[Arm-dev] Centos on RPI: driver/module for using serial USB

Hello,

I am using Centos (both Centos 6 and 7) on a Raspberry PI. I am trying 
to connect an AD-converter board
to it with USB. (Future Technology Devices International, Ltd FT232 
USB-Serial (UART) IC)

So I'd probably need some kernel module/driver.  (I have the src for the 
driver, ftdi_sio.
I installed the kernel-headers, but the version of it seems different 
from the kernel?

gcc -Wall -D__KERNEL__ -DMODULE -I/lib/modules/3.18.14-v7+/build/include 
-I/usr/src/linux-3.18.14-v7+/drivers/usb/serial/ -O   -c -o ftdi_sio.o 
ftdi_sio.c
ftdi_sio.c:253:24: fatal error: linux/init.h: No such file or directory
  #include <linux/init.h>

[xxxx at rpi2-1 ftdi_sio]# find / -name "init.h"
/usr/src/kernels/4.2.0-0.rc2.git0.1.centos.el7.armv7hl/include/linux/init.h
/usr/src/kernels/4.2.0-0.rc2.git0.1.centos.el7.armv7hl/include/config/omap2/dss/init.h
/usr/src/kernels/4.2.0-0.rc2.git0.1.centos.el7.armv7hl/include/config/debug/memory/init.h
/usr/include/mysql/private/init.h

Is there a driver, or kernel module, available that I can just use?  If 
not, how to compile the src of that driver?

thanks,

Ron