xref: /openbmc/linux/drivers/net/usb/cdc_mbim.c (revision c4e78957)
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 #include <net/ndisc.h>
25 
26 /* alternative VLAN for IP session 0 if not untagged */
27 #define MBIM_IPS0_VID	4094
28 
29 /* driver specific data - must match cdc_ncm usage */
30 struct cdc_mbim_state {
31 	struct cdc_ncm_ctx *ctx;
32 	atomic_t pmcount;
33 	struct usb_driver *subdriver;
34 	unsigned long _unused;
35 	unsigned long flags;
36 };
37 
38 /* flags for the cdc_mbim_state.flags field */
39 enum cdc_mbim_flags {
40 	FLAG_IPS0_VLAN = 1 << 0,	/* IP session 0 is tagged  */
41 };
42 
43 /* using a counter to merge subdriver requests with our own into a combined state */
44 static int cdc_mbim_manage_power(struct usbnet *dev, int on)
45 {
46 	struct cdc_mbim_state *info = (void *)&dev->data;
47 	int rv = 0;
48 
49 	dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
50 
51 	if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
52 		/* need autopm_get/put here to ensure the usbcore sees the new value */
53 		rv = usb_autopm_get_interface(dev->intf);
54 		dev->intf->needs_remote_wakeup = on;
55 		if (!rv)
56 			usb_autopm_put_interface(dev->intf);
57 	}
58 	return 0;
59 }
60 
61 static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
62 {
63 	struct usbnet *dev = usb_get_intfdata(intf);
64 
65 	/* can be called while disconnecting */
66 	if (!dev)
67 		return 0;
68 
69 	return cdc_mbim_manage_power(dev, status);
70 }
71 
72 static int cdc_mbim_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
73 {
74 	struct usbnet *dev = netdev_priv(netdev);
75 	struct cdc_mbim_state *info = (void *)&dev->data;
76 
77 	/* creation of this VLAN is a request to tag IP session 0 */
78 	if (vid == MBIM_IPS0_VID)
79 		info->flags |= FLAG_IPS0_VLAN;
80 	else
81 		if (vid >= 512)	/* we don't map these to MBIM session */
82 			return -EINVAL;
83 	return 0;
84 }
85 
86 static int cdc_mbim_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
87 {
88 	struct usbnet *dev = netdev_priv(netdev);
89 	struct cdc_mbim_state *info = (void *)&dev->data;
90 
91 	/* this is a request for an untagged IP session 0 */
92 	if (vid == MBIM_IPS0_VID)
93 		info->flags &= ~FLAG_IPS0_VLAN;
94 	return 0;
95 }
96 
97 static const struct net_device_ops cdc_mbim_netdev_ops = {
98 	.ndo_open             = usbnet_open,
99 	.ndo_stop             = usbnet_stop,
100 	.ndo_start_xmit       = usbnet_start_xmit,
101 	.ndo_tx_timeout       = usbnet_tx_timeout,
102 	.ndo_get_stats64      = dev_get_tstats64,
103 	.ndo_change_mtu       = cdc_ncm_change_mtu,
104 	.ndo_set_mac_address  = eth_mac_addr,
105 	.ndo_validate_addr    = eth_validate_addr,
106 	.ndo_vlan_rx_add_vid  = cdc_mbim_rx_add_vid,
107 	.ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
108 };
109 
110 /* Change the control interface altsetting and update the .driver_info
111  * pointer if the matching entry after changing class codes points to
112  * a different struct
113  */
114 static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
115 {
116 	struct usb_driver *driver = to_usb_driver(intf->dev.driver);
117 	const struct usb_device_id *id;
118 	struct driver_info *info;
119 	int ret;
120 
121 	ret = usb_set_interface(dev->udev,
122 				intf->cur_altsetting->desc.bInterfaceNumber,
123 				alt);
124 	if (ret)
125 		return ret;
126 
127 	id = usb_match_id(intf, driver->id_table);
128 	if (!id)
129 		return -ENODEV;
130 
131 	info = (struct driver_info *)id->driver_info;
132 	if (info != dev->driver_info) {
133 		dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
134 			info->description);
135 		dev->driver_info = info;
136 	}
137 	return 0;
138 }
139 
140 static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
141 {
142 	struct cdc_ncm_ctx *ctx;
143 	struct usb_driver *subdriver = ERR_PTR(-ENODEV);
144 	int ret = -ENODEV;
145 	u8 data_altsetting = 1;
146 	struct cdc_mbim_state *info = (void *)&dev->data;
147 
148 	/* should we change control altsetting on a NCM/MBIM function? */
149 	if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
150 		data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
151 		ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
152 		if (ret)
153 			goto err;
154 		ret = -ENODEV;
155 	}
156 
157 	/* we will hit this for NCM/MBIM functions if prefer_mbim is false */
158 	if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
159 		goto err;
160 
161 	ret = cdc_ncm_bind_common(dev, intf, data_altsetting, dev->driver_info->data);
162 	if (ret)
163 		goto err;
164 
165 	ctx = info->ctx;
166 
167 	/* The MBIM descriptor and the status endpoint are required */
168 	if (ctx->mbim_desc && dev->status)
169 		subdriver = usb_cdc_wdm_register(ctx->control,
170 						 &dev->status->desc,
171 						 le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
172 						 WWAN_PORT_MBIM,
173 						 cdc_mbim_wdm_manage_power);
174 	if (IS_ERR(subdriver)) {
175 		ret = PTR_ERR(subdriver);
176 		cdc_ncm_unbind(dev, intf);
177 		goto err;
178 	}
179 
180 	/* can't let usbnet use the interrupt endpoint */
181 	dev->status = NULL;
182 	info->subdriver = subdriver;
183 
184 	/* MBIM cannot do ARP */
185 	dev->net->flags |= IFF_NOARP;
186 
187 	/* no need to put the VLAN tci in the packet headers */
188 	dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
189 
190 	/* monitor VLAN additions and removals */
191 	dev->net->netdev_ops = &cdc_mbim_netdev_ops;
192 err:
193 	return ret;
194 }
195 
196 static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
197 {
198 	struct cdc_mbim_state *info = (void *)&dev->data;
199 	struct cdc_ncm_ctx *ctx = info->ctx;
200 
201 	/* disconnect subdriver from control interface */
202 	if (info->subdriver && info->subdriver->disconnect)
203 		info->subdriver->disconnect(ctx->control);
204 	info->subdriver = NULL;
205 
206 	/* let NCM unbind clean up both control and data interface */
207 	cdc_ncm_unbind(dev, intf);
208 }
209 
210 /* verify that the ethernet protocol is IPv4 or IPv6 */
211 static bool is_ip_proto(__be16 proto)
212 {
213 	switch (proto) {
214 	case htons(ETH_P_IP):
215 	case htons(ETH_P_IPV6):
216 		return true;
217 	}
218 	return false;
219 }
220 
221 static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
222 {
223 	struct sk_buff *skb_out;
224 	struct cdc_mbim_state *info = (void *)&dev->data;
225 	struct cdc_ncm_ctx *ctx = info->ctx;
226 	__le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
227 	u16 tci = 0;
228 	bool is_ip;
229 	u8 *c;
230 
231 	if (!ctx)
232 		goto error;
233 
234 	if (skb) {
235 		if (skb->len <= ETH_HLEN)
236 			goto error;
237 
238 		/* Some applications using e.g. packet sockets will
239 		 * bypass the VLAN acceleration and create tagged
240 		 * ethernet frames directly.  We primarily look for
241 		 * the accelerated out-of-band tag, but fall back if
242 		 * required
243 		 */
244 		skb_reset_mac_header(skb);
245 		if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
246 		    __vlan_get_tag(skb, &tci) == 0) {
247 			is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
248 			skb_pull(skb, VLAN_ETH_HLEN);
249 		} else {
250 			is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
251 			skb_pull(skb, ETH_HLEN);
252 		}
253 
254 		/* Is IP session <0> tagged too? */
255 		if (info->flags & FLAG_IPS0_VLAN) {
256 			/* drop all untagged packets */
257 			if (!tci)
258 				goto error;
259 			/* map MBIM_IPS0_VID to IPS<0> */
260 			if (tci == MBIM_IPS0_VID)
261 				tci = 0;
262 		}
263 
264 		/* mapping VLANs to MBIM sessions:
265 		 *   no tag     => IPS session <0> if !FLAG_IPS0_VLAN
266 		 *   1 - 255    => IPS session <vlanid>
267 		 *   256 - 511  => DSS session <vlanid - 256>
268 		 *   512 - 4093 => unsupported, drop
269 		 *   4094       => IPS session <0> if FLAG_IPS0_VLAN
270 		 */
271 
272 		switch (tci & 0x0f00) {
273 		case 0x0000: /* VLAN ID 0 - 255 */
274 			if (!is_ip)
275 				goto error;
276 			c = (u8 *)&sign;
277 			c[3] = tci;
278 			break;
279 		case 0x0100: /* VLAN ID 256 - 511 */
280 			if (is_ip)
281 				goto error;
282 			sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
283 			c = (u8 *)&sign;
284 			c[3] = tci;
285 			break;
286 		default:
287 			netif_err(dev, tx_err, dev->net,
288 				  "unsupported tci=0x%04x\n", tci);
289 			goto error;
290 		}
291 	}
292 
293 	spin_lock_bh(&ctx->mtx);
294 	skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
295 	spin_unlock_bh(&ctx->mtx);
296 	return skb_out;
297 
298 error:
299 	if (skb)
300 		dev_kfree_skb_any(skb);
301 
302 	return NULL;
303 }
304 
305 /* Some devices are known to send Neighbor Solicitation messages and
306  * require Neighbor Advertisement replies.  The IPv6 core will not
307  * respond since IFF_NOARP is set, so we must handle them ourselves.
308  */
309 static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
310 {
311 	struct ipv6hdr *iph = (void *)buf;
312 	struct nd_msg *msg = (void *)(iph + 1);
313 	struct net_device *netdev;
314 	struct inet6_dev *in6_dev;
315 	bool is_router;
316 
317 	/* we'll only respond to requests from unicast addresses to
318 	 * our solicited node addresses.
319 	 */
320 	if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
321 	    !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
322 		return;
323 
324 	/* need to send the NA on the VLAN dev, if any */
325 	rcu_read_lock();
326 	if (tci) {
327 		netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
328 						  tci);
329 		if (!netdev) {
330 			rcu_read_unlock();
331 			return;
332 		}
333 	} else {
334 		netdev = dev->net;
335 	}
336 	dev_hold(netdev);
337 	rcu_read_unlock();
338 
339 	in6_dev = in6_dev_get(netdev);
340 	if (!in6_dev)
341 		goto out;
342 	is_router = !!in6_dev->cnf.forwarding;
343 	in6_dev_put(in6_dev);
344 
345 	/* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
346 	ipv6_stub->ndisc_send_na(netdev, &iph->saddr, &msg->target,
347 				 is_router /* router */,
348 				 true /* solicited */,
349 				 false /* override */,
350 				 true /* inc_opt */);
351 out:
352 	dev_put(netdev);
353 }
354 
355 static bool is_neigh_solicit(u8 *buf, size_t len)
356 {
357 	struct ipv6hdr *iph = (void *)buf;
358 	struct nd_msg *msg = (void *)(iph + 1);
359 
360 	return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
361 		iph->nexthdr == IPPROTO_ICMPV6 &&
362 		msg->icmph.icmp6_code == 0 &&
363 		msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
364 }
365 
366 
367 static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
368 {
369 	__be16 proto = htons(ETH_P_802_3);
370 	struct sk_buff *skb = NULL;
371 
372 	if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
373 		if (len < sizeof(struct iphdr))
374 			goto err;
375 
376 		switch (*buf & 0xf0) {
377 		case 0x40:
378 			proto = htons(ETH_P_IP);
379 			break;
380 		case 0x60:
381 			if (is_neigh_solicit(buf, len))
382 				do_neigh_solicit(dev, buf, tci);
383 			proto = htons(ETH_P_IPV6);
384 			break;
385 		default:
386 			goto err;
387 		}
388 	}
389 
390 	skb = netdev_alloc_skb_ip_align(dev->net,  len + ETH_HLEN);
391 	if (!skb)
392 		goto err;
393 
394 	/* add an ethernet header */
395 	skb_put(skb, ETH_HLEN);
396 	skb_reset_mac_header(skb);
397 	eth_hdr(skb)->h_proto = proto;
398 	eth_zero_addr(eth_hdr(skb)->h_source);
399 	memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
400 
401 	/* add datagram */
402 	skb_put_data(skb, buf, len);
403 
404 	/* map MBIM session to VLAN */
405 	if (tci)
406 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
407 err:
408 	return skb;
409 }
410 
411 static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
412 {
413 	struct sk_buff *skb;
414 	struct cdc_mbim_state *info = (void *)&dev->data;
415 	struct cdc_ncm_ctx *ctx = info->ctx;
416 	int len;
417 	int nframes;
418 	int x;
419 	int offset;
420 	struct usb_cdc_ncm_ndp16 *ndp16;
421 	struct usb_cdc_ncm_dpe16 *dpe16;
422 	int ndpoffset;
423 	int loopcount = 50; /* arbitrary max preventing infinite loop */
424 	u32 payload = 0;
425 	u8 *c;
426 	u16 tci;
427 
428 	ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
429 	if (ndpoffset < 0)
430 		goto error;
431 
432 next_ndp:
433 	nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
434 	if (nframes < 0)
435 		goto error;
436 
437 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
438 
439 	switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
440 	case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
441 		c = (u8 *)&ndp16->dwSignature;
442 		tci = c[3];
443 		/* tag IPS<0> packets too if MBIM_IPS0_VID exists */
444 		if (!tci && info->flags & FLAG_IPS0_VLAN)
445 			tci = MBIM_IPS0_VID;
446 		break;
447 	case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
448 		c = (u8 *)&ndp16->dwSignature;
449 		tci = c[3] + 256;
450 		break;
451 	default:
452 		netif_dbg(dev, rx_err, dev->net,
453 			  "unsupported NDP signature <0x%08x>\n",
454 			  le32_to_cpu(ndp16->dwSignature));
455 		goto err_ndp;
456 
457 	}
458 
459 	dpe16 = ndp16->dpe16;
460 	for (x = 0; x < nframes; x++, dpe16++) {
461 		offset = le16_to_cpu(dpe16->wDatagramIndex);
462 		len = le16_to_cpu(dpe16->wDatagramLength);
463 
464 		/*
465 		 * CDC NCM ch. 3.7
466 		 * All entries after first NULL entry are to be ignored
467 		 */
468 		if ((offset == 0) || (len == 0)) {
469 			if (!x)
470 				goto err_ndp; /* empty NTB */
471 			break;
472 		}
473 
474 		/* sanity checking */
475 		if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
476 			netif_dbg(dev, rx_err, dev->net,
477 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
478 				  x, offset, len, skb_in);
479 			if (!x)
480 				goto err_ndp;
481 			break;
482 		} else {
483 			skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
484 			if (!skb)
485 				goto error;
486 			usbnet_skb_return(dev, skb);
487 			payload += len;	/* count payload bytes in this NTB */
488 		}
489 	}
490 err_ndp:
491 	/* are there more NDPs to process? */
492 	ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
493 	if (ndpoffset && loopcount--)
494 		goto next_ndp;
495 
496 	/* update stats */
497 	ctx->rx_overhead += skb_in->len - payload;
498 	ctx->rx_ntbs++;
499 
500 	return 1;
501 error:
502 	return 0;
503 }
504 
505 static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
506 {
507 	int ret = -ENODEV;
508 	struct usbnet *dev = usb_get_intfdata(intf);
509 	struct cdc_mbim_state *info = (void *)&dev->data;
510 	struct cdc_ncm_ctx *ctx = info->ctx;
511 
512 	if (!ctx)
513 		goto error;
514 
515 	/*
516 	 * Both usbnet_suspend() and subdriver->suspend() MUST return 0
517 	 * in system sleep context, otherwise, the resume callback has
518 	 * to recover device from previous suspend failure.
519 	 */
520 	ret = usbnet_suspend(intf, message);
521 	if (ret < 0)
522 		goto error;
523 
524 	if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
525 		ret = info->subdriver->suspend(intf, message);
526 	if (ret < 0)
527 		usbnet_resume(intf);
528 
529 error:
530 	return ret;
531 }
532 
533 static int cdc_mbim_resume(struct usb_interface *intf)
534 {
535 	int  ret = 0;
536 	struct usbnet *dev = usb_get_intfdata(intf);
537 	struct cdc_mbim_state *info = (void *)&dev->data;
538 	struct cdc_ncm_ctx *ctx = info->ctx;
539 	bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
540 
541 	if (callsub)
542 		ret = info->subdriver->resume(intf);
543 	if (ret < 0)
544 		goto err;
545 	ret = usbnet_resume(intf);
546 	if (ret < 0 && callsub)
547 		info->subdriver->suspend(intf, PMSG_SUSPEND);
548 err:
549 	return ret;
550 }
551 
552 static const struct driver_info cdc_mbim_info = {
553 	.description = "CDC MBIM",
554 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
555 	.bind = cdc_mbim_bind,
556 	.unbind = cdc_mbim_unbind,
557 	.manage_power = cdc_mbim_manage_power,
558 	.rx_fixup = cdc_mbim_rx_fixup,
559 	.tx_fixup = cdc_mbim_tx_fixup,
560 };
561 
562 /* MBIM and NCM devices should not need a ZLP after NTBs with
563  * dwNtbOutMaxSize length. Nevertheless, a number of devices from
564  * different vendor IDs will fail unless we send ZLPs, forcing us
565  * to make this the default.
566  *
567  * This default may cause a performance penalty for spec conforming
568  * devices wanting to take advantage of optimizations possible without
569  * ZLPs.  A whitelist is added in an attempt to avoid this for devices
570  * known to conform to the MBIM specification.
571  *
572  * All known devices supporting NCM compatibility mode are also
573  * conforming to the NCM and MBIM specifications. For this reason, the
574  * NCM subclass entry is also in the ZLP whitelist.
575  */
576 static const struct driver_info cdc_mbim_info_zlp = {
577 	.description = "CDC MBIM",
578 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
579 	.bind = cdc_mbim_bind,
580 	.unbind = cdc_mbim_unbind,
581 	.manage_power = cdc_mbim_manage_power,
582 	.rx_fixup = cdc_mbim_rx_fixup,
583 	.tx_fixup = cdc_mbim_tx_fixup,
584 };
585 
586 /* The spefication explicitly allows NDPs to be placed anywhere in the
587  * frame, but some devices fail unless the NDP is placed after the IP
588  * packets.  Using the CDC_NCM_FLAG_NDP_TO_END flags to force this
589  * behaviour.
590  *
591  * Note: The current implementation of this feature restricts each NTB
592  * to a single NDP, implying that multiplexed sessions cannot share an
593  * NTB. This might affect performance for multiplexed sessions.
594  */
595 static const struct driver_info cdc_mbim_info_ndp_to_end = {
596 	.description = "CDC MBIM",
597 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
598 	.bind = cdc_mbim_bind,
599 	.unbind = cdc_mbim_unbind,
600 	.manage_power = cdc_mbim_manage_power,
601 	.rx_fixup = cdc_mbim_rx_fixup,
602 	.tx_fixup = cdc_mbim_tx_fixup,
603 	.data = CDC_NCM_FLAG_NDP_TO_END,
604 };
605 
606 /* Some modems (e.g. Telit LE922A6) do not work properly with altsetting
607  * toggle done in cdc_ncm_bind_common. CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
608  * flag is used to avoid this procedure.
609  */
610 static const struct driver_info cdc_mbim_info_avoid_altsetting_toggle = {
611 	.description = "CDC MBIM",
612 	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
613 	.bind = cdc_mbim_bind,
614 	.unbind = cdc_mbim_unbind,
615 	.manage_power = cdc_mbim_manage_power,
616 	.rx_fixup = cdc_mbim_rx_fixup,
617 	.tx_fixup = cdc_mbim_tx_fixup,
618 	.data = CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE,
619 };
620 
621 static const struct usb_device_id mbim_devs[] = {
622 	/* This duplicate NCM entry is intentional. MBIM devices can
623 	 * be disguised as NCM by default, and this is necessary to
624 	 * allow us to bind the correct driver_info to such devices.
625 	 *
626 	 * bind() will sort out this for us, selecting the correct
627 	 * entry and reject the other
628 	 */
629 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
630 	  .driver_info = (unsigned long)&cdc_mbim_info,
631 	},
632 	/* ZLP conformance whitelist: All Ericsson MBIM devices */
633 	{ USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
634 	  .driver_info = (unsigned long)&cdc_mbim_info,
635 	},
636 
637 	/* Some Huawei devices, ME906s-158 (12d1:15c1) and E3372
638 	 * (12d1:157d), are known to fail unless the NDP is placed
639 	 * after the IP packets.  Applying the quirk to all Huawei
640 	 * devices is broader than necessary, but harmless.
641 	 */
642 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
643 	  .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
644 	},
645 
646 	/* The HP lt4132 (03f0:a31d) is a rebranded Huawei ME906s-158,
647 	 * therefore it too requires the above "NDP to end" quirk.
648 	 */
649 	{ USB_DEVICE_AND_INTERFACE_INFO(0x03f0, 0xa31d, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
650 	  .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
651 	},
652 
653 	/* Telit LE922A6 in MBIM composition */
654 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x1041, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
655 	  .driver_info = (unsigned long)&cdc_mbim_info_avoid_altsetting_toggle,
656 	},
657 
658 	/* Telit LN920 */
659 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x1061, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
660 	  .driver_info = (unsigned long)&cdc_mbim_info_avoid_altsetting_toggle,
661 	},
662 
663 	/* Telit FN990 */
664 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x1071, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
665 	  .driver_info = (unsigned long)&cdc_mbim_info_avoid_altsetting_toggle,
666 	},
667 
668 	/* default entry */
669 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
670 	  .driver_info = (unsigned long)&cdc_mbim_info_zlp,
671 	},
672 	{
673 	},
674 };
675 MODULE_DEVICE_TABLE(usb, mbim_devs);
676 
677 static struct usb_driver cdc_mbim_driver = {
678 	.name = "cdc_mbim",
679 	.id_table = mbim_devs,
680 	.probe = usbnet_probe,
681 	.disconnect = usbnet_disconnect,
682 	.suspend = cdc_mbim_suspend,
683 	.resume = cdc_mbim_resume,
684 	.reset_resume =	cdc_mbim_resume,
685 	.supports_autosuspend = 1,
686 	.disable_hub_initiated_lpm = 1,
687 };
688 module_usb_driver(cdc_mbim_driver);
689 
690 MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
691 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
692 MODULE_DESCRIPTION("USB CDC MBIM host driver");
693 MODULE_LICENSE("GPL");
694