1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * dac02.c
4 * Comedi driver for DAC02 compatible boards
5 * Copyright (C) 2014 H Hartley Sweeten <hsweeten@visionengravers.com>
6 *
7 * Based on the poc driver
8 * Copyright (C) 2000 Frank Mori Hess <fmhess@users.sourceforge.net>
9 * Copyright (C) 2001 David A. Schleef <ds@schleef.org>
10 *
11 * COMEDI - Linux Control and Measurement Device Interface
12 * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
13 */
14
15 /*
16 * Driver: dac02
17 * Description: Comedi driver for DAC02 compatible boards
18 * Devices: [Keithley Metrabyte] DAC-02 (dac02)
19 * Author: H Hartley Sweeten <hsweeten@visionengravers.com>
20 * Updated: Tue, 11 Mar 2014 11:27:19 -0700
21 * Status: unknown
22 *
23 * Configuration options:
24 * [0] - I/O port base
25 */
26
27 #include <linux/module.h>
28
29 #include "../comedidev.h"
30
31 /*
32 * The output range is selected by jumpering pins on the I/O connector.
33 *
34 * Range Chan # Jumper pins Output
35 * ------------- ------ ------------- -----------------
36 * 0 to 5V 0 21 to 22 24
37 * 1 15 to 16 18
38 * 0 to 10V 0 20 to 22 24
39 * 1 14 to 16 18
40 * +/-5V 0 21 to 22 23
41 * 1 15 to 16 17
42 * +/-10V 0 20 to 22 23
43 * 1 14 to 16 17
44 * 4 to 20mA 0 21 to 22 25
45 * 1 15 to 16 19
46 * AC reference 0 In on pin 22 24 (2-quadrant)
47 * In on pin 22 23 (4-quadrant)
48 * 1 In on pin 16 18 (2-quadrant)
49 * In on pin 16 17 (4-quadrant)
50 */
51 static const struct comedi_lrange das02_ao_ranges = {
52 6, {
53 UNI_RANGE(5),
54 UNI_RANGE(10),
55 BIP_RANGE(5),
56 BIP_RANGE(10),
57 RANGE_mA(4, 20),
58 RANGE_ext(0, 1)
59 }
60 };
61
62 /*
63 * Register I/O map
64 */
65 #define DAC02_AO_LSB(x) (0x00 + ((x) * 2))
66 #define DAC02_AO_MSB(x) (0x01 + ((x) * 2))
67
68 static int dac02_ao_insn_write(struct comedi_device *dev,
69 struct comedi_subdevice *s,
70 struct comedi_insn *insn,
71 unsigned int *data)
72 {
73 unsigned int chan = CR_CHAN(insn->chanspec);
74 unsigned int range = CR_RANGE(insn->chanspec);
75 unsigned int val;
76 int i;
77
78 for (i = 0; i < insn->n; i++) {
79 val = data[i];
80
81 s->readback[chan] = val;
82
83 /*
84 * Unipolar outputs are true binary encoding.
85 * Bipolar outputs are complementary offset binary
86 * (that is, 0 = +full scale, maxdata = -full scale).
87 */
88 if (comedi_range_is_bipolar(s, range))
89 val = s->maxdata - val;
90
91 /*
92 * DACs are double-buffered.
93 * Write LSB then MSB to latch output.
94 */
95 outb((val << 4) & 0xf0, dev->iobase + DAC02_AO_LSB(chan));
96 outb((val >> 4) & 0xff, dev->iobase + DAC02_AO_MSB(chan));
97 }
98
99 return insn->n;
100 }
101
102 static int dac02_attach(struct comedi_device *dev, struct comedi_devconfig *it)
103 {
104 struct comedi_subdevice *s;
105 int ret;
106
107 ret = comedi_request_region(dev, it->options[0], 0x08);
108 if (ret)
109 return ret;
110
111 ret = comedi_alloc_subdevices(dev, 1);
112 if (ret)
113 return ret;
114
115 /* Analog Output subdevice */
116 s = &dev->subdevices[0];
117 s->type = COMEDI_SUBD_AO;
118 s->subdev_flags = SDF_WRITABLE;
119 s->n_chan = 2;
120 s->maxdata = 0x0fff;
121 s->range_table = &das02_ao_ranges;
122 s->insn_write = dac02_ao_insn_write;
123
124 return comedi_alloc_subdev_readback(s);
125 }
126
127 static struct comedi_driver dac02_driver = {
128 .driver_name = "dac02",
129 .module = THIS_MODULE,
130 .attach = dac02_attach,
131 .detach = comedi_legacy_detach,
132 };
133 module_comedi_driver(dac02_driver);
134
135 MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
136 MODULE_DESCRIPTION("Comedi driver for DAC02 compatible boards");
137 MODULE_LICENSE("GPL");