1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * USB Network driver infrastructure
4 * Copyright (C) 2000-2005 by David Brownell
5 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
6 */
7
8 /*
9 * This is a generic "USB networking" framework that works with several
10 * kinds of full and high speed networking devices: host-to-host cables,
11 * smart usb peripherals, and actual Ethernet adapters.
12 *
13 * These devices usually differ in terms of control protocols (if they
14 * even have one!) and sometimes they define new framing to wrap or batch
15 * Ethernet packets. Otherwise, they talk to USB pretty much the same,
16 * so interface (un)binding, endpoint I/O queues, fault handling, and other
17 * issues can usefully be addressed by this framework.
18 */
19
20 // #define DEBUG // error path messages, extra info
21 // #define VERBOSE // more; success messages
22
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/ctype.h>
28 #include <linux/ethtool.h>
29 #include <linux/workqueue.h>
30 #include <linux/mii.h>
31 #include <linux/usb.h>
32 #include <linux/usb/usbnet.h>
33 #include <linux/slab.h>
34 #include <linux/kernel.h>
35 #include <linux/pm_runtime.h>
36
37 /*-------------------------------------------------------------------------*/
38
39 /*
40 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
41 * Several dozen bytes of IPv4 data can fit in two such transactions.
42 * One maximum size Ethernet packet takes twenty four of them.
43 * For high speed, each frame comfortably fits almost 36 max size
44 * Ethernet packets (so queues should be bigger).
45 *
46 * The goal is to let the USB host controller be busy for 5msec or
47 * more before an irq is required, under load. Jumbograms change
48 * the equation.
49 */
50 #define MAX_QUEUE_MEMORY (60 * 1518)
51 #define RX_QLEN(dev) ((dev)->rx_qlen)
52 #define TX_QLEN(dev) ((dev)->tx_qlen)
53
54 // reawaken network queue this soon after stopping; else watchdog barks
55 #define TX_TIMEOUT_JIFFIES (5*HZ)
56
57 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
58 * us (it polls at HZ/4 usually) before we report too many false errors.
59 */
60 #define THROTTLE_JIFFIES (HZ/8)
61
62 // between wakeups
63 #define UNLINK_TIMEOUT_MS 3
64
65 /*-------------------------------------------------------------------------*/
66
67 // randomly generated ethernet address
68 static u8 node_id [ETH_ALEN];
69
70 /* use ethtool to change the level for any given device */
71 static int msg_level = -1;
72 module_param (msg_level, int, 0);
73 MODULE_PARM_DESC (msg_level, "Override default message level");
74
75 /*-------------------------------------------------------------------------*/
76
77 static const char * const usbnet_event_names[] = {
78 [EVENT_TX_HALT] = "EVENT_TX_HALT",
79 [EVENT_RX_HALT] = "EVENT_RX_HALT",
80 [EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
81 [EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
82 [EVENT_LINK_RESET] = "EVENT_LINK_RESET",
83 [EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
84 [EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
85 [EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
86 [EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
87 [EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
88 [EVENT_RX_KILL] = "EVENT_RX_KILL",
89 [EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
90 [EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
91 [EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
92 };
93
94 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)95 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
96 {
97 int tmp;
98 struct usb_host_interface *alt = NULL;
99 struct usb_host_endpoint *in = NULL, *out = NULL;
100 struct usb_host_endpoint *status = NULL;
101
102 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
103 unsigned ep;
104
105 in = out = status = NULL;
106 alt = intf->altsetting + tmp;
107
108 /* take the first altsetting with in-bulk + out-bulk;
109 * remember any status endpoint, just in case;
110 * ignore other endpoints and altsettings.
111 */
112 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
113 struct usb_host_endpoint *e;
114 int intr = 0;
115
116 e = alt->endpoint + ep;
117
118 /* ignore endpoints which cannot transfer data */
119 if (!usb_endpoint_maxp(&e->desc))
120 continue;
121
122 switch (e->desc.bmAttributes) {
123 case USB_ENDPOINT_XFER_INT:
124 if (!usb_endpoint_dir_in(&e->desc))
125 continue;
126 intr = 1;
127 fallthrough;
128 case USB_ENDPOINT_XFER_BULK:
129 break;
130 default:
131 continue;
132 }
133 if (usb_endpoint_dir_in(&e->desc)) {
134 if (!intr && !in)
135 in = e;
136 else if (intr && !status)
137 status = e;
138 } else {
139 if (!out)
140 out = e;
141 }
142 }
143 if (in && out)
144 break;
145 }
146 if (!alt || !in || !out)
147 return -EINVAL;
148
149 if (alt->desc.bAlternateSetting != 0 ||
150 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
151 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
152 alt->desc.bAlternateSetting);
153 if (tmp < 0)
154 return tmp;
155 }
156
157 dev->in = usb_rcvbulkpipe (dev->udev,
158 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
159 dev->out = usb_sndbulkpipe (dev->udev,
160 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
161 dev->status = status;
162 return 0;
163 }
164 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
165
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)166 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
167 {
168 u8 addr[ETH_ALEN];
169 int tmp = -1, ret;
170 unsigned char buf [13];
171
172 ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
173 if (ret == 12)
174 tmp = hex2bin(addr, buf, 6);
175 if (tmp < 0) {
176 dev_dbg(&dev->udev->dev,
177 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
178 if (ret >= 0)
179 ret = -EINVAL;
180 return ret;
181 }
182 eth_hw_addr_set(dev->net, addr);
183 return 0;
184 }
185 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
186
intr_complete(struct urb * urb)187 static void intr_complete (struct urb *urb)
188 {
189 struct usbnet *dev = urb->context;
190 int status = urb->status;
191
192 switch (status) {
193 /* success */
194 case 0:
195 dev->driver_info->status(dev, urb);
196 break;
197
198 /* software-driven interface shutdown */
199 case -ENOENT: /* urb killed */
200 case -ESHUTDOWN: /* hardware gone */
201 netif_dbg(dev, ifdown, dev->net,
202 "intr shutdown, code %d\n", status);
203 return;
204
205 /* NOTE: not throttling like RX/TX, since this endpoint
206 * already polls infrequently
207 */
208 default:
209 netdev_dbg(dev->net, "intr status %d\n", status);
210 break;
211 }
212
213 status = usb_submit_urb (urb, GFP_ATOMIC);
214 if (status != 0)
215 netif_err(dev, timer, dev->net,
216 "intr resubmit --> %d\n", status);
217 }
218
init_status(struct usbnet * dev,struct usb_interface * intf)219 static int init_status (struct usbnet *dev, struct usb_interface *intf)
220 {
221 char *buf = NULL;
222 unsigned pipe = 0;
223 unsigned maxp;
224 unsigned period;
225
226 if (!dev->driver_info->status)
227 return 0;
228
229 pipe = usb_rcvintpipe (dev->udev,
230 dev->status->desc.bEndpointAddress
231 & USB_ENDPOINT_NUMBER_MASK);
232 maxp = usb_maxpacket (dev->udev, pipe, 0);
233
234 /* avoid 1 msec chatter: min 8 msec poll rate */
235 period = max ((int) dev->status->desc.bInterval,
236 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
237
238 buf = kmalloc (maxp, GFP_KERNEL);
239 if (buf) {
240 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
241 if (!dev->interrupt) {
242 kfree (buf);
243 return -ENOMEM;
244 } else {
245 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
246 buf, maxp, intr_complete, dev, period);
247 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
248 dev_dbg(&intf->dev,
249 "status ep%din, %d bytes period %d\n",
250 usb_pipeendpoint(pipe), maxp, period);
251 }
252 }
253 return 0;
254 }
255
256 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)257 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
258 {
259 int ret = 0;
260
261 WARN_ON_ONCE(dev->interrupt == NULL);
262 if (dev->interrupt) {
263 mutex_lock(&dev->interrupt_mutex);
264
265 if (++dev->interrupt_count == 1)
266 ret = usb_submit_urb(dev->interrupt, mem_flags);
267
268 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
269 dev->interrupt_count);
270 mutex_unlock(&dev->interrupt_mutex);
271 }
272 return ret;
273 }
274 EXPORT_SYMBOL_GPL(usbnet_status_start);
275
276 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)277 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
278 {
279 int ret = 0;
280
281 mutex_lock(&dev->interrupt_mutex);
282 if (dev->interrupt_count) {
283 ret = usb_submit_urb(dev->interrupt, mem_flags);
284 dev_dbg(&dev->udev->dev,
285 "submitted interrupt URB for resume\n");
286 }
287 mutex_unlock(&dev->interrupt_mutex);
288 return ret;
289 }
290
291 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)292 void usbnet_status_stop(struct usbnet *dev)
293 {
294 if (dev->interrupt) {
295 mutex_lock(&dev->interrupt_mutex);
296 WARN_ON(dev->interrupt_count == 0);
297
298 if (dev->interrupt_count && --dev->interrupt_count == 0)
299 usb_kill_urb(dev->interrupt);
300
301 dev_dbg(&dev->udev->dev,
302 "decremented interrupt URB count to %d\n",
303 dev->interrupt_count);
304 mutex_unlock(&dev->interrupt_mutex);
305 }
306 }
307 EXPORT_SYMBOL_GPL(usbnet_status_stop);
308
309 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)310 static void __usbnet_status_stop_force(struct usbnet *dev)
311 {
312 if (dev->interrupt) {
313 mutex_lock(&dev->interrupt_mutex);
314 usb_kill_urb(dev->interrupt);
315 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
316 mutex_unlock(&dev->interrupt_mutex);
317 }
318 }
319
320 /* Passes this packet up the stack, updating its accounting.
321 * Some link protocols batch packets, so their rx_fixup paths
322 * can return clones as well as just modify the original skb.
323 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)324 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
325 {
326 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
327 unsigned long flags;
328 int status;
329
330 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
331 skb_queue_tail(&dev->rxq_pause, skb);
332 return;
333 }
334
335 /* only update if unset to allow minidriver rx_fixup override */
336 if (skb->protocol == 0)
337 skb->protocol = eth_type_trans (skb, dev->net);
338
339 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
340 stats64->rx_packets++;
341 stats64->rx_bytes += skb->len;
342 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
343
344 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
345 skb->len + sizeof (struct ethhdr), skb->protocol);
346 memset (skb->cb, 0, sizeof (struct skb_data));
347
348 if (skb_defer_rx_timestamp(skb))
349 return;
350
351 status = netif_rx (skb);
352 if (status != NET_RX_SUCCESS)
353 netif_dbg(dev, rx_err, dev->net,
354 "netif_rx status %d\n", status);
355 }
356 EXPORT_SYMBOL_GPL(usbnet_skb_return);
357
358 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)359 void usbnet_update_max_qlen(struct usbnet *dev)
360 {
361 enum usb_device_speed speed = dev->udev->speed;
362
363 if (!dev->rx_urb_size || !dev->hard_mtu)
364 goto insanity;
365 switch (speed) {
366 case USB_SPEED_HIGH:
367 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
368 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
369 break;
370 case USB_SPEED_SUPER:
371 case USB_SPEED_SUPER_PLUS:
372 /*
373 * Not take default 5ms qlen for super speed HC to
374 * save memory, and iperf tests show 2.5ms qlen can
375 * work well
376 */
377 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
378 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
379 break;
380 default:
381 insanity:
382 dev->rx_qlen = dev->tx_qlen = 4;
383 }
384 }
385 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
386
387
388 /*-------------------------------------------------------------------------
389 *
390 * Network Device Driver (peer link to "Host Device", from USB host)
391 *
392 *-------------------------------------------------------------------------*/
393
usbnet_change_mtu(struct net_device * net,int new_mtu)394 int usbnet_change_mtu (struct net_device *net, int new_mtu)
395 {
396 struct usbnet *dev = netdev_priv(net);
397 int ll_mtu = new_mtu + net->hard_header_len;
398 int old_hard_mtu = dev->hard_mtu;
399 int old_rx_urb_size = dev->rx_urb_size;
400
401 // no second zero-length packet read wanted after mtu-sized packets
402 if ((ll_mtu % dev->maxpacket) == 0)
403 return -EDOM;
404 net->mtu = new_mtu;
405
406 dev->hard_mtu = net->mtu + net->hard_header_len;
407 if (dev->rx_urb_size == old_hard_mtu) {
408 dev->rx_urb_size = dev->hard_mtu;
409 if (dev->rx_urb_size > old_rx_urb_size) {
410 usbnet_pause_rx(dev);
411 usbnet_unlink_rx_urbs(dev);
412 usbnet_resume_rx(dev);
413 }
414 }
415
416 /* max qlen depend on hard_mtu and rx_urb_size */
417 usbnet_update_max_qlen(dev);
418
419 return 0;
420 }
421 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
422
423 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)424 static void __usbnet_queue_skb(struct sk_buff_head *list,
425 struct sk_buff *newsk, enum skb_state state)
426 {
427 struct skb_data *entry = (struct skb_data *) newsk->cb;
428
429 __skb_queue_tail(list, newsk);
430 entry->state = state;
431 }
432
433 /*-------------------------------------------------------------------------*/
434
435 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
436 * completion callbacks. 2.5 should have fixed those bugs...
437 */
438
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)439 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
440 struct sk_buff_head *list, enum skb_state state)
441 {
442 unsigned long flags;
443 enum skb_state old_state;
444 struct skb_data *entry = (struct skb_data *) skb->cb;
445
446 spin_lock_irqsave(&list->lock, flags);
447 old_state = entry->state;
448 entry->state = state;
449 __skb_unlink(skb, list);
450
451 /* defer_bh() is never called with list == &dev->done.
452 * spin_lock_nested() tells lockdep that it is OK to take
453 * dev->done.lock here with list->lock held.
454 */
455 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
456
457 __skb_queue_tail(&dev->done, skb);
458 if (dev->done.qlen == 1)
459 tasklet_schedule(&dev->bh);
460 spin_unlock(&dev->done.lock);
461 spin_unlock_irqrestore(&list->lock, flags);
462 return old_state;
463 }
464
465 /* some work can't be done in tasklets, so we use keventd
466 *
467 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
468 * but tasklet_schedule() doesn't. hope the failure is rare.
469 */
usbnet_defer_kevent(struct usbnet * dev,int work)470 void usbnet_defer_kevent (struct usbnet *dev, int work)
471 {
472 set_bit (work, &dev->flags);
473 if (!schedule_work (&dev->kevent))
474 netdev_dbg(dev->net, "kevent %s may have been dropped\n", usbnet_event_names[work]);
475 else
476 netdev_dbg(dev->net, "kevent %s scheduled\n", usbnet_event_names[work]);
477 }
478 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
479
480 /*-------------------------------------------------------------------------*/
481
482 static void rx_complete (struct urb *urb);
483
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)484 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
485 {
486 struct sk_buff *skb;
487 struct skb_data *entry;
488 int retval = 0;
489 unsigned long lockflags;
490 size_t size = dev->rx_urb_size;
491
492 /* prevent rx skb allocation when error ratio is high */
493 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
494 usb_free_urb(urb);
495 return -ENOLINK;
496 }
497
498 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
499 skb = __netdev_alloc_skb(dev->net, size, flags);
500 else
501 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
502 if (!skb) {
503 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
504 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
505 usb_free_urb (urb);
506 return -ENOMEM;
507 }
508
509 entry = (struct skb_data *) skb->cb;
510 entry->urb = urb;
511 entry->dev = dev;
512 entry->length = 0;
513
514 usb_fill_bulk_urb (urb, dev->udev, dev->in,
515 skb->data, size, rx_complete, skb);
516
517 spin_lock_irqsave (&dev->rxq.lock, lockflags);
518
519 if (netif_running (dev->net) &&
520 netif_device_present (dev->net) &&
521 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
522 !test_bit (EVENT_RX_HALT, &dev->flags) &&
523 !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
524 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
525 case -EPIPE:
526 usbnet_defer_kevent (dev, EVENT_RX_HALT);
527 break;
528 case -ENOMEM:
529 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
530 break;
531 case -ENODEV:
532 netif_dbg(dev, ifdown, dev->net, "device gone\n");
533 netif_device_detach (dev->net);
534 break;
535 case -EHOSTUNREACH:
536 retval = -ENOLINK;
537 break;
538 default:
539 netif_dbg(dev, rx_err, dev->net,
540 "rx submit, %d\n", retval);
541 tasklet_schedule (&dev->bh);
542 break;
543 case 0:
544 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
545 }
546 } else {
547 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
548 retval = -ENOLINK;
549 }
550 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
551 if (retval) {
552 dev_kfree_skb_any (skb);
553 usb_free_urb (urb);
554 }
555 return retval;
556 }
557
558
559 /*-------------------------------------------------------------------------*/
560
rx_process(struct usbnet * dev,struct sk_buff * skb)561 static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
562 {
563 if (dev->driver_info->rx_fixup &&
564 !dev->driver_info->rx_fixup (dev, skb)) {
565 /* With RX_ASSEMBLE, rx_fixup() must update counters */
566 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
567 dev->net->stats.rx_errors++;
568 goto done;
569 }
570 // else network stack removes extra byte if we forced a short packet
571
572 /* all data was already cloned from skb inside the driver */
573 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
574 goto done;
575
576 if (skb->len < ETH_HLEN) {
577 dev->net->stats.rx_errors++;
578 dev->net->stats.rx_length_errors++;
579 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
580 } else {
581 usbnet_skb_return(dev, skb);
582 return;
583 }
584
585 done:
586 skb_queue_tail(&dev->done, skb);
587 }
588
589 /*-------------------------------------------------------------------------*/
590
rx_complete(struct urb * urb)591 static void rx_complete (struct urb *urb)
592 {
593 struct sk_buff *skb = (struct sk_buff *) urb->context;
594 struct skb_data *entry = (struct skb_data *) skb->cb;
595 struct usbnet *dev = entry->dev;
596 int urb_status = urb->status;
597 enum skb_state state;
598
599 skb_put (skb, urb->actual_length);
600 state = rx_done;
601 entry->urb = NULL;
602
603 switch (urb_status) {
604 /* success */
605 case 0:
606 break;
607
608 /* stalls need manual reset. this is rare ... except that
609 * when going through USB 2.0 TTs, unplug appears this way.
610 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
611 * storm, recovering as needed.
612 */
613 case -EPIPE:
614 dev->net->stats.rx_errors++;
615 usbnet_defer_kevent (dev, EVENT_RX_HALT);
616 fallthrough;
617
618 /* software-driven interface shutdown */
619 case -ECONNRESET: /* async unlink */
620 case -ESHUTDOWN: /* hardware gone */
621 netif_dbg(dev, ifdown, dev->net,
622 "rx shutdown, code %d\n", urb_status);
623 goto block;
624
625 /* we get controller i/o faults during hub_wq disconnect() delays.
626 * throttle down resubmits, to avoid log floods; just temporarily,
627 * so we still recover when the fault isn't a hub_wq delay.
628 */
629 case -EPROTO:
630 case -ETIME:
631 case -EILSEQ:
632 dev->net->stats.rx_errors++;
633 if (!timer_pending (&dev->delay)) {
634 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
635 netif_dbg(dev, link, dev->net,
636 "rx throttle %d\n", urb_status);
637 }
638 block:
639 state = rx_cleanup;
640 entry->urb = urb;
641 urb = NULL;
642 break;
643
644 /* data overrun ... flush fifo? */
645 case -EOVERFLOW:
646 dev->net->stats.rx_over_errors++;
647 fallthrough;
648
649 default:
650 state = rx_cleanup;
651 dev->net->stats.rx_errors++;
652 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
653 break;
654 }
655
656 /* stop rx if packet error rate is high */
657 if (++dev->pkt_cnt > 30) {
658 dev->pkt_cnt = 0;
659 dev->pkt_err = 0;
660 } else {
661 if (state == rx_cleanup)
662 dev->pkt_err++;
663 if (dev->pkt_err > 20)
664 set_bit(EVENT_RX_KILL, &dev->flags);
665 }
666
667 state = defer_bh(dev, skb, &dev->rxq, state);
668
669 if (urb) {
670 if (netif_running (dev->net) &&
671 !test_bit (EVENT_RX_HALT, &dev->flags) &&
672 state != unlink_start) {
673 rx_submit (dev, urb, GFP_ATOMIC);
674 usb_mark_last_busy(dev->udev);
675 return;
676 }
677 usb_free_urb (urb);
678 }
679 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
680 }
681
682 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)683 void usbnet_pause_rx(struct usbnet *dev)
684 {
685 set_bit(EVENT_RX_PAUSED, &dev->flags);
686
687 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
688 }
689 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
690
usbnet_resume_rx(struct usbnet * dev)691 void usbnet_resume_rx(struct usbnet *dev)
692 {
693 struct sk_buff *skb;
694 int num = 0;
695
696 clear_bit(EVENT_RX_PAUSED, &dev->flags);
697
698 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
699 usbnet_skb_return(dev, skb);
700 num++;
701 }
702
703 tasklet_schedule(&dev->bh);
704
705 netif_dbg(dev, rx_status, dev->net,
706 "paused rx queue disabled, %d skbs requeued\n", num);
707 }
708 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
709
usbnet_purge_paused_rxq(struct usbnet * dev)710 void usbnet_purge_paused_rxq(struct usbnet *dev)
711 {
712 skb_queue_purge(&dev->rxq_pause);
713 }
714 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
715
716 /*-------------------------------------------------------------------------*/
717
718 // unlink pending rx/tx; completion handlers do all other cleanup
719
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)720 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
721 {
722 unsigned long flags;
723 struct sk_buff *skb;
724 int count = 0;
725
726 spin_lock_irqsave (&q->lock, flags);
727 while (!skb_queue_empty(q)) {
728 struct skb_data *entry;
729 struct urb *urb;
730 int retval;
731
732 skb_queue_walk(q, skb) {
733 entry = (struct skb_data *) skb->cb;
734 if (entry->state != unlink_start)
735 goto found;
736 }
737 break;
738 found:
739 entry->state = unlink_start;
740 urb = entry->urb;
741
742 /*
743 * Get reference count of the URB to avoid it to be
744 * freed during usb_unlink_urb, which may trigger
745 * use-after-free problem inside usb_unlink_urb since
746 * usb_unlink_urb is always racing with .complete
747 * handler(include defer_bh).
748 */
749 usb_get_urb(urb);
750 spin_unlock_irqrestore(&q->lock, flags);
751 // during some PM-driven resume scenarios,
752 // these (async) unlinks complete immediately
753 retval = usb_unlink_urb (urb);
754 if (retval != -EINPROGRESS && retval != 0)
755 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
756 else
757 count++;
758 usb_put_urb(urb);
759 spin_lock_irqsave(&q->lock, flags);
760 }
761 spin_unlock_irqrestore (&q->lock, flags);
762 return count;
763 }
764
765 // Flush all pending rx urbs
766 // minidrivers may need to do this when the MTU changes
767
usbnet_unlink_rx_urbs(struct usbnet * dev)768 void usbnet_unlink_rx_urbs(struct usbnet *dev)
769 {
770 if (netif_running(dev->net)) {
771 (void) unlink_urbs (dev, &dev->rxq);
772 tasklet_schedule(&dev->bh);
773 }
774 }
775 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
776
777 /*-------------------------------------------------------------------------*/
778
wait_skb_queue_empty(struct sk_buff_head * q)779 static void wait_skb_queue_empty(struct sk_buff_head *q)
780 {
781 unsigned long flags;
782
783 spin_lock_irqsave(&q->lock, flags);
784 while (!skb_queue_empty(q)) {
785 spin_unlock_irqrestore(&q->lock, flags);
786 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
787 set_current_state(TASK_UNINTERRUPTIBLE);
788 spin_lock_irqsave(&q->lock, flags);
789 }
790 spin_unlock_irqrestore(&q->lock, flags);
791 }
792
793 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)794 static void usbnet_terminate_urbs(struct usbnet *dev)
795 {
796 DECLARE_WAITQUEUE(wait, current);
797 int temp;
798
799 /* ensure there are no more active urbs */
800 add_wait_queue(&dev->wait, &wait);
801 set_current_state(TASK_UNINTERRUPTIBLE);
802 temp = unlink_urbs(dev, &dev->txq) +
803 unlink_urbs(dev, &dev->rxq);
804
805 /* maybe wait for deletions to finish. */
806 wait_skb_queue_empty(&dev->rxq);
807 wait_skb_queue_empty(&dev->txq);
808 wait_skb_queue_empty(&dev->done);
809 netif_dbg(dev, ifdown, dev->net,
810 "waited for %d urb completions\n", temp);
811 set_current_state(TASK_RUNNING);
812 remove_wait_queue(&dev->wait, &wait);
813 }
814
usbnet_stop(struct net_device * net)815 int usbnet_stop (struct net_device *net)
816 {
817 struct usbnet *dev = netdev_priv(net);
818 const struct driver_info *info = dev->driver_info;
819 int retval, pm, mpn;
820
821 clear_bit(EVENT_DEV_OPEN, &dev->flags);
822 netif_stop_queue (net);
823
824 netif_info(dev, ifdown, dev->net,
825 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
826 net->stats.rx_packets, net->stats.tx_packets,
827 net->stats.rx_errors, net->stats.tx_errors);
828
829 /* to not race resume */
830 pm = usb_autopm_get_interface(dev->intf);
831 /* allow minidriver to stop correctly (wireless devices to turn off
832 * radio etc) */
833 if (info->stop) {
834 retval = info->stop(dev);
835 if (retval < 0)
836 netif_info(dev, ifdown, dev->net,
837 "stop fail (%d) usbnet usb-%s-%s, %s\n",
838 retval,
839 dev->udev->bus->bus_name, dev->udev->devpath,
840 info->description);
841 }
842
843 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
844 usbnet_terminate_urbs(dev);
845
846 usbnet_status_stop(dev);
847
848 usbnet_purge_paused_rxq(dev);
849
850 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
851
852 /* deferred work (task, timer, softirq) must also stop.
853 * can't flush_scheduled_work() until we drop rtnl (later),
854 * else workers could deadlock; so make workers a NOP.
855 */
856 dev->flags = 0;
857 del_timer_sync (&dev->delay);
858 tasklet_kill (&dev->bh);
859 if (!pm)
860 usb_autopm_put_interface(dev->intf);
861
862 if (info->manage_power && mpn)
863 info->manage_power(dev, 0);
864 else
865 usb_autopm_put_interface(dev->intf);
866
867 return 0;
868 }
869 EXPORT_SYMBOL_GPL(usbnet_stop);
870
871 /*-------------------------------------------------------------------------*/
872
873 // posts reads, and enables write queuing
874
875 // precondition: never called in_interrupt
876
usbnet_open(struct net_device * net)877 int usbnet_open (struct net_device *net)
878 {
879 struct usbnet *dev = netdev_priv(net);
880 int retval;
881 const struct driver_info *info = dev->driver_info;
882
883 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
884 netif_info(dev, ifup, dev->net,
885 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
886 retval,
887 dev->udev->bus->bus_name,
888 dev->udev->devpath,
889 info->description);
890 goto done_nopm;
891 }
892
893 // put into "known safe" state
894 if (info->reset && (retval = info->reset (dev)) < 0) {
895 netif_info(dev, ifup, dev->net,
896 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
897 retval,
898 dev->udev->bus->bus_name,
899 dev->udev->devpath,
900 info->description);
901 goto done;
902 }
903
904 /* hard_mtu or rx_urb_size may change in reset() */
905 usbnet_update_max_qlen(dev);
906
907 // insist peer be connected
908 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
909 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
910 goto done;
911 }
912
913 /* start any status interrupt transfer */
914 if (dev->interrupt) {
915 retval = usbnet_status_start(dev, GFP_KERNEL);
916 if (retval < 0) {
917 netif_err(dev, ifup, dev->net,
918 "intr submit %d\n", retval);
919 goto done;
920 }
921 }
922
923 set_bit(EVENT_DEV_OPEN, &dev->flags);
924 netif_start_queue (net);
925 netif_info(dev, ifup, dev->net,
926 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
927 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
928 dev->net->mtu,
929 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
930 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
931 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
932 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
933 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
934 "simple");
935
936 /* reset rx error state */
937 dev->pkt_cnt = 0;
938 dev->pkt_err = 0;
939 clear_bit(EVENT_RX_KILL, &dev->flags);
940
941 // delay posting reads until we're fully open
942 tasklet_schedule (&dev->bh);
943 if (info->manage_power) {
944 retval = info->manage_power(dev, 1);
945 if (retval < 0) {
946 retval = 0;
947 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
948 } else {
949 usb_autopm_put_interface(dev->intf);
950 }
951 }
952 return retval;
953 done:
954 usb_autopm_put_interface(dev->intf);
955 done_nopm:
956 return retval;
957 }
958 EXPORT_SYMBOL_GPL(usbnet_open);
959
960 /*-------------------------------------------------------------------------*/
961
962 /* ethtool methods; minidrivers may need to add some more, but
963 * they'll probably want to use this base set.
964 */
965
966 /* These methods are written on the assumption that the device
967 * uses MII
968 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)969 int usbnet_get_link_ksettings_mii(struct net_device *net,
970 struct ethtool_link_ksettings *cmd)
971 {
972 struct usbnet *dev = netdev_priv(net);
973
974 if (!dev->mii.mdio_read)
975 return -EOPNOTSUPP;
976
977 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
978
979 return 0;
980 }
981 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
982
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)983 int usbnet_get_link_ksettings_internal(struct net_device *net,
984 struct ethtool_link_ksettings *cmd)
985 {
986 struct usbnet *dev = netdev_priv(net);
987
988 /* the assumption that speed is equal on tx and rx
989 * is deeply engrained into the networking layer.
990 * For wireless stuff it is not true.
991 * We assume that rx_speed matters more.
992 */
993 if (dev->rx_speed != SPEED_UNSET)
994 cmd->base.speed = dev->rx_speed / 1000000;
995 else if (dev->tx_speed != SPEED_UNSET)
996 cmd->base.speed = dev->tx_speed / 1000000;
997 else
998 cmd->base.speed = SPEED_UNKNOWN;
999
1000 return 0;
1001 }
1002 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1003
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1004 int usbnet_set_link_ksettings_mii(struct net_device *net,
1005 const struct ethtool_link_ksettings *cmd)
1006 {
1007 struct usbnet *dev = netdev_priv(net);
1008 int retval;
1009
1010 if (!dev->mii.mdio_write)
1011 return -EOPNOTSUPP;
1012
1013 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1014
1015 /* link speed/duplex might have changed */
1016 if (dev->driver_info->link_reset)
1017 dev->driver_info->link_reset(dev);
1018
1019 /* hard_mtu or rx_urb_size may change in link_reset() */
1020 usbnet_update_max_qlen(dev);
1021
1022 return retval;
1023 }
1024 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1025
usbnet_get_link(struct net_device * net)1026 u32 usbnet_get_link (struct net_device *net)
1027 {
1028 struct usbnet *dev = netdev_priv(net);
1029
1030 /* If a check_connect is defined, return its result */
1031 if (dev->driver_info->check_connect)
1032 return dev->driver_info->check_connect (dev) == 0;
1033
1034 /* if the device has mii operations, use those */
1035 if (dev->mii.mdio_read)
1036 return mii_link_ok(&dev->mii);
1037
1038 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1039 return ethtool_op_get_link(net);
1040 }
1041 EXPORT_SYMBOL_GPL(usbnet_get_link);
1042
usbnet_nway_reset(struct net_device * net)1043 int usbnet_nway_reset(struct net_device *net)
1044 {
1045 struct usbnet *dev = netdev_priv(net);
1046
1047 if (!dev->mii.mdio_write)
1048 return -EOPNOTSUPP;
1049
1050 return mii_nway_restart(&dev->mii);
1051 }
1052 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1053
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1054 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1055 {
1056 struct usbnet *dev = netdev_priv(net);
1057
1058 strlcpy (info->driver, dev->driver_name, sizeof info->driver);
1059 strlcpy (info->fw_version, dev->driver_info->description,
1060 sizeof info->fw_version);
1061 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1062 }
1063 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1064
usbnet_get_msglevel(struct net_device * net)1065 u32 usbnet_get_msglevel (struct net_device *net)
1066 {
1067 struct usbnet *dev = netdev_priv(net);
1068
1069 return dev->msg_enable;
1070 }
1071 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1072
usbnet_set_msglevel(struct net_device * net,u32 level)1073 void usbnet_set_msglevel (struct net_device *net, u32 level)
1074 {
1075 struct usbnet *dev = netdev_priv(net);
1076
1077 dev->msg_enable = level;
1078 }
1079 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1080
1081 /* drivers may override default ethtool_ops in their bind() routine */
1082 static const struct ethtool_ops usbnet_ethtool_ops = {
1083 .get_link = usbnet_get_link,
1084 .nway_reset = usbnet_nway_reset,
1085 .get_drvinfo = usbnet_get_drvinfo,
1086 .get_msglevel = usbnet_get_msglevel,
1087 .set_msglevel = usbnet_set_msglevel,
1088 .get_ts_info = ethtool_op_get_ts_info,
1089 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1090 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1091 };
1092
1093 /*-------------------------------------------------------------------------*/
1094
__handle_link_change(struct usbnet * dev)1095 static void __handle_link_change(struct usbnet *dev)
1096 {
1097 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1098 return;
1099
1100 if (!netif_carrier_ok(dev->net)) {
1101 /* kill URBs for reading packets to save bus bandwidth */
1102 unlink_urbs(dev, &dev->rxq);
1103
1104 /*
1105 * tx_timeout will unlink URBs for sending packets and
1106 * tx queue is stopped by netcore after link becomes off
1107 */
1108 } else {
1109 /* submitting URBs for reading packets */
1110 tasklet_schedule(&dev->bh);
1111 }
1112
1113 /* hard_mtu or rx_urb_size may change during link change */
1114 usbnet_update_max_qlen(dev);
1115
1116 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1117 }
1118
usbnet_set_rx_mode(struct net_device * net)1119 void usbnet_set_rx_mode(struct net_device *net)
1120 {
1121 struct usbnet *dev = netdev_priv(net);
1122
1123 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1124 }
1125 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1126
__handle_set_rx_mode(struct usbnet * dev)1127 static void __handle_set_rx_mode(struct usbnet *dev)
1128 {
1129 if (dev->driver_info->set_rx_mode)
1130 (dev->driver_info->set_rx_mode)(dev);
1131
1132 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1133 }
1134
1135 /* work that cannot be done in interrupt context uses keventd.
1136 *
1137 * NOTE: with 2.5 we could do more of this using completion callbacks,
1138 * especially now that control transfers can be queued.
1139 */
1140 static void
usbnet_deferred_kevent(struct work_struct * work)1141 usbnet_deferred_kevent (struct work_struct *work)
1142 {
1143 struct usbnet *dev =
1144 container_of(work, struct usbnet, kevent);
1145 int status;
1146
1147 /* usb_clear_halt() needs a thread context */
1148 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1149 unlink_urbs (dev, &dev->txq);
1150 status = usb_autopm_get_interface(dev->intf);
1151 if (status < 0)
1152 goto fail_pipe;
1153 status = usb_clear_halt (dev->udev, dev->out);
1154 usb_autopm_put_interface(dev->intf);
1155 if (status < 0 &&
1156 status != -EPIPE &&
1157 status != -ESHUTDOWN) {
1158 if (netif_msg_tx_err (dev))
1159 fail_pipe:
1160 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1161 status);
1162 } else {
1163 clear_bit (EVENT_TX_HALT, &dev->flags);
1164 if (status != -ESHUTDOWN)
1165 netif_wake_queue (dev->net);
1166 }
1167 }
1168 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1169 unlink_urbs (dev, &dev->rxq);
1170 status = usb_autopm_get_interface(dev->intf);
1171 if (status < 0)
1172 goto fail_halt;
1173 status = usb_clear_halt (dev->udev, dev->in);
1174 usb_autopm_put_interface(dev->intf);
1175 if (status < 0 &&
1176 status != -EPIPE &&
1177 status != -ESHUTDOWN) {
1178 if (netif_msg_rx_err (dev))
1179 fail_halt:
1180 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1181 status);
1182 } else {
1183 clear_bit (EVENT_RX_HALT, &dev->flags);
1184 tasklet_schedule (&dev->bh);
1185 }
1186 }
1187
1188 /* tasklet could resubmit itself forever if memory is tight */
1189 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1190 struct urb *urb = NULL;
1191 int resched = 1;
1192
1193 if (netif_running (dev->net))
1194 urb = usb_alloc_urb (0, GFP_KERNEL);
1195 else
1196 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1197 if (urb != NULL) {
1198 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1199 status = usb_autopm_get_interface(dev->intf);
1200 if (status < 0) {
1201 usb_free_urb(urb);
1202 goto fail_lowmem;
1203 }
1204 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1205 resched = 0;
1206 usb_autopm_put_interface(dev->intf);
1207 fail_lowmem:
1208 if (resched)
1209 tasklet_schedule (&dev->bh);
1210 }
1211 }
1212
1213 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1214 const struct driver_info *info = dev->driver_info;
1215 int retval = 0;
1216
1217 clear_bit (EVENT_LINK_RESET, &dev->flags);
1218 status = usb_autopm_get_interface(dev->intf);
1219 if (status < 0)
1220 goto skip_reset;
1221 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1222 usb_autopm_put_interface(dev->intf);
1223 skip_reset:
1224 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1225 retval,
1226 dev->udev->bus->bus_name,
1227 dev->udev->devpath,
1228 info->description);
1229 } else {
1230 usb_autopm_put_interface(dev->intf);
1231 }
1232
1233 /* handle link change from link resetting */
1234 __handle_link_change(dev);
1235 }
1236
1237 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1238 __handle_link_change(dev);
1239
1240 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1241 __handle_set_rx_mode(dev);
1242
1243
1244 if (dev->flags)
1245 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1246 }
1247
1248 /*-------------------------------------------------------------------------*/
1249
tx_complete(struct urb * urb)1250 static void tx_complete (struct urb *urb)
1251 {
1252 struct sk_buff *skb = (struct sk_buff *) urb->context;
1253 struct skb_data *entry = (struct skb_data *) skb->cb;
1254 struct usbnet *dev = entry->dev;
1255
1256 if (urb->status == 0) {
1257 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1258 unsigned long flags;
1259
1260 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1261 stats64->tx_packets += entry->packets;
1262 stats64->tx_bytes += entry->length;
1263 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1264 } else {
1265 dev->net->stats.tx_errors++;
1266
1267 switch (urb->status) {
1268 case -EPIPE:
1269 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1270 break;
1271
1272 /* software-driven interface shutdown */
1273 case -ECONNRESET: // async unlink
1274 case -ESHUTDOWN: // hardware gone
1275 break;
1276
1277 /* like rx, tx gets controller i/o faults during hub_wq
1278 * delays and so it uses the same throttling mechanism.
1279 */
1280 case -EPROTO:
1281 case -ETIME:
1282 case -EILSEQ:
1283 usb_mark_last_busy(dev->udev);
1284 if (!timer_pending (&dev->delay)) {
1285 mod_timer (&dev->delay,
1286 jiffies + THROTTLE_JIFFIES);
1287 netif_dbg(dev, link, dev->net,
1288 "tx throttle %d\n", urb->status);
1289 }
1290 netif_stop_queue (dev->net);
1291 break;
1292 default:
1293 netif_dbg(dev, tx_err, dev->net,
1294 "tx err %d\n", entry->urb->status);
1295 break;
1296 }
1297 }
1298
1299 usb_autopm_put_interface_async(dev->intf);
1300 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1301 }
1302
1303 /*-------------------------------------------------------------------------*/
1304
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1305 void usbnet_tx_timeout (struct net_device *net, unsigned int txqueue)
1306 {
1307 struct usbnet *dev = netdev_priv(net);
1308
1309 unlink_urbs (dev, &dev->txq);
1310 tasklet_schedule (&dev->bh);
1311 /* this needs to be handled individually because the generic layer
1312 * doesn't know what is sufficient and could not restore private
1313 * information if a remedy of an unconditional reset were used.
1314 */
1315 if (dev->driver_info->recover)
1316 (dev->driver_info->recover)(dev);
1317 }
1318 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1319
1320 /*-------------------------------------------------------------------------*/
1321
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1322 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1323 {
1324 unsigned num_sgs, total_len = 0;
1325 int i, s = 0;
1326
1327 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1328 if (num_sgs == 1)
1329 return 0;
1330
1331 /* reserve one for zero packet */
1332 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1333 GFP_ATOMIC);
1334 if (!urb->sg)
1335 return -ENOMEM;
1336
1337 urb->num_sgs = num_sgs;
1338 sg_init_table(urb->sg, urb->num_sgs + 1);
1339
1340 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1341 total_len += skb_headlen(skb);
1342
1343 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1344 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1345
1346 total_len += skb_frag_size(f);
1347 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1348 skb_frag_off(f));
1349 }
1350 urb->transfer_buffer_length = total_len;
1351
1352 return 1;
1353 }
1354
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1355 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1356 struct net_device *net)
1357 {
1358 struct usbnet *dev = netdev_priv(net);
1359 unsigned int length;
1360 struct urb *urb = NULL;
1361 struct skb_data *entry;
1362 const struct driver_info *info = dev->driver_info;
1363 unsigned long flags;
1364 int retval;
1365
1366 if (skb)
1367 skb_tx_timestamp(skb);
1368
1369 // some devices want funky USB-level framing, for
1370 // win32 driver (usually) and/or hardware quirks
1371 if (info->tx_fixup) {
1372 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1373 if (!skb) {
1374 /* packet collected; minidriver waiting for more */
1375 if (info->flags & FLAG_MULTI_PACKET)
1376 goto not_drop;
1377 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1378 goto drop;
1379 }
1380 }
1381
1382 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1383 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1384 goto drop;
1385 }
1386
1387 entry = (struct skb_data *) skb->cb;
1388 entry->urb = urb;
1389 entry->dev = dev;
1390
1391 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1392 skb->data, skb->len, tx_complete, skb);
1393 if (dev->can_dma_sg) {
1394 if (build_dma_sg(skb, urb) < 0)
1395 goto drop;
1396 }
1397 length = urb->transfer_buffer_length;
1398
1399 /* don't assume the hardware handles USB_ZERO_PACKET
1400 * NOTE: strictly conforming cdc-ether devices should expect
1401 * the ZLP here, but ignore the one-byte packet.
1402 * NOTE2: CDC NCM specification is different from CDC ECM when
1403 * handling ZLP/short packets, so cdc_ncm driver will make short
1404 * packet itself if needed.
1405 */
1406 if (length % dev->maxpacket == 0) {
1407 if (!(info->flags & FLAG_SEND_ZLP)) {
1408 if (!(info->flags & FLAG_MULTI_PACKET)) {
1409 length++;
1410 if (skb_tailroom(skb) && !urb->num_sgs) {
1411 skb->data[skb->len] = 0;
1412 __skb_put(skb, 1);
1413 } else if (urb->num_sgs)
1414 sg_set_buf(&urb->sg[urb->num_sgs++],
1415 dev->padding_pkt, 1);
1416 }
1417 } else
1418 urb->transfer_flags |= URB_ZERO_PACKET;
1419 }
1420 urb->transfer_buffer_length = length;
1421
1422 if (info->flags & FLAG_MULTI_PACKET) {
1423 /* Driver has set number of packets and a length delta.
1424 * Calculate the complete length and ensure that it's
1425 * positive.
1426 */
1427 entry->length += length;
1428 if (WARN_ON_ONCE(entry->length <= 0))
1429 entry->length = length;
1430 } else {
1431 usbnet_set_skb_tx_stats(skb, 1, length);
1432 }
1433
1434 spin_lock_irqsave(&dev->txq.lock, flags);
1435 retval = usb_autopm_get_interface_async(dev->intf);
1436 if (retval < 0) {
1437 spin_unlock_irqrestore(&dev->txq.lock, flags);
1438 goto drop;
1439 }
1440 if (netif_queue_stopped(net)) {
1441 usb_autopm_put_interface_async(dev->intf);
1442 spin_unlock_irqrestore(&dev->txq.lock, flags);
1443 goto drop;
1444 }
1445
1446 #ifdef CONFIG_PM
1447 /* if this triggers the device is still a sleep */
1448 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1449 /* transmission will be done in resume */
1450 usb_anchor_urb(urb, &dev->deferred);
1451 /* no use to process more packets */
1452 netif_stop_queue(net);
1453 usb_put_urb(urb);
1454 spin_unlock_irqrestore(&dev->txq.lock, flags);
1455 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1456 goto deferred;
1457 }
1458 #endif
1459
1460 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1461 case -EPIPE:
1462 netif_stop_queue (net);
1463 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1464 usb_autopm_put_interface_async(dev->intf);
1465 break;
1466 default:
1467 usb_autopm_put_interface_async(dev->intf);
1468 netif_dbg(dev, tx_err, dev->net,
1469 "tx: submit urb err %d\n", retval);
1470 break;
1471 case 0:
1472 netif_trans_update(net);
1473 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1474 if (dev->txq.qlen >= TX_QLEN (dev))
1475 netif_stop_queue (net);
1476 }
1477 spin_unlock_irqrestore (&dev->txq.lock, flags);
1478
1479 if (retval) {
1480 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1481 drop:
1482 dev->net->stats.tx_dropped++;
1483 not_drop:
1484 if (skb)
1485 dev_kfree_skb_any (skb);
1486 if (urb) {
1487 kfree(urb->sg);
1488 usb_free_urb(urb);
1489 }
1490 } else
1491 netif_dbg(dev, tx_queued, dev->net,
1492 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1493 #ifdef CONFIG_PM
1494 deferred:
1495 #endif
1496 return NETDEV_TX_OK;
1497 }
1498 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1499
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1500 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1501 {
1502 struct urb *urb;
1503 int i;
1504 int ret = 0;
1505
1506 /* don't refill the queue all at once */
1507 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1508 urb = usb_alloc_urb(0, flags);
1509 if (urb != NULL) {
1510 ret = rx_submit(dev, urb, flags);
1511 if (ret)
1512 goto err;
1513 } else {
1514 ret = -ENOMEM;
1515 goto err;
1516 }
1517 }
1518 err:
1519 return ret;
1520 }
1521
1522 /*-------------------------------------------------------------------------*/
1523
1524 // tasklet (work deferred from completions, in_irq) or timer
1525
usbnet_bh(struct timer_list * t)1526 static void usbnet_bh (struct timer_list *t)
1527 {
1528 struct usbnet *dev = from_timer(dev, t, delay);
1529 struct sk_buff *skb;
1530 struct skb_data *entry;
1531
1532 while ((skb = skb_dequeue (&dev->done))) {
1533 entry = (struct skb_data *) skb->cb;
1534 switch (entry->state) {
1535 case rx_done:
1536 entry->state = rx_cleanup;
1537 rx_process (dev, skb);
1538 continue;
1539 case tx_done:
1540 kfree(entry->urb->sg);
1541 fallthrough;
1542 case rx_cleanup:
1543 usb_free_urb (entry->urb);
1544 dev_kfree_skb (skb);
1545 continue;
1546 default:
1547 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1548 }
1549 }
1550
1551 /* restart RX again after disabling due to high error rate */
1552 clear_bit(EVENT_RX_KILL, &dev->flags);
1553
1554 /* waiting for all pending urbs to complete?
1555 * only then can we forgo submitting anew
1556 */
1557 if (waitqueue_active(&dev->wait)) {
1558 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1559 wake_up_all(&dev->wait);
1560
1561 // or are we maybe short a few urbs?
1562 } else if (netif_running (dev->net) &&
1563 netif_device_present (dev->net) &&
1564 netif_carrier_ok(dev->net) &&
1565 !timer_pending(&dev->delay) &&
1566 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1567 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1568 int temp = dev->rxq.qlen;
1569
1570 if (temp < RX_QLEN(dev)) {
1571 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1572 return;
1573 if (temp != dev->rxq.qlen)
1574 netif_dbg(dev, link, dev->net,
1575 "rxqlen %d --> %d\n",
1576 temp, dev->rxq.qlen);
1577 if (dev->rxq.qlen < RX_QLEN(dev))
1578 tasklet_schedule (&dev->bh);
1579 }
1580 if (dev->txq.qlen < TX_QLEN (dev))
1581 netif_wake_queue (dev->net);
1582 }
1583 }
1584
usbnet_bh_tasklet(struct tasklet_struct * t)1585 static void usbnet_bh_tasklet(struct tasklet_struct *t)
1586 {
1587 struct usbnet *dev = from_tasklet(dev, t, bh);
1588
1589 usbnet_bh(&dev->delay);
1590 }
1591
1592
1593 /*-------------------------------------------------------------------------
1594 *
1595 * USB Device Driver support
1596 *
1597 *-------------------------------------------------------------------------*/
1598
1599 // precondition: never called in_interrupt
1600
usbnet_disconnect(struct usb_interface * intf)1601 void usbnet_disconnect (struct usb_interface *intf)
1602 {
1603 struct usbnet *dev;
1604 struct usb_device *xdev;
1605 struct net_device *net;
1606
1607 dev = usb_get_intfdata(intf);
1608 usb_set_intfdata(intf, NULL);
1609 if (!dev)
1610 return;
1611
1612 xdev = interface_to_usbdev (intf);
1613
1614 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1615 intf->dev.driver->name,
1616 xdev->bus->bus_name, xdev->devpath,
1617 dev->driver_info->description);
1618
1619 if (dev->driver_info->unbind)
1620 dev->driver_info->unbind(dev, intf);
1621
1622 net = dev->net;
1623 unregister_netdev (net);
1624
1625 cancel_work_sync(&dev->kevent);
1626
1627 usb_scuttle_anchored_urbs(&dev->deferred);
1628
1629 usb_kill_urb(dev->interrupt);
1630 usb_free_urb(dev->interrupt);
1631 kfree(dev->padding_pkt);
1632
1633 free_percpu(net->tstats);
1634 free_netdev(net);
1635 }
1636 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1637
1638 static const struct net_device_ops usbnet_netdev_ops = {
1639 .ndo_open = usbnet_open,
1640 .ndo_stop = usbnet_stop,
1641 .ndo_start_xmit = usbnet_start_xmit,
1642 .ndo_tx_timeout = usbnet_tx_timeout,
1643 .ndo_set_rx_mode = usbnet_set_rx_mode,
1644 .ndo_change_mtu = usbnet_change_mtu,
1645 .ndo_get_stats64 = dev_get_tstats64,
1646 .ndo_set_mac_address = eth_mac_addr,
1647 .ndo_validate_addr = eth_validate_addr,
1648 };
1649
1650 /*-------------------------------------------------------------------------*/
1651
1652 // precondition: never called in_interrupt
1653
1654 static struct device_type wlan_type = {
1655 .name = "wlan",
1656 };
1657
1658 static struct device_type wwan_type = {
1659 .name = "wwan",
1660 };
1661
1662 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1663 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1664 {
1665 struct usbnet *dev;
1666 struct net_device *net;
1667 struct usb_host_interface *interface;
1668 const struct driver_info *info;
1669 struct usb_device *xdev;
1670 int status;
1671 const char *name;
1672 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1673
1674 /* usbnet already took usb runtime pm, so have to enable the feature
1675 * for usb interface, otherwise usb_autopm_get_interface may return
1676 * failure if RUNTIME_PM is enabled.
1677 */
1678 if (!driver->supports_autosuspend) {
1679 driver->supports_autosuspend = 1;
1680 pm_runtime_enable(&udev->dev);
1681 }
1682
1683 name = udev->dev.driver->name;
1684 info = (const struct driver_info *) prod->driver_info;
1685 if (!info) {
1686 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1687 return -ENODEV;
1688 }
1689 xdev = interface_to_usbdev (udev);
1690 interface = udev->cur_altsetting;
1691
1692 status = -ENOMEM;
1693
1694 // set up our own records
1695 net = alloc_etherdev(sizeof(*dev));
1696 if (!net)
1697 goto out;
1698
1699 /* netdev_printk() needs this so do it as early as possible */
1700 SET_NETDEV_DEV(net, &udev->dev);
1701
1702 dev = netdev_priv(net);
1703 dev->udev = xdev;
1704 dev->intf = udev;
1705 dev->driver_info = info;
1706 dev->driver_name = name;
1707 dev->rx_speed = SPEED_UNSET;
1708 dev->tx_speed = SPEED_UNSET;
1709
1710 net->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
1711 if (!net->tstats)
1712 goto out0;
1713
1714 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1715 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1716 init_waitqueue_head(&dev->wait);
1717 skb_queue_head_init (&dev->rxq);
1718 skb_queue_head_init (&dev->txq);
1719 skb_queue_head_init (&dev->done);
1720 skb_queue_head_init(&dev->rxq_pause);
1721 tasklet_setup(&dev->bh, usbnet_bh_tasklet);
1722 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1723 init_usb_anchor(&dev->deferred);
1724 timer_setup(&dev->delay, usbnet_bh, 0);
1725 mutex_init (&dev->phy_mutex);
1726 mutex_init(&dev->interrupt_mutex);
1727 dev->interrupt_count = 0;
1728
1729 dev->net = net;
1730 strscpy(net->name, "usb%d", sizeof(net->name));
1731 eth_hw_addr_set(net, node_id);
1732
1733 /* rx and tx sides can use different message sizes;
1734 * bind() should set rx_urb_size in that case.
1735 */
1736 dev->hard_mtu = net->mtu + net->hard_header_len;
1737 net->min_mtu = 0;
1738 net->max_mtu = ETH_MAX_MTU;
1739
1740 net->netdev_ops = &usbnet_netdev_ops;
1741 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1742 net->ethtool_ops = &usbnet_ethtool_ops;
1743
1744 // allow device-specific bind/init procedures
1745 // NOTE net->name still not usable ...
1746 if (info->bind) {
1747 status = info->bind (dev, udev);
1748 if (status < 0)
1749 goto out1;
1750
1751 // heuristic: "usb%d" for links we know are two-host,
1752 // else "eth%d" when there's reasonable doubt. userspace
1753 // can rename the link if it knows better.
1754 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1755 ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1756 (net->dev_addr [0] & 0x02) == 0))
1757 strscpy(net->name, "eth%d", sizeof(net->name));
1758 /* WLAN devices should always be named "wlan%d" */
1759 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1760 strscpy(net->name, "wlan%d", sizeof(net->name));
1761 /* WWAN devices should always be named "wwan%d" */
1762 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1763 strscpy(net->name, "wwan%d", sizeof(net->name));
1764
1765 /* devices that cannot do ARP */
1766 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1767 net->flags |= IFF_NOARP;
1768
1769 /* maybe the remote can't receive an Ethernet MTU */
1770 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1771 net->mtu = dev->hard_mtu - net->hard_header_len;
1772 } else if (!info->in || !info->out)
1773 status = usbnet_get_endpoints (dev, udev);
1774 else {
1775 dev->in = usb_rcvbulkpipe (xdev, info->in);
1776 dev->out = usb_sndbulkpipe (xdev, info->out);
1777 if (!(info->flags & FLAG_NO_SETINT))
1778 status = usb_set_interface (xdev,
1779 interface->desc.bInterfaceNumber,
1780 interface->desc.bAlternateSetting);
1781 else
1782 status = 0;
1783
1784 }
1785 if (status >= 0 && dev->status)
1786 status = init_status (dev, udev);
1787 if (status < 0)
1788 goto out3;
1789
1790 if (!dev->rx_urb_size)
1791 dev->rx_urb_size = dev->hard_mtu;
1792 dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1793 if (dev->maxpacket == 0) {
1794 /* that is a broken device */
1795 status = -ENODEV;
1796 goto out4;
1797 }
1798
1799 /* let userspace know we have a random address */
1800 if (ether_addr_equal(net->dev_addr, node_id))
1801 net->addr_assign_type = NET_ADDR_RANDOM;
1802
1803 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1804 SET_NETDEV_DEVTYPE(net, &wlan_type);
1805 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1806 SET_NETDEV_DEVTYPE(net, &wwan_type);
1807
1808 /* initialize max rx_qlen and tx_qlen */
1809 usbnet_update_max_qlen(dev);
1810
1811 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1812 !(info->flags & FLAG_MULTI_PACKET)) {
1813 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1814 if (!dev->padding_pkt) {
1815 status = -ENOMEM;
1816 goto out4;
1817 }
1818 }
1819
1820 status = register_netdev (net);
1821 if (status)
1822 goto out5;
1823 netif_info(dev, probe, dev->net,
1824 "register '%s' at usb-%s-%s, %s, %pM\n",
1825 udev->dev.driver->name,
1826 xdev->bus->bus_name, xdev->devpath,
1827 dev->driver_info->description,
1828 net->dev_addr);
1829
1830 // ok, it's ready to go.
1831 usb_set_intfdata (udev, dev);
1832
1833 netif_device_attach (net);
1834
1835 if (dev->driver_info->flags & FLAG_LINK_INTR)
1836 usbnet_link_change(dev, 0, 0);
1837
1838 return 0;
1839
1840 out5:
1841 kfree(dev->padding_pkt);
1842 out4:
1843 usb_free_urb(dev->interrupt);
1844 out3:
1845 if (info->unbind)
1846 info->unbind (dev, udev);
1847 out1:
1848 /* subdrivers must undo all they did in bind() if they
1849 * fail it, but we may fail later and a deferred kevent
1850 * may trigger an error resubmitting itself and, worse,
1851 * schedule a timer. So we kill it all just in case.
1852 */
1853 cancel_work_sync(&dev->kevent);
1854 del_timer_sync(&dev->delay);
1855 free_percpu(net->tstats);
1856 out0:
1857 free_netdev(net);
1858 out:
1859 return status;
1860 }
1861 EXPORT_SYMBOL_GPL(usbnet_probe);
1862
1863 /*-------------------------------------------------------------------------*/
1864
1865 /*
1866 * suspend the whole driver as soon as the first interface is suspended
1867 * resume only when the last interface is resumed
1868 */
1869
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1870 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1871 {
1872 struct usbnet *dev = usb_get_intfdata(intf);
1873
1874 if (!dev->suspend_count++) {
1875 spin_lock_irq(&dev->txq.lock);
1876 /* don't autosuspend while transmitting */
1877 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1878 dev->suspend_count--;
1879 spin_unlock_irq(&dev->txq.lock);
1880 return -EBUSY;
1881 } else {
1882 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1883 spin_unlock_irq(&dev->txq.lock);
1884 }
1885 /*
1886 * accelerate emptying of the rx and queues, to avoid
1887 * having everything error out.
1888 */
1889 netif_device_detach (dev->net);
1890 usbnet_terminate_urbs(dev);
1891 __usbnet_status_stop_force(dev);
1892
1893 /*
1894 * reattach so runtime management can use and
1895 * wake the device
1896 */
1897 netif_device_attach (dev->net);
1898 }
1899 return 0;
1900 }
1901 EXPORT_SYMBOL_GPL(usbnet_suspend);
1902
usbnet_resume(struct usb_interface * intf)1903 int usbnet_resume (struct usb_interface *intf)
1904 {
1905 struct usbnet *dev = usb_get_intfdata(intf);
1906 struct sk_buff *skb;
1907 struct urb *res;
1908 int retval;
1909
1910 if (!--dev->suspend_count) {
1911 /* resume interrupt URB if it was previously submitted */
1912 __usbnet_status_start_force(dev, GFP_NOIO);
1913
1914 spin_lock_irq(&dev->txq.lock);
1915 while ((res = usb_get_from_anchor(&dev->deferred))) {
1916
1917 skb = (struct sk_buff *)res->context;
1918 retval = usb_submit_urb(res, GFP_ATOMIC);
1919 if (retval < 0) {
1920 dev_kfree_skb_any(skb);
1921 kfree(res->sg);
1922 usb_free_urb(res);
1923 usb_autopm_put_interface_async(dev->intf);
1924 } else {
1925 netif_trans_update(dev->net);
1926 __skb_queue_tail(&dev->txq, skb);
1927 }
1928 }
1929
1930 smp_mb();
1931 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1932 spin_unlock_irq(&dev->txq.lock);
1933
1934 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1935 /* handle remote wakeup ASAP
1936 * we cannot race against stop
1937 */
1938 if (netif_device_present(dev->net) &&
1939 !timer_pending(&dev->delay) &&
1940 !test_bit(EVENT_RX_HALT, &dev->flags))
1941 rx_alloc_submit(dev, GFP_NOIO);
1942
1943 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1944 netif_tx_wake_all_queues(dev->net);
1945 tasklet_schedule (&dev->bh);
1946 }
1947 }
1948
1949 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1950 usb_autopm_get_interface_no_resume(intf);
1951
1952 return 0;
1953 }
1954 EXPORT_SYMBOL_GPL(usbnet_resume);
1955
1956 /*
1957 * Either a subdriver implements manage_power, then it is assumed to always
1958 * be ready to be suspended or it reports the readiness to be suspended
1959 * explicitly
1960 */
usbnet_device_suggests_idle(struct usbnet * dev)1961 void usbnet_device_suggests_idle(struct usbnet *dev)
1962 {
1963 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1964 dev->intf->needs_remote_wakeup = 1;
1965 usb_autopm_put_interface_async(dev->intf);
1966 }
1967 }
1968 EXPORT_SYMBOL(usbnet_device_suggests_idle);
1969
1970 /*
1971 * For devices that can do without special commands
1972 */
usbnet_manage_power(struct usbnet * dev,int on)1973 int usbnet_manage_power(struct usbnet *dev, int on)
1974 {
1975 dev->intf->needs_remote_wakeup = on;
1976 return 0;
1977 }
1978 EXPORT_SYMBOL(usbnet_manage_power);
1979
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)1980 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
1981 {
1982 /* update link after link is reseted */
1983 if (link && !need_reset)
1984 netif_carrier_on(dev->net);
1985 else
1986 netif_carrier_off(dev->net);
1987
1988 if (need_reset && link)
1989 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
1990 else
1991 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
1992 }
1993 EXPORT_SYMBOL(usbnet_link_change);
1994
1995 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)1996 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
1997 u16 value, u16 index, void *data, u16 size)
1998 {
1999 void *buf = NULL;
2000 int err = -ENOMEM;
2001
2002 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2003 " value=0x%04x index=0x%04x size=%d\n",
2004 cmd, reqtype, value, index, size);
2005
2006 if (size) {
2007 buf = kmalloc(size, GFP_KERNEL);
2008 if (!buf)
2009 goto out;
2010 }
2011
2012 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2013 cmd, reqtype, value, index, buf, size,
2014 USB_CTRL_GET_TIMEOUT);
2015 if (err > 0 && err <= size) {
2016 if (data)
2017 memcpy(data, buf, err);
2018 else
2019 netdev_dbg(dev->net,
2020 "Huh? Data requested but thrown away.\n");
2021 }
2022 kfree(buf);
2023 out:
2024 return err;
2025 }
2026
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2027 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2028 u16 value, u16 index, const void *data,
2029 u16 size)
2030 {
2031 void *buf = NULL;
2032 int err = -ENOMEM;
2033
2034 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2035 " value=0x%04x index=0x%04x size=%d\n",
2036 cmd, reqtype, value, index, size);
2037
2038 if (data) {
2039 buf = kmemdup(data, size, GFP_KERNEL);
2040 if (!buf)
2041 goto out;
2042 } else {
2043 if (size) {
2044 WARN_ON_ONCE(1);
2045 err = -EINVAL;
2046 goto out;
2047 }
2048 }
2049
2050 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2051 cmd, reqtype, value, index, buf, size,
2052 USB_CTRL_SET_TIMEOUT);
2053 kfree(buf);
2054
2055 out:
2056 return err;
2057 }
2058
2059 /*
2060 * The function can't be called inside suspend/resume callback,
2061 * otherwise deadlock will be caused.
2062 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2063 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2064 u16 value, u16 index, void *data, u16 size)
2065 {
2066 int ret;
2067
2068 if (usb_autopm_get_interface(dev->intf) < 0)
2069 return -ENODEV;
2070 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2071 data, size);
2072 usb_autopm_put_interface(dev->intf);
2073 return ret;
2074 }
2075 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2076
2077 /*
2078 * The function can't be called inside suspend/resume callback,
2079 * otherwise deadlock will be caused.
2080 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2081 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2082 u16 value, u16 index, const void *data, u16 size)
2083 {
2084 int ret;
2085
2086 if (usb_autopm_get_interface(dev->intf) < 0)
2087 return -ENODEV;
2088 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2089 data, size);
2090 usb_autopm_put_interface(dev->intf);
2091 return ret;
2092 }
2093 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2094
2095 /*
2096 * The function can be called inside suspend/resume callback safely
2097 * and should only be called by suspend/resume callback generally.
2098 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2099 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2100 u16 value, u16 index, void *data, u16 size)
2101 {
2102 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2103 data, size);
2104 }
2105 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2106
2107 /*
2108 * The function can be called inside suspend/resume callback safely
2109 * and should only be called by suspend/resume callback generally.
2110 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2111 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2112 u16 value, u16 index, const void *data,
2113 u16 size)
2114 {
2115 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2116 data, size);
2117 }
2118 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2119
usbnet_async_cmd_cb(struct urb * urb)2120 static void usbnet_async_cmd_cb(struct urb *urb)
2121 {
2122 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2123 int status = urb->status;
2124
2125 if (status < 0)
2126 dev_dbg(&urb->dev->dev, "%s failed with %d",
2127 __func__, status);
2128
2129 kfree(req);
2130 usb_free_urb(urb);
2131 }
2132
2133 /*
2134 * The caller must make sure that device can't be put into suspend
2135 * state until the control URB completes.
2136 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2137 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2138 u16 value, u16 index, const void *data, u16 size)
2139 {
2140 struct usb_ctrlrequest *req = NULL;
2141 struct urb *urb;
2142 int err = -ENOMEM;
2143 void *buf = NULL;
2144
2145 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2146 " value=0x%04x index=0x%04x size=%d\n",
2147 cmd, reqtype, value, index, size);
2148
2149 urb = usb_alloc_urb(0, GFP_ATOMIC);
2150 if (!urb)
2151 goto fail;
2152
2153 if (data) {
2154 buf = kmemdup(data, size, GFP_ATOMIC);
2155 if (!buf) {
2156 netdev_err(dev->net, "Error allocating buffer"
2157 " in %s!\n", __func__);
2158 goto fail_free;
2159 }
2160 }
2161
2162 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2163 if (!req)
2164 goto fail_free_buf;
2165
2166 req->bRequestType = reqtype;
2167 req->bRequest = cmd;
2168 req->wValue = cpu_to_le16(value);
2169 req->wIndex = cpu_to_le16(index);
2170 req->wLength = cpu_to_le16(size);
2171
2172 usb_fill_control_urb(urb, dev->udev,
2173 usb_sndctrlpipe(dev->udev, 0),
2174 (void *)req, buf, size,
2175 usbnet_async_cmd_cb, req);
2176 urb->transfer_flags |= URB_FREE_BUFFER;
2177
2178 err = usb_submit_urb(urb, GFP_ATOMIC);
2179 if (err < 0) {
2180 netdev_err(dev->net, "Error submitting the control"
2181 " message: status=%d\n", err);
2182 goto fail_free;
2183 }
2184 return 0;
2185
2186 fail_free_buf:
2187 kfree(buf);
2188 fail_free:
2189 kfree(req);
2190 usb_free_urb(urb);
2191 fail:
2192 return err;
2193
2194 }
2195 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2196 /*-------------------------------------------------------------------------*/
2197
usbnet_init(void)2198 static int __init usbnet_init(void)
2199 {
2200 /* Compiler should optimize this out. */
2201 BUILD_BUG_ON(
2202 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2203
2204 eth_random_addr(node_id);
2205 return 0;
2206 }
2207 module_init(usbnet_init);
2208
usbnet_exit(void)2209 static void __exit usbnet_exit(void)
2210 {
2211 }
2212 module_exit(usbnet_exit);
2213
2214 MODULE_AUTHOR("David Brownell");
2215 MODULE_DESCRIPTION("USB network driver framework");
2216 MODULE_LICENSE("GPL");
2217