FreeBSD Device Drivers

Implementing an Interrupt Handler

Example 8-1 is a contrived Newbus driver designed to demonstrate interrupt handlers. Example 8-1 sets up an interrupt handler on the parallel port; on read, it sleeps until it receives an interrupt.

Note

Take a quick look at this code and try to discern some of its structure. If you don’t understand all of it, don’t worry; an explanation follows.

Example 8-1. pint.c

#include <sys/param.h> #include <sys/module.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/conf.h> #include <sys/uio.h> #include <sys/bus.h> #include <sys/malloc.h> #include <machine/bus.h> #include <sys/rman.h> #include <machine/resource.h> #include <dev/ppbus/ppbconf.h> #include "ppbus_if.h" #include <dev/ppbus/ppbio.h> #define PINT_NAME ...