Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f30c2269 | 2 | * drivers/usb/core/usb.c |
1da177e4 LT |
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 | ||
1da177e4 | 24 | #include <linux/module.h> |
b5e795f8 | 25 | #include <linux/moduleparam.h> |
1da177e4 LT |
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> | |
1da177e4 | 34 | #include <linux/usb.h> |
4186ecf8 | 35 | #include <linux/mutex.h> |
bd859281 | 36 | #include <linux/workqueue.h> |
1da177e4 LT |
37 | |
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 | ||
1da177e4 LT |
46 | |
47 | const char *usbcore_name = "usbcore"; | |
48 | ||
49 | static int nousb; /* Disable USB when built into kernel image */ | |
1da177e4 | 50 | |
6b157c9b AS |
51 | /* Workqueue for autosuspend and for remote wakeup of root hubs */ |
52 | struct workqueue_struct *ksuspend_usb_wq; | |
bd859281 | 53 | |
b5e795f8 AS |
54 | #ifdef CONFIG_USB_SUSPEND |
55 | static int usb_autosuspend_delay = 2; /* Default delay value, | |
56 | * in seconds */ | |
eaafbc3a | 57 | module_param_named(autosuspend, usb_autosuspend_delay, int, 0644); |
b5e795f8 AS |
58 | MODULE_PARM_DESC(autosuspend, "default autosuspend delay"); |
59 | ||
60 | #else | |
61 | #define usb_autosuspend_delay 0 | |
62 | #endif | |
63 | ||
1da177e4 | 64 | |
1da177e4 LT |
65 | /** |
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 | */ | |
095bc335 LFC |
84 | struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev, |
85 | unsigned ifnum) | |
1da177e4 LT |
86 | { |
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 | */ | |
095bc335 LFC |
118 | struct usb_host_interface *usb_altnum_to_altsetting(const struct usb_interface *intf, |
119 | unsigned int altnum) | |
1da177e4 LT |
120 | { |
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 | ||
f5691d70 PZ |
130 | struct find_interface_arg { |
131 | int minor; | |
132 | struct usb_interface *interface; | |
133 | }; | |
1da177e4 | 134 | |
6034a080 | 135 | static int __find_interface(struct device * dev, void * data) |
136 | { | |
f5691d70 PZ |
137 | struct find_interface_arg *arg = data; |
138 | struct usb_interface *intf; | |
6034a080 | 139 | |
140 | /* can't look at usb devices, only interfaces */ | |
8bb54ab5 | 141 | if (is_usb_device(dev)) |
6034a080 | 142 | return 0; |
143 | ||
144 | intf = to_usb_interface(dev); | |
f5691d70 PZ |
145 | if (intf->minor != -1 && intf->minor == arg->minor) { |
146 | arg->interface = intf; | |
6034a080 | 147 | return 1; |
148 | } | |
149 | return 0; | |
150 | } | |
151 | ||
1da177e4 LT |
152 | /** |
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 | */ | |
161 | struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) | |
162 | { | |
f5691d70 | 163 | struct find_interface_arg argb; |
1b21d5e1 | 164 | int retval; |
1da177e4 | 165 | |
f5691d70 PZ |
166 | argb.minor = minor; |
167 | argb.interface = NULL; | |
1b21d5e1 GKH |
168 | /* eat the error, it will be in argb.interface */ |
169 | retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb, | |
170 | __find_interface); | |
f5691d70 | 171 | return argb.interface; |
1da177e4 LT |
172 | } |
173 | ||
1da177e4 LT |
174 | /** |
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 | */ | |
181 | static void usb_release_dev(struct device *dev) | |
182 | { | |
183 | struct usb_device *udev; | |
184 | ||
185 | udev = to_usb_device(dev); | |
186 | ||
187 | usb_destroy_configuration(udev); | |
17200583 | 188 | usb_put_hcd(bus_to_hcd(udev->bus)); |
1da177e4 LT |
189 | kfree(udev->product); |
190 | kfree(udev->manufacturer); | |
191 | kfree(udev->serial); | |
192 | kfree(udev); | |
193 | } | |
194 | ||
9f8b17e6 KS |
195 | struct device_type usb_device_type = { |
196 | .name = "usb_device", | |
197 | .release = usb_release_dev, | |
198 | }; | |
199 | ||
645daaab AS |
200 | #ifdef CONFIG_PM |
201 | ||
bd859281 AS |
202 | static int ksuspend_usb_init(void) |
203 | { | |
7ed92f1a AS |
204 | /* This workqueue is supposed to be both freezable and |
205 | * singlethreaded. Its job doesn't justify running on more | |
206 | * than one CPU. | |
207 | */ | |
208 | ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd"); | |
bd859281 AS |
209 | if (!ksuspend_usb_wq) |
210 | return -ENOMEM; | |
211 | return 0; | |
212 | } | |
213 | ||
214 | static void ksuspend_usb_cleanup(void) | |
215 | { | |
216 | destroy_workqueue(ksuspend_usb_wq); | |
217 | } | |
218 | ||
db063507 AS |
219 | #else |
220 | ||
221 | #define ksuspend_usb_init() 0 | |
222 | #define ksuspend_usb_cleanup() do {} while (0) | |
223 | ||
224 | #endif /* CONFIG_PM */ | |
645daaab | 225 | |
1da177e4 LT |
226 | /** |
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 | |
9251644a | 231 | * Context: !in_interrupt() |
1da177e4 LT |
232 | * |
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 | */ | |
238 | struct usb_device * | |
239 | usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) | |
240 | { | |
241 | struct usb_device *dev; | |
242 | ||
0a1ef3b5 | 243 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
1da177e4 LT |
244 | if (!dev) |
245 | return NULL; | |
246 | ||
17200583 | 247 | if (!usb_get_hcd(bus_to_hcd(bus))) { |
1da177e4 LT |
248 | kfree(dev); |
249 | return NULL; | |
250 | } | |
251 | ||
252 | device_initialize(&dev->dev); | |
253 | dev->dev.bus = &usb_bus_type; | |
9f8b17e6 | 254 | dev->dev.type = &usb_device_type; |
1da177e4 | 255 | dev->dev.dma_mask = bus->controller->dma_mask; |
70f458f6 | 256 | set_dev_node(&dev->dev, dev_to_node(bus->controller)); |
1da177e4 LT |
257 | dev->state = USB_STATE_ATTACHED; |
258 | ||
259 | INIT_LIST_HEAD(&dev->ep0.urb_list); | |
260 | dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE; | |
261 | dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT; | |
262 | /* ep0 maxpacket comes later, from device descriptor */ | |
bdd016ba | 263 | usb_enable_endpoint(dev, &dev->ep0); |
1da177e4 LT |
264 | |
265 | /* Save readable and stable topology id, distinguishing devices | |
266 | * by location for diagnostics, tools, driver model, etc. The | |
267 | * string is a path along hub ports, from the root. Each device's | |
268 | * dev->devpath will be stable until USB is re-cabled, and hubs | |
269 | * are often labeled with these port numbers. The bus_id isn't | |
270 | * as stable: bus->busnum changes easily from modprobe order, | |
271 | * cardbus or pci hotplugging, and so on. | |
272 | */ | |
9251644a ON |
273 | if (unlikely(!parent)) { |
274 | dev->devpath[0] = '0'; | |
1da177e4 LT |
275 | |
276 | dev->dev.parent = bus->controller; | |
9251644a | 277 | sprintf(&dev->dev.bus_id[0], "usb%d", bus->busnum); |
1da177e4 LT |
278 | } else { |
279 | /* match any labeling on the hubs; it's one-based */ | |
9251644a ON |
280 | if (parent->devpath[0] == '0') |
281 | snprintf(dev->devpath, sizeof dev->devpath, | |
1da177e4 LT |
282 | "%d", port1); |
283 | else | |
9251644a | 284 | snprintf(dev->devpath, sizeof dev->devpath, |
1da177e4 LT |
285 | "%s.%d", parent->devpath, port1); |
286 | ||
287 | dev->dev.parent = &parent->dev; | |
9251644a | 288 | sprintf(&dev->dev.bus_id[0], "%d-%s", |
1da177e4 LT |
289 | bus->busnum, dev->devpath); |
290 | ||
291 | /* hub driver sets up TT records */ | |
292 | } | |
293 | ||
12c3da34 | 294 | dev->portnum = port1; |
1da177e4 LT |
295 | dev->bus = bus; |
296 | dev->parent = parent; | |
297 | INIT_LIST_HEAD(&dev->filelist); | |
298 | ||
645daaab AS |
299 | #ifdef CONFIG_PM |
300 | mutex_init(&dev->pm_mutex); | |
c4028958 | 301 | INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work); |
b5e795f8 | 302 | dev->autosuspend_delay = usb_autosuspend_delay * HZ; |
645daaab | 303 | #endif |
1da177e4 LT |
304 | return dev; |
305 | } | |
306 | ||
307 | /** | |
308 | * usb_get_dev - increments the reference count of the usb device structure | |
309 | * @dev: the device being referenced | |
310 | * | |
311 | * Each live reference to a device should be refcounted. | |
312 | * | |
313 | * Drivers for USB interfaces should normally record such references in | |
314 | * their probe() methods, when they bind to an interface, and release | |
315 | * them by calling usb_put_dev(), in their disconnect() methods. | |
316 | * | |
317 | * A pointer to the device with the incremented reference counter is returned. | |
318 | */ | |
319 | struct usb_device *usb_get_dev(struct usb_device *dev) | |
320 | { | |
321 | if (dev) | |
322 | get_device(&dev->dev); | |
323 | return dev; | |
324 | } | |
325 | ||
326 | /** | |
327 | * usb_put_dev - release a use of the usb device structure | |
328 | * @dev: device that's been disconnected | |
329 | * | |
330 | * Must be called when a user of a device is finished with it. When the last | |
331 | * user of the device calls this function, the memory of the device is freed. | |
332 | */ | |
333 | void usb_put_dev(struct usb_device *dev) | |
334 | { | |
335 | if (dev) | |
336 | put_device(&dev->dev); | |
337 | } | |
338 | ||
339 | /** | |
340 | * usb_get_intf - increments the reference count of the usb interface structure | |
341 | * @intf: the interface being referenced | |
342 | * | |
343 | * Each live reference to a interface must be refcounted. | |
344 | * | |
345 | * Drivers for USB interfaces should normally record such references in | |
346 | * their probe() methods, when they bind to an interface, and release | |
347 | * them by calling usb_put_intf(), in their disconnect() methods. | |
348 | * | |
349 | * A pointer to the interface with the incremented reference counter is | |
350 | * returned. | |
351 | */ | |
352 | struct usb_interface *usb_get_intf(struct usb_interface *intf) | |
353 | { | |
354 | if (intf) | |
355 | get_device(&intf->dev); | |
356 | return intf; | |
357 | } | |
358 | ||
359 | /** | |
360 | * usb_put_intf - release a use of the usb interface structure | |
361 | * @intf: interface that's been decremented | |
362 | * | |
363 | * Must be called when a user of an interface is finished with it. When the | |
364 | * last user of the interface calls this function, the memory of the interface | |
365 | * is freed. | |
366 | */ | |
367 | void usb_put_intf(struct usb_interface *intf) | |
368 | { | |
369 | if (intf) | |
370 | put_device(&intf->dev); | |
371 | } | |
372 | ||
373 | ||
374 | /* USB device locking | |
375 | * | |
9ad3d6cc AS |
376 | * USB devices and interfaces are locked using the semaphore in their |
377 | * embedded struct device. The hub driver guarantees that whenever a | |
378 | * device is connected or disconnected, drivers are called with the | |
379 | * USB device locked as well as their particular interface. | |
1da177e4 LT |
380 | * |
381 | * Complications arise when several devices are to be locked at the same | |
382 | * time. Only hub-aware drivers that are part of usbcore ever have to | |
9ad3d6cc AS |
383 | * do this; nobody else needs to worry about it. The rule for locking |
384 | * is simple: | |
1da177e4 LT |
385 | * |
386 | * When locking both a device and its parent, always lock the | |
387 | * the parent first. | |
388 | */ | |
389 | ||
1da177e4 LT |
390 | /** |
391 | * usb_lock_device_for_reset - cautiously acquire the lock for a | |
392 | * usb device structure | |
393 | * @udev: device that's being locked | |
394 | * @iface: interface bound to the driver making the request (optional) | |
395 | * | |
396 | * Attempts to acquire the device lock, but fails if the device is | |
397 | * NOTATTACHED or SUSPENDED, or if iface is specified and the interface | |
398 | * is neither BINDING nor BOUND. Rather than sleeping to wait for the | |
399 | * lock, the routine polls repeatedly. This is to prevent deadlock with | |
400 | * disconnect; in some drivers (such as usb-storage) the disconnect() | |
3ea15966 | 401 | * or suspend() method will block waiting for a device reset to complete. |
1da177e4 LT |
402 | * |
403 | * Returns a negative error code for failure, otherwise 1 or 0 to indicate | |
404 | * that the device will or will not have to be unlocked. (0 can be | |
405 | * returned when an interface is given and is BINDING, because in that | |
406 | * case the driver already owns the device lock.) | |
407 | */ | |
408 | int usb_lock_device_for_reset(struct usb_device *udev, | |
095bc335 | 409 | const struct usb_interface *iface) |
1da177e4 | 410 | { |
3ea15966 AS |
411 | unsigned long jiffies_expire = jiffies + HZ; |
412 | ||
1da177e4 LT |
413 | if (udev->state == USB_STATE_NOTATTACHED) |
414 | return -ENODEV; | |
415 | if (udev->state == USB_STATE_SUSPENDED) | |
416 | return -EHOSTUNREACH; | |
417 | if (iface) { | |
418 | switch (iface->condition) { | |
419 | case USB_INTERFACE_BINDING: | |
420 | return 0; | |
421 | case USB_INTERFACE_BOUND: | |
422 | break; | |
423 | default: | |
424 | return -EINTR; | |
425 | } | |
426 | } | |
427 | ||
9ad3d6cc | 428 | while (usb_trylock_device(udev) != 0) { |
3ea15966 AS |
429 | |
430 | /* If we can't acquire the lock after waiting one second, | |
431 | * we're probably deadlocked */ | |
432 | if (time_after(jiffies, jiffies_expire)) | |
433 | return -EBUSY; | |
434 | ||
1da177e4 LT |
435 | msleep(15); |
436 | if (udev->state == USB_STATE_NOTATTACHED) | |
437 | return -ENODEV; | |
438 | if (udev->state == USB_STATE_SUSPENDED) | |
439 | return -EHOSTUNREACH; | |
440 | if (iface && iface->condition != USB_INTERFACE_BOUND) | |
441 | return -EINTR; | |
442 | } | |
443 | return 1; | |
444 | } | |
445 | ||
1da177e4 LT |
446 | |
447 | static struct usb_device *match_device(struct usb_device *dev, | |
448 | u16 vendor_id, u16 product_id) | |
449 | { | |
450 | struct usb_device *ret_dev = NULL; | |
451 | int child; | |
452 | ||
453 | dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n", | |
454 | le16_to_cpu(dev->descriptor.idVendor), | |
455 | le16_to_cpu(dev->descriptor.idProduct)); | |
456 | ||
457 | /* see if this device matches */ | |
458 | if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) && | |
459 | (product_id == le16_to_cpu(dev->descriptor.idProduct))) { | |
9251644a | 460 | dev_dbg(&dev->dev, "matched this device!\n"); |
1da177e4 LT |
461 | ret_dev = usb_get_dev(dev); |
462 | goto exit; | |
463 | } | |
464 | ||
465 | /* look through all of the children of this device */ | |
466 | for (child = 0; child < dev->maxchild; ++child) { | |
467 | if (dev->children[child]) { | |
9ad3d6cc | 468 | usb_lock_device(dev->children[child]); |
1da177e4 LT |
469 | ret_dev = match_device(dev->children[child], |
470 | vendor_id, product_id); | |
9ad3d6cc | 471 | usb_unlock_device(dev->children[child]); |
1da177e4 LT |
472 | if (ret_dev) |
473 | goto exit; | |
474 | } | |
475 | } | |
476 | exit: | |
477 | return ret_dev; | |
478 | } | |
479 | ||
480 | /** | |
481 | * usb_find_device - find a specific usb device in the system | |
482 | * @vendor_id: the vendor id of the device to find | |
483 | * @product_id: the product id of the device to find | |
484 | * | |
485 | * Returns a pointer to a struct usb_device if such a specified usb | |
486 | * device is present in the system currently. The usage count of the | |
487 | * device will be incremented if a device is found. Make sure to call | |
488 | * usb_put_dev() when the caller is finished with the device. | |
489 | * | |
490 | * If a device with the specified vendor and product id is not found, | |
491 | * NULL is returned. | |
492 | */ | |
493 | struct usb_device *usb_find_device(u16 vendor_id, u16 product_id) | |
494 | { | |
495 | struct list_head *buslist; | |
496 | struct usb_bus *bus; | |
497 | struct usb_device *dev = NULL; | |
498 | ||
4186ecf8 | 499 | mutex_lock(&usb_bus_list_lock); |
1da177e4 LT |
500 | for (buslist = usb_bus_list.next; |
501 | buslist != &usb_bus_list; | |
502 | buslist = buslist->next) { | |
503 | bus = container_of(buslist, struct usb_bus, bus_list); | |
504 | if (!bus->root_hub) | |
505 | continue; | |
506 | usb_lock_device(bus->root_hub); | |
507 | dev = match_device(bus->root_hub, vendor_id, product_id); | |
508 | usb_unlock_device(bus->root_hub); | |
509 | if (dev) | |
510 | goto exit; | |
511 | } | |
512 | exit: | |
4186ecf8 | 513 | mutex_unlock(&usb_bus_list_lock); |
1da177e4 LT |
514 | return dev; |
515 | } | |
516 | ||
517 | /** | |
518 | * usb_get_current_frame_number - return current bus frame number | |
519 | * @dev: the device whose bus is being queried | |
520 | * | |
521 | * Returns the current frame number for the USB host controller | |
522 | * used with the given USB device. This can be used when scheduling | |
523 | * isochronous requests. | |
524 | * | |
525 | * Note that different kinds of host controller have different | |
526 | * "scheduling horizons". While one type might support scheduling only | |
527 | * 32 frames into the future, others could support scheduling up to | |
528 | * 1024 frames into the future. | |
529 | */ | |
530 | int usb_get_current_frame_number(struct usb_device *dev) | |
531 | { | |
9251644a | 532 | return usb_hcd_get_frame_number(dev); |
1da177e4 LT |
533 | } |
534 | ||
535 | /*-------------------------------------------------------------------*/ | |
536 | /* | |
537 | * __usb_get_extra_descriptor() finds a descriptor of specific type in the | |
538 | * extra field of the interface and endpoint descriptor structs. | |
539 | */ | |
540 | ||
541 | int __usb_get_extra_descriptor(char *buffer, unsigned size, | |
542 | unsigned char type, void **ptr) | |
543 | { | |
544 | struct usb_descriptor_header *header; | |
545 | ||
546 | while (size >= sizeof(struct usb_descriptor_header)) { | |
547 | header = (struct usb_descriptor_header *)buffer; | |
548 | ||
549 | if (header->bLength < 2) { | |
550 | printk(KERN_ERR | |
551 | "%s: bogus descriptor, type %d length %d\n", | |
552 | usbcore_name, | |
553 | header->bDescriptorType, | |
554 | header->bLength); | |
555 | return -1; | |
556 | } | |
557 | ||
558 | if (header->bDescriptorType == type) { | |
559 | *ptr = header; | |
560 | return 0; | |
561 | } | |
562 | ||
563 | buffer += header->bLength; | |
564 | size -= header->bLength; | |
565 | } | |
566 | return -1; | |
567 | } | |
568 | ||
569 | /** | |
570 | * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP | |
571 | * @dev: device the buffer will be used with | |
572 | * @size: requested buffer size | |
573 | * @mem_flags: affect whether allocation may block | |
574 | * @dma: used to return DMA address of buffer | |
575 | * | |
576 | * Return value is either null (indicating no buffer could be allocated), or | |
577 | * the cpu-space pointer to a buffer that may be used to perform DMA to the | |
578 | * specified device. Such cpu-space buffers are returned along with the DMA | |
579 | * address (through the pointer provided). | |
580 | * | |
581 | * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags | |
fbf54dd3 DB |
582 | * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU |
583 | * hardware during URB completion/resubmit. The implementation varies between | |
1da177e4 | 584 | * platforms, depending on details of how DMA will work to this device. |
fbf54dd3 DB |
585 | * Using these buffers also eliminates cacheline sharing problems on |
586 | * architectures where CPU caches are not DMA-coherent. On systems without | |
587 | * bus-snooping caches, these buffers are uncached. | |
1da177e4 LT |
588 | * |
589 | * When the buffer is no longer used, free it with usb_buffer_free(). | |
590 | */ | |
9251644a | 591 | void *usb_buffer_alloc( |
1da177e4 LT |
592 | struct usb_device *dev, |
593 | size_t size, | |
55016f10 | 594 | gfp_t mem_flags, |
1da177e4 LT |
595 | dma_addr_t *dma |
596 | ) | |
597 | { | |
a6d2bb9f | 598 | if (!dev || !dev->bus) |
1da177e4 | 599 | return NULL; |
9251644a | 600 | return hcd_buffer_alloc(dev->bus, size, mem_flags, dma); |
1da177e4 LT |
601 | } |
602 | ||
603 | /** | |
604 | * usb_buffer_free - free memory allocated with usb_buffer_alloc() | |
605 | * @dev: device the buffer was used with | |
606 | * @size: requested buffer size | |
607 | * @addr: CPU address of buffer | |
608 | * @dma: DMA address of buffer | |
609 | * | |
610 | * This reclaims an I/O buffer, letting it be reused. The memory must have | |
611 | * been allocated using usb_buffer_alloc(), and the parameters must match | |
fbf54dd3 | 612 | * those provided in that allocation request. |
1da177e4 | 613 | */ |
9251644a | 614 | void usb_buffer_free( |
1da177e4 LT |
615 | struct usb_device *dev, |
616 | size_t size, | |
617 | void *addr, | |
618 | dma_addr_t dma | |
619 | ) | |
620 | { | |
a6d2bb9f | 621 | if (!dev || !dev->bus) |
b94badbb DT |
622 | return; |
623 | if (!addr) | |
624 | return; | |
9251644a | 625 | hcd_buffer_free(dev->bus, size, addr, dma); |
1da177e4 LT |
626 | } |
627 | ||
628 | /** | |
629 | * usb_buffer_map - create DMA mapping(s) for an urb | |
630 | * @urb: urb whose transfer_buffer/setup_packet will be mapped | |
631 | * | |
632 | * Return value is either null (indicating no buffer could be mapped), or | |
633 | * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are | |
634 | * added to urb->transfer_flags if the operation succeeds. If the device | |
635 | * is connected to this system through a non-DMA controller, this operation | |
636 | * always succeeds. | |
637 | * | |
638 | * This call would normally be used for an urb which is reused, perhaps | |
639 | * as the target of a large periodic transfer, with usb_buffer_dmasync() | |
640 | * calls to synchronize memory and dma state. | |
641 | * | |
642 | * Reverse the effect of this call with usb_buffer_unmap(). | |
643 | */ | |
644 | #if 0 | |
9251644a | 645 | struct urb *usb_buffer_map(struct urb *urb) |
1da177e4 LT |
646 | { |
647 | struct usb_bus *bus; | |
648 | struct device *controller; | |
649 | ||
650 | if (!urb | |
651 | || !urb->dev | |
652 | || !(bus = urb->dev->bus) | |
653 | || !(controller = bus->controller)) | |
654 | return NULL; | |
655 | ||
656 | if (controller->dma_mask) { | |
9251644a | 657 | urb->transfer_dma = dma_map_single(controller, |
1da177e4 | 658 | urb->transfer_buffer, urb->transfer_buffer_length, |
9251644a | 659 | usb_pipein(urb->pipe) |
1da177e4 | 660 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
661 | if (usb_pipecontrol(urb->pipe)) |
662 | urb->setup_dma = dma_map_single(controller, | |
1da177e4 | 663 | urb->setup_packet, |
9251644a | 664 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
665 | DMA_TO_DEVICE); |
666 | // FIXME generic api broken like pci, can't report errors | |
667 | // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; | |
668 | } else | |
669 | urb->transfer_dma = ~0; | |
670 | urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | |
671 | | URB_NO_SETUP_DMA_MAP); | |
672 | return urb; | |
673 | } | |
674 | #endif /* 0 */ | |
675 | ||
676 | /* XXX DISABLED, no users currently. If you wish to re-enable this | |
677 | * XXX please determine whether the sync is to transfer ownership of | |
678 | * XXX the buffer from device to cpu or vice verse, and thusly use the | |
679 | * XXX appropriate _for_{cpu,device}() method. -DaveM | |
680 | */ | |
681 | #if 0 | |
682 | ||
683 | /** | |
684 | * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s) | |
685 | * @urb: urb whose transfer_buffer/setup_packet will be synchronized | |
686 | */ | |
9251644a | 687 | void usb_buffer_dmasync(struct urb *urb) |
1da177e4 LT |
688 | { |
689 | struct usb_bus *bus; | |
690 | struct device *controller; | |
691 | ||
692 | if (!urb | |
693 | || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) | |
694 | || !urb->dev | |
695 | || !(bus = urb->dev->bus) | |
696 | || !(controller = bus->controller)) | |
697 | return; | |
698 | ||
699 | if (controller->dma_mask) { | |
9251644a | 700 | dma_sync_single(controller, |
1da177e4 | 701 | urb->transfer_dma, urb->transfer_buffer_length, |
9251644a | 702 | usb_pipein(urb->pipe) |
1da177e4 | 703 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
704 | if (usb_pipecontrol(urb->pipe)) |
705 | dma_sync_single(controller, | |
1da177e4 | 706 | urb->setup_dma, |
9251644a | 707 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
708 | DMA_TO_DEVICE); |
709 | } | |
710 | } | |
711 | #endif | |
712 | ||
713 | /** | |
714 | * usb_buffer_unmap - free DMA mapping(s) for an urb | |
715 | * @urb: urb whose transfer_buffer will be unmapped | |
716 | * | |
717 | * Reverses the effect of usb_buffer_map(). | |
718 | */ | |
719 | #if 0 | |
9251644a | 720 | void usb_buffer_unmap(struct urb *urb) |
1da177e4 LT |
721 | { |
722 | struct usb_bus *bus; | |
723 | struct device *controller; | |
724 | ||
725 | if (!urb | |
726 | || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) | |
727 | || !urb->dev | |
728 | || !(bus = urb->dev->bus) | |
729 | || !(controller = bus->controller)) | |
730 | return; | |
731 | ||
732 | if (controller->dma_mask) { | |
9251644a | 733 | dma_unmap_single(controller, |
1da177e4 | 734 | urb->transfer_dma, urb->transfer_buffer_length, |
9251644a | 735 | usb_pipein(urb->pipe) |
1da177e4 | 736 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
737 | if (usb_pipecontrol(urb->pipe)) |
738 | dma_unmap_single(controller, | |
1da177e4 | 739 | urb->setup_dma, |
9251644a | 740 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
741 | DMA_TO_DEVICE); |
742 | } | |
743 | urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP | |
744 | | URB_NO_SETUP_DMA_MAP); | |
745 | } | |
746 | #endif /* 0 */ | |
747 | ||
748 | /** | |
749 | * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint | |
750 | * @dev: device to which the scatterlist will be mapped | |
5e60a161 | 751 | * @is_in: mapping transfer direction |
1da177e4 LT |
752 | * @sg: the scatterlist to map |
753 | * @nents: the number of entries in the scatterlist | |
754 | * | |
755 | * Return value is either < 0 (indicating no buffers could be mapped), or | |
756 | * the number of DMA mapping array entries in the scatterlist. | |
757 | * | |
758 | * The caller is responsible for placing the resulting DMA addresses from | |
759 | * the scatterlist into URB transfer buffer pointers, and for setting the | |
760 | * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs. | |
761 | * | |
762 | * Top I/O rates come from queuing URBs, instead of waiting for each one | |
763 | * to complete before starting the next I/O. This is particularly easy | |
764 | * to do with scatterlists. Just allocate and submit one URB for each DMA | |
765 | * mapping entry returned, stopping on the first error or when all succeed. | |
766 | * Better yet, use the usb_sg_*() calls, which do that (and more) for you. | |
767 | * | |
768 | * This call would normally be used when translating scatterlist requests, | |
769 | * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it | |
770 | * may be able to coalesce mappings for improved I/O efficiency. | |
771 | * | |
772 | * Reverse the effect of this call with usb_buffer_unmap_sg(). | |
773 | */ | |
5e60a161 | 774 | int usb_buffer_map_sg(const struct usb_device *dev, int is_in, |
095bc335 | 775 | struct scatterlist *sg, int nents) |
1da177e4 LT |
776 | { |
777 | struct usb_bus *bus; | |
778 | struct device *controller; | |
779 | ||
780 | if (!dev | |
1da177e4 LT |
781 | || !(bus = dev->bus) |
782 | || !(controller = bus->controller) | |
783 | || !controller->dma_mask) | |
784 | return -1; | |
785 | ||
786 | // FIXME generic api broken like pci, can't report errors | |
9251644a | 787 | return dma_map_sg(controller, sg, nents, |
5e60a161 | 788 | is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
1da177e4 LT |
789 | } |
790 | ||
791 | /* XXX DISABLED, no users currently. If you wish to re-enable this | |
792 | * XXX please determine whether the sync is to transfer ownership of | |
793 | * XXX the buffer from device to cpu or vice verse, and thusly use the | |
794 | * XXX appropriate _for_{cpu,device}() method. -DaveM | |
795 | */ | |
796 | #if 0 | |
797 | ||
798 | /** | |
799 | * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s) | |
800 | * @dev: device to which the scatterlist will be mapped | |
5e60a161 | 801 | * @is_in: mapping transfer direction |
1da177e4 LT |
802 | * @sg: the scatterlist to synchronize |
803 | * @n_hw_ents: the positive return value from usb_buffer_map_sg | |
804 | * | |
805 | * Use this when you are re-using a scatterlist's data buffers for | |
806 | * another USB request. | |
807 | */ | |
5e60a161 | 808 | void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in, |
095bc335 | 809 | struct scatterlist *sg, int n_hw_ents) |
1da177e4 LT |
810 | { |
811 | struct usb_bus *bus; | |
812 | struct device *controller; | |
813 | ||
814 | if (!dev | |
815 | || !(bus = dev->bus) | |
816 | || !(controller = bus->controller) | |
817 | || !controller->dma_mask) | |
818 | return; | |
819 | ||
9251644a | 820 | dma_sync_sg(controller, sg, n_hw_ents, |
5e60a161 | 821 | is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
1da177e4 LT |
822 | } |
823 | #endif | |
824 | ||
825 | /** | |
826 | * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist | |
827 | * @dev: device to which the scatterlist will be mapped | |
5e60a161 | 828 | * @is_in: mapping transfer direction |
1da177e4 LT |
829 | * @sg: the scatterlist to unmap |
830 | * @n_hw_ents: the positive return value from usb_buffer_map_sg | |
831 | * | |
832 | * Reverses the effect of usb_buffer_map_sg(). | |
833 | */ | |
5e60a161 | 834 | void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in, |
095bc335 | 835 | struct scatterlist *sg, int n_hw_ents) |
1da177e4 LT |
836 | { |
837 | struct usb_bus *bus; | |
838 | struct device *controller; | |
839 | ||
840 | if (!dev | |
841 | || !(bus = dev->bus) | |
842 | || !(controller = bus->controller) | |
843 | || !controller->dma_mask) | |
844 | return; | |
845 | ||
9251644a | 846 | dma_unmap_sg(controller, sg, n_hw_ents, |
5e60a161 | 847 | is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
1da177e4 LT |
848 | } |
849 | ||
1da177e4 | 850 | /* format to disable USB on kernel command line is: nousb */ |
aafbf24a | 851 | __module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444); |
1da177e4 LT |
852 | |
853 | /* | |
854 | * for external read access to <nousb> | |
855 | */ | |
856 | int usb_disabled(void) | |
857 | { | |
858 | return nousb; | |
859 | } | |
860 | ||
861 | /* | |
862 | * Init | |
863 | */ | |
864 | static int __init usb_init(void) | |
865 | { | |
866 | int retval; | |
867 | if (nousb) { | |
9251644a | 868 | pr_info("%s: USB support disabled\n", usbcore_name); |
1da177e4 LT |
869 | return 0; |
870 | } | |
871 | ||
bd859281 AS |
872 | retval = ksuspend_usb_init(); |
873 | if (retval) | |
874 | goto out; | |
1da177e4 LT |
875 | retval = bus_register(&usb_bus_type); |
876 | if (retval) | |
bd859281 | 877 | goto bus_register_failed; |
1da177e4 LT |
878 | retval = usb_host_init(); |
879 | if (retval) | |
880 | goto host_init_failed; | |
881 | retval = usb_major_init(); | |
882 | if (retval) | |
883 | goto major_init_failed; | |
fbf82fd2 KS |
884 | retval = usb_register(&usbfs_driver); |
885 | if (retval) | |
886 | goto driver_register_failed; | |
9f8b17e6 | 887 | retval = usb_devio_init(); |
fbf82fd2 | 888 | if (retval) |
9f8b17e6 | 889 | goto usb_devio_init_failed; |
1da177e4 LT |
890 | retval = usbfs_init(); |
891 | if (retval) | |
892 | goto fs_init_failed; | |
893 | retval = usb_hub_init(); | |
894 | if (retval) | |
895 | goto hub_init_failed; | |
8bb54ab5 | 896 | retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE); |
1da177e4 LT |
897 | if (!retval) |
898 | goto out; | |
899 | ||
900 | usb_hub_cleanup(); | |
901 | hub_init_failed: | |
902 | usbfs_cleanup(); | |
903 | fs_init_failed: | |
9f8b17e6 KS |
904 | usb_devio_cleanup(); |
905 | usb_devio_init_failed: | |
fbf82fd2 KS |
906 | usb_deregister(&usbfs_driver); |
907 | driver_register_failed: | |
908 | usb_major_cleanup(); | |
1da177e4 LT |
909 | major_init_failed: |
910 | usb_host_cleanup(); | |
911 | host_init_failed: | |
912 | bus_unregister(&usb_bus_type); | |
bd859281 AS |
913 | bus_register_failed: |
914 | ksuspend_usb_cleanup(); | |
1da177e4 LT |
915 | out: |
916 | return retval; | |
917 | } | |
918 | ||
919 | /* | |
920 | * Cleanup | |
921 | */ | |
922 | static void __exit usb_exit(void) | |
923 | { | |
924 | /* This will matter if shutdown/reboot does exitcalls. */ | |
925 | if (nousb) | |
926 | return; | |
927 | ||
8bb54ab5 | 928 | usb_deregister_device_driver(&usb_generic_driver); |
1da177e4 LT |
929 | usb_major_cleanup(); |
930 | usbfs_cleanup(); | |
fbf82fd2 | 931 | usb_deregister(&usbfs_driver); |
9f8b17e6 | 932 | usb_devio_cleanup(); |
1da177e4 LT |
933 | usb_hub_cleanup(); |
934 | usb_host_cleanup(); | |
935 | bus_unregister(&usb_bus_type); | |
bd859281 | 936 | ksuspend_usb_cleanup(); |
1da177e4 LT |
937 | } |
938 | ||
939 | subsys_initcall(usb_init); | |
940 | module_exit(usb_exit); | |
941 | ||
942 | /* | |
943 | * USB may be built into the kernel or be built as modules. | |
944 | * These symbols are exported for device (or host controller) | |
945 | * driver modules to use. | |
946 | */ | |
947 | ||
1da177e4 LT |
948 | EXPORT_SYMBOL(usb_disabled); |
949 | ||
a3fdf4eb | 950 | EXPORT_SYMBOL_GPL(usb_get_intf); |
951 | EXPORT_SYMBOL_GPL(usb_put_intf); | |
952 | ||
1da177e4 LT |
953 | EXPORT_SYMBOL(usb_put_dev); |
954 | EXPORT_SYMBOL(usb_get_dev); | |
955 | EXPORT_SYMBOL(usb_hub_tt_clear_buffer); | |
956 | ||
1da177e4 | 957 | EXPORT_SYMBOL(usb_lock_device_for_reset); |
1da177e4 | 958 | |
1da177e4 LT |
959 | EXPORT_SYMBOL(usb_find_interface); |
960 | EXPORT_SYMBOL(usb_ifnum_to_if); | |
961 | EXPORT_SYMBOL(usb_altnum_to_altsetting); | |
962 | ||
1da177e4 LT |
963 | EXPORT_SYMBOL(__usb_get_extra_descriptor); |
964 | ||
965 | EXPORT_SYMBOL(usb_find_device); | |
966 | EXPORT_SYMBOL(usb_get_current_frame_number); | |
967 | ||
9251644a ON |
968 | EXPORT_SYMBOL(usb_buffer_alloc); |
969 | EXPORT_SYMBOL(usb_buffer_free); | |
1da177e4 LT |
970 | |
971 | #if 0 | |
9251644a ON |
972 | EXPORT_SYMBOL(usb_buffer_map); |
973 | EXPORT_SYMBOL(usb_buffer_dmasync); | |
974 | EXPORT_SYMBOL(usb_buffer_unmap); | |
1da177e4 LT |
975 | #endif |
976 | ||
9251644a | 977 | EXPORT_SYMBOL(usb_buffer_map_sg); |
1da177e4 | 978 | #if 0 |
9251644a | 979 | EXPORT_SYMBOL(usb_buffer_dmasync_sg); |
1da177e4 | 980 | #endif |
9251644a | 981 | EXPORT_SYMBOL(usb_buffer_unmap_sg); |
1da177e4 LT |
982 | |
983 | MODULE_LICENSE("GPL"); |