Digitiser still works when phone locked

[Alan Pope 🍺🐧🐱 🦄]

Boot Ubuntu on a Nexus 4
Open music app
Start playing songs
Tap the power button to lock the screen
Swipe in from left or top edge
Tap the power button to unlock the screen
Observe the launcher (left) or indicator (top) have opened, while the screen was 'locked'

Reproduced this on #106 and #111, only happens if you launch music first and play music it seems. Launching music and _not_ playing a song isn't sufficient to trigger this.

Here's a video showing it. https://www.youtube.com/watch?v=0Y_JoVfzDmA

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Victor Thompson (vthompson)]

Not sure if this has to do with the music-app's lifecycle exception or if it's due to media-hub when audio is actively being played.

[Victor Thompson (vthompson)]

I can reproduce this with YouTune playing music. So this shouldn't be due to the music app or its life cycle exception.

[Keith Hammond (keithammond)]

how is the importance of this not critical? This is an extremely important bug!

[Victor Thompson (vthompson)]

I'm not sure when this was fixed, but it no longer happens using image #205.

[Victor Thompson (vthompson)]

My previous recommendation that this was Fixed Released was incorrect. This bug still exists.

[Andrew Hayzen (ahayzen)]

I was suffering from this yesterday, I noted the following behaviour.

After/While running the music the screen still detects input even with it off
After the music had closed music-app was still in powerd [0] and I could interact with any app with the display off
Only a restart of the device resolved the issue.

0 - $ powerd-cli list
powerd-cli: Running as user is not fully supported.
System State Requests:
  Name: com.canonical.Unity.Screen, Owner: :1.11, State: 1
  Name: media-hub-music-playback, Owner: :1.129, State: 1

[Andrew Hayzen (ahayzen)]

Note the above output of powerd-cli was when the music-app was running and not when it was closed (i'm trying to get that to happen again so I can check if the output is the same).

Also if this bugs still exists we need to either change powerd to not fix released or music-app to not invalid otherwise this bug will be lost.

[Jim Hodapp (jhodapp)]

This is an interesting bug because the system state request seen in powerd has to do with keeping the device from going into a deep sleep, but it shouldn't affect the input state of the device because it's not a display wakelock. This might possibly be an issue at a lower layer even under powerd. I'll subscribe rsalveti so he can give his thoughts on this.

One question I have. If you pause the music and then lock the screen manually, does this bug still happen?

[Andrew Hayzen (ahayzen)]

If I pause the music and lock the screen then no input interacts with the screen (as expected) and music-playback is not in powerd-cli list when paused.

[Andrew Hayzen (ahayzen)]

Also note that this can be reproduced by playing music from the local music scope, but not reproduced when playing video in the media player.

[Seth Forshee (sforshee)]

This isn't really a problem with powerd. As far as I know there's no standard interface (and likely as not no interface at all) for telling an input driver to stop sending events other than closing the input device, and powerd can't close the device on behalf of another process. The input stack needs to close the input device (preferably, or else stop listening to events from the touchscreen input device) whenever the screen is off.

[Ricardo Salveti (rsalveti)]

Yeah, the one taking care of screen on/off and input is now mir and system-compositor. The only responsibility powerd has here is not letting the device to suspend when the lock is in place.

[Alberto Aguirre (albaguirre)]

Yes, this needs to be addressed in mir (the next mir release should have a fix for it):

https://bugs.launchpad.net/ubuntu/+source/mir/+bug/1359264