diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 0a088e9..381fe89 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -3121,10 +3121,7 @@
                 Settings.Global.TETHER_SUPPORTED, defaultVal) != 0)
                 && !mUserManager.hasUserRestriction(UserManager.DISALLOW_CONFIG_TETHERING);
         return tetherEnabledInSettings && mUserManager.isAdminUser() &&
-                ((mTethering.getTetherableUsbRegexs().length != 0 ||
-                mTethering.getTetherableWifiRegexs().length != 0 ||
-                mTethering.getTetherableBluetoothRegexs().length != 0) &&
-                mTethering.getUpstreamIfaceTypes().length != 0);
+               mTethering.hasTetherableConfiguration();
     }
 
     @Override
diff --git a/services/core/java/com/android/server/connectivity/Tethering.java b/services/core/java/com/android/server/connectivity/Tethering.java
index 611b7a8..b82dd60 100644
--- a/services/core/java/com/android/server/connectivity/Tethering.java
+++ b/services/core/java/com/android/server/connectivity/Tethering.java
@@ -205,7 +205,7 @@
         return (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE);
     }
 
-    void updateConfiguration() {
+    private void updateConfiguration() {
         mConfig = new TetheringConfiguration(mContext);
     }
 
@@ -817,6 +817,17 @@
         return mConfig;
     }
 
+    public boolean hasTetherableConfiguration() {
+        final TetheringConfiguration cfg = mConfig;
+        final boolean hasDownstreamConfiguration =
+                (cfg.tetherableUsbRegexs.length != 0) ||
+                (cfg.tetherableWifiRegexs.length != 0) ||
+                (cfg.tetherableBluetoothRegexs.length != 0);
+        final boolean hasUpstreamConfiguration = !cfg.preferredUpstreamIfaceTypes.isEmpty();
+
+        return hasDownstreamConfiguration && hasUpstreamConfiguration;
+    }
+
     // TODO - update callers to use getTetheringConfiguration(),
     // which has only final members.
     public String[] getTetherableUsbRegexs() {
@@ -864,17 +875,6 @@
         return ConnectivityManager.TETHER_ERROR_NO_ERROR;
     }
 
-    public int[] getUpstreamIfaceTypes() {
-        updateConfiguration();  // TODO - remove?
-        final Collection<Integer> upstreams = mConfig.preferredUpstreamIfaceTypes;
-        final int[] values = new int[upstreams.size()];
-        int i = 0;
-        for (Integer u : upstreams) {
-            values[i++] = u.intValue();
-        }
-        return values;
-    }
-
     // TODO review API - maybe return ArrayList<String> here and below?
     public String[] getTetheredIfaces() {
         ArrayList<String> list = new ArrayList<String>();