OpenWRT QMI - HL7588 issues


I am trying to bring up a HL7588 chip on OpenWRT QMI. When I bring up the OS I see that ttyACM devices are created, rather than ttyUSB. I am able to successfully connect to ttyACM0 and send AT commands to the chip and get a response. What is not happening is the cdc-wdm0 handle is not created and as a consequence the QMI is not able to communicate with the chip. I have the Sierra Wireless specific drivers loaded, but I must be missing something either in the configuration or the order of the drivers loading.

Is anyone able to give me some guidance in how to proceed?


Hi jaugenstine,
HL7588 is not based on QMI, please check (or configure desired composition) using AT+KUSBCOMP command, refer to AT cmd guide for details:

Per understanding, you can use PPP dialup on ACM interface, or CDC-NCM, or MBIM instead.

Hope it helps.


OK, I have made some progress. I am able to use picocom to activate the wireless modem and retrieve an IP address. Everything is good there. So I moved on to try to bring up the modem on openwrt with cdc-ncm. What I am not seeing happening is I do not see the /dev/cdc-wdm0 being created. Any ideas here?


+KUSBCOMP should show you what interface is enabled, please also check OpenWRT kernel message if it found the interface and load the driver correctly.