/* * Copyright (c) 2012 Smith Micro Software, Inc. * Copyright (c) 2012 Bjørn Mork * * This driver is based on and reuse most of cdc_ncm, which is * Copyright (C) ST-Ericsson 2010-2012 * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include /* driver specific data - must match cdc_ncm usage */ struct cdc_mbim_state { struct cdc_ncm_ctx *ctx; atomic_t pmcount; struct usb_driver *subdriver; struct usb_interface *control; struct usb_interface *data; }; /* using a counter to merge subdriver requests with our own into a combined state */ static int cdc_mbim_manage_power(struct usbnet *dev, int on) { struct cdc_mbim_state *info = (void *)&dev->data; int rv = 0; dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on); if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) { /* need autopm_get/put here to ensure the usbcore sees the new value */ rv = usb_autopm_get_interface(dev->intf); dev->intf->needs_remote_wakeup = on; if (!rv) usb_autopm_put_interface(dev->intf); } return 0; } static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status) { struct usbnet *dev = usb_get_intfdata(intf); /* can be called while disconnecting */ if (!dev) return 0; return cdc_mbim_manage_power(dev, status); } static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf) { struct cdc_ncm_ctx *ctx; struct usb_driver *subdriver = ERR_PTR(-ENODEV); int ret = -ENODEV; u8 data_altsetting = cdc_ncm_select_altsetting(dev, intf); struct cdc_mbim_state *info = (void *)&dev->data; /* Probably NCM, defer for cdc_ncm_bind */ if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) goto err; ret = cdc_ncm_bind_common(dev, intf, data_altsetting); if (ret) goto err; ctx = info->ctx; /* The MBIM descriptor and the status endpoint are required */ if (ctx->mbim_desc && dev->status) subdriver = usb_cdc_wdm_register(ctx->control, &dev->status->desc, le16_to_cpu(ctx->mbim_desc->wMaxControlMessage), cdc_mbim_wdm_manage_power); if (IS_ERR(subdriver)) { ret = PTR_ERR(subdriver); cdc_ncm_unbind(dev, intf); goto err; } /* can't let usbnet use the interrupt endpoint */ dev->status = NULL; info->subdriver = subdriver; /* MBIM cannot do ARP */ dev->net->flags |= IFF_NOARP; /* no need to put the VLAN tci in the packet headers */ dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX; err: return ret; } static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf) { struct cdc_mbim_state *info = (void *)&dev->data; struct cdc_ncm_ctx *ctx = info->ctx; /* disconnect subdriver from control interface */ if (info->subdriver && info->subdriver->disconnect) info->subdriver->disconnect(ctx->control); info->subdriver = NULL; /* let NCM unbind clean up both control and data interface */ cdc_ncm_unbind(dev, intf); } /* verify that the ethernet protocol is IPv4 or IPv6 */ static bool is_ip_proto(__be16 proto) { switch (proto) { case htons(ETH_P_IP): case htons(ETH_P_IPV6): return true; } return false; } static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) { struct sk_buff *skb_out; struct cdc_mbim_state *info = (void *)&dev->data; struct cdc_ncm_ctx *ctx = info->ctx; __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN); u16 tci = 0; bool is_ip; u8 *c; if (!ctx) goto error; if (skb) { if (skb->len <= ETH_HLEN) goto error; /* Some applications using e.g. packet sockets will * bypass the VLAN acceleration and create tagged * ethernet frames directly. We primarily look for * the accelerated out-of-band tag, but fall back if * required */ skb_reset_mac_header(skb); if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN && __vlan_get_tag(skb, &tci) == 0) { is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto); skb_pull(skb, VLAN_ETH_HLEN); } else { is_ip = is_ip_proto(eth_hdr(skb)->h_proto); skb_pull(skb, ETH_HLEN); } /* mapping VLANs to MBIM sessions: * no tag => IPS session <0> * 1 - 255 => IPS session * 256 - 511 => DSS session * 512 - 4095 => unsupported, drop */ switch (tci & 0x0f00) { case 0x0000: /* VLAN ID 0 - 255 */ if (!is_ip) goto error; c = (u8 *)&sign; c[3] = tci; break; case 0x0100: /* VLAN ID 256 - 511 */ sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN); c = (u8 *)&sign; c[3] = tci; break; default: netif_err(dev, tx_err, dev->net, "unsupported tci=0x%04x\n", tci); goto error; } } spin_lock_bh(&ctx->mtx); skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign); spin_unlock_bh(&ctx->mtx); return skb_out; error: if (skb) dev_kfree_skb_any(skb); return NULL; } /* Some devices are known to send Neigbor Solicitation messages and * require Neigbor Advertisement replies. The IPv6 core will not * respond since IFF_NOARP is set, so we must handle them ourselves. */ static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci) { struct ipv6hdr *iph = (void *)buf; struct nd_msg *msg = (void *)(iph + 1); struct net_device *netdev; struct inet6_dev *in6_dev; bool is_router; /* we'll only respond to requests from unicast addresses to * our solicited node addresses. */ if (!ipv6_addr_is_solict_mult(&iph->daddr) || !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST)) return; /* need to send the NA on the VLAN dev, if any */ rcu_read_lock(); if (tci) { netdev = __vlan_find_dev_deep(dev->net, htons(ETH_P_8021Q), tci); if (!netdev) { rcu_read_unlock(); return; } } else { netdev = dev->net; } dev_hold(netdev); rcu_read_unlock(); in6_dev = in6_dev_get(netdev); if (!in6_dev) goto out; is_router = !!in6_dev->cnf.forwarding; in6_dev_put(in6_dev); /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */ ipv6_stub->ndisc_send_na(netdev, NULL, &iph->saddr, &msg->target, is_router /* router */, true /* solicited */, false /* override */, true /* inc_opt */); out: dev_put(netdev); } static bool is_neigh_solicit(u8 *buf, size_t len) { struct ipv6hdr *iph = (void *)buf; struct nd_msg *msg = (void *)(iph + 1); return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) && iph->nexthdr == IPPROTO_ICMPV6 && msg->icmph.icmp6_code == 0 && msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION); } static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci) { __be16 proto = htons(ETH_P_802_3); struct sk_buff *skb = NULL; if (tci < 256) { /* IPS session? */ if (len < sizeof(struct iphdr)) goto err; switch (*buf & 0xf0) { case 0x40: proto = htons(ETH_P_IP); break; case 0x60: if (is_neigh_solicit(buf, len)) do_neigh_solicit(dev, buf, tci); proto = htons(ETH_P_IPV6); break; default: goto err; } } skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN); if (!skb) goto err; /* add an ethernet header */ skb_put(skb, ETH_HLEN); skb_reset_mac_header(skb); eth_hdr(skb)->h_proto = proto; memset(eth_hdr(skb)->h_source, 0, ETH_ALEN); memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN); /* add datagram */ memcpy(skb_put(skb, len), buf, len); /* map MBIM session to VLAN */ if (tci) vlan_put_tag(skb, htons(ETH_P_8021Q), tci); err: return skb; } static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in) { struct sk_buff *skb; struct cdc_mbim_state *info = (void *)&dev->data; struct cdc_ncm_ctx *ctx = info->ctx; int len; int nframes; int x; int offset; struct usb_cdc_ncm_ndp16 *ndp16; struct usb_cdc_ncm_dpe16 *dpe16; int ndpoffset; int loopcount = 50; /* arbitrary max preventing infinite loop */ u8 *c; u16 tci; ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in); if (ndpoffset < 0) goto error; next_ndp: nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset); if (nframes < 0) goto error; ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset); switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) { case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN): c = (u8 *)&ndp16->dwSignature; tci = c[3]; break; case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN): c = (u8 *)&ndp16->dwSignature; tci = c[3] + 256; break; default: netif_dbg(dev, rx_err, dev->net, "unsupported NDP signature <0x%08x>\n", le32_to_cpu(ndp16->dwSignature)); goto err_ndp; } dpe16 = ndp16->dpe16; for (x = 0; x < nframes; x++, dpe16++) { offset = le16_to_cpu(dpe16->wDatagramIndex); len = le16_to_cpu(dpe16->wDatagramLength); /* * CDC NCM ch. 3.7 * All entries after first NULL entry are to be ignored */ if ((offset == 0) || (len == 0)) { if (!x) goto err_ndp; /* empty NTB */ break; } /* sanity checking */ if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) { netif_dbg(dev, rx_err, dev->net, "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n", x, offset, len, skb_in); if (!x) goto err_ndp; break; } else { skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci); if (!skb) goto error; usbnet_skb_return(dev, skb); } } err_ndp: /* are there more NDPs to process? */ ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex); if (ndpoffset && loopcount--) goto next_ndp; return 1; error: return 0; } static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message) { int ret = -ENODEV; struct usbnet *dev = usb_get_intfdata(intf); struct cdc_mbim_state *info = (void *)&dev->data; struct cdc_ncm_ctx *ctx = info->ctx; if (!ctx) goto error; /* * Both usbnet_suspend() and subdriver->suspend() MUST return 0 * in system sleep context, otherwise, the resume callback has * to recover device from previous suspend failure. */ ret = usbnet_suspend(intf, message); if (ret < 0) goto error; if (intf == ctx->control && info->subdriver && info->subdriver->suspend) ret = info->subdriver->suspend(intf, message); if (ret < 0) usbnet_resume(intf); error: return ret; } static int cdc_mbim_resume(struct usb_interface *intf) { int ret = 0; struct usbnet *dev = usb_get_intfdata(intf); struct cdc_mbim_state *info = (void *)&dev->data; struct cdc_ncm_ctx *ctx = info->ctx; bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume); if (callsub) ret = info->subdriver->resume(intf); if (ret < 0) goto err; ret = usbnet_resume(intf); if (ret < 0 && callsub) info->subdriver->suspend(intf, PMSG_SUSPEND); err: return ret; } static const struct driver_info cdc_mbim_info = { .description = "CDC MBIM", .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN, .bind = cdc_mbim_bind, .unbind = cdc_mbim_unbind, .manage_power = cdc_mbim_manage_power, .rx_fixup = cdc_mbim_rx_fixup, .tx_fixup = cdc_mbim_tx_fixup, }; /* MBIM and NCM devices should not need a ZLP after NTBs with * dwNtbOutMaxSize length. Nevertheless, a number of devices from * different vendor IDs will fail unless we send ZLPs, forcing us * to make this the default. * * This default may cause a performance penalty for spec conforming * devices wanting to take advantage of optimizations possible without * ZLPs. A whitelist is added in an attempt to avoid this for devices * known to conform to the MBIM specification. * * All known devices supporting NCM compatibility mode are also * conforming to the NCM and MBIM specifications. For this reason, the * NCM subclass entry is also in the ZLP whitelist. */ static const struct driver_info cdc_mbim_info_zlp = { .description = "CDC MBIM", .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP, .bind = cdc_mbim_bind, .unbind = cdc_mbim_unbind, .manage_power = cdc_mbim_manage_power, .rx_fixup = cdc_mbim_rx_fixup, .tx_fixup = cdc_mbim_tx_fixup, }; static const struct usb_device_id mbim_devs[] = { /* This duplicate NCM entry is intentional. MBIM devices can * be disguised as NCM by default, and this is necessary to * allow us to bind the correct driver_info to such devices. * * bind() will sort out this for us, selecting the correct * entry and reject the other */ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE), .driver_info = (unsigned long)&cdc_mbim_info, }, /* ZLP conformance whitelist: All Ericsson MBIM devices */ { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE), .driver_info = (unsigned long)&cdc_mbim_info, }, /* default entry */ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE), .driver_info = (unsigned long)&cdc_mbim_info_zlp, }, { }, }; MODULE_DEVICE_TABLE(usb, mbim_devs); static struct usb_driver cdc_mbim_driver = { .name = "cdc_mbim", .id_table = mbim_devs, .probe = usbnet_probe, .disconnect = usbnet_disconnect, .suspend = cdc_mbim_suspend, .resume = cdc_mbim_resume, .reset_resume = cdc_mbim_resume, .supports_autosuspend = 1, .disable_hub_initiated_lpm = 1, }; module_usb_driver(cdc_mbim_driver); MODULE_AUTHOR("Greg Suarez "); MODULE_AUTHOR("Bjørn Mork "); MODULE_DESCRIPTION("USB CDC MBIM host driver"); MODULE_LICENSE("GPL");