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 <linux/uaccess.h>
  25 #include "comedidev.h"
  26 #include "comedi_internal.h"
  27
  28 const struct comedi_lrange range_bipolar10 = { 1, {BIP_RANGE(10)} };
  29 EXPORT_SYMBOL_GPL(range_bipolar10);
  30 const struct comedi_lrange range_bipolar5 = { 1, {BIP_RANGE(5)} };
  31 EXPORT_SYMBOL_GPL(range_bipolar5);
  32 const struct comedi_lrange range_bipolar2_5 = { 1, {BIP_RANGE(2.5)} };
  33 EXPORT_SYMBOL_GPL(range_bipolar2_5);
  34 const struct comedi_lrange range_unipolar10 = { 1, {UNI_RANGE(10)} };
  35 EXPORT_SYMBOL_GPL(range_unipolar10);
  36 const struct comedi_lrange range_unipolar5 = { 1, {UNI_RANGE(5)} };
  37 EXPORT_SYMBOL_GPL(range_unipolar5);
  38 const struct comedi_lrange range_unipolar2_5 = { 1, {UNI_RANGE(2.5)} };
  39 EXPORT_SYMBOL_GPL(range_unipolar2_5);
  40 const struct comedi_lrange range_0_20mA = { 1, {RANGE_mA(0, 20)} };
  41 EXPORT_SYMBOL_GPL(range_0_20mA);
  42 const struct comedi_lrange range_4_20mA = { 1, {RANGE_mA(4, 20)} };
  43 EXPORT_SYMBOL_GPL(range_4_20mA);
  44 const struct comedi_lrange range_0_32mA = { 1, {RANGE_mA(0, 32)} };
  45 EXPORT_SYMBOL_GPL(range_0_32mA);
  46 const struct comedi_lrange range_unknown = { 1, {{0, 1000000, UNIT_none} } };
  47 EXPORT_SYMBOL_GPL(range_unknown);
  48
  49 /*
  50         COMEDI_RANGEINFO
  51         range information ioctl
  52
  53         arg:
  54                 pointer to rangeinfo structure
  55
  56         reads:
  57                 range info structure
  58
  59         writes:
  60                 n struct comedi_krange structures to rangeinfo->range_ptr
  61 */
  62 int do_rangeinfo_ioctl(struct comedi_device *dev,
  63                        struct comedi_rangeinfo __user *arg)
  64 {
  65         struct comedi_rangeinfo it;
  66         int subd, chan;
  67         const struct comedi_lrange *lr;
  68         struct comedi_subdevice *s;
  69
  70         if (copy_from_user(&it, arg, sizeof(struct comedi_rangeinfo)))
  71                 return -EFAULT;
  72         subd = (it.range_type >> 24) & 0xf;
  73         chan = (it.range_type >> 16) & 0xff;
  74
  75         if (!dev->attached)
  76                 return -EINVAL;
  77         if (subd >= dev->n_subdevices)
  78                 return -EINVAL;
  79         s = &dev->subdevices[subd];
  80         if (s->range_table) {
  81                 lr = s->range_table;
  82         } else if (s->range_table_list) {
  83                 if (chan >= s->n_chan)
  84                         return -EINVAL;
  85                 lr = s->range_table_list[chan];
  86         } else {
  87                 return -EINVAL;
  88         }
  89
  90         if (RANGE_LENGTH(it.range_type) != lr->length) {
  91                 DPRINTK("wrong length %d should be %d (0x%08x)\n",
  92                         RANGE_LENGTH(it.range_type), lr->length, it.range_type);
  93                 return -EINVAL;
  94         }
  95
  96         if (copy_to_user(it.range_ptr, lr->range,
  97                          sizeof(struct comedi_krange) * lr->length))
  98                 return -EFAULT;
  99
 100         return 0;
 101 }
 102
 103 static int aref_invalid(struct comedi_subdevice *s, unsigned int chanspec)
 104 {
 105         unsigned int aref;
 106
 107         /*  disable reporting invalid arefs... maybe someday */
 108         return 0;
 109
 110         aref = CR_AREF(chanspec);
 111         switch (aref) {
 112         case AREF_DIFF:
 113                 if (s->subdev_flags & SDF_DIFF)
 114                         return 0;
 115                 break;
 116         case AREF_COMMON:
 117                 if (s->subdev_flags & SDF_COMMON)
 118                         return 0;
 119                 break;
 120         case AREF_GROUND:
 121                 if (s->subdev_flags & SDF_GROUND)
 122                         return 0;
 123                 break;
 124         case AREF_OTHER:
 125                 if (s->subdev_flags & SDF_OTHER)
 126                         return 0;
 127                 break;
 128         default:
 129                 break;
 130         }
 131         DPRINTK("subdevice does not support aref %i", aref);
 132         return 1;
 133 }
 134
 135 /*
 136    This function checks each element in a channel/gain list to make
 137    make sure it is valid.
 138 */
 139 int comedi_check_chanlist(struct comedi_subdevice *s, int n,
 140                           unsigned int *chanlist)
 141 {
 142         struct comedi_device *dev = s->device;
 143         int i;
 144         int chan;
 145
 146         if (s->range_table) {
 147                 for (i = 0; i < n; i++)
 148                         if (CR_CHAN(chanlist[i]) >= s->n_chan ||
 149                             CR_RANGE(chanlist[i]) >= s->range_table->length
 150                             || aref_invalid(s, chanlist[i])) {
 151                                 dev_warn(dev->class_dev,
 152                                          "bad chanlist[%d]=0x%08x in_chan=%d range length=%d\n",
 153                                          i, chanlist[i], s->n_chan,
 154                                          s->range_table->length);
 155                                 return -EINVAL;
 156                         }
 157         } else if (s->range_table_list) {
 158                 for (i = 0; i < n; i++) {
 159                         chan = CR_CHAN(chanlist[i]);
 160                         if (chan >= s->n_chan ||
 161                             CR_RANGE(chanlist[i]) >=
 162                             s->range_table_list[chan]->length
 163                             || aref_invalid(s, chanlist[i])) {
 164                                 dev_warn(dev->class_dev,
 165                                          "bad chanlist[%d]=0x%08x\n",
 166                                          i, chanlist[i]);
 167                                 return -EINVAL;
 168                         }
 169                 }
 170         } else {
 171                 dev_err(dev->class_dev, "(bug) no range type list!\n");
 172                 return -EINVAL;
 173         }
 174         return 0;
 175 }
 176 EXPORT_SYMBOL_GPL(comedi_check_chanlist);