LXR linux/drivers/staging/comedi/drivers/pcmda12.c

   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 "../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