EC25 qmi cdc-wdm0 device not responding

IoT Modules LTE Standard Module
1

Hi,

I’ve got a router with the EC25 LTE modem:
Bus 001 Device 003: ID 2c7c:0125 Quectel Wireless Solutions Co., Ltd. EC25 LTE modem

The router is running OpenWrt 19.07.3 r11063-85e04e9f46 which has 4.14.180 linux kernel.

Modem has the following firmware:
root@OpenWrt:~# socat - /dev/ttyUSB2,crnl
ATI
Quectel
EC25
Revision: EC25EFAR06A06M4G
OK

I’ve enabled ppp & qmi mode with the following over ttyUSB2: AT+QCFG="usbnet",0
This makes the device show up as /dev/cdc-wdm0.
When I try to use uqmi to do anything ie. check for signal strength (uqmi -d /dev/cdc-wdm0 --get-data-status --get-signal-info), the device is totally unresponsive.

How can I troubleshoot this?

2

Looks unrelated to Quectel yet. Try:

uqmi -s -d /dev/cdc-wdm0 --sync
uqmi -s -d /dev/cdc-wdm0 --get-client-id wds
4

The device is not responding to these commands either.

5

Then I would move the modem to another system if possible and test there.
If you can connect it to a regular Linux host you can test with qmicli.
Alternatively you can switch the modem to MBIM and test it in that mode.

6

Was not able to get QMI to work, but when switched to MBIM it worked. I guess that’ll be the solution to this problem… Use MBIM.

7

Try this before using any qmi commands:

cat </tmp/init.chat
ABORT “BUSY”
ABORT “NO CARRIER”
ABORT “VOICE”
ABORT “NO DIALTONE”
ABORT “NO DIAL TONE”
ABORT “NO ANSWER”
ABORT “DELAYED”
REPORT CONNECT
ECHO OFF
“” “AT”
“OK” “ATZ”
“OK” “AT&F”
“OK” “AT+CFUN=0”
“OK” “AT+CFUN=1”
“OK” “AT+CFUN=4”
“OK” “AT+CGDCONT=1,“IP”,”","""
“OK” “AT+CFUN=1”
EOF

chat -t 1 -f /tmp/init.chat < “/dev/ttyUSB2” > “/dev/ttyUSB2”

8

Thanks for your sharing. We can close this topic now. If you have any other question, you can create a new one. Thanks!