drivers/net/usb/usbnet.c

   1 /*
   2  * USB Network driver infrastructure
   3  * Copyright (C) 2000-2005 by David Brownell
   4  * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  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  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 /*
  22  * This is a generic "USB networking" framework that works with several
  23  * kinds of full and high speed networking devices:  host-to-host cables,
  24  * smart usb peripherals, and actual Ethernet adapters.
  25  *
  26  * These devices usually differ in terms of control protocols (if they
  27  * even have one!) and sometimes they define new framing to wrap or batch
  28  * Ethernet packets.  Otherwise, they talk to USB pretty much the same,
  29  * so interface (un)binding, endpoint I/O queues, fault handling, and other
  30  * issues can usefully be addressed by this framework.
  31  */
  32
  33 // #define      DEBUG                   // error path messages, extra info
  34 // #define      VERBOSE                 // more; success messages
  35
  36 #include <linux/module.h>
  37 #include <linux/init.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/etherdevice.h>
  40 #include <linux/ctype.h>
  41 #include <linux/ethtool.h>
  42 #include <linux/workqueue.h>
  43 #include <linux/mii.h>
  44 #include <linux/usb.h>
  45 #include <linux/usb/usbnet.h>
  46
  47 #define DRIVER_VERSION          "22-Aug-2005"
  48
  49
  50 /*-------------------------------------------------------------------------*/
  51
  52 /*
  53  * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  54  * Several dozen bytes of IPv4 data can fit in two such transactions.
  55  * One maximum size Ethernet packet takes twenty four of them.
  56  * For high speed, each frame comfortably fits almost 36 max size
  57  * Ethernet packets (so queues should be bigger).
  58  *
  59  * REVISIT qlens should be members of 'struct usbnet'; the goal is to
  60  * let the USB host controller be busy for 5msec or more before an irq
  61  * is required, under load.  Jumbograms change the equation.
  62  */
  63 #define RX_MAX_QUEUE_MEMORY (60 * 1518)
  64 #define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  65                         (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
  66 #define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  67                         (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
  68
  69 // reawaken network queue this soon after stopping; else watchdog barks
  70 #define TX_TIMEOUT_JIFFIES      (5*HZ)
  71
  72 // throttle rx/tx briefly after some faults, so khubd might disconnect()
  73 // us (it polls at HZ/4 usually) before we report too many false errors.
  74 #define THROTTLE_JIFFIES        (HZ/8)
  75
  76 // between wakeups
  77 #define UNLINK_TIMEOUT_MS       3
  78
  79 /*-------------------------------------------------------------------------*/
  80
  81 // randomly generated ethernet address
  82 static u8       node_id [ETH_ALEN];
  83
  84 static const char driver_name [] = "usbnet";
  85
  86 /* use ethtool to change the level for any given device */
  87 static int msg_level = -1;
  88 module_param (msg_level, int, 0);
  89 MODULE_PARM_DESC (msg_level, "Override default message level");
  90
  91 /*-------------------------------------------------------------------------*/
  92
  93 /* handles CDC Ethernet and many other network "bulk data" interfaces */
  94 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  95 {
  96         int                             tmp;
  97         struct usb_host_interface       *alt = NULL;
  98         struct usb_host_endpoint        *in = NULL, *out = NULL;
  99         struct usb_host_endpoint        *status = NULL;
 100
 101         for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 102                 unsigned        ep;
 103
 104                 in = out = status = NULL;
 105                 alt = intf->altsetting + tmp;
 106
 107                 /* take the first altsetting with in-bulk + out-bulk;
 108                  * remember any status endpoint, just in case;
 109                  * ignore other endpoints and altsetttings.
 110                  */
 111                 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 112                         struct usb_host_endpoint        *e;
 113                         int                             intr = 0;
 114
 115                         e = alt->endpoint + ep;
 116                         switch (e->desc.bmAttributes) {
 117                         case USB_ENDPOINT_XFER_INT:
 118                                 if (!usb_endpoint_dir_in(&e->desc))
 119                                         continue;
 120                                 intr = 1;
 121                                 /* FALLTHROUGH */
 122                         case USB_ENDPOINT_XFER_BULK:
 123                                 break;
 124                         default:
 125                                 continue;
 126                         }
 127                         if (usb_endpoint_dir_in(&e->desc)) {
 128                                 if (!intr && !in)
 129                                         in = e;
 130                                 else if (intr && !status)
 131                                         status = e;
 132                         } else {
 133                                 if (!out)
 134                                         out = e;
 135                         }
 136                 }
 137                 if (in && out)
 138                         break;
 139         }
 140         if (!alt || !in || !out)
 141                 return -EINVAL;
 142
 143         if (alt->desc.bAlternateSetting != 0
 144                         || !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 145                 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 146                                 alt->desc.bAlternateSetting);
 147                 if (tmp < 0)
 148                         return tmp;
 149         }
 150
 151         dev->in = usb_rcvbulkpipe (dev->udev,
 152                         in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 153         dev->out = usb_sndbulkpipe (dev->udev,
 154                         out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 155         dev->status = status;
 156         return 0;
 157 }
 158 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 159
 160 static u8 nibble(unsigned char c)
 161 {
 162         if (likely(isdigit(c)))
 163                 return c - '0';
 164         c = toupper(c);
 165         if (likely(isxdigit(c)))
 166                 return 10 + c - 'A';
 167         return 0;
 168 }
 169
 170 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 171 {
 172         int             tmp, i;
 173         unsigned char   buf [13];
 174
 175         tmp = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 176         if (tmp != 12) {
 177                 dev_dbg(&dev->udev->dev,
 178                         "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 179                 if (tmp >= 0)
 180                         tmp = -EINVAL;
 181                 return tmp;
 182         }
 183         for (i = tmp = 0; i < 6; i++, tmp += 2)
 184                 dev->net->dev_addr [i] =
 185                         (nibble(buf [tmp]) << 4) + nibble(buf [tmp + 1]);
 186         return 0;
 187 }
 188 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 189
 190 static void intr_complete (struct urb *urb);
 191
 192 static int init_status (struct usbnet *dev, struct usb_interface *intf)
 193 {
 194         char            *buf = NULL;
 195         unsigned        pipe = 0;
 196         unsigned        maxp;
 197         unsigned        period;
 198
 199         if (!dev->driver_info->status)
 200                 return 0;
 201
 202         pipe = usb_rcvintpipe (dev->udev,
 203                         dev->status->desc.bEndpointAddress
 204                                 & USB_ENDPOINT_NUMBER_MASK);
 205         maxp = usb_maxpacket (dev->udev, pipe, 0);
 206
 207         /* avoid 1 msec chatter:  min 8 msec poll rate */
 208         period = max ((int) dev->status->desc.bInterval,
 209                 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 210
 211         buf = kmalloc (maxp, GFP_KERNEL);
 212         if (buf) {
 213                 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 214                 if (!dev->interrupt) {
 215                         kfree (buf);
 216                         return -ENOMEM;
 217                 } else {
 218                         usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 219                                 buf, maxp, intr_complete, dev, period);
 220                         dev_dbg(&intf->dev,
 221                                 "status ep%din, %d bytes period %d\n",
 222                                 usb_pipeendpoint(pipe), maxp, period);
 223                 }
 224         }
 225         return 0;
 226 }
 227
 228 /* Passes this packet up the stack, updating its accounting.
 229  * Some link protocols batch packets, so their rx_fixup paths
 230  * can return clones as well as just modify the original skb.
 231  */
 232 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 233 {
 234         int     status;
 235
 236         skb->protocol = eth_type_trans (skb, dev->net);
 237         dev->net->stats.rx_packets++;
 238         dev->net->stats.rx_bytes += skb->len;
 239
 240         if (netif_msg_rx_status (dev))
 241                 devdbg (dev, "< rx, len %zu, type 0x%x",
 242                         skb->len + sizeof (struct ethhdr), skb->protocol);
 243         memset (skb->cb, 0, sizeof (struct skb_data));
 244         status = netif_rx (skb);
 245         if (status != NET_RX_SUCCESS && netif_msg_rx_err (dev))
 246                 devdbg (dev, "netif_rx status %d", status);
 247 }
 248 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 249
 250 \f
 251 /*-------------------------------------------------------------------------
 252  *
 253  * Network Device Driver (peer link to "Host Device", from USB host)
 254  *
 255  *-------------------------------------------------------------------------*/
 256
 257 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 258 {
 259         struct usbnet   *dev = netdev_priv(net);
 260         int             ll_mtu = new_mtu + net->hard_header_len;
 261         int             old_hard_mtu = dev->hard_mtu;
 262         int             old_rx_urb_size = dev->rx_urb_size;
 263
 264         if (new_mtu <= 0)
 265                 return -EINVAL;
 266         // no second zero-length packet read wanted after mtu-sized packets
 267         if ((ll_mtu % dev->maxpacket) == 0)
 268                 return -EDOM;
 269         net->mtu = new_mtu;
 270
 271         dev->hard_mtu = net->mtu + net->hard_header_len;
 272         if (dev->rx_urb_size == old_hard_mtu) {
 273                 dev->rx_urb_size = dev->hard_mtu;
 274                 if (dev->rx_urb_size > old_rx_urb_size)
 275                         usbnet_unlink_rx_urbs(dev);
 276         }
 277
 278         return 0;
 279 }
 280 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 281
 282 /*-------------------------------------------------------------------------*/
 283
 284 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 285  * completion callbacks.  2.5 should have fixed those bugs...
 286  */
 287
 288 static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 289 {
 290         unsigned long           flags;
 291
 292         spin_lock_irqsave(&list->lock, flags);
 293         __skb_unlink(skb, list);
 294         spin_unlock(&list->lock);
 295         spin_lock(&dev->done.lock);
 296         __skb_queue_tail(&dev->done, skb);
 297         if (dev->done.qlen == 1)
 298                 tasklet_schedule(&dev->bh);
 299         spin_unlock_irqrestore(&dev->done.lock, flags);
 300 }
 301
 302 /* some work can't be done in tasklets, so we use keventd
 303  *
 304  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 305  * but tasklet_schedule() doesn't.  hope the failure is rare.
 306  */
 307 void usbnet_defer_kevent (struct usbnet *dev, int work)
 308 {
 309         set_bit (work, &dev->flags);
 310         if (!schedule_work (&dev->kevent))
 311                 deverr (dev, "kevent %d may have been dropped", work);
 312         else
 313                 devdbg (dev, "kevent %d scheduled", work);
 314 }
 315 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 316
 317 /*-------------------------------------------------------------------------*/
 318
 319 static void rx_complete (struct urb *urb);
 320
 321 static void rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 322 {
 323         struct sk_buff          *skb;
 324         struct skb_data         *entry;
 325         int                     retval = 0;
 326         unsigned long           lockflags;
 327         size_t                  size = dev->rx_urb_size;
 328
 329         if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
 330                 if (netif_msg_rx_err (dev))
 331                         devdbg (dev, "no rx skb");
 332                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 333                 usb_free_urb (urb);
 334                 return;
 335         }
 336         skb_reserve (skb, NET_IP_ALIGN);
 337
 338         entry = (struct skb_data *) skb->cb;
 339         entry->urb = urb;
 340         entry->dev = dev;
 341         entry->state = rx_start;
 342         entry->length = 0;
 343
 344         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 345                 skb->data, size, rx_complete, skb);
 346
 347         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 348
 349         if (netif_running (dev->net)
 350                         && netif_device_present (dev->net)
 351                         && !test_bit (EVENT_RX_HALT, &dev->flags)) {
 352                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 353                 case -EPIPE:
 354                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 355                         break;
 356                 case -ENOMEM:
 357                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 358                         break;
 359                 case -ENODEV:
 360                         if (netif_msg_ifdown (dev))
 361                                 devdbg (dev, "device gone");
 362                         netif_device_detach (dev->net);
 363                         break;
 364                 default:
 365                         if (netif_msg_rx_err (dev))
 366                                 devdbg (dev, "rx submit, %d", retval);
 367                         tasklet_schedule (&dev->bh);
 368                         break;
 369                 case 0:
 370                         __skb_queue_tail (&dev->rxq, skb);
 371                 }
 372         } else {
 373                 if (netif_msg_ifdown (dev))
 374                         devdbg (dev, "rx: stopped");
 375                 retval = -ENOLINK;
 376         }
 377         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 378         if (retval) {
 379                 dev_kfree_skb_any (skb);
 380                 usb_free_urb (urb);
 381         }
 382 }
 383
 384
 385 /*-------------------------------------------------------------------------*/
 386
 387 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 388 {
 389         if (dev->driver_info->rx_fixup
 390                         && !dev->driver_info->rx_fixup (dev, skb))
 391                 goto error;
 392         // else network stack removes extra byte if we forced a short packet
 393
 394         if (skb->len)
 395                 usbnet_skb_return (dev, skb);
 396         else {
 397                 if (netif_msg_rx_err (dev))
 398                         devdbg (dev, "drop");
 399 error:
 400                 dev->net->stats.rx_errors++;
 401                 skb_queue_tail (&dev->done, skb);
 402         }
 403 }
 404
 405 /*-------------------------------------------------------------------------*/
 406
 407 static void rx_complete (struct urb *urb)
 408 {
 409         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 410         struct skb_data         *entry = (struct skb_data *) skb->cb;
 411         struct usbnet           *dev = entry->dev;
 412         int                     urb_status = urb->status;
 413
 414         skb_put (skb, urb->actual_length);
 415         entry->state = rx_done;
 416         entry->urb = NULL;
 417
 418         switch (urb_status) {
 419         /* success */
 420         case 0:
 421                 if (skb->len < dev->net->hard_header_len) {
 422                         entry->state = rx_cleanup;
 423                         dev->net->stats.rx_errors++;
 424                         dev->net->stats.rx_length_errors++;
 425                         if (netif_msg_rx_err (dev))
 426                                 devdbg (dev, "rx length %d", skb->len);
 427                 }
 428                 break;
 429
 430         /* stalls need manual reset. this is rare ... except that
 431          * when going through USB 2.0 TTs, unplug appears this way.
 432          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 433          * storm, recovering as needed.
 434          */
 435         case -EPIPE:
 436                 dev->net->stats.rx_errors++;
 437                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 438                 // FALLTHROUGH
 439
 440         /* software-driven interface shutdown */
 441         case -ECONNRESET:               /* async unlink */
 442         case -ESHUTDOWN:                /* hardware gone */
 443                 if (netif_msg_ifdown (dev))
 444                         devdbg (dev, "rx shutdown, code %d", urb_status);
 445                 goto block;
 446
 447         /* we get controller i/o faults during khubd disconnect() delays.
 448          * throttle down resubmits, to avoid log floods; just temporarily,
 449          * so we still recover when the fault isn't a khubd delay.
 450          */
 451         case -EPROTO:
 452         case -ETIME:
 453         case -EILSEQ:
 454                 dev->net->stats.rx_errors++;
 455                 if (!timer_pending (&dev->delay)) {
 456                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 457                         if (netif_msg_link (dev))
 458                                 devdbg (dev, "rx throttle %d", urb_status);
 459                 }
 460 block:
 461                 entry->state = rx_cleanup;
 462                 entry->urb = urb;
 463                 urb = NULL;
 464                 break;
 465
 466         /* data overrun ... flush fifo? */
 467         case -EOVERFLOW:
 468                 dev->net->stats.rx_over_errors++;
 469                 // FALLTHROUGH
 470
 471         default:
 472                 entry->state = rx_cleanup;
 473                 dev->net->stats.rx_errors++;
 474                 if (netif_msg_rx_err (dev))
 475                         devdbg (dev, "rx status %d", urb_status);
 476                 break;
 477         }
 478
 479         defer_bh(dev, skb, &dev->rxq);
 480
 481         if (urb) {
 482                 if (netif_running (dev->net)
 483                                 && !test_bit (EVENT_RX_HALT, &dev->flags)) {
 484                         rx_submit (dev, urb, GFP_ATOMIC);
 485                         return;
 486                 }
 487                 usb_free_urb (urb);
 488         }
 489         if (netif_msg_rx_err (dev))
 490                 devdbg (dev, "no read resubmitted");
 491 }
 492
 493 static void intr_complete (struct urb *urb)
 494 {
 495         struct usbnet   *dev = urb->context;
 496         int             status = urb->status;
 497
 498         switch (status) {
 499         /* success */
 500         case 0:
 501                 dev->driver_info->status(dev, urb);
 502                 break;
 503
 504         /* software-driven interface shutdown */
 505         case -ENOENT:           /* urb killed */
 506         case -ESHUTDOWN:        /* hardware gone */
 507                 if (netif_msg_ifdown (dev))
 508                         devdbg (dev, "intr shutdown, code %d", status);
 509                 return;
 510
 511         /* NOTE:  not throttling like RX/TX, since this endpoint
 512          * already polls infrequently
 513          */
 514         default:
 515                 devdbg (dev, "intr status %d", status);
 516                 break;
 517         }
 518
 519         if (!netif_running (dev->net))
 520                 return;
 521
 522         memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 523         status = usb_submit_urb (urb, GFP_ATOMIC);
 524         if (status != 0 && netif_msg_timer (dev))
 525                 deverr(dev, "intr resubmit --> %d", status);
 526 }
 527
 528 /*-------------------------------------------------------------------------*/
 529
 530 // unlink pending rx/tx; completion handlers do all other cleanup
 531
 532 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 533 {
 534         unsigned long           flags;
 535         struct sk_buff          *skb, *skbnext;
 536         int                     count = 0;
 537
 538         spin_lock_irqsave (&q->lock, flags);
 539         skb_queue_walk_safe(q, skb, skbnext) {
 540                 struct skb_data         *entry;
 541                 struct urb              *urb;
 542                 int                     retval;
 543
 544                 entry = (struct skb_data *) skb->cb;
 545                 urb = entry->urb;
 546
 547                 // during some PM-driven resume scenarios,
 548                 // these (async) unlinks complete immediately
 549                 retval = usb_unlink_urb (urb);
 550                 if (retval != -EINPROGRESS && retval != 0)
 551                         devdbg (dev, "unlink urb err, %d", retval);
 552                 else
 553                         count++;
 554         }
 555         spin_unlock_irqrestore (&q->lock, flags);
 556         return count;
 557 }
 558
 559 // Flush all pending rx urbs
 560 // minidrivers may need to do this when the MTU changes
 561
 562 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 563 {
 564         if (netif_running(dev->net)) {
 565                 (void) unlink_urbs (dev, &dev->rxq);
 566                 tasklet_schedule(&dev->bh);
 567         }
 568 }
 569 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 570
 571 /*-------------------------------------------------------------------------*/
 572
 573 // precondition: never called in_interrupt
 574
 575 int usbnet_stop (struct net_device *net)
 576 {
 577         struct usbnet           *dev = netdev_priv(net);
 578         int                     temp;
 579         DECLARE_WAIT_QUEUE_HEAD_ONSTACK (unlink_wakeup);
 580         DECLARE_WAITQUEUE (wait, current);
 581
 582         netif_stop_queue (net);
 583
 584         if (netif_msg_ifdown (dev))
 585                 devinfo (dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld",
 586                         net->stats.rx_packets, net->stats.tx_packets,
 587                         net->stats.rx_errors, net->stats.tx_errors
 588                         );
 589
 590         // ensure there are no more active urbs
 591         add_wait_queue (&unlink_wakeup, &wait);
 592         dev->wait = &unlink_wakeup;
 593         temp = unlink_urbs (dev, &dev->txq) + unlink_urbs (dev, &dev->rxq);
 594
 595         // maybe wait for deletions to finish.
 596         while (!skb_queue_empty(&dev->rxq)
 597                         && !skb_queue_empty(&dev->txq)
 598                         && !skb_queue_empty(&dev->done)) {
 599                 msleep(UNLINK_TIMEOUT_MS);
 600                 if (netif_msg_ifdown (dev))
 601                         devdbg (dev, "waited for %d urb completions", temp);
 602         }
 603         dev->wait = NULL;
 604         remove_wait_queue (&unlink_wakeup, &wait);
 605
 606         usb_kill_urb(dev->interrupt);
 607
 608         /* deferred work (task, timer, softirq) must also stop.
 609          * can't flush_scheduled_work() until we drop rtnl (later),
 610          * else workers could deadlock; so make workers a NOP.
 611          */
 612         dev->flags = 0;
 613         del_timer_sync (&dev->delay);
 614         tasklet_kill (&dev->bh);
 615         usb_autopm_put_interface(dev->intf);
 616
 617         return 0;
 618 }
 619 EXPORT_SYMBOL_GPL(usbnet_stop);
 620
 621 /*-------------------------------------------------------------------------*/
 622
 623 // posts reads, and enables write queuing
 624
 625 // precondition: never called in_interrupt
 626
 627 int usbnet_open (struct net_device *net)
 628 {
 629         struct usbnet           *dev = netdev_priv(net);
 630         int                     retval;
 631         struct driver_info      *info = dev->driver_info;
 632
 633         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 634                 if (netif_msg_ifup (dev))
 635                         devinfo (dev,
 636                                 "resumption fail (%d) usbnet usb-%s-%s, %s",
 637                                 retval,
 638                                 dev->udev->bus->bus_name, dev->udev->devpath,
 639                         info->description);
 640                 goto done_nopm;
 641         }
 642
 643         // put into "known safe" state
 644         if (info->reset && (retval = info->reset (dev)) < 0) {
 645                 if (netif_msg_ifup (dev))
 646                         devinfo (dev,
 647                                 "open reset fail (%d) usbnet usb-%s-%s, %s",
 648                                 retval,
 649                                 dev->udev->bus->bus_name, dev->udev->devpath,
 650                         info->description);
 651                 goto done;
 652         }
 653
 654         // insist peer be connected
 655         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 656                 if (netif_msg_ifup (dev))
 657                         devdbg (dev, "can't open; %d", retval);
 658                 goto done;
 659         }
 660
 661         /* start any status interrupt transfer */
 662         if (dev->interrupt) {
 663                 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 664                 if (retval < 0) {
 665                         if (netif_msg_ifup (dev))
 666                                 deverr (dev, "intr submit %d", retval);
 667                         goto done;
 668                 }
 669         }
 670
 671         netif_start_queue (net);
 672         if (netif_msg_ifup (dev)) {
 673                 char    *framing;
 674
 675                 if (dev->driver_info->flags & FLAG_FRAMING_NC)
 676                         framing = "NetChip";
 677                 else if (dev->driver_info->flags & FLAG_FRAMING_GL)
 678                         framing = "GeneSys";
 679                 else if (dev->driver_info->flags & FLAG_FRAMING_Z)
 680                         framing = "Zaurus";
 681                 else if (dev->driver_info->flags & FLAG_FRAMING_RN)
 682                         framing = "RNDIS";
 683                 else if (dev->driver_info->flags & FLAG_FRAMING_AX)
 684                         framing = "ASIX";
 685                 else
 686                         framing = "simple";
 687
 688                 devinfo (dev, "open: enable queueing "
 689                                 "(rx %d, tx %d) mtu %d %s framing",
 690                         (int)RX_QLEN (dev), (int)TX_QLEN (dev), dev->net->mtu,
 691                         framing);
 692         }
 693
 694         // delay posting reads until we're fully open
 695         tasklet_schedule (&dev->bh);
 696         return retval;
 697 done:
 698         usb_autopm_put_interface(dev->intf);
 699 done_nopm:
 700         return retval;
 701 }
 702 EXPORT_SYMBOL_GPL(usbnet_open);
 703
 704 /*-------------------------------------------------------------------------*/
 705
 706 /* ethtool methods; minidrivers may need to add some more, but
 707  * they'll probably want to use this base set.
 708  */
 709
 710 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 711 {
 712         struct usbnet *dev = netdev_priv(net);
 713
 714         if (!dev->mii.mdio_read)
 715                 return -EOPNOTSUPP;
 716
 717         return mii_ethtool_gset(&dev->mii, cmd);
 718 }
 719 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 720
 721 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 722 {
 723         struct usbnet *dev = netdev_priv(net);
 724         int retval;
 725
 726         if (!dev->mii.mdio_write)
 727                 return -EOPNOTSUPP;
 728
 729         retval = mii_ethtool_sset(&dev->mii, cmd);
 730
 731         /* link speed/duplex might have changed */
 732         if (dev->driver_info->link_reset)
 733                 dev->driver_info->link_reset(dev);
 734
 735         return retval;
 736
 737 }
 738 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 739
 740 u32 usbnet_get_link (struct net_device *net)
 741 {
 742         struct usbnet *dev = netdev_priv(net);
 743
 744         /* If a check_connect is defined, return its result */
 745         if (dev->driver_info->check_connect)
 746                 return dev->driver_info->check_connect (dev) == 0;
 747
 748         /* if the device has mii operations, use those */
 749         if (dev->mii.mdio_read)
 750                 return mii_link_ok(&dev->mii);
 751
 752         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 753         return ethtool_op_get_link(net);
 754 }
 755 EXPORT_SYMBOL_GPL(usbnet_get_link);
 756
 757 int usbnet_nway_reset(struct net_device *net)
 758 {
 759         struct usbnet *dev = netdev_priv(net);
 760
 761         if (!dev->mii.mdio_write)
 762                 return -EOPNOTSUPP;
 763
 764         return mii_nway_restart(&dev->mii);
 765 }
 766 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 767
 768 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 769 {
 770         struct usbnet *dev = netdev_priv(net);
 771
 772         strncpy (info->driver, dev->driver_name, sizeof info->driver);
 773         strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 774         strncpy (info->fw_version, dev->driver_info->description,
 775                 sizeof info->fw_version);
 776         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 777 }
 778 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 779
 780 u32 usbnet_get_msglevel (struct net_device *net)
 781 {
 782         struct usbnet *dev = netdev_priv(net);
 783
 784         return dev->msg_enable;
 785 }
 786 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 787
 788 void usbnet_set_msglevel (struct net_device *net, u32 level)
 789 {
 790         struct usbnet *dev = netdev_priv(net);
 791
 792         dev->msg_enable = level;
 793 }
 794 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 795
 796 /* drivers may override default ethtool_ops in their bind() routine */
 797 static struct ethtool_ops usbnet_ethtool_ops = {
 798         .get_settings           = usbnet_get_settings,
 799         .set_settings           = usbnet_set_settings,
 800         .get_link               = usbnet_get_link,
 801         .nway_reset             = usbnet_nway_reset,
 802         .get_drvinfo            = usbnet_get_drvinfo,
 803         .get_msglevel           = usbnet_get_msglevel,
 804         .set_msglevel           = usbnet_set_msglevel,
 805 };
 806
 807 /*-------------------------------------------------------------------------*/
 808
 809 /* work that cannot be done in interrupt context uses keventd.
 810  *
 811  * NOTE:  with 2.5 we could do more of this using completion callbacks,
 812  * especially now that control transfers can be queued.
 813  */
 814 static void
 815 kevent (struct work_struct *work)
 816 {
 817         struct usbnet           *dev =
 818                 container_of(work, struct usbnet, kevent);
 819         int                     status;
 820
 821         /* usb_clear_halt() needs a thread context */
 822         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 823                 unlink_urbs (dev, &dev->txq);
 824                 status = usb_clear_halt (dev->udev, dev->out);
 825                 if (status < 0
 826                                 && status != -EPIPE
 827                                 && status != -ESHUTDOWN) {
 828                         if (netif_msg_tx_err (dev))
 829                                 deverr (dev, "can't clear tx halt, status %d",
 830                                         status);
 831                 } else {
 832                         clear_bit (EVENT_TX_HALT, &dev->flags);
 833                         if (status != -ESHUTDOWN)
 834                                 netif_wake_queue (dev->net);
 835                 }
 836         }
 837         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 838                 unlink_urbs (dev, &dev->rxq);
 839                 status = usb_clear_halt (dev->udev, dev->in);
 840                 if (status < 0
 841                                 && status != -EPIPE
 842                                 && status != -ESHUTDOWN) {
 843                         if (netif_msg_rx_err (dev))
 844                                 deverr (dev, "can't clear rx halt, status %d",
 845                                         status);
 846                 } else {
 847                         clear_bit (EVENT_RX_HALT, &dev->flags);
 848                         tasklet_schedule (&dev->bh);
 849                 }
 850         }
 851
 852         /* tasklet could resubmit itself forever if memory is tight */
 853         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 854                 struct urb      *urb = NULL;
 855
 856                 if (netif_running (dev->net))
 857                         urb = usb_alloc_urb (0, GFP_KERNEL);
 858                 else
 859                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 860                 if (urb != NULL) {
 861                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 862                         rx_submit (dev, urb, GFP_KERNEL);
 863                         tasklet_schedule (&dev->bh);
 864                 }
 865         }
 866
 867         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 868                 struct driver_info      *info = dev->driver_info;
 869                 int                     retval = 0;
 870
 871                 clear_bit (EVENT_LINK_RESET, &dev->flags);
 872                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 873                         devinfo(dev, "link reset failed (%d) usbnet usb-%s-%s, %s",
 874                                 retval,
 875                                 dev->udev->bus->bus_name, dev->udev->devpath,
 876                                 info->description);
 877                 }
 878         }
 879
 880         if (dev->flags)
 881                 devdbg (dev, "kevent done, flags = 0x%lx",
 882                         dev->flags);
 883 }
 884
 885 /*-------------------------------------------------------------------------*/
 886
 887 static void tx_complete (struct urb *urb)
 888 {
 889         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 890         struct skb_data         *entry = (struct skb_data *) skb->cb;
 891         struct usbnet           *dev = entry->dev;
 892
 893         if (urb->status == 0) {
 894                 dev->net->stats.tx_packets++;
 895                 dev->net->stats.tx_bytes += entry->length;
 896         } else {
 897                 dev->net->stats.tx_errors++;
 898
 899                 switch (urb->status) {
 900                 case -EPIPE:
 901                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
 902                         break;
 903
 904                 /* software-driven interface shutdown */
 905                 case -ECONNRESET:               // async unlink
 906                 case -ESHUTDOWN:                // hardware gone
 907                         break;
 908
 909                 // like rx, tx gets controller i/o faults during khubd delays
 910                 // and so it uses the same throttling mechanism.
 911                 case -EPROTO:
 912                 case -ETIME:
 913                 case -EILSEQ:
 914                         if (!timer_pending (&dev->delay)) {
 915                                 mod_timer (&dev->delay,
 916                                         jiffies + THROTTLE_JIFFIES);
 917                                 if (netif_msg_link (dev))
 918                                         devdbg (dev, "tx throttle %d",
 919                                                         urb->status);
 920                         }
 921                         netif_stop_queue (dev->net);
 922                         break;
 923                 default:
 924                         if (netif_msg_tx_err (dev))
 925                                 devdbg (dev, "tx err %d", entry->urb->status);
 926                         break;
 927                 }
 928         }
 929
 930         urb->dev = NULL;
 931         entry->state = tx_done;
 932         defer_bh(dev, skb, &dev->txq);
 933 }
 934
 935 /*-------------------------------------------------------------------------*/
 936
 937 void usbnet_tx_timeout (struct net_device *net)
 938 {
 939         struct usbnet           *dev = netdev_priv(net);
 940
 941         unlink_urbs (dev, &dev->txq);
 942         tasklet_schedule (&dev->bh);
 943
 944         // FIXME: device recovery -- reset?
 945 }
 946 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
 947
 948 /*-------------------------------------------------------------------------*/
 949
 950 int usbnet_start_xmit (struct sk_buff *skb, struct net_device *net)
 951 {
 952         struct usbnet           *dev = netdev_priv(net);
 953         int                     length;
 954         int                     retval = NET_XMIT_SUCCESS;
 955         struct urb              *urb = NULL;
 956         struct skb_data         *entry;
 957         struct driver_info      *info = dev->driver_info;
 958         unsigned long           flags;
 959
 960         // some devices want funky USB-level framing, for
 961         // win32 driver (usually) and/or hardware quirks
 962         if (info->tx_fixup) {
 963                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
 964                 if (!skb) {
 965                         if (netif_msg_tx_err (dev))
 966                                 devdbg (dev, "can't tx_fixup skb");
 967                         goto drop;
 968                 }
 969         }
 970         length = skb->len;
 971
 972         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
 973                 if (netif_msg_tx_err (dev))
 974                         devdbg (dev, "no urb");
 975                 goto drop;
 976         }
 977
 978         entry = (struct skb_data *) skb->cb;
 979         entry->urb = urb;
 980         entry->dev = dev;
 981         entry->state = tx_start;
 982         entry->length = length;
 983
 984         usb_fill_bulk_urb (urb, dev->udev, dev->out,
 985                         skb->data, skb->len, tx_complete, skb);
 986
 987         /* don't assume the hardware handles USB_ZERO_PACKET
 988          * NOTE:  strictly conforming cdc-ether devices should expect
 989          * the ZLP here, but ignore the one-byte packet.
 990          */
 991         if ((length % dev->maxpacket) == 0) {
 992                 urb->transfer_buffer_length++;
 993                 if (skb_tailroom(skb)) {
 994                         skb->data[skb->len] = 0;
 995                         __skb_put(skb, 1);
 996                 }
 997         }
 998
 999         spin_lock_irqsave (&dev->txq.lock, flags);
1000
1001         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1002         case -EPIPE:
1003                 netif_stop_queue (net);
1004                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1005                 break;
1006         default:
1007                 if (netif_msg_tx_err (dev))
1008                         devdbg (dev, "tx: submit urb err %d", retval);
1009                 break;
1010         case 0:
1011                 net->trans_start = jiffies;
1012                 __skb_queue_tail (&dev->txq, skb);
1013                 if (dev->txq.qlen >= TX_QLEN (dev))
1014                         netif_stop_queue (net);
1015         }
1016         spin_unlock_irqrestore (&dev->txq.lock, flags);
1017
1018         if (retval) {
1019                 if (netif_msg_tx_err (dev))
1020                         devdbg (dev, "drop, code %d", retval);
1021 drop:
1022                 retval = NET_XMIT_SUCCESS;
1023                 dev->net->stats.tx_dropped++;
1024                 if (skb)
1025                         dev_kfree_skb_any (skb);
1026                 usb_free_urb (urb);
1027         } else if (netif_msg_tx_queued (dev)) {
1028                 devdbg (dev, "> tx, len %d, type 0x%x",
1029                         length, skb->protocol);
1030         }
1031         return retval;
1032 }
1033 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1034
1035 /*-------------------------------------------------------------------------*/
1036
1037 // tasklet (work deferred from completions, in_irq) or timer
1038
1039 static void usbnet_bh (unsigned long param)
1040 {
1041         struct usbnet           *dev = (struct usbnet *) param;
1042         struct sk_buff          *skb;
1043         struct skb_data         *entry;
1044
1045         while ((skb = skb_dequeue (&dev->done))) {
1046                 entry = (struct skb_data *) skb->cb;
1047                 switch (entry->state) {
1048                 case rx_done:
1049                         entry->state = rx_cleanup;
1050                         rx_process (dev, skb);
1051                         continue;
1052                 case tx_done:
1053                 case rx_cleanup:
1054                         usb_free_urb (entry->urb);
1055                         dev_kfree_skb (skb);
1056                         continue;
1057                 default:
1058                         devdbg (dev, "bogus skb state %d", entry->state);
1059                 }
1060         }
1061
1062         // waiting for all pending urbs to complete?
1063         if (dev->wait) {
1064                 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1065                         wake_up (dev->wait);
1066                 }
1067
1068         // or are we maybe short a few urbs?
1069         } else if (netif_running (dev->net)
1070                         && netif_device_present (dev->net)
1071                         && !timer_pending (&dev->delay)
1072                         && !test_bit (EVENT_RX_HALT, &dev->flags)) {
1073                 int     temp = dev->rxq.qlen;
1074                 int     qlen = RX_QLEN (dev);
1075
1076                 if (temp < qlen) {
1077                         struct urb      *urb;
1078                         int             i;
1079
1080                         // don't refill the queue all at once
1081                         for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1082                                 urb = usb_alloc_urb (0, GFP_ATOMIC);
1083                                 if (urb != NULL)
1084                                         rx_submit (dev, urb, GFP_ATOMIC);
1085                         }
1086                         if (temp != dev->rxq.qlen && netif_msg_link (dev))
1087                                 devdbg (dev, "rxqlen %d --> %d",
1088                                                 temp, dev->rxq.qlen);
1089                         if (dev->rxq.qlen < qlen)
1090                                 tasklet_schedule (&dev->bh);
1091                 }
1092                 if (dev->txq.qlen < TX_QLEN (dev))
1093                         netif_wake_queue (dev->net);
1094         }
1095 }
1096
1097
1098 \f
1099 /*-------------------------------------------------------------------------
1100  *
1101  * USB Device Driver support
1102  *
1103  *-------------------------------------------------------------------------*/
1104
1105 // precondition: never called in_interrupt
1106
1107 void usbnet_disconnect (struct usb_interface *intf)
1108 {
1109         struct usbnet           *dev;
1110         struct usb_device       *xdev;
1111         struct net_device       *net;
1112
1113         dev = usb_get_intfdata(intf);
1114         usb_set_intfdata(intf, NULL);
1115         if (!dev)
1116                 return;
1117
1118         xdev = interface_to_usbdev (intf);
1119
1120         if (netif_msg_probe (dev))
1121                 devinfo (dev, "unregister '%s' usb-%s-%s, %s",
1122                         intf->dev.driver->name,
1123                         xdev->bus->bus_name, xdev->devpath,
1124                         dev->driver_info->description);
1125
1126         net = dev->net;
1127         unregister_netdev (net);
1128
1129         /* we don't hold rtnl here ... */
1130         flush_scheduled_work ();
1131
1132         if (dev->driver_info->unbind)
1133                 dev->driver_info->unbind (dev, intf);
1134
1135         free_netdev(net);
1136         usb_put_dev (xdev);
1137 }
1138 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1139
1140 static const struct net_device_ops usbnet_netdev_ops = {
1141         .ndo_open               = usbnet_open,
1142         .ndo_stop               = usbnet_stop,
1143         .ndo_start_xmit         = usbnet_start_xmit,
1144         .ndo_tx_timeout         = usbnet_tx_timeout,
1145         .ndo_change_mtu         = usbnet_change_mtu,
1146         .ndo_set_mac_address    = eth_mac_addr,
1147         .ndo_validate_addr      = eth_validate_addr,
1148 };
1149
1150 /*-------------------------------------------------------------------------*/
1151
1152 // precondition: never called in_interrupt
1153
1154 int
1155 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1156 {
1157         struct usbnet                   *dev;
1158         struct net_device               *net;
1159         struct usb_host_interface       *interface;
1160         struct driver_info              *info;
1161         struct usb_device               *xdev;
1162         int                             status;
1163         const char                      *name;
1164
1165         name = udev->dev.driver->name;
1166         info = (struct driver_info *) prod->driver_info;
1167         if (!info) {
1168                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1169                 return -ENODEV;
1170         }
1171         xdev = interface_to_usbdev (udev);
1172         interface = udev->cur_altsetting;
1173
1174         usb_get_dev (xdev);
1175
1176         status = -ENOMEM;
1177
1178         // set up our own records
1179         net = alloc_etherdev(sizeof(*dev));
1180         if (!net) {
1181                 dbg ("can't kmalloc dev");
1182                 goto out;
1183         }
1184
1185         dev = netdev_priv(net);
1186         dev->udev = xdev;
1187         dev->intf = udev;
1188         dev->driver_info = info;
1189         dev->driver_name = name;
1190         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1191                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1192         skb_queue_head_init (&dev->rxq);
1193         skb_queue_head_init (&dev->txq);
1194         skb_queue_head_init (&dev->done);
1195         dev->bh.func = usbnet_bh;
1196         dev->bh.data = (unsigned long) dev;
1197         INIT_WORK (&dev->kevent, kevent);
1198         dev->delay.function = usbnet_bh;
1199         dev->delay.data = (unsigned long) dev;
1200         init_timer (&dev->delay);
1201         mutex_init (&dev->phy_mutex);
1202
1203         dev->net = net;
1204         strcpy (net->name, "usb%d");
1205         memcpy (net->dev_addr, node_id, sizeof node_id);
1206
1207         /* rx and tx sides can use different message sizes;
1208          * bind() should set rx_urb_size in that case.
1209          */
1210         dev->hard_mtu = net->mtu + net->hard_header_len;
1211 #if 0
1212 // dma_supported() is deeply broken on almost all architectures
1213         // possible with some EHCI controllers
1214         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1215                 net->features |= NETIF_F_HIGHDMA;
1216 #endif
1217
1218         net->netdev_ops = &usbnet_netdev_ops;
1219         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1220         net->ethtool_ops = &usbnet_ethtool_ops;
1221
1222         // allow device-specific bind/init procedures
1223         // NOTE net->name still not usable ...
1224         if (info->bind) {
1225                 status = info->bind (dev, udev);
1226                 if (status < 0)
1227                         goto out1;
1228
1229                 // heuristic:  "usb%d" for links we know are two-host,
1230                 // else "eth%d" when there's reasonable doubt.  userspace
1231                 // can rename the link if it knows better.
1232                 if ((dev->driver_info->flags & FLAG_ETHER) != 0
1233                                 && (net->dev_addr [0] & 0x02) == 0)
1234                         strcpy (net->name, "eth%d");
1235                 /* WLAN devices should always be named "wlan%d" */
1236                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1237                         strcpy(net->name, "wlan%d");
1238
1239                 /* maybe the remote can't receive an Ethernet MTU */
1240                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1241                         net->mtu = dev->hard_mtu - net->hard_header_len;
1242         } else if (!info->in || !info->out)
1243                 status = usbnet_get_endpoints (dev, udev);
1244         else {
1245                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1246                 dev->out = usb_sndbulkpipe (xdev, info->out);
1247                 if (!(info->flags & FLAG_NO_SETINT))
1248                         status = usb_set_interface (xdev,
1249                                 interface->desc.bInterfaceNumber,
1250                                 interface->desc.bAlternateSetting);
1251                 else
1252                         status = 0;
1253
1254         }
1255         if (status >= 0 && dev->status)
1256                 status = init_status (dev, udev);
1257         if (status < 0)
1258                 goto out3;
1259
1260         if (!dev->rx_urb_size)
1261                 dev->rx_urb_size = dev->hard_mtu;
1262         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1263
1264         SET_NETDEV_DEV(net, &udev->dev);
1265         status = register_netdev (net);
1266         if (status)
1267                 goto out3;
1268         if (netif_msg_probe (dev))
1269                 devinfo (dev, "register '%s' at usb-%s-%s, %s, %pM",
1270                         udev->dev.driver->name,
1271                         xdev->bus->bus_name, xdev->devpath,
1272                         dev->driver_info->description,
1273                         net->dev_addr);
1274
1275         // ok, it's ready to go.
1276         usb_set_intfdata (udev, dev);
1277
1278         // start as if the link is up
1279         netif_device_attach (net);
1280
1281         return 0;
1282
1283 out3:
1284         if (info->unbind)
1285                 info->unbind (dev, udev);
1286 out1:
1287         free_netdev(net);
1288 out:
1289         usb_put_dev(xdev);
1290         return status;
1291 }
1292 EXPORT_SYMBOL_GPL(usbnet_probe);
1293
1294 /*-------------------------------------------------------------------------*/
1295
1296 /*
1297  * suspend the whole driver as soon as the first interface is suspended
1298  * resume only when the last interface is resumed
1299  */
1300
1301 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1302 {
1303         struct usbnet           *dev = usb_get_intfdata(intf);
1304
1305         if (!dev->suspend_count++) {
1306                 /*
1307                  * accelerate emptying of the rx and queues, to avoid
1308                  * having everything error out.
1309                  */
1310                 netif_device_detach (dev->net);
1311                 (void) unlink_urbs (dev, &dev->rxq);
1312                 (void) unlink_urbs (dev, &dev->txq);
1313                 /*
1314                  * reattach so runtime management can use and
1315                  * wake the device
1316                  */
1317                 netif_device_attach (dev->net);
1318         }
1319         return 0;
1320 }
1321 EXPORT_SYMBOL_GPL(usbnet_suspend);
1322
1323 int usbnet_resume (struct usb_interface *intf)
1324 {
1325         struct usbnet           *dev = usb_get_intfdata(intf);
1326
1327         if (!--dev->suspend_count)
1328                 tasklet_schedule (&dev->bh);
1329
1330         return 0;
1331 }
1332 EXPORT_SYMBOL_GPL(usbnet_resume);
1333
1334
1335 /*-------------------------------------------------------------------------*/
1336
1337 static int __init usbnet_init(void)
1338 {
1339         /* compiler should optimize this out */
1340         BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1341                         < sizeof (struct skb_data));
1342
1343         random_ether_addr(node_id);
1344         return 0;
1345 }
1346 module_init(usbnet_init);
1347
1348 static void __exit usbnet_exit(void)
1349 {
1350 }
1351 module_exit(usbnet_exit);
1352
1353 MODULE_AUTHOR("David Brownell");
1354 MODULE_DESCRIPTION("USB network driver framework");
1355 MODULE_LICENSE("GPL");