11.3.0 build 8 is not dimming, powering off the screen backlight on XO-1

[garycmartin]

11.3.0 build 8 (or 7) is not dimming, or powering off the screen backlight on an XO-1 during idling. The screen backlight is on all the time vs. the XO1.75 behaviour that dims after a few moments of being left alone and then soon powers off the backlight.

[garycmartin]

Re-testing in 11.3.0 build os882, the XO-1 is still not powering off or dimming the screen backlight when idle - this is a regression from previous olpc official releases (11.2.0).

[pgf]

if someone could attach a powerd.trace file, obtained after "powerd-config =trace-debug", it would be helpful. do some keyboard activity just after enabling trace-debug, then don't touch the laptop again for at least 5 minutes. then save a copy of the log.

[garycmartin]

Log from XO-1

[garycmartin]

Log taken from xo-1.75 at the same time (waited for its backlight to power off to take the logs)

[garycmartin]

Replying to pgf:

if someone could attach a powerd.trace file, obtained after "powerd-config =trace-debug", it would be helpful. do some keyboard activity just after enabling trace-debug, then don't touch the laptop again for at least 5 minutes. then save a copy of the log.

Logs attached, I did an XO-1.75 and XO-1 at the same time for comparison and waited for the 1.75 to power off its back light (takes a little longer than 5min).

[dsd]

The XO-1 screen blanking power saving was disabled by http://dev.laptop.org/git/projects/olpc-utils/commit/?id=78cda69a7e9b41d331426d266bde45d261729047

[pgf]

i'm confused by this. historically XO-1 has had hooks in the X server which made DPMS work correctly. but we disabled it in any case, so that powerd had full control of blanking.

i agree that martin's patch seems to be introducing the disable of DPMS, but powerd should be doing the right thing in any case. (and the log that gary attached looks like it's working correctly.)

[dsd]

DPMS on XO-1 has been enabled in recent releases (10.x/11.x at least). I agree that giving powerd control of this is a nicer solution, but it's not working for whatever reason.

As time is too short to diagnose the powerd issue, we're going to re-enable XO-1 DPMS for 11.3.0 so that we don't ship a release which leaves the screen on. This is not perfect but matches the behaviour of 11.2.0. We can then diagnose the powerd issue for future releases.

[dsd]

XO-1 DPMS re-enabled in olpc-utils-1.3.7

#11364 filed for the powerd fix.

[pgf]

the behavior, and the supplied logfile, are consistent with power management being disabled from the control panel (i.e., /etc/powerd/flags/inhibit-suspend is present). i understand that this is the default behavior, since power management is disabled on XO-1 releases. but i thought it had been the default for some time, so i don't understand the "regression" aspect of this bug.

[dsd]

test in 11.3.0 candidate build 883

[dsd]

test case: boot XO-1, leave on for 30 minutes without using it, check screen blanks after a while

[godiard]

working on os883