No cdc_mbim driver for Quectel EM06

Which Khadas SBC do you use?

VIM3 PRO

Which system do you use? Android, Ubuntu, OOWOW or others?

Ubuntu

Which version of system do you use? Khadas official images, self built images, or others?

Khadas’ Fenix 1.0.9 Ubuntu 20.04.3

Please describe your issue below:

Can’t configure Quectel modem to a preferred 4G tech nor getting it to response to AT commands.
Quectel support pointed out that the kernel is missing cdc_mbim driver (see the “Driver=(none)” info below).
How do I get the cdc_mbim driver & add it to VIM3?

Post a console log of your issue below:


T:  Bus=01 Lev=02 Prnt=02 Port=02 Cnt=02 Dev#=  3 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=2c7c ProdID=0306 Rev=03.10
S:  Manufacturer=Quectel
S:  Product=EM06-A
S:  SerialNumber=0123456789ABCDEF
C:  #Ifs= 6 Cfg#= 1 Atr=a0 MxPwr=500mA
I:  If#=0x0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=option
I:  If#=0x1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
I:  If#=0x2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
I:  If#=0x3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=option
I:  If#=0x4 Alt= 0 #EPs= 1 Cls=02(commc) Sub=0e Prot=00 **Driver=(none)**
I:  If#=0x5 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=02 **Driver=(none)**

**"Driver=(none)" for interface 4 & 5 there should have had "cdc_mbim" as the driver**

Enable the modules you want.

$ make kernel-config

Save the defconfig.

$ make kernel-saveconfig

Rebuild the kernel package.

$ make kernel-deb

Build image.

$ make

Thanks numbqq for the response.

For someone without any kernel experience, this info … is not helpful. Looks like I’ll need to dig into this info first Build Linux Kernel | Khadas Documentation.

Since Quectel’s EM06 is promoted as part of VIM3’s accessories, why cdc_mbim is not available by default in Khadas linux OS provided?

Could you please tell me what does this modules do? Without this module, the 4G module can also work well. Anyway, we can add this module by default it is necessary.

I’m still learning about cdc_mbim (cdc_mbim - Driver for CDC MBIM Mobile Broadband modems — The Linux Kernel documentation) & MBIM in general…

Basing on Quectel’s support answers, interface 4 & 5 (as mentioned at the start of this query) is needed for the network interface as well as to do direct AT command. They emphasized that “Without the network interface, the system will go back to PPP protocol which is inefficient. And the modem manager will not be able to access MBIM protocol.”

We were hoping to use EM06 directly w/o much fiddling beyond using mmcli (& modemManager). We are currently facing 2 issues.

(1) the global SIM provider couldn’t get the EM06 to response to reboot commands sent over SMS. This is the most important since the modem needs to be able to switch SIM profile out in the field to get a different SIM operator after reboot (the iot device is not easily accessible).

(2) we want our IoT products to use ‘prefer 4G tech’, which can’t be done using just mmcli. Currently, our products oversea (through EM06) pick up UMTS (3G) over 4G LTE (which also available) & had poor roaming SIM problem.

In both cases, Quectel seems to point toward the needs to be able to use AT commands. They also want to know if they could talk to Khadas team.

If you have any suggestions without the needs for the driver, I’m all ears.

Hi numbqq, is it possible for Khadas team to add that cdc_mbim driver to the fenix image (& other future OS builds)?

Hello @quin_tu

Yes, we will add it in next release.

1 Like

Thanks very much, numbqq! That’ll save us for having to make a production image build ourselves for each of your new releases.
May I ask when to expect this next release?

Hi, just following up to know if fenix release v1.1.2 has this cdc_mbim driver?
I went through “GitHub - khadas/fenix: One-stop script set to build Ubuntu/Debian images” commit msgs and don’t see any mentioning. Is there a release notes info page in general?

Thanks!

Yes, it already has this configuration.

That’s great. Thanks.
Will be trying out this OS very soon.