Staging: comedi: add cb_pcidio driver

Driver for PCI-DIO24H & PCI-DIO48H of ComputerBoards (currently
MeasurementComputing)

From: Yoshiya Matsuzaka <matsuzay@mail.cc.tohoku.ac.jp>
Cc: David Schleef <ds@schleef.org>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/drivers/cb_pcidio.c

+/*
+    comedi/drivers/cb_pcidio.c
+    A Comedi driver for PCI-DIO24H & PCI-DIO48H of ComputerBoards (currently MeasurementComputing)
+
+    COMEDI - Linux Control and Measurement Device Interface
+    Copyright (C) 2000 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: cb_pcidio
+Description: ComputerBoards' DIO boards with PCI interface
+Devices: [Measurement Computing] PCI-DIO24 (cb_pcidio), PCI-DIO24H, PCI-DIO48H
+Author: Yoshiya Matsuzaka
+Updated: Mon, 29 Oct 2007 15:40:47 +0000
+Status: experimental
+
+This driver has been modified from skel.c of comedi-0.7.70.
+
+Configuration Options:
+  [0] - PCI bus of device (optional)
+  [1] - PCI slot of device (optional)
+  If bus/slot is not specified, the first available PCI device will
+  be used.
+
+Passing a zero for an option is the same as leaving it unspecified.
+*/
+
+/*------------------------------ HEADER FILES ---------------------------------*/
+#include "../comedidev.h"
+#include "comedi_pci.h"
+#include "8255.h"
+
+/*-------------------------- MACROS and DATATYPES -----------------------------*/
+#define PCI_VENDOR_ID_CB	0x1307
+
+/*
+ * Board descriptions for two imaginary boards.  Describing the
+ * boards in this way is optional, and completely driver-dependent.
+ * Some drivers use arrays such as this, other do not.
+ */
+typedef struct pcidio_board_struct {
+	const char *name;	// anme of the board
+	int n_8255;		// number of 8255 chips on board
+
+	// indices of base address regions
+	int pcicontroler_badrindex;
+	int dioregs_badrindex;
+} pcidio_board;
+
+static const pcidio_board pcidio_boards[] = {
+	{
+	      name:	"pci-dio24",
+	      n_8255:	1,
+	      pcicontroler_badrindex:1,
+	      dioregs_badrindex:2,
+		},
+	{
+	      name:	"pci-dio24h",
+	      n_8255:	1,
+	      pcicontroler_badrindex:1,
+	      dioregs_badrindex:2,
+		},
+	{
+	      name:	"pci-dio48h",
+	      n_8255:	2,
+	      pcicontroler_badrindex:0,
+	      dioregs_badrindex:1,
+		},
+};
+
+/* This is used by modprobe to translate PCI IDs to drivers.  Should
+ * only be used for PCI and ISA-PnP devices */
+/* Please add your PCI vendor ID to comedidev.h, and it will be forwarded
+ * upstream. */
+static DEFINE_PCI_DEVICE_TABLE(pcidio_pci_table) = {
+	{PCI_VENDOR_ID_CB, 0x0028, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+	{PCI_VENDOR_ID_CB, 0x0014, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+	{PCI_VENDOR_ID_CB, 0x000b, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+	{0}
+};
+
+MODULE_DEVICE_TABLE(pci, pcidio_pci_table);
+
+/*
+ * Useful for shorthand access to the particular board structure
+ */
+#define thisboard ((const pcidio_board *)dev->board_ptr)
+
+/* this structure is for data unique to this hardware driver.  If
+   several hardware drivers keep similar information in this structure,
+   feel free to suggest moving the variable to the comedi_device struct.  */
+typedef struct {
+	int data;		// curently unused
+
+	/* would be useful for a PCI device */
+	struct pci_dev *pci_dev;
+
+	/* used for DO readback, curently unused */
+	lsampl_t do_readback[4];	/* up to 4 lsampl_t suffice to hold 96 bits for PCI-DIO96 */
+
+	unsigned long dio_reg_base;	// address of port A of the first 8255 chip on board
+} pcidio_private;
+
+/*
+ * most drivers define the following macro to make it easy to
+ * access the private structure.
+ */
+#define devpriv ((pcidio_private *)dev->private)
+
+/*
+ * The comedi_driver structure tells the Comedi core module
+ * which functions to call to configure/deconfigure (attach/detach)
+ * the board, and also about the kernel module that contains
+ * the device code.
+ */
+static int pcidio_attach(comedi_device * dev, comedi_devconfig * it);
+static int pcidio_detach(comedi_device * dev);
+static comedi_driver driver_cb_pcidio = {
+      driver_name:"cb_pcidio",
+      module:THIS_MODULE,
+      attach:pcidio_attach,
+      detach:pcidio_detach,
+/* It is not necessary to implement the following members if you are
+ * writing a driver for a ISA PnP or PCI card */
+	/* Most drivers will support multiple types of boards by
+	 * having an array of board structures.  These were defined
+	 * in pcidio_boards[] above.  Note that the element 'name'
+	 * was first in the structure -- Comedi uses this fact to
+	 * extract the name of the board without knowing any details
+	 * about the structure except for its length.
+	 * When a device is attached (by comedi_config), the name
+	 * of the device is given to Comedi, and Comedi tries to
+	 * match it by going through the list of board names.  If
+	 * there is a match, the address of the pointer is put
+	 * into dev->board_ptr and driver->attach() is called.
+	 *
+	 * Note that these are not necessary if you can determine
+	 * the type of board in software.  ISA PnP, PCI, and PCMCIA
+	 * devices are such boards.
+	 */
+// The following fields should NOT be initialized if you are dealing with PCI devices
+//      board_name:     pcidio_boards,
+//      offset:         sizeof(pcidio_board),
+//      num_names:      sizeof(pcidio_boards) / sizeof(pcidio_board),
+};
+
+/*------------------------------- FUNCTIONS -----------------------------------*/
+
+/*
+ * Attach is called by the Comedi core to configure the driver
+ * for a particular board.  If you specified a board_name array
+ * in the driver structure, dev->board_ptr contains that
+ * address.
+ */
+static int pcidio_attach(comedi_device * dev, comedi_devconfig * it)
+{
+	struct pci_dev *pcidev = NULL;
+	int index;
+	int i;
+
+	printk("comedi%d: cb_pcidio: \n", dev->minor);
+
+/*
+ * Allocate the private structure area.  alloc_private() is a
+ * convenient macro defined in comedidev.h.
+ */
+	if (alloc_private(dev, sizeof(pcidio_private)) < 0)
+		return -ENOMEM;
+/*
+ * If you can probe the device to determine what device in a series
+ * it is, this is the place to do it.  Otherwise, dev->board_ptr
+ * should already be initialized.
+ */
+/*
+ * Probe the device to determine what device in the series it is.
+ */
+
+	for (pcidev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
+		pcidev != NULL;
+		pcidev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, pcidev)) {
+		// is it not a computer boards card?
+		if (pcidev->vendor != PCI_VENDOR_ID_CB)
+			continue;
+		// loop through cards supported by this driver
+		for (index = 0;
+			index < sizeof pcidio_boards / sizeof(pcidio_board);
+			index++) {
+			if (pcidio_pci_table[index].device != pcidev->device)
+				continue;
+
+			// was a particular bus/slot requested?
+			if (it->options[0] || it->options[1]) {
+				// are we on the wrong bus/slot?
+				if (pcidev->bus->number != it->options[0] ||
+					PCI_SLOT(pcidev->devfn) !=
+					it->options[1]) {
+					continue;
+				}
+			}
+			dev->board_ptr = pcidio_boards + index;
+			goto found;
+		}
+	}
+
+	printk("No supported ComputerBoards/MeasurementComputing card found on "
+		"requested position\n");
+	return -EIO;
+
+      found:
+
+/*
+ * Initialize dev->board_name.  Note that we can use the "thisboard"
+ * macro now, since we just initialized it in the last line.
+ */
+	dev->board_name = thisboard->name;
+
+	devpriv->pci_dev = pcidev;
+	printk("Found %s on bus %i, slot %i\n", thisboard->name,
+		devpriv->pci_dev->bus->number,
+		PCI_SLOT(devpriv->pci_dev->devfn));
+	if (comedi_pci_enable(pcidev, thisboard->name)) {
+		printk("cb_pcidio: failed to enable PCI device and request regions\n");
+		return -EIO;
+	}
+	devpriv->dio_reg_base
+		=
+		pci_resource_start(devpriv->pci_dev,
+		pcidio_boards[index].dioregs_badrindex);
+
+/*
+ * Allocate the subdevice structures.  alloc_subdevice() is a
+ * convenient macro defined in comedidev.h.
+ */
+	if (alloc_subdevices(dev, thisboard->n_8255) < 0)
+		return -ENOMEM;
+
+	for (i = 0; i < thisboard->n_8255; i++) {
+		subdev_8255_init(dev, dev->subdevices + i,
+			NULL, devpriv->dio_reg_base + i * 4);
+		printk(" subdev %d: base = 0x%lx\n", i,
+			devpriv->dio_reg_base + i * 4);
+	}
+
+	printk("attached\n");
+	return 1;
+}
+
+/*
+ * _detach is called to deconfigure a device.  It should deallocate
+ * resources.
+ * This function is also called when _attach() fails, so it should be
+ * careful not to release resources that were not necessarily
+ * allocated by _attach().  dev->private and dev->subdevices are
+ * deallocated automatically by the core.
+ */
+static int pcidio_detach(comedi_device * dev)
+{
+	printk("comedi%d: cb_pcidio: remove\n", dev->minor);
+	if (devpriv) {
+		if (devpriv->pci_dev) {
+			if (devpriv->dio_reg_base) {
+				comedi_pci_disable(devpriv->pci_dev);
+			}
+			pci_dev_put(devpriv->pci_dev);
+		}
+	}
+	if (dev->subdevices) {
+		int i;
+		for (i = 0; i < thisboard->n_8255; i++) {
+			subdev_8255_cleanup(dev, dev->subdevices + i);
+		}
+	}
+	return 0;
+}
+
+/*
+ * A convenient macro that defines init_module() and cleanup_module(),
+ * as necessary.
+ */
+COMEDI_PCI_INITCLEANUP(driver_cb_pcidio, pcidio_pci_table);