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) 1148 dev->ep_out[epnum] = NULL; 1149 } else { 1150 ep = dev->ep_in[epnum]; 1151 if (reset_hardware) 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 - Disable all the endpoints for a USB device 1210 * @dev: the device whose endpoints are being disabled 1211 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. 1212 * 1213 * Disables all the device's endpoints, potentially including endpoint 0. 1214 * Deallocates hcd/hardware state for the endpoints (nuking all or most 1215 * pending urbs) and usbcore state for the interfaces, so that usbcore 1216 * must usb_set_configuration() before any interfaces could be used. 1217 */ 1218 void usb_disable_device(struct usb_device *dev, int skip_ep0) 1219 { 1220 int i; 1221 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1222 1223 /* getting rid of interfaces will disconnect 1224 * any drivers bound to them (a key side effect) 1225 */ 1226 if (dev->actconfig) { 1227 /* 1228 * FIXME: In order to avoid self-deadlock involving the 1229 * bandwidth_mutex, we have to mark all the interfaces 1230 * before unregistering any of them. 1231 */ 1232 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) 1233 dev->actconfig->interface[i]->unregistering = 1; 1234 1235 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1236 struct usb_interface *interface; 1237 1238 /* remove this interface if it has been registered */ 1239 interface = dev->actconfig->interface[i]; 1240 if (!device_is_registered(&interface->dev)) 1241 continue; 1242 dev_dbg(&dev->dev, "unregistering interface %s\n", 1243 dev_name(&interface->dev)); 1244 remove_intf_ep_devs(interface); 1245 device_del(&interface->dev); 1246 } 1247 1248 /* Now that the interfaces are unbound, nobody should 1249 * try to access them. 1250 */ 1251 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { 1252 put_device(&dev->actconfig->interface[i]->dev); 1253 dev->actconfig->interface[i] = NULL; 1254 } 1255 1256 usb_disable_usb2_hardware_lpm(dev); 1257 usb_unlocked_disable_lpm(dev); 1258 usb_disable_ltm(dev); 1259 1260 dev->actconfig = NULL; 1261 if (dev->state == USB_STATE_CONFIGURED) 1262 usb_set_device_state(dev, USB_STATE_ADDRESS); 1263 } 1264 1265 dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__, 1266 skip_ep0 ? "non-ep0" : "all"); 1267 if (hcd->driver->check_bandwidth) { 1268 /* First pass: Cancel URBs, leave endpoint pointers intact. */ 1269 for (i = skip_ep0; i < 16; ++i) { 1270 usb_disable_endpoint(dev, i, false); 1271 usb_disable_endpoint(dev, i + USB_DIR_IN, false); 1272 } 1273 /* Remove endpoints from the host controller internal state */ 1274 mutex_lock(hcd->bandwidth_mutex); 1275 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1276 mutex_unlock(hcd->bandwidth_mutex); 1277 /* Second pass: remove endpoint pointers */ 1278 } 1279 for (i = skip_ep0; i < 16; ++i) { 1280 usb_disable_endpoint(dev, i, true); 1281 usb_disable_endpoint(dev, i + USB_DIR_IN, true); 1282 } 1283 } 1284 1285 /** 1286 * usb_enable_endpoint - Enable an endpoint for USB communications 1287 * @dev: the device whose interface is being enabled 1288 * @ep: the endpoint 1289 * @reset_ep: flag to reset the endpoint state 1290 * 1291 * Resets the endpoint state if asked, and sets dev->ep_{in,out} pointers. 1292 * For control endpoints, both the input and output sides are handled. 1293 */ 1294 void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep, 1295 bool reset_ep) 1296 { 1297 int epnum = usb_endpoint_num(&ep->desc); 1298 int is_out = usb_endpoint_dir_out(&ep->desc); 1299 int is_control = usb_endpoint_xfer_control(&ep->desc); 1300 1301 if (reset_ep) 1302 usb_hcd_reset_endpoint(dev, ep); 1303 if (is_out || is_control) 1304 dev->ep_out[epnum] = ep; 1305 if (!is_out || is_control) 1306 dev->ep_in[epnum] = ep; 1307 ep->enabled = 1; 1308 } 1309 1310 /** 1311 * usb_enable_interface - Enable all the endpoints for an interface 1312 * @dev: the device whose interface is being enabled 1313 * @intf: pointer to the interface descriptor 1314 * @reset_eps: flag to reset the endpoints' state 1315 * 1316 * Enables all the endpoints for the interface's current altsetting. 1317 */ 1318 void usb_enable_interface(struct usb_device *dev, 1319 struct usb_interface *intf, bool reset_eps) 1320 { 1321 struct usb_host_interface *alt = intf->cur_altsetting; 1322 int i; 1323 1324 for (i = 0; i < alt->desc.bNumEndpoints; ++i) 1325 usb_enable_endpoint(dev, &alt->endpoint[i], reset_eps); 1326 } 1327 1328 /** 1329 * usb_set_interface - Makes a particular alternate setting be current 1330 * @dev: the device whose interface is being updated 1331 * @interface: the interface being updated 1332 * @alternate: the setting being chosen. 1333 * Context: !in_interrupt () 1334 * 1335 * This is used to enable data transfers on interfaces that may not 1336 * be enabled by default. Not all devices support such configurability. 1337 * Only the driver bound to an interface may change its setting. 1338 * 1339 * Within any given configuration, each interface may have several 1340 * alternative settings. These are often used to control levels of 1341 * bandwidth consumption. For example, the default setting for a high 1342 * speed interrupt endpoint may not send more than 64 bytes per microframe, 1343 * while interrupt transfers of up to 3KBytes per microframe are legal. 1344 * Also, isochronous endpoints may never be part of an 1345 * interface's default setting. To access such bandwidth, alternate 1346 * interface settings must be made current. 1347 * 1348 * Note that in the Linux USB subsystem, bandwidth associated with 1349 * an endpoint in a given alternate setting is not reserved until an URB 1350 * is submitted that needs that bandwidth. Some other operating systems 1351 * allocate bandwidth early, when a configuration is chosen. 1352 * 1353 * xHCI reserves bandwidth and configures the alternate setting in 1354 * usb_hcd_alloc_bandwidth(). If it fails the original interface altsetting 1355 * may be disabled. Drivers cannot rely on any particular alternate 1356 * setting being in effect after a failure. 1357 * 1358 * This call is synchronous, and may not be used in an interrupt context. 1359 * Also, drivers must not change altsettings while urbs are scheduled for 1360 * endpoints in that interface; all such urbs must first be completed 1361 * (perhaps forced by unlinking). 1362 * 1363 * Return: Zero on success, or else the status code returned by the 1364 * underlying usb_control_msg() call. 1365 */ 1366 int usb_set_interface(struct usb_device *dev, int interface, int alternate) 1367 { 1368 struct usb_interface *iface; 1369 struct usb_host_interface *alt; 1370 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1371 int i, ret, manual = 0; 1372 unsigned int epaddr; 1373 unsigned int pipe; 1374 1375 if (dev->state == USB_STATE_SUSPENDED) 1376 return -EHOSTUNREACH; 1377 1378 iface = usb_ifnum_to_if(dev, interface); 1379 if (!iface) { 1380 dev_dbg(&dev->dev, "selecting invalid interface %d\n", 1381 interface); 1382 return -EINVAL; 1383 } 1384 if (iface->unregistering) 1385 return -ENODEV; 1386 1387 alt = usb_altnum_to_altsetting(iface, alternate); 1388 if (!alt) { 1389 dev_warn(&dev->dev, "selecting invalid altsetting %d\n", 1390 alternate); 1391 return -EINVAL; 1392 } 1393 /* 1394 * usb3 hosts configure the interface in usb_hcd_alloc_bandwidth, 1395 * including freeing dropped endpoint ring buffers. 1396 * Make sure the interface endpoints are flushed before that 1397 */ 1398 usb_disable_interface(dev, iface, false); 1399 1400 /* Make sure we have enough bandwidth for this alternate interface. 1401 * Remove the current alt setting and add the new alt setting. 1402 */ 1403 mutex_lock(hcd->bandwidth_mutex); 1404 /* Disable LPM, and re-enable it once the new alt setting is installed, 1405 * so that the xHCI driver can recalculate the U1/U2 timeouts. 1406 */ 1407 if (usb_disable_lpm(dev)) { 1408 dev_err(&iface->dev, "%s Failed to disable LPM\n", __func__); 1409 mutex_unlock(hcd->bandwidth_mutex); 1410 return -ENOMEM; 1411 } 1412 /* Changing alt-setting also frees any allocated streams */ 1413 for (i = 0; i < iface->cur_altsetting->desc.bNumEndpoints; i++) 1414 iface->cur_altsetting->endpoint[i].streams = 0; 1415 1416 ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt); 1417 if (ret < 0) { 1418 dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n", 1419 alternate); 1420 usb_enable_lpm(dev); 1421 mutex_unlock(hcd->bandwidth_mutex); 1422 return ret; 1423 } 1424 1425 if (dev->quirks & USB_QUIRK_NO_SET_INTF) 1426 ret = -EPIPE; 1427 else 1428 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1429 USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE, 1430 alternate, interface, NULL, 0, 5000); 1431 1432 /* 9.4.10 says devices don't need this and are free to STALL the 1433 * request if the interface only has one alternate setting. 1434 */ 1435 if (ret == -EPIPE && iface->num_altsetting == 1) { 1436 dev_dbg(&dev->dev, 1437 "manual set_interface for iface %d, alt %d\n", 1438 interface, alternate); 1439 manual = 1; 1440 } else if (ret < 0) { 1441 /* Re-instate the old alt setting */ 1442 usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting); 1443 usb_enable_lpm(dev); 1444 mutex_unlock(hcd->bandwidth_mutex); 1445 return ret; 1446 } 1447 mutex_unlock(hcd->bandwidth_mutex); 1448 1449 /* FIXME drivers shouldn't need to replicate/bugfix the logic here 1450 * when they implement async or easily-killable versions of this or 1451 * other "should-be-internal" functions (like clear_halt). 1452 * should hcd+usbcore postprocess control requests? 1453 */ 1454 1455 /* prevent submissions using previous endpoint settings */ 1456 if (iface->cur_altsetting != alt) { 1457 remove_intf_ep_devs(iface); 1458 usb_remove_sysfs_intf_files(iface); 1459 } 1460 usb_disable_interface(dev, iface, true); 1461 1462 iface->cur_altsetting = alt; 1463 1464 /* Now that the interface is installed, re-enable LPM. */ 1465 usb_unlocked_enable_lpm(dev); 1466 1467 /* If the interface only has one altsetting and the device didn't 1468 * accept the request, we attempt to carry out the equivalent action 1469 * by manually clearing the HALT feature for each endpoint in the 1470 * new altsetting. 1471 */ 1472 if (manual) { 1473 for (i = 0; i < alt->desc.bNumEndpoints; i++) { 1474 epaddr = alt->endpoint[i].desc.bEndpointAddress; 1475 pipe = __create_pipe(dev, 1476 USB_ENDPOINT_NUMBER_MASK & epaddr) | 1477 (usb_endpoint_out(epaddr) ? 1478 USB_DIR_OUT : USB_DIR_IN); 1479 1480 usb_clear_halt(dev, pipe); 1481 } 1482 } 1483 1484 /* 9.1.1.5: reset toggles for all endpoints in the new altsetting 1485 * 1486 * Note: 1487 * Despite EP0 is always present in all interfaces/AS, the list of 1488 * endpoints from the descriptor does not contain EP0. Due to its 1489 * omnipresence one might expect EP0 being considered "affected" by 1490 * any SetInterface request and hence assume toggles need to be reset. 1491 * However, EP0 toggles are re-synced for every individual transfer 1492 * during the SETUP stage - hence EP0 toggles are "don't care" here. 1493 * (Likewise, EP0 never "halts" on well designed devices.) 1494 */ 1495 usb_enable_interface(dev, iface, true); 1496 if (device_is_registered(&iface->dev)) { 1497 usb_create_sysfs_intf_files(iface); 1498 create_intf_ep_devs(iface); 1499 } 1500 return 0; 1501 } 1502 EXPORT_SYMBOL_GPL(usb_set_interface); 1503 1504 /** 1505 * usb_reset_configuration - lightweight device reset 1506 * @dev: the device whose configuration is being reset 1507 * 1508 * This issues a standard SET_CONFIGURATION request to the device using 1509 * the current configuration. The effect is to reset most USB-related 1510 * state in the device, including interface altsettings (reset to zero), 1511 * endpoint halts (cleared), and endpoint state (only for bulk and interrupt 1512 * endpoints). Other usbcore state is unchanged, including bindings of 1513 * usb device drivers to interfaces. 1514 * 1515 * Because this affects multiple interfaces, avoid using this with composite 1516 * (multi-interface) devices. Instead, the driver for each interface may 1517 * use usb_set_interface() on the interfaces it claims. Be careful though; 1518 * some devices don't support the SET_INTERFACE request, and others won't 1519 * reset all the interface state (notably endpoint state). Resetting the whole 1520 * configuration would affect other drivers' interfaces. 1521 * 1522 * The caller must own the device lock. 1523 * 1524 * Return: Zero on success, else a negative error code. 1525 */ 1526 int usb_reset_configuration(struct usb_device *dev) 1527 { 1528 int i, retval; 1529 struct usb_host_config *config; 1530 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1531 1532 if (dev->state == USB_STATE_SUSPENDED) 1533 return -EHOSTUNREACH; 1534 1535 /* caller must have locked the device and must own 1536 * the usb bus readlock (so driver bindings are stable); 1537 * calls during probe() are fine 1538 */ 1539 1540 for (i = 1; i < 16; ++i) { 1541 usb_disable_endpoint(dev, i, true); 1542 usb_disable_endpoint(dev, i + USB_DIR_IN, true); 1543 } 1544 1545 config = dev->actconfig; 1546 retval = 0; 1547 mutex_lock(hcd->bandwidth_mutex); 1548 /* Disable LPM, and re-enable it once the configuration is reset, so 1549 * that the xHCI driver can recalculate the U1/U2 timeouts. 1550 */ 1551 if (usb_disable_lpm(dev)) { 1552 dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); 1553 mutex_unlock(hcd->bandwidth_mutex); 1554 return -ENOMEM; 1555 } 1556 /* Make sure we have enough bandwidth for each alternate setting 0 */ 1557 for (i = 0; i < config->desc.bNumInterfaces; i++) { 1558 struct usb_interface *intf = config->interface[i]; 1559 struct usb_host_interface *alt; 1560 1561 alt = usb_altnum_to_altsetting(intf, 0); 1562 if (!alt) 1563 alt = &intf->altsetting[0]; 1564 if (alt != intf->cur_altsetting) 1565 retval = usb_hcd_alloc_bandwidth(dev, NULL, 1566 intf->cur_altsetting, alt); 1567 if (retval < 0) 1568 break; 1569 } 1570 /* If not, reinstate the old alternate settings */ 1571 if (retval < 0) { 1572 reset_old_alts: 1573 for (i--; i >= 0; i--) { 1574 struct usb_interface *intf = config->interface[i]; 1575 struct usb_host_interface *alt; 1576 1577 alt = usb_altnum_to_altsetting(intf, 0); 1578 if (!alt) 1579 alt = &intf->altsetting[0]; 1580 if (alt != intf->cur_altsetting) 1581 usb_hcd_alloc_bandwidth(dev, NULL, 1582 alt, intf->cur_altsetting); 1583 } 1584 usb_enable_lpm(dev); 1585 mutex_unlock(hcd->bandwidth_mutex); 1586 return retval; 1587 } 1588 retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1589 USB_REQ_SET_CONFIGURATION, 0, 1590 config->desc.bConfigurationValue, 0, 1591 NULL, 0, USB_CTRL_SET_TIMEOUT); 1592 if (retval < 0) 1593 goto reset_old_alts; 1594 mutex_unlock(hcd->bandwidth_mutex); 1595 1596 /* re-init hc/hcd interface/endpoint state */ 1597 for (i = 0; i < config->desc.bNumInterfaces; i++) { 1598 struct usb_interface *intf = config->interface[i]; 1599 struct usb_host_interface *alt; 1600 1601 alt = usb_altnum_to_altsetting(intf, 0); 1602 1603 /* No altsetting 0? We'll assume the first altsetting. 1604 * We could use a GetInterface call, but if a device is 1605 * so non-compliant that it doesn't have altsetting 0 1606 * then I wouldn't trust its reply anyway. 1607 */ 1608 if (!alt) 1609 alt = &intf->altsetting[0]; 1610 1611 if (alt != intf->cur_altsetting) { 1612 remove_intf_ep_devs(intf); 1613 usb_remove_sysfs_intf_files(intf); 1614 } 1615 intf->cur_altsetting = alt; 1616 usb_enable_interface(dev, intf, true); 1617 if (device_is_registered(&intf->dev)) { 1618 usb_create_sysfs_intf_files(intf); 1619 create_intf_ep_devs(intf); 1620 } 1621 } 1622 /* Now that the interfaces are installed, re-enable LPM. */ 1623 usb_unlocked_enable_lpm(dev); 1624 return 0; 1625 } 1626 EXPORT_SYMBOL_GPL(usb_reset_configuration); 1627 1628 static void usb_release_interface(struct device *dev) 1629 { 1630 struct usb_interface *intf = to_usb_interface(dev); 1631 struct usb_interface_cache *intfc = 1632 altsetting_to_usb_interface_cache(intf->altsetting); 1633 1634 kref_put(&intfc->ref, usb_release_interface_cache); 1635 usb_put_dev(interface_to_usbdev(intf)); 1636 of_node_put(dev->of_node); 1637 kfree(intf); 1638 } 1639 1640 /* 1641 * usb_deauthorize_interface - deauthorize an USB interface 1642 * 1643 * @intf: USB interface structure 1644 */ 1645 void usb_deauthorize_interface(struct usb_interface *intf) 1646 { 1647 struct device *dev = &intf->dev; 1648 1649 device_lock(dev->parent); 1650 1651 if (intf->authorized) { 1652 device_lock(dev); 1653 intf->authorized = 0; 1654 device_unlock(dev); 1655 1656 usb_forced_unbind_intf(intf); 1657 } 1658 1659 device_unlock(dev->parent); 1660 } 1661 1662 /* 1663 * usb_authorize_interface - authorize an USB interface 1664 * 1665 * @intf: USB interface structure 1666 */ 1667 void usb_authorize_interface(struct usb_interface *intf) 1668 { 1669 struct device *dev = &intf->dev; 1670 1671 if (!intf->authorized) { 1672 device_lock(dev); 1673 intf->authorized = 1; /* authorize interface */ 1674 device_unlock(dev); 1675 } 1676 } 1677 1678 static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env) 1679 { 1680 struct usb_device *usb_dev; 1681 struct usb_interface *intf; 1682 struct usb_host_interface *alt; 1683 1684 intf = to_usb_interface(dev); 1685 usb_dev = interface_to_usbdev(intf); 1686 alt = intf->cur_altsetting; 1687 1688 if (add_uevent_var(env, "INTERFACE=%d/%d/%d", 1689 alt->desc.bInterfaceClass, 1690 alt->desc.bInterfaceSubClass, 1691 alt->desc.bInterfaceProtocol)) 1692 return -ENOMEM; 1693 1694 if (add_uevent_var(env, 1695 "MODALIAS=usb:" 1696 "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02Xin%02X", 1697 le16_to_cpu(usb_dev->descriptor.idVendor), 1698 le16_to_cpu(usb_dev->descriptor.idProduct), 1699 le16_to_cpu(usb_dev->descriptor.bcdDevice), 1700 usb_dev->descriptor.bDeviceClass, 1701 usb_dev->descriptor.bDeviceSubClass, 1702 usb_dev->descriptor.bDeviceProtocol, 1703 alt->desc.bInterfaceClass, 1704 alt->desc.bInterfaceSubClass, 1705 alt->desc.bInterfaceProtocol, 1706 alt->desc.bInterfaceNumber)) 1707 return -ENOMEM; 1708 1709 return 0; 1710 } 1711 1712 struct device_type usb_if_device_type = { 1713 .name = "usb_interface", 1714 .release = usb_release_interface, 1715 .uevent = usb_if_uevent, 1716 }; 1717 1718 static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev, 1719 struct usb_host_config *config, 1720 u8 inum) 1721 { 1722 struct usb_interface_assoc_descriptor *retval = NULL; 1723 struct usb_interface_assoc_descriptor *intf_assoc; 1724 int first_intf; 1725 int last_intf; 1726 int i; 1727 1728 for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) { 1729 intf_assoc = config->intf_assoc[i]; 1730 if (intf_assoc->bInterfaceCount == 0) 1731 continue; 1732 1733 first_intf = intf_assoc->bFirstInterface; 1734 last_intf = first_intf + (intf_assoc->bInterfaceCount - 1); 1735 if (inum >= first_intf && inum <= last_intf) { 1736 if (!retval) 1737 retval = intf_assoc; 1738 else 1739 dev_err(&dev->dev, "Interface #%d referenced" 1740 " by multiple IADs\n", inum); 1741 } 1742 } 1743 1744 return retval; 1745 } 1746 1747 1748 /* 1749 * Internal function to queue a device reset 1750 * See usb_queue_reset_device() for more details 1751 */ 1752 static void __usb_queue_reset_device(struct work_struct *ws) 1753 { 1754 int rc; 1755 struct usb_interface *iface = 1756 container_of(ws, struct usb_interface, reset_ws); 1757 struct usb_device *udev = interface_to_usbdev(iface); 1758 1759 rc = usb_lock_device_for_reset(udev, iface); 1760 if (rc >= 0) { 1761 usb_reset_device(udev); 1762 usb_unlock_device(udev); 1763 } 1764 usb_put_intf(iface); /* Undo _get_ in usb_queue_reset_device() */ 1765 } 1766 1767 1768 /* 1769 * usb_set_configuration - Makes a particular device setting be current 1770 * @dev: the device whose configuration is being updated 1771 * @configuration: the configuration being chosen. 1772 * Context: !in_interrupt(), caller owns the device lock 1773 * 1774 * This is used to enable non-default device modes. Not all devices 1775 * use this kind of configurability; many devices only have one 1776 * configuration. 1777 * 1778 * @configuration is the value of the configuration to be installed. 1779 * According to the USB spec (e.g. section 9.1.1.5), configuration values 1780 * must be non-zero; a value of zero indicates that the device in 1781 * unconfigured. However some devices erroneously use 0 as one of their 1782 * configuration values. To help manage such devices, this routine will 1783 * accept @configuration = -1 as indicating the device should be put in 1784 * an unconfigured state. 1785 * 1786 * USB device configurations may affect Linux interoperability, 1787 * power consumption and the functionality available. For example, 1788 * the default configuration is limited to using 100mA of bus power, 1789 * so that when certain device functionality requires more power, 1790 * and the device is bus powered, that functionality should be in some 1791 * non-default device configuration. Other device modes may also be 1792 * reflected as configuration options, such as whether two ISDN 1793 * channels are available independently; and choosing between open 1794 * standard device protocols (like CDC) or proprietary ones. 1795 * 1796 * Note that a non-authorized device (dev->authorized == 0) will only 1797 * be put in unconfigured mode. 1798 * 1799 * Note that USB has an additional level of device configurability, 1800 * associated with interfaces. That configurability is accessed using 1801 * usb_set_interface(). 1802 * 1803 * This call is synchronous. The calling context must be able to sleep, 1804 * must own the device lock, and must not hold the driver model's USB 1805 * bus mutex; usb interface driver probe() methods cannot use this routine. 1806 * 1807 * Returns zero on success, or else the status code returned by the 1808 * underlying call that failed. On successful completion, each interface 1809 * in the original device configuration has been destroyed, and each one 1810 * in the new configuration has been probed by all relevant usb device 1811 * drivers currently known to the kernel. 1812 */ 1813 int usb_set_configuration(struct usb_device *dev, int configuration) 1814 { 1815 int i, ret; 1816 struct usb_host_config *cp = NULL; 1817 struct usb_interface **new_interfaces = NULL; 1818 struct usb_hcd *hcd = bus_to_hcd(dev->bus); 1819 int n, nintf; 1820 1821 if (dev->authorized == 0 || configuration == -1) 1822 configuration = 0; 1823 else { 1824 for (i = 0; i < dev->descriptor.bNumConfigurations; i++) { 1825 if (dev->config[i].desc.bConfigurationValue == 1826 configuration) { 1827 cp = &dev->config[i]; 1828 break; 1829 } 1830 } 1831 } 1832 if ((!cp && configuration != 0)) 1833 return -EINVAL; 1834 1835 /* The USB spec says configuration 0 means unconfigured. 1836 * But if a device includes a configuration numbered 0, 1837 * we will accept it as a correctly configured state. 1838 * Use -1 if you really want to unconfigure the device. 1839 */ 1840 if (cp && configuration == 0) 1841 dev_warn(&dev->dev, "config 0 descriptor??\n"); 1842 1843 /* Allocate memory for new interfaces before doing anything else, 1844 * so that if we run out then nothing will have changed. */ 1845 n = nintf = 0; 1846 if (cp) { 1847 nintf = cp->desc.bNumInterfaces; 1848 new_interfaces = kmalloc_array(nintf, sizeof(*new_interfaces), 1849 GFP_NOIO); 1850 if (!new_interfaces) 1851 return -ENOMEM; 1852 1853 for (; n < nintf; ++n) { 1854 new_interfaces[n] = kzalloc( 1855 sizeof(struct usb_interface), 1856 GFP_NOIO); 1857 if (!new_interfaces[n]) { 1858 ret = -ENOMEM; 1859 free_interfaces: 1860 while (--n >= 0) 1861 kfree(new_interfaces[n]); 1862 kfree(new_interfaces); 1863 return ret; 1864 } 1865 } 1866 1867 i = dev->bus_mA - usb_get_max_power(dev, cp); 1868 if (i < 0) 1869 dev_warn(&dev->dev, "new config #%d exceeds power " 1870 "limit by %dmA\n", 1871 configuration, -i); 1872 } 1873 1874 /* Wake up the device so we can send it the Set-Config request */ 1875 ret = usb_autoresume_device(dev); 1876 if (ret) 1877 goto free_interfaces; 1878 1879 /* if it's already configured, clear out old state first. 1880 * getting rid of old interfaces means unbinding their drivers. 1881 */ 1882 if (dev->state != USB_STATE_ADDRESS) 1883 usb_disable_device(dev, 1); /* Skip ep0 */ 1884 1885 /* Get rid of pending async Set-Config requests for this device */ 1886 cancel_async_set_config(dev); 1887 1888 /* Make sure we have bandwidth (and available HCD resources) for this 1889 * configuration. Remove endpoints from the schedule if we're dropping 1890 * this configuration to set configuration 0. After this point, the 1891 * host controller will not allow submissions to dropped endpoints. If 1892 * this call fails, the device state is unchanged. 1893 */ 1894 mutex_lock(hcd->bandwidth_mutex); 1895 /* Disable LPM, and re-enable it once the new configuration is 1896 * installed, so that the xHCI driver can recalculate the U1/U2 1897 * timeouts. 1898 */ 1899 if (dev->actconfig && usb_disable_lpm(dev)) { 1900 dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); 1901 mutex_unlock(hcd->bandwidth_mutex); 1902 ret = -ENOMEM; 1903 goto free_interfaces; 1904 } 1905 ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL); 1906 if (ret < 0) { 1907 if (dev->actconfig) 1908 usb_enable_lpm(dev); 1909 mutex_unlock(hcd->bandwidth_mutex); 1910 usb_autosuspend_device(dev); 1911 goto free_interfaces; 1912 } 1913 1914 /* 1915 * Initialize the new interface structures and the 1916 * hc/hcd/usbcore interface/endpoint state. 1917 */ 1918 for (i = 0; i < nintf; ++i) { 1919 struct usb_interface_cache *intfc; 1920 struct usb_interface *intf; 1921 struct usb_host_interface *alt; 1922 u8 ifnum; 1923 1924 cp->interface[i] = intf = new_interfaces[i]; 1925 intfc = cp->intf_cache[i]; 1926 intf->altsetting = intfc->altsetting; 1927 intf->num_altsetting = intfc->num_altsetting; 1928 intf->authorized = !!HCD_INTF_AUTHORIZED(hcd); 1929 kref_get(&intfc->ref); 1930 1931 alt = usb_altnum_to_altsetting(intf, 0); 1932 1933 /* No altsetting 0? We'll assume the first altsetting. 1934 * We could use a GetInterface call, but if a device is 1935 * so non-compliant that it doesn't have altsetting 0 1936 * then I wouldn't trust its reply anyway. 1937 */ 1938 if (!alt) 1939 alt = &intf->altsetting[0]; 1940 1941 ifnum = alt->desc.bInterfaceNumber; 1942 intf->intf_assoc = find_iad(dev, cp, ifnum); 1943 intf->cur_altsetting = alt; 1944 usb_enable_interface(dev, intf, true); 1945 intf->dev.parent = &dev->dev; 1946 if (usb_of_has_combined_node(dev)) { 1947 device_set_of_node_from_dev(&intf->dev, &dev->dev); 1948 } else { 1949 intf->dev.of_node = usb_of_get_interface_node(dev, 1950 configuration, ifnum); 1951 } 1952 ACPI_COMPANION_SET(&intf->dev, ACPI_COMPANION(&dev->dev)); 1953 intf->dev.driver = NULL; 1954 intf->dev.bus = &usb_bus_type; 1955 intf->dev.type = &usb_if_device_type; 1956 intf->dev.groups = usb_interface_groups; 1957 /* 1958 * Please refer to usb_alloc_dev() to see why we set 1959 * dma_mask and dma_pfn_offset. 1960 */ 1961 intf->dev.dma_mask = dev->dev.dma_mask; 1962 intf->dev.dma_pfn_offset = dev->dev.dma_pfn_offset; 1963 INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); 1964 intf->minor = -1; 1965 device_initialize(&intf->dev); 1966 pm_runtime_no_callbacks(&intf->dev); 1967 dev_set_name(&intf->dev, "%d-%s:%d.%d", dev->bus->busnum, 1968 dev->devpath, configuration, ifnum); 1969 usb_get_dev(dev); 1970 } 1971 kfree(new_interfaces); 1972 1973 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), 1974 USB_REQ_SET_CONFIGURATION, 0, configuration, 0, 1975 NULL, 0, USB_CTRL_SET_TIMEOUT); 1976 if (ret < 0 && cp) { 1977 /* 1978 * All the old state is gone, so what else can we do? 1979 * The device is probably useless now anyway. 1980 */ 1981 usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); 1982 for (i = 0; i < nintf; ++i) { 1983 usb_disable_interface(dev, cp->interface[i], true); 1984 put_device(&cp->interface[i]->dev); 1985 cp->interface[i] = NULL; 1986 } 1987 cp = NULL; 1988 } 1989 1990 dev->actconfig = cp; 1991 mutex_unlock(hcd->bandwidth_mutex); 1992 1993 if (!cp) { 1994 usb_set_device_state(dev, USB_STATE_ADDRESS); 1995 1996 /* Leave LPM disabled while the device is unconfigured. */ 1997 usb_autosuspend_device(dev); 1998 return ret; 1999 } 2000 usb_set_device_state(dev, USB_STATE_CONFIGURED); 2001 2002 if (cp->string == NULL && 2003 !(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS)) 2004 cp->string = usb_cache_string(dev, cp->desc.iConfiguration); 2005 2006 /* Now that the interfaces are installed, re-enable LPM. */ 2007 usb_unlocked_enable_lpm(dev); 2008 /* Enable LTM if it was turned off by usb_disable_device. */ 2009 usb_enable_ltm(dev); 2010 2011 /* Now that all the interfaces are set up, register them 2012 * to trigger binding of drivers to interfaces. probe() 2013 * routines may install different altsettings and may 2014 * claim() any interfaces not yet bound. Many class drivers 2015 * need that: CDC, audio, video, etc. 2016 */ 2017 for (i = 0; i < nintf; ++i) { 2018 struct usb_interface *intf = cp->interface[i]; 2019 2020 if (intf->dev.of_node && 2021 !of_device_is_available(intf->dev.of_node)) { 2022 dev_info(&dev->dev, "skipping disabled interface %d\n", 2023 intf->cur_altsetting->desc.bInterfaceNumber); 2024 continue; 2025 } 2026 2027 dev_dbg(&dev->dev, 2028 "adding %s (config #%d, interface %d)\n", 2029 dev_name(&intf->dev), configuration, 2030 intf->cur_altsetting->desc.bInterfaceNumber); 2031 device_enable_async_suspend(&intf->dev); 2032 ret = device_add(&intf->dev); 2033 if (ret != 0) { 2034 dev_err(&dev->dev, "device_add(%s) --> %d\n", 2035 dev_name(&intf->dev), ret); 2036 continue; 2037 } 2038 create_intf_ep_devs(intf); 2039 } 2040 2041 usb_autosuspend_device(dev); 2042 return 0; 2043 } 2044 EXPORT_SYMBOL_GPL(usb_set_configuration); 2045 2046 static LIST_HEAD(set_config_list); 2047 static DEFINE_SPINLOCK(set_config_lock); 2048 2049 struct set_config_request { 2050 struct usb_device *udev; 2051 int config; 2052 struct work_struct work; 2053 struct list_head node; 2054 }; 2055 2056 /* Worker routine for usb_driver_set_configuration() */ 2057 static void driver_set_config_work(struct work_struct *work) 2058 { 2059 struct set_config_request *req = 2060 container_of(work, struct set_config_request, work); 2061 struct usb_device *udev = req->udev; 2062 2063 usb_lock_device(udev); 2064 spin_lock(&set_config_lock); 2065 list_del(&req->node); 2066 spin_unlock(&set_config_lock); 2067 2068 if (req->config >= -1) /* Is req still valid? */ 2069 usb_set_configuration(udev, req->config); 2070 usb_unlock_device(udev); 2071 usb_put_dev(udev); 2072 kfree(req); 2073 } 2074 2075 /* Cancel pending Set-Config requests for a device whose configuration 2076 * was just changed 2077 */ 2078 static void cancel_async_set_config(struct usb_device *udev) 2079 { 2080 struct set_config_request *req; 2081 2082 spin_lock(&set_config_lock); 2083 list_for_each_entry(req, &set_config_list, node) { 2084 if (req->udev == udev) 2085 req->config = -999; /* Mark as cancelled */ 2086 } 2087 spin_unlock(&set_config_lock); 2088 } 2089 2090 /** 2091 * usb_driver_set_configuration - Provide a way for drivers to change device configurations 2092 * @udev: the device whose configuration is being updated 2093 * @config: the configuration being chosen. 2094 * Context: In process context, must be able to sleep 2095 * 2096 * Device interface drivers are not allowed to change device configurations. 2097 * This is because changing configurations will destroy the interface the 2098 * driver is bound to and create new ones; it would be like a floppy-disk 2099 * driver telling the computer to replace the floppy-disk drive with a 2100 * tape drive! 2101 * 2102 * Still, in certain specialized circumstances the need may arise. This 2103 * routine gets around the normal restrictions by using a work thread to 2104 * submit the change-config request. 2105 * 2106 * Return: 0 if the request was successfully queued, error code otherwise. 2107 * The caller has no way to know whether the queued request will eventually 2108 * succeed. 2109 */ 2110 int usb_driver_set_configuration(struct usb_device *udev, int config) 2111 { 2112 struct set_config_request *req; 2113 2114 req = kmalloc(sizeof(*req), GFP_KERNEL); 2115 if (!req) 2116 return -ENOMEM; 2117 req->udev = udev; 2118 req->config = config; 2119 INIT_WORK(&req->work, driver_set_config_work); 2120 2121 spin_lock(&set_config_lock); 2122 list_add(&req->node, &set_config_list); 2123 spin_unlock(&set_config_lock); 2124 2125 usb_get_dev(udev); 2126 schedule_work(&req->work); 2127 return 0; 2128 } 2129 EXPORT_SYMBOL_GPL(usb_driver_set_configuration); 2130 2131 /** 2132 * cdc_parse_cdc_header - parse the extra headers present in CDC devices 2133 * @hdr: the place to put the results of the parsing 2134 * @intf: the interface for which parsing is requested 2135 * @buffer: pointer to the extra headers to be parsed 2136 * @buflen: length of the extra headers 2137 * 2138 * This evaluates the extra headers present in CDC devices which 2139 * bind the interfaces for data and control and provide details 2140 * about the capabilities of the device. 2141 * 2142 * Return: number of descriptors parsed or -EINVAL 2143 * if the header is contradictory beyond salvage 2144 */ 2145 2146 int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, 2147 struct usb_interface *intf, 2148 u8 *buffer, 2149 int buflen) 2150 { 2151 /* duplicates are ignored */ 2152 struct usb_cdc_union_desc *union_header = NULL; 2153 2154 /* duplicates are not tolerated */ 2155 struct usb_cdc_header_desc *header = NULL; 2156 struct usb_cdc_ether_desc *ether = NULL; 2157 struct usb_cdc_mdlm_detail_desc *detail = NULL; 2158 struct usb_cdc_mdlm_desc *desc = NULL; 2159 2160 unsigned int elength; 2161 int cnt = 0; 2162 2163 memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header)); 2164 hdr->phonet_magic_present = false; 2165 while (buflen > 0) { 2166 elength = buffer[0]; 2167 if (!elength) { 2168 dev_err(&intf->dev, "skipping garbage byte\n"); 2169 elength = 1; 2170 goto next_desc; 2171 } 2172 if ((buflen < elength) || (elength < 3)) { 2173 dev_err(&intf->dev, "invalid descriptor buffer length\n"); 2174 break; 2175 } 2176 if (buffer[1] != USB_DT_CS_INTERFACE) { 2177 dev_err(&intf->dev, "skipping garbage\n"); 2178 goto next_desc; 2179 } 2180 2181 switch (buffer[2]) { 2182 case USB_CDC_UNION_TYPE: /* we've found it */ 2183 if (elength < sizeof(struct usb_cdc_union_desc)) 2184 goto next_desc; 2185 if (union_header) { 2186 dev_err(&intf->dev, "More than one union descriptor, skipping ...\n"); 2187 goto next_desc; 2188 } 2189 union_header = (struct usb_cdc_union_desc *)buffer; 2190 break; 2191 case USB_CDC_COUNTRY_TYPE: 2192 if (elength < sizeof(struct usb_cdc_country_functional_desc)) 2193 goto next_desc; 2194 hdr->usb_cdc_country_functional_desc = 2195 (struct usb_cdc_country_functional_desc *)buffer; 2196 break; 2197 case USB_CDC_HEADER_TYPE: 2198 if (elength != sizeof(struct usb_cdc_header_desc)) 2199 goto next_desc; 2200 if (header) 2201 return -EINVAL; 2202 header = (struct usb_cdc_header_desc *)buffer; 2203 break; 2204 case USB_CDC_ACM_TYPE: 2205 if (elength < sizeof(struct usb_cdc_acm_descriptor)) 2206 goto next_desc; 2207 hdr->usb_cdc_acm_descriptor = 2208 (struct usb_cdc_acm_descriptor *)buffer; 2209 break; 2210 case USB_CDC_ETHERNET_TYPE: 2211 if (elength != sizeof(struct usb_cdc_ether_desc)) 2212 goto next_desc; 2213 if (ether) 2214 return -EINVAL; 2215 ether = (struct usb_cdc_ether_desc *)buffer; 2216 break; 2217 case USB_CDC_CALL_MANAGEMENT_TYPE: 2218 if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor)) 2219 goto next_desc; 2220 hdr->usb_cdc_call_mgmt_descriptor = 2221 (struct usb_cdc_call_mgmt_descriptor *)buffer; 2222 break; 2223 case USB_CDC_DMM_TYPE: 2224 if (elength < sizeof(struct usb_cdc_dmm_desc)) 2225 goto next_desc; 2226 hdr->usb_cdc_dmm_desc = 2227 (struct usb_cdc_dmm_desc *)buffer; 2228 break; 2229 case USB_CDC_MDLM_TYPE: 2230 if (elength < sizeof(struct usb_cdc_mdlm_desc)) 2231 goto next_desc; 2232 if (desc) 2233 return -EINVAL; 2234 desc = (struct usb_cdc_mdlm_desc *)buffer; 2235 break; 2236 case USB_CDC_MDLM_DETAIL_TYPE: 2237 if (elength < sizeof(struct usb_cdc_mdlm_detail_desc)) 2238 goto next_desc; 2239 if (detail) 2240 return -EINVAL; 2241 detail = (struct usb_cdc_mdlm_detail_desc *)buffer; 2242 break; 2243 case USB_CDC_NCM_TYPE: 2244 if (elength < sizeof(struct usb_cdc_ncm_desc)) 2245 goto next_desc; 2246 hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer; 2247 break; 2248 case USB_CDC_MBIM_TYPE: 2249 if (elength < sizeof(struct usb_cdc_mbim_desc)) 2250 goto next_desc; 2251 2252 hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer; 2253 break; 2254 case USB_CDC_MBIM_EXTENDED_TYPE: 2255 if (elength < sizeof(struct usb_cdc_mbim_extended_desc)) 2256 break; 2257 hdr->usb_cdc_mbim_extended_desc = 2258 (struct usb_cdc_mbim_extended_desc *)buffer; 2259 break; 2260 case CDC_PHONET_MAGIC_NUMBER: 2261 hdr->phonet_magic_present = true; 2262 break; 2263 default: 2264 /* 2265 * there are LOTS more CDC descriptors that 2266 * could legitimately be found here. 2267 */ 2268 dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n", 2269 buffer[2], elength); 2270 goto next_desc; 2271 } 2272 cnt++; 2273 next_desc: 2274 buflen -= elength; 2275 buffer += elength; 2276 } 2277 hdr->usb_cdc_union_desc = union_header; 2278 hdr->usb_cdc_header_desc = header; 2279 hdr->usb_cdc_mdlm_detail_desc = detail; 2280 hdr->usb_cdc_mdlm_desc = desc; 2281 hdr->usb_cdc_ether_desc = ether; 2282 return cnt; 2283 } 2284 2285 EXPORT_SYMBOL(cdc_parse_cdc_header); 2286