Android10 车载音频架构之动态路由的配置
启用 AAOS 路由
xref: /packages/services/Car/service/res/values/config.xml
true
如果设为 false，路由和大部分 CarAudioService 将被停用，并且 AAOS 会回退到 AudioService 的默认行为。
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioService.java
202 public CarAudioService(Context context) {
203 mContext = context;
204 mTelephonyManager = (TelephonyManager) mContext.getSystemService(Context.TELEPHONY_SERVICE);
205 mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
206 mUseDynamicRouting = mContext.getResources().getBoolean(R.bool.audioUseDynamicRouting);
207 mPersistMasterMuteState = mContext.getResources().getBoolean(
208 R.bool.audioPersistMasterMuteState);
209 mUidToZoneMap = new HashMap<>();
210 }
211
212 /**
213 * Dynamic routing and volume groups are set only if
214 * {@link #mUseDynamicRouting} is {@code true}. Otherwise, this service runs in legacy mode.
215 */
216 @Override
217 public void init() {
218 synchronized (mImplLock) {
219 if (mUseDynamicRouting) {
220 // Enumerate all output bus device ports
221 AudioDeviceInfo[] deviceInfos = mAudioManager.getDevices(
222 AudioManager.GET_DEVICES_OUTPUTS);
223 if (deviceInfos.length == 0) {
224 Log.e(CarLog.TAG_AUDIO, "No output device available, ignore");
225 return;
226 }
227 SparseArray busToCarAudioDeviceInfo = new SparseArray<>();
228 for (AudioDeviceInfo info : deviceInfos) {
229 Log.v(CarLog.TAG_AUDIO, String.format("output id=%d address=%s type=%s",
230 info.getId(), info.getAddress(), info.getType()));
231 if (info.getType() == AudioDeviceInfo.TYPE_BUS) {
232 final CarAudioDeviceInfo carInfo = new CarAudioDeviceInfo(info);
233 // See also the audio_policy_configuration.xml,
234 // the bus number should be no less than zero.
235 if (carInfo.getBusNumber() >= 0) {
236 busToCarAudioDeviceInfo.put(carInfo.getBusNumber(), carInfo);
237 Log.i(CarLog.TAG_AUDIO, "Valid bus found " + carInfo);
238 }
239 }
240 }
241 setupDynamicRouting(busToCarAudioDeviceInfo);
242 } else {
243 Log.i(CarLog.TAG_AUDIO, "Audio dynamic routing not enabled, run in legacy mode");
244 setupLegacyVolumeChangedListener();
245 }
246
247 // Restore master mute state if applicable
248 if (mPersistMasterMuteState) {
249 boolean storedMasterMute = Settings.Global.getInt(mContext.getContentResolver(),
250 VOLUME_SETTINGS_KEY_MASTER_MUTE, 0) != 0;
251 setMasterMute(storedMasterMute, 0);
252 }
253 }
254 } 解析config.xml文件，如果audioUseDynamicRouting是true，则mUseDynamicRouting也是true，执行init函数的时候将走动态路由策略。
a.通过AudioManager获取到所以输出总线设备
b.过滤出type是AudioDeviceInfo.TYPE_BUS的输出设备,然后重新封装到CarAudioDeviceInfo中
c.设置动态路由
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioDeviceInfo.java
41 /**
42 * Parse device address. Expected format is BUS%d_%s, address, usage hint
43 * @return valid address (from 0 to positive) or -1 for invalid address.
44 */
45 static int parseDeviceAddress(String address) {
46 String[] words = address.split("_");
47 int addressParsed = -1;
48 if (words[0].toLowerCase().startsWith("bus")) {
49 try {
50 addressParsed = Integer.parseInt(words[0].substring(3));
51 } catch (NumberFormatException e) {
52 //ignore
53 }
54 }
55 if (addressParsed < 0) {
56 return -1;
57 }
58 return addressParsed;
59 }
.....................................
77 CarAudioDeviceInfo(AudioDeviceInfo audioDeviceInfo) {
78 mAudioDeviceInfo = audioDeviceInfo;
79 mBusNumber = parseDeviceAddress(audioDeviceInfo.getAddress());
80 mSampleRate = getMaxSampleRate(audioDeviceInfo);
81 mEncodingFormat = getEncodingFormat(audioDeviceInfo);
82 mChannelCount = getMaxChannels(audioDeviceInfo);
83 final AudioGain audioGain = Preconditions.checkNotNull(
84 getAudioGain(), "No audio gain on device port " + audioDeviceInfo);
85 mDefaultGain = audioGain.defaultValue();
86 mMaxGain = audioGain.maxValue();
87 mMinGain = audioGain.minValue();
88
89 mCurrentGain = -1; // Not initialized till explicitly set
90 }解析device address获取到busNumber，找到bus和第一个"_"中间的字符截取出来转成int。
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioService.java
99 private static final String[] AUDIO_CONFIGURATION_PATHS = new String[] {
100 "/vendor/etc/car_audio_configuration.xml",
101 "/system/etc/car_audio_configuration.xml"
102 };
...........................
439 private void setupDynamicRouting(SparseArray busToCarAudioDeviceInfo) {
440 final AudioPolicy.Builder builder = new AudioPolicy.Builder(mContext);
441 builder.setLooper(Looper.getMainLooper());
442
443 mCarAudioConfigurationPath = getAudioConfigurationPath();
444 if (mCarAudioConfigurationPath != null) {
445 try (InputStream inputStream = new FileInputStream(mCarAudioConfigurationPath)) {
446 CarAudioZonesHelper zonesHelper = new CarAudioZonesHelper(mContext, inputStream,
447 busToCarAudioDeviceInfo);
448 mCarAudioZones = zonesHelper.loadAudioZones();
449 } catch (IOException | XmlPullParserException e) {
450 throw new RuntimeException("Failed to parse audio zone configuration", e);
451 }
452 } else {
453 // In legacy mode, context -> bus mapping is done by querying IAudioControl HAL.
454 final IAudioControl audioControl = getAudioControl();
455 if (audioControl == null) {
456 throw new RuntimeException(
457 "Dynamic routing requested but audioControl HAL not available");
458 }
459 CarAudioZonesHelperLegacy legacyHelper = new CarAudioZonesHelperLegacy(mContext,
460 R.xml.car_volume_groups, busToCarAudioDeviceInfo, audioControl);
461 mCarAudioZones = legacyHelper.loadAudioZones();
462 }
463 for (CarAudioZone zone : mCarAudioZones) {
464 if (!zone.validateVolumeGroups()) {
465 throw new RuntimeException("Invalid volume groups configuration");
466 }
467 // Ensure HAL gets our initial value
468 zone.synchronizeCurrentGainIndex();
469 Log.v(CarLog.TAG_AUDIO, "Processed audio zone: " + zone);
470 }
471
472 // Setup dynamic routing rules by usage
473 final CarAudioDynamicRouting dynamicRouting = new CarAudioDynamicRouting(mCarAudioZones);
474 dynamicRouting.setupAudioDynamicRouting(builder);
475
476 // Attach the {@link AudioPolicyVolumeCallback}
477 builder.setAudioPolicyVolumeCallback(mAudioPolicyVolumeCallback);
478
479 if (sUseCarAudioFocus) {
480 // Configure our AudioPolicy to handle focus events.
481 // This gives us the ability to decide which audio focus requests to accept and bypasses
482 // the framework ducking logic.
483 mFocusHandler = new CarZonesAudioFocus(mAudioManager,
484 mContext.getPackageManager(),
485 mCarAudioZones);
486 builder.setAudioPolicyFocusListener(mFocusHandler);
487 builder.setIsAudioFocusPolicy(true);
488 }
489
490 mAudioPolicy = builder.build();
491 if (sUseCarAudioFocus) {
492 // Connect the AudioPolicy and the focus listener
493 mFocusHandler.setOwningPolicy(this, mAudioPolicy);
494 }
495
496 int r = mAudioManager.registerAudioPolicy(mAudioPolicy);
497 if (r != AudioManager.SUCCESS) {
498 throw new RuntimeException("registerAudioPolicy failed " + r);
499 }
500 } 通过getAudioConfigurationPath获取配置文件路径，然后解析配置文件。
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioZonesHelper.java
64 private static final Map CONTEXT_NAME_MAP;
65
66 static {
67 CONTEXT_NAME_MAP = new HashMap<>();
68 CONTEXT_NAME_MAP.put("music", ContextNumber.MUSIC);
69 CONTEXT_NAME_MAP.put("navigation", ContextNumber.NAVIGATION);
70 CONTEXT_NAME_MAP.put("voice_command", ContextNumber.VOICE_COMMAND);
71 CONTEXT_NAME_MAP.put("call_ring", ContextNumber.CALL_RING);
72 CONTEXT_NAME_MAP.put("call", ContextNumber.CALL);
73 CONTEXT_NAME_MAP.put("alarm", ContextNumber.ALARM);
74 CONTEXT_NAME_MAP.put("notification", ContextNumber.NOTIFICATION);
75 CONTEXT_NAME_MAP.put("system_sound", ContextNumber.SYSTEM_SOUND);
76 }
......................................
232 private void parseVolumeGroupContexts(
233 XmlPullParser parser, CarVolumeGroup group, int busNumber)
234 throws XmlPullParserException, IOException {
235 while (parser.next() != XmlPullParser.END_TAG) {
236 if (parser.getEventType() != XmlPullParser.START_TAG) continue;
237 if (TAG_CONTEXT.equals(parser.getName())) {
238 group.bind(
239 parseContextNumber(parser.getAttributeValue(NAMESPACE, ATTR_CONTEXT_NAME)),
240 busNumber, mBusToCarAudioDeviceInfo.get(busNumber));
241 }
242 // Always skip to upper level since we're at the lowest.
243 skip(parser);
244 }
245 }
......................................
264 private int parseContextNumber(String context) {
265 return CONTEXT_NAME_MAP.getOrDefault(context.toLowerCase(), ContextNumber.INVALID);
266 } xref: /packages/services/Car/service/src/com/android/car/audio/CarVolumeGroup.java
134 /**
135 * Binds the context number to physical bus number and audio device port information.
136 * Because this may change the groups min/max values, thus invalidating an index computed from
137 * a gain before this call, all calls to this function must happen at startup before any
138 * set/getGainIndex calls.
139 *
140 * @param contextNumber Context number as defined in audio control HAL
141 * @param busNumber Physical bus number for the audio device port
142 * @param info {@link CarAudioDeviceInfo} instance relates to the physical bus
143 */
144 void bind(int contextNumber, int busNumber, CarAudioDeviceInfo info) {
145 if (mBusToCarAudioDeviceInfo.size() == 0) {
146 mStepSize = info.getAudioGain().stepValue();
147 } else {
148 Preconditions.checkArgument(
149 info.getAudioGain().stepValue() == mStepSize,
150 "Gain controls within one group must have same step value");
151 }
152
153 mContextToBus.put(contextNumber, busNumber);
154 mBusToCarAudioDeviceInfo.put(busNumber, info);
155
156 if (info.getDefaultGain() > mDefaultGain) {
157 // We're arbitrarily selecting the highest bus default gain as the group's default.
158 mDefaultGain = info.getDefaultGain();
159 }
160 if (info.getMaxGain() > mMaxGain) {
161 mMaxGain = info.getMaxGain();
162 }
163 if (info.getMinGain() < mMinGain) {
164 mMinGain = info.getMinGain();
165 }
166 if (mStoredGainIndex < getMinGainIndex() || mStoredGainIndex > getMaxGainIndex()) {
167 // We expected to load a value from last boot, but if we didn't (perhaps this is the
168 // first boot ever?), then use the highest "default" we've seen to initialize
169 // ourselves.
170 mCurrentGainIndex = getIndexForGain(mDefaultGain);
171 } else {
172 // Just use the gain index we stored last time the gain was set (presumably during our
173 // last boot cycle).
174 mCurrentGainIndex = mStoredGainIndex;
175 }
176 }mContextToBus.put(contextNumber, busNumber);将contextNumber与busNumber 相对应。 mBusToCarAudioDeviceInfo.put(busNumber, info);将busNumber与info相对应。这样每个contextNumber都对应着具体的输出设备。接下来看contextNumber是如何产生的。
car_audio_configuration.xml
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audio_policy_configuration.xml
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54 - bus0_media_out
55 - bus1_navigation_out
56 - bus2_voice_command_out
57 - bus3_call_ring_out
58 - bus4_call_out
59 - bus5_alarm_out
60 - bus6_notification_out
61 - bus7_system_sound_out
62 - bus100_rear_seat
63 - Built-In Mic
64 - Built-In Back Mic
65 - Echo-Reference Mic
66 - FM Tuner
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68 bus0_media_out
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273 通过CONTEXT_NAME_MAP关系，根据context可以找到contextNumber。
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioService.java
472 // Setup dynamic routing rules by usage
473 final CarAudioDynamicRouting dynamicRouting = new CarAudioDynamicRouting(mCarAudioZones);
474 dynamicRouting.setupAudioDynamicRouting(builder);通过usage设置动态路由策略
xref: /packages/services/Car/service/src/com/android/car/audio/CarAudioDynamicRouting.java
50 static final SparseIntArray USAGE_TO_CONTEXT = new SparseIntArray();
...............................................
67 static {
68 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_UNKNOWN, ContextNumber.MUSIC);
69 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_MEDIA, ContextNumber.MUSIC);
70 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_VOICE_COMMUNICATION, ContextNumber.CALL);
71 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_VOICE_COMMUNICATION_SIGNALLING,
72 ContextNumber.CALL);
73 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_ALARM, ContextNumber.ALARM);
74 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION, ContextNumber.NOTIFICATION);
75 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION_RINGTONE, ContextNumber.CALL_RING);
76 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION_COMMUNICATION_REQUEST,
77 ContextNumber.NOTIFICATION);
78 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION_COMMUNICATION_INSTANT,
79 ContextNumber.NOTIFICATION);
80 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION_COMMUNICATION_DELAYED,
81 ContextNumber.NOTIFICATION);
82 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_NOTIFICATION_EVENT, ContextNumber.NOTIFICATION);
83 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_ASSISTANCE_ACCESSIBILITY,
84 ContextNumber.VOICE_COMMAND);
85 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_ASSISTANCE_NAVIGATION_GUIDANCE,
86 ContextNumber.NAVIGATION);
87 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_ASSISTANCE_SONIFICATION,
88 ContextNumber.SYSTEM_SOUND);
89 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_GAME, ContextNumber.MUSIC);
90 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_VIRTUAL_SOURCE, ContextNumber.INVALID);
91 USAGE_TO_CONTEXT.put(AudioAttributes.USAGE_ASSISTANT, ContextNumber.VOICE_COMMAND);
92 }
.......................................
100 void setupAudioDynamicRouting(AudioPolicy.Builder builder) {
101 for (CarAudioZone zone : mCarAudioZones) {
102 for (CarVolumeGroup group : zone.getVolumeGroups()) {
103 setupAudioDynamicRoutingForGroup(group, builder);
104 }
105 }
106 }
107
108 /**
109 * Enumerates all physical buses in a given volume group and attach the mixing rules.
110 * @param group {@link CarVolumeGroup} instance to enumerate the buses with
111 * @param builder {@link AudioPolicy.Builder} to attach the mixing rules
112 */
113 private void setupAudioDynamicRoutingForGroup(CarVolumeGroup group,
114 AudioPolicy.Builder builder) {
115 // Note that one can not register audio mix for same bus more than once.
116 for (int busNumber : group.getBusNumbers()) {
117 boolean hasContext = false;
118 CarAudioDeviceInfo info = group.getCarAudioDeviceInfoForBus(busNumber);
119 AudioFormat mixFormat = new AudioFormat.Builder()
120 .setSampleRate(info.getSampleRate())
121 .setEncoding(info.getEncodingFormat())
122 .setChannelMask(info.getChannelCount())
123 .build();
124 AudioMixingRule.Builder mixingRuleBuilder = new AudioMixingRule.Builder();
125 for (int contextNumber : group.getContextsForBus(busNumber)) {
126 hasContext = true;
127 int[] usages = getUsagesForContext(contextNumber);
128 for (int usage : usages) {
129 mixingRuleBuilder.addRule(
130 new AudioAttributes.Builder().setUsage(usage).build(),
131 AudioMixingRule.RULE_MATCH_ATTRIBUTE_USAGE);
132 }
133 Log.d(CarLog.TAG_AUDIO, "Bus number: " + busNumber
134 + " contextNumber: " + contextNumber
135 + " sampleRate: " + info.getSampleRate()
136 + " channels: " + info.getChannelCount()
137 + " usages: " + Arrays.toString(usages));
138 }
139 if (hasContext) {
140 // It's a valid case that an audio output bus is defined in
141 // audio_policy_configuration and no context is assigned to it.
142 // In such case, do not build a policy mix with zero rules.
143 AudioMix audioMix = new AudioMix.Builder(mixingRuleBuilder.build())
144 .setFormat(mixFormat)
145 .setDevice(info.getAudioDeviceInfo())
146 .setRouteFlags(AudioMix.ROUTE_FLAG_RENDER)
147 .build();
148 builder.addMix(audioMix);
149 }
150 }
151 }
152
153 private int[] getUsagesForContext(int contextNumber) {
154 final List usages = new ArrayList<>();
155 for (int i = 0; i < CarAudioDynamicRouting.USAGE_TO_CONTEXT.size(); i++) {
156 if (CarAudioDynamicRouting.USAGE_TO_CONTEXT.valueAt(i) == contextNumber) {
157 usages.add(CarAudioDynamicRouting.USAGE_TO_CONTEXT.keyAt(i));
158 }
159 }
160 return usages.stream().mapToInt(i -> i).toArray();
161 }
162 } 通过contextNumber获取到usages，遍历usages将usage添加到mixingRuleBuilder中，然后再将mixingRuleBuilder添加到AudioMix中，将AudioMix addMix 到AudioPolicy中， 这样usage和device就关联上了。