USB WLAN - TP-Link TL-WN821N v2 [Atheros AR9170] - Device cannot be used

[Testlab]

Hello,

unfortunately I can't get my USB WLAN stick to work. I would like to start by briefly describing what I am using and what I have done so far.

I have a freshly installed and updated OPNSense version running in my test lab.

The OPNSense dashboard currently shows the following versions:
   OPNsense 23.7.8-amd64
   FreeBSD 13.2-RELEASE-p5
   OpenSSL 1.1.1w 11 Sep 2023

Various compatible WLAN USB adapters are listed in the FreeBSD 13.2-RELEASE Hardware Notes. I have the version 2 of this adapter -> Qualcomm Atheros Communications TP-Link TL-WN821N v2 802.11n [Atheros AR9170]. According to the hardware notes, the TP-Link TL-WN821N v1, v2 is listed as compatible with the otus driver.

I have created the file /boot/loader.conf.local and inserted the following lines, which may not even be necessary:
   if_otus_load="YES"
   otusfw_main_load="YES"
   otusfw_init_load="YES"

The otusfw* files are already available here via the initial installation, I have not changed them:
   /boot/kernel/otusfw-init.ko
   /boot/kernel/otusfw-main.ko

When the system boots, the following error messages appear when trying to load the otus driver:
   otus0: otus_load_firmware: otusfw_main: error=5
   otus0: otus_attachhook: could not load main firmware
   device_attach: otus0 attach returned 6

Unfortunately I cannot get the WLAN adapter to work and it is not offered for selection in the web console.

Does anyone have any idea how I can track down the problem and how I can solve it?

[Testlab]

The problem has now been solved for me by buying a different USB WLAN stick with a different chipset. This USB WLAN stick uses the run driver and works straight away. I now use the Linksys WUSB600N WLAN stick.