xref: /openbmc/linux/drivers/net/usb/cdc_mbim.c (revision aad7ebb5)
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      = 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  */
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 						 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;
190 err:
191 	return ret;
192 }
193 
194 static 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 */
209 static 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 
219 static 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 
296 error:
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  */
307 static 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 */);
349 out:
350 	dev_put(netdev);
351 }
352 
353 static 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 
365 static 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);
405 err:
406 	return skb;
407 }
408 
409 static 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 
430 next_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 	}
488 err_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;
499 error:
500 	return 0;
501 }
502 
503 static 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 
527 error:
528 	return ret;
529 }
530 
531 static 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);
546 err:
547 	return ret;
548 }
549 
550 static 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  */
574 static 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  */
593 static 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  */
608 static 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 
619 static 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 };
663 MODULE_DEVICE_TABLE(usb, mbim_devs);
664 
665 static 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 };
676 module_usb_driver(cdc_mbim_driver);
677 
678 MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
679 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
680 MODULE_DESCRIPTION("USB CDC MBIM host driver");
681 MODULE_LICENSE("GPL");
682