| 1 | /* |
| 2 | * pcmda12.c |
| 3 | * Driver for Winsystems PC-104 based PCM-D/A-12 8-channel AO board. |
| 4 | * |
| 5 | * COMEDI - Linux Control and Measurement Device Interface |
| 6 | * Copyright (C) 2006 Calin A. Culianu <calin@ajvar.org> |
| 7 | * |
| 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. |
| 12 | * |
| 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. |
| 17 | */ |
| 18 | |
| 19 | /* |
| 20 | * Driver: pcmda12 |
| 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 |
| 25 | * Status: works |
| 26 | * |
| 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. |
| 31 | * |
| 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. |
| 35 | * |
| 36 | * Note that the board is not ISA-PNP capable and thus needs the I/O |
| 37 | * port comedi_config parameter. |
| 38 | * |
| 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 |
| 44 | * read command. |
| 45 | * |
| 46 | * Configuration Options: |
| 47 | * [0] - I/O port base address |
| 48 | * [1] - Do Simultaneous Xfer (see description) |
| 49 | */ |
| 50 | |
| 51 | #include <linux/module.h> |
| 52 | #include "../comedidev.h" |
| 53 | |
| 54 | /* AI range is not configurable, it's set by jumpers on the board */ |
| 55 | static const struct comedi_lrange pcmda12_ranges = { |
| 56 | 3, { |
| 57 | UNI_RANGE(5), |
| 58 | UNI_RANGE(10), |
| 59 | BIP_RANGE(5) |
| 60 | } |
| 61 | }; |
| 62 | |
| 63 | struct pcmda12_private { |
| 64 | int simultaneous_xfer_mode; |
| 65 | }; |
| 66 | |
| 67 | static int pcmda12_ao_insn_write(struct comedi_device *dev, |
| 68 | struct comedi_subdevice *s, |
| 69 | struct comedi_insn *insn, |
| 70 | unsigned int *data) |
| 71 | { |
| 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); |
| 76 | int i; |
| 77 | |
| 78 | for (i = 0; i < insn->n; ++i) { |
| 79 | val = data[i]; |
| 80 | outb(val & 0xff, ioreg); |
| 81 | outb((val >> 8) & 0xff, ioreg + 1); |
| 82 | |
| 83 | /* |
| 84 | * Initiate transfer if not in simultaneaous xfer |
| 85 | * mode by reading one of the AO registers. |
| 86 | */ |
| 87 | if (!devpriv->simultaneous_xfer_mode) |
| 88 | inb(ioreg); |
| 89 | } |
| 90 | s->readback[chan] = val; |
| 91 | |
| 92 | return insn->n; |
| 93 | } |
| 94 | |
| 95 | static int pcmda12_ao_insn_read(struct comedi_device *dev, |
| 96 | struct comedi_subdevice *s, |
| 97 | struct comedi_insn *insn, |
| 98 | unsigned int *data) |
| 99 | { |
| 100 | struct pcmda12_private *devpriv = dev->private; |
| 101 | |
| 102 | /* |
| 103 | * Initiate simultaneaous xfer mode by reading one of the |
| 104 | * AO registers. All analog outputs will then be updated. |
| 105 | */ |
| 106 | if (devpriv->simultaneous_xfer_mode) |
| 107 | inb(dev->iobase); |
| 108 | |
| 109 | return comedi_readback_insn_read(dev, s, insn, data); |
| 110 | } |
| 111 | |
| 112 | static void pcmda12_ao_reset(struct comedi_device *dev, |
| 113 | struct comedi_subdevice *s) |
| 114 | { |
| 115 | int i; |
| 116 | |
| 117 | for (i = 0; i < s->n_chan; ++i) { |
| 118 | outb(0, dev->iobase + (i * 2)); |
| 119 | outb(0, dev->iobase + (i * 2) + 1); |
| 120 | } |
| 121 | /* Initiate transfer by reading one of the AO registers. */ |
| 122 | inb(dev->iobase); |
| 123 | } |
| 124 | |
| 125 | static int pcmda12_attach(struct comedi_device *dev, |
| 126 | struct comedi_devconfig *it) |
| 127 | { |
| 128 | struct pcmda12_private *devpriv; |
| 129 | struct comedi_subdevice *s; |
| 130 | int ret; |
| 131 | |
| 132 | ret = comedi_request_region(dev, it->options[0], 0x10); |
| 133 | if (ret) |
| 134 | return ret; |
| 135 | |
| 136 | devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv)); |
| 137 | if (!devpriv) |
| 138 | return -ENOMEM; |
| 139 | |
| 140 | devpriv->simultaneous_xfer_mode = it->options[1]; |
| 141 | |
| 142 | ret = comedi_alloc_subdevices(dev, 1); |
| 143 | if (ret) |
| 144 | return ret; |
| 145 | |
| 146 | s = &dev->subdevices[0]; |
| 147 | s->type = COMEDI_SUBD_AO; |
| 148 | s->subdev_flags = SDF_READABLE | SDF_WRITABLE; |
| 149 | s->n_chan = 8; |
| 150 | s->maxdata = 0x0fff; |
| 151 | s->range_table = &pcmda12_ranges; |
| 152 | s->insn_write = pcmda12_ao_insn_write; |
| 153 | s->insn_read = pcmda12_ao_insn_read; |
| 154 | |
| 155 | ret = comedi_alloc_subdev_readback(s); |
| 156 | if (ret) |
| 157 | return ret; |
| 158 | |
| 159 | pcmda12_ao_reset(dev, s); |
| 160 | |
| 161 | return 0; |
| 162 | } |
| 163 | |
| 164 | static struct comedi_driver pcmda12_driver = { |
| 165 | .driver_name = "pcmda12", |
| 166 | .module = THIS_MODULE, |
| 167 | .attach = pcmda12_attach, |
| 168 | .detach = comedi_legacy_detach, |
| 169 | }; |
| 170 | module_comedi_driver(pcmda12_driver); |
| 171 | |
| 172 | MODULE_AUTHOR("Comedi http://www.comedi.org"); |
| 173 | MODULE_DESCRIPTION("Comedi low-level driver"); |
| 174 | MODULE_LICENSE("GPL"); |