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, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /*
  21  * This is a generic "USB networking" framework that works with several
  22  * kinds of full and high speed networking devices:  host-to-host cables,
  23  * smart usb peripherals, and actual Ethernet adapters.
  24  *
  25  * These devices usually differ in terms of control protocols (if they
  26  * even have one!) and sometimes they define new framing to wrap or batch
  27  * Ethernet packets.  Otherwise, they talk to USB pretty much the same,
  28  * so interface (un)binding, endpoint I/O queues, fault handling, and other
  29  * issues can usefully be addressed by this framework.
  30  */
  31
  32 // #define      DEBUG                   // error path messages, extra info
  33 // #define      VERBOSE                 // more; success messages
  34
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/netdevice.h>
  38 #include <linux/etherdevice.h>
  39 #include <linux/ctype.h>
  40 #include <linux/ethtool.h>
  41 #include <linux/workqueue.h>
  42 #include <linux/mii.h>
  43 #include <linux/usb.h>
  44 #include <linux/usb/usbnet.h>
  45 #include <linux/usb/cdc.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  * The goal is to let the USB host controller be busy for 5msec or
  63  * more before an irq is required, under load.  Jumbograms change
  64  * the equation.
  65  */
  66 #define MAX_QUEUE_MEMORY        (60 * 1518)
  67 #define RX_QLEN(dev)            ((dev)->rx_qlen)
  68 #define TX_QLEN(dev)            ((dev)->tx_qlen)
  69
  70 // reawaken network queue this soon after stopping; else watchdog barks
  71 #define TX_TIMEOUT_JIFFIES      (5*HZ)
  72
  73 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
  74  * us (it polls at HZ/4 usually) before we report too many false errors.
  75  */
  76 #define THROTTLE_JIFFIES        (HZ/8)
  77
  78 // between wakeups
  79 #define UNLINK_TIMEOUT_MS       3
  80
  81 /*-------------------------------------------------------------------------*/
  82
  83 // randomly generated ethernet address
  84 static u8       node_id [ETH_ALEN];
  85
  86 static const char driver_name [] = "usbnet";
  87
  88 /* use ethtool to change the level for any given device */
  89 static int msg_level = -1;
  90 module_param (msg_level, int, 0);
  91 MODULE_PARM_DESC (msg_level, "Override default message level");
  92
  93 /*-------------------------------------------------------------------------*/
  94
  95 /* handles CDC Ethernet and many other network "bulk data" interfaces */
  96 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  97 {
  98         int                             tmp;
  99         struct usb_host_interface       *alt = NULL;
 100         struct usb_host_endpoint        *in = NULL, *out = NULL;
 101         struct usb_host_endpoint        *status = NULL;
 102
 103         for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 104                 unsigned        ep;
 105
 106                 in = out = status = NULL;
 107                 alt = intf->altsetting + tmp;
 108
 109                 /* take the first altsetting with in-bulk + out-bulk;
 110                  * remember any status endpoint, just in case;
 111                  * ignore other endpoints and altsettings.
 112                  */
 113                 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 114                         struct usb_host_endpoint        *e;
 115                         int                             intr = 0;
 116
 117                         e = alt->endpoint + ep;
 118                         switch (e->desc.bmAttributes) {
 119                         case USB_ENDPOINT_XFER_INT:
 120                                 if (!usb_endpoint_dir_in(&e->desc))
 121                                         continue;
 122                                 intr = 1;
 123                                 /* FALLTHROUGH */
 124                         case USB_ENDPOINT_XFER_BULK:
 125                                 break;
 126                         default:
 127                                 continue;
 128                         }
 129                         if (usb_endpoint_dir_in(&e->desc)) {
 130                                 if (!intr && !in)
 131                                         in = e;
 132                                 else if (intr && !status)
 133                                         status = e;
 134                         } else {
 135                                 if (!out)
 136                                         out = e;
 137                         }
 138                 }
 139                 if (in && out)
 140                         break;
 141         }
 142         if (!alt || !in || !out)
 143                 return -EINVAL;
 144
 145         if (alt->desc.bAlternateSetting != 0 ||
 146             !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 147                 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 148                                 alt->desc.bAlternateSetting);
 149                 if (tmp < 0)
 150                         return tmp;
 151         }
 152
 153         dev->in = usb_rcvbulkpipe (dev->udev,
 154                         in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 155         dev->out = usb_sndbulkpipe (dev->udev,
 156                         out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 157         dev->status = status;
 158         return 0;
 159 }
 160 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 161
 162 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 163 {
 164         int             tmp = -1, ret;
 165         unsigned char   buf [13];
 166
 167         ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 168         if (ret == 12)
 169                 tmp = hex2bin(dev->net->dev_addr, buf, 6);
 170         if (tmp < 0) {
 171                 dev_dbg(&dev->udev->dev,
 172                         "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 173                 if (ret >= 0)
 174                         ret = -EINVAL;
 175                 return ret;
 176         }
 177         return 0;
 178 }
 179 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 180
 181 static void intr_complete (struct urb *urb)
 182 {
 183         struct usbnet   *dev = urb->context;
 184         int             status = urb->status;
 185
 186         switch (status) {
 187         /* success */
 188         case 0:
 189                 dev->driver_info->status(dev, urb);
 190                 break;
 191
 192         /* software-driven interface shutdown */
 193         case -ENOENT:           /* urb killed */
 194         case -ESHUTDOWN:        /* hardware gone */
 195                 netif_dbg(dev, ifdown, dev->net,
 196                           "intr shutdown, code %d\n", status);
 197                 return;
 198
 199         /* NOTE:  not throttling like RX/TX, since this endpoint
 200          * already polls infrequently
 201          */
 202         default:
 203                 netdev_dbg(dev->net, "intr status %d\n", status);
 204                 break;
 205         }
 206
 207         status = usb_submit_urb (urb, GFP_ATOMIC);
 208         if (status != 0)
 209                 netif_err(dev, timer, dev->net,
 210                           "intr resubmit --> %d\n", status);
 211 }
 212
 213 static int init_status (struct usbnet *dev, struct usb_interface *intf)
 214 {
 215         char            *buf = NULL;
 216         unsigned        pipe = 0;
 217         unsigned        maxp;
 218         unsigned        period;
 219
 220         if (!dev->driver_info->status)
 221                 return 0;
 222
 223         pipe = usb_rcvintpipe (dev->udev,
 224                         dev->status->desc.bEndpointAddress
 225                                 & USB_ENDPOINT_NUMBER_MASK);
 226         maxp = usb_maxpacket (dev->udev, pipe, 0);
 227
 228         /* avoid 1 msec chatter:  min 8 msec poll rate */
 229         period = max ((int) dev->status->desc.bInterval,
 230                 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 231
 232         buf = kmalloc (maxp, GFP_KERNEL);
 233         if (buf) {
 234                 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 235                 if (!dev->interrupt) {
 236                         kfree (buf);
 237                         return -ENOMEM;
 238                 } else {
 239                         usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 240                                 buf, maxp, intr_complete, dev, period);
 241                         dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
 242                         dev_dbg(&intf->dev,
 243                                 "status ep%din, %d bytes period %d\n",
 244                                 usb_pipeendpoint(pipe), maxp, period);
 245                 }
 246         }
 247         return 0;
 248 }
 249
 250 /* Submit the interrupt URB if not previously submitted, increasing refcount */
 251 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
 252 {
 253         int ret = 0;
 254
 255         WARN_ON_ONCE(dev->interrupt == NULL);
 256         if (dev->interrupt) {
 257                 mutex_lock(&dev->interrupt_mutex);
 258
 259                 if (++dev->interrupt_count == 1)
 260                         ret = usb_submit_urb(dev->interrupt, mem_flags);
 261
 262                 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
 263                         dev->interrupt_count);
 264                 mutex_unlock(&dev->interrupt_mutex);
 265         }
 266         return ret;
 267 }
 268 EXPORT_SYMBOL_GPL(usbnet_status_start);
 269
 270 /* For resume; submit interrupt URB if previously submitted */
 271 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
 272 {
 273         int ret = 0;
 274
 275         mutex_lock(&dev->interrupt_mutex);
 276         if (dev->interrupt_count) {
 277                 ret = usb_submit_urb(dev->interrupt, mem_flags);
 278                 dev_dbg(&dev->udev->dev,
 279                         "submitted interrupt URB for resume\n");
 280         }
 281         mutex_unlock(&dev->interrupt_mutex);
 282         return ret;
 283 }
 284
 285 /* Kill the interrupt URB if all submitters want it killed */
 286 void usbnet_status_stop(struct usbnet *dev)
 287 {
 288         if (dev->interrupt) {
 289                 mutex_lock(&dev->interrupt_mutex);
 290                 WARN_ON(dev->interrupt_count == 0);
 291
 292                 if (dev->interrupt_count && --dev->interrupt_count == 0)
 293                         usb_kill_urb(dev->interrupt);
 294
 295                 dev_dbg(&dev->udev->dev,
 296                         "decremented interrupt URB count to %d\n",
 297                         dev->interrupt_count);
 298                 mutex_unlock(&dev->interrupt_mutex);
 299         }
 300 }
 301 EXPORT_SYMBOL_GPL(usbnet_status_stop);
 302
 303 /* For suspend; always kill interrupt URB */
 304 static void __usbnet_status_stop_force(struct usbnet *dev)
 305 {
 306         if (dev->interrupt) {
 307                 mutex_lock(&dev->interrupt_mutex);
 308                 usb_kill_urb(dev->interrupt);
 309                 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
 310                 mutex_unlock(&dev->interrupt_mutex);
 311         }
 312 }
 313
 314 /* Passes this packet up the stack, updating its accounting.
 315  * Some link protocols batch packets, so their rx_fixup paths
 316  * can return clones as well as just modify the original skb.
 317  */
 318 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 319 {
 320         int     status;
 321
 322         if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 323                 skb_queue_tail(&dev->rxq_pause, skb);
 324                 return;
 325         }
 326
 327         /* only update if unset to allow minidriver rx_fixup override */
 328         if (skb->protocol == 0)
 329                 skb->protocol = eth_type_trans (skb, dev->net);
 330
 331         dev->net->stats.rx_packets++;
 332         dev->net->stats.rx_bytes += skb->len;
 333
 334         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 335                   skb->len + sizeof (struct ethhdr), skb->protocol);
 336         memset (skb->cb, 0, sizeof (struct skb_data));
 337
 338         if (skb_defer_rx_timestamp(skb))
 339                 return;
 340
 341         status = netif_rx (skb);
 342         if (status != NET_RX_SUCCESS)
 343                 netif_dbg(dev, rx_err, dev->net,
 344                           "netif_rx status %d\n", status);
 345 }
 346 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 347
 348 /* must be called if hard_mtu or rx_urb_size changed */
 349 void usbnet_update_max_qlen(struct usbnet *dev)
 350 {
 351         enum usb_device_speed speed = dev->udev->speed;
 352
 353         switch (speed) {
 354         case USB_SPEED_HIGH:
 355                 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
 356                 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
 357                 break;
 358         case USB_SPEED_SUPER:
 359         case USB_SPEED_SUPER_PLUS:
 360                 /*
 361                  * Not take default 5ms qlen for super speed HC to
 362                  * save memory, and iperf tests show 2.5ms qlen can
 363                  * work well
 364                  */
 365                 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
 366                 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
 367                 break;
 368         default:
 369                 dev->rx_qlen = dev->tx_qlen = 4;
 370         }
 371 }
 372 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
 373
 374 \f
 375 /*-------------------------------------------------------------------------
 376  *
 377  * Network Device Driver (peer link to "Host Device", from USB host)
 378  *
 379  *-------------------------------------------------------------------------*/
 380
 381 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 382 {
 383         struct usbnet   *dev = netdev_priv(net);
 384         int             ll_mtu = new_mtu + net->hard_header_len;
 385         int             old_hard_mtu = dev->hard_mtu;
 386         int             old_rx_urb_size = dev->rx_urb_size;
 387
 388         if (new_mtu <= 0)
 389                 return -EINVAL;
 390         // no second zero-length packet read wanted after mtu-sized packets
 391         if ((ll_mtu % dev->maxpacket) == 0)
 392                 return -EDOM;
 393         net->mtu = new_mtu;
 394
 395         dev->hard_mtu = net->mtu + net->hard_header_len;
 396         if (dev->rx_urb_size == old_hard_mtu) {
 397                 dev->rx_urb_size = dev->hard_mtu;
 398                 if (dev->rx_urb_size > old_rx_urb_size)
 399                         usbnet_unlink_rx_urbs(dev);
 400         }
 401
 402         /* max qlen depend on hard_mtu and rx_urb_size */
 403         usbnet_update_max_qlen(dev);
 404
 405         return 0;
 406 }
 407 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 408
 409 /* The caller must hold list->lock */
 410 static void __usbnet_queue_skb(struct sk_buff_head *list,
 411                         struct sk_buff *newsk, enum skb_state state)
 412 {
 413         struct skb_data *entry = (struct skb_data *) newsk->cb;
 414
 415         __skb_queue_tail(list, newsk);
 416         entry->state = state;
 417 }
 418
 419 /*-------------------------------------------------------------------------*/
 420
 421 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 422  * completion callbacks.  2.5 should have fixed those bugs...
 423  */
 424
 425 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
 426                 struct sk_buff_head *list, enum skb_state state)
 427 {
 428         unsigned long           flags;
 429         enum skb_state          old_state;
 430         struct skb_data *entry = (struct skb_data *) skb->cb;
 431
 432         spin_lock_irqsave(&list->lock, flags);
 433         old_state = entry->state;
 434         entry->state = state;
 435         __skb_unlink(skb, list);
 436
 437         /* defer_bh() is never called with list == &dev->done.
 438          * spin_lock_nested() tells lockdep that it is OK to take
 439          * dev->done.lock here with list->lock held.
 440          */
 441         spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
 442
 443         __skb_queue_tail(&dev->done, skb);
 444         if (dev->done.qlen == 1)
 445                 tasklet_schedule(&dev->bh);
 446         spin_unlock(&dev->done.lock);
 447         spin_unlock_irqrestore(&list->lock, flags);
 448         return old_state;
 449 }
 450
 451 /* some work can't be done in tasklets, so we use keventd
 452  *
 453  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 454  * but tasklet_schedule() doesn't.  hope the failure is rare.
 455  */
 456 void usbnet_defer_kevent (struct usbnet *dev, int work)
 457 {
 458         set_bit (work, &dev->flags);
 459         if (!schedule_work (&dev->kevent)) {
 460                 if (net_ratelimit())
 461                         netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 462         } else {
 463                 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 464         }
 465 }
 466 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 467
 468 /*-------------------------------------------------------------------------*/
 469
 470 static void rx_complete (struct urb *urb);
 471
 472 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 473 {
 474         struct sk_buff          *skb;
 475         struct skb_data         *entry;
 476         int                     retval = 0;
 477         unsigned long           lockflags;
 478         size_t                  size = dev->rx_urb_size;
 479
 480         /* prevent rx skb allocation when error ratio is high */
 481         if (test_bit(EVENT_RX_KILL, &dev->flags)) {
 482                 usb_free_urb(urb);
 483                 return -ENOLINK;
 484         }
 485
 486         skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
 487         if (!skb) {
 488                 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 489                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 490                 usb_free_urb (urb);
 491                 return -ENOMEM;
 492         }
 493
 494         entry = (struct skb_data *) skb->cb;
 495         entry->urb = urb;
 496         entry->dev = dev;
 497         entry->length = 0;
 498
 499         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 500                 skb->data, size, rx_complete, skb);
 501
 502         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 503
 504         if (netif_running (dev->net) &&
 505             netif_device_present (dev->net) &&
 506             !test_bit (EVENT_RX_HALT, &dev->flags) &&
 507             !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 508                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 509                 case -EPIPE:
 510                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 511                         break;
 512                 case -ENOMEM:
 513                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 514                         break;
 515                 case -ENODEV:
 516                         netif_dbg(dev, ifdown, dev->net, "device gone\n");
 517                         netif_device_detach (dev->net);
 518                         break;
 519                 case -EHOSTUNREACH:
 520                         retval = -ENOLINK;
 521                         break;
 522                 default:
 523                         netif_dbg(dev, rx_err, dev->net,
 524                                   "rx submit, %d\n", retval);
 525                         tasklet_schedule (&dev->bh);
 526                         break;
 527                 case 0:
 528                         __usbnet_queue_skb(&dev->rxq, skb, rx_start);
 529                 }
 530         } else {
 531                 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 532                 retval = -ENOLINK;
 533         }
 534         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 535         if (retval) {
 536                 dev_kfree_skb_any (skb);
 537                 usb_free_urb (urb);
 538         }
 539         return retval;
 540 }
 541
 542
 543 /*-------------------------------------------------------------------------*/
 544
 545 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 546 {
 547         if (dev->driver_info->rx_fixup &&
 548             !dev->driver_info->rx_fixup (dev, skb)) {
 549                 /* With RX_ASSEMBLE, rx_fixup() must update counters */
 550                 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
 551                         dev->net->stats.rx_errors++;
 552                 goto done;
 553         }
 554         // else network stack removes extra byte if we forced a short packet
 555
 556         /* all data was already cloned from skb inside the driver */
 557         if (dev->driver_info->flags & FLAG_MULTI_PACKET)
 558                 goto done;
 559
 560         if (skb->len < ETH_HLEN) {
 561                 dev->net->stats.rx_errors++;
 562                 dev->net->stats.rx_length_errors++;
 563                 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
 564         } else {
 565                 usbnet_skb_return(dev, skb);
 566                 return;
 567         }
 568
 569 done:
 570         skb_queue_tail(&dev->done, skb);
 571 }
 572
 573 /*-------------------------------------------------------------------------*/
 574
 575 static void rx_complete (struct urb *urb)
 576 {
 577         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 578         struct skb_data         *entry = (struct skb_data *) skb->cb;
 579         struct usbnet           *dev = entry->dev;
 580         int                     urb_status = urb->status;
 581         enum skb_state          state;
 582
 583         skb_put (skb, urb->actual_length);
 584         state = rx_done;
 585         entry->urb = NULL;
 586
 587         switch (urb_status) {
 588         /* success */
 589         case 0:
 590                 break;
 591
 592         /* stalls need manual reset. this is rare ... except that
 593          * when going through USB 2.0 TTs, unplug appears this way.
 594          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 595          * storm, recovering as needed.
 596          */
 597         case -EPIPE:
 598                 dev->net->stats.rx_errors++;
 599                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 600                 // FALLTHROUGH
 601
 602         /* software-driven interface shutdown */
 603         case -ECONNRESET:               /* async unlink */
 604         case -ESHUTDOWN:                /* hardware gone */
 605                 netif_dbg(dev, ifdown, dev->net,
 606                           "rx shutdown, code %d\n", urb_status);
 607                 goto block;
 608
 609         /* we get controller i/o faults during hub_wq disconnect() delays.
 610          * throttle down resubmits, to avoid log floods; just temporarily,
 611          * so we still recover when the fault isn't a hub_wq delay.
 612          */
 613         case -EPROTO:
 614         case -ETIME:
 615         case -EILSEQ:
 616                 dev->net->stats.rx_errors++;
 617                 if (!timer_pending (&dev->delay)) {
 618                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 619                         netif_dbg(dev, link, dev->net,
 620                                   "rx throttle %d\n", urb_status);
 621                 }
 622 block:
 623                 state = rx_cleanup;
 624                 entry->urb = urb;
 625                 urb = NULL;
 626                 break;
 627
 628         /* data overrun ... flush fifo? */
 629         case -EOVERFLOW:
 630                 dev->net->stats.rx_over_errors++;
 631                 // FALLTHROUGH
 632
 633         default:
 634                 state = rx_cleanup;
 635                 dev->net->stats.rx_errors++;
 636                 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 637                 break;
 638         }
 639
 640         /* stop rx if packet error rate is high */
 641         if (++dev->pkt_cnt > 30) {
 642                 dev->pkt_cnt = 0;
 643                 dev->pkt_err = 0;
 644         } else {
 645                 if (state == rx_cleanup)
 646                         dev->pkt_err++;
 647                 if (dev->pkt_err > 20)
 648                         set_bit(EVENT_RX_KILL, &dev->flags);
 649         }
 650
 651         state = defer_bh(dev, skb, &dev->rxq, state);
 652
 653         if (urb) {
 654                 if (netif_running (dev->net) &&
 655                     !test_bit (EVENT_RX_HALT, &dev->flags) &&
 656                     state != unlink_start) {
 657                         rx_submit (dev, urb, GFP_ATOMIC);
 658                         usb_mark_last_busy(dev->udev);
 659                         return;
 660                 }
 661                 usb_free_urb (urb);
 662         }
 663         netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 664 }
 665
 666 /*-------------------------------------------------------------------------*/
 667 void usbnet_pause_rx(struct usbnet *dev)
 668 {
 669         set_bit(EVENT_RX_PAUSED, &dev->flags);
 670
 671         netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 672 }
 673 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 674
 675 void usbnet_resume_rx(struct usbnet *dev)
 676 {
 677         struct sk_buff *skb;
 678         int num = 0;
 679
 680         clear_bit(EVENT_RX_PAUSED, &dev->flags);
 681
 682         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 683                 usbnet_skb_return(dev, skb);
 684                 num++;
 685         }
 686
 687         tasklet_schedule(&dev->bh);
 688
 689         netif_dbg(dev, rx_status, dev->net,
 690                   "paused rx queue disabled, %d skbs requeued\n", num);
 691 }
 692 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 693
 694 void usbnet_purge_paused_rxq(struct usbnet *dev)
 695 {
 696         skb_queue_purge(&dev->rxq_pause);
 697 }
 698 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 699
 700 /*-------------------------------------------------------------------------*/
 701
 702 // unlink pending rx/tx; completion handlers do all other cleanup
 703
 704 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 705 {
 706         unsigned long           flags;
 707         struct sk_buff          *skb;
 708         int                     count = 0;
 709
 710         spin_lock_irqsave (&q->lock, flags);
 711         while (!skb_queue_empty(q)) {
 712                 struct skb_data         *entry;
 713                 struct urb              *urb;
 714                 int                     retval;
 715
 716                 skb_queue_walk(q, skb) {
 717                         entry = (struct skb_data *) skb->cb;
 718                         if (entry->state != unlink_start)
 719                                 goto found;
 720                 }
 721                 break;
 722 found:
 723                 entry->state = unlink_start;
 724                 urb = entry->urb;
 725
 726                 /*
 727                  * Get reference count of the URB to avoid it to be
 728                  * freed during usb_unlink_urb, which may trigger
 729                  * use-after-free problem inside usb_unlink_urb since
 730                  * usb_unlink_urb is always racing with .complete
 731                  * handler(include defer_bh).
 732                  */
 733                 usb_get_urb(urb);
 734                 spin_unlock_irqrestore(&q->lock, flags);
 735                 // during some PM-driven resume scenarios,
 736                 // these (async) unlinks complete immediately
 737                 retval = usb_unlink_urb (urb);
 738                 if (retval != -EINPROGRESS && retval != 0)
 739                         netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 740                 else
 741                         count++;
 742                 usb_put_urb(urb);
 743                 spin_lock_irqsave(&q->lock, flags);
 744         }
 745         spin_unlock_irqrestore (&q->lock, flags);
 746         return count;
 747 }
 748
 749 // Flush all pending rx urbs
 750 // minidrivers may need to do this when the MTU changes
 751
 752 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 753 {
 754         if (netif_running(dev->net)) {
 755                 (void) unlink_urbs (dev, &dev->rxq);
 756                 tasklet_schedule(&dev->bh);
 757         }
 758 }
 759 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 760
 761 /*-------------------------------------------------------------------------*/
 762
 763 static void wait_skb_queue_empty(struct sk_buff_head *q)
 764 {
 765         unsigned long flags;
 766
 767         spin_lock_irqsave(&q->lock, flags);
 768         while (!skb_queue_empty(q)) {
 769                 spin_unlock_irqrestore(&q->lock, flags);
 770                 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 771                 set_current_state(TASK_UNINTERRUPTIBLE);
 772                 spin_lock_irqsave(&q->lock, flags);
 773         }
 774         spin_unlock_irqrestore(&q->lock, flags);
 775 }
 776
 777 // precondition: never called in_interrupt
 778 static void usbnet_terminate_urbs(struct usbnet *dev)
 779 {
 780         DECLARE_WAITQUEUE(wait, current);
 781         int temp;
 782
 783         /* ensure there are no more active urbs */
 784         add_wait_queue(&dev->wait, &wait);
 785         set_current_state(TASK_UNINTERRUPTIBLE);
 786         temp = unlink_urbs(dev, &dev->txq) +
 787                 unlink_urbs(dev, &dev->rxq);
 788
 789         /* maybe wait for deletions to finish. */
 790         wait_skb_queue_empty(&dev->rxq);
 791         wait_skb_queue_empty(&dev->txq);
 792         wait_skb_queue_empty(&dev->done);
 793         netif_dbg(dev, ifdown, dev->net,
 794                   "waited for %d urb completions\n", temp);
 795         set_current_state(TASK_RUNNING);
 796         remove_wait_queue(&dev->wait, &wait);
 797 }
 798
 799 int usbnet_stop (struct net_device *net)
 800 {
 801         struct usbnet           *dev = netdev_priv(net);
 802         struct driver_info      *info = dev->driver_info;
 803         int                     retval, pm, mpn;
 804
 805         clear_bit(EVENT_DEV_OPEN, &dev->flags);
 806         netif_stop_queue (net);
 807
 808         netif_info(dev, ifdown, dev->net,
 809                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 810                    net->stats.rx_packets, net->stats.tx_packets,
 811                    net->stats.rx_errors, net->stats.tx_errors);
 812
 813         /* to not race resume */
 814         pm = usb_autopm_get_interface(dev->intf);
 815         /* allow minidriver to stop correctly (wireless devices to turn off
 816          * radio etc) */
 817         if (info->stop) {
 818                 retval = info->stop(dev);
 819                 if (retval < 0)
 820                         netif_info(dev, ifdown, dev->net,
 821                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
 822                                    retval,
 823                                    dev->udev->bus->bus_name, dev->udev->devpath,
 824                                    info->description);
 825         }
 826
 827         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 828                 usbnet_terminate_urbs(dev);
 829
 830         usbnet_status_stop(dev);
 831
 832         usbnet_purge_paused_rxq(dev);
 833
 834         mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
 835
 836         /* deferred work (task, timer, softirq) must also stop.
 837          * can't flush_scheduled_work() until we drop rtnl (later),
 838          * else workers could deadlock; so make workers a NOP.
 839          */
 840         dev->flags = 0;
 841         del_timer_sync (&dev->delay);
 842         tasklet_kill (&dev->bh);
 843         if (!pm)
 844                 usb_autopm_put_interface(dev->intf);
 845
 846         if (info->manage_power && mpn)
 847                 info->manage_power(dev, 0);
 848         else
 849                 usb_autopm_put_interface(dev->intf);
 850
 851         return 0;
 852 }
 853 EXPORT_SYMBOL_GPL(usbnet_stop);
 854
 855 /*-------------------------------------------------------------------------*/
 856
 857 // posts reads, and enables write queuing
 858
 859 // precondition: never called in_interrupt
 860
 861 int usbnet_open (struct net_device *net)
 862 {
 863         struct usbnet           *dev = netdev_priv(net);
 864         int                     retval;
 865         struct driver_info      *info = dev->driver_info;
 866
 867         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 868                 netif_info(dev, ifup, dev->net,
 869                            "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 870                            retval,
 871                            dev->udev->bus->bus_name,
 872                            dev->udev->devpath,
 873                            info->description);
 874                 goto done_nopm;
 875         }
 876
 877         // put into "known safe" state
 878         if (info->reset && (retval = info->reset (dev)) < 0) {
 879                 netif_info(dev, ifup, dev->net,
 880                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 881                            retval,
 882                            dev->udev->bus->bus_name,
 883                            dev->udev->devpath,
 884                            info->description);
 885                 goto done;
 886         }
 887
 888         /* hard_mtu or rx_urb_size may change in reset() */
 889         usbnet_update_max_qlen(dev);
 890
 891         // insist peer be connected
 892         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 893                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 894                 goto done;
 895         }
 896
 897         /* start any status interrupt transfer */
 898         if (dev->interrupt) {
 899                 retval = usbnet_status_start(dev, GFP_KERNEL);
 900                 if (retval < 0) {
 901                         netif_err(dev, ifup, dev->net,
 902                                   "intr submit %d\n", retval);
 903                         goto done;
 904                 }
 905         }
 906
 907         set_bit(EVENT_DEV_OPEN, &dev->flags);
 908         netif_start_queue (net);
 909         netif_info(dev, ifup, dev->net,
 910                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 911                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 912                    dev->net->mtu,
 913                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 914                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 915                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 916                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 917                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 918                    "simple");
 919
 920         /* reset rx error state */
 921         dev->pkt_cnt = 0;
 922         dev->pkt_err = 0;
 923         clear_bit(EVENT_RX_KILL, &dev->flags);
 924
 925         // delay posting reads until we're fully open
 926         tasklet_schedule (&dev->bh);
 927         if (info->manage_power) {
 928                 retval = info->manage_power(dev, 1);
 929                 if (retval < 0) {
 930                         retval = 0;
 931                         set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
 932                 } else {
 933                         usb_autopm_put_interface(dev->intf);
 934                 }
 935         }
 936         return retval;
 937 done:
 938         usb_autopm_put_interface(dev->intf);
 939 done_nopm:
 940         return retval;
 941 }
 942 EXPORT_SYMBOL_GPL(usbnet_open);
 943
 944 /*-------------------------------------------------------------------------*/
 945
 946 /* ethtool methods; minidrivers may need to add some more, but
 947  * they'll probably want to use this base set.
 948  */
 949
 950 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 951 {
 952         struct usbnet *dev = netdev_priv(net);
 953
 954         if (!dev->mii.mdio_read)
 955                 return -EOPNOTSUPP;
 956
 957         return mii_ethtool_gset(&dev->mii, cmd);
 958 }
 959 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 960
 961 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 962 {
 963         struct usbnet *dev = netdev_priv(net);
 964         int retval;
 965
 966         if (!dev->mii.mdio_write)
 967                 return -EOPNOTSUPP;
 968
 969         retval = mii_ethtool_sset(&dev->mii, cmd);
 970
 971         /* link speed/duplex might have changed */
 972         if (dev->driver_info->link_reset)
 973                 dev->driver_info->link_reset(dev);
 974
 975         /* hard_mtu or rx_urb_size may change in link_reset() */
 976         usbnet_update_max_qlen(dev);
 977
 978         return retval;
 979
 980 }
 981 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 982
 983 u32 usbnet_get_link (struct net_device *net)
 984 {
 985         struct usbnet *dev = netdev_priv(net);
 986
 987         /* If a check_connect is defined, return its result */
 988         if (dev->driver_info->check_connect)
 989                 return dev->driver_info->check_connect (dev) == 0;
 990
 991         /* if the device has mii operations, use those */
 992         if (dev->mii.mdio_read)
 993                 return mii_link_ok(&dev->mii);
 994
 995         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 996         return ethtool_op_get_link(net);
 997 }
 998 EXPORT_SYMBOL_GPL(usbnet_get_link);
 999
1000 int usbnet_nway_reset(struct net_device *net)
1001 {
1002         struct usbnet *dev = netdev_priv(net);
1003
1004         if (!dev->mii.mdio_write)
1005                 return -EOPNOTSUPP;
1006
1007         return mii_nway_restart(&dev->mii);
1008 }
1009 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1010
1011 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1012 {
1013         struct usbnet *dev = netdev_priv(net);
1014
1015         strlcpy (info->driver, dev->driver_name, sizeof info->driver);
1016         strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
1017         strlcpy (info->fw_version, dev->driver_info->description,
1018                 sizeof info->fw_version);
1019         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1020 }
1021 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1022
1023 u32 usbnet_get_msglevel (struct net_device *net)
1024 {
1025         struct usbnet *dev = netdev_priv(net);
1026
1027         return dev->msg_enable;
1028 }
1029 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1030
1031 void usbnet_set_msglevel (struct net_device *net, u32 level)
1032 {
1033         struct usbnet *dev = netdev_priv(net);
1034
1035         dev->msg_enable = level;
1036 }
1037 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1038
1039 /* drivers may override default ethtool_ops in their bind() routine */
1040 static const struct ethtool_ops usbnet_ethtool_ops = {
1041         .get_settings           = usbnet_get_settings,
1042         .set_settings           = usbnet_set_settings,
1043         .get_link               = usbnet_get_link,
1044         .nway_reset             = usbnet_nway_reset,
1045         .get_drvinfo            = usbnet_get_drvinfo,
1046         .get_msglevel           = usbnet_get_msglevel,
1047         .set_msglevel           = usbnet_set_msglevel,
1048         .get_ts_info            = ethtool_op_get_ts_info,
1049 };
1050
1051 /*-------------------------------------------------------------------------*/
1052
1053 static void __handle_link_change(struct usbnet *dev)
1054 {
1055         if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1056                 return;
1057
1058         if (!netif_carrier_ok(dev->net)) {
1059                 /* kill URBs for reading packets to save bus bandwidth */
1060                 unlink_urbs(dev, &dev->rxq);
1061
1062                 /*
1063                  * tx_timeout will unlink URBs for sending packets and
1064                  * tx queue is stopped by netcore after link becomes off
1065                  */
1066         } else {
1067                 /* submitting URBs for reading packets */
1068                 tasklet_schedule(&dev->bh);
1069         }
1070
1071         /* hard_mtu or rx_urb_size may change during link change */
1072         usbnet_update_max_qlen(dev);
1073
1074         clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1075 }
1076
1077 static void usbnet_set_rx_mode(struct net_device *net)
1078 {
1079         struct usbnet           *dev = netdev_priv(net);
1080
1081         usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1082 }
1083
1084 static void __handle_set_rx_mode(struct usbnet *dev)
1085 {
1086         if (dev->driver_info->set_rx_mode)
1087                 (dev->driver_info->set_rx_mode)(dev);
1088
1089         clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1090 }
1091
1092 /* work that cannot be done in interrupt context uses keventd.
1093  *
1094  * NOTE:  with 2.5 we could do more of this using completion callbacks,
1095  * especially now that control transfers can be queued.
1096  */
1097 static void
1098 usbnet_deferred_kevent (struct work_struct *work)
1099 {
1100         struct usbnet           *dev =
1101                 container_of(work, struct usbnet, kevent);
1102         int                     status;
1103
1104         /* usb_clear_halt() needs a thread context */
1105         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1106                 unlink_urbs (dev, &dev->txq);
1107                 status = usb_autopm_get_interface(dev->intf);
1108                 if (status < 0)
1109                         goto fail_pipe;
1110                 status = usb_clear_halt (dev->udev, dev->out);
1111                 usb_autopm_put_interface(dev->intf);
1112                 if (status < 0 &&
1113                     status != -EPIPE &&
1114                     status != -ESHUTDOWN) {
1115                         if (netif_msg_tx_err (dev))
1116 fail_pipe:
1117                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1118                                            status);
1119                 } else {
1120                         clear_bit (EVENT_TX_HALT, &dev->flags);
1121                         if (status != -ESHUTDOWN)
1122                                 netif_wake_queue (dev->net);
1123                 }
1124         }
1125         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1126                 unlink_urbs (dev, &dev->rxq);
1127                 status = usb_autopm_get_interface(dev->intf);
1128                 if (status < 0)
1129                         goto fail_halt;
1130                 status = usb_clear_halt (dev->udev, dev->in);
1131                 usb_autopm_put_interface(dev->intf);
1132                 if (status < 0 &&
1133                     status != -EPIPE &&
1134                     status != -ESHUTDOWN) {
1135                         if (netif_msg_rx_err (dev))
1136 fail_halt:
1137                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1138                                            status);
1139                 } else {
1140                         clear_bit (EVENT_RX_HALT, &dev->flags);
1141                         tasklet_schedule (&dev->bh);
1142                 }
1143         }
1144
1145         /* tasklet could resubmit itself forever if memory is tight */
1146         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1147                 struct urb      *urb = NULL;
1148                 int resched = 1;
1149
1150                 if (netif_running (dev->net))
1151                         urb = usb_alloc_urb (0, GFP_KERNEL);
1152                 else
1153                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1154                 if (urb != NULL) {
1155                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1156                         status = usb_autopm_get_interface(dev->intf);
1157                         if (status < 0) {
1158                                 usb_free_urb(urb);
1159                                 goto fail_lowmem;
1160                         }
1161                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1162                                 resched = 0;
1163                         usb_autopm_put_interface(dev->intf);
1164 fail_lowmem:
1165                         if (resched)
1166                                 tasklet_schedule (&dev->bh);
1167                 }
1168         }
1169
1170         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1171                 struct driver_info      *info = dev->driver_info;
1172                 int                     retval = 0;
1173
1174                 clear_bit (EVENT_LINK_RESET, &dev->flags);
1175                 status = usb_autopm_get_interface(dev->intf);
1176                 if (status < 0)
1177                         goto skip_reset;
1178                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1179                         usb_autopm_put_interface(dev->intf);
1180 skip_reset:
1181                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1182                                     retval,
1183                                     dev->udev->bus->bus_name,
1184                                     dev->udev->devpath,
1185                                     info->description);
1186                 } else {
1187                         usb_autopm_put_interface(dev->intf);
1188                 }
1189
1190                 /* handle link change from link resetting */
1191                 __handle_link_change(dev);
1192         }
1193
1194         if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1195                 __handle_link_change(dev);
1196
1197         if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1198                 __handle_set_rx_mode(dev);
1199
1200
1201         if (dev->flags)
1202                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1203 }
1204
1205 /*-------------------------------------------------------------------------*/
1206
1207 static void tx_complete (struct urb *urb)
1208 {
1209         struct sk_buff          *skb = (struct sk_buff *) urb->context;
1210         struct skb_data         *entry = (struct skb_data *) skb->cb;
1211         struct usbnet           *dev = entry->dev;
1212
1213         if (urb->status == 0) {
1214                 dev->net->stats.tx_packets += entry->packets;
1215                 dev->net->stats.tx_bytes += entry->length;
1216         } else {
1217                 dev->net->stats.tx_errors++;
1218
1219                 switch (urb->status) {
1220                 case -EPIPE:
1221                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
1222                         break;
1223
1224                 /* software-driven interface shutdown */
1225                 case -ECONNRESET:               // async unlink
1226                 case -ESHUTDOWN:                // hardware gone
1227                         break;
1228
1229                 /* like rx, tx gets controller i/o faults during hub_wq
1230                  * delays and so it uses the same throttling mechanism.
1231                  */
1232                 case -EPROTO:
1233                 case -ETIME:
1234                 case -EILSEQ:
1235                         usb_mark_last_busy(dev->udev);
1236                         if (!timer_pending (&dev->delay)) {
1237                                 mod_timer (&dev->delay,
1238                                         jiffies + THROTTLE_JIFFIES);
1239                                 netif_dbg(dev, link, dev->net,
1240                                           "tx throttle %d\n", urb->status);
1241                         }
1242                         netif_stop_queue (dev->net);
1243                         break;
1244                 default:
1245                         netif_dbg(dev, tx_err, dev->net,
1246                                   "tx err %d\n", entry->urb->status);
1247                         break;
1248                 }
1249         }
1250
1251         usb_autopm_put_interface_async(dev->intf);
1252         (void) defer_bh(dev, skb, &dev->txq, tx_done);
1253 }
1254
1255 /*-------------------------------------------------------------------------*/
1256
1257 void usbnet_tx_timeout (struct net_device *net)
1258 {
1259         struct usbnet           *dev = netdev_priv(net);
1260
1261         unlink_urbs (dev, &dev->txq);
1262         tasklet_schedule (&dev->bh);
1263         /* this needs to be handled individually because the generic layer
1264          * doesn't know what is sufficient and could not restore private
1265          * information if a remedy of an unconditional reset were used.
1266          */
1267         if (dev->driver_info->recover)
1268                 (dev->driver_info->recover)(dev);
1269 }
1270 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1271
1272 /*-------------------------------------------------------------------------*/
1273
1274 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1275 {
1276         unsigned num_sgs, total_len = 0;
1277         int i, s = 0;
1278
1279         num_sgs = skb_shinfo(skb)->nr_frags + 1;
1280         if (num_sgs == 1)
1281                 return 0;
1282
1283         /* reserve one for zero packet */
1284         urb->sg = kmalloc((num_sgs + 1) * sizeof(struct scatterlist),
1285                           GFP_ATOMIC);
1286         if (!urb->sg)
1287                 return -ENOMEM;
1288
1289         urb->num_sgs = num_sgs;
1290         sg_init_table(urb->sg, urb->num_sgs + 1);
1291
1292         sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1293         total_len += skb_headlen(skb);
1294
1295         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1296                 struct skb_frag_struct *f = &skb_shinfo(skb)->frags[i];
1297
1298                 total_len += skb_frag_size(f);
1299                 sg_set_page(&urb->sg[i + s], f->page.p, f->size,
1300                                 f->page_offset);
1301         }
1302         urb->transfer_buffer_length = total_len;
1303
1304         return 1;
1305 }
1306
1307 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1308                                      struct net_device *net)
1309 {
1310         struct usbnet           *dev = netdev_priv(net);
1311         unsigned int                    length;
1312         struct urb              *urb = NULL;
1313         struct skb_data         *entry;
1314         struct driver_info      *info = dev->driver_info;
1315         unsigned long           flags;
1316         int retval;
1317
1318         if (skb)
1319                 skb_tx_timestamp(skb);
1320
1321         // some devices want funky USB-level framing, for
1322         // win32 driver (usually) and/or hardware quirks
1323         if (info->tx_fixup) {
1324                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1325                 if (!skb) {
1326                         /* packet collected; minidriver waiting for more */
1327                         if (info->flags & FLAG_MULTI_PACKET)
1328                                 goto not_drop;
1329                         netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1330                         goto drop;
1331                 }
1332         }
1333
1334         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1335                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1336                 goto drop;
1337         }
1338
1339         entry = (struct skb_data *) skb->cb;
1340         entry->urb = urb;
1341         entry->dev = dev;
1342
1343         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1344                         skb->data, skb->len, tx_complete, skb);
1345         if (dev->can_dma_sg) {
1346                 if (build_dma_sg(skb, urb) < 0)
1347                         goto drop;
1348         }
1349         length = urb->transfer_buffer_length;
1350
1351         /* don't assume the hardware handles USB_ZERO_PACKET
1352          * NOTE:  strictly conforming cdc-ether devices should expect
1353          * the ZLP here, but ignore the one-byte packet.
1354          * NOTE2: CDC NCM specification is different from CDC ECM when
1355          * handling ZLP/short packets, so cdc_ncm driver will make short
1356          * packet itself if needed.
1357          */
1358         if (length % dev->maxpacket == 0) {
1359                 if (!(info->flags & FLAG_SEND_ZLP)) {
1360                         if (!(info->flags & FLAG_MULTI_PACKET)) {
1361                                 length++;
1362                                 if (skb_tailroom(skb) && !urb->num_sgs) {
1363                                         skb->data[skb->len] = 0;
1364                                         __skb_put(skb, 1);
1365                                 } else if (urb->num_sgs)
1366                                         sg_set_buf(&urb->sg[urb->num_sgs++],
1367                                                         dev->padding_pkt, 1);
1368                         }
1369                 } else
1370                         urb->transfer_flags |= URB_ZERO_PACKET;
1371         }
1372         urb->transfer_buffer_length = length;
1373
1374         if (info->flags & FLAG_MULTI_PACKET) {
1375                 /* Driver has set number of packets and a length delta.
1376                  * Calculate the complete length and ensure that it's
1377                  * positive.
1378                  */
1379                 entry->length += length;
1380                 if (WARN_ON_ONCE(entry->length <= 0))
1381                         entry->length = length;
1382         } else {
1383                 usbnet_set_skb_tx_stats(skb, 1, length);
1384         }
1385
1386         spin_lock_irqsave(&dev->txq.lock, flags);
1387         retval = usb_autopm_get_interface_async(dev->intf);
1388         if (retval < 0) {
1389                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1390                 goto drop;
1391         }
1392
1393 #ifdef CONFIG_PM
1394         /* if this triggers the device is still a sleep */
1395         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1396                 /* transmission will be done in resume */
1397                 usb_anchor_urb(urb, &dev->deferred);
1398                 /* no use to process more packets */
1399                 netif_stop_queue(net);
1400                 usb_put_urb(urb);
1401                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1402                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1403                 goto deferred;
1404         }
1405 #endif
1406
1407         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1408         case -EPIPE:
1409                 netif_stop_queue (net);
1410                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1411                 usb_autopm_put_interface_async(dev->intf);
1412                 break;
1413         default:
1414                 usb_autopm_put_interface_async(dev->intf);
1415                 netif_dbg(dev, tx_err, dev->net,
1416                           "tx: submit urb err %d\n", retval);
1417                 break;
1418         case 0:
1419                 netif_trans_update(net);
1420                 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1421                 if (dev->txq.qlen >= TX_QLEN (dev))
1422                         netif_stop_queue (net);
1423         }
1424         spin_unlock_irqrestore (&dev->txq.lock, flags);
1425
1426         if (retval) {
1427                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1428 drop:
1429                 dev->net->stats.tx_dropped++;
1430 not_drop:
1431                 if (skb)
1432                         dev_kfree_skb_any (skb);
1433                 if (urb) {
1434                         kfree(urb->sg);
1435                         usb_free_urb(urb);
1436                 }
1437         } else
1438                 netif_dbg(dev, tx_queued, dev->net,
1439                           "> tx, len %u, type 0x%x\n", length, skb->protocol);
1440 #ifdef CONFIG_PM
1441 deferred:
1442 #endif
1443         return NETDEV_TX_OK;
1444 }
1445 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1446
1447 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1448 {
1449         struct urb      *urb;
1450         int             i;
1451         int             ret = 0;
1452
1453         /* don't refill the queue all at once */
1454         for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1455                 urb = usb_alloc_urb(0, flags);
1456                 if (urb != NULL) {
1457                         ret = rx_submit(dev, urb, flags);
1458                         if (ret)
1459                                 goto err;
1460                 } else {
1461                         ret = -ENOMEM;
1462                         goto err;
1463                 }
1464         }
1465 err:
1466         return ret;
1467 }
1468
1469 /*-------------------------------------------------------------------------*/
1470
1471 // tasklet (work deferred from completions, in_irq) or timer
1472
1473 static void usbnet_bh (unsigned long param)
1474 {
1475         struct usbnet           *dev = (struct usbnet *) param;
1476         struct sk_buff          *skb;
1477         struct skb_data         *entry;
1478
1479         while ((skb = skb_dequeue (&dev->done))) {
1480                 entry = (struct skb_data *) skb->cb;
1481                 switch (entry->state) {
1482                 case rx_done:
1483                         entry->state = rx_cleanup;
1484                         rx_process (dev, skb);
1485                         continue;
1486                 case tx_done:
1487                         kfree(entry->urb->sg);
1488                 case rx_cleanup:
1489                         usb_free_urb (entry->urb);
1490                         dev_kfree_skb (skb);
1491                         continue;
1492                 default:
1493                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1494                 }
1495         }
1496
1497         /* restart RX again after disabling due to high error rate */
1498         clear_bit(EVENT_RX_KILL, &dev->flags);
1499
1500         /* waiting for all pending urbs to complete?
1501          * only then can we forgo submitting anew
1502          */
1503         if (waitqueue_active(&dev->wait)) {
1504                 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1505                         wake_up_all(&dev->wait);
1506
1507         // or are we maybe short a few urbs?
1508         } else if (netif_running (dev->net) &&
1509                    netif_device_present (dev->net) &&
1510                    netif_carrier_ok(dev->net) &&
1511                    !timer_pending (&dev->delay) &&
1512                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1513                 int     temp = dev->rxq.qlen;
1514
1515                 if (temp < RX_QLEN(dev)) {
1516                         if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1517                                 return;
1518                         if (temp != dev->rxq.qlen)
1519                                 netif_dbg(dev, link, dev->net,
1520                                           "rxqlen %d --> %d\n",
1521                                           temp, dev->rxq.qlen);
1522                         if (dev->rxq.qlen < RX_QLEN(dev))
1523                                 tasklet_schedule (&dev->bh);
1524                 }
1525                 if (dev->txq.qlen < TX_QLEN (dev))
1526                         netif_wake_queue (dev->net);
1527         }
1528 }
1529
1530
1531 /*-------------------------------------------------------------------------
1532  *
1533  * USB Device Driver support
1534  *
1535  *-------------------------------------------------------------------------*/
1536
1537 // precondition: never called in_interrupt
1538
1539 void usbnet_disconnect (struct usb_interface *intf)
1540 {
1541         struct usbnet           *dev;
1542         struct usb_device       *xdev;
1543         struct net_device       *net;
1544
1545         dev = usb_get_intfdata(intf);
1546         usb_set_intfdata(intf, NULL);
1547         if (!dev)
1548                 return;
1549
1550         xdev = interface_to_usbdev (intf);
1551
1552         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1553                    intf->dev.driver->name,
1554                    xdev->bus->bus_name, xdev->devpath,
1555                    dev->driver_info->description);
1556
1557         net = dev->net;
1558         unregister_netdev (net);
1559
1560         cancel_work_sync(&dev->kevent);
1561
1562         usb_scuttle_anchored_urbs(&dev->deferred);
1563
1564         if (dev->driver_info->unbind)
1565                 dev->driver_info->unbind (dev, intf);
1566
1567         usb_kill_urb(dev->interrupt);
1568         usb_free_urb(dev->interrupt);
1569         kfree(dev->padding_pkt);
1570
1571         free_netdev(net);
1572 }
1573 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1574
1575 static const struct net_device_ops usbnet_netdev_ops = {
1576         .ndo_open               = usbnet_open,
1577         .ndo_stop               = usbnet_stop,
1578         .ndo_start_xmit         = usbnet_start_xmit,
1579         .ndo_tx_timeout         = usbnet_tx_timeout,
1580         .ndo_set_rx_mode        = usbnet_set_rx_mode,
1581         .ndo_change_mtu         = usbnet_change_mtu,
1582         .ndo_set_mac_address    = eth_mac_addr,
1583         .ndo_validate_addr      = eth_validate_addr,
1584 };
1585
1586 /*-------------------------------------------------------------------------*/
1587
1588 // precondition: never called in_interrupt
1589
1590 static struct device_type wlan_type = {
1591         .name   = "wlan",
1592 };
1593
1594 static struct device_type wwan_type = {
1595         .name   = "wwan",
1596 };
1597
1598 int
1599 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1600 {
1601         struct usbnet                   *dev;
1602         struct net_device               *net;
1603         struct usb_host_interface       *interface;
1604         struct driver_info              *info;
1605         struct usb_device               *xdev;
1606         int                             status;
1607         const char                      *name;
1608         struct usb_driver       *driver = to_usb_driver(udev->dev.driver);
1609
1610         /* usbnet already took usb runtime pm, so have to enable the feature
1611          * for usb interface, otherwise usb_autopm_get_interface may return
1612          * failure if RUNTIME_PM is enabled.
1613          */
1614         if (!driver->supports_autosuspend) {
1615                 driver->supports_autosuspend = 1;
1616                 pm_runtime_enable(&udev->dev);
1617         }
1618
1619         name = udev->dev.driver->name;
1620         info = (struct driver_info *) prod->driver_info;
1621         if (!info) {
1622                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1623                 return -ENODEV;
1624         }
1625         xdev = interface_to_usbdev (udev);
1626         interface = udev->cur_altsetting;
1627
1628         status = -ENOMEM;
1629
1630         // set up our own records
1631         net = alloc_etherdev(sizeof(*dev));
1632         if (!net)
1633                 goto out;
1634
1635         /* netdev_printk() needs this so do it as early as possible */
1636         SET_NETDEV_DEV(net, &udev->dev);
1637
1638         dev = netdev_priv(net);
1639         dev->udev = xdev;
1640         dev->intf = udev;
1641         dev->driver_info = info;
1642         dev->driver_name = name;
1643         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1644                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1645         init_waitqueue_head(&dev->wait);
1646         skb_queue_head_init (&dev->rxq);
1647         skb_queue_head_init (&dev->txq);
1648         skb_queue_head_init (&dev->done);
1649         skb_queue_head_init(&dev->rxq_pause);
1650         dev->bh.func = usbnet_bh;
1651         dev->bh.data = (unsigned long) dev;
1652         INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1653         init_usb_anchor(&dev->deferred);
1654         dev->delay.function = usbnet_bh;
1655         dev->delay.data = (unsigned long) dev;
1656         init_timer (&dev->delay);
1657         mutex_init (&dev->phy_mutex);
1658         mutex_init(&dev->interrupt_mutex);
1659         dev->interrupt_count = 0;
1660
1661         dev->net = net;
1662         strcpy (net->name, "usb%d");
1663         memcpy (net->dev_addr, node_id, sizeof node_id);
1664
1665         /* rx and tx sides can use different message sizes;
1666          * bind() should set rx_urb_size in that case.
1667          */
1668         dev->hard_mtu = net->mtu + net->hard_header_len;
1669
1670         net->netdev_ops = &usbnet_netdev_ops;
1671         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1672         net->ethtool_ops = &usbnet_ethtool_ops;
1673
1674         // allow device-specific bind/init procedures
1675         // NOTE net->name still not usable ...
1676         if (info->bind) {
1677                 status = info->bind (dev, udev);
1678                 if (status < 0)
1679                         goto out1;
1680
1681                 // heuristic:  "usb%d" for links we know are two-host,
1682                 // else "eth%d" when there's reasonable doubt.  userspace
1683                 // can rename the link if it knows better.
1684                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1685                     ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1686                      (net->dev_addr [0] & 0x02) == 0))
1687                         strcpy (net->name, "eth%d");
1688                 /* WLAN devices should always be named "wlan%d" */
1689                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1690                         strcpy(net->name, "wlan%d");
1691                 /* WWAN devices should always be named "wwan%d" */
1692                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1693                         strcpy(net->name, "wwan%d");
1694
1695                 /* devices that cannot do ARP */
1696                 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1697                         net->flags |= IFF_NOARP;
1698
1699                 /* maybe the remote can't receive an Ethernet MTU */
1700                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1701                         net->mtu = dev->hard_mtu - net->hard_header_len;
1702         } else if (!info->in || !info->out)
1703                 status = usbnet_get_endpoints (dev, udev);
1704         else {
1705                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1706                 dev->out = usb_sndbulkpipe (xdev, info->out);
1707                 if (!(info->flags & FLAG_NO_SETINT))
1708                         status = usb_set_interface (xdev,
1709                                 interface->desc.bInterfaceNumber,
1710                                 interface->desc.bAlternateSetting);
1711                 else
1712                         status = 0;
1713
1714         }
1715         if (status >= 0 && dev->status)
1716                 status = init_status (dev, udev);
1717         if (status < 0)
1718                 goto out3;
1719
1720         if (!dev->rx_urb_size)
1721                 dev->rx_urb_size = dev->hard_mtu;
1722         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1723
1724         /* let userspace know we have a random address */
1725         if (ether_addr_equal(net->dev_addr, node_id))
1726                 net->addr_assign_type = NET_ADDR_RANDOM;
1727
1728         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1729                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1730         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1731                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1732
1733         /* initialize max rx_qlen and tx_qlen */
1734         usbnet_update_max_qlen(dev);
1735
1736         if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1737                 !(info->flags & FLAG_MULTI_PACKET)) {
1738                 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1739                 if (!dev->padding_pkt) {
1740                         status = -ENOMEM;
1741                         goto out4;
1742                 }
1743         }
1744
1745         status = register_netdev (net);
1746         if (status)
1747                 goto out5;
1748         netif_info(dev, probe, dev->net,
1749                    "register '%s' at usb-%s-%s, %s, %pM\n",
1750                    udev->dev.driver->name,
1751                    xdev->bus->bus_name, xdev->devpath,
1752                    dev->driver_info->description,
1753                    net->dev_addr);
1754
1755         // ok, it's ready to go.
1756         usb_set_intfdata (udev, dev);
1757
1758         netif_device_attach (net);
1759
1760         if (dev->driver_info->flags & FLAG_LINK_INTR)
1761                 usbnet_link_change(dev, 0, 0);
1762
1763         return 0;
1764
1765 out5:
1766         kfree(dev->padding_pkt);
1767 out4:
1768         usb_free_urb(dev->interrupt);
1769 out3:
1770         if (info->unbind)
1771                 info->unbind (dev, udev);
1772 out1:
1773         /* subdrivers must undo all they did in bind() if they
1774          * fail it, but we may fail later and a deferred kevent
1775          * may trigger an error resubmitting itself and, worse,
1776          * schedule a timer. So we kill it all just in case.
1777          */
1778         cancel_work_sync(&dev->kevent);
1779         del_timer_sync(&dev->delay);
1780         free_netdev(net);
1781 out:
1782         return status;
1783 }
1784 EXPORT_SYMBOL_GPL(usbnet_probe);
1785
1786 /*-------------------------------------------------------------------------*/
1787
1788 /*
1789  * suspend the whole driver as soon as the first interface is suspended
1790  * resume only when the last interface is resumed
1791  */
1792
1793 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1794 {
1795         struct usbnet           *dev = usb_get_intfdata(intf);
1796
1797         if (!dev->suspend_count++) {
1798                 spin_lock_irq(&dev->txq.lock);
1799                 /* don't autosuspend while transmitting */
1800                 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1801                         dev->suspend_count--;
1802                         spin_unlock_irq(&dev->txq.lock);
1803                         return -EBUSY;
1804                 } else {
1805                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1806                         spin_unlock_irq(&dev->txq.lock);
1807                 }
1808                 /*
1809                  * accelerate emptying of the rx and queues, to avoid
1810                  * having everything error out.
1811                  */
1812                 netif_device_detach (dev->net);
1813                 usbnet_terminate_urbs(dev);
1814                 __usbnet_status_stop_force(dev);
1815
1816                 /*
1817                  * reattach so runtime management can use and
1818                  * wake the device
1819                  */
1820                 netif_device_attach (dev->net);
1821         }
1822         return 0;
1823 }
1824 EXPORT_SYMBOL_GPL(usbnet_suspend);
1825
1826 int usbnet_resume (struct usb_interface *intf)
1827 {
1828         struct usbnet           *dev = usb_get_intfdata(intf);
1829         struct sk_buff          *skb;
1830         struct urb              *res;
1831         int                     retval;
1832
1833         if (!--dev->suspend_count) {
1834                 /* resume interrupt URB if it was previously submitted */
1835                 __usbnet_status_start_force(dev, GFP_NOIO);
1836
1837                 spin_lock_irq(&dev->txq.lock);
1838                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1839
1840                         skb = (struct sk_buff *)res->context;
1841                         retval = usb_submit_urb(res, GFP_ATOMIC);
1842                         if (retval < 0) {
1843                                 dev_kfree_skb_any(skb);
1844                                 kfree(res->sg);
1845                                 usb_free_urb(res);
1846                                 usb_autopm_put_interface_async(dev->intf);
1847                         } else {
1848                                 netif_trans_update(dev->net);
1849                                 __skb_queue_tail(&dev->txq, skb);
1850                         }
1851                 }
1852
1853                 smp_mb();
1854                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1855                 spin_unlock_irq(&dev->txq.lock);
1856
1857                 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1858                         /* handle remote wakeup ASAP
1859                          * we cannot race against stop
1860                          */
1861                         if (netif_device_present(dev->net) &&
1862                                 !timer_pending(&dev->delay) &&
1863                                 !test_bit(EVENT_RX_HALT, &dev->flags))
1864                                         rx_alloc_submit(dev, GFP_NOIO);
1865
1866                         if (!(dev->txq.qlen >= TX_QLEN(dev)))
1867                                 netif_tx_wake_all_queues(dev->net);
1868                         tasklet_schedule (&dev->bh);
1869                 }
1870         }
1871
1872         if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1873                 usb_autopm_get_interface_no_resume(intf);
1874
1875         return 0;
1876 }
1877 EXPORT_SYMBOL_GPL(usbnet_resume);
1878
1879 /*
1880  * Either a subdriver implements manage_power, then it is assumed to always
1881  * be ready to be suspended or it reports the readiness to be suspended
1882  * explicitly
1883  */
1884 void usbnet_device_suggests_idle(struct usbnet *dev)
1885 {
1886         if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1887                 dev->intf->needs_remote_wakeup = 1;
1888                 usb_autopm_put_interface_async(dev->intf);
1889         }
1890 }
1891 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1892
1893 /*
1894  * For devices that can do without special commands
1895  */
1896 int usbnet_manage_power(struct usbnet *dev, int on)
1897 {
1898         dev->intf->needs_remote_wakeup = on;
1899         return 0;
1900 }
1901 EXPORT_SYMBOL(usbnet_manage_power);
1902
1903 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1904 {
1905         /* update link after link is reseted */
1906         if (link && !need_reset)
1907                 netif_carrier_on(dev->net);
1908         else
1909                 netif_carrier_off(dev->net);
1910
1911         if (need_reset && link)
1912                 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1913         else
1914                 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1915 }
1916 EXPORT_SYMBOL(usbnet_link_change);
1917
1918 /*-------------------------------------------------------------------------*/
1919 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1920                              u16 value, u16 index, void *data, u16 size)
1921 {
1922         void *buf = NULL;
1923         int err = -ENOMEM;
1924
1925         netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
1926                    " value=0x%04x index=0x%04x size=%d\n",
1927                    cmd, reqtype, value, index, size);
1928
1929         if (data) {
1930                 buf = kmalloc(size, GFP_KERNEL);
1931                 if (!buf)
1932                         goto out;
1933         }
1934
1935         err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
1936                               cmd, reqtype, value, index, buf, size,
1937                               USB_CTRL_GET_TIMEOUT);
1938         if (err > 0 && err <= size)
1939                 memcpy(data, buf, err);
1940         kfree(buf);
1941 out:
1942         return err;
1943 }
1944
1945 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1946                               u16 value, u16 index, const void *data,
1947                               u16 size)
1948 {
1949         void *buf = NULL;
1950         int err = -ENOMEM;
1951
1952         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
1953                    " value=0x%04x index=0x%04x size=%d\n",
1954                    cmd, reqtype, value, index, size);
1955
1956         if (data) {
1957                 buf = kmemdup(data, size, GFP_KERNEL);
1958                 if (!buf)
1959                         goto out;
1960         }
1961
1962         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
1963                               cmd, reqtype, value, index, buf, size,
1964                               USB_CTRL_SET_TIMEOUT);
1965         kfree(buf);
1966
1967 out:
1968         return err;
1969 }
1970
1971 int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr,
1972                                 struct usb_interface *intf,
1973                                 u8 *buffer,
1974                                 int buflen)
1975 {
1976         /* duplicates are ignored */
1977         struct usb_cdc_union_desc *union_header = NULL;
1978
1979         /* duplicates are not tolerated */
1980         struct usb_cdc_header_desc *header = NULL;
1981         struct usb_cdc_ether_desc *ether = NULL;
1982         struct usb_cdc_mdlm_detail_desc *detail = NULL;
1983         struct usb_cdc_mdlm_desc *desc = NULL;
1984
1985         unsigned int elength;
1986         int cnt = 0;
1987
1988         memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header));
1989         hdr->phonet_magic_present = false;
1990         while (buflen > 0) {
1991                 elength = buffer[0];
1992                 if (!elength) {
1993                         dev_err(&intf->dev, "skipping garbage byte\n");
1994                         elength = 1;
1995                         goto next_desc;
1996                 }
1997                 if (buffer[1] != USB_DT_CS_INTERFACE) {
1998                         dev_err(&intf->dev, "skipping garbage\n");
1999                         goto next_desc;
2000                 }
2001
2002                 switch (buffer[2]) {
2003                 case USB_CDC_UNION_TYPE: /* we've found it */
2004                         if (elength < sizeof(struct usb_cdc_union_desc))
2005                                 goto next_desc;
2006                         if (union_header) {
2007                                 dev_err(&intf->dev, "More than one union descriptor, skipping ...\n");
2008                                 goto next_desc;
2009                         }
2010                         union_header = (struct usb_cdc_union_desc *)buffer;
2011                         break;
2012                 case USB_CDC_COUNTRY_TYPE:
2013                         if (elength < sizeof(struct usb_cdc_country_functional_desc))
2014                                 goto next_desc;
2015                         hdr->usb_cdc_country_functional_desc =
2016                                 (struct usb_cdc_country_functional_desc *)buffer;
2017                         break;
2018                 case USB_CDC_HEADER_TYPE:
2019                         if (elength != sizeof(struct usb_cdc_header_desc))
2020                                 goto next_desc;
2021                         if (header)
2022                                 return -EINVAL;
2023                         header = (struct usb_cdc_header_desc *)buffer;
2024                         break;
2025                 case USB_CDC_ACM_TYPE:
2026                         if (elength < sizeof(struct usb_cdc_acm_descriptor))
2027                                 goto next_desc;
2028                         hdr->usb_cdc_acm_descriptor =
2029                                 (struct usb_cdc_acm_descriptor *)buffer;
2030                         break;
2031                 case USB_CDC_ETHERNET_TYPE:
2032                         if (elength != sizeof(struct usb_cdc_ether_desc))
2033                                 goto next_desc;
2034                         if (ether)
2035                                 return -EINVAL;
2036                         ether = (struct usb_cdc_ether_desc *)buffer;
2037                         break;
2038                 case USB_CDC_CALL_MANAGEMENT_TYPE:
2039                         if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor))
2040                                 goto next_desc;
2041                         hdr->usb_cdc_call_mgmt_descriptor =
2042                                 (struct usb_cdc_call_mgmt_descriptor *)buffer;
2043                         break;
2044                 case USB_CDC_DMM_TYPE:
2045                         if (elength < sizeof(struct usb_cdc_dmm_desc))
2046                                 goto next_desc;
2047                         hdr->usb_cdc_dmm_desc =
2048                                 (struct usb_cdc_dmm_desc *)buffer;
2049                         break;
2050                 case USB_CDC_MDLM_TYPE:
2051                         if (elength < sizeof(struct usb_cdc_mdlm_desc *))
2052                                 goto next_desc;
2053                         if (desc)
2054                                 return -EINVAL;
2055                         desc = (struct usb_cdc_mdlm_desc *)buffer;
2056                         break;
2057                 case USB_CDC_MDLM_DETAIL_TYPE:
2058                         if (elength < sizeof(struct usb_cdc_mdlm_detail_desc *))
2059                                 goto next_desc;
2060                         if (detail)
2061                                 return -EINVAL;
2062                         detail = (struct usb_cdc_mdlm_detail_desc *)buffer;
2063                         break;
2064                 case USB_CDC_NCM_TYPE:
2065                         if (elength < sizeof(struct usb_cdc_ncm_desc))
2066                                 goto next_desc;
2067                         hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer;
2068                         break;
2069                 case USB_CDC_MBIM_TYPE:
2070                         if (elength < sizeof(struct usb_cdc_mbim_desc))
2071                                 goto next_desc;
2072
2073                         hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer;
2074                         break;
2075                 case USB_CDC_MBIM_EXTENDED_TYPE:
2076                         if (elength < sizeof(struct usb_cdc_mbim_extended_desc))
2077                                 break;
2078                         hdr->usb_cdc_mbim_extended_desc =
2079                                 (struct usb_cdc_mbim_extended_desc *)buffer;
2080                         break;
2081                 case CDC_PHONET_MAGIC_NUMBER:
2082                         hdr->phonet_magic_present = true;
2083                         break;
2084                 default:
2085                         /*
2086                          * there are LOTS more CDC descriptors that
2087                          * could legitimately be found here.
2088                          */
2089                         dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n",
2090                                         buffer[2], elength);
2091                         goto next_desc;
2092                 }
2093                 cnt++;
2094 next_desc:
2095                 buflen -= elength;
2096                 buffer += elength;
2097         }
2098         hdr->usb_cdc_union_desc = union_header;
2099         hdr->usb_cdc_header_desc = header;
2100         hdr->usb_cdc_mdlm_detail_desc = detail;
2101         hdr->usb_cdc_mdlm_desc = desc;
2102         hdr->usb_cdc_ether_desc = ether;
2103         return cnt;
2104 }
2105
2106 EXPORT_SYMBOL(cdc_parse_cdc_header);
2107
2108 /*
2109  * The function can't be called inside suspend/resume callback,
2110  * otherwise deadlock will be caused.
2111  */
2112 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2113                     u16 value, u16 index, void *data, u16 size)
2114 {
2115         int ret;
2116
2117         if (usb_autopm_get_interface(dev->intf) < 0)
2118                 return -ENODEV;
2119         ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2120                                 data, size);
2121         usb_autopm_put_interface(dev->intf);
2122         return ret;
2123 }
2124 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2125
2126 /*
2127  * The function can't be called inside suspend/resume callback,
2128  * otherwise deadlock will be caused.
2129  */
2130 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2131                      u16 value, u16 index, const void *data, u16 size)
2132 {
2133         int ret;
2134
2135         if (usb_autopm_get_interface(dev->intf) < 0)
2136                 return -ENODEV;
2137         ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2138                                  data, size);
2139         usb_autopm_put_interface(dev->intf);
2140         return ret;
2141 }
2142 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2143
2144 /*
2145  * The function can be called inside suspend/resume callback safely
2146  * and should only be called by suspend/resume callback generally.
2147  */
2148 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2149                           u16 value, u16 index, void *data, u16 size)
2150 {
2151         return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2152                                  data, size);
2153 }
2154 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2155
2156 /*
2157  * The function can be called inside suspend/resume callback safely
2158  * and should only be called by suspend/resume callback generally.
2159  */
2160 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2161                           u16 value, u16 index, const void *data,
2162                           u16 size)
2163 {
2164         return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2165                                   data, size);
2166 }
2167 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2168
2169 static void usbnet_async_cmd_cb(struct urb *urb)
2170 {
2171         struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2172         int status = urb->status;
2173
2174         if (status < 0)
2175                 dev_dbg(&urb->dev->dev, "%s failed with %d",
2176                         __func__, status);
2177
2178         kfree(req);
2179         usb_free_urb(urb);
2180 }
2181
2182 /*
2183  * The caller must make sure that device can't be put into suspend
2184  * state until the control URB completes.
2185  */
2186 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2187                            u16 value, u16 index, const void *data, u16 size)
2188 {
2189         struct usb_ctrlrequest *req = NULL;
2190         struct urb *urb;
2191         int err = -ENOMEM;
2192         void *buf = NULL;
2193
2194         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2195                    " value=0x%04x index=0x%04x size=%d\n",
2196                    cmd, reqtype, value, index, size);
2197
2198         urb = usb_alloc_urb(0, GFP_ATOMIC);
2199         if (!urb) {
2200                 netdev_err(dev->net, "Error allocating URB in"
2201                            " %s!\n", __func__);
2202                 goto fail;
2203         }
2204
2205         if (data) {
2206                 buf = kmemdup(data, size, GFP_ATOMIC);
2207                 if (!buf) {
2208                         netdev_err(dev->net, "Error allocating buffer"
2209                                    " in %s!\n", __func__);
2210                         goto fail_free;
2211                 }
2212         }
2213
2214         req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2215         if (!req)
2216                 goto fail_free_buf;
2217
2218         req->bRequestType = reqtype;
2219         req->bRequest = cmd;
2220         req->wValue = cpu_to_le16(value);
2221         req->wIndex = cpu_to_le16(index);
2222         req->wLength = cpu_to_le16(size);
2223
2224         usb_fill_control_urb(urb, dev->udev,
2225                              usb_sndctrlpipe(dev->udev, 0),
2226                              (void *)req, buf, size,
2227                              usbnet_async_cmd_cb, req);
2228         urb->transfer_flags |= URB_FREE_BUFFER;
2229
2230         err = usb_submit_urb(urb, GFP_ATOMIC);
2231         if (err < 0) {
2232                 netdev_err(dev->net, "Error submitting the control"
2233                            " message: status=%d\n", err);
2234                 goto fail_free;
2235         }
2236         return 0;
2237
2238 fail_free_buf:
2239         kfree(buf);
2240 fail_free:
2241         kfree(req);
2242         usb_free_urb(urb);
2243 fail:
2244         return err;
2245
2246 }
2247 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2248 /*-------------------------------------------------------------------------*/
2249
2250 static int __init usbnet_init(void)
2251 {
2252         /* Compiler should optimize this out. */
2253         BUILD_BUG_ON(
2254                 FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
2255
2256         eth_random_addr(node_id);
2257         return 0;
2258 }
2259 module_init(usbnet_init);
2260
2261 static void __exit usbnet_exit(void)
2262 {
2263 }
2264 module_exit(usbnet_exit);
2265
2266 MODULE_AUTHOR("David Brownell");
2267 MODULE_DESCRIPTION("USB network driver framework");
2268 MODULE_LICENSE("GPL");