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 "../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
pcmad_ai_eoc(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned long context)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(dev->iobase + PCMAD_STATUS);
62 if ((status & 0x3) == 0x3)
63 return 0;
64 return -EBUSY;
65 }
66
pcmad_ai_insn_read(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)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(chan, dev->iobase + PCMAD_CONVERT);
80
81 ret = comedi_timeout(dev, s, insn, pcmad_ai_eoc, 0);
82 if (ret)
83 return ret;
84
85 val = inb(dev->iobase + PCMAD_LSB) |
86 (inb(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
pcmad_attach(struct comedi_device * dev,struct comedi_devconfig * it)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, it->options[0], 0x04);
110 if (ret)
111 return ret;
112
113 ret = comedi_alloc_subdevices(dev, 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