How to use the EXTRA_FIRMWARE_DIR kernel option?

Question

I am using Gentoo, and I need to load an extra firmware to get my USB Wifi adapter work. I found an EXTRA_FIRMWARE_DIR kernel option, but I do not understand if it is used during compile time only or if it is effective after the new kernel is used. My WiFi adapter chip is Atheros, and according to this page, I have to put the firmware to the right place. On Ubuntu, I found the /lib/firmware directory as it is indicated in that page, but I cannot find that directory on Gentoo.

Answer 1

Take a look at this: http://www.kernel.org/doc/menuconfig/drivers-base-Kconfig.html

In particular:

• EXTRA_FIRMWARE "allows firmware to be built into the kernel, for the cases where the user either cannot or doesn't want to provide it from userspace at runtime"

• EXTRA_FIRMWARE_DIR "controls the directory in which the kernel build system looks for the firmware files listed in the EXTRA_FIRMWARE option. The default is the firmware/ directory in the kernel source tree, but by changing this option you can point it elsewhere, such as the /lib/firmware/ directory or another separate directory containing firmware files".

By the way, as far as getting your wireless card working, have you taken a look at these pages?:

• http://en.gentoo-wiki.com/wiki/TL-WN821N

• http://bugs.gentoo.org/278385