drivers/staging/comedi/range.c

   1 /*
   2     module/range.c
   3     comedi routines for voltage ranges
   4
   5     COMEDI - Linux Control and Measurement Device Interface
   6     Copyright (C) 1997-8 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 #include "comedidev.h"
  25 #include <asm/uaccess.h>
  26
  27 const struct comedi_lrange range_bipolar10 = { 1, {BIP_RANGE(10)} };
  28 const struct comedi_lrange range_bipolar5 = { 1, {BIP_RANGE(5)} };
  29 const struct comedi_lrange range_bipolar2_5 = { 1, {BIP_RANGE(2.5)} };
  30 const struct comedi_lrange range_unipolar10 = { 1, {UNI_RANGE(10)} };
  31 const struct comedi_lrange range_unipolar5 = { 1, {UNI_RANGE(5)} };
  32 const struct comedi_lrange range_unknown = { 1, {{0, 1000000, UNIT_none}} };
  33
  34 /*
  35         COMEDI_RANGEINFO
  36         range information ioctl
  37
  38         arg:
  39                 pointer to rangeinfo structure
  40
  41         reads:
  42                 range info structure
  43
  44         writes:
  45                 n struct comedi_krange structures to rangeinfo->range_ptr
  46 */
  47 int do_rangeinfo_ioctl(struct comedi_device *dev, struct comedi_rangeinfo *arg)
  48 {
  49         struct comedi_rangeinfo it;
  50         int subd, chan;
  51         const struct comedi_lrange *lr;
  52         struct comedi_subdevice *s;
  53
  54         if (copy_from_user(&it, arg, sizeof(struct comedi_rangeinfo)))
  55                 return -EFAULT;
  56         subd = (it.range_type >> 24) & 0xf;
  57         chan = (it.range_type >> 16) & 0xff;
  58
  59         if (!dev->attached)
  60                 return -EINVAL;
  61         if (subd >= dev->n_subdevices)
  62                 return -EINVAL;
  63         s = dev->subdevices + subd;
  64         if (s->range_table) {
  65                 lr = s->range_table;
  66         } else if (s->range_table_list) {
  67                 if (chan >= s->n_chan)
  68                         return -EINVAL;
  69                 lr = s->range_table_list[chan];
  70         } else {
  71                 return -EINVAL;
  72         }
  73
  74         if (RANGE_LENGTH(it.range_type) != lr->length) {
  75                 DPRINTK("wrong length %d should be %d (0x%08x)\n",
  76                         RANGE_LENGTH(it.range_type), lr->length, it.range_type);
  77                 return -EINVAL;
  78         }
  79
  80         if (copy_to_user(it.range_ptr, lr->range,
  81                         sizeof(struct comedi_krange) * lr->length))
  82                 return -EFAULT;
  83
  84         return 0;
  85 }
  86
  87 static int aref_invalid(struct comedi_subdevice *s, unsigned int chanspec)
  88 {
  89         unsigned int aref;
  90
  91         /*  disable reporting invalid arefs... maybe someday */
  92         return 0;
  93
  94         aref = CR_AREF(chanspec);
  95         switch (aref) {
  96         case AREF_DIFF:
  97                 if (s->subdev_flags & SDF_DIFF)
  98                         return 0;
  99                 break;
 100         case AREF_COMMON:
 101                 if (s->subdev_flags & SDF_COMMON)
 102                         return 0;
 103                 break;
 104         case AREF_GROUND:
 105                 if (s->subdev_flags & SDF_GROUND)
 106                         return 0;
 107                 break;
 108         case AREF_OTHER:
 109                 if (s->subdev_flags & SDF_OTHER)
 110                         return 0;
 111                 break;
 112         default:
 113                 break;
 114         }
 115         DPRINTK("subdevice does not support aref %i", aref);
 116         return 1;
 117 }
 118
 119 /*
 120    This function checks each element in a channel/gain list to make
 121    make sure it is valid.
 122 */
 123 int check_chanlist(struct comedi_subdevice *s, int n, unsigned int *chanlist)
 124 {
 125         int i;
 126         int chan;
 127
 128         if (s->range_table) {
 129                 for (i = 0; i < n; i++)
 130                         if (CR_CHAN(chanlist[i]) >= s->n_chan ||
 131                                 CR_RANGE(chanlist[i]) >= s->range_table->length
 132                                 || aref_invalid(s, chanlist[i])) {
 133                                 printk("bad chanlist[%d]=0x%08x n_chan=%d range length=%d\n",
 134                                         i, chanlist[i], s->n_chan,
 135                                         s->range_table->length);
 136 #if 0
 137                                 for (i = 0; i < n; i++)
 138                                         printk("[%d]=0x%08x\n", i, chanlist[i]);
 139 #endif
 140                                 return -EINVAL;
 141                         }
 142         } else if (s->range_table_list) {
 143                 for (i = 0; i < n; i++) {
 144                         chan = CR_CHAN(chanlist[i]);
 145                         if (chan >= s->n_chan ||
 146                                 CR_RANGE(chanlist[i]) >=
 147                                 s->range_table_list[chan]->length
 148                                 || aref_invalid(s, chanlist[i])) {
 149                                 printk("bad chanlist[%d]=0x%08x\n", i,
 150                                         chanlist[i]);
 151                                 return -EINVAL;
 152                         }
 153                 }
 154         } else {
 155                 printk("comedi: (bug) no range type list!\n");
 156                 return -EINVAL;
 157         }
 158         return 0;
 159 }