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1da177e4 LT |
1 | /* |
2 | * message.c - synchronous message handling | |
3 | */ | |
4 | ||
5 | #include <linux/config.h> | |
6 | ||
7 | #ifdef CONFIG_USB_DEBUG | |
8 | #define DEBUG | |
9 | #else | |
10 | #undef DEBUG | |
11 | #endif | |
12 | ||
13 | #include <linux/pci.h> /* for scatterlist macros */ | |
14 | #include <linux/usb.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/init.h> | |
18 | #include <linux/mm.h> | |
19 | #include <linux/timer.h> | |
20 | #include <linux/ctype.h> | |
21 | #include <linux/device.h> | |
22 | #include <asm/byteorder.h> | |
23 | ||
24 | #include "hcd.h" /* for usbcore internals */ | |
25 | #include "usb.h" | |
26 | ||
27 | static void usb_api_blocking_completion(struct urb *urb, struct pt_regs *regs) | |
28 | { | |
29 | complete((struct completion *)urb->context); | |
30 | } | |
31 | ||
32 | ||
33 | static void timeout_kill(unsigned long data) | |
34 | { | |
35 | struct urb *urb = (struct urb *) data; | |
36 | ||
37 | usb_unlink_urb(urb); | |
38 | } | |
39 | ||
40 | // Starts urb and waits for completion or timeout | |
41 | // note that this call is NOT interruptible, while | |
42 | // many device driver i/o requests should be interruptible | |
43 | static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length) | |
44 | { | |
45 | struct completion done; | |
46 | struct timer_list timer; | |
47 | int status; | |
48 | ||
49 | init_completion(&done); | |
50 | urb->context = &done; | |
51 | urb->transfer_flags |= URB_ASYNC_UNLINK; | |
52 | urb->actual_length = 0; | |
53 | status = usb_submit_urb(urb, GFP_NOIO); | |
54 | ||
55 | if (status == 0) { | |
56 | if (timeout > 0) { | |
57 | init_timer(&timer); | |
58 | timer.expires = jiffies + msecs_to_jiffies(timeout); | |
59 | timer.data = (unsigned long)urb; | |
60 | timer.function = timeout_kill; | |
61 | /* grr. timeout _should_ include submit delays. */ | |
62 | add_timer(&timer); | |
63 | } | |
64 | wait_for_completion(&done); | |
65 | status = urb->status; | |
66 | /* note: HCDs return ETIMEDOUT for other reasons too */ | |
67 | if (status == -ECONNRESET) { | |
68 | dev_dbg(&urb->dev->dev, | |
69 | "%s timed out on ep%d%s len=%d/%d\n", | |
70 | current->comm, | |
71 | usb_pipeendpoint(urb->pipe), | |
72 | usb_pipein(urb->pipe) ? "in" : "out", | |
73 | urb->actual_length, | |
74 | urb->transfer_buffer_length | |
75 | ); | |
76 | if (urb->actual_length > 0) | |
77 | status = 0; | |
78 | else | |
79 | status = -ETIMEDOUT; | |
80 | } | |
81 | if (timeout > 0) | |
82 | del_timer_sync(&timer); | |
83 | } | |
84 | ||
85 | if (actual_length) | |
86 | *actual_length = urb->actual_length; | |
87 | usb_free_urb(urb); | |
88 | return status; | |
89 | } | |
90 | ||
91 | /*-------------------------------------------------------------------*/ | |
92 | // returns status (negative) or length (positive) | |
93 | static int usb_internal_control_msg(struct usb_device *usb_dev, | |
94 | unsigned int pipe, | |
95 | struct usb_ctrlrequest *cmd, | |
96 | void *data, int len, int timeout) | |
97 | { | |
98 | struct urb *urb; | |
99 | int retv; | |
100 | int length; | |
101 | ||
102 | urb = usb_alloc_urb(0, GFP_NOIO); | |
103 | if (!urb) | |
104 | return -ENOMEM; | |
105 | ||
106 | usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data, | |
107 | len, usb_api_blocking_completion, NULL); | |
108 | ||
109 | retv = usb_start_wait_urb(urb, timeout, &length); | |
110 | if (retv < 0) | |
111 | return retv; | |
112 | else | |
113 | return length; | |
114 | } | |
115 | ||
116 | /** | |
117 | * usb_control_msg - Builds a control urb, sends it off and waits for completion | |
118 | * @dev: pointer to the usb device to send the message to | |
119 | * @pipe: endpoint "pipe" to send the message to | |
120 | * @request: USB message request value | |
121 | * @requesttype: USB message request type value | |
122 | * @value: USB message value | |
123 | * @index: USB message index value | |
124 | * @data: pointer to the data to send | |
125 | * @size: length in bytes of the data to send | |
126 | * @timeout: time in msecs to wait for the message to complete before | |
127 | * timing out (if 0 the wait is forever) | |
128 | * Context: !in_interrupt () | |
129 | * | |
130 | * This function sends a simple control message to a specified endpoint | |
131 | * and waits for the message to complete, or timeout. | |
132 | * | |
133 | * If successful, it returns the number of bytes transferred, otherwise a negative error number. | |
134 | * | |
135 | * Don't use this function from within an interrupt context, like a | |
136 | * bottom half handler. If you need an asynchronous message, or need to send | |
137 | * a message from within interrupt context, use usb_submit_urb() | |
138 | * If a thread in your driver uses this call, make sure your disconnect() | |
139 | * method can wait for it to complete. Since you don't have a handle on | |
140 | * the URB used, you can't cancel the request. | |
141 | */ | |
142 | int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8 requesttype, | |
143 | __u16 value, __u16 index, void *data, __u16 size, int timeout) | |
144 | { | |
145 | struct usb_ctrlrequest *dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); | |
146 | int ret; | |
147 | ||
148 | if (!dr) | |
149 | return -ENOMEM; | |
150 | ||
151 | dr->bRequestType= requesttype; | |
152 | dr->bRequest = request; | |
153 | dr->wValue = cpu_to_le16p(&value); | |
154 | dr->wIndex = cpu_to_le16p(&index); | |
155 | dr->wLength = cpu_to_le16p(&size); | |
156 | ||
157 | //dbg("usb_control_msg"); | |
158 | ||
159 | ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout); | |
160 | ||
161 | kfree(dr); | |
162 | ||
163 | return ret; | |
164 | } | |
165 | ||
166 | ||
167 | /** | |
168 | * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion | |
169 | * @usb_dev: pointer to the usb device to send the message to | |
170 | * @pipe: endpoint "pipe" to send the message to | |
171 | * @data: pointer to the data to send | |
172 | * @len: length in bytes of the data to send | |
173 | * @actual_length: pointer to a location to put the actual length transferred in bytes | |
174 | * @timeout: time in msecs to wait for the message to complete before | |
175 | * timing out (if 0 the wait is forever) | |
176 | * Context: !in_interrupt () | |
177 | * | |
178 | * This function sends a simple bulk message to a specified endpoint | |
179 | * and waits for the message to complete, or timeout. | |
180 | * | |
181 | * If successful, it returns 0, otherwise a negative error number. | |
182 | * The number of actual bytes transferred will be stored in the | |
183 | * actual_length paramater. | |
184 | * | |
185 | * Don't use this function from within an interrupt context, like a | |
186 | * bottom half handler. If you need an asynchronous message, or need to | |
187 | * send a message from within interrupt context, use usb_submit_urb() | |
188 | * If a thread in your driver uses this call, make sure your disconnect() | |
189 | * method can wait for it to complete. Since you don't have a handle on | |
190 | * the URB used, you can't cancel the request. | |
191 | */ | |
192 | int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, | |
193 | void *data, int len, int *actual_length, int timeout) | |
194 | { | |
195 | struct urb *urb; | |
196 | ||
197 | if (len < 0) | |
198 | return -EINVAL; | |
199 | ||
200 | urb=usb_alloc_urb(0, GFP_KERNEL); | |
201 | if (!urb) | |
202 | return -ENOMEM; | |
203 | ||
204 | usb_fill_bulk_urb(urb, usb_dev, pipe, data, len, | |
205 | usb_api_blocking_completion, NULL); | |
206 | ||
207 | return usb_start_wait_urb(urb, timeout, actual_length); | |
208 | } | |
209 | ||
210 | /*-------------------------------------------------------------------*/ | |
211 | ||
212 | static void sg_clean (struct usb_sg_request *io) | |
213 | { | |
214 | if (io->urbs) { | |
215 | while (io->entries--) | |
216 | usb_free_urb (io->urbs [io->entries]); | |
217 | kfree (io->urbs); | |
218 | io->urbs = NULL; | |
219 | } | |
220 | if (io->dev->dev.dma_mask != NULL) | |
221 | usb_buffer_unmap_sg (io->dev, io->pipe, io->sg, io->nents); | |
222 | io->dev = NULL; | |
223 | } | |
224 | ||
225 | static void sg_complete (struct urb *urb, struct pt_regs *regs) | |
226 | { | |
227 | struct usb_sg_request *io = (struct usb_sg_request *) urb->context; | |
228 | ||
229 | spin_lock (&io->lock); | |
230 | ||
231 | /* In 2.5 we require hcds' endpoint queues not to progress after fault | |
232 | * reports, until the completion callback (this!) returns. That lets | |
233 | * device driver code (like this routine) unlink queued urbs first, | |
234 | * if it needs to, since the HC won't work on them at all. So it's | |
235 | * not possible for page N+1 to overwrite page N, and so on. | |
236 | * | |
237 | * That's only for "hard" faults; "soft" faults (unlinks) sometimes | |
238 | * complete before the HCD can get requests away from hardware, | |
239 | * though never during cleanup after a hard fault. | |
240 | */ | |
241 | if (io->status | |
242 | && (io->status != -ECONNRESET | |
243 | || urb->status != -ECONNRESET) | |
244 | && urb->actual_length) { | |
245 | dev_err (io->dev->bus->controller, | |
246 | "dev %s ep%d%s scatterlist error %d/%d\n", | |
247 | io->dev->devpath, | |
248 | usb_pipeendpoint (urb->pipe), | |
249 | usb_pipein (urb->pipe) ? "in" : "out", | |
250 | urb->status, io->status); | |
251 | // BUG (); | |
252 | } | |
253 | ||
254 | if (io->status == 0 && urb->status && urb->status != -ECONNRESET) { | |
255 | int i, found, status; | |
256 | ||
257 | io->status = urb->status; | |
258 | ||
259 | /* the previous urbs, and this one, completed already. | |
260 | * unlink pending urbs so they won't rx/tx bad data. | |
261 | * careful: unlink can sometimes be synchronous... | |
262 | */ | |
263 | spin_unlock (&io->lock); | |
264 | for (i = 0, found = 0; i < io->entries; i++) { | |
265 | if (!io->urbs [i] || !io->urbs [i]->dev) | |
266 | continue; | |
267 | if (found) { | |
268 | status = usb_unlink_urb (io->urbs [i]); | |
269 | if (status != -EINPROGRESS && status != -EBUSY) | |
270 | dev_err (&io->dev->dev, | |
271 | "%s, unlink --> %d\n", | |
272 | __FUNCTION__, status); | |
273 | } else if (urb == io->urbs [i]) | |
274 | found = 1; | |
275 | } | |
276 | spin_lock (&io->lock); | |
277 | } | |
278 | urb->dev = NULL; | |
279 | ||
280 | /* on the last completion, signal usb_sg_wait() */ | |
281 | io->bytes += urb->actual_length; | |
282 | io->count--; | |
283 | if (!io->count) | |
284 | complete (&io->complete); | |
285 | ||
286 | spin_unlock (&io->lock); | |
287 | } | |
288 | ||
289 | ||
290 | /** | |
291 | * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request | |
292 | * @io: request block being initialized. until usb_sg_wait() returns, | |
293 | * treat this as a pointer to an opaque block of memory, | |
294 | * @dev: the usb device that will send or receive the data | |
295 | * @pipe: endpoint "pipe" used to transfer the data | |
296 | * @period: polling rate for interrupt endpoints, in frames or | |
297 | * (for high speed endpoints) microframes; ignored for bulk | |
298 | * @sg: scatterlist entries | |
299 | * @nents: how many entries in the scatterlist | |
300 | * @length: how many bytes to send from the scatterlist, or zero to | |
301 | * send every byte identified in the list. | |
302 | * @mem_flags: SLAB_* flags affecting memory allocations in this call | |
303 | * | |
304 | * Returns zero for success, else a negative errno value. This initializes a | |
305 | * scatter/gather request, allocating resources such as I/O mappings and urb | |
306 | * memory (except maybe memory used by USB controller drivers). | |
307 | * | |
308 | * The request must be issued using usb_sg_wait(), which waits for the I/O to | |
309 | * complete (or to be canceled) and then cleans up all resources allocated by | |
310 | * usb_sg_init(). | |
311 | * | |
312 | * The request may be canceled with usb_sg_cancel(), either before or after | |
313 | * usb_sg_wait() is called. | |
314 | */ | |
315 | int usb_sg_init ( | |
316 | struct usb_sg_request *io, | |
317 | struct usb_device *dev, | |
318 | unsigned pipe, | |
319 | unsigned period, | |
320 | struct scatterlist *sg, | |
321 | int nents, | |
322 | size_t length, | |
323 | int mem_flags | |
324 | ) | |
325 | { | |
326 | int i; | |
327 | int urb_flags; | |
328 | int dma; | |
329 | ||
330 | if (!io || !dev || !sg | |
331 | || usb_pipecontrol (pipe) | |
332 | || usb_pipeisoc (pipe) | |
333 | || nents <= 0) | |
334 | return -EINVAL; | |
335 | ||
336 | spin_lock_init (&io->lock); | |
337 | io->dev = dev; | |
338 | io->pipe = pipe; | |
339 | io->sg = sg; | |
340 | io->nents = nents; | |
341 | ||
342 | /* not all host controllers use DMA (like the mainstream pci ones); | |
343 | * they can use PIO (sl811) or be software over another transport. | |
344 | */ | |
345 | dma = (dev->dev.dma_mask != NULL); | |
346 | if (dma) | |
347 | io->entries = usb_buffer_map_sg (dev, pipe, sg, nents); | |
348 | else | |
349 | io->entries = nents; | |
350 | ||
351 | /* initialize all the urbs we'll use */ | |
352 | if (io->entries <= 0) | |
353 | return io->entries; | |
354 | ||
355 | io->count = io->entries; | |
356 | io->urbs = kmalloc (io->entries * sizeof *io->urbs, mem_flags); | |
357 | if (!io->urbs) | |
358 | goto nomem; | |
359 | ||
360 | urb_flags = URB_ASYNC_UNLINK | URB_NO_TRANSFER_DMA_MAP | |
361 | | URB_NO_INTERRUPT; | |
362 | if (usb_pipein (pipe)) | |
363 | urb_flags |= URB_SHORT_NOT_OK; | |
364 | ||
365 | for (i = 0; i < io->entries; i++) { | |
366 | unsigned len; | |
367 | ||
368 | io->urbs [i] = usb_alloc_urb (0, mem_flags); | |
369 | if (!io->urbs [i]) { | |
370 | io->entries = i; | |
371 | goto nomem; | |
372 | } | |
373 | ||
374 | io->urbs [i]->dev = NULL; | |
375 | io->urbs [i]->pipe = pipe; | |
376 | io->urbs [i]->interval = period; | |
377 | io->urbs [i]->transfer_flags = urb_flags; | |
378 | ||
379 | io->urbs [i]->complete = sg_complete; | |
380 | io->urbs [i]->context = io; | |
381 | io->urbs [i]->status = -EINPROGRESS; | |
382 | io->urbs [i]->actual_length = 0; | |
383 | ||
384 | if (dma) { | |
385 | /* hc may use _only_ transfer_dma */ | |
386 | io->urbs [i]->transfer_dma = sg_dma_address (sg + i); | |
387 | len = sg_dma_len (sg + i); | |
388 | } else { | |
389 | /* hc may use _only_ transfer_buffer */ | |
390 | io->urbs [i]->transfer_buffer = | |
391 | page_address (sg [i].page) + sg [i].offset; | |
392 | len = sg [i].length; | |
393 | } | |
394 | ||
395 | if (length) { | |
396 | len = min_t (unsigned, len, length); | |
397 | length -= len; | |
398 | if (length == 0) | |
399 | io->entries = i + 1; | |
400 | } | |
401 | io->urbs [i]->transfer_buffer_length = len; | |
402 | } | |
403 | io->urbs [--i]->transfer_flags &= ~URB_NO_INTERRUPT; | |
404 | ||
405 | /* transaction state */ | |
406 | io->status = 0; | |
407 | io->bytes = 0; | |
408 | init_completion (&io->complete); | |
409 | return 0; | |
410 | ||
411 | nomem: | |
412 | sg_clean (io); | |
413 | return -ENOMEM; | |
414 | } | |
415 | ||
416 | ||
417 | /** | |
418 | * usb_sg_wait - synchronously execute scatter/gather request | |
419 | * @io: request block handle, as initialized with usb_sg_init(). | |
420 | * some fields become accessible when this call returns. | |
421 | * Context: !in_interrupt () | |
422 | * | |
423 | * This function blocks until the specified I/O operation completes. It | |
424 | * leverages the grouping of the related I/O requests to get good transfer | |
425 | * rates, by queueing the requests. At higher speeds, such queuing can | |
426 | * significantly improve USB throughput. | |
427 | * | |
428 | * There are three kinds of completion for this function. | |
429 | * (1) success, where io->status is zero. The number of io->bytes | |
430 | * transferred is as requested. | |
431 | * (2) error, where io->status is a negative errno value. The number | |
432 | * of io->bytes transferred before the error is usually less | |
433 | * than requested, and can be nonzero. | |
093cf723 | 434 | * (3) cancellation, a type of error with status -ECONNRESET that |
1da177e4 LT |
435 | * is initiated by usb_sg_cancel(). |
436 | * | |
437 | * When this function returns, all memory allocated through usb_sg_init() or | |
438 | * this call will have been freed. The request block parameter may still be | |
439 | * passed to usb_sg_cancel(), or it may be freed. It could also be | |
440 | * reinitialized and then reused. | |
441 | * | |
442 | * Data Transfer Rates: | |
443 | * | |
444 | * Bulk transfers are valid for full or high speed endpoints. | |
445 | * The best full speed data rate is 19 packets of 64 bytes each | |
446 | * per frame, or 1216 bytes per millisecond. | |
447 | * The best high speed data rate is 13 packets of 512 bytes each | |
448 | * per microframe, or 52 KBytes per millisecond. | |
449 | * | |
450 | * The reason to use interrupt transfers through this API would most likely | |
451 | * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond | |
452 | * could be transferred. That capability is less useful for low or full | |
453 | * speed interrupt endpoints, which allow at most one packet per millisecond, | |
454 | * of at most 8 or 64 bytes (respectively). | |
455 | */ | |
456 | void usb_sg_wait (struct usb_sg_request *io) | |
457 | { | |
458 | int i, entries = io->entries; | |
459 | ||
460 | /* queue the urbs. */ | |
461 | spin_lock_irq (&io->lock); | |
462 | for (i = 0; i < entries && !io->status; i++) { | |
463 | int retval; | |
464 | ||
465 | io->urbs [i]->dev = io->dev; | |
466 | retval = usb_submit_urb (io->urbs [i], SLAB_ATOMIC); | |
467 | ||
468 | /* after we submit, let completions or cancelations fire; | |
469 | * we handshake using io->status. | |
470 | */ | |
471 | spin_unlock_irq (&io->lock); | |
472 | switch (retval) { | |
473 | /* maybe we retrying will recover */ | |
474 | case -ENXIO: // hc didn't queue this one | |
475 | case -EAGAIN: | |
476 | case -ENOMEM: | |
477 | io->urbs[i]->dev = NULL; | |
478 | retval = 0; | |
479 | i--; | |
480 | yield (); | |
481 | break; | |
482 | ||
483 | /* no error? continue immediately. | |
484 | * | |
485 | * NOTE: to work better with UHCI (4K I/O buffer may | |
486 | * need 3K of TDs) it may be good to limit how many | |
487 | * URBs are queued at once; N milliseconds? | |
488 | */ | |
489 | case 0: | |
490 | cpu_relax (); | |
491 | break; | |
492 | ||
493 | /* fail any uncompleted urbs */ | |
494 | default: | |
495 | io->urbs [i]->dev = NULL; | |
496 | io->urbs [i]->status = retval; | |
497 | dev_dbg (&io->dev->dev, "%s, submit --> %d\n", | |
498 | __FUNCTION__, retval); | |
499 | usb_sg_cancel (io); | |
500 | } | |
501 | spin_lock_irq (&io->lock); | |
502 | if (retval && (io->status == 0 || io->status == -ECONNRESET)) | |
503 | io->status = retval; | |
504 | } | |
505 | io->count -= entries - i; | |
506 | if (io->count == 0) | |
507 | complete (&io->complete); | |
508 | spin_unlock_irq (&io->lock); | |
509 | ||
510 | /* OK, yes, this could be packaged as non-blocking. | |
511 | * So could the submit loop above ... but it's easier to | |
512 | * solve neither problem than to solve both! | |
513 | */ | |
514 | wait_for_completion (&io->complete); | |
515 | ||
516 | sg_clean (io); | |
517 | } | |
518 | ||
519 | /** | |
520 | * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait() | |
521 | * @io: request block, initialized with usb_sg_init() | |
522 | * | |
523 | * This stops a request after it has been started by usb_sg_wait(). | |
524 | * It can also prevents one initialized by usb_sg_init() from starting, | |
525 | * so that call just frees resources allocated to the request. | |
526 | */ | |
527 | void usb_sg_cancel (struct usb_sg_request *io) | |
528 | { | |
529 | unsigned long flags; | |
530 | ||
531 | spin_lock_irqsave (&io->lock, flags); | |
532 | ||
533 | /* shut everything down, if it didn't already */ | |
534 | if (!io->status) { | |
535 | int i; | |
536 | ||
537 | io->status = -ECONNRESET; | |
538 | spin_unlock (&io->lock); | |
539 | for (i = 0; i < io->entries; i++) { | |
540 | int retval; | |
541 | ||
542 | if (!io->urbs [i]->dev) | |
543 | continue; | |
544 | retval = usb_unlink_urb (io->urbs [i]); | |
545 | if (retval != -EINPROGRESS && retval != -EBUSY) | |
546 | dev_warn (&io->dev->dev, "%s, unlink --> %d\n", | |
547 | __FUNCTION__, retval); | |
548 | } | |
549 | spin_lock (&io->lock); | |
550 | } | |
551 | spin_unlock_irqrestore (&io->lock, flags); | |
552 | } | |
553 | ||
554 | /*-------------------------------------------------------------------*/ | |
555 | ||
556 | /** | |
557 | * usb_get_descriptor - issues a generic GET_DESCRIPTOR request | |
558 | * @dev: the device whose descriptor is being retrieved | |
559 | * @type: the descriptor type (USB_DT_*) | |
560 | * @index: the number of the descriptor | |
561 | * @buf: where to put the descriptor | |
562 | * @size: how big is "buf"? | |
563 | * Context: !in_interrupt () | |
564 | * | |
565 | * Gets a USB descriptor. Convenience functions exist to simplify | |
566 | * getting some types of descriptors. Use | |
567 | * usb_get_string() or usb_string() for USB_DT_STRING. | |
568 | * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG) | |
569 | * are part of the device structure. | |
570 | * In addition to a number of USB-standard descriptors, some | |
571 | * devices also use class-specific or vendor-specific descriptors. | |
572 | * | |
573 | * This call is synchronous, and may not be used in an interrupt context. | |
574 | * | |
575 | * Returns the number of bytes received on success, or else the status code | |
576 | * returned by the underlying usb_control_msg() call. | |
577 | */ | |
578 | int usb_get_descriptor(struct usb_device *dev, unsigned char type, unsigned char index, void *buf, int size) | |
579 | { | |
580 | int i; | |
581 | int result; | |
582 | ||
583 | memset(buf,0,size); // Make sure we parse really received data | |
584 | ||
585 | for (i = 0; i < 3; ++i) { | |
586 | /* retry on length 0 or stall; some devices are flakey */ | |
587 | result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), | |
588 | USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, | |
589 | (type << 8) + index, 0, buf, size, | |
590 | USB_CTRL_GET_TIMEOUT); | |
591 | if (result == 0 || result == -EPIPE) | |
592 | continue; | |
593 | if (result > 1 && ((u8 *)buf)[1] != type) { | |
594 | result = -EPROTO; | |
595 | continue; | |
596 | } | |
597 | break; | |
598 | } | |
599 | return result; | |
600 | } | |
601 | ||
602 | /** | |
603 | * usb_get_string - gets a string descriptor | |
604 | * @dev: the device whose string descriptor is being retrieved | |
605 | * @langid: code for language chosen (from string descriptor zero) | |
606 | * @index: the number of the descriptor | |
607 | * @buf: where to put the string | |
608 | * @size: how big is "buf"? | |
609 | * Context: !in_interrupt () | |
610 | * | |
611 | * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character, | |
612 | * in little-endian byte order). | |
613 | * The usb_string() function will often be a convenient way to turn | |
614 | * these strings into kernel-printable form. | |
615 | * | |
616 | * Strings may be referenced in device, configuration, interface, or other | |
617 | * descriptors, and could also be used in vendor-specific ways. | |
618 | * | |
619 | * This call is synchronous, and may not be used in an interrupt context. | |
620 | * | |
621 | * Returns the number of bytes received on success, or else the status code | |
622 | * returned by the underlying usb_control_msg() call. | |
623 | */ | |
624 | int usb_get_string(struct usb_device *dev, unsigned short langid, | |
625 | unsigned char index, void *buf, int size) | |
626 | { | |
627 | int i; | |
628 | int result; | |
629 | ||
630 | for (i = 0; i < 3; ++i) { | |
631 | /* retry on length 0 or stall; some devices are flakey */ | |
632 | result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), | |
633 | USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, | |
634 | (USB_DT_STRING << 8) + index, langid, buf, size, | |
635 | USB_CTRL_GET_TIMEOUT); | |
636 | if (!(result == 0 || result == -EPIPE)) | |
637 | break; | |
638 | } | |
639 | return result; | |
640 | } | |
641 | ||
642 | static void usb_try_string_workarounds(unsigned char *buf, int *length) | |
643 | { | |
644 | int newlength, oldlength = *length; | |
645 | ||
646 | for (newlength = 2; newlength + 1 < oldlength; newlength += 2) | |
647 | if (!isprint(buf[newlength]) || buf[newlength + 1]) | |
648 | break; | |
649 | ||
650 | if (newlength > 2) { | |
651 | buf[0] = newlength; | |
652 | *length = newlength; | |
653 | } | |
654 | } | |
655 | ||
656 | static int usb_string_sub(struct usb_device *dev, unsigned int langid, | |
657 | unsigned int index, unsigned char *buf) | |
658 | { | |
659 | int rc; | |
660 | ||
661 | /* Try to read the string descriptor by asking for the maximum | |
662 | * possible number of bytes */ | |
663 | rc = usb_get_string(dev, langid, index, buf, 255); | |
664 | ||
665 | /* If that failed try to read the descriptor length, then | |
666 | * ask for just that many bytes */ | |
667 | if (rc < 2) { | |
668 | rc = usb_get_string(dev, langid, index, buf, 2); | |
669 | if (rc == 2) | |
670 | rc = usb_get_string(dev, langid, index, buf, buf[0]); | |
671 | } | |
672 | ||
673 | if (rc >= 2) { | |
674 | if (!buf[0] && !buf[1]) | |
675 | usb_try_string_workarounds(buf, &rc); | |
676 | ||
677 | /* There might be extra junk at the end of the descriptor */ | |
678 | if (buf[0] < rc) | |
679 | rc = buf[0]; | |
680 | ||
681 | rc = rc - (rc & 1); /* force a multiple of two */ | |
682 | } | |
683 | ||
684 | if (rc < 2) | |
685 | rc = (rc < 0 ? rc : -EINVAL); | |
686 | ||
687 | return rc; | |
688 | } | |
689 | ||
690 | /** | |
691 | * usb_string - returns ISO 8859-1 version of a string descriptor | |
692 | * @dev: the device whose string descriptor is being retrieved | |
693 | * @index: the number of the descriptor | |
694 | * @buf: where to put the string | |
695 | * @size: how big is "buf"? | |
696 | * Context: !in_interrupt () | |
697 | * | |
698 | * This converts the UTF-16LE encoded strings returned by devices, from | |
699 | * usb_get_string_descriptor(), to null-terminated ISO-8859-1 encoded ones | |
700 | * that are more usable in most kernel contexts. Note that all characters | |
701 | * in the chosen descriptor that can't be encoded using ISO-8859-1 | |
702 | * are converted to the question mark ("?") character, and this function | |
703 | * chooses strings in the first language supported by the device. | |
704 | * | |
705 | * The ASCII (or, redundantly, "US-ASCII") character set is the seven-bit | |
706 | * subset of ISO 8859-1. ISO-8859-1 is the eight-bit subset of Unicode, | |
707 | * and is appropriate for use many uses of English and several other | |
708 | * Western European languages. (But it doesn't include the "Euro" symbol.) | |
709 | * | |
710 | * This call is synchronous, and may not be used in an interrupt context. | |
711 | * | |
712 | * Returns length of the string (>= 0) or usb_control_msg status (< 0). | |
713 | */ | |
714 | int usb_string(struct usb_device *dev, int index, char *buf, size_t size) | |
715 | { | |
716 | unsigned char *tbuf; | |
717 | int err; | |
718 | unsigned int u, idx; | |
719 | ||
720 | if (dev->state == USB_STATE_SUSPENDED) | |
721 | return -EHOSTUNREACH; | |
722 | if (size <= 0 || !buf || !index) | |
723 | return -EINVAL; | |
724 | buf[0] = 0; | |
725 | tbuf = kmalloc(256, GFP_KERNEL); | |
726 | if (!tbuf) | |
727 | return -ENOMEM; | |
728 | ||
729 | /* get langid for strings if it's not yet known */ | |
730 | if (!dev->have_langid) { | |
731 | err = usb_string_sub(dev, 0, 0, tbuf); | |
732 | if (err < 0) { | |
733 | dev_err (&dev->dev, | |
734 | "string descriptor 0 read error: %d\n", | |
735 | err); | |
736 | goto errout; | |
737 | } else if (err < 4) { | |
738 | dev_err (&dev->dev, "string descriptor 0 too short\n"); | |
739 | err = -EINVAL; | |
740 | goto errout; | |
741 | } else { | |
742 | dev->have_langid = -1; | |
743 | dev->string_langid = tbuf[2] | (tbuf[3]<< 8); | |
744 | /* always use the first langid listed */ | |
745 | dev_dbg (&dev->dev, "default language 0x%04x\n", | |
746 | dev->string_langid); | |
747 | } | |
748 | } | |
749 | ||
750 | err = usb_string_sub(dev, dev->string_langid, index, tbuf); | |
751 | if (err < 0) | |
752 | goto errout; | |
753 | ||
754 | size--; /* leave room for trailing NULL char in output buffer */ | |
755 | for (idx = 0, u = 2; u < err; u += 2) { | |
756 | if (idx >= size) | |
757 | break; | |
758 | if (tbuf[u+1]) /* high byte */ | |
759 | buf[idx++] = '?'; /* non ISO-8859-1 character */ | |
760 | else | |
761 | buf[idx++] = tbuf[u]; | |
762 | } | |
763 | buf[idx] = 0; | |
764 | err = idx; | |
765 | ||
766 | if (tbuf[1] != USB_DT_STRING) | |
767 | dev_dbg(&dev->dev, "wrong descriptor type %02x for string %d (\"%s\")\n", tbuf[1], index, buf); | |
768 | ||
769 | errout: | |
770 | kfree(tbuf); | |
771 | return err; | |
772 | } | |
773 | ||
774 | /* | |
775 | * usb_get_device_descriptor - (re)reads the device descriptor (usbcore) | |
776 | * @dev: the device whose device descriptor is being updated | |
777 | * @size: how much of the descriptor to read | |
778 | * Context: !in_interrupt () | |
779 | * | |
780 | * Updates the copy of the device descriptor stored in the device structure, | |
781 | * which dedicates space for this purpose. Note that several fields are | |
782 | * converted to the host CPU's byte order: the USB version (bcdUSB), and | |
783 | * vendors product and version fields (idVendor, idProduct, and bcdDevice). | |
784 | * That lets device drivers compare against non-byteswapped constants. | |
785 | * | |
786 | * Not exported, only for use by the core. If drivers really want to read | |
787 | * the device descriptor directly, they can call usb_get_descriptor() with | |
788 | * type = USB_DT_DEVICE and index = 0. | |
789 | * | |
790 | * This call is synchronous, and may not be used in an interrupt context. | |
791 | * | |
792 | * Returns the number of bytes received on success, or else the status code | |
793 | * returned by the underlying usb_control_msg() call. | |
794 | */ | |
795 | int usb_get_device_descriptor(struct usb_device *dev, unsigned int size) | |
796 | { | |
797 | struct usb_device_descriptor *desc; | |
798 | int ret; | |
799 | ||
800 | if (size > sizeof(*desc)) | |
801 | return -EINVAL; | |
802 | desc = kmalloc(sizeof(*desc), GFP_NOIO); | |
803 | if (!desc) | |
804 | return -ENOMEM; | |
805 | ||
806 | ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size); | |
807 | if (ret >= 0) | |
808 | memcpy(&dev->descriptor, desc, size); | |
809 | kfree(desc); | |
810 | return ret; | |
811 | } | |
812 | ||
813 | /** | |
814 | * usb_get_status - issues a GET_STATUS call | |
815 | * @dev: the device whose status is being checked | |
816 | * @type: USB_RECIP_*; for device, interface, or endpoint | |
817 | * @target: zero (for device), else interface or endpoint number | |
818 | * @data: pointer to two bytes of bitmap data | |
819 | * Context: !in_interrupt () | |
820 | * | |
821 | * Returns device, interface, or endpoint status. Normally only of | |
822 | * interest to see if the device is self powered, or has enabled the | |
823 | * remote wakeup facility; or whether a bulk or interrupt endpoint | |
824 | * is halted ("stalled"). | |
825 | * | |
826 | * Bits in these status bitmaps are set using the SET_FEATURE request, | |
827 | * and cleared using the CLEAR_FEATURE request. The usb_clear_halt() | |
828 | * function should be used to clear halt ("stall") status. | |
829 | * | |
830 | * This call is synchronous, and may not be used in an interrupt context. | |
831 | * | |
832 | * Returns the number of bytes received on success, or else the status code | |
833 | * returned by the underlying usb_control_msg() call. | |
834 | */ | |
835 | int usb_get_status(struct usb_device *dev, int type, int target, void *data) | |
836 | { | |
837 | int ret; | |
838 | u16 *status = kmalloc(sizeof(*status), GFP_KERNEL); | |
839 | ||
840 | if (!status) | |
841 | return -ENOMEM; | |
842 | ||
843 | ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), | |
844 | USB_REQ_GET_STATUS, USB_DIR_IN | type, 0, target, status, | |
845 | sizeof(*status), USB_CTRL_GET_TIMEOUT); | |
846 | ||
847 | *(u16 *)data = *status; | |
848 | kfree(status); | |
849 | return ret; | |
850 | } | |
851 | ||
852 | /** | |
853 | * usb_clear_halt - tells device to clear endpoint halt/stall condition | |
854 | * @dev: device whose endpoint is halted | |
855 | * @pipe: endpoint "pipe" being cleared | |
856 | * Context: !in_interrupt () | |
857 | * | |
858 | * This is used to clear halt conditions for bulk and interrupt endpoints, | |
859 | * as reported by URB completion status. Endpoints that are halted are | |
860 | * sometimes referred to as being "stalled". Such endpoints are unable | |
861 | * to transmit or receive data until the halt status is cleared. Any URBs | |
862 | * queued for such an endpoint should normally be unlinked by the driver | |
863 | * before clearing the halt condition, as described in sections 5.7.5 | |
864 | * and 5.8.5 of the USB 2.0 spec. | |
865 | * | |
866 | * Note that control and isochronous endpoints don't halt, although control | |
867 | * endpoints report "protocol stall" (for unsupported requests) using the | |
868 | * same status code used to report a true stall. | |
869 | * | |
870 | * This call is synchronous, and may not be used in an interrupt context. | |
871 | * | |
872 | * Returns zero on success, or else the status code returned by the | |
873 | * underlying usb_control_msg() call. | |
874 | */ | |
875 | int usb_clear_halt(struct usb_device *dev, int pipe) | |
876 | { | |
877 | int result; | |
878 | int endp = usb_pipeendpoint(pipe); | |
879 | ||
880 | if (usb_pipein (pipe)) | |
881 | endp |= USB_DIR_IN; | |
882 | ||
883 | /* we don't care if it wasn't halted first. in fact some devices | |
884 | * (like some ibmcam model 1 units) seem to expect hosts to make | |
885 | * this request for iso endpoints, which can't halt! | |
886 | */ | |
887 | result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), | |
888 | USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, | |
889 | USB_ENDPOINT_HALT, endp, NULL, 0, | |
890 | USB_CTRL_SET_TIMEOUT); | |
891 | ||
892 | /* don't un-halt or force to DATA0 except on success */ | |
893 | if (result < 0) | |
894 | return result; | |
895 | ||
896 | /* NOTE: seems like Microsoft and Apple don't bother verifying | |
897 | * the clear "took", so some devices could lock up if you check... | |
898 | * such as the Hagiwara FlashGate DUAL. So we won't bother. | |
899 | * | |
900 | * NOTE: make sure the logic here doesn't diverge much from | |
901 | * the copy in usb-storage, for as long as we need two copies. | |
902 | */ | |
903 | ||
904 | /* toggle was reset by the clear */ | |
905 | usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0); | |
906 | ||
907 | return 0; | |
908 | } | |
909 | ||
910 | /** | |
911 | * usb_disable_endpoint -- Disable an endpoint by address | |
912 | * @dev: the device whose endpoint is being disabled | |
913 | * @epaddr: the endpoint's address. Endpoint number for output, | |
914 | * endpoint number + USB_DIR_IN for input | |
915 | * | |
916 | * Deallocates hcd/hardware state for this endpoint ... and nukes all | |
917 | * pending urbs. | |
918 | * | |
919 | * If the HCD hasn't registered a disable() function, this sets the | |
920 | * endpoint's maxpacket size to 0 to prevent further submissions. | |
921 | */ | |
922 | void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr) | |
923 | { | |
924 | unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; | |
925 | struct usb_host_endpoint *ep; | |
926 | ||
927 | if (!dev) | |
928 | return; | |
929 | ||
930 | if (usb_endpoint_out(epaddr)) { | |
931 | ep = dev->ep_out[epnum]; | |
932 | dev->ep_out[epnum] = NULL; | |
933 | } else { | |
934 | ep = dev->ep_in[epnum]; | |
935 | dev->ep_in[epnum] = NULL; | |
936 | } | |
937 | if (ep && dev->bus && dev->bus->op && dev->bus->op->disable) | |
938 | dev->bus->op->disable(dev, ep); | |
939 | } | |
940 | ||
941 | /** | |
942 | * usb_disable_interface -- Disable all endpoints for an interface | |
943 | * @dev: the device whose interface is being disabled | |
944 | * @intf: pointer to the interface descriptor | |
945 | * | |
946 | * Disables all the endpoints for the interface's current altsetting. | |
947 | */ | |
948 | void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf) | |
949 | { | |
950 | struct usb_host_interface *alt = intf->cur_altsetting; | |
951 | int i; | |
952 | ||
953 | for (i = 0; i < alt->desc.bNumEndpoints; ++i) { | |
954 | usb_disable_endpoint(dev, | |
955 | alt->endpoint[i].desc.bEndpointAddress); | |
956 | } | |
957 | } | |
958 | ||
959 | /* | |
960 | * usb_disable_device - Disable all the endpoints for a USB device | |
961 | * @dev: the device whose endpoints are being disabled | |
962 | * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. | |
963 | * | |
964 | * Disables all the device's endpoints, potentially including endpoint 0. | |
965 | * Deallocates hcd/hardware state for the endpoints (nuking all or most | |
966 | * pending urbs) and usbcore state for the interfaces, so that usbcore | |
967 | * must usb_set_configuration() before any interfaces could be used. | |
968 | */ | |
969 | void usb_disable_device(struct usb_device *dev, int skip_ep0) | |
970 | { | |
971 | int i; | |
972 | ||
973 | dev_dbg(&dev->dev, "%s nuking %s URBs\n", __FUNCTION__, | |
974 | skip_ep0 ? "non-ep0" : "all"); | |
975 | for (i = skip_ep0; i < 16; ++i) { | |
976 | usb_disable_endpoint(dev, i); | |
977 | usb_disable_endpoint(dev, i + USB_DIR_IN); | |
978 | } | |
979 | dev->toggle[0] = dev->toggle[1] = 0; | |
980 | ||
981 | /* getting rid of interfaces will disconnect | |
982 | * any drivers bound to them (a key side effect) | |
983 | */ | |
984 | if (dev->actconfig) { | |
985 | for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { | |
986 | struct usb_interface *interface; | |
987 | ||
988 | /* remove this interface */ | |
989 | interface = dev->actconfig->interface[i]; | |
990 | dev_dbg (&dev->dev, "unregistering interface %s\n", | |
991 | interface->dev.bus_id); | |
992 | usb_remove_sysfs_intf_files(interface); | |
993 | kfree(interface->cur_altsetting->string); | |
994 | interface->cur_altsetting->string = NULL; | |
995 | device_del (&interface->dev); | |
996 | } | |
997 | ||
998 | /* Now that the interfaces are unbound, nobody should | |
999 | * try to access them. | |
1000 | */ | |
1001 | for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { | |
1002 | put_device (&dev->actconfig->interface[i]->dev); | |
1003 | dev->actconfig->interface[i] = NULL; | |
1004 | } | |
1005 | dev->actconfig = NULL; | |
1006 | if (dev->state == USB_STATE_CONFIGURED) | |
1007 | usb_set_device_state(dev, USB_STATE_ADDRESS); | |
1008 | } | |
1009 | } | |
1010 | ||
1011 | ||
1012 | /* | |
1013 | * usb_enable_endpoint - Enable an endpoint for USB communications | |
1014 | * @dev: the device whose interface is being enabled | |
1015 | * @ep: the endpoint | |
1016 | * | |
1017 | * Resets the endpoint toggle, and sets dev->ep_{in,out} pointers. | |
1018 | * For control endpoints, both the input and output sides are handled. | |
1019 | */ | |
1020 | static void | |
1021 | usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep) | |
1022 | { | |
1023 | unsigned int epaddr = ep->desc.bEndpointAddress; | |
1024 | unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; | |
1025 | int is_control; | |
1026 | ||
1027 | is_control = ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) | |
1028 | == USB_ENDPOINT_XFER_CONTROL); | |
1029 | if (usb_endpoint_out(epaddr) || is_control) { | |
1030 | usb_settoggle(dev, epnum, 1, 0); | |
1031 | dev->ep_out[epnum] = ep; | |
1032 | } | |
1033 | if (!usb_endpoint_out(epaddr) || is_control) { | |
1034 | usb_settoggle(dev, epnum, 0, 0); | |
1035 | dev->ep_in[epnum] = ep; | |
1036 | } | |
1037 | } | |
1038 | ||
1039 | /* | |
1040 | * usb_enable_interface - Enable all the endpoints for an interface | |
1041 | * @dev: the device whose interface is being enabled | |
1042 | * @intf: pointer to the interface descriptor | |
1043 | * | |
1044 | * Enables all the endpoints for the interface's current altsetting. | |
1045 | */ | |
1046 | static void usb_enable_interface(struct usb_device *dev, | |
1047 | struct usb_interface *intf) | |
1048 | { | |
1049 | struct usb_host_interface *alt = intf->cur_altsetting; | |
1050 | int i; | |
1051 | ||
1052 | for (i = 0; i < alt->desc.bNumEndpoints; ++i) | |
1053 | usb_enable_endpoint(dev, &alt->endpoint[i]); | |
1054 | } | |
1055 | ||
1056 | /** | |
1057 | * usb_set_interface - Makes a particular alternate setting be current | |
1058 | * @dev: the device whose interface is being updated | |
1059 | * @interface: the interface being updated | |
1060 | * @alternate: the setting being chosen. | |
1061 | * Context: !in_interrupt () | |
1062 | * | |
1063 | * This is used to enable data transfers on interfaces that may not | |
1064 | * be enabled by default. Not all devices support such configurability. | |
1065 | * Only the driver bound to an interface may change its setting. | |
1066 | * | |
1067 | * Within any given configuration, each interface may have several | |
1068 | * alternative settings. These are often used to control levels of | |
1069 | * bandwidth consumption. For example, the default setting for a high | |
1070 | * speed interrupt endpoint may not send more than 64 bytes per microframe, | |
1071 | * while interrupt transfers of up to 3KBytes per microframe are legal. | |
1072 | * Also, isochronous endpoints may never be part of an | |
1073 | * interface's default setting. To access such bandwidth, alternate | |
1074 | * interface settings must be made current. | |
1075 | * | |
1076 | * Note that in the Linux USB subsystem, bandwidth associated with | |
1077 | * an endpoint in a given alternate setting is not reserved until an URB | |
1078 | * is submitted that needs that bandwidth. Some other operating systems | |
1079 | * allocate bandwidth early, when a configuration is chosen. | |
1080 | * | |
1081 | * This call is synchronous, and may not be used in an interrupt context. | |
1082 | * Also, drivers must not change altsettings while urbs are scheduled for | |
1083 | * endpoints in that interface; all such urbs must first be completed | |
1084 | * (perhaps forced by unlinking). | |
1085 | * | |
1086 | * Returns zero on success, or else the status code returned by the | |
1087 | * underlying usb_control_msg() call. | |
1088 | */ | |
1089 | int usb_set_interface(struct usb_device *dev, int interface, int alternate) | |
1090 | { | |
1091 | struct usb_interface *iface; | |
1092 | struct usb_host_interface *alt; | |
1093 | int ret; | |
1094 | int manual = 0; | |
1095 | ||
1096 | if (dev->state == USB_STATE_SUSPENDED) | |
1097 | return -EHOSTUNREACH; | |
1098 | ||
1099 | iface = usb_ifnum_to_if(dev, interface); | |
1100 | if (!iface) { | |
1101 | dev_dbg(&dev->dev, "selecting invalid interface %d\n", | |
1102 | interface); | |
1103 | return -EINVAL; | |
1104 | } | |
1105 | ||
1106 | alt = usb_altnum_to_altsetting(iface, alternate); | |
1107 | if (!alt) { | |
1108 | warn("selecting invalid altsetting %d", alternate); | |
1109 | return -EINVAL; | |
1110 | } | |
1111 | ||
1112 | ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), | |
1113 | USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE, | |
1114 | alternate, interface, NULL, 0, 5000); | |
1115 | ||
1116 | /* 9.4.10 says devices don't need this and are free to STALL the | |
1117 | * request if the interface only has one alternate setting. | |
1118 | */ | |
1119 | if (ret == -EPIPE && iface->num_altsetting == 1) { | |
1120 | dev_dbg(&dev->dev, | |
1121 | "manual set_interface for iface %d, alt %d\n", | |
1122 | interface, alternate); | |
1123 | manual = 1; | |
1124 | } else if (ret < 0) | |
1125 | return ret; | |
1126 | ||
1127 | /* FIXME drivers shouldn't need to replicate/bugfix the logic here | |
1128 | * when they implement async or easily-killable versions of this or | |
1129 | * other "should-be-internal" functions (like clear_halt). | |
1130 | * should hcd+usbcore postprocess control requests? | |
1131 | */ | |
1132 | ||
1133 | /* prevent submissions using previous endpoint settings */ | |
1134 | usb_disable_interface(dev, iface); | |
1135 | ||
1da177e4 LT |
1136 | iface->cur_altsetting = alt; |
1137 | ||
1138 | /* If the interface only has one altsetting and the device didn't | |
a81e7ecc | 1139 | * accept the request, we attempt to carry out the equivalent action |
1da177e4 LT |
1140 | * by manually clearing the HALT feature for each endpoint in the |
1141 | * new altsetting. | |
1142 | */ | |
1143 | if (manual) { | |
1144 | int i; | |
1145 | ||
1146 | for (i = 0; i < alt->desc.bNumEndpoints; i++) { | |
1147 | unsigned int epaddr = | |
1148 | alt->endpoint[i].desc.bEndpointAddress; | |
1149 | unsigned int pipe = | |
1150 | __create_pipe(dev, USB_ENDPOINT_NUMBER_MASK & epaddr) | |
1151 | | (usb_endpoint_out(epaddr) ? USB_DIR_OUT : USB_DIR_IN); | |
1152 | ||
1153 | usb_clear_halt(dev, pipe); | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | /* 9.1.1.5: reset toggles for all endpoints in the new altsetting | |
1158 | * | |
1159 | * Note: | |
1160 | * Despite EP0 is always present in all interfaces/AS, the list of | |
1161 | * endpoints from the descriptor does not contain EP0. Due to its | |
1162 | * omnipresence one might expect EP0 being considered "affected" by | |
1163 | * any SetInterface request and hence assume toggles need to be reset. | |
1164 | * However, EP0 toggles are re-synced for every individual transfer | |
1165 | * during the SETUP stage - hence EP0 toggles are "don't care" here. | |
1166 | * (Likewise, EP0 never "halts" on well designed devices.) | |
1167 | */ | |
1168 | usb_enable_interface(dev, iface); | |
1169 | ||
1170 | return 0; | |
1171 | } | |
1172 | ||
1173 | /** | |
1174 | * usb_reset_configuration - lightweight device reset | |
1175 | * @dev: the device whose configuration is being reset | |
1176 | * | |
1177 | * This issues a standard SET_CONFIGURATION request to the device using | |
1178 | * the current configuration. The effect is to reset most USB-related | |
1179 | * state in the device, including interface altsettings (reset to zero), | |
1180 | * endpoint halts (cleared), and data toggle (only for bulk and interrupt | |
1181 | * endpoints). Other usbcore state is unchanged, including bindings of | |
1182 | * usb device drivers to interfaces. | |
1183 | * | |
1184 | * Because this affects multiple interfaces, avoid using this with composite | |
1185 | * (multi-interface) devices. Instead, the driver for each interface may | |
a81e7ecc DB |
1186 | * use usb_set_interface() on the interfaces it claims. Be careful though; |
1187 | * some devices don't support the SET_INTERFACE request, and others won't | |
1188 | * reset all the interface state (notably data toggles). Resetting the whole | |
1da177e4 LT |
1189 | * configuration would affect other drivers' interfaces. |
1190 | * | |
1191 | * The caller must own the device lock. | |
1192 | * | |
1193 | * Returns zero on success, else a negative error code. | |
1194 | */ | |
1195 | int usb_reset_configuration(struct usb_device *dev) | |
1196 | { | |
1197 | int i, retval; | |
1198 | struct usb_host_config *config; | |
1199 | ||
1200 | if (dev->state == USB_STATE_SUSPENDED) | |
1201 | return -EHOSTUNREACH; | |
1202 | ||
1203 | /* caller must have locked the device and must own | |
1204 | * the usb bus readlock (so driver bindings are stable); | |
1205 | * calls during probe() are fine | |
1206 | */ | |
1207 | ||
1208 | for (i = 1; i < 16; ++i) { | |
1209 | usb_disable_endpoint(dev, i); | |
1210 | usb_disable_endpoint(dev, i + USB_DIR_IN); | |
1211 | } | |
1212 | ||
1213 | config = dev->actconfig; | |
1214 | retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), | |
1215 | USB_REQ_SET_CONFIGURATION, 0, | |
1216 | config->desc.bConfigurationValue, 0, | |
1217 | NULL, 0, USB_CTRL_SET_TIMEOUT); | |
1218 | if (retval < 0) { | |
1219 | usb_set_device_state(dev, USB_STATE_ADDRESS); | |
1220 | return retval; | |
1221 | } | |
1222 | ||
1223 | dev->toggle[0] = dev->toggle[1] = 0; | |
1224 | ||
1225 | /* re-init hc/hcd interface/endpoint state */ | |
1226 | for (i = 0; i < config->desc.bNumInterfaces; i++) { | |
1227 | struct usb_interface *intf = config->interface[i]; | |
1228 | struct usb_host_interface *alt; | |
1229 | ||
1230 | alt = usb_altnum_to_altsetting(intf, 0); | |
1231 | ||
1232 | /* No altsetting 0? We'll assume the first altsetting. | |
1233 | * We could use a GetInterface call, but if a device is | |
1234 | * so non-compliant that it doesn't have altsetting 0 | |
1235 | * then I wouldn't trust its reply anyway. | |
1236 | */ | |
1237 | if (!alt) | |
1238 | alt = &intf->altsetting[0]; | |
1239 | ||
1240 | intf->cur_altsetting = alt; | |
1241 | usb_enable_interface(dev, intf); | |
1242 | } | |
1243 | return 0; | |
1244 | } | |
1245 | ||
1246 | static void release_interface(struct device *dev) | |
1247 | { | |
1248 | struct usb_interface *intf = to_usb_interface(dev); | |
1249 | struct usb_interface_cache *intfc = | |
1250 | altsetting_to_usb_interface_cache(intf->altsetting); | |
1251 | ||
1252 | kref_put(&intfc->ref, usb_release_interface_cache); | |
1253 | kfree(intf); | |
1254 | } | |
1255 | ||
1256 | /* | |
1257 | * usb_set_configuration - Makes a particular device setting be current | |
1258 | * @dev: the device whose configuration is being updated | |
1259 | * @configuration: the configuration being chosen. | |
1260 | * Context: !in_interrupt(), caller owns the device lock | |
1261 | * | |
1262 | * This is used to enable non-default device modes. Not all devices | |
1263 | * use this kind of configurability; many devices only have one | |
1264 | * configuration. | |
1265 | * | |
1266 | * USB device configurations may affect Linux interoperability, | |
1267 | * power consumption and the functionality available. For example, | |
1268 | * the default configuration is limited to using 100mA of bus power, | |
1269 | * so that when certain device functionality requires more power, | |
1270 | * and the device is bus powered, that functionality should be in some | |
1271 | * non-default device configuration. Other device modes may also be | |
1272 | * reflected as configuration options, such as whether two ISDN | |
1273 | * channels are available independently; and choosing between open | |
1274 | * standard device protocols (like CDC) or proprietary ones. | |
1275 | * | |
1276 | * Note that USB has an additional level of device configurability, | |
1277 | * associated with interfaces. That configurability is accessed using | |
1278 | * usb_set_interface(). | |
1279 | * | |
1280 | * This call is synchronous. The calling context must be able to sleep, | |
1281 | * must own the device lock, and must not hold the driver model's USB | |
1282 | * bus rwsem; usb device driver probe() methods cannot use this routine. | |
1283 | * | |
1284 | * Returns zero on success, or else the status code returned by the | |
093cf723 | 1285 | * underlying call that failed. On successful completion, each interface |
1da177e4 LT |
1286 | * in the original device configuration has been destroyed, and each one |
1287 | * in the new configuration has been probed by all relevant usb device | |
1288 | * drivers currently known to the kernel. | |
1289 | */ | |
1290 | int usb_set_configuration(struct usb_device *dev, int configuration) | |
1291 | { | |
1292 | int i, ret; | |
1293 | struct usb_host_config *cp = NULL; | |
1294 | struct usb_interface **new_interfaces = NULL; | |
1295 | int n, nintf; | |
1296 | ||
1297 | for (i = 0; i < dev->descriptor.bNumConfigurations; i++) { | |
1298 | if (dev->config[i].desc.bConfigurationValue == configuration) { | |
1299 | cp = &dev->config[i]; | |
1300 | break; | |
1301 | } | |
1302 | } | |
1303 | if ((!cp && configuration != 0)) | |
1304 | return -EINVAL; | |
1305 | ||
1306 | /* The USB spec says configuration 0 means unconfigured. | |
1307 | * But if a device includes a configuration numbered 0, | |
1308 | * we will accept it as a correctly configured state. | |
1309 | */ | |
1310 | if (cp && configuration == 0) | |
1311 | dev_warn(&dev->dev, "config 0 descriptor??\n"); | |
1312 | ||
1313 | if (dev->state == USB_STATE_SUSPENDED) | |
1314 | return -EHOSTUNREACH; | |
1315 | ||
1316 | /* Allocate memory for new interfaces before doing anything else, | |
1317 | * so that if we run out then nothing will have changed. */ | |
1318 | n = nintf = 0; | |
1319 | if (cp) { | |
1320 | nintf = cp->desc.bNumInterfaces; | |
1321 | new_interfaces = kmalloc(nintf * sizeof(*new_interfaces), | |
1322 | GFP_KERNEL); | |
1323 | if (!new_interfaces) { | |
1324 | dev_err(&dev->dev, "Out of memory"); | |
1325 | return -ENOMEM; | |
1326 | } | |
1327 | ||
1328 | for (; n < nintf; ++n) { | |
1329 | new_interfaces[n] = kmalloc( | |
1330 | sizeof(struct usb_interface), | |
1331 | GFP_KERNEL); | |
1332 | if (!new_interfaces[n]) { | |
1333 | dev_err(&dev->dev, "Out of memory"); | |
1334 | ret = -ENOMEM; | |
1335 | free_interfaces: | |
1336 | while (--n >= 0) | |
1337 | kfree(new_interfaces[n]); | |
1338 | kfree(new_interfaces); | |
1339 | return ret; | |
1340 | } | |
1341 | } | |
1342 | } | |
1343 | ||
1344 | /* if it's already configured, clear out old state first. | |
1345 | * getting rid of old interfaces means unbinding their drivers. | |
1346 | */ | |
1347 | if (dev->state != USB_STATE_ADDRESS) | |
1348 | usb_disable_device (dev, 1); // Skip ep0 | |
1349 | ||
1350 | if ((ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), | |
1351 | USB_REQ_SET_CONFIGURATION, 0, configuration, 0, | |
1352 | NULL, 0, USB_CTRL_SET_TIMEOUT)) < 0) | |
1353 | goto free_interfaces; | |
1354 | ||
1355 | dev->actconfig = cp; | |
1356 | if (!cp) | |
1357 | usb_set_device_state(dev, USB_STATE_ADDRESS); | |
1358 | else { | |
1359 | usb_set_device_state(dev, USB_STATE_CONFIGURED); | |
1360 | ||
1361 | /* Initialize the new interface structures and the | |
1362 | * hc/hcd/usbcore interface/endpoint state. | |
1363 | */ | |
1364 | for (i = 0; i < nintf; ++i) { | |
1365 | struct usb_interface_cache *intfc; | |
1366 | struct usb_interface *intf; | |
1367 | struct usb_host_interface *alt; | |
1368 | ||
1369 | cp->interface[i] = intf = new_interfaces[i]; | |
1370 | memset(intf, 0, sizeof(*intf)); | |
1371 | intfc = cp->intf_cache[i]; | |
1372 | intf->altsetting = intfc->altsetting; | |
1373 | intf->num_altsetting = intfc->num_altsetting; | |
1374 | kref_get(&intfc->ref); | |
1375 | ||
1376 | alt = usb_altnum_to_altsetting(intf, 0); | |
1377 | ||
1378 | /* No altsetting 0? We'll assume the first altsetting. | |
1379 | * We could use a GetInterface call, but if a device is | |
1380 | * so non-compliant that it doesn't have altsetting 0 | |
1381 | * then I wouldn't trust its reply anyway. | |
1382 | */ | |
1383 | if (!alt) | |
1384 | alt = &intf->altsetting[0]; | |
1385 | ||
1386 | intf->cur_altsetting = alt; | |
1387 | usb_enable_interface(dev, intf); | |
1388 | intf->dev.parent = &dev->dev; | |
1389 | intf->dev.driver = NULL; | |
1390 | intf->dev.bus = &usb_bus_type; | |
1391 | intf->dev.dma_mask = dev->dev.dma_mask; | |
1392 | intf->dev.release = release_interface; | |
1393 | device_initialize (&intf->dev); | |
1394 | sprintf (&intf->dev.bus_id[0], "%d-%s:%d.%d", | |
1395 | dev->bus->busnum, dev->devpath, | |
1396 | configuration, | |
1397 | alt->desc.bInterfaceNumber); | |
1398 | } | |
1399 | kfree(new_interfaces); | |
1400 | ||
1401 | if ((cp->desc.iConfiguration) && | |
1402 | (cp->string == NULL)) { | |
1403 | cp->string = kmalloc(256, GFP_KERNEL); | |
1404 | if (cp->string) | |
1405 | usb_string(dev, cp->desc.iConfiguration, cp->string, 256); | |
1406 | } | |
1407 | ||
1408 | /* Now that all the interfaces are set up, register them | |
1409 | * to trigger binding of drivers to interfaces. probe() | |
1410 | * routines may install different altsettings and may | |
1411 | * claim() any interfaces not yet bound. Many class drivers | |
1412 | * need that: CDC, audio, video, etc. | |
1413 | */ | |
1414 | for (i = 0; i < nintf; ++i) { | |
1415 | struct usb_interface *intf = cp->interface[i]; | |
1416 | struct usb_interface_descriptor *desc; | |
1417 | ||
1418 | desc = &intf->altsetting [0].desc; | |
1419 | dev_dbg (&dev->dev, | |
1420 | "adding %s (config #%d, interface %d)\n", | |
1421 | intf->dev.bus_id, configuration, | |
1422 | desc->bInterfaceNumber); | |
1423 | ret = device_add (&intf->dev); | |
1424 | if (ret != 0) { | |
1425 | dev_err(&dev->dev, | |
1426 | "device_add(%s) --> %d\n", | |
1427 | intf->dev.bus_id, | |
1428 | ret); | |
1429 | continue; | |
1430 | } | |
1431 | if ((intf->cur_altsetting->desc.iInterface) && | |
1432 | (intf->cur_altsetting->string == NULL)) { | |
1433 | intf->cur_altsetting->string = kmalloc(256, GFP_KERNEL); | |
1434 | if (intf->cur_altsetting->string) | |
1435 | usb_string(dev, intf->cur_altsetting->desc.iInterface, | |
1436 | intf->cur_altsetting->string, 256); | |
1437 | } | |
1438 | usb_create_sysfs_intf_files (intf); | |
1439 | } | |
1440 | } | |
1441 | ||
1442 | return ret; | |
1443 | } | |
1444 | ||
1445 | // synchronous request completion model | |
1446 | EXPORT_SYMBOL(usb_control_msg); | |
1447 | EXPORT_SYMBOL(usb_bulk_msg); | |
1448 | ||
1449 | EXPORT_SYMBOL(usb_sg_init); | |
1450 | EXPORT_SYMBOL(usb_sg_cancel); | |
1451 | EXPORT_SYMBOL(usb_sg_wait); | |
1452 | ||
1453 | // synchronous control message convenience routines | |
1454 | EXPORT_SYMBOL(usb_get_descriptor); | |
1455 | EXPORT_SYMBOL(usb_get_status); | |
1456 | EXPORT_SYMBOL(usb_get_string); | |
1457 | EXPORT_SYMBOL(usb_string); | |
1458 | ||
1459 | // synchronous calls that also maintain usbcore state | |
1460 | EXPORT_SYMBOL(usb_clear_halt); | |
1461 | EXPORT_SYMBOL(usb_reset_configuration); | |
1462 | EXPORT_SYMBOL(usb_set_interface); | |
1463 |