Fix WakeLock issue for driver stop

Due to message removal, wakelock could be held forever.

Do a timer only based wakelock release until we do this
more cleanly in ConnectivityService for later release.

Also, add an optimization to prevent use of wakelocks when driver is
already stopped.

Bug: 2529883
Change-Id: Ia1c2ddd44213ef3aa609855613bf155945bef8e4

1 files changed, 21 insertions, 24 deletions

diff --git a/wifi/java/android/net/wifi/WifiStateTracker.java b/wifi/java/android/net/wifi/WifiStateTracker.java
index 80b8aed..4f84aab 100644
--- a/wifi/java/android/net/wifi/WifiStateTracker.java
+++ b/wifi/java/android/net/wifi/WifiStateTracker.java
@@ -313,8 +313,6 @@ public class WifiStateTracker extends NetworkStateTracker {
     private String mInterfaceName;
     private static String LS = System.getProperty("line.separator");
 
-    private Runnable mReleaseWakeLockCallback;
-
     private static String[] sDnsPropNames;
 
     /**
@@ -615,7 +613,15 @@ public class WifiStateTracker extends NetworkStateTracker {
         }
     }
 
-    private synchronized boolean isDriverStopped() {
+    /**
+     * TODO: mRunState is not synchronized in some places
+     * address this as part of re-architect.
+     *
+     * TODO: We are exposing an additional public synchronized call
+     * for a wakelock optimization in WifiService. Remove it
+     * when we handle the wakelock in ConnectivityService.
+     */
+    public synchronized boolean isDriverStopped() {
         return mRunState == RUN_STATE_STOPPED || mRunState == RUN_STATE_STOPPING;
     }
 
@@ -674,15 +680,20 @@ public class WifiStateTracker extends NetworkStateTracker {
         }
     }
 
+    /**
+     * We release the wakelock in WifiService
+     * using a timer.
+     *
+     * TODO:
+     * Releasing wakelock using both timer and
+     * a call from ConnectivityService requires
+     * a rethink. We had problems where WifiService
+     * could keep a wakelock forever if we delete
+     * messages in the asynchronous call
+     * from ConnectivityService
+     */
     @Override
     public void releaseWakeLock() {
-        if (mReleaseWakeLockCallback != null) {
-            mReleaseWakeLockCallback.run();
-        }
-    }
-    
-    public void setReleaseWakeLockCallback(Runnable callback) {
-        mReleaseWakeLockCallback = callback;
     }
 
     /**
@@ -1481,20 +1492,6 @@ public class WifiStateTracker extends NetworkStateTracker {
             } else {
                 return disconnect();
             }
-        } else {
-            /*
-             * The "driver-stop" wake lock normally is released from the
-             * connectivity manager after the mobile data connection has
-             * been established, or after a timeout period, if that never
-             * happens. Because WifiService.updateWifiState() can get called
-             * multiple times, we can end up acquiring the wake lock and calling
-             * disconnectAndStop() even when a disconnect or stop operation
-             * is already in progress. In that case, we want to ignore the
-             * disconnectAndStop request and release the (ref-counted) wake
-             * lock, so that eventually, when the mobile data connection is
-             * established, the ref count will drop to zero.
-             */
-            releaseWakeLock();
         }
         return true;
     }