I had to add the following line to /lib/udev/rules.d/77-mm-ericsson-mbm.rules for the Ericsson N5321 WWAN adapter:
ATTRS{idVendor}=="0bdb", ATTRS{idProduct}=="193e", ENV{ID_MM_ERICSSON_MBM}="1"
To be sure what vendor and product ID to use, you should check that first via 'lsusb|grep Ericsson'.
I did not care about GPS yet.