My Lifebook T4215 has five function keys attached to the LCD panel. Those keys need a special driver. This patch is a re-implementation of the apanel Linux driver for OpenBSD. It is applicable to OpenBSD 5.3-current as of April 2013, tested with my T4215 on both i386 and amd64.
Please note this driver uses I2C polling. There is a way to use the keys in a interrupt driven way. A future version might implement that.
To use it, apply the patch and compile a new kernel. If the driver finds a suitable button device, it will attach a keyboard that emits extended F-Key keycodes. In cwm(1), you can use them like this for example: