compile gpio-event in /root/build/linux-omap-3.5/drivers/gpio-event/app using edited Makefile;
insmod /root/build/linux-omap-3.5/drivers/gpio-event/module/gpio-event-drv.ko;
/root/build/linux-omap-3.5/drivers/gpio-event/app/gpio-event 145:f:20 146:f:20;
monitor button presses via 'cat /dev/gpio-event', format is 'pin edge timestamp (from gettimeofday function)'