Effects: add a method to retrieve audio configuration

An effect can be instantiated on different streams,
which affects its configuration. For some audio effects
like Visualizer it's important to know the sampling
rate that the effect operates on. The new method
provides means for retrieving current audio configuration
of the effect.

Bug: 162727518
Test: atest CtsMediaAudioTestCases:VisualizerTest
Change-Id: I2390dd07a67d1eaf4ed92a911d8a2c4b2e083027
diff --git a/services/audioflinger/Effects.cpp b/services/audioflinger/Effects.cpp
index e6d7cf7..72c378d 100644
--- a/services/audioflinger/Effects.cpp
+++ b/services/audioflinger/Effects.cpp
@@ -569,7 +569,8 @@
       mMaxDisableWaitCnt(1), // set by configure(), should be >= 1
       mDisableWaitCnt(0),    // set by process() and updateState()
       mOffloaded(false),
-      mAddedToHal(false)
+      mAddedToHal(false),
+      mIsOutput(false)
 #ifdef FLOAT_EFFECT_CHAIN
       , mSupportsFloat(false)
 #endif
@@ -962,6 +963,7 @@
     mConfig.outputCfg.mask = EFFECT_CONFIG_ALL;
     mConfig.inputCfg.buffer.frameCount = callback->frameCount();
     mConfig.outputCfg.buffer.frameCount = mConfig.inputCfg.buffer.frameCount;
+    mIsOutput = callback->isOutput();
 
     ALOGV("configure() %p chain %p buffer %p framecount %zu",
           this, callback->chain().promote().get(),
@@ -980,7 +982,7 @@
 
 #ifdef MULTICHANNEL_EFFECT_CHAIN
     if (status != NO_ERROR &&
-            callback->isOutput() &&
+            mIsOutput &&
             (mConfig.inputCfg.channels != AUDIO_CHANNEL_OUT_STEREO
                     || mConfig.outputCfg.channels != AUDIO_CHANNEL_OUT_STEREO)) {
         // Older effects may require exact STEREO position mask.
@@ -1643,6 +1645,22 @@
     return status;
 }
 
+status_t AudioFlinger::EffectModule::getConfigs(
+        audio_config_base_t* inputCfg, audio_config_base_t* outputCfg, bool* isOutput) const {
+    Mutex::Autolock _l(mLock);
+    if (mConfig.inputCfg.mask == 0 || mConfig.outputCfg.mask == 0) {
+        return NO_INIT;
+    }
+    inputCfg->sample_rate = mConfig.inputCfg.samplingRate;
+    inputCfg->channel_mask = static_cast<audio_channel_mask_t>(mConfig.inputCfg.channels);
+    inputCfg->format = static_cast<audio_format_t>(mConfig.inputCfg.format);
+    outputCfg->sample_rate = mConfig.outputCfg.samplingRate;
+    outputCfg->channel_mask = static_cast<audio_channel_mask_t>(mConfig.outputCfg.channels);
+    outputCfg->format = static_cast<audio_format_t>(mConfig.outputCfg.format);
+    *isOutput = mIsOutput;
+    return NO_ERROR;
+}
+
 static std::string dumpInOutBuffer(bool isInput, const sp<EffectBufferHalInterface> &buffer) {
     std::stringstream ss;
 
@@ -1760,6 +1778,7 @@
 BINDER_METHOD_ENTRY(command) \
 BINDER_METHOD_ENTRY(disconnect) \
 BINDER_METHOD_ENTRY(getCblk) \
+BINDER_METHOD_ENTRY(getConfig) \
 
 // singleton for Binder Method Statistics for IEffect
 mediautils::MethodStatistics<int>& getIEffectStatistics() {
@@ -1803,6 +1822,13 @@
   *_aidl_return = (code); \
   return Status::ok();
 
+#define VALUE_OR_RETURN_STATUS_AS_OUT(exp)              \
+    ({                                                  \
+        auto _tmp = (exp);                              \
+        if (!_tmp.ok()) { RETURN(_tmp.error()); }       \
+        std::move(_tmp.value());                        \
+    })
+
 Status AudioFlinger::EffectHandle::enable(int32_t* _aidl_return)
 {
     AutoMutex _l(mLock);
@@ -1914,6 +1940,32 @@
     return Status::ok();
 }
 
+Status AudioFlinger::EffectHandle::getConfig(
+        media::EffectConfig* _config, int32_t* _aidl_return) {
+    AutoMutex _l(mLock);
+    sp<EffectBase> effect = mEffect.promote();
+    if (effect == nullptr || mDisconnected) {
+        RETURN(DEAD_OBJECT);
+    }
+    sp<EffectModule> effectModule = effect->asEffectModule();
+    if (effectModule == nullptr) {
+        RETURN(INVALID_OPERATION);
+    }
+    audio_config_base_t inputCfg = AUDIO_CONFIG_BASE_INITIALIZER;
+    audio_config_base_t outputCfg = AUDIO_CONFIG_BASE_INITIALIZER;
+    bool isOutput;
+    status_t status = effectModule->getConfigs(&inputCfg, &outputCfg, &isOutput);
+    if (status == NO_ERROR) {
+        constexpr bool isInput = false; // effects always use 'OUT' channel masks.
+        _config->inputCfg = VALUE_OR_RETURN_STATUS_AS_OUT(
+                legacy2aidl_audio_config_base_t_AudioConfigBase(inputCfg, isInput));
+        _config->outputCfg = VALUE_OR_RETURN_STATUS_AS_OUT(
+                legacy2aidl_audio_config_base_t_AudioConfigBase(outputCfg, isInput));
+        _config->isOnInputStream = !isOutput;
+    }
+    RETURN(status);
+}
+
 Status AudioFlinger::EffectHandle::command(int32_t cmdCode,
                        const std::vector<uint8_t>& cmdData,
                        int32_t maxResponseSize,