1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * pcmad.c |
4 | * Hardware driver for Winsystems PCM-A/D12 and PCM-A/D16 |
5 | * |
6 | * COMEDI - Linux Control and Measurement Device Interface |
7 | * Copyright (C) 2000,2001 David A. Schleef <ds@schleef.org> |
8 | */ |
9 | |
10 | /* |
11 | * Driver: pcmad |
12 | * Description: Winsystems PCM-A/D12, PCM-A/D16 |
13 | * Devices: [Winsystems] PCM-A/D12 (pcmad12), PCM-A/D16 (pcmad16) |
14 | * Author: ds |
15 | * Status: untested |
16 | * |
17 | * This driver was written on a bet that I couldn't write a driver |
18 | * in less than 2 hours. I won the bet, but never got paid. =( |
19 | * |
20 | * Configuration options: |
21 | * [0] - I/O port base |
22 | * [1] - IRQ (unused) |
23 | * [2] - Analog input reference (must match jumpers) |
24 | * 0 = single-ended (16 channels) |
25 | * 1 = differential (8 channels) |
26 | * [3] - Analog input encoding (must match jumpers) |
27 | * 0 = straight binary (0-5V input range) |
28 | * 1 = two's complement (+-10V input range) |
29 | */ |
30 | |
31 | #include <linux/module.h> |
32 | #include <linux/comedi/comedidev.h> |
33 | |
34 | #define PCMAD_STATUS 0 |
35 | #define PCMAD_LSB 1 |
36 | #define PCMAD_MSB 2 |
37 | #define PCMAD_CONVERT 1 |
38 | |
39 | struct pcmad_board_struct { |
40 | const char *name; |
41 | unsigned int ai_maxdata; |
42 | }; |
43 | |
44 | static const struct pcmad_board_struct pcmad_boards[] = { |
45 | { |
46 | .name = "pcmad12" , |
47 | .ai_maxdata = 0x0fff, |
48 | }, { |
49 | .name = "pcmad16" , |
50 | .ai_maxdata = 0xffff, |
51 | }, |
52 | }; |
53 | |
54 | static int pcmad_ai_eoc(struct comedi_device *dev, |
55 | struct comedi_subdevice *s, |
56 | struct comedi_insn *insn, |
57 | unsigned long context) |
58 | { |
59 | unsigned int status; |
60 | |
61 | status = inb(port: dev->iobase + PCMAD_STATUS); |
62 | if ((status & 0x3) == 0x3) |
63 | return 0; |
64 | return -EBUSY; |
65 | } |
66 | |
67 | static int pcmad_ai_insn_read(struct comedi_device *dev, |
68 | struct comedi_subdevice *s, |
69 | struct comedi_insn *insn, |
70 | unsigned int *data) |
71 | { |
72 | unsigned int chan = CR_CHAN(insn->chanspec); |
73 | unsigned int range = CR_RANGE(insn->chanspec); |
74 | unsigned int val; |
75 | int ret; |
76 | int i; |
77 | |
78 | for (i = 0; i < insn->n; i++) { |
79 | outb(value: chan, port: dev->iobase + PCMAD_CONVERT); |
80 | |
81 | ret = comedi_timeout(dev, s, insn, cb: pcmad_ai_eoc, context: 0); |
82 | if (ret) |
83 | return ret; |
84 | |
85 | val = inb(port: dev->iobase + PCMAD_LSB) | |
86 | (inb(port: dev->iobase + PCMAD_MSB) << 8); |
87 | |
88 | /* data is shifted on the pcmad12, fix it */ |
89 | if (s->maxdata == 0x0fff) |
90 | val >>= 4; |
91 | |
92 | if (comedi_range_is_bipolar(s, range)) { |
93 | /* munge the two's complement value */ |
94 | val ^= ((s->maxdata + 1) >> 1); |
95 | } |
96 | |
97 | data[i] = val; |
98 | } |
99 | |
100 | return insn->n; |
101 | } |
102 | |
103 | static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it) |
104 | { |
105 | const struct pcmad_board_struct *board = dev->board_ptr; |
106 | struct comedi_subdevice *s; |
107 | int ret; |
108 | |
109 | ret = comedi_request_region(dev, start: it->options[0], len: 0x04); |
110 | if (ret) |
111 | return ret; |
112 | |
113 | ret = comedi_alloc_subdevices(dev, num_subdevices: 1); |
114 | if (ret) |
115 | return ret; |
116 | |
117 | s = &dev->subdevices[0]; |
118 | s->type = COMEDI_SUBD_AI; |
119 | if (it->options[1]) { |
120 | /* 8 differential channels */ |
121 | s->subdev_flags = SDF_READABLE | AREF_DIFF; |
122 | s->n_chan = 8; |
123 | } else { |
124 | /* 16 single-ended channels */ |
125 | s->subdev_flags = SDF_READABLE | AREF_GROUND; |
126 | s->n_chan = 16; |
127 | } |
128 | s->len_chanlist = 1; |
129 | s->maxdata = board->ai_maxdata; |
130 | s->range_table = it->options[2] ? &range_bipolar10 : &range_unipolar5; |
131 | s->insn_read = pcmad_ai_insn_read; |
132 | |
133 | return 0; |
134 | } |
135 | |
136 | static struct comedi_driver pcmad_driver = { |
137 | .driver_name = "pcmad" , |
138 | .module = THIS_MODULE, |
139 | .attach = pcmad_attach, |
140 | .detach = comedi_legacy_detach, |
141 | .board_name = &pcmad_boards[0].name, |
142 | .num_names = ARRAY_SIZE(pcmad_boards), |
143 | .offset = sizeof(pcmad_boards[0]), |
144 | }; |
145 | module_comedi_driver(pcmad_driver); |
146 | |
147 | MODULE_AUTHOR("Comedi https://www.comedi.org" ); |
148 | MODULE_DESCRIPTION("Comedi low-level driver" ); |
149 | MODULE_LICENSE("GPL" ); |
150 | |