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 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/ctype.h>
25 #include <linux/ethtool.h>
26 #include <linux/workqueue.h>
27 #include <linux/mii.h>
28 #include <linux/usb.h>
29 #include <linux/usb/usbnet.h>
30 #include <linux/slab.h>
31 #include <linux/kernel.h>
32 #include <linux/pm_runtime.h>
33
34 /*-------------------------------------------------------------------------*/
35
36 /*
37 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
38 * Several dozen bytes of IPv4 data can fit in two such transactions.
39 * One maximum size Ethernet packet takes twenty four of them.
40 * For high speed, each frame comfortably fits almost 36 max size
41 * Ethernet packets (so queues should be bigger).
42 *
43 * The goal is to let the USB host controller be busy for 5msec or
44 * more before an irq is required, under load. Jumbograms change
45 * the equation.
46 */
47 #define MAX_QUEUE_MEMORY (60 * 1518)
48 #define RX_QLEN(dev) ((dev)->rx_qlen)
49 #define TX_QLEN(dev) ((dev)->tx_qlen)
50
51 // reawaken network queue this soon after stopping; else watchdog barks
52 #define TX_TIMEOUT_JIFFIES (5*HZ)
53
54 /* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
55 * us (it polls at HZ/4 usually) before we report too many false errors.
56 */
57 #define THROTTLE_JIFFIES (HZ/8)
58
59 // between wakeups
60 #define UNLINK_TIMEOUT_MS 3
61
62 /*-------------------------------------------------------------------------*/
63
64 /* use ethtool to change the level for any given device */
65 static int msg_level = -1;
66 module_param (msg_level, int, 0);
67 MODULE_PARM_DESC (msg_level, "Override default message level");
68
69 /*-------------------------------------------------------------------------*/
70
71 static const char * const usbnet_event_names[] = {
72 [EVENT_TX_HALT] = "EVENT_TX_HALT",
73 [EVENT_RX_HALT] = "EVENT_RX_HALT",
74 [EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
75 [EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
76 [EVENT_LINK_RESET] = "EVENT_LINK_RESET",
77 [EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
78 [EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
79 [EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
80 [EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
81 [EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
82 [EVENT_RX_KILL] = "EVENT_RX_KILL",
83 [EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
84 [EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
85 [EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
86 };
87
88 /* handles CDC Ethernet and many other network "bulk data" interfaces */
usbnet_get_endpoints(struct usbnet * dev,struct usb_interface * intf)89 int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
90 {
91 int tmp;
92 struct usb_host_interface *alt = NULL;
93 struct usb_host_endpoint *in = NULL, *out = NULL;
94 struct usb_host_endpoint *status = NULL;
95
96 for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
97 unsigned ep;
98
99 in = out = status = NULL;
100 alt = intf->altsetting + tmp;
101
102 /* take the first altsetting with in-bulk + out-bulk;
103 * remember any status endpoint, just in case;
104 * ignore other endpoints and altsettings.
105 */
106 for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
107 struct usb_host_endpoint *e;
108 int intr = 0;
109
110 e = alt->endpoint + ep;
111
112 /* ignore endpoints which cannot transfer data */
113 if (!usb_endpoint_maxp(&e->desc))
114 continue;
115
116 switch (e->desc.bmAttributes) {
117 case USB_ENDPOINT_XFER_INT:
118 if (!usb_endpoint_dir_in(&e->desc))
119 continue;
120 intr = 1;
121 fallthrough;
122 case USB_ENDPOINT_XFER_BULK:
123 break;
124 default:
125 continue;
126 }
127 if (usb_endpoint_dir_in(&e->desc)) {
128 if (!intr && !in)
129 in = e;
130 else if (intr && !status)
131 status = e;
132 } else {
133 if (!out)
134 out = e;
135 }
136 }
137 if (in && out)
138 break;
139 }
140 if (!alt || !in || !out)
141 return -EINVAL;
142
143 if (alt->desc.bAlternateSetting != 0 ||
144 !(dev->driver_info->flags & FLAG_NO_SETINT)) {
145 tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
146 alt->desc.bAlternateSetting);
147 if (tmp < 0)
148 return tmp;
149 }
150
151 dev->in = usb_rcvbulkpipe (dev->udev,
152 in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
153 dev->out = usb_sndbulkpipe (dev->udev,
154 out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
155 dev->status = status;
156 return 0;
157 }
158 EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
159
usbnet_get_ethernet_addr(struct usbnet * dev,int iMACAddress)160 int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
161 {
162 u8 addr[ETH_ALEN];
163 int tmp = -1, ret;
164 unsigned char buf [13];
165
166 ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
167 if (ret == 12)
168 tmp = hex2bin(addr, buf, 6);
169 if (tmp < 0) {
170 dev_dbg(&dev->udev->dev,
171 "bad MAC string %d fetch, %d\n", iMACAddress, tmp);
172 if (ret >= 0)
173 ret = -EINVAL;
174 return ret;
175 }
176 eth_hw_addr_set(dev->net, addr);
177 return 0;
178 }
179 EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
180
usbnet_needs_usb_name_format(struct usbnet * dev,struct net_device * net)181 static bool usbnet_needs_usb_name_format(struct usbnet *dev, struct net_device *net)
182 {
183 /* Point to point devices which don't have a real MAC address
184 * (or report a fake local one) have historically used the usb%d
185 * naming. Preserve this..
186 */
187 return (dev->driver_info->flags & FLAG_POINTTOPOINT) != 0 &&
188 (is_zero_ether_addr(net->dev_addr) ||
189 is_local_ether_addr(net->dev_addr));
190 }
191
intr_complete(struct urb * urb)192 static void intr_complete (struct urb *urb)
193 {
194 struct usbnet *dev = urb->context;
195 int status = urb->status;
196
197 switch (status) {
198 /* success */
199 case 0:
200 dev->driver_info->status(dev, urb);
201 break;
202
203 /* software-driven interface shutdown */
204 case -ENOENT: /* urb killed */
205 case -ESHUTDOWN: /* hardware gone */
206 netif_dbg(dev, ifdown, dev->net,
207 "intr shutdown, code %d\n", status);
208 return;
209
210 /* NOTE: not throttling like RX/TX, since this endpoint
211 * already polls infrequently
212 */
213 default:
214 netdev_dbg(dev->net, "intr status %d\n", status);
215 break;
216 }
217
218 status = usb_submit_urb (urb, GFP_ATOMIC);
219 if (status != 0)
220 netif_err(dev, timer, dev->net,
221 "intr resubmit --> %d\n", status);
222 }
223
init_status(struct usbnet * dev,struct usb_interface * intf)224 static int init_status (struct usbnet *dev, struct usb_interface *intf)
225 {
226 char *buf = NULL;
227 unsigned pipe = 0;
228 unsigned maxp;
229 unsigned period;
230
231 if (!dev->driver_info->status)
232 return 0;
233
234 pipe = usb_rcvintpipe (dev->udev,
235 dev->status->desc.bEndpointAddress
236 & USB_ENDPOINT_NUMBER_MASK);
237 maxp = usb_maxpacket(dev->udev, pipe);
238
239 /* avoid 1 msec chatter: min 8 msec poll rate */
240 period = max ((int) dev->status->desc.bInterval,
241 (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
242
243 buf = kmalloc (maxp, GFP_KERNEL);
244 if (buf) {
245 dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
246 if (!dev->interrupt) {
247 kfree (buf);
248 return -ENOMEM;
249 } else {
250 usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
251 buf, maxp, intr_complete, dev, period);
252 dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
253 dev_dbg(&intf->dev,
254 "status ep%din, %d bytes period %d\n",
255 usb_pipeendpoint(pipe), maxp, period);
256 }
257 }
258 return 0;
259 }
260
261 /* Submit the interrupt URB if not previously submitted, increasing refcount */
usbnet_status_start(struct usbnet * dev,gfp_t mem_flags)262 int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
263 {
264 int ret = 0;
265
266 WARN_ON_ONCE(dev->interrupt == NULL);
267 if (dev->interrupt) {
268 mutex_lock(&dev->interrupt_mutex);
269
270 if (++dev->interrupt_count == 1)
271 ret = usb_submit_urb(dev->interrupt, mem_flags);
272
273 dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
274 dev->interrupt_count);
275 mutex_unlock(&dev->interrupt_mutex);
276 }
277 return ret;
278 }
279 EXPORT_SYMBOL_GPL(usbnet_status_start);
280
281 /* For resume; submit interrupt URB if previously submitted */
__usbnet_status_start_force(struct usbnet * dev,gfp_t mem_flags)282 static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
283 {
284 int ret = 0;
285
286 mutex_lock(&dev->interrupt_mutex);
287 if (dev->interrupt_count) {
288 ret = usb_submit_urb(dev->interrupt, mem_flags);
289 dev_dbg(&dev->udev->dev,
290 "submitted interrupt URB for resume\n");
291 }
292 mutex_unlock(&dev->interrupt_mutex);
293 return ret;
294 }
295
296 /* Kill the interrupt URB if all submitters want it killed */
usbnet_status_stop(struct usbnet * dev)297 void usbnet_status_stop(struct usbnet *dev)
298 {
299 if (dev->interrupt) {
300 mutex_lock(&dev->interrupt_mutex);
301 WARN_ON(dev->interrupt_count == 0);
302
303 if (dev->interrupt_count && --dev->interrupt_count == 0)
304 usb_kill_urb(dev->interrupt);
305
306 dev_dbg(&dev->udev->dev,
307 "decremented interrupt URB count to %d\n",
308 dev->interrupt_count);
309 mutex_unlock(&dev->interrupt_mutex);
310 }
311 }
312 EXPORT_SYMBOL_GPL(usbnet_status_stop);
313
314 /* For suspend; always kill interrupt URB */
__usbnet_status_stop_force(struct usbnet * dev)315 static void __usbnet_status_stop_force(struct usbnet *dev)
316 {
317 if (dev->interrupt) {
318 mutex_lock(&dev->interrupt_mutex);
319 usb_kill_urb(dev->interrupt);
320 dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
321 mutex_unlock(&dev->interrupt_mutex);
322 }
323 }
324
325 /* Passes this packet up the stack, updating its accounting.
326 * Some link protocols batch packets, so their rx_fixup paths
327 * can return clones as well as just modify the original skb.
328 */
usbnet_skb_return(struct usbnet * dev,struct sk_buff * skb)329 void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
330 {
331 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
332 unsigned long flags;
333 int status;
334
335 if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
336 skb_queue_tail(&dev->rxq_pause, skb);
337 return;
338 }
339
340 /* only update if unset to allow minidriver rx_fixup override */
341 if (skb->protocol == 0)
342 skb->protocol = eth_type_trans (skb, dev->net);
343
344 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
345 u64_stats_inc(&stats64->rx_packets);
346 u64_stats_add(&stats64->rx_bytes, skb->len);
347 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
348
349 netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
350 skb->len + sizeof (struct ethhdr), skb->protocol);
351 memset (skb->cb, 0, sizeof (struct skb_data));
352
353 if (skb_defer_rx_timestamp(skb))
354 return;
355
356 status = netif_rx (skb);
357 if (status != NET_RX_SUCCESS)
358 netif_dbg(dev, rx_err, dev->net,
359 "netif_rx status %d\n", status);
360 }
361 EXPORT_SYMBOL_GPL(usbnet_skb_return);
362
363 /* must be called if hard_mtu or rx_urb_size changed */
usbnet_update_max_qlen(struct usbnet * dev)364 void usbnet_update_max_qlen(struct usbnet *dev)
365 {
366 enum usb_device_speed speed = dev->udev->speed;
367
368 if (!dev->rx_urb_size || !dev->hard_mtu)
369 goto insanity;
370 switch (speed) {
371 case USB_SPEED_HIGH:
372 dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
373 dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
374 break;
375 case USB_SPEED_SUPER:
376 case USB_SPEED_SUPER_PLUS:
377 /*
378 * Not take default 5ms qlen for super speed HC to
379 * save memory, and iperf tests show 2.5ms qlen can
380 * work well
381 */
382 dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
383 dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
384 break;
385 default:
386 insanity:
387 dev->rx_qlen = dev->tx_qlen = 4;
388 }
389 }
390 EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
391
392
393 /*-------------------------------------------------------------------------
394 *
395 * Network Device Driver (peer link to "Host Device", from USB host)
396 *
397 *-------------------------------------------------------------------------*/
398
usbnet_change_mtu(struct net_device * net,int new_mtu)399 int usbnet_change_mtu (struct net_device *net, int new_mtu)
400 {
401 struct usbnet *dev = netdev_priv(net);
402 int ll_mtu = new_mtu + net->hard_header_len;
403 int old_hard_mtu = dev->hard_mtu;
404 int old_rx_urb_size = dev->rx_urb_size;
405
406 // no second zero-length packet read wanted after mtu-sized packets
407 if ((ll_mtu % dev->maxpacket) == 0)
408 return -EDOM;
409 WRITE_ONCE(net->mtu, new_mtu);
410
411 dev->hard_mtu = net->mtu + net->hard_header_len;
412 if (dev->rx_urb_size == old_hard_mtu) {
413 dev->rx_urb_size = dev->hard_mtu;
414 if (dev->rx_urb_size > old_rx_urb_size) {
415 usbnet_pause_rx(dev);
416 usbnet_unlink_rx_urbs(dev);
417 usbnet_resume_rx(dev);
418 }
419 }
420
421 /* max qlen depend on hard_mtu and rx_urb_size */
422 usbnet_update_max_qlen(dev);
423
424 return 0;
425 }
426 EXPORT_SYMBOL_GPL(usbnet_change_mtu);
427
428 /* The caller must hold list->lock */
__usbnet_queue_skb(struct sk_buff_head * list,struct sk_buff * newsk,enum skb_state state)429 static void __usbnet_queue_skb(struct sk_buff_head *list,
430 struct sk_buff *newsk, enum skb_state state)
431 {
432 struct skb_data *entry = (struct skb_data *) newsk->cb;
433
434 __skb_queue_tail(list, newsk);
435 entry->state = state;
436 }
437
438 /*-------------------------------------------------------------------------*/
439
440 /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
441 * completion callbacks. 2.5 should have fixed those bugs...
442 */
443
defer_bh(struct usbnet * dev,struct sk_buff * skb,struct sk_buff_head * list,enum skb_state state)444 static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
445 struct sk_buff_head *list, enum skb_state state)
446 {
447 unsigned long flags;
448 enum skb_state old_state;
449 struct skb_data *entry = (struct skb_data *) skb->cb;
450
451 spin_lock_irqsave(&list->lock, flags);
452 old_state = entry->state;
453 entry->state = state;
454 __skb_unlink(skb, list);
455
456 /* defer_bh() is never called with list == &dev->done.
457 * spin_lock_nested() tells lockdep that it is OK to take
458 * dev->done.lock here with list->lock held.
459 */
460 spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
461
462 __skb_queue_tail(&dev->done, skb);
463 if (dev->done.qlen == 1)
464 tasklet_schedule(&dev->bh);
465 spin_unlock(&dev->done.lock);
466 spin_unlock_irqrestore(&list->lock, flags);
467 return old_state;
468 }
469
470 /* some work can't be done in tasklets, so we use keventd
471 *
472 * NOTE: annoying asymmetry: if it's active, schedule_work() fails,
473 * but tasklet_schedule() doesn't. hope the failure is rare.
474 */
usbnet_defer_kevent(struct usbnet * dev,int work)475 void usbnet_defer_kevent (struct usbnet *dev, int work)
476 {
477 set_bit (work, &dev->flags);
478 if (!usbnet_going_away(dev)) {
479 if (!schedule_work(&dev->kevent))
480 netdev_dbg(dev->net,
481 "kevent %s may have been dropped\n",
482 usbnet_event_names[work]);
483 else
484 netdev_dbg(dev->net,
485 "kevent %s scheduled\n", usbnet_event_names[work]);
486 }
487 }
488 EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
489
490 /*-------------------------------------------------------------------------*/
491
492 static void rx_complete (struct urb *urb);
493
rx_submit(struct usbnet * dev,struct urb * urb,gfp_t flags)494 static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
495 {
496 struct sk_buff *skb;
497 struct skb_data *entry;
498 int retval = 0;
499 unsigned long lockflags;
500 size_t size = dev->rx_urb_size;
501
502 /* prevent rx skb allocation when error ratio is high */
503 if (test_bit(EVENT_RX_KILL, &dev->flags)) {
504 usb_free_urb(urb);
505 return -ENOLINK;
506 }
507
508 if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
509 skb = __netdev_alloc_skb(dev->net, size, flags);
510 else
511 skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
512 if (!skb) {
513 netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
514 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
515 usb_free_urb (urb);
516 return -ENOMEM;
517 }
518
519 entry = (struct skb_data *) skb->cb;
520 entry->urb = urb;
521 entry->dev = dev;
522 entry->length = 0;
523
524 usb_fill_bulk_urb (urb, dev->udev, dev->in,
525 skb->data, size, rx_complete, skb);
526
527 spin_lock_irqsave (&dev->rxq.lock, lockflags);
528
529 if (netif_running (dev->net) &&
530 netif_device_present (dev->net) &&
531 test_bit(EVENT_DEV_OPEN, &dev->flags) &&
532 !test_bit (EVENT_RX_HALT, &dev->flags) &&
533 !test_bit (EVENT_DEV_ASLEEP, &dev->flags) &&
534 !usbnet_going_away(dev)) {
535 switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
536 case -EPIPE:
537 usbnet_defer_kevent (dev, EVENT_RX_HALT);
538 break;
539 case -ENOMEM:
540 usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
541 break;
542 case -ENODEV:
543 netif_dbg(dev, ifdown, dev->net, "device gone\n");
544 netif_device_detach (dev->net);
545 break;
546 case -EHOSTUNREACH:
547 retval = -ENOLINK;
548 break;
549 default:
550 netif_dbg(dev, rx_err, dev->net,
551 "rx submit, %d\n", retval);
552 tasklet_schedule (&dev->bh);
553 break;
554 case 0:
555 __usbnet_queue_skb(&dev->rxq, skb, rx_start);
556 }
557 } else {
558 netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
559 retval = -ENOLINK;
560 }
561 spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
562 if (retval) {
563 dev_kfree_skb_any (skb);
564 usb_free_urb (urb);
565 }
566 return retval;
567 }
568
569
570 /*-------------------------------------------------------------------------*/
571
rx_process(struct usbnet * dev,struct sk_buff * skb)572 static inline int rx_process(struct usbnet *dev, struct sk_buff *skb)
573 {
574 if (dev->driver_info->rx_fixup &&
575 !dev->driver_info->rx_fixup (dev, skb)) {
576 /* With RX_ASSEMBLE, rx_fixup() must update counters */
577 if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
578 dev->net->stats.rx_errors++;
579 return -EPROTO;
580 }
581 // else network stack removes extra byte if we forced a short packet
582
583 /* all data was already cloned from skb inside the driver */
584 if (dev->driver_info->flags & FLAG_MULTI_PACKET)
585 return -EALREADY;
586
587 if (skb->len < ETH_HLEN) {
588 dev->net->stats.rx_errors++;
589 dev->net->stats.rx_length_errors++;
590 netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
591 return -EPROTO;
592 }
593
594 usbnet_skb_return(dev, skb);
595 return 0;
596 }
597
598 /*-------------------------------------------------------------------------*/
599
rx_complete(struct urb * urb)600 static void rx_complete (struct urb *urb)
601 {
602 struct sk_buff *skb = (struct sk_buff *) urb->context;
603 struct skb_data *entry = (struct skb_data *) skb->cb;
604 struct usbnet *dev = entry->dev;
605 int urb_status = urb->status;
606 enum skb_state state;
607
608 skb_put (skb, urb->actual_length);
609 state = rx_done;
610 entry->urb = NULL;
611
612 switch (urb_status) {
613 /* success */
614 case 0:
615 break;
616
617 /* stalls need manual reset. this is rare ... except that
618 * when going through USB 2.0 TTs, unplug appears this way.
619 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
620 * storm, recovering as needed.
621 */
622 case -EPIPE:
623 dev->net->stats.rx_errors++;
624 usbnet_defer_kevent (dev, EVENT_RX_HALT);
625 fallthrough;
626
627 /* software-driven interface shutdown */
628 case -ECONNRESET: /* async unlink */
629 case -ESHUTDOWN: /* hardware gone */
630 netif_dbg(dev, ifdown, dev->net,
631 "rx shutdown, code %d\n", urb_status);
632 goto block;
633
634 /* we get controller i/o faults during hub_wq disconnect() delays.
635 * throttle down resubmits, to avoid log floods; just temporarily,
636 * so we still recover when the fault isn't a hub_wq delay.
637 */
638 case -EPROTO:
639 case -ETIME:
640 case -EILSEQ:
641 dev->net->stats.rx_errors++;
642 if (!timer_pending (&dev->delay)) {
643 mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
644 netif_dbg(dev, link, dev->net,
645 "rx throttle %d\n", urb_status);
646 }
647 block:
648 state = rx_cleanup;
649 entry->urb = urb;
650 urb = NULL;
651 break;
652
653 /* data overrun ... flush fifo? */
654 case -EOVERFLOW:
655 dev->net->stats.rx_over_errors++;
656 fallthrough;
657
658 default:
659 state = rx_cleanup;
660 dev->net->stats.rx_errors++;
661 netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
662 break;
663 }
664
665 /* stop rx if packet error rate is high */
666 if (++dev->pkt_cnt > 30) {
667 dev->pkt_cnt = 0;
668 dev->pkt_err = 0;
669 } else {
670 if (state == rx_cleanup)
671 dev->pkt_err++;
672 if (dev->pkt_err > 20)
673 set_bit(EVENT_RX_KILL, &dev->flags);
674 }
675
676 state = defer_bh(dev, skb, &dev->rxq, state);
677
678 if (urb) {
679 if (netif_running (dev->net) &&
680 !test_bit (EVENT_RX_HALT, &dev->flags) &&
681 state != unlink_start) {
682 rx_submit (dev, urb, GFP_ATOMIC);
683 usb_mark_last_busy(dev->udev);
684 return;
685 }
686 usb_free_urb (urb);
687 }
688 netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
689 }
690
691 /*-------------------------------------------------------------------------*/
usbnet_pause_rx(struct usbnet * dev)692 void usbnet_pause_rx(struct usbnet *dev)
693 {
694 set_bit(EVENT_RX_PAUSED, &dev->flags);
695
696 netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
697 }
698 EXPORT_SYMBOL_GPL(usbnet_pause_rx);
699
usbnet_resume_rx(struct usbnet * dev)700 void usbnet_resume_rx(struct usbnet *dev)
701 {
702 struct sk_buff *skb;
703 int num = 0;
704
705 clear_bit(EVENT_RX_PAUSED, &dev->flags);
706
707 while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
708 usbnet_skb_return(dev, skb);
709 num++;
710 }
711
712 tasklet_schedule(&dev->bh);
713
714 netif_dbg(dev, rx_status, dev->net,
715 "paused rx queue disabled, %d skbs requeued\n", num);
716 }
717 EXPORT_SYMBOL_GPL(usbnet_resume_rx);
718
usbnet_purge_paused_rxq(struct usbnet * dev)719 void usbnet_purge_paused_rxq(struct usbnet *dev)
720 {
721 skb_queue_purge(&dev->rxq_pause);
722 }
723 EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
724
725 /*-------------------------------------------------------------------------*/
726
727 // unlink pending rx/tx; completion handlers do all other cleanup
728
unlink_urbs(struct usbnet * dev,struct sk_buff_head * q)729 static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
730 {
731 unsigned long flags;
732 struct sk_buff *skb;
733 int count = 0;
734
735 spin_lock_irqsave (&q->lock, flags);
736 while (!skb_queue_empty(q)) {
737 struct skb_data *entry;
738 struct urb *urb;
739 int retval;
740
741 skb_queue_walk(q, skb) {
742 entry = (struct skb_data *) skb->cb;
743 if (entry->state != unlink_start)
744 goto found;
745 }
746 break;
747 found:
748 entry->state = unlink_start;
749 urb = entry->urb;
750
751 /*
752 * Get reference count of the URB to avoid it to be
753 * freed during usb_unlink_urb, which may trigger
754 * use-after-free problem inside usb_unlink_urb since
755 * usb_unlink_urb is always racing with .complete
756 * handler(include defer_bh).
757 */
758 usb_get_urb(urb);
759 spin_unlock_irqrestore(&q->lock, flags);
760 // during some PM-driven resume scenarios,
761 // these (async) unlinks complete immediately
762 retval = usb_unlink_urb (urb);
763 if (retval != -EINPROGRESS && retval != 0)
764 netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
765 else
766 count++;
767 usb_put_urb(urb);
768 spin_lock_irqsave(&q->lock, flags);
769 }
770 spin_unlock_irqrestore (&q->lock, flags);
771 return count;
772 }
773
774 // Flush all pending rx urbs
775 // minidrivers may need to do this when the MTU changes
776
usbnet_unlink_rx_urbs(struct usbnet * dev)777 void usbnet_unlink_rx_urbs(struct usbnet *dev)
778 {
779 if (netif_running(dev->net)) {
780 (void) unlink_urbs (dev, &dev->rxq);
781 tasklet_schedule(&dev->bh);
782 }
783 }
784 EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
785
786 /*-------------------------------------------------------------------------*/
787
wait_skb_queue_empty(struct sk_buff_head * q)788 static void wait_skb_queue_empty(struct sk_buff_head *q)
789 {
790 unsigned long flags;
791
792 spin_lock_irqsave(&q->lock, flags);
793 while (!skb_queue_empty(q)) {
794 spin_unlock_irqrestore(&q->lock, flags);
795 schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
796 set_current_state(TASK_UNINTERRUPTIBLE);
797 spin_lock_irqsave(&q->lock, flags);
798 }
799 spin_unlock_irqrestore(&q->lock, flags);
800 }
801
802 // precondition: never called in_interrupt
usbnet_terminate_urbs(struct usbnet * dev)803 static void usbnet_terminate_urbs(struct usbnet *dev)
804 {
805 DECLARE_WAITQUEUE(wait, current);
806 int temp;
807
808 /* ensure there are no more active urbs */
809 add_wait_queue(&dev->wait, &wait);
810 set_current_state(TASK_UNINTERRUPTIBLE);
811 temp = unlink_urbs(dev, &dev->txq) +
812 unlink_urbs(dev, &dev->rxq);
813
814 /* maybe wait for deletions to finish. */
815 wait_skb_queue_empty(&dev->rxq);
816 wait_skb_queue_empty(&dev->txq);
817 wait_skb_queue_empty(&dev->done);
818 netif_dbg(dev, ifdown, dev->net,
819 "waited for %d urb completions\n", temp);
820 set_current_state(TASK_RUNNING);
821 remove_wait_queue(&dev->wait, &wait);
822 }
823
usbnet_stop(struct net_device * net)824 int usbnet_stop (struct net_device *net)
825 {
826 struct usbnet *dev = netdev_priv(net);
827 const struct driver_info *info = dev->driver_info;
828 int retval, pm, mpn;
829
830 clear_bit(EVENT_DEV_OPEN, &dev->flags);
831 netif_stop_queue (net);
832
833 netif_info(dev, ifdown, dev->net,
834 "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
835 net->stats.rx_packets, net->stats.tx_packets,
836 net->stats.rx_errors, net->stats.tx_errors);
837
838 /* to not race resume */
839 pm = usb_autopm_get_interface(dev->intf);
840 /* allow minidriver to stop correctly (wireless devices to turn off
841 * radio etc) */
842 if (info->stop) {
843 retval = info->stop(dev);
844 if (retval < 0)
845 netif_info(dev, ifdown, dev->net,
846 "stop fail (%d) usbnet usb-%s-%s, %s\n",
847 retval,
848 dev->udev->bus->bus_name, dev->udev->devpath,
849 info->description);
850 }
851
852 if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
853 usbnet_terminate_urbs(dev);
854
855 usbnet_status_stop(dev);
856
857 usbnet_purge_paused_rxq(dev);
858
859 mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
860
861 /* deferred work (timer, softirq, task) must also stop */
862 dev->flags = 0;
863 del_timer_sync(&dev->delay);
864 tasklet_kill(&dev->bh);
865 cancel_work_sync(&dev->kevent);
866
867 /* We have cyclic dependencies. Those calls are needed
868 * to break a cycle. We cannot fall into the gaps because
869 * we have a flag
870 */
871 tasklet_kill(&dev->bh);
872 del_timer_sync(&dev->delay);
873 cancel_work_sync(&dev->kevent);
874
875 if (!pm)
876 usb_autopm_put_interface(dev->intf);
877
878 if (info->manage_power && mpn)
879 info->manage_power(dev, 0);
880 else
881 usb_autopm_put_interface(dev->intf);
882
883 return 0;
884 }
885 EXPORT_SYMBOL_GPL(usbnet_stop);
886
887 /*-------------------------------------------------------------------------*/
888
889 // posts reads, and enables write queuing
890
891 // precondition: never called in_interrupt
892
usbnet_open(struct net_device * net)893 int usbnet_open (struct net_device *net)
894 {
895 struct usbnet *dev = netdev_priv(net);
896 int retval;
897 const struct driver_info *info = dev->driver_info;
898
899 if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
900 netif_info(dev, ifup, dev->net,
901 "resumption fail (%d) usbnet usb-%s-%s, %s\n",
902 retval,
903 dev->udev->bus->bus_name,
904 dev->udev->devpath,
905 info->description);
906 goto done_nopm;
907 }
908
909 // put into "known safe" state
910 if (info->reset && (retval = info->reset (dev)) < 0) {
911 netif_info(dev, ifup, dev->net,
912 "open reset fail (%d) usbnet usb-%s-%s, %s\n",
913 retval,
914 dev->udev->bus->bus_name,
915 dev->udev->devpath,
916 info->description);
917 goto done;
918 }
919
920 /* hard_mtu or rx_urb_size may change in reset() */
921 usbnet_update_max_qlen(dev);
922
923 // insist peer be connected
924 if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
925 netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
926 goto done;
927 }
928
929 /* start any status interrupt transfer */
930 if (dev->interrupt) {
931 retval = usbnet_status_start(dev, GFP_KERNEL);
932 if (retval < 0) {
933 netif_err(dev, ifup, dev->net,
934 "intr submit %d\n", retval);
935 goto done;
936 }
937 }
938
939 set_bit(EVENT_DEV_OPEN, &dev->flags);
940 netif_start_queue (net);
941 netif_info(dev, ifup, dev->net,
942 "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
943 (int)RX_QLEN(dev), (int)TX_QLEN(dev),
944 dev->net->mtu,
945 (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
946 (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
947 (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
948 (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
949 (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
950 "simple");
951
952 /* reset rx error state */
953 dev->pkt_cnt = 0;
954 dev->pkt_err = 0;
955 clear_bit(EVENT_RX_KILL, &dev->flags);
956
957 // delay posting reads until we're fully open
958 tasklet_schedule (&dev->bh);
959 if (info->manage_power) {
960 retval = info->manage_power(dev, 1);
961 if (retval < 0) {
962 retval = 0;
963 set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
964 } else {
965 usb_autopm_put_interface(dev->intf);
966 }
967 }
968 return retval;
969 done:
970 usb_autopm_put_interface(dev->intf);
971 done_nopm:
972 return retval;
973 }
974 EXPORT_SYMBOL_GPL(usbnet_open);
975
976 /*-------------------------------------------------------------------------*/
977
978 /* ethtool methods; minidrivers may need to add some more, but
979 * they'll probably want to use this base set.
980 */
981
982 /* These methods are written on the assumption that the device
983 * uses MII
984 */
usbnet_get_link_ksettings_mii(struct net_device * net,struct ethtool_link_ksettings * cmd)985 int usbnet_get_link_ksettings_mii(struct net_device *net,
986 struct ethtool_link_ksettings *cmd)
987 {
988 struct usbnet *dev = netdev_priv(net);
989
990 if (!dev->mii.mdio_read)
991 return -EOPNOTSUPP;
992
993 mii_ethtool_get_link_ksettings(&dev->mii, cmd);
994
995 return 0;
996 }
997 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
998
usbnet_get_link_ksettings_internal(struct net_device * net,struct ethtool_link_ksettings * cmd)999 int usbnet_get_link_ksettings_internal(struct net_device *net,
1000 struct ethtool_link_ksettings *cmd)
1001 {
1002 struct usbnet *dev = netdev_priv(net);
1003
1004 /* the assumption that speed is equal on tx and rx
1005 * is deeply engrained into the networking layer.
1006 * For wireless stuff it is not true.
1007 * We assume that rx_speed matters more.
1008 */
1009 if (dev->rx_speed != SPEED_UNSET)
1010 cmd->base.speed = dev->rx_speed / 1000000;
1011 else if (dev->tx_speed != SPEED_UNSET)
1012 cmd->base.speed = dev->tx_speed / 1000000;
1013 else
1014 cmd->base.speed = SPEED_UNKNOWN;
1015
1016 return 0;
1017 }
1018 EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_internal);
1019
usbnet_set_link_ksettings_mii(struct net_device * net,const struct ethtool_link_ksettings * cmd)1020 int usbnet_set_link_ksettings_mii(struct net_device *net,
1021 const struct ethtool_link_ksettings *cmd)
1022 {
1023 struct usbnet *dev = netdev_priv(net);
1024 int retval;
1025
1026 if (!dev->mii.mdio_write)
1027 return -EOPNOTSUPP;
1028
1029 retval = mii_ethtool_set_link_ksettings(&dev->mii, cmd);
1030
1031 /* link speed/duplex might have changed */
1032 if (dev->driver_info->link_reset)
1033 dev->driver_info->link_reset(dev);
1034
1035 /* hard_mtu or rx_urb_size may change in link_reset() */
1036 usbnet_update_max_qlen(dev);
1037
1038 return retval;
1039 }
1040 EXPORT_SYMBOL_GPL(usbnet_set_link_ksettings_mii);
1041
usbnet_get_link(struct net_device * net)1042 u32 usbnet_get_link (struct net_device *net)
1043 {
1044 struct usbnet *dev = netdev_priv(net);
1045
1046 /* If a check_connect is defined, return its result */
1047 if (dev->driver_info->check_connect)
1048 return dev->driver_info->check_connect (dev) == 0;
1049
1050 /* if the device has mii operations, use those */
1051 if (dev->mii.mdio_read)
1052 return mii_link_ok(&dev->mii);
1053
1054 /* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
1055 return ethtool_op_get_link(net);
1056 }
1057 EXPORT_SYMBOL_GPL(usbnet_get_link);
1058
usbnet_nway_reset(struct net_device * net)1059 int usbnet_nway_reset(struct net_device *net)
1060 {
1061 struct usbnet *dev = netdev_priv(net);
1062
1063 if (!dev->mii.mdio_write)
1064 return -EOPNOTSUPP;
1065
1066 return mii_nway_restart(&dev->mii);
1067 }
1068 EXPORT_SYMBOL_GPL(usbnet_nway_reset);
1069
usbnet_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)1070 void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
1071 {
1072 struct usbnet *dev = netdev_priv(net);
1073
1074 strscpy(info->driver, dev->driver_name, sizeof(info->driver));
1075 strscpy(info->fw_version, dev->driver_info->description,
1076 sizeof(info->fw_version));
1077 usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
1078 }
1079 EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
1080
usbnet_get_msglevel(struct net_device * net)1081 u32 usbnet_get_msglevel (struct net_device *net)
1082 {
1083 struct usbnet *dev = netdev_priv(net);
1084
1085 return dev->msg_enable;
1086 }
1087 EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
1088
usbnet_set_msglevel(struct net_device * net,u32 level)1089 void usbnet_set_msglevel (struct net_device *net, u32 level)
1090 {
1091 struct usbnet *dev = netdev_priv(net);
1092
1093 dev->msg_enable = level;
1094 }
1095 EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
1096
1097 /* drivers may override default ethtool_ops in their bind() routine */
1098 static const struct ethtool_ops usbnet_ethtool_ops = {
1099 .get_link = usbnet_get_link,
1100 .nway_reset = usbnet_nway_reset,
1101 .get_drvinfo = usbnet_get_drvinfo,
1102 .get_msglevel = usbnet_get_msglevel,
1103 .set_msglevel = usbnet_set_msglevel,
1104 .get_ts_info = ethtool_op_get_ts_info,
1105 .get_link_ksettings = usbnet_get_link_ksettings_mii,
1106 .set_link_ksettings = usbnet_set_link_ksettings_mii,
1107 };
1108
1109 /*-------------------------------------------------------------------------*/
1110
__handle_link_change(struct usbnet * dev)1111 static void __handle_link_change(struct usbnet *dev)
1112 {
1113 if (!test_bit(EVENT_DEV_OPEN, &dev->flags))
1114 return;
1115
1116 if (test_and_clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags))
1117 netif_carrier_on(dev->net);
1118
1119 if (!netif_carrier_ok(dev->net)) {
1120 /* kill URBs for reading packets to save bus bandwidth */
1121 unlink_urbs(dev, &dev->rxq);
1122
1123 /*
1124 * tx_timeout will unlink URBs for sending packets and
1125 * tx queue is stopped by netcore after link becomes off
1126 */
1127 } else {
1128 /* submitting URBs for reading packets */
1129 tasklet_schedule(&dev->bh);
1130 }
1131
1132 /* hard_mtu or rx_urb_size may change during link change */
1133 usbnet_update_max_qlen(dev);
1134
1135 clear_bit(EVENT_LINK_CHANGE, &dev->flags);
1136 }
1137
usbnet_set_rx_mode(struct net_device * net)1138 void usbnet_set_rx_mode(struct net_device *net)
1139 {
1140 struct usbnet *dev = netdev_priv(net);
1141
1142 usbnet_defer_kevent(dev, EVENT_SET_RX_MODE);
1143 }
1144 EXPORT_SYMBOL_GPL(usbnet_set_rx_mode);
1145
__handle_set_rx_mode(struct usbnet * dev)1146 static void __handle_set_rx_mode(struct usbnet *dev)
1147 {
1148 if (dev->driver_info->set_rx_mode)
1149 (dev->driver_info->set_rx_mode)(dev);
1150
1151 clear_bit(EVENT_SET_RX_MODE, &dev->flags);
1152 }
1153
1154 /* work that cannot be done in interrupt context uses keventd.
1155 *
1156 * NOTE: with 2.5 we could do more of this using completion callbacks,
1157 * especially now that control transfers can be queued.
1158 */
1159 static void
usbnet_deferred_kevent(struct work_struct * work)1160 usbnet_deferred_kevent (struct work_struct *work)
1161 {
1162 struct usbnet *dev =
1163 container_of(work, struct usbnet, kevent);
1164 int status;
1165
1166 /* usb_clear_halt() needs a thread context */
1167 if (test_bit (EVENT_TX_HALT, &dev->flags)) {
1168 unlink_urbs (dev, &dev->txq);
1169 status = usb_autopm_get_interface(dev->intf);
1170 if (status < 0)
1171 goto fail_pipe;
1172 status = usb_clear_halt (dev->udev, dev->out);
1173 usb_autopm_put_interface(dev->intf);
1174 if (status < 0 &&
1175 status != -EPIPE &&
1176 status != -ESHUTDOWN) {
1177 if (netif_msg_tx_err (dev))
1178 fail_pipe:
1179 netdev_err(dev->net, "can't clear tx halt, status %d\n",
1180 status);
1181 } else {
1182 clear_bit (EVENT_TX_HALT, &dev->flags);
1183 if (status != -ESHUTDOWN)
1184 netif_wake_queue (dev->net);
1185 }
1186 }
1187 if (test_bit (EVENT_RX_HALT, &dev->flags)) {
1188 unlink_urbs (dev, &dev->rxq);
1189 status = usb_autopm_get_interface(dev->intf);
1190 if (status < 0)
1191 goto fail_halt;
1192 status = usb_clear_halt (dev->udev, dev->in);
1193 usb_autopm_put_interface(dev->intf);
1194 if (status < 0 &&
1195 status != -EPIPE &&
1196 status != -ESHUTDOWN) {
1197 if (netif_msg_rx_err (dev))
1198 fail_halt:
1199 netdev_err(dev->net, "can't clear rx halt, status %d\n",
1200 status);
1201 } else {
1202 clear_bit (EVENT_RX_HALT, &dev->flags);
1203 if (!usbnet_going_away(dev))
1204 tasklet_schedule(&dev->bh);
1205 }
1206 }
1207
1208 /* tasklet could resubmit itself forever if memory is tight */
1209 if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
1210 struct urb *urb = NULL;
1211 int resched = 1;
1212
1213 if (netif_running (dev->net))
1214 urb = usb_alloc_urb (0, GFP_KERNEL);
1215 else
1216 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1217 if (urb != NULL) {
1218 clear_bit (EVENT_RX_MEMORY, &dev->flags);
1219 status = usb_autopm_get_interface(dev->intf);
1220 if (status < 0) {
1221 usb_free_urb(urb);
1222 goto fail_lowmem;
1223 }
1224 if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
1225 resched = 0;
1226 usb_autopm_put_interface(dev->intf);
1227 fail_lowmem:
1228 if (resched)
1229 if (!usbnet_going_away(dev))
1230 tasklet_schedule(&dev->bh);
1231 }
1232 }
1233
1234 if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
1235 const struct driver_info *info = dev->driver_info;
1236 int retval = 0;
1237
1238 clear_bit (EVENT_LINK_RESET, &dev->flags);
1239 status = usb_autopm_get_interface(dev->intf);
1240 if (status < 0)
1241 goto skip_reset;
1242 if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1243 usb_autopm_put_interface(dev->intf);
1244 skip_reset:
1245 netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1246 retval,
1247 dev->udev->bus->bus_name,
1248 dev->udev->devpath,
1249 info->description);
1250 } else {
1251 usb_autopm_put_interface(dev->intf);
1252 }
1253
1254 /* handle link change from link resetting */
1255 __handle_link_change(dev);
1256 }
1257
1258 if (test_bit (EVENT_LINK_CHANGE, &dev->flags))
1259 __handle_link_change(dev);
1260
1261 if (test_bit (EVENT_SET_RX_MODE, &dev->flags))
1262 __handle_set_rx_mode(dev);
1263
1264
1265 if (dev->flags)
1266 netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1267 }
1268
1269 /*-------------------------------------------------------------------------*/
1270
tx_complete(struct urb * urb)1271 static void tx_complete (struct urb *urb)
1272 {
1273 struct sk_buff *skb = (struct sk_buff *) urb->context;
1274 struct skb_data *entry = (struct skb_data *) skb->cb;
1275 struct usbnet *dev = entry->dev;
1276
1277 if (urb->status == 0) {
1278 struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
1279 unsigned long flags;
1280
1281 flags = u64_stats_update_begin_irqsave(&stats64->syncp);
1282 u64_stats_add(&stats64->tx_packets, entry->packets);
1283 u64_stats_add(&stats64->tx_bytes, entry->length);
1284 u64_stats_update_end_irqrestore(&stats64->syncp, flags);
1285 } else {
1286 dev->net->stats.tx_errors++;
1287
1288 switch (urb->status) {
1289 case -EPIPE:
1290 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1291 break;
1292
1293 /* software-driven interface shutdown */
1294 case -ECONNRESET: // async unlink
1295 case -ESHUTDOWN: // hardware gone
1296 break;
1297
1298 /* like rx, tx gets controller i/o faults during hub_wq
1299 * delays and so it uses the same throttling mechanism.
1300 */
1301 case -EPROTO:
1302 case -ETIME:
1303 case -EILSEQ:
1304 usb_mark_last_busy(dev->udev);
1305 if (!timer_pending (&dev->delay)) {
1306 mod_timer (&dev->delay,
1307 jiffies + THROTTLE_JIFFIES);
1308 netif_dbg(dev, link, dev->net,
1309 "tx throttle %d\n", urb->status);
1310 }
1311 netif_stop_queue (dev->net);
1312 break;
1313 default:
1314 netif_dbg(dev, tx_err, dev->net,
1315 "tx err %d\n", entry->urb->status);
1316 break;
1317 }
1318 }
1319
1320 usb_autopm_put_interface_async(dev->intf);
1321 (void) defer_bh(dev, skb, &dev->txq, tx_done);
1322 }
1323
1324 /*-------------------------------------------------------------------------*/
1325
usbnet_tx_timeout(struct net_device * net,unsigned int txqueue)1326 void usbnet_tx_timeout (struct net_device *net, unsigned int txqueue)
1327 {
1328 struct usbnet *dev = netdev_priv(net);
1329
1330 unlink_urbs (dev, &dev->txq);
1331 tasklet_schedule (&dev->bh);
1332 /* this needs to be handled individually because the generic layer
1333 * doesn't know what is sufficient and could not restore private
1334 * information if a remedy of an unconditional reset were used.
1335 */
1336 if (dev->driver_info->recover)
1337 (dev->driver_info->recover)(dev);
1338 }
1339 EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1340
1341 /*-------------------------------------------------------------------------*/
1342
build_dma_sg(const struct sk_buff * skb,struct urb * urb)1343 static int build_dma_sg(const struct sk_buff *skb, struct urb *urb)
1344 {
1345 unsigned num_sgs, total_len = 0;
1346 int i, s = 0;
1347
1348 num_sgs = skb_shinfo(skb)->nr_frags + 1;
1349 if (num_sgs == 1)
1350 return 0;
1351
1352 /* reserve one for zero packet */
1353 urb->sg = kmalloc_array(num_sgs + 1, sizeof(struct scatterlist),
1354 GFP_ATOMIC);
1355 if (!urb->sg)
1356 return -ENOMEM;
1357
1358 urb->num_sgs = num_sgs;
1359 sg_init_table(urb->sg, urb->num_sgs + 1);
1360
1361 sg_set_buf(&urb->sg[s++], skb->data, skb_headlen(skb));
1362 total_len += skb_headlen(skb);
1363
1364 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1365 skb_frag_t *f = &skb_shinfo(skb)->frags[i];
1366
1367 total_len += skb_frag_size(f);
1368 sg_set_page(&urb->sg[i + s], skb_frag_page(f), skb_frag_size(f),
1369 skb_frag_off(f));
1370 }
1371 urb->transfer_buffer_length = total_len;
1372
1373 return 1;
1374 }
1375
usbnet_start_xmit(struct sk_buff * skb,struct net_device * net)1376 netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1377 struct net_device *net)
1378 {
1379 struct usbnet *dev = netdev_priv(net);
1380 unsigned int length;
1381 struct urb *urb = NULL;
1382 struct skb_data *entry;
1383 const struct driver_info *info = dev->driver_info;
1384 unsigned long flags;
1385 int retval;
1386
1387 if (skb)
1388 skb_tx_timestamp(skb);
1389
1390 // some devices want funky USB-level framing, for
1391 // win32 driver (usually) and/or hardware quirks
1392 if (info->tx_fixup) {
1393 skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1394 if (!skb) {
1395 /* packet collected; minidriver waiting for more */
1396 if (info->flags & FLAG_MULTI_PACKET)
1397 goto not_drop;
1398 netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1399 goto drop;
1400 }
1401 }
1402
1403 if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1404 netif_dbg(dev, tx_err, dev->net, "no urb\n");
1405 goto drop;
1406 }
1407
1408 entry = (struct skb_data *) skb->cb;
1409 entry->urb = urb;
1410 entry->dev = dev;
1411
1412 usb_fill_bulk_urb (urb, dev->udev, dev->out,
1413 skb->data, skb->len, tx_complete, skb);
1414 if (dev->can_dma_sg) {
1415 if (build_dma_sg(skb, urb) < 0)
1416 goto drop;
1417 }
1418 length = urb->transfer_buffer_length;
1419
1420 /* don't assume the hardware handles USB_ZERO_PACKET
1421 * NOTE: strictly conforming cdc-ether devices should expect
1422 * the ZLP here, but ignore the one-byte packet.
1423 * NOTE2: CDC NCM specification is different from CDC ECM when
1424 * handling ZLP/short packets, so cdc_ncm driver will make short
1425 * packet itself if needed.
1426 */
1427 if (length % dev->maxpacket == 0) {
1428 if (!(info->flags & FLAG_SEND_ZLP)) {
1429 if (!(info->flags & FLAG_MULTI_PACKET)) {
1430 length++;
1431 if (skb_tailroom(skb) && !urb->num_sgs) {
1432 skb->data[skb->len] = 0;
1433 __skb_put(skb, 1);
1434 } else if (urb->num_sgs)
1435 sg_set_buf(&urb->sg[urb->num_sgs++],
1436 dev->padding_pkt, 1);
1437 }
1438 } else
1439 urb->transfer_flags |= URB_ZERO_PACKET;
1440 }
1441 urb->transfer_buffer_length = length;
1442
1443 if (info->flags & FLAG_MULTI_PACKET) {
1444 /* Driver has set number of packets and a length delta.
1445 * Calculate the complete length and ensure that it's
1446 * positive.
1447 */
1448 entry->length += length;
1449 if (WARN_ON_ONCE(entry->length <= 0))
1450 entry->length = length;
1451 } else {
1452 usbnet_set_skb_tx_stats(skb, 1, length);
1453 }
1454
1455 spin_lock_irqsave(&dev->txq.lock, flags);
1456 retval = usb_autopm_get_interface_async(dev->intf);
1457 if (retval < 0) {
1458 spin_unlock_irqrestore(&dev->txq.lock, flags);
1459 goto drop;
1460 }
1461 if (netif_queue_stopped(net)) {
1462 usb_autopm_put_interface_async(dev->intf);
1463 spin_unlock_irqrestore(&dev->txq.lock, flags);
1464 goto drop;
1465 }
1466
1467 #ifdef CONFIG_PM
1468 /* if this triggers the device is still a sleep */
1469 if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1470 /* transmission will be done in resume */
1471 usb_anchor_urb(urb, &dev->deferred);
1472 /* no use to process more packets */
1473 netif_stop_queue(net);
1474 usb_put_urb(urb);
1475 spin_unlock_irqrestore(&dev->txq.lock, flags);
1476 netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1477 goto deferred;
1478 }
1479 #endif
1480
1481 switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1482 case -EPIPE:
1483 netif_stop_queue (net);
1484 usbnet_defer_kevent (dev, EVENT_TX_HALT);
1485 usb_autopm_put_interface_async(dev->intf);
1486 break;
1487 default:
1488 usb_autopm_put_interface_async(dev->intf);
1489 netif_dbg(dev, tx_err, dev->net,
1490 "tx: submit urb err %d\n", retval);
1491 break;
1492 case 0:
1493 netif_trans_update(net);
1494 __usbnet_queue_skb(&dev->txq, skb, tx_start);
1495 if (dev->txq.qlen >= TX_QLEN (dev))
1496 netif_stop_queue (net);
1497 }
1498 spin_unlock_irqrestore (&dev->txq.lock, flags);
1499
1500 if (retval) {
1501 netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1502 drop:
1503 dev->net->stats.tx_dropped++;
1504 not_drop:
1505 if (skb)
1506 dev_kfree_skb_any (skb);
1507 if (urb) {
1508 kfree(urb->sg);
1509 usb_free_urb(urb);
1510 }
1511 } else
1512 netif_dbg(dev, tx_queued, dev->net,
1513 "> tx, len %u, type 0x%x\n", length, skb->protocol);
1514 #ifdef CONFIG_PM
1515 deferred:
1516 #endif
1517 return NETDEV_TX_OK;
1518 }
1519 EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1520
rx_alloc_submit(struct usbnet * dev,gfp_t flags)1521 static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1522 {
1523 struct urb *urb;
1524 int i;
1525 int ret = 0;
1526
1527 /* don't refill the queue all at once */
1528 for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1529 urb = usb_alloc_urb(0, flags);
1530 if (urb != NULL) {
1531 ret = rx_submit(dev, urb, flags);
1532 if (ret)
1533 goto err;
1534 } else {
1535 ret = -ENOMEM;
1536 goto err;
1537 }
1538 }
1539 err:
1540 return ret;
1541 }
1542
usb_free_skb(struct sk_buff * skb)1543 static inline void usb_free_skb(struct sk_buff *skb)
1544 {
1545 struct skb_data *entry = (struct skb_data *)skb->cb;
1546
1547 usb_free_urb(entry->urb);
1548 dev_kfree_skb(skb);
1549 }
1550
1551 /*-------------------------------------------------------------------------*/
1552
1553 // tasklet (work deferred from completions, in_irq) or timer
1554
usbnet_bh(struct timer_list * t)1555 static void usbnet_bh (struct timer_list *t)
1556 {
1557 struct usbnet *dev = from_timer(dev, t, delay);
1558 struct sk_buff *skb;
1559 struct skb_data *entry;
1560
1561 while ((skb = skb_dequeue (&dev->done))) {
1562 entry = (struct skb_data *) skb->cb;
1563 switch (entry->state) {
1564 case rx_done:
1565 if (rx_process(dev, skb))
1566 usb_free_skb(skb);
1567 continue;
1568 case tx_done:
1569 kfree(entry->urb->sg);
1570 fallthrough;
1571 case rx_cleanup:
1572 usb_free_skb(skb);
1573 continue;
1574 default:
1575 netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1576 }
1577 }
1578
1579 /* restart RX again after disabling due to high error rate */
1580 clear_bit(EVENT_RX_KILL, &dev->flags);
1581
1582 /* waiting for all pending urbs to complete?
1583 * only then can we forgo submitting anew
1584 */
1585 if (waitqueue_active(&dev->wait)) {
1586 if (dev->txq.qlen + dev->rxq.qlen + dev->done.qlen == 0)
1587 wake_up_all(&dev->wait);
1588
1589 // or are we maybe short a few urbs?
1590 } else if (netif_running (dev->net) &&
1591 netif_device_present (dev->net) &&
1592 netif_carrier_ok(dev->net) &&
1593 !usbnet_going_away(dev) &&
1594 !timer_pending(&dev->delay) &&
1595 !test_bit(EVENT_RX_PAUSED, &dev->flags) &&
1596 !test_bit(EVENT_RX_HALT, &dev->flags)) {
1597 int temp = dev->rxq.qlen;
1598
1599 if (temp < RX_QLEN(dev)) {
1600 if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1601 return;
1602 if (temp != dev->rxq.qlen)
1603 netif_dbg(dev, link, dev->net,
1604 "rxqlen %d --> %d\n",
1605 temp, dev->rxq.qlen);
1606 if (dev->rxq.qlen < RX_QLEN(dev))
1607 tasklet_schedule (&dev->bh);
1608 }
1609 if (dev->txq.qlen < TX_QLEN (dev))
1610 netif_wake_queue (dev->net);
1611 }
1612 }
1613
usbnet_bh_tasklet(struct tasklet_struct * t)1614 static void usbnet_bh_tasklet(struct tasklet_struct *t)
1615 {
1616 struct usbnet *dev = from_tasklet(dev, t, bh);
1617
1618 usbnet_bh(&dev->delay);
1619 }
1620
1621
1622 /*-------------------------------------------------------------------------
1623 *
1624 * USB Device Driver support
1625 *
1626 *-------------------------------------------------------------------------*/
1627
1628 // precondition: never called in_interrupt
1629
usbnet_disconnect(struct usb_interface * intf)1630 void usbnet_disconnect (struct usb_interface *intf)
1631 {
1632 struct usbnet *dev;
1633 struct usb_device *xdev;
1634 struct net_device *net;
1635 struct urb *urb;
1636
1637 dev = usb_get_intfdata(intf);
1638 usb_set_intfdata(intf, NULL);
1639 if (!dev)
1640 return;
1641 usbnet_mark_going_away(dev);
1642
1643 xdev = interface_to_usbdev (intf);
1644
1645 netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1646 intf->dev.driver->name,
1647 xdev->bus->bus_name, xdev->devpath,
1648 dev->driver_info->description);
1649
1650 net = dev->net;
1651 unregister_netdev (net);
1652
1653 while ((urb = usb_get_from_anchor(&dev->deferred))) {
1654 dev_kfree_skb(urb->context);
1655 kfree(urb->sg);
1656 usb_free_urb(urb);
1657 }
1658
1659 if (dev->driver_info->unbind)
1660 dev->driver_info->unbind(dev, intf);
1661
1662 usb_kill_urb(dev->interrupt);
1663 usb_free_urb(dev->interrupt);
1664 kfree(dev->padding_pkt);
1665
1666 free_netdev(net);
1667 }
1668 EXPORT_SYMBOL_GPL(usbnet_disconnect);
1669
1670 static const struct net_device_ops usbnet_netdev_ops = {
1671 .ndo_open = usbnet_open,
1672 .ndo_stop = usbnet_stop,
1673 .ndo_start_xmit = usbnet_start_xmit,
1674 .ndo_tx_timeout = usbnet_tx_timeout,
1675 .ndo_set_rx_mode = usbnet_set_rx_mode,
1676 .ndo_change_mtu = usbnet_change_mtu,
1677 .ndo_set_mac_address = eth_mac_addr,
1678 .ndo_validate_addr = eth_validate_addr,
1679 };
1680
1681 /*-------------------------------------------------------------------------*/
1682
1683 // precondition: never called in_interrupt
1684
1685 static const struct device_type wlan_type = {
1686 .name = "wlan",
1687 };
1688
1689 static const struct device_type wwan_type = {
1690 .name = "wwan",
1691 };
1692
1693 int
usbnet_probe(struct usb_interface * udev,const struct usb_device_id * prod)1694 usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1695 {
1696 struct usbnet *dev;
1697 struct net_device *net;
1698 struct usb_host_interface *interface;
1699 const struct driver_info *info;
1700 struct usb_device *xdev;
1701 int status;
1702 const char *name;
1703 struct usb_driver *driver = to_usb_driver(udev->dev.driver);
1704
1705 /* usbnet already took usb runtime pm, so have to enable the feature
1706 * for usb interface, otherwise usb_autopm_get_interface may return
1707 * failure if RUNTIME_PM is enabled.
1708 */
1709 if (!driver->supports_autosuspend) {
1710 driver->supports_autosuspend = 1;
1711 pm_runtime_enable(&udev->dev);
1712 }
1713
1714 name = udev->dev.driver->name;
1715 info = (const struct driver_info *) prod->driver_info;
1716 if (!info) {
1717 dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1718 return -ENODEV;
1719 }
1720 xdev = interface_to_usbdev (udev);
1721 interface = udev->cur_altsetting;
1722
1723 status = -ENOMEM;
1724
1725 // set up our own records
1726 net = alloc_etherdev(sizeof(*dev));
1727 if (!net)
1728 goto out;
1729
1730 /* netdev_printk() needs this so do it as early as possible */
1731 SET_NETDEV_DEV(net, &udev->dev);
1732
1733 dev = netdev_priv(net);
1734 dev->udev = xdev;
1735 dev->intf = udev;
1736 dev->driver_info = info;
1737 dev->driver_name = name;
1738 dev->rx_speed = SPEED_UNSET;
1739 dev->tx_speed = SPEED_UNSET;
1740
1741 dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1742 | NETIF_MSG_PROBE | NETIF_MSG_LINK);
1743 init_waitqueue_head(&dev->wait);
1744 skb_queue_head_init (&dev->rxq);
1745 skb_queue_head_init (&dev->txq);
1746 skb_queue_head_init (&dev->done);
1747 skb_queue_head_init(&dev->rxq_pause);
1748 tasklet_setup(&dev->bh, usbnet_bh_tasklet);
1749 INIT_WORK (&dev->kevent, usbnet_deferred_kevent);
1750 init_usb_anchor(&dev->deferred);
1751 timer_setup(&dev->delay, usbnet_bh, 0);
1752 mutex_init (&dev->phy_mutex);
1753 mutex_init(&dev->interrupt_mutex);
1754 dev->interrupt_count = 0;
1755
1756 dev->net = net;
1757 strscpy(net->name, "usb%d", sizeof(net->name));
1758
1759 /* rx and tx sides can use different message sizes;
1760 * bind() should set rx_urb_size in that case.
1761 */
1762 dev->hard_mtu = net->mtu + net->hard_header_len;
1763 net->min_mtu = 0;
1764 net->max_mtu = ETH_MAX_MTU;
1765 net->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1766
1767 net->netdev_ops = &usbnet_netdev_ops;
1768 net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1769 net->ethtool_ops = &usbnet_ethtool_ops;
1770 net->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
1771
1772 // allow device-specific bind/init procedures
1773 // NOTE net->name still not usable ...
1774 if (info->bind) {
1775 status = info->bind (dev, udev);
1776 if (status < 0)
1777 goto out1;
1778
1779 /* heuristic: rename to "eth%d" if we are not sure this link
1780 * is two-host (these links keep "usb%d")
1781 */
1782 if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1783 !usbnet_needs_usb_name_format(dev, net))
1784 strscpy(net->name, "eth%d", sizeof(net->name));
1785 /* WLAN devices should always be named "wlan%d" */
1786 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1787 strscpy(net->name, "wlan%d", sizeof(net->name));
1788 /* WWAN devices should always be named "wwan%d" */
1789 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1790 strscpy(net->name, "wwan%d", sizeof(net->name));
1791
1792 /* devices that cannot do ARP */
1793 if ((dev->driver_info->flags & FLAG_NOARP) != 0)
1794 net->flags |= IFF_NOARP;
1795
1796 /* maybe the remote can't receive an Ethernet MTU */
1797 if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1798 net->mtu = dev->hard_mtu - net->hard_header_len;
1799 } else if (!info->in || !info->out)
1800 status = usbnet_get_endpoints (dev, udev);
1801 else {
1802 u8 ep_addrs[3] = {
1803 info->in + USB_DIR_IN, info->out + USB_DIR_OUT, 0
1804 };
1805
1806 dev->in = usb_rcvbulkpipe (xdev, info->in);
1807 dev->out = usb_sndbulkpipe (xdev, info->out);
1808 if (!(info->flags & FLAG_NO_SETINT))
1809 status = usb_set_interface (xdev,
1810 interface->desc.bInterfaceNumber,
1811 interface->desc.bAlternateSetting);
1812 else
1813 status = 0;
1814
1815 if (status == 0 && !usb_check_bulk_endpoints(udev, ep_addrs))
1816 status = -EINVAL;
1817 }
1818 if (status >= 0 && dev->status)
1819 status = init_status (dev, udev);
1820 if (status < 0)
1821 goto out3;
1822
1823 if (!dev->rx_urb_size)
1824 dev->rx_urb_size = dev->hard_mtu;
1825 dev->maxpacket = usb_maxpacket(dev->udev, dev->out);
1826 if (dev->maxpacket == 0) {
1827 /* that is a broken device */
1828 status = -ENODEV;
1829 goto out4;
1830 }
1831
1832 /* this flags the device for user space */
1833 if (!is_valid_ether_addr(net->dev_addr))
1834 eth_hw_addr_random(net);
1835
1836 if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1837 SET_NETDEV_DEVTYPE(net, &wlan_type);
1838 if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1839 SET_NETDEV_DEVTYPE(net, &wwan_type);
1840
1841 /* initialize max rx_qlen and tx_qlen */
1842 usbnet_update_max_qlen(dev);
1843
1844 if (dev->can_dma_sg && !(info->flags & FLAG_SEND_ZLP) &&
1845 !(info->flags & FLAG_MULTI_PACKET)) {
1846 dev->padding_pkt = kzalloc(1, GFP_KERNEL);
1847 if (!dev->padding_pkt) {
1848 status = -ENOMEM;
1849 goto out4;
1850 }
1851 }
1852
1853 status = register_netdev (net);
1854 if (status)
1855 goto out5;
1856 netif_info(dev, probe, dev->net,
1857 "register '%s' at usb-%s-%s, %s, %pM\n",
1858 udev->dev.driver->name,
1859 xdev->bus->bus_name, xdev->devpath,
1860 dev->driver_info->description,
1861 net->dev_addr);
1862
1863 // ok, it's ready to go.
1864 usb_set_intfdata (udev, dev);
1865
1866 netif_device_attach (net);
1867
1868 if (dev->driver_info->flags & FLAG_LINK_INTR)
1869 usbnet_link_change(dev, 0, 0);
1870
1871 return 0;
1872
1873 out5:
1874 kfree(dev->padding_pkt);
1875 out4:
1876 usb_free_urb(dev->interrupt);
1877 out3:
1878 if (info->unbind)
1879 info->unbind (dev, udev);
1880 out1:
1881 /* subdrivers must undo all they did in bind() if they
1882 * fail it, but we may fail later and a deferred kevent
1883 * may trigger an error resubmitting itself and, worse,
1884 * schedule a timer. So we kill it all just in case.
1885 */
1886 usbnet_mark_going_away(dev);
1887 cancel_work_sync(&dev->kevent);
1888 del_timer_sync(&dev->delay);
1889 free_netdev(net);
1890 out:
1891 return status;
1892 }
1893 EXPORT_SYMBOL_GPL(usbnet_probe);
1894
1895 /*-------------------------------------------------------------------------*/
1896
1897 /*
1898 * suspend the whole driver as soon as the first interface is suspended
1899 * resume only when the last interface is resumed
1900 */
1901
usbnet_suspend(struct usb_interface * intf,pm_message_t message)1902 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1903 {
1904 struct usbnet *dev = usb_get_intfdata(intf);
1905
1906 if (!dev->suspend_count++) {
1907 spin_lock_irq(&dev->txq.lock);
1908 /* don't autosuspend while transmitting */
1909 if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1910 dev->suspend_count--;
1911 spin_unlock_irq(&dev->txq.lock);
1912 return -EBUSY;
1913 } else {
1914 set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1915 spin_unlock_irq(&dev->txq.lock);
1916 }
1917 /*
1918 * accelerate emptying of the rx and queues, to avoid
1919 * having everything error out.
1920 */
1921 netif_device_detach (dev->net);
1922 usbnet_terminate_urbs(dev);
1923 __usbnet_status_stop_force(dev);
1924
1925 /*
1926 * reattach so runtime management can use and
1927 * wake the device
1928 */
1929 netif_device_attach (dev->net);
1930 }
1931 return 0;
1932 }
1933 EXPORT_SYMBOL_GPL(usbnet_suspend);
1934
usbnet_resume(struct usb_interface * intf)1935 int usbnet_resume (struct usb_interface *intf)
1936 {
1937 struct usbnet *dev = usb_get_intfdata(intf);
1938 struct sk_buff *skb;
1939 struct urb *res;
1940 int retval;
1941
1942 if (!--dev->suspend_count) {
1943 /* resume interrupt URB if it was previously submitted */
1944 __usbnet_status_start_force(dev, GFP_NOIO);
1945
1946 spin_lock_irq(&dev->txq.lock);
1947 while ((res = usb_get_from_anchor(&dev->deferred))) {
1948
1949 skb = (struct sk_buff *)res->context;
1950 retval = usb_submit_urb(res, GFP_ATOMIC);
1951 if (retval < 0) {
1952 dev_kfree_skb_any(skb);
1953 kfree(res->sg);
1954 usb_free_urb(res);
1955 usb_autopm_put_interface_async(dev->intf);
1956 } else {
1957 netif_trans_update(dev->net);
1958 __skb_queue_tail(&dev->txq, skb);
1959 }
1960 }
1961
1962 smp_mb();
1963 clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1964 spin_unlock_irq(&dev->txq.lock);
1965
1966 if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1967 /* handle remote wakeup ASAP
1968 * we cannot race against stop
1969 */
1970 if (netif_device_present(dev->net) &&
1971 !timer_pending(&dev->delay) &&
1972 !test_bit(EVENT_RX_HALT, &dev->flags))
1973 rx_alloc_submit(dev, GFP_NOIO);
1974
1975 if (!(dev->txq.qlen >= TX_QLEN(dev)))
1976 netif_tx_wake_all_queues(dev->net);
1977 tasklet_schedule (&dev->bh);
1978 }
1979 }
1980
1981 if (test_and_clear_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags))
1982 usb_autopm_get_interface_no_resume(intf);
1983
1984 return 0;
1985 }
1986 EXPORT_SYMBOL_GPL(usbnet_resume);
1987
1988 /*
1989 * Either a subdriver implements manage_power, then it is assumed to always
1990 * be ready to be suspended or it reports the readiness to be suspended
1991 * explicitly
1992 */
usbnet_device_suggests_idle(struct usbnet * dev)1993 void usbnet_device_suggests_idle(struct usbnet *dev)
1994 {
1995 if (!test_and_set_bit(EVENT_DEVICE_REPORT_IDLE, &dev->flags)) {
1996 dev->intf->needs_remote_wakeup = 1;
1997 usb_autopm_put_interface_async(dev->intf);
1998 }
1999 }
2000 EXPORT_SYMBOL(usbnet_device_suggests_idle);
2001
2002 /*
2003 * For devices that can do without special commands
2004 */
usbnet_manage_power(struct usbnet * dev,int on)2005 int usbnet_manage_power(struct usbnet *dev, int on)
2006 {
2007 dev->intf->needs_remote_wakeup = on;
2008 return 0;
2009 }
2010 EXPORT_SYMBOL(usbnet_manage_power);
2011
usbnet_link_change(struct usbnet * dev,bool link,bool need_reset)2012 void usbnet_link_change(struct usbnet *dev, bool link, bool need_reset)
2013 {
2014 /* update link after link is reseted */
2015 if (link && !need_reset) {
2016 set_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2017 } else {
2018 clear_bit(EVENT_LINK_CARRIER_ON, &dev->flags);
2019 netif_carrier_off(dev->net);
2020 }
2021
2022 if (need_reset && link)
2023 usbnet_defer_kevent(dev, EVENT_LINK_RESET);
2024 else
2025 usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
2026 }
2027 EXPORT_SYMBOL(usbnet_link_change);
2028
2029 /*-------------------------------------------------------------------------*/
__usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2030 static int __usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2031 u16 value, u16 index, void *data, u16 size)
2032 {
2033 void *buf = NULL;
2034 int err = -ENOMEM;
2035
2036 netdev_dbg(dev->net, "usbnet_read_cmd cmd=0x%02x reqtype=%02x"
2037 " value=0x%04x index=0x%04x size=%d\n",
2038 cmd, reqtype, value, index, size);
2039
2040 if (size) {
2041 buf = kmalloc(size, GFP_NOIO);
2042 if (!buf)
2043 goto out;
2044 }
2045
2046 err = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
2047 cmd, reqtype, value, index, buf, size,
2048 USB_CTRL_GET_TIMEOUT);
2049 if (err > 0 && err <= size) {
2050 if (data)
2051 memcpy(data, buf, err);
2052 else
2053 netdev_dbg(dev->net,
2054 "Huh? Data requested but thrown away.\n");
2055 }
2056 kfree(buf);
2057 out:
2058 return err;
2059 }
2060
__usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2061 static int __usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2062 u16 value, u16 index, const void *data,
2063 u16 size)
2064 {
2065 void *buf = NULL;
2066 int err = -ENOMEM;
2067
2068 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2069 " value=0x%04x index=0x%04x size=%d\n",
2070 cmd, reqtype, value, index, size);
2071
2072 if (data) {
2073 buf = kmemdup(data, size, GFP_NOIO);
2074 if (!buf)
2075 goto out;
2076 } else {
2077 if (size) {
2078 WARN_ON_ONCE(1);
2079 err = -EINVAL;
2080 goto out;
2081 }
2082 }
2083
2084 err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0),
2085 cmd, reqtype, value, index, buf, size,
2086 USB_CTRL_SET_TIMEOUT);
2087 kfree(buf);
2088
2089 out:
2090 return err;
2091 }
2092
2093 /*
2094 * The function can't be called inside suspend/resume callback,
2095 * otherwise deadlock will be caused.
2096 */
usbnet_read_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2097 int usbnet_read_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2098 u16 value, u16 index, void *data, u16 size)
2099 {
2100 int ret;
2101
2102 if (usb_autopm_get_interface(dev->intf) < 0)
2103 return -ENODEV;
2104 ret = __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2105 data, size);
2106 usb_autopm_put_interface(dev->intf);
2107 return ret;
2108 }
2109 EXPORT_SYMBOL_GPL(usbnet_read_cmd);
2110
2111 /*
2112 * The function can't be called inside suspend/resume callback,
2113 * otherwise deadlock will be caused.
2114 */
usbnet_write_cmd(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2115 int usbnet_write_cmd(struct usbnet *dev, u8 cmd, u8 reqtype,
2116 u16 value, u16 index, const void *data, u16 size)
2117 {
2118 int ret;
2119
2120 if (usb_autopm_get_interface(dev->intf) < 0)
2121 return -ENODEV;
2122 ret = __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2123 data, size);
2124 usb_autopm_put_interface(dev->intf);
2125 return ret;
2126 }
2127 EXPORT_SYMBOL_GPL(usbnet_write_cmd);
2128
2129 /*
2130 * The function can be called inside suspend/resume callback safely
2131 * and should only be called by suspend/resume callback generally.
2132 */
usbnet_read_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,void * data,u16 size)2133 int usbnet_read_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2134 u16 value, u16 index, void *data, u16 size)
2135 {
2136 return __usbnet_read_cmd(dev, cmd, reqtype, value, index,
2137 data, size);
2138 }
2139 EXPORT_SYMBOL_GPL(usbnet_read_cmd_nopm);
2140
2141 /*
2142 * The function can be called inside suspend/resume callback safely
2143 * and should only be called by suspend/resume callback generally.
2144 */
usbnet_write_cmd_nopm(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2145 int usbnet_write_cmd_nopm(struct usbnet *dev, u8 cmd, u8 reqtype,
2146 u16 value, u16 index, const void *data,
2147 u16 size)
2148 {
2149 return __usbnet_write_cmd(dev, cmd, reqtype, value, index,
2150 data, size);
2151 }
2152 EXPORT_SYMBOL_GPL(usbnet_write_cmd_nopm);
2153
usbnet_async_cmd_cb(struct urb * urb)2154 static void usbnet_async_cmd_cb(struct urb *urb)
2155 {
2156 struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
2157 int status = urb->status;
2158
2159 if (status < 0)
2160 dev_dbg(&urb->dev->dev, "%s failed with %d",
2161 __func__, status);
2162
2163 kfree(req);
2164 usb_free_urb(urb);
2165 }
2166
2167 /*
2168 * The caller must make sure that device can't be put into suspend
2169 * state until the control URB completes.
2170 */
usbnet_write_cmd_async(struct usbnet * dev,u8 cmd,u8 reqtype,u16 value,u16 index,const void * data,u16 size)2171 int usbnet_write_cmd_async(struct usbnet *dev, u8 cmd, u8 reqtype,
2172 u16 value, u16 index, const void *data, u16 size)
2173 {
2174 struct usb_ctrlrequest *req;
2175 struct urb *urb;
2176 int err = -ENOMEM;
2177 void *buf = NULL;
2178
2179 netdev_dbg(dev->net, "usbnet_write_cmd cmd=0x%02x reqtype=%02x"
2180 " value=0x%04x index=0x%04x size=%d\n",
2181 cmd, reqtype, value, index, size);
2182
2183 urb = usb_alloc_urb(0, GFP_ATOMIC);
2184 if (!urb)
2185 goto fail;
2186
2187 if (data) {
2188 buf = kmemdup(data, size, GFP_ATOMIC);
2189 if (!buf) {
2190 netdev_err(dev->net, "Error allocating buffer"
2191 " in %s!\n", __func__);
2192 goto fail_free_urb;
2193 }
2194 }
2195
2196 req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
2197 if (!req)
2198 goto fail_free_buf;
2199
2200 req->bRequestType = reqtype;
2201 req->bRequest = cmd;
2202 req->wValue = cpu_to_le16(value);
2203 req->wIndex = cpu_to_le16(index);
2204 req->wLength = cpu_to_le16(size);
2205
2206 usb_fill_control_urb(urb, dev->udev,
2207 usb_sndctrlpipe(dev->udev, 0),
2208 (void *)req, buf, size,
2209 usbnet_async_cmd_cb, req);
2210 urb->transfer_flags |= URB_FREE_BUFFER;
2211
2212 err = usb_submit_urb(urb, GFP_ATOMIC);
2213 if (err < 0) {
2214 netdev_err(dev->net, "Error submitting the control"
2215 " message: status=%d\n", err);
2216 goto fail_free_all;
2217 }
2218 return 0;
2219
2220 fail_free_all:
2221 kfree(req);
2222 fail_free_buf:
2223 kfree(buf);
2224 /*
2225 * avoid a double free
2226 * needed because the flag can be set only
2227 * after filling the URB
2228 */
2229 urb->transfer_flags = 0;
2230 fail_free_urb:
2231 usb_free_urb(urb);
2232 fail:
2233 return err;
2234
2235 }
2236 EXPORT_SYMBOL_GPL(usbnet_write_cmd_async);
2237 /*-------------------------------------------------------------------------*/
2238
usbnet_init(void)2239 static int __init usbnet_init(void)
2240 {
2241 /* Compiler should optimize this out. */
2242 BUILD_BUG_ON(
2243 sizeof_field(struct sk_buff, cb) < sizeof(struct skb_data));
2244
2245 return 0;
2246 }
2247 module_init(usbnet_init);
2248
usbnet_exit(void)2249 static void __exit usbnet_exit(void)
2250 {
2251 }
2252 module_exit(usbnet_exit);
2253
2254 MODULE_AUTHOR("David Brownell");
2255 MODULE_DESCRIPTION("USB network driver framework");
2256 MODULE_LICENSE("GPL");
2257