audio: Exported recommendedMuteDurationMs for output profiles

- Added muteDuration to customize mute duration while switching device's
path to avoid truncated sound at beginning.
- Muted duration will be replaced only when there are defined duration
in audio_policy_configuration.xml.

Bug: 183344508
Test: manual audio test with different audio_policy_configuration.xml,
which is with/without muteDuration definition.

Signed-off-by: Jasmine Cha <chajasmine@google.com>
Change-Id: Idced0e256a6b8e91ba2704c5ad89fbf8aba62bf5
diff --git a/services/audiopolicy/common/managerdefinitions/include/AudioOutputDescriptor.h b/services/audiopolicy/common/managerdefinitions/include/AudioOutputDescriptor.h
index 7c7f02d..123011a 100644
--- a/services/audiopolicy/common/managerdefinitions/include/AudioOutputDescriptor.h
+++ b/services/audiopolicy/common/managerdefinitions/include/AudioOutputDescriptor.h
@@ -307,6 +307,8 @@
     DeviceVector mDevices; /**< current devices this output is routed to */
     wp<AudioPolicyMix> mPolicyMix;  // non NULL when used by a dynamic policy
 
+    virtual uint32_t getRecommendedMuteDurationMs() const { return 0; }
+
 protected:
     const sp<PolicyAudioPort> mPolicyAudioPort;
     AudioPolicyClientInterface * const mClientInterface;
@@ -415,6 +417,8 @@
      */
     DeviceVector filterSupportedDevices(const DeviceVector &devices) const;
 
+    uint32_t getRecommendedMuteDurationMs() const override;
+
     const sp<IOProfile> mProfile;          // I/O profile this output derives from
     audio_io_handle_t mIoHandle;           // output handle
     uint32_t mLatency;                  //
diff --git a/services/audiopolicy/common/managerdefinitions/include/IOProfile.h b/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
index a74cefa..81828ed 100644
--- a/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
+++ b/services/audiopolicy/common/managerdefinitions/include/IOProfile.h
@@ -207,6 +207,8 @@
     // Number of streams currently active for this profile. This is not the number of active clients
     // (AudioTrack or AudioRecord) but the number of active HAL streams.
     uint32_t     curActiveCount;
+    // Mute duration while changing device on this output profile.
+    uint32_t     recommendedMuteDurationMs = 0;
 
 private:
     DeviceVector mSupportedDevices; // supported devices: this input/output can be routed from/to
diff --git a/services/audiopolicy/common/managerdefinitions/src/AudioOutputDescriptor.cpp b/services/audiopolicy/common/managerdefinitions/src/AudioOutputDescriptor.cpp
index f3d2326..34b5c1a 100644
--- a/services/audiopolicy/common/managerdefinitions/src/AudioOutputDescriptor.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/AudioOutputDescriptor.cpp
@@ -670,6 +670,15 @@
     return NO_ERROR;
 }
 
+uint32_t SwAudioOutputDescriptor::getRecommendedMuteDurationMs() const
+{
+    if (isDuplicated()) {
+        return std::max(mOutput1->getRecommendedMuteDurationMs(),
+                mOutput2->getRecommendedMuteDurationMs());
+    }
+    return mProfile->recommendedMuteDurationMs;
+}
+
 // HwAudioOutputDescriptor implementation
 HwAudioOutputDescriptor::HwAudioOutputDescriptor(const sp<SourceClientDescriptor>& source,
                                                  AudioPolicyClientInterface *clientInterface)
diff --git a/services/audiopolicy/common/managerdefinitions/src/IOProfile.cpp b/services/audiopolicy/common/managerdefinitions/src/IOProfile.cpp
index 09b614d..624ad95 100644
--- a/services/audiopolicy/common/managerdefinitions/src/IOProfile.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/IOProfile.cpp
@@ -137,6 +137,7 @@
              maxOpenCount, curOpenCount);
     dst->appendFormat("    - maxActiveCount: %u - curActiveCount: %u\n",
              maxActiveCount, curActiveCount);
+    dst->appendFormat("    - recommendedMuteDurationMs: %u ms\n", recommendedMuteDurationMs);
 }
 
 void IOProfile::log()
diff --git a/services/audiopolicy/common/managerdefinitions/src/Serializer.cpp b/services/audiopolicy/common/managerdefinitions/src/Serializer.cpp
index 84ed656..4dfef73 100644
--- a/services/audiopolicy/common/managerdefinitions/src/Serializer.cpp
+++ b/services/audiopolicy/common/managerdefinitions/src/Serializer.cpp
@@ -123,6 +123,7 @@
         static constexpr const char *flags = "flags";
         static constexpr const char *maxOpenCount = "maxOpenCount";
         static constexpr const char *maxActiveCount = "maxActiveCount";
+        static constexpr const char *recommendedMuteDurationMs = "recommendedMuteDurationMs";
     };
 
     // Children: GainTraits
@@ -496,6 +497,13 @@
     if (!maxActiveCount.empty()) {
         convertTo(maxActiveCount, mixPort->maxActiveCount);
     }
+
+    std::string recommendedmuteDurationMsLiteral =
+            getXmlAttribute(child, Attributes::recommendedMuteDurationMs);
+    if (!recommendedmuteDurationMsLiteral.empty()) {
+        convertTo(recommendedmuteDurationMsLiteral, mixPort->recommendedMuteDurationMs);
+    }
+
     // Deserialize children
     AudioGainTraits::Collection gains;
     status = deserializeCollection<AudioGainTraits>(child, &gains, NULL);
diff --git a/services/audiopolicy/managerdefault/AudioPolicyManager.cpp b/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
index 6f87bf0..87f4694 100644
--- a/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
+++ b/services/audiopolicy/managerdefault/AudioPolicyManager.cpp
@@ -6294,11 +6294,18 @@
     // different per device volumes
     if (outputDesc->isActive() && (devices != prevDevices)) {
         uint32_t tempMuteWaitMs = outputDesc->latency() * 2;
-        // temporary mute duration is conservatively set to 4 times the reported latency
-        uint32_t tempMuteDurationMs = outputDesc->latency() * 4;
+
         if (muteWaitMs < tempMuteWaitMs) {
             muteWaitMs = tempMuteWaitMs;
         }
+
+        // If recommended duration is defined, replace temporary mute duration to avoid
+        // truncated notifications at beginning, which depends on duration of changing path in HAL.
+        // Otherwise, temporary mute duration is conservatively set to 4 times the reported latency.
+        uint32_t tempRecommendedMuteDuration = outputDesc->getRecommendedMuteDurationMs();
+        uint32_t tempMuteDurationMs = tempRecommendedMuteDuration > 0 ?
+                tempRecommendedMuteDuration : outputDesc->latency() * 4;
+
         for (const auto &activeVs : outputDesc->getActiveVolumeSources()) {
             // make sure that we do not start the temporary mute period too early in case of
             // delayed device change