Add display committed state to DisplayInfo

This adds the committed state to the display.
The `state` is used to set the correct power state (e.g. turning display on/off), however there was no way to know when this power state change finished. This new "committedState" aims to fulfill this gap.

DisplayListeners receives a `onDisplayChanged` callback whenever the power state change is fully committed, and can get this information from DisplayInfo.

This will be used in a follow up cl to improve unfold latency performances.

Bug: 223808403
Bug: 220690092
Bug: 197515205
Test: atest LocalDisplayAdapterTest && manual
Change-Id: Ia2fbab768b696c59578d974c88157ee3c8f3ddde

core/java/android/hardware/display/DisplayManagerGlobal.java

@@ -41,6 +41,7 @@ import android.os.Looper;
 import android.os.Message;
 import android.os.RemoteException;
 import android.os.ServiceManager;
+import android.os.Trace;
 import android.util.Log;
 import android.util.Pair;
 import android.util.SparseArray;
@@ -987,7 +988,8 @@ public final class DisplayManagerGlobal {
         @Override
         public void onDisplayEvent(int displayId, @DisplayEvent int event) {
             if (DEBUG) {
-                Log.d(TAG, "onDisplayEvent: displayId=" + displayId + ", event=" + event);
+                Log.d(TAG, "onDisplayEvent: displayId=" + displayId + ", event=" + eventToString(
+                        event));
             }
             handleDisplayEvent(displayId, event);
         }
@@ -1021,6 +1023,12 @@ public final class DisplayManagerGlobal {
 
         @Override
         public void handleMessage(Message msg) {
+            if (DEBUG) {
+                Trace.beginSection(
+                        "DisplayListenerDelegate(" + eventToString(msg.what)
+                                + ", display=" + msg.arg1
+                                + ", listener=" + mListener.getClass() + ")");
+            }
             switch (msg.what) {
                 case EVENT_DISPLAY_ADDED:
                     if ((mEventsMask & DisplayManager.EVENT_FLAG_DISPLAY_ADDED) != 0) {
@@ -1047,6 +1055,9 @@ public final class DisplayManagerGlobal {
                     }
                     break;
             }
+            if (DEBUG) {
+                Trace.endSection();
+            }
         }
     }
 
@@ -1150,4 +1161,18 @@ public final class DisplayManagerGlobal {
             updateCallbackIfNeededLocked();
         }
     }
+
+    private static String eventToString(@DisplayEvent int event) {
+        switch (event) {
+            case EVENT_DISPLAY_ADDED:
+                return "ADDED";
+            case EVENT_DISPLAY_CHANGED:
+                return "CHANGED";
+            case EVENT_DISPLAY_REMOVED:
+                return "REMOVED";
+            case EVENT_DISPLAY_BRIGHTNESS_CHANGED:
+                return "BRIGHTNESS_CHANGED";
+        }
+        return "UNKNOWN";
+    }
 }

core/java/android/view/Display.java

@@ -1615,6 +1615,21 @@ public final class Display {
         }
     }
 
+    /**
+     * Returns the committed state of the display.
+     *
+     * @return The latest committed display state, such as {@link #STATE_ON}. The display state
+     * {@link Display#getState()} is set as committed only after power state changes finish.
+     *
+     * @hide
+     */
+    public int getCommittedState() {
+        synchronized (mLock) {
+            updateDisplayInfoLocked();
+            return mIsValid ? mDisplayInfo.committedState : STATE_UNKNOWN;
+        }
+    }
+
     /**
      * Returns true if the specified UID has access to this display.
      * @hide

core/java/android/view/DisplayInfo.java

@@ -252,6 +252,12 @@ public final class DisplayInfo implements Parcelable {
      */
     public int state;
 
+    /**
+     * The current committed state of the display. For example, this becomes
+     * {@link android.view.Display#STATE_ON} only after the power state ON is fully committed.
+     */
+    public int committedState;
+
     /**
      * The UID of the application that owns this display, or zero if it is owned by the system.
      * <p>
@@ -387,6 +393,7 @@ public final class DisplayInfo implements Parcelable {
                 && appVsyncOffsetNanos == other.appVsyncOffsetNanos
                 && presentationDeadlineNanos == other.presentationDeadlineNanos
                 && state == other.state
+                && committedState == other.committedState
                 && ownerUid == other.ownerUid
                 && Objects.equals(ownerPackageName, other.ownerPackageName)
                 && removeMode == other.removeMode
@@ -439,6 +446,7 @@ public final class DisplayInfo implements Parcelable {
         appVsyncOffsetNanos = other.appVsyncOffsetNanos;
         presentationDeadlineNanos = other.presentationDeadlineNanos;
         state = other.state;
+        committedState = other.committedState;
         ownerUid = other.ownerUid;
         ownerPackageName = other.ownerPackageName;
         removeMode = other.removeMode;
@@ -491,6 +499,7 @@ public final class DisplayInfo implements Parcelable {
         appVsyncOffsetNanos = source.readLong();
         presentationDeadlineNanos = source.readLong();
         state = source.readInt();
+        committedState = source.readInt();
         ownerUid = source.readInt();
         ownerPackageName = source.readString8();
         uniqueId = source.readString8();
@@ -548,6 +557,7 @@ public final class DisplayInfo implements Parcelable {
         dest.writeLong(appVsyncOffsetNanos);
         dest.writeLong(presentationDeadlineNanos);
         dest.writeInt(state);
+        dest.writeInt(committedState);
         dest.writeInt(ownerUid);
         dest.writeString8(ownerPackageName);
         dest.writeString8(uniqueId);
@@ -772,6 +782,8 @@ public final class DisplayInfo implements Parcelable {
         sb.append(rotation);
         sb.append(", state ");
         sb.append(Display.stateToString(state));
+        sb.append(", committedState ");
+        sb.append(Display.stateToString(committedState));
 
         if (Process.myUid() != Process.SYSTEM_UID) {
             sb.append("}");

services/core/java/com/android/server/display/DisplayDeviceInfo.java

@@ -173,7 +173,7 @@ final class DisplayDeviceInfo {
     public static final int TOUCH_VIRTUAL = 3;
 
     /**
-     * Diff result: The {@link #state} fields differ.
+     * Diff result: The {@link #state} or {@link #committedState} fields differ.
      */
     public static final int DIFF_STATE = 1 << 0;
 
@@ -334,6 +334,13 @@ final class DisplayDeviceInfo {
      */
     public int state = Display.STATE_ON;
 
+    /**
+     * Display committed state.
+     *
+     * This matches {@link DisplayDeviceInfo#state} only after the power state change finishes.
+     */
+    public int committedState = Display.STATE_UNKNOWN;
+
     /**
      * The UID of the application that owns this display, or zero if it is owned by the system.
      * <p>
@@ -387,7 +394,7 @@ final class DisplayDeviceInfo {
      */
     public int diff(DisplayDeviceInfo other) {
         int diff = 0;
-        if (state != other.state) {
+        if (state != other.state || committedState != other.committedState) {
             diff |= DIFF_STATE;
         }
         if (colorMode != other.colorMode) {
@@ -461,6 +468,7 @@ final class DisplayDeviceInfo {
         address = other.address;
         deviceProductInfo = other.deviceProductInfo;
         state = other.state;
+        committedState = other.committedState;
         ownerUid = other.ownerUid;
         ownerPackageName = other.ownerPackageName;
         frameRateOverrides = other.frameRateOverrides;
@@ -501,6 +509,7 @@ final class DisplayDeviceInfo {
         }
         sb.append(", deviceProductInfo ").append(deviceProductInfo);
         sb.append(", state ").append(Display.stateToString(state));
+        sb.append(", committedState ").append(Display.stateToString(committedState));
         if (ownerUid != 0 || ownerPackageName != null) {
             sb.append(", owner ").append(ownerPackageName);
             sb.append(" (uid ").append(ownerUid).append(")");

services/core/java/com/android/server/display/LocalDisplayAdapter.java

@@ -191,6 +191,8 @@ final class LocalDisplayAdapter extends DisplayAdapter {
         private DisplayDeviceInfo mInfo;
         private boolean mHavePendingChanges;
         private int mState = Display.STATE_UNKNOWN;
+        private int mCommittedState = Display.STATE_UNKNOWN;
+
         // This is only set in the runnable returned from requestDisplayStateLocked.
         private float mBrightnessState = PowerManager.BRIGHTNESS_INVALID_FLOAT;
         private float mSdrBrightnessState = PowerManager.BRIGHTNESS_INVALID_FLOAT;
@@ -632,6 +634,7 @@ final class LocalDisplayAdapter extends DisplayAdapter {
                 mInfo.appVsyncOffsetNanos = mActiveSfDisplayMode.appVsyncOffsetNanos;
                 mInfo.presentationDeadlineNanos = mActiveSfDisplayMode.presentationDeadlineNanos;
                 mInfo.state = mState;
+                mInfo.committedState = mCommittedState;
                 mInfo.uniqueId = getUniqueId();
                 final DisplayAddress.Physical physicalAddress =
                         DisplayAddress.fromPhysicalDisplayId(mPhysicalDisplayId);
@@ -812,6 +815,7 @@ final class LocalDisplayAdapter extends DisplayAdapter {
                         } finally {
                             Trace.traceEnd(Trace.TRACE_TAG_POWER);
                         }
+                        setCommittedState(state);
                         // If we're entering a suspended (but not OFF) power state and we
                         // have a sidekick available, tell it now that it can take control.
                         if (Display.isSuspendedState(state) && state != Display.STATE_OFF
@@ -826,6 +830,16 @@ final class LocalDisplayAdapter extends DisplayAdapter {
                         }
                     }
 
+                    private void setCommittedState(int state) {
+                        // After the display state is set, let's update the committed state.
+                        getHandler().post(() -> {
+                            synchronized (getSyncRoot()) {
+                                mCommittedState = state;
+                                updateDeviceInfoLocked();
+                            }
+                        });
+                    }
+
                     private void setDisplayBrightness(float brightnessState,
                             float sdrBrightnessState) {
                         // brightnessState includes invalid, off and full range.
@@ -1091,6 +1105,7 @@ final class LocalDisplayAdapter extends DisplayAdapter {
             pw.println("mDefaultModeId=" + mDefaultModeId);
             pw.println("mUserPreferredModeId=" + mUserPreferredModeId);
             pw.println("mState=" + Display.stateToString(mState));
+            pw.println("mCommittedState=" + Display.stateToString(mCommittedState));
             pw.println("mBrightnessState=" + mBrightnessState);
             pw.println("mBacklightAdapter=" + mBacklightAdapter);
             pw.println("mAllmSupported=" + mAllmSupported);

services/core/java/com/android/server/display/LogicalDisplay.java

@@ -413,6 +413,7 @@ final class LogicalDisplay {
             mBaseDisplayInfo.appVsyncOffsetNanos = deviceInfo.appVsyncOffsetNanos;
             mBaseDisplayInfo.presentationDeadlineNanos = deviceInfo.presentationDeadlineNanos;
             mBaseDisplayInfo.state = deviceInfo.state;
+            mBaseDisplayInfo.committedState = deviceInfo.committedState;
             mBaseDisplayInfo.smallestNominalAppWidth = maskedWidth;
             mBaseDisplayInfo.smallestNominalAppHeight = maskedHeight;
             mBaseDisplayInfo.largestNominalAppWidth = maskedWidth;

services/tests/mockingservicestests/src/com/android/server/display/LocalDisplayAdapterTest.java

@@ -556,6 +556,40 @@ public class LocalDisplayAdapterTest {
         assertThat(displayDeviceInfo.allmSupported).isFalse();
     }
 
+    @Test
+    public void testAfterDisplayStateChanges_committedSetAfterState() throws Exception {
+        FakeDisplay display = new FakeDisplay(PORT_A);
+        setUpDisplay(display);
+        updateAvailableDisplays();
+        mAdapter.registerLocked();
+        waitForHandlerToComplete(mHandler, HANDLER_WAIT_MS);
+        assertThat(mListener.addedDisplays.size()).isEqualTo(1);
+        DisplayDevice displayDevice = mListener.addedDisplays.get(0);
+
+        // Turn off.
+        Runnable changeStateRunnable = displayDevice.requestDisplayStateLocked(Display.STATE_OFF, 0,
+                0);
+        waitForHandlerToComplete(mHandler, HANDLER_WAIT_MS);
+        assertThat(mListener.changedDisplays.size()).isEqualTo(1);
+        mListener.changedDisplays.clear();
+        assertThat(displayDevice.getDisplayDeviceInfoLocked().state).isEqualTo(Display.STATE_OFF);
+        assertThat(displayDevice.getDisplayDeviceInfoLocked().committedState).isNotEqualTo(
+                Display.STATE_OFF);
+        verify(mSurfaceControlProxy, never()).setDisplayPowerMode(display.token, Display.STATE_OFF);
+
+        // Execute powerstate change.
+        changeStateRunnable.run();
+        waitForHandlerToComplete(mHandler, HANDLER_WAIT_MS);
+
+
+        // Verify that committed triggered a new change event and is set correctly.
+        verify(mSurfaceControlProxy, never()).setDisplayPowerMode(display.token, Display.STATE_OFF);
+        assertThat(mListener.changedDisplays.size()).isEqualTo(1);
+        assertThat(displayDevice.getDisplayDeviceInfoLocked().state).isEqualTo(Display.STATE_OFF);
+        assertThat(displayDevice.getDisplayDeviceInfoLocked().committedState).isEqualTo(
+                Display.STATE_OFF);
+    }
+
     @Test
     public void testAfterDisplayChange_GameContentTypeSupportIsUpdated() throws Exception {
         FakeDisplay display = new FakeDisplay(PORT_A);