diff options
Diffstat (limited to 'drivers/usb/core/usb.c')
| -rw-r--r-- | drivers/usb/core/usb.c | 1573 |
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"); |