drivers/staging/comedi/drivers/dt2817.c

   1 /*
   2     comedi/drivers/dt2817.c
   3     Hardware driver for Data Translation DT2817
   4
   5     COMEDI - Linux Control and Measurement Device Interface
   6     Copyright (C) 1998 David A. Schleef <ds@schleef.org>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23 /*
  24 Driver: dt2817
  25 Description: Data Translation DT2817
  26 Author: ds
  27 Status: complete
  28 Devices: [Data Translation] DT2817 (dt2817)
  29
  30 A very simple digital I/O card.  Four banks of 8 lines, each bank
  31 is configurable for input or output.  One wonders why it takes a
  32 50 page manual to describe this thing.
  33
  34 The driver (which, btw, is much less than 50 pages) has 1 subdevice
  35 with 32 channels, configurable in groups of 8.
  36
  37 Configuration options:
  38   [0] - I/O port base base address
  39 */
  40
  41 #include "../comedidev.h"
  42
  43 #include <linux/ioport.h>
  44
  45 #define DT2817_SIZE 5
  46
  47 #define DT2817_CR 0
  48 #define DT2817_DATA 1
  49
  50 static int dt2817_attach(struct comedi_device * dev, comedi_devconfig * it);
  51 static int dt2817_detach(struct comedi_device * dev);
  52 static struct comedi_driver driver_dt2817 = {
  53       driver_name:"dt2817",
  54       module:THIS_MODULE,
  55       attach:dt2817_attach,
  56       detach:dt2817_detach,
  57 };
  58
  59 COMEDI_INITCLEANUP(driver_dt2817);
  60
  61 static int dt2817_dio_insn_config(struct comedi_device * dev, struct comedi_subdevice * s,
  62         struct comedi_insn * insn, unsigned int * data)
  63 {
  64         int mask;
  65         int chan;
  66         int oe = 0;
  67
  68         if (insn->n != 1)
  69                 return -EINVAL;
  70
  71         chan = CR_CHAN(insn->chanspec);
  72         if (chan < 8) {
  73                 mask = 0xff;
  74         } else if (chan < 16) {
  75                 mask = 0xff00;
  76         } else if (chan < 24) {
  77                 mask = 0xff0000;
  78         } else
  79                 mask = 0xff000000;
  80         if (data[0])
  81                 s->io_bits |= mask;
  82         else
  83                 s->io_bits &= ~mask;
  84
  85         if (s->io_bits & 0x000000ff)
  86                 oe |= 0x1;
  87         if (s->io_bits & 0x0000ff00)
  88                 oe |= 0x2;
  89         if (s->io_bits & 0x00ff0000)
  90                 oe |= 0x4;
  91         if (s->io_bits & 0xff000000)
  92                 oe |= 0x8;
  93
  94         outb(oe, dev->iobase + DT2817_CR);
  95
  96         return 1;
  97 }
  98
  99 static int dt2817_dio_insn_bits(struct comedi_device * dev, struct comedi_subdevice * s,
 100         struct comedi_insn * insn, unsigned int * data)
 101 {
 102         unsigned int changed;
 103
 104         /* It's questionable whether it is more important in
 105          * a driver like this to be deterministic or fast.
 106          * We choose fast. */
 107
 108         if (data[0]) {
 109                 changed = s->state;
 110                 s->state &= ~data[0];
 111                 s->state |= (data[0] & data[1]);
 112                 changed ^= s->state;
 113                 changed &= s->io_bits;
 114                 if (changed & 0x000000ff)
 115                         outb(s->state & 0xff, dev->iobase + DT2817_DATA + 0);
 116                 if (changed & 0x0000ff00)
 117                         outb((s->state >> 8) & 0xff,
 118                                 dev->iobase + DT2817_DATA + 1);
 119                 if (changed & 0x00ff0000)
 120                         outb((s->state >> 16) & 0xff,
 121                                 dev->iobase + DT2817_DATA + 2);
 122                 if (changed & 0xff000000)
 123                         outb((s->state >> 24) & 0xff,
 124                                 dev->iobase + DT2817_DATA + 3);
 125         }
 126         data[1] = inb(dev->iobase + DT2817_DATA + 0);
 127         data[1] |= (inb(dev->iobase + DT2817_DATA + 1) << 8);
 128         data[1] |= (inb(dev->iobase + DT2817_DATA + 2) << 16);
 129         data[1] |= (inb(dev->iobase + DT2817_DATA + 3) << 24);
 130
 131         return 2;
 132 }
 133
 134 static int dt2817_attach(struct comedi_device * dev, comedi_devconfig * it)
 135 {
 136         int ret;
 137         struct comedi_subdevice *s;
 138         unsigned long iobase;
 139
 140         iobase = it->options[0];
 141         printk("comedi%d: dt2817: 0x%04lx ", dev->minor, iobase);
 142         if (!request_region(iobase, DT2817_SIZE, "dt2817")) {
 143                 printk("I/O port conflict\n");
 144                 return -EIO;
 145         }
 146         dev->iobase = iobase;
 147         dev->board_name = "dt2817";
 148
 149         if ((ret = alloc_subdevices(dev, 1)) < 0)
 150                 return ret;
 151
 152         s = dev->subdevices + 0;
 153
 154         s->n_chan = 32;
 155         s->type = COMEDI_SUBD_DIO;
 156         s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
 157         s->range_table = &range_digital;
 158         s->maxdata = 1;
 159         s->insn_bits = dt2817_dio_insn_bits;
 160         s->insn_config = dt2817_dio_insn_config;
 161
 162         s->state = 0;
 163         outb(0, dev->iobase + DT2817_CR);
 164
 165         printk("\n");
 166
 167         return 0;
 168 }
 169
 170 static int dt2817_detach(struct comedi_device * dev)
 171 {
 172         printk("comedi%d: dt2817: remove\n", dev->minor);
 173
 174         if (dev->iobase)
 175                 release_region(dev->iobase, DT2817_SIZE);
 176
 177         return 0;
 178 }