1 /*
2 * USB Network driver infrastructure
3 * Copyright (C) 2000-2005 by David Brownell
4 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 /*
21 * This is a generic "USB networking" framework that works with several
22 * kinds of full and high speed networking devices: host-to-host cables,
23 * smart usb peripherals, and actual Ethernet adapters.
24 *
25 * These devices usually differ in terms of control protocols (if they
26 * even have one!) and sometimes they define new framing to wrap or batch
27 * Ethernet packets. Otherwise, they talk to USB pretty much the same,
28 * so interface (un)binding, endpoint I/O queues, fault handling, and other
29 * issues can usefully be addressed by this framework.
30 */
31
32 // #define DEBUG // error path messages, extra info
33 // #define VERBOSE // more; success messages
34
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/netdevice.h>
38 #include <linux/etherdevice.h>
39 #include <linux/ctype.h>
40 #include <linux/ethtool.h>
41 #include <linux/workqueue.h>
42 #include <linux/mii.h>
43 #include <linux/usb.h>
44 #include <linux/usb/usbnet.h>
45 #include <linux/slab.h>
46 #include <linux/kernel.h>
47 #include <linux/pm_runtime.h>
48
49 #define DRIVER_VERSION "22-Aug-2005"
50
51
52 /*-------------------------------------------------------------------------*/
53
54 /*
55 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
56 * Several dozen bytes of IPv4 data can fit in two such transactions.
57 * One maximum size Ethernet packet takes twenty four of them.
58 * For high speed, each frame comfortably fits almost 36 max size
59 * Ethernet packets (so queues should be bigger).
60 *
61 * The goal is to let the USB host controller be busy for 5msec or
62 * more before an irq is required, under load. Jumbograms change
63 * the equation.
64 */
65 #define MAX_QUEUE_MEMORY (60 * 1518)
66 #define RX_QLEN(dev) ((dev)->rx_qlen)
67 #define TX_QLEN(dev) ((dev)->tx_qlen)
68
69 // reawaken network queue this soon after stopping; else watchdog barks
70 #define TX_TIMEOUT_JIFFIES (5*HZ)
71
72 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
73 * us (it polls at HZ/4 usually) before we report too many false errors.
74 */
75 #define THROTTLE_JIFFIES (HZ/8)
76
77 // between wakeups
78 #define UNLINK_TIMEOUT_MS 3
79
80 /*-------------------------------------------------------------------------*/
81
82 // randomly generated ethernet address
83 static u8 node_id [ETH_ALEN];
84
85 /* 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 altsettings.
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
116 /* ignore endpoints which cannot transfer data */
117 if (!usb_endpoint_maxp(&e->desc))
118 continue;
119
120 switch (e->desc.bmAttributes) {
121 case USB_ENDPOINT_XFER_INT:
122 if (!usb_endpoint_dir_in(&e->desc))
123 continue;
124 intr = 1;
125 /* FALLTHROUGH */
126 case USB_ENDPOINT_XFER_BULK:
127 break;
128 default:
129 continue;
130 }
131 if (usb_endpoint_dir_in(&e->desc)) {
132 if (!intr && !in)
133 in = e;
134 else if (intr && !status)
135 status = e;
136 } else {
137 if (!out)
138 out = e;
139 }
140 }
141 if (in && out)
142 break;
143 }
144 if (!alt || !in || !out)
145 return -EINVAL;
146
147 if (alt->desc.bAlternateSetting != 0 ||
148 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
149 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
150 alt->desc.bAlternateSetting);
151 if (tmp < 0)
152 return tmp;
153 }
154
155 dev->in = usb_rcvbulkpipe (dev->udev,
156 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
157 dev->out = usb_sndbulkpipe (dev->udev,
158 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
159 dev->status = status;
160 return 0;
161 }
162 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
163
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)164 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
165 {
166 int tmp = -1, ret;
167 unsigned char buf [13];
168
169 ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
170 if (ret == 12)
171 tmp = hex2bin(dev->net->dev_addr, buf, 6);
172 if (tmp < 0) {
173 dev_dbg(&dev->udev->dev,
174 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
175 if (ret >= 0)
176 ret = -EINVAL;
177 return ret;
178 }
179 return 0;
180 }
181 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
182
intr_complete(struct urb * urb)183 static void intr_complete (struct urb *urb)
184 {
185 struct usbnet *dev = urb->context;
186 int status = urb->status;
187
188 switch (status) {
189 /* success */
190 case 0:
191 dev->driver_info->status(dev, urb);
192 break;
193
194 /* software-driven interface shutdown */
195 case -ENOENT: /* urb killed */
196 case -ESHUTDOWN: /* hardware gone */
197 netif_dbg(dev, ifdown, dev->net,
198 "intr shutdown, code %d\n", status);
199 return;
200
201 /* NOTE: not throttling like RX/TX, since this endpoint
202 * already polls infrequently
203 */
204 default:
205 netdev_dbg(dev->net, "intr status %d\n", status);
206 break;
207 }
208
209 status = usb_submit_urb (urb, GFP_ATOMIC);
210 if (status != 0)
211 netif_err(dev, timer, dev->net,
212 "intr resubmit --> %d\n", status);
213 }
214
init_status(struct usbnet * dev,struct usb_interface * intf)215 static int init_status (struct usbnet *dev, struct usb_interface *intf)
216 {
217 char *buf = NULL;
218 unsigned pipe = 0;
219 unsigned maxp;
220 unsigned period;
221
222 if (!dev->driver_info->status)
223 return 0;
224
225 pipe = usb_rcvintpipe (dev->udev,
226 dev->status->desc.bEndpointAddress
227 & USB_ENDPOINT_NUMBER_MASK);
228 maxp = usb_maxpacket (dev->udev, pipe, 0);
229
230 /* avoid 1 msec chatter: min 8 msec poll rate */
231 period = max ((int) dev->status->desc.bInterval,
232 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
233
234 buf = kmalloc (maxp, GFP_KERNEL);
235 if (buf) {
236 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
237 if (!dev->interrupt) {
238 kfree (buf);
239 return -ENOMEM;
240 } else {
241 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
242 buf, maxp, intr_complete, dev, period);
243 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
244 dev_dbg(&intf->dev,
245 "status ep%din, %d bytes period %d\n",
246 usb_pipeendpoint(pipe), maxp, period);
247 }
248 }
249 return 0;
250 }
251
252 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)253 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
254 {
255 int ret = 0;
256
257 WARN_ON_ONCE(dev->interrupt == NULL);
258 if (dev->interrupt) {
259 mutex_lock(&dev->interrupt_mutex);
260
261 if (++dev->interrupt_count == 1)
262 ret = usb_submit_urb(dev->interrupt, mem_flags);
263
264 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
265 dev->interrupt_count);
266 mutex_unlock(&dev->interrupt_mutex);
267 }
268 return ret;
269 }
270 EXPORT_SYMBOL_GPL(usbnet_status_start);
271
272 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)273 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
274 {
275 int ret = 0;
276
277 mutex_lock(&dev->interrupt_mutex);
278 if (dev->interrupt_count) {
279 ret = usb_submit_urb(dev->interrupt, mem_flags);
280 dev_dbg(&dev->udev->dev,
281 "submitted interrupt URB for resume\n");
282 }
283 mutex_unlock(&dev->interrupt_mutex);
284 return ret;
285 }
286
287 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)288 void usbnet_status_stop(struct usbnet *dev)
289 {
290 if (dev->interrupt) {
291 mutex_lock(&dev->interrupt_mutex);
292 WARN_ON(dev->interrupt_count == 0);
293
294 if (dev->interrupt_count && --dev->interrupt_count == 0)
295 usb_kill_urb(dev->interrupt);
296
297 dev_dbg(&dev->udev->dev,
298 "decremented interrupt URB count to %d\n",
299 dev->interrupt_count);
300 mutex_unlock(&dev->interrupt_mutex);
301 }
302 }
303 EXPORT_SYMBOL_GPL(usbnet_status_stop);
304
305 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)306 static void __usbnet_status_stop_force(struct usbnet *dev)
307 {
308 if (dev->interrupt) {
309 mutex_lock(&dev->interrupt_mutex);
310 usb_kill_urb(dev->interrupt);
311 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
312 mutex_unlock(&dev->interrupt_mutex);
313 }
314 }
315
316 /* Passes this packet up the stack, updating its accounting.
317 * Some link protocols batch packets, so their rx_fixup paths
318 * can return clones as well as just modify the original skb.
319 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)320 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
321 {
322 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->stats64);
323 unsigned long flags;
324 int status;
325
326 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
327 skb_queue_tail(&dev->rxq_pause, skb);
328 return;
329 }
330
331 /* only update if unset to allow minidriver rx_fixup override */
332 if (skb->protocol == 0)
333 skb->protocol = eth_type_trans (skb, dev->net);
334
335 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
336 stats64->rx_packets++;
337 stats64->rx_bytes += skb->len;
338 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
339
340 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
341 skb->len + sizeof (struct ethhdr), skb->protocol);
342 memset (skb->cb, 0, sizeof (struct skb_data));
343
344 if (skb_defer_rx_timestamp(skb))
345 return;
346
347 status = netif_rx (skb);
348 if (status != NET_RX_SUCCESS)
349 netif_dbg(dev, rx_err, dev->net,
350 "netif_rx status %d\n", status);
351 }
352 EXPORT_SYMBOL_GPL(usbnet_skb_return);
353
354 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)355 void usbnet_update_max_qlen(struct usbnet *dev)
356 {
357 enum usb_device_speed speed = dev->udev->speed;
358
359 if (!dev->rx_urb_size || !dev->hard_mtu)
360 goto insanity;
361 switch (speed) {
362 case USB_SPEED_HIGH:
363 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
364 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
365 break;
366 case USB_SPEED_SUPER:
367 case USB_SPEED_SUPER_PLUS:
368 /*
369 * Not take default 5ms qlen for super speed HC to
370 * save memory, and iperf tests show 2.5ms qlen can
371 * work well
372 */
373 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
374 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
375 break;
376 default:
377 insanity:
378 dev->rx_qlen = dev->tx_qlen = 4;
379 }
380 }
381 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
382
383
384 /*-------------------------------------------------------------------------
385 *
386 * Network Device Driver (peer link to "Host Device", from USB host)
387 *
388 *-------------------------------------------------------------------------*/
389
usbnet_change_mtu(struct net_device * net,int new_mtu)390 int usbnet_change_mtu (struct net_device *net, int new_mtu)
391 {
392 struct usbnet *dev = netdev_priv(net);
393 int ll_mtu = new_mtu + net->hard_header_len;
394 int old_hard_mtu = dev->hard_mtu;
395 int old_rx_urb_size = dev->rx_urb_size;
396
397 // no second zero-length packet read wanted after mtu-sized packets
398 if ((ll_mtu % dev->maxpacket) == 0)
399 return -EDOM;
400 net->mtu = new_mtu;
401
402 dev->hard_mtu = net->mtu + net->hard_header_len;
403 if (dev->rx_urb_size == old_hard_mtu) {
404 dev->rx_urb_size = dev->hard_mtu;
405 if (dev->rx_urb_size > old_rx_urb_size) {
406 usbnet_pause_rx(dev);
407 usbnet_unlink_rx_urbs(dev);
408 usbnet_resume_rx(dev);
409 }
410 }
411
412 /* max qlen depend on hard_mtu and rx_urb_size */
413 usbnet_update_max_qlen(dev);
414
415 return 0;
416 }
417 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
418
419 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)420 static void __usbnet_queue_skb(struct sk_buff_head *list,
421 struct sk_buff *newsk, enum skb_state state)
422 {
423 struct skb_data *entry = (struct skb_data *) newsk->cb;
424
425 __skb_queue_tail(list, newsk);
426 entry->state = state;
427 }
428
429 /*-------------------------------------------------------------------------*/
430
431 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
432 * completion callbacks. 2.5 should have fixed those bugs...
433 */
434
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)435 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
436 struct sk_buff_head *list, enum skb_state state)
437 {
438 unsigned long flags;
439 enum skb_state old_state;
440 struct skb_data *entry = (struct skb_data *) skb->cb;
441
442 spin_lock_irqsave(&list->lock, flags);
443 old_state = entry->state;
444 entry->state = state;
445 __skb_unlink(skb, list);
446
447 /* defer_bh() is never called with list == &dev->done.
448 * spin_lock_nested() tells lockdep that it is OK to take
449 * dev->done.lock here with list->lock held.
450 */
451 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
452
453 __skb_queue_tail(&dev->done, skb);
454 if (dev->done.qlen == 1)
455 tasklet_schedule(&dev->bh);
456 spin_unlock(&dev->done.lock);
457 spin_unlock_irqrestore(&list->lock, flags);
458 return old_state;
459 }
460
461 /* some work can't be done in tasklets, so we use keventd
462 *
463 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
464 * but tasklet_schedule() doesn't. hope the failure is rare.
465 */
usbnet_defer_kevent(struct usbnet * dev,int work)466 void usbnet_defer_kevent (struct usbnet *dev, int work)
467 {
468 set_bit (work, &dev->flags);
469 if (!schedule_work (&dev->kevent)) {
470 if (net_ratelimit())
471 netdev_err(dev->net, "kevent %d may have been dropped\n", work);
472 } else {
473 netdev_dbg(dev->net, "kevent %d scheduled\n", work);
474 }
475 }
476 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
477
478 /*-------------------------------------------------------------------------*/
479
480 static void rx_complete (struct urb *urb);
481
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)482 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
483 {
484 struct sk_buff *skb;
485 struct skb_data *entry;
486 int retval = 0;
487 unsigned long lockflags;
488 size_t size = dev->rx_urb_size;
489
490 /* prevent rx skb allocation when error ratio is high */
491 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
492 usb_free_urb(urb);
493 return -ENOLINK;
494 }
495
496 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
497 skb = __netdev_alloc_skb(dev->net, size, flags);
498 else
499 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
500 if (!skb) {
501 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
502 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
503 usb_free_urb (urb);
504 return -ENOMEM;
505 }
506
507 entry = (struct skb_data *) skb->cb;
508 entry->urb = urb;
509 entry->dev = dev;
510 entry->length = 0;
511
512 usb_fill_bulk_urb (urb, dev->udev, dev->in,
513 skb->data, size, rx_complete, skb);
514
515 spin_lock_irqsave (&dev->rxq.lock, lockflags);
516
517 if (netif_running (dev->net) &&
518 netif_device_present (dev->net) &&
519 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
520 !test_bit (EVENT_RX_HALT, &dev->flags) &&
521 !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
522 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
523 case -EPIPE:
524 usbnet_defer_kevent (dev, EVENT_RX_HALT);
525 break;
526 case -ENOMEM:
527 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
528 break;
529 case -ENODEV:
530 netif_dbg(dev, ifdown, dev->net, "device gone\n");
531 netif_device_detach (dev->net);
532 break;
533 case -EHOSTUNREACH:
534 retval = -ENOLINK;
535 break;
536 default:
537 netif_dbg(dev, rx_err, dev->net,
538 "rx submit, %d\n", retval);
539 tasklet_schedule (&dev->bh);
540 break;
541 case 0:
542 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
543 }
544 } else {
545 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
546 retval = -ENOLINK;
547 }
548 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
549 if (retval) {
550 dev_kfree_skb_any (skb);
551 usb_free_urb (urb);
552 }
553 return retval;
554 }
555
556
557 /*-------------------------------------------------------------------------*/
558
rx_process(struct usbnet * dev,struct sk_buff * skb)559 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
560 {
561 if (dev->driver_info->rx_fixup &&
562 !dev->driver_info->rx_fixup (dev, skb)) {
563 /* With RX_ASSEMBLE, rx_fixup() must update counters */
564 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
565 dev->net->stats.rx_errors++;
566 goto done;
567 }
568 // else network stack removes extra byte if we forced a short packet
569
570 /* all data was already cloned from skb inside the driver */
571 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
572 goto done;
573
574 if (skb->len < ETH_HLEN) {
575 dev->net->stats.rx_errors++;
576 dev->net->stats.rx_length_errors++;
577 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
578 } else {
579 usbnet_skb_return(dev, skb);
580 return;
581 }
582
583 done:
584 skb_queue_tail(&dev->done, skb);
585 }
586
587 /*-------------------------------------------------------------------------*/
588
rx_complete(struct urb * urb)589 static void rx_complete (struct urb *urb)
590 {
591 struct sk_buff *skb = (struct sk_buff *) urb->context;
592 struct skb_data *entry = (struct skb_data *) skb->cb;
593 struct usbnet *dev = entry->dev;
594 int urb_status = urb->status;
595 enum skb_state state;
596
597 skb_put (skb, urb->actual_length);
598 state = rx_done;
599 entry->urb = NULL;
600
601 switch (urb_status) {
602 /* success */
603 case 0:
604 break;
605
606 /* stalls need manual reset. this is rare ... except that
607 * when going through USB 2.0 TTs, unplug appears this way.
608 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
609 * storm, recovering as needed.
610 */
611 case -EPIPE:
612 dev->net->stats.rx_errors++;
613 usbnet_defer_kevent (dev, EVENT_RX_HALT);
614 // FALLTHROUGH
615
616 /* software-driven interface shutdown */
617 case -ECONNRESET: /* async unlink */
618 case -ESHUTDOWN: /* hardware gone */
619 netif_dbg(dev, ifdown, dev->net,
620 "rx shutdown, code %d\n", urb_status);
621 goto block;
622
623 /* we get controller i/o faults during hub_wq disconnect() delays.
624 * throttle down resubmits, to avoid log floods; just temporarily,
625 * so we still recover when the fault isn't a hub_wq delay.
626 */
627 case -EPROTO:
628 case -ETIME:
629 case -EILSEQ:
630 dev->net->stats.rx_errors++;
631 if (!timer_pending (&dev->delay)) {
632 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
633 netif_dbg(dev, link, dev->net,
634 "rx throttle %d\n", urb_status);
635 }
636 block:
637 state = rx_cleanup;
638 entry->urb = urb;
639 urb = NULL;
640 break;
641
642 /* data overrun ... flush fifo? */
643 case -EOVERFLOW:
644 dev->net->stats.rx_over_errors++;
645 // FALLTHROUGH
646
647 default:
648 state = rx_cleanup;
649 dev->net->stats.rx_errors++;
650 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
651 break;
652 }
653
654 /* stop rx if packet error rate is high */
655 if (++dev->pkt_cnt > 30) {
656 dev->pkt_cnt = 0;
657 dev->pkt_err = 0;
658 } else {
659 if (state == rx_cleanup)
660 dev->pkt_err++;
661 if (dev->pkt_err > 20)
662 set_bit(EVENT_RX_KILL, &dev->flags);
663 }
664
665 state = defer_bh(dev, skb, &dev->rxq, state);
666
667 if (urb) {
668 if (netif_running (dev->net) &&
669 !test_bit (EVENT_RX_HALT, &dev->flags) &&
670 state != unlink_start) {
671 rx_submit (dev, urb, GFP_ATOMIC);
672 usb_mark_last_busy(dev->udev);
673 return;
674 }
675 usb_free_urb (urb);
676 }
677 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
678 }
679
680 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)681 void usbnet_pause_rx(struct usbnet *dev)
682 {
683 set_bit(EVENT_RX_PAUSED, &dev->flags);
684
685 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
686 }
687 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
688
usbnet_resume_rx(struct usbnet * dev)689 void usbnet_resume_rx(struct usbnet *dev)
690 {
691 struct sk_buff *skb;
692 int num = 0;
693
694 clear_bit(EVENT_RX_PAUSED, &dev->flags);
695
696 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
697 usbnet_skb_return(dev, skb);
698 num++;
699 }
700
701 tasklet_schedule(&dev->bh);
702
703 netif_dbg(dev, rx_status, dev->net,
704 "paused rx queue disabled, %d skbs requeued\n", num);
705 }
706 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
707
usbnet_purge_paused_rxq(struct usbnet * dev)708 void usbnet_purge_paused_rxq(struct usbnet *dev)
709 {
710 skb_queue_purge(&dev->rxq_pause);
711 }
712 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
713
714 /*-------------------------------------------------------------------------*/
715
716 // unlink pending rx/tx; completion handlers do all other cleanup
717
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)718 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
719 {
720 unsigned long flags;
721 struct sk_buff *skb;
722 int count = 0;
723
724 spin_lock_irqsave (&q->lock, flags);
725 while (!skb_queue_empty(q)) {
726 struct skb_data *entry;
727 struct urb *urb;
728 int retval;
729
730 skb_queue_walk(q, skb) {
731 entry = (struct skb_data *) skb->cb;
732 if (entry->state != unlink_start)
733 goto found;
734 }
735 break;
736 found:
737 entry->state = unlink_start;
738 urb = entry->urb;
739
740 /*
741 * Get reference count of the URB to avoid it to be
742 * freed during usb_unlink_urb, which may trigger
743 * use-after-free problem inside usb_unlink_urb since
744 * usb_unlink_urb is always racing with .complete
745 * handler(include defer_bh).
746 */
747 usb_get_urb(urb);
748 spin_unlock_irqrestore(&q->lock, flags);
749 // during some PM-driven resume scenarios,
750 // these (async) unlinks complete immediately
751 retval = usb_unlink_urb (urb);
752 if (retval != -EINPROGRESS && retval != 0)
753 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
754 else
755 count++;
756 usb_put_urb(urb);
757 spin_lock_irqsave(&q->lock, flags);
758 }
759 spin_unlock_irqrestore (&q->lock, flags);
760 return count;
761 }
762
763 // Flush all pending rx urbs
764 // minidrivers may need to do this when the MTU changes
765
usbnet_unlink_rx_urbs(struct usbnet * dev)766 void usbnet_unlink_rx_urbs(struct usbnet *dev)
767 {
768 if (netif_running(dev->net)) {
769 (void) unlink_urbs (dev, &dev->rxq);
770 tasklet_schedule(&dev->bh);
771 }
772 }
773 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
774
775 /*-------------------------------------------------------------------------*/
776
wait_skb_queue_empty(struct sk_buff_head * q)777 static void wait_skb_queue_empty(struct sk_buff_head *q)
778 {
779 unsigned long flags;
780
781 spin_lock_irqsave(&q->lock, flags);
782 while (!skb_queue_empty(q)) {
783 spin_unlock_irqrestore(&q->lock, flags);
784 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
785 set_current_state(TASK_UNINTERRUPTIBLE);
786 spin_lock_irqsave(&q->lock, flags);
787 }
788 spin_unlock_irqrestore(&q->lock, flags);
789 }
790
791 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)792 static void usbnet_terminate_urbs(struct usbnet *dev)
793 {
794 DECLARE_WAITQUEUE(wait, current);
795 int temp;
796
797 /* ensure there are no more active urbs */
798 add_wait_queue(&dev->wait, &wait);
799 set_current_state(TASK_UNINTERRUPTIBLE);
800 temp = unlink_urbs(dev, &dev->txq) +
801 unlink_urbs(dev, &dev->rxq);
802
803 /* maybe wait for deletions to finish. */
804 wait_skb_queue_empty(&dev->rxq);
805 wait_skb_queue_empty(&dev->txq);
806 wait_skb_queue_empty(&dev->done);
807 netif_dbg(dev, ifdown, dev->net,
808 "waited for %d urb completions\n", temp);
809 set_current_state(TASK_RUNNING);
810 remove_wait_queue(&dev->wait, &wait);
811 }
812
usbnet_stop(struct net_device * net)813 int usbnet_stop (struct net_device *net)
814 {
815 struct usbnet *dev = netdev_priv(net);
816 struct driver_info *info = dev->driver_info;
817 int retval, pm, mpn;
818
819 clear_bit(EVENT_DEV_OPEN, &dev->flags);
820 netif_stop_queue (net);
821
822 netif_info(dev, ifdown, dev->net,
823 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
824 net->stats.rx_packets, net->stats.tx_packets,
825 net->stats.rx_errors, net->stats.tx_errors);
826
827 /* to not race resume */
828 pm = usb_autopm_get_interface(dev->intf);
829 /* allow minidriver to stop correctly (wireless devices to turn off
830 * radio etc) */
831 if (info->stop) {
832 retval = info->stop(dev);
833 if (retval < 0)
834 netif_info(dev, ifdown, dev->net,
835 "stop fail (%d) usbnet usb-%s-%s, %s\n",
836 retval,
837 dev->udev->bus->bus_name, dev->udev->devpath,
838 info->description);
839 }
840
841 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
842 usbnet_terminate_urbs(dev);
843
844 usbnet_status_stop(dev);
845
846 usbnet_purge_paused_rxq(dev);
847
848 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
849
850 /* deferred work (task, timer, softirq) must also stop.
851 * can't flush_scheduled_work() until we drop rtnl (later),
852 * else workers could deadlock; so make workers a NOP.
853 */
854 dev->flags = 0;
855 del_timer_sync (&dev->delay);
856 tasklet_kill (&dev->bh);
857 if (!pm)
858 usb_autopm_put_interface(dev->intf);
859
860 if (info->manage_power && mpn)
861 info->manage_power(dev, 0);
862 else
863 usb_autopm_put_interface(dev->intf);
864
865 return 0;
866 }
867 EXPORT_SYMBOL_GPL(usbnet_stop);
868
869 /*-------------------------------------------------------------------------*/
870
871 // posts reads, and enables write queuing
872
873 // precondition: never called in_interrupt
874
usbnet_open(struct net_device * net)875 int usbnet_open (struct net_device *net)
876 {
877 struct usbnet *dev = netdev_priv(net);
878 int retval;
879 struct driver_info *info = dev->driver_info;
880
881 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
882 netif_info(dev, ifup, dev->net,
883 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
884 retval,
885 dev->udev->bus->bus_name,
886 dev->udev->devpath,
887 info->description);
888 goto done_nopm;
889 }
890
891 // put into "known safe" state
892 if (info->reset && (retval = info->reset (dev)) < 0) {
893 netif_info(dev, ifup, dev->net,
894 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
895 retval,
896 dev->udev->bus->bus_name,
897 dev->udev->devpath,
898 info->description);
899 goto done;
900 }
901
902 /* hard_mtu or rx_urb_size may change in reset() */
903 usbnet_update_max_qlen(dev);
904
905 // insist peer be connected
906 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
907 netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
908 goto done;
909 }
910
911 /* start any status interrupt transfer */
912 if (dev->interrupt) {
913 retval = usbnet_status_start(dev, GFP_KERNEL);
914 if (retval < 0) {
915 netif_err(dev, ifup, dev->net,
916 "intr submit %d\n", retval);
917 goto done;
918 }
919 }
920
921 set_bit(EVENT_DEV_OPEN, &dev->flags);
922 netif_start_queue (net);
923 netif_info(dev, ifup, dev->net,
924 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
925 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
926 dev->net->mtu,
927 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
928 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
929 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
930 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
931 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
932 "simple");
933
934 /* reset rx error state */
935 dev->pkt_cnt = 0;
936 dev->pkt_err = 0;
937 clear_bit(EVENT_RX_KILL, &dev->flags);
938
939 // delay posting reads until we're fully open
940 tasklet_schedule (&dev->bh);
941 if (info->manage_power) {
942 retval = info->manage_power(dev, 1);
943 if (retval < 0) {
944 retval = 0;
945 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
946 } else {
947 usb_autopm_put_interface(dev->intf);
948 }
949 }
950 return retval;
951 done:
952 usb_autopm_put_interface(dev->intf);
953 done_nopm:
954 return retval;
955 }
956 EXPORT_SYMBOL_GPL(usbnet_open);
957
958 /*-------------------------------------------------------------------------*/
959
960 /* ethtool methods; minidrivers may need to add some more, but
961 * they'll probably want to use this base set.
962 */
963
usbnet_get_link_ksettings(struct net_device * net,struct ethtool_link_ksettings * cmd)964 int usbnet_get_link_ksettings(struct net_device *net,
965 struct ethtool_link_ksettings *cmd)
966 {
967 struct usbnet *dev = netdev_priv(net);
968
969 if (!dev->mii.mdio_read)
970 return -EOPNOTSUPP;
971
972 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
973
974 return 0;
975 }
976 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings);
977
usbnet_set_link_ksettings(struct net_device * net,const struct ethtool_link_ksettings * cmd)978 int usbnet_set_link_ksettings(struct net_device *net,
979 const struct ethtool_link_ksettings *cmd)
980 {
981 struct usbnet *dev = netdev_priv(net);
982 int retval;
983
984 if (!dev->mii.mdio_write)
985 return -EOPNOTSUPP;
986
987 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
988
989 /* link speed/duplex might have changed */
990 if (dev->driver_info->link_reset)
991 dev->driver_info->link_reset(dev);
992
993 /* hard_mtu or rx_urb_size may change in link_reset() */
994 usbnet_update_max_qlen(dev);
995
996 return retval;
997 }
998 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings);
999
usbnet_get_stats64(struct net_device * net,struct rtnl_link_stats64 * stats)1000 void usbnet_get_stats64(struct net_device *net, struct rtnl_link_stats64 *stats)
1001 {
1002 struct usbnet *dev = netdev_priv(net);
1003 unsigned int start;
1004 int cpu;
1005
1006 netdev_stats_to_stats64(stats, &net->stats);
1007
1008 for_each_possible_cpu(cpu) {
1009 struct pcpu_sw_netstats *stats64;
1010 u64 rx_packets, rx_bytes;
1011 u64 tx_packets, tx_bytes;
1012
1013 stats64 = per_cpu_ptr(dev->stats64, cpu);
1014
1015 do {
1016 start = u64_stats_fetch_begin_irq(&stats64->syncp);
1017 rx_packets = stats64->rx_packets;
1018 rx_bytes = stats64->rx_bytes;
1019 tx_packets = stats64->tx_packets;
1020 tx_bytes = stats64->tx_bytes;
1021 } while (u64_stats_fetch_retry_irq(&stats64->syncp, start));
1022
1023 stats->rx_packets += rx_packets;
1024 stats->rx_bytes += rx_bytes;
1025 stats->tx_packets += tx_packets;
1026 stats->tx_bytes += tx_bytes;
1027 }
1028 }
1029 EXPORT_SYMBOL_GPL(usbnet_get_stats64);
1030
usbnet_get_link(struct net_device * net)1031 u32 usbnet_get_link (struct net_device *net)
1032 {
1033 struct usbnet *dev = netdev_priv(net);
1034
1035 /* If a check_connect is defined, return its result */
1036 if (dev->driver_info->check_connect)
1037 return dev->driver_info->check_connect (dev) == 0;
1038
1039 /* if the device has mii operations, use those */
1040 if (dev->mii.mdio_read)
1041 return mii_link_ok(&dev->mii);
1042
1043 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1044 return ethtool_op_get_link(net);
1045 }
1046 EXPORT_SYMBOL_GPL(usbnet_get_link);
1047
usbnet_nway_reset(struct net_device * net)1048 int usbnet_nway_reset(struct net_device *net)
1049 {
1050 struct usbnet *dev = netdev_priv(net);
1051
1052 if (!dev->mii.mdio_write)
1053 return -EOPNOTSUPP;
1054
1055 return mii_nway_restart(&dev->mii);
1056 }
1057 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1058
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1059 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1060 {
1061 struct usbnet *dev = netdev_priv(net);
1062
1063 strlcpy (info->driver, dev->driver_name, sizeof info->driver);
1064 strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
1065 strlcpy (info->fw_version, dev->driver_info->description,
1066 sizeof info->fw_version);
1067 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1068 }
1069 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1070
usbnet_get_msglevel(struct net_device * net)1071 u32 usbnet_get_msglevel (struct net_device *net)
1072 {
1073 struct usbnet *dev = netdev_priv(net);
1074
1075 return dev->msg_enable;
1076 }
1077 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1078
usbnet_set_msglevel(struct net_device * net,u32 level)1079 void usbnet_set_msglevel (struct net_device *net, u32 level)
1080 {
1081 struct usbnet *dev = netdev_priv(net);
1082
1083 dev->msg_enable = level;
1084 }
1085 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1086
1087 /* drivers may override default ethtool_ops in their bind() routine */
1088 static const struct ethtool_ops usbnet_ethtool_ops = {
1089 .get_link = usbnet_get_link,
1090 .nway_reset = usbnet_nway_reset,
1091 .get_drvinfo = usbnet_get_drvinfo,
1092 .get_msglevel = usbnet_get_msglevel,
1093 .set_msglevel = usbnet_set_msglevel,
1094 .get_ts_info = ethtool_op_get_ts_info,
1095 .get_link_ksettings = usbnet_get_link_ksettings,
1096 .set_link_ksettings = usbnet_set_link_ksettings,
1097 };
1098
1099 /*-------------------------------------------------------------------------*/
1100
__handle_link_change(struct usbnet * dev)1101 static void __handle_link_change(struct usbnet *dev)
1102 {
1103 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1104 return;
1105
1106 if (!netif_carrier_ok(dev->net)) {
1107 /* kill URBs for reading packets to save bus bandwidth */
1108 unlink_urbs(dev, &dev->rxq);
1109
1110 /*
1111 * tx_timeout will unlink URBs for sending packets and
1112 * tx queue is stopped by netcore after link becomes off
1113 */
1114 } else {
1115 /* submitting URBs for reading packets */
1116 tasklet_schedule(&dev->bh);
1117 }
1118
1119 /* hard_mtu or rx_urb_size may change during link change */
1120 usbnet_update_max_qlen(dev);
1121
1122 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1123 }
1124
usbnet_set_rx_mode(struct net_device * net)1125 static void usbnet_set_rx_mode(struct net_device *net)
1126 {
1127 struct usbnet *dev = netdev_priv(net);
1128
1129 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1130 }
1131
__handle_set_rx_mode(struct usbnet * dev)1132 static void __handle_set_rx_mode(struct usbnet *dev)
1133 {
1134 if (dev->driver_info->set_rx_mode)
1135 (dev->driver_info->set_rx_mode)(dev);
1136
1137 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1138 }
1139
1140 /* work that cannot be done in interrupt context uses keventd.
1141 *
1142 * NOTE: with 2.5 we could do more of this using completion callbacks,
1143 * especially now that control transfers can be queued.
1144 */
1145 static void
usbnet_deferred_kevent(struct work_struct * work)1146 usbnet_deferred_kevent (struct work_struct *work)
1147 {
1148 struct usbnet *dev =
1149 container_of(work, struct usbnet, kevent);
1150 int status;
1151
1152 /* usb_clear_halt() needs a thread context */
1153 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1154 unlink_urbs (dev, &dev->txq);
1155 status = usb_autopm_get_interface(dev->intf);
1156 if (status < 0)
1157 goto fail_pipe;
1158 status = usb_clear_halt (dev->udev, dev->out);
1159 usb_autopm_put_interface(dev->intf);
1160 if (status < 0 &&
1161 status != -EPIPE &&
1162 status != -ESHUTDOWN) {
1163 if (netif_msg_tx_err (dev))
1164 fail_pipe:
1165 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1166 status);
1167 } else {
1168 clear_bit (EVENT_TX_HALT, &dev->flags);
1169 if (status != -ESHUTDOWN)
1170 netif_wake_queue (dev->net);
1171 }
1172 }
1173 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1174 unlink_urbs (dev, &dev->rxq);
1175 status = usb_autopm_get_interface(dev->intf);
1176 if (status < 0)
1177 goto fail_halt;
1178 status = usb_clear_halt (dev->udev, dev->in);
1179 usb_autopm_put_interface(dev->intf);
1180 if (status < 0 &&
1181 status != -EPIPE &&
1182 status != -ESHUTDOWN) {
1183 if (netif_msg_rx_err (dev))
1184 fail_halt:
1185 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1186 status);
1187 } else {
1188 clear_bit (EVENT_RX_HALT, &dev->flags);
1189 tasklet_schedule (&dev->bh);
1190 }
1191 }
1192
1193 /* tasklet could resubmit itself forever if memory is tight */
1194 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1195 struct urb *urb = NULL;
1196 int resched = 1;
1197
1198 if (netif_running (dev->net))
1199 urb = usb_alloc_urb (0, GFP_KERNEL);
1200 else
1201 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1202 if (urb != NULL) {
1203 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1204 status = usb_autopm_get_interface(dev->intf);
1205 if (status < 0) {
1206 usb_free_urb(urb);
1207 goto fail_lowmem;
1208 }
1209 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1210 resched = 0;
1211 usb_autopm_put_interface(dev->intf);
1212 fail_lowmem:
1213 if (resched)
1214 tasklet_schedule (&dev->bh);
1215 }
1216 }
1217
1218 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1219 struct driver_info *info = dev->driver_info;
1220 int retval = 0;
1221
1222 clear_bit (EVENT_LINK_RESET, &dev->flags);
1223 status = usb_autopm_get_interface(dev->intf);
1224 if (status < 0)
1225 goto skip_reset;
1226 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1227 usb_autopm_put_interface(dev->intf);
1228 skip_reset:
1229 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1230 retval,
1231 dev->udev->bus->bus_name,
1232 dev->udev->devpath,
1233 info->description);
1234 } else {
1235 usb_autopm_put_interface(dev->intf);
1236 }
1237
1238 /* handle link change from link resetting */
1239 __handle_link_change(dev);
1240 }
1241
1242 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1243 __handle_link_change(dev);
1244
1245 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1246 __handle_set_rx_mode(dev);
1247
1248
1249 if (dev->flags)
1250 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1251 }
1252
1253 /*-------------------------------------------------------------------------*/
1254
tx_complete(struct urb * urb)1255 static void tx_complete (struct urb *urb)
1256 {
1257 struct sk_buff *skb = (struct sk_buff *) urb->context;
1258 struct skb_data *entry = (struct skb_data *) skb->cb;
1259 struct usbnet *dev = entry->dev;
1260
1261 if (urb->status == 0) {
1262 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->stats64);
1263 unsigned long flags;
1264
1265 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1266 stats64->tx_packets += entry->packets;
1267 stats64->tx_bytes += entry->length;
1268 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1269 } else {
1270 dev->net->stats.tx_errors++;
1271
1272 switch (urb->status) {
1273 case -EPIPE:
1274 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1275 break;
1276
1277 /* software-driven interface shutdown */
1278 case -ECONNRESET: // async unlink
1279 case -ESHUTDOWN: // hardware gone
1280 break;
1281
1282 /* like rx, tx gets controller i/o faults during hub_wq
1283 * delays and so it uses the same throttling mechanism.
1284 */
1285 case -EPROTO:
1286 case -ETIME:
1287 case -EILSEQ:
1288 usb_mark_last_busy(dev->udev);
1289 if (!timer_pending (&dev->delay)) {
1290 mod_timer (&dev->delay,
1291 jiffies + THROTTLE_JIFFIES);
1292 netif_dbg(dev, link, dev->net,
1293 "tx throttle %d\n", urb->status);
1294 }
1295 netif_stop_queue (dev->net);
1296 break;
1297 default:
1298 netif_dbg(dev, tx_err, dev->net,
1299 "tx err %d\n", entry->urb->status);
1300 break;
1301 }
1302 }
1303
1304 usb_autopm_put_interface_async(dev->intf);
1305 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1306 }
1307
1308 /*-------------------------------------------------------------------------*/
1309
usbnet_tx_timeout(struct net_device * net)1310 void usbnet_tx_timeout (struct net_device *net)
1311 {
1312 struct usbnet *dev = netdev_priv(net);
1313
1314 unlink_urbs (dev, &dev->txq);
1315 tasklet_schedule (&dev->bh);
1316 /* this needs to be handled individually because the generic layer
1317 * doesn't know what is sufficient and could not restore private
1318 * information if a remedy of an unconditional reset were used.
1319 */
1320 if (dev->driver_info->recover)
1321 (dev->driver_info->recover)(dev);
1322 }
1323 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1324
1325 /*-------------------------------------------------------------------------*/
1326
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1327 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1328 {
1329 unsigned num_sgs, total_len = 0;
1330 int i, s = 0;
1331
1332 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1333 if (num_sgs == 1)
1334 return 0;
1335
1336 /* reserve one for zero packet */
1337 urb->sg = kmalloc((num_sgs + 1) * sizeof(struct scatterlist),
1338 GFP_ATOMIC);
1339 if (!urb->sg)
1340 return -ENOMEM;
1341
1342 urb->num_sgs = num_sgs;
1343 sg_init_table(urb->sg, urb->num_sgs + 1);
1344
1345 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1346 total_len += skb_headlen(skb);
1347
1348 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1349 struct skb_frag_struct *f = &skb_shinfo(skb)->frags[i];
1350
1351 total_len += skb_frag_size(f);
1352 sg_set_page(&urb->sg[i + s], f->page.p, f->size,
1353 f->page_offset);
1354 }
1355 urb->transfer_buffer_length = total_len;
1356
1357 return 1;
1358 }
1359
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1360 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1361 struct net_device *net)
1362 {
1363 struct usbnet *dev = netdev_priv(net);
1364 unsigned int length;
1365 struct urb *urb = NULL;
1366 struct skb_data *entry;
1367 struct driver_info *info = dev->driver_info;
1368 unsigned long flags;
1369 int retval;
1370
1371 if (skb)
1372 skb_tx_timestamp(skb);
1373
1374 // some devices want funky USB-level framing, for
1375 // win32 driver (usually) and/or hardware quirks
1376 if (info->tx_fixup) {
1377 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1378 if (!skb) {
1379 /* packet collected; minidriver waiting for more */
1380 if (info->flags & FLAG_MULTI_PACKET)
1381 goto not_drop;
1382 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1383 goto drop;
1384 }
1385 }
1386
1387 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1388 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1389 goto drop;
1390 }
1391
1392 entry = (struct skb_data *) skb->cb;
1393 entry->urb = urb;
1394 entry->dev = dev;
1395
1396 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1397 skb->data, skb->len, tx_complete, skb);
1398 if (dev->can_dma_sg) {
1399 if (build_dma_sg(skb, urb) < 0)
1400 goto drop;
1401 }
1402 length = urb->transfer_buffer_length;
1403
1404 /* don't assume the hardware handles USB_ZERO_PACKET
1405 * NOTE: strictly conforming cdc-ether devices should expect
1406 * the ZLP here, but ignore the one-byte packet.
1407 * NOTE2: CDC NCM specification is different from CDC ECM when
1408 * handling ZLP/short packets, so cdc_ncm driver will make short
1409 * packet itself if needed.
1410 */
1411 if (length % dev->maxpacket == 0) {
1412 if (!(info->flags & FLAG_SEND_ZLP)) {
1413 if (!(info->flags & FLAG_MULTI_PACKET)) {
1414 length++;
1415 if (skb_tailroom(skb) && !urb->num_sgs) {
1416 skb->data[skb->len] = 0;
1417 __skb_put(skb, 1);
1418 } else if (urb->num_sgs)
1419 sg_set_buf(&urb->sg[urb->num_sgs++],
1420 dev->padding_pkt, 1);
1421 }
1422 } else
1423 urb->transfer_flags |= URB_ZERO_PACKET;
1424 }
1425 urb->transfer_buffer_length = length;
1426
1427 if (info->flags & FLAG_MULTI_PACKET) {
1428 /* Driver has set number of packets and a length delta.
1429 * Calculate the complete length and ensure that it's
1430 * positive.
1431 */
1432 entry->length += length;
1433 if (WARN_ON_ONCE(entry->length <= 0))
1434 entry->length = length;
1435 } else {
1436 usbnet_set_skb_tx_stats(skb, 1, length);
1437 }
1438
1439 spin_lock_irqsave(&dev->txq.lock, flags);
1440 retval = usb_autopm_get_interface_async(dev->intf);
1441 if (retval < 0) {
1442 spin_unlock_irqrestore(&dev->txq.lock, flags);
1443 goto drop;
1444 }
1445 if (netif_queue_stopped(net)) {
1446 usb_autopm_put_interface_async(dev->intf);
1447 spin_unlock_irqrestore(&dev->txq.lock, flags);
1448 goto drop;
1449 }
1450
1451 #ifdef CONFIG_PM
1452 /* if this triggers the device is still a sleep */
1453 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1454 /* transmission will be done in resume */
1455 usb_anchor_urb(urb, &dev->deferred);
1456 /* no use to process more packets */
1457 netif_stop_queue(net);
1458 usb_put_urb(urb);
1459 spin_unlock_irqrestore(&dev->txq.lock, flags);
1460 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1461 goto deferred;
1462 }
1463 #endif
1464
1465 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1466 case -EPIPE:
1467 netif_stop_queue (net);
1468 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1469 usb_autopm_put_interface_async(dev->intf);
1470 break;
1471 default:
1472 usb_autopm_put_interface_async(dev->intf);
1473 netif_dbg(dev, tx_err, dev->net,
1474 "tx: submit urb err %d\n", retval);
1475 break;
1476 case 0:
1477 netif_trans_update(net);
1478 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1479 if (dev->txq.qlen >= TX_QLEN (dev))
1480 netif_stop_queue (net);
1481 }
1482 spin_unlock_irqrestore (&dev->txq.lock, flags);
1483
1484 if (retval) {
1485 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1486 drop:
1487 dev->net->stats.tx_dropped++;
1488 not_drop:
1489 if (skb)
1490 dev_kfree_skb_any (skb);
1491 if (urb) {
1492 kfree(urb->sg);
1493 usb_free_urb(urb);
1494 }
1495 } else
1496 netif_dbg(dev, tx_queued, dev->net,
1497 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1498 #ifdef CONFIG_PM
1499 deferred:
1500 #endif
1501 return NETDEV_TX_OK;
1502 }
1503 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1504
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1505 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1506 {
1507 struct urb *urb;
1508 int i;
1509 int ret = 0;
1510
1511 /* don't refill the queue all at once */
1512 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1513 urb = usb_alloc_urb(0, flags);
1514 if (urb != NULL) {
1515 ret = rx_submit(dev, urb, flags);
1516 if (ret)
1517 goto err;
1518 } else {
1519 ret = -ENOMEM;
1520 goto err;
1521 }
1522 }
1523 err:
1524 return ret;
1525 }
1526
1527 /*-------------------------------------------------------------------------*/
1528
1529 // tasklet (work deferred from completions, in_irq) or timer
1530
usbnet_bh(unsigned long param)1531 static void usbnet_bh (unsigned long param)
1532 {
1533 struct usbnet *dev = (struct usbnet *) param;
1534 struct sk_buff *skb;
1535 struct skb_data *entry;
1536
1537 while ((skb = skb_dequeue (&dev->done))) {
1538 entry = (struct skb_data *) skb->cb;
1539 switch (entry->state) {
1540 case rx_done:
1541 entry->state = rx_cleanup;
1542 rx_process (dev, skb);
1543 continue;
1544 case tx_done:
1545 kfree(entry->urb->sg);
1546 case rx_cleanup:
1547 usb_free_urb (entry->urb);
1548 dev_kfree_skb (skb);
1549 continue;
1550 default:
1551 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1552 }
1553 }
1554
1555 /* restart RX again after disabling due to high error rate */
1556 clear_bit(EVENT_RX_KILL, &dev->flags);
1557
1558 /* waiting for all pending urbs to complete?
1559 * only then can we forgo submitting anew
1560 */
1561 if (waitqueue_active(&dev->wait)) {
1562 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1563 wake_up_all(&dev->wait);
1564
1565 // or are we maybe short a few urbs?
1566 } else if (netif_running (dev->net) &&
1567 netif_device_present (dev->net) &&
1568 netif_carrier_ok(dev->net) &&
1569 !timer_pending(&dev->delay) &&
1570 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1571 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1572 int temp = dev->rxq.qlen;
1573
1574 if (temp < RX_QLEN(dev)) {
1575 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1576 return;
1577 if (temp != dev->rxq.qlen)
1578 netif_dbg(dev, link, dev->net,
1579 "rxqlen %d --> %d\n",
1580 temp, dev->rxq.qlen);
1581 if (dev->rxq.qlen < RX_QLEN(dev))
1582 tasklet_schedule (&dev->bh);
1583 }
1584 if (dev->txq.qlen < TX_QLEN (dev))
1585 netif_wake_queue (dev->net);
1586 }
1587 }
1588
1589
1590 /*-------------------------------------------------------------------------
1591 *
1592 * USB Device Driver support
1593 *
1594 *-------------------------------------------------------------------------*/
1595
1596 // precondition: never called in_interrupt
1597
usbnet_disconnect(struct usb_interface * intf)1598 void usbnet_disconnect (struct usb_interface *intf)
1599 {
1600 struct usbnet *dev;
1601 struct usb_device *xdev;
1602 struct net_device *net;
1603
1604 dev = usb_get_intfdata(intf);
1605 usb_set_intfdata(intf, NULL);
1606 if (!dev)
1607 return;
1608
1609 xdev = interface_to_usbdev (intf);
1610
1611 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1612 intf->dev.driver->name,
1613 xdev->bus->bus_name, xdev->devpath,
1614 dev->driver_info->description);
1615
1616 net = dev->net;
1617 unregister_netdev (net);
1618
1619 cancel_work_sync(&dev->kevent);
1620
1621 usb_scuttle_anchored_urbs(&dev->deferred);
1622
1623 if (dev->driver_info->unbind)
1624 dev->driver_info->unbind (dev, intf);
1625
1626 usb_kill_urb(dev->interrupt);
1627 usb_free_urb(dev->interrupt);
1628 kfree(dev->padding_pkt);
1629
1630 free_percpu(dev->stats64);
1631 free_netdev(net);
1632 }
1633 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1634
1635 static const struct net_device_ops usbnet_netdev_ops = {
1636 .ndo_open = usbnet_open,
1637 .ndo_stop = usbnet_stop,
1638 .ndo_start_xmit = usbnet_start_xmit,
1639 .ndo_tx_timeout = usbnet_tx_timeout,
1640 .ndo_set_rx_mode = usbnet_set_rx_mode,
1641 .ndo_change_mtu = usbnet_change_mtu,
1642 .ndo_get_stats64 = usbnet_get_stats64,
1643 .ndo_set_mac_address = eth_mac_addr,
1644 .ndo_validate_addr = eth_validate_addr,
1645 };
1646
1647 /*-------------------------------------------------------------------------*/
1648
1649 // precondition: never called in_interrupt
1650
1651 static struct device_type wlan_type = {
1652 .name = "wlan",
1653 };
1654
1655 static struct device_type wwan_type = {
1656 .name = "wwan",
1657 };
1658
1659 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1660 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1661 {
1662 struct usbnet *dev;
1663 struct net_device *net;
1664 struct usb_host_interface *interface;
1665 struct driver_info *info;
1666 struct usb_device *xdev;
1667 int status;
1668 const char *name;
1669 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1670
1671 /* usbnet already took usb runtime pm, so have to enable the feature
1672 * for usb interface, otherwise usb_autopm_get_interface may return
1673 * failure if RUNTIME_PM is enabled.
1674 */
1675 if (!driver->supports_autosuspend) {
1676 driver->supports_autosuspend = 1;
1677 pm_runtime_enable(&udev->dev);
1678 }
1679
1680 name = udev->dev.driver->name;
1681 info = (struct driver_info *) prod->driver_info;
1682 if (!info) {
1683 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1684 return -ENODEV;
1685 }
1686 xdev = interface_to_usbdev (udev);
1687 interface = udev->cur_altsetting;
1688
1689 status = -ENOMEM;
1690
1691 // set up our own records
1692 net = alloc_etherdev(sizeof(*dev));
1693 if (!net)
1694 goto out;
1695
1696 /* netdev_printk() needs this so do it as early as possible */
1697 SET_NETDEV_DEV(net, &udev->dev);
1698
1699 dev = netdev_priv(net);
1700 dev->udev = xdev;
1701 dev->intf = udev;
1702 dev->driver_info = info;
1703 dev->driver_name = name;
1704
1705 dev->stats64 = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1706 if (!dev->stats64)
1707 goto out0;
1708
1709 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1710 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1711 init_waitqueue_head(&dev->wait);
1712 skb_queue_head_init (&dev->rxq);
1713 skb_queue_head_init (&dev->txq);
1714 skb_queue_head_init (&dev->done);
1715 skb_queue_head_init(&dev->rxq_pause);
1716 dev->bh.func = usbnet_bh;
1717 dev->bh.data = (unsigned long) dev;
1718 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1719 init_usb_anchor(&dev->deferred);
1720 dev->delay.function = usbnet_bh;
1721 dev->delay.data = (unsigned long) dev;
1722 init_timer (&dev->delay);
1723 mutex_init (&dev->phy_mutex);
1724 mutex_init(&dev->interrupt_mutex);
1725 dev->interrupt_count = 0;
1726
1727 dev->net = net;
1728 strcpy (net->name, "usb%d");
1729 memcpy (net->dev_addr, node_id, sizeof node_id);
1730
1731 /* rx and tx sides can use different message sizes;
1732 * bind() should set rx_urb_size in that case.
1733 */
1734 dev->hard_mtu = net->mtu + net->hard_header_len;
1735 net->min_mtu = 0;
1736 net->max_mtu = ETH_MAX_MTU;
1737
1738 net->netdev_ops = &usbnet_netdev_ops;
1739 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1740 net->ethtool_ops = &usbnet_ethtool_ops;
1741
1742 // allow device-specific bind/init procedures
1743 // NOTE net->name still not usable ...
1744 if (info->bind) {
1745 status = info->bind (dev, udev);
1746 if (status < 0)
1747 goto out1;
1748
1749 // heuristic: "usb%d" for links we know are two-host,
1750 // else "eth%d" when there's reasonable doubt. userspace
1751 // can rename the link if it knows better.
1752 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1753 ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1754 (net->dev_addr [0] & 0x02) == 0))
1755 strcpy (net->name, "eth%d");
1756 /* WLAN devices should always be named "wlan%d" */
1757 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1758 strcpy(net->name, "wlan%d");
1759 /* WWAN devices should always be named "wwan%d" */
1760 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1761 strcpy(net->name, "wwan%d");
1762
1763 /* devices that cannot do ARP */
1764 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1765 net->flags |= IFF_NOARP;
1766
1767 /* maybe the remote can't receive an Ethernet MTU */
1768 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1769 net->mtu = dev->hard_mtu - net->hard_header_len;
1770 } else if (!info->in || !info->out)
1771 status = usbnet_get_endpoints (dev, udev);
1772 else {
1773 dev->in = usb_rcvbulkpipe (xdev, info->in);
1774 dev->out = usb_sndbulkpipe (xdev, info->out);
1775 if (!(info->flags & FLAG_NO_SETINT))
1776 status = usb_set_interface (xdev,
1777 interface->desc.bInterfaceNumber,
1778 interface->desc.bAlternateSetting);
1779 else
1780 status = 0;
1781
1782 }
1783 if (status >= 0 && dev->status)
1784 status = init_status (dev, udev);
1785 if (status < 0)
1786 goto out3;
1787
1788 if (!dev->rx_urb_size)
1789 dev->rx_urb_size = dev->hard_mtu;
1790 dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1791
1792 /* let userspace know we have a random address */
1793 if (ether_addr_equal(net->dev_addr, node_id))
1794 net->addr_assign_type = NET_ADDR_RANDOM;
1795
1796 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1797 SET_NETDEV_DEVTYPE(net, &wlan_type);
1798 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1799 SET_NETDEV_DEVTYPE(net, &wwan_type);
1800
1801 /* initialize max rx_qlen and tx_qlen */
1802 usbnet_update_max_qlen(dev);
1803
1804 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1805 !(info->flags & FLAG_MULTI_PACKET)) {
1806 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1807 if (!dev->padding_pkt) {
1808 status = -ENOMEM;
1809 goto out4;
1810 }
1811 }
1812
1813 status = register_netdev (net);
1814 if (status)
1815 goto out5;
1816 netif_info(dev, probe, dev->net,
1817 "register '%s' at usb-%s-%s, %s, %pM\n",
1818 udev->dev.driver->name,
1819 xdev->bus->bus_name, xdev->devpath,
1820 dev->driver_info->description,
1821 net->dev_addr);
1822
1823 // ok, it's ready to go.
1824 usb_set_intfdata (udev, dev);
1825
1826 netif_device_attach (net);
1827
1828 if (dev->driver_info->flags & FLAG_LINK_INTR)
1829 usbnet_link_change(dev, 0, 0);
1830
1831 return 0;
1832
1833 out5:
1834 kfree(dev->padding_pkt);
1835 out4:
1836 usb_free_urb(dev->interrupt);
1837 out3:
1838 if (info->unbind)
1839 info->unbind (dev, udev);
1840 out1:
1841 /* subdrivers must undo all they did in bind() if they
1842 * fail it, but we may fail later and a deferred kevent
1843 * may trigger an error resubmitting itself and, worse,
1844 * schedule a timer. So we kill it all just in case.
1845 */
1846 cancel_work_sync(&dev->kevent);
1847 del_timer_sync(&dev->delay);
1848 free_percpu(dev->stats64);
1849 out0:
1850 free_netdev(net);
1851 out:
1852 return status;
1853 }
1854 EXPORT_SYMBOL_GPL(usbnet_probe);
1855
1856 /*-------------------------------------------------------------------------*/
1857
1858 /*
1859 * suspend the whole driver as soon as the first interface is suspended
1860 * resume only when the last interface is resumed
1861 */
1862
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1863 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1864 {
1865 struct usbnet *dev = usb_get_intfdata(intf);
1866
1867 if (!dev->suspend_count++) {
1868 spin_lock_irq(&dev->txq.lock);
1869 /* don't autosuspend while transmitting */
1870 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1871 dev->suspend_count--;
1872 spin_unlock_irq(&dev->txq.lock);
1873 return -EBUSY;
1874 } else {
1875 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1876 spin_unlock_irq(&dev->txq.lock);
1877 }
1878 /*
1879 * accelerate emptying of the rx and queues, to avoid
1880 * having everything error out.
1881 */
1882 netif_device_detach (dev->net);
1883 usbnet_terminate_urbs(dev);
1884 __usbnet_status_stop_force(dev);
1885
1886 /*
1887 * reattach so runtime management can use and
1888 * wake the device
1889 */
1890 netif_device_attach (dev->net);
1891 }
1892 return 0;
1893 }
1894 EXPORT_SYMBOL_GPL(usbnet_suspend);
1895
usbnet_resume(struct usb_interface * intf)1896 int usbnet_resume (struct usb_interface *intf)
1897 {
1898 struct usbnet *dev = usb_get_intfdata(intf);
1899 struct sk_buff *skb;
1900 struct urb *res;
1901 int retval;
1902
1903 if (!--dev->suspend_count) {
1904 /* resume interrupt URB if it was previously submitted */
1905 __usbnet_status_start_force(dev, GFP_NOIO);
1906
1907 spin_lock_irq(&dev->txq.lock);
1908 while ((res = usb_get_from_anchor(&dev->deferred))) {
1909
1910 skb = (struct sk_buff *)res->context;
1911 retval = usb_submit_urb(res, GFP_ATOMIC);
1912 if (retval < 0) {
1913 dev_kfree_skb_any(skb);
1914 kfree(res->sg);
1915 usb_free_urb(res);
1916 usb_autopm_put_interface_async(dev->intf);
1917 } else {
1918 netif_trans_update(dev->net);
1919 __skb_queue_tail(&dev->txq, skb);
1920 }
1921 }
1922
1923 smp_mb();
1924 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1925 spin_unlock_irq(&dev->txq.lock);
1926
1927 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1928 /* handle remote wakeup ASAP
1929 * we cannot race against stop
1930 */
1931 if (netif_device_present(dev->net) &&
1932 !timer_pending(&dev->delay) &&
1933 !test_bit(EVENT_RX_HALT, &dev->flags))
1934 rx_alloc_submit(dev, GFP_NOIO);
1935
1936 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1937 netif_tx_wake_all_queues(dev->net);
1938 tasklet_schedule (&dev->bh);
1939 }
1940 }
1941
1942 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1943 usb_autopm_get_interface_no_resume(intf);
1944
1945 return 0;
1946 }
1947 EXPORT_SYMBOL_GPL(usbnet_resume);
1948
1949 /*
1950 * Either a subdriver implements manage_power, then it is assumed to always
1951 * be ready to be suspended or it reports the readiness to be suspended
1952 * explicitly
1953 */
usbnet_device_suggests_idle(struct usbnet * dev)1954 void usbnet_device_suggests_idle(struct usbnet *dev)
1955 {
1956 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1957 dev->intf->needs_remote_wakeup = 1;
1958 usb_autopm_put_interface_async(dev->intf);
1959 }
1960 }
1961 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1962
1963 /*
1964 * For devices that can do without special commands
1965 */
usbnet_manage_power(struct usbnet * dev,int on)1966 int usbnet_manage_power(struct usbnet *dev, int on)
1967 {
1968 dev->intf->needs_remote_wakeup = on;
1969 return 0;
1970 }
1971 EXPORT_SYMBOL(usbnet_manage_power);
1972
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)1973 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1974 {
1975 /* update link after link is reseted */
1976 if (link && !need_reset)
1977 netif_carrier_on(dev->net);
1978 else
1979 netif_carrier_off(dev->net);
1980
1981 if (need_reset && link)
1982 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1983 else
1984 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1985 }
1986 EXPORT_SYMBOL(usbnet_link_change);
1987
1988 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)1989 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1990 u16 value, u16 index, void *data, u16 size)
1991 {
1992 void *buf = NULL;
1993 int err = -ENOMEM;
1994
1995 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
1996 " value=0x%04x index=0x%04x size=%d\n",
1997 cmd, reqtype, value, index, size);
1998
1999 if (size) {
2000 buf = kmalloc(size, GFP_KERNEL);
2001 if (!buf)
2002 goto out;
2003 }
2004
2005 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2006 cmd, reqtype, value, index, buf, size,
2007 USB_CTRL_GET_TIMEOUT);
2008 if (err > 0 && err <= size) {
2009 if (data)
2010 memcpy(data, buf, err);
2011 else
2012 netdev_dbg(dev->net,
2013 "Huh? Data requested but thrown away.\n");
2014 }
2015 kfree(buf);
2016 out:
2017 return err;
2018 }
2019
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2020 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2021 u16 value, u16 index, const void *data,
2022 u16 size)
2023 {
2024 void *buf = NULL;
2025 int err = -ENOMEM;
2026
2027 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2028 " value=0x%04x index=0x%04x size=%d\n",
2029 cmd, reqtype, value, index, size);
2030
2031 if (data) {
2032 buf = kmemdup(data, size, GFP_KERNEL);
2033 if (!buf)
2034 goto out;
2035 } else {
2036 if (size) {
2037 WARN_ON_ONCE(1);
2038 err = -EINVAL;
2039 goto out;
2040 }
2041 }
2042
2043 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2044 cmd, reqtype, value, index, buf, size,
2045 USB_CTRL_SET_TIMEOUT);
2046 kfree(buf);
2047
2048 out:
2049 return err;
2050 }
2051
2052 /*
2053 * The function can't be called inside suspend/resume callback,
2054 * otherwise deadlock will be caused.
2055 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2056 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2057 u16 value, u16 index, void *data, u16 size)
2058 {
2059 int ret;
2060
2061 if (usb_autopm_get_interface(dev->intf) < 0)
2062 return -ENODEV;
2063 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2064 data, size);
2065 usb_autopm_put_interface(dev->intf);
2066 return ret;
2067 }
2068 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2069
2070 /*
2071 * The function can't be called inside suspend/resume callback,
2072 * otherwise deadlock will be caused.
2073 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2074 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2075 u16 value, u16 index, const void *data, u16 size)
2076 {
2077 int ret;
2078
2079 if (usb_autopm_get_interface(dev->intf) < 0)
2080 return -ENODEV;
2081 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2082 data, size);
2083 usb_autopm_put_interface(dev->intf);
2084 return ret;
2085 }
2086 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2087
2088 /*
2089 * The function can be called inside suspend/resume callback safely
2090 * and should only be called by suspend/resume callback generally.
2091 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2092 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2093 u16 value, u16 index, void *data, u16 size)
2094 {
2095 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2096 data, size);
2097 }
2098 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2099
2100 /*
2101 * The function can be called inside suspend/resume callback safely
2102 * and should only be called by suspend/resume callback generally.
2103 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2104 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2105 u16 value, u16 index, const void *data,
2106 u16 size)
2107 {
2108 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2109 data, size);
2110 }
2111 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2112
usbnet_async_cmd_cb(struct urb * urb)2113 static void usbnet_async_cmd_cb(struct urb *urb)
2114 {
2115 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2116 int status = urb->status;
2117
2118 if (status < 0)
2119 dev_dbg(&urb->dev->dev, "%s failed with %d",
2120 __func__, status);
2121
2122 kfree(req);
2123 usb_free_urb(urb);
2124 }
2125
2126 /*
2127 * The caller must make sure that device can't be put into suspend
2128 * state until the control URB completes.
2129 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2130 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2131 u16 value, u16 index, const void *data, u16 size)
2132 {
2133 struct usb_ctrlrequest *req = NULL;
2134 struct urb *urb;
2135 int err = -ENOMEM;
2136 void *buf = NULL;
2137
2138 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2139 " value=0x%04x index=0x%04x size=%d\n",
2140 cmd, reqtype, value, index, size);
2141
2142 urb = usb_alloc_urb(0, GFP_ATOMIC);
2143 if (!urb)
2144 goto fail;
2145
2146 if (data) {
2147 buf = kmemdup(data, size, GFP_ATOMIC);
2148 if (!buf) {
2149 netdev_err(dev->net, "Error allocating buffer"
2150 " in %s!\n", __func__);
2151 goto fail_free;
2152 }
2153 }
2154
2155 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2156 if (!req)
2157 goto fail_free_buf;
2158
2159 req->bRequestType = reqtype;
2160 req->bRequest = cmd;
2161 req->wValue = cpu_to_le16(value);
2162 req->wIndex = cpu_to_le16(index);
2163 req->wLength = cpu_to_le16(size);
2164
2165 usb_fill_control_urb(urb, dev->udev,
2166 usb_sndctrlpipe(dev->udev, 0),
2167 (void *)req, buf, size,
2168 usbnet_async_cmd_cb, req);
2169 urb->transfer_flags |= URB_FREE_BUFFER;
2170
2171 err = usb_submit_urb(urb, GFP_ATOMIC);
2172 if (err < 0) {
2173 netdev_err(dev->net, "Error submitting the control"
2174 " message: status=%d\n", err);
2175 goto fail_free;
2176 }
2177 return 0;
2178
2179 fail_free_buf:
2180 kfree(buf);
2181 fail_free:
2182 kfree(req);
2183 usb_free_urb(urb);
2184 fail:
2185 return err;
2186
2187 }
2188 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2189 /*-------------------------------------------------------------------------*/
2190
usbnet_init(void)2191 static int __init usbnet_init(void)
2192 {
2193 /* Compiler should optimize this out. */
2194 BUILD_BUG_ON(
2195 FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
2196
2197 eth_random_addr(node_id);
2198 return 0;
2199 }
2200 module_init(usbnet_init);
2201
usbnet_exit(void)2202 static void __exit usbnet_exit(void)
2203 {
2204 }
2205 module_exit(usbnet_exit);
2206
2207 MODULE_AUTHOR("David Brownell");
2208 MODULE_DESCRIPTION("USB network driver framework");
2209 MODULE_LICENSE("GPL");
2210