Comment 26 for bug 1493574

While I cannot yet reproduce it I have a germ of a theory. From the logs I see that both Peter and Mathew have autobrightness enabled. I also see that the powerd logic is explicitly setting the brightness to zero seemingly independent of the proximity reading. So perhaps we have a race between proximity, screen on and off, and autobrightness which is confusing powerd into a bad state.

@peter please try turning Adjust brightness automatically to off in the battery indicator and see if you still get the issue.

Mathew's log

Dec 7 09:41:58 ubuntu-phablet powerd[720]: set brightness 55
Dec 7 09:41:58 ubuntu-phablet powerd[720]: light_dev: setting brightness to 55
Dec 7 09:42:00 ubuntu-phablet powerd[720]: light_dev: setting brightness to 15
Dec 7 09:42:03 ubuntu-phablet powerd[720]: light_dev: setting brightness to 0

Peter's log
Mar 8 23:44:58 ubuntu-phablet powerd[757]: set brightness 12
Mar 8 23:44:58 ubuntu-phablet powerd[757]: light_dev: setting brightness to 12
Mar 8 23:44:58 ubuntu-phablet powerd[757]: turn_display_on(0)
Mar 8 23:44:58 ubuntu-phablet powerd[757]: light_dev: setting brightness to 0

Mar 8 23:44:59 ubuntu-phablet powerd[757]: light_dev: setting brightness to 12
Mar 8 23:45:00 ubuntu-phablet powerd[757]: we get signal from :1.40: DisplayPowerStateChange
Mar 8 23:45:00 ubuntu-phablet powerd[757]: Received DisplayPowerStateChange: state=1 flags=2
Mar 8 23:45:00 ubuntu-phablet powerd[757]: set brightness 12
Mar 8 23:45:01 ubuntu-phablet powerd[757]: light_dev: setting brightness to 0

Mar 8 23:45:02 ubuntu-phablet powerd[757]: turn_display_on(0)
Mar 8 23:45:02 ubuntu-phablet powerd[757]: turn_display_on(0)
Mar 8 23:45:02 ubuntu-phablet powerd[757]: light_dev: setting brightness to 0