I have a laptop running Slackware 12.1.0 with an LCD brightness issue.

The LCD brightness can be perfectly fine set by using the proprietary buttons on the keyboard (Fn + some F-key). However, after the brightness has been set to the level that I want, it will slowly revert back to the lowest possible setting.

This is extremely annoying as it makes the display very dark, and has to be constantly adjusted up again. It seems that this issue does not happen if the computer has not been suspended by ACPI. Thus prior to suspending the system the LCD brightness can be set perfectly fine, and does not revert back. But after suspending and waking up the system again, then this issue happens.

What should I do to resolve this?