I have a HyperPixel 4 display on a Raspberry Pi 3 B+ and am currently using xscreensaver with the blank only option to blank the screen after a period of time. This is working, but the backlight stays on.
I found that I can use something like echo “0” > /sys/class/backlight/rpi_backlight/brightness to turn off the backlight, but this will then stay off when the screen wakes up on touch.
Is there a way that the backlight can be turned off when the screen blanks and back on when it wakes up?
Basically, a script monitors the screensaver using xscreensaver-command and turns off the backlight when the screen blanks and turns it on when it unblanks.