This kernel module creates the /sys/devices/platform/mts-io enumeration of the features for MTAC GPIO boards. This driver requires the mtac.ko driver loaded first. depmod should take care of this. Documentation for this board is here: http://www.multitech.net/developer/software/mlinux/using-mlinux/mlinux-using-accessory-cards/mtac-gpio-usage/ An init script can look in: /lib/modules/$(uname -r)/extra/mtac_gpiob.ko to find the driver.