1 /*
2  * Copyright (C) 2018 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "ma_listener"
18 /*#define LOG_NDEBUG 0*/
19 
20 #include <stdlib.h>
21 #include <dlfcn.h>
22 #include <math.h>
23 #include <pthread.h>
24 #include <unistd.h>
25 #include <cutils/list.h>
26 #include <cutils/log.h>
27 #include <hardware/audio_effect.h>
28 #include <audio-base.h>
29 
30 #define MA_FLAG ( EFFECT_FLAG_TYPE_INSERT | \
31                    EFFECT_FLAG_VOLUME_MONITOR | \
32                    EFFECT_FLAG_DEVICE_IND | \
33                    EFFECT_FLAG_OFFLOAD_SUPPORTED | \
34                    EFFECT_FLAG_NO_PROCESS)
35 
36 #define PRINT_STREAM_TYPE(i) ALOGV("descriptor found and is of stream type %s ",\
37                                                             i == AUDIO_STREAM_MUSIC ? "MUSIC": \
38                                                             i == AUDIO_STREAM_RING ? "RING": \
39                                                             i == AUDIO_STREAM_ALARM ? "ALARM": \
40                                                             i == AUDIO_STREAM_VOICE_CALL ? "Voice_call": \
41                                                             i == AUDIO_STREAM_SYSTEM ? "SYSTEM":       \
42                                                             i == AUDIO_STREAM_NOTIFICATION ? "Notification":\
43                                                             "--INVALID--"); \
44 
45 #define MA_SET_STATE "audio_hw_send_ma_parameter"
46 #define HAL_VENDOR_PATH "/vendor/lib/hw"
47 
48 enum {
49     MA_LISTENER_STATE_UNINITIALIZED,
50     MA_LISTENER_STATE_INITIALIZED,
51     MA_LISTENER_STATE_ACTIVE,
52 };
53 
54 typedef struct ma_listener_context_s ma_listener_context_t;
55 static const struct effect_interface_s effect_interface;
56 
57 struct ma_state {
58     float vol;
59     bool active;
60 };
61 
62 static const audio_stream_type_t MIN_STREAM_TYPES = AUDIO_STREAM_VOICE_CALL;
63 static const audio_stream_type_t MAX_STREAM_TYPES = AUDIO_STREAM_NOTIFICATION;
64 static struct ma_state g_cur_state[MAX_STREAM_TYPES + 1];
65 
66 struct ma_listener_context_s {
67     const struct effect_interface_s *itfe;
68     struct listnode effect_list_node;
69     effect_config_t config;
70     const effect_descriptor_t *desc;
71     uint32_t stream_type;
72     uint32_t session_id;
73     uint32_t state;
74     uint32_t dev_id;
75     float left_vol;
76     float right_vol;
77 };
78 
79 /* voice UUID: 4ece09c2-3728-11e8-a9f9-fc4dd4486b6d */
80 const effect_descriptor_t ma_listener_voice_descriptor = {
81     { 0x46f924ed, 0x25c3, 0x4272, 0x85b1, { 0x41, 0x78, 0x3f, 0x0d, 0xc6, 0x38 } },  // type
82     { 0x4ece09c2, 0x3728, 0x11e8, 0xa9f9, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
83     EFFECT_CONTROL_API_VERSION,
84     MA_FLAG,
85     0, /* TODO */
86     1,
87     "MAXXAUDIO listener for Voice",
88     "The Android Open Source Project",
89 };
90 
91 /* system UUID: 4f705ff6-3728-11e8-a0c6-fc4dd4486b6d */
92 const effect_descriptor_t ma_listener_system_descriptor = {
93     { 0x8bd0f979, 0x5266, 0x4791, 0x9213, { 0x11, 0x3a, 0xbc, 0xf7, 0xd3, 0xdc } },  // type
94     { 0x4f705ff6, 0x3728, 0x11e8, 0xa0c6, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
95     EFFECT_CONTROL_API_VERSION,
96     MA_FLAG,
97     0, /* TODO */
98     1,
99     "MAXXAUDIO listener for System",
100     "The Android Open Source Project",
101 };
102 
103 /* ring UUID: 4fd6e5c8-3728-11e8-8303-fc4dd4486b6d */
104 const effect_descriptor_t ma_listener_ring_descriptor = {
105     { 0x5380692a, 0x872e, 0x4697, 0x8e38, { 0xcd, 0xd1, 0x09, 0xf6, 0xcb, 0x87 } },  // type
106     { 0x4fd6e5c8, 0x3728, 0x11e8, 0x8303, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
107     EFFECT_CONTROL_API_VERSION,
108     MA_FLAG,
109     0, /* TODO */
110     1,
111     "MAXXAUDIO listener for Ring",
112     "The Android Open Source Project",
113 };
114 /* music UUID: 5036194e-3728-11e8-8db9-fc4dd4486b6d */
115 const effect_descriptor_t ma_listener_music_descriptor = {
116     { 0x3a3a19b2, 0x62b1, 0x4785, 0xb55e, { 0xb2, 0x8f, 0xd4, 0x1b, 0x83, 0x58 } },  // type
117     { 0x5036194e, 0x3728, 0x11e8, 0x8db9, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
118     EFFECT_CONTROL_API_VERSION,
119     MA_FLAG,
120     0, /* TODO */
121     1,
122     "MAXXAUDIO listener for Music",
123     "The Android Open Source Project",
124 };
125 /* alarm UUID: 50b9f084-3728-11e8-9225-fc4dd4486b6d */
126 const effect_descriptor_t ma_listener_alarm_descriptor = {
127     { 0x8d08d30f, 0xb4c3, 0x4600, 0x8f99, { 0xfc, 0xbb, 0x5d, 0x05, 0x8b, 0x60 } },  // type
128     { 0x50b9f084, 0x3728, 0x11e8, 0x9225, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
129     EFFECT_CONTROL_API_VERSION,
130     MA_FLAG,
131     0, /* TODO */
132     1,
133     "MAXXAUDIO listener for Alarm",
134     "The Android Open Source Project",
135 };
136 /* notification UUID: 50fe4d56-3728-11e8-ac73-fc4dd4486b6d */
137 const effect_descriptor_t ma_listener_notification_descriptor = {
138     { 0x513d09f5, 0xae7f, 0x483d, 0x922a, { 0x5c, 0x72, 0xc5, 0xe5, 0x68, 0x4c } },  // type
139     { 0x50fe4d56, 0x3728, 0x11e8, 0xac73, { 0xfc, 0x4d, 0xd4, 0x48, 0x6b, 0x6d } },  // uuid
140     EFFECT_CONTROL_API_VERSION,
141     MA_FLAG,
142     0, /* TODO */
143     1,
144     "MAXXAUDIO listener for Notification",
145     "The Android Open Source Project",
146 };
147 
148 static const effect_descriptor_t *descriptors[] = {
149     &ma_listener_voice_descriptor,
150     &ma_listener_system_descriptor,
151     &ma_listener_ring_descriptor,
152     &ma_listener_music_descriptor,
153     &ma_listener_alarm_descriptor,
154     &ma_listener_notification_descriptor,
155     NULL,
156 };
157 
158 /* function of sending state to HAL */
159 static bool (*send_ma_parameter)(int, float, bool);
160 
161 static int init_state = -1;
162 pthread_once_t once = PTHREAD_ONCE_INIT;
163 
164 struct listnode ma_effect_list;
165 pthread_mutex_t ma_listner_init_lock;
166 
167 /*
168  *  Local functions
169  */
valid_dev_in_context(struct ma_listener_context_s * context)170 static inline bool valid_dev_in_context(struct ma_listener_context_s *context)
171 {
172     /* check device */
173     if ((context->dev_id & AUDIO_DEVICE_OUT_SPEAKER) ||
174         (context->dev_id & AUDIO_DEVICE_OUT_SPEAKER_SAFE) ||
175         /* TODO: it should be dynamic if hybird split A2SP is implemented. */
176         (context->dev_id & AUDIO_DEVICE_OUT_ALL_A2DP) ||
177         (context->dev_id & AUDIO_DEVICE_OUT_ALL_USB)) {
178         return true;
179     }
180 
181     return false;
182 }
183 
check_and_set_ma_parameter(uint32_t stream_type)184 static void check_and_set_ma_parameter(uint32_t stream_type)
185 {
186     bool active = false;
187     float temp_vol = 0.0;
188     float max_vol = 0.0;
189     struct listnode *node = NULL;
190     ma_listener_context_t *context = NULL;
191 
192     ALOGV("%s .. called ..", __func__);
193     // get maximum volume for the active session with same strem type
194     list_for_each(node, &ma_effect_list) {
195         context = node_to_item(node, struct ma_listener_context_s, effect_list_node);
196         if (context->stream_type == stream_type &&
197             valid_dev_in_context(context)) {
198             if (context->state == MA_LISTENER_STATE_ACTIVE) {
199                 active = true;
200                 temp_vol = fmax(context->left_vol, context->right_vol);
201                 if (max_vol < temp_vol)
202                     max_vol = temp_vol;
203                 ALOGV("%s: check session(%d) volume(%f) for stream(%d)",
204                        __func__, context->session_id, temp_vol, stream_type);
205             }
206         }
207     }
208 
209     // check volume
210     if (max_vol < 0.0) max_vol = 0;
211     else if (max_vol > 1.0) max_vol = 1.0;
212 
213     if (send_ma_parameter != NULL &&
214         stream_type >= MIN_STREAM_TYPES &&
215         stream_type <= MAX_STREAM_TYPES &&
216         (g_cur_state[stream_type].vol != max_vol ||
217          g_cur_state[stream_type].active != active)) {
218 
219         ALOGV("%s: set stream(%d) active(%s->%s) volume(%f->%f)",
220               __func__, stream_type,
221               g_cur_state[stream_type].active ? "T" : "F", active ? "T" : "F",
222               g_cur_state[stream_type].vol, max_vol);
223 
224         // update changes to hal
225         send_ma_parameter(stream_type, max_vol, active);
226         g_cur_state[stream_type].vol = max_vol;
227         g_cur_state[stream_type].active = active;
228     }
229 
230     return;
231 }
232 
233 /*
234  * Effect Control Interface Implementation
235  */
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)236 static int ma_effect_command(effect_handle_t self,
237                               uint32_t cmd_code, uint32_t cmd_size,
238                               void *p_cmd_data, uint32_t *reply_size,
239                               void *p_reply_data)
240 {
241     ma_listener_context_t *context = (ma_listener_context_t *)self;
242     int status = 0;
243 
244     ALOGV("%s .. called ..", __func__);
245     pthread_mutex_lock(&ma_listner_init_lock);
246 
247     if (context == NULL || context->state == MA_LISTENER_STATE_UNINITIALIZED) {
248         ALOGE("%s: %s is NULL", __func__, (context == NULL) ?
249               "context" : "context->state");
250         status = -EINVAL;
251         goto exit;
252     }
253 
254     switch (cmd_code) {
255     case EFFECT_CMD_INIT:
256         ALOGV("%s :: cmd called EFFECT_CMD_INIT", __func__);
257         if (p_reply_data == NULL || *reply_size != sizeof(int)) {
258             ALOGE("%s: EFFECT_CMD_INIT: %s, sending -EINVAL", __func__,
259                   (p_reply_data == NULL) ? "p_reply_data is NULL" :
260                   "*reply_size != sizeof(int)");
261             status = -EINVAL;
262             goto exit;
263         }
264         *(int *)p_reply_data = 0;
265         break;
266 
267     case EFFECT_CMD_SET_CONFIG:
268         ALOGV("%s :: cmd called EFFECT_CMD_SET_CONFIG", __func__);
269         if (p_cmd_data == NULL || cmd_size != sizeof(effect_config_t)
270                 || p_reply_data == NULL || reply_size == NULL || *reply_size != sizeof(int)) {
271             status = -EINVAL;
272             goto exit;
273         }
274         context->config = *(effect_config_t *)p_cmd_data;
275         *(int *)p_reply_data = 0;
276         break;
277 
278     case EFFECT_CMD_GET_CONFIG:
279         ALOGV("%s :: cmd called EFFECT_CMD_GET_CONFIG", __func__);
280         break;
281 
282     case EFFECT_CMD_RESET:
283         ALOGV("%s :: cmd called EFFECT_CMD_RESET", __func__);
284         break;
285 
286     case EFFECT_CMD_SET_AUDIO_MODE:
287         ALOGV("%s :: cmd called EFFECT_CMD_SET_AUDIO_MODE", __func__);
288         break;
289 
290     case EFFECT_CMD_OFFLOAD:
291         ALOGV("%s :: cmd called EFFECT_CMD_OFFLOAD", __func__);
292         if (p_reply_data == NULL || *reply_size != sizeof(int)) {
293             ALOGE("%s: EFFECT_CMD_OFFLOAD: %s, sending -EINVAL", __func__,
294                   (p_reply_data == NULL) ? "p_reply_data is NULL" :
295                   "*reply_size != sizeof(int)");
296             status = -EINVAL;
297             goto exit;
298         }
299         *(int *)p_reply_data = 0;
300         break;
301 
302     case EFFECT_CMD_ENABLE:
303         ALOGV("%s :: cmd called EFFECT_CMD_ENABLE", __func__);
304         if (p_reply_data == NULL || *reply_size != sizeof(int)) {
305             ALOGE("%s: EFFECT_CMD_ENABLE: %s, sending -EINVAL", __func__,
306                    (p_reply_data == NULL) ? "p_reply_data is NULL" :
307                    "*reply_size != sizeof(int)");
308             status = -EINVAL;
309             goto exit;
310         }
311 
312         if (context->state != MA_LISTENER_STATE_INITIALIZED) {
313             ALOGE("%s: EFFECT_CMD_ENABLE : state not INITIALIZED", __func__);
314             status = -ENOSYS;
315             goto exit;
316         }
317 
318         context->state = MA_LISTENER_STATE_ACTIVE;
319         *(int *)p_reply_data = 0;
320 
321         // After changing the state and if device is valid
322         // check and send state
323         if (valid_dev_in_context(context)) {
324             check_and_set_ma_parameter(context->stream_type);
325         }
326 
327         break;
328 
329     case EFFECT_CMD_DISABLE:
330         ALOGV("%s :: cmd called EFFECT_CMD_DISABLE", __func__);
331         if (p_reply_data == NULL || *reply_size != sizeof(int)) {
332             ALOGE("%s: EFFECT_CMD_DISABLE: %s, sending -EINVAL", __func__,
333                   (p_reply_data == NULL) ? "p_reply_data is NULL" :
334                   "*reply_size != sizeof(int)");
335             status = -EINVAL;
336             goto exit;
337         }
338 
339         if (context->state != MA_LISTENER_STATE_ACTIVE) {
340             ALOGE("%s: EFFECT_CMD_ENABLE : state not ACTIVE", __func__);
341             status = -ENOSYS;
342             goto exit;
343         }
344 
345         context->state = MA_LISTENER_STATE_INITIALIZED;
346         *(int *)p_reply_data = 0;
347 
348         // After changing the state and if device is valid
349         // check and send state
350         if (valid_dev_in_context(context)) {
351             check_and_set_ma_parameter(context->stream_type);
352         }
353 
354         break;
355 
356     case EFFECT_CMD_GET_PARAM:
357         ALOGV("%s :: cmd called EFFECT_CMD_GET_PARAM", __func__);
358         break;
359 
360     case EFFECT_CMD_SET_PARAM:
361         ALOGV("%s :: cmd called EFFECT_CMD_SET_PARAM", __func__);
362         break;
363 
364     case EFFECT_CMD_SET_DEVICE:
365     {
366         uint32_t new_device;
367 
368         if (p_cmd_data == NULL) {
369             ALOGE("%s: EFFECT_CMD_SET_DEVICE: cmd data NULL", __func__);
370             status = -EINVAL;
371             goto exit;
372         }
373 
374         new_device = *(uint32_t *)p_cmd_data;
375         ALOGV("%s :: EFFECT_CMD_SET_DEVICE: (current/new) device (0x%x / 0x%x)",
376                __func__, context->dev_id, new_device);
377 
378         context->dev_id = new_device;
379         // After changing the state and if device is valid
380         // check and send parameter
381         if (valid_dev_in_context(context)) {
382             check_and_set_ma_parameter(context->stream_type);
383         }
384     }
385     break;
386 
387     case EFFECT_CMD_SET_VOLUME:
388     {
389         float left_vol = 0, right_vol = 0;
390 
391         ALOGV("cmd called EFFECT_CMD_SET_VOLUME");
392         if (p_cmd_data == NULL || cmd_size != 2 * sizeof(uint32_t)) {
393             ALOGE("%s: EFFECT_CMD_SET_VOLUME: %s", __func__, (p_cmd_data == NULL) ?
394                   "p_cmd_data is NULL" : "cmd_size issue");
395             status = -EINVAL;
396             goto exit;
397         }
398 
399         left_vol = (float)(*(uint32_t *)p_cmd_data) / (1 << 24);
400         right_vol = (float)(*((uint32_t *)p_cmd_data + 1)) / (1 << 24);
401         ALOGV("Current Volume (%f / %f ) new Volume (%f / %f)", context->left_vol,
402               context->right_vol, left_vol, right_vol);
403 
404         context->left_vol = left_vol;
405         context->right_vol = right_vol;
406 
407         // After changing the state and if device is valid
408         // check and send volume
409         if (valid_dev_in_context(context)) {
410             check_and_set_ma_parameter(context->stream_type);
411         }
412     }
413     break;
414 
415     default:
416         ALOGW("%s: unknow command %d", __func__, cmd_code);
417         status = -ENOSYS;
418         break;
419     }
420 
421 exit:
422     pthread_mutex_unlock(&ma_listner_init_lock);
423     return status;
424 }
425 
426 /* Effect Control Interface Implementation: get_descriptor */
ma_effect_get_descriptor(effect_handle_t self,effect_descriptor_t * descriptor)427 static int ma_effect_get_descriptor(effect_handle_t   self,
428                                      effect_descriptor_t *descriptor)
429 {
430     ma_listener_context_t *context = (ma_listener_context_t *)self;
431     ALOGV("%s .. called ..", __func__);
432 
433     if (descriptor == NULL) {
434         ALOGE("%s: descriptor is NULL", __func__);
435         return -EINVAL;
436     }
437 
438     *descriptor = *context->desc;
439     return 0;
440 }
441 
init_once()442 static void init_once()
443 {
444     int ret = 0;
445     void *handle = NULL;
446     char lib_path[PATH_MAX] = {0};
447 
448     if (init_state == 0) {
449         ALOGD("%s : already init ... do nothing", __func__);
450         return;
451     }
452 
453     ALOGV("%s .. called ..", __func__);
454 
455     send_ma_parameter = NULL;
456 
457     ret = snprintf(lib_path, PATH_MAX, "%s/%s", HAL_VENDOR_PATH, HAL_LIB_NAME);
458     if (ret < 0) {
459         ALOGE("%s: snprintf failed for lib %s ret %d", __func__, HAL_LIB_NAME, ret);
460         return;
461     }
462 
463     handle = dlopen(lib_path, RTLD_NOW);
464     if (handle == NULL) {
465         ALOGE("%s: DLOPEN failed for %s", __func__, HAL_LIB_NAME);
466         return;
467     } else {
468         ALOGV("%s: DLOPEN successful for %s", __func__, HAL_LIB_NAME);
469         send_ma_parameter = (bool (*)(int, float, bool))dlsym(handle, MA_SET_STATE);
470 
471         if (!send_ma_parameter) {
472             ALOGE("%s: dlsym error %s for send_ma_parameter", __func__, dlerror());
473             return;
474         }
475     }
476 
477     pthread_mutex_init(&ma_listner_init_lock, NULL);
478     list_init(&ma_effect_list);
479     init_state = 0;
480 
481     ALOGD("%s: exit ret %d", __func__, init_state);
482 }
483 
lib_init()484 static bool lib_init()
485 {
486     pthread_once(&once, init_once);
487     return init_state;
488 }
489 
ma_prc_lib_create(const effect_uuid_t * uuid,int32_t session_id,int32_t io_id __unused,effect_handle_t * p_handle)490 static int ma_prc_lib_create(const effect_uuid_t *uuid,
491                               int32_t session_id,
492                               int32_t io_id __unused,
493                               effect_handle_t *p_handle)
494 {
495     int itt = 0;
496     ma_listener_context_t *context = NULL;
497 
498     ALOGV("%s .. called ..", __func__);
499 
500     if (lib_init() != 0) {
501         return init_state;
502     }
503 
504     if (p_handle == NULL || uuid == NULL) {
505         ALOGE("%s: %s is NULL", __func__, (p_handle == NULL) ? "p_handle" : "uuid");
506         return -EINVAL;
507     }
508 
509     context = (ma_listener_context_t *)calloc(1, sizeof(ma_listener_context_t));
510 
511     if (context == NULL) {
512         ALOGE("%s: failed to allocate for context .. oops !!", __func__);
513         return -EINVAL;
514     }
515 
516     // check if UUID is supported
517     for (itt = 0; descriptors[itt] != NULL; itt++) {
518         if (memcmp(uuid, &descriptors[itt]->uuid, sizeof(effect_uuid_t)) == 0) {
519             context->desc = descriptors[itt];
520             context->stream_type = itt;
521             PRINT_STREAM_TYPE(itt)
522             break;
523         }
524     }
525 
526     if (descriptors[itt] == NULL) {
527         ALOGE("%s .. couldnt find passed uuid, something wrong", __func__);
528         free(context);
529         return -EINVAL;
530     }
531 
532     ALOGV("%s CREATED_CONTEXT %p", __func__, context);
533 
534     context->itfe = &effect_interface;
535     context->state = MA_LISTENER_STATE_INITIALIZED;
536     context->dev_id = AUDIO_DEVICE_NONE;
537     context->session_id = session_id;
538 
539     // Add this to master list
540     pthread_mutex_lock(&ma_listner_init_lock);
541     list_add_tail(&ma_effect_list, &context->effect_list_node);
542 
543     pthread_mutex_unlock(&ma_listner_init_lock);
544 
545     *p_handle = (effect_handle_t)context;
546     return 0;
547 }
548 
ma_prc_lib_release(effect_handle_t handle)549 static int ma_prc_lib_release(effect_handle_t handle)
550 {
551     struct listnode *node, *temp_node_next;
552     ma_listener_context_t *context = NULL;
553     ma_listener_context_t *recv_contex = (ma_listener_context_t *)handle;
554     int status = -EINVAL;
555 
556     ALOGV("%s: context %p", __func__, handle);
557 
558     if (recv_contex == NULL) {
559         return status;
560     }
561 
562     pthread_mutex_lock(&ma_listner_init_lock);
563     // check if the handle/context provided is valid
564     list_for_each_safe(node, temp_node_next, &ma_effect_list) {
565         context = node_to_item(node, struct ma_listener_context_s, effect_list_node);
566         if (context == recv_contex) {
567             ALOGV("--- Found something to remove ---");
568             list_remove(node);
569             PRINT_STREAM_TYPE(context->stream_type);
570             free(context);
571             status = 0;
572         }
573     }
574 
575     if (status != 0) {
576         ALOGE("%s: nothing to remove, ret %d", __func__, status);
577         pthread_mutex_unlock(&ma_listner_init_lock);
578         return status;
579     }
580 
581     pthread_mutex_unlock(&ma_listner_init_lock);
582     return status;
583 }
584 
ma_prc_lib_get_descriptor(const effect_uuid_t * uuid,effect_descriptor_t * descriptor)585 static int ma_prc_lib_get_descriptor(const effect_uuid_t *uuid,
586                                       effect_descriptor_t *descriptor)
587 {
588     int i = 0;
589 
590     ALOGV("%s .. called ..", __func__);
591     if (lib_init() != 0) {
592         return init_state;
593     }
594 
595     if (descriptor == NULL || uuid == NULL) {
596         ALOGE("%s: %s is NULL", __func__, (descriptor == NULL) ? "descriptor" : "uuid");
597         return -EINVAL;
598     }
599 
600     for (i = 0; descriptors[i] != NULL; i++) {
601         if (memcmp(uuid, &descriptors[i]->uuid, sizeof(effect_uuid_t)) == 0) {
602             *descriptor = *descriptors[i];
603             return 0;
604         }
605     }
606 
607     ALOGE("%s: couldnt found uuid passed, oops", __func__);
608     return -EINVAL;
609 }
610 
611 
612 /* effect_handle_t interface implementation for volume listener effect */
613 static const struct effect_interface_s effect_interface = {
614     NULL,
615     ma_effect_command,
616     ma_effect_get_descriptor,
617     NULL,
618 };
619 
620 __attribute__((visibility("default")))
621 audio_effect_library_t AUDIO_EFFECT_LIBRARY_INFO_SYM = {
622     .tag = AUDIO_EFFECT_LIBRARY_TAG,
623     .version = EFFECT_LIBRARY_API_VERSION,
624     .name = "MAXXAUDIO Listener Effect Library",
625     .implementor = "The Android Open Source Project",
626     .create_effect = ma_prc_lib_create,
627     .release_effect = ma_prc_lib_release,
628     .get_descriptor = ma_prc_lib_get_descriptor,
629 };
630