drivers/usb/core/driver.c - maze/linux - Git at Google

 /*
  * drivers/usb/driver.c - most of the driver model stuff for usb
  *
  * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
  *
  * based on drivers/usb/usb.c which had the following copyrights:
  *	(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..
  *
  */

 #include <linux/config.h>
 #include <linux/device.h>
 #include <linux/usb.h>
 #include "hcd.h"
 #include "usb.h"

 static int usb_match_one_id(struct usb_interface *interface,
 			    const struct usb_device_id *id);

 struct usb_dynid {
 	struct list_head node;
 	struct usb_device_id id;
 };


 static int generic_probe(struct device *dev)
 {
 	return 0;
 }
 static int generic_remove(struct device *dev)
 {
 	struct usb_device *udev = to_usb_device(dev);

 	/* if this is only an unbind, not a physical disconnect, then
 	 * unconfigure the device */
 	if (udev->state == USB_STATE_CONFIGURED)
 		usb_set_configuration(udev, 0);

 	/* in case the call failed or the device was suspended */
 	if (udev->state >= USB_STATE_CONFIGURED)
 		usb_disable_device(udev, 0);
 	return 0;
 }

 struct device_driver usb_generic_driver = {
 	.owner = THIS_MODULE,
 	.name =	"usb",
 	.bus = &usb_bus_type,
 	.probe = generic_probe,
 	.remove = generic_remove,
 };

 /* Fun hack to determine if the struct device is a
  * usb device or a usb interface. */
 int usb_generic_driver_data;

 #ifdef CONFIG_HOTPLUG

 /*
  * Adds a new dynamic USBdevice ID to this driver,
  * and cause the driver to probe for all devices again.
  */
 static ssize_t store_new_id(struct device_driver *driver,
 			    const char *buf, size_t count)
 {
 	struct usb_driver *usb_drv = to_usb_driver(driver);
 	struct usb_dynid *dynid;
 	u32 idVendor = 0;
 	u32 idProduct = 0;
 	int fields = 0;

 	fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
 	if (fields < 2)
 		return -EINVAL;

 	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
 	if (!dynid)
 		return -ENOMEM;

 	INIT_LIST_HEAD(&dynid->node);
 	dynid->id.idVendor = idVendor;
 	dynid->id.idProduct = idProduct;
 	dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;

 	spin_lock(&usb_drv->dynids.lock);
 	list_add_tail(&usb_drv->dynids.list, &dynid->node);
 	spin_unlock(&usb_drv->dynids.lock);

 	if (get_driver(driver)) {
 		driver_attach(driver);
 		put_driver(driver);
 	}

 	return count;
 }
 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);

 static int usb_create_newid_file(struct usb_driver *usb_drv)
 {
 	int error = 0;

 	if (usb_drv->no_dynamic_id)
 		goto exit;

 	if (usb_drv->probe != NULL)
 		error = sysfs_create_file(&usb_drv->driver.kobj,
 					  &driver_attr_new_id.attr);
 exit:
 	return error;
 }

 static void usb_remove_newid_file(struct usb_driver *usb_drv)
 {
 	if (usb_drv->no_dynamic_id)
 		return;

 	if (usb_drv->probe != NULL)
 		sysfs_remove_file(&usb_drv->driver.kobj,
 				  &driver_attr_new_id.attr);
 }

 static void usb_free_dynids(struct usb_driver *usb_drv)
 {
 	struct usb_dynid *dynid, *n;

 	spin_lock(&usb_drv->dynids.lock);
 	list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
 		list_del(&dynid->node);
 		kfree(dynid);
 	}
 	spin_unlock(&usb_drv->dynids.lock);
 }
 #else
 static inline int usb_create_newid_file(struct usb_driver *usb_drv)
 {
 	return 0;
 }

 static void usb_remove_newid_file(struct usb_driver *usb_drv)
 {
 }

 static inline void usb_free_dynids(struct usb_driver *usb_drv)
 {
 }
 #endif

 static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
 							struct usb_driver *drv)
 {
 	struct usb_dynid *dynid;

 	spin_lock(&drv->dynids.lock);
 	list_for_each_entry(dynid, &drv->dynids.list, node) {
 		if (usb_match_one_id(intf, &dynid->id)) {
 			spin_unlock(&drv->dynids.lock);
 			return &dynid->id;
 		}
 	}
 	spin_unlock(&drv->dynids.lock);
 	return NULL;
 }


 /* 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)
 		id = usb_match_dynamic_id(intf, driver);
 	if (id) {
 		dev_dbg(dev, "%s - got id\n", __FUNCTION__);

 		/* Interface "power state" doesn't correspond to any hardware
 		 * state whatsoever.  We use it to record when it's bound to
 		 * a driver that may start I/0:  it's not frozen/quiesced.
 		 */
 		mark_active(intf);
 		intf->condition = USB_INTERFACE_BINDING;
 		error = driver->probe(intf, id);
 		if (error) {
 			mark_quiesced(intf);
 			intf->condition = USB_INTERFACE_UNBOUND;
 		} else
 			intf->condition = 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;
 	mark_quiesced(intf);

 	return 0;
 }

 /* returns 0 if no match, 1 if match */
 static int usb_match_one_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 0;

 	intf = interface->cur_altsetting;
 	dev = interface_to_usbdev(interface);

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 	    id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
 	    id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
 		return 0;

 	/* 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)))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
 	    (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
 	    (id->bDeviceClass != dev->descriptor.bDeviceClass))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
 	    (id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
 	    (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
 	    (id->bInterfaceClass != intf->desc.bInterfaceClass))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
 	    (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
 		return 0;

 	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
 	    (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
 		return 0;

 	return 1;
 }
 /**
  * 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, 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)
 {
 	/* proc_connectinfo in devio.c may call us with id == NULL. */
 	if (id == NULL)
 		return NULL;

 	/* 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 (usb_match_one_id(interface, id))
 			return id;
 	}

 	return NULL;
 }
 EXPORT_SYMBOL(usb_match_id);

 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;

 	id = usb_match_dynamic_id(intf, usb_drv);
 	if (id)
 		return 1;
 	return 0;
 }

 /**
  * usb_register_driver - register a USB driver
  * @new_driver: USB operations for the driver
  * @owner: module owner of this 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_driver(struct usb_driver *new_driver, struct module *owner)
 {
 	int retval = 0;

 	if (usb_disabled())
 		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 = owner;
 	spin_lock_init(&new_driver->dynids.lock);
 	INIT_LIST_HEAD(&new_driver->dynids.list);

 	retval = driver_register(&new_driver->driver);

 	if (!retval) {
 		pr_info("%s: registered new driver %s\n",
 			usbcore_name, new_driver->name);
 		usbfs_update_special();
 		usb_create_newid_file(new_driver);
 	} else {
 		printk(KERN_ERR "%s: error %d registering driver %s\n",
 			usbcore_name, retval, new_driver->name);
 	}

 	return retval;
 }
 EXPORT_SYMBOL(usb_register_driver);

 /**
  * 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_remove_newid_file(driver);
 	usb_free_dynids(driver);
 	driver_unregister(&driver->driver);

 	usbfs_update_special();
 }
 EXPORT_SYMBOL(usb_deregister);
	/*
	* drivers/usb/driver.c - most of the driver model stuff for usb
	*
	* (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
	*
	* based on drivers/usb/usb.c which had the following copyrights:
	* (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..
	*
	*/

	#include <linux/config.h>
	#include <linux/device.h>
	#include <linux/usb.h>
	#include "hcd.h"
	#include "usb.h"

	static int usb_match_one_id(struct usb_interface *interface,
	const struct usb_device_id *id);

	struct usb_dynid {
	struct list_head node;
	struct usb_device_id id;
	};


	static int generic_probe(struct device *dev)
	{
	return 0;
	}
	static int generic_remove(struct device *dev)
	{
	struct usb_device *udev = to_usb_device(dev);

	/* if this is only an unbind, not a physical disconnect, then
	* unconfigure the device */
	if (udev->state == USB_STATE_CONFIGURED)
	usb_set_configuration(udev, 0);

	/* in case the call failed or the device was suspended */
	if (udev->state >= USB_STATE_CONFIGURED)
	usb_disable_device(udev, 0);
	return 0;
	}

	struct device_driver usb_generic_driver = {
	.owner = THIS_MODULE,
	.name = "usb",
	.bus = &usb_bus_type,
	.probe = generic_probe,
	.remove = generic_remove,
	};

	/* Fun hack to determine if the struct device is a
	* usb device or a usb interface. */
	int usb_generic_driver_data;

	#ifdef CONFIG_HOTPLUG

	/*
	* Adds a new dynamic USBdevice ID to this driver,
	* and cause the driver to probe for all devices again.
	*/
	static ssize_t store_new_id(struct device_driver *driver,
	const char *buf, size_t count)
	{
	struct usb_driver *usb_drv = to_usb_driver(driver);
	struct usb_dynid *dynid;
	u32 idVendor = 0;
	u32 idProduct = 0;
	int fields = 0;

	fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
	if (fields < 2)
	return -EINVAL;

	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
	if (!dynid)
	return -ENOMEM;

	INIT_LIST_HEAD(&dynid->node);
	dynid->id.idVendor = idVendor;
	dynid->id.idProduct = idProduct;
	dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;

	spin_lock(&usb_drv->dynids.lock);
	list_add_tail(&usb_drv->dynids.list, &dynid->node);
	spin_unlock(&usb_drv->dynids.lock);

	if (get_driver(driver)) {
	driver_attach(driver);
	put_driver(driver);
	}

	return count;
	}
	static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);

	static int usb_create_newid_file(struct usb_driver *usb_drv)
	{
	int error = 0;

	if (usb_drv->no_dynamic_id)
	goto exit;

	if (usb_drv->probe != NULL)
	error = sysfs_create_file(&usb_drv->driver.kobj,
	&driver_attr_new_id.attr);
	exit:
	return error;
	}

	static void usb_remove_newid_file(struct usb_driver *usb_drv)
	{
	if (usb_drv->no_dynamic_id)
	return;

	if (usb_drv->probe != NULL)
	sysfs_remove_file(&usb_drv->driver.kobj,
	&driver_attr_new_id.attr);
	}

	static void usb_free_dynids(struct usb_driver *usb_drv)
	{
	struct usb_dynid dynid, n;

	spin_lock(&usb_drv->dynids.lock);
	list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
	list_del(&dynid->node);
	kfree(dynid);
	}
	spin_unlock(&usb_drv->dynids.lock);
	}
	#else
	static inline int usb_create_newid_file(struct usb_driver *usb_drv)
	{
	return 0;
	}

	static void usb_remove_newid_file(struct usb_driver *usb_drv)
	{
	}

	static inline void usb_free_dynids(struct usb_driver *usb_drv)
	{
	}
	#endif

	static const struct usb_device_id usb_match_dynamic_id(struct usb_interface intf,
	struct usb_driver *drv)
	{
	struct usb_dynid *dynid;

	spin_lock(&drv->dynids.lock);
	list_for_each_entry(dynid, &drv->dynids.list, node) {
	if (usb_match_one_id(intf, &dynid->id)) {
	spin_unlock(&drv->dynids.lock);
	return &dynid->id;
	}
	}
	spin_unlock(&drv->dynids.lock);
	return NULL;
	}


	/* 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)
	id = usb_match_dynamic_id(intf, driver);
	if (id) {
	dev_dbg(dev, "%s - got id\n", __FUNCTION__);

	/* Interface "power state" doesn't correspond to any hardware
	* state whatsoever. We use it to record when it's bound to
	* a driver that may start I/0: it's not frozen/quiesced.
	*/
	mark_active(intf);
	intf->condition = USB_INTERFACE_BINDING;
	error = driver->probe(intf, id);
	if (error) {
	mark_quiesced(intf);
	intf->condition = USB_INTERFACE_UNBOUND;
	} else
	intf->condition = 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;
	mark_quiesced(intf);

	return 0;
	}

	/* returns 0 if no match, 1 if match */
	static int usb_match_one_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 0;

	intf = interface->cur_altsetting;
	dev = interface_to_usbdev(interface);

	if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
	id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
	id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
	return 0;

	/* 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)))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
	(id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
	(id->bDeviceClass != dev->descriptor.bDeviceClass))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
	(id->bDeviceSubClass!= dev->descriptor.bDeviceSubClass))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
	(id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
	(id->bInterfaceClass != intf->desc.bInterfaceClass))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
	(id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
	return 0;

	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
	(id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
	return 0;

	return 1;
	}
	/**
	* 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, 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)
	{
	/* proc_connectinfo in devio.c may call us with id == NULL. */
	if (id == NULL)
	return NULL;

	/* 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 (usb_match_one_id(interface, id))
	return id;
	}

	return NULL;
	}
	EXPORT_SYMBOL(usb_match_id);

	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;

	id = usb_match_dynamic_id(intf, usb_drv);
	if (id)
	return 1;
	return 0;
	}

	/**
	* usb_register_driver - register a USB driver
	* @new_driver: USB operations for the driver
	* @owner: module owner of this 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_driver(struct usb_driver new_driver, struct module owner)
	{
	int retval = 0;

	if (usb_disabled())
	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 = owner;
	spin_lock_init(&new_driver->dynids.lock);
	INIT_LIST_HEAD(&new_driver->dynids.list);

	retval = driver_register(&new_driver->driver);

	if (!retval) {
	pr_info("%s: registered new driver %s\n",
	usbcore_name, new_driver->name);
	usbfs_update_special();
	usb_create_newid_file(new_driver);
	} else {
	printk(KERN_ERR "%s: error %d registering driver %s\n",
	usbcore_name, retval, new_driver->name);
	}

	return retval;
	}
	EXPORT_SYMBOL(usb_register_driver);

	/**
	* 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_remove_newid_file(driver);
	usb_free_dynids(driver);
	driver_unregister(&driver->driver);

	usbfs_update_special();
	}
	EXPORT_SYMBOL(usb_deregister);