blob: 138252e0a1cfdb20e20b1d80c67fffa75186665d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Uwe Zeisbergerf30c2262006-10-03 23:01:26 +02002 * drivers/usb/core/usb.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * (C) Copyright Linus Torvalds 1999
5 * (C) Copyright Johannes Erdfelt 1999-2001
6 * (C) Copyright Andreas Gal 1999
7 * (C) Copyright Gregory P. Smith 1999
8 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9 * (C) Copyright Randy Dunlap 2000
10 * (C) Copyright David Brownell 2000-2004
11 * (C) Copyright Yggdrasil Computing, Inc. 2000
12 * (usb_device_id matching changes by Adam J. Richter)
13 * (C) Copyright Greg Kroah-Hartman 2002-2003
14 *
15 * NOTE! This is not actually a driver at all, rather this is
16 * just a collection of helper routines that implement the
17 * generic USB things that the real drivers can use..
18 *
19 * Think of this as a "USB library" rather than anything else.
20 * It should be considered a slave, with no callbacks. Callbacks
21 * are evil.
22 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/module.h>
Alan Sternb5e795f2007-02-20 15:00:53 -050025#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/string.h>
27#include <linux/bitops.h>
28#include <linux/slab.h>
29#include <linux/interrupt.h> /* for in_interrupt() */
30#include <linux/kmod.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <linux/errno.h>
34#include <linux/smp_lock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <linux/usb.h>
Arjan van de Ven4186ecf2006-01-11 15:55:29 +010036#include <linux/mutex.h>
Alan Sternbd859282006-09-19 10:14:07 -040037#include <linux/workqueue.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <asm/io.h>
40#include <asm/scatterlist.h>
41#include <linux/mm.h>
42#include <linux/dma-mapping.h>
43
44#include "hcd.h"
45#include "usb.h"
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48const char *usbcore_name = "usbcore";
49
50static int nousb; /* Disable USB when built into kernel image */
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Alan Stern6b157c92007-03-13 16:37:30 -040052/* Workqueue for autosuspend and for remote wakeup of root hubs */
53struct workqueue_struct *ksuspend_usb_wq;
Alan Sternbd859282006-09-19 10:14:07 -040054
Alan Sternb5e795f2007-02-20 15:00:53 -050055#ifdef CONFIG_USB_SUSPEND
56static int usb_autosuspend_delay = 2; /* Default delay value,
57 * in seconds */
58module_param_named(autosuspend, usb_autosuspend_delay, uint, 0644);
59MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
60
61#else
62#define usb_autosuspend_delay 0
63#endif
64
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Linus Torvalds1da177e2005-04-16 15:20:36 -070066/**
67 * usb_ifnum_to_if - get the interface object with a given interface number
68 * @dev: the device whose current configuration is considered
69 * @ifnum: the desired interface
70 *
71 * This walks the device descriptor for the currently active configuration
72 * and returns a pointer to the interface with that particular interface
73 * number, or null.
74 *
75 * Note that configuration descriptors are not required to assign interface
76 * numbers sequentially, so that it would be incorrect to assume that
77 * the first interface in that descriptor corresponds to interface zero.
78 * This routine helps device drivers avoid such mistakes.
79 * However, you should make sure that you do the right thing with any
80 * alternate settings available for this interfaces.
81 *
82 * Don't call this function unless you are bound to one of the interfaces
83 * on this device or you have locked the device!
84 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -030085struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
86 unsigned ifnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
88 struct usb_host_config *config = dev->actconfig;
89 int i;
90
91 if (!config)
92 return NULL;
93 for (i = 0; i < config->desc.bNumInterfaces; i++)
94 if (config->interface[i]->altsetting[0]
95 .desc.bInterfaceNumber == ifnum)
96 return config->interface[i];
97
98 return NULL;
99}
100
101/**
102 * usb_altnum_to_altsetting - get the altsetting structure with a given
103 * alternate setting number.
104 * @intf: the interface containing the altsetting in question
105 * @altnum: the desired alternate setting number
106 *
107 * This searches the altsetting array of the specified interface for
108 * an entry with the correct bAlternateSetting value and returns a pointer
109 * to that entry, or null.
110 *
111 * Note that altsettings need not be stored sequentially by number, so
112 * it would be incorrect to assume that the first altsetting entry in
113 * the array corresponds to altsetting zero. This routine helps device
114 * drivers avoid such mistakes.
115 *
116 * Don't call this function unless you are bound to the intf interface
117 * or you have locked the device!
118 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300119struct usb_host_interface *usb_altnum_to_altsetting(const struct usb_interface *intf,
120 unsigned int altnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121{
122 int i;
123
124 for (i = 0; i < intf->num_altsetting; i++) {
125 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
126 return &intf->altsetting[i];
127 }
128 return NULL;
129}
130
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800131struct find_interface_arg {
132 int minor;
133 struct usb_interface *interface;
134};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800136static int __find_interface(struct device * dev, void * data)
137{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800138 struct find_interface_arg *arg = data;
139 struct usb_interface *intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800140
141 /* can't look at usb devices, only interfaces */
Alan Stern8bb54ab2006-07-01 22:08:49 -0400142 if (is_usb_device(dev))
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800143 return 0;
144
145 intf = to_usb_interface(dev);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800146 if (intf->minor != -1 && intf->minor == arg->minor) {
147 arg->interface = intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800148 return 1;
149 }
150 return 0;
151}
152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153/**
154 * usb_find_interface - find usb_interface pointer for driver and device
155 * @drv: the driver whose current configuration is considered
156 * @minor: the minor number of the desired device
157 *
158 * This walks the driver device list and returns a pointer to the interface
159 * with the matching minor. Note, this only works for devices that share the
160 * USB major number.
161 */
162struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
163{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800164 struct find_interface_arg argb;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700165 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800167 argb.minor = minor;
168 argb.interface = NULL;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700169 /* eat the error, it will be in argb.interface */
170 retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb,
171 __find_interface);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800172 return argb.interface;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173}
174
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175/**
176 * usb_release_dev - free a usb device structure when all users of it are finished.
177 * @dev: device that's been disconnected
178 *
179 * Will be called only by the device core when all users of this usb device are
180 * done.
181 */
182static void usb_release_dev(struct device *dev)
183{
184 struct usb_device *udev;
185
186 udev = to_usb_device(dev);
187
Alan Sternbd859282006-09-19 10:14:07 -0400188#ifdef CONFIG_USB_SUSPEND
Alan Stern645daaa2006-08-30 15:47:02 -0400189 cancel_delayed_work(&udev->autosuspend);
Alan Sternbd859282006-09-19 10:14:07 -0400190 flush_workqueue(ksuspend_usb_wq);
Alan Stern645daaa2006-08-30 15:47:02 -0400191#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 usb_destroy_configuration(udev);
Alan Stern17200582006-08-30 11:32:52 -0400193 usb_put_hcd(bus_to_hcd(udev->bus));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 kfree(udev->product);
195 kfree(udev->manufacturer);
196 kfree(udev->serial);
197 kfree(udev);
198}
199
Alan Stern645daaa2006-08-30 15:47:02 -0400200#ifdef CONFIG_PM
201
Alan Sternbd859282006-09-19 10:14:07 -0400202static int ksuspend_usb_init(void)
203{
204 ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd");
205 if (!ksuspend_usb_wq)
206 return -ENOMEM;
207 return 0;
208}
209
210static void ksuspend_usb_cleanup(void)
211{
212 destroy_workqueue(ksuspend_usb_wq);
213}
214
Alan Sterndb063502006-11-13 15:02:04 -0500215#else
216
217#define ksuspend_usb_init() 0
218#define ksuspend_usb_cleanup() do {} while (0)
219
220#endif /* CONFIG_PM */
Alan Stern645daaa2006-08-30 15:47:02 -0400221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222/**
223 * usb_alloc_dev - usb device constructor (usbcore-internal)
224 * @parent: hub to which device is connected; null to allocate a root hub
225 * @bus: bus used to access the device
226 * @port1: one-based index of port; ignored for root hubs
Oliver Neukum92516442007-01-23 15:55:28 -0500227 * Context: !in_interrupt()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 *
229 * Only hub drivers (including virtual root hub drivers for host
230 * controllers) should ever call this.
231 *
232 * This call may not be used in a non-sleeping context.
233 */
234struct usb_device *
235usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
236{
237 struct usb_device *dev;
238
Alan Stern0a1ef3b2005-10-24 15:38:24 -0400239 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 if (!dev)
241 return NULL;
242
Alan Stern17200582006-08-30 11:32:52 -0400243 if (!usb_get_hcd(bus_to_hcd(bus))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 kfree(dev);
245 return NULL;
246 }
247
248 device_initialize(&dev->dev);
249 dev->dev.bus = &usb_bus_type;
250 dev->dev.dma_mask = bus->controller->dma_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 dev->dev.release = usb_release_dev;
252 dev->state = USB_STATE_ATTACHED;
253
Alan Stern8bb54ab2006-07-01 22:08:49 -0400254 /* This magic assignment distinguishes devices from interfaces */
255 dev->dev.platform_data = &usb_generic_driver;
256
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 INIT_LIST_HEAD(&dev->ep0.urb_list);
258 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
259 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
260 /* ep0 maxpacket comes later, from device descriptor */
261 dev->ep_in[0] = dev->ep_out[0] = &dev->ep0;
262
263 /* Save readable and stable topology id, distinguishing devices
264 * by location for diagnostics, tools, driver model, etc. The
265 * string is a path along hub ports, from the root. Each device's
266 * dev->devpath will be stable until USB is re-cabled, and hubs
267 * are often labeled with these port numbers. The bus_id isn't
268 * as stable: bus->busnum changes easily from modprobe order,
269 * cardbus or pci hotplugging, and so on.
270 */
Oliver Neukum92516442007-01-23 15:55:28 -0500271 if (unlikely(!parent)) {
272 dev->devpath[0] = '0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
274 dev->dev.parent = bus->controller;
Oliver Neukum92516442007-01-23 15:55:28 -0500275 sprintf(&dev->dev.bus_id[0], "usb%d", bus->busnum);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 } else {
277 /* match any labeling on the hubs; it's one-based */
Oliver Neukum92516442007-01-23 15:55:28 -0500278 if (parent->devpath[0] == '0')
279 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 "%d", port1);
281 else
Oliver Neukum92516442007-01-23 15:55:28 -0500282 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 "%s.%d", parent->devpath, port1);
284
285 dev->dev.parent = &parent->dev;
Oliver Neukum92516442007-01-23 15:55:28 -0500286 sprintf(&dev->dev.bus_id[0], "%d-%s",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 bus->busnum, dev->devpath);
288
289 /* hub driver sets up TT records */
290 }
291
Alan Stern12c3da32005-11-23 12:09:52 -0500292 dev->portnum = port1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 dev->bus = bus;
294 dev->parent = parent;
295 INIT_LIST_HEAD(&dev->filelist);
296
Alan Stern645daaa2006-08-30 15:47:02 -0400297#ifdef CONFIG_PM
298 mutex_init(&dev->pm_mutex);
David Howellsc4028952006-11-22 14:57:56 +0000299 INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
Alan Sternb5e795f2007-02-20 15:00:53 -0500300 dev->autosuspend_delay = usb_autosuspend_delay * HZ;
Alan Stern645daaa2006-08-30 15:47:02 -0400301#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 return dev;
303}
304
305/**
306 * usb_get_dev - increments the reference count of the usb device structure
307 * @dev: the device being referenced
308 *
309 * Each live reference to a device should be refcounted.
310 *
311 * Drivers for USB interfaces should normally record such references in
312 * their probe() methods, when they bind to an interface, and release
313 * them by calling usb_put_dev(), in their disconnect() methods.
314 *
315 * A pointer to the device with the incremented reference counter is returned.
316 */
317struct usb_device *usb_get_dev(struct usb_device *dev)
318{
319 if (dev)
320 get_device(&dev->dev);
321 return dev;
322}
323
324/**
325 * usb_put_dev - release a use of the usb device structure
326 * @dev: device that's been disconnected
327 *
328 * Must be called when a user of a device is finished with it. When the last
329 * user of the device calls this function, the memory of the device is freed.
330 */
331void usb_put_dev(struct usb_device *dev)
332{
333 if (dev)
334 put_device(&dev->dev);
335}
336
337/**
338 * usb_get_intf - increments the reference count of the usb interface structure
339 * @intf: the interface being referenced
340 *
341 * Each live reference to a interface must be refcounted.
342 *
343 * Drivers for USB interfaces should normally record such references in
344 * their probe() methods, when they bind to an interface, and release
345 * them by calling usb_put_intf(), in their disconnect() methods.
346 *
347 * A pointer to the interface with the incremented reference counter is
348 * returned.
349 */
350struct usb_interface *usb_get_intf(struct usb_interface *intf)
351{
352 if (intf)
353 get_device(&intf->dev);
354 return intf;
355}
356
357/**
358 * usb_put_intf - release a use of the usb interface structure
359 * @intf: interface that's been decremented
360 *
361 * Must be called when a user of an interface is finished with it. When the
362 * last user of the interface calls this function, the memory of the interface
363 * is freed.
364 */
365void usb_put_intf(struct usb_interface *intf)
366{
367 if (intf)
368 put_device(&intf->dev);
369}
370
371
372/* USB device locking
373 *
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500374 * USB devices and interfaces are locked using the semaphore in their
375 * embedded struct device. The hub driver guarantees that whenever a
376 * device is connected or disconnected, drivers are called with the
377 * USB device locked as well as their particular interface.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 *
379 * Complications arise when several devices are to be locked at the same
380 * time. Only hub-aware drivers that are part of usbcore ever have to
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500381 * do this; nobody else needs to worry about it. The rule for locking
382 * is simple:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 *
384 * When locking both a device and its parent, always lock the
385 * the parent first.
386 */
387
388/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 * usb_lock_device_for_reset - cautiously acquire the lock for a
390 * usb device structure
391 * @udev: device that's being locked
392 * @iface: interface bound to the driver making the request (optional)
393 *
394 * Attempts to acquire the device lock, but fails if the device is
395 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
396 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
397 * lock, the routine polls repeatedly. This is to prevent deadlock with
398 * disconnect; in some drivers (such as usb-storage) the disconnect()
Alan Stern3ea15962005-08-11 10:15:39 -0400399 * or suspend() method will block waiting for a device reset to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 *
401 * Returns a negative error code for failure, otherwise 1 or 0 to indicate
402 * that the device will or will not have to be unlocked. (0 can be
403 * returned when an interface is given and is BINDING, because in that
404 * case the driver already owns the device lock.)
405 */
406int usb_lock_device_for_reset(struct usb_device *udev,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300407 const struct usb_interface *iface)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408{
Alan Stern3ea15962005-08-11 10:15:39 -0400409 unsigned long jiffies_expire = jiffies + HZ;
410
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 if (udev->state == USB_STATE_NOTATTACHED)
412 return -ENODEV;
413 if (udev->state == USB_STATE_SUSPENDED)
414 return -EHOSTUNREACH;
415 if (iface) {
416 switch (iface->condition) {
417 case USB_INTERFACE_BINDING:
418 return 0;
419 case USB_INTERFACE_BOUND:
420 break;
421 default:
422 return -EINTR;
423 }
424 }
425
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500426 while (usb_trylock_device(udev) != 0) {
Alan Stern3ea15962005-08-11 10:15:39 -0400427
428 /* If we can't acquire the lock after waiting one second,
429 * we're probably deadlocked */
430 if (time_after(jiffies, jiffies_expire))
431 return -EBUSY;
432
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 msleep(15);
434 if (udev->state == USB_STATE_NOTATTACHED)
435 return -ENODEV;
436 if (udev->state == USB_STATE_SUSPENDED)
437 return -EHOSTUNREACH;
438 if (iface && iface->condition != USB_INTERFACE_BOUND)
439 return -EINTR;
440 }
441 return 1;
442}
443
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444
445static struct usb_device *match_device(struct usb_device *dev,
446 u16 vendor_id, u16 product_id)
447{
448 struct usb_device *ret_dev = NULL;
449 int child;
450
451 dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
452 le16_to_cpu(dev->descriptor.idVendor),
453 le16_to_cpu(dev->descriptor.idProduct));
454
455 /* see if this device matches */
456 if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
457 (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
Oliver Neukum92516442007-01-23 15:55:28 -0500458 dev_dbg(&dev->dev, "matched this device!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 ret_dev = usb_get_dev(dev);
460 goto exit;
461 }
462
463 /* look through all of the children of this device */
464 for (child = 0; child < dev->maxchild; ++child) {
465 if (dev->children[child]) {
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500466 usb_lock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 ret_dev = match_device(dev->children[child],
468 vendor_id, product_id);
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500469 usb_unlock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 if (ret_dev)
471 goto exit;
472 }
473 }
474exit:
475 return ret_dev;
476}
477
478/**
479 * usb_find_device - find a specific usb device in the system
480 * @vendor_id: the vendor id of the device to find
481 * @product_id: the product id of the device to find
482 *
483 * Returns a pointer to a struct usb_device if such a specified usb
484 * device is present in the system currently. The usage count of the
485 * device will be incremented if a device is found. Make sure to call
486 * usb_put_dev() when the caller is finished with the device.
487 *
488 * If a device with the specified vendor and product id is not found,
489 * NULL is returned.
490 */
491struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
492{
493 struct list_head *buslist;
494 struct usb_bus *bus;
495 struct usb_device *dev = NULL;
496
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100497 mutex_lock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 for (buslist = usb_bus_list.next;
499 buslist != &usb_bus_list;
500 buslist = buslist->next) {
501 bus = container_of(buslist, struct usb_bus, bus_list);
502 if (!bus->root_hub)
503 continue;
504 usb_lock_device(bus->root_hub);
505 dev = match_device(bus->root_hub, vendor_id, product_id);
506 usb_unlock_device(bus->root_hub);
507 if (dev)
508 goto exit;
509 }
510exit:
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100511 mutex_unlock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 return dev;
513}
514
515/**
516 * usb_get_current_frame_number - return current bus frame number
517 * @dev: the device whose bus is being queried
518 *
519 * Returns the current frame number for the USB host controller
520 * used with the given USB device. This can be used when scheduling
521 * isochronous requests.
522 *
523 * Note that different kinds of host controller have different
524 * "scheduling horizons". While one type might support scheduling only
525 * 32 frames into the future, others could support scheduling up to
526 * 1024 frames into the future.
527 */
528int usb_get_current_frame_number(struct usb_device *dev)
529{
Oliver Neukum92516442007-01-23 15:55:28 -0500530 return usb_hcd_get_frame_number(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531}
532
533/*-------------------------------------------------------------------*/
534/*
535 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
536 * extra field of the interface and endpoint descriptor structs.
537 */
538
539int __usb_get_extra_descriptor(char *buffer, unsigned size,
540 unsigned char type, void **ptr)
541{
542 struct usb_descriptor_header *header;
543
544 while (size >= sizeof(struct usb_descriptor_header)) {
545 header = (struct usb_descriptor_header *)buffer;
546
547 if (header->bLength < 2) {
548 printk(KERN_ERR
549 "%s: bogus descriptor, type %d length %d\n",
550 usbcore_name,
551 header->bDescriptorType,
552 header->bLength);
553 return -1;
554 }
555
556 if (header->bDescriptorType == type) {
557 *ptr = header;
558 return 0;
559 }
560
561 buffer += header->bLength;
562 size -= header->bLength;
563 }
564 return -1;
565}
566
567/**
568 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
569 * @dev: device the buffer will be used with
570 * @size: requested buffer size
571 * @mem_flags: affect whether allocation may block
572 * @dma: used to return DMA address of buffer
573 *
574 * Return value is either null (indicating no buffer could be allocated), or
575 * the cpu-space pointer to a buffer that may be used to perform DMA to the
576 * specified device. Such cpu-space buffers are returned along with the DMA
577 * address (through the pointer provided).
578 *
579 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
580 * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
581 * mapping hardware for long idle periods. The implementation varies between
582 * platforms, depending on details of how DMA will work to this device.
583 * Using these buffers also helps prevent cacheline sharing problems on
584 * architectures where CPU caches are not DMA-coherent.
585 *
586 * When the buffer is no longer used, free it with usb_buffer_free().
587 */
Oliver Neukum92516442007-01-23 15:55:28 -0500588void *usb_buffer_alloc(
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 struct usb_device *dev,
590 size_t size,
Al Viro55016f12005-10-21 03:21:58 -0400591 gfp_t mem_flags,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 dma_addr_t *dma
593)
594{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400595 if (!dev || !dev->bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 return NULL;
Oliver Neukum92516442007-01-23 15:55:28 -0500597 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598}
599
600/**
601 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
602 * @dev: device the buffer was used with
603 * @size: requested buffer size
604 * @addr: CPU address of buffer
605 * @dma: DMA address of buffer
606 *
607 * This reclaims an I/O buffer, letting it be reused. The memory must have
608 * been allocated using usb_buffer_alloc(), and the parameters must match
609 * those provided in that allocation request.
610 */
Oliver Neukum92516442007-01-23 15:55:28 -0500611void usb_buffer_free(
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 struct usb_device *dev,
613 size_t size,
614 void *addr,
615 dma_addr_t dma
616)
617{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400618 if (!dev || !dev->bus)
Dmitry Torokhovb94badb2006-08-01 22:33:34 -0400619 return;
620 if (!addr)
621 return;
Oliver Neukum92516442007-01-23 15:55:28 -0500622 hcd_buffer_free(dev->bus, size, addr, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623}
624
625/**
626 * usb_buffer_map - create DMA mapping(s) for an urb
627 * @urb: urb whose transfer_buffer/setup_packet will be mapped
628 *
629 * Return value is either null (indicating no buffer could be mapped), or
630 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
631 * added to urb->transfer_flags if the operation succeeds. If the device
632 * is connected to this system through a non-DMA controller, this operation
633 * always succeeds.
634 *
635 * This call would normally be used for an urb which is reused, perhaps
636 * as the target of a large periodic transfer, with usb_buffer_dmasync()
637 * calls to synchronize memory and dma state.
638 *
639 * Reverse the effect of this call with usb_buffer_unmap().
640 */
641#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500642struct urb *usb_buffer_map(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643{
644 struct usb_bus *bus;
645 struct device *controller;
646
647 if (!urb
648 || !urb->dev
649 || !(bus = urb->dev->bus)
650 || !(controller = bus->controller))
651 return NULL;
652
653 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500654 urb->transfer_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 urb->transfer_buffer, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500656 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500658 if (usb_pipecontrol(urb->pipe))
659 urb->setup_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 urb->setup_packet,
Oliver Neukum92516442007-01-23 15:55:28 -0500661 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 DMA_TO_DEVICE);
663 // FIXME generic api broken like pci, can't report errors
664 // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
665 } else
666 urb->transfer_dma = ~0;
667 urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
668 | URB_NO_SETUP_DMA_MAP);
669 return urb;
670}
671#endif /* 0 */
672
673/* XXX DISABLED, no users currently. If you wish to re-enable this
674 * XXX please determine whether the sync is to transfer ownership of
675 * XXX the buffer from device to cpu or vice verse, and thusly use the
676 * XXX appropriate _for_{cpu,device}() method. -DaveM
677 */
678#if 0
679
680/**
681 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
682 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
683 */
Oliver Neukum92516442007-01-23 15:55:28 -0500684void usb_buffer_dmasync(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685{
686 struct usb_bus *bus;
687 struct device *controller;
688
689 if (!urb
690 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
691 || !urb->dev
692 || !(bus = urb->dev->bus)
693 || !(controller = bus->controller))
694 return;
695
696 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500697 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500699 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500701 if (usb_pipecontrol(urb->pipe))
702 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500704 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 DMA_TO_DEVICE);
706 }
707}
708#endif
709
710/**
711 * usb_buffer_unmap - free DMA mapping(s) for an urb
712 * @urb: urb whose transfer_buffer will be unmapped
713 *
714 * Reverses the effect of usb_buffer_map().
715 */
716#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500717void usb_buffer_unmap(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718{
719 struct usb_bus *bus;
720 struct device *controller;
721
722 if (!urb
723 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
724 || !urb->dev
725 || !(bus = urb->dev->bus)
726 || !(controller = bus->controller))
727 return;
728
729 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500730 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500732 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500734 if (usb_pipecontrol(urb->pipe))
735 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500737 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 DMA_TO_DEVICE);
739 }
740 urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
741 | URB_NO_SETUP_DMA_MAP);
742}
743#endif /* 0 */
744
745/**
746 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
747 * @dev: device to which the scatterlist will be mapped
748 * @pipe: endpoint defining the mapping direction
749 * @sg: the scatterlist to map
750 * @nents: the number of entries in the scatterlist
751 *
752 * Return value is either < 0 (indicating no buffers could be mapped), or
753 * the number of DMA mapping array entries in the scatterlist.
754 *
755 * The caller is responsible for placing the resulting DMA addresses from
756 * the scatterlist into URB transfer buffer pointers, and for setting the
757 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
758 *
759 * Top I/O rates come from queuing URBs, instead of waiting for each one
760 * to complete before starting the next I/O. This is particularly easy
761 * to do with scatterlists. Just allocate and submit one URB for each DMA
762 * mapping entry returned, stopping on the first error or when all succeed.
763 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
764 *
765 * This call would normally be used when translating scatterlist requests,
766 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
767 * may be able to coalesce mappings for improved I/O efficiency.
768 *
769 * Reverse the effect of this call with usb_buffer_unmap_sg().
770 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300771int usb_buffer_map_sg(const struct usb_device *dev, unsigned pipe,
772 struct scatterlist *sg, int nents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773{
774 struct usb_bus *bus;
775 struct device *controller;
776
777 if (!dev
Oliver Neukum92516442007-01-23 15:55:28 -0500778 || usb_pipecontrol(pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 || !(bus = dev->bus)
780 || !(controller = bus->controller)
781 || !controller->dma_mask)
782 return -1;
783
784 // FIXME generic api broken like pci, can't report errors
Oliver Neukum92516442007-01-23 15:55:28 -0500785 return dma_map_sg(controller, sg, nents,
786 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787}
788
789/* XXX DISABLED, no users currently. If you wish to re-enable this
790 * XXX please determine whether the sync is to transfer ownership of
791 * XXX the buffer from device to cpu or vice verse, and thusly use the
792 * XXX appropriate _for_{cpu,device}() method. -DaveM
793 */
794#if 0
795
796/**
797 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
798 * @dev: device to which the scatterlist will be mapped
799 * @pipe: endpoint defining the mapping direction
800 * @sg: the scatterlist to synchronize
801 * @n_hw_ents: the positive return value from usb_buffer_map_sg
802 *
803 * Use this when you are re-using a scatterlist's data buffers for
804 * another USB request.
805 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300806void usb_buffer_dmasync_sg(const struct usb_device *dev, unsigned pipe,
807 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808{
809 struct usb_bus *bus;
810 struct device *controller;
811
812 if (!dev
813 || !(bus = dev->bus)
814 || !(controller = bus->controller)
815 || !controller->dma_mask)
816 return;
817
Oliver Neukum92516442007-01-23 15:55:28 -0500818 dma_sync_sg(controller, sg, n_hw_ents,
819 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820}
821#endif
822
823/**
824 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
825 * @dev: device to which the scatterlist will be mapped
826 * @pipe: endpoint defining the mapping direction
827 * @sg: the scatterlist to unmap
828 * @n_hw_ents: the positive return value from usb_buffer_map_sg
829 *
830 * Reverses the effect of usb_buffer_map_sg().
831 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300832void usb_buffer_unmap_sg(const struct usb_device *dev, unsigned pipe,
833 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834{
835 struct usb_bus *bus;
836 struct device *controller;
837
838 if (!dev
839 || !(bus = dev->bus)
840 || !(controller = bus->controller)
841 || !controller->dma_mask)
842 return;
843
Oliver Neukum92516442007-01-23 15:55:28 -0500844 dma_unmap_sg(controller, sg, n_hw_ents,
845 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846}
847
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848/* format to disable USB on kernel command line is: nousb */
Pete Zaitcevaafbf242005-12-20 14:15:04 -0800849__module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850
851/*
852 * for external read access to <nousb>
853 */
854int usb_disabled(void)
855{
856 return nousb;
857}
858
859/*
860 * Init
861 */
862static int __init usb_init(void)
863{
864 int retval;
865 if (nousb) {
Oliver Neukum92516442007-01-23 15:55:28 -0500866 pr_info("%s: USB support disabled\n", usbcore_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 return 0;
868 }
869
Alan Sternbd859282006-09-19 10:14:07 -0400870 retval = ksuspend_usb_init();
871 if (retval)
872 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 retval = bus_register(&usb_bus_type);
874 if (retval)
Alan Sternbd859282006-09-19 10:14:07 -0400875 goto bus_register_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 retval = usb_host_init();
877 if (retval)
878 goto host_init_failed;
879 retval = usb_major_init();
880 if (retval)
881 goto major_init_failed;
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200882 retval = usb_register(&usbfs_driver);
883 if (retval)
884 goto driver_register_failed;
885 retval = usbdev_init();
886 if (retval)
887 goto usbdevice_init_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 retval = usbfs_init();
889 if (retval)
890 goto fs_init_failed;
891 retval = usb_hub_init();
892 if (retval)
893 goto hub_init_failed;
Alan Stern8bb54ab2006-07-01 22:08:49 -0400894 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 if (!retval)
896 goto out;
897
898 usb_hub_cleanup();
899hub_init_failed:
900 usbfs_cleanup();
901fs_init_failed:
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200902 usbdev_cleanup();
903usbdevice_init_failed:
904 usb_deregister(&usbfs_driver);
905driver_register_failed:
906 usb_major_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907major_init_failed:
908 usb_host_cleanup();
909host_init_failed:
910 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400911bus_register_failed:
912 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913out:
914 return retval;
915}
916
917/*
918 * Cleanup
919 */
920static void __exit usb_exit(void)
921{
922 /* This will matter if shutdown/reboot does exitcalls. */
923 if (nousb)
924 return;
925
Alan Stern8bb54ab2006-07-01 22:08:49 -0400926 usb_deregister_device_driver(&usb_generic_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 usb_major_cleanup();
928 usbfs_cleanup();
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200929 usb_deregister(&usbfs_driver);
930 usbdev_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 usb_hub_cleanup();
932 usb_host_cleanup();
933 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400934 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935}
936
937subsys_initcall(usb_init);
938module_exit(usb_exit);
939
940/*
941 * USB may be built into the kernel or be built as modules.
942 * These symbols are exported for device (or host controller)
943 * driver modules to use.
944 */
945
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946EXPORT_SYMBOL(usb_disabled);
947
brian@murphy.dka3fdf4e2005-06-29 16:53:29 -0700948EXPORT_SYMBOL_GPL(usb_get_intf);
949EXPORT_SYMBOL_GPL(usb_put_intf);
950
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951EXPORT_SYMBOL(usb_put_dev);
952EXPORT_SYMBOL(usb_get_dev);
953EXPORT_SYMBOL(usb_hub_tt_clear_buffer);
954
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955EXPORT_SYMBOL(usb_lock_device_for_reset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956
Linus Torvalds1da177e2005-04-16 15:20:36 -0700957EXPORT_SYMBOL(usb_find_interface);
958EXPORT_SYMBOL(usb_ifnum_to_if);
959EXPORT_SYMBOL(usb_altnum_to_altsetting);
960
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961EXPORT_SYMBOL(__usb_get_extra_descriptor);
962
963EXPORT_SYMBOL(usb_find_device);
964EXPORT_SYMBOL(usb_get_current_frame_number);
965
Oliver Neukum92516442007-01-23 15:55:28 -0500966EXPORT_SYMBOL(usb_buffer_alloc);
967EXPORT_SYMBOL(usb_buffer_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968
969#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500970EXPORT_SYMBOL(usb_buffer_map);
971EXPORT_SYMBOL(usb_buffer_dmasync);
972EXPORT_SYMBOL(usb_buffer_unmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973#endif
974
Oliver Neukum92516442007-01-23 15:55:28 -0500975EXPORT_SYMBOL(usb_buffer_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500977EXPORT_SYMBOL(usb_buffer_dmasync_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978#endif
Oliver Neukum92516442007-01-23 15:55:28 -0500979EXPORT_SYMBOL(usb_buffer_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980
981MODULE_LICENSE("GPL");