Firmware load of athn-ar9271 fails

[IdOp]

I've installed OpenBSD 5.3 release onto two machines: the laptop (amd64) and main "desktop" (i386). dmesgs for each are attached to this post.

On each machine I have the same trouble with a USB wireless N adapter: the firmware won't load. The adapter is a NETGEAR WNA1100, based on Atheros chip. Excerpted from one of the dmesgs are the following lines:

athn0 at uhub0 port 2 "NETGEAR WNA WNA1100" rev 2.00/1.08 addr 2
...
athn0: failed loadfirmware of file athn-ar9271 (error 2)
athn0: could not load firmware

The firmware package athn-firmware-1.1p0 was installed using fw_update(1). I also tried an older package athn-firmware-1.1, with the same result (not surprising since the firmware file athn-ar9271 is the same in the two versions of the package).

The man page for the loadfirmware(9) function says it returns an errno(2) code on failure, and errno code 2 is "No such file or directory". Well the files seem to be there:

-r--r--r-- 1 root bin 70624 Jun 16  2011 /etc/firmware/athn-ar7010
-r--r--r-- 1 root bin 70624 Jun 16  2011 /etc/firmware/athn-ar7010-11
-r--r--r-- 1 root bin 51280 Jun 16  2011 /etc/firmware/athn-ar9271
-r--r--r-- 1 root bin  2221 Jun 16  2011 /etc/firmware/athn-license

I also tried replacing athn-ar9271 with the firmware file from Linux, htc_9271.fw; same result, it wouldn't load. (The adapter works under Linux.)

Another data point: when I first got the adapter (1-2 years ago), I tried it under OpenBSD on another machine, and it did work then. So, there was at that time no problem loading the firmware for it.

I tried google-ing the error message above, but didn't find anything useful.

I wanted to try loading the firmware manually by writing a simple C wrapper for loadfirmware(9), to see what happens, but the man page doesn't say what library to link it with.

Any suggestions for how to proceed? Thanks!