060918f49fea82779a37d326a4d1729189ddad28
[karo-tx-linux.git] / 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         skb->protocol = eth_type_trans (skb, dev->net);
328         dev->net->stats.rx_packets++;
329         dev->net->stats.rx_bytes += skb->len;
330
331         netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
332                   skb->len + sizeof (struct ethhdr), skb->protocol);
333         memset (skb->cb, 0, sizeof (struct skb_data));
334
335         if (skb_defer_rx_timestamp(skb))
336                 return;
337
338         status = netif_rx (skb);
339         if (status != NET_RX_SUCCESS)
340                 netif_dbg(dev, rx_err, dev->net,
341                           "netif_rx status %d\n", status);
342 }
343 EXPORT_SYMBOL_GPL(usbnet_skb_return);
344
345 /* must be called if hard_mtu or rx_urb_size changed */
346 void usbnet_update_max_qlen(struct usbnet *dev)
347 {
348         enum usb_device_speed speed = dev->udev->speed;
349
350         switch (speed) {
351         case USB_SPEED_HIGH:
352                 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
353                 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
354                 break;
355         case USB_SPEED_SUPER:
356                 /*
357                  * Not take default 5ms qlen for super speed HC to
358                  * save memory, and iperf tests show 2.5ms qlen can
359                  * work well
360                  */
361                 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
362                 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
363                 break;
364         default:
365                 dev->rx_qlen = dev->tx_qlen = 4;
366         }
367 }
368 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
369
370 \f
371 /*-------------------------------------------------------------------------
372  *
373  * Network Device Driver (peer link to "Host Device", from USB host)
374  *
375  *-------------------------------------------------------------------------*/
376
377 int usbnet_change_mtu (struct net_device *net, int new_mtu)
378 {
379         struct usbnet   *dev = netdev_priv(net);
380         int             ll_mtu = new_mtu + net->hard_header_len;
381         int             old_hard_mtu = dev->hard_mtu;
382         int             old_rx_urb_size = dev->rx_urb_size;
383
384         if (new_mtu <= 0)
385                 return -EINVAL;
386         // no second zero-length packet read wanted after mtu-sized packets
387         if ((ll_mtu % dev->maxpacket) == 0)
388                 return -EDOM;
389         net->mtu = new_mtu;
390
391         dev->hard_mtu = net->mtu + net->hard_header_len;
392         if (dev->rx_urb_size == old_hard_mtu) {
393                 dev->rx_urb_size = dev->hard_mtu;
394                 if (dev->rx_urb_size > old_rx_urb_size)
395                         usbnet_unlink_rx_urbs(dev);
396         }
397
398         /* max qlen depend on hard_mtu and rx_urb_size */
399         usbnet_update_max_qlen(dev);
400
401         return 0;
402 }
403 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
404
405 /* The caller must hold list->lock */
406 static void __usbnet_queue_skb(struct sk_buff_head *list,
407                         struct sk_buff *newsk, enum skb_state state)
408 {
409         struct skb_data *entry = (struct skb_data *) newsk->cb;
410
411         __skb_queue_tail(list, newsk);
412         entry->state = state;
413 }
414
415 /*-------------------------------------------------------------------------*/
416
417 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
418  * completion callbacks.  2.5 should have fixed those bugs...
419  */
420
421 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
422                 struct sk_buff_head *list, enum skb_state state)
423 {
424         unsigned long           flags;
425         enum skb_state          old_state;
426         struct skb_data *entry = (struct skb_data *) skb->cb;
427
428         spin_lock_irqsave(&list->lock, flags);
429         old_state = entry->state;
430         entry->state = state;
431         __skb_unlink(skb, list);
432
433         /* defer_bh() is never called with list == &dev->done.
434          * spin_lock_nested() tells lockdep that it is OK to take
435          * dev->done.lock here with list->lock held.
436          */
437         spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
438
439         __skb_queue_tail(&dev->done, skb);
440         if (dev->done.qlen == 1)
441                 tasklet_schedule(&dev->bh);
442         spin_unlock(&dev->done.lock);
443         spin_unlock_irqrestore(&list->lock, flags);
444         return old_state;
445 }
446
447 /* some work can't be done in tasklets, so we use keventd
448  *
449  * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
450  * but tasklet_schedule() doesn't.  hope the failure is rare.
451  */
452 void usbnet_defer_kevent (struct usbnet *dev, int work)
453 {
454         set_bit (work, &dev->flags);
455         if (!schedule_work (&dev->kevent)) {
456                 if (net_ratelimit())
457                         netdev_err(dev->net, "kevent %d may have been dropped\n", work);
458         } else {
459                 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
460         }
461 }
462 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
463
464 /*-------------------------------------------------------------------------*/
465
466 static void rx_complete (struct urb *urb);
467
468 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
469 {
470         struct sk_buff          *skb;
471         struct skb_data         *entry;
472         int                     retval = 0;
473         unsigned long           lockflags;
474         size_t                  size = dev->rx_urb_size;
475
476         /* prevent rx skb allocation when error ratio is high */
477         if (test_bit(EVENT_RX_KILL, &dev->flags)) {
478                 usb_free_urb(urb);
479                 return -ENOLINK;
480         }
481
482         skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
483         if (!skb) {
484                 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
485                 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
486                 usb_free_urb (urb);
487                 return -ENOMEM;
488         }
489
490         entry = (struct skb_data *) skb->cb;
491         entry->urb = urb;
492         entry->dev = dev;
493         entry->length = 0;
494
495         usb_fill_bulk_urb (urb, dev->udev, dev->in,
496                 skb->data, size, rx_complete, skb);
497
498         spin_lock_irqsave (&dev->rxq.lock, lockflags);
499
500         if (netif_running (dev->net) &&
501             netif_device_present (dev->net) &&
502             !test_bit (EVENT_RX_HALT, &dev->flags) &&
503             !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
504                 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
505                 case -EPIPE:
506                         usbnet_defer_kevent (dev, EVENT_RX_HALT);
507                         break;
508                 case -ENOMEM:
509                         usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
510                         break;
511                 case -ENODEV:
512                         netif_dbg(dev, ifdown, dev->net, "device gone\n");
513                         netif_device_detach (dev->net);
514                         break;
515                 case -EHOSTUNREACH:
516                         retval = -ENOLINK;
517                         break;
518                 default:
519                         netif_dbg(dev, rx_err, dev->net,
520                                   "rx submit, %d\n", retval);
521                         tasklet_schedule (&dev->bh);
522                         break;
523                 case 0:
524                         __usbnet_queue_skb(&dev->rxq, skb, rx_start);
525                 }
526         } else {
527                 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
528                 retval = -ENOLINK;
529         }
530         spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
531         if (retval) {
532                 dev_kfree_skb_any (skb);
533                 usb_free_urb (urb);
534         }
535         return retval;
536 }
537
538
539 /*-------------------------------------------------------------------------*/
540
541 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
542 {
543         if (dev->driver_info->rx_fixup &&
544             !dev->driver_info->rx_fixup (dev, skb)) {
545                 /* With RX_ASSEMBLE, rx_fixup() must update counters */
546                 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
547                         dev->net->stats.rx_errors++;
548                 goto done;
549         }
550         // else network stack removes extra byte if we forced a short packet
551
552         /* all data was already cloned from skb inside the driver */
553         if (dev->driver_info->flags & FLAG_MULTI_PACKET)
554                 goto done;
555
556         if (skb->len < ETH_HLEN) {
557                 dev->net->stats.rx_errors++;
558                 dev->net->stats.rx_length_errors++;
559                 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
560         } else {
561                 usbnet_skb_return(dev, skb);
562                 return;
563         }
564
565 done:
566         skb_queue_tail(&dev->done, skb);
567 }
568
569 /*-------------------------------------------------------------------------*/
570
571 static void rx_complete (struct urb *urb)
572 {
573         struct sk_buff          *skb = (struct sk_buff *) urb->context;
574         struct skb_data         *entry = (struct skb_data *) skb->cb;
575         struct usbnet           *dev = entry->dev;
576         int                     urb_status = urb->status;
577         enum skb_state          state;
578
579         skb_put (skb, urb->actual_length);
580         state = rx_done;
581         entry->urb = NULL;
582
583         switch (urb_status) {
584         /* success */
585         case 0:
586                 break;
587
588         /* stalls need manual reset. this is rare ... except that
589          * when going through USB 2.0 TTs, unplug appears this way.
590          * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
591          * storm, recovering as needed.
592          */
593         case -EPIPE:
594                 dev->net->stats.rx_errors++;
595                 usbnet_defer_kevent (dev, EVENT_RX_HALT);
596                 // FALLTHROUGH
597
598         /* software-driven interface shutdown */
599         case -ECONNRESET:               /* async unlink */
600         case -ESHUTDOWN:                /* hardware gone */
601                 netif_dbg(dev, ifdown, dev->net,
602                           "rx shutdown, code %d\n", urb_status);
603                 goto block;
604
605         /* we get controller i/o faults during hub_wq disconnect() delays.
606          * throttle down resubmits, to avoid log floods; just temporarily,
607          * so we still recover when the fault isn't a hub_wq delay.
608          */
609         case -EPROTO:
610         case -ETIME:
611         case -EILSEQ:
612                 dev->net->stats.rx_errors++;
613                 if (!timer_pending (&dev->delay)) {
614                         mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
615                         netif_dbg(dev, link, dev->net,
616                                   "rx throttle %d\n", urb_status);
617                 }
618 block:
619                 state = rx_cleanup;
620                 entry->urb = urb;
621                 urb = NULL;
622                 break;
623
624         /* data overrun ... flush fifo? */
625         case -EOVERFLOW:
626                 dev->net->stats.rx_over_errors++;
627                 // FALLTHROUGH
628
629         default:
630                 state = rx_cleanup;
631                 dev->net->stats.rx_errors++;
632                 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
633                 break;
634         }
635
636         /* stop rx if packet error rate is high */
637         if (++dev->pkt_cnt > 30) {
638                 dev->pkt_cnt = 0;
639                 dev->pkt_err = 0;
640         } else {
641                 if (state == rx_cleanup)
642                         dev->pkt_err++;
643                 if (dev->pkt_err > 20)
644                         set_bit(EVENT_RX_KILL, &dev->flags);
645         }
646
647         state = defer_bh(dev, skb, &dev->rxq, state);
648
649         if (urb) {
650                 if (netif_running (dev->net) &&
651                     !test_bit (EVENT_RX_HALT, &dev->flags) &&
652                     state != unlink_start) {
653                         rx_submit (dev, urb, GFP_ATOMIC);
654                         usb_mark_last_busy(dev->udev);
655                         return;
656                 }
657                 usb_free_urb (urb);
658         }
659         netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
660 }
661
662 /*-------------------------------------------------------------------------*/
663 void usbnet_pause_rx(struct usbnet *dev)
664 {
665         set_bit(EVENT_RX_PAUSED, &dev->flags);
666
667         netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
668 }
669 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
670
671 void usbnet_resume_rx(struct usbnet *dev)
672 {
673         struct sk_buff *skb;
674         int num = 0;
675
676         clear_bit(EVENT_RX_PAUSED, &dev->flags);
677
678         while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
679                 usbnet_skb_return(dev, skb);
680                 num++;
681         }
682
683         tasklet_schedule(&dev->bh);
684
685         netif_dbg(dev, rx_status, dev->net,
686                   "paused rx queue disabled, %d skbs requeued\n", num);
687 }
688 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
689
690 void usbnet_purge_paused_rxq(struct usbnet *dev)
691 {
692         skb_queue_purge(&dev->rxq_pause);
693 }
694 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
695
696 /*-------------------------------------------------------------------------*/
697
698 // unlink pending rx/tx; completion handlers do all other cleanup
699
700 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
701 {
702         unsigned long           flags;
703         struct sk_buff          *skb;
704         int                     count = 0;
705
706         spin_lock_irqsave (&q->lock, flags);
707         while (!skb_queue_empty(q)) {
708                 struct skb_data         *entry;
709                 struct urb              *urb;
710                 int                     retval;
711
712                 skb_queue_walk(q, skb) {
713                         entry = (struct skb_data *) skb->cb;
714                         if (entry->state != unlink_start)
715                                 goto found;
716                 }
717                 break;
718 found:
719                 entry->state = unlink_start;
720                 urb = entry->urb;
721
722                 /*
723                  * Get reference count of the URB to avoid it to be
724                  * freed during usb_unlink_urb, which may trigger
725                  * use-after-free problem inside usb_unlink_urb since
726                  * usb_unlink_urb is always racing with .complete
727                  * handler(include defer_bh).
728                  */
729                 usb_get_urb(urb);
730                 spin_unlock_irqrestore(&q->lock, flags);
731                 // during some PM-driven resume scenarios,
732                 // these (async) unlinks complete immediately
733                 retval = usb_unlink_urb (urb);
734                 if (retval != -EINPROGRESS && retval != 0)
735                         netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
736                 else
737                         count++;
738                 usb_put_urb(urb);
739                 spin_lock_irqsave(&q->lock, flags);
740         }
741         spin_unlock_irqrestore (&q->lock, flags);
742         return count;
743 }
744
745 // Flush all pending rx urbs
746 // minidrivers may need to do this when the MTU changes
747
748 void usbnet_unlink_rx_urbs(struct usbnet *dev)
749 {
750         if (netif_running(dev->net)) {
751                 (void) unlink_urbs (dev, &dev->rxq);
752                 tasklet_schedule(&dev->bh);
753         }
754 }
755 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
756
757 /*-------------------------------------------------------------------------*/
758
759 static void wait_skb_queue_empty(struct sk_buff_head *q)
760 {
761         unsigned long flags;
762
763         spin_lock_irqsave(&q->lock, flags);
764         while (!skb_queue_empty(q)) {
765                 spin_unlock_irqrestore(&q->lock, flags);
766                 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
767                 set_current_state(TASK_UNINTERRUPTIBLE);
768                 spin_lock_irqsave(&q->lock, flags);
769         }
770         spin_unlock_irqrestore(&q->lock, flags);
771 }
772
773 // precondition: never called in_interrupt
774 static void usbnet_terminate_urbs(struct usbnet *dev)
775 {
776         DECLARE_WAITQUEUE(wait, current);
777         int temp;
778
779         /* ensure there are no more active urbs */
780         add_wait_queue(&dev->wait, &wait);
781         set_current_state(TASK_UNINTERRUPTIBLE);
782         temp = unlink_urbs(dev, &dev->txq) +
783                 unlink_urbs(dev, &dev->rxq);
784
785         /* maybe wait for deletions to finish. */
786         wait_skb_queue_empty(&dev->rxq);
787         wait_skb_queue_empty(&dev->txq);
788         wait_skb_queue_empty(&dev->done);
789         netif_dbg(dev, ifdown, dev->net,
790                   "waited for %d urb completions\n", temp);
791         set_current_state(TASK_RUNNING);
792         remove_wait_queue(&dev->wait, &wait);
793 }
794
795 int usbnet_stop (struct net_device *net)
796 {
797         struct usbnet           *dev = netdev_priv(net);
798         struct driver_info      *info = dev->driver_info;
799         int                     retval, pm, mpn;
800
801         clear_bit(EVENT_DEV_OPEN, &dev->flags);
802         netif_stop_queue (net);
803
804         netif_info(dev, ifdown, dev->net,
805                    "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
806                    net->stats.rx_packets, net->stats.tx_packets,
807                    net->stats.rx_errors, net->stats.tx_errors);
808
809         /* to not race resume */
810         pm = usb_autopm_get_interface(dev->intf);
811         /* allow minidriver to stop correctly (wireless devices to turn off
812          * radio etc) */
813         if (info->stop) {
814                 retval = info->stop(dev);
815                 if (retval < 0)
816                         netif_info(dev, ifdown, dev->net,
817                                    "stop fail (%d) usbnet usb-%s-%s, %s\n",
818                                    retval,
819                                    dev->udev->bus->bus_name, dev->udev->devpath,
820                                    info->description);
821         }
822
823         if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
824                 usbnet_terminate_urbs(dev);
825
826         usbnet_status_stop(dev);
827
828         usbnet_purge_paused_rxq(dev);
829
830         mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
831
832         /* deferred work (task, timer, softirq) must also stop.
833          * can't flush_scheduled_work() until we drop rtnl (later),
834          * else workers could deadlock; so make workers a NOP.
835          */
836         dev->flags = 0;
837         del_timer_sync (&dev->delay);
838         tasklet_kill (&dev->bh);
839         if (!pm)
840                 usb_autopm_put_interface(dev->intf);
841
842         if (info->manage_power && mpn)
843                 info->manage_power(dev, 0);
844         else
845                 usb_autopm_put_interface(dev->intf);
846
847         return 0;
848 }
849 EXPORT_SYMBOL_GPL(usbnet_stop);
850
851 /*-------------------------------------------------------------------------*/
852
853 // posts reads, and enables write queuing
854
855 // precondition: never called in_interrupt
856
857 int usbnet_open (struct net_device *net)
858 {
859         struct usbnet           *dev = netdev_priv(net);
860         int                     retval;
861         struct driver_info      *info = dev->driver_info;
862
863         if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
864                 netif_info(dev, ifup, dev->net,
865                            "resumption fail (%d) usbnet usb-%s-%s, %s\n",
866                            retval,
867                            dev->udev->bus->bus_name,
868                            dev->udev->devpath,
869                            info->description);
870                 goto done_nopm;
871         }
872
873         // put into "known safe" state
874         if (info->reset && (retval = info->reset (dev)) < 0) {
875                 netif_info(dev, ifup, dev->net,
876                            "open reset fail (%d) usbnet usb-%s-%s, %s\n",
877                            retval,
878                            dev->udev->bus->bus_name,
879                            dev->udev->devpath,
880                            info->description);
881                 goto done;
882         }
883
884         /* hard_mtu or rx_urb_size may change in reset() */
885         usbnet_update_max_qlen(dev);
886
887         // insist peer be connected
888         if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
889                 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
890                 goto done;
891         }
892
893         /* start any status interrupt transfer */
894         if (dev->interrupt) {
895                 retval = usbnet_status_start(dev, GFP_KERNEL);
896                 if (retval < 0) {
897                         netif_err(dev, ifup, dev->net,
898                                   "intr submit %d\n", retval);
899                         goto done;
900                 }
901         }
902
903         set_bit(EVENT_DEV_OPEN, &dev->flags);
904         netif_start_queue (net);
905         netif_info(dev, ifup, dev->net,
906                    "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
907                    (int)RX_QLEN(dev), (int)TX_QLEN(dev),
908                    dev->net->mtu,
909                    (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
910                    (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
911                    (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
912                    (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
913                    (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
914                    "simple");
915
916         /* reset rx error state */
917         dev->pkt_cnt = 0;
918         dev->pkt_err = 0;
919         clear_bit(EVENT_RX_KILL, &dev->flags);
920
921         // delay posting reads until we're fully open
922         tasklet_schedule (&dev->bh);
923         if (info->manage_power) {
924                 retval = info->manage_power(dev, 1);
925                 if (retval < 0) {
926                         retval = 0;
927                         set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
928                 } else {
929                         usb_autopm_put_interface(dev->intf);
930                 }
931         }
932         return retval;
933 done:
934         usb_autopm_put_interface(dev->intf);
935 done_nopm:
936         return retval;
937 }
938 EXPORT_SYMBOL_GPL(usbnet_open);
939
940 /*-------------------------------------------------------------------------*/
941
942 /* ethtool methods; minidrivers may need to add some more, but
943  * they'll probably want to use this base set.
944  */
945
946 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
947 {
948         struct usbnet *dev = netdev_priv(net);
949
950         if (!dev->mii.mdio_read)
951                 return -EOPNOTSUPP;
952
953         return mii_ethtool_gset(&dev->mii, cmd);
954 }
955 EXPORT_SYMBOL_GPL(usbnet_get_settings);
956
957 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
958 {
959         struct usbnet *dev = netdev_priv(net);
960         int retval;
961
962         if (!dev->mii.mdio_write)
963                 return -EOPNOTSUPP;
964
965         retval = mii_ethtool_sset(&dev->mii, cmd);
966
967         /* link speed/duplex might have changed */
968         if (dev->driver_info->link_reset)
969                 dev->driver_info->link_reset(dev);
970
971         /* hard_mtu or rx_urb_size may change in link_reset() */
972         usbnet_update_max_qlen(dev);
973
974         return retval;
975
976 }
977 EXPORT_SYMBOL_GPL(usbnet_set_settings);
978
979 u32 usbnet_get_link (struct net_device *net)
980 {
981         struct usbnet *dev = netdev_priv(net);
982
983         /* If a check_connect is defined, return its result */
984         if (dev->driver_info->check_connect)
985                 return dev->driver_info->check_connect (dev) == 0;
986
987         /* if the device has mii operations, use those */
988         if (dev->mii.mdio_read)
989                 return mii_link_ok(&dev->mii);
990
991         /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
992         return ethtool_op_get_link(net);
993 }
994 EXPORT_SYMBOL_GPL(usbnet_get_link);
995
996 int usbnet_nway_reset(struct net_device *net)
997 {
998         struct usbnet *dev = netdev_priv(net);
999
1000         if (!dev->mii.mdio_write)
1001                 return -EOPNOTSUPP;
1002
1003         return mii_nway_restart(&dev->mii);
1004 }
1005 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1006
1007 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1008 {
1009         struct usbnet *dev = netdev_priv(net);
1010
1011         strlcpy (info->driver, dev->driver_name, sizeof info->driver);
1012         strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
1013         strlcpy (info->fw_version, dev->driver_info->description,
1014                 sizeof info->fw_version);
1015         usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1016 }
1017 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1018
1019 u32 usbnet_get_msglevel (struct net_device *net)
1020 {
1021         struct usbnet *dev = netdev_priv(net);
1022
1023         return dev->msg_enable;
1024 }
1025 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1026
1027 void usbnet_set_msglevel (struct net_device *net, u32 level)
1028 {
1029         struct usbnet *dev = netdev_priv(net);
1030
1031         dev->msg_enable = level;
1032 }
1033 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1034
1035 /* drivers may override default ethtool_ops in their bind() routine */
1036 static const struct ethtool_ops usbnet_ethtool_ops = {
1037         .get_settings           = usbnet_get_settings,
1038         .set_settings           = usbnet_set_settings,
1039         .get_link               = usbnet_get_link,
1040         .nway_reset             = usbnet_nway_reset,
1041         .get_drvinfo            = usbnet_get_drvinfo,
1042         .get_msglevel           = usbnet_get_msglevel,
1043         .set_msglevel           = usbnet_set_msglevel,
1044         .get_ts_info            = ethtool_op_get_ts_info,
1045 };
1046
1047 /*-------------------------------------------------------------------------*/
1048
1049 static void __handle_link_change(struct usbnet *dev)
1050 {
1051         if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1052                 return;
1053
1054         if (!netif_carrier_ok(dev->net)) {
1055                 /* kill URBs for reading packets to save bus bandwidth */
1056                 unlink_urbs(dev, &dev->rxq);
1057
1058                 /*
1059                  * tx_timeout will unlink URBs for sending packets and
1060                  * tx queue is stopped by netcore after link becomes off
1061                  */
1062         } else {
1063                 /* submitting URBs for reading packets */
1064                 tasklet_schedule(&dev->bh);
1065         }
1066
1067         /* hard_mtu or rx_urb_size may change during link change */
1068         usbnet_update_max_qlen(dev);
1069
1070         clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1071 }
1072
1073 static void usbnet_set_rx_mode(struct net_device *net)
1074 {
1075         struct usbnet           *dev = netdev_priv(net);
1076
1077         usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1078 }
1079
1080 static void __handle_set_rx_mode(struct usbnet *dev)
1081 {
1082         if (dev->driver_info->set_rx_mode)
1083                 (dev->driver_info->set_rx_mode)(dev);
1084
1085         clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1086 }
1087
1088 /* work that cannot be done in interrupt context uses keventd.
1089  *
1090  * NOTE:  with 2.5 we could do more of this using completion callbacks,
1091  * especially now that control transfers can be queued.
1092  */
1093 static void
1094 usbnet_deferred_kevent (struct work_struct *work)
1095 {
1096         struct usbnet           *dev =
1097                 container_of(work, struct usbnet, kevent);
1098         int                     status;
1099
1100         /* usb_clear_halt() needs a thread context */
1101         if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1102                 unlink_urbs (dev, &dev->txq);
1103                 status = usb_autopm_get_interface(dev->intf);
1104                 if (status < 0)
1105                         goto fail_pipe;
1106                 status = usb_clear_halt (dev->udev, dev->out);
1107                 usb_autopm_put_interface(dev->intf);
1108                 if (status < 0 &&
1109                     status != -EPIPE &&
1110                     status != -ESHUTDOWN) {
1111                         if (netif_msg_tx_err (dev))
1112 fail_pipe:
1113                                 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1114                                            status);
1115                 } else {
1116                         clear_bit (EVENT_TX_HALT, &dev->flags);
1117                         if (status != -ESHUTDOWN)
1118                                 netif_wake_queue (dev->net);
1119                 }
1120         }
1121         if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1122                 unlink_urbs (dev, &dev->rxq);
1123                 status = usb_autopm_get_interface(dev->intf);
1124                 if (status < 0)
1125                         goto fail_halt;
1126                 status = usb_clear_halt (dev->udev, dev->in);
1127                 usb_autopm_put_interface(dev->intf);
1128                 if (status < 0 &&
1129                     status != -EPIPE &&
1130                     status != -ESHUTDOWN) {
1131                         if (netif_msg_rx_err (dev))
1132 fail_halt:
1133                                 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1134                                            status);
1135                 } else {
1136                         clear_bit (EVENT_RX_HALT, &dev->flags);
1137                         tasklet_schedule (&dev->bh);
1138                 }
1139         }
1140
1141         /* tasklet could resubmit itself forever if memory is tight */
1142         if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1143                 struct urb      *urb = NULL;
1144                 int resched = 1;
1145
1146                 if (netif_running (dev->net))
1147                         urb = usb_alloc_urb (0, GFP_KERNEL);
1148                 else
1149                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1150                 if (urb != NULL) {
1151                         clear_bit (EVENT_RX_MEMORY, &dev->flags);
1152                         status = usb_autopm_get_interface(dev->intf);
1153                         if (status < 0) {
1154                                 usb_free_urb(urb);
1155                                 goto fail_lowmem;
1156                         }
1157                         if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1158                                 resched = 0;
1159                         usb_autopm_put_interface(dev->intf);
1160 fail_lowmem:
1161                         if (resched)
1162                                 tasklet_schedule (&dev->bh);
1163                 }
1164         }
1165
1166         if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1167                 struct driver_info      *info = dev->driver_info;
1168                 int                     retval = 0;
1169
1170                 clear_bit (EVENT_LINK_RESET, &dev->flags);
1171                 status = usb_autopm_get_interface(dev->intf);
1172                 if (status < 0)
1173                         goto skip_reset;
1174                 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1175                         usb_autopm_put_interface(dev->intf);
1176 skip_reset:
1177                         netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1178                                     retval,
1179                                     dev->udev->bus->bus_name,
1180                                     dev->udev->devpath,
1181                                     info->description);
1182                 } else {
1183                         usb_autopm_put_interface(dev->intf);
1184                 }
1185
1186                 /* handle link change from link resetting */
1187                 __handle_link_change(dev);
1188         }
1189
1190         if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1191                 __handle_link_change(dev);
1192
1193         if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1194                 __handle_set_rx_mode(dev);
1195
1196
1197         if (dev->flags)
1198                 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1199 }
1200
1201 /*-------------------------------------------------------------------------*/
1202
1203 static void tx_complete (struct urb *urb)
1204 {
1205         struct sk_buff          *skb = (struct sk_buff *) urb->context;
1206         struct skb_data         *entry = (struct skb_data *) skb->cb;
1207         struct usbnet           *dev = entry->dev;
1208
1209         if (urb->status == 0) {
1210                 dev->net->stats.tx_packets += entry->packets;
1211                 dev->net->stats.tx_bytes += entry->length;
1212         } else {
1213                 dev->net->stats.tx_errors++;
1214
1215                 switch (urb->status) {
1216                 case -EPIPE:
1217                         usbnet_defer_kevent (dev, EVENT_TX_HALT);
1218                         break;
1219
1220                 /* software-driven interface shutdown */
1221                 case -ECONNRESET:               // async unlink
1222                 case -ESHUTDOWN:                // hardware gone
1223                         break;
1224
1225                 /* like rx, tx gets controller i/o faults during hub_wq
1226                  * delays and so it uses the same throttling mechanism.
1227                  */
1228                 case -EPROTO:
1229                 case -ETIME:
1230                 case -EILSEQ:
1231                         usb_mark_last_busy(dev->udev);
1232                         if (!timer_pending (&dev->delay)) {
1233                                 mod_timer (&dev->delay,
1234                                         jiffies + THROTTLE_JIFFIES);
1235                                 netif_dbg(dev, link, dev->net,
1236                                           "tx throttle %d\n", urb->status);
1237                         }
1238                         netif_stop_queue (dev->net);
1239                         break;
1240                 default:
1241                         netif_dbg(dev, tx_err, dev->net,
1242                                   "tx err %d\n", entry->urb->status);
1243                         break;
1244                 }
1245         }
1246
1247         usb_autopm_put_interface_async(dev->intf);
1248         (void) defer_bh(dev, skb, &dev->txq, tx_done);
1249 }
1250
1251 /*-------------------------------------------------------------------------*/
1252
1253 void usbnet_tx_timeout (struct net_device *net)
1254 {
1255         struct usbnet           *dev = netdev_priv(net);
1256
1257         unlink_urbs (dev, &dev->txq);
1258         tasklet_schedule (&dev->bh);
1259         /* this needs to be handled individually because the generic layer
1260          * doesn't know what is sufficient and could not restore private
1261          * information if a remedy of an unconditional reset were used.
1262          */
1263         if (dev->driver_info->recover)
1264                 (dev->driver_info->recover)(dev);
1265 }
1266 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1267
1268 /*-------------------------------------------------------------------------*/
1269
1270 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1271 {
1272         unsigned num_sgs, total_len = 0;
1273         int i, s = 0;
1274
1275         num_sgs = skb_shinfo(skb)->nr_frags + 1;
1276         if (num_sgs == 1)
1277                 return 0;
1278
1279         /* reserve one for zero packet */
1280         urb->sg = kmalloc((num_sgs + 1) * sizeof(struct scatterlist),
1281                           GFP_ATOMIC);
1282         if (!urb->sg)
1283                 return -ENOMEM;
1284
1285         urb->num_sgs = num_sgs;
1286         sg_init_table(urb->sg, urb->num_sgs + 1);
1287
1288         sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1289         total_len += skb_headlen(skb);
1290
1291         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1292                 struct skb_frag_struct *f = &skb_shinfo(skb)->frags[i];
1293
1294                 total_len += skb_frag_size(f);
1295                 sg_set_page(&urb->sg[i + s], f->page.p, f->size,
1296                                 f->page_offset);
1297         }
1298         urb->transfer_buffer_length = total_len;
1299
1300         return 1;
1301 }
1302
1303 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1304                                      struct net_device *net)
1305 {
1306         struct usbnet           *dev = netdev_priv(net);
1307         unsigned int                    length;
1308         struct urb              *urb = NULL;
1309         struct skb_data         *entry;
1310         struct driver_info      *info = dev->driver_info;
1311         unsigned long           flags;
1312         int retval;
1313
1314         if (skb)
1315                 skb_tx_timestamp(skb);
1316
1317         // some devices want funky USB-level framing, for
1318         // win32 driver (usually) and/or hardware quirks
1319         if (info->tx_fixup) {
1320                 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1321                 if (!skb) {
1322                         /* packet collected; minidriver waiting for more */
1323                         if (info->flags & FLAG_MULTI_PACKET)
1324                                 goto not_drop;
1325                         netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1326                         goto drop;
1327                 }
1328         }
1329
1330         if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1331                 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1332                 goto drop;
1333         }
1334
1335         entry = (struct skb_data *) skb->cb;
1336         entry->urb = urb;
1337         entry->dev = dev;
1338
1339         usb_fill_bulk_urb (urb, dev->udev, dev->out,
1340                         skb->data, skb->len, tx_complete, skb);
1341         if (dev->can_dma_sg) {
1342                 if (build_dma_sg(skb, urb) < 0)
1343                         goto drop;
1344         }
1345         length = urb->transfer_buffer_length;
1346
1347         /* don't assume the hardware handles USB_ZERO_PACKET
1348          * NOTE:  strictly conforming cdc-ether devices should expect
1349          * the ZLP here, but ignore the one-byte packet.
1350          * NOTE2: CDC NCM specification is different from CDC ECM when
1351          * handling ZLP/short packets, so cdc_ncm driver will make short
1352          * packet itself if needed.
1353          */
1354         if (length % dev->maxpacket == 0) {
1355                 if (!(info->flags & FLAG_SEND_ZLP)) {
1356                         if (!(info->flags & FLAG_MULTI_PACKET)) {
1357                                 length++;
1358                                 if (skb_tailroom(skb) && !urb->num_sgs) {
1359                                         skb->data[skb->len] = 0;
1360                                         __skb_put(skb, 1);
1361                                 } else if (urb->num_sgs)
1362                                         sg_set_buf(&urb->sg[urb->num_sgs++],
1363                                                         dev->padding_pkt, 1);
1364                         }
1365                 } else
1366                         urb->transfer_flags |= URB_ZERO_PACKET;
1367         }
1368         urb->transfer_buffer_length = length;
1369
1370         if (info->flags & FLAG_MULTI_PACKET) {
1371                 /* Driver has set number of packets and a length delta.
1372                  * Calculate the complete length and ensure that it's
1373                  * positive.
1374                  */
1375                 entry->length += length;
1376                 if (WARN_ON_ONCE(entry->length <= 0))
1377                         entry->length = length;
1378         } else {
1379                 usbnet_set_skb_tx_stats(skb, 1, length);
1380         }
1381
1382         spin_lock_irqsave(&dev->txq.lock, flags);
1383         retval = usb_autopm_get_interface_async(dev->intf);
1384         if (retval < 0) {
1385                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1386                 goto drop;
1387         }
1388
1389 #ifdef CONFIG_PM
1390         /* if this triggers the device is still a sleep */
1391         if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1392                 /* transmission will be done in resume */
1393                 usb_anchor_urb(urb, &dev->deferred);
1394                 /* no use to process more packets */
1395                 netif_stop_queue(net);
1396                 usb_put_urb(urb);
1397                 spin_unlock_irqrestore(&dev->txq.lock, flags);
1398                 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1399                 goto deferred;
1400         }
1401 #endif
1402
1403         switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1404         case -EPIPE:
1405                 netif_stop_queue (net);
1406                 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1407                 usb_autopm_put_interface_async(dev->intf);
1408                 break;
1409         default:
1410                 usb_autopm_put_interface_async(dev->intf);
1411                 netif_dbg(dev, tx_err, dev->net,
1412                           "tx: submit urb err %d\n", retval);
1413                 break;
1414         case 0:
1415                 net->trans_start = jiffies;
1416                 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1417                 if (dev->txq.qlen >= TX_QLEN (dev))
1418                         netif_stop_queue (net);
1419         }
1420         spin_unlock_irqrestore (&dev->txq.lock, flags);
1421
1422         if (retval) {
1423                 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1424 drop:
1425                 dev->net->stats.tx_dropped++;
1426 not_drop:
1427                 if (skb)
1428                         dev_kfree_skb_any (skb);
1429                 if (urb) {
1430                         kfree(urb->sg);
1431                         usb_free_urb(urb);
1432                 }
1433         } else
1434                 netif_dbg(dev, tx_queued, dev->net,
1435                           "> tx, len %u, type 0x%x\n", length, skb->protocol);
1436 #ifdef CONFIG_PM
1437 deferred:
1438 #endif
1439         return NETDEV_TX_OK;
1440 }
1441 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1442
1443 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1444 {
1445         struct urb      *urb;
1446         int             i;
1447         int             ret = 0;
1448
1449         /* don't refill the queue all at once */
1450         for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1451                 urb = usb_alloc_urb(0, flags);
1452                 if (urb != NULL) {
1453                         ret = rx_submit(dev, urb, flags);
1454                         if (ret)
1455                                 goto err;
1456                 } else {
1457                         ret = -ENOMEM;
1458                         goto err;
1459                 }
1460         }
1461 err:
1462         return ret;
1463 }
1464
1465 /*-------------------------------------------------------------------------*/
1466
1467 // tasklet (work deferred from completions, in_irq) or timer
1468
1469 static void usbnet_bh (unsigned long param)
1470 {
1471         struct usbnet           *dev = (struct usbnet *) param;
1472         struct sk_buff          *skb;
1473         struct skb_data         *entry;
1474
1475         while ((skb = skb_dequeue (&dev->done))) {
1476                 entry = (struct skb_data *) skb->cb;
1477                 switch (entry->state) {
1478                 case rx_done:
1479                         entry->state = rx_cleanup;
1480                         rx_process (dev, skb);
1481                         continue;
1482                 case tx_done:
1483                         kfree(entry->urb->sg);
1484                 case rx_cleanup:
1485                         usb_free_urb (entry->urb);
1486                         dev_kfree_skb (skb);
1487                         continue;
1488                 default:
1489                         netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1490                 }
1491         }
1492
1493         /* restart RX again after disabling due to high error rate */
1494         clear_bit(EVENT_RX_KILL, &dev->flags);
1495
1496         /* waiting for all pending urbs to complete?
1497          * only then can we forgo submitting anew
1498          */
1499         if (waitqueue_active(&dev->wait)) {
1500                 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1501                         wake_up_all(&dev->wait);
1502
1503         // or are we maybe short a few urbs?
1504         } else if (netif_running (dev->net) &&
1505                    netif_device_present (dev->net) &&
1506                    netif_carrier_ok(dev->net) &&
1507                    !timer_pending (&dev->delay) &&
1508                    !test_bit (EVENT_RX_HALT, &dev->flags)) {
1509                 int     temp = dev->rxq.qlen;
1510
1511                 if (temp < RX_QLEN(dev)) {
1512                         if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1513                                 return;
1514                         if (temp != dev->rxq.qlen)
1515                                 netif_dbg(dev, link, dev->net,
1516                                           "rxqlen %d --> %d\n",
1517                                           temp, dev->rxq.qlen);
1518                         if (dev->rxq.qlen < RX_QLEN(dev))
1519                                 tasklet_schedule (&dev->bh);
1520                 }
1521                 if (dev->txq.qlen < TX_QLEN (dev))
1522                         netif_wake_queue (dev->net);
1523         }
1524 }
1525
1526
1527 /*-------------------------------------------------------------------------
1528  *
1529  * USB Device Driver support
1530  *
1531  *-------------------------------------------------------------------------*/
1532
1533 // precondition: never called in_interrupt
1534
1535 void usbnet_disconnect (struct usb_interface *intf)
1536 {
1537         struct usbnet           *dev;
1538         struct usb_device       *xdev;
1539         struct net_device       *net;
1540
1541         dev = usb_get_intfdata(intf);
1542         usb_set_intfdata(intf, NULL);
1543         if (!dev)
1544                 return;
1545
1546         xdev = interface_to_usbdev (intf);
1547
1548         netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1549                    intf->dev.driver->name,
1550                    xdev->bus->bus_name, xdev->devpath,
1551                    dev->driver_info->description);
1552
1553         net = dev->net;
1554         unregister_netdev (net);
1555
1556         cancel_work_sync(&dev->kevent);
1557
1558         usb_scuttle_anchored_urbs(&dev->deferred);
1559
1560         if (dev->driver_info->unbind)
1561                 dev->driver_info->unbind (dev, intf);
1562
1563         usb_kill_urb(dev->interrupt);
1564         usb_free_urb(dev->interrupt);
1565         kfree(dev->padding_pkt);
1566
1567         free_netdev(net);
1568 }
1569 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1570
1571 static const struct net_device_ops usbnet_netdev_ops = {
1572         .ndo_open               = usbnet_open,
1573         .ndo_stop               = usbnet_stop,
1574         .ndo_start_xmit         = usbnet_start_xmit,
1575         .ndo_tx_timeout         = usbnet_tx_timeout,
1576         .ndo_set_rx_mode        = usbnet_set_rx_mode,
1577         .ndo_change_mtu         = usbnet_change_mtu,
1578         .ndo_set_mac_address    = eth_mac_addr,
1579         .ndo_validate_addr      = eth_validate_addr,
1580 };
1581
1582 /*-------------------------------------------------------------------------*/
1583
1584 // precondition: never called in_interrupt
1585
1586 static struct device_type wlan_type = {
1587         .name   = "wlan",
1588 };
1589
1590 static struct device_type wwan_type = {
1591         .name   = "wwan",
1592 };
1593
1594 int
1595 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1596 {
1597         struct usbnet                   *dev;
1598         struct net_device               *net;
1599         struct usb_host_interface       *interface;
1600         struct driver_info              *info;
1601         struct usb_device               *xdev;
1602         int                             status;
1603         const char                      *name;
1604         struct usb_driver       *driver = to_usb_driver(udev->dev.driver);
1605
1606         /* usbnet already took usb runtime pm, so have to enable the feature
1607          * for usb interface, otherwise usb_autopm_get_interface may return
1608          * failure if RUNTIME_PM is enabled.
1609          */
1610         if (!driver->supports_autosuspend) {
1611                 driver->supports_autosuspend = 1;
1612                 pm_runtime_enable(&udev->dev);
1613         }
1614
1615         name = udev->dev.driver->name;
1616         info = (struct driver_info *) prod->driver_info;
1617         if (!info) {
1618                 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1619                 return -ENODEV;
1620         }
1621         xdev = interface_to_usbdev (udev);
1622         interface = udev->cur_altsetting;
1623
1624         status = -ENOMEM;
1625
1626         // set up our own records
1627         net = alloc_etherdev(sizeof(*dev));
1628         if (!net)
1629                 goto out;
1630
1631         /* netdev_printk() needs this so do it as early as possible */
1632         SET_NETDEV_DEV(net, &udev->dev);
1633
1634         dev = netdev_priv(net);
1635         dev->udev = xdev;
1636         dev->intf = udev;
1637         dev->driver_info = info;
1638         dev->driver_name = name;
1639         dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1640                                 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1641         init_waitqueue_head(&dev->wait);
1642         skb_queue_head_init (&dev->rxq);
1643         skb_queue_head_init (&dev->txq);
1644         skb_queue_head_init (&dev->done);
1645         skb_queue_head_init(&dev->rxq_pause);
1646         dev->bh.func = usbnet_bh;
1647         dev->bh.data = (unsigned long) dev;
1648         INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1649         init_usb_anchor(&dev->deferred);
1650         dev->delay.function = usbnet_bh;
1651         dev->delay.data = (unsigned long) dev;
1652         init_timer (&dev->delay);
1653         mutex_init (&dev->phy_mutex);
1654         mutex_init(&dev->interrupt_mutex);
1655         dev->interrupt_count = 0;
1656
1657         dev->net = net;
1658         strcpy (net->name, "usb%d");
1659         memcpy (net->dev_addr, node_id, sizeof node_id);
1660
1661         /* rx and tx sides can use different message sizes;
1662          * bind() should set rx_urb_size in that case.
1663          */
1664         dev->hard_mtu = net->mtu + net->hard_header_len;
1665 #if 0
1666 // dma_supported() is deeply broken on almost all architectures
1667         // possible with some EHCI controllers
1668         if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1669                 net->features |= NETIF_F_HIGHDMA;
1670 #endif
1671
1672         net->netdev_ops = &usbnet_netdev_ops;
1673         net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1674         net->ethtool_ops = &usbnet_ethtool_ops;
1675
1676         // allow device-specific bind/init procedures
1677         // NOTE net->name still not usable ...
1678         if (info->bind) {
1679                 status = info->bind (dev, udev);
1680                 if (status < 0)
1681                         goto out1;
1682
1683                 // heuristic:  "usb%d" for links we know are two-host,
1684                 // else "eth%d" when there's reasonable doubt.  userspace
1685                 // can rename the link if it knows better.
1686                 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1687                     ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1688                      (net->dev_addr [0] & 0x02) == 0))
1689                         strcpy (net->name, "eth%d");
1690                 /* WLAN devices should always be named "wlan%d" */
1691                 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1692                         strcpy(net->name, "wlan%d");
1693                 /* WWAN devices should always be named "wwan%d" */
1694                 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1695                         strcpy(net->name, "wwan%d");
1696
1697                 /* devices that cannot do ARP */
1698                 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1699                         net->flags |= IFF_NOARP;
1700
1701                 /* maybe the remote can't receive an Ethernet MTU */
1702                 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1703                         net->mtu = dev->hard_mtu - net->hard_header_len;
1704         } else if (!info->in || !info->out)
1705                 status = usbnet_get_endpoints (dev, udev);
1706         else {
1707                 dev->in = usb_rcvbulkpipe (xdev, info->in);
1708                 dev->out = usb_sndbulkpipe (xdev, info->out);
1709                 if (!(info->flags & FLAG_NO_SETINT))
1710                         status = usb_set_interface (xdev,
1711                                 interface->desc.bInterfaceNumber,
1712                                 interface->desc.bAlternateSetting);
1713                 else
1714                         status = 0;
1715
1716         }
1717         if (status >= 0 && dev->status)
1718                 status = init_status (dev, udev);
1719         if (status < 0)
1720                 goto out3;
1721
1722         if (!dev->rx_urb_size)
1723                 dev->rx_urb_size = dev->hard_mtu;
1724         dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1725
1726         /* let userspace know we have a random address */
1727         if (ether_addr_equal(net->dev_addr, node_id))
1728                 net->addr_assign_type = NET_ADDR_RANDOM;
1729
1730         if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1731                 SET_NETDEV_DEVTYPE(net, &wlan_type);
1732         if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1733                 SET_NETDEV_DEVTYPE(net, &wwan_type);
1734
1735         /* initialize max rx_qlen and tx_qlen */
1736         usbnet_update_max_qlen(dev);
1737
1738         if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1739                 !(info->flags & FLAG_MULTI_PACKET)) {
1740                 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1741                 if (!dev->padding_pkt) {
1742                         status = -ENOMEM;
1743                         goto out4;
1744                 }
1745         }
1746
1747         status = register_netdev (net);
1748         if (status)
1749                 goto out5;
1750         netif_info(dev, probe, dev->net,
1751                    "register '%s' at usb-%s-%s, %s, %pM\n",
1752                    udev->dev.driver->name,
1753                    xdev->bus->bus_name, xdev->devpath,
1754                    dev->driver_info->description,
1755                    net->dev_addr);
1756
1757         // ok, it's ready to go.
1758         usb_set_intfdata (udev, dev);
1759
1760         netif_device_attach (net);
1761
1762         if (dev->driver_info->flags & FLAG_LINK_INTR)
1763                 usbnet_link_change(dev, 0, 0);
1764
1765         return 0;
1766
1767 out5:
1768         kfree(dev->padding_pkt);
1769 out4:
1770         usb_free_urb(dev->interrupt);
1771 out3:
1772         if (info->unbind)
1773                 info->unbind (dev, udev);
1774 out1:
1775         free_netdev(net);
1776 out:
1777         return status;
1778 }
1779 EXPORT_SYMBOL_GPL(usbnet_probe);
1780
1781 /*-------------------------------------------------------------------------*/
1782
1783 /*
1784  * suspend the whole driver as soon as the first interface is suspended
1785  * resume only when the last interface is resumed
1786  */
1787
1788 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1789 {
1790         struct usbnet           *dev = usb_get_intfdata(intf);
1791
1792         if (!dev->suspend_count++) {
1793                 spin_lock_irq(&dev->txq.lock);
1794                 /* don't autosuspend while transmitting */
1795                 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1796                         dev->suspend_count--;
1797                         spin_unlock_irq(&dev->txq.lock);
1798                         return -EBUSY;
1799                 } else {
1800                         set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1801                         spin_unlock_irq(&dev->txq.lock);
1802                 }
1803                 /*
1804                  * accelerate emptying of the rx and queues, to avoid
1805                  * having everything error out.
1806                  */
1807                 netif_device_detach (dev->net);
1808                 usbnet_terminate_urbs(dev);
1809                 __usbnet_status_stop_force(dev);
1810
1811                 /*
1812                  * reattach so runtime management can use and
1813                  * wake the device
1814                  */
1815                 netif_device_attach (dev->net);
1816         }
1817         return 0;
1818 }
1819 EXPORT_SYMBOL_GPL(usbnet_suspend);
1820
1821 int usbnet_resume (struct usb_interface *intf)
1822 {
1823         struct usbnet           *dev = usb_get_intfdata(intf);
1824         struct sk_buff          *skb;
1825         struct urb              *res;
1826         int                     retval;
1827
1828         if (!--dev->suspend_count) {
1829                 /* resume interrupt URB if it was previously submitted */
1830                 __usbnet_status_start_force(dev, GFP_NOIO);
1831
1832                 spin_lock_irq(&dev->txq.lock);
1833                 while ((res = usb_get_from_anchor(&dev->deferred))) {
1834
1835                         skb = (struct sk_buff *)res->context;
1836                         retval = usb_submit_urb(res, GFP_ATOMIC);
1837                         if (retval < 0) {
1838                                 dev_kfree_skb_any(skb);
1839                                 kfree(res->sg);
1840                                 usb_free_urb(res);
1841                                 usb_autopm_put_interface_async(dev->intf);
1842                         } else {
1843                                 dev->net->trans_start = jiffies;
1844                                 __skb_queue_tail(&dev->txq, skb);
1845                         }
1846                 }
1847
1848                 smp_mb();
1849                 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1850                 spin_unlock_irq(&dev->txq.lock);
1851
1852                 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1853                         /* handle remote wakeup ASAP
1854                          * we cannot race against stop
1855                          */
1856                         if (netif_device_present(dev->net) &&
1857                                 !timer_pending(&dev->delay) &&
1858                                 !test_bit(EVENT_RX_HALT, &dev->flags))
1859                                         rx_alloc_submit(dev, GFP_NOIO);
1860
1861                         if (!(dev->txq.qlen >= TX_QLEN(dev)))
1862                                 netif_tx_wake_all_queues(dev->net);
1863                         tasklet_schedule (&dev->bh);
1864                 }
1865         }
1866
1867         if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1868                 usb_autopm_get_interface_no_resume(intf);
1869
1870         return 0;
1871 }
1872 EXPORT_SYMBOL_GPL(usbnet_resume);
1873
1874 /*
1875  * Either a subdriver implements manage_power, then it is assumed to always
1876  * be ready to be suspended or it reports the readiness to be suspended
1877  * explicitly
1878  */
1879 void usbnet_device_suggests_idle(struct usbnet *dev)
1880 {
1881         if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1882                 dev->intf->needs_remote_wakeup = 1;
1883                 usb_autopm_put_interface_async(dev->intf);
1884         }
1885 }
1886 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1887
1888 /*
1889  * For devices that can do without special commands
1890  */
1891 int usbnet_manage_power(struct usbnet *dev, int on)
1892 {
1893         dev->intf->needs_remote_wakeup = on;
1894         return 0;
1895 }
1896 EXPORT_SYMBOL(usbnet_manage_power);
1897
1898 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1899 {
1900         /* update link after link is reseted */
1901         if (link && !need_reset)
1902                 netif_carrier_on(dev->net);
1903         else
1904                 netif_carrier_off(dev->net);
1905
1906         if (need_reset && link)
1907                 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1908         else
1909                 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1910 }
1911 EXPORT_SYMBOL(usbnet_link_change);
1912
1913 /*-------------------------------------------------------------------------*/
1914 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1915                              u16 value, u16 index, void *data, u16 size)
1916 {
1917         void *buf = NULL;
1918         int err = -ENOMEM;
1919
1920         netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
1921                    " value=0x%04x index=0x%04x size=%d\n",
1922                    cmd, reqtype, value, index, size);
1923
1924         if (data) {
1925                 buf = kmalloc(size, GFP_KERNEL);
1926                 if (!buf)
1927                         goto out;
1928         }
1929
1930         err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
1931                               cmd, reqtype, value, index, buf, size,
1932                               USB_CTRL_GET_TIMEOUT);
1933         if (err > 0 && err <= size)
1934                 memcpy(data, buf, err);
1935         kfree(buf);
1936 out:
1937         return err;
1938 }
1939
1940 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1941                               u16 value, u16 index, const void *data,
1942                               u16 size)
1943 {
1944         void *buf = NULL;
1945         int err = -ENOMEM;
1946
1947         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
1948                    " value=0x%04x index=0x%04x size=%d\n",
1949                    cmd, reqtype, value, index, size);
1950
1951         if (data) {
1952                 buf = kmemdup(data, size, GFP_KERNEL);
1953                 if (!buf)
1954                         goto out;
1955         }
1956
1957         err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
1958                               cmd, reqtype, value, index, buf, size,
1959                               USB_CTRL_SET_TIMEOUT);
1960         kfree(buf);
1961
1962 out:
1963         return err;
1964 }
1965
1966 int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr,
1967                                 struct usb_interface *intf,
1968                                 u8 *buffer,
1969                                 int buflen)
1970 {
1971         /* duplicates are ignored */
1972         struct usb_cdc_union_desc *union_header = NULL;
1973
1974         /* duplicates are not tolerated */
1975         struct usb_cdc_header_desc *header = NULL;
1976         struct usb_cdc_ether_desc *ether = NULL;
1977         struct usb_cdc_mdlm_detail_desc *detail = NULL;
1978         struct usb_cdc_mdlm_desc *desc = NULL;
1979
1980         unsigned int elength;
1981         int cnt = 0;
1982
1983         memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header));
1984         hdr->phonet_magic_present = false;
1985         while (buflen > 0) {
1986                 elength = buffer[0];
1987                 if (!elength) {
1988                         dev_err(&intf->dev, "skipping garbage byte\n");
1989                         elength = 1;
1990                         goto next_desc;
1991                 }
1992                 if (buffer[1] != USB_DT_CS_INTERFACE) {
1993                         dev_err(&intf->dev, "skipping garbage\n");
1994                         goto next_desc;
1995                 }
1996
1997                 switch (buffer[2]) {
1998                 case USB_CDC_UNION_TYPE: /* we've found it */
1999                         if (elength < sizeof(struct usb_cdc_union_desc))
2000                                 goto next_desc;
2001                         if (union_header) {
2002                                 dev_err(&intf->dev, "More than one union descriptor, skipping ...\n");
2003                                 goto next_desc;
2004                         }
2005                         union_header = (struct usb_cdc_union_desc *)buffer;
2006                         break;
2007                 case USB_CDC_COUNTRY_TYPE:
2008                         if (elength < sizeof(struct usb_cdc_country_functional_desc))
2009                                 goto next_desc;
2010                         hdr->usb_cdc_country_functional_desc =
2011                                 (struct usb_cdc_country_functional_desc *)buffer;
2012                         break;
2013                 case USB_CDC_HEADER_TYPE:
2014                         if (elength != sizeof(struct usb_cdc_header_desc))
2015                                 goto next_desc;
2016                         if (header)
2017                                 return -EINVAL;
2018                         header = (struct usb_cdc_header_desc *)buffer;
2019                         break;
2020                 case USB_CDC_ACM_TYPE:
2021                         if (elength < sizeof(struct usb_cdc_acm_descriptor))
2022                                 goto next_desc;
2023                         hdr->usb_cdc_acm_descriptor =
2024                                 (struct usb_cdc_acm_descriptor *)buffer;
2025                         break;
2026                 case USB_CDC_ETHERNET_TYPE:
2027                         if (elength != sizeof(struct usb_cdc_ether_desc))
2028                                 goto next_desc;
2029                         if (ether)
2030                                 return -EINVAL;
2031                         ether = (struct usb_cdc_ether_desc *)buffer;
2032                         break;
2033                 case USB_CDC_CALL_MANAGEMENT_TYPE:
2034                         if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor))
2035                                 goto next_desc;
2036                         hdr->usb_cdc_call_mgmt_descriptor =
2037                                 (struct usb_cdc_call_mgmt_descriptor *)buffer;
2038                         break;
2039                 case USB_CDC_DMM_TYPE:
2040                         if (elength < sizeof(struct usb_cdc_dmm_desc))
2041                                 goto next_desc;
2042                         hdr->usb_cdc_dmm_desc =
2043                                 (struct usb_cdc_dmm_desc *)buffer;
2044                         break;
2045                 case USB_CDC_MDLM_TYPE:
2046                         if (elength < sizeof(struct usb_cdc_mdlm_desc *))
2047                                 goto next_desc;
2048                         if (desc)
2049                                 return -EINVAL;
2050                         desc = (struct usb_cdc_mdlm_desc *)buffer;
2051                         break;
2052                 case USB_CDC_MDLM_DETAIL_TYPE:
2053                         if (elength < sizeof(struct usb_cdc_mdlm_detail_desc *))
2054                                 goto next_desc;
2055                         if (detail)
2056                                 return -EINVAL;
2057                         detail = (struct usb_cdc_mdlm_detail_desc *)buffer;
2058                         break;
2059                 case USB_CDC_NCM_TYPE:
2060                         if (elength < sizeof(struct usb_cdc_ncm_desc))
2061                                 goto next_desc;
2062                         hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer;
2063                         break;
2064                 case USB_CDC_MBIM_TYPE:
2065                         if (elength < sizeof(struct usb_cdc_mbim_desc))
2066                                 goto next_desc;
2067
2068                         hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer;
2069                         break;
2070                 case USB_CDC_MBIM_EXTENDED_TYPE:
2071                         if (elength < sizeof(struct usb_cdc_mbim_extended_desc))
2072                                 break;
2073                         hdr->usb_cdc_mbim_extended_desc =
2074                                 (struct usb_cdc_mbim_extended_desc *)buffer;
2075                         break;
2076                 case CDC_PHONET_MAGIC_NUMBER:
2077                         hdr->phonet_magic_present = true;
2078                         break;
2079                 default:
2080                         /*
2081                          * there are LOTS more CDC descriptors that
2082                          * could legitimately be found here.
2083                          */
2084                         dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n",
2085                                         buffer[2], elength);
2086                         goto next_desc;
2087                 }
2088                 cnt++;
2089 next_desc:
2090                 buflen -= elength;
2091                 buffer += elength;
2092         }
2093         hdr->usb_cdc_union_desc = union_header;
2094         hdr->usb_cdc_header_desc = header;
2095         hdr->usb_cdc_mdlm_detail_desc = detail;
2096         hdr->usb_cdc_mdlm_desc = desc;
2097         hdr->usb_cdc_ether_desc = ether;
2098         return cnt;
2099 }
2100
2101 EXPORT_SYMBOL(cdc_parse_cdc_header);
2102
2103 /*
2104  * The function can't be called inside suspend/resume callback,
2105  * otherwise deadlock will be caused.
2106  */
2107 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2108                     u16 value, u16 index, void *data, u16 size)
2109 {
2110         int ret;
2111
2112         if (usb_autopm_get_interface(dev->intf) < 0)
2113                 return -ENODEV;
2114         ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2115                                 data, size);
2116         usb_autopm_put_interface(dev->intf);
2117         return ret;
2118 }
2119 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2120
2121 /*
2122  * The function can't be called inside suspend/resume callback,
2123  * otherwise deadlock will be caused.
2124  */
2125 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2126                      u16 value, u16 index, const void *data, u16 size)
2127 {
2128         int ret;
2129
2130         if (usb_autopm_get_interface(dev->intf) < 0)
2131                 return -ENODEV;
2132         ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2133                                  data, size);
2134         usb_autopm_put_interface(dev->intf);
2135         return ret;
2136 }
2137 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2138
2139 /*
2140  * The function can be called inside suspend/resume callback safely
2141  * and should only be called by suspend/resume callback generally.
2142  */
2143 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2144                           u16 value, u16 index, void *data, u16 size)
2145 {
2146         return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2147                                  data, size);
2148 }
2149 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2150
2151 /*
2152  * The function can be called inside suspend/resume callback safely
2153  * and should only be called by suspend/resume callback generally.
2154  */
2155 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2156                           u16 value, u16 index, const void *data,
2157                           u16 size)
2158 {
2159         return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2160                                   data, size);
2161 }
2162 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2163
2164 static void usbnet_async_cmd_cb(struct urb *urb)
2165 {
2166         struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2167         int status = urb->status;
2168
2169         if (status < 0)
2170                 dev_dbg(&urb->dev->dev, "%s failed with %d",
2171                         __func__, status);
2172
2173         kfree(req);
2174         usb_free_urb(urb);
2175 }
2176
2177 /*
2178  * The caller must make sure that device can't be put into suspend
2179  * state until the control URB completes.
2180  */
2181 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2182                            u16 value, u16 index, const void *data, u16 size)
2183 {
2184         struct usb_ctrlrequest *req = NULL;
2185         struct urb *urb;
2186         int err = -ENOMEM;
2187         void *buf = NULL;
2188
2189         netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2190                    " value=0x%04x index=0x%04x size=%d\n",
2191                    cmd, reqtype, value, index, size);
2192
2193         urb = usb_alloc_urb(0, GFP_ATOMIC);
2194         if (!urb) {
2195                 netdev_err(dev->net, "Error allocating URB in"
2196                            " %s!\n", __func__);
2197                 goto fail;
2198         }
2199
2200         if (data) {
2201                 buf = kmemdup(data, size, GFP_ATOMIC);
2202                 if (!buf) {
2203                         netdev_err(dev->net, "Error allocating buffer"
2204                                    " in %s!\n", __func__);
2205                         goto fail_free;
2206                 }
2207         }
2208
2209         req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2210         if (!req)
2211                 goto fail_free_buf;
2212
2213         req->bRequestType = reqtype;
2214         req->bRequest = cmd;
2215         req->wValue = cpu_to_le16(value);
2216         req->wIndex = cpu_to_le16(index);
2217         req->wLength = cpu_to_le16(size);
2218
2219         usb_fill_control_urb(urb, dev->udev,
2220                              usb_sndctrlpipe(dev->udev, 0),
2221                              (void *)req, buf, size,
2222                              usbnet_async_cmd_cb, req);
2223         urb->transfer_flags |= URB_FREE_BUFFER;
2224
2225         err = usb_submit_urb(urb, GFP_ATOMIC);
2226         if (err < 0) {
2227                 netdev_err(dev->net, "Error submitting the control"
2228                            " message: status=%d\n", err);
2229                 goto fail_free;
2230         }
2231         return 0;
2232
2233 fail_free_buf:
2234         kfree(buf);
2235 fail_free:
2236         kfree(req);
2237         usb_free_urb(urb);
2238 fail:
2239         return err;
2240
2241 }
2242 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2243 /*-------------------------------------------------------------------------*/
2244
2245 static int __init usbnet_init(void)
2246 {
2247         /* Compiler should optimize this out. */
2248         BUILD_BUG_ON(
2249                 FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
2250
2251         eth_random_addr(node_id);
2252         return 0;
2253 }
2254 module_init(usbnet_init);
2255
2256 static void __exit usbnet_exit(void)
2257 {
2258 }
2259 module_exit(usbnet_exit);
2260
2261 MODULE_AUTHOR("David Brownell");
2262 MODULE_DESCRIPTION("USB network driver framework");
2263 MODULE_LICENSE("GPL");