xref: /linux/drivers/net/usb/cdc_mbim.c (revision bdd1a21b52557ea8f61d0a5dc2f77151b576eb70)
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      = dev_get_tstats64,
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 						 WWAN_PORT_MBIM,
172 						 cdc_mbim_wdm_manage_power);
173 	if (IS_ERR(subdriver)) {
174 		ret = PTR_ERR(subdriver);
175 		cdc_ncm_unbind(dev, intf);
176 		goto err;
177 	}
178 
179 	/* can't let usbnet use the interrupt endpoint */
180 	dev->status = NULL;
181 	info->subdriver = subdriver;
182 
183 	/* MBIM cannot do ARP */
184 	dev->net->flags |= IFF_NOARP;
185 
186 	/* no need to put the VLAN tci in the packet headers */
187 	dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
188 
189 	/* monitor VLAN additions and removals */
190 	dev->net->netdev_ops = &cdc_mbim_netdev_ops;
191 err:
192 	return ret;
193 }
194 
195 static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
196 {
197 	struct cdc_mbim_state *info = (void *)&dev->data;
198 	struct cdc_ncm_ctx *ctx = info->ctx;
199 
200 	/* disconnect subdriver from control interface */
201 	if (info->subdriver && info->subdriver->disconnect)
202 		info->subdriver->disconnect(ctx->control);
203 	info->subdriver = NULL;
204 
205 	/* let NCM unbind clean up both control and data interface */
206 	cdc_ncm_unbind(dev, intf);
207 }
208 
209 /* verify that the ethernet protocol is IPv4 or IPv6 */
210 static bool is_ip_proto(__be16 proto)
211 {
212 	switch (proto) {
213 	case htons(ETH_P_IP):
214 	case htons(ETH_P_IPV6):
215 		return true;
216 	}
217 	return false;
218 }
219 
220 static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
221 {
222 	struct sk_buff *skb_out;
223 	struct cdc_mbim_state *info = (void *)&dev->data;
224 	struct cdc_ncm_ctx *ctx = info->ctx;
225 	__le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
226 	u16 tci = 0;
227 	bool is_ip;
228 	u8 *c;
229 
230 	if (!ctx)
231 		goto error;
232 
233 	if (skb) {
234 		if (skb->len <= ETH_HLEN)
235 			goto error;
236 
237 		/* Some applications using e.g. packet sockets will
238 		 * bypass the VLAN acceleration and create tagged
239 		 * ethernet frames directly.  We primarily look for
240 		 * the accelerated out-of-band tag, but fall back if
241 		 * required
242 		 */
243 		skb_reset_mac_header(skb);
244 		if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
245 		    __vlan_get_tag(skb, &tci) == 0) {
246 			is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
247 			skb_pull(skb, VLAN_ETH_HLEN);
248 		} else {
249 			is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
250 			skb_pull(skb, ETH_HLEN);
251 		}
252 
253 		/* Is IP session <0> tagged too? */
254 		if (info->flags & FLAG_IPS0_VLAN) {
255 			/* drop all untagged packets */
256 			if (!tci)
257 				goto error;
258 			/* map MBIM_IPS0_VID to IPS<0> */
259 			if (tci == MBIM_IPS0_VID)
260 				tci = 0;
261 		}
262 
263 		/* mapping VLANs to MBIM sessions:
264 		 *   no tag     => IPS session <0> if !FLAG_IPS0_VLAN
265 		 *   1 - 255    => IPS session <vlanid>
266 		 *   256 - 511  => DSS session <vlanid - 256>
267 		 *   512 - 4093 => unsupported, drop
268 		 *   4094       => IPS session <0> if FLAG_IPS0_VLAN
269 		 */
270 
271 		switch (tci & 0x0f00) {
272 		case 0x0000: /* VLAN ID 0 - 255 */
273 			if (!is_ip)
274 				goto error;
275 			c = (u8 *)&sign;
276 			c[3] = tci;
277 			break;
278 		case 0x0100: /* VLAN ID 256 - 511 */
279 			if (is_ip)
280 				goto error;
281 			sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
282 			c = (u8 *)&sign;
283 			c[3] = tci;
284 			break;
285 		default:
286 			netif_err(dev, tx_err, dev->net,
287 				  "unsupported tci=0x%04x\n", tci);
288 			goto error;
289 		}
290 	}
291 
292 	spin_lock_bh(&ctx->mtx);
293 	skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
294 	spin_unlock_bh(&ctx->mtx);
295 	return skb_out;
296 
297 error:
298 	if (skb)
299 		dev_kfree_skb_any(skb);
300 
301 	return NULL;
302 }
303 
304 /* Some devices are known to send Neighbor Solicitation messages and
305  * require Neighbor Advertisement replies.  The IPv6 core will not
306  * respond since IFF_NOARP is set, so we must handle them ourselves.
307  */
308 static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
309 {
310 	struct ipv6hdr *iph = (void *)buf;
311 	struct nd_msg *msg = (void *)(iph + 1);
312 	struct net_device *netdev;
313 	struct inet6_dev *in6_dev;
314 	bool is_router;
315 
316 	/* we'll only respond to requests from unicast addresses to
317 	 * our solicited node addresses.
318 	 */
319 	if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
320 	    !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
321 		return;
322 
323 	/* need to send the NA on the VLAN dev, if any */
324 	rcu_read_lock();
325 	if (tci) {
326 		netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
327 						  tci);
328 		if (!netdev) {
329 			rcu_read_unlock();
330 			return;
331 		}
332 	} else {
333 		netdev = dev->net;
334 	}
335 	dev_hold(netdev);
336 	rcu_read_unlock();
337 
338 	in6_dev = in6_dev_get(netdev);
339 	if (!in6_dev)
340 		goto out;
341 	is_router = !!in6_dev->cnf.forwarding;
342 	in6_dev_put(in6_dev);
343 
344 	/* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
345 	ipv6_stub->ndisc_send_na(netdev, &iph->saddr, &msg->target,
346 				 is_router /* router */,
347 				 true /* solicited */,
348 				 false /* override */,
349 				 true /* inc_opt */);
350 out:
351 	dev_put(netdev);
352 }
353 
354 static bool is_neigh_solicit(u8 *buf, size_t len)
355 {
356 	struct ipv6hdr *iph = (void *)buf;
357 	struct nd_msg *msg = (void *)(iph + 1);
358 
359 	return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
360 		iph->nexthdr == IPPROTO_ICMPV6 &&
361 		msg->icmph.icmp6_code == 0 &&
362 		msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
363 }
364 
365 
366 static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
367 {
368 	__be16 proto = htons(ETH_P_802_3);
369 	struct sk_buff *skb = NULL;
370 
371 	if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
372 		if (len < sizeof(struct iphdr))
373 			goto err;
374 
375 		switch (*buf & 0xf0) {
376 		case 0x40:
377 			proto = htons(ETH_P_IP);
378 			break;
379 		case 0x60:
380 			if (is_neigh_solicit(buf, len))
381 				do_neigh_solicit(dev, buf, tci);
382 			proto = htons(ETH_P_IPV6);
383 			break;
384 		default:
385 			goto err;
386 		}
387 	}
388 
389 	skb = netdev_alloc_skb_ip_align(dev->net,  len + ETH_HLEN);
390 	if (!skb)
391 		goto err;
392 
393 	/* add an ethernet header */
394 	skb_put(skb, ETH_HLEN);
395 	skb_reset_mac_header(skb);
396 	eth_hdr(skb)->h_proto = proto;
397 	eth_zero_addr(eth_hdr(skb)->h_source);
398 	memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
399 
400 	/* add datagram */
401 	skb_put_data(skb, buf, len);
402 
403 	/* map MBIM session to VLAN */
404 	if (tci)
405 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
406 err:
407 	return skb;
408 }
409 
410 static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
411 {
412 	struct sk_buff *skb;
413 	struct cdc_mbim_state *info = (void *)&dev->data;
414 	struct cdc_ncm_ctx *ctx = info->ctx;
415 	int len;
416 	int nframes;
417 	int x;
418 	int offset;
419 	struct usb_cdc_ncm_ndp16 *ndp16;
420 	struct usb_cdc_ncm_dpe16 *dpe16;
421 	int ndpoffset;
422 	int loopcount = 50; /* arbitrary max preventing infinite loop */
423 	u32 payload = 0;
424 	u8 *c;
425 	u16 tci;
426 
427 	ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
428 	if (ndpoffset < 0)
429 		goto error;
430 
431 next_ndp:
432 	nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
433 	if (nframes < 0)
434 		goto error;
435 
436 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
437 
438 	switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
439 	case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
440 		c = (u8 *)&ndp16->dwSignature;
441 		tci = c[3];
442 		/* tag IPS<0> packets too if MBIM_IPS0_VID exists */
443 		if (!tci && info->flags & FLAG_IPS0_VLAN)
444 			tci = MBIM_IPS0_VID;
445 		break;
446 	case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
447 		c = (u8 *)&ndp16->dwSignature;
448 		tci = c[3] + 256;
449 		break;
450 	default:
451 		netif_dbg(dev, rx_err, dev->net,
452 			  "unsupported NDP signature <0x%08x>\n",
453 			  le32_to_cpu(ndp16->dwSignature));
454 		goto err_ndp;
455 
456 	}
457 
458 	dpe16 = ndp16->dpe16;
459 	for (x = 0; x < nframes; x++, dpe16++) {
460 		offset = le16_to_cpu(dpe16->wDatagramIndex);
461 		len = le16_to_cpu(dpe16->wDatagramLength);
462 
463 		/*
464 		 * CDC NCM ch. 3.7
465 		 * All entries after first NULL entry are to be ignored
466 		 */
467 		if ((offset == 0) || (len == 0)) {
468 			if (!x)
469 				goto err_ndp; /* empty NTB */
470 			break;
471 		}
472 
473 		/* sanity checking */
474 		if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
475 			netif_dbg(dev, rx_err, dev->net,
476 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
477 				  x, offset, len, skb_in);
478 			if (!x)
479 				goto err_ndp;
480 			break;
481 		} else {
482 			skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
483 			if (!skb)
484 				goto error;
485 			usbnet_skb_return(dev, skb);
486 			payload += len;	/* count payload bytes in this NTB */
487 		}
488 	}
489 err_ndp:
490 	/* are there more NDPs to process? */
491 	ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
492 	if (ndpoffset && loopcount--)
493 		goto next_ndp;
494 
495 	/* update stats */
496 	ctx->rx_overhead += skb_in->len - payload;
497 	ctx->rx_ntbs++;
498 
499 	return 1;
500 error:
501 	return 0;
502 }
503 
504 static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
505 {
506 	int ret = -ENODEV;
507 	struct usbnet *dev = usb_get_intfdata(intf);
508 	struct cdc_mbim_state *info = (void *)&dev->data;
509 	struct cdc_ncm_ctx *ctx = info->ctx;
510 
511 	if (!ctx)
512 		goto error;
513 
514 	/*
515 	 * Both usbnet_suspend() and subdriver->suspend() MUST return 0
516 	 * in system sleep context, otherwise, the resume callback has
517 	 * to recover device from previous suspend failure.
518 	 */
519 	ret = usbnet_suspend(intf, message);
520 	if (ret < 0)
521 		goto error;
522 
523 	if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
524 		ret = info->subdriver->suspend(intf, message);
525 	if (ret < 0)
526 		usbnet_resume(intf);
527 
528 error:
529 	return ret;
530 }
531 
532 static int cdc_mbim_resume(struct usb_interface *intf)
533 {
534 	int  ret = 0;
535 	struct usbnet *dev = usb_get_intfdata(intf);
536 	struct cdc_mbim_state *info = (void *)&dev->data;
537 	struct cdc_ncm_ctx *ctx = info->ctx;
538 	bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
539 
540 	if (callsub)
541 		ret = info->subdriver->resume(intf);
542 	if (ret < 0)
543 		goto err;
544 	ret = usbnet_resume(intf);
545 	if (ret < 0 && callsub)
546 		info->subdriver->suspend(intf, PMSG_SUSPEND);
547 err:
548 	return ret;
549 }
550 
551 static const struct driver_info cdc_mbim_info = {
552 	.description = "CDC MBIM",
553 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
554 	.bind = cdc_mbim_bind,
555 	.unbind = cdc_mbim_unbind,
556 	.manage_power = cdc_mbim_manage_power,
557 	.rx_fixup = cdc_mbim_rx_fixup,
558 	.tx_fixup = cdc_mbim_tx_fixup,
559 };
560 
561 /* MBIM and NCM devices should not need a ZLP after NTBs with
562  * dwNtbOutMaxSize length. Nevertheless, a number of devices from
563  * different vendor IDs will fail unless we send ZLPs, forcing us
564  * to make this the default.
565  *
566  * This default may cause a performance penalty for spec conforming
567  * devices wanting to take advantage of optimizations possible without
568  * ZLPs.  A whitelist is added in an attempt to avoid this for devices
569  * known to conform to the MBIM specification.
570  *
571  * All known devices supporting NCM compatibility mode are also
572  * conforming to the NCM and MBIM specifications. For this reason, the
573  * NCM subclass entry is also in the ZLP whitelist.
574  */
575 static const struct driver_info cdc_mbim_info_zlp = {
576 	.description = "CDC MBIM",
577 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
578 	.bind = cdc_mbim_bind,
579 	.unbind = cdc_mbim_unbind,
580 	.manage_power = cdc_mbim_manage_power,
581 	.rx_fixup = cdc_mbim_rx_fixup,
582 	.tx_fixup = cdc_mbim_tx_fixup,
583 };
584 
585 /* The spefication explicitly allows NDPs to be placed anywhere in the
586  * frame, but some devices fail unless the NDP is placed after the IP
587  * packets.  Using the CDC_NCM_FLAG_NDP_TO_END flags to force this
588  * behaviour.
589  *
590  * Note: The current implementation of this feature restricts each NTB
591  * to a single NDP, implying that multiplexed sessions cannot share an
592  * NTB. This might affect performance for multiplexed sessions.
593  */
594 static const struct driver_info cdc_mbim_info_ndp_to_end = {
595 	.description = "CDC MBIM",
596 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
597 	.bind = cdc_mbim_bind,
598 	.unbind = cdc_mbim_unbind,
599 	.manage_power = cdc_mbim_manage_power,
600 	.rx_fixup = cdc_mbim_rx_fixup,
601 	.tx_fixup = cdc_mbim_tx_fixup,
602 	.data = CDC_NCM_FLAG_NDP_TO_END,
603 };
604 
605 /* Some modems (e.g. Telit LE922A6) do not work properly with altsetting
606  * toggle done in cdc_ncm_bind_common. CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
607  * flag is used to avoid this procedure.
608  */
609 static const struct driver_info cdc_mbim_info_avoid_altsetting_toggle = {
610 	.description = "CDC MBIM",
611 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
612 	.bind = cdc_mbim_bind,
613 	.unbind = cdc_mbim_unbind,
614 	.manage_power = cdc_mbim_manage_power,
615 	.rx_fixup = cdc_mbim_rx_fixup,
616 	.tx_fixup = cdc_mbim_tx_fixup,
617 	.data = CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE,
618 };
619 
620 static const struct usb_device_id mbim_devs[] = {
621 	/* This duplicate NCM entry is intentional. MBIM devices can
622 	 * be disguised as NCM by default, and this is necessary to
623 	 * allow us to bind the correct driver_info to such devices.
624 	 *
625 	 * bind() will sort out this for us, selecting the correct
626 	 * entry and reject the other
627 	 */
628 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
629 	  .driver_info = (unsigned long)&cdc_mbim_info,
630 	},
631 	/* ZLP conformance whitelist: All Ericsson MBIM devices */
632 	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
633 	  .driver_info = (unsigned long)&cdc_mbim_info,
634 	},
635 
636 	/* Some Huawei devices, ME906s-158 (12d1:15c1) and E3372
637 	 * (12d1:157d), are known to fail unless the NDP is placed
638 	 * after the IP packets.  Applying the quirk to all Huawei
639 	 * devices is broader than necessary, but harmless.
640 	 */
641 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
642 	  .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
643 	},
644 
645 	/* The HP lt4132 (03f0:a31d) is a rebranded Huawei ME906s-158,
646 	 * therefore it too requires the above "NDP to end" quirk.
647 	 */
648 	{ USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
649 	  .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
650 	},
651 
652 	/* Telit LE922A6 in MBIM composition */
653 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x1041, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
654 	  .driver_info = (unsigned long)&cdc_mbim_info_avoid_altsetting_toggle,
655 	},
656 
657 	/* default entry */
658 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
659 	  .driver_info = (unsigned long)&cdc_mbim_info_zlp,
660 	},
661 	{
662 	},
663 };
664 MODULE_DEVICE_TABLE(usb, mbim_devs);
665 
666 static struct usb_driver cdc_mbim_driver = {
667 	.name = "cdc_mbim",
668 	.id_table = mbim_devs,
669 	.probe = usbnet_probe,
670 	.disconnect = usbnet_disconnect,
671 	.suspend = cdc_mbim_suspend,
672 	.resume = cdc_mbim_resume,
673 	.reset_resume =	cdc_mbim_resume,
674 	.supports_autosuspend = 1,
675 	.disable_hub_initiated_lpm = 1,
676 };
677 module_usb_driver(cdc_mbim_driver);
678 
679 MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
680 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
681 MODULE_DESCRIPTION("USB CDC MBIM host driver");
682 MODULE_LICENSE("GPL");
683