Registering an Interrupt Handler

The following functions, declared in <sys/bus.h>, register or tear down an interrupt handler:

#include <sys/param.h>
#include <sys/bus.h>

int
bus_setup_intr(device_t dev, struct resource *r, int flags,
    driver_filter_t filter, driver_intr_t ithread, void *arg,
    void **cookiep);

int
bus_teardown_intr(device_t dev, struct resource *r, void *cookiep);

The bus_setup_intr function registers an interrupt handler with an IRQ. This IRQ must be allocated beforehand with bus_alloc_resource, as described in Hardware Resource Management in Don’t Panic.

The bus_setup_intr function is normally called during device_attach. The arguments for this function are described in the next few paragraphs.

The dev argument is the device whose interrupts are to be handled. This device must have an IRQ.