linux/drivers/net/usb/cdc_mbim.c
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   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 */
  29struct 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 */
  38enum 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 */
  43static 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
  60static 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
  71static 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
  85static 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
  96static 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 */
 113static 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
 139static 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;
 190err:
 191        return ret;
 192}
 193
 194static 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 */
 209static 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
 219static 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
 296error:
 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 */
 307static 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 */);
 349out:
 350        dev_put(netdev);
 351}
 352
 353static 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
 365static 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);
 405err:
 406        return skb;
 407}
 408
 409static 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
 430next_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        }
 488err_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;
 499error:
 500        return 0;
 501}
 502
 503static 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
 527error:
 528        return ret;
 529}
 530
 531static 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);
 546err:
 547        return ret;
 548}
 549
 550static 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 */
 574static 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 */
 593static 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 */
 608static 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
 619static 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};
 663MODULE_DEVICE_TABLE(usb, mbim_devs);
 664
 665static 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};
 676module_usb_driver(cdc_mbim_driver);
 677
 678MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
 679MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
 680MODULE_DESCRIPTION("USB CDC MBIM host driver");
 681MODULE_LICENSE("GPL");
 682