Quectel EC25 4G modem QMI mode

Hardware Questions and Recommendations
1

This is my device:
Bus 001 Device 003: ID 2c7c:0125 Quectel Wireless Solutions Co., Ltd. EC25 LTE modem

I have a working cell connection in cdc_ether mode (from dmesg):
[ 18.312512] cdc_ether 1-1.3:1.4 usb0: register 'cdc_ether' at usb-101c0000.ehci-1.3, CDC Ethernet Device, 3a:d8:e2:f5:5b:66

And I also have a working usb serial connection with the modem. So I can do AT commands. Here's the software version:
root@OpenWrt:~# socat - /dev/ttyUSB2,crnl
ATI
Quectel
EC25
Revision: EC25EFAR06A06M4G
OK

I've installed the qmi driver, and it's being loaded at boot:
[ 18.929226] usbcore: registered new interface driver qmi_wwan

But when I check for /dev/cdc-wdm0 device, there's no such device. I belive this is because my modem is not in "qmi mode".

How can I set this modem in qmi mode?

For the reference, here's a documentation for AT commands for this modem: https://itbrainpower.net/downloadables/Quectel_EC25_EC21_AT_Commands_Manual_V1.0.pdf - but unfortunately I don't understand AT commands.

2 
AT+QCFG="usbnet",0

Nothing to do with OpenWrt.

3

Thanks for your reply.
This might not be OpenWrt software related, but it's still related to hardware I use with OpenWrt. I'm on OpenWrt 19.07.3 r11063-85e04e9f46

The command seems to not be sufficient tho, I did get OK when doing AT+QCFG="usbnet",0, but the cdc-wdm0 device did not show up. Even after a reboot.

When I did a second try at AT+QCFG="usbnet",0 and it returned OK as the first time, but when I check it with AT+QCFG="usbnet"? it returns +QCFG: "usbnet",1. Is it possible that I've only got read access over the ttyUSB?

4

Switch it off then on.

5

Thanks! That works.
The cdc-wdm0 device is unresponsive, but that's a problem for an other day.

6

Btw. after googeling "usbnet", i found a list of all the usbnet settings. Will post it here for reference:
AT+QCFG="usbnet",0 - is PPP & QMI (default)
AT+QCFG="usbnet",1 - is ECM.
AT+QCFG="usbnet",2 - is MBIM

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7

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