1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * pcmda12.c
4 * Driver for Winsystems PC-104 based PCM-D/A-12 8-channel AO board.
5 *
6 * COMEDI - Linux Control and Measurement Device Interface
7 * Copyright (C) 2006 Calin A. Culianu <calin@ajvar.org>
8 */
9
10/*
11 * Driver: pcmda12
12 * Description: A driver for the Winsystems PCM-D/A-12
13 * Devices: [Winsystems] PCM-D/A-12 (pcmda12)
14 * Author: Calin Culianu <calin@ajvar.org>
15 * Updated: Fri, 13 Jan 2006 12:01:01 -0500
16 * Status: works
17 *
18 * A driver for the relatively straightforward-to-program PCM-D/A-12.
19 * This board doesn't support commands, and the only way to set its
20 * analog output range is to jumper the board. As such,
21 * comedi_data_write() ignores the range value specified.
22 *
23 * The board uses 16 consecutive I/O addresses starting at the I/O port
24 * base address. Each address corresponds to the LSB then MSB of a
25 * particular channel from 0-7.
26 *
27 * Note that the board is not ISA-PNP capable and thus needs the I/O
28 * port comedi_config parameter.
29 *
30 * Note that passing a nonzero value as the second config option will
31 * enable "simultaneous xfer" mode for this board, in which AO writes
32 * will not take effect until a subsequent read of any AO channel. This
33 * is so that one can speed up programming by preloading all AO registers
34 * with values before simultaneously setting them to take effect with one
35 * read command.
36 *
37 * Configuration Options:
38 *   [0] - I/O port base address
39 *   [1] - Do Simultaneous Xfer (see description)
40 */
41
42#include <linux/module.h>
43#include <linux/comedi/comedidev.h>
44
45/* AI range is not configurable, it's set by jumpers on the board */
46static const struct comedi_lrange pcmda12_ranges = {
47	3, {
48		UNI_RANGE(5),
49		UNI_RANGE(10),
50		BIP_RANGE(5)
51	}
52};
53
54struct pcmda12_private {
55	int simultaneous_xfer_mode;
56};
57
58static int pcmda12_ao_insn_write(struct comedi_device *dev,
59				 struct comedi_subdevice *s,
60				 struct comedi_insn *insn,
61				 unsigned int *data)
62{
63	struct pcmda12_private *devpriv = dev->private;
64	unsigned int chan = CR_CHAN(insn->chanspec);
65	unsigned int val = s->readback[chan];
66	unsigned long ioreg = dev->iobase + (chan * 2);
67	int i;
68
69	for (i = 0; i < insn->n; ++i) {
70		val = data[i];
71		outb(val & 0xff, ioreg);
72		outb((val >> 8) & 0xff, ioreg + 1);
73
74		/*
75		 * Initiate transfer if not in simultaneaous xfer
76		 * mode by reading one of the AO registers.
77		 */
78		if (!devpriv->simultaneous_xfer_mode)
79			inb(ioreg);
80	}
81	s->readback[chan] = val;
82
83	return insn->n;
84}
85
86static int pcmda12_ao_insn_read(struct comedi_device *dev,
87				struct comedi_subdevice *s,
88				struct comedi_insn *insn,
89				unsigned int *data)
90{
91	struct pcmda12_private *devpriv = dev->private;
92
93	/*
94	 * Initiate simultaneaous xfer mode by reading one of the
95	 * AO registers. All analog outputs will then be updated.
96	 */
97	if (devpriv->simultaneous_xfer_mode)
98		inb(dev->iobase);
99
100	return comedi_readback_insn_read(dev, s, insn, data);
101}
102
103static void pcmda12_ao_reset(struct comedi_device *dev,
104			     struct comedi_subdevice *s)
105{
106	int i;
107
108	for (i = 0; i < s->n_chan; ++i) {
109		outb(0, dev->iobase + (i * 2));
110		outb(0, dev->iobase + (i * 2) + 1);
111	}
112	/* Initiate transfer by reading one of the AO registers. */
113	inb(dev->iobase);
114}
115
116static int pcmda12_attach(struct comedi_device *dev,
117			  struct comedi_devconfig *it)
118{
119	struct pcmda12_private *devpriv;
120	struct comedi_subdevice *s;
121	int ret;
122
123	ret = comedi_request_region(dev, it->options[0], 0x10);
124	if (ret)
125		return ret;
126
127	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
128	if (!devpriv)
129		return -ENOMEM;
130
131	devpriv->simultaneous_xfer_mode = it->options[1];
132
133	ret = comedi_alloc_subdevices(dev, 1);
134	if (ret)
135		return ret;
136
137	s = &dev->subdevices[0];
138	s->type		= COMEDI_SUBD_AO;
139	s->subdev_flags	= SDF_READABLE | SDF_WRITABLE;
140	s->n_chan	= 8;
141	s->maxdata	= 0x0fff;
142	s->range_table	= &pcmda12_ranges;
143	s->insn_write	= pcmda12_ao_insn_write;
144	s->insn_read	= pcmda12_ao_insn_read;
145
146	ret = comedi_alloc_subdev_readback(s);
147	if (ret)
148		return ret;
149
150	pcmda12_ao_reset(dev, s);
151
152	return 0;
153}
154
155static struct comedi_driver pcmda12_driver = {
156	.driver_name	= "pcmda12",
157	.module		= THIS_MODULE,
158	.attach		= pcmda12_attach,
159	.detach		= comedi_legacy_detach,
160};
161module_comedi_driver(pcmda12_driver);
162
163MODULE_AUTHOR("Comedi https://www.comedi.org");
164MODULE_DESCRIPTION("Comedi low-level driver");
165MODULE_LICENSE("GPL");
166