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 // From drivers/usb/core/devio.c 60 // I don't know why this isn't in a kernel header 61 #define MAX_USBFS_BUFFER_SIZE 16384 62 63 #define MAX_USBFS_WD_COUNT 10 64 65 struct usb_host_context { 66 int fd; 67 usb_device_added_cb cb_added; 68 usb_device_removed_cb cb_removed; 69 void *data; 70 int wds[MAX_USBFS_WD_COUNT]; 71 int wdd; 72 int wddbus; 73 }; 74 75 struct usb_device { 76 char dev_name[64]; 77 unsigned char desc[4096]; 78 int desc_length; 79 int fd; 80 int writeable; 81 }; 82 83 static inline int badname(const char *name) 84 { 85 while(*name) { 86 if(!isdigit(*name++)) return 1; 87 } 88 return 0; 89 } 90 91 static int find_existing_devices_bus(char *busname, 92 usb_device_added_cb added_cb, 93 void *client_data) 94 { 95 char devname[32]; 96 DIR *devdir; 97 struct dirent *de; 98 int done = 0; 99 100 devdir = opendir(busname); 101 if(devdir == 0) return 0; 102 103 while ((de = readdir(devdir)) && !done) { 104 if(badname(de->d_name)) continue; 105 106 snprintf(devname, sizeof(devname), "%s/%s", busname, de->d_name); 107 done = added_cb(devname, client_data); 108 } // end of devdir while 109 closedir(devdir); 110 111 return done; 112 } 113 114 /* returns true if one of the callbacks indicates we are done */ 115 static int find_existing_devices(usb_device_added_cb added_cb, 116 void *client_data) 117 { 118 char busname[32]; 119 DIR *busdir; 120 struct dirent *de; 121 int done = 0; 122 123 busdir = opendir(USB_FS_DIR); 124 if(busdir == 0) return 0; 125 126 while ((de = readdir(busdir)) != 0 && !done) { 127 if(badname(de->d_name)) continue; 128 129 snprintf(busname, sizeof(busname), USB_FS_DIR "/%s", de->d_name); 130 done = find_existing_devices_bus(busname, added_cb, 131 client_data); 132 } //end of busdir while 133 closedir(busdir); 134 135 return done; 136 } 137 138 static void watch_existing_subdirs(struct usb_host_context *context, 139 int *wds, int wd_count) 140 { 141 char path[100]; 142 int i, ret; 143 144 wds[0] = inotify_add_watch(context->fd, USB_FS_DIR, IN_CREATE | IN_DELETE); 145 if (wds[0] < 0) 146 return; 147 148 /* watch existing subdirectories of USB_FS_DIR */ 149 for (i = 1; i < wd_count; i++) { 150 snprintf(path, sizeof(path), USB_FS_DIR "/%03d", i); 151 ret = inotify_add_watch(context->fd, path, IN_CREATE | IN_DELETE); 152 if (ret >= 0) 153 wds[i] = ret; 154 } 155 } 156 157 struct usb_host_context *usb_host_init() 158 { 159 struct usb_host_context *context = calloc(1, sizeof(struct usb_host_context)); 160 if (!context) { 161 fprintf(stderr, "out of memory in usb_host_context\n"); 162 return NULL; 163 } 164 context->fd = inotify_init(); 165 if (context->fd < 0) { 166 fprintf(stderr, "inotify_init failed\n"); 167 free(context); 168 return NULL; 169 } 170 return context; 171 } 172 173 void usb_host_cleanup(struct usb_host_context *context) 174 { 175 close(context->fd); 176 free(context); 177 } 178 179 int usb_host_get_fd(struct usb_host_context *context) 180 { 181 return context->fd; 182 } /* usb_host_get_fd() */ 183 184 int usb_host_load(struct usb_host_context *context, 185 usb_device_added_cb added_cb, 186 usb_device_removed_cb removed_cb, 187 usb_discovery_done_cb discovery_done_cb, 188 void *client_data) 189 { 190 int done = 0; 191 int i; 192 193 context->cb_added = added_cb; 194 context->cb_removed = removed_cb; 195 context->data = client_data; 196 197 D("Created device discovery thread\n"); 198 199 /* watch for files added and deleted within USB_FS_DIR */ 200 context->wddbus = -1; 201 for (i = 0; i < MAX_USBFS_WD_COUNT; i++) 202 context->wds[i] = -1; 203 204 /* watch the root for new subdirectories */ 205 context->wdd = inotify_add_watch(context->fd, DEV_DIR, IN_CREATE | IN_DELETE); 206 if (context->wdd < 0) { 207 fprintf(stderr, "inotify_add_watch failed\n"); 208 if (discovery_done_cb) 209 discovery_done_cb(client_data); 210 return done; 211 } 212 213 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 214 215 /* check for existing devices first, after we have inotify set up */ 216 done = find_existing_devices(added_cb, client_data); 217 if (discovery_done_cb) 218 done |= discovery_done_cb(client_data); 219 220 return done; 221 } /* usb_host_load() */ 222 223 int usb_host_read_event(struct usb_host_context *context) 224 { 225 struct inotify_event* event; 226 char event_buf[512]; 227 char path[100]; 228 int i, ret, done = 0; 229 int offset = 0; 230 int wd; 231 232 ret = read(context->fd, event_buf, sizeof(event_buf)); 233 if (ret >= (int)sizeof(struct inotify_event)) { 234 while (offset < ret && !done) { 235 event = (struct inotify_event*)&event_buf[offset]; 236 done = 0; 237 wd = event->wd; 238 if (wd == context->wdd) { 239 if ((event->mask & IN_CREATE) && !strcmp(event->name, "bus")) { 240 context->wddbus = inotify_add_watch(context->fd, DEV_BUS_DIR, IN_CREATE | IN_DELETE); 241 if (context->wddbus < 0) { 242 done = 1; 243 } else { 244 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 245 done = find_existing_devices(context->cb_added, context->data); 246 } 247 } 248 } else if (wd == context->wddbus) { 249 if ((event->mask & IN_CREATE) && !strcmp(event->name, "usb")) { 250 watch_existing_subdirs(context, context->wds, MAX_USBFS_WD_COUNT); 251 done = find_existing_devices(context->cb_added, context->data); 252 } else if ((event->mask & IN_DELETE) && !strcmp(event->name, "usb")) { 253 for (i = 0; i < MAX_USBFS_WD_COUNT; i++) { 254 if (context->wds[i] >= 0) { 255 inotify_rm_watch(context->fd, context->wds[i]); 256 context->wds[i] = -1; 257 } 258 } 259 } 260 } else if (wd == context->wds[0]) { 261 i = atoi(event->name); 262 snprintf(path, sizeof(path), USB_FS_DIR "/%s", event->name); 263 D("%s subdirectory %s: index: %d\n", (event->mask & IN_CREATE) ? 264 "new" : "gone", path, i); 265 if (i > 0 && i < MAX_USBFS_WD_COUNT) { 266 if (event->mask & IN_CREATE) { 267 ret = inotify_add_watch(context->fd, path, 268 IN_CREATE | IN_DELETE); 269 if (ret >= 0) 270 context->wds[i] = ret; 271 done = find_existing_devices_bus(path, context->cb_added, 272 context->data); 273 } else if (event->mask & IN_DELETE) { 274 inotify_rm_watch(context->fd, context->wds[i]); 275 context->wds[i] = -1; 276 } 277 } 278 } else { 279 for (i = 1; (i < MAX_USBFS_WD_COUNT) && !done; i++) { 280 if (wd == context->wds[i]) { 281 snprintf(path, sizeof(path), USB_FS_DIR "/%03d/%s", i, event->name); 282 if (event->mask == IN_CREATE) { 283 D("new device %s\n", path); 284 done = context->cb_added(path, context->data); 285 } else if (event->mask == IN_DELETE) { 286 D("gone device %s\n", path); 287 done = context->cb_removed(path, context->data); 288 } 289 } 290 } 291 } 292 293 offset += sizeof(struct inotify_event) + event->len; 294 } 295 } 296 297 return done; 298 } /* usb_host_read_event() */ 299 300 void usb_host_run(struct usb_host_context *context, 301 usb_device_added_cb added_cb, 302 usb_device_removed_cb removed_cb, 303 usb_discovery_done_cb discovery_done_cb, 304 void *client_data) 305 { 306 int done; 307 308 done = usb_host_load(context, added_cb, removed_cb, discovery_done_cb, client_data); 309 310 while (!done) { 311 312 done = usb_host_read_event(context); 313 } 314 } /* usb_host_run() */ 315 316 struct usb_device *usb_device_open(const char *dev_name) 317 { 318 int fd, did_retry = 0, writeable = 1; 319 320 D("usb_device_open %s\n", dev_name); 321 322 retry: 323 fd = open(dev_name, O_RDWR); 324 if (fd < 0) { 325 /* if we fail, see if have read-only access */ 326 fd = open(dev_name, O_RDONLY); 327 D("usb_device_open open returned %d errno %d\n", fd, errno); 328 if (fd < 0 && (errno == EACCES || errno == ENOENT) && !did_retry) { 329 /* work around race condition between inotify and permissions management */ 330 sleep(1); 331 did_retry = 1; 332 goto retry; 333 } 334 335 if (fd < 0) 336 return NULL; 337 writeable = 0; 338 D("[ usb open read-only %s fd = %d]\n", dev_name, fd); 339 } 340 341 struct usb_device* result = usb_device_new(dev_name, fd); 342 if (result) 343 result->writeable = writeable; 344 return result; 345 } 346 347 void usb_device_close(struct usb_device *device) 348 { 349 close(device->fd); 350 free(device); 351 } 352 353 struct usb_device *usb_device_new(const char *dev_name, int fd) 354 { 355 struct usb_device *device = calloc(1, sizeof(struct usb_device)); 356 int length; 357 358 D("usb_device_new %s fd: %d\n", dev_name, fd); 359 360 if (lseek(fd, 0, SEEK_SET) != 0) 361 goto failed; 362 length = read(fd, device->desc, sizeof(device->desc)); 363 D("usb_device_new read returned %d errno %d\n", length, errno); 364 if (length < 0) 365 goto failed; 366 367 strncpy(device->dev_name, dev_name, sizeof(device->dev_name) - 1); 368 device->fd = fd; 369 device->desc_length = length; 370 // assume we are writeable, since usb_device_get_fd will only return writeable fds 371 device->writeable = 1; 372 return device; 373 374 failed: 375 close(fd); 376 free(device); 377 return NULL; 378 } 379 380 static int usb_device_reopen_writeable(struct usb_device *device) 381 { 382 if (device->writeable) 383 return 1; 384 385 int fd = open(device->dev_name, O_RDWR); 386 if (fd >= 0) { 387 close(device->fd); 388 device->fd = fd; 389 device->writeable = 1; 390 return 1; 391 } 392 D("usb_device_reopen_writeable failed errno %d\n", errno); 393 return 0; 394 } 395 396 int usb_device_get_fd(struct usb_device *device) 397 { 398 if (!usb_device_reopen_writeable(device)) 399 return -1; 400 return device->fd; 401 } 402 403 const char* usb_device_get_name(struct usb_device *device) 404 { 405 return device->dev_name; 406 } 407 408 int usb_device_get_unique_id(struct usb_device *device) 409 { 410 int bus = 0, dev = 0; 411 sscanf(device->dev_name, USB_FS_ID_SCANNER, &bus, &dev); 412 return bus * 1000 + dev; 413 } 414 415 int usb_device_get_unique_id_from_name(const char* name) 416 { 417 int bus = 0, dev = 0; 418 sscanf(name, USB_FS_ID_SCANNER, &bus, &dev); 419 return bus * 1000 + dev; 420 } 421 422 char* usb_device_get_name_from_unique_id(int id) 423 { 424 int bus = id / 1000; 425 int dev = id % 1000; 426 char* result = (char *)calloc(1, strlen(USB_FS_ID_FORMAT)); 427 snprintf(result, strlen(USB_FS_ID_FORMAT) - 1, USB_FS_ID_FORMAT, bus, dev); 428 return result; 429 } 430 431 uint16_t usb_device_get_vendor_id(struct usb_device *device) 432 { 433 struct usb_device_descriptor* desc = (struct usb_device_descriptor*)device->desc; 434 return __le16_to_cpu(desc->idVendor); 435 } 436 437 uint16_t usb_device_get_product_id(struct usb_device *device) 438 { 439 struct usb_device_descriptor* desc = (struct usb_device_descriptor*)device->desc; 440 return __le16_to_cpu(desc->idProduct); 441 } 442 443 const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device) 444 { 445 return (struct usb_device_descriptor*)device->desc; 446 } 447 448 char* usb_device_get_string(struct usb_device *device, int id) 449 { 450 char string[256]; 451 __u16 buffer[128]; 452 __u16 languages[128]; 453 int i, result; 454 int languageCount = 0; 455 456 string[0] = 0; 457 memset(languages, 0, sizeof(languages)); 458 459 // read list of supported languages 460 result = usb_device_control_transfer(device, 461 USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE, USB_REQ_GET_DESCRIPTOR, 462 (USB_DT_STRING << 8) | 0, 0, languages, sizeof(languages), 0); 463 if (result > 0) 464 languageCount = (result - 2) / 2; 465 466 for (i = 1; i <= languageCount; i++) { 467 memset(buffer, 0, sizeof(buffer)); 468 469 result = usb_device_control_transfer(device, 470 USB_DIR_IN|USB_TYPE_STANDARD|USB_RECIP_DEVICE, USB_REQ_GET_DESCRIPTOR, 471 (USB_DT_STRING << 8) | id, languages[i], buffer, sizeof(buffer), 0); 472 if (result > 0) { 473 int i; 474 // skip first word, and copy the rest to the string, changing shorts to bytes. 475 result /= 2; 476 for (i = 1; i < result; i++) 477 string[i - 1] = buffer[i]; 478 string[i - 1] = 0; 479 return strdup(string); 480 } 481 } 482 483 return NULL; 484 } 485 486 char* usb_device_get_manufacturer_name(struct usb_device *device) 487 { 488 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 489 490 if (desc->iManufacturer) 491 return usb_device_get_string(device, desc->iManufacturer); 492 else 493 return NULL; 494 } 495 496 char* usb_device_get_product_name(struct usb_device *device) 497 { 498 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 499 500 if (desc->iProduct) 501 return usb_device_get_string(device, desc->iProduct); 502 else 503 return NULL; 504 } 505 506 char* usb_device_get_serial(struct usb_device *device) 507 { 508 struct usb_device_descriptor *desc = (struct usb_device_descriptor *)device->desc; 509 510 if (desc->iSerialNumber) 511 return usb_device_get_string(device, desc->iSerialNumber); 512 else 513 return NULL; 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_control_transfer(struct usb_device *device, 560 int requestType, 561 int request, 562 int value, 563 int index, 564 void* buffer, 565 int length, 566 unsigned int timeout) 567 { 568 struct usbdevfs_ctrltransfer ctrl; 569 570 // this usually requires read/write permission 571 if (!usb_device_reopen_writeable(device)) 572 return -1; 573 574 memset(&ctrl, 0, sizeof(ctrl)); 575 ctrl.bRequestType = requestType; 576 ctrl.bRequest = request; 577 ctrl.wValue = value; 578 ctrl.wIndex = index; 579 ctrl.wLength = length; 580 ctrl.data = buffer; 581 ctrl.timeout = timeout; 582 return ioctl(device->fd, USBDEVFS_CONTROL, &ctrl); 583 } 584 585 int usb_device_bulk_transfer(struct usb_device *device, 586 int endpoint, 587 void* buffer, 588 int length, 589 unsigned int timeout) 590 { 591 struct usbdevfs_bulktransfer ctrl; 592 593 // need to limit request size to avoid EINVAL 594 if (length > MAX_USBFS_BUFFER_SIZE) 595 length = MAX_USBFS_BUFFER_SIZE; 596 597 memset(&ctrl, 0, sizeof(ctrl)); 598 ctrl.ep = endpoint; 599 ctrl.len = length; 600 ctrl.data = buffer; 601 ctrl.timeout = timeout; 602 return ioctl(device->fd, USBDEVFS_BULK, &ctrl); 603 } 604 605 struct usb_request *usb_request_new(struct usb_device *dev, 606 const struct usb_endpoint_descriptor *ep_desc) 607 { 608 struct usbdevfs_urb *urb = calloc(1, sizeof(struct usbdevfs_urb)); 609 if (!urb) 610 return NULL; 611 612 if ((ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_BULK) 613 urb->type = USBDEVFS_URB_TYPE_BULK; 614 else if ((ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT) 615 urb->type = USBDEVFS_URB_TYPE_INTERRUPT; 616 else { 617 D("Unsupported endpoint type %d", ep_desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK); 618 free(urb); 619 return NULL; 620 } 621 urb->endpoint = ep_desc->bEndpointAddress; 622 623 struct usb_request *req = calloc(1, sizeof(struct usb_request)); 624 if (!req) { 625 free(urb); 626 return NULL; 627 } 628 629 req->dev = dev; 630 req->max_packet_size = __le16_to_cpu(ep_desc->wMaxPacketSize); 631 req->private_data = urb; 632 req->endpoint = urb->endpoint; 633 urb->usercontext = req; 634 635 return req; 636 } 637 638 void usb_request_free(struct usb_request *req) 639 { 640 free(req->private_data); 641 free(req); 642 } 643 644 int usb_request_queue(struct usb_request *req) 645 { 646 struct usbdevfs_urb *urb = (struct usbdevfs_urb*)req->private_data; 647 int res; 648 649 urb->status = -1; 650 urb->buffer = req->buffer; 651 // need to limit request size to avoid EINVAL 652 if (req->buffer_length > MAX_USBFS_BUFFER_SIZE) 653 urb->buffer_length = MAX_USBFS_BUFFER_SIZE; 654 else 655 urb->buffer_length = req->buffer_length; 656 657 do { 658 res = ioctl(req->dev->fd, USBDEVFS_SUBMITURB, urb); 659 } while((res < 0) && (errno == EINTR)); 660 661 return res; 662 } 663 664 struct usb_request *usb_request_wait(struct usb_device *dev) 665 { 666 struct usbdevfs_urb *urb = NULL; 667 struct usb_request *req = NULL; 668 669 while (1) { 670 int res = ioctl(dev->fd, USBDEVFS_REAPURB, &urb); 671 D("USBDEVFS_REAPURB returned %d\n", res); 672 if (res < 0) { 673 if(errno == EINTR) { 674 continue; 675 } 676 D("[ reap urb - error ]\n"); 677 return NULL; 678 } else { 679 D("[ urb @%p status = %d, actual = %d ]\n", 680 urb, urb->status, urb->actual_length); 681 req = (struct usb_request*)urb->usercontext; 682 req->actual_length = urb->actual_length; 683 } 684 break; 685 } 686 return req; 687 } 688 689 int usb_request_cancel(struct usb_request *req) 690 { 691 struct usbdevfs_urb *urb = ((struct usbdevfs_urb*)req->private_data); 692 return ioctl(req->dev->fd, USBDEVFS_DISCARDURB, &urb); 693 } 694 695
