1 files changed, 28 insertions, 5 deletions
diff --git a/core/java/android/hardware/display/DisplayManagerGlobal.java b/core/java/android/hardware/display/DisplayManagerGlobal.java
index 936a0867fd83..34174301ac8e 100644
--- a/core/java/android/hardware/display/DisplayManagerGlobal.java
+++ b/core/java/android/hardware/display/DisplayManagerGlobal.java
@@ -72,6 +72,8 @@ public final class DisplayManagerGlobal {
     private final SparseArray<DisplayInfo> mDisplayInfoCache = new SparseArray<DisplayInfo>();
     private int[] mDisplayIdCache;
 
+    private int mWifiDisplayScanNestCount;
+
     private DisplayManagerGlobal(IDisplayManager dm) {
         mDm = dm;
     }
@@ -267,11 +269,32 @@ public final class DisplayManagerGlobal {
         }
     }
 
-    public void scanWifiDisplays() {
-        try {
-            mDm.scanWifiDisplays();
-        } catch (RemoteException ex) {
-            Log.e(TAG, "Failed to scan for Wifi displays.", ex);
+    public void startWifiDisplayScan() {
+        synchronized (mLock) {
+            if (mWifiDisplayScanNestCount++ == 0) {
+                registerCallbackIfNeededLocked();
+                try {
+                    mDm.startWifiDisplayScan();
+                } catch (RemoteException ex) {
+                    Log.e(TAG, "Failed to scan for Wifi displays.", ex);
+                }
+            }
+        }
+    }
+
+    public void stopWifiDisplayScan() {
+        synchronized (mLock) {
+            if (--mWifiDisplayScanNestCount == 0) {
+                try {
+                    mDm.stopWifiDisplayScan();
+                } catch (RemoteException ex) {
+                    Log.e(TAG, "Failed to scan for Wifi displays.", ex);
+                }
+            } else if (mWifiDisplayScanNestCount < 0) {
+                Log.wtf(TAG, "Wifi display scan nest count became negative: "
+                        + mWifiDisplayScanNestCount);
+                mWifiDisplayScanNestCount = 0;
+            }
         }
     }