1/* 2 * Gadget Function Driver for Android USB accessories 3 * 4 * Copyright (C) 2011 Google, Inc. 5 * Author: Mike Lockwood <lockwood@android.com> 6 * 7 * This software is licensed under the terms of the GNU General Public 8 * License version 2, as published by the Free Software Foundation, and 9 * may be copied, distributed, and modified under those terms. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 */ 17 18/* #define DEBUG */ 19/* #define VERBOSE_DEBUG */ 20 21#include <linux/module.h> 22#include <linux/init.h> 23#include <linux/poll.h> 24#include <linux/delay.h> 25#include <linux/wait.h> 26#include <linux/err.h> 27#include <linux/interrupt.h> 28#include <linux/kthread.h> 29#include <linux/freezer.h> 30 31#include <linux/types.h> 32#include <linux/file.h> 33#include <linux/device.h> 34#include <linux/miscdevice.h> 35 36#include <linux/usb.h> 37#include <linux/usb/ch9.h> 38#include <linux/usb/f_accessory.h> 39 40#define BULK_BUFFER_SIZE 16384 41#define ACC_STRING_SIZE 256 42 43#define PROTOCOL_VERSION 1 44 45/* String IDs */ 46#define INTERFACE_STRING_INDEX 0 47 48/* number of tx and rx requests to allocate */ 49#define TX_REQ_MAX 4 50#define RX_REQ_MAX 2 51 52struct acc_dev { 53 struct usb_function function; 54 struct usb_composite_dev *cdev; 55 spinlock_t lock; 56 57 struct usb_ep *ep_in; 58 struct usb_ep *ep_out; 59 60 /* set to 1 when we connect */ 61 int online:1; 62 /* Set to 1 when we disconnect. 63 * Not cleared until our file is closed. 64 */ 65 int disconnected:1; 66 67 /* strings sent by the host */ 68 char manufacturer[ACC_STRING_SIZE]; 69 char model[ACC_STRING_SIZE]; 70 char description[ACC_STRING_SIZE]; 71 char version[ACC_STRING_SIZE]; 72 char uri[ACC_STRING_SIZE]; 73 char serial[ACC_STRING_SIZE]; 74 75 /* for acc_complete_set_string */ 76 int string_index; 77 78 /* set to 1 if we have a pending start request */ 79 int start_requested; 80 81 /* synchronize access to our device file */ 82 atomic_t open_excl; 83 84 struct list_head tx_idle; 85 86 wait_queue_head_t read_wq; 87 wait_queue_head_t write_wq; 88 struct usb_request *rx_req[RX_REQ_MAX]; 89 int rx_done; 90 struct delayed_work work; 91}; 92 93static struct usb_interface_descriptor acc_interface_desc = { 94 .bLength = USB_DT_INTERFACE_SIZE, 95 .bDescriptorType = USB_DT_INTERFACE, 96 .bInterfaceNumber = 0, 97 .bNumEndpoints = 2, 98 .bInterfaceClass = USB_CLASS_VENDOR_SPEC, 99 .bInterfaceSubClass = USB_SUBCLASS_VENDOR_SPEC, 100 .bInterfaceProtocol = 0, 101}; 102 103static struct usb_endpoint_descriptor acc_highspeed_in_desc = { 104 .bLength = USB_DT_ENDPOINT_SIZE, 105 .bDescriptorType = USB_DT_ENDPOINT, 106 .bEndpointAddress = USB_DIR_IN, 107 .bmAttributes = USB_ENDPOINT_XFER_BULK, 108 .wMaxPacketSize = __constant_cpu_to_le16(512), 109}; 110 111static struct usb_endpoint_descriptor acc_highspeed_out_desc = { 112 .bLength = USB_DT_ENDPOINT_SIZE, 113 .bDescriptorType = USB_DT_ENDPOINT, 114 .bEndpointAddress = USB_DIR_OUT, 115 .bmAttributes = USB_ENDPOINT_XFER_BULK, 116 .wMaxPacketSize = __constant_cpu_to_le16(512), 117}; 118 119static struct usb_endpoint_descriptor acc_fullspeed_in_desc = { 120 .bLength = USB_DT_ENDPOINT_SIZE, 121 .bDescriptorType = USB_DT_ENDPOINT, 122 .bEndpointAddress = USB_DIR_IN, 123 .bmAttributes = USB_ENDPOINT_XFER_BULK, 124}; 125 126static struct usb_endpoint_descriptor acc_fullspeed_out_desc = { 127 .bLength = USB_DT_ENDPOINT_SIZE, 128 .bDescriptorType = USB_DT_ENDPOINT, 129 .bEndpointAddress = USB_DIR_OUT, 130 .bmAttributes = USB_ENDPOINT_XFER_BULK, 131}; 132 133static struct usb_descriptor_header *fs_acc_descs[] = { 134 (struct usb_descriptor_header *) &acc_interface_desc, 135 (struct usb_descriptor_header *) &acc_fullspeed_in_desc, 136 (struct usb_descriptor_header *) &acc_fullspeed_out_desc, 137 NULL, 138}; 139 140static struct usb_descriptor_header *hs_acc_descs[] = { 141 (struct usb_descriptor_header *) &acc_interface_desc, 142 (struct usb_descriptor_header *) &acc_highspeed_in_desc, 143 (struct usb_descriptor_header *) &acc_highspeed_out_desc, 144 NULL, 145}; 146 147static struct usb_string acc_string_defs[] = { 148 [INTERFACE_STRING_INDEX].s = "Android Accessory Interface", 149 { }, /* end of list */ 150}; 151 152static struct usb_gadget_strings acc_string_table = { 153 .language = 0x0409, /* en-US */ 154 .strings = acc_string_defs, 155}; 156 157static struct usb_gadget_strings *acc_strings[] = { 158 &acc_string_table, 159 NULL, 160}; 161 162/* temporary variable used between acc_open() and acc_gadget_bind() */ 163static struct acc_dev *_acc_dev; 164 165static inline struct acc_dev *func_to_dev(struct usb_function *f) 166{ 167 return container_of(f, struct acc_dev, function); 168} 169 170static struct usb_request *acc_request_new(struct usb_ep *ep, int buffer_size) 171{ 172 struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL); 173 if (!req) 174 return NULL; 175 176 /* now allocate buffers for the requests */ 177 req->buf = kmalloc(buffer_size, GFP_KERNEL); 178 if (!req->buf) { 179 usb_ep_free_request(ep, req); 180 return NULL; 181 } 182 183 return req; 184} 185 186static void acc_request_free(struct usb_request *req, struct usb_ep *ep) 187{ 188 if (req) { 189 kfree(req->buf); 190 usb_ep_free_request(ep, req); 191 } 192} 193 194/* add a request to the tail of a list */ 195static void req_put(struct acc_dev *dev, struct list_head *head, 196 struct usb_request *req) 197{ 198 unsigned long flags; 199 200 spin_lock_irqsave(&dev->lock, flags); 201 list_add_tail(&req->list, head); 202 spin_unlock_irqrestore(&dev->lock, flags); 203} 204 205/* remove a request from the head of a list */ 206static struct usb_request *req_get(struct acc_dev *dev, struct list_head *head) 207{ 208 unsigned long flags; 209 struct usb_request *req; 210 211 spin_lock_irqsave(&dev->lock, flags); 212 if (list_empty(head)) { 213 req = 0; 214 } else { 215 req = list_first_entry(head, struct usb_request, list); 216 list_del(&req->list); 217 } 218 spin_unlock_irqrestore(&dev->lock, flags); 219 return req; 220} 221 222static void acc_set_disconnected(struct acc_dev *dev) 223{ 224 dev->online = 0; 225 dev->disconnected = 1; 226} 227 228static void acc_complete_in(struct usb_ep *ep, struct usb_request *req) 229{ 230 struct acc_dev *dev = _acc_dev; 231 232 if (req->status != 0) 233 acc_set_disconnected(dev); 234 235 req_put(dev, &dev->tx_idle, req); 236 237 wake_up(&dev->write_wq); 238} 239 240static void acc_complete_out(struct usb_ep *ep, struct usb_request *req) 241{ 242 struct acc_dev *dev = _acc_dev; 243 244 dev->rx_done = 1; 245 if (req->status != 0) 246 acc_set_disconnected(dev); 247 248 wake_up(&dev->read_wq); 249} 250 251static void acc_complete_set_string(struct usb_ep *ep, struct usb_request *req) 252{ 253 struct acc_dev *dev = ep->driver_data; 254 char *string_dest = NULL; 255 int length = req->actual; 256 257 if (req->status != 0) { 258 pr_err("acc_complete_set_string, err %d\n", req->status); 259 return; 260 } 261 262 switch (dev->string_index) { 263 case ACCESSORY_STRING_MANUFACTURER: 264 string_dest = dev->manufacturer; 265 break; 266 case ACCESSORY_STRING_MODEL: 267 string_dest = dev->model; 268 break; 269 case ACCESSORY_STRING_DESCRIPTION: 270 string_dest = dev->description; 271 break; 272 case ACCESSORY_STRING_VERSION: 273 string_dest = dev->version; 274 break; 275 case ACCESSORY_STRING_URI: 276 string_dest = dev->uri; 277 break; 278 case ACCESSORY_STRING_SERIAL: 279 string_dest = dev->serial; 280 break; 281 } 282 if (string_dest) { 283 unsigned long flags; 284 285 if (length >= ACC_STRING_SIZE) 286 length = ACC_STRING_SIZE - 1; 287 288 spin_lock_irqsave(&dev->lock, flags); 289 memcpy(string_dest, req->buf, length); 290 /* ensure zero termination */ 291 string_dest[length] = 0; 292 spin_unlock_irqrestore(&dev->lock, flags); 293 } else { 294 pr_err("unknown accessory string index %d\n", 295 dev->string_index); 296 } 297} 298 299static int __init create_bulk_endpoints(struct acc_dev *dev, 300 struct usb_endpoint_descriptor *in_desc, 301 struct usb_endpoint_descriptor *out_desc) 302{ 303 struct usb_composite_dev *cdev = dev->cdev; 304 struct usb_request *req; 305 struct usb_ep *ep; 306 int i; 307 308 DBG(cdev, "create_bulk_endpoints dev: %p\n", dev); 309 310 ep = usb_ep_autoconfig(cdev->gadget, in_desc); 311 if (!ep) { 312 DBG(cdev, "usb_ep_autoconfig for ep_in failed\n"); 313 return -ENODEV; 314 } 315 DBG(cdev, "usb_ep_autoconfig for ep_in got %s\n", ep->name); 316 ep->driver_data = dev; /* claim the endpoint */ 317 dev->ep_in = ep; 318 319 ep = usb_ep_autoconfig(cdev->gadget, out_desc); 320 if (!ep) { 321 DBG(cdev, "usb_ep_autoconfig for ep_out failed\n"); 322 return -ENODEV; 323 } 324 DBG(cdev, "usb_ep_autoconfig for ep_out got %s\n", ep->name); 325 ep->driver_data = dev; /* claim the endpoint */ 326 dev->ep_out = ep; 327 328 ep = usb_ep_autoconfig(cdev->gadget, out_desc); 329 if (!ep) { 330 DBG(cdev, "usb_ep_autoconfig for ep_out failed\n"); 331 return -ENODEV; 332 } 333 DBG(cdev, "usb_ep_autoconfig for ep_out got %s\n", ep->name); 334 ep->driver_data = dev; /* claim the endpoint */ 335 dev->ep_out = ep; 336 337 /* now allocate requests for our endpoints */ 338 for (i = 0; i < TX_REQ_MAX; i++) { 339 req = acc_request_new(dev->ep_in, BULK_BUFFER_SIZE); 340 if (!req) 341 goto fail; 342 req->complete = acc_complete_in; 343 req_put(dev, &dev->tx_idle, req); 344 } 345 for (i = 0; i < RX_REQ_MAX; i++) { 346 req = acc_request_new(dev->ep_out, BULK_BUFFER_SIZE); 347 if (!req) 348 goto fail; 349 req->complete = acc_complete_out; 350 dev->rx_req[i] = req; 351 } 352 353 return 0; 354 355fail: 356 printk(KERN_ERR "acc_bind() could not allocate requests\n"); 357 while ((req = req_get(dev, &dev->tx_idle))) 358 acc_request_free(req, dev->ep_in); 359 for (i = 0; i < RX_REQ_MAX; i++) 360 acc_request_free(dev->rx_req[i], dev->ep_out); 361 return -1; 362} 363 364static ssize_t acc_read(struct file *fp, char __user *buf, 365 size_t count, loff_t *pos) 366{ 367 struct acc_dev *dev = fp->private_data; 368 struct usb_request *req; 369 int r = count, xfer; 370 int ret = 0; 371 372 pr_debug("acc_read(%d)\n", count); 373 374 if (dev->disconnected) 375 return -ENODEV; 376 377 if (count > BULK_BUFFER_SIZE) 378 count = BULK_BUFFER_SIZE; 379 380 /* we will block until we're online */ 381 pr_debug("acc_read: waiting for online\n"); 382 ret = wait_event_interruptible(dev->read_wq, dev->online); 383 if (ret < 0) { 384 r = ret; 385 goto done; 386 } 387 388requeue_req: 389 /* queue a request */ 390 req = dev->rx_req[0]; 391 req->length = count; 392 dev->rx_done = 0; 393 ret = usb_ep_queue(dev->ep_out, req, GFP_KERNEL); 394 if (ret < 0) { 395 r = -EIO; 396 goto done; 397 } else { 398 pr_debug("rx %p queue\n", req); 399 } 400 401 /* wait for a request to complete */ 402 ret = wait_event_interruptible(dev->read_wq, dev->rx_done); 403 if (ret < 0) { 404 r = ret; 405 usb_ep_dequeue(dev->ep_out, req); 406 goto done; 407 } 408 if (dev->online) { 409 /* If we got a 0-len packet, throw it back and try again. */ 410 if (req->actual == 0) 411 goto requeue_req; 412 413 pr_debug("rx %p %d\n", req, req->actual); 414 xfer = (req->actual < count) ? req->actual : count; 415 r = xfer; 416 if (copy_to_user(buf, req->buf, xfer)) 417 r = -EFAULT; 418 } else 419 r = -EIO; 420 421done: 422 pr_debug("acc_read returning %d\n", r); 423 return r; 424} 425 426static ssize_t acc_write(struct file *fp, const char __user *buf, 427 size_t count, loff_t *pos) 428{ 429 struct acc_dev *dev = fp->private_data; 430 struct usb_request *req = 0; 431 int r = count, xfer; 432 int ret; 433 434 pr_debug("acc_write(%d)\n", count); 435 436 if (!dev->online || dev->disconnected) 437 return -ENODEV; 438 439 while (count > 0) { 440 if (!dev->online) { 441 pr_debug("acc_write dev->error\n"); 442 r = -EIO; 443 break; 444 } 445 446 /* get an idle tx request to use */ 447 req = 0; 448 ret = wait_event_interruptible(dev->write_wq, 449 ((req = req_get(dev, &dev->tx_idle)) || !dev->online)); 450 if (!req) { 451 r = ret; 452 break; 453 } 454 455 if (count > BULK_BUFFER_SIZE) 456 xfer = BULK_BUFFER_SIZE; 457 else 458 xfer = count; 459 if (copy_from_user(req->buf, buf, xfer)) { 460 r = -EFAULT; 461 break; 462 } 463 464 req->length = xfer; 465 ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL); 466 if (ret < 0) { 467 pr_debug("acc_write: xfer error %d\n", ret); 468 r = -EIO; 469 break; 470 } 471 472 buf += xfer; 473 count -= xfer; 474 475 /* zero this so we don't try to free it on error exit */ 476 req = 0; 477 } 478 479 if (req) 480 req_put(dev, &dev->tx_idle, req); 481 482 pr_debug("acc_write returning %d\n", r); 483 return r; 484} 485 486static long acc_ioctl(struct file *fp, unsigned code, unsigned long value) 487{ 488 struct acc_dev *dev = fp->private_data; 489 char *src = NULL; 490 int ret; 491 492 switch (code) { 493 case ACCESSORY_GET_STRING_MANUFACTURER: 494 src = dev->manufacturer; 495 break; 496 case ACCESSORY_GET_STRING_MODEL: 497 src = dev->model; 498 break; 499 case ACCESSORY_GET_STRING_DESCRIPTION: 500 src = dev->description; 501 break; 502 case ACCESSORY_GET_STRING_VERSION: 503 src = dev->version; 504 break; 505 case ACCESSORY_GET_STRING_URI: 506 src = dev->uri; 507 break; 508 case ACCESSORY_GET_STRING_SERIAL: 509 src = dev->serial; 510 break; 511 case ACCESSORY_IS_START_REQUESTED: 512 return dev->start_requested; 513 } 514 if (!src) 515 return -EINVAL; 516 517 ret = strlen(src) + 1; 518 if (copy_to_user((void __user *)value, src, ret)) 519 ret = -EFAULT; 520 return ret; 521} 522 523static int acc_open(struct inode *ip, struct file *fp) 524{ 525 printk(KERN_INFO "acc_open\n"); 526 if (atomic_xchg(&_acc_dev->open_excl, 1)) 527 return -EBUSY; 528 529 _acc_dev->disconnected = 0; 530 fp->private_data = _acc_dev; 531 return 0; 532} 533 534static int acc_release(struct inode *ip, struct file *fp) 535{ 536 printk(KERN_INFO "acc_release\n"); 537 538 WARN_ON(!atomic_xchg(&_acc_dev->open_excl, 0)); 539 _acc_dev->disconnected = 0; 540 return 0; 541} 542 543/* file operations for /dev/acc_usb */ 544static const struct file_operations acc_fops = { 545 .owner = THIS_MODULE, 546 .read = acc_read, 547 .write = acc_write, 548 .unlocked_ioctl = acc_ioctl, 549 .open = acc_open, 550 .release = acc_release, 551}; 552 553static struct miscdevice acc_device = { 554 .minor = MISC_DYNAMIC_MINOR, 555 .name = "usb_accessory", 556 .fops = &acc_fops, 557}; 558 559 560static int acc_ctrlrequest(struct usb_composite_dev *cdev, 561 const struct usb_ctrlrequest *ctrl) 562{ 563 struct acc_dev *dev = _acc_dev; 564 int value = -EOPNOTSUPP; 565 u8 b_requestType = ctrl->bRequestType; 566 u8 b_request = ctrl->bRequest; 567 u16 w_index = le16_to_cpu(ctrl->wIndex); 568 u16 w_value = le16_to_cpu(ctrl->wValue); 569 u16 w_length = le16_to_cpu(ctrl->wLength); 570 571/* 572 printk(KERN_INFO "acc_ctrlrequest " 573 "%02x.%02x v%04x i%04x l%u\n", 574 b_requestType, b_request, 575 w_value, w_index, w_length); 576*/ 577 578 if (b_requestType == (USB_DIR_OUT | USB_TYPE_VENDOR)) { 579 if (b_request == ACCESSORY_START) { 580 dev->start_requested = 1; 581 schedule_delayed_work( 582 &dev->work, msecs_to_jiffies(10)); 583 value = 0; 584 } else if (b_request == ACCESSORY_SEND_STRING) { 585 dev->string_index = w_index; 586 cdev->gadget->ep0->driver_data = dev; 587 cdev->req->complete = acc_complete_set_string; 588 value = w_length; 589 } 590 } else if (b_requestType == (USB_DIR_IN | USB_TYPE_VENDOR)) { 591 if (b_request == ACCESSORY_GET_PROTOCOL) { 592 *((u16 *)cdev->req->buf) = PROTOCOL_VERSION; 593 value = sizeof(u16); 594 595 /* clear any string left over from a previous session */ 596 memset(dev->manufacturer, 0, sizeof(dev->manufacturer)); 597 memset(dev->model, 0, sizeof(dev->model)); 598 memset(dev->description, 0, sizeof(dev->description)); 599 memset(dev->version, 0, sizeof(dev->version)); 600 memset(dev->uri, 0, sizeof(dev->uri)); 601 memset(dev->serial, 0, sizeof(dev->serial)); 602 dev->start_requested = 0; 603 } 604 } 605 606 if (value >= 0) { 607 cdev->req->zero = 0; 608 cdev->req->length = value; 609 value = usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC); 610 if (value < 0) 611 ERROR(cdev, "%s setup response queue error\n", 612 __func__); 613 } 614 615 if (value == -EOPNOTSUPP) 616 VDBG(cdev, 617 "unknown class-specific control req " 618 "%02x.%02x v%04x i%04x l%u\n", 619 ctrl->bRequestType, ctrl->bRequest, 620 w_value, w_index, w_length); 621 return value; 622} 623 624static int 625acc_function_bind(struct usb_configuration *c, struct usb_function *f) 626{ 627 struct usb_composite_dev *cdev = c->cdev; 628 struct acc_dev *dev = func_to_dev(f); 629 int id; 630 int ret; 631 632 DBG(cdev, "acc_function_bind dev: %p\n", dev); 633 634 dev->start_requested = 0; 635 636 /* allocate interface ID(s) */ 637 id = usb_interface_id(c, f); 638 if (id < 0) 639 return id; 640 acc_interface_desc.bInterfaceNumber = id; 641 642 /* allocate endpoints */ 643 ret = create_bulk_endpoints(dev, &acc_fullspeed_in_desc, 644 &acc_fullspeed_out_desc); 645 if (ret) 646 return ret; 647 648 /* support high speed hardware */ 649 if (gadget_is_dualspeed(c->cdev->gadget)) { 650 acc_highspeed_in_desc.bEndpointAddress = 651 acc_fullspeed_in_desc.bEndpointAddress; 652 acc_highspeed_out_desc.bEndpointAddress = 653 acc_fullspeed_out_desc.bEndpointAddress; 654 } 655 656 DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n", 657 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", 658 f->name, dev->ep_in->name, dev->ep_out->name); 659 return 0; 660} 661 662static void 663acc_function_unbind(struct usb_configuration *c, struct usb_function *f) 664{ 665 struct acc_dev *dev = func_to_dev(f); 666 struct usb_request *req; 667 int i; 668 669 while ((req = req_get(dev, &dev->tx_idle))) 670 acc_request_free(req, dev->ep_in); 671 for (i = 0; i < RX_REQ_MAX; i++) 672 acc_request_free(dev->rx_req[i], dev->ep_out); 673} 674 675static void acc_work(struct work_struct *data) 676{ 677 char *envp[2] = { "ACCESSORY=START", NULL }; 678 kobject_uevent_env(&acc_device.this_device->kobj, KOBJ_CHANGE, envp); 679} 680 681static int acc_function_set_alt(struct usb_function *f, 682 unsigned intf, unsigned alt) 683{ 684 struct acc_dev *dev = func_to_dev(f); 685 struct usb_composite_dev *cdev = f->config->cdev; 686 int ret; 687 688 DBG(cdev, "acc_function_set_alt intf: %d alt: %d\n", intf, alt); 689 690 ret = config_ep_by_speed(cdev->gadget, f, dev->ep_in); 691 if (ret) 692 return ret; 693 694 ret = usb_ep_enable(dev->ep_in); 695 if (ret) 696 return ret; 697 698 ret = config_ep_by_speed(cdev->gadget, f, dev->ep_out); 699 if (ret) 700 return ret; 701 702 ret = usb_ep_enable(dev->ep_out); 703 if (ret) { 704 usb_ep_disable(dev->ep_in); 705 return ret; 706 } 707 708 dev->online = 1; 709 710 /* readers may be blocked waiting for us to go online */ 711 wake_up(&dev->read_wq); 712 return 0; 713} 714 715static void acc_function_disable(struct usb_function *f) 716{ 717 struct acc_dev *dev = func_to_dev(f); 718 struct usb_composite_dev *cdev = dev->cdev; 719 720 DBG(cdev, "acc_function_disable\n"); 721 acc_set_disconnected(dev); 722 usb_ep_disable(dev->ep_in); 723 usb_ep_disable(dev->ep_out); 724 725 /* readers may be blocked waiting for us to go online */ 726 wake_up(&dev->read_wq); 727 728 VDBG(cdev, "%s disabled\n", dev->function.name); 729} 730 731static int acc_bind_config(struct usb_configuration *c) 732{ 733 struct acc_dev *dev = _acc_dev; 734 int ret; 735 736 printk(KERN_INFO "acc_bind_config\n"); 737 738 /* allocate a string ID for our interface */ 739 if (acc_string_defs[INTERFACE_STRING_INDEX].id == 0) { 740 ret = usb_string_id(c->cdev); 741 if (ret < 0) 742 return ret; 743 acc_string_defs[INTERFACE_STRING_INDEX].id = ret; 744 acc_interface_desc.iInterface = ret; 745 } 746 747 dev->cdev = c->cdev; 748 dev->function.name = "accessory"; 749 dev->function.strings = acc_strings, 750 dev->function.descriptors = fs_acc_descs; 751 dev->function.hs_descriptors = hs_acc_descs; 752 dev->function.bind = acc_function_bind; 753 dev->function.unbind = acc_function_unbind; 754 dev->function.set_alt = acc_function_set_alt; 755 dev->function.disable = acc_function_disable; 756 757 return usb_add_function(c, &dev->function); 758} 759 760static int acc_setup(void) 761{ 762 struct acc_dev *dev; 763 int ret; 764 765 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 766 if (!dev) 767 return -ENOMEM; 768 769 spin_lock_init(&dev->lock); 770 init_waitqueue_head(&dev->read_wq); 771 init_waitqueue_head(&dev->write_wq); 772 atomic_set(&dev->open_excl, 0); 773 INIT_LIST_HEAD(&dev->tx_idle); 774 INIT_DELAYED_WORK(&dev->work, acc_work); 775 776 /* _acc_dev must be set before calling usb_gadget_register_driver */ 777 _acc_dev = dev; 778 779 ret = misc_register(&acc_device); 780 if (ret) 781 goto err; 782 783 return 0; 784 785err: 786 kfree(dev); 787 printk(KERN_ERR "USB accessory gadget driver failed to initialize\n"); 788 return ret; 789} 790 791static void acc_cleanup(void) 792{ 793 misc_deregister(&acc_device); 794 kfree(_acc_dev); 795 _acc_dev = NULL; 796} 797