1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * comedi/range.c |
4 | * comedi routines for voltage ranges |
5 | * |
6 | * COMEDI - Linux Control and Measurement Device Interface |
7 | * Copyright (C) 1997-8 David A. Schleef <ds@schleef.org> |
8 | */ |
9 | |
10 | #include <linux/uaccess.h> |
11 | #include <linux/comedi/comedidev.h> |
12 | #include "comedi_internal.h" |
13 | |
14 | const struct comedi_lrange range_bipolar10 = { 1, {BIP_RANGE(10)} }; |
15 | EXPORT_SYMBOL_GPL(range_bipolar10); |
16 | const struct comedi_lrange range_bipolar5 = { 1, {BIP_RANGE(5)} }; |
17 | EXPORT_SYMBOL_GPL(range_bipolar5); |
18 | const struct comedi_lrange range_bipolar2_5 = { 1, {BIP_RANGE(2.5)} }; |
19 | EXPORT_SYMBOL_GPL(range_bipolar2_5); |
20 | const struct comedi_lrange range_unipolar10 = { 1, {UNI_RANGE(10)} }; |
21 | EXPORT_SYMBOL_GPL(range_unipolar10); |
22 | const struct comedi_lrange range_unipolar5 = { 1, {UNI_RANGE(5)} }; |
23 | EXPORT_SYMBOL_GPL(range_unipolar5); |
24 | const struct comedi_lrange range_unipolar2_5 = { 1, {UNI_RANGE(2.5)} }; |
25 | EXPORT_SYMBOL_GPL(range_unipolar2_5); |
26 | const struct comedi_lrange range_0_20mA = { 1, {RANGE_mA(0, 20)} }; |
27 | EXPORT_SYMBOL_GPL(range_0_20mA); |
28 | const struct comedi_lrange range_4_20mA = { 1, {RANGE_mA(4, 20)} }; |
29 | EXPORT_SYMBOL_GPL(range_4_20mA); |
30 | const struct comedi_lrange range_0_32mA = { 1, {RANGE_mA(0, 32)} }; |
31 | EXPORT_SYMBOL_GPL(range_0_32mA); |
32 | const struct comedi_lrange range_unknown = { 1, {{0, 1000000, UNIT_none} } }; |
33 | EXPORT_SYMBOL_GPL(range_unknown); |
34 | |
35 | /* |
36 | * COMEDI_RANGEINFO ioctl |
37 | * range information |
38 | * |
39 | * arg: |
40 | * pointer to comedi_rangeinfo structure |
41 | * |
42 | * reads: |
43 | * comedi_rangeinfo structure |
44 | * |
45 | * writes: |
46 | * array of comedi_krange structures to rangeinfo->range_ptr pointer |
47 | */ |
48 | int do_rangeinfo_ioctl(struct comedi_device *dev, |
49 | struct comedi_rangeinfo *it) |
50 | { |
51 | int subd, chan; |
52 | const struct comedi_lrange *lr; |
53 | struct comedi_subdevice *s; |
54 | |
55 | subd = (it->range_type >> 24) & 0xf; |
56 | chan = (it->range_type >> 16) & 0xff; |
57 | |
58 | if (!dev->attached) |
59 | return -EINVAL; |
60 | if (subd >= dev->n_subdevices) |
61 | return -EINVAL; |
62 | s = &dev->subdevices[subd]; |
63 | if (s->range_table) { |
64 | lr = s->range_table; |
65 | } else if (s->range_table_list) { |
66 | if (chan >= s->n_chan) |
67 | return -EINVAL; |
68 | lr = s->range_table_list[chan]; |
69 | } else { |
70 | return -EINVAL; |
71 | } |
72 | |
73 | if (RANGE_LENGTH(it->range_type) != lr->length) { |
74 | dev_dbg(dev->class_dev, |
75 | "wrong length %d should be %d (0x%08x)\n" , |
76 | RANGE_LENGTH(it->range_type), |
77 | lr->length, it->range_type); |
78 | return -EINVAL; |
79 | } |
80 | |
81 | if (copy_to_user(to: it->range_ptr, from: lr->range, |
82 | n: sizeof(struct comedi_krange) * lr->length)) |
83 | return -EFAULT; |
84 | |
85 | return 0; |
86 | } |
87 | |
88 | /** |
89 | * comedi_check_chanlist() - Validate each element in a chanlist. |
90 | * @s: comedi_subdevice struct |
91 | * @n: number of elements in the chanlist |
92 | * @chanlist: the chanlist to validate |
93 | * |
94 | * Each element consists of a channel number, a range index, an analog |
95 | * reference type and some flags, all packed into an unsigned int. |
96 | * |
97 | * This checks that the channel number and range index are supported by |
98 | * the comedi subdevice. It does not check whether the analog reference |
99 | * type and the flags are supported. Drivers that care should check those |
100 | * themselves. |
101 | * |
102 | * Return: %0 if all @chanlist elements are valid (success), |
103 | * %-EINVAL if one or more elements are invalid. |
104 | */ |
105 | int comedi_check_chanlist(struct comedi_subdevice *s, int n, |
106 | unsigned int *chanlist) |
107 | { |
108 | struct comedi_device *dev = s->device; |
109 | unsigned int chanspec; |
110 | int chan, range_len, i; |
111 | |
112 | for (i = 0; i < n; i++) { |
113 | chanspec = chanlist[i]; |
114 | chan = CR_CHAN(chanspec); |
115 | if (s->range_table) |
116 | range_len = s->range_table->length; |
117 | else if (s->range_table_list && chan < s->n_chan) |
118 | range_len = s->range_table_list[chan]->length; |
119 | else |
120 | range_len = 0; |
121 | if (chan >= s->n_chan || |
122 | CR_RANGE(chanspec) >= range_len) { |
123 | dev_warn(dev->class_dev, |
124 | "bad chanlist[%d]=0x%08x chan=%d range length=%d\n" , |
125 | i, chanspec, chan, range_len); |
126 | return -EINVAL; |
127 | } |
128 | } |
129 | return 0; |
130 | } |
131 | EXPORT_SYMBOL_GPL(comedi_check_chanlist); |
132 | |