--- /dev/null
+/*
+ comedi/drivers/comedi_parport.c
+ hardware driver for standard parallel port
+
+ COMEDI - Linux Control and Measurement Device Interface
+ Copyright (C) 1998,2001 David A. Schleef <ds@schleef.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+/*
+Driver: comedi_parport
+Description: Standard PC parallel port
+Author: ds
+Status: works in immediate mode
+Devices: [standard] parallel port (comedi_parport)
+Updated: Tue, 30 Apr 2002 21:11:45 -0700
+
+A cheap and easy way to get a few more digital I/O lines. Steal
+additional parallel ports from old computers or your neighbors'
+computers.
+
+Option list:
+ 0: I/O port base for the parallel port.
+ 1: IRQ
+
+Parallel Port Lines:
+
+pin subdev chan aka
+--- ------ ---- ---
+1 2 0 strobe
+2 0 0 data 0
+3 0 1 data 1
+4 0 2 data 2
+5 0 3 data 3
+6 0 4 data 4
+7 0 5 data 5
+8 0 6 data 6
+9 0 7 data 7
+10 1 3 acknowledge
+11 1 4 busy
+12 1 2 output
+13 1 1 printer selected
+14 2 1 auto LF
+15 1 0 error
+16 2 2 init
+17 2 3 select printer
+18-25 ground
+
+Notes:
+
+Subdevices 0 is digital I/O, subdevice 1 is digital input, and
+subdevice 2 is digital output. Unlike other Comedi devices,
+subdevice 0 defaults to output.
+
+Pins 13 and 14 are inverted once by Comedi and once by the
+hardware, thus cancelling the effect.
+
+Pin 1 is a strobe, thus acts like one. There's no way in software
+to change this, at least on a standard parallel port.
+
+Subdevice 3 pretends to be a digital input subdevice, but it always
+returns 0 when read. However, if you run a command with
+scan_begin_src=TRIG_EXT, it uses pin 10 as a external triggering
+pin, which can be used to wake up tasks.
+*/
+/*
+ see http://www.beyondlogic.org/ for information.
+ or http://www.linux-magazin.de/ausgabe/1999/10/IO/io.html
+ */
+
+#include "../comedidev.h"
+#include <linux/ioport.h>
+
+#define PARPORT_SIZE 3
+
+#define PARPORT_A 0
+#define PARPORT_B 1
+#define PARPORT_C 2
+
+static int parport_attach(comedi_device * dev, comedi_devconfig * it);
+static int parport_detach(comedi_device * dev);
+static comedi_driver driver_parport = {
+ driver_name:"comedi_parport",
+ module:THIS_MODULE,
+ attach:parport_attach,
+ detach:parport_detach,
+};
+
+COMEDI_INITCLEANUP(driver_parport);
+
+typedef struct parport_private_struct {
+ unsigned int a_data;
+ unsigned int c_data;
+ int enable_irq;
+} parport_private;
+#define devpriv ((parport_private *)(dev->private))
+
+static int parport_insn_a(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ if (data[0]) {
+ devpriv->a_data &= ~data[0];
+ devpriv->a_data |= (data[0] & data[1]);
+
+ outb(devpriv->a_data, dev->iobase + PARPORT_A);
+ }
+
+ data[1] = inb(dev->iobase + PARPORT_A);
+
+ return 2;
+}
+
+static int parport_insn_config_a(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ if (data[0]) {
+ s->io_bits = 0xff;
+ devpriv->c_data &= ~(1 << 5);
+ } else {
+ s->io_bits = 0;
+ devpriv->c_data |= (1 << 5);
+ }
+ outb(devpriv->c_data, dev->iobase + PARPORT_C);
+
+ return 1;
+}
+
+static int parport_insn_b(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ if (data[0]) {
+ // should writes be ignored?
+ }
+
+ data[1] = (inb(dev->iobase + PARPORT_B) >> 3);
+
+ return 2;
+}
+
+static int parport_insn_c(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ data[0] &= 0x0f;
+ if (data[0]) {
+ devpriv->c_data &= ~data[0];
+ devpriv->c_data |= (data[0] & data[1]);
+
+ outb(devpriv->c_data, dev->iobase + PARPORT_C);
+ }
+
+ data[1] = devpriv->c_data & 0xf;
+
+ return 2;
+}
+
+static int parport_intr_insn(comedi_device * dev, comedi_subdevice * s,
+ comedi_insn * insn, lsampl_t * data)
+{
+ if (insn->n < 1)
+ return -EINVAL;
+
+ data[1] = 0;
+ return 2;
+}
+
+static int parport_intr_cmdtest(comedi_device * dev, comedi_subdevice * s,
+ comedi_cmd * cmd)
+{
+ int err = 0;
+ int tmp;
+
+ /* step 1 */
+
+ tmp = cmd->start_src;
+ cmd->start_src &= TRIG_NOW;
+ if (!cmd->start_src || tmp != cmd->start_src)
+ err++;
+
+ tmp = cmd->scan_begin_src;
+ cmd->scan_begin_src &= TRIG_EXT;
+ if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
+ err++;
+
+ tmp = cmd->convert_src;
+ cmd->convert_src &= TRIG_FOLLOW;
+ if (!cmd->convert_src || tmp != cmd->convert_src)
+ err++;
+
+ tmp = cmd->scan_end_src;
+ cmd->scan_end_src &= TRIG_COUNT;
+ if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
+ err++;
+
+ tmp = cmd->stop_src;
+ cmd->stop_src &= TRIG_NONE;
+ if (!cmd->stop_src || tmp != cmd->stop_src)
+ err++;
+
+ if (err)
+ return 1;
+
+ /* step 2: ignored */
+
+ if (err)
+ return 2;
+
+ /* step 3: */
+
+ if (cmd->start_arg != 0) {
+ cmd->start_arg = 0;
+ err++;
+ }
+ if (cmd->scan_begin_arg != 0) {
+ cmd->scan_begin_arg = 0;
+ err++;
+ }
+ if (cmd->convert_arg != 0) {
+ cmd->convert_arg = 0;
+ err++;
+ }
+ if (cmd->scan_end_arg != 1) {
+ cmd->scan_end_arg = 1;
+ err++;
+ }
+ if (cmd->stop_arg != 0) {
+ cmd->stop_arg = 0;
+ err++;
+ }
+
+ if (err)
+ return 3;
+
+ /* step 4: ignored */
+
+ if (err)
+ return 4;
+
+ return 0;
+}
+
+static int parport_intr_cmd(comedi_device * dev, comedi_subdevice * s)
+{
+ devpriv->c_data |= 0x10;
+ outb(devpriv->c_data, dev->iobase + PARPORT_C);
+
+ devpriv->enable_irq = 1;
+
+ return 0;
+}
+
+static int parport_intr_cancel(comedi_device * dev, comedi_subdevice * s)
+{
+ printk("parport_intr_cancel()\n");
+
+ devpriv->c_data &= ~0x10;
+ outb(devpriv->c_data, dev->iobase + PARPORT_C);
+
+ devpriv->enable_irq = 0;
+
+ return 0;
+}
+
+static irqreturn_t parport_interrupt(int irq, void *d PT_REGS_ARG)
+{
+ comedi_device *dev = d;
+ comedi_subdevice *s = dev->subdevices + 3;
+
+ if (!devpriv->enable_irq) {
+ printk("comedi_parport: bogus irq, ignored\n");
+ return IRQ_NONE;
+ }
+
+ comedi_buf_put(s->async, 0);
+ s->async->events |= COMEDI_CB_BLOCK | COMEDI_CB_EOS;
+
+ comedi_event(dev, s);
+ return IRQ_HANDLED;
+}
+
+static int parport_attach(comedi_device * dev, comedi_devconfig * it)
+{
+ int ret;
+ unsigned int irq;
+ unsigned long iobase;
+ comedi_subdevice *s;
+
+ iobase = it->options[0];
+ printk("comedi%d: parport: 0x%04lx ", dev->minor, iobase);
+ if (!request_region(iobase, PARPORT_SIZE, "parport (comedi)")) {
+ printk("I/O port conflict\n");
+ return -EIO;
+ }
+ dev->iobase = iobase;
+
+ irq = it->options[1];
+ if (irq) {
+ printk(" irq=%u", irq);
+ ret = comedi_request_irq(irq, parport_interrupt, 0,
+ "comedi_parport", dev);
+ if (ret < 0) {
+ printk(" irq not available\n");
+ return -EINVAL;
+ }
+ dev->irq = irq;
+ }
+ dev->board_name = "parport";
+
+ if ((ret = alloc_subdevices(dev, 4)) < 0)
+ return ret;
+ if ((ret = alloc_private(dev, sizeof(parport_private))) < 0)
+ return ret;
+
+ s = dev->subdevices + 0;
+ s->type = COMEDI_SUBD_DIO;
+ s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
+ s->n_chan = 8;
+ s->maxdata = 1;
+ s->range_table = &range_digital;
+ s->insn_bits = parport_insn_a;
+ s->insn_config = parport_insn_config_a;
+
+ s = dev->subdevices + 1;
+ s->type = COMEDI_SUBD_DI;
+ s->subdev_flags = SDF_READABLE;
+ s->n_chan = 5;
+ s->maxdata = 1;
+ s->range_table = &range_digital;
+ s->insn_bits = parport_insn_b;
+
+ s = dev->subdevices + 2;
+ s->type = COMEDI_SUBD_DO;
+ s->subdev_flags = SDF_WRITABLE;
+ s->n_chan = 4;
+ s->maxdata = 1;
+ s->range_table = &range_digital;
+ s->insn_bits = parport_insn_c;
+
+ s = dev->subdevices + 3;
+ if (irq) {
+ dev->read_subdev = s;
+ s->type = COMEDI_SUBD_DI;
+ s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
+ s->n_chan = 1;
+ s->maxdata = 1;
+ s->range_table = &range_digital;
+ s->insn_bits = parport_intr_insn;
+ s->do_cmdtest = parport_intr_cmdtest;
+ s->do_cmd = parport_intr_cmd;
+ s->cancel = parport_intr_cancel;
+ } else {
+ s->type = COMEDI_SUBD_UNUSED;
+ }
+
+ devpriv->a_data = 0;
+ outb(devpriv->a_data, dev->iobase + PARPORT_A);
+ devpriv->c_data = 0;
+ outb(devpriv->c_data, dev->iobase + PARPORT_C);
+
+ printk("\n");
+ return 1;
+}
+
+static int parport_detach(comedi_device * dev)
+{
+ printk("comedi%d: parport: remove\n", dev->minor);
+
+ if (dev->iobase)
+ release_region(dev->iobase, PARPORT_SIZE);
+
+ if (dev->irq)
+ comedi_free_irq(dev->irq, dev);
+
+ return 0;
+}