1 files changed, 15 insertions, 6 deletions
diff --git a/services/java/com/android/server/SensorService.java b/services/java/com/android/server/SensorService.java
index ceef39f93ff9..4dfeb9d51b8d 100644
--- a/services/java/com/android/server/SensorService.java
+++ b/services/java/com/android/server/SensorService.java
@@ -84,12 +84,16 @@ class SensorService extends ISensorService.Stub {
                     if (hasSensor(sensor)) {
                         removeSensor(sensor);
                         try {
-                            deactivateIfUnused(sensor);
+                            deactivateIfUnusedLocked(sensor);
                         } catch (RemoteException e) {
                             Log.w(TAG, "RemoteException in binderDied");
                         }
                     }
                 }
+                if (mListeners.size() == 0) {
+                    _sensors_control_wake();
+                    _sensors_control_close();
+                }
                 mListeners.notify();
             }
         }
@@ -102,9 +106,12 @@ class SensorService extends ISensorService.Stub {
     }
     
     public Bundle getDataChannel() throws RemoteException {
-        return _sensors_control_open();
+        // synchronize so we do not require sensor HAL to be thread-safe.
+        synchronized(mListeners) {
+            return _sensors_control_open();
+        }
     }
-    
+
     public boolean enableSensor(IBinder binder, String name, int sensor, int enable)
              throws RemoteException {
         if (localLOGV) Log.d(TAG, "enableSensor " + name + "(#" + sensor + ") " + enable);
@@ -163,7 +170,7 @@ class SensorService extends ISensorService.Stub {
                 l.addSensor(sensor, enable);
             } else {
                 l.removeSensor(sensor);
-                deactivateIfUnused(sensor);
+                deactivateIfUnusedLocked(sensor);
                 if (l.mSensors == 0) {
                     mListeners.remove(l);
                     binder.unlinkToDeath(l, 0);
@@ -173,12 +180,13 @@ class SensorService extends ISensorService.Stub {
             
             if (mListeners.size() == 0) {
                 _sensors_control_wake();
+                _sensors_control_close();
             }
         }        
         return true;
     }
 
-    void deactivateIfUnused(int sensor) throws RemoteException {
+    private void deactivateIfUnusedLocked(int sensor) throws RemoteException {
         int size = mListeners.size();
         for (int i=0 ; i<size ; i++) {
             if (mListeners.get(i).hasSensor(sensor))
@@ -187,10 +195,11 @@ class SensorService extends ISensorService.Stub {
         _sensors_control_activate(sensor, false);
     }
 
-    ArrayList<Listener> mListeners = new ArrayList<Listener>();
+    private ArrayList<Listener> mListeners = new ArrayList<Listener>();
 
     private static native int _sensors_control_init();
     private static native Bundle _sensors_control_open();
+    private static native int _sensors_control_close();
     private static native boolean _sensors_control_activate(int sensor, boolean activate);
     private static native int _sensors_control_set_delay(int ms);
     private static native int _sensors_control_wake();