No FN key support in newest kernel releases?

[saviles]

I've been using F7 for over 5 months now.

The last 2 kernel updates 2.6.23.1-21.fc7 and 2.6.23.8-34.fc7, have somehow disabled the use of the FN key on my Dell D520. I have a dual monitor setup and I need the FN+F8 key combo to work to enable the 2nd external monitor.
The last working kernel (which i'm currently using) is 2.6.22.9-91.fc7.

There has been zero changes to my grub.conf and my x.org files. I do not know if i'm missing a config setting or change that has made this key stop working. I've actually submitted a bug report (https://bugzilla.redhat.com/show_bug.cgi?id=378541) but there has been no action on that.

Anyone have any suggestions/ideas?

Thanks.

[HaydnH]

If you install the devel packages for the 2 kernels (one working and the next update to it) you have a .config file in each /usr/src/kernels/{kernel version} path. Running diff on the 2 .configs would tell you what's changed. However, knowing what's changed won't really help unless you fancy recompiling yourself a new kernel.

Have you googled for the brand of the laptop and "linux function keys"?

[saviles]

One of the kernel devels responded to the bug report and suggested the following, which worked:
# echo 1 > /proc/acpi/video/*/DOS

In my particular case, it was
# echo 1 > /proc/acpi/video/VID/DOS

Hope this helps someone else.