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2b3d942c DB |
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 | * 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 | ||
8a1ce2c0 | 55 | #define UETH__VERSION "29-May-2008" |
2b3d942c DB |
56 | |
57 | struct 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 | ||
93 | static unsigned qmult = 5; | |
94 | module_param(qmult, uint, S_IRUGO|S_IWUSR); | |
95 | MODULE_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 */ | |
102 | static 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 | |
2b3d942c DB |
119 | #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) | |
2b3d942c DB |
142 | #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 | ||
ccad637b | 149 | static int ueth_change_mtu(struct net_device *net, int new_mtu) |
2b3d942c DB |
150 | { |
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 | ||
168 | static 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); | |
8a1ce2c0 | 173 | strlcpy(p->version, UETH__VERSION, sizeof p->version); |
2b3d942c DB |
174 | 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 | ||
2b3d942c DB |
178 | /* 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 | ||
0fc0b732 | 184 | static const struct ethtool_ops ops = { |
2b3d942c | 185 | .get_drvinfo = eth_get_drvinfo, |
237e75bf | 186 | .get_link = ethtool_op_get_link, |
2b3d942c DB |
187 | }; |
188 | ||
189 | static 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 | ||
199 | static void rx_complete(struct usb_ep *ep, struct usb_request *req); | |
200 | ||
201 | static int | |
202 | rx_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) | |
257 | enomem: | |
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 | ||
270 | static 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); | |
313 | quiesce: | |
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)) { | |
331 | clean: | |
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 | ||
341 | static 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 | ||
363 | extra: | |
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 | ||
380 | static 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; | |
392 | fail: | |
393 | DBG(dev, "can't alloc requests\n"); | |
394 | done: | |
395 | spin_unlock(&dev->req_lock); | |
396 | return status; | |
397 | } | |
398 | ||
399 | static 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 | ||
422 | static 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 | ||
435 | static 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 | ||
463 | static inline int is_promisc(u16 cdc_filter) | |
464 | { | |
465 | return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; | |
466 | } | |
467 | ||
25a79c41 SH |
468 | static netdev_tx_t eth_start_xmit(struct sk_buff *skb, |
469 | struct net_device *net) | |
2b3d942c DB |
470 | { |
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); | |
6ed10654 | 491 | return NETDEV_TX_OK; |
2b3d942c DB |
492 | } |
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); | |
6ed10654 | 510 | return NETDEV_TX_OK; |
2b3d942c DB |
511 | } |
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); | |
5b548140 | 524 | return NETDEV_TX_BUSY; |
2b3d942c DB |
525 | } |
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) { | |
581 | drop: | |
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 | } | |
6ed10654 | 590 | return NETDEV_TX_OK; |
2b3d942c DB |
591 | } |
592 | ||
593 | /*-------------------------------------------------------------------------*/ | |
594 | ||
595 | static 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 | ||
607 | static 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 | ||
625 | static 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" */ | |
671 | static char *dev_addr; | |
672 | module_param(dev_addr, charp, S_IRUGO); | |
673 | MODULE_PARM_DESC(dev_addr, "Device Ethernet Address"); | |
674 | ||
675 | /* this address is invisible to ifconfig */ | |
676 | static char *host_addr; | |
677 | module_param(host_addr, charp, S_IRUGO); | |
678 | MODULE_PARM_DESC(host_addr, "Host Ethernet Address"); | |
679 | ||
680 | ||
681 | static 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 | ||
691 | static 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 | ||
712 | static struct eth_dev *the_dev; | |
713 | ||
5ec38f30 SH |
714 | static 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 | }; | |
2b3d942c DB |
722 | |
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 | */ | |
736 | int __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 | ||
5ec38f30 SH |
770 | net->netdev_ops = ð_netdev_ops; |
771 | ||
2b3d942c DB |
772 | 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 { | |
e174961c JB |
789 | INFO(dev, "MAC %pM\n", net->dev_addr); |
790 | INFO(dev, "HOST MAC %pM\n", dev->host_mac); | |
2b3d942c DB |
791 | |
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 | */ | |
804 | void 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 | */ | |
835 | struct 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; | |
29bac7b7 DB |
873 | if (netif_running(dev->net)) { |
874 | if (link->open) | |
875 | link->open(link); | |
876 | } else { | |
877 | if (link->close) | |
878 | link->close(link); | |
879 | } | |
2b3d942c DB |
880 | 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); | |
889 | fail1: | |
890 | (void) usb_ep_disable(link->in_ep); | |
891 | } | |
892 | fail0: | |
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 | */ | |
911 | void 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 | } |