[MTCD Software Development] UnsettledSoul:
[MENTION=3025907]Nightjjr[/MENTION]

Thanks for the offer to test stuff. So let's dive in! Check what kernel modul is loaded for the dongle. Install a terminal emulator (I prefer TermOne Plus from F-Droid, choose whatever you prefer though), start that terminal emulator, plop the dongle in, wait a few seconds, type "dmesg" in the terminal and copy the messages regarding the device. Currently I sit at my desktop but it should look something like this:

3G-stick using option Kernelmodule as driver

[476809.077443] usb 2-10.1.3: new high-speed USB device number 19 using xhci_hcd
[476809.188713] usb 2-10.1.3: New USB device found, idVendor=12d1, idProduct=1003, bcdDevice= 0.00
[476809.188718] usb 2-10.1.3: New USB device strings: Mfr=2, Product=1, SerialNumber=0
[476809.188721] usb 2-10.1.3: Product: HUAWEI Mobile
[476809.188724] usb 2-10.1.3: Manufacturer: HUAWEI Technology
[476809.194521] usb-storage 2-10.1.3:1.0: USB Mass Storage device detected
[476809.195673] scsi host6: usb-storage 2-10.1.3:1.0
[476809.365564] usb 2-10.1.3: USB disconnect, device number 19
[476816.757514] usb 2-10.1.3: new high-speed USB device number 20 using xhci_hcd
[476816.868848] usb 2-10.1.3: New USB device found, idVendor=12d1, idProduct=1003, bcdDevice= 0.00
[476816.868851] usb 2-10.1.3: New USB device strings: Mfr=2, Product=1, SerialNumber=0
[476816.868853] usb 2-10.1.3: Product: HUAWEI Mobile
[476816.868854] usb 2-10.1.3: Manufacturer: HUAWEI Technology
[476816.875903] usb-storage 2-10.1.3:1.0: USB Mass Storage device detected
[476816.889889] option 2-10.1.3:1.0: GSM modem (1-port) converter detected
[476816.890002] usb 2-10.1.3: GSM modem (1-port) converter now attached to ttyUSB0
[476816.890108] usb-storage 2-10.1.3:1.1: USB Mass Storage device detected
[476816.905580] option 2-10.1.3:1.1: GSM modem (1-port) converter detected
[476816.905687] usb 2-10.1.3: GSM modem (1-port) converter now attached to ttyUSB1
[476816.905759] usb-storage 2-10.1.3:1.2: USB Mass Storage device detected
[476816.906236] scsi host6: usb-storage 2-10.1.3:1.2
[476816.906412] usb-storage 2-10.1.3:1.3: USB Mass Storage device detected
[476816.907221] scsi host7: usb-storage 2-10.1.3:1.3
[476817.940998] scsi 7:0:0:0: Direct-Access HUAWEI MMC Storage 2.31 PQ: 0 ANSI: 2
[476817.941399] sd 7:0:0:0: Attached scsi generic sg4 type 0
[476817.943029] scsi 6:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2
[476817.957132] sr 6:0:0:0: [sr1] scsi-1 drive
[476817.965130] sd 7:0:0:0: [sdd] Attached SCSI removable disk
[476817.973864] sr 6:0:0:0: Attached scsi CD-ROM sr1
[476817.973961] sr 6:0:0:0: Attached scsi generic sg5 type 5

See

"option" as the driver and "ttyUSB0" as the device node it creates on the Android / Linux side. And note what the operating system sees it as, a "GSM modem".

Now for another dongle. Used / seen as an ethernet device

[477302.645340] usb 2-10.1.4: new high-speed USB device number 21 using xhci_hcd
[477302.746302] usb 2-10.1.4: New USB device found, idVendor=12d1, idProduct=1f01, bcdDevice= 1.02
[477302.746306] usb 2-10.1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[477302.746307] usb 2-10.1.4: Product: HUAWEI Mobile
[477302.746309] usb 2-10.1.4: Manufacturer: HUAWEI
[477302.746311] usb 2-10.1.4: SerialNumber: FFFFFFFFFFFFFFFF
[477302.752354] usb-storage 2-10.1.4:1.0: USB Mass Storage device detected
[477302.752571] scsi host6: usb-storage 2-10.1.4:1.0
[477303.446083] usb 2-10.1.4: USB disconnect, device number 21
[477303.705359] usb 2-10.1.4: new high-speed USB device number 22 using xhci_hcd
[477303.806443] usb 2-10.1.4: New USB device found, idVendor=12d1, idProduct=14dc, bcdDevice= 1.02
[477303.806446] usb 2-10.1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[477303.806448] usb 2-10.1.4: Product: HUAWEI Mobile
[477303.806449] usb 2-10.1.4: Manufacturer: HUAWEI
[477303.913679] cdc_ether 2-10.1.4:1.0 eth0: register 'cdc_ether' at usb-0000:00:14.0-10.1.4, CDC Ethernet Device, 00:1e:10:1f:00:00
[477303.914265] usb-storage 2-10.1.4:1.2: USB Mass Storage device detected
[477303.915273] scsi host6: usb-storage 2-10.1.4:1.2
[477303.927276] cdc_ether 2-10.1.4:1.0 enx001e101f0000: renamed from eth0
[477304.933957] scsi 6:0:0:0: Direct-Access HUAWEI TF CARD Storage 2.31 PQ: 0 ANSI: 2
[477304.935102] sd 6:0:0:0: Attached scsi generic sg4 type 0
[477304.990921] sd 6:0:0:0: [sdd] Attached SCSI removable disk

See

cdc_ether is the Kernelmodule used, basically a ethernet-driver, and at least here on my desktop system it is renamed afterwards. I doubt android does something similar.

Bottom line I need a device registering on the android side as a "GSM modem" via a serial line (ttyUSB0/1 here), whatever driver it uses.