rti802.c

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/*
   comedi/drivers/rti802.c
   Hardware driver for Analog Devices RTI-802 board

   COMEDI - Linux Control and Measurement Device Interface
   Copyright (C) 1999 Anders Blomdell <[email protected]>

   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: rti802
Description: Analog Devices RTI-802
Author: Anders Blomdell <[email protected]>
Devices: [Analog Devices] RTI-802 (rti802)
Status: works

Configuration Options:
    [0] - i/o base
    [1] - unused
    [2] - dac#0  0=two's comp, 1=straight
    [3] - dac#0  0=bipolar, 1=unipolar
    [4] - dac#1 ...
    ...
    [17] - dac#7 ...
*/

#include "../comedidev.h"

#include <linux/ioport.h>

#define RTI802_SIZE 4

#define RTI802_SELECT 0
#define RTI802_DATALOW 1
#define RTI802_DATAHIGH 2

struct rti802_private {
    enum {
        dac_2comp, dac_straight
    } dac_coding[8];
    const struct comedi_lrange *range_type_list[8];
    unsigned int ao_readback[8];
};

#define devpriv ((struct rti802_private *)dev->private)

static int rti802_ao_insn_read(struct comedi_device *dev,
                   struct comedi_subdevice *s,
                   struct comedi_insn *insn, unsigned int *data)
{
    int i;

    for (i = 0; i < insn->n; i++)
        data[i] = devpriv->ao_readback[CR_CHAN(insn->chanspec)];

    return i;
}

static int rti802_ao_insn_write(struct comedi_device *dev,
                struct comedi_subdevice *s,
                struct comedi_insn *insn, unsigned int *data)
{
    int i, d;
    int chan = CR_CHAN(insn->chanspec);

    for (i = 0; i < insn->n; i++) {
        d = devpriv->ao_readback[chan] = data[i];
        if (devpriv->dac_coding[chan] == dac_2comp)
            d ^= 0x800;
        outb(chan, dev->iobase + RTI802_SELECT);
        outb(d & 0xff, dev->iobase + RTI802_DATALOW);
        outb(d >> 8, dev->iobase + RTI802_DATAHIGH);
    }
    return i;
}

static int rti802_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
    struct comedi_subdevice *s;
    int i;
    unsigned long iobase;
    int ret;

    iobase = it->options[0];
    printk(KERN_INFO "comedi%d: rti802: 0x%04lx ", dev->minor, iobase);
    if (!request_region(iobase, RTI802_SIZE, "rti802")) {
        printk(KERN_WARNING "I/O port conflict\n");
        return -EIO;
    }
    dev->iobase = iobase;

    dev->board_name = "rti802";

    if (alloc_private(dev, sizeof(struct rti802_private)))
        return -ENOMEM;

    ret = comedi_alloc_subdevices(dev, 1);
    if (ret)
        return ret;

    s = &dev->subdevices[0];
    /* ao subdevice */
    s->type = COMEDI_SUBD_AO;
    s->subdev_flags = SDF_WRITABLE;
    s->maxdata = 0xfff;
    s->n_chan = 8;
    s->insn_read = rti802_ao_insn_read;
    s->insn_write = rti802_ao_insn_write;
    s->range_table_list = devpriv->range_type_list;

    for (i = 0; i < 8; i++) {
        devpriv->dac_coding[i] = (it->options[3 + 2 * i])
            ? (dac_straight)
            : (dac_2comp);
        devpriv->range_type_list[i] = (it->options[2 + 2 * i])
            ? &range_unipolar10 : &range_bipolar10;
    }

    return 0;
}

static void rti802_detach(struct comedi_device *dev)
{
    if (dev->iobase)
        release_region(dev->iobase, RTI802_SIZE);
}

static struct comedi_driver rti802_driver = {
    .driver_name    = "rti802",
    .module     = THIS_MODULE,
    .attach     = rti802_attach,
    .detach     = rti802_detach,
};
module_comedi_driver(rti802_driver);

MODULE_AUTHOR("Comedi http://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");