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#include <linux/comedi/comedidev.h>
29
30/*
31 * The output range is selected by jumpering pins on the I/O connector.
32 *
33 *	    Range      Chan #   Jumper pins        Output
34 *	-------------  ------  -------------  -----------------
35 *	   0 to 5V       0        21 to 22      24
36 *	                 1        15 to 16      18
37 *	   0 to 10V      0        20 to 22      24
38 *	                 1        14 to 16      18
39 *	    +/-5V        0        21 to 22      23
40 *	                 1        15 to 16      17
41 *	    +/-10V       0        20 to 22      23
42 *	                 1        14 to 16      17
43 *	  4 to 20mA      0        21 to 22      25
44 *	                 1        15 to 16      19
45 *	AC reference     0      In on pin 22    24 (2-quadrant)
46 *	                        In on pin 22    23 (4-quadrant)
47 *	                 1      In on pin 16    18 (2-quadrant)
48 *	                        In on pin 16    17 (4-quadrant)
49 */
50static const struct comedi_lrange das02_ao_ranges = {
51	6, {
52		UNI_RANGE(5),
53		UNI_RANGE(10),
54		BIP_RANGE(5),
55		BIP_RANGE(10),
56		RANGE_mA(4, 20),
57		RANGE_ext(0, 1)
58	}
59};
60
61/*
62 * Register I/O map
63 */
64#define DAC02_AO_LSB(x)		(0x00 + ((x) * 2))
65#define DAC02_AO_MSB(x)		(0x01 + ((x) * 2))
66
67static int dac02_ao_insn_write(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 i;
76
77	for (i = 0; i < insn->n; i++) {
78		val = data[i];
79
80		s->readback[chan] = val;
81
82		/*
83		 * Unipolar outputs are true binary encoding.
84		 * Bipolar outputs are complementary offset binary
85		 * (that is, 0 = +full scale, maxdata = -full scale).
86		 */
87		if (comedi_range_is_bipolar(s, range))
88			val = s->maxdata - val;
89
90		/*
91		 * DACs are double-buffered.
92		 * Write LSB then MSB to latch output.
93		 */
94		outb((val << 4) & 0xf0, dev->iobase + DAC02_AO_LSB(chan));
95		outb((val >> 4) & 0xff, dev->iobase + DAC02_AO_MSB(chan));
96	}
97
98	return insn->n;
99}
100
101static int dac02_attach(struct comedi_device *dev, struct comedi_devconfig *it)
102{
103	struct comedi_subdevice *s;
104	int ret;
105
106	ret = comedi_request_region(dev, it->options[0], 0x08);
107	if (ret)
108		return ret;
109
110	ret = comedi_alloc_subdevices(dev, 1);
111	if (ret)
112		return ret;
113
114	/* Analog Output subdevice */
115	s = &dev->subdevices[0];
116	s->type		= COMEDI_SUBD_AO;
117	s->subdev_flags	= SDF_WRITABLE;
118	s->n_chan	= 2;
119	s->maxdata	= 0x0fff;
120	s->range_table	= &das02_ao_ranges;
121	s->insn_write	= dac02_ao_insn_write;
122
123	return comedi_alloc_subdev_readback(s);
124}
125
126static struct comedi_driver dac02_driver = {
127	.driver_name	= "dac02",
128	.module		= THIS_MODULE,
129	.attach		= dac02_attach,
130	.detach		= comedi_legacy_detach,
131};
132module_comedi_driver(dac02_driver);
133
134MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
135MODULE_DESCRIPTION("Comedi driver for DAC02 compatible boards");
136MODULE_LICENSE("GPL");
137