Fix USB tethering

The previous approach no longer works with the new USB drivers, since the usb0
interface is no longer enabled by default.
This introduced a chicken & egg problem - usb0 will not be enabled until the
user tries to start tethering, but Settings will not enable the checkbox unless
usb0 is enabled.
To fix this we add an explicit call to start USB tethering in the connectivity manager.
This will enable RNDIS if necessary and then bring up tethering once usb0 is enabled.

Change-Id: If3972c89e05377af00b7a71cc2588e44bd4cfaed
Signed-off-by: Mike Lockwood <lockwood@android.com>

1 files changed, 27 insertions, 39 deletions

diff --git a/src/com/android/settings/TetherSettings.java b/src/com/android/settings/TetherSettings.java
index 1513d43..9991725 100644
--- a/src/com/android/settings/TetherSettings.java
+++ b/src/com/android/settings/TetherSettings.java
@@ -31,6 +31,7 @@ import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.res.AssetManager;
+import android.hardware.usb.UsbManager;
 import android.net.ConnectivityManager;
 import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiManager;
@@ -95,6 +96,9 @@ public class TetherSettings extends SettingsPreferenceFragment
     private WifiManager mWifiManager;
     private WifiConfiguration mWifiConfig = null;
 
+    private boolean mUsbConnected;
+    private boolean mMassStorageActive;
+
     private boolean mBluetoothEnableForTether;
 
     @Override
@@ -253,8 +257,14 @@ public class TetherSettings extends SettingsPreferenceFragment
                 updateState(available.toArray(new String[available.size()]),
                         active.toArray(new String[active.size()]),
                         errored.toArray(new String[errored.size()]));
-            } else if (action.equals(Intent.ACTION_MEDIA_SHARED) ||
-                       action.equals(Intent.ACTION_MEDIA_UNSHARED)) {
+            } else if (action.equals(Intent.ACTION_MEDIA_SHARED)) {
+                mMassStorageActive = true;
+                updateState();
+            } else if (action.equals(Intent.ACTION_MEDIA_UNSHARED)) {
+                mMassStorageActive = false;
+                updateState();
+            } else if (action.equals(UsbManager.ACTION_USB_STATE)) {
+                mUsbConnected = intent.getBooleanExtra(UsbManager.USB_CONNECTED, false);
                 updateState();
             } else if (action.equals(BluetoothAdapter.ACTION_STATE_CHANGED)) {
                 if (mBluetoothEnableForTether) {
@@ -285,11 +295,16 @@ public class TetherSettings extends SettingsPreferenceFragment
 
         final Activity activity = getActivity();
 
+        mMassStorageActive = Environment.MEDIA_SHARED.equals(Environment.getExternalStorageState());
         mTetherChangeReceiver = new TetherChangeReceiver();
         IntentFilter filter = new IntentFilter(ConnectivityManager.ACTION_TETHER_STATE_CHANGED);
         Intent intent = activity.registerReceiver(mTetherChangeReceiver, filter);
 
         filter = new IntentFilter();
+        filter.addAction(UsbManager.ACTION_USB_STATE);
+        activity.registerReceiver(mTetherChangeReceiver, filter);
+
+        filter = new IntentFilter();
         filter.addAction(Intent.ACTION_MEDIA_SHARED);
         filter.addAction(Intent.ACTION_MEDIA_UNSHARED);
         filter.addDataScheme("file");
@@ -334,14 +349,11 @@ public class TetherSettings extends SettingsPreferenceFragment
             String[] errored) {
         ConnectivityManager cm =
                 (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
-        boolean usbAvailable = false;
+        boolean usbAvailable = mUsbConnected && !mMassStorageActive;
         int usbError = ConnectivityManager.TETHER_ERROR_NO_ERROR;
-        boolean massStorageActive =
-                Environment.MEDIA_SHARED.equals(Environment.getExternalStorageState());
         for (String s : available) {
             for (String regex : mUsbRegexs) {
                 if (s.matches(regex)) {
-                    usbAvailable = true;
                     if (usbError == ConnectivityManager.TETHER_ERROR_NO_ERROR) {
                         usbError = cm.getLastTetherError(s);
                     }
@@ -377,7 +389,7 @@ public class TetherSettings extends SettingsPreferenceFragment
             mUsbTether.setSummary(R.string.usb_tethering_errored_subtext);
             mUsbTether.setEnabled(false);
             mUsbTether.setChecked(false);
-        } else if (massStorageActive) {
+        } else if (mMassStorageActive) {
             mUsbTether.setSummary(R.string.usb_tethering_storage_active_subtext);
             mUsbTether.setEnabled(false);
             mUsbTether.setChecked(false);
@@ -434,40 +446,18 @@ public class TetherSettings extends SettingsPreferenceFragment
 
     @Override
     public boolean onPreferenceTreeClick(PreferenceScreen screen, Preference preference) {
+        ConnectivityManager cm =
+                (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
+
         if (preference == mUsbTether) {
             boolean newState = mUsbTether.isChecked();
 
-            ConnectivityManager cm =
-                    (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
-
-            if (newState) {
-                String[] available = cm.getTetherableIfaces();
-
-                String usbIface = findIface(available, mUsbRegexs);
-                if (usbIface == null) {
-                    updateState();
-                    return true;
-                }
-                if (cm.tether(usbIface) != ConnectivityManager.TETHER_ERROR_NO_ERROR) {
-                    mUsbTether.setChecked(false);
-                    mUsbTether.setSummary(R.string.usb_tethering_errored_subtext);
-                    return true;
-                }
-                mUsbTether.setSummary("");
-            } else {
-                String [] tethered = cm.getTetheredIfaces();
-
-                String usbIface = findIface(tethered, mUsbRegexs);
-                if (usbIface == null) {
-                    updateState();
-                    return true;
-                }
-                if (cm.untether(usbIface) != ConnectivityManager.TETHER_ERROR_NO_ERROR) {
-                    mUsbTether.setSummary(R.string.usb_tethering_errored_subtext);
-                    return true;
-                }
-                mUsbTether.setSummary("");
+            if (cm.setUsbTethering(newState) != ConnectivityManager.TETHER_ERROR_NO_ERROR) {
+                mUsbTether.setChecked(false);
+                mUsbTether.setSummary(R.string.usb_tethering_errored_subtext);
+                return true;
             }
+            mUsbTether.setSummary("");
         } else if (preference == mBluetoothTether) {
             boolean bluetoothTetherState = mBluetoothTether.isChecked();
 
@@ -486,8 +476,6 @@ public class TetherSettings extends SettingsPreferenceFragment
             } else {
                 boolean errored = false;
 
-                ConnectivityManager cm =
-                    (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
                 String [] tethered = cm.getTetheredIfaces();
                 String bluetoothIface = findIface(tethered, mBluetoothRegexs);
                 if (bluetoothIface != null &&