rndis_host.c 19 KB

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  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. #include <linux/module.h>
  20. #include <linux/init.h>
  21. #include <linux/netdevice.h>
  22. #include <linux/etherdevice.h>
  23. #include <linux/ethtool.h>
  24. #include <linux/workqueue.h>
  25. #include <linux/slab.h>
  26. #include <linux/mii.h>
  27. #include <linux/usb.h>
  28. #include <linux/usb/cdc.h>
  29. #include <linux/usb/usbnet.h>
  30. #include <linux/usb/rndis_host.h>
  31. /*
  32. * RNDIS is NDIS remoted over USB. It's a MSFT variant of CDC ACM ... of
  33. * course ACM was intended for modems, not Ethernet links! USB's standard
  34. * for Ethernet links is "CDC Ethernet", which is significantly simpler.
  35. *
  36. * NOTE that Microsoft's "RNDIS 1.0" specification is incomplete. Issues
  37. * include:
  38. * - Power management in particular relies on information that's scattered
  39. * through other documentation, and which is incomplete or incorrect even
  40. * there.
  41. * - There are various undocumented protocol requirements, such as the
  42. * need to send unused garbage in control-OUT messages.
  43. * - In some cases, MS-Windows will emit undocumented requests; this
  44. * matters more to peripheral implementations than host ones.
  45. *
  46. * Moreover there's a no-open-specs variant of RNDIS called "ActiveSync".
  47. *
  48. * For these reasons and others, ** USE OF RNDIS IS STRONGLY DISCOURAGED ** in
  49. * favor of such non-proprietary alternatives as CDC Ethernet or the newer (and
  50. * currently rare) "Ethernet Emulation Model" (EEM).
  51. */
  52. /*
  53. * RNDIS notifications from device: command completion; "reverse"
  54. * keepalives; etc
  55. */
  56. void rndis_status(struct usbnet *dev, struct urb *urb)
  57. {
  58. netdev_dbg(dev->net, "rndis status urb, len %d stat %d\n",
  59. urb->actual_length, urb->status);
  60. // FIXME for keepalives, respond immediately (asynchronously)
  61. // if not an RNDIS status, do like cdc_status(dev,urb) does
  62. }
  63. EXPORT_SYMBOL_GPL(rndis_status);
  64. /*
  65. * RNDIS indicate messages.
  66. */
  67. static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg,
  68. int buflen)
  69. {
  70. struct cdc_state *info = (void *)&dev->data;
  71. struct device *udev = &info->control->dev;
  72. if (dev->driver_info->indication) {
  73. dev->driver_info->indication(dev, msg, buflen);
  74. } else {
  75. switch (msg->status) {
  76. case RNDIS_STATUS_MEDIA_CONNECT:
  77. dev_info(udev, "rndis media connect\n");
  78. break;
  79. case RNDIS_STATUS_MEDIA_DISCONNECT:
  80. dev_info(udev, "rndis media disconnect\n");
  81. break;
  82. default:
  83. dev_info(udev, "rndis indication: 0x%08x\n",
  84. le32_to_cpu(msg->status));
  85. }
  86. }
  87. }
  88. /*
  89. * RPC done RNDIS-style. Caller guarantees:
  90. * - message is properly byteswapped
  91. * - there's no other request pending
  92. * - buf can hold up to 1KB response (required by RNDIS spec)
  93. * On return, the first few entries are already byteswapped.
  94. *
  95. * Call context is likely probe(), before interface name is known,
  96. * which is why we won't try to use it in the diagnostics.
  97. */
  98. int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf, int buflen)
  99. {
  100. struct cdc_state *info = (void *) &dev->data;
  101. struct usb_cdc_notification notification;
  102. int master_ifnum;
  103. int retval;
  104. int partial;
  105. unsigned count;
  106. __le32 rsp;
  107. u32 xid = 0, msg_len, request_id;
  108. /* REVISIT when this gets called from contexts other than probe() or
  109. * disconnect(): either serialize, or dispatch responses on xid
  110. */
  111. /* Issue the request; xid is unique, don't bother byteswapping it */
  112. if (likely(buf->msg_type != RNDIS_MSG_HALT &&
  113. buf->msg_type != RNDIS_MSG_RESET)) {
  114. xid = dev->xid++;
  115. if (!xid)
  116. xid = dev->xid++;
  117. buf->request_id = (__force __le32) xid;
  118. }
  119. master_ifnum = info->control->cur_altsetting->desc.bInterfaceNumber;
  120. retval = usb_control_msg(dev->udev,
  121. usb_sndctrlpipe(dev->udev, 0),
  122. USB_CDC_SEND_ENCAPSULATED_COMMAND,
  123. USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  124. 0, master_ifnum,
  125. buf, le32_to_cpu(buf->msg_len),
  126. RNDIS_CONTROL_TIMEOUT_MS);
  127. if (unlikely(retval < 0 || xid == 0))
  128. return retval;
  129. /* Some devices don't respond on the control channel until
  130. * polled on the status channel, so do that first. */
  131. if (dev->driver_info->data & RNDIS_DRIVER_DATA_POLL_STATUS) {
  132. retval = usb_interrupt_msg(
  133. dev->udev,
  134. usb_rcvintpipe(dev->udev,
  135. dev->status->desc.bEndpointAddress),
  136. &notification, sizeof(notification), &partial,
  137. RNDIS_CONTROL_TIMEOUT_MS);
  138. if (unlikely(retval < 0))
  139. return retval;
  140. }
  141. /* Poll the control channel; the request probably completed immediately */
  142. rsp = buf->msg_type | RNDIS_MSG_COMPLETION;
  143. for (count = 0; count < 10; count++) {
  144. memset(buf, 0, CONTROL_BUFFER_SIZE);
  145. retval = usb_control_msg(dev->udev,
  146. usb_rcvctrlpipe(dev->udev, 0),
  147. USB_CDC_GET_ENCAPSULATED_RESPONSE,
  148. USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  149. 0, master_ifnum,
  150. buf, buflen,
  151. RNDIS_CONTROL_TIMEOUT_MS);
  152. if (likely(retval >= 8)) {
  153. msg_len = le32_to_cpu(buf->msg_len);
  154. request_id = (__force u32) buf->request_id;
  155. if (likely(buf->msg_type == rsp)) {
  156. if (likely(request_id == xid)) {
  157. if (unlikely(rsp == RNDIS_MSG_RESET_C))
  158. return 0;
  159. if (likely(RNDIS_STATUS_SUCCESS
  160. == buf->status))
  161. return 0;
  162. dev_dbg(&info->control->dev,
  163. "rndis reply status %08x\n",
  164. le32_to_cpu(buf->status));
  165. return -EL3RST;
  166. }
  167. dev_dbg(&info->control->dev,
  168. "rndis reply id %d expected %d\n",
  169. request_id, xid);
  170. /* then likely retry */
  171. } else switch (buf->msg_type) {
  172. case RNDIS_MSG_INDICATE: /* fault/event */
  173. rndis_msg_indicate(dev, (void *)buf, buflen);
  174. break;
  175. case RNDIS_MSG_KEEPALIVE: { /* ping */
  176. struct rndis_keepalive_c *msg = (void *)buf;
  177. msg->msg_type = RNDIS_MSG_KEEPALIVE_C;
  178. msg->msg_len = cpu_to_le32(sizeof *msg);
  179. msg->status = RNDIS_STATUS_SUCCESS;
  180. retval = usb_control_msg(dev->udev,
  181. usb_sndctrlpipe(dev->udev, 0),
  182. USB_CDC_SEND_ENCAPSULATED_COMMAND,
  183. USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  184. 0, master_ifnum,
  185. msg, sizeof *msg,
  186. RNDIS_CONTROL_TIMEOUT_MS);
  187. if (unlikely(retval < 0))
  188. dev_dbg(&info->control->dev,
  189. "rndis keepalive err %d\n",
  190. retval);
  191. }
  192. break;
  193. default:
  194. dev_dbg(&info->control->dev,
  195. "unexpected rndis msg %08x len %d\n",
  196. le32_to_cpu(buf->msg_type), msg_len);
  197. }
  198. } else {
  199. /* device probably issued a protocol stall; ignore */
  200. dev_dbg(&info->control->dev,
  201. "rndis response error, code %d\n", retval);
  202. }
  203. msleep(20);
  204. }
  205. dev_dbg(&info->control->dev, "rndis response timeout\n");
  206. return -ETIMEDOUT;
  207. }
  208. EXPORT_SYMBOL_GPL(rndis_command);
  209. /*
  210. * rndis_query:
  211. *
  212. * Performs a query for @oid along with 0 or more bytes of payload as
  213. * specified by @in_len. If @reply_len is not set to -1 then the reply
  214. * length is checked against this value, resulting in an error if it
  215. * doesn't match.
  216. *
  217. * NOTE: Adding a payload exactly or greater than the size of the expected
  218. * response payload is an evident requirement MSFT added for ActiveSync.
  219. *
  220. * The only exception is for OIDs that return a variably sized response,
  221. * in which case no payload should be added. This undocumented (and
  222. * nonsensical!) issue was found by sniffing protocol requests from the
  223. * ActiveSync 4.1 Windows driver.
  224. */
  225. static int rndis_query(struct usbnet *dev, struct usb_interface *intf,
  226. void *buf, __le32 oid, u32 in_len,
  227. void **reply, int *reply_len)
  228. {
  229. int retval;
  230. union {
  231. void *buf;
  232. struct rndis_msg_hdr *header;
  233. struct rndis_query *get;
  234. struct rndis_query_c *get_c;
  235. } u;
  236. u32 off, len;
  237. u.buf = buf;
  238. memset(u.get, 0, sizeof *u.get + in_len);
  239. u.get->msg_type = RNDIS_MSG_QUERY;
  240. u.get->msg_len = cpu_to_le32(sizeof *u.get + in_len);
  241. u.get->oid = oid;
  242. u.get->len = cpu_to_le32(in_len);
  243. u.get->offset = cpu_to_le32(20);
  244. retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
  245. if (unlikely(retval < 0)) {
  246. dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) failed, %d\n",
  247. oid, retval);
  248. return retval;
  249. }
  250. off = le32_to_cpu(u.get_c->offset);
  251. len = le32_to_cpu(u.get_c->len);
  252. if (unlikely((8 + off + len) > CONTROL_BUFFER_SIZE))
  253. goto response_error;
  254. if (*reply_len != -1 && len != *reply_len)
  255. goto response_error;
  256. *reply = (unsigned char *) &u.get_c->request_id + off;
  257. *reply_len = len;
  258. return retval;
  259. response_error:
  260. dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) "
  261. "invalid response - off %d len %d\n",
  262. oid, off, len);
  263. return -EDOM;
  264. }
  265. /* same as usbnet_netdev_ops but MTU change not allowed */
  266. static const struct net_device_ops rndis_netdev_ops = {
  267. .ndo_open = usbnet_open,
  268. .ndo_stop = usbnet_stop,
  269. .ndo_start_xmit = usbnet_start_xmit,
  270. .ndo_tx_timeout = usbnet_tx_timeout,
  271. .ndo_set_mac_address = eth_mac_addr,
  272. .ndo_validate_addr = eth_validate_addr,
  273. };
  274. int
  275. generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags)
  276. {
  277. int retval;
  278. struct net_device *net = dev->net;
  279. struct cdc_state *info = (void *) &dev->data;
  280. union {
  281. void *buf;
  282. struct rndis_msg_hdr *header;
  283. struct rndis_init *init;
  284. struct rndis_init_c *init_c;
  285. struct rndis_query *get;
  286. struct rndis_query_c *get_c;
  287. struct rndis_set *set;
  288. struct rndis_set_c *set_c;
  289. struct rndis_halt *halt;
  290. } u;
  291. u32 tmp;
  292. __le32 phym_unspec, *phym;
  293. int reply_len;
  294. unsigned char *bp;
  295. /* we can't rely on i/o from stack working, or stack allocation */
  296. u.buf = kmalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
  297. if (!u.buf)
  298. return -ENOMEM;
  299. retval = usbnet_generic_cdc_bind(dev, intf);
  300. if (retval < 0)
  301. goto fail;
  302. u.init->msg_type = RNDIS_MSG_INIT;
  303. u.init->msg_len = cpu_to_le32(sizeof *u.init);
  304. u.init->major_version = cpu_to_le32(1);
  305. u.init->minor_version = cpu_to_le32(0);
  306. /* max transfer (in spec) is 0x4000 at full speed, but for
  307. * TX we'll stick to one Ethernet packet plus RNDIS framing.
  308. * For RX we handle drivers that zero-pad to end-of-packet.
  309. * Don't let userspace change these settings.
  310. *
  311. * NOTE: there still seems to be wierdness here, as if we need
  312. * to do some more things to make sure WinCE targets accept this.
  313. * They default to jumbograms of 8KB or 16KB, which is absurd
  314. * for such low data rates and which is also more than Linux
  315. * can usually expect to allocate for SKB data...
  316. */
  317. net->hard_header_len += sizeof (struct rndis_data_hdr);
  318. dev->hard_mtu = net->mtu + net->hard_header_len;
  319. dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1);
  320. if (dev->maxpacket == 0) {
  321. netif_dbg(dev, probe, dev->net,
  322. "dev->maxpacket can't be 0\n");
  323. retval = -EINVAL;
  324. goto fail_and_release;
  325. }
  326. dev->rx_urb_size = dev->hard_mtu + (dev->maxpacket + 1);
  327. dev->rx_urb_size &= ~(dev->maxpacket - 1);
  328. u.init->max_transfer_size = cpu_to_le32(dev->rx_urb_size);
  329. net->netdev_ops = &rndis_netdev_ops;
  330. retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
  331. if (unlikely(retval < 0)) {
  332. /* it might not even be an RNDIS device!! */
  333. dev_err(&intf->dev, "RNDIS init failed, %d\n", retval);
  334. goto fail_and_release;
  335. }
  336. tmp = le32_to_cpu(u.init_c->max_transfer_size);
  337. if (tmp < dev->hard_mtu) {
  338. if (tmp <= net->hard_header_len) {
  339. dev_err(&intf->dev,
  340. "dev can't take %u byte packets (max %u)\n",
  341. dev->hard_mtu, tmp);
  342. retval = -EINVAL;
  343. goto halt_fail_and_release;
  344. }
  345. dev_warn(&intf->dev,
  346. "dev can't take %u byte packets (max %u), "
  347. "adjusting MTU to %u\n",
  348. dev->hard_mtu, tmp, tmp - net->hard_header_len);
  349. dev->hard_mtu = tmp;
  350. net->mtu = dev->hard_mtu - net->hard_header_len;
  351. }
  352. /* REVISIT: peripheral "alignment" request is ignored ... */
  353. dev_dbg(&intf->dev,
  354. "hard mtu %u (%u from dev), rx buflen %Zu, align %d\n",
  355. dev->hard_mtu, tmp, dev->rx_urb_size,
  356. 1 << le32_to_cpu(u.init_c->packet_alignment));
  357. /* module has some device initialization code needs to be done right
  358. * after RNDIS_INIT */
  359. if (dev->driver_info->early_init &&
  360. dev->driver_info->early_init(dev) != 0)
  361. goto halt_fail_and_release;
  362. /* Check physical medium */
  363. phym = NULL;
  364. reply_len = sizeof *phym;
  365. retval = rndis_query(dev, intf, u.buf, OID_GEN_PHYSICAL_MEDIUM,
  366. 0, (void **) &phym, &reply_len);
  367. if (retval != 0 || !phym) {
  368. /* OID is optional so don't fail here. */
  369. phym_unspec = RNDIS_PHYSICAL_MEDIUM_UNSPECIFIED;
  370. phym = &phym_unspec;
  371. }
  372. if ((flags & FLAG_RNDIS_PHYM_WIRELESS) &&
  373. *phym != RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
  374. netif_dbg(dev, probe, dev->net,
  375. "driver requires wireless physical medium, but device is not\n");
  376. retval = -ENODEV;
  377. goto halt_fail_and_release;
  378. }
  379. if ((flags & FLAG_RNDIS_PHYM_NOT_WIRELESS) &&
  380. *phym == RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
  381. netif_dbg(dev, probe, dev->net,
  382. "driver requires non-wireless physical medium, but device is wireless.\n");
  383. retval = -ENODEV;
  384. goto halt_fail_and_release;
  385. }
  386. /* Get designated host ethernet address */
  387. reply_len = ETH_ALEN;
  388. retval = rndis_query(dev, intf, u.buf, OID_802_3_PERMANENT_ADDRESS,
  389. 48, (void **) &bp, &reply_len);
  390. if (unlikely(retval< 0)) {
  391. dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval);
  392. goto halt_fail_and_release;
  393. }
  394. memcpy(net->dev_addr, bp, ETH_ALEN);
  395. memcpy(net->perm_addr, bp, ETH_ALEN);
  396. /* set a nonzero filter to enable data transfers */
  397. memset(u.set, 0, sizeof *u.set);
  398. u.set->msg_type = RNDIS_MSG_SET;
  399. u.set->msg_len = cpu_to_le32(4 + sizeof *u.set);
  400. u.set->oid = OID_GEN_CURRENT_PACKET_FILTER;
  401. u.set->len = cpu_to_le32(4);
  402. u.set->offset = cpu_to_le32((sizeof *u.set) - 8);
  403. *(__le32 *)(u.buf + sizeof *u.set) = RNDIS_DEFAULT_FILTER;
  404. retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
  405. if (unlikely(retval < 0)) {
  406. dev_err(&intf->dev, "rndis set packet filter, %d\n", retval);
  407. goto halt_fail_and_release;
  408. }
  409. retval = 0;
  410. kfree(u.buf);
  411. return retval;
  412. halt_fail_and_release:
  413. memset(u.halt, 0, sizeof *u.halt);
  414. u.halt->msg_type = RNDIS_MSG_HALT;
  415. u.halt->msg_len = cpu_to_le32(sizeof *u.halt);
  416. (void) rndis_command(dev, (void *)u.halt, CONTROL_BUFFER_SIZE);
  417. fail_and_release:
  418. usb_set_intfdata(info->data, NULL);
  419. usb_driver_release_interface(driver_of(intf), info->data);
  420. info->data = NULL;
  421. fail:
  422. kfree(u.buf);
  423. return retval;
  424. }
  425. EXPORT_SYMBOL_GPL(generic_rndis_bind);
  426. static int rndis_bind(struct usbnet *dev, struct usb_interface *intf)
  427. {
  428. return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS);
  429. }
  430. void rndis_unbind(struct usbnet *dev, struct usb_interface *intf)
  431. {
  432. struct rndis_halt *halt;
  433. /* try to clear any rndis state/activity (no i/o from stack!) */
  434. halt = kzalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
  435. if (halt) {
  436. halt->msg_type = RNDIS_MSG_HALT;
  437. halt->msg_len = cpu_to_le32(sizeof *halt);
  438. (void) rndis_command(dev, (void *)halt, CONTROL_BUFFER_SIZE);
  439. kfree(halt);
  440. }
  441. usbnet_cdc_unbind(dev, intf);
  442. }
  443. EXPORT_SYMBOL_GPL(rndis_unbind);
  444. /*
  445. * DATA -- host must not write zlps
  446. */
  447. int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
  448. {
  449. /* peripheral may have batched packets to us... */
  450. while (likely(skb->len)) {
  451. struct rndis_data_hdr *hdr = (void *)skb->data;
  452. struct sk_buff *skb2;
  453. u32 msg_len, data_offset, data_len;
  454. msg_len = le32_to_cpu(hdr->msg_len);
  455. data_offset = le32_to_cpu(hdr->data_offset);
  456. data_len = le32_to_cpu(hdr->data_len);
  457. /* don't choke if we see oob, per-packet data, etc */
  458. if (unlikely(hdr->msg_type != RNDIS_MSG_PACKET ||
  459. skb->len < msg_len ||
  460. (data_offset + data_len + 8) > msg_len)) {
  461. dev->net->stats.rx_frame_errors++;
  462. netdev_dbg(dev->net, "bad rndis message %d/%d/%d/%d, len %d\n",
  463. le32_to_cpu(hdr->msg_type),
  464. msg_len, data_offset, data_len, skb->len);
  465. return 0;
  466. }
  467. skb_pull(skb, 8 + data_offset);
  468. /* at most one packet left? */
  469. if (likely((data_len - skb->len) <= sizeof *hdr)) {
  470. skb_trim(skb, data_len);
  471. break;
  472. }
  473. /* try to return all the packets in the batch */
  474. skb2 = skb_clone(skb, GFP_ATOMIC);
  475. if (unlikely(!skb2))
  476. break;
  477. skb_pull(skb, msg_len - sizeof *hdr);
  478. skb_trim(skb2, data_len);
  479. usbnet_skb_return(dev, skb2);
  480. }
  481. /* caller will usbnet_skb_return the remaining packet */
  482. return 1;
  483. }
  484. EXPORT_SYMBOL_GPL(rndis_rx_fixup);
  485. struct sk_buff *
  486. rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
  487. {
  488. struct rndis_data_hdr *hdr;
  489. struct sk_buff *skb2;
  490. unsigned len = skb->len;
  491. if (likely(!skb_cloned(skb))) {
  492. int room = skb_headroom(skb);
  493. /* enough head room as-is? */
  494. if (unlikely((sizeof *hdr) <= room))
  495. goto fill;
  496. /* enough room, but needs to be readjusted? */
  497. room += skb_tailroom(skb);
  498. if (likely((sizeof *hdr) <= room)) {
  499. skb->data = memmove(skb->head + sizeof *hdr,
  500. skb->data, len);
  501. skb_set_tail_pointer(skb, len);
  502. goto fill;
  503. }
  504. }
  505. /* create a new skb, with the correct size (and tailpad) */
  506. skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags);
  507. dev_kfree_skb_any(skb);
  508. if (unlikely(!skb2))
  509. return skb2;
  510. skb = skb2;
  511. /* fill out the RNDIS header. we won't bother trying to batch
  512. * packets; Linux minimizes wasted bandwidth through tx queues.
  513. */
  514. fill:
  515. hdr = (void *) __skb_push(skb, sizeof *hdr);
  516. memset(hdr, 0, sizeof *hdr);
  517. hdr->msg_type = RNDIS_MSG_PACKET;
  518. hdr->msg_len = cpu_to_le32(skb->len);
  519. hdr->data_offset = cpu_to_le32(sizeof(*hdr) - 8);
  520. hdr->data_len = cpu_to_le32(len);
  521. /* FIXME make the last packet always be short ... */
  522. return skb;
  523. }
  524. EXPORT_SYMBOL_GPL(rndis_tx_fixup);
  525. static const struct driver_info rndis_info = {
  526. .description = "RNDIS device",
  527. .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
  528. .bind = rndis_bind,
  529. .unbind = rndis_unbind,
  530. .status = rndis_status,
  531. .rx_fixup = rndis_rx_fixup,
  532. .tx_fixup = rndis_tx_fixup,
  533. };
  534. static const struct driver_info rndis_poll_status_info = {
  535. .description = "RNDIS device (poll status before control)",
  536. .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
  537. .data = RNDIS_DRIVER_DATA_POLL_STATUS,
  538. .bind = rndis_bind,
  539. .unbind = rndis_unbind,
  540. .status = rndis_status,
  541. .rx_fixup = rndis_rx_fixup,
  542. .tx_fixup = rndis_tx_fixup,
  543. };
  544. /*-------------------------------------------------------------------------*/
  545. static const struct usb_device_id products [] = {
  546. {
  547. /* 2Wire HomePortal 1000SW */
  548. USB_DEVICE_AND_INTERFACE_INFO(0x1630, 0x0042,
  549. USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
  550. .driver_info = (unsigned long) &rndis_poll_status_info,
  551. }, {
  552. /* RNDIS is MSFT's un-official variant of CDC ACM */
  553. USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
  554. .driver_info = (unsigned long) &rndis_info,
  555. }, {
  556. /* "ActiveSync" is an undocumented variant of RNDIS, used in WM5 */
  557. USB_INTERFACE_INFO(USB_CLASS_MISC, 1, 1),
  558. .driver_info = (unsigned long) &rndis_poll_status_info,
  559. }, {
  560. /* RNDIS for tethering */
  561. USB_INTERFACE_INFO(USB_CLASS_WIRELESS_CONTROLLER, 1, 3),
  562. .driver_info = (unsigned long) &rndis_info,
  563. },
  564. { }, // END
  565. };
  566. MODULE_DEVICE_TABLE(usb, products);
  567. static struct usb_driver rndis_driver = {
  568. .name = "rndis_host",
  569. .id_table = products,
  570. .probe = usbnet_probe,
  571. .disconnect = usbnet_disconnect,
  572. .suspend = usbnet_suspend,
  573. .resume = usbnet_resume,
  574. };
  575. static int __init rndis_init(void)
  576. {
  577. return usb_register(&rndis_driver);
  578. }
  579. module_init(rndis_init);
  580. static void __exit rndis_exit(void)
  581. {
  582. usb_deregister(&rndis_driver);
  583. }
  584. module_exit(rndis_exit);
  585. MODULE_AUTHOR("David Brownell");
  586. MODULE_DESCRIPTION("USB Host side RNDIS driver");
  587. MODULE_LICENSE("GPL");