Now it is dimmable by PWM 
:
I don’t think that this SPI screen is DPMS compliant… No it never switch off backlight even when Touch Display Plugin screensaver is activated.
In fact I just need to ON/OFF the screen so I found the plugin “gpio control” it was almost perfect to switch off my screen with my GPIO but it doesn’t work anymore with Volumio 3 
Is there a way to trigger a command line, a script or something when player stop/start on Volumio 3 ?
May be I could modify “touch_display/index.js” to execute my gpio write 3 0 when screensaver is activated… 