diff --git a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/CommonProps.aidl b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/CommonProps.aidl
index 8dbc149..30959b1 100644
--- a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/CommonProps.aidl
+++ b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/CommonProps.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright (C) 2020 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.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
@@ -19,7 +34,7 @@
 @VintfStability
 parcelable CommonProps {
   int sensorId;
-  android.hardware.biometrics.common.SensorStrength sensorStrength;
+  android.hardware.biometrics.common.SensorStrength sensorStrength = android.hardware.biometrics.common.SensorStrength.CONVENIENCE;
   int maxEnrollmentsPerUser;
   android.hardware.biometrics.common.HardwareInfo[] hardwareInfo;
 }
diff --git a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/HardwareInfo.aidl b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/HardwareInfo.aidl
index b94b6b0..8fea864 100644
--- a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/HardwareInfo.aidl
+++ b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/HardwareInfo.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright (C) 2020 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.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/ICancellationSignal.aidl b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/ICancellationSignal.aidl
index 1a875bf..b85a590 100644
--- a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/ICancellationSignal.aidl
+++ b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/ICancellationSignal.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright (C) 2020 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.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/SensorStrength.aidl b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/SensorStrength.aidl
index eaff85d..3b20c9a 100644
--- a/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/SensorStrength.aidl
+++ b/biometrics/common/aidl/aidl_api/android.hardware.biometrics.common/current/android/hardware/biometrics/common/SensorStrength.aidl
@@ -1,14 +1,29 @@
-///////////////////////////////////////////////////////////////////////////////
+/*
+ * Copyright (C) 2020 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.
+ *////////////////////////////////////////////////////////////////////////////////
 // THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
 ///////////////////////////////////////////////////////////////////////////////
 
-// This file is a snapshot of an AIDL interface (or parcelable). Do not try to
-// edit this file. It looks like you are doing that because you have modified
-// an AIDL interface in a backward-incompatible way, e.g., deleting a function
-// from an interface or a field from a parcelable and it broke the build. That
-// breakage is intended.
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
 //
-// You must not make a backward incompatible changes to the AIDL files built
+// You must not make a backward incompatible change to any AIDL file built
 // with the aidl_interface module type with versions property set. The module
 // type is used to build AIDL files in a way that they can be used across
 // independently updatable components of the system. If a device is shipped
diff --git a/biometrics/common/aidl/android/hardware/biometrics/common/CommonProps.aidl b/biometrics/common/aidl/android/hardware/biometrics/common/CommonProps.aidl
index 9c3fd58..59f398e 100644
--- a/biometrics/common/aidl/android/hardware/biometrics/common/CommonProps.aidl
+++ b/biometrics/common/aidl/android/hardware/biometrics/common/CommonProps.aidl
@@ -33,7 +33,7 @@
      * A statically configured strength for this sensor. See the SensorStrength interface for more
      * information.
      */
-    SensorStrength sensorStrength;
+    SensorStrength sensorStrength = SensorStrength.CONVENIENCE;
 
     /**
      * The maximum number of enrollments that a single user can have. Statically configured.
@@ -44,4 +44,4 @@
      * A list of hardware information for subsystems that pertain to this biometric sensor.
      */
     HardwareInfo[] hardwareInfo;
-}
\ No newline at end of file
+}
diff --git a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/BaseFrame.aidl b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/BaseFrame.aidl
index a935101..9939705 100644
--- a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/BaseFrame.aidl
+++ b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/BaseFrame.aidl
@@ -33,7 +33,7 @@
 package android.hardware.biometrics.face;
 @VintfStability
 parcelable BaseFrame {
-  android.hardware.biometrics.face.AcquiredInfo acquiredInfo;
+  android.hardware.biometrics.face.AcquiredInfo acquiredInfo = android.hardware.biometrics.face.AcquiredInfo.INSUFFICIENT;
   int vendorCode;
   float pan;
   float tilt;
diff --git a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentFrame.aidl b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentFrame.aidl
index cc78e6b..cb9a6c6 100644
--- a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentFrame.aidl
+++ b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentFrame.aidl
@@ -34,6 +34,6 @@
 @VintfStability
 parcelable EnrollmentFrame {
   @nullable android.hardware.biometrics.face.Cell cell;
-  android.hardware.biometrics.face.EnrollmentStage stage;
+  android.hardware.biometrics.face.EnrollmentStage stage = android.hardware.biometrics.face.EnrollmentStage.FIRST_FRAME_RECEIVED;
   android.hardware.biometrics.face.BaseFrame data;
 }
diff --git a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentStageConfig.aidl b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
index d13eccd..f55aafd 100644
--- a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
+++ b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
@@ -33,6 +33,6 @@
 package android.hardware.biometrics.face;
 @VintfStability
 parcelable EnrollmentStageConfig {
-  android.hardware.biometrics.face.EnrollmentStage stage;
+  android.hardware.biometrics.face.EnrollmentStage stage = android.hardware.biometrics.face.EnrollmentStage.FIRST_FRAME_RECEIVED;
   List<android.hardware.biometrics.face.Cell> cells;
 }
diff --git a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/SensorProps.aidl b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/SensorProps.aidl
index 23a8d4d..69355fb 100644
--- a/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/SensorProps.aidl
+++ b/biometrics/face/aidl/aidl_api/android.hardware.biometrics.face/current/android/hardware/biometrics/face/SensorProps.aidl
@@ -34,7 +34,7 @@
 @VintfStability
 parcelable SensorProps {
   android.hardware.biometrics.common.CommonProps commonProps;
-  android.hardware.biometrics.face.FaceSensorType sensorType;
+  android.hardware.biometrics.face.FaceSensorType sensorType = android.hardware.biometrics.face.FaceSensorType.RGB;
   boolean halControlsPreview;
   int enrollPreviewWidth;
   int enrollPreviewHeight;
diff --git a/biometrics/face/aidl/android/hardware/biometrics/face/BaseFrame.aidl b/biometrics/face/aidl/android/hardware/biometrics/face/BaseFrame.aidl
index 9e6b98a..85535f9 100644
--- a/biometrics/face/aidl/android/hardware/biometrics/face/BaseFrame.aidl
+++ b/biometrics/face/aidl/android/hardware/biometrics/face/BaseFrame.aidl
@@ -29,7 +29,7 @@
      * Information about the frame that can be used by the framework to provide feedback to the
      * user, for example ask the user to move their face in a certain way.
      */
-    AcquiredInfo acquiredInfo;
+    AcquiredInfo acquiredInfo = AcquiredInfo.INSUFFICIENT;
 
     /**
      * If acquiredInfo is set to AcquiredInfo::VENDOR. This is the index into the configuration
diff --git a/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentFrame.aidl b/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentFrame.aidl
index d4f9771..ea0a502 100644
--- a/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentFrame.aidl
+++ b/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentFrame.aidl
@@ -16,9 +16,9 @@
 
 package android.hardware.biometrics.face;
 
+import android.hardware.biometrics.face.BaseFrame;
 import android.hardware.biometrics.face.Cell;
 import android.hardware.biometrics.face.EnrollmentStage;
-import android.hardware.biometrics.face.BaseFrame;
 
 /**
  * Describes an individual frame captured during enrollment.
@@ -33,7 +33,7 @@
     /**
      * The enrollment stage for which this frame was captured.
      */
-    EnrollmentStage stage;
+    EnrollmentStage stage = EnrollmentStage.FIRST_FRAME_RECEIVED;
 
     /**
      * The frame metadata. Can be used by the framework to provide user feedback.
diff --git a/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentStageConfig.aidl b/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
index 0b64e2b..3c31fcc 100644
--- a/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
+++ b/biometrics/face/aidl/android/hardware/biometrics/face/EnrollmentStageConfig.aidl
@@ -24,7 +24,7 @@
     /**
      * The stage that's being configured.
      */
-    EnrollmentStage stage;
+    EnrollmentStage stage = EnrollmentStage.FIRST_FRAME_RECEIVED;
 
     /**
      * Optional list of cells that must be completed to finish this stage.
diff --git a/biometrics/face/aidl/android/hardware/biometrics/face/SensorProps.aidl b/biometrics/face/aidl/android/hardware/biometrics/face/SensorProps.aidl
index 091e322..b11b436 100644
--- a/biometrics/face/aidl/android/hardware/biometrics/face/SensorProps.aidl
+++ b/biometrics/face/aidl/android/hardware/biometrics/face/SensorProps.aidl
@@ -29,7 +29,7 @@
     /**
      * A statically configured sensor type representing this face sensor.
      */
-    FaceSensorType sensorType;
+    FaceSensorType sensorType = FaceSensorType.RGB;
 
     /**
      * Whether or not the HAL is responsible for showing the face enrollment preview to the user.
@@ -76,4 +76,3 @@
      */
     boolean supportsDetectInteraction;
 }
-
diff --git a/biometrics/fingerprint/aidl/aidl_api/android.hardware.biometrics.fingerprint/current/android/hardware/biometrics/fingerprint/SensorProps.aidl b/biometrics/fingerprint/aidl/aidl_api/android.hardware.biometrics.fingerprint/current/android/hardware/biometrics/fingerprint/SensorProps.aidl
index 53ac6dd..00cbb6d 100644
--- a/biometrics/fingerprint/aidl/aidl_api/android.hardware.biometrics.fingerprint/current/android/hardware/biometrics/fingerprint/SensorProps.aidl
+++ b/biometrics/fingerprint/aidl/aidl_api/android.hardware.biometrics.fingerprint/current/android/hardware/biometrics/fingerprint/SensorProps.aidl
@@ -34,7 +34,7 @@
 @VintfStability
 parcelable SensorProps {
   android.hardware.biometrics.common.CommonProps commonProps;
-  android.hardware.biometrics.fingerprint.FingerprintSensorType sensorType;
+  android.hardware.biometrics.fingerprint.FingerprintSensorType sensorType = android.hardware.biometrics.fingerprint.FingerprintSensorType.UNKNOWN;
   android.hardware.biometrics.fingerprint.SensorLocation[] sensorLocations;
   boolean supportsNavigationGestures;
   boolean supportsDetectInteraction;
diff --git a/biometrics/fingerprint/aidl/android/hardware/biometrics/fingerprint/SensorProps.aidl b/biometrics/fingerprint/aidl/android/hardware/biometrics/fingerprint/SensorProps.aidl
index 5222f3e..fd2cf47 100644
--- a/biometrics/fingerprint/aidl/android/hardware/biometrics/fingerprint/SensorProps.aidl
+++ b/biometrics/fingerprint/aidl/android/hardware/biometrics/fingerprint/SensorProps.aidl
@@ -30,7 +30,7 @@
     /**
      * A statically configured sensor type representing this fingerprint sensor.
      */
-    FingerprintSensorType sensorType;
+    FingerprintSensorType sensorType = FingerprintSensorType.UNKNOWN;
 
     /**
      * A list of display-specific locations from where the sensor is usable from. See SensorLocation
@@ -49,4 +49,3 @@
      */
     boolean supportsDetectInteraction;
 }
-