1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * f_phonet.c -- USB CDC Phonet function 4 * 5 * Copyright (C) 2007-2008 Nokia Corporation. All rights reserved. 6 * 7 * Author: Rémi Denis-Courmont 8 */ 9 10 #include <linux/mm.h> 11 #include <linux/slab.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/device.h> 15 16 #include <linux/netdevice.h> 17 #include <linux/if_ether.h> 18 #include <linux/if_phonet.h> 19 #include <linux/if_arp.h> 20 21 #include <linux/usb/ch9.h> 22 #include <linux/usb/cdc.h> 23 #include <linux/usb/composite.h> 24 25 #include "u_phonet.h" 26 #include "u_ether.h" 27 28 #define PN_MEDIA_USB 0x1B 29 #define MAXPACKET 512 30 #if (PAGE_SIZE % MAXPACKET) 31 #error MAXPACKET must divide PAGE_SIZE! 32 #endif 33 34 /*-------------------------------------------------------------------------*/ 35 36 struct phonet_port { 37 struct f_phonet *usb; 38 spinlock_t lock; 39 }; 40 41 struct f_phonet { 42 struct usb_function function; 43 struct { 44 struct sk_buff *skb; 45 spinlock_t lock; 46 } rx; 47 struct net_device *dev; 48 struct usb_ep *in_ep, *out_ep; 49 50 struct usb_request *in_req; 51 struct usb_request *out_reqv[]; 52 }; 53 54 static int phonet_rxq_size = 17; 55 56 static inline struct f_phonet *func_to_pn(struct usb_function *f) 57 { 58 return container_of(f, struct f_phonet, function); 59 } 60 61 /*-------------------------------------------------------------------------*/ 62 63 #define USB_CDC_SUBCLASS_PHONET 0xfe 64 #define USB_CDC_PHONET_TYPE 0xab 65 66 static struct usb_interface_descriptor 67 pn_control_intf_desc = { 68 .bLength = sizeof pn_control_intf_desc, 69 .bDescriptorType = USB_DT_INTERFACE, 70 71 /* .bInterfaceNumber = DYNAMIC, */ 72 .bInterfaceClass = USB_CLASS_COMM, 73 .bInterfaceSubClass = USB_CDC_SUBCLASS_PHONET, 74 }; 75 76 static const struct usb_cdc_header_desc 77 pn_header_desc = { 78 .bLength = sizeof pn_header_desc, 79 .bDescriptorType = USB_DT_CS_INTERFACE, 80 .bDescriptorSubType = USB_CDC_HEADER_TYPE, 81 .bcdCDC = cpu_to_le16(0x0110), 82 }; 83 84 static const struct usb_cdc_header_desc 85 pn_phonet_desc = { 86 .bLength = sizeof pn_phonet_desc, 87 .bDescriptorType = USB_DT_CS_INTERFACE, 88 .bDescriptorSubType = USB_CDC_PHONET_TYPE, 89 .bcdCDC = cpu_to_le16(0x1505), /* ??? */ 90 }; 91 92 static struct usb_cdc_union_desc 93 pn_union_desc = { 94 .bLength = sizeof pn_union_desc, 95 .bDescriptorType = USB_DT_CS_INTERFACE, 96 .bDescriptorSubType = USB_CDC_UNION_TYPE, 97 98 /* .bMasterInterface0 = DYNAMIC, */ 99 /* .bSlaveInterface0 = DYNAMIC, */ 100 }; 101 102 static struct usb_interface_descriptor 103 pn_data_nop_intf_desc = { 104 .bLength = sizeof pn_data_nop_intf_desc, 105 .bDescriptorType = USB_DT_INTERFACE, 106 107 /* .bInterfaceNumber = DYNAMIC, */ 108 .bAlternateSetting = 0, 109 .bNumEndpoints = 0, 110 .bInterfaceClass = USB_CLASS_CDC_DATA, 111 }; 112 113 static struct usb_interface_descriptor 114 pn_data_intf_desc = { 115 .bLength = sizeof pn_data_intf_desc, 116 .bDescriptorType = USB_DT_INTERFACE, 117 118 /* .bInterfaceNumber = DYNAMIC, */ 119 .bAlternateSetting = 1, 120 .bNumEndpoints = 2, 121 .bInterfaceClass = USB_CLASS_CDC_DATA, 122 }; 123 124 static struct usb_endpoint_descriptor 125 pn_fs_sink_desc = { 126 .bLength = USB_DT_ENDPOINT_SIZE, 127 .bDescriptorType = USB_DT_ENDPOINT, 128 129 .bEndpointAddress = USB_DIR_OUT, 130 .bmAttributes = USB_ENDPOINT_XFER_BULK, 131 }; 132 133 static struct usb_endpoint_descriptor 134 pn_hs_sink_desc = { 135 .bLength = USB_DT_ENDPOINT_SIZE, 136 .bDescriptorType = USB_DT_ENDPOINT, 137 138 .bEndpointAddress = USB_DIR_OUT, 139 .bmAttributes = USB_ENDPOINT_XFER_BULK, 140 .wMaxPacketSize = cpu_to_le16(MAXPACKET), 141 }; 142 143 static struct usb_endpoint_descriptor 144 pn_fs_source_desc = { 145 .bLength = USB_DT_ENDPOINT_SIZE, 146 .bDescriptorType = USB_DT_ENDPOINT, 147 148 .bEndpointAddress = USB_DIR_IN, 149 .bmAttributes = USB_ENDPOINT_XFER_BULK, 150 }; 151 152 static struct usb_endpoint_descriptor 153 pn_hs_source_desc = { 154 .bLength = USB_DT_ENDPOINT_SIZE, 155 .bDescriptorType = USB_DT_ENDPOINT, 156 157 .bEndpointAddress = USB_DIR_IN, 158 .bmAttributes = USB_ENDPOINT_XFER_BULK, 159 .wMaxPacketSize = cpu_to_le16(512), 160 }; 161 162 static struct usb_descriptor_header *fs_pn_function[] = { 163 (struct usb_descriptor_header *) &pn_control_intf_desc, 164 (struct usb_descriptor_header *) &pn_header_desc, 165 (struct usb_descriptor_header *) &pn_phonet_desc, 166 (struct usb_descriptor_header *) &pn_union_desc, 167 (struct usb_descriptor_header *) &pn_data_nop_intf_desc, 168 (struct usb_descriptor_header *) &pn_data_intf_desc, 169 (struct usb_descriptor_header *) &pn_fs_sink_desc, 170 (struct usb_descriptor_header *) &pn_fs_source_desc, 171 NULL, 172 }; 173 174 static struct usb_descriptor_header *hs_pn_function[] = { 175 (struct usb_descriptor_header *) &pn_control_intf_desc, 176 (struct usb_descriptor_header *) &pn_header_desc, 177 (struct usb_descriptor_header *) &pn_phonet_desc, 178 (struct usb_descriptor_header *) &pn_union_desc, 179 (struct usb_descriptor_header *) &pn_data_nop_intf_desc, 180 (struct usb_descriptor_header *) &pn_data_intf_desc, 181 (struct usb_descriptor_header *) &pn_hs_sink_desc, 182 (struct usb_descriptor_header *) &pn_hs_source_desc, 183 NULL, 184 }; 185 186 /*-------------------------------------------------------------------------*/ 187 188 static int pn_net_open(struct net_device *dev) 189 { 190 netif_wake_queue(dev); 191 return 0; 192 } 193 194 static int pn_net_close(struct net_device *dev) 195 { 196 netif_stop_queue(dev); 197 return 0; 198 } 199 200 static void pn_tx_complete(struct usb_ep *ep, struct usb_request *req) 201 { 202 struct f_phonet *fp = ep->driver_data; 203 struct net_device *dev = fp->dev; 204 struct sk_buff *skb = req->context; 205 206 switch (req->status) { 207 case 0: 208 dev->stats.tx_packets++; 209 dev->stats.tx_bytes += skb->len; 210 break; 211 212 case -ESHUTDOWN: /* disconnected */ 213 case -ECONNRESET: /* disabled */ 214 dev->stats.tx_aborted_errors++; 215 fallthrough; 216 default: 217 dev->stats.tx_errors++; 218 } 219 220 dev_kfree_skb_any(skb); 221 netif_wake_queue(dev); 222 } 223 224 static netdev_tx_t pn_net_xmit(struct sk_buff *skb, struct net_device *dev) 225 { 226 struct phonet_port *port = netdev_priv(dev); 227 struct f_phonet *fp; 228 struct usb_request *req; 229 unsigned long flags; 230 231 if (skb->protocol != htons(ETH_P_PHONET)) 232 goto out; 233 234 spin_lock_irqsave(&port->lock, flags); 235 fp = port->usb; 236 if (unlikely(!fp)) /* race with carrier loss */ 237 goto out_unlock; 238 239 req = fp->in_req; 240 req->buf = skb->data; 241 req->length = skb->len; 242 req->complete = pn_tx_complete; 243 req->zero = 1; 244 req->context = skb; 245 246 if (unlikely(usb_ep_queue(fp->in_ep, req, GFP_ATOMIC))) 247 goto out_unlock; 248 249 netif_stop_queue(dev); 250 skb = NULL; 251 252 out_unlock: 253 spin_unlock_irqrestore(&port->lock, flags); 254 out: 255 if (unlikely(skb)) { 256 dev_kfree_skb(skb); 257 dev->stats.tx_dropped++; 258 } 259 return NETDEV_TX_OK; 260 } 261 262 static const struct net_device_ops pn_netdev_ops = { 263 .ndo_open = pn_net_open, 264 .ndo_stop = pn_net_close, 265 .ndo_start_xmit = pn_net_xmit, 266 }; 267 268 static void pn_net_setup(struct net_device *dev) 269 { 270 const u8 addr = PN_MEDIA_USB; 271 272 dev->features = 0; 273 dev->type = ARPHRD_PHONET; 274 dev->flags = IFF_POINTOPOINT | IFF_NOARP; 275 dev->mtu = PHONET_DEV_MTU; 276 dev->min_mtu = PHONET_MIN_MTU; 277 dev->max_mtu = PHONET_MAX_MTU; 278 dev->hard_header_len = 1; 279 dev->addr_len = 1; 280 dev_addr_set(dev, &addr); 281 282 dev->tx_queue_len = 1; 283 284 dev->netdev_ops = &pn_netdev_ops; 285 dev->needs_free_netdev = true; 286 dev->header_ops = &phonet_header_ops; 287 } 288 289 /*-------------------------------------------------------------------------*/ 290 291 /* 292 * Queue buffer for data from the host 293 */ 294 static int 295 pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags) 296 { 297 struct page *page; 298 int err; 299 300 page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC); 301 if (!page) 302 return -ENOMEM; 303 304 req->buf = page_address(page); 305 req->length = PAGE_SIZE; 306 req->context = page; 307 308 err = usb_ep_queue(fp->out_ep, req, gfp_flags); 309 if (unlikely(err)) 310 put_page(page); 311 return err; 312 } 313 314 static void pn_rx_complete(struct usb_ep *ep, struct usb_request *req) 315 { 316 struct f_phonet *fp = ep->driver_data; 317 struct net_device *dev = fp->dev; 318 struct page *page = req->context; 319 struct sk_buff *skb; 320 unsigned long flags; 321 int status = req->status; 322 323 switch (status) { 324 case 0: 325 spin_lock_irqsave(&fp->rx.lock, flags); 326 skb = fp->rx.skb; 327 if (!skb) 328 skb = fp->rx.skb = netdev_alloc_skb(dev, 12); 329 if (req->actual < req->length) /* Last fragment */ 330 fp->rx.skb = NULL; 331 spin_unlock_irqrestore(&fp->rx.lock, flags); 332 333 if (unlikely(!skb)) 334 break; 335 336 if (skb->len == 0) { /* First fragment */ 337 skb->protocol = htons(ETH_P_PHONET); 338 skb_reset_mac_header(skb); 339 /* Can't use pskb_pull() on page in IRQ */ 340 skb_put_data(skb, page_address(page), 1); 341 } 342 343 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, 344 skb->len <= 1, req->actual, PAGE_SIZE); 345 page = NULL; 346 347 if (req->actual < req->length) { /* Last fragment */ 348 skb->dev = dev; 349 dev->stats.rx_packets++; 350 dev->stats.rx_bytes += skb->len; 351 352 netif_rx(skb); 353 } 354 break; 355 356 /* Do not resubmit in these cases: */ 357 case -ESHUTDOWN: /* disconnect */ 358 case -ECONNABORTED: /* hw reset */ 359 case -ECONNRESET: /* dequeued (unlink or netif down) */ 360 req = NULL; 361 break; 362 363 /* Do resubmit in these cases: */ 364 case -EOVERFLOW: /* request buffer overflow */ 365 dev->stats.rx_over_errors++; 366 fallthrough; 367 default: 368 dev->stats.rx_errors++; 369 break; 370 } 371 372 if (page) 373 put_page(page); 374 if (req) 375 pn_rx_submit(fp, req, GFP_ATOMIC); 376 } 377 378 /*-------------------------------------------------------------------------*/ 379 380 static void __pn_reset(struct usb_function *f) 381 { 382 struct f_phonet *fp = func_to_pn(f); 383 struct net_device *dev = fp->dev; 384 struct phonet_port *port = netdev_priv(dev); 385 386 netif_carrier_off(dev); 387 port->usb = NULL; 388 389 usb_ep_disable(fp->out_ep); 390 usb_ep_disable(fp->in_ep); 391 if (fp->rx.skb) { 392 dev_kfree_skb_irq(fp->rx.skb); 393 fp->rx.skb = NULL; 394 } 395 } 396 397 static int pn_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 398 { 399 struct f_phonet *fp = func_to_pn(f); 400 struct usb_gadget *gadget = fp->function.config->cdev->gadget; 401 402 if (intf == pn_control_intf_desc.bInterfaceNumber) 403 /* control interface, no altsetting */ 404 return (alt > 0) ? -EINVAL : 0; 405 406 if (intf == pn_data_intf_desc.bInterfaceNumber) { 407 struct net_device *dev = fp->dev; 408 struct phonet_port *port = netdev_priv(dev); 409 410 /* data intf (0: inactive, 1: active) */ 411 if (alt > 1) 412 return -EINVAL; 413 414 spin_lock(&port->lock); 415 416 if (fp->in_ep->enabled) 417 __pn_reset(f); 418 419 if (alt == 1) { 420 int i; 421 422 if (config_ep_by_speed(gadget, f, fp->in_ep) || 423 config_ep_by_speed(gadget, f, fp->out_ep)) { 424 fp->in_ep->desc = NULL; 425 fp->out_ep->desc = NULL; 426 spin_unlock(&port->lock); 427 return -EINVAL; 428 } 429 usb_ep_enable(fp->out_ep); 430 usb_ep_enable(fp->in_ep); 431 432 port->usb = fp; 433 fp->out_ep->driver_data = fp; 434 fp->in_ep->driver_data = fp; 435 436 netif_carrier_on(dev); 437 for (i = 0; i < phonet_rxq_size; i++) 438 pn_rx_submit(fp, fp->out_reqv[i], GFP_ATOMIC); 439 } 440 spin_unlock(&port->lock); 441 return 0; 442 } 443 444 return -EINVAL; 445 } 446 447 static int pn_get_alt(struct usb_function *f, unsigned intf) 448 { 449 struct f_phonet *fp = func_to_pn(f); 450 451 if (intf == pn_control_intf_desc.bInterfaceNumber) 452 return 0; 453 454 if (intf == pn_data_intf_desc.bInterfaceNumber) { 455 struct phonet_port *port = netdev_priv(fp->dev); 456 u8 alt; 457 458 spin_lock(&port->lock); 459 alt = port->usb != NULL; 460 spin_unlock(&port->lock); 461 return alt; 462 } 463 464 return -EINVAL; 465 } 466 467 static void pn_disconnect(struct usb_function *f) 468 { 469 struct f_phonet *fp = func_to_pn(f); 470 struct phonet_port *port = netdev_priv(fp->dev); 471 unsigned long flags; 472 473 /* remain disabled until set_alt */ 474 spin_lock_irqsave(&port->lock, flags); 475 __pn_reset(f); 476 spin_unlock_irqrestore(&port->lock, flags); 477 } 478 479 /*-------------------------------------------------------------------------*/ 480 481 static int pn_bind(struct usb_configuration *c, struct usb_function *f) 482 { 483 struct usb_composite_dev *cdev = c->cdev; 484 struct usb_gadget *gadget = cdev->gadget; 485 struct f_phonet *fp = func_to_pn(f); 486 struct usb_ep *ep; 487 int status, i; 488 489 struct f_phonet_opts *phonet_opts; 490 491 phonet_opts = container_of(f->fi, struct f_phonet_opts, func_inst); 492 493 /* 494 * in drivers/usb/gadget/configfs.c:configfs_composite_bind() 495 * configurations are bound in sequence with list_for_each_entry, 496 * in each configuration its functions are bound in sequence 497 * with list_for_each_entry, so we assume no race condition 498 * with regard to phonet_opts->bound access 499 */ 500 if (!phonet_opts->bound) { 501 gphonet_set_gadget(phonet_opts->net, gadget); 502 status = gphonet_register_netdev(phonet_opts->net); 503 if (status) 504 return status; 505 phonet_opts->bound = true; 506 } 507 508 /* Reserve interface IDs */ 509 status = usb_interface_id(c, f); 510 if (status < 0) 511 goto err; 512 pn_control_intf_desc.bInterfaceNumber = status; 513 pn_union_desc.bMasterInterface0 = status; 514 515 status = usb_interface_id(c, f); 516 if (status < 0) 517 goto err; 518 pn_data_nop_intf_desc.bInterfaceNumber = status; 519 pn_data_intf_desc.bInterfaceNumber = status; 520 pn_union_desc.bSlaveInterface0 = status; 521 522 /* Reserve endpoints */ 523 status = -ENODEV; 524 ep = usb_ep_autoconfig(gadget, &pn_fs_sink_desc); 525 if (!ep) 526 goto err; 527 fp->out_ep = ep; 528 529 ep = usb_ep_autoconfig(gadget, &pn_fs_source_desc); 530 if (!ep) 531 goto err; 532 fp->in_ep = ep; 533 534 pn_hs_sink_desc.bEndpointAddress = pn_fs_sink_desc.bEndpointAddress; 535 pn_hs_source_desc.bEndpointAddress = pn_fs_source_desc.bEndpointAddress; 536 537 /* Do not try to bind Phonet twice... */ 538 status = usb_assign_descriptors(f, fs_pn_function, hs_pn_function, 539 NULL, NULL); 540 if (status) 541 goto err; 542 543 /* Incoming USB requests */ 544 status = -ENOMEM; 545 for (i = 0; i < phonet_rxq_size; i++) { 546 struct usb_request *req; 547 548 req = usb_ep_alloc_request(fp->out_ep, GFP_KERNEL); 549 if (!req) 550 goto err_req; 551 552 req->complete = pn_rx_complete; 553 fp->out_reqv[i] = req; 554 } 555 556 /* Outgoing USB requests */ 557 fp->in_req = usb_ep_alloc_request(fp->in_ep, GFP_KERNEL); 558 if (!fp->in_req) 559 goto err_req; 560 561 INFO(cdev, "USB CDC Phonet function\n"); 562 INFO(cdev, "using %s, OUT %s, IN %s\n", cdev->gadget->name, 563 fp->out_ep->name, fp->in_ep->name); 564 return 0; 565 566 err_req: 567 for (i = 0; i < phonet_rxq_size && fp->out_reqv[i]; i++) 568 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]); 569 usb_free_all_descriptors(f); 570 err: 571 ERROR(cdev, "USB CDC Phonet: cannot autoconfigure\n"); 572 return status; 573 } 574 575 static inline struct f_phonet_opts *to_f_phonet_opts(struct config_item *item) 576 { 577 return container_of(to_config_group(item), struct f_phonet_opts, 578 func_inst.group); 579 } 580 581 static void phonet_attr_release(struct config_item *item) 582 { 583 struct f_phonet_opts *opts = to_f_phonet_opts(item); 584 585 usb_put_function_instance(&opts->func_inst); 586 } 587 588 static struct configfs_item_operations phonet_item_ops = { 589 .release = phonet_attr_release, 590 }; 591 592 static ssize_t f_phonet_ifname_show(struct config_item *item, char *page) 593 { 594 return gether_get_ifname(to_f_phonet_opts(item)->net, page, PAGE_SIZE); 595 } 596 597 CONFIGFS_ATTR_RO(f_phonet_, ifname); 598 599 static struct configfs_attribute *phonet_attrs[] = { 600 &f_phonet_attr_ifname, 601 NULL, 602 }; 603 604 static const struct config_item_type phonet_func_type = { 605 .ct_item_ops = &phonet_item_ops, 606 .ct_attrs = phonet_attrs, 607 .ct_owner = THIS_MODULE, 608 }; 609 610 static void phonet_free_inst(struct usb_function_instance *f) 611 { 612 struct f_phonet_opts *opts; 613 614 opts = container_of(f, struct f_phonet_opts, func_inst); 615 if (opts->bound) 616 gphonet_cleanup(opts->net); 617 else 618 free_netdev(opts->net); 619 kfree(opts); 620 } 621 622 static struct usb_function_instance *phonet_alloc_inst(void) 623 { 624 struct f_phonet_opts *opts; 625 626 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 627 if (!opts) 628 return ERR_PTR(-ENOMEM); 629 630 opts->func_inst.free_func_inst = phonet_free_inst; 631 opts->net = gphonet_setup_default(); 632 if (IS_ERR(opts->net)) { 633 struct net_device *net = opts->net; 634 kfree(opts); 635 return ERR_CAST(net); 636 } 637 638 config_group_init_type_name(&opts->func_inst.group, "", 639 &phonet_func_type); 640 641 return &opts->func_inst; 642 } 643 644 static void phonet_free(struct usb_function *f) 645 { 646 struct f_phonet *phonet; 647 648 phonet = func_to_pn(f); 649 kfree(phonet); 650 } 651 652 static void pn_unbind(struct usb_configuration *c, struct usb_function *f) 653 { 654 struct f_phonet *fp = func_to_pn(f); 655 int i; 656 657 /* We are already disconnected */ 658 if (fp->in_req) 659 usb_ep_free_request(fp->in_ep, fp->in_req); 660 for (i = 0; i < phonet_rxq_size; i++) 661 if (fp->out_reqv[i]) 662 usb_ep_free_request(fp->out_ep, fp->out_reqv[i]); 663 664 usb_free_all_descriptors(f); 665 } 666 667 static struct usb_function *phonet_alloc(struct usb_function_instance *fi) 668 { 669 struct f_phonet *fp; 670 struct f_phonet_opts *opts; 671 672 fp = kzalloc(struct_size(fp, out_reqv, phonet_rxq_size), GFP_KERNEL); 673 if (!fp) 674 return ERR_PTR(-ENOMEM); 675 676 opts = container_of(fi, struct f_phonet_opts, func_inst); 677 678 fp->dev = opts->net; 679 fp->function.name = "phonet"; 680 fp->function.bind = pn_bind; 681 fp->function.unbind = pn_unbind; 682 fp->function.set_alt = pn_set_alt; 683 fp->function.get_alt = pn_get_alt; 684 fp->function.disable = pn_disconnect; 685 fp->function.free_func = phonet_free; 686 spin_lock_init(&fp->rx.lock); 687 688 return &fp->function; 689 } 690 691 struct net_device *gphonet_setup_default(void) 692 { 693 struct net_device *dev; 694 struct phonet_port *port; 695 696 /* Create net device */ 697 dev = alloc_netdev(sizeof(*port), "upnlink%d", NET_NAME_UNKNOWN, 698 pn_net_setup); 699 if (!dev) 700 return ERR_PTR(-ENOMEM); 701 702 port = netdev_priv(dev); 703 spin_lock_init(&port->lock); 704 netif_carrier_off(dev); 705 706 return dev; 707 } 708 709 void gphonet_set_gadget(struct net_device *net, struct usb_gadget *g) 710 { 711 SET_NETDEV_DEV(net, &g->dev); 712 } 713 714 int gphonet_register_netdev(struct net_device *net) 715 { 716 int status; 717 718 status = register_netdev(net); 719 if (status) 720 free_netdev(net); 721 722 return status; 723 } 724 725 void gphonet_cleanup(struct net_device *dev) 726 { 727 unregister_netdev(dev); 728 } 729 730 DECLARE_USB_FUNCTION_INIT(phonet, phonet_alloc_inst, phonet_alloc); 731 MODULE_AUTHOR("Rémi Denis-Courmont"); 732 MODULE_DESCRIPTION("USB CDC Phonet function"); 733 MODULE_LICENSE("GPL"); 734