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1 /*
2  * Copyright (C) 2011 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 
18 #ifndef ANDROID_AUDIO_EFFECT_H
19 #define ANDROID_AUDIO_EFFECT_H
20 
21 #include <errno.h>
22 #include <stdint.h>
23 #include <strings.h>
24 #include <sys/cdefs.h>
25 #include <sys/types.h>
26 
27 #include <cutils/bitops.h>
28 
29 #include <system/audio.h>
30 
31 
32 __BEGIN_DECLS
33 
34 
35 /////////////////////////////////////////////////
36 //      Common Definitions
37 /////////////////////////////////////////////////
38 
39 //
40 //--- Effect descriptor structure effect_descriptor_t
41 //
42 
43 // Unique effect ID (can be generated from the following site:
44 //  http://www.itu.int/ITU-T/asn1/uuid.html)
45 // This format is used for both "type" and "uuid" fields of the effect descriptor structure.
46 // - When used for effect type and the engine is implementing and effect corresponding to a standard
47 // OpenSL ES interface, this ID must be the one defined in OpenSLES_IID.h for that interface.
48 // - When used as uuid, it should be a unique UUID for this particular implementation.
49 typedef struct effect_uuid_s {
50     uint32_t timeLow;
51     uint16_t timeMid;
52     uint16_t timeHiAndVersion;
53     uint16_t clockSeq;
54     uint8_t node[6];
55 } effect_uuid_t;
56 
57 // Maximum length of character strings in structures defines by this API.
58 #define EFFECT_STRING_LEN_MAX 64
59 
60 // NULL UUID definition (matches SL_IID_NULL_)
61 #define EFFECT_UUID_INITIALIZER { 0xec7178ec, 0xe5e1, 0x4432, 0xa3f4, \
62                                   { 0x46, 0x57, 0xe6, 0x79, 0x52, 0x10 } }
63 static const effect_uuid_t EFFECT_UUID_NULL_ = EFFECT_UUID_INITIALIZER;
64 const effect_uuid_t * const EFFECT_UUID_NULL = &EFFECT_UUID_NULL_;
65 const char * const EFFECT_UUID_NULL_STR = "ec7178ec-e5e1-4432-a3f4-4657e6795210";
66 
67 // The effect descriptor contains necessary information to facilitate the enumeration of the effect
68 // engines present in a library.
69 typedef struct effect_descriptor_s {
70     effect_uuid_t type;     // UUID of to the OpenSL ES interface implemented by this effect
71     effect_uuid_t uuid;     // UUID for this particular implementation
72     uint32_t apiVersion;    // Version of the effect control API implemented
73     uint32_t flags;         // effect engine capabilities/requirements flags (see below)
74     uint16_t cpuLoad;       // CPU load indication (see below)
75     uint16_t memoryUsage;   // Data Memory usage (see below)
76     char    name[EFFECT_STRING_LEN_MAX];   // human readable effect name
77     char    implementor[EFFECT_STRING_LEN_MAX];    // human readable effect implementor name
78 } effect_descriptor_t;
79 
80 // CPU load and memory usage indication: each effect implementation must provide an indication of
81 // its CPU and memory usage for the audio effect framework to limit the number of effects
82 // instantiated at a given time on a given platform.
83 // The CPU load is expressed in 0.1 MIPS units as estimated on an ARM9E core (ARMv5TE) with 0 WS.
84 // The memory usage is expressed in KB and includes only dynamically allocated memory
85 
86 // Definitions for flags field of effect descriptor.
87 //  +---------------------------+-----------+-----------------------------------
88 //  | description               | bits      | values
89 //  +---------------------------+-----------+-----------------------------------
90 //  | connection mode           | 0..2      | 0 insert: after track process
91 //  |                           |           | 1 auxiliary: connect to track auxiliary
92 //  |                           |           |  output and use send level
93 //  |                           |           | 2 replace: replaces track process function;
94 //  |                           |           |   must implement SRC, volume and mono to stereo.
95 //  |                           |           | 3 pre processing: applied below audio HAL on input
96 //  |                           |           | 4 post processing: applied below audio HAL on output
97 //  |                           |           | 5 - 7 reserved
98 //  +---------------------------+-----------+-----------------------------------
99 //  | insertion preference      | 3..5      | 0 none
100 //  |                           |           | 1 first of the chain
101 //  |                           |           | 2 last of the chain
102 //  |                           |           | 3 exclusive (only effect in the insert chain)
103 //  |                           |           | 4..7 reserved
104 //  +---------------------------+-----------+-----------------------------------
105 //  | Volume management         | 6..8      | 0 none
106 //  |                           |           | 1 implements volume control
107 //  |                           |           | 2 requires volume indication
108 //  |                           |           | 4 reserved
109 //  +---------------------------+-----------+-----------------------------------
110 //  | Device indication         | 9..11     | 0 none
111 //  |                           |           | 1 requires device updates
112 //  |                           |           | 2, 4 reserved
113 //  +---------------------------+-----------+-----------------------------------
114 //  | Sample input mode         | 12..13    | 1 direct: process() function or EFFECT_CMD_SET_CONFIG
115 //  |                           |           |   command must specify a buffer descriptor
116 //  |                           |           | 2 provider: process() function uses the
117 //  |                           |           |   bufferProvider indicated by the
118 //  |                           |           |   EFFECT_CMD_SET_CONFIG command to request input.
119 //  |                           |           |   buffers.
120 //  |                           |           | 3 both: both input modes are supported
121 //  +---------------------------+-----------+-----------------------------------
122 //  | Sample output mode        | 14..15    | 1 direct: process() function or EFFECT_CMD_SET_CONFIG
123 //  |                           |           |   command must specify a buffer descriptor
124 //  |                           |           | 2 provider: process() function uses the
125 //  |                           |           |   bufferProvider indicated by the
126 //  |                           |           |   EFFECT_CMD_SET_CONFIG command to request output
127 //  |                           |           |   buffers.
128 //  |                           |           | 3 both: both output modes are supported
129 //  +---------------------------+-----------+-----------------------------------
130 //  | Hardware acceleration     | 16..17    | 0 No hardware acceleration
131 //  |                           |           | 1 non tunneled hw acceleration: the process() function
132 //  |                           |           |   reads the samples, send them to HW accelerated
133 //  |                           |           |   effect processor, reads back the processed samples
134 //  |                           |           |   and returns them to the output buffer.
135 //  |                           |           | 2 tunneled hw acceleration: the process() function is
136 //  |                           |           |   transparent. The effect interface is only used to
137 //  |                           |           |   control the effect engine. This mode is relevant for
138 //  |                           |           |   global effects actually applied by the audio
139 //  |                           |           |   hardware on the output stream.
140 //  +---------------------------+-----------+-----------------------------------
141 //  | Audio Mode indication     | 18..19    | 0 none
142 //  |                           |           | 1 requires audio mode updates
143 //  |                           |           | 2..3 reserved
144 //  +---------------------------+-----------+-----------------------------------
145 //  | Audio source indication   | 20..21    | 0 none
146 //  |                           |           | 1 requires audio source updates
147 //  |                           |           | 2..3 reserved
148 //  +---------------------------+-----------+-----------------------------------
149 
150 // Insert mode
151 #define EFFECT_FLAG_TYPE_SHIFT          0
152 #define EFFECT_FLAG_TYPE_SIZE           3
153 #define EFFECT_FLAG_TYPE_MASK           (((1 << EFFECT_FLAG_TYPE_SIZE) -1) \
154                                             << EFFECT_FLAG_TYPE_SHIFT)
155 #define EFFECT_FLAG_TYPE_INSERT         (0 << EFFECT_FLAG_TYPE_SHIFT)
156 #define EFFECT_FLAG_TYPE_AUXILIARY      (1 << EFFECT_FLAG_TYPE_SHIFT)
157 #define EFFECT_FLAG_TYPE_REPLACE        (2 << EFFECT_FLAG_TYPE_SHIFT)
158 #define EFFECT_FLAG_TYPE_PRE_PROC       (3 << EFFECT_FLAG_TYPE_SHIFT)
159 #define EFFECT_FLAG_TYPE_POST_PROC      (4 << EFFECT_FLAG_TYPE_SHIFT)
160 
161 // Insert preference
162 #define EFFECT_FLAG_INSERT_SHIFT        (EFFECT_FLAG_TYPE_SHIFT + EFFECT_FLAG_TYPE_SIZE)
163 #define EFFECT_FLAG_INSERT_SIZE         3
164 #define EFFECT_FLAG_INSERT_MASK         (((1 << EFFECT_FLAG_INSERT_SIZE) -1) \
165                                             << EFFECT_FLAG_INSERT_SHIFT)
166 #define EFFECT_FLAG_INSERT_ANY          (0 << EFFECT_FLAG_INSERT_SHIFT)
167 #define EFFECT_FLAG_INSERT_FIRST        (1 << EFFECT_FLAG_INSERT_SHIFT)
168 #define EFFECT_FLAG_INSERT_LAST         (2 << EFFECT_FLAG_INSERT_SHIFT)
169 #define EFFECT_FLAG_INSERT_EXCLUSIVE    (3 << EFFECT_FLAG_INSERT_SHIFT)
170 
171 
172 // Volume control
173 #define EFFECT_FLAG_VOLUME_SHIFT        (EFFECT_FLAG_INSERT_SHIFT + EFFECT_FLAG_INSERT_SIZE)
174 #define EFFECT_FLAG_VOLUME_SIZE         3
175 #define EFFECT_FLAG_VOLUME_MASK         (((1 << EFFECT_FLAG_VOLUME_SIZE) -1) \
176                                             << EFFECT_FLAG_VOLUME_SHIFT)
177 #define EFFECT_FLAG_VOLUME_CTRL         (1 << EFFECT_FLAG_VOLUME_SHIFT)
178 #define EFFECT_FLAG_VOLUME_IND          (2 << EFFECT_FLAG_VOLUME_SHIFT)
179 #define EFFECT_FLAG_VOLUME_NONE         (0 << EFFECT_FLAG_VOLUME_SHIFT)
180 
181 // Device indication
182 #define EFFECT_FLAG_DEVICE_SHIFT        (EFFECT_FLAG_VOLUME_SHIFT + EFFECT_FLAG_VOLUME_SIZE)
183 #define EFFECT_FLAG_DEVICE_SIZE         3
184 #define EFFECT_FLAG_DEVICE_MASK         (((1 << EFFECT_FLAG_DEVICE_SIZE) -1) \
185                                             << EFFECT_FLAG_DEVICE_SHIFT)
186 #define EFFECT_FLAG_DEVICE_IND          (1 << EFFECT_FLAG_DEVICE_SHIFT)
187 #define EFFECT_FLAG_DEVICE_NONE         (0 << EFFECT_FLAG_DEVICE_SHIFT)
188 
189 // Sample input modes
190 #define EFFECT_FLAG_INPUT_SHIFT         (EFFECT_FLAG_DEVICE_SHIFT + EFFECT_FLAG_DEVICE_SIZE)
191 #define EFFECT_FLAG_INPUT_SIZE          2
192 #define EFFECT_FLAG_INPUT_MASK          (((1 << EFFECT_FLAG_INPUT_SIZE) -1) \
193                                             << EFFECT_FLAG_INPUT_SHIFT)
194 #define EFFECT_FLAG_INPUT_DIRECT        (1 << EFFECT_FLAG_INPUT_SHIFT)
195 #define EFFECT_FLAG_INPUT_PROVIDER      (2 << EFFECT_FLAG_INPUT_SHIFT)
196 #define EFFECT_FLAG_INPUT_BOTH          (3 << EFFECT_FLAG_INPUT_SHIFT)
197 
198 // Sample output modes
199 #define EFFECT_FLAG_OUTPUT_SHIFT        (EFFECT_FLAG_INPUT_SHIFT + EFFECT_FLAG_INPUT_SIZE)
200 #define EFFECT_FLAG_OUTPUT_SIZE         2
201 #define EFFECT_FLAG_OUTPUT_MASK         (((1 << EFFECT_FLAG_OUTPUT_SIZE) -1) \
202                                             << EFFECT_FLAG_OUTPUT_SHIFT)
203 #define EFFECT_FLAG_OUTPUT_DIRECT       (1 << EFFECT_FLAG_OUTPUT_SHIFT)
204 #define EFFECT_FLAG_OUTPUT_PROVIDER     (2 << EFFECT_FLAG_OUTPUT_SHIFT)
205 #define EFFECT_FLAG_OUTPUT_BOTH         (3 << EFFECT_FLAG_OUTPUT_SHIFT)
206 
207 // Hardware acceleration mode
208 #define EFFECT_FLAG_HW_ACC_SHIFT        (EFFECT_FLAG_OUTPUT_SHIFT + EFFECT_FLAG_OUTPUT_SIZE)
209 #define EFFECT_FLAG_HW_ACC_SIZE         2
210 #define EFFECT_FLAG_HW_ACC_MASK         (((1 << EFFECT_FLAG_HW_ACC_SIZE) -1) \
211                                             << EFFECT_FLAG_HW_ACC_SHIFT)
212 #define EFFECT_FLAG_HW_ACC_SIMPLE       (1 << EFFECT_FLAG_HW_ACC_SHIFT)
213 #define EFFECT_FLAG_HW_ACC_TUNNEL       (2 << EFFECT_FLAG_HW_ACC_SHIFT)
214 
215 // Audio mode indication
216 #define EFFECT_FLAG_AUDIO_MODE_SHIFT    (EFFECT_FLAG_HW_ACC_SHIFT + EFFECT_FLAG_HW_ACC_SIZE)
217 #define EFFECT_FLAG_AUDIO_MODE_SIZE     2
218 #define EFFECT_FLAG_AUDIO_MODE_MASK     (((1 << EFFECT_FLAG_AUDIO_MODE_SIZE) -1) \
219                                             << EFFECT_FLAG_AUDIO_MODE_SHIFT)
220 #define EFFECT_FLAG_AUDIO_MODE_IND      (1 << EFFECT_FLAG_AUDIO_MODE_SHIFT)
221 #define EFFECT_FLAG_AUDIO_MODE_NONE     (0 << EFFECT_FLAG_AUDIO_MODE_SHIFT)
222 
223 // Audio source indication
224 #define EFFECT_FLAG_AUDIO_SOURCE_SHIFT  (EFFECT_FLAG_AUDIO_MODE_SHIFT + EFFECT_FLAG_AUDIO_MODE_SIZE)
225 #define EFFECT_FLAG_AUDIO_SOURCE_SIZE   2
226 #define EFFECT_FLAG_AUDIO_SOURCE_MASK   (((1 << EFFECT_FLAG_AUDIO_SOURCE_SIZE) -1) \
227                                           << EFFECT_FLAG_AUDIO_SOURCE_SHIFT)
228 #define EFFECT_FLAG_AUDIO_SOURCE_IND    (1 << EFFECT_FLAG_AUDIO_SOURCE_SHIFT)
229 #define EFFECT_FLAG_AUDIO_SOURCE_NONE   (0 << EFFECT_FLAG_AUDIO_SOURCE_SHIFT)
230 
231 #define EFFECT_MAKE_API_VERSION(M, m)  (((M)<<16) | ((m) & 0xFFFF))
232 #define EFFECT_API_VERSION_MAJOR(v)    ((v)>>16)
233 #define EFFECT_API_VERSION_MINOR(v)    ((m) & 0xFFFF)
234 
235 
236 
237 /////////////////////////////////////////////////
238 //      Effect control interface
239 /////////////////////////////////////////////////
240 
241 // Effect control interface version 2.0
242 #define EFFECT_CONTROL_API_VERSION EFFECT_MAKE_API_VERSION(2,0)
243 
244 // Effect control interface structure: effect_interface_s
245 // The effect control interface is exposed by each effect engine implementation. It consists of
246 // a set of functions controlling the configuration, activation and process of the engine.
247 // The functions are grouped in a structure of type effect_interface_s.
248 //
249 // Effect control interface handle: effect_handle_t
250 // The effect_handle_t serves two purposes regarding the implementation of the effect engine:
251 // - 1 it is the address of a pointer to an effect_interface_s structure where the functions
252 // of the effect control API for a particular effect are located.
253 // - 2 it is the address of the context of a particular effect instance.
254 // A typical implementation in the effect library would define a structure as follows:
255 // struct effect_module_s {
256 //        const struct effect_interface_s *itfe;
257 //        effect_config_t config;
258 //        effect_context_t context;
259 // }
260 // The implementation of EffectCreate() function would then allocate a structure of this
261 // type and return its address as effect_handle_t
262 typedef struct effect_interface_s **effect_handle_t;
263 
264 
265 // Forward definition of type audio_buffer_t
266 typedef struct audio_buffer_s audio_buffer_t;
267 
268 
269 
270 
271 
272 
273 // Effect control interface definition
274 struct effect_interface_s {
275     ////////////////////////////////////////////////////////////////////////////////
276     //
277     //    Function:       process
278     //
279     //    Description:    Effect process function. Takes input samples as specified
280     //          (count and location) in input buffer descriptor and output processed
281     //          samples as specified in output buffer descriptor. If the buffer descriptor
282     //          is not specified the function must use either the buffer or the
283     //          buffer provider function installed by the EFFECT_CMD_SET_CONFIG command.
284     //          The effect framework will call the process() function after the EFFECT_CMD_ENABLE
285     //          command is received and until the EFFECT_CMD_DISABLE is received. When the engine
286     //          receives the EFFECT_CMD_DISABLE command it should turn off the effect gracefully
287     //          and when done indicate that it is OK to stop calling the process() function by
288     //          returning the -ENODATA status.
289     //
290     //    NOTE: the process() function implementation should be "real-time safe" that is
291     //      it should not perform blocking calls: malloc/free, sleep, read/write/open/close,
292     //      pthread_cond_wait/pthread_mutex_lock...
293     //
294     //    Input:
295     //          self:       handle to the effect interface this function
296     //              is called on.
297     //          inBuffer:   buffer descriptor indicating where to read samples to process.
298     //              If NULL, use the configuration passed by EFFECT_CMD_SET_CONFIG command.
299     //
300     //          outBuffer:   buffer descriptor indicating where to write processed samples.
301     //              If NULL, use the configuration passed by EFFECT_CMD_SET_CONFIG command.
302     //
303     //    Output:
304     //        returned value:    0 successful operation
305     //                          -ENODATA the engine has finished the disable phase and the framework
306     //                                  can stop calling process()
307     //                          -EINVAL invalid interface handle or
308     //                                  invalid input/output buffer description
309     ////////////////////////////////////////////////////////////////////////////////
310     int32_t (*process)(effect_handle_t self,
311                        audio_buffer_t *inBuffer,
312                        audio_buffer_t *outBuffer);
313     ////////////////////////////////////////////////////////////////////////////////
314     //
315     //    Function:       command
316     //
317     //    Description:    Send a command and receive a response to/from effect engine.
318     //
319     //    Input:
320     //          self:       handle to the effect interface this function
321     //              is called on.
322     //          cmdCode:    command code: the command can be a standardized command defined in
323     //              effect_command_e (see below) or a proprietary command.
324     //          cmdSize:    size of command in bytes
325     //          pCmdData:   pointer to command data
326     //          pReplyData: pointer to reply data
327     //
328     //    Input/Output:
329     //          replySize: maximum size of reply data as input
330     //                      actual size of reply data as output
331     //
332     //    Output:
333     //          returned value: 0       successful operation
334     //                          -EINVAL invalid interface handle or
335     //                                  invalid command/reply size or format according to command code
336     //              The return code should be restricted to indicate problems related to the this
337     //              API specification. Status related to the execution of a particular command should be
338     //              indicated as part of the reply field.
339     //
340     //          *pReplyData updated with command response
341     //
342     ////////////////////////////////////////////////////////////////////////////////
343     int32_t (*command)(effect_handle_t self,
344                        uint32_t cmdCode,
345                        uint32_t cmdSize,
346                        void *pCmdData,
347                        uint32_t *replySize,
348                        void *pReplyData);
349     ////////////////////////////////////////////////////////////////////////////////
350     //
351     //    Function:        get_descriptor
352     //
353     //    Description:    Returns the effect descriptor
354     //
355     //    Input:
356     //          self:       handle to the effect interface this function
357     //              is called on.
358     //
359     //    Input/Output:
360     //          pDescriptor:    address where to return the effect descriptor.
361     //
362     //    Output:
363     //        returned value:    0          successful operation.
364     //                          -EINVAL     invalid interface handle or invalid pDescriptor
365     //        *pDescriptor:     updated with the effect descriptor.
366     //
367     ////////////////////////////////////////////////////////////////////////////////
368     int32_t (*get_descriptor)(effect_handle_t self,
369                               effect_descriptor_t *pDescriptor);
370     ////////////////////////////////////////////////////////////////////////////////
371     //
372     //    Function:       process_reverse
373     //
374     //    Description:    Process reverse stream function. This function is used to pass
375     //          a reference stream to the effect engine. If the engine does not need a reference
376     //          stream, this function pointer can be set to NULL.
377     //          This function would typically implemented by an Echo Canceler.
378     //
379     //    Input:
380     //          self:       handle to the effect interface this function
381     //              is called on.
382     //          inBuffer:   buffer descriptor indicating where to read samples to process.
383     //              If NULL, use the configuration passed by EFFECT_CMD_SET_CONFIG_REVERSE command.
384     //
385     //          outBuffer:   buffer descriptor indicating where to write processed samples.
386     //              If NULL, use the configuration passed by EFFECT_CMD_SET_CONFIG_REVERSE command.
387     //              If the buffer and buffer provider in the configuration received by
388     //              EFFECT_CMD_SET_CONFIG_REVERSE are also NULL, do not return modified reverse
389     //              stream data
390     //
391     //    Output:
392     //        returned value:    0 successful operation
393     //                          -ENODATA the engine has finished the disable phase and the framework
394     //                                  can stop calling process_reverse()
395     //                          -EINVAL invalid interface handle or
396     //                                  invalid input/output buffer description
397     ////////////////////////////////////////////////////////////////////////////////
398     int32_t (*process_reverse)(effect_handle_t self,
399                                audio_buffer_t *inBuffer,
400                                audio_buffer_t *outBuffer);
401 };
402 
403 
404 //
405 //--- Standardized command codes for command() function
406 //
407 enum effect_command_e {
408    EFFECT_CMD_INIT,                 // initialize effect engine
409    EFFECT_CMD_SET_CONFIG,           // configure effect engine (see effect_config_t)
410    EFFECT_CMD_RESET,                // reset effect engine
411    EFFECT_CMD_ENABLE,               // enable effect process
412    EFFECT_CMD_DISABLE,              // disable effect process
413    EFFECT_CMD_SET_PARAM,            // set parameter immediately (see effect_param_t)
414    EFFECT_CMD_SET_PARAM_DEFERRED,   // set parameter deferred
415    EFFECT_CMD_SET_PARAM_COMMIT,     // commit previous set parameter deferred
416    EFFECT_CMD_GET_PARAM,            // get parameter
417    EFFECT_CMD_SET_DEVICE,           // set audio device (see audio.h, audio_devices_t)
418    EFFECT_CMD_SET_VOLUME,           // set volume
419    EFFECT_CMD_SET_AUDIO_MODE,       // set the audio mode (normal, ring, ...)
420    EFFECT_CMD_SET_CONFIG_REVERSE,   // configure effect engine reverse stream(see effect_config_t)
421    EFFECT_CMD_SET_INPUT_DEVICE,     // set capture device (see audio.h, audio_devices_t)
422    EFFECT_CMD_GET_CONFIG,           // read effect engine configuration
423    EFFECT_CMD_GET_CONFIG_REVERSE,   // read configure effect engine reverse stream configuration
424    EFFECT_CMD_GET_FEATURE_SUPPORTED_CONFIGS,// get all supported configurations for a feature.
425    EFFECT_CMD_GET_FEATURE_CONFIG,   // get current feature configuration
426    EFFECT_CMD_SET_FEATURE_CONFIG,   // set current feature configuration
427    EFFECT_CMD_SET_AUDIO_SOURCE,     // set the audio source (see audio.h, audio_source_t)
428    EFFECT_CMD_FIRST_PROPRIETARY = 0x10000 // first proprietary command code
429 };
430 
431 //==================================================================================================
432 // command: EFFECT_CMD_INIT
433 //--------------------------------------------------------------------------------------------------
434 // description:
435 //  Initialize effect engine: All configurations return to default
436 //--------------------------------------------------------------------------------------------------
437 // command format:
438 //  size: 0
439 //  data: N/A
440 //--------------------------------------------------------------------------------------------------
441 // reply format:
442 //  size: sizeof(int)
443 //  data: status
444 //==================================================================================================
445 // command: EFFECT_CMD_SET_CONFIG
446 //--------------------------------------------------------------------------------------------------
447 // description:
448 //  Apply new audio parameters configurations for input and output buffers
449 //--------------------------------------------------------------------------------------------------
450 // command format:
451 //  size: sizeof(effect_config_t)
452 //  data: effect_config_t
453 //--------------------------------------------------------------------------------------------------
454 // reply format:
455 //  size: sizeof(int)
456 //  data: status
457 //==================================================================================================
458 // command: EFFECT_CMD_RESET
459 //--------------------------------------------------------------------------------------------------
460 // description:
461 //  Reset the effect engine. Keep configuration but resets state and buffer content
462 //--------------------------------------------------------------------------------------------------
463 // command format:
464 //  size: 0
465 //  data: N/A
466 //--------------------------------------------------------------------------------------------------
467 // reply format:
468 //  size: 0
469 //  data: N/A
470 //==================================================================================================
471 // command: EFFECT_CMD_ENABLE
472 //--------------------------------------------------------------------------------------------------
473 // description:
474 //  Enable the process. Called by the framework before the first call to process()
475 //--------------------------------------------------------------------------------------------------
476 // command format:
477 //  size: 0
478 //  data: N/A
479 //--------------------------------------------------------------------------------------------------
480 // reply format:
481 //  size: sizeof(int)
482 //  data: status
483 //==================================================================================================
484 // command: EFFECT_CMD_DISABLE
485 //--------------------------------------------------------------------------------------------------
486 // description:
487 //  Disable the process. Called by the framework after the last call to process()
488 //--------------------------------------------------------------------------------------------------
489 // command format:
490 //  size: 0
491 //  data: N/A
492 //--------------------------------------------------------------------------------------------------
493 // reply format:
494 //  size: sizeof(int)
495 //  data: status
496 //==================================================================================================
497 // command: EFFECT_CMD_SET_PARAM
498 //--------------------------------------------------------------------------------------------------
499 // description:
500 //  Set a parameter and apply it immediately
501 //--------------------------------------------------------------------------------------------------
502 // command format:
503 //  size: sizeof(effect_param_t) + size of param and value
504 //  data: effect_param_t + param + value. See effect_param_t definition below for value offset
505 //--------------------------------------------------------------------------------------------------
506 // reply format:
507 //  size: sizeof(int)
508 //  data: status
509 //==================================================================================================
510 // command: EFFECT_CMD_SET_PARAM_DEFERRED
511 //--------------------------------------------------------------------------------------------------
512 // description:
513 //  Set a parameter but apply it only when receiving EFFECT_CMD_SET_PARAM_COMMIT command
514 //--------------------------------------------------------------------------------------------------
515 // command format:
516 //  size: sizeof(effect_param_t) + size of param and value
517 //  data: effect_param_t + param + value. See effect_param_t definition below for value offset
518 //--------------------------------------------------------------------------------------------------
519 // reply format:
520 //  size: 0
521 //  data: N/A
522 //==================================================================================================
523 // command: EFFECT_CMD_SET_PARAM_COMMIT
524 //--------------------------------------------------------------------------------------------------
525 // description:
526 //  Apply all previously received EFFECT_CMD_SET_PARAM_DEFERRED commands
527 //--------------------------------------------------------------------------------------------------
528 // command format:
529 //  size: 0
530 //  data: N/A
531 //--------------------------------------------------------------------------------------------------
532 // reply format:
533 //  size: sizeof(int)
534 //  data: status
535 //==================================================================================================
536 // command: EFFECT_CMD_GET_PARAM
537 //--------------------------------------------------------------------------------------------------
538 // description:
539 //  Get a parameter value
540 //--------------------------------------------------------------------------------------------------
541 // command format:
542 //  size: sizeof(effect_param_t) + size of param
543 //  data: effect_param_t + param
544 //--------------------------------------------------------------------------------------------------
545 // reply format:
546 //  size: sizeof(effect_param_t) + size of param and value
547 //  data: effect_param_t + param + value. See effect_param_t definition below for value offset
548 //==================================================================================================
549 // command: EFFECT_CMD_SET_DEVICE
550 //--------------------------------------------------------------------------------------------------
551 // description:
552 //  Set the rendering device the audio output path is connected to. See audio.h, audio_devices_t
553 //  for device values.
554 //  The effect implementation must set EFFECT_FLAG_DEVICE_IND flag in its descriptor to receive this
555 //  command when the device changes
556 //--------------------------------------------------------------------------------------------------
557 // command format:
558 //  size: sizeof(uint32_t)
559 //  data: uint32_t
560 //--------------------------------------------------------------------------------------------------
561 // reply format:
562 //  size: 0
563 //  data: N/A
564 //==================================================================================================
565 // command: EFFECT_CMD_SET_VOLUME
566 //--------------------------------------------------------------------------------------------------
567 // description:
568 //  Set and get volume. Used by audio framework to delegate volume control to effect engine.
569 //  The effect implementation must set EFFECT_FLAG_VOLUME_IND or EFFECT_FLAG_VOLUME_CTRL flag in
570 //  its descriptor to receive this command before every call to process() function
571 //  If EFFECT_FLAG_VOLUME_CTRL flag is set in the effect descriptor, the effect engine must return
572 //  the volume that should be applied before the effect is processed. The overall volume (the volume
573 //  actually applied by the effect engine multiplied by the returned value) should match the value
574 //  indicated in the command.
575 //--------------------------------------------------------------------------------------------------
576 // command format:
577 //  size: n * sizeof(uint32_t)
578 //  data: volume for each channel defined in effect_config_t for output buffer expressed in
579 //      8.24 fixed point format
580 //--------------------------------------------------------------------------------------------------
581 // reply format:
582 //  size: n * sizeof(uint32_t) / 0
583 //  data: - if EFFECT_FLAG_VOLUME_CTRL is set in effect descriptor:
584 //              volume for each channel defined in effect_config_t for output buffer expressed in
585 //              8.24 fixed point format
586 //        - if EFFECT_FLAG_VOLUME_CTRL is not set in effect descriptor:
587 //              N/A
588 //  It is legal to receive a null pointer as pReplyData in which case the effect framework has
589 //  delegated volume control to another effect
590 //==================================================================================================
591 // command: EFFECT_CMD_SET_AUDIO_MODE
592 //--------------------------------------------------------------------------------------------------
593 // description:
594 //  Set the audio mode. The effect implementation must set EFFECT_FLAG_AUDIO_MODE_IND flag in its
595 //  descriptor to receive this command when the audio mode changes.
596 //--------------------------------------------------------------------------------------------------
597 // command format:
598 //  size: sizeof(uint32_t)
599 //  data: audio_mode_t
600 //--------------------------------------------------------------------------------------------------
601 // reply format:
602 //  size: 0
603 //  data: N/A
604 //==================================================================================================
605 // command: EFFECT_CMD_SET_CONFIG_REVERSE
606 //--------------------------------------------------------------------------------------------------
607 // description:
608 //  Apply new audio parameters configurations for input and output buffers of reverse stream.
609 //  An example of reverse stream is the echo reference supplied to an Acoustic Echo Canceler.
610 //--------------------------------------------------------------------------------------------------
611 // command format:
612 //  size: sizeof(effect_config_t)
613 //  data: effect_config_t
614 //--------------------------------------------------------------------------------------------------
615 // reply format:
616 //  size: sizeof(int)
617 //  data: status
618 //==================================================================================================
619 // command: EFFECT_CMD_SET_INPUT_DEVICE
620 //--------------------------------------------------------------------------------------------------
621 // description:
622 //  Set the capture device the audio input path is connected to. See audio.h, audio_devices_t
623 //  for device values.
624 //  The effect implementation must set EFFECT_FLAG_DEVICE_IND flag in its descriptor to receive this
625 //  command when the device changes
626 //--------------------------------------------------------------------------------------------------
627 // command format:
628 //  size: sizeof(uint32_t)
629 //  data: uint32_t
630 //--------------------------------------------------------------------------------------------------
631 // reply format:
632 //  size: 0
633 //  data: N/A
634 //==================================================================================================
635 // command: EFFECT_CMD_GET_CONFIG
636 //--------------------------------------------------------------------------------------------------
637 // description:
638 //  Read audio parameters configurations for input and output buffers
639 //--------------------------------------------------------------------------------------------------
640 // command format:
641 //  size: 0
642 //  data: N/A
643 //--------------------------------------------------------------------------------------------------
644 // reply format:
645 //  size: sizeof(effect_config_t)
646 //  data: effect_config_t
647 //==================================================================================================
648 // command: EFFECT_CMD_GET_CONFIG_REVERSE
649 //--------------------------------------------------------------------------------------------------
650 // description:
651 //  Read audio parameters configurations for input and output buffers of reverse stream
652 //--------------------------------------------------------------------------------------------------
653 // command format:
654 //  size: 0
655 //  data: N/A
656 //--------------------------------------------------------------------------------------------------
657 // reply format:
658 //  size: sizeof(effect_config_t)
659 //  data: effect_config_t
660 //==================================================================================================
661 // command: EFFECT_CMD_GET_FEATURE_SUPPORTED_CONFIGS
662 //--------------------------------------------------------------------------------------------------
663 // description:
664 //  Queries for supported configurations for a particular feature (e.g. get the supported
665 // combinations of main and auxiliary channels for a noise suppressor).
666 // The command parameter is the feature identifier (See effect_feature_e for a list of defined
667 // features) followed by the maximum number of configuration descriptor to return.
668 // The reply is composed of:
669 //  - status (uint32_t):
670 //          - 0 if feature is supported
671 //          - -ENOSYS if the feature is not supported,
672 //          - -ENOMEM if the feature is supported but the total number of supported configurations
673 //          exceeds the maximum number indicated by the caller.
674 //  - total number of supported configurations (uint32_t)
675 //  - an array of configuration descriptors.
676 // The actual number of descriptors returned must not exceed the maximum number indicated by
677 // the caller.
678 //--------------------------------------------------------------------------------------------------
679 // command format:
680 //  size: 2 x sizeof(uint32_t)
681 //  data: effect_feature_e + maximum number of configurations to return
682 //--------------------------------------------------------------------------------------------------
683 // reply format:
684 //  size: 2 x sizeof(uint32_t) + n x sizeof (<config descriptor>)
685 //  data: status + total number of configurations supported + array of n config descriptors
686 //==================================================================================================
687 // command: EFFECT_CMD_GET_FEATURE_CONFIG
688 //--------------------------------------------------------------------------------------------------
689 // description:
690 //  Retrieves current configuration for a given feature.
691 // The reply status is:
692 //      - 0 if feature is supported
693 //      - -ENOSYS if the feature is not supported,
694 //--------------------------------------------------------------------------------------------------
695 // command format:
696 //  size: sizeof(uint32_t)
697 //  data: effect_feature_e
698 //--------------------------------------------------------------------------------------------------
699 // reply format:
700 //  size: sizeof(uint32_t) + sizeof (<config descriptor>)
701 //  data: status + config descriptor
702 //==================================================================================================
703 // command: EFFECT_CMD_SET_FEATURE_CONFIG
704 //--------------------------------------------------------------------------------------------------
705 // description:
706 //  Sets current configuration for a given feature.
707 // The reply status is:
708 //      - 0 if feature is supported
709 //      - -ENOSYS if the feature is not supported,
710 //      - -EINVAL if the configuration is invalid
711 //--------------------------------------------------------------------------------------------------
712 // command format:
713 //  size: sizeof(uint32_t) + sizeof (<config descriptor>)
714 //  data: effect_feature_e + config descriptor
715 //--------------------------------------------------------------------------------------------------
716 // reply format:
717 //  size: sizeof(uint32_t)
718 //  data: status
719 //==================================================================================================
720 // command: EFFECT_CMD_SET_AUDIO_SOURCE
721 //--------------------------------------------------------------------------------------------------
722 // description:
723 //  Set the audio source the capture path is configured for (Camcorder, voice recognition...).
724 //  See audio.h, audio_source_t for values.
725 //--------------------------------------------------------------------------------------------------
726 // command format:
727 //  size: sizeof(uint32_t)
728 //  data: uint32_t
729 //--------------------------------------------------------------------------------------------------
730 // reply format:
731 //  size: 0
732 //  data: N/A
733 //==================================================================================================
734 // command: EFFECT_CMD_FIRST_PROPRIETARY
735 //--------------------------------------------------------------------------------------------------
736 // description:
737 //  All proprietary effect commands must use command codes above this value. The size and format of
738 //  command and response fields is free in this case
739 //==================================================================================================
740 
741 
742 // Audio buffer descriptor used by process(), bufferProvider() functions and buffer_config_t
743 // structure. Multi-channel audio is always interleaved. The channel order is from LSB to MSB with
744 // regard to the channel mask definition in audio.h, audio_channel_mask_t e.g :
745 // Stereo: left, right
746 // 5 point 1: front left, front right, front center, low frequency, back left, back right
747 // The buffer size is expressed in frame count, a frame being composed of samples for all
748 // channels at a given time. Frame size for unspecified format (AUDIO_FORMAT_OTHER) is 8 bit by
749 // definition
750 struct audio_buffer_s {
751     size_t   frameCount;        // number of frames in buffer
752     union {
753         void*       raw;        // raw pointer to start of buffer
754         int32_t*    s32;        // pointer to signed 32 bit data at start of buffer
755         int16_t*    s16;        // pointer to signed 16 bit data at start of buffer
756         uint8_t*    u8;         // pointer to unsigned 8 bit data at start of buffer
757     };
758 };
759 
760 // The buffer_provider_s structure contains functions that can be used
761 // by the effect engine process() function to query and release input
762 // or output audio buffer.
763 // The getBuffer() function is called to retrieve a buffer where data
764 // should read from or written to by process() function.
765 // The releaseBuffer() function MUST be called when the buffer retrieved
766 // with getBuffer() is not needed anymore.
767 // The process function should use the buffer provider mechanism to retrieve
768 // input or output buffer if the inBuffer or outBuffer passed as argument is NULL
769 // and the buffer configuration (buffer_config_t) given by the EFFECT_CMD_SET_CONFIG
770 // command did not specify an audio buffer.
771 
772 typedef int32_t (* buffer_function_t)(void *cookie, audio_buffer_t *buffer);
773 
774 typedef struct buffer_provider_s {
775     buffer_function_t getBuffer;       // retrieve next buffer
776     buffer_function_t releaseBuffer;   // release used buffer
777     void       *cookie;                // for use by client of buffer provider functions
778 } buffer_provider_t;
779 
780 
781 // The buffer_config_s structure specifies the input or output audio format
782 // to be used by the effect engine. It is part of the effect_config_t
783 // structure that defines both input and output buffer configurations and is
784 // passed by the EFFECT_CMD_SET_CONFIG or EFFECT_CMD_SET_CONFIG_REVERSE command.
785 typedef struct buffer_config_s {
786     audio_buffer_t  buffer;     // buffer for use by process() function if not passed explicitly
787     uint32_t   samplingRate;    // sampling rate
788     uint32_t   channels;        // channel mask (see audio_channel_mask_t in audio.h)
789     buffer_provider_t bufferProvider;   // buffer provider
790     uint8_t    format;          // Audio format  (see see audio_format_t in audio.h)
791     uint8_t    accessMode;      // read/write or accumulate in buffer (effect_buffer_access_e)
792     uint16_t   mask;            // indicates which of the above fields is valid
793 } buffer_config_t;
794 
795 // Values for "accessMode" field of buffer_config_t:
796 //   overwrite, read only, accumulate (read/modify/write)
797 enum effect_buffer_access_e {
798     EFFECT_BUFFER_ACCESS_WRITE,
799     EFFECT_BUFFER_ACCESS_READ,
800     EFFECT_BUFFER_ACCESS_ACCUMULATE
801 
802 };
803 
804 // feature identifiers for EFFECT_CMD_GET_FEATURE_SUPPORTED_CONFIGS command
805 enum effect_feature_e {
806     EFFECT_FEATURE_AUX_CHANNELS, // supports auxiliary channels (e.g. dual mic noise suppressor)
807     EFFECT_FEATURE_CNT
808 };
809 
810 // EFFECT_FEATURE_AUX_CHANNELS feature configuration descriptor. Describe a combination
811 // of main and auxiliary channels supported
812 typedef struct channel_config_s {
813     audio_channel_mask_t main_channels; // channel mask for main channels
814     audio_channel_mask_t aux_channels;  // channel mask for auxiliary channels
815 } channel_config_t;
816 
817 
818 // Values for bit field "mask" in buffer_config_t. If a bit is set, the corresponding field
819 // in buffer_config_t must be taken into account when executing the EFFECT_CMD_SET_CONFIG command
820 #define EFFECT_CONFIG_BUFFER    0x0001  // buffer field must be taken into account
821 #define EFFECT_CONFIG_SMP_RATE  0x0002  // samplingRate field must be taken into account
822 #define EFFECT_CONFIG_CHANNELS  0x0004  // channels field must be taken into account
823 #define EFFECT_CONFIG_FORMAT    0x0008  // format field must be taken into account
824 #define EFFECT_CONFIG_ACC_MODE  0x0010  // accessMode field must be taken into account
825 #define EFFECT_CONFIG_PROVIDER  0x0020  // bufferProvider field must be taken into account
826 #define EFFECT_CONFIG_ALL (EFFECT_CONFIG_BUFFER | EFFECT_CONFIG_SMP_RATE | \
827                            EFFECT_CONFIG_CHANNELS | EFFECT_CONFIG_FORMAT | \
828                            EFFECT_CONFIG_ACC_MODE | EFFECT_CONFIG_PROVIDER)
829 
830 
831 // effect_config_s structure describes the format of the pCmdData argument of EFFECT_CMD_SET_CONFIG
832 // command to configure audio parameters and buffers for effect engine input and output.
833 typedef struct effect_config_s {
834     buffer_config_t   inputCfg;
835     buffer_config_t   outputCfg;
836 } effect_config_t;
837 
838 
839 // effect_param_s structure describes the format of the pCmdData argument of EFFECT_CMD_SET_PARAM
840 // command and pCmdData and pReplyData of EFFECT_CMD_GET_PARAM command.
841 // psize and vsize represent the actual size of parameter and value.
842 //
843 // NOTE: the start of value field inside the data field is always on a 32 bit boundary:
844 //
845 //  +-----------+
846 //  | status    | sizeof(int)
847 //  +-----------+
848 //  | psize     | sizeof(int)
849 //  +-----------+
850 //  | vsize     | sizeof(int)
851 //  +-----------+
852 //  |           |   |           |
853 //  ~ parameter ~   > psize     |
854 //  |           |   |           >  ((psize - 1)/sizeof(int) + 1) * sizeof(int)
855 //  +-----------+               |
856 //  | padding   |               |
857 //  +-----------+
858 //  |           |   |
859 //  ~ value     ~   > vsize
860 //  |           |   |
861 //  +-----------+
862 
863 typedef struct effect_param_s {
864     int32_t     status;     // Transaction status (unused for command, used for reply)
865     uint32_t    psize;      // Parameter size
866     uint32_t    vsize;      // Value size
867     char        data[];     // Start of Parameter + Value data
868 } effect_param_t;
869 
870 
871 
872 /////////////////////////////////////////////////
873 //      Effect library interface
874 /////////////////////////////////////////////////
875 
876 // Effect library interface version 2.0
877 #define EFFECT_LIBRARY_API_VERSION EFFECT_MAKE_API_VERSION(2,0)
878 
879 #define AUDIO_EFFECT_LIBRARY_TAG ((('A') << 24) | (('E') << 16) | (('L') << 8) | ('T'))
880 
881 // Every effect library must have a data structure named AUDIO_EFFECT_LIBRARY_INFO_SYM
882 // and the fields of this data structure must begin with audio_effect_library_t
883 
884 typedef struct audio_effect_library_s {
885     // tag must be initialized to AUDIO_EFFECT_LIBRARY_TAG
886     uint32_t tag;
887     // Version of the effect library API : 0xMMMMmmmm MMMM: Major, mmmm: minor
888     uint32_t version;
889     // Name of this library
890     const char *name;
891     // Author/owner/implementor of the library
892     const char *implementor;
893 
894     ////////////////////////////////////////////////////////////////////////////////
895     //
896     //    Function:        query_num_effects
897     //
898     //    Description:    Returns the number of different effects exposed by the
899     //          library. Each effect must have a unique effect uuid (see
900     //          effect_descriptor_t). This function together with EffectQueryEffect()
901     //          is used to enumerate all effects present in the library.
902     //
903     //    Input/Output:
904     //          pNumEffects:    address where the number of effects should be returned.
905     //
906     //    Output:
907     //        returned value:    0          successful operation.
908     //                          -ENODEV     library failed to initialize
909     //                          -EINVAL     invalid pNumEffects
910     //        *pNumEffects:     updated with number of effects in library
911     //
912     ////////////////////////////////////////////////////////////////////////////////
913     int32_t (*query_num_effects)(uint32_t *pNumEffects);
914 
915     ////////////////////////////////////////////////////////////////////////////////
916     //
917     //    Function:        query_effect
918     //
919     //    Description:    Returns the descriptor of the effect engine which index is
920     //          given as argument.
921     //          See effect_descriptor_t for details on effect descriptors.
922     //          This function together with EffectQueryNumberEffects() is used to enumerate all
923     //          effects present in the library. The enumeration sequence is:
924     //              EffectQueryNumberEffects(&num_effects);
925     //              for (i = 0; i < num_effects; i++)
926     //                  EffectQueryEffect(i,...);
927     //
928     //    Input/Output:
929     //          index:          index of the effect
930     //          pDescriptor:    address where to return the effect descriptor.
931     //
932     //    Output:
933     //        returned value:    0          successful operation.
934     //                          -ENODEV     library failed to initialize
935     //                          -EINVAL     invalid pDescriptor or index
936     //                          -ENOSYS     effect list has changed since last execution of
937     //                                      EffectQueryNumberEffects()
938     //                          -ENOENT     no more effect available
939     //        *pDescriptor:     updated with the effect descriptor.
940     //
941     ////////////////////////////////////////////////////////////////////////////////
942     int32_t (*query_effect)(uint32_t index,
943                             effect_descriptor_t *pDescriptor);
944 
945     ////////////////////////////////////////////////////////////////////////////////
946     //
947     //    Function:        create_effect
948     //
949     //    Description:    Creates an effect engine of the specified implementation uuid and
950     //          returns an effect control interface on this engine. The function will allocate the
951     //          resources for an instance of the requested effect engine and return
952     //          a handle on the effect control interface.
953     //
954     //    Input:
955     //          uuid:    pointer to the effect uuid.
956     //          sessionId:  audio session to which this effect instance will be attached. All effects
957     //              created with the same session ID are connected in series and process the same signal
958     //              stream. Knowing that two effects are part of the same effect chain can help the
959     //              library implement some kind of optimizations.
960     //          ioId:   identifies the output or input stream this effect is directed to at audio HAL.
961     //              For future use especially with tunneled HW accelerated effects
962     //
963     //    Input/Output:
964     //          pHandle:        address where to return the effect interface handle.
965     //
966     //    Output:
967     //        returned value:    0          successful operation.
968     //                          -ENODEV     library failed to initialize
969     //                          -EINVAL     invalid pEffectUuid or pHandle
970     //                          -ENOENT     no effect with this uuid found
971     //        *pHandle:         updated with the effect interface handle.
972     //
973     ////////////////////////////////////////////////////////////////////////////////
974     int32_t (*create_effect)(const effect_uuid_t *uuid,
975                              int32_t sessionId,
976                              int32_t ioId,
977                              effect_handle_t *pHandle);
978 
979     ////////////////////////////////////////////////////////////////////////////////
980     //
981     //    Function:        release_effect
982     //
983     //    Description:    Releases the effect engine whose handle is given as argument.
984     //          All resources allocated to this particular instance of the effect are
985     //          released.
986     //
987     //    Input:
988     //          handle:         handle on the effect interface to be released.
989     //
990     //    Output:
991     //        returned value:    0          successful operation.
992     //                          -ENODEV     library failed to initialize
993     //                          -EINVAL     invalid interface handle
994     //
995     ////////////////////////////////////////////////////////////////////////////////
996     int32_t (*release_effect)(effect_handle_t handle);
997 
998     ////////////////////////////////////////////////////////////////////////////////
999     //
1000     //    Function:        get_descriptor
1001     //
1002     //    Description:    Returns the descriptor of the effect engine which implementation UUID is
1003     //          given as argument.
1004     //
1005     //    Input/Output:
1006     //          uuid:           pointer to the effect uuid.
1007     //          pDescriptor:    address where to return the effect descriptor.
1008     //
1009     //    Output:
1010     //        returned value:    0          successful operation.
1011     //                          -ENODEV     library failed to initialize
1012     //                          -EINVAL     invalid pDescriptor or uuid
1013     //        *pDescriptor:     updated with the effect descriptor.
1014     //
1015     ////////////////////////////////////////////////////////////////////////////////
1016     int32_t (*get_descriptor)(const effect_uuid_t *uuid,
1017                               effect_descriptor_t *pDescriptor);
1018 } audio_effect_library_t;
1019 
1020 // Name of the hal_module_info
1021 #define AUDIO_EFFECT_LIBRARY_INFO_SYM         AELI
1022 
1023 // Name of the hal_module_info as a string
1024 #define AUDIO_EFFECT_LIBRARY_INFO_SYM_AS_STR  "AELI"
1025 
1026 __END_DECLS
1027 
1028 #endif  // ANDROID_AUDIO_EFFECT_H
1029