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/* ------------------------------------------------------------------------- */
/* i2c-velleman.c i2c-hw access for Velleman K9000 adapters */
/* ------------------------------------------------------------------------- */
/* Copyright (C) 1995-96, 2000 Simon G. Vogl
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* ------------------------------------------------------------------------- */
/* $Id: i2c-velleman.c,v 1.19 2000/01/24 02:06:33 mds Exp $ */
#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h> /* for 2.0 kernels to get NULL */
#include <asm/errno.h> /* for 2.0 kernels to get ENODEV */
#include <asm/io.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
/* ----- global defines ----------------------------------------------- */
#define DEB(x) /* should be reasonable open, close &c. */
#define DEB2(x) /* low level debugging - very slow */
#define DEBE(x) x /* error messages */
/* Pin Port Inverted name */
#define I2C_SDA 0x02 /* ctrl bit 1 (inv) */
#define I2C_SCL 0x08 /* ctrl bit 3 (inv) */
#define I2C_SDAIN 0x10 /* stat bit 4 */
#define I2C_SCLIN 0x08 /* ctrl bit 3 (inv)(reads own output)*/
#define I2C_DMASK 0xfd
#define I2C_CMASK 0xf7
/* --- Convenience defines for the parallel port: */
#define BASE (unsigned int)(data)
#define DATA BASE /* Centronics data port */
#define STAT (BASE+1) /* Centronics status port */
#define CTRL (BASE+2) /* Centronics control port */
#define DEFAULT_BASE 0x378
static int base=0;
/* ----- local functions --------------------------------------------------- */
static void bit_velle_setscl(void *data, int state)
{
if (state) {
outb(inb(CTRL) & I2C_CMASK, CTRL);
} else {
outb(inb(CTRL) | I2C_SCL, CTRL);
}
}
static void bit_velle_setsda(void *data, int state)
{
if (state) {
outb(inb(CTRL) & I2C_DMASK , CTRL);
} else {
outb(inb(CTRL) | I2C_SDA, CTRL);
}
}
static int bit_velle_getscl(void *data)
{
return ( 0 == ( (inb(CTRL)) & I2C_SCLIN ) );
}
static int bit_velle_getsda(void *data)
{
return ( 0 != ( (inb(STAT)) & I2C_SDAIN ) );
}
static int bit_velle_init(void)
{
if (check_region(base,(base == 0x3bc)? 3 : 8) < 0 ) {
DEBE(printk("i2c-velleman.o: Port %#x already in use.\n",
base));
return -ENODEV;
} else {
request_region(base, (base == 0x3bc)? 3 : 8,
"i2c (Vellemann adapter)");
bit_velle_setsda((void*)base,1);
bit_velle_setscl((void*)base,1);
}
return 0;
}
static void __exit bit_velle_exit(void)
{
release_region( base , (base == 0x3bc)? 3 : 8 );
}
static int bit_velle_reg(struct i2c_client *client)
{
return 0;
}
static int bit_velle_unreg(struct i2c_client *client)
{
return 0;
}
static void bit_velle_inc_use(struct i2c_adapter *adap)
{
#ifdef MODULE
MOD_INC_USE_COUNT;
#endif
}
static void bit_velle_dec_use(struct i2c_adapter *adap)
{
#ifdef MODULE
MOD_DEC_USE_COUNT;
#endif
}
/* ------------------------------------------------------------------------
* Encapsulate the above functions in the correct operations structure.
* This is only done when more than one hardware adapter is supported.
*/
static struct i2c_algo_bit_data bit_velle_data = {
NULL,
bit_velle_setsda,
bit_velle_setscl,
bit_velle_getsda,
bit_velle_getscl,
10, 10, 100, /* waits, timeout */
};
static struct i2c_adapter bit_velle_ops = {
"Velleman K8000",
I2C_HW_B_VELLE,
NULL,
&bit_velle_data,
bit_velle_inc_use,
bit_velle_dec_use,
bit_velle_reg,
bit_velle_unreg,
};
int __init i2c_bitvelle_init(void)
{
printk("i2c-velleman.o: i2c Velleman K8000 adapter module\n");
if (base==0) {
/* probe some values */
base=DEFAULT_BASE;
bit_velle_data.data=(void*)DEFAULT_BASE;
if (bit_velle_init()==0) {
if(i2c_bit_add_bus(&bit_velle_ops) < 0)
return -ENODEV;
} else {
return -ENODEV;
}
} else {
bit_velle_data.data=(void*)base;
if (bit_velle_init()==0) {
if(i2c_bit_add_bus(&bit_velle_ops) < 0)
return -ENODEV;
} else {
return -ENODEV;
}
}
printk("i2c-velleman.o: found device at %#x.\n",base);
return 0;
}
EXPORT_NO_SYMBOLS;
#ifdef MODULE
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
MODULE_DESCRIPTION("I2C-Bus adapter routines for Velleman K8000 adapter");
MODULE_LICENSE("GPL");
MODULE_PARM(base, "i");
int init_module(void)
{
return i2c_bitvelle_init();
}
void cleanup_module(void)
{
i2c_bit_del_bus(&bit_velle_ops);
bit_velle_exit();
}
#endif
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