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/*-
* Copyright (c) 1998 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.
*
* $FreeBSD$
*
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <dev/smbus/smbconf.h>
#include <dev/smbus/smbus.h>
#include "smbus_if.h"
/*
* smbus_intr()
*/
void
smbus_intr(device_t bus, u_char devaddr, char low, char high, int error)
{
struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
/* call owner's intr routine */
if (sc->owner)
SMBUS_INTR(sc->owner, devaddr, low, high, error);
return;
}
/*
* smbus_error()
*
* Converts an smbus error to a unix error.
*/
int
smbus_error(int smb_error)
{
int error = 0;
if (smb_error == SMB_ENOERR)
return (0);
if (smb_error & (SMB_ENOTSUPP)) {
error = ENODEV;
} else if (smb_error & (SMB_ENOACK)) {
error = ENXIO;
} else if (smb_error & (SMB_ETIMEOUT)) {
error = EWOULDBLOCK;
} else if (smb_error & (SMB_EBUSY)) {
error = EBUSY;
} else {
error = EINVAL;
}
return (error);
}
/*
* smbus_alloc_bus()
*
* Allocate a new bus connected to the given parent device
*/
device_t
smbus_alloc_bus(device_t parent)
{
device_t child;
/* add the bus to the parent */
child = device_add_child(parent, "smbus", -1);
return (child);
}
static int
smbus_poll(struct smbus_softc *sc, int how)
{
int error;
switch (how) {
case (SMB_WAIT | SMB_INTR):
error = tsleep(sc, SMBPRI|PCATCH, "smbreq", 0);
break;
case (SMB_WAIT | SMB_NOINTR):
error = tsleep(sc, SMBPRI, "smbreq", 0);
break;
default:
return (EWOULDBLOCK);
break;
}
return (error);
}
/*
* smbus_request_bus()
*
* Allocate the device to perform transfers.
*
* how : SMB_WAIT or SMB_DONTWAIT
*/
int
smbus_request_bus(device_t bus, device_t dev, int how)
{
struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
int s, error = 0;
/* first, ask the underlying layers if the request is ok */
do {
error = SMBUS_CALLBACK(device_get_parent(bus),
SMB_REQUEST_BUS, (caddr_t)&how);
if (error)
error = smbus_poll(sc, how);
} while (error == EWOULDBLOCK);
while (!error) {
s = splhigh();
if (sc->owner && sc->owner != dev) {
splx(s);
error = smbus_poll(sc, how);
} else {
sc->owner = dev;
splx(s);
return (0);
}
/* free any allocated resource */
if (error)
SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS,
(caddr_t)&how);
}
return (error);
}
/*
* smbus_release_bus()
*
* Release the device allocated with smbus_request_dev()
*/
int
smbus_release_bus(device_t bus, device_t dev)
{
struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
int s, error;
/* first, ask the underlying layers if the release is ok */
error = SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS, NULL);
if (error)
return (error);
s = splhigh();
if (sc->owner != dev) {
splx(s);
return (EACCES);
}
sc->owner = 0;
splx(s);
/* wakeup waiting processes */
wakeup(sc);
return (0);
}
/*
* smbus_get_addr()
*
* Get the I2C 7 bits address of the device
*/
u_char
smbus_get_addr(device_t dev)
{
uintptr_t addr;
device_t parent = device_get_parent(dev);
BUS_READ_IVAR(parent, dev, SMBUS_IVAR_ADDR, &addr);
return ((u_char)addr);
}
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