blob: 1f0db51190ccc79c121364de04a39a93c7e54aae [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Uwe Zeisbergerf30c2262006-10-03 23:01:26 +02002 * drivers/usb/core/usb.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * (C) Copyright Linus Torvalds 1999
5 * (C) Copyright Johannes Erdfelt 1999-2001
6 * (C) Copyright Andreas Gal 1999
7 * (C) Copyright Gregory P. Smith 1999
8 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9 * (C) Copyright Randy Dunlap 2000
10 * (C) Copyright David Brownell 2000-2004
11 * (C) Copyright Yggdrasil Computing, Inc. 2000
12 * (usb_device_id matching changes by Adam J. Richter)
13 * (C) Copyright Greg Kroah-Hartman 2002-2003
14 *
15 * NOTE! This is not actually a driver at all, rather this is
16 * just a collection of helper routines that implement the
17 * generic USB things that the real drivers can use..
18 *
19 * Think of this as a "USB library" rather than anything else.
20 * It should be considered a slave, with no callbacks. Callbacks
21 * are evil.
22 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/module.h>
Alan Sternb5e795f2007-02-20 15:00:53 -050025#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/string.h>
27#include <linux/bitops.h>
28#include <linux/slab.h>
29#include <linux/interrupt.h> /* for in_interrupt() */
30#include <linux/kmod.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <linux/errno.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/usb.h>
Arjan van de Ven4186ecf2006-01-11 15:55:29 +010035#include <linux/mutex.h>
Alan Sternbd859282006-09-19 10:14:07 -040036#include <linux/workqueue.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38#include <asm/io.h>
Adrian Bunk87ae9af2007-10-30 10:35:04 +010039#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <linux/mm.h>
41#include <linux/dma-mapping.h>
42
43#include "hcd.h"
44#include "usb.h"
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47const char *usbcore_name = "usbcore";
48
49static int nousb; /* Disable USB when built into kernel image */
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Alan Stern6b157c92007-03-13 16:37:30 -040051/* Workqueue for autosuspend and for remote wakeup of root hubs */
52struct workqueue_struct *ksuspend_usb_wq;
Alan Sternbd859282006-09-19 10:14:07 -040053
Alan Sternb5e795f2007-02-20 15:00:53 -050054#ifdef CONFIG_USB_SUSPEND
55static int usb_autosuspend_delay = 2; /* Default delay value,
56 * in seconds */
Alan Sterneaafbc32007-03-13 16:39:15 -040057module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
Alan Sternb5e795f2007-02-20 15:00:53 -050058MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
59
60#else
61#define usb_autosuspend_delay 0
62#endif
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Linus Torvalds1da177e2005-04-16 15:20:36 -070065/**
66 * usb_ifnum_to_if - get the interface object with a given interface number
67 * @dev: the device whose current configuration is considered
68 * @ifnum: the desired interface
69 *
70 * This walks the device descriptor for the currently active configuration
71 * and returns a pointer to the interface with that particular interface
72 * number, or null.
73 *
74 * Note that configuration descriptors are not required to assign interface
75 * numbers sequentially, so that it would be incorrect to assume that
76 * the first interface in that descriptor corresponds to interface zero.
77 * This routine helps device drivers avoid such mistakes.
78 * However, you should make sure that you do the right thing with any
79 * alternate settings available for this interfaces.
80 *
81 * Don't call this function unless you are bound to one of the interfaces
82 * on this device or you have locked the device!
83 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -030084struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
85 unsigned ifnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070086{
87 struct usb_host_config *config = dev->actconfig;
88 int i;
89
90 if (!config)
91 return NULL;
92 for (i = 0; i < config->desc.bNumInterfaces; i++)
93 if (config->interface[i]->altsetting[0]
94 .desc.bInterfaceNumber == ifnum)
95 return config->interface[i];
96
97 return NULL;
98}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -060099EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100
101/**
Randy Dunlapd0bcabc2008-02-29 22:03:07 -0800102 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 * @intf: the interface containing the altsetting in question
104 * @altnum: the desired alternate setting number
105 *
106 * This searches the altsetting array of the specified interface for
107 * an entry with the correct bAlternateSetting value and returns a pointer
108 * to that entry, or null.
109 *
110 * Note that altsettings need not be stored sequentially by number, so
111 * it would be incorrect to assume that the first altsetting entry in
112 * the array corresponds to altsetting zero. This routine helps device
113 * drivers avoid such mistakes.
114 *
115 * Don't call this function unless you are bound to the intf interface
116 * or you have locked the device!
117 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800118struct usb_host_interface *usb_altnum_to_altsetting(
119 const struct usb_interface *intf,
120 unsigned int altnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121{
122 int i;
123
124 for (i = 0; i < intf->num_altsetting; i++) {
125 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
126 return &intf->altsetting[i];
127 }
128 return NULL;
129}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600130EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800132struct find_interface_arg {
133 int minor;
134 struct usb_interface *interface;
135};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800137static int __find_interface(struct device *dev, void *data)
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800138{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800139 struct find_interface_arg *arg = data;
140 struct usb_interface *intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800141
142 /* can't look at usb devices, only interfaces */
Alan Stern8bb54ab2006-07-01 22:08:49 -0400143 if (is_usb_device(dev))
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800144 return 0;
145
146 intf = to_usb_interface(dev);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800147 if (intf->minor != -1 && intf->minor == arg->minor) {
148 arg->interface = intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800149 return 1;
150 }
151 return 0;
152}
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154/**
155 * usb_find_interface - find usb_interface pointer for driver and device
156 * @drv: the driver whose current configuration is considered
157 * @minor: the minor number of the desired device
158 *
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800159 * This walks the driver device list and returns a pointer to the interface
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 * with the matching minor. Note, this only works for devices that share the
161 * USB major number.
162 */
163struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
164{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800165 struct find_interface_arg argb;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700166 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800168 argb.minor = minor;
169 argb.interface = NULL;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700170 /* eat the error, it will be in argb.interface */
171 retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb,
172 __find_interface);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800173 return argb.interface;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600175EXPORT_SYMBOL_GPL(usb_find_interface);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177/**
178 * usb_release_dev - free a usb device structure when all users of it are finished.
179 * @dev: device that's been disconnected
180 *
181 * Will be called only by the device core when all users of this usb device are
182 * done.
183 */
184static void usb_release_dev(struct device *dev)
185{
186 struct usb_device *udev;
187
188 udev = to_usb_device(dev);
189
190 usb_destroy_configuration(udev);
Alan Stern17200582006-08-30 11:32:52 -0400191 usb_put_hcd(bus_to_hcd(udev->bus));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 kfree(udev->product);
193 kfree(udev->manufacturer);
194 kfree(udev->serial);
195 kfree(udev);
196}
197
Alan Stern4a9bee82007-11-06 15:01:52 -0500198#ifdef CONFIG_HOTPLUG
199static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
200{
201 struct usb_device *usb_dev;
202
203 usb_dev = to_usb_device(dev);
204
205 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
206 return -ENOMEM;
207
208 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
209 return -ENOMEM;
210
211 return 0;
212}
213
214#else
215
216static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
217{
218 return -ENODEV;
219}
220#endif /* CONFIG_HOTPLUG */
221
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100222struct device_type usb_device_type = {
223 .name = "usb_device",
224 .release = usb_release_dev,
Alan Stern4a9bee82007-11-06 15:01:52 -0500225 .uevent = usb_dev_uevent,
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100226};
227
Alan Stern645daaa2006-08-30 15:47:02 -0400228#ifdef CONFIG_PM
229
Alan Sternbd859282006-09-19 10:14:07 -0400230static int ksuspend_usb_init(void)
231{
Alan Stern7ed92f12007-05-22 09:38:39 -0400232 /* This workqueue is supposed to be both freezable and
233 * singlethreaded. Its job doesn't justify running on more
234 * than one CPU.
235 */
Rafael J. Wysocki7a8d37a2008-02-25 00:35:04 +0100236 ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
Alan Sternbd859282006-09-19 10:14:07 -0400237 if (!ksuspend_usb_wq)
238 return -ENOMEM;
239 return 0;
240}
241
242static void ksuspend_usb_cleanup(void)
243{
244 destroy_workqueue(ksuspend_usb_wq);
245}
246
Alan Sterndb063502006-11-13 15:02:04 -0500247#else
248
249#define ksuspend_usb_init() 0
250#define ksuspend_usb_cleanup() do {} while (0)
251
252#endif /* CONFIG_PM */
Alan Stern645daaa2006-08-30 15:47:02 -0400253
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700254
255/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
256static unsigned usb_bus_is_wusb(struct usb_bus *bus)
257{
258 struct usb_hcd *hcd = container_of(bus, struct usb_hcd, self);
259 return hcd->wireless;
260}
261
262
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263/**
264 * usb_alloc_dev - usb device constructor (usbcore-internal)
265 * @parent: hub to which device is connected; null to allocate a root hub
266 * @bus: bus used to access the device
267 * @port1: one-based index of port; ignored for root hubs
Oliver Neukum92516442007-01-23 15:55:28 -0500268 * Context: !in_interrupt()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 *
270 * Only hub drivers (including virtual root hub drivers for host
271 * controllers) should ever call this.
272 *
273 * This call may not be used in a non-sleeping context.
274 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800275struct usb_device *usb_alloc_dev(struct usb_device *parent,
276 struct usb_bus *bus, unsigned port1)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277{
278 struct usb_device *dev;
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700279 struct usb_hcd *usb_hcd = container_of(bus, struct usb_hcd, self);
280 unsigned root_hub = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
Alan Stern0a1ef3b2005-10-24 15:38:24 -0400282 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 if (!dev)
284 return NULL;
285
Alan Stern17200582006-08-30 11:32:52 -0400286 if (!usb_get_hcd(bus_to_hcd(bus))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 kfree(dev);
288 return NULL;
289 }
290
291 device_initialize(&dev->dev);
292 dev->dev.bus = &usb_bus_type;
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100293 dev->dev.type = &usb_device_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 dev->dev.dma_mask = bus->controller->dma_mask;
Yinghai Lu70f458f2007-07-09 12:03:09 -0700295 set_dev_node(&dev->dev, dev_to_node(bus->controller));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 dev->state = USB_STATE_ATTACHED;
Sarah Sharp4d59d8a2007-10-03 14:56:03 -0700297 atomic_set(&dev->urbnum, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298
299 INIT_LIST_HEAD(&dev->ep0.urb_list);
300 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
301 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
302 /* ep0 maxpacket comes later, from device descriptor */
Alan Sternbdd016b2007-07-30 17:05:22 -0400303 usb_enable_endpoint(dev, &dev->ep0);
Alan Stern6840d252007-09-10 11:34:26 -0400304 dev->can_submit = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305
306 /* Save readable and stable topology id, distinguishing devices
307 * by location for diagnostics, tools, driver model, etc. The
308 * string is a path along hub ports, from the root. Each device's
309 * dev->devpath will be stable until USB is re-cabled, and hubs
310 * are often labeled with these port numbers. The bus_id isn't
311 * as stable: bus->busnum changes easily from modprobe order,
312 * cardbus or pci hotplugging, and so on.
313 */
Oliver Neukum92516442007-01-23 15:55:28 -0500314 if (unlikely(!parent)) {
315 dev->devpath[0] = '0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316
317 dev->dev.parent = bus->controller;
Oliver Neukum92516442007-01-23 15:55:28 -0500318 sprintf(&dev->dev.bus_id[0], "usb%d", bus->busnum);
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700319 root_hub = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 } else {
321 /* match any labeling on the hubs; it's one-based */
Oliver Neukum92516442007-01-23 15:55:28 -0500322 if (parent->devpath[0] == '0')
323 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 "%d", port1);
325 else
Oliver Neukum92516442007-01-23 15:55:28 -0500326 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 "%s.%d", parent->devpath, port1);
328
329 dev->dev.parent = &parent->dev;
Oliver Neukum92516442007-01-23 15:55:28 -0500330 sprintf(&dev->dev.bus_id[0], "%d-%s",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 bus->busnum, dev->devpath);
332
333 /* hub driver sets up TT records */
334 }
335
Alan Stern12c3da32005-11-23 12:09:52 -0500336 dev->portnum = port1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 dev->bus = bus;
338 dev->parent = parent;
339 INIT_LIST_HEAD(&dev->filelist);
340
Alan Stern645daaa2006-08-30 15:47:02 -0400341#ifdef CONFIG_PM
342 mutex_init(&dev->pm_mutex);
David Howellsc4028952006-11-22 14:57:56 +0000343 INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
Alan Sternb5e795f2007-02-20 15:00:53 -0500344 dev->autosuspend_delay = usb_autosuspend_delay * HZ;
Sarah Sharp15123002007-12-21 16:54:15 -0800345 dev->connect_time = jiffies;
346 dev->active_duration = -jiffies;
Alan Stern645daaa2006-08-30 15:47:02 -0400347#endif
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700348 if (root_hub) /* Root hub always ok [and always wired] */
349 dev->authorized = 1;
350 else {
351 dev->authorized = usb_hcd->authorized_default;
352 dev->wusb = usb_bus_is_wusb(bus)? 1 : 0;
353 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return dev;
355}
356
357/**
358 * usb_get_dev - increments the reference count of the usb device structure
359 * @dev: the device being referenced
360 *
361 * Each live reference to a device should be refcounted.
362 *
363 * Drivers for USB interfaces should normally record such references in
364 * their probe() methods, when they bind to an interface, and release
365 * them by calling usb_put_dev(), in their disconnect() methods.
366 *
367 * A pointer to the device with the incremented reference counter is returned.
368 */
369struct usb_device *usb_get_dev(struct usb_device *dev)
370{
371 if (dev)
372 get_device(&dev->dev);
373 return dev;
374}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600375EXPORT_SYMBOL_GPL(usb_get_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376
377/**
378 * usb_put_dev - release a use of the usb device structure
379 * @dev: device that's been disconnected
380 *
381 * Must be called when a user of a device is finished with it. When the last
382 * user of the device calls this function, the memory of the device is freed.
383 */
384void usb_put_dev(struct usb_device *dev)
385{
386 if (dev)
387 put_device(&dev->dev);
388}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600389EXPORT_SYMBOL_GPL(usb_put_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
391/**
392 * usb_get_intf - increments the reference count of the usb interface structure
393 * @intf: the interface being referenced
394 *
395 * Each live reference to a interface must be refcounted.
396 *
397 * Drivers for USB interfaces should normally record such references in
398 * their probe() methods, when they bind to an interface, and release
399 * them by calling usb_put_intf(), in their disconnect() methods.
400 *
401 * A pointer to the interface with the incremented reference counter is
402 * returned.
403 */
404struct usb_interface *usb_get_intf(struct usb_interface *intf)
405{
406 if (intf)
407 get_device(&intf->dev);
408 return intf;
409}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600410EXPORT_SYMBOL_GPL(usb_get_intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411
412/**
413 * usb_put_intf - release a use of the usb interface structure
414 * @intf: interface that's been decremented
415 *
416 * Must be called when a user of an interface is finished with it. When the
417 * last user of the interface calls this function, the memory of the interface
418 * is freed.
419 */
420void usb_put_intf(struct usb_interface *intf)
421{
422 if (intf)
423 put_device(&intf->dev);
424}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600425EXPORT_SYMBOL_GPL(usb_put_intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
427/* USB device locking
428 *
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500429 * USB devices and interfaces are locked using the semaphore in their
430 * embedded struct device. The hub driver guarantees that whenever a
431 * device is connected or disconnected, drivers are called with the
432 * USB device locked as well as their particular interface.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 *
434 * Complications arise when several devices are to be locked at the same
435 * time. Only hub-aware drivers that are part of usbcore ever have to
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500436 * do this; nobody else needs to worry about it. The rule for locking
437 * is simple:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 *
439 * When locking both a device and its parent, always lock the
440 * the parent first.
441 */
442
443/**
Randy Dunlapd0bcabc2008-02-29 22:03:07 -0800444 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 * @udev: device that's being locked
446 * @iface: interface bound to the driver making the request (optional)
447 *
448 * Attempts to acquire the device lock, but fails if the device is
449 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
450 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
451 * lock, the routine polls repeatedly. This is to prevent deadlock with
452 * disconnect; in some drivers (such as usb-storage) the disconnect()
Alan Stern3ea15962005-08-11 10:15:39 -0400453 * or suspend() method will block waiting for a device reset to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 *
455 * Returns a negative error code for failure, otherwise 1 or 0 to indicate
456 * that the device will or will not have to be unlocked. (0 can be
457 * returned when an interface is given and is BINDING, because in that
458 * case the driver already owns the device lock.)
459 */
460int usb_lock_device_for_reset(struct usb_device *udev,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300461 const struct usb_interface *iface)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462{
Alan Stern3ea15962005-08-11 10:15:39 -0400463 unsigned long jiffies_expire = jiffies + HZ;
464
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 if (udev->state == USB_STATE_NOTATTACHED)
466 return -ENODEV;
467 if (udev->state == USB_STATE_SUSPENDED)
468 return -EHOSTUNREACH;
469 if (iface) {
470 switch (iface->condition) {
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800471 case USB_INTERFACE_BINDING:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 return 0;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800473 case USB_INTERFACE_BOUND:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 break;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800475 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 return -EINTR;
477 }
478 }
479
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500480 while (usb_trylock_device(udev) != 0) {
Alan Stern3ea15962005-08-11 10:15:39 -0400481
482 /* If we can't acquire the lock after waiting one second,
483 * we're probably deadlocked */
484 if (time_after(jiffies, jiffies_expire))
485 return -EBUSY;
486
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 msleep(15);
488 if (udev->state == USB_STATE_NOTATTACHED)
489 return -ENODEV;
490 if (udev->state == USB_STATE_SUSPENDED)
491 return -EHOSTUNREACH;
492 if (iface && iface->condition != USB_INTERFACE_BOUND)
493 return -EINTR;
494 }
495 return 1;
496}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600497EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498
499static struct usb_device *match_device(struct usb_device *dev,
500 u16 vendor_id, u16 product_id)
501{
502 struct usb_device *ret_dev = NULL;
503 int child;
504
505 dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
506 le16_to_cpu(dev->descriptor.idVendor),
507 le16_to_cpu(dev->descriptor.idProduct));
508
509 /* see if this device matches */
510 if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
511 (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
Oliver Neukum92516442007-01-23 15:55:28 -0500512 dev_dbg(&dev->dev, "matched this device!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 ret_dev = usb_get_dev(dev);
514 goto exit;
515 }
516
517 /* look through all of the children of this device */
518 for (child = 0; child < dev->maxchild; ++child) {
519 if (dev->children[child]) {
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500520 usb_lock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 ret_dev = match_device(dev->children[child],
522 vendor_id, product_id);
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500523 usb_unlock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 if (ret_dev)
525 goto exit;
526 }
527 }
528exit:
529 return ret_dev;
530}
531
532/**
533 * usb_find_device - find a specific usb device in the system
534 * @vendor_id: the vendor id of the device to find
535 * @product_id: the product id of the device to find
536 *
537 * Returns a pointer to a struct usb_device if such a specified usb
538 * device is present in the system currently. The usage count of the
539 * device will be incremented if a device is found. Make sure to call
540 * usb_put_dev() when the caller is finished with the device.
541 *
542 * If a device with the specified vendor and product id is not found,
543 * NULL is returned.
544 */
545struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
546{
547 struct list_head *buslist;
548 struct usb_bus *bus;
549 struct usb_device *dev = NULL;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800550
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100551 mutex_lock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 for (buslist = usb_bus_list.next;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800553 buslist != &usb_bus_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 buslist = buslist->next) {
555 bus = container_of(buslist, struct usb_bus, bus_list);
556 if (!bus->root_hub)
557 continue;
558 usb_lock_device(bus->root_hub);
559 dev = match_device(bus->root_hub, vendor_id, product_id);
560 usb_unlock_device(bus->root_hub);
561 if (dev)
562 goto exit;
563 }
564exit:
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100565 mutex_unlock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 return dev;
567}
568
569/**
570 * usb_get_current_frame_number - return current bus frame number
571 * @dev: the device whose bus is being queried
572 *
573 * Returns the current frame number for the USB host controller
574 * used with the given USB device. This can be used when scheduling
575 * isochronous requests.
576 *
577 * Note that different kinds of host controller have different
578 * "scheduling horizons". While one type might support scheduling only
579 * 32 frames into the future, others could support scheduling up to
580 * 1024 frames into the future.
581 */
582int usb_get_current_frame_number(struct usb_device *dev)
583{
Oliver Neukum92516442007-01-23 15:55:28 -0500584 return usb_hcd_get_frame_number(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600586EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
588/*-------------------------------------------------------------------*/
589/*
590 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
591 * extra field of the interface and endpoint descriptor structs.
592 */
593
594int __usb_get_extra_descriptor(char *buffer, unsigned size,
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800595 unsigned char type, void **ptr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596{
597 struct usb_descriptor_header *header;
598
599 while (size >= sizeof(struct usb_descriptor_header)) {
600 header = (struct usb_descriptor_header *)buffer;
601
602 if (header->bLength < 2) {
603 printk(KERN_ERR
604 "%s: bogus descriptor, type %d length %d\n",
605 usbcore_name,
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800606 header->bDescriptorType,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 header->bLength);
608 return -1;
609 }
610
611 if (header->bDescriptorType == type) {
612 *ptr = header;
613 return 0;
614 }
615
616 buffer += header->bLength;
617 size -= header->bLength;
618 }
619 return -1;
620}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600621EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622
623/**
624 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
625 * @dev: device the buffer will be used with
626 * @size: requested buffer size
627 * @mem_flags: affect whether allocation may block
628 * @dma: used to return DMA address of buffer
629 *
630 * Return value is either null (indicating no buffer could be allocated), or
631 * the cpu-space pointer to a buffer that may be used to perform DMA to the
632 * specified device. Such cpu-space buffers are returned along with the DMA
633 * address (through the pointer provided).
634 *
635 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
David Brownellfbf54dd2007-07-01 23:33:12 -0700636 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
637 * hardware during URB completion/resubmit. The implementation varies between
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 * platforms, depending on details of how DMA will work to this device.
David Brownellfbf54dd2007-07-01 23:33:12 -0700639 * Using these buffers also eliminates cacheline sharing problems on
640 * architectures where CPU caches are not DMA-coherent. On systems without
641 * bus-snooping caches, these buffers are uncached.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 *
643 * When the buffer is no longer used, free it with usb_buffer_free().
644 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800645void *usb_buffer_alloc(struct usb_device *dev, size_t size, gfp_t mem_flags,
646 dma_addr_t *dma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400648 if (!dev || !dev->bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649 return NULL;
Oliver Neukum92516442007-01-23 15:55:28 -0500650 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600652EXPORT_SYMBOL_GPL(usb_buffer_alloc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653
654/**
655 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
656 * @dev: device the buffer was used with
657 * @size: requested buffer size
658 * @addr: CPU address of buffer
659 * @dma: DMA address of buffer
660 *
661 * This reclaims an I/O buffer, letting it be reused. The memory must have
662 * been allocated using usb_buffer_alloc(), and the parameters must match
David Brownellfbf54dd2007-07-01 23:33:12 -0700663 * those provided in that allocation request.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800665void usb_buffer_free(struct usb_device *dev, size_t size, void *addr,
666 dma_addr_t dma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400668 if (!dev || !dev->bus)
Dmitry Torokhovb94badb2006-08-01 22:33:34 -0400669 return;
670 if (!addr)
671 return;
Oliver Neukum92516442007-01-23 15:55:28 -0500672 hcd_buffer_free(dev->bus, size, addr, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600674EXPORT_SYMBOL_GPL(usb_buffer_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675
676/**
677 * usb_buffer_map - create DMA mapping(s) for an urb
678 * @urb: urb whose transfer_buffer/setup_packet will be mapped
679 *
680 * Return value is either null (indicating no buffer could be mapped), or
681 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
682 * added to urb->transfer_flags if the operation succeeds. If the device
683 * is connected to this system through a non-DMA controller, this operation
684 * always succeeds.
685 *
686 * This call would normally be used for an urb which is reused, perhaps
687 * as the target of a large periodic transfer, with usb_buffer_dmasync()
688 * calls to synchronize memory and dma state.
689 *
690 * Reverse the effect of this call with usb_buffer_unmap().
691 */
692#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500693struct urb *usb_buffer_map(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694{
695 struct usb_bus *bus;
696 struct device *controller;
697
698 if (!urb
699 || !urb->dev
700 || !(bus = urb->dev->bus)
701 || !(controller = bus->controller))
702 return NULL;
703
704 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500705 urb->transfer_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 urb->transfer_buffer, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500707 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500709 if (usb_pipecontrol(urb->pipe))
710 urb->setup_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 urb->setup_packet,
Oliver Neukum92516442007-01-23 15:55:28 -0500712 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 DMA_TO_DEVICE);
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800714 /* FIXME generic api broken like pci, can't report errors */
715 /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 } else
717 urb->transfer_dma = ~0;
718 urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
719 | URB_NO_SETUP_DMA_MAP);
720 return urb;
721}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600722EXPORT_SYMBOL_GPL(usb_buffer_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723#endif /* 0 */
724
725/* XXX DISABLED, no users currently. If you wish to re-enable this
726 * XXX please determine whether the sync is to transfer ownership of
727 * XXX the buffer from device to cpu or vice verse, and thusly use the
728 * XXX appropriate _for_{cpu,device}() method. -DaveM
729 */
730#if 0
731
732/**
733 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
734 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
735 */
Oliver Neukum92516442007-01-23 15:55:28 -0500736void usb_buffer_dmasync(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737{
738 struct usb_bus *bus;
739 struct device *controller;
740
741 if (!urb
742 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
743 || !urb->dev
744 || !(bus = urb->dev->bus)
745 || !(controller = bus->controller))
746 return;
747
748 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500749 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500751 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500753 if (usb_pipecontrol(urb->pipe))
754 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500756 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 DMA_TO_DEVICE);
758 }
759}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600760EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761#endif
762
763/**
764 * usb_buffer_unmap - free DMA mapping(s) for an urb
765 * @urb: urb whose transfer_buffer will be unmapped
766 *
767 * Reverses the effect of usb_buffer_map().
768 */
769#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500770void usb_buffer_unmap(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771{
772 struct usb_bus *bus;
773 struct device *controller;
774
775 if (!urb
776 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
777 || !urb->dev
778 || !(bus = urb->dev->bus)
779 || !(controller = bus->controller))
780 return;
781
782 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500783 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500785 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500787 if (usb_pipecontrol(urb->pipe))
788 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500790 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 DMA_TO_DEVICE);
792 }
793 urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
794 | URB_NO_SETUP_DMA_MAP);
795}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600796EXPORT_SYMBOL_GPL(usb_buffer_unmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797#endif /* 0 */
798
799/**
800 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
801 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400802 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 * @sg: the scatterlist to map
804 * @nents: the number of entries in the scatterlist
805 *
806 * Return value is either < 0 (indicating no buffers could be mapped), or
807 * the number of DMA mapping array entries in the scatterlist.
808 *
809 * The caller is responsible for placing the resulting DMA addresses from
810 * the scatterlist into URB transfer buffer pointers, and for setting the
811 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
812 *
813 * Top I/O rates come from queuing URBs, instead of waiting for each one
814 * to complete before starting the next I/O. This is particularly easy
815 * to do with scatterlists. Just allocate and submit one URB for each DMA
816 * mapping entry returned, stopping on the first error or when all succeed.
817 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
818 *
819 * This call would normally be used when translating scatterlist requests,
820 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
821 * may be able to coalesce mappings for improved I/O efficiency.
822 *
823 * Reverse the effect of this call with usb_buffer_unmap_sg().
824 */
Alan Stern5e60a162007-07-30 17:07:21 -0400825int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300826 struct scatterlist *sg, int nents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827{
828 struct usb_bus *bus;
829 struct device *controller;
830
831 if (!dev
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832 || !(bus = dev->bus)
833 || !(controller = bus->controller)
834 || !controller->dma_mask)
835 return -1;
836
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800837 /* FIXME generic api broken like pci, can't report errors */
Oliver Neukum92516442007-01-23 15:55:28 -0500838 return dma_map_sg(controller, sg, nents,
Alan Stern5e60a162007-07-30 17:07:21 -0400839 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600841EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842
843/* XXX DISABLED, no users currently. If you wish to re-enable this
844 * XXX please determine whether the sync is to transfer ownership of
845 * XXX the buffer from device to cpu or vice verse, and thusly use the
846 * XXX appropriate _for_{cpu,device}() method. -DaveM
847 */
848#if 0
849
850/**
851 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
852 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400853 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 * @sg: the scatterlist to synchronize
855 * @n_hw_ents: the positive return value from usb_buffer_map_sg
856 *
857 * Use this when you are re-using a scatterlist's data buffers for
858 * another USB request.
859 */
Alan Stern5e60a162007-07-30 17:07:21 -0400860void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300861 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862{
863 struct usb_bus *bus;
864 struct device *controller;
865
866 if (!dev
867 || !(bus = dev->bus)
868 || !(controller = bus->controller)
869 || !controller->dma_mask)
870 return;
871
Oliver Neukum92516442007-01-23 15:55:28 -0500872 dma_sync_sg(controller, sg, n_hw_ents,
Alan Stern5e60a162007-07-30 17:07:21 -0400873 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600875EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876#endif
877
878/**
879 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
880 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400881 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 * @sg: the scatterlist to unmap
883 * @n_hw_ents: the positive return value from usb_buffer_map_sg
884 *
885 * Reverses the effect of usb_buffer_map_sg().
886 */
Alan Stern5e60a162007-07-30 17:07:21 -0400887void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300888 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889{
890 struct usb_bus *bus;
891 struct device *controller;
892
893 if (!dev
894 || !(bus = dev->bus)
895 || !(controller = bus->controller)
896 || !controller->dma_mask)
897 return;
898
Oliver Neukum92516442007-01-23 15:55:28 -0500899 dma_unmap_sg(controller, sg, n_hw_ents,
Alan Stern5e60a162007-07-30 17:07:21 -0400900 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600902EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904/* format to disable USB on kernel command line is: nousb */
Pete Zaitcevaafbf242005-12-20 14:15:04 -0800905__module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906
907/*
908 * for external read access to <nousb>
909 */
910int usb_disabled(void)
911{
912 return nousb;
913}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600914EXPORT_SYMBOL_GPL(usb_disabled);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915
916/*
917 * Init
918 */
919static int __init usb_init(void)
920{
921 int retval;
922 if (nousb) {
Oliver Neukum92516442007-01-23 15:55:28 -0500923 pr_info("%s: USB support disabled\n", usbcore_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 return 0;
925 }
926
Alan Sternbd859282006-09-19 10:14:07 -0400927 retval = ksuspend_usb_init();
928 if (retval)
929 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 retval = bus_register(&usb_bus_type);
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800931 if (retval)
Alan Sternbd859282006-09-19 10:14:07 -0400932 goto bus_register_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 retval = usb_host_init();
934 if (retval)
935 goto host_init_failed;
936 retval = usb_major_init();
937 if (retval)
938 goto major_init_failed;
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200939 retval = usb_register(&usbfs_driver);
940 if (retval)
941 goto driver_register_failed;
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100942 retval = usb_devio_init();
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200943 if (retval)
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100944 goto usb_devio_init_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 retval = usbfs_init();
946 if (retval)
947 goto fs_init_failed;
948 retval = usb_hub_init();
949 if (retval)
950 goto hub_init_failed;
Alan Stern8bb54ab2006-07-01 22:08:49 -0400951 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952 if (!retval)
953 goto out;
954
955 usb_hub_cleanup();
956hub_init_failed:
957 usbfs_cleanup();
958fs_init_failed:
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100959 usb_devio_cleanup();
960usb_devio_init_failed:
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200961 usb_deregister(&usbfs_driver);
962driver_register_failed:
963 usb_major_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964major_init_failed:
965 usb_host_cleanup();
966host_init_failed:
967 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400968bus_register_failed:
969 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970out:
971 return retval;
972}
973
974/*
975 * Cleanup
976 */
977static void __exit usb_exit(void)
978{
979 /* This will matter if shutdown/reboot does exitcalls. */
980 if (nousb)
981 return;
982
Alan Stern8bb54ab2006-07-01 22:08:49 -0400983 usb_deregister_device_driver(&usb_generic_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984 usb_major_cleanup();
985 usbfs_cleanup();
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200986 usb_deregister(&usbfs_driver);
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100987 usb_devio_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988 usb_hub_cleanup();
989 usb_host_cleanup();
990 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400991 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992}
993
994subsys_initcall(usb_init);
995module_exit(usb_exit);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996MODULE_LICENSE("GPL");