root/drivers/net/usb/cdc_mbim.c

DEFINITIONS

1. cdc_mbim_manage_power
2. cdc_mbim_wdm_manage_power
3. cdc_mbim_rx_add_vid
4. cdc_mbim_rx_kill_vid
5. cdc_mbim_set_ctrlalt
6. cdc_mbim_bind
7. cdc_mbim_unbind
8. is_ip_proto
9. cdc_mbim_tx_fixup
10. do_neigh_solicit
11. is_neigh_solicit
12. cdc_mbim_process_dgram
13. cdc_mbim_rx_fixup
14. cdc_mbim_suspend
15. cdc_mbim_resume

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2012  Smith Micro Software, Inc.
   4  * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
   5  *
   6  * This driver is based on and reuse most of cdc_ncm, which is
   7  * Copyright (C) ST-Ericsson 2010-2012
   8  */
   9 
  10 #include <linux/module.h>
  11 #include <linux/netdevice.h>
  12 #include <linux/ethtool.h>
  13 #include <linux/if_vlan.h>
  14 #include <linux/ip.h>
  15 #include <linux/mii.h>
  16 #include <linux/usb.h>
  17 #include <linux/usb/cdc.h>
  18 #include <linux/usb/usbnet.h>
  19 #include <linux/usb/cdc-wdm.h>
  20 #include <linux/usb/cdc_ncm.h>
  21 #include <net/ipv6.h>
  22 #include <net/addrconf.h>
  23 #include <net/ipv6_stubs.h>
  24 
  25 /* alternative VLAN for IP session 0 if not untagged */
  26 #define MBIM_IPS0_VID   4094
  27 
  28 /* driver specific data - must match cdc_ncm usage */
  29 struct cdc_mbim_state {
  30         struct cdc_ncm_ctx *ctx;
  31         atomic_t pmcount;
  32         struct usb_driver *subdriver;
  33         unsigned long _unused;
  34         unsigned long flags;
  35 };
  36 
  37 /* flags for the cdc_mbim_state.flags field */
  38 enum cdc_mbim_flags {
  39         FLAG_IPS0_VLAN = 1 << 0,        /* IP session 0 is tagged  */
  40 };
  41 
  42 /* using a counter to merge subdriver requests with our own into a combined state */
  43 static int cdc_mbim_manage_power(struct usbnet *dev, int on)
  44 {
  45         struct cdc_mbim_state *info = (void *)&dev->data;
  46         int rv = 0;
  47 
  48         dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
  49 
  50         if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
  51                 /* need autopm_get/put here to ensure the usbcore sees the new value */
  52                 rv = usb_autopm_get_interface(dev->intf);
  53                 dev->intf->needs_remote_wakeup = on;
  54                 if (!rv)
  55                         usb_autopm_put_interface(dev->intf);
  56         }
  57         return 0;
  58 }
  59 
  60 static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
  61 {
  62         struct usbnet *dev = usb_get_intfdata(intf);
  63 
  64         /* can be called while disconnecting */
  65         if (!dev)
  66                 return 0;
  67 
  68         return cdc_mbim_manage_power(dev, status);
  69 }
  70 
  71 static int cdc_mbim_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
  72 {
  73         struct usbnet *dev = netdev_priv(netdev);
  74         struct cdc_mbim_state *info = (void *)&dev->data;
  75 
  76         /* creation of this VLAN is a request to tag IP session 0 */
  77         if (vid == MBIM_IPS0_VID)
  78                 info->flags |= FLAG_IPS0_VLAN;
  79         else
  80                 if (vid >= 512) /* we don't map these to MBIM session */
  81                         return -EINVAL;
  82         return 0;
  83 }
  84 
  85 static int cdc_mbim_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
  86 {
  87         struct usbnet *dev = netdev_priv(netdev);
  88         struct cdc_mbim_state *info = (void *)&dev->data;
  89 
  90         /* this is a request for an untagged IP session 0 */
  91         if (vid == MBIM_IPS0_VID)
  92                 info->flags &= ~FLAG_IPS0_VLAN;
  93         return 0;
  94 }
  95 
  96 static const struct net_device_ops cdc_mbim_netdev_ops = {
  97         .ndo_open             = usbnet_open,
  98         .ndo_stop             = usbnet_stop,
  99         .ndo_start_xmit       = usbnet_start_xmit,
 100         .ndo_tx_timeout       = usbnet_tx_timeout,
 101         .ndo_get_stats64      = usbnet_get_stats64,
 102         .ndo_change_mtu       = cdc_ncm_change_mtu,
 103         .ndo_set_mac_address  = eth_mac_addr,
 104         .ndo_validate_addr    = eth_validate_addr,
 105         .ndo_vlan_rx_add_vid  = cdc_mbim_rx_add_vid,
 106         .ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
 107 };
 108 
 109 /* Change the control interface altsetting and update the .driver_info
 110  * pointer if the matching entry after changing class codes points to
 111  * a different struct
 112  */
 113 static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
 114 {
 115         struct usb_driver *driver = to_usb_driver(intf->dev.driver);
 116         const struct usb_device_id *id;
 117         struct driver_info *info;
 118         int ret;
 119 
 120         ret = usb_set_interface(dev->udev,
 121                                 intf->cur_altsetting->desc.bInterfaceNumber,
 122                                 alt);
 123         if (ret)
 124                 return ret;
 125 
 126         id = usb_match_id(intf, driver->id_table);
 127         if (!id)
 128                 return -ENODEV;
 129 
 130         info = (struct driver_info *)id->driver_info;
 131         if (info != dev->driver_info) {
 132                 dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
 133                         info->description);
 134                 dev->driver_info = info;
 135         }
 136         return 0;
 137 }
 138 
 139 static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
 140 {
 141         struct cdc_ncm_ctx *ctx;
 142         struct usb_driver *subdriver = ERR_PTR(-ENODEV);
 143         int ret = -ENODEV;
 144         u8 data_altsetting = 1;
 145         struct cdc_mbim_state *info = (void *)&dev->data;
 146 
 147         /* should we change control altsetting on a NCM/MBIM function? */
 148         if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
 149                 data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
 150                 ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
 151                 if (ret)
 152                         goto err;
 153                 ret = -ENODEV;
 154         }
 155 
 156         /* we will hit this for NCM/MBIM functions if prefer_mbim is false */
 157         if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
 158                 goto err;
 159 
 160         ret = cdc_ncm_bind_common(dev, intf, data_altsetting, dev->driver_info->data);
 161         if (ret)
 162                 goto err;
 163 
 164         ctx = info->ctx;
 165 
 166         /* The MBIM descriptor and the status endpoint are required */
 167         if (ctx->mbim_desc && dev->status)
 168                 subdriver = usb_cdc_wdm_register(ctx->control,
 169                                                  &dev->status->desc,
 170                                                  le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
 171                                                  cdc_mbim_wdm_manage_power);
 172         if (IS_ERR(subdriver)) {
 173                 ret = PTR_ERR(subdriver);
 174                 cdc_ncm_unbind(dev, intf);
 175                 goto err;
 176         }
 177 
 178         /* can't let usbnet use the interrupt endpoint */
 179         dev->status = NULL;
 180         info->subdriver = subdriver;
 181 
 182         /* MBIM cannot do ARP */
 183         dev->net->flags |= IFF_NOARP;
 184 
 185         /* no need to put the VLAN tci in the packet headers */
 186         dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
 187 
 188         /* monitor VLAN additions and removals */
 189         dev->net->netdev_ops = &cdc_mbim_netdev_ops;
 190 err:
 191         return ret;
 192 }
 193 
 194 static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
 195 {
 196         struct cdc_mbim_state *info = (void *)&dev->data;
 197         struct cdc_ncm_ctx *ctx = info->ctx;
 198 
 199         /* disconnect subdriver from control interface */
 200         if (info->subdriver && info->subdriver->disconnect)
 201                 info->subdriver->disconnect(ctx->control);
 202         info->subdriver = NULL;
 203 
 204         /* let NCM unbind clean up both control and data interface */
 205         cdc_ncm_unbind(dev, intf);
 206 }
 207 
 208 /* verify that the ethernet protocol is IPv4 or IPv6 */
 209 static bool is_ip_proto(__be16 proto)
 210 {
 211         switch (proto) {
 212         case htons(ETH_P_IP):
 213         case htons(ETH_P_IPV6):
 214                 return true;
 215         }
 216         return false;
 217 }
 218 
 219 static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
 220 {
 221         struct sk_buff *skb_out;
 222         struct cdc_mbim_state *info = (void *)&dev->data;
 223         struct cdc_ncm_ctx *ctx = info->ctx;
 224         __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
 225         u16 tci = 0;
 226         bool is_ip;
 227         u8 *c;
 228 
 229         if (!ctx)
 230                 goto error;
 231 
 232         if (skb) {
 233                 if (skb->len <= ETH_HLEN)
 234                         goto error;
 235 
 236                 /* Some applications using e.g. packet sockets will
 237                  * bypass the VLAN acceleration and create tagged
 238                  * ethernet frames directly.  We primarily look for
 239                  * the accelerated out-of-band tag, but fall back if
 240                  * required
 241                  */
 242                 skb_reset_mac_header(skb);
 243                 if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
 244                     __vlan_get_tag(skb, &tci) == 0) {
 245                         is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
 246                         skb_pull(skb, VLAN_ETH_HLEN);
 247                 } else {
 248                         is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
 249                         skb_pull(skb, ETH_HLEN);
 250                 }
 251 
 252                 /* Is IP session <0> tagged too? */
 253                 if (info->flags & FLAG_IPS0_VLAN) {
 254                         /* drop all untagged packets */
 255                         if (!tci)
 256                                 goto error;
 257                         /* map MBIM_IPS0_VID to IPS<0> */
 258                         if (tci == MBIM_IPS0_VID)
 259                                 tci = 0;
 260                 }
 261 
 262                 /* mapping VLANs to MBIM sessions:
 263                  *   no tag     => IPS session <0> if !FLAG_IPS0_VLAN
 264                  *   1 - 255    => IPS session <vlanid>
 265                  *   256 - 511  => DSS session <vlanid - 256>
 266                  *   512 - 4093 => unsupported, drop
 267                  *   4094       => IPS session <0> if FLAG_IPS0_VLAN
 268                  */
 269 
 270                 switch (tci & 0x0f00) {
 271                 case 0x0000: /* VLAN ID 0 - 255 */
 272                         if (!is_ip)
 273                                 goto error;
 274                         c = (u8 *)&sign;
 275                         c[3] = tci;
 276                         break;
 277                 case 0x0100: /* VLAN ID 256 - 511 */
 278                         if (is_ip)
 279                                 goto error;
 280                         sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
 281                         c = (u8 *)&sign;
 282                         c[3] = tci;
 283                         break;
 284                 default:
 285                         netif_err(dev, tx_err, dev->net,
 286                                   "unsupported tci=0x%04x\n", tci);
 287                         goto error;
 288                 }
 289         }
 290 
 291         spin_lock_bh(&ctx->mtx);
 292         skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
 293         spin_unlock_bh(&ctx->mtx);
 294         return skb_out;
 295 
 296 error:
 297         if (skb)
 298                 dev_kfree_skb_any(skb);
 299 
 300         return NULL;
 301 }
 302 
 303 /* Some devices are known to send Neigbor Solicitation messages and
 304  * require Neigbor Advertisement replies.  The IPv6 core will not
 305  * respond since IFF_NOARP is set, so we must handle them ourselves.
 306  */
 307 static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
 308 {
 309         struct ipv6hdr *iph = (void *)buf;
 310         struct nd_msg *msg = (void *)(iph + 1);
 311         struct net_device *netdev;
 312         struct inet6_dev *in6_dev;
 313         bool is_router;
 314 
 315         /* we'll only respond to requests from unicast addresses to
 316          * our solicited node addresses.
 317          */
 318         if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
 319             !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
 320                 return;
 321 
 322         /* need to send the NA on the VLAN dev, if any */
 323         rcu_read_lock();
 324         if (tci) {
 325                 netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
 326                                                   tci);
 327                 if (!netdev) {
 328                         rcu_read_unlock();
 329                         return;
 330                 }
 331         } else {
 332                 netdev = dev->net;
 333         }
 334         dev_hold(netdev);
 335         rcu_read_unlock();
 336 
 337         in6_dev = in6_dev_get(netdev);
 338         if (!in6_dev)
 339                 goto out;
 340         is_router = !!in6_dev->cnf.forwarding;
 341         in6_dev_put(in6_dev);
 342 
 343         /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
 344         ipv6_stub->ndisc_send_na(netdev, &iph->saddr, &msg->target,
 345                                  is_router /* router */,
 346                                  true /* solicited */,
 347                                  false /* override */,
 348                                  true /* inc_opt */);
 349 out:
 350         dev_put(netdev);
 351 }
 352 
 353 static bool is_neigh_solicit(u8 *buf, size_t len)
 354 {
 355         struct ipv6hdr *iph = (void *)buf;
 356         struct nd_msg *msg = (void *)(iph + 1);
 357 
 358         return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
 359                 iph->nexthdr == IPPROTO_ICMPV6 &&
 360                 msg->icmph.icmp6_code == 0 &&
 361                 msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
 362 }
 363 
 364 
 365 static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
 366 {
 367         __be16 proto = htons(ETH_P_802_3);
 368         struct sk_buff *skb = NULL;
 369 
 370         if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
 371                 if (len < sizeof(struct iphdr))
 372                         goto err;
 373 
 374                 switch (*buf & 0xf0) {
 375                 case 0x40:
 376                         proto = htons(ETH_P_IP);
 377                         break;
 378                 case 0x60:
 379                         if (is_neigh_solicit(buf, len))
 380                                 do_neigh_solicit(dev, buf, tci);
 381                         proto = htons(ETH_P_IPV6);
 382                         break;
 383                 default:
 384                         goto err;
 385                 }
 386         }
 387 
 388         skb = netdev_alloc_skb_ip_align(dev->net,  len + ETH_HLEN);
 389         if (!skb)
 390                 goto err;
 391 
 392         /* add an ethernet header */
 393         skb_put(skb, ETH_HLEN);
 394         skb_reset_mac_header(skb);
 395         eth_hdr(skb)->h_proto = proto;
 396         eth_zero_addr(eth_hdr(skb)->h_source);
 397         memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
 398 
 399         /* add datagram */
 400         skb_put_data(skb, buf, len);
 401 
 402         /* map MBIM session to VLAN */
 403         if (tci)
 404                 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
 405 err:
 406         return skb;
 407 }
 408 
 409 static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
 410 {
 411         struct sk_buff *skb;
 412         struct cdc_mbim_state *info = (void *)&dev->data;
 413         struct cdc_ncm_ctx *ctx = info->ctx;
 414         int len;
 415         int nframes;
 416         int x;
 417         int offset;
 418         struct usb_cdc_ncm_ndp16 *ndp16;
 419         struct usb_cdc_ncm_dpe16 *dpe16;
 420         int ndpoffset;
 421         int loopcount = 50; /* arbitrary max preventing infinite loop */
 422         u32 payload = 0;
 423         u8 *c;
 424         u16 tci;
 425 
 426         ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
 427         if (ndpoffset < 0)
 428                 goto error;
 429 
 430 next_ndp:
 431         nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
 432         if (nframes < 0)
 433                 goto error;
 434 
 435         ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
 436 
 437         switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
 438         case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
 439                 c = (u8 *)&ndp16->dwSignature;
 440                 tci = c[3];
 441                 /* tag IPS<0> packets too if MBIM_IPS0_VID exists */
 442                 if (!tci && info->flags & FLAG_IPS0_VLAN)
 443                         tci = MBIM_IPS0_VID;
 444                 break;
 445         case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
 446                 c = (u8 *)&ndp16->dwSignature;
 447                 tci = c[3] + 256;
 448                 break;
 449         default:
 450                 netif_dbg(dev, rx_err, dev->net,
 451                           "unsupported NDP signature <0x%08x>\n",
 452                           le32_to_cpu(ndp16->dwSignature));
 453                 goto err_ndp;
 454 
 455         }
 456 
 457         dpe16 = ndp16->dpe16;
 458         for (x = 0; x < nframes; x++, dpe16++) {
 459                 offset = le16_to_cpu(dpe16->wDatagramIndex);
 460                 len = le16_to_cpu(dpe16->wDatagramLength);
 461 
 462                 /*
 463                  * CDC NCM ch. 3.7
 464                  * All entries after first NULL entry are to be ignored
 465                  */
 466                 if ((offset == 0) || (len == 0)) {
 467                         if (!x)
 468                                 goto err_ndp; /* empty NTB */
 469                         break;
 470                 }
 471 
 472                 /* sanity checking */
 473                 if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
 474                         netif_dbg(dev, rx_err, dev->net,
 475                                   "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
 476                                   x, offset, len, skb_in);
 477                         if (!x)
 478                                 goto err_ndp;
 479                         break;
 480                 } else {
 481                         skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
 482                         if (!skb)
 483                                 goto error;
 484                         usbnet_skb_return(dev, skb);
 485                         payload += len; /* count payload bytes in this NTB */
 486                 }
 487         }
 488 err_ndp:
 489         /* are there more NDPs to process? */
 490         ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
 491         if (ndpoffset && loopcount--)
 492                 goto next_ndp;
 493 
 494         /* update stats */
 495         ctx->rx_overhead += skb_in->len - payload;
 496         ctx->rx_ntbs++;
 497 
 498         return 1;
 499 error:
 500         return 0;
 501 }
 502 
 503 static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
 504 {
 505         int ret = -ENODEV;
 506         struct usbnet *dev = usb_get_intfdata(intf);
 507         struct cdc_mbim_state *info = (void *)&dev->data;
 508         struct cdc_ncm_ctx *ctx = info->ctx;
 509 
 510         if (!ctx)
 511                 goto error;
 512 
 513         /*
 514          * Both usbnet_suspend() and subdriver->suspend() MUST return 0
 515          * in system sleep context, otherwise, the resume callback has
 516          * to recover device from previous suspend failure.
 517          */
 518         ret = usbnet_suspend(intf, message);
 519         if (ret < 0)
 520                 goto error;
 521 
 522         if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
 523                 ret = info->subdriver->suspend(intf, message);
 524         if (ret < 0)
 525                 usbnet_resume(intf);
 526 
 527 error:
 528         return ret;
 529 }
 530 
 531 static int cdc_mbim_resume(struct usb_interface *intf)
 532 {
 533         int  ret = 0;
 534         struct usbnet *dev = usb_get_intfdata(intf);
 535         struct cdc_mbim_state *info = (void *)&dev->data;
 536         struct cdc_ncm_ctx *ctx = info->ctx;
 537         bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
 538 
 539         if (callsub)
 540                 ret = info->subdriver->resume(intf);
 541         if (ret < 0)
 542                 goto err;
 543         ret = usbnet_resume(intf);
 544         if (ret < 0 && callsub)
 545                 info->subdriver->suspend(intf, PMSG_SUSPEND);
 546 err:
 547         return ret;
 548 }
 549 
 550 static const struct driver_info cdc_mbim_info = {
 551         .description = "CDC MBIM",
 552         .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
 553         .bind = cdc_mbim_bind,
 554         .unbind = cdc_mbim_unbind,
 555         .manage_power = cdc_mbim_manage_power,
 556         .rx_fixup = cdc_mbim_rx_fixup,
 557         .tx_fixup = cdc_mbim_tx_fixup,
 558 };
 559 
 560 /* MBIM and NCM devices should not need a ZLP after NTBs with
 561  * dwNtbOutMaxSize length. Nevertheless, a number of devices from
 562  * different vendor IDs will fail unless we send ZLPs, forcing us
 563  * to make this the default.
 564  *
 565  * This default may cause a performance penalty for spec conforming
 566  * devices wanting to take advantage of optimizations possible without
 567  * ZLPs.  A whitelist is added in an attempt to avoid this for devices
 568  * known to conform to the MBIM specification.
 569  *
 570  * All known devices supporting NCM compatibility mode are also
 571  * conforming to the NCM and MBIM specifications. For this reason, the
 572  * NCM subclass entry is also in the ZLP whitelist.
 573  */
 574 static const struct driver_info cdc_mbim_info_zlp = {
 575         .description = "CDC MBIM",
 576         .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
 577         .bind = cdc_mbim_bind,
 578         .unbind = cdc_mbim_unbind,
 579         .manage_power = cdc_mbim_manage_power,
 580         .rx_fixup = cdc_mbim_rx_fixup,
 581         .tx_fixup = cdc_mbim_tx_fixup,
 582 };
 583 
 584 /* The spefication explicitly allows NDPs to be placed anywhere in the
 585  * frame, but some devices fail unless the NDP is placed after the IP
 586  * packets.  Using the CDC_NCM_FLAG_NDP_TO_END flags to force this
 587  * behaviour.
 588  *
 589  * Note: The current implementation of this feature restricts each NTB
 590  * to a single NDP, implying that multiplexed sessions cannot share an
 591  * NTB. This might affect performace for multiplexed sessions.
 592  */
 593 static const struct driver_info cdc_mbim_info_ndp_to_end = {
 594         .description = "CDC MBIM",
 595         .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
 596         .bind = cdc_mbim_bind,
 597         .unbind = cdc_mbim_unbind,
 598         .manage_power = cdc_mbim_manage_power,
 599         .rx_fixup = cdc_mbim_rx_fixup,
 600         .tx_fixup = cdc_mbim_tx_fixup,
 601         .data = CDC_NCM_FLAG_NDP_TO_END,
 602 };
 603 
 604 /* Some modems (e.g. Telit LE922A6) do not work properly with altsetting
 605  * toggle done in cdc_ncm_bind_common. CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
 606  * flag is used to avoid this procedure.
 607  */
 608 static const struct driver_info cdc_mbim_info_avoid_altsetting_toggle = {
 609         .description = "CDC MBIM",
 610         .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
 611         .bind = cdc_mbim_bind,
 612         .unbind = cdc_mbim_unbind,
 613         .manage_power = cdc_mbim_manage_power,
 614         .rx_fixup = cdc_mbim_rx_fixup,
 615         .tx_fixup = cdc_mbim_tx_fixup,
 616         .data = CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE,
 617 };
 618 
 619 static const struct usb_device_id mbim_devs[] = {
 620         /* This duplicate NCM entry is intentional. MBIM devices can
 621          * be disguised as NCM by default, and this is necessary to
 622          * allow us to bind the correct driver_info to such devices.
 623          *
 624          * bind() will sort out this for us, selecting the correct
 625          * entry and reject the other
 626          */
 627         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
 628           .driver_info = (unsigned long)&cdc_mbim_info,
 629         },
 630         /* ZLP conformance whitelist: All Ericsson MBIM devices */
 631         { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 632           .driver_info = (unsigned long)&cdc_mbim_info,
 633         },
 634 
 635         /* Some Huawei devices, ME906s-158 (12d1:15c1) and E3372
 636          * (12d1:157d), are known to fail unless the NDP is placed
 637          * after the IP packets.  Applying the quirk to all Huawei
 638          * devices is broader than necessary, but harmless.
 639          */
 640         { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 641           .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
 642         },
 643 
 644         /* The HP lt4132 (03f0:a31d) is a rebranded Huawei ME906s-158,
 645          * therefore it too requires the above "NDP to end" quirk.
 646          */
 647         { USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 648           .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
 649         },
 650 
 651         /* Telit LE922A6 in MBIM composition */
 652         { USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x1041, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 653           .driver_info = (unsigned long)&cdc_mbim_info_avoid_altsetting_toggle,
 654         },
 655 
 656         /* default entry */
 657         { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
 658           .driver_info = (unsigned long)&cdc_mbim_info_zlp,
 659         },
 660         {
 661         },
 662 };
 663 MODULE_DEVICE_TABLE(usb, mbim_devs);
 664 
 665 static struct usb_driver cdc_mbim_driver = {
 666         .name = "cdc_mbim",
 667         .id_table = mbim_devs,
 668         .probe = usbnet_probe,
 669         .disconnect = usbnet_disconnect,
 670         .suspend = cdc_mbim_suspend,
 671         .resume = cdc_mbim_resume,
 672         .reset_resume = cdc_mbim_resume,
 673         .supports_autosuspend = 1,
 674         .disable_hub_initiated_lpm = 1,
 675 };
 676 module_usb_driver(cdc_mbim_driver);
 677 
 678 MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
 679 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
 680 MODULE_DESCRIPTION("USB CDC MBIM host driver");
 681 MODULE_LICENSE("GPL");