devices_SRC += devices/rtc.c # Real-time clock.
devices_SRC += devices/shutdown.c # Reboot and power off.
devices_SRC += devices/speaker.c # PC speaker.
+devices_SRC += devices/pci.c # PCI bus.
+devices_SRC += devices/usb.c # USB layer.
+devices_SRC += devices/usb_uhci.c # UHCI device.
+devices_SRC += devices/usb_ehci.c # EHCI device.
+devices_SRC += devices/usb_storage.c # USB mass storage class driver.
+devices_SRC += devices/usb_hub.c # USB hub class driver.
# Library code shared between kernel and user programs.
lib_SRC = lib/debug.c # Debug helpers.