/*-
 * Copyright 2003 John-Mark Gurney
 * 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.
 *
 * $Id: zr_i2c.c,v 1.8 2003/04/30 16:22:47 jmg Exp $
 */

/*
 * Cribbed from lpbb, bktr_i2c and iicbb
 */
#include <sys/param.h>  /* defines used in kernel.h */
#include <sys/systm.h>  /* uprintf */
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/bus.h>  /* structs, prototypes for pci bus stuff */
#include <machine/bus_memio.h>
#include <machine/bus.h>

#include <dev/videocode/ioctl_video.h>

#include <dev/postoffice/postoffice.h>

#include <dev/zr/zr_reg.h>
#include <dev/zr/zr_os.h>

#include <dev/iicbus/iiconf.h>

int
zr_i2c_attach(device_t dev)
{
	struct zr_softc *zr = (struct zr_softc *)device_get_softc(dev);
	struct zr_i2c_softc *i2c = &zr->zr_i2c_sc;

	if (!mtx_initialized(&i2c->zi_bus_owned))
		mtx_init(&i2c->zi_bus_owned, device_get_nameunit(dev),
		    "zr_i2c", MTX_DEF);
	else
		printf("zi_bus_owned already initalized\n");

	/* add generic bit-banging code */
	i2c->zi_iicbb = device_add_child(dev, "iicbb", -1);
	if (i2c->zi_iicbb == NULL)
		return ENXIO;

	device_probe_and_attach(i2c->zi_iicbb);

	return (0);
}

int
zr_i2c_detach(device_t dev)
{
	struct zr_softc *zr = (struct zr_softc *)device_get_softc(dev);
	struct zr_i2c_softc *i2c = &zr->zr_i2c_sc;
	int error = 0;


	if ((error = device_detach(i2c->zi_iicbb)))
		goto error;
	if ((error = device_delete_child(dev, i2c->zi_iicbb)))
		goto error;
	i2c->zi_iicbb = NULL;

	mtx_destroy(&i2c->zi_bus_owned);

error:
	return error;
}

int
zr_i2c_callback(device_t dev, int index, caddr_t *data)
{
	struct zr_softc *zr = (struct zr_softc *)device_get_softc(dev);
	struct zr_i2c_softc *i2c = &zr->zr_i2c_sc;
	int error = 0;

	switch (index) {
	case IIC_REQUEST_BUS:
		if (mtx_trylock(&i2c->zi_bus_owned) == 0)
			error = EWOULDBLOCK;
		break;
	case IIC_RELEASE_BUS:
		if (mtx_owned(&i2c->zi_bus_owned) == 0)
			error = EINVAL;
		else
			mtx_unlock(&i2c->zi_bus_owned);
		break;
	}

	return error;
}

static void
zr_i2c_set(device_t dev, uint32_t pos, char val)
{
	struct zr_softc *zr = device_get_softc(dev);
	int res;

	res = zr_read_asrs(zr, ZR_I2C_REG);
	if (val == 0)
		zr_write_asrs(zr, ZR_I2C_REG, res&~pos);
	else
		zr_write_asrs(zr, ZR_I2C_REG, res|pos);
}

void
zr_i2c_setscl(device_t dev, char val)
{
	zr_i2c_set(dev, ZR_I2C_SCL, val);
}

void
zr_i2c_setsda(device_t dev, char val)
{
	zr_i2c_set(dev, ZR_I2C_SDA, val);
}

int
zr_i2c_getscl(device_t dev)
{
	ZR_SOFTC;

	return ZR_READ_ASR(zr, ZR_I2C_REG, i2c, SCL);
}

int
zr_i2c_getsda(device_t dev)
{
	ZR_SOFTC;

	return ZR_READ_ASR(zr, ZR_I2C_REG, i2c, SDA);
}

int
zr_i2c_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
{
	/* reset bus */
	zr_i2c_setsda(dev, 1);
	zr_i2c_setscl(dev, 1);

	return (IIC_ENOADDR);
}