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         clear_bit(EVENT_DEV_OPEN, &dev->flags);
 649         netif_stop_queue (net);
 650
 651         netif_info(dev, ifdown, dev->net,
 652                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 653                    net->stats.rx_packets, net->stats.tx_packets,
 654                    net->stats.rx_errors, net->stats.tx_errors);
 655
 656         /* allow minidriver to stop correctly (wireless devices to turn off
 657          * radio etc) */
 658         if (info->stop) {
 659                 retval = info->stop(dev);
 660                 if (retval < 0)
 661                         netif_info(dev, ifdown, dev->net,
 662                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
 663                                    retval,
 664                                    dev->udev->bus->bus_name, dev->udev->devpath,
 665                                    info->description);
 666         }
 667
 668         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 669                 usbnet_terminate_urbs(dev);
 670
 671         usb_kill_urb(dev->interrupt);
 672
 673         usbnet_purge_paused_rxq(dev);
 674
 675         /* deferred work (task, timer, softirq) must also stop.
 676          * can't flush_scheduled_work() until we drop rtnl (later),
 677          * else workers could deadlock; so make workers a NOP.
 678          */
 679         dev->flags = 0;
 680         del_timer_sync (&dev->delay);
 681         tasklet_kill (&dev->bh);
 682         if (info->manage_power)
 683                 info->manage_power(dev, 0);
 684         else
 685                 usb_autopm_put_interface(dev->intf);
 686
 687         return 0;
 688 }
 689 EXPORT_SYMBOL_GPL(usbnet_stop);
 690
 691 /*-------------------------------------------------------------------------*/
 692
 693 // posts reads, and enables write queuing
 694
 695 // precondition: never called in_interrupt
 696
 697 int usbnet_open (struct net_device *net)
 698 {
 699         struct usbnet           *dev = netdev_priv(net);
 700         int                     retval;
 701         struct driver_info      *info = dev->driver_info;
 702
 703         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 704                 netif_info(dev, ifup, dev->net,
 705                            "resumption 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_nopm;
 711         }
 712
 713         // put into "known safe" state
 714         if (info->reset && (retval = info->reset (dev)) < 0) {
 715                 netif_info(dev, ifup, dev->net,
 716                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 717                            retval,
 718                            dev->udev->bus->bus_name,
 719                            dev->udev->devpath,
 720                            info->description);
 721                 goto done;
 722         }
 723
 724         // insist peer be connected
 725         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 726                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 727                 goto done;
 728         }
 729
 730         /* start any status interrupt transfer */
 731         if (dev->interrupt) {
 732                 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 733                 if (retval < 0) {
 734                         netif_err(dev, ifup, dev->net,
 735                                   "intr submit %d\n", retval);
 736                         goto done;
 737                 }
 738         }
 739
 740         set_bit(EVENT_DEV_OPEN, &dev->flags);
 741         netif_start_queue (net);
 742         netif_info(dev, ifup, dev->net,
 743                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 744                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 745                    dev->net->mtu,
 746                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 747                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 748                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 749                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 750                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 751                    "simple");
 752
 753         // delay posting reads until we're fully open
 754         tasklet_schedule (&dev->bh);
 755         if (info->manage_power) {
 756                 retval = info->manage_power(dev, 1);
 757                 if (retval < 0)
 758                         goto done;
 759                 usb_autopm_put_interface(dev->intf);
 760         }
 761         return retval;
 762
 763 done:
 764         usb_autopm_put_interface(dev->intf);
 765 done_nopm:
 766         return retval;
 767 }
 768 EXPORT_SYMBOL_GPL(usbnet_open);
 769
 770 /*-------------------------------------------------------------------------*/
 771
 772 /* ethtool methods; minidrivers may need to add some more, but
 773  * they'll probably want to use this base set.
 774  */
 775
 776 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 777 {
 778         struct usbnet *dev = netdev_priv(net);
 779
 780         if (!dev->mii.mdio_read)
 781                 return -EOPNOTSUPP;
 782
 783         return mii_ethtool_gset(&dev->mii, cmd);
 784 }
 785 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 786
 787 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 788 {
 789         struct usbnet *dev = netdev_priv(net);
 790         int retval;
 791
 792         if (!dev->mii.mdio_write)
 793                 return -EOPNOTSUPP;
 794
 795         retval = mii_ethtool_sset(&dev->mii, cmd);
 796
 797         /* link speed/duplex might have changed */
 798         if (dev->driver_info->link_reset)
 799                 dev->driver_info->link_reset(dev);
 800
 801         return retval;
 802
 803 }
 804 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 805
 806 u32 usbnet_get_link (struct net_device *net)
 807 {
 808         struct usbnet *dev = netdev_priv(net);
 809
 810         /* If a check_connect is defined, return its result */
 811         if (dev->driver_info->check_connect)
 812                 return dev->driver_info->check_connect (dev) == 0;
 813
 814         /* if the device has mii operations, use those */
 815         if (dev->mii.mdio_read)
 816                 return mii_link_ok(&dev->mii);
 817
 818         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 819         return ethtool_op_get_link(net);
 820 }
 821 EXPORT_SYMBOL_GPL(usbnet_get_link);
 822
 823 int usbnet_nway_reset(struct net_device *net)
 824 {
 825         struct usbnet *dev = netdev_priv(net);
 826
 827         if (!dev->mii.mdio_write)
 828                 return -EOPNOTSUPP;
 829
 830         return mii_nway_restart(&dev->mii);
 831 }
 832 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 833
 834 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 835 {
 836         struct usbnet *dev = netdev_priv(net);
 837
 838         strncpy (info->driver, dev->driver_name, sizeof info->driver);
 839         strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 840         strncpy (info->fw_version, dev->driver_info->description,
 841                 sizeof info->fw_version);
 842         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 843 }
 844 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 845
 846 u32 usbnet_get_msglevel (struct net_device *net)
 847 {
 848         struct usbnet *dev = netdev_priv(net);
 849
 850         return dev->msg_enable;
 851 }
 852 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 853
 854 void usbnet_set_msglevel (struct net_device *net, u32 level)
 855 {
 856         struct usbnet *dev = netdev_priv(net);
 857
 858         dev->msg_enable = level;
 859 }
 860 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 861
 862 /* drivers may override default ethtool_ops in their bind() routine */
 863 static const struct ethtool_ops usbnet_ethtool_ops = {
 864         .get_settings           = usbnet_get_settings,
 865         .set_settings           = usbnet_set_settings,
 866         .get_link               = usbnet_get_link,
 867         .nway_reset             = usbnet_nway_reset,
 868         .get_drvinfo            = usbnet_get_drvinfo,
 869         .get_msglevel           = usbnet_get_msglevel,
 870         .set_msglevel           = usbnet_set_msglevel,
 871 };
 872
 873 /*-------------------------------------------------------------------------*/
 874
 875 /* work that cannot be done in interrupt context uses keventd.
 876  *
 877  * NOTE:  with 2.5 we could do more of this using completion callbacks,
 878  * especially now that control transfers can be queued.
 879  */
 880 static void
 881 kevent (struct work_struct *work)
 882 {
 883         struct usbnet           *dev =
 884                 container_of(work, struct usbnet, kevent);
 885         int                     status;
 886
 887         /* usb_clear_halt() needs a thread context */
 888         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 889                 unlink_urbs (dev, &dev->txq);
 890                 status = usb_autopm_get_interface(dev->intf);
 891                 if (status < 0)
 892                         goto fail_pipe;
 893                 status = usb_clear_halt (dev->udev, dev->out);
 894                 usb_autopm_put_interface(dev->intf);
 895                 if (status < 0 &&
 896                     status != -EPIPE &&
 897                     status != -ESHUTDOWN) {
 898                         if (netif_msg_tx_err (dev))
 899 fail_pipe:
 900                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
 901                                            status);
 902                 } else {
 903                         clear_bit (EVENT_TX_HALT, &dev->flags);
 904                         if (status != -ESHUTDOWN)
 905                                 netif_wake_queue (dev->net);
 906                 }
 907         }
 908         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 909                 unlink_urbs (dev, &dev->rxq);
 910                 status = usb_autopm_get_interface(dev->intf);
 911                 if (status < 0)
 912                         goto fail_halt;
 913                 status = usb_clear_halt (dev->udev, dev->in);
 914                 usb_autopm_put_interface(dev->intf);
 915                 if (status < 0 &&
 916                     status != -EPIPE &&
 917                     status != -ESHUTDOWN) {
 918                         if (netif_msg_rx_err (dev))
 919 fail_halt:
 920                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
 921                                            status);
 922                 } else {
 923                         clear_bit (EVENT_RX_HALT, &dev->flags);
 924                         tasklet_schedule (&dev->bh);
 925                 }
 926         }
 927
 928         /* tasklet could resubmit itself forever if memory is tight */
 929         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 930                 struct urb      *urb = NULL;
 931                 int resched = 1;
 932
 933                 if (netif_running (dev->net))
 934                         urb = usb_alloc_urb (0, GFP_KERNEL);
 935                 else
 936                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 937                 if (urb != NULL) {
 938                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
 939                         status = usb_autopm_get_interface(dev->intf);
 940                         if (status < 0) {
 941                                 usb_free_urb(urb);
 942                                 goto fail_lowmem;
 943                         }
 944                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
 945                                 resched = 0;
 946                         usb_autopm_put_interface(dev->intf);
 947 fail_lowmem:
 948                         if (resched)
 949                                 tasklet_schedule (&dev->bh);
 950                 }
 951         }
 952
 953         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 954                 struct driver_info      *info = dev->driver_info;
 955                 int                     retval = 0;
 956
 957                 clear_bit (EVENT_LINK_RESET, &dev->flags);
 958                 status = usb_autopm_get_interface(dev->intf);
 959                 if (status < 0)
 960                         goto skip_reset;
 961                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 962                         usb_autopm_put_interface(dev->intf);
 963 skip_reset:
 964                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
 965                                     retval,
 966                                     dev->udev->bus->bus_name,
 967                                     dev->udev->devpath,
 968                                     info->description);
 969                 } else {
 970                         usb_autopm_put_interface(dev->intf);
 971                 }
 972         }
 973
 974         if (dev->flags)
 975                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
 976 }
 977
 978 /*-------------------------------------------------------------------------*/
 979
 980 static void tx_complete (struct urb *urb)
 981 {
 982         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 983         struct skb_data         *entry = (struct skb_data *) skb->cb;
 984         struct usbnet           *dev = entry->dev;
 985
 986         if (urb->status == 0) {
 987                 if (!(dev->driver_info->flags & FLAG_MULTI_PACKET))
 988                         dev->net->stats.tx_packets++;
 989                 dev->net->stats.tx_bytes += entry->length;
 990         } else {
 991                 dev->net->stats.tx_errors++;
 992
 993                 switch (urb->status) {
 994                 case -EPIPE:
 995                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
 996                         break;
 997
 998                 /* software-driven interface shutdown */
 999                 case -ECONNRESET:               // async unlink
1000                 case -ESHUTDOWN:                // hardware gone
1001                         break;
1002
1003                 // like rx, tx gets controller i/o faults during khubd delays
1004                 // and so it uses the same throttling mechanism.
1005                 case -EPROTO:
1006                 case -ETIME:
1007                 case -EILSEQ:
1008                         usb_mark_last_busy(dev->udev);
1009                         if (!timer_pending (&dev->delay)) {
1010                                 mod_timer (&dev->delay,
1011                                         jiffies + THROTTLE_JIFFIES);
1012                                 netif_dbg(dev, link, dev->net,
1013                                           "tx throttle %d\n", urb->status);
1014                         }
1015                         netif_stop_queue (dev->net);
1016                         break;
1017                 default:
1018                         netif_dbg(dev, tx_err, dev->net,
1019                                   "tx err %d\n", entry->urb->status);
1020                         break;
1021                 }
1022         }
1023
1024         usb_autopm_put_interface_async(dev->intf);
1025         urb->dev = NULL;
1026         entry->state = tx_done;
1027         defer_bh(dev, skb, &dev->txq);
1028 }
1029
1030 /*-------------------------------------------------------------------------*/
1031
1032 void usbnet_tx_timeout (struct net_device *net)
1033 {
1034         struct usbnet           *dev = netdev_priv(net);
1035
1036         unlink_urbs (dev, &dev->txq);
1037         tasklet_schedule (&dev->bh);
1038
1039         // FIXME: device recovery -- reset?
1040 }
1041 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1042
1043 /*-------------------------------------------------------------------------*/
1044
1045 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1046                                      struct net_device *net)
1047 {
1048         struct usbnet           *dev = netdev_priv(net);
1049         int                     length;
1050         struct urb              *urb = NULL;
1051         struct skb_data         *entry;
1052         struct driver_info      *info = dev->driver_info;
1053         unsigned long           flags;
1054         int retval;
1055
1056         // some devices want funky USB-level framing, for
1057         // win32 driver (usually) and/or hardware quirks
1058         if (info->tx_fixup) {
1059                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1060                 if (!skb) {
1061                         if (netif_msg_tx_err(dev)) {
1062                                 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1063                                 goto drop;
1064                         } else {
1065                                 /* cdc_ncm collected packet; waits for more */
1066                                 goto not_drop;
1067                         }
1068                 }
1069         }
1070         length = skb->len;
1071
1072         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1073                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1074                 goto drop;
1075         }
1076
1077         entry = (struct skb_data *) skb->cb;
1078         entry->urb = urb;
1079         entry->dev = dev;
1080         entry->state = tx_start;
1081         entry->length = length;
1082
1083         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1084                         skb->data, skb->len, tx_complete, skb);
1085
1086         /* don't assume the hardware handles USB_ZERO_PACKET
1087          * NOTE:  strictly conforming cdc-ether devices should expect
1088          * the ZLP here, but ignore the one-byte packet.
1089          * NOTE2: CDC NCM specification is different from CDC ECM when
1090          * handling ZLP/short packets, so cdc_ncm driver will make short
1091          * packet itself if needed.
1092          */
1093         if (length % dev->maxpacket == 0) {
1094                 if (!(info->flags & FLAG_SEND_ZLP)) {
1095                         if (!(info->flags & FLAG_MULTI_PACKET)) {
1096                                 urb->transfer_buffer_length++;
1097                                 if (skb_tailroom(skb)) {
1098                                         skb->data[skb->len] = 0;
1099                                         __skb_put(skb, 1);
1100                                 }
1101                         }
1102                 } else
1103                         urb->transfer_flags |= URB_ZERO_PACKET;
1104         }
1105
1106         spin_lock_irqsave(&dev->txq.lock, flags);
1107         retval = usb_autopm_get_interface_async(dev->intf);
1108         if (retval < 0) {
1109                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1110                 goto drop;
1111         }
1112
1113 #ifdef CONFIG_PM
1114         /* if this triggers the device is still a sleep */
1115         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1116                 /* transmission will be done in resume */
1117                 usb_anchor_urb(urb, &dev->deferred);
1118                 /* no use to process more packets */
1119                 netif_stop_queue(net);
1120                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1121                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1122                 goto deferred;
1123         }
1124 #endif
1125
1126         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1127         case -EPIPE:
1128                 netif_stop_queue (net);
1129                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1130                 usb_autopm_put_interface_async(dev->intf);
1131                 break;
1132         default:
1133                 usb_autopm_put_interface_async(dev->intf);
1134                 netif_dbg(dev, tx_err, dev->net,
1135                           "tx: submit urb err %d\n", retval);
1136                 break;
1137         case 0:
1138                 net->trans_start = jiffies;
1139                 __skb_queue_tail (&dev->txq, skb);
1140                 if (dev->txq.qlen >= TX_QLEN (dev))
1141                         netif_stop_queue (net);
1142         }
1143         spin_unlock_irqrestore (&dev->txq.lock, flags);
1144
1145         if (retval) {
1146                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1147 drop:
1148                 dev->net->stats.tx_dropped++;
1149 not_drop:
1150                 if (skb)
1151                         dev_kfree_skb_any (skb);
1152                 usb_free_urb (urb);
1153         } else
1154                 netif_dbg(dev, tx_queued, dev->net,
1155                           "> tx, len %d, type 0x%x\n", length, skb->protocol);
1156 #ifdef CONFIG_PM
1157 deferred:
1158 #endif
1159         return NETDEV_TX_OK;
1160 }
1161 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1162
1163 /*-------------------------------------------------------------------------*/
1164
1165 // tasklet (work deferred from completions, in_irq) or timer
1166
1167 static void usbnet_bh (unsigned long param)
1168 {
1169         struct usbnet           *dev = (struct usbnet *) param;
1170         struct sk_buff          *skb;
1171         struct skb_data         *entry;
1172
1173         while ((skb = skb_dequeue (&dev->done))) {
1174                 entry = (struct skb_data *) skb->cb;
1175                 switch (entry->state) {
1176                 case rx_done:
1177                         entry->state = rx_cleanup;
1178                         rx_process (dev, skb);
1179                         continue;
1180                 case tx_done:
1181                 case rx_cleanup:
1182                         usb_free_urb (entry->urb);
1183                         dev_kfree_skb (skb);
1184                         continue;
1185                 default:
1186                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1187                 }
1188         }
1189
1190         // waiting for all pending urbs to complete?
1191         if (dev->wait) {
1192                 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1193                         wake_up (dev->wait);
1194                 }
1195
1196         // or are we maybe short a few urbs?
1197         } else if (netif_running (dev->net) &&
1198                    netif_device_present (dev->net) &&
1199                    !timer_pending (&dev->delay) &&
1200                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1201                 int     temp = dev->rxq.qlen;
1202                 int     qlen = RX_QLEN (dev);
1203
1204                 if (temp < qlen) {
1205                         struct urb      *urb;
1206                         int             i;
1207
1208                         // don't refill the queue all at once
1209                         for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1210                                 urb = usb_alloc_urb (0, GFP_ATOMIC);
1211                                 if (urb != NULL) {
1212                                         if (rx_submit (dev, urb, GFP_ATOMIC) ==
1213                                             -ENOLINK)
1214                                                 return;
1215                                 }
1216                         }
1217                         if (temp != dev->rxq.qlen)
1218                                 netif_dbg(dev, link, dev->net,
1219                                           "rxqlen %d --> %d\n",
1220                                           temp, dev->rxq.qlen);
1221                         if (dev->rxq.qlen < qlen)
1222                                 tasklet_schedule (&dev->bh);
1223                 }
1224                 if (dev->txq.qlen < TX_QLEN (dev))
1225                         netif_wake_queue (dev->net);
1226         }
1227 }
1228
1229
1230 /*-------------------------------------------------------------------------
1231  *
1232  * USB Device Driver support
1233  *
1234  *-------------------------------------------------------------------------*/
1235
1236 // precondition: never called in_interrupt
1237
1238 void usbnet_disconnect (struct usb_interface *intf)
1239 {
1240         struct usbnet           *dev;
1241         struct usb_device       *xdev;
1242         struct net_device       *net;
1243
1244         dev = usb_get_intfdata(intf);
1245         usb_set_intfdata(intf, NULL);
1246         if (!dev)
1247                 return;
1248
1249         xdev = interface_to_usbdev (intf);
1250
1251         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1252                    intf->dev.driver->name,
1253                    xdev->bus->bus_name, xdev->devpath,
1254                    dev->driver_info->description);
1255
1256         net = dev->net;
1257         unregister_netdev (net);
1258
1259         cancel_work_sync(&dev->kevent);
1260
1261         if (dev->driver_info->unbind)
1262                 dev->driver_info->unbind (dev, intf);
1263
1264         usb_kill_urb(dev->interrupt);
1265         usb_free_urb(dev->interrupt);
1266
1267         free_netdev(net);
1268         usb_put_dev (xdev);
1269 }
1270 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1271
1272 static const struct net_device_ops usbnet_netdev_ops = {
1273         .ndo_open               = usbnet_open,
1274         .ndo_stop               = usbnet_stop,
1275         .ndo_start_xmit         = usbnet_start_xmit,
1276         .ndo_tx_timeout         = usbnet_tx_timeout,
1277         .ndo_change_mtu         = usbnet_change_mtu,
1278         .ndo_set_mac_address    = eth_mac_addr,
1279         .ndo_validate_addr      = eth_validate_addr,
1280 };
1281
1282 /*-------------------------------------------------------------------------*/
1283
1284 // precondition: never called in_interrupt
1285
1286 static struct device_type wlan_type = {
1287         .name   = "wlan",
1288 };
1289
1290 static struct device_type wwan_type = {
1291         .name   = "wwan",
1292 };
1293
1294 int
1295 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1296 {
1297         struct usbnet                   *dev;
1298         struct net_device               *net;
1299         struct usb_host_interface       *interface;
1300         struct driver_info              *info;
1301         struct usb_device               *xdev;
1302         int                             status;
1303         const char                      *name;
1304         struct usb_driver       *driver = to_usb_driver(udev->dev.driver);
1305
1306         /* usbnet already took usb runtime pm, so have to enable the feature
1307          * for usb interface, otherwise usb_autopm_get_interface may return
1308          * failure if USB_SUSPEND(RUNTIME_PM) is enabled.
1309          */
1310         if (!driver->supports_autosuspend) {
1311                 driver->supports_autosuspend = 1;
1312                 pm_runtime_enable(&udev->dev);
1313         }
1314
1315         name = udev->dev.driver->name;
1316         info = (struct driver_info *) prod->driver_info;
1317         if (!info) {
1318                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1319                 return -ENODEV;
1320         }
1321         xdev = interface_to_usbdev (udev);
1322         interface = udev->cur_altsetting;
1323
1324         usb_get_dev (xdev);
1325
1326         status = -ENOMEM;
1327
1328         // set up our own records
1329         net = alloc_etherdev(sizeof(*dev));
1330         if (!net) {
1331                 dbg ("can't kmalloc dev");
1332                 goto out;
1333         }
1334
1335         /* netdev_printk() needs this so do it as early as possible */
1336         SET_NETDEV_DEV(net, &udev->dev);
1337
1338         dev = netdev_priv(net);
1339         dev->udev = xdev;
1340         dev->intf = udev;
1341         dev->driver_info = info;
1342         dev->driver_name = name;
1343         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1344                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1345         skb_queue_head_init (&dev->rxq);
1346         skb_queue_head_init (&dev->txq);
1347         skb_queue_head_init (&dev->done);
1348         skb_queue_head_init(&dev->rxq_pause);
1349         dev->bh.func = usbnet_bh;
1350         dev->bh.data = (unsigned long) dev;
1351         INIT_WORK (&dev->kevent, kevent);
1352         init_usb_anchor(&dev->deferred);
1353         dev->delay.function = usbnet_bh;
1354         dev->delay.data = (unsigned long) dev;
1355         init_timer (&dev->delay);
1356         mutex_init (&dev->phy_mutex);
1357
1358         dev->net = net;
1359         strcpy (net->name, "usb%d");
1360         memcpy (net->dev_addr, node_id, sizeof node_id);
1361
1362         /* rx and tx sides can use different message sizes;
1363          * bind() should set rx_urb_size in that case.
1364          */
1365         dev->hard_mtu = net->mtu + net->hard_header_len;
1366 #if 0
1367 // dma_supported() is deeply broken on almost all architectures
1368         // possible with some EHCI controllers
1369         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1370                 net->features |= NETIF_F_HIGHDMA;
1371 #endif
1372
1373         net->netdev_ops = &usbnet_netdev_ops;
1374         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1375         net->ethtool_ops = &usbnet_ethtool_ops;
1376
1377         // allow device-specific bind/init procedures
1378         // NOTE net->name still not usable ...
1379         if (info->bind) {
1380                 status = info->bind (dev, udev);
1381                 if (status < 0)
1382                         goto out1;
1383
1384                 // heuristic:  "usb%d" for links we know are two-host,
1385                 // else "eth%d" when there's reasonable doubt.  userspace
1386                 // can rename the link if it knows better.
1387                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1388                     ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1389                      (net->dev_addr [0] & 0x02) == 0))
1390                         strcpy (net->name, "eth%d");
1391                 /* WLAN devices should always be named "wlan%d" */
1392                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1393                         strcpy(net->name, "wlan%d");
1394                 /* WWAN devices should always be named "wwan%d" */
1395                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1396                         strcpy(net->name, "wwan%d");
1397
1398                 /* maybe the remote can't receive an Ethernet MTU */
1399                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1400                         net->mtu = dev->hard_mtu - net->hard_header_len;
1401         } else if (!info->in || !info->out)
1402                 status = usbnet_get_endpoints (dev, udev);
1403         else {
1404                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1405                 dev->out = usb_sndbulkpipe (xdev, info->out);
1406                 if (!(info->flags & FLAG_NO_SETINT))
1407                         status = usb_set_interface (xdev,
1408                                 interface->desc.bInterfaceNumber,
1409                                 interface->desc.bAlternateSetting);
1410                 else
1411                         status = 0;
1412
1413         }
1414         if (status >= 0 && dev->status)
1415                 status = init_status (dev, udev);
1416         if (status < 0)
1417                 goto out3;
1418
1419         if (!dev->rx_urb_size)
1420                 dev->rx_urb_size = dev->hard_mtu;
1421         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1422
1423         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1424                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1425         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1426                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1427
1428         status = register_netdev (net);
1429         if (status)
1430                 goto out3;
1431         netif_info(dev, probe, dev->net,
1432                    "register '%s' at usb-%s-%s, %s, %pM\n",
1433                    udev->dev.driver->name,
1434                    xdev->bus->bus_name, xdev->devpath,
1435                    dev->driver_info->description,
1436                    net->dev_addr);
1437
1438         // ok, it's ready to go.
1439         usb_set_intfdata (udev, dev);
1440
1441         netif_device_attach (net);
1442
1443         if (dev->driver_info->flags & FLAG_LINK_INTR)
1444                 netif_carrier_off(net);
1445
1446         return 0;
1447
1448 out3:
1449         if (info->unbind)
1450                 info->unbind (dev, udev);
1451 out1:
1452         free_netdev(net);
1453 out:
1454         usb_put_dev(xdev);
1455         return status;
1456 }
1457 EXPORT_SYMBOL_GPL(usbnet_probe);
1458
1459 /*-------------------------------------------------------------------------*/
1460
1461 /*
1462  * suspend the whole driver as soon as the first interface is suspended
1463  * resume only when the last interface is resumed
1464  */
1465
1466 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1467 {
1468         struct usbnet           *dev = usb_get_intfdata(intf);
1469
1470         if (!dev->suspend_count++) {
1471                 spin_lock_irq(&dev->txq.lock);
1472                 /* don't autosuspend while transmitting */
1473                 if (dev->txq.qlen && (message.event & PM_EVENT_AUTO)) {
1474                         spin_unlock_irq(&dev->txq.lock);
1475                         return -EBUSY;
1476                 } else {
1477                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1478                         spin_unlock_irq(&dev->txq.lock);
1479                 }
1480                 /*
1481                  * accelerate emptying of the rx and queues, to avoid
1482                  * having everything error out.
1483                  */
1484                 netif_device_detach (dev->net);
1485                 usbnet_terminate_urbs(dev);
1486                 usb_kill_urb(dev->interrupt);
1487
1488                 /*
1489                  * reattach so runtime management can use and
1490                  * wake the device
1491                  */
1492                 netif_device_attach (dev->net);
1493         }
1494         return 0;
1495 }
1496 EXPORT_SYMBOL_GPL(usbnet_suspend);
1497
1498 int usbnet_resume (struct usb_interface *intf)
1499 {
1500         struct usbnet           *dev = usb_get_intfdata(intf);
1501         struct sk_buff          *skb;
1502         struct urb              *res;
1503         int                     retval;
1504
1505         if (!--dev->suspend_count) {
1506                 /* resume interrupt URBs */
1507                 if (dev->interrupt && test_bit(EVENT_DEV_OPEN, &dev->flags))
1508                         usb_submit_urb(dev->interrupt, GFP_NOIO);
1509
1510                 spin_lock_irq(&dev->txq.lock);
1511                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1512
1513                         skb = (struct sk_buff *)res->context;
1514                         retval = usb_submit_urb(res, GFP_ATOMIC);
1515                         if (retval < 0) {
1516                                 dev_kfree_skb_any(skb);
1517                                 usb_free_urb(res);
1518                                 usb_autopm_put_interface_async(dev->intf);
1519                         } else {
1520                                 dev->net->trans_start = jiffies;
1521                                 __skb_queue_tail(&dev->txq, skb);
1522                         }
1523                 }
1524
1525                 smp_mb();
1526                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1527                 spin_unlock_irq(&dev->txq.lock);
1528
1529                 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1530                         if (!(dev->txq.qlen >= TX_QLEN(dev)))
1531                                 netif_start_queue(dev->net);
1532                         tasklet_schedule (&dev->bh);
1533                 }
1534         }
1535         return 0;
1536 }
1537 EXPORT_SYMBOL_GPL(usbnet_resume);
1538
1539
1540 /*-------------------------------------------------------------------------*/
1541
1542 static int __init usbnet_init(void)
1543 {
1544         /* compiler should optimize this out */
1545         BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1546                         < sizeof (struct skb_data));
1547
1548         random_ether_addr(node_id);
1549         return 0;
1550 }
1551 module_init(usbnet_init);
1552
1553 static void __exit usbnet_exit(void)
1554 {
1555 }
1556 module_exit(usbnet_exit);
1557
1558 MODULE_AUTHOR("David Brownell");
1559 MODULE_DESCRIPTION("USB network driver framework");
1560 MODULE_LICENSE("GPL");