diff --git a/include/media/omx/1.0/Conversion.h b/include/media/omx/1.0/Conversion.h
index ee83713..f3f8441 100644
--- a/include/media/omx/1.0/Conversion.h
+++ b/include/media/omx/1.0/Conversion.h
@@ -191,6 +191,19 @@
 }
 
 /**
+ * \brief Convert `Return<Status>` to `binder::Status`.
+ *
+ * \param[in] t The source `Return<Status>`.
+ * \return The corresponding `binder::Status`.
+ */
+// convert: Return<Status> -> ::android::binder::Status
+inline ::android::binder::Status toBinderStatus(
+        Return<Status> const& t) {
+    return ::android::binder::Status::fromStatusT(
+            t.isOk() ? static_cast<status_t>(static_cast<Status>(t)) : UNKNOWN_ERROR);
+}
+
+/**
  * \brief Convert `Return<Status>` to `status_t`. This is for legacy binder
  * calls.
  *
diff --git a/include/media/omx/1.0/WGraphicBufferSource.h b/include/media/omx/1.0/WGraphicBufferSource.h
index 7c80c2e..0ca5f44 100644
--- a/include/media/omx/1.0/WGraphicBufferSource.h
+++ b/include/media/omx/1.0/WGraphicBufferSource.h
@@ -48,7 +48,6 @@
 using ::android::hardware::Return;
 using ::android::hardware::Void;
 using ::android::sp;
-
 using ::android::IOMXNode;
 
 /**
@@ -60,7 +59,7 @@
  * - TW = Treble Wrapper --- It wraps a legacy object inside a Treble object.
  */
 
-typedef ::android::IGraphicBufferSource LGraphicBufferSource;
+typedef ::android::binder::Status BnStatus;
 typedef ::android::BnGraphicBufferSource BnGraphicBufferSource;
 typedef ::android::hardware::media::omx::V1_0::IGraphicBufferSource
         TGraphicBufferSource;
@@ -68,36 +67,19 @@
 struct LWGraphicBufferSource : public BnGraphicBufferSource {
     sp<TGraphicBufferSource> mBase;
     LWGraphicBufferSource(sp<TGraphicBufferSource> const& base);
-    ::android::binder::Status configure(
+    BnStatus configure(
             const sp<IOMXNode>& omxNode, int32_t dataSpace) override;
-    ::android::binder::Status setSuspend(bool suspend, int64_t timeUs) override;
-    ::android::binder::Status setRepeatPreviousFrameDelayUs(
+    BnStatus setSuspend(bool suspend, int64_t timeUs) override;
+    BnStatus setRepeatPreviousFrameDelayUs(
             int64_t repeatAfterUs) override;
-    ::android::binder::Status setMaxFps(float maxFps) override;
-    ::android::binder::Status setTimeLapseConfig(
+    BnStatus setMaxFps(float maxFps) override;
+    BnStatus setTimeLapseConfig(
             int64_t timePerFrameUs, int64_t timePerCaptureUs) override;
-    ::android::binder::Status setStartTimeUs(int64_t startTimeUs) override;
-    ::android::binder::Status setStopTimeUs(int64_t stopTimeUs) override;
-    ::android::binder::Status setColorAspects(int32_t aspects) override;
-    ::android::binder::Status setTimeOffsetUs(int64_t timeOffsetsUs) override;
-    ::android::binder::Status signalEndOfInputStream() override;
-};
-
-struct TWGraphicBufferSource : public TGraphicBufferSource {
-    sp<LGraphicBufferSource> mBase;
-    TWGraphicBufferSource(sp<LGraphicBufferSource> const& base);
-    Return<void> configure(
-            const sp<IOmxNode>& omxNode, Dataspace dataspace) override;
-    Return<void> setSuspend(bool suspend, int64_t timeUs) override;
-    Return<void> setRepeatPreviousFrameDelayUs(int64_t repeatAfterUs) override;
-    Return<void> setMaxFps(float maxFps) override;
-    Return<void> setTimeLapseConfig(
-            int64_t timePerFrameUs, int64_t timePerCaptureUs) override;
-    Return<void> setStartTimeUs(int64_t startTimeUs) override;
-    Return<void> setStopTimeUs(int64_t stopTimeUs) override;
-    Return<void> setColorAspects(const ColorAspects& aspects) override;
-    Return<void> setTimeOffsetUs(int64_t timeOffsetUs) override;
-    Return<void> signalEndOfInputStream() override;
+    BnStatus setStartTimeUs(int64_t startTimeUs) override;
+    BnStatus setStopTimeUs(int64_t stopTimeUs) override;
+    BnStatus setColorAspects(int32_t aspects) override;
+    BnStatus setTimeOffsetUs(int64_t timeOffsetsUs) override;
+    BnStatus signalEndOfInputStream() override;
 };
 
 }  // namespace utils
diff --git a/include/media/omx/1.0/WOmx.h b/include/media/omx/1.0/WOmx.h
index 4aaf470..9268bd6 100644
--- a/include/media/omx/1.0/WOmx.h
+++ b/include/media/omx/1.0/WOmx.h
@@ -70,18 +70,6 @@
             sp<::android::IGraphicBufferSource>* bufferSource) override;
 };
 
-struct TWOmx : public IOmx {
-    sp<IOMX> mBase;
-    TWOmx(sp<IOMX> const& base);
-    Return<void> listNodes(listNodes_cb _hidl_cb) override;
-    Return<void> allocateNode(
-            const hidl_string& name,
-            const sp<IOmxObserver>& observer,
-            allocateNode_cb _hidl_cb) override;
-    Return<void> createInputSurface(createInputSurface_cb _hidl_cb) override;
-
-};
-
 }  // namespace utils
 }  // namespace V1_0
 }  // namespace omx