diff --git a/hal/audio_hal_plugin.h b/hal/audio_hal_plugin.h
new file mode 100644
index 0000000..9b20d3c
--- /dev/null
+++ b/hal/audio_hal_plugin.h
@@ -0,0 +1,375 @@
+/* Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above
+ *     copyright notice, this list of conditions and the following
+ *     disclaimer in the documentation and/or other materials provided
+ *     with the distribution.
+ *   * Neither the name of The Linux Foundation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef AUDIO_HAL_PLUGIN_H
+#define AUDIO_HAL_PLUGIN_H
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+#include <audio_hw.h>
+
+#define AUDIO_HAL_PLUGIN_EOK (0)
+#define AUDIO_HAL_PLUGIN_EFAIL (-1) /**< Undefined error */
+#define AUDIO_HAL_PLUGIN_ENOMEM (-2) /**< Out of memory */
+#define AUDIO_HAL_PLUGIN_EINVAL (-3) /**< Invalid argument */
+#define AUDIO_HAL_PLUGIN_EBUSY (-4) /**< Plugin driver is busy */
+#define AUDIO_HAL_PLUGIN_ENODEV (-5) /**< No device */
+#define AUDIO_HAL_PLUGIN_EALREADY (-6) /**< Already done */
+
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_MSG_TYPE     "ext_hw_plugin_msg_type"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_UC           "ext_hw_plugin_usecase"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_SND_DEVICE   "ext_hw_plugin_snd_device"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_DIRECTION    "ext_hw_plugin_direction"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_CMASK        "ext_hw_plugin_channel_mask"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_GAIN         "ext_hw_plugin_gain"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_MUTE_FLAG    "ext_hw_plugin_mute_flag"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_FADE         "ext_hw_plugin_fade"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_BALANCE      "ext_hw_plugin_balance"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_BMT_FTYPE    "ext_hw_plugin_bmt_filter_type"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_BMT_FLAG     "ext_hw_plugin_bmt_flag"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_BMT_VAL      "ext_hw_plugin_bmt_value"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_EQ_FLAG      "ext_hw_plugin_eq_flag"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_EQ_ID        "ext_hw_plugin_eq_id"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_EQ_NUM_BANDS "ext_hw_plugin_eq_num_bands"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_EQ_BAND_DATA "ext_hw_plugin_eq_band_data"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_TUNNEL_SIZE  "ext_hw_plugin_tunnel_size"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_TUNNEL_DATA  "ext_hw_plugin_tunnel_data"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_GETPARAM_RESULT "ext_hw_plugin_getparam_result"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_GETPARAM_DATA "ext_hw_plugin_getparam_data"
+#define AUDIO_PARAMETER_KEY_EXT_HW_PLUGIN_TUNNEL_GET_SIZE "ext_hw_plugin_tunnel_get_size"
+/**
+ * Type of audio hal plug-in messages
+ */
+typedef enum
+{
+    AUDIO_HAL_PLUGIN_MSG_INVALID = 0,
+    AUDIO_HAL_PLUGIN_MSG_CODEC_ENABLE, /**< setup codec routing path */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_DISABLE, /**< tear down routing path */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_VOLUME, /**< set volume */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_MUTE, /**< mute/unmute control */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_FADE, /**< fade out control */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_BALANCE, /**< left/right balance control */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_BMT, /**< base/mid/treble control */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_EQ, /**< EQ control */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_TUNNEL_CMD, /**< pass through cmds */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_VOLUME, /**< get volume params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_FADE, /**< get fade params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_BALANCE, /**< get balance params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_BMT, /**< get bmt params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_EQ, /**< get EQ params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_EQ_SUBBANDS, /**< get EQ subbands params */
+    AUDIO_HAL_PLUGIN_MSG_CODEC_TUNNEL_GET_CMD, /**< pass through get cmds */
+    AUDIO_HAL_PLUGIN_MSG_MAX
+} audio_hal_plugin_msg_type_t;
+
+/**
+ * Type of audio hal plug-in use cases
+ */
+typedef enum
+{
+    AUDIO_HAL_PLUGIN_USECASE_INVALID = -1,
+    AUDIO_HAL_PLUGIN_USECASE_DEFAULT_PLAYBACK = 0,
+    AUDIO_HAL_PLUGIN_USECASE_DEFAULT_CAPTURE,
+    AUDIO_HAL_PLUGIN_USECASE_DRIVER_SIDE_PLAYBACK,
+    AUDIO_HAL_PLUGIN_USECASE_HFP_VOICE_CALL,
+    AUDIO_HAL_PLUGIN_USECASE_CS_VOICE_CALL,
+    AUDIO_HAL_PLUGIN_USECASE_FM_TUNER,
+    AUDIO_HAL_PLUGIN_USECASE_ICC,
+    AUDIO_HAL_PLUGIN_USECASE_EC_CAPTURE,
+    AUDIO_HAL_PLUGIN_USECASE_EC_REF_CAPTURE,
+    AUDIO_HAL_PLUGIN_USECASE_ANC,
+    AUDIO_HAL_PLUGIN_USECASE_LINE_IN_PASSTHROUGH,
+    AUDIO_HAL_PLUGIN_USECASE_HDMI_IN_PASSTHROUGH,
+    AUDIO_HAL_PLUGIN_USECASE_PHONE_PLAYBACK,
+    AUDIO_HAL_PLUGIN_USECASE_MAX
+} audio_hal_plugin_usecase_type_t;
+
+/**
+ * Type of audio hal plug-in direction used in set_param
+ */
+typedef enum
+{
+    AUDIO_HAL_PLUGIN_DIRECTION_INVALID = -1,
+    AUDIO_HAL_PLUGIN_DIRECTION_PLAYBACK = 0,
+    AUDIO_HAL_PLUGIN_DIRECTION_CAPTURE,
+    AUDIO_HAL_PLUGIN_DIRECTION_MAX
+} audio_hal_plugin_direction_type_t;
+
+/**
+ * Type of query status mask
+ */
+#define QUERY_VALUE_VALID            (0x0)
+#define QUERY_VALUE_NOT_SUPPORTED    (0x1)
+#define QUERY_VALUE_NOT_SET          (0x2)
+
+/**
+ * Type of signed 32-bit bounded value used in get_param
+ */
+typedef struct audio_hal_plugin_bint32
+{
+    uint32_t query_status_mask; /**< status of returned actual value */
+    int32_t value; /**< actual value */
+    int32_t min; /**< minimum for value */
+    int32_t max; /**< maximum for value */
+} audio_hal_plugin_bint32_t;
+
+/**
+ * Type of unsigned 32-bit bounded value used in get_param
+ */
+typedef struct audio_hal_plugin_buint32
+{
+    uint32_t query_status_mask; /**< status of returned actual value */
+    uint32_t value; /**< actual value */
+    uint32_t min; /**< minimum for value */
+    uint32_t max; /**< maximum for value */
+} audio_hal_plugin_buint32_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_ENABLE message
+ */
+typedef struct audio_hal_plugin_codec_enable
+{
+    snd_device_t snd_dev;  /**< Requested endpoint device to be enabled. @enum: SND_DEVICE_XXX */
+    audio_hal_plugin_usecase_type_t usecase;
+            /**< Requested use case. @enum: AUDIO_HAL_PLUGIN_USECASE_XXX */
+    uint32_t sample_rate;  /**< Requested sample rate for the endpoint device */
+    uint32_t bit_width;  /**< Requested bit width per sample for the endpoint device */
+    uint32_t num_chs;  /**< Requested number of channels for the endpoint device */
+} audio_hal_plugin_codec_enable_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_DISABLE message
+ */
+typedef struct audio_hal_plugin_codec_disable
+{
+    snd_device_t snd_dev; /**< Requested the endpoint device to be disabled */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+} audio_hal_plugin_codec_disable_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_VOLUME message
+ */
+typedef struct audio_hal_plugin_codec_set_pp_vol
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_channel_mask_t ch_mask; /**< Requested audio channel mask */
+    uint32_t gain; /**< The requested volume setting. */
+} audio_hal_plugin_codec_set_pp_vol_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_MUTE message
+ */
+typedef struct audio_hal_plugin_codec_set_pp_mute
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_channel_mask_t ch_mask; /**< Requested audio channel mask */
+    bool flag; /**< Enable/Disable mute flag. 1: mute, 0: unmute */
+} audio_hal_plugin_codec_set_pp_mute_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_FADE message
+ */
+typedef struct audio_hal_plugin_codec_set_pp_fade
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    int32_t fade; /**< The requested fade configuration. */
+} audio_hal_plugin_codec_set_pp_fade_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_BALANCE message
+ */
+typedef struct audio_hal_plugin_codec_set_pp_balance
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    int32_t balance; /**< The requested balance configuration. */
+} audio_hal_plugin_codec_set_pp_balance_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_BMT message
+ */
+typedef enum
+{
+    AUDIO_HAL_PLUGIN_CODEC_PP_FILTER_TYPE_INVALID = 0,
+    AUDIO_HAL_PLUGIN_CODEC_PP_FILTER_TYPE_BASS,
+    AUDIO_HAL_PLUGIN_CODEC_PP_FILTER_TYPE_MID,
+    AUDIO_HAL_PLUGIN_CODEC_PP_FILTER_TYPE_TREBLE,
+    AUDIO_HAL_PLUGIN_CODEC_PP_FILTER_TYPE_MAX
+} audio_hal_plugin_codec_pp_filter_type_t;
+
+typedef struct audio_hal_plugin_codec_set_pp_bmt
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_hal_plugin_codec_pp_filter_type_t filter_type; /**< Requested filter type */
+    bool enable_flag; /**< Enable flag. 0 - Disable, 1 - Enable */
+    int32_t value; /**< Requested value to be set */
+} audio_hal_plugin_codec_set_pp_bmt_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_SET_PP_EQ message
+ */
+typedef struct audio_hal_plugin_codec_pp_eq_subband
+{
+    uint32_t band_idx; /**< Band index. Supported value: 0 to (num_bands - 1) */
+    uint32_t center_freq; /**< Filter band center frequency in millihertz */
+    int32_t band_level; /**< Filter band gain in millibels */
+} audio_hal_plugin_codec_pp_eq_subband_t;
+
+typedef struct audio_hal_plugin_codec_set_pp_eq
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    bool enable_flag; /**< Enable flag. 0 - Disable, 1 - Enable */
+    int32_t preset_id; /**< Specify to use either pre-defined preset EQ or
+                                        user-customized equalizers:
+                                        -1      - custom equalizer speficied through 'bands' struct
+                                        0 to N - pre-defined preset EQ index: ROCK/JAZZ/POP, etc */
+    uint32_t num_bands; /**< Number of EQ subbands when a custom preset_id is selected */
+    audio_hal_plugin_codec_pp_eq_subband_t *bands; /**< Equalizer sub-band struct list */
+} audio_hal_plugin_codec_set_pp_eq_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_VOLUME message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_vol
+{
+    snd_device_t snd_dev; /**< Requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_channel_mask_t ch_mask; /**< Requested audio channel mask */
+    audio_hal_plugin_buint32_t ret_gain; /**< Returned volume range and value */
+} audio_hal_plugin_codec_get_pp_vol_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_FADE message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_fade
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_hal_plugin_bint32_t ret_fade; /**< Returned fade range and value. */
+} audio_hal_plugin_codec_get_pp_fade_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_BALANCE message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_balance
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_hal_plugin_bint32_t ret_balance; /**< Returned balance range and value. */
+} audio_hal_plugin_codec_get_pp_balance_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_BMT message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_bmt
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_hal_plugin_codec_pp_filter_type_t filter_type; /**< Requested filter type */
+    audio_hal_plugin_bint32_t ret_value; /**< Returned range and value */
+} audio_hal_plugin_codec_get_pp_bmt_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_EQ message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_eq
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    audio_hal_plugin_bint32_t ret_preset_id; /**< Returned preset id
+                                        -1      - custom equalizer speficied through 'bands' struct
+                                        0 to N - pre-defined preset EQ index: ROCK/JAZZ/POP, etc */
+    uint32_t ret_num_bands; /**< Returned number of EQ subbands supported
+                                          when a custom preset_id is selected */
+} audio_hal_plugin_codec_get_pp_eq_t;
+
+/**
+ * Eq_subband struct used in the following payload
+ */
+typedef struct audio_hal_plugin_pp_eq_subband_binfo
+{
+    audio_hal_plugin_buint32_t ret_center_freq; /**< Returned band center frequency range
+                                                                                            and value in millihertz */
+    audio_hal_plugin_bint32_t ret_band_level; /**< Returned band gain range and value in millibels */
+} audio_hal_plugin_pp_eq_subband_binfo_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_GET_PP_EQ_SUBBANDS message
+ */
+typedef struct audio_hal_plugin_codec_get_pp_eq_subbands
+{
+    snd_device_t snd_dev; /**< The requested endpoint device */
+    audio_hal_plugin_usecase_type_t usecase; /**< Requested use case */
+    uint32_t num_bands; /**< number of EQ subbands supported for custom eq
+                                          returned from get_pp_eq query */
+    audio_hal_plugin_pp_eq_subband_binfo_t *ret_bands; /**< Returned subband info list */
+} audio_hal_plugin_codec_get_pp_eq_subbands_t;
+
+/**
+ * Payload of AUDIO_HAL_PLUGIN_MSG_CODEC_TUNNEL_GET_CMD message
+ */
+typedef struct audio_hal_plugin_codec_tunnel_get
+{
+    int32_t *param_data; /**< Request param data from client */
+    uint32_t param_size; /**< Request 32-bit data size from client */
+    uint32_t size_to_get; /**< Expected 32-bit data size to get from cleint */
+    int32_t *ret_data; /**< Returned data */
+    uint32_t ret_size; /**< Returned 32-bit data size */
+} audio_hal_plugin_codec_tunnel_get_t;
+
+/**
+ * Initialize the audio hal plug-in module and underlying hw driver
+ * One time call at audio hal boot up time
+ */
+int32_t audio_hal_plugin_init (void);
+
+/**
+ * De-Initialize the audio hal plug-in module and underlying hw driver
+ * One time call when audio hal get unloaded from system
+ */
+int32_t audio_hal_plugin_deinit (void);
+
+/**
+ * Function to invoke the underlying HW driver realizing the functionality for a given use case.
+ */
+int32_t audio_hal_plugin_send_msg (
+             audio_hal_plugin_msg_type_t msg,
+             void * payload, uint32_t payload_size);
+
+#if defined(__cplusplus)
+}  /* extern "C" */
+#endif
+
+#endif