diff --git a/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IComponent.aidl b/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IComponent.aidl
index 1af66d0..c7d8a97 100644
--- a/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IComponent.aidl
+++ b/media/c2/aidl/aidl_api/android.hardware.media.c2/current/android/hardware/media/c2/IComponent.aidl
@@ -35,7 +35,7 @@
 @VintfStability
 interface IComponent {
   android.hardware.common.NativeHandle configureVideoTunnel(in int avSyncHwId);
-  android.hardware.media.c2.IComponent.BlockPool createBlockPool(in int allocatorId);
+  android.hardware.media.c2.IComponent.BlockPool createBlockPool(in android.hardware.media.c2.IComponent.BlockPoolAllocator allocator);
   void destroyBlockPool(in long blockPoolId);
   void drain(in boolean withEos);
   android.hardware.media.c2.WorkBundle flush();
@@ -43,11 +43,14 @@
   void queue(in android.hardware.media.c2.WorkBundle workBundle);
   void release();
   void reset();
-  void setDecoderOutputAllocator(in android.hardware.media.c2.IGraphicBufferAllocator allocator);
   void start();
   void stop();
   parcelable BlockPool {
     long blockPoolId;
     android.hardware.media.c2.IConfigurable configurable;
   }
+  union BlockPoolAllocator {
+    int allocatorId;
+    android.hardware.media.c2.IGraphicBufferAllocator igba;
+  }
 }
diff --git a/media/c2/aidl/android/hardware/media/c2/IComponent.aidl b/media/c2/aidl/android/hardware/media/c2/IComponent.aidl
index a9fddbb..a330d46 100644
--- a/media/c2/aidl/android/hardware/media/c2/IComponent.aidl
+++ b/media/c2/aidl/android/hardware/media/c2/IComponent.aidl
@@ -43,6 +43,18 @@
         long blockPoolId;
         IConfigurable configurable;
     }
+
+    /**
+     * Allocator for C2BlockPool.
+     *
+     * C2BlockPool will use a C2Allocator which is specified by an id.
+     * or C2AIDL allocator interface directly.
+     */
+    union BlockPoolAllocator {
+        int allocatorId;
+        IGraphicBufferAllocator igba;
+    }
+
     /**
      * Configures a component for a tunneled playback mode.
      *
@@ -86,7 +98,8 @@
      * destroyBlockPool(), reset() or release(). reset() and release() must
      * destroy all `C2BlockPool` objects that have been created.
      *
-     * @param allocatorId Id of a `C2Allocator`.
+     * @param allocator AIDL allocator interface or C2Allocator specifier
+     *     for C2BlockPool
      * @param out configurable Configuration interface for the created pool. This
      *     must not be null.
      * @return Created block pool information. This could be used to config/query and
@@ -97,7 +110,7 @@
      *   - `Status::TIMED_OUT` - The operation cannot be finished in a timely manner.
      *   - `Status::CORRUPTED` - Some unknown error occurred.
      */
-    BlockPool createBlockPool(in int allocatorId);
+    BlockPool createBlockPool(in BlockPoolAllocator allocator);
 
     /**
      * Destroys a local block pool previously created by createBlockPool().
@@ -232,17 +245,6 @@
     void reset();
 
     /**
-     * Specify an allocator for decoder output buffer from HAL.
-     *
-     * The method will be used once during the life-cycle of a codec instance.
-     * @param allocator Decoder output buffer allocator from the client
-     * @throws ServiceSpecificException with one of the following values
-     *   - `Status::CANNOT_DO` - The component does not support allocating from the client.
-     *   - `Status::CORRUPTED` - Some unknown error occurred.
-     */
-    void setDecoderOutputAllocator(in IGraphicBufferAllocator allocator);
-
-    /**
      * Starts the component.
      *
      * This method must be supported in stopped state as well as tripped state.