• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2007 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_AUDIO_HARDWARE_INTERFACE_H
18 #define ANDROID_AUDIO_HARDWARE_INTERFACE_H
19 
20 #include <stdint.h>
21 #include <sys/types.h>
22 
23 #include <utils/Errors.h>
24 #include <utils/Vector.h>
25 #include <utils/String16.h>
26 #include <utils/String8.h>
27 
28 #include <media/IAudioFlinger.h>
29 #include <hardware_legacy/AudioSystemLegacy.h>
30 
31 #include <system/audio.h>
32 #include <hardware/audio.h>
33 
34 #include <cutils/bitops.h>
35 
36 namespace android_audio_legacy {
37     using android::Vector;
38     using android::String16;
39     using android::String8;
40 
41 // ----------------------------------------------------------------------------
42 
43 /**
44  * AudioStreamOut is the abstraction interface for the audio output hardware.
45  *
46  * It provides information about various properties of the audio output hardware driver.
47  */
48 class AudioStreamOut {
49 public:
50     virtual             ~AudioStreamOut() = 0;
51 
52     /** return audio sampling rate in hz - eg. 44100 */
53     virtual uint32_t    sampleRate() const = 0;
54 
55     /** returns size of output buffer - eg. 4800 */
56     virtual size_t      bufferSize() const = 0;
57 
58     /**
59      * returns the output channel nask
60      */
61     virtual uint32_t    channels() const = 0;
62 
63     /**
64      * return audio format in 8bit or 16bit PCM format -
65      * eg. AudioSystem:PCM_16_BIT
66      */
67     virtual int         format() const = 0;
68 
69     /**
70      * return the frame size (number of bytes per sample).
71      */
frameSize()72     uint32_t    frameSize() const { return popcount(channels())*((format()==AUDIO_FORMAT_PCM_16_BIT)?sizeof(int16_t):sizeof(int8_t)); }
73 
74     /**
75      * return the audio hardware driver latency in milli seconds.
76      */
77     virtual uint32_t    latency() const = 0;
78 
79     /**
80      * Use this method in situations where audio mixing is done in the
81      * hardware. This method serves as a direct interface with hardware,
82      * allowing you to directly set the volume as apposed to via the framework.
83      * This method might produce multiple PCM outputs or hardware accelerated
84      * codecs, such as MP3 or AAC.
85      */
86     virtual status_t    setVolume(float left, float right) = 0;
87 
88     /** write audio buffer to driver. Returns number of bytes written */
89     virtual ssize_t     write(const void* buffer, size_t bytes) = 0;
90 
91     /**
92      * Put the audio hardware output into standby mode. Returns
93      * status based on include/utils/Errors.h
94      */
95     virtual status_t    standby() = 0;
96 
97     /** dump the state of the audio output device */
98     virtual status_t dump(int fd, const Vector<String16>& args) = 0;
99 
100     // set/get audio output parameters. The function accepts a list of parameters
101     // key value pairs in the form: key1=value1;key2=value2;...
102     // Some keys are reserved for standard parameters (See AudioParameter class).
103     // If the implementation does not accept a parameter change while the output is
104     // active but the parameter is acceptable otherwise, it must return INVALID_OPERATION.
105     // The audio flinger will put the output in standby and then change the parameter value.
106     virtual status_t    setParameters(const String8& keyValuePairs) = 0;
107     virtual String8     getParameters(const String8& keys) = 0;
108 
109     // return the number of audio frames written by the audio dsp to DAC since
110     // the output has exited standby
111     virtual status_t    getRenderPosition(uint32_t *dspFrames) = 0;
112 };
113 
114 /**
115  * AudioStreamIn is the abstraction interface for the audio input hardware.
116  *
117  * It defines the various properties of the audio hardware input driver.
118  */
119 class AudioStreamIn {
120 public:
121     virtual             ~AudioStreamIn() = 0;
122 
123     /** return audio sampling rate in hz - eg. 44100 */
124     virtual uint32_t    sampleRate() const = 0;
125 
126     /** return the input buffer size allowed by audio driver */
127     virtual size_t      bufferSize() const = 0;
128 
129     /** return input channel mask */
130     virtual uint32_t    channels() const = 0;
131 
132     /**
133      * return audio format in 8bit or 16bit PCM format -
134      * eg. AudioSystem:PCM_16_BIT
135      */
136     virtual int         format() const = 0;
137 
138     /**
139      * return the frame size (number of bytes per sample).
140      */
frameSize()141     uint32_t    frameSize() const { return AudioSystem::popCount(channels())*((format()==AudioSystem::PCM_16_BIT)?sizeof(int16_t):sizeof(int8_t)); }
142 
143     /** set the input gain for the audio driver. This method is for
144      *  for future use */
145     virtual status_t    setGain(float gain) = 0;
146 
147     /** read audio buffer in from audio driver */
148     virtual ssize_t     read(void* buffer, ssize_t bytes) = 0;
149 
150     /** dump the state of the audio input device */
151     virtual status_t dump(int fd, const Vector<String16>& args) = 0;
152 
153     /**
154      * Put the audio hardware input into standby mode. Returns
155      * status based on include/utils/Errors.h
156      */
157     virtual status_t    standby() = 0;
158 
159     // set/get audio input parameters. The function accepts a list of parameters
160     // key value pairs in the form: key1=value1;key2=value2;...
161     // Some keys are reserved for standard parameters (See AudioParameter class).
162     // If the implementation does not accept a parameter change while the output is
163     // active but the parameter is acceptable otherwise, it must return INVALID_OPERATION.
164     // The audio flinger will put the input in standby and then change the parameter value.
165     virtual status_t    setParameters(const String8& keyValuePairs) = 0;
166     virtual String8     getParameters(const String8& keys) = 0;
167 
168 
169     // Return the amount of input frames lost in the audio driver since the last call of this function.
170     // Audio driver is expected to reset the value to 0 and restart counting upon returning the current value by this function call.
171     // Such loss typically occurs when the user space process is blocked longer than the capacity of audio driver buffers.
172     // Unit: the number of input audio frames
173     virtual unsigned int  getInputFramesLost() const = 0;
174 
175     virtual status_t addAudioEffect(effect_handle_t effect) = 0;
176     virtual status_t removeAudioEffect(effect_handle_t effect) = 0;
177 };
178 
179 /**
180  * AudioHardwareInterface.h defines the interface to the audio hardware abstraction layer.
181  *
182  * The interface supports setting and getting parameters, selecting audio routing
183  * paths, and defining input and output streams.
184  *
185  * AudioFlinger initializes the audio hardware and immediately opens an output stream.
186  * You can set Audio routing to output to handset, speaker, Bluetooth, or a headset.
187  *
188  * The audio input stream is initialized when AudioFlinger is called to carry out
189  * a record operation.
190  */
191 class AudioHardwareInterface
192 {
193 public:
~AudioHardwareInterface()194     virtual ~AudioHardwareInterface() {}
195 
196     /**
197      * check to see if the audio hardware interface has been initialized.
198      * return status based on values defined in include/utils/Errors.h
199      */
200     virtual status_t    initCheck() = 0;
201 
202     /** set the audio volume of a voice call. Range is between 0.0 and 1.0 */
203     virtual status_t    setVoiceVolume(float volume) = 0;
204 
205     /**
206      * set the audio volume for all audio activities other than voice call.
207      * Range between 0.0 and 1.0. If any value other than NO_ERROR is returned,
208      * the software mixer will emulate this capability.
209      */
210     virtual status_t    setMasterVolume(float volume) = 0;
211 
212     /**
213      * setMode is called when the audio mode changes. NORMAL mode is for
214      * standard audio playback, RINGTONE when a ringtone is playing, and IN_CALL
215      * when a call is in progress.
216      */
217     virtual status_t    setMode(int mode) = 0;
218 
219     // mic mute
220     virtual status_t    setMicMute(bool state) = 0;
221     virtual status_t    getMicMute(bool* state) = 0;
222 
223     // set/get global audio parameters
224     virtual status_t    setParameters(const String8& keyValuePairs) = 0;
225     virtual String8     getParameters(const String8& keys) = 0;
226 
227     // Returns audio input buffer size according to parameters passed or 0 if one of the
228     // parameters is not supported
229     virtual size_t    getInputBufferSize(uint32_t sampleRate, int format, int channelCount) = 0;
230 
231     /** This method creates and opens the audio hardware output stream */
232     virtual AudioStreamOut* openOutputStream(
233                                 uint32_t devices,
234                                 int *format=0,
235                                 uint32_t *channels=0,
236                                 uint32_t *sampleRate=0,
237                                 status_t *status=0) = 0;
238     virtual    void        closeOutputStream(AudioStreamOut* out) = 0;
239     /** This method creates and opens the audio hardware input stream */
240     virtual AudioStreamIn* openInputStream(
241                                 uint32_t devices,
242                                 int *format,
243                                 uint32_t *channels,
244                                 uint32_t *sampleRate,
245                                 status_t *status,
246                                 AudioSystem::audio_in_acoustics acoustics) = 0;
247     virtual    void        closeInputStream(AudioStreamIn* in) = 0;
248 
249     /**This method dumps the state of the audio hardware */
250     virtual status_t dumpState(int fd, const Vector<String16>& args) = 0;
251 
252     static AudioHardwareInterface* create();
253 
254 protected:
255 
256     virtual status_t dump(int fd, const Vector<String16>& args) = 0;
257 };
258 
259 // ----------------------------------------------------------------------------
260 
261 extern "C" AudioHardwareInterface* createAudioHardware(void);
262 
263 }; // namespace android
264 
265 #endif // ANDROID_AUDIO_HARDWARE_INTERFACE_H
266