NetBSD/sys/arch/i386/isa/icu.c.old

/*
 * XXX This is going to go away!  It's still here as an example.
 */

/*
 * This driver is a bit of a hack.  For efficiency reasons, it is not
 * general enough to really be useful in itself.  The only useful
 * purpose in making it separate from the isa driver is to get attach
 * messages, and to check for addressing conflicts in the same way that
 * all other ISA drivers do.
 *
 * There are two minor advantages to making it a separate driver:
 *
 * 1) It allows you to put the slave at a different irq on the master.
 * Putting it at irq 5 might make the priorities do something more
 * reasonable on an average machine.
 *
 * 2) It hides all of the initialization gunk.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include "icureg.h"
#include "icuvar.h"

struct icu_softc {
	struct device icu_dev;
	u_short icu_port;
	u_char icu_irq;
	u_char icu_slaves;
	u_char icu_mask;
};

static int icumatch __P((struct device *, struct cfdata *, void *));
static void icuattach __P((struct device *, struct device *, void *));

struct cfdriver icucd =
{ NULL, "icu", icu_match, icu_attach, DV_DULL, sizeof(struct icu_softc), 0, 0};

extern struct cfdriver isacd;

static int
icu_match(parent, cf, args)
	struct device *parent;
	struct cfdata *cf;
	void *aux;
{
#ifdef DIAGNOSTIC
	struct icu_attach_args *ia = aux;

	switch (cf->cf_unit) {
		case 0:
			if (ia->port != ICU0) {
				printf("%s0: must be at port 0x%x",
				    icucd.cd_name, ICU0);
				return 0;
			}
			break;
		case 1:
			if (ia->port != ICU1) {
				printf("%s1: must be at port 0x%x",
				    icucd.cd_name, ICU1);
				return 0;
			}
			break;
		default:
			return 0;
	}

	if (cf->cf_driver == &isacd) {
		/* master has no irq */
		if (ia->irq != -1) {
			printf("%s%d: irq not allowed\n", icucd.cd_name,
			    cf->cf_unit);
			return 0;
		}
	} else if (cf->cf_driver == &icucd) {
		/* slave must have irq; no wildcarding yet */
		if (ia->irq == -1) {
			printf("%s%d: no irq\n", icucd.cd_name, cf->cf_unit);
			return 0;
		}
		if (ia->irq > 7) {
			printf("%s%d: invalid irq\n", icucd.cf_name,
			    cf->cf_unit);
			return 0;
		}
		/* only one level of nesting allowed */
		if (parent->cf_driver == &icucd) {
			printf("%s%d: multiple nesting\n", icucd.cd_name,
			    cf->cf_unit);
			return 0;
		}
	}
#endif

	return 1;
}

static void
icu_reset(sc)
	struct icu_softc *sc;
{
	/* initialization command words */
	outb(sc->icu_port + 0, 0x11);		/* 1) reset; program device */
	outb(sc->icu_port + 1,
	    ICU_VEC + 8 * sc->icu_dev->cf_unit);/* 2) base interrupt vector */
	outb(sc->icu_port + 1, sc->icu_slaves);	/* 3) slave mask */
	outb(sc->icu_port + 1, 0x01);		/* 4) 8086 mode */
	/* operation control words */
	outb(sc->icu_port + 1, sc->icu_mask);	/* 1) interrupt mask */
	outb(sc->icu_port + 0, 0x0a);		/* 3) return IRR on read */
}

static void
icu_attach(parent, self, aux)
	struct device *parent, *self;
	void *aux;
{
	struct icu_softc *sc = (struct icu_softc *)self, *csc;
	struct icu_attach_args *ia = aux;
	struct cfdata *child;

	sc->icu_port = ia->port;
	sc->icu_irq = ia->irq;
	sc->icu_slaves = 0;
	sc->icu_mask = 0xff;

	printf("\n");
	while (1) {
		child = config_search(NULL, self, NULL);
		if (!child)
			break;
		config_attach(self, child, NULL, NULL);
		csc = (struct icu_softc *)child->cf_aux;
#ifdef DIAGNOSTIC
		if (child->cf_driver != &icucd) {
			printf("%s%d: child %s%d is not an %s\n",
			    self->cf_driver->cd_name, self->cf_unit,
			    child->cf_driver->cd_name, child->cf_unit,
			    self->cf_driver->cd_name);
			continue;
		}
#endif
		if (csc->icu_irq != -1)
			sc->icu_slaves |= 1 << csc->icu_irq;
	}

	icu_reset(sc);
}