Created attachment 973019 [details] 1.4.0 log ModemManager 1.4.0-1.fc21 does not connect: NetworkManager[663]: <warn> (ttyUSB0) failed to connect modem: Cannot recover from a power off (NetworkManager:663): NetworkManager-wwan-CRITICAL **: modem_prepare_result: assertion 'state == NM_DEVICE_STATE_PREPARE' failed If I downgrade to ModemManager-1.1.0-2.git20130913.fc20.i686, then it connects. After connecting I upgrade again to ModemManager-1.4.0-1.fc21.i686, and then it connects too. Modem is ZTE MF628. Logs with 1.4.0 and 1.1.0 versions are attached.
Created attachment 973020 [details] 1.1.0 log
I've checked with other versions. ModemManager-1.3.0-2.fc21.i686.rpm and 1.4.4-1 do not work, version 1.2.0-3 works. So the breakage happened between 1.2.0 and 1.3.0.
I reported upstream - https://bugs.freedesktop.org/show_bug.cgi?id=89368
Created attachment 997108 [details] fix It was fixed upstream. I attach the fix.
Upstream commit - http://cgit.freedesktop.org/ModemManager/ModemManager/commit/?id=6a8fbf917a220416913a5e64a40bd4d26c6448f5
Fixed in ModemManager-1.4.6-1.fc22, so I'm closing this.