diff --git a/Android.bp b/Android.bp
index 0cd985d..afacd1c 100644
--- a/Android.bp
+++ b/Android.bp
@@ -462,7 +462,7 @@
         "telecomm/java/com/android/internal/telecom/RemoteServiceCallback.aidl",
         "telephony/java/android/telephony/data/IDataService.aidl",
         "telephony/java/android/telephony/data/IDataServiceCallback.aidl",
-        "telephony/java/android/telephony/ims/internal/aidl/IImsCallSessionListener.aidl",
+        "telephony/java/android/telephony/ims/aidl/IImsCallSessionListener.aidl",
         "telephony/java/android/telephony/ims/internal/aidl/IImsCapabilityCallback.aidl",
         "telephony/java/android/telephony/ims/internal/aidl/IImsConfig.aidl",
         "telephony/java/android/telephony/ims/internal/aidl/IImsConfigCallback.aidl",
@@ -471,7 +471,8 @@
         "telephony/java/android/telephony/ims/internal/aidl/IImsRcsFeature.aidl",
         "telephony/java/android/telephony/ims/internal/aidl/IImsServiceController.aidl",
         "telephony/java/android/telephony/ims/internal/aidl/IImsServiceControllerListener.aidl",
-	"telephony/java/android/telephony/mbms/IMbmsDownloadSessionCallback.aidl",
+	    "telephony/java/android/telephony/ims/internal/aidl/IImsSmsListener.aidl",
+        "telephony/java/android/telephony/mbms/IMbmsDownloadSessionCallback.aidl",
         "telephony/java/android/telephony/mbms/IMbmsStreamingSessionCallback.aidl",
         "telephony/java/android/telephony/mbms/IDownloadStateCallback.aidl",
         "telephony/java/android/telephony/mbms/IStreamingServiceCallback.aidl",
@@ -495,7 +496,7 @@
         "telephony/java/com/android/ims/internal/IImsService.aidl",
         "telephony/java/com/android/ims/internal/IImsServiceController.aidl",
         "telephony/java/com/android/ims/internal/IImsServiceFeatureCallback.aidl",
-	"telephony/java/com/android/ims/internal/IImsSmsListener.aidl",
+	    "telephony/java/com/android/ims/internal/IImsSmsListener.aidl",
         "telephony/java/com/android/ims/internal/IImsStreamMediaSession.aidl",
         "telephony/java/com/android/ims/internal/IImsUt.aidl",
         "telephony/java/com/android/ims/internal/IImsUtListener.aidl",
diff --git a/telephony/java/android/telephony/ims/internal/ImsCallSessionListener.java b/telephony/java/android/telephony/ims/ImsCallSessionListener.java
similarity index 87%
rename from telephony/java/android/telephony/ims/internal/ImsCallSessionListener.java
rename to telephony/java/android/telephony/ims/ImsCallSessionListener.java
index 5d16dd5..96c7af6 100644
--- a/telephony/java/android/telephony/ims/internal/ImsCallSessionListener.java
+++ b/telephony/java/android/telephony/ims/ImsCallSessionListener.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2017 The Android Open Source Project
+ * Copyright (C) 2018 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.
@@ -14,16 +14,17 @@
  * limitations under the License
  */
 
-package android.telephony.ims.internal;
+package android.telephony.ims;
 
 import android.os.RemoteException;
-import android.telephony.ims.internal.aidl.IImsCallSessionListener;
+import android.telephony.ims.aidl.IImsCallSessionListener;
 
 import com.android.ims.ImsCallProfile;
 import com.android.ims.ImsConferenceState;
 import com.android.ims.ImsReasonInfo;
 import com.android.ims.ImsStreamMediaProfile;
 import com.android.ims.ImsSuppServiceNotification;
+import com.android.ims.internal.IImsCallSession;
 import com.android.ims.internal.ImsCallSession;
 
 /**
@@ -138,6 +139,20 @@
     }
 
     /**
+     * Called when the session merge has been started.  At this point, the {@code newSession}
+     * represents the session which has been initiated to the IMS conference server for the
+     * new merged conference.
+     *
+     * @param newSession the session object that is merged with an active & hold session
+     *
+     * @hide
+     */
+    public void callSessionMergeStarted(IImsCallSession newSession, ImsCallProfile profile)
+            throws RemoteException {
+        mListener.callSessionMergeStarted(newSession, profile);
+    }
+
+    /**
      * Called when the session merge is successful and the merged session is active.
      *
      * @param newSession the new session object that is used for the conference
@@ -147,6 +162,17 @@
     }
 
     /**
+     * Called when the session merge is successful and the merged session is active.
+     *
+     * @param newSession the new session object that is used for the conference
+     *
+     * @hide
+     */
+    public void callSessionMergeComplete(IImsCallSession newSession) throws RemoteException {
+        mListener.callSessionMergeComplete(newSession);
+    }
+
+    /**
      * Called when the session merge has failed.
      *
      * @param reasonInfo detailed reason of the call merge failure
@@ -191,6 +217,18 @@
     }
 
     /**
+     * Called when the session has been extended to a conference session.
+     *
+     * @param newSession the session object that is extended to the conference
+     *      from the active session
+     * @hide
+     */
+    public void callSessionConferenceExtended(IImsCallSession newSession, ImsCallProfile profile)
+            throws RemoteException {
+        mListener.callSessionConferenceExtended(newSession, profile);
+    }
+
+    /**
      * Called when the conference extension has failed.
      *
      * @param reasonInfo detailed reason of the conference extension failure
@@ -209,6 +247,16 @@
     }
 
     /**
+     * Called when the conference extension is received from the remote user.
+     *
+     * @hide
+     */
+    public void callSessionConferenceExtendReceived(IImsCallSession newSession,
+            ImsCallProfile profile) throws RemoteException {
+        mListener.callSessionConferenceExtendReceived(newSession, profile);
+    }
+
+    /**
      * Called when the invitation request of the participants is delivered to the conference
      * server.
      */
diff --git a/telephony/java/android/telephony/ims/internal/aidl/IImsCallSessionListener.aidl b/telephony/java/android/telephony/ims/aidl/IImsCallSessionListener.aidl
similarity index 98%
rename from telephony/java/android/telephony/ims/internal/aidl/IImsCallSessionListener.aidl
rename to telephony/java/android/telephony/ims/aidl/IImsCallSessionListener.aidl
index 2fb6744..e6a18d0 100644
--- a/telephony/java/android/telephony/ims/internal/aidl/IImsCallSessionListener.aidl
+++ b/telephony/java/android/telephony/ims/aidl/IImsCallSessionListener.aidl
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package android.telephony.ims.internal.aidl;
+package android.telephony.ims.aidl;
 
 import com.android.ims.ImsStreamMediaProfile;
 import com.android.ims.ImsCallProfile;
diff --git a/telephony/java/android/telephony/ims/compat/feature/MMTelFeature.java b/telephony/java/android/telephony/ims/compat/feature/MMTelFeature.java
new file mode 100644
index 0000000..403bb60
--- /dev/null
+++ b/telephony/java/android/telephony/ims/compat/feature/MMTelFeature.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2018 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.telephony.ims.compat.feature;
+
+import com.android.ims.ImsCallProfile;
+import com.android.ims.internal.IImsCallSession;
+import com.android.ims.internal.IImsCallSessionListener;
+import com.android.ims.internal.ImsCallSession;
+
+/**
+ * Compatability layer for older implementations of MMTelFeature.
+ *
+ * @hide
+ */
+
+public class MMTelFeature extends android.telephony.ims.feature.MMTelFeature {
+
+    @Override
+    public final IImsCallSession createCallSession(int sessionId, ImsCallProfile profile) {
+        return createCallSession(sessionId, profile, null /*listener*/);
+    }
+
+    /**
+     * Creates an {@link ImsCallSession} with the specified call profile.
+     *
+     * @param sessionId a session id which is obtained from {@link #startSession}
+     * @param profile a call profile to make the call
+     * @param listener An implementation of IImsCallSessionListener.
+     */
+    public IImsCallSession createCallSession(int sessionId, ImsCallProfile profile,
+            IImsCallSessionListener listener) {
+        return null;
+    }
+}
diff --git a/telephony/java/android/telephony/ims/compat/stub/ImsCallSessionImplBase.java b/telephony/java/android/telephony/ims/compat/stub/ImsCallSessionImplBase.java
new file mode 100644
index 0000000..6725d29
--- /dev/null
+++ b/telephony/java/android/telephony/ims/compat/stub/ImsCallSessionImplBase.java
@@ -0,0 +1,276 @@
+/*
+ * Copyright (C) 2018 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.telephony.ims.compat.stub;
+
+import android.os.RemoteException;
+import android.telephony.ims.ImsCallSessionListener;
+
+import com.android.ims.ImsCallProfile;
+import com.android.ims.ImsConferenceState;
+import com.android.ims.ImsReasonInfo;
+import com.android.ims.ImsStreamMediaProfile;
+import com.android.ims.ImsSuppServiceNotification;
+import com.android.ims.internal.IImsCallSession;
+import com.android.ims.internal.IImsCallSessionListener;
+import com.android.ims.internal.ImsCallSession;
+
+/**
+ * Compat implementation of ImsCallSessionImplBase for older implementations.
+ *
+ * DO NOT remove or change the existing APIs, only add new ones to this Base implementation or you
+ * will break other implementations of ImsCallSession maintained by other ImsServices.
+ *
+ * @hide
+ */
+
+public class ImsCallSessionImplBase extends android.telephony.ims.stub.ImsCallSessionImplBase {
+
+    @Override
+    public final void setListener(ImsCallSessionListener listener) {
+        setListener(new ImsCallSessionListenerConverter(listener));
+    }
+
+    /**
+     * Sets the listener to listen to the session events. An {@link ImsCallSession}
+     * can only hold one listener at a time. Subsequent calls to this method
+     * override the previous listener.
+     *
+     * @param listener to listen to the session events of this object
+     */
+    public void setListener(IImsCallSessionListener listener) {
+
+    }
+
+    /**
+     * There are two different ImsCallSessionListeners that need to reconciled here, we need to
+     * convert the "old" version of the com.android.ims.internal.IImsCallSessionListener to the
+     * "new" version of the Listener android.telephony.ims.ImsCallSessionListener when calling
+     * back to the framework.
+     */
+    private class ImsCallSessionListenerConverter extends IImsCallSessionListener.Stub {
+
+        private final ImsCallSessionListener mNewListener;
+
+        public ImsCallSessionListenerConverter(ImsCallSessionListener listener) {
+            mNewListener = listener;
+        }
+
+        @Override
+        public void callSessionProgressing(IImsCallSession i,
+                ImsStreamMediaProfile imsStreamMediaProfile) throws RemoteException {
+            mNewListener.callSessionProgressing(imsStreamMediaProfile);
+        }
+
+        @Override
+        public void callSessionStarted(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionInitiated(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionStartFailed(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionInitiatedFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionTerminated(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionTerminated(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionHeld(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionHeld(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionHoldFailed(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionHoldFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionHoldReceived(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionHoldReceived(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionResumed(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionResumed(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionResumeFailed(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionResumeFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionResumeReceived(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionResumeReceived(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionMergeStarted(IImsCallSession i, IImsCallSession newSession,
+                ImsCallProfile profile)
+                throws RemoteException {
+            mNewListener.callSessionMergeStarted(newSession, profile);
+        }
+
+        @Override
+        public void callSessionMergeComplete(IImsCallSession iImsCallSession)
+                throws RemoteException {
+            mNewListener.callSessionMergeComplete(iImsCallSession);
+        }
+
+        @Override
+        public void callSessionMergeFailed(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionMergeFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionUpdated(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionUpdated(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionUpdateFailed(IImsCallSession i, ImsReasonInfo imsReasonInfo)
+                throws RemoteException {
+            mNewListener.callSessionUpdateFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionUpdateReceived(IImsCallSession i, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionUpdateReceived(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionConferenceExtended(IImsCallSession i, IImsCallSession newSession,
+                ImsCallProfile imsCallProfile) throws RemoteException {
+            mNewListener.callSessionConferenceExtended(newSession, imsCallProfile);
+        }
+
+        @Override
+        public void callSessionConferenceExtendFailed(IImsCallSession i,
+                ImsReasonInfo imsReasonInfo) throws RemoteException {
+            mNewListener.callSessionConferenceExtendFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionConferenceExtendReceived(IImsCallSession i,
+                IImsCallSession newSession, ImsCallProfile imsCallProfile)
+                throws RemoteException {
+            mNewListener.callSessionConferenceExtendReceived(newSession, imsCallProfile);
+        }
+
+        @Override
+        public void callSessionInviteParticipantsRequestDelivered(IImsCallSession i)
+                throws RemoteException {
+            mNewListener.callSessionInviteParticipantsRequestDelivered();
+        }
+
+        @Override
+        public void callSessionInviteParticipantsRequestFailed(IImsCallSession i,
+                ImsReasonInfo imsReasonInfo) throws RemoteException {
+            mNewListener.callSessionInviteParticipantsRequestFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionRemoveParticipantsRequestDelivered(IImsCallSession i)
+                throws RemoteException {
+            mNewListener.callSessionRemoveParticipantsRequestDelivered();
+        }
+
+        @Override
+        public void callSessionRemoveParticipantsRequestFailed(IImsCallSession i,
+                ImsReasonInfo imsReasonInfo) throws RemoteException {
+            mNewListener.callSessionRemoveParticipantsRequestFailed(imsReasonInfo);
+        }
+
+        @Override
+        public void callSessionConferenceStateUpdated(IImsCallSession i,
+                ImsConferenceState imsConferenceState) throws RemoteException {
+            mNewListener.callSessionConferenceStateUpdated(imsConferenceState);
+        }
+
+        @Override
+        public void callSessionUssdMessageReceived(IImsCallSession i, int mode, String message)
+                throws RemoteException {
+            mNewListener.callSessionUssdMessageReceived(mode, message);
+        }
+
+        @Override
+        public void callSessionHandover(IImsCallSession i, int srcAccessTech, int targetAccessTech,
+                ImsReasonInfo reasonInfo) throws RemoteException {
+            mNewListener.callSessionHandover(srcAccessTech, targetAccessTech, reasonInfo);
+        }
+
+        @Override
+        public void callSessionHandoverFailed(IImsCallSession i, int srcAccessTech,
+                int targetAccessTech, ImsReasonInfo reasonInfo) throws RemoteException {
+            mNewListener.callSessionHandoverFailed(srcAccessTech, targetAccessTech, reasonInfo);
+        }
+
+        @Override
+        public void callSessionMayHandover(IImsCallSession i, int srcAccessTech, int targetAccessTech)
+                throws RemoteException {
+            mNewListener.callSessionMayHandover(srcAccessTech, targetAccessTech);
+        }
+
+        @Override
+        public void callSessionTtyModeReceived(IImsCallSession iImsCallSession, int mode)
+                throws RemoteException {
+            mNewListener.callSessionTtyModeReceived(mode);
+        }
+
+        @Override
+        public void callSessionMultipartyStateChanged(IImsCallSession i, boolean isMultiparty)
+                throws RemoteException {
+            mNewListener.callSessionMultipartyStateChanged(isMultiparty);
+        }
+
+        @Override
+        public void callSessionSuppServiceReceived(IImsCallSession i,
+                ImsSuppServiceNotification imsSuppServiceNotification) throws RemoteException {
+            mNewListener.callSessionSuppServiceReceived(imsSuppServiceNotification);
+        }
+
+        @Override
+        public void callSessionRttModifyRequestReceived(IImsCallSession i,
+                ImsCallProfile imsCallProfile) throws RemoteException {
+            mNewListener.callSessionRttModifyRequestReceived(imsCallProfile);
+        }
+
+        @Override
+        public void callSessionRttModifyResponseReceived(int status) throws RemoteException {
+            mNewListener.callSessionRttModifyResponseReceived(status);
+        }
+
+        @Override
+        public void callSessionRttMessageReceived(String rttMessage) throws RemoteException {
+            mNewListener.callSessionRttMessageReceived(rttMessage);
+        }
+    }
+}
diff --git a/telephony/java/android/telephony/ims/feature/MMTelFeature.java b/telephony/java/android/telephony/ims/feature/MMTelFeature.java
index 93c316f..68d63df 100644
--- a/telephony/java/android/telephony/ims/feature/MMTelFeature.java
+++ b/telephony/java/android/telephony/ims/feature/MMTelFeature.java
@@ -23,7 +23,6 @@
 
 import com.android.ims.ImsCallProfile;
 import com.android.ims.internal.IImsCallSession;
-import com.android.ims.internal.IImsCallSessionListener;
 import com.android.ims.internal.IImsConfig;
 import com.android.ims.internal.IImsEcbm;
 import com.android.ims.internal.IImsMMTelFeature;
@@ -110,10 +109,10 @@
         }
 
         @Override
-        public IImsCallSession createCallSession(int sessionId, ImsCallProfile profile,
-                IImsCallSessionListener listener) throws RemoteException {
+        public IImsCallSession createCallSession(int sessionId, ImsCallProfile profile)
+                throws RemoteException {
             synchronized (mLock) {
-                return MMTelFeature.this.createCallSession(sessionId, profile, listener);
+                return MMTelFeature.this.createCallSession(sessionId, profile);
             }
         }
 
@@ -326,10 +325,8 @@
      *
      * @param sessionId a session id which is obtained from {@link #startSession}
      * @param profile a call profile to make the call
-     * @param listener An implementation of IImsCallSessionListener.
      */
-    public IImsCallSession createCallSession(int sessionId, ImsCallProfile profile,
-            IImsCallSessionListener listener) {
+    public IImsCallSession createCallSession(int sessionId, ImsCallProfile profile) {
         return null;
     }
 
diff --git a/telephony/java/android/telephony/ims/internal/aidl/IImsMmTelFeature.aidl b/telephony/java/android/telephony/ims/internal/aidl/IImsMmTelFeature.aidl
index e226ada..18afc6a 100644
--- a/telephony/java/android/telephony/ims/internal/aidl/IImsMmTelFeature.aidl
+++ b/telephony/java/android/telephony/ims/internal/aidl/IImsMmTelFeature.aidl
@@ -19,7 +19,6 @@
 import android.os.Message;
 import android.telephony.ims.internal.aidl.IImsMmTelListener;
 import android.telephony.ims.internal.aidl.IImsCapabilityCallback;
-import android.telephony.ims.internal.aidl.IImsCallSessionListener;
 import android.telephony.ims.internal.feature.CapabilityChangeRequest;
 
 import com.android.ims.ImsCallProfile;
@@ -30,14 +29,14 @@
 import com.android.ims.internal.IImsUt;
 
 /**
- * See SmsImplBase for more information.
+ * See MmTelFeature for more information.
  * {@hide}
  */
 interface IImsMmTelFeature {
     void setListener(IImsMmTelListener l);
     int getFeatureState();
     ImsCallProfile createCallProfile(int callSessionType, int callType);
-    IImsCallSession createCallSession(in ImsCallProfile profile, IImsCallSessionListener listener);
+    IImsCallSession createCallSession(in ImsCallProfile profile);
     IImsUt getUtInterface();
     IImsEcbm getEcbmInterface();
     void setUiTtyMode(int uiTtyMode, in Message onCompleteMessage);
@@ -49,4 +48,11 @@
             IImsCapabilityCallback c);
     oneway void queryCapabilityConfiguration(int capability, int radioTech,
             IImsCapabilityCallback c);
+    // SMS APIs
+    void setSmsListener(IImsSmsListener l);
+    oneway void sendSms(in int token, int messageRef, String format, String smsc, boolean retry,
+            in byte[] pdu);
+    oneway void acknowledgeSms(int token, int messageRef, int result);
+    oneway void acknowledgeSmsReport(int token, int messageRef, int result);
+    String getSmsFormat();
 }
diff --git a/telephony/java/android/telephony/ims/internal/feature/MmTelFeature.java b/telephony/java/android/telephony/ims/internal/feature/MmTelFeature.java
index 9b576c7..23e0302 100644
--- a/telephony/java/android/telephony/ims/internal/feature/MmTelFeature.java
+++ b/telephony/java/android/telephony/ims/internal/feature/MmTelFeature.java
@@ -20,11 +20,10 @@
 import android.os.Message;
 import android.os.RemoteException;
 import android.telecom.TelecomManager;
-import android.telephony.ims.internal.ImsCallSessionListener;
-import android.telephony.ims.internal.aidl.IImsCallSessionListener;
 import android.telephony.ims.internal.aidl.IImsCapabilityCallback;
 import android.telephony.ims.internal.aidl.IImsMmTelFeature;
 import android.telephony.ims.internal.aidl.IImsMmTelListener;
+import android.telephony.ims.internal.stub.SmsImplBase;
 import android.telephony.ims.stub.ImsRegistrationImplBase;
 import android.telephony.ims.stub.ImsEcbmImplBase;
 import android.telephony.ims.stub.ImsMultiEndpointImplBase;
@@ -35,6 +34,7 @@
 import com.android.ims.internal.IImsCallSession;
 import com.android.ims.internal.IImsEcbm;
 import com.android.ims.internal.IImsMultiEndpoint;
+import com.android.ims.internal.IImsSmsListener;
 import com.android.ims.internal.IImsUt;
 import com.android.ims.internal.ImsCallSession;
 import com.android.internal.annotations.VisibleForTesting;
@@ -80,11 +80,9 @@
         }
 
         @Override
-        public IImsCallSession createCallSession(ImsCallProfile profile,
-                IImsCallSessionListener listener) throws RemoteException {
+        public IImsCallSession createCallSession(ImsCallProfile profile) throws RemoteException {
             synchronized (mLock) {
-                ImsCallSession s = MmTelFeature.this.createCallSession(profile,
-                        new ImsCallSessionListener(listener));
+                ImsCallSession s = MmTelFeature.this.createCallSession(profile);
                 return s != null ? s.getSession() : null;
             }
         }
@@ -143,6 +141,40 @@
                 IImsCapabilityCallback c) {
             queryCapabilityConfigurationInternal(capability, radioTech, c);
         }
+
+        @Override
+        public void setSmsListener(IImsSmsListener l) throws RemoteException {
+            MmTelFeature.this.setSmsListener(l);
+        }
+
+        @Override
+        public void sendSms(int token, int messageRef, String format, String smsc, boolean retry,
+                byte[] pdu) {
+            synchronized (mLock) {
+                MmTelFeature.this.sendSms(token, messageRef, format, smsc, retry, pdu);
+            }
+        }
+
+        @Override
+        public void acknowledgeSms(int token, int messageRef, int result) {
+            synchronized (mLock) {
+                MmTelFeature.this.acknowledgeSms(token, messageRef, result);
+            }
+        }
+
+        @Override
+        public void acknowledgeSmsReport(int token, int messageRef, int result) {
+            synchronized (mLock) {
+                MmTelFeature.this.acknowledgeSmsReport(token, messageRef, result);
+            }
+        }
+
+        @Override
+        public String getSmsFormat() {
+            synchronized (mLock) {
+                return MmTelFeature.this.getSmsFormat();
+            }
+        }
     };
 
     /**
@@ -370,10 +402,8 @@
      * {@link ImsCallSession} directly.
      *
      * @param profile a call profile to make the call
-     * @param listener An implementation of IImsCallSessionListener.
      */
-    public ImsCallSession createCallSession(ImsCallProfile profile,
-            ImsCallSessionListener listener) {
+    public ImsCallSession createCallSession(ImsCallProfile profile) {
         // Base Implementation - Should be overridden
         return null;
     }
@@ -415,6 +445,40 @@
         // Base Implementation - Should be overridden
     }
 
+    public void setSmsListener(IImsSmsListener listener) {
+        getSmsImplementation().registerSmsListener(listener);
+    }
+
+    public void sendSms(int token, int messageRef, String format, String smsc, boolean isRetry,
+            byte[] pdu) {
+        getSmsImplementation().sendSms(token, messageRef, format, smsc, isRetry, pdu);
+    }
+
+    public void acknowledgeSms(int token, int messageRef,
+            @SmsImplBase.DeliverStatusResult int result) {
+        getSmsImplementation().acknowledgeSms(token, messageRef, result);
+    }
+
+    public void acknowledgeSmsReport(int token, int messageRef,
+            @SmsImplBase.StatusReportResult int result) {
+        getSmsImplementation().acknowledgeSmsReport(token, messageRef, result);
+    }
+
+    /**
+     * Must be overridden by IMS Provider to be able to support SMS over IMS. Otherwise a default
+     * non-functional implementation is returned.
+     *
+     * @return an instance of {@link SmsImplBase} which should be implemented by the IMS
+     * Provider.
+     */
+    public SmsImplBase getSmsImplementation() {
+        return new SmsImplBase();
+    }
+
+    private String getSmsFormat() {
+        return getSmsImplementation().getSmsFormat();
+    }
+
     /**{@inheritDoc}*/
     @Override
     public void onFeatureRemoved() {
diff --git a/telephony/java/android/telephony/ims/stub/ImsCallSessionImplBase.java b/telephony/java/android/telephony/ims/stub/ImsCallSessionImplBase.java
index 80b2f78..95243fd 100644
--- a/telephony/java/android/telephony/ims/stub/ImsCallSessionImplBase.java
+++ b/telephony/java/android/telephony/ims/stub/ImsCallSessionImplBase.java
@@ -18,12 +18,13 @@
 
 import android.os.Message;
 import android.os.RemoteException;
+import android.telephony.ims.ImsCallSessionListener;
+import android.telephony.ims.aidl.IImsCallSessionListener;
 
 import com.android.ims.ImsCallProfile;
 import com.android.ims.ImsStreamMediaProfile;
 import com.android.ims.internal.ImsCallSession;
 import com.android.ims.internal.IImsCallSession;
-import com.android.ims.internal.IImsCallSessionListener;
 import com.android.ims.internal.IImsVideoCallProvider;
 
 /**
@@ -38,11 +39,26 @@
 
 public class ImsCallSessionImplBase extends IImsCallSession.Stub {
 
+    @Override
+    public final void setListener(IImsCallSessionListener listener) throws RemoteException {
+        setListener(new ImsCallSessionListener(listener));
+    }
+
+    /**
+     * Sets the listener to listen to the session events. An {@link ImsCallSession}
+     * can only hold one listener at a time. Subsequent calls to this method
+     * override the previous listener.
+     *
+     * @param listener to listen to the session events of this object
+     */
+    public void setListener(ImsCallSessionListener listener) {
+    }
+
     /**
      * Closes the object. This object is not usable after being closed.
      */
     @Override
-    public void close() throws RemoteException {
+    public void close() {
 
     }
 
@@ -52,7 +68,7 @@
      * @return the call ID
      */
     @Override
-    public String getCallId() throws RemoteException {
+    public String getCallId() {
         return null;
     }
 
@@ -62,7 +78,7 @@
      * @return the {@link ImsCallProfile} that this session is associated with
      */
     @Override
-    public ImsCallProfile getCallProfile() throws RemoteException {
+    public ImsCallProfile getCallProfile() {
         return null;
     }
 
@@ -72,7 +88,7 @@
      * @return the local {@link ImsCallProfile} that this session is associated with
      */
     @Override
-    public ImsCallProfile getLocalCallProfile() throws RemoteException {
+    public ImsCallProfile getLocalCallProfile() {
         return null;
     }
 
@@ -82,7 +98,7 @@
      * @return the remote {@link ImsCallProfile} that this session is associated with
      */
     @Override
-    public ImsCallProfile getRemoteCallProfile() throws RemoteException {
+    public ImsCallProfile getRemoteCallProfile() {
         return null;
     }
 
@@ -92,7 +108,7 @@
      * @return the string value associated with the specified property
      */
     @Override
-    public String getProperty(String name) throws RemoteException {
+    public String getProperty(String name) {
         return null;
     }
 
@@ -103,7 +119,7 @@
      * @return the session state
      */
     @Override
-    public int getState() throws RemoteException {
+    public int getState() {
         return ImsCallSession.State.INVALID;
     }
 
@@ -113,28 +129,17 @@
      * @return true if the session is in call, false otherwise
      */
     @Override
-    public boolean isInCall() throws RemoteException {
+    public boolean isInCall() {
         return false;
     }
 
     /**
-     * Sets the listener to listen to the session events. An {@link ImsCallSession}
-     * can only hold one listener at a time. Subsequent calls to this method
-     * override the previous listener.
-     *
-     * @param listener to listen to the session events of this object
-     */
-    @Override
-    public void setListener(IImsCallSessionListener listener) throws RemoteException {
-    }
-
-    /**
      * Mutes or unmutes the mic for the active call.
      *
      * @param muted true if the call is muted, false otherwise
      */
     @Override
-    public void setMute(boolean muted) throws RemoteException {
+    public void setMute(boolean muted) {
     }
 
     /**
@@ -150,7 +155,7 @@
      * {@link ImsCallSession.Listener#callSessionStartFailed}
      */
     @Override
-    public void start(String callee, ImsCallProfile profile) throws RemoteException {
+    public void start(String callee, ImsCallProfile profile) {
     }
 
     /**
@@ -166,8 +171,7 @@
      * {@link ImsCallSession.Listener#callSessionStartFailed}
      */
     @Override
-    public void startConference(String[] participants, ImsCallProfile profile)
-            throws RemoteException {
+    public void startConference(String[] participants, ImsCallProfile profile) {
     }
 
     /**
@@ -178,7 +182,7 @@
      * @see {@link ImsCallSession.Listener#callSessionStarted}
      */
     @Override
-    public void accept(int callType, ImsStreamMediaProfile profile) throws RemoteException {
+    public void accept(int callType, ImsStreamMediaProfile profile) {
     }
 
     /**
@@ -189,7 +193,7 @@
      * {@link ImsCallSession.Listener#callSessionStartFailed}
      */
     @Override
-    public void reject(int reason) throws RemoteException {
+    public void reject(int reason) {
     }
 
     /**
@@ -201,7 +205,7 @@
      * @see {@link ImsCallSession.Listener#callSessionTerminated}
      */
     @Override
-    public void terminate(int reason) throws RemoteException {
+    public void terminate(int reason) {
     }
 
     /**
@@ -213,7 +217,7 @@
      * {@link ImsCallSession.Listener#callSessionHoldFailed}
      */
     @Override
-    public void hold(ImsStreamMediaProfile profile) throws RemoteException {
+    public void hold(ImsStreamMediaProfile profile) {
     }
 
     /**
@@ -225,7 +229,7 @@
      * {@link ImsCallSession.Listener#callSessionResumeFailed}
      */
     @Override
-    public void resume(ImsStreamMediaProfile profile) throws RemoteException {
+    public void resume(ImsStreamMediaProfile profile) {
     }
 
     /**
@@ -240,7 +244,7 @@
      *      {@link ImsCallSession.Listener#callSessionMergeFailed}
      */
     @Override
-    public void merge() throws RemoteException {
+    public void merge() {
     }
 
     /**
@@ -252,7 +256,7 @@
      * {@link ImsCallSession.Listener#callSessionUpdateFailed}
      */
     @Override
-    public void update(int callType, ImsStreamMediaProfile profile) throws RemoteException {
+    public void update(int callType, ImsStreamMediaProfile profile) {
     }
 
     /**
@@ -264,7 +268,7 @@
      * {@link ImsCallSession.Listener#callSessionConferenceExtendFailed}
      */
     @Override
-    public void extendToConference(String[] participants) throws RemoteException {
+    public void extendToConference(String[] participants) {
     }
 
     /**
@@ -286,7 +290,7 @@
      *      {@link ImsCallSession.Listener#callSessionRemoveParticipantsRequestFailed}
      */
     @Override
-    public void removeParticipants(String[] participants) throws RemoteException {
+    public void removeParticipants(String[] participants) {
     }
 
     /**
@@ -297,7 +301,7 @@
      * @param c the DTMF to send. '0' ~ '9', 'A' ~ 'D', '*', '#' are valid inputs.
      */
     @Override
-    public void sendDtmf(char c, Message result) throws RemoteException {
+    public void sendDtmf(char c, Message result) {
     }
 
     /**
@@ -308,14 +312,14 @@
      * @param c the DTMF to send. '0' ~ '9', 'A' ~ 'D', '*', '#' are valid inputs.
      */
     @Override
-    public void startDtmf(char c) throws RemoteException {
+    public void startDtmf(char c) {
     }
 
     /**
      * Stop a DTMF code.
      */
     @Override
-    public void stopDtmf() throws RemoteException {
+    public void stopDtmf() {
     }
 
     /**
@@ -324,7 +328,7 @@
      * @param ussdMessage USSD message to send
      */
     @Override
-    public void sendUssd(String ussdMessage) throws RemoteException {
+    public void sendUssd(String ussdMessage) {
     }
 
     /**
@@ -333,7 +337,7 @@
      * intermediates between the propriety implementation and Telecomm/InCall.
      */
     @Override
-    public IImsVideoCallProvider getVideoCallProvider() throws RemoteException {
+    public IImsVideoCallProvider getVideoCallProvider() {
         return null;
     }
 
@@ -342,7 +346,7 @@
      * @return {@code True} if the session is multiparty.
      */
     @Override
-    public boolean isMultiparty() throws RemoteException {
+    public boolean isMultiparty() {
         return false;
     }
 
diff --git a/telephony/java/android/telephony/ims/stub/ImsCallSessionListenerImplBase.java b/telephony/java/android/telephony/ims/stub/ImsCallSessionListenerImplBase.java
deleted file mode 100644
index 6c18935..0000000
--- a/telephony/java/android/telephony/ims/stub/ImsCallSessionListenerImplBase.java
+++ /dev/null
@@ -1,298 +0,0 @@
-/*
- * Copyright (C) 2017 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.telephony.ims.stub;
-
-import com.android.ims.ImsCallProfile;
-import com.android.ims.ImsConferenceState;
-import com.android.ims.ImsReasonInfo;
-import com.android.ims.ImsStreamMediaProfile;
-import com.android.ims.ImsSuppServiceNotification;
-import com.android.ims.internal.IImsCallSession;
-import com.android.ims.internal.IImsCallSessionListener;
-
-/**
- * Base implementation of ImsCallSessionListenerBase, which implements stub versions of the methods
- * in the IImsCallSessionListener AIDL. Override the methods that your implementation of
- * ImsCallSessionListener supports.
- *
- * DO NOT remove or change the existing APIs, only add new ones to this Base implementation or you
- * will break other implementations of ImsCallSessionListener maintained by other ImsServices.
- *
- * @hide
- */
-public class ImsCallSessionListenerImplBase extends IImsCallSessionListener.Stub {
-    /**
-     * Notifies the result of the basic session operation (setup / terminate).
-     */
-    @Override
-    public void callSessionProgressing(IImsCallSession session, ImsStreamMediaProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionStarted(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionStartFailed(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionTerminated(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    /**
-     * Notifies the result of the call hold/resume operation.
-     */
-    @Override
-    public void callSessionHeld(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionHoldFailed(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionHoldReceived(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionResumed(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionResumeFailed(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionResumeReceived(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    /**
-     * Notifies the result of call merge operation.
-     */
-    @Override
-    public void callSessionMergeStarted(IImsCallSession session, IImsCallSession newSession,
-            ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionMergeComplete(IImsCallSession session) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionMergeFailed(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    /**
-     * Notifies the result of call upgrade / downgrade or any other call
-     * updates.
-     */
-    @Override
-    public void callSessionUpdated(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionUpdateFailed(IImsCallSession session, ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionUpdateReceived(IImsCallSession session, ImsCallProfile profile) {
-        // no-op
-    }
-
-    /**
-     * Notifies the result of conference extension.
-     */
-    @Override
-    public void callSessionConferenceExtended(IImsCallSession session, IImsCallSession newSession,
-            ImsCallProfile profile) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionConferenceExtendFailed(IImsCallSession session,
-            ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionConferenceExtendReceived(IImsCallSession session,
-            IImsCallSession newSession,
-            ImsCallProfile profile) {
-        // no-op
-    }
-
-    /**
-     * Notifies the result of the participant invitation / removal to/from the
-     * conference session.
-     */
-    @Override
-    public void callSessionInviteParticipantsRequestDelivered(IImsCallSession session) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionInviteParticipantsRequestFailed(IImsCallSession session,
-            ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionRemoveParticipantsRequestDelivered(IImsCallSession session) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionRemoveParticipantsRequestFailed(IImsCallSession session,
-            ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    /**
-     * Notifies the changes of the conference info. the conference session.
-     */
-    @Override
-    public void callSessionConferenceStateUpdated(IImsCallSession session,
-            ImsConferenceState state) {
-        // no-op
-    }
-
-    /**
-     * Notifies the incoming USSD message.
-     */
-    @Override
-    public void callSessionUssdMessageReceived(IImsCallSession session, int mode,
-            String ussdMessage) {
-        // no-op
-    }
-
-    /**
-     * Notifies of a case where a {@link com.android.ims.internal.ImsCallSession} may potentially
-     * handover from one radio technology to another.
-     * @param session
-     * @param srcAccessTech The source radio access technology; one of the access technology
-     *                      constants defined in {@link android.telephony.ServiceState}.  For
-     *                      example {@link android.telephony.ServiceState#RIL_RADIO_TECHNOLOGY_LTE}.
-     * @param targetAccessTech The target radio access technology; one of the access technology
-     *                      constants defined in {@link android.telephony.ServiceState}.  For
-     *                      example {@link android.telephony.ServiceState#RIL_RADIO_TECHNOLOGY_LTE}.
-     */
-    @Override
-    public void callSessionMayHandover(IImsCallSession session, int srcAccessTech,
-            int targetAccessTech) {
-        // no-op
-    }
-
-    /**
-     * Notifies of handover information for this call
-     */
-    @Override
-    public void callSessionHandover(IImsCallSession session, int srcAccessTech,
-            int targetAccessTech,
-            ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    @Override
-    public void callSessionHandoverFailed(IImsCallSession session, int srcAccessTech,
-            int targetAccessTech,
-            ImsReasonInfo reasonInfo) {
-        // no-op
-    }
-
-    /**
-     * Notifies the TTY mode change by remote party.
-     *
-     * @param mode one of the following: -
-     *            {@link com.android.internal.telephony.Phone#TTY_MODE_OFF} -
-     *            {@link com.android.internal.telephony.Phone#TTY_MODE_FULL} -
-     *            {@link com.android.internal.telephony.Phone#TTY_MODE_HCO} -
-     *            {@link com.android.internal.telephony.Phone#TTY_MODE_VCO}
-     */
-    @Override
-    public void callSessionTtyModeReceived(IImsCallSession session, int mode) {
-        // no-op
-    }
-
-    /**
-     * Notifies of a change to the multiparty state for this
-     * {@code ImsCallSession}.
-     *
-     * @param session The call session.
-     * @param isMultiParty {@code true} if the session became multiparty,
-     *            {@code false} otherwise.
-     */
-    @Override
-    public void callSessionMultipartyStateChanged(IImsCallSession session, boolean isMultiParty) {
-        // no-op
-    }
-
-    /**
-     * Notifies the supplementary service information for the current session.
-     */
-    @Override
-    public void callSessionSuppServiceReceived(IImsCallSession session,
-            ImsSuppServiceNotification suppSrvNotification) {
-        // no-op
-    }
-
-    /**
-     * Received RTT modify request from Remote Party
-     * @param session The call session.
-     * @param callProfile ImsCallProfile with updated attribute
-     */
-    @Override
-    public void callSessionRttModifyRequestReceived(IImsCallSession session,
-            ImsCallProfile callProfile) {
-        // no-op
-    }
-
-    /**
-     * Received response for RTT modify request
-     * @param status true : Accepted the request
-     *               false : Declined the request
-     */
-    @Override
-    public void callSessionRttModifyResponseReceived(int status) {
-        // no -op
-    }
-
-    /**
-     * Device received RTT message from Remote UE
-     * @param rttMessage RTT message received
-     */
-    @Override
-    public void callSessionRttMessageReceived(String rttMessage) {
-        // no-op
-    }
-}
-
diff --git a/telephony/java/com/android/ims/internal/IImsCallSession.aidl b/telephony/java/com/android/ims/internal/IImsCallSession.aidl
index c6fc5e5..b477dea 100644
--- a/telephony/java/com/android/ims/internal/IImsCallSession.aidl
+++ b/telephony/java/com/android/ims/internal/IImsCallSession.aidl
@@ -17,9 +17,10 @@
 package com.android.ims.internal;
 
 import android.os.Message;
+import android.telephony.ims.aidl.IImsCallSessionListener;
+
 import com.android.ims.ImsCallProfile;
 import com.android.ims.ImsStreamMediaProfile;
-import com.android.ims.internal.IImsCallSessionListener;
 import com.android.ims.internal.IImsVideoCallProvider;
 
 /**
diff --git a/telephony/java/com/android/ims/internal/IImsMMTelFeature.aidl b/telephony/java/com/android/ims/internal/IImsMMTelFeature.aidl
index 10c7f3e..290a682 100644
--- a/telephony/java/com/android/ims/internal/IImsMMTelFeature.aidl
+++ b/telephony/java/com/android/ims/internal/IImsMMTelFeature.aidl
@@ -20,7 +20,6 @@
 
 import com.android.ims.ImsCallProfile;
 import com.android.ims.internal.IImsCallSession;
-import com.android.ims.internal.IImsCallSessionListener;
 import com.android.ims.internal.IImsConfig;
 import com.android.ims.internal.IImsEcbm;
 import com.android.ims.internal.IImsMultiEndpoint;
@@ -44,8 +43,7 @@
     void addRegistrationListener(in IImsRegistrationListener listener);
     void removeRegistrationListener(in IImsRegistrationListener listener);
     ImsCallProfile createCallProfile(int sessionId, int callSessionType, int callType);
-    IImsCallSession createCallSession(int sessionId, in ImsCallProfile profile,
-            IImsCallSessionListener listener);
+    IImsCallSession createCallSession(int sessionId, in ImsCallProfile profile);
     IImsCallSession getPendingCallSession(int sessionId, String callId);
     IImsUt getUtInterface();
     IImsConfig getConfigInterface();
diff --git a/telephony/java/com/android/ims/internal/ImsCallSession.java b/telephony/java/com/android/ims/internal/ImsCallSession.java
index 1736b80..e914f48 100644
--- a/telephony/java/com/android/ims/internal/ImsCallSession.java
+++ b/telephony/java/com/android/ims/internal/ImsCallSession.java
@@ -18,10 +18,10 @@
 
 import android.os.Message;
 import android.os.RemoteException;
+import android.telephony.ims.aidl.IImsCallSessionListener;
 
 import java.util.Objects;
 
-import android.telephony.ims.stub.ImsCallSessionListenerImplBase;
 import android.util.Log;
 import com.android.ims.ImsCallProfile;
 import com.android.ims.ImsConferenceState;
@@ -987,7 +987,6 @@
      * Sends Rtt Message
      *
      * @param rttMessage rtt text to be sent
-     * @throws ImsException if call is absent
      */
     public void sendRttMessage(String rttMessage) {
         if (mClosed) {
@@ -1004,7 +1003,6 @@
      * Sends RTT Upgrade request
      *
      * @param to   : expected profile
-     * @throws CallStateException
      */
     public void sendRttModifyRequest(ImsCallProfile to) {
         if (mClosed) {
@@ -1021,7 +1019,6 @@
      * Sends RTT Upgrade response
      *
      * @param response : response for upgrade
-     * @throws CallStateException
      */
     public void sendRttModifyResponse(boolean response) {
         if (mClosed) {
@@ -1040,37 +1037,33 @@
      * the application is notified by having one of the methods called on
      * the {@link IImsCallSessionListener}.
      */
-    private class IImsCallSessionListenerProxy extends ImsCallSessionListenerImplBase {
+    private class IImsCallSessionListenerProxy extends IImsCallSessionListener.Stub {
         /**
          * Notifies the result of the basic session operation (setup / terminate).
          */
         @Override
-        public void callSessionProgressing(IImsCallSession session,
-                ImsStreamMediaProfile profile) {
+        public void callSessionProgressing(ImsStreamMediaProfile profile) {
             if (mListener != null) {
                 mListener.callSessionProgressing(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionStarted(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionInitiated(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionStarted(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionStartFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionInitiatedFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionStartFailed(ImsCallSession.this, reasonInfo);
             }
         }
 
         @Override
-        public void callSessionTerminated(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionTerminated(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionTerminated(ImsCallSession.this, reasonInfo);
             }
@@ -1080,48 +1073,42 @@
          * Notifies the result of the call hold/resume operation.
          */
         @Override
-        public void callSessionHeld(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionHeld(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionHeld(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionHoldFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionHoldFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionHoldFailed(ImsCallSession.this, reasonInfo);
             }
         }
 
         @Override
-        public void callSessionHoldReceived(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionHoldReceived(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionHoldReceived(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionResumed(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionResumed(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionResumed(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionResumeFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionResumeFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionResumeFailed(ImsCallSession.this, reasonInfo);
             }
         }
 
         @Override
-        public void callSessionResumeReceived(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionResumeReceived(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionResumeReceived(ImsCallSession.this, profile);
             }
@@ -1130,13 +1117,11 @@
         /**
          * Notifies the start of a call merge operation.
          *
-         * @param session The call session.
          * @param newSession The merged call session.
          * @param profile The call profile.
          */
         @Override
-        public void callSessionMergeStarted(IImsCallSession session,
-                IImsCallSession newSession, ImsCallProfile profile) {
+        public void callSessionMergeStarted(IImsCallSession newSession, ImsCallProfile profile) {
             // This callback can be used for future use to add additional
             // functionality that may be needed between conference start and complete
             Log.d(TAG, "callSessionMergeStarted");
@@ -1173,12 +1158,10 @@
         /**
          * Notifies of a failure to perform a call merge operation.
          *
-         * @param session The call session.
          * @param reasonInfo The merge failure reason.
          */
         @Override
-        public void callSessionMergeFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionMergeFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionMergeFailed(ImsCallSession.this, reasonInfo);
             }
@@ -1188,24 +1171,21 @@
          * Notifies the result of call upgrade / downgrade or any other call updates.
          */
         @Override
-        public void callSessionUpdated(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionUpdated(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionUpdated(ImsCallSession.this, profile);
             }
         }
 
         @Override
-        public void callSessionUpdateFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionUpdateFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionUpdateFailed(ImsCallSession.this, reasonInfo);
             }
         }
 
         @Override
-        public void callSessionUpdateReceived(IImsCallSession session,
-                ImsCallProfile profile) {
+        public void callSessionUpdateReceived(ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionUpdateReceived(ImsCallSession.this, profile);
             }
@@ -1215,8 +1195,8 @@
          * Notifies the result of conference extension.
          */
         @Override
-        public void callSessionConferenceExtended(IImsCallSession session,
-                IImsCallSession newSession, ImsCallProfile profile) {
+        public void callSessionConferenceExtended(IImsCallSession newSession,
+                ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionConferenceExtended(ImsCallSession.this,
                         new ImsCallSession(newSession), profile);
@@ -1224,16 +1204,15 @@
         }
 
         @Override
-        public void callSessionConferenceExtendFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionConferenceExtendFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionConferenceExtendFailed(ImsCallSession.this, reasonInfo);
             }
         }
 
         @Override
-        public void callSessionConferenceExtendReceived(IImsCallSession session,
-                IImsCallSession newSession, ImsCallProfile profile) {
+        public void callSessionConferenceExtendReceived(IImsCallSession newSession,
+                ImsCallProfile profile) {
             if (mListener != null) {
                 mListener.callSessionConferenceExtendReceived(ImsCallSession.this,
                         new ImsCallSession(newSession), profile);
@@ -1245,15 +1224,14 @@
          * the conference session.
          */
         @Override
-        public void callSessionInviteParticipantsRequestDelivered(IImsCallSession session) {
+        public void callSessionInviteParticipantsRequestDelivered() {
             if (mListener != null) {
                 mListener.callSessionInviteParticipantsRequestDelivered(ImsCallSession.this);
             }
         }
 
         @Override
-        public void callSessionInviteParticipantsRequestFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionInviteParticipantsRequestFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionInviteParticipantsRequestFailed(ImsCallSession.this,
                         reasonInfo);
@@ -1261,15 +1239,14 @@
         }
 
         @Override
-        public void callSessionRemoveParticipantsRequestDelivered(IImsCallSession session) {
+        public void callSessionRemoveParticipantsRequestDelivered() {
             if (mListener != null) {
                 mListener.callSessionRemoveParticipantsRequestDelivered(ImsCallSession.this);
             }
         }
 
         @Override
-        public void callSessionRemoveParticipantsRequestFailed(IImsCallSession session,
-                ImsReasonInfo reasonInfo) {
+        public void callSessionRemoveParticipantsRequestFailed(ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionRemoveParticipantsRequestFailed(ImsCallSession.this,
                         reasonInfo);
@@ -1280,8 +1257,7 @@
          * Notifies the changes of the conference info. in the conference session.
          */
         @Override
-        public void callSessionConferenceStateUpdated(IImsCallSession session,
-                ImsConferenceState state) {
+        public void callSessionConferenceStateUpdated(ImsConferenceState state) {
             if (mListener != null) {
                 mListener.callSessionConferenceStateUpdated(ImsCallSession.this, state);
             }
@@ -1291,8 +1267,7 @@
          * Notifies the incoming USSD message.
          */
         @Override
-        public void callSessionUssdMessageReceived(IImsCallSession session,
-                int mode, String ussdMessage) {
+        public void callSessionUssdMessageReceived(int mode, String ussdMessage) {
             if (mListener != null) {
                 mListener.callSessionUssdMessageReceived(ImsCallSession.this, mode, ussdMessage);
             }
@@ -1301,7 +1276,6 @@
         /**
          * Notifies of a case where a {@link com.android.ims.internal.ImsCallSession} may
          * potentially handover from one radio technology to another.
-         * @param session
          * @param srcAccessTech The source radio access technology; one of the access technology
          *                      constants defined in {@link android.telephony.ServiceState}.  For
          *                      example
@@ -1312,8 +1286,7 @@
          *                      {@link android.telephony.ServiceState#RIL_RADIO_TECHNOLOGY_LTE}.
          */
         @Override
-        public void callSessionMayHandover(IImsCallSession session,
-                int srcAccessTech, int targetAccessTech) {
+        public void callSessionMayHandover(int srcAccessTech, int targetAccessTech) {
             if (mListener != null) {
                 mListener.callSessionMayHandover(ImsCallSession.this, srcAccessTech,
                         targetAccessTech);
@@ -1324,9 +1297,8 @@
          * Notifies of handover information for this call
          */
         @Override
-        public void callSessionHandover(IImsCallSession session,
-                                 int srcAccessTech, int targetAccessTech,
-                                 ImsReasonInfo reasonInfo) {
+        public void callSessionHandover(int srcAccessTech, int targetAccessTech,
+                ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionHandover(ImsCallSession.this, srcAccessTech,
                         targetAccessTech, reasonInfo);
@@ -1337,9 +1309,8 @@
          * Notifies of handover failure info for this call
          */
         @Override
-        public void callSessionHandoverFailed(IImsCallSession session,
-                                       int srcAccessTech, int targetAccessTech,
-                                       ImsReasonInfo reasonInfo) {
+        public void callSessionHandoverFailed(int srcAccessTech, int targetAccessTech,
+                ImsReasonInfo reasonInfo) {
             if (mListener != null) {
                 mListener.callSessionHandoverFailed(ImsCallSession.this, srcAccessTech,
                         targetAccessTech, reasonInfo);
@@ -1350,8 +1321,7 @@
          * Notifies the TTY mode received from remote party.
          */
         @Override
-        public void callSessionTtyModeReceived(IImsCallSession session,
-                int mode) {
+        public void callSessionTtyModeReceived(int mode) {
             if (mListener != null) {
                 mListener.callSessionTtyModeReceived(ImsCallSession.this, mode);
             }
@@ -1360,21 +1330,17 @@
         /**
          * Notifies of a change to the multiparty state for this {@code ImsCallSession}.
          *
-         * @param session The call session.
          * @param isMultiParty {@code true} if the session became multiparty, {@code false}
          *      otherwise.
          */
-        public void callSessionMultipartyStateChanged(IImsCallSession session,
-                boolean isMultiParty) {
-
+        public void callSessionMultipartyStateChanged(boolean isMultiParty) {
             if (mListener != null) {
                 mListener.callSessionMultipartyStateChanged(ImsCallSession.this, isMultiParty);
             }
         }
 
         @Override
-        public void callSessionSuppServiceReceived(IImsCallSession session,
-                ImsSuppServiceNotification suppServiceInfo ) {
+        public void callSessionSuppServiceReceived(ImsSuppServiceNotification suppServiceInfo ) {
             if (mListener != null) {
                 mListener.callSessionSuppServiceReceived(ImsCallSession.this, suppServiceInfo);
             }
@@ -1384,8 +1350,7 @@
          * Received RTT modify request from remote party
          */
         @Override
-        public void callSessionRttModifyRequestReceived(IImsCallSession session,
-                ImsCallProfile callProfile) {
+        public void callSessionRttModifyRequestReceived(ImsCallProfile callProfile) {
             if (mListener != null) {
                 mListener.callSessionRttModifyRequestReceived(ImsCallSession.this, callProfile);
             }