blob: c665219539170988c1083d6b379dec303b68fb08 [file] [log] [blame]
David Brownell2b3d9422008-06-19 18:19:28 -07001/*
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 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23/* #define VERBOSE_DEBUG */
24
25#include <linux/kernel.h>
26#include <linux/utsname.h>
27#include <linux/device.h>
28#include <linux/ctype.h>
29#include <linux/etherdevice.h>
30#include <linux/ethtool.h>
31
32#include "u_ether.h"
33
34
35/*
36 * This component encapsulates the Ethernet link glue needed to provide
37 * one (!) network link through the USB gadget stack, normally "usb0".
38 *
39 * The control and data models are handled by the function driver which
40 * connects to this code; such as CDC Ethernet, "CDC Subset", or RNDIS.
41 * That includes all descriptor and endpoint management.
42 *
43 * Link level addressing is handled by this component using module
44 * parameters; if no such parameters are provided, random link level
45 * addresses are used. Each end of the link uses one address. The
46 * host end address is exported in various ways, and is often recorded
47 * in configuration databases.
48 *
49 * The driver which assembles each configuration using such a link is
50 * responsible for ensuring that each configuration includes at most one
51 * instance of is network link. (The network layer provides ways for
52 * this single "physical" link to be used by multiple virtual links.)
53 */
54
David Brownell8a1ce2c2008-08-18 17:43:56 -070055#define UETH__VERSION "29-May-2008"
David Brownell2b3d9422008-06-19 18:19:28 -070056
57struct eth_dev {
58 /* lock is held while accessing port_usb
59 * or updating its backlink port_usb->ioport
60 */
61 spinlock_t lock;
62 struct gether *port_usb;
63
64 struct net_device *net;
65 struct usb_gadget *gadget;
66
67 spinlock_t req_lock; /* guard {rx,tx}_reqs */
68 struct list_head tx_reqs, rx_reqs;
69 atomic_t tx_qlen;
70
71 unsigned header_len;
72 struct sk_buff *(*wrap)(struct sk_buff *skb);
73 int (*unwrap)(struct sk_buff *skb);
74
75 struct work_struct work;
76
77 unsigned long todo;
78#define WORK_RX_MEMORY 0
79
80 bool zlp;
81 u8 host_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
91#ifdef CONFIG_USB_GADGET_DUALSPEED
92
93static unsigned qmult = 5;
94module_param(qmult, uint, S_IRUGO|S_IWUSR);
95MODULE_PARM_DESC(qmult, "queue length multiplier at high speed");
96
97#else /* full speed (low speed doesn't do bulk) */
98#define qmult 1
99#endif
100
101/* for dual-speed hardware, use deeper queues at highspeed */
102static inline int qlen(struct usb_gadget *gadget)
103{
104 if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH)
105 return qmult * DEFAULT_QLEN;
106 else
107 return DEFAULT_QLEN;
108}
109
110/*-------------------------------------------------------------------------*/
111
112/* REVISIT there must be a better way than having two sets
113 * of debug calls ...
114 */
115
116#undef DBG
117#undef VDBG
118#undef ERROR
David Brownell2b3d9422008-06-19 18:19:28 -0700119#undef INFO
120
121#define xprintk(d, level, fmt, args...) \
122 printk(level "%s: " fmt , (d)->net->name , ## args)
123
124#ifdef DEBUG
125#undef DEBUG
126#define DBG(dev, fmt, args...) \
127 xprintk(dev , KERN_DEBUG , fmt , ## args)
128#else
129#define DBG(dev, fmt, args...) \
130 do { } while (0)
131#endif /* DEBUG */
132
133#ifdef VERBOSE_DEBUG
134#define VDBG DBG
135#else
136#define VDBG(dev, fmt, args...) \
137 do { } while (0)
138#endif /* DEBUG */
139
140#define ERROR(dev, fmt, args...) \
141 xprintk(dev , KERN_ERR , fmt , ## args)
David Brownell2b3d9422008-06-19 18:19:28 -0700142#define INFO(dev, fmt, args...) \
143 xprintk(dev , KERN_INFO , fmt , ## args)
144
145/*-------------------------------------------------------------------------*/
146
147/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
148
Stephen Hemmingerccad6372008-11-19 22:42:31 -0800149static int ueth_change_mtu(struct net_device *net, int new_mtu)
David Brownell2b3d9422008-06-19 18:19:28 -0700150{
151 struct eth_dev *dev = netdev_priv(net);
152 unsigned long flags;
153 int status = 0;
154
155 /* don't change MTU on "live" link (peer won't know) */
156 spin_lock_irqsave(&dev->lock, flags);
157 if (dev->port_usb)
158 status = -EBUSY;
159 else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
160 status = -ERANGE;
161 else
162 net->mtu = new_mtu;
163 spin_unlock_irqrestore(&dev->lock, flags);
164
165 return status;
166}
167
168static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
169{
170 struct eth_dev *dev = netdev_priv(net);
171
172 strlcpy(p->driver, "g_ether", sizeof p->driver);
David Brownell8a1ce2c2008-08-18 17:43:56 -0700173 strlcpy(p->version, UETH__VERSION, sizeof p->version);
David Brownell2b3d9422008-06-19 18:19:28 -0700174 strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
175 strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
176}
177
David Brownell2b3d9422008-06-19 18:19:28 -0700178/* REVISIT can also support:
179 * - WOL (by tracking suspends and issuing remote wakeup)
180 * - msglevel (implies updated messaging)
181 * - ... probably more ethtool ops
182 */
183
Stephen Hemminger0fc0b732009-09-02 01:03:33 -0700184static const struct ethtool_ops ops = {
David Brownell2b3d9422008-06-19 18:19:28 -0700185 .get_drvinfo = eth_get_drvinfo,
Jonathan McDowell237e75b2009-03-26 00:45:27 -0700186 .get_link = ethtool_op_get_link,
David Brownell2b3d9422008-06-19 18:19:28 -0700187};
188
189static void defer_kevent(struct eth_dev *dev, int flag)
190{
191 if (test_and_set_bit(flag, &dev->todo))
192 return;
193 if (!schedule_work(&dev->work))
194 ERROR(dev, "kevent %d may have been dropped\n", flag);
195 else
196 DBG(dev, "kevent %d scheduled\n", flag);
197}
198
199static void rx_complete(struct usb_ep *ep, struct usb_request *req);
200
201static int
202rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
203{
204 struct sk_buff *skb;
205 int retval = -ENOMEM;
206 size_t size = 0;
207 struct usb_ep *out;
208 unsigned long flags;
209
210 spin_lock_irqsave(&dev->lock, flags);
211 if (dev->port_usb)
212 out = dev->port_usb->out_ep;
213 else
214 out = NULL;
215 spin_unlock_irqrestore(&dev->lock, flags);
216
217 if (!out)
218 return -ENOTCONN;
219
220
221 /* Padding up to RX_EXTRA handles minor disagreements with host.
222 * Normally we use the USB "terminate on short read" convention;
223 * so allow up to (N*maxpacket), since that memory is normally
224 * already allocated. Some hardware doesn't deal well with short
225 * reads (e.g. DMA must be N*maxpacket), so for now don't trim a
226 * byte off the end (to force hardware errors on overflow).
227 *
228 * RNDIS uses internal framing, and explicitly allows senders to
229 * pad to end-of-packet. That's potentially nice for speed, but
230 * means receivers can't recover lost synch on their own (because
231 * new packets don't only start after a short RX).
232 */
233 size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
234 size += dev->port_usb->header_len;
235 size += out->maxpacket - 1;
236 size -= size % out->maxpacket;
237
238 skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
239 if (skb == NULL) {
240 DBG(dev, "no rx skb\n");
241 goto enomem;
242 }
243
244 /* Some platforms perform better when IP packets are aligned,
245 * but on at least one, checksumming fails otherwise. Note:
246 * RNDIS headers involve variable numbers of LE32 values.
247 */
248 skb_reserve(skb, NET_IP_ALIGN);
249
250 req->buf = skb->data;
251 req->length = size;
252 req->complete = rx_complete;
253 req->context = skb;
254
255 retval = usb_ep_queue(out, req, gfp_flags);
256 if (retval == -ENOMEM)
257enomem:
258 defer_kevent(dev, WORK_RX_MEMORY);
259 if (retval) {
260 DBG(dev, "rx submit --> %d\n", retval);
261 if (skb)
262 dev_kfree_skb_any(skb);
263 spin_lock_irqsave(&dev->req_lock, flags);
264 list_add(&req->list, &dev->rx_reqs);
265 spin_unlock_irqrestore(&dev->req_lock, flags);
266 }
267 return retval;
268}
269
270static void rx_complete(struct usb_ep *ep, struct usb_request *req)
271{
272 struct sk_buff *skb = req->context;
273 struct eth_dev *dev = ep->driver_data;
274 int status = req->status;
275
276 switch (status) {
277
278 /* normal completion */
279 case 0:
280 skb_put(skb, req->actual);
281 if (dev->unwrap)
282 status = dev->unwrap(skb);
283 if (status < 0
284 || ETH_HLEN > skb->len
285 || skb->len > ETH_FRAME_LEN) {
286 dev->net->stats.rx_errors++;
287 dev->net->stats.rx_length_errors++;
288 DBG(dev, "rx length %d\n", skb->len);
289 break;
290 }
291
292 skb->protocol = eth_type_trans(skb, dev->net);
293 dev->net->stats.rx_packets++;
294 dev->net->stats.rx_bytes += skb->len;
295
296 /* no buffer copies needed, unless hardware can't
297 * use skb buffers.
298 */
299 status = netif_rx(skb);
300 skb = NULL;
301 break;
302
303 /* software-driven interface shutdown */
304 case -ECONNRESET: /* unlink */
305 case -ESHUTDOWN: /* disconnect etc */
306 VDBG(dev, "rx shutdown, code %d\n", status);
307 goto quiesce;
308
309 /* for hardware automagic (such as pxa) */
310 case -ECONNABORTED: /* endpoint reset */
311 DBG(dev, "rx %s reset\n", ep->name);
312 defer_kevent(dev, WORK_RX_MEMORY);
313quiesce:
314 dev_kfree_skb_any(skb);
315 goto clean;
316
317 /* data overrun */
318 case -EOVERFLOW:
319 dev->net->stats.rx_over_errors++;
320 /* FALLTHROUGH */
321
322 default:
323 dev->net->stats.rx_errors++;
324 DBG(dev, "rx status %d\n", status);
325 break;
326 }
327
328 if (skb)
329 dev_kfree_skb_any(skb);
330 if (!netif_running(dev->net)) {
331clean:
332 spin_lock(&dev->req_lock);
333 list_add(&req->list, &dev->rx_reqs);
334 spin_unlock(&dev->req_lock);
335 req = NULL;
336 }
337 if (req)
338 rx_submit(dev, req, GFP_ATOMIC);
339}
340
341static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
342{
343 unsigned i;
344 struct usb_request *req;
345
346 if (!n)
347 return -ENOMEM;
348
349 /* queue/recycle up to N requests */
350 i = n;
351 list_for_each_entry(req, list, list) {
352 if (i-- == 0)
353 goto extra;
354 }
355 while (i--) {
356 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
357 if (!req)
358 return list_empty(list) ? -ENOMEM : 0;
359 list_add(&req->list, list);
360 }
361 return 0;
362
363extra:
364 /* free extras */
365 for (;;) {
366 struct list_head *next;
367
368 next = req->list.next;
369 list_del(&req->list);
370 usb_ep_free_request(ep, req);
371
372 if (next == list)
373 break;
374
375 req = container_of(next, struct usb_request, list);
376 }
377 return 0;
378}
379
380static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
381{
382 int status;
383
384 spin_lock(&dev->req_lock);
385 status = prealloc(&dev->tx_reqs, link->in_ep, n);
386 if (status < 0)
387 goto fail;
388 status = prealloc(&dev->rx_reqs, link->out_ep, n);
389 if (status < 0)
390 goto fail;
391 goto done;
392fail:
393 DBG(dev, "can't alloc requests\n");
394done:
395 spin_unlock(&dev->req_lock);
396 return status;
397}
398
399static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
400{
401 struct usb_request *req;
402 unsigned long flags;
403
404 /* fill unused rxq slots with some skb */
405 spin_lock_irqsave(&dev->req_lock, flags);
406 while (!list_empty(&dev->rx_reqs)) {
407 req = container_of(dev->rx_reqs.next,
408 struct usb_request, list);
409 list_del_init(&req->list);
410 spin_unlock_irqrestore(&dev->req_lock, flags);
411
412 if (rx_submit(dev, req, gfp_flags) < 0) {
413 defer_kevent(dev, WORK_RX_MEMORY);
414 return;
415 }
416
417 spin_lock_irqsave(&dev->req_lock, flags);
418 }
419 spin_unlock_irqrestore(&dev->req_lock, flags);
420}
421
422static void eth_work(struct work_struct *work)
423{
424 struct eth_dev *dev = container_of(work, struct eth_dev, work);
425
426 if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
427 if (netif_running(dev->net))
428 rx_fill(dev, GFP_KERNEL);
429 }
430
431 if (dev->todo)
432 DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
433}
434
435static void tx_complete(struct usb_ep *ep, struct usb_request *req)
436{
437 struct sk_buff *skb = req->context;
438 struct eth_dev *dev = ep->driver_data;
439
440 switch (req->status) {
441 default:
442 dev->net->stats.tx_errors++;
443 VDBG(dev, "tx err %d\n", req->status);
444 /* FALLTHROUGH */
445 case -ECONNRESET: /* unlink */
446 case -ESHUTDOWN: /* disconnect etc */
447 break;
448 case 0:
449 dev->net->stats.tx_bytes += skb->len;
450 }
451 dev->net->stats.tx_packets++;
452
453 spin_lock(&dev->req_lock);
454 list_add(&req->list, &dev->tx_reqs);
455 spin_unlock(&dev->req_lock);
456 dev_kfree_skb_any(skb);
457
458 atomic_dec(&dev->tx_qlen);
459 if (netif_carrier_ok(dev->net))
460 netif_wake_queue(dev->net);
461}
462
463static inline int is_promisc(u16 cdc_filter)
464{
465 return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
466}
467
Stephen Hemminger25a79c42009-08-31 19:50:45 +0000468static netdev_tx_t eth_start_xmit(struct sk_buff *skb,
469 struct net_device *net)
David Brownell2b3d9422008-06-19 18:19:28 -0700470{
471 struct eth_dev *dev = netdev_priv(net);
472 int length = skb->len;
473 int retval;
474 struct usb_request *req = NULL;
475 unsigned long flags;
476 struct usb_ep *in;
477 u16 cdc_filter;
478
479 spin_lock_irqsave(&dev->lock, flags);
480 if (dev->port_usb) {
481 in = dev->port_usb->in_ep;
482 cdc_filter = dev->port_usb->cdc_filter;
483 } else {
484 in = NULL;
485 cdc_filter = 0;
486 }
487 spin_unlock_irqrestore(&dev->lock, flags);
488
489 if (!in) {
490 dev_kfree_skb_any(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000491 return NETDEV_TX_OK;
David Brownell2b3d9422008-06-19 18:19:28 -0700492 }
493
494 /* apply outgoing CDC or RNDIS filters */
495 if (!is_promisc(cdc_filter)) {
496 u8 *dest = skb->data;
497
498 if (is_multicast_ether_addr(dest)) {
499 u16 type;
500
501 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
502 * SET_ETHERNET_MULTICAST_FILTERS requests
503 */
504 if (is_broadcast_ether_addr(dest))
505 type = USB_CDC_PACKET_TYPE_BROADCAST;
506 else
507 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
508 if (!(cdc_filter & type)) {
509 dev_kfree_skb_any(skb);
Patrick McHardy6ed10652009-06-23 06:03:08 +0000510 return NETDEV_TX_OK;
David Brownell2b3d9422008-06-19 18:19:28 -0700511 }
512 }
513 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */
514 }
515
516 spin_lock_irqsave(&dev->req_lock, flags);
517 /*
518 * this freelist can be empty if an interrupt triggered disconnect()
519 * and reconfigured the gadget (shutting down this queue) after the
520 * network stack decided to xmit but before we got the spinlock.
521 */
522 if (list_empty(&dev->tx_reqs)) {
523 spin_unlock_irqrestore(&dev->req_lock, flags);
Patrick McHardy5b548142009-06-12 06:22:29 +0000524 return NETDEV_TX_BUSY;
David Brownell2b3d9422008-06-19 18:19:28 -0700525 }
526
527 req = container_of(dev->tx_reqs.next, struct usb_request, list);
528 list_del(&req->list);
529
530 /* temporarily stop TX queue when the freelist empties */
531 if (list_empty(&dev->tx_reqs))
532 netif_stop_queue(net);
533 spin_unlock_irqrestore(&dev->req_lock, flags);
534
535 /* no buffer copies needed, unless the network stack did it
536 * or the hardware can't use skb buffers.
537 * or there's not enough space for extra headers we need
538 */
539 if (dev->wrap) {
540 struct sk_buff *skb_new;
541
542 skb_new = dev->wrap(skb);
543 if (!skb_new)
544 goto drop;
545
546 dev_kfree_skb_any(skb);
547 skb = skb_new;
548 length = skb->len;
549 }
550 req->buf = skb->data;
551 req->context = skb;
552 req->complete = tx_complete;
553
554 /* use zlp framing on tx for strict CDC-Ether conformance,
555 * though any robust network rx path ignores extra padding.
556 * and some hardware doesn't like to write zlps.
557 */
558 req->zero = 1;
559 if (!dev->zlp && (length % in->maxpacket) == 0)
560 length++;
561
562 req->length = length;
563
564 /* throttle highspeed IRQ rate back slightly */
565 if (gadget_is_dualspeed(dev->gadget))
566 req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH)
567 ? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
568 : 0;
569
570 retval = usb_ep_queue(in, req, GFP_ATOMIC);
571 switch (retval) {
572 default:
573 DBG(dev, "tx queue err %d\n", retval);
574 break;
575 case 0:
576 net->trans_start = jiffies;
577 atomic_inc(&dev->tx_qlen);
578 }
579
580 if (retval) {
581drop:
582 dev->net->stats.tx_dropped++;
583 dev_kfree_skb_any(skb);
584 spin_lock_irqsave(&dev->req_lock, flags);
585 if (list_empty(&dev->tx_reqs))
586 netif_start_queue(net);
587 list_add(&req->list, &dev->tx_reqs);
588 spin_unlock_irqrestore(&dev->req_lock, flags);
589 }
Patrick McHardy6ed10652009-06-23 06:03:08 +0000590 return NETDEV_TX_OK;
David Brownell2b3d9422008-06-19 18:19:28 -0700591}
592
593/*-------------------------------------------------------------------------*/
594
595static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
596{
597 DBG(dev, "%s\n", __func__);
598
599 /* fill the rx queue */
600 rx_fill(dev, gfp_flags);
601
602 /* and open the tx floodgates */
603 atomic_set(&dev->tx_qlen, 0);
604 netif_wake_queue(dev->net);
605}
606
607static int eth_open(struct net_device *net)
608{
609 struct eth_dev *dev = netdev_priv(net);
610 struct gether *link;
611
612 DBG(dev, "%s\n", __func__);
613 if (netif_carrier_ok(dev->net))
614 eth_start(dev, GFP_KERNEL);
615
616 spin_lock_irq(&dev->lock);
617 link = dev->port_usb;
618 if (link && link->open)
619 link->open(link);
620 spin_unlock_irq(&dev->lock);
621
622 return 0;
623}
624
625static int eth_stop(struct net_device *net)
626{
627 struct eth_dev *dev = netdev_priv(net);
628 unsigned long flags;
629
630 VDBG(dev, "%s\n", __func__);
631 netif_stop_queue(net);
632
633 DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
634 dev->net->stats.rx_packets, dev->net->stats.tx_packets,
635 dev->net->stats.rx_errors, dev->net->stats.tx_errors
636 );
637
638 /* ensure there are no more active requests */
639 spin_lock_irqsave(&dev->lock, flags);
640 if (dev->port_usb) {
641 struct gether *link = dev->port_usb;
642
643 if (link->close)
644 link->close(link);
645
646 /* NOTE: we have no abort-queue primitive we could use
647 * to cancel all pending I/O. Instead, we disable then
648 * reenable the endpoints ... this idiom may leave toggle
649 * wrong, but that's a self-correcting error.
650 *
651 * REVISIT: we *COULD* just let the transfers complete at
652 * their own pace; the network stack can handle old packets.
653 * For the moment we leave this here, since it works.
654 */
655 usb_ep_disable(link->in_ep);
656 usb_ep_disable(link->out_ep);
657 if (netif_carrier_ok(net)) {
658 DBG(dev, "host still using in/out endpoints\n");
659 usb_ep_enable(link->in_ep, link->in);
660 usb_ep_enable(link->out_ep, link->out);
661 }
662 }
663 spin_unlock_irqrestore(&dev->lock, flags);
664
665 return 0;
666}
667
668/*-------------------------------------------------------------------------*/
669
670/* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
671static char *dev_addr;
672module_param(dev_addr, charp, S_IRUGO);
673MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");
674
675/* this address is invisible to ifconfig */
676static char *host_addr;
677module_param(host_addr, charp, S_IRUGO);
678MODULE_PARM_DESC(host_addr, "Host Ethernet Address");
679
680
681static u8 __init nibble(unsigned char c)
682{
683 if (isdigit(c))
684 return c - '0';
685 c = toupper(c);
686 if (isxdigit(c))
687 return 10 + c - 'A';
688 return 0;
689}
690
691static int __init get_ether_addr(const char *str, u8 *dev_addr)
692{
693 if (str) {
694 unsigned i;
695
696 for (i = 0; i < 6; i++) {
697 unsigned char num;
698
699 if ((*str == '.') || (*str == ':'))
700 str++;
701 num = nibble(*str++) << 4;
702 num |= (nibble(*str++));
703 dev_addr [i] = num;
704 }
705 if (is_valid_ether_addr(dev_addr))
706 return 0;
707 }
708 random_ether_addr(dev_addr);
709 return 1;
710}
711
712static struct eth_dev *the_dev;
713
Stephen Hemminger5ec38f32009-01-07 18:05:39 -0800714static const struct net_device_ops eth_netdev_ops = {
715 .ndo_open = eth_open,
716 .ndo_stop = eth_stop,
717 .ndo_start_xmit = eth_start_xmit,
718 .ndo_change_mtu = ueth_change_mtu,
719 .ndo_set_mac_address = eth_mac_addr,
720 .ndo_validate_addr = eth_validate_addr,
721};
David Brownell2b3d9422008-06-19 18:19:28 -0700722
723/**
724 * gether_setup - initialize one ethernet-over-usb link
725 * @g: gadget to associated with these links
726 * @ethaddr: NULL, or a buffer in which the ethernet address of the
727 * host side of the link is recorded
728 * Context: may sleep
729 *
730 * This sets up the single network link that may be exported by a
731 * gadget driver using this framework. The link layer addresses are
732 * set up using module parameters.
733 *
734 * Returns negative errno, or zero on success
735 */
736int __init gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
737{
738 struct eth_dev *dev;
739 struct net_device *net;
740 int status;
741
742 if (the_dev)
743 return -EBUSY;
744
745 net = alloc_etherdev(sizeof *dev);
746 if (!net)
747 return -ENOMEM;
748
749 dev = netdev_priv(net);
750 spin_lock_init(&dev->lock);
751 spin_lock_init(&dev->req_lock);
752 INIT_WORK(&dev->work, eth_work);
753 INIT_LIST_HEAD(&dev->tx_reqs);
754 INIT_LIST_HEAD(&dev->rx_reqs);
755
756 /* network device setup */
757 dev->net = net;
758 strcpy(net->name, "usb%d");
759
760 if (get_ether_addr(dev_addr, net->dev_addr))
761 dev_warn(&g->dev,
762 "using random %s ethernet address\n", "self");
763 if (get_ether_addr(host_addr, dev->host_mac))
764 dev_warn(&g->dev,
765 "using random %s ethernet address\n", "host");
766
767 if (ethaddr)
768 memcpy(ethaddr, dev->host_mac, ETH_ALEN);
769
Stephen Hemminger5ec38f32009-01-07 18:05:39 -0800770 net->netdev_ops = &eth_netdev_ops;
771
David Brownell2b3d9422008-06-19 18:19:28 -0700772 SET_ETHTOOL_OPS(net, &ops);
773
774 /* two kinds of host-initiated state changes:
775 * - iff DATA transfer is active, carrier is "on"
776 * - tx queueing enabled if open *and* carrier is "on"
777 */
778 netif_stop_queue(net);
779 netif_carrier_off(net);
780
781 dev->gadget = g;
782 SET_NETDEV_DEV(net, &g->dev);
783
784 status = register_netdev(net);
785 if (status < 0) {
786 dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
787 free_netdev(net);
788 } else {
Johannes Berge1749612008-10-27 15:59:26 -0700789 INFO(dev, "MAC %pM\n", net->dev_addr);
790 INFO(dev, "HOST MAC %pM\n", dev->host_mac);
David Brownell2b3d9422008-06-19 18:19:28 -0700791
792 the_dev = dev;
793 }
794
795 return status;
796}
797
798/**
799 * gether_cleanup - remove Ethernet-over-USB device
800 * Context: may sleep
801 *
802 * This is called to free all resources allocated by @gether_setup().
803 */
804void gether_cleanup(void)
805{
806 if (!the_dev)
807 return;
808
809 unregister_netdev(the_dev->net);
810 free_netdev(the_dev->net);
811
812 /* assuming we used keventd, it must quiesce too */
813 flush_scheduled_work();
814
815 the_dev = NULL;
816}
817
818
819/**
820 * gether_connect - notify network layer that USB link is active
821 * @link: the USB link, set up with endpoints, descriptors matching
822 * current device speed, and any framing wrapper(s) set up.
823 * Context: irqs blocked
824 *
825 * This is called to activate endpoints and let the network layer know
826 * the connection is active ("carrier detect"). It may cause the I/O
827 * queues to open and start letting network packets flow, but will in
828 * any case activate the endpoints so that they respond properly to the
829 * USB host.
830 *
831 * Verify net_device pointer returned using IS_ERR(). If it doesn't
832 * indicate some error code (negative errno), ep->driver_data values
833 * have been overwritten.
834 */
835struct net_device *gether_connect(struct gether *link)
836{
837 struct eth_dev *dev = the_dev;
838 int result = 0;
839
840 if (!dev)
841 return ERR_PTR(-EINVAL);
842
843 link->in_ep->driver_data = dev;
844 result = usb_ep_enable(link->in_ep, link->in);
845 if (result != 0) {
846 DBG(dev, "enable %s --> %d\n",
847 link->in_ep->name, result);
848 goto fail0;
849 }
850
851 link->out_ep->driver_data = dev;
852 result = usb_ep_enable(link->out_ep, link->out);
853 if (result != 0) {
854 DBG(dev, "enable %s --> %d\n",
855 link->out_ep->name, result);
856 goto fail1;
857 }
858
859 if (result == 0)
860 result = alloc_requests(dev, link, qlen(dev->gadget));
861
862 if (result == 0) {
863 dev->zlp = link->is_zlp_ok;
864 DBG(dev, "qlen %d\n", qlen(dev->gadget));
865
866 dev->header_len = link->header_len;
867 dev->unwrap = link->unwrap;
868 dev->wrap = link->wrap;
869
870 spin_lock(&dev->lock);
871 dev->port_usb = link;
872 link->ioport = dev;
David Brownell29bac7b2008-09-06 21:33:49 -0700873 if (netif_running(dev->net)) {
874 if (link->open)
875 link->open(link);
876 } else {
877 if (link->close)
878 link->close(link);
879 }
David Brownell2b3d9422008-06-19 18:19:28 -0700880 spin_unlock(&dev->lock);
881
882 netif_carrier_on(dev->net);
883 if (netif_running(dev->net))
884 eth_start(dev, GFP_ATOMIC);
885
886 /* on error, disable any endpoints */
887 } else {
888 (void) usb_ep_disable(link->out_ep);
889fail1:
890 (void) usb_ep_disable(link->in_ep);
891 }
892fail0:
893 /* caller is responsible for cleanup on error */
894 if (result < 0)
895 return ERR_PTR(result);
896 return dev->net;
897}
898
899/**
900 * gether_disconnect - notify network layer that USB link is inactive
901 * @link: the USB link, on which gether_connect() was called
902 * Context: irqs blocked
903 *
904 * This is called to deactivate endpoints and let the network layer know
905 * the connection went inactive ("no carrier").
906 *
907 * On return, the state is as if gether_connect() had never been called.
908 * The endpoints are inactive, and accordingly without active USB I/O.
909 * Pointers to endpoint descriptors and endpoint private data are nulled.
910 */
911void gether_disconnect(struct gether *link)
912{
913 struct eth_dev *dev = link->ioport;
914 struct usb_request *req;
915
916 WARN_ON(!dev);
917 if (!dev)
918 return;
919
920 DBG(dev, "%s\n", __func__);
921
922 netif_stop_queue(dev->net);
923 netif_carrier_off(dev->net);
924
925 /* disable endpoints, forcing (synchronous) completion
926 * of all pending i/o. then free the request objects
927 * and forget about the endpoints.
928 */
929 usb_ep_disable(link->in_ep);
930 spin_lock(&dev->req_lock);
931 while (!list_empty(&dev->tx_reqs)) {
932 req = container_of(dev->tx_reqs.next,
933 struct usb_request, list);
934 list_del(&req->list);
935
936 spin_unlock(&dev->req_lock);
937 usb_ep_free_request(link->in_ep, req);
938 spin_lock(&dev->req_lock);
939 }
940 spin_unlock(&dev->req_lock);
941 link->in_ep->driver_data = NULL;
942 link->in = NULL;
943
944 usb_ep_disable(link->out_ep);
945 spin_lock(&dev->req_lock);
946 while (!list_empty(&dev->rx_reqs)) {
947 req = container_of(dev->rx_reqs.next,
948 struct usb_request, list);
949 list_del(&req->list);
950
951 spin_unlock(&dev->req_lock);
952 usb_ep_free_request(link->out_ep, req);
953 spin_lock(&dev->req_lock);
954 }
955 spin_unlock(&dev->req_lock);
956 link->out_ep->driver_data = NULL;
957 link->out = NULL;
958
959 /* finish forgetting about this USB link episode */
960 dev->header_len = 0;
961 dev->unwrap = NULL;
962 dev->wrap = NULL;
963
964 spin_lock(&dev->lock);
965 dev->port_usb = NULL;
966 link->ioport = NULL;
967 spin_unlock(&dev->lock);
968}