Fix wake and scan behavior

- Add wakelock for driver start/stop to ensure a wifilock
  acquisition kick starts driver. Also cleaned up state machine
  driver start/stop behavior.
- Add periodic scans when driver is started to ensure wifi
  reconnections when wifilock exists or when user chooses
  never to sleep
- some minor clean up

Change-Id: I844eb70491d5aa2f8c8933b3d8dd01ba237ee534

1 files changed, 28 insertions, 10 deletions

diff --git a/services/java/com/android/server/WifiService.java b/services/java/com/android/server/WifiService.java
index 55b7c9e..1241a7e 100644
--- a/services/java/com/android/server/WifiService.java
+++ b/services/java/com/android/server/WifiService.java
@@ -88,8 +88,10 @@ public class WifiService extends IWifiManager.Stub {
 
     private AlarmManager mAlarmManager;
     private PendingIntent mIdleIntent;
+    private PendingIntent mScanIntent;
     private BluetoothA2dp mBluetoothA2dp;
     private static final int IDLE_REQUEST = 0;
+    private static final int SCAN_REQUEST = 0;
     private boolean mScreenOff;
     private boolean mDeviceIdle;
     private int mPluggedType;
@@ -121,7 +123,13 @@ public class WifiService extends IWifiManager.Stub {
      * being enabled but not active exceeds the battery drain caused by
      * re-establishing a connection to the mobile data network.
      */
-    private static final long DEFAULT_IDLE_MILLIS = 15 * 60 * 1000; /* 15 minutes */
+    private static final long DEFAULT_IDLE_MS = 15 * 60 * 1000; /* 15 minutes */
+
+    /**
+     * See {@link Settings.Secure#WIFI_SCAN_INTERVAL_MS}. This is the default value if a
+     * Settings.Secure value is not present.
+     */
+    private static final long DEFAULT_SCAN_INTERVAL_MS = 60 * 1000; /* 1 minute */
 
     /**
      * Number of allowed radio frequency channels in various regulatory domains.
@@ -132,6 +140,9 @@ public class WifiService extends IWifiManager.Stub {
     private static final String ACTION_DEVICE_IDLE =
             "com.android.server.WifiManager.action.DEVICE_IDLE";
 
+    private static final String ACTION_START_SCAN =
+        "com.android.server.WifiManager.action.START_SCAN";
+
     private boolean mIsReceiverRegistered = false;
 
 
@@ -202,6 +213,9 @@ public class WifiService extends IWifiManager.Stub {
         Intent idleIntent = new Intent(ACTION_DEVICE_IDLE, null);
         mIdleIntent = PendingIntent.getBroadcast(mContext, IDLE_REQUEST, idleIntent, 0);
 
+        Intent scanIntent = new Intent(ACTION_START_SCAN, null);
+        mScanIntent = PendingIntent.getBroadcast(mContext, SCAN_REQUEST, scanIntent, 0);
+
         HandlerThread wifiThread = new HandlerThread("WifiService");
         wifiThread.start();
 
@@ -824,7 +838,7 @@ public class WifiService extends IWifiManager.Stub {
 
             long idleMillis =
                 Settings.Secure.getLong(mContext.getContentResolver(),
-                                        Settings.Secure.WIFI_IDLE_MS, DEFAULT_IDLE_MILLIS);
+                                        Settings.Secure.WIFI_IDLE_MS, DEFAULT_IDLE_MS);
             int stayAwakeConditions =
                 Settings.System.getInt(mContext.getContentResolver(),
                                        Settings.System.STAY_ON_WHILE_PLUGGED_IN, 0);
@@ -837,6 +851,7 @@ public class WifiService extends IWifiManager.Stub {
                 // because of any locks so clear that tracking immediately.
                 reportStartWorkSource();
                 mWifiStateMachine.enableRssiPolling(true);
+                updateWifiState();
             } else if (action.equals(Intent.ACTION_SCREEN_OFF)) {
                 Slog.d(TAG, "ACTION_SCREEN_OFF");
                 mScreenOff = true;
@@ -866,12 +881,11 @@ public class WifiService extends IWifiManager.Stub {
                         mAlarmManager.set(AlarmManager.RTC_WAKEUP, triggerTime, mIdleIntent);
                     }
                 }
-                /* we can return now -- there's nothing to do until we get the idle intent back */
-                return;
             } else if (action.equals(ACTION_DEVICE_IDLE)) {
                 Slog.d(TAG, "got ACTION_DEVICE_IDLE");
                 mDeviceIdle = true;
                 reportStartWorkSource();
+                updateWifiState();
             } else if (action.equals(Intent.ACTION_BATTERY_CHANGED)) {
                 /*
                  * Set a timer to put Wi-Fi to sleep, but only if the screen is off
@@ -886,19 +900,15 @@ public class WifiService extends IWifiManager.Stub {
                     long triggerTime = System.currentTimeMillis() + idleMillis;
                     Slog.d(TAG, "setting ACTION_DEVICE_IDLE timer for " + idleMillis + "ms");
                     mAlarmManager.set(AlarmManager.RTC_WAKEUP, triggerTime, mIdleIntent);
-                    mPluggedType = pluggedType;
-                    return;
                 }
                 mPluggedType = pluggedType;
             } else if (action.equals(BluetoothA2dp.ACTION_PLAYING_STATE_CHANGED)) {
                 int state = intent.getIntExtra(BluetoothProfile.EXTRA_STATE,
                                                BluetoothA2dp.STATE_NOT_PLAYING);
                 mWifiStateMachine.setBluetoothScanMode(state == BluetoothA2dp.STATE_PLAYING);
-            } else {
-                return;
+            } else if (action.equals(ACTION_START_SCAN)) {
+                mWifiStateMachine.startScan(true);
             }
-
-            updateWifiState();
         }
 
         /**
@@ -967,6 +977,10 @@ public class WifiService extends IWifiManager.Stub {
             strongestLockMode = WifiManager.WIFI_MODE_FULL;
         }
 
+        /* Scan interval when driver is started */
+        long scanMs = Settings.Secure.getLong(mContext.getContentResolver(),
+                Settings.Secure.WIFI_SCAN_INTERVAL_MS, DEFAULT_SCAN_INTERVAL_MS);
+
         /* Disable tethering when airplane mode is enabled */
         if (airplaneMode) {
             mWifiStateMachine.setWifiApEnabled(null, false);
@@ -979,9 +993,12 @@ public class WifiService extends IWifiManager.Stub {
                 mWifiStateMachine.setScanOnlyMode(
                         strongestLockMode == WifiManager.WIFI_MODE_SCAN_ONLY);
                 mWifiStateMachine.setDriverStart(true);
+                mAlarmManager.setRepeating(AlarmManager.RTC_WAKEUP,
+                        System.currentTimeMillis() + scanMs, scanMs, mScanIntent);
             } else {
                 mWifiStateMachine.requestCmWakeLock();
                 mWifiStateMachine.setDriverStart(false);
+                mAlarmManager.cancel(mScanIntent);
             }
         } else {
             mWifiStateMachine.setWifiEnabled(false);
@@ -994,6 +1011,7 @@ public class WifiService extends IWifiManager.Stub {
         intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
         intentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
         intentFilter.addAction(ACTION_DEVICE_IDLE);
+        intentFilter.addAction(ACTION_START_SCAN);
         intentFilter.addAction(BluetoothA2dp.ACTION_PLAYING_STATE_CHANGED);
         mContext.registerReceiver(mReceiver, intentFilter);
     }