopback",
     [SND_DEVICE_IN_HANDSET_6MIC_AND_EC_REF_LOOPBACK] = "handset-6mic-and-ec-ref-loopback",
     [SND_DEVICE_IN_HANDSET_8MIC_AND_EC_REF_LOOPBACK] = "handset-8mic-and-ec-ref-loopback",
+    [SND_DEVICE_IN_ULTRASOUND_MIC] = "ultrasound-mic",
 };
 
 // Platform specific backend bit width table
@@ -1281,6 +1286,8 @@
     {TO_NAME_INDEX(USECASE_AUDIO_PLAYBACK_SYS_NOTIFICATION)},
     {TO_NAME_INDEX(USECASE_AUDIO_PLAYBACK_NAV_GUIDANCE)},
     {TO_NAME_INDEX(USECASE_AUDIO_PLAYBACK_PHONE)},
+    {TO_NAME_INDEX(USECASE_AUDIO_ULTRASOUND_RX)},
+    {TO_NAME_INDEX(USECASE_AUDIO_ULTRASOUND_TX)},
 };
 
 static const struct name_to_index usecase_type_index[USECASE_TYPE_MAX] = {
@@ -1748,7 +1755,11 @@
             usecase = node_to_item(node, struct audio_usecase, list);
 
             if (usecase != NULL && usecase->stream.out &&
-                                   usecase->type == PCM_PLAYBACK) {
+                                   usecase->type == PCM_PLAYBACK
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+                && usecase->id != USECASE_AUDIO_ULTRASOUND_RX
+#endif
+                ) {
                 int new_snd_device[2] = {0};
                 int i, num_devices = 1;
 
@@ -2230,6 +2241,7 @@
     hw_interface_table[SND_DEVICE_OUT_BUS_SYS] = strdup("TERT_TDM_RX_0");
     hw_interface_table[SND_DEVICE_OUT_BUS_NAV] = strdup("TERT_TDM_RX_1");
     hw_interface_table[SND_DEVICE_OUT_BUS_PHN] = strdup("TERT_TDM_RX_2");
+    hw_interface_table[SND_DEVICE_OUT_ULTRASOUND_HANDSET] = strdup("SLIMBUS_0_RX");
     hw_interface_table[SND_DEVICE_IN_HANDSET_MIC] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_HANDSET_MIC_SB] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_HANDSET_MIC_EXTERNAL] = strdup("SLIMBUS_0_TX");
@@ -2357,6 +2369,8 @@
     hw_interface_table[SND_DEVICE_IN_CAMCORDER_SELFIE_PORTRAIT] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_VOICE_HEARING_AID] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_BUS] = strdup("TERT_TDM_TX_0");
+    hw_interface_table[SND_DEVICE_IN_ULTRASOUND_MIC] = strdup("SLIMBUS_0_TX");
+
     my_data->max_mic_count = PLATFORM_DEFAULT_MIC_COUNT;
 
      /*remove ALAC & APE from DSP decoder list based on software decoder availability*/
@@ -10598,6 +10612,9 @@
 
     list_for_each(node, &adev->usecase_list) {
         usecase = node_to_item(node, struct audio_usecase, list);
+#ifdef ELLIPTIC_ULTRASOUND_ENABLED
+        if (usecase->id != USECASE_AUDIO_ULTRASOUND_RX)
+#endif
         if (usecase->stream.out && usecase->type == PCM_PLAYBACK &&
                 usecase->stream.out->devices & AUDIO_DEVICE_OUT_SPEAKER) {
             /*
diff --git a/hal/msm8974/platform.h b/hal/msm8974/platform.h
index f638b44..e3dfe84 100644
--- a/hal/msm8974/platform.h
+++ b/hal/msm8974/platform.h
@@ -181,6 +181,7 @@
     SND_DEVICE_OUT_BUS_SYS,
     SND_DEVICE_OUT_BUS_NAV,
     SND_DEVICE_OUT_BUS_PHN,
+    SND_DEVICE_OUT_ULTRASOUND_HANDSET,
     SND_DEVICE_OUT_END,
 
     /*
@@ -323,6 +324,7 @@
     SND_DEVICE_IN_HANDSET_QMIC_AND_EC_REF_LOOPBACK,
     SND_DEVICE_IN_HANDSET_6MIC_AND_EC_REF_LOOPBACK,
     SND_DEVICE_IN_HANDSET_8MIC_AND_EC_REF_LOOPBACK,
+    SND_DEVICE_IN_ULTRASOUND_MIC,
     SND_DEVICE_IN_END,
 
     SND_DEVICE_MAX = SND_DEVICE_IN_END,
@@ -623,6 +625,8 @@
 #define AFE_PROXY_PLAYBACK_PCM_DEVICE 7
 #define AFE_PROXY_RECORD_PCM_DEVICE 8
 
+#define ULTRASOUND_PCM_DEVICE 10
+
 #ifdef PLATFORM_MSM8x26
 #ifdef EXTERNAL_BT_SUPPORTED
 #define HFP_SCO_RX 10 // AUXPCM Hostless