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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 | ||
178 | static u32 eth_get_link(struct net_device *net) | |
179 | { | |
180 | struct eth_dev *dev = netdev_priv(net); | |
181 | return dev->gadget->speed != USB_SPEED_UNKNOWN; | |
182 | } | |
183 | ||
184 | /* REVISIT can also support: | |
185 | * - WOL (by tracking suspends and issuing remote wakeup) | |
186 | * - msglevel (implies updated messaging) | |
187 | * - ... probably more ethtool ops | |
188 | */ | |
189 | ||
190 | static struct ethtool_ops ops = { | |
191 | .get_drvinfo = eth_get_drvinfo, | |
192 | .get_link = eth_get_link | |
193 | }; | |
194 | ||
195 | static void defer_kevent(struct eth_dev *dev, int flag) | |
196 | { | |
197 | if (test_and_set_bit(flag, &dev->todo)) | |
198 | return; | |
199 | if (!schedule_work(&dev->work)) | |
200 | ERROR(dev, "kevent %d may have been dropped\n", flag); | |
201 | else | |
202 | DBG(dev, "kevent %d scheduled\n", flag); | |
203 | } | |
204 | ||
205 | static void rx_complete(struct usb_ep *ep, struct usb_request *req); | |
206 | ||
207 | static int | |
208 | rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags) | |
209 | { | |
210 | struct sk_buff *skb; | |
211 | int retval = -ENOMEM; | |
212 | size_t size = 0; | |
213 | struct usb_ep *out; | |
214 | unsigned long flags; | |
215 | ||
216 | spin_lock_irqsave(&dev->lock, flags); | |
217 | if (dev->port_usb) | |
218 | out = dev->port_usb->out_ep; | |
219 | else | |
220 | out = NULL; | |
221 | spin_unlock_irqrestore(&dev->lock, flags); | |
222 | ||
223 | if (!out) | |
224 | return -ENOTCONN; | |
225 | ||
226 | ||
227 | /* Padding up to RX_EXTRA handles minor disagreements with host. | |
228 | * Normally we use the USB "terminate on short read" convention; | |
229 | * so allow up to (N*maxpacket), since that memory is normally | |
230 | * already allocated. Some hardware doesn't deal well with short | |
231 | * reads (e.g. DMA must be N*maxpacket), so for now don't trim a | |
232 | * byte off the end (to force hardware errors on overflow). | |
233 | * | |
234 | * RNDIS uses internal framing, and explicitly allows senders to | |
235 | * pad to end-of-packet. That's potentially nice for speed, but | |
236 | * means receivers can't recover lost synch on their own (because | |
237 | * new packets don't only start after a short RX). | |
238 | */ | |
239 | size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA; | |
240 | size += dev->port_usb->header_len; | |
241 | size += out->maxpacket - 1; | |
242 | size -= size % out->maxpacket; | |
243 | ||
244 | skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags); | |
245 | if (skb == NULL) { | |
246 | DBG(dev, "no rx skb\n"); | |
247 | goto enomem; | |
248 | } | |
249 | ||
250 | /* Some platforms perform better when IP packets are aligned, | |
251 | * but on at least one, checksumming fails otherwise. Note: | |
252 | * RNDIS headers involve variable numbers of LE32 values. | |
253 | */ | |
254 | skb_reserve(skb, NET_IP_ALIGN); | |
255 | ||
256 | req->buf = skb->data; | |
257 | req->length = size; | |
258 | req->complete = rx_complete; | |
259 | req->context = skb; | |
260 | ||
261 | retval = usb_ep_queue(out, req, gfp_flags); | |
262 | if (retval == -ENOMEM) | |
263 | enomem: | |
264 | defer_kevent(dev, WORK_RX_MEMORY); | |
265 | if (retval) { | |
266 | DBG(dev, "rx submit --> %d\n", retval); | |
267 | if (skb) | |
268 | dev_kfree_skb_any(skb); | |
269 | spin_lock_irqsave(&dev->req_lock, flags); | |
270 | list_add(&req->list, &dev->rx_reqs); | |
271 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
272 | } | |
273 | return retval; | |
274 | } | |
275 | ||
276 | static void rx_complete(struct usb_ep *ep, struct usb_request *req) | |
277 | { | |
278 | struct sk_buff *skb = req->context; | |
279 | struct eth_dev *dev = ep->driver_data; | |
280 | int status = req->status; | |
281 | ||
282 | switch (status) { | |
283 | ||
284 | /* normal completion */ | |
285 | case 0: | |
286 | skb_put(skb, req->actual); | |
287 | if (dev->unwrap) | |
288 | status = dev->unwrap(skb); | |
289 | if (status < 0 | |
290 | || ETH_HLEN > skb->len | |
291 | || skb->len > ETH_FRAME_LEN) { | |
292 | dev->net->stats.rx_errors++; | |
293 | dev->net->stats.rx_length_errors++; | |
294 | DBG(dev, "rx length %d\n", skb->len); | |
295 | break; | |
296 | } | |
297 | ||
298 | skb->protocol = eth_type_trans(skb, dev->net); | |
299 | dev->net->stats.rx_packets++; | |
300 | dev->net->stats.rx_bytes += skb->len; | |
301 | ||
302 | /* no buffer copies needed, unless hardware can't | |
303 | * use skb buffers. | |
304 | */ | |
305 | status = netif_rx(skb); | |
306 | skb = NULL; | |
307 | break; | |
308 | ||
309 | /* software-driven interface shutdown */ | |
310 | case -ECONNRESET: /* unlink */ | |
311 | case -ESHUTDOWN: /* disconnect etc */ | |
312 | VDBG(dev, "rx shutdown, code %d\n", status); | |
313 | goto quiesce; | |
314 | ||
315 | /* for hardware automagic (such as pxa) */ | |
316 | case -ECONNABORTED: /* endpoint reset */ | |
317 | DBG(dev, "rx %s reset\n", ep->name); | |
318 | defer_kevent(dev, WORK_RX_MEMORY); | |
319 | quiesce: | |
320 | dev_kfree_skb_any(skb); | |
321 | goto clean; | |
322 | ||
323 | /* data overrun */ | |
324 | case -EOVERFLOW: | |
325 | dev->net->stats.rx_over_errors++; | |
326 | /* FALLTHROUGH */ | |
327 | ||
328 | default: | |
329 | dev->net->stats.rx_errors++; | |
330 | DBG(dev, "rx status %d\n", status); | |
331 | break; | |
332 | } | |
333 | ||
334 | if (skb) | |
335 | dev_kfree_skb_any(skb); | |
336 | if (!netif_running(dev->net)) { | |
337 | clean: | |
338 | spin_lock(&dev->req_lock); | |
339 | list_add(&req->list, &dev->rx_reqs); | |
340 | spin_unlock(&dev->req_lock); | |
341 | req = NULL; | |
342 | } | |
343 | if (req) | |
344 | rx_submit(dev, req, GFP_ATOMIC); | |
345 | } | |
346 | ||
347 | static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n) | |
348 | { | |
349 | unsigned i; | |
350 | struct usb_request *req; | |
351 | ||
352 | if (!n) | |
353 | return -ENOMEM; | |
354 | ||
355 | /* queue/recycle up to N requests */ | |
356 | i = n; | |
357 | list_for_each_entry(req, list, list) { | |
358 | if (i-- == 0) | |
359 | goto extra; | |
360 | } | |
361 | while (i--) { | |
362 | req = usb_ep_alloc_request(ep, GFP_ATOMIC); | |
363 | if (!req) | |
364 | return list_empty(list) ? -ENOMEM : 0; | |
365 | list_add(&req->list, list); | |
366 | } | |
367 | return 0; | |
368 | ||
369 | extra: | |
370 | /* free extras */ | |
371 | for (;;) { | |
372 | struct list_head *next; | |
373 | ||
374 | next = req->list.next; | |
375 | list_del(&req->list); | |
376 | usb_ep_free_request(ep, req); | |
377 | ||
378 | if (next == list) | |
379 | break; | |
380 | ||
381 | req = container_of(next, struct usb_request, list); | |
382 | } | |
383 | return 0; | |
384 | } | |
385 | ||
386 | static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n) | |
387 | { | |
388 | int status; | |
389 | ||
390 | spin_lock(&dev->req_lock); | |
391 | status = prealloc(&dev->tx_reqs, link->in_ep, n); | |
392 | if (status < 0) | |
393 | goto fail; | |
394 | status = prealloc(&dev->rx_reqs, link->out_ep, n); | |
395 | if (status < 0) | |
396 | goto fail; | |
397 | goto done; | |
398 | fail: | |
399 | DBG(dev, "can't alloc requests\n"); | |
400 | done: | |
401 | spin_unlock(&dev->req_lock); | |
402 | return status; | |
403 | } | |
404 | ||
405 | static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags) | |
406 | { | |
407 | struct usb_request *req; | |
408 | unsigned long flags; | |
409 | ||
410 | /* fill unused rxq slots with some skb */ | |
411 | spin_lock_irqsave(&dev->req_lock, flags); | |
412 | while (!list_empty(&dev->rx_reqs)) { | |
413 | req = container_of(dev->rx_reqs.next, | |
414 | struct usb_request, list); | |
415 | list_del_init(&req->list); | |
416 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
417 | ||
418 | if (rx_submit(dev, req, gfp_flags) < 0) { | |
419 | defer_kevent(dev, WORK_RX_MEMORY); | |
420 | return; | |
421 | } | |
422 | ||
423 | spin_lock_irqsave(&dev->req_lock, flags); | |
424 | } | |
425 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
426 | } | |
427 | ||
428 | static void eth_work(struct work_struct *work) | |
429 | { | |
430 | struct eth_dev *dev = container_of(work, struct eth_dev, work); | |
431 | ||
432 | if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) { | |
433 | if (netif_running(dev->net)) | |
434 | rx_fill(dev, GFP_KERNEL); | |
435 | } | |
436 | ||
437 | if (dev->todo) | |
438 | DBG(dev, "work done, flags = 0x%lx\n", dev->todo); | |
439 | } | |
440 | ||
441 | static void tx_complete(struct usb_ep *ep, struct usb_request *req) | |
442 | { | |
443 | struct sk_buff *skb = req->context; | |
444 | struct eth_dev *dev = ep->driver_data; | |
445 | ||
446 | switch (req->status) { | |
447 | default: | |
448 | dev->net->stats.tx_errors++; | |
449 | VDBG(dev, "tx err %d\n", req->status); | |
450 | /* FALLTHROUGH */ | |
451 | case -ECONNRESET: /* unlink */ | |
452 | case -ESHUTDOWN: /* disconnect etc */ | |
453 | break; | |
454 | case 0: | |
455 | dev->net->stats.tx_bytes += skb->len; | |
456 | } | |
457 | dev->net->stats.tx_packets++; | |
458 | ||
459 | spin_lock(&dev->req_lock); | |
460 | list_add(&req->list, &dev->tx_reqs); | |
461 | spin_unlock(&dev->req_lock); | |
462 | dev_kfree_skb_any(skb); | |
463 | ||
464 | atomic_dec(&dev->tx_qlen); | |
465 | if (netif_carrier_ok(dev->net)) | |
466 | netif_wake_queue(dev->net); | |
467 | } | |
468 | ||
469 | static inline int is_promisc(u16 cdc_filter) | |
470 | { | |
471 | return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; | |
472 | } | |
473 | ||
474 | static int eth_start_xmit(struct sk_buff *skb, struct net_device *net) | |
475 | { | |
476 | struct eth_dev *dev = netdev_priv(net); | |
477 | int length = skb->len; | |
478 | int retval; | |
479 | struct usb_request *req = NULL; | |
480 | unsigned long flags; | |
481 | struct usb_ep *in; | |
482 | u16 cdc_filter; | |
483 | ||
484 | spin_lock_irqsave(&dev->lock, flags); | |
485 | if (dev->port_usb) { | |
486 | in = dev->port_usb->in_ep; | |
487 | cdc_filter = dev->port_usb->cdc_filter; | |
488 | } else { | |
489 | in = NULL; | |
490 | cdc_filter = 0; | |
491 | } | |
492 | spin_unlock_irqrestore(&dev->lock, flags); | |
493 | ||
494 | if (!in) { | |
495 | dev_kfree_skb_any(skb); | |
496 | return 0; | |
497 | } | |
498 | ||
499 | /* apply outgoing CDC or RNDIS filters */ | |
500 | if (!is_promisc(cdc_filter)) { | |
501 | u8 *dest = skb->data; | |
502 | ||
503 | if (is_multicast_ether_addr(dest)) { | |
504 | u16 type; | |
505 | ||
506 | /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host | |
507 | * SET_ETHERNET_MULTICAST_FILTERS requests | |
508 | */ | |
509 | if (is_broadcast_ether_addr(dest)) | |
510 | type = USB_CDC_PACKET_TYPE_BROADCAST; | |
511 | else | |
512 | type = USB_CDC_PACKET_TYPE_ALL_MULTICAST; | |
513 | if (!(cdc_filter & type)) { | |
514 | dev_kfree_skb_any(skb); | |
515 | return 0; | |
516 | } | |
517 | } | |
518 | /* ignores USB_CDC_PACKET_TYPE_DIRECTED */ | |
519 | } | |
520 | ||
521 | spin_lock_irqsave(&dev->req_lock, flags); | |
522 | /* | |
523 | * this freelist can be empty if an interrupt triggered disconnect() | |
524 | * and reconfigured the gadget (shutting down this queue) after the | |
525 | * network stack decided to xmit but before we got the spinlock. | |
526 | */ | |
527 | if (list_empty(&dev->tx_reqs)) { | |
528 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
529 | return 1; | |
530 | } | |
531 | ||
532 | req = container_of(dev->tx_reqs.next, struct usb_request, list); | |
533 | list_del(&req->list); | |
534 | ||
535 | /* temporarily stop TX queue when the freelist empties */ | |
536 | if (list_empty(&dev->tx_reqs)) | |
537 | netif_stop_queue(net); | |
538 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
539 | ||
540 | /* no buffer copies needed, unless the network stack did it | |
541 | * or the hardware can't use skb buffers. | |
542 | * or there's not enough space for extra headers we need | |
543 | */ | |
544 | if (dev->wrap) { | |
545 | struct sk_buff *skb_new; | |
546 | ||
547 | skb_new = dev->wrap(skb); | |
548 | if (!skb_new) | |
549 | goto drop; | |
550 | ||
551 | dev_kfree_skb_any(skb); | |
552 | skb = skb_new; | |
553 | length = skb->len; | |
554 | } | |
555 | req->buf = skb->data; | |
556 | req->context = skb; | |
557 | req->complete = tx_complete; | |
558 | ||
559 | /* use zlp framing on tx for strict CDC-Ether conformance, | |
560 | * though any robust network rx path ignores extra padding. | |
561 | * and some hardware doesn't like to write zlps. | |
562 | */ | |
563 | req->zero = 1; | |
564 | if (!dev->zlp && (length % in->maxpacket) == 0) | |
565 | length++; | |
566 | ||
567 | req->length = length; | |
568 | ||
569 | /* throttle highspeed IRQ rate back slightly */ | |
570 | if (gadget_is_dualspeed(dev->gadget)) | |
571 | req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH) | |
572 | ? ((atomic_read(&dev->tx_qlen) % qmult) != 0) | |
573 | : 0; | |
574 | ||
575 | retval = usb_ep_queue(in, req, GFP_ATOMIC); | |
576 | switch (retval) { | |
577 | default: | |
578 | DBG(dev, "tx queue err %d\n", retval); | |
579 | break; | |
580 | case 0: | |
581 | net->trans_start = jiffies; | |
582 | atomic_inc(&dev->tx_qlen); | |
583 | } | |
584 | ||
585 | if (retval) { | |
586 | drop: | |
587 | dev->net->stats.tx_dropped++; | |
588 | dev_kfree_skb_any(skb); | |
589 | spin_lock_irqsave(&dev->req_lock, flags); | |
590 | if (list_empty(&dev->tx_reqs)) | |
591 | netif_start_queue(net); | |
592 | list_add(&req->list, &dev->tx_reqs); | |
593 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
594 | } | |
595 | return 0; | |
596 | } | |
597 | ||
598 | /*-------------------------------------------------------------------------*/ | |
599 | ||
600 | static void eth_start(struct eth_dev *dev, gfp_t gfp_flags) | |
601 | { | |
602 | DBG(dev, "%s\n", __func__); | |
603 | ||
604 | /* fill the rx queue */ | |
605 | rx_fill(dev, gfp_flags); | |
606 | ||
607 | /* and open the tx floodgates */ | |
608 | atomic_set(&dev->tx_qlen, 0); | |
609 | netif_wake_queue(dev->net); | |
610 | } | |
611 | ||
612 | static int eth_open(struct net_device *net) | |
613 | { | |
614 | struct eth_dev *dev = netdev_priv(net); | |
615 | struct gether *link; | |
616 | ||
617 | DBG(dev, "%s\n", __func__); | |
618 | if (netif_carrier_ok(dev->net)) | |
619 | eth_start(dev, GFP_KERNEL); | |
620 | ||
621 | spin_lock_irq(&dev->lock); | |
622 | link = dev->port_usb; | |
623 | if (link && link->open) | |
624 | link->open(link); | |
625 | spin_unlock_irq(&dev->lock); | |
626 | ||
627 | return 0; | |
628 | } | |
629 | ||
630 | static int eth_stop(struct net_device *net) | |
631 | { | |
632 | struct eth_dev *dev = netdev_priv(net); | |
633 | unsigned long flags; | |
634 | ||
635 | VDBG(dev, "%s\n", __func__); | |
636 | netif_stop_queue(net); | |
637 | ||
638 | DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n", | |
639 | dev->net->stats.rx_packets, dev->net->stats.tx_packets, | |
640 | dev->net->stats.rx_errors, dev->net->stats.tx_errors | |
641 | ); | |
642 | ||
643 | /* ensure there are no more active requests */ | |
644 | spin_lock_irqsave(&dev->lock, flags); | |
645 | if (dev->port_usb) { | |
646 | struct gether *link = dev->port_usb; | |
647 | ||
648 | if (link->close) | |
649 | link->close(link); | |
650 | ||
651 | /* NOTE: we have no abort-queue primitive we could use | |
652 | * to cancel all pending I/O. Instead, we disable then | |
653 | * reenable the endpoints ... this idiom may leave toggle | |
654 | * wrong, but that's a self-correcting error. | |
655 | * | |
656 | * REVISIT: we *COULD* just let the transfers complete at | |
657 | * their own pace; the network stack can handle old packets. | |
658 | * For the moment we leave this here, since it works. | |
659 | */ | |
660 | usb_ep_disable(link->in_ep); | |
661 | usb_ep_disable(link->out_ep); | |
662 | if (netif_carrier_ok(net)) { | |
663 | DBG(dev, "host still using in/out endpoints\n"); | |
664 | usb_ep_enable(link->in_ep, link->in); | |
665 | usb_ep_enable(link->out_ep, link->out); | |
666 | } | |
667 | } | |
668 | spin_unlock_irqrestore(&dev->lock, flags); | |
669 | ||
670 | return 0; | |
671 | } | |
672 | ||
673 | /*-------------------------------------------------------------------------*/ | |
674 | ||
675 | /* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */ | |
676 | static char *dev_addr; | |
677 | module_param(dev_addr, charp, S_IRUGO); | |
678 | MODULE_PARM_DESC(dev_addr, "Device Ethernet Address"); | |
679 | ||
680 | /* this address is invisible to ifconfig */ | |
681 | static char *host_addr; | |
682 | module_param(host_addr, charp, S_IRUGO); | |
683 | MODULE_PARM_DESC(host_addr, "Host Ethernet Address"); | |
684 | ||
685 | ||
686 | static u8 __init nibble(unsigned char c) | |
687 | { | |
688 | if (isdigit(c)) | |
689 | return c - '0'; | |
690 | c = toupper(c); | |
691 | if (isxdigit(c)) | |
692 | return 10 + c - 'A'; | |
693 | return 0; | |
694 | } | |
695 | ||
696 | static int __init get_ether_addr(const char *str, u8 *dev_addr) | |
697 | { | |
698 | if (str) { | |
699 | unsigned i; | |
700 | ||
701 | for (i = 0; i < 6; i++) { | |
702 | unsigned char num; | |
703 | ||
704 | if ((*str == '.') || (*str == ':')) | |
705 | str++; | |
706 | num = nibble(*str++) << 4; | |
707 | num |= (nibble(*str++)); | |
708 | dev_addr [i] = num; | |
709 | } | |
710 | if (is_valid_ether_addr(dev_addr)) | |
711 | return 0; | |
712 | } | |
713 | random_ether_addr(dev_addr); | |
714 | return 1; | |
715 | } | |
716 | ||
717 | static struct eth_dev *the_dev; | |
718 | ||
719 | ||
720 | /** | |
721 | * gether_setup - initialize one ethernet-over-usb link | |
722 | * @g: gadget to associated with these links | |
723 | * @ethaddr: NULL, or a buffer in which the ethernet address of the | |
724 | * host side of the link is recorded | |
725 | * Context: may sleep | |
726 | * | |
727 | * This sets up the single network link that may be exported by a | |
728 | * gadget driver using this framework. The link layer addresses are | |
729 | * set up using module parameters. | |
730 | * | |
731 | * Returns negative errno, or zero on success | |
732 | */ | |
733 | int __init gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]) | |
734 | { | |
735 | struct eth_dev *dev; | |
736 | struct net_device *net; | |
737 | int status; | |
738 | ||
739 | if (the_dev) | |
740 | return -EBUSY; | |
741 | ||
742 | net = alloc_etherdev(sizeof *dev); | |
743 | if (!net) | |
744 | return -ENOMEM; | |
745 | ||
746 | dev = netdev_priv(net); | |
747 | spin_lock_init(&dev->lock); | |
748 | spin_lock_init(&dev->req_lock); | |
749 | INIT_WORK(&dev->work, eth_work); | |
750 | INIT_LIST_HEAD(&dev->tx_reqs); | |
751 | INIT_LIST_HEAD(&dev->rx_reqs); | |
752 | ||
753 | /* network device setup */ | |
754 | dev->net = net; | |
755 | strcpy(net->name, "usb%d"); | |
756 | ||
757 | if (get_ether_addr(dev_addr, net->dev_addr)) | |
758 | dev_warn(&g->dev, | |
759 | "using random %s ethernet address\n", "self"); | |
760 | if (get_ether_addr(host_addr, dev->host_mac)) | |
761 | dev_warn(&g->dev, | |
762 | "using random %s ethernet address\n", "host"); | |
763 | ||
764 | if (ethaddr) | |
765 | memcpy(ethaddr, dev->host_mac, ETH_ALEN); | |
766 | ||
ccad637b | 767 | net->change_mtu = ueth_change_mtu; |
2b3d942c DB |
768 | net->hard_start_xmit = eth_start_xmit; |
769 | net->open = eth_open; | |
770 | net->stop = eth_stop; | |
771 | /* watchdog_timeo, tx_timeout ... */ | |
772 | /* set_multicast_list */ | |
773 | SET_ETHTOOL_OPS(net, &ops); | |
774 | ||
775 | /* two kinds of host-initiated state changes: | |
776 | * - iff DATA transfer is active, carrier is "on" | |
777 | * - tx queueing enabled if open *and* carrier is "on" | |
778 | */ | |
779 | netif_stop_queue(net); | |
780 | netif_carrier_off(net); | |
781 | ||
782 | dev->gadget = g; | |
783 | SET_NETDEV_DEV(net, &g->dev); | |
784 | ||
785 | status = register_netdev(net); | |
786 | if (status < 0) { | |
787 | dev_dbg(&g->dev, "register_netdev failed, %d\n", status); | |
788 | free_netdev(net); | |
789 | } else { | |
e174961c JB |
790 | INFO(dev, "MAC %pM\n", net->dev_addr); |
791 | INFO(dev, "HOST MAC %pM\n", dev->host_mac); | |
2b3d942c DB |
792 | |
793 | the_dev = dev; | |
794 | } | |
795 | ||
796 | return status; | |
797 | } | |
798 | ||
799 | /** | |
800 | * gether_cleanup - remove Ethernet-over-USB device | |
801 | * Context: may sleep | |
802 | * | |
803 | * This is called to free all resources allocated by @gether_setup(). | |
804 | */ | |
805 | void gether_cleanup(void) | |
806 | { | |
807 | if (!the_dev) | |
808 | return; | |
809 | ||
810 | unregister_netdev(the_dev->net); | |
811 | free_netdev(the_dev->net); | |
812 | ||
813 | /* assuming we used keventd, it must quiesce too */ | |
814 | flush_scheduled_work(); | |
815 | ||
816 | the_dev = NULL; | |
817 | } | |
818 | ||
819 | ||
820 | /** | |
821 | * gether_connect - notify network layer that USB link is active | |
822 | * @link: the USB link, set up with endpoints, descriptors matching | |
823 | * current device speed, and any framing wrapper(s) set up. | |
824 | * Context: irqs blocked | |
825 | * | |
826 | * This is called to activate endpoints and let the network layer know | |
827 | * the connection is active ("carrier detect"). It may cause the I/O | |
828 | * queues to open and start letting network packets flow, but will in | |
829 | * any case activate the endpoints so that they respond properly to the | |
830 | * USB host. | |
831 | * | |
832 | * Verify net_device pointer returned using IS_ERR(). If it doesn't | |
833 | * indicate some error code (negative errno), ep->driver_data values | |
834 | * have been overwritten. | |
835 | */ | |
836 | struct net_device *gether_connect(struct gether *link) | |
837 | { | |
838 | struct eth_dev *dev = the_dev; | |
839 | int result = 0; | |
840 | ||
841 | if (!dev) | |
842 | return ERR_PTR(-EINVAL); | |
843 | ||
844 | link->in_ep->driver_data = dev; | |
845 | result = usb_ep_enable(link->in_ep, link->in); | |
846 | if (result != 0) { | |
847 | DBG(dev, "enable %s --> %d\n", | |
848 | link->in_ep->name, result); | |
849 | goto fail0; | |
850 | } | |
851 | ||
852 | link->out_ep->driver_data = dev; | |
853 | result = usb_ep_enable(link->out_ep, link->out); | |
854 | if (result != 0) { | |
855 | DBG(dev, "enable %s --> %d\n", | |
856 | link->out_ep->name, result); | |
857 | goto fail1; | |
858 | } | |
859 | ||
860 | if (result == 0) | |
861 | result = alloc_requests(dev, link, qlen(dev->gadget)); | |
862 | ||
863 | if (result == 0) { | |
864 | dev->zlp = link->is_zlp_ok; | |
865 | DBG(dev, "qlen %d\n", qlen(dev->gadget)); | |
866 | ||
867 | dev->header_len = link->header_len; | |
868 | dev->unwrap = link->unwrap; | |
869 | dev->wrap = link->wrap; | |
870 | ||
871 | spin_lock(&dev->lock); | |
872 | dev->port_usb = link; | |
873 | link->ioport = dev; | |
29bac7b7 DB |
874 | if (netif_running(dev->net)) { |
875 | if (link->open) | |
876 | link->open(link); | |
877 | } else { | |
878 | if (link->close) | |
879 | link->close(link); | |
880 | } | |
2b3d942c DB |
881 | spin_unlock(&dev->lock); |
882 | ||
883 | netif_carrier_on(dev->net); | |
884 | if (netif_running(dev->net)) | |
885 | eth_start(dev, GFP_ATOMIC); | |
886 | ||
887 | /* on error, disable any endpoints */ | |
888 | } else { | |
889 | (void) usb_ep_disable(link->out_ep); | |
890 | fail1: | |
891 | (void) usb_ep_disable(link->in_ep); | |
892 | } | |
893 | fail0: | |
894 | /* caller is responsible for cleanup on error */ | |
895 | if (result < 0) | |
896 | return ERR_PTR(result); | |
897 | return dev->net; | |
898 | } | |
899 | ||
900 | /** | |
901 | * gether_disconnect - notify network layer that USB link is inactive | |
902 | * @link: the USB link, on which gether_connect() was called | |
903 | * Context: irqs blocked | |
904 | * | |
905 | * This is called to deactivate endpoints and let the network layer know | |
906 | * the connection went inactive ("no carrier"). | |
907 | * | |
908 | * On return, the state is as if gether_connect() had never been called. | |
909 | * The endpoints are inactive, and accordingly without active USB I/O. | |
910 | * Pointers to endpoint descriptors and endpoint private data are nulled. | |
911 | */ | |
912 | void gether_disconnect(struct gether *link) | |
913 | { | |
914 | struct eth_dev *dev = link->ioport; | |
915 | struct usb_request *req; | |
916 | ||
917 | WARN_ON(!dev); | |
918 | if (!dev) | |
919 | return; | |
920 | ||
921 | DBG(dev, "%s\n", __func__); | |
922 | ||
923 | netif_stop_queue(dev->net); | |
924 | netif_carrier_off(dev->net); | |
925 | ||
926 | /* disable endpoints, forcing (synchronous) completion | |
927 | * of all pending i/o. then free the request objects | |
928 | * and forget about the endpoints. | |
929 | */ | |
930 | usb_ep_disable(link->in_ep); | |
931 | spin_lock(&dev->req_lock); | |
932 | while (!list_empty(&dev->tx_reqs)) { | |
933 | req = container_of(dev->tx_reqs.next, | |
934 | struct usb_request, list); | |
935 | list_del(&req->list); | |
936 | ||
937 | spin_unlock(&dev->req_lock); | |
938 | usb_ep_free_request(link->in_ep, req); | |
939 | spin_lock(&dev->req_lock); | |
940 | } | |
941 | spin_unlock(&dev->req_lock); | |
942 | link->in_ep->driver_data = NULL; | |
943 | link->in = NULL; | |
944 | ||
945 | usb_ep_disable(link->out_ep); | |
946 | spin_lock(&dev->req_lock); | |
947 | while (!list_empty(&dev->rx_reqs)) { | |
948 | req = container_of(dev->rx_reqs.next, | |
949 | struct usb_request, list); | |
950 | list_del(&req->list); | |
951 | ||
952 | spin_unlock(&dev->req_lock); | |
953 | usb_ep_free_request(link->out_ep, req); | |
954 | spin_lock(&dev->req_lock); | |
955 | } | |
956 | spin_unlock(&dev->req_lock); | |
957 | link->out_ep->driver_data = NULL; | |
958 | link->out = NULL; | |
959 | ||
960 | /* finish forgetting about this USB link episode */ | |
961 | dev->header_len = 0; | |
962 | dev->unwrap = NULL; | |
963 | dev->wrap = NULL; | |
964 | ||
965 | spin_lock(&dev->lock); | |
966 | dev->port_usb = NULL; | |
967 | link->ioport = NULL; | |
968 | spin_unlock(&dev->lock); | |
969 | } |