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 #include <linux/slab.h>
  47 #include <linux/kernel.h>
  48
  49 #define DRIVER_VERSION          "22-Aug-2005"
  50
  51
  52 /*-------------------------------------------------------------------------*/
  53
  54 /*
  55  * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  56  * Several dozen bytes of IPv4 data can fit in two such transactions.
  57  * One maximum size Ethernet packet takes twenty four of them.
  58  * For high speed, each frame comfortably fits almost 36 max size
  59  * Ethernet packets (so queues should be bigger).
  60  *
  61  * REVISIT qlens should be members of 'struct usbnet'; the goal is to
  62  * let the USB host controller be busy for 5msec or more before an irq
  63  * is required, under load.  Jumbograms change the equation.
  64  */
  65 #define RX_MAX_QUEUE_MEMORY (60 * 1518)
  66 #define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  67                         (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
  68 #define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  69                         (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
  70
  71 // reawaken network queue this soon after stopping; else watchdog barks
  72 #define TX_TIMEOUT_JIFFIES      (5*HZ)
  73
  74 // throttle rx/tx briefly after some faults, so khubd might disconnect()
  75 // us (it polls at HZ/4 usually) before we report too many false errors.
  76 #define THROTTLE_JIFFIES        (HZ/8)
  77
  78 // between wakeups
  79 #define UNLINK_TIMEOUT_MS       3
  80
  81 /*-------------------------------------------------------------------------*/
  82
  83 // randomly generated ethernet address
  84 static u8       node_id [ETH_ALEN];
  85
  86 static const char driver_name [] = "usbnet";
  87
  88 /* use ethtool to change the level for any given device */
  89 static int msg_level = -1;
  90 module_param (msg_level, int, 0);
  91 MODULE_PARM_DESC (msg_level, "Override default message level");
  92
  93 /*-------------------------------------------------------------------------*/
  94
  95 /* handles CDC Ethernet and many other network "bulk data" interfaces */
  96 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  97 {
  98         int                             tmp;
  99         struct usb_host_interface       *alt = NULL;
 100         struct usb_host_endpoint        *in = NULL, *out = NULL;
 101         struct usb_host_endpoint        *status = NULL;
 102
 103         for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 104                 unsigned        ep;
 105
 106                 in = out = status = NULL;
 107                 alt = intf->altsetting + tmp;
 108
 109                 /* take the first altsetting with in-bulk + out-bulk;
 110                  * remember any status endpoint, just in case;
 111                  * ignore other endpoints and altsetttings.
 112                  */
 113                 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 114                         struct usb_host_endpoint        *e;
 115                         int                             intr = 0;
 116
 117                         e = alt->endpoint + ep;
 118                         switch (e->desc.bmAttributes) {
 119                         case USB_ENDPOINT_XFER_INT:
 120                                 if (!usb_endpoint_dir_in(&e->desc))
 121                                         continue;
 122                                 intr = 1;
 123                                 /* FALLTHROUGH */
 124                         case USB_ENDPOINT_XFER_BULK:
 125                                 break;
 126                         default:
 127                                 continue;
 128                         }
 129                         if (usb_endpoint_dir_in(&e->desc)) {
 130                                 if (!intr && !in)
 131                                         in = e;
 132                                 else if (intr && !status)
 133                                         status = e;
 134                         } else {
 135                                 if (!out)
 136                                         out = e;
 137                         }
 138                 }
 139                 if (in && out)
 140                         break;
 141         }
 142         if (!alt || !in || !out)
 143                 return -EINVAL;
 144
 145         if (alt->desc.bAlternateSetting != 0 ||
 146             !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 147                 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 148                                 alt->desc.bAlternateSetting);
 149                 if (tmp < 0)
 150                         return tmp;
 151         }
 152
 153         dev->in = usb_rcvbulkpipe (dev->udev,
 154                         in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 155         dev->out = usb_sndbulkpipe (dev->udev,
 156                         out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 157         dev->status = status;
 158         return 0;
 159 }
 160 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 161
 162 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 163 {
 164         int             tmp, i;
 165         unsigned char   buf [13];
 166
 167         tmp = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 168         if (tmp != 12) {
 169                 dev_dbg(&dev->udev->dev,
 170                         "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 171                 if (tmp >= 0)
 172                         tmp = -EINVAL;
 173                 return tmp;
 174         }
 175         for (i = tmp = 0; i < 6; i++, tmp += 2)
 176                 dev->net->dev_addr [i] =
 177                         (hex_to_bin(buf[tmp]) << 4) + hex_to_bin(buf[tmp + 1]);
 178         return 0;
 179 }
 180 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 181
 182 static void intr_complete (struct urb *urb);
 183
 184 static int init_status (struct usbnet *dev, struct usb_interface *intf)
 185 {
 186         char            *buf = NULL;
 187         unsigned        pipe = 0;
 188         unsigned        maxp;
 189         unsigned        period;
 190
 191         if (!dev->driver_info->status)
 192                 return 0;
 193
 194         pipe = usb_rcvintpipe (dev->udev,
 195                         dev->status->desc.bEndpointAddress
 196                                 & USB_ENDPOINT_NUMBER_MASK);
 197         maxp = usb_maxpacket (dev->udev, pipe, 0);
 198
 199         /* avoid 1 msec chatter:  min 8 msec poll rate */
 200         period = max ((int) dev->status->desc.bInterval,
 201                 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 202
 203         buf = kmalloc (maxp, GFP_KERNEL);
 204         if (buf) {
 205                 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 206                 if (!dev->interrupt) {
 207                         kfree (buf);
 208                         return -ENOMEM;
 209                 } else {
 210                         usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 211                                 buf, maxp, intr_complete, dev, period);
 212                         dev_dbg(&intf->dev,
 213                                 "status ep%din, %d bytes period %d\n",
 214                                 usb_pipeendpoint(pipe), maxp, period);
 215                 }
 216         }
 217         return 0;
 218 }
 219
 220 /* Passes this packet up the stack, updating its accounting.
 221  * Some link protocols batch packets, so their rx_fixup paths
 222  * can return clones as well as just modify the original skb.
 223  */
 224 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 225 {
 226         int     status;
 227
 228         if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 229                 skb_queue_tail(&dev->rxq_pause, skb);
 230                 return;
 231         }
 232
 233         skb->protocol = eth_type_trans (skb, dev->net);
 234         dev->net->stats.rx_packets++;
 235         dev->net->stats.rx_bytes += skb->len;
 236
 237         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 238                   skb->len + sizeof (struct ethhdr), skb->protocol);
 239         memset (skb->cb, 0, sizeof (struct skb_data));
 240         status = netif_rx (skb);
 241         if (status != NET_RX_SUCCESS)
 242                 netif_dbg(dev, rx_err, dev->net,
 243                           "netif_rx status %d\n", status);
 244 }
 245 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 246
 247 \f
 248 /*-------------------------------------------------------------------------
 249  *
 250  * Network Device Driver (peer link to "Host Device", from USB host)
 251  *
 252  *-------------------------------------------------------------------------*/
 253
 254 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 255 {
 256         struct usbnet   *dev = netdev_priv(net);
 257         int             ll_mtu = new_mtu + net->hard_header_len;
 258         int             old_hard_mtu = dev->hard_mtu;
 259         int             old_rx_urb_size = dev->rx_urb_size;
 260
 261         if (new_mtu <= 0)
 262                 return -EINVAL;
 263         // no second zero-length packet read wanted after mtu-sized packets
 264         if ((ll_mtu % dev->maxpacket) == 0)
 265                 return -EDOM;
 266         net->mtu = new_mtu;
 267
 268         dev->hard_mtu = net->mtu + net->hard_header_len;
 269         if (dev->rx_urb_size == old_hard_mtu) {
 270                 dev->rx_urb_size = dev->hard_mtu;
 271                 if (dev->rx_urb_size > old_rx_urb_size)
 272                         usbnet_unlink_rx_urbs(dev);
 273         }
 274
 275         return 0;
 276 }
 277 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 278
 279 /*-------------------------------------------------------------------------*/
 280
 281 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 282  * completion callbacks.  2.5 should have fixed those bugs...
 283  */
 284
 285 static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 286 {
 287         unsigned long           flags;
 288
 289         spin_lock_irqsave(&list->lock, flags);
 290         __skb_unlink(skb, list);
 291         spin_unlock(&list->lock);
 292         spin_lock(&dev->done.lock);
 293         __skb_queue_tail(&dev->done, skb);
 294         if (dev->done.qlen == 1)
 295                 tasklet_schedule(&dev->bh);
 296         spin_unlock_irqrestore(&dev->done.lock, flags);
 297 }
 298
 299 /* some work can't be done in tasklets, so we use keventd
 300  *
 301  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 302  * but tasklet_schedule() doesn't.  hope the failure is rare.
 303  */
 304 void usbnet_defer_kevent (struct usbnet *dev, int work)
 305 {
 306         set_bit (work, &dev->flags);
 307         if (!schedule_work (&dev->kevent))
 308                 netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 309         else
 310                 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 311 }
 312 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 313
 314 /*-------------------------------------------------------------------------*/
 315
 316 static void rx_complete (struct urb *urb);
 317
 318 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 319 {
 320         struct sk_buff          *skb;
 321         struct skb_data         *entry;
 322         int                     retval = 0;
 323         unsigned long           lockflags;
 324         size_t                  size = dev->rx_urb_size;
 325
 326         if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
 327                 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 328                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 329                 usb_free_urb (urb);
 330                 return -ENOMEM;
 331         }
 332         skb_reserve (skb, NET_IP_ALIGN);
 333
 334         entry = (struct skb_data *) skb->cb;
 335         entry->urb = urb;
 336         entry->dev = dev;
 337         entry->state = rx_start;
 338         entry->length = 0;
 339
 340         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 341                 skb->data, size, rx_complete, skb);
 342
 343         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 344
 345         if (netif_running (dev->net) &&
 346             netif_device_present (dev->net) &&
 347             !test_bit (EVENT_RX_HALT, &dev->flags) &&
 348             !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 349                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 350                 case -EPIPE:
 351                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 352                         break;
 353                 case -ENOMEM:
 354                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 355                         break;
 356                 case -ENODEV:
 357                         netif_dbg(dev, ifdown, dev->net, "device gone\n");
 358                         netif_device_detach (dev->net);
 359                         break;
 360                 case -EHOSTUNREACH:
 361                         retval = -ENOLINK;
 362                         break;
 363                 default:
 364                         netif_dbg(dev, rx_err, dev->net,
 365                                   "rx submit, %d\n", retval);
 366                         tasklet_schedule (&dev->bh);
 367                         break;
 368                 case 0:
 369                         __skb_queue_tail (&dev->rxq, skb);
 370                 }
 371         } else {
 372                 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 373                 retval = -ENOLINK;
 374         }
 375         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 376         if (retval) {
 377                 dev_kfree_skb_any (skb);
 378                 usb_free_urb (urb);
 379         }
 380         return retval;
 381 }
 382
 383
 384 /*-------------------------------------------------------------------------*/
 385
 386 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 387 {
 388         if (dev->driver_info->rx_fixup &&
 389             !dev->driver_info->rx_fixup (dev, skb))
 390                 goto error;
 391         // else network stack removes extra byte if we forced a short packet
 392
 393         if (skb->len)
 394                 usbnet_skb_return (dev, skb);
 395         else {
 396                 netif_dbg(dev, rx_err, dev->net, "drop\n");
 397 error:
 398                 dev->net->stats.rx_errors++;
 399                 skb_queue_tail (&dev->done, skb);
 400         }
 401 }
 402
 403 /*-------------------------------------------------------------------------*/
 404
 405 static void rx_complete (struct urb *urb)
 406 {
 407         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 408         struct skb_data         *entry = (struct skb_data *) skb->cb;
 409         struct usbnet           *dev = entry->dev;
 410         int                     urb_status = urb->status;
 411
 412         skb_put (skb, urb->actual_length);
 413         entry->state = rx_done;
 414         entry->urb = NULL;
 415
 416         switch (urb_status) {
 417         /* success */
 418         case 0:
 419                 if (skb->len < dev->net->hard_header_len) {
 420                         entry->state = rx_cleanup;
 421                         dev->net->stats.rx_errors++;
 422                         dev->net->stats.rx_length_errors++;
 423                         netif_dbg(dev, rx_err, dev->net,
 424                                   "rx length %d\n", skb->len);
 425                 }
 426                 break;
 427
 428         /* stalls need manual reset. this is rare ... except that
 429          * when going through USB 2.0 TTs, unplug appears this way.
 430          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 431          * storm, recovering as needed.
 432          */
 433         case -EPIPE:
 434                 dev->net->stats.rx_errors++;
 435                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 436                 // FALLTHROUGH
 437
 438         /* software-driven interface shutdown */
 439         case -ECONNRESET:               /* async unlink */
 440         case -ESHUTDOWN:                /* hardware gone */
 441                 netif_dbg(dev, ifdown, dev->net,
 442                           "rx shutdown, code %d\n", urb_status);
 443                 goto block;
 444
 445         /* we get controller i/o faults during khubd disconnect() delays.
 446          * throttle down resubmits, to avoid log floods; just temporarily,
 447          * so we still recover when the fault isn't a khubd delay.
 448          */
 449         case -EPROTO:
 450         case -ETIME:
 451         case -EILSEQ:
 452                 dev->net->stats.rx_errors++;
 453                 if (!timer_pending (&dev->delay)) {
 454                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 455                         netif_dbg(dev, link, dev->net,
 456                                   "rx throttle %d\n", urb_status);
 457                 }
 458 block:
 459                 entry->state = rx_cleanup;
 460                 entry->urb = urb;
 461                 urb = NULL;
 462                 break;
 463
 464         /* data overrun ... flush fifo? */
 465         case -EOVERFLOW:
 466                 dev->net->stats.rx_over_errors++;
 467                 // FALLTHROUGH
 468
 469         default:
 470                 entry->state = rx_cleanup;
 471                 dev->net->stats.rx_errors++;
 472                 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 473                 break;
 474         }
 475
 476         defer_bh(dev, skb, &dev->rxq);
 477
 478         if (urb) {
 479                 if (netif_running (dev->net) &&
 480                     !test_bit (EVENT_RX_HALT, &dev->flags)) {
 481                         rx_submit (dev, urb, GFP_ATOMIC);
 482                         return;
 483                 }
 484                 usb_free_urb (urb);
 485         }
 486         netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 487 }
 488
 489 static void intr_complete (struct urb *urb)
 490 {
 491         struct usbnet   *dev = urb->context;
 492         int             status = urb->status;
 493
 494         switch (status) {
 495         /* success */
 496         case 0:
 497                 dev->driver_info->status(dev, urb);
 498                 break;
 499
 500         /* software-driven interface shutdown */
 501         case -ENOENT:           /* urb killed */
 502         case -ESHUTDOWN:        /* hardware gone */
 503                 netif_dbg(dev, ifdown, dev->net,
 504                           "intr shutdown, code %d\n", status);
 505                 return;
 506
 507         /* NOTE:  not throttling like RX/TX, since this endpoint
 508          * already polls infrequently
 509          */
 510         default:
 511                 netdev_dbg(dev->net, "intr status %d\n", status);
 512                 break;
 513         }
 514
 515         if (!netif_running (dev->net))
 516                 return;
 517
 518         memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 519         status = usb_submit_urb (urb, GFP_ATOMIC);
 520         if (status != 0)
 521                 netif_err(dev, timer, dev->net,
 522                           "intr resubmit --> %d\n", status);
 523 }
 524
 525 /*-------------------------------------------------------------------------*/
 526 void usbnet_pause_rx(struct usbnet *dev)
 527 {
 528         set_bit(EVENT_RX_PAUSED, &dev->flags);
 529
 530         netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 531 }
 532 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 533
 534 void usbnet_resume_rx(struct usbnet *dev)
 535 {
 536         struct sk_buff *skb;
 537         int num = 0;
 538
 539         clear_bit(EVENT_RX_PAUSED, &dev->flags);
 540
 541         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 542                 usbnet_skb_return(dev, skb);
 543                 num++;
 544         }
 545
 546         tasklet_schedule(&dev->bh);
 547
 548         netif_dbg(dev, rx_status, dev->net,
 549                   "paused rx queue disabled, %d skbs requeued\n", num);
 550 }
 551 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 552
 553 void usbnet_purge_paused_rxq(struct usbnet *dev)
 554 {
 555         skb_queue_purge(&dev->rxq_pause);
 556 }
 557 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 558
 559 /*-------------------------------------------------------------------------*/
 560
 561 // unlink pending rx/tx; completion handlers do all other cleanup
 562
 563 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 564 {
 565         unsigned long           flags;
 566         struct sk_buff          *skb, *skbnext;
 567         int                     count = 0;
 568
 569         spin_lock_irqsave (&q->lock, flags);
 570         skb_queue_walk_safe(q, skb, skbnext) {
 571                 struct skb_data         *entry;
 572                 struct urb              *urb;
 573                 int                     retval;
 574
 575                 entry = (struct skb_data *) skb->cb;
 576                 urb = entry->urb;
 577
 578                 // during some PM-driven resume scenarios,
 579                 // these (async) unlinks complete immediately
 580                 retval = usb_unlink_urb (urb);
 581                 if (retval != -EINPROGRESS && retval != 0)
 582                         netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 583                 else
 584                         count++;
 585         }
 586         spin_unlock_irqrestore (&q->lock, flags);
 587         return count;
 588 }
 589
 590 // Flush all pending rx urbs
 591 // minidrivers may need to do this when the MTU changes
 592
 593 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 594 {
 595         if (netif_running(dev->net)) {
 596                 (void) unlink_urbs (dev, &dev->rxq);
 597                 tasklet_schedule(&dev->bh);
 598         }
 599 }
 600 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 601
 602 /*-------------------------------------------------------------------------*/
 603
 604 // precondition: never called in_interrupt
 605 static void usbnet_terminate_urbs(struct usbnet *dev)
 606 {
 607         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(unlink_wakeup);
 608         DECLARE_WAITQUEUE(wait, current);
 609         int temp;
 610
 611         /* ensure there are no more active urbs */
 612         add_wait_queue(&unlink_wakeup, &wait);
 613         set_current_state(TASK_UNINTERRUPTIBLE);
 614         dev->wait = &unlink_wakeup;
 615         temp = unlink_urbs(dev, &dev->txq) +
 616                 unlink_urbs(dev, &dev->rxq);
 617
 618         /* maybe wait for deletions to finish. */
 619         while (!skb_queue_empty(&dev->rxq)
 620                 && !skb_queue_empty(&dev->txq)
 621                 && !skb_queue_empty(&dev->done)) {
 622                         schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 623                         set_current_state(TASK_UNINTERRUPTIBLE);
 624                         netif_dbg(dev, ifdown, dev->net,
 625                                   "waited for %d urb completions\n", temp);
 626         }
 627         set_current_state(TASK_RUNNING);
 628         dev->wait = NULL;
 629         remove_wait_queue(&unlink_wakeup, &wait);
 630 }
 631
 632 int usbnet_stop (struct net_device *net)
 633 {
 634         struct usbnet           *dev = netdev_priv(net);
 635         struct driver_info      *info = dev->driver_info;
 636         int                     retval;
 637
 638         netif_stop_queue (net);
 639
 640         netif_info(dev, ifdown, dev->net,
 641                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 642                    net->stats.rx_packets, net->stats.tx_packets,
 643                    net->stats.rx_errors, net->stats.tx_errors);
 644
 645         /* allow minidriver to stop correctly (wireless devices to turn off
 646          * radio etc) */
 647         if (info->stop) {
 648                 retval = info->stop(dev);
 649                 if (retval < 0)
 650                         netif_info(dev, ifdown, dev->net,
 651                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
 652                                    retval,
 653                                    dev->udev->bus->bus_name, dev->udev->devpath,
 654                                    info->description);
 655         }
 656
 657         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 658                 usbnet_terminate_urbs(dev);
 659
 660         usb_kill_urb(dev->interrupt);
 661
 662         usbnet_purge_paused_rxq(dev);
 663
 664         /* deferred work (task, timer, softirq) must also stop.
 665          * can't flush_scheduled_work() until we drop rtnl (later),
 666          * else workers could deadlock; so make workers a NOP.
 667          */
 668         dev->flags = 0;
 669         del_timer_sync (&dev->delay);
 670         tasklet_kill (&dev->bh);
 671         if (info->manage_power)
 672                 info->manage_power(dev, 0);
 673         else
 674                 usb_autopm_put_interface(dev->intf);
 675
 676         return 0;
 677 }
 678 EXPORT_SYMBOL_GPL(usbnet_stop);
 679
 680 /*-------------------------------------------------------------------------*/
 681
 682 // posts reads, and enables write queuing
 683
 684 // precondition: never called in_interrupt
 685
 686 int usbnet_open (struct net_device *net)
 687 {
 688         struct usbnet           *dev = netdev_priv(net);
 689         int                     retval;
 690         struct driver_info      *info = dev->driver_info;
 691
 692         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 693                 netif_info(dev, ifup, dev->net,
 694                            "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 695                            retval,
 696                            dev->udev->bus->bus_name,
 697                            dev->udev->devpath,
 698                            info->description);
 699                 goto done_nopm;
 700         }
 701
 702         // put into "known safe" state
 703         if (info->reset && (retval = info->reset (dev)) < 0) {
 704                 netif_info(dev, ifup, dev->net,
 705                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 706                            retval,
 707                            dev->udev->bus->bus_name,
 708                            dev->udev->devpath,
 709                            info->description);
 710                 goto done;
 711         }
 712
 713         // insist peer be connected
 714         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 715                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 716                 goto done;
 717         }
 718
 719         /* start any status interrupt transfer */
 720         if (dev->interrupt) {
 721                 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 722                 if (retval < 0) {
 723                         netif_err(dev, ifup, dev->net,
 724                                   "intr submit %d\n", retval);
 725                         goto done;
 726                 }
 727         }
 728
 729         netif_start_queue (net);
 730         netif_info(dev, ifup, dev->net,
 731                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 732                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 733                    dev->net->mtu,
 734                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 735                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 736                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 737                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 738                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 739                    "simple");
 740
 741         // delay posting reads until we're fully open
 742         tasklet_schedule (&dev->bh);
 743         if (info->manage_power) {
 744                 retval = info->manage_power(dev, 1);
 745                 if (retval < 0)
 746                         goto done;
 747                 usb_autopm_put_interface(dev->intf);
 748         }
 749         return retval;
 750
 751 done:
 752         usb_autopm_put_interface(dev->intf);
 753 done_nopm:
 754         return retval;
 755 }
 756 EXPORT_SYMBOL_GPL(usbnet_open);
 757
 758 /*-------------------------------------------------------------------------*/
 759
 760 /* ethtool methods; minidrivers may need to add some more, but
 761  * they'll probably want to use this base set.
 762  */
 763
 764 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 765 {
 766         struct usbnet *dev = netdev_priv(net);
 767
 768         if (!dev->mii.mdio_read)
 769                 return -EOPNOTSUPP;
 770
 771         return mii_ethtool_gset(&dev->mii, cmd);
 772 }
 773 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 774
 775 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 776 {
 777         struct usbnet *dev = netdev_priv(net);
 778         int retval;
 779
 780         if (!dev->mii.mdio_write)
 781                 return -EOPNOTSUPP;
 782
 783         retval = mii_ethtool_sset(&dev->mii, cmd);
 784
 785         /* link speed/duplex might have changed */
 786         if (dev->driver_info->link_reset)
 787                 dev->driver_info->link_reset(dev);
 788
 789         return retval;
 790
 791 }
 792 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 793
 794 u32 usbnet_get_link (struct net_device *net)
 795 {
 796         struct usbnet *dev = netdev_priv(net);
 797
 798         /* If a check_connect is defined, return its result */
 799         if (dev->driver_info->check_connect)
 800                 return dev->driver_info->check_connect (dev) == 0;
 801
 802         /* if the device has mii operations, use those */
 803         if (dev->mii.mdio_read)
 804                 return mii_link_ok(&dev->mii);
 805
 806         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 807         return ethtool_op_get_link(net);
 808 }
 809 EXPORT_SYMBOL_GPL(usbnet_get_link);
 810
 811 int usbnet_nway_reset(struct net_device *net)
 812 {
 813         struct usbnet *dev = netdev_priv(net);
 814
 815         if (!dev->mii.mdio_write)
 816                 return -EOPNOTSUPP;
 817
 818         return mii_nway_restart(&dev->mii);
 819 }
 820 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 821
 822 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 823 {
 824         struct usbnet *dev = netdev_priv(net);
 825
 826         strncpy (info->driver, dev->driver_name, sizeof info->driver);
 827         strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 828         strncpy (info->fw_version, dev->driver_info->description,
 829                 sizeof info->fw_version);
 830         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 831 }
 832 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 833
 834 u32 usbnet_get_msglevel (struct net_device *net)
 835 {
 836         struct usbnet *dev = netdev_priv(net);
 837
 838         return dev->msg_enable;
 839 }
 840 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 841
 842 void usbnet_set_msglevel (struct net_device *net, u32 level)
 843 {
 844         struct usbnet *dev = netdev_priv(net);
 845
 846         dev->msg_enable = level;
 847 }
 848 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 849
 850 /* drivers may override default ethtool_ops in their bind() routine */
 851 static const struct ethtool_ops usbnet_ethtool_ops = {
 852         .get_settings           = usbnet_get_settings,
 853         .set_settings           = usbnet_set_settings,
 854         .get_link               = usbnet_get_link,
 855         .nway_reset             = usbnet_nway_reset,
 856         .get_drvinfo            = usbnet_get_drvinfo,
 857         .get_msglevel           = usbnet_get_msglevel,
 858         .set_msglevel           = usbnet_set_msglevel,
 859 };
 860
 861 /*-------------------------------------------------------------------------*/
 862
 863 /* work that cannot be done in interrupt context uses keventd.
 864  *
 865  * NOTE:  with 2.5 we could do more of this using completion callbacks,
 866  * especially now that control transfers can be queued.
 867  */
 868 static void
 869 kevent (struct work_struct *work)
 870 {
 871         struct usbnet           *dev =
 872                 container_of(work, struct usbnet, kevent);
 873         int                     status;
 874
 875         /* usb_clear_halt() needs a thread context */
 876         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 877                 unlink_urbs (dev, &dev->txq);
 878                 status = usb_autopm_get_interface(dev->intf);
 879                 if (status < 0)
 880                         goto fail_pipe;
 881                 status = usb_clear_halt (dev->udev, dev->out);
 882                 usb_autopm_put_interface(dev->intf);
 883                 if (status < 0 &&
 884                     status != -EPIPE &&
 885                     status != -ESHUTDOWN) {
 886                         if (netif_msg_tx_err (dev))
 887 fail_pipe:
 888                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
 889                                            status);
 890                 } else {
 891                         clear_bit (EVENT_TX_HALT, &dev->flags);
 892                         if (status != -ESHUTDOWN)
 893                                 netif_wake_queue (dev->net);
 894                 }
 895         }
 896         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 897                 unlink_urbs (dev, &dev->rxq);
 898                 status = usb_autopm_get_interface(dev->intf);
 899                 if (status < 0)
 900                         goto fail_halt;
 901                 status = usb_clear_halt (dev->udev, dev->in);
 902                 usb_autopm_put_interface(dev->intf);
 903                 if (status < 0 &&
 904                     status != -EPIPE &&
 905                     status != -ESHUTDOWN) {
 906                         if (netif_msg_rx_err (dev))
 907 fail_halt:
 908                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
 909                                            status);
 910                 } else {
 911                         clear_bit (EVENT_RX_HALT, &dev->flags);
 912                         tasklet_schedule (&dev->bh);
 913                 }
 914         }
 915
 916         /* tasklet could resubmit itself forever if memory is tight */
 917         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 918                 struct urb      *urb = NULL;
 919                 int resched = 1;
 920
 921                 if (netif_running (dev->net))
 922                         urb = usb_alloc_urb (0, GFP_KERNEL);
 923                 else
 924                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 925                 if (urb != NULL) {
 926                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 927                         status = usb_autopm_get_interface(dev->intf);
 928                         if (status < 0)
 929                                 goto fail_lowmem;
 930                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
 931                                 resched = 0;
 932                         usb_autopm_put_interface(dev->intf);
 933 fail_lowmem:
 934                         if (resched)
 935                                 tasklet_schedule (&dev->bh);
 936                 }
 937         }
 938
 939         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 940                 struct driver_info      *info = dev->driver_info;
 941                 int                     retval = 0;
 942
 943                 clear_bit (EVENT_LINK_RESET, &dev->flags);
 944                 status = usb_autopm_get_interface(dev->intf);
 945                 if (status < 0)
 946                         goto skip_reset;
 947                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 948                         usb_autopm_put_interface(dev->intf);
 949 skip_reset:
 950                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
 951                                     retval,
 952                                     dev->udev->bus->bus_name,
 953                                     dev->udev->devpath,
 954                                     info->description);
 955                 } else {
 956                         usb_autopm_put_interface(dev->intf);
 957                 }
 958         }
 959
 960         if (dev->flags)
 961                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
 962 }
 963
 964 /*-------------------------------------------------------------------------*/
 965
 966 static void tx_complete (struct urb *urb)
 967 {
 968         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 969         struct skb_data         *entry = (struct skb_data *) skb->cb;
 970         struct usbnet           *dev = entry->dev;
 971
 972         if (urb->status == 0) {
 973                 dev->net->stats.tx_packets++;
 974                 dev->net->stats.tx_bytes += entry->length;
 975         } else {
 976                 dev->net->stats.tx_errors++;
 977
 978                 switch (urb->status) {
 979                 case -EPIPE:
 980                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
 981                         break;
 982
 983                 /* software-driven interface shutdown */
 984                 case -ECONNRESET:               // async unlink
 985                 case -ESHUTDOWN:                // hardware gone
 986                         break;
 987
 988                 // like rx, tx gets controller i/o faults during khubd delays
 989                 // and so it uses the same throttling mechanism.
 990                 case -EPROTO:
 991                 case -ETIME:
 992                 case -EILSEQ:
 993                         usb_mark_last_busy(dev->udev);
 994                         if (!timer_pending (&dev->delay)) {
 995                                 mod_timer (&dev->delay,
 996                                         jiffies + THROTTLE_JIFFIES);
 997                                 netif_dbg(dev, link, dev->net,
 998                                           "tx throttle %d\n", urb->status);
 999                         }
1000                         netif_stop_queue (dev->net);
1001                         break;
1002                 default:
1003                         netif_dbg(dev, tx_err, dev->net,
1004                                   "tx err %d\n", entry->urb->status);
1005                         break;
1006                 }
1007         }
1008
1009         usb_autopm_put_interface_async(dev->intf);
1010         urb->dev = NULL;
1011         entry->state = tx_done;
1012         defer_bh(dev, skb, &dev->txq);
1013 }
1014
1015 /*-------------------------------------------------------------------------*/
1016
1017 void usbnet_tx_timeout (struct net_device *net)
1018 {
1019         struct usbnet           *dev = netdev_priv(net);
1020
1021         unlink_urbs (dev, &dev->txq);
1022         tasklet_schedule (&dev->bh);
1023
1024         // FIXME: device recovery -- reset?
1025 }
1026 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1027
1028 /*-------------------------------------------------------------------------*/
1029
1030 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1031                                      struct net_device *net)
1032 {
1033         struct usbnet           *dev = netdev_priv(net);
1034         int                     length;
1035         struct urb              *urb = NULL;
1036         struct skb_data         *entry;
1037         struct driver_info      *info = dev->driver_info;
1038         unsigned long           flags;
1039         int retval;
1040
1041         // some devices want funky USB-level framing, for
1042         // win32 driver (usually) and/or hardware quirks
1043         if (info->tx_fixup) {
1044                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1045                 if (!skb) {
1046                         netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1047                         goto drop;
1048                 }
1049         }
1050         length = skb->len;
1051
1052         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1053                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1054                 goto drop;
1055         }
1056
1057         entry = (struct skb_data *) skb->cb;
1058         entry->urb = urb;
1059         entry->dev = dev;
1060         entry->state = tx_start;
1061         entry->length = length;
1062
1063         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1064                         skb->data, skb->len, tx_complete, skb);
1065
1066         /* don't assume the hardware handles USB_ZERO_PACKET
1067          * NOTE:  strictly conforming cdc-ether devices should expect
1068          * the ZLP here, but ignore the one-byte packet.
1069          */
1070         if (length % dev->maxpacket == 0) {
1071                 if (!(info->flags & FLAG_SEND_ZLP)) {
1072                         urb->transfer_buffer_length++;
1073                         if (skb_tailroom(skb)) {
1074                                 skb->data[skb->len] = 0;
1075                                 __skb_put(skb, 1);
1076                         }
1077                 } else
1078                         urb->transfer_flags |= URB_ZERO_PACKET;
1079         }
1080
1081         spin_lock_irqsave(&dev->txq.lock, flags);
1082         retval = usb_autopm_get_interface_async(dev->intf);
1083         if (retval < 0) {
1084                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1085                 goto drop;
1086         }
1087
1088 #ifdef CONFIG_PM
1089         /* if this triggers the device is still a sleep */
1090         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1091                 /* transmission will be done in resume */
1092                 usb_anchor_urb(urb, &dev->deferred);
1093                 /* no use to process more packets */
1094                 netif_stop_queue(net);
1095                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1096                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1097                 goto deferred;
1098         }
1099 #endif
1100
1101         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1102         case -EPIPE:
1103                 netif_stop_queue (net);
1104                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1105                 usb_autopm_put_interface_async(dev->intf);
1106                 break;
1107         default:
1108                 usb_autopm_put_interface_async(dev->intf);
1109                 netif_dbg(dev, tx_err, dev->net,
1110                           "tx: submit urb err %d\n", retval);
1111                 break;
1112         case 0:
1113                 net->trans_start = jiffies;
1114                 __skb_queue_tail (&dev->txq, skb);
1115                 if (dev->txq.qlen >= TX_QLEN (dev))
1116                         netif_stop_queue (net);
1117         }
1118         spin_unlock_irqrestore (&dev->txq.lock, flags);
1119
1120         if (retval) {
1121                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1122 drop:
1123                 dev->net->stats.tx_dropped++;
1124                 if (skb)
1125                         dev_kfree_skb_any (skb);
1126                 usb_free_urb (urb);
1127         } else
1128                 netif_dbg(dev, tx_queued, dev->net,
1129                           "> tx, len %d, type 0x%x\n", length, skb->protocol);
1130 #ifdef CONFIG_PM
1131 deferred:
1132 #endif
1133         return NETDEV_TX_OK;
1134 }
1135 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1136
1137 /*-------------------------------------------------------------------------*/
1138
1139 // tasklet (work deferred from completions, in_irq) or timer
1140
1141 static void usbnet_bh (unsigned long param)
1142 {
1143         struct usbnet           *dev = (struct usbnet *) param;
1144         struct sk_buff          *skb;
1145         struct skb_data         *entry;
1146
1147         while ((skb = skb_dequeue (&dev->done))) {
1148                 entry = (struct skb_data *) skb->cb;
1149                 switch (entry->state) {
1150                 case rx_done:
1151                         entry->state = rx_cleanup;
1152                         rx_process (dev, skb);
1153                         continue;
1154                 case tx_done:
1155                 case rx_cleanup:
1156                         usb_free_urb (entry->urb);
1157                         dev_kfree_skb (skb);
1158                         continue;
1159                 default:
1160                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1161                 }
1162         }
1163
1164         // waiting for all pending urbs to complete?
1165         if (dev->wait) {
1166                 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1167                         wake_up (dev->wait);
1168                 }
1169
1170         // or are we maybe short a few urbs?
1171         } else if (netif_running (dev->net) &&
1172                    netif_device_present (dev->net) &&
1173                    !timer_pending (&dev->delay) &&
1174                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1175                 int     temp = dev->rxq.qlen;
1176                 int     qlen = RX_QLEN (dev);
1177
1178                 if (temp < qlen) {
1179                         struct urb      *urb;
1180                         int             i;
1181
1182                         // don't refill the queue all at once
1183                         for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1184                                 urb = usb_alloc_urb (0, GFP_ATOMIC);
1185                                 if (urb != NULL) {
1186                                         if (rx_submit (dev, urb, GFP_ATOMIC) ==
1187                                             -ENOLINK)
1188                                                 return;
1189                                 }
1190                         }
1191                         if (temp != dev->rxq.qlen)
1192                                 netif_dbg(dev, link, dev->net,
1193                                           "rxqlen %d --> %d\n",
1194                                           temp, dev->rxq.qlen);
1195                         if (dev->rxq.qlen < qlen)
1196                                 tasklet_schedule (&dev->bh);
1197                 }
1198                 if (dev->txq.qlen < TX_QLEN (dev))
1199                         netif_wake_queue (dev->net);
1200         }
1201 }
1202
1203
1204 /*-------------------------------------------------------------------------
1205  *
1206  * USB Device Driver support
1207  *
1208  *-------------------------------------------------------------------------*/
1209
1210 // precondition: never called in_interrupt
1211
1212 void usbnet_disconnect (struct usb_interface *intf)
1213 {
1214         struct usbnet           *dev;
1215         struct usb_device       *xdev;
1216         struct net_device       *net;
1217
1218         dev = usb_get_intfdata(intf);
1219         usb_set_intfdata(intf, NULL);
1220         if (!dev)
1221                 return;
1222
1223         xdev = interface_to_usbdev (intf);
1224
1225         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1226                    intf->dev.driver->name,
1227                    xdev->bus->bus_name, xdev->devpath,
1228                    dev->driver_info->description);
1229
1230         net = dev->net;
1231         unregister_netdev (net);
1232
1233         /* we don't hold rtnl here ... */
1234         flush_scheduled_work ();
1235
1236         if (dev->driver_info->unbind)
1237                 dev->driver_info->unbind (dev, intf);
1238
1239         free_netdev(net);
1240         usb_put_dev (xdev);
1241 }
1242 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1243
1244 static const struct net_device_ops usbnet_netdev_ops = {
1245         .ndo_open               = usbnet_open,
1246         .ndo_stop               = usbnet_stop,
1247         .ndo_start_xmit         = usbnet_start_xmit,
1248         .ndo_tx_timeout         = usbnet_tx_timeout,
1249         .ndo_change_mtu         = usbnet_change_mtu,
1250         .ndo_set_mac_address    = eth_mac_addr,
1251         .ndo_validate_addr      = eth_validate_addr,
1252 };
1253
1254 /*-------------------------------------------------------------------------*/
1255
1256 // precondition: never called in_interrupt
1257
1258 static struct device_type wlan_type = {
1259         .name   = "wlan",
1260 };
1261
1262 static struct device_type wwan_type = {
1263         .name   = "wwan",
1264 };
1265
1266 int
1267 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1268 {
1269         struct usbnet                   *dev;
1270         struct net_device               *net;
1271         struct usb_host_interface       *interface;
1272         struct driver_info              *info;
1273         struct usb_device               *xdev;
1274         int                             status;
1275         const char                      *name;
1276
1277         name = udev->dev.driver->name;
1278         info = (struct driver_info *) prod->driver_info;
1279         if (!info) {
1280                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1281                 return -ENODEV;
1282         }
1283         xdev = interface_to_usbdev (udev);
1284         interface = udev->cur_altsetting;
1285
1286         usb_get_dev (xdev);
1287
1288         status = -ENOMEM;
1289
1290         // set up our own records
1291         net = alloc_etherdev(sizeof(*dev));
1292         if (!net) {
1293                 dbg ("can't kmalloc dev");
1294                 goto out;
1295         }
1296
1297         /* netdev_printk() needs this so do it as early as possible */
1298         SET_NETDEV_DEV(net, &udev->dev);
1299
1300         dev = netdev_priv(net);
1301         dev->udev = xdev;
1302         dev->intf = udev;
1303         dev->driver_info = info;
1304         dev->driver_name = name;
1305         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1306                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1307         skb_queue_head_init (&dev->rxq);
1308         skb_queue_head_init (&dev->txq);
1309         skb_queue_head_init (&dev->done);
1310         skb_queue_head_init(&dev->rxq_pause);
1311         dev->bh.func = usbnet_bh;
1312         dev->bh.data = (unsigned long) dev;
1313         INIT_WORK (&dev->kevent, kevent);
1314         init_usb_anchor(&dev->deferred);
1315         dev->delay.function = usbnet_bh;
1316         dev->delay.data = (unsigned long) dev;
1317         init_timer (&dev->delay);
1318         mutex_init (&dev->phy_mutex);
1319
1320         dev->net = net;
1321         strcpy (net->name, "usb%d");
1322         memcpy (net->dev_addr, node_id, sizeof node_id);
1323
1324         /* rx and tx sides can use different message sizes;
1325          * bind() should set rx_urb_size in that case.
1326          */
1327         dev->hard_mtu = net->mtu + net->hard_header_len;
1328 #if 0
1329 // dma_supported() is deeply broken on almost all architectures
1330         // possible with some EHCI controllers
1331         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1332                 net->features |= NETIF_F_HIGHDMA;
1333 #endif
1334
1335         net->netdev_ops = &usbnet_netdev_ops;
1336         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1337         net->ethtool_ops = &usbnet_ethtool_ops;
1338
1339         // allow device-specific bind/init procedures
1340         // NOTE net->name still not usable ...
1341         if (info->bind) {
1342                 status = info->bind (dev, udev);
1343                 if (status < 0)
1344                         goto out1;
1345
1346                 // heuristic:  "usb%d" for links we know are two-host,
1347                 // else "eth%d" when there's reasonable doubt.  userspace
1348                 // can rename the link if it knows better.
1349                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1350                     (net->dev_addr [0] & 0x02) == 0)
1351                         strcpy (net->name, "eth%d");
1352                 /* WLAN devices should always be named "wlan%d" */
1353                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1354                         strcpy(net->name, "wlan%d");
1355                 /* WWAN devices should always be named "wwan%d" */
1356                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1357                         strcpy(net->name, "wwan%d");
1358
1359                 /* maybe the remote can't receive an Ethernet MTU */
1360                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1361                         net->mtu = dev->hard_mtu - net->hard_header_len;
1362         } else if (!info->in || !info->out)
1363                 status = usbnet_get_endpoints (dev, udev);
1364         else {
1365                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1366                 dev->out = usb_sndbulkpipe (xdev, info->out);
1367                 if (!(info->flags & FLAG_NO_SETINT))
1368                         status = usb_set_interface (xdev,
1369                                 interface->desc.bInterfaceNumber,
1370                                 interface->desc.bAlternateSetting);
1371                 else
1372                         status = 0;
1373
1374         }
1375         if (status >= 0 && dev->status)
1376                 status = init_status (dev, udev);
1377         if (status < 0)
1378                 goto out3;
1379
1380         if (!dev->rx_urb_size)
1381                 dev->rx_urb_size = dev->hard_mtu;
1382         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1383
1384         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1385                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1386         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1387                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1388
1389         status = register_netdev (net);
1390         if (status)
1391                 goto out3;
1392         netif_info(dev, probe, dev->net,
1393                    "register '%s' at usb-%s-%s, %s, %pM\n",
1394                    udev->dev.driver->name,
1395                    xdev->bus->bus_name, xdev->devpath,
1396                    dev->driver_info->description,
1397                    net->dev_addr);
1398
1399         // ok, it's ready to go.
1400         usb_set_intfdata (udev, dev);
1401
1402         netif_device_attach (net);
1403
1404         if (dev->driver_info->flags & FLAG_LINK_INTR)
1405                 netif_carrier_off(net);
1406
1407         return 0;
1408
1409 out3:
1410         if (info->unbind)
1411                 info->unbind (dev, udev);
1412 out1:
1413         free_netdev(net);
1414 out:
1415         usb_put_dev(xdev);
1416         return status;
1417 }
1418 EXPORT_SYMBOL_GPL(usbnet_probe);
1419
1420 /*-------------------------------------------------------------------------*/
1421
1422 /*
1423  * suspend the whole driver as soon as the first interface is suspended
1424  * resume only when the last interface is resumed
1425  */
1426
1427 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1428 {
1429         struct usbnet           *dev = usb_get_intfdata(intf);
1430
1431         if (!dev->suspend_count++) {
1432                 spin_lock_irq(&dev->txq.lock);
1433                 /* don't autosuspend while transmitting */
1434                 if (dev->txq.qlen && (message.event & PM_EVENT_AUTO)) {
1435                         spin_unlock_irq(&dev->txq.lock);
1436                         return -EBUSY;
1437                 } else {
1438                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1439                         spin_unlock_irq(&dev->txq.lock);
1440                 }
1441                 /*
1442                  * accelerate emptying of the rx and queues, to avoid
1443                  * having everything error out.
1444                  */
1445                 netif_device_detach (dev->net);
1446                 usbnet_terminate_urbs(dev);
1447                 usb_kill_urb(dev->interrupt);
1448
1449                 /*
1450                  * reattach so runtime management can use and
1451                  * wake the device
1452                  */
1453                 netif_device_attach (dev->net);
1454         }
1455         return 0;
1456 }
1457 EXPORT_SYMBOL_GPL(usbnet_suspend);
1458
1459 int usbnet_resume (struct usb_interface *intf)
1460 {
1461         struct usbnet           *dev = usb_get_intfdata(intf);
1462         struct sk_buff          *skb;
1463         struct urb              *res;
1464         int                     retval;
1465
1466         if (!--dev->suspend_count) {
1467                 spin_lock_irq(&dev->txq.lock);
1468                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1469
1470                         skb = (struct sk_buff *)res->context;
1471                         retval = usb_submit_urb(res, GFP_ATOMIC);
1472                         if (retval < 0) {
1473                                 dev_kfree_skb_any(skb);
1474                                 usb_free_urb(res);
1475                                 usb_autopm_put_interface_async(dev->intf);
1476                         } else {
1477                                 dev->net->trans_start = jiffies;
1478                                 __skb_queue_tail(&dev->txq, skb);
1479                         }
1480                 }
1481
1482                 smp_mb();
1483                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1484                 spin_unlock_irq(&dev->txq.lock);
1485                 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1486                         netif_start_queue(dev->net);
1487                 tasklet_schedule (&dev->bh);
1488         }
1489         return 0;
1490 }
1491 EXPORT_SYMBOL_GPL(usbnet_resume);
1492
1493
1494 /*-------------------------------------------------------------------------*/
1495
1496 static int __init usbnet_init(void)
1497 {
1498         /* compiler should optimize this out */
1499         BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1500                         < sizeof (struct skb_data));
1501
1502         random_ether_addr(node_id);
1503         return 0;
1504 }
1505 module_init(usbnet_init);
1506
1507 static void __exit usbnet_exit(void)
1508 {
1509 }
1510 module_exit(usbnet_exit);
1511
1512 MODULE_AUTHOR("David Brownell");
1513 MODULE_DESCRIPTION("USB network driver framework");
1514 MODULE_LICENSE("GPL");