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path: root/drivers/usb/gadget/function/u_ether.c
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-rw-r--r--drivers/usb/gadget/function/u_ether.c1182
1 files changed, 1182 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c
new file mode 100644
index 000000000000..d50adda913cf
--- /dev/null
+++ b/drivers/usb/gadget/function/u_ether.c
@@ -0,0 +1,1182 @@
1/*
2 * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
3 *
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14/* #define VERBOSE_DEBUG */
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/gfp.h>
19#include <linux/device.h>
20#include <linux/ctype.h>
21#include <linux/etherdevice.h>
22#include <linux/ethtool.h>
23#include <linux/if_vlan.h>
24
25#include "u_ether.h"
26
27
28/*
29 * This component encapsulates the Ethernet link glue needed to provide
30 * one (!) network link through the USB gadget stack, normally "usb0".
31 *
32 * The control and data models are handled by the function driver which
33 * connects to this code; such as CDC Ethernet (ECM or EEM),
34 * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
35 * management.
36 *
37 * Link level addressing is handled by this component using module
38 * parameters; if no such parameters are provided, random link level
39 * addresses are used. Each end of the link uses one address. The
40 * host end address is exported in various ways, and is often recorded
41 * in configuration databases.
42 *
43 * The driver which assembles each configuration using such a link is
44 * responsible for ensuring that each configuration includes at most one
45 * instance of is network link. (The network layer provides ways for
46 * this single "physical" link to be used by multiple virtual links.)
47 */
48
49#define UETH__VERSION "29-May-2008"
50
51struct eth_dev {
52 /* lock is held while accessing port_usb
53 */
54 spinlock_t lock;
55 struct gether *port_usb;
56
57 struct net_device *net;
58 struct usb_gadget *gadget;
59
60 spinlock_t req_lock; /* guard {rx,tx}_reqs */
61 struct list_head tx_reqs, rx_reqs;
62 atomic_t tx_qlen;
63
64 struct sk_buff_head rx_frames;
65
66 unsigned qmult;
67
68 unsigned header_len;
69 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
70 int (*unwrap)(struct gether *,
71 struct sk_buff *skb,
72 struct sk_buff_head *list);
73
74 struct work_struct work;
75
76 unsigned long todo;
77#define WORK_RX_MEMORY 0
78
79 bool zlp;
80 u8 host_mac[ETH_ALEN];
81 u8 dev_mac[ETH_ALEN];
82};
83
84/*-------------------------------------------------------------------------*/
85
86#define RX_EXTRA 20 /* bytes guarding against rx overflows */
87
88#define DEFAULT_QLEN 2 /* double buffering by default */
89
90/* for dual-speed hardware, use deeper queues at high/super speed */
91static inline int qlen(struct usb_gadget *gadget, unsigned qmult)
92{
93 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
94 gadget->speed == USB_SPEED_SUPER))
95 return qmult * DEFAULT_QLEN;
96 else
97 return DEFAULT_QLEN;
98}
99
100/*-------------------------------------------------------------------------*/
101
102/* REVISIT there must be a better way than having two sets
103 * of debug calls ...
104 */
105
106#undef DBG
107#undef VDBG
108#undef ERROR
109#undef INFO
110
111#define xprintk(d, level, fmt, args...) \
112 printk(level "%s: " fmt , (d)->net->name , ## args)
113
114#ifdef DEBUG
115#undef DEBUG
116#define DBG(dev, fmt, args...) \
117 xprintk(dev , KERN_DEBUG , fmt , ## args)
118#else
119#define DBG(dev, fmt, args...) \
120 do { } while (0)
121#endif /* DEBUG */
122
123#ifdef VERBOSE_DEBUG
124#define VDBG DBG
125#else
126#define VDBG(dev, fmt, args...) \
127 do { } while (0)
128#endif /* DEBUG */
129
130#define ERROR(dev, fmt, args...) \
131 xprintk(dev , KERN_ERR , fmt , ## args)
132#define INFO(dev, fmt, args...) \
133 xprintk(dev , KERN_INFO , fmt , ## args)
134
135/*-------------------------------------------------------------------------*/
136
137/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
138
139static int ueth_change_mtu(struct net_device *net, int new_mtu)
140{
141 struct eth_dev *dev = netdev_priv(net);
142 unsigned long flags;
143 int status = 0;
144
145 /* don't change MTU on "live" link (peer won't know) */
146 spin_lock_irqsave(&dev->lock, flags);
147 if (dev->port_usb)
148 status = -EBUSY;
149 else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
150 status = -ERANGE;
151 else
152 net->mtu = new_mtu;
153 spin_unlock_irqrestore(&dev->lock, flags);
154
155 return status;
156}
157
158static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
159{
160 struct eth_dev *dev = netdev_priv(net);
161
162 strlcpy(p->driver, "g_ether", sizeof(p->driver));
163 strlcpy(p->version, UETH__VERSION, sizeof(p->version));
164 strlcpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version));
165 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info));
166}
167
168/* REVISIT can also support:
169 * - WOL (by tracking suspends and issuing remote wakeup)
170 * - msglevel (implies updated messaging)
171 * - ... probably more ethtool ops
172 */
173
174static const struct ethtool_ops ops = {
175 .get_drvinfo = eth_get_drvinfo,
176 .get_link = ethtool_op_get_link,
177};
178
179static void defer_kevent(struct eth_dev *dev, int flag)
180{
181 if (test_and_set_bit(flag, &dev->todo))
182 return;
183 if (!schedule_work(&dev->work))
184 ERROR(dev, "kevent %d may have been dropped\n", flag);
185 else
186 DBG(dev, "kevent %d scheduled\n", flag);
187}
188
189static void rx_complete(struct usb_ep *ep, struct usb_request *req);
190
191static int
192rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
193{
194 struct sk_buff *skb;
195 int retval = -ENOMEM;
196 size_t size = 0;
197 struct usb_ep *out;
198 unsigned long flags;
199
200 spin_lock_irqsave(&dev->lock, flags);
201 if (dev->port_usb)
202 out = dev->port_usb->out_ep;
203 else
204 out = NULL;
205 spin_unlock_irqrestore(&dev->lock, flags);
206
207 if (!out)
208 return -ENOTCONN;
209
210
211 /* Padding up to RX_EXTRA handles minor disagreements with host.
212 * Normally we use the USB "terminate on short read" convention;
213 * so allow up to (N*maxpacket), since that memory is normally
214 * already allocated. Some hardware doesn't deal well with short
215 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
216 * byte off the end (to force hardware errors on overflow).
217 *
218 * RNDIS uses internal framing, and explicitly allows senders to
219 * pad to end-of-packet. That's potentially nice for speed, but
220 * means receivers can't recover lost synch on their own (because
221 * new packets don't only start after a short RX).
222 */
223 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
224 size += dev->port_usb->header_len;
225 size += out->maxpacket - 1;
226 size -= size % out->maxpacket;
227
228 if (dev->port_usb->is_fixed)
229 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
230
231 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
232 if (skb == NULL) {
233 DBG(dev, "no rx skb\n");
234 goto enomem;
235 }
236
237 /* Some platforms perform better when IP packets are aligned,
238 * but on at least one, checksumming fails otherwise. Note:
239 * RNDIS headers involve variable numbers of LE32 values.
240 */
241 skb_reserve(skb, NET_IP_ALIGN);
242
243 req->buf = skb->data;
244 req->length = size;
245 req->complete = rx_complete;
246 req->context = skb;
247
248 retval = usb_ep_queue(out, req, gfp_flags);
249 if (retval == -ENOMEM)
250enomem:
251 defer_kevent(dev, WORK_RX_MEMORY);
252 if (retval) {
253 DBG(dev, "rx submit --> %d\n", retval);
254 if (skb)
255 dev_kfree_skb_any(skb);
256 spin_lock_irqsave(&dev->req_lock, flags);
257 list_add(&req->list, &dev->rx_reqs);
258 spin_unlock_irqrestore(&dev->req_lock, flags);
259 }
260 return retval;
261}
262
263static void rx_complete(struct usb_ep *ep, struct usb_request *req)
264{
265 struct sk_buff *skb = req->context, *skb2;
266 struct eth_dev *dev = ep->driver_data;
267 int status = req->status;
268
269 switch (status) {
270
271 /* normal completion */
272 case 0:
273 skb_put(skb, req->actual);
274
275 if (dev->unwrap) {
276 unsigned long flags;
277
278 spin_lock_irqsave(&dev->lock, flags);
279 if (dev->port_usb) {
280 status = dev->unwrap(dev->port_usb,
281 skb,
282 &dev->rx_frames);
283 } else {
284 dev_kfree_skb_any(skb);
285 status = -ENOTCONN;
286 }
287 spin_unlock_irqrestore(&dev->lock, flags);
288 } else {
289 skb_queue_tail(&dev->rx_frames, skb);
290 }
291 skb = NULL;
292
293 skb2 = skb_dequeue(&dev->rx_frames);
294 while (skb2) {
295 if (status < 0
296 || ETH_HLEN > skb2->len
297 || skb2->len > VLAN_ETH_FRAME_LEN) {
298 dev->net->stats.rx_errors++;
299 dev->net->stats.rx_length_errors++;
300 DBG(dev, "rx length %d\n", skb2->len);
301 dev_kfree_skb_any(skb2);
302 goto next_frame;
303 }
304 skb2->protocol = eth_type_trans(skb2, dev->net);
305 dev->net->stats.rx_packets++;
306 dev->net->stats.rx_bytes += skb2->len;
307
308 /* no buffer copies needed, unless hardware can't
309 * use skb buffers.
310 */
311 status = netif_rx(skb2);
312next_frame:
313 skb2 = skb_dequeue(&dev->rx_frames);
314 }
315 break;
316
317 /* software-driven interface shutdown */
318 case -ECONNRESET: /* unlink */
319 case -ESHUTDOWN: /* disconnect etc */
320 VDBG(dev, "rx shutdown, code %d\n", status);
321 goto quiesce;
322
323 /* for hardware automagic (such as pxa) */
324 case -ECONNABORTED: /* endpoint reset */
325 DBG(dev, "rx %s reset\n", ep->name);
326 defer_kevent(dev, WORK_RX_MEMORY);
327quiesce:
328 dev_kfree_skb_any(skb);
329 goto clean;
330
331 /* data overrun */
332 case -EOVERFLOW:
333 dev->net->stats.rx_over_errors++;
334 /* FALLTHROUGH */
335
336 default:
337 dev->net->stats.rx_errors++;
338 DBG(dev, "rx status %d\n", status);
339 break;
340 }
341
342 if (skb)
343 dev_kfree_skb_any(skb);
344 if (!netif_running(dev->net)) {
345clean:
346 spin_lock(&dev->req_lock);
347 list_add(&req->list, &dev->rx_reqs);
348 spin_unlock(&dev->req_lock);
349 req = NULL;
350 }
351 if (req)
352 rx_submit(dev, req, GFP_ATOMIC);
353}
354
355static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
356{
357 unsigned i;
358 struct usb_request *req;
359
360 if (!n)
361 return -ENOMEM;
362
363 /* queue/recycle up to N requests */
364 i = n;
365 list_for_each_entry(req, list, list) {
366 if (i-- == 0)
367 goto extra;
368 }
369 while (i--) {
370 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
371 if (!req)
372 return list_empty(list) ? -ENOMEM : 0;
373 list_add(&req->list, list);
374 }
375 return 0;
376
377extra:
378 /* free extras */
379 for (;;) {
380 struct list_head *next;
381
382 next = req->list.next;
383 list_del(&req->list);
384 usb_ep_free_request(ep, req);
385
386 if (next == list)
387 break;
388
389 req = container_of(next, struct usb_request, list);
390 }
391 return 0;
392}
393
394static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
395{
396 int status;
397
398 spin_lock(&dev->req_lock);
399 status = prealloc(&dev->tx_reqs, link->in_ep, n);
400 if (status < 0)
401 goto fail;
402 status = prealloc(&dev->rx_reqs, link->out_ep, n);
403 if (status < 0)
404 goto fail;
405 goto done;
406fail:
407 DBG(dev, "can't alloc requests\n");
408done:
409 spin_unlock(&dev->req_lock);
410 return status;
411}
412
413static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
414{
415 struct usb_request *req;
416 unsigned long flags;
417
418 /* fill unused rxq slots with some skb */
419 spin_lock_irqsave(&dev->req_lock, flags);
420 while (!list_empty(&dev->rx_reqs)) {
421 req = container_of(dev->rx_reqs.next,
422 struct usb_request, list);
423 list_del_init(&req->list);
424 spin_unlock_irqrestore(&dev->req_lock, flags);
425
426 if (rx_submit(dev, req, gfp_flags) < 0) {
427 defer_kevent(dev, WORK_RX_MEMORY);
428 return;
429 }
430
431 spin_lock_irqsave(&dev->req_lock, flags);
432 }
433 spin_unlock_irqrestore(&dev->req_lock, flags);
434}
435
436static void eth_work(struct work_struct *work)
437{
438 struct eth_dev *dev = container_of(work, struct eth_dev, work);
439
440 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
441 if (netif_running(dev->net))
442 rx_fill(dev, GFP_KERNEL);
443 }
444
445 if (dev->todo)
446 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
447}
448
449static void tx_complete(struct usb_ep *ep, struct usb_request *req)
450{
451 struct sk_buff *skb = req->context;
452 struct eth_dev *dev = ep->driver_data;
453
454 switch (req->status) {
455 default:
456 dev->net->stats.tx_errors++;
457 VDBG(dev, "tx err %d\n", req->status);
458 /* FALLTHROUGH */
459 case -ECONNRESET: /* unlink */
460 case -ESHUTDOWN: /* disconnect etc */
461 break;
462 case 0:
463 dev->net->stats.tx_bytes += skb->len;
464 }
465 dev->net->stats.tx_packets++;
466
467 spin_lock(&dev->req_lock);
468 list_add(&req->list, &dev->tx_reqs);
469 spin_unlock(&dev->req_lock);
470 dev_kfree_skb_any(skb);
471
472 atomic_dec(&dev->tx_qlen);
473 if (netif_carrier_ok(dev->net))
474 netif_wake_queue(dev->net);
475}
476
477static inline int is_promisc(u16 cdc_filter)
478{
479 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
480}
481
482static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
483 struct net_device *net)
484{
485 struct eth_dev *dev = netdev_priv(net);
486 int length = 0;
487 int retval;
488 struct usb_request *req = NULL;
489 unsigned long flags;
490 struct usb_ep *in;
491 u16 cdc_filter;
492
493 spin_lock_irqsave(&dev->lock, flags);
494 if (dev->port_usb) {
495 in = dev->port_usb->in_ep;
496 cdc_filter = dev->port_usb->cdc_filter;
497 } else {
498 in = NULL;
499 cdc_filter = 0;
500 }
501 spin_unlock_irqrestore(&dev->lock, flags);
502
503 if (skb && !in) {
504 dev_kfree_skb_any(skb);
505 return NETDEV_TX_OK;
506 }
507
508 /* apply outgoing CDC or RNDIS filters */
509 if (skb && !is_promisc(cdc_filter)) {
510 u8 *dest = skb->data;
511
512 if (is_multicast_ether_addr(dest)) {
513 u16 type;
514
515 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
516 * SET_ETHERNET_MULTICAST_FILTERS requests
517 */
518 if (is_broadcast_ether_addr(dest))
519 type = USB_CDC_PACKET_TYPE_BROADCAST;
520 else
521 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
522 if (!(cdc_filter & type)) {
523 dev_kfree_skb_any(skb);
524 return NETDEV_TX_OK;
525 }
526 }
527 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
528 }
529
530 spin_lock_irqsave(&dev->req_lock, flags);
531 /*
532 * this freelist can be empty if an interrupt triggered disconnect()
533 * and reconfigured the gadget (shutting down this queue) after the
534 * network stack decided to xmit but before we got the spinlock.
535 */
536 if (list_empty(&dev->tx_reqs)) {
537 spin_unlock_irqrestore(&dev->req_lock, flags);
538 return NETDEV_TX_BUSY;
539 }
540
541 req = container_of(dev->tx_reqs.next, struct usb_request, list);
542 list_del(&req->list);
543
544 /* temporarily stop TX queue when the freelist empties */
545 if (list_empty(&dev->tx_reqs))
546 netif_stop_queue(net);
547 spin_unlock_irqrestore(&dev->req_lock, flags);
548
549 /* no buffer copies needed, unless the network stack did it
550 * or the hardware can't use skb buffers.
551 * or there's not enough space for extra headers we need
552 */
553 if (dev->wrap) {
554 unsigned long flags;
555
556 spin_lock_irqsave(&dev->lock, flags);
557 if (dev->port_usb)
558 skb = dev->wrap(dev->port_usb, skb);
559 spin_unlock_irqrestore(&dev->lock, flags);
560 if (!skb) {
561 /* Multi frame CDC protocols may store the frame for
562 * later which is not a dropped frame.
563 */
564 if (dev->port_usb->supports_multi_frame)
565 goto multiframe;
566 goto drop;
567 }
568 }
569
570 length = skb->len;
571 req->buf = skb->data;
572 req->context = skb;
573 req->complete = tx_complete;
574
575 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
576 if (dev->port_usb->is_fixed &&
577 length == dev->port_usb->fixed_in_len &&
578 (length % in->maxpacket) == 0)
579 req->zero = 0;
580 else
581 req->zero = 1;
582
583 /* use zlp framing on tx for strict CDC-Ether conformance,
584 * though any robust network rx path ignores extra padding.
585 * and some hardware doesn't like to write zlps.
586 */
587 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
588 length++;
589
590 req->length = length;
591
592 /* throttle high/super speed IRQ rate back slightly */
593 if (gadget_is_dualspeed(dev->gadget))
594 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH ||
595 dev->gadget->speed == USB_SPEED_SUPER)
596 ? ((atomic_read(&dev->tx_qlen) % dev->qmult) != 0)
597 : 0;
598
599 retval = usb_ep_queue(in, req, GFP_ATOMIC);
600 switch (retval) {
601 default:
602 DBG(dev, "tx queue err %d\n", retval);
603 break;
604 case 0:
605 net->trans_start = jiffies;
606 atomic_inc(&dev->tx_qlen);
607 }
608
609 if (retval) {
610 dev_kfree_skb_any(skb);
611drop:
612 dev->net->stats.tx_dropped++;
613multiframe:
614 spin_lock_irqsave(&dev->req_lock, flags);
615 if (list_empty(&dev->tx_reqs))
616 netif_start_queue(net);
617 list_add(&req->list, &dev->tx_reqs);
618 spin_unlock_irqrestore(&dev->req_lock, flags);
619 }
620 return NETDEV_TX_OK;
621}
622
623/*-------------------------------------------------------------------------*/
624
625static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
626{
627 DBG(dev, "%s\n", __func__);
628
629 /* fill the rx queue */
630 rx_fill(dev, gfp_flags);
631
632 /* and open the tx floodgates */
633 atomic_set(&dev->tx_qlen, 0);
634 netif_wake_queue(dev->net);
635}
636
637static int eth_open(struct net_device *net)
638{
639 struct eth_dev *dev = netdev_priv(net);
640 struct gether *link;
641
642 DBG(dev, "%s\n", __func__);
643 if (netif_carrier_ok(dev->net))
644 eth_start(dev, GFP_KERNEL);
645
646 spin_lock_irq(&dev->lock);
647 link = dev->port_usb;
648 if (link && link->open)
649 link->open(link);
650 spin_unlock_irq(&dev->lock);
651
652 return 0;
653}
654
655static int eth_stop(struct net_device *net)
656{
657 struct eth_dev *dev = netdev_priv(net);
658 unsigned long flags;
659
660 VDBG(dev, "%s\n", __func__);
661 netif_stop_queue(net);
662
663 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
664 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
665 dev->net->stats.rx_errors, dev->net->stats.tx_errors
666 );
667
668 /* ensure there are no more active requests */
669 spin_lock_irqsave(&dev->lock, flags);
670 if (dev->port_usb) {
671 struct gether *link = dev->port_usb;
672 const struct usb_endpoint_descriptor *in;
673 const struct usb_endpoint_descriptor *out;
674
675 if (link->close)
676 link->close(link);
677
678 /* NOTE: we have no abort-queue primitive we could use
679 * to cancel all pending I/O. Instead, we disable then
680 * reenable the endpoints ... this idiom may leave toggle
681 * wrong, but that's a self-correcting error.
682 *
683 * REVISIT: we *COULD* just let the transfers complete at
684 * their own pace; the network stack can handle old packets.
685 * For the moment we leave this here, since it works.
686 */
687 in = link->in_ep->desc;
688 out = link->out_ep->desc;
689 usb_ep_disable(link->in_ep);
690 usb_ep_disable(link->out_ep);
691 if (netif_carrier_ok(net)) {
692 DBG(dev, "host still using in/out endpoints\n");
693 link->in_ep->desc = in;
694 link->out_ep->desc = out;
695 usb_ep_enable(link->in_ep);
696 usb_ep_enable(link->out_ep);
697 }
698 }
699 spin_unlock_irqrestore(&dev->lock, flags);
700
701 return 0;
702}
703
704/*-------------------------------------------------------------------------*/
705
706static int get_ether_addr(const char *str, u8 *dev_addr)
707{
708 if (str) {
709 unsigned i;
710
711 for (i = 0; i < 6; i++) {
712 unsigned char num;
713
714 if ((*str == '.') || (*str == ':'))
715 str++;
716 num = hex_to_bin(*str++) << 4;
717 num |= hex_to_bin(*str++);
718 dev_addr [i] = num;
719 }
720 if (is_valid_ether_addr(dev_addr))
721 return 0;
722 }
723 eth_random_addr(dev_addr);
724 return 1;
725}
726
727static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len)
728{
729 if (len < 18)
730 return -EINVAL;
731
732 snprintf(str, len, "%02x:%02x:%02x:%02x:%02x:%02x",
733 dev_addr[0], dev_addr[1], dev_addr[2],
734 dev_addr[3], dev_addr[4], dev_addr[5]);
735 return 18;
736}
737
738static const struct net_device_ops eth_netdev_ops = {
739 .ndo_open = eth_open,
740 .ndo_stop = eth_stop,
741 .ndo_start_xmit = eth_start_xmit,
742 .ndo_change_mtu = ueth_change_mtu,
743 .ndo_set_mac_address = eth_mac_addr,
744 .ndo_validate_addr = eth_validate_addr,
745};
746
747static struct device_type gadget_type = {
748 .name = "gadget",
749};
750
751/**
752 * gether_setup_name - initialize one ethernet-over-usb link
753 * @g: gadget to associated with these links
754 * @ethaddr: NULL, or a buffer in which the ethernet address of the
755 * host side of the link is recorded
756 * @netname: name for network device (for example, "usb")
757 * Context: may sleep
758 *
759 * This sets up the single network link that may be exported by a
760 * gadget driver using this framework. The link layer addresses are
761 * set up using module parameters.
762 *
763 * Returns an eth_dev pointer on success, or an ERR_PTR on failure.
764 */
765struct eth_dev *gether_setup_name(struct usb_gadget *g,
766 const char *dev_addr, const char *host_addr,
767 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname)
768{
769 struct eth_dev *dev;
770 struct net_device *net;
771 int status;
772
773 net = alloc_etherdev(sizeof *dev);
774 if (!net)
775 return ERR_PTR(-ENOMEM);
776
777 dev = netdev_priv(net);
778 spin_lock_init(&dev->lock);
779 spin_lock_init(&dev->req_lock);
780 INIT_WORK(&dev->work, eth_work);
781 INIT_LIST_HEAD(&dev->tx_reqs);
782 INIT_LIST_HEAD(&dev->rx_reqs);
783
784 skb_queue_head_init(&dev->rx_frames);
785
786 /* network device setup */
787 dev->net = net;
788 dev->qmult = qmult;
789 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
790
791 if (get_ether_addr(dev_addr, net->dev_addr))
792 dev_warn(&g->dev,
793 "using random %s ethernet address\n", "self");
794 if (get_ether_addr(host_addr, dev->host_mac))
795 dev_warn(&g->dev,
796 "using random %s ethernet address\n", "host");
797
798 if (ethaddr)
799 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
800
801 net->netdev_ops = &eth_netdev_ops;
802
803 net->ethtool_ops = &ops;
804
805 dev->gadget = g;
806 SET_NETDEV_DEV(net, &g->dev);
807 SET_NETDEV_DEVTYPE(net, &gadget_type);
808
809 status = register_netdev(net);
810 if (status < 0) {
811 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
812 free_netdev(net);
813 dev = ERR_PTR(status);
814 } else {
815 INFO(dev, "MAC %pM\n", net->dev_addr);
816 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
817
818 /*
819 * two kinds of host-initiated state changes:
820 * - iff DATA transfer is active, carrier is "on"
821 * - tx queueing enabled if open *and* carrier is "on"
822 */
823 netif_carrier_off(net);
824 }
825
826 return dev;
827}
828EXPORT_SYMBOL_GPL(gether_setup_name);
829
830struct net_device *gether_setup_name_default(const char *netname)
831{
832 struct net_device *net;
833 struct eth_dev *dev;
834
835 net = alloc_etherdev(sizeof(*dev));
836 if (!net)
837 return ERR_PTR(-ENOMEM);
838
839 dev = netdev_priv(net);
840 spin_lock_init(&dev->lock);
841 spin_lock_init(&dev->req_lock);
842 INIT_WORK(&dev->work, eth_work);
843 INIT_LIST_HEAD(&dev->tx_reqs);
844 INIT_LIST_HEAD(&dev->rx_reqs);
845
846 skb_queue_head_init(&dev->rx_frames);
847
848 /* network device setup */
849 dev->net = net;
850 dev->qmult = QMULT_DEFAULT;
851 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
852
853 eth_random_addr(dev->dev_mac);
854 pr_warn("using random %s ethernet address\n", "self");
855 eth_random_addr(dev->host_mac);
856 pr_warn("using random %s ethernet address\n", "host");
857
858 net->netdev_ops = &eth_netdev_ops;
859
860 net->ethtool_ops = &ops;
861 SET_NETDEV_DEVTYPE(net, &gadget_type);
862
863 return net;
864}
865EXPORT_SYMBOL_GPL(gether_setup_name_default);
866
867int gether_register_netdev(struct net_device *net)
868{
869 struct eth_dev *dev;
870 struct usb_gadget *g;
871 struct sockaddr sa;
872 int status;
873
874 if (!net->dev.parent)
875 return -EINVAL;
876 dev = netdev_priv(net);
877 g = dev->gadget;
878 status = register_netdev(net);
879 if (status < 0) {
880 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
881 return status;
882 } else {
883 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
884
885 /* two kinds of host-initiated state changes:
886 * - iff DATA transfer is active, carrier is "on"
887 * - tx queueing enabled if open *and* carrier is "on"
888 */
889 netif_carrier_off(net);
890 }
891 sa.sa_family = net->type;
892 memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN);
893 rtnl_lock();
894 status = dev_set_mac_address(net, &sa);
895 rtnl_unlock();
896 if (status)
897 pr_warn("cannot set self ethernet address: %d\n", status);
898 else
899 INFO(dev, "MAC %pM\n", dev->dev_mac);
900
901 return status;
902}
903EXPORT_SYMBOL_GPL(gether_register_netdev);
904
905void gether_set_gadget(struct net_device *net, struct usb_gadget *g)
906{
907 struct eth_dev *dev;
908
909 dev = netdev_priv(net);
910 dev->gadget = g;
911 SET_NETDEV_DEV(net, &g->dev);
912}
913EXPORT_SYMBOL_GPL(gether_set_gadget);
914
915int gether_set_dev_addr(struct net_device *net, const char *dev_addr)
916{
917 struct eth_dev *dev;
918 u8 new_addr[ETH_ALEN];
919
920 dev = netdev_priv(net);
921 if (get_ether_addr(dev_addr, new_addr))
922 return -EINVAL;
923 memcpy(dev->dev_mac, new_addr, ETH_ALEN);
924 return 0;
925}
926EXPORT_SYMBOL_GPL(gether_set_dev_addr);
927
928int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len)
929{
930 struct eth_dev *dev;
931
932 dev = netdev_priv(net);
933 return get_ether_addr_str(dev->dev_mac, dev_addr, len);
934}
935EXPORT_SYMBOL_GPL(gether_get_dev_addr);
936
937int gether_set_host_addr(struct net_device *net, const char *host_addr)
938{
939 struct eth_dev *dev;
940 u8 new_addr[ETH_ALEN];
941
942 dev = netdev_priv(net);
943 if (get_ether_addr(host_addr, new_addr))
944 return -EINVAL;
945 memcpy(dev->host_mac, new_addr, ETH_ALEN);
946 return 0;
947}
948EXPORT_SYMBOL_GPL(gether_set_host_addr);
949
950int gether_get_host_addr(struct net_device *net, char *host_addr, int len)
951{
952 struct eth_dev *dev;
953
954 dev = netdev_priv(net);
955 return get_ether_addr_str(dev->host_mac, host_addr, len);
956}
957EXPORT_SYMBOL_GPL(gether_get_host_addr);
958
959int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len)
960{
961 struct eth_dev *dev;
962
963 if (len < 13)
964 return -EINVAL;
965
966 dev = netdev_priv(net);
967 snprintf(host_addr, len, "%pm", dev->host_mac);
968
969 return strlen(host_addr);
970}
971EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc);
972
973void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN])
974{
975 struct eth_dev *dev;
976
977 dev = netdev_priv(net);
978 memcpy(host_mac, dev->host_mac, ETH_ALEN);
979}
980EXPORT_SYMBOL_GPL(gether_get_host_addr_u8);
981
982void gether_set_qmult(struct net_device *net, unsigned qmult)
983{
984 struct eth_dev *dev;
985
986 dev = netdev_priv(net);
987 dev->qmult = qmult;
988}
989EXPORT_SYMBOL_GPL(gether_set_qmult);
990
991unsigned gether_get_qmult(struct net_device *net)
992{
993 struct eth_dev *dev;
994
995 dev = netdev_priv(net);
996 return dev->qmult;
997}
998EXPORT_SYMBOL_GPL(gether_get_qmult);
999
1000int gether_get_ifname(struct net_device *net, char *name, int len)
1001{
1002 rtnl_lock();
1003 strlcpy(name, netdev_name(net), len);
1004 rtnl_unlock();
1005 return strlen(name);
1006}
1007EXPORT_SYMBOL_GPL(gether_get_ifname);
1008
1009/**
1010 * gether_cleanup - remove Ethernet-over-USB device
1011 * Context: may sleep
1012 *
1013 * This is called to free all resources allocated by @gether_setup().
1014 */
1015void gether_cleanup(struct eth_dev *dev)
1016{
1017 if (!dev)
1018 return;
1019
1020 unregister_netdev(dev->net);
1021 flush_work(&dev->work);
1022 free_netdev(dev->net);
1023}
1024EXPORT_SYMBOL_GPL(gether_cleanup);
1025
1026/**
1027 * gether_connect - notify network layer that USB link is active
1028 * @link: the USB link, set up with endpoints, descriptors matching
1029 * current device speed, and any framing wrapper(s) set up.
1030 * Context: irqs blocked
1031 *
1032 * This is called to activate endpoints and let the network layer know
1033 * the connection is active ("carrier detect"). It may cause the I/O
1034 * queues to open and start letting network packets flow, but will in
1035 * any case activate the endpoints so that they respond properly to the
1036 * USB host.
1037 *
1038 * Verify net_device pointer returned using IS_ERR(). If it doesn't
1039 * indicate some error code (negative errno), ep->driver_data values
1040 * have been overwritten.
1041 */
1042struct net_device *gether_connect(struct gether *link)
1043{
1044 struct eth_dev *dev = link->ioport;
1045 int result = 0;
1046
1047 if (!dev)
1048 return ERR_PTR(-EINVAL);
1049
1050 link->in_ep->driver_data = dev;
1051 result = usb_ep_enable(link->in_ep);
1052 if (result != 0) {
1053 DBG(dev, "enable %s --> %d\n",
1054 link->in_ep->name, result);
1055 goto fail0;
1056 }
1057
1058 link->out_ep->driver_data = dev;
1059 result = usb_ep_enable(link->out_ep);
1060 if (result != 0) {
1061 DBG(dev, "enable %s --> %d\n",
1062 link->out_ep->name, result);
1063 goto fail1;
1064 }
1065
1066 if (result == 0)
1067 result = alloc_requests(dev, link, qlen(dev->gadget,
1068 dev->qmult));
1069
1070 if (result == 0) {
1071 dev->zlp = link->is_zlp_ok;
1072 DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult));
1073
1074 dev->header_len = link->header_len;
1075 dev->unwrap = link->unwrap;
1076 dev->wrap = link->wrap;
1077
1078 spin_lock(&dev->lock);
1079 dev->port_usb = link;
1080 if (netif_running(dev->net)) {
1081 if (link->open)
1082 link->open(link);
1083 } else {
1084 if (link->close)
1085 link->close(link);
1086 }
1087 spin_unlock(&dev->lock);
1088
1089 netif_carrier_on(dev->net);
1090 if (netif_running(dev->net))
1091 eth_start(dev, GFP_ATOMIC);
1092
1093 /* on error, disable any endpoints */
1094 } else {
1095 (void) usb_ep_disable(link->out_ep);
1096fail1:
1097 (void) usb_ep_disable(link->in_ep);
1098 }
1099fail0:
1100 /* caller is responsible for cleanup on error */
1101 if (result < 0)
1102 return ERR_PTR(result);
1103 return dev->net;
1104}
1105EXPORT_SYMBOL_GPL(gether_connect);
1106
1107/**
1108 * gether_disconnect - notify network layer that USB link is inactive
1109 * @link: the USB link, on which gether_connect() was called
1110 * Context: irqs blocked
1111 *
1112 * This is called to deactivate endpoints and let the network layer know
1113 * the connection went inactive ("no carrier").
1114 *
1115 * On return, the state is as if gether_connect() had never been called.
1116 * The endpoints are inactive, and accordingly without active USB I/O.
1117 * Pointers to endpoint descriptors and endpoint private data are nulled.
1118 */
1119void gether_disconnect(struct gether *link)
1120{
1121 struct eth_dev *dev = link->ioport;
1122 struct usb_request *req;
1123
1124 WARN_ON(!dev);
1125 if (!dev)
1126 return;
1127
1128 DBG(dev, "%s\n", __func__);
1129
1130 netif_tx_lock(dev->net);
1131 netif_stop_queue(dev->net);
1132 netif_tx_unlock(dev->net);
1133
1134 netif_carrier_off(dev->net);
1135
1136 /* disable endpoints, forcing (synchronous) completion
1137 * of all pending i/o. then free the request objects
1138 * and forget about the endpoints.
1139 */
1140 usb_ep_disable(link->in_ep);
1141 spin_lock(&dev->req_lock);
1142 while (!list_empty(&dev->tx_reqs)) {
1143 req = container_of(dev->tx_reqs.next,
1144 struct usb_request, list);
1145 list_del(&req->list);
1146
1147 spin_unlock(&dev->req_lock);
1148 usb_ep_free_request(link->in_ep, req);
1149 spin_lock(&dev->req_lock);
1150 }
1151 spin_unlock(&dev->req_lock);
1152 link->in_ep->driver_data = NULL;
1153 link->in_ep->desc = NULL;
1154
1155 usb_ep_disable(link->out_ep);
1156 spin_lock(&dev->req_lock);
1157 while (!list_empty(&dev->rx_reqs)) {
1158 req = container_of(dev->rx_reqs.next,
1159 struct usb_request, list);
1160 list_del(&req->list);
1161
1162 spin_unlock(&dev->req_lock);
1163 usb_ep_free_request(link->out_ep, req);
1164 spin_lock(&dev->req_lock);
1165 }
1166 spin_unlock(&dev->req_lock);
1167 link->out_ep->driver_data = NULL;
1168 link->out_ep->desc = NULL;
1169
1170 /* finish forgetting about this USB link episode */
1171 dev->header_len = 0;
1172 dev->unwrap = NULL;
1173 dev->wrap = NULL;
1174
1175 spin_lock(&dev->lock);
1176 dev->port_usb = NULL;
1177 spin_unlock(&dev->lock);
1178}
1179EXPORT_SYMBOL_GPL(gether_disconnect);
1180
1181MODULE_LICENSE("GPL");
1182MODULE_AUTHOR("David Brownell");
generated by cgit v1.2.2 (git 2.25.0) at 2026-05-28 17:38:28 -0400