[krillin] Wi-Fi toggle disappears from menu when Wi-Fi disabled

[Tony Espy]

Device/Image: krillin / rtm #44.

Krillin's Wi-Fi driver has a broken rfkill implementation. As such, urfkill has been updated to allow control over Wi-Fi power via libhybris.

When this mechanism is used to disable Wi-Fi on krillin, the Wi-Fi driver is unloaded as a result, with the corresponding system/NM devices going away as well. This causes the Wi-Fi enable/disable toggle to disappear from the indicator menu, making it impossible to re-enable Wi-Fi.

[Tony Espy (awe)]

Here's a screenshot after Wi-Fi has been disabled.

[Tony Espy (awe)]

Here's a test package with the latest urfkill changes. It's required to reproduce this bug along with the following instructions:

1. Make your image writable
2. Add the following pre-start script to the urfkill upstart job ( this will live in the device tarball when released ):

pre-start script
  setprop urfkill.hybris.wlan 1
end script

3. Disable the Android wlan status script run on boot:

- - adb reboot recovery
 - adb shell

 # mkdir /mnt
 # mount /dev/block/mmcblk0p6 /mnt
 # mkdir /mnt2
 # mount /mnt/var/lib/lxc/android/system.img /mnt2
 # cd bin

 # delete or comment-out the 'setprop' command ( or just remove the file )
   in set_wlan_driver_status.sh

 # cd
 # umount /mnt2
 # umount /mnt
# sync

Note, you may get errors when trying to unmount /mnt. If this happens to me, I just make sure to sync, exit and reboot using adb.

[Jussi Pakkanen (jpakkane)]

I did this and it works in that the toggle button does not disappear. Toggling it off and on makes wifi go off and on. Toggling it again makes the wifi go off and _not_ come back.

This might be partially triggered by the device going to sleep (blanking the screen) or not. It's not 100% clear.

[Tony Espy (awe)]

@Jussi

Please include device/image specifics when reporting test results. That said, thanks for the report. I did some more investigation on this and it appears that in certain cases, this does work ( ie. the UI control doesn't disappear ).

For instance with a freshly flashed RTM/#49 installed ( and all the requisite Wi-Fi changes on the device side ), and 1 SIM (T-Mobile) with data disabled due to lack of credit, when I toggle airplane mode on from the menu, the toggle stays visible. If I insert a second SIM (AT&T) with a working data connection, I'm able to make the toggle disappear.

I discussed with Antti online, and he posits that this is because in some cases the indicator missed the device-removed notification, and if so, the toggle will still render.

[Tony Espy (awe)]

Note there are two ERRORS in the manual instructions detailed in comment #2 for modifying the Android container.

First after running the mount command for /mnt2, you can't cd directly to /bin. Instead: 'cd /mnt2/bin'.

Second, do NOT delete the wlan status script, instead comment out the sleep and setprop commands in the script so it looks like this:

root@ubuntu-phablet:/system/bin# cat set_wlan_driver_status.sh
#!/system/bin/sh

#sleep 2
#/system/bin/setprop wlan.driver.status ok