Merge "Allow rotation when display is half-folded" into tm-qpr-dev

10 files changed, 470 insertions, 35 deletions

diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 3408f75f0f72..84280605862f 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -658,6 +658,20 @@
         -->
     </integer-array>
 
+    <!-- The device states (supplied by DeviceStateManager) that should be treated as half-folded by
+     the display fold controller. Default is empty. -->
+    <integer-array name="config_halfFoldedDeviceStates">
+        <!-- Example:
+        <item>0</item>
+        <item>1</item>
+        <item>2</item>
+        -->
+    </integer-array>
+
+    <!-- Indicates whether the window manager reacts to half-fold device states by overriding
+     rotation. -->
+    <bool name="config_windowManagerHalfFoldAutoRotateOverride">false</bool>
+
     <!-- When a device enters any of these states, it should be woken up. States are defined in
          device_state_configuration.xml. -->
     <integer-array name="config_deviceStatesOnWhichToWakeUp">
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index 16798b8b0a24..97105d80bf79 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -4005,6 +4005,8 @@
 
   <!-- For Foldables -->
   <java-symbol type="array" name="config_foldedDeviceStates" />
+  <java-symbol type="array" name="config_halfFoldedDeviceStates" />
+  <java-symbol type="bool" name="config_windowManagerHalfFoldAutoRotateOverride" />
   <java-symbol type="array" name="config_deviceStatesOnWhichToWakeUp" />
   <java-symbol type="array" name="config_deviceStatesOnWhichToSleep" />
   <java-symbol type="string" name="config_foldedArea" />
diff --git a/data/etc/services.core.protolog.json b/data/etc/services.core.protolog.json
index b1ecb43f9a23..31e2abe0bb85 100644
--- a/data/etc/services.core.protolog.json
+++ b/data/etc/services.core.protolog.json
@@ -1087,6 +1087,12 @@
       "group": "WM_DEBUG_FOCUS",
       "at": "com\/android\/server\/wm\/WindowState.java"
     },
+    "-1043981272": {
+      "message": "Reverting orientation. Rotating to %s from %s rather than %s.",
+      "level": "VERBOSE",
+      "group": "WM_DEBUG_ORIENTATION",
+      "at": "com\/android\/server\/wm\/DisplayRotation.java"
+    },
     "-1042574499": {
       "message": "Attempted to add Accessibility overlay window with unknown token %s.  Aborting.",
       "level": "WARN",
@@ -4285,6 +4291,12 @@
       "group": "WM_ERROR",
       "at": "com\/android\/server\/wm\/WindowManagerService.java"
     },
+    "2066210760": {
+      "message": "foldStateChanged: displayId %d, halfFoldStateChanged %s, saved rotation: %d, mUserRotation: %d, mLastSensorRotation: %d, mLastOrientation: %d, mRotation: %d",
+      "level": "VERBOSE",
+      "group": "WM_DEBUG_ORIENTATION",
+      "at": "com\/android\/server\/wm\/DisplayRotation.java"
+    },
     "2070726247": {
       "message": "InsetsSource updateVisibility for %s, serverVisible: %s clientVisible: %s",
       "level": "DEBUG",
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java b/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
index 22bffda33918..6087655615a6 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/rotation/RotationButtonController.java
@@ -132,8 +132,11 @@ public class RotationButtonController {
             mMainThreadHandler.postAtFrontOfQueue(() -> {
                 // If the screen rotation changes while locked, potentially update lock to flow with
                 // new screen rotation and hide any showing suggestions.
-                if (isRotationLocked()) {
-                    if (shouldOverrideUserLockPrefs(rotation)) {
+                boolean rotationLocked = isRotationLocked();
+                // The isVisible check makes the rotation button disappear when we are not locked
+                // (e.g. for tabletop auto-rotate).
+                if (rotationLocked || mRotationButton.isVisible()) {
+                    if (shouldOverrideUserLockPrefs(rotation) && rotationLocked) {
                         setRotationLockedAtAngle(rotation);
                     }
                     setRotateSuggestionButtonState(false /* visible */, true /* forced */);
diff --git a/services/core/java/com/android/server/wm/DeviceStateController.java b/services/core/java/com/android/server/wm/DeviceStateController.java
new file mode 100644
index 000000000000..a6f855755192
--- /dev/null
+++ b/services/core/java/com/android/server/wm/DeviceStateController.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wm;
+
+import android.annotation.Nullable;
+import android.content.Context;
+import android.hardware.devicestate.DeviceStateManager;
+import android.os.Handler;
+import android.os.HandlerExecutor;
+
+import com.android.internal.util.ArrayUtils;
+
+import java.util.function.Consumer;
+
+/**
+ * Class that registers callbacks with the {@link DeviceStateManager} and
+ * responds to fold state changes by forwarding such events to a delegate.
+ */
+final class DeviceStateController {
+    private final DeviceStateManager mDeviceStateManager;
+    private final Context mContext;
+
+    private FoldStateListener mDeviceStateListener;
+
+    public enum FoldState {
+        UNKNOWN, OPEN, FOLDED, HALF_FOLDED
+    }
+
+    DeviceStateController(Context context, Handler handler, Consumer<FoldState> delegate) {
+        mContext = context;
+        mDeviceStateManager = mContext.getSystemService(DeviceStateManager.class);
+        if (mDeviceStateManager != null) {
+            mDeviceStateListener = new FoldStateListener(mContext, delegate);
+            mDeviceStateManager
+                    .registerCallback(new HandlerExecutor(handler),
+                            mDeviceStateListener);
+        }
+    }
+
+    void unregisterFromDeviceStateManager() {
+        if (mDeviceStateListener != null) {
+            mDeviceStateManager.unregisterCallback(mDeviceStateListener);
+        }
+    }
+
+    /**
+     * A listener for half-fold device state events that dispatches state changes to a delegate.
+     */
+    static final class FoldStateListener implements DeviceStateManager.DeviceStateCallback {
+
+        private final int[] mHalfFoldedDeviceStates;
+        private final int[] mFoldedDeviceStates;
+
+        @Nullable
+        private FoldState mLastResult;
+        private final Consumer<FoldState> mDelegate;
+
+        FoldStateListener(Context context, Consumer<FoldState> delegate) {
+            mFoldedDeviceStates = context.getResources().getIntArray(
+                    com.android.internal.R.array.config_foldedDeviceStates);
+            mHalfFoldedDeviceStates = context.getResources().getIntArray(
+                    com.android.internal.R.array.config_halfFoldedDeviceStates);
+            mDelegate = delegate;
+        }
+
+        @Override
+        public void onStateChanged(int state) {
+            final boolean halfFolded = ArrayUtils.contains(mHalfFoldedDeviceStates, state);
+            FoldState result;
+            if (halfFolded) {
+                result = FoldState.HALF_FOLDED;
+            } else {
+                final boolean folded = ArrayUtils.contains(mFoldedDeviceStates, state);
+                result = folded ? FoldState.FOLDED : FoldState.OPEN;
+            }
+            if (mLastResult == null || !mLastResult.equals(result)) {
+                mLastResult = result;
+                mDelegate.accept(result);
+            }
+        }
+    }
+}
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 71c80fb9a97c..38f6a53982c4 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -564,6 +564,7 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
     final FixedRotationTransitionListener mFixedRotationTransitionListener =
             new FixedRotationTransitionListener();
 
+    private final DeviceStateController mDeviceStateController;
     private final PhysicalDisplaySwitchTransitionLauncher mDisplaySwitchTransitionLauncher;
     final RemoteDisplayChangeController mRemoteDisplayChangeController;
 
@@ -1119,6 +1120,13 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
 
         mDisplayPolicy = new DisplayPolicy(mWmService, this);
         mDisplayRotation = new DisplayRotation(mWmService, this);
+
+        mDeviceStateController = new DeviceStateController(mWmService.mContext, mWmService.mH,
+                newFoldState -> {
+                    mDisplaySwitchTransitionLauncher.foldStateChanged(newFoldState);
+                    mDisplayRotation.foldStateChanged(newFoldState);
+                });
+
         mCloseToSquareMaxAspectRatio = mWmService.mContext.getResources().getFloat(
                 R.dimen.config_closeToSquareDisplayMaxAspectRatio);
         if (isDefaultDisplay) {
@@ -3218,7 +3226,7 @@ class DisplayContent extends RootDisplayArea implements WindowManagerPolicy.Disp
             mTransitionController.unregisterLegacyListener(mFixedRotationTransitionListener);
             handleAnimatingStoppedAndTransition();
             mWmService.stopFreezingDisplayLocked();
-            mDisplaySwitchTransitionLauncher.destroy();
+            mDeviceStateController.unregisterFromDeviceStateManager();
             super.removeImmediately();
             if (DEBUG_DISPLAY) Slog.v(TAG_WM, "Removing display=" + this);
             mPointerEventDispatcher.dispose();
diff --git a/services/core/java/com/android/server/wm/DisplayRotation.java b/services/core/java/com/android/server/wm/DisplayRotation.java
index 97609a7dd8ba..a8d13c57ffa2 100644
--- a/services/core/java/com/android/server/wm/DisplayRotation.java
+++ b/services/core/java/com/android/server/wm/DisplayRotation.java
@@ -40,6 +40,7 @@ import static com.android.server.wm.WindowManagerService.WINDOW_FREEZE_TIMEOUT_D
 
 import android.annotation.AnimRes;
 import android.annotation.IntDef;
+import android.annotation.Nullable;
 import android.app.ActivityManager;
 import android.content.ContentResolver;
 import android.content.Context;
@@ -108,6 +109,8 @@ public class DisplayRotation {
     private OrientationListener mOrientationListener;
     private StatusBarManagerInternal mStatusBarManagerInternal;
     private SettingsObserver mSettingsObserver;
+    @Nullable
+    private FoldController mFoldController;
 
     @ScreenOrientation
     private int mCurrentAppOrientation = SCREEN_ORIENTATION_UNSPECIFIED;
@@ -238,6 +241,10 @@ public class DisplayRotation {
             mOrientationListener.setCurrentRotation(mRotation);
             mSettingsObserver = new SettingsObserver(uiHandler);
             mSettingsObserver.observe();
+            if (mSupportAutoRotation && mContext.getResources().getBoolean(
+                    R.bool.config_windowManagerHalfFoldAutoRotateOverride)) {
+                mFoldController = new FoldController();
+            }
         }
     }
 
@@ -436,7 +443,17 @@ public class DisplayRotation {
 
         final int oldRotation = mRotation;
         final int lastOrientation = mLastOrientation;
-        final int rotation = rotationForOrientation(lastOrientation, oldRotation);
+        int rotation = rotationForOrientation(lastOrientation, oldRotation);
+        // Use the saved rotation for tabletop mode, if set.
+        if (mFoldController != null && mFoldController.shouldRevertOverriddenRotation()) {
+            int prevRotation = rotation;
+            rotation = mFoldController.revertOverriddenRotation();
+            ProtoLog.v(WM_DEBUG_ORIENTATION,
+                    "Reverting orientation. Rotating to %s from %s rather than %s.",
+                    Surface.rotationToString(rotation),
+                    Surface.rotationToString(oldRotation),
+                    Surface.rotationToString(prevRotation));
+        }
         ProtoLog.v(WM_DEBUG_ORIENTATION,
                 "Computed rotation=%s (%d) for display id=%d based on lastOrientation=%s (%d) and "
                         + "oldRotation=%s (%d)",
@@ -1138,7 +1155,8 @@ public class DisplayRotation {
             // If we don't support auto-rotation then bail out here and ignore
             // the sensor and any rotation lock settings.
             preferredRotation = -1;
-        } else if ((mUserRotationMode == WindowManagerPolicy.USER_ROTATION_FREE
+        } else if (((mUserRotationMode == WindowManagerPolicy.USER_ROTATION_FREE
+                            || isTabletopAutoRotateOverrideEnabled())
                         && (orientation == ActivityInfo.SCREEN_ORIENTATION_USER
                                 || orientation == ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED
                                 || orientation == ActivityInfo.SCREEN_ORIENTATION_USER_LANDSCAPE
@@ -1292,10 +1310,17 @@ public class DisplayRotation {
         return false;
     }
 
+    private boolean isTabletopAutoRotateOverrideEnabled() {
+        return mFoldController != null && mFoldController.overrideFrozenRotation();
+    }
+
     private boolean isRotationChoicePossible(int orientation) {
         // Rotation choice is only shown when the user is in locked mode.
         if (mUserRotationMode != WindowManagerPolicy.USER_ROTATION_LOCKED) return false;
 
+        // Don't show rotation choice if we are in tabletop or book modes.
+        if (isTabletopAutoRotateOverrideEnabled()) return false;
+
         // We should only enable rotation choice if the rotation isn't forced by the lid, dock,
         // demo, hdmi, vr, etc mode.
 
@@ -1496,6 +1521,74 @@ public class DisplayRotation {
         proto.end(token);
     }
 
+    /**
+     * Called by the DeviceStateManager callback when the device state changes.
+     */
+    void foldStateChanged(DeviceStateController.FoldState foldState) {
+        if (mFoldController != null) {
+            synchronized (mLock) {
+                mFoldController.foldStateChanged(foldState);
+            }
+        }
+    }
+
+    private class FoldController {
+        @Surface.Rotation
+        private int mHalfFoldSavedRotation = -1; // No saved rotation
+        private DeviceStateController.FoldState mFoldState =
+                DeviceStateController.FoldState.UNKNOWN;
+
+        boolean overrideFrozenRotation() {
+            return mFoldState == DeviceStateController.FoldState.HALF_FOLDED;
+        }
+
+        boolean shouldRevertOverriddenRotation() {
+            return mFoldState == DeviceStateController.FoldState.OPEN // When transitioning to open.
+                    && mHalfFoldSavedRotation != -1 // Ignore if we've already reverted.
+                    && mUserRotationMode
+                    == WindowManagerPolicy.USER_ROTATION_LOCKED; // Ignore if we're unlocked.
+        }
+
+        int revertOverriddenRotation() {
+            int savedRotation = mHalfFoldSavedRotation;
+            mHalfFoldSavedRotation = -1;
+            return savedRotation;
+        }
+
+        void foldStateChanged(DeviceStateController.FoldState newState) {
+            ProtoLog.v(WM_DEBUG_ORIENTATION,
+                    "foldStateChanged: displayId %d, halfFoldStateChanged %s, "
+                    + "saved rotation: %d, mUserRotation: %d, mLastSensorRotation: %d, "
+                    + "mLastOrientation: %d, mRotation: %d",
+                    mDisplayContent.getDisplayId(), newState.name(), mHalfFoldSavedRotation,
+                    mUserRotation, mLastSensorRotation, mLastOrientation, mRotation);
+            if (mFoldState == DeviceStateController.FoldState.UNKNOWN) {
+                mFoldState = newState;
+                return;
+            }
+            if (newState == DeviceStateController.FoldState.HALF_FOLDED
+                    && mFoldState != DeviceStateController.FoldState.HALF_FOLDED) {
+                // The device has transitioned to HALF_FOLDED state: save the current rotation and
+                // update the device rotation.
+                mHalfFoldSavedRotation = mRotation;
+                mFoldState = newState;
+                // Now mFoldState is set to HALF_FOLDED, the overrideFrozenRotation function will
+                // return true, so rotation is unlocked.
+                mService.updateRotation(false /* alwaysSendConfiguration */,
+                        false /* forceRelayout */);
+            } else {
+                // Revert the rotation to our saved value if we transition from HALF_FOLDED.
+                mRotation = mHalfFoldSavedRotation;
+                // Tell the device to update its orientation (mFoldState is still HALF_FOLDED here
+                // so we will override USER_ROTATION_LOCKED and allow a rotation).
+                mService.updateRotation(false /* alwaysSendConfiguration */,
+                        false /* forceRelayout */);
+                // Once we are rotated, set mFoldstate, effectively removing the lock override.
+                mFoldState = newState;
+            }
+        }
+    }
+
     private class OrientationListener extends WindowOrientationListener implements Runnable {
         transient boolean mEnabled;
 
diff --git a/services/core/java/com/android/server/wm/PhysicalDisplaySwitchTransitionLauncher.java b/services/core/java/com/android/server/wm/PhysicalDisplaySwitchTransitionLauncher.java
index a89894db4b4b..30bdc3477edf 100644
--- a/services/core/java/com/android/server/wm/PhysicalDisplaySwitchTransitionLauncher.java
+++ b/services/core/java/com/android/server/wm/PhysicalDisplaySwitchTransitionLauncher.java
@@ -24,10 +24,7 @@ import static com.android.server.wm.ActivityTaskManagerService.POWER_MODE_REASON
 import android.animation.ValueAnimator;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.content.Context;
 import android.graphics.Rect;
-import android.hardware.devicestate.DeviceStateManager;
-import android.os.HandlerExecutor;
 import android.window.DisplayAreaInfo;
 import android.window.TransitionRequestInfo;
 import android.window.WindowContainerTransaction;
@@ -36,11 +33,8 @@ public class PhysicalDisplaySwitchTransitionLauncher {
 
     private final DisplayContent mDisplayContent;
     private final WindowManagerService mService;
-    private final DeviceStateManager mDeviceStateManager;
     private final TransitionController mTransitionController;
 
-    private DeviceStateListener mDeviceStateListener;
-
     /**
      * If on a foldable device represents whether the device is folded or not
      */
@@ -52,21 +46,15 @@ public class PhysicalDisplaySwitchTransitionLauncher {
         mDisplayContent = displayContent;
         mService = displayContent.mWmService;
         mTransitionController = transitionController;
-
-        mDeviceStateManager = mService.mContext.getSystemService(DeviceStateManager.class);
-
-        if (mDeviceStateManager != null) {
-            mDeviceStateListener = new DeviceStateListener(mService.mContext);
-            mDeviceStateManager
-                    .registerCallback(new HandlerExecutor(mDisplayContent.mWmService.mH),
-                            mDeviceStateListener);
-        }
     }
 
-    public void destroy() {
-        if (mDeviceStateManager != null) {
-            mDeviceStateManager.unregisterCallback(mDeviceStateListener);
-        }
+    /**
+     *   Called by the DeviceStateManager callback when the state changes.
+     */
+    void foldStateChanged(DeviceStateController.FoldState newFoldState) {
+        // Ignore transitions to/from half-folded.
+        if (newFoldState == DeviceStateController.FoldState.HALF_FOLDED) return;
+        mIsFolded = newFoldState == DeviceStateController.FoldState.FOLDED;
     }
 
     /**
@@ -143,10 +131,4 @@ public class PhysicalDisplaySwitchTransitionLauncher {
         mTransition = null;
     }
 
-    class DeviceStateListener extends DeviceStateManager.FoldStateListener {
-
-        DeviceStateListener(Context context) {
-            super(context, newIsFolded -> mIsFolded = newIsFolded);
-        }
-    }
 }
diff --git a/services/tests/wmtests/src/com/android/server/wm/DeviceStateControllerTests.java b/services/tests/wmtests/src/com/android/server/wm/DeviceStateControllerTests.java
new file mode 100644
index 000000000000..86732c9a3f46
--- /dev/null
+++ b/services/tests/wmtests/src/com/android/server/wm/DeviceStateControllerTests.java
@@ -0,0 +1,176 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.wm;
+
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.any;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.mock;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.times;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.verify;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.when;
+
+import static org.junit.Assert.assertEquals;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.hardware.devicestate.DeviceStateManager;
+import android.os.Handler;
+import android.platform.test.annotations.Presubmit;
+
+import androidx.test.filters.SmallTest;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.ArgumentCaptor;
+
+import java.util.function.Consumer;
+
+/**
+ * Test class for {@link DeviceStateController}.
+ *
+ * Build/Install/Run:
+ *  atest WmTests:DeviceStateControllerTests
+ */
+@SmallTest
+@Presubmit
+public class DeviceStateControllerTests {
+
+    private DeviceStateController.FoldStateListener mFoldStateListener;
+    private DeviceStateController mTarget;
+    private DeviceStateControllerBuilder mBuilder;
+
+    private Context mMockContext;
+    private Handler mMockHandler;
+    private Resources mMockRes;
+    private DeviceStateManager mMockDeviceStateManager;
+
+    private Consumer<DeviceStateController.FoldState> mDelegate;
+    private DeviceStateController.FoldState mCurrentState = DeviceStateController.FoldState.UNKNOWN;
+
+    @Before
+    public void setUp() {
+        mBuilder = new DeviceStateControllerBuilder();
+        mCurrentState = DeviceStateController.FoldState.UNKNOWN;
+    }
+
+    private void initialize(boolean supportFold, boolean supportHalfFold) throws Exception {
+        mBuilder.setSupportFold(supportFold, supportHalfFold);
+        mDelegate = (newFoldState) -> {
+            mCurrentState = newFoldState;
+        };
+        mBuilder.setDelegate(mDelegate);
+        mBuilder.build();
+        verifyFoldStateListenerRegistration(1);
+    }
+
+    @Test
+    public void testInitialization() throws Exception {
+        initialize(true /* supportFold */, true /* supportHalfFolded */);
+        mFoldStateListener.onStateChanged(mUnfoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.OPEN);
+    }
+
+    @Test
+    public void testInitializationWithNoFoldSupport() throws Exception {
+        initialize(false /* supportFold */, false /* supportHalfFolded */);
+        mFoldStateListener.onStateChanged(mFoldedStates[0]);
+        // Note that the folded state is ignored.
+        assertEquals(mCurrentState, DeviceStateController.FoldState.OPEN);
+    }
+
+    @Test
+    public void testWithFoldSupported() throws Exception {
+        initialize(true /* supportFold */, false /* supportHalfFolded */);
+        mFoldStateListener.onStateChanged(mUnfoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.OPEN);
+        mFoldStateListener.onStateChanged(mFoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.FOLDED);
+        mFoldStateListener.onStateChanged(mHalfFoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.OPEN); // Ignored
+    }
+
+    @Test
+    public void testWithHalfFoldSupported() throws Exception {
+        initialize(true /* supportFold */, true /* supportHalfFolded */);
+        mFoldStateListener.onStateChanged(mUnfoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.OPEN);
+        mFoldStateListener.onStateChanged(mFoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.FOLDED);
+        mFoldStateListener.onStateChanged(mHalfFoldedStates[0]);
+        assertEquals(mCurrentState, DeviceStateController.FoldState.HALF_FOLDED);
+    }
+
+
+    private final int[] mFoldedStates = {0};
+    private final int[] mUnfoldedStates = {1};
+    private final int[] mHalfFoldedStates = {2};
+
+
+    private void verifyFoldStateListenerRegistration(int numOfInvocation) {
+        final ArgumentCaptor<DeviceStateController.FoldStateListener> listenerCaptor =
+                ArgumentCaptor.forClass(DeviceStateController.FoldStateListener.class);
+        verify(mMockDeviceStateManager, times(numOfInvocation)).registerCallback(
+                any(),
+                listenerCaptor.capture());
+        if (numOfInvocation > 0) {
+            mFoldStateListener = listenerCaptor.getValue();
+        }
+    }
+
+    private class DeviceStateControllerBuilder {
+        private boolean mSupportFold = false;
+        private boolean mSupportHalfFold = false;
+        private Consumer<DeviceStateController.FoldState> mDelegate;
+
+        DeviceStateControllerBuilder setSupportFold(
+                boolean supportFold, boolean supportHalfFold) {
+            mSupportFold = supportFold;
+            mSupportHalfFold = supportHalfFold;
+            return this;
+        }
+
+        DeviceStateControllerBuilder setDelegate(
+                Consumer<DeviceStateController.FoldState> delegate) {
+            mDelegate = delegate;
+            return this;
+        }
+
+        private void mockFold(boolean enableFold, boolean enableHalfFold) {
+            if (enableFold) {
+                when(mMockContext.getResources().getIntArray(
+                        com.android.internal.R.array.config_foldedDeviceStates))
+                        .thenReturn(mFoldedStates);
+            }
+            if (enableHalfFold) {
+                when(mMockContext.getResources().getIntArray(
+                        com.android.internal.R.array.config_halfFoldedDeviceStates))
+                        .thenReturn(mHalfFoldedStates);
+            }
+        }
+
+        private void build() throws Exception {
+            mMockContext = mock(Context.class);
+            mMockRes = mock(Resources.class);
+            when(mMockContext.getResources()).thenReturn((mMockRes));
+            mMockDeviceStateManager = mock(DeviceStateManager.class);
+            when(mMockContext.getSystemService(DeviceStateManager.class))
+                    .thenReturn(mMockDeviceStateManager);
+            mockFold(mSupportFold, mSupportHalfFold);
+            mMockHandler = mock(Handler.class);
+            mTarget = new DeviceStateController(mMockContext, mMockHandler, mDelegate);
+        }
+    }
+}
diff --git a/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
index 89f71110f3c2..b45c37f9da0c 100644
--- a/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/DisplayRotationTests.java
@@ -28,6 +28,7 @@ import static android.view.IWindowManager.FIXED_TO_USER_ROTATION_ENABLED;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.any;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.anyBoolean;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.anyInt;
+import static com.android.dx.mockito.inline.extended.ExtendedMockito.atLeast;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.atMost;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.eq;
@@ -103,7 +104,7 @@ public class DisplayRotationTests {
     private Context mMockContext;
     private Resources mMockRes;
     private SensorManager mMockSensorManager;
-    private Sensor mFakeSensor;
+    private Sensor mFakeOrientationSensor;
     private DisplayWindowSettings mMockDisplayWindowSettings;
     private ContentResolver mMockResolver;
     private FakeSettingsProvider mFakeSettingsProvider;
@@ -323,7 +324,7 @@ public class DisplayRotationTests {
         waitForUiHandler();
         verify(mMockSensorManager, times(numOfInvocation)).registerListener(
                 listenerCaptor.capture(),
-                same(mFakeSensor),
+                same(mFakeOrientationSensor),
                 anyInt(),
                 any());
         if (numOfInvocation > 0) {
@@ -460,7 +461,7 @@ public class DisplayRotationTests {
                 SensorEvent.class.getDeclaredConstructor(int.class);
         constructor.setAccessible(true);
         final SensorEvent event = constructor.newInstance(1);
-        event.sensor = mFakeSensor;
+        event.sensor = mFakeOrientationSensor;
         event.values[0] = rotation;
         event.timestamp = SystemClock.elapsedRealtimeNanos();
         return event;
@@ -691,6 +692,43 @@ public class DisplayRotationTests {
                 SCREEN_ORIENTATION_SENSOR, Surface.ROTATION_0));
     }
 
+    // ====================================================
+    // Tests for half-fold auto-rotate override of rotation
+    // ====================================================
+    @Test
+    public void testUpdatesRotationWhenSensorUpdates_RotationLocked_HalfFolded() throws Exception {
+        mBuilder.setSupportHalfFoldAutoRotateOverride(true);
+        mBuilder.build();
+        configureDisplayRotation(SCREEN_ORIENTATION_LANDSCAPE, false, false);
+
+        enableOrientationSensor();
+
+        mTarget.foldStateChanged(DeviceStateController.FoldState.OPEN);
+        freezeRotation(Surface.ROTATION_270);
+
+        mOrientationSensorListener.onSensorChanged(createSensorEvent(Surface.ROTATION_0));
+        assertTrue(waitForUiHandler());
+        // No rotation...
+        assertEquals(Surface.ROTATION_270, mTarget.rotationForOrientation(
+                SCREEN_ORIENTATION_UNSPECIFIED, Surface.ROTATION_0));
+
+        // ... until half-fold
+        mTarget.foldStateChanged(DeviceStateController.FoldState.HALF_FOLDED);
+        assertTrue(waitForUiHandler());
+        verify(sMockWm).updateRotation(false, false);
+        assertTrue(waitForUiHandler());
+        assertEquals(Surface.ROTATION_0, mTarget.rotationForOrientation(
+                SCREEN_ORIENTATION_UNSPECIFIED, Surface.ROTATION_0));
+
+        // ... then transition back to flat
+        mTarget.foldStateChanged(DeviceStateController.FoldState.OPEN);
+        assertTrue(waitForUiHandler());
+        verify(sMockWm, atLeast(1)).updateRotation(false, false);
+        assertTrue(waitForUiHandler());
+        assertEquals(Surface.ROTATION_270, mTarget.rotationForOrientation(
+                SCREEN_ORIENTATION_UNSPECIFIED, Surface.ROTATION_0));
+    }
+
     // =================================
     // Tests for Policy based Rotation
     // =================================
@@ -884,6 +922,7 @@ public class DisplayRotationTests {
     private class DisplayRotationBuilder {
         private boolean mIsDefaultDisplay = true;
         private boolean mSupportAutoRotation = true;
+        private boolean mSupportHalfFoldAutoRotateOverride = false;
 
         private int mLidOpenRotation = WindowManagerPolicy.WindowManagerFuncs.LID_ABSENT;
         private int mCarDockRotation;
@@ -920,6 +959,12 @@ public class DisplayRotationTests {
             return this;
         }
 
+        private DisplayRotationBuilder setSupportHalfFoldAutoRotateOverride(
+                boolean supportHalfFoldAutoRotateOverride) {
+            mSupportHalfFoldAutoRotateOverride = supportHalfFoldAutoRotateOverride;
+            return this;
+        }
+
         private void captureObservers() {
             ArgumentCaptor<ContentObserver> captor = ArgumentCaptor.forClass(
                     ContentObserver.class);
@@ -1032,9 +1077,13 @@ public class DisplayRotationTests {
             mMockSensorManager = mock(SensorManager.class);
             when(mMockContext.getSystemService(Context.SENSOR_SERVICE))
                     .thenReturn(mMockSensorManager);
-            mFakeSensor = createSensor(Sensor.TYPE_DEVICE_ORIENTATION);
+            mFakeOrientationSensor = createSensor(Sensor.TYPE_DEVICE_ORIENTATION);
             when(mMockSensorManager.getSensorList(Sensor.TYPE_DEVICE_ORIENTATION)).thenReturn(
-                    Collections.singletonList(mFakeSensor));
+                    Collections.singletonList(mFakeOrientationSensor));
+
+            when(mMockContext.getResources().getBoolean(
+                    com.android.internal.R.bool.config_windowManagerHalfFoldAutoRotateOverride))
+                    .thenReturn(mSupportHalfFoldAutoRotateOverride);
 
             mMockResolver = mock(ContentResolver.class);
             when(mMockContext.getContentResolver()).thenReturn(mMockResolver);