linux/drivers/net/usb/rndis_host.c
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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
  33/*
  34 * RNDIS is NDIS remoted over USB.  It's a MSFT variant of CDC ACM ... of
  35 * course ACM was intended for modems, not Ethernet links!  USB's standard
  36 * for Ethernet links is "CDC Ethernet", which is significantly simpler.
  37 *
  38 * NOTE that Microsoft's "RNDIS 1.0" specification is incomplete.  Issues
  39 * include:
  40 *    - Power management in particular relies on information that's scattered
  41 *      through other documentation, and which is incomplete or incorrect even
  42 *      there.
  43 *    - There are various undocumented protocol requirements, such as the
  44 *      need to send unused garbage in control-OUT messages.
  45 *    - In some cases, MS-Windows will emit undocumented requests; this
  46 *      matters more to peripheral implementations than host ones.
  47 *
  48 * Moreover there's a no-open-specs variant of RNDIS called "ActiveSync".
  49 *
  50 * For these reasons and others, ** USE OF RNDIS IS STRONGLY DISCOURAGED ** in
  51 * favor of such non-proprietary alternatives as CDC Ethernet or the newer (and
  52 * currently rare) "Ethernet Emulation Model" (EEM).
  53 */
  54
  55/*
  56 * RNDIS notifications from device: command completion; "reverse"
  57 * keepalives; etc
  58 */
  59void rndis_status(struct usbnet *dev, struct urb *urb)
  60{
  61        netdev_dbg(dev->net, "rndis status urb, len %d stat %d\n",
  62                   urb->actual_length, urb->status);
  63        // FIXME for keepalives, respond immediately (asynchronously)
  64        // if not an RNDIS status, do like cdc_status(dev,urb) does
  65}
  66EXPORT_SYMBOL_GPL(rndis_status);
  67
  68/*
  69 * RNDIS indicate messages.
  70 */
  71static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg,
  72                                int buflen)
  73{
  74        struct cdc_state *info = (void *)&dev->data;
  75        struct device *udev = &info->control->dev;
  76
  77        if (dev->driver_info->indication) {
  78                dev->driver_info->indication(dev, msg, buflen);
  79        } else {
  80                switch (msg->status) {
  81                case RNDIS_STATUS_MEDIA_CONNECT:
  82                        dev_info(udev, "rndis media connect\n");
  83                        break;
  84                case RNDIS_STATUS_MEDIA_DISCONNECT:
  85                        dev_info(udev, "rndis media disconnect\n");
  86                        break;
  87                default:
  88                        dev_info(udev, "rndis indication: 0x%08x\n",
  89                                        le32_to_cpu(msg->status));
  90                }
  91        }
  92}
  93
  94/*
  95 * RPC done RNDIS-style.  Caller guarantees:
  96 * - message is properly byteswapped
  97 * - there's no other request pending
  98 * - buf can hold up to 1KB response (required by RNDIS spec)
  99 * On return, the first few entries are already byteswapped.
 100 *
 101 * Call context is likely probe(), before interface name is known,
 102 * which is why we won't try to use it in the diagnostics.
 103 */
 104int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf, int buflen)
 105{
 106        struct cdc_state        *info = (void *) &dev->data;
 107        struct usb_cdc_notification notification;
 108        int                     master_ifnum;
 109        int                     retval;
 110        int                     partial;
 111        unsigned                count;
 112        __le32                  rsp;
 113        u32                     xid = 0, msg_len, request_id;
 114
 115        /* REVISIT when this gets called from contexts other than probe() or
 116         * disconnect(): either serialize, or dispatch responses on xid
 117         */
 118
 119        /* Issue the request; xid is unique, don't bother byteswapping it */
 120        if (likely(buf->msg_type != RNDIS_MSG_HALT &&
 121                   buf->msg_type != RNDIS_MSG_RESET)) {
 122                xid = dev->xid++;
 123                if (!xid)
 124                        xid = dev->xid++;
 125                buf->request_id = (__force __le32) xid;
 126        }
 127        master_ifnum = info->control->cur_altsetting->desc.bInterfaceNumber;
 128        retval = usb_control_msg(dev->udev,
 129                usb_sndctrlpipe(dev->udev, 0),
 130                USB_CDC_SEND_ENCAPSULATED_COMMAND,
 131                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 132                0, master_ifnum,
 133                buf, le32_to_cpu(buf->msg_len),
 134                RNDIS_CONTROL_TIMEOUT_MS);
 135        if (unlikely(retval < 0 || xid == 0))
 136                return retval;
 137
 138        /* Some devices don't respond on the control channel until
 139         * polled on the status channel, so do that first. */
 140        if (dev->driver_info->data & RNDIS_DRIVER_DATA_POLL_STATUS) {
 141                retval = usb_interrupt_msg(
 142                        dev->udev,
 143                        usb_rcvintpipe(dev->udev,
 144                                       dev->status->desc.bEndpointAddress),
 145                        &notification, sizeof(notification), &partial,
 146                        RNDIS_CONTROL_TIMEOUT_MS);
 147                if (unlikely(retval < 0))
 148                        return retval;
 149        }
 150
 151        /* Poll the control channel; the request probably completed immediately */
 152        rsp = buf->msg_type | RNDIS_MSG_COMPLETION;
 153        for (count = 0; count < 10; count++) {
 154                memset(buf, 0, CONTROL_BUFFER_SIZE);
 155                retval = usb_control_msg(dev->udev,
 156                        usb_rcvctrlpipe(dev->udev, 0),
 157                        USB_CDC_GET_ENCAPSULATED_RESPONSE,
 158                        USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 159                        0, master_ifnum,
 160                        buf, buflen,
 161                        RNDIS_CONTROL_TIMEOUT_MS);
 162                if (likely(retval >= 8)) {
 163                        msg_len = le32_to_cpu(buf->msg_len);
 164                        request_id = (__force u32) buf->request_id;
 165                        if (likely(buf->msg_type == rsp)) {
 166                                if (likely(request_id == xid)) {
 167                                        if (unlikely(rsp == RNDIS_MSG_RESET_C))
 168                                                return 0;
 169                                        if (likely(RNDIS_STATUS_SUCCESS
 170                                                        == buf->status))
 171                                                return 0;
 172                                        dev_dbg(&info->control->dev,
 173                                                "rndis reply status %08x\n",
 174                                                le32_to_cpu(buf->status));
 175                                        return -EL3RST;
 176                                }
 177                                dev_dbg(&info->control->dev,
 178                                        "rndis reply id %d expected %d\n",
 179                                        request_id, xid);
 180                                /* then likely retry */
 181                        } else switch (buf->msg_type) {
 182                        case RNDIS_MSG_INDICATE:        /* fault/event */
 183                                rndis_msg_indicate(dev, (void *)buf, buflen);
 184
 185                                break;
 186                        case RNDIS_MSG_KEEPALIVE: {     /* ping */
 187                                struct rndis_keepalive_c *msg = (void *)buf;
 188
 189                                msg->msg_type = RNDIS_MSG_KEEPALIVE_C;
 190                                msg->msg_len = cpu_to_le32(sizeof *msg);
 191                                msg->status = RNDIS_STATUS_SUCCESS;
 192                                retval = usb_control_msg(dev->udev,
 193                                        usb_sndctrlpipe(dev->udev, 0),
 194                                        USB_CDC_SEND_ENCAPSULATED_COMMAND,
 195                                        USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 196                                        0, master_ifnum,
 197                                        msg, sizeof *msg,
 198                                        RNDIS_CONTROL_TIMEOUT_MS);
 199                                if (unlikely(retval < 0))
 200                                        dev_dbg(&info->control->dev,
 201                                                "rndis keepalive err %d\n",
 202                                                retval);
 203                                }
 204                                break;
 205                        default:
 206                                dev_dbg(&info->control->dev,
 207                                        "unexpected rndis msg %08x len %d\n",
 208                                        le32_to_cpu(buf->msg_type), msg_len);
 209                        }
 210                } else {
 211                        /* device probably issued a protocol stall; ignore */
 212                        dev_dbg(&info->control->dev,
 213                                "rndis response error, code %d\n", retval);
 214                }
 215                msleep(20);
 216        }
 217        dev_dbg(&info->control->dev, "rndis response timeout\n");
 218        return -ETIMEDOUT;
 219}
 220EXPORT_SYMBOL_GPL(rndis_command);
 221
 222/*
 223 * rndis_query:
 224 *
 225 * Performs a query for @oid along with 0 or more bytes of payload as
 226 * specified by @in_len. If @reply_len is not set to -1 then the reply
 227 * length is checked against this value, resulting in an error if it
 228 * doesn't match.
 229 *
 230 * NOTE: Adding a payload exactly or greater than the size of the expected
 231 * response payload is an evident requirement MSFT added for ActiveSync.
 232 *
 233 * The only exception is for OIDs that return a variably sized response,
 234 * in which case no payload should be added.  This undocumented (and
 235 * nonsensical!) issue was found by sniffing protocol requests from the
 236 * ActiveSync 4.1 Windows driver.
 237 */
 238static int rndis_query(struct usbnet *dev, struct usb_interface *intf,
 239                void *buf, __le32 oid, u32 in_len,
 240                void **reply, int *reply_len)
 241{
 242        int retval;
 243        union {
 244                void                    *buf;
 245                struct rndis_msg_hdr    *header;
 246                struct rndis_query      *get;
 247                struct rndis_query_c    *get_c;
 248        } u;
 249        u32 off, len;
 250
 251        u.buf = buf;
 252
 253        memset(u.get, 0, sizeof *u.get + in_len);
 254        u.get->msg_type = RNDIS_MSG_QUERY;
 255        u.get->msg_len = cpu_to_le32(sizeof *u.get + in_len);
 256        u.get->oid = oid;
 257        u.get->len = cpu_to_le32(in_len);
 258        u.get->offset = cpu_to_le32(20);
 259
 260        retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
 261        if (unlikely(retval < 0)) {
 262                dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) failed, %d\n",
 263                                oid, retval);
 264                return retval;
 265        }
 266
 267        off = le32_to_cpu(u.get_c->offset);
 268        len = le32_to_cpu(u.get_c->len);
 269        if (unlikely((8 + off + len) > CONTROL_BUFFER_SIZE))
 270                goto response_error;
 271
 272        if (*reply_len != -1 && len != *reply_len)
 273                goto response_error;
 274
 275        *reply = (unsigned char *) &u.get_c->request_id + off;
 276        *reply_len = len;
 277
 278        return retval;
 279
 280response_error:
 281        dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) "
 282                        "invalid response - off %d len %d\n",
 283                oid, off, len);
 284        return -EDOM;
 285}
 286
 287/* same as usbnet_netdev_ops but MTU change not allowed */
 288static const struct net_device_ops rndis_netdev_ops = {
 289        .ndo_open               = usbnet_open,
 290        .ndo_stop               = usbnet_stop,
 291        .ndo_start_xmit         = usbnet_start_xmit,
 292        .ndo_tx_timeout         = usbnet_tx_timeout,
 293        .ndo_set_mac_address    = eth_mac_addr,
 294        .ndo_validate_addr      = eth_validate_addr,
 295};
 296
 297int
 298generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags)
 299{
 300        int                     retval;
 301        struct net_device       *net = dev->net;
 302        struct cdc_state        *info = (void *) &dev->data;
 303        union {
 304                void                    *buf;
 305                struct rndis_msg_hdr    *header;
 306                struct rndis_init       *init;
 307                struct rndis_init_c     *init_c;
 308                struct rndis_query      *get;
 309                struct rndis_query_c    *get_c;
 310                struct rndis_set        *set;
 311                struct rndis_set_c      *set_c;
 312                struct rndis_halt       *halt;
 313        } u;
 314        u32                     tmp;
 315        __le32                  phym_unspec, *phym;
 316        int                     reply_len;
 317        unsigned char           *bp;
 318
 319        /* we can't rely on i/o from stack working, or stack allocation */
 320        u.buf = kmalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
 321        if (!u.buf)
 322                return -ENOMEM;
 323        retval = usbnet_generic_cdc_bind(dev, intf);
 324        if (retval < 0)
 325                goto fail;
 326
 327        u.init->msg_type = RNDIS_MSG_INIT;
 328        u.init->msg_len = cpu_to_le32(sizeof *u.init);
 329        u.init->major_version = cpu_to_le32(1);
 330        u.init->minor_version = cpu_to_le32(0);
 331
 332        /* max transfer (in spec) is 0x4000 at full speed, but for
 333         * TX we'll stick to one Ethernet packet plus RNDIS framing.
 334         * For RX we handle drivers that zero-pad to end-of-packet.
 335         * Don't let userspace change these settings.
 336         *
 337         * NOTE: there still seems to be wierdness here, as if we need
 338         * to do some more things to make sure WinCE targets accept this.
 339         * They default to jumbograms of 8KB or 16KB, which is absurd
 340         * for such low data rates and which is also more than Linux
 341         * can usually expect to allocate for SKB data...
 342         */
 343        net->hard_header_len += sizeof (struct rndis_data_hdr);
 344        dev->hard_mtu = net->mtu + net->hard_header_len;
 345
 346        dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1);
 347        if (dev->maxpacket == 0) {
 348                netif_dbg(dev, probe, dev->net,
 349                          "dev->maxpacket can't be 0\n");
 350                retval = -EINVAL;
 351                goto fail_and_release;
 352        }
 353
 354        dev->rx_urb_size = dev->hard_mtu + (dev->maxpacket + 1);
 355        dev->rx_urb_size &= ~(dev->maxpacket - 1);
 356        u.init->max_transfer_size = cpu_to_le32(dev->rx_urb_size);
 357
 358        net->netdev_ops = &rndis_netdev_ops;
 359
 360        retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
 361        if (unlikely(retval < 0)) {
 362                /* it might not even be an RNDIS device!! */
 363                dev_err(&intf->dev, "RNDIS init failed, %d\n", retval);
 364                goto fail_and_release;
 365        }
 366        tmp = le32_to_cpu(u.init_c->max_transfer_size);
 367        if (tmp < dev->hard_mtu) {
 368                if (tmp <= net->hard_header_len) {
 369                        dev_err(&intf->dev,
 370                                "dev can't take %u byte packets (max %u)\n",
 371                                dev->hard_mtu, tmp);
 372                        retval = -EINVAL;
 373                        goto halt_fail_and_release;
 374                }
 375                dev_warn(&intf->dev,
 376                         "dev can't take %u byte packets (max %u), "
 377                         "adjusting MTU to %u\n",
 378                         dev->hard_mtu, tmp, tmp - net->hard_header_len);
 379                dev->hard_mtu = tmp;
 380                net->mtu = dev->hard_mtu - net->hard_header_len;
 381        }
 382
 383        /* REVISIT:  peripheral "alignment" request is ignored ... */
 384        dev_dbg(&intf->dev,
 385                "hard mtu %u (%u from dev), rx buflen %Zu, align %d\n",
 386                dev->hard_mtu, tmp, dev->rx_urb_size,
 387                1 << le32_to_cpu(u.init_c->packet_alignment));
 388
 389        /* module has some device initialization code needs to be done right
 390         * after RNDIS_INIT */
 391        if (dev->driver_info->early_init &&
 392                        dev->driver_info->early_init(dev) != 0)
 393                goto halt_fail_and_release;
 394
 395        /* Check physical medium */
 396        phym = NULL;
 397        reply_len = sizeof *phym;
 398        retval = rndis_query(dev, intf, u.buf, OID_GEN_PHYSICAL_MEDIUM,
 399                        0, (void **) &phym, &reply_len);
 400        if (retval != 0 || !phym) {
 401                /* OID is optional so don't fail here. */
 402                phym_unspec = RNDIS_PHYSICAL_MEDIUM_UNSPECIFIED;
 403                phym = &phym_unspec;
 404        }
 405        if ((flags & FLAG_RNDIS_PHYM_WIRELESS) &&
 406                        *phym != RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
 407                netif_dbg(dev, probe, dev->net,
 408                          "driver requires wireless physical medium, but device is not\n");
 409                retval = -ENODEV;
 410                goto halt_fail_and_release;
 411        }
 412        if ((flags & FLAG_RNDIS_PHYM_NOT_WIRELESS) &&
 413                        *phym == RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
 414                netif_dbg(dev, probe, dev->net,
 415                          "driver requires non-wireless physical medium, but device is wireless.\n");
 416                retval = -ENODEV;
 417                goto halt_fail_and_release;
 418        }
 419
 420        /* Get designated host ethernet address */
 421        reply_len = ETH_ALEN;
 422        retval = rndis_query(dev, intf, u.buf, OID_802_3_PERMANENT_ADDRESS,
 423                        48, (void **) &bp, &reply_len);
 424        if (unlikely(retval< 0)) {
 425                dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval);
 426                goto halt_fail_and_release;
 427        }
 428        memcpy(net->dev_addr, bp, ETH_ALEN);
 429        memcpy(net->perm_addr, bp, ETH_ALEN);
 430
 431        /* set a nonzero filter to enable data transfers */
 432        memset(u.set, 0, sizeof *u.set);
 433        u.set->msg_type = RNDIS_MSG_SET;
 434        u.set->msg_len = cpu_to_le32(4 + sizeof *u.set);
 435        u.set->oid = OID_GEN_CURRENT_PACKET_FILTER;
 436        u.set->len = cpu_to_le32(4);
 437        u.set->offset = cpu_to_le32((sizeof *u.set) - 8);
 438        *(__le32 *)(u.buf + sizeof *u.set) = RNDIS_DEFAULT_FILTER;
 439
 440        retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
 441        if (unlikely(retval < 0)) {
 442                dev_err(&intf->dev, "rndis set packet filter, %d\n", retval);
 443                goto halt_fail_and_release;
 444        }
 445
 446        retval = 0;
 447
 448        kfree(u.buf);
 449        return retval;
 450
 451halt_fail_and_release:
 452        memset(u.halt, 0, sizeof *u.halt);
 453        u.halt->msg_type = RNDIS_MSG_HALT;
 454        u.halt->msg_len = cpu_to_le32(sizeof *u.halt);
 455        (void) rndis_command(dev, (void *)u.halt, CONTROL_BUFFER_SIZE);
 456fail_and_release:
 457        usb_set_intfdata(info->data, NULL);
 458        usb_driver_release_interface(driver_of(intf), info->data);
 459        info->data = NULL;
 460fail:
 461        kfree(u.buf);
 462        return retval;
 463}
 464EXPORT_SYMBOL_GPL(generic_rndis_bind);
 465
 466static int rndis_bind(struct usbnet *dev, struct usb_interface *intf)
 467{
 468        return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS);
 469}
 470
 471void rndis_unbind(struct usbnet *dev, struct usb_interface *intf)
 472{
 473        struct rndis_halt       *halt;
 474
 475        /* try to clear any rndis state/activity (no i/o from stack!) */
 476        halt = kzalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
 477        if (halt) {
 478                halt->msg_type = RNDIS_MSG_HALT;
 479                halt->msg_len = cpu_to_le32(sizeof *halt);
 480                (void) rndis_command(dev, (void *)halt, CONTROL_BUFFER_SIZE);
 481                kfree(halt);
 482        }
 483
 484        usbnet_cdc_unbind(dev, intf);
 485}
 486EXPORT_SYMBOL_GPL(rndis_unbind);
 487
 488/*
 489 * DATA -- host must not write zlps
 490 */
 491int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 492{
 493        /* peripheral may have batched packets to us... */
 494        while (likely(skb->len)) {
 495                struct rndis_data_hdr   *hdr = (void *)skb->data;
 496                struct sk_buff          *skb2;
 497                u32                     msg_len, data_offset, data_len;
 498
 499                msg_len = le32_to_cpu(hdr->msg_len);
 500                data_offset = le32_to_cpu(hdr->data_offset);
 501                data_len = le32_to_cpu(hdr->data_len);
 502
 503                /* don't choke if we see oob, per-packet data, etc */
 504                if (unlikely(hdr->msg_type != RNDIS_MSG_PACKET ||
 505                             skb->len < msg_len ||
 506                             (data_offset + data_len + 8) > msg_len)) {
 507                        dev->net->stats.rx_frame_errors++;
 508                        netdev_dbg(dev->net, "bad rndis message %d/%d/%d/%d, len %d\n",
 509                                   le32_to_cpu(hdr->msg_type),
 510                                   msg_len, data_offset, data_len, skb->len);
 511                        return 0;
 512                }
 513                skb_pull(skb, 8 + data_offset);
 514
 515                /* at most one packet left? */
 516                if (likely((data_len - skb->len) <= sizeof *hdr)) {
 517                        skb_trim(skb, data_len);
 518                        break;
 519                }
 520
 521                /* try to return all the packets in the batch */
 522                skb2 = skb_clone(skb, GFP_ATOMIC);
 523                if (unlikely(!skb2))
 524                        break;
 525                skb_pull(skb, msg_len - sizeof *hdr);
 526                skb_trim(skb2, data_len);
 527                usbnet_skb_return(dev, skb2);
 528        }
 529
 530        /* caller will usbnet_skb_return the remaining packet */
 531        return 1;
 532}
 533EXPORT_SYMBOL_GPL(rndis_rx_fixup);
 534
 535struct sk_buff *
 536rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
 537{
 538        struct rndis_data_hdr   *hdr;
 539        struct sk_buff          *skb2;
 540        unsigned                len = skb->len;
 541
 542        if (likely(!skb_cloned(skb))) {
 543                int     room = skb_headroom(skb);
 544
 545                /* enough head room as-is? */
 546                if (unlikely((sizeof *hdr) <= room))
 547                        goto fill;
 548
 549                /* enough room, but needs to be readjusted? */
 550                room += skb_tailroom(skb);
 551                if (likely((sizeof *hdr) <= room)) {
 552                        skb->data = memmove(skb->head + sizeof *hdr,
 553                                            skb->data, len);
 554                        skb_set_tail_pointer(skb, len);
 555                        goto fill;
 556                }
 557        }
 558
 559        /* create a new skb, with the correct size (and tailpad) */
 560        skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags);
 561        dev_kfree_skb_any(skb);
 562        if (unlikely(!skb2))
 563                return skb2;
 564        skb = skb2;
 565
 566        /* fill out the RNDIS header.  we won't bother trying to batch
 567         * packets; Linux minimizes wasted bandwidth through tx queues.
 568         */
 569fill:
 570        hdr = (void *) __skb_push(skb, sizeof *hdr);
 571        memset(hdr, 0, sizeof *hdr);
 572        hdr->msg_type = RNDIS_MSG_PACKET;
 573        hdr->msg_len = cpu_to_le32(skb->len);
 574        hdr->data_offset = cpu_to_le32(sizeof(*hdr) - 8);
 575        hdr->data_len = cpu_to_le32(len);
 576
 577        /* FIXME make the last packet always be short ... */
 578        return skb;
 579}
 580EXPORT_SYMBOL_GPL(rndis_tx_fixup);
 581
 582
 583static const struct driver_info rndis_info = {
 584        .description =  "RNDIS device",
 585        .flags =        FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
 586        .bind =         rndis_bind,
 587        .unbind =       rndis_unbind,
 588        .status =       rndis_status,
 589        .rx_fixup =     rndis_rx_fixup,
 590        .tx_fixup =     rndis_tx_fixup,
 591};
 592
 593static const struct driver_info rndis_poll_status_info = {
 594        .description =  "RNDIS device (poll status before control)",
 595        .flags =        FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
 596        .data =         RNDIS_DRIVER_DATA_POLL_STATUS,
 597        .bind =         rndis_bind,
 598        .unbind =       rndis_unbind,
 599        .status =       rndis_status,
 600        .rx_fixup =     rndis_rx_fixup,
 601        .tx_fixup =     rndis_tx_fixup,
 602};
 603
 604/*-------------------------------------------------------------------------*/
 605
 606static const struct usb_device_id       products [] = {
 607{
 608        /* 2Wire HomePortal 1000SW */
 609        USB_DEVICE_AND_INTERFACE_INFO(0x1630, 0x0042,
 610                                      USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
 611        .driver_info = (unsigned long) &rndis_poll_status_info,
 612}, {
 613        /* RNDIS is MSFT's un-official variant of CDC ACM */
 614        USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
 615        .driver_info = (unsigned long) &rndis_info,
 616}, {
 617        /* "ActiveSync" is an undocumented variant of RNDIS, used in WM5 */
 618        USB_INTERFACE_INFO(USB_CLASS_MISC, 1, 1),
 619        .driver_info = (unsigned long) &rndis_poll_status_info,
 620}, {
 621        /* RNDIS for tethering */
 622        USB_INTERFACE_INFO(USB_CLASS_WIRELESS_CONTROLLER, 1, 3),
 623        .driver_info = (unsigned long) &rndis_info,
 624},
 625        { },            // END
 626};
 627MODULE_DEVICE_TABLE(usb, products);
 628
 629static struct usb_driver rndis_driver = {
 630        .name =         "rndis_host",
 631        .id_table =     products,
 632        .probe =        usbnet_probe,
 633        .disconnect =   usbnet_disconnect,
 634        .suspend =      usbnet_suspend,
 635        .resume =       usbnet_resume,
 636};
 637
 638module_usb_driver(rndis_driver);
 639
 640MODULE_AUTHOR("David Brownell");
 641MODULE_DESCRIPTION("USB Host side RNDIS driver");
 642MODULE_LICENSE("GPL");
 643