/*-
 * 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.
 *
 * $FreeBSD: src/sys/dev/smbus/smb.c,v 1.34.8.2 2006/09/22 19:19:16 jhb Exp $
 *
 */

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/uio.h>
#include <sys/fcntl.h>

#include "smbconf.h"
#include "smbus.h"
#include "smb.h"

#include "smbus_if.h"

#define BUFSIZE 1024

struct smb_softc {

	int sc_count;			/* >0 if device opened */
	cdev_t sc_devnode;
};

#define IIC_SOFTC(unit) \
	((struct smb_softc *)devclass_get_softc(smb_devclass, (unit)))

#define IIC_DEVICE(unit) \
	(devclass_get_device(smb_devclass, (unit)))

static void smb_identify(driver_t *driver, device_t parent);
static int smb_probe(device_t);
static int smb_attach(device_t);
static int smb_detach(device_t);

static devclass_t smb_devclass;

static device_method_t smb_methods[] = {
	/* device interface */
	DEVMETHOD(device_identify,	smb_identify),
	DEVMETHOD(device_probe,		smb_probe),
	DEVMETHOD(device_attach,	smb_attach),
	DEVMETHOD(device_detach,	smb_detach),

	/* smbus interface */
	DEVMETHOD(smbus_intr,		smbus_generic_intr),

	{ 0, 0 }
};

static driver_t smb_driver = {
	"smb",
	smb_methods,
	sizeof(struct smb_softc),
};

static	d_open_t	smbopen;
static	d_close_t	smbclose;
static	d_ioctl_t	smbioctl;

static struct dev_ops smb_ops = {
	{ "smb", 0, 0 },
	.d_open =	smbopen,
	.d_close =	smbclose,
	.d_ioctl =	smbioctl,
};

static void
smb_identify(driver_t *driver, device_t parent)
{
	if (device_find_child(parent, "smb", -1) == NULL)
		BUS_ADD_CHILD(parent, parent, 0, "smb", -1);
}

static int
smb_probe(device_t dev)
{
	device_set_desc(dev, "SMBus generic I/O");

	return (0);
}

static int
smb_attach(device_t dev)
{
	struct smb_softc *sc = (struct smb_softc *)device_get_softc(dev);

	if (!sc)
		return (ENOMEM);

	bzero(sc, sizeof(struct smb_softc *));

	sc->sc_devnode = make_dev(&smb_ops, device_get_unit(dev),
			UID_ROOT, GID_WHEEL,
			0600, "smb%d", device_get_unit(dev));

	return (0);
}

static int
smb_detach(device_t dev)
{
	struct smb_softc *sc = (struct smb_softc *)device_get_softc(dev);

	if (sc->sc_devnode)
		dev_ops_remove_minor(&smb_ops, device_get_unit(dev));

	return (0);
}

static int
smbopen (struct dev_open_args *ap)
{
	cdev_t dev = ap->a_head.a_dev;
	struct smb_softc *sc = IIC_SOFTC(minor(dev));

	if (sc == NULL)
		return (ENXIO);

	if (sc->sc_count != 0)
		return (EBUSY);

	sc->sc_count++;

	return (0);
}

static int
smbclose(struct dev_close_args *ap)
{
	cdev_t dev = ap->a_head.a_dev;
	struct smb_softc *sc = IIC_SOFTC(minor(dev));

	if (sc == NULL)
		return (ENXIO);

	if (sc->sc_count == 0)
		/* This is not supposed to happen. */
		return (0);

	sc->sc_count--;

	return (0);
}

#if 0
static int
smbwrite(struct dev_write_args *ap)
{
	return (EINVAL);
}

static int
smbread(struct dev_read_args *ap)
{
	return (EINVAL);
}
#endif

static int
smbioctl(struct dev_ioctl_args *ap)
{
	cdev_t dev = ap->a_head.a_dev;
	char buf[SMB_MAXBLOCKSIZE];
	device_t parent;
	struct smbcmd *s = (struct smbcmd *)ap->a_data;
	struct smb_softc *sc = IIC_SOFTC(minor(dev));
	device_t smbdev = IIC_DEVICE(minor(dev));
	int error;
	short w;
	u_char count;
	char c;

	if (sc == NULL)
		return (ENXIO);
	if (s == NULL)
		return (EINVAL);

	parent = device_get_parent(smbdev);

	/* Allocate the bus. */
	if ((error = smbus_request_bus(parent, smbdev,
			(ap->a_fflag & O_NONBLOCK) ? SMB_DONTWAIT : (SMB_WAIT | SMB_INTR))))
		return (error);

	switch (ap->a_cmd) {
	case SMB_QUICK_WRITE:
		error = smbus_error(smbus_quick(parent, s->slave, SMB_QWRITE));
		break;

	case SMB_QUICK_READ:
		error = smbus_error(smbus_quick(parent, s->slave, SMB_QREAD));
		break;

	case SMB_SENDB:
		error = smbus_error(smbus_sendb(parent, s->slave, s->cmd));
		break;

	case SMB_RECVB:
		error = smbus_error(smbus_recvb(parent, s->slave, &s->cmd));
		break;

	case SMB_WRITEB:
		error = smbus_error(smbus_writeb(parent, s->slave, s->cmd,
						s->data.byte));
		break;

	case SMB_WRITEW:
		error = smbus_error(smbus_writew(parent, s->slave,
						s->cmd, s->data.word));
		break;

	case SMB_READB:
		if (s->data.byte_ptr) {
			error = smbus_error(smbus_readb(parent, s->slave,
						s->cmd, &c));
			if (error)
				break;
			error = copyout(&c, s->data.byte_ptr,
					sizeof(*(s->data.byte_ptr)));
		}
		break;

	case SMB_READW:
		if (s->data.word_ptr) {
			error = smbus_error(smbus_readw(parent, s->slave,
						s->cmd, &w));
			if (error == 0) {
				error = copyout(&w, s->data.word_ptr,
						sizeof(*(s->data.word_ptr)));
			}
		}
		break;

	case SMB_PCALL:
		if (s->data.process.rdata) {
			error = smbus_error(smbus_pcall(parent, s->slave, s->cmd,
				s->data.process.sdata, &w));
			if (error)
				break;
			error = copyout(&w, s->data.process.rdata,
					sizeof(*(s->data.process.rdata)));
		}

		break;

	case SMB_BWRITE:
		if (s->count && s->data.byte_ptr) {
			if (s->count > SMB_MAXBLOCKSIZE)
				s->count = SMB_MAXBLOCKSIZE;
			error = copyin(s->data.byte_ptr, buf, s->count);
			if (error)
				break;
			error = smbus_error(smbus_bwrite(parent, s->slave,
						s->cmd, s->count, buf));
		}
		break;

	case SMB_OLD_BREAD:
	case SMB_BREAD:
		if (s->count && s->data.byte_ptr) {
			count = min(s->count, SMB_MAXBLOCKSIZE);
			error = smbus_error(smbus_bread(parent, s->slave,
						s->cmd, &count, buf));
			if (error)
				break;
			error = copyout(buf, s->data.byte_ptr,
			    min(count, s->count));
			s->count = count;
		}
		break;

	default:
		error = ENOTTY;
	}

	smbus_release_bus(parent, smbdev);

	return (error);
}

DRIVER_MODULE(smb, smbus, smb_driver, smb_devclass, NULL, NULL);
MODULE_DEPEND(smb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
MODULE_VERSION(smb, 1);