2ed2e5fb77780e2f8a46c487aecae6734aa109ac
[linux-2.6.git] / drivers / usb / net / rndis_host.c
1 /*
2  * Host Side support for RNDIS Networking Links
3  * Copyright (C) 2005 by David Brownell
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19
20 // #define      DEBUG                   // error path messages, extra info
21 // #define      VERBOSE                 // more; success messages
22
23 #include <linux/config.h>
24 #ifdef  CONFIG_USB_DEBUG
25 #   define DEBUG
26 #endif
27 #include <linux/module.h>
28 #include <linux/sched.h>
29 #include <linux/init.h>
30 #include <linux/netdevice.h>
31 #include <linux/etherdevice.h>
32 #include <linux/ethtool.h>
33 #include <linux/workqueue.h>
34 #include <linux/mii.h>
35 #include <linux/usb.h>
36 #include <linux/usb_cdc.h>
37
38 #include "usbnet.h"
39
40
41 /*
42  * RNDIS is NDIS remoted over USB.  It's a MSFT variant of CDC ACM ... of
43  * course ACM was intended for modems, not Ethernet links!  USB's standard
44  * for Ethernet links is "CDC Ethernet", which is significantly simpler.
45  */
46
47 /*
48  * CONTROL uses CDC "encapsulated commands" with funky notifications.
49  *  - control-out:  SEND_ENCAPSULATED
50  *  - interrupt-in:  RESPONSE_AVAILABLE
51  *  - control-in:  GET_ENCAPSULATED
52  *
53  * We'll try to ignore the RESPONSE_AVAILABLE notifications.
54  */
55 struct rndis_msg_hdr {
56         __le32  msg_type;                       /* RNDIS_MSG_* */
57         __le32  msg_len;
58         // followed by data that varies between messages
59         __le32  request_id;
60         __le32  status;
61         // ... and more
62 } __attribute__ ((packed));
63
64 /* RNDIS defines this (absurdly huge) control timeout */
65 #define RNDIS_CONTROL_TIMEOUT_MS        (10 * 1000)
66
67
68 #define ccpu2 __constant_cpu_to_le32
69
70 #define RNDIS_MSG_COMPLETION    ccpu2(0x80000000)
71
72 /* codes for "msg_type" field of rndis messages;
73  * only the data channel uses packet messages (maybe batched);
74  * everything else goes on the control channel.
75  */
76 #define RNDIS_MSG_PACKET        ccpu2(0x00000001)       /* 1-N packets */
77 #define RNDIS_MSG_INIT          ccpu2(0x00000002)
78 #define RNDIS_MSG_INIT_C        (RNDIS_MSG_INIT|RNDIS_MSG_COMPLETION)
79 #define RNDIS_MSG_HALT          ccpu2(0x00000003)
80 #define RNDIS_MSG_QUERY         ccpu2(0x00000004)
81 #define RNDIS_MSG_QUERY_C       (RNDIS_MSG_QUERY|RNDIS_MSG_COMPLETION)
82 #define RNDIS_MSG_SET           ccpu2(0x00000005)
83 #define RNDIS_MSG_SET_C         (RNDIS_MSG_SET|RNDIS_MSG_COMPLETION)
84 #define RNDIS_MSG_RESET         ccpu2(0x00000006)
85 #define RNDIS_MSG_RESET_C       (RNDIS_MSG_RESET|RNDIS_MSG_COMPLETION)
86 #define RNDIS_MSG_INDICATE      ccpu2(0x00000007)
87 #define RNDIS_MSG_KEEPALIVE     ccpu2(0x00000008)
88 #define RNDIS_MSG_KEEPALIVE_C   (RNDIS_MSG_KEEPALIVE|RNDIS_MSG_COMPLETION)
89
90 /* codes for "status" field of completion messages */
91 #define RNDIS_STATUS_SUCCESS            ccpu2(0x00000000)
92 #define RNDIS_STATUS_FAILURE            ccpu2(0xc0000001)
93 #define RNDIS_STATUS_INVALID_DATA       ccpu2(0xc0010015)
94 #define RNDIS_STATUS_NOT_SUPPORTED      ccpu2(0xc00000bb)
95 #define RNDIS_STATUS_MEDIA_CONNECT      ccpu2(0x4001000b)
96 #define RNDIS_STATUS_MEDIA_DISCONNECT   ccpu2(0x4001000c)
97
98
99 struct rndis_data_hdr {
100         __le32  msg_type;               /* RNDIS_MSG_PACKET */
101         __le32  msg_len;                // rndis_data_hdr + data_len + pad
102         __le32  data_offset;            // 36 -- right after header
103         __le32  data_len;               // ... real packet size
104
105         __le32  oob_data_offset;        // zero
106         __le32  oob_data_len;           // zero
107         __le32  num_oob;                // zero
108         __le32  packet_data_offset;     // zero
109
110         __le32  packet_data_len;        // zero
111         __le32  vc_handle;              // zero
112         __le32  reserved;               // zero
113 } __attribute__ ((packed));
114
115 struct rndis_init {             /* OUT */
116         // header and:
117         __le32  msg_type;                       /* RNDIS_MSG_INIT */
118         __le32  msg_len;                        // 24
119         __le32  request_id;
120         __le32  major_version;                  // of rndis (1.0)
121         __le32  minor_version;
122         __le32  max_transfer_size;
123 } __attribute__ ((packed));
124
125 struct rndis_init_c {           /* IN */
126         // header and:
127         __le32  msg_type;                       /* RNDIS_MSG_INIT_C */
128         __le32  msg_len;
129         __le32  request_id;
130         __le32  status;
131         __le32  major_version;                  // of rndis (1.0)
132         __le32  minor_version;
133         __le32  device_flags;
134         __le32  medium;                         // zero == 802.3
135         __le32  max_packets_per_message;
136         __le32  max_transfer_size;
137         __le32  packet_alignment;               // max 7; (1<<n) bytes
138         __le32  af_list_offset;                 // zero
139         __le32  af_list_size;                   // zero
140 } __attribute__ ((packed));
141
142 struct rndis_halt {             /* OUT (no reply) */
143         // header and:
144         __le32  msg_type;                       /* RNDIS_MSG_HALT */
145         __le32  msg_len;
146         __le32  request_id;
147 } __attribute__ ((packed));
148
149 struct rndis_query {            /* OUT */
150         // header and:
151         __le32  msg_type;                       /* RNDIS_MSG_QUERY */
152         __le32  msg_len;
153         __le32  request_id;
154         __le32  oid;
155         __le32  len;
156         __le32  offset;
157 /*?*/   __le32  handle;                         // zero
158 } __attribute__ ((packed));
159
160 struct rndis_query_c {          /* IN */
161         // header and:
162         __le32  msg_type;                       /* RNDIS_MSG_QUERY_C */
163         __le32  msg_len;
164         __le32  request_id;
165         __le32  status;
166         __le32  len;
167         __le32  offset;
168 } __attribute__ ((packed));
169
170 struct rndis_set {              /* OUT */
171         // header and:
172         __le32  msg_type;                       /* RNDIS_MSG_SET */
173         __le32  msg_len;
174         __le32  request_id;
175         __le32  oid;
176         __le32  len;
177         __le32  offset;
178 /*?*/   __le32  handle;                         // zero
179 } __attribute__ ((packed));
180
181 struct rndis_set_c {            /* IN */
182         // header and:
183         __le32  msg_type;                       /* RNDIS_MSG_SET_C */
184         __le32  msg_len;
185         __le32  request_id;
186         __le32  status;
187 } __attribute__ ((packed));
188
189 struct rndis_reset {            /* IN */
190         // header and:
191         __le32  msg_type;                       /* RNDIS_MSG_RESET */
192         __le32  msg_len;
193         __le32  reserved;
194 } __attribute__ ((packed));
195
196 struct rndis_reset_c {          /* OUT */
197         // header and:
198         __le32  msg_type;                       /* RNDIS_MSG_RESET_C */
199         __le32  msg_len;
200         __le32  status;
201         __le32  addressing_lost;
202 } __attribute__ ((packed));
203
204 struct rndis_indicate {         /* IN (unrequested) */
205         // header and:
206         __le32  msg_type;                       /* RNDIS_MSG_INDICATE */
207         __le32  msg_len;
208         __le32  status;
209         __le32  length;
210         __le32  offset;
211 /**/    __le32  diag_status;
212         __le32  error_offset;
213 /**/    __le32  message;
214 } __attribute__ ((packed));
215
216 struct rndis_keepalive {        /* OUT (optionally IN) */
217         // header and:
218         __le32  msg_type;                       /* RNDIS_MSG_KEEPALIVE */
219         __le32  msg_len;
220         __le32  request_id;
221 } __attribute__ ((packed));
222
223 struct rndis_keepalive_c {      /* IN (optionally OUT) */
224         // header and:
225         __le32  msg_type;                       /* RNDIS_MSG_KEEPALIVE_C */
226         __le32  msg_len;
227         __le32  request_id;
228         __le32  status;
229 } __attribute__ ((packed));
230
231 /* NOTE:  about 30 OIDs are "mandatory" for peripherals to support ... and
232  * there are gobs more that may optionally be supported.  We'll avoid as much
233  * of that mess as possible.
234  */
235 #define OID_802_3_PERMANENT_ADDRESS     ccpu2(0x01010101)
236 #define OID_GEN_CURRENT_PACKET_FILTER   ccpu2(0x0001010e)
237
238 /*
239  * RNDIS notifications from device: command completion; "reverse"
240  * keepalives; etc
241  */
242 static void rndis_status(struct usbnet *dev, struct urb *urb)
243 {
244         devdbg(dev, "rndis status urb, len %d stat %d",
245                 urb->actual_length, urb->status);
246         // FIXME for keepalives, respond immediately (asynchronously)
247         // if not an RNDIS status, do like cdc_status(dev,urb) does
248 }
249
250 /*
251  * RPC done RNDIS-style.  Caller guarantees:
252  * - message is properly byteswapped
253  * - there's no other request pending
254  * - buf can hold up to 1KB response (required by RNDIS spec)
255  * On return, the first few entries are already byteswapped.
256  *
257  * Call context is likely probe(), before interface name is known,
258  * which is why we won't try to use it in the diagnostics.
259  */
260 static int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf)
261 {
262         struct cdc_state        *info = (void *) &dev->data;
263         int                     retval;
264         unsigned                count;
265         __le32                  rsp;
266         u32                     xid = 0, msg_len, request_id;
267
268         /* REVISIT when this gets called from contexts other than probe() or
269          * disconnect(): either serialize, or dispatch responses on xid
270          */
271
272         /* Issue the request; don't bother byteswapping our xid */
273         if (likely(buf->msg_type != RNDIS_MSG_HALT
274                         && buf->msg_type != RNDIS_MSG_RESET)) {
275                 xid = dev->xid++;
276                 if (!xid)
277                         xid = dev->xid++;
278                 buf->request_id = (__force __le32) xid;
279         }
280         retval = usb_control_msg(dev->udev,
281                 usb_sndctrlpipe(dev->udev, 0),
282                 USB_CDC_SEND_ENCAPSULATED_COMMAND,
283                 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
284                 0, info->u->bMasterInterface0,
285                 buf, le32_to_cpu(buf->msg_len),
286                 RNDIS_CONTROL_TIMEOUT_MS);
287         if (unlikely(retval < 0 || xid == 0))
288                 return retval;
289
290         // FIXME Seems like some devices discard responses when
291         // we time out and cancel our "get response" requests...
292         // so, this is fragile.  Probably need to poll for status.
293
294         /* ignore status endpoint, just poll the control channel;
295          * the request probably completed immediately
296          */
297         rsp = buf->msg_type | RNDIS_MSG_COMPLETION;
298         for (count = 0; count < 10; count++) {
299                 memset(buf, 0, 1024);
300                 retval = usb_control_msg(dev->udev,
301                         usb_rcvctrlpipe(dev->udev, 0),
302                         USB_CDC_GET_ENCAPSULATED_RESPONSE,
303                         USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
304                         0, info->u->bMasterInterface0,
305                         buf, 1024,
306                         RNDIS_CONTROL_TIMEOUT_MS);
307                 if (likely(retval >= 8)) {
308                         msg_len = le32_to_cpu(buf->msg_len);
309                         request_id = (__force u32) buf->request_id;
310                         if (likely(buf->msg_type == rsp)) {
311                                 if (likely(request_id == xid)) {
312                                         if (unlikely(rsp == RNDIS_MSG_RESET_C))
313                                                 return 0;
314                                         if (likely(RNDIS_STATUS_SUCCESS
315                                                         == buf->status))
316                                                 return 0;
317                                         dev_dbg(&info->control->dev,
318                                                 "rndis reply status %08x\n",
319                                                 le32_to_cpu(buf->status));
320                                         return -EL3RST;
321                                 }
322                                 dev_dbg(&info->control->dev,
323                                         "rndis reply id %d expected %d\n",
324                                         request_id, xid);
325                                 /* then likely retry */
326                         } else switch (buf->msg_type) {
327                         case RNDIS_MSG_INDICATE: {      /* fault */
328                                 // struct rndis_indicate *msg = (void *)buf;
329                                 dev_info(&info->control->dev,
330                                          "rndis fault indication\n");
331                                 }
332                                 break;
333                         case RNDIS_MSG_KEEPALIVE: {     /* ping */
334                                 struct rndis_keepalive_c *msg = (void *)buf;
335
336                                 msg->msg_type = RNDIS_MSG_KEEPALIVE_C;
337                                 msg->msg_len = ccpu2(sizeof *msg);
338                                 msg->status = RNDIS_STATUS_SUCCESS;
339                                 retval = usb_control_msg(dev->udev,
340                                         usb_sndctrlpipe(dev->udev, 0),
341                                         USB_CDC_SEND_ENCAPSULATED_COMMAND,
342                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE,
343                                         0, info->u->bMasterInterface0,
344                                         msg, sizeof *msg,
345                                         RNDIS_CONTROL_TIMEOUT_MS);
346                                 if (unlikely(retval < 0))
347                                         dev_dbg(&info->control->dev,
348                                                 "rndis keepalive err %d\n",
349                                                 retval);
350                                 }
351                                 break;
352                         default:
353                                 dev_dbg(&info->control->dev,
354                                         "unexpected rndis msg %08x len %d\n",
355                                         le32_to_cpu(buf->msg_type), msg_len);
356                         }
357                 } else {
358                         /* device probably issued a protocol stall; ignore */
359                         dev_dbg(&info->control->dev,
360                                 "rndis response error, code %d\n", retval);
361                 }
362                 msleep(2);
363         }
364         dev_dbg(&info->control->dev, "rndis response timeout\n");
365         return -ETIMEDOUT;
366 }
367
368 static int rndis_bind(struct usbnet *dev, struct usb_interface *intf)
369 {
370         int                     retval;
371         struct net_device       *net = dev->net;
372         union {
373                 void                    *buf;
374                 struct rndis_msg_hdr    *header;
375                 struct rndis_init       *init;
376                 struct rndis_init_c     *init_c;
377                 struct rndis_query      *get;
378                 struct rndis_query_c    *get_c;
379                 struct rndis_set        *set;
380                 struct rndis_set_c      *set_c;
381         } u;
382         u32                     tmp;
383
384         /* we can't rely on i/o from stack working, or stack allocation */
385         u.buf = kmalloc(1024, GFP_KERNEL);
386         if (!u.buf)
387                 return -ENOMEM;
388         retval = usbnet_generic_cdc_bind(dev, intf);
389         if (retval < 0)
390                 goto done;
391
392         net->hard_header_len += sizeof (struct rndis_data_hdr);
393
394         /* initialize; max transfer is 16KB at full speed */
395         u.init->msg_type = RNDIS_MSG_INIT;
396         u.init->msg_len = ccpu2(sizeof *u.init);
397         u.init->major_version = ccpu2(1);
398         u.init->minor_version = ccpu2(0);
399         u.init->max_transfer_size = ccpu2(net->mtu + net->hard_header_len);
400
401         retval = rndis_command(dev, u.header);
402         if (unlikely(retval < 0)) {
403                 /* it might not even be an RNDIS device!! */
404                 dev_err(&intf->dev, "RNDIS init failed, %d\n", retval);
405 fail:
406                 usb_driver_release_interface(driver_of(intf),
407                         ((struct cdc_state *)&(dev->data))->data);
408                 goto done;
409         }
410         dev->hard_mtu = le32_to_cpu(u.init_c->max_transfer_size);
411         /* REVISIT:  peripheral "alignment" request is ignored ... */
412         dev_dbg(&intf->dev, "hard mtu %u, align %d\n", dev->hard_mtu,
413                 1 << le32_to_cpu(u.init_c->packet_alignment));
414
415         /* get designated host ethernet address */
416         memset(u.get, 0, sizeof *u.get);
417         u.get->msg_type = RNDIS_MSG_QUERY;
418         u.get->msg_len = ccpu2(sizeof *u.get);
419         u.get->oid = OID_802_3_PERMANENT_ADDRESS;
420
421         retval = rndis_command(dev, u.header);
422         if (unlikely(retval < 0)) {
423                 dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval);
424                 goto fail;
425         }
426         tmp = le32_to_cpu(u.get_c->offset);
427         if (unlikely((tmp + 8) > (1024 - ETH_ALEN)
428                         || u.get_c->len != ccpu2(ETH_ALEN))) {
429                 dev_err(&intf->dev, "rndis ethaddr off %d len %d ?\n",
430                         tmp, le32_to_cpu(u.get_c->len));
431                 retval = -EDOM;
432                 goto fail;
433         }
434         memcpy(net->dev_addr, tmp + (char *)&u.get_c->request_id, ETH_ALEN);
435
436         /* set a nonzero filter to enable data transfers */
437         memset(u.set, 0, sizeof *u.set);
438         u.set->msg_type = RNDIS_MSG_SET;
439         u.set->msg_len = ccpu2(4 + sizeof *u.set);
440         u.set->oid = OID_GEN_CURRENT_PACKET_FILTER;
441         u.set->len = ccpu2(4);
442         u.set->offset = ccpu2((sizeof *u.set) - 8);
443         *(__le32 *)(u.buf + sizeof *u.set) = ccpu2(DEFAULT_FILTER);
444
445         retval = rndis_command(dev, u.header);
446         if (unlikely(retval < 0)) {
447                 dev_err(&intf->dev, "rndis set packet filter, %d\n", retval);
448                 goto fail;
449         }
450
451         retval = 0;
452 done:
453         kfree(u.buf);
454         return retval;
455 }
456
457 static void rndis_unbind(struct usbnet *dev, struct usb_interface *intf)
458 {
459         struct rndis_halt       *halt;
460
461         /* try to clear any rndis state/activity (no i/o from stack!) */
462         halt = kcalloc(1, sizeof *halt, SLAB_KERNEL);
463         if (halt) {
464                 halt->msg_type = RNDIS_MSG_HALT;
465                 halt->msg_len = ccpu2(sizeof *halt);
466                 (void) rndis_command(dev, (void *)halt);
467                 kfree(halt);
468         }
469
470         return usbnet_cdc_unbind(dev, intf);
471 }
472
473 /*
474  * DATA -- host must not write zlps
475  */
476 static int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
477 {
478         /* peripheral may have batched packets to us... */
479         while (likely(skb->len)) {
480                 struct rndis_data_hdr   *hdr = (void *)skb->data;
481                 struct sk_buff          *skb2;
482                 u32                     msg_len, data_offset, data_len;
483
484                 msg_len = le32_to_cpu(hdr->msg_len);
485                 data_offset = le32_to_cpu(hdr->data_offset);
486                 data_len = le32_to_cpu(hdr->data_len);
487
488                 /* don't choke if we see oob, per-packet data, etc */
489                 if (unlikely(hdr->msg_type != RNDIS_MSG_PACKET
490                                 || skb->len < msg_len
491                                 || (data_offset + data_len + 8) > msg_len)) {
492                         dev->stats.rx_frame_errors++;
493                         devdbg(dev, "bad rndis message %d/%d/%d/%d, len %d",
494                                 le32_to_cpu(hdr->msg_type),
495                                 msg_len, data_offset, data_len, skb->len);
496                         return 0;
497                 }
498                 skb_pull(skb, 8 + data_offset);
499
500                 /* at most one packet left? */
501                 if (likely((data_len - skb->len) <= sizeof *hdr)) {
502                         skb_trim(skb, data_len);
503                         break;
504                 }
505
506                 /* try to return all the packets in the batch */
507                 skb2 = skb_clone(skb, GFP_ATOMIC);
508                 if (unlikely(!skb2))
509                         break;
510                 skb_pull(skb, msg_len - sizeof *hdr);
511                 skb_trim(skb2, data_len);
512                 usbnet_skb_return(dev, skb2);
513         }
514
515         /* caller will usbnet_skb_return the remaining packet */
516         return 1;
517 }
518
519 static struct sk_buff *
520 rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, unsigned flags)
521 {
522         struct rndis_data_hdr   *hdr;
523         struct sk_buff          *skb2;
524         unsigned                len = skb->len;
525
526         if (likely(!skb_cloned(skb))) {
527                 int     room = skb_headroom(skb);
528
529                 /* enough head room as-is? */
530                 if (unlikely((sizeof *hdr) <= room))
531                         goto fill;
532
533                 /* enough room, but needs to be readjusted? */
534                 room += skb_tailroom(skb);
535                 if (likely((sizeof *hdr) <= room)) {
536                         skb->data = memmove(skb->head + sizeof *hdr,
537                                             skb->data, len);
538                         skb->tail = skb->data + len;
539                         goto fill;
540                 }
541         }
542
543         /* create a new skb, with the correct size (and tailpad) */
544         skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags);
545         dev_kfree_skb_any(skb);
546         if (unlikely(!skb2))
547                 return skb2;
548         skb = skb2;
549
550         /* fill out the RNDIS header.  we won't bother trying to batch
551          * packets; Linux minimizes wasted bandwidth through tx queues.
552          */
553 fill:
554         hdr = (void *) __skb_push(skb, sizeof *hdr);
555         memset(hdr, 0, sizeof *hdr);
556         hdr->msg_type = RNDIS_MSG_PACKET;
557         hdr->msg_len = cpu_to_le32(skb->len);
558         hdr->data_offset = ccpu2(sizeof(*hdr) - 8);
559         hdr->data_len = cpu_to_le32(len);
560
561         /* FIXME make the last packet always be short ... */
562         return skb;
563 }
564
565
566 static const struct driver_info rndis_info = {
567         .description =  "RNDIS device",
568         .flags =        FLAG_ETHER | FLAG_FRAMING_RN,
569         .bind =         rndis_bind,
570         .unbind =       rndis_unbind,
571         .status =       rndis_status,
572         .rx_fixup =     rndis_rx_fixup,
573         .tx_fixup =     rndis_tx_fixup,
574 };
575
576 #undef ccpu2
577
578
579 /*-------------------------------------------------------------------------*/
580
581 static const struct usb_device_id       products [] = {
582 {
583         /* RNDIS is MSFT's un-official variant of CDC ACM */
584         USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
585         .driver_info = (unsigned long) &rndis_info,
586 },
587         { },            // END
588 };
589 MODULE_DEVICE_TABLE(usb, products);
590
591 static struct usb_driver rndis_driver = {
592         .owner =        THIS_MODULE,
593         .name =         "rndis_host",
594         .id_table =     products,
595         .probe =        usbnet_probe,
596         .disconnect =   usbnet_disconnect,
597         .suspend =      usbnet_suspend,
598         .resume =       usbnet_resume,
599 };
600
601 static int __init rndis_init(void)
602 {
603         return usb_register(&rndis_driver);
604 }
605 module_init(rndis_init);
606
607 static void __exit rndis_exit(void)
608 {
609         usb_deregister(&rndis_driver);
610 }
611 module_exit(rndis_exit);
612
613 MODULE_AUTHOR("David Brownell");
614 MODULE_DESCRIPTION("USB Host side RNDIS driver");
615 MODULE_LICENSE("GPL");