1 /*
2 * USB Network driver infrastructure
3 * Copyright (C) 2000-2005 by David Brownell
4 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21 /*
22 * This is a generic "USB networking" framework that works with several
23 * kinds of full and high speed networking devices: host-to-host cables,
24 * smart usb peripherals, and actual Ethernet adapters.
25 *
26 * These devices usually differ in terms of control protocols (if they
27 * even have one!) and sometimes they define new framing to wrap or batch
28 * Ethernet packets. Otherwise, they talk to USB pretty much the same,
29 * so interface (un)binding, endpoint I/O queues, fault handling, and other
30 * issues can usefully be addressed by this framework.
31 */
32
33 // #define DEBUG // error path messages, extra info
34 // #define VERBOSE // more; success messages
35
36 #include <linux/module.h>
37 #include <linux/init.h>
38 #include <linux/netdevice.h>
39 #include <linux/etherdevice.h>
40 #include <linux/ethtool.h>
41 #include <linux/workqueue.h>
42 #include <linux/mii.h>
43 #include <linux/usb.h>
44 #include <linux/usb/usbnet.h>
45
46 #define DRIVER_VERSION "22-Aug-2005"
47
48
49 /*-------------------------------------------------------------------------*/
50
51 /*
52 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
53 * Several dozen bytes of IPv4 data can fit in two such transactions.
54 * One maximum size Ethernet packet takes twenty four of them.
55 * For high speed, each frame comfortably fits almost 36 max size
56 * Ethernet packets (so queues should be bigger).
57 *
58 * REVISIT qlens should be members of 'struct usbnet'; the goal is to
59 * let the USB host controller be busy for 5msec or more before an irq
60 * is required, under load. Jumbograms change the equation.
61 */
62 #define RX_MAX_QUEUE_MEMORY (60 * 1518)
63 #define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
64 (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
65 #define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
66 (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
67
68 // reawaken network queue this soon after stopping; else watchdog barks
69 #define TX_TIMEOUT_JIFFIES (5*HZ)
70
71 // throttle rx/tx briefly after some faults, so khubd might disconnect()
72 // us (it polls at HZ/4 usually) before we report too many false errors.
73 #define THROTTLE_JIFFIES (HZ/8)
74
75 // between wakeups
76 #define UNLINK_TIMEOUT_MS 3
77
78 /*-------------------------------------------------------------------------*/
79
80 // randomly generated ethernet address
81 static u8 node_id [ETH_ALEN];
82
83 static const char driver_name [] = "usbnet";
84
85 /* use ethtool to change the level for any given device */
86 static int msg_level = -1;
87 module_param (msg_level, int, 0);
88 MODULE_PARM_DESC (msg_level, "Override default message level");
89
90 /*-------------------------------------------------------------------------*/
91
92 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)93 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
94 {
95 int tmp;
96 struct usb_host_interface *alt = NULL;
97 struct usb_host_endpoint *in = NULL, *out = NULL;
98 struct usb_host_endpoint *status = NULL;
99
100 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
101 unsigned ep;
102
103 in = out = status = NULL;
104 alt = intf->altsetting + tmp;
105
106 /* take the first altsetting with in-bulk + out-bulk;
107 * remember any status endpoint, just in case;
108 * ignore other endpoints and altsetttings.
109 */
110 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
111 struct usb_host_endpoint *e;
112 int intr = 0;
113
114 e = alt->endpoint + ep;
115 switch (e->desc.bmAttributes) {
116 case USB_ENDPOINT_XFER_INT:
117 if (!usb_endpoint_dir_in(&e->desc))
118 continue;
119 intr = 1;
120 /* FALLTHROUGH */
121 case USB_ENDPOINT_XFER_BULK:
122 break;
123 default:
124 continue;
125 }
126 if (usb_endpoint_dir_in(&e->desc)) {
127 if (!intr && !in)
128 in = e;
129 else if (intr && !status)
130 status = e;
131 } else {
132 if (!out)
133 out = e;
134 }
135 }
136 if (in && out)
137 break;
138 }
139 if (!alt || !in || !out)
140 return -EINVAL;
141
142 if (alt->desc.bAlternateSetting != 0
143 || !(dev->driver_info->flags & FLAG_NO_SETINT)) {
144 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
145 alt->desc.bAlternateSetting);
146 if (tmp < 0)
147 return tmp;
148 }
149
150 dev->in = usb_rcvbulkpipe (dev->udev,
151 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
152 dev->out = usb_sndbulkpipe (dev->udev,
153 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
154 dev->status = status;
155 return 0;
156 }
157 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
158
159 static void intr_complete (struct urb *urb);
160
init_status(struct usbnet * dev,struct usb_interface * intf)161 static int init_status (struct usbnet *dev, struct usb_interface *intf)
162 {
163 char *buf = NULL;
164 unsigned pipe = 0;
165 unsigned maxp;
166 unsigned period;
167
168 if (!dev->driver_info->status)
169 return 0;
170
171 pipe = usb_rcvintpipe (dev->udev,
172 dev->status->desc.bEndpointAddress
173 & USB_ENDPOINT_NUMBER_MASK);
174 maxp = usb_maxpacket (dev->udev, pipe, 0);
175
176 /* avoid 1 msec chatter: min 8 msec poll rate */
177 period = max ((int) dev->status->desc.bInterval,
178 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
179
180 buf = kmalloc (maxp, GFP_KERNEL);
181 if (buf) {
182 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
183 if (!dev->interrupt) {
184 kfree (buf);
185 return -ENOMEM;
186 } else {
187 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
188 buf, maxp, intr_complete, dev, period);
189 dev_dbg(&intf->dev,
190 "status ep%din, %d bytes period %d\n",
191 usb_pipeendpoint(pipe), maxp, period);
192 }
193 }
194 return 0;
195 }
196
197 /* Passes this packet up the stack, updating its accounting.
198 * Some link protocols batch packets, so their rx_fixup paths
199 * can return clones as well as just modify the original skb.
200 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)201 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
202 {
203 int status;
204
205 skb->protocol = eth_type_trans (skb, dev->net);
206 dev->stats.rx_packets++;
207 dev->stats.rx_bytes += skb->len;
208
209 if (netif_msg_rx_status (dev))
210 devdbg (dev, "< rx, len %zu, type 0x%x",
211 skb->len + sizeof (struct ethhdr), skb->protocol);
212 memset (skb->cb, 0, sizeof (struct skb_data));
213 status = netif_rx (skb);
214 if (status != NET_RX_SUCCESS && netif_msg_rx_err (dev))
215 devdbg (dev, "netif_rx status %d", status);
216 }
217 EXPORT_SYMBOL_GPL(usbnet_skb_return);
218
219
220 /*-------------------------------------------------------------------------
221 *
222 * Network Device Driver (peer link to "Host Device", from USB host)
223 *
224 *-------------------------------------------------------------------------*/
225
usbnet_change_mtu(struct net_device * net,int new_mtu)226 static int usbnet_change_mtu (struct net_device *net, int new_mtu)
227 {
228 struct usbnet *dev = netdev_priv(net);
229 int ll_mtu = new_mtu + net->hard_header_len;
230 int old_hard_mtu = dev->hard_mtu;
231 int old_rx_urb_size = dev->rx_urb_size;
232
233 if (new_mtu <= 0)
234 return -EINVAL;
235 // no second zero-length packet read wanted after mtu-sized packets
236 if ((ll_mtu % dev->maxpacket) == 0)
237 return -EDOM;
238 net->mtu = new_mtu;
239
240 dev->hard_mtu = net->mtu + net->hard_header_len;
241 if (dev->rx_urb_size == old_hard_mtu) {
242 dev->rx_urb_size = dev->hard_mtu;
243 if (dev->rx_urb_size > old_rx_urb_size)
244 usbnet_unlink_rx_urbs(dev);
245 }
246
247 return 0;
248 }
249
250 /*-------------------------------------------------------------------------*/
251
usbnet_get_stats(struct net_device * net)252 static struct net_device_stats *usbnet_get_stats (struct net_device *net)
253 {
254 struct usbnet *dev = netdev_priv(net);
255 return &dev->stats;
256 }
257
258 /*-------------------------------------------------------------------------*/
259
260 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
261 * completion callbacks. 2.5 should have fixed those bugs...
262 */
263
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list)264 static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
265 {
266 unsigned long flags;
267
268 spin_lock_irqsave(&list->lock, flags);
269 __skb_unlink(skb, list);
270 spin_unlock(&list->lock);
271 spin_lock(&dev->done.lock);
272 __skb_queue_tail(&dev->done, skb);
273 if (dev->done.qlen == 1)
274 tasklet_schedule(&dev->bh);
275 spin_unlock_irqrestore(&dev->done.lock, flags);
276 }
277
278 /* some work can't be done in tasklets, so we use keventd
279 *
280 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
281 * but tasklet_schedule() doesn't. hope the failure is rare.
282 */
usbnet_defer_kevent(struct usbnet * dev,int work)283 void usbnet_defer_kevent (struct usbnet *dev, int work)
284 {
285 set_bit (work, &dev->flags);
286 if (!schedule_work (&dev->kevent))
287 deverr (dev, "kevent %d may have been dropped", work);
288 else
289 devdbg (dev, "kevent %d scheduled", work);
290 }
291 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
292
293 /*-------------------------------------------------------------------------*/
294
295 static void rx_complete (struct urb *urb);
296
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)297 static void rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
298 {
299 struct sk_buff *skb;
300 struct skb_data *entry;
301 int retval = 0;
302 unsigned long lockflags;
303 size_t size = dev->rx_urb_size;
304
305 if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
306 if (netif_msg_rx_err (dev))
307 devdbg (dev, "no rx skb");
308 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
309 usb_free_urb (urb);
310 return;
311 }
312 skb_reserve (skb, NET_IP_ALIGN);
313
314 entry = (struct skb_data *) skb->cb;
315 entry->urb = urb;
316 entry->dev = dev;
317 entry->state = rx_start;
318 entry->length = 0;
319
320 usb_fill_bulk_urb (urb, dev->udev, dev->in,
321 skb->data, size, rx_complete, skb);
322
323 spin_lock_irqsave (&dev->rxq.lock, lockflags);
324
325 if (netif_running (dev->net)
326 && netif_device_present (dev->net)
327 && !test_bit (EVENT_RX_HALT, &dev->flags)) {
328 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
329 case -EPIPE:
330 usbnet_defer_kevent (dev, EVENT_RX_HALT);
331 break;
332 case -ENOMEM:
333 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
334 break;
335 case -ENODEV:
336 if (netif_msg_ifdown (dev))
337 devdbg (dev, "device gone");
338 netif_device_detach (dev->net);
339 break;
340 default:
341 if (netif_msg_rx_err (dev))
342 devdbg (dev, "rx submit, %d", retval);
343 tasklet_schedule (&dev->bh);
344 break;
345 case 0:
346 __skb_queue_tail (&dev->rxq, skb);
347 }
348 } else {
349 if (netif_msg_ifdown (dev))
350 devdbg (dev, "rx: stopped");
351 retval = -ENOLINK;
352 }
353 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
354 if (retval) {
355 dev_kfree_skb_any (skb);
356 usb_free_urb (urb);
357 }
358 }
359
360
361 /*-------------------------------------------------------------------------*/
362
rx_process(struct usbnet * dev,struct sk_buff * skb)363 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
364 {
365 if (dev->driver_info->rx_fixup
366 && !dev->driver_info->rx_fixup (dev, skb))
367 goto error;
368 // else network stack removes extra byte if we forced a short packet
369
370 if (skb->len)
371 usbnet_skb_return (dev, skb);
372 else {
373 if (netif_msg_rx_err (dev))
374 devdbg (dev, "drop");
375 error:
376 dev->stats.rx_errors++;
377 skb_queue_tail (&dev->done, skb);
378 }
379 }
380
381 /*-------------------------------------------------------------------------*/
382
rx_complete(struct urb * urb)383 static void rx_complete (struct urb *urb)
384 {
385 struct sk_buff *skb = (struct sk_buff *) urb->context;
386 struct skb_data *entry = (struct skb_data *) skb->cb;
387 struct usbnet *dev = entry->dev;
388 int urb_status = urb->status;
389
390 skb_put (skb, urb->actual_length);
391 entry->state = rx_done;
392 entry->urb = NULL;
393
394 switch (urb_status) {
395 /* success */
396 case 0:
397 if (skb->len < dev->net->hard_header_len) {
398 entry->state = rx_cleanup;
399 dev->stats.rx_errors++;
400 dev->stats.rx_length_errors++;
401 if (netif_msg_rx_err (dev))
402 devdbg (dev, "rx length %d", skb->len);
403 }
404 break;
405
406 /* stalls need manual reset. this is rare ... except that
407 * when going through USB 2.0 TTs, unplug appears this way.
408 * we avoid the highspeed version of the ETIMEOUT/EILSEQ
409 * storm, recovering as needed.
410 */
411 case -EPIPE:
412 dev->stats.rx_errors++;
413 usbnet_defer_kevent (dev, EVENT_RX_HALT);
414 // FALLTHROUGH
415
416 /* software-driven interface shutdown */
417 case -ECONNRESET: /* async unlink */
418 case -ESHUTDOWN: /* hardware gone */
419 if (netif_msg_ifdown (dev))
420 devdbg (dev, "rx shutdown, code %d", urb_status);
421 goto block;
422
423 /* we get controller i/o faults during khubd disconnect() delays.
424 * throttle down resubmits, to avoid log floods; just temporarily,
425 * so we still recover when the fault isn't a khubd delay.
426 */
427 case -EPROTO:
428 case -ETIME:
429 case -EILSEQ:
430 dev->stats.rx_errors++;
431 if (!timer_pending (&dev->delay)) {
432 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
433 if (netif_msg_link (dev))
434 devdbg (dev, "rx throttle %d", urb_status);
435 }
436 block:
437 entry->state = rx_cleanup;
438 entry->urb = urb;
439 urb = NULL;
440 break;
441
442 /* data overrun ... flush fifo? */
443 case -EOVERFLOW:
444 dev->stats.rx_over_errors++;
445 // FALLTHROUGH
446
447 default:
448 entry->state = rx_cleanup;
449 dev->stats.rx_errors++;
450 if (netif_msg_rx_err (dev))
451 devdbg (dev, "rx status %d", urb_status);
452 break;
453 }
454
455 defer_bh(dev, skb, &dev->rxq);
456
457 if (urb) {
458 if (netif_running (dev->net)
459 && !test_bit (EVENT_RX_HALT, &dev->flags)) {
460 rx_submit (dev, urb, GFP_ATOMIC);
461 return;
462 }
463 usb_free_urb (urb);
464 }
465 if (netif_msg_rx_err (dev))
466 devdbg (dev, "no read resubmitted");
467 }
468
intr_complete(struct urb * urb)469 static void intr_complete (struct urb *urb)
470 {
471 struct usbnet *dev = urb->context;
472 int status = urb->status;
473
474 switch (status) {
475 /* success */
476 case 0:
477 dev->driver_info->status(dev, urb);
478 break;
479
480 /* software-driven interface shutdown */
481 case -ENOENT: /* urb killed */
482 case -ESHUTDOWN: /* hardware gone */
483 if (netif_msg_ifdown (dev))
484 devdbg (dev, "intr shutdown, code %d", status);
485 return;
486
487 /* NOTE: not throttling like RX/TX, since this endpoint
488 * already polls infrequently
489 */
490 default:
491 devdbg (dev, "intr status %d", status);
492 break;
493 }
494
495 if (!netif_running (dev->net))
496 return;
497
498 memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
499 status = usb_submit_urb (urb, GFP_ATOMIC);
500 if (status != 0 && netif_msg_timer (dev))
501 deverr(dev, "intr resubmit --> %d", status);
502 }
503
504 /*-------------------------------------------------------------------------*/
505
506 // unlink pending rx/tx; completion handlers do all other cleanup
507
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)508 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
509 {
510 unsigned long flags;
511 struct sk_buff *skb, *skbnext;
512 int count = 0;
513
514 spin_lock_irqsave (&q->lock, flags);
515 skb_queue_walk_safe(q, skb, skbnext) {
516 struct skb_data *entry;
517 struct urb *urb;
518 int retval;
519
520 entry = (struct skb_data *) skb->cb;
521 urb = entry->urb;
522
523 // during some PM-driven resume scenarios,
524 // these (async) unlinks complete immediately
525 retval = usb_unlink_urb (urb);
526 if (retval != -EINPROGRESS && retval != 0)
527 devdbg (dev, "unlink urb err, %d", retval);
528 else
529 count++;
530 }
531 spin_unlock_irqrestore (&q->lock, flags);
532 return count;
533 }
534
535 // Flush all pending rx urbs
536 // minidrivers may need to do this when the MTU changes
537
usbnet_unlink_rx_urbs(struct usbnet * dev)538 void usbnet_unlink_rx_urbs(struct usbnet *dev)
539 {
540 if (netif_running(dev->net)) {
541 (void) unlink_urbs (dev, &dev->rxq);
542 tasklet_schedule(&dev->bh);
543 }
544 }
545 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
546
547 /*-------------------------------------------------------------------------*/
548
549 // precondition: never called in_interrupt
550
usbnet_stop(struct net_device * net)551 static int usbnet_stop (struct net_device *net)
552 {
553 struct usbnet *dev = netdev_priv(net);
554 int temp;
555 DECLARE_WAIT_QUEUE_HEAD_ONSTACK (unlink_wakeup);
556 DECLARE_WAITQUEUE (wait, current);
557
558 netif_stop_queue (net);
559
560 if (netif_msg_ifdown (dev))
561 devinfo (dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld",
562 dev->stats.rx_packets, dev->stats.tx_packets,
563 dev->stats.rx_errors, dev->stats.tx_errors
564 );
565
566 // ensure there are no more active urbs
567 add_wait_queue (&unlink_wakeup, &wait);
568 dev->wait = &unlink_wakeup;
569 temp = unlink_urbs (dev, &dev->txq) + unlink_urbs (dev, &dev->rxq);
570
571 // maybe wait for deletions to finish.
572 while (!skb_queue_empty(&dev->rxq)
573 && !skb_queue_empty(&dev->txq)
574 && !skb_queue_empty(&dev->done)) {
575 msleep(UNLINK_TIMEOUT_MS);
576 if (netif_msg_ifdown (dev))
577 devdbg (dev, "waited for %d urb completions", temp);
578 }
579 dev->wait = NULL;
580 remove_wait_queue (&unlink_wakeup, &wait);
581
582 usb_kill_urb(dev->interrupt);
583
584 /* deferred work (task, timer, softirq) must also stop.
585 * can't flush_scheduled_work() until we drop rtnl (later),
586 * else workers could deadlock; so make workers a NOP.
587 */
588 dev->flags = 0;
589 del_timer_sync (&dev->delay);
590 tasklet_kill (&dev->bh);
591 usb_autopm_put_interface(dev->intf);
592
593 return 0;
594 }
595
596 /*-------------------------------------------------------------------------*/
597
598 // posts reads, and enables write queuing
599
600 // precondition: never called in_interrupt
601
usbnet_open(struct net_device * net)602 static int usbnet_open (struct net_device *net)
603 {
604 struct usbnet *dev = netdev_priv(net);
605 int retval;
606 struct driver_info *info = dev->driver_info;
607
608 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
609 if (netif_msg_ifup (dev))
610 devinfo (dev,
611 "resumption fail (%d) usbnet usb-%s-%s, %s",
612 retval,
613 dev->udev->bus->bus_name, dev->udev->devpath,
614 info->description);
615 goto done_nopm;
616 }
617
618 // put into "known safe" state
619 if (info->reset && (retval = info->reset (dev)) < 0) {
620 if (netif_msg_ifup (dev))
621 devinfo (dev,
622 "open reset fail (%d) usbnet usb-%s-%s, %s",
623 retval,
624 dev->udev->bus->bus_name, dev->udev->devpath,
625 info->description);
626 goto done;
627 }
628
629 // insist peer be connected
630 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
631 if (netif_msg_ifup (dev))
632 devdbg (dev, "can't open; %d", retval);
633 goto done;
634 }
635
636 /* start any status interrupt transfer */
637 if (dev->interrupt) {
638 retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
639 if (retval < 0) {
640 if (netif_msg_ifup (dev))
641 deverr (dev, "intr submit %d", retval);
642 goto done;
643 }
644 }
645
646 netif_start_queue (net);
647 if (netif_msg_ifup (dev)) {
648 char *framing;
649
650 if (dev->driver_info->flags & FLAG_FRAMING_NC)
651 framing = "NetChip";
652 else if (dev->driver_info->flags & FLAG_FRAMING_GL)
653 framing = "GeneSys";
654 else if (dev->driver_info->flags & FLAG_FRAMING_Z)
655 framing = "Zaurus";
656 else if (dev->driver_info->flags & FLAG_FRAMING_RN)
657 framing = "RNDIS";
658 else if (dev->driver_info->flags & FLAG_FRAMING_AX)
659 framing = "ASIX";
660 else
661 framing = "simple";
662
663 devinfo (dev, "open: enable queueing "
664 "(rx %d, tx %d) mtu %d %s framing",
665 (int)RX_QLEN (dev), (int)TX_QLEN (dev), dev->net->mtu,
666 framing);
667 }
668
669 // delay posting reads until we're fully open
670 tasklet_schedule (&dev->bh);
671 return retval;
672 done:
673 usb_autopm_put_interface(dev->intf);
674 done_nopm:
675 return retval;
676 }
677
678 /*-------------------------------------------------------------------------*/
679
680 /* ethtool methods; minidrivers may need to add some more, but
681 * they'll probably want to use this base set.
682 */
683
usbnet_get_settings(struct net_device * net,struct ethtool_cmd * cmd)684 int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
685 {
686 struct usbnet *dev = netdev_priv(net);
687
688 if (!dev->mii.mdio_read)
689 return -EOPNOTSUPP;
690
691 return mii_ethtool_gset(&dev->mii, cmd);
692 }
693 EXPORT_SYMBOL_GPL(usbnet_get_settings);
694
usbnet_set_settings(struct net_device * net,struct ethtool_cmd * cmd)695 int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
696 {
697 struct usbnet *dev = netdev_priv(net);
698 int retval;
699
700 if (!dev->mii.mdio_write)
701 return -EOPNOTSUPP;
702
703 retval = mii_ethtool_sset(&dev->mii, cmd);
704
705 /* link speed/duplex might have changed */
706 if (dev->driver_info->link_reset)
707 dev->driver_info->link_reset(dev);
708
709 return retval;
710
711 }
712 EXPORT_SYMBOL_GPL(usbnet_set_settings);
713
usbnet_get_link(struct net_device * net)714 u32 usbnet_get_link (struct net_device *net)
715 {
716 struct usbnet *dev = netdev_priv(net);
717
718 /* If a check_connect is defined, return its result */
719 if (dev->driver_info->check_connect)
720 return dev->driver_info->check_connect (dev) == 0;
721
722 /* if the device has mii operations, use those */
723 if (dev->mii.mdio_read)
724 return mii_link_ok(&dev->mii);
725
726 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
727 return ethtool_op_get_link(net);
728 }
729 EXPORT_SYMBOL_GPL(usbnet_get_link);
730
usbnet_nway_reset(struct net_device * net)731 int usbnet_nway_reset(struct net_device *net)
732 {
733 struct usbnet *dev = netdev_priv(net);
734
735 if (!dev->mii.mdio_write)
736 return -EOPNOTSUPP;
737
738 return mii_nway_restart(&dev->mii);
739 }
740 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
741
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)742 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
743 {
744 struct usbnet *dev = netdev_priv(net);
745
746 strncpy (info->driver, dev->driver_name, sizeof info->driver);
747 strncpy (info->version, DRIVER_VERSION, sizeof info->version);
748 strncpy (info->fw_version, dev->driver_info->description,
749 sizeof info->fw_version);
750 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
751 }
752 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
753
usbnet_get_msglevel(struct net_device * net)754 u32 usbnet_get_msglevel (struct net_device *net)
755 {
756 struct usbnet *dev = netdev_priv(net);
757
758 return dev->msg_enable;
759 }
760 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
761
usbnet_set_msglevel(struct net_device * net,u32 level)762 void usbnet_set_msglevel (struct net_device *net, u32 level)
763 {
764 struct usbnet *dev = netdev_priv(net);
765
766 dev->msg_enable = level;
767 }
768 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
769
770 /* drivers may override default ethtool_ops in their bind() routine */
771 static struct ethtool_ops usbnet_ethtool_ops = {
772 .get_settings = usbnet_get_settings,
773 .set_settings = usbnet_set_settings,
774 .get_link = usbnet_get_link,
775 .nway_reset = usbnet_nway_reset,
776 .get_drvinfo = usbnet_get_drvinfo,
777 .get_msglevel = usbnet_get_msglevel,
778 .set_msglevel = usbnet_set_msglevel,
779 };
780
781 /*-------------------------------------------------------------------------*/
782
783 /* work that cannot be done in interrupt context uses keventd.
784 *
785 * NOTE: with 2.5 we could do more of this using completion callbacks,
786 * especially now that control transfers can be queued.
787 */
788 static void
kevent(struct work_struct * work)789 kevent (struct work_struct *work)
790 {
791 struct usbnet *dev =
792 container_of(work, struct usbnet, kevent);
793 int status;
794
795 /* usb_clear_halt() needs a thread context */
796 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
797 unlink_urbs (dev, &dev->txq);
798 status = usb_clear_halt (dev->udev, dev->out);
799 if (status < 0
800 && status != -EPIPE
801 && status != -ESHUTDOWN) {
802 if (netif_msg_tx_err (dev))
803 deverr (dev, "can't clear tx halt, status %d",
804 status);
805 } else {
806 clear_bit (EVENT_TX_HALT, &dev->flags);
807 if (status != -ESHUTDOWN)
808 netif_wake_queue (dev->net);
809 }
810 }
811 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
812 unlink_urbs (dev, &dev->rxq);
813 status = usb_clear_halt (dev->udev, dev->in);
814 if (status < 0
815 && status != -EPIPE
816 && status != -ESHUTDOWN) {
817 if (netif_msg_rx_err (dev))
818 deverr (dev, "can't clear rx halt, status %d",
819 status);
820 } else {
821 clear_bit (EVENT_RX_HALT, &dev->flags);
822 tasklet_schedule (&dev->bh);
823 }
824 }
825
826 /* tasklet could resubmit itself forever if memory is tight */
827 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
828 struct urb *urb = NULL;
829
830 if (netif_running (dev->net))
831 urb = usb_alloc_urb (0, GFP_KERNEL);
832 else
833 clear_bit (EVENT_RX_MEMORY, &dev->flags);
834 if (urb != NULL) {
835 clear_bit (EVENT_RX_MEMORY, &dev->flags);
836 rx_submit (dev, urb, GFP_KERNEL);
837 tasklet_schedule (&dev->bh);
838 }
839 }
840
841 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
842 struct driver_info *info = dev->driver_info;
843 int retval = 0;
844
845 clear_bit (EVENT_LINK_RESET, &dev->flags);
846 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
847 devinfo(dev, "link reset failed (%d) usbnet usb-%s-%s, %s",
848 retval,
849 dev->udev->bus->bus_name, dev->udev->devpath,
850 info->description);
851 }
852 }
853
854 if (dev->flags)
855 devdbg (dev, "kevent done, flags = 0x%lx",
856 dev->flags);
857 }
858
859 /*-------------------------------------------------------------------------*/
860
tx_complete(struct urb * urb)861 static void tx_complete (struct urb *urb)
862 {
863 struct sk_buff *skb = (struct sk_buff *) urb->context;
864 struct skb_data *entry = (struct skb_data *) skb->cb;
865 struct usbnet *dev = entry->dev;
866
867 if (urb->status == 0) {
868 dev->stats.tx_packets++;
869 dev->stats.tx_bytes += entry->length;
870 } else {
871 dev->stats.tx_errors++;
872
873 switch (urb->status) {
874 case -EPIPE:
875 usbnet_defer_kevent (dev, EVENT_TX_HALT);
876 break;
877
878 /* software-driven interface shutdown */
879 case -ECONNRESET: // async unlink
880 case -ESHUTDOWN: // hardware gone
881 break;
882
883 // like rx, tx gets controller i/o faults during khubd delays
884 // and so it uses the same throttling mechanism.
885 case -EPROTO:
886 case -ETIME:
887 case -EILSEQ:
888 if (!timer_pending (&dev->delay)) {
889 mod_timer (&dev->delay,
890 jiffies + THROTTLE_JIFFIES);
891 if (netif_msg_link (dev))
892 devdbg (dev, "tx throttle %d",
893 urb->status);
894 }
895 netif_stop_queue (dev->net);
896 break;
897 default:
898 if (netif_msg_tx_err (dev))
899 devdbg (dev, "tx err %d", entry->urb->status);
900 break;
901 }
902 }
903
904 urb->dev = NULL;
905 entry->state = tx_done;
906 defer_bh(dev, skb, &dev->txq);
907 }
908
909 /*-------------------------------------------------------------------------*/
910
usbnet_tx_timeout(struct net_device * net)911 static void usbnet_tx_timeout (struct net_device *net)
912 {
913 struct usbnet *dev = netdev_priv(net);
914
915 unlink_urbs (dev, &dev->txq);
916 tasklet_schedule (&dev->bh);
917
918 // FIXME: device recovery -- reset?
919 }
920
921 /*-------------------------------------------------------------------------*/
922
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)923 static int usbnet_start_xmit (struct sk_buff *skb, struct net_device *net)
924 {
925 struct usbnet *dev = netdev_priv(net);
926 int length;
927 int retval = NET_XMIT_SUCCESS;
928 struct urb *urb = NULL;
929 struct skb_data *entry;
930 struct driver_info *info = dev->driver_info;
931 unsigned long flags;
932
933 // some devices want funky USB-level framing, for
934 // win32 driver (usually) and/or hardware quirks
935 if (info->tx_fixup) {
936 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
937 if (!skb) {
938 if (netif_msg_tx_err (dev))
939 devdbg (dev, "can't tx_fixup skb");
940 goto drop;
941 }
942 }
943 length = skb->len;
944
945 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
946 if (netif_msg_tx_err (dev))
947 devdbg (dev, "no urb");
948 goto drop;
949 }
950
951 entry = (struct skb_data *) skb->cb;
952 entry->urb = urb;
953 entry->dev = dev;
954 entry->state = tx_start;
955 entry->length = length;
956
957 usb_fill_bulk_urb (urb, dev->udev, dev->out,
958 skb->data, skb->len, tx_complete, skb);
959
960 /* don't assume the hardware handles USB_ZERO_PACKET
961 * NOTE: strictly conforming cdc-ether devices should expect
962 * the ZLP here, but ignore the one-byte packet.
963 */
964 if ((length % dev->maxpacket) == 0) {
965 urb->transfer_buffer_length++;
966 if (skb_tailroom(skb)) {
967 skb->data[skb->len] = 0;
968 __skb_put(skb, 1);
969 }
970 }
971
972 spin_lock_irqsave (&dev->txq.lock, flags);
973
974 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
975 case -EPIPE:
976 netif_stop_queue (net);
977 usbnet_defer_kevent (dev, EVENT_TX_HALT);
978 break;
979 default:
980 if (netif_msg_tx_err (dev))
981 devdbg (dev, "tx: submit urb err %d", retval);
982 break;
983 case 0:
984 net->trans_start = jiffies;
985 __skb_queue_tail (&dev->txq, skb);
986 if (dev->txq.qlen >= TX_QLEN (dev))
987 netif_stop_queue (net);
988 }
989 spin_unlock_irqrestore (&dev->txq.lock, flags);
990
991 if (retval) {
992 if (netif_msg_tx_err (dev))
993 devdbg (dev, "drop, code %d", retval);
994 drop:
995 retval = NET_XMIT_SUCCESS;
996 dev->stats.tx_dropped++;
997 if (skb)
998 dev_kfree_skb_any (skb);
999 usb_free_urb (urb);
1000 } else if (netif_msg_tx_queued (dev)) {
1001 devdbg (dev, "> tx, len %d, type 0x%x",
1002 length, skb->protocol);
1003 }
1004 return retval;
1005 }
1006
1007
1008 /*-------------------------------------------------------------------------*/
1009
1010 // tasklet (work deferred from completions, in_irq) or timer
1011
usbnet_bh(unsigned long param)1012 static void usbnet_bh (unsigned long param)
1013 {
1014 struct usbnet *dev = (struct usbnet *) param;
1015 struct sk_buff *skb;
1016 struct skb_data *entry;
1017
1018 while ((skb = skb_dequeue (&dev->done))) {
1019 entry = (struct skb_data *) skb->cb;
1020 switch (entry->state) {
1021 case rx_done:
1022 entry->state = rx_cleanup;
1023 rx_process (dev, skb);
1024 continue;
1025 case tx_done:
1026 case rx_cleanup:
1027 usb_free_urb (entry->urb);
1028 dev_kfree_skb (skb);
1029 continue;
1030 default:
1031 devdbg (dev, "bogus skb state %d", entry->state);
1032 }
1033 }
1034
1035 // waiting for all pending urbs to complete?
1036 if (dev->wait) {
1037 if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1038 wake_up (dev->wait);
1039 }
1040
1041 // or are we maybe short a few urbs?
1042 } else if (netif_running (dev->net)
1043 && netif_device_present (dev->net)
1044 && !timer_pending (&dev->delay)
1045 && !test_bit (EVENT_RX_HALT, &dev->flags)) {
1046 int temp = dev->rxq.qlen;
1047 int qlen = RX_QLEN (dev);
1048
1049 if (temp < qlen) {
1050 struct urb *urb;
1051 int i;
1052
1053 // don't refill the queue all at once
1054 for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1055 urb = usb_alloc_urb (0, GFP_ATOMIC);
1056 if (urb != NULL)
1057 rx_submit (dev, urb, GFP_ATOMIC);
1058 }
1059 if (temp != dev->rxq.qlen && netif_msg_link (dev))
1060 devdbg (dev, "rxqlen %d --> %d",
1061 temp, dev->rxq.qlen);
1062 if (dev->rxq.qlen < qlen)
1063 tasklet_schedule (&dev->bh);
1064 }
1065 if (dev->txq.qlen < TX_QLEN (dev))
1066 netif_wake_queue (dev->net);
1067 }
1068 }
1069
1070
1071
1072 /*-------------------------------------------------------------------------
1073 *
1074 * USB Device Driver support
1075 *
1076 *-------------------------------------------------------------------------*/
1077
1078 // precondition: never called in_interrupt
1079
usbnet_disconnect(struct usb_interface * intf)1080 void usbnet_disconnect (struct usb_interface *intf)
1081 {
1082 struct usbnet *dev;
1083 struct usb_device *xdev;
1084 struct net_device *net;
1085
1086 dev = usb_get_intfdata(intf);
1087 usb_set_intfdata(intf, NULL);
1088 if (!dev)
1089 return;
1090
1091 xdev = interface_to_usbdev (intf);
1092
1093 if (netif_msg_probe (dev))
1094 devinfo (dev, "unregister '%s' usb-%s-%s, %s",
1095 intf->dev.driver->name,
1096 xdev->bus->bus_name, xdev->devpath,
1097 dev->driver_info->description);
1098
1099 net = dev->net;
1100 unregister_netdev (net);
1101
1102 /* we don't hold rtnl here ... */
1103 flush_scheduled_work ();
1104
1105 if (dev->driver_info->unbind)
1106 dev->driver_info->unbind (dev, intf);
1107
1108 free_netdev(net);
1109 usb_put_dev (xdev);
1110 }
1111 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1112
1113
1114 /*-------------------------------------------------------------------------*/
1115
1116 // precondition: never called in_interrupt
1117
1118 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1119 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1120 {
1121 struct usbnet *dev;
1122 struct net_device *net;
1123 struct usb_host_interface *interface;
1124 struct driver_info *info;
1125 struct usb_device *xdev;
1126 int status;
1127 const char *name;
1128
1129 name = udev->dev.driver->name;
1130 info = (struct driver_info *) prod->driver_info;
1131 if (!info) {
1132 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1133 return -ENODEV;
1134 }
1135 xdev = interface_to_usbdev (udev);
1136 interface = udev->cur_altsetting;
1137
1138 usb_get_dev (xdev);
1139
1140 status = -ENOMEM;
1141
1142 // set up our own records
1143 net = alloc_etherdev(sizeof(*dev));
1144 if (!net) {
1145 dbg ("can't kmalloc dev");
1146 goto out;
1147 }
1148
1149 dev = netdev_priv(net);
1150 dev->udev = xdev;
1151 dev->intf = udev;
1152 dev->driver_info = info;
1153 dev->driver_name = name;
1154 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1155 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1156 skb_queue_head_init (&dev->rxq);
1157 skb_queue_head_init (&dev->txq);
1158 skb_queue_head_init (&dev->done);
1159 dev->bh.func = usbnet_bh;
1160 dev->bh.data = (unsigned long) dev;
1161 INIT_WORK (&dev->kevent, kevent);
1162 dev->delay.function = usbnet_bh;
1163 dev->delay.data = (unsigned long) dev;
1164 init_timer (&dev->delay);
1165 mutex_init (&dev->phy_mutex);
1166
1167 dev->net = net;
1168 strcpy (net->name, "usb%d");
1169 memcpy (net->dev_addr, node_id, sizeof node_id);
1170
1171 /* rx and tx sides can use different message sizes;
1172 * bind() should set rx_urb_size in that case.
1173 */
1174 dev->hard_mtu = net->mtu + net->hard_header_len;
1175 #if 0
1176 // dma_supported() is deeply broken on almost all architectures
1177 // possible with some EHCI controllers
1178 if (dma_supported (&udev->dev, DMA_64BIT_MASK))
1179 net->features |= NETIF_F_HIGHDMA;
1180 #endif
1181
1182 net->change_mtu = usbnet_change_mtu;
1183 net->get_stats = usbnet_get_stats;
1184 net->hard_start_xmit = usbnet_start_xmit;
1185 net->open = usbnet_open;
1186 net->stop = usbnet_stop;
1187 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1188 net->tx_timeout = usbnet_tx_timeout;
1189 net->ethtool_ops = &usbnet_ethtool_ops;
1190
1191 // allow device-specific bind/init procedures
1192 // NOTE net->name still not usable ...
1193 if (info->bind) {
1194 status = info->bind (dev, udev);
1195 if (status < 0)
1196 goto out1;
1197
1198 // heuristic: "usb%d" for links we know are two-host,
1199 // else "eth%d" when there's reasonable doubt. userspace
1200 // can rename the link if it knows better.
1201 if ((dev->driver_info->flags & FLAG_ETHER) != 0
1202 && (net->dev_addr [0] & 0x02) == 0)
1203 strcpy (net->name, "eth%d");
1204 /* WLAN devices should always be named "wlan%d" */
1205 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1206 strcpy(net->name, "wlan%d");
1207
1208 /* maybe the remote can't receive an Ethernet MTU */
1209 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1210 net->mtu = dev->hard_mtu - net->hard_header_len;
1211 } else if (!info->in || !info->out)
1212 status = usbnet_get_endpoints (dev, udev);
1213 else {
1214 dev->in = usb_rcvbulkpipe (xdev, info->in);
1215 dev->out = usb_sndbulkpipe (xdev, info->out);
1216 if (!(info->flags & FLAG_NO_SETINT))
1217 status = usb_set_interface (xdev,
1218 interface->desc.bInterfaceNumber,
1219 interface->desc.bAlternateSetting);
1220 else
1221 status = 0;
1222
1223 }
1224 if (status >= 0 && dev->status)
1225 status = init_status (dev, udev);
1226 if (status < 0)
1227 goto out3;
1228
1229 if (!dev->rx_urb_size)
1230 dev->rx_urb_size = dev->hard_mtu;
1231 dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1232
1233 SET_NETDEV_DEV(net, &udev->dev);
1234 status = register_netdev (net);
1235 if (status)
1236 goto out3;
1237 if (netif_msg_probe (dev))
1238 devinfo (dev, "register '%s' at usb-%s-%s, %s, %pM",
1239 udev->dev.driver->name,
1240 xdev->bus->bus_name, xdev->devpath,
1241 dev->driver_info->description,
1242 net->dev_addr);
1243
1244 // ok, it's ready to go.
1245 usb_set_intfdata (udev, dev);
1246
1247 // start as if the link is up
1248 netif_device_attach (net);
1249
1250 return 0;
1251
1252 out3:
1253 if (info->unbind)
1254 info->unbind (dev, udev);
1255 out1:
1256 free_netdev(net);
1257 out:
1258 usb_put_dev(xdev);
1259 return status;
1260 }
1261 EXPORT_SYMBOL_GPL(usbnet_probe);
1262
1263 /*-------------------------------------------------------------------------*/
1264
1265 /*
1266 * suspend the whole driver as soon as the first interface is suspended
1267 * resume only when the last interface is resumed
1268 */
1269
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1270 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1271 {
1272 struct usbnet *dev = usb_get_intfdata(intf);
1273
1274 if (!dev->suspend_count++) {
1275 /*
1276 * accelerate emptying of the rx and queues, to avoid
1277 * having everything error out.
1278 */
1279 netif_device_detach (dev->net);
1280 (void) unlink_urbs (dev, &dev->rxq);
1281 (void) unlink_urbs (dev, &dev->txq);
1282 /*
1283 * reattach so runtime management can use and
1284 * wake the device
1285 */
1286 netif_device_attach (dev->net);
1287 }
1288 return 0;
1289 }
1290 EXPORT_SYMBOL_GPL(usbnet_suspend);
1291
usbnet_resume(struct usb_interface * intf)1292 int usbnet_resume (struct usb_interface *intf)
1293 {
1294 struct usbnet *dev = usb_get_intfdata(intf);
1295
1296 if (!--dev->suspend_count)
1297 tasklet_schedule (&dev->bh);
1298
1299 return 0;
1300 }
1301 EXPORT_SYMBOL_GPL(usbnet_resume);
1302
1303
1304 /*-------------------------------------------------------------------------*/
1305
usbnet_init(void)1306 static int __init usbnet_init(void)
1307 {
1308 /* compiler should optimize this out */
1309 BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb)
1310 < sizeof (struct skb_data));
1311
1312 random_ether_addr(node_id);
1313 return 0;
1314 }
1315 module_init(usbnet_init);
1316
usbnet_exit(void)1317 static void __exit usbnet_exit(void)
1318 {
1319 }
1320 module_exit(usbnet_exit);
1321
1322 MODULE_AUTHOR("David Brownell");
1323 MODULE_DESCRIPTION("USB network driver framework");
1324 MODULE_LICENSE("GPL");
1325