audio: porting MAXXAUDIO

  - use effect module to monitor stream's volume
  - the control(maxxaudio) monitors active device and
    changed volume from HAL, and send audio calibration
    to acdb via acdb_loader.
  - support specific USB headset

  Enabled function:
  - LR channels swap
  - load external tuning table for volume preset feature

Bug: 74360112
Test: manual effect test, usb headset test
Change-Id: I9b35436d6abebcfa250beb4857dfa0be9248f2b5
diff --git a/post_proc/Android.mk b/post_proc/Android.mk
index c31b769..dc0e260 100644
--- a/post_proc/Android.mk
+++ b/post_proc/Android.mk
@@ -73,3 +73,36 @@
 include $(BUILD_SHARED_LIBRARY)
 
 endif
+
+################################################################################
+ifeq ($(strip $(AUDIO_FEATURE_ENABLED_MAXX_AUDIO)), true)
+
+include $(CLEAR_VARS)
+
+LOCAL_CFLAGS := -D HAL_LIB_NAME=\"audio.primary."$(TARGET_BOARD_PLATFORM)".so\"
+
+LOCAL_SRC_FILES:= \
+	ma_listener.c
+
+LOCAL_CFLAGS += $(qcom_post_proc_common_cflags)
+
+LOCAL_SHARED_LIBRARIES := \
+	libcutils \
+	liblog \
+	libdl
+
+LOCAL_MODULE_RELATIVE_PATH := soundfx
+LOCAL_MODULE:= libmalistener
+LOCAL_MODULE_OWNER := google
+LOCAL_PROPRIETARY_MODULE := true
+
+LOCAL_C_INCLUDES := \
+	hardware/qcom/audio/hal \
+	system/media/audio/include/system \
+	$(call include-path-for, audio-effects)
+
+LOCAL_HEADER_LIBRARIES += libhardware_headers
+LOCAL_HEADER_LIBRARIES += libsystem_headers
+include $(BUILD_SHARED_LIBRARY)
+
+endif
diff --git a/post_proc/ma_listener.c b/post_proc/ma_listener.c
new file mode 100644
index 0000000..8e57db1
--- /dev/null
+++ b/post_proc/ma_listener.c
@@ -0,0 +1,627 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * 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 "ma_listener"
+/*#define LOG_NDEBUG 0*/
+
+#include <stdlib.h>
+#include <dlfcn.h>
+#include <math.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <cutils/list.h>
+#include <cutils/log.h>
+#include <hardware/audio_effect.h>
+#include <audio-base.h>
+
+#define MA_FLAG ( EFFECT_FLAG_TYPE_INSERT | \
+                   EFFECT_FLAG_VOLUME_IND | \
+                   EFFECT_FLAG_DEVICE_IND | \
+                   EFFECT_FLAG_OFFLOAD_SUPPORTED | \
+                   EFFECT_FLAG_NO_PROCESS)
+
+#define PRINT_STREAM_TYPE(i) ALOGV("descriptor found and is of stream type %s ",\
+                                                            i == AUDIO_STREAM_MUSIC ? "MUSIC": \
+                                                            i == AUDIO_STREAM_RING ? "RING": \
+                                                            i == AUDIO_STREAM_ALARM ? "ALARM": \
+                                                            i == AUDIO_STREAM_VOICE_CALL ? "Voice_call": \
+                                                            i == AUDIO_STREAM_SYSTEM ? "SYSTEM":       \
+                                                            i == AUDIO_STREAM_NOTIFICATION ? "Notification":\
+                                                            "--INVALID--"); \
+
+#define MA_SET_STATE "audio_hw_send_ma_parameter"
+#define HAL_VENDOR_PATH "/vendor/lib/hw"
+
+enum {
+    MA_LISTENER_STATE_UNINITIALIZED,
+    MA_LISTENER_STATE_INITIALIZED,
+    MA_LISTENER_STATE_ACTIVE,
+};
+
+typedef struct ma_listener_context_s ma_listener_context_t;
+static const struct effect_interface_s effect_interface;
+
+struct ma_state {
+    float vol;
+    bool active;
+};
+
+static const audio_stream_type_t MIN_STREAM_TYPES = AUDIO_STREAM_VOICE_CALL;
+static const audio_stream_type_t MAX_STREAM_TYPES = AUDIO_STREAM_NOTIFICATION;
+static struct ma_state g_cur_state[MAX_STREAM_TYPES];
+
+struct ma_listener_context_s {
+    const struct effect_interface_s *itfe;
+    struct listnode effect_list_node;
+    effect_config_t config;
+    const effect_descriptor_t *desc;
+    uint32_t stream_type;
+    uint32_t session_id;
+    uint32_t state;
+    uint32_t dev_id;
+    float left_vol;
+    float right_vol;
+};
+
+/* voice UUID: 4ece09c2-3728-11e8-a9f9-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_voice_descriptor = {
+    { 0x46f924ed, 0x25c3, 0x4272, 0x85b1, { 0x41, 0x78, 0x3f, 0x0d, 0xc6, 0x38 } },  // type
+    { 0x4ece09c2, 0x3728, 0x11e8, 0xa9f9, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for Voice",
+    "The Android Open Source Project",
+};
+
+/* system UUID: 4f705ff6-3728-11e8-a0c6-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_system_descriptor = {
+    { 0x8bd0f979, 0x5266, 0x4791, 0x9213, { 0x11, 0x3a, 0xbc, 0xf7, 0xd3, 0xdc } },  // type
+    { 0x4f705ff6, 0x3728, 0x11e8, 0xa0c6, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for System",
+    "The Android Open Source Project",
+};
+
+/* ring UUID: 4fd6e5c8-3728-11e8-8303-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_ring_descriptor = {
+    { 0x5380692a, 0x872e, 0x4697, 0x8e38, { 0xcd, 0xd1, 0x09, 0xf6, 0xcb, 0x87 } },  // type
+    { 0x4fd6e5c8, 0x3728, 0x11e8, 0x8303, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for Ring",
+    "The Android Open Source Project",
+};
+/* music UUID: 5036194e-3728-11e8-8db9-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_music_descriptor = {
+    { 0x3a3a19b2, 0x62b1, 0x4785, 0xb55e, { 0xb2, 0x8f, 0xd4, 0x1b, 0x83, 0x58 } },  // type
+    { 0x5036194e, 0x3728, 0x11e8, 0x8db9, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for Music",
+    "The Android Open Source Project",
+};
+/* alarm UUID: 50b9f084-3728-11e8-9225-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_alarm_descriptor = {
+    { 0x8d08d30f, 0xb4c3, 0x4600, 0x8f99, { 0xfc, 0xbb, 0x5d, 0x05, 0x8b, 0x60 } },  // type
+    { 0x50b9f084, 0x3728, 0x11e8, 0x9225, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for Alarm",
+    "The Android Open Source Project",
+};
+/* notification UUID: 50fe4d56-3728-11e8-ac73-fc4dd4486b6d */
+const effect_descriptor_t ma_listener_notification_descriptor = {
+    { 0x513d09f5, 0xae7f, 0x483d, 0x922a, { 0x5c, 0x72, 0xc5, 0xe5, 0x68, 0x4c } },  // type
+    { 0x50fe4d56, 0x3728, 0x11e8, 0xac73, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
+    EFFECT_CONTROL_API_VERSION,
+    MA_FLAG,
+    0, /* TODO */
+    1,
+    "MAXXAUDIO listener for Notification",
+    "The Android Open Source Project",
+};
+
+static const effect_descriptor_t *descriptors[] = {
+    &ma_listener_voice_descriptor,
+    &ma_listener_system_descriptor,
+    &ma_listener_ring_descriptor,
+    &ma_listener_music_descriptor,
+    &ma_listener_alarm_descriptor,
+    &ma_listener_notification_descriptor,
+    NULL,
+};
+
+/* function of sending state to HAL */
+static bool (*send_ma_parameter)(int, float, bool);
+
+static int init_state = -1;
+pthread_once_t once = PTHREAD_ONCE_INIT;
+
+struct listnode ma_effect_list;
+pthread_mutex_t ma_listner_init_lock;
+
+/*
+ *  Local functions
+ */
+static inline bool valid_dev_in_context(struct ma_listener_context_s *context)
+{
+    /* check device */
+    if ((context->dev_id & AUDIO_DEVICE_OUT_SPEAKER) ||
+        (context->dev_id & AUDIO_DEVICE_OUT_SPEAKER_SAFE) ||
+        /* TODO: it should be dynamic if hybird split A2SP is implemented. */
+        (context->dev_id & AUDIO_DEVICE_OUT_ALL_A2DP) ||
+        (context->dev_id & AUDIO_DEVICE_OUT_ALL_USB)) {
+        return true;
+    }
+
+    return false;
+}
+
+static void check_and_set_ma_parameter(uint32_t stream_type)
+{
+    bool active = false;
+    float temp_vol = 0.0;
+    float max_vol = 0.0;
+    struct listnode *node = NULL;
+    ma_listener_context_t *context = NULL;
+
+    ALOGV("%s .. called ..", __func__);
+    // get maximum volume for the active session with same strem type
+    list_for_each(node, &ma_effect_list) {
+        context = node_to_item(node, struct ma_listener_context_s, effect_list_node);
+        if (context->stream_type == stream_type &&
+            valid_dev_in_context(context)) {
+            if (context->state == MA_LISTENER_STATE_ACTIVE) {
+                active = true;
+                temp_vol = fmax(context->left_vol, context->right_vol);
+                if (max_vol < temp_vol)
+                    max_vol = temp_vol;
+                ALOGV("%s: check session(%d) volume(%f) for stream(%d)",
+                       __func__, context->session_id, temp_vol, stream_type);
+            }
+        }
+    }
+
+    // check volume
+    if (max_vol < 0.0) max_vol = 0;
+    else if (max_vol > 1.0) max_vol = 1.0;
+
+    if (send_ma_parameter != NULL &&
+        (g_cur_state[stream_type].vol != max_vol ||
+         g_cur_state[stream_type].active != active)) {
+
+        ALOGV("%s: set stream(%d) active(%s->%s) volume(%f->%f)",
+              __func__, stream_type,
+              g_cur_state[stream_type].active ? "T" : "F", active ? "T" : "F",
+              g_cur_state[stream_type].vol, max_vol);
+
+        // update changes to hal
+        send_ma_parameter(stream_type, max_vol, active);
+        g_cur_state[stream_type].vol = max_vol;
+        g_cur_state[stream_type].active = active;
+    }
+
+    return;
+}
+
+/*
+ * Effect Control Interface Implementation
+ */
+static int ma_effect_command(effect_handle_t self,
+                              uint32_t cmd_code, uint32_t cmd_size,
+                              void *p_cmd_data, uint32_t *reply_size,
+                              void *p_reply_data)
+{
+    ma_listener_context_t *context = (ma_listener_context_t *)self;
+    int status = 0;
+
+    ALOGV("%s .. called ..", __func__);
+    pthread_mutex_lock(&ma_listner_init_lock);
+
+    if (context == NULL || context->state == MA_LISTENER_STATE_UNINITIALIZED) {
+        ALOGE("%s: %s is NULL", __func__, (context == NULL) ?
+              "context" : "context->state");
+        status = -EINVAL;
+        goto exit;
+    }
+
+    switch (cmd_code) {
+    case EFFECT_CMD_INIT:
+        ALOGV("%s :: cmd called EFFECT_CMD_INIT", __func__);
+        if (p_reply_data == NULL || *reply_size != sizeof(int)) {
+            ALOGE("%s: EFFECT_CMD_INIT: %s, sending -EINVAL", __func__,
+                  (p_reply_data == NULL) ? "p_reply_data is NULL" :
+                  "*reply_size != sizeof(int)");
+            status = -EINVAL;
+            goto exit;
+        }
+        *(int *)p_reply_data = 0;
+        break;
+
+    case EFFECT_CMD_SET_CONFIG:
+        ALOGV("%s :: cmd called EFFECT_CMD_SET_CONFIG", __func__);
+        if (p_cmd_data == NULL || cmd_size != sizeof(effect_config_t)
+                || p_reply_data == NULL || reply_size == NULL || *reply_size != sizeof(int)) {
+            status = -EINVAL;
+            goto exit;
+        }
+        context->config = *(effect_config_t *)p_cmd_data;
+        *(int *)p_reply_data = 0;
+        break;
+
+    case EFFECT_CMD_GET_CONFIG:
+        ALOGV("%s :: cmd called EFFECT_CMD_GET_CONFIG", __func__);
+        break;
+
+    case EFFECT_CMD_RESET:
+        ALOGV("%s :: cmd called EFFECT_CMD_RESET", __func__);
+        break;
+
+    case EFFECT_CMD_SET_AUDIO_MODE:
+        ALOGV("%s :: cmd called EFFECT_CMD_SET_AUDIO_MODE", __func__);
+        break;
+
+    case EFFECT_CMD_OFFLOAD:
+        ALOGV("%s :: cmd called EFFECT_CMD_OFFLOAD", __func__);
+        if (p_reply_data == NULL || *reply_size != sizeof(int)) {
+            ALOGE("%s: EFFECT_CMD_OFFLOAD: %s, sending -EINVAL", __func__,
+                  (p_reply_data == NULL) ? "p_reply_data is NULL" :
+                  "*reply_size != sizeof(int)");
+            status = -EINVAL;
+            goto exit;
+        }
+        *(int *)p_reply_data = 0;
+        break;
+
+    case EFFECT_CMD_ENABLE:
+        ALOGV("%s :: cmd called EFFECT_CMD_ENABLE", __func__);
+        if (p_reply_data == NULL || *reply_size != sizeof(int)) {
+            ALOGE("%s: EFFECT_CMD_ENABLE: %s, sending -EINVAL", __func__,
+                   (p_reply_data == NULL) ? "p_reply_data is NULL" :
+                   "*reply_size != sizeof(int)");
+            status = -EINVAL;
+            goto exit;
+        }
+
+        if (context->state != MA_LISTENER_STATE_INITIALIZED) {
+            ALOGE("%s: EFFECT_CMD_ENABLE : state not INITIALIZED", __func__);
+            status = -ENOSYS;
+            goto exit;
+        }
+
+        context->state = MA_LISTENER_STATE_ACTIVE;
+        *(int *)p_reply_data = 0;
+
+        // After changing the state and if device is valid
+        // check and send state
+        if (valid_dev_in_context(context)) {
+            check_and_set_ma_parameter(context->stream_type);
+        }
+
+        break;
+
+    case EFFECT_CMD_DISABLE:
+        ALOGV("%s :: cmd called EFFECT_CMD_DISABLE", __func__);
+        if (p_reply_data == NULL || *reply_size != sizeof(int)) {
+            ALOGE("%s: EFFECT_CMD_DISABLE: %s, sending -EINVAL", __func__,
+                  (p_reply_data == NULL) ? "p_reply_data is NULL" :
+                  "*reply_size != sizeof(int)");
+            status = -EINVAL;
+            goto exit;
+        }
+
+        if (context->state != MA_LISTENER_STATE_ACTIVE) {
+            ALOGE("%s: EFFECT_CMD_ENABLE : state not ACTIVE", __func__);
+            status = -ENOSYS;
+            goto exit;
+        }
+
+        context->state = MA_LISTENER_STATE_INITIALIZED;
+        *(int *)p_reply_data = 0;
+
+        // After changing the state and if device is valid
+        // check and send state
+        if (valid_dev_in_context(context)) {
+            check_and_set_ma_parameter(context->stream_type);
+        }
+
+        break;
+
+    case EFFECT_CMD_GET_PARAM:
+        ALOGV("%s :: cmd called EFFECT_CMD_GET_PARAM", __func__);
+        break;
+
+    case EFFECT_CMD_SET_PARAM:
+        ALOGV("%s :: cmd called EFFECT_CMD_SET_PARAM", __func__);
+        break;
+
+    case EFFECT_CMD_SET_DEVICE:
+    {
+        uint32_t new_device;
+
+        if (p_cmd_data == NULL) {
+            ALOGE("%s: EFFECT_CMD_SET_DEVICE: cmd data NULL", __func__);
+            status = -EINVAL;
+            goto exit;
+        }
+
+        new_device = *(uint32_t *)p_cmd_data;
+        ALOGV("%s :: EFFECT_CMD_SET_DEVICE: (current/new) device (0x%x / 0x%x)",
+               __func__, context->dev_id, new_device);
+
+        context->dev_id = new_device;
+        // After changing the state and if device is valid
+        // check and send parameter
+        if (valid_dev_in_context(context)) {
+            check_and_set_ma_parameter(context->stream_type);
+        }
+    }
+    break;
+
+    case EFFECT_CMD_SET_VOLUME:
+    {
+        float left_vol = 0, right_vol = 0;
+
+        ALOGV("cmd called EFFECT_CMD_SET_VOLUME");
+        if (p_cmd_data == NULL || cmd_size != 2 * sizeof(uint32_t)) {
+            ALOGE("%s: EFFECT_CMD_SET_VOLUME: %s", __func__, (p_cmd_data == NULL) ?
+                  "p_cmd_data is NULL" : "cmd_size issue");
+            status = -EINVAL;
+            goto exit;
+        }
+
+        left_vol = (float)(*(uint32_t *)p_cmd_data) / (1 << 24);
+        right_vol = (float)(*((uint32_t *)p_cmd_data + 1)) / (1 << 24);
+        ALOGV("Current Volume (%f / %f ) new Volume (%f / %f)", context->left_vol,
+              context->right_vol, left_vol, right_vol);
+
+        context->left_vol = left_vol;
+        context->right_vol = right_vol;
+
+        // After changing the state and if device is valid
+        // check and send volume
+        if (valid_dev_in_context(context)) {
+            check_and_set_ma_parameter(context->stream_type);
+        }
+    }
+    break;
+
+    default:
+        ALOGW("%s: unknow command %d", __func__, cmd_code);
+        status = -ENOSYS;
+        break;
+    }
+
+exit:
+    pthread_mutex_unlock(&ma_listner_init_lock);
+    return status;
+}
+
+/* Effect Control Interface Implementation: get_descriptor */
+static int ma_effect_get_descriptor(effect_handle_t   self,
+                                     effect_descriptor_t *descriptor)
+{
+    ma_listener_context_t *context = (ma_listener_context_t *)self;
+    ALOGV("%s .. called ..", __func__);
+
+    if (descriptor == NULL) {
+        ALOGE("%s: descriptor is NULL", __func__);
+        return -EINVAL;
+    }
+
+    *descriptor = *context->desc;
+    return 0;
+}
+
+static void init_once()
+{
+    int ret = 0;
+    void *handle = NULL;
+    char lib_path[PATH_MAX] = {0};
+
+    if (init_state == 0) {
+        ALOGD("%s : already init ... do nothing", __func__);
+        return;
+    }
+
+    ALOGV("%s .. called ..", __func__);
+
+    send_ma_parameter = NULL;
+
+    ret = snprintf(lib_path, PATH_MAX, "%s/%s", HAL_VENDOR_PATH, HAL_LIB_NAME);
+    if (ret < 0) {
+        ALOGE("%s: snprintf failed for lib %s ret %d", __func__, HAL_LIB_NAME, ret);
+        return;
+    }
+
+    handle = dlopen(lib_path, RTLD_NOW);
+    if (handle == NULL) {
+        ALOGE("%s: DLOPEN failed for %s", __func__, HAL_LIB_NAME);
+        return;
+    } else {
+        ALOGV("%s: DLOPEN successful for %s", __func__, HAL_LIB_NAME);
+        send_ma_parameter = (bool (*)(int, float, bool))dlsym(handle, MA_SET_STATE);
+
+        if (!send_ma_parameter) {
+            ALOGE("%s: dlsym error %s for send_ma_parameter", __func__, dlerror());
+            return;
+        }
+    }
+
+    pthread_mutex_init(&ma_listner_init_lock, NULL);
+    list_init(&ma_effect_list);
+    init_state = 0;
+
+    ALOGD("%s: exit ret %d", __func__, init_state);
+}
+
+static bool lib_init()
+{
+    pthread_once(&once, init_once);
+    return init_state;
+}
+
+static int ma_prc_lib_create(const effect_uuid_t *uuid,
+                              int32_t session_id,
+                              int32_t io_id __unused,
+                              effect_handle_t *p_handle)
+{
+    int itt = 0;
+    ma_listener_context_t *context = NULL;
+
+    ALOGV("%s .. called ..", __func__);
+
+    if (lib_init() != 0) {
+        return init_state;
+    }
+
+    if (p_handle == NULL || uuid == NULL) {
+        ALOGE("%s: %s is NULL", __func__, (p_handle == NULL) ? "p_handle" : "uuid");
+        return -EINVAL;
+    }
+
+    context = (ma_listener_context_t *)calloc(1, sizeof(ma_listener_context_t));
+
+    if (context == NULL) {
+        ALOGE("%s: failed to allocate for context .. oops !!", __func__);
+        return -EINVAL;
+    }
+
+    // check if UUID is supported
+    for (itt = 0; descriptors[itt] != NULL; itt++) {
+        if (memcmp(uuid, &descriptors[itt]->uuid, sizeof(effect_uuid_t)) == 0) {
+            context->desc = descriptors[itt];
+            context->stream_type = itt;
+            PRINT_STREAM_TYPE(itt)
+            break;
+        }
+    }
+
+    if (descriptors[itt] == NULL) {
+        ALOGE("%s .. couldnt find passed uuid, something wrong", __func__);
+        free(context);
+        return -EINVAL;
+    }
+
+    ALOGV("%s CREATED_CONTEXT %p", __func__, context);
+
+    context->itfe = &effect_interface;
+    context->state = MA_LISTENER_STATE_INITIALIZED;
+    context->dev_id = AUDIO_DEVICE_NONE;
+    context->session_id = session_id;
+
+    // Add this to master list
+    pthread_mutex_lock(&ma_listner_init_lock);
+    list_add_tail(&ma_effect_list, &context->effect_list_node);
+
+    pthread_mutex_unlock(&ma_listner_init_lock);
+
+    *p_handle = (effect_handle_t)context;
+    return 0;
+}
+
+static int ma_prc_lib_release(effect_handle_t handle)
+{
+    struct listnode *node, *temp_node_next;
+    ma_listener_context_t *context = NULL;
+    ma_listener_context_t *recv_contex = (ma_listener_context_t *)handle;
+    int status = -EINVAL;
+
+    ALOGV("%s: context %p", __func__, handle);
+
+    if (recv_contex == NULL) {
+        return status;
+    }
+
+    pthread_mutex_lock(&ma_listner_init_lock);
+    // check if the handle/context provided is valid
+    list_for_each_safe(node, temp_node_next, &ma_effect_list) {
+        context = node_to_item(node, struct ma_listener_context_s, effect_list_node);
+        if (context == recv_contex) {
+            ALOGV("--- Found something to remove ---");
+            list_remove(node);
+            PRINT_STREAM_TYPE(context->stream_type);
+            free(context);
+            status = 0;
+        }
+    }
+
+    if (status != 0) {
+        ALOGE("%s: nothing to remove, ret %d", __func__, status);
+        pthread_mutex_unlock(&ma_listner_init_lock);
+        return status;
+    }
+
+    pthread_mutex_unlock(&ma_listner_init_lock);
+    return status;
+}
+
+static int ma_prc_lib_get_descriptor(const effect_uuid_t *uuid,
+                                      effect_descriptor_t *descriptor)
+{
+    int i = 0;
+
+    ALOGV("%s .. called ..", __func__);
+    if (lib_init() != 0) {
+        return init_state;
+    }
+
+    if (descriptor == NULL || uuid == NULL) {
+        ALOGE("%s: %s is NULL", __func__, (descriptor == NULL) ? "descriptor" : "uuid");
+        return -EINVAL;
+    }
+
+    for (i = 0; descriptors[i] != NULL; i++) {
+        if (memcmp(uuid, &descriptors[i]->uuid, sizeof(effect_uuid_t)) == 0) {
+            *descriptor = *descriptors[i];
+            return 0;
+        }
+    }
+
+    ALOGE("%s: couldnt found uuid passed, oops", __func__);
+    return -EINVAL;
+}
+
+
+/* effect_handle_t interface implementation for volume listener effect */
+static const struct effect_interface_s effect_interface = {
+    NULL,
+    ma_effect_command,
+    ma_effect_get_descriptor,
+    NULL,
+};
+
+__attribute__((visibility("default")))
+audio_effect_library_t AUDIO_EFFECT_LIBRARY_INFO_SYM = {
+    .tag = AUDIO_EFFECT_LIBRARY_TAG,
+    .version = EFFECT_LIBRARY_API_VERSION,
+    .name = "MAXXAUDIO Listener Effect Library",
+    .implementor = "The Android Open Source Project",
+    .create_effect = ma_prc_lib_create,
+    .release_effect = ma_prc_lib_release,
+    .get_descriptor = ma_prc_lib_get_descriptor,
+};