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
  56 #define USB_VENDOR_APPLE        0x05ac
  57 #define USB_PRODUCT_IPHONE      0x1290
  58 #define USB_PRODUCT_IPHONE_3G   0x1292
  59 #define USB_PRODUCT_IPHONE_3GS  0x1294
  60 #define USB_PRODUCT_IPHONE_4    0x1297
  61 #define USB_PRODUCT_IPAD 0x129a
  62 #define USB_PRODUCT_IPAD_2      0x12a2
  63 #define USB_PRODUCT_IPAD_3      0x12a6
  64 #define USB_PRODUCT_IPAD_MINI    0x12ab
  65 #define USB_PRODUCT_IPHONE_4_VZW 0x129c
  66 #define USB_PRODUCT_IPHONE_4S   0x12a0
  67 #define USB_PRODUCT_IPHONE_5    0x12a8
  68
  69 #define IPHETH_USBINTF_CLASS    255
  70 #define IPHETH_USBINTF_SUBCLASS 253
  71 #define IPHETH_USBINTF_PROTO    1
  72
  73 #define IPHETH_BUF_SIZE         1516
  74 #define IPHETH_IP_ALIGN         2       /* padding at front of URB */
  75 #define IPHETH_TX_TIMEOUT       (5 * HZ)
  76
  77 #define IPHETH_INTFNUM          2
  78 #define IPHETH_ALT_INTFNUM      1
  79
  80 #define IPHETH_CTRL_ENDP        0x00
  81 #define IPHETH_CTRL_BUF_SIZE    0x40
  82 #define IPHETH_CTRL_TIMEOUT     (5 * HZ)
  83
  84 #define IPHETH_CMD_GET_MACADDR   0x00
  85 #define IPHETH_CMD_CARRIER_CHECK 0x45
  86
  87 #define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
  88 #define IPHETH_CARRIER_ON       0x04
  89
  90 static const struct usb_device_id ipheth_table[] = {
  91         { USB_DEVICE_AND_INTERFACE_INFO(
  92                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
  93                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
  94                 IPHETH_USBINTF_PROTO) },
  95         { USB_DEVICE_AND_INTERFACE_INFO(
  96                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3G,
  97                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
  98                 IPHETH_USBINTF_PROTO) },
  99         { USB_DEVICE_AND_INTERFACE_INFO(
 100                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_3GS,
 101                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 102                 IPHETH_USBINTF_PROTO) },
 103         { USB_DEVICE_AND_INTERFACE_INFO(
 104                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4,
 105                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 106                 IPHETH_USBINTF_PROTO) },
 107         { USB_DEVICE_AND_INTERFACE_INFO(
 108                 USB_VENDOR_APPLE, USB_PRODUCT_IPAD,
 109                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 110                 IPHETH_USBINTF_PROTO) },
 111         { USB_DEVICE_AND_INTERFACE_INFO(
 112                 USB_VENDOR_APPLE, USB_PRODUCT_IPAD_2,
 113                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 114                 IPHETH_USBINTF_PROTO) },
 115         { USB_DEVICE_AND_INTERFACE_INFO(
 116                 USB_VENDOR_APPLE, USB_PRODUCT_IPAD_3,
 117                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 118                 IPHETH_USBINTF_PROTO) },
 119         { USB_DEVICE_AND_INTERFACE_INFO(
 120                 USB_VENDOR_APPLE, USB_PRODUCT_IPAD_MINI,
 121                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 122                 IPHETH_USBINTF_PROTO) },
 123         { USB_DEVICE_AND_INTERFACE_INFO(
 124                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4_VZW,
 125                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 126                 IPHETH_USBINTF_PROTO) },
 127         { USB_DEVICE_AND_INTERFACE_INFO(
 128                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_4S,
 129                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 130                 IPHETH_USBINTF_PROTO) },
 131         { USB_DEVICE_AND_INTERFACE_INFO(
 132                 USB_VENDOR_APPLE, USB_PRODUCT_IPHONE_5,
 133                 IPHETH_USBINTF_CLASS, IPHETH_USBINTF_SUBCLASS,
 134                 IPHETH_USBINTF_PROTO) },
 135         { }
 136 };
 137 MODULE_DEVICE_TABLE(usb, ipheth_table);
 138
 139 struct ipheth_device {
 140         struct usb_device *udev;
 141         struct usb_interface *intf;
 142         struct net_device *net;
 143         struct sk_buff *tx_skb;
 144         struct urb *tx_urb;
 145         struct urb *rx_urb;
 146         unsigned char *tx_buf;
 147         unsigned char *rx_buf;
 148         unsigned char *ctrl_buf;
 149         u8 bulk_in;
 150         u8 bulk_out;
 151         struct delayed_work carrier_work;
 152         bool confirmed_pairing;
 153 };
 154
 155 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags);
 156
 157 static int ipheth_alloc_urbs(struct ipheth_device *iphone)
 158 {
 159         struct urb *tx_urb = NULL;
 160         struct urb *rx_urb = NULL;
 161         u8 *tx_buf = NULL;
 162         u8 *rx_buf = NULL;
 163
 164         tx_urb = usb_alloc_urb(0, GFP_KERNEL);
 165         if (tx_urb == NULL)
 166                 goto error_nomem;
 167
 168         rx_urb = usb_alloc_urb(0, GFP_KERNEL);
 169         if (rx_urb == NULL)
 170                 goto free_tx_urb;
 171
 172         tx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
 173                                     GFP_KERNEL, &tx_urb->transfer_dma);
 174         if (tx_buf == NULL)
 175                 goto free_rx_urb;
 176
 177         rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
 178                                     GFP_KERNEL, &rx_urb->transfer_dma);
 179         if (rx_buf == NULL)
 180                 goto free_tx_buf;
 181
 182
 183         iphone->tx_urb = tx_urb;
 184         iphone->rx_urb = rx_urb;
 185         iphone->tx_buf = tx_buf;
 186         iphone->rx_buf = rx_buf;
 187         return 0;
 188
 189 free_tx_buf:
 190         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, tx_buf,
 191                           tx_urb->transfer_dma);
 192 free_rx_urb:
 193         usb_free_urb(rx_urb);
 194 free_tx_urb:
 195         usb_free_urb(tx_urb);
 196 error_nomem:
 197         return -ENOMEM;
 198 }
 199
 200 static void ipheth_free_urbs(struct ipheth_device *iphone)
 201 {
 202         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
 203                           iphone->rx_urb->transfer_dma);
 204         usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
 205                           iphone->tx_urb->transfer_dma);
 206         usb_free_urb(iphone->rx_urb);
 207         usb_free_urb(iphone->tx_urb);
 208 }
 209
 210 static void ipheth_kill_urbs(struct ipheth_device *dev)
 211 {
 212         usb_kill_urb(dev->tx_urb);
 213         usb_kill_urb(dev->rx_urb);
 214 }
 215
 216 static void ipheth_rcvbulk_callback(struct urb *urb)
 217 {
 218         struct ipheth_device *dev;
 219         struct sk_buff *skb;
 220         int status;
 221         char *buf;
 222         int len;
 223
 224         dev = urb->context;
 225         if (dev == NULL)
 226                 return;
 227
 228         status = urb->status;
 229         switch (status) {
 230         case -ENOENT:
 231         case -ECONNRESET:
 232         case -ESHUTDOWN:
 233                 return;
 234         case 0:
 235                 break;
 236         default:
 237                 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
 238                         __func__, status);
 239                 return;
 240         }
 241
 242         if (urb->actual_length <= IPHETH_IP_ALIGN) {
 243                 dev->net->stats.rx_length_errors++;
 244                 return;
 245         }
 246         len = urb->actual_length - IPHETH_IP_ALIGN;
 247         buf = urb->transfer_buffer + IPHETH_IP_ALIGN;
 248
 249         skb = dev_alloc_skb(len);
 250         if (!skb) {
 251                 dev_err(&dev->intf->dev, "%s: dev_alloc_skb: -ENOMEM\n",
 252                         __func__);
 253                 dev->net->stats.rx_dropped++;
 254                 return;
 255         }
 256
 257         skb_put_data(skb, buf, len);
 258         skb->dev = dev->net;
 259         skb->protocol = eth_type_trans(skb, dev->net);
 260
 261         dev->net->stats.rx_packets++;
 262         dev->net->stats.rx_bytes += len;
 263         dev->confirmed_pairing = true;
 264         netif_rx(skb);
 265         ipheth_rx_submit(dev, GFP_ATOMIC);
 266 }
 267
 268 static void ipheth_sndbulk_callback(struct urb *urb)
 269 {
 270         struct ipheth_device *dev;
 271         int status = urb->status;
 272
 273         dev = urb->context;
 274         if (dev == NULL)
 275                 return;
 276
 277         if (status != 0 &&
 278             status != -ENOENT &&
 279             status != -ECONNRESET &&
 280             status != -ESHUTDOWN)
 281                 dev_err(&dev->intf->dev, "%s: urb status: %d\n",
 282                 __func__, status);
 283
 284         dev_kfree_skb_irq(dev->tx_skb);
 285         if (status == 0)
 286                 netif_wake_queue(dev->net);
 287         else
 288                 // on URB error, trigger immediate poll
 289                 schedule_delayed_work(&dev->carrier_work, 0);
 290 }
 291
 292 static int ipheth_carrier_set(struct ipheth_device *dev)
 293 {
 294         struct usb_device *udev;
 295         int retval;
 296
 297         if (!dev)
 298                 return 0;
 299         if (!dev->confirmed_pairing)
 300                 return 0;
 301
 302         udev = dev->udev;
 303         retval = usb_control_msg(udev,
 304                         usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
 305                         IPHETH_CMD_CARRIER_CHECK, /* request */
 306                         0xc0, /* request type */
 307                         0x00, /* value */
 308                         0x02, /* index */
 309                         dev->ctrl_buf, IPHETH_CTRL_BUF_SIZE,
 310                         IPHETH_CTRL_TIMEOUT);
 311         if (retval < 0) {
 312                 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
 313                         __func__, retval);
 314                 return retval;
 315         }
 316
 317         if (dev->ctrl_buf[0] == IPHETH_CARRIER_ON) {
 318                 netif_carrier_on(dev->net);
 319                 if (dev->tx_urb->status != -EINPROGRESS)
 320                         netif_wake_queue(dev->net);
 321         } else {
 322                 netif_carrier_off(dev->net);
 323                 netif_stop_queue(dev->net);
 324         }
 325         return 0;
 326 }
 327
 328 static void ipheth_carrier_check_work(struct work_struct *work)
 329 {
 330         struct ipheth_device *dev = container_of(work, struct ipheth_device,
 331                                                  carrier_work.work);
 332
 333         ipheth_carrier_set(dev);
 334         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
 335 }
 336
 337 static int ipheth_get_macaddr(struct ipheth_device *dev)
 338 {
 339         struct usb_device *udev = dev->udev;
 340         struct net_device *net = dev->net;
 341         int retval;
 342
 343         retval = usb_control_msg(udev,
 344                                  usb_rcvctrlpipe(udev, IPHETH_CTRL_ENDP),
 345                                  IPHETH_CMD_GET_MACADDR, /* request */
 346                                  0xc0, /* request type */
 347                                  0x00, /* value */
 348                                  0x02, /* index */
 349                                  dev->ctrl_buf,
 350                                  IPHETH_CTRL_BUF_SIZE,
 351                                  IPHETH_CTRL_TIMEOUT);
 352         if (retval < 0) {
 353                 dev_err(&dev->intf->dev, "%s: usb_control_msg: %d\n",
 354                         __func__, retval);
 355         } else if (retval < ETH_ALEN) {
 356                 dev_err(&dev->intf->dev,
 357                         "%s: usb_control_msg: short packet: %d bytes\n",
 358                         __func__, retval);
 359                 retval = -EINVAL;
 360         } else {
 361                 memcpy(net->dev_addr, dev->ctrl_buf, ETH_ALEN);
 362                 retval = 0;
 363         }
 364
 365         return retval;
 366 }
 367
 368 static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)
 369 {
 370         struct usb_device *udev = dev->udev;
 371         int retval;
 372
 373         usb_fill_bulk_urb(dev->rx_urb, udev,
 374                           usb_rcvbulkpipe(udev, dev->bulk_in),
 375                           dev->rx_buf, IPHETH_BUF_SIZE,
 376                           ipheth_rcvbulk_callback,
 377                           dev);
 378         dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 379
 380         retval = usb_submit_urb(dev->rx_urb, mem_flags);
 381         if (retval)
 382                 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
 383                         __func__, retval);
 384         return retval;
 385 }
 386
 387 static int ipheth_open(struct net_device *net)
 388 {
 389         struct ipheth_device *dev = netdev_priv(net);
 390         struct usb_device *udev = dev->udev;
 391         int retval = 0;
 392
 393         usb_set_interface(udev, IPHETH_INTFNUM, IPHETH_ALT_INTFNUM);
 394
 395         retval = ipheth_carrier_set(dev);
 396         if (retval)
 397                 return retval;
 398
 399         retval = ipheth_rx_submit(dev, GFP_KERNEL);
 400         if (retval)
 401                 return retval;
 402
 403         schedule_delayed_work(&dev->carrier_work, IPHETH_CARRIER_CHECK_TIMEOUT);
 404         return retval;
 405 }
 406
 407 static int ipheth_close(struct net_device *net)
 408 {
 409         struct ipheth_device *dev = netdev_priv(net);
 410
 411         cancel_delayed_work_sync(&dev->carrier_work);
 412         netif_stop_queue(net);
 413         return 0;
 414 }
 415
 416 static int ipheth_tx(struct sk_buff *skb, struct net_device *net)
 417 {
 418         struct ipheth_device *dev = netdev_priv(net);
 419         struct usb_device *udev = dev->udev;
 420         int retval;
 421
 422         /* Paranoid */
 423         if (skb->len > IPHETH_BUF_SIZE) {
 424                 WARN(1, "%s: skb too large: %d bytes\n", __func__, skb->len);
 425                 dev->net->stats.tx_dropped++;
 426                 dev_kfree_skb_irq(skb);
 427                 return NETDEV_TX_OK;
 428         }
 429
 430         memcpy(dev->tx_buf, skb->data, skb->len);
 431         if (skb->len < IPHETH_BUF_SIZE)
 432                 memset(dev->tx_buf + skb->len, 0, IPHETH_BUF_SIZE - skb->len);
 433
 434         usb_fill_bulk_urb(dev->tx_urb, udev,
 435                           usb_sndbulkpipe(udev, dev->bulk_out),
 436                           dev->tx_buf, IPHETH_BUF_SIZE,
 437                           ipheth_sndbulk_callback,
 438                           dev);
 439         dev->tx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 440
 441         retval = usb_submit_urb(dev->tx_urb, GFP_ATOMIC);
 442         if (retval) {
 443                 dev_err(&dev->intf->dev, "%s: usb_submit_urb: %d\n",
 444                         __func__, retval);
 445                 dev->net->stats.tx_errors++;
 446                 dev_kfree_skb_irq(skb);
 447         } else {
 448                 dev->tx_skb = skb;
 449
 450                 dev->net->stats.tx_packets++;
 451                 dev->net->stats.tx_bytes += skb->len;
 452                 netif_stop_queue(net);
 453         }
 454
 455         return NETDEV_TX_OK;
 456 }
 457
 458 static void ipheth_tx_timeout(struct net_device *net)
 459 {
 460         struct ipheth_device *dev = netdev_priv(net);
 461
 462         dev_err(&dev->intf->dev, "%s: TX timeout\n", __func__);
 463         dev->net->stats.tx_errors++;
 464         usb_unlink_urb(dev->tx_urb);
 465 }
 466
 467 static u32 ipheth_ethtool_op_get_link(struct net_device *net)
 468 {
 469         struct ipheth_device *dev = netdev_priv(net);
 470         return netif_carrier_ok(dev->net);
 471 }
 472
 473 static const struct ethtool_ops ops = {
 474         .get_link = ipheth_ethtool_op_get_link
 475 };
 476
 477 static const struct net_device_ops ipheth_netdev_ops = {
 478         .ndo_open = ipheth_open,
 479         .ndo_stop = ipheth_close,
 480         .ndo_start_xmit = ipheth_tx,
 481         .ndo_tx_timeout = ipheth_tx_timeout,
 482 };
 483
 484 static int ipheth_probe(struct usb_interface *intf,
 485                         const struct usb_device_id *id)
 486 {
 487         struct usb_device *udev = interface_to_usbdev(intf);
 488         struct usb_host_interface *hintf;
 489         struct usb_endpoint_descriptor *endp;
 490         struct ipheth_device *dev;
 491         struct net_device *netdev;
 492         int i;
 493         int retval;
 494
 495         netdev = alloc_etherdev(sizeof(struct ipheth_device));
 496         if (!netdev)
 497                 return -ENOMEM;
 498
 499         netdev->netdev_ops = &ipheth_netdev_ops;
 500         netdev->watchdog_timeo = IPHETH_TX_TIMEOUT;
 501         strcpy(netdev->name, "eth%d");
 502
 503         dev = netdev_priv(netdev);
 504         dev->udev = udev;
 505         dev->net = netdev;
 506         dev->intf = intf;
 507         dev->confirmed_pairing = false;
 508         /* Set up endpoints */
 509         hintf = usb_altnum_to_altsetting(intf, IPHETH_ALT_INTFNUM);
 510         if (hintf == NULL) {
 511                 retval = -ENODEV;
 512                 dev_err(&intf->dev, "Unable to find alternate settings interface\n");
 513                 goto err_endpoints;
 514         }
 515
 516         for (i = 0; i < hintf->desc.bNumEndpoints; i++) {
 517                 endp = &hintf->endpoint[i].desc;
 518                 if (usb_endpoint_is_bulk_in(endp))
 519                         dev->bulk_in = endp->bEndpointAddress;
 520                 else if (usb_endpoint_is_bulk_out(endp))
 521                         dev->bulk_out = endp->bEndpointAddress;
 522         }
 523         if (!(dev->bulk_in && dev->bulk_out)) {
 524                 retval = -ENODEV;
 525                 dev_err(&intf->dev, "Unable to find endpoints\n");
 526                 goto err_endpoints;
 527         }
 528
 529         dev->ctrl_buf = kmalloc(IPHETH_CTRL_BUF_SIZE, GFP_KERNEL);
 530         if (dev->ctrl_buf == NULL) {
 531                 retval = -ENOMEM;
 532                 goto err_alloc_ctrl_buf;
 533         }
 534
 535         retval = ipheth_get_macaddr(dev);
 536         if (retval)
 537                 goto err_get_macaddr;
 538
 539         INIT_DELAYED_WORK(&dev->carrier_work, ipheth_carrier_check_work);
 540
 541         retval = ipheth_alloc_urbs(dev);
 542         if (retval) {
 543                 dev_err(&intf->dev, "error allocating urbs: %d\n", retval);
 544                 goto err_alloc_urbs;
 545         }
 546
 547         usb_set_intfdata(intf, dev);
 548
 549         SET_NETDEV_DEV(netdev, &intf->dev);
 550         netdev->ethtool_ops = &ops;
 551
 552         retval = register_netdev(netdev);
 553         if (retval) {
 554                 dev_err(&intf->dev, "error registering netdev: %d\n", retval);
 555                 retval = -EIO;
 556                 goto err_register_netdev;
 557         }
 558         // carrier down and transmit queues stopped until packet from device
 559         netif_carrier_off(netdev);
 560         netif_tx_stop_all_queues(netdev);
 561         dev_info(&intf->dev, "Apple iPhone USB Ethernet device attached\n");
 562         return 0;
 563
 564 err_register_netdev:
 565         ipheth_free_urbs(dev);
 566 err_alloc_urbs:
 567 err_get_macaddr:
 568 err_alloc_ctrl_buf:
 569         kfree(dev->ctrl_buf);
 570 err_endpoints:
 571         free_netdev(netdev);
 572         return retval;
 573 }
 574
 575 static void ipheth_disconnect(struct usb_interface *intf)
 576 {
 577         struct ipheth_device *dev;
 578
 579         dev = usb_get_intfdata(intf);
 580         if (dev != NULL) {
 581                 unregister_netdev(dev->net);
 582                 ipheth_kill_urbs(dev);
 583                 ipheth_free_urbs(dev);
 584                 kfree(dev->ctrl_buf);
 585                 free_netdev(dev->net);
 586         }
 587         usb_set_intfdata(intf, NULL);
 588         dev_info(&intf->dev, "Apple iPhone USB Ethernet now disconnected\n");
 589 }
 590
 591 static struct usb_driver ipheth_driver = {
 592         .name =         "ipheth",
 593         .probe =        ipheth_probe,
 594         .disconnect =   ipheth_disconnect,
 595         .id_table =     ipheth_table,
 596         .disable_hub_initiated_lpm = 1,
 597 };
 598
 599 module_usb_driver(ipheth_driver);
 600
 601 MODULE_AUTHOR("Diego Giagio <diego@giagio.com>");
 602 MODULE_DESCRIPTION("Apple iPhone USB Ethernet driver");
 603 MODULE_LICENSE("Dual BSD/GPL");