blob: 18ddc5e67e39099bc9634e9e4def4232cfc4fdef [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Uwe Zeisbergerf30c2262006-10-03 23:01:26 +02002 * drivers/usb/core/usb.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * (C) Copyright Linus Torvalds 1999
5 * (C) Copyright Johannes Erdfelt 1999-2001
6 * (C) Copyright Andreas Gal 1999
7 * (C) Copyright Gregory P. Smith 1999
8 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9 * (C) Copyright Randy Dunlap 2000
10 * (C) Copyright David Brownell 2000-2004
11 * (C) Copyright Yggdrasil Computing, Inc. 2000
12 * (usb_device_id matching changes by Adam J. Richter)
13 * (C) Copyright Greg Kroah-Hartman 2002-2003
14 *
15 * NOTE! This is not actually a driver at all, rather this is
16 * just a collection of helper routines that implement the
17 * generic USB things that the real drivers can use..
18 *
19 * Think of this as a "USB library" rather than anything else.
20 * It should be considered a slave, with no callbacks. Callbacks
21 * are evil.
22 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/module.h>
Alan Sternb5e795f2007-02-20 15:00:53 -050025#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/string.h>
27#include <linux/bitops.h>
28#include <linux/slab.h>
29#include <linux/interrupt.h> /* for in_interrupt() */
30#include <linux/kmod.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <linux/errno.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/usb.h>
Arjan van de Ven4186ecf2006-01-11 15:55:29 +010035#include <linux/mutex.h>
Alan Sternbd859282006-09-19 10:14:07 -040036#include <linux/workqueue.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38#include <asm/io.h>
39#include <asm/scatterlist.h>
40#include <linux/mm.h>
41#include <linux/dma-mapping.h>
42
43#include "hcd.h"
44#include "usb.h"
45
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47const char *usbcore_name = "usbcore";
48
49static int nousb; /* Disable USB when built into kernel image */
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Alan Stern6b157c92007-03-13 16:37:30 -040051/* Workqueue for autosuspend and for remote wakeup of root hubs */
52struct workqueue_struct *ksuspend_usb_wq;
Alan Sternbd859282006-09-19 10:14:07 -040053
Alan Sternb5e795f2007-02-20 15:00:53 -050054#ifdef CONFIG_USB_SUSPEND
55static int usb_autosuspend_delay = 2; /* Default delay value,
56 * in seconds */
Alan Sterneaafbc32007-03-13 16:39:15 -040057module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
Alan Sternb5e795f2007-02-20 15:00:53 -050058MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
59
60#else
61#define usb_autosuspend_delay 0
62#endif
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Linus Torvalds1da177e2005-04-16 15:20:36 -070065/**
66 * usb_ifnum_to_if - get the interface object with a given interface number
67 * @dev: the device whose current configuration is considered
68 * @ifnum: the desired interface
69 *
70 * This walks the device descriptor for the currently active configuration
71 * and returns a pointer to the interface with that particular interface
72 * number, or null.
73 *
74 * Note that configuration descriptors are not required to assign interface
75 * numbers sequentially, so that it would be incorrect to assume that
76 * the first interface in that descriptor corresponds to interface zero.
77 * This routine helps device drivers avoid such mistakes.
78 * However, you should make sure that you do the right thing with any
79 * alternate settings available for this interfaces.
80 *
81 * Don't call this function unless you are bound to one of the interfaces
82 * on this device or you have locked the device!
83 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -030084struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
85 unsigned ifnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070086{
87 struct usb_host_config *config = dev->actconfig;
88 int i;
89
90 if (!config)
91 return NULL;
92 for (i = 0; i < config->desc.bNumInterfaces; i++)
93 if (config->interface[i]->altsetting[0]
94 .desc.bInterfaceNumber == ifnum)
95 return config->interface[i];
96
97 return NULL;
98}
99
100/**
101 * usb_altnum_to_altsetting - get the altsetting structure with a given
102 * alternate setting number.
103 * @intf: the interface containing the altsetting in question
104 * @altnum: the desired alternate setting number
105 *
106 * This searches the altsetting array of the specified interface for
107 * an entry with the correct bAlternateSetting value and returns a pointer
108 * to that entry, or null.
109 *
110 * Note that altsettings need not be stored sequentially by number, so
111 * it would be incorrect to assume that the first altsetting entry in
112 * the array corresponds to altsetting zero. This routine helps device
113 * drivers avoid such mistakes.
114 *
115 * Don't call this function unless you are bound to the intf interface
116 * or you have locked the device!
117 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300118struct usb_host_interface *usb_altnum_to_altsetting(const struct usb_interface *intf,
119 unsigned int altnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120{
121 int i;
122
123 for (i = 0; i < intf->num_altsetting; i++) {
124 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
125 return &intf->altsetting[i];
126 }
127 return NULL;
128}
129
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800130struct find_interface_arg {
131 int minor;
132 struct usb_interface *interface;
133};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800135static int __find_interface(struct device * dev, void * data)
136{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800137 struct find_interface_arg *arg = data;
138 struct usb_interface *intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800139
140 /* can't look at usb devices, only interfaces */
Alan Stern8bb54ab2006-07-01 22:08:49 -0400141 if (is_usb_device(dev))
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800142 return 0;
143
144 intf = to_usb_interface(dev);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800145 if (intf->minor != -1 && intf->minor == arg->minor) {
146 arg->interface = intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800147 return 1;
148 }
149 return 0;
150}
151
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152/**
153 * usb_find_interface - find usb_interface pointer for driver and device
154 * @drv: the driver whose current configuration is considered
155 * @minor: the minor number of the desired device
156 *
157 * This walks the driver device list and returns a pointer to the interface
158 * with the matching minor. Note, this only works for devices that share the
159 * USB major number.
160 */
161struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
162{
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800163 struct find_interface_arg argb;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700164 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800166 argb.minor = minor;
167 argb.interface = NULL;
Greg Kroah-Hartman1b21d5e2006-08-28 11:43:25 -0700168 /* eat the error, it will be in argb.interface */
169 retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb,
170 __find_interface);
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800171 return argb.interface;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172}
173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174/**
175 * usb_release_dev - free a usb device structure when all users of it are finished.
176 * @dev: device that's been disconnected
177 *
178 * Will be called only by the device core when all users of this usb device are
179 * done.
180 */
181static void usb_release_dev(struct device *dev)
182{
183 struct usb_device *udev;
184
185 udev = to_usb_device(dev);
186
Alan Sternbd859282006-09-19 10:14:07 -0400187#ifdef CONFIG_USB_SUSPEND
Alan Stern645daaa2006-08-30 15:47:02 -0400188 cancel_delayed_work(&udev->autosuspend);
Alan Sternbd859282006-09-19 10:14:07 -0400189 flush_workqueue(ksuspend_usb_wq);
Alan Stern645daaa2006-08-30 15:47:02 -0400190#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 usb_destroy_configuration(udev);
Alan Stern17200582006-08-30 11:32:52 -0400192 usb_put_hcd(bus_to_hcd(udev->bus));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 kfree(udev->product);
194 kfree(udev->manufacturer);
195 kfree(udev->serial);
196 kfree(udev);
197}
198
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100199struct device_type usb_device_type = {
200 .name = "usb_device",
201 .release = usb_release_dev,
202};
203
Alan Stern645daaa2006-08-30 15:47:02 -0400204#ifdef CONFIG_PM
205
Alan Sternbd859282006-09-19 10:14:07 -0400206static int ksuspend_usb_init(void)
207{
208 ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd");
209 if (!ksuspend_usb_wq)
210 return -ENOMEM;
211 return 0;
212}
213
214static void ksuspend_usb_cleanup(void)
215{
216 destroy_workqueue(ksuspend_usb_wq);
217}
218
Alan Sterndb063502006-11-13 15:02:04 -0500219#else
220
221#define ksuspend_usb_init() 0
222#define ksuspend_usb_cleanup() do {} while (0)
223
224#endif /* CONFIG_PM */
Alan Stern645daaa2006-08-30 15:47:02 -0400225
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226/**
227 * usb_alloc_dev - usb device constructor (usbcore-internal)
228 * @parent: hub to which device is connected; null to allocate a root hub
229 * @bus: bus used to access the device
230 * @port1: one-based index of port; ignored for root hubs
Oliver Neukum92516442007-01-23 15:55:28 -0500231 * Context: !in_interrupt()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 *
233 * Only hub drivers (including virtual root hub drivers for host
234 * controllers) should ever call this.
235 *
236 * This call may not be used in a non-sleeping context.
237 */
238struct usb_device *
239usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1)
240{
241 struct usb_device *dev;
242
Alan Stern0a1ef3b2005-10-24 15:38:24 -0400243 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 if (!dev)
245 return NULL;
246
Alan Stern17200582006-08-30 11:32:52 -0400247 if (!usb_get_hcd(bus_to_hcd(bus))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 kfree(dev);
249 return NULL;
250 }
251
252 device_initialize(&dev->dev);
253 dev->dev.bus = &usb_bus_type;
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100254 dev->dev.type = &usb_device_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255 dev->dev.dma_mask = bus->controller->dma_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 dev->state = USB_STATE_ATTACHED;
257
258 INIT_LIST_HEAD(&dev->ep0.urb_list);
259 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
260 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
261 /* ep0 maxpacket comes later, from device descriptor */
262 dev->ep_in[0] = dev->ep_out[0] = &dev->ep0;
263
264 /* Save readable and stable topology id, distinguishing devices
265 * by location for diagnostics, tools, driver model, etc. The
266 * string is a path along hub ports, from the root. Each device's
267 * dev->devpath will be stable until USB is re-cabled, and hubs
268 * are often labeled with these port numbers. The bus_id isn't
269 * as stable: bus->busnum changes easily from modprobe order,
270 * cardbus or pci hotplugging, and so on.
271 */
Oliver Neukum92516442007-01-23 15:55:28 -0500272 if (unlikely(!parent)) {
273 dev->devpath[0] = '0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274
275 dev->dev.parent = bus->controller;
Oliver Neukum92516442007-01-23 15:55:28 -0500276 sprintf(&dev->dev.bus_id[0], "usb%d", bus->busnum);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 } else {
278 /* match any labeling on the hubs; it's one-based */
Oliver Neukum92516442007-01-23 15:55:28 -0500279 if (parent->devpath[0] == '0')
280 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 "%d", port1);
282 else
Oliver Neukum92516442007-01-23 15:55:28 -0500283 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 "%s.%d", parent->devpath, port1);
285
286 dev->dev.parent = &parent->dev;
Oliver Neukum92516442007-01-23 15:55:28 -0500287 sprintf(&dev->dev.bus_id[0], "%d-%s",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 bus->busnum, dev->devpath);
289
290 /* hub driver sets up TT records */
291 }
292
Alan Stern12c3da32005-11-23 12:09:52 -0500293 dev->portnum = port1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 dev->bus = bus;
295 dev->parent = parent;
296 INIT_LIST_HEAD(&dev->filelist);
297
Alan Stern645daaa2006-08-30 15:47:02 -0400298#ifdef CONFIG_PM
299 mutex_init(&dev->pm_mutex);
David Howellsc4028952006-11-22 14:57:56 +0000300 INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
Alan Sternb5e795f2007-02-20 15:00:53 -0500301 dev->autosuspend_delay = usb_autosuspend_delay * HZ;
Alan Stern645daaa2006-08-30 15:47:02 -0400302#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 return dev;
304}
305
306/**
307 * usb_get_dev - increments the reference count of the usb device structure
308 * @dev: the device being referenced
309 *
310 * Each live reference to a device should be refcounted.
311 *
312 * Drivers for USB interfaces should normally record such references in
313 * their probe() methods, when they bind to an interface, and release
314 * them by calling usb_put_dev(), in their disconnect() methods.
315 *
316 * A pointer to the device with the incremented reference counter is returned.
317 */
318struct usb_device *usb_get_dev(struct usb_device *dev)
319{
320 if (dev)
321 get_device(&dev->dev);
322 return dev;
323}
324
325/**
326 * usb_put_dev - release a use of the usb device structure
327 * @dev: device that's been disconnected
328 *
329 * Must be called when a user of a device is finished with it. When the last
330 * user of the device calls this function, the memory of the device is freed.
331 */
332void usb_put_dev(struct usb_device *dev)
333{
334 if (dev)
335 put_device(&dev->dev);
336}
337
338/**
339 * usb_get_intf - increments the reference count of the usb interface structure
340 * @intf: the interface being referenced
341 *
342 * Each live reference to a interface must be refcounted.
343 *
344 * Drivers for USB interfaces should normally record such references in
345 * their probe() methods, when they bind to an interface, and release
346 * them by calling usb_put_intf(), in their disconnect() methods.
347 *
348 * A pointer to the interface with the incremented reference counter is
349 * returned.
350 */
351struct usb_interface *usb_get_intf(struct usb_interface *intf)
352{
353 if (intf)
354 get_device(&intf->dev);
355 return intf;
356}
357
358/**
359 * usb_put_intf - release a use of the usb interface structure
360 * @intf: interface that's been decremented
361 *
362 * Must be called when a user of an interface is finished with it. When the
363 * last user of the interface calls this function, the memory of the interface
364 * is freed.
365 */
366void usb_put_intf(struct usb_interface *intf)
367{
368 if (intf)
369 put_device(&intf->dev);
370}
371
372
373/* USB device locking
374 *
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500375 * USB devices and interfaces are locked using the semaphore in their
376 * embedded struct device. The hub driver guarantees that whenever a
377 * device is connected or disconnected, drivers are called with the
378 * USB device locked as well as their particular interface.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 *
380 * Complications arise when several devices are to be locked at the same
381 * time. Only hub-aware drivers that are part of usbcore ever have to
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500382 * do this; nobody else needs to worry about it. The rule for locking
383 * is simple:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 *
385 * When locking both a device and its parent, always lock the
386 * the parent first.
387 */
388
389/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390 * usb_lock_device_for_reset - cautiously acquire the lock for a
391 * usb device structure
392 * @udev: device that's being locked
393 * @iface: interface bound to the driver making the request (optional)
394 *
395 * Attempts to acquire the device lock, but fails if the device is
396 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
397 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
398 * lock, the routine polls repeatedly. This is to prevent deadlock with
399 * disconnect; in some drivers (such as usb-storage) the disconnect()
Alan Stern3ea15962005-08-11 10:15:39 -0400400 * or suspend() method will block waiting for a device reset to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 *
402 * Returns a negative error code for failure, otherwise 1 or 0 to indicate
403 * that the device will or will not have to be unlocked. (0 can be
404 * returned when an interface is given and is BINDING, because in that
405 * case the driver already owns the device lock.)
406 */
407int usb_lock_device_for_reset(struct usb_device *udev,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300408 const struct usb_interface *iface)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409{
Alan Stern3ea15962005-08-11 10:15:39 -0400410 unsigned long jiffies_expire = jiffies + HZ;
411
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 if (udev->state == USB_STATE_NOTATTACHED)
413 return -ENODEV;
414 if (udev->state == USB_STATE_SUSPENDED)
415 return -EHOSTUNREACH;
416 if (iface) {
417 switch (iface->condition) {
418 case USB_INTERFACE_BINDING:
419 return 0;
420 case USB_INTERFACE_BOUND:
421 break;
422 default:
423 return -EINTR;
424 }
425 }
426
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500427 while (usb_trylock_device(udev) != 0) {
Alan Stern3ea15962005-08-11 10:15:39 -0400428
429 /* If we can't acquire the lock after waiting one second,
430 * we're probably deadlocked */
431 if (time_after(jiffies, jiffies_expire))
432 return -EBUSY;
433
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 msleep(15);
435 if (udev->state == USB_STATE_NOTATTACHED)
436 return -ENODEV;
437 if (udev->state == USB_STATE_SUSPENDED)
438 return -EHOSTUNREACH;
439 if (iface && iface->condition != USB_INTERFACE_BOUND)
440 return -EINTR;
441 }
442 return 1;
443}
444
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
446static struct usb_device *match_device(struct usb_device *dev,
447 u16 vendor_id, u16 product_id)
448{
449 struct usb_device *ret_dev = NULL;
450 int child;
451
452 dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
453 le16_to_cpu(dev->descriptor.idVendor),
454 le16_to_cpu(dev->descriptor.idProduct));
455
456 /* see if this device matches */
457 if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
458 (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
Oliver Neukum92516442007-01-23 15:55:28 -0500459 dev_dbg(&dev->dev, "matched this device!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 ret_dev = usb_get_dev(dev);
461 goto exit;
462 }
463
464 /* look through all of the children of this device */
465 for (child = 0; child < dev->maxchild; ++child) {
466 if (dev->children[child]) {
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500467 usb_lock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 ret_dev = match_device(dev->children[child],
469 vendor_id, product_id);
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500470 usb_unlock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 if (ret_dev)
472 goto exit;
473 }
474 }
475exit:
476 return ret_dev;
477}
478
479/**
480 * usb_find_device - find a specific usb device in the system
481 * @vendor_id: the vendor id of the device to find
482 * @product_id: the product id of the device to find
483 *
484 * Returns a pointer to a struct usb_device if such a specified usb
485 * device is present in the system currently. The usage count of the
486 * device will be incremented if a device is found. Make sure to call
487 * usb_put_dev() when the caller is finished with the device.
488 *
489 * If a device with the specified vendor and product id is not found,
490 * NULL is returned.
491 */
492struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
493{
494 struct list_head *buslist;
495 struct usb_bus *bus;
496 struct usb_device *dev = NULL;
497
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100498 mutex_lock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 for (buslist = usb_bus_list.next;
500 buslist != &usb_bus_list;
501 buslist = buslist->next) {
502 bus = container_of(buslist, struct usb_bus, bus_list);
503 if (!bus->root_hub)
504 continue;
505 usb_lock_device(bus->root_hub);
506 dev = match_device(bus->root_hub, vendor_id, product_id);
507 usb_unlock_device(bus->root_hub);
508 if (dev)
509 goto exit;
510 }
511exit:
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100512 mutex_unlock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 return dev;
514}
515
516/**
517 * usb_get_current_frame_number - return current bus frame number
518 * @dev: the device whose bus is being queried
519 *
520 * Returns the current frame number for the USB host controller
521 * used with the given USB device. This can be used when scheduling
522 * isochronous requests.
523 *
524 * Note that different kinds of host controller have different
525 * "scheduling horizons". While one type might support scheduling only
526 * 32 frames into the future, others could support scheduling up to
527 * 1024 frames into the future.
528 */
529int usb_get_current_frame_number(struct usb_device *dev)
530{
Oliver Neukum92516442007-01-23 15:55:28 -0500531 return usb_hcd_get_frame_number(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532}
533
534/*-------------------------------------------------------------------*/
535/*
536 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
537 * extra field of the interface and endpoint descriptor structs.
538 */
539
540int __usb_get_extra_descriptor(char *buffer, unsigned size,
541 unsigned char type, void **ptr)
542{
543 struct usb_descriptor_header *header;
544
545 while (size >= sizeof(struct usb_descriptor_header)) {
546 header = (struct usb_descriptor_header *)buffer;
547
548 if (header->bLength < 2) {
549 printk(KERN_ERR
550 "%s: bogus descriptor, type %d length %d\n",
551 usbcore_name,
552 header->bDescriptorType,
553 header->bLength);
554 return -1;
555 }
556
557 if (header->bDescriptorType == type) {
558 *ptr = header;
559 return 0;
560 }
561
562 buffer += header->bLength;
563 size -= header->bLength;
564 }
565 return -1;
566}
567
568/**
569 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
570 * @dev: device the buffer will be used with
571 * @size: requested buffer size
572 * @mem_flags: affect whether allocation may block
573 * @dma: used to return DMA address of buffer
574 *
575 * Return value is either null (indicating no buffer could be allocated), or
576 * the cpu-space pointer to a buffer that may be used to perform DMA to the
577 * specified device. Such cpu-space buffers are returned along with the DMA
578 * address (through the pointer provided).
579 *
580 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
581 * to avoid behaviors like using "DMA bounce buffers", or tying down I/O
582 * mapping hardware for long idle periods. The implementation varies between
583 * platforms, depending on details of how DMA will work to this device.
584 * Using these buffers also helps prevent cacheline sharing problems on
585 * architectures where CPU caches are not DMA-coherent.
586 *
587 * When the buffer is no longer used, free it with usb_buffer_free().
588 */
Oliver Neukum92516442007-01-23 15:55:28 -0500589void *usb_buffer_alloc(
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 struct usb_device *dev,
591 size_t size,
Al Viro55016f12005-10-21 03:21:58 -0400592 gfp_t mem_flags,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 dma_addr_t *dma
594)
595{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400596 if (!dev || !dev->bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 return NULL;
Oliver Neukum92516442007-01-23 15:55:28 -0500598 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599}
600
601/**
602 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
603 * @dev: device the buffer was used with
604 * @size: requested buffer size
605 * @addr: CPU address of buffer
606 * @dma: DMA address of buffer
607 *
608 * This reclaims an I/O buffer, letting it be reused. The memory must have
609 * been allocated using usb_buffer_alloc(), and the parameters must match
610 * those provided in that allocation request.
611 */
Oliver Neukum92516442007-01-23 15:55:28 -0500612void usb_buffer_free(
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 struct usb_device *dev,
614 size_t size,
615 void *addr,
616 dma_addr_t dma
617)
618{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400619 if (!dev || !dev->bus)
Dmitry Torokhovb94badb2006-08-01 22:33:34 -0400620 return;
621 if (!addr)
622 return;
Oliver Neukum92516442007-01-23 15:55:28 -0500623 hcd_buffer_free(dev->bus, size, addr, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624}
625
626/**
627 * usb_buffer_map - create DMA mapping(s) for an urb
628 * @urb: urb whose transfer_buffer/setup_packet will be mapped
629 *
630 * Return value is either null (indicating no buffer could be mapped), or
631 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
632 * added to urb->transfer_flags if the operation succeeds. If the device
633 * is connected to this system through a non-DMA controller, this operation
634 * always succeeds.
635 *
636 * This call would normally be used for an urb which is reused, perhaps
637 * as the target of a large periodic transfer, with usb_buffer_dmasync()
638 * calls to synchronize memory and dma state.
639 *
640 * Reverse the effect of this call with usb_buffer_unmap().
641 */
642#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500643struct urb *usb_buffer_map(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644{
645 struct usb_bus *bus;
646 struct device *controller;
647
648 if (!urb
649 || !urb->dev
650 || !(bus = urb->dev->bus)
651 || !(controller = bus->controller))
652 return NULL;
653
654 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500655 urb->transfer_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 urb->transfer_buffer, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500657 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500659 if (usb_pipecontrol(urb->pipe))
660 urb->setup_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 urb->setup_packet,
Oliver Neukum92516442007-01-23 15:55:28 -0500662 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 DMA_TO_DEVICE);
664 // FIXME generic api broken like pci, can't report errors
665 // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0;
666 } else
667 urb->transfer_dma = ~0;
668 urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
669 | URB_NO_SETUP_DMA_MAP);
670 return urb;
671}
672#endif /* 0 */
673
674/* XXX DISABLED, no users currently. If you wish to re-enable this
675 * XXX please determine whether the sync is to transfer ownership of
676 * XXX the buffer from device to cpu or vice verse, and thusly use the
677 * XXX appropriate _for_{cpu,device}() method. -DaveM
678 */
679#if 0
680
681/**
682 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
683 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
684 */
Oliver Neukum92516442007-01-23 15:55:28 -0500685void usb_buffer_dmasync(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686{
687 struct usb_bus *bus;
688 struct device *controller;
689
690 if (!urb
691 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
692 || !urb->dev
693 || !(bus = urb->dev->bus)
694 || !(controller = bus->controller))
695 return;
696
697 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500698 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500700 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500702 if (usb_pipecontrol(urb->pipe))
703 dma_sync_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500705 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 DMA_TO_DEVICE);
707 }
708}
709#endif
710
711/**
712 * usb_buffer_unmap - free DMA mapping(s) for an urb
713 * @urb: urb whose transfer_buffer will be unmapped
714 *
715 * Reverses the effect of usb_buffer_map().
716 */
717#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500718void usb_buffer_unmap(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719{
720 struct usb_bus *bus;
721 struct device *controller;
722
723 if (!urb
724 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
725 || !urb->dev
726 || !(bus = urb->dev->bus)
727 || !(controller = bus->controller))
728 return;
729
730 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500731 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500733 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500735 if (usb_pipecontrol(urb->pipe))
736 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500738 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 DMA_TO_DEVICE);
740 }
741 urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
742 | URB_NO_SETUP_DMA_MAP);
743}
744#endif /* 0 */
745
746/**
747 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
748 * @dev: device to which the scatterlist will be mapped
749 * @pipe: endpoint defining the mapping direction
750 * @sg: the scatterlist to map
751 * @nents: the number of entries in the scatterlist
752 *
753 * Return value is either < 0 (indicating no buffers could be mapped), or
754 * the number of DMA mapping array entries in the scatterlist.
755 *
756 * The caller is responsible for placing the resulting DMA addresses from
757 * the scatterlist into URB transfer buffer pointers, and for setting the
758 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
759 *
760 * Top I/O rates come from queuing URBs, instead of waiting for each one
761 * to complete before starting the next I/O. This is particularly easy
762 * to do with scatterlists. Just allocate and submit one URB for each DMA
763 * mapping entry returned, stopping on the first error or when all succeed.
764 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
765 *
766 * This call would normally be used when translating scatterlist requests,
767 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
768 * may be able to coalesce mappings for improved I/O efficiency.
769 *
770 * Reverse the effect of this call with usb_buffer_unmap_sg().
771 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300772int usb_buffer_map_sg(const struct usb_device *dev, unsigned pipe,
773 struct scatterlist *sg, int nents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774{
775 struct usb_bus *bus;
776 struct device *controller;
777
778 if (!dev
Oliver Neukum92516442007-01-23 15:55:28 -0500779 || usb_pipecontrol(pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780 || !(bus = dev->bus)
781 || !(controller = bus->controller)
782 || !controller->dma_mask)
783 return -1;
784
785 // FIXME generic api broken like pci, can't report errors
Oliver Neukum92516442007-01-23 15:55:28 -0500786 return dma_map_sg(controller, sg, nents,
787 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788}
789
790/* XXX DISABLED, no users currently. If you wish to re-enable this
791 * XXX please determine whether the sync is to transfer ownership of
792 * XXX the buffer from device to cpu or vice verse, and thusly use the
793 * XXX appropriate _for_{cpu,device}() method. -DaveM
794 */
795#if 0
796
797/**
798 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
799 * @dev: device to which the scatterlist will be mapped
800 * @pipe: endpoint defining the mapping direction
801 * @sg: the scatterlist to synchronize
802 * @n_hw_ents: the positive return value from usb_buffer_map_sg
803 *
804 * Use this when you are re-using a scatterlist's data buffers for
805 * another USB request.
806 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300807void usb_buffer_dmasync_sg(const struct usb_device *dev, unsigned pipe,
808 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809{
810 struct usb_bus *bus;
811 struct device *controller;
812
813 if (!dev
814 || !(bus = dev->bus)
815 || !(controller = bus->controller)
816 || !controller->dma_mask)
817 return;
818
Oliver Neukum92516442007-01-23 15:55:28 -0500819 dma_sync_sg(controller, sg, n_hw_ents,
820 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821}
822#endif
823
824/**
825 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
826 * @dev: device to which the scatterlist will be mapped
827 * @pipe: endpoint defining the mapping direction
828 * @sg: the scatterlist to unmap
829 * @n_hw_ents: the positive return value from usb_buffer_map_sg
830 *
831 * Reverses the effect of usb_buffer_map_sg().
832 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300833void usb_buffer_unmap_sg(const struct usb_device *dev, unsigned pipe,
834 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835{
836 struct usb_bus *bus;
837 struct device *controller;
838
839 if (!dev
840 || !(bus = dev->bus)
841 || !(controller = bus->controller)
842 || !controller->dma_mask)
843 return;
844
Oliver Neukum92516442007-01-23 15:55:28 -0500845 dma_unmap_sg(controller, sg, n_hw_ents,
846 usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847}
848
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849/* format to disable USB on kernel command line is: nousb */
Pete Zaitcevaafbf242005-12-20 14:15:04 -0800850__module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851
852/*
853 * for external read access to <nousb>
854 */
855int usb_disabled(void)
856{
857 return nousb;
858}
859
860/*
861 * Init
862 */
863static int __init usb_init(void)
864{
865 int retval;
866 if (nousb) {
Oliver Neukum92516442007-01-23 15:55:28 -0500867 pr_info("%s: USB support disabled\n", usbcore_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 return 0;
869 }
870
Alan Sternbd859282006-09-19 10:14:07 -0400871 retval = ksuspend_usb_init();
872 if (retval)
873 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 retval = bus_register(&usb_bus_type);
875 if (retval)
Alan Sternbd859282006-09-19 10:14:07 -0400876 goto bus_register_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 retval = usb_host_init();
878 if (retval)
879 goto host_init_failed;
880 retval = usb_major_init();
881 if (retval)
882 goto major_init_failed;
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200883 retval = usb_register(&usbfs_driver);
884 if (retval)
885 goto driver_register_failed;
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100886 retval = usb_devio_init();
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200887 if (retval)
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100888 goto usb_devio_init_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 retval = usbfs_init();
890 if (retval)
891 goto fs_init_failed;
892 retval = usb_hub_init();
893 if (retval)
894 goto hub_init_failed;
Alan Stern8bb54ab2006-07-01 22:08:49 -0400895 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700896 if (!retval)
897 goto out;
898
899 usb_hub_cleanup();
900hub_init_failed:
901 usbfs_cleanup();
902fs_init_failed:
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100903 usb_devio_cleanup();
904usb_devio_init_failed:
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200905 usb_deregister(&usbfs_driver);
906driver_register_failed:
907 usb_major_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908major_init_failed:
909 usb_host_cleanup();
910host_init_failed:
911 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400912bus_register_failed:
913 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914out:
915 return retval;
916}
917
918/*
919 * Cleanup
920 */
921static void __exit usb_exit(void)
922{
923 /* This will matter if shutdown/reboot does exitcalls. */
924 if (nousb)
925 return;
926
Alan Stern8bb54ab2006-07-01 22:08:49 -0400927 usb_deregister_device_driver(&usb_generic_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 usb_major_cleanup();
929 usbfs_cleanup();
Kay Sieversfbf82fd2005-07-31 01:05:53 +0200930 usb_deregister(&usbfs_driver);
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100931 usb_devio_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 usb_hub_cleanup();
933 usb_host_cleanup();
934 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -0400935 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936}
937
938subsys_initcall(usb_init);
939module_exit(usb_exit);
940
941/*
942 * USB may be built into the kernel or be built as modules.
943 * These symbols are exported for device (or host controller)
944 * driver modules to use.
945 */
946
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947EXPORT_SYMBOL(usb_disabled);
948
brian@murphy.dka3fdf4e2005-06-29 16:53:29 -0700949EXPORT_SYMBOL_GPL(usb_get_intf);
950EXPORT_SYMBOL_GPL(usb_put_intf);
951
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952EXPORT_SYMBOL(usb_put_dev);
953EXPORT_SYMBOL(usb_get_dev);
954EXPORT_SYMBOL(usb_hub_tt_clear_buffer);
955
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956EXPORT_SYMBOL(usb_lock_device_for_reset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700957
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958EXPORT_SYMBOL(usb_find_interface);
959EXPORT_SYMBOL(usb_ifnum_to_if);
960EXPORT_SYMBOL(usb_altnum_to_altsetting);
961
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962EXPORT_SYMBOL(__usb_get_extra_descriptor);
963
964EXPORT_SYMBOL(usb_find_device);
965EXPORT_SYMBOL(usb_get_current_frame_number);
966
Oliver Neukum92516442007-01-23 15:55:28 -0500967EXPORT_SYMBOL(usb_buffer_alloc);
968EXPORT_SYMBOL(usb_buffer_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969
970#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500971EXPORT_SYMBOL(usb_buffer_map);
972EXPORT_SYMBOL(usb_buffer_dmasync);
973EXPORT_SYMBOL(usb_buffer_unmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974#endif
975
Oliver Neukum92516442007-01-23 15:55:28 -0500976EXPORT_SYMBOL(usb_buffer_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500978EXPORT_SYMBOL(usb_buffer_dmasync_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979#endif
Oliver Neukum92516442007-01-23 15:55:28 -0500980EXPORT_SYMBOL(usb_buffer_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981
982MODULE_LICENSE("GPL");