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/*
comedi/drivers/pcmad.c
Hardware driver for Winsystems PCM-A/D12 and PCM-A/D16
COMEDI - Linux Control and Measurement Device Interface
Copyright (C) 2000,2001 David A. Schleef <ds@schleef.org>
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.
*/
/*
Driver: pcmad
Description: Winsystems PCM-A/D12, PCM-A/D16
Author: ds
Devices: [Winsystems] PCM-A/D12 (pcmad12), PCM-A/D16 (pcmad16)
Status: untested
This driver was written on a bet that I couldn't write a driver
in less than 2 hours. I won the bet, but never got paid. =(
Configuration options:
[0] - I/O port base
[1] - unused
[2] - Analog input reference
0 = single ended
1 = differential
[3] - Analog input encoding (must match jumpers)
0 = straight binary
1 = two's complement
*/
#include <linux/interrupt.h>
#include "../comedidev.h"
#include <linux/ioport.h>
#define PCMAD_SIZE 4
#define PCMAD_STATUS 0
#define PCMAD_LSB 1
#define PCMAD_MSB 2
#define PCMAD_CONVERT 1
struct pcmad_board_struct {
const char *name;
int n_ai_bits;
};
struct pcmad_priv_struct {
int differential;
int twos_comp;
};
#define devpriv ((struct pcmad_priv_struct *)dev->private)
#define TIMEOUT 100
static int pcmad_ai_insn_read(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data)
{
const struct pcmad_board_struct *board = comedi_board(dev);
int i;
int chan;
int n;
chan = CR_CHAN(insn->chanspec);
for (n = 0; n < insn->n; n++) {
outb(chan, dev->iobase + PCMAD_CONVERT);
for (i = 0; i < TIMEOUT; i++) {
if ((inb(dev->iobase + PCMAD_STATUS) & 0x3) == 0x3)
break;
}
data[n] = inb(dev->iobase + PCMAD_LSB);
data[n] |= (inb(dev->iobase + PCMAD_MSB) << 8);
if (devpriv->twos_comp)
data[n] ^= (1 << (board->n_ai_bits - 1));
}
return n;
}
/*
* options:
* 0 i/o base
* 1 unused
* 2 0=single ended 1=differential
* 3 0=straight binary 1=two's comp
*/
static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
const struct pcmad_board_struct *board = comedi_board(dev);
int ret;
struct comedi_subdevice *s;
unsigned long iobase;
iobase = it->options[0];
printk(KERN_INFO "comedi%d: pcmad: 0x%04lx ", dev->minor, iobase);
if (!request_region(iobase, PCMAD_SIZE, "pcmad")) {
printk(KERN_CONT "I/O port conflict\n");
return -EIO;
}
printk(KERN_CONT "\n");
dev->iobase = iobase;
ret = comedi_alloc_subdevices(dev, 1);
if (ret)
return ret;
ret = alloc_private(dev, sizeof(struct pcmad_priv_struct));
if (ret < 0)
return ret;
dev->board_name = board->name;
s = dev->subdevices + 0;
s->type = COMEDI_SUBD_AI;
s->subdev_flags = SDF_READABLE | AREF_GROUND;
s->n_chan = 16; /* XXX */
s->len_chanlist = 1;
s->insn_read = pcmad_ai_insn_read;
s->maxdata = (1 << board->n_ai_bits) - 1;
s->range_table = &range_unknown;
return 0;
}
static void pcmad_detach(struct comedi_device *dev)
{
if (dev->irq)
free_irq(dev->irq, dev);
if (dev->iobase)
release_region(dev->iobase, PCMAD_SIZE);
}
static const struct pcmad_board_struct pcmad_boards[] = {
{
.name = "pcmad12",
.n_ai_bits = 12,
}, {
.name = "pcmad16",
.n_ai_bits = 16,
},
};
static struct comedi_driver pcmad_driver = {
.driver_name = "pcmad",
.module = THIS_MODULE,
.attach = pcmad_attach,
.detach = pcmad_detach,
.board_name = &pcmad_boards[0].name,
.num_names = ARRAY_SIZE(pcmad_boards),
.offset = sizeof(pcmad_boards[0]),
};
module_comedi_driver(pcmad_driver);
MODULE_AUTHOR("Comedi http://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");
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