Tinker Board Forum

Full Version: Raspberry Pi Display
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
I am trying to adjust the brightness on a raspberry pi official display while using android but can't seem to be able to get it to work
(09-26-2019, 08:34 PM)Lordracoon Wrote: [ -> ]I am trying to adjust the brightness on a raspberry pi official display while using android but can't seem to be able to get it to work

hi Lordracoon,

I have one tinker board running Android 6.0.1 Marshmallow v13.14.0.95 
with raspberry pi official display.. brightness can be adjusted from 
Display menu or adb...
Code:
$ adb connect 192.168.0.46
$ adb root
$ adb connect 192.168.0.46
$ adb shell settings put system screen_brightness 102
$ adb shell settings get system screen_brightness
102
$ adb shell
but Asus.. must be using some voodoo magic to get this to work.. ]]]]....
as I can't find the file that holds the brightness value... 

in Android root shell... 
Code:
root@rk3288:/ # find . -name '*brightness' 2>/dev/null                        
./sys/devices/gpio-leds.37/leds/pwr-led/brightness
./sys/devices/gpio-leds.37/leds/pwr-led/max_brightness
./sys/devices/gpio-leds.37/leds/led1-led/brightness
./sys/devices/gpio-leds.37/leds/led1-led/max_brightness
./sys/devices/gpio-leds.37/leds/act-led/brightness
./sys/devices/gpio-leds.37/leds/act-led/max_brightness
=================================
./sys/devices/backlight.29/backlight/rk28_bl/brightness
./sys/devices/backlight.29/backlight/rk28_bl/max_brightness
./sys/devices/backlight.29/backlight/rk28_bl/actual_brightness
======================================
./data/data/com.termux/files/usr/bin/termux-brightness
root@rk3288:/ #
but when i cat brightness or actual_brightness I get 20 ????
and max_brightness is 255...

my other Android tinker board has TinkerOS_Android 7 Nougat V14.3.2.82..
connect HDMI to LG 27UD68P-B 4k monitor.. so Display menu set brightness or
adb shell settings put system screen_brightness 102.. has no effect on LG monitor.. 

hope it helps
----------------
k,