232 lines
5.2 KiB
C
232 lines
5.2 KiB
C
/*-
|
|
* Copyright (c) 1998, 2001 Nicolas Souchu, Marc Bouget
|
|
* 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.
|
|
*
|
|
*
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
/*
|
|
* I2C Bit-Banging over parallel port
|
|
*
|
|
* See the Official Philips interface description in lpbb(4)
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/module.h>
|
|
#include <sys/bus.h>
|
|
#include <sys/uio.h>
|
|
|
|
|
|
#include <dev/ppbus/ppbconf.h>
|
|
#include "ppbus_if.h"
|
|
#include <dev/ppbus/ppbio.h>
|
|
|
|
#include <dev/iicbus/iiconf.h>
|
|
#include <dev/iicbus/iicbus.h>
|
|
|
|
#include "iicbb_if.h"
|
|
|
|
static int lpbb_detect(device_t dev);
|
|
|
|
static void
|
|
lpbb_identify(driver_t *driver, device_t parent)
|
|
{
|
|
|
|
device_t dev;
|
|
|
|
dev = device_find_child(parent, "lpbb", 0);
|
|
if (!dev)
|
|
BUS_ADD_CHILD(parent, 0, "lpbb", -1);
|
|
}
|
|
|
|
static int
|
|
lpbb_probe(device_t dev)
|
|
{
|
|
|
|
/* Perhaps call this during identify instead? */
|
|
if (!lpbb_detect(dev))
|
|
return (ENXIO);
|
|
|
|
device_set_desc(dev, "Parallel I2C bit-banging interface");
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
lpbb_attach(device_t dev)
|
|
{
|
|
device_t bitbang;
|
|
|
|
/* add generic bit-banging code */
|
|
bitbang = device_add_child(dev, "iicbb", -1);
|
|
device_probe_and_attach(bitbang);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
lpbb_callback(device_t dev, int index, caddr_t *data)
|
|
{
|
|
device_t ppbus = device_get_parent(dev);
|
|
int error = 0;
|
|
int how;
|
|
|
|
switch (index) {
|
|
case IIC_REQUEST_BUS:
|
|
/* request the ppbus */
|
|
how = *(int *)data;
|
|
error = ppb_request_bus(ppbus, dev, how);
|
|
break;
|
|
|
|
case IIC_RELEASE_BUS:
|
|
/* release the ppbus */
|
|
error = ppb_release_bus(ppbus, dev);
|
|
break;
|
|
|
|
default:
|
|
error = EINVAL;
|
|
}
|
|
|
|
return (error);
|
|
}
|
|
|
|
#define SDA_out 0x80
|
|
#define SCL_out 0x08
|
|
#define SDA_in 0x80
|
|
#define SCL_in 0x08
|
|
#define ALIM 0x20
|
|
#define I2CKEY 0x50
|
|
|
|
static int lpbb_getscl(device_t dev)
|
|
{
|
|
return ((ppb_rstr(device_get_parent(dev)) & SCL_in) == SCL_in);
|
|
}
|
|
|
|
static int lpbb_getsda(device_t dev)
|
|
{
|
|
return ((ppb_rstr(device_get_parent(dev)) & SDA_in) == SDA_in);
|
|
}
|
|
|
|
static void lpbb_setsda(device_t dev, char val)
|
|
{
|
|
device_t ppbus = device_get_parent(dev);
|
|
|
|
if(val==0)
|
|
ppb_wdtr(ppbus, (u_char)SDA_out);
|
|
else
|
|
ppb_wdtr(ppbus, (u_char)~SDA_out);
|
|
}
|
|
|
|
static void lpbb_setscl(device_t dev, unsigned char val)
|
|
{
|
|
device_t ppbus = device_get_parent(dev);
|
|
|
|
if(val==0)
|
|
ppb_wctr(ppbus, (u_char)(ppb_rctr(ppbus)&~SCL_out));
|
|
else
|
|
ppb_wctr(ppbus, (u_char)(ppb_rctr(ppbus)|SCL_out));
|
|
}
|
|
|
|
static int lpbb_detect(device_t dev)
|
|
{
|
|
device_t ppbus = device_get_parent(dev);
|
|
|
|
if (ppb_request_bus(ppbus, dev, PPB_DONTWAIT)) {
|
|
device_printf(dev, "can't allocate ppbus\n");
|
|
return (0);
|
|
}
|
|
|
|
/* reset bus */
|
|
lpbb_setsda(dev, 1);
|
|
lpbb_setscl(dev, 1);
|
|
|
|
if ((ppb_rstr(ppbus) & I2CKEY) ||
|
|
((ppb_rstr(ppbus) & ALIM) != ALIM)) {
|
|
|
|
ppb_release_bus(ppbus, dev);
|
|
return (0);
|
|
}
|
|
|
|
ppb_release_bus(ppbus, dev);
|
|
|
|
return (1);
|
|
}
|
|
|
|
static int
|
|
lpbb_reset(device_t dev, u_char speed, u_char addr, u_char * oldaddr)
|
|
{
|
|
device_t ppbus = device_get_parent(dev);
|
|
|
|
if (ppb_request_bus(ppbus, dev, PPB_DONTWAIT)) {
|
|
device_printf(dev, "can't allocate ppbus\n");
|
|
return (0);
|
|
}
|
|
|
|
/* reset bus */
|
|
lpbb_setsda(dev, 1);
|
|
lpbb_setscl(dev, 1);
|
|
|
|
ppb_release_bus(ppbus, dev);
|
|
|
|
return (IIC_ENOADDR);
|
|
}
|
|
|
|
static devclass_t lpbb_devclass;
|
|
|
|
static device_method_t lpbb_methods[] = {
|
|
/* device interface */
|
|
DEVMETHOD(device_identify, lpbb_identify),
|
|
DEVMETHOD(device_probe, lpbb_probe),
|
|
DEVMETHOD(device_attach, lpbb_attach),
|
|
|
|
/* bus interface */
|
|
DEVMETHOD(bus_print_child, bus_generic_print_child),
|
|
|
|
/* iicbb interface */
|
|
DEVMETHOD(iicbb_callback, lpbb_callback),
|
|
DEVMETHOD(iicbb_setsda, lpbb_setsda),
|
|
DEVMETHOD(iicbb_setscl, lpbb_setscl),
|
|
DEVMETHOD(iicbb_getsda, lpbb_getsda),
|
|
DEVMETHOD(iicbb_getscl, lpbb_getscl),
|
|
DEVMETHOD(iicbb_reset, lpbb_reset),
|
|
|
|
{ 0, 0 }
|
|
};
|
|
|
|
static driver_t lpbb_driver = {
|
|
"lpbb",
|
|
lpbb_methods,
|
|
1,
|
|
};
|
|
|
|
DRIVER_MODULE(lpbb, ppbus, lpbb_driver, lpbb_devclass, 0, 0);
|
|
MODULE_DEPEND(lpbb, ppbus, 1, 1, 1);
|
|
MODULE_DEPEND(lpbb, iicbb, IICBB_MINVER, IICBB_PREFVER, IICBB_MAXVER);
|
|
MODULE_VERSION(lpbb, 1);
|