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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * drivers/usb/core/usb.c
4 *
5 * (C) Copyright Linus Torvalds 1999
6 * (C) Copyright Johannes Erdfelt 1999-2001
7 * (C) Copyright Andreas Gal 1999
8 * (C) Copyright Gregory P. Smith 1999
9 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
10 * (C) Copyright Randy Dunlap 2000
11 * (C) Copyright David Brownell 2000-2004
12 * (C) Copyright Yggdrasil Computing, Inc. 2000
13 * (usb_device_id matching changes by Adam J. Richter)
14 * (C) Copyright Greg Kroah-Hartman 2002-2003
15 *
16 * Released under the GPLv2 only.
17 *
18 * NOTE! This is not actually a driver at all, rather this is
19 * just a collection of helper routines that implement the
20 * generic USB things that the real drivers can use..
21 *
22 * Think of this as a "USB library" rather than anything else,
23 * with no callbacks. Callbacks are evil.
24 */
25
26#include <linux/module.h>
27#include <linux/moduleparam.h>
28#include <linux/string.h>
29#include <linux/bitops.h>
30#include <linux/slab.h>
31#include <linux/kmod.h>
32#include <linux/init.h>
33#include <linux/spinlock.h>
34#include <linux/errno.h>
35#include <linux/usb.h>
36#include <linux/usb/hcd.h>
37#include <linux/mutex.h>
38#include <linux/workqueue.h>
39#include <linux/debugfs.h>
40#include <linux/usb/of.h>
41
42#include <asm/io.h>
43#include <linux/scatterlist.h>
44#include <linux/mm.h>
45#include <linux/dma-mapping.h>
46
47#include "hub.h"
48
49const char *usbcore_name = "usbcore";
50
51static bool nousb; /* Disable USB when built into kernel image */
52
53module_param(nousb, bool, 0444);
54
55/*
56 * for external read access to <nousb>
57 */
58int usb_disabled(void)
59{
60 return nousb;
61}
62EXPORT_SYMBOL_GPL(usb_disabled);
63
64#ifdef CONFIG_PM
65/* Default delay value, in seconds */
66static int usb_autosuspend_delay = CONFIG_USB_AUTOSUSPEND_DELAY;
67module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
68MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
69
70#else
71#define usb_autosuspend_delay 0
72#endif
73
74static bool match_endpoint(struct usb_endpoint_descriptor *epd,
75 struct usb_endpoint_descriptor **bulk_in,
76 struct usb_endpoint_descriptor **bulk_out,
77 struct usb_endpoint_descriptor **int_in,
78 struct usb_endpoint_descriptor **int_out)
79{
80 switch (usb_endpoint_type(epd)) {
81 case USB_ENDPOINT_XFER_BULK:
82 if (usb_endpoint_dir_in(epd)) {
83 if (bulk_in && !*bulk_in) {
84 *bulk_in = epd;
85 break;
86 }
87 } else {
88 if (bulk_out && !*bulk_out) {
89 *bulk_out = epd;
90 break;
91 }
92 }
93
94 return false;
95 case USB_ENDPOINT_XFER_INT:
96 if (usb_endpoint_dir_in(epd)) {
97 if (int_in && !*int_in) {
98 *int_in = epd;
99 break;
100 }
101 } else {
102 if (int_out && !*int_out) {
103 *int_out = epd;
104 break;
105 }
106 }
107
108 return false;
109 default:
110 return false;
111 }
112
113 return (!bulk_in || *bulk_in) && (!bulk_out || *bulk_out) &&
114 (!int_in || *int_in) && (!int_out || *int_out);
115}
116
117/**
118 * usb_find_common_endpoints() -- look up common endpoint descriptors
119 * @alt: alternate setting to search
120 * @bulk_in: pointer to descriptor pointer, or NULL
121 * @bulk_out: pointer to descriptor pointer, or NULL
122 * @int_in: pointer to descriptor pointer, or NULL
123 * @int_out: pointer to descriptor pointer, or NULL
124 *
125 * Search the alternate setting's endpoint descriptors for the first bulk-in,
126 * bulk-out, interrupt-in and interrupt-out endpoints and return them in the
127 * provided pointers (unless they are NULL).
128 *
129 * If a requested endpoint is not found, the corresponding pointer is set to
130 * NULL.
131 *
132 * Return: Zero if all requested descriptors were found, or -ENXIO otherwise.
133 */
134int usb_find_common_endpoints(struct usb_host_interface *alt,
135 struct usb_endpoint_descriptor **bulk_in,
136 struct usb_endpoint_descriptor **bulk_out,
137 struct usb_endpoint_descriptor **int_in,
138 struct usb_endpoint_descriptor **int_out)
139{
140 struct usb_endpoint_descriptor *epd;
141 int i;
142
143 if (bulk_in)
144 *bulk_in = NULL;
145 if (bulk_out)
146 *bulk_out = NULL;
147 if (int_in)
148 *int_in = NULL;
149 if (int_out)
150 *int_out = NULL;
151
152 for (i = 0; i < alt->desc.bNumEndpoints; ++i) {
153 epd = &alt->endpoint[i].desc;
154
155 if (match_endpoint(epd, bulk_in, bulk_out, int_in, int_out))
156 return 0;
157 }
158
159 return -ENXIO;
160}
161EXPORT_SYMBOL_GPL(usb_find_common_endpoints);
162
163/**
164 * usb_find_common_endpoints_reverse() -- look up common endpoint descriptors
165 * @alt: alternate setting to search
166 * @bulk_in: pointer to descriptor pointer, or NULL
167 * @bulk_out: pointer to descriptor pointer, or NULL
168 * @int_in: pointer to descriptor pointer, or NULL
169 * @int_out: pointer to descriptor pointer, or NULL
170 *
171 * Search the alternate setting's endpoint descriptors for the last bulk-in,
172 * bulk-out, interrupt-in and interrupt-out endpoints and return them in the
173 * provided pointers (unless they are NULL).
174 *
175 * If a requested endpoint is not found, the corresponding pointer is set to
176 * NULL.
177 *
178 * Return: Zero if all requested descriptors were found, or -ENXIO otherwise.
179 */
180int usb_find_common_endpoints_reverse(struct usb_host_interface *alt,
181 struct usb_endpoint_descriptor **bulk_in,
182 struct usb_endpoint_descriptor **bulk_out,
183 struct usb_endpoint_descriptor **int_in,
184 struct usb_endpoint_descriptor **int_out)
185{
186 struct usb_endpoint_descriptor *epd;
187 int i;
188
189 if (bulk_in)
190 *bulk_in = NULL;
191 if (bulk_out)
192 *bulk_out = NULL;
193 if (int_in)
194 *int_in = NULL;
195 if (int_out)
196 *int_out = NULL;
197
198 for (i = alt->desc.bNumEndpoints - 1; i >= 0; --i) {
199 epd = &alt->endpoint[i].desc;
200
201 if (match_endpoint(epd, bulk_in, bulk_out, int_in, int_out))
202 return 0;
203 }
204
205 return -ENXIO;
206}
207EXPORT_SYMBOL_GPL(usb_find_common_endpoints_reverse);
208
209/**
210 * usb_find_alt_setting() - Given a configuration, find the alternate setting
211 * for the given interface.
212 * @config: the configuration to search (not necessarily the current config).
213 * @iface_num: interface number to search in
214 * @alt_num: alternate interface setting number to search for.
215 *
216 * Search the configuration's interface cache for the given alt setting.
217 *
218 * Return: The alternate setting, if found. %NULL otherwise.
219 */
220struct usb_host_interface *usb_find_alt_setting(
221 struct usb_host_config *config,
222 unsigned int iface_num,
223 unsigned int alt_num)
224{
225 struct usb_interface_cache *intf_cache = NULL;
226 int i;
227
228 if (!config)
229 return NULL;
230 for (i = 0; i < config->desc.bNumInterfaces; i++) {
231 if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber
232 == iface_num) {
233 intf_cache = config->intf_cache[i];
234 break;
235 }
236 }
237 if (!intf_cache)
238 return NULL;
239 for (i = 0; i < intf_cache->num_altsetting; i++)
240 if (intf_cache->altsetting[i].desc.bAlternateSetting == alt_num)
241 return &intf_cache->altsetting[i];
242
243 printk(KERN_DEBUG "Did not find alt setting %u for intf %u, "
244 "config %u\n", alt_num, iface_num,
245 config->desc.bConfigurationValue);
246 return NULL;
247}
248EXPORT_SYMBOL_GPL(usb_find_alt_setting);
249
250/**
251 * usb_ifnum_to_if - get the interface object with a given interface number
252 * @dev: the device whose current configuration is considered
253 * @ifnum: the desired interface
254 *
255 * This walks the device descriptor for the currently active configuration
256 * to find the interface object with the particular interface number.
257 *
258 * Note that configuration descriptors are not required to assign interface
259 * numbers sequentially, so that it would be incorrect to assume that
260 * the first interface in that descriptor corresponds to interface zero.
261 * This routine helps device drivers avoid such mistakes.
262 * However, you should make sure that you do the right thing with any
263 * alternate settings available for this interfaces.
264 *
265 * Don't call this function unless you are bound to one of the interfaces
266 * on this device or you have locked the device!
267 *
268 * Return: A pointer to the interface that has @ifnum as interface number,
269 * if found. %NULL otherwise.
270 */
271struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
272 unsigned ifnum)
273{
274 struct usb_host_config *config = dev->actconfig;
275 int i;
276
277 if (!config)
278 return NULL;
279 for (i = 0; i < config->desc.bNumInterfaces; i++)
280 if (config->interface[i]->altsetting[0]
281 .desc.bInterfaceNumber == ifnum)
282 return config->interface[i];
283
284 return NULL;
285}
286EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
287
288/**
289 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
290 * @intf: the interface containing the altsetting in question
291 * @altnum: the desired alternate setting number
292 *
293 * This searches the altsetting array of the specified interface for
294 * an entry with the correct bAlternateSetting value.
295 *
296 * Note that altsettings need not be stored sequentially by number, so
297 * it would be incorrect to assume that the first altsetting entry in
298 * the array corresponds to altsetting zero. This routine helps device
299 * drivers avoid such mistakes.
300 *
301 * Don't call this function unless you are bound to the intf interface
302 * or you have locked the device!
303 *
304 * Return: A pointer to the entry of the altsetting array of @intf that
305 * has @altnum as the alternate setting number. %NULL if not found.
306 */
307struct usb_host_interface *usb_altnum_to_altsetting(
308 const struct usb_interface *intf,
309 unsigned int altnum)
310{
311 int i;
312
313 for (i = 0; i < intf->num_altsetting; i++) {
314 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
315 return &intf->altsetting[i];
316 }
317 return NULL;
318}
319EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
320
321struct find_interface_arg {
322 int minor;
323 struct device_driver *drv;
324};
325
326static int __find_interface(struct device *dev, const void *data)
327{
328 const struct find_interface_arg *arg = data;
329 struct usb_interface *intf;
330
331 if (!is_usb_interface(dev))
332 return 0;
333
334 if (dev->driver != arg->drv)
335 return 0;
336 intf = to_usb_interface(dev);
337 return intf->minor == arg->minor;
338}
339
340/**
341 * usb_find_interface - find usb_interface pointer for driver and device
342 * @drv: the driver whose current configuration is considered
343 * @minor: the minor number of the desired device
344 *
345 * This walks the bus device list and returns a pointer to the interface
346 * with the matching minor and driver. Note, this only works for devices
347 * that share the USB major number.
348 *
349 * Return: A pointer to the interface with the matching major and @minor.
350 */
351struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
352{
353 struct find_interface_arg argb;
354 struct device *dev;
355
356 argb.minor = minor;
357 argb.drv = &drv->drvwrap.driver;
358
359 dev = bus_find_device(&usb_bus_type, NULL, &argb, __find_interface);
360
361 /* Drop reference count from bus_find_device */
362 put_device(dev);
363
364 return dev ? to_usb_interface(dev) : NULL;
365}
366EXPORT_SYMBOL_GPL(usb_find_interface);
367
368struct each_dev_arg {
369 void *data;
370 int (*fn)(struct usb_device *, void *);
371};
372
373static int __each_dev(struct device *dev, void *data)
374{
375 struct each_dev_arg *arg = (struct each_dev_arg *)data;
376
377 /* There are struct usb_interface on the same bus, filter them out */
378 if (!is_usb_device(dev))
379 return 0;
380
381 return arg->fn(to_usb_device(dev), arg->data);
382}
383
384/**
385 * usb_for_each_dev - iterate over all USB devices in the system
386 * @data: data pointer that will be handed to the callback function
387 * @fn: callback function to be called for each USB device
388 *
389 * Iterate over all USB devices and call @fn for each, passing it @data. If it
390 * returns anything other than 0, we break the iteration prematurely and return
391 * that value.
392 */
393int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *))
394{
395 struct each_dev_arg arg = {data, fn};
396
397 return bus_for_each_dev(&usb_bus_type, NULL, &arg, __each_dev);
398}
399EXPORT_SYMBOL_GPL(usb_for_each_dev);
400
401/**
402 * usb_release_dev - free a usb device structure when all users of it are finished.
403 * @dev: device that's been disconnected
404 *
405 * Will be called only by the device core when all users of this usb device are
406 * done.
407 */
408static void usb_release_dev(struct device *dev)
409{
410 struct usb_device *udev;
411 struct usb_hcd *hcd;
412
413 udev = to_usb_device(dev);
414 hcd = bus_to_hcd(udev->bus);
415
416 usb_destroy_configuration(udev);
417 usb_release_bos_descriptor(udev);
418 of_node_put(dev->of_node);
419 usb_put_hcd(hcd);
420 kfree(udev->product);
421 kfree(udev->manufacturer);
422 kfree(udev->serial);
423 kfree(udev);
424}
425
426static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
427{
428 struct usb_device *usb_dev;
429
430 usb_dev = to_usb_device(dev);
431
432 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
433 return -ENOMEM;
434
435 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
436 return -ENOMEM;
437
438 return 0;
439}
440
441#ifdef CONFIG_PM
442
443/* USB device Power-Management thunks.
444 * There's no need to distinguish here between quiescing a USB device
445 * and powering it down; the generic_suspend() routine takes care of
446 * it by skipping the usb_port_suspend() call for a quiesce. And for
447 * USB interfaces there's no difference at all.
448 */
449
450static int usb_dev_prepare(struct device *dev)
451{
452 return 0; /* Implement eventually? */
453}
454
455static void usb_dev_complete(struct device *dev)
456{
457 /* Currently used only for rebinding interfaces */
458 usb_resume_complete(dev);
459}
460
461static int usb_dev_suspend(struct device *dev)
462{
463 return usb_suspend(dev, PMSG_SUSPEND);
464}
465
466static int usb_dev_resume(struct device *dev)
467{
468 return usb_resume(dev, PMSG_RESUME);
469}
470
471static int usb_dev_freeze(struct device *dev)
472{
473 return usb_suspend(dev, PMSG_FREEZE);
474}
475
476static int usb_dev_thaw(struct device *dev)
477{
478 return usb_resume(dev, PMSG_THAW);
479}
480
481static int usb_dev_poweroff(struct device *dev)
482{
483 return usb_suspend(dev, PMSG_HIBERNATE);
484}
485
486static int usb_dev_restore(struct device *dev)
487{
488 return usb_resume(dev, PMSG_RESTORE);
489}
490
491static const struct dev_pm_ops usb_device_pm_ops = {
492 .prepare = usb_dev_prepare,
493 .complete = usb_dev_complete,
494 .suspend = usb_dev_suspend,
495 .resume = usb_dev_resume,
496 .freeze = usb_dev_freeze,
497 .thaw = usb_dev_thaw,
498 .poweroff = usb_dev_poweroff,
499 .restore = usb_dev_restore,
500 .runtime_suspend = usb_runtime_suspend,
501 .runtime_resume = usb_runtime_resume,
502 .runtime_idle = usb_runtime_idle,
503};
504
505#endif /* CONFIG_PM */
506
507
508static char *usb_devnode(struct device *dev,
509 umode_t *mode, kuid_t *uid, kgid_t *gid)
510{
511 struct usb_device *usb_dev;
512
513 usb_dev = to_usb_device(dev);
514 return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
515 usb_dev->bus->busnum, usb_dev->devnum);
516}
517
518struct device_type usb_device_type = {
519 .name = "usb_device",
520 .release = usb_release_dev,
521 .uevent = usb_dev_uevent,
522 .devnode = usb_devnode,
523#ifdef CONFIG_PM
524 .pm = &usb_device_pm_ops,
525#endif
526};
527
528
529/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
530static unsigned usb_bus_is_wusb(struct usb_bus *bus)
531{
532 struct usb_hcd *hcd = bus_to_hcd(bus);
533 return hcd->wireless;
534}
535
536static bool usb_dev_authorized(struct usb_device *dev, struct usb_hcd *hcd)
537{
538 struct usb_hub *hub;
539
540 if (!dev->parent)
541 return true; /* Root hub always ok [and always wired] */
542
543 switch (hcd->dev_policy) {
544 case USB_DEVICE_AUTHORIZE_NONE:
545 default:
546 return false;
547
548 case USB_DEVICE_AUTHORIZE_ALL:
549 return true;
550
551 case USB_DEVICE_AUTHORIZE_INTERNAL:
552 hub = usb_hub_to_struct_hub(dev->parent);
553 return hub->ports[dev->portnum - 1]->connect_type ==
554 USB_PORT_CONNECT_TYPE_HARD_WIRED;
555 }
556}
557
558/**
559 * usb_alloc_dev - usb device constructor (usbcore-internal)
560 * @parent: hub to which device is connected; null to allocate a root hub
561 * @bus: bus used to access the device
562 * @port1: one-based index of port; ignored for root hubs
563 *
564 * Context: task context, might sleep.
565 *
566 * Only hub drivers (including virtual root hub drivers for host
567 * controllers) should ever call this.
568 *
569 * This call may not be used in a non-sleeping context.
570 *
571 * Return: On success, a pointer to the allocated usb device. %NULL on
572 * failure.
573 */
574struct usb_device *usb_alloc_dev(struct usb_device *parent,
575 struct usb_bus *bus, unsigned port1)
576{
577 struct usb_device *dev;
578 struct usb_hcd *usb_hcd = bus_to_hcd(bus);
579 unsigned root_hub = 0;
580 unsigned raw_port = port1;
581
582 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
583 if (!dev)
584 return NULL;
585
586 if (!usb_get_hcd(usb_hcd)) {
587 kfree(dev);
588 return NULL;
589 }
590 /* Root hubs aren't true devices, so don't allocate HCD resources */
591 if (usb_hcd->driver->alloc_dev && parent &&
592 !usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
593 usb_put_hcd(bus_to_hcd(bus));
594 kfree(dev);
595 return NULL;
596 }
597
598 device_initialize(&dev->dev);
599 dev->dev.bus = &usb_bus_type;
600 dev->dev.type = &usb_device_type;
601 dev->dev.groups = usb_device_groups;
602 set_dev_node(&dev->dev, dev_to_node(bus->sysdev));
603 dev->state = USB_STATE_ATTACHED;
604 dev->lpm_disable_count = 1;
605 atomic_set(&dev->urbnum, 0);
606
607 INIT_LIST_HEAD(&dev->ep0.urb_list);
608 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
609 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
610 /* ep0 maxpacket comes later, from device descriptor */
611 usb_enable_endpoint(dev, &dev->ep0, false);
612 dev->can_submit = 1;
613
614 /* Save readable and stable topology id, distinguishing devices
615 * by location for diagnostics, tools, driver model, etc. The
616 * string is a path along hub ports, from the root. Each device's
617 * dev->devpath will be stable until USB is re-cabled, and hubs
618 * are often labeled with these port numbers. The name isn't
619 * as stable: bus->busnum changes easily from modprobe order,
620 * cardbus or pci hotplugging, and so on.
621 */
622 if (unlikely(!parent)) {
623 dev->devpath[0] = '0';
624 dev->route = 0;
625
626 dev->dev.parent = bus->controller;
627 device_set_of_node_from_dev(&dev->dev, bus->sysdev);
628 dev_set_name(&dev->dev, "usb%d", bus->busnum);
629 root_hub = 1;
630 } else {
631 /* match any labeling on the hubs; it's one-based */
632 if (parent->devpath[0] == '0') {
633 snprintf(dev->devpath, sizeof dev->devpath,
634 "%d", port1);
635 /* Root ports are not counted in route string */
636 dev->route = 0;
637 } else {
638 snprintf(dev->devpath, sizeof dev->devpath,
639 "%s.%d", parent->devpath, port1);
640 /* Route string assumes hubs have less than 16 ports */
641 if (port1 < 15)
642 dev->route = parent->route +
643 (port1 << ((parent->level - 1)*4));
644 else
645 dev->route = parent->route +
646 (15 << ((parent->level - 1)*4));
647 }
648
649 dev->dev.parent = &parent->dev;
650 dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
651
652 if (!parent->parent) {
653 /* device under root hub's port */
654 raw_port = usb_hcd_find_raw_port_number(usb_hcd,
655 port1);
656 }
657 dev->dev.of_node = usb_of_get_device_node(parent, raw_port);
658
659 /* hub driver sets up TT records */
660 }
661
662 dev->portnum = port1;
663 dev->bus = bus;
664 dev->parent = parent;
665 INIT_LIST_HEAD(&dev->filelist);
666
667#ifdef CONFIG_PM
668 pm_runtime_set_autosuspend_delay(&dev->dev,
669 usb_autosuspend_delay * 1000);
670 dev->connect_time = jiffies;
671 dev->active_duration = -jiffies;
672#endif
673
674 dev->authorized = usb_dev_authorized(dev, usb_hcd);
675 if (!root_hub)
676 dev->wusb = usb_bus_is_wusb(bus) ? 1 : 0;
677
678 return dev;
679}
680EXPORT_SYMBOL_GPL(usb_alloc_dev);
681
682/**
683 * usb_get_dev - increments the reference count of the usb device structure
684 * @dev: the device being referenced
685 *
686 * Each live reference to a device should be refcounted.
687 *
688 * Drivers for USB interfaces should normally record such references in
689 * their probe() methods, when they bind to an interface, and release
690 * them by calling usb_put_dev(), in their disconnect() methods.
691 * However, if a driver does not access the usb_device structure after
692 * its disconnect() method returns then refcounting is not necessary,
693 * because the USB core guarantees that a usb_device will not be
694 * deallocated until after all of its interface drivers have been unbound.
695 *
696 * Return: A pointer to the device with the incremented reference counter.
697 */
698struct usb_device *usb_get_dev(struct usb_device *dev)
699{
700 if (dev)
701 get_device(&dev->dev);
702 return dev;
703}
704EXPORT_SYMBOL_GPL(usb_get_dev);
705
706/**
707 * usb_put_dev - release a use of the usb device structure
708 * @dev: device that's been disconnected
709 *
710 * Must be called when a user of a device is finished with it. When the last
711 * user of the device calls this function, the memory of the device is freed.
712 */
713void usb_put_dev(struct usb_device *dev)
714{
715 if (dev)
716 put_device(&dev->dev);
717}
718EXPORT_SYMBOL_GPL(usb_put_dev);
719
720/**
721 * usb_get_intf - increments the reference count of the usb interface structure
722 * @intf: the interface being referenced
723 *
724 * Each live reference to a interface must be refcounted.
725 *
726 * Drivers for USB interfaces should normally record such references in
727 * their probe() methods, when they bind to an interface, and release
728 * them by calling usb_put_intf(), in their disconnect() methods.
729 * However, if a driver does not access the usb_interface structure after
730 * its disconnect() method returns then refcounting is not necessary,
731 * because the USB core guarantees that a usb_interface will not be
732 * deallocated until after its driver has been unbound.
733 *
734 * Return: A pointer to the interface with the incremented reference counter.
735 */
736struct usb_interface *usb_get_intf(struct usb_interface *intf)
737{
738 if (intf)
739 get_device(&intf->dev);
740 return intf;
741}
742EXPORT_SYMBOL_GPL(usb_get_intf);
743
744/**
745 * usb_put_intf - release a use of the usb interface structure
746 * @intf: interface that's been decremented
747 *
748 * Must be called when a user of an interface is finished with it. When the
749 * last user of the interface calls this function, the memory of the interface
750 * is freed.
751 */
752void usb_put_intf(struct usb_interface *intf)
753{
754 if (intf)
755 put_device(&intf->dev);
756}
757EXPORT_SYMBOL_GPL(usb_put_intf);
758
759/**
760 * usb_intf_get_dma_device - acquire a reference on the usb interface's DMA endpoint
761 * @intf: the usb interface
762 *
763 * While a USB device cannot perform DMA operations by itself, many USB
764 * controllers can. A call to usb_intf_get_dma_device() returns the DMA endpoint
765 * for the given USB interface, if any. The returned device structure must be
766 * released with put_device().
767 *
768 * See also usb_get_dma_device().
769 *
770 * Returns: A reference to the usb interface's DMA endpoint; or NULL if none
771 * exists.
772 */
773struct device *usb_intf_get_dma_device(struct usb_interface *intf)
774{
775 struct usb_device *udev = interface_to_usbdev(intf);
776 struct device *dmadev;
777
778 if (!udev->bus)
779 return NULL;
780
781 dmadev = get_device(udev->bus->sysdev);
782 if (!dmadev || !dmadev->dma_mask) {
783 put_device(dmadev);
784 return NULL;
785 }
786
787 return dmadev;
788}
789EXPORT_SYMBOL_GPL(usb_intf_get_dma_device);
790
791/* USB device locking
792 *
793 * USB devices and interfaces are locked using the semaphore in their
794 * embedded struct device. The hub driver guarantees that whenever a
795 * device is connected or disconnected, drivers are called with the
796 * USB device locked as well as their particular interface.
797 *
798 * Complications arise when several devices are to be locked at the same
799 * time. Only hub-aware drivers that are part of usbcore ever have to
800 * do this; nobody else needs to worry about it. The rule for locking
801 * is simple:
802 *
803 * When locking both a device and its parent, always lock the
804 * parent first.
805 */
806
807/**
808 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
809 * @udev: device that's being locked
810 * @iface: interface bound to the driver making the request (optional)
811 *
812 * Attempts to acquire the device lock, but fails if the device is
813 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
814 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
815 * lock, the routine polls repeatedly. This is to prevent deadlock with
816 * disconnect; in some drivers (such as usb-storage) the disconnect()
817 * or suspend() method will block waiting for a device reset to complete.
818 *
819 * Return: A negative error code for failure, otherwise 0.
820 */
821int usb_lock_device_for_reset(struct usb_device *udev,
822 const struct usb_interface *iface)
823{
824 unsigned long jiffies_expire = jiffies + HZ;
825
826 if (udev->state == USB_STATE_NOTATTACHED)
827 return -ENODEV;
828 if (udev->state == USB_STATE_SUSPENDED)
829 return -EHOSTUNREACH;
830 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
831 iface->condition == USB_INTERFACE_UNBOUND))
832 return -EINTR;
833
834 while (!usb_trylock_device(udev)) {
835
836 /* If we can't acquire the lock after waiting one second,
837 * we're probably deadlocked */
838 if (time_after(jiffies, jiffies_expire))
839 return -EBUSY;
840
841 msleep(15);
842 if (udev->state == USB_STATE_NOTATTACHED)
843 return -ENODEV;
844 if (udev->state == USB_STATE_SUSPENDED)
845 return -EHOSTUNREACH;
846 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
847 iface->condition == USB_INTERFACE_UNBOUND))
848 return -EINTR;
849 }
850 return 0;
851}
852EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
853
854/**
855 * usb_get_current_frame_number - return current bus frame number
856 * @dev: the device whose bus is being queried
857 *
858 * Return: The current frame number for the USB host controller used
859 * with the given USB device. This can be used when scheduling
860 * isochronous requests.
861 *
862 * Note: Different kinds of host controller have different "scheduling
863 * horizons". While one type might support scheduling only 32 frames
864 * into the future, others could support scheduling up to 1024 frames
865 * into the future.
866 *
867 */
868int usb_get_current_frame_number(struct usb_device *dev)
869{
870 return usb_hcd_get_frame_number(dev);
871}
872EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
873
874/*-------------------------------------------------------------------*/
875/*
876 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
877 * extra field of the interface and endpoint descriptor structs.
878 */
879
880int __usb_get_extra_descriptor(char *buffer, unsigned size,
881 unsigned char type, void **ptr, size_t minsize)
882{
883 struct usb_descriptor_header *header;
884
885 while (size >= sizeof(struct usb_descriptor_header)) {
886 header = (struct usb_descriptor_header *)buffer;
887
888 if (header->bLength < 2 || header->bLength > size) {
889 printk(KERN_ERR
890 "%s: bogus descriptor, type %d length %d\n",
891 usbcore_name,
892 header->bDescriptorType,
893 header->bLength);
894 return -1;
895 }
896
897 if (header->bDescriptorType == type && header->bLength >= minsize) {
898 *ptr = header;
899 return 0;
900 }
901
902 buffer += header->bLength;
903 size -= header->bLength;
904 }
905 return -1;
906}
907EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
908
909/**
910 * usb_alloc_coherent - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
911 * @dev: device the buffer will be used with
912 * @size: requested buffer size
913 * @mem_flags: affect whether allocation may block
914 * @dma: used to return DMA address of buffer
915 *
916 * Return: Either null (indicating no buffer could be allocated), or the
917 * cpu-space pointer to a buffer that may be used to perform DMA to the
918 * specified device. Such cpu-space buffers are returned along with the DMA
919 * address (through the pointer provided).
920 *
921 * Note:
922 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
923 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
924 * hardware during URB completion/resubmit. The implementation varies between
925 * platforms, depending on details of how DMA will work to this device.
926 * Using these buffers also eliminates cacheline sharing problems on
927 * architectures where CPU caches are not DMA-coherent. On systems without
928 * bus-snooping caches, these buffers are uncached.
929 *
930 * When the buffer is no longer used, free it with usb_free_coherent().
931 */
932void *usb_alloc_coherent(struct usb_device *dev, size_t size, gfp_t mem_flags,
933 dma_addr_t *dma)
934{
935 if (!dev || !dev->bus)
936 return NULL;
937 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
938}
939EXPORT_SYMBOL_GPL(usb_alloc_coherent);
940
941/**
942 * usb_free_coherent - free memory allocated with usb_alloc_coherent()
943 * @dev: device the buffer was used with
944 * @size: requested buffer size
945 * @addr: CPU address of buffer
946 * @dma: DMA address of buffer
947 *
948 * This reclaims an I/O buffer, letting it be reused. The memory must have
949 * been allocated using usb_alloc_coherent(), and the parameters must match
950 * those provided in that allocation request.
951 */
952void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
953 dma_addr_t dma)
954{
955 if (!dev || !dev->bus)
956 return;
957 if (!addr)
958 return;
959 hcd_buffer_free(dev->bus, size, addr, dma);
960}
961EXPORT_SYMBOL_GPL(usb_free_coherent);
962
963/*
964 * Notifications of device and interface registration
965 */
966static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
967 void *data)
968{
969 struct device *dev = data;
970
971 switch (action) {
972 case BUS_NOTIFY_ADD_DEVICE:
973 if (dev->type == &usb_device_type)
974 (void) usb_create_sysfs_dev_files(to_usb_device(dev));
975 else if (dev->type == &usb_if_device_type)
976 usb_create_sysfs_intf_files(to_usb_interface(dev));
977 break;
978
979 case BUS_NOTIFY_DEL_DEVICE:
980 if (dev->type == &usb_device_type)
981 usb_remove_sysfs_dev_files(to_usb_device(dev));
982 else if (dev->type == &usb_if_device_type)
983 usb_remove_sysfs_intf_files(to_usb_interface(dev));
984 break;
985 }
986 return 0;
987}
988
989static struct notifier_block usb_bus_nb = {
990 .notifier_call = usb_bus_notify,
991};
992
993static void usb_debugfs_init(void)
994{
995 debugfs_create_file("devices", 0444, usb_debug_root, NULL,
996 &usbfs_devices_fops);
997}
998
999static void usb_debugfs_cleanup(void)
1000{
1001 debugfs_remove(debugfs_lookup("devices", usb_debug_root));
1002}
1003
1004/*
1005 * Init
1006 */
1007static int __init usb_init(void)
1008{
1009 int retval;
1010 if (usb_disabled()) {
1011 pr_info("%s: USB support disabled\n", usbcore_name);
1012 return 0;
1013 }
1014 usb_init_pool_max();
1015
1016 usb_debugfs_init();
1017
1018 usb_acpi_register();
1019 retval = bus_register(&usb_bus_type);
1020 if (retval)
1021 goto bus_register_failed;
1022 retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
1023 if (retval)
1024 goto bus_notifier_failed;
1025 retval = usb_major_init();
1026 if (retval)
1027 goto major_init_failed;
1028 retval = usb_register(&usbfs_driver);
1029 if (retval)
1030 goto driver_register_failed;
1031 retval = usb_devio_init();
1032 if (retval)
1033 goto usb_devio_init_failed;
1034 retval = usb_hub_init();
1035 if (retval)
1036 goto hub_init_failed;
1037 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
1038 if (!retval)
1039 goto out;
1040
1041 usb_hub_cleanup();
1042hub_init_failed:
1043 usb_devio_cleanup();
1044usb_devio_init_failed:
1045 usb_deregister(&usbfs_driver);
1046driver_register_failed:
1047 usb_major_cleanup();
1048major_init_failed:
1049 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1050bus_notifier_failed:
1051 bus_unregister(&usb_bus_type);
1052bus_register_failed:
1053 usb_acpi_unregister();
1054 usb_debugfs_cleanup();
1055out:
1056 return retval;
1057}
1058
1059/*
1060 * Cleanup
1061 */
1062static void __exit usb_exit(void)
1063{
1064 /* This will matter if shutdown/reboot does exitcalls. */
1065 if (usb_disabled())
1066 return;
1067
1068 usb_release_quirk_list();
1069 usb_deregister_device_driver(&usb_generic_driver);
1070 usb_major_cleanup();
1071 usb_deregister(&usbfs_driver);
1072 usb_devio_cleanup();
1073 usb_hub_cleanup();
1074 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1075 bus_unregister(&usb_bus_type);
1076 usb_acpi_unregister();
1077 usb_debugfs_cleanup();
1078 idr_destroy(&usb_bus_idr);
1079}
1080
1081subsys_initcall(usb_init);
1082module_exit(usb_exit);
1083MODULE_LICENSE("GPL");
1/*
2 * drivers/usb/core/usb.c
3 *
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
24#include <linux/module.h>
25#include <linux/moduleparam.h>
26#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>
34#include <linux/usb.h>
35#include <linux/usb/hcd.h>
36#include <linux/mutex.h>
37#include <linux/workqueue.h>
38#include <linux/debugfs.h>
39
40#include <asm/io.h>
41#include <linux/scatterlist.h>
42#include <linux/mm.h>
43#include <linux/dma-mapping.h>
44
45#include "usb.h"
46
47
48const char *usbcore_name = "usbcore";
49
50static bool nousb; /* Disable USB when built into kernel image */
51
52#ifdef CONFIG_PM_RUNTIME
53static int usb_autosuspend_delay = 2; /* Default delay value,
54 * in seconds */
55module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
56MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
57
58#else
59#define usb_autosuspend_delay 0
60#endif
61
62
63/**
64 * usb_find_alt_setting() - Given a configuration, find the alternate setting
65 * for the given interface.
66 * @config: the configuration to search (not necessarily the current config).
67 * @iface_num: interface number to search in
68 * @alt_num: alternate interface setting number to search for.
69 *
70 * Search the configuration's interface cache for the given alt setting.
71 *
72 * Return: The alternate setting, if found. %NULL otherwise.
73 */
74struct usb_host_interface *usb_find_alt_setting(
75 struct usb_host_config *config,
76 unsigned int iface_num,
77 unsigned int alt_num)
78{
79 struct usb_interface_cache *intf_cache = NULL;
80 int i;
81
82 for (i = 0; i < config->desc.bNumInterfaces; i++) {
83 if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber
84 == iface_num) {
85 intf_cache = config->intf_cache[i];
86 break;
87 }
88 }
89 if (!intf_cache)
90 return NULL;
91 for (i = 0; i < intf_cache->num_altsetting; i++)
92 if (intf_cache->altsetting[i].desc.bAlternateSetting == alt_num)
93 return &intf_cache->altsetting[i];
94
95 printk(KERN_DEBUG "Did not find alt setting %u for intf %u, "
96 "config %u\n", alt_num, iface_num,
97 config->desc.bConfigurationValue);
98 return NULL;
99}
100EXPORT_SYMBOL_GPL(usb_find_alt_setting);
101
102/**
103 * usb_ifnum_to_if - get the interface object with a given interface number
104 * @dev: the device whose current configuration is considered
105 * @ifnum: the desired interface
106 *
107 * This walks the device descriptor for the currently active configuration
108 * to find the interface object with the particular interface number.
109 *
110 * Note that configuration descriptors are not required to assign interface
111 * numbers sequentially, so that it would be incorrect to assume that
112 * the first interface in that descriptor corresponds to interface zero.
113 * This routine helps device drivers avoid such mistakes.
114 * However, you should make sure that you do the right thing with any
115 * alternate settings available for this interfaces.
116 *
117 * Don't call this function unless you are bound to one of the interfaces
118 * on this device or you have locked the device!
119 *
120 * Return: A pointer to the interface that has @ifnum as interface number,
121 * if found. %NULL otherwise.
122 */
123struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
124 unsigned ifnum)
125{
126 struct usb_host_config *config = dev->actconfig;
127 int i;
128
129 if (!config)
130 return NULL;
131 for (i = 0; i < config->desc.bNumInterfaces; i++)
132 if (config->interface[i]->altsetting[0]
133 .desc.bInterfaceNumber == ifnum)
134 return config->interface[i];
135
136 return NULL;
137}
138EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
139
140/**
141 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
142 * @intf: the interface containing the altsetting in question
143 * @altnum: the desired alternate setting number
144 *
145 * This searches the altsetting array of the specified interface for
146 * an entry with the correct bAlternateSetting value.
147 *
148 * Note that altsettings need not be stored sequentially by number, so
149 * it would be incorrect to assume that the first altsetting entry in
150 * the array corresponds to altsetting zero. This routine helps device
151 * drivers avoid such mistakes.
152 *
153 * Don't call this function unless you are bound to the intf interface
154 * or you have locked the device!
155 *
156 * Return: A pointer to the entry of the altsetting array of @intf that
157 * has @altnum as the alternate setting number. %NULL if not found.
158 */
159struct usb_host_interface *usb_altnum_to_altsetting(
160 const struct usb_interface *intf,
161 unsigned int altnum)
162{
163 int i;
164
165 for (i = 0; i < intf->num_altsetting; i++) {
166 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
167 return &intf->altsetting[i];
168 }
169 return NULL;
170}
171EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
172
173struct find_interface_arg {
174 int minor;
175 struct device_driver *drv;
176};
177
178static int __find_interface(struct device *dev, void *data)
179{
180 struct find_interface_arg *arg = data;
181 struct usb_interface *intf;
182
183 if (!is_usb_interface(dev))
184 return 0;
185
186 if (dev->driver != arg->drv)
187 return 0;
188 intf = to_usb_interface(dev);
189 return intf->minor == arg->minor;
190}
191
192/**
193 * usb_find_interface - find usb_interface pointer for driver and device
194 * @drv: the driver whose current configuration is considered
195 * @minor: the minor number of the desired device
196 *
197 * This walks the bus device list and returns a pointer to the interface
198 * with the matching minor and driver. Note, this only works for devices
199 * that share the USB major number.
200 *
201 * Return: A pointer to the interface with the matching major and @minor.
202 */
203struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
204{
205 struct find_interface_arg argb;
206 struct device *dev;
207
208 argb.minor = minor;
209 argb.drv = &drv->drvwrap.driver;
210
211 dev = bus_find_device(&usb_bus_type, NULL, &argb, __find_interface);
212
213 /* Drop reference count from bus_find_device */
214 put_device(dev);
215
216 return dev ? to_usb_interface(dev) : NULL;
217}
218EXPORT_SYMBOL_GPL(usb_find_interface);
219
220struct each_dev_arg {
221 void *data;
222 int (*fn)(struct usb_device *, void *);
223};
224
225static int __each_dev(struct device *dev, void *data)
226{
227 struct each_dev_arg *arg = (struct each_dev_arg *)data;
228
229 /* There are struct usb_interface on the same bus, filter them out */
230 if (!is_usb_device(dev))
231 return 0;
232
233 return arg->fn(container_of(dev, struct usb_device, dev), arg->data);
234}
235
236/**
237 * usb_for_each_dev - iterate over all USB devices in the system
238 * @data: data pointer that will be handed to the callback function
239 * @fn: callback function to be called for each USB device
240 *
241 * Iterate over all USB devices and call @fn for each, passing it @data. If it
242 * returns anything other than 0, we break the iteration prematurely and return
243 * that value.
244 */
245int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *))
246{
247 struct each_dev_arg arg = {data, fn};
248
249 return bus_for_each_dev(&usb_bus_type, NULL, &arg, __each_dev);
250}
251EXPORT_SYMBOL_GPL(usb_for_each_dev);
252
253/**
254 * usb_release_dev - free a usb device structure when all users of it are finished.
255 * @dev: device that's been disconnected
256 *
257 * Will be called only by the device core when all users of this usb device are
258 * done.
259 */
260static void usb_release_dev(struct device *dev)
261{
262 struct usb_device *udev;
263 struct usb_hcd *hcd;
264
265 udev = to_usb_device(dev);
266 hcd = bus_to_hcd(udev->bus);
267
268 usb_destroy_configuration(udev);
269 usb_release_bos_descriptor(udev);
270 usb_put_hcd(hcd);
271 kfree(udev->product);
272 kfree(udev->manufacturer);
273 kfree(udev->serial);
274 kfree(udev);
275}
276
277static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
278{
279 struct usb_device *usb_dev;
280
281 usb_dev = to_usb_device(dev);
282
283 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
284 return -ENOMEM;
285
286 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
287 return -ENOMEM;
288
289 return 0;
290}
291
292#ifdef CONFIG_PM
293
294/* USB device Power-Management thunks.
295 * There's no need to distinguish here between quiescing a USB device
296 * and powering it down; the generic_suspend() routine takes care of
297 * it by skipping the usb_port_suspend() call for a quiesce. And for
298 * USB interfaces there's no difference at all.
299 */
300
301static int usb_dev_prepare(struct device *dev)
302{
303 return 0; /* Implement eventually? */
304}
305
306static void usb_dev_complete(struct device *dev)
307{
308 /* Currently used only for rebinding interfaces */
309 usb_resume_complete(dev);
310}
311
312static int usb_dev_suspend(struct device *dev)
313{
314 return usb_suspend(dev, PMSG_SUSPEND);
315}
316
317static int usb_dev_resume(struct device *dev)
318{
319 return usb_resume(dev, PMSG_RESUME);
320}
321
322static int usb_dev_freeze(struct device *dev)
323{
324 return usb_suspend(dev, PMSG_FREEZE);
325}
326
327static int usb_dev_thaw(struct device *dev)
328{
329 return usb_resume(dev, PMSG_THAW);
330}
331
332static int usb_dev_poweroff(struct device *dev)
333{
334 return usb_suspend(dev, PMSG_HIBERNATE);
335}
336
337static int usb_dev_restore(struct device *dev)
338{
339 return usb_resume(dev, PMSG_RESTORE);
340}
341
342static const struct dev_pm_ops usb_device_pm_ops = {
343 .prepare = usb_dev_prepare,
344 .complete = usb_dev_complete,
345 .suspend = usb_dev_suspend,
346 .resume = usb_dev_resume,
347 .freeze = usb_dev_freeze,
348 .thaw = usb_dev_thaw,
349 .poweroff = usb_dev_poweroff,
350 .restore = usb_dev_restore,
351#ifdef CONFIG_PM_RUNTIME
352 .runtime_suspend = usb_runtime_suspend,
353 .runtime_resume = usb_runtime_resume,
354 .runtime_idle = usb_runtime_idle,
355#endif
356};
357
358#endif /* CONFIG_PM */
359
360
361static char *usb_devnode(struct device *dev,
362 umode_t *mode, kuid_t *uid, kgid_t *gid)
363{
364 struct usb_device *usb_dev;
365
366 usb_dev = to_usb_device(dev);
367 return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
368 usb_dev->bus->busnum, usb_dev->devnum);
369}
370
371struct device_type usb_device_type = {
372 .name = "usb_device",
373 .release = usb_release_dev,
374 .uevent = usb_dev_uevent,
375 .devnode = usb_devnode,
376#ifdef CONFIG_PM
377 .pm = &usb_device_pm_ops,
378#endif
379};
380
381
382/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
383static unsigned usb_bus_is_wusb(struct usb_bus *bus)
384{
385 struct usb_hcd *hcd = container_of(bus, struct usb_hcd, self);
386 return hcd->wireless;
387}
388
389
390/**
391 * usb_alloc_dev - usb device constructor (usbcore-internal)
392 * @parent: hub to which device is connected; null to allocate a root hub
393 * @bus: bus used to access the device
394 * @port1: one-based index of port; ignored for root hubs
395 * Context: !in_interrupt()
396 *
397 * Only hub drivers (including virtual root hub drivers for host
398 * controllers) should ever call this.
399 *
400 * This call may not be used in a non-sleeping context.
401 *
402 * Return: On success, a pointer to the allocated usb device. %NULL on
403 * failure.
404 */
405struct usb_device *usb_alloc_dev(struct usb_device *parent,
406 struct usb_bus *bus, unsigned port1)
407{
408 struct usb_device *dev;
409 struct usb_hcd *usb_hcd = bus_to_hcd(bus);
410 unsigned root_hub = 0;
411
412 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
413 if (!dev)
414 return NULL;
415
416 if (!usb_get_hcd(usb_hcd)) {
417 kfree(dev);
418 return NULL;
419 }
420 /* Root hubs aren't true devices, so don't allocate HCD resources */
421 if (usb_hcd->driver->alloc_dev && parent &&
422 !usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
423 usb_put_hcd(bus_to_hcd(bus));
424 kfree(dev);
425 return NULL;
426 }
427
428 device_initialize(&dev->dev);
429 dev->dev.bus = &usb_bus_type;
430 dev->dev.type = &usb_device_type;
431 dev->dev.groups = usb_device_groups;
432 dev->dev.dma_mask = bus->controller->dma_mask;
433 set_dev_node(&dev->dev, dev_to_node(bus->controller));
434 dev->state = USB_STATE_ATTACHED;
435 dev->lpm_disable_count = 1;
436 atomic_set(&dev->urbnum, 0);
437
438 INIT_LIST_HEAD(&dev->ep0.urb_list);
439 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
440 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
441 /* ep0 maxpacket comes later, from device descriptor */
442 usb_enable_endpoint(dev, &dev->ep0, false);
443 dev->can_submit = 1;
444
445 /* Save readable and stable topology id, distinguishing devices
446 * by location for diagnostics, tools, driver model, etc. The
447 * string is a path along hub ports, from the root. Each device's
448 * dev->devpath will be stable until USB is re-cabled, and hubs
449 * are often labeled with these port numbers. The name isn't
450 * as stable: bus->busnum changes easily from modprobe order,
451 * cardbus or pci hotplugging, and so on.
452 */
453 if (unlikely(!parent)) {
454 dev->devpath[0] = '0';
455 dev->route = 0;
456
457 dev->dev.parent = bus->controller;
458 dev_set_name(&dev->dev, "usb%d", bus->busnum);
459 root_hub = 1;
460 } else {
461 /* match any labeling on the hubs; it's one-based */
462 if (parent->devpath[0] == '0') {
463 snprintf(dev->devpath, sizeof dev->devpath,
464 "%d", port1);
465 /* Root ports are not counted in route string */
466 dev->route = 0;
467 } else {
468 snprintf(dev->devpath, sizeof dev->devpath,
469 "%s.%d", parent->devpath, port1);
470 /* Route string assumes hubs have less than 16 ports */
471 if (port1 < 15)
472 dev->route = parent->route +
473 (port1 << ((parent->level - 1)*4));
474 else
475 dev->route = parent->route +
476 (15 << ((parent->level - 1)*4));
477 }
478
479 dev->dev.parent = &parent->dev;
480 dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
481
482 /* hub driver sets up TT records */
483 }
484
485 dev->portnum = port1;
486 dev->bus = bus;
487 dev->parent = parent;
488 INIT_LIST_HEAD(&dev->filelist);
489
490#ifdef CONFIG_PM
491 pm_runtime_set_autosuspend_delay(&dev->dev,
492 usb_autosuspend_delay * 1000);
493 dev->connect_time = jiffies;
494 dev->active_duration = -jiffies;
495#endif
496 if (root_hub) /* Root hub always ok [and always wired] */
497 dev->authorized = 1;
498 else {
499 dev->authorized = usb_hcd->authorized_default;
500 dev->wusb = usb_bus_is_wusb(bus) ? 1 : 0;
501 }
502 return dev;
503}
504
505/**
506 * usb_get_dev - increments the reference count of the usb device structure
507 * @dev: the device being referenced
508 *
509 * Each live reference to a device should be refcounted.
510 *
511 * Drivers for USB interfaces should normally record such references in
512 * their probe() methods, when they bind to an interface, and release
513 * them by calling usb_put_dev(), in their disconnect() methods.
514 *
515 * Return: A pointer to the device with the incremented reference counter.
516 */
517struct usb_device *usb_get_dev(struct usb_device *dev)
518{
519 if (dev)
520 get_device(&dev->dev);
521 return dev;
522}
523EXPORT_SYMBOL_GPL(usb_get_dev);
524
525/**
526 * usb_put_dev - release a use of the usb device structure
527 * @dev: device that's been disconnected
528 *
529 * Must be called when a user of a device is finished with it. When the last
530 * user of the device calls this function, the memory of the device is freed.
531 */
532void usb_put_dev(struct usb_device *dev)
533{
534 if (dev)
535 put_device(&dev->dev);
536}
537EXPORT_SYMBOL_GPL(usb_put_dev);
538
539/**
540 * usb_get_intf - increments the reference count of the usb interface structure
541 * @intf: the interface being referenced
542 *
543 * Each live reference to a interface must be refcounted.
544 *
545 * Drivers for USB interfaces should normally record such references in
546 * their probe() methods, when they bind to an interface, and release
547 * them by calling usb_put_intf(), in their disconnect() methods.
548 *
549 * Return: A pointer to the interface with the incremented reference counter.
550 */
551struct usb_interface *usb_get_intf(struct usb_interface *intf)
552{
553 if (intf)
554 get_device(&intf->dev);
555 return intf;
556}
557EXPORT_SYMBOL_GPL(usb_get_intf);
558
559/**
560 * usb_put_intf - release a use of the usb interface structure
561 * @intf: interface that's been decremented
562 *
563 * Must be called when a user of an interface is finished with it. When the
564 * last user of the interface calls this function, the memory of the interface
565 * is freed.
566 */
567void usb_put_intf(struct usb_interface *intf)
568{
569 if (intf)
570 put_device(&intf->dev);
571}
572EXPORT_SYMBOL_GPL(usb_put_intf);
573
574/* USB device locking
575 *
576 * USB devices and interfaces are locked using the semaphore in their
577 * embedded struct device. The hub driver guarantees that whenever a
578 * device is connected or disconnected, drivers are called with the
579 * USB device locked as well as their particular interface.
580 *
581 * Complications arise when several devices are to be locked at the same
582 * time. Only hub-aware drivers that are part of usbcore ever have to
583 * do this; nobody else needs to worry about it. The rule for locking
584 * is simple:
585 *
586 * When locking both a device and its parent, always lock the
587 * the parent first.
588 */
589
590/**
591 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
592 * @udev: device that's being locked
593 * @iface: interface bound to the driver making the request (optional)
594 *
595 * Attempts to acquire the device lock, but fails if the device is
596 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
597 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
598 * lock, the routine polls repeatedly. This is to prevent deadlock with
599 * disconnect; in some drivers (such as usb-storage) the disconnect()
600 * or suspend() method will block waiting for a device reset to complete.
601 *
602 * Return: A negative error code for failure, otherwise 0.
603 */
604int usb_lock_device_for_reset(struct usb_device *udev,
605 const struct usb_interface *iface)
606{
607 unsigned long jiffies_expire = jiffies + HZ;
608
609 if (udev->state == USB_STATE_NOTATTACHED)
610 return -ENODEV;
611 if (udev->state == USB_STATE_SUSPENDED)
612 return -EHOSTUNREACH;
613 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
614 iface->condition == USB_INTERFACE_UNBOUND))
615 return -EINTR;
616
617 while (!usb_trylock_device(udev)) {
618
619 /* If we can't acquire the lock after waiting one second,
620 * we're probably deadlocked */
621 if (time_after(jiffies, jiffies_expire))
622 return -EBUSY;
623
624 msleep(15);
625 if (udev->state == USB_STATE_NOTATTACHED)
626 return -ENODEV;
627 if (udev->state == USB_STATE_SUSPENDED)
628 return -EHOSTUNREACH;
629 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
630 iface->condition == USB_INTERFACE_UNBOUND))
631 return -EINTR;
632 }
633 return 0;
634}
635EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
636
637/**
638 * usb_get_current_frame_number - return current bus frame number
639 * @dev: the device whose bus is being queried
640 *
641 * Return: The current frame number for the USB host controller used
642 * with the given USB device. This can be used when scheduling
643 * isochronous requests.
644 *
645 * Note: Different kinds of host controller have different "scheduling
646 * horizons". While one type might support scheduling only 32 frames
647 * into the future, others could support scheduling up to 1024 frames
648 * into the future.
649 *
650 */
651int usb_get_current_frame_number(struct usb_device *dev)
652{
653 return usb_hcd_get_frame_number(dev);
654}
655EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
656
657/*-------------------------------------------------------------------*/
658/*
659 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
660 * extra field of the interface and endpoint descriptor structs.
661 */
662
663int __usb_get_extra_descriptor(char *buffer, unsigned size,
664 unsigned char type, void **ptr)
665{
666 struct usb_descriptor_header *header;
667
668 while (size >= sizeof(struct usb_descriptor_header)) {
669 header = (struct usb_descriptor_header *)buffer;
670
671 if (header->bLength < 2) {
672 printk(KERN_ERR
673 "%s: bogus descriptor, type %d length %d\n",
674 usbcore_name,
675 header->bDescriptorType,
676 header->bLength);
677 return -1;
678 }
679
680 if (header->bDescriptorType == type) {
681 *ptr = header;
682 return 0;
683 }
684
685 buffer += header->bLength;
686 size -= header->bLength;
687 }
688 return -1;
689}
690EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
691
692/**
693 * usb_alloc_coherent - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
694 * @dev: device the buffer will be used with
695 * @size: requested buffer size
696 * @mem_flags: affect whether allocation may block
697 * @dma: used to return DMA address of buffer
698 *
699 * Return: Either null (indicating no buffer could be allocated), or the
700 * cpu-space pointer to a buffer that may be used to perform DMA to the
701 * specified device. Such cpu-space buffers are returned along with the DMA
702 * address (through the pointer provided).
703 *
704 * Note:
705 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
706 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
707 * hardware during URB completion/resubmit. The implementation varies between
708 * platforms, depending on details of how DMA will work to this device.
709 * Using these buffers also eliminates cacheline sharing problems on
710 * architectures where CPU caches are not DMA-coherent. On systems without
711 * bus-snooping caches, these buffers are uncached.
712 *
713 * When the buffer is no longer used, free it with usb_free_coherent().
714 */
715void *usb_alloc_coherent(struct usb_device *dev, size_t size, gfp_t mem_flags,
716 dma_addr_t *dma)
717{
718 if (!dev || !dev->bus)
719 return NULL;
720 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
721}
722EXPORT_SYMBOL_GPL(usb_alloc_coherent);
723
724/**
725 * usb_free_coherent - free memory allocated with usb_alloc_coherent()
726 * @dev: device the buffer was used with
727 * @size: requested buffer size
728 * @addr: CPU address of buffer
729 * @dma: DMA address of buffer
730 *
731 * This reclaims an I/O buffer, letting it be reused. The memory must have
732 * been allocated using usb_alloc_coherent(), and the parameters must match
733 * those provided in that allocation request.
734 */
735void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
736 dma_addr_t dma)
737{
738 if (!dev || !dev->bus)
739 return;
740 if (!addr)
741 return;
742 hcd_buffer_free(dev->bus, size, addr, dma);
743}
744EXPORT_SYMBOL_GPL(usb_free_coherent);
745
746/**
747 * usb_buffer_map - create DMA mapping(s) for an urb
748 * @urb: urb whose transfer_buffer/setup_packet will be mapped
749 *
750 * URB_NO_TRANSFER_DMA_MAP is added to urb->transfer_flags if the operation
751 * succeeds. If the device is connected to this system through a non-DMA
752 * controller, this operation always succeeds.
753 *
754 * This call would normally be used for an urb which is reused, perhaps
755 * as the target of a large periodic transfer, with usb_buffer_dmasync()
756 * calls to synchronize memory and dma state.
757 *
758 * Reverse the effect of this call with usb_buffer_unmap().
759 *
760 * Return: Either %NULL (indicating no buffer could be mapped), or @urb.
761 *
762 */
763#if 0
764struct urb *usb_buffer_map(struct urb *urb)
765{
766 struct usb_bus *bus;
767 struct device *controller;
768
769 if (!urb
770 || !urb->dev
771 || !(bus = urb->dev->bus)
772 || !(controller = bus->controller))
773 return NULL;
774
775 if (controller->dma_mask) {
776 urb->transfer_dma = dma_map_single(controller,
777 urb->transfer_buffer, urb->transfer_buffer_length,
778 usb_pipein(urb->pipe)
779 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
780 /* FIXME generic api broken like pci, can't report errors */
781 /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
782 } else
783 urb->transfer_dma = ~0;
784 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
785 return urb;
786}
787EXPORT_SYMBOL_GPL(usb_buffer_map);
788#endif /* 0 */
789
790/* XXX DISABLED, no users currently. If you wish to re-enable this
791 * XXX please determine whether the sync is to transfer ownership of
792 * XXX the buffer from device to cpu or vice verse, and thusly use the
793 * XXX appropriate _for_{cpu,device}() method. -DaveM
794 */
795#if 0
796
797/**
798 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
799 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
800 */
801void usb_buffer_dmasync(struct urb *urb)
802{
803 struct usb_bus *bus;
804 struct device *controller;
805
806 if (!urb
807 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
808 || !urb->dev
809 || !(bus = urb->dev->bus)
810 || !(controller = bus->controller))
811 return;
812
813 if (controller->dma_mask) {
814 dma_sync_single_for_cpu(controller,
815 urb->transfer_dma, urb->transfer_buffer_length,
816 usb_pipein(urb->pipe)
817 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
818 if (usb_pipecontrol(urb->pipe))
819 dma_sync_single_for_cpu(controller,
820 urb->setup_dma,
821 sizeof(struct usb_ctrlrequest),
822 DMA_TO_DEVICE);
823 }
824}
825EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
826#endif
827
828/**
829 * usb_buffer_unmap - free DMA mapping(s) for an urb
830 * @urb: urb whose transfer_buffer will be unmapped
831 *
832 * Reverses the effect of usb_buffer_map().
833 */
834#if 0
835void usb_buffer_unmap(struct urb *urb)
836{
837 struct usb_bus *bus;
838 struct device *controller;
839
840 if (!urb
841 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
842 || !urb->dev
843 || !(bus = urb->dev->bus)
844 || !(controller = bus->controller))
845 return;
846
847 if (controller->dma_mask) {
848 dma_unmap_single(controller,
849 urb->transfer_dma, urb->transfer_buffer_length,
850 usb_pipein(urb->pipe)
851 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
852 }
853 urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
854}
855EXPORT_SYMBOL_GPL(usb_buffer_unmap);
856#endif /* 0 */
857
858#if 0
859/**
860 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
861 * @dev: device to which the scatterlist will be mapped
862 * @is_in: mapping transfer direction
863 * @sg: the scatterlist to map
864 * @nents: the number of entries in the scatterlist
865 *
866 * Return: Either < 0 (indicating no buffers could be mapped), or the
867 * number of DMA mapping array entries in the scatterlist.
868 *
869 * Note:
870 * The caller is responsible for placing the resulting DMA addresses from
871 * the scatterlist into URB transfer buffer pointers, and for setting the
872 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
873 *
874 * Top I/O rates come from queuing URBs, instead of waiting for each one
875 * to complete before starting the next I/O. This is particularly easy
876 * to do with scatterlists. Just allocate and submit one URB for each DMA
877 * mapping entry returned, stopping on the first error or when all succeed.
878 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
879 *
880 * This call would normally be used when translating scatterlist requests,
881 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
882 * may be able to coalesce mappings for improved I/O efficiency.
883 *
884 * Reverse the effect of this call with usb_buffer_unmap_sg().
885 */
886int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
887 struct scatterlist *sg, int nents)
888{
889 struct usb_bus *bus;
890 struct device *controller;
891
892 if (!dev
893 || !(bus = dev->bus)
894 || !(controller = bus->controller)
895 || !controller->dma_mask)
896 return -EINVAL;
897
898 /* FIXME generic api broken like pci, can't report errors */
899 return dma_map_sg(controller, sg, nents,
900 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
901}
902EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
903#endif
904
905/* XXX DISABLED, no users currently. If you wish to re-enable this
906 * XXX please determine whether the sync is to transfer ownership of
907 * XXX the buffer from device to cpu or vice verse, and thusly use the
908 * XXX appropriate _for_{cpu,device}() method. -DaveM
909 */
910#if 0
911
912/**
913 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
914 * @dev: device to which the scatterlist will be mapped
915 * @is_in: mapping transfer direction
916 * @sg: the scatterlist to synchronize
917 * @n_hw_ents: the positive return value from usb_buffer_map_sg
918 *
919 * Use this when you are re-using a scatterlist's data buffers for
920 * another USB request.
921 */
922void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
923 struct scatterlist *sg, int n_hw_ents)
924{
925 struct usb_bus *bus;
926 struct device *controller;
927
928 if (!dev
929 || !(bus = dev->bus)
930 || !(controller = bus->controller)
931 || !controller->dma_mask)
932 return;
933
934 dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
935 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
936}
937EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
938#endif
939
940#if 0
941/**
942 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
943 * @dev: device to which the scatterlist will be mapped
944 * @is_in: mapping transfer direction
945 * @sg: the scatterlist to unmap
946 * @n_hw_ents: the positive return value from usb_buffer_map_sg
947 *
948 * Reverses the effect of usb_buffer_map_sg().
949 */
950void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
951 struct scatterlist *sg, int n_hw_ents)
952{
953 struct usb_bus *bus;
954 struct device *controller;
955
956 if (!dev
957 || !(bus = dev->bus)
958 || !(controller = bus->controller)
959 || !controller->dma_mask)
960 return;
961
962 dma_unmap_sg(controller, sg, n_hw_ents,
963 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
964}
965EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
966#endif
967
968/* To disable USB, kernel command line is 'nousb' not 'usbcore.nousb' */
969#ifdef MODULE
970module_param(nousb, bool, 0444);
971#else
972core_param(nousb, nousb, bool, 0444);
973#endif
974
975/*
976 * for external read access to <nousb>
977 */
978int usb_disabled(void)
979{
980 return nousb;
981}
982EXPORT_SYMBOL_GPL(usb_disabled);
983
984/*
985 * Notifications of device and interface registration
986 */
987static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
988 void *data)
989{
990 struct device *dev = data;
991
992 switch (action) {
993 case BUS_NOTIFY_ADD_DEVICE:
994 if (dev->type == &usb_device_type)
995 (void) usb_create_sysfs_dev_files(to_usb_device(dev));
996 else if (dev->type == &usb_if_device_type)
997 usb_create_sysfs_intf_files(to_usb_interface(dev));
998 break;
999
1000 case BUS_NOTIFY_DEL_DEVICE:
1001 if (dev->type == &usb_device_type)
1002 usb_remove_sysfs_dev_files(to_usb_device(dev));
1003 else if (dev->type == &usb_if_device_type)
1004 usb_remove_sysfs_intf_files(to_usb_interface(dev));
1005 break;
1006 }
1007 return 0;
1008}
1009
1010static struct notifier_block usb_bus_nb = {
1011 .notifier_call = usb_bus_notify,
1012};
1013
1014struct dentry *usb_debug_root;
1015EXPORT_SYMBOL_GPL(usb_debug_root);
1016
1017static struct dentry *usb_debug_devices;
1018
1019static int usb_debugfs_init(void)
1020{
1021 usb_debug_root = debugfs_create_dir("usb", NULL);
1022 if (!usb_debug_root)
1023 return -ENOENT;
1024
1025 usb_debug_devices = debugfs_create_file("devices", 0444,
1026 usb_debug_root, NULL,
1027 &usbfs_devices_fops);
1028 if (!usb_debug_devices) {
1029 debugfs_remove(usb_debug_root);
1030 usb_debug_root = NULL;
1031 return -ENOENT;
1032 }
1033
1034 return 0;
1035}
1036
1037static void usb_debugfs_cleanup(void)
1038{
1039 debugfs_remove(usb_debug_devices);
1040 debugfs_remove(usb_debug_root);
1041}
1042
1043/*
1044 * Init
1045 */
1046static int __init usb_init(void)
1047{
1048 int retval;
1049 if (nousb) {
1050 pr_info("%s: USB support disabled\n", usbcore_name);
1051 return 0;
1052 }
1053
1054 retval = usb_debugfs_init();
1055 if (retval)
1056 goto out;
1057
1058 usb_acpi_register();
1059 retval = bus_register(&usb_bus_type);
1060 if (retval)
1061 goto bus_register_failed;
1062 retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
1063 if (retval)
1064 goto bus_notifier_failed;
1065 retval = usb_major_init();
1066 if (retval)
1067 goto major_init_failed;
1068 retval = usb_register(&usbfs_driver);
1069 if (retval)
1070 goto driver_register_failed;
1071 retval = usb_devio_init();
1072 if (retval)
1073 goto usb_devio_init_failed;
1074 retval = usb_hub_init();
1075 if (retval)
1076 goto hub_init_failed;
1077 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
1078 if (!retval)
1079 goto out;
1080
1081 usb_hub_cleanup();
1082hub_init_failed:
1083 usb_devio_cleanup();
1084usb_devio_init_failed:
1085 usb_deregister(&usbfs_driver);
1086driver_register_failed:
1087 usb_major_cleanup();
1088major_init_failed:
1089 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1090bus_notifier_failed:
1091 bus_unregister(&usb_bus_type);
1092bus_register_failed:
1093 usb_acpi_unregister();
1094 usb_debugfs_cleanup();
1095out:
1096 return retval;
1097}
1098
1099/*
1100 * Cleanup
1101 */
1102static void __exit usb_exit(void)
1103{
1104 /* This will matter if shutdown/reboot does exitcalls. */
1105 if (nousb)
1106 return;
1107
1108 usb_deregister_device_driver(&usb_generic_driver);
1109 usb_major_cleanup();
1110 usb_deregister(&usbfs_driver);
1111 usb_devio_cleanup();
1112 usb_hub_cleanup();
1113 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1114 bus_unregister(&usb_bus_type);
1115 usb_acpi_unregister();
1116 usb_debugfs_cleanup();
1117}
1118
1119subsys_initcall(usb_init);
1120module_exit(usb_exit);
1121MODULE_LICENSE("GPL");