[deliverable/linux.git] / drivers / net / usb / cdc_mbim.c

/*
 * Copyright (c) 2012  Smith Micro Software, Inc.
 * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
 *
 * 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 <linux/module.h>
#include <linux/netdevice.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/ip.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc-wdm.h>
#include <linux/usb/cdc_ncm.h>
#include <net/ipv6.h>
#include <net/addrconf.h>

/* 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);
}


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;
	u8 *c;

	if (!ctx)
		goto error;

	if (skb) {
		if (skb->len <= ETH_HLEN)
			goto error;

		/* mapping VLANs to MBIM sessions:
		 *   no tag     => IPS session <0>
		 *   1 - 255    => IPS session <vlanid>
		 *   256 - 511  => DSS session <vlanid - 256>
		 *   512 - 4095 => unsupported, drop
		 */
		vlan_get_tag(skb, &tci);

		switch (tci & 0x0f00) {
		case 0x0000: /* VLAN ID 0 - 255 */
			/* verify that datagram is IPv4 or IPv6 */
			skb_reset_mac_header(skb);
			switch (eth_hdr(skb)->h_proto) {
			case htons(ETH_P_IP):
			case htons(ETH_P_IPV6):
				break;
			default:
				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;
		}
		skb_pull(skb, ETH_HLEN);
	}

	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 */
	if (tci)
		netdev = __vlan_find_dev_deep(dev->net, htons(ETH_P_8021Q),
					      tci);
	else
		netdev = dev->net;
	if (!netdev)
		return;

	in6_dev = in6_dev_get(netdev);
	if (!in6_dev)
		return;
	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 */);
}

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 <gsuarez@smithmicro.com>");
MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
MODULE_DESCRIPTION("USB CDC MBIM host driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
9bf211a3 GS	1	/*
	2	* Copyright (c) 2012 Smith Micro Software, Inc.
	3	* Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
	4	*
	5	* This driver is based on and reuse most of cdc_ncm, which is
	6	* Copyright (C) ST-Ericsson 2010-2012
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* version 2 as published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/module.h>
	14	#include <linux/netdevice.h>
	15	#include <linux/ethtool.h>
a82c7ce5	16	#include <linux/if_vlan.h>
9bf211a3 GS	17	#include <linux/ip.h>
	18	#include <linux/mii.h>
	19	#include <linux/usb.h>
	20	#include <linux/usb/cdc.h>
	21	#include <linux/usb/usbnet.h>
	22	#include <linux/usb/cdc-wdm.h>
	23	#include <linux/usb/cdc_ncm.h>
5b8f15f7 BM	24	#include <net/ipv6.h>
5b8f15f7 BM	25	#include <net/addrconf.h>
9bf211a3 GS	26
	27	/* driver specific data - must match cdc_ncm usage */
	28	struct cdc_mbim_state {
	29	struct cdc_ncm_ctx *ctx;
	30	atomic_t pmcount;
	31	struct usb_driver *subdriver;
	32	struct usb_interface *control;
	33	struct usb_interface *data;
	34	};
	35
	36	/* using a counter to merge subdriver requests with our own into a combined state */
	37	static int cdc_mbim_manage_power(struct usbnet *dev, int on)
	38	{
	39	struct cdc_mbim_state info = (void )&dev->data;
	40	int rv = 0;
	41
	42	dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
	43
	44	if ((on && atomic_add_return(1, &info->pmcount) == 1) \|\| (!on && atomic_dec_and_test(&info->pmcount))) {
	45	/* need autopm_get/put here to ensure the usbcore sees the new value */
	46	rv = usb_autopm_get_interface(dev->intf);
9bf211a3	47	dev->intf->needs_remote_wakeup = on;
04d948a9 BM	48	if (!rv)
04d948a9 BM	49	usb_autopm_put_interface(dev->intf);
9bf211a3	50	}
04d948a9	51	return 0;
9bf211a3 GS	52	}
	53
	54	static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
	55	{
	56	struct usbnet *dev = usb_get_intfdata(intf);
	57
	58	/* can be called while disconnecting */
	59	if (!dev)
	60	return 0;
	61
	62	return cdc_mbim_manage_power(dev, status);
	63	}
	64
	65
	66	static int cdc_mbim_bind(struct usbnet dev, struct usb_interface intf)
	67	{
	68	struct cdc_ncm_ctx *ctx;
	69	struct usb_driver *subdriver = ERR_PTR(-ENODEV);
	70	int ret = -ENODEV;
1e8bbe6c	71	u8 data_altsetting = cdc_ncm_select_altsetting(dev, intf);
9bf211a3 GS	72	struct cdc_mbim_state info = (void )&dev->data;
9bf211a3 GS	73
9bf211a3 GS	74	/* Probably NCM, defer for cdc_ncm_bind */
	75	if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
	76	goto err;
	77
	78	ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
	79	if (ret)
	80	goto err;
	81
	82	ctx = info->ctx;
	83
	84	/* The MBIM descriptor and the status endpoint are required */
	85	if (ctx->mbim_desc && dev->status)
	86	subdriver = usb_cdc_wdm_register(ctx->control,
	87	&dev->status->desc,
	88	le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
	89	cdc_mbim_wdm_manage_power);
	90	if (IS_ERR(subdriver)) {
	91	ret = PTR_ERR(subdriver);
	92	cdc_ncm_unbind(dev, intf);
	93	goto err;
	94	}
	95
	96	/* can't let usbnet use the interrupt endpoint */
	97	dev->status = NULL;
	98	info->subdriver = subdriver;
	99
	100	/* MBIM cannot do ARP */
	101	dev->net->flags \|= IFF_NOARP;
a82c7ce5 BM	102
a82c7ce5 BM	103	/* no need to put the VLAN tci in the packet headers */
f646968f	104	dev->net->features \|= NETIF_F_HW_VLAN_CTAG_TX;
9bf211a3 GS	105	err:
	106	return ret;
	107	}
	108
	109	static void cdc_mbim_unbind(struct usbnet dev, struct usb_interface intf)
	110	{
	111	struct cdc_mbim_state info = (void )&dev->data;
	112	struct cdc_ncm_ctx *ctx = info->ctx;
	113
	114	/* disconnect subdriver from control interface */
	115	if (info->subdriver && info->subdriver->disconnect)
	116	info->subdriver->disconnect(ctx->control);
	117	info->subdriver = NULL;
	118
	119	/* let NCM unbind clean up both control and data interface */
	120	cdc_ncm_unbind(dev, intf);
	121	}
	122
	123
	124	static struct sk_buff cdc_mbim_tx_fixup(struct usbnet dev, struct sk_buff *skb, gfp_t flags)
	125	{
	126	struct sk_buff *skb_out;
	127	struct cdc_mbim_state info = (void )&dev->data;
	128	struct cdc_ncm_ctx *ctx = info->ctx;
a82c7ce5 BM	129	__le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
	130	u16 tci = 0;
	131	u8 *c;
9bf211a3 GS	132
	133	if (!ctx)
	134	goto error;
	135
	136	if (skb) {
32b161aa	137	if (skb->len <= ETH_HLEN)
9bf211a3 GS	138	goto error;
9bf211a3 GS	139
a82c7ce5 BM	140	/* mapping VLANs to MBIM sessions:
	141	* no tag => IPS session <0>
	142	* 1 - 255 => IPS session <vlanid>
9f651cac BM	143	* 256 - 511 => DSS session <vlanid - 256>
9f651cac BM	144	* 512 - 4095 => unsupported, drop
a82c7ce5 BM	145	*/
	146	vlan_get_tag(skb, &tci);
	147
	148	switch (tci & 0x0f00) {
	149	case 0x0000: /* VLAN ID 0 - 255 */
9f651cac BM	150	/* verify that datagram is IPv4 or IPv6 */
	151	skb_reset_mac_header(skb);
	152	switch (eth_hdr(skb)->h_proto) {
	153	case htons(ETH_P_IP):
	154	case htons(ETH_P_IPV6):
	155	break;
	156	default:
	157	goto error;
	158	}
	159	c = (u8 *)&sign;
	160	c[3] = tci;
	161	break;
	162	case 0x0100: /* VLAN ID 256 - 511 */
	163	sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
a82c7ce5 BM	164	c = (u8 *)&sign;
	165	c[3] = tci;
	166	break;
	167	default:
	168	netif_err(dev, tx_err, dev->net,
	169	"unsupported tci=0x%04x\n", tci);
	170	goto error;
	171	}
9f651cac	172	skb_pull(skb, ETH_HLEN);
9bf211a3 GS	173	}
	174
	175	spin_lock_bh(&ctx->mtx);
bed6f762	176	skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
9bf211a3 GS	177	spin_unlock_bh(&ctx->mtx);
	178	return skb_out;
	179
	180	error:
	181	if (skb)
	182	dev_kfree_skb_any(skb);
	183
	184	return NULL;
	185	}
	186
5b8f15f7 BM	187	/* Some devices are known to send Neigbor Solicitation messages and
	188	* require Neigbor Advertisement replies. The IPv6 core will not
	189	* respond since IFF_NOARP is set, so we must handle them ourselves.
	190	*/
	191	static void do_neigh_solicit(struct usbnet dev, u8 buf, u16 tci)
	192	{
	193	struct ipv6hdr iph = (void )buf;
	194	struct nd_msg msg = (void )(iph + 1);
	195	struct net_device *netdev;
	196	struct inet6_dev *in6_dev;
	197	bool is_router;
	198
	199	/* we'll only respond to requests from unicast addresses to
	200	* our solicited node addresses.
	201	*/
	202	if (!ipv6_addr_is_solict_mult(&iph->daddr) \|\|
	203	!(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
	204	return;
	205
	206	/* need to send the NA on the VLAN dev, if any */
	207	if (tci)
	208	netdev = __vlan_find_dev_deep(dev->net, htons(ETH_P_8021Q),
	209	tci);
	210	else
	211	netdev = dev->net;
	212	if (!netdev)
	213	return;
	214
	215	in6_dev = in6_dev_get(netdev);
	216	if (!in6_dev)
	217	return;
	218	is_router = !!in6_dev->cnf.forwarding;
	219	in6_dev_put(in6_dev);
	220
	221	/* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
	222	ipv6_stub->ndisc_send_na(netdev, NULL, &iph->saddr, &msg->target,
	223	is_router /* router */,
	224	true /* solicited */,
	225	false /* override */,
	226	true /* inc_opt */);
	227	}
	228
	229	static bool is_neigh_solicit(u8 *buf, size_t len)
	230	{
	231	struct ipv6hdr iph = (void )buf;
	232	struct nd_msg msg = (void )(iph + 1);
	233
	234	return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
	235	iph->nexthdr == IPPROTO_ICMPV6 &&
	236	msg->icmph.icmp6_code == 0 &&
	237	msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
	238	}
	239
	240
a82c7ce5	241	static struct sk_buff cdc_mbim_process_dgram(struct usbnet dev, u8 *buf, size_t len, u16 tci)
9bf211a3	242	{
9f651cac	243	__be16 proto = htons(ETH_P_802_3);
9bf211a3 GS	244	struct sk_buff *skb = NULL;
9bf211a3 GS	245
9f651cac BM	246	if (tci < 256) { /* IPS session? */
	247	if (len < sizeof(struct iphdr))
	248	goto err;
a82c7ce5	249
9f651cac BM	250	switch (*buf & 0xf0) {
	251	case 0x40:
	252	proto = htons(ETH_P_IP);
	253	break;
	254	case 0x60:
5b8f15f7 BM	255	if (is_neigh_solicit(buf, len))
5b8f15f7 BM	256	do_neigh_solicit(dev, buf, tci);
9f651cac BM	257	proto = htons(ETH_P_IPV6);
	258	break;
	259	default:
	260	goto err;
	261	}
9bf211a3 GS	262	}
	263
	264	skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
	265	if (!skb)
	266	goto err;
	267
	268	/* add an ethernet header */
	269	skb_put(skb, ETH_HLEN);
	270	skb_reset_mac_header(skb);
	271	eth_hdr(skb)->h_proto = proto;
	272	memset(eth_hdr(skb)->h_source, 0, ETH_ALEN);
	273	memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
	274
	275	/* add datagram */
	276	memcpy(skb_put(skb, len), buf, len);
a82c7ce5 BM	277
	278	/* map MBIM session to VLAN */
	279	if (tci)
86a9bad3	280	vlan_put_tag(skb, htons(ETH_P_8021Q), tci);
9bf211a3 GS	281	err:
	282	return skb;
	283	}
	284
	285	static int cdc_mbim_rx_fixup(struct usbnet dev, struct sk_buff skb_in)
	286	{
	287	struct sk_buff *skb;
a82c7ce5 BM	288	struct cdc_mbim_state info = (void )&dev->data;
a82c7ce5 BM	289	struct cdc_ncm_ctx *ctx = info->ctx;
9bf211a3 GS	290	int len;
	291	int nframes;
	292	int x;
	293	int offset;
	294	struct usb_cdc_ncm_ndp16 *ndp16;
	295	struct usb_cdc_ncm_dpe16 *dpe16;
	296	int ndpoffset;
	297	int loopcount = 50; /* arbitrary max preventing infinite loop */
a82c7ce5 BM	298	u8 *c;
a82c7ce5 BM	299	u16 tci;
9bf211a3 GS	300
	301	ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
	302	if (ndpoffset < 0)
	303	goto error;
	304
	305	next_ndp:
	306	nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
	307	if (nframes < 0)
	308	goto error;
	309
	310	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
	311
a82c7ce5	312	switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
9bf211a3	313	case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
a82c7ce5 BM	314	c = (u8 *)&ndp16->dwSignature;
a82c7ce5 BM	315	tci = c[3];
9bf211a3	316	break;
9f651cac BM	317	case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
	318	c = (u8 *)&ndp16->dwSignature;
	319	tci = c[3] + 256;
	320	break;
9bf211a3 GS	321	default:
	322	netif_dbg(dev, rx_err, dev->net,
	323	"unsupported NDP signature <0x%08x>\n",
	324	le32_to_cpu(ndp16->dwSignature));
	325	goto err_ndp;
	326
	327	}
	328
	329	dpe16 = ndp16->dpe16;
	330	for (x = 0; x < nframes; x++, dpe16++) {
	331	offset = le16_to_cpu(dpe16->wDatagramIndex);
	332	len = le16_to_cpu(dpe16->wDatagramLength);
	333
	334	/*
	335	* CDC NCM ch. 3.7
	336	* All entries after first NULL entry are to be ignored
	337	*/
	338	if ((offset == 0) \|\| (len == 0)) {
	339	if (!x)
	340	goto err_ndp; /* empty NTB */
	341	break;
	342	}
	343
	344	/* sanity checking */
a82c7ce5	345	if (((offset + len) > skb_in->len) \|\| (len > ctx->rx_max)) {
9bf211a3 GS	346	netif_dbg(dev, rx_err, dev->net,
	347	"invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
	348	x, offset, len, skb_in);
	349	if (!x)
	350	goto err_ndp;
	351	break;
	352	} else {
a82c7ce5	353	skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
9bf211a3 GS	354	if (!skb)
	355	goto error;
	356	usbnet_skb_return(dev, skb);
	357	}
	358	}
	359	err_ndp:
	360	/* are there more NDPs to process? */
	361	ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
	362	if (ndpoffset && loopcount--)
	363	goto next_ndp;
	364
	365	return 1;
	366	error:
	367	return 0;
	368	}
	369
	370	static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
	371	{
e62416e8	372	int ret = -ENODEV;
9bf211a3 GS	373	struct usbnet *dev = usb_get_intfdata(intf);
	374	struct cdc_mbim_state info = (void )&dev->data;
	375	struct cdc_ncm_ctx *ctx = info->ctx;
	376
e62416e8	377	if (!ctx)
9bf211a3	378	goto error;
9bf211a3	379
9a44312a ML	380	/*
	381	* Both usbnet_suspend() and subdriver->suspend() MUST return 0
	382	* in system sleep context, otherwise, the resume callback has
	383	* to recover device from previous suspend failure.
	384	*/
9bf211a3 GS	385	ret = usbnet_suspend(intf, message);
	386	if (ret < 0)
	387	goto error;
	388
	389	if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
	390	ret = info->subdriver->suspend(intf, message);
	391	if (ret < 0)
	392	usbnet_resume(intf);
	393
	394	error:
	395	return ret;
	396	}
	397
	398	static int cdc_mbim_resume(struct usb_interface *intf)
	399	{
	400	int ret = 0;
	401	struct usbnet *dev = usb_get_intfdata(intf);
	402	struct cdc_mbim_state info = (void )&dev->data;
	403	struct cdc_ncm_ctx *ctx = info->ctx;
	404	bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
	405
	406	if (callsub)
	407	ret = info->subdriver->resume(intf);
	408	if (ret < 0)
	409	goto err;
	410	ret = usbnet_resume(intf);
c37ac9b2	411	if (ret < 0 && callsub)
9bf211a3 GS	412	info->subdriver->suspend(intf, PMSG_SUSPEND);
	413	err:
	414	return ret;
	415	}
	416
	417	static const struct driver_info cdc_mbim_info = {
844e88f0 BM	418	.description = "CDC MBIM",
	419	.flags = FLAG_NO_SETINT \| FLAG_MULTI_PACKET \| FLAG_WWAN,
	420	.bind = cdc_mbim_bind,
	421	.unbind = cdc_mbim_unbind,
	422	.manage_power = cdc_mbim_manage_power,
	423	.rx_fixup = cdc_mbim_rx_fixup,
	424	.tx_fixup = cdc_mbim_tx_fixup,
	425	};
	426
	427	/* MBIM and NCM devices should not need a ZLP after NTBs with
c1a2e954 BM	428	* dwNtbOutMaxSize length. Nevertheless, a number of devices from
	429	* different vendor IDs will fail unless we send ZLPs, forcing us
	430	* to make this the default.
	431	*
	432	* This default may cause a performance penalty for spec conforming
	433	* devices wanting to take advantage of optimizations possible without
	434	* ZLPs. A whitelist is added in an attempt to avoid this for devices
	435	* known to conform to the MBIM specification.
	436	*
	437	* All known devices supporting NCM compatibility mode are also
	438	* conforming to the NCM and MBIM specifications. For this reason, the
	439	* NCM subclass entry is also in the ZLP whitelist.
844e88f0 BM	440	*/
844e88f0 BM	441	static const struct driver_info cdc_mbim_info_zlp = {
9bf211a3	442	.description = "CDC MBIM",
328d7b8a	443	.flags = FLAG_NO_SETINT \| FLAG_MULTI_PACKET \| FLAG_WWAN \| FLAG_SEND_ZLP,
9bf211a3 GS	444	.bind = cdc_mbim_bind,
	445	.unbind = cdc_mbim_unbind,
	446	.manage_power = cdc_mbim_manage_power,
	447	.rx_fixup = cdc_mbim_rx_fixup,
	448	.tx_fixup = cdc_mbim_tx_fixup,
	449	};
	450
	451	static const struct usb_device_id mbim_devs[] = {
	452	/* This duplicate NCM entry is intentional. MBIM devices can
	453	* be disguised as NCM by default, and this is necessary to
	454	* allow us to bind the correct driver_info to such devices.
	455	*
	456	* bind() will sort out this for us, selecting the correct
	457	* entry and reject the other
	458	*/
	459	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
	460	.driver_info = (unsigned long)&cdc_mbim_info,
	461	},
c1a2e954 BM	462	/* ZLP conformance whitelist: All Ericsson MBIM devices */
	463	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
	464	.driver_info = (unsigned long)&cdc_mbim_info,
03803a59	465	},
c1a2e954	466	/* default entry */
9bf211a3	467	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
c1a2e954	468	.driver_info = (unsigned long)&cdc_mbim_info_zlp,
9bf211a3 GS	469	},
	470	{
	471	},
	472	};
	473	MODULE_DEVICE_TABLE(usb, mbim_devs);
	474
	475	static struct usb_driver cdc_mbim_driver = {
	476	.name = "cdc_mbim",
	477	.id_table = mbim_devs,
	478	.probe = usbnet_probe,
	479	.disconnect = usbnet_disconnect,
	480	.suspend = cdc_mbim_suspend,
	481	.resume = cdc_mbim_resume,
	482	.reset_resume = cdc_mbim_resume,
	483	.supports_autosuspend = 1,
	484	.disable_hub_initiated_lpm = 1,
	485	};
	486	module_usb_driver(cdc_mbim_driver);
	487
	488	MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
	489	MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
	490	MODULE_DESCRIPTION("USB CDC MBIM host driver");
	491	MODULE_LICENSE("GPL");