--- /dev/null
+/*
+ comedi/drivers/8255.c
+ Driver for 8255
+
+ COMEDI - Linux Control and Measurement Device Interface
+ Copyright (C) 1998 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: 8255
+Description: generic 8255 support
+Devices: [standard] 8255 (8255)
+Author: ds
+Status: works
+Updated: Fri, 7 Jun 2002 12:56:45 -0700
+
+The classic in digital I/O. The 8255 appears in Comedi as a single
+digital I/O subdevice with 24 channels. The channel 0 corresponds
+to the 8255's port A, bit 0; channel 23 corresponds to port C, bit
+7. Direction configuration is done in blocks, with channels 0-7,
+8-15, 16-19, and 20-23 making up the 4 blocks. The only 8255 mode
+supported is mode 0.
+
+You should enable compilation this driver if you plan to use a board
+that has an 8255 chip. For multifunction boards, the main driver will
+configure the 8255 subdevice automatically.
+
+This driver also works independently with ISA and PCI cards that
+directly map the 8255 registers to I/O ports, including cards with
+multiple 8255 chips. To configure the driver for such a card, the
+option list should be a list of the I/O port bases for each of the
+8255 chips. For example,
+
+ comedi_config /dev/comedi0 8255 0x200,0x204,0x208,0x20c
+
+Note that most PCI 8255 boards do NOT work with this driver, and
+need a separate driver as a wrapper. For those that do work, the
+I/O port base address can be found in the output of 'lspci -v'.
+
+*/
+
+/*
+ This file contains an exported subdevice for driving an 8255.
+
+ To use this subdevice as part of another driver, you need to
+ set up the subdevice in the attach function of the driver by
+ calling:
+
+ subdev_8255_init(device, subdevice, callback_function, arg)
+
+ device and subdevice are pointers to the device and subdevice
+ structures. callback_function will be called to provide the
+ low-level input/output to the device, i.e., actual register
+ access. callback_function will be called with the value of arg
+ as the last parameter. If the 8255 device is mapped as 4
+ consecutive I/O ports, you can use NULL for callback_function
+ and the I/O port base for arg, and an internal function will
+ handle the register access.
+
+ In addition, if the main driver handles interrupts, you can
+ enable commands on the subdevice by calling subdev_8255_init_irq()
+ instead. Then, when you get an interrupt that is likely to be
+ from the 8255, you should call subdev_8255_interrupt(), which
+ will copy the latched value to a Comedi buffer.
+ */
+
+#include "../comedidev.h"
+
+#include <linux/ioport.h>
+
+#define _8255_SIZE 4
+
+#define _8255_DATA 0
+#define _8255_CR 3
+
+#define CR_C_LO_IO 0x01
+#define CR_B_IO 0x02
+#define CR_B_MODE 0x04
+#define CR_C_HI_IO 0x08
+#define CR_A_IO 0x10
+#define CR_A_MODE(a) ((a)<<5)
+#define CR_CW 0x80
+
+struct subdev_8255_struct {
+ unsigned long cb_arg;
+ int (*cb_func) (int, int, int, unsigned long);
+ int have_irq;
+};
+
+#define CALLBACK_ARG (((struct subdev_8255_struct *)s->private)->cb_arg)
+#define CALLBACK_FUNC (((struct subdev_8255_struct *)s->private)->cb_func)
+#define subdevpriv ((struct subdev_8255_struct *)s->private)
+
+static int dev_8255_attach(struct comedi_device *dev, struct comedi_devconfig * it);
+static int dev_8255_detach(struct comedi_device *dev);
+static struct comedi_driver driver_8255 = {
+ driver_name:"8255",
+ module:THIS_MODULE,
+ attach:dev_8255_attach,
+ detach:dev_8255_detach,
+};
+
+COMEDI_INITCLEANUP(driver_8255);
+
+static void do_config(struct comedi_device *dev, struct comedi_subdevice * s);
+
+void subdev_8255_interrupt(struct comedi_device *dev, struct comedi_subdevice * s)
+{
+ short d;
+
+ d = CALLBACK_FUNC(0, _8255_DATA, 0, CALLBACK_ARG);
+ d |= (CALLBACK_FUNC(0, _8255_DATA + 1, 0, CALLBACK_ARG) << 8);
+
+ comedi_buf_put(s->async, d);
+ s->async->events |= COMEDI_CB_EOS;
+
+ comedi_event(dev, s);
+}
+
+static int subdev_8255_cb(int dir, int port, int data, unsigned long arg)
+{
+ unsigned long iobase = arg;
+
+ if (dir) {
+ outb(data, iobase + port);
+ return 0;
+ } else {
+ return inb(iobase + port);
+ }
+}
+
+static int subdev_8255_insn(struct comedi_device *dev, struct comedi_subdevice * s,
+ struct comedi_insn * insn, unsigned int * data)
+{
+ if (data[0]) {
+ s->state &= ~data[0];
+ s->state |= (data[0] & data[1]);
+
+ if (data[0] & 0xff)
+ CALLBACK_FUNC(1, _8255_DATA, s->state & 0xff,
+ CALLBACK_ARG);
+ if (data[0] & 0xff00)
+ CALLBACK_FUNC(1, _8255_DATA + 1, (s->state >> 8) & 0xff,
+ CALLBACK_ARG);
+ if (data[0] & 0xff0000)
+ CALLBACK_FUNC(1, _8255_DATA + 2,
+ (s->state >> 16) & 0xff, CALLBACK_ARG);
+ }
+
+ data[1] = CALLBACK_FUNC(0, _8255_DATA, 0, CALLBACK_ARG);
+ data[1] |= (CALLBACK_FUNC(0, _8255_DATA + 1, 0, CALLBACK_ARG) << 8);
+ data[1] |= (CALLBACK_FUNC(0, _8255_DATA + 2, 0, CALLBACK_ARG) << 16);
+
+ return 2;
+}
+
+static int subdev_8255_insn_config(struct comedi_device *dev, struct comedi_subdevice * s,
+ struct comedi_insn * insn, unsigned int * data)
+{
+ unsigned int mask;
+ unsigned int bits;
+
+ mask = 1 << CR_CHAN(insn->chanspec);
+ if (mask & 0x0000ff) {
+ bits = 0x0000ff;
+ } else if (mask & 0x00ff00) {
+ bits = 0x00ff00;
+ } else if (mask & 0x0f0000) {
+ bits = 0x0f0000;
+ } else {
+ bits = 0xf00000;
+ }
+
+ switch (data[0]) {
+ case INSN_CONFIG_DIO_INPUT:
+ s->io_bits &= ~bits;
+ break;
+ case INSN_CONFIG_DIO_OUTPUT:
+ s->io_bits |= bits;
+ break;
+ case INSN_CONFIG_DIO_QUERY:
+ data[1] = (s->io_bits & bits) ? COMEDI_OUTPUT : COMEDI_INPUT;
+ return insn->n;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ do_config(dev, s);
+
+ return 1;
+}
+
+static void do_config(struct comedi_device *dev, struct comedi_subdevice * s)
+{
+ int config;
+
+ config = CR_CW;
+ /* 1 in io_bits indicates output, 1 in config indicates input */
+ if (!(s->io_bits & 0x0000ff))
+ config |= CR_A_IO;
+ if (!(s->io_bits & 0x00ff00))
+ config |= CR_B_IO;
+ if (!(s->io_bits & 0x0f0000))
+ config |= CR_C_LO_IO;
+ if (!(s->io_bits & 0xf00000))
+ config |= CR_C_HI_IO;
+ CALLBACK_FUNC(1, _8255_CR, config, CALLBACK_ARG);
+}
+
+static int subdev_8255_cmdtest(struct comedi_device *dev, struct comedi_subdevice * s,
+ struct comedi_cmd * cmd)
+{
+ int err = 0;
+ unsigned 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 */
+
+ 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 */
+
+ if (err)
+ return 4;
+
+ return 0;
+}
+
+static int subdev_8255_cmd(struct comedi_device *dev, struct comedi_subdevice * s)
+{
+ /* FIXME */
+
+ return 0;
+}
+
+static int subdev_8255_cancel(struct comedi_device *dev, struct comedi_subdevice * s)
+{
+ /* FIXME */
+
+ return 0;
+}
+
+int subdev_8255_init(struct comedi_device *dev, struct comedi_subdevice * s, int (*cb) (int,
+ int, int, unsigned long), unsigned long arg)
+{
+ s->type = COMEDI_SUBD_DIO;
+ s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
+ s->n_chan = 24;
+ s->range_table = &range_digital;
+ s->maxdata = 1;
+
+ s->private = kmalloc(sizeof(struct subdev_8255_struct), GFP_KERNEL);
+ if (!s->private)
+ return -ENOMEM;
+
+ CALLBACK_ARG = arg;
+ if (cb == NULL) {
+ CALLBACK_FUNC = subdev_8255_cb;
+ } else {
+ CALLBACK_FUNC = cb;
+ }
+ s->insn_bits = subdev_8255_insn;
+ s->insn_config = subdev_8255_insn_config;
+
+ s->state = 0;
+ s->io_bits = 0;
+ do_config(dev, s);
+
+ return 0;
+}
+
+int subdev_8255_init_irq(struct comedi_device *dev, struct comedi_subdevice * s,
+ int (*cb) (int, int, int, unsigned long), unsigned long arg)
+{
+ int ret;
+
+ ret = subdev_8255_init(dev, s, cb, arg);
+ if (ret < 0)
+ return ret;
+
+ s->do_cmdtest = subdev_8255_cmdtest;
+ s->do_cmd = subdev_8255_cmd;
+ s->cancel = subdev_8255_cancel;
+
+ subdevpriv->have_irq = 1;
+
+ return 0;
+}
+
+void subdev_8255_cleanup(struct comedi_device *dev, struct comedi_subdevice * s)
+{
+ if (s->private) {
+ if (subdevpriv->have_irq) {
+ }
+
+ kfree(s->private);
+ }
+}
+
+/*
+
+ Start of the 8255 standalone device
+
+ */
+
+static int dev_8255_attach(struct comedi_device *dev, struct comedi_devconfig * it)
+{
+ int ret;
+ unsigned long iobase;
+ int i;
+
+ printk("comedi%d: 8255:", dev->minor);
+
+ dev->board_name = "8255";
+
+ for (i = 0; i < COMEDI_NDEVCONFOPTS; i++) {
+ iobase = it->options[i];
+ if (!iobase)
+ break;
+ }
+ if (i == 0) {
+ printk(" no devices specified\n");
+ return -EINVAL;
+ }
+
+ if ((ret = alloc_subdevices(dev, i)) < 0)
+ return ret;
+
+ for (i = 0; i < dev->n_subdevices; i++) {
+ iobase = it->options[i];
+
+ printk(" 0x%04lx", iobase);
+ if (!request_region(iobase, _8255_SIZE, "8255")) {
+ printk(" (I/O port conflict)");
+
+ dev->subdevices[i].type = COMEDI_SUBD_UNUSED;
+ } else {
+ subdev_8255_init(dev, dev->subdevices + i, NULL,
+ iobase);
+ }
+ }
+
+ printk("\n");
+
+ return 0;
+}
+
+static int dev_8255_detach(struct comedi_device *dev)
+{
+ int i;
+ unsigned long iobase;
+ struct comedi_subdevice *s;
+
+ printk("comedi%d: 8255: remove\n", dev->minor);
+
+ for (i = 0; i < dev->n_subdevices; i++) {
+ s = dev->subdevices + i;
+ if (s->type != COMEDI_SUBD_UNUSED) {
+ iobase = CALLBACK_ARG;
+ release_region(iobase, _8255_SIZE);
+ }
+ subdev_8255_cleanup(dev, s);
+ }
+
+ return 0;
+}
+
+EXPORT_SYMBOL(subdev_8255_init);
+EXPORT_SYMBOL(subdev_8255_init_irq);
+EXPORT_SYMBOL(subdev_8255_cleanup);
+EXPORT_SYMBOL(subdev_8255_interrupt);
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