1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 // #define DEBUG 1 18 #if DEBUG 19 20 #ifdef USE_LIBLOG 21 #define LOG_TAG "usbhost" 22 #include "utils/Log.h" 23 #define D ALOGD 24 #else 25 #define D printf 26 #endif 27 28 #else 29 #define D(...) 30 #endif 31 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <unistd.h> 35 #include <string.h> 36 #include <stddef.h> 37 38 #include <sys/ioctl.h> 39 #include <sys/types.h> 40 #include <sys/time.h> 41 #include <sys/inotify.h> 42 #include <dirent.h> 43 #include <fcntl.h> 44 #include <errno.h> 45 #include <ctype.h> 46 #include <pthread.h> 47 48 #include <linux/usbdevice_fs.h> 49 #include <asm/byteorder.h> 50 51 #include "usbhost/usbhost.h" 52 53 #define DEV_DIR "/dev" 54 #define DEV_BUS_DIR DEV_DIR "/bus" 55 #define USB_FS_DIR DEV_BUS_DIR "/usb" 56 #define USB_FS_ID_SCANNER USB_FS_DIR "/%d/%d" 57 #define USB_FS_ID_FORMAT USB_FS_DIR "/%03d/%03d" 58 59 // Some devices fail to send string descriptors if we attempt reading > 255 bytes 60 #define MAX_STRING_DESCRIPTOR_LENGTH 255 61 62 // From drivers/usb/core/devio.c 63 // I don't know why this isn't in a kernel header 64 #define MAX_USBFS_BUFFER_SIZE 16384 65 66 #define MAX_USBFS_WD_COUNT 10 67 68 struct usb_host_context { 69 int fd; 70 usb_device_added_cb cb_added; 71 usb_device_removed_cb cb_removed; 72 void *data; 73 int wds[MAX_USBFS_WD_COUNT]; 74 int wdd; 75 int wddbus; 76 }; 77 78 struct usb_device { 79 char dev_name[64]; 80 unsigned char desc[4096]; 81 int desc_length; 82 int fd; 83 int writeable; 84 }; 85 86 static inline int badname(const char *name) 87 { 88 while(*name) { 89 if(!isdigit(*name++)) return 1; 90 } 91 return 0; 92 } 93 94 static int find_existing_devices_bus(char *busname, 95 usb_device_added_cb added_cb, 96 void *client_data) 97 { 98 char devname[32]; 99 DIR *devdir; 100 struct dirent *de; 101 int done = 0; 102 103 devdir = opendir(busname); 104 if(devdir == 0) return 0; 105 106 while ((de = readdir(devdir)) && !done) { 107 if(badname(de->d_name)) continue; 108 109 snprintf(devname, sizeof(devname), "%s/%s", busname, de->d_name); 110 done = added_cb(devname, client_data); 111 } // end of devdir while 112 closedir(devdir); 113 114 return done; 115 } 116 117 /* returns true if one of the callbacks indicates we are done */ 118 static int find_existing_devices(usb_device_added_cb added_cb, 119 void *client_data) 120 { 121 char busname[32]; 122 DIR *busdir; 123 struct dirent *de; 124 int done = 0; 125 126 busdir = opendir(USB_FS_DIR); 127 if(busdir == 0) return 0; 128 129 while ((de = readdir(busdir)) != 0 && !done) { 130 if(badname(de->d_name)) continue; 131 132 snprintf(busname, sizeof(busname), USB_FS_DIR "/%s", de->d_name); 133 done = find_existing_devices_bus(busname, added_cb, 134 client_data); 135 } //end of busdir while 136 closedir(busdir); 137 138 return done; 139 } 140 141 static void watch_existing_subdirs(struct usb_host_context *context, 142 int *wds, int wd_count) 143 { 144 char path[100]; 145 int i, ret; 146 147 wds[0] = inotify_add_watch(context->fd, USB_FS_DIR, IN_CREATE | IN_DELETE); 148 if (wds[0] < 0) 149 return; 150 151 /* watch existing subdirectories of USB_FS_DIR */ 152 for (i = 1; i < wd_count; i++) { 153 snprintf(path, sizeof(path), USB_FS_DIR "/%03d", i); 154 ret = inotify_add_watch(context->fd, path, IN_CREATE | IN_DELETE); 155 if (ret >= 0) 156 wds[i] = ret; 157 } 158 } 159 160 struct usb_host_context *usb_host_init() 161 { 162 struct usb_host_context *context = calloc(1, sizeof(struct usb_host_context)); 163 if (!context) { 164 fprintf(stderr, "out of memory in usb_host_context\n"); 165 return NULL; 166 } 167 context->fd = inotify_init(); 168 if (context->fd < 0) { 169 fprintf(stderr, "inotify_init failed\n"); 170 free(context); 171 return NULL; 172 } 173 return context; 174 } 175 176 void usb_host_cleanup(struct usb_host_context *context) 177 { 178 close(context->fd); 179 free(context); 180 } 181 182 int usb_host_get_fd(struct usb_host_context *context) 183 { 184 return context->fd; 185 } /* usb_host_get_fd() */ 186 187 int usb_host_load(struct usb_host_context *context, 188 usb_device_added_cb added_cb, 189 usb_device_removed_cb removed_cb, 190 usb_discovery_done_cb discovery_done_cb, 191 void *client_data) 192 { 193 int done = 0; 194 int i; 195 196 context->cb_added = added_cb; 197 context->cb_removed = removed_cb; 198 context->data = client_data; 199 200 D("Created device discovery thread\n"); 201 202 /* watch for files added and deleted within USB_FS_DIR */ 203 context->wddbus = -1; 204 for (i = 0; i < MAX_USBFS_WD_COUNT; i++) 205 context->wds[i] = -1; 206 207 /* watch the root for new subdirectories */ 208 context->wdd = inotify_add_watch(context->fd, DEV_DIR, IN_CREATE | IN_DELETE); 209 if (context->wdd < 0) { 210 fprintf(stderr, "inotify_add_watch failed\n"); 211 if (discovery_done_cb) 212 discovery_done_cb(client_data); 213 return done; 214 } 215 216 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 217 218 /* check for existing devices first, after we have inotify set up */ 219 done = find_existing_devices(added_cb, client_data); 220 if (discovery_done_cb) 221 done |= discovery_done_cb(client_data); 222 223 return done; 224 } /* usb_host_load() */ 225 226 int usb_host_read_event(struct usb_host_context *context) 227 { 228 struct inotify_event* event; 229 char event_buf[512]; 230 char path[100]; 231 int i, ret, done = 0; 232 int offset = 0; 233 int wd; 234 235 ret = read(context->fd, event_buf, sizeof(event_buf)); 236 if (ret >= (int)sizeof(struct inotify_event)) { 237 while (offset < ret && !done) { 238 event = (struct inotify_event*)&event_buf[offset]; 239 done = 0; 240 wd = event->wd; 241 if (wd == context->wdd) { 242 if ((event->mask & IN_CREATE) && !strcmp(event->name, "bus")) { 243 context->wddbus = inotify_add_watch(context->fd, DEV_BUS_DIR, IN_CREATE | IN_DELETE); 244 if (context->wddbus < 0) { 245 done = 1; 246 } else { 247 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 248 done = find_existing_devices(context->cb_added, context->data); 249 } 250 } 251 } else if (wd == context->wddbus) { 252 if ((event->mask & IN_CREATE) && !strcmp(event->name, "usb")) { 253 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 254 done = find_existing_devices(context->cb_added, context->data); 255 } else if ((event->mask & IN_DELETE) && !strcmp(event->name, "usb")) { 256 for (i = 0; i < MAX_USBFS_WD_COUNT; i++) { 257 if (context->wds[i] >= 0) { 258 inotify_rm_watch(context->fd, context->wds[i]); 259 context->wds[i] = -1; 260 } 261 } 262 } 263 } else if (wd == context->wds[0]) { 264 i = atoi(event->name); 265 snprintf(path, sizeof(path), USB_FS_DIR "/%s", event->name); 266 D("%s subdirectory %s: index: %d\n", (event->mask & IN_CREATE) ? 267 "new" : "gone", path, i); 268 if (i > 0 && i < MAX_USBFS_WD_COUNT) { 269 int local_ret = 0; 270 if (event->mask & IN_CREATE) { 271 local_ret = inotify_add_watch(context->fd, path, 272 IN_CREATE | IN_DELETE); 273 if (local_ret >= 0) 274 context->wds[i] = local_ret; 275 done = find_existing_devices_bus(path, context->cb_added, 276 context->data); 277 } else if (event->mask & IN_DELETE) { 278 inotify_rm_watch(context->fd, context->wds[i]); 279 context->wds[i] = -1; 280 } 281 } 282 } else { 283 for (i = 1; (i < MAX_USBFS_WD_COUNT) && !done; i++) { 284 if (wd == context->wds[i]) { 285 snprintf(path, sizeof(path), USB_FS_DIR "/%03d/%s", i, event->name); 286 if (event->mask == IN_CREATE) { 287 D("new device %s\n", path); 288 done = context->cb_added(path, context->data); 289 } else if (event->mask == IN_DELETE) { 290 D("gone device %s\n", path); 291 done = context->cb_removed(path, context->data); 292 } 293 } 294 } 295 } 296 297 offset += sizeof(struct inotify_event) + event->len; 298 } 299 } 300 301 return done; 302 } /* usb_host_read_event() */ 303 304 void usb_host_run(struct usb_host_context *context, 305 usb_device_added_cb added_cb, 306 usb_device_removed_cb removed_cb, 307 usb_discovery_done_cb discovery_done_cb, 308 void *client_data) 309 { 310 int done; 311 312 done = usb_host_load(context, added_cb, removed_cb, discovery_done_cb, client_data); 313 314 while (!done) { 315 316 done = usb_host_read_event(context); 317 } 318 } /* usb_host_run() */ 319 320 struct usb_device *usb_device_open(const char *dev_name) 321 { 322 int fd, did_retry = 0, writeable = 1; 323 324 D("usb_device_open %s\n", dev_name); 325 326 retry: 327 fd = open(dev_name, O_RDWR); 328 if (fd < 0) { 329 /* if we fail, see if have read-only access */ 330 fd = open(dev_name, O_RDONLY); 331 D("usb_device_open open returned %d errno %d\n", fd, errno); 332 if (fd < 0 && (errno == EACCES || errno == ENOENT) && !did_retry) { 333 /* work around race condition between inotify and permissions management */ 334 sleep(1); 335 did_retry = 1; 336 goto retry; 337 } 338 339 if (fd < 0) 340 return NULL; 341 writeable = 0; 342 D("[ usb open read-only %s fd = %d]\n", dev_name, fd); 343 } 344 345 struct usb_device* result = usb_device_new(dev_name, fd); 346 if (result) 347 result->writeable = writeable; 348 return result; 349 } 350 351 void usb_device_close(struct usb_device *device) 352 { 353 close(device->fd); 354 free(device); 355 } 356 357 struct usb_device *usb_device_new(const char *dev_name, int fd) 358 { 359 struct usb_device *device = calloc(1, sizeof(struct usb_device)); 360 int length; 361 362 D("usb_device_new %s fd: %d\n", dev_name, fd); 363 364 if (lseek(fd, 0, SEEK_SET) != 0) 365 goto failed; 366 length = read(fd, device->desc, sizeof(device->desc)); 367 D("usb_device_new read returned %d errno %d\n", length, errno); 368 if (length < 0) 369 goto failed; 370 371 strncpy(device->dev_name, dev_name, sizeof(device->dev_name) - 1); 372 device->fd = fd; 373 device->desc_length = length; 374 // assume we are writeable, since usb_device_get_fd will only return writeable fds 375 device->writeable = 1; 376 return device; 377 378 failed: 379 close(fd); 380 free(device); 381 return NULL; 382 } 383 384 static int usb_device_reopen_writeable(struct usb_device *device) 385 { 386 if (device->writeable) 387 return 1; 388 389 int fd = open(device->dev_name, O_RDWR); 390 if (fd >= 0) { 391 close(device->fd); 392 device->fd = fd; 393 device->writeable = 1; 394 return 1; 395 } 396 D("usb_device_reopen_writeable failed errno %d\n", errno); 397 return 0; 398 } 399 400 int usb_device_get_fd(struct usb_device *device) 401 { 402 if (!usb_device_reopen_writeable(device)) 403 return -1; 404 return device->fd; 405 } 406 407 const char* usb_device_get_name(struct usb_device *device) 408 { 409 return device->dev_name; 410 } 411 412 int usb_device_get_unique_id(struct usb_device *device) 413 { 414 int bus = 0, dev = 0; 415 sscanf(device->dev_name, USB_FS_ID_SCANNER, &bus, &dev); 416 return bus * 1000 + dev; 417 } 418 419 int usb_device_get_unique_id_from_name(const char* name) 420 { 421 int bus = 0, dev = 0; 422 sscanf(name, USB_FS_ID_SCANNER, &bus, &dev); 423 return bus * 1000 + dev; 424 } 425 426 char* usb_device_get_name_from_unique_id(int id) 427 { 428 int bus = id / 1000; 429 int dev = id % 1000; 430 char* result = (char *)calloc(1, strlen(USB_FS_ID_FORMAT)); 431 snprintf(result, strlen(USB_FS_ID_FORMAT) - 1, USB_FS_ID_FORMAT, bus, dev); 432 return result; 433 } 434 435 uint16_t usb_device_get_vendor_id(struct usb_device *device) 436 { 437 struct usb_device_descriptor* desc = (struct usb_device_descriptor*)device->desc; 438 return __le16_to_cpu(desc->idVendor); 439 } 440 441 uint16_t usb_device_get_product_id(struct usb_device *device) 442 { 443 struct usb_device_descriptor* desc = (struct usb_device_descriptor*)device->desc; 444 return __le16_to_cpu(desc->idProduct); 445 } 446 447 const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device) 448 { 449 return (struct usb_device_descriptor*)device->desc; 450 } 451 452 char* usb_device_get_string(struct usb_device *device, int id) 453 { 454 char string[256]; 455 __u16 buffer[MAX_STRING_DESCRIPTOR_LENGTH / sizeof(__u16)]; 456 __u16 languages[MAX_STRING_DESCRIPTOR_LENGTH / sizeof(__u16)]; 457 int i, result; 458 int languageCount = 0; 459 460 if (id == 0) return NULL; 461 462 string[0] = 0; 463 memset(languages, 0, sizeof(languages)); 464 465 // read list of supported languages 466 result = usb_device_control_transfer(device, 467 USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE, USB_REQ_GET_DESCRIPTOR, 468 (USB_DT_STRING << 8) | 0, 0, languages, sizeof(languages), 0); 469 if (result > 0) 470 languageCount = (result - 2) / 2; 471 472 for (i = 1; i <= languageCount; i++) { 473 memset(buffer, 0, sizeof(buffer)); 474 475 result = usb_device_control_transfer(device, 476 USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE, USB_REQ_GET_DESCRIPTOR, 477 (USB_DT_STRING << 8) | id, languages[i], buffer, sizeof(buffer), 0); 478 if (result > 0) { 479 int i; 480 // skip first word, and copy the rest to the string, changing shorts to bytes. 481 result /= 2; 482 for (i = 1; i < result; i++) 483 string[i - 1] = buffer[i]; 484 string[i - 1] = 0; 485 return strdup(string); 486 } 487 } 488 489 return NULL; 490 } 491 492 char* usb_device_get_manufacturer_name(struct usb_device *device) 493 { 494 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 495 return usb_device_get_string(device, desc->iManufacturer); 496 } 497 498 char* usb_device_get_product_name(struct usb_device *device) 499 { 500 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 501 return usb_device_get_string(device, desc->iProduct); 502 } 503 504 int usb_device_get_version(struct usb_device *device) 505 { 506 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 507 return desc->bcdUSB; 508 } 509 510 char* usb_device_get_serial(struct usb_device *device) 511 { 512 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 513 return usb_device_get_string(device, desc->iSerialNumber); 514 } 515 516 int usb_device_is_writeable(struct usb_device *device) 517 { 518 return device->writeable; 519 } 520 521 void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter) 522 { 523 iter->config = device->desc; 524 iter->config_end = device->desc + device->desc_length; 525 iter->curr_desc = device->desc; 526 } 527 528 struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter) 529 { 530 struct usb_descriptor_header* next; 531 if (iter->curr_desc >= iter->config_end) 532 return NULL; 533 next = (struct usb_descriptor_header*)iter->curr_desc; 534 iter->curr_desc += next->bLength; 535 return next; 536 } 537 538 int usb_device_claim_interface(struct usb_device *device, unsigned int interface) 539 { 540 return ioctl(device->fd, USBDEVFS_CLAIMINTERFACE, &interface); 541 } 542 543 int usb_device_release_interface(struct usb_device *device, unsigned int interface) 544 { 545 return ioctl(device->fd, USBDEVFS_RELEASEINTERFACE, &interface); 546 } 547 548 int usb_device_connect_kernel_driver(struct usb_device *device, 549 unsigned int interface, int connect) 550 { 551 struct usbdevfs_ioctl ctl; 552 553 ctl.ifno = interface; 554 ctl.ioctl_code = (connect ? USBDEVFS_CONNECT : USBDEVFS_DISCONNECT); 555 ctl.data = NULL; 556 return ioctl(device->fd, USBDEVFS_IOCTL, &ctl); 557 } 558 559 int usb_device_set_configuration(struct usb_device *device, int configuration) 560 { 561 return ioctl(device->fd, USBDEVFS_SETCONFIGURATION, &configuration); 562 } 563 564 int usb_device_set_interface(struct usb_device *device, unsigned int interface, 565 unsigned int alt_setting) 566 { 567 struct usbdevfs_setinterface ctl; 568 569 ctl.interface = interface; 570 ctl.altsetting = alt_setting; 571 return ioctl(device->fd, USBDEVFS_SETINTERFACE, &ctl); 572 } 573 574 int usb_device_control_transfer(struct usb_device *device, 575 int requestType, 576 int request, 577 int value, 578 int index, 579 void* buffer, 580 int length, 581 unsigned int timeout) 582 { 583 struct usbdevfs_ctrltransfer ctrl; 584 585 // this usually requires read/write permission 586 if (!usb_device_reopen_writeable(device)) 587 return -1; 588 589 memset(&ctrl, 0, sizeof(ctrl)); 590 ctrl.bRequestType = requestType; 591 ctrl.bRequest = request; 592 ctrl.wValue = value; 593 ctrl.wIndex = index; 594 ctrl.wLength = length; 595 ctrl.data = buffer; 596 ctrl.timeout = timeout; 597 return ioctl(device->fd, USBDEVFS_CONTROL, &ctrl); 598 } 599 600 int usb_device_bulk_transfer(struct usb_device *device, 601 int endpoint, 602 void* buffer, 603 int length, 604 unsigned int timeout) 605 { 606 struct usbdevfs_bulktransfer ctrl; 607 608 // need to limit request size to avoid EINVAL 609 if (length > MAX_USBFS_BUFFER_SIZE) 610 length = MAX_USBFS_BUFFER_SIZE; 611 612 memset(&ctrl, 0, sizeof(ctrl)); 613 ctrl.ep = endpoint; 614 ctrl.len = length; 615 ctrl.data = buffer; 616 ctrl.timeout = timeout; 617 return ioctl(device->fd, USBDEVFS_BULK, &ctrl); 618 } 619 620 struct usb_request *usb_request_new(struct usb_device *dev, 621 const struct usb_endpoint_descriptor *ep_desc) 622 { 623 struct usbdevfs_urb *urb = calloc(1, sizeof(struct usbdevfs_urb)); 624 if (!urb) 625 return NULL; 626 627 if ((ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_BULK) 628 urb->type = USBDEVFS_URB_TYPE_BULK; 629 else if ((ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT) 630 urb->type = USBDEVFS_URB_TYPE_INTERRUPT; 631 else { 632 D("Unsupported endpoint type %d", ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); 633 free(urb); 634 return NULL; 635 } 636 urb->endpoint = ep_desc->bEndpointAddress; 637 638 struct usb_request *req = calloc(1, sizeof(struct usb_request)); 639 if (!req) { 640 free(urb); 641 return NULL; 642 } 643 644 req->dev = dev; 645 req->max_packet_size = __le16_to_cpu(ep_desc->wMaxPacketSize); 646 req->private_data = urb; 647 req->endpoint = urb->endpoint; 648 urb->usercontext = req; 649 650 return req; 651 } 652 653 void usb_request_free(struct usb_request *req) 654 { 655 free(req->private_data); 656 free(req); 657 } 658 659 int usb_request_queue(struct usb_request *req) 660 { 661 struct usbdevfs_urb *urb = (struct usbdevfs_urb*)req->private_data; 662 int res; 663 664 urb->status = -1; 665 urb->buffer = req->buffer; 666 // need to limit request size to avoid EINVAL 667 if (req->buffer_length > MAX_USBFS_BUFFER_SIZE) 668 urb->buffer_length = MAX_USBFS_BUFFER_SIZE; 669 else 670 urb->buffer_length = req->buffer_length; 671 672 do { 673 res = ioctl(req->dev->fd, USBDEVFS_SUBMITURB, urb); 674 } while((res < 0) && (errno == EINTR)); 675 676 return res; 677 } 678 679 struct usb_request *usb_request_wait(struct usb_device *dev) 680 { 681 struct usbdevfs_urb *urb = NULL; 682 struct usb_request *req = NULL; 683 684 while (1) { 685 int res = ioctl(dev->fd, USBDEVFS_REAPURB, &urb); 686 D("USBDEVFS_REAPURB returned %d\n", res); 687 if (res < 0) { 688 if(errno == EINTR) { 689 continue; 690 } 691 D("[ reap urb - error ]\n"); 692 return NULL; 693 } else { 694 D("[ urb @%p status = %d, actual = %d ]\n", 695 urb, urb->status, urb->actual_length); 696 req = (struct usb_request*)urb->usercontext; 697 req->actual_length = urb->actual_length; 698 } 699 break; 700 } 701 return req; 702 } 703 704 int usb_request_cancel(struct usb_request *req) 705 { 706 struct usbdevfs_urb *urb = ((struct usbdevfs_urb*)req->private_data); 707 return ioctl(req->dev->fd, USBDEVFS_DISCARDURB, urb); 708 } 709 710
