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         if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 237                 skb_queue_tail(&dev->rxq_pause, skb);
 238                 return;
 239         }
 240
 241         skb->protocol = eth_type_trans (skb, dev->net);
 242         dev->net->stats.rx_packets++;
 243         dev->net->stats.rx_bytes += skb->len;
 244
 245         if (netif_msg_rx_status (dev))
 246                 devdbg (dev, "< rx, len %zu, type 0x%x",
 247                         skb->len + sizeof (struct ethhdr), skb->protocol);
 248         memset (skb->cb, 0, sizeof (struct skb_data));
 249         status = netif_rx (skb);
 250         if (status != NET_RX_SUCCESS && netif_msg_rx_err (dev))
 251                 devdbg (dev, "netif_rx status %d", status);
 252 }
 253 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 254
 255 \f
 256 /*-------------------------------------------------------------------------
 257  *
 258  * Network Device Driver (peer link to "Host Device", from USB host)
 259  *
 260  *-------------------------------------------------------------------------*/
 261
 262 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 263 {
 264         struct usbnet   *dev = netdev_priv(net);
 265         int             ll_mtu = new_mtu + net->hard_header_len;
 266         int             old_hard_mtu = dev->hard_mtu;
 267         int             old_rx_urb_size = dev->rx_urb_size;
 268
 269         if (new_mtu <= 0)
 270                 return -EINVAL;
 271         // no second zero-length packet read wanted after mtu-sized packets
 272         if ((ll_mtu % dev->maxpacket) == 0)
 273                 return -EDOM;
 274         net->mtu = new_mtu;
 275
 276         dev->hard_mtu = net->mtu + net->hard_header_len;
 277         if (dev->rx_urb_size == old_hard_mtu) {
 278                 dev->rx_urb_size = dev->hard_mtu;
 279                 if (dev->rx_urb_size > old_rx_urb_size)
 280                         usbnet_unlink_rx_urbs(dev);
 281         }
 282
 283         return 0;
 284 }
 285 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 286
 287 /*-------------------------------------------------------------------------*/
 288
 289 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 290  * completion callbacks.  2.5 should have fixed those bugs...
 291  */
 292
 293 static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 294 {
 295         unsigned long           flags;
 296
 297         spin_lock_irqsave(&list->lock, flags);
 298         __skb_unlink(skb, list);
 299         spin_unlock(&list->lock);
 300         spin_lock(&dev->done.lock);
 301         __skb_queue_tail(&dev->done, skb);
 302         if (dev->done.qlen == 1)
 303                 tasklet_schedule(&dev->bh);
 304         spin_unlock_irqrestore(&dev->done.lock, flags);
 305 }
 306
 307 /* some work can't be done in tasklets, so we use keventd
 308  *
 309  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 310  * but tasklet_schedule() doesn't.  hope the failure is rare.
 311  */
 312 void usbnet_defer_kevent (struct usbnet *dev, int work)
 313 {
 314         set_bit (work, &dev->flags);
 315         if (!schedule_work (&dev->kevent))
 316                 deverr (dev, "kevent %d may have been dropped", work);
 317         else
 318                 devdbg (dev, "kevent %d scheduled", work);
 319 }
 320 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 321
 322 /*-------------------------------------------------------------------------*/
 323
 324 static void rx_complete (struct urb *urb);
 325
 326 static void rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 327 {
 328         struct sk_buff          *skb;
 329         struct skb_data         *entry;
 330         int                     retval = 0;
 331         unsigned long           lockflags;
 332         size_t                  size = dev->rx_urb_size;
 333
 334         if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
 335                 if (netif_msg_rx_err (dev))
 336                         devdbg (dev, "no rx skb");
 337                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 338                 usb_free_urb (urb);
 339                 return;
 340         }
 341         skb_reserve (skb, NET_IP_ALIGN);
 342
 343         entry = (struct skb_data *) skb->cb;
 344         entry->urb = urb;
 345         entry->dev = dev;
 346         entry->state = rx_start;
 347         entry->length = 0;
 348
 349         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 350                 skb->data, size, rx_complete, skb);
 351
 352         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 353
 354         if (netif_running (dev->net)
 355                         && netif_device_present (dev->net)
 356                         && !test_bit (EVENT_RX_HALT, &dev->flags)) {
 357                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 358                 case -EPIPE:
 359                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 360                         break;
 361                 case -ENOMEM:
 362                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 363                         break;
 364                 case -ENODEV:
 365                         if (netif_msg_ifdown (dev))
 366                                 devdbg (dev, "device gone");
 367                         netif_device_detach (dev->net);
 368                         break;
 369                 default:
 370                         if (netif_msg_rx_err (dev))
 371                                 devdbg (dev, "rx submit, %d", retval);
 372                         tasklet_schedule (&dev->bh);
 373                         break;
 374                 case 0:
 375                         __skb_queue_tail (&dev->rxq, skb);
 376                 }
 377         } else {
 378                 if (netif_msg_ifdown (dev))
 379                         devdbg (dev, "rx: stopped");
 380                 retval = -ENOLINK;
 381         }
 382         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 383         if (retval) {
 384                 dev_kfree_skb_any (skb);
 385                 usb_free_urb (urb);
 386         }
 387 }
 388
 389
 390 /*-------------------------------------------------------------------------*/
 391
 392 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 393 {
 394         if (dev->driver_info->rx_fixup
 395                         && !dev->driver_info->rx_fixup (dev, skb))
 396                 goto error;
 397         // else network stack removes extra byte if we forced a short packet
 398
 399         if (skb->len)
 400                 usbnet_skb_return (dev, skb);
 401         else {
 402                 if (netif_msg_rx_err (dev))
 403                         devdbg (dev, "drop");
 404 error:
 405                 dev->net->stats.rx_errors++;
 406                 skb_queue_tail (&dev->done, skb);
 407         }
 408 }
 409
 410 /*-------------------------------------------------------------------------*/
 411
 412 static void rx_complete (struct urb *urb)
 413 {
 414         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 415         struct skb_data         *entry = (struct skb_data *) skb->cb;
 416         struct usbnet           *dev = entry->dev;
 417         int                     urb_status = urb->status;
 418
 419         skb_put (skb, urb->actual_length);
 420         entry->state = rx_done;
 421         entry->urb = NULL;
 422
 423         switch (urb_status) {
 424         /* success */
 425         case 0:
 426                 if (skb->len < dev->net->hard_header_len) {
 427                         entry->state = rx_cleanup;
 428                         dev->net->stats.rx_errors++;
 429                         dev->net->stats.rx_length_errors++;
 430                         if (netif_msg_rx_err (dev))
 431                                 devdbg (dev, "rx length %d", skb->len);
 432                 }
 433                 break;
 434
 435         /* stalls need manual reset. this is rare ... except that
 436          * when going through USB 2.0 TTs, unplug appears this way.
 437          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 438          * storm, recovering as needed.
 439          */
 440         case -EPIPE:
 441                 dev->net->stats.rx_errors++;
 442                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 443                 // FALLTHROUGH
 444
 445         /* software-driven interface shutdown */
 446         case -ECONNRESET:               /* async unlink */
 447         case -ESHUTDOWN:                /* hardware gone */
 448                 if (netif_msg_ifdown (dev))
 449                         devdbg (dev, "rx shutdown, code %d", urb_status);
 450                 goto block;
 451
 452         /* we get controller i/o faults during khubd disconnect() delays.
 453          * throttle down resubmits, to avoid log floods; just temporarily,
 454          * so we still recover when the fault isn't a khubd delay.
 455          */
 456         case -EPROTO:
 457         case -ETIME:
 458         case -EILSEQ:
 459                 dev->net->stats.rx_errors++;
 460                 if (!timer_pending (&dev->delay)) {
 461                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 462                         if (netif_msg_link (dev))
 463                                 devdbg (dev, "rx throttle %d", urb_status);
 464                 }
 465 block:
 466                 entry->state = rx_cleanup;
 467                 entry->urb = urb;
 468                 urb = NULL;
 469                 break;
 470
 471         /* data overrun ... flush fifo? */
 472         case -EOVERFLOW:
 473                 dev->net->stats.rx_over_errors++;
 474                 // FALLTHROUGH
 475
 476         default:
 477                 entry->state = rx_cleanup;
 478                 dev->net->stats.rx_errors++;
 479                 if (netif_msg_rx_err (dev))
 480                         devdbg (dev, "rx status %d", urb_status);
 481                 break;
 482         }
 483
 484         defer_bh(dev, skb, &dev->rxq);
 485
 486         if (urb) {
 487                 if (netif_running (dev->net)
 488                                 && !test_bit (EVENT_RX_HALT, &dev->flags)) {
 489                         rx_submit (dev, urb, GFP_ATOMIC);
 490                         return;
 491                 }
 492                 usb_free_urb (urb);
 493         }
 494         if (netif_msg_rx_err (dev))
 495                 devdbg (dev, "no read resubmitted");
 496 }
 497
 498 static void intr_complete (struct urb *urb)
 499 {
 500         struct usbnet   *dev = urb->context;
 501         int             status = urb->status;
 502
 503         switch (status) {
 504         /* success */
 505         case 0:
 506                 dev->driver_info->status(dev, urb);
 507                 break;
 508
 509         /* software-driven interface shutdown */
 510         case -ENOENT:           /* urb killed */
 511         case -ESHUTDOWN:        /* hardware gone */
 512                 if (netif_msg_ifdown (dev))
 513                         devdbg (dev, "intr shutdown, code %d", status);
 514                 return;
 515
 516         /* NOTE:  not throttling like RX/TX, since this endpoint
 517          * already polls infrequently
 518          */
 519         default:
 520                 devdbg (dev, "intr status %d", status);
 521                 break;
 522         }
 523
 524         if (!netif_running (dev->net))
 525                 return;
 526
 527         memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 528         status = usb_submit_urb (urb, GFP_ATOMIC);
 529         if (status != 0 && netif_msg_timer (dev))
 530                 deverr(dev, "intr resubmit --> %d", status);
 531 }
 532
 533 /*-------------------------------------------------------------------------*/
 534 void usbnet_pause_rx(struct usbnet *dev)
 535 {
 536         set_bit(EVENT_RX_PAUSED, &dev->flags);
 537
 538         if (netif_msg_rx_status(dev))
 539                 devdbg(dev, "paused rx queue enabled");
 540 }
 541 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 542
 543 void usbnet_resume_rx(struct usbnet *dev)
 544 {
 545         struct sk_buff *skb;
 546         int num = 0;
 547
 548         clear_bit(EVENT_RX_PAUSED, &dev->flags);
 549
 550         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 551                 usbnet_skb_return(dev, skb);
 552                 num++;
 553         }
 554
 555         tasklet_schedule(&dev->bh);
 556
 557         if (netif_msg_rx_status(dev))
 558                 devdbg(dev, "paused rx queue disabled, %d skbs requeued", num);
 559 }
 560 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 561
 562 void usbnet_purge_paused_rxq(struct usbnet *dev)
 563 {
 564         skb_queue_purge(&dev->rxq_pause);
 565 }
 566 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 567
 568 /*-------------------------------------------------------------------------*/
 569
 570 // unlink pending rx/tx; completion handlers do all other cleanup
 571
 572 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 573 {
 574         unsigned long           flags;
 575         struct sk_buff          *skb, *skbnext;
 576         int                     count = 0;
 577
 578         spin_lock_irqsave (&q->lock, flags);
 579         skb_queue_walk_safe(q, skb, skbnext) {
 580                 struct skb_data         *entry;
 581                 struct urb              *urb;
 582                 int                     retval;
 583
 584                 entry = (struct skb_data *) skb->cb;
 585                 urb = entry->urb;
 586
 587                 // during some PM-driven resume scenarios,
 588                 // these (async) unlinks complete immediately
 589                 retval = usb_unlink_urb (urb);
 590                 if (retval != -EINPROGRESS && retval != 0)
 591                         devdbg (dev, "unlink urb err, %d", retval);
 592                 else
 593                         count++;
 594         }
 595         spin_unlock_irqrestore (&q->lock, flags);
 596         return count;
 597 }
 598
 599 // Flush all pending rx urbs
 600 // minidrivers may need to do this when the MTU changes
 601
 602 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 603 {
 604         if (netif_running(dev->net)) {
 605                 (void) unlink_urbs (dev, &dev->rxq);
 606                 tasklet_schedule(&dev->bh);
 607         }
 608 }
 609 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 610
 611 /*-------------------------------------------------------------------------*/
 612
 613 // precondition: never called in_interrupt
 614
 615 int usbnet_stop (struct net_device *net)
 616 {
 617         struct usbnet           *dev = netdev_priv(net);
 618         struct driver_info      *info = dev->driver_info;
 619         int                     temp;
 620         int                     retval;
 621         DECLARE_WAIT_QUEUE_HEAD_ONSTACK (unlink_wakeup);
 622         DECLARE_WAITQUEUE (wait, current);
 623
 624         netif_stop_queue (net);
 625
 626         if (netif_msg_ifdown (dev))
 627                 devinfo (dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld",
 628                         net->stats.rx_packets, net->stats.tx_packets,
 629                         net->stats.rx_errors, net->stats.tx_errors
 630                         );
 631
 632         /* allow minidriver to stop correctly (wireless devices to turn off
 633          * radio etc) */
 634         if (info->stop) {
 635                 retval = info->stop(dev);
 636                 if (retval < 0 && netif_msg_ifdown(dev))
 637                         devinfo(dev,
 638                                 "stop fail (%d) usbnet usb-%s-%s, %s",
 639                                 retval,
 640                                 dev->udev->bus->bus_name, dev->udev->devpath,
 641                                 info->description);
 642         }
 643
 644         if (!(info->flags & FLAG_AVOID_UNLINK_URBS)) {
 645                 /* ensure there are no more active urbs */
 646                 add_wait_queue(&unlink_wakeup, &wait);
 647                 dev->wait = &unlink_wakeup;
 648                 temp = unlink_urbs(dev, &dev->txq) +
 649                         unlink_urbs(dev, &dev->rxq);
 650
 651                 /* maybe wait for deletions to finish. */
 652                 while (!skb_queue_empty(&dev->rxq)
 653                                 && !skb_queue_empty(&dev->txq)
 654                                 && !skb_queue_empty(&dev->done)) {
 655                         msleep(UNLINK_TIMEOUT_MS);
 656                         if (netif_msg_ifdown(dev))
 657                                 devdbg(dev, "waited for %d urb completions",
 658                                         temp);
 659                 }
 660                 dev->wait = NULL;
 661                 remove_wait_queue(&unlink_wakeup, &wait);
 662         }
 663
 664         usb_kill_urb(dev->interrupt);
 665
 666         usbnet_purge_paused_rxq(dev);
 667
 668         /* deferred work (task, timer, softirq) must also stop.
 669          * can't flush_scheduled_work() until we drop rtnl (later),
 670          * else workers could deadlock; so make workers a NOP.
 671          */
 672         dev->flags = 0;
 673         del_timer_sync (&dev->delay);
 674         tasklet_kill (&dev->bh);
 675         usb_autopm_put_interface(dev->intf);
 676
 677         return 0;
 678 }
 679 EXPORT_SYMBOL_GPL(usbnet_stop);
 680
 681 /*-------------------------------------------------------------------------*/
 682
 683 // posts reads, and enables write queuing
 684
 685 // precondition: never called in_interrupt
 686
 687 int usbnet_open (struct net_device *net)
 688 {
 689         struct usbnet           *dev = netdev_priv(net);
 690         int                     retval;
 691         struct driver_info      *info = dev->driver_info;
 692
 693         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 694                 if (netif_msg_ifup (dev))
 695                         devinfo (dev,
 696                                 "resumption fail (%d) usbnet usb-%s-%s, %s",
 697                                 retval,
 698                                 dev->udev->bus->bus_name, dev->udev->devpath,
 699                         info->description);
 700                 goto done_nopm;
 701         }
 702
 703         // put into "known safe" state
 704         if (info->reset && (retval = info->reset (dev)) < 0) {
 705                 if (netif_msg_ifup (dev))
 706                         devinfo (dev,
 707                                 "open reset fail (%d) usbnet usb-%s-%s, %s",
 708                                 retval,
 709                                 dev->udev->bus->bus_name, dev->udev->devpath,
 710                         info->description);
 711                 goto done;
 712         }
 713
 714         // insist peer be connected
 715         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 716                 if (netif_msg_ifup (dev))
 717                         devdbg (dev, "can't open; %d", retval);
 718                 goto done;
 719         }
 720
 721         /* start any status interrupt transfer */
 722         if (dev->interrupt) {
 723                 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 724                 if (retval < 0) {
 725                         if (netif_msg_ifup (dev))
 726                                 deverr (dev, "intr submit %d", retval);
 727                         goto done;
 728                 }
 729         }
 730
 731         netif_start_queue (net);
 732         if (netif_msg_ifup (dev)) {
 733                 char    *framing;
 734
 735                 if (dev->driver_info->flags & FLAG_FRAMING_NC)
 736                         framing = "NetChip";
 737                 else if (dev->driver_info->flags & FLAG_FRAMING_GL)
 738                         framing = "GeneSys";
 739                 else if (dev->driver_info->flags & FLAG_FRAMING_Z)
 740                         framing = "Zaurus";
 741                 else if (dev->driver_info->flags & FLAG_FRAMING_RN)
 742                         framing = "RNDIS";
 743                 else if (dev->driver_info->flags & FLAG_FRAMING_AX)
 744                         framing = "ASIX";
 745                 else
 746                         framing = "simple";
 747
 748                 devinfo (dev, "open: enable queueing "
 749                                 "(rx %d, tx %d) mtu %d %s framing",
 750                         (int)RX_QLEN (dev), (int)TX_QLEN (dev), dev->net->mtu,
 751                         framing);
 752         }
 753
 754         // delay posting reads until we're fully open
 755         tasklet_schedule (&dev->bh);
 756         return retval;
 757 done:
 758         usb_autopm_put_interface(dev->intf);
 759 done_nopm:
 760         return retval;
 761 }
 762 EXPORT_SYMBOL_GPL(usbnet_open);
 763
 764 /*-------------------------------------------------------------------------*/
 765
 766 /* ethtool methods; minidrivers may need to add some more, but
 767  * they'll probably want to use this base set.
 768  */
 769
 770 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 771 {
 772         struct usbnet *dev = netdev_priv(net);
 773
 774         if (!dev->mii.mdio_read)
 775                 return -EOPNOTSUPP;
 776
 777         return mii_ethtool_gset(&dev->mii, cmd);
 778 }
 779 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 780
 781 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 782 {
 783         struct usbnet *dev = netdev_priv(net);
 784         int retval;
 785
 786         if (!dev->mii.mdio_write)
 787                 return -EOPNOTSUPP;
 788
 789         retval = mii_ethtool_sset(&dev->mii, cmd);
 790
 791         /* link speed/duplex might have changed */
 792         if (dev->driver_info->link_reset)
 793                 dev->driver_info->link_reset(dev);
 794
 795         return retval;
 796
 797 }
 798 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 799
 800 u32 usbnet_get_link (struct net_device *net)
 801 {
 802         struct usbnet *dev = netdev_priv(net);
 803
 804         /* If a check_connect is defined, return its result */
 805         if (dev->driver_info->check_connect)
 806                 return dev->driver_info->check_connect (dev) == 0;
 807
 808         /* if the device has mii operations, use those */
 809         if (dev->mii.mdio_read)
 810                 return mii_link_ok(&dev->mii);
 811
 812         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 813         return ethtool_op_get_link(net);
 814 }
 815 EXPORT_SYMBOL_GPL(usbnet_get_link);
 816
 817 int usbnet_nway_reset(struct net_device *net)
 818 {
 819         struct usbnet *dev = netdev_priv(net);
 820
 821         if (!dev->mii.mdio_write)
 822                 return -EOPNOTSUPP;
 823
 824         return mii_nway_restart(&dev->mii);
 825 }
 826 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 827
 828 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 829 {
 830         struct usbnet *dev = netdev_priv(net);
 831
 832         strncpy (info->driver, dev->driver_name, sizeof info->driver);
 833         strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 834         strncpy (info->fw_version, dev->driver_info->description,
 835                 sizeof info->fw_version);
 836         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 837 }
 838 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 839
 840 u32 usbnet_get_msglevel (struct net_device *net)
 841 {
 842         struct usbnet *dev = netdev_priv(net);
 843
 844         return dev->msg_enable;
 845 }
 846 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 847
 848 void usbnet_set_msglevel (struct net_device *net, u32 level)
 849 {
 850         struct usbnet *dev = netdev_priv(net);
 851
 852         dev->msg_enable = level;
 853 }
 854 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 855
 856 /* drivers may override default ethtool_ops in their bind() routine */
 857 static const struct ethtool_ops usbnet_ethtool_ops = {
 858         .get_settings           = usbnet_get_settings,
 859         .set_settings           = usbnet_set_settings,
 860         .get_link               = usbnet_get_link,
 861         .nway_reset             = usbnet_nway_reset,
 862         .get_drvinfo            = usbnet_get_drvinfo,
 863         .get_msglevel           = usbnet_get_msglevel,
 864         .set_msglevel           = usbnet_set_msglevel,
 865 };
 866
 867 /*-------------------------------------------------------------------------*/
 868
 869 /* work that cannot be done in interrupt context uses keventd.
 870  *
 871  * NOTE:  with 2.5 we could do more of this using completion callbacks,
 872  * especially now that control transfers can be queued.
 873  */
 874 static void
 875 kevent (struct work_struct *work)
 876 {
 877         struct usbnet           *dev =
 878                 container_of(work, struct usbnet, kevent);
 879         int                     status;
 880
 881         /* usb_clear_halt() needs a thread context */
 882         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 883                 unlink_urbs (dev, &dev->txq);
 884                 status = usb_clear_halt (dev->udev, dev->out);
 885                 if (status < 0
 886                                 && status != -EPIPE
 887                                 && status != -ESHUTDOWN) {
 888                         if (netif_msg_tx_err (dev))
 889                                 deverr (dev, "can't clear tx halt, status %d",
 890                                         status);
 891                 } else {
 892                         clear_bit (EVENT_TX_HALT, &dev->flags);
 893                         if (status != -ESHUTDOWN)
 894                                 netif_wake_queue (dev->net);
 895                 }
 896         }
 897         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 898                 unlink_urbs (dev, &dev->rxq);
 899                 status = usb_clear_halt (dev->udev, dev->in);
 900                 if (status < 0
 901                                 && status != -EPIPE
 902                                 && status != -ESHUTDOWN) {
 903                         if (netif_msg_rx_err (dev))
 904                                 deverr (dev, "can't clear rx halt, status %d",
 905                                         status);
 906                 } else {
 907                         clear_bit (EVENT_RX_HALT, &dev->flags);
 908                         tasklet_schedule (&dev->bh);
 909                 }
 910         }
 911
 912         /* tasklet could resubmit itself forever if memory is tight */
 913         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 914                 struct urb      *urb = NULL;
 915
 916                 if (netif_running (dev->net))
 917                         urb = usb_alloc_urb (0, GFP_KERNEL);
 918                 else
 919                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 920                 if (urb != NULL) {
 921                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 922                         rx_submit (dev, urb, GFP_KERNEL);
 923                         tasklet_schedule (&dev->bh);
 924                 }
 925         }
 926
 927         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 928                 struct driver_info      *info = dev->driver_info;
 929                 int                     retval = 0;
 930
 931                 clear_bit (EVENT_LINK_RESET, &dev->flags);
 932                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 933                         devinfo(dev, "link reset failed (%d) usbnet usb-%s-%s, %s",
 934                                 retval,
 935                                 dev->udev->bus->bus_name, dev->udev->devpath,
 936                                 info->description);
 937                 }
 938         }
 939
 940         if (dev->flags)
 941                 devdbg (dev, "kevent done, flags = 0x%lx",
 942                         dev->flags);
 943 }
 944
 945 /*-------------------------------------------------------------------------*/
 946
 947 static void tx_complete (struct urb *urb)
 948 {
 949         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 950         struct skb_data         *entry = (struct skb_data *) skb->cb;
 951         struct usbnet           *dev = entry->dev;
 952
 953         if (urb->status == 0) {
 954                 dev->net->stats.tx_packets++;
 955                 dev->net->stats.tx_bytes += entry->length;
 956         } else {
 957                 dev->net->stats.tx_errors++;
 958
 959                 switch (urb->status) {
 960                 case -EPIPE:
 961                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
 962                         break;
 963
 964                 /* software-driven interface shutdown */
 965                 case -ECONNRESET:               // async unlink
 966                 case -ESHUTDOWN:                // hardware gone
 967                         break;
 968
 969                 // like rx, tx gets controller i/o faults during khubd delays
 970                 // and so it uses the same throttling mechanism.
 971                 case -EPROTO:
 972                 case -ETIME:
 973                 case -EILSEQ:
 974                         if (!timer_pending (&dev->delay)) {
 975                                 mod_timer (&dev->delay,
 976                                         jiffies + THROTTLE_JIFFIES);
 977                                 if (netif_msg_link (dev))
 978                                         devdbg (dev, "tx throttle %d",
 979                                                         urb->status);
 980                         }
 981                         netif_stop_queue (dev->net);
 982                         break;
 983                 default:
 984                         if (netif_msg_tx_err (dev))
 985                                 devdbg (dev, "tx err %d", entry->urb->status);
 986                         break;
 987                 }
 988         }
 989
 990         urb->dev = NULL;
 991         entry->state = tx_done;
 992         defer_bh(dev, skb, &dev->txq);
 993 }
 994
 995 /*-------------------------------------------------------------------------*/
 996
 997 void usbnet_tx_timeout (struct net_device *net)
 998 {
 999         struct usbnet           *dev = netdev_priv(net);
1000
1001         unlink_urbs (dev, &dev->txq);
1002         tasklet_schedule (&dev->bh);
1003
1004         // FIXME: device recovery -- reset?
1005 }
1006 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1007
1008 /*-------------------------------------------------------------------------*/
1009
1010 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1011                                      struct net_device *net)
1012 {
1013         struct usbnet           *dev = netdev_priv(net);
1014         int                     length;
1015         struct urb              *urb = NULL;
1016         struct skb_data         *entry;
1017         struct driver_info      *info = dev->driver_info;
1018         unsigned long           flags;
1019         int retval;
1020
1021         // some devices want funky USB-level framing, for
1022         // win32 driver (usually) and/or hardware quirks
1023         if (info->tx_fixup) {
1024                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1025                 if (!skb) {
1026                         if (netif_msg_tx_err (dev))
1027                                 devdbg (dev, "can't tx_fixup skb");
1028                         goto drop;
1029                 }
1030         }
1031         length = skb->len;
1032
1033         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1034                 if (netif_msg_tx_err (dev))
1035                         devdbg (dev, "no urb");
1036                 goto drop;
1037         }
1038
1039         entry = (struct skb_data *) skb->cb;
1040         entry->urb = urb;
1041         entry->dev = dev;
1042         entry->state = tx_start;
1043         entry->length = length;
1044
1045         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1046                         skb->data, skb->len, tx_complete, skb);
1047
1048         /* don't assume the hardware handles USB_ZERO_PACKET
1049          * NOTE:  strictly conforming cdc-ether devices should expect
1050          * the ZLP here, but ignore the one-byte packet.
1051          */
1052         if ((length % dev->maxpacket) == 0) {
1053                 urb->transfer_buffer_length++;
1054                 if (skb_tailroom(skb)) {
1055                         skb->data[skb->len] = 0;
1056                         __skb_put(skb, 1);
1057                 }
1058         }
1059
1060         spin_lock_irqsave (&dev->txq.lock, flags);
1061
1062         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1063         case -EPIPE:
1064                 netif_stop_queue (net);
1065                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1066                 break;
1067         default:
1068                 if (netif_msg_tx_err (dev))
1069                         devdbg (dev, "tx: submit urb err %d", retval);
1070                 break;
1071         case 0:
1072                 net->trans_start = jiffies;
1073                 __skb_queue_tail (&dev->txq, skb);
1074                 if (dev->txq.qlen >= TX_QLEN (dev))
1075                         netif_stop_queue (net);
1076         }
1077         spin_unlock_irqrestore (&dev->txq.lock, flags);
1078
1079         if (retval) {
1080                 if (netif_msg_tx_err (dev))
1081                         devdbg (dev, "drop, code %d", retval);
1082 drop:
1083                 dev->net->stats.tx_dropped++;
1084                 if (skb)
1085                         dev_kfree_skb_any (skb);
1086                 usb_free_urb (urb);
1087         } else if (netif_msg_tx_queued (dev)) {
1088                 devdbg (dev, "> tx, len %d, type 0x%x",
1089                         length, skb->protocol);
1090         }
1091         return NETDEV_TX_OK;
1092 }
1093 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1094
1095 /*-------------------------------------------------------------------------*/
1096
1097 // tasklet (work deferred from completions, in_irq) or timer
1098
1099 static void usbnet_bh (unsigned long param)
1100 {
1101         struct usbnet           *dev = (struct usbnet *) param;
1102         struct sk_buff          *skb;
1103         struct skb_data         *entry;
1104
1105         while ((skb = skb_dequeue (&dev->done))) {
1106                 entry = (struct skb_data *) skb->cb;
1107                 switch (entry->state) {
1108                 case rx_done:
1109                         entry->state = rx_cleanup;
1110                         rx_process (dev, skb);
1111                         continue;
1112                 case tx_done:
1113                 case rx_cleanup:
1114                         usb_free_urb (entry->urb);
1115                         dev_kfree_skb (skb);
1116                         continue;
1117                 default:
1118                         devdbg (dev, "bogus skb state %d", entry->state);
1119                 }
1120         }
1121
1122         // waiting for all pending urbs to complete?
1123         if (dev->wait) {
1124                 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1125                         wake_up (dev->wait);
1126                 }
1127
1128         // or are we maybe short a few urbs?
1129         } else if (netif_running (dev->net)
1130                         && netif_device_present (dev->net)
1131                         && !timer_pending (&dev->delay)
1132                         && !test_bit (EVENT_RX_HALT, &dev->flags)) {
1133                 int     temp = dev->rxq.qlen;
1134                 int     qlen = RX_QLEN (dev);
1135
1136                 if (temp < qlen) {
1137                         struct urb      *urb;
1138                         int             i;
1139
1140                         // don't refill the queue all at once
1141                         for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1142                                 urb = usb_alloc_urb (0, GFP_ATOMIC);
1143                                 if (urb != NULL)
1144                                         rx_submit (dev, urb, GFP_ATOMIC);
1145                         }
1146                         if (temp != dev->rxq.qlen && netif_msg_link (dev))
1147                                 devdbg (dev, "rxqlen %d --> %d",
1148                                                 temp, dev->rxq.qlen);
1149                         if (dev->rxq.qlen < qlen)
1150                                 tasklet_schedule (&dev->bh);
1151                 }
1152                 if (dev->txq.qlen < TX_QLEN (dev))
1153                         netif_wake_queue (dev->net);
1154         }
1155 }
1156
1157
1158 /*-------------------------------------------------------------------------
1159  *
1160  * USB Device Driver support
1161  *
1162  *-------------------------------------------------------------------------*/
1163
1164 // precondition: never called in_interrupt
1165
1166 void usbnet_disconnect (struct usb_interface *intf)
1167 {
1168         struct usbnet           *dev;
1169         struct usb_device       *xdev;
1170         struct net_device       *net;
1171
1172         dev = usb_get_intfdata(intf);
1173         usb_set_intfdata(intf, NULL);
1174         if (!dev)
1175                 return;
1176
1177         xdev = interface_to_usbdev (intf);
1178
1179         if (netif_msg_probe (dev))
1180                 devinfo (dev, "unregister '%s' usb-%s-%s, %s",
1181                         intf->dev.driver->name,
1182                         xdev->bus->bus_name, xdev->devpath,
1183                         dev->driver_info->description);
1184
1185         net = dev->net;
1186         unregister_netdev (net);
1187
1188         /* we don't hold rtnl here ... */
1189         flush_scheduled_work ();
1190
1191         if (dev->driver_info->unbind)
1192                 dev->driver_info->unbind (dev, intf);
1193
1194         free_netdev(net);
1195         usb_put_dev (xdev);
1196 }
1197 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1198
1199 static const struct net_device_ops usbnet_netdev_ops = {
1200         .ndo_open               = usbnet_open,
1201         .ndo_stop               = usbnet_stop,
1202         .ndo_start_xmit         = usbnet_start_xmit,
1203         .ndo_tx_timeout         = usbnet_tx_timeout,
1204         .ndo_change_mtu         = usbnet_change_mtu,
1205         .ndo_set_mac_address    = eth_mac_addr,
1206         .ndo_validate_addr      = eth_validate_addr,
1207 };
1208
1209 /*-------------------------------------------------------------------------*/
1210
1211 // precondition: never called in_interrupt
1212
1213 int
1214 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1215 {
1216         struct usbnet                   *dev;
1217         struct net_device               *net;
1218         struct usb_host_interface       *interface;
1219         struct driver_info              *info;
1220         struct usb_device               *xdev;
1221         int                             status;
1222         const char                      *name;
1223
1224         name = udev->dev.driver->name;
1225         info = (struct driver_info *) prod->driver_info;
1226         if (!info) {
1227                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1228                 return -ENODEV;
1229         }
1230         xdev = interface_to_usbdev (udev);
1231         interface = udev->cur_altsetting;
1232
1233         usb_get_dev (xdev);
1234
1235         status = -ENOMEM;
1236
1237         // set up our own records
1238         net = alloc_etherdev(sizeof(*dev));
1239         if (!net) {
1240                 dbg ("can't kmalloc dev");
1241                 goto out;
1242         }
1243
1244         dev = netdev_priv(net);
1245         dev->udev = xdev;
1246         dev->intf = udev;
1247         dev->driver_info = info;
1248         dev->driver_name = name;
1249         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1250                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1251         skb_queue_head_init (&dev->rxq);
1252         skb_queue_head_init (&dev->txq);
1253         skb_queue_head_init (&dev->done);
1254         skb_queue_head_init(&dev->rxq_pause);
1255         dev->bh.func = usbnet_bh;
1256         dev->bh.data = (unsigned long) dev;
1257         INIT_WORK (&dev->kevent, kevent);
1258         dev->delay.function = usbnet_bh;
1259         dev->delay.data = (unsigned long) dev;
1260         init_timer (&dev->delay);
1261         mutex_init (&dev->phy_mutex);
1262
1263         dev->net = net;
1264         strcpy (net->name, "usb%d");
1265         memcpy (net->dev_addr, node_id, sizeof node_id);
1266
1267         /* rx and tx sides can use different message sizes;
1268          * bind() should set rx_urb_size in that case.
1269          */
1270         dev->hard_mtu = net->mtu + net->hard_header_len;
1271 #if 0
1272 // dma_supported() is deeply broken on almost all architectures
1273         // possible with some EHCI controllers
1274         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1275                 net->features |= NETIF_F_HIGHDMA;
1276 #endif
1277
1278         net->netdev_ops = &usbnet_netdev_ops;
1279         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1280         net->ethtool_ops = &usbnet_ethtool_ops;
1281
1282         // allow device-specific bind/init procedures
1283         // NOTE net->name still not usable ...
1284         if (info->bind) {
1285                 status = info->bind (dev, udev);
1286                 if (status < 0)
1287                         goto out1;
1288
1289                 // heuristic:  "usb%d" for links we know are two-host,
1290                 // else "eth%d" when there's reasonable doubt.  userspace
1291                 // can rename the link if it knows better.
1292                 if ((dev->driver_info->flags & FLAG_ETHER) != 0
1293                                 && (net->dev_addr [0] & 0x02) == 0)
1294                         strcpy (net->name, "eth%d");
1295                 /* WLAN devices should always be named "wlan%d" */
1296                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1297                         strcpy(net->name, "wlan%d");
1298
1299                 /* maybe the remote can't receive an Ethernet MTU */
1300                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1301                         net->mtu = dev->hard_mtu - net->hard_header_len;
1302         } else if (!info->in || !info->out)
1303                 status = usbnet_get_endpoints (dev, udev);
1304         else {
1305                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1306                 dev->out = usb_sndbulkpipe (xdev, info->out);
1307                 if (!(info->flags & FLAG_NO_SETINT))
1308                         status = usb_set_interface (xdev,
1309                                 interface->desc.bInterfaceNumber,
1310                                 interface->desc.bAlternateSetting);
1311                 else
1312                         status = 0;
1313
1314         }
1315         if (status >= 0 && dev->status)
1316                 status = init_status (dev, udev);
1317         if (status < 0)
1318                 goto out3;
1319
1320         if (!dev->rx_urb_size)
1321                 dev->rx_urb_size = dev->hard_mtu;
1322         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1323
1324         SET_NETDEV_DEV(net, &udev->dev);
1325         status = register_netdev (net);
1326         if (status)
1327                 goto out3;
1328         if (netif_msg_probe (dev))
1329                 devinfo (dev, "register '%s' at usb-%s-%s, %s, %pM",
1330                         udev->dev.driver->name,
1331                         xdev->bus->bus_name, xdev->devpath,
1332                         dev->driver_info->description,
1333                         net->dev_addr);
1334
1335         // ok, it's ready to go.
1336         usb_set_intfdata (udev, dev);
1337
1338         // start as if the link is up
1339         netif_device_attach (net);
1340
1341         return 0;
1342
1343 out3:
1344         if (info->unbind)
1345                 info->unbind (dev, udev);
1346 out1:
1347         free_netdev(net);
1348 out:
1349         usb_put_dev(xdev);
1350         return status;
1351 }
1352 EXPORT_SYMBOL_GPL(usbnet_probe);
1353
1354 /*-------------------------------------------------------------------------*/
1355
1356 /*
1357  * suspend the whole driver as soon as the first interface is suspended
1358  * resume only when the last interface is resumed
1359  */
1360
1361 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1362 {
1363         struct usbnet           *dev = usb_get_intfdata(intf);
1364
1365         if (!dev->suspend_count++) {
1366                 /*
1367                  * accelerate emptying of the rx and queues, to avoid
1368                  * having everything error out.
1369                  */
1370                 netif_device_detach (dev->net);
1371                 (void) unlink_urbs (dev, &dev->rxq);
1372                 (void) unlink_urbs (dev, &dev->txq);
1373                 /*
1374                  * reattach so runtime management can use and
1375                  * wake the device
1376                  */
1377                 netif_device_attach (dev->net);
1378         }
1379         return 0;
1380 }
1381 EXPORT_SYMBOL_GPL(usbnet_suspend);
1382
1383 int usbnet_resume (struct usb_interface *intf)
1384 {
1385         struct usbnet           *dev = usb_get_intfdata(intf);
1386
1387         if (!--dev->suspend_count)
1388                 tasklet_schedule (&dev->bh);
1389
1390         return 0;
1391 }
1392 EXPORT_SYMBOL_GPL(usbnet_resume);
1393
1394
1395 /*-------------------------------------------------------------------------*/
1396
1397 static int __init usbnet_init(void)
1398 {
1399         /* compiler should optimize this out */
1400         BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1401                         < sizeof (struct skb_data));
1402
1403         random_ether_addr(node_id);
1404         return 0;
1405 }
1406 module_init(usbnet_init);
1407
1408 static void __exit usbnet_exit(void)
1409 {
1410 }
1411 module_exit(usbnet_exit);
1412
1413 MODULE_AUTHOR("David Brownell");
1414 MODULE_DESCRIPTION("USB network driver framework");
1415 MODULE_LICENSE("GPL");