LightSensorController extraction from BrightnessClamperContorller

Also fixed: sensor restart on display changed, sensor registration to comply with ABC

Bug: b/343792639
Test: atest BrightnessClamperControllerTest, atest LightSensorControllerTest
Flag: EXEMPT bugfix, mechanical refactoring
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:2726e78d86b557f3df8573a5a9b11948e46afd0f)
Merged-In: Icddf78defc8fdba83c4d210d12851c7d94adb8b1
Change-Id: Icddf78defc8fdba83c4d210d12851c7d94adb8b1

5 files changed, 465 insertions, 149 deletions

diff --git a/services/core/java/com/android/server/display/DisplayPowerController.java b/services/core/java/com/android/server/display/DisplayPowerController.java
index ae59d491b8f4..df768dcc564f 100644
--- a/services/core/java/com/android/server/display/DisplayPowerController.java
+++ b/services/core/java/com/android/server/display/DisplayPowerController.java
@@ -587,7 +587,8 @@ final class DisplayPowerController implements AutomaticBrightnessController.Call
                         mUniqueDisplayId,
                         mThermalBrightnessThrottlingDataId,
                         logicalDisplay.getPowerThrottlingDataIdLocked(),
-                        mDisplayDeviceConfig), mContext, flags, mSensorManager);
+                        mDisplayDeviceConfig,
+                        mDisplayId), mContext, flags, mSensorManager);
         // Seed the cached brightness
         saveBrightnessInfo(getScreenBrightnessSetting());
         mAutomaticBrightnessStrategy =
@@ -892,7 +893,8 @@ final class DisplayPowerController implements AutomaticBrightnessController.Call
             // will call updatePowerState if needed.
             mBrightnessClamperController.onDisplayChanged(
                     new BrightnessClamperController.DisplayDeviceData(uniqueId,
-                        thermalBrightnessThrottlingDataId, powerThrottlingDataId, config));
+                            thermalBrightnessThrottlingDataId, powerThrottlingDataId,
+                            config, mDisplayId));
 
             if (changed) {
                 updatePowerState();
diff --git a/services/core/java/com/android/server/display/brightness/clamper/BrightnessClamperController.java b/services/core/java/com/android/server/display/brightness/clamper/BrightnessClamperController.java
index 101ad307f50a..220640270e02 100644
--- a/services/core/java/com/android/server/display/brightness/clamper/BrightnessClamperController.java
+++ b/services/core/java/com/android/server/display/brightness/clamper/BrightnessClamperController.java
@@ -23,23 +23,17 @@ import static com.android.server.display.brightness.clamper.BrightnessClamper.Ty
 import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.content.Context;
-import android.content.res.Resources;
-import android.hardware.Sensor;
-import android.hardware.SensorEvent;
-import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
 import android.hardware.display.BrightnessInfo;
 import android.hardware.display.DisplayManagerInternal;
 import android.os.Handler;
 import android.os.HandlerExecutor;
 import android.os.PowerManager;
-import android.os.SystemClock;
 import android.provider.DeviceConfig;
 import android.provider.DeviceConfigInterface;
 import android.util.IndentingPrintWriter;
 import android.util.Slog;
 
-import com.android.internal.R;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.server.display.DisplayBrightnessState;
 import com.android.server.display.DisplayDeviceConfig;
@@ -50,30 +44,22 @@ import com.android.server.display.brightness.BrightnessReason;
 import com.android.server.display.config.SensorData;
 import com.android.server.display.feature.DeviceConfigParameterProvider;
 import com.android.server.display.feature.DisplayManagerFlags;
-import com.android.server.display.utils.AmbientFilter;
-import com.android.server.display.utils.AmbientFilterFactory;
-import com.android.server.display.utils.DebugUtils;
-import com.android.server.display.utils.SensorUtils;
 
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.Executor;
-import java.util.concurrent.TimeUnit;
 
 /**
  * Clampers controller, all in DisplayControllerHandler
  */
 public class BrightnessClamperController {
     private static final String TAG = "BrightnessClamperController";
-    // To enable these logs, run:
-    // 'adb shell setprop persist.log.tag.BrightnessClamperController DEBUG && adb reboot'
-    private static final boolean DEBUG = DebugUtils.isDebuggable(TAG);
-    public static final float INVALID_LUX = -1f;
 
     private final DeviceConfigParameterProvider mDeviceConfigParameterProvider;
     private final Handler mHandler;
-    private final SensorManager mSensorManager;
+    private final LightSensorController mLightSensorController;
+
     private final ClamperChangeListener mClamperChangeListenerExternal;
     private final Executor mExecutor;
     private final List<BrightnessClamper<? super DisplayDeviceData>> mClampers;
@@ -85,70 +71,49 @@ public class BrightnessClamperController {
     private float mCustomAnimationRate = DisplayBrightnessState.CUSTOM_ANIMATION_RATE_NOT_SET;
     @Nullable
     private Type mClamperType = null;
-    private final SensorEventListener mLightSensorListener;
-    private Sensor mRegisteredLightSensor = null;
-    private Sensor mLightSensor;
-    private String mLightSensorType;
-    private String mLightSensorName;
-    private AmbientFilter mAmbientFilter;
-    private final DisplayDeviceConfig mDisplayDeviceConfig;
-    private final Resources mResources;
-    private final int mLightSensorRate;
-
-    private final Injector mInjector;
+
     private boolean mClamperApplied = false;
 
+    private final LightSensorController.LightSensorListener mLightSensorListener =
+            new LightSensorController.LightSensorListener() {
+                @Override
+                public void onAmbientLuxChange(float lux) {
+                    mModifiers.forEach(mModifier -> mModifier.setAmbientLux(lux));
+                }
+            };
+
     public BrightnessClamperController(Handler handler,
             ClamperChangeListener clamperChangeListener, DisplayDeviceData data, Context context,
             DisplayManagerFlags flags, SensorManager sensorManager) {
-        this(null, handler, clamperChangeListener, data, context, flags, sensorManager);
+        this(new Injector(), handler, clamperChangeListener, data, context, flags, sensorManager);
     }
 
     @VisibleForTesting
     BrightnessClamperController(Injector injector, Handler handler,
             ClamperChangeListener clamperChangeListener, DisplayDeviceData data, Context context,
             DisplayManagerFlags flags, SensorManager sensorManager) {
-        mInjector = injector == null ? new Injector() : injector;
-        mDeviceConfigParameterProvider = mInjector.getDeviceConfigParameterProvider();
+        mDeviceConfigParameterProvider = injector.getDeviceConfigParameterProvider();
         mHandler = handler;
-        mSensorManager = sensorManager;
-        mDisplayDeviceConfig = data.mDisplayDeviceConfig;
-        mLightSensorListener = new SensorEventListener() {
-            @Override
-            public void onSensorChanged(SensorEvent event) {
-                long now = SystemClock.elapsedRealtime();
-                mAmbientFilter.addValue(TimeUnit.NANOSECONDS.toMillis(event.timestamp),
-                        event.values[0]);
-                final float lux = mAmbientFilter.getEstimate(now);
-                mModifiers.forEach(mModifier -> mModifier.setAmbientLux(lux));
-            }
-
-            @Override
-            public void onAccuracyChanged(Sensor sensor, int accuracy) {
-                // unused
-            }
-        };
+        mLightSensorController = injector.getLightSensorController(sensorManager, context,
+                mLightSensorListener, mHandler);
 
         mClamperChangeListenerExternal = clamperChangeListener;
         mExecutor = new HandlerExecutor(handler);
-        mResources = context.getResources();
-        mLightSensorRate = context.getResources().getInteger(
-                R.integer.config_autoBrightnessLightSensorRate);
 
         Runnable clamperChangeRunnableInternal = this::recalculateBrightnessCap;
-
         ClamperChangeListener clamperChangeListenerInternal = () -> {
             if (!mHandler.hasCallbacks(clamperChangeRunnableInternal)) {
                 mHandler.post(clamperChangeRunnableInternal);
             }
         };
 
-        mClampers = mInjector.getClampers(handler, clamperChangeListenerInternal, data, flags,
+        mClampers = injector.getClampers(handler, clamperChangeListenerInternal, data, flags,
                 context);
-        mModifiers = mInjector.getModifiers(flags, context, handler, clamperChangeListener,
-                data.mDisplayDeviceConfig, mSensorManager);
+        mModifiers = injector.getModifiers(flags, context, handler, clamperChangeListener,
+                data.mDisplayDeviceConfig);
         mOnPropertiesChangedListener =
                 properties -> mClampers.forEach(BrightnessClamper::onDeviceConfigChanged);
+        mLightSensorController.configure(data.getAmbientLightSensor(), data.getDisplayId());
         start();
     }
 
@@ -156,7 +121,9 @@ public class BrightnessClamperController {
      * Should be called when display changed. Forwards the call to individual clampers
      */
     public void onDisplayChanged(DisplayDeviceData data) {
+        mLightSensorController.configure(data.getAmbientLightSensor(), data.getDisplayId());
         mClampers.forEach(clamper -> clamper.onDisplayChanged(data));
+        adjustLightSensorSubscription();
     }
 
     /**
@@ -184,9 +151,9 @@ public class BrightnessClamperController {
         }
 
         if (displayState != STATE_ON) {
-            unregisterSensorListener();
+            mLightSensorController.stop();
         } else {
-            maybeRegisterLightSensor();
+            adjustLightSensorSubscription();
         }
 
         for (int i = 0; i < mModifiers.size(); i++) {
@@ -231,9 +198,8 @@ public class BrightnessClamperController {
         writer.println("  mBrightnessCap: " + mBrightnessCap);
         writer.println("  mClamperType: " + mClamperType);
         writer.println("  mClamperApplied: " + mClamperApplied);
-        writer.println("  mLightSensor=" + mLightSensor);
-        writer.println("  mRegisteredLightSensor=" + mRegisteredLightSensor);
         IndentingPrintWriter ipw = new IndentingPrintWriter(writer, "    ");
+        mLightSensorController.dump(ipw);
         mClampers.forEach(clamper -> clamper.dump(ipw));
         mModifiers.forEach(modifier -> modifier.dump(ipw));
     }
@@ -245,6 +211,7 @@ public class BrightnessClamperController {
     public void stop() {
         mDeviceConfigParameterProvider.removeOnPropertiesChangedListener(
                 mOnPropertiesChangedListener);
+        mLightSensorController.stop();
         mClampers.forEach(BrightnessClamper::stop);
         mModifiers.forEach(BrightnessStateModifier::stop);
     }
@@ -281,10 +248,15 @@ public class BrightnessClamperController {
         if (!mClampers.isEmpty()) {
             mDeviceConfigParameterProvider.addOnPropertiesChangedListener(
                     mExecutor, mOnPropertiesChangedListener);
-            reloadLightSensorData(mDisplayDeviceConfig);
-            mLightSensor = mInjector.getLightSensor(
-                    mSensorManager, mLightSensorType, mLightSensorName);
-            maybeRegisterLightSensor();
+        }
+        adjustLightSensorSubscription();
+    }
+
+    private void adjustLightSensorSubscription() {
+        if (mModifiers.stream().anyMatch(BrightnessStateModifier::shouldListenToLightSensor)) {
+            mLightSensorController.restart();
+        } else {
+            mLightSensorController.stop();
         }
     }
 
@@ -323,7 +295,7 @@ public class BrightnessClamperController {
 
         List<BrightnessStateModifier> getModifiers(DisplayManagerFlags flags, Context context,
                 Handler handler, ClamperChangeListener listener,
-                DisplayDeviceConfig displayDeviceConfig, SensorManager sensorManager) {
+                DisplayDeviceConfig displayDeviceConfig) {
             List<BrightnessStateModifier> modifiers = new ArrayList<>();
             modifiers.add(new DisplayDimModifier(context));
             modifiers.add(new BrightnessLowPowerModeModifier());
@@ -335,11 +307,12 @@ public class BrightnessClamperController {
             return modifiers;
         }
 
-        Sensor getLightSensor(SensorManager sensorManager, String type, String name) {
-            return SensorUtils.findSensor(sensorManager, type,
-                    name, Sensor.TYPE_LIGHT);
+        LightSensorController getLightSensorController(SensorManager sensorManager,
+                Context context, LightSensorController.LightSensorListener listener,
+                Handler handler) {
+            return new LightSensorController(sensorManager, context.getResources(),
+                    listener, handler);
         }
-
     }
 
     /**
@@ -354,17 +327,21 @@ public class BrightnessClamperController {
         private final String mThermalThrottlingDataId;
         @NonNull
         private final String mPowerThrottlingDataId;
-
+        @NonNull
         private final DisplayDeviceConfig mDisplayDeviceConfig;
 
+        private final int mDisplayId;
+
         public DisplayDeviceData(@NonNull String uniqueDisplayId,
                 @NonNull String thermalThrottlingDataId,
                 @NonNull String powerThrottlingDataId,
-                @NonNull DisplayDeviceConfig displayDeviceConfig) {
+                @NonNull DisplayDeviceConfig displayDeviceConfig,
+                int displayId) {
             mUniqueDisplayId = uniqueDisplayId;
             mThermalThrottlingDataId = thermalThrottlingDataId;
             mPowerThrottlingDataId = powerThrottlingDataId;
             mDisplayDeviceConfig = displayDeviceConfig;
+            mDisplayId = displayId;
         }
 
 
@@ -412,55 +389,18 @@ public class BrightnessClamperController {
         }
 
         @NonNull
+        @Override
         public SensorData getTempSensor() {
             return mDisplayDeviceConfig.getTempSensor();
         }
-    }
-
-    private void maybeRegisterLightSensor() {
-        if (mModifiers.stream().noneMatch(BrightnessStateModifier::shouldListenToLightSensor)) {
-            return;
-        }
-
-        if (mRegisteredLightSensor == mLightSensor) {
-            return;
-        }
 
-        if (mRegisteredLightSensor != null) {
-            unregisterSensorListener();
-        }
-
-        mAmbientFilter = AmbientFilterFactory.createBrightnessFilter(TAG, mResources);
-        mSensorManager.registerListener(mLightSensorListener,
-                mLightSensor, mLightSensorRate * 1000, mHandler);
-        mRegisteredLightSensor = mLightSensor;
-
-        if (DEBUG) {
-            Slog.d(TAG, "maybeRegisterLightSensor");
-        }
-    }
-
-    private void unregisterSensorListener() {
-        mSensorManager.unregisterListener(mLightSensorListener);
-        mRegisteredLightSensor = null;
-        mModifiers.forEach(mModifier -> mModifier.setAmbientLux(INVALID_LUX)); // set lux to invalid
-        if (DEBUG) {
-            Slog.d(TAG, "unregisterSensorListener");
+        @NonNull
+        SensorData getAmbientLightSensor() {
+            return mDisplayDeviceConfig.getAmbientLightSensor();
         }
-    }
 
-    private void reloadLightSensorData(DisplayDeviceConfig displayDeviceConfig) {
-        // The displayDeviceConfig (ddc) contains display specific preferences. When loaded,
-        // it naturally falls back to the global config.xml.
-        if (displayDeviceConfig != null
-                && displayDeviceConfig.getAmbientLightSensor() != null) {
-            // This covers both the ddc and the config.xml fallback
-            mLightSensorType = displayDeviceConfig.getAmbientLightSensor().type;
-            mLightSensorName = displayDeviceConfig.getAmbientLightSensor().name;
-        } else if (mLightSensorName == null && mLightSensorType == null) {
-            mLightSensorType = mResources.getString(
-                    com.android.internal.R.string.config_displayLightSensorType);
-            mLightSensorName = "";
+        int getDisplayId() {
+            return mDisplayId;
         }
     }
 }
diff --git a/services/core/java/com/android/server/display/brightness/clamper/LightSensorController.java b/services/core/java/com/android/server/display/brightness/clamper/LightSensorController.java
new file mode 100644
index 000000000000..d89dd28c4a89
--- /dev/null
+++ b/services/core/java/com/android/server/display/brightness/clamper/LightSensorController.java
@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2024 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.display.brightness.clamper;
+
+import android.annotation.Nullable;
+import android.content.res.Resources;
+import android.hardware.Sensor;
+import android.hardware.SensorEvent;
+import android.hardware.SensorEventListener;
+import android.hardware.SensorManager;
+import android.os.Handler;
+import android.os.SystemClock;
+import android.util.Slog;
+import android.view.Display;
+
+import com.android.internal.R;
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.server.display.config.SensorData;
+import com.android.server.display.utils.AmbientFilter;
+import com.android.server.display.utils.AmbientFilterFactory;
+import com.android.server.display.utils.DebugUtils;
+import com.android.server.display.utils.SensorUtils;
+
+import java.io.PrintWriter;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Manages light sensor subscription and notifies its listener about ambient lux changes
+ */
+public class LightSensorController {
+    private static final String TAG = "LightSensorController";
+
+    // To enable these logs, run:
+    // 'adb shell setprop persist.log.tag.LightSensorController DEBUG && adb reboot'
+    private static final boolean DEBUG = DebugUtils.isDebuggable(TAG);
+    static final float INVALID_LUX = -1f;
+
+    private final SensorManager mSensorManager;
+    private final LightSensorListener mLightSensorListener;
+    private final Handler mHandler;
+    private final Injector mInjector;
+    private final AmbientFilter mAmbientFilter;
+
+    private Sensor mLightSensor;
+    private Sensor mRegisteredLightSensor = null;
+    private final int mLightSensorRate;
+
+    private final SensorEventListener mLightSensorEventListener = new SensorEventListener() {
+        @Override
+        public void onSensorChanged(SensorEvent event) {
+            long now = mInjector.getTime();
+            mAmbientFilter.addValue(TimeUnit.NANOSECONDS.toMillis(event.timestamp),
+                    event.values[0]);
+            final float lux = mAmbientFilter.getEstimate(now);
+            mLightSensorListener.onAmbientLuxChange(lux);
+        }
+
+        @Override
+        public void onAccuracyChanged(Sensor sensor, int accuracy) {
+            // unused
+        }
+    };
+
+    LightSensorController(SensorManager sensorManager, Resources resources,
+            LightSensorListener listener, Handler handler) {
+        this(sensorManager, resources, listener, handler, new Injector());
+    }
+
+    @VisibleForTesting
+    LightSensorController(SensorManager sensorManager, Resources resources,
+            LightSensorListener listener, Handler handler, Injector injector) {
+        mSensorManager = sensorManager;
+        mLightSensorRate = injector.getLightSensorRate(resources);
+        mAmbientFilter = injector.getAmbientFilter(resources);
+        mLightSensorListener = listener;
+        mHandler = handler;
+        mInjector = injector;
+    }
+
+    void restart() {
+        if (mRegisteredLightSensor == mLightSensor) {
+            return;
+        }
+        if (mRegisteredLightSensor != null) {
+            stop();
+        }
+        if (mLightSensor == null) {
+            return;
+        }
+
+        mSensorManager.registerListener(mLightSensorEventListener,
+                mLightSensor, mLightSensorRate * 1000, mHandler);
+        mRegisteredLightSensor = mLightSensor;
+
+        if (DEBUG) {
+            Slog.d(TAG, "restart");
+        }
+    }
+
+    void stop() {
+        if (mRegisteredLightSensor == null) {
+            return;
+        }
+        mSensorManager.unregisterListener(mLightSensorEventListener);
+        mRegisteredLightSensor = null;
+        mAmbientFilter.clear();
+        mLightSensorListener.onAmbientLuxChange(INVALID_LUX);
+        if (DEBUG) {
+            Slog.d(TAG, "stop");
+        }
+    }
+
+    void configure(SensorData sensorData, int displayId) {
+        final int fallbackType = displayId == Display.DEFAULT_DISPLAY
+                ? Sensor.TYPE_LIGHT : SensorUtils.NO_FALLBACK;
+        mLightSensor = mInjector.getLightSensor(mSensorManager, sensorData, fallbackType);
+    }
+
+    void dump(PrintWriter writer) {
+        writer.println("LightSensorController");
+        writer.println("  mLightSensor=" + mLightSensor);
+        writer.println("  mRegisteredLightSensor=" + mRegisteredLightSensor);
+    }
+
+    static class Injector {
+        @Nullable
+        Sensor getLightSensor(SensorManager sensorManager, SensorData sensorData,
+                int fallbackType) {
+            return SensorUtils.findSensor(sensorManager, sensorData, fallbackType);
+        }
+
+        AmbientFilter getAmbientFilter(Resources resources) {
+            return AmbientFilterFactory.createBrightnessFilter(TAG, resources);
+        }
+
+        int getLightSensorRate(Resources resources) {
+            return resources.getInteger(R.integer.config_autoBrightnessLightSensorRate);
+        }
+
+        // should be consistent with SensorEvent.timestamp
+        long getTime() {
+            return SystemClock.elapsedRealtime();
+        }
+    }
+
+    interface  LightSensorListener {
+        void onAmbientLuxChange(float ambientLux);
+    }
+}
diff --git a/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/BrightnessClamperControllerTest.java b/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/BrightnessClamperControllerTest.java
index 69043f5704de..e982153acbd1 100644
--- a/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/BrightnessClamperControllerTest.java
+++ b/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/BrightnessClamperControllerTest.java
@@ -16,19 +16,19 @@
 
 package com.android.server.display.brightness.clamper;
 
+import static android.view.Display.STATE_OFF;
 import static android.view.Display.STATE_ON;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.clearInvocations;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 import android.content.Context;
-import android.hardware.Sensor;
-import android.hardware.SensorEventListener;
 import android.hardware.SensorManager;
 import android.hardware.display.BrightnessInfo;
 import android.hardware.display.DisplayManagerInternal;
@@ -40,12 +40,10 @@ import android.testing.TestableContext;
 import androidx.test.filters.SmallTest;
 import androidx.test.platform.app.InstrumentationRegistry;
 
-import com.android.internal.util.test.FakeSettingsProvider;
-import com.android.internal.util.test.FakeSettingsProviderRule;
 import com.android.server.display.DisplayBrightnessState;
 import com.android.server.display.DisplayDeviceConfig;
-import com.android.server.display.TestUtils;
 import com.android.server.display.brightness.BrightnessReason;
+import com.android.server.display.config.SensorData;
 import com.android.server.display.feature.DeviceConfigParameterProvider;
 import com.android.server.display.feature.DisplayManagerFlags;
 import com.android.server.testutils.OffsettableClock;
@@ -63,6 +61,7 @@ import java.util.List;
 @SmallTest
 public class BrightnessClamperControllerTest {
     private static final float FLOAT_TOLERANCE = 0.001f;
+    private static final int DISPLAY_ID = 2;
 
     private final OffsettableClock mClock = new OffsettableClock();
     private final TestHandler mTestHandler = new TestHandler(null, mClock);
@@ -78,8 +77,12 @@ public class BrightnessClamperControllerTest {
     @Mock
     private BrightnessClamperController.DisplayDeviceData mMockDisplayDeviceData;
     @Mock
+    private SensorData mMockSensorData;
+    @Mock
     private DeviceConfigParameterProvider mMockDeviceConfigParameterProvider;
     @Mock
+    private LightSensorController mMockLightSensorController;
+    @Mock
     private BrightnessClamper<BrightnessClamperController.DisplayDeviceData> mMockClamper;
     @Mock
     private DisplayManagerFlags mFlags;
@@ -88,23 +91,17 @@ public class BrightnessClamperControllerTest {
     @Mock
     private DisplayManagerInternal.DisplayPowerRequest mMockRequest;
 
-    Sensor mLightSensor;
-
     @Mock
     private DeviceConfig.Properties mMockProperties;
     private BrightnessClamperController mClamperController;
     private TestInjector mTestInjector;
 
-    @Rule
-    public FakeSettingsProviderRule mSettingsProviderRule = FakeSettingsProvider.rule();
-
     @Before
     public void setUp() throws Exception {
         MockitoAnnotations.initMocks(this);
-        mLightSensor = TestUtils.createSensor(Sensor.TYPE_LIGHT, "Light Sensor");
         mTestInjector = new TestInjector(List.of(mMockClamper), List.of(mMockModifier));
-        when(mSensorManager.getDefaultSensor(anyInt())).thenReturn(mLightSensor);
-        when(mMockModifier.shouldListenToLightSensor()).thenReturn(true);
+        when(mMockDisplayDeviceData.getDisplayId()).thenReturn(DISPLAY_ID);
+        when(mMockDisplayDeviceData.getAmbientLightSensor()).thenReturn(mMockSensorData);
 
         mClamperController = createBrightnessClamperController();
     }
@@ -115,6 +112,25 @@ public class BrightnessClamperControllerTest {
     }
 
     @Test
+    public void testConstructor_ConfiguresLightSensorController() {
+        verify(mMockLightSensorController).configure(mMockSensorData, DISPLAY_ID);
+    }
+
+    @Test
+    public void testConstructor_doesNotStartsLightSensorController() {
+        verify(mMockLightSensorController, never()).restart();
+    }
+
+    @Test
+    public void testConstructor_startsLightSensorController() {
+        when(mMockModifier.shouldListenToLightSensor()).thenReturn(true);
+
+        mClamperController = createBrightnessClamperController();
+
+        verify(mMockLightSensorController).restart();
+    }
+
+    @Test
     public void testStop_RemovesOnPropertiesChangeListener() {
         ArgumentCaptor<DeviceConfig.OnPropertiesChangedListener> captor = ArgumentCaptor.forClass(
                 DeviceConfig.OnPropertiesChangedListener.class);
@@ -152,6 +168,21 @@ public class BrightnessClamperControllerTest {
     }
 
     @Test
+    public void testOnDisplayChanged_doesNotRestartLightSensor() {
+        mClamperController.onDisplayChanged(mMockDisplayDeviceData);
+
+        verify(mMockLightSensorController, never()).restart();
+    }
+
+    @Test
+    public void testOnDisplayChanged_restartsLightSensor() {
+        when(mMockModifier.shouldListenToLightSensor()).thenReturn(true);
+        mClamperController.onDisplayChanged(mMockDisplayDeviceData);
+
+        verify(mMockLightSensorController).restart();
+    }
+
+    @Test
     public void testClamp_AppliesModifier() {
         float initialBrightness = 0.2f;
         boolean initialSlowChange = true;
@@ -161,6 +192,26 @@ public class BrightnessClamperControllerTest {
     }
 
     @Test
+    public void testClamp_restartsLightSensor() {
+        float initialBrightness = 0.2f;
+        boolean initialSlowChange = true;
+        when(mMockModifier.shouldListenToLightSensor()).thenReturn(true);
+        mClamperController.clamp(mMockRequest, initialBrightness, initialSlowChange, STATE_ON);
+
+        verify(mMockLightSensorController).restart();
+    }
+
+    @Test
+    public void testClamp_stopsLightSensor() {
+        float initialBrightness = 0.2f;
+        boolean initialSlowChange = true;
+        clearInvocations(mMockLightSensorController);
+        mClamperController.clamp(mMockRequest, initialBrightness, initialSlowChange, STATE_OFF);
+
+        verify(mMockLightSensorController).stop();
+    }
+
+    @Test
     public void testClamp_inactiveClamperNotApplied() {
         float initialBrightness = 0.8f;
         boolean initialSlowChange = true;
@@ -260,33 +311,17 @@ public class BrightnessClamperControllerTest {
     }
 
     @Test
-    public void testAmbientLuxChanges() throws Exception {
-        ArgumentCaptor<SensorEventListener> listenerCaptor = ArgumentCaptor.forClass(
-                SensorEventListener.class);
-
-        verify(mSensorManager).registerListener(listenerCaptor.capture(), eq(mLightSensor),
-                anyInt(), any(Handler.class));
-        SensorEventListener listener = listenerCaptor.getValue();
-
-        when(mSensorManager.getSensorList(eq(Sensor.TYPE_ALL))).thenReturn(List.of(mLightSensor));
-
-        float initialBrightness = 0.8f;
-        boolean initialSlowChange = true;
-
-        DisplayBrightnessState state = mClamperController.clamp(mMockRequest, initialBrightness,
-                initialSlowChange, STATE_ON);
-        assertEquals(initialBrightness, state.getBrightness(), FLOAT_TOLERANCE);
+    public void testAmbientLuxChanges() {
+        mTestInjector.mCapturedLightSensorListener.onAmbientLuxChange(50);
 
-        listener.onSensorChanged(TestUtils.createSensorEvent(mLightSensor, 50, mClock.now()));
         verify(mMockModifier).setAmbientLux(50);
-
-        listener.onSensorChanged(TestUtils.createSensorEvent(mLightSensor, 300, mClock.now()));
-        verify(mMockModifier).setAmbientLux(300);
     }
 
     @Test
     public void testStop() {
+        clearInvocations(mMockLightSensorController);
         mClamperController.stop();
+        verify(mMockLightSensorController).stop();
         verify(mMockModifier).stop();
         verify(mMockClamper).stop();
     }
@@ -303,6 +338,7 @@ public class BrightnessClamperControllerTest {
         private final List<BrightnessStateModifier> mModifiers;
 
         private BrightnessClamperController.ClamperChangeListener mCapturedChangeListener;
+        private LightSensorController.LightSensorListener mCapturedLightSensorListener;
 
         private TestInjector(
                 List<BrightnessClamper<? super BrightnessClamperController.DisplayDeviceData>>
@@ -330,8 +366,15 @@ public class BrightnessClamperControllerTest {
         @Override
         List<BrightnessStateModifier> getModifiers(DisplayManagerFlags flags, Context context,
                 Handler handler, BrightnessClamperController.ClamperChangeListener listener,
-                DisplayDeviceConfig displayDeviceConfig, SensorManager sensorManager) {
+                DisplayDeviceConfig displayDeviceConfig) {
             return mModifiers;
         }
+
+        @Override
+        LightSensorController getLightSensorController(SensorManager sensorManager, Context context,
+                LightSensorController.LightSensorListener listener, Handler handler) {
+            mCapturedLightSensorListener = listener;
+            return mMockLightSensorController;
+        }
     }
 }
diff --git a/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/LightSensorControllerTest.kt b/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/LightSensorControllerTest.kt
new file mode 100644
index 000000000000..b742d021f2e9
--- /dev/null
+++ b/services/tests/displayservicetests/src/com/android/server/display/brightness/clamper/LightSensorControllerTest.kt
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 2023 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.display.brightness.clamper
+
+import android.content.res.Resources
+import android.hardware.Sensor
+import android.hardware.SensorEventListener
+import android.hardware.SensorManager
+import android.os.Handler
+import androidx.test.filters.SmallTest
+import com.android.server.display.TestUtils
+import com.android.server.display.brightness.clamper.LightSensorController.Injector
+import com.android.server.display.brightness.clamper.LightSensorController.LightSensorListener
+import com.android.server.display.config.SensorData
+import com.android.server.display.utils.AmbientFilter
+import org.junit.Before
+import org.mockito.kotlin.any
+import org.mockito.kotlin.argumentCaptor
+import org.mockito.kotlin.eq
+import org.mockito.kotlin.inOrder
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.verify
+import org.mockito.kotlin.verifyNoMoreInteractions
+import org.mockito.kotlin.whenever
+
+private const val LIGHT_SENSOR_RATE: Int = 10
+private const val DISPLAY_ID: Int = 3
+private const val NOW: Long = 3_000
+
+@SmallTest
+class LightSensorControllerTest {
+
+    private val mockSensorManager: SensorManager = mock()
+    private val mockResources: Resources = mock()
+    private val mockLightSensorListener: LightSensorListener = mock()
+    private val mockHandler: Handler = mock()
+    private val mockAmbientFilter: AmbientFilter = mock()
+
+    private val testInjector = TestInjector()
+    private val dummySensorData = SensorData()
+
+    private lateinit var controller: LightSensorController
+
+    @Before
+    fun setUp() {
+        controller = LightSensorController(mockSensorManager, mockResources,
+            mockLightSensorListener, mockHandler, testInjector)
+    }
+
+    fun `does not register light sensor if is not configured`() {
+        controller.restart()
+
+        verifyNoMoreInteractions(mockSensorManager, mockAmbientFilter, mockLightSensorListener)
+    }
+
+    fun `does not register light sensor if missing`() {
+        controller.configure(dummySensorData, DISPLAY_ID)
+        controller.restart()
+
+        verifyNoMoreInteractions(mockSensorManager, mockAmbientFilter, mockLightSensorListener)
+    }
+
+    fun `register light sensor if configured and present`() {
+        testInjector.lightSensor = TestUtils
+                .createSensor(Sensor.TYPE_LIGHT, Sensor.STRING_TYPE_LIGHT)
+        controller.configure(dummySensorData, DISPLAY_ID)
+        controller.restart()
+
+        verify(mockSensorManager).registerListener(any(),
+            testInjector.lightSensor, LIGHT_SENSOR_RATE * 1000, mockHandler)
+        verifyNoMoreInteractions(mockSensorManager, mockAmbientFilter, mockLightSensorListener)
+    }
+
+    fun `register light sensor once if not changed`() {
+        testInjector.lightSensor = TestUtils
+                .createSensor(Sensor.TYPE_LIGHT, Sensor.STRING_TYPE_LIGHT)
+        controller.configure(dummySensorData, DISPLAY_ID)
+
+        controller.restart()
+        controller.restart()
+
+        verify(mockSensorManager).registerListener(any(),
+            testInjector.lightSensor, LIGHT_SENSOR_RATE * 1000, mockHandler)
+        verifyNoMoreInteractions(mockSensorManager, mockAmbientFilter, mockLightSensorListener)
+    }
+
+    fun `register new light sensor and unregister old if changed`() {
+        val lightSensor1 = TestUtils
+                .createSensor(Sensor.TYPE_LIGHT, Sensor.STRING_TYPE_LIGHT)
+        testInjector.lightSensor = lightSensor1
+        controller.configure(dummySensorData, DISPLAY_ID)
+        controller.restart()
+
+        val lightSensor2 = TestUtils
+                .createSensor(Sensor.TYPE_LIGHT, Sensor.STRING_TYPE_LIGHT)
+        testInjector.lightSensor = lightSensor2
+        controller.configure(dummySensorData, DISPLAY_ID)
+        controller.restart()
+
+        inOrder {
+            verify(mockSensorManager).registerListener(any(),
+                lightSensor1, LIGHT_SENSOR_RATE * 1000, mockHandler)
+            verify(mockSensorManager).unregisterListener(any<SensorEventListener>())
+            verify(mockAmbientFilter).clear()
+            verify(mockLightSensorListener).onAmbientLuxChange(LightSensorController.INVALID_LUX)
+            verify(mockSensorManager).registerListener(any(),
+                lightSensor2, LIGHT_SENSOR_RATE * 1000, mockHandler)
+        }
+        verifyNoMoreInteractions(mockSensorManager, mockAmbientFilter, mockLightSensorListener)
+    }
+
+    fun `notifies listener on ambient lux change`() {
+        val expectedLux = 40f
+        val eventLux = 50
+        val eventTime = 60L
+        whenever(mockAmbientFilter.getEstimate(NOW)).thenReturn(expectedLux)
+        val listenerCaptor = argumentCaptor<SensorEventListener>()
+        testInjector.lightSensor = TestUtils
+                .createSensor(Sensor.TYPE_LIGHT, Sensor.STRING_TYPE_LIGHT)
+        controller.configure(dummySensorData, DISPLAY_ID)
+        controller.restart()
+        verify(mockSensorManager).registerListener(listenerCaptor.capture(),
+            eq(testInjector.lightSensor), eq(LIGHT_SENSOR_RATE * 1000), eq(mockHandler))
+
+        val listener = listenerCaptor.lastValue
+        listener.onSensorChanged(TestUtils.createSensorEvent(testInjector.lightSensor,
+            eventLux, eventTime * 1_000_000))
+
+        inOrder {
+            verify(mockAmbientFilter).addValue(eventTime, eventLux.toFloat())
+            verify(mockLightSensorListener).onAmbientLuxChange(expectedLux)
+        }
+    }
+
+    private inner class TestInjector : Injector() {
+        var lightSensor: Sensor? = null
+        override fun getLightSensor(sensorManager: SensorManager?,
+            sensorData: SensorData?, fallbackType: Int): Sensor? {
+            return lightSensor
+        }
+
+        override fun getLightSensorRate(resources: Resources?): Int {
+            return LIGHT_SENSOR_RATE
+        }
+
+        override fun getAmbientFilter(resources: Resources?): AmbientFilter {
+            return mockAmbientFilter
+        }
+
+        override fun getTime(): Long {
+            return NOW
+        }
+    }
+}
\ No newline at end of file