/*
* 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 2000-2001 (kernel hotplug, usb_device_id,
more docs, etc)
* (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/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);
int nousb; /* Disable USB when built into kernel image */
/* Not honored on modular build */
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 = {
.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 */
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;
/* driver claim() doesn't yet affect dev->driver... */
if (intf->driver)
return error;
id = usb_match_id (intf, driver->id_table);
if (id) {
dev_dbg (dev, "%s - got id\n", __FUNCTION__);
error = driver->probe (intf, id);
}
if (!error)
intf->driver = driver;
return error;
}
/* called from driver core with usb_bus_type.subsys writelock */
int usb_unbind_interface(struct device *dev)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_driver *driver = intf->driver;
/* 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->driver = NULL;
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;
retval = driver_register(&new_driver->driver);
if (!retval) {
info("registered new driver %s", new_driver->name);
usbfs_update_special();
} else {
err("problem %d when registering driver %s",
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)
{
info("deregistering driver %s", driver->name);
driver_unregister (&driver->driver);
usbfs_update_special();
}
/**
* usb_ifnum_to_if - get the interface object with a given interface number (usbcore-internal)
* @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.
*/
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_epnum_to_ep_desc - get the endpoint object with a given endpoint number
* @dev: the device whose current configuration+altsettings is considered
* @epnum: the desired endpoint, masked with USB_DIR_IN as appropriate.
*
* This walks the device descriptor for the currently active configuration,
* and returns a pointer to the endpoint with that particular endpoint
* number, or null.
*
* Note that interface descriptors are not required to list endpoint
* numbers in any standardized order, so that it would be wrong to
* assume that ep2in precedes either ep5in, ep2out, or even ep1out.
* This routine helps device drivers avoid such mistakes.
*/
struct usb_endpoint_descriptor *
usb_epnum_to_ep_desc(struct usb_device *dev, unsigned epnum)
{
struct usb_host_config *config = dev->actconfig;
int i, k;
if (!config)
return NULL;
for (i = 0; i < config->desc.bNumInterfaces; i++) {
struct usb_interface *intf;
struct usb_host_interface *alt;
/* only endpoints in current altsetting are active */
intf = config->interface[i];
alt = intf->altsetting + intf->act_altsetting;
for (k = 0; k < alt->desc.bNumEndpoints; k++)
if (epnum == alt->endpoint[k].desc.bEndpointAddress)
return &alt->endpoint[k].desc;
}
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
* @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 driver model's usb bus writelock. So driver
* probe() entries don't need extra locking, but other call contexts
* may need to explicitly claim that lock.
*/
int usb_driver_claim_interface(struct usb_driver *driver, struct usb_interface *iface, void* priv)
{
if (!iface || !driver)
return -EINVAL;
if (iface->driver)
return -EBUSY;
/* FIXME should device_bind_driver() */
iface->driver = driver;
usb_set_intfdata(iface, priv);
return 0;
}
/**
* usb_interface_claimed - returns true iff an interface is claimed
* @iface: the interface being checked
*
* This should be used by drivers to check other interfaces to see if
* they are available or not. If another driver has claimed the interface,
* they may not claim it. Otherwise it's OK to claim it using
* usb_driver_claim_interface().
*
* Returns true (nonzero) iff the interface is claimed, else false (zero).
*/
int usb_interface_claimed(struct usb_interface *iface)
{
if (!iface)
return 0;
return (iface->driver != NULL);
} /* usb_interface_claimed() */
/**
* 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
*
* In addition to unbinding the driver, this re-initializes the interface
* by selecting altsetting 0, the default alternate setting.
*
* This can be used by drivers to release an interface without waiting
* for their disconnect() methods to be called.
*
* When the USB subsystem disconnect()s a driver from some interface,
* it automatically invokes this method for that interface. That
* means that even drivers that used usb_driver_claim_interface()
* usually won't need to call this.
*
* This call is synchronous, and may not be used in an interrupt context.
* Callers must own the driver model's usb bus writelock. So driver
* disconnect() entries don't need extra locking, but other call contexts
* may need to explicitly claim that lock.
*/
void usb_driver_release_interface(struct usb_driver *driver, struct usb_interface *iface)
{
/* this should never happen, don't release something that's not ours */
if (!iface || !iface->driver || iface->driver != driver)
return;
if (iface->dev.driver) {
/* FIXME should be the ONLY case here */
device_release_driver(&iface->dev);
return;
}
usb_set_interface(interface_to_usbdev(iface),
iface->altsetting[0].desc.bInterfaceNumber,
0);
usb_set_intfdata(iface, NULL);
iface->driver = NULL;
}
/**
* 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->altsetting [interface->act_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 != dev->descriptor.idVendor)
continue;
if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
id->idProduct != 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 > dev->descriptor.bcdDevice))
continue;
if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
(id->bcdDevice_hi < 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_drv->id_table;
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;
char *scratch;
int i = 0;
int length = 0;
dbg ("%s", __FUNCTION__);
if (!dev)
return -ENODEV;
/* 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) {
dbg ("device already deleted ??");
return -ENODEV;
}
if (!usb_dev->bus) {
dbg ("bus already removed?");
return -ENODEV;
}
scratch = buffer;
#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
*/
envp [i++] = scratch;
length += snprintf (scratch, buffer_size - length,
"DEVICE=/proc/bus/usb/%03d/%03d",
usb_dev->bus->busnum, usb_dev->devnum);
if ((buffer_size - length <= 0) || (i >= num_envp))
return -ENOMEM;
++length;
scratch += length;
#endif
/* per-device configurations are common */
envp [i++] = scratch;
length += snprintf (scratch, buffer_size - length, "PRODUCT=%x/%x/%x",
usb_dev->descriptor.idVendor,
usb_dev->descriptor.idProduct,
usb_dev->descriptor.bcdDevice);
if ((buffer_size - length <= 0) || (i >= num_envp))
return -ENOMEM;
++length;
scratch += length;
/* class-based driver binding models */
envp [i++] = scratch;
length += snprintf (scratch, buffer_size - length, "TYPE=%d/%d/%d",
usb_dev->descriptor.bDeviceClass,
usb_dev->descriptor.bDeviceSubClass,
usb_dev->descriptor.bDeviceProtocol);
if ((buffer_size - length <= 0) || (i >= num_envp))
return -ENOMEM;
++length;
scratch += length;
if (usb_dev->descriptor.bDeviceClass == 0) {
int alt = intf->act_altsetting;
/* 2.4 only exposed interface zero. in 2.5, hotplug
* agents are called for all interfaces, and can use
* $DEVPATH/bInterfaceNumber if necessary.
*/
envp [i++] = scratch;
length += snprintf (scratch, buffer_size - length,
"INTERFACE=%d/%d/%d",
intf->altsetting[alt].desc.bInterfaceClass,
intf->altsetting[alt].desc.bInterfaceSubClass,
intf->altsetting[alt].desc.bInterfaceProtocol);
if ((buffer_size - length <= 0) || (i >= num_envp))
return -ENOMEM;
++length;
scratch += length;
}
envp [i++] = 0;
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);
if (udev->bus && udev->bus->op && udev->bus->op->deallocate)
udev->bus->op->deallocate(udev);
usb_destroy_configuration(udev);
usb_bus_put(udev->bus);
kfree (udev);
}
/**
* usb_alloc_dev - allocate a usb device structure (usbcore-internal)
* @parent: hub to which device is connected
* @bus: bus used to access the device
* Context: !in_interrupt ()
*
* Only hub drivers (including virtual root hub drivers for host
* controllers) should ever call this.
*
* This call is synchronous, and may not be used in an interrupt context.
*/
struct usb_device *usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus)
{
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.release = usb_release_dev;
dev->state = USB_STATE_ATTACHED;
if (!parent)
dev->devpath [0] = '0';
dev->bus = bus;
dev->parent = parent;
INIT_LIST_HEAD(&dev->filelist);
init_MUTEX(&dev->serialize);
if (dev->bus->op->allocate)
dev->bus->op->allocate(dev);
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)
{
struct device *tmp;
if (!dev)
return NULL;
tmp = get_device(&dev->dev);
if (tmp)
return to_usb_device(tmp);
else
return NULL;
}
/**
* 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);
}
static struct usb_device *match_device(struct usb_device *dev,
u16 vendor_id, u16 product_id)
{
struct usb_device *ret_dev = NULL;
int child;
dbg("looking at vendor %d, product %d",
dev->descriptor.idVendor,
dev->descriptor.idProduct);
/* see if this device matches */
if ((dev->descriptor.idVendor == vendor_id) &&
(dev->descriptor.idProduct == product_id)) {
dbg ("found the device!");
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]) {
ret_dev = match_device(dev->children[child],
vendor_id, product_id);
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);
dev = match_device(bus->root_hub, vendor_id, product_id);
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) {
err("invalid descriptor length of %d", header->bLength);
return -1;
}
if (header->bDescriptorType == type) {
*ptr = header;
return 0;
}
buffer += header->bLength;
size -= header->bLength;
}
return -1;
}
/**
* usb_disconnect - disconnect a device (usbcore-internal)
* @pdev: pointer to device being disconnected
* Context: !in_interrupt ()
*
* Something got disconnected. Get rid of it, and all of its children.
*
* Only hub drivers (including virtual root hub drivers for host
* controllers) should ever call this.
*
* This call is synchronous, and may not be used in an interrupt context.
*/
void usb_disconnect(struct usb_device **pdev)
{
struct usb_device *dev = *pdev;
struct usb_bus *bus;
struct usb_operations *ops;
int i;
might_sleep ();
if (!dev) {
pr_debug ("%s nodev\n", __FUNCTION__);
return;
}
bus = dev->bus;
if (!bus) {
pr_debug ("%s nobus\n", __FUNCTION__);
return;
}
ops = bus->op;
*pdev = NULL;
/* mark the device as inactive, so any further urb submissions for
* this device will fail.
*/
dev->state = USB_STATE_NOTATTACHED;
down(&dev->serialize);
dev_info (&dev->dev, "USB disconnect, address %d\n", dev->devnum);
/* Free up all the children before we remove this device */
for (i = 0; i < USB_MAXCHILDREN; i++) {
struct usb_device **child = dev->children + i;
if (*child)
usb_disconnect(child);
}
/* deallocate hcd/hardware state ... nuking all pending urbs and
* cleaning up all state associated with the current configuration
*/
usb_disable_device(dev, 0);
dev_dbg (&dev->dev, "unregistering device\n");
/* Free the device number and remove the /proc/bus/usb entry */
if (dev->devnum > 0) {
clear_bit(dev->devnum, dev->bus->devmap.devicemap);
usbfs_remove_device(dev);
}
up(&dev->serialize);
device_unregister(&dev->dev);
}
/**
* usb_choose_address - pick device address (usbcore-internal)
* @dev: newly detected device (in DEFAULT state)
*
* Picks a device address. It's up to the hub (or root hub) driver
* to handle and manage enumeration, starting from the DEFAULT state.
* Only hub drivers (but not virtual root hub drivers for host
* controllers) should ever call this.
*/
void usb_choose_address(struct usb_device *dev)
{
int devnum;
// FIXME needs locking for SMP!!
/* why? this is called only from the hub thread,
* which hopefully doesn't run on multiple CPU's simultaneously 8-)
*/
/* Try to allocate the next devnum beginning at bus->devnum_next. */
devnum = find_next_zero_bit(dev->bus->devmap.devicemap, 128, dev->bus->devnum_next);
if (devnum >= 128)
devnum = find_next_zero_bit(dev->bus->devmap.devicemap, 128, 1);
dev->bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
if (devnum < 128) {
set_bit(devnum, dev->bus->devmap.devicemap);
dev->devnum = devnum;
}
}
// hub-only!! ... and only exported for reset/reinit path.
// otherwise used internally, for usb_new_device()
int usb_set_address(struct usb_device *dev)
{
int retval;
if (dev->devnum == 0)
return -EINVAL;
if (dev->state != USB_STATE_DEFAULT && dev->state != USB_STATE_ADDRESS)
return -EINVAL;
retval = usb_control_msg(dev, usb_snddefctrl(dev), USB_REQ_SET_ADDRESS,
0, dev->devnum, 0, NULL, 0, HZ * USB_CTRL_SET_TIMEOUT);
if (retval == 0)
dev->state = USB_STATE_ADDRESS;
return retval;
}
/*
* By the time we get here, we chose a new device address
* and is in the default state. We need to identify the thing and
* get the ball rolling..
*
* Returns 0 for success, != 0 for error.
*
* This call is synchronous, and may not be used in an interrupt context.
*
* Only the hub driver should ever call this; root hub registration
* uses it only indirectly.
*/
#define NEW_DEVICE_RETRYS 2
#define SET_ADDRESS_RETRYS 2
int usb_new_device(struct usb_device *dev, struct device *parent)
{
int err = -EINVAL;
int i;
int j;
int config;
/*
* Set the driver for the usb device to point to the "generic" driver.
* This prevents the main usb device from being sent to the usb bus
* probe function. Yes, it's a hack, but a nice one :)
*
* Do it asap, so more driver model stuff (like the device.h message
* utilities) can be used in hcd submit/unlink code paths.
*/
usb_generic_driver.bus = &usb_bus_type;
dev->dev.parent = parent;
dev->dev.driver = &usb_generic_driver;
dev->dev.bus = &usb_bus_type;
dev->dev.driver_data = &usb_generic_driver_data;
if (dev->dev.bus_id[0] == 0)
sprintf (&dev->dev.bus_id[0], "%d-%s",
dev->bus->busnum, dev->devpath);
/* dma masks come from the controller; readonly, except to hcd */
dev->dev.dma_mask = parent->dma_mask;
/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
* it's fixed size except for full speed devices.
*/
switch (dev->speed) {
case USB_SPEED_HIGH: /* fixed at 64 */
i = 64;
break;
case USB_SPEED_FULL: /* 8, 16, 32, or 64 */
/* to determine the ep0 maxpacket size, read the first 8
* bytes from the device descriptor to get bMaxPacketSize0;
* then correct our initial (small) guess.
*/
// FALLTHROUGH
case USB_SPEED_LOW: /* fixed at 8 */
i = 8;
break;
default:
goto fail;
}
dev->epmaxpacketin [0] = i;
dev->epmaxpacketout[0] = i;
for (i = 0; i < NEW_DEVICE_RETRYS; ++i) {
for (j = 0; j < SET_ADDRESS_RETRYS; ++j) {
err = usb_set_address(dev);
if (err >= 0)
break;
wait_ms(200);
}
if (err < 0) {
dev_err(&dev->dev,
"device not accepting address %d, error %d\n",
dev->devnum, err);
goto fail;
}
wait_ms(10); /* Let the SET_ADDRESS settle */
/* high and low speed devices don't need this... */
err = usb_get_device_descriptor(dev, 8);
if (err >= 8)
break;
wait_ms(100);
}
if (err < 8) {
dev_err(&dev->dev, "device descriptor read/8, error %d\n", err);
goto fail;
}
if (dev->speed == USB_SPEED_FULL) {
usb_disable_endpoint(dev, 0);
usb_endpoint_running(dev, 0, 1);
usb_endpoint_running(dev, 0, 0);
dev->epmaxpacketin [0] = dev->descriptor.bMaxPacketSize0;
dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
}
/* USB device state == addressed ... still not usable */
err = usb_get_device_descriptor(dev, sizeof(dev->descriptor));
if (err != (signed)sizeof(dev->descriptor)) {
dev_err(&dev->dev, "device descriptor read/all, error %d\n", err);
goto fail;
}
err = usb_get_configuration(dev);
if (err < 0) {
dev_err(&dev->dev, "can't read configurations, error %d\n",
err);
goto fail;
}
/* Tell the world! */
dev_dbg(&dev->dev, "new device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
dev->descriptor.iManufacturer, dev->descriptor.iProduct, dev->descriptor.iSerialNumber);
#ifdef DEBUG
if (dev->descriptor.iProduct)
usb_show_string(dev, "Product", dev->descriptor.iProduct);
if (dev->descriptor.iManufacturer)
usb_show_string(dev, "Manufacturer", dev->descriptor.iManufacturer);
if (dev->descriptor.iSerialNumber)
usb_show_string(dev, "SerialNumber", dev->descriptor.iSerialNumber);
#endif
/* put device-specific files into sysfs */
err = device_add (&dev->dev);
if (err) {
dev_err(&dev->dev, "can't device_add, error %d\n", err);
goto fail;
}
usb_create_driverfs_dev_files (dev);
/* choose and set the configuration. that registers the interfaces
* with the driver core, and lets usb device drivers bind to them.
* NOTE: should interact with hub power budgeting.
*/
config = dev->config[0].desc.bConfigurationValue;
if (dev->descriptor.bNumConfigurations != 1) {
for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
/* heuristic: Linux is more likely to have class
* drivers, so avoid vendor-specific interfaces.
*/
if (dev->config[i].interface[0]->altsetting
->desc.bInterfaceClass
== USB_CLASS_VENDOR_SPEC)
continue;
config = dev->config[i].desc.bConfigurationValue;
break;
}
dev_info(&dev->dev,
"configuration #%d chosen from %d choices\n",
config,
dev->descriptor.bNumConfigurations);
}
err = usb_set_configuration(dev, config);
if (err) {
dev_err(&dev->dev, "can't set config #%d, error %d\n",
config, err);
device_del(&dev->dev);
goto fail;
}
/* USB device state == configured ... usable */
/* add a /proc/bus/usb entry */
usbfs_add_device(dev);
return 0;
fail:
dev->state = USB_STATE_DEFAULT;
clear_bit(dev->devnum, dev->bus->devmap.devicemap);
dev->devnum = -1;
return err;
}
/**
* 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 0;
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().
*/
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 0;
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;
}
/**
* 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);
}
}
/**
* 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().
*/
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);
}
/**
* 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);
}
/**
* 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);
}
/**
* 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_device_suspend(struct device *dev, u32 state)
{
struct usb_interface *intf;
struct usb_driver *driver;
if ((dev->driver == NULL) ||
(dev->driver == &usb_generic_driver) ||
(dev->driver_data == &usb_generic_driver_data))
return 0;
intf = to_usb_interface(dev);
driver = to_usb_driver(dev->driver);
if (driver->suspend)
return driver->suspend(intf, state);
return 0;
}
static int usb_device_resume(struct device *dev)
{
struct usb_interface *intf;
struct usb_driver *driver;
if ((dev->driver == NULL) ||
(dev->driver == &usb_generic_driver) ||
(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_device_suspend,
.resume = usb_device_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)
{
if (nousb) {
info("USB support disabled\n");
return 0;
}
bus_register(&usb_bus_type);
usb_host_init();
usb_major_init();
usbfs_init();
usb_hub_init();
driver_register(&usb_generic_driver);
return 0;
}
/*
* 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_epnum_to_ep_desc);
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_driver_claim_interface);
EXPORT_SYMBOL(usb_interface_claimed);
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_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);
EXPORT_SYMBOL (usb_buffer_map);
EXPORT_SYMBOL (usb_buffer_dmasync);
EXPORT_SYMBOL (usb_buffer_unmap);
EXPORT_SYMBOL (usb_buffer_map_sg);
EXPORT_SYMBOL (usb_buffer_dmasync_sg);
EXPORT_SYMBOL (usb_buffer_unmap_sg);
MODULE_LICENSE("GPL");
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