2 files changed, 65 insertions, 3 deletions

diff --git a/core/java/com/android/internal/display/RefreshRateSettingsUtils.java b/core/java/com/android/internal/display/RefreshRateSettingsUtils.java
index fab8984ce067..c23a5012923b 100644
--- a/core/java/com/android/internal/display/RefreshRateSettingsUtils.java
+++ b/core/java/com/android/internal/display/RefreshRateSettingsUtils.java
@@ -16,6 +16,8 @@
 
 package com.android.internal.display;
 
+import static android.hardware.display.DisplayManager.DISPLAY_CATEGORY_ALL_INCLUDING_DISABLED;
+
 import android.content.Context;
 import android.hardware.display.DisplayManager;
 import android.util.Log;
@@ -54,4 +56,31 @@ public class RefreshRateSettingsUtils {
         }
         return maxRefreshRate;
     }
+
+    /**
+     * Find the highest refresh rate among all the modes of all the displays.
+     *
+     * This method will acquire DisplayManager.mLock, so calling it while holding other locks
+     * should be done with care.
+     * @param context The context
+     * @return The highest refresh rate
+     */
+    public static float findHighestRefreshRateAmongAllDisplays(Context context) {
+        final DisplayManager dm = context.getSystemService(DisplayManager.class);
+        final Display[] displays = dm.getDisplays(DISPLAY_CATEGORY_ALL_INCLUDING_DISABLED);
+        if (displays.length == 0) {
+            Log.w(TAG, "No valid display devices");
+            return DEFAULT_REFRESH_RATE;
+        }
+
+        float maxRefreshRate = DEFAULT_REFRESH_RATE;
+        for (Display display : displays) {
+            for (Display.Mode mode : display.getSupportedModes()) {
+                if (mode.getRefreshRate() > maxRefreshRate) {
+                    maxRefreshRate = mode.getRefreshRate();
+                }
+            }
+        }
+        return maxRefreshRate;
+    }
 }
diff --git a/services/tests/displayservicetests/src/com/android/server/display/RefreshRateSettingsUtilsTest.java b/services/tests/displayservicetests/src/com/android/server/display/RefreshRateSettingsUtilsTest.java
index a8af98f7a332..8a6c2440a232 100644
--- a/services/tests/displayservicetests/src/com/android/server/display/RefreshRateSettingsUtilsTest.java
+++ b/services/tests/displayservicetests/src/com/android/server/display/RefreshRateSettingsUtilsTest.java
@@ -16,6 +16,8 @@
 
 package com.android.server.display;
 
+import static android.hardware.display.DisplayManager.DISPLAY_CATEGORY_ALL_INCLUDING_DISABLED;
+
 import static com.android.internal.display.RefreshRateSettingsUtils.DEFAULT_REFRESH_RATE;
 
 import static org.junit.Assert.assertEquals;
@@ -50,6 +52,8 @@ public class RefreshRateSettingsUtilsTest {
     private DisplayManager mDisplayManagerMock;
     @Mock
     private Display mDisplayMock;
+    @Mock
+    private Display mDisplayMock2;
 
     @Before
     public void setUp() {
@@ -65,25 +69,54 @@ public class RefreshRateSettingsUtilsTest {
                 new Display.Mode(/* modeId= */ 0, /* width= */ 800, /* height= */ 600,
                         /* refreshRate= */ 90)
         };
-
         when(mDisplayManagerMock.getDisplay(Display.DEFAULT_DISPLAY)).thenReturn(mDisplayMock);
         when(mDisplayMock.getSupportedModes()).thenReturn(modes);
+
+        Display.Mode[] modes2 = new Display.Mode[]{
+                new Display.Mode(/* modeId= */ 0, /* width= */ 800, /* height= */ 600,
+                        /* refreshRate= */ 70),
+                new Display.Mode(/* modeId= */ 0, /* width= */ 800, /* height= */ 600,
+                        /* refreshRate= */ 130),
+                new Display.Mode(/* modeId= */ 0, /* width= */ 800, /* height= */ 600,
+                        /* refreshRate= */ 80)
+        };
+        when(mDisplayManagerMock.getDisplay(Display.DEFAULT_DISPLAY + 1)).thenReturn(mDisplayMock2);
+        when(mDisplayMock2.getSupportedModes()).thenReturn(modes2);
+
+        when(mDisplayManagerMock.getDisplays(DISPLAY_CATEGORY_ALL_INCLUDING_DISABLED))
+                .thenReturn(new Display[]{ mDisplayMock, mDisplayMock2 });
     }
 
     @Test
     public void testFindHighestRefreshRateForDefaultDisplay() {
-        when(mDisplayManagerMock.getDisplay(Display.DEFAULT_DISPLAY)).thenReturn(mDisplayMock);
         assertEquals(120,
                 RefreshRateSettingsUtils.findHighestRefreshRateForDefaultDisplay(mContext),
                 /* delta= */ 0);
     }
 
     @Test
-    public void testFindHighestRefreshRate_DisplayIsNull() {
+    public void testFindHighestRefreshRateForDefaultDisplay_DisplayIsNull() {
         when(mDisplayManagerMock.getDisplay(Display.DEFAULT_DISPLAY)).thenReturn(null);
         assertEquals(DEFAULT_REFRESH_RATE,
                 RefreshRateSettingsUtils.findHighestRefreshRateForDefaultDisplay(mContext),
                 /* delta= */ 0);
 
     }
+
+    @Test
+    public void testFindHighestRefreshRateAmongAllDisplays() {
+        assertEquals(130,
+                RefreshRateSettingsUtils.findHighestRefreshRateAmongAllDisplays(mContext),
+                /* delta= */ 0);
+    }
+
+    @Test
+    public void testFindHighestRefreshRateAmongAllDisplays_NoDisplays() {
+        when(mDisplayManagerMock.getDisplays(DISPLAY_CATEGORY_ALL_INCLUDING_DISABLED))
+                .thenReturn(new Display[0]);
+        assertEquals(DEFAULT_REFRESH_RATE,
+                RefreshRateSettingsUtils.findHighestRefreshRateAmongAllDisplays(mContext),
+                /* delta= */ 0);
+
+    }
 }