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/acpi.h> 9 #include <linux/pci.h> /* for scatterlist macros */ 10 #include <linux/usb.h> 11 #include <linux/module.h> 12 #include <linux/slab.h> 13 #include <linux/mm.h> 14 #include <linux/timer.h> 15 #include <linux/ctype.h> 16 #include <linux/nls.h> 17 #include <linux/device.h> 18 #include <linux/scatterlist.h> 19 #include <linux/usb/cdc.h> 20 #include <linux/usb/quirks.h> 21 #include <linux/usb/hcd.h> /* for usbcore internals */ 22 #include <linux/usb/of.h> 23 #include <asm/byteorder.h> 24 25 #include "usb.h" 26 27 static void cancel_async_set_config(struct usb_device *udev); 28 29 struct api_context { 30 struct completion done; 31 int status; 32 }; 33 34 static void usb_api_blocking_completion(struct urb *urb) 35 { 36 struct api_context *ctx = urb->context; 37 38 ctx->status = urb->status; 39 complete(&ctx->done); 40 } 41 42 43 /* 44 * Starts urb and waits for completion or timeout. Note that this call 45 * is NOT interruptible. Many device driver i/o requests should be 46 * interruptible and therefore these drivers should implement their 47 * own interruptible routines. 48 */ 49 static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) 50 { 51 struct api_context ctx; 52 unsigned long expire; 53 int retval; 54 55 init_completion(&ctx.done); 56 urb->context = &ctx; 57 urb->actual_length = 0; 58 retval = usb_submit_urb(urb, GFP_NOIO); 59 if (unlikely(retval)) 60 goto out; 61 62 expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT; 63 if (!wait_for_completion_timeout(&ctx.done, expire)) { 64 usb_kill_urb(urb); 65 retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status); 66 67 dev_dbg(&urb->dev->dev, 68 "%s timed out on ep%d%s len=%u/%u\n", 69 current->comm, 70 usb_endpoint_num(&urb->ep->desc), 71 usb_urb_dir_in(urb) ? "in" : "out", 72 urb->actual_length, 73 urb->transfer_buffer_length); 74 } else 75 retval = ctx.status; 76 out: 77 if (actual_length) 78 *actual_length = urb->actual_length; 79 80 usb_free_urb(urb); 81 return retval; 82 } 83 84 /*-------------------------------------------------------------------*/ 85 /* returns status (negative) or length (positive) */ 86 static int usb_internal_control_msg(struct usb_device *usb_dev, 87 unsigned int pipe, 88 struct usb_ctrlrequest *cmd, 89 void *data, int len, int timeout) 90 { 91 struct urb *urb; 92 int retv; 93 int length; 94 95 urb = usb_alloc_urb(0, GFP_NOIO); 96 if (!urb) 97 return -ENOMEM; 98 99 usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data, 100 len, usb_api_blocking_completion, NULL); 101 102 retv = usb_start_wait_urb(urb, timeout, &length); 103 if (retv < 0) 104 return retv; 105 else 106 return length; 107 } 108 109 /** 110 * usb_control_msg - Builds a control urb, sends it off and waits for completion 111 * @dev: pointer to the usb device to send the message to 112 * @pipe: endpoint "pipe" to send the message to 113 * @request: USB message request value 114 * @requesttype: USB message request type value 115 * @value: USB message value 116 * @index: USB message index value 117 * @data: pointer to the data to send 118 * @size: length in bytes of the data to send 119 * @timeout: time in msecs to wait for the message to complete before timing 120 * out (if 0 the wait is forever) 121 * 122 * Context: !in_interrupt () 123 * 124 * This function sends a simple control message to a specified endpoint and 125 * waits for the message to complete, or timeout. 126 * 127 * Don't use this function from within an interrupt context. If you need 128 * an asynchronous message, or need to send a message from within interrupt 129 * context, use usb_submit_urb(). If a thread in your driver uses this call, 130 * make sure your disconnect() method can wait for it to complete. Since you 131 * don't have a handle on the URB used, you can't cancel the request. 132 * 133 * Return: If successful, the number of bytes transferred. Otherwise, a negative 134 * error number. 135 */ 136 int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, 137 __u8 requesttype, __u16 value, __u16 index, void *data, 138 __u16 size, int timeout) 139 { 140 struct usb_ctrlrequest *dr; 141 int ret; 142 143 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); 144 if (!dr) 145 return -ENOMEM; 146 147 dr->bRequestType = requesttype; 148 dr->bRequest = request; 149 dr->wValue = cpu_to_le16(value); 150 dr->wIndex = cpu_to_le16(index); 151 dr->wLength = cpu_to_le16(size); 152 153 ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout); 154 155 /* Linger a bit, prior to the next control message. */ 156 if (dev->quirks & USB_QUIRK_DELAY_CTRL_MSG) 157 msleep(200); 158 159 kfree(dr); 160 161 return ret; 162 } 163 EXPORT_SYMBOL_GPL(usb_control_msg); 164 165 /** 166 * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion 167 * @usb_dev: pointer to the usb device to send the message to 168 * @pipe: endpoint "pipe" to send the message to 169 * @data: pointer to the data to send 170 * @len: length in bytes of the data to send 171 * @actual_length: pointer to a location to put the actual length transferred 172 * in bytes 173 * @timeout: time in msecs to wait for the message to complete before 174 * timing out (if 0 the wait is forever) 175 * 176 * Context: !in_interrupt () 177 * 178 * This function sends a simple interrupt message to a specified endpoint and 179 * waits for the message to complete, or timeout. 180 * 181 * Don't use this function from within an interrupt context. If you need 182 * an asynchronous message, or need to send a message from within interrupt 183 * context, use usb_submit_urb() If a thread in your driver uses this call, 184 * make sure your disconnect() method can wait for it to complete. Since you 185 * don't have a handle on the URB used, you can't cancel the request. 186 * 187 * Return: 188 * If successful, 0. Otherwise a negative error number. The number of actual 189 * bytes transferred will be stored in the @actual_length parameter. 190 */ 191 int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe, 192 void *data, int len, int *actual_length, int timeout) 193 { 194 return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout); 195 } 196 EXPORT_SYMBOL_GPL(usb_interrupt_msg); 197 198 /** 199 * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion 200 * @usb_dev: pointer to the usb device to send the message to 201 * @pipe: endpoint "pipe" to send the message to 202 * @data: pointer to the data to send 203 * @len: length in bytes of the data to send 204 * @actual_length: pointer to a location to put the actual length transferred 205 * in bytes 206 * @timeout: time in msecs to wait for the message to complete before 207 * timing out (if 0 the wait is forever) 208 * 209 * Context: !in_interrupt () 210 * 211 * This function sends a simple bulk message to a specified endpoint 212 * and waits for the message to complete, or timeout. 213 * 214 * Don't use this function from within an interrupt context. If you need 215 * an asynchronous message, or need to send a message from within interrupt 216 * context, use usb_submit_urb() If a thread in your driver uses this call, 217 * make sure your disconnect() method can wait for it to complete. Since you 218 * don't have a handle on the URB used, you can't cancel the request. 219 * 220 * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT ioctl, 221 * users are forced to abuse this routine by using it to submit URBs for 222 * interrupt endpoints. We will take the liberty of creating an interrupt URB 223 * (with the default interval) if the target is an interrupt endpoint. 224 * 225 * Return: 226 * If successful, 0. Otherwise a negative error number. The number of actual 227 * bytes transferred will be stored in the @actual_length parameter. 228 * 229 */ 230 int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, 231 void *data, int len, int *actual_length, int timeout) 232 { 233 struct urb *urb; 234 struct usb_host_endpoint *ep; 235 236 ep = usb_pipe_endpoint(usb_dev, pipe); 237 if (!ep || len < 0) 238 return -EINVAL; 239 240 urb = usb_alloc_urb(0, GFP_KERNEL); 241 if (!urb) 242 return -ENOMEM; 243 244 if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == 245 USB_ENDPOINT_XFER_INT) { 246 pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30); 247 usb_fill_int_urb(urb, usb_dev, pipe, data, len, 248 usb_api_blocking_completion, NULL, 249 ep->desc.bInterval); 250 } else 251 usb_fill_bulk_urb(urb, usb_dev, pipe, data, len, 252 usb_api_blocking_completion, NULL); 253 254 return usb_start_wait_urb(urb, timeout, actual_length); 255 } 256 EXPORT_SYMBOL_GPL(usb_bulk_msg); 257 258 /*-------------------------------------------------------------------*/ 259 260 static void sg_clean(struct usb_sg_request *io) 261 { 262 if (io->urbs) { 263 while (io->entries--) 264 usb_free_urb(io->urbs[io->entries]); 265 kfree(io->urbs); 266 io->urbs = NULL; 267 } 268 io->dev = NULL; 269 } 270 271 static void sg_complete(struct urb *urb) 272 { 273 unsigned long flags; 274 struct usb_sg_request *io = urb->context; 275 int status = urb->status; 276 277 spin_lock_irqsave(&io->lock, flags); 278 279 /* In 2.5 we require hcds' endpoint queues not to progress after fault 280 * reports, until the completion callback (this!) returns. That lets 281 * device driver code (like this routine) unlink queued urbs first, 282 * if it needs to, since the HC won't work on them at all. So it's 283 * not possible for page N+1 to overwrite page N, and so on. 284 * 285 * That's only for "hard" faults; "soft" faults (unlinks) sometimes 286 * complete before the HCD can get requests away from hardware, 287 * though never during cleanup after a hard fault. 288 */ 289 if (io->status 290 && (io->status != -ECONNRESET 291 || status != -ECONNRESET) 292 && urb->actual_length) { 293 dev_err(io->dev->bus->controller, 294 "dev %s ep%d%s scatterlist error %d/%d\n", 295 io->dev->devpath, 296 usb_endpoint_num(&urb->ep->desc), 297 usb_urb_dir_in(urb) ? "in" : "out", 298 status, io->status); 299 /* BUG (); */ 300 } 301 302 if (io->status == 0 && status && status != -ECONNRESET) { 303 int i, found, retval; 304 305 io->status = status; 306 307 /* the previous urbs, and this one, completed already. 308 * unlink pending urbs so they won't rx/tx bad data. 309 * careful: unlink can sometimes be synchronous... 310 */ 311 spin_unlock_irqrestore(&io->lock, flags); 312 for (i = 0, found = 0; i < io->entries; i++) { 313 if (!io->urbs[i]) 314 continue; 315 if (found) { 316 usb_block_urb(io->urbs[i]); 317 retval = usb_unlink_urb(io->urbs[i]); 318 if (retval != -EINPROGRESS && 319 retval != -ENODEV && 320 retval != -EBUSY && 321 retval != -EIDRM) 322 dev_err(&io->dev->dev, 323 "%s, unlink --> %d\n", 324 __func__, retval); 325 } else if (urb == io->urbs[i]) 326 found = 1; 327 } 328 spin_lock_irqsave(&io->lock, flags); 329 } 330 331 /* on the last completion, signal usb_sg_wait() */ 332 io->bytes += urb->actual_length; 333 io->count--; 334 if (!io->count) 335 complete(&io->complete); 336 337 spin_unlock_irqrestore(&io->lock, flags); 338 } 339 340 341 /** 342 * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request 343 * @io: request block being initialized. until usb_sg_wait() returns, 344 * treat this as a pointer to an opaque block of memory, 345 * @dev: the usb device that will send or receive the data 346 * @pipe: endpoint "pipe" used to transfer the data 347 * @period: polling rate for interrupt endpoints, in frames or 348 * (for high speed endpoints) microframes; ignored for bulk 349 * @sg: scatterlist entries 350 * @nents: how many entries in the scatterlist 351 * @length: how many bytes to send from the scatterlist, or zero to 352 * send every byte identified in the list. 353 * @mem_flags: SLAB_* flags affecting memory allocations in this call 354 * 355 * This initializes a scatter/gather request, allocating resources such as 356 * I/O mappings and urb memory (except maybe memory used by USB controller 357 * drivers). 358 * 359 * The request must be issued using usb_sg_wait(), which waits for the I/O to 360 * complete (or to be canceled) and then cleans up all resources allocated by 361 * usb_sg_init(). 362 * 363 * The request may be canceled with usb_sg_cancel(), either before or after 364 * usb_sg_wait() is called. 365 * 366 * Return: Zero for success, else a negative errno value. 367 */ 368 int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev, 369 unsigned pipe, unsigned period, struct scatterlist *sg, 370 int nents, size_t length, gfp_t mem_flags) 371 { 372 int i; 373 int urb_flags; 374 int use_sg; 375 376 if (!io || !dev || !sg 377 || usb_pipecontrol(pipe) 378 || usb_pipeisoc(pipe) 379 || nents <= 0) 380 return -EINVAL; 381 382 spin_lock_init(&io->lock); 383 io->dev = dev; 384 io->pipe = pipe; 385 386 if (dev->bus->sg_tablesize > 0) { 387 use_sg = true; 388 io->entries = 1; 389 } else { 390 use_sg = false; 391 io->entries = nents; 392 } 393 394 /* initialize all the urbs we'll use */ 395 io->urbs = kmalloc_array(io->entries, sizeof(*io->urbs), mem_flags); 396 if (!io->urbs) 397 goto nomem; 398 399 urb_flags = URB_NO_INTERRUPT; 400 if (usb_pipein(pipe)) 401 urb_flags |= URB_SHORT_NOT_OK; 402 403 for_each_sg(sg, sg, io->entries, i) { 404 struct urb *urb; 405 unsigned len; 406 407 urb = usb_alloc_urb(0, mem_flags); 408 if (!urb) { 409 io->entries = i; 410 goto nomem; 411 } 412 io->urbs[i] = urb; 413 414 urb->dev = NULL; 415 urb->pipe = pipe; 416 urb->interval = period; 417 urb->transfer_flags = urb_flags; 418 urb->complete = sg_complete; 419 urb->context = io; 420 urb->sg = sg; 421 422 if (use_sg) { 423 /* There is no single transfer buffer */ 424 urb->transfer_buffer = NULL; 425 urb->num_sgs = nents; 426 427 /* A length of zero means transfer the whole sg list */ 428 len = length; 429 if (len == 0) { 430 struct scatterlist *sg2; 431 int j; 432 433 for_each_sg(sg, sg2, nents, j) 434 len += sg2->length; 435 } 436 } else { 437 /* 438 * Some systems can't use DMA; they use PIO instead. 439 * For their sakes, transfer_buffer is set whenever 440 * possible. 441 */ 442 if (!PageHighMem(sg_page(sg))) 443 urb->transfer_buffer = sg_virt(sg); 444 else 445 urb->transfer_buffer = NULL; 446 447 len = sg->length; 448 if (length) { 449 len = min_t(size_t, len, length); 450 length -= len; 451 if (length == 0) 452 io->entries = i + 1; 453 } 454 } 455 urb->transfer_buffer_length = len; 456 } 457 io->urbs[--i]->transfer_flags &= ~URB_NO_INTERRUPT; 458 459 /* transaction state */ 460 io->count = io->entries; 461 io->status = 0; 462 io->bytes = 0; 463 init_completion(&io->complete); 464 return 0; 465 466 nomem: 467 sg_clean(io); 468 return -ENOMEM; 469 } 470 EXPORT_SYMBOL_GPL(usb_sg_init); 471 472 /** 473 * usb_sg_wait - synchronously execute scatter/gather request 474 * @io: request block handle, as initialized with usb_sg_init(). 475 * some fields become accessible when this call returns. 476 * Context: !in_interrupt () 477 * 478 * This function blocks until the specified I/O operation completes. It 479 * leverages the grouping of the related I/O requests to get good transfer 480 * rates, by queueing the requests. At higher speeds, such queuing can 481 * significantly improve USB throughput. 482 * 483 * There are three kinds of completion for this function. 484 * 485 * (1) success, where io->status is zero. The number of io->bytes 486 * transferred is as requested. 487 * (2) error, where io->status is a negative errno value. The number 488 * of io->bytes transferred before the error is usually less 489 * than requested, and can be nonzero. 490 * (3) cancellation, a type of error with status -ECONNRESET that 491 * is initiated by usb_sg_cancel(). 492 * 493 * When this function returns, all memory allocated through usb_sg_init() or 494 * this call will have been freed. The request block parameter may still be 495 * passed to usb_sg_cancel(), or it may be freed. It could also be 496 * reinitialized and then reused. 497 * 498 * Data Transfer Rates: 499 * 500 * Bulk transfers are valid for full or high speed endpoints. 501 * The best full speed data rate is 19 packets of 64 bytes each 502 * per frame, or 1216 bytes per millisecond. 503 * The best high speed data rate is 13 packets of 512 bytes each 504 * per microframe, or 52 KBytes per millisecond. 505 * 506 * The reason to use interrupt transfers through this API would most likely 507 * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond 508 * could be transferred. That capability is less useful for low or full 509 * speed interrupt endpoints, which allow at most one packet per millisecond, 510 * of at most 8 or 64 bytes (respectively). 511 * 512 * It is not necessary to call this function to reserve bandwidth for devices 513 * under an xHCI host controller, as the bandwidth is reserved when the 514 * configuration or interface alt setting is selected. 515 */ 516 void usb_sg_wait(struct usb_sg_request *io) 517 { 518 int i; 519 int entries = io->entries; 520 521 /* queue the urbs. */ 522 spin_lock_irq(&io->lock); 523 i = 0; 524 while (i < entries && !io->status) { 525 int retval; 526 527 io->urbs[i]->dev = io->dev; 528 spin_unlock_irq(&io->lock); 529 530 retval = usb_submit_urb(io->urbs[i], GFP_NOIO); 531 532 switch (retval) { 533 /* maybe we retrying will recover */ 534 case -ENXIO: /* hc didn't queue this one */ 535 case -EAGAIN: 536 case -ENOMEM: 537 retval = 0; 538 yield(); 539 break; 540 541 /* no error? continue immediately. 542 * 543 * NOTE: to work better with UHCI (4K I/O buffer may 544 * need 3K of TDs) it may be good to limit how many 545 * URBs are queued at once; N milliseconds? 546 */ 547 case 0: 548 ++i; 549 cpu_relax(); 550 break; 551 552 /* fail any uncompleted urbs */ 553 default: 554 io->urbs[i]->status = retval; 555 dev_dbg(&io->dev->dev, "%s, submit --> %d\n", 556 __func__, retval); 557 usb_sg_cancel(io); 558 } 559 spin_lock_irq(&io->lock); 560 if (retval && (io->status == 0 || io->status == -ECONNRESET)) 561 io->status = retval; 562 } 563 io->count -= entries - i; 564 if (io->count == 0) 565 complete(&io->complete); 566 spin_unlock_irq(&io->lock); 567 568 /* OK, yes, this could be packaged as non-blocking. 569 * So could the submit loop above ... but it's easier to 570 * solve neither problem than to solve both! 571 */ 572 wait_for_completion(&io->complete); 573 574 sg_clean(io); 575 } 576 EXPORT_SYMBOL_GPL(usb_sg_wait); 577 578 /** 579 * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait() 580 * @io: request block, initialized with usb_sg_init() 581 * 582 * This stops a request after it has been started by usb_sg_wait(). 583 * It can also prevents one initialized by usb_sg_init() from starting, 584 * so that call just frees resources allocated to the request. 585 */ 586 void usb_sg_cancel(struct usb_sg_request *io) 587 { 588 unsigned long flags; 589 int i, retval; 590 591 spin_lock_irqsave(&io->lock, flags); 592 if (io->status || io->count == 0) { 593 spin_unlock_irqrestore(&io->lock, flags); 594 return; 595 } 596 /* shut everything down */ 597 io->status = -ECONNRESET; 598 io->count++; /* Keep the request alive until we're done */ 599 spin_unlock_irqrestore(&io->lock, flags); 600 601 for (i = io->entries - 1; i >= 0; --i) { 602 usb_block_urb(io->urbs[i]); 603 604 retval = usb_unlink_urb(io->urbs[i]); 605 if (retval != -EINPROGRESS 606 && retval != -ENODEV 607 && retval != -EBUSY 608 && retval != -EIDRM) 609 dev_warn(&io->dev->dev, "%s, unlink --> %d\n", 610 __func__, retval); 611 } 612 613 spin_lock_irqsave(&io->lock, flags); 614 io->count--; 615 if (!io->count) 616 complete(&io->complete); 617 spin_unlock_irqrestore(&io->lock, flags); 618 } 619 EXPORT_SYMBOL_GPL(usb_sg_cancel); 620 621 /*-------------------------------------------------------------------*/ 622 623 /** 624 * usb_get_descriptor - issues a generic GET_DESCRIPTOR request 625 * @dev: the device whose descriptor is being retrieved 626 * @type: the descriptor type (USB_DT_*) 627 * @index: the number of the descriptor 628 * @buf: where to put the descriptor 629 * @size: how big is "buf"? 630 * Context: !in_interrupt () 631 * 632 * Gets a USB descriptor. Convenience functions exist to simplify 633 * getting some types of descriptors. Use 634 * usb_get_string() or usb_string() for USB_DT_STRING. 635 * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG) 636 * are part of the device structure. 637 * In addition to a number of USB-standard descriptors, some 638 * devices also use class-specific or vendor-specific descriptors. 639 * 640 * This call is synchronous, and may not be used in an interrupt context. 641 * 642 * Return: The number of bytes received on success, or else the status code 643 * returned by the underlying usb_control_msg() call. 644 */ 645 int usb_get_descriptor(struct usb_device *dev, unsigned char type, 646 unsigned char index, void *buf, int size) 647 { 648 int i; 649 int result; 650 651 memset(buf, 0, size); /* Make sure we parse really received data */ 652 653 for (i = 0; i < 3; ++i) { 654 /* retry on length 0 or error; some devices are flakey */ 655 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 656 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, 657 (type << 8) + index, 0, buf, size, 658 USB_CTRL_GET_TIMEOUT); 659 if (result <= 0 && result != -ETIMEDOUT) 660 continue; 661 if (result > 1 && ((u8 *)buf)[1] != type) { 662 result = -ENODATA; 663 continue; 664 } 665 break; 666 } 667 return result; 668 } 669 EXPORT_SYMBOL_GPL(usb_get_descriptor); 670 671 /** 672 * usb_get_string - gets a string descriptor 673 * @dev: the device whose string descriptor is being retrieved 674 * @langid: code for language chosen (from string descriptor zero) 675 * @index: the number of the descriptor 676 * @buf: where to put the string 677 * @size: how big is "buf"? 678 * Context: !in_interrupt () 679 * 680 * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character, 681 * in little-endian byte order). 682 * The usb_string() function will often be a convenient way to turn 683 * these strings into kernel-printable form. 684 * 685 * Strings may be referenced in device, configuration, interface, or other 686 * descriptors, and could also be used in vendor-specific ways. 687 * 688 * This call is synchronous, and may not be used in an interrupt context. 689 * 690 * Return: The number of bytes received on success, or else the status code 691 * returned by the underlying usb_control_msg() call. 692 */ 693 static int usb_get_string(struct usb_device *dev, unsigned short langid, 694 unsigned char index, void *buf, int size) 695 { 696 int i; 697 int result; 698 699 for (i = 0; i < 3; ++i) { 700 /* retry on length 0 or stall; some devices are flakey */ 701 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 702 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, 703 (USB_DT_STRING << 8) + index, langid, buf, size, 704 USB_CTRL_GET_TIMEOUT); 705 if (result == 0 || result == -EPIPE) 706 continue; 707 if (result > 1 && ((u8 *) buf)[1] != USB_DT_STRING) { 708 result = -ENODATA; 709 continue; 710 } 711 break; 712 } 713 return result; 714 } 715 716 static void usb_try_string_workarounds(unsigned char *buf, int *length) 717 { 718 int newlength, oldlength = *length; 719 720 for (newlength = 2; newlength + 1 < oldlength; newlength += 2) 721 if (!isprint(buf[newlength]) || buf[newlength + 1]) 722 break; 723 724 if (newlength > 2) { 725 buf[0] = newlength; 726 *length = newlength; 727 } 728 } 729 730 static int usb_string_sub(struct usb_device *dev, unsigned int langid, 731 unsigned int index, unsigned char *buf) 732 { 733 int rc; 734 735 /* Try to read the string descriptor by asking for the maximum 736 * possible number of bytes */ 737 if (dev->quirks & USB_QUIRK_STRING_FETCH_255) 738 rc = -EIO; 739 else 740 rc = usb_get_string(dev, langid, index, buf, 255); 741 742 /* If that failed try to read the descriptor length, then 743 * ask for just that many bytes */ 744 if (rc < 2) { 745 rc = usb_get_string(dev, langid, index, buf, 2); 746 if (rc == 2) 747 rc = usb_get_string(dev, langid, index, buf, buf[0]); 748 } 749 750 if (rc >= 2) { 751 if (!buf[0] && !buf[1]) 752 usb_try_string_workarounds(buf, &rc); 753 754 /* There might be extra junk at the end of the descriptor */ 755 if (buf[0] < rc) 756 rc = buf[0]; 757 758 rc = rc - (rc & 1); /* force a multiple of two */ 759 } 760 761 if (rc < 2) 762 rc = (rc < 0 ? rc : -EINVAL); 763 764 return rc; 765 } 766 767 static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf) 768 { 769 int err; 770 771 if (dev->have_langid) 772 return 0; 773 774 if (dev->string_langid < 0) 775 return -EPIPE; 776 777 err = usb_string_sub(dev, 0, 0, tbuf); 778 779 /* If the string was reported but is malformed, default to english 780 * (0x0409) */ 781 if (err == -ENODATA || (err > 0 && err < 4)) { 782 dev->string_langid = 0x0409; 783 dev->have_langid = 1; 784 dev_err(&dev->dev, 785 "language id specifier not provided by device, defaulting to English\n"); 786 return 0; 787 } 788 789 /* In case of all other errors, we assume the device is not able to 790 * deal with strings at all. Set string_langid to -1 in order to 791 * prevent any string to be retrieved from the device */ 792 if (err < 0) { 793 dev_info(&dev->dev, "string descriptor 0 read error: %d\n", 794 err); 795 dev->string_langid = -1; 796 return -EPIPE; 797 } 798 799 /* always use the first langid listed */ 800 dev->string_langid = tbuf[2] | (tbuf[3] << 8); 801 dev->have_langid = 1; 802 dev_dbg(&dev->dev, "default language 0x%04x\n", 803 dev->string_langid); 804 return 0; 805 } 806 807 /** 808 * usb_string - returns UTF-8 version of a string descriptor 809 * @dev: the device whose string descriptor is being retrieved 810 * @index: the number of the descriptor 811 * @buf: where to put the string 812 * @size: how big is "buf"? 813 * Context: !in_interrupt () 814 * 815 * This converts the UTF-16LE encoded strings returned by devices, from 816 * usb_get_string_descriptor(), to null-terminated UTF-8 encoded ones 817 * that are more usable in most kernel contexts. Note that this function 818 * chooses strings in the first language supported by the device. 819 * 820 * This call is synchronous, and may not be used in an interrupt context. 821 * 822 * Return: length of the string (>= 0) or usb_control_msg status (< 0). 823 */ 824 int usb_string(struct usb_device *dev, int index, char *buf, size_t size) 825 { 826 unsigned char *tbuf; 827 int err; 828 829 if (dev->state == USB_STATE_SUSPENDED) 830 return -EHOSTUNREACH; 831 if (size <= 0 || !buf) 832 return -EINVAL; 833 buf[0] = 0; 834 if (index <= 0 || index >= 256) 835 return -EINVAL; 836 tbuf = kmalloc(256, GFP_NOIO); 837 if (!tbuf) 838 return -ENOMEM; 839 840 err = usb_get_langid(dev, tbuf); 841 if (err < 0) 842 goto errout; 843 844 err = usb_string_sub(dev, dev->string_langid, index, tbuf); 845 if (err < 0) 846 goto errout; 847 848 size--; /* leave room for trailing NULL char in output buffer */ 849 err = utf16s_to_utf8s((wchar_t *) &tbuf[2], (err - 2) / 2, 850 UTF16_LITTLE_ENDIAN, buf, size); 851 buf[err] = 0; 852 853 if (tbuf[1] != USB_DT_STRING) 854 dev_dbg(&dev->dev, 855 "wrong descriptor type %02x for string %d (\"%s\")\n", 856 tbuf[1], index, buf); 857 858 errout: 859 kfree(tbuf); 860 return err; 861 } 862 EXPORT_SYMBOL_GPL(usb_string); 863 864 /* one UTF-8-encoded 16-bit character has at most three bytes */ 865 #define MAX_USB_STRING_SIZE (127 * 3 + 1) 866 867 /** 868 * usb_cache_string - read a string descriptor and cache it for later use 869 * @udev: the device whose string descriptor is being read 870 * @index: the descriptor index 871 * 872 * Return: A pointer to a kmalloc'ed buffer containing the descriptor string, 873 * or %NULL if the index is 0 or the string could not be read. 874 */ 875 char *usb_cache_string(struct usb_device *udev, int index) 876 { 877 char *buf; 878 char *smallbuf = NULL; 879 int len; 880 881 if (index <= 0) 882 return NULL; 883 884 buf = kmalloc(MAX_USB_STRING_SIZE, GFP_NOIO); 885 if (buf) { 886 len = usb_string(udev, index, buf, MAX_USB_STRING_SIZE); 887 if (len > 0) { 888 smallbuf = kmalloc(++len, GFP_NOIO); 889 if (!smallbuf) 890 return buf; 891 memcpy(smallbuf, buf, len); 892 } 893 kfree(buf); 894 } 895 return smallbuf; 896 } 897 898 /* 899 * usb_get_device_descriptor - (re)reads the device descriptor (usbcore) 900 * @dev: the device whose device descriptor is being updated 901 * @size: how much of the descriptor to read 902 * Context: !in_interrupt () 903 * 904 * Updates the copy of the device descriptor stored in the device structure, 905 * which dedicates space for this purpose. 906 * 907 * Not exported, only for use by the core. If drivers really want to read 908 * the device descriptor directly, they can call usb_get_descriptor() with 909 * type = USB_DT_DEVICE and index = 0. 910 * 911 * This call is synchronous, and may not be used in an interrupt context. 912 * 913 * Return: The number of bytes received on success, or else the status code 914 * returned by the underlying usb_control_msg() call. 915 */ 916 int usb_get_device_descriptor(struct usb_device *dev, unsigned int size) 917 { 918 struct usb_device_descriptor *desc; 919 int ret; 920 921 if (size > sizeof(*desc)) 922 return -EINVAL; 923 desc = kmalloc(sizeof(*desc), GFP_NOIO); 924 if (!desc) 925 return -ENOMEM; 926 927 ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size); 928 if (ret >= 0) 929 memcpy(&dev->descriptor, desc, size); 930 kfree(desc); 931 return ret; 932 } 933 934 /* 935 * usb_set_isoch_delay - informs the device of the packet transmit delay 936 * @dev: the device whose delay is to be informed 937 * Context: !in_interrupt() 938 * 939 * Since this is an optional request, we don't bother if it fails. 940 */ 941 int usb_set_isoch_delay(struct usb_device *dev) 942 { 943 /* skip hub devices */ 944 if (dev->descriptor.bDeviceClass == USB_CLASS_HUB) 945 return 0; 946 947 /* skip non-SS/non-SSP devices */ 948 if (dev->speed < USB_SPEED_SUPER) 949 return 0; 950 951 return usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 952 USB_REQ_SET_ISOCH_DELAY, 953 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, 954 dev->hub_delay, 0, NULL, 0, 955 USB_CTRL_SET_TIMEOUT); 956 } 957 958 /** 959 * usb_get_status - issues a GET_STATUS call 960 * @dev: the device whose status is being checked 961 * @recip: USB_RECIP_*; for device, interface, or endpoint 962 * @type: USB_STATUS_TYPE_*; for standard or PTM status types 963 * @target: zero (for device), else interface or endpoint number 964 * @data: pointer to two bytes of bitmap data 965 * Context: !in_interrupt () 966 * 967 * Returns device, interface, or endpoint status. Normally only of 968 * interest to see if the device is self powered, or has enabled the 969 * remote wakeup facility; or whether a bulk or interrupt endpoint 970 * is halted ("stalled"). 971 * 972 * Bits in these status bitmaps are set using the SET_FEATURE request, 973 * and cleared using the CLEAR_FEATURE request. The usb_clear_halt() 974 * function should be used to clear halt ("stall") status. 975 * 976 * This call is synchronous, and may not be used in an interrupt context. 977 * 978 * Returns 0 and the status value in *@data (in host byte order) on success, 979 * or else the status code from the underlying usb_control_msg() call. 980 */ 981 int usb_get_status(struct usb_device *dev, int recip, int type, int target, 982 void *data) 983 { 984 int ret; 985 void *status; 986 int length; 987 988 switch (type) { 989 case USB_STATUS_TYPE_STANDARD: 990 length = 2; 991 break; 992 case USB_STATUS_TYPE_PTM: 993 if (recip != USB_RECIP_DEVICE) 994 return -EINVAL; 995 996 length = 4; 997 break; 998 default: 999 return -EINVAL; 1000 } 1001 1002 status = kmalloc(length, GFP_KERNEL); 1003 if (!status) 1004 return -ENOMEM; 1005 1006 ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), 1007 USB_REQ_GET_STATUS, USB_DIR_IN | recip, USB_STATUS_TYPE_STANDARD, 1008 target, status, length, USB_CTRL_GET_TIMEOUT); 1009 1010 switch (ret) { 1011 case 4: 1012 if (type != USB_STATUS_TYPE_PTM) { 1013 ret = -EIO; 1014 break; 1015 } 1016 1017 *(u32 *) data = le32_to_cpu(*(__le32 *) status); 1018 ret = 0; 1019 break; 1020 case 2: 1021 if (type != USB_STATUS_TYPE_STANDARD) { 1022 ret = -EIO; 1023 break; 1024 } 1025 1026 *(u16 *) data = le16_to_cpu(*(__le16 *) status); 1027 ret = 0; 1028 break; 1029 default: 1030 ret = -EIO; 1031 } 1032 1033 kfree(status); 1034 return ret; 1035 } 1036 EXPORT_SYMBOL_GPL(usb_get_status); 1037 1038 /** 1039 * usb_clear_halt - tells device to clear endpoint halt/stall condition 1040 * @dev: device whose endpoint is halted 1041 * @pipe: endpoint "pipe" being cleared 1042 * Context: !in_interrupt () 1043 * 1044 * This is used to clear halt conditions for bulk and interrupt endpoints, 1045 * as reported by URB completion status. Endpoints that are halted are 1046 * sometimes referred to as being "stalled". Such endpoints are unable 1047 * to transmit or receive data until the halt status is cleared. Any URBs 1048 * queued for such an endpoint should normally be unlinked by the driver 1049 * before clearing the halt condition, as described in sections 5.7.5 1050 * and 5.8.5 of the USB 2.0 spec. 1051 * 1052 * Note that control and isochronous endpoints don't halt, although control 1053 * endpoints report "protocol stall" (for unsupported requests) using the 1054 * same status code used to report a true stall. 1055 * 1056 * This call is synchronous, and may not be used in an interrupt context. 1057 * 1058 * Return: Zero on success, or else the status code returned by the 1059 * underlying usb_control_msg() call. 1060 */ 1061 int usb_clear_halt(struct usb_device *dev, int pipe) 1062 { 1063 int result; 1064 int endp = usb_pipeendpoint(pipe); 1065 1066 if (usb_pipein(pipe)) 1067 endp |= USB_DIR_IN; 1068 1069 /* we don't care if it wasn't halted first. in fact some devices 1070 * (like some ibmcam model 1 units) seem to expect hosts to make 1071 * this request for iso endpoints, which can't halt! 1072 */ 1073 result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1074 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 1075 USB_ENDPOINT_HALT, endp, NULL, 0, 1076 USB_CTRL_SET_TIMEOUT); 1077 1078 /* don't un-halt or force to DATA0 except on success */ 1079 if (result < 0) 1080 return result; 1081 1082 /* NOTE: seems like Microsoft and Apple don't bother verifying 1083 * the clear "took", so some devices could lock up if you check... 1084 * such as the Hagiwara FlashGate DUAL. So we won't bother. 1085 * 1086 * NOTE: make sure the logic here doesn't diverge much from 1087 * the copy in usb-storage, for as long as we need two copies. 1088 */ 1089 1090 usb_reset_endpoint(dev, endp); 1091 1092 return 0; 1093 } 1094 EXPORT_SYMBOL_GPL(usb_clear_halt); 1095 1096 static int create_intf_ep_devs(struct usb_interface *intf) 1097 { 1098 struct usb_device *udev = interface_to_usbdev(intf); 1099 struct usb_host_interface *alt = intf->cur_altsetting; 1100 int i; 1101 1102 if (intf->ep_devs_created || intf->unregistering) 1103 return 0; 1104 1105 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1106 (void) usb_create_ep_devs(&intf->dev, &alt->endpoint[i], udev); 1107 intf->ep_devs_created = 1; 1108 return 0; 1109 } 1110 1111 static void remove_intf_ep_devs(struct usb_interface *intf) 1112 { 1113 struct usb_host_interface *alt = intf->cur_altsetting; 1114 int i; 1115 1116 if (!intf->ep_devs_created) 1117 return; 1118 1119 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1120 usb_remove_ep_devs(&alt->endpoint[i]); 1121 intf->ep_devs_created = 0; 1122 } 1123 1124 /** 1125 * usb_disable_endpoint -- Disable an endpoint by address 1126 * @dev: the device whose endpoint is being disabled 1127 * @epaddr: the endpoint's address. Endpoint number for output, 1128 * endpoint number + USB_DIR_IN for input 1129 * @reset_hardware: flag to erase any endpoint state stored in the 1130 * controller hardware 1131 * 1132 * Disables the endpoint for URB submission and nukes all pending URBs. 1133 * If @reset_hardware is set then also deallocates hcd/hardware state 1134 * for the endpoint. 1135 */ 1136 void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr, 1137 bool reset_hardware) 1138 { 1139 unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; 1140 struct usb_host_endpoint *ep; 1141 1142 if (!dev) 1143 return; 1144 1145 if (usb_endpoint_out(epaddr)) { 1146 ep = dev->ep_out[epnum]; 1147 if (reset_hardware && epnum != 0) 1148 dev->ep_out[epnum] = NULL; 1149 } else { 1150 ep = dev->ep_in[epnum]; 1151 if (reset_hardware && epnum != 0) 1152 dev->ep_in[epnum] = NULL; 1153 } 1154 if (ep) { 1155 ep->enabled = 0; 1156 usb_hcd_flush_endpoint(dev, ep); 1157 if (reset_hardware) 1158 usb_hcd_disable_endpoint(dev, ep); 1159 } 1160 } 1161 1162 /** 1163 * usb_reset_endpoint - Reset an endpoint's state. 1164 * @dev: the device whose endpoint is to be reset 1165 * @epaddr: the endpoint's address. Endpoint number for output, 1166 * endpoint number + USB_DIR_IN for input 1167 * 1168 * Resets any host-side endpoint state such as the toggle bit, 1169 * sequence number or current window. 1170 */ 1171 void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr) 1172 { 1173 unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; 1174 struct usb_host_endpoint *ep; 1175 1176 if (usb_endpoint_out(epaddr)) 1177 ep = dev->ep_out[epnum]; 1178 else 1179 ep = dev->ep_in[epnum]; 1180 if (ep) 1181 usb_hcd_reset_endpoint(dev, ep); 1182 } 1183 EXPORT_SYMBOL_GPL(usb_reset_endpoint); 1184 1185 1186 /** 1187 * usb_disable_interface -- Disable all endpoints for an interface 1188 * @dev: the device whose interface is being disabled 1189 * @intf: pointer to the interface descriptor 1190 * @reset_hardware: flag to erase any endpoint state stored in the 1191 * controller hardware 1192 * 1193 * Disables all the endpoints for the interface's current altsetting. 1194 */ 1195 void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf, 1196 bool reset_hardware) 1197 { 1198 struct usb_host_interface *alt = intf->cur_altsetting; 1199 int i; 1200 1201 for (i = 0; i < alt->desc.bNumEndpoints; ++i) { 1202 usb_disable_endpoint(dev, 1203 alt->endpoint[i].desc.bEndpointAddress, 1204 reset_hardware); 1205 } 1206 } 1207 1208 /* 1209 * usb_disable_device_endpoints -- Disable all endpoints for a device 1210 * @dev: the device whose endpoints are being disabled 1211 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. 1212 */ 1213 static void usb_disable_device_endpoints(struct usb_device *dev, int skip_ep0) 1214 { 1215 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1216 int i; 1217 1218 if (hcd->driver->check_bandwidth) { 1219 /* First pass: Cancel URBs, leave endpoint pointers intact. */ 1220 for (i = skip_ep0; i < 16; ++i) { 1221 usb_disable_endpoint(dev, i, false); 1222 usb_disable_endpoint(dev, i + USB_DIR_IN, false); 1223 } 1224 /* Remove endpoints from the host controller internal state */ 1225 mutex_lock(hcd->bandwidth_mutex); 1226 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1227 mutex_unlock(hcd->bandwidth_mutex); 1228 } 1229 /* Second pass: remove endpoint pointers */ 1230 for (i = skip_ep0; i < 16; ++i) { 1231 usb_disable_endpoint(dev, i, true); 1232 usb_disable_endpoint(dev, i + USB_DIR_IN, true); 1233 } 1234 } 1235 1236 /** 1237 * usb_disable_device - Disable all the endpoints for a USB device 1238 * @dev: the device whose endpoints are being disabled 1239 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. 1240 * 1241 * Disables all the device's endpoints, potentially including endpoint 0. 1242 * Deallocates hcd/hardware state for the endpoints (nuking all or most 1243 * pending urbs) and usbcore state for the interfaces, so that usbcore 1244 * must usb_set_configuration() before any interfaces could be used. 1245 */ 1246 void usb_disable_device(struct usb_device *dev, int skip_ep0) 1247 { 1248 int i; 1249 1250 /* getting rid of interfaces will disconnect 1251 * any drivers bound to them (a key side effect) 1252 */ 1253 if (dev->actconfig) { 1254 /* 1255 * FIXME: In order to avoid self-deadlock involving the 1256 * bandwidth_mutex, we have to mark all the interfaces 1257 * before unregistering any of them. 1258 */ 1259 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) 1260 dev->actconfig->interface[i]->unregistering = 1; 1261 1262 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1263 struct usb_interface *interface; 1264 1265 /* remove this interface if it has been registered */ 1266 interface = dev->actconfig->interface[i]; 1267 if (!device_is_registered(&interface->dev)) 1268 continue; 1269 dev_dbg(&dev->dev, "unregistering interface %s\n", 1270 dev_name(&interface->dev)); 1271 remove_intf_ep_devs(interface); 1272 device_del(&interface->dev); 1273 } 1274 1275 /* Now that the interfaces are unbound, nobody should 1276 * try to access them. 1277 */ 1278 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1279 put_device(&dev->actconfig->interface[i]->dev); 1280 dev->actconfig->interface[i] = NULL; 1281 } 1282 1283 usb_disable_usb2_hardware_lpm(dev); 1284 usb_unlocked_disable_lpm(dev); 1285 usb_disable_ltm(dev); 1286 1287 dev->actconfig = NULL; 1288 if (dev->state == USB_STATE_CONFIGURED) 1289 usb_set_device_state(dev, USB_STATE_ADDRESS); 1290 } 1291 1292 dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__, 1293 skip_ep0 ? "non-ep0" : "all"); 1294 1295 usb_disable_device_endpoints(dev, skip_ep0); 1296 } 1297 1298 /** 1299 * usb_enable_endpoint - Enable an endpoint for USB communications 1300 * @dev: the device whose interface is being enabled 1301 * @ep: the endpoint 1302 * @reset_ep: flag to reset the endpoint state 1303 * 1304 * Resets the endpoint state if asked, and sets dev->ep_{in,out} pointers. 1305 * For control endpoints, both the input and output sides are handled. 1306 */ 1307 void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep, 1308 bool reset_ep) 1309 { 1310 int epnum = usb_endpoint_num(&ep->desc); 1311 int is_out = usb_endpoint_dir_out(&ep->desc); 1312 int is_control = usb_endpoint_xfer_control(&ep->desc); 1313 1314 if (reset_ep) 1315 usb_hcd_reset_endpoint(dev, ep); 1316 if (is_out || is_control) 1317 dev->ep_out[epnum] = ep; 1318 if (!is_out || is_control) 1319 dev->ep_in[epnum] = ep; 1320 ep->enabled = 1; 1321 } 1322 1323 /** 1324 * usb_enable_interface - Enable all the endpoints for an interface 1325 * @dev: the device whose interface is being enabled 1326 * @intf: pointer to the interface descriptor 1327 * @reset_eps: flag to reset the endpoints' state 1328 * 1329 * Enables all the endpoints for the interface's current altsetting. 1330 */ 1331 void usb_enable_interface(struct usb_device *dev, 1332 struct usb_interface *intf, bool reset_eps) 1333 { 1334 struct usb_host_interface *alt = intf->cur_altsetting; 1335 int i; 1336 1337 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1338 usb_enable_endpoint(dev, &alt->endpoint[i], reset_eps); 1339 } 1340 1341 /** 1342 * usb_set_interface - Makes a particular alternate setting be current 1343 * @dev: the device whose interface is being updated 1344 * @interface: the interface being updated 1345 * @alternate: the setting being chosen. 1346 * Context: !in_interrupt () 1347 * 1348 * This is used to enable data transfers on interfaces that may not 1349 * be enabled by default. Not all devices support such configurability. 1350 * Only the driver bound to an interface may change its setting. 1351 * 1352 * Within any given configuration, each interface may have several 1353 * alternative settings. These are often used to control levels of 1354 * bandwidth consumption. For example, the default setting for a high 1355 * speed interrupt endpoint may not send more than 64 bytes per microframe, 1356 * while interrupt transfers of up to 3KBytes per microframe are legal. 1357 * Also, isochronous endpoints may never be part of an 1358 * interface's default setting. To access such bandwidth, alternate 1359 * interface settings must be made current. 1360 * 1361 * Note that in the Linux USB subsystem, bandwidth associated with 1362 * an endpoint in a given alternate setting is not reserved until an URB 1363 * is submitted that needs that bandwidth. Some other operating systems 1364 * allocate bandwidth early, when a configuration is chosen. 1365 * 1366 * xHCI reserves bandwidth and configures the alternate setting in 1367 * usb_hcd_alloc_bandwidth(). If it fails the original interface altsetting 1368 * may be disabled. Drivers cannot rely on any particular alternate 1369 * setting being in effect after a failure. 1370 * 1371 * This call is synchronous, and may not be used in an interrupt context. 1372 * Also, drivers must not change altsettings while urbs are scheduled for 1373 * endpoints in that interface; all such urbs must first be completed 1374 * (perhaps forced by unlinking). 1375 * 1376 * Return: Zero on success, or else the status code returned by the 1377 * underlying usb_control_msg() call. 1378 */ 1379 int usb_set_interface(struct usb_device *dev, int interface, int alternate) 1380 { 1381 struct usb_interface *iface; 1382 struct usb_host_interface *alt; 1383 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1384 int i, ret, manual = 0; 1385 unsigned int epaddr; 1386 unsigned int pipe; 1387 1388 if (dev->state == USB_STATE_SUSPENDED) 1389 return -EHOSTUNREACH; 1390 1391 iface = usb_ifnum_to_if(dev, interface); 1392 if (!iface) { 1393 dev_dbg(&dev->dev, "selecting invalid interface %d\n", 1394 interface); 1395 return -EINVAL; 1396 } 1397 if (iface->unregistering) 1398 return -ENODEV; 1399 1400 alt = usb_altnum_to_altsetting(iface, alternate); 1401 if (!alt) { 1402 dev_warn(&dev->dev, "selecting invalid altsetting %d\n", 1403 alternate); 1404 return -EINVAL; 1405 } 1406 /* 1407 * usb3 hosts configure the interface in usb_hcd_alloc_bandwidth, 1408 * including freeing dropped endpoint ring buffers. 1409 * Make sure the interface endpoints are flushed before that 1410 */ 1411 usb_disable_interface(dev, iface, false); 1412 1413 /* Make sure we have enough bandwidth for this alternate interface. 1414 * Remove the current alt setting and add the new alt setting. 1415 */ 1416 mutex_lock(hcd->bandwidth_mutex); 1417 /* Disable LPM, and re-enable it once the new alt setting is installed, 1418 * so that the xHCI driver can recalculate the U1/U2 timeouts. 1419 */ 1420 if (usb_disable_lpm(dev)) { 1421 dev_err(&iface->dev, "%s Failed to disable LPM\n", __func__); 1422 mutex_unlock(hcd->bandwidth_mutex); 1423 return -ENOMEM; 1424 } 1425 /* Changing alt-setting also frees any allocated streams */ 1426 for (i = 0; i < iface->cur_altsetting->desc.bNumEndpoints; i++) 1427 iface->cur_altsetting->endpoint[i].streams = 0; 1428 1429 ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt); 1430 if (ret < 0) { 1431 dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n", 1432 alternate); 1433 usb_enable_lpm(dev); 1434 mutex_unlock(hcd->bandwidth_mutex); 1435 return ret; 1436 } 1437 1438 if (dev->quirks & USB_QUIRK_NO_SET_INTF) 1439 ret = -EPIPE; 1440 else 1441 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1442 USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE, 1443 alternate, interface, NULL, 0, 5000); 1444 1445 /* 9.4.10 says devices don't need this and are free to STALL the 1446 * request if the interface only has one alternate setting. 1447 */ 1448 if (ret == -EPIPE && iface->num_altsetting == 1) { 1449 dev_dbg(&dev->dev, 1450 "manual set_interface for iface %d, alt %d\n", 1451 interface, alternate); 1452 manual = 1; 1453 } else if (ret < 0) { 1454 /* Re-instate the old alt setting */ 1455 usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting); 1456 usb_enable_lpm(dev); 1457 mutex_unlock(hcd->bandwidth_mutex); 1458 return ret; 1459 } 1460 mutex_unlock(hcd->bandwidth_mutex); 1461 1462 /* FIXME drivers shouldn't need to replicate/bugfix the logic here 1463 * when they implement async or easily-killable versions of this or 1464 * other "should-be-internal" functions (like clear_halt). 1465 * should hcd+usbcore postprocess control requests? 1466 */ 1467 1468 /* prevent submissions using previous endpoint settings */ 1469 if (iface->cur_altsetting != alt) { 1470 remove_intf_ep_devs(iface); 1471 usb_remove_sysfs_intf_files(iface); 1472 } 1473 usb_disable_interface(dev, iface, true); 1474 1475 iface->cur_altsetting = alt; 1476 1477 /* Now that the interface is installed, re-enable LPM. */ 1478 usb_unlocked_enable_lpm(dev); 1479 1480 /* If the interface only has one altsetting and the device didn't 1481 * accept the request, we attempt to carry out the equivalent action 1482 * by manually clearing the HALT feature for each endpoint in the 1483 * new altsetting. 1484 */ 1485 if (manual) { 1486 for (i = 0; i < alt->desc.bNumEndpoints; i++) { 1487 epaddr = alt->endpoint[i].desc.bEndpointAddress; 1488 pipe = __create_pipe(dev, 1489 USB_ENDPOINT_NUMBER_MASK & epaddr) | 1490 (usb_endpoint_out(epaddr) ? 1491 USB_DIR_OUT : USB_DIR_IN); 1492 1493 usb_clear_halt(dev, pipe); 1494 } 1495 } 1496 1497 /* 9.1.1.5: reset toggles for all endpoints in the new altsetting 1498 * 1499 * Note: 1500 * Despite EP0 is always present in all interfaces/AS, the list of 1501 * endpoints from the descriptor does not contain EP0. Due to its 1502 * omnipresence one might expect EP0 being considered "affected" by 1503 * any SetInterface request and hence assume toggles need to be reset. 1504 * However, EP0 toggles are re-synced for every individual transfer 1505 * during the SETUP stage - hence EP0 toggles are "don't care" here. 1506 * (Likewise, EP0 never "halts" on well designed devices.) 1507 */ 1508 usb_enable_interface(dev, iface, true); 1509 if (device_is_registered(&iface->dev)) { 1510 usb_create_sysfs_intf_files(iface); 1511 create_intf_ep_devs(iface); 1512 } 1513 return 0; 1514 } 1515 EXPORT_SYMBOL_GPL(usb_set_interface); 1516 1517 /** 1518 * usb_reset_configuration - lightweight device reset 1519 * @dev: the device whose configuration is being reset 1520 * 1521 * This issues a standard SET_CONFIGURATION request to the device using 1522 * the current configuration. The effect is to reset most USB-related 1523 * state in the device, including interface altsettings (reset to zero), 1524 * endpoint halts (cleared), and endpoint state (only for bulk and interrupt 1525 * endpoints). Other usbcore state is unchanged, including bindings of 1526 * usb device drivers to interfaces. 1527 * 1528 * Because this affects multiple interfaces, avoid using this with composite 1529 * (multi-interface) devices. Instead, the driver for each interface may 1530 * use usb_set_interface() on the interfaces it claims. Be careful though; 1531 * some devices don't support the SET_INTERFACE request, and others won't 1532 * reset all the interface state (notably endpoint state). Resetting the whole 1533 * configuration would affect other drivers' interfaces. 1534 * 1535 * The caller must own the device lock. 1536 * 1537 * Return: Zero on success, else a negative error code. 1538 * 1539 * If this routine fails the device will probably be in an unusable state 1540 * with endpoints disabled, and interfaces only partially enabled. 1541 */ 1542 int usb_reset_configuration(struct usb_device *dev) 1543 { 1544 int i, retval; 1545 struct usb_host_config *config; 1546 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1547 1548 if (dev->state == USB_STATE_SUSPENDED) 1549 return -EHOSTUNREACH; 1550 1551 /* caller must have locked the device and must own 1552 * the usb bus readlock (so driver bindings are stable); 1553 * calls during probe() are fine 1554 */ 1555 1556 usb_disable_device_endpoints(dev, 1); /* skip ep0*/ 1557 1558 config = dev->actconfig; 1559 retval = 0; 1560 mutex_lock(hcd->bandwidth_mutex); 1561 /* Disable LPM, and re-enable it once the configuration is reset, so 1562 * that the xHCI driver can recalculate the U1/U2 timeouts. 1563 */ 1564 if (usb_disable_lpm(dev)) { 1565 dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); 1566 mutex_unlock(hcd->bandwidth_mutex); 1567 return -ENOMEM; 1568 } 1569 1570 /* xHCI adds all endpoints in usb_hcd_alloc_bandwidth */ 1571 retval = usb_hcd_alloc_bandwidth(dev, config, NULL, NULL); 1572 if (retval < 0) { 1573 usb_enable_lpm(dev); 1574 mutex_unlock(hcd->bandwidth_mutex); 1575 return retval; 1576 } 1577 retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1578 USB_REQ_SET_CONFIGURATION, 0, 1579 config->desc.bConfigurationValue, 0, 1580 NULL, 0, USB_CTRL_SET_TIMEOUT); 1581 if (retval < 0) { 1582 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1583 usb_enable_lpm(dev); 1584 mutex_unlock(hcd->bandwidth_mutex); 1585 return retval; 1586 } 1587 mutex_unlock(hcd->bandwidth_mutex); 1588 1589 /* re-init hc/hcd interface/endpoint state */ 1590 for (i = 0; i < config->desc.bNumInterfaces; i++) { 1591 struct usb_interface *intf = config->interface[i]; 1592 struct usb_host_interface *alt; 1593 1594 alt = usb_altnum_to_altsetting(intf, 0); 1595 1596 /* No altsetting 0? We'll assume the first altsetting. 1597 * We could use a GetInterface call, but if a device is 1598 * so non-compliant that it doesn't have altsetting 0 1599 * then I wouldn't trust its reply anyway. 1600 */ 1601 if (!alt) 1602 alt = &intf->altsetting[0]; 1603 1604 if (alt != intf->cur_altsetting) { 1605 remove_intf_ep_devs(intf); 1606 usb_remove_sysfs_intf_files(intf); 1607 } 1608 intf->cur_altsetting = alt; 1609 usb_enable_interface(dev, intf, true); 1610 if (device_is_registered(&intf->dev)) { 1611 usb_create_sysfs_intf_files(intf); 1612 create_intf_ep_devs(intf); 1613 } 1614 } 1615 /* Now that the interfaces are installed, re-enable LPM. */ 1616 usb_unlocked_enable_lpm(dev); 1617 return 0; 1618 } 1619 EXPORT_SYMBOL_GPL(usb_reset_configuration); 1620 1621 static void usb_release_interface(struct device *dev) 1622 { 1623 struct usb_interface *intf = to_usb_interface(dev); 1624 struct usb_interface_cache *intfc = 1625 altsetting_to_usb_interface_cache(intf->altsetting); 1626 1627 kref_put(&intfc->ref, usb_release_interface_cache); 1628 usb_put_dev(interface_to_usbdev(intf)); 1629 of_node_put(dev->of_node); 1630 kfree(intf); 1631 } 1632 1633 /* 1634 * usb_deauthorize_interface - deauthorize an USB interface 1635 * 1636 * @intf: USB interface structure 1637 */ 1638 void usb_deauthorize_interface(struct usb_interface *intf) 1639 { 1640 struct device *dev = &intf->dev; 1641 1642 device_lock(dev->parent); 1643 1644 if (intf->authorized) { 1645 device_lock(dev); 1646 intf->authorized = 0; 1647 device_unlock(dev); 1648 1649 usb_forced_unbind_intf(intf); 1650 } 1651 1652 device_unlock(dev->parent); 1653 } 1654 1655 /* 1656 * usb_authorize_interface - authorize an USB interface 1657 * 1658 * @intf: USB interface structure 1659 */ 1660 void usb_authorize_interface(struct usb_interface *intf) 1661 { 1662 struct device *dev = &intf->dev; 1663 1664 if (!intf->authorized) { 1665 device_lock(dev); 1666 intf->authorized = 1; /* authorize interface */ 1667 device_unlock(dev); 1668 } 1669 } 1670 1671 static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env) 1672 { 1673 struct usb_device *usb_dev; 1674 struct usb_interface *intf; 1675 struct usb_host_interface *alt; 1676 1677 intf = to_usb_interface(dev); 1678 usb_dev = interface_to_usbdev(intf); 1679 alt = intf->cur_altsetting; 1680 1681 if (add_uevent_var(env, "INTERFACE=%d/%d/%d", 1682 alt->desc.bInterfaceClass, 1683 alt->desc.bInterfaceSubClass, 1684 alt->desc.bInterfaceProtocol)) 1685 return -ENOMEM; 1686 1687 if (add_uevent_var(env, 1688 "MODALIAS=usb:" 1689 "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02Xin%02X", 1690 le16_to_cpu(usb_dev->descriptor.idVendor), 1691 le16_to_cpu(usb_dev->descriptor.idProduct), 1692 le16_to_cpu(usb_dev->descriptor.bcdDevice), 1693 usb_dev->descriptor.bDeviceClass, 1694 usb_dev->descriptor.bDeviceSubClass, 1695 usb_dev->descriptor.bDeviceProtocol, 1696 alt->desc.bInterfaceClass, 1697 alt->desc.bInterfaceSubClass, 1698 alt->desc.bInterfaceProtocol, 1699 alt->desc.bInterfaceNumber)) 1700 return -ENOMEM; 1701 1702 return 0; 1703 } 1704 1705 struct device_type usb_if_device_type = { 1706 .name = "usb_interface", 1707 .release = usb_release_interface, 1708 .uevent = usb_if_uevent, 1709 }; 1710 1711 static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev, 1712 struct usb_host_config *config, 1713 u8 inum) 1714 { 1715 struct usb_interface_assoc_descriptor *retval = NULL; 1716 struct usb_interface_assoc_descriptor *intf_assoc; 1717 int first_intf; 1718 int last_intf; 1719 int i; 1720 1721 for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) { 1722 intf_assoc = config->intf_assoc[i]; 1723 if (intf_assoc->bInterfaceCount == 0) 1724 continue; 1725 1726 first_intf = intf_assoc->bFirstInterface; 1727 last_intf = first_intf + (intf_assoc->bInterfaceCount - 1); 1728 if (inum >= first_intf && inum <= last_intf) { 1729 if (!retval) 1730 retval = intf_assoc; 1731 else 1732 dev_err(&dev->dev, "Interface #%d referenced" 1733 " by multiple IADs\n", inum); 1734 } 1735 } 1736 1737 return retval; 1738 } 1739 1740 1741 /* 1742 * Internal function to queue a device reset 1743 * See usb_queue_reset_device() for more details 1744 */ 1745 static void __usb_queue_reset_device(struct work_struct *ws) 1746 { 1747 int rc; 1748 struct usb_interface *iface = 1749 container_of(ws, struct usb_interface, reset_ws); 1750 struct usb_device *udev = interface_to_usbdev(iface); 1751 1752 rc = usb_lock_device_for_reset(udev, iface); 1753 if (rc >= 0) { 1754 usb_reset_device(udev); 1755 usb_unlock_device(udev); 1756 } 1757 usb_put_intf(iface); /* Undo _get_ in usb_queue_reset_device() */ 1758 } 1759 1760 1761 /* 1762 * usb_set_configuration - Makes a particular device setting be current 1763 * @dev: the device whose configuration is being updated 1764 * @configuration: the configuration being chosen. 1765 * Context: !in_interrupt(), caller owns the device lock 1766 * 1767 * This is used to enable non-default device modes. Not all devices 1768 * use this kind of configurability; many devices only have one 1769 * configuration. 1770 * 1771 * @configuration is the value of the configuration to be installed. 1772 * According to the USB spec (e.g. section 9.1.1.5), configuration values 1773 * must be non-zero; a value of zero indicates that the device in 1774 * unconfigured. However some devices erroneously use 0 as one of their 1775 * configuration values. To help manage such devices, this routine will 1776 * accept @configuration = -1 as indicating the device should be put in 1777 * an unconfigured state. 1778 * 1779 * USB device configurations may affect Linux interoperability, 1780 * power consumption and the functionality available. For example, 1781 * the default configuration is limited to using 100mA of bus power, 1782 * so that when certain device functionality requires more power, 1783 * and the device is bus powered, that functionality should be in some 1784 * non-default device configuration. Other device modes may also be 1785 * reflected as configuration options, such as whether two ISDN 1786 * channels are available independently; and choosing between open 1787 * standard device protocols (like CDC) or proprietary ones. 1788 * 1789 * Note that a non-authorized device (dev->authorized == 0) will only 1790 * be put in unconfigured mode. 1791 * 1792 * Note that USB has an additional level of device configurability, 1793 * associated with interfaces. That configurability is accessed using 1794 * usb_set_interface(). 1795 * 1796 * This call is synchronous. The calling context must be able to sleep, 1797 * must own the device lock, and must not hold the driver model's USB 1798 * bus mutex; usb interface driver probe() methods cannot use this routine. 1799 * 1800 * Returns zero on success, or else the status code returned by the 1801 * underlying call that failed. On successful completion, each interface 1802 * in the original device configuration has been destroyed, and each one 1803 * in the new configuration has been probed by all relevant usb device 1804 * drivers currently known to the kernel. 1805 */ 1806 int usb_set_configuration(struct usb_device *dev, int configuration) 1807 { 1808 int i, ret; 1809 struct usb_host_config *cp = NULL; 1810 struct usb_interface **new_interfaces = NULL; 1811 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1812 int n, nintf; 1813 1814 if (dev->authorized == 0 || configuration == -1) 1815 configuration = 0; 1816 else { 1817 for (i = 0; i < dev->descriptor.bNumConfigurations; i++) { 1818 if (dev->config[i].desc.bConfigurationValue == 1819 configuration) { 1820 cp = &dev->config[i]; 1821 break; 1822 } 1823 } 1824 } 1825 if ((!cp && configuration != 0)) 1826 return -EINVAL; 1827 1828 /* The USB spec says configuration 0 means unconfigured. 1829 * But if a device includes a configuration numbered 0, 1830 * we will accept it as a correctly configured state. 1831 * Use -1 if you really want to unconfigure the device. 1832 */ 1833 if (cp && configuration == 0) 1834 dev_warn(&dev->dev, "config 0 descriptor??\n"); 1835 1836 /* Allocate memory for new interfaces before doing anything else, 1837 * so that if we run out then nothing will have changed. */ 1838 n = nintf = 0; 1839 if (cp) { 1840 nintf = cp->desc.bNumInterfaces; 1841 new_interfaces = kmalloc_array(nintf, sizeof(*new_interfaces), 1842 GFP_NOIO); 1843 if (!new_interfaces) 1844 return -ENOMEM; 1845 1846 for (; n < nintf; ++n) { 1847 new_interfaces[n] = kzalloc( 1848 sizeof(struct usb_interface), 1849 GFP_NOIO); 1850 if (!new_interfaces[n]) { 1851 ret = -ENOMEM; 1852 free_interfaces: 1853 while (--n >= 0) 1854 kfree(new_interfaces[n]); 1855 kfree(new_interfaces); 1856 return ret; 1857 } 1858 } 1859 1860 i = dev->bus_mA - usb_get_max_power(dev, cp); 1861 if (i < 0) 1862 dev_warn(&dev->dev, "new config #%d exceeds power " 1863 "limit by %dmA\n", 1864 configuration, -i); 1865 } 1866 1867 /* Wake up the device so we can send it the Set-Config request */ 1868 ret = usb_autoresume_device(dev); 1869 if (ret) 1870 goto free_interfaces; 1871 1872 /* if it's already configured, clear out old state first. 1873 * getting rid of old interfaces means unbinding their drivers. 1874 */ 1875 if (dev->state != USB_STATE_ADDRESS) 1876 usb_disable_device(dev, 1); /* Skip ep0 */ 1877 1878 /* Get rid of pending async Set-Config requests for this device */ 1879 cancel_async_set_config(dev); 1880 1881 /* Make sure we have bandwidth (and available HCD resources) for this 1882 * configuration. Remove endpoints from the schedule if we're dropping 1883 * this configuration to set configuration 0. After this point, the 1884 * host controller will not allow submissions to dropped endpoints. If 1885 * this call fails, the device state is unchanged. 1886 */ 1887 mutex_lock(hcd->bandwidth_mutex); 1888 /* Disable LPM, and re-enable it once the new configuration is 1889 * installed, so that the xHCI driver can recalculate the U1/U2 1890 * timeouts. 1891 */ 1892 if (dev->actconfig && usb_disable_lpm(dev)) { 1893 dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); 1894 mutex_unlock(hcd->bandwidth_mutex); 1895 ret = -ENOMEM; 1896 goto free_interfaces; 1897 } 1898 ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL); 1899 if (ret < 0) { 1900 if (dev->actconfig) 1901 usb_enable_lpm(dev); 1902 mutex_unlock(hcd->bandwidth_mutex); 1903 usb_autosuspend_device(dev); 1904 goto free_interfaces; 1905 } 1906 1907 /* 1908 * Initialize the new interface structures and the 1909 * hc/hcd/usbcore interface/endpoint state. 1910 */ 1911 for (i = 0; i < nintf; ++i) { 1912 struct usb_interface_cache *intfc; 1913 struct usb_interface *intf; 1914 struct usb_host_interface *alt; 1915 u8 ifnum; 1916 1917 cp->interface[i] = intf = new_interfaces[i]; 1918 intfc = cp->intf_cache[i]; 1919 intf->altsetting = intfc->altsetting; 1920 intf->num_altsetting = intfc->num_altsetting; 1921 intf->authorized = !!HCD_INTF_AUTHORIZED(hcd); 1922 kref_get(&intfc->ref); 1923 1924 alt = usb_altnum_to_altsetting(intf, 0); 1925 1926 /* No altsetting 0? We'll assume the first altsetting. 1927 * We could use a GetInterface call, but if a device is 1928 * so non-compliant that it doesn't have altsetting 0 1929 * then I wouldn't trust its reply anyway. 1930 */ 1931 if (!alt) 1932 alt = &intf->altsetting[0]; 1933 1934 ifnum = alt->desc.bInterfaceNumber; 1935 intf->intf_assoc = find_iad(dev, cp, ifnum); 1936 intf->cur_altsetting = alt; 1937 usb_enable_interface(dev, intf, true); 1938 intf->dev.parent = &dev->dev; 1939 if (usb_of_has_combined_node(dev)) { 1940 device_set_of_node_from_dev(&intf->dev, &dev->dev); 1941 } else { 1942 intf->dev.of_node = usb_of_get_interface_node(dev, 1943 configuration, ifnum); 1944 } 1945 ACPI_COMPANION_SET(&intf->dev, ACPI_COMPANION(&dev->dev)); 1946 intf->dev.driver = NULL; 1947 intf->dev.bus = &usb_bus_type; 1948 intf->dev.type = &usb_if_device_type; 1949 intf->dev.groups = usb_interface_groups; 1950 /* 1951 * Please refer to usb_alloc_dev() to see why we set 1952 * dma_mask and dma_pfn_offset. 1953 */ 1954 intf->dev.dma_mask = dev->dev.dma_mask; 1955 intf->dev.dma_pfn_offset = dev->dev.dma_pfn_offset; 1956 INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); 1957 intf->minor = -1; 1958 device_initialize(&intf->dev); 1959 pm_runtime_no_callbacks(&intf->dev); 1960 dev_set_name(&intf->dev, "%d-%s:%d.%d", dev->bus->busnum, 1961 dev->devpath, configuration, ifnum); 1962 usb_get_dev(dev); 1963 } 1964 kfree(new_interfaces); 1965 1966 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1967 USB_REQ_SET_CONFIGURATION, 0, configuration, 0, 1968 NULL, 0, USB_CTRL_SET_TIMEOUT); 1969 if (ret < 0 && cp) { 1970 /* 1971 * All the old state is gone, so what else can we do? 1972 * The device is probably useless now anyway. 1973 */ 1974 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1975 for (i = 0; i < nintf; ++i) { 1976 usb_disable_interface(dev, cp->interface[i], true); 1977 put_device(&cp->interface[i]->dev); 1978 cp->interface[i] = NULL; 1979 } 1980 cp = NULL; 1981 } 1982 1983 dev->actconfig = cp; 1984 mutex_unlock(hcd->bandwidth_mutex); 1985 1986 if (!cp) { 1987 usb_set_device_state(dev, USB_STATE_ADDRESS); 1988 1989 /* Leave LPM disabled while the device is unconfigured. */ 1990 usb_autosuspend_device(dev); 1991 return ret; 1992 } 1993 usb_set_device_state(dev, USB_STATE_CONFIGURED); 1994 1995 if (cp->string == NULL && 1996 !(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS)) 1997 cp->string = usb_cache_string(dev, cp->desc.iConfiguration); 1998 1999 /* Now that the interfaces are installed, re-enable LPM. */ 2000 usb_unlocked_enable_lpm(dev); 2001 /* Enable LTM if it was turned off by usb_disable_device. */ 2002 usb_enable_ltm(dev); 2003 2004 /* Now that all the interfaces are set up, register them 2005 * to trigger binding of drivers to interfaces. probe() 2006 * routines may install different altsettings and may 2007 * claim() any interfaces not yet bound. Many class drivers 2008 * need that: CDC, audio, video, etc. 2009 */ 2010 for (i = 0; i < nintf; ++i) { 2011 struct usb_interface *intf = cp->interface[i]; 2012 2013 if (intf->dev.of_node && 2014 !of_device_is_available(intf->dev.of_node)) { 2015 dev_info(&dev->dev, "skipping disabled interface %d\n", 2016 intf->cur_altsetting->desc.bInterfaceNumber); 2017 continue; 2018 } 2019 2020 dev_dbg(&dev->dev, 2021 "adding %s (config #%d, interface %d)\n", 2022 dev_name(&intf->dev), configuration, 2023 intf->cur_altsetting->desc.bInterfaceNumber); 2024 device_enable_async_suspend(&intf->dev); 2025 ret = device_add(&intf->dev); 2026 if (ret != 0) { 2027 dev_err(&dev->dev, "device_add(%s) --> %d\n", 2028 dev_name(&intf->dev), ret); 2029 continue; 2030 } 2031 create_intf_ep_devs(intf); 2032 } 2033 2034 usb_autosuspend_device(dev); 2035 return 0; 2036 } 2037 EXPORT_SYMBOL_GPL(usb_set_configuration); 2038 2039 static LIST_HEAD(set_config_list); 2040 static DEFINE_SPINLOCK(set_config_lock); 2041 2042 struct set_config_request { 2043 struct usb_device *udev; 2044 int config; 2045 struct work_struct work; 2046 struct list_head node; 2047 }; 2048 2049 /* Worker routine for usb_driver_set_configuration() */ 2050 static void driver_set_config_work(struct work_struct *work) 2051 { 2052 struct set_config_request *req = 2053 container_of(work, struct set_config_request, work); 2054 struct usb_device *udev = req->udev; 2055 2056 usb_lock_device(udev); 2057 spin_lock(&set_config_lock); 2058 list_del(&req->node); 2059 spin_unlock(&set_config_lock); 2060 2061 if (req->config >= -1) /* Is req still valid? */ 2062 usb_set_configuration(udev, req->config); 2063 usb_unlock_device(udev); 2064 usb_put_dev(udev); 2065 kfree(req); 2066 } 2067 2068 /* Cancel pending Set-Config requests for a device whose configuration 2069 * was just changed 2070 */ 2071 static void cancel_async_set_config(struct usb_device *udev) 2072 { 2073 struct set_config_request *req; 2074 2075 spin_lock(&set_config_lock); 2076 list_for_each_entry(req, &set_config_list, node) { 2077 if (req->udev == udev) 2078 req->config = -999; /* Mark as cancelled */ 2079 } 2080 spin_unlock(&set_config_lock); 2081 } 2082 2083 /** 2084 * usb_driver_set_configuration - Provide a way for drivers to change device configurations 2085 * @udev: the device whose configuration is being updated 2086 * @config: the configuration being chosen. 2087 * Context: In process context, must be able to sleep 2088 * 2089 * Device interface drivers are not allowed to change device configurations. 2090 * This is because changing configurations will destroy the interface the 2091 * driver is bound to and create new ones; it would be like a floppy-disk 2092 * driver telling the computer to replace the floppy-disk drive with a 2093 * tape drive! 2094 * 2095 * Still, in certain specialized circumstances the need may arise. This 2096 * routine gets around the normal restrictions by using a work thread to 2097 * submit the change-config request. 2098 * 2099 * Return: 0 if the request was successfully queued, error code otherwise. 2100 * The caller has no way to know whether the queued request will eventually 2101 * succeed. 2102 */ 2103 int usb_driver_set_configuration(struct usb_device *udev, int config) 2104 { 2105 struct set_config_request *req; 2106 2107 req = kmalloc(sizeof(*req), GFP_KERNEL); 2108 if (!req) 2109 return -ENOMEM; 2110 req->udev = udev; 2111 req->config = config; 2112 INIT_WORK(&req->work, driver_set_config_work); 2113 2114 spin_lock(&set_config_lock); 2115 list_add(&req->node, &set_config_list); 2116 spin_unlock(&set_config_lock); 2117 2118 usb_get_dev(udev); 2119 schedule_work(&req->work); 2120 return 0; 2121 } 2122 EXPORT_SYMBOL_GPL(usb_driver_set_configuration); 2123 2124 /** 2125 * cdc_parse_cdc_header - parse the extra headers present in CDC devices 2126 * @hdr: the place to put the results of the parsing 2127 * @intf: the interface for which parsing is requested 2128 * @buffer: pointer to the extra headers to be parsed 2129 * @buflen: length of the extra headers 2130 * 2131 * This evaluates the extra headers present in CDC devices which 2132 * bind the interfaces for data and control and provide details 2133 * about the capabilities of the device. 2134 * 2135 * Return: number of descriptors parsed or -EINVAL 2136 * if the header is contradictory beyond salvage 2137 */ 2138 2139 int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, 2140 struct usb_interface *intf, 2141 u8 *buffer, 2142 int buflen) 2143 { 2144 /* duplicates are ignored */ 2145 struct usb_cdc_union_desc *union_header = NULL; 2146 2147 /* duplicates are not tolerated */ 2148 struct usb_cdc_header_desc *header = NULL; 2149 struct usb_cdc_ether_desc *ether = NULL; 2150 struct usb_cdc_mdlm_detail_desc *detail = NULL; 2151 struct usb_cdc_mdlm_desc *desc = NULL; 2152 2153 unsigned int elength; 2154 int cnt = 0; 2155 2156 memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header)); 2157 hdr->phonet_magic_present = false; 2158 while (buflen > 0) { 2159 elength = buffer[0]; 2160 if (!elength) { 2161 dev_err(&intf->dev, "skipping garbage byte\n"); 2162 elength = 1; 2163 goto next_desc; 2164 } 2165 if ((buflen < elength) || (elength < 3)) { 2166 dev_err(&intf->dev, "invalid descriptor buffer length\n"); 2167 break; 2168 } 2169 if (buffer[1] != USB_DT_CS_INTERFACE) { 2170 dev_err(&intf->dev, "skipping garbage\n"); 2171 goto next_desc; 2172 } 2173 2174 switch (buffer[2]) { 2175 case USB_CDC_UNION_TYPE: /* we've found it */ 2176 if (elength < sizeof(struct usb_cdc_union_desc)) 2177 goto next_desc; 2178 if (union_header) { 2179 dev_err(&intf->dev, "More than one union descriptor, skipping ...\n"); 2180 goto next_desc; 2181 } 2182 union_header = (struct usb_cdc_union_desc *)buffer; 2183 break; 2184 case USB_CDC_COUNTRY_TYPE: 2185 if (elength < sizeof(struct usb_cdc_country_functional_desc)) 2186 goto next_desc; 2187 hdr->usb_cdc_country_functional_desc = 2188 (struct usb_cdc_country_functional_desc *)buffer; 2189 break; 2190 case USB_CDC_HEADER_TYPE: 2191 if (elength != sizeof(struct usb_cdc_header_desc)) 2192 goto next_desc; 2193 if (header) 2194 return -EINVAL; 2195 header = (struct usb_cdc_header_desc *)buffer; 2196 break; 2197 case USB_CDC_ACM_TYPE: 2198 if (elength < sizeof(struct usb_cdc_acm_descriptor)) 2199 goto next_desc; 2200 hdr->usb_cdc_acm_descriptor = 2201 (struct usb_cdc_acm_descriptor *)buffer; 2202 break; 2203 case USB_CDC_ETHERNET_TYPE: 2204 if (elength != sizeof(struct usb_cdc_ether_desc)) 2205 goto next_desc; 2206 if (ether) 2207 return -EINVAL; 2208 ether = (struct usb_cdc_ether_desc *)buffer; 2209 break; 2210 case USB_CDC_CALL_MANAGEMENT_TYPE: 2211 if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor)) 2212 goto next_desc; 2213 hdr->usb_cdc_call_mgmt_descriptor = 2214 (struct usb_cdc_call_mgmt_descriptor *)buffer; 2215 break; 2216 case USB_CDC_DMM_TYPE: 2217 if (elength < sizeof(struct usb_cdc_dmm_desc)) 2218 goto next_desc; 2219 hdr->usb_cdc_dmm_desc = 2220 (struct usb_cdc_dmm_desc *)buffer; 2221 break; 2222 case USB_CDC_MDLM_TYPE: 2223 if (elength < sizeof(struct usb_cdc_mdlm_desc)) 2224 goto next_desc; 2225 if (desc) 2226 return -EINVAL; 2227 desc = (struct usb_cdc_mdlm_desc *)buffer; 2228 break; 2229 case USB_CDC_MDLM_DETAIL_TYPE: 2230 if (elength < sizeof(struct usb_cdc_mdlm_detail_desc)) 2231 goto next_desc; 2232 if (detail) 2233 return -EINVAL; 2234 detail = (struct usb_cdc_mdlm_detail_desc *)buffer; 2235 break; 2236 case USB_CDC_NCM_TYPE: 2237 if (elength < sizeof(struct usb_cdc_ncm_desc)) 2238 goto next_desc; 2239 hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer; 2240 break; 2241 case USB_CDC_MBIM_TYPE: 2242 if (elength < sizeof(struct usb_cdc_mbim_desc)) 2243 goto next_desc; 2244 2245 hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer; 2246 break; 2247 case USB_CDC_MBIM_EXTENDED_TYPE: 2248 if (elength < sizeof(struct usb_cdc_mbim_extended_desc)) 2249 break; 2250 hdr->usb_cdc_mbim_extended_desc = 2251 (struct usb_cdc_mbim_extended_desc *)buffer; 2252 break; 2253 case CDC_PHONET_MAGIC_NUMBER: 2254 hdr->phonet_magic_present = true; 2255 break; 2256 default: 2257 /* 2258 * there are LOTS more CDC descriptors that 2259 * could legitimately be found here. 2260 */ 2261 dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n", 2262 buffer[2], elength); 2263 goto next_desc; 2264 } 2265 cnt++; 2266 next_desc: 2267 buflen -= elength; 2268 buffer += elength; 2269 } 2270 hdr->usb_cdc_union_desc = union_header; 2271 hdr->usb_cdc_header_desc = header; 2272 hdr->usb_cdc_mdlm_detail_desc = detail; 2273 hdr->usb_cdc_mdlm_desc = desc; 2274 hdr->usb_cdc_ether_desc = ether; 2275 return cnt; 2276 } 2277 2278 EXPORT_SYMBOL(cdc_parse_cdc_header); 2279