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/slab.h>
  46 #include <linux/kernel.h>
  47 #include <linux/pm_runtime.h>
  48
  49 #define DRIVER_VERSION          "22-Aug-2005"
  50
  51
  52 /*-------------------------------------------------------------------------*/
  53
  54 /*
  55  * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  56  * Several dozen bytes of IPv4 data can fit in two such transactions.
  57  * One maximum size Ethernet packet takes twenty four of them.
  58  * For high speed, each frame comfortably fits almost 36 max size
  59  * Ethernet packets (so queues should be bigger).
  60  *
  61  * The goal is to let the USB host controller be busy for 5msec or
  62  * more before an irq is required, under load.  Jumbograms change
  63  * the equation.
  64  */
  65 #define MAX_QUEUE_MEMORY        (60 * 1518)
  66 #define RX_QLEN(dev)            ((dev)->rx_qlen)
  67 #define TX_QLEN(dev)            ((dev)->tx_qlen)
  68
  69 // reawaken network queue this soon after stopping; else watchdog barks
  70 #define TX_TIMEOUT_JIFFIES      (5*HZ)
  71
  72 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
  73  * us (it polls at HZ/4 usually) before we report too many false errors.
  74  */
  75 #define THROTTLE_JIFFIES        (HZ/8)
  76
  77 // between wakeups
  78 #define UNLINK_TIMEOUT_MS       3
  79
  80 /*-------------------------------------------------------------------------*/
  81
  82 // randomly generated ethernet address
  83 static u8       node_id [ETH_ALEN];
  84
  85 static const char driver_name [] = "usbnet";
  86
  87 /* use ethtool to change the level for any given device */
  88 static int msg_level = -1;
  89 module_param (msg_level, int, 0);
  90 MODULE_PARM_DESC (msg_level, "Override default message level");
  91
  92 /*-------------------------------------------------------------------------*/
  93
  94 /* handles CDC Ethernet and many other network "bulk data" interfaces */
  95 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  96 {
  97         int                             tmp;
  98         struct usb_host_interface       *alt = NULL;
  99         struct usb_host_endpoint        *in = NULL, *out = NULL;
 100         struct usb_host_endpoint        *status = NULL;
 101
 102         for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 103                 unsigned        ep;
 104
 105                 in = out = status = NULL;
 106                 alt = intf->altsetting + tmp;
 107
 108                 /* take the first altsetting with in-bulk + out-bulk;
 109                  * remember any status endpoint, just in case;
 110                  * ignore other endpoints and altsettings.
 111                  */
 112                 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 113                         struct usb_host_endpoint        *e;
 114                         int                             intr = 0;
 115
 116                         e = alt->endpoint + ep;
 117                         switch (e->desc.bmAttributes) {
 118                         case USB_ENDPOINT_XFER_INT:
 119                                 if (!usb_endpoint_dir_in(&e->desc))
 120                                         continue;
 121                                 intr = 1;
 122                                 /* FALLTHROUGH */
 123                         case USB_ENDPOINT_XFER_BULK:
 124                                 break;
 125                         default:
 126                                 continue;
 127                         }
 128                         if (usb_endpoint_dir_in(&e->desc)) {
 129                                 if (!intr && !in)
 130                                         in = e;
 131                                 else if (intr && !status)
 132                                         status = e;
 133                         } else {
 134                                 if (!out)
 135                                         out = e;
 136                         }
 137                 }
 138                 if (in && out)
 139                         break;
 140         }
 141         if (!alt || !in || !out)
 142                 return -EINVAL;
 143
 144         if (alt->desc.bAlternateSetting != 0 ||
 145             !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 146                 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 147                                 alt->desc.bAlternateSetting);
 148                 if (tmp < 0)
 149                         return tmp;
 150         }
 151
 152         dev->in = usb_rcvbulkpipe (dev->udev,
 153                         in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 154         dev->out = usb_sndbulkpipe (dev->udev,
 155                         out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 156         dev->status = status;
 157         return 0;
 158 }
 159 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 160
 161 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 162 {
 163         int             tmp = -1, ret;
 164         unsigned char   buf [13];
 165
 166         ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 167         if (ret == 12)
 168                 tmp = hex2bin(dev->net->dev_addr, buf, 6);
 169         if (tmp < 0) {
 170                 dev_dbg(&dev->udev->dev,
 171                         "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 172                 if (ret >= 0)
 173                         ret = -EINVAL;
 174                 return ret;
 175         }
 176         return 0;
 177 }
 178 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 179
 180 static void intr_complete (struct urb *urb)
 181 {
 182         struct usbnet   *dev = urb->context;
 183         int             status = urb->status;
 184
 185         switch (status) {
 186         /* success */
 187         case 0:
 188                 dev->driver_info->status(dev, urb);
 189                 break;
 190
 191         /* software-driven interface shutdown */
 192         case -ENOENT:           /* urb killed */
 193         case -ESHUTDOWN:        /* hardware gone */
 194                 netif_dbg(dev, ifdown, dev->net,
 195                           "intr shutdown, code %d\n", status);
 196                 return;
 197
 198         /* NOTE:  not throttling like RX/TX, since this endpoint
 199          * already polls infrequently
 200          */
 201         default:
 202                 netdev_dbg(dev->net, "intr status %d\n", status);
 203                 break;
 204         }
 205
 206         status = usb_submit_urb (urb, GFP_ATOMIC);
 207         if (status != 0)
 208                 netif_err(dev, timer, dev->net,
 209                           "intr resubmit --> %d\n", status);
 210 }
 211
 212 static int init_status (struct usbnet *dev, struct usb_interface *intf)
 213 {
 214         char            *buf = NULL;
 215         unsigned        pipe = 0;
 216         unsigned        maxp;
 217         unsigned        period;
 218
 219         if (!dev->driver_info->status)
 220                 return 0;
 221
 222         pipe = usb_rcvintpipe (dev->udev,
 223                         dev->status->desc.bEndpointAddress
 224                                 & USB_ENDPOINT_NUMBER_MASK);
 225         maxp = usb_maxpacket (dev->udev, pipe, 0);
 226
 227         /* avoid 1 msec chatter:  min 8 msec poll rate */
 228         period = max ((int) dev->status->desc.bInterval,
 229                 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 230
 231         buf = kmalloc (maxp, GFP_KERNEL);
 232         if (buf) {
 233                 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 234                 if (!dev->interrupt) {
 235                         kfree (buf);
 236                         return -ENOMEM;
 237                 } else {
 238                         usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 239                                 buf, maxp, intr_complete, dev, period);
 240                         dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
 241                         dev_dbg(&intf->dev,
 242                                 "status ep%din, %d bytes period %d\n",
 243                                 usb_pipeendpoint(pipe), maxp, period);
 244                 }
 245         }
 246         return 0;
 247 }
 248
 249 /* Submit the interrupt URB if not previously submitted, increasing refcount */
 250 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
 251 {
 252         int ret = 0;
 253
 254         WARN_ON_ONCE(dev->interrupt == NULL);
 255         if (dev->interrupt) {
 256                 mutex_lock(&dev->interrupt_mutex);
 257
 258                 if (++dev->interrupt_count == 1)
 259                         ret = usb_submit_urb(dev->interrupt, mem_flags);
 260
 261                 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
 262                         dev->interrupt_count);
 263                 mutex_unlock(&dev->interrupt_mutex);
 264         }
 265         return ret;
 266 }
 267 EXPORT_SYMBOL_GPL(usbnet_status_start);
 268
 269 /* For resume; submit interrupt URB if previously submitted */
 270 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
 271 {
 272         int ret = 0;
 273
 274         mutex_lock(&dev->interrupt_mutex);
 275         if (dev->interrupt_count) {
 276                 ret = usb_submit_urb(dev->interrupt, mem_flags);
 277                 dev_dbg(&dev->udev->dev,
 278                         "submitted interrupt URB for resume\n");
 279         }
 280         mutex_unlock(&dev->interrupt_mutex);
 281         return ret;
 282 }
 283
 284 /* Kill the interrupt URB if all submitters want it killed */
 285 void usbnet_status_stop(struct usbnet *dev)
 286 {
 287         if (dev->interrupt) {
 288                 mutex_lock(&dev->interrupt_mutex);
 289                 WARN_ON(dev->interrupt_count == 0);
 290
 291                 if (dev->interrupt_count && --dev->interrupt_count == 0)
 292                         usb_kill_urb(dev->interrupt);
 293
 294                 dev_dbg(&dev->udev->dev,
 295                         "decremented interrupt URB count to %d\n",
 296                         dev->interrupt_count);
 297                 mutex_unlock(&dev->interrupt_mutex);
 298         }
 299 }
 300 EXPORT_SYMBOL_GPL(usbnet_status_stop);
 301
 302 /* For suspend; always kill interrupt URB */
 303 static void __usbnet_status_stop_force(struct usbnet *dev)
 304 {
 305         if (dev->interrupt) {
 306                 mutex_lock(&dev->interrupt_mutex);
 307                 usb_kill_urb(dev->interrupt);
 308                 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
 309                 mutex_unlock(&dev->interrupt_mutex);
 310         }
 311 }
 312
 313 /* Passes this packet up the stack, updating its accounting.
 314  * Some link protocols batch packets, so their rx_fixup paths
 315  * can return clones as well as just modify the original skb.
 316  */
 317 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 318 {
 319         int     status;
 320
 321         if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 322                 skb_queue_tail(&dev->rxq_pause, skb);
 323                 return;
 324         }
 325
 326         skb->protocol = eth_type_trans (skb, dev->net);
 327         dev->net->stats.rx_packets++;
 328         dev->net->stats.rx_bytes += skb->len;
 329
 330         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 331                   skb->len + sizeof (struct ethhdr), skb->protocol);
 332         memset (skb->cb, 0, sizeof (struct skb_data));
 333
 334         if (skb_defer_rx_timestamp(skb))
 335                 return;
 336
 337         status = netif_rx (skb);
 338         if (status != NET_RX_SUCCESS)
 339                 netif_dbg(dev, rx_err, dev->net,
 340                           "netif_rx status %d\n", status);
 341 }
 342 EXPORT_SYMBOL_GPL(usbnet_skb_return);
 343
 344 /* must be called if hard_mtu or rx_urb_size changed */
 345 void usbnet_update_max_qlen(struct usbnet *dev)
 346 {
 347         enum usb_device_speed speed = dev->udev->speed;
 348
 349         switch (speed) {
 350         case USB_SPEED_HIGH:
 351                 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
 352                 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
 353                 break;
 354         case USB_SPEED_SUPER:
 355                 /*
 356                  * Not take default 5ms qlen for super speed HC to
 357                  * save memory, and iperf tests show 2.5ms qlen can
 358                  * work well
 359                  */
 360                 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
 361                 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
 362                 break;
 363         default:
 364                 dev->rx_qlen = dev->tx_qlen = 4;
 365         }
 366 }
 367 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
 368
 369 \f
 370 /*-------------------------------------------------------------------------
 371  *
 372  * Network Device Driver (peer link to "Host Device", from USB host)
 373  *
 374  *-------------------------------------------------------------------------*/
 375
 376 int usbnet_change_mtu (struct net_device *net, int new_mtu)
 377 {
 378         struct usbnet   *dev = netdev_priv(net);
 379         int             ll_mtu = new_mtu + net->hard_header_len;
 380         int             old_hard_mtu = dev->hard_mtu;
 381         int             old_rx_urb_size = dev->rx_urb_size;
 382
 383         if (new_mtu <= 0)
 384                 return -EINVAL;
 385         // no second zero-length packet read wanted after mtu-sized packets
 386         if ((ll_mtu % dev->maxpacket) == 0)
 387                 return -EDOM;
 388         net->mtu = new_mtu;
 389
 390         dev->hard_mtu = net->mtu + net->hard_header_len;
 391         if (dev->rx_urb_size == old_hard_mtu) {
 392                 dev->rx_urb_size = dev->hard_mtu;
 393                 if (dev->rx_urb_size > old_rx_urb_size)
 394                         usbnet_unlink_rx_urbs(dev);
 395         }
 396
 397         /* max qlen depend on hard_mtu and rx_urb_size */
 398         usbnet_update_max_qlen(dev);
 399
 400         return 0;
 401 }
 402 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 403
 404 /* The caller must hold list->lock */
 405 static void __usbnet_queue_skb(struct sk_buff_head *list,
 406                         struct sk_buff *newsk, enum skb_state state)
 407 {
 408         struct skb_data *entry = (struct skb_data *) newsk->cb;
 409
 410         __skb_queue_tail(list, newsk);
 411         entry->state = state;
 412 }
 413
 414 /*-------------------------------------------------------------------------*/
 415
 416 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 417  * completion callbacks.  2.5 should have fixed those bugs...
 418  */
 419
 420 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
 421                 struct sk_buff_head *list, enum skb_state state)
 422 {
 423         unsigned long           flags;
 424         enum skb_state          old_state;
 425         struct skb_data *entry = (struct skb_data *) skb->cb;
 426
 427         spin_lock_irqsave(&list->lock, flags);
 428         old_state = entry->state;
 429         entry->state = state;
 430         __skb_unlink(skb, list);
 431
 432         /* defer_bh() is never called with list == &dev->done.
 433          * spin_lock_nested() tells lockdep that it is OK to take
 434          * dev->done.lock here with list->lock held.
 435          */
 436         spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
 437
 438         __skb_queue_tail(&dev->done, skb);
 439         if (dev->done.qlen == 1)
 440                 tasklet_schedule(&dev->bh);
 441         spin_unlock(&dev->done.lock);
 442         spin_unlock_irqrestore(&list->lock, flags);
 443         return old_state;
 444 }
 445
 446 /* some work can't be done in tasklets, so we use keventd
 447  *
 448  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 449  * but tasklet_schedule() doesn't.  hope the failure is rare.
 450  */
 451 void usbnet_defer_kevent (struct usbnet *dev, int work)
 452 {
 453         set_bit (work, &dev->flags);
 454         if (!schedule_work (&dev->kevent)) {
 455                 if (net_ratelimit())
 456                         netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 457         } else {
 458                 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 459         }
 460 }
 461 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 462
 463 /*-------------------------------------------------------------------------*/
 464
 465 static void rx_complete (struct urb *urb);
 466
 467 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 468 {
 469         struct sk_buff          *skb;
 470         struct skb_data         *entry;
 471         int                     retval = 0;
 472         unsigned long           lockflags;
 473         size_t                  size = dev->rx_urb_size;
 474
 475         /* prevent rx skb allocation when error ratio is high */
 476         if (test_bit(EVENT_RX_KILL, &dev->flags)) {
 477                 usb_free_urb(urb);
 478                 return -ENOLINK;
 479         }
 480
 481         skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
 482         if (!skb) {
 483                 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 484                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 485                 usb_free_urb (urb);
 486                 return -ENOMEM;
 487         }
 488
 489         entry = (struct skb_data *) skb->cb;
 490         entry->urb = urb;
 491         entry->dev = dev;
 492         entry->length = 0;
 493
 494         usb_fill_bulk_urb (urb, dev->udev, dev->in,
 495                 skb->data, size, rx_complete, skb);
 496
 497         spin_lock_irqsave (&dev->rxq.lock, lockflags);
 498
 499         if (netif_running (dev->net) &&
 500             netif_device_present (dev->net) &&
 501             !test_bit (EVENT_RX_HALT, &dev->flags) &&
 502             !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 503                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 504                 case -EPIPE:
 505                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
 506                         break;
 507                 case -ENOMEM:
 508                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 509                         break;
 510                 case -ENODEV:
 511                         netif_dbg(dev, ifdown, dev->net, "device gone\n");
 512                         netif_device_detach (dev->net);
 513                         break;
 514                 case -EHOSTUNREACH:
 515                         retval = -ENOLINK;
 516                         break;
 517                 default:
 518                         netif_dbg(dev, rx_err, dev->net,
 519                                   "rx submit, %d\n", retval);
 520                         tasklet_schedule (&dev->bh);
 521                         break;
 522                 case 0:
 523                         __usbnet_queue_skb(&dev->rxq, skb, rx_start);
 524                 }
 525         } else {
 526                 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 527                 retval = -ENOLINK;
 528         }
 529         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 530         if (retval) {
 531                 dev_kfree_skb_any (skb);
 532                 usb_free_urb (urb);
 533         }
 534         return retval;
 535 }
 536
 537
 538 /*-------------------------------------------------------------------------*/
 539
 540 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 541 {
 542         if (dev->driver_info->rx_fixup &&
 543             !dev->driver_info->rx_fixup (dev, skb)) {
 544                 /* With RX_ASSEMBLE, rx_fixup() must update counters */
 545                 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
 546                         dev->net->stats.rx_errors++;
 547                 goto done;
 548         }
 549         // else network stack removes extra byte if we forced a short packet
 550
 551         /* all data was already cloned from skb inside the driver */
 552         if (dev->driver_info->flags & FLAG_MULTI_PACKET)
 553                 goto done;
 554
 555         if (skb->len < ETH_HLEN) {
 556                 dev->net->stats.rx_errors++;
 557                 dev->net->stats.rx_length_errors++;
 558                 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
 559         } else {
 560                 usbnet_skb_return(dev, skb);
 561                 return;
 562         }
 563
 564 done:
 565         skb_queue_tail(&dev->done, skb);
 566 }
 567
 568 /*-------------------------------------------------------------------------*/
 569
 570 static void rx_complete (struct urb *urb)
 571 {
 572         struct sk_buff          *skb = (struct sk_buff *) urb->context;
 573         struct skb_data         *entry = (struct skb_data *) skb->cb;
 574         struct usbnet           *dev = entry->dev;
 575         int                     urb_status = urb->status;
 576         enum skb_state          state;
 577
 578         skb_put (skb, urb->actual_length);
 579         state = rx_done;
 580         entry->urb = NULL;
 581
 582         switch (urb_status) {
 583         /* success */
 584         case 0:
 585                 break;
 586
 587         /* stalls need manual reset. this is rare ... except that
 588          * when going through USB 2.0 TTs, unplug appears this way.
 589          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 590          * storm, recovering as needed.
 591          */
 592         case -EPIPE:
 593                 dev->net->stats.rx_errors++;
 594                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
 595                 // FALLTHROUGH
 596
 597         /* software-driven interface shutdown */
 598         case -ECONNRESET:               /* async unlink */
 599         case -ESHUTDOWN:                /* hardware gone */
 600                 netif_dbg(dev, ifdown, dev->net,
 601                           "rx shutdown, code %d\n", urb_status);
 602                 goto block;
 603
 604         /* we get controller i/o faults during hub_wq disconnect() delays.
 605          * throttle down resubmits, to avoid log floods; just temporarily,
 606          * so we still recover when the fault isn't a hub_wq delay.
 607          */
 608         case -EPROTO:
 609         case -ETIME:
 610         case -EILSEQ:
 611                 dev->net->stats.rx_errors++;
 612                 if (!timer_pending (&dev->delay)) {
 613                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 614                         netif_dbg(dev, link, dev->net,
 615                                   "rx throttle %d\n", urb_status);
 616                 }
 617 block:
 618                 state = rx_cleanup;
 619                 entry->urb = urb;
 620                 urb = NULL;
 621                 break;
 622
 623         /* data overrun ... flush fifo? */
 624         case -EOVERFLOW:
 625                 dev->net->stats.rx_over_errors++;
 626                 // FALLTHROUGH
 627
 628         default:
 629                 state = rx_cleanup;
 630                 dev->net->stats.rx_errors++;
 631                 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 632                 break;
 633         }
 634
 635         /* stop rx if packet error rate is high */
 636         if (++dev->pkt_cnt > 30) {
 637                 dev->pkt_cnt = 0;
 638                 dev->pkt_err = 0;
 639         } else {
 640                 if (state == rx_cleanup)
 641                         dev->pkt_err++;
 642                 if (dev->pkt_err > 20)
 643                         set_bit(EVENT_RX_KILL, &dev->flags);
 644         }
 645
 646         state = defer_bh(dev, skb, &dev->rxq, state);
 647
 648         if (urb) {
 649                 if (netif_running (dev->net) &&
 650                     !test_bit (EVENT_RX_HALT, &dev->flags) &&
 651                     state != unlink_start) {
 652                         rx_submit (dev, urb, GFP_ATOMIC);
 653                         usb_mark_last_busy(dev->udev);
 654                         return;
 655                 }
 656                 usb_free_urb (urb);
 657         }
 658         netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 659 }
 660
 661 /*-------------------------------------------------------------------------*/
 662 void usbnet_pause_rx(struct usbnet *dev)
 663 {
 664         set_bit(EVENT_RX_PAUSED, &dev->flags);
 665
 666         netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 667 }
 668 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 669
 670 void usbnet_resume_rx(struct usbnet *dev)
 671 {
 672         struct sk_buff *skb;
 673         int num = 0;
 674
 675         clear_bit(EVENT_RX_PAUSED, &dev->flags);
 676
 677         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 678                 usbnet_skb_return(dev, skb);
 679                 num++;
 680         }
 681
 682         tasklet_schedule(&dev->bh);
 683
 684         netif_dbg(dev, rx_status, dev->net,
 685                   "paused rx queue disabled, %d skbs requeued\n", num);
 686 }
 687 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 688
 689 void usbnet_purge_paused_rxq(struct usbnet *dev)
 690 {
 691         skb_queue_purge(&dev->rxq_pause);
 692 }
 693 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 694
 695 /*-------------------------------------------------------------------------*/
 696
 697 // unlink pending rx/tx; completion handlers do all other cleanup
 698
 699 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 700 {
 701         unsigned long           flags;
 702         struct sk_buff          *skb;
 703         int                     count = 0;
 704
 705         spin_lock_irqsave (&q->lock, flags);
 706         while (!skb_queue_empty(q)) {
 707                 struct skb_data         *entry;
 708                 struct urb              *urb;
 709                 int                     retval;
 710
 711                 skb_queue_walk(q, skb) {
 712                         entry = (struct skb_data *) skb->cb;
 713                         if (entry->state != unlink_start)
 714                                 goto found;
 715                 }
 716                 break;
 717 found:
 718                 entry->state = unlink_start;
 719                 urb = entry->urb;
 720
 721                 /*
 722                  * Get reference count of the URB to avoid it to be
 723                  * freed during usb_unlink_urb, which may trigger
 724                  * use-after-free problem inside usb_unlink_urb since
 725                  * usb_unlink_urb is always racing with .complete
 726                  * handler(include defer_bh).
 727                  */
 728                 usb_get_urb(urb);
 729                 spin_unlock_irqrestore(&q->lock, flags);
 730                 // during some PM-driven resume scenarios,
 731                 // these (async) unlinks complete immediately
 732                 retval = usb_unlink_urb (urb);
 733                 if (retval != -EINPROGRESS && retval != 0)
 734                         netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 735                 else
 736                         count++;
 737                 usb_put_urb(urb);
 738                 spin_lock_irqsave(&q->lock, flags);
 739         }
 740         spin_unlock_irqrestore (&q->lock, flags);
 741         return count;
 742 }
 743
 744 // Flush all pending rx urbs
 745 // minidrivers may need to do this when the MTU changes
 746
 747 void usbnet_unlink_rx_urbs(struct usbnet *dev)
 748 {
 749         if (netif_running(dev->net)) {
 750                 (void) unlink_urbs (dev, &dev->rxq);
 751                 tasklet_schedule(&dev->bh);
 752         }
 753 }
 754 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 755
 756 /*-------------------------------------------------------------------------*/
 757
 758 static void wait_skb_queue_empty(struct sk_buff_head *q)
 759 {
 760         unsigned long flags;
 761
 762         spin_lock_irqsave(&q->lock, flags);
 763         while (!skb_queue_empty(q)) {
 764                 spin_unlock_irqrestore(&q->lock, flags);
 765                 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 766                 set_current_state(TASK_UNINTERRUPTIBLE);
 767                 spin_lock_irqsave(&q->lock, flags);
 768         }
 769         spin_unlock_irqrestore(&q->lock, flags);
 770 }
 771
 772 // precondition: never called in_interrupt
 773 static void usbnet_terminate_urbs(struct usbnet *dev)
 774 {
 775         DECLARE_WAITQUEUE(wait, current);
 776         int temp;
 777
 778         /* ensure there are no more active urbs */
 779         add_wait_queue(&dev->wait, &wait);
 780         set_current_state(TASK_UNINTERRUPTIBLE);
 781         temp = unlink_urbs(dev, &dev->txq) +
 782                 unlink_urbs(dev, &dev->rxq);
 783
 784         /* maybe wait for deletions to finish. */
 785         wait_skb_queue_empty(&dev->rxq);
 786         wait_skb_queue_empty(&dev->txq);
 787         wait_skb_queue_empty(&dev->done);
 788         netif_dbg(dev, ifdown, dev->net,
 789                   "waited for %d urb completions\n", temp);
 790         set_current_state(TASK_RUNNING);
 791         remove_wait_queue(&dev->wait, &wait);
 792 }
 793
 794 int usbnet_stop (struct net_device *net)
 795 {
 796         struct usbnet           *dev = netdev_priv(net);
 797         struct driver_info      *info = dev->driver_info;
 798         int                     retval, pm, mpn;
 799
 800         clear_bit(EVENT_DEV_OPEN, &dev->flags);
 801         netif_stop_queue (net);
 802
 803         netif_info(dev, ifdown, dev->net,
 804                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 805                    net->stats.rx_packets, net->stats.tx_packets,
 806                    net->stats.rx_errors, net->stats.tx_errors);
 807
 808         /* to not race resume */
 809         pm = usb_autopm_get_interface(dev->intf);
 810         /* allow minidriver to stop correctly (wireless devices to turn off
 811          * radio etc) */
 812         if (info->stop) {
 813                 retval = info->stop(dev);
 814                 if (retval < 0)
 815                         netif_info(dev, ifdown, dev->net,
 816                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
 817                                    retval,
 818                                    dev->udev->bus->bus_name, dev->udev->devpath,
 819                                    info->description);
 820         }
 821
 822         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 823                 usbnet_terminate_urbs(dev);
 824
 825         usbnet_status_stop(dev);
 826
 827         usbnet_purge_paused_rxq(dev);
 828
 829         mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
 830
 831         /* deferred work (task, timer, softirq) must also stop.
 832          * can't flush_scheduled_work() until we drop rtnl (later),
 833          * else workers could deadlock; so make workers a NOP.
 834          */
 835         dev->flags = 0;
 836         del_timer_sync (&dev->delay);
 837         tasklet_kill (&dev->bh);
 838         if (!pm)
 839                 usb_autopm_put_interface(dev->intf);
 840
 841         if (info->manage_power && mpn)
 842                 info->manage_power(dev, 0);
 843         else
 844                 usb_autopm_put_interface(dev->intf);
 845
 846         return 0;
 847 }
 848 EXPORT_SYMBOL_GPL(usbnet_stop);
 849
 850 /*-------------------------------------------------------------------------*/
 851
 852 // posts reads, and enables write queuing
 853
 854 // precondition: never called in_interrupt
 855
 856 int usbnet_open (struct net_device *net)
 857 {
 858         struct usbnet           *dev = netdev_priv(net);
 859         int                     retval;
 860         struct driver_info      *info = dev->driver_info;
 861
 862         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 863                 netif_info(dev, ifup, dev->net,
 864                            "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 865                            retval,
 866                            dev->udev->bus->bus_name,
 867                            dev->udev->devpath,
 868                            info->description);
 869                 goto done_nopm;
 870         }
 871
 872         // put into "known safe" state
 873         if (info->reset && (retval = info->reset (dev)) < 0) {
 874                 netif_info(dev, ifup, dev->net,
 875                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 876                            retval,
 877                            dev->udev->bus->bus_name,
 878                            dev->udev->devpath,
 879                            info->description);
 880                 goto done;
 881         }
 882
 883         /* hard_mtu or rx_urb_size may change in reset() */
 884         usbnet_update_max_qlen(dev);
 885
 886         // insist peer be connected
 887         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 888                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 889                 goto done;
 890         }
 891
 892         /* start any status interrupt transfer */
 893         if (dev->interrupt) {
 894                 retval = usbnet_status_start(dev, GFP_KERNEL);
 895                 if (retval < 0) {
 896                         netif_err(dev, ifup, dev->net,
 897                                   "intr submit %d\n", retval);
 898                         goto done;
 899                 }
 900         }
 901
 902         set_bit(EVENT_DEV_OPEN, &dev->flags);
 903         netif_start_queue (net);
 904         netif_info(dev, ifup, dev->net,
 905                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 906                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 907                    dev->net->mtu,
 908                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 909                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 910                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 911                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 912                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 913                    "simple");
 914
 915         /* reset rx error state */
 916         dev->pkt_cnt = 0;
 917         dev->pkt_err = 0;
 918         clear_bit(EVENT_RX_KILL, &dev->flags);
 919
 920         // delay posting reads until we're fully open
 921         tasklet_schedule (&dev->bh);
 922         if (info->manage_power) {
 923                 retval = info->manage_power(dev, 1);
 924                 if (retval < 0) {
 925                         retval = 0;
 926                         set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
 927                 } else {
 928                         usb_autopm_put_interface(dev->intf);
 929                 }
 930         }
 931         return retval;
 932 done:
 933         usb_autopm_put_interface(dev->intf);
 934 done_nopm:
 935         return retval;
 936 }
 937 EXPORT_SYMBOL_GPL(usbnet_open);
 938
 939 /*-------------------------------------------------------------------------*/
 940
 941 /* ethtool methods; minidrivers may need to add some more, but
 942  * they'll probably want to use this base set.
 943  */
 944
 945 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 946 {
 947         struct usbnet *dev = netdev_priv(net);
 948
 949         if (!dev->mii.mdio_read)
 950                 return -EOPNOTSUPP;
 951
 952         return mii_ethtool_gset(&dev->mii, cmd);
 953 }
 954 EXPORT_SYMBOL_GPL(usbnet_get_settings);
 955
 956 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 957 {
 958         struct usbnet *dev = netdev_priv(net);
 959         int retval;
 960
 961         if (!dev->mii.mdio_write)
 962                 return -EOPNOTSUPP;
 963
 964         retval = mii_ethtool_sset(&dev->mii, cmd);
 965
 966         /* link speed/duplex might have changed */
 967         if (dev->driver_info->link_reset)
 968                 dev->driver_info->link_reset(dev);
 969
 970         /* hard_mtu or rx_urb_size may change in link_reset() */
 971         usbnet_update_max_qlen(dev);
 972
 973         return retval;
 974
 975 }
 976 EXPORT_SYMBOL_GPL(usbnet_set_settings);
 977
 978 u32 usbnet_get_link (struct net_device *net)
 979 {
 980         struct usbnet *dev = netdev_priv(net);
 981
 982         /* If a check_connect is defined, return its result */
 983         if (dev->driver_info->check_connect)
 984                 return dev->driver_info->check_connect (dev) == 0;
 985
 986         /* if the device has mii operations, use those */
 987         if (dev->mii.mdio_read)
 988                 return mii_link_ok(&dev->mii);
 989
 990         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 991         return ethtool_op_get_link(net);
 992 }
 993 EXPORT_SYMBOL_GPL(usbnet_get_link);
 994
 995 int usbnet_nway_reset(struct net_device *net)
 996 {
 997         struct usbnet *dev = netdev_priv(net);
 998
 999         if (!dev->mii.mdio_write)
1000                 return -EOPNOTSUPP;
1001
1002         return mii_nway_restart(&dev->mii);
1003 }
1004 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1005
1006 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1007 {
1008         struct usbnet *dev = netdev_priv(net);
1009
1010         strlcpy (info->driver, dev->driver_name, sizeof info->driver);
1011         strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
1012         strlcpy (info->fw_version, dev->driver_info->description,
1013                 sizeof info->fw_version);
1014         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1015 }
1016 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1017
1018 u32 usbnet_get_msglevel (struct net_device *net)
1019 {
1020         struct usbnet *dev = netdev_priv(net);
1021
1022         return dev->msg_enable;
1023 }
1024 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1025
1026 void usbnet_set_msglevel (struct net_device *net, u32 level)
1027 {
1028         struct usbnet *dev = netdev_priv(net);
1029
1030         dev->msg_enable = level;
1031 }
1032 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1033
1034 /* drivers may override default ethtool_ops in their bind() routine */
1035 static const struct ethtool_ops usbnet_ethtool_ops = {
1036         .get_settings           = usbnet_get_settings,
1037         .set_settings           = usbnet_set_settings,
1038         .get_link               = usbnet_get_link,
1039         .nway_reset             = usbnet_nway_reset,
1040         .get_drvinfo            = usbnet_get_drvinfo,
1041         .get_msglevel           = usbnet_get_msglevel,
1042         .set_msglevel           = usbnet_set_msglevel,
1043         .get_ts_info            = ethtool_op_get_ts_info,
1044 };
1045
1046 /*-------------------------------------------------------------------------*/
1047
1048 static void __handle_link_change(struct usbnet *dev)
1049 {
1050         if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1051                 return;
1052
1053         if (!netif_carrier_ok(dev->net)) {
1054                 /* kill URBs for reading packets to save bus bandwidth */
1055                 unlink_urbs(dev, &dev->rxq);
1056
1057                 /*
1058                  * tx_timeout will unlink URBs for sending packets and
1059                  * tx queue is stopped by netcore after link becomes off
1060                  */
1061         } else {
1062                 /* submitting URBs for reading packets */
1063                 tasklet_schedule(&dev->bh);
1064         }
1065
1066         /* hard_mtu or rx_urb_size may change during link change */
1067         usbnet_update_max_qlen(dev);
1068
1069         clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1070 }
1071
1072 static void usbnet_set_rx_mode(struct net_device *net)
1073 {
1074         struct usbnet           *dev = netdev_priv(net);
1075
1076         usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1077 }
1078
1079 static void __handle_set_rx_mode(struct usbnet *dev)
1080 {
1081         if (dev->driver_info->set_rx_mode)
1082                 (dev->driver_info->set_rx_mode)(dev);
1083
1084         clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1085 }
1086
1087 /* work that cannot be done in interrupt context uses keventd.
1088  *
1089  * NOTE:  with 2.5 we could do more of this using completion callbacks,
1090  * especially now that control transfers can be queued.
1091  */
1092 static void
1093 usbnet_deferred_kevent (struct work_struct *work)
1094 {
1095         struct usbnet           *dev =
1096                 container_of(work, struct usbnet, kevent);
1097         int                     status;
1098
1099         /* usb_clear_halt() needs a thread context */
1100         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1101                 unlink_urbs (dev, &dev->txq);
1102                 status = usb_autopm_get_interface(dev->intf);
1103                 if (status < 0)
1104                         goto fail_pipe;
1105                 status = usb_clear_halt (dev->udev, dev->out);
1106                 usb_autopm_put_interface(dev->intf);
1107                 if (status < 0 &&
1108                     status != -EPIPE &&
1109                     status != -ESHUTDOWN) {
1110                         if (netif_msg_tx_err (dev))
1111 fail_pipe:
1112                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1113                                            status);
1114                 } else {
1115                         clear_bit (EVENT_TX_HALT, &dev->flags);
1116                         if (status != -ESHUTDOWN)
1117                                 netif_wake_queue (dev->net);
1118                 }
1119         }
1120         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1121                 unlink_urbs (dev, &dev->rxq);
1122                 status = usb_autopm_get_interface(dev->intf);
1123                 if (status < 0)
1124                         goto fail_halt;
1125                 status = usb_clear_halt (dev->udev, dev->in);
1126                 usb_autopm_put_interface(dev->intf);
1127                 if (status < 0 &&
1128                     status != -EPIPE &&
1129                     status != -ESHUTDOWN) {
1130                         if (netif_msg_rx_err (dev))
1131 fail_halt:
1132                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1133                                            status);
1134                 } else {
1135                         clear_bit (EVENT_RX_HALT, &dev->flags);
1136                         tasklet_schedule (&dev->bh);
1137                 }
1138         }
1139
1140         /* tasklet could resubmit itself forever if memory is tight */
1141         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1142                 struct urb      *urb = NULL;
1143                 int resched = 1;
1144
1145                 if (netif_running (dev->net))
1146                         urb = usb_alloc_urb (0, GFP_KERNEL);
1147                 else
1148                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1149                 if (urb != NULL) {
1150                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1151                         status = usb_autopm_get_interface(dev->intf);
1152                         if (status < 0) {
1153                                 usb_free_urb(urb);
1154                                 goto fail_lowmem;
1155                         }
1156                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1157                                 resched = 0;
1158                         usb_autopm_put_interface(dev->intf);
1159 fail_lowmem:
1160                         if (resched)
1161                                 tasklet_schedule (&dev->bh);
1162                 }
1163         }
1164
1165         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1166                 struct driver_info      *info = dev->driver_info;
1167                 int                     retval = 0;
1168
1169                 clear_bit (EVENT_LINK_RESET, &dev->flags);
1170                 status = usb_autopm_get_interface(dev->intf);
1171                 if (status < 0)
1172                         goto skip_reset;
1173                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1174                         usb_autopm_put_interface(dev->intf);
1175 skip_reset:
1176                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1177                                     retval,
1178                                     dev->udev->bus->bus_name,
1179                                     dev->udev->devpath,
1180                                     info->description);
1181                 } else {
1182                         usb_autopm_put_interface(dev->intf);
1183                 }
1184
1185                 /* handle link change from link resetting */
1186                 __handle_link_change(dev);
1187         }
1188
1189         if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1190                 __handle_link_change(dev);
1191
1192         if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1193                 __handle_set_rx_mode(dev);
1194
1195
1196         if (dev->flags)
1197                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1198 }
1199
1200 /*-------------------------------------------------------------------------*/
1201
1202 static void tx_complete (struct urb *urb)
1203 {
1204         struct sk_buff          *skb = (struct sk_buff *) urb->context;
1205         struct skb_data         *entry = (struct skb_data *) skb->cb;
1206         struct usbnet           *dev = entry->dev;
1207
1208         if (urb->status == 0) {
1209                 dev->net->stats.tx_packets += entry->packets;
1210                 dev->net->stats.tx_bytes += entry->length;
1211         } else {
1212                 dev->net->stats.tx_errors++;
1213
1214                 switch (urb->status) {
1215                 case -EPIPE:
1216                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
1217                         break;
1218
1219                 /* software-driven interface shutdown */
1220                 case -ECONNRESET:               // async unlink
1221                 case -ESHUTDOWN:                // hardware gone
1222                         break;
1223
1224                 /* like rx, tx gets controller i/o faults during hub_wq
1225                  * delays and so it uses the same throttling mechanism.
1226                  */
1227                 case -EPROTO:
1228                 case -ETIME:
1229                 case -EILSEQ:
1230                         usb_mark_last_busy(dev->udev);
1231                         if (!timer_pending (&dev->delay)) {
1232                                 mod_timer (&dev->delay,
1233                                         jiffies + THROTTLE_JIFFIES);
1234                                 netif_dbg(dev, link, dev->net,
1235                                           "tx throttle %d\n", urb->status);
1236                         }
1237                         netif_stop_queue (dev->net);
1238                         break;
1239                 default:
1240                         netif_dbg(dev, tx_err, dev->net,
1241                                   "tx err %d\n", entry->urb->status);
1242                         break;
1243                 }
1244         }
1245
1246         usb_autopm_put_interface_async(dev->intf);
1247         (void) defer_bh(dev, skb, &dev->txq, tx_done);
1248 }
1249
1250 /*-------------------------------------------------------------------------*/
1251
1252 void usbnet_tx_timeout (struct net_device *net)
1253 {
1254         struct usbnet           *dev = netdev_priv(net);
1255
1256         unlink_urbs (dev, &dev->txq);
1257         tasklet_schedule (&dev->bh);
1258         /* this needs to be handled individually because the generic layer
1259          * doesn't know what is sufficient and could not restore private
1260          * information if a remedy of an unconditional reset were used.
1261          */
1262         if (dev->driver_info->recover)
1263                 (dev->driver_info->recover)(dev);
1264 }
1265 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1266
1267 /*-------------------------------------------------------------------------*/
1268
1269 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1270 {
1271         unsigned num_sgs, total_len = 0;
1272         int i, s = 0;
1273
1274         num_sgs = skb_shinfo(skb)->nr_frags + 1;
1275         if (num_sgs == 1)
1276                 return 0;
1277
1278         /* reserve one for zero packet */
1279         urb->sg = kmalloc((num_sgs + 1) * sizeof(struct scatterlist),
1280                           GFP_ATOMIC);
1281         if (!urb->sg)
1282                 return -ENOMEM;
1283
1284         urb->num_sgs = num_sgs;
1285         sg_init_table(urb->sg, urb->num_sgs + 1);
1286
1287         sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1288         total_len += skb_headlen(skb);
1289
1290         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1291                 struct skb_frag_struct *f = &skb_shinfo(skb)->frags[i];
1292
1293                 total_len += skb_frag_size(f);
1294                 sg_set_page(&urb->sg[i + s], f->page.p, f->size,
1295                                 f->page_offset);
1296         }
1297         urb->transfer_buffer_length = total_len;
1298
1299         return 1;
1300 }
1301
1302 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1303                                      struct net_device *net)
1304 {
1305         struct usbnet           *dev = netdev_priv(net);
1306         unsigned int                    length;
1307         struct urb              *urb = NULL;
1308         struct skb_data         *entry;
1309         struct driver_info      *info = dev->driver_info;
1310         unsigned long           flags;
1311         int retval;
1312
1313         if (skb)
1314                 skb_tx_timestamp(skb);
1315
1316         // some devices want funky USB-level framing, for
1317         // win32 driver (usually) and/or hardware quirks
1318         if (info->tx_fixup) {
1319                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1320                 if (!skb) {
1321                         /* packet collected; minidriver waiting for more */
1322                         if (info->flags & FLAG_MULTI_PACKET)
1323                                 goto not_drop;
1324                         netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1325                         goto drop;
1326                 }
1327         }
1328
1329         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1330                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1331                 goto drop;
1332         }
1333
1334         entry = (struct skb_data *) skb->cb;
1335         entry->urb = urb;
1336         entry->dev = dev;
1337
1338         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1339                         skb->data, skb->len, tx_complete, skb);
1340         if (dev->can_dma_sg) {
1341                 if (build_dma_sg(skb, urb) < 0)
1342                         goto drop;
1343         }
1344         length = urb->transfer_buffer_length;
1345
1346         /* don't assume the hardware handles USB_ZERO_PACKET
1347          * NOTE:  strictly conforming cdc-ether devices should expect
1348          * the ZLP here, but ignore the one-byte packet.
1349          * NOTE2: CDC NCM specification is different from CDC ECM when
1350          * handling ZLP/short packets, so cdc_ncm driver will make short
1351          * packet itself if needed.
1352          */
1353         if (length % dev->maxpacket == 0) {
1354                 if (!(info->flags & FLAG_SEND_ZLP)) {
1355                         if (!(info->flags & FLAG_MULTI_PACKET)) {
1356                                 length++;
1357                                 if (skb_tailroom(skb) && !urb->num_sgs) {
1358                                         skb->data[skb->len] = 0;
1359                                         __skb_put(skb, 1);
1360                                 } else if (urb->num_sgs)
1361                                         sg_set_buf(&urb->sg[urb->num_sgs++],
1362                                                         dev->padding_pkt, 1);
1363                         }
1364                 } else
1365                         urb->transfer_flags |= URB_ZERO_PACKET;
1366         }
1367         urb->transfer_buffer_length = length;
1368
1369         if (info->flags & FLAG_MULTI_PACKET) {
1370                 /* Driver has set number of packets and a length delta.
1371                  * Calculate the complete length and ensure that it's
1372                  * positive.
1373                  */
1374                 entry->length += length;
1375                 if (WARN_ON_ONCE(entry->length <= 0))
1376                         entry->length = length;
1377         } else {
1378                 usbnet_set_skb_tx_stats(skb, 1, length);
1379         }
1380
1381         spin_lock_irqsave(&dev->txq.lock, flags);
1382         retval = usb_autopm_get_interface_async(dev->intf);
1383         if (retval < 0) {
1384                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1385                 goto drop;
1386         }
1387
1388 #ifdef CONFIG_PM
1389         /* if this triggers the device is still a sleep */
1390         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1391                 /* transmission will be done in resume */
1392                 usb_anchor_urb(urb, &dev->deferred);
1393                 /* no use to process more packets */
1394                 netif_stop_queue(net);
1395                 usb_put_urb(urb);
1396                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1397                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1398                 goto deferred;
1399         }
1400 #endif
1401
1402         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1403         case -EPIPE:
1404                 netif_stop_queue (net);
1405                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1406                 usb_autopm_put_interface_async(dev->intf);
1407                 break;
1408         default:
1409                 usb_autopm_put_interface_async(dev->intf);
1410                 netif_dbg(dev, tx_err, dev->net,
1411                           "tx: submit urb err %d\n", retval);
1412                 break;
1413         case 0:
1414                 net->trans_start = jiffies;
1415                 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1416                 if (dev->txq.qlen >= TX_QLEN (dev))
1417                         netif_stop_queue (net);
1418         }
1419         spin_unlock_irqrestore (&dev->txq.lock, flags);
1420
1421         if (retval) {
1422                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1423 drop:
1424                 dev->net->stats.tx_dropped++;
1425 not_drop:
1426                 if (skb)
1427                         dev_kfree_skb_any (skb);
1428                 if (urb) {
1429                         kfree(urb->sg);
1430                         usb_free_urb(urb);
1431                 }
1432         } else
1433                 netif_dbg(dev, tx_queued, dev->net,
1434                           "> tx, len %u, type 0x%x\n", length, skb->protocol);
1435 #ifdef CONFIG_PM
1436 deferred:
1437 #endif
1438         return NETDEV_TX_OK;
1439 }
1440 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1441
1442 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1443 {
1444         struct urb      *urb;
1445         int             i;
1446         int             ret = 0;
1447
1448         /* don't refill the queue all at once */
1449         for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1450                 urb = usb_alloc_urb(0, flags);
1451                 if (urb != NULL) {
1452                         ret = rx_submit(dev, urb, flags);
1453                         if (ret)
1454                                 goto err;
1455                 } else {
1456                         ret = -ENOMEM;
1457                         goto err;
1458                 }
1459         }
1460 err:
1461         return ret;
1462 }
1463
1464 /*-------------------------------------------------------------------------*/
1465
1466 // tasklet (work deferred from completions, in_irq) or timer
1467
1468 static void usbnet_bh (unsigned long param)
1469 {
1470         struct usbnet           *dev = (struct usbnet *) param;
1471         struct sk_buff          *skb;
1472         struct skb_data         *entry;
1473
1474         while ((skb = skb_dequeue (&dev->done))) {
1475                 entry = (struct skb_data *) skb->cb;
1476                 switch (entry->state) {
1477                 case rx_done:
1478                         entry->state = rx_cleanup;
1479                         rx_process (dev, skb);
1480                         continue;
1481                 case tx_done:
1482                         kfree(entry->urb->sg);
1483                 case rx_cleanup:
1484                         usb_free_urb (entry->urb);
1485                         dev_kfree_skb (skb);
1486                         continue;
1487                 default:
1488                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1489                 }
1490         }
1491
1492         /* restart RX again after disabling due to high error rate */
1493         clear_bit(EVENT_RX_KILL, &dev->flags);
1494
1495         /* waiting for all pending urbs to complete?
1496          * only then can we forgo submitting anew
1497          */
1498         if (waitqueue_active(&dev->wait)) {
1499                 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1500                         wake_up_all(&dev->wait);
1501
1502         // or are we maybe short a few urbs?
1503         } else if (netif_running (dev->net) &&
1504                    netif_device_present (dev->net) &&
1505                    netif_carrier_ok(dev->net) &&
1506                    !timer_pending (&dev->delay) &&
1507                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1508                 int     temp = dev->rxq.qlen;
1509
1510                 if (temp < RX_QLEN(dev)) {
1511                         if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1512                                 return;
1513                         if (temp != dev->rxq.qlen)
1514                                 netif_dbg(dev, link, dev->net,
1515                                           "rxqlen %d --> %d\n",
1516                                           temp, dev->rxq.qlen);
1517                         if (dev->rxq.qlen < RX_QLEN(dev))
1518                                 tasklet_schedule (&dev->bh);
1519                 }
1520                 if (dev->txq.qlen < TX_QLEN (dev))
1521                         netif_wake_queue (dev->net);
1522         }
1523 }
1524
1525
1526 /*-------------------------------------------------------------------------
1527  *
1528  * USB Device Driver support
1529  *
1530  *-------------------------------------------------------------------------*/
1531
1532 // precondition: never called in_interrupt
1533
1534 void usbnet_disconnect (struct usb_interface *intf)
1535 {
1536         struct usbnet           *dev;
1537         struct usb_device       *xdev;
1538         struct net_device       *net;
1539
1540         dev = usb_get_intfdata(intf);
1541         usb_set_intfdata(intf, NULL);
1542         if (!dev)
1543                 return;
1544
1545         xdev = interface_to_usbdev (intf);
1546
1547         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1548                    intf->dev.driver->name,
1549                    xdev->bus->bus_name, xdev->devpath,
1550                    dev->driver_info->description);
1551
1552         net = dev->net;
1553         unregister_netdev (net);
1554
1555         cancel_work_sync(&dev->kevent);
1556
1557         usb_scuttle_anchored_urbs(&dev->deferred);
1558
1559         if (dev->driver_info->unbind)
1560                 dev->driver_info->unbind (dev, intf);
1561
1562         usb_kill_urb(dev->interrupt);
1563         usb_free_urb(dev->interrupt);
1564         kfree(dev->padding_pkt);
1565
1566         free_netdev(net);
1567 }
1568 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1569
1570 static const struct net_device_ops usbnet_netdev_ops = {
1571         .ndo_open               = usbnet_open,
1572         .ndo_stop               = usbnet_stop,
1573         .ndo_start_xmit         = usbnet_start_xmit,
1574         .ndo_tx_timeout         = usbnet_tx_timeout,
1575         .ndo_set_rx_mode        = usbnet_set_rx_mode,
1576         .ndo_change_mtu         = usbnet_change_mtu,
1577         .ndo_set_mac_address    = eth_mac_addr,
1578         .ndo_validate_addr      = eth_validate_addr,
1579 };
1580
1581 /*-------------------------------------------------------------------------*/
1582
1583 // precondition: never called in_interrupt
1584
1585 static struct device_type wlan_type = {
1586         .name   = "wlan",
1587 };
1588
1589 static struct device_type wwan_type = {
1590         .name   = "wwan",
1591 };
1592
1593 int
1594 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1595 {
1596         struct usbnet                   *dev;
1597         struct net_device               *net;
1598         struct usb_host_interface       *interface;
1599         struct driver_info              *info;
1600         struct usb_device               *xdev;
1601         int                             status;
1602         const char                      *name;
1603         struct usb_driver       *driver = to_usb_driver(udev->dev.driver);
1604
1605         /* usbnet already took usb runtime pm, so have to enable the feature
1606          * for usb interface, otherwise usb_autopm_get_interface may return
1607          * failure if RUNTIME_PM is enabled.
1608          */
1609         if (!driver->supports_autosuspend) {
1610                 driver->supports_autosuspend = 1;
1611                 pm_runtime_enable(&udev->dev);
1612         }
1613
1614         name = udev->dev.driver->name;
1615         info = (struct driver_info *) prod->driver_info;
1616         if (!info) {
1617                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1618                 return -ENODEV;
1619         }
1620         xdev = interface_to_usbdev (udev);
1621         interface = udev->cur_altsetting;
1622
1623         status = -ENOMEM;
1624
1625         // set up our own records
1626         net = alloc_etherdev(sizeof(*dev));
1627         if (!net)
1628                 goto out;
1629
1630         /* netdev_printk() needs this so do it as early as possible */
1631         SET_NETDEV_DEV(net, &udev->dev);
1632
1633         dev = netdev_priv(net);
1634         dev->udev = xdev;
1635         dev->intf = udev;
1636         dev->driver_info = info;
1637         dev->driver_name = name;
1638         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1639                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1640         init_waitqueue_head(&dev->wait);
1641         skb_queue_head_init (&dev->rxq);
1642         skb_queue_head_init (&dev->txq);
1643         skb_queue_head_init (&dev->done);
1644         skb_queue_head_init(&dev->rxq_pause);
1645         dev->bh.func = usbnet_bh;
1646         dev->bh.data = (unsigned long) dev;
1647         INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1648         init_usb_anchor(&dev->deferred);
1649         dev->delay.function = usbnet_bh;
1650         dev->delay.data = (unsigned long) dev;
1651         init_timer (&dev->delay);
1652         mutex_init (&dev->phy_mutex);
1653         mutex_init(&dev->interrupt_mutex);
1654         dev->interrupt_count = 0;
1655
1656         dev->net = net;
1657         strcpy (net->name, "usb%d");
1658         memcpy (net->dev_addr, node_id, sizeof node_id);
1659
1660         /* rx and tx sides can use different message sizes;
1661          * bind() should set rx_urb_size in that case.
1662          */
1663         dev->hard_mtu = net->mtu + net->hard_header_len;
1664 #if 0
1665 // dma_supported() is deeply broken on almost all architectures
1666         // possible with some EHCI controllers
1667         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1668                 net->features |= NETIF_F_HIGHDMA;
1669 #endif
1670
1671         net->netdev_ops = &usbnet_netdev_ops;
1672         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1673         net->ethtool_ops = &usbnet_ethtool_ops;
1674
1675         // allow device-specific bind/init procedures
1676         // NOTE net->name still not usable ...
1677         if (info->bind) {
1678                 status = info->bind (dev, udev);
1679                 if (status < 0)
1680                         goto out1;
1681
1682                 // heuristic:  "usb%d" for links we know are two-host,
1683                 // else "eth%d" when there's reasonable doubt.  userspace
1684                 // can rename the link if it knows better.
1685                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1686                     ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1687                      (net->dev_addr [0] & 0x02) == 0))
1688                         strcpy (net->name, "eth%d");
1689                 /* WLAN devices should always be named "wlan%d" */
1690                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1691                         strcpy(net->name, "wlan%d");
1692                 /* WWAN devices should always be named "wwan%d" */
1693                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1694                         strcpy(net->name, "wwan%d");
1695
1696                 /* devices that cannot do ARP */
1697                 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1698                         net->flags |= IFF_NOARP;
1699
1700                 /* maybe the remote can't receive an Ethernet MTU */
1701                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1702                         net->mtu = dev->hard_mtu - net->hard_header_len;
1703         } else if (!info->in || !info->out)
1704                 status = usbnet_get_endpoints (dev, udev);
1705         else {
1706                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1707                 dev->out = usb_sndbulkpipe (xdev, info->out);
1708                 if (!(info->flags & FLAG_NO_SETINT))
1709                         status = usb_set_interface (xdev,
1710                                 interface->desc.bInterfaceNumber,
1711                                 interface->desc.bAlternateSetting);
1712                 else
1713                         status = 0;
1714
1715         }
1716         if (status >= 0 && dev->status)
1717                 status = init_status (dev, udev);
1718         if (status < 0)
1719                 goto out3;
1720
1721         if (!dev->rx_urb_size)
1722                 dev->rx_urb_size = dev->hard_mtu;
1723         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1724
1725         /* let userspace know we have a random address */
1726         if (ether_addr_equal(net->dev_addr, node_id))
1727                 net->addr_assign_type = NET_ADDR_RANDOM;
1728
1729         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1730                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1731         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1732                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1733
1734         /* initialize max rx_qlen and tx_qlen */
1735         usbnet_update_max_qlen(dev);
1736
1737         if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1738                 !(info->flags & FLAG_MULTI_PACKET)) {
1739                 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1740                 if (!dev->padding_pkt) {
1741                         status = -ENOMEM;
1742                         goto out4;
1743                 }
1744         }
1745
1746         status = register_netdev (net);
1747         if (status)
1748                 goto out5;
1749         netif_info(dev, probe, dev->net,
1750                    "register '%s' at usb-%s-%s, %s, %pM\n",
1751                    udev->dev.driver->name,
1752                    xdev->bus->bus_name, xdev->devpath,
1753                    dev->driver_info->description,
1754                    net->dev_addr);
1755
1756         // ok, it's ready to go.
1757         usb_set_intfdata (udev, dev);
1758
1759         netif_device_attach (net);
1760
1761         if (dev->driver_info->flags & FLAG_LINK_INTR)
1762                 usbnet_link_change(dev, 0, 0);
1763
1764         return 0;
1765
1766 out5:
1767         kfree(dev->padding_pkt);
1768 out4:
1769         usb_free_urb(dev->interrupt);
1770 out3:
1771         if (info->unbind)
1772                 info->unbind (dev, udev);
1773 out1:
1774         free_netdev(net);
1775 out:
1776         return status;
1777 }
1778 EXPORT_SYMBOL_GPL(usbnet_probe);
1779
1780 /*-------------------------------------------------------------------------*/
1781
1782 /*
1783  * suspend the whole driver as soon as the first interface is suspended
1784  * resume only when the last interface is resumed
1785  */
1786
1787 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1788 {
1789         struct usbnet           *dev = usb_get_intfdata(intf);
1790
1791         if (!dev->suspend_count++) {
1792                 spin_lock_irq(&dev->txq.lock);
1793                 /* don't autosuspend while transmitting */
1794                 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1795                         dev->suspend_count--;
1796                         spin_unlock_irq(&dev->txq.lock);
1797                         return -EBUSY;
1798                 } else {
1799                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1800                         spin_unlock_irq(&dev->txq.lock);
1801                 }
1802                 /*
1803                  * accelerate emptying of the rx and queues, to avoid
1804                  * having everything error out.
1805                  */
1806                 netif_device_detach (dev->net);
1807                 usbnet_terminate_urbs(dev);
1808                 __usbnet_status_stop_force(dev);
1809
1810                 /*
1811                  * reattach so runtime management can use and
1812                  * wake the device
1813                  */
1814                 netif_device_attach (dev->net);
1815         }
1816         return 0;
1817 }
1818 EXPORT_SYMBOL_GPL(usbnet_suspend);
1819
1820 int usbnet_resume (struct usb_interface *intf)
1821 {
1822         struct usbnet           *dev = usb_get_intfdata(intf);
1823         struct sk_buff          *skb;
1824         struct urb              *res;
1825         int                     retval;
1826
1827         if (!--dev->suspend_count) {
1828                 /* resume interrupt URB if it was previously submitted */
1829                 __usbnet_status_start_force(dev, GFP_NOIO);
1830
1831                 spin_lock_irq(&dev->txq.lock);
1832                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1833
1834                         skb = (struct sk_buff *)res->context;
1835                         retval = usb_submit_urb(res, GFP_ATOMIC);
1836                         if (retval < 0) {
1837                                 dev_kfree_skb_any(skb);
1838                                 kfree(res->sg);
1839                                 usb_free_urb(res);
1840                                 usb_autopm_put_interface_async(dev->intf);
1841                         } else {
1842                                 dev->net->trans_start = jiffies;
1843                                 __skb_queue_tail(&dev->txq, skb);
1844                         }
1845                 }
1846
1847                 smp_mb();
1848                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1849                 spin_unlock_irq(&dev->txq.lock);
1850
1851                 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1852                         /* handle remote wakeup ASAP
1853                          * we cannot race against stop
1854                          */
1855                         if (netif_device_present(dev->net) &&
1856                                 !timer_pending(&dev->delay) &&
1857                                 !test_bit(EVENT_RX_HALT, &dev->flags))
1858                                         rx_alloc_submit(dev, GFP_NOIO);
1859
1860                         if (!(dev->txq.qlen >= TX_QLEN(dev)))
1861                                 netif_tx_wake_all_queues(dev->net);
1862                         tasklet_schedule (&dev->bh);
1863                 }
1864         }
1865
1866         if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1867                 usb_autopm_get_interface_no_resume(intf);
1868
1869         return 0;
1870 }
1871 EXPORT_SYMBOL_GPL(usbnet_resume);
1872
1873 /*
1874  * Either a subdriver implements manage_power, then it is assumed to always
1875  * be ready to be suspended or it reports the readiness to be suspended
1876  * explicitly
1877  */
1878 void usbnet_device_suggests_idle(struct usbnet *dev)
1879 {
1880         if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1881                 dev->intf->needs_remote_wakeup = 1;
1882                 usb_autopm_put_interface_async(dev->intf);
1883         }
1884 }
1885 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1886
1887 /*
1888  * For devices that can do without special commands
1889  */
1890 int usbnet_manage_power(struct usbnet *dev, int on)
1891 {
1892         dev->intf->needs_remote_wakeup = on;
1893         return 0;
1894 }
1895 EXPORT_SYMBOL(usbnet_manage_power);
1896
1897 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1898 {
1899         /* update link after link is reseted */
1900         if (link && !need_reset)
1901                 netif_carrier_on(dev->net);
1902         else
1903                 netif_carrier_off(dev->net);
1904
1905         if (need_reset && link)
1906                 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1907         else
1908                 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1909 }
1910 EXPORT_SYMBOL(usbnet_link_change);
1911
1912 /*-------------------------------------------------------------------------*/
1913 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1914                              u16 value, u16 index, void *data, u16 size)
1915 {
1916         void *buf = NULL;
1917         int err = -ENOMEM;
1918
1919         netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
1920                    " value=0x%04x index=0x%04x size=%d\n",
1921                    cmd, reqtype, value, index, size);
1922
1923         if (data) {
1924                 buf = kmalloc(size, GFP_KERNEL);
1925                 if (!buf)
1926                         goto out;
1927         }
1928
1929         err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
1930                               cmd, reqtype, value, index, buf, size,
1931                               USB_CTRL_GET_TIMEOUT);
1932         if (err > 0 && err <= size)
1933                 memcpy(data, buf, err);
1934         kfree(buf);
1935 out:
1936         return err;
1937 }
1938
1939 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1940                               u16 value, u16 index, const void *data,
1941                               u16 size)
1942 {
1943         void *buf = NULL;
1944         int err = -ENOMEM;
1945
1946         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
1947                    " value=0x%04x index=0x%04x size=%d\n",
1948                    cmd, reqtype, value, index, size);
1949
1950         if (data) {
1951                 buf = kmemdup(data, size, GFP_KERNEL);
1952                 if (!buf)
1953                         goto out;
1954         }
1955
1956         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
1957                               cmd, reqtype, value, index, buf, size,
1958                               USB_CTRL_SET_TIMEOUT);
1959         kfree(buf);
1960
1961 out:
1962         return err;
1963 }
1964
1965 /*
1966  * The function can't be called inside suspend/resume callback,
1967  * otherwise deadlock will be caused.
1968  */
1969 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1970                     u16 value, u16 index, void *data, u16 size)
1971 {
1972         int ret;
1973
1974         if (usb_autopm_get_interface(dev->intf) < 0)
1975                 return -ENODEV;
1976         ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
1977                                 data, size);
1978         usb_autopm_put_interface(dev->intf);
1979         return ret;
1980 }
1981 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
1982
1983 /*
1984  * The function can't be called inside suspend/resume callback,
1985  * otherwise deadlock will be caused.
1986  */
1987 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1988                      u16 value, u16 index, const void *data, u16 size)
1989 {
1990         int ret;
1991
1992         if (usb_autopm_get_interface(dev->intf) < 0)
1993                 return -ENODEV;
1994         ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
1995                                  data, size);
1996         usb_autopm_put_interface(dev->intf);
1997         return ret;
1998 }
1999 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2000
2001 /*
2002  * The function can be called inside suspend/resume callback safely
2003  * and should only be called by suspend/resume callback generally.
2004  */
2005 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2006                           u16 value, u16 index, void *data, u16 size)
2007 {
2008         return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2009                                  data, size);
2010 }
2011 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2012
2013 /*
2014  * The function can be called inside suspend/resume callback safely
2015  * and should only be called by suspend/resume callback generally.
2016  */
2017 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2018                           u16 value, u16 index, const void *data,
2019                           u16 size)
2020 {
2021         return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2022                                   data, size);
2023 }
2024 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2025
2026 static void usbnet_async_cmd_cb(struct urb *urb)
2027 {
2028         struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2029         int status = urb->status;
2030
2031         if (status < 0)
2032                 dev_dbg(&urb->dev->dev, "%s failed with %d",
2033                         __func__, status);
2034
2035         kfree(req);
2036         usb_free_urb(urb);
2037 }
2038
2039 /*
2040  * The caller must make sure that device can't be put into suspend
2041  * state until the control URB completes.
2042  */
2043 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2044                            u16 value, u16 index, const void *data, u16 size)
2045 {
2046         struct usb_ctrlrequest *req = NULL;
2047         struct urb *urb;
2048         int err = -ENOMEM;
2049         void *buf = NULL;
2050
2051         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2052                    " value=0x%04x index=0x%04x size=%d\n",
2053                    cmd, reqtype, value, index, size);
2054
2055         urb = usb_alloc_urb(0, GFP_ATOMIC);
2056         if (!urb) {
2057                 netdev_err(dev->net, "Error allocating URB in"
2058                            " %s!\n", __func__);
2059                 goto fail;
2060         }
2061
2062         if (data) {
2063                 buf = kmemdup(data, size, GFP_ATOMIC);
2064                 if (!buf) {
2065                         netdev_err(dev->net, "Error allocating buffer"
2066                                    " in %s!\n", __func__);
2067                         goto fail_free;
2068                 }
2069         }
2070
2071         req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2072         if (!req)
2073                 goto fail_free_buf;
2074
2075         req->bRequestType = reqtype;
2076         req->bRequest = cmd;
2077         req->wValue = cpu_to_le16(value);
2078         req->wIndex = cpu_to_le16(index);
2079         req->wLength = cpu_to_le16(size);
2080
2081         usb_fill_control_urb(urb, dev->udev,
2082                              usb_sndctrlpipe(dev->udev, 0),
2083                              (void *)req, buf, size,
2084                              usbnet_async_cmd_cb, req);
2085         urb->transfer_flags |= URB_FREE_BUFFER;
2086
2087         err = usb_submit_urb(urb, GFP_ATOMIC);
2088         if (err < 0) {
2089                 netdev_err(dev->net, "Error submitting the control"
2090                            " message: status=%d\n", err);
2091                 goto fail_free;
2092         }
2093         return 0;
2094
2095 fail_free_buf:
2096         kfree(buf);
2097 fail_free:
2098         kfree(req);
2099         usb_free_urb(urb);
2100 fail:
2101         return err;
2102
2103 }
2104 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2105 /*-------------------------------------------------------------------------*/
2106
2107 static int __init usbnet_init(void)
2108 {
2109         /* Compiler should optimize this out. */
2110         BUILD_BUG_ON(
2111                 FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
2112
2113         eth_random_addr(node_id);
2114         return 0;
2115 }
2116 module_init(usbnet_init);
2117
2118 static void __exit usbnet_exit(void)
2119 {
2120 }
2121 module_exit(usbnet_exit);
2122
2123 MODULE_AUTHOR("David Brownell");
2124 MODULE_DESCRIPTION("USB network driver framework");
2125 MODULE_LICENSE("GPL");