OpenWRT QMI - HL7588 issues


#1

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?


#2

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:
https://source.sierrawireless.com/resources/airprime/software/airprime_hl7588_at_commands_interface_guide/

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

Hope it helps.
Thx


#3

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?


#4

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