Support "Mute" and "Restore Volume" CEC commands

Adds support for <User Control Pressed> ["Mute Function"] and ["Restore
Volume Function"] on all HDMI devices. These commands are currently
ignored because they are not mapped to an Android keycode.

Support for these commands is required for HDMI CEC 2.0.

Bug: 191230341
Test: Manual; atest HdmiCecLocalDeviceTest
Change-Id: I5146e9e99595a9a124e0ce2176f5e70a29923a49

services/core/java/com/android/server/hdmi/HdmiCecLocalDevice.java

@@ -23,6 +23,7 @@ import android.hardware.hdmi.HdmiDeviceInfo;
 import android.hardware.hdmi.IHdmiControlCallback;
 import android.hardware.input.InputManager;
 import android.hardware.tv.cec.V1_0.SendMessageResult;
+import android.media.AudioManager;
 import android.os.Handler;
 import android.os.Looper;
 import android.os.Message;
@@ -685,11 +686,29 @@ abstract class HdmiCecLocalDevice {
                     Message.obtain(mHandler, MSG_USER_CONTROL_RELEASE_TIMEOUT),
                     FOLLOWER_SAFETY_TIMEOUT);
             return Constants.HANDLED;
+        } else if (params.length > 0) {
+            // Handle CEC UI commands that are not mapped to an Android keycode
+            return handleUnmappedCecKeycode(params[0]);
         }
 
         return Constants.ABORT_INVALID_OPERAND;
     }
 
+    @ServiceThreadOnly
+    @Constants.HandleMessageResult
+    protected int handleUnmappedCecKeycode(int cecKeycode) {
+        if (cecKeycode == HdmiCecKeycode.CEC_KEYCODE_MUTE_FUNCTION) {
+            mService.getAudioManager().adjustStreamVolume(AudioManager.STREAM_MUSIC,
+                    AudioManager.ADJUST_MUTE, AudioManager.FLAG_SHOW_UI);
+            return Constants.HANDLED;
+        } else if (cecKeycode == HdmiCecKeycode.CEC_KEYCODE_RESTORE_VOLUME_FUNCTION) {
+            mService.getAudioManager().adjustStreamVolume(AudioManager.STREAM_MUSIC,
+                    AudioManager.ADJUST_UNMUTE, AudioManager.FLAG_SHOW_UI);
+            return Constants.HANDLED;
+        }
+        return Constants.ABORT_INVALID_OPERAND;
+    }
+
     @ServiceThreadOnly
     @Constants.HandleMessageResult
     protected int handleUserControlReleased() {

services/tests/servicestests/src/com/android/server/hdmi/HdmiCecLocalDeviceTest.java

@@ -32,9 +32,15 @@ import static junit.framework.Assert.assertEquals;
 import static junit.framework.Assert.assertFalse;
 import static junit.framework.Assert.assertTrue;
 
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
 import android.content.Context;
 import android.hardware.hdmi.HdmiControlManager;
 import android.hardware.hdmi.HdmiPortInfo;
+import android.media.AudioManager;
 import android.os.test.TestLooper;
 import android.platform.test.annotations.Presubmit;
 
@@ -45,6 +51,8 @@ import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -123,8 +131,12 @@ public class HdmiCecLocalDeviceTest {
     private boolean isControlEnabled;
     private int mPowerStatus;
 
+    @Mock
+    private AudioManager mAudioManager;
+
     @Before
     public void SetUp() {
+        MockitoAnnotations.initMocks(this);
 
         Context context = InstrumentationRegistry.getTargetContext();
 
@@ -161,6 +173,11 @@ public class HdmiCecLocalDeviceTest {
                     void wakeUp() {
                         mWakeupMessageReceived = true;
                     }
+
+                    @Override
+                    AudioManager getAudioManager() {
+                        return mAudioManager;
+                    }
                 };
         mHdmiControlService.setIoLooper(mTestLooper.getLooper());
         mHdmiControlService.setHdmiCecConfig(new FakeHdmiCecConfig(context));
@@ -418,6 +435,28 @@ public class HdmiCecLocalDeviceTest {
         assertThat(mStandbyMessageReceived).isTrue();
     }
 
+    @Test
+    public void handleUserControlPressed_muteFunction() {
+        @Constants.HandleMessageResult int result = mHdmiLocalDevice.handleUserControlPressed(
+                HdmiCecMessageBuilder.buildUserControlPressed(ADDR_TV, ADDR_PLAYBACK_1,
+                        HdmiCecKeycode.CEC_KEYCODE_MUTE_FUNCTION));
+
+        assertEquals(result, Constants.HANDLED);
+        verify(mAudioManager, times(1))
+                .adjustStreamVolume(anyInt(), eq(AudioManager.ADJUST_MUTE), anyInt());
+    }
+
+    @Test
+    public void handleUserControlPressed_restoreVolumeFunction() {
+        @Constants.HandleMessageResult int result = mHdmiLocalDevice.handleUserControlPressed(
+                HdmiCecMessageBuilder.buildUserControlPressed(ADDR_TV, ADDR_PLAYBACK_1,
+                        HdmiCecKeycode.CEC_KEYCODE_RESTORE_VOLUME_FUNCTION));
+
+        assertEquals(result, Constants.HANDLED);
+        verify(mAudioManager, times(1))
+                .adjustStreamVolume(anyInt(), eq(AudioManager.ADJUST_UNMUTE), anyInt());
+    }
+
     @Test
     public void handleVendorCommand_notHandled() {
         HdmiCecMessage vendorCommand = HdmiCecMessageBuilder.buildVendorCommand(ADDR_TV,