3 * Driver for Winsystems PC-104 based PCM-D/A-12 8-channel AO board.
5 * COMEDI - Linux Control and Measurement Device Interface
6 * Copyright (C) 2006 Calin A. Culianu <calin@ajvar.org>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
21 * Description: A driver for the Winsystems PCM-D/A-12
22 * Devices: [Winsystems] PCM-D/A-12 (pcmda12)
23 * Author: Calin Culianu <calin@ajvar.org>
24 * Updated: Fri, 13 Jan 2006 12:01:01 -0500
27 * A driver for the relatively straightforward-to-program PCM-D/A-12.
28 * This board doesn't support commands, and the only way to set its
29 * analog output range is to jumper the board. As such,
30 * comedi_data_write() ignores the range value specified.
32 * The board uses 16 consecutive I/O addresses starting at the I/O port
33 * base address. Each address corresponds to the LSB then MSB of a
34 * particular channel from 0-7.
36 * Note that the board is not ISA-PNP capable and thus needs the I/O
37 * port comedi_config parameter.
39 * Note that passing a nonzero value as the second config option will
40 * enable "simultaneous xfer" mode for this board, in which AO writes
41 * will not take effect until a subsequent read of any AO channel. This
42 * is so that one can speed up programming by preloading all AO registers
43 * with values before simultaneously setting them to take effect with one
46 * Configuration Options:
47 * [0] - I/O port base address
48 * [1] - Do Simultaneous Xfer (see description)
51 #include <linux/module.h>
52 #include "../comedidev.h"
54 /* AI range is not configurable, it's set by jumpers on the board */
55 static const struct comedi_lrange pcmda12_ranges
= {
63 struct pcmda12_private
{
64 int simultaneous_xfer_mode
;
67 static int pcmda12_ao_insn_write(struct comedi_device
*dev
,
68 struct comedi_subdevice
*s
,
69 struct comedi_insn
*insn
,
72 struct pcmda12_private
*devpriv
= dev
->private;
73 unsigned int chan
= CR_CHAN(insn
->chanspec
);
74 unsigned int val
= s
->readback
[chan
];
75 unsigned long ioreg
= dev
->iobase
+ (chan
* 2);
78 for (i
= 0; i
< insn
->n
; ++i
) {
80 outb(val
& 0xff, ioreg
);
81 outb((val
>> 8) & 0xff, ioreg
+ 1);
84 * Initiate transfer if not in simultaneaous xfer
85 * mode by reading one of the AO registers.
87 if (!devpriv
->simultaneous_xfer_mode
)
90 s
->readback
[chan
] = val
;
95 static int pcmda12_ao_insn_read(struct comedi_device
*dev
,
96 struct comedi_subdevice
*s
,
97 struct comedi_insn
*insn
,
100 struct pcmda12_private
*devpriv
= dev
->private;
103 * Initiate simultaneaous xfer mode by reading one of the
104 * AO registers. All analog outputs will then be updated.
106 if (devpriv
->simultaneous_xfer_mode
)
109 return comedi_readback_insn_read(dev
, s
, insn
, data
);
112 static void pcmda12_ao_reset(struct comedi_device
*dev
,
113 struct comedi_subdevice
*s
)
117 for (i
= 0; i
< s
->n_chan
; ++i
) {
118 outb(0, dev
->iobase
+ (i
* 2));
119 outb(0, dev
->iobase
+ (i
* 2) + 1);
121 /* Initiate transfer by reading one of the AO registers. */
125 static int pcmda12_attach(struct comedi_device
*dev
,
126 struct comedi_devconfig
*it
)
128 struct pcmda12_private
*devpriv
;
129 struct comedi_subdevice
*s
;
132 ret
= comedi_request_region(dev
, it
->options
[0], 0x10);
136 devpriv
= comedi_alloc_devpriv(dev
, sizeof(*devpriv
));
140 devpriv
->simultaneous_xfer_mode
= it
->options
[1];
142 ret
= comedi_alloc_subdevices(dev
, 1);
146 s
= &dev
->subdevices
[0];
147 s
->type
= COMEDI_SUBD_AO
;
148 s
->subdev_flags
= SDF_READABLE
| SDF_WRITABLE
;
151 s
->range_table
= &pcmda12_ranges
;
152 s
->insn_write
= pcmda12_ao_insn_write
;
153 s
->insn_read
= pcmda12_ao_insn_read
;
155 ret
= comedi_alloc_subdev_readback(s
);
159 pcmda12_ao_reset(dev
, s
);
164 static struct comedi_driver pcmda12_driver
= {
165 .driver_name
= "pcmda12",
166 .module
= THIS_MODULE
,
167 .attach
= pcmda12_attach
,
168 .detach
= comedi_legacy_detach
,
170 module_comedi_driver(pcmda12_driver
);
172 MODULE_AUTHOR("Comedi http://www.comedi.org");
173 MODULE_DESCRIPTION("Comedi low-level driver");
174 MODULE_LICENSE("GPL");