When pressing the Android power button, the lcd backlight turn on and off. But from past one day, my lcd backlight does not turn on. After pressing like 15 to 20 times, the backlight turn on for a few minutes and then it again goes off. When I was performing the power button pressing operation I found out that it generated a bug report and I thought to analyse it. Here what it says about the backlight:
<6>[59171.668361,2] isl98611 backlight off
<6>[59171.777714,7] Report pwrkey release event at: 2017-03-27 02:23:47 UTC
<6>[59171.803292,5] isl98611 backlight on
<3>[59171.850005,7] wlan: [9525:E :WDA] Failure in host offload REQ WDI API, free all the memory 3
<36>[59171.900305,4] type=1400 audit(1490581427.758:36571): avc: denied { ioctl } for uid=1000 pid=4063 comm="Binder_5" path="socket:[2630050]" dev="sockfs" ino=2630050 ioctlcmd=7704 scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=unix_stream_socket permissive=0
<36>[59171.900723,4] type=1400 audit(1490581427.758:36572): avc: denied { ioctl } for uid=1000 pid=4063 comm="Binder_5" path="socket:[2630050]" dev="sockfs" ino=2630050 ioctlcmd=7704 scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=unix_stream_socket permissive=0
<6>[59171.904836,6] stml0xx spi0.0: Sending Stowed status 0, als 490, prox 0
<6>[59172.275559,7] Report pwrkey press event at: 2017-03-27 02:23:48 UTC
<6>[59172.431993,7] Report pwrkey release event at: 2017-03-27 02:23:48 UTC
<6>[59172.630772,7] Report pwrkey press event at: 2017-03-27 02:23:48 UTC
<6>[59172.762033,7] Report pwrkey release event at: 2017-03-27 02:23:48 UTC
<6>[59172.972182,7] isl98611 backlight off
<3>[59173.070426,5] wlan: [9525:E :WDA] Failure in host offload REQ WDI API, free all the memory 3
<6>[59173.136285,6] isl98611 backlight on
-----And so on, Here i was pressing the power button ON and OFF ------
------ BACKLIGHTS ------
LCD brightness=0
Button brightness=*** /sys/class/leds/button-backlight/brightness: No such file or directory
Keyboard brightness=*** /sys/class/leds/keyboard-backlight/brightness: No such file or directory
ALS mode=*** /sys/class/leds/lcd-backlight/als: No such file or directory
LCD driver registers:
*** /sys/class/leds/lcd-backlight/registers: No such file or directory
UPDATE: After watching the DisplayPowerState code, I observed that it also logs these information.
Display Power Controller Locked State:
mDisplayReadyLocked=true
mPendingRequestLocked=policy=DOZE, useProximitySensor=false, screenBrightness=70, screenAutoBrightnessAdjustment=-0.02734375, brightnessSetByUser=true, useAutoBrightness=true, blockScreenOn=false, lowPowerMode=false, boostScreenBrightness=false, dozeScreenBrightness=30, dozeScreenState=OFF, buttonBrightnessOverride=-1
mPendingRequestChangedLocked=false
mPendingWaitForNegativeProximityLocked=false
mPendingUpdatePowerStateLocked=false
Display Power Controller Configuration:
mScreenBrightnessDozeConfig=17
mScreenBrightnessDimConfig=10
mScreenBrightnessDarkConfig=1
mScreenBrightnessRangeMinimum=1
mScreenBrightnessRangeMaximum=256
mUseSoftwareAutoBrightnessConfig=true
mAllowAutoBrightnessWhileDozingConfig=false
mColorFadeFadesConfig=false
Display Power Controller Thread State:
mPowerRequest=policy=DOZE, useProximitySensor=false, screenBrightness=70, screenAutoBrightnessAdjustment=-0.02734375, brightnessSetByUser=true, useAutoBrightness=true, blockScreenOn=false, lowPowerMode=false, boostScreenBrightness=false, dozeScreenBrightness=30, dozeScreenState=OFF, buttonBrightnessOverride=-1
mWaitingForNegativeProximity=false
mProximitySensor={Sensor name="Proximity sensor", vendor="TAOS", version=1, type=8, maxRange=100.0, resolution=100.0, power=0.0467, minDelay=0}
mProximitySensorEnabled=false
mProximityThreshold=5.0
mProximity=Unknown
mPendingProximity=Unknown
mPendingProximityDebounceTime=-1 (59223063 ms ago)
mScreenOffBecauseOfProximity=false
mAppliedAutoBrightness=false
mAppliedDimming=true
mAppliedLowPower=false
mPendingScreenOnUnblocker=null
mPendingScreenOff=false
mReportedToPolicy=REPORTED_TO_POLICY_SCREEN_OFF
mScreenBrightnessRampAnimator.isAnimating()=false
mColorFadeOnAnimator.isStarted()=false
mColorFadeOffAnimator.isStarted()=false
Display Power State:
mScreenState=OFF
mScreenBrightness=0
mButtonBrightness=0
mScreenReady=true
mScreenUpdatePending=false
mColorFadePrepared=false
mColorFadeLevel=0.0
mColorFadeReady=true
mColorFadeDrawPending=false
Photonic Modulator State:
mPendingState=OFF
mPendingBacklight=0
mActualState=OFF
mActualBacklight=0
mStateChangeInProgress=false
mBacklightChangeInProgress=false
mPendingButtonLight=0
mActualButtonLight=0
Color Fade State:
mPrepared=false
mMode=1
mDisplayLayerStack=0
mDisplayWidth=1080
mDisplayHeight=1920
mSurfaceVisible=false
mSurfaceAlpha=0.0
Automatic Brightness Controller Configuration:
mScreenAutoBrightnessSpline=MonotoneCubicSpline{[(0.0, 0.01953125: 0.0078125), (2.0, 0.03515625: 0.0063476563), (10.0, 0.07421875: 0.0032226562), (50.0, 0.13671875: 0.002001953), (90.0, 0.234375: 0.0031738281), (100.0, 0.2734375: 0.0), (150.0, 0.2734375: 0.0), (200.0, 0.2734375: 0.0), (300.0, 0.2734375: 0.0), (400.0, 0.2734375: 0.0), (500.0, 0.40625: 8.0078124E-4), (800.0, 0.48828125: 2.734375E-4), (1000.0, 0.54296875: 1.8229167E-4), (1300.0, 0.5703125: 1.1795343E-4), (3000.0, 0.81640625: 8.995864E-5), (4000.0, 0.8515625: 3.564453E-5), (8000.0, 0.99609375: 0.0), (20000.0, 0.99609375: 0.0), (30000.0, 1.0: 3.90625E-7)]}
mScreenBrightnessRangeMinimum=1
mScreenBrightnessRangeMaximum=256
mLightSensorWarmUpTimeConfig=0
mBrighteningLightDebounceConfig=2000
mDarkeningLightDebounceConfig=8000
mResetAmbientLuxAfterWarmUpConfig=true
Automatic Brightness Controller State:
mLightSensor={Sensor name="Ambient Light sensor", vendor="TAOS", version=1, type=5, maxRange=27000.0, resolution=1.0, power=0.25, minDelay=0}
mTwilight.getCurrentState()={TwilightState: isNight=false, mYesterdaySunset=26 Mar 2017 6:52:39 p.m., mTodaySunrise=27 Mar 2017 5:58:44 a.m., mTodaySunset=27 Mar 2017 6:52:42 p.m., mTomorrowSunrise=28 Mar 2017 5:58:03 a.m.}
mLightSensorEnabled=false
mLightSensorEnableTime=59170878 (52192 ms ago)
mAmbientLux=489.99997
mBrighteningLuxThreshold=539.0
mDarkeningLuxThreshold=391.99997
mLastObservedLux=518.0
mLastObservedLuxTime=59186385 (36685 ms ago)
mRecentLightSamples=0
mAmbientLightRingBuffer=[]
mScreenAutoBrightness=99
mScreenAutoBrightnessAdjustment=-0.02734375
mLastScreenAutoBrightnessGamma=1.0304959
mDozing=true
mHbmSessionLimit=180000
mHbmDailyLimit=0
mHbmOn=false
mLimitHbm=false
mLastHbmStartTime=0
mHbmDailyDuration=0
Does this mean anything or is it a hardware problem, or should a software reinstall solve it.
