Fix ConversionUtil AudioFormat construction

Properly construct AudioFormat when the format passed from the HAL
is null.

Test: atest ConversionUtilTests
Fixes: 272616167
Change-Id: If48f80a02ab733926028363a39f82dd9d1a1ddcf
diff --git a/core/java/android/hardware/soundtrigger/ConversionUtil.java b/core/java/android/hardware/soundtrigger/ConversionUtil.java
index 9a2cd06..be57bbe 100644
--- a/core/java/android/hardware/soundtrigger/ConversionUtil.java
+++ b/core/java/android/hardware/soundtrigger/ConversionUtil.java
@@ -41,7 +41,7 @@
 import java.util.UUID;
 
 /** @hide */
-class ConversionUtil {
+public class ConversionUtil {
     public static SoundTrigger.ModuleProperties aidl2apiModuleDescriptor(
             SoundTriggerModuleDescriptor aidlDesc) {
         Properties properties = aidlDesc.properties;
@@ -233,7 +233,11 @@
         if (audioConfig != null) {
             return AidlConversion.aidl2api_AudioConfig_AudioFormat(audioConfig, isInput);
         }
-        return new AudioFormat.Builder().build();
+        return new AudioFormat.Builder()
+            .setSampleRate(48000)
+            .setEncoding(AudioFormat.ENCODING_PCM_16BIT)
+            .setChannelMask(AudioFormat.CHANNEL_IN_MONO)
+            .build();
     }
 
     public static int api2aidlModelParameter(int apiParam) {
diff --git a/services/tests/voiceinteractiontests/src/com/android/server/soundtrigger_middleware/ConversionUtilTest.java b/services/tests/voiceinteractiontests/src/com/android/server/soundtrigger_middleware/ConversionUtilTest.java
index 5a2ce45..0799859 100644
--- a/services/tests/voiceinteractiontests/src/com/android/server/soundtrigger_middleware/ConversionUtilTest.java
+++ b/services/tests/voiceinteractiontests/src/com/android/server/soundtrigger_middleware/ConversionUtilTest.java
@@ -16,7 +16,10 @@
 
 package com.android.server.soundtrigger_middleware;
 
+import static android.hardware.soundtrigger.ConversionUtil.aidl2apiAudioFormatWithDefault;
+
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 
 import android.hardware.audio.common.V2_0.Uuid;
 
@@ -44,4 +47,14 @@
         Uuid reconstructed = ConversionUtil.aidl2hidlUuid(aidl);
         assertEquals(hidl, reconstructed);
     }
+
+    @Test
+    public void testDefaultAudioFormatConstruction() {
+        // This method should generate a real format when passed null
+        final var format = aidl2apiAudioFormatWithDefault(
+                null /** exercise default **/,
+                true /** isInput **/
+                );
+        assertNotNull(format);
+    }
 }