diff --git a/libs/gui/Android.bp b/libs/gui/Android.bp
index 19a29c1..fea9f81 100644
--- a/libs/gui/Android.bp
+++ b/libs/gui/Android.bp
@@ -184,7 +184,6 @@
         "IGraphicBufferConsumer.cpp",
         "IGraphicBufferProducer.cpp",
         "IProducerListener.cpp",
-        "IRegionSamplingListener.cpp",
         "ISurfaceComposer.cpp",
         "ISurfaceComposerClient.cpp",
         "ITransactionCompletedListener.cpp",
diff --git a/libs/gui/IRegionSamplingListener.cpp b/libs/gui/IRegionSamplingListener.cpp
deleted file mode 100644
index 40cbfce..0000000
--- a/libs/gui/IRegionSamplingListener.cpp
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * Copyright 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#define LOG_TAG "IRegionSamplingListener"
-//#define LOG_NDEBUG 0
-
-#include <gui/IRegionSamplingListener.h>
-
-namespace android {
-
-namespace { // Anonymous
-
-enum class Tag : uint32_t {
-    ON_SAMPLE_COLLECTED = IBinder::FIRST_CALL_TRANSACTION,
-    LAST = ON_SAMPLE_COLLECTED,
-};
-
-} // Anonymous namespace
-
-class BpRegionSamplingListener : public SafeBpInterface<IRegionSamplingListener> {
-public:
-    explicit BpRegionSamplingListener(const sp<IBinder>& impl)
-          : SafeBpInterface<IRegionSamplingListener>(impl, "BpRegionSamplingListener") {}
-
-    ~BpRegionSamplingListener() override;
-
-    void onSampleCollected(float medianLuma) override {
-        callRemoteAsync<decltype(
-                &IRegionSamplingListener::onSampleCollected)>(Tag::ON_SAMPLE_COLLECTED, medianLuma);
-    }
-};
-
-// Out-of-line virtual method definitions to trigger vtable emission in this translation unit (see
-// clang warning -Wweak-vtables)
-BpRegionSamplingListener::~BpRegionSamplingListener() = default;
-
-IMPLEMENT_META_INTERFACE(RegionSamplingListener, "android.gui.IRegionSamplingListener");
-
-status_t BnRegionSamplingListener::onTransact(uint32_t code, const Parcel& data, Parcel* reply,
-                                              uint32_t flags) {
-    if (code < IBinder::FIRST_CALL_TRANSACTION || code > static_cast<uint32_t>(Tag::LAST)) {
-        return BBinder::onTransact(code, data, reply, flags);
-    }
-    auto tag = static_cast<Tag>(code);
-    switch (tag) {
-        case Tag::ON_SAMPLE_COLLECTED:
-            return callLocalAsync(data, reply, &IRegionSamplingListener::onSampleCollected);
-    }
-}
-
-} // namespace android
diff --git a/libs/gui/ISurfaceComposer.cpp b/libs/gui/ISurfaceComposer.cpp
index 0295099..a90f755 100644
--- a/libs/gui/ISurfaceComposer.cpp
+++ b/libs/gui/ISurfaceComposer.cpp
@@ -17,13 +17,13 @@
 // tag as surfaceflinger
 #define LOG_TAG "SurfaceFlinger"
 
+#include <android/gui/IRegionSamplingListener.h>
 #include <android/gui/ITransactionTraceListener.h>
 #include <binder/IPCThreadState.h>
 #include <binder/IServiceManager.h>
 #include <binder/Parcel.h>
 #include <gui/IDisplayEventConnection.h>
 #include <gui/IGraphicBufferProducer.h>
-#include <gui/IRegionSamplingListener.h>
 #include <gui/ISurfaceComposer.h>
 #include <gui/ISurfaceComposerClient.h>
 #include <gui/LayerDebugInfo.h>
@@ -44,6 +44,7 @@
 
 namespace android {
 
+using gui::IRegionSamplingListener;
 using gui::IWindowInfosListener;
 using ui::ColorMode;
 
diff --git a/libs/gui/SurfaceComposerClient.cpp b/libs/gui/SurfaceComposerClient.cpp
index b139cf1..f6253a2 100644
--- a/libs/gui/SurfaceComposerClient.cpp
+++ b/libs/gui/SurfaceComposerClient.cpp
@@ -53,6 +53,7 @@
 namespace android {
 
 using gui::FocusRequest;
+using gui::IRegionSamplingListener;
 using gui::WindowInfo;
 using gui::WindowInfoHandle;
 using gui::WindowInfosListener;
diff --git a/libs/gui/aidl/android/gui/IRegionSamplingListener.aidl b/libs/gui/aidl/android/gui/IRegionSamplingListener.aidl
new file mode 100644
index 0000000..00a3959
--- /dev/null
+++ b/libs/gui/aidl/android/gui/IRegionSamplingListener.aidl
@@ -0,0 +1,22 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.gui;
+
+/** @hide */
+oneway interface IRegionSamplingListener {
+    void onSampleCollected(float medianLuma);
+}
diff --git a/libs/gui/include/gui/IRegionSamplingListener.h b/libs/gui/include/gui/IRegionSamplingListener.h
deleted file mode 100644
index 1803d9a..0000000
--- a/libs/gui/include/gui/IRegionSamplingListener.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#pragma once
-
-#include <cstdint>
-#include <vector>
-
-#include <binder/IInterface.h>
-#include <binder/SafeInterface.h>
-
-namespace android {
-
-class IRegionSamplingListener : public IInterface {
-public:
-    DECLARE_META_INTERFACE(RegionSamplingListener)
-
-    virtual void onSampleCollected(float medianLuma) = 0;
-};
-
-class BnRegionSamplingListener : public SafeBnInterface<IRegionSamplingListener> {
-public:
-    BnRegionSamplingListener()
-          : SafeBnInterface<IRegionSamplingListener>("BnRegionSamplingListener") {}
-
-    status_t onTransact(uint32_t code, const Parcel& data, Parcel* reply,
-                        uint32_t flags = 0) override;
-};
-
-} // namespace android
diff --git a/libs/gui/include/gui/ISurfaceComposer.h b/libs/gui/include/gui/ISurfaceComposer.h
index e0183ad..e1e9182 100644
--- a/libs/gui/include/gui/ISurfaceComposer.h
+++ b/libs/gui/include/gui/ISurfaceComposer.h
@@ -19,6 +19,7 @@
 #include <android/gui/DisplayBrightness.h>
 #include <android/gui/IFpsListener.h>
 #include <android/gui/IHdrLayerInfoListener.h>
+#include <android/gui/IRegionSamplingListener.h>
 #include <android/gui/IScreenCaptureListener.h>
 #include <android/gui/ITransactionTraceListener.h>
 #include <android/gui/ITunnelModeEnabledListener.h>
@@ -63,10 +64,10 @@
 class IDisplayEventConnection;
 class IGraphicBufferProducer;
 class ISurfaceComposerClient;
-class IRegionSamplingListener;
 class Rect;
 enum class FrameEvent;
 
+using gui::IRegionSamplingListener;
 using gui::IScreenCaptureListener;
 
 namespace ui {
diff --git a/libs/gui/include/gui/SurfaceComposerClient.h b/libs/gui/include/gui/SurfaceComposerClient.h
index e05c364..0fe1253 100644
--- a/libs/gui/include/gui/SurfaceComposerClient.h
+++ b/libs/gui/include/gui/SurfaceComposerClient.h
@@ -51,10 +51,11 @@
 class HdrCapabilities;
 class ISurfaceComposerClient;
 class IGraphicBufferProducer;
-class IRegionSamplingListener;
 class ITunnelModeEnabledListener;
 class Region;
 
+using gui::IRegionSamplingListener;
+
 struct SurfaceControlStats {
     SurfaceControlStats(const sp<SurfaceControl>& sc, nsecs_t latchTime, nsecs_t acquireTime,
                         const sp<Fence>& presentFence, const sp<Fence>& prevReleaseFence,
diff --git a/libs/gui/tests/RegionSampling_test.cpp b/libs/gui/tests/RegionSampling_test.cpp
index 6746b0a..c9106be 100644
--- a/libs/gui/tests/RegionSampling_test.cpp
+++ b/libs/gui/tests/RegionSampling_test.cpp
@@ -17,9 +17,9 @@
 #include <gtest/gtest.h>
 #include <thread>
 
+#include <android/gui/BnRegionSamplingListener.h>
 #include <binder/ProcessState.h>
 #include <gui/DisplayEventReceiver.h>
-#include <gui/IRegionSamplingListener.h>
 #include <gui/ISurfaceComposer.h>
 #include <gui/Surface.h>
 #include <gui/SurfaceComposerClient.h>
@@ -135,12 +135,13 @@
     std::atomic<bool> poll_{true};
 };
 
-struct Listener : BnRegionSamplingListener {
-    void onSampleCollected(float medianLuma) override {
+struct Listener : android::gui::BnRegionSamplingListener {
+    binder::Status onSampleCollected(float medianLuma) override {
         std::unique_lock<decltype(mutex)> lk(mutex);
         received = true;
         mLuma = medianLuma;
         cv.notify_all();
+        return binder::Status::ok();
     };
     bool wait_event(std::chrono::milliseconds timeout) {
         std::unique_lock<decltype(mutex)> lk(mutex);
diff --git a/libs/gui/tests/SamplingDemo.cpp b/libs/gui/tests/SamplingDemo.cpp
index 0cd150d..a083a22 100644
--- a/libs/gui/tests/SamplingDemo.cpp
+++ b/libs/gui/tests/SamplingDemo.cpp
@@ -20,9 +20,9 @@
 #include <chrono>
 #include <thread>
 
+#include <android/gui/BnRegionSamplingListener.h>
 #include <binder/IPCThreadState.h>
 #include <binder/ProcessState.h>
-#include <gui/IRegionSamplingListener.h>
 #include <gui/ISurfaceComposer.h>
 #include <gui/SurfaceComposerClient.h>
 #include <gui/SurfaceControl.h>
@@ -33,7 +33,7 @@
 
 namespace android {
 
-class Button : public BnRegionSamplingListener {
+class Button : public gui::BnRegionSamplingListener {
 public:
     Button(const char* name, const Rect& samplingArea) {
         sp<SurfaceComposerClient> client = new SurfaceComposerClient;
@@ -99,9 +99,10 @@
                 .apply();
     }
 
-    void onSampleCollected(float medianLuma) override {
+    binder::Status onSampleCollected(float medianLuma) override {
         ATRACE_CALL();
         setColor(medianLuma);
+        return binder::Status::ok();
     }
 
     sp<SurfaceComposerClient> mClient;
diff --git a/libs/gui/tests/Surface_test.cpp b/libs/gui/tests/Surface_test.cpp
index b2baea6..e0c2aa7 100644
--- a/libs/gui/tests/Surface_test.cpp
+++ b/libs/gui/tests/Surface_test.cpp
@@ -45,6 +45,7 @@
 // retrieve wide-color and hdr settings from configstore
 using namespace android::hardware::configstore;
 using namespace android::hardware::configstore::V1_0;
+using gui::IRegionSamplingListener;
 using ui::ColorMode;
 
 using Transaction = SurfaceComposerClient::Transaction;