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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> | |
34 | #include <linux/smp_lock.h> | |
1da177e4 | 35 | #include <linux/usb.h> |
4186ecf8 | 36 | #include <linux/mutex.h> |
bd859281 | 37 | #include <linux/workqueue.h> |
1da177e4 LT |
38 | |
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 | ||
1da177e4 LT |
47 | |
48 | const char *usbcore_name = "usbcore"; | |
49 | ||
50 | static int nousb; /* Disable USB when built into kernel image */ | |
1da177e4 | 51 | |
6b157c9b AS |
52 | /* Workqueue for autosuspend and for remote wakeup of root hubs */ |
53 | struct workqueue_struct *ksuspend_usb_wq; | |
bd859281 | 54 | |
b5e795f8 AS |
55 | #ifdef CONFIG_USB_SUSPEND |
56 | static int usb_autosuspend_delay = 2; /* Default delay value, | |
57 | * in seconds */ | |
eaafbc3a | 58 | module_param_named(autosuspend, usb_autosuspend_delay, int, 0644); |
b5e795f8 AS |
59 | MODULE_PARM_DESC(autosuspend, "default autosuspend delay"); |
60 | ||
61 | #else | |
62 | #define usb_autosuspend_delay 0 | |
63 | #endif | |
64 | ||
1da177e4 | 65 | |
1da177e4 LT |
66 | /** |
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 | */ | |
095bc335 LFC |
85 | struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev, |
86 | unsigned ifnum) | |
1da177e4 LT |
87 | { |
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 | */ | |
095bc335 LFC |
119 | struct usb_host_interface *usb_altnum_to_altsetting(const struct usb_interface *intf, |
120 | unsigned int altnum) | |
1da177e4 LT |
121 | { |
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 | ||
f5691d70 PZ |
131 | struct find_interface_arg { |
132 | int minor; | |
133 | struct usb_interface *interface; | |
134 | }; | |
1da177e4 | 135 | |
6034a080 PM |
136 | static int __find_interface(struct device * dev, void * data) |
137 | { | |
f5691d70 PZ |
138 | struct find_interface_arg *arg = data; |
139 | struct usb_interface *intf; | |
6034a080 PM |
140 | |
141 | /* can't look at usb devices, only interfaces */ | |
8bb54ab5 | 142 | if (is_usb_device(dev)) |
6034a080 PM |
143 | return 0; |
144 | ||
145 | intf = to_usb_interface(dev); | |
f5691d70 PZ |
146 | if (intf->minor != -1 && intf->minor == arg->minor) { |
147 | arg->interface = intf; | |
6034a080 PM |
148 | return 1; |
149 | } | |
150 | return 0; | |
151 | } | |
152 | ||
1da177e4 LT |
153 | /** |
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 | */ | |
162 | struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) | |
163 | { | |
f5691d70 | 164 | struct find_interface_arg argb; |
1b21d5e1 | 165 | int retval; |
1da177e4 | 166 | |
f5691d70 PZ |
167 | argb.minor = minor; |
168 | argb.interface = NULL; | |
1b21d5e1 GKH |
169 | /* eat the error, it will be in argb.interface */ |
170 | retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb, | |
171 | __find_interface); | |
f5691d70 | 172 | return argb.interface; |
1da177e4 LT |
173 | } |
174 | ||
1da177e4 LT |
175 | /** |
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 | */ | |
182 | static void usb_release_dev(struct device *dev) | |
183 | { | |
184 | struct usb_device *udev; | |
185 | ||
186 | udev = to_usb_device(dev); | |
187 | ||
bd859281 | 188 | #ifdef CONFIG_USB_SUSPEND |
645daaab | 189 | cancel_delayed_work(&udev->autosuspend); |
bd859281 | 190 | flush_workqueue(ksuspend_usb_wq); |
645daaab | 191 | #endif |
1da177e4 | 192 | usb_destroy_configuration(udev); |
17200583 | 193 | usb_put_hcd(bus_to_hcd(udev->bus)); |
1da177e4 LT |
194 | kfree(udev->product); |
195 | kfree(udev->manufacturer); | |
196 | kfree(udev->serial); | |
197 | kfree(udev); | |
198 | } | |
199 | ||
645daaab AS |
200 | #ifdef CONFIG_PM |
201 | ||
bd859281 AS |
202 | static 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 | ||
210 | static void ksuspend_usb_cleanup(void) | |
211 | { | |
212 | destroy_workqueue(ksuspend_usb_wq); | |
213 | } | |
214 | ||
db063507 AS |
215 | #else |
216 | ||
217 | #define ksuspend_usb_init() 0 | |
218 | #define ksuspend_usb_cleanup() do {} while (0) | |
219 | ||
220 | #endif /* CONFIG_PM */ | |
645daaab | 221 | |
1da177e4 LT |
222 | /** |
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 | |
9251644a | 227 | * Context: !in_interrupt() |
1da177e4 LT |
228 | * |
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 | */ | |
234 | struct usb_device * | |
235 | usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) | |
236 | { | |
237 | struct usb_device *dev; | |
238 | ||
0a1ef3b5 | 239 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
1da177e4 LT |
240 | if (!dev) |
241 | return NULL; | |
242 | ||
17200583 | 243 | if (!usb_get_hcd(bus_to_hcd(bus))) { |
1da177e4 LT |
244 | 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; | |
1da177e4 LT |
251 | dev->dev.release = usb_release_dev; |
252 | dev->state = USB_STATE_ATTACHED; | |
253 | ||
8bb54ab5 AS |
254 | /* This magic assignment distinguishes devices from interfaces */ |
255 | dev->dev.platform_data = &usb_generic_driver; | |
256 | ||
1da177e4 LT |
257 | 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 | */ | |
9251644a ON |
271 | if (unlikely(!parent)) { |
272 | dev->devpath[0] = '0'; | |
1da177e4 LT |
273 | |
274 | dev->dev.parent = bus->controller; | |
9251644a | 275 | sprintf(&dev->dev.bus_id[0], "usb%d", bus->busnum); |
1da177e4 LT |
276 | } else { |
277 | /* match any labeling on the hubs; it's one-based */ | |
9251644a ON |
278 | if (parent->devpath[0] == '0') |
279 | snprintf(dev->devpath, sizeof dev->devpath, | |
1da177e4 LT |
280 | "%d", port1); |
281 | else | |
9251644a | 282 | snprintf(dev->devpath, sizeof dev->devpath, |
1da177e4 LT |
283 | "%s.%d", parent->devpath, port1); |
284 | ||
285 | dev->dev.parent = &parent->dev; | |
9251644a | 286 | sprintf(&dev->dev.bus_id[0], "%d-%s", |
1da177e4 LT |
287 | bus->busnum, dev->devpath); |
288 | ||
289 | /* hub driver sets up TT records */ | |
290 | } | |
291 | ||
12c3da34 | 292 | dev->portnum = port1; |
1da177e4 LT |
293 | dev->bus = bus; |
294 | dev->parent = parent; | |
295 | INIT_LIST_HEAD(&dev->filelist); | |
296 | ||
645daaab AS |
297 | #ifdef CONFIG_PM |
298 | mutex_init(&dev->pm_mutex); | |
c4028958 | 299 | INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work); |
b5e795f8 | 300 | dev->autosuspend_delay = usb_autosuspend_delay * HZ; |
645daaab | 301 | #endif |
1da177e4 LT |
302 | 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 | */ | |
317 | struct 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 | */ | |
331 | void 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 | */ | |
350 | struct 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 | */ | |
365 | void usb_put_intf(struct usb_interface *intf) | |
366 | { | |
367 | if (intf) | |
368 | put_device(&intf->dev); | |
369 | } | |
370 | ||
371 | ||
372 | /* USB device locking | |
373 | * | |
9ad3d6cc AS |
374 | * 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. | |
1da177e4 LT |
378 | * |
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 | |
9ad3d6cc AS |
381 | * do this; nobody else needs to worry about it. The rule for locking |
382 | * is simple: | |
1da177e4 LT |
383 | * |
384 | * When locking both a device and its parent, always lock the | |
385 | * the parent first. | |
386 | */ | |
387 | ||
1da177e4 LT |
388 | /** |
389 | * 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() | |
3ea15966 | 399 | * or suspend() method will block waiting for a device reset to complete. |
1da177e4 LT |
400 | * |
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 | */ | |
406 | int usb_lock_device_for_reset(struct usb_device *udev, | |
095bc335 | 407 | const struct usb_interface *iface) |
1da177e4 | 408 | { |
3ea15966 AS |
409 | unsigned long jiffies_expire = jiffies + HZ; |
410 | ||
1da177e4 LT |
411 | 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 | ||
9ad3d6cc | 426 | while (usb_trylock_device(udev) != 0) { |
3ea15966 AS |
427 | |
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 | ||
1da177e4 LT |
433 | 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 | ||
1da177e4 LT |
444 | |
445 | static 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))) { | |
9251644a | 458 | dev_dbg(&dev->dev, "matched this device!\n"); |
1da177e4 LT |
459 | 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]) { | |
9ad3d6cc | 466 | usb_lock_device(dev->children[child]); |
1da177e4 LT |
467 | ret_dev = match_device(dev->children[child], |
468 | vendor_id, product_id); | |
9ad3d6cc | 469 | usb_unlock_device(dev->children[child]); |
1da177e4 LT |
470 | if (ret_dev) |
471 | goto exit; | |
472 | } | |
473 | } | |
474 | exit: | |
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 | */ | |
491 | struct 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 | ||
4186ecf8 | 497 | mutex_lock(&usb_bus_list_lock); |
1da177e4 LT |
498 | 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 | } | |
510 | exit: | |
4186ecf8 | 511 | mutex_unlock(&usb_bus_list_lock); |
1da177e4 LT |
512 | 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 | */ | |
528 | int usb_get_current_frame_number(struct usb_device *dev) | |
529 | { | |
9251644a | 530 | return usb_hcd_get_frame_number(dev); |
1da177e4 LT |
531 | } |
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 | ||
539 | int __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 | */ | |
9251644a | 588 | void *usb_buffer_alloc( |
1da177e4 LT |
589 | struct usb_device *dev, |
590 | size_t size, | |
55016f10 | 591 | gfp_t mem_flags, |
1da177e4 LT |
592 | dma_addr_t *dma |
593 | ) | |
594 | { | |
a6d2bb9f | 595 | if (!dev || !dev->bus) |
1da177e4 | 596 | return NULL; |
9251644a | 597 | return hcd_buffer_alloc(dev->bus, size, mem_flags, dma); |
1da177e4 LT |
598 | } |
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 | */ | |
9251644a | 611 | void usb_buffer_free( |
1da177e4 LT |
612 | struct usb_device *dev, |
613 | size_t size, | |
614 | void *addr, | |
615 | dma_addr_t dma | |
616 | ) | |
617 | { | |
a6d2bb9f | 618 | if (!dev || !dev->bus) |
b94badbb DT |
619 | return; |
620 | if (!addr) | |
621 | return; | |
9251644a | 622 | hcd_buffer_free(dev->bus, size, addr, dma); |
1da177e4 LT |
623 | } |
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 | |
9251644a | 642 | struct urb *usb_buffer_map(struct urb *urb) |
1da177e4 LT |
643 | { |
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) { | |
9251644a | 654 | urb->transfer_dma = dma_map_single(controller, |
1da177e4 | 655 | urb->transfer_buffer, urb->transfer_buffer_length, |
9251644a | 656 | usb_pipein(urb->pipe) |
1da177e4 | 657 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
658 | if (usb_pipecontrol(urb->pipe)) |
659 | urb->setup_dma = dma_map_single(controller, | |
1da177e4 | 660 | urb->setup_packet, |
9251644a | 661 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
662 | 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 | */ | |
9251644a | 684 | void usb_buffer_dmasync(struct urb *urb) |
1da177e4 LT |
685 | { |
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) { | |
9251644a | 697 | dma_sync_single(controller, |
1da177e4 | 698 | urb->transfer_dma, urb->transfer_buffer_length, |
9251644a | 699 | usb_pipein(urb->pipe) |
1da177e4 | 700 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
701 | if (usb_pipecontrol(urb->pipe)) |
702 | dma_sync_single(controller, | |
1da177e4 | 703 | urb->setup_dma, |
9251644a | 704 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
705 | 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 | |
9251644a | 717 | void usb_buffer_unmap(struct urb *urb) |
1da177e4 LT |
718 | { |
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) { | |
9251644a | 730 | dma_unmap_single(controller, |
1da177e4 | 731 | urb->transfer_dma, urb->transfer_buffer_length, |
9251644a | 732 | usb_pipein(urb->pipe) |
1da177e4 | 733 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); |
9251644a ON |
734 | if (usb_pipecontrol(urb->pipe)) |
735 | dma_unmap_single(controller, | |
1da177e4 | 736 | urb->setup_dma, |
9251644a | 737 | sizeof(struct usb_ctrlrequest), |
1da177e4 LT |
738 | 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 | */ | |
095bc335 LFC |
771 | int usb_buffer_map_sg(const struct usb_device *dev, unsigned pipe, |
772 | struct scatterlist *sg, int nents) | |
1da177e4 LT |
773 | { |
774 | struct usb_bus *bus; | |
775 | struct device *controller; | |
776 | ||
777 | if (!dev | |
9251644a | 778 | || usb_pipecontrol(pipe) |
1da177e4 LT |
779 | || !(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 | |
9251644a ON |
785 | return dma_map_sg(controller, sg, nents, |
786 | usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1da177e4 LT |
787 | } |
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 | */ | |
095bc335 LFC |
806 | void usb_buffer_dmasync_sg(const struct usb_device *dev, unsigned pipe, |
807 | struct scatterlist *sg, int n_hw_ents) | |
1da177e4 LT |
808 | { |
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 | ||
9251644a ON |
818 | dma_sync_sg(controller, sg, n_hw_ents, |
819 | usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1da177e4 LT |
820 | } |
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 | */ | |
095bc335 LFC |
832 | void usb_buffer_unmap_sg(const struct usb_device *dev, unsigned pipe, |
833 | struct scatterlist *sg, int n_hw_ents) | |
1da177e4 LT |
834 | { |
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 | ||
9251644a ON |
844 | dma_unmap_sg(controller, sg, n_hw_ents, |
845 | usb_pipein(pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
1da177e4 LT |
846 | } |
847 | ||
1da177e4 | 848 | /* format to disable USB on kernel command line is: nousb */ |
aafbf24a | 849 | __module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444); |
1da177e4 LT |
850 | |
851 | /* | |
852 | * for external read access to <nousb> | |
853 | */ | |
854 | int usb_disabled(void) | |
855 | { | |
856 | return nousb; | |
857 | } | |
858 | ||
859 | /* | |
860 | * Init | |
861 | */ | |
862 | static int __init usb_init(void) | |
863 | { | |
864 | int retval; | |
865 | if (nousb) { | |
9251644a | 866 | pr_info("%s: USB support disabled\n", usbcore_name); |
1da177e4 LT |
867 | return 0; |
868 | } | |
869 | ||
bd859281 AS |
870 | retval = ksuspend_usb_init(); |
871 | if (retval) | |
872 | goto out; | |
1da177e4 LT |
873 | retval = bus_register(&usb_bus_type); |
874 | if (retval) | |
bd859281 | 875 | goto bus_register_failed; |
1da177e4 LT |
876 | 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; | |
fbf82fd2 KS |
882 | 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; | |
1da177e4 LT |
888 | retval = usbfs_init(); |
889 | if (retval) | |
890 | goto fs_init_failed; | |
891 | retval = usb_hub_init(); | |
892 | if (retval) | |
893 | goto hub_init_failed; | |
8bb54ab5 | 894 | retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE); |
1da177e4 LT |
895 | if (!retval) |
896 | goto out; | |
897 | ||
898 | usb_hub_cleanup(); | |
899 | hub_init_failed: | |
900 | usbfs_cleanup(); | |
901 | fs_init_failed: | |
fbf82fd2 KS |
902 | usbdev_cleanup(); |
903 | usbdevice_init_failed: | |
904 | usb_deregister(&usbfs_driver); | |
905 | driver_register_failed: | |
906 | usb_major_cleanup(); | |
1da177e4 LT |
907 | major_init_failed: |
908 | usb_host_cleanup(); | |
909 | host_init_failed: | |
910 | bus_unregister(&usb_bus_type); | |
bd859281 AS |
911 | bus_register_failed: |
912 | ksuspend_usb_cleanup(); | |
1da177e4 LT |
913 | out: |
914 | return retval; | |
915 | } | |
916 | ||
917 | /* | |
918 | * Cleanup | |
919 | */ | |
920 | static void __exit usb_exit(void) | |
921 | { | |
922 | /* This will matter if shutdown/reboot does exitcalls. */ | |
923 | if (nousb) | |
924 | return; | |
925 | ||
8bb54ab5 | 926 | usb_deregister_device_driver(&usb_generic_driver); |
1da177e4 LT |
927 | usb_major_cleanup(); |
928 | usbfs_cleanup(); | |
fbf82fd2 KS |
929 | usb_deregister(&usbfs_driver); |
930 | usbdev_cleanup(); | |
1da177e4 LT |
931 | usb_hub_cleanup(); |
932 | usb_host_cleanup(); | |
933 | bus_unregister(&usb_bus_type); | |
bd859281 | 934 | ksuspend_usb_cleanup(); |
1da177e4 LT |
935 | } |
936 | ||
937 | subsys_initcall(usb_init); | |
938 | module_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 | ||
1da177e4 LT |
946 | EXPORT_SYMBOL(usb_disabled); |
947 | ||
a3fdf4eb | 948 | EXPORT_SYMBOL_GPL(usb_get_intf); |
949 | EXPORT_SYMBOL_GPL(usb_put_intf); | |
950 | ||
1da177e4 LT |
951 | EXPORT_SYMBOL(usb_put_dev); |
952 | EXPORT_SYMBOL(usb_get_dev); | |
953 | EXPORT_SYMBOL(usb_hub_tt_clear_buffer); | |
954 | ||
1da177e4 | 955 | EXPORT_SYMBOL(usb_lock_device_for_reset); |
1da177e4 | 956 | |
1da177e4 LT |
957 | EXPORT_SYMBOL(usb_find_interface); |
958 | EXPORT_SYMBOL(usb_ifnum_to_if); | |
959 | EXPORT_SYMBOL(usb_altnum_to_altsetting); | |
960 | ||
1da177e4 LT |
961 | EXPORT_SYMBOL(__usb_get_extra_descriptor); |
962 | ||
963 | EXPORT_SYMBOL(usb_find_device); | |
964 | EXPORT_SYMBOL(usb_get_current_frame_number); | |
965 | ||
9251644a ON |
966 | EXPORT_SYMBOL(usb_buffer_alloc); |
967 | EXPORT_SYMBOL(usb_buffer_free); | |
1da177e4 LT |
968 | |
969 | #if 0 | |
9251644a ON |
970 | EXPORT_SYMBOL(usb_buffer_map); |
971 | EXPORT_SYMBOL(usb_buffer_dmasync); | |
972 | EXPORT_SYMBOL(usb_buffer_unmap); | |
1da177e4 LT |
973 | #endif |
974 | ||
9251644a | 975 | EXPORT_SYMBOL(usb_buffer_map_sg); |
1da177e4 | 976 | #if 0 |
9251644a | 977 | EXPORT_SYMBOL(usb_buffer_dmasync_sg); |
1da177e4 | 978 | #endif |
9251644a | 979 | EXPORT_SYMBOL(usb_buffer_unmap_sg); |
1da177e4 LT |
980 | |
981 | MODULE_LICENSE("GPL"); |