Hi aloniv!
I created a ath9k_htc linux driver a long time ago when the firmware source
code was first released to public as FLOSS (Free/Libre and Open Source
Software). Since then, the firmware was whitelisted in the Toutatis mainline
kernel, thus making this installer no longer necessary to be used.
One of the scripts within the package is called build-fw.sh, which you can
use to build the desired firmware files from the latest source code
available. Building depends on some extra packages that are necessary to be
installed, and because of that, I recommend you to run the script within the
LiveCD environment, either using some virtualization software, or by booting
the CD/DVD directly.
Just for curiosity, can you tell me what device you're using?
P.S.: You can experience that the script refuse to work properly for the
first time you execute it. That happens because wget (for some unknown
reason) cannot connect and download the source code from the Internet.
Running the script for the second time worked for me.