xref: /freebsd/sys/dev/smbus/smbus.c (revision 202379af847e82a654964f69aaa3435212732eff)

/*-
 * Copyright (c) 1998, 2001 Nicolas Souchu
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/bus.h>

#include <dev/smbus/smbconf.h>
#include <dev/smbus/smbus.h>

#include "smbus_if.h"
#include "bus_if.h"


/*
 * Autoconfiguration and support routines for System Management bus
 */

/*
 * Device methods
 */
static int smbus_probe(device_t);
static int smbus_attach(device_t);
static int smbus_detach(device_t);

static int smbus_child_location_str(device_t parent, device_t child,
		    char *buf, size_t buflen);
static int smbus_print_child(device_t parent, device_t child);
static void smbus_probe_device(device_t dev, u_char* addr);
static int smbus_read_ivar(device_t parent, device_t child, int which,
		    uintptr_t *result);

static device_method_t smbus_methods[] = {
        /* device interface */
        DEVMETHOD(device_probe,         smbus_probe),
        DEVMETHOD(device_attach,        smbus_attach),
        DEVMETHOD(device_detach,        smbus_detach),

	/* bus interface */
	DEVMETHOD(bus_add_child,	bus_generic_add_child),
	DEVMETHOD(bus_child_location_str, smbus_child_location_str),
	DEVMETHOD(bus_driver_added,	bus_generic_driver_added),
	DEVMETHOD(bus_print_child,	smbus_print_child),
	DEVMETHOD(bus_read_ivar,	smbus_read_ivar),

	DEVMETHOD_END
};

driver_t smbus_driver = {
        "smbus",
        smbus_methods,
        sizeof(struct smbus_softc),
};

devclass_t smbus_devclass;

/*
 * At 'probe' time, we add all the devices which we know about to the
 * bus.  The generic attach routine will probe and attach them if they
 * are alive.
 */
static int
smbus_probe(device_t dev)
{

	device_set_desc(dev, "System Management Bus");

	return (0);
}

static int
smbus_attach(device_t dev)
{
	struct smbus_softc *sc = device_get_softc(dev);
	unsigned char addr;

	mtx_init(&sc->lock, device_get_nameunit(dev), "smbus", MTX_DEF);
	bus_generic_probe(dev);
	for (addr = SMBUS_ADDR_MIN; addr < SMBUS_ADDR_MAX; ++addr) {
		sc->addrs[addr] = addr;
		smbus_probe_device(dev, &sc->addrs[addr]);
	}
	bus_generic_attach(dev);

	return (0);
}

static int
smbus_detach(device_t dev)
{
	struct smbus_softc *sc = device_get_softc(dev);
	int error;

	error = bus_generic_detach(dev);
	if (error)
		return (error);
	mtx_destroy(&sc->lock);

	return (0);
}

void
smbus_generic_intr(device_t dev, u_char devaddr, char low, char high, int err)
{
}

static void
smbus_probe_device(device_t dev, u_char* addr)
{
	device_t child;
	int error;
	u_char cmd;
	u_char buf[2];

	cmd = 0x01;
	error = smbus_trans(dev, *addr, cmd,
			    SMB_TRANS_NOCNT | SMB_TRANS_NOREPORT,
			    NULL, 0, buf, 1, NULL);
	if (error == 0) {
		if (bootverbose)
			device_printf(dev, "Probed address 0x%02x\n", *addr);
		child = device_add_child(dev, NULL, -1);
		device_set_ivars(child, addr);
	}
}

static int
smbus_child_location_str(device_t parent, device_t child, char *buf,
    size_t buflen)
{
	unsigned char *addr;

	addr = device_get_ivars(child);
	if (addr)
		snprintf(buf, buflen, "addr=0x%x", *addr);
	else if (buflen)
		buf[0] = 0;
	return (0);
}

static int
smbus_print_child(device_t parent, device_t child)
{
	unsigned char *addr;
	int retval;

	addr = device_get_ivars(child);
	retval = bus_print_child_header(parent, child);
	if (addr)
		retval += printf(" at addr 0x%x", *addr);
	retval += bus_print_child_footer(parent, child);

	return (retval);
}

static int
smbus_read_ivar(device_t parent, device_t child, int which,
    uintptr_t *result)
{
	unsigned char *addr;

	addr = device_get_ivars(child);
	switch (which) {
	case SMBUS_IVAR_ADDR:
		*result = (addr == NULL) ? -1 : *addr;
		break;
	default:
		return (ENOENT);
	}
	return (0);
}

MODULE_VERSION(smbus, SMBUS_MODVER);