1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * comedi/drivers/dt2817.c
4 * Hardware driver for Data Translation DT2817
5 *
6 * COMEDI - Linux Control and Measurement Device Interface
7 * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
8 */
9/*
10 * Driver: dt2817
11 * Description: Data Translation DT2817
12 * Author: ds
13 * Status: complete
14 * Devices: [Data Translation] DT2817 (dt2817)
15 *
16 * A very simple digital I/O card. Four banks of 8 lines, each bank
17 * is configurable for input or output. One wonders why it takes a
18 * 50 page manual to describe this thing.
19 *
20 * The driver (which, btw, is much less than 50 pages) has 1 subdevice
21 * with 32 channels, configurable in groups of 8.
22 *
23 * Configuration options:
24 * [0] - I/O port base base address
25 */
26
27#include <linux/module.h>
28#include <linux/comedi/comedidev.h>
29
30#define DT2817_CR 0
31#define DT2817_DATA 1
32
33static int dt2817_dio_insn_config(struct comedi_device *dev,
34 struct comedi_subdevice *s,
35 struct comedi_insn *insn,
36 unsigned int *data)
37{
38 unsigned int chan = CR_CHAN(insn->chanspec);
39 unsigned int oe = 0;
40 unsigned int mask;
41 int ret;
42
43 if (chan < 8)
44 mask = 0x000000ff;
45 else if (chan < 16)
46 mask = 0x0000ff00;
47 else if (chan < 24)
48 mask = 0x00ff0000;
49 else
50 mask = 0xff000000;
51
52 ret = comedi_dio_insn_config(dev, s, insn, data, mask);
53 if (ret)
54 return ret;
55
56 if (s->io_bits & 0x000000ff)
57 oe |= 0x1;
58 if (s->io_bits & 0x0000ff00)
59 oe |= 0x2;
60 if (s->io_bits & 0x00ff0000)
61 oe |= 0x4;
62 if (s->io_bits & 0xff000000)
63 oe |= 0x8;
64
65 outb(value: oe, port: dev->iobase + DT2817_CR);
66
67 return insn->n;
68}
69
70static int dt2817_dio_insn_bits(struct comedi_device *dev,
71 struct comedi_subdevice *s,
72 struct comedi_insn *insn,
73 unsigned int *data)
74{
75 unsigned long iobase = dev->iobase + DT2817_DATA;
76 unsigned int mask;
77 unsigned int val;
78
79 mask = comedi_dio_update_state(s, data);
80 if (mask) {
81 if (mask & 0x000000ff)
82 outb(value: s->state & 0xff, port: iobase + 0);
83 if (mask & 0x0000ff00)
84 outb(value: (s->state >> 8) & 0xff, port: iobase + 1);
85 if (mask & 0x00ff0000)
86 outb(value: (s->state >> 16) & 0xff, port: iobase + 2);
87 if (mask & 0xff000000)
88 outb(value: (s->state >> 24) & 0xff, port: iobase + 3);
89 }
90
91 val = inb(port: iobase + 0);
92 val |= (inb(port: iobase + 1) << 8);
93 val |= (inb(port: iobase + 2) << 16);
94 val |= (inb(port: iobase + 3) << 24);
95
96 data[1] = val;
97
98 return insn->n;
99}
100
101static int dt2817_attach(struct comedi_device *dev, struct comedi_devconfig *it)
102{
103 int ret;
104 struct comedi_subdevice *s;
105
106 ret = comedi_request_region(dev, start: it->options[0], len: 0x5);
107 if (ret)
108 return ret;
109
110 ret = comedi_alloc_subdevices(dev, num_subdevices: 1);
111 if (ret)
112 return ret;
113
114 s = &dev->subdevices[0];
115
116 s->n_chan = 32;
117 s->type = COMEDI_SUBD_DIO;
118 s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
119 s->range_table = &range_digital;
120 s->maxdata = 1;
121 s->insn_bits = dt2817_dio_insn_bits;
122 s->insn_config = dt2817_dio_insn_config;
123
124 s->state = 0;
125 outb(value: 0, port: dev->iobase + DT2817_CR);
126
127 return 0;
128}
129
130static struct comedi_driver dt2817_driver = {
131 .driver_name = "dt2817",
132 .module = THIS_MODULE,
133 .attach = dt2817_attach,
134 .detach = comedi_legacy_detach,
135};
136module_comedi_driver(dt2817_driver);
137
138MODULE_AUTHOR("Comedi https://www.comedi.org");
139MODULE_DESCRIPTION("Comedi low-level driver");
140MODULE_LICENSE("GPL");
141

source code of linux/drivers/comedi/drivers/dt2817.c