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

Archive Download this file



interactive