Enable passthrough mode by default for audio, soundtrigger, and radio

Remove ENABLE_TREBLE flag usage for legacy hal fallback.
Introduce new build flag USE_LEGACY_LOCAL_AUDIO_HAL for fallback.

Bug: 32978887
Test: checked "OK Google" (from standby), Hangouts, YouTube,
      Play Music, fake radio hal + test app
KI: issues when using equializer and virtualuzer in Play Music

Change-Id: I1c279e622c885f799481f1287e0660ca576fcea0
diff --git a/media/libaudiohal/Android.mk b/media/libaudiohal/Android.mk
index deb26b5..58b38a6 100644
--- a/media/libaudiohal/Android.mk
+++ b/media/libaudiohal/Android.mk
@@ -9,9 +9,20 @@
     liblog      \
     libutils
 
-ifeq ($(ENABLE_TREBLE), true)
+ifeq ($(USE_LEGACY_LOCAL_AUDIO_HAL), true)
 
-LOCAL_CFLAGS += -DENABLE_TREBLE
+# Use audiohal directly w/o hwbinder middleware.
+# This is for performance comparison and debugging only.
+
+LOCAL_SRC_FILES := \
+    DeviceHalLocal.cpp          \
+    DevicesFactoryHalLocal.cpp  \
+    EffectBufferHalLocal.cpp    \
+    EffectHalLocal.cpp          \
+    EffectsFactoryHalLocal.cpp  \
+    StreamHalLocal.cpp
+
+else  # if !USE_LEGACY_LOCAL_AUDIO_HAL
 
 LOCAL_SRC_FILES := \
     ConversionHelperHidl.cpp   \
@@ -36,16 +47,7 @@
     android.hidl.memory@1.0                \
     libmedia_helper
 
-else  # if !ENABLE_TREBLE
-
-LOCAL_SRC_FILES := \
-    DeviceHalLocal.cpp          \
-    DevicesFactoryHalLocal.cpp  \
-    EffectBufferHalLocal.cpp    \
-    EffectHalLocal.cpp          \
-    EffectsFactoryHalLocal.cpp  \
-    StreamHalLocal.cpp
-endif  # ENABLE_TREBLE
+endif  # USE_LEGACY_LOCAL_AUDIO_HAL
 
 LOCAL_MODULE := libaudiohal
 
diff --git a/media/libaudiohal/EffectHalHidl.cpp b/media/libaudiohal/EffectHalHidl.cpp
index f1f3f2a..3fb2f43 100644
--- a/media/libaudiohal/EffectHalHidl.cpp
+++ b/media/libaudiohal/EffectHalHidl.cpp
@@ -167,14 +167,16 @@
         uint32_t *replySize, void *pReplyData) {
     if (mEffect == 0) return NO_INIT;
     hidl_vec<uint8_t> hidlData;
-    hidlData.setToExternal(reinterpret_cast<uint8_t*>(pCmdData), cmdSize);
+    if (pCmdData != nullptr && cmdSize > 0) {
+        hidlData.setToExternal(reinterpret_cast<uint8_t*>(pCmdData), cmdSize);
+    }
     status_t status;
     Return<void> ret = mEffect->command(cmdCode, hidlData, *replySize,
             [&](int32_t s, const hidl_vec<uint8_t>& result) {
                 status = s;
                 if (status == 0) {
                     if (*replySize > result.size()) *replySize = result.size();
-                    if (pReplyData && *replySize > 0) {
+                    if (pReplyData != nullptr && *replySize > 0) {
                         memcpy(pReplyData, &result[0], *replySize);
                     }
                 }