BG96 Linux NetworkManager ModemManager

IoT Modules LPWA Module
1

Hi,

we have a custom hardware with BG96 module. The module is recognized in Linux, lsusb shows:
Bus 001 Device 003: ID 2c7c:0296 Quectel Wireless Solutions Co., Ltd. BG96 CAT-M1/NB-IoT modem

i configure connection with

nmcli c add type gsm ifname cdc-wdm0 con-name gsm apn XX
nmcli c up gsm

and get a static ip
ifconfig wwan0

wwan0     Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.193.70.110  P-t-P:10.193.70.110  Mask:255.255.255.252
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:700 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:36593 (35.7 KiB)

But I am not able to get online, no ping is working.

I am able to setup connection successfully with qmcli and udhcpc. But I have to use NetworkManager as this is integrated in our configuration system.

Any hint how to get NetworkManager to work with BG96?

Thanks in advance and best regards
Ruben

2

I doubt this has anything to do with the modem.
Have you checked your routing?

3

Yes, routing looks fine. It’s similar if I add a WiFi connection.
Difference I saw is if using network manager device is in raw ip mode, if starting qmicli device is in 802.3 mode. Any idea if this can cause the problem?

4

to be more clear: ifconfig wwan0 looks like this if I start connection with qmicli

wwan0     Link encap:Ethernet  HWaddr 22:C6:DF:19:6C:7D  
          inet addr:10.193.190.189  Bcast:10.193.190.191  Mask:255.255.255.252
          inet6 addr: fe80::20c6:dfff:fe19:6c7d/64 Scope:Link
          UP BROADCAST RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:14 errors:0 dropped:0 overruns:0 frame:0
          TX packets:67 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:3230 (3.1 KiB)  TX bytes:12598 (12.3 KiB)
5

I don’t think the modem can do both modes, I guess only one of the tools is working properly [with this modem].

6

I don’t use both tools in parallel. During hardware bringup we used qmicli to validate hw function and it worked. Now we decided to go with networkmanager which is not working. If I use networkmanager the qmicli script is disabled, only networkmanager and modemmanager are running

7

That is obvious, no need to explain. I was talking about the modem, not the tools - from my point of view, if it supports, say, 802.3 mode, it will not support other mode(s). I would check the cause with modemmanager.

8

ok, thanks. do you have any idea how to configure modemmanager to use raw-ip or 802.3 mode?

9

No idea, sorry. Uninstalled it years ago.

10

What is your recommendation to configure BG96 from linux?

11

I would just use qmicli with some shell scripting around. It looks like you already have it.

12

yes, nearly. systemd integration is missing. And I am not sure about reconnection handling

13

I am one step further. I checked the logs of ModemManager and saw that the BG96 module reports that it has raw-ip data format. ModemManager then changes to raw-ip which is not working.
Any idea why the bg96 reports raw-ip?

ModemManager[377]: <debug> [946698157.433803] Querying device data format...
ModemManager[377]: [/dev/cdc-wdm0] sent message...
<<<<<< RAW:
<<<<<<   length = 13
<<<<<<   data   = 01:0C:00:00:1A:01:00:01:00:21:00:00:00
ModemManager[377]: [/dev/cdc-wdm0] sent generic request (translated)...
<<<<<< QMUX:
<<<<<<   length  = 12
<<<<<<   flags   = 0x00
<<<<<<   service = "wda"
<<<<<<   client  = 1
<<<<<< QMI:
<<<<<<   flags       = "none"
<<<<<<   transaction = 1
<<<<<<   tlv_length  = 0
<<<<<<   message     = "Get Data Format" (0x0021)
ModemManager[377]: [/dev/cdc-wdm0] received message...
<<<<<< RAW:
<<<<<<   length = 91
<<<<<<   data   = 01:5A:00:80:1A:01:02:01:00:21:00:4E:00:02:04:00:00:00:00:00:10:01:00:00:11:04:00:02:00:00:00:12:04:00:00:00:00:00:13:04:00:00:00:00:00:14:04:00:00:00:00:00:15:04:00:00:00:00:00:16:04:00:00:00:00:00:17:04:00:10:00:00:00:18:04:00:00:10:00:00:1A:04:00:00:00:00:00:1B:01:00:00
ModemManager[377]: [/dev/cdc-wdm0] received generic response (translated)...
<<<<<< QMUX:
<<<<<<   length  = 90
<<<<<<   flags   = 0x80
<<<<<<   service = "wda"
<<<<<<   client  = 1
<<<<<< QMI:
<<<<<<   flags       = "response"
<<<<<<   transaction = 1
<<<<<<   tlv_length  = 78
<<<<<<   message     = "Get Data Format" (0x0021)
<<<<<< TLV:
<<<<<<   type       = "Result" (0x02)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = SUCCESS
<<<<<< TLV:
<<<<<<   type       = "QoS Format" (0x10)
<<<<<<   length     = 1
<<<<<<   value      = 00
<<<<<<   translated = no
<<<<<< TLV:
<<<<<<   type       = "Link Layer Protocol" (0x11)
<<<<<<   length     = 4
<<<<<<   value      = 02:00:00:00
<<<<<<   translated = raw-ip
<<<<<< TLV:
<<<<<<   type       = "Uplink Data Aggregation Protocol" (0x12)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = disabled
<<<<<< TLV:
<<<<<<   type       = "Downlink Data Aggregation Protocol" (0x13)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = disabled
<<<<<< TLV:
<<<<<<   type       = "NDP Signature" (0x14)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = 0
<<<<<< TLV:
<<<<<<   type       = "Uplink Data Aggregation Max Size" (0x15)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = 0
<<<<<< TLV:
<<<<<<   type       = "Downlink Data Aggregation Max Size" (0x16)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = 0
<<<<<< TLV:
<<<<<<   type   = 0x17
<<<<<<   length = 4
<<<<<<   value  = 10:00:00:00
<<<<<< TLV:
<<<<<<   type   = 0x18
<<<<<<   length = 4
<<<<<<   value  = 00:10:00:00
<<<<<< TLV:
<<<<<<   type   = 0x1a
<<<<<<   length = 4
<<<<<<   value  = 00:00:00:00
<<<<<< TLV:
<<<<<<   type   = 0x1b
<<<<<<   length = 1
<<<<<<   value  = 00
ModemManager[377]: <debug> [946698157.438634] Checking data format: kernel 802-3, device raw-ip
ModemManager[377]: <debug> [946698157.438713] Updating kernel data format: raw-ip
14

Found the proplem. Our kernel had some kernel patches which are recommended in another documentation from quectel. When I removed the patch everything works fine. It looks like this kernel patch is not compatible with modemmanager

1 Like
15

Hi ruben ,
I also faced same problem . how it solved.

16

Hi,

Could you precise the patche you removed to have it work?