Comment 11 for bug 1079359

Disregarding the time stamps, the first important different line between the two logs is

modem-manager[4156]: <debug> [1356470691.972650] [mm-modem-base.c:155] mm_modem_base_add_port(): (ttyUSB1) type primary claimed by /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.4

for qcserial.ko, where probing is requested by the "Gobi" plugin of modem-manager according to the log.

With option.ko, the probing is requested by the "Huawei" plugin and it looks as if the correct serial port (/dev/ttyUSB2) was queried, but mm_modem_base_add_port() never gets called.