diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/MobileSignalController.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/MobileSignalController.java
index 13e9b16..ed1dca3 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/MobileSignalController.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/MobileSignalController.java
@@ -51,7 +51,7 @@
     @VisibleForTesting
     final PhoneStateListener mPhoneStateListener;
     // Save entire info for logging, we only use the id.
-    private final SubscriptionInfo mSubscriptionInfo;
+    final SubscriptionInfo mSubscriptionInfo;
 
     // @VisibleForDemoMode
     final SparseArray<MobileIconGroup> mNetworkToIconLookup;
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/NetworkControllerImpl.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/NetworkControllerImpl.java
index 57dfff5..2996808 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/NetworkControllerImpl.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/NetworkControllerImpl.java
@@ -66,6 +66,11 @@
     // additional diagnostics, but not logspew
     static final boolean CHATTY =  Log.isLoggable(TAG + "Chat", Log.DEBUG);
 
+    private static final int EMERGENCY_NO_CONTROLLERS = 0;
+    private static final int EMERGENCY_FIRST_CONTROLLER = 100;
+    private static final int EMERGENCY_VOICE_CONTROLLER = 200;
+    private static final int EMERGENCY_NO_SUB = 300;
+
     private final Context mContext;
     private final TelephonyManager mPhone;
     private final WifiManager mWifiManager;
@@ -118,6 +123,9 @@
     // Handler that all callbacks are made on.
     private final CallbackHandler mCallbackHandler;
 
+    private int mEmergencySource;
+    private boolean mIsEmergency;
+
     @VisibleForTesting
     ServiceState mLastServiceState;
 
@@ -267,6 +275,7 @@
         if (mMobileSignalControllers.size() == 0) {
             // When there are no active subscriptions, determine emengency state from last
             // broadcast.
+            mEmergencySource = EMERGENCY_NO_CONTROLLERS;
             return mLastServiceState != null && mLastServiceState.isEmergencyOnly();
         }
         int voiceSubId = mSubDefaults.getDefaultVoiceSubId();
@@ -274,16 +283,20 @@
             for (MobileSignalController mobileSignalController :
                                             mMobileSignalControllers.values()) {
                 if (!mobileSignalController.getState().isEmergency) {
+                    mEmergencySource = EMERGENCY_FIRST_CONTROLLER
+                            + mobileSignalController.mSubscriptionInfo.getSubscriptionId();
                     if (DEBUG) Log.d(TAG, "Found emergency " + mobileSignalController.mTag);
                     return false;
                 }
             }
         }
         if (mMobileSignalControllers.containsKey(voiceSubId)) {
+            mEmergencySource = EMERGENCY_VOICE_CONTROLLER + voiceSubId;
             if (DEBUG) Log.d(TAG, "Getting emergency from " + voiceSubId);
             return mMobileSignalControllers.get(voiceSubId).getState().isEmergency;
         }
         if (DEBUG) Log.e(TAG, "Cannot find controller for voice sub: " + voiceSubId);
+        mEmergencySource = EMERGENCY_NO_SUB + voiceSubId;
         // Something is wrong, better assume we can't make calls...
         return true;
     }
@@ -293,7 +306,8 @@
      * so we should recheck and send out the state to listeners.
      */
     void recalculateEmergency() {
-        mCallbackHandler.setEmergencyCallsOnly(isEmergencyOnly());
+        mIsEmergency = isEmergencyOnly();
+        mCallbackHandler.setEmergencyCallsOnly(mIsEmergency);
     }
 
     public void addSignalCallback(SignalCallback cb) {
@@ -606,6 +620,10 @@
         pw.println(mLocale);
         pw.print("  mLastServiceState=");
         pw.println(mLastServiceState);
+        pw.print("  mIsEmergency=");
+        pw.println(mIsEmergency);
+        pw.print("  mEmergencySource=");
+        pw.println(emergencyToString(mEmergencySource));
 
         for (MobileSignalController mobileSignalController : mMobileSignalControllers.values()) {
             mobileSignalController.dump(pw);
@@ -617,6 +635,19 @@
         mAccessPoints.dump(pw);
     }
 
+    private static final String emergencyToString(int emergencySource) {
+        if (emergencySource > EMERGENCY_NO_SUB) {
+            return "NO_SUB(" + (emergencySource - EMERGENCY_NO_SUB) + ")";
+        } else if (emergencySource > EMERGENCY_VOICE_CONTROLLER) {
+            return "VOICE_CONTROLLER(" + (emergencySource - EMERGENCY_VOICE_CONTROLLER) + ")";
+        } else if (emergencySource > EMERGENCY_FIRST_CONTROLLER) {
+            return "FIRST_CONTROLLER(" + (emergencySource - EMERGENCY_FIRST_CONTROLLER) + ")";
+        } else if (emergencySource == EMERGENCY_NO_CONTROLLERS) {
+            return "NO_CONTROLLERS";
+        }
+        return "UNKNOWN_SOURCE";
+    }
+
     private boolean mDemoMode;
     private boolean mDemoInetCondition;
     private WifiSignalController.WifiState mDemoWifiState;