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 */ 55static const struct comedi_lrange pcmda12_ranges = { 56 3, { 57 UNI_RANGE(5), 58 UNI_RANGE(10), 59 BIP_RANGE(5) 60 } 61}; 62 63struct pcmda12_private { 64 int simultaneous_xfer_mode; 65}; 66 67static 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 95static 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 112static 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 125static 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 164static struct comedi_driver pcmda12_driver = { 165 .driver_name = "pcmda12", 166 .module = THIS_MODULE, 167 .attach = pcmda12_attach, 168 .detach = comedi_legacy_detach, 169}; 170module_comedi_driver(pcmda12_driver); 171 172MODULE_AUTHOR("Comedi http://www.comedi.org"); 173MODULE_DESCRIPTION("Comedi low-level driver"); 174MODULE_LICENSE("GPL"); 175