USB modem, no /dev/ttyUSB

[ahmed-anas]

Hey guys,
I'm trying to get my usb dongle to work with TP-Link mr-3420v5 flashed with openwrt.

According to the guide here (https://openwrt.org/docs/guide-user/network/wan/wwan/3gdongle), I should see the following dmesg

USB Serial support registered for generic
usbserial_generic 1-1:1.0: generic converter detected
USB Serial support registered for generic
usbserial_generic 1-1:1.0: generic converter detected
usb 1-1: generic converter now attached to ttyUSB0
usbserial_generic 1-1:1.1: generic converter detected
usb 1-1: generic converter now attached to ttyUSB1

or this

scsi1 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 4
usb-storage: waiting for device to settle before scanning
scsi 1:0:0:0: CD-ROM            Novatel  Mass Storage     2.31 PQ: 0 ANSI: 0
scsi 1:0:0:0: Attached scsi generic sg1 type 5
usb-storage: device scan complete

however I get neither. And there is no /dev/ttyUSB

I do however see my device when I run cat /sys/kernel/debug/usb/devices

T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  3 Spd=480  MxCh= 0
D:  Ver= 2.10 Cls=02(comm.) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=12d1 ProdID=14db Rev= 1.02
S:  Manufacturer=HUAWEI_MOBILE
S:  Product=HUAWEI_MOBILE
C:* #Ifs= 2 Cfg#= 1 Atr=80 MxPwr=  2mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=(none)
E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=2ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=06 Prot=00 Driver=(none)
E:  Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms

Any ideas? Thanks/

[Per]

Have you installed the drivers? Try
opkg install kmod-usb-net-rndis usb-modeswitch
and if it still doesn't work then look at the links just above Preparations.

[ahmed-anas]

Is there any way to identify what protocol your usb modem uses? By connecting the modem to the PC for example?

[Per]

Not that I know of, but I haven't tried.

[ahmar16]

Some USB sticks use RNDIS now-a-days which basically is a small router kinda device. It provides DHCP service and if you connect it to router/pc it directly provides internet. You dont need to connect it. It will be identified as an Ethernet interface in the router/pc, just like eth0 or eth1 in Openwrt.

Other devices are basically old modems, they get identified through drivers and once identified they can be connected through UMTS/GPRS/EDGE protocol in the router.

Your settings will differ according to the type of device you have. If you have the RNDIS one, you need to install kmod-usb-net-rndis and if you have modem one you need kmod-usb-serial kmod-usb-serial-option kmod-usb-serial-wwan.

[Edit] If you have enough space on your router, try to install all of them. When your device gets identified, create a new interface and assign it UMTS/GPRS/EDGE protocol and see if your modem gets identified in the config. If not then it's probably RNDIS based.

[ahmed-anas]

Thanks.

Small update. I've basically installed all of the drivers I could find (:/) . Now when I plug in my modem and write dmesg I get the following output:

[ 1551.715591] usb 1-1: new high-speed USB device number 5 using ehci-platform
[ 1552.376145] usb 1-1: USB disconnect, device number 5
[ 1552.935676] usb 1-1: new high-speed USB device number 6 using ehci-platform
[ 1553.328811] cdc_ether 1-1:1.0 eth1: register 'cdc_ether' at usb-101c0000.ehci-1, CDC Ethernet Device, 0c:5b:8f:27:9a:64

[ahmar16]

It's RNDIS based device, you will have an extra interface in Interfaces. Just create a new Interface and in physical tab look for a new ethX.