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diff --git a/drivers/staging/comedi/drivers/comedi_bond.c b/drivers/staging/comedi/drivers/comedi_bond.c
new file mode 100644
index 000000000..96db0c268
--- /dev/null
+++ b/drivers/staging/comedi/drivers/comedi_bond.c
@@ -0,0 +1,355 @@
+/*
+ * comedi_bond.c
+ * A Comedi driver to 'bond' or merge multiple drivers and devices as one.
+ *
+ * COMEDI - Linux Control and Measurement Device Interface
+ * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
+ * Copyright (C) 2005 Calin A. Culianu <calin@ajvar.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.
+ */
+
+/*
+ * Driver: comedi_bond
+ * Description: A driver to 'bond' (merge) multiple subdevices from multiple
+ * devices together as one.
+ * Devices:
+ * Author: ds
+ * Updated: Mon, 10 Oct 00:18:25 -0500
+ * Status: works
+ *
+ * This driver allows you to 'bond' (merge) multiple comedi subdevices
+ * (coming from possibly difference boards and/or drivers) together.  For
+ * example, if you had a board with 2 different DIO subdevices, and
+ * another with 1 DIO subdevice, you could 'bond' them with this driver
+ * so that they look like one big fat DIO subdevice.  This makes writing
+ * applications slightly easier as you don't have to worry about managing
+ * different subdevices in the application -- you just worry about
+ * indexing one linear array of channel id's.
+ *
+ * Right now only DIO subdevices are supported as that's the personal itch
+ * I am scratching with this driver.  If you want to add support for AI and AO
+ * subdevs, go right on ahead and do so!
+ *
+ * Commands aren't supported -- although it would be cool if they were.
+ *
+ * Configuration Options:
+ *   List of comedi-minors to bond.  All subdevices of the same type
+ *   within each minor will be concatenated together in the order given here.
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include "../comedi.h"
+#include "../comedilib.h"
+#include "../comedidev.h"
+
+struct bonded_device {
+	struct comedi_device *dev;
+	unsigned minor;
+	unsigned subdev;
+	unsigned nchans;
+};
+
+struct comedi_bond_private {
+	char name[256];
+	struct bonded_device **devs;
+	unsigned ndevs;
+	unsigned nchans;
+};
+
+static int bonding_dio_insn_bits(struct comedi_device *dev,
+				 struct comedi_subdevice *s,
+				 struct comedi_insn *insn, unsigned int *data)
+{
+	struct comedi_bond_private *devpriv = dev->private;
+	unsigned int n_left, n_done, base_chan;
+	unsigned int write_mask, data_bits;
+	struct bonded_device **devs;
+
+	write_mask = data[0];
+	data_bits = data[1];
+	base_chan = CR_CHAN(insn->chanspec);
+	/* do a maximum of 32 channels, starting from base_chan. */
+	n_left = devpriv->nchans - base_chan;
+	if (n_left > 32)
+		n_left = 32;
+
+	n_done = 0;
+	devs = devpriv->devs;
+	do {
+		struct bonded_device *bdev = *devs++;
+
+		if (base_chan < bdev->nchans) {
+			/* base channel falls within bonded device */
+			unsigned int b_chans, b_mask, b_write_mask, b_data_bits;
+			int ret;
+
+			/*
+			 * Get num channels to do for bonded device and set
+			 * up mask and data bits for bonded device.
+			 */
+			b_chans = bdev->nchans - base_chan;
+			if (b_chans > n_left)
+				b_chans = n_left;
+			b_mask = (1U << b_chans) - 1;
+			b_write_mask = (write_mask >> n_done) & b_mask;
+			b_data_bits = (data_bits >> n_done) & b_mask;
+			/* Read/Write the new digital lines. */
+			ret = comedi_dio_bitfield2(bdev->dev, bdev->subdev,
+						   b_write_mask, &b_data_bits,
+						   base_chan);
+			if (ret < 0)
+				return ret;
+			/* Place read bits into data[1]. */
+			data[1] &= ~(b_mask << n_done);
+			data[1] |= (b_data_bits & b_mask) << n_done;
+			/*
+			 * Set up for following bonded device (if still have
+			 * channels to read/write).
+			 */
+			base_chan = 0;
+			n_done += b_chans;
+			n_left -= b_chans;
+		} else {
+			/* Skip bonded devices before base channel. */
+			base_chan -= bdev->nchans;
+		}
+	} while (n_left);
+
+	return insn->n;
+}
+
+static int bonding_dio_insn_config(struct comedi_device *dev,
+				   struct comedi_subdevice *s,
+				   struct comedi_insn *insn, unsigned int *data)
+{
+	struct comedi_bond_private *devpriv = dev->private;
+	unsigned int chan = CR_CHAN(insn->chanspec);
+	int ret;
+	struct bonded_device *bdev;
+	struct bonded_device **devs;
+
+	/*
+	 * Locate bonded subdevice and adjust channel.
+	 */
+	devs = devpriv->devs;
+	for (bdev = *devs++; chan >= bdev->nchans; bdev = *devs++)
+		chan -= bdev->nchans;
+
+	/*
+	 * The input or output configuration of each digital line is
+	 * configured by a special insn_config instruction.  chanspec
+	 * contains the channel to be changed, and data[0] contains the
+	 * configuration instruction INSN_CONFIG_DIO_OUTPUT,
+	 * INSN_CONFIG_DIO_INPUT or INSN_CONFIG_DIO_QUERY.
+	 *
+	 * Note that INSN_CONFIG_DIO_OUTPUT == COMEDI_OUTPUT,
+	 * and INSN_CONFIG_DIO_INPUT == COMEDI_INPUT.  This is deliberate ;)
+	 */
+	switch (data[0]) {
+	case INSN_CONFIG_DIO_OUTPUT:
+	case INSN_CONFIG_DIO_INPUT:
+		ret = comedi_dio_config(bdev->dev, bdev->subdev, chan, data[0]);
+		break;
+	case INSN_CONFIG_DIO_QUERY:
+		ret = comedi_dio_get_config(bdev->dev, bdev->subdev, chan,
+					    &data[1]);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	if (ret >= 0)
+		ret = insn->n;
+	return ret;
+}
+
+static int do_dev_config(struct comedi_device *dev, struct comedi_devconfig *it)
+{
+	struct comedi_bond_private *devpriv = dev->private;
+	DECLARE_BITMAP(devs_opened, COMEDI_NUM_BOARD_MINORS);
+	int i;
+
+	memset(&devs_opened, 0, sizeof(devs_opened));
+	devpriv->name[0] = 0;
+	/*
+	 * Loop through all comedi devices specified on the command-line,
+	 * building our device list.
+	 */
+	for (i = 0; i < COMEDI_NDEVCONFOPTS && (!i || it->options[i]); ++i) {
+		char file[sizeof("/dev/comediXXXXXX")];
+		int minor = it->options[i];
+		struct comedi_device *d;
+		int sdev = -1, nchans;
+		struct bonded_device *bdev;
+		struct bonded_device **devs;
+
+		if (minor < 0 || minor >= COMEDI_NUM_BOARD_MINORS) {
+			dev_err(dev->class_dev,
+				"Minor %d is invalid!\n", minor);
+			return -EINVAL;
+		}
+		if (minor == dev->minor) {
+			dev_err(dev->class_dev,
+				"Cannot bond this driver to itself!\n");
+			return -EINVAL;
+		}
+		if (test_and_set_bit(minor, devs_opened)) {
+			dev_err(dev->class_dev,
+				"Minor %d specified more than once!\n", minor);
+			return -EINVAL;
+		}
+
+		snprintf(file, sizeof(file), "/dev/comedi%d", minor);
+		file[sizeof(file) - 1] = 0;
+
+		d = comedi_open(file);
+
+		if (!d) {
+			dev_err(dev->class_dev,
+				"Minor %u could not be opened\n", minor);
+			return -ENODEV;
+		}
+
+		/* Do DIO, as that's all we support now.. */
+		while ((sdev = comedi_find_subdevice_by_type(d, COMEDI_SUBD_DIO,
+							     sdev + 1)) > -1) {
+			nchans = comedi_get_n_channels(d, sdev);
+			if (nchans <= 0) {
+				dev_err(dev->class_dev,
+					"comedi_get_n_channels() returned %d on minor %u subdev %d!\n",
+					nchans, minor, sdev);
+				return -EINVAL;
+			}
+			bdev = kmalloc(sizeof(*bdev), GFP_KERNEL);
+			if (!bdev)
+				return -ENOMEM;
+
+			bdev->dev = d;
+			bdev->minor = minor;
+			bdev->subdev = sdev;
+			bdev->nchans = nchans;
+			devpriv->nchans += nchans;
+
+			/*
+			 * Now put bdev pointer at end of devpriv->devs array
+			 * list..
+			 */
+
+			/* ergh.. ugly.. we need to realloc :(  */
+			devs = krealloc(devpriv->devs,
+					(devpriv->ndevs + 1) * sizeof(*devs),
+					GFP_KERNEL);
+			if (!devs) {
+				dev_err(dev->class_dev,
+					"Could not allocate memory. Out of memory?\n");
+				kfree(bdev);
+				return -ENOMEM;
+			}
+			devpriv->devs = devs;
+			devpriv->devs[devpriv->ndevs++] = bdev;
+			{
+				/* Append dev:subdev to devpriv->name */
+				char buf[20];
+
+				snprintf(buf, sizeof(buf), "%u:%u ",
+					 bdev->minor, bdev->subdev);
+				strlcat(devpriv->name, buf,
+					sizeof(devpriv->name));
+			}
+		}
+	}
+
+	if (!devpriv->nchans) {
+		dev_err(dev->class_dev, "No channels found!\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bonding_attach(struct comedi_device *dev,
+			  struct comedi_devconfig *it)
+{
+	struct comedi_bond_private *devpriv;
+	struct comedi_subdevice *s;
+	int ret;
+
+	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
+	if (!devpriv)
+		return -ENOMEM;
+
+	/*
+	 * Setup our bonding from config params.. sets up our private struct..
+	 */
+	ret = do_dev_config(dev, it);
+	if (ret)
+		return ret;
+
+	dev->board_name = devpriv->name;
+
+	ret = comedi_alloc_subdevices(dev, 1);
+	if (ret)
+		return ret;
+
+	s = &dev->subdevices[0];
+	s->type = COMEDI_SUBD_DIO;
+	s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
+	s->n_chan = devpriv->nchans;
+	s->maxdata = 1;
+	s->range_table = &range_digital;
+	s->insn_bits = bonding_dio_insn_bits;
+	s->insn_config = bonding_dio_insn_config;
+
+	dev_info(dev->class_dev,
+		 "%s: %s attached, %u channels from %u devices\n",
+		 dev->driver->driver_name, dev->board_name,
+		 devpriv->nchans, devpriv->ndevs);
+
+	return 0;
+}
+
+static void bonding_detach(struct comedi_device *dev)
+{
+	struct comedi_bond_private *devpriv = dev->private;
+
+	if (devpriv && devpriv->devs) {
+		DECLARE_BITMAP(devs_closed, COMEDI_NUM_BOARD_MINORS);
+
+		memset(&devs_closed, 0, sizeof(devs_closed));
+		while (devpriv->ndevs--) {
+			struct bonded_device *bdev;
+
+			bdev = devpriv->devs[devpriv->ndevs];
+			if (!bdev)
+				continue;
+			if (!test_and_set_bit(bdev->minor, devs_closed))
+				comedi_close(bdev->dev);
+			kfree(bdev);
+		}
+		kfree(devpriv->devs);
+		devpriv->devs = NULL;
+	}
+}
+
+static struct comedi_driver bonding_driver = {
+	.driver_name	= "comedi_bond",
+	.module		= THIS_MODULE,
+	.attach		= bonding_attach,
+	.detach		= bonding_detach,
+};
+module_comedi_driver(bonding_driver);
+
+MODULE_AUTHOR("Calin A. Culianu");
+MODULE_DESCRIPTION("comedi_bond: A driver for COMEDI to bond multiple COMEDI devices together as one.");
+MODULE_LICENSE("GPL");