Once you have your device driver written, the next task is to have it compiled and installed into a bootable kernel. This is actually quite a straightforward task, performed in a few simple steps as follows:

• The first job is to copy your driver.c file and any associated driver.h file into the directory which contains the source code for character device drivers. This is in drivers/char under the top level Linux source directory.
  
  
• Next, you should add a call to your driver's init() routine to the end of the function chrdev_init() in the file drivers/char/mem.c.
  
  
• Now edit the Makefile in the drivers/char directory and add your driver.o name to the end of the definition for OBJS and your driver.c name to the end of the definition for SRCS.
  
  
• Now change directory to the top level Linux source directory and just build and install your new kernel using the steps described back in the Linux Installation tutorial.

If you use lilo to boot your system, it is a good idea to treat your new kernel as experimental and generate an extra Linux boot section in the lilo.conf (if you use lilo) file so that you can still boot from your old kernel if the new one fails to boot or fails to perform correctly for some reason.

As a general precaution when modifying kernel code, it is always advisable to make a backup of anything on your machine that you do not feel prepared to loose. The chances are that, for most problems, either the new code will just not work or it will cause the kernel to panic. In general, neither of these events will cause any lasting damage to your system, especially if you can reboot your machine from the old kernel. However, in theory, it is possible for bugged kernel code to do absolutely anything, including scrapping data on your hard disk. So, it is always better to be safe than sorry.

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