From 589d64833a4d996d6c4c0bb2cd70d2a6a694a102 Mon Sep 17 00:00:00 2001
From: bquezada <bquezada@google.com>
Date: Wed, 26 May 2021 18:19:50 +0000
Subject: [PATCH] Add batching to Flip to Screen Off.

This reduces power drain when the screen is on and the phone is idle.

Bug: 189253126
Test: atest FaceDownDetectorTest
Change-Id: I1a7712b691654b5d0552171cc7419f34154da300
---
 core/res/res/values/config.xml                    |  3 +++
 core/res/res/values/symbols.xml                   |  1 +
 .../android/server/power/FaceDownDetector.java    | 15 ++++++++++++++-
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 28f18a4124ded..61028d9bbeb3d 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -1792,6 +1792,9 @@
     <!-- Boolean indicating if placing the phone face down will result in a screen off. -->
     <bool name="config_flipToScreenOffEnabled">true</bool>
 
+    <!-- Integer to set a max latency the accelerometer will batch sensor requests with. -->
+    <integer name="config_flipToScreenOffMaxLatencyMicros">2000000</integer>
+
     <!-- Boolean indicating if current platform supports bluetooth SCO for off call
     use cases -->
     <bool name="config_bluetooth_sco_off_call">true</bool>
diff --git a/core/res/res/values/symbols.xml b/core/res/res/values/symbols.xml
index d86c6e7270480..9ebab8fda5890 100644
--- a/core/res/res/values/symbols.xml
+++ b/core/res/res/values/symbols.xml
@@ -276,6 +276,7 @@
   <java-symbol type="bool" name="config_avoidGfxAccel" />
   <java-symbol type="bool" name="config_bluetooth_address_validation" />
   <java-symbol type="bool" name="config_flipToScreenOffEnabled" />
+  <java-symbol type="integer" name="config_flipToScreenOffMaxLatencyMicros" />
   <java-symbol type="bool" name="config_bluetooth_sco_off_call" />
   <java-symbol type="bool" name="config_bluetooth_le_peripheral_mode_supported" />
   <java-symbol type="bool" name="config_bluetooth_hfp_inband_ringing_support" />
diff --git a/services/core/java/com/android/server/power/FaceDownDetector.java b/services/core/java/com/android/server/power/FaceDownDetector.java
index 816c81ddf3059..b237ca27e62d8 100644
--- a/services/core/java/com/android/server/power/FaceDownDetector.java
+++ b/services/core/java/com/android/server/power/FaceDownDetector.java
@@ -77,6 +77,8 @@ public class FaceDownDetector implements SensorEventListener {
 
     private boolean mIsEnabled;
 
+    private int mSensorMaxLatencyMicros;
+
     /**
      * DeviceConfig flag name, determines how long to disable sensor when user interacts while
      * device is flipped.
@@ -202,7 +204,11 @@ public class FaceDownDetector implements SensorEventListener {
         if (mActive != shouldBeActive) {
             if (shouldBeActive) {
                 mSensorManager.registerListener(
-                        this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
+                        this,
+                        mAccelerometer,
+                        SensorManager.SENSOR_DELAY_NORMAL,
+                        mSensorMaxLatencyMicros
+                );
                 if (mPreviousResultType == SCREEN_OFF_RESULT) {
                     logScreenOff();
                 }
@@ -226,6 +232,7 @@ public class FaceDownDetector implements SensorEventListener {
         pw.println("  mFaceDown=" + mFaceDown);
         pw.println("  mActive=" + mActive);
         pw.println("  mLastFlipTime=" + mLastFlipTime);
+        pw.println("  mSensorMaxLatencyMicros=" + mSensorMaxLatencyMicros);
         pw.println("  mUserInteractionBackoffMillis=" + mUserInteractionBackoffMillis);
         pw.println("  mPreviousResultTime=" + mPreviousResultTime);
         pw.println("  mPreviousResultType=" + mPreviousResultType);
@@ -356,6 +363,11 @@ public class FaceDownDetector implements SensorEventListener {
                 3600_000);
     }
 
+    private int getSensorMaxLatencyMicros() {
+        return mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_flipToScreenOffMaxLatencyMicros);
+    }
+
     private float getFloatFlagValue(String key, float defaultValue, float min, float max) {
         final float value = DeviceConfig.getFloat(NAMESPACE_ATTENTION_MANAGER_SERVICE,
                 key,
@@ -416,6 +428,7 @@ public class FaceDownDetector implements SensorEventListener {
         mZAccelerationThreshold = getZAccelerationThreshold();
         mZAccelerationThresholdLenient = mZAccelerationThreshold + 1.0f;
         mTimeThreshold = getTimeThreshold();
+        mSensorMaxLatencyMicros = getSensorMaxLatencyMicros();
         mUserInteractionBackoffMillis = getUserInteractionBackoffMillis();
         final boolean oldEnabled = mIsEnabled;
         mIsEnabled = isEnabled();