diff --git a/media/libaudiohal/EffectsFactoryHalInterface.cpp b/media/libaudiohal/EffectsFactoryHalInterface.cpp
index e21c235..bd3ef61 100644
--- a/media/libaudiohal/EffectsFactoryHalInterface.cpp
+++ b/media/libaudiohal/EffectsFactoryHalInterface.cpp
@@ -25,13 +25,13 @@
 // static
 sp<EffectsFactoryHalInterface> EffectsFactoryHalInterface::create() {
     if (hardware::audio::effect::V5_0::IEffectsFactory::getService() != nullptr) {
-        return V5_0::createEffectsFactoryHal();
+        return effect::V5_0::createEffectsFactoryHal();
     }
     if (hardware::audio::effect::V4_0::IEffectsFactory::getService() != nullptr) {
-        return V4_0::createEffectsFactoryHal();
+        return effect::V4_0::createEffectsFactoryHal();
     }
     if (hardware::audio::effect::V2_0::IEffectsFactory::getService() != nullptr) {
-        return V2_0::createEffectsFactoryHal();
+        return effect::V2_0::createEffectsFactoryHal();
     }
     return nullptr;
 }
diff --git a/media/libaudiohal/impl/EffectBufferHalHidl.cpp b/media/libaudiohal/impl/EffectBufferHalHidl.cpp
index 6ef4e8a..5367972 100644
--- a/media/libaudiohal/impl/EffectBufferHalHidl.cpp
+++ b/media/libaudiohal/impl/EffectBufferHalHidl.cpp
@@ -30,6 +30,7 @@
 using ::android::hidl::allocator::V1_0::IAllocator;
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
 // static
@@ -142,5 +143,6 @@
     memcpy(mExternalData, mAudioBuffer.raw, size);
 }
 
+} // namespace effect
 } // namespace CPP_VERSION
 } // namespace android
diff --git a/media/libaudiohal/impl/EffectBufferHalHidl.h b/media/libaudiohal/impl/EffectBufferHalHidl.h
index 0c99a02..4826813 100644
--- a/media/libaudiohal/impl/EffectBufferHalHidl.h
+++ b/media/libaudiohal/impl/EffectBufferHalHidl.h
@@ -23,13 +23,15 @@
 #include <media/audiohal/EffectBufferHalInterface.h>
 #include <system/audio_effect.h>
 
-using android::hardware::audio::effect::CPP_VERSION::AudioBuffer;
 using android::hardware::hidl_memory;
 using android::hidl::memory::V1_0::IMemory;
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
+using namespace ::android::hardware::audio::effect::CPP_VERSION;
+
 class EffectBufferHalHidl : public EffectBufferHalInterface
 {
   public:
@@ -73,6 +75,7 @@
 };
 
 } // namespace CPP_VERSION
+} // namespace effect
 } // namespace android
 
 #endif // ANDROID_HARDWARE_EFFECT_BUFFER_HAL_HIDL_H
diff --git a/media/libaudiohal/impl/EffectHalHidl.cpp b/media/libaudiohal/impl/EffectHalHidl.cpp
index df79b95..b0597b3 100644
--- a/media/libaudiohal/impl/EffectHalHidl.cpp
+++ b/media/libaudiohal/impl/EffectHalHidl.cpp
@@ -26,11 +26,6 @@
 #include "EffectHalHidl.h"
 #include "HidlUtils.h"
 
-using ::android::hardware::audio::effect::CPP_VERSION::AudioBuffer;
-using ::android::hardware::audio::effect::CPP_VERSION::EffectBufferAccess;
-using ::android::hardware::audio::effect::CPP_VERSION::EffectConfigParameters;
-using ::android::hardware::audio::effect::CPP_VERSION::MessageQueueFlagBits;
-using ::android::hardware::audio::effect::CPP_VERSION::Result;
 using ::android::hardware::audio::common::CPP_VERSION::implementation::HidlUtils;
 using ::android::hardware::audio::common::utils::EnumBitfield;
 using ::android::hardware::hidl_vec;
@@ -38,9 +33,11 @@
 using ::android::hardware::Return;
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
 using namespace ::android::hardware::audio::common::CPP_VERSION;
+using namespace ::android::hardware::audio::effect::CPP_VERSION;
 
 EffectHalHidl::EffectHalHidl(const sp<IEffect>& effect, uint64_t effectId)
         : mEffect(effect), mEffectId(effectId), mBuffersChanged(true), mEfGroup(nullptr) {
@@ -338,4 +335,5 @@
 }
 
 } // namespace CPP_VERSION
+} // namespace effect
 } // namespace android
diff --git a/media/libaudiohal/impl/EffectHalHidl.h b/media/libaudiohal/impl/EffectHalHidl.h
index cd447ff..9d9f707 100644
--- a/media/libaudiohal/impl/EffectHalHidl.h
+++ b/media/libaudiohal/impl/EffectHalHidl.h
@@ -23,17 +23,15 @@
 #include <fmq/MessageQueue.h>
 #include <system/audio_effect.h>
 
-using ::android::hardware::audio::effect::CPP_VERSION::EffectBufferConfig;
-using ::android::hardware::audio::effect::CPP_VERSION::EffectConfig;
-using ::android::hardware::audio::effect::CPP_VERSION::EffectDescriptor;
-using ::android::hardware::audio::effect::CPP_VERSION::IEffect;
-using EffectResult = ::android::hardware::audio::effect::CPP_VERSION::Result;
 using ::android::hardware::EventFlag;
 using ::android::hardware::MessageQueue;
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
+using namespace ::android::hardware::audio::effect::CPP_VERSION;
+
 class EffectHalHidl : public EffectHalInterface
 {
   public:
@@ -70,7 +68,7 @@
 
   private:
     friend class EffectsFactoryHalHidl;
-    typedef MessageQueue<EffectResult, hardware::kSynchronizedReadWrite> StatusMQ;
+    typedef MessageQueue<Result, hardware::kSynchronizedReadWrite> StatusMQ;
 
     sp<IEffect> mEffect;
     const uint64_t mEffectId;
@@ -80,7 +78,7 @@
     std::unique_ptr<StatusMQ> mStatusMQ;
     EventFlag* mEfGroup;
 
-    static status_t analyzeResult(const EffectResult& result);
+    static status_t analyzeResult(const Result& result);
     static void effectBufferConfigFromHal(
             const buffer_config_t& halConfig, EffectBufferConfig* config);
     static void effectBufferConfigToHal(
@@ -105,6 +103,7 @@
 };
 
 } // namespace CPP_VERSION
+} // namespace effect
 } // namespace android
 
 #endif // ANDROID_HARDWARE_EFFECT_HAL_HIDL_H
diff --git a/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp b/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
index 7fea466..7fd6bde 100644
--- a/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
+++ b/media/libaudiohal/impl/EffectsFactoryHalHidl.cpp
@@ -26,14 +26,14 @@
 #include "HidlUtils.h"
 
 using ::android::hardware::audio::common::CPP_VERSION::implementation::HidlUtils;
-using ::android::hardware::audio::effect::CPP_VERSION::IEffect;
-using ::android::hardware::audio::effect::CPP_VERSION::Result;
 using ::android::hardware::Return;
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
 using namespace ::android::hardware::audio::common::CPP_VERSION;
+using namespace ::android::hardware::audio::effect::CPP_VERSION;
 
 EffectsFactoryHalHidl::EffectsFactoryHalHidl() : ConversionHelperHidl("EffectsFactory") {
     mEffectsFactory = IEffectsFactory::getService();
@@ -145,6 +145,6 @@
     return EffectBufferHalHidl::mirror(external, size, buffer);
 }
 
-
 } // namespace CPP_VERSION
+} // namespace effect
 } // namespace android
diff --git a/media/libaudiohal/impl/EffectsFactoryHalHidl.h b/media/libaudiohal/impl/EffectsFactoryHalHidl.h
index 7027153..01178ff 100644
--- a/media/libaudiohal/impl/EffectsFactoryHalHidl.h
+++ b/media/libaudiohal/impl/EffectsFactoryHalHidl.h
@@ -24,11 +24,12 @@
 #include "ConversionHelperHidl.h"
 
 namespace android {
+namespace effect {
 namespace CPP_VERSION {
 
-using ::android::hardware::audio::effect::CPP_VERSION::EffectDescriptor;
-using ::android::hardware::audio::effect::CPP_VERSION::IEffectsFactory;
 using ::android::hardware::hidl_vec;
+using ::android::CPP_VERSION::ConversionHelperHidl;
+using namespace ::android::hardware::audio::effect::CPP_VERSION;
 
 class EffectsFactoryHalHidl : public EffectsFactoryHalInterface, public ConversionHelperHidl
 {
@@ -70,6 +71,7 @@
 }
 
 } // namespace CPP_VERSION
+} // namespace effect
 } // namespace android
 
 #endif // ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
diff --git a/media/libaudiohal/impl/StreamHalHidl.cpp b/media/libaudiohal/impl/StreamHalHidl.cpp
index 9765f1e..c12b362 100644
--- a/media/libaudiohal/impl/StreamHalHidl.cpp
+++ b/media/libaudiohal/impl/StreamHalHidl.cpp
@@ -35,6 +35,7 @@
 namespace android {
 namespace CPP_VERSION {
 
+using EffectHalHidl = ::android::effect::CPP_VERSION::EffectHalHidl;
 using ReadCommand = ::android::hardware::audio::CPP_VERSION::IStreamIn::ReadCommand;
 
 using namespace ::android::hardware::audio::common::CPP_VERSION;
diff --git a/media/libaudiohal/impl/include/libaudiohal/FactoryHalHidl.h b/media/libaudiohal/impl/include/libaudiohal/FactoryHalHidl.h
index 1d912a0..c7319d0 100644
--- a/media/libaudiohal/impl/include/libaudiohal/FactoryHalHidl.h
+++ b/media/libaudiohal/impl/include/libaudiohal/FactoryHalHidl.h
@@ -25,18 +25,29 @@
 
 namespace android {
 
+namespace effect {
 namespace V2_0 {
 sp<EffectsFactoryHalInterface> createEffectsFactoryHal();
-sp<DevicesFactoryHalInterface> createDevicesFactoryHal();
 } // namespace V2_0
 
 namespace V4_0 {
 sp<EffectsFactoryHalInterface> createEffectsFactoryHal();
-sp<DevicesFactoryHalInterface> createDevicesFactoryHal();
 } // namespace V4_0
 
 namespace V5_0 {
 sp<EffectsFactoryHalInterface> createEffectsFactoryHal();
+} // namespace V5_0
+} // namespace effect
+
+namespace V2_0 {
+sp<DevicesFactoryHalInterface> createDevicesFactoryHal();
+} // namespace V2_0
+
+namespace V4_0 {
+sp<DevicesFactoryHalInterface> createDevicesFactoryHal();
+} // namespace V4_0
+
+namespace V5_0 {
 sp<DevicesFactoryHalInterface> createDevicesFactoryHal();
 } // namespace V5_0