1 /*
2  * Copyright (C) 2009 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 #ifndef ANDROID_AUDIOEFFECT_H
18 #define ANDROID_AUDIOEFFECT_H
19 
20 #include <stdint.h>
21 #include <sys/types.h>
22 
23 #include <media/IAudioFlinger.h>
24 #include <media/IAudioPolicyService.h>
25 #include <media/IEffect.h>
26 #include <media/IEffectClient.h>
27 #include <hardware/audio_effect.h>
28 #include <media/AudioSystem.h>
29 
30 #include <utils/RefBase.h>
31 #include <utils/Errors.h>
32 #include <binder/IInterface.h>
33 
34 
35 namespace android {
36 
37 // ----------------------------------------------------------------------------
38 
39 struct effect_param_cblk_t;
40 
41 // ----------------------------------------------------------------------------
42 
43 class AudioEffect : public RefBase
44 {
45 public:
46 
47     /*
48      *  Static methods for effects enumeration.
49      */
50 
51     /*
52      * Returns the number of effects available. This method together
53      * with queryEffect() is used to enumerate all effects:
54      * The enumeration sequence is:
55      *      queryNumberEffects(&num_effects);
56      *      for (i = 0; i < num_effects; i++)
57      *          queryEffect(i,...);
58      *
59      * Parameters:
60      *      numEffects:    address where the number of effects should be returned.
61      *
62      * Returned status (from utils/Errors.h) can be:
63      *      NO_ERROR   successful operation.
64      *      PERMISSION_DENIED could not get AudioFlinger interface
65      *      NO_INIT    effect library failed to initialize
66      *      BAD_VALUE  invalid numEffects pointer
67      *
68      * Returned value
69      *   *numEffects:     updated with number of effects available
70      */
71     static status_t queryNumberEffects(uint32_t *numEffects);
72 
73     /*
74      * Returns an effect descriptor during effect
75      * enumeration.
76      *
77      * Parameters:
78      *      index:      index of the queried effect.
79      *      descriptor: address where the effect descriptor should be returned.
80      *
81      * Returned status (from utils/Errors.h) can be:
82      *      NO_ERROR        successful operation.
83      *      PERMISSION_DENIED could not get AudioFlinger interface
84      *      NO_INIT         effect library failed to initialize
85      *      BAD_VALUE       invalid descriptor pointer or index
86      *      INVALID_OPERATION  effect list has changed since last execution of queryNumberEffects()
87      *
88      * Returned value
89      *   *descriptor:     updated with effect descriptor
90      */
91     static status_t queryEffect(uint32_t index, effect_descriptor_t *descriptor);
92 
93 
94     /*
95      * Returns the descriptor for the specified effect uuid.
96      *
97      * Parameters:
98      *      uuid:       pointer to effect uuid.
99      *      descriptor: address where the effect descriptor should be returned.
100      *
101      * Returned status (from utils/Errors.h) can be:
102      *      NO_ERROR        successful operation.
103      *      PERMISSION_DENIED could not get AudioFlinger interface
104      *      NO_INIT         effect library failed to initialize
105      *      BAD_VALUE       invalid uuid or descriptor pointers
106      *      NAME_NOT_FOUND  no effect with this uuid found
107      *
108      * Returned value
109      *   *descriptor updated with effect descriptor
110      */
111     static status_t getEffectDescriptor(const effect_uuid_t *uuid,
112                                         effect_descriptor_t *descriptor) /*const*/;
113 
114 
115     /*
116      * Returns a list of descriptors corresponding to the pre processings enabled by default
117      * on an AudioRecord with the supplied audio session ID.
118      *
119      * Parameters:
120      *      audioSession:  audio session ID.
121      *      descriptors: address where the effect descriptors should be returned.
122      *      count: as input, the maximum number of descriptor than should be returned
123      *             as output, the number of descriptor returned if status is NO_ERROR or the actual
124      *             number of enabled pre processings if status is NO_MEMORY
125      *
126      * Returned status (from utils/Errors.h) can be:
127      *      NO_ERROR        successful operation.
128      *      NO_MEMORY       the number of descriptor to return is more than the maximum number
129      *                      indicated by count.
130      *      PERMISSION_DENIED could not get AudioFlinger interface
131      *      NO_INIT         effect library failed to initialize
132      *      BAD_VALUE       invalid audio session or descriptor pointers
133      *
134      * Returned value
135      *   *descriptor updated with descriptors of pre processings enabled by default
136      *   *count      number of descriptors returned if returned status is NO_ERROR.
137      *               total number of pre processing enabled by default if returned status is
138      *               NO_MEMORY. This happens if the count passed as input is less than the number
139      *               of descriptors to return.
140      *               *count is limited to kMaxPreProcessing on return.
141      */
142     static status_t queryDefaultPreProcessing(audio_session_t audioSession,
143                                               effect_descriptor_t *descriptors,
144                                               uint32_t *count);
145 
146     /*
147      * Events used by callback function (effect_callback_t).
148      */
149     enum event_type {
150         EVENT_CONTROL_STATUS_CHANGED = 0,
151         EVENT_ENABLE_STATUS_CHANGED = 1,
152         EVENT_PARAMETER_CHANGED = 2,
153         EVENT_ERROR = 3
154     };
155 
156     /* Callback function notifying client application of a change in effect engine state or
157      * configuration.
158      * An effect engine can be shared by several applications but only one has the control
159      * of the engine activity and configuration at a time.
160      * The EVENT_CONTROL_STATUS_CHANGED event is received when an application loses or
161      * retrieves the control of the effect engine. Loss of control happens
162      * if another application requests the use of the engine by creating an AudioEffect for
163      * the same effect type but with a higher priority. Control is returned when the
164      * application having the control deletes its AudioEffect object.
165      * The EVENT_ENABLE_STATUS_CHANGED event is received by all applications not having the
166      * control of the effect engine when the effect is enabled or disabled.
167      * The EVENT_PARAMETER_CHANGED event is received by all applications not having the
168      * control of the effect engine when an effect parameter is changed.
169      * The EVENT_ERROR event is received when the media server process dies.
170      *
171      * Parameters:
172      *
173      * event:   type of event notified (see enum AudioEffect::event_type).
174      * user:    Pointer to context for use by the callback receiver.
175      * info:    Pointer to optional parameter according to event type:
176      *  - EVENT_CONTROL_STATUS_CHANGED:  boolean indicating if control is granted (true)
177      *  or stolen (false).
178      *  - EVENT_ENABLE_STATUS_CHANGED: boolean indicating if effect is now enabled (true)
179      *  or disabled (false).
180      *  - EVENT_PARAMETER_CHANGED: pointer to a effect_param_t structure.
181      *  - EVENT_ERROR:  status_t indicating the error (DEAD_OBJECT when media server dies).
182      */
183 
184     typedef void (*effect_callback_t)(int32_t event, void* user, void *info);
185 
186 
187     /* Constructor.
188      * AudioEffect is the base class for creating and controlling an effect engine from
189      * the application process. Creating an AudioEffect object will create the effect engine
190      * in the AudioFlinger if no engine of the specified type exists. If one exists, this engine
191      * will be used. The application creating the AudioEffect object (or a derived class like
192      * Reverb for instance) will either receive control of the effect engine or not, depending
193      * on the priority parameter. If priority is higher than the priority used by the current
194      * effect engine owner, the control will be transfered to the new application. Otherwise
195      * control will remain to the previous application. In this case, the new application will be
196      * notified of changes in effect engine state or control ownership by the effect callback.
197      * After creating the AudioEffect, the application must call the initCheck() method and
198      * check the creation status before trying to control the effect engine (see initCheck()).
199      * If the effect is to be applied to an AudioTrack or MediaPlayer only the application
200      * must specify the audio session ID corresponding to this player.
201      */
202 
203     /* Simple Constructor.
204      *
205      * Parameters:
206      *
207      * opPackageName:      The package name used for app op checks.
208      */
209     AudioEffect(const String16& opPackageName);
210 
211 
212     /* Constructor.
213      *
214      * Parameters:
215      *
216      * type:  type of effect created: can be null if uuid is specified. This corresponds to
217      *        the OpenSL ES interface implemented by this effect.
218      * opPackageName:  The package name used for app op checks.
219      * uuid:  Uuid of effect created: can be null if type is specified. This uuid corresponds to
220      *        a particular implementation of an effect type.
221      * priority:    requested priority for effect control: the priority level corresponds to the
222      *      value of priority parameter: negative values indicate lower priorities, positive values
223      *      higher priorities, 0 being the normal priority.
224      * cbf:         optional callback function (see effect_callback_t)
225      * user:        pointer to context for use by the callback receiver.
226      * sessionID:   audio session this effect is associated to.
227      *      If equal to AUDIO_SESSION_OUTPUT_MIX, the effect will be global to
228      *      the output mix.  Otherwise, the effect will be applied to all players
229      *      (AudioTrack or MediaPLayer) within the same audio session.
230      * io:  HAL audio output or input stream to which this effect must be attached. Leave at 0 for
231      *      automatic output selection by AudioFlinger.
232      */
233 
234     AudioEffect(const effect_uuid_t *type,
235                 const String16& opPackageName,
236                 const effect_uuid_t *uuid = NULL,
237                   int32_t priority = 0,
238                   effect_callback_t cbf = NULL,
239                   void* user = NULL,
240                   audio_session_t sessionId = AUDIO_SESSION_OUTPUT_MIX,
241                   audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
242                   );
243 
244     /* Constructor.
245      *      Same as above but with type and uuid specified by character strings
246      */
247     AudioEffect(const char *typeStr,
248                     const String16& opPackageName,
249                     const char *uuidStr = NULL,
250                     int32_t priority = 0,
251                     effect_callback_t cbf = NULL,
252                     void* user = NULL,
253                     audio_session_t sessionId = AUDIO_SESSION_OUTPUT_MIX,
254                     audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
255                     );
256 
257     /* Terminates the AudioEffect and unregisters it from AudioFlinger.
258      * The effect engine is also destroyed if this AudioEffect was the last controlling
259      * the engine.
260      */
261                         ~AudioEffect();
262 
263     /* Initialize an uninitialized AudioEffect.
264     * Returned status (from utils/Errors.h) can be:
265     *  - NO_ERROR or ALREADY_EXISTS: successful initialization
266     *  - INVALID_OPERATION: AudioEffect is already initialized
267     *  - BAD_VALUE: invalid parameter
268     *  - NO_INIT: audio flinger or audio hardware not initialized
269     * */
270             status_t    set(const effect_uuid_t *type,
271                             const effect_uuid_t *uuid = NULL,
272                             int32_t priority = 0,
273                             effect_callback_t cbf = NULL,
274                             void* user = NULL,
275                             audio_session_t sessionId = AUDIO_SESSION_OUTPUT_MIX,
276                             audio_io_handle_t io = AUDIO_IO_HANDLE_NONE
277                             );
278 
279     /* Result of constructing the AudioEffect. This must be checked
280      * before using any AudioEffect API.
281      * initCheck() can return:
282      *  - NO_ERROR:    the effect engine is successfully created and the application has control.
283      *  - ALREADY_EXISTS: the effect engine is successfully created but the application does not
284      *              have control.
285      *  - NO_INIT:     the effect creation failed.
286      *
287      */
288             status_t    initCheck() const;
289 
290 
291     /* Returns the unique effect Id for the controlled effect engine. This ID is unique
292      * system wide and is used for instance in the case of auxiliary effects to attach
293      * the effect to an AudioTrack or MediaPlayer.
294      *
295      */
id()296             int32_t     id() const { return mId; }
297 
298     /* Returns a descriptor for the effect (see effect_descriptor_t in audio_effect.h).
299      */
300             effect_descriptor_t descriptor() const;
301 
302     /* Returns effect control priority of this AudioEffect object.
303      */
priority()304             int32_t     priority() const { return mPriority; }
305 
306 
307     /* Enables or disables the effect engine.
308      *
309      * Parameters:
310      *  enabled: requested enable state.
311      *
312      * Returned status (from utils/Errors.h) can be:
313      *  - NO_ERROR: successful operation
314      *  - INVALID_OPERATION: the application does not have control of the effect engine or the
315      *  effect is already in the requested state.
316      */
317     virtual status_t    setEnabled(bool enabled);
318             bool        getEnabled() const;
319 
320     /* Sets a parameter value.
321      *
322      * Parameters:
323      *      param:  pointer to effect_param_t structure containing the parameter
324      *          and its value (See audio_effect.h).
325      * Returned status (from utils/Errors.h) can be:
326      *  - NO_ERROR: successful operation.
327      *  - INVALID_OPERATION: the application does not have control of the effect engine.
328      *  - BAD_VALUE: invalid parameter identifier or value.
329      *  - DEAD_OBJECT: the effect engine has been deleted.
330      */
331      virtual status_t   setParameter(effect_param_t *param);
332 
333     /* Prepare a new parameter value that will be set by next call to
334      * setParameterCommit(). This method can be used to set multiple parameters
335      * in a synchronous manner or to avoid multiple binder calls for each
336      * parameter.
337      *
338      * Parameters:
339      *      param:  pointer to effect_param_t structure containing the parameter
340      *          and its value (See audio_effect.h).
341      *
342      * Returned status (from utils/Errors.h) can be:
343      *  - NO_ERROR: successful operation.
344      *  - INVALID_OPERATION: the application does not have control of the effect engine.
345      *  - NO_MEMORY: no more space available in shared memory used for deferred parameter
346      *  setting.
347      */
348      virtual status_t   setParameterDeferred(effect_param_t *param);
349 
350      /* Commit all parameter values previously prepared by setParameterDeferred().
351       *
352       * Parameters:
353       *     none
354       *
355       * Returned status (from utils/Errors.h) can be:
356       *  - NO_ERROR: successful operation.
357       *  - INVALID_OPERATION: No new parameter values ready for commit.
358       *  - BAD_VALUE: invalid parameter identifier or value: there is no indication
359       *     as to which of the parameters caused this error.
360       *  - DEAD_OBJECT: the effect engine has been deleted.
361       */
362      virtual status_t   setParameterCommit();
363 
364     /* Gets a parameter value.
365      *
366      * Parameters:
367      *      param:  pointer to effect_param_t structure containing the parameter
368      *          and the returned value (See audio_effect.h).
369      *
370      * Returned status (from utils/Errors.h) can be:
371      *  - NO_ERROR: successful operation.
372      *  - INVALID_OPERATION: the AudioEffect was not successfully initialized.
373      *  - BAD_VALUE: invalid parameter identifier.
374      *  - DEAD_OBJECT: the effect engine has been deleted.
375      */
376      virtual status_t   getParameter(effect_param_t *param);
377 
378      /* Sends a command and receives a response to/from effect engine.
379       *     See audio_effect.h for details on effect command() function, valid command codes
380       *     and formats.
381       */
382      virtual status_t command(uint32_t cmdCode,
383                               uint32_t cmdSize,
384                               void *cmdData,
385                               uint32_t *replySize,
386                               void *replyData);
387 
388 
389      /*
390       * Utility functions.
391       */
392 
393      /* Converts the string passed as first argument to the effect_uuid_t
394       * pointed to by second argument
395       */
396      static status_t stringToGuid(const char *str, effect_uuid_t *guid);
397      /* Converts the effect_uuid_t pointed to by first argument to the
398       * string passed as second argument
399       */
400      static status_t guidToString(const effect_uuid_t *guid, char *str, size_t maxLen);
401 
402      // kMaxPreProcessing is a reasonable value for the maximum number of preprocessing effects
403      // that can be applied simultaneously.
404      static const uint32_t kMaxPreProcessing = 10;
405 
406 protected:
407      bool                    mEnabled;           // enable state
408      audio_session_t         mSessionId;         // audio session ID
409      int32_t                 mPriority;          // priority for effect control
410      status_t                mStatus;            // effect status
411      effect_callback_t       mCbf;               // callback function for status, control and
412                                                  // parameter changes notifications
413      void*                   mUserData;          // client context for callback function
414      effect_descriptor_t     mDescriptor;        // effect descriptor
415      int32_t                 mId;                // system wide unique effect engine instance ID
416      Mutex                   mLock;              // Mutex for mEnabled access
417 
418      String16                mOpPackageName;     // The package name used for app op checks.
419 
420      // IEffectClient
421      virtual void controlStatusChanged(bool controlGranted);
422      virtual void enableStatusChanged(bool enabled);
423      virtual void commandExecuted(uint32_t cmdCode,
424              uint32_t cmdSize,
425              void *pCmdData,
426              uint32_t replySize,
427              void *pReplyData);
428 
429 private:
430 
431      // Implements the IEffectClient interface
432     class EffectClient :
433         public android::BnEffectClient, public android::IBinder::DeathRecipient
434     {
435     public:
436 
EffectClient(AudioEffect * effect)437         EffectClient(AudioEffect *effect) : mEffect(effect){}
438 
439         // IEffectClient
controlStatusChanged(bool controlGranted)440         virtual void controlStatusChanged(bool controlGranted) {
441             sp<AudioEffect> effect = mEffect.promote();
442             if (effect != 0) {
443                 effect->controlStatusChanged(controlGranted);
444             }
445         }
enableStatusChanged(bool enabled)446         virtual void enableStatusChanged(bool enabled) {
447             sp<AudioEffect> effect = mEffect.promote();
448             if (effect != 0) {
449                 effect->enableStatusChanged(enabled);
450             }
451         }
commandExecuted(uint32_t cmdCode,uint32_t cmdSize,void * pCmdData,uint32_t replySize,void * pReplyData)452         virtual void commandExecuted(uint32_t cmdCode,
453                                      uint32_t cmdSize,
454                                      void *pCmdData,
455                                      uint32_t replySize,
456                                      void *pReplyData) {
457             sp<AudioEffect> effect = mEffect.promote();
458             if (effect != 0) {
459                 effect->commandExecuted(
460                     cmdCode, cmdSize, pCmdData, replySize, pReplyData);
461             }
462         }
463 
464         // IBinder::DeathRecipient
binderDied(const wp<IBinder> & who)465         virtual void binderDied(const wp<IBinder>& who) {
466             sp<AudioEffect> effect = mEffect.promote();
467             if (effect != 0) {
468                 effect->binderDied();
469             }
470         }
471 
472     private:
473         wp<AudioEffect> mEffect;
474     };
475 
476     void binderDied();
477 
478     sp<IEffect>             mIEffect;           // IEffect binder interface
479     sp<EffectClient>        mIEffectClient;     // IEffectClient implementation
480     sp<IMemory>             mCblkMemory;        // shared memory for deferred parameter setting
481     effect_param_cblk_t*    mCblk;              // control block for deferred parameter setting
482     pid_t                   mClientPid;
483 };
484 
485 
486 }; // namespace android
487 
488 #endif // ANDROID_AUDIOEFFECT_H
489