From a00cda677956e0553a6de4df8f25ebc9b2b3039e Mon Sep 17 00:00:00 2001 From: Michael Wright Date: Sat, 14 Aug 2021 00:19:12 +0100 Subject: [PATCH] Only update the display when brightness and state are valid. If either are invalid then we're in an indeterminant state and need to wait until that's resolved. This should only happens at boot and then is immediately corrected when we set our initial desired state. By not checking the validity of the to-be-applied state, we're actually turning the display to our assumed state briefly (i.e. OFF) even though we don't know what state we actually want yet. Fixes: 196566901 Fixes: 196274559 Fixes: 195071558 Test: Reboot device, no flicker in boot animation Change-Id: Ie5a4c186e3af31eb8810f5c7014a4e2cc7cdbf91 --- .../java/com/android/server/display/DisplayPowerState.java | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/services/core/java/com/android/server/display/DisplayPowerState.java b/services/core/java/com/android/server/display/DisplayPowerState.java index 6af192371e3da..147050cd271fe 100644 --- a/services/core/java/com/android/server/display/DisplayPowerState.java +++ b/services/core/java/com/android/server/display/DisplayPowerState.java @@ -411,7 +411,7 @@ final class DisplayPowerState { * Updates the state of the screen and backlight asynchronously on a separate thread. */ private final class PhotonicModulator extends Thread { - private static final int INITIAL_SCREEN_STATE = Display.STATE_OFF; // unknown, assume off + private static final int INITIAL_SCREEN_STATE = Display.STATE_UNKNOWN; private static final float INITIAL_BACKLIGHT_FLOAT = PowerManager.BRIGHTNESS_INVALID_FLOAT; private final Object mLock = new Object(); @@ -494,7 +494,9 @@ final class DisplayPowerState { if (!backlightChanged) { mBacklightChangeInProgress = false; } - if (!stateChanged && !backlightChanged) { + boolean valid = state != Display.STATE_UNKNOWN && !Float.isNaN(brightnessState); + boolean changed = stateChanged || backlightChanged; + if (!valid || !changed) { try { mLock.wait(); } catch (InterruptedException ex) {