Ubuntu-frame not re-activating after idle-timeout using a touchscreen

Hi, i am using ubuntu-frame with wpe-webkit-mir-kiosk with an raspberry pi 3 connected to a touchscreen display.

When connecting a keyboard to the pi, I can re-activate the ubuntu frame by a keypress. Is there a possibility to re-enable the screen using the touchscreen of the pi?

Thanks, Lukas

Hello @luuu,

thanks for your question. I’ve done some experimentation and what seems to be happening is that when the display is powered off (following the idle timeout) the digitizer hardware is powered off too. Being powered off renders the display unable to detect touch input and wake Frame.

This seems to be quite a common design (two displays out of two tested do this).

Unfortunately, I don’t see any way to address this in software, and the only way to work around it would be to disable the idle timeout.

Best, Alan

hi @alan_g ,

I don"t understand why idle disable mouse/touch with “xset dpms” on X11, my touch is on and i can wake up my screen.

On a touch terminal it’s not possibile to use without this

the idle process must not disable /dev/event or usb power.

Best regards and thanks for your help.

Hi @PHB, Mir’s idle doesn’t disable input events (as noted above, keyboard and mouse are still handled). And it doesn’t have control of USB power.

What it does do is turn the screen off (DPMS mode “Off”), after which the screens I’ve tested do not generate any touch events.

Same hardware,

With X11 it’s ok

on xinitrc : xset dpms 30 60 120

Touch screen wake up …

with ubuntuframe NOK


never wake up on touch screen

Hardware :

A pi4 
ViewSonic screen
Hdmi - usb 
/dev/input/event6:      Weida Hi-Tech                CoolTouchR System

What can i do for help you to debug/test ?

One thing you could do is confirm my understanding of dpms modes:

  1. xset dpms force off
  2. xset dpms force standby
  3. xset dpms force suspend

What Mir does should be equivalent to xset dpms force off and I don’t think that there a meaningful distinction from standby or suspend (except on CRT displays)

All mode function on X11…

  1. xset dpms force off → Work / touch OK
  2. xset dpms force standby → Work / touch OK
  3. xset dpms force suspend → Work / touch OK

Thanks! That proves there’s no distinction between these DPMS modes. So, Mir must be doing something different to Xorg.

1 Like

I’ve raised this as a Mir issue