drivers/net/usb/ipheth.c

   1 /*
   2  * ipheth.c - Apple iPhone USB Ethernet driver
   3  *
   4  * Copyright (c) 2009 Diego Giagio <diego@giagio.com>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of GIAGIO.COM nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * Alternatively, provided that this notice is retained in full, this
  20  * software may be distributed under the terms of the GNU General
  21  * Public License ("GPL") version 2, in which case the provisions of the
  22  * GPL apply INSTEAD OF those given above.
  23  *
  24  * The provided data structures and external interfaces from this code
  25  * are not restricted to be used by modules with a GPL compatible license.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  30  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  31  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  32  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  33  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  35  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  36  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  37  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  38  * DAMAGE.
  39  *
  40  *
  41  * Attention: iPhone device must be paired, otherwise it won't respond to our
  42  * driver. For more info: http://giagio.com/wiki/moin.cgi/iPhoneEthernetDriver
  43  *
  44  */
  45
  46 #include <linux/kernel.h>
  47 #include <linux/errno.h>
  48 #include <linux/slab.h>
  49 #include <linux/module.h>
  50 #include <linux/netdevice.h>
  51 #include <linux/etherdevice.h>
  52 #include <linux/ethtool.h>
  53 #include <linux/usb.h>
  54 #include <linux/workqueue.h>
  55 #include <linux/usb/cdc.h>
  56
  57 #define USB_VENDOR_APPLE        0x05ac
  58
  59 #define IPHETH_USBINTF_CLASS    255
  60 #define IPHETH_USBINTF_SUBCLASS 253
  61 #define IPHETH_USBINTF_PROTO    1
  62
  63 #define IPHETH_IP_ALIGN         2       /* padding at front of URB */
  64 #define IPHETH_NCM_HEADER_SIZE  (12 + 96) /* NCMH + NCM0 */
  65 #define IPHETH_TX_BUF_SIZE      ETH_FRAME_LEN
  66 #define IPHETH_RX_BUF_SIZE_LEGACY (IPHETH_IP_ALIGN + ETH_FRAME_LEN)
  67 #define IPHETH_RX_BUF_SIZE_NCM  65536
  68
  69 #define IPHETH_TX_TIMEOUT       (5 * HZ)
  70
  71 #define IPHETH_INTFNUM          2
  72 #define IPHETH_ALT_INTFNUM      1
  73
  74 #define IPHETH_CTRL_ENDP        0x00
  75 #define IPHETH_CTRL_BUF_SIZE    0x40
  76 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
  77
  78 #define IPHETH_CMD_GET_MACADDR   0x00
  79 #define IPHETH_CMD_ENABLE_NCM    0x04
  80 #define IPHETH_CMD_CARRIER_CHECK 0x45
  81
  82 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
  83 #define IPHETH_CARRIER_ON       0x04
  84
  85 static const struct usb_device_id ipheth_table[] = {
  86         { USB_VENDOR_AND_INTERFACE_INFO(USB_VENDOR_APPLE, IPHETH_USBINTF_CLASS,
  87                                         IPHETH_USBINTF_SUBCLASS,
  88                                         IPHETH_USBINTF_PROTO) },
  89         { }
  90 };
  91 MODULE_DEVICE_TABLE(usb, ipheth_table);
  92
  93 struct ipheth_device {
  94         struct usb_device *udev;
  95         struct usb_interface *intf;
  96         struct net_device *net;
  97         struct urb *tx_urb;
  98         struct urb *rx_urb;
  99         unsigned char *tx_buf;
 100         unsigned char *rx_buf;
 101         unsigned char *ctrl_buf;
 102         u8 bulk_in;
 103         u8 bulk_out;
 104         struct delayed_work carrier_work;
 105         bool confirmed_pairing;
 106         int (*rcvbulk_callback)(struct urb *urb);
 107         size_t rx_buf_len;
 108 };
 109
 110 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
 111
 112 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
 113 {
 114         struct urb *tx_urb = NULL;
 115         struct urb *rx_urb = NULL;
 116         u8 *tx_buf = NULL;
 117         u8 *rx_buf = NULL;
 118
 119         tx_urb = usb_alloc_urb(0, GFP_KERNEL);
 120         if (tx_urb == NULL)
 121                 goto error_nomem;
 122
 123         rx_urb = usb_alloc_urb(0, GFP_KERNEL);
 124         if (rx_urb == NULL)
 125                 goto free_tx_urb;
 126
 127         tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_TX_BUF_SIZE,
 128                                     GFP_KERNEL, &tx_urb->transfer_dma);
 129         if (tx_buf == NULL)
 130                 goto free_rx_urb;
 131
 132         rx_buf = usb_alloc_coherent(iphone->udev, iphone->rx_buf_len,
 133                                     GFP_KERNEL, &rx_urb->transfer_dma);
 134         if (rx_buf == NULL)
 135                 goto free_tx_buf;
 136
 137
 138         iphone->tx_urb = tx_urb;
 139         iphone->rx_urb = rx_urb;
 140         iphone->tx_buf = tx_buf;
 141         iphone->rx_buf = rx_buf;
 142         return 0;
 143
 144 free_tx_buf:
 145         usb_free_coherent(iphone->udev, IPHETH_TX_BUF_SIZE, tx_buf,
 146                           tx_urb->transfer_dma);
 147 free_rx_urb:
 148         usb_free_urb(rx_urb);
 149 free_tx_urb:
 150         usb_free_urb(tx_urb);
 151 error_nomem:
 152         return -ENOMEM;
 153 }
 154
 155 static void ipheth_free_urbs(struct ipheth_device *iphone)
 156 {
 157         usb_free_coherent(iphone->udev, iphone->rx_buf_len, iphone->rx_buf,
 158                           iphone->rx_urb->transfer_dma);
 159         usb_free_coherent(iphone->udev, IPHETH_TX_BUF_SIZE, iphone->tx_buf,
 160                           iphone->tx_urb->transfer_dma);
 161         usb_free_urb(iphone->rx_urb);
 162         usb_free_urb(iphone->tx_urb);
 163 }
 164
 165 static void ipheth_kill_urbs(struct ipheth_device *dev)
 166 {
 167         usb_kill_urb(dev->tx_urb);
 168         usb_kill_urb(dev->rx_urb);
 169 }
 170
 171 static int ipheth_consume_skb(char *buf, int len, struct ipheth_device *dev)
 172 {
 173         struct sk_buff *skb;
 174
 175         skb = dev_alloc_skb(len);
 176         if (!skb) {
 177                 dev->net->stats.rx_dropped++;
 178                 return -ENOMEM;
 179         }
 180
 181         skb_put_data(skb, buf, len);
 182         skb->dev = dev->net;
 183         skb->protocol = eth_type_trans(skb, dev->net);
 184
 185         dev->net->stats.rx_packets++;
 186         dev->net->stats.rx_bytes += len;
 187         netif_rx(skb);
 188
 189         return 0;
 190 }
 191
 192 static int ipheth_rcvbulk_callback_legacy(struct urb *urb)
 193 {
 194         struct ipheth_device *dev;
 195         char *buf;
 196         int len;
 197
 198         dev = urb->context;
 199
 200         if (urb->actual_length <= IPHETH_IP_ALIGN) {
 201                 dev->net->stats.rx_length_errors++;
 202                 return -EINVAL;
 203         }
 204         len = urb->actual_length - IPHETH_IP_ALIGN;
 205         buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
 206
 207         return ipheth_consume_skb(buf, len, dev);
 208 }
 209
 210 static int ipheth_rcvbulk_callback_ncm(struct urb *urb)
 211 {
 212         struct usb_cdc_ncm_nth16 *ncmh;
 213         struct usb_cdc_ncm_ndp16 *ncm0;
 214         struct usb_cdc_ncm_dpe16 *dpe;
 215         struct ipheth_device *dev;
 216         int retval = -EINVAL;
 217         char *buf;
 218         int len;
 219
 220         dev = urb->context;
 221
 222         if (urb->actual_length < IPHETH_NCM_HEADER_SIZE) {
 223                 dev->net->stats.rx_length_errors++;
 224                 return retval;
 225         }
 226
 227         ncmh = urb->transfer_buffer;
 228         if (ncmh->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN) ||
 229             le16_to_cpu(ncmh->wNdpIndex) >= urb->actual_length) {
 230                 dev->net->stats.rx_errors++;
 231                 return retval;
 232         }
 233
 234         ncm0 = urb->transfer_buffer + le16_to_cpu(ncmh->wNdpIndex);
 235         if (ncm0->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN) ||
 236             le16_to_cpu(ncmh->wHeaderLength) + le16_to_cpu(ncm0->wLength) >=
 237             urb->actual_length) {
 238                 dev->net->stats.rx_errors++;
 239                 return retval;
 240         }
 241
 242         dpe = ncm0->dpe16;
 243         while (le16_to_cpu(dpe->wDatagramIndex) != 0 &&
 244                le16_to_cpu(dpe->wDatagramLength) != 0) {
 245                 if (le16_to_cpu(dpe->wDatagramIndex) >= urb->actual_length ||
 246                     le16_to_cpu(dpe->wDatagramIndex) +
 247                     le16_to_cpu(dpe->wDatagramLength) > urb->actual_length) {
 248                         dev->net->stats.rx_length_errors++;
 249                         return retval;
 250                 }
 251
 252                 buf = urb->transfer_buffer + le16_to_cpu(dpe->wDatagramIndex);
 253                 len = le16_to_cpu(dpe->wDatagramLength);
 254
 255                 retval = ipheth_consume_skb(buf, len, dev);
 256                 if (retval != 0)
 257                         return retval;
 258
 259                 dpe++;
 260         }
 261
 262         return 0;
 263 }
 264
 265 static void ipheth_rcvbulk_callback(struct urb *urb)
 266 {
 267         struct ipheth_device *dev;
 268         int retval, status;
 269
 270         dev = urb->context;
 271         if (dev == NULL)
 272                 return;
 273
 274         status = urb->status;
 275         switch (status) {
 276         case -ENOENT:
 277         case -ECONNRESET:
 278         case -ESHUTDOWN:
 279         case -EPROTO:
 280                 return;
 281         case 0:
 282                 break;
 283         default:
 284                 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
 285                         __func__, status);
 286                 return;
 287         }
 288
 289         if (urb->actual_length <= IPHETH_IP_ALIGN) {
 290                 dev->net->stats.rx_length_errors++;
 291                 return;
 292         }
 293
 294         /* RX URBs starting with 0x00 0x01 do not encapsulate Ethernet frames,
 295          * but rather are control frames. Their purpose is not documented, and
 296          * they don't affect driver functionality, okay to drop them.
 297          * There is usually just one 4-byte control frame as the very first
 298          * URB received from the bulk IN endpoint.
 299          */
 300         if (unlikely
 301                 (((char *)urb->transfer_buffer)[0] == 0 &&
 302                  ((char *)urb->transfer_buffer)[1] == 1))
 303                 goto rx_submit;
 304
 305         retval = dev->rcvbulk_callback(urb);
 306         if (retval != 0) {
 307                 dev_err(&dev->intf->dev, "%s: callback retval: %d\n",
 308                         __func__, retval);
 309                 return;
 310         }
 311
 312 rx_submit:
 313         dev->confirmed_pairing = true;
 314         ipheth_rx_submit(dev, GFP_ATOMIC);
 315 }
 316
 317 static void ipheth_sndbulk_callback(struct urb *urb)
 318 {
 319         struct ipheth_device *dev;
 320         int status = urb->status;
 321
 322         dev = urb->context;
 323         if (dev == NULL)
 324                 return;
 325
 326         if (status != 0 &&
 327             status != -ENOENT &&
 328             status != -ECONNRESET &&
 329             status != -ESHUTDOWN)
 330                 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
 331                 __func__, status);
 332
 333         if (status == 0)
 334                 netif_wake_queue(dev->net);
 335         else
 336                 // on URB error, trigger immediate poll
 337                 schedule_delayed_work(&dev->carrier_work, 0);
 338 }
 339
 340 static int ipheth_carrier_set(struct ipheth_device *dev)
 341 {
 342         struct usb_device *udev;
 343         int retval;
 344
 345         if (!dev->confirmed_pairing)
 346                 return 0;
 347
 348         udev = dev->udev;
 349         retval = usb_control_msg(udev,
 350                         usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
 351                         IPHETH_CMD_CARRIER_CHECK, /* request */
 352                         0xc0, /* request type */
 353                         0x00, /* value */
 354                         0x02, /* index */
 355                         dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
 356                         IPHETH_CTRL_TIMEOUT);
 357         if (retval < 0) {
 358                 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
 359                         __func__, retval);
 360                 return retval;
 361         }
 362
 363         if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON) {
 364                 netif_carrier_on(dev->net);
 365                 if (dev->tx_urb->status != -EINPROGRESS)
 366                         netif_wake_queue(dev->net);
 367         } else {
 368                 netif_carrier_off(dev->net);
 369                 netif_stop_queue(dev->net);
 370         }
 371         return 0;
 372 }
 373
 374 static void ipheth_carrier_check_work(struct work_struct *work)
 375 {
 376         struct ipheth_device *dev = container_of(work, struct ipheth_device,
 377                                                  carrier_work.work);
 378
 379         ipheth_carrier_set(dev);
 380         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
 381 }
 382
 383 static int ipheth_get_macaddr(struct ipheth_device *dev)
 384 {
 385         struct usb_device *udev = dev->udev;
 386         struct net_device *net = dev->net;
 387         int retval;
 388
 389         retval = usb_control_msg(udev,
 390                                  usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
 391                                  IPHETH_CMD_GET_MACADDR, /* request */
 392                                  0xc0, /* request type */
 393                                  0x00, /* value */
 394                                  0x02, /* index */
 395                                  dev->ctrl_buf,
 396                                  IPHETH_CTRL_BUF_SIZE,
 397                                  IPHETH_CTRL_TIMEOUT);
 398         if (retval < 0) {
 399                 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
 400                         __func__, retval);
 401         } else if (retval < ETH_ALEN) {
 402                 dev_err(&dev->intf->dev,
 403                         "%s: usb_control_msg: short packet: %d bytes\n",
 404                         __func__, retval);
 405                 retval = -EINVAL;
 406         } else {
 407                 eth_hw_addr_set(net, dev->ctrl_buf);
 408                 retval = 0;
 409         }
 410
 411         return retval;
 412 }
 413
 414 static int ipheth_enable_ncm(struct ipheth_device *dev)
 415 {
 416         struct usb_device *udev = dev->udev;
 417         int retval;
 418
 419         retval = usb_control_msg(udev,
 420                                  usb_sndctrlpipe(udev, IPHETH_CTRL_ENDP),
 421                                  IPHETH_CMD_ENABLE_NCM, /* request */
 422                                  0x41, /* request type */
 423                                  0x00, /* value */
 424                                  0x02, /* index */
 425                                  NULL,
 426                                  0,
 427                                  IPHETH_CTRL_TIMEOUT);
 428
 429         dev_info(&dev->intf->dev, "%s: usb_control_msg: %d\n",
 430                  __func__, retval);
 431
 432         return retval;
 433 }
 434
 435 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
 436 {
 437         struct usb_device *udev = dev->udev;
 438         int retval;
 439
 440         usb_fill_bulk_urb(dev->rx_urb, udev,
 441                           usb_rcvbulkpipe(udev, dev->bulk_in),
 442                           dev->rx_buf, dev->rx_buf_len,
 443                           ipheth_rcvbulk_callback,
 444                           dev);
 445         dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 446
 447         retval = usb_submit_urb(dev->rx_urb, mem_flags);
 448         if (retval)
 449                 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
 450                         __func__, retval);
 451         return retval;
 452 }
 453
 454 static int ipheth_open(struct net_device *net)
 455 {
 456         struct ipheth_device *dev = netdev_priv(net);
 457         struct usb_device *udev = dev->udev;
 458         int retval = 0;
 459
 460         usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
 461
 462         retval = ipheth_carrier_set(dev);
 463         if (retval)
 464                 return retval;
 465
 466         retval = ipheth_rx_submit(dev, GFP_KERNEL);
 467         if (retval)
 468                 return retval;
 469
 470         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
 471         return retval;
 472 }
 473
 474 static int ipheth_close(struct net_device *net)
 475 {
 476         struct ipheth_device *dev = netdev_priv(net);
 477
 478         cancel_delayed_work_sync(&dev->carrier_work);
 479         netif_stop_queue(net);
 480         return 0;
 481 }
 482
 483 static netdev_tx_t ipheth_tx(struct sk_buff *skb, struct net_device *net)
 484 {
 485         struct ipheth_device *dev = netdev_priv(net);
 486         struct usb_device *udev = dev->udev;
 487         int retval;
 488
 489         /* Paranoid */
 490         if (skb->len > IPHETH_TX_BUF_SIZE) {
 491                 WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
 492                 dev->net->stats.tx_dropped++;
 493                 dev_kfree_skb_any(skb);
 494                 return NETDEV_TX_OK;
 495         }
 496
 497         memcpy(dev->tx_buf, skb->data, skb->len);
 498
 499         usb_fill_bulk_urb(dev->tx_urb, udev,
 500                           usb_sndbulkpipe(udev, dev->bulk_out),
 501                           dev->tx_buf, skb->len,
 502                           ipheth_sndbulk_callback,
 503                           dev);
 504         dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 505
 506         netif_stop_queue(net);
 507         retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
 508         if (retval) {
 509                 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
 510                         __func__, retval);
 511                 dev->net->stats.tx_errors++;
 512                 dev_kfree_skb_any(skb);
 513                 netif_wake_queue(net);
 514         } else {
 515                 dev->net->stats.tx_packets++;
 516                 dev->net->stats.tx_bytes += skb->len;
 517                 dev_consume_skb_any(skb);
 518         }
 519
 520         return NETDEV_TX_OK;
 521 }
 522
 523 static void ipheth_tx_timeout(struct net_device *net, unsigned int txqueue)
 524 {
 525         struct ipheth_device *dev = netdev_priv(net);
 526
 527         dev_err(&dev->intf->dev, "%s: TX timeout\n", __func__);
 528         dev->net->stats.tx_errors++;
 529         usb_unlink_urb(dev->tx_urb);
 530 }
 531
 532 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
 533 {
 534         struct ipheth_device *dev = netdev_priv(net);
 535         return netif_carrier_ok(dev->net);
 536 }
 537
 538 static const struct ethtool_ops ops = {
 539         .get_link = ipheth_ethtool_op_get_link
 540 };
 541
 542 static const struct net_device_ops ipheth_netdev_ops = {
 543         .ndo_open = ipheth_open,
 544         .ndo_stop = ipheth_close,
 545         .ndo_start_xmit = ipheth_tx,
 546         .ndo_tx_timeout = ipheth_tx_timeout,
 547 };
 548
 549 static int ipheth_probe(struct usb_interface *intf,
 550                         const struct usb_device_id *id)
 551 {
 552         struct usb_device *udev = interface_to_usbdev(intf);
 553         struct usb_host_interface *hintf;
 554         struct usb_endpoint_descriptor *endp;
 555         struct ipheth_device *dev;
 556         struct net_device *netdev;
 557         int i;
 558         int retval;
 559
 560         netdev = alloc_etherdev(sizeof(struct ipheth_device));
 561         if (!netdev)
 562                 return -ENOMEM;
 563
 564         netdev->netdev_ops = &ipheth_netdev_ops;
 565         netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
 566         strscpy(netdev->name, "eth%d", sizeof(netdev->name));
 567
 568         dev = netdev_priv(netdev);
 569         dev->udev = udev;
 570         dev->net = netdev;
 571         dev->intf = intf;
 572         dev->confirmed_pairing = false;
 573         dev->rx_buf_len = IPHETH_RX_BUF_SIZE_LEGACY;
 574         dev->rcvbulk_callback = ipheth_rcvbulk_callback_legacy;
 575         /* Set up endpoints */
 576         hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
 577         if (hintf == NULL) {
 578                 retval = -ENODEV;
 579                 dev_err(&intf->dev, "Unable to find alternate settings interface\n");
 580                 goto err_endpoints;
 581         }
 582
 583         for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
 584                 endp = &hintf->endpoint[i].desc;
 585                 if (usb_endpoint_is_bulk_in(endp))
 586                         dev->bulk_in = endp->bEndpointAddress;
 587                 else if (usb_endpoint_is_bulk_out(endp))
 588                         dev->bulk_out = endp->bEndpointAddress;
 589         }
 590         if (!(dev->bulk_in && dev->bulk_out)) {
 591                 retval = -ENODEV;
 592                 dev_err(&intf->dev, "Unable to find endpoints\n");
 593                 goto err_endpoints;
 594         }
 595
 596         dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
 597         if (dev->ctrl_buf == NULL) {
 598                 retval = -ENOMEM;
 599                 goto err_alloc_ctrl_buf;
 600         }
 601
 602         retval = ipheth_get_macaddr(dev);
 603         if (retval)
 604                 goto err_get_macaddr;
 605
 606         retval = ipheth_enable_ncm(dev);
 607         if (!retval) {
 608                 dev->rx_buf_len = IPHETH_RX_BUF_SIZE_NCM;
 609                 dev->rcvbulk_callback = ipheth_rcvbulk_callback_ncm;
 610         }
 611
 612         INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
 613
 614         retval = ipheth_alloc_urbs(dev);
 615         if (retval) {
 616                 dev_err(&intf->dev, "error allocating urbs: %d\n", retval);
 617                 goto err_alloc_urbs;
 618         }
 619
 620         usb_set_intfdata(intf, dev);
 621
 622         SET_NETDEV_DEV(netdev, &intf->dev);
 623         netdev->ethtool_ops = &ops;
 624
 625         retval = register_netdev(netdev);
 626         if (retval) {
 627                 dev_err(&intf->dev, "error registering netdev: %d\n", retval);
 628                 retval = -EIO;
 629                 goto err_register_netdev;
 630         }
 631         // carrier down and transmit queues stopped until packet from device
 632         netif_carrier_off(netdev);
 633         netif_tx_stop_all_queues(netdev);
 634         dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
 635         return 0;
 636
 637 err_register_netdev:
 638         ipheth_free_urbs(dev);
 639 err_alloc_urbs:
 640 err_get_macaddr:
 641         kfree(dev->ctrl_buf);
 642 err_alloc_ctrl_buf:
 643 err_endpoints:
 644         free_netdev(netdev);
 645         return retval;
 646 }
 647
 648 static void ipheth_disconnect(struct usb_interface *intf)
 649 {
 650         struct ipheth_device *dev;
 651
 652         dev = usb_get_intfdata(intf);
 653         if (dev != NULL) {
 654                 unregister_netdev(dev->net);
 655                 ipheth_kill_urbs(dev);
 656                 ipheth_free_urbs(dev);
 657                 kfree(dev->ctrl_buf);
 658                 free_netdev(dev->net);
 659         }
 660         usb_set_intfdata(intf, NULL);
 661         dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
 662 }
 663
 664 static struct usb_driver ipheth_driver = {
 665         .name =         "ipheth",
 666         .probe =        ipheth_probe,
 667         .disconnect =   ipheth_disconnect,
 668         .id_table =     ipheth_table,
 669         .disable_hub_initiated_lpm = 1,
 670 };
 671
 672 module_usb_driver(ipheth_driver);
 673
 674 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
 675 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
 676 MODULE_LICENSE("Dual BSD/GPL");