Suspend fails on manta

[Sergio Schvezov]

Build=20130628 flipped
Hardware=manta

The device doesn't fully go to sleep, I took the precautions of:
- not having a cable plugged in.
- making sure the network was down (just in case).

Touching the display turns the screen back on after it is shutdown.

I tried to check the wakelocks but it seems that /proc/wakelocks does not exist in manta. There seems to be a kernel config diff from maguro which does:

On manta:
root@ubuntu-phablet:/# zgrep -i wakelock /proc/config.gz
CONFIG_HAS_WAKELOCK=y
CONFIG_PM_WAKELOCKS=y
# CONFIG_PM_WAKELOCKS_GC is not set
CONFIG_PM_WAKELOCKS_LIMIT=0
CONFIG_USB_OTG_WAKELOCK=y
CONFIG_WAKELOCK=y

On maguro:
sergiusens@rivendell:~/projects/click/trunk$ adb shell zgrep -i wakelock /proc/config.gz
CONFIG_HAS_WAKELOCK=y
CONFIG_USB_OTG_WAKELOCK=y
CONFIG_USER_WAKELOCK=y
CONFIG_WAKELOCK=y
CONFIG_WAKELOCK_STAT=y

[Seth Forshee (sforshee)]

The wakelock implementation between manta and maguro is completely different: manta uses the newer upstream "autosleep" implementation, and maguro is using the older Android implementation. As a result, the difference in the configs probably doesn't tell us much.

Can you attach your /var/log/kern.log?

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1195855

[Seth Forshee (sforshee)]

Unfortunately the kernel log isn't telling us much about what's going on. To help figure out blocked suspend problems on manta, rather than grabbing /proc/wakelocks you'll need to grab the output of two different files.

/sys/power/wake_lock will print out any active usersapce wake locks. /sys/kernel/debug/wakeup_sources provides a lot of information, including which in-kernel wakeup sources are "active" (an active wake-up source blocks suspend, and this is the mainline analog of in-kernel wake locks). If you capture both of these files when you're in that state I should be able to deduce who is keeping the device from suspending.