Hi all.
It looks like something broke with 15.05. My USB 3G dongle doesn't work any more!
The base system is "TP-Link TL-WDR4900 v1" running "OpenWrt Chaos Calmer 15.05 / LuCI (git-15.248.30277-3836b45)".
The USB dongle is a "1ee8:0013" that is "ONDA COMMUNICATION MW833UP".
It's working with other Linux (not OpenWRT) boxes.

I (think) installed all it's needed (and maybe more):

kmod-usb-acm
kmod-usb-core
kmod-usb-net
kmod-usb-net-cdc-mbim
kmod-usb-net-cdc-ncm
kmod-usb-net-qmi-wwan
kmod-usb-ohci
kmod-usb-serial
kmod-usb-serial-option
kmod-usb-serial-wwan
kmod-usb-wdm
kmod-usb2
kmod-usb2-fsl /* my unit CPU is FreeScale! */
luci-proto-3g
usbutils
comgt
comgt-ncm /* maybe useless */
usb-modeswitch

When I insert the dongle it looks like it's working as the ttyACM0 device pops up in the /dev directory.

Wed Feb 10 11:04:04 2016 kern.info kernel: [34058.684172] usb 1-1.2: USB disconnect, device number 4
Wed Feb 10 11:13:44 2016 kern.info kernel: [34638.204978] usb 1-1.2: new high-speed USB device number 5 using fsl-ehci
Wed Feb 10 11:13:44 2016 kern.info kernel: [34638.518263] usb 1-1.2: USB disconnect, device number 5
Wed Feb 10 11:13:49 2016 kern.info kernel: [34643.580840] usb 1-1.2: new high-speed USB device number 6 using fsl-ehci
Wed Feb 10 11:13:49 2016 kern.info kernel: [34643.679535] cdc_acm 1-1.2:1.0: ttyACM0: USB ACM device

The LuCI 3G module allows me to configure it but nothing more than that.
The 3GWWAN inteface never comes up, despite all my clicking to the  "connect" button in Network-->Interfaces-->3GWWAN

The difficult part is troubleshooting.
I don't know how to get logs from the whole software stack in order to understand where the failure is.

Any hint?

TIA.

(Last edited by uqbar on 10 Feb 2016, 11:29)