2 * Copyright (C) 2007 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #ifndef ANDROID_AUDIO_HARDWARE_INTERFACE_H
18 #define ANDROID_AUDIO_HARDWARE_INTERFACE_H
21 #include <sys/types.h>
23 #include <utils/Errors.h>
24 #include <utils/Vector.h>
25 #include <utils/String16.h>
26 #include <utils/String8.h>
28 #include <media/IAudioFlinger.h>
29 #include <hardware_legacy/AudioSystemLegacy.h>
31 #include <system/audio.h>
32 #include <hardware/audio.h>
34 #include <cutils/bitops.h>
36 namespace android_audio_legacy {
37 using android::Vector;
38 using android::String16;
39 using android::String8;
41 // ----------------------------------------------------------------------------
44 * AudioStreamOut is the abstraction interface for the audio output hardware.
46 * It provides information about various properties of the audio output hardware driver.
48 class AudioStreamOut {
50 virtual ~AudioStreamOut() = 0;
52 /** return audio sampling rate in hz - eg. 44100 */
53 virtual uint32_t sampleRate() const = 0;
55 /** returns size of output buffer - eg. 4800 */
56 virtual size_t bufferSize() const = 0;
59 * returns the output channel nask
61 virtual uint32_t channels() const = 0;
64 * return audio format in 8bit or 16bit PCM format -
65 * eg. AudioSystem:PCM_16_BIT
67 virtual int format() const = 0;
70 * return the frame size (number of bytes per sample).
72 uint32_t frameSize() const { return popcount(channels())*((format()==AUDIO_FORMAT_PCM_16_BIT)?sizeof(int16_t):sizeof(int8_t)); }
75 * return the audio hardware driver latency in milli seconds.
77 virtual uint32_t latency() const = 0;
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.
86 virtual status_t setVolume(float left, float right) = 0;
88 /** write audio buffer to driver. Returns number of bytes written */
89 virtual ssize_t write(const void* buffer, size_t bytes) = 0;
92 * Put the audio hardware output into standby mode. Returns
93 * status based on include/utils/Errors.h
95 virtual status_t standby() = 0;
97 /** dump the state of the audio output device */
98 virtual status_t dump(int fd, const Vector<String16>& args) = 0;
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;
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;
115 * AudioStreamIn is the abstraction interface for the audio input hardware.
117 * It defines the various properties of the audio hardware input driver.
119 class AudioStreamIn {
121 virtual ~AudioStreamIn() = 0;
123 /** return audio sampling rate in hz - eg. 44100 */
124 virtual uint32_t sampleRate() const = 0;
126 /** return the input buffer size allowed by audio driver */
127 virtual size_t bufferSize() const = 0;
129 /** return input channel mask */
130 virtual uint32_t channels() const = 0;
133 * return audio format in 8bit or 16bit PCM format -
134 * eg. AudioSystem:PCM_16_BIT
136 virtual int format() const = 0;
139 * return the frame size (number of bytes per sample).
141 uint32_t frameSize() const { return AudioSystem::popCount(channels())*((format()==AudioSystem::PCM_16_BIT)?sizeof(int16_t):sizeof(int8_t)); }
143 /** set the input gain for the audio driver. This method is for
145 virtual status_t setGain(float gain) = 0;
147 /** read audio buffer in from audio driver */
148 virtual ssize_t read(void* buffer, ssize_t bytes) = 0;
150 /** dump the state of the audio input device */
151 virtual status_t dump(int fd, const Vector<String16>& args) = 0;
154 * Put the audio hardware input into standby mode. Returns
155 * status based on include/utils/Errors.h
157 virtual status_t standby() = 0;
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;
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;
175 virtual status_t addAudioEffect(effect_handle_t effect) = 0;
176 virtual status_t removeAudioEffect(effect_handle_t effect) = 0;
180 * AudioHardwareInterface.h defines the interface to the audio hardware abstraction layer.
182 * The interface supports setting and getting parameters, selecting audio routing
183 * paths, and defining input and output streams.
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.
188 * The audio input stream is initialized when AudioFlinger is called to carry out
189 * a record operation.
191 class AudioHardwareInterface
194 virtual ~AudioHardwareInterface() {}
197 * check to see if the audio hardware interface has been initialized.
198 * return status based on values defined in include/utils/Errors.h
200 virtual status_t initCheck() = 0;
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;
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.
210 virtual status_t setMasterVolume(float volume) = 0;
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.
217 virtual status_t setMode(int mode) = 0;
220 virtual status_t setMicMute(bool state) = 0;
221 virtual status_t getMicMute(bool* state) = 0;
223 // set/get global audio parameters
224 virtual status_t setParameters(const String8& keyValuePairs) = 0;
225 virtual String8 getParameters(const String8& keys) = 0;
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;
231 /** This method creates and opens the audio hardware output stream */
232 virtual AudioStreamOut* openOutputStream(
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(
244 uint32_t *sampleRate,
246 AudioSystem::audio_in_acoustics acoustics) = 0;
247 virtual void closeInputStream(AudioStreamIn* in) = 0;
249 /**This method dumps the state of the audio hardware */
250 virtual status_t dumpState(int fd, const Vector<String16>& args) = 0;
252 static AudioHardwareInterface* create();
256 virtual status_t dump(int fd, const Vector<String16>& args) = 0;
259 // ----------------------------------------------------------------------------
261 extern "C" AudioHardwareInterface* createAudioHardware(void);
263 }; // namespace android
265 #endif // ANDROID_AUDIO_HARDWARE_INTERFACE_H