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 #include <linux/pm_runtime.h>
  49
  50 #define DRIVER_VERSION          "22-Aug-2005"
  51
  52
  53 /*-------------------------------------------------------------------------*/
  54
  55 /*
  56  * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  57  * Several dozen bytes of IPv4 data can fit in two such transactions.
  58  * One maximum size Ethernet packet takes twenty four of them.
  59  * For high speed, each frame comfortably fits almost 36 max size
  60  * Ethernet packets (so queues should be bigger).
  61  *
  62  * REVISIT qlens should be members of 'struct usbnet'; the goal is to
  63  * let the USB host controller be busy for 5msec or more before an irq
  64  * is required, under load.  Jumbograms change the equation.
  65  */
  66 #define RX_MAX_QUEUE_MEMORY (60 * 1518)
  67 #define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  68                         (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
  69 #define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  70                         (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
  71
  72 // reawaken network queue this soon after stopping; else watchdog barks
  73 #define TX_TIMEOUT_JIFFIES      (5*HZ)
  74
  75 // throttle rx/tx briefly after some faults, so khubd might disconnect()
  76 // us (it polls at HZ/4 usually) before we report too many false errors.
  77 #define THROTTLE_JIFFIES        (HZ/8)
  78
  79 // between wakeups
  80 #define UNLINK_TIMEOUT_MS       3
  81
  82 /*-------------------------------------------------------------------------*/
  83
  84 // randomly generated ethernet address
  85 static u8       node_id [ETH_ALEN];
  86
  87 static const char driver_name [] = "usbnet";
  88
  89 /* use ethtool to change the level for any given device */
  90 static int msg_level = -1;
  91 module_param (msg_level, int, 0);
  92 MODULE_PARM_DESC (msg_level, "Override default message level");
  93
  94 /*-------------------------------------------------------------------------*/
  95
  96 /* handles CDC Ethernet and many other network "bulk data" interfaces */
  97 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  98 {
  99         int                             tmp;
 100         struct usb_host_interface       *alt = NULL;
 101         struct usb_host_endpoint        *in = NULL, *out = NULL;
 102         struct usb_host_endpoint        *status = NULL;
 103
 104         for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 105                 unsigned        ep;
 106
 107                 in = out = status = NULL;
 108                 alt = intf->altsetting + tmp;
 109
 110                 /* take the first altsetting with in-bulk + out-bulk;
 111                  * remember any status endpoint, just in case;
 112                  * ignore other endpoints and altsetttings.
 113                  */
 114                 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 115                         struct usb_host_endpoint        *e;
 116                         int                             intr = 0;
 117
 118                         e = alt->endpoint + ep;
 119                         switch (e->desc.bmAttributes) {
 120                         case USB_ENDPOINT_XFER_INT:
 121                                 if (!usb_endpoint_dir_in(&e->desc))
 122                                         continue;
 123                                 intr = 1;
 124                                 /* FALLTHROUGH */
 125                         case USB_ENDPOINT_XFER_BULK:
 126                                 break;
 127                         default:
 128                                 continue;
 129                         }
 130                         if (usb_endpoint_dir_in(&e->desc)) {
 131                                 if (!intr && !in)
 132                                         in = e;
 133                                 else if (intr && !status)
 134                                         status = e;
 135                         } else {
 136                                 if (!out)
 137                                         out = e;
 138                         }
 139                 }
 140                 if (in && out)
 141                         break;
 142         }
 143         if (!alt || !in || !out)
 144                 return -EINVAL;
 145
 146         if (alt->desc.bAlternateSetting != 0 ||
 147             !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 148                 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 149                                 alt->desc.bAlternateSetting);
 150                 if (tmp < 0)
 151                         return tmp;
 152         }
 153
 154         dev->in = usb_rcvbulkpipe (dev->udev,
 155                         in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 156         dev->out = usb_sndbulkpipe (dev->udev,
 157                         out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 158         dev->status = status;
 159         return 0;
 160 }
 161 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 162
 163 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 164 {
 165         int             tmp, i;
 166         unsigned char   buf [13];
 167
 168         tmp = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 169         if (tmp != 12) {
 170                 dev_dbg(&dev->udev->dev,
 171                         "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 172                 if (tmp >= 0)
 173                         tmp = -EINVAL;
 174                 return tmp;
 175         }
 176         for (i = tmp = 0; i < 6; i++, tmp += 2)
 177                 dev->net->dev_addr [i] =
 178                         (hex_to_bin(buf[tmp]) << 4) + hex_to_bin(buf[tmp + 1]);
 179         return 0;
 180 }
 181 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 182
 183 static void intr_complete (struct urb *urb);
 184
 185 static int init_status (struct usbnet *dev, struct usb_interface *intf)
 186 {
 187         char            *buf = NULL;
 188         unsigned        pipe = 0;
 189         unsigned        maxp;
 190         unsigned        period;
 191
 192         if (!dev->driver_info->status)
 193                 return 0;
 194
 195         pipe = usb_rcvintpipe (dev->udev,
 196                         dev->status->desc.bEndpointAddress
 197                                 & USB_ENDPOINT_NUMBER_MASK);
 198         maxp = usb_maxpacket (dev->udev, pipe, 0);
 199
 200         /* avoid 1 msec chatter:  min 8 msec poll rate */
 201         period = max ((int) dev->status->desc.bInterval,
 202                 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 203
 204         buf = kmalloc (maxp, GFP_KERNEL);
 205         if (buf) {
 206                 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 207                 if (!dev->interrupt) {
 208                         kfree (buf);
 209                         return -ENOMEM;
 210                 } else {
 211                         usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 212                                 buf, maxp, intr_complete, dev, period);
 213                         dev_dbg(&intf->dev,
 214                                 "status ep%din, %d bytes period %d\n",
 215                                 usb_pipeendpoint(pipe), maxp, period);
 216                 }
 217         }
 218         return 0;
 219 }
 220
 221 /* Passes this packet up the stack, updating its accounting.
 222  * Some link protocols batch packets, so their rx_fixup paths
 223  * can return clones as well as just modify the original skb.
 224  */
 225 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 226 {
 227         int     status;
 228
 229         if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 230                 skb_queue_tail(&dev->rxq_pause, skb);
 231                 return;
 232         }
 233
 234         skb->protocol = eth_type_trans (skb, dev->net);
 235         dev->net->stats.rx_packets++;
 236         dev->net->stats.rx_bytes += skb->len;
 237
 238         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 239                   skb->len + sizeof (struct ethhdr), skb->protocol);
 240         memset (skb->cb, 0, sizeof (struct skb_data));
 241         status = netif_rx (skb);
 242         if (status != NET_RX_SUCCESS)
 243                 netif_dbg(dev, rx_err, dev->net,
 244                           "netif_rx status %d\n", status);
 245 }
 246 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 247
 248 \f
 249 /*-------------------------------------------------------------------------
 250  *
 251  * Network Device Driver (peer link to "Host Device", from USB host)
 252  *
 253  *-------------------------------------------------------------------------*/
 254
 255 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 256 {
 257         struct usbnet   *dev = netdev_priv(net);
 258         int             ll_mtu = new_mtu + net->hard_header_len;
 259         int             old_hard_mtu = dev->hard_mtu;
 260         int             old_rx_urb_size = dev->rx_urb_size;
 261
 262         if (new_mtu <= 0)
 263                 return -EINVAL;
 264         // no second zero-length packet read wanted after mtu-sized packets
 265         if ((ll_mtu % dev->maxpacket) == 0)
 266                 return -EDOM;
 267         net->mtu = new_mtu;
 268
 269         dev->hard_mtu = net->mtu + net->hard_header_len;
 270         if (dev->rx_urb_size == old_hard_mtu) {
 271                 dev->rx_urb_size = dev->hard_mtu;
 272                 if (dev->rx_urb_size > old_rx_urb_size)
 273                         usbnet_unlink_rx_urbs(dev);
 274         }
 275
 276         return 0;
 277 }
 278 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 279
 280 /*-------------------------------------------------------------------------*/
 281
 282 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 283  * completion callbacks.  2.5 should have fixed those bugs...
 284  */
 285
 286 static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 287 {
 288         unsigned long           flags;
 289
 290         spin_lock_irqsave(&list->lock, flags);
 291         __skb_unlink(skb, list);
 292         spin_unlock(&list->lock);
 293         spin_lock(&dev->done.lock);
 294         __skb_queue_tail(&dev->done, skb);
 295         if (dev->done.qlen == 1)
 296                 tasklet_schedule(&dev->bh);
 297         spin_unlock_irqrestore(&dev->done.lock, flags);
 298 }
 299
 300 /* some work can't be done in tasklets, so we use keventd
 301  *
 302  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 303  * but tasklet_schedule() doesn't.  hope the failure is rare.
 304  */
 305 void usbnet_defer_kevent (struct usbnet *dev, int work)
 306 {
 307         set_bit (work, &dev->flags);
 308         if (!schedule_work (&dev->kevent))
 309                 netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 310         else
 311                 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 312 }
 313 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 314
 315 /*-------------------------------------------------------------------------*/
 316
 317 static void rx_complete (struct urb *urb);
 318
 319 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 320 {
 321         struct sk_buff          *skb;
 322         struct skb_data         *entry;
 323         int                     retval = 0;
 324         unsigned long           lockflags;
 325         size_t                  size = dev->rx_urb_size;
 326
 327         if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
 328                 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 329                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 330                 usb_free_urb (urb);
 331                 return -ENOMEM;
 332         }
 333         skb_reserve (skb, NET_IP_ALIGN);
 334
 335         entry = (struct skb_data *) skb->cb;
 336         entry->urb = urb;
 337         entry->dev = dev;
 338         entry->state = rx_start;
 339         entry->length = 0;
 340
 341         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 342                 skb->data, size, rx_complete, skb);
 343
 344         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 345
 346         if (netif_running (dev->net) &&
 347             netif_device_present (dev->net) &&
 348             !test_bit (EVENT_RX_HALT, &dev->flags) &&
 349             !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 350                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 351                 case -EPIPE:
 352                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 353                         break;
 354                 case -ENOMEM:
 355                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 356                         break;
 357                 case -ENODEV:
 358                         netif_dbg(dev, ifdown, dev->net, "device gone\n");
 359                         netif_device_detach (dev->net);
 360                         break;
 361                 case -EHOSTUNREACH:
 362                         retval = -ENOLINK;
 363                         break;
 364                 default:
 365                         netif_dbg(dev, rx_err, dev->net,
 366                                   "rx submit, %d\n", retval);
 367                         tasklet_schedule (&dev->bh);
 368                         break;
 369                 case 0:
 370                         __skb_queue_tail (&dev->rxq, skb);
 371                 }
 372         } else {
 373                 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 374                 retval = -ENOLINK;
 375         }
 376         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 377         if (retval) {
 378                 dev_kfree_skb_any (skb);
 379                 usb_free_urb (urb);
 380         }
 381         return retval;
 382 }
 383
 384
 385 /*-------------------------------------------------------------------------*/
 386
 387 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 388 {
 389         if (dev->driver_info->rx_fixup &&
 390             !dev->driver_info->rx_fixup (dev, skb)) {
 391                 /* With RX_ASSEMBLE, rx_fixup() must update counters */
 392                 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
 393                         dev->net->stats.rx_errors++;
 394                 goto done;
 395         }
 396         // else network stack removes extra byte if we forced a short packet
 397
 398         if (skb->len) {
 399                 /* all data was already cloned from skb inside the driver */
 400                 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
 401                         dev_kfree_skb_any(skb);
 402                 else
 403                         usbnet_skb_return(dev, skb);
 404                 return;
 405         }
 406
 407         netif_dbg(dev, rx_err, dev->net, "drop\n");
 408         dev->net->stats.rx_errors++;
 409 done:
 410         skb_queue_tail(&dev->done, skb);
 411 }
 412
 413 /*-------------------------------------------------------------------------*/
 414
 415 static void rx_complete (struct urb *urb)
 416 {
 417         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 418         struct skb_data         *entry = (struct skb_data *) skb->cb;
 419         struct usbnet           *dev = entry->dev;
 420         int                     urb_status = urb->status;
 421
 422         skb_put (skb, urb->actual_length);
 423         entry->state = rx_done;
 424         entry->urb = NULL;
 425
 426         switch (urb_status) {
 427         /* success */
 428         case 0:
 429                 if (skb->len < dev->net->hard_header_len) {
 430                         entry->state = rx_cleanup;
 431                         dev->net->stats.rx_errors++;
 432                         dev->net->stats.rx_length_errors++;
 433                         netif_dbg(dev, rx_err, dev->net,
 434                                   "rx length %d\n", skb->len);
 435                 }
 436                 break;
 437
 438         /* stalls need manual reset. this is rare ... except that
 439          * when going through USB 2.0 TTs, unplug appears this way.
 440          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 441          * storm, recovering as needed.
 442          */
 443         case -EPIPE:
 444                 dev->net->stats.rx_errors++;
 445                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 446                 // FALLTHROUGH
 447
 448         /* software-driven interface shutdown */
 449         case -ECONNRESET:               /* async unlink */
 450         case -ESHUTDOWN:                /* hardware gone */
 451                 netif_dbg(dev, ifdown, dev->net,
 452                           "rx shutdown, code %d\n", urb_status);
 453                 goto block;
 454
 455         /* we get controller i/o faults during khubd disconnect() delays.
 456          * throttle down resubmits, to avoid log floods; just temporarily,
 457          * so we still recover when the fault isn't a khubd delay.
 458          */
 459         case -EPROTO:
 460         case -ETIME:
 461         case -EILSEQ:
 462                 dev->net->stats.rx_errors++;
 463                 if (!timer_pending (&dev->delay)) {
 464                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 465                         netif_dbg(dev, link, dev->net,
 466                                   "rx throttle %d\n", urb_status);
 467                 }
 468 block:
 469                 entry->state = rx_cleanup;
 470                 entry->urb = urb;
 471                 urb = NULL;
 472                 break;
 473
 474         /* data overrun ... flush fifo? */
 475         case -EOVERFLOW:
 476                 dev->net->stats.rx_over_errors++;
 477                 // FALLTHROUGH
 478
 479         default:
 480                 entry->state = rx_cleanup;
 481                 dev->net->stats.rx_errors++;
 482                 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 483                 break;
 484         }
 485
 486         defer_bh(dev, skb, &dev->rxq);
 487
 488         if (urb) {
 489                 if (netif_running (dev->net) &&
 490                     !test_bit (EVENT_RX_HALT, &dev->flags)) {
 491                         rx_submit (dev, urb, GFP_ATOMIC);
 492                         return;
 493                 }
 494                 usb_free_urb (urb);
 495         }
 496         netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 497 }
 498
 499 static void intr_complete (struct urb *urb)
 500 {
 501         struct usbnet   *dev = urb->context;
 502         int             status = urb->status;
 503
 504         switch (status) {
 505         /* success */
 506         case 0:
 507                 dev->driver_info->status(dev, urb);
 508                 break;
 509
 510         /* software-driven interface shutdown */
 511         case -ENOENT:           /* urb killed */
 512         case -ESHUTDOWN:        /* hardware gone */
 513                 netif_dbg(dev, ifdown, dev->net,
 514                           "intr shutdown, code %d\n", status);
 515                 return;
 516
 517         /* NOTE:  not throttling like RX/TX, since this endpoint
 518          * already polls infrequently
 519          */
 520         default:
 521                 netdev_dbg(dev->net, "intr status %d\n", status);
 522                 break;
 523         }
 524
 525         if (!netif_running (dev->net))
 526                 return;
 527
 528         memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 529         status = usb_submit_urb (urb, GFP_ATOMIC);
 530         if (status != 0)
 531                 netif_err(dev, timer, dev->net,
 532                           "intr resubmit --> %d\n", status);
 533 }
 534
 535 /*-------------------------------------------------------------------------*/
 536 void usbnet_pause_rx(struct usbnet *dev)
 537 {
 538         set_bit(EVENT_RX_PAUSED, &dev->flags);
 539
 540         netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 541 }
 542 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 543
 544 void usbnet_resume_rx(struct usbnet *dev)
 545 {
 546         struct sk_buff *skb;
 547         int num = 0;
 548
 549         clear_bit(EVENT_RX_PAUSED, &dev->flags);
 550
 551         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 552                 usbnet_skb_return(dev, skb);
 553                 num++;
 554         }
 555
 556         tasklet_schedule(&dev->bh);
 557
 558         netif_dbg(dev, rx_status, dev->net,
 559                   "paused rx queue disabled, %d skbs requeued\n", num);
 560 }
 561 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 562
 563 void usbnet_purge_paused_rxq(struct usbnet *dev)
 564 {
 565         skb_queue_purge(&dev->rxq_pause);
 566 }
 567 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 568
 569 /*-------------------------------------------------------------------------*/
 570
 571 // unlink pending rx/tx; completion handlers do all other cleanup
 572
 573 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 574 {
 575         unsigned long           flags;
 576         struct sk_buff          *skb, *skbnext;
 577         int                     count = 0;
 578
 579         spin_lock_irqsave (&q->lock, flags);
 580         skb_queue_walk_safe(q, skb, skbnext) {
 581                 struct skb_data         *entry;
 582                 struct urb              *urb;
 583                 int                     retval;
 584
 585                 entry = (struct skb_data *) skb->cb;
 586                 urb = entry->urb;
 587
 588                 // during some PM-driven resume scenarios,
 589                 // these (async) unlinks complete immediately
 590                 retval = usb_unlink_urb (urb);
 591                 if (retval != -EINPROGRESS && retval != 0)
 592                         netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 593                 else
 594                         count++;
 595         }
 596         spin_unlock_irqrestore (&q->lock, flags);
 597         return count;
 598 }
 599
 600 // Flush all pending rx urbs
 601 // minidrivers may need to do this when the MTU changes
 602
 603 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 604 {
 605         if (netif_running(dev->net)) {
 606                 (void) unlink_urbs (dev, &dev->rxq);
 607                 tasklet_schedule(&dev->bh);
 608         }
 609 }
 610 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 611
 612 /*-------------------------------------------------------------------------*/
 613
 614 // precondition: never called in_interrupt
 615 static void usbnet_terminate_urbs(struct usbnet *dev)
 616 {
 617         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(unlink_wakeup);
 618         DECLARE_WAITQUEUE(wait, current);
 619         int temp;
 620
 621         /* ensure there are no more active urbs */
 622         add_wait_queue(&unlink_wakeup, &wait);
 623         set_current_state(TASK_UNINTERRUPTIBLE);
 624         dev->wait = &unlink_wakeup;
 625         temp = unlink_urbs(dev, &dev->txq) +
 626                 unlink_urbs(dev, &dev->rxq);
 627
 628         /* maybe wait for deletions to finish. */
 629         while (!skb_queue_empty(&dev->rxq)
 630                 && !skb_queue_empty(&dev->txq)
 631                 && !skb_queue_empty(&dev->done)) {
 632                         schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 633                         set_current_state(TASK_UNINTERRUPTIBLE);
 634                         netif_dbg(dev, ifdown, dev->net,
 635                                   "waited for %d urb completions\n", temp);
 636         }
 637         set_current_state(TASK_RUNNING);
 638         dev->wait = NULL;
 639         remove_wait_queue(&unlink_wakeup, &wait);
 640 }
 641
 642 int usbnet_stop (struct net_device *net)
 643 {
 644         struct usbnet           *dev = netdev_priv(net);
 645         struct driver_info      *info = dev->driver_info;
 646         int                     retval;
 647
 648         netif_stop_queue (net);
 649
 650         netif_info(dev, ifdown, dev->net,
 651                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 652                    net->stats.rx_packets, net->stats.tx_packets,
 653                    net->stats.rx_errors, net->stats.tx_errors);
 654
 655         /* allow minidriver to stop correctly (wireless devices to turn off
 656          * radio etc) */
 657         if (info->stop) {
 658                 retval = info->stop(dev);
 659                 if (retval < 0)
 660                         netif_info(dev, ifdown, dev->net,
 661                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
 662                                    retval,
 663                                    dev->udev->bus->bus_name, dev->udev->devpath,
 664                                    info->description);
 665         }
 666
 667         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 668                 usbnet_terminate_urbs(dev);
 669
 670         usb_kill_urb(dev->interrupt);
 671
 672         usbnet_purge_paused_rxq(dev);
 673
 674         /* deferred work (task, timer, softirq) must also stop.
 675          * can't flush_scheduled_work() until we drop rtnl (later),
 676          * else workers could deadlock; so make workers a NOP.
 677          */
 678         dev->flags = 0;
 679         del_timer_sync (&dev->delay);
 680         tasklet_kill (&dev->bh);
 681         if (info->manage_power)
 682                 info->manage_power(dev, 0);
 683         else
 684                 usb_autopm_put_interface(dev->intf);
 685
 686         return 0;
 687 }
 688 EXPORT_SYMBOL_GPL(usbnet_stop);
 689
 690 /*-------------------------------------------------------------------------*/
 691
 692 // posts reads, and enables write queuing
 693
 694 // precondition: never called in_interrupt
 695
 696 int usbnet_open (struct net_device *net)
 697 {
 698         struct usbnet           *dev = netdev_priv(net);
 699         int                     retval;
 700         struct driver_info      *info = dev->driver_info;
 701
 702         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 703                 netif_info(dev, ifup, dev->net,
 704                            "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 705                            retval,
 706                            dev->udev->bus->bus_name,
 707                            dev->udev->devpath,
 708                            info->description);
 709                 goto done_nopm;
 710         }
 711
 712         // put into "known safe" state
 713         if (info->reset && (retval = info->reset (dev)) < 0) {
 714                 netif_info(dev, ifup, dev->net,
 715                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 716                            retval,
 717                            dev->udev->bus->bus_name,
 718                            dev->udev->devpath,
 719                            info->description);
 720                 goto done;
 721         }
 722
 723         // insist peer be connected
 724         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 725                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 726                 goto done;
 727         }
 728
 729         /* start any status interrupt transfer */
 730         if (dev->interrupt) {
 731                 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 732                 if (retval < 0) {
 733                         netif_err(dev, ifup, dev->net,
 734                                   "intr submit %d\n", retval);
 735                         goto done;
 736                 }
 737         }
 738
 739         netif_start_queue (net);
 740         netif_info(dev, ifup, dev->net,
 741                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 742                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 743                    dev->net->mtu,
 744                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 745                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 746                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 747                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 748                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 749                    "simple");
 750
 751         // delay posting reads until we're fully open
 752         tasklet_schedule (&dev->bh);
 753         if (info->manage_power) {
 754                 retval = info->manage_power(dev, 1);
 755                 if (retval < 0)
 756                         goto done;
 757                 usb_autopm_put_interface(dev->intf);
 758         }
 759         return retval;
 760
 761 done:
 762         usb_autopm_put_interface(dev->intf);
 763 done_nopm:
 764         return retval;
 765 }
 766 EXPORT_SYMBOL_GPL(usbnet_open);
 767
 768 /*-------------------------------------------------------------------------*/
 769
 770 /* ethtool methods; minidrivers may need to add some more, but
 771  * they'll probably want to use this base set.
 772  */
 773
 774 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 775 {
 776         struct usbnet *dev = netdev_priv(net);
 777
 778         if (!dev->mii.mdio_read)
 779                 return -EOPNOTSUPP;
 780
 781         return mii_ethtool_gset(&dev->mii, cmd);
 782 }
 783 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 784
 785 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 786 {
 787         struct usbnet *dev = netdev_priv(net);
 788         int retval;
 789
 790         if (!dev->mii.mdio_write)
 791                 return -EOPNOTSUPP;
 792
 793         retval = mii_ethtool_sset(&dev->mii, cmd);
 794
 795         /* link speed/duplex might have changed */
 796         if (dev->driver_info->link_reset)
 797                 dev->driver_info->link_reset(dev);
 798
 799         return retval;
 800
 801 }
 802 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 803
 804 u32 usbnet_get_link (struct net_device *net)
 805 {
 806         struct usbnet *dev = netdev_priv(net);
 807
 808         /* If a check_connect is defined, return its result */
 809         if (dev->driver_info->check_connect)
 810                 return dev->driver_info->check_connect (dev) == 0;
 811
 812         /* if the device has mii operations, use those */
 813         if (dev->mii.mdio_read)
 814                 return mii_link_ok(&dev->mii);
 815
 816         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 817         return ethtool_op_get_link(net);
 818 }
 819 EXPORT_SYMBOL_GPL(usbnet_get_link);
 820
 821 int usbnet_nway_reset(struct net_device *net)
 822 {
 823         struct usbnet *dev = netdev_priv(net);
 824
 825         if (!dev->mii.mdio_write)
 826                 return -EOPNOTSUPP;
 827
 828         return mii_nway_restart(&dev->mii);
 829 }
 830 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 831
 832 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 833 {
 834         struct usbnet *dev = netdev_priv(net);
 835
 836         strncpy (info->driver, dev->driver_name, sizeof info->driver);
 837         strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 838         strncpy (info->fw_version, dev->driver_info->description,
 839                 sizeof info->fw_version);
 840         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 841 }
 842 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 843
 844 u32 usbnet_get_msglevel (struct net_device *net)
 845 {
 846         struct usbnet *dev = netdev_priv(net);
 847
 848         return dev->msg_enable;
 849 }
 850 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 851
 852 void usbnet_set_msglevel (struct net_device *net, u32 level)
 853 {
 854         struct usbnet *dev = netdev_priv(net);
 855
 856         dev->msg_enable = level;
 857 }
 858 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 859
 860 /* drivers may override default ethtool_ops in their bind() routine */
 861 static const struct ethtool_ops usbnet_ethtool_ops = {
 862         .get_settings           = usbnet_get_settings,
 863         .set_settings           = usbnet_set_settings,
 864         .get_link               = usbnet_get_link,
 865         .nway_reset             = usbnet_nway_reset,
 866         .get_drvinfo            = usbnet_get_drvinfo,
 867         .get_msglevel           = usbnet_get_msglevel,
 868         .set_msglevel           = usbnet_set_msglevel,
 869 };
 870
 871 /*-------------------------------------------------------------------------*/
 872
 873 /* work that cannot be done in interrupt context uses keventd.
 874  *
 875  * NOTE:  with 2.5 we could do more of this using completion callbacks,
 876  * especially now that control transfers can be queued.
 877  */
 878 static void
 879 kevent (struct work_struct *work)
 880 {
 881         struct usbnet           *dev =
 882                 container_of(work, struct usbnet, kevent);
 883         int                     status;
 884
 885         /* usb_clear_halt() needs a thread context */
 886         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 887                 unlink_urbs (dev, &dev->txq);
 888                 status = usb_autopm_get_interface(dev->intf);
 889                 if (status < 0)
 890                         goto fail_pipe;
 891                 status = usb_clear_halt (dev->udev, dev->out);
 892                 usb_autopm_put_interface(dev->intf);
 893                 if (status < 0 &&
 894                     status != -EPIPE &&
 895                     status != -ESHUTDOWN) {
 896                         if (netif_msg_tx_err (dev))
 897 fail_pipe:
 898                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
 899                                            status);
 900                 } else {
 901                         clear_bit (EVENT_TX_HALT, &dev->flags);
 902                         if (status != -ESHUTDOWN)
 903                                 netif_wake_queue (dev->net);
 904                 }
 905         }
 906         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 907                 unlink_urbs (dev, &dev->rxq);
 908                 status = usb_autopm_get_interface(dev->intf);
 909                 if (status < 0)
 910                         goto fail_halt;
 911                 status = usb_clear_halt (dev->udev, dev->in);
 912                 usb_autopm_put_interface(dev->intf);
 913                 if (status < 0 &&
 914                     status != -EPIPE &&
 915                     status != -ESHUTDOWN) {
 916                         if (netif_msg_rx_err (dev))
 917 fail_halt:
 918                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
 919                                            status);
 920                 } else {
 921                         clear_bit (EVENT_RX_HALT, &dev->flags);
 922                         tasklet_schedule (&dev->bh);
 923                 }
 924         }
 925
 926         /* tasklet could resubmit itself forever if memory is tight */
 927         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 928                 struct urb      *urb = NULL;
 929                 int resched = 1;
 930
 931                 if (netif_running (dev->net))
 932                         urb = usb_alloc_urb (0, GFP_KERNEL);
 933                 else
 934                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 935                 if (urb != NULL) {
 936                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 937                         status = usb_autopm_get_interface(dev->intf);
 938                         if (status < 0) {
 939                                 usb_free_urb(urb);
 940                                 goto fail_lowmem;
 941                         }
 942                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
 943                                 resched = 0;
 944                         usb_autopm_put_interface(dev->intf);
 945 fail_lowmem:
 946                         if (resched)
 947                                 tasklet_schedule (&dev->bh);
 948                 }
 949         }
 950
 951         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 952                 struct driver_info      *info = dev->driver_info;
 953                 int                     retval = 0;
 954
 955                 clear_bit (EVENT_LINK_RESET, &dev->flags);
 956                 status = usb_autopm_get_interface(dev->intf);
 957                 if (status < 0)
 958                         goto skip_reset;
 959                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 960                         usb_autopm_put_interface(dev->intf);
 961 skip_reset:
 962                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
 963                                     retval,
 964                                     dev->udev->bus->bus_name,
 965                                     dev->udev->devpath,
 966                                     info->description);
 967                 } else {
 968                         usb_autopm_put_interface(dev->intf);
 969                 }
 970         }
 971
 972         if (dev->flags)
 973                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
 974 }
 975
 976 /*-------------------------------------------------------------------------*/
 977
 978 static void tx_complete (struct urb *urb)
 979 {
 980         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 981         struct skb_data         *entry = (struct skb_data *) skb->cb;
 982         struct usbnet           *dev = entry->dev;
 983
 984         if (urb->status == 0) {
 985                 if (!(dev->driver_info->flags & FLAG_MULTI_PACKET))
 986                         dev->net->stats.tx_packets++;
 987                 dev->net->stats.tx_bytes += entry->length;
 988         } else {
 989                 dev->net->stats.tx_errors++;
 990
 991                 switch (urb->status) {
 992                 case -EPIPE:
 993                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
 994                         break;
 995
 996                 /* software-driven interface shutdown */
 997                 case -ECONNRESET:               // async unlink
 998                 case -ESHUTDOWN:                // hardware gone
 999                         break;
1000
1001                 // like rx, tx gets controller i/o faults during khubd delays
1002                 // and so it uses the same throttling mechanism.
1003                 case -EPROTO:
1004                 case -ETIME:
1005                 case -EILSEQ:
1006                         usb_mark_last_busy(dev->udev);
1007                         if (!timer_pending (&dev->delay)) {
1008                                 mod_timer (&dev->delay,
1009                                         jiffies + THROTTLE_JIFFIES);
1010                                 netif_dbg(dev, link, dev->net,
1011                                           "tx throttle %d\n", urb->status);
1012                         }
1013                         netif_stop_queue (dev->net);
1014                         break;
1015                 default:
1016                         netif_dbg(dev, tx_err, dev->net,
1017                                   "tx err %d\n", entry->urb->status);
1018                         break;
1019                 }
1020         }
1021
1022         usb_autopm_put_interface_async(dev->intf);
1023         urb->dev = NULL;
1024         entry->state = tx_done;
1025         defer_bh(dev, skb, &dev->txq);
1026 }
1027
1028 /*-------------------------------------------------------------------------*/
1029
1030 void usbnet_tx_timeout (struct net_device *net)
1031 {
1032         struct usbnet           *dev = netdev_priv(net);
1033
1034         unlink_urbs (dev, &dev->txq);
1035         tasklet_schedule (&dev->bh);
1036
1037         // FIXME: device recovery -- reset?
1038 }
1039 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1040
1041 /*-------------------------------------------------------------------------*/
1042
1043 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1044                                      struct net_device *net)
1045 {
1046         struct usbnet           *dev = netdev_priv(net);
1047         int                     length;
1048         struct urb              *urb = NULL;
1049         struct skb_data         *entry;
1050         struct driver_info      *info = dev->driver_info;
1051         unsigned long           flags;
1052         int retval;
1053
1054         // some devices want funky USB-level framing, for
1055         // win32 driver (usually) and/or hardware quirks
1056         if (info->tx_fixup) {
1057                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1058                 if (!skb) {
1059                         if (netif_msg_tx_err(dev)) {
1060                                 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1061                                 goto drop;
1062                         } else {
1063                                 /* cdc_ncm collected packet; waits for more */
1064                                 goto not_drop;
1065                         }
1066                 }
1067         }
1068         length = skb->len;
1069
1070         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1071                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1072                 goto drop;
1073         }
1074
1075         entry = (struct skb_data *) skb->cb;
1076         entry->urb = urb;
1077         entry->dev = dev;
1078         entry->state = tx_start;
1079         entry->length = length;
1080
1081         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1082                         skb->data, skb->len, tx_complete, skb);
1083
1084         /* don't assume the hardware handles USB_ZERO_PACKET
1085          * NOTE:  strictly conforming cdc-ether devices should expect
1086          * the ZLP here, but ignore the one-byte packet.
1087          * NOTE2: CDC NCM specification is different from CDC ECM when
1088          * handling ZLP/short packets, so cdc_ncm driver will make short
1089          * packet itself if needed.
1090          */
1091         if (length % dev->maxpacket == 0) {
1092                 if (!(info->flags & FLAG_SEND_ZLP)) {
1093                         if (!(info->flags & FLAG_MULTI_PACKET)) {
1094                                 urb->transfer_buffer_length++;
1095                                 if (skb_tailroom(skb)) {
1096                                         skb->data[skb->len] = 0;
1097                                         __skb_put(skb, 1);
1098                                 }
1099                         }
1100                 } else
1101                         urb->transfer_flags |= URB_ZERO_PACKET;
1102         }
1103
1104         spin_lock_irqsave(&dev->txq.lock, flags);
1105         retval = usb_autopm_get_interface_async(dev->intf);
1106         if (retval < 0) {
1107                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1108                 goto drop;
1109         }
1110
1111 #ifdef CONFIG_PM
1112         /* if this triggers the device is still a sleep */
1113         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1114                 /* transmission will be done in resume */
1115                 usb_anchor_urb(urb, &dev->deferred);
1116                 /* no use to process more packets */
1117                 netif_stop_queue(net);
1118                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1119                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1120                 goto deferred;
1121         }
1122 #endif
1123
1124         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1125         case -EPIPE:
1126                 netif_stop_queue (net);
1127                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1128                 usb_autopm_put_interface_async(dev->intf);
1129                 break;
1130         default:
1131                 usb_autopm_put_interface_async(dev->intf);
1132                 netif_dbg(dev, tx_err, dev->net,
1133                           "tx: submit urb err %d\n", retval);
1134                 break;
1135         case 0:
1136                 net->trans_start = jiffies;
1137                 __skb_queue_tail (&dev->txq, skb);
1138                 if (dev->txq.qlen >= TX_QLEN (dev))
1139                         netif_stop_queue (net);
1140         }
1141         spin_unlock_irqrestore (&dev->txq.lock, flags);
1142
1143         if (retval) {
1144                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1145 drop:
1146                 dev->net->stats.tx_dropped++;
1147 not_drop:
1148                 if (skb)
1149                         dev_kfree_skb_any (skb);
1150                 usb_free_urb (urb);
1151         } else
1152                 netif_dbg(dev, tx_queued, dev->net,
1153                           "> tx, len %d, type 0x%x\n", length, skb->protocol);
1154 #ifdef CONFIG_PM
1155 deferred:
1156 #endif
1157         return NETDEV_TX_OK;
1158 }
1159 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1160
1161 /*-------------------------------------------------------------------------*/
1162
1163 // tasklet (work deferred from completions, in_irq) or timer
1164
1165 static void usbnet_bh (unsigned long param)
1166 {
1167         struct usbnet           *dev = (struct usbnet *) param;
1168         struct sk_buff          *skb;
1169         struct skb_data         *entry;
1170
1171         while ((skb = skb_dequeue (&dev->done))) {
1172                 entry = (struct skb_data *) skb->cb;
1173                 switch (entry->state) {
1174                 case rx_done:
1175                         entry->state = rx_cleanup;
1176                         rx_process (dev, skb);
1177                         continue;
1178                 case tx_done:
1179                 case rx_cleanup:
1180                         usb_free_urb (entry->urb);
1181                         dev_kfree_skb (skb);
1182                         continue;
1183                 default:
1184                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1185                 }
1186         }
1187
1188         // waiting for all pending urbs to complete?
1189         if (dev->wait) {
1190                 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1191                         wake_up (dev->wait);
1192                 }
1193
1194         // or are we maybe short a few urbs?
1195         } else if (netif_running (dev->net) &&
1196                    netif_device_present (dev->net) &&
1197                    !timer_pending (&dev->delay) &&
1198                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1199                 int     temp = dev->rxq.qlen;
1200                 int     qlen = RX_QLEN (dev);
1201
1202                 if (temp < qlen) {
1203                         struct urb      *urb;
1204                         int             i;
1205
1206                         // don't refill the queue all at once
1207                         for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1208                                 urb = usb_alloc_urb (0, GFP_ATOMIC);
1209                                 if (urb != NULL) {
1210                                         if (rx_submit (dev, urb, GFP_ATOMIC) ==
1211                                             -ENOLINK)
1212                                                 return;
1213                                 }
1214                         }
1215                         if (temp != dev->rxq.qlen)
1216                                 netif_dbg(dev, link, dev->net,
1217                                           "rxqlen %d --> %d\n",
1218                                           temp, dev->rxq.qlen);
1219                         if (dev->rxq.qlen < qlen)
1220                                 tasklet_schedule (&dev->bh);
1221                 }
1222                 if (dev->txq.qlen < TX_QLEN (dev))
1223                         netif_wake_queue (dev->net);
1224         }
1225 }
1226
1227
1228 /*-------------------------------------------------------------------------
1229  *
1230  * USB Device Driver support
1231  *
1232  *-------------------------------------------------------------------------*/
1233
1234 // precondition: never called in_interrupt
1235
1236 void usbnet_disconnect (struct usb_interface *intf)
1237 {
1238         struct usbnet           *dev;
1239         struct usb_device       *xdev;
1240         struct net_device       *net;
1241
1242         dev = usb_get_intfdata(intf);
1243         usb_set_intfdata(intf, NULL);
1244         if (!dev)
1245                 return;
1246
1247         xdev = interface_to_usbdev (intf);
1248
1249         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1250                    intf->dev.driver->name,
1251                    xdev->bus->bus_name, xdev->devpath,
1252                    dev->driver_info->description);
1253
1254         net = dev->net;
1255         unregister_netdev (net);
1256
1257         cancel_work_sync(&dev->kevent);
1258
1259         if (dev->driver_info->unbind)
1260                 dev->driver_info->unbind (dev, intf);
1261
1262         free_netdev(net);
1263         usb_put_dev (xdev);
1264 }
1265 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1266
1267 static const struct net_device_ops usbnet_netdev_ops = {
1268         .ndo_open               = usbnet_open,
1269         .ndo_stop               = usbnet_stop,
1270         .ndo_start_xmit         = usbnet_start_xmit,
1271         .ndo_tx_timeout         = usbnet_tx_timeout,
1272         .ndo_change_mtu         = usbnet_change_mtu,
1273         .ndo_set_mac_address    = eth_mac_addr,
1274         .ndo_validate_addr      = eth_validate_addr,
1275 };
1276
1277 /*-------------------------------------------------------------------------*/
1278
1279 // precondition: never called in_interrupt
1280
1281 static struct device_type wlan_type = {
1282         .name   = "wlan",
1283 };
1284
1285 static struct device_type wwan_type = {
1286         .name   = "wwan",
1287 };
1288
1289 int
1290 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1291 {
1292         struct usbnet                   *dev;
1293         struct net_device               *net;
1294         struct usb_host_interface       *interface;
1295         struct driver_info              *info;
1296         struct usb_device               *xdev;
1297         int                             status;
1298         const char                      *name;
1299         struct usb_driver       *driver = to_usb_driver(udev->dev.driver);
1300
1301         /* usbnet already took usb runtime pm, so have to enable the feature
1302          * for usb interface, otherwise usb_autopm_get_interface may return
1303          * failure if USB_SUSPEND(RUNTIME_PM) is enabled.
1304          */
1305         if (!driver->supports_autosuspend) {
1306                 driver->supports_autosuspend = 1;
1307                 pm_runtime_enable(&udev->dev);
1308         }
1309
1310         name = udev->dev.driver->name;
1311         info = (struct driver_info *) prod->driver_info;
1312         if (!info) {
1313                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1314                 return -ENODEV;
1315         }
1316         xdev = interface_to_usbdev (udev);
1317         interface = udev->cur_altsetting;
1318
1319         usb_get_dev (xdev);
1320
1321         status = -ENOMEM;
1322
1323         // set up our own records
1324         net = alloc_etherdev(sizeof(*dev));
1325         if (!net) {
1326                 dbg ("can't kmalloc dev");
1327                 goto out;
1328         }
1329
1330         /* netdev_printk() needs this so do it as early as possible */
1331         SET_NETDEV_DEV(net, &udev->dev);
1332
1333         dev = netdev_priv(net);
1334         dev->udev = xdev;
1335         dev->intf = udev;
1336         dev->driver_info = info;
1337         dev->driver_name = name;
1338         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1339                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1340         skb_queue_head_init (&dev->rxq);
1341         skb_queue_head_init (&dev->txq);
1342         skb_queue_head_init (&dev->done);
1343         skb_queue_head_init(&dev->rxq_pause);
1344         dev->bh.func = usbnet_bh;
1345         dev->bh.data = (unsigned long) dev;
1346         INIT_WORK (&dev->kevent, kevent);
1347         init_usb_anchor(&dev->deferred);
1348         dev->delay.function = usbnet_bh;
1349         dev->delay.data = (unsigned long) dev;
1350         init_timer (&dev->delay);
1351         mutex_init (&dev->phy_mutex);
1352
1353         dev->net = net;
1354         strcpy (net->name, "usb%d");
1355         memcpy (net->dev_addr, node_id, sizeof node_id);
1356
1357         /* rx and tx sides can use different message sizes;
1358          * bind() should set rx_urb_size in that case.
1359          */
1360         dev->hard_mtu = net->mtu + net->hard_header_len;
1361 #if 0
1362 // dma_supported() is deeply broken on almost all architectures
1363         // possible with some EHCI controllers
1364         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1365                 net->features |= NETIF_F_HIGHDMA;
1366 #endif
1367
1368         net->netdev_ops = &usbnet_netdev_ops;
1369         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1370         net->ethtool_ops = &usbnet_ethtool_ops;
1371
1372         // allow device-specific bind/init procedures
1373         // NOTE net->name still not usable ...
1374         if (info->bind) {
1375                 status = info->bind (dev, udev);
1376                 if (status < 0)
1377                         goto out1;
1378
1379                 // heuristic:  "usb%d" for links we know are two-host,
1380                 // else "eth%d" when there's reasonable doubt.  userspace
1381                 // can rename the link if it knows better.
1382                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1383                     (net->dev_addr [0] & 0x02) == 0)
1384                         strcpy (net->name, "eth%d");
1385                 /* WLAN devices should always be named "wlan%d" */
1386                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1387                         strcpy(net->name, "wlan%d");
1388                 /* WWAN devices should always be named "wwan%d" */
1389                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1390                         strcpy(net->name, "wwan%d");
1391
1392                 /* maybe the remote can't receive an Ethernet MTU */
1393                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1394                         net->mtu = dev->hard_mtu - net->hard_header_len;
1395         } else if (!info->in || !info->out)
1396                 status = usbnet_get_endpoints (dev, udev);
1397         else {
1398                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1399                 dev->out = usb_sndbulkpipe (xdev, info->out);
1400                 if (!(info->flags & FLAG_NO_SETINT))
1401                         status = usb_set_interface (xdev,
1402                                 interface->desc.bInterfaceNumber,
1403                                 interface->desc.bAlternateSetting);
1404                 else
1405                         status = 0;
1406
1407         }
1408         if (status >= 0 && dev->status)
1409                 status = init_status (dev, udev);
1410         if (status < 0)
1411                 goto out3;
1412
1413         if (!dev->rx_urb_size)
1414                 dev->rx_urb_size = dev->hard_mtu;
1415         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1416
1417         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1418                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1419         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1420                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1421
1422         status = register_netdev (net);
1423         if (status)
1424                 goto out3;
1425         netif_info(dev, probe, dev->net,
1426                    "register '%s' at usb-%s-%s, %s, %pM\n",
1427                    udev->dev.driver->name,
1428                    xdev->bus->bus_name, xdev->devpath,
1429                    dev->driver_info->description,
1430                    net->dev_addr);
1431
1432         // ok, it's ready to go.
1433         usb_set_intfdata (udev, dev);
1434
1435         netif_device_attach (net);
1436
1437         if (dev->driver_info->flags & FLAG_LINK_INTR)
1438                 netif_carrier_off(net);
1439
1440         return 0;
1441
1442 out3:
1443         if (info->unbind)
1444                 info->unbind (dev, udev);
1445 out1:
1446         free_netdev(net);
1447 out:
1448         usb_put_dev(xdev);
1449         return status;
1450 }
1451 EXPORT_SYMBOL_GPL(usbnet_probe);
1452
1453 /*-------------------------------------------------------------------------*/
1454
1455 /*
1456  * suspend the whole driver as soon as the first interface is suspended
1457  * resume only when the last interface is resumed
1458  */
1459
1460 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1461 {
1462         struct usbnet           *dev = usb_get_intfdata(intf);
1463
1464         if (!dev->suspend_count++) {
1465                 spin_lock_irq(&dev->txq.lock);
1466                 /* don't autosuspend while transmitting */
1467                 if (dev->txq.qlen && (message.event & PM_EVENT_AUTO)) {
1468                         spin_unlock_irq(&dev->txq.lock);
1469                         return -EBUSY;
1470                 } else {
1471                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1472                         spin_unlock_irq(&dev->txq.lock);
1473                 }
1474                 /*
1475                  * accelerate emptying of the rx and queues, to avoid
1476                  * having everything error out.
1477                  */
1478                 netif_device_detach (dev->net);
1479                 usbnet_terminate_urbs(dev);
1480                 usb_kill_urb(dev->interrupt);
1481
1482                 /*
1483                  * reattach so runtime management can use and
1484                  * wake the device
1485                  */
1486                 netif_device_attach (dev->net);
1487         }
1488         return 0;
1489 }
1490 EXPORT_SYMBOL_GPL(usbnet_suspend);
1491
1492 int usbnet_resume (struct usb_interface *intf)
1493 {
1494         struct usbnet           *dev = usb_get_intfdata(intf);
1495         struct sk_buff          *skb;
1496         struct urb              *res;
1497         int                     retval;
1498
1499         if (!--dev->suspend_count) {
1500                 spin_lock_irq(&dev->txq.lock);
1501                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1502
1503                         skb = (struct sk_buff *)res->context;
1504                         retval = usb_submit_urb(res, GFP_ATOMIC);
1505                         if (retval < 0) {
1506                                 dev_kfree_skb_any(skb);
1507                                 usb_free_urb(res);
1508                                 usb_autopm_put_interface_async(dev->intf);
1509                         } else {
1510                                 dev->net->trans_start = jiffies;
1511                                 __skb_queue_tail(&dev->txq, skb);
1512                         }
1513                 }
1514
1515                 smp_mb();
1516                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1517                 spin_unlock_irq(&dev->txq.lock);
1518                 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1519                         netif_start_queue(dev->net);
1520                 tasklet_schedule (&dev->bh);
1521         }
1522         return 0;
1523 }
1524 EXPORT_SYMBOL_GPL(usbnet_resume);
1525
1526
1527 /*-------------------------------------------------------------------------*/
1528
1529 static int __init usbnet_init(void)
1530 {
1531         /* compiler should optimize this out */
1532         BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1533                         < sizeof (struct skb_data));
1534
1535         random_ether_addr(node_id);
1536         return 0;
1537 }
1538 module_init(usbnet_init);
1539
1540 static void __exit usbnet_exit(void)
1541 {
1542 }
1543 module_exit(usbnet_exit);
1544
1545 MODULE_AUTHOR("David Brownell");
1546 MODULE_DESCRIPTION("USB network driver framework");
1547 MODULE_LICENSE("GPL");