freebsd-dev/sys/dev/bktr/bktr_i2c.c
Nicolas Souchu dec0ec9e81 Return to previous check_for_i2c_devices() behaviour.
Cast the cmd parameter to unsigned char in every smbus call.

Submitted by: Roger Hardiman <roger@cs.strath.ac.uk>
1998-11-07 14:30:48 +00:00

413 lines
9.9 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: bt848_i2c.c,v 1.1 1998/10/31 11:26:38 nsouch Exp $
*
*/
/*
* I2C support for the bti2c chipset.
*
* From brooktree848.c <fsmp@freefall.org>
*/
#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 <pci/pcivar.h>
#include <pci/pcireg.h>
#include <machine/ioctl_meteor.h>
#include <machine/ioctl_bt848.h> /* extensions to ioctl_meteor.h */
#include <pci/brktree_reg.h>
#include <pci/bt848_i2c.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include <dev/smbus/smbconf.h>
#include "iicbb_if.h"
#include "smbus_if.h"
#include "pci.h"
#include "bktr.h"
#if (NBKTR > 0 && NPCI > 0)
#define I2C_DELAY 40
#define BTI2C_DEBUG(x) if (bti2c_debug) (x)
static int bti2c_debug = 0;
struct bti2c_softc {
bt848_ptr_t base;
int iic_owned; /* 1 if we own the iicbus */
int smb_owned; /* 1 if we own the smbbus */
device_t smbus;
device_t iicbus;
};
struct bt_data {
bt848_ptr_t base;
};
struct bt_data btdata[NBKTR];
static int bti2c_probe(device_t);
static int bti2c_attach(device_t);
static void bti2c_print_child(device_t, device_t);
static int bti2c_iic_callback(device_t, int, caddr_t *);
static void bti2c_iic_setlines(device_t, int, int);
static int bti2c_iic_getdataline(device_t);
static int bti2c_iic_reset(device_t, u_char, u_char, u_char *);
static int bti2c_smb_callback(device_t, int, caddr_t *);
static int bti2c_smb_writeb(device_t dev, u_char slave, char cmd, char byte);
static int bti2c_smb_writew(device_t dev, u_char slave, char cmd, short word);
static int bti2c_smb_readb(device_t dev, u_char slave, char cmd, char *byte);
static devclass_t bti2c_devclass;
static device_method_t bti2c_methods[] = {
/* device interface */
DEVMETHOD(device_probe, bti2c_probe),
DEVMETHOD(device_attach, bti2c_attach),
/* bus interface */
DEVMETHOD(bus_print_child, bti2c_print_child),
/* iicbb interface */
DEVMETHOD(iicbb_callback, bti2c_iic_callback),
DEVMETHOD(iicbb_setlines, bti2c_iic_setlines),
DEVMETHOD(iicbb_getdataline, bti2c_iic_getdataline),
DEVMETHOD(iicbb_reset, bti2c_iic_reset),
/* smbus interface */
DEVMETHOD(smbus_callback, bti2c_smb_callback),
DEVMETHOD(smbus_writeb, bti2c_smb_writeb),
DEVMETHOD(smbus_writew, bti2c_smb_writew),
DEVMETHOD(smbus_readb, bti2c_smb_readb),
{ 0, 0 }
};
static driver_t bti2c_driver = {
"bti2c",
bti2c_methods,
DRIVER_TYPE_MISC,
sizeof(struct bti2c_softc),
};
/*
* Call this to pass the base address of the bktr device to the
* bti2c_i2c layer and initialize all the I2C bus architecture
*/
int
bt848_i2c_attach(int unit, bt848_ptr_t base, struct bktr_i2c_softc *i2c_sc)
{
device_t interface;
device_t bitbang;
btdata[unit].base = base;
/* XXX add the I2C interface to the root_bus until pcibus is ready */
interface = device_add_child(root_bus, "bti2c", unit, NULL);
/* add bit-banging generic code onto bti2c interface */
bitbang = device_add_child(interface, "iicbb", -1, NULL);
/* probe and attach the interface, we need it NOW
* bit-banging code is also probed and attached */
device_probe_and_attach(interface);
device_probe_and_attach(bitbang);
/* smb and i2c interfaces are available for the bt848 chip
* connect bit-banging generic code to an iicbus */
if ((i2c_sc->iicbus = iicbus_alloc_bus(bitbang)))
device_probe_and_attach(i2c_sc->iicbus);
/* hardware i2c is actually smb over the bti2c interface */
if ((i2c_sc->smbus = smbus_alloc_bus(interface)))
device_probe_and_attach(i2c_sc->smbus);
return (0);
};
/*
* Not a real probe, we know the device exists since the device has
* been added after the successfull pci probe.
*/
static int
bti2c_probe(device_t dev)
{
device_set_desc(dev, "bt848 Hard/Soft I2C controller");
return (0);
}
static int
bti2c_attach(device_t dev)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
/* XXX should use ivars with pcibus or pcibus methods to access
* onboard memory */
sc->base = btdata[device_get_unit(dev)].base;
return (0);
}
static void
bti2c_print_child(device_t bus, device_t dev)
{
printf(" on %s%d", device_get_name(bus), device_get_unit(bus));
return;
}
static int
bti2c_smb_callback(device_t dev, int index, caddr_t *data)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
int error = 0;
int how;
/* test each time if we already have/haven't the iicbus
* to avoid deadlocks
*/
switch (index) {
case SMB_REQUEST_BUS:
if (!sc->iic_owned) {
/* request the iicbus */
how = *(int *)data;
error = iicbus_request_bus(sc->iicbus, dev, how);
if (!error)
sc->iic_owned = 1;
}
break;
case SMB_RELEASE_BUS:
if (sc->iic_owned) {
/* release the iicbus */
error = iicbus_release_bus(sc->iicbus, dev);
if (!error)
sc->iic_owned = 0;
}
break;
default:
error = EINVAL;
}
return (error);
}
static int
bti2c_iic_callback(device_t dev, int index, caddr_t *data)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
int error = 0;
int how;
/* test each time if we already have/haven't the smbus
* to avoid deadlocks
*/
switch (index) {
case IIC_REQUEST_BUS:
if (!sc->smb_owned) {
/* request the smbus */
how = *(int *)data;
error = smbus_request_bus(sc->smbus, dev, how);
if (!error)
sc->smb_owned = 1;
}
break;
case IIC_RELEASE_BUS:
if (sc->smb_owned) {
/* release the smbus */
error = smbus_release_bus(sc->smbus, dev);
if (!error)
sc->smb_owned = 0;
}
break;
default:
error = EINVAL;
}
return (error);
}
static int
bti2c_iic_reset(device_t dev, u_char speed, u_char addr, u_char * oldaddr)
{
if (oldaddr)
*oldaddr = 0; /* XXX */
return (IIC_ENOADDR);
}
static void
bti2c_iic_setlines(device_t dev, int ctrl, int data)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
bt848_ptr_t bti2c;
bti2c = sc->base;
bti2c->i2c_data_ctl = (ctrl << 1) | data;
DELAY(I2C_DELAY);
return;
}
static int
bti2c_iic_getdataline(device_t dev)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
bt848_ptr_t bti2c;
bti2c = sc->base;
return (bti2c->i2c_data_ctl & 0x1);
}
static int
bti2c_write(bt848_ptr_t bti2c, u_long data)
{
u_long x;
/* clear status bits */
bti2c->int_stat = (BT848_INT_RACK | BT848_INT_I2CDONE);
BTI2C_DEBUG(printf("w%lx", data));
/* write the address and data */
bti2c->i2c_data_ctl = data;
/* wait for completion */
for ( x = 0x7fffffff; x; --x ) { /* safety valve */
if ( bti2c->int_stat & BT848_INT_I2CDONE )
break;
}
/* check for ACK */
if ( !x || !(bti2c->int_stat & BT848_INT_RACK) ) {
BTI2C_DEBUG(printf("%c%c", (!x)?'+':'-',
(!(bti2c->int_stat & BT848_INT_RACK))?'+':'-'));
return (SMB_ENOACK);
}
BTI2C_DEBUG(printf("+"));
/* return OK */
return( 0 );
}
static int
bti2c_smb_writeb(device_t dev, u_char slave, char cmd, char byte)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
u_long data;
data = ((slave & 0xff) << 24) | ((byte & 0xff) << 16) | (u_char)cmd;
return (bti2c_write(sc->base, data));
}
/*
* byte1 becomes low byte of word
* byte2 becomes high byte of word
*/
static int
bti2c_smb_writew(device_t dev, u_char slave, char cmd, short word)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
u_long data;
char low, high;
low = (char)(word & 0xff);
high = (char)((word & 0xff00) >> 8);
data = ((slave & 0xff) << 24) | ((low & 0xff) << 16) |
((high & 0xff) << 8) | BT848_DATA_CTL_I2CW3B | (u_char)cmd;
return (bti2c_write(sc->base, data));
}
/*
* The Bt878 and Bt879 differed on the treatment of i2c commands
*/
static int
bti2c_smb_readb(device_t dev, u_char slave, char cmd, char *byte)
{
struct bti2c_softc *sc = (struct bti2c_softc *)device_get_softc(dev);
bt848_ptr_t bti2c;
u_long x;
bti2c = sc->base;
/* clear status bits */
bti2c->int_stat = (BT848_INT_RACK | BT848_INT_I2CDONE);
bti2c->i2c_data_ctl = ((slave & 0xff) << 24) | (u_char)cmd;
BTI2C_DEBUG(printf("r%lx/", (u_long)(((slave & 0xff) << 24) | (u_char)cmd)));
/* wait for completion */
for ( x = 0x7fffffff; x; --x ) { /* safety valve */
if ( bti2c->int_stat & BT848_INT_I2CDONE )
break;
}
/* check for ACK */
if ( !x || !(bti2c->int_stat & BT848_INT_RACK) ) {
BTI2C_DEBUG(printf("r%c%c", (!x)?'+':'-',
(!(bti2c->int_stat & BT848_INT_RACK))?'+':'-'));
return (SMB_ENOACK);
}
*byte = (char)((bti2c->i2c_data_ctl >> 8) & 0xff);
BTI2C_DEBUG(printf("r%x+", *byte));
return (0);
}
DRIVER_MODULE(bti2c, root, bti2c_driver, bti2c_devclass, 0, 0);
#endif