Loading...
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
4 *
5 * Copyright (C) 2003-2005,2008 David Brownell
6 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
7 * Copyright (C) 2008 Nokia Corporation
8 */
9
10/* #define VERBOSE_DEBUG */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/gfp.h>
15#include <linux/device.h>
16#include <linux/ctype.h>
17#include <linux/etherdevice.h>
18#include <linux/ethtool.h>
19#include <linux/if_vlan.h>
20#include <linux/string_helpers.h>
21#include <linux/usb/composite.h>
22
23#include "u_ether.h"
24
25
26/*
27 * This component encapsulates the Ethernet link glue needed to provide
28 * one (!) network link through the USB gadget stack, normally "usb0".
29 *
30 * The control and data models are handled by the function driver which
31 * connects to this code; such as CDC Ethernet (ECM or EEM),
32 * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
33 * management.
34 *
35 * Link level addressing is handled by this component using module
36 * parameters; if no such parameters are provided, random link level
37 * addresses are used. Each end of the link uses one address. The
38 * host end address is exported in various ways, and is often recorded
39 * in configuration databases.
40 *
41 * The driver which assembles each configuration using such a link is
42 * responsible for ensuring that each configuration includes at most one
43 * instance of is network link. (The network layer provides ways for
44 * this single "physical" link to be used by multiple virtual links.)
45 */
46
47#define UETH__VERSION "29-May-2008"
48
49/* Experiments show that both Linux and Windows hosts allow up to 16k
50 * frame sizes. Set the max MTU size to 15k+52 to prevent allocating 32k
51 * blocks and still have efficient handling. */
52#define GETHER_MAX_MTU_SIZE 15412
53#define GETHER_MAX_ETH_FRAME_LEN (GETHER_MAX_MTU_SIZE + ETH_HLEN)
54
55struct eth_dev {
56 /* lock is held while accessing port_usb
57 */
58 spinlock_t lock;
59 struct gether *port_usb;
60
61 struct net_device *net;
62 struct usb_gadget *gadget;
63
64 spinlock_t req_lock; /* guard {rx,tx}_reqs */
65 struct list_head tx_reqs, rx_reqs;
66 atomic_t tx_qlen;
67
68 struct sk_buff_head rx_frames;
69
70 unsigned qmult;
71
72 unsigned header_len;
73 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
74 int (*unwrap)(struct gether *,
75 struct sk_buff *skb,
76 struct sk_buff_head *list);
77
78 struct work_struct work;
79
80 unsigned long todo;
81#define WORK_RX_MEMORY 0
82
83 bool zlp;
84 bool no_skb_reserve;
85 bool ifname_set;
86 u8 host_mac[ETH_ALEN];
87 u8 dev_mac[ETH_ALEN];
88};
89
90/*-------------------------------------------------------------------------*/
91
92#define RX_EXTRA 20 /* bytes guarding against rx overflows */
93
94#define DEFAULT_QLEN 2 /* double buffering by default */
95
96/* use deeper queues at high/super speed */
97static inline int qlen(struct usb_gadget *gadget, unsigned qmult)
98{
99 if (gadget->speed == USB_SPEED_HIGH || gadget->speed >= USB_SPEED_SUPER)
100 return qmult * DEFAULT_QLEN;
101 else
102 return DEFAULT_QLEN;
103}
104
105/*-------------------------------------------------------------------------*/
106
107/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
108
109static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
110{
111 struct eth_dev *dev = netdev_priv(net);
112
113 strscpy(p->driver, "g_ether", sizeof(p->driver));
114 strscpy(p->version, UETH__VERSION, sizeof(p->version));
115 strscpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version));
116 strscpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info));
117}
118
119/* REVISIT can also support:
120 * - WOL (by tracking suspends and issuing remote wakeup)
121 * - msglevel (implies updated messaging)
122 * - ... probably more ethtool ops
123 */
124
125static const struct ethtool_ops ops = {
126 .get_drvinfo = eth_get_drvinfo,
127 .get_link = ethtool_op_get_link,
128};
129
130static void defer_kevent(struct eth_dev *dev, int flag)
131{
132 if (test_and_set_bit(flag, &dev->todo))
133 return;
134 if (!schedule_work(&dev->work))
135 ERROR(dev, "kevent %d may have been dropped\n", flag);
136 else
137 DBG(dev, "kevent %d scheduled\n", flag);
138}
139
140static void rx_complete(struct usb_ep *ep, struct usb_request *req);
141
142static int
143rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
144{
145 struct usb_gadget *g = dev->gadget;
146 struct sk_buff *skb;
147 int retval = -ENOMEM;
148 size_t size = 0;
149 struct usb_ep *out;
150 unsigned long flags;
151
152 spin_lock_irqsave(&dev->lock, flags);
153 if (dev->port_usb)
154 out = dev->port_usb->out_ep;
155 else
156 out = NULL;
157
158 if (!out)
159 {
160 spin_unlock_irqrestore(&dev->lock, flags);
161 return -ENOTCONN;
162 }
163
164 /* Padding up to RX_EXTRA handles minor disagreements with host.
165 * Normally we use the USB "terminate on short read" convention;
166 * so allow up to (N*maxpacket), since that memory is normally
167 * already allocated. Some hardware doesn't deal well with short
168 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
169 * byte off the end (to force hardware errors on overflow).
170 *
171 * RNDIS uses internal framing, and explicitly allows senders to
172 * pad to end-of-packet. That's potentially nice for speed, but
173 * means receivers can't recover lost synch on their own (because
174 * new packets don't only start after a short RX).
175 */
176 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
177 size += dev->port_usb->header_len;
178
179 if (g->quirk_ep_out_aligned_size) {
180 size += out->maxpacket - 1;
181 size -= size % out->maxpacket;
182 }
183
184 if (dev->port_usb->is_fixed)
185 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
186 spin_unlock_irqrestore(&dev->lock, flags);
187
188 skb = __netdev_alloc_skb(dev->net, size + NET_IP_ALIGN, gfp_flags);
189 if (skb == NULL) {
190 DBG(dev, "no rx skb\n");
191 goto enomem;
192 }
193
194 /* Some platforms perform better when IP packets are aligned,
195 * but on at least one, checksumming fails otherwise. Note:
196 * RNDIS headers involve variable numbers of LE32 values.
197 */
198 if (likely(!dev->no_skb_reserve))
199 skb_reserve(skb, NET_IP_ALIGN);
200
201 req->buf = skb->data;
202 req->length = size;
203 req->complete = rx_complete;
204 req->context = skb;
205
206 retval = usb_ep_queue(out, req, gfp_flags);
207 if (retval == -ENOMEM)
208enomem:
209 defer_kevent(dev, WORK_RX_MEMORY);
210 if (retval) {
211 DBG(dev, "rx submit --> %d\n", retval);
212 if (skb)
213 dev_kfree_skb_any(skb);
214 spin_lock_irqsave(&dev->req_lock, flags);
215 list_add(&req->list, &dev->rx_reqs);
216 spin_unlock_irqrestore(&dev->req_lock, flags);
217 }
218 return retval;
219}
220
221static void rx_complete(struct usb_ep *ep, struct usb_request *req)
222{
223 struct sk_buff *skb = req->context, *skb2;
224 struct eth_dev *dev = ep->driver_data;
225 int status = req->status;
226
227 switch (status) {
228
229 /* normal completion */
230 case 0:
231 skb_put(skb, req->actual);
232
233 if (dev->unwrap) {
234 unsigned long flags;
235
236 spin_lock_irqsave(&dev->lock, flags);
237 if (dev->port_usb) {
238 status = dev->unwrap(dev->port_usb,
239 skb,
240 &dev->rx_frames);
241 } else {
242 dev_kfree_skb_any(skb);
243 status = -ENOTCONN;
244 }
245 spin_unlock_irqrestore(&dev->lock, flags);
246 } else {
247 skb_queue_tail(&dev->rx_frames, skb);
248 }
249 skb = NULL;
250
251 skb2 = skb_dequeue(&dev->rx_frames);
252 while (skb2) {
253 if (status < 0
254 || ETH_HLEN > skb2->len
255 || skb2->len > GETHER_MAX_ETH_FRAME_LEN) {
256 dev->net->stats.rx_errors++;
257 dev->net->stats.rx_length_errors++;
258 DBG(dev, "rx length %d\n", skb2->len);
259 dev_kfree_skb_any(skb2);
260 goto next_frame;
261 }
262 skb2->protocol = eth_type_trans(skb2, dev->net);
263 dev->net->stats.rx_packets++;
264 dev->net->stats.rx_bytes += skb2->len;
265
266 /* no buffer copies needed, unless hardware can't
267 * use skb buffers.
268 */
269 status = netif_rx(skb2);
270next_frame:
271 skb2 = skb_dequeue(&dev->rx_frames);
272 }
273 break;
274
275 /* software-driven interface shutdown */
276 case -ECONNRESET: /* unlink */
277 case -ESHUTDOWN: /* disconnect etc */
278 VDBG(dev, "rx shutdown, code %d\n", status);
279 goto quiesce;
280
281 /* for hardware automagic (such as pxa) */
282 case -ECONNABORTED: /* endpoint reset */
283 DBG(dev, "rx %s reset\n", ep->name);
284 defer_kevent(dev, WORK_RX_MEMORY);
285quiesce:
286 dev_kfree_skb_any(skb);
287 goto clean;
288
289 /* data overrun */
290 case -EOVERFLOW:
291 dev->net->stats.rx_over_errors++;
292 fallthrough;
293
294 default:
295 dev->net->stats.rx_errors++;
296 DBG(dev, "rx status %d\n", status);
297 break;
298 }
299
300 if (skb)
301 dev_kfree_skb_any(skb);
302 if (!netif_running(dev->net)) {
303clean:
304 spin_lock(&dev->req_lock);
305 list_add(&req->list, &dev->rx_reqs);
306 spin_unlock(&dev->req_lock);
307 req = NULL;
308 }
309 if (req)
310 rx_submit(dev, req, GFP_ATOMIC);
311}
312
313static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
314{
315 unsigned i;
316 struct usb_request *req;
317
318 if (!n)
319 return -ENOMEM;
320
321 /* queue/recycle up to N requests */
322 i = n;
323 list_for_each_entry(req, list, list) {
324 if (i-- == 0)
325 goto extra;
326 }
327 while (i--) {
328 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
329 if (!req)
330 return list_empty(list) ? -ENOMEM : 0;
331 list_add(&req->list, list);
332 }
333 return 0;
334
335extra:
336 /* free extras */
337 for (;;) {
338 struct list_head *next;
339
340 next = req->list.next;
341 list_del(&req->list);
342 usb_ep_free_request(ep, req);
343
344 if (next == list)
345 break;
346
347 req = container_of(next, struct usb_request, list);
348 }
349 return 0;
350}
351
352static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
353{
354 int status;
355
356 spin_lock(&dev->req_lock);
357 status = prealloc(&dev->tx_reqs, link->in_ep, n);
358 if (status < 0)
359 goto fail;
360 status = prealloc(&dev->rx_reqs, link->out_ep, n);
361 if (status < 0)
362 goto fail;
363 goto done;
364fail:
365 DBG(dev, "can't alloc requests\n");
366done:
367 spin_unlock(&dev->req_lock);
368 return status;
369}
370
371static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
372{
373 struct usb_request *req;
374 unsigned long flags;
375
376 /* fill unused rxq slots with some skb */
377 spin_lock_irqsave(&dev->req_lock, flags);
378 while (!list_empty(&dev->rx_reqs)) {
379 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
380 list_del_init(&req->list);
381 spin_unlock_irqrestore(&dev->req_lock, flags);
382
383 if (rx_submit(dev, req, gfp_flags) < 0) {
384 defer_kevent(dev, WORK_RX_MEMORY);
385 return;
386 }
387
388 spin_lock_irqsave(&dev->req_lock, flags);
389 }
390 spin_unlock_irqrestore(&dev->req_lock, flags);
391}
392
393static void eth_work(struct work_struct *work)
394{
395 struct eth_dev *dev = container_of(work, struct eth_dev, work);
396
397 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
398 if (netif_running(dev->net))
399 rx_fill(dev, GFP_KERNEL);
400 }
401
402 if (dev->todo)
403 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
404}
405
406static void tx_complete(struct usb_ep *ep, struct usb_request *req)
407{
408 struct sk_buff *skb = req->context;
409 struct eth_dev *dev = ep->driver_data;
410
411 switch (req->status) {
412 default:
413 dev->net->stats.tx_errors++;
414 VDBG(dev, "tx err %d\n", req->status);
415 fallthrough;
416 case -ECONNRESET: /* unlink */
417 case -ESHUTDOWN: /* disconnect etc */
418 dev_kfree_skb_any(skb);
419 break;
420 case 0:
421 dev->net->stats.tx_bytes += skb->len;
422 dev_consume_skb_any(skb);
423 }
424 dev->net->stats.tx_packets++;
425
426 spin_lock(&dev->req_lock);
427 list_add(&req->list, &dev->tx_reqs);
428 spin_unlock(&dev->req_lock);
429
430 atomic_dec(&dev->tx_qlen);
431 if (netif_carrier_ok(dev->net))
432 netif_wake_queue(dev->net);
433}
434
435static inline int is_promisc(u16 cdc_filter)
436{
437 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
438}
439
440static int ether_wakeup_host(struct gether *port)
441{
442 int ret;
443 struct usb_function *func = &port->func;
444 struct usb_gadget *gadget = func->config->cdev->gadget;
445
446 if (func->func_suspended)
447 ret = usb_func_wakeup(func);
448 else
449 ret = usb_gadget_wakeup(gadget);
450
451 return ret;
452}
453
454static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
455 struct net_device *net)
456{
457 struct eth_dev *dev = netdev_priv(net);
458 int length = 0;
459 int retval;
460 struct usb_request *req = NULL;
461 unsigned long flags;
462 struct usb_ep *in;
463 u16 cdc_filter;
464
465 spin_lock_irqsave(&dev->lock, flags);
466 if (dev->port_usb) {
467 in = dev->port_usb->in_ep;
468 cdc_filter = dev->port_usb->cdc_filter;
469 } else {
470 in = NULL;
471 cdc_filter = 0;
472 }
473
474 if (dev->port_usb && dev->port_usb->is_suspend) {
475 DBG(dev, "Port suspended. Triggering wakeup\n");
476 netif_stop_queue(net);
477 spin_unlock_irqrestore(&dev->lock, flags);
478 ether_wakeup_host(dev->port_usb);
479 return NETDEV_TX_BUSY;
480 }
481
482 spin_unlock_irqrestore(&dev->lock, flags);
483
484 if (!in) {
485 if (skb)
486 dev_kfree_skb_any(skb);
487 return NETDEV_TX_OK;
488 }
489
490 /* apply outgoing CDC or RNDIS filters */
491 if (skb && !is_promisc(cdc_filter)) {
492 u8 *dest = skb->data;
493
494 if (is_multicast_ether_addr(dest)) {
495 u16 type;
496
497 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
498 * SET_ETHERNET_MULTICAST_FILTERS requests
499 */
500 if (is_broadcast_ether_addr(dest))
501 type = USB_CDC_PACKET_TYPE_BROADCAST;
502 else
503 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
504 if (!(cdc_filter & type)) {
505 dev_kfree_skb_any(skb);
506 return NETDEV_TX_OK;
507 }
508 }
509 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
510 }
511
512 spin_lock_irqsave(&dev->req_lock, flags);
513 /*
514 * this freelist can be empty if an interrupt triggered disconnect()
515 * and reconfigured the gadget (shutting down this queue) after the
516 * network stack decided to xmit but before we got the spinlock.
517 */
518 if (list_empty(&dev->tx_reqs)) {
519 spin_unlock_irqrestore(&dev->req_lock, flags);
520 return NETDEV_TX_BUSY;
521 }
522
523 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
524 list_del(&req->list);
525
526 /* temporarily stop TX queue when the freelist empties */
527 if (list_empty(&dev->tx_reqs))
528 netif_stop_queue(net);
529 spin_unlock_irqrestore(&dev->req_lock, flags);
530
531 /* no buffer copies needed, unless the network stack did it
532 * or the hardware can't use skb buffers.
533 * or there's not enough space for extra headers we need
534 */
535 if (dev->wrap) {
536 unsigned long flags;
537
538 spin_lock_irqsave(&dev->lock, flags);
539 if (dev->port_usb)
540 skb = dev->wrap(dev->port_usb, skb);
541 spin_unlock_irqrestore(&dev->lock, flags);
542 if (!skb) {
543 /* Multi frame CDC protocols may store the frame for
544 * later which is not a dropped frame.
545 */
546 if (dev->port_usb &&
547 dev->port_usb->supports_multi_frame)
548 goto multiframe;
549 goto drop;
550 }
551 }
552
553 length = skb->len;
554 req->buf = skb->data;
555 req->context = skb;
556 req->complete = tx_complete;
557
558 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
559 if (dev->port_usb &&
560 dev->port_usb->is_fixed &&
561 length == dev->port_usb->fixed_in_len &&
562 (length % in->maxpacket) == 0)
563 req->zero = 0;
564 else
565 req->zero = 1;
566
567 /* use zlp framing on tx for strict CDC-Ether conformance,
568 * though any robust network rx path ignores extra padding.
569 * and some hardware doesn't like to write zlps.
570 */
571 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
572 length++;
573
574 req->length = length;
575
576 retval = usb_ep_queue(in, req, GFP_ATOMIC);
577 switch (retval) {
578 default:
579 DBG(dev, "tx queue err %d\n", retval);
580 break;
581 case 0:
582 netif_trans_update(net);
583 atomic_inc(&dev->tx_qlen);
584 }
585
586 if (retval) {
587 dev_kfree_skb_any(skb);
588drop:
589 dev->net->stats.tx_dropped++;
590multiframe:
591 spin_lock_irqsave(&dev->req_lock, flags);
592 if (list_empty(&dev->tx_reqs))
593 netif_start_queue(net);
594 list_add(&req->list, &dev->tx_reqs);
595 spin_unlock_irqrestore(&dev->req_lock, flags);
596 }
597 return NETDEV_TX_OK;
598}
599
600/*-------------------------------------------------------------------------*/
601
602static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
603{
604 DBG(dev, "%s\n", __func__);
605
606 /* fill the rx queue */
607 rx_fill(dev, gfp_flags);
608
609 /* and open the tx floodgates */
610 atomic_set(&dev->tx_qlen, 0);
611 netif_wake_queue(dev->net);
612}
613
614static int eth_open(struct net_device *net)
615{
616 struct eth_dev *dev = netdev_priv(net);
617 struct gether *link;
618
619 DBG(dev, "%s\n", __func__);
620 if (netif_carrier_ok(dev->net))
621 eth_start(dev, GFP_KERNEL);
622
623 spin_lock_irq(&dev->lock);
624 link = dev->port_usb;
625 if (link && link->open)
626 link->open(link);
627 spin_unlock_irq(&dev->lock);
628
629 return 0;
630}
631
632static int eth_stop(struct net_device *net)
633{
634 struct eth_dev *dev = netdev_priv(net);
635 unsigned long flags;
636
637 VDBG(dev, "%s\n", __func__);
638 netif_stop_queue(net);
639
640 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
641 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
642 dev->net->stats.rx_errors, dev->net->stats.tx_errors
643 );
644
645 /* ensure there are no more active requests */
646 spin_lock_irqsave(&dev->lock, flags);
647 if (dev->port_usb) {
648 struct gether *link = dev->port_usb;
649 const struct usb_endpoint_descriptor *in;
650 const struct usb_endpoint_descriptor *out;
651
652 if (link->close)
653 link->close(link);
654
655 /* NOTE: we have no abort-queue primitive we could use
656 * to cancel all pending I/O. Instead, we disable then
657 * reenable the endpoints ... this idiom may leave toggle
658 * wrong, but that's a self-correcting error.
659 *
660 * REVISIT: we *COULD* just let the transfers complete at
661 * their own pace; the network stack can handle old packets.
662 * For the moment we leave this here, since it works.
663 */
664 in = link->in_ep->desc;
665 out = link->out_ep->desc;
666 usb_ep_disable(link->in_ep);
667 usb_ep_disable(link->out_ep);
668 if (netif_carrier_ok(net)) {
669 DBG(dev, "host still using in/out endpoints\n");
670 link->in_ep->desc = in;
671 link->out_ep->desc = out;
672 usb_ep_enable(link->in_ep);
673 usb_ep_enable(link->out_ep);
674 }
675 }
676 spin_unlock_irqrestore(&dev->lock, flags);
677
678 return 0;
679}
680
681/*-------------------------------------------------------------------------*/
682
683static int get_ether_addr(const char *str, u8 *dev_addr)
684{
685 if (str) {
686 unsigned i;
687
688 for (i = 0; i < 6; i++) {
689 unsigned char num;
690
691 if ((*str == '.') || (*str == ':'))
692 str++;
693 num = hex_to_bin(*str++) << 4;
694 num |= hex_to_bin(*str++);
695 dev_addr [i] = num;
696 }
697 if (is_valid_ether_addr(dev_addr))
698 return 0;
699 }
700 eth_random_addr(dev_addr);
701 return 1;
702}
703
704static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len)
705{
706 if (len < 18)
707 return -EINVAL;
708
709 snprintf(str, len, "%pM", dev_addr);
710 return 18;
711}
712
713static const struct net_device_ops eth_netdev_ops = {
714 .ndo_open = eth_open,
715 .ndo_stop = eth_stop,
716 .ndo_start_xmit = eth_start_xmit,
717 .ndo_set_mac_address = eth_mac_addr,
718 .ndo_validate_addr = eth_validate_addr,
719};
720
721static struct device_type gadget_type = {
722 .name = "gadget",
723};
724
725/*
726 * gether_setup_name - initialize one ethernet-over-usb link
727 * @g: gadget to associated with these links
728 * @ethaddr: NULL, or a buffer in which the ethernet address of the
729 * host side of the link is recorded
730 * @netname: name for network device (for example, "usb")
731 * Context: may sleep
732 *
733 * This sets up the single network link that may be exported by a
734 * gadget driver using this framework. The link layer addresses are
735 * set up using module parameters.
736 *
737 * Returns an eth_dev pointer on success, or an ERR_PTR on failure.
738 */
739struct eth_dev *gether_setup_name(struct usb_gadget *g,
740 const char *dev_addr, const char *host_addr,
741 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname)
742{
743 struct eth_dev *dev;
744 struct net_device *net;
745 int status;
746 u8 addr[ETH_ALEN];
747
748 net = alloc_etherdev(sizeof *dev);
749 if (!net)
750 return ERR_PTR(-ENOMEM);
751
752 dev = netdev_priv(net);
753 spin_lock_init(&dev->lock);
754 spin_lock_init(&dev->req_lock);
755 INIT_WORK(&dev->work, eth_work);
756 INIT_LIST_HEAD(&dev->tx_reqs);
757 INIT_LIST_HEAD(&dev->rx_reqs);
758
759 skb_queue_head_init(&dev->rx_frames);
760
761 /* network device setup */
762 dev->net = net;
763 dev->qmult = qmult;
764 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
765
766 if (get_ether_addr(dev_addr, addr)) {
767 net->addr_assign_type = NET_ADDR_RANDOM;
768 dev_warn(&g->dev,
769 "using random %s ethernet address\n", "self");
770 } else {
771 net->addr_assign_type = NET_ADDR_SET;
772 }
773 eth_hw_addr_set(net, addr);
774 if (get_ether_addr(host_addr, dev->host_mac))
775 dev_warn(&g->dev,
776 "using random %s ethernet address\n", "host");
777
778 if (ethaddr)
779 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
780
781 net->netdev_ops = ð_netdev_ops;
782
783 net->ethtool_ops = &ops;
784
785 /* MTU range: 14 - 15412 */
786 net->min_mtu = ETH_HLEN;
787 net->max_mtu = GETHER_MAX_MTU_SIZE;
788
789 dev->gadget = g;
790 SET_NETDEV_DEV(net, &g->dev);
791 SET_NETDEV_DEVTYPE(net, &gadget_type);
792
793 status = register_netdev(net);
794 if (status < 0) {
795 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
796 free_netdev(net);
797 dev = ERR_PTR(status);
798 } else {
799 INFO(dev, "MAC %pM\n", net->dev_addr);
800 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
801
802 /*
803 * two kinds of host-initiated state changes:
804 * - iff DATA transfer is active, carrier is "on"
805 * - tx queueing enabled if open *and* carrier is "on"
806 */
807 netif_carrier_off(net);
808 }
809
810 return dev;
811}
812EXPORT_SYMBOL_GPL(gether_setup_name);
813
814struct net_device *gether_setup_name_default(const char *netname)
815{
816 struct net_device *net;
817 struct eth_dev *dev;
818
819 net = alloc_etherdev(sizeof(*dev));
820 if (!net)
821 return ERR_PTR(-ENOMEM);
822
823 dev = netdev_priv(net);
824 spin_lock_init(&dev->lock);
825 spin_lock_init(&dev->req_lock);
826 INIT_WORK(&dev->work, eth_work);
827 INIT_LIST_HEAD(&dev->tx_reqs);
828 INIT_LIST_HEAD(&dev->rx_reqs);
829
830 skb_queue_head_init(&dev->rx_frames);
831
832 /* network device setup */
833 dev->net = net;
834 dev->qmult = QMULT_DEFAULT;
835 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
836
837 eth_random_addr(dev->dev_mac);
838
839 /* by default we always have a random MAC address */
840 net->addr_assign_type = NET_ADDR_RANDOM;
841
842 eth_random_addr(dev->host_mac);
843
844 net->netdev_ops = ð_netdev_ops;
845
846 net->ethtool_ops = &ops;
847 SET_NETDEV_DEVTYPE(net, &gadget_type);
848
849 /* MTU range: 14 - 15412 */
850 net->min_mtu = ETH_HLEN;
851 net->max_mtu = GETHER_MAX_MTU_SIZE;
852
853 return net;
854}
855EXPORT_SYMBOL_GPL(gether_setup_name_default);
856
857int gether_register_netdev(struct net_device *net)
858{
859 struct eth_dev *dev;
860 struct usb_gadget *g;
861 int status;
862
863 if (!net->dev.parent)
864 return -EINVAL;
865 dev = netdev_priv(net);
866 g = dev->gadget;
867
868 eth_hw_addr_set(net, dev->dev_mac);
869
870 status = register_netdev(net);
871 if (status < 0) {
872 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
873 return status;
874 } else {
875 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
876 INFO(dev, "MAC %pM\n", dev->dev_mac);
877
878 /* two kinds of host-initiated state changes:
879 * - iff DATA transfer is active, carrier is "on"
880 * - tx queueing enabled if open *and* carrier is "on"
881 */
882 netif_carrier_off(net);
883 }
884
885 return status;
886}
887EXPORT_SYMBOL_GPL(gether_register_netdev);
888
889void gether_set_gadget(struct net_device *net, struct usb_gadget *g)
890{
891 struct eth_dev *dev;
892
893 dev = netdev_priv(net);
894 dev->gadget = g;
895 SET_NETDEV_DEV(net, &g->dev);
896}
897EXPORT_SYMBOL_GPL(gether_set_gadget);
898
899int gether_set_dev_addr(struct net_device *net, const char *dev_addr)
900{
901 struct eth_dev *dev;
902 u8 new_addr[ETH_ALEN];
903
904 dev = netdev_priv(net);
905 if (get_ether_addr(dev_addr, new_addr))
906 return -EINVAL;
907 memcpy(dev->dev_mac, new_addr, ETH_ALEN);
908 net->addr_assign_type = NET_ADDR_SET;
909 return 0;
910}
911EXPORT_SYMBOL_GPL(gether_set_dev_addr);
912
913int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len)
914{
915 struct eth_dev *dev;
916 int ret;
917
918 dev = netdev_priv(net);
919 ret = get_ether_addr_str(dev->dev_mac, dev_addr, len);
920 if (ret + 1 < len) {
921 dev_addr[ret++] = '\n';
922 dev_addr[ret] = '\0';
923 }
924
925 return ret;
926}
927EXPORT_SYMBOL_GPL(gether_get_dev_addr);
928
929int gether_set_host_addr(struct net_device *net, const char *host_addr)
930{
931 struct eth_dev *dev;
932 u8 new_addr[ETH_ALEN];
933
934 dev = netdev_priv(net);
935 if (get_ether_addr(host_addr, new_addr))
936 return -EINVAL;
937 memcpy(dev->host_mac, new_addr, ETH_ALEN);
938 return 0;
939}
940EXPORT_SYMBOL_GPL(gether_set_host_addr);
941
942int gether_get_host_addr(struct net_device *net, char *host_addr, int len)
943{
944 struct eth_dev *dev;
945 int ret;
946
947 dev = netdev_priv(net);
948 ret = get_ether_addr_str(dev->host_mac, host_addr, len);
949 if (ret + 1 < len) {
950 host_addr[ret++] = '\n';
951 host_addr[ret] = '\0';
952 }
953
954 return ret;
955}
956EXPORT_SYMBOL_GPL(gether_get_host_addr);
957
958int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len)
959{
960 struct eth_dev *dev;
961
962 if (len < 13)
963 return -EINVAL;
964
965 dev = netdev_priv(net);
966 snprintf(host_addr, len, "%pm", dev->host_mac);
967
968 string_upper(host_addr, host_addr);
969
970 return strlen(host_addr);
971}
972EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc);
973
974void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN])
975{
976 struct eth_dev *dev;
977
978 dev = netdev_priv(net);
979 memcpy(host_mac, dev->host_mac, ETH_ALEN);
980}
981EXPORT_SYMBOL_GPL(gether_get_host_addr_u8);
982
983void gether_set_qmult(struct net_device *net, unsigned qmult)
984{
985 struct eth_dev *dev;
986
987 dev = netdev_priv(net);
988 dev->qmult = qmult;
989}
990EXPORT_SYMBOL_GPL(gether_set_qmult);
991
992unsigned gether_get_qmult(struct net_device *net)
993{
994 struct eth_dev *dev;
995
996 dev = netdev_priv(net);
997 return dev->qmult;
998}
999EXPORT_SYMBOL_GPL(gether_get_qmult);
1000
1001int gether_get_ifname(struct net_device *net, char *name, int len)
1002{
1003 struct eth_dev *dev = netdev_priv(net);
1004 int ret;
1005
1006 rtnl_lock();
1007 ret = scnprintf(name, len, "%s\n",
1008 dev->ifname_set ? net->name : netdev_name(net));
1009 rtnl_unlock();
1010 return ret;
1011}
1012EXPORT_SYMBOL_GPL(gether_get_ifname);
1013
1014int gether_set_ifname(struct net_device *net, const char *name, int len)
1015{
1016 struct eth_dev *dev = netdev_priv(net);
1017 char tmp[IFNAMSIZ];
1018 const char *p;
1019
1020 if (name[len - 1] == '\n')
1021 len--;
1022
1023 if (len >= sizeof(tmp))
1024 return -E2BIG;
1025
1026 strscpy(tmp, name, len + 1);
1027 if (!dev_valid_name(tmp))
1028 return -EINVAL;
1029
1030 /* Require exactly one %d, so binding will not fail with EEXIST. */
1031 p = strchr(name, '%');
1032 if (!p || p[1] != 'd' || strchr(p + 2, '%'))
1033 return -EINVAL;
1034
1035 strncpy(net->name, tmp, sizeof(net->name));
1036 dev->ifname_set = true;
1037
1038 return 0;
1039}
1040EXPORT_SYMBOL_GPL(gether_set_ifname);
1041
1042void gether_suspend(struct gether *link)
1043{
1044 struct eth_dev *dev = link->ioport;
1045 unsigned long flags;
1046
1047 if (!dev)
1048 return;
1049
1050 if (atomic_read(&dev->tx_qlen)) {
1051 /*
1052 * There is a transfer in progress. So we trigger a remote
1053 * wakeup to inform the host.
1054 */
1055 ether_wakeup_host(dev->port_usb);
1056 return;
1057 }
1058 spin_lock_irqsave(&dev->lock, flags);
1059 link->is_suspend = true;
1060 spin_unlock_irqrestore(&dev->lock, flags);
1061}
1062EXPORT_SYMBOL_GPL(gether_suspend);
1063
1064void gether_resume(struct gether *link)
1065{
1066 struct eth_dev *dev = link->ioport;
1067 unsigned long flags;
1068
1069 if (!dev)
1070 return;
1071
1072 if (netif_queue_stopped(dev->net))
1073 netif_start_queue(dev->net);
1074
1075 spin_lock_irqsave(&dev->lock, flags);
1076 link->is_suspend = false;
1077 spin_unlock_irqrestore(&dev->lock, flags);
1078}
1079EXPORT_SYMBOL_GPL(gether_resume);
1080
1081/*
1082 * gether_cleanup - remove Ethernet-over-USB device
1083 * Context: may sleep
1084 *
1085 * This is called to free all resources allocated by @gether_setup().
1086 */
1087void gether_cleanup(struct eth_dev *dev)
1088{
1089 if (!dev)
1090 return;
1091
1092 unregister_netdev(dev->net);
1093 flush_work(&dev->work);
1094 free_netdev(dev->net);
1095}
1096EXPORT_SYMBOL_GPL(gether_cleanup);
1097
1098/**
1099 * gether_connect - notify network layer that USB link is active
1100 * @link: the USB link, set up with endpoints, descriptors matching
1101 * current device speed, and any framing wrapper(s) set up.
1102 * Context: irqs blocked
1103 *
1104 * This is called to activate endpoints and let the network layer know
1105 * the connection is active ("carrier detect"). It may cause the I/O
1106 * queues to open and start letting network packets flow, but will in
1107 * any case activate the endpoints so that they respond properly to the
1108 * USB host.
1109 *
1110 * Verify net_device pointer returned using IS_ERR(). If it doesn't
1111 * indicate some error code (negative errno), ep->driver_data values
1112 * have been overwritten.
1113 */
1114struct net_device *gether_connect(struct gether *link)
1115{
1116 struct eth_dev *dev = link->ioport;
1117 int result = 0;
1118
1119 if (!dev)
1120 return ERR_PTR(-EINVAL);
1121
1122 link->in_ep->driver_data = dev;
1123 result = usb_ep_enable(link->in_ep);
1124 if (result != 0) {
1125 DBG(dev, "enable %s --> %d\n",
1126 link->in_ep->name, result);
1127 goto fail0;
1128 }
1129
1130 link->out_ep->driver_data = dev;
1131 result = usb_ep_enable(link->out_ep);
1132 if (result != 0) {
1133 DBG(dev, "enable %s --> %d\n",
1134 link->out_ep->name, result);
1135 goto fail1;
1136 }
1137
1138 if (result == 0)
1139 result = alloc_requests(dev, link, qlen(dev->gadget,
1140 dev->qmult));
1141
1142 if (result == 0) {
1143 dev->zlp = link->is_zlp_ok;
1144 dev->no_skb_reserve = gadget_avoids_skb_reserve(dev->gadget);
1145 DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult));
1146
1147 dev->header_len = link->header_len;
1148 dev->unwrap = link->unwrap;
1149 dev->wrap = link->wrap;
1150
1151 spin_lock(&dev->lock);
1152 dev->port_usb = link;
1153 if (netif_running(dev->net)) {
1154 if (link->open)
1155 link->open(link);
1156 } else {
1157 if (link->close)
1158 link->close(link);
1159 }
1160 spin_unlock(&dev->lock);
1161
1162 netif_carrier_on(dev->net);
1163 if (netif_running(dev->net))
1164 eth_start(dev, GFP_ATOMIC);
1165
1166 netif_device_attach(dev->net);
1167
1168 /* on error, disable any endpoints */
1169 } else {
1170 (void) usb_ep_disable(link->out_ep);
1171fail1:
1172 (void) usb_ep_disable(link->in_ep);
1173 }
1174fail0:
1175 /* caller is responsible for cleanup on error */
1176 if (result < 0)
1177 return ERR_PTR(result);
1178 return dev->net;
1179}
1180EXPORT_SYMBOL_GPL(gether_connect);
1181
1182/**
1183 * gether_disconnect - notify network layer that USB link is inactive
1184 * @link: the USB link, on which gether_connect() was called
1185 * Context: irqs blocked
1186 *
1187 * This is called to deactivate endpoints and let the network layer know
1188 * the connection went inactive ("no carrier").
1189 *
1190 * On return, the state is as if gether_connect() had never been called.
1191 * The endpoints are inactive, and accordingly without active USB I/O.
1192 * Pointers to endpoint descriptors and endpoint private data are nulled.
1193 */
1194void gether_disconnect(struct gether *link)
1195{
1196 struct eth_dev *dev = link->ioport;
1197 struct usb_request *req;
1198
1199 WARN_ON(!dev);
1200 if (!dev)
1201 return;
1202
1203 DBG(dev, "%s\n", __func__);
1204
1205 netif_device_detach(dev->net);
1206 netif_carrier_off(dev->net);
1207
1208 /* disable endpoints, forcing (synchronous) completion
1209 * of all pending i/o. then free the request objects
1210 * and forget about the endpoints.
1211 */
1212 usb_ep_disable(link->in_ep);
1213 spin_lock(&dev->req_lock);
1214 while (!list_empty(&dev->tx_reqs)) {
1215 req = list_first_entry(&dev->tx_reqs, struct usb_request, list);
1216 list_del(&req->list);
1217
1218 spin_unlock(&dev->req_lock);
1219 usb_ep_free_request(link->in_ep, req);
1220 spin_lock(&dev->req_lock);
1221 }
1222 spin_unlock(&dev->req_lock);
1223 link->in_ep->desc = NULL;
1224
1225 usb_ep_disable(link->out_ep);
1226 spin_lock(&dev->req_lock);
1227 while (!list_empty(&dev->rx_reqs)) {
1228 req = list_first_entry(&dev->rx_reqs, struct usb_request, list);
1229 list_del(&req->list);
1230
1231 spin_unlock(&dev->req_lock);
1232 usb_ep_free_request(link->out_ep, req);
1233 spin_lock(&dev->req_lock);
1234 }
1235 spin_unlock(&dev->req_lock);
1236 link->out_ep->desc = NULL;
1237
1238 /* finish forgetting about this USB link episode */
1239 dev->header_len = 0;
1240 dev->unwrap = NULL;
1241 dev->wrap = NULL;
1242
1243 spin_lock(&dev->lock);
1244 dev->port_usb = NULL;
1245 link->is_suspend = false;
1246 spin_unlock(&dev->lock);
1247}
1248EXPORT_SYMBOL_GPL(gether_disconnect);
1249
1250MODULE_LICENSE("GPL");
1251MODULE_AUTHOR("David Brownell");
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
51/* Experiments show that both Linux and Windows hosts allow up to 16k
52 * frame sizes. Set the max size to 15k+52 to prevent allocating 32k
53 * blocks and still have efficient handling. */
54#define GETHER_MAX_ETH_FRAME_LEN 15412
55
56struct eth_dev {
57 /* lock is held while accessing port_usb
58 */
59 spinlock_t lock;
60 struct gether *port_usb;
61
62 struct net_device *net;
63 struct usb_gadget *gadget;
64
65 spinlock_t req_lock; /* guard {rx,tx}_reqs */
66 struct list_head tx_reqs, rx_reqs;
67 atomic_t tx_qlen;
68
69 struct sk_buff_head rx_frames;
70
71 unsigned qmult;
72
73 unsigned header_len;
74 struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
75 int (*unwrap)(struct gether *,
76 struct sk_buff *skb,
77 struct sk_buff_head *list);
78
79 struct work_struct work;
80
81 unsigned long todo;
82#define WORK_RX_MEMORY 0
83
84 bool zlp;
85 u8 host_mac[ETH_ALEN];
86 u8 dev_mac[ETH_ALEN];
87};
88
89/*-------------------------------------------------------------------------*/
90
91#define RX_EXTRA 20 /* bytes guarding against rx overflows */
92
93#define DEFAULT_QLEN 2 /* double buffering by default */
94
95/* for dual-speed hardware, use deeper queues at high/super speed */
96static inline int qlen(struct usb_gadget *gadget, unsigned qmult)
97{
98 if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH ||
99 gadget->speed == USB_SPEED_SUPER))
100 return qmult * DEFAULT_QLEN;
101 else
102 return DEFAULT_QLEN;
103}
104
105/*-------------------------------------------------------------------------*/
106
107/* REVISIT there must be a better way than having two sets
108 * of debug calls ...
109 */
110
111#undef DBG
112#undef VDBG
113#undef ERROR
114#undef INFO
115
116#define xprintk(d, level, fmt, args...) \
117 printk(level "%s: " fmt , (d)->net->name , ## args)
118
119#ifdef DEBUG
120#undef DEBUG
121#define DBG(dev, fmt, args...) \
122 xprintk(dev , KERN_DEBUG , fmt , ## args)
123#else
124#define DBG(dev, fmt, args...) \
125 do { } while (0)
126#endif /* DEBUG */
127
128#ifdef VERBOSE_DEBUG
129#define VDBG DBG
130#else
131#define VDBG(dev, fmt, args...) \
132 do { } while (0)
133#endif /* DEBUG */
134
135#define ERROR(dev, fmt, args...) \
136 xprintk(dev , KERN_ERR , fmt , ## args)
137#define INFO(dev, fmt, args...) \
138 xprintk(dev , KERN_INFO , fmt , ## args)
139
140/*-------------------------------------------------------------------------*/
141
142/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
143
144static int ueth_change_mtu(struct net_device *net, int new_mtu)
145{
146 if (new_mtu <= ETH_HLEN || new_mtu > GETHER_MAX_ETH_FRAME_LEN)
147 return -ERANGE;
148 net->mtu = new_mtu;
149
150 return 0;
151}
152
153static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
154{
155 struct eth_dev *dev = netdev_priv(net);
156
157 strlcpy(p->driver, "g_ether", sizeof(p->driver));
158 strlcpy(p->version, UETH__VERSION, sizeof(p->version));
159 strlcpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version));
160 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info));
161}
162
163/* REVISIT can also support:
164 * - WOL (by tracking suspends and issuing remote wakeup)
165 * - msglevel (implies updated messaging)
166 * - ... probably more ethtool ops
167 */
168
169static const struct ethtool_ops ops = {
170 .get_drvinfo = eth_get_drvinfo,
171 .get_link = ethtool_op_get_link,
172};
173
174static void defer_kevent(struct eth_dev *dev, int flag)
175{
176 if (test_and_set_bit(flag, &dev->todo))
177 return;
178 if (!schedule_work(&dev->work))
179 ERROR(dev, "kevent %d may have been dropped\n", flag);
180 else
181 DBG(dev, "kevent %d scheduled\n", flag);
182}
183
184static void rx_complete(struct usb_ep *ep, struct usb_request *req);
185
186static int
187rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
188{
189 struct sk_buff *skb;
190 int retval = -ENOMEM;
191 size_t size = 0;
192 struct usb_ep *out;
193 unsigned long flags;
194
195 spin_lock_irqsave(&dev->lock, flags);
196 if (dev->port_usb)
197 out = dev->port_usb->out_ep;
198 else
199 out = NULL;
200 spin_unlock_irqrestore(&dev->lock, flags);
201
202 if (!out)
203 return -ENOTCONN;
204
205
206 /* Padding up to RX_EXTRA handles minor disagreements with host.
207 * Normally we use the USB "terminate on short read" convention;
208 * so allow up to (N*maxpacket), since that memory is normally
209 * already allocated. Some hardware doesn't deal well with short
210 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
211 * byte off the end (to force hardware errors on overflow).
212 *
213 * RNDIS uses internal framing, and explicitly allows senders to
214 * pad to end-of-packet. That's potentially nice for speed, but
215 * means receivers can't recover lost synch on their own (because
216 * new packets don't only start after a short RX).
217 */
218 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
219 size += dev->port_usb->header_len;
220 size += out->maxpacket - 1;
221 size -= size % out->maxpacket;
222
223 if (dev->port_usb->is_fixed)
224 size = max_t(size_t, size, dev->port_usb->fixed_out_len);
225
226 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
227 if (skb == NULL) {
228 DBG(dev, "no rx skb\n");
229 goto enomem;
230 }
231
232 /* Some platforms perform better when IP packets are aligned,
233 * but on at least one, checksumming fails otherwise. Note:
234 * RNDIS headers involve variable numbers of LE32 values.
235 */
236 skb_reserve(skb, NET_IP_ALIGN);
237
238 req->buf = skb->data;
239 req->length = size;
240 req->complete = rx_complete;
241 req->context = skb;
242
243 retval = usb_ep_queue(out, req, gfp_flags);
244 if (retval == -ENOMEM)
245enomem:
246 defer_kevent(dev, WORK_RX_MEMORY);
247 if (retval) {
248 DBG(dev, "rx submit --> %d\n", retval);
249 if (skb)
250 dev_kfree_skb_any(skb);
251 spin_lock_irqsave(&dev->req_lock, flags);
252 list_add(&req->list, &dev->rx_reqs);
253 spin_unlock_irqrestore(&dev->req_lock, flags);
254 }
255 return retval;
256}
257
258static void rx_complete(struct usb_ep *ep, struct usb_request *req)
259{
260 struct sk_buff *skb = req->context, *skb2;
261 struct eth_dev *dev = ep->driver_data;
262 int status = req->status;
263
264 switch (status) {
265
266 /* normal completion */
267 case 0:
268 skb_put(skb, req->actual);
269
270 if (dev->unwrap) {
271 unsigned long flags;
272
273 spin_lock_irqsave(&dev->lock, flags);
274 if (dev->port_usb) {
275 status = dev->unwrap(dev->port_usb,
276 skb,
277 &dev->rx_frames);
278 } else {
279 dev_kfree_skb_any(skb);
280 status = -ENOTCONN;
281 }
282 spin_unlock_irqrestore(&dev->lock, flags);
283 } else {
284 skb_queue_tail(&dev->rx_frames, skb);
285 }
286 skb = NULL;
287
288 skb2 = skb_dequeue(&dev->rx_frames);
289 while (skb2) {
290 if (status < 0
291 || ETH_HLEN > skb2->len
292 || skb2->len > GETHER_MAX_ETH_FRAME_LEN) {
293 dev->net->stats.rx_errors++;
294 dev->net->stats.rx_length_errors++;
295 DBG(dev, "rx length %d\n", skb2->len);
296 dev_kfree_skb_any(skb2);
297 goto next_frame;
298 }
299 skb2->protocol = eth_type_trans(skb2, dev->net);
300 dev->net->stats.rx_packets++;
301 dev->net->stats.rx_bytes += skb2->len;
302
303 /* no buffer copies needed, unless hardware can't
304 * use skb buffers.
305 */
306 status = netif_rx(skb2);
307next_frame:
308 skb2 = skb_dequeue(&dev->rx_frames);
309 }
310 break;
311
312 /* software-driven interface shutdown */
313 case -ECONNRESET: /* unlink */
314 case -ESHUTDOWN: /* disconnect etc */
315 VDBG(dev, "rx shutdown, code %d\n", status);
316 goto quiesce;
317
318 /* for hardware automagic (such as pxa) */
319 case -ECONNABORTED: /* endpoint reset */
320 DBG(dev, "rx %s reset\n", ep->name);
321 defer_kevent(dev, WORK_RX_MEMORY);
322quiesce:
323 dev_kfree_skb_any(skb);
324 goto clean;
325
326 /* data overrun */
327 case -EOVERFLOW:
328 dev->net->stats.rx_over_errors++;
329 /* FALLTHROUGH */
330
331 default:
332 dev->net->stats.rx_errors++;
333 DBG(dev, "rx status %d\n", status);
334 break;
335 }
336
337 if (skb)
338 dev_kfree_skb_any(skb);
339 if (!netif_running(dev->net)) {
340clean:
341 spin_lock(&dev->req_lock);
342 list_add(&req->list, &dev->rx_reqs);
343 spin_unlock(&dev->req_lock);
344 req = NULL;
345 }
346 if (req)
347 rx_submit(dev, req, GFP_ATOMIC);
348}
349
350static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
351{
352 unsigned i;
353 struct usb_request *req;
354
355 if (!n)
356 return -ENOMEM;
357
358 /* queue/recycle up to N requests */
359 i = n;
360 list_for_each_entry(req, list, list) {
361 if (i-- == 0)
362 goto extra;
363 }
364 while (i--) {
365 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
366 if (!req)
367 return list_empty(list) ? -ENOMEM : 0;
368 list_add(&req->list, list);
369 }
370 return 0;
371
372extra:
373 /* free extras */
374 for (;;) {
375 struct list_head *next;
376
377 next = req->list.next;
378 list_del(&req->list);
379 usb_ep_free_request(ep, req);
380
381 if (next == list)
382 break;
383
384 req = container_of(next, struct usb_request, list);
385 }
386 return 0;
387}
388
389static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
390{
391 int status;
392
393 spin_lock(&dev->req_lock);
394 status = prealloc(&dev->tx_reqs, link->in_ep, n);
395 if (status < 0)
396 goto fail;
397 status = prealloc(&dev->rx_reqs, link->out_ep, n);
398 if (status < 0)
399 goto fail;
400 goto done;
401fail:
402 DBG(dev, "can't alloc requests\n");
403done:
404 spin_unlock(&dev->req_lock);
405 return status;
406}
407
408static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
409{
410 struct usb_request *req;
411 unsigned long flags;
412
413 /* fill unused rxq slots with some skb */
414 spin_lock_irqsave(&dev->req_lock, flags);
415 while (!list_empty(&dev->rx_reqs)) {
416 req = container_of(dev->rx_reqs.next,
417 struct usb_request, list);
418 list_del_init(&req->list);
419 spin_unlock_irqrestore(&dev->req_lock, flags);
420
421 if (rx_submit(dev, req, gfp_flags) < 0) {
422 defer_kevent(dev, WORK_RX_MEMORY);
423 return;
424 }
425
426 spin_lock_irqsave(&dev->req_lock, flags);
427 }
428 spin_unlock_irqrestore(&dev->req_lock, flags);
429}
430
431static void eth_work(struct work_struct *work)
432{
433 struct eth_dev *dev = container_of(work, struct eth_dev, work);
434
435 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
436 if (netif_running(dev->net))
437 rx_fill(dev, GFP_KERNEL);
438 }
439
440 if (dev->todo)
441 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
442}
443
444static void tx_complete(struct usb_ep *ep, struct usb_request *req)
445{
446 struct sk_buff *skb = req->context;
447 struct eth_dev *dev = ep->driver_data;
448
449 switch (req->status) {
450 default:
451 dev->net->stats.tx_errors++;
452 VDBG(dev, "tx err %d\n", req->status);
453 /* FALLTHROUGH */
454 case -ECONNRESET: /* unlink */
455 case -ESHUTDOWN: /* disconnect etc */
456 break;
457 case 0:
458 dev->net->stats.tx_bytes += skb->len;
459 }
460 dev->net->stats.tx_packets++;
461
462 spin_lock(&dev->req_lock);
463 list_add(&req->list, &dev->tx_reqs);
464 spin_unlock(&dev->req_lock);
465 dev_kfree_skb_any(skb);
466
467 atomic_dec(&dev->tx_qlen);
468 if (netif_carrier_ok(dev->net))
469 netif_wake_queue(dev->net);
470}
471
472static inline int is_promisc(u16 cdc_filter)
473{
474 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
475}
476
477static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
478 struct net_device *net)
479{
480 struct eth_dev *dev = netdev_priv(net);
481 int length = 0;
482 int retval;
483 struct usb_request *req = NULL;
484 unsigned long flags;
485 struct usb_ep *in;
486 u16 cdc_filter;
487
488 spin_lock_irqsave(&dev->lock, flags);
489 if (dev->port_usb) {
490 in = dev->port_usb->in_ep;
491 cdc_filter = dev->port_usb->cdc_filter;
492 } else {
493 in = NULL;
494 cdc_filter = 0;
495 }
496 spin_unlock_irqrestore(&dev->lock, flags);
497
498 if (skb && !in) {
499 dev_kfree_skb_any(skb);
500 return NETDEV_TX_OK;
501 }
502
503 /* apply outgoing CDC or RNDIS filters */
504 if (skb && !is_promisc(cdc_filter)) {
505 u8 *dest = skb->data;
506
507 if (is_multicast_ether_addr(dest)) {
508 u16 type;
509
510 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
511 * SET_ETHERNET_MULTICAST_FILTERS requests
512 */
513 if (is_broadcast_ether_addr(dest))
514 type = USB_CDC_PACKET_TYPE_BROADCAST;
515 else
516 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
517 if (!(cdc_filter & type)) {
518 dev_kfree_skb_any(skb);
519 return NETDEV_TX_OK;
520 }
521 }
522 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
523 }
524
525 spin_lock_irqsave(&dev->req_lock, flags);
526 /*
527 * this freelist can be empty if an interrupt triggered disconnect()
528 * and reconfigured the gadget (shutting down this queue) after the
529 * network stack decided to xmit but before we got the spinlock.
530 */
531 if (list_empty(&dev->tx_reqs)) {
532 spin_unlock_irqrestore(&dev->req_lock, flags);
533 return NETDEV_TX_BUSY;
534 }
535
536 req = container_of(dev->tx_reqs.next, struct usb_request, list);
537 list_del(&req->list);
538
539 /* temporarily stop TX queue when the freelist empties */
540 if (list_empty(&dev->tx_reqs))
541 netif_stop_queue(net);
542 spin_unlock_irqrestore(&dev->req_lock, flags);
543
544 /* no buffer copies needed, unless the network stack did it
545 * or the hardware can't use skb buffers.
546 * or there's not enough space for extra headers we need
547 */
548 if (dev->wrap) {
549 unsigned long flags;
550
551 spin_lock_irqsave(&dev->lock, flags);
552 if (dev->port_usb)
553 skb = dev->wrap(dev->port_usb, skb);
554 spin_unlock_irqrestore(&dev->lock, flags);
555 if (!skb) {
556 /* Multi frame CDC protocols may store the frame for
557 * later which is not a dropped frame.
558 */
559 if (dev->port_usb->supports_multi_frame)
560 goto multiframe;
561 goto drop;
562 }
563 }
564
565 length = skb->len;
566 req->buf = skb->data;
567 req->context = skb;
568 req->complete = tx_complete;
569
570 /* NCM requires no zlp if transfer is dwNtbInMaxSize */
571 if (dev->port_usb->is_fixed &&
572 length == dev->port_usb->fixed_in_len &&
573 (length % in->maxpacket) == 0)
574 req->zero = 0;
575 else
576 req->zero = 1;
577
578 /* use zlp framing on tx for strict CDC-Ether conformance,
579 * though any robust network rx path ignores extra padding.
580 * and some hardware doesn't like to write zlps.
581 */
582 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)
583 length++;
584
585 req->length = length;
586
587 /* throttle high/super speed IRQ rate back slightly */
588 if (gadget_is_dualspeed(dev->gadget))
589 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH ||
590 dev->gadget->speed == USB_SPEED_SUPER)
591 ? ((atomic_read(&dev->tx_qlen) % dev->qmult) != 0)
592 : 0;
593
594 retval = usb_ep_queue(in, req, GFP_ATOMIC);
595 switch (retval) {
596 default:
597 DBG(dev, "tx queue err %d\n", retval);
598 break;
599 case 0:
600 net->trans_start = jiffies;
601 atomic_inc(&dev->tx_qlen);
602 }
603
604 if (retval) {
605 dev_kfree_skb_any(skb);
606drop:
607 dev->net->stats.tx_dropped++;
608multiframe:
609 spin_lock_irqsave(&dev->req_lock, flags);
610 if (list_empty(&dev->tx_reqs))
611 netif_start_queue(net);
612 list_add(&req->list, &dev->tx_reqs);
613 spin_unlock_irqrestore(&dev->req_lock, flags);
614 }
615 return NETDEV_TX_OK;
616}
617
618/*-------------------------------------------------------------------------*/
619
620static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
621{
622 DBG(dev, "%s\n", __func__);
623
624 /* fill the rx queue */
625 rx_fill(dev, gfp_flags);
626
627 /* and open the tx floodgates */
628 atomic_set(&dev->tx_qlen, 0);
629 netif_wake_queue(dev->net);
630}
631
632static int eth_open(struct net_device *net)
633{
634 struct eth_dev *dev = netdev_priv(net);
635 struct gether *link;
636
637 DBG(dev, "%s\n", __func__);
638 if (netif_carrier_ok(dev->net))
639 eth_start(dev, GFP_KERNEL);
640
641 spin_lock_irq(&dev->lock);
642 link = dev->port_usb;
643 if (link && link->open)
644 link->open(link);
645 spin_unlock_irq(&dev->lock);
646
647 return 0;
648}
649
650static int eth_stop(struct net_device *net)
651{
652 struct eth_dev *dev = netdev_priv(net);
653 unsigned long flags;
654
655 VDBG(dev, "%s\n", __func__);
656 netif_stop_queue(net);
657
658 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
659 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
660 dev->net->stats.rx_errors, dev->net->stats.tx_errors
661 );
662
663 /* ensure there are no more active requests */
664 spin_lock_irqsave(&dev->lock, flags);
665 if (dev->port_usb) {
666 struct gether *link = dev->port_usb;
667 const struct usb_endpoint_descriptor *in;
668 const struct usb_endpoint_descriptor *out;
669
670 if (link->close)
671 link->close(link);
672
673 /* NOTE: we have no abort-queue primitive we could use
674 * to cancel all pending I/O. Instead, we disable then
675 * reenable the endpoints ... this idiom may leave toggle
676 * wrong, but that's a self-correcting error.
677 *
678 * REVISIT: we *COULD* just let the transfers complete at
679 * their own pace; the network stack can handle old packets.
680 * For the moment we leave this here, since it works.
681 */
682 in = link->in_ep->desc;
683 out = link->out_ep->desc;
684 usb_ep_disable(link->in_ep);
685 usb_ep_disable(link->out_ep);
686 if (netif_carrier_ok(net)) {
687 DBG(dev, "host still using in/out endpoints\n");
688 link->in_ep->desc = in;
689 link->out_ep->desc = out;
690 usb_ep_enable(link->in_ep);
691 usb_ep_enable(link->out_ep);
692 }
693 }
694 spin_unlock_irqrestore(&dev->lock, flags);
695
696 return 0;
697}
698
699/*-------------------------------------------------------------------------*/
700
701static int get_ether_addr(const char *str, u8 *dev_addr)
702{
703 if (str) {
704 unsigned i;
705
706 for (i = 0; i < 6; i++) {
707 unsigned char num;
708
709 if ((*str == '.') || (*str == ':'))
710 str++;
711 num = hex_to_bin(*str++) << 4;
712 num |= hex_to_bin(*str++);
713 dev_addr [i] = num;
714 }
715 if (is_valid_ether_addr(dev_addr))
716 return 0;
717 }
718 eth_random_addr(dev_addr);
719 return 1;
720}
721
722static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len)
723{
724 if (len < 18)
725 return -EINVAL;
726
727 snprintf(str, len, "%pM", dev_addr);
728 return 18;
729}
730
731static const struct net_device_ops eth_netdev_ops = {
732 .ndo_open = eth_open,
733 .ndo_stop = eth_stop,
734 .ndo_start_xmit = eth_start_xmit,
735 .ndo_change_mtu = ueth_change_mtu,
736 .ndo_set_mac_address = eth_mac_addr,
737 .ndo_validate_addr = eth_validate_addr,
738};
739
740static struct device_type gadget_type = {
741 .name = "gadget",
742};
743
744/**
745 * gether_setup_name - initialize one ethernet-over-usb link
746 * @g: gadget to associated with these links
747 * @ethaddr: NULL, or a buffer in which the ethernet address of the
748 * host side of the link is recorded
749 * @netname: name for network device (for example, "usb")
750 * Context: may sleep
751 *
752 * This sets up the single network link that may be exported by a
753 * gadget driver using this framework. The link layer addresses are
754 * set up using module parameters.
755 *
756 * Returns an eth_dev pointer on success, or an ERR_PTR on failure.
757 */
758struct eth_dev *gether_setup_name(struct usb_gadget *g,
759 const char *dev_addr, const char *host_addr,
760 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname)
761{
762 struct eth_dev *dev;
763 struct net_device *net;
764 int status;
765
766 net = alloc_etherdev(sizeof *dev);
767 if (!net)
768 return ERR_PTR(-ENOMEM);
769
770 dev = netdev_priv(net);
771 spin_lock_init(&dev->lock);
772 spin_lock_init(&dev->req_lock);
773 INIT_WORK(&dev->work, eth_work);
774 INIT_LIST_HEAD(&dev->tx_reqs);
775 INIT_LIST_HEAD(&dev->rx_reqs);
776
777 skb_queue_head_init(&dev->rx_frames);
778
779 /* network device setup */
780 dev->net = net;
781 dev->qmult = qmult;
782 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
783
784 if (get_ether_addr(dev_addr, net->dev_addr))
785 dev_warn(&g->dev,
786 "using random %s ethernet address\n", "self");
787 if (get_ether_addr(host_addr, dev->host_mac))
788 dev_warn(&g->dev,
789 "using random %s ethernet address\n", "host");
790
791 if (ethaddr)
792 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
793
794 net->netdev_ops = ð_netdev_ops;
795
796 net->ethtool_ops = &ops;
797
798 dev->gadget = g;
799 SET_NETDEV_DEV(net, &g->dev);
800 SET_NETDEV_DEVTYPE(net, &gadget_type);
801
802 status = register_netdev(net);
803 if (status < 0) {
804 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
805 free_netdev(net);
806 dev = ERR_PTR(status);
807 } else {
808 INFO(dev, "MAC %pM\n", net->dev_addr);
809 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
810
811 /*
812 * two kinds of host-initiated state changes:
813 * - iff DATA transfer is active, carrier is "on"
814 * - tx queueing enabled if open *and* carrier is "on"
815 */
816 netif_carrier_off(net);
817 }
818
819 return dev;
820}
821EXPORT_SYMBOL_GPL(gether_setup_name);
822
823struct net_device *gether_setup_name_default(const char *netname)
824{
825 struct net_device *net;
826 struct eth_dev *dev;
827
828 net = alloc_etherdev(sizeof(*dev));
829 if (!net)
830 return ERR_PTR(-ENOMEM);
831
832 dev = netdev_priv(net);
833 spin_lock_init(&dev->lock);
834 spin_lock_init(&dev->req_lock);
835 INIT_WORK(&dev->work, eth_work);
836 INIT_LIST_HEAD(&dev->tx_reqs);
837 INIT_LIST_HEAD(&dev->rx_reqs);
838
839 skb_queue_head_init(&dev->rx_frames);
840
841 /* network device setup */
842 dev->net = net;
843 dev->qmult = QMULT_DEFAULT;
844 snprintf(net->name, sizeof(net->name), "%s%%d", netname);
845
846 eth_random_addr(dev->dev_mac);
847 pr_warn("using random %s ethernet address\n", "self");
848 eth_random_addr(dev->host_mac);
849 pr_warn("using random %s ethernet address\n", "host");
850
851 net->netdev_ops = ð_netdev_ops;
852
853 net->ethtool_ops = &ops;
854 SET_NETDEV_DEVTYPE(net, &gadget_type);
855
856 return net;
857}
858EXPORT_SYMBOL_GPL(gether_setup_name_default);
859
860int gether_register_netdev(struct net_device *net)
861{
862 struct eth_dev *dev;
863 struct usb_gadget *g;
864 struct sockaddr sa;
865 int status;
866
867 if (!net->dev.parent)
868 return -EINVAL;
869 dev = netdev_priv(net);
870 g = dev->gadget;
871 status = register_netdev(net);
872 if (status < 0) {
873 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
874 return status;
875 } else {
876 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
877
878 /* two kinds of host-initiated state changes:
879 * - iff DATA transfer is active, carrier is "on"
880 * - tx queueing enabled if open *and* carrier is "on"
881 */
882 netif_carrier_off(net);
883 }
884 sa.sa_family = net->type;
885 memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN);
886 rtnl_lock();
887 status = dev_set_mac_address(net, &sa);
888 rtnl_unlock();
889 if (status)
890 pr_warn("cannot set self ethernet address: %d\n", status);
891 else
892 INFO(dev, "MAC %pM\n", dev->dev_mac);
893
894 return status;
895}
896EXPORT_SYMBOL_GPL(gether_register_netdev);
897
898void gether_set_gadget(struct net_device *net, struct usb_gadget *g)
899{
900 struct eth_dev *dev;
901
902 dev = netdev_priv(net);
903 dev->gadget = g;
904 SET_NETDEV_DEV(net, &g->dev);
905}
906EXPORT_SYMBOL_GPL(gether_set_gadget);
907
908int gether_set_dev_addr(struct net_device *net, const char *dev_addr)
909{
910 struct eth_dev *dev;
911 u8 new_addr[ETH_ALEN];
912
913 dev = netdev_priv(net);
914 if (get_ether_addr(dev_addr, new_addr))
915 return -EINVAL;
916 memcpy(dev->dev_mac, new_addr, ETH_ALEN);
917 return 0;
918}
919EXPORT_SYMBOL_GPL(gether_set_dev_addr);
920
921int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len)
922{
923 struct eth_dev *dev;
924
925 dev = netdev_priv(net);
926 return get_ether_addr_str(dev->dev_mac, dev_addr, len);
927}
928EXPORT_SYMBOL_GPL(gether_get_dev_addr);
929
930int gether_set_host_addr(struct net_device *net, const char *host_addr)
931{
932 struct eth_dev *dev;
933 u8 new_addr[ETH_ALEN];
934
935 dev = netdev_priv(net);
936 if (get_ether_addr(host_addr, new_addr))
937 return -EINVAL;
938 memcpy(dev->host_mac, new_addr, ETH_ALEN);
939 return 0;
940}
941EXPORT_SYMBOL_GPL(gether_set_host_addr);
942
943int gether_get_host_addr(struct net_device *net, char *host_addr, int len)
944{
945 struct eth_dev *dev;
946
947 dev = netdev_priv(net);
948 return get_ether_addr_str(dev->host_mac, host_addr, len);
949}
950EXPORT_SYMBOL_GPL(gether_get_host_addr);
951
952int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len)
953{
954 struct eth_dev *dev;
955
956 if (len < 13)
957 return -EINVAL;
958
959 dev = netdev_priv(net);
960 snprintf(host_addr, len, "%pm", dev->host_mac);
961
962 return strlen(host_addr);
963}
964EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc);
965
966void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN])
967{
968 struct eth_dev *dev;
969
970 dev = netdev_priv(net);
971 memcpy(host_mac, dev->host_mac, ETH_ALEN);
972}
973EXPORT_SYMBOL_GPL(gether_get_host_addr_u8);
974
975void gether_set_qmult(struct net_device *net, unsigned qmult)
976{
977 struct eth_dev *dev;
978
979 dev = netdev_priv(net);
980 dev->qmult = qmult;
981}
982EXPORT_SYMBOL_GPL(gether_set_qmult);
983
984unsigned gether_get_qmult(struct net_device *net)
985{
986 struct eth_dev *dev;
987
988 dev = netdev_priv(net);
989 return dev->qmult;
990}
991EXPORT_SYMBOL_GPL(gether_get_qmult);
992
993int gether_get_ifname(struct net_device *net, char *name, int len)
994{
995 rtnl_lock();
996 strlcpy(name, netdev_name(net), len);
997 rtnl_unlock();
998 return strlen(name);
999}
1000EXPORT_SYMBOL_GPL(gether_get_ifname);
1001
1002/**
1003 * gether_cleanup - remove Ethernet-over-USB device
1004 * Context: may sleep
1005 *
1006 * This is called to free all resources allocated by @gether_setup().
1007 */
1008void gether_cleanup(struct eth_dev *dev)
1009{
1010 if (!dev)
1011 return;
1012
1013 unregister_netdev(dev->net);
1014 flush_work(&dev->work);
1015 free_netdev(dev->net);
1016}
1017EXPORT_SYMBOL_GPL(gether_cleanup);
1018
1019/**
1020 * gether_connect - notify network layer that USB link is active
1021 * @link: the USB link, set up with endpoints, descriptors matching
1022 * current device speed, and any framing wrapper(s) set up.
1023 * Context: irqs blocked
1024 *
1025 * This is called to activate endpoints and let the network layer know
1026 * the connection is active ("carrier detect"). It may cause the I/O
1027 * queues to open and start letting network packets flow, but will in
1028 * any case activate the endpoints so that they respond properly to the
1029 * USB host.
1030 *
1031 * Verify net_device pointer returned using IS_ERR(). If it doesn't
1032 * indicate some error code (negative errno), ep->driver_data values
1033 * have been overwritten.
1034 */
1035struct net_device *gether_connect(struct gether *link)
1036{
1037 struct eth_dev *dev = link->ioport;
1038 int result = 0;
1039
1040 if (!dev)
1041 return ERR_PTR(-EINVAL);
1042
1043 link->in_ep->driver_data = dev;
1044 result = usb_ep_enable(link->in_ep);
1045 if (result != 0) {
1046 DBG(dev, "enable %s --> %d\n",
1047 link->in_ep->name, result);
1048 goto fail0;
1049 }
1050
1051 link->out_ep->driver_data = dev;
1052 result = usb_ep_enable(link->out_ep);
1053 if (result != 0) {
1054 DBG(dev, "enable %s --> %d\n",
1055 link->out_ep->name, result);
1056 goto fail1;
1057 }
1058
1059 if (result == 0)
1060 result = alloc_requests(dev, link, qlen(dev->gadget,
1061 dev->qmult));
1062
1063 if (result == 0) {
1064 dev->zlp = link->is_zlp_ok;
1065 DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult));
1066
1067 dev->header_len = link->header_len;
1068 dev->unwrap = link->unwrap;
1069 dev->wrap = link->wrap;
1070
1071 spin_lock(&dev->lock);
1072 dev->port_usb = link;
1073 if (netif_running(dev->net)) {
1074 if (link->open)
1075 link->open(link);
1076 } else {
1077 if (link->close)
1078 link->close(link);
1079 }
1080 spin_unlock(&dev->lock);
1081
1082 netif_carrier_on(dev->net);
1083 if (netif_running(dev->net))
1084 eth_start(dev, GFP_ATOMIC);
1085
1086 /* on error, disable any endpoints */
1087 } else {
1088 (void) usb_ep_disable(link->out_ep);
1089fail1:
1090 (void) usb_ep_disable(link->in_ep);
1091 }
1092fail0:
1093 /* caller is responsible for cleanup on error */
1094 if (result < 0)
1095 return ERR_PTR(result);
1096 return dev->net;
1097}
1098EXPORT_SYMBOL_GPL(gether_connect);
1099
1100/**
1101 * gether_disconnect - notify network layer that USB link is inactive
1102 * @link: the USB link, on which gether_connect() was called
1103 * Context: irqs blocked
1104 *
1105 * This is called to deactivate endpoints and let the network layer know
1106 * the connection went inactive ("no carrier").
1107 *
1108 * On return, the state is as if gether_connect() had never been called.
1109 * The endpoints are inactive, and accordingly without active USB I/O.
1110 * Pointers to endpoint descriptors and endpoint private data are nulled.
1111 */
1112void gether_disconnect(struct gether *link)
1113{
1114 struct eth_dev *dev = link->ioport;
1115 struct usb_request *req;
1116
1117 WARN_ON(!dev);
1118 if (!dev)
1119 return;
1120
1121 DBG(dev, "%s\n", __func__);
1122
1123 netif_stop_queue(dev->net);
1124 netif_carrier_off(dev->net);
1125
1126 /* disable endpoints, forcing (synchronous) completion
1127 * of all pending i/o. then free the request objects
1128 * and forget about the endpoints.
1129 */
1130 usb_ep_disable(link->in_ep);
1131 spin_lock(&dev->req_lock);
1132 while (!list_empty(&dev->tx_reqs)) {
1133 req = container_of(dev->tx_reqs.next,
1134 struct usb_request, list);
1135 list_del(&req->list);
1136
1137 spin_unlock(&dev->req_lock);
1138 usb_ep_free_request(link->in_ep, req);
1139 spin_lock(&dev->req_lock);
1140 }
1141 spin_unlock(&dev->req_lock);
1142 link->in_ep->desc = NULL;
1143
1144 usb_ep_disable(link->out_ep);
1145 spin_lock(&dev->req_lock);
1146 while (!list_empty(&dev->rx_reqs)) {
1147 req = container_of(dev->rx_reqs.next,
1148 struct usb_request, list);
1149 list_del(&req->list);
1150
1151 spin_unlock(&dev->req_lock);
1152 usb_ep_free_request(link->out_ep, req);
1153 spin_lock(&dev->req_lock);
1154 }
1155 spin_unlock(&dev->req_lock);
1156 link->out_ep->desc = NULL;
1157
1158 /* finish forgetting about this USB link episode */
1159 dev->header_len = 0;
1160 dev->unwrap = NULL;
1161 dev->wrap = NULL;
1162
1163 spin_lock(&dev->lock);
1164 dev->port_usb = NULL;
1165 spin_unlock(&dev->lock);
1166}
1167EXPORT_SYMBOL_GPL(gether_disconnect);
1168
1169MODULE_LICENSE("GPL");
1170MODULE_AUTHOR("David Brownell");