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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 int nousb; /* Disable USB when built into kernel image */
51
52#ifdef CONFIG_USB_SUSPEND
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 */
72struct usb_host_interface *usb_find_alt_setting(
73 struct usb_host_config *config,
74 unsigned int iface_num,
75 unsigned int alt_num)
76{
77 struct usb_interface_cache *intf_cache = NULL;
78 int i;
79
80 for (i = 0; i < config->desc.bNumInterfaces; i++) {
81 if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber
82 == iface_num) {
83 intf_cache = config->intf_cache[i];
84 break;
85 }
86 }
87 if (!intf_cache)
88 return NULL;
89 for (i = 0; i < intf_cache->num_altsetting; i++)
90 if (intf_cache->altsetting[i].desc.bAlternateSetting == alt_num)
91 return &intf_cache->altsetting[i];
92
93 printk(KERN_DEBUG "Did not find alt setting %u for intf %u, "
94 "config %u\n", alt_num, iface_num,
95 config->desc.bConfigurationValue);
96 return NULL;
97}
98EXPORT_SYMBOL_GPL(usb_find_alt_setting);
99
100/**
101 * usb_ifnum_to_if - get the interface object with a given interface number
102 * @dev: the device whose current configuration is considered
103 * @ifnum: the desired interface
104 *
105 * This walks the device descriptor for the currently active configuration
106 * and returns a pointer to the interface with that particular interface
107 * number, or null.
108 *
109 * Note that configuration descriptors are not required to assign interface
110 * numbers sequentially, so that it would be incorrect to assume that
111 * the first interface in that descriptor corresponds to interface zero.
112 * This routine helps device drivers avoid such mistakes.
113 * However, you should make sure that you do the right thing with any
114 * alternate settings available for this interfaces.
115 *
116 * Don't call this function unless you are bound to one of the interfaces
117 * on this device or you have locked the device!
118 */
119struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
120 unsigned ifnum)
121{
122 struct usb_host_config *config = dev->actconfig;
123 int i;
124
125 if (!config)
126 return NULL;
127 for (i = 0; i < config->desc.bNumInterfaces; i++)
128 if (config->interface[i]->altsetting[0]
129 .desc.bInterfaceNumber == ifnum)
130 return config->interface[i];
131
132 return NULL;
133}
134EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
135
136/**
137 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
138 * @intf: the interface containing the altsetting in question
139 * @altnum: the desired alternate setting number
140 *
141 * This searches the altsetting array of the specified interface for
142 * an entry with the correct bAlternateSetting value and returns a pointer
143 * to that entry, or null.
144 *
145 * Note that altsettings need not be stored sequentially by number, so
146 * it would be incorrect to assume that the first altsetting entry in
147 * the array corresponds to altsetting zero. This routine helps device
148 * drivers avoid such mistakes.
149 *
150 * Don't call this function unless you are bound to the intf interface
151 * or you have locked the device!
152 */
153struct usb_host_interface *usb_altnum_to_altsetting(
154 const struct usb_interface *intf,
155 unsigned int altnum)
156{
157 int i;
158
159 for (i = 0; i < intf->num_altsetting; i++) {
160 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
161 return &intf->altsetting[i];
162 }
163 return NULL;
164}
165EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
166
167struct find_interface_arg {
168 int minor;
169 struct device_driver *drv;
170};
171
172static int __find_interface(struct device *dev, void *data)
173{
174 struct find_interface_arg *arg = data;
175 struct usb_interface *intf;
176
177 if (!is_usb_interface(dev))
178 return 0;
179
180 if (dev->driver != arg->drv)
181 return 0;
182 intf = to_usb_interface(dev);
183 return intf->minor == arg->minor;
184}
185
186/**
187 * usb_find_interface - find usb_interface pointer for driver and device
188 * @drv: the driver whose current configuration is considered
189 * @minor: the minor number of the desired device
190 *
191 * This walks the bus device list and returns a pointer to the interface
192 * with the matching minor and driver. Note, this only works for devices
193 * that share the USB major number.
194 */
195struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
196{
197 struct find_interface_arg argb;
198 struct device *dev;
199
200 argb.minor = minor;
201 argb.drv = &drv->drvwrap.driver;
202
203 dev = bus_find_device(&usb_bus_type, NULL, &argb, __find_interface);
204
205 /* Drop reference count from bus_find_device */
206 put_device(dev);
207
208 return dev ? to_usb_interface(dev) : NULL;
209}
210EXPORT_SYMBOL_GPL(usb_find_interface);
211
212/**
213 * usb_release_dev - free a usb device structure when all users of it are finished.
214 * @dev: device that's been disconnected
215 *
216 * Will be called only by the device core when all users of this usb device are
217 * done.
218 */
219static void usb_release_dev(struct device *dev)
220{
221 struct usb_device *udev;
222 struct usb_hcd *hcd;
223
224 udev = to_usb_device(dev);
225 hcd = bus_to_hcd(udev->bus);
226
227 usb_destroy_configuration(udev);
228 usb_put_hcd(hcd);
229 kfree(udev->product);
230 kfree(udev->manufacturer);
231 kfree(udev->serial);
232 kfree(udev);
233}
234
235#ifdef CONFIG_HOTPLUG
236static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
237{
238 struct usb_device *usb_dev;
239
240 usb_dev = to_usb_device(dev);
241
242 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
243 return -ENOMEM;
244
245 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
246 return -ENOMEM;
247
248 return 0;
249}
250
251#else
252
253static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
254{
255 return -ENODEV;
256}
257#endif /* CONFIG_HOTPLUG */
258
259#ifdef CONFIG_PM
260
261/* USB device Power-Management thunks.
262 * There's no need to distinguish here between quiescing a USB device
263 * and powering it down; the generic_suspend() routine takes care of
264 * it by skipping the usb_port_suspend() call for a quiesce. And for
265 * USB interfaces there's no difference at all.
266 */
267
268static int usb_dev_prepare(struct device *dev)
269{
270 return 0; /* Implement eventually? */
271}
272
273static void usb_dev_complete(struct device *dev)
274{
275 /* Currently used only for rebinding interfaces */
276 usb_resume(dev, PMSG_ON); /* FIXME: change to PMSG_COMPLETE */
277}
278
279static int usb_dev_suspend(struct device *dev)
280{
281 return usb_suspend(dev, PMSG_SUSPEND);
282}
283
284static int usb_dev_resume(struct device *dev)
285{
286 return usb_resume(dev, PMSG_RESUME);
287}
288
289static int usb_dev_freeze(struct device *dev)
290{
291 return usb_suspend(dev, PMSG_FREEZE);
292}
293
294static int usb_dev_thaw(struct device *dev)
295{
296 return usb_resume(dev, PMSG_THAW);
297}
298
299static int usb_dev_poweroff(struct device *dev)
300{
301 return usb_suspend(dev, PMSG_HIBERNATE);
302}
303
304static int usb_dev_restore(struct device *dev)
305{
306 return usb_resume(dev, PMSG_RESTORE);
307}
308
309static const struct dev_pm_ops usb_device_pm_ops = {
310 .prepare = usb_dev_prepare,
311 .complete = usb_dev_complete,
312 .suspend = usb_dev_suspend,
313 .resume = usb_dev_resume,
314 .freeze = usb_dev_freeze,
315 .thaw = usb_dev_thaw,
316 .poweroff = usb_dev_poweroff,
317 .restore = usb_dev_restore,
318#ifdef CONFIG_USB_SUSPEND
319 .runtime_suspend = usb_runtime_suspend,
320 .runtime_resume = usb_runtime_resume,
321 .runtime_idle = usb_runtime_idle,
322#endif
323};
324
325#endif /* CONFIG_PM */
326
327
328static char *usb_devnode(struct device *dev, mode_t *mode)
329{
330 struct usb_device *usb_dev;
331
332 usb_dev = to_usb_device(dev);
333 return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
334 usb_dev->bus->busnum, usb_dev->devnum);
335}
336
337struct device_type usb_device_type = {
338 .name = "usb_device",
339 .release = usb_release_dev,
340 .uevent = usb_dev_uevent,
341 .devnode = usb_devnode,
342#ifdef CONFIG_PM
343 .pm = &usb_device_pm_ops,
344#endif
345};
346
347
348/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
349static unsigned usb_bus_is_wusb(struct usb_bus *bus)
350{
351 struct usb_hcd *hcd = container_of(bus, struct usb_hcd, self);
352 return hcd->wireless;
353}
354
355
356/**
357 * usb_alloc_dev - usb device constructor (usbcore-internal)
358 * @parent: hub to which device is connected; null to allocate a root hub
359 * @bus: bus used to access the device
360 * @port1: one-based index of port; ignored for root hubs
361 * Context: !in_interrupt()
362 *
363 * Only hub drivers (including virtual root hub drivers for host
364 * controllers) should ever call this.
365 *
366 * This call may not be used in a non-sleeping context.
367 */
368struct usb_device *usb_alloc_dev(struct usb_device *parent,
369 struct usb_bus *bus, unsigned port1)
370{
371 struct usb_device *dev;
372 struct usb_hcd *usb_hcd = container_of(bus, struct usb_hcd, self);
373 unsigned root_hub = 0;
374
375 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
376 if (!dev)
377 return NULL;
378
379 if (!usb_get_hcd(bus_to_hcd(bus))) {
380 kfree(dev);
381 return NULL;
382 }
383 /* Root hubs aren't true devices, so don't allocate HCD resources */
384 if (usb_hcd->driver->alloc_dev && parent &&
385 !usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
386 usb_put_hcd(bus_to_hcd(bus));
387 kfree(dev);
388 return NULL;
389 }
390
391 device_initialize(&dev->dev);
392 dev->dev.bus = &usb_bus_type;
393 dev->dev.type = &usb_device_type;
394 dev->dev.groups = usb_device_groups;
395 dev->dev.dma_mask = bus->controller->dma_mask;
396 set_dev_node(&dev->dev, dev_to_node(bus->controller));
397 dev->state = USB_STATE_ATTACHED;
398 atomic_set(&dev->urbnum, 0);
399
400 INIT_LIST_HEAD(&dev->ep0.urb_list);
401 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
402 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
403 /* ep0 maxpacket comes later, from device descriptor */
404 usb_enable_endpoint(dev, &dev->ep0, false);
405 dev->can_submit = 1;
406
407 /* Save readable and stable topology id, distinguishing devices
408 * by location for diagnostics, tools, driver model, etc. The
409 * string is a path along hub ports, from the root. Each device's
410 * dev->devpath will be stable until USB is re-cabled, and hubs
411 * are often labeled with these port numbers. The name isn't
412 * as stable: bus->busnum changes easily from modprobe order,
413 * cardbus or pci hotplugging, and so on.
414 */
415 if (unlikely(!parent)) {
416 dev->devpath[0] = '0';
417 dev->route = 0;
418
419 dev->dev.parent = bus->controller;
420 dev_set_name(&dev->dev, "usb%d", bus->busnum);
421 root_hub = 1;
422 } else {
423 /* match any labeling on the hubs; it's one-based */
424 if (parent->devpath[0] == '0') {
425 snprintf(dev->devpath, sizeof dev->devpath,
426 "%d", port1);
427 /* Root ports are not counted in route string */
428 dev->route = 0;
429 } else {
430 snprintf(dev->devpath, sizeof dev->devpath,
431 "%s.%d", parent->devpath, port1);
432 /* Route string assumes hubs have less than 16 ports */
433 if (port1 < 15)
434 dev->route = parent->route +
435 (port1 << ((parent->level - 1)*4));
436 else
437 dev->route = parent->route +
438 (15 << ((parent->level - 1)*4));
439 }
440
441 dev->dev.parent = &parent->dev;
442 dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
443
444 /* hub driver sets up TT records */
445 }
446
447 dev->portnum = port1;
448 dev->bus = bus;
449 dev->parent = parent;
450 INIT_LIST_HEAD(&dev->filelist);
451
452#ifdef CONFIG_PM
453 pm_runtime_set_autosuspend_delay(&dev->dev,
454 usb_autosuspend_delay * 1000);
455 dev->connect_time = jiffies;
456 dev->active_duration = -jiffies;
457#endif
458 if (root_hub) /* Root hub always ok [and always wired] */
459 dev->authorized = 1;
460 else {
461 dev->authorized = usb_hcd->authorized_default;
462 dev->wusb = usb_bus_is_wusb(bus)? 1 : 0;
463 }
464 return dev;
465}
466
467/**
468 * usb_get_dev - increments the reference count of the usb device structure
469 * @dev: the device being referenced
470 *
471 * Each live reference to a device should be refcounted.
472 *
473 * Drivers for USB interfaces should normally record such references in
474 * their probe() methods, when they bind to an interface, and release
475 * them by calling usb_put_dev(), in their disconnect() methods.
476 *
477 * A pointer to the device with the incremented reference counter is returned.
478 */
479struct usb_device *usb_get_dev(struct usb_device *dev)
480{
481 if (dev)
482 get_device(&dev->dev);
483 return dev;
484}
485EXPORT_SYMBOL_GPL(usb_get_dev);
486
487/**
488 * usb_put_dev - release a use of the usb device structure
489 * @dev: device that's been disconnected
490 *
491 * Must be called when a user of a device is finished with it. When the last
492 * user of the device calls this function, the memory of the device is freed.
493 */
494void usb_put_dev(struct usb_device *dev)
495{
496 if (dev)
497 put_device(&dev->dev);
498}
499EXPORT_SYMBOL_GPL(usb_put_dev);
500
501/**
502 * usb_get_intf - increments the reference count of the usb interface structure
503 * @intf: the interface being referenced
504 *
505 * Each live reference to a interface must be refcounted.
506 *
507 * Drivers for USB interfaces should normally record such references in
508 * their probe() methods, when they bind to an interface, and release
509 * them by calling usb_put_intf(), in their disconnect() methods.
510 *
511 * A pointer to the interface with the incremented reference counter is
512 * returned.
513 */
514struct usb_interface *usb_get_intf(struct usb_interface *intf)
515{
516 if (intf)
517 get_device(&intf->dev);
518 return intf;
519}
520EXPORT_SYMBOL_GPL(usb_get_intf);
521
522/**
523 * usb_put_intf - release a use of the usb interface structure
524 * @intf: interface that's been decremented
525 *
526 * Must be called when a user of an interface is finished with it. When the
527 * last user of the interface calls this function, the memory of the interface
528 * is freed.
529 */
530void usb_put_intf(struct usb_interface *intf)
531{
532 if (intf)
533 put_device(&intf->dev);
534}
535EXPORT_SYMBOL_GPL(usb_put_intf);
536
537/* USB device locking
538 *
539 * USB devices and interfaces are locked using the semaphore in their
540 * embedded struct device. The hub driver guarantees that whenever a
541 * device is connected or disconnected, drivers are called with the
542 * USB device locked as well as their particular interface.
543 *
544 * Complications arise when several devices are to be locked at the same
545 * time. Only hub-aware drivers that are part of usbcore ever have to
546 * do this; nobody else needs to worry about it. The rule for locking
547 * is simple:
548 *
549 * When locking both a device and its parent, always lock the
550 * the parent first.
551 */
552
553/**
554 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
555 * @udev: device that's being locked
556 * @iface: interface bound to the driver making the request (optional)
557 *
558 * Attempts to acquire the device lock, but fails if the device is
559 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
560 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
561 * lock, the routine polls repeatedly. This is to prevent deadlock with
562 * disconnect; in some drivers (such as usb-storage) the disconnect()
563 * or suspend() method will block waiting for a device reset to complete.
564 *
565 * Returns a negative error code for failure, otherwise 0.
566 */
567int usb_lock_device_for_reset(struct usb_device *udev,
568 const struct usb_interface *iface)
569{
570 unsigned long jiffies_expire = jiffies + HZ;
571
572 if (udev->state == USB_STATE_NOTATTACHED)
573 return -ENODEV;
574 if (udev->state == USB_STATE_SUSPENDED)
575 return -EHOSTUNREACH;
576 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
577 iface->condition == USB_INTERFACE_UNBOUND))
578 return -EINTR;
579
580 while (!usb_trylock_device(udev)) {
581
582 /* If we can't acquire the lock after waiting one second,
583 * we're probably deadlocked */
584 if (time_after(jiffies, jiffies_expire))
585 return -EBUSY;
586
587 msleep(15);
588 if (udev->state == USB_STATE_NOTATTACHED)
589 return -ENODEV;
590 if (udev->state == USB_STATE_SUSPENDED)
591 return -EHOSTUNREACH;
592 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
593 iface->condition == USB_INTERFACE_UNBOUND))
594 return -EINTR;
595 }
596 return 0;
597}
598EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
599
600/**
601 * usb_get_current_frame_number - return current bus frame number
602 * @dev: the device whose bus is being queried
603 *
604 * Returns the current frame number for the USB host controller
605 * used with the given USB device. This can be used when scheduling
606 * isochronous requests.
607 *
608 * Note that different kinds of host controller have different
609 * "scheduling horizons". While one type might support scheduling only
610 * 32 frames into the future, others could support scheduling up to
611 * 1024 frames into the future.
612 */
613int usb_get_current_frame_number(struct usb_device *dev)
614{
615 return usb_hcd_get_frame_number(dev);
616}
617EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
618
619/*-------------------------------------------------------------------*/
620/*
621 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
622 * extra field of the interface and endpoint descriptor structs.
623 */
624
625int __usb_get_extra_descriptor(char *buffer, unsigned size,
626 unsigned char type, void **ptr)
627{
628 struct usb_descriptor_header *header;
629
630 while (size >= sizeof(struct usb_descriptor_header)) {
631 header = (struct usb_descriptor_header *)buffer;
632
633 if (header->bLength < 2) {
634 printk(KERN_ERR
635 "%s: bogus descriptor, type %d length %d\n",
636 usbcore_name,
637 header->bDescriptorType,
638 header->bLength);
639 return -1;
640 }
641
642 if (header->bDescriptorType == type) {
643 *ptr = header;
644 return 0;
645 }
646
647 buffer += header->bLength;
648 size -= header->bLength;
649 }
650 return -1;
651}
652EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
653
654/**
655 * usb_alloc_coherent - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
656 * @dev: device the buffer will be used with
657 * @size: requested buffer size
658 * @mem_flags: affect whether allocation may block
659 * @dma: used to return DMA address of buffer
660 *
661 * Return value is either null (indicating no buffer could be allocated), or
662 * the cpu-space pointer to a buffer that may be used to perform DMA to the
663 * specified device. Such cpu-space buffers are returned along with the DMA
664 * address (through the pointer provided).
665 *
666 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
667 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
668 * hardware during URB completion/resubmit. The implementation varies between
669 * platforms, depending on details of how DMA will work to this device.
670 * Using these buffers also eliminates cacheline sharing problems on
671 * architectures where CPU caches are not DMA-coherent. On systems without
672 * bus-snooping caches, these buffers are uncached.
673 *
674 * When the buffer is no longer used, free it with usb_free_coherent().
675 */
676void *usb_alloc_coherent(struct usb_device *dev, size_t size, gfp_t mem_flags,
677 dma_addr_t *dma)
678{
679 if (!dev || !dev->bus)
680 return NULL;
681 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
682}
683EXPORT_SYMBOL_GPL(usb_alloc_coherent);
684
685/**
686 * usb_free_coherent - free memory allocated with usb_alloc_coherent()
687 * @dev: device the buffer was used with
688 * @size: requested buffer size
689 * @addr: CPU address of buffer
690 * @dma: DMA address of buffer
691 *
692 * This reclaims an I/O buffer, letting it be reused. The memory must have
693 * been allocated using usb_alloc_coherent(), and the parameters must match
694 * those provided in that allocation request.
695 */
696void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
697 dma_addr_t dma)
698{
699 if (!dev || !dev->bus)
700 return;
701 if (!addr)
702 return;
703 hcd_buffer_free(dev->bus, size, addr, dma);
704}
705EXPORT_SYMBOL_GPL(usb_free_coherent);
706
707/**
708 * usb_buffer_map - create DMA mapping(s) for an urb
709 * @urb: urb whose transfer_buffer/setup_packet will be mapped
710 *
711 * Return value is either null (indicating no buffer could be mapped), or
712 * the parameter. URB_NO_TRANSFER_DMA_MAP is
713 * added to urb->transfer_flags if the operation succeeds. If the device
714 * is connected to this system through a non-DMA controller, this operation
715 * always succeeds.
716 *
717 * This call would normally be used for an urb which is reused, perhaps
718 * as the target of a large periodic transfer, with usb_buffer_dmasync()
719 * calls to synchronize memory and dma state.
720 *
721 * Reverse the effect of this call with usb_buffer_unmap().
722 */
723#if 0
724struct urb *usb_buffer_map(struct urb *urb)
725{
726 struct usb_bus *bus;
727 struct device *controller;
728
729 if (!urb
730 || !urb->dev
731 || !(bus = urb->dev->bus)
732 || !(controller = bus->controller))
733 return NULL;
734
735 if (controller->dma_mask) {
736 urb->transfer_dma = dma_map_single(controller,
737 urb->transfer_buffer, urb->transfer_buffer_length,
738 usb_pipein(urb->pipe)
739 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
740 /* FIXME generic api broken like pci, can't report errors */
741 /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
742 } else
743 urb->transfer_dma = ~0;
744 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
745 return urb;
746}
747EXPORT_SYMBOL_GPL(usb_buffer_map);
748#endif /* 0 */
749
750/* XXX DISABLED, no users currently. If you wish to re-enable this
751 * XXX please determine whether the sync is to transfer ownership of
752 * XXX the buffer from device to cpu or vice verse, and thusly use the
753 * XXX appropriate _for_{cpu,device}() method. -DaveM
754 */
755#if 0
756
757/**
758 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
759 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
760 */
761void usb_buffer_dmasync(struct urb *urb)
762{
763 struct usb_bus *bus;
764 struct device *controller;
765
766 if (!urb
767 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
768 || !urb->dev
769 || !(bus = urb->dev->bus)
770 || !(controller = bus->controller))
771 return;
772
773 if (controller->dma_mask) {
774 dma_sync_single_for_cpu(controller,
775 urb->transfer_dma, urb->transfer_buffer_length,
776 usb_pipein(urb->pipe)
777 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
778 if (usb_pipecontrol(urb->pipe))
779 dma_sync_single_for_cpu(controller,
780 urb->setup_dma,
781 sizeof(struct usb_ctrlrequest),
782 DMA_TO_DEVICE);
783 }
784}
785EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
786#endif
787
788/**
789 * usb_buffer_unmap - free DMA mapping(s) for an urb
790 * @urb: urb whose transfer_buffer will be unmapped
791 *
792 * Reverses the effect of usb_buffer_map().
793 */
794#if 0
795void usb_buffer_unmap(struct urb *urb)
796{
797 struct usb_bus *bus;
798 struct device *controller;
799
800 if (!urb
801 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
802 || !urb->dev
803 || !(bus = urb->dev->bus)
804 || !(controller = bus->controller))
805 return;
806
807 if (controller->dma_mask) {
808 dma_unmap_single(controller,
809 urb->transfer_dma, urb->transfer_buffer_length,
810 usb_pipein(urb->pipe)
811 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
812 }
813 urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
814}
815EXPORT_SYMBOL_GPL(usb_buffer_unmap);
816#endif /* 0 */
817
818#if 0
819/**
820 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
821 * @dev: device to which the scatterlist will be mapped
822 * @is_in: mapping transfer direction
823 * @sg: the scatterlist to map
824 * @nents: the number of entries in the scatterlist
825 *
826 * Return value is either < 0 (indicating no buffers could be mapped), or
827 * the number of DMA mapping array entries in the scatterlist.
828 *
829 * The caller is responsible for placing the resulting DMA addresses from
830 * the scatterlist into URB transfer buffer pointers, and for setting the
831 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
832 *
833 * Top I/O rates come from queuing URBs, instead of waiting for each one
834 * to complete before starting the next I/O. This is particularly easy
835 * to do with scatterlists. Just allocate and submit one URB for each DMA
836 * mapping entry returned, stopping on the first error or when all succeed.
837 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
838 *
839 * This call would normally be used when translating scatterlist requests,
840 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
841 * may be able to coalesce mappings for improved I/O efficiency.
842 *
843 * Reverse the effect of this call with usb_buffer_unmap_sg().
844 */
845int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
846 struct scatterlist *sg, int nents)
847{
848 struct usb_bus *bus;
849 struct device *controller;
850
851 if (!dev
852 || !(bus = dev->bus)
853 || !(controller = bus->controller)
854 || !controller->dma_mask)
855 return -EINVAL;
856
857 /* FIXME generic api broken like pci, can't report errors */
858 return dma_map_sg(controller, sg, nents,
859 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
860}
861EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
862#endif
863
864/* XXX DISABLED, no users currently. If you wish to re-enable this
865 * XXX please determine whether the sync is to transfer ownership of
866 * XXX the buffer from device to cpu or vice verse, and thusly use the
867 * XXX appropriate _for_{cpu,device}() method. -DaveM
868 */
869#if 0
870
871/**
872 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
873 * @dev: device to which the scatterlist will be mapped
874 * @is_in: mapping transfer direction
875 * @sg: the scatterlist to synchronize
876 * @n_hw_ents: the positive return value from usb_buffer_map_sg
877 *
878 * Use this when you are re-using a scatterlist's data buffers for
879 * another USB request.
880 */
881void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
882 struct scatterlist *sg, int n_hw_ents)
883{
884 struct usb_bus *bus;
885 struct device *controller;
886
887 if (!dev
888 || !(bus = dev->bus)
889 || !(controller = bus->controller)
890 || !controller->dma_mask)
891 return;
892
893 dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
894 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
895}
896EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
897#endif
898
899#if 0
900/**
901 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
902 * @dev: device to which the scatterlist will be mapped
903 * @is_in: mapping transfer direction
904 * @sg: the scatterlist to unmap
905 * @n_hw_ents: the positive return value from usb_buffer_map_sg
906 *
907 * Reverses the effect of usb_buffer_map_sg().
908 */
909void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
910 struct scatterlist *sg, int n_hw_ents)
911{
912 struct usb_bus *bus;
913 struct device *controller;
914
915 if (!dev
916 || !(bus = dev->bus)
917 || !(controller = bus->controller)
918 || !controller->dma_mask)
919 return;
920
921 dma_unmap_sg(controller, sg, n_hw_ents,
922 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
923}
924EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
925#endif
926
927/* To disable USB, kernel command line is 'nousb' not 'usbcore.nousb' */
928#ifdef MODULE
929module_param(nousb, bool, 0444);
930#else
931core_param(nousb, nousb, bool, 0444);
932#endif
933
934/*
935 * for external read access to <nousb>
936 */
937int usb_disabled(void)
938{
939 return nousb;
940}
941EXPORT_SYMBOL_GPL(usb_disabled);
942
943/*
944 * Notifications of device and interface registration
945 */
946static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
947 void *data)
948{
949 struct device *dev = data;
950
951 switch (action) {
952 case BUS_NOTIFY_ADD_DEVICE:
953 if (dev->type == &usb_device_type)
954 (void) usb_create_sysfs_dev_files(to_usb_device(dev));
955 else if (dev->type == &usb_if_device_type)
956 usb_create_sysfs_intf_files(to_usb_interface(dev));
957 break;
958
959 case BUS_NOTIFY_DEL_DEVICE:
960 if (dev->type == &usb_device_type)
961 usb_remove_sysfs_dev_files(to_usb_device(dev));
962 else if (dev->type == &usb_if_device_type)
963 usb_remove_sysfs_intf_files(to_usb_interface(dev));
964 break;
965 }
966 return 0;
967}
968
969static struct notifier_block usb_bus_nb = {
970 .notifier_call = usb_bus_notify,
971};
972
973struct dentry *usb_debug_root;
974EXPORT_SYMBOL_GPL(usb_debug_root);
975
976static struct dentry *usb_debug_devices;
977
978static int usb_debugfs_init(void)
979{
980 usb_debug_root = debugfs_create_dir("usb", NULL);
981 if (!usb_debug_root)
982 return -ENOENT;
983
984 usb_debug_devices = debugfs_create_file("devices", 0444,
985 usb_debug_root, NULL,
986 &usbfs_devices_fops);
987 if (!usb_debug_devices) {
988 debugfs_remove(usb_debug_root);
989 usb_debug_root = NULL;
990 return -ENOENT;
991 }
992
993 return 0;
994}
995
996static void usb_debugfs_cleanup(void)
997{
998 debugfs_remove(usb_debug_devices);
999 debugfs_remove(usb_debug_root);
1000}
1001
1002/*
1003 * Init
1004 */
1005static int __init usb_init(void)
1006{
1007 int retval;
1008 if (nousb) {
1009 pr_info("%s: USB support disabled\n", usbcore_name);
1010 return 0;
1011 }
1012
1013 retval = usb_debugfs_init();
1014 if (retval)
1015 goto out;
1016
1017 retval = bus_register(&usb_bus_type);
1018 if (retval)
1019 goto bus_register_failed;
1020 retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
1021 if (retval)
1022 goto bus_notifier_failed;
1023 retval = usb_major_init();
1024 if (retval)
1025 goto major_init_failed;
1026 retval = usb_register(&usbfs_driver);
1027 if (retval)
1028 goto driver_register_failed;
1029 retval = usb_devio_init();
1030 if (retval)
1031 goto usb_devio_init_failed;
1032 retval = usbfs_init();
1033 if (retval)
1034 goto fs_init_failed;
1035 retval = usb_hub_init();
1036 if (retval)
1037 goto hub_init_failed;
1038 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
1039 if (!retval)
1040 goto out;
1041
1042 usb_hub_cleanup();
1043hub_init_failed:
1044 usbfs_cleanup();
1045fs_init_failed:
1046 usb_devio_cleanup();
1047usb_devio_init_failed:
1048 usb_deregister(&usbfs_driver);
1049driver_register_failed:
1050 usb_major_cleanup();
1051major_init_failed:
1052 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1053bus_notifier_failed:
1054 bus_unregister(&usb_bus_type);
1055bus_register_failed:
1056 usb_debugfs_cleanup();
1057out:
1058 return retval;
1059}
1060
1061/*
1062 * Cleanup
1063 */
1064static void __exit usb_exit(void)
1065{
1066 /* This will matter if shutdown/reboot does exitcalls. */
1067 if (nousb)
1068 return;
1069
1070 usb_deregister_device_driver(&usb_generic_driver);
1071 usb_major_cleanup();
1072 usbfs_cleanup();
1073 usb_deregister(&usbfs_driver);
1074 usb_devio_cleanup();
1075 usb_hub_cleanup();
1076 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1077 bus_unregister(&usb_bus_type);
1078 usb_debugfs_cleanup();
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 * Released under the GPLv2 only.
16 * SPDX-License-Identifier: GPL-2.0
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 * It should be considered a slave, with no callbacks. Callbacks
24 * are evil.
25 */
26
27#include <linux/module.h>
28#include <linux/moduleparam.h>
29#include <linux/string.h>
30#include <linux/bitops.h>
31#include <linux/slab.h>
32#include <linux/interrupt.h> /* for in_interrupt() */
33#include <linux/kmod.h>
34#include <linux/init.h>
35#include <linux/spinlock.h>
36#include <linux/errno.h>
37#include <linux/usb.h>
38#include <linux/usb/hcd.h>
39#include <linux/mutex.h>
40#include <linux/workqueue.h>
41#include <linux/debugfs.h>
42#include <linux/usb/of.h>
43
44#include <asm/io.h>
45#include <linux/scatterlist.h>
46#include <linux/mm.h>
47#include <linux/dma-mapping.h>
48
49#include "usb.h"
50
51
52const char *usbcore_name = "usbcore";
53
54static bool nousb; /* Disable USB when built into kernel image */
55
56module_param(nousb, bool, 0444);
57
58/*
59 * for external read access to <nousb>
60 */
61int usb_disabled(void)
62{
63 return nousb;
64}
65EXPORT_SYMBOL_GPL(usb_disabled);
66
67#ifdef CONFIG_PM
68static int usb_autosuspend_delay = 2; /* Default delay value,
69 * in seconds */
70module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
71MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
72
73#else
74#define usb_autosuspend_delay 0
75#endif
76
77
78/**
79 * usb_find_alt_setting() - Given a configuration, find the alternate setting
80 * for the given interface.
81 * @config: the configuration to search (not necessarily the current config).
82 * @iface_num: interface number to search in
83 * @alt_num: alternate interface setting number to search for.
84 *
85 * Search the configuration's interface cache for the given alt setting.
86 *
87 * Return: The alternate setting, if found. %NULL otherwise.
88 */
89struct usb_host_interface *usb_find_alt_setting(
90 struct usb_host_config *config,
91 unsigned int iface_num,
92 unsigned int alt_num)
93{
94 struct usb_interface_cache *intf_cache = NULL;
95 int i;
96
97 for (i = 0; i < config->desc.bNumInterfaces; i++) {
98 if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber
99 == iface_num) {
100 intf_cache = config->intf_cache[i];
101 break;
102 }
103 }
104 if (!intf_cache)
105 return NULL;
106 for (i = 0; i < intf_cache->num_altsetting; i++)
107 if (intf_cache->altsetting[i].desc.bAlternateSetting == alt_num)
108 return &intf_cache->altsetting[i];
109
110 printk(KERN_DEBUG "Did not find alt setting %u for intf %u, "
111 "config %u\n", alt_num, iface_num,
112 config->desc.bConfigurationValue);
113 return NULL;
114}
115EXPORT_SYMBOL_GPL(usb_find_alt_setting);
116
117/**
118 * usb_ifnum_to_if - get the interface object with a given interface number
119 * @dev: the device whose current configuration is considered
120 * @ifnum: the desired interface
121 *
122 * This walks the device descriptor for the currently active configuration
123 * to find the interface object with the particular interface number.
124 *
125 * Note that configuration descriptors are not required to assign interface
126 * numbers sequentially, so that it would be incorrect to assume that
127 * the first interface in that descriptor corresponds to interface zero.
128 * This routine helps device drivers avoid such mistakes.
129 * However, you should make sure that you do the right thing with any
130 * alternate settings available for this interfaces.
131 *
132 * Don't call this function unless you are bound to one of the interfaces
133 * on this device or you have locked the device!
134 *
135 * Return: A pointer to the interface that has @ifnum as interface number,
136 * if found. %NULL otherwise.
137 */
138struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
139 unsigned ifnum)
140{
141 struct usb_host_config *config = dev->actconfig;
142 int i;
143
144 if (!config)
145 return NULL;
146 for (i = 0; i < config->desc.bNumInterfaces; i++)
147 if (config->interface[i]->altsetting[0]
148 .desc.bInterfaceNumber == ifnum)
149 return config->interface[i];
150
151 return NULL;
152}
153EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
154
155/**
156 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
157 * @intf: the interface containing the altsetting in question
158 * @altnum: the desired alternate setting number
159 *
160 * This searches the altsetting array of the specified interface for
161 * an entry with the correct bAlternateSetting value.
162 *
163 * Note that altsettings need not be stored sequentially by number, so
164 * it would be incorrect to assume that the first altsetting entry in
165 * the array corresponds to altsetting zero. This routine helps device
166 * drivers avoid such mistakes.
167 *
168 * Don't call this function unless you are bound to the intf interface
169 * or you have locked the device!
170 *
171 * Return: A pointer to the entry of the altsetting array of @intf that
172 * has @altnum as the alternate setting number. %NULL if not found.
173 */
174struct usb_host_interface *usb_altnum_to_altsetting(
175 const struct usb_interface *intf,
176 unsigned int altnum)
177{
178 int i;
179
180 for (i = 0; i < intf->num_altsetting; i++) {
181 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
182 return &intf->altsetting[i];
183 }
184 return NULL;
185}
186EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
187
188struct find_interface_arg {
189 int minor;
190 struct device_driver *drv;
191};
192
193static int __find_interface(struct device *dev, void *data)
194{
195 struct find_interface_arg *arg = data;
196 struct usb_interface *intf;
197
198 if (!is_usb_interface(dev))
199 return 0;
200
201 if (dev->driver != arg->drv)
202 return 0;
203 intf = to_usb_interface(dev);
204 return intf->minor == arg->minor;
205}
206
207/**
208 * usb_find_interface - find usb_interface pointer for driver and device
209 * @drv: the driver whose current configuration is considered
210 * @minor: the minor number of the desired device
211 *
212 * This walks the bus device list and returns a pointer to the interface
213 * with the matching minor and driver. Note, this only works for devices
214 * that share the USB major number.
215 *
216 * Return: A pointer to the interface with the matching major and @minor.
217 */
218struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
219{
220 struct find_interface_arg argb;
221 struct device *dev;
222
223 argb.minor = minor;
224 argb.drv = &drv->drvwrap.driver;
225
226 dev = bus_find_device(&usb_bus_type, NULL, &argb, __find_interface);
227
228 /* Drop reference count from bus_find_device */
229 put_device(dev);
230
231 return dev ? to_usb_interface(dev) : NULL;
232}
233EXPORT_SYMBOL_GPL(usb_find_interface);
234
235struct each_dev_arg {
236 void *data;
237 int (*fn)(struct usb_device *, void *);
238};
239
240static int __each_dev(struct device *dev, void *data)
241{
242 struct each_dev_arg *arg = (struct each_dev_arg *)data;
243
244 /* There are struct usb_interface on the same bus, filter them out */
245 if (!is_usb_device(dev))
246 return 0;
247
248 return arg->fn(to_usb_device(dev), arg->data);
249}
250
251/**
252 * usb_for_each_dev - iterate over all USB devices in the system
253 * @data: data pointer that will be handed to the callback function
254 * @fn: callback function to be called for each USB device
255 *
256 * Iterate over all USB devices and call @fn for each, passing it @data. If it
257 * returns anything other than 0, we break the iteration prematurely and return
258 * that value.
259 */
260int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *))
261{
262 struct each_dev_arg arg = {data, fn};
263
264 return bus_for_each_dev(&usb_bus_type, NULL, &arg, __each_dev);
265}
266EXPORT_SYMBOL_GPL(usb_for_each_dev);
267
268/**
269 * usb_release_dev - free a usb device structure when all users of it are finished.
270 * @dev: device that's been disconnected
271 *
272 * Will be called only by the device core when all users of this usb device are
273 * done.
274 */
275static void usb_release_dev(struct device *dev)
276{
277 struct usb_device *udev;
278 struct usb_hcd *hcd;
279
280 udev = to_usb_device(dev);
281 hcd = bus_to_hcd(udev->bus);
282
283 usb_destroy_configuration(udev);
284 usb_release_bos_descriptor(udev);
285 usb_put_hcd(hcd);
286 kfree(udev->product);
287 kfree(udev->manufacturer);
288 kfree(udev->serial);
289 kfree(udev);
290}
291
292static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
293{
294 struct usb_device *usb_dev;
295
296 usb_dev = to_usb_device(dev);
297
298 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
299 return -ENOMEM;
300
301 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
302 return -ENOMEM;
303
304 return 0;
305}
306
307#ifdef CONFIG_PM
308
309/* USB device Power-Management thunks.
310 * There's no need to distinguish here between quiescing a USB device
311 * and powering it down; the generic_suspend() routine takes care of
312 * it by skipping the usb_port_suspend() call for a quiesce. And for
313 * USB interfaces there's no difference at all.
314 */
315
316static int usb_dev_prepare(struct device *dev)
317{
318 return 0; /* Implement eventually? */
319}
320
321static void usb_dev_complete(struct device *dev)
322{
323 /* Currently used only for rebinding interfaces */
324 usb_resume_complete(dev);
325}
326
327static int usb_dev_suspend(struct device *dev)
328{
329 return usb_suspend(dev, PMSG_SUSPEND);
330}
331
332static int usb_dev_resume(struct device *dev)
333{
334 return usb_resume(dev, PMSG_RESUME);
335}
336
337static int usb_dev_freeze(struct device *dev)
338{
339 return usb_suspend(dev, PMSG_FREEZE);
340}
341
342static int usb_dev_thaw(struct device *dev)
343{
344 return usb_resume(dev, PMSG_THAW);
345}
346
347static int usb_dev_poweroff(struct device *dev)
348{
349 return usb_suspend(dev, PMSG_HIBERNATE);
350}
351
352static int usb_dev_restore(struct device *dev)
353{
354 return usb_resume(dev, PMSG_RESTORE);
355}
356
357static const struct dev_pm_ops usb_device_pm_ops = {
358 .prepare = usb_dev_prepare,
359 .complete = usb_dev_complete,
360 .suspend = usb_dev_suspend,
361 .resume = usb_dev_resume,
362 .freeze = usb_dev_freeze,
363 .thaw = usb_dev_thaw,
364 .poweroff = usb_dev_poweroff,
365 .restore = usb_dev_restore,
366 .runtime_suspend = usb_runtime_suspend,
367 .runtime_resume = usb_runtime_resume,
368 .runtime_idle = usb_runtime_idle,
369};
370
371#endif /* CONFIG_PM */
372
373
374static char *usb_devnode(struct device *dev,
375 umode_t *mode, kuid_t *uid, kgid_t *gid)
376{
377 struct usb_device *usb_dev;
378
379 usb_dev = to_usb_device(dev);
380 return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
381 usb_dev->bus->busnum, usb_dev->devnum);
382}
383
384struct device_type usb_device_type = {
385 .name = "usb_device",
386 .release = usb_release_dev,
387 .uevent = usb_dev_uevent,
388 .devnode = usb_devnode,
389#ifdef CONFIG_PM
390 .pm = &usb_device_pm_ops,
391#endif
392};
393
394
395/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
396static unsigned usb_bus_is_wusb(struct usb_bus *bus)
397{
398 struct usb_hcd *hcd = bus_to_hcd(bus);
399 return hcd->wireless;
400}
401
402
403/**
404 * usb_alloc_dev - usb device constructor (usbcore-internal)
405 * @parent: hub to which device is connected; null to allocate a root hub
406 * @bus: bus used to access the device
407 * @port1: one-based index of port; ignored for root hubs
408 * Context: !in_interrupt()
409 *
410 * Only hub drivers (including virtual root hub drivers for host
411 * controllers) should ever call this.
412 *
413 * This call may not be used in a non-sleeping context.
414 *
415 * Return: On success, a pointer to the allocated usb device. %NULL on
416 * failure.
417 */
418struct usb_device *usb_alloc_dev(struct usb_device *parent,
419 struct usb_bus *bus, unsigned port1)
420{
421 struct usb_device *dev;
422 struct usb_hcd *usb_hcd = bus_to_hcd(bus);
423 unsigned root_hub = 0;
424 unsigned raw_port = port1;
425
426 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
427 if (!dev)
428 return NULL;
429
430 if (!usb_get_hcd(usb_hcd)) {
431 kfree(dev);
432 return NULL;
433 }
434 /* Root hubs aren't true devices, so don't allocate HCD resources */
435 if (usb_hcd->driver->alloc_dev && parent &&
436 !usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
437 usb_put_hcd(bus_to_hcd(bus));
438 kfree(dev);
439 return NULL;
440 }
441
442 device_initialize(&dev->dev);
443 dev->dev.bus = &usb_bus_type;
444 dev->dev.type = &usb_device_type;
445 dev->dev.groups = usb_device_groups;
446 /*
447 * Fake a dma_mask/offset for the USB device:
448 * We cannot really use the dma-mapping API (dma_alloc_* and
449 * dma_map_*) for USB devices but instead need to use
450 * usb_alloc_coherent and pass data in 'urb's, but some subsystems
451 * manually look into the mask/offset pair to determine whether
452 * they need bounce buffers.
453 * Note: calling dma_set_mask() on a USB device would set the
454 * mask for the entire HCD, so don't do that.
455 */
456 dev->dev.dma_mask = bus->controller->dma_mask;
457 dev->dev.dma_pfn_offset = bus->controller->dma_pfn_offset;
458 set_dev_node(&dev->dev, dev_to_node(bus->controller));
459 dev->state = USB_STATE_ATTACHED;
460 dev->lpm_disable_count = 1;
461 atomic_set(&dev->urbnum, 0);
462
463 INIT_LIST_HEAD(&dev->ep0.urb_list);
464 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
465 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
466 /* ep0 maxpacket comes later, from device descriptor */
467 usb_enable_endpoint(dev, &dev->ep0, false);
468 dev->can_submit = 1;
469
470 /* Save readable and stable topology id, distinguishing devices
471 * by location for diagnostics, tools, driver model, etc. The
472 * string is a path along hub ports, from the root. Each device's
473 * dev->devpath will be stable until USB is re-cabled, and hubs
474 * are often labeled with these port numbers. The name isn't
475 * as stable: bus->busnum changes easily from modprobe order,
476 * cardbus or pci hotplugging, and so on.
477 */
478 if (unlikely(!parent)) {
479 dev->devpath[0] = '0';
480 dev->route = 0;
481
482 dev->dev.parent = bus->controller;
483 dev_set_name(&dev->dev, "usb%d", bus->busnum);
484 root_hub = 1;
485 } else {
486 /* match any labeling on the hubs; it's one-based */
487 if (parent->devpath[0] == '0') {
488 snprintf(dev->devpath, sizeof dev->devpath,
489 "%d", port1);
490 /* Root ports are not counted in route string */
491 dev->route = 0;
492 } else {
493 snprintf(dev->devpath, sizeof dev->devpath,
494 "%s.%d", parent->devpath, port1);
495 /* Route string assumes hubs have less than 16 ports */
496 if (port1 < 15)
497 dev->route = parent->route +
498 (port1 << ((parent->level - 1)*4));
499 else
500 dev->route = parent->route +
501 (15 << ((parent->level - 1)*4));
502 }
503
504 dev->dev.parent = &parent->dev;
505 dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
506
507 if (!parent->parent) {
508 /* device under root hub's port */
509 raw_port = usb_hcd_find_raw_port_number(usb_hcd,
510 port1);
511 }
512 dev->dev.of_node = usb_of_get_child_node(parent->dev.of_node,
513 raw_port);
514
515 /* hub driver sets up TT records */
516 }
517
518 dev->portnum = port1;
519 dev->bus = bus;
520 dev->parent = parent;
521 INIT_LIST_HEAD(&dev->filelist);
522
523#ifdef CONFIG_PM
524 pm_runtime_set_autosuspend_delay(&dev->dev,
525 usb_autosuspend_delay * 1000);
526 dev->connect_time = jiffies;
527 dev->active_duration = -jiffies;
528#endif
529 if (root_hub) /* Root hub always ok [and always wired] */
530 dev->authorized = 1;
531 else {
532 dev->authorized = !!HCD_DEV_AUTHORIZED(usb_hcd);
533 dev->wusb = usb_bus_is_wusb(bus) ? 1 : 0;
534 }
535 return dev;
536}
537EXPORT_SYMBOL_GPL(usb_alloc_dev);
538
539/**
540 * usb_get_dev - increments the reference count of the usb device structure
541 * @dev: the device being referenced
542 *
543 * Each live reference to a device should 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_dev(), in their disconnect() methods.
548 *
549 * Return: A pointer to the device with the incremented reference counter.
550 */
551struct usb_device *usb_get_dev(struct usb_device *dev)
552{
553 if (dev)
554 get_device(&dev->dev);
555 return dev;
556}
557EXPORT_SYMBOL_GPL(usb_get_dev);
558
559/**
560 * usb_put_dev - release a use of the usb device structure
561 * @dev: device that's been disconnected
562 *
563 * Must be called when a user of a device is finished with it. When the last
564 * user of the device calls this function, the memory of the device is freed.
565 */
566void usb_put_dev(struct usb_device *dev)
567{
568 if (dev)
569 put_device(&dev->dev);
570}
571EXPORT_SYMBOL_GPL(usb_put_dev);
572
573/**
574 * usb_get_intf - increments the reference count of the usb interface structure
575 * @intf: the interface being referenced
576 *
577 * Each live reference to a interface must be refcounted.
578 *
579 * Drivers for USB interfaces should normally record such references in
580 * their probe() methods, when they bind to an interface, and release
581 * them by calling usb_put_intf(), in their disconnect() methods.
582 *
583 * Return: A pointer to the interface with the incremented reference counter.
584 */
585struct usb_interface *usb_get_intf(struct usb_interface *intf)
586{
587 if (intf)
588 get_device(&intf->dev);
589 return intf;
590}
591EXPORT_SYMBOL_GPL(usb_get_intf);
592
593/**
594 * usb_put_intf - release a use of the usb interface structure
595 * @intf: interface that's been decremented
596 *
597 * Must be called when a user of an interface is finished with it. When the
598 * last user of the interface calls this function, the memory of the interface
599 * is freed.
600 */
601void usb_put_intf(struct usb_interface *intf)
602{
603 if (intf)
604 put_device(&intf->dev);
605}
606EXPORT_SYMBOL_GPL(usb_put_intf);
607
608/* USB device locking
609 *
610 * USB devices and interfaces are locked using the semaphore in their
611 * embedded struct device. The hub driver guarantees that whenever a
612 * device is connected or disconnected, drivers are called with the
613 * USB device locked as well as their particular interface.
614 *
615 * Complications arise when several devices are to be locked at the same
616 * time. Only hub-aware drivers that are part of usbcore ever have to
617 * do this; nobody else needs to worry about it. The rule for locking
618 * is simple:
619 *
620 * When locking both a device and its parent, always lock the
621 * the parent first.
622 */
623
624/**
625 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
626 * @udev: device that's being locked
627 * @iface: interface bound to the driver making the request (optional)
628 *
629 * Attempts to acquire the device lock, but fails if the device is
630 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
631 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
632 * lock, the routine polls repeatedly. This is to prevent deadlock with
633 * disconnect; in some drivers (such as usb-storage) the disconnect()
634 * or suspend() method will block waiting for a device reset to complete.
635 *
636 * Return: A negative error code for failure, otherwise 0.
637 */
638int usb_lock_device_for_reset(struct usb_device *udev,
639 const struct usb_interface *iface)
640{
641 unsigned long jiffies_expire = jiffies + HZ;
642
643 if (udev->state == USB_STATE_NOTATTACHED)
644 return -ENODEV;
645 if (udev->state == USB_STATE_SUSPENDED)
646 return -EHOSTUNREACH;
647 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
648 iface->condition == USB_INTERFACE_UNBOUND))
649 return -EINTR;
650
651 while (!usb_trylock_device(udev)) {
652
653 /* If we can't acquire the lock after waiting one second,
654 * we're probably deadlocked */
655 if (time_after(jiffies, jiffies_expire))
656 return -EBUSY;
657
658 msleep(15);
659 if (udev->state == USB_STATE_NOTATTACHED)
660 return -ENODEV;
661 if (udev->state == USB_STATE_SUSPENDED)
662 return -EHOSTUNREACH;
663 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
664 iface->condition == USB_INTERFACE_UNBOUND))
665 return -EINTR;
666 }
667 return 0;
668}
669EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
670
671/**
672 * usb_get_current_frame_number - return current bus frame number
673 * @dev: the device whose bus is being queried
674 *
675 * Return: The current frame number for the USB host controller used
676 * with the given USB device. This can be used when scheduling
677 * isochronous requests.
678 *
679 * Note: Different kinds of host controller have different "scheduling
680 * horizons". While one type might support scheduling only 32 frames
681 * into the future, others could support scheduling up to 1024 frames
682 * into the future.
683 *
684 */
685int usb_get_current_frame_number(struct usb_device *dev)
686{
687 return usb_hcd_get_frame_number(dev);
688}
689EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
690
691/*-------------------------------------------------------------------*/
692/*
693 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
694 * extra field of the interface and endpoint descriptor structs.
695 */
696
697int __usb_get_extra_descriptor(char *buffer, unsigned size,
698 unsigned char type, void **ptr)
699{
700 struct usb_descriptor_header *header;
701
702 while (size >= sizeof(struct usb_descriptor_header)) {
703 header = (struct usb_descriptor_header *)buffer;
704
705 if (header->bLength < 2) {
706 printk(KERN_ERR
707 "%s: bogus descriptor, type %d length %d\n",
708 usbcore_name,
709 header->bDescriptorType,
710 header->bLength);
711 return -1;
712 }
713
714 if (header->bDescriptorType == type) {
715 *ptr = header;
716 return 0;
717 }
718
719 buffer += header->bLength;
720 size -= header->bLength;
721 }
722 return -1;
723}
724EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
725
726/**
727 * usb_alloc_coherent - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
728 * @dev: device the buffer will be used with
729 * @size: requested buffer size
730 * @mem_flags: affect whether allocation may block
731 * @dma: used to return DMA address of buffer
732 *
733 * Return: Either null (indicating no buffer could be allocated), or the
734 * cpu-space pointer to a buffer that may be used to perform DMA to the
735 * specified device. Such cpu-space buffers are returned along with the DMA
736 * address (through the pointer provided).
737 *
738 * Note:
739 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
740 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
741 * hardware during URB completion/resubmit. The implementation varies between
742 * platforms, depending on details of how DMA will work to this device.
743 * Using these buffers also eliminates cacheline sharing problems on
744 * architectures where CPU caches are not DMA-coherent. On systems without
745 * bus-snooping caches, these buffers are uncached.
746 *
747 * When the buffer is no longer used, free it with usb_free_coherent().
748 */
749void *usb_alloc_coherent(struct usb_device *dev, size_t size, gfp_t mem_flags,
750 dma_addr_t *dma)
751{
752 if (!dev || !dev->bus)
753 return NULL;
754 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
755}
756EXPORT_SYMBOL_GPL(usb_alloc_coherent);
757
758/**
759 * usb_free_coherent - free memory allocated with usb_alloc_coherent()
760 * @dev: device the buffer was used with
761 * @size: requested buffer size
762 * @addr: CPU address of buffer
763 * @dma: DMA address of buffer
764 *
765 * This reclaims an I/O buffer, letting it be reused. The memory must have
766 * been allocated using usb_alloc_coherent(), and the parameters must match
767 * those provided in that allocation request.
768 */
769void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
770 dma_addr_t dma)
771{
772 if (!dev || !dev->bus)
773 return;
774 if (!addr)
775 return;
776 hcd_buffer_free(dev->bus, size, addr, dma);
777}
778EXPORT_SYMBOL_GPL(usb_free_coherent);
779
780/**
781 * usb_buffer_map - create DMA mapping(s) for an urb
782 * @urb: urb whose transfer_buffer/setup_packet will be mapped
783 *
784 * URB_NO_TRANSFER_DMA_MAP is added to urb->transfer_flags if the operation
785 * succeeds. If the device is connected to this system through a non-DMA
786 * controller, this operation always succeeds.
787 *
788 * This call would normally be used for an urb which is reused, perhaps
789 * as the target of a large periodic transfer, with usb_buffer_dmasync()
790 * calls to synchronize memory and dma state.
791 *
792 * Reverse the effect of this call with usb_buffer_unmap().
793 *
794 * Return: Either %NULL (indicating no buffer could be mapped), or @urb.
795 *
796 */
797#if 0
798struct urb *usb_buffer_map(struct urb *urb)
799{
800 struct usb_bus *bus;
801 struct device *controller;
802
803 if (!urb
804 || !urb->dev
805 || !(bus = urb->dev->bus)
806 || !(controller = bus->controller))
807 return NULL;
808
809 if (controller->dma_mask) {
810 urb->transfer_dma = dma_map_single(controller,
811 urb->transfer_buffer, urb->transfer_buffer_length,
812 usb_pipein(urb->pipe)
813 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
814 /* FIXME generic api broken like pci, can't report errors */
815 /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
816 } else
817 urb->transfer_dma = ~0;
818 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
819 return urb;
820}
821EXPORT_SYMBOL_GPL(usb_buffer_map);
822#endif /* 0 */
823
824/* XXX DISABLED, no users currently. If you wish to re-enable this
825 * XXX please determine whether the sync is to transfer ownership of
826 * XXX the buffer from device to cpu or vice verse, and thusly use the
827 * XXX appropriate _for_{cpu,device}() method. -DaveM
828 */
829#if 0
830
831/**
832 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
833 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
834 */
835void usb_buffer_dmasync(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_sync_single_for_cpu(controller,
849 urb->transfer_dma, urb->transfer_buffer_length,
850 usb_pipein(urb->pipe)
851 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
852 if (usb_pipecontrol(urb->pipe))
853 dma_sync_single_for_cpu(controller,
854 urb->setup_dma,
855 sizeof(struct usb_ctrlrequest),
856 DMA_TO_DEVICE);
857 }
858}
859EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
860#endif
861
862/**
863 * usb_buffer_unmap - free DMA mapping(s) for an urb
864 * @urb: urb whose transfer_buffer will be unmapped
865 *
866 * Reverses the effect of usb_buffer_map().
867 */
868#if 0
869void usb_buffer_unmap(struct urb *urb)
870{
871 struct usb_bus *bus;
872 struct device *controller;
873
874 if (!urb
875 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
876 || !urb->dev
877 || !(bus = urb->dev->bus)
878 || !(controller = bus->controller))
879 return;
880
881 if (controller->dma_mask) {
882 dma_unmap_single(controller,
883 urb->transfer_dma, urb->transfer_buffer_length,
884 usb_pipein(urb->pipe)
885 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
886 }
887 urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
888}
889EXPORT_SYMBOL_GPL(usb_buffer_unmap);
890#endif /* 0 */
891
892#if 0
893/**
894 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
895 * @dev: device to which the scatterlist will be mapped
896 * @is_in: mapping transfer direction
897 * @sg: the scatterlist to map
898 * @nents: the number of entries in the scatterlist
899 *
900 * Return: Either < 0 (indicating no buffers could be mapped), or the
901 * number of DMA mapping array entries in the scatterlist.
902 *
903 * Note:
904 * The caller is responsible for placing the resulting DMA addresses from
905 * the scatterlist into URB transfer buffer pointers, and for setting the
906 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
907 *
908 * Top I/O rates come from queuing URBs, instead of waiting for each one
909 * to complete before starting the next I/O. This is particularly easy
910 * to do with scatterlists. Just allocate and submit one URB for each DMA
911 * mapping entry returned, stopping on the first error or when all succeed.
912 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
913 *
914 * This call would normally be used when translating scatterlist requests,
915 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
916 * may be able to coalesce mappings for improved I/O efficiency.
917 *
918 * Reverse the effect of this call with usb_buffer_unmap_sg().
919 */
920int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
921 struct scatterlist *sg, int nents)
922{
923 struct usb_bus *bus;
924 struct device *controller;
925
926 if (!dev
927 || !(bus = dev->bus)
928 || !(controller = bus->controller)
929 || !controller->dma_mask)
930 return -EINVAL;
931
932 /* FIXME generic api broken like pci, can't report errors */
933 return dma_map_sg(controller, sg, nents,
934 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
935}
936EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
937#endif
938
939/* XXX DISABLED, no users currently. If you wish to re-enable this
940 * XXX please determine whether the sync is to transfer ownership of
941 * XXX the buffer from device to cpu or vice verse, and thusly use the
942 * XXX appropriate _for_{cpu,device}() method. -DaveM
943 */
944#if 0
945
946/**
947 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
948 * @dev: device to which the scatterlist will be mapped
949 * @is_in: mapping transfer direction
950 * @sg: the scatterlist to synchronize
951 * @n_hw_ents: the positive return value from usb_buffer_map_sg
952 *
953 * Use this when you are re-using a scatterlist's data buffers for
954 * another USB request.
955 */
956void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
957 struct scatterlist *sg, int n_hw_ents)
958{
959 struct usb_bus *bus;
960 struct device *controller;
961
962 if (!dev
963 || !(bus = dev->bus)
964 || !(controller = bus->controller)
965 || !controller->dma_mask)
966 return;
967
968 dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
969 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
970}
971EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
972#endif
973
974#if 0
975/**
976 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
977 * @dev: device to which the scatterlist will be mapped
978 * @is_in: mapping transfer direction
979 * @sg: the scatterlist to unmap
980 * @n_hw_ents: the positive return value from usb_buffer_map_sg
981 *
982 * Reverses the effect of usb_buffer_map_sg().
983 */
984void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
985 struct scatterlist *sg, int n_hw_ents)
986{
987 struct usb_bus *bus;
988 struct device *controller;
989
990 if (!dev
991 || !(bus = dev->bus)
992 || !(controller = bus->controller)
993 || !controller->dma_mask)
994 return;
995
996 dma_unmap_sg(controller, sg, n_hw_ents,
997 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
998}
999EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
1000#endif
1001
1002/*
1003 * Notifications of device and interface registration
1004 */
1005static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
1006 void *data)
1007{
1008 struct device *dev = data;
1009
1010 switch (action) {
1011 case BUS_NOTIFY_ADD_DEVICE:
1012 if (dev->type == &usb_device_type)
1013 (void) usb_create_sysfs_dev_files(to_usb_device(dev));
1014 else if (dev->type == &usb_if_device_type)
1015 usb_create_sysfs_intf_files(to_usb_interface(dev));
1016 break;
1017
1018 case BUS_NOTIFY_DEL_DEVICE:
1019 if (dev->type == &usb_device_type)
1020 usb_remove_sysfs_dev_files(to_usb_device(dev));
1021 else if (dev->type == &usb_if_device_type)
1022 usb_remove_sysfs_intf_files(to_usb_interface(dev));
1023 break;
1024 }
1025 return 0;
1026}
1027
1028static struct notifier_block usb_bus_nb = {
1029 .notifier_call = usb_bus_notify,
1030};
1031
1032struct dentry *usb_debug_root;
1033EXPORT_SYMBOL_GPL(usb_debug_root);
1034
1035static struct dentry *usb_debug_devices;
1036
1037static int usb_debugfs_init(void)
1038{
1039 usb_debug_root = debugfs_create_dir("usb", NULL);
1040 if (!usb_debug_root)
1041 return -ENOENT;
1042
1043 usb_debug_devices = debugfs_create_file("devices", 0444,
1044 usb_debug_root, NULL,
1045 &usbfs_devices_fops);
1046 if (!usb_debug_devices) {
1047 debugfs_remove(usb_debug_root);
1048 usb_debug_root = NULL;
1049 return -ENOENT;
1050 }
1051
1052 return 0;
1053}
1054
1055static void usb_debugfs_cleanup(void)
1056{
1057 debugfs_remove(usb_debug_devices);
1058 debugfs_remove(usb_debug_root);
1059}
1060
1061/*
1062 * Init
1063 */
1064static int __init usb_init(void)
1065{
1066 int retval;
1067 if (usb_disabled()) {
1068 pr_info("%s: USB support disabled\n", usbcore_name);
1069 return 0;
1070 }
1071 usb_init_pool_max();
1072
1073 retval = usb_debugfs_init();
1074 if (retval)
1075 goto out;
1076
1077 usb_acpi_register();
1078 retval = bus_register(&usb_bus_type);
1079 if (retval)
1080 goto bus_register_failed;
1081 retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
1082 if (retval)
1083 goto bus_notifier_failed;
1084 retval = usb_major_init();
1085 if (retval)
1086 goto major_init_failed;
1087 retval = usb_register(&usbfs_driver);
1088 if (retval)
1089 goto driver_register_failed;
1090 retval = usb_devio_init();
1091 if (retval)
1092 goto usb_devio_init_failed;
1093 retval = usb_hub_init();
1094 if (retval)
1095 goto hub_init_failed;
1096 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
1097 if (!retval)
1098 goto out;
1099
1100 usb_hub_cleanup();
1101hub_init_failed:
1102 usb_devio_cleanup();
1103usb_devio_init_failed:
1104 usb_deregister(&usbfs_driver);
1105driver_register_failed:
1106 usb_major_cleanup();
1107major_init_failed:
1108 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1109bus_notifier_failed:
1110 bus_unregister(&usb_bus_type);
1111bus_register_failed:
1112 usb_acpi_unregister();
1113 usb_debugfs_cleanup();
1114out:
1115 return retval;
1116}
1117
1118/*
1119 * Cleanup
1120 */
1121static void __exit usb_exit(void)
1122{
1123 /* This will matter if shutdown/reboot does exitcalls. */
1124 if (usb_disabled())
1125 return;
1126
1127 usb_deregister_device_driver(&usb_generic_driver);
1128 usb_major_cleanup();
1129 usb_deregister(&usbfs_driver);
1130 usb_devio_cleanup();
1131 usb_hub_cleanup();
1132 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1133 bus_unregister(&usb_bus_type);
1134 usb_acpi_unregister();
1135 usb_debugfs_cleanup();
1136 idr_destroy(&usb_bus_idr);
1137}
1138
1139subsys_initcall(usb_init);
1140module_exit(usb_exit);
1141MODULE_LICENSE("GPL");