1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * message.c - synchronous message handling 4 * 5 * Released under the GPLv2 only. 6 */ 7 8 #include <linux/pci.h> /* for scatterlist macros */ 9 #include <linux/usb.h> 10 #include <linux/module.h> 11 #include <linux/slab.h> 12 #include <linux/mm.h> 13 #include <linux/timer.h> 14 #include <linux/ctype.h> 15 #include <linux/nls.h> 16 #include <linux/device.h> 17 #include <linux/scatterlist.h> 18 #include <linux/usb/cdc.h> 19 #include <linux/usb/quirks.h> 20 #include <linux/usb/hcd.h> /* for usbcore internals */ 21 #include <asm/byteorder.h> 22 23 #include "usb.h" 24 25 static void cancel_async_set_config(struct usb_device *udev); 26 27 struct api_context { 28 struct completion done; 29 int status; 30 }; 31 32 static void usb_api_blocking_completion(struct urb *urb) 33 { 34 struct api_context *ctx = urb->context; 35 36 ctx->status = urb->status; 37 complete(&ctx->done); 38 } 39 40 41 /* 42 * Starts urb and waits for completion or timeout. Note that this call 43 * is NOT interruptible. Many device driver i/o requests should be 44 * interruptible and therefore these drivers should implement their 45 * own interruptible routines. 46 */ 47 static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) 48 { 49 struct api_context ctx; 50 unsigned long expire; 51 int retval; 52 53 init_completion(&ctx.done); 54 urb->context = &ctx; 55 urb->actual_length = 0; 56 retval = usb_submit_urb(urb, GFP_NOIO); 57 if (unlikely(retval)) 58 goto out; 59 60 expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT; 61 if (!wait_for_completion_timeout(&ctx.done, expire)) { 62 usb_kill_urb(urb); 63 retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status); 64 65 dev_dbg(&urb->dev->dev, 66 "%s timed out on ep%d%s len=%u/%u\n", 67 current->comm, 68 usb_endpoint_num(&urb->ep->desc), 69 usb_urb_dir_in(urb) ? "in" : "out", 70 urb->actual_length, 71 urb->transfer_buffer_length); 72 } else 73 retval = ctx.status; 74 out: 75 if (actual_length) 76 *actual_length = urb->actual_length; 77 78 usb_free_urb(urb); 79 return retval; 80 } 81 82 /*-------------------------------------------------------------------*/ 83 /* returns status (negative) or length (positive) */ 84 static int usb_internal_control_msg(struct usb_device *usb_dev, 85 unsigned int pipe, 86 struct usb_ctrlrequest *cmd, 87 void *data, int len, int timeout) 88 { 89 struct urb *urb; 90 int retv; 91 int length; 92 93 urb = usb_alloc_urb(0, GFP_NOIO); 94 if (!urb) 95 return -ENOMEM; 96 97 usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data, 98 len, usb_api_blocking_completion, NULL); 99 100 retv = usb_start_wait_urb(urb, timeout, &length); 101 if (retv < 0) 102 return retv; 103 else 104 return length; 105 } 106 107 /** 108 * usb_control_msg - Builds a control urb, sends it off and waits for completion 109 * @dev: pointer to the usb device to send the message to 110 * @pipe: endpoint "pipe" to send the message to 111 * @request: USB message request value 112 * @requesttype: USB message request type value 113 * @value: USB message value 114 * @index: USB message index value 115 * @data: pointer to the data to send 116 * @size: length in bytes of the data to send 117 * @timeout: time in msecs to wait for the message to complete before timing 118 * out (if 0 the wait is forever) 119 * 120 * Context: !in_interrupt () 121 * 122 * This function sends a simple control message to a specified endpoint and 123 * waits for the message to complete, or timeout. 124 * 125 * Don't use this function from within an interrupt context. If you need 126 * an asynchronous message, or need to send a message from within interrupt 127 * context, use usb_submit_urb(). If a thread in your driver uses this call, 128 * make sure your disconnect() method can wait for it to complete. Since you 129 * don't have a handle on the URB used, you can't cancel the request. 130 * 131 * Return: If successful, the number of bytes transferred. Otherwise, a negative 132 * error number. 133 */ 134 int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, 135 __u8 requesttype, __u16 value, __u16 index, void *data, 136 __u16 size, int timeout) 137 { 138 struct usb_ctrlrequest *dr; 139 int ret; 140 141 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); 142 if (!dr) 143 return -ENOMEM; 144 145 dr->bRequestType = requesttype; 146 dr->bRequest = request; 147 dr->wValue = cpu_to_le16(value); 148 dr->wIndex = cpu_to_le16(index); 149 dr->wLength = cpu_to_le16(size); 150 151 ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout); 152 153 kfree(dr); 154 155 return ret; 156 } 157 EXPORT_SYMBOL_GPL(usb_control_msg); 158 159 /** 160 * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion 161 * @usb_dev: pointer to the usb device to send the message to 162 * @pipe: endpoint "pipe" to send the message to 163 * @data: pointer to the data to send 164 * @len: length in bytes of the data to send 165 * @actual_length: pointer to a location to put the actual length transferred 166 * in bytes 167 * @timeout: time in msecs to wait for the message to complete before 168 * timing out (if 0 the wait is forever) 169 * 170 * Context: !in_interrupt () 171 * 172 * This function sends a simple interrupt message to a specified endpoint and 173 * waits for the message to complete, or timeout. 174 * 175 * Don't use this function from within an interrupt context. If you need 176 * an asynchronous message, or need to send a message from within interrupt 177 * context, use usb_submit_urb() If a thread in your driver uses this call, 178 * make sure your disconnect() method can wait for it to complete. Since you 179 * don't have a handle on the URB used, you can't cancel the request. 180 * 181 * Return: 182 * If successful, 0. Otherwise a negative error number. The number of actual 183 * bytes transferred will be stored in the @actual_length parameter. 184 */ 185 int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe, 186 void *data, int len, int *actual_length, int timeout) 187 { 188 return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout); 189 } 190 EXPORT_SYMBOL_GPL(usb_interrupt_msg); 191 192 /** 193 * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion 194 * @usb_dev: pointer to the usb device to send the message to 195 * @pipe: endpoint "pipe" to send the message to 196 * @data: pointer to the data to send 197 * @len: length in bytes of the data to send 198 * @actual_length: pointer to a location to put the actual length transferred 199 * in bytes 200 * @timeout: time in msecs to wait for the message to complete before 201 * timing out (if 0 the wait is forever) 202 * 203 * Context: !in_interrupt () 204 * 205 * This function sends a simple bulk message to a specified endpoint 206 * and waits for the message to complete, or timeout. 207 * 208 * Don't use this function from within an interrupt context. If you need 209 * an asynchronous message, or need to send a message from within interrupt 210 * context, use usb_submit_urb() If a thread in your driver uses this call, 211 * make sure your disconnect() method can wait for it to complete. Since you 212 * don't have a handle on the URB used, you can't cancel the request. 213 * 214 * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT ioctl, 215 * users are forced to abuse this routine by using it to submit URBs for 216 * interrupt endpoints. We will take the liberty of creating an interrupt URB 217 * (with the default interval) if the target is an interrupt endpoint. 218 * 219 * Return: 220 * If successful, 0. Otherwise a negative error number. The number of actual 221 * bytes transferred will be stored in the @actual_length parameter. 222 * 223 */ 224 int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, 225 void *data, int len, int *actual_length, int timeout) 226 { 227 struct urb *urb; 228 struct usb_host_endpoint *ep; 229 230 ep = usb_pipe_endpoint(usb_dev, pipe); 231 if (!ep || len < 0) 232 return -EINVAL; 233 234 urb = usb_alloc_urb(0, GFP_KERNEL); 235 if (!urb) 236 return -ENOMEM; 237 238 if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == 239 USB_ENDPOINT_XFER_INT) { 240 pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30); 241 usb_fill_int_urb(urb, usb_dev, pipe, data, len, 242 usb_api_blocking_completion, NULL, 243 ep->desc.bInterval); 244 } else 245 usb_fill_bulk_urb(urb, usb_dev, pipe, data, len, 246 usb_api_blocking_completion, NULL); 247 248 return usb_start_wait_urb(urb, timeout, actual_length); 249 } 250 EXPORT_SYMBOL_GPL(usb_bulk_msg); 251 252 /*-------------------------------------------------------------------*/ 253 254 static void sg_clean(struct usb_sg_request *io) 255 { 256 if (io->urbs) { 257 while (io->entries--) 258 usb_free_urb(io->urbs[io->entries]); 259 kfree(io->urbs); 260 io->urbs = NULL; 261 } 262 io->dev = NULL; 263 } 264 265 static void sg_complete(struct urb *urb) 266 { 267 struct usb_sg_request *io = urb->context; 268 int status = urb->status; 269 270 spin_lock(&io->lock); 271 272 /* In 2.5 we require hcds' endpoint queues not to progress after fault 273 * reports, until the completion callback (this!) returns. That lets 274 * device driver code (like this routine) unlink queued urbs first, 275 * if it needs to, since the HC won't work on them at all. So it's 276 * not possible for page N+1 to overwrite page N, and so on. 277 * 278 * That's only for "hard" faults; "soft" faults (unlinks) sometimes 279 * complete before the HCD can get requests away from hardware, 280 * though never during cleanup after a hard fault. 281 */ 282 if (io->status 283 && (io->status != -ECONNRESET 284 || status != -ECONNRESET) 285 && urb->actual_length) { 286 dev_err(io->dev->bus->controller, 287 "dev %s ep%d%s scatterlist error %d/%d\n", 288 io->dev->devpath, 289 usb_endpoint_num(&urb->ep->desc), 290 usb_urb_dir_in(urb) ? "in" : "out", 291 status, io->status); 292 /* BUG (); */ 293 } 294 295 if (io->status == 0 && status && status != -ECONNRESET) { 296 int i, found, retval; 297 298 io->status = status; 299 300 /* the previous urbs, and this one, completed already. 301 * unlink pending urbs so they won't rx/tx bad data. 302 * careful: unlink can sometimes be synchronous... 303 */ 304 spin_unlock(&io->lock); 305 for (i = 0, found = 0; i < io->entries; i++) { 306 if (!io->urbs[i]) 307 continue; 308 if (found) { 309 usb_block_urb(io->urbs[i]); 310 retval = usb_unlink_urb(io->urbs[i]); 311 if (retval != -EINPROGRESS && 312 retval != -ENODEV && 313 retval != -EBUSY && 314 retval != -EIDRM) 315 dev_err(&io->dev->dev, 316 "%s, unlink --> %d\n", 317 __func__, retval); 318 } else if (urb == io->urbs[i]) 319 found = 1; 320 } 321 spin_lock(&io->lock); 322 } 323 324 /* on the last completion, signal usb_sg_wait() */ 325 io->bytes += urb->actual_length; 326 io->count--; 327 if (!io->count) 328 complete(&io->complete); 329 330 spin_unlock(&io->lock); 331 } 332 333 334 /** 335 * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request 336 * @io: request block being initialized. until usb_sg_wait() returns, 337 * treat this as a pointer to an opaque block of memory, 338 * @dev: the usb device that will send or receive the data 339 * @pipe: endpoint "pipe" used to transfer the data 340 * @period: polling rate for interrupt endpoints, in frames or 341 * (for high speed endpoints) microframes; ignored for bulk 342 * @sg: scatterlist entries 343 * @nents: how many entries in the scatterlist 344 * @length: how many bytes to send from the scatterlist, or zero to 345 * send every byte identified in the list. 346 * @mem_flags: SLAB_* flags affecting memory allocations in this call 347 * 348 * This initializes a scatter/gather request, allocating resources such as 349 * I/O mappings and urb memory (except maybe memory used by USB controller 350 * drivers). 351 * 352 * The request must be issued using usb_sg_wait(), which waits for the I/O to 353 * complete (or to be canceled) and then cleans up all resources allocated by 354 * usb_sg_init(). 355 * 356 * The request may be canceled with usb_sg_cancel(), either before or after 357 * usb_sg_wait() is called. 358 * 359 * Return: Zero for success, else a negative errno value. 360 */ 361 int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev, 362 unsigned pipe, unsigned period, struct scatterlist *sg, 363 int nents, size_t length, gfp_t mem_flags) 364 { 365 int i; 366 int urb_flags; 367 int use_sg; 368 369 if (!io || !dev || !sg 370 || usb_pipecontrol(pipe) 371 || usb_pipeisoc(pipe) 372 || nents <= 0) 373 return -EINVAL; 374 375 spin_lock_init(&io->lock); 376 io->dev = dev; 377 io->pipe = pipe; 378 379 if (dev->bus->sg_tablesize > 0) { 380 use_sg = true; 381 io->entries = 1; 382 } else { 383 use_sg = false; 384 io->entries = nents; 385 } 386 387 /* initialize all the urbs we'll use */ 388 io->urbs = kmalloc(io->entries * sizeof(*io->urbs), mem_flags); 389 if (!io->urbs) 390 goto nomem; 391 392 urb_flags = URB_NO_INTERRUPT; 393 if (usb_pipein(pipe)) 394 urb_flags |= URB_SHORT_NOT_OK; 395 396 for_each_sg(sg, sg, io->entries, i) { 397 struct urb *urb; 398 unsigned len; 399 400 urb = usb_alloc_urb(0, mem_flags); 401 if (!urb) { 402 io->entries = i; 403 goto nomem; 404 } 405 io->urbs[i] = urb; 406 407 urb->dev = NULL; 408 urb->pipe = pipe; 409 urb->interval = period; 410 urb->transfer_flags = urb_flags; 411 urb->complete = sg_complete; 412 urb->context = io; 413 urb->sg = sg; 414 415 if (use_sg) { 416 /* There is no single transfer buffer */ 417 urb->transfer_buffer = NULL; 418 urb->num_sgs = nents; 419 420 /* A length of zero means transfer the whole sg list */ 421 len = length; 422 if (len == 0) { 423 struct scatterlist *sg2; 424 int j; 425 426 for_each_sg(sg, sg2, nents, j) 427 len += sg2->length; 428 } 429 } else { 430 /* 431 * Some systems can't use DMA; they use PIO instead. 432 * For their sakes, transfer_buffer is set whenever 433 * possible. 434 */ 435 if (!PageHighMem(sg_page(sg))) 436 urb->transfer_buffer = sg_virt(sg); 437 else 438 urb->transfer_buffer = NULL; 439 440 len = sg->length; 441 if (length) { 442 len = min_t(size_t, len, length); 443 length -= len; 444 if (length == 0) 445 io->entries = i + 1; 446 } 447 } 448 urb->transfer_buffer_length = len; 449 } 450 io->urbs[--i]->transfer_flags &= ~URB_NO_INTERRUPT; 451 452 /* transaction state */ 453 io->count = io->entries; 454 io->status = 0; 455 io->bytes = 0; 456 init_completion(&io->complete); 457 return 0; 458 459 nomem: 460 sg_clean(io); 461 return -ENOMEM; 462 } 463 EXPORT_SYMBOL_GPL(usb_sg_init); 464 465 /** 466 * usb_sg_wait - synchronously execute scatter/gather request 467 * @io: request block handle, as initialized with usb_sg_init(). 468 * some fields become accessible when this call returns. 469 * Context: !in_interrupt () 470 * 471 * This function blocks until the specified I/O operation completes. It 472 * leverages the grouping of the related I/O requests to get good transfer 473 * rates, by queueing the requests. At higher speeds, such queuing can 474 * significantly improve USB throughput. 475 * 476 * There are three kinds of completion for this function. 477 * 478 * (1) success, where io->status is zero. The number of io->bytes 479 * transferred is as requested. 480 * (2) error, where io->status is a negative errno value. The number 481 * of io->bytes transferred before the error is usually less 482 * than requested, and can be nonzero. 483 * (3) cancellation, a type of error with status -ECONNRESET that 484 * is initiated by usb_sg_cancel(). 485 * 486 * When this function returns, all memory allocated through usb_sg_init() or 487 * this call will have been freed. The request block parameter may still be 488 * passed to usb_sg_cancel(), or it may be freed. It could also be 489 * reinitialized and then reused. 490 * 491 * Data Transfer Rates: 492 * 493 * Bulk transfers are valid for full or high speed endpoints. 494 * The best full speed data rate is 19 packets of 64 bytes each 495 * per frame, or 1216 bytes per millisecond. 496 * The best high speed data rate is 13 packets of 512 bytes each 497 * per microframe, or 52 KBytes per millisecond. 498 * 499 * The reason to use interrupt transfers through this API would most likely 500 * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond 501 * could be transferred. That capability is less useful for low or full 502 * speed interrupt endpoints, which allow at most one packet per millisecond, 503 * of at most 8 or 64 bytes (respectively). 504 * 505 * It is not necessary to call this function to reserve bandwidth for devices 506 * under an xHCI host controller, as the bandwidth is reserved when the 507 * configuration or interface alt setting is selected. 508 */ 509 void usb_sg_wait(struct usb_sg_request *io) 510 { 511 int i; 512 int entries = io->entries; 513 514 /* queue the urbs. */ 515 spin_lock_irq(&io->lock); 516 i = 0; 517 while (i < entries && !io->status) { 518 int retval; 519 520 io->urbs[i]->dev = io->dev; 521 spin_unlock_irq(&io->lock); 522 523 retval = usb_submit_urb(io->urbs[i], GFP_NOIO); 524 525 switch (retval) { 526 /* maybe we retrying will recover */ 527 case -ENXIO: /* hc didn't queue this one */ 528 case -EAGAIN: 529 case -ENOMEM: 530 retval = 0; 531 yield(); 532 break; 533 534 /* no error? continue immediately. 535 * 536 * NOTE: to work better with UHCI (4K I/O buffer may 537 * need 3K of TDs) it may be good to limit how many 538 * URBs are queued at once; N milliseconds? 539 */ 540 case 0: 541 ++i; 542 cpu_relax(); 543 break; 544 545 /* fail any uncompleted urbs */ 546 default: 547 io->urbs[i]->status = retval; 548 dev_dbg(&io->dev->dev, "%s, submit --> %d\n", 549 __func__, retval); 550 usb_sg_cancel(io); 551 } 552 spin_lock_irq(&io->lock); 553 if (retval && (io->status == 0 || io->status == -ECONNRESET)) 554 io->status = retval; 555 } 556 io->count -= entries - i; 557 if (io->count == 0) 558 complete(&io->complete); 559 spin_unlock_irq(&io->lock); 560 561 /* OK, yes, this could be packaged as non-blocking. 562 * So could the submit loop above ... but it's easier to 563 * solve neither problem than to solve both! 564 */ 565 wait_for_completion(&io->complete); 566 567 sg_clean(io); 568 } 569 EXPORT_SYMBOL_GPL(usb_sg_wait); 570 571 /** 572 * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait() 573 * @io: request block, initialized with usb_sg_init() 574 * 575 * This stops a request after it has been started by usb_sg_wait(). 576 * It can also prevents one initialized by usb_sg_init() from starting, 577 * so that call just frees resources allocated to the request. 578 */ 579 void usb_sg_cancel(struct usb_sg_request *io) 580 { 581 unsigned long flags; 582 int i, retval; 583 584 spin_lock_irqsave(&io->lock, flags); 585 if (io->status) { 586 spin_unlock_irqrestore(&io->lock, flags); 587 return; 588 } 589 /* shut everything down */ 590 io->status = -ECONNRESET; 591 spin_unlock_irqrestore(&io->lock, flags); 592 593 for (i = io->entries - 1; i >= 0; --i) { 594 usb_block_urb(io->urbs[i]); 595 596 retval = usb_unlink_urb(io->urbs[i]); 597 if (retval != -EINPROGRESS 598 && retval != -ENODEV 599 && retval != -EBUSY 600 && retval != -EIDRM) 601 dev_warn(&io->dev->dev, "%s, unlink --> %d\n", 602 __func__, retval); 603 } 604 } 605 EXPORT_SYMBOL_GPL(usb_sg_cancel); 606 607 /*-------------------------------------------------------------------*/ 608 609 /** 610 * usb_get_descriptor - issues a generic GET_DESCRIPTOR request 611 * @dev: the device whose descriptor is being retrieved 612 * @type: the descriptor type (USB_DT_*) 613 * @index: the number of the descriptor 614 * @buf: where to put the descriptor 615 * @size: how big is "buf"? 616 * Context: !in_interrupt () 617 * 618 * Gets a USB descriptor. Convenience functions exist to simplify 619 * getting some types of descriptors. Use 620 * usb_get_string() or usb_string() for USB_DT_STRING. 621 * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG) 622 * are part of the device structure. 623 * In addition to a number of USB-standard descriptors, some 624 * devices also use class-specific or vendor-specific descriptors. 625 * 626 * This call is synchronous, and may not be used in an interrupt context. 627 * 628 * Return: The number of bytes received on success, or else the status code 629 * returned by the underlying usb_control_msg() call. 630 */ 631 int usb_get_descriptor(struct usb_device *dev, unsigned char type, 632 unsigned char index, void *buf, int size) 633 { 634 int i; 635 int result; 636 637 memset(buf, 0, size); /* Make sure we parse really received data */ 638 639 for (i = 0; i < 3; ++i) { 640 /* retry on length 0 or error; some devices are flakey */ 641 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 642 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, 643 (type << 8) + index, 0, buf, size, 644 USB_CTRL_GET_TIMEOUT); 645 if (result <= 0 && result != -ETIMEDOUT) 646 continue; 647 if (result > 1 && ((u8 *)buf)[1] != type) { 648 result = -ENODATA; 649 continue; 650 } 651 break; 652 } 653 return result; 654 } 655 EXPORT_SYMBOL_GPL(usb_get_descriptor); 656 657 /** 658 * usb_get_string - gets a string descriptor 659 * @dev: the device whose string descriptor is being retrieved 660 * @langid: code for language chosen (from string descriptor zero) 661 * @index: the number of the descriptor 662 * @buf: where to put the string 663 * @size: how big is "buf"? 664 * Context: !in_interrupt () 665 * 666 * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character, 667 * in little-endian byte order). 668 * The usb_string() function will often be a convenient way to turn 669 * these strings into kernel-printable form. 670 * 671 * Strings may be referenced in device, configuration, interface, or other 672 * descriptors, and could also be used in vendor-specific ways. 673 * 674 * This call is synchronous, and may not be used in an interrupt context. 675 * 676 * Return: The number of bytes received on success, or else the status code 677 * returned by the underlying usb_control_msg() call. 678 */ 679 static int usb_get_string(struct usb_device *dev, unsigned short langid, 680 unsigned char index, void *buf, int size) 681 { 682 int i; 683 int result; 684 685 for (i = 0; i < 3; ++i) { 686 /* retry on length 0 or stall; some devices are flakey */ 687 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 688 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, 689 (USB_DT_STRING << 8) + index, langid, buf, size, 690 USB_CTRL_GET_TIMEOUT); 691 if (result == 0 || result == -EPIPE) 692 continue; 693 if (result > 1 && ((u8 *) buf)[1] != USB_DT_STRING) { 694 result = -ENODATA; 695 continue; 696 } 697 break; 698 } 699 return result; 700 } 701 702 static void usb_try_string_workarounds(unsigned char *buf, int *length) 703 { 704 int newlength, oldlength = *length; 705 706 for (newlength = 2; newlength + 1 < oldlength; newlength += 2) 707 if (!isprint(buf[newlength]) || buf[newlength + 1]) 708 break; 709 710 if (newlength > 2) { 711 buf[0] = newlength; 712 *length = newlength; 713 } 714 } 715 716 static int usb_string_sub(struct usb_device *dev, unsigned int langid, 717 unsigned int index, unsigned char *buf) 718 { 719 int rc; 720 721 /* Try to read the string descriptor by asking for the maximum 722 * possible number of bytes */ 723 if (dev->quirks & USB_QUIRK_STRING_FETCH_255) 724 rc = -EIO; 725 else 726 rc = usb_get_string(dev, langid, index, buf, 255); 727 728 /* If that failed try to read the descriptor length, then 729 * ask for just that many bytes */ 730 if (rc < 2) { 731 rc = usb_get_string(dev, langid, index, buf, 2); 732 if (rc == 2) 733 rc = usb_get_string(dev, langid, index, buf, buf[0]); 734 } 735 736 if (rc >= 2) { 737 if (!buf[0] && !buf[1]) 738 usb_try_string_workarounds(buf, &rc); 739 740 /* There might be extra junk at the end of the descriptor */ 741 if (buf[0] < rc) 742 rc = buf[0]; 743 744 rc = rc - (rc & 1); /* force a multiple of two */ 745 } 746 747 if (rc < 2) 748 rc = (rc < 0 ? rc : -EINVAL); 749 750 return rc; 751 } 752 753 static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf) 754 { 755 int err; 756 757 if (dev->have_langid) 758 return 0; 759 760 if (dev->string_langid < 0) 761 return -EPIPE; 762 763 err = usb_string_sub(dev, 0, 0, tbuf); 764 765 /* If the string was reported but is malformed, default to english 766 * (0x0409) */ 767 if (err == -ENODATA || (err > 0 && err < 4)) { 768 dev->string_langid = 0x0409; 769 dev->have_langid = 1; 770 dev_err(&dev->dev, 771 "language id specifier not provided by device, defaulting to English\n"); 772 return 0; 773 } 774 775 /* In case of all other errors, we assume the device is not able to 776 * deal with strings at all. Set string_langid to -1 in order to 777 * prevent any string to be retrieved from the device */ 778 if (err < 0) { 779 dev_err(&dev->dev, "string descriptor 0 read error: %d\n", 780 err); 781 dev->string_langid = -1; 782 return -EPIPE; 783 } 784 785 /* always use the first langid listed */ 786 dev->string_langid = tbuf[2] | (tbuf[3] << 8); 787 dev->have_langid = 1; 788 dev_dbg(&dev->dev, "default language 0x%04x\n", 789 dev->string_langid); 790 return 0; 791 } 792 793 /** 794 * usb_string - returns UTF-8 version of a string descriptor 795 * @dev: the device whose string descriptor is being retrieved 796 * @index: the number of the descriptor 797 * @buf: where to put the string 798 * @size: how big is "buf"? 799 * Context: !in_interrupt () 800 * 801 * This converts the UTF-16LE encoded strings returned by devices, from 802 * usb_get_string_descriptor(), to null-terminated UTF-8 encoded ones 803 * that are more usable in most kernel contexts. Note that this function 804 * chooses strings in the first language supported by the device. 805 * 806 * This call is synchronous, and may not be used in an interrupt context. 807 * 808 * Return: length of the string (>= 0) or usb_control_msg status (< 0). 809 */ 810 int usb_string(struct usb_device *dev, int index, char *buf, size_t size) 811 { 812 unsigned char *tbuf; 813 int err; 814 815 if (dev->state == USB_STATE_SUSPENDED) 816 return -EHOSTUNREACH; 817 if (size <= 0 || !buf || !index) 818 return -EINVAL; 819 buf[0] = 0; 820 tbuf = kmalloc(256, GFP_NOIO); 821 if (!tbuf) 822 return -ENOMEM; 823 824 err = usb_get_langid(dev, tbuf); 825 if (err < 0) 826 goto errout; 827 828 err = usb_string_sub(dev, dev->string_langid, index, tbuf); 829 if (err < 0) 830 goto errout; 831 832 size--; /* leave room for trailing NULL char in output buffer */ 833 err = utf16s_to_utf8s((wchar_t *) &tbuf[2], (err - 2) / 2, 834 UTF16_LITTLE_ENDIAN, buf, size); 835 buf[err] = 0; 836 837 if (tbuf[1] != USB_DT_STRING) 838 dev_dbg(&dev->dev, 839 "wrong descriptor type %02x for string %d (\"%s\")\n", 840 tbuf[1], index, buf); 841 842 errout: 843 kfree(tbuf); 844 return err; 845 } 846 EXPORT_SYMBOL_GPL(usb_string); 847 848 /* one UTF-8-encoded 16-bit character has at most three bytes */ 849 #define MAX_USB_STRING_SIZE (127 * 3 + 1) 850 851 /** 852 * usb_cache_string - read a string descriptor and cache it for later use 853 * @udev: the device whose string descriptor is being read 854 * @index: the descriptor index 855 * 856 * Return: A pointer to a kmalloc'ed buffer containing the descriptor string, 857 * or %NULL if the index is 0 or the string could not be read. 858 */ 859 char *usb_cache_string(struct usb_device *udev, int index) 860 { 861 char *buf; 862 char *smallbuf = NULL; 863 int len; 864 865 if (index <= 0) 866 return NULL; 867 868 buf = kmalloc(MAX_USB_STRING_SIZE, GFP_NOIO); 869 if (buf) { 870 len = usb_string(udev, index, buf, MAX_USB_STRING_SIZE); 871 if (len > 0) { 872 smallbuf = kmalloc(++len, GFP_NOIO); 873 if (!smallbuf) 874 return buf; 875 memcpy(smallbuf, buf, len); 876 } 877 kfree(buf); 878 } 879 return smallbuf; 880 } 881 882 /* 883 * usb_get_device_descriptor - (re)reads the device descriptor (usbcore) 884 * @dev: the device whose device descriptor is being updated 885 * @size: how much of the descriptor to read 886 * Context: !in_interrupt () 887 * 888 * Updates the copy of the device descriptor stored in the device structure, 889 * which dedicates space for this purpose. 890 * 891 * Not exported, only for use by the core. If drivers really want to read 892 * the device descriptor directly, they can call usb_get_descriptor() with 893 * type = USB_DT_DEVICE and index = 0. 894 * 895 * This call is synchronous, and may not be used in an interrupt context. 896 * 897 * Return: The number of bytes received on success, or else the status code 898 * returned by the underlying usb_control_msg() call. 899 */ 900 int usb_get_device_descriptor(struct usb_device *dev, unsigned int size) 901 { 902 struct usb_device_descriptor *desc; 903 int ret; 904 905 if (size > sizeof(*desc)) 906 return -EINVAL; 907 desc = kmalloc(sizeof(*desc), GFP_NOIO); 908 if (!desc) 909 return -ENOMEM; 910 911 ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size); 912 if (ret >= 0) 913 memcpy(&dev->descriptor, desc, size); 914 kfree(desc); 915 return ret; 916 } 917 918 /** 919 * usb_get_status - issues a GET_STATUS call 920 * @dev: the device whose status is being checked 921 * @recip: USB_RECIP_*; for device, interface, or endpoint 922 * @type: USB_STATUS_TYPE_*; for standard or PTM status types 923 * @target: zero (for device), else interface or endpoint number 924 * @data: pointer to two bytes of bitmap data 925 * Context: !in_interrupt () 926 * 927 * Returns device, interface, or endpoint status. Normally only of 928 * interest to see if the device is self powered, or has enabled the 929 * remote wakeup facility; or whether a bulk or interrupt endpoint 930 * is halted ("stalled"). 931 * 932 * Bits in these status bitmaps are set using the SET_FEATURE request, 933 * and cleared using the CLEAR_FEATURE request. The usb_clear_halt() 934 * function should be used to clear halt ("stall") status. 935 * 936 * This call is synchronous, and may not be used in an interrupt context. 937 * 938 * Returns 0 and the status value in *@data (in host byte order) on success, 939 * or else the status code from the underlying usb_control_msg() call. 940 */ 941 int usb_get_status(struct usb_device *dev, int recip, int type, int target, 942 void *data) 943 { 944 int ret; 945 void *status; 946 int length; 947 948 switch (type) { 949 case USB_STATUS_TYPE_STANDARD: 950 length = 2; 951 break; 952 case USB_STATUS_TYPE_PTM: 953 if (recip != USB_RECIP_DEVICE) 954 return -EINVAL; 955 956 length = 4; 957 break; 958 default: 959 return -EINVAL; 960 } 961 962 status = kmalloc(length, GFP_KERNEL); 963 if (!status) 964 return -ENOMEM; 965 966 ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 967 USB_REQ_GET_STATUS, USB_DIR_IN | recip, USB_STATUS_TYPE_STANDARD, 968 target, status, length, USB_CTRL_GET_TIMEOUT); 969 970 switch (ret) { 971 case 4: 972 if (type != USB_STATUS_TYPE_PTM) { 973 ret = -EIO; 974 break; 975 } 976 977 *(u32 *) data = le32_to_cpu(*(__le32 *) status); 978 ret = 0; 979 break; 980 case 2: 981 if (type != USB_STATUS_TYPE_STANDARD) { 982 ret = -EIO; 983 break; 984 } 985 986 *(u16 *) data = le16_to_cpu(*(__le16 *) status); 987 ret = 0; 988 break; 989 default: 990 ret = -EIO; 991 } 992 993 kfree(status); 994 return ret; 995 } 996 EXPORT_SYMBOL_GPL(usb_get_status); 997 998 /** 999 * usb_clear_halt - tells device to clear endpoint halt/stall condition 1000 * @dev: device whose endpoint is halted 1001 * @pipe: endpoint "pipe" being cleared 1002 * Context: !in_interrupt () 1003 * 1004 * This is used to clear halt conditions for bulk and interrupt endpoints, 1005 * as reported by URB completion status. Endpoints that are halted are 1006 * sometimes referred to as being "stalled". Such endpoints are unable 1007 * to transmit or receive data until the halt status is cleared. Any URBs 1008 * queued for such an endpoint should normally be unlinked by the driver 1009 * before clearing the halt condition, as described in sections 5.7.5 1010 * and 5.8.5 of the USB 2.0 spec. 1011 * 1012 * Note that control and isochronous endpoints don't halt, although control 1013 * endpoints report "protocol stall" (for unsupported requests) using the 1014 * same status code used to report a true stall. 1015 * 1016 * This call is synchronous, and may not be used in an interrupt context. 1017 * 1018 * Return: Zero on success, or else the status code returned by the 1019 * underlying usb_control_msg() call. 1020 */ 1021 int usb_clear_halt(struct usb_device *dev, int pipe) 1022 { 1023 int result; 1024 int endp = usb_pipeendpoint(pipe); 1025 1026 if (usb_pipein(pipe)) 1027 endp |= USB_DIR_IN; 1028 1029 /* we don't care if it wasn't halted first. in fact some devices 1030 * (like some ibmcam model 1 units) seem to expect hosts to make 1031 * this request for iso endpoints, which can't halt! 1032 */ 1033 result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1034 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 1035 USB_ENDPOINT_HALT, endp, NULL, 0, 1036 USB_CTRL_SET_TIMEOUT); 1037 1038 /* don't un-halt or force to DATA0 except on success */ 1039 if (result < 0) 1040 return result; 1041 1042 /* NOTE: seems like Microsoft and Apple don't bother verifying 1043 * the clear "took", so some devices could lock up if you check... 1044 * such as the Hagiwara FlashGate DUAL. So we won't bother. 1045 * 1046 * NOTE: make sure the logic here doesn't diverge much from 1047 * the copy in usb-storage, for as long as we need two copies. 1048 */ 1049 1050 usb_reset_endpoint(dev, endp); 1051 1052 return 0; 1053 } 1054 EXPORT_SYMBOL_GPL(usb_clear_halt); 1055 1056 static int create_intf_ep_devs(struct usb_interface *intf) 1057 { 1058 struct usb_device *udev = interface_to_usbdev(intf); 1059 struct usb_host_interface *alt = intf->cur_altsetting; 1060 int i; 1061 1062 if (intf->ep_devs_created || intf->unregistering) 1063 return 0; 1064 1065 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1066 (void) usb_create_ep_devs(&intf->dev, &alt->endpoint[i], udev); 1067 intf->ep_devs_created = 1; 1068 return 0; 1069 } 1070 1071 static void remove_intf_ep_devs(struct usb_interface *intf) 1072 { 1073 struct usb_host_interface *alt = intf->cur_altsetting; 1074 int i; 1075 1076 if (!intf->ep_devs_created) 1077 return; 1078 1079 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1080 usb_remove_ep_devs(&alt->endpoint[i]); 1081 intf->ep_devs_created = 0; 1082 } 1083 1084 /** 1085 * usb_disable_endpoint -- Disable an endpoint by address 1086 * @dev: the device whose endpoint is being disabled 1087 * @epaddr: the endpoint's address. Endpoint number for output, 1088 * endpoint number + USB_DIR_IN for input 1089 * @reset_hardware: flag to erase any endpoint state stored in the 1090 * controller hardware 1091 * 1092 * Disables the endpoint for URB submission and nukes all pending URBs. 1093 * If @reset_hardware is set then also deallocates hcd/hardware state 1094 * for the endpoint. 1095 */ 1096 void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr, 1097 bool reset_hardware) 1098 { 1099 unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; 1100 struct usb_host_endpoint *ep; 1101 1102 if (!dev) 1103 return; 1104 1105 if (usb_endpoint_out(epaddr)) { 1106 ep = dev->ep_out[epnum]; 1107 if (reset_hardware) 1108 dev->ep_out[epnum] = NULL; 1109 } else { 1110 ep = dev->ep_in[epnum]; 1111 if (reset_hardware) 1112 dev->ep_in[epnum] = NULL; 1113 } 1114 if (ep) { 1115 ep->enabled = 0; 1116 usb_hcd_flush_endpoint(dev, ep); 1117 if (reset_hardware) 1118 usb_hcd_disable_endpoint(dev, ep); 1119 } 1120 } 1121 1122 /** 1123 * usb_reset_endpoint - Reset an endpoint's state. 1124 * @dev: the device whose endpoint is to be reset 1125 * @epaddr: the endpoint's address. Endpoint number for output, 1126 * endpoint number + USB_DIR_IN for input 1127 * 1128 * Resets any host-side endpoint state such as the toggle bit, 1129 * sequence number or current window. 1130 */ 1131 void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr) 1132 { 1133 unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; 1134 struct usb_host_endpoint *ep; 1135 1136 if (usb_endpoint_out(epaddr)) 1137 ep = dev->ep_out[epnum]; 1138 else 1139 ep = dev->ep_in[epnum]; 1140 if (ep) 1141 usb_hcd_reset_endpoint(dev, ep); 1142 } 1143 EXPORT_SYMBOL_GPL(usb_reset_endpoint); 1144 1145 1146 /** 1147 * usb_disable_interface -- Disable all endpoints for an interface 1148 * @dev: the device whose interface is being disabled 1149 * @intf: pointer to the interface descriptor 1150 * @reset_hardware: flag to erase any endpoint state stored in the 1151 * controller hardware 1152 * 1153 * Disables all the endpoints for the interface's current altsetting. 1154 */ 1155 void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf, 1156 bool reset_hardware) 1157 { 1158 struct usb_host_interface *alt = intf->cur_altsetting; 1159 int i; 1160 1161 for (i = 0; i < alt->desc.bNumEndpoints; ++i) { 1162 usb_disable_endpoint(dev, 1163 alt->endpoint[i].desc.bEndpointAddress, 1164 reset_hardware); 1165 } 1166 } 1167 1168 /** 1169 * usb_disable_device - Disable all the endpoints for a USB device 1170 * @dev: the device whose endpoints are being disabled 1171 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. 1172 * 1173 * Disables all the device's endpoints, potentially including endpoint 0. 1174 * Deallocates hcd/hardware state for the endpoints (nuking all or most 1175 * pending urbs) and usbcore state for the interfaces, so that usbcore 1176 * must usb_set_configuration() before any interfaces could be used. 1177 */ 1178 void usb_disable_device(struct usb_device *dev, int skip_ep0) 1179 { 1180 int i; 1181 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1182 1183 /* getting rid of interfaces will disconnect 1184 * any drivers bound to them (a key side effect) 1185 */ 1186 if (dev->actconfig) { 1187 /* 1188 * FIXME: In order to avoid self-deadlock involving the 1189 * bandwidth_mutex, we have to mark all the interfaces 1190 * before unregistering any of them. 1191 */ 1192 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) 1193 dev->actconfig->interface[i]->unregistering = 1; 1194 1195 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1196 struct usb_interface *interface; 1197 1198 /* remove this interface if it has been registered */ 1199 interface = dev->actconfig->interface[i]; 1200 if (!device_is_registered(&interface->dev)) 1201 continue; 1202 dev_dbg(&dev->dev, "unregistering interface %s\n", 1203 dev_name(&interface->dev)); 1204 remove_intf_ep_devs(interface); 1205 device_del(&interface->dev); 1206 } 1207 1208 /* Now that the interfaces are unbound, nobody should 1209 * try to access them. 1210 */ 1211 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1212 put_device(&dev->actconfig->interface[i]->dev); 1213 dev->actconfig->interface[i] = NULL; 1214 } 1215 1216 if (dev->usb2_hw_lpm_enabled == 1) 1217 usb_set_usb2_hardware_lpm(dev, 0); 1218 usb_unlocked_disable_lpm(dev); 1219 usb_disable_ltm(dev); 1220 1221 dev->actconfig = NULL; 1222 if (dev->state == USB_STATE_CONFIGURED) 1223 usb_set_device_state(dev, USB_STATE_ADDRESS); 1224 } 1225 1226 dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__, 1227 skip_ep0 ? "non-ep0" : "all"); 1228 if (hcd->driver->check_bandwidth) { 1229 /* First pass: Cancel URBs, leave endpoint pointers intact. */ 1230 for (i = skip_ep0; i < 16; ++i) { 1231 usb_disable_endpoint(dev, i, false); 1232 usb_disable_endpoint(dev, i + USB_DIR_IN, false); 1233 } 1234 /* Remove endpoints from the host controller internal state */ 1235 mutex_lock(hcd->bandwidth_mutex); 1236 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1237 mutex_unlock(hcd->bandwidth_mutex); 1238 /* Second pass: remove endpoint pointers */ 1239 } 1240 for (i = skip_ep0; i < 16; ++i) { 1241 usb_disable_endpoint(dev, i, true); 1242 usb_disable_endpoint(dev, i + USB_DIR_IN, true); 1243 } 1244 } 1245 1246 /** 1247 * usb_enable_endpoint - Enable an endpoint for USB communications 1248 * @dev: the device whose interface is being enabled 1249 * @ep: the endpoint 1250 * @reset_ep: flag to reset the endpoint state 1251 * 1252 * Resets the endpoint state if asked, and sets dev->ep_{in,out} pointers. 1253 * For control endpoints, both the input and output sides are handled. 1254 */ 1255 void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep, 1256 bool reset_ep) 1257 { 1258 int epnum = usb_endpoint_num(&ep->desc); 1259 int is_out = usb_endpoint_dir_out(&ep->desc); 1260 int is_control = usb_endpoint_xfer_control(&ep->desc); 1261 1262 if (reset_ep) 1263 usb_hcd_reset_endpoint(dev, ep); 1264 if (is_out || is_control) 1265 dev->ep_out[epnum] = ep; 1266 if (!is_out || is_control) 1267 dev->ep_in[epnum] = ep; 1268 ep->enabled = 1; 1269 } 1270 1271 /** 1272 * usb_enable_interface - Enable all the endpoints for an interface 1273 * @dev: the device whose interface is being enabled 1274 * @intf: pointer to the interface descriptor 1275 * @reset_eps: flag to reset the endpoints' state 1276 * 1277 * Enables all the endpoints for the interface's current altsetting. 1278 */ 1279 void usb_enable_interface(struct usb_device *dev, 1280 struct usb_interface *intf, bool reset_eps) 1281 { 1282 struct usb_host_interface *alt = intf->cur_altsetting; 1283 int i; 1284 1285 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1286 usb_enable_endpoint(dev, &alt->endpoint[i], reset_eps); 1287 } 1288 1289 /** 1290 * usb_set_interface - Makes a particular alternate setting be current 1291 * @dev: the device whose interface is being updated 1292 * @interface: the interface being updated 1293 * @alternate: the setting being chosen. 1294 * Context: !in_interrupt () 1295 * 1296 * This is used to enable data transfers on interfaces that may not 1297 * be enabled by default. Not all devices support such configurability. 1298 * Only the driver bound to an interface may change its setting. 1299 * 1300 * Within any given configuration, each interface may have several 1301 * alternative settings. These are often used to control levels of 1302 * bandwidth consumption. For example, the default setting for a high 1303 * speed interrupt endpoint may not send more than 64 bytes per microframe, 1304 * while interrupt transfers of up to 3KBytes per microframe are legal. 1305 * Also, isochronous endpoints may never be part of an 1306 * interface's default setting. To access such bandwidth, alternate 1307 * interface settings must be made current. 1308 * 1309 * Note that in the Linux USB subsystem, bandwidth associated with 1310 * an endpoint in a given alternate setting is not reserved until an URB 1311 * is submitted that needs that bandwidth. Some other operating systems 1312 * allocate bandwidth early, when a configuration is chosen. 1313 * 1314 * This call is synchronous, and may not be used in an interrupt context. 1315 * Also, drivers must not change altsettings while urbs are scheduled for 1316 * endpoints in that interface; all such urbs must first be completed 1317 * (perhaps forced by unlinking). 1318 * 1319 * Return: Zero on success, or else the status code returned by the 1320 * underlying usb_control_msg() call. 1321 */ 1322 int usb_set_interface(struct usb_device *dev, int interface, int alternate) 1323 { 1324 struct usb_interface *iface; 1325 struct usb_host_interface *alt; 1326 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1327 int i, ret, manual = 0; 1328 unsigned int epaddr; 1329 unsigned int pipe; 1330 1331 if (dev->state == USB_STATE_SUSPENDED) 1332 return -EHOSTUNREACH; 1333 1334 iface = usb_ifnum_to_if(dev, interface); 1335 if (!iface) { 1336 dev_dbg(&dev->dev, "selecting invalid interface %d\n", 1337 interface); 1338 return -EINVAL; 1339 } 1340 if (iface->unregistering) 1341 return -ENODEV; 1342 1343 alt = usb_altnum_to_altsetting(iface, alternate); 1344 if (!alt) { 1345 dev_warn(&dev->dev, "selecting invalid altsetting %d\n", 1346 alternate); 1347 return -EINVAL; 1348 } 1349 1350 /* Make sure we have enough bandwidth for this alternate interface. 1351 * Remove the current alt setting and add the new alt setting. 1352 */ 1353 mutex_lock(hcd->bandwidth_mutex); 1354 /* Disable LPM, and re-enable it once the new alt setting is installed, 1355 * so that the xHCI driver can recalculate the U1/U2 timeouts. 1356 */ 1357 if (usb_disable_lpm(dev)) { 1358 dev_err(&iface->dev, "%s Failed to disable LPM\n.", __func__); 1359 mutex_unlock(hcd->bandwidth_mutex); 1360 return -ENOMEM; 1361 } 1362 /* Changing alt-setting also frees any allocated streams */ 1363 for (i = 0; i < iface->cur_altsetting->desc.bNumEndpoints; i++) 1364 iface->cur_altsetting->endpoint[i].streams = 0; 1365 1366 ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt); 1367 if (ret < 0) { 1368 dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n", 1369 alternate); 1370 usb_enable_lpm(dev); 1371 mutex_unlock(hcd->bandwidth_mutex); 1372 return ret; 1373 } 1374 1375 if (dev->quirks & USB_QUIRK_NO_SET_INTF) 1376 ret = -EPIPE; 1377 else 1378 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1379 USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE, 1380 alternate, interface, NULL, 0, 5000); 1381 1382 /* 9.4.10 says devices don't need this and are free to STALL the 1383 * request if the interface only has one alternate setting. 1384 */ 1385 if (ret == -EPIPE && iface->num_altsetting == 1) { 1386 dev_dbg(&dev->dev, 1387 "manual set_interface for iface %d, alt %d\n", 1388 interface, alternate); 1389 manual = 1; 1390 } else if (ret < 0) { 1391 /* Re-instate the old alt setting */ 1392 usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting); 1393 usb_enable_lpm(dev); 1394 mutex_unlock(hcd->bandwidth_mutex); 1395 return ret; 1396 } 1397 mutex_unlock(hcd->bandwidth_mutex); 1398 1399 /* FIXME drivers shouldn't need to replicate/bugfix the logic here 1400 * when they implement async or easily-killable versions of this or 1401 * other "should-be-internal" functions (like clear_halt). 1402 * should hcd+usbcore postprocess control requests? 1403 */ 1404 1405 /* prevent submissions using previous endpoint settings */ 1406 if (iface->cur_altsetting != alt) { 1407 remove_intf_ep_devs(iface); 1408 usb_remove_sysfs_intf_files(iface); 1409 } 1410 usb_disable_interface(dev, iface, true); 1411 1412 iface->cur_altsetting = alt; 1413 1414 /* Now that the interface is installed, re-enable LPM. */ 1415 usb_unlocked_enable_lpm(dev); 1416 1417 /* If the interface only has one altsetting and the device didn't 1418 * accept the request, we attempt to carry out the equivalent action 1419 * by manually clearing the HALT feature for each endpoint in the 1420 * new altsetting. 1421 */ 1422 if (manual) { 1423 for (i = 0; i < alt->desc.bNumEndpoints; i++) { 1424 epaddr = alt->endpoint[i].desc.bEndpointAddress; 1425 pipe = __create_pipe(dev, 1426 USB_ENDPOINT_NUMBER_MASK & epaddr) | 1427 (usb_endpoint_out(epaddr) ? 1428 USB_DIR_OUT : USB_DIR_IN); 1429 1430 usb_clear_halt(dev, pipe); 1431 } 1432 } 1433 1434 /* 9.1.1.5: reset toggles for all endpoints in the new altsetting 1435 * 1436 * Note: 1437 * Despite EP0 is always present in all interfaces/AS, the list of 1438 * endpoints from the descriptor does not contain EP0. Due to its 1439 * omnipresence one might expect EP0 being considered "affected" by 1440 * any SetInterface request and hence assume toggles need to be reset. 1441 * However, EP0 toggles are re-synced for every individual transfer 1442 * during the SETUP stage - hence EP0 toggles are "don't care" here. 1443 * (Likewise, EP0 never "halts" on well designed devices.) 1444 */ 1445 usb_enable_interface(dev, iface, true); 1446 if (device_is_registered(&iface->dev)) { 1447 usb_create_sysfs_intf_files(iface); 1448 create_intf_ep_devs(iface); 1449 } 1450 return 0; 1451 } 1452 EXPORT_SYMBOL_GPL(usb_set_interface); 1453 1454 /** 1455 * usb_reset_configuration - lightweight device reset 1456 * @dev: the device whose configuration is being reset 1457 * 1458 * This issues a standard SET_CONFIGURATION request to the device using 1459 * the current configuration. The effect is to reset most USB-related 1460 * state in the device, including interface altsettings (reset to zero), 1461 * endpoint halts (cleared), and endpoint state (only for bulk and interrupt 1462 * endpoints). Other usbcore state is unchanged, including bindings of 1463 * usb device drivers to interfaces. 1464 * 1465 * Because this affects multiple interfaces, avoid using this with composite 1466 * (multi-interface) devices. Instead, the driver for each interface may 1467 * use usb_set_interface() on the interfaces it claims. Be careful though; 1468 * some devices don't support the SET_INTERFACE request, and others won't 1469 * reset all the interface state (notably endpoint state). Resetting the whole 1470 * configuration would affect other drivers' interfaces. 1471 * 1472 * The caller must own the device lock. 1473 * 1474 * Return: Zero on success, else a negative error code. 1475 */ 1476 int usb_reset_configuration(struct usb_device *dev) 1477 { 1478 int i, retval; 1479 struct usb_host_config *config; 1480 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1481 1482 if (dev->state == USB_STATE_SUSPENDED) 1483 return -EHOSTUNREACH; 1484 1485 /* caller must have locked the device and must own 1486 * the usb bus readlock (so driver bindings are stable); 1487 * calls during probe() are fine 1488 */ 1489 1490 for (i = 1; i < 16; ++i) { 1491 usb_disable_endpoint(dev, i, true); 1492 usb_disable_endpoint(dev, i + USB_DIR_IN, true); 1493 } 1494 1495 config = dev->actconfig; 1496 retval = 0; 1497 mutex_lock(hcd->bandwidth_mutex); 1498 /* Disable LPM, and re-enable it once the configuration is reset, so 1499 * that the xHCI driver can recalculate the U1/U2 timeouts. 1500 */ 1501 if (usb_disable_lpm(dev)) { 1502 dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__); 1503 mutex_unlock(hcd->bandwidth_mutex); 1504 return -ENOMEM; 1505 } 1506 /* Make sure we have enough bandwidth for each alternate setting 0 */ 1507 for (i = 0; i < config->desc.bNumInterfaces; i++) { 1508 struct usb_interface *intf = config->interface[i]; 1509 struct usb_host_interface *alt; 1510 1511 alt = usb_altnum_to_altsetting(intf, 0); 1512 if (!alt) 1513 alt = &intf->altsetting[0]; 1514 if (alt != intf->cur_altsetting) 1515 retval = usb_hcd_alloc_bandwidth(dev, NULL, 1516 intf->cur_altsetting, alt); 1517 if (retval < 0) 1518 break; 1519 } 1520 /* If not, reinstate the old alternate settings */ 1521 if (retval < 0) { 1522 reset_old_alts: 1523 for (i--; i >= 0; i--) { 1524 struct usb_interface *intf = config->interface[i]; 1525 struct usb_host_interface *alt; 1526 1527 alt = usb_altnum_to_altsetting(intf, 0); 1528 if (!alt) 1529 alt = &intf->altsetting[0]; 1530 if (alt != intf->cur_altsetting) 1531 usb_hcd_alloc_bandwidth(dev, NULL, 1532 alt, intf->cur_altsetting); 1533 } 1534 usb_enable_lpm(dev); 1535 mutex_unlock(hcd->bandwidth_mutex); 1536 return retval; 1537 } 1538 retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1539 USB_REQ_SET_CONFIGURATION, 0, 1540 config->desc.bConfigurationValue, 0, 1541 NULL, 0, USB_CTRL_SET_TIMEOUT); 1542 if (retval < 0) 1543 goto reset_old_alts; 1544 mutex_unlock(hcd->bandwidth_mutex); 1545 1546 /* re-init hc/hcd interface/endpoint state */ 1547 for (i = 0; i < config->desc.bNumInterfaces; i++) { 1548 struct usb_interface *intf = config->interface[i]; 1549 struct usb_host_interface *alt; 1550 1551 alt = usb_altnum_to_altsetting(intf, 0); 1552 1553 /* No altsetting 0? We'll assume the first altsetting. 1554 * We could use a GetInterface call, but if a device is 1555 * so non-compliant that it doesn't have altsetting 0 1556 * then I wouldn't trust its reply anyway. 1557 */ 1558 if (!alt) 1559 alt = &intf->altsetting[0]; 1560 1561 if (alt != intf->cur_altsetting) { 1562 remove_intf_ep_devs(intf); 1563 usb_remove_sysfs_intf_files(intf); 1564 } 1565 intf->cur_altsetting = alt; 1566 usb_enable_interface(dev, intf, true); 1567 if (device_is_registered(&intf->dev)) { 1568 usb_create_sysfs_intf_files(intf); 1569 create_intf_ep_devs(intf); 1570 } 1571 } 1572 /* Now that the interfaces are installed, re-enable LPM. */ 1573 usb_unlocked_enable_lpm(dev); 1574 return 0; 1575 } 1576 EXPORT_SYMBOL_GPL(usb_reset_configuration); 1577 1578 static void usb_release_interface(struct device *dev) 1579 { 1580 struct usb_interface *intf = to_usb_interface(dev); 1581 struct usb_interface_cache *intfc = 1582 altsetting_to_usb_interface_cache(intf->altsetting); 1583 1584 kref_put(&intfc->ref, usb_release_interface_cache); 1585 usb_put_dev(interface_to_usbdev(intf)); 1586 kfree(intf); 1587 } 1588 1589 /* 1590 * usb_deauthorize_interface - deauthorize an USB interface 1591 * 1592 * @intf: USB interface structure 1593 */ 1594 void usb_deauthorize_interface(struct usb_interface *intf) 1595 { 1596 struct device *dev = &intf->dev; 1597 1598 device_lock(dev->parent); 1599 1600 if (intf->authorized) { 1601 device_lock(dev); 1602 intf->authorized = 0; 1603 device_unlock(dev); 1604 1605 usb_forced_unbind_intf(intf); 1606 } 1607 1608 device_unlock(dev->parent); 1609 } 1610 1611 /* 1612 * usb_authorize_interface - authorize an USB interface 1613 * 1614 * @intf: USB interface structure 1615 */ 1616 void usb_authorize_interface(struct usb_interface *intf) 1617 { 1618 struct device *dev = &intf->dev; 1619 1620 if (!intf->authorized) { 1621 device_lock(dev); 1622 intf->authorized = 1; /* authorize interface */ 1623 device_unlock(dev); 1624 } 1625 } 1626 1627 static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env) 1628 { 1629 struct usb_device *usb_dev; 1630 struct usb_interface *intf; 1631 struct usb_host_interface *alt; 1632 1633 intf = to_usb_interface(dev); 1634 usb_dev = interface_to_usbdev(intf); 1635 alt = intf->cur_altsetting; 1636 1637 if (add_uevent_var(env, "INTERFACE=%d/%d/%d", 1638 alt->desc.bInterfaceClass, 1639 alt->desc.bInterfaceSubClass, 1640 alt->desc.bInterfaceProtocol)) 1641 return -ENOMEM; 1642 1643 if (add_uevent_var(env, 1644 "MODALIAS=usb:" 1645 "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02Xin%02X", 1646 le16_to_cpu(usb_dev->descriptor.idVendor), 1647 le16_to_cpu(usb_dev->descriptor.idProduct), 1648 le16_to_cpu(usb_dev->descriptor.bcdDevice), 1649 usb_dev->descriptor.bDeviceClass, 1650 usb_dev->descriptor.bDeviceSubClass, 1651 usb_dev->descriptor.bDeviceProtocol, 1652 alt->desc.bInterfaceClass, 1653 alt->desc.bInterfaceSubClass, 1654 alt->desc.bInterfaceProtocol, 1655 alt->desc.bInterfaceNumber)) 1656 return -ENOMEM; 1657 1658 return 0; 1659 } 1660 1661 struct device_type usb_if_device_type = { 1662 .name = "usb_interface", 1663 .release = usb_release_interface, 1664 .uevent = usb_if_uevent, 1665 }; 1666 1667 static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev, 1668 struct usb_host_config *config, 1669 u8 inum) 1670 { 1671 struct usb_interface_assoc_descriptor *retval = NULL; 1672 struct usb_interface_assoc_descriptor *intf_assoc; 1673 int first_intf; 1674 int last_intf; 1675 int i; 1676 1677 for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) { 1678 intf_assoc = config->intf_assoc[i]; 1679 if (intf_assoc->bInterfaceCount == 0) 1680 continue; 1681 1682 first_intf = intf_assoc->bFirstInterface; 1683 last_intf = first_intf + (intf_assoc->bInterfaceCount - 1); 1684 if (inum >= first_intf && inum <= last_intf) { 1685 if (!retval) 1686 retval = intf_assoc; 1687 else 1688 dev_err(&dev->dev, "Interface #%d referenced" 1689 " by multiple IADs\n", inum); 1690 } 1691 } 1692 1693 return retval; 1694 } 1695 1696 1697 /* 1698 * Internal function to queue a device reset 1699 * See usb_queue_reset_device() for more details 1700 */ 1701 static void __usb_queue_reset_device(struct work_struct *ws) 1702 { 1703 int rc; 1704 struct usb_interface *iface = 1705 container_of(ws, struct usb_interface, reset_ws); 1706 struct usb_device *udev = interface_to_usbdev(iface); 1707 1708 rc = usb_lock_device_for_reset(udev, iface); 1709 if (rc >= 0) { 1710 usb_reset_device(udev); 1711 usb_unlock_device(udev); 1712 } 1713 usb_put_intf(iface); /* Undo _get_ in usb_queue_reset_device() */ 1714 } 1715 1716 1717 /* 1718 * usb_set_configuration - Makes a particular device setting be current 1719 * @dev: the device whose configuration is being updated 1720 * @configuration: the configuration being chosen. 1721 * Context: !in_interrupt(), caller owns the device lock 1722 * 1723 * This is used to enable non-default device modes. Not all devices 1724 * use this kind of configurability; many devices only have one 1725 * configuration. 1726 * 1727 * @configuration is the value of the configuration to be installed. 1728 * According to the USB spec (e.g. section 9.1.1.5), configuration values 1729 * must be non-zero; a value of zero indicates that the device in 1730 * unconfigured. However some devices erroneously use 0 as one of their 1731 * configuration values. To help manage such devices, this routine will 1732 * accept @configuration = -1 as indicating the device should be put in 1733 * an unconfigured state. 1734 * 1735 * USB device configurations may affect Linux interoperability, 1736 * power consumption and the functionality available. For example, 1737 * the default configuration is limited to using 100mA of bus power, 1738 * so that when certain device functionality requires more power, 1739 * and the device is bus powered, that functionality should be in some 1740 * non-default device configuration. Other device modes may also be 1741 * reflected as configuration options, such as whether two ISDN 1742 * channels are available independently; and choosing between open 1743 * standard device protocols (like CDC) or proprietary ones. 1744 * 1745 * Note that a non-authorized device (dev->authorized == 0) will only 1746 * be put in unconfigured mode. 1747 * 1748 * Note that USB has an additional level of device configurability, 1749 * associated with interfaces. That configurability is accessed using 1750 * usb_set_interface(). 1751 * 1752 * This call is synchronous. The calling context must be able to sleep, 1753 * must own the device lock, and must not hold the driver model's USB 1754 * bus mutex; usb interface driver probe() methods cannot use this routine. 1755 * 1756 * Returns zero on success, or else the status code returned by the 1757 * underlying call that failed. On successful completion, each interface 1758 * in the original device configuration has been destroyed, and each one 1759 * in the new configuration has been probed by all relevant usb device 1760 * drivers currently known to the kernel. 1761 */ 1762 int usb_set_configuration(struct usb_device *dev, int configuration) 1763 { 1764 int i, ret; 1765 struct usb_host_config *cp = NULL; 1766 struct usb_interface **new_interfaces = NULL; 1767 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1768 int n, nintf; 1769 1770 if (dev->authorized == 0 || configuration == -1) 1771 configuration = 0; 1772 else { 1773 for (i = 0; i < dev->descriptor.bNumConfigurations; i++) { 1774 if (dev->config[i].desc.bConfigurationValue == 1775 configuration) { 1776 cp = &dev->config[i]; 1777 break; 1778 } 1779 } 1780 } 1781 if ((!cp && configuration != 0)) 1782 return -EINVAL; 1783 1784 /* The USB spec says configuration 0 means unconfigured. 1785 * But if a device includes a configuration numbered 0, 1786 * we will accept it as a correctly configured state. 1787 * Use -1 if you really want to unconfigure the device. 1788 */ 1789 if (cp && configuration == 0) 1790 dev_warn(&dev->dev, "config 0 descriptor??\n"); 1791 1792 /* Allocate memory for new interfaces before doing anything else, 1793 * so that if we run out then nothing will have changed. */ 1794 n = nintf = 0; 1795 if (cp) { 1796 nintf = cp->desc.bNumInterfaces; 1797 new_interfaces = kmalloc(nintf * sizeof(*new_interfaces), 1798 GFP_NOIO); 1799 if (!new_interfaces) 1800 return -ENOMEM; 1801 1802 for (; n < nintf; ++n) { 1803 new_interfaces[n] = kzalloc( 1804 sizeof(struct usb_interface), 1805 GFP_NOIO); 1806 if (!new_interfaces[n]) { 1807 ret = -ENOMEM; 1808 free_interfaces: 1809 while (--n >= 0) 1810 kfree(new_interfaces[n]); 1811 kfree(new_interfaces); 1812 return ret; 1813 } 1814 } 1815 1816 i = dev->bus_mA - usb_get_max_power(dev, cp); 1817 if (i < 0) 1818 dev_warn(&dev->dev, "new config #%d exceeds power " 1819 "limit by %dmA\n", 1820 configuration, -i); 1821 } 1822 1823 /* Wake up the device so we can send it the Set-Config request */ 1824 ret = usb_autoresume_device(dev); 1825 if (ret) 1826 goto free_interfaces; 1827 1828 /* if it's already configured, clear out old state first. 1829 * getting rid of old interfaces means unbinding their drivers. 1830 */ 1831 if (dev->state != USB_STATE_ADDRESS) 1832 usb_disable_device(dev, 1); /* Skip ep0 */ 1833 1834 /* Get rid of pending async Set-Config requests for this device */ 1835 cancel_async_set_config(dev); 1836 1837 /* Make sure we have bandwidth (and available HCD resources) for this 1838 * configuration. Remove endpoints from the schedule if we're dropping 1839 * this configuration to set configuration 0. After this point, the 1840 * host controller will not allow submissions to dropped endpoints. If 1841 * this call fails, the device state is unchanged. 1842 */ 1843 mutex_lock(hcd->bandwidth_mutex); 1844 /* Disable LPM, and re-enable it once the new configuration is 1845 * installed, so that the xHCI driver can recalculate the U1/U2 1846 * timeouts. 1847 */ 1848 if (dev->actconfig && usb_disable_lpm(dev)) { 1849 dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__); 1850 mutex_unlock(hcd->bandwidth_mutex); 1851 ret = -ENOMEM; 1852 goto free_interfaces; 1853 } 1854 ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL); 1855 if (ret < 0) { 1856 if (dev->actconfig) 1857 usb_enable_lpm(dev); 1858 mutex_unlock(hcd->bandwidth_mutex); 1859 usb_autosuspend_device(dev); 1860 goto free_interfaces; 1861 } 1862 1863 /* 1864 * Initialize the new interface structures and the 1865 * hc/hcd/usbcore interface/endpoint state. 1866 */ 1867 for (i = 0; i < nintf; ++i) { 1868 struct usb_interface_cache *intfc; 1869 struct usb_interface *intf; 1870 struct usb_host_interface *alt; 1871 1872 cp->interface[i] = intf = new_interfaces[i]; 1873 intfc = cp->intf_cache[i]; 1874 intf->altsetting = intfc->altsetting; 1875 intf->num_altsetting = intfc->num_altsetting; 1876 intf->authorized = !!HCD_INTF_AUTHORIZED(hcd); 1877 kref_get(&intfc->ref); 1878 1879 alt = usb_altnum_to_altsetting(intf, 0); 1880 1881 /* No altsetting 0? We'll assume the first altsetting. 1882 * We could use a GetInterface call, but if a device is 1883 * so non-compliant that it doesn't have altsetting 0 1884 * then I wouldn't trust its reply anyway. 1885 */ 1886 if (!alt) 1887 alt = &intf->altsetting[0]; 1888 1889 intf->intf_assoc = 1890 find_iad(dev, cp, alt->desc.bInterfaceNumber); 1891 intf->cur_altsetting = alt; 1892 usb_enable_interface(dev, intf, true); 1893 intf->dev.parent = &dev->dev; 1894 intf->dev.driver = NULL; 1895 intf->dev.bus = &usb_bus_type; 1896 intf->dev.type = &usb_if_device_type; 1897 intf->dev.groups = usb_interface_groups; 1898 /* 1899 * Please refer to usb_alloc_dev() to see why we set 1900 * dma_mask and dma_pfn_offset. 1901 */ 1902 intf->dev.dma_mask = dev->dev.dma_mask; 1903 intf->dev.dma_pfn_offset = dev->dev.dma_pfn_offset; 1904 INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); 1905 intf->minor = -1; 1906 device_initialize(&intf->dev); 1907 pm_runtime_no_callbacks(&intf->dev); 1908 dev_set_name(&intf->dev, "%d-%s:%d.%d", 1909 dev->bus->busnum, dev->devpath, 1910 configuration, alt->desc.bInterfaceNumber); 1911 usb_get_dev(dev); 1912 } 1913 kfree(new_interfaces); 1914 1915 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1916 USB_REQ_SET_CONFIGURATION, 0, configuration, 0, 1917 NULL, 0, USB_CTRL_SET_TIMEOUT); 1918 if (ret < 0 && cp) { 1919 /* 1920 * All the old state is gone, so what else can we do? 1921 * The device is probably useless now anyway. 1922 */ 1923 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1924 for (i = 0; i < nintf; ++i) { 1925 usb_disable_interface(dev, cp->interface[i], true); 1926 put_device(&cp->interface[i]->dev); 1927 cp->interface[i] = NULL; 1928 } 1929 cp = NULL; 1930 } 1931 1932 dev->actconfig = cp; 1933 mutex_unlock(hcd->bandwidth_mutex); 1934 1935 if (!cp) { 1936 usb_set_device_state(dev, USB_STATE_ADDRESS); 1937 1938 /* Leave LPM disabled while the device is unconfigured. */ 1939 usb_autosuspend_device(dev); 1940 return ret; 1941 } 1942 usb_set_device_state(dev, USB_STATE_CONFIGURED); 1943 1944 if (cp->string == NULL && 1945 !(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS)) 1946 cp->string = usb_cache_string(dev, cp->desc.iConfiguration); 1947 1948 /* Now that the interfaces are installed, re-enable LPM. */ 1949 usb_unlocked_enable_lpm(dev); 1950 /* Enable LTM if it was turned off by usb_disable_device. */ 1951 usb_enable_ltm(dev); 1952 1953 /* Now that all the interfaces are set up, register them 1954 * to trigger binding of drivers to interfaces. probe() 1955 * routines may install different altsettings and may 1956 * claim() any interfaces not yet bound. Many class drivers 1957 * need that: CDC, audio, video, etc. 1958 */ 1959 for (i = 0; i < nintf; ++i) { 1960 struct usb_interface *intf = cp->interface[i]; 1961 1962 dev_dbg(&dev->dev, 1963 "adding %s (config #%d, interface %d)\n", 1964 dev_name(&intf->dev), configuration, 1965 intf->cur_altsetting->desc.bInterfaceNumber); 1966 device_enable_async_suspend(&intf->dev); 1967 ret = device_add(&intf->dev); 1968 if (ret != 0) { 1969 dev_err(&dev->dev, "device_add(%s) --> %d\n", 1970 dev_name(&intf->dev), ret); 1971 continue; 1972 } 1973 create_intf_ep_devs(intf); 1974 } 1975 1976 usb_autosuspend_device(dev); 1977 return 0; 1978 } 1979 EXPORT_SYMBOL_GPL(usb_set_configuration); 1980 1981 static LIST_HEAD(set_config_list); 1982 static DEFINE_SPINLOCK(set_config_lock); 1983 1984 struct set_config_request { 1985 struct usb_device *udev; 1986 int config; 1987 struct work_struct work; 1988 struct list_head node; 1989 }; 1990 1991 /* Worker routine for usb_driver_set_configuration() */ 1992 static void driver_set_config_work(struct work_struct *work) 1993 { 1994 struct set_config_request *req = 1995 container_of(work, struct set_config_request, work); 1996 struct usb_device *udev = req->udev; 1997 1998 usb_lock_device(udev); 1999 spin_lock(&set_config_lock); 2000 list_del(&req->node); 2001 spin_unlock(&set_config_lock); 2002 2003 if (req->config >= -1) /* Is req still valid? */ 2004 usb_set_configuration(udev, req->config); 2005 usb_unlock_device(udev); 2006 usb_put_dev(udev); 2007 kfree(req); 2008 } 2009 2010 /* Cancel pending Set-Config requests for a device whose configuration 2011 * was just changed 2012 */ 2013 static void cancel_async_set_config(struct usb_device *udev) 2014 { 2015 struct set_config_request *req; 2016 2017 spin_lock(&set_config_lock); 2018 list_for_each_entry(req, &set_config_list, node) { 2019 if (req->udev == udev) 2020 req->config = -999; /* Mark as cancelled */ 2021 } 2022 spin_unlock(&set_config_lock); 2023 } 2024 2025 /** 2026 * usb_driver_set_configuration - Provide a way for drivers to change device configurations 2027 * @udev: the device whose configuration is being updated 2028 * @config: the configuration being chosen. 2029 * Context: In process context, must be able to sleep 2030 * 2031 * Device interface drivers are not allowed to change device configurations. 2032 * This is because changing configurations will destroy the interface the 2033 * driver is bound to and create new ones; it would be like a floppy-disk 2034 * driver telling the computer to replace the floppy-disk drive with a 2035 * tape drive! 2036 * 2037 * Still, in certain specialized circumstances the need may arise. This 2038 * routine gets around the normal restrictions by using a work thread to 2039 * submit the change-config request. 2040 * 2041 * Return: 0 if the request was successfully queued, error code otherwise. 2042 * The caller has no way to know whether the queued request will eventually 2043 * succeed. 2044 */ 2045 int usb_driver_set_configuration(struct usb_device *udev, int config) 2046 { 2047 struct set_config_request *req; 2048 2049 req = kmalloc(sizeof(*req), GFP_KERNEL); 2050 if (!req) 2051 return -ENOMEM; 2052 req->udev = udev; 2053 req->config = config; 2054 INIT_WORK(&req->work, driver_set_config_work); 2055 2056 spin_lock(&set_config_lock); 2057 list_add(&req->node, &set_config_list); 2058 spin_unlock(&set_config_lock); 2059 2060 usb_get_dev(udev); 2061 schedule_work(&req->work); 2062 return 0; 2063 } 2064 EXPORT_SYMBOL_GPL(usb_driver_set_configuration); 2065 2066 /** 2067 * cdc_parse_cdc_header - parse the extra headers present in CDC devices 2068 * @hdr: the place to put the results of the parsing 2069 * @intf: the interface for which parsing is requested 2070 * @buffer: pointer to the extra headers to be parsed 2071 * @buflen: length of the extra headers 2072 * 2073 * This evaluates the extra headers present in CDC devices which 2074 * bind the interfaces for data and control and provide details 2075 * about the capabilities of the device. 2076 * 2077 * Return: number of descriptors parsed or -EINVAL 2078 * if the header is contradictory beyond salvage 2079 */ 2080 2081 int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, 2082 struct usb_interface *intf, 2083 u8 *buffer, 2084 int buflen) 2085 { 2086 /* duplicates are ignored */ 2087 struct usb_cdc_union_desc *union_header = NULL; 2088 2089 /* duplicates are not tolerated */ 2090 struct usb_cdc_header_desc *header = NULL; 2091 struct usb_cdc_ether_desc *ether = NULL; 2092 struct usb_cdc_mdlm_detail_desc *detail = NULL; 2093 struct usb_cdc_mdlm_desc *desc = NULL; 2094 2095 unsigned int elength; 2096 int cnt = 0; 2097 2098 memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header)); 2099 hdr->phonet_magic_present = false; 2100 while (buflen > 0) { 2101 elength = buffer[0]; 2102 if (!elength) { 2103 dev_err(&intf->dev, "skipping garbage byte\n"); 2104 elength = 1; 2105 goto next_desc; 2106 } 2107 if ((buflen < elength) || (elength < 3)) { 2108 dev_err(&intf->dev, "invalid descriptor buffer length\n"); 2109 break; 2110 } 2111 if (buffer[1] != USB_DT_CS_INTERFACE) { 2112 dev_err(&intf->dev, "skipping garbage\n"); 2113 goto next_desc; 2114 } 2115 2116 switch (buffer[2]) { 2117 case USB_CDC_UNION_TYPE: /* we've found it */ 2118 if (elength < sizeof(struct usb_cdc_union_desc)) 2119 goto next_desc; 2120 if (union_header) { 2121 dev_err(&intf->dev, "More than one union descriptor, skipping ...\n"); 2122 goto next_desc; 2123 } 2124 union_header = (struct usb_cdc_union_desc *)buffer; 2125 break; 2126 case USB_CDC_COUNTRY_TYPE: 2127 if (elength < sizeof(struct usb_cdc_country_functional_desc)) 2128 goto next_desc; 2129 hdr->usb_cdc_country_functional_desc = 2130 (struct usb_cdc_country_functional_desc *)buffer; 2131 break; 2132 case USB_CDC_HEADER_TYPE: 2133 if (elength != sizeof(struct usb_cdc_header_desc)) 2134 goto next_desc; 2135 if (header) 2136 return -EINVAL; 2137 header = (struct usb_cdc_header_desc *)buffer; 2138 break; 2139 case USB_CDC_ACM_TYPE: 2140 if (elength < sizeof(struct usb_cdc_acm_descriptor)) 2141 goto next_desc; 2142 hdr->usb_cdc_acm_descriptor = 2143 (struct usb_cdc_acm_descriptor *)buffer; 2144 break; 2145 case USB_CDC_ETHERNET_TYPE: 2146 if (elength != sizeof(struct usb_cdc_ether_desc)) 2147 goto next_desc; 2148 if (ether) 2149 return -EINVAL; 2150 ether = (struct usb_cdc_ether_desc *)buffer; 2151 break; 2152 case USB_CDC_CALL_MANAGEMENT_TYPE: 2153 if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor)) 2154 goto next_desc; 2155 hdr->usb_cdc_call_mgmt_descriptor = 2156 (struct usb_cdc_call_mgmt_descriptor *)buffer; 2157 break; 2158 case USB_CDC_DMM_TYPE: 2159 if (elength < sizeof(struct usb_cdc_dmm_desc)) 2160 goto next_desc; 2161 hdr->usb_cdc_dmm_desc = 2162 (struct usb_cdc_dmm_desc *)buffer; 2163 break; 2164 case USB_CDC_MDLM_TYPE: 2165 if (elength < sizeof(struct usb_cdc_mdlm_desc *)) 2166 goto next_desc; 2167 if (desc) 2168 return -EINVAL; 2169 desc = (struct usb_cdc_mdlm_desc *)buffer; 2170 break; 2171 case USB_CDC_MDLM_DETAIL_TYPE: 2172 if (elength < sizeof(struct usb_cdc_mdlm_detail_desc *)) 2173 goto next_desc; 2174 if (detail) 2175 return -EINVAL; 2176 detail = (struct usb_cdc_mdlm_detail_desc *)buffer; 2177 break; 2178 case USB_CDC_NCM_TYPE: 2179 if (elength < sizeof(struct usb_cdc_ncm_desc)) 2180 goto next_desc; 2181 hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer; 2182 break; 2183 case USB_CDC_MBIM_TYPE: 2184 if (elength < sizeof(struct usb_cdc_mbim_desc)) 2185 goto next_desc; 2186 2187 hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer; 2188 break; 2189 case USB_CDC_MBIM_EXTENDED_TYPE: 2190 if (elength < sizeof(struct usb_cdc_mbim_extended_desc)) 2191 break; 2192 hdr->usb_cdc_mbim_extended_desc = 2193 (struct usb_cdc_mbim_extended_desc *)buffer; 2194 break; 2195 case CDC_PHONET_MAGIC_NUMBER: 2196 hdr->phonet_magic_present = true; 2197 break; 2198 default: 2199 /* 2200 * there are LOTS more CDC descriptors that 2201 * could legitimately be found here. 2202 */ 2203 dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n", 2204 buffer[2], elength); 2205 goto next_desc; 2206 } 2207 cnt++; 2208 next_desc: 2209 buflen -= elength; 2210 buffer += elength; 2211 } 2212 hdr->usb_cdc_union_desc = union_header; 2213 hdr->usb_cdc_header_desc = header; 2214 hdr->usb_cdc_mdlm_detail_desc = detail; 2215 hdr->usb_cdc_mdlm_desc = desc; 2216 hdr->usb_cdc_ether_desc = ether; 2217 return cnt; 2218 } 2219 2220 EXPORT_SYMBOL(cdc_parse_cdc_header); 2221