built-in.o: undefined reference to `s3c2410_iotiming_get' arch/arm/mach-s3c2410/built-in.o: undefined reference to `s3c2410_iotiming_set' arch/arm/mach-s3c2410/built-in.o: undefined reference to `s3c2410_iotiming_calc' Signed-off-by: Ben Dooks