#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>
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)
-{
- 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;
-}
-
-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__);
-
- /* 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;
-}
-
-/**
- * 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
mark_quiesced(iface);
}
-/**
- * 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)
-{
- 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;
-}
-
+struct find_interface_arg {
+ int minor;
+ struct usb_interface *interface;
+};
static int __find_interface(struct device * dev, void * data)
{
- struct usb_interface ** ret = (struct usb_interface **)data;
- struct usb_interface * intf = *ret;
- int *minor = (int *)data;
+ struct find_interface_arg *arg = data;
+ struct usb_interface *intf;
/* can't look at usb devices, only interfaces */
if (dev->driver == &usb_generic_driver)
return 0;
intf = to_usb_interface(dev);
- if (intf->minor != -1 && intf->minor == *minor) {
- *ret = intf;
+ if (intf->minor != -1 && intf->minor == arg->minor) {
+ arg->interface = intf;
return 1;
}
return 0;
*/
struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
{
- struct usb_interface *intf = (struct usb_interface *)(long)minor;
- int ret;
-
- ret = driver_for_each_device(&drv->driver, NULL, &intf, __find_interface);
-
- return ret ? intf : 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;
+ struct find_interface_arg argb;
- return 0;
+ argb.minor = minor;
+ argb.interface = NULL;
+ driver_for_each_device(&drv->driver, NULL, &argb, __find_interface);
+ return argb.interface;
}
-
#ifdef CONFIG_HOTPLUG
/*
/* hub driver sets up TT records */
}
+ dev->portnum = port1;
dev->bus = bus;
dev->parent = parent;
INIT_LIST_HEAD(&dev->filelist);
- init_MUTEX(&dev->serialize);
-
return 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().
+ * USB devices and interfaces are locked using the semaphore in their
+ * embedded struct device. The hub driver guarantees that whenever a
+ * device is connected or disconnected, drivers are called with the
+ * USB device locked as well as their particular interface.
*
* 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().
+ * do this; nobody else needs to worry about it. The rule for locking
+ * is simple:
*
* 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
}
}
- while (!usb_trylock_device(udev)) {
+ while (usb_trylock_device(udev) != 0) {
/* If we can't acquire the lock after waiting one second,
* we're probably deadlocked */
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)
/* 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);
+ usb_lock_device(dev->children[child]);
ret_dev = match_device(dev->children[child],
vendor_id, product_id);
- up(&dev->children[child]->serialize);
+ usb_unlock_device(dev->children[child]);
if (ret_dev)
goto exit;
}
.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
+__module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444);
/*
* for external read access to <nousb>
* driver modules to use.
*/
-EXPORT_SYMBOL(usb_register);
-EXPORT_SYMBOL(usb_deregister);
EXPORT_SYMBOL(usb_disabled);
EXPORT_SYMBOL_GPL(usb_get_intf);
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);
git.openpandora.org / pandora-kernel.git / blobdiff