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freebsd/sys/dev/iicbus/iicsmb.c
Nicolas Souchu 04f89a63cb iicbb is generic support for I2C bit-banging.
Other files: timeout management added to the I2C framework.
1998-10-31 11:31:07 +00:00

501 lines
11 KiB
C

/*-
* 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.
*
* $Id: iicsmb.c,v 1.1.1.1 1998/09/03 20:51:50 nsouch Exp $
*
*/
/*
* I2C to SMB bridge
*
* Example:
*
* smb bttv
* \ /
* smbus
* / \
* iicsmb bti2c
* |
* iicbus
* / | \
* iicbb pcf ...
* |
* lpbb
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/buf.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <machine/clock.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include <dev/smbus/smbconf.h>
#include "iicbus_if.h"
#include "smbus_if.h"
struct iicsmb_softc {
#define SMB_WAITING_ADDR 0x0
#define SMB_WAITING_LOW 0x1
#define SMB_WAITING_HIGH 0x2
#define SMB_DONE 0x3
int state;
u_char devaddr; /* slave device address */
char low; /* low byte received first */
char high; /* high byte */
device_t smbus;
};
static int iicsmb_probe(device_t);
static int iicsmb_attach(device_t);
static void iicsmb_print_child(device_t, device_t);
static void iicsmb_intr(device_t dev, int event, char *buf);
static int iicsmb_callback(device_t dev, int index, caddr_t data);
static int iicsmb_quick(device_t dev, u_char slave, int how);
static int iicsmb_sendb(device_t dev, u_char slave, char byte);
static int iicsmb_recvb(device_t dev, u_char slave, char *byte);
static int iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte);
static int iicsmb_writew(device_t dev, u_char slave, char cmd, short word);
static int iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte);
static int iicsmb_readw(device_t dev, u_char slave, char cmd, short *word);
static int iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata);
static int iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf);
static int iicsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf);
static devclass_t iicsmb_devclass;
static device_method_t iicsmb_methods[] = {
/* device interface */
DEVMETHOD(device_probe, iicsmb_probe),
DEVMETHOD(device_attach, iicsmb_attach),
/* bus interface */
DEVMETHOD(bus_print_child, iicsmb_print_child),
/* iicbus interface */
DEVMETHOD(iicbus_intr, iicsmb_intr),
/* smbus interface */
DEVMETHOD(smbus_callback, iicsmb_callback),
DEVMETHOD(smbus_quick, iicsmb_quick),
DEVMETHOD(smbus_sendb, iicsmb_sendb),
DEVMETHOD(smbus_recvb, iicsmb_recvb),
DEVMETHOD(smbus_writeb, iicsmb_writeb),
DEVMETHOD(smbus_writew, iicsmb_writew),
DEVMETHOD(smbus_readb, iicsmb_readb),
DEVMETHOD(smbus_readw, iicsmb_readw),
DEVMETHOD(smbus_pcall, iicsmb_pcall),
DEVMETHOD(smbus_bwrite, iicsmb_bwrite),
DEVMETHOD(smbus_bread, iicsmb_bread),
{ 0, 0 }
};
static driver_t iicsmb_driver = {
"iicsmb",
iicsmb_methods,
DRIVER_TYPE_MISC,
sizeof(struct iicsmb_softc),
};
static int
iicsmb_probe(device_t dev)
{
struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev);
sc->smbus = smbus_alloc_bus(dev);
if (!sc->smbus)
return (EINVAL); /* XXX don't know what to return else */
return (0);
}
static int
iicsmb_attach(device_t dev)
{
struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev);
/* probe and attach the smbus */
device_probe_and_attach(sc->smbus);
return (0);
}
static void
iicsmb_print_child(device_t bus, device_t dev)
{
printf(" on %s%d", device_get_name(bus), device_get_unit(bus));
return;
}
/*
* iicsmb_intr()
*
* iicbus interrupt handler
*/
static void
iicsmb_intr(device_t dev, int event, char *buf)
{
struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev);
switch (event) {
case INTR_GENERAL:
case INTR_START:
sc->state = SMB_WAITING_ADDR;
break;
case INTR_STOP:
/* call smbus intr handler */
smbus_intr(sc->smbus, sc->devaddr,
sc->low, sc->high, SMB_ENOERR);
break;
case INTR_RECEIVE:
switch (sc->state) {
case SMB_DONE:
/* XXX too much data, discard */
printf("%s: too much data from 0x%x\n", __FUNCTION__,
sc->devaddr & 0xff);
goto end;
case SMB_WAITING_ADDR:
sc->devaddr = (u_char)*buf;
sc->state = SMB_WAITING_LOW;
break;
case SMB_WAITING_LOW:
sc->low = *buf;
sc->state = SMB_WAITING_HIGH;
break;
case SMB_WAITING_HIGH:
sc->high = *buf;
sc->state = SMB_DONE;
break;
}
end:
break;
case INTR_TRANSMIT:
case INTR_NOACK:
break;
case INTR_ERROR:
switch (*buf) {
case IIC_EBUSERR:
smbus_intr(sc->smbus, sc->devaddr, 0, 0, SMB_EBUSERR);
break;
default:
printf("%s unknown error 0x%x!\n", __FUNCTION__,
(int)*buf);
break;
}
break;
default:
panic("%s: unknown event (%d)!", __FUNCTION__, event);
}
return;
}
static int
iicsmb_callback(device_t dev, int index, caddr_t data)
{
device_t parent = device_get_parent(dev);
int error = 0;
int how;
switch (index) {
case SMB_REQUEST_BUS:
/* request underlying iicbus */
how = *(int *)data;
error = iicbus_request_bus(parent, dev, how);
break;
case SMB_RELEASE_BUS:
/* release underlying iicbus */
error = iicbus_release_bus(parent, dev);
break;
default:
error = EINVAL;
}
return (error);
}
static int
iicsmb_quick(device_t dev, u_char slave, int how)
{
device_t parent = device_get_parent(dev);
int error;
switch (how) {
case SMB_QWRITE:
error = iicbus_start(parent, slave & ~LSB, 0);
break;
case SMB_QREAD:
error = iicbus_start(parent, slave | LSB, 0);
break;
default:
error = EINVAL;
break;
}
if (!error)
error = iicbus_stop(parent);
return (error);
}
static int
iicsmb_sendb(device_t dev, u_char slave, char byte)
{
device_t parent = device_get_parent(dev);
int error, sent;
error = iicbus_start(parent, slave & ~LSB, 0);
if (!error) {
error = iicbus_write(parent, &byte, 1, &sent, 0);
iicbus_stop(parent);
}
return (error);
}
static int
iicsmb_recvb(device_t dev, u_char slave, char *byte)
{
device_t parent = device_get_parent(dev);
int error, read;
error = iicbus_start(parent, slave | LSB, 0);
if (!error) {
error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, 0);
iicbus_stop(parent);
}
return (error);
}
static int
iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte)
{
device_t parent = device_get_parent(dev);
int error, sent;
error = iicbus_start(parent, slave & ~LSB, 0);
if (!error) {
if (!(error = iicbus_write(parent, &cmd, 1, &sent, 0)))
error = iicbus_write(parent, &byte, 1, &sent, 0);
iicbus_stop(parent);
}
return (error);
}
static int
iicsmb_writew(device_t dev, u_char slave, char cmd, short word)
{
device_t parent = device_get_parent(dev);
int error, sent;
char low = (char)(word & 0xff);
char high = (char)((word & 0xff00) >> 8);
error = iicbus_start(parent, slave & ~LSB, 0);
if (!error) {
if (!(error = iicbus_write(parent, &cmd, 1, &sent, 0)))
if (!(error = iicbus_write(parent, &low, 1, &sent, 0)))
error = iicbus_write(parent, &high, 1, &sent, 0);
iicbus_stop(parent);
}
return (error);
}
static int
iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte)
{
device_t parent = device_get_parent(dev);
int error, sent, read;
if ((error = iicbus_start(parent, slave & ~LSB, 0)))
return (error);
if ((error = iicbus_write(parent, &cmd, 1, &sent, 0)))
goto error;
if ((error = iicbus_repeated_start(parent, slave | LSB, 0)))
goto error;
if ((error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, 0)))
goto error;
error:
iicbus_stop(parent);
return (error);
}
#define BUF2SHORT(low,high) \
((short)(((high) & 0xff) << 8) | (short)((low) & 0xff))
static int
iicsmb_readw(device_t dev, u_char slave, char cmd, short *word)
{
device_t parent = device_get_parent(dev);
int error, sent, read;
char buf[2];
if ((error = iicbus_start(parent, slave & ~LSB, 0)))
return (error);
if ((error = iicbus_write(parent, &cmd, 1, &sent, 0)))
goto error;
if ((error = iicbus_repeated_start(parent, slave | LSB, 0)))
goto error;
if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, 0)))
goto error;
/* first, receive low, then high byte */
*word = BUF2SHORT(buf[0], buf[1]);
error:
iicbus_stop(parent);
return (error);
}
static int
iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata)
{
device_t parent = device_get_parent(dev);
int error, sent, read;
char buf[2];
if ((error = iicbus_start(parent, slave & ~LSB, 0)))
return (error);
if ((error = iicbus_write(parent, &cmd, 1, &sent, 0)))
goto error;
/* first, send low, then high byte */
buf[0] = (char)(sdata & 0xff);
buf[1] = (char)((sdata & 0xff00) >> 8);
if ((error = iicbus_write(parent, buf, 2, &sent, 0)))
goto error;
if ((error = iicbus_repeated_start(parent, slave | LSB, 0)))
goto error;
if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, 0)))
goto error;
/* first, receive low, then high byte */
*rdata = BUF2SHORT(buf[0], buf[1]);
error:
iicbus_stop(parent);
return (error);
}
static int
iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
{
device_t parent = device_get_parent(dev);
int error, sent;
if ((error = iicbus_start(parent, slave & ~LSB, 0)))
goto error;
if ((error = iicbus_write(parent, &cmd, 1, &sent, 0)))
goto error;
if ((error = iicbus_write(parent, buf, (int)count, &sent, 0)))
goto error;
if ((error = iicbus_stop(parent)))
goto error;
error:
return (error);
}
static int
iicsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf)
{
device_t parent = device_get_parent(dev);
int error, sent, read;
if ((error = iicbus_start(parent, slave & ~LSB, 0)))
return (error);
if ((error = iicbus_write(parent, &cmd, 1, &sent, 0)))
goto error;
if ((error = iicbus_repeated_start(parent, slave | LSB, 0)))
goto error;
if ((error = iicbus_read(parent, buf, (int)count, &read,
IIC_LAST_READ, 0)))
goto error;
error:
iicbus_stop(parent);
return (error);
}
DRIVER_MODULE(iicsmb, iicbus, iicsmb_driver, iicsmb_devclass, 0, 0);