Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1573 insertions, 0 deletions

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
new file mode 100644
index 000000000000..f0534ee06490
--- /dev/null
+++ b/drivers/usb/core/usb.c
@@ -0,0 +1,1573 @@
+/*
+ * drivers/usb/usb.c
+ *
+ * (C) Copyright Linus Torvalds 1999
+ * (C) Copyright Johannes Erdfelt 1999-2001
+ * (C) Copyright Andreas Gal 1999
+ * (C) Copyright Gregory P. Smith 1999
+ * (C) Copyright Deti Fliegl 1999 (new USB architecture)
+ * (C) Copyright Randy Dunlap 2000
+ * (C) Copyright David Brownell 2000-2004
+ * (C) Copyright Yggdrasil Computing, Inc. 2000
+ *     (usb_device_id matching changes by Adam J. Richter)
+ * (C) Copyright Greg Kroah-Hartman 2002-2003
+ *
+ * NOTE! This is not actually a driver at all, rather this is
+ * just a collection of helper routines that implement the
+ * generic USB things that the real drivers can use..
+ *
+ * Think of this as a "USB library" rather than anything else.
+ * It should be considered a slave, with no callbacks. Callbacks
+ * are evil.
+ */
+
+#include <linux/config.h>
+
+#ifdef CONFIG_USB_DEBUG
+	#define DEBUG
+#else
+	#undef DEBUG
+#endif
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>  /* for in_interrupt() */
+#include <linux/kmod.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/smp_lock.h>
+#include <linux/rwsem.h>
+#include <linux/usb.h>
+
+#include <asm/io.h>
+#include <asm/scatterlist.h>
+#include <linux/mm.h>
+#include <linux/dma-mapping.h>
+
+#include "hcd.h"
+#include "usb.h"
+
+extern int  usb_hub_init(void);
+extern void usb_hub_cleanup(void);
+extern int usb_major_init(void);
+extern void usb_major_cleanup(void);
+extern int usb_host_init(void);
+extern void usb_host_cleanup(void);
+
+
+const char *usbcore_name = "usbcore";
+
+static int nousb;	/* Disable USB when built into kernel image */
+			/* Not honored on modular build */
+
+static DECLARE_RWSEM(usb_all_devices_rwsem);
+
+
+static int generic_probe (struct device *dev)
+{
+	return 0;
+}
+static int generic_remove (struct device *dev)
+{
+	return 0;
+}
+
+static struct device_driver usb_generic_driver = {
+	.owner = THIS_MODULE,
+	.name =	"usb",
+	.bus = &usb_bus_type,
+	.probe = generic_probe,
+	.remove = generic_remove,
+};
+
+static int usb_generic_driver_data;
+
+/* called from driver core with usb_bus_type.subsys writelock */
+static int usb_probe_interface(struct device *dev)
+{
+	struct usb_interface * intf = to_usb_interface(dev);
+	struct usb_driver * driver = to_usb_driver(dev->driver);
+	const struct usb_device_id *id;
+	int error = -ENODEV;
+
+	dev_dbg(dev, "%s\n", __FUNCTION__);
+
+	if (!driver->probe)
+		return error;
+	/* FIXME we'd much prefer to just resume it ... */
+	if (interface_to_usbdev(intf)->state == USB_STATE_SUSPENDED)
+		return -EHOSTUNREACH;
+
+	id = usb_match_id (intf, driver->id_table);
+	if (id) {
+		dev_dbg (dev, "%s - got id\n", __FUNCTION__);
+		intf->condition = USB_INTERFACE_BINDING;
+		error = driver->probe (intf, id);
+		intf->condition = error ? USB_INTERFACE_UNBOUND :
+				USB_INTERFACE_BOUND;
+	}
+
+	return error;
+}
+
+/* called from driver core with usb_bus_type.subsys writelock */
+static int usb_unbind_interface(struct device *dev)
+{
+	struct usb_interface *intf = to_usb_interface(dev);
+	struct usb_driver *driver = to_usb_driver(intf->dev.driver);
+
+	intf->condition = USB_INTERFACE_UNBINDING;
+
+	/* release all urbs for this interface */
+	usb_disable_interface(interface_to_usbdev(intf), intf);
+
+	if (driver && driver->disconnect)
+		driver->disconnect(intf);
+
+	/* reset other interface state */
+	usb_set_interface(interface_to_usbdev(intf),
+			intf->altsetting[0].desc.bInterfaceNumber,
+			0);
+	usb_set_intfdata(intf, NULL);
+	intf->condition = USB_INTERFACE_UNBOUND;
+
+	return 0;
+}
+
+/**
+ * usb_register - register a USB driver
+ * @new_driver: USB operations for the driver
+ *
+ * Registers a USB driver with the USB core.  The list of unattached
+ * interfaces will be rescanned whenever a new driver is added, allowing
+ * the new driver to attach to any recognized devices.
+ * Returns a negative error code on failure and 0 on success.
+ * 
+ * NOTE: if you want your driver to use the USB major number, you must call
+ * usb_register_dev() to enable that functionality.  This function no longer
+ * takes care of that.
+ */
+int usb_register(struct usb_driver *new_driver)
+{
+	int retval = 0;
+
+	if (nousb)
+		return -ENODEV;
+
+	new_driver->driver.name = (char *)new_driver->name;
+	new_driver->driver.bus = &usb_bus_type;
+	new_driver->driver.probe = usb_probe_interface;
+	new_driver->driver.remove = usb_unbind_interface;
+	new_driver->driver.owner = new_driver->owner;
+
+	usb_lock_all_devices();
+	retval = driver_register(&new_driver->driver);
+	usb_unlock_all_devices();
+
+	if (!retval) {
+		pr_info("%s: registered new driver %s\n",
+			usbcore_name, new_driver->name);
+		usbfs_update_special();
+	} else {
+		printk(KERN_ERR "%s: error %d registering driver %s\n",
+			usbcore_name, retval, new_driver->name);
+	}
+
+	return retval;
+}
+
+/**
+ * usb_deregister - unregister a USB driver
+ * @driver: USB operations of the driver to unregister
+ * Context: must be able to sleep
+ *
+ * Unlinks the specified driver from the internal USB driver list.
+ * 
+ * NOTE: If you called usb_register_dev(), you still need to call
+ * usb_deregister_dev() to clean up your driver's allocated minor numbers,
+ * this * call will no longer do it for you.
+ */
+void usb_deregister(struct usb_driver *driver)
+{
+	pr_info("%s: deregistering driver %s\n", usbcore_name, driver->name);
+
+	usb_lock_all_devices();
+	driver_unregister (&driver->driver);
+	usb_unlock_all_devices();
+
+	usbfs_update_special();
+}
+
+/**
+ * usb_ifnum_to_if - get the interface object with a given interface number
+ * @dev: the device whose current configuration is considered
+ * @ifnum: the desired interface
+ *
+ * This walks the device descriptor for the currently active configuration
+ * and returns a pointer to the interface with that particular interface
+ * number, or null.
+ *
+ * Note that configuration descriptors are not required to assign interface
+ * numbers sequentially, so that it would be incorrect to assume that
+ * the first interface in that descriptor corresponds to interface zero.
+ * This routine helps device drivers avoid such mistakes.
+ * However, you should make sure that you do the right thing with any
+ * alternate settings available for this interfaces.
+ *
+ * Don't call this function unless you are bound to one of the interfaces
+ * on this device or you have locked the device!
+ */
+struct usb_interface *usb_ifnum_to_if(struct usb_device *dev, unsigned ifnum)
+{
+	struct usb_host_config *config = dev->actconfig;
+	int i;
+
+	if (!config)
+		return NULL;
+	for (i = 0; i < config->desc.bNumInterfaces; i++)
+		if (config->interface[i]->altsetting[0]
+				.desc.bInterfaceNumber == ifnum)
+			return config->interface[i];
+
+	return NULL;
+}
+
+/**
+ * usb_altnum_to_altsetting - get the altsetting structure with a given
+ *	alternate setting number.
+ * @intf: the interface containing the altsetting in question
+ * @altnum: the desired alternate setting number
+ *
+ * This searches the altsetting array of the specified interface for
+ * an entry with the correct bAlternateSetting value and returns a pointer
+ * to that entry, or null.
+ *
+ * Note that altsettings need not be stored sequentially by number, so
+ * it would be incorrect to assume that the first altsetting entry in
+ * the array corresponds to altsetting zero.  This routine helps device
+ * drivers avoid such mistakes.
+ *
+ * Don't call this function unless you are bound to the intf interface
+ * or you have locked the device!
+ */
+struct usb_host_interface *usb_altnum_to_altsetting(struct usb_interface *intf,
+		unsigned int altnum)
+{
+	int i;
+
+	for (i = 0; i < intf->num_altsetting; i++) {
+		if (intf->altsetting[i].desc.bAlternateSetting == altnum)
+			return &intf->altsetting[i];
+	}
+	return NULL;
+}
+
+/**
+ * usb_driver_claim_interface - bind a driver to an interface
+ * @driver: the driver to be bound
+ * @iface: the interface to which it will be bound; must be in the
+ *	usb device's active configuration
+ * @priv: driver data associated with that interface
+ *
+ * This is used by usb device drivers that need to claim more than one
+ * interface on a device when probing (audio and acm are current examples).
+ * No device driver should directly modify internal usb_interface or
+ * usb_device structure members.
+ *
+ * Few drivers should need to use this routine, since the most natural
+ * way to bind to an interface is to return the private data from
+ * the driver's probe() method.
+ *
+ * Callers must own the device lock and the driver model's usb_bus_type.subsys
+ * writelock.  So driver probe() entries don't need extra locking,
+ * but other call contexts may need to explicitly claim those locks.
+ */
+int usb_driver_claim_interface(struct usb_driver *driver,
+				struct usb_interface *iface, void* priv)
+{
+	struct device *dev = &iface->dev;
+
+	if (dev->driver)
+		return -EBUSY;
+
+	dev->driver = &driver->driver;
+	usb_set_intfdata(iface, priv);
+	iface->condition = USB_INTERFACE_BOUND;
+
+	/* if interface was already added, bind now; else let
+	 * the future device_add() bind it, bypassing probe()
+	 */
+	if (!list_empty (&dev->bus_list))
+		device_bind_driver(dev);
+
+	return 0;
+}
+
+/**
+ * usb_driver_release_interface - unbind a driver from an interface
+ * @driver: the driver to be unbound
+ * @iface: the interface from which it will be unbound
+ *
+ * This can be used by drivers to release an interface without waiting
+ * for their disconnect() methods to be called.  In typical cases this
+ * also causes the driver disconnect() method to be called.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ * Callers must own the device lock and the driver model's usb_bus_type.subsys
+ * writelock.  So driver disconnect() entries don't need extra locking,
+ * but other call contexts may need to explicitly claim those locks.
+ */
+void usb_driver_release_interface(struct usb_driver *driver,
+					struct usb_interface *iface)
+{
+	struct device *dev = &iface->dev;
+
+	/* this should never happen, don't release something that's not ours */
+	if (!dev->driver || dev->driver != &driver->driver)
+		return;
+
+	/* don't disconnect from disconnect(), or before dev_add() */
+	if (!list_empty (&dev->driver_list) && !list_empty (&dev->bus_list))
+		device_release_driver(dev);
+
+	dev->driver = NULL;
+	usb_set_intfdata(iface, NULL);
+	iface->condition = USB_INTERFACE_UNBOUND;
+}
+
+/**
+ * usb_match_id - find first usb_device_id matching device or interface
+ * @interface: the interface of interest
+ * @id: array of usb_device_id structures, terminated by zero entry
+ *
+ * usb_match_id searches an array of usb_device_id's and returns
+ * the first one matching the device or interface, or null.
+ * This is used when binding (or rebinding) a driver to an interface.
+ * Most USB device drivers will use this indirectly, through the usb core,
+ * but some layered driver frameworks use it directly.
+ * These device tables are exported with MODULE_DEVICE_TABLE, through
+ * modutils and "modules.usbmap", to support the driver loading
+ * functionality of USB hotplugging.
+ *
+ * What Matches:
+ *
+ * The "match_flags" element in a usb_device_id controls which
+ * members are used.  If the corresponding bit is set, the
+ * value in the device_id must match its corresponding member
+ * in the device or interface descriptor, or else the device_id
+ * does not match.
+ *
+ * "driver_info" is normally used only by device drivers,
+ * but you can create a wildcard "matches anything" usb_device_id
+ * as a driver's "modules.usbmap" entry if you provide an id with
+ * only a nonzero "driver_info" field.  If you do this, the USB device
+ * driver's probe() routine should use additional intelligence to
+ * decide whether to bind to the specified interface.
+ * 
+ * What Makes Good usb_device_id Tables:
+ *
+ * The match algorithm is very simple, so that intelligence in
+ * driver selection must come from smart driver id records.
+ * Unless you have good reasons to use another selection policy,
+ * provide match elements only in related groups, and order match
+ * specifiers from specific to general.  Use the macros provided
+ * for that purpose if you can.
+ *
+ * The most specific match specifiers use device descriptor
+ * data.  These are commonly used with product-specific matches;
+ * the USB_DEVICE macro lets you provide vendor and product IDs,
+ * and you can also match against ranges of product revisions.
+ * These are widely used for devices with application or vendor
+ * specific bDeviceClass values.
+ *
+ * Matches based on device class/subclass/protocol specifications
+ * are slightly more general; use the USB_DEVICE_INFO macro, or
+ * its siblings.  These are used with single-function devices
+ * where bDeviceClass doesn't specify that each interface has
+ * its own class. 
+ *
+ * Matches based on interface class/subclass/protocol are the
+ * most general; they let drivers bind to any interface on a
+ * multiple-function device.  Use the USB_INTERFACE_INFO
+ * macro, or its siblings, to match class-per-interface style 
+ * devices (as recorded in bDeviceClass).
+ *  
+ * Within those groups, remember that not all combinations are
+ * meaningful.  For example, don't give a product version range
+ * without vendor and product IDs; or specify a protocol without
+ * its associated class and subclass.
+ */   
+const struct usb_device_id *
+usb_match_id(struct usb_interface *interface, const struct usb_device_id *id)
+{
+	struct usb_host_interface *intf;
+	struct usb_device *dev;
+
+	/* proc_connectinfo in devio.c may call us with id == NULL. */
+	if (id == NULL)
+		return NULL;
+
+	intf = interface->cur_altsetting;
+	dev = interface_to_usbdev(interface);
+
+	/* It is important to check that id->driver_info is nonzero,
+	   since an entry that is all zeroes except for a nonzero
+	   id->driver_info is the way to create an entry that
+	   indicates that the driver want to examine every
+	   device and interface. */
+	for (; id->idVendor || id->bDeviceClass || id->bInterfaceClass ||
+	       id->driver_info; id++) {
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
+		    id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
+		    id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
+			continue;
+
+		/* No need to test id->bcdDevice_lo != 0, since 0 is never
+		   greater than any unsigned number. */
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
+		    (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
+		    (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
+		    (id->bDeviceClass != dev->descriptor.bDeviceClass))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
+		    (id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
+		    (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
+		    (id->bInterfaceClass != intf->desc.bInterfaceClass))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
+		    (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
+			continue;
+
+		if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
+		    (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
+			continue;
+
+		return id;
+	}
+
+	return NULL;
+}
+
+/**
+ * usb_find_interface - find usb_interface pointer for driver and device
+ * @drv: the driver whose current configuration is considered
+ * @minor: the minor number of the desired device
+ *
+ * This walks the driver device list and returns a pointer to the interface 
+ * with the matching minor.  Note, this only works for devices that share the
+ * USB major number.
+ */
+struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
+{
+	struct list_head *entry;
+	struct device *dev;
+	struct usb_interface *intf;
+
+	list_for_each(entry, &drv->driver.devices) {
+		dev = container_of(entry, struct device, driver_list);
+
+		/* can't look at usb devices, only interfaces */
+		if (dev->driver == &usb_generic_driver)
+			continue;
+
+		intf = to_usb_interface(dev);
+		if (intf->minor == -1)
+			continue;
+		if (intf->minor == minor)
+			return intf;
+	}
+
+	/* no device found that matches */
+	return NULL;	
+}
+
+static int usb_device_match (struct device *dev, struct device_driver *drv)
+{
+	struct usb_interface *intf;
+	struct usb_driver *usb_drv;
+	const struct usb_device_id *id;
+
+	/* check for generic driver, which we don't match any device with */
+	if (drv == &usb_generic_driver)
+		return 0;
+
+	intf = to_usb_interface(dev);
+	usb_drv = to_usb_driver(drv);
+	
+	id = usb_match_id (intf, usb_drv->id_table);
+	if (id)
+		return 1;
+
+	return 0;
+}
+
+
+#ifdef	CONFIG_HOTPLUG
+
+/*
+ * USB hotplugging invokes what /proc/sys/kernel/hotplug says
+ * (normally /sbin/hotplug) when USB devices get added or removed.
+ *
+ * This invokes a user mode policy agent, typically helping to load driver
+ * or other modules, configure the device, and more.  Drivers can provide
+ * a MODULE_DEVICE_TABLE to help with module loading subtasks.
+ *
+ * We're called either from khubd (the typical case) or from root hub
+ * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
+ * delays in event delivery.  Use sysfs (and DEVPATH) to make sure the
+ * device (and this configuration!) are still present.
+ */
+static int usb_hotplug (struct device *dev, char **envp, int num_envp,
+			char *buffer, int buffer_size)
+{
+	struct usb_interface *intf;
+	struct usb_device *usb_dev;
+	int i = 0;
+	int length = 0;
+
+	if (!dev)
+		return -ENODEV;
+
+	/* driver is often null here; dev_dbg() would oops */
+	pr_debug ("usb %s: hotplug\n", dev->bus_id);
+
+	/* Must check driver_data here, as on remove driver is always NULL */
+	if ((dev->driver == &usb_generic_driver) || 
+	    (dev->driver_data == &usb_generic_driver_data))
+		return 0;
+
+	intf = to_usb_interface(dev);
+	usb_dev = interface_to_usbdev (intf);
+	
+	if (usb_dev->devnum < 0) {
+		pr_debug ("usb %s: already deleted?\n", dev->bus_id);
+		return -ENODEV;
+	}
+	if (!usb_dev->bus) {
+		pr_debug ("usb %s: bus removed?\n", dev->bus_id);
+		return -ENODEV;
+	}
+
+#ifdef	CONFIG_USB_DEVICEFS
+	/* If this is available, userspace programs can directly read
+	 * all the device descriptors we don't tell them about.  Or
+	 * even act as usermode drivers.
+	 *
+	 * FIXME reduce hardwired intelligence here
+	 */
+	if (add_hotplug_env_var(envp, num_envp, &i,
+				buffer, buffer_size, &length,
+				"DEVICE=/proc/bus/usb/%03d/%03d",
+				usb_dev->bus->busnum, usb_dev->devnum))
+		return -ENOMEM;
+#endif
+
+	/* per-device configurations are common */
+	if (add_hotplug_env_var(envp, num_envp, &i,
+				buffer, buffer_size, &length,
+				"PRODUCT=%x/%x/%x",
+				le16_to_cpu(usb_dev->descriptor.idVendor),
+				le16_to_cpu(usb_dev->descriptor.idProduct),
+				le16_to_cpu(usb_dev->descriptor.bcdDevice)))
+		return -ENOMEM;
+
+	/* class-based driver binding models */
+	if (add_hotplug_env_var(envp, num_envp, &i,
+				buffer, buffer_size, &length,
+				"TYPE=%d/%d/%d",
+				usb_dev->descriptor.bDeviceClass,
+				usb_dev->descriptor.bDeviceSubClass,
+				usb_dev->descriptor.bDeviceProtocol))
+		return -ENOMEM;
+
+	if (usb_dev->descriptor.bDeviceClass == 0) {
+		struct usb_host_interface *alt = intf->cur_altsetting;
+
+		/* 2.4 only exposed interface zero.  in 2.5, hotplug
+		 * agents are called for all interfaces, and can use
+		 * $DEVPATH/bInterfaceNumber if necessary.
+		 */
+		if (add_hotplug_env_var(envp, num_envp, &i,
+					buffer, buffer_size, &length,
+					"INTERFACE=%d/%d/%d",
+					alt->desc.bInterfaceClass,
+					alt->desc.bInterfaceSubClass,
+					alt->desc.bInterfaceProtocol))
+			return -ENOMEM;
+
+		if (add_hotplug_env_var(envp, num_envp, &i,
+					buffer, buffer_size, &length,
+					"MODALIAS=usb:v%04Xp%04Xdl%04Xdh%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
+					le16_to_cpu(usb_dev->descriptor.idVendor),
+					le16_to_cpu(usb_dev->descriptor.idProduct),
+					le16_to_cpu(usb_dev->descriptor.bcdDevice),
+					le16_to_cpu(usb_dev->descriptor.bcdDevice),
+					usb_dev->descriptor.bDeviceClass,
+					usb_dev->descriptor.bDeviceSubClass,
+					usb_dev->descriptor.bDeviceProtocol,
+					alt->desc.bInterfaceClass,
+					alt->desc.bInterfaceSubClass,
+					alt->desc.bInterfaceProtocol))
+			return -ENOMEM;
+ 	} else {
+		if (add_hotplug_env_var(envp, num_envp, &i,
+					buffer, buffer_size, &length,
+					"MODALIAS=usb:v%04Xp%04Xdl%04Xdh%04Xdc%02Xdsc%02Xdp%02Xic*isc*ip*",
+					le16_to_cpu(usb_dev->descriptor.idVendor),
+					le16_to_cpu(usb_dev->descriptor.idProduct),
+					le16_to_cpu(usb_dev->descriptor.bcdDevice),
+					le16_to_cpu(usb_dev->descriptor.bcdDevice),
+					usb_dev->descriptor.bDeviceClass,
+					usb_dev->descriptor.bDeviceSubClass,
+					usb_dev->descriptor.bDeviceProtocol))
+			return -ENOMEM;
+	}
+
+	envp[i] = NULL;
+
+	return 0;
+}
+
+#else
+
+static int usb_hotplug (struct device *dev, char **envp,
+			int num_envp, char *buffer, int buffer_size)
+{
+	return -ENODEV;
+}
+
+#endif	/* CONFIG_HOTPLUG */
+
+/**
+ * usb_release_dev - free a usb device structure when all users of it are finished.
+ * @dev: device that's been disconnected
+ *
+ * Will be called only by the device core when all users of this usb device are
+ * done.
+ */
+static void usb_release_dev(struct device *dev)
+{
+	struct usb_device *udev;
+
+	udev = to_usb_device(dev);
+
+	usb_destroy_configuration(udev);
+	usb_bus_put(udev->bus);
+	kfree(udev->product);
+	kfree(udev->manufacturer);
+	kfree(udev->serial);
+	kfree(udev);
+}
+
+/**
+ * usb_alloc_dev - usb device constructor (usbcore-internal)
+ * @parent: hub to which device is connected; null to allocate a root hub
+ * @bus: bus used to access the device
+ * @port1: one-based index of port; ignored for root hubs
+ * Context: !in_interrupt ()
+ *
+ * Only hub drivers (including virtual root hub drivers for host
+ * controllers) should ever call this.
+ *
+ * This call may not be used in a non-sleeping context.
+ */
+struct usb_device *
+usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
+{
+	struct usb_device *dev;
+
+	dev = kmalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	memset(dev, 0, sizeof(*dev));
+
+	bus = usb_bus_get(bus);
+	if (!bus) {
+		kfree(dev);
+		return NULL;
+	}
+
+	device_initialize(&dev->dev);
+	dev->dev.bus = &usb_bus_type;
+	dev->dev.dma_mask = bus->controller->dma_mask;
+	dev->dev.driver_data = &usb_generic_driver_data;
+	dev->dev.driver = &usb_generic_driver;
+	dev->dev.release = usb_release_dev;
+	dev->state = USB_STATE_ATTACHED;
+
+	INIT_LIST_HEAD(&dev->ep0.urb_list);
+	dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
+	dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
+	/* ep0 maxpacket comes later, from device descriptor */
+	dev->ep_in[0] = dev->ep_out[0] = &dev->ep0;
+
+	/* Save readable and stable topology id, distinguishing devices
+	 * by location for diagnostics, tools, driver model, etc.  The
+	 * string is a path along hub ports, from the root.  Each device's
+	 * dev->devpath will be stable until USB is re-cabled, and hubs
+	 * are often labeled with these port numbers.  The bus_id isn't
+	 * as stable:  bus->busnum changes easily from modprobe order,
+	 * cardbus or pci hotplugging, and so on.
+	 */
+	if (unlikely (!parent)) {
+		dev->devpath [0] = '0';
+
+		dev->dev.parent = bus->controller;
+		sprintf (&dev->dev.bus_id[0], "usb%d", bus->busnum);
+	} else {
+		/* match any labeling on the hubs; it's one-based */
+		if (parent->devpath [0] == '0')
+			snprintf (dev->devpath, sizeof dev->devpath,
+				"%d", port1);
+		else
+			snprintf (dev->devpath, sizeof dev->devpath,
+				"%s.%d", parent->devpath, port1);
+
+		dev->dev.parent = &parent->dev;
+		sprintf (&dev->dev.bus_id[0], "%d-%s",
+			bus->busnum, dev->devpath);
+
+		/* hub driver sets up TT records */
+	}
+
+	dev->bus = bus;
+	dev->parent = parent;
+	INIT_LIST_HEAD(&dev->filelist);
+
+	init_MUTEX(&dev->serialize);
+
+	return dev;
+}
+
+/**
+ * usb_get_dev - increments the reference count of the usb device structure
+ * @dev: the device being referenced
+ *
+ * Each live reference to a device should be refcounted.
+ *
+ * Drivers for USB interfaces should normally record such references in
+ * their probe() methods, when they bind to an interface, and release
+ * them by calling usb_put_dev(), in their disconnect() methods.
+ *
+ * A pointer to the device with the incremented reference counter is returned.
+ */
+struct usb_device *usb_get_dev(struct usb_device *dev)
+{
+	if (dev)
+		get_device(&dev->dev);
+	return dev;
+}
+
+/**
+ * usb_put_dev - release a use of the usb device structure
+ * @dev: device that's been disconnected
+ *
+ * Must be called when a user of a device is finished with it.  When the last
+ * user of the device calls this function, the memory of the device is freed.
+ */
+void usb_put_dev(struct usb_device *dev)
+{
+	if (dev)
+		put_device(&dev->dev);
+}
+
+/**
+ * usb_get_intf - increments the reference count of the usb interface structure
+ * @intf: the interface being referenced
+ *
+ * Each live reference to a interface must be refcounted.
+ *
+ * Drivers for USB interfaces should normally record such references in
+ * their probe() methods, when they bind to an interface, and release
+ * them by calling usb_put_intf(), in their disconnect() methods.
+ *
+ * A pointer to the interface with the incremented reference counter is
+ * returned.
+ */
+struct usb_interface *usb_get_intf(struct usb_interface *intf)
+{
+	if (intf)
+		get_device(&intf->dev);
+	return intf;
+}
+
+/**
+ * usb_put_intf - release a use of the usb interface structure
+ * @intf: interface that's been decremented
+ *
+ * Must be called when a user of an interface is finished with it.  When the
+ * last user of the interface calls this function, the memory of the interface
+ * is freed.
+ */
+void usb_put_intf(struct usb_interface *intf)
+{
+	if (intf)
+		put_device(&intf->dev);
+}
+
+
+/*			USB device locking
+ *
+ * Although locking USB devices should be straightforward, it is
+ * complicated by the way the driver-model core works.  When a new USB
+ * driver is registered or unregistered, the core will automatically
+ * probe or disconnect all matching interfaces on all USB devices while
+ * holding the USB subsystem writelock.  There's no good way for us to
+ * tell which devices will be used or to lock them beforehand; our only
+ * option is to effectively lock all the USB devices.
+ *
+ * We do that by using a private rw-semaphore, usb_all_devices_rwsem.
+ * When locking an individual device you must first acquire the rwsem's
+ * readlock.  When a driver is registered or unregistered the writelock
+ * must be held.  These actions are encapsulated in the subroutines
+ * below, so all a driver needs to do is call usb_lock_device() and
+ * usb_unlock_device().
+ *
+ * Complications arise when several devices are to be locked at the same
+ * time.  Only hub-aware drivers that are part of usbcore ever have to
+ * do this; nobody else needs to worry about it.  The problem is that
+ * usb_lock_device() must not be called to lock a second device since it
+ * would acquire the rwsem's readlock reentrantly, leading to deadlock if
+ * another thread was waiting for the writelock.  The solution is simple:
+ *
+ *	When locking more than one device, call usb_lock_device()
+ *	to lock the first one.  Lock the others by calling
+ *	down(&udev->serialize) directly.
+ *
+ *	When unlocking multiple devices, use up(&udev->serialize)
+ *	to unlock all but the last one.  Unlock the last one by
+ *	calling usb_unlock_device().
+ *
+ *	When locking both a device and its parent, always lock the
+ *	the parent first.
+ */
+
+/**
+ * usb_lock_device - acquire the lock for a usb device structure
+ * @udev: device that's being locked
+ *
+ * Use this routine when you don't hold any other device locks;
+ * to acquire nested inner locks call down(&udev->serialize) directly.
+ * This is necessary for proper interaction with usb_lock_all_devices().
+ */
+void usb_lock_device(struct usb_device *udev)
+{
+	down_read(&usb_all_devices_rwsem);
+	down(&udev->serialize);
+}
+
+/**
+ * usb_trylock_device - attempt to acquire the lock for a usb device structure
+ * @udev: device that's being locked
+ *
+ * Don't use this routine if you already hold a device lock;
+ * use down_trylock(&udev->serialize) instead.
+ * This is necessary for proper interaction with usb_lock_all_devices().
+ *
+ * Returns 1 if successful, 0 if contention.
+ */
+int usb_trylock_device(struct usb_device *udev)
+{
+	if (!down_read_trylock(&usb_all_devices_rwsem))
+		return 0;
+	if (down_trylock(&udev->serialize)) {
+		up_read(&usb_all_devices_rwsem);
+		return 0;
+	}
+	return 1;
+}
+
+/**
+ * usb_lock_device_for_reset - cautiously acquire the lock for a
+ *	usb device structure
+ * @udev: device that's being locked
+ * @iface: interface bound to the driver making the request (optional)
+ *
+ * Attempts to acquire the device lock, but fails if the device is
+ * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
+ * is neither BINDING nor BOUND.  Rather than sleeping to wait for the
+ * lock, the routine polls repeatedly.  This is to prevent deadlock with
+ * disconnect; in some drivers (such as usb-storage) the disconnect()
+ * callback will block waiting for a device reset to complete.
+ *
+ * Returns a negative error code for failure, otherwise 1 or 0 to indicate
+ * that the device will or will not have to be unlocked.  (0 can be
+ * returned when an interface is given and is BINDING, because in that
+ * case the driver already owns the device lock.)
+ */
+int usb_lock_device_for_reset(struct usb_device *udev,
+		struct usb_interface *iface)
+{
+	if (udev->state == USB_STATE_NOTATTACHED)
+		return -ENODEV;
+	if (udev->state == USB_STATE_SUSPENDED)
+		return -EHOSTUNREACH;
+	if (iface) {
+		switch (iface->condition) {
+		  case USB_INTERFACE_BINDING:
+			return 0;
+		  case USB_INTERFACE_BOUND:
+			break;
+		  default:
+			return -EINTR;
+		}
+	}
+
+	while (!usb_trylock_device(udev)) {
+		msleep(15);
+		if (udev->state == USB_STATE_NOTATTACHED)
+			return -ENODEV;
+		if (udev->state == USB_STATE_SUSPENDED)
+			return -EHOSTUNREACH;
+		if (iface && iface->condition != USB_INTERFACE_BOUND)
+			return -EINTR;
+	}
+	return 1;
+}
+
+/**
+ * usb_unlock_device - release the lock for a usb device structure
+ * @udev: device that's being unlocked
+ *
+ * Use this routine when releasing the only device lock you hold;
+ * to release inner nested locks call up(&udev->serialize) directly.
+ * This is necessary for proper interaction with usb_lock_all_devices().
+ */
+void usb_unlock_device(struct usb_device *udev)
+{
+	up(&udev->serialize);
+	up_read(&usb_all_devices_rwsem);
+}
+
+/**
+ * usb_lock_all_devices - acquire the lock for all usb device structures
+ *
+ * This is necessary when registering a new driver or probing a bus,
+ * since the driver-model core may try to use any usb_device.
+ */
+void usb_lock_all_devices(void)
+{
+	down_write(&usb_all_devices_rwsem);
+}
+
+/**
+ * usb_unlock_all_devices - release the lock for all usb device structures
+ */
+void usb_unlock_all_devices(void)
+{
+	up_write(&usb_all_devices_rwsem);
+}
+
+
+static struct usb_device *match_device(struct usb_device *dev,
+				       u16 vendor_id, u16 product_id)
+{
+	struct usb_device *ret_dev = NULL;
+	int child;
+
+	dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
+	    le16_to_cpu(dev->descriptor.idVendor),
+	    le16_to_cpu(dev->descriptor.idProduct));
+
+	/* see if this device matches */
+	if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
+	    (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
+		dev_dbg (&dev->dev, "matched this device!\n");
+		ret_dev = usb_get_dev(dev);
+		goto exit;
+	}
+
+	/* look through all of the children of this device */
+	for (child = 0; child < dev->maxchild; ++child) {
+		if (dev->children[child]) {
+			down(&dev->children[child]->serialize);
+			ret_dev = match_device(dev->children[child],
+					       vendor_id, product_id);
+			up(&dev->children[child]->serialize);
+			if (ret_dev)
+				goto exit;
+		}
+	}
+exit:
+	return ret_dev;
+}
+
+/**
+ * usb_find_device - find a specific usb device in the system
+ * @vendor_id: the vendor id of the device to find
+ * @product_id: the product id of the device to find
+ *
+ * Returns a pointer to a struct usb_device if such a specified usb
+ * device is present in the system currently.  The usage count of the
+ * device will be incremented if a device is found.  Make sure to call
+ * usb_put_dev() when the caller is finished with the device.
+ *
+ * If a device with the specified vendor and product id is not found,
+ * NULL is returned.
+ */
+struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
+{
+	struct list_head *buslist;
+	struct usb_bus *bus;
+	struct usb_device *dev = NULL;
+	
+	down(&usb_bus_list_lock);
+	for (buslist = usb_bus_list.next;
+	     buslist != &usb_bus_list; 
+	     buslist = buslist->next) {
+		bus = container_of(buslist, struct usb_bus, bus_list);
+		if (!bus->root_hub)
+			continue;
+		usb_lock_device(bus->root_hub);
+		dev = match_device(bus->root_hub, vendor_id, product_id);
+		usb_unlock_device(bus->root_hub);
+		if (dev)
+			goto exit;
+	}
+exit:
+	up(&usb_bus_list_lock);
+	return dev;
+}
+
+/**
+ * usb_get_current_frame_number - return current bus frame number
+ * @dev: the device whose bus is being queried
+ *
+ * Returns the current frame number for the USB host controller
+ * used with the given USB device.  This can be used when scheduling
+ * isochronous requests.
+ *
+ * Note that different kinds of host controller have different
+ * "scheduling horizons".  While one type might support scheduling only
+ * 32 frames into the future, others could support scheduling up to
+ * 1024 frames into the future.
+ */
+int usb_get_current_frame_number(struct usb_device *dev)
+{
+	return dev->bus->op->get_frame_number (dev);
+}
+
+/*-------------------------------------------------------------------*/
+/*
+ * __usb_get_extra_descriptor() finds a descriptor of specific type in the
+ * extra field of the interface and endpoint descriptor structs.
+ */
+
+int __usb_get_extra_descriptor(char *buffer, unsigned size,
+	unsigned char type, void **ptr)
+{
+	struct usb_descriptor_header *header;
+
+	while (size >= sizeof(struct usb_descriptor_header)) {
+		header = (struct usb_descriptor_header *)buffer;
+
+		if (header->bLength < 2) {
+			printk(KERN_ERR
+				"%s: bogus descriptor, type %d length %d\n",
+				usbcore_name,
+				header->bDescriptorType, 
+				header->bLength);
+			return -1;
+		}
+
+		if (header->bDescriptorType == type) {
+			*ptr = header;
+			return 0;
+		}
+
+		buffer += header->bLength;
+		size -= header->bLength;
+	}
+	return -1;
+}
+
+/**
+ * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
+ * @dev: device the buffer will be used with
+ * @size: requested buffer size
+ * @mem_flags: affect whether allocation may block
+ * @dma: used to return DMA address of buffer
+ *
+ * Return value is either null (indicating no buffer could be allocated), or
+ * the cpu-space pointer to a buffer that may be used to perform DMA to the
+ * specified device.  Such cpu-space buffers are returned along with the DMA
+ * address (through the pointer provided).
+ *
+ * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
+ * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
+ * mapping hardware for long idle periods.  The implementation varies between
+ * platforms, depending on details of how DMA will work to this device.
+ * Using these buffers also helps prevent cacheline sharing problems on
+ * architectures where CPU caches are not DMA-coherent.
+ *
+ * When the buffer is no longer used, free it with usb_buffer_free().
+ */
+void *usb_buffer_alloc (
+	struct usb_device *dev,
+	size_t size,
+	int mem_flags,
+	dma_addr_t *dma
+)
+{
+	if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_alloc)
+		return NULL;
+	return dev->bus->op->buffer_alloc (dev->bus, size, mem_flags, dma);
+}
+
+/**
+ * usb_buffer_free - free memory allocated with usb_buffer_alloc()
+ * @dev: device the buffer was used with
+ * @size: requested buffer size
+ * @addr: CPU address of buffer
+ * @dma: DMA address of buffer
+ *
+ * This reclaims an I/O buffer, letting it be reused.  The memory must have
+ * been allocated using usb_buffer_alloc(), and the parameters must match
+ * those provided in that allocation request. 
+ */
+void usb_buffer_free (
+	struct usb_device *dev,
+	size_t size,
+	void *addr,
+	dma_addr_t dma
+)
+{
+	if (!dev || !dev->bus || !dev->bus->op || !dev->bus->op->buffer_free)
+	    	return;
+	dev->bus->op->buffer_free (dev->bus, size, addr, dma);
+}
+
+/**
+ * usb_buffer_map - create DMA mapping(s) for an urb
+ * @urb: urb whose transfer_buffer/setup_packet will be mapped
+ *
+ * Return value is either null (indicating no buffer could be mapped), or
+ * the parameter.  URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
+ * added to urb->transfer_flags if the operation succeeds.  If the device
+ * is connected to this system through a non-DMA controller, this operation
+ * always succeeds.
+ *
+ * This call would normally be used for an urb which is reused, perhaps
+ * as the target of a large periodic transfer, with usb_buffer_dmasync()
+ * calls to synchronize memory and dma state.
+ *
+ * Reverse the effect of this call with usb_buffer_unmap().
+ */
+#if 0
+struct urb *usb_buffer_map (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!urb
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(controller = bus->controller))
+		return NULL;
+
+	if (controller->dma_mask) {
+		urb->transfer_dma = dma_map_single (controller,
+			urb->transfer_buffer, urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+		if (usb_pipecontrol (urb->pipe))
+			urb->setup_dma = dma_map_single (controller,
+					urb->setup_packet,
+					sizeof (struct usb_ctrlrequest),
+					DMA_TO_DEVICE);
+	// FIXME generic api broken like pci, can't report errors
+	// if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
+	} else
+		urb->transfer_dma = ~0;
+	urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
+				| URB_NO_SETUP_DMA_MAP);
+	return urb;
+}
+#endif  /*  0  */
+
+/* XXX DISABLED, no users currently.  If you wish to re-enable this
+ * XXX please determine whether the sync is to transfer ownership of
+ * XXX the buffer from device to cpu or vice verse, and thusly use the
+ * XXX appropriate _for_{cpu,device}() method.  -DaveM
+ */
+#if 0
+
+/**
+ * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
+ * @urb: urb whose transfer_buffer/setup_packet will be synchronized
+ */
+void usb_buffer_dmasync (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!urb
+			|| !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(controller = bus->controller))
+		return;
+
+	if (controller->dma_mask) {
+		dma_sync_single (controller,
+			urb->transfer_dma, urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+		if (usb_pipecontrol (urb->pipe))
+			dma_sync_single (controller,
+					urb->setup_dma,
+					sizeof (struct usb_ctrlrequest),
+					DMA_TO_DEVICE);
+	}
+}
+#endif
+
+/**
+ * usb_buffer_unmap - free DMA mapping(s) for an urb
+ * @urb: urb whose transfer_buffer will be unmapped
+ *
+ * Reverses the effect of usb_buffer_map().
+ */
+#if 0
+void usb_buffer_unmap (struct urb *urb)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!urb
+			|| !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
+			|| !urb->dev
+			|| !(bus = urb->dev->bus)
+			|| !(controller = bus->controller))
+		return;
+
+	if (controller->dma_mask) {
+		dma_unmap_single (controller,
+			urb->transfer_dma, urb->transfer_buffer_length,
+			usb_pipein (urb->pipe)
+				? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+		if (usb_pipecontrol (urb->pipe))
+			dma_unmap_single (controller,
+					urb->setup_dma,
+					sizeof (struct usb_ctrlrequest),
+					DMA_TO_DEVICE);
+	}
+	urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
+				| URB_NO_SETUP_DMA_MAP);
+}
+#endif  /*  0  */
+
+/**
+ * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
+ * @dev: device to which the scatterlist will be mapped
+ * @pipe: endpoint defining the mapping direction
+ * @sg: the scatterlist to map
+ * @nents: the number of entries in the scatterlist
+ *
+ * Return value is either < 0 (indicating no buffers could be mapped), or
+ * the number of DMA mapping array entries in the scatterlist.
+ *
+ * The caller is responsible for placing the resulting DMA addresses from
+ * the scatterlist into URB transfer buffer pointers, and for setting the
+ * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
+ *
+ * Top I/O rates come from queuing URBs, instead of waiting for each one
+ * to complete before starting the next I/O.   This is particularly easy
+ * to do with scatterlists.  Just allocate and submit one URB for each DMA
+ * mapping entry returned, stopping on the first error or when all succeed.
+ * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
+ *
+ * This call would normally be used when translating scatterlist requests,
+ * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
+ * may be able to coalesce mappings for improved I/O efficiency.
+ *
+ * Reverse the effect of this call with usb_buffer_unmap_sg().
+ */
+int usb_buffer_map_sg (struct usb_device *dev, unsigned pipe,
+		struct scatterlist *sg, int nents)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!dev
+			|| usb_pipecontrol (pipe)
+			|| !(bus = dev->bus)
+			|| !(controller = bus->controller)
+			|| !controller->dma_mask)
+		return -1;
+
+	// FIXME generic api broken like pci, can't report errors
+	return dma_map_sg (controller, sg, nents,
+			usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+}
+
+/* XXX DISABLED, no users currently.  If you wish to re-enable this
+ * XXX please determine whether the sync is to transfer ownership of
+ * XXX the buffer from device to cpu or vice verse, and thusly use the
+ * XXX appropriate _for_{cpu,device}() method.  -DaveM
+ */
+#if 0
+
+/**
+ * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
+ * @dev: device to which the scatterlist will be mapped
+ * @pipe: endpoint defining the mapping direction
+ * @sg: the scatterlist to synchronize
+ * @n_hw_ents: the positive return value from usb_buffer_map_sg
+ *
+ * Use this when you are re-using a scatterlist's data buffers for
+ * another USB request.
+ */
+void usb_buffer_dmasync_sg (struct usb_device *dev, unsigned pipe,
+		struct scatterlist *sg, int n_hw_ents)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!dev
+			|| !(bus = dev->bus)
+			|| !(controller = bus->controller)
+			|| !controller->dma_mask)
+		return;
+
+	dma_sync_sg (controller, sg, n_hw_ents,
+			usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+}
+#endif
+
+/**
+ * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
+ * @dev: device to which the scatterlist will be mapped
+ * @pipe: endpoint defining the mapping direction
+ * @sg: the scatterlist to unmap
+ * @n_hw_ents: the positive return value from usb_buffer_map_sg
+ *
+ * Reverses the effect of usb_buffer_map_sg().
+ */
+void usb_buffer_unmap_sg (struct usb_device *dev, unsigned pipe,
+		struct scatterlist *sg, int n_hw_ents)
+{
+	struct usb_bus		*bus;
+	struct device		*controller;
+
+	if (!dev
+			|| !(bus = dev->bus)
+			|| !(controller = bus->controller)
+			|| !controller->dma_mask)
+		return;
+
+	dma_unmap_sg (controller, sg, n_hw_ents,
+			usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
+}
+
+static int usb_generic_suspend(struct device *dev, u32 state)
+{
+	struct usb_interface *intf;
+	struct usb_driver *driver;
+
+	if (dev->driver == &usb_generic_driver)
+		return usb_suspend_device (to_usb_device(dev), state);
+
+	if ((dev->driver == NULL) ||
+	    (dev->driver_data == &usb_generic_driver_data))
+		return 0;
+
+	intf = to_usb_interface(dev);
+	driver = to_usb_driver(dev->driver);
+
+	/* there's only one USB suspend state */
+	if (intf->dev.power.power_state)
+		return 0;
+
+	if (driver->suspend)
+		return driver->suspend(intf, state);
+	return 0;
+}
+
+static int usb_generic_resume(struct device *dev)
+{
+	struct usb_interface *intf;
+	struct usb_driver *driver;
+
+	/* devices resume through their hub */
+	if (dev->driver == &usb_generic_driver)
+		return usb_resume_device (to_usb_device(dev));
+
+	if ((dev->driver == NULL) ||
+	    (dev->driver_data == &usb_generic_driver_data))
+		return 0;
+
+	intf = to_usb_interface(dev);
+	driver = to_usb_driver(dev->driver);
+
+	if (driver->resume)
+		return driver->resume(intf);
+	return 0;
+}
+
+struct bus_type usb_bus_type = {
+	.name =		"usb",
+	.match =	usb_device_match,
+	.hotplug =	usb_hotplug,
+	.suspend =	usb_generic_suspend,
+	.resume =	usb_generic_resume,
+};
+
+#ifndef MODULE
+
+static int __init usb_setup_disable(char *str)
+{
+	nousb = 1;
+	return 1;
+}
+
+/* format to disable USB on kernel command line is: nousb */
+__setup("nousb", usb_setup_disable);
+
+#endif
+
+/*
+ * for external read access to <nousb>
+ */
+int usb_disabled(void)
+{
+	return nousb;
+}
+
+/*
+ * Init
+ */
+static int __init usb_init(void)
+{
+	int retval;
+	if (nousb) {
+		pr_info ("%s: USB support disabled\n", usbcore_name);
+		return 0;
+	}
+
+	retval = bus_register(&usb_bus_type);
+	if (retval) 
+		goto out;
+	retval = usb_host_init();
+	if (retval)
+		goto host_init_failed;
+	retval = usb_major_init();
+	if (retval)
+		goto major_init_failed;
+	retval = usbfs_init();
+	if (retval)
+		goto fs_init_failed;
+	retval = usb_hub_init();
+	if (retval)
+		goto hub_init_failed;
+
+	retval = driver_register(&usb_generic_driver);
+	if (!retval)
+		goto out;
+
+	usb_hub_cleanup();
+hub_init_failed:
+	usbfs_cleanup();
+fs_init_failed:
+	usb_major_cleanup();	
+major_init_failed:
+	usb_host_cleanup();
+host_init_failed:
+	bus_unregister(&usb_bus_type);
+out:
+	return retval;
+}
+
+/*
+ * Cleanup
+ */
+static void __exit usb_exit(void)
+{
+	/* This will matter if shutdown/reboot does exitcalls. */
+	if (nousb)
+		return;
+
+	driver_unregister(&usb_generic_driver);
+	usb_major_cleanup();
+	usbfs_cleanup();
+	usb_hub_cleanup();
+	usb_host_cleanup();
+	bus_unregister(&usb_bus_type);
+}
+
+subsys_initcall(usb_init);
+module_exit(usb_exit);
+
+/*
+ * USB may be built into the kernel or be built as modules.
+ * These symbols are exported for device (or host controller)
+ * driver modules to use.
+ */
+
+EXPORT_SYMBOL(usb_register);
+EXPORT_SYMBOL(usb_deregister);
+EXPORT_SYMBOL(usb_disabled);
+
+EXPORT_SYMBOL(usb_alloc_dev);
+EXPORT_SYMBOL(usb_put_dev);
+EXPORT_SYMBOL(usb_get_dev);
+EXPORT_SYMBOL(usb_hub_tt_clear_buffer);
+
+EXPORT_SYMBOL(usb_lock_device);
+EXPORT_SYMBOL(usb_trylock_device);
+EXPORT_SYMBOL(usb_lock_device_for_reset);
+EXPORT_SYMBOL(usb_unlock_device);
+
+EXPORT_SYMBOL(usb_driver_claim_interface);
+EXPORT_SYMBOL(usb_driver_release_interface);
+EXPORT_SYMBOL(usb_match_id);
+EXPORT_SYMBOL(usb_find_interface);
+EXPORT_SYMBOL(usb_ifnum_to_if);
+EXPORT_SYMBOL(usb_altnum_to_altsetting);
+
+EXPORT_SYMBOL(usb_reset_device);
+EXPORT_SYMBOL(usb_disconnect);
+
+EXPORT_SYMBOL(__usb_get_extra_descriptor);
+
+EXPORT_SYMBOL(usb_find_device);
+EXPORT_SYMBOL(usb_get_current_frame_number);
+
+EXPORT_SYMBOL (usb_buffer_alloc);
+EXPORT_SYMBOL (usb_buffer_free);
+
+#if 0
+EXPORT_SYMBOL (usb_buffer_map);
+EXPORT_SYMBOL (usb_buffer_dmasync);
+EXPORT_SYMBOL (usb_buffer_unmap);
+#endif
+
+EXPORT_SYMBOL (usb_buffer_map_sg);
+#if 0
+EXPORT_SYMBOL (usb_buffer_dmasync_sg);
+#endif
+EXPORT_SYMBOL (usb_buffer_unmap_sg);
+
+MODULE_LICENSE("GPL");