From WhitixDoc

Every device driver has a basic layout. First of all, every driver has an initialise function, which sets up some of the device's data structure and usually registers the device with one or more subsystems.

The typical layout of the core of a driver file looks like this:

/* License */
 
#include <init.h>
#include <module.h>
/* Other includes */
 
int DevInit()
{
   /* Init function. */
}
 
DeviceInit(DevInit);