Commit | Line | Data |
---|---|---|
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> | |
2b3d942c DB |
26 | #include <linux/device.h> |
27 | #include <linux/ctype.h> | |
28 | #include <linux/etherdevice.h> | |
29 | #include <linux/ethtool.h> | |
30 | ||
31 | #include "u_ether.h" | |
32 | ||
33 | ||
34 | /* | |
35 | * This component encapsulates the Ethernet link glue needed to provide | |
36 | * one (!) network link through the USB gadget stack, normally "usb0". | |
37 | * | |
38 | * The control and data models are handled by the function driver which | |
9b39e9dd BN |
39 | * connects to this code; such as CDC Ethernet (ECM or EEM), |
40 | * "CDC Subset", or RNDIS. That includes all descriptor and endpoint | |
41 | * management. | |
2b3d942c DB |
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 | ||
9b39e9dd BN |
71 | struct sk_buff_head rx_frames; |
72 | ||
2b3d942c | 73 | unsigned header_len; |
9b39e9dd BN |
74 | struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb); |
75 | int (*unwrap)(struct gether *, | |
76 | struct sk_buff *skb, | |
77 | struct sk_buff_head *list); | |
2b3d942c DB |
78 | |
79 | struct work_struct work; | |
80 | ||
81 | unsigned long todo; | |
82 | #define WORK_RX_MEMORY 0 | |
83 | ||
84 | bool zlp; | |
85 | u8 host_mac[ETH_ALEN]; | |
86 | }; | |
87 | ||
88 | /*-------------------------------------------------------------------------*/ | |
89 | ||
90 | #define RX_EXTRA 20 /* bytes guarding against rx overflows */ | |
91 | ||
92 | #define DEFAULT_QLEN 2 /* double buffering by default */ | |
93 | ||
94 | ||
95 | #ifdef CONFIG_USB_GADGET_DUALSPEED | |
96 | ||
97 | static unsigned qmult = 5; | |
98 | module_param(qmult, uint, S_IRUGO|S_IWUSR); | |
99 | MODULE_PARM_DESC(qmult, "queue length multiplier at high speed"); | |
100 | ||
101 | #else /* full speed (low speed doesn't do bulk) */ | |
102 | #define qmult 1 | |
103 | #endif | |
104 | ||
105 | /* for dual-speed hardware, use deeper queues at highspeed */ | |
106 | static inline int qlen(struct usb_gadget *gadget) | |
107 | { | |
108 | if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH) | |
109 | return qmult * DEFAULT_QLEN; | |
110 | else | |
111 | return DEFAULT_QLEN; | |
112 | } | |
113 | ||
114 | /*-------------------------------------------------------------------------*/ | |
115 | ||
116 | /* REVISIT there must be a better way than having two sets | |
117 | * of debug calls ... | |
118 | */ | |
119 | ||
120 | #undef DBG | |
121 | #undef VDBG | |
122 | #undef ERROR | |
2b3d942c DB |
123 | #undef INFO |
124 | ||
125 | #define xprintk(d, level, fmt, args...) \ | |
126 | printk(level "%s: " fmt , (d)->net->name , ## args) | |
127 | ||
128 | #ifdef DEBUG | |
129 | #undef DEBUG | |
130 | #define DBG(dev, fmt, args...) \ | |
131 | xprintk(dev , KERN_DEBUG , fmt , ## args) | |
132 | #else | |
133 | #define DBG(dev, fmt, args...) \ | |
134 | do { } while (0) | |
135 | #endif /* DEBUG */ | |
136 | ||
137 | #ifdef VERBOSE_DEBUG | |
138 | #define VDBG DBG | |
139 | #else | |
140 | #define VDBG(dev, fmt, args...) \ | |
141 | do { } while (0) | |
142 | #endif /* DEBUG */ | |
143 | ||
144 | #define ERROR(dev, fmt, args...) \ | |
145 | xprintk(dev , KERN_ERR , fmt , ## args) | |
2b3d942c DB |
146 | #define INFO(dev, fmt, args...) \ |
147 | xprintk(dev , KERN_INFO , fmt , ## args) | |
148 | ||
149 | /*-------------------------------------------------------------------------*/ | |
150 | ||
151 | /* NETWORK DRIVER HOOKUP (to the layer above this driver) */ | |
152 | ||
ccad637b | 153 | static int ueth_change_mtu(struct net_device *net, int new_mtu) |
2b3d942c DB |
154 | { |
155 | struct eth_dev *dev = netdev_priv(net); | |
156 | unsigned long flags; | |
157 | int status = 0; | |
158 | ||
159 | /* don't change MTU on "live" link (peer won't know) */ | |
160 | spin_lock_irqsave(&dev->lock, flags); | |
161 | if (dev->port_usb) | |
162 | status = -EBUSY; | |
163 | else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN) | |
164 | status = -ERANGE; | |
165 | else | |
166 | net->mtu = new_mtu; | |
167 | spin_unlock_irqrestore(&dev->lock, flags); | |
168 | ||
169 | return status; | |
170 | } | |
171 | ||
172 | static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p) | |
173 | { | |
174 | struct eth_dev *dev = netdev_priv(net); | |
175 | ||
176 | strlcpy(p->driver, "g_ether", sizeof p->driver); | |
8a1ce2c0 | 177 | strlcpy(p->version, UETH__VERSION, sizeof p->version); |
2b3d942c DB |
178 | strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version); |
179 | strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info); | |
180 | } | |
181 | ||
2b3d942c DB |
182 | /* REVISIT can also support: |
183 | * - WOL (by tracking suspends and issuing remote wakeup) | |
184 | * - msglevel (implies updated messaging) | |
185 | * - ... probably more ethtool ops | |
186 | */ | |
187 | ||
0fc0b732 | 188 | static const struct ethtool_ops ops = { |
2b3d942c | 189 | .get_drvinfo = eth_get_drvinfo, |
237e75bf | 190 | .get_link = ethtool_op_get_link, |
2b3d942c DB |
191 | }; |
192 | ||
193 | static void defer_kevent(struct eth_dev *dev, int flag) | |
194 | { | |
195 | if (test_and_set_bit(flag, &dev->todo)) | |
196 | return; | |
197 | if (!schedule_work(&dev->work)) | |
198 | ERROR(dev, "kevent %d may have been dropped\n", flag); | |
199 | else | |
200 | DBG(dev, "kevent %d scheduled\n", flag); | |
201 | } | |
202 | ||
203 | static void rx_complete(struct usb_ep *ep, struct usb_request *req); | |
204 | ||
205 | static int | |
206 | rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags) | |
207 | { | |
208 | struct sk_buff *skb; | |
209 | int retval = -ENOMEM; | |
210 | size_t size = 0; | |
211 | struct usb_ep *out; | |
212 | unsigned long flags; | |
213 | ||
214 | spin_lock_irqsave(&dev->lock, flags); | |
215 | if (dev->port_usb) | |
216 | out = dev->port_usb->out_ep; | |
217 | else | |
218 | out = NULL; | |
219 | spin_unlock_irqrestore(&dev->lock, flags); | |
220 | ||
221 | if (!out) | |
222 | return -ENOTCONN; | |
223 | ||
224 | ||
225 | /* Padding up to RX_EXTRA handles minor disagreements with host. | |
226 | * Normally we use the USB "terminate on short read" convention; | |
227 | * so allow up to (N*maxpacket), since that memory is normally | |
228 | * already allocated. Some hardware doesn't deal well with short | |
229 | * reads (e.g. DMA must be N*maxpacket), so for now don't trim a | |
230 | * byte off the end (to force hardware errors on overflow). | |
231 | * | |
232 | * RNDIS uses internal framing, and explicitly allows senders to | |
233 | * pad to end-of-packet. That's potentially nice for speed, but | |
234 | * means receivers can't recover lost synch on their own (because | |
235 | * new packets don't only start after a short RX). | |
236 | */ | |
237 | size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA; | |
238 | size += dev->port_usb->header_len; | |
239 | size += out->maxpacket - 1; | |
240 | size -= size % out->maxpacket; | |
241 | ||
242 | skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags); | |
243 | if (skb == NULL) { | |
244 | DBG(dev, "no rx skb\n"); | |
245 | goto enomem; | |
246 | } | |
247 | ||
248 | /* Some platforms perform better when IP packets are aligned, | |
249 | * but on at least one, checksumming fails otherwise. Note: | |
250 | * RNDIS headers involve variable numbers of LE32 values. | |
251 | */ | |
252 | skb_reserve(skb, NET_IP_ALIGN); | |
253 | ||
254 | req->buf = skb->data; | |
255 | req->length = size; | |
256 | req->complete = rx_complete; | |
257 | req->context = skb; | |
258 | ||
259 | retval = usb_ep_queue(out, req, gfp_flags); | |
260 | if (retval == -ENOMEM) | |
261 | enomem: | |
262 | defer_kevent(dev, WORK_RX_MEMORY); | |
263 | if (retval) { | |
264 | DBG(dev, "rx submit --> %d\n", retval); | |
265 | if (skb) | |
266 | dev_kfree_skb_any(skb); | |
267 | spin_lock_irqsave(&dev->req_lock, flags); | |
268 | list_add(&req->list, &dev->rx_reqs); | |
269 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
270 | } | |
271 | return retval; | |
272 | } | |
273 | ||
274 | static void rx_complete(struct usb_ep *ep, struct usb_request *req) | |
275 | { | |
9b39e9dd | 276 | struct sk_buff *skb = req->context, *skb2; |
2b3d942c DB |
277 | struct eth_dev *dev = ep->driver_data; |
278 | int status = req->status; | |
279 | ||
280 | switch (status) { | |
281 | ||
282 | /* normal completion */ | |
283 | case 0: | |
284 | skb_put(skb, req->actual); | |
2b3d942c | 285 | |
9b39e9dd BN |
286 | if (dev->unwrap) { |
287 | unsigned long flags; | |
2b3d942c | 288 | |
9b39e9dd BN |
289 | spin_lock_irqsave(&dev->lock, flags); |
290 | if (dev->port_usb) { | |
291 | status = dev->unwrap(dev->port_usb, | |
292 | skb, | |
293 | &dev->rx_frames); | |
294 | } else { | |
295 | dev_kfree_skb_any(skb); | |
296 | status = -ENOTCONN; | |
297 | } | |
298 | spin_unlock_irqrestore(&dev->lock, flags); | |
299 | } else { | |
300 | skb_queue_tail(&dev->rx_frames, skb); | |
301 | } | |
2b3d942c | 302 | skb = NULL; |
9b39e9dd BN |
303 | |
304 | skb2 = skb_dequeue(&dev->rx_frames); | |
305 | while (skb2) { | |
306 | if (status < 0 | |
307 | || ETH_HLEN > skb2->len | |
308 | || skb2->len > ETH_FRAME_LEN) { | |
309 | dev->net->stats.rx_errors++; | |
310 | dev->net->stats.rx_length_errors++; | |
311 | DBG(dev, "rx length %d\n", skb2->len); | |
312 | dev_kfree_skb_any(skb2); | |
313 | goto next_frame; | |
314 | } | |
315 | skb2->protocol = eth_type_trans(skb2, dev->net); | |
316 | dev->net->stats.rx_packets++; | |
317 | dev->net->stats.rx_bytes += skb2->len; | |
318 | ||
319 | /* no buffer copies needed, unless hardware can't | |
320 | * use skb buffers. | |
321 | */ | |
322 | status = netif_rx(skb2); | |
323 | next_frame: | |
324 | skb2 = skb_dequeue(&dev->rx_frames); | |
325 | } | |
2b3d942c DB |
326 | break; |
327 | ||
328 | /* software-driven interface shutdown */ | |
329 | case -ECONNRESET: /* unlink */ | |
330 | case -ESHUTDOWN: /* disconnect etc */ | |
331 | VDBG(dev, "rx shutdown, code %d\n", status); | |
332 | goto quiesce; | |
333 | ||
334 | /* for hardware automagic (such as pxa) */ | |
335 | case -ECONNABORTED: /* endpoint reset */ | |
336 | DBG(dev, "rx %s reset\n", ep->name); | |
337 | defer_kevent(dev, WORK_RX_MEMORY); | |
338 | quiesce: | |
339 | dev_kfree_skb_any(skb); | |
340 | goto clean; | |
341 | ||
342 | /* data overrun */ | |
343 | case -EOVERFLOW: | |
344 | dev->net->stats.rx_over_errors++; | |
345 | /* FALLTHROUGH */ | |
346 | ||
347 | default: | |
348 | dev->net->stats.rx_errors++; | |
349 | DBG(dev, "rx status %d\n", status); | |
350 | break; | |
351 | } | |
352 | ||
353 | if (skb) | |
354 | dev_kfree_skb_any(skb); | |
355 | if (!netif_running(dev->net)) { | |
356 | clean: | |
357 | spin_lock(&dev->req_lock); | |
358 | list_add(&req->list, &dev->rx_reqs); | |
359 | spin_unlock(&dev->req_lock); | |
360 | req = NULL; | |
361 | } | |
362 | if (req) | |
363 | rx_submit(dev, req, GFP_ATOMIC); | |
364 | } | |
365 | ||
366 | static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n) | |
367 | { | |
368 | unsigned i; | |
369 | struct usb_request *req; | |
370 | ||
371 | if (!n) | |
372 | return -ENOMEM; | |
373 | ||
374 | /* queue/recycle up to N requests */ | |
375 | i = n; | |
376 | list_for_each_entry(req, list, list) { | |
377 | if (i-- == 0) | |
378 | goto extra; | |
379 | } | |
380 | while (i--) { | |
381 | req = usb_ep_alloc_request(ep, GFP_ATOMIC); | |
382 | if (!req) | |
383 | return list_empty(list) ? -ENOMEM : 0; | |
384 | list_add(&req->list, list); | |
385 | } | |
386 | return 0; | |
387 | ||
388 | extra: | |
389 | /* free extras */ | |
390 | for (;;) { | |
391 | struct list_head *next; | |
392 | ||
393 | next = req->list.next; | |
394 | list_del(&req->list); | |
395 | usb_ep_free_request(ep, req); | |
396 | ||
397 | if (next == list) | |
398 | break; | |
399 | ||
400 | req = container_of(next, struct usb_request, list); | |
401 | } | |
402 | return 0; | |
403 | } | |
404 | ||
405 | static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n) | |
406 | { | |
407 | int status; | |
408 | ||
409 | spin_lock(&dev->req_lock); | |
410 | status = prealloc(&dev->tx_reqs, link->in_ep, n); | |
411 | if (status < 0) | |
412 | goto fail; | |
413 | status = prealloc(&dev->rx_reqs, link->out_ep, n); | |
414 | if (status < 0) | |
415 | goto fail; | |
416 | goto done; | |
417 | fail: | |
418 | DBG(dev, "can't alloc requests\n"); | |
419 | done: | |
420 | spin_unlock(&dev->req_lock); | |
421 | return status; | |
422 | } | |
423 | ||
424 | static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags) | |
425 | { | |
426 | struct usb_request *req; | |
427 | unsigned long flags; | |
428 | ||
429 | /* fill unused rxq slots with some skb */ | |
430 | spin_lock_irqsave(&dev->req_lock, flags); | |
431 | while (!list_empty(&dev->rx_reqs)) { | |
432 | req = container_of(dev->rx_reqs.next, | |
433 | struct usb_request, list); | |
434 | list_del_init(&req->list); | |
435 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
436 | ||
437 | if (rx_submit(dev, req, gfp_flags) < 0) { | |
438 | defer_kevent(dev, WORK_RX_MEMORY); | |
439 | return; | |
440 | } | |
441 | ||
442 | spin_lock_irqsave(&dev->req_lock, flags); | |
443 | } | |
444 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
445 | } | |
446 | ||
447 | static void eth_work(struct work_struct *work) | |
448 | { | |
449 | struct eth_dev *dev = container_of(work, struct eth_dev, work); | |
450 | ||
451 | if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) { | |
452 | if (netif_running(dev->net)) | |
453 | rx_fill(dev, GFP_KERNEL); | |
454 | } | |
455 | ||
456 | if (dev->todo) | |
457 | DBG(dev, "work done, flags = 0x%lx\n", dev->todo); | |
458 | } | |
459 | ||
460 | static void tx_complete(struct usb_ep *ep, struct usb_request *req) | |
461 | { | |
462 | struct sk_buff *skb = req->context; | |
463 | struct eth_dev *dev = ep->driver_data; | |
464 | ||
465 | switch (req->status) { | |
466 | default: | |
467 | dev->net->stats.tx_errors++; | |
468 | VDBG(dev, "tx err %d\n", req->status); | |
469 | /* FALLTHROUGH */ | |
470 | case -ECONNRESET: /* unlink */ | |
471 | case -ESHUTDOWN: /* disconnect etc */ | |
472 | break; | |
473 | case 0: | |
474 | dev->net->stats.tx_bytes += skb->len; | |
475 | } | |
476 | dev->net->stats.tx_packets++; | |
477 | ||
478 | spin_lock(&dev->req_lock); | |
479 | list_add(&req->list, &dev->tx_reqs); | |
480 | spin_unlock(&dev->req_lock); | |
481 | dev_kfree_skb_any(skb); | |
482 | ||
483 | atomic_dec(&dev->tx_qlen); | |
484 | if (netif_carrier_ok(dev->net)) | |
485 | netif_wake_queue(dev->net); | |
486 | } | |
487 | ||
488 | static inline int is_promisc(u16 cdc_filter) | |
489 | { | |
490 | return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; | |
491 | } | |
492 | ||
25a79c41 SH |
493 | static netdev_tx_t eth_start_xmit(struct sk_buff *skb, |
494 | struct net_device *net) | |
2b3d942c DB |
495 | { |
496 | struct eth_dev *dev = netdev_priv(net); | |
497 | int length = skb->len; | |
498 | int retval; | |
499 | struct usb_request *req = NULL; | |
500 | unsigned long flags; | |
501 | struct usb_ep *in; | |
502 | u16 cdc_filter; | |
503 | ||
504 | spin_lock_irqsave(&dev->lock, flags); | |
505 | if (dev->port_usb) { | |
506 | in = dev->port_usb->in_ep; | |
507 | cdc_filter = dev->port_usb->cdc_filter; | |
508 | } else { | |
509 | in = NULL; | |
510 | cdc_filter = 0; | |
511 | } | |
512 | spin_unlock_irqrestore(&dev->lock, flags); | |
513 | ||
514 | if (!in) { | |
515 | dev_kfree_skb_any(skb); | |
6ed10654 | 516 | return NETDEV_TX_OK; |
2b3d942c DB |
517 | } |
518 | ||
519 | /* apply outgoing CDC or RNDIS filters */ | |
520 | if (!is_promisc(cdc_filter)) { | |
521 | u8 *dest = skb->data; | |
522 | ||
523 | if (is_multicast_ether_addr(dest)) { | |
524 | u16 type; | |
525 | ||
526 | /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host | |
527 | * SET_ETHERNET_MULTICAST_FILTERS requests | |
528 | */ | |
529 | if (is_broadcast_ether_addr(dest)) | |
530 | type = USB_CDC_PACKET_TYPE_BROADCAST; | |
531 | else | |
532 | type = USB_CDC_PACKET_TYPE_ALL_MULTICAST; | |
533 | if (!(cdc_filter & type)) { | |
534 | dev_kfree_skb_any(skb); | |
6ed10654 | 535 | return NETDEV_TX_OK; |
2b3d942c DB |
536 | } |
537 | } | |
538 | /* ignores USB_CDC_PACKET_TYPE_DIRECTED */ | |
539 | } | |
540 | ||
541 | spin_lock_irqsave(&dev->req_lock, flags); | |
542 | /* | |
543 | * this freelist can be empty if an interrupt triggered disconnect() | |
544 | * and reconfigured the gadget (shutting down this queue) after the | |
545 | * network stack decided to xmit but before we got the spinlock. | |
546 | */ | |
547 | if (list_empty(&dev->tx_reqs)) { | |
548 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
5b548140 | 549 | return NETDEV_TX_BUSY; |
2b3d942c DB |
550 | } |
551 | ||
552 | req = container_of(dev->tx_reqs.next, struct usb_request, list); | |
553 | list_del(&req->list); | |
554 | ||
555 | /* temporarily stop TX queue when the freelist empties */ | |
556 | if (list_empty(&dev->tx_reqs)) | |
557 | netif_stop_queue(net); | |
558 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
559 | ||
560 | /* no buffer copies needed, unless the network stack did it | |
561 | * or the hardware can't use skb buffers. | |
562 | * or there's not enough space for extra headers we need | |
563 | */ | |
564 | if (dev->wrap) { | |
9b39e9dd | 565 | unsigned long flags; |
2b3d942c | 566 | |
9b39e9dd BN |
567 | spin_lock_irqsave(&dev->lock, flags); |
568 | if (dev->port_usb) | |
569 | skb = dev->wrap(dev->port_usb, skb); | |
570 | spin_unlock_irqrestore(&dev->lock, flags); | |
571 | if (!skb) | |
2b3d942c DB |
572 | goto drop; |
573 | ||
2b3d942c DB |
574 | length = skb->len; |
575 | } | |
576 | req->buf = skb->data; | |
577 | req->context = skb; | |
578 | req->complete = tx_complete; | |
579 | ||
580 | /* use zlp framing on tx for strict CDC-Ether conformance, | |
581 | * though any robust network rx path ignores extra padding. | |
582 | * and some hardware doesn't like to write zlps. | |
583 | */ | |
584 | req->zero = 1; | |
585 | if (!dev->zlp && (length % in->maxpacket) == 0) | |
586 | length++; | |
587 | ||
588 | req->length = length; | |
589 | ||
590 | /* throttle highspeed IRQ rate back slightly */ | |
591 | if (gadget_is_dualspeed(dev->gadget)) | |
592 | req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH) | |
593 | ? ((atomic_read(&dev->tx_qlen) % qmult) != 0) | |
594 | : 0; | |
595 | ||
596 | retval = usb_ep_queue(in, req, GFP_ATOMIC); | |
597 | switch (retval) { | |
598 | default: | |
599 | DBG(dev, "tx queue err %d\n", retval); | |
600 | break; | |
601 | case 0: | |
602 | net->trans_start = jiffies; | |
603 | atomic_inc(&dev->tx_qlen); | |
604 | } | |
605 | ||
606 | if (retval) { | |
9b39e9dd | 607 | dev_kfree_skb_any(skb); |
2b3d942c DB |
608 | drop: |
609 | dev->net->stats.tx_dropped++; | |
2b3d942c DB |
610 | spin_lock_irqsave(&dev->req_lock, flags); |
611 | if (list_empty(&dev->tx_reqs)) | |
612 | netif_start_queue(net); | |
613 | list_add(&req->list, &dev->tx_reqs); | |
614 | spin_unlock_irqrestore(&dev->req_lock, flags); | |
615 | } | |
6ed10654 | 616 | return NETDEV_TX_OK; |
2b3d942c DB |
617 | } |
618 | ||
619 | /*-------------------------------------------------------------------------*/ | |
620 | ||
621 | static void eth_start(struct eth_dev *dev, gfp_t gfp_flags) | |
622 | { | |
623 | DBG(dev, "%s\n", __func__); | |
624 | ||
625 | /* fill the rx queue */ | |
626 | rx_fill(dev, gfp_flags); | |
627 | ||
628 | /* and open the tx floodgates */ | |
629 | atomic_set(&dev->tx_qlen, 0); | |
630 | netif_wake_queue(dev->net); | |
631 | } | |
632 | ||
633 | static int eth_open(struct net_device *net) | |
634 | { | |
635 | struct eth_dev *dev = netdev_priv(net); | |
636 | struct gether *link; | |
637 | ||
638 | DBG(dev, "%s\n", __func__); | |
639 | if (netif_carrier_ok(dev->net)) | |
640 | eth_start(dev, GFP_KERNEL); | |
641 | ||
642 | spin_lock_irq(&dev->lock); | |
643 | link = dev->port_usb; | |
644 | if (link && link->open) | |
645 | link->open(link); | |
646 | spin_unlock_irq(&dev->lock); | |
647 | ||
648 | return 0; | |
649 | } | |
650 | ||
651 | static int eth_stop(struct net_device *net) | |
652 | { | |
653 | struct eth_dev *dev = netdev_priv(net); | |
654 | unsigned long flags; | |
655 | ||
656 | VDBG(dev, "%s\n", __func__); | |
657 | netif_stop_queue(net); | |
658 | ||
659 | DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n", | |
660 | dev->net->stats.rx_packets, dev->net->stats.tx_packets, | |
661 | dev->net->stats.rx_errors, dev->net->stats.tx_errors | |
662 | ); | |
663 | ||
664 | /* ensure there are no more active requests */ | |
665 | spin_lock_irqsave(&dev->lock, flags); | |
666 | if (dev->port_usb) { | |
667 | struct gether *link = dev->port_usb; | |
668 | ||
669 | if (link->close) | |
670 | link->close(link); | |
671 | ||
672 | /* NOTE: we have no abort-queue primitive we could use | |
673 | * to cancel all pending I/O. Instead, we disable then | |
674 | * reenable the endpoints ... this idiom may leave toggle | |
675 | * wrong, but that's a self-correcting error. | |
676 | * | |
677 | * REVISIT: we *COULD* just let the transfers complete at | |
678 | * their own pace; the network stack can handle old packets. | |
679 | * For the moment we leave this here, since it works. | |
680 | */ | |
681 | usb_ep_disable(link->in_ep); | |
682 | usb_ep_disable(link->out_ep); | |
683 | if (netif_carrier_ok(net)) { | |
684 | DBG(dev, "host still using in/out endpoints\n"); | |
685 | usb_ep_enable(link->in_ep, link->in); | |
686 | usb_ep_enable(link->out_ep, link->out); | |
687 | } | |
688 | } | |
689 | spin_unlock_irqrestore(&dev->lock, flags); | |
690 | ||
691 | return 0; | |
692 | } | |
693 | ||
694 | /*-------------------------------------------------------------------------*/ | |
695 | ||
696 | /* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */ | |
697 | static char *dev_addr; | |
698 | module_param(dev_addr, charp, S_IRUGO); | |
699 | MODULE_PARM_DESC(dev_addr, "Device Ethernet Address"); | |
700 | ||
701 | /* this address is invisible to ifconfig */ | |
702 | static char *host_addr; | |
703 | module_param(host_addr, charp, S_IRUGO); | |
704 | MODULE_PARM_DESC(host_addr, "Host Ethernet Address"); | |
705 | ||
706 | ||
707 | static u8 __init nibble(unsigned char c) | |
708 | { | |
709 | if (isdigit(c)) | |
710 | return c - '0'; | |
711 | c = toupper(c); | |
712 | if (isxdigit(c)) | |
713 | return 10 + c - 'A'; | |
714 | return 0; | |
715 | } | |
716 | ||
717 | static int __init get_ether_addr(const char *str, u8 *dev_addr) | |
718 | { | |
719 | if (str) { | |
720 | unsigned i; | |
721 | ||
722 | for (i = 0; i < 6; i++) { | |
723 | unsigned char num; | |
724 | ||
725 | if ((*str == '.') || (*str == ':')) | |
726 | str++; | |
727 | num = nibble(*str++) << 4; | |
728 | num |= (nibble(*str++)); | |
729 | dev_addr [i] = num; | |
730 | } | |
731 | if (is_valid_ether_addr(dev_addr)) | |
732 | return 0; | |
733 | } | |
734 | random_ether_addr(dev_addr); | |
735 | return 1; | |
736 | } | |
737 | ||
738 | static struct eth_dev *the_dev; | |
739 | ||
5ec38f30 SH |
740 | static const struct net_device_ops eth_netdev_ops = { |
741 | .ndo_open = eth_open, | |
742 | .ndo_stop = eth_stop, | |
743 | .ndo_start_xmit = eth_start_xmit, | |
744 | .ndo_change_mtu = ueth_change_mtu, | |
745 | .ndo_set_mac_address = eth_mac_addr, | |
746 | .ndo_validate_addr = eth_validate_addr, | |
747 | }; | |
2b3d942c DB |
748 | |
749 | /** | |
750 | * gether_setup - initialize one ethernet-over-usb link | |
751 | * @g: gadget to associated with these links | |
752 | * @ethaddr: NULL, or a buffer in which the ethernet address of the | |
753 | * host side of the link is recorded | |
754 | * Context: may sleep | |
755 | * | |
756 | * This sets up the single network link that may be exported by a | |
757 | * gadget driver using this framework. The link layer addresses are | |
758 | * set up using module parameters. | |
759 | * | |
760 | * Returns negative errno, or zero on success | |
761 | */ | |
762 | int __init gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]) | |
763 | { | |
764 | struct eth_dev *dev; | |
765 | struct net_device *net; | |
766 | int status; | |
767 | ||
768 | if (the_dev) | |
769 | return -EBUSY; | |
770 | ||
771 | net = alloc_etherdev(sizeof *dev); | |
772 | if (!net) | |
773 | return -ENOMEM; | |
774 | ||
775 | dev = netdev_priv(net); | |
776 | spin_lock_init(&dev->lock); | |
777 | spin_lock_init(&dev->req_lock); | |
778 | INIT_WORK(&dev->work, eth_work); | |
779 | INIT_LIST_HEAD(&dev->tx_reqs); | |
780 | INIT_LIST_HEAD(&dev->rx_reqs); | |
781 | ||
9b39e9dd BN |
782 | skb_queue_head_init(&dev->rx_frames); |
783 | ||
2b3d942c DB |
784 | /* network device setup */ |
785 | dev->net = net; | |
786 | strcpy(net->name, "usb%d"); | |
787 | ||
788 | if (get_ether_addr(dev_addr, net->dev_addr)) | |
789 | dev_warn(&g->dev, | |
790 | "using random %s ethernet address\n", "self"); | |
791 | if (get_ether_addr(host_addr, dev->host_mac)) | |
792 | dev_warn(&g->dev, | |
793 | "using random %s ethernet address\n", "host"); | |
794 | ||
795 | if (ethaddr) | |
796 | memcpy(ethaddr, dev->host_mac, ETH_ALEN); | |
797 | ||
5ec38f30 SH |
798 | net->netdev_ops = ð_netdev_ops; |
799 | ||
2b3d942c DB |
800 | SET_ETHTOOL_OPS(net, &ops); |
801 | ||
802 | /* two kinds of host-initiated state changes: | |
803 | * - iff DATA transfer is active, carrier is "on" | |
804 | * - tx queueing enabled if open *and* carrier is "on" | |
805 | */ | |
806 | netif_stop_queue(net); | |
807 | netif_carrier_off(net); | |
808 | ||
809 | dev->gadget = g; | |
810 | SET_NETDEV_DEV(net, &g->dev); | |
811 | ||
812 | status = register_netdev(net); | |
813 | if (status < 0) { | |
814 | dev_dbg(&g->dev, "register_netdev failed, %d\n", status); | |
815 | free_netdev(net); | |
816 | } else { | |
e174961c JB |
817 | INFO(dev, "MAC %pM\n", net->dev_addr); |
818 | INFO(dev, "HOST MAC %pM\n", dev->host_mac); | |
2b3d942c DB |
819 | |
820 | the_dev = dev; | |
821 | } | |
822 | ||
823 | return status; | |
824 | } | |
825 | ||
826 | /** | |
827 | * gether_cleanup - remove Ethernet-over-USB device | |
828 | * Context: may sleep | |
829 | * | |
830 | * This is called to free all resources allocated by @gether_setup(). | |
831 | */ | |
832 | void gether_cleanup(void) | |
833 | { | |
834 | if (!the_dev) | |
835 | return; | |
836 | ||
837 | unregister_netdev(the_dev->net); | |
838 | free_netdev(the_dev->net); | |
839 | ||
840 | /* assuming we used keventd, it must quiesce too */ | |
841 | flush_scheduled_work(); | |
842 | ||
843 | the_dev = NULL; | |
844 | } | |
845 | ||
846 | ||
847 | /** | |
848 | * gether_connect - notify network layer that USB link is active | |
849 | * @link: the USB link, set up with endpoints, descriptors matching | |
850 | * current device speed, and any framing wrapper(s) set up. | |
851 | * Context: irqs blocked | |
852 | * | |
853 | * This is called to activate endpoints and let the network layer know | |
854 | * the connection is active ("carrier detect"). It may cause the I/O | |
855 | * queues to open and start letting network packets flow, but will in | |
856 | * any case activate the endpoints so that they respond properly to the | |
857 | * USB host. | |
858 | * | |
859 | * Verify net_device pointer returned using IS_ERR(). If it doesn't | |
860 | * indicate some error code (negative errno), ep->driver_data values | |
861 | * have been overwritten. | |
862 | */ | |
863 | struct net_device *gether_connect(struct gether *link) | |
864 | { | |
865 | struct eth_dev *dev = the_dev; | |
866 | int result = 0; | |
867 | ||
868 | if (!dev) | |
869 | return ERR_PTR(-EINVAL); | |
870 | ||
871 | link->in_ep->driver_data = dev; | |
872 | result = usb_ep_enable(link->in_ep, link->in); | |
873 | if (result != 0) { | |
874 | DBG(dev, "enable %s --> %d\n", | |
875 | link->in_ep->name, result); | |
876 | goto fail0; | |
877 | } | |
878 | ||
879 | link->out_ep->driver_data = dev; | |
880 | result = usb_ep_enable(link->out_ep, link->out); | |
881 | if (result != 0) { | |
882 | DBG(dev, "enable %s --> %d\n", | |
883 | link->out_ep->name, result); | |
884 | goto fail1; | |
885 | } | |
886 | ||
887 | if (result == 0) | |
888 | result = alloc_requests(dev, link, qlen(dev->gadget)); | |
889 | ||
890 | if (result == 0) { | |
891 | dev->zlp = link->is_zlp_ok; | |
892 | DBG(dev, "qlen %d\n", qlen(dev->gadget)); | |
893 | ||
894 | dev->header_len = link->header_len; | |
895 | dev->unwrap = link->unwrap; | |
896 | dev->wrap = link->wrap; | |
897 | ||
898 | spin_lock(&dev->lock); | |
899 | dev->port_usb = link; | |
900 | link->ioport = dev; | |
29bac7b7 DB |
901 | if (netif_running(dev->net)) { |
902 | if (link->open) | |
903 | link->open(link); | |
904 | } else { | |
905 | if (link->close) | |
906 | link->close(link); | |
907 | } | |
2b3d942c DB |
908 | spin_unlock(&dev->lock); |
909 | ||
910 | netif_carrier_on(dev->net); | |
911 | if (netif_running(dev->net)) | |
912 | eth_start(dev, GFP_ATOMIC); | |
913 | ||
914 | /* on error, disable any endpoints */ | |
915 | } else { | |
916 | (void) usb_ep_disable(link->out_ep); | |
917 | fail1: | |
918 | (void) usb_ep_disable(link->in_ep); | |
919 | } | |
920 | fail0: | |
921 | /* caller is responsible for cleanup on error */ | |
922 | if (result < 0) | |
923 | return ERR_PTR(result); | |
924 | return dev->net; | |
925 | } | |
926 | ||
927 | /** | |
928 | * gether_disconnect - notify network layer that USB link is inactive | |
929 | * @link: the USB link, on which gether_connect() was called | |
930 | * Context: irqs blocked | |
931 | * | |
932 | * This is called to deactivate endpoints and let the network layer know | |
933 | * the connection went inactive ("no carrier"). | |
934 | * | |
935 | * On return, the state is as if gether_connect() had never been called. | |
936 | * The endpoints are inactive, and accordingly without active USB I/O. | |
937 | * Pointers to endpoint descriptors and endpoint private data are nulled. | |
938 | */ | |
939 | void gether_disconnect(struct gether *link) | |
940 | { | |
941 | struct eth_dev *dev = link->ioport; | |
942 | struct usb_request *req; | |
943 | ||
944 | WARN_ON(!dev); | |
945 | if (!dev) | |
946 | return; | |
947 | ||
948 | DBG(dev, "%s\n", __func__); | |
949 | ||
950 | netif_stop_queue(dev->net); | |
951 | netif_carrier_off(dev->net); | |
952 | ||
953 | /* disable endpoints, forcing (synchronous) completion | |
954 | * of all pending i/o. then free the request objects | |
955 | * and forget about the endpoints. | |
956 | */ | |
957 | usb_ep_disable(link->in_ep); | |
958 | spin_lock(&dev->req_lock); | |
959 | while (!list_empty(&dev->tx_reqs)) { | |
960 | req = container_of(dev->tx_reqs.next, | |
961 | struct usb_request, list); | |
962 | list_del(&req->list); | |
963 | ||
964 | spin_unlock(&dev->req_lock); | |
965 | usb_ep_free_request(link->in_ep, req); | |
966 | spin_lock(&dev->req_lock); | |
967 | } | |
968 | spin_unlock(&dev->req_lock); | |
969 | link->in_ep->driver_data = NULL; | |
970 | link->in = NULL; | |
971 | ||
972 | usb_ep_disable(link->out_ep); | |
973 | spin_lock(&dev->req_lock); | |
974 | while (!list_empty(&dev->rx_reqs)) { | |
975 | req = container_of(dev->rx_reqs.next, | |
976 | struct usb_request, list); | |
977 | list_del(&req->list); | |
978 | ||
979 | spin_unlock(&dev->req_lock); | |
980 | usb_ep_free_request(link->out_ep, req); | |
981 | spin_lock(&dev->req_lock); | |
982 | } | |
983 | spin_unlock(&dev->req_lock); | |
984 | link->out_ep->driver_data = NULL; | |
985 | link->out = NULL; | |
986 | ||
987 | /* finish forgetting about this USB link episode */ | |
988 | dev->header_len = 0; | |
989 | dev->unwrap = NULL; | |
990 | dev->wrap = NULL; | |
991 | ||
992 | spin_lock(&dev->lock); | |
993 | dev->port_usb = NULL; | |
994 | link->ioport = NULL; | |
995 | spin_unlock(&dev->lock); | |
996 | } |