freebsd-skq/sys/arm/xscale/ixp425/ixp425_iic.c
Warner Losh a698b62cf5 trim trailing spaces that have accumulated over the years (these files
served as the basis for too many other platforms).
2012-06-13 04:38:09 +00:00

196 lines
5.0 KiB
C

/*
* Copyright (c) 2006 Kevin Lo. 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 WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/uio.h>
#include <arm/xscale/ixp425/ixp425reg.h>
#include <arm/xscale/ixp425/ixp425var.h>
#include <arm/xscale/ixp425/ixdp425reg.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include "iicbb_if.h"
#define I2C_DELAY 10
/* bit clr/set shorthands */
#define GPIO_CONF_CLR(sc, reg, mask) \
GPIO_CONF_WRITE_4(sc, reg, GPIO_CONF_READ_4(sc, reg) &~ (mask))
#define GPIO_CONF_SET(sc, reg, mask) \
GPIO_CONF_WRITE_4(sc, reg, GPIO_CONF_READ_4(sc, reg) | (mask))
struct ixpiic_softc {
device_t sc_dev;
bus_space_tag_t sc_iot;
bus_space_handle_t sc_gpio_ioh;
device_t iicbb;
};
static struct ixpiic_softc *ixpiic_sc = NULL;
static int
ixpiic_probe(device_t dev)
{
device_set_desc(dev, "IXP4XX GPIO-Based I2C Interface");
return (0);
}
static int
ixpiic_attach(device_t dev)
{
struct ixpiic_softc *sc = device_get_softc(dev);
struct ixp425_softc *sa = device_get_softc(device_get_parent(dev));
ixpiic_sc = sc;
sc->sc_dev = dev;
sc->sc_iot = sa->sc_iot;
sc->sc_gpio_ioh = sa->sc_gpio_ioh;
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER,
GPIO_I2C_SCL_BIT | GPIO_I2C_SDA_BIT);
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOUTR,
GPIO_I2C_SCL_BIT | GPIO_I2C_SDA_BIT);
/* add generic bit-banging code */
if ((sc->iicbb = device_add_child(dev, "iicbb", -1)) == NULL)
device_printf(dev, "could not add iicbb\n");
/* probe and attach the bit-banging code */
device_probe_and_attach(sc->iicbb);
return (0);
}
static int
ixpiic_callback(device_t dev, int index, caddr_t data)
{
return (0);
}
static int
ixpiic_getscl(device_t dev)
{
struct ixpiic_softc *sc = ixpiic_sc;
uint32_t reg;
IXP4XX_GPIO_LOCK();
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SCL_BIT);
reg = GPIO_CONF_READ_4(sc, IXP425_GPIO_GPINR);
IXP4XX_GPIO_UNLOCK();
return (reg & GPIO_I2C_SCL_BIT);
}
static int
ixpiic_getsda(device_t dev)
{
struct ixpiic_softc *sc = ixpiic_sc;
uint32_t reg;
IXP4XX_GPIO_LOCK();
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
reg = GPIO_CONF_READ_4(sc, IXP425_GPIO_GPINR);
IXP4XX_GPIO_UNLOCK();
return (reg & GPIO_I2C_SDA_BIT);
}
static void
ixpiic_setsda(device_t dev, int val)
{
struct ixpiic_softc *sc = ixpiic_sc;
IXP4XX_GPIO_LOCK();
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOUTR, GPIO_I2C_SDA_BIT);
if (val)
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
else
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOER, GPIO_I2C_SDA_BIT);
IXP4XX_GPIO_UNLOCK();
DELAY(I2C_DELAY);
}
static void
ixpiic_setscl(device_t dev, int val)
{
struct ixpiic_softc *sc = ixpiic_sc;
IXP4XX_GPIO_LOCK();
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOUTR, GPIO_I2C_SCL_BIT);
if (val)
GPIO_CONF_SET(sc, IXP425_GPIO_GPOER, GPIO_I2C_SCL_BIT);
else
GPIO_CONF_CLR(sc, IXP425_GPIO_GPOER, GPIO_I2C_SCL_BIT);
IXP4XX_GPIO_UNLOCK();
DELAY(I2C_DELAY);
}
static int
ixpiic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
{
/* reset bus */
ixpiic_setsda(dev, 1);
ixpiic_setscl(dev, 1);
return (IIC_ENOADDR);
}
static device_method_t ixpiic_methods[] = {
/* device interface */
DEVMETHOD(device_probe, ixpiic_probe),
DEVMETHOD(device_attach, ixpiic_attach),
/* iicbb interface */
DEVMETHOD(iicbb_callback, ixpiic_callback),
DEVMETHOD(iicbb_setsda, ixpiic_setsda),
DEVMETHOD(iicbb_setscl, ixpiic_setscl),
DEVMETHOD(iicbb_getsda, ixpiic_getsda),
DEVMETHOD(iicbb_getscl, ixpiic_getscl),
DEVMETHOD(iicbb_reset, ixpiic_reset),
{ 0, 0 }
};
static driver_t ixpiic_driver = {
"ixpiic",
ixpiic_methods,
sizeof(struct ixpiic_softc),
};
static devclass_t ixpiic_devclass;
DRIVER_MODULE(ixpiic, ixp, ixpiic_driver, ixpiic_devclass, 0, 0);
DRIVER_MODULE(iicbb, ixpiic, iicbb_driver, iicbb_devclass, 0, 0);