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 LT |
24 | #include <linux/module.h> |
25 | #include <linux/string.h> | |
26 | #include <linux/bitops.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/interrupt.h> /* for in_interrupt() */ | |
29 | #include <linux/kmod.h> | |
30 | #include <linux/init.h> | |
31 | #include <linux/spinlock.h> | |
32 | #include <linux/errno.h> | |
33 | #include <linux/smp_lock.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 | |
bd859281 AS |
51 | struct workqueue_struct *ksuspend_usb_wq; /* For autosuspend */ |
52 | ||
1da177e4 | 53 | |
1da177e4 LT |
54 | /** |
55 | * usb_ifnum_to_if - get the interface object with a given interface number | |
56 | * @dev: the device whose current configuration is considered | |
57 | * @ifnum: the desired interface | |
58 | * | |
59 | * This walks the device descriptor for the currently active configuration | |
60 | * and returns a pointer to the interface with that particular interface | |
61 | * number, or null. | |
62 | * | |
63 | * Note that configuration descriptors are not required to assign interface | |
64 | * numbers sequentially, so that it would be incorrect to assume that | |
65 | * the first interface in that descriptor corresponds to interface zero. | |
66 | * This routine helps device drivers avoid such mistakes. | |
67 | * However, you should make sure that you do the right thing with any | |
68 | * alternate settings available for this interfaces. | |
69 | * | |
70 | * Don't call this function unless you are bound to one of the interfaces | |
71 | * on this device or you have locked the device! | |
72 | */ | |
095bc335 LFC |
73 | struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev, |
74 | unsigned ifnum) | |
1da177e4 LT |
75 | { |
76 | struct usb_host_config *config = dev->actconfig; | |
77 | int i; | |
78 | ||
79 | if (!config) | |
80 | return NULL; | |
81 | for (i = 0; i < config->desc.bNumInterfaces; i++) | |
82 | if (config->interface[i]->altsetting[0] | |
83 | .desc.bInterfaceNumber == ifnum) | |
84 | return config->interface[i]; | |
85 | ||
86 | return NULL; | |
87 | } | |
88 | ||
89 | /** | |
90 | * usb_altnum_to_altsetting - get the altsetting structure with a given | |
91 | * alternate setting number. | |
92 | * @intf: the interface containing the altsetting in question | |
93 | * @altnum: the desired alternate setting number | |
94 | * | |
95 | * This searches the altsetting array of the specified interface for | |
96 | * an entry with the correct bAlternateSetting value and returns a pointer | |
97 | * to that entry, or null. | |
98 | * | |
99 | * Note that altsettings need not be stored sequentially by number, so | |
100 | * it would be incorrect to assume that the first altsetting entry in | |
101 | * the array corresponds to altsetting zero. This routine helps device | |
102 | * drivers avoid such mistakes. | |
103 | * | |
104 | * Don't call this function unless you are bound to the intf interface | |
105 | * or you have locked the device! | |
106 | */ | |
095bc335 LFC |
107 | struct usb_host_interface *usb_altnum_to_altsetting(const struct usb_interface *intf, |
108 | unsigned int altnum) | |
1da177e4 LT |
109 | { |
110 | int i; | |
111 | ||
112 | for (i = 0; i < intf->num_altsetting; i++) { | |
113 | if (intf->altsetting[i].desc.bAlternateSetting == altnum) | |
114 | return &intf->altsetting[i]; | |
115 | } | |
116 | return NULL; | |
117 | } | |
118 | ||
f5691d70 PZ |
119 | struct find_interface_arg { |
120 | int minor; | |
121 | struct usb_interface *interface; | |
122 | }; | |
1da177e4 | 123 | |
6034a080 | 124 | static int __find_interface(struct device * dev, void * data) |
125 | { | |
f5691d70 PZ |
126 | struct find_interface_arg *arg = data; |
127 | struct usb_interface *intf; | |
6034a080 | 128 | |
129 | /* can't look at usb devices, only interfaces */ | |
8bb54ab5 | 130 | if (is_usb_device(dev)) |
6034a080 | 131 | return 0; |
132 | ||
133 | intf = to_usb_interface(dev); | |
f5691d70 PZ |
134 | if (intf->minor != -1 && intf->minor == arg->minor) { |
135 | arg->interface = intf; | |
6034a080 | 136 | return 1; |
137 | } | |
138 | return 0; | |
139 | } | |
140 | ||
1da177e4 LT |
141 | /** |
142 | * usb_find_interface - find usb_interface pointer for driver and device | |
143 | * @drv: the driver whose current configuration is considered | |
144 | * @minor: the minor number of the desired device | |
145 | * | |
146 | * This walks the driver device list and returns a pointer to the interface | |
147 | * with the matching minor. Note, this only works for devices that share the | |
148 | * USB major number. | |
149 | */ | |
150 | struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) | |
151 | { | |
f5691d70 | 152 | struct find_interface_arg argb; |
1b21d5e1 | 153 | int retval; |
1da177e4 | 154 | |
f5691d70 PZ |
155 | argb.minor = minor; |
156 | argb.interface = NULL; | |
1b21d5e1 GKH |
157 | /* eat the error, it will be in argb.interface */ |
158 | retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb, | |
159 | __find_interface); | |
f5691d70 | 160 | return argb.interface; |
1da177e4 LT |
161 | } |
162 | ||
1da177e4 LT |
163 | /** |
164 | * usb_release_dev - free a usb device structure when all users of it are finished. | |
165 | * @dev: device that's been disconnected | |
166 | * | |
167 | * Will be called only by the device core when all users of this usb device are | |
168 | * done. | |
169 | */ | |
170 | static void usb_release_dev(struct device *dev) | |
171 | { | |
172 | struct usb_device *udev; | |
173 | ||
174 | udev = to_usb_device(dev); | |
175 | ||
bd859281 | 176 | #ifdef CONFIG_USB_SUSPEND |
645daaab | 177 | cancel_delayed_work(&udev->autosuspend); |
bd859281 | 178 | flush_workqueue(ksuspend_usb_wq); |
645daaab | 179 | #endif |
1da177e4 | 180 | usb_destroy_configuration(udev); |
17200583 | 181 | usb_put_hcd(bus_to_hcd(udev->bus)); |
1da177e4 LT |
182 | kfree(udev->product); |
183 | kfree(udev->manufacturer); | |
184 | kfree(udev->serial); | |
185 | kfree(udev); | |
186 | } | |
187 | ||
645daaab AS |
188 | #ifdef CONFIG_PM |
189 | ||
bd859281 AS |
190 | static int ksuspend_usb_init(void) |
191 | { | |
192 | ksuspend_usb_wq = create_singlethread_workqueue("ksuspend_usbd"); | |
193 | if (!ksuspend_usb_wq) | |
194 | return -ENOMEM; | |
195 | return 0; | |
196 | } | |
197 | ||
198 | static void ksuspend_usb_cleanup(void) | |
199 | { | |
200 | destroy_workqueue(ksuspend_usb_wq); | |
201 | } | |
202 | ||
203 | #else | |
204 | ||
205 | #define ksuspend_usb_init() 0 | |
206 | #define ksuspend_usb_cleanup() do {} while (0) | |
207 | ||
208 | #endif | |
209 | ||
210 | #ifdef CONFIG_USB_SUSPEND | |
211 | ||
645daaab AS |
212 | /* usb_autosuspend_work - callback routine to autosuspend a USB device */ |
213 | static void usb_autosuspend_work(void *_udev) | |
214 | { | |
215 | struct usb_device *udev = _udev; | |
216 | ||
e0318ebf | 217 | usb_pm_lock(udev); |
645daaab AS |
218 | udev->auto_pm = 1; |
219 | usb_suspend_both(udev, PMSG_SUSPEND); | |
e0318ebf | 220 | usb_pm_unlock(udev); |
645daaab AS |
221 | } |
222 | ||
bd859281 AS |
223 | #else |
224 | ||
225 | static void usb_autosuspend_work(void *_udev) | |
226 | {} | |
227 | ||
645daaab AS |
228 | #endif |
229 | ||
1da177e4 LT |
230 | /** |
231 | * usb_alloc_dev - usb device constructor (usbcore-internal) | |
232 | * @parent: hub to which device is connected; null to allocate a root hub | |
233 | * @bus: bus used to access the device | |
234 | * @port1: one-based index of port; ignored for root hubs | |
235 | * Context: !in_interrupt () | |
236 | * | |
237 | * Only hub drivers (including virtual root hub drivers for host | |
238 | * controllers) should ever call this. | |
239 | * | |
240 | * This call may not be used in a non-sleeping context. | |
241 | */ | |
242 | struct usb_device * | |
243 | usb_alloc_dev(struct usb_device *parent, struct usb_bus *bus, unsigned port1) | |
244 | { | |
245 | struct usb_device *dev; | |
246 | ||
0a1ef3b5 | 247 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
1da177e4 LT |
248 | if (!dev) |
249 | return NULL; | |
250 | ||
17200583 | 251 | if (!usb_get_hcd(bus_to_hcd(bus))) { |
1da177e4 LT |
252 | kfree(dev); |
253 | return NULL; | |
254 | } | |
255 | ||
256 | device_initialize(&dev->dev); | |
257 | dev->dev.bus = &usb_bus_type; | |
258 | dev->dev.dma_mask = bus->controller->dma_mask; | |
1da177e4 LT |
259 | dev->dev.release = usb_release_dev; |
260 | dev->state = USB_STATE_ATTACHED; | |
261 | ||
8bb54ab5 AS |
262 | /* This magic assignment distinguishes devices from interfaces */ |
263 | dev->dev.platform_data = &usb_generic_driver; | |
264 | ||
1da177e4 LT |
265 | INIT_LIST_HEAD(&dev->ep0.urb_list); |
266 | dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE; | |
267 | dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT; | |
268 | /* ep0 maxpacket comes later, from device descriptor */ | |
269 | dev->ep_in[0] = dev->ep_out[0] = &dev->ep0; | |
270 | ||
271 | /* Save readable and stable topology id, distinguishing devices | |
272 | * by location for diagnostics, tools, driver model, etc. The | |
273 | * string is a path along hub ports, from the root. Each device's | |
274 | * dev->devpath will be stable until USB is re-cabled, and hubs | |
275 | * are often labeled with these port numbers. The bus_id isn't | |
276 | * as stable: bus->busnum changes easily from modprobe order, | |
277 | * cardbus or pci hotplugging, and so on. | |
278 | */ | |
279 | if (unlikely (!parent)) { | |
280 | dev->devpath [0] = '0'; | |
281 | ||
282 | dev->dev.parent = bus->controller; | |
283 | sprintf (&dev->dev.bus_id[0], "usb%d", bus->busnum); | |
284 | } else { | |
285 | /* match any labeling on the hubs; it's one-based */ | |
286 | if (parent->devpath [0] == '0') | |
287 | snprintf (dev->devpath, sizeof dev->devpath, | |
288 | "%d", port1); | |
289 | else | |
290 | snprintf (dev->devpath, sizeof dev->devpath, | |
291 | "%s.%d", parent->devpath, port1); | |
292 | ||
293 | dev->dev.parent = &parent->dev; | |
294 | sprintf (&dev->dev.bus_id[0], "%d-%s", | |
295 | bus->busnum, dev->devpath); | |
296 | ||
297 | /* hub driver sets up TT records */ | |
298 | } | |
299 | ||
12c3da34 | 300 | dev->portnum = port1; |
1da177e4 LT |
301 | dev->bus = bus; |
302 | dev->parent = parent; | |
303 | INIT_LIST_HEAD(&dev->filelist); | |
304 | ||
645daaab AS |
305 | #ifdef CONFIG_PM |
306 | mutex_init(&dev->pm_mutex); | |
307 | INIT_WORK(&dev->autosuspend, usb_autosuspend_work, dev); | |
308 | #endif | |
1da177e4 LT |
309 | return dev; |
310 | } | |
311 | ||
312 | /** | |
313 | * usb_get_dev - increments the reference count of the usb device structure | |
314 | * @dev: the device being referenced | |
315 | * | |
316 | * Each live reference to a device should be refcounted. | |
317 | * | |
318 | * Drivers for USB interfaces should normally record such references in | |
319 | * their probe() methods, when they bind to an interface, and release | |
320 | * them by calling usb_put_dev(), in their disconnect() methods. | |
321 | * | |
322 | * A pointer to the device with the incremented reference counter is returned. | |
323 | */ | |
324 | struct usb_device *usb_get_dev(struct usb_device *dev) | |
325 | { | |
326 | if (dev) | |
327 | get_device(&dev->dev); | |
328 | return dev; | |
329 | } | |
330 | ||
331 | /** | |
332 | * usb_put_dev - release a use of the usb device structure | |
333 | * @dev: device that's been disconnected | |
334 | * | |
335 | * Must be called when a user of a device is finished with it. When the last | |
336 | * user of the device calls this function, the memory of the device is freed. | |
337 | */ | |
338 | void usb_put_dev(struct usb_device *dev) | |
339 | { | |
340 | if (dev) | |
341 | put_device(&dev->dev); | |
342 | } | |
343 | ||
344 | /** | |
345 | * usb_get_intf - increments the reference count of the usb interface structure | |
346 | * @intf: the interface being referenced | |
347 | * | |
348 | * Each live reference to a interface must be refcounted. | |
349 | * | |
350 | * Drivers for USB interfaces should normally record such references in | |
351 | * their probe() methods, when they bind to an interface, and release | |
352 | * them by calling usb_put_intf(), in their disconnect() methods. | |
353 | * | |
354 | * A pointer to the interface with the incremented reference counter is | |
355 | * returned. | |
356 | */ | |
357 | struct usb_interface *usb_get_intf(struct usb_interface *intf) | |
358 | { | |
359 | if (intf) | |
360 | get_device(&intf->dev); | |
361 | return intf; | |
362 | } | |
363 | ||
364 | /** | |
365 | * usb_put_intf - release a use of the usb interface structure | |
366 | * @intf: interface that's been decremented | |
367 | * | |
368 | * Must be called when a user of an interface is finished with it. When the | |
369 | * last user of the interface calls this function, the memory of the interface | |
370 | * is freed. | |
371 | */ | |
372 | void usb_put_intf(struct usb_interface *intf) | |
373 | { | |
374 | if (intf) | |
375 | put_device(&intf->dev); | |
376 | } | |
377 | ||
378 | ||
379 | /* USB device locking | |
380 | * | |
9ad3d6cc AS |
381 | * USB devices and interfaces are locked using the semaphore in their |
382 | * embedded struct device. The hub driver guarantees that whenever a | |
383 | * device is connected or disconnected, drivers are called with the | |
384 | * USB device locked as well as their particular interface. | |
1da177e4 LT |
385 | * |
386 | * Complications arise when several devices are to be locked at the same | |
387 | * time. Only hub-aware drivers that are part of usbcore ever have to | |
9ad3d6cc AS |
388 | * do this; nobody else needs to worry about it. The rule for locking |
389 | * is simple: | |
1da177e4 LT |
390 | * |
391 | * When locking both a device and its parent, always lock the | |
392 | * the parent first. | |
393 | */ | |
394 | ||
1da177e4 LT |
395 | /** |
396 | * usb_lock_device_for_reset - cautiously acquire the lock for a | |
397 | * usb device structure | |
398 | * @udev: device that's being locked | |
399 | * @iface: interface bound to the driver making the request (optional) | |
400 | * | |
401 | * Attempts to acquire the device lock, but fails if the device is | |
402 | * NOTATTACHED or SUSPENDED, or if iface is specified and the interface | |
403 | * is neither BINDING nor BOUND. Rather than sleeping to wait for the | |
404 | * lock, the routine polls repeatedly. This is to prevent deadlock with | |
405 | * disconnect; in some drivers (such as usb-storage) the disconnect() | |
3ea15966 | 406 | * or suspend() method will block waiting for a device reset to complete. |
1da177e4 LT |
407 | * |
408 | * Returns a negative error code for failure, otherwise 1 or 0 to indicate | |
409 | * that the device will or will not have to be unlocked. (0 can be | |
410 | * returned when an interface is given and is BINDING, because in that | |
411 | * case the driver already owns the device lock.) | |
412 | */ | |
413 | int usb_lock_device_for_reset(struct usb_device *udev, | |
095bc335 | 414 | const struct usb_interface *iface) |
1da177e4 | 415 | { |
3ea15966 AS |
416 | unsigned long jiffies_expire = jiffies + HZ; |
417 | ||
1da177e4 LT |
418 | if (udev->state == USB_STATE_NOTATTACHED) |
419 | return -ENODEV; | |
420 | if (udev->state == USB_STATE_SUSPENDED) | |
421 | return -EHOSTUNREACH; | |
422 | if (iface) { | |
423 | switch (iface->condition) { | |
424 | case USB_INTERFACE_BINDING: | |
425 | return 0; | |
426 | case USB_INTERFACE_BOUND: | |
427 | break; | |
428 | default: | |
429 | return -EINTR; | |
430 | } | |
431 | } | |
432 | ||
9ad3d6cc | 433 | while (usb_trylock_device(udev) != 0) { |
3ea15966 AS |
434 | |
435 | /* If we can't acquire the lock after waiting one second, | |
436 | * we're probably deadlocked */ | |
437 | if (time_after(jiffies, jiffies_expire)) | |
438 | return -EBUSY; | |
439 | ||
1da177e4 LT |
440 | msleep(15); |
441 | if (udev->state == USB_STATE_NOTATTACHED) | |
442 | return -ENODEV; | |
443 | if (udev->state == USB_STATE_SUSPENDED) | |
444 | return -EHOSTUNREACH; | |
445 | if (iface && iface->condition != USB_INTERFACE_BOUND) | |
446 | return -EINTR; | |
447 | } | |
448 | return 1; | |
449 | } | |
450 | ||
1da177e4 LT |
451 | |
452 | static struct usb_device *match_device(struct usb_device *dev, | |
453 | u16 vendor_id, u16 product_id) | |
454 | { | |
455 | struct usb_device *ret_dev = NULL; | |
456 | int child; | |
457 | ||
458 | dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n", | |
459 | le16_to_cpu(dev->descriptor.idVendor), | |
460 | le16_to_cpu(dev->descriptor.idProduct)); | |
461 | ||
462 | /* see if this device matches */ | |
463 | if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) && | |
464 | (product_id == le16_to_cpu(dev->descriptor.idProduct))) { | |
465 | dev_dbg (&dev->dev, "matched this device!\n"); | |
466 | ret_dev = usb_get_dev(dev); | |
467 | goto exit; | |
468 | } | |
469 | ||
470 | /* look through all of the children of this device */ | |
471 | for (child = 0; child < dev->maxchild; ++child) { | |
472 | if (dev->children[child]) { | |
9ad3d6cc | 473 | usb_lock_device(dev->children[child]); |
1da177e4 LT |
474 | ret_dev = match_device(dev->children[child], |
475 | vendor_id, product_id); | |
9ad3d6cc | 476 | usb_unlock_device(dev->children[child]); |
1da177e4 LT |
477 | if (ret_dev) |
478 | goto exit; | |
479 | } | |
480 | } | |
481 | exit: | |
482 | return ret_dev; | |
483 | } | |
484 | ||
485 | /** | |
486 | * usb_find_device - find a specific usb device in the system | |
487 | * @vendor_id: the vendor id of the device to find | |
488 | * @product_id: the product id of the device to find | |
489 | * | |
490 | * Returns a pointer to a struct usb_device if such a specified usb | |
491 | * device is present in the system currently. The usage count of the | |
492 | * device will be incremented if a device is found. Make sure to call | |
493 | * usb_put_dev() when the caller is finished with the device. | |
494 | * | |
495 | * If a device with the specified vendor and product id is not found, | |
496 | * NULL is returned. | |
497 | */ | |
498 | struct usb_device *usb_find_device(u16 vendor_id, u16 product_id) | |
499 | { | |
500 | struct list_head *buslist; | |
501 | struct usb_bus *bus; | |
502 | struct usb_device *dev = NULL; | |
503 | ||
4186ecf8 | 504 | mutex_lock(&usb_bus_list_lock); |
1da177e4 LT |
505 | for (buslist = usb_bus_list.next; |
506 | buslist != &usb_bus_list; | |
507 | buslist = buslist->next) { | |
508 | bus = container_of(buslist, struct usb_bus, bus_list); | |
509 | if (!bus->root_hub) | |
510 | continue; | |
511 | usb_lock_device(bus->root_hub); | |
512 | dev = match_device(bus->root_hub, vendor_id, product_id); | |
513 | usb_unlock_device(bus->root_hub); | |
514 | if (dev) | |
515 | goto exit; | |
516 | } | |
517 | exit: | |
4186ecf8 | 518 | mutex_unlock(&usb_bus_list_lock); |
1da177e4 LT |
519 | return dev; |
520 | } | |
521 | ||
522 | /** | |
523 | * usb_get_current_frame_number - return current bus frame number | |
524 | * @dev: the device whose bus is being queried | |
525 | * | |
526 | * Returns the current frame number for the USB host controller | |
527 | * used with the given USB device. This can be used when scheduling | |
528 | * isochronous requests. | |
529 | * | |
530 | * Note that different kinds of host controller have different | |
531 | * "scheduling horizons". While one type might support scheduling only | |
532 | * 32 frames into the future, others could support scheduling up to | |
533 | * 1024 frames into the future. | |
534 | */ | |
535 | int usb_get_current_frame_number(struct usb_device *dev) | |
536 | { | |
a6d2bb9f | 537 | return usb_hcd_get_frame_number (dev); |
1da177e4 LT |
538 | } |
539 | ||
540 | /*-------------------------------------------------------------------*/ | |
541 | /* | |
542 | * __usb_get_extra_descriptor() finds a descriptor of specific type in the | |
543 | * extra field of the interface and endpoint descriptor structs. | |
544 | */ | |
545 | ||
546 | int __usb_get_extra_descriptor(char *buffer, unsigned size, | |
547 | unsigned char type, void **ptr) | |
548 | { | |
549 | struct usb_descriptor_header *header; | |
550 | ||
551 | while (size >= sizeof(struct usb_descriptor_header)) { | |
552 | header = (struct usb_descriptor_header *)buffer; | |
553 | ||
554 | if (header->bLength < 2) { | |
555 | printk(KERN_ERR | |
556 | "%s: bogus descriptor, type %d length %d\n", | |
557 | usbcore_name, | |
558 | header->bDescriptorType, | |
559 | header->bLength); | |
560 | return -1; | |
561 | } | |
562 | ||
563 | if (header->bDescriptorType == type) { | |
564 | *ptr = header; | |
565 | return 0; | |
566 | } | |
567 | ||
568 | buffer += header->bLength; | |
569 | size -= header->bLength; | |
570 | } | |
571 | return -1; | |
572 | } | |
573 | ||
574 | /** | |
575 | * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP | |
576 | * @dev: device the buffer will be used with | |
577 | * @size: requested buffer size | |
578 | * @mem_flags: affect whether allocation may block | |
579 | * @dma: used to return DMA address of buffer | |
580 | * | |
581 | * Return value is either null (indicating no buffer could be allocated), or | |
582 | * the cpu-space pointer to a buffer that may be used to perform DMA to the | |
583 | * specified device. Such cpu-space buffers are returned along with the DMA | |
584 | * address (through the pointer provided). | |
585 | * | |
586 | * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags | |
587 | * to avoid behaviors like using "DMA bounce buffers", or tying down I/O | |
588 | * mapping hardware for long idle periods. The implementation varies between | |
589 | * platforms, depending on details of how DMA will work to this device. | |
590 | * Using these buffers also helps prevent cacheline sharing problems on | |
591 | * architectures where CPU caches are not DMA-coherent. | |
592 | * | |
593 | * When the buffer is no longer used, free it with usb_buffer_free(). | |
594 | */ | |
595 | void *usb_buffer_alloc ( | |
596 | struct usb_device *dev, | |
597 | size_t size, | |
55016f10 | 598 | gfp_t mem_flags, |
1da177e4 LT |
599 | dma_addr_t *dma |
600 | ) | |
601 | { | |
a6d2bb9f | 602 | if (!dev || !dev->bus) |
1da177e4 | 603 | return NULL; |
a6d2bb9f | 604 | return hcd_buffer_alloc (dev->bus, size, mem_flags, dma); |
1da177e4 LT |
605 | } |
606 | ||
607 | /** | |
608 | * usb_buffer_free - free memory allocated with usb_buffer_alloc() | |
609 | * @dev: device the buffer was used with | |
610 | * @size: requested buffer size | |
611 | * @addr: CPU address of buffer | |
612 | * @dma: DMA address of buffer | |
613 | * | |
614 | * This reclaims an I/O buffer, letting it be reused. The memory must have | |
615 | * been allocated using usb_buffer_alloc(), and the parameters must match | |
616 | * those provided in that allocation request. | |
617 | */ | |
618 | void usb_buffer_free ( | |
619 | struct usb_device *dev, | |
620 | size_t size, | |
621 | void *addr, | |
622 | dma_addr_t dma | |
623 | ) | |
624 | { | |
a6d2bb9f | 625 | if (!dev || !dev->bus) |
b94badbb DT |
626 | return; |
627 | if (!addr) | |
628 | return; | |
a6d2bb9f | 629 | hcd_buffer_free (dev->bus, size, addr, dma); |
1da177e4 LT |
630 | } |
631 | ||
632 | /** | |
633 | * usb_buffer_map - create DMA mapping(s) for an urb | |
634 | * @urb: urb whose transfer_buffer/setup_packet will be mapped | |
635 | * | |
636 | * Return value is either null (indicating no buffer could be mapped), or | |
637 | * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are | |
638 | * added to urb->transfer_flags if the operation succeeds. If the device | |
639 | * is connected to this system through a non-DMA controller, this operation | |
640 | * always succeeds. | |
641 | * | |
642 | * This call would normally be used for an urb which is reused, perhaps | |
643 | * as the target of a large periodic transfer, with usb_buffer_dmasync() | |
644 | * calls to synchronize memory and dma state. | |
645 | * | |
646 | * Reverse the effect of this call with usb_buffer_unmap(). | |
647 | */ | |
648 | #if 0 | |
649 | struct urb *usb_buffer_map (struct urb *urb) | |
650 | { | |
651 | struct usb_bus *bus; | |
652 | struct device *controller; | |
653 | ||
654 | if (!urb | |
655 | || !urb->dev | |
656 | || !(bus = urb->dev->bus) | |
657 | || !(controller = bus->controller)) | |
658 | return NULL; | |
659 | ||
660 | if (controller->dma_mask) { | |
661 | urb->transfer_dma = dma_map_single (controller, | |
662 | urb->transfer_buffer, urb->transfer_buffer_length, | |
663 | usb_pipein (urb->pipe) | |
664 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
665 | if (usb_pipecontrol (urb->pipe)) | |
666 | urb->setup_dma = dma_map_single (controller, | |
667 | urb->setup_packet, | |
668 | sizeof (struct usb_ctrlrequest), | |
669 | DMA_TO_DEVICE); | |
670 | // FIXME generic api broken like pci, can't report errors | |
671 | // if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; | |
672 | } else | |
673 | urb->transfer_dma = ~0; | |
674 | urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | |
675 | | URB_NO_SETUP_DMA_MAP); | |
676 | return urb; | |
677 | } | |
678 | #endif /* 0 */ | |
679 | ||
680 | /* XXX DISABLED, no users currently. If you wish to re-enable this | |
681 | * XXX please determine whether the sync is to transfer ownership of | |
682 | * XXX the buffer from device to cpu or vice verse, and thusly use the | |
683 | * XXX appropriate _for_{cpu,device}() method. -DaveM | |
684 | */ | |
685 | #if 0 | |
686 | ||
687 | /** | |
688 | * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s) | |
689 | * @urb: urb whose transfer_buffer/setup_packet will be synchronized | |
690 | */ | |
691 | void usb_buffer_dmasync (struct urb *urb) | |
692 | { | |
693 | struct usb_bus *bus; | |
694 | struct device *controller; | |
695 | ||
696 | if (!urb | |
697 | || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) | |
698 | || !urb->dev | |
699 | || !(bus = urb->dev->bus) | |
700 | || !(controller = bus->controller)) | |
701 | return; | |
702 | ||
703 | if (controller->dma_mask) { | |
704 | dma_sync_single (controller, | |
705 | urb->transfer_dma, urb->transfer_buffer_length, | |
706 | usb_pipein (urb->pipe) | |
707 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
708 | if (usb_pipecontrol (urb->pipe)) | |
709 | dma_sync_single (controller, | |
710 | urb->setup_dma, | |
711 | sizeof (struct usb_ctrlrequest), | |
712 | DMA_TO_DEVICE); | |
713 | } | |
714 | } | |
715 | #endif | |
716 | ||
717 | /** | |
718 | * usb_buffer_unmap - free DMA mapping(s) for an urb | |
719 | * @urb: urb whose transfer_buffer will be unmapped | |
720 | * | |
721 | * Reverses the effect of usb_buffer_map(). | |
722 | */ | |
723 | #if 0 | |
724 | void usb_buffer_unmap (struct urb *urb) | |
725 | { | |
726 | struct usb_bus *bus; | |
727 | struct device *controller; | |
728 | ||
729 | if (!urb | |
730 | || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP) | |
731 | || !urb->dev | |
732 | || !(bus = urb->dev->bus) | |
733 | || !(controller = bus->controller)) | |
734 | return; | |
735 | ||
736 | if (controller->dma_mask) { | |
737 | dma_unmap_single (controller, | |
738 | urb->transfer_dma, urb->transfer_buffer_length, | |
739 | usb_pipein (urb->pipe) | |
740 | ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
741 | if (usb_pipecontrol (urb->pipe)) | |
742 | dma_unmap_single (controller, | |
743 | urb->setup_dma, | |
744 | sizeof (struct usb_ctrlrequest), | |
745 | DMA_TO_DEVICE); | |
746 | } | |
747 | urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP | |
748 | | URB_NO_SETUP_DMA_MAP); | |
749 | } | |
750 | #endif /* 0 */ | |
751 | ||
752 | /** | |
753 | * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint | |
754 | * @dev: device to which the scatterlist will be mapped | |
755 | * @pipe: endpoint defining the mapping direction | |
756 | * @sg: the scatterlist to map | |
757 | * @nents: the number of entries in the scatterlist | |
758 | * | |
759 | * Return value is either < 0 (indicating no buffers could be mapped), or | |
760 | * the number of DMA mapping array entries in the scatterlist. | |
761 | * | |
762 | * The caller is responsible for placing the resulting DMA addresses from | |
763 | * the scatterlist into URB transfer buffer pointers, and for setting the | |
764 | * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs. | |
765 | * | |
766 | * Top I/O rates come from queuing URBs, instead of waiting for each one | |
767 | * to complete before starting the next I/O. This is particularly easy | |
768 | * to do with scatterlists. Just allocate and submit one URB for each DMA | |
769 | * mapping entry returned, stopping on the first error or when all succeed. | |
770 | * Better yet, use the usb_sg_*() calls, which do that (and more) for you. | |
771 | * | |
772 | * This call would normally be used when translating scatterlist requests, | |
773 | * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it | |
774 | * may be able to coalesce mappings for improved I/O efficiency. | |
775 | * | |
776 | * Reverse the effect of this call with usb_buffer_unmap_sg(). | |
777 | */ | |
095bc335 LFC |
778 | int usb_buffer_map_sg(const struct usb_device *dev, unsigned pipe, |
779 | struct scatterlist *sg, int nents) | |
1da177e4 LT |
780 | { |
781 | struct usb_bus *bus; | |
782 | struct device *controller; | |
783 | ||
784 | if (!dev | |
785 | || usb_pipecontrol (pipe) | |
786 | || !(bus = dev->bus) | |
787 | || !(controller = bus->controller) | |
788 | || !controller->dma_mask) | |
789 | return -1; | |
790 | ||
791 | // FIXME generic api broken like pci, can't report errors | |
792 | return dma_map_sg (controller, sg, nents, | |
793 | usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
794 | } | |
795 | ||
796 | /* XXX DISABLED, no users currently. If you wish to re-enable this | |
797 | * XXX please determine whether the sync is to transfer ownership of | |
798 | * XXX the buffer from device to cpu or vice verse, and thusly use the | |
799 | * XXX appropriate _for_{cpu,device}() method. -DaveM | |
800 | */ | |
801 | #if 0 | |
802 | ||
803 | /** | |
804 | * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s) | |
805 | * @dev: device to which the scatterlist will be mapped | |
806 | * @pipe: endpoint defining the mapping direction | |
807 | * @sg: the scatterlist to synchronize | |
808 | * @n_hw_ents: the positive return value from usb_buffer_map_sg | |
809 | * | |
810 | * Use this when you are re-using a scatterlist's data buffers for | |
811 | * another USB request. | |
812 | */ | |
095bc335 LFC |
813 | void usb_buffer_dmasync_sg(const struct usb_device *dev, unsigned pipe, |
814 | struct scatterlist *sg, int n_hw_ents) | |
1da177e4 LT |
815 | { |
816 | struct usb_bus *bus; | |
817 | struct device *controller; | |
818 | ||
819 | if (!dev | |
820 | || !(bus = dev->bus) | |
821 | || !(controller = bus->controller) | |
822 | || !controller->dma_mask) | |
823 | return; | |
824 | ||
825 | dma_sync_sg (controller, sg, n_hw_ents, | |
826 | usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
827 | } | |
828 | #endif | |
829 | ||
830 | /** | |
831 | * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist | |
832 | * @dev: device to which the scatterlist will be mapped | |
833 | * @pipe: endpoint defining the mapping direction | |
834 | * @sg: the scatterlist to unmap | |
835 | * @n_hw_ents: the positive return value from usb_buffer_map_sg | |
836 | * | |
837 | * Reverses the effect of usb_buffer_map_sg(). | |
838 | */ | |
095bc335 LFC |
839 | void usb_buffer_unmap_sg(const struct usb_device *dev, unsigned pipe, |
840 | struct scatterlist *sg, int n_hw_ents) | |
1da177e4 LT |
841 | { |
842 | struct usb_bus *bus; | |
843 | struct device *controller; | |
844 | ||
845 | if (!dev | |
846 | || !(bus = dev->bus) | |
847 | || !(controller = bus->controller) | |
848 | || !controller->dma_mask) | |
849 | return; | |
850 | ||
851 | dma_unmap_sg (controller, sg, n_hw_ents, | |
852 | usb_pipein (pipe) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); | |
853 | } | |
854 | ||
1da177e4 | 855 | /* format to disable USB on kernel command line is: nousb */ |
aafbf24a | 856 | __module_param_call("", nousb, param_set_bool, param_get_bool, &nousb, 0444); |
1da177e4 LT |
857 | |
858 | /* | |
859 | * for external read access to <nousb> | |
860 | */ | |
861 | int usb_disabled(void) | |
862 | { | |
863 | return nousb; | |
864 | } | |
865 | ||
866 | /* | |
867 | * Init | |
868 | */ | |
869 | static int __init usb_init(void) | |
870 | { | |
871 | int retval; | |
872 | if (nousb) { | |
873 | pr_info ("%s: USB support disabled\n", usbcore_name); | |
874 | return 0; | |
875 | } | |
876 | ||
bd859281 AS |
877 | retval = ksuspend_usb_init(); |
878 | if (retval) | |
879 | goto out; | |
1da177e4 LT |
880 | retval = bus_register(&usb_bus_type); |
881 | if (retval) | |
bd859281 | 882 | goto bus_register_failed; |
1da177e4 LT |
883 | retval = usb_host_init(); |
884 | if (retval) | |
885 | goto host_init_failed; | |
886 | retval = usb_major_init(); | |
887 | if (retval) | |
888 | goto major_init_failed; | |
fbf82fd2 KS |
889 | retval = usb_register(&usbfs_driver); |
890 | if (retval) | |
891 | goto driver_register_failed; | |
892 | retval = usbdev_init(); | |
893 | if (retval) | |
894 | goto usbdevice_init_failed; | |
1da177e4 LT |
895 | retval = usbfs_init(); |
896 | if (retval) | |
897 | goto fs_init_failed; | |
898 | retval = usb_hub_init(); | |
899 | if (retval) | |
900 | goto hub_init_failed; | |
8bb54ab5 | 901 | retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE); |
1da177e4 LT |
902 | if (!retval) |
903 | goto out; | |
904 | ||
905 | usb_hub_cleanup(); | |
906 | hub_init_failed: | |
907 | usbfs_cleanup(); | |
908 | fs_init_failed: | |
fbf82fd2 KS |
909 | usbdev_cleanup(); |
910 | usbdevice_init_failed: | |
911 | usb_deregister(&usbfs_driver); | |
912 | driver_register_failed: | |
913 | usb_major_cleanup(); | |
1da177e4 LT |
914 | major_init_failed: |
915 | usb_host_cleanup(); | |
916 | host_init_failed: | |
917 | bus_unregister(&usb_bus_type); | |
bd859281 AS |
918 | bus_register_failed: |
919 | ksuspend_usb_cleanup(); | |
1da177e4 LT |
920 | out: |
921 | return retval; | |
922 | } | |
923 | ||
924 | /* | |
925 | * Cleanup | |
926 | */ | |
927 | static void __exit usb_exit(void) | |
928 | { | |
929 | /* This will matter if shutdown/reboot does exitcalls. */ | |
930 | if (nousb) | |
931 | return; | |
932 | ||
8bb54ab5 | 933 | usb_deregister_device_driver(&usb_generic_driver); |
1da177e4 LT |
934 | usb_major_cleanup(); |
935 | usbfs_cleanup(); | |
fbf82fd2 KS |
936 | usb_deregister(&usbfs_driver); |
937 | usbdev_cleanup(); | |
1da177e4 LT |
938 | usb_hub_cleanup(); |
939 | usb_host_cleanup(); | |
940 | bus_unregister(&usb_bus_type); | |
bd859281 | 941 | ksuspend_usb_cleanup(); |
1da177e4 LT |
942 | } |
943 | ||
944 | subsys_initcall(usb_init); | |
945 | module_exit(usb_exit); | |
946 | ||
947 | /* | |
948 | * USB may be built into the kernel or be built as modules. | |
949 | * These symbols are exported for device (or host controller) | |
950 | * driver modules to use. | |
951 | */ | |
952 | ||
1da177e4 LT |
953 | EXPORT_SYMBOL(usb_disabled); |
954 | ||
a3fdf4eb | 955 | EXPORT_SYMBOL_GPL(usb_get_intf); |
956 | EXPORT_SYMBOL_GPL(usb_put_intf); | |
957 | ||
1da177e4 LT |
958 | EXPORT_SYMBOL(usb_put_dev); |
959 | EXPORT_SYMBOL(usb_get_dev); | |
960 | EXPORT_SYMBOL(usb_hub_tt_clear_buffer); | |
961 | ||
1da177e4 | 962 | EXPORT_SYMBOL(usb_lock_device_for_reset); |
1da177e4 | 963 | |
1da177e4 LT |
964 | EXPORT_SYMBOL(usb_find_interface); |
965 | EXPORT_SYMBOL(usb_ifnum_to_if); | |
966 | EXPORT_SYMBOL(usb_altnum_to_altsetting); | |
967 | ||
1da177e4 LT |
968 | EXPORT_SYMBOL(__usb_get_extra_descriptor); |
969 | ||
970 | EXPORT_SYMBOL(usb_find_device); | |
971 | EXPORT_SYMBOL(usb_get_current_frame_number); | |
972 | ||
973 | EXPORT_SYMBOL (usb_buffer_alloc); | |
974 | EXPORT_SYMBOL (usb_buffer_free); | |
975 | ||
976 | #if 0 | |
977 | EXPORT_SYMBOL (usb_buffer_map); | |
978 | EXPORT_SYMBOL (usb_buffer_dmasync); | |
979 | EXPORT_SYMBOL (usb_buffer_unmap); | |
980 | #endif | |
981 | ||
982 | EXPORT_SYMBOL (usb_buffer_map_sg); | |
983 | #if 0 | |
984 | EXPORT_SYMBOL (usb_buffer_dmasync_sg); | |
985 | #endif | |
986 | EXPORT_SYMBOL (usb_buffer_unmap_sg); | |
987 | ||
988 | MODULE_LICENSE("GPL"); |