Information

Mass-storage switch

$ sudo apt-get install usb-modeswitch

Plugin modem again and you should get a bunch of serial ports:

[ 5445.108101] usb 2-2: new high speed USB device number 3 using ehci_hcd
[ 5445.242467] usb 2-2: New USB device found, idVendor=12d1, idProduct=1446
[ 5445.242477] usb 2-2: New USB device strings: Mfr=3, Product=2, SerialNumber=0
[ 5445.242484] usb 2-2: Product: HUAWEI Mobile
[ 5445.242489] usb 2-2: Manufacturer: HUAWEI Technology
[ 5445.244981] scsi7 : usb-storage 2-2:1.0
[ 5445.245515] scsi8 : usb-storage 2-2:1.1
[ 5446.017603] usb 2-2: USB disconnect, device number 3
[ 5450.036132] usb 2-2: new high speed USB device number 4 using ehci_hcd
[ 5450.170725] usb 2-2: New USB device found, idVendor=12d1, idProduct=1436
[ 5450.170736] usb 2-2: New USB device strings: Mfr=4, Product=3, SerialNumber=0
[ 5450.170743] usb 2-2: Product: HUAWEI Mobile
[ 5450.170748] usb 2-2: Manufacturer: HUAWEI Technology
[ 5450.175800] scsi14 : usb-storage 2-2:1.5
[ 5450.176793] scsi15 : usb-storage 2-2:1.6
[ 5450.271164] usbcore: registered new interface driver usbserial
[ 5450.271176] USB Serial support registered for generic
[ 5450.271234] usbcore: registered new interface driver usbserial_generic
[ 5450.271236] usbserial: USB Serial Driver core
[ 5450.296230] cdc_ether 2-2:1.1: wwan0: register 'cdc_ether' at usb-0000:00:1d.7-2, Mobile Broadband Network Device, 02:50:f3:00:00:00
[ 5450.296411] usbcore: registered new interface driver cdc_ether
[ 5450.362679] USB Serial support registered for GSM modem (1-port)
[ 5450.362792] option 2-2:1.0: GSM modem (1-port) converter detected
[ 5450.362908] usb 2-2: GSM modem (1-port) converter now attached to ttyUSB0
[ 5450.362928] option 2-2:1.3: GSM modem (1-port) converter detected
[ 5450.362987] usb 2-2: GSM modem (1-port) converter now attached to ttyUSB1
[ 5450.362997] option 2-2:1.4: GSM modem (1-port) converter detected
[ 5450.363051] usb 2-2: GSM modem (1-port) converter now attached to ttyUSB2
[ 5450.363073] usbcore: registered new interface driver option
[ 5450.363074] option: v0.7.2:USB Driver for GSM modems

Check if voice is enabled

ati
Manufacturer: huawei
Model: E171
Revision: 11.126.85.01.143
IMEI: 354807044078459
+GCAP: +CGSM,+DS,+ES

AT^CVOICE?
^CVOICE:0,8000,16,20