xref: /linux/drivers/net/usb/cdc_ncm.c (revision b8e4b0529d59a3ccd0b25a31d3cfc8b0f3b34068)
1 /*
2  * cdc_ncm.c
3  *
4  * Copyright (C) ST-Ericsson 2010-2012
5  * Contact: Alexey Orishko <alexey.orishko@stericsson.com>
6  * Original author: Hans Petter Selasky <hans.petter.selasky@stericsson.com>
7  *
8  * USB Host Driver for Network Control Model (NCM)
9  * http://www.usb.org/developers/docs/devclass_docs/NCM10_012011.zip
10  *
11  * The NCM encoding, decoding and initialization logic
12  * derives from FreeBSD 8.x. if_cdce.c and if_cdcereg.h
13  *
14  * This software is available to you under a choice of one of two
15  * licenses. You may choose this file to be licensed under the terms
16  * of the GNU General Public License (GPL) Version 2 or the 2-clause
17  * BSD license listed below:
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #include <linux/module.h>
42 #include <linux/netdevice.h>
43 #include <linux/ctype.h>
44 #include <linux/etherdevice.h>
45 #include <linux/ethtool.h>
46 #include <linux/kstrtox.h>
47 #include <linux/workqueue.h>
48 #include <linux/mii.h>
49 #include <linux/crc32.h>
50 #include <linux/usb.h>
51 #include <linux/hrtimer.h>
52 #include <linux/atomic.h>
53 #include <linux/usb/usbnet.h>
54 #include <linux/usb/cdc.h>
55 #include <linux/usb/cdc_ncm.h>
56 
57 #if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
58 static bool prefer_mbim = true;
59 #else
60 static bool prefer_mbim;
61 #endif
62 module_param(prefer_mbim, bool, 0644);
63 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
64 
65 static void cdc_ncm_txpath_bh(struct tasklet_struct *t);
66 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
67 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
68 static struct usb_driver cdc_ncm_driver;
69 
70 struct cdc_ncm_stats {
71 	char stat_string[ETH_GSTRING_LEN];
72 	int sizeof_stat;
73 	int stat_offset;
74 };
75 
76 #define CDC_NCM_STAT(str, m) { \
77 		.stat_string = str, \
78 		.sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
79 		.stat_offset = offsetof(struct cdc_ncm_ctx, m) }
80 #define CDC_NCM_SIMPLE_STAT(m)	CDC_NCM_STAT(__stringify(m), m)
81 
82 static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
83 	CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
84 	CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
85 	CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
86 	CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
87 	CDC_NCM_SIMPLE_STAT(tx_overhead),
88 	CDC_NCM_SIMPLE_STAT(tx_ntbs),
89 	CDC_NCM_SIMPLE_STAT(rx_overhead),
90 	CDC_NCM_SIMPLE_STAT(rx_ntbs),
91 };
92 
93 #define CDC_NCM_LOW_MEM_MAX_CNT 10
94 
95 static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
96 {
97 	switch (sset) {
98 	case ETH_SS_STATS:
99 		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
100 	default:
101 		return -EOPNOTSUPP;
102 	}
103 }
104 
105 static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
106 				    struct ethtool_stats __always_unused *stats,
107 				    u64 *data)
108 {
109 	struct usbnet *dev = netdev_priv(netdev);
110 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
111 	int i;
112 	char *p = NULL;
113 
114 	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
115 		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
116 		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
117 	}
118 }
119 
120 static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
121 {
122 	u8 *p = data;
123 	int i;
124 
125 	switch (stringset) {
126 	case ETH_SS_STATS:
127 		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
128 			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
129 			p += ETH_GSTRING_LEN;
130 		}
131 	}
132 }
133 
134 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
135 
136 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
137 	.get_link		= usbnet_get_link,
138 	.nway_reset		= usbnet_nway_reset,
139 	.get_drvinfo		= usbnet_get_drvinfo,
140 	.get_msglevel		= usbnet_get_msglevel,
141 	.set_msglevel		= usbnet_set_msglevel,
142 	.get_ts_info		= ethtool_op_get_ts_info,
143 	.get_sset_count		= cdc_ncm_get_sset_count,
144 	.get_strings		= cdc_ncm_get_strings,
145 	.get_ethtool_stats	= cdc_ncm_get_ethtool_stats,
146 	.get_link_ksettings	= usbnet_get_link_ksettings_internal,
147 	.set_link_ksettings	= NULL,
148 };
149 
150 static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
151 {
152 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
153 	u32 val, max, min;
154 
155 	/* clamp new_rx to sane values */
156 	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
157 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
158 
159 	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
160 	if (max < min) {
161 		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
162 			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
163 		max = min;
164 	}
165 
166 	val = clamp_t(u32, new_rx, min, max);
167 	if (val != new_rx)
168 		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
169 
170 	return val;
171 }
172 
173 static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
174 {
175 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
176 	u32 val, max, min;
177 
178 	/* clamp new_tx to sane values */
179 	if (ctx->is_ndp16)
180 		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
181 	else
182 		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth32);
183 
184 	if (le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) == 0)
185 		max = CDC_NCM_NTB_MAX_SIZE_TX; /* dwNtbOutMaxSize not set */
186 	else
187 		max = clamp_t(u32, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize),
188 			      USB_CDC_NCM_NTB_MIN_OUT_SIZE,
189 			      CDC_NCM_NTB_MAX_SIZE_TX);
190 
191 	/* some devices set dwNtbOutMaxSize too low for the above default */
192 	min = min(min, max);
193 
194 	val = clamp_t(u32, new_tx, min, max);
195 	if (val != new_tx)
196 		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
197 
198 	return val;
199 }
200 
201 static ssize_t min_tx_pkt_show(struct device *d,
202 			       struct device_attribute *attr, char *buf)
203 {
204 	struct usbnet *dev = netdev_priv(to_net_dev(d));
205 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
206 
207 	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
208 }
209 
210 static ssize_t rx_max_show(struct device *d,
211 			   struct device_attribute *attr, char *buf)
212 {
213 	struct usbnet *dev = netdev_priv(to_net_dev(d));
214 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
215 
216 	return sprintf(buf, "%u\n", ctx->rx_max);
217 }
218 
219 static ssize_t tx_max_show(struct device *d,
220 			   struct device_attribute *attr, char *buf)
221 {
222 	struct usbnet *dev = netdev_priv(to_net_dev(d));
223 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
224 
225 	return sprintf(buf, "%u\n", ctx->tx_max);
226 }
227 
228 static ssize_t tx_timer_usecs_show(struct device *d,
229 				   struct device_attribute *attr, char *buf)
230 {
231 	struct usbnet *dev = netdev_priv(to_net_dev(d));
232 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
233 
234 	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
235 }
236 
237 static ssize_t min_tx_pkt_store(struct device *d,
238 				struct device_attribute *attr,
239 				const char *buf, size_t len)
240 {
241 	struct usbnet *dev = netdev_priv(to_net_dev(d));
242 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
243 	unsigned long val;
244 
245 	/* no need to restrict values - anything from 0 to infinity is OK */
246 	if (kstrtoul(buf, 0, &val))
247 		return -EINVAL;
248 
249 	ctx->min_tx_pkt = val;
250 	return len;
251 }
252 
253 static ssize_t rx_max_store(struct device *d,
254 			    struct device_attribute *attr,
255 			    const char *buf, size_t len)
256 {
257 	struct usbnet *dev = netdev_priv(to_net_dev(d));
258 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
259 	unsigned long val;
260 
261 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
262 		return -EINVAL;
263 
264 	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
265 	return len;
266 }
267 
268 static ssize_t tx_max_store(struct device *d,
269 			    struct device_attribute *attr,
270 			    const char *buf, size_t len)
271 {
272 	struct usbnet *dev = netdev_priv(to_net_dev(d));
273 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
274 	unsigned long val;
275 
276 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
277 		return -EINVAL;
278 
279 	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
280 	return len;
281 }
282 
283 static ssize_t tx_timer_usecs_store(struct device *d,
284 				    struct device_attribute *attr,
285 				    const char *buf, size_t len)
286 {
287 	struct usbnet *dev = netdev_priv(to_net_dev(d));
288 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
289 	ssize_t ret;
290 	unsigned long val;
291 
292 	ret = kstrtoul(buf, 0, &val);
293 	if (ret)
294 		return ret;
295 	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
296 		return -EINVAL;
297 
298 	spin_lock_bh(&ctx->mtx);
299 	ctx->timer_interval = val * NSEC_PER_USEC;
300 	if (!ctx->timer_interval)
301 		ctx->tx_timer_pending = 0;
302 	spin_unlock_bh(&ctx->mtx);
303 	return len;
304 }
305 
306 static DEVICE_ATTR_RW(min_tx_pkt);
307 static DEVICE_ATTR_RW(rx_max);
308 static DEVICE_ATTR_RW(tx_max);
309 static DEVICE_ATTR_RW(tx_timer_usecs);
310 
311 static ssize_t ndp_to_end_show(struct device *d, struct device_attribute *attr, char *buf)
312 {
313 	struct usbnet *dev = netdev_priv(to_net_dev(d));
314 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
315 
316 	return sprintf(buf, "%c\n", ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END ? 'Y' : 'N');
317 }
318 
319 static ssize_t ndp_to_end_store(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
320 {
321 	struct usbnet *dev = netdev_priv(to_net_dev(d));
322 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
323 	bool enable;
324 
325 	if (kstrtobool(buf, &enable))
326 		return -EINVAL;
327 
328 	/* no change? */
329 	if (enable == (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
330 		return len;
331 
332 	if (enable) {
333 		if (ctx->is_ndp16 && !ctx->delayed_ndp16) {
334 			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
335 			if (!ctx->delayed_ndp16)
336 				return -ENOMEM;
337 		}
338 		if (!ctx->is_ndp16 && !ctx->delayed_ndp32) {
339 			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
340 			if (!ctx->delayed_ndp32)
341 				return -ENOMEM;
342 		}
343 	}
344 
345 	/* flush pending data before changing flag */
346 	netif_tx_lock_bh(dev->net);
347 	usbnet_start_xmit(NULL, dev->net);
348 	spin_lock_bh(&ctx->mtx);
349 	if (enable)
350 		ctx->drvflags |= CDC_NCM_FLAG_NDP_TO_END;
351 	else
352 		ctx->drvflags &= ~CDC_NCM_FLAG_NDP_TO_END;
353 	spin_unlock_bh(&ctx->mtx);
354 	netif_tx_unlock_bh(dev->net);
355 
356 	return len;
357 }
358 static DEVICE_ATTR_RW(ndp_to_end);
359 
360 #define NCM_PARM_ATTR(name, format, tocpu)				\
361 static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
362 { \
363 	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
364 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
365 	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
366 } \
367 static DEVICE_ATTR(name, 0444, cdc_ncm_show_##name, NULL)
368 
369 NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
370 NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
371 NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
372 NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
373 NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
374 NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
375 NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
376 NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
377 NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
378 NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
379 
380 static struct attribute *cdc_ncm_sysfs_attrs[] = {
381 	&dev_attr_min_tx_pkt.attr,
382 	&dev_attr_ndp_to_end.attr,
383 	&dev_attr_rx_max.attr,
384 	&dev_attr_tx_max.attr,
385 	&dev_attr_tx_timer_usecs.attr,
386 	&dev_attr_bmNtbFormatsSupported.attr,
387 	&dev_attr_dwNtbInMaxSize.attr,
388 	&dev_attr_wNdpInDivisor.attr,
389 	&dev_attr_wNdpInPayloadRemainder.attr,
390 	&dev_attr_wNdpInAlignment.attr,
391 	&dev_attr_dwNtbOutMaxSize.attr,
392 	&dev_attr_wNdpOutDivisor.attr,
393 	&dev_attr_wNdpOutPayloadRemainder.attr,
394 	&dev_attr_wNdpOutAlignment.attr,
395 	&dev_attr_wNtbOutMaxDatagrams.attr,
396 	NULL,
397 };
398 
399 static const struct attribute_group cdc_ncm_sysfs_attr_group = {
400 	.name = "cdc_ncm",
401 	.attrs = cdc_ncm_sysfs_attrs,
402 };
403 
404 /* handle rx_max and tx_max changes */
405 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
406 {
407 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
408 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
409 	u32 val;
410 
411 	val = cdc_ncm_check_rx_max(dev, new_rx);
412 
413 	/* inform device about NTB input size changes */
414 	if (val != ctx->rx_max) {
415 		__le32 dwNtbInMaxSize = cpu_to_le32(val);
416 
417 		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
418 
419 		/* tell device to use new size */
420 		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
421 				     USB_TYPE_CLASS | USB_DIR_OUT
422 				     | USB_RECIP_INTERFACE,
423 				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
424 			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
425 		else
426 			ctx->rx_max = val;
427 	}
428 
429 	/* usbnet use these values for sizing rx queues */
430 	if (dev->rx_urb_size != ctx->rx_max) {
431 		dev->rx_urb_size = ctx->rx_max;
432 		if (netif_running(dev->net))
433 			usbnet_unlink_rx_urbs(dev);
434 	}
435 
436 	val = cdc_ncm_check_tx_max(dev, new_tx);
437 	if (val != ctx->tx_max)
438 		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
439 
440 	/* Adding a pad byte here if necessary simplifies the handling
441 	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
442 	 * the real skb max size.
443 	 *
444 	 * We cannot use dev->maxpacket here because this is called from
445 	 * .bind which is called before usbnet sets up dev->maxpacket
446 	 */
447 	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
448 	    val % usb_maxpacket(dev->udev, dev->out) == 0)
449 		val++;
450 
451 	/* we might need to flush any pending tx buffers if running */
452 	if (netif_running(dev->net) && val > ctx->tx_max) {
453 		netif_tx_lock_bh(dev->net);
454 		usbnet_start_xmit(NULL, dev->net);
455 		/* make sure tx_curr_skb is reallocated if it was empty */
456 		if (ctx->tx_curr_skb) {
457 			dev_kfree_skb_any(ctx->tx_curr_skb);
458 			ctx->tx_curr_skb = NULL;
459 		}
460 		ctx->tx_max = val;
461 		netif_tx_unlock_bh(dev->net);
462 	} else {
463 		ctx->tx_max = val;
464 	}
465 
466 	dev->hard_mtu = ctx->tx_max;
467 
468 	/* max qlen depend on hard_mtu and rx_urb_size */
469 	usbnet_update_max_qlen(dev);
470 
471 	/* never pad more than 3 full USB packets per transfer */
472 	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out),
473 				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
474 }
475 
476 /* helpers for NCM and MBIM differences */
477 static u8 cdc_ncm_flags(struct usbnet *dev)
478 {
479 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
480 
481 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
482 		return ctx->mbim_desc->bmNetworkCapabilities;
483 	if (ctx->func_desc)
484 		return ctx->func_desc->bmNetworkCapabilities;
485 	return 0;
486 }
487 
488 static int cdc_ncm_eth_hlen(struct usbnet *dev)
489 {
490 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
491 		return 0;
492 	return ETH_HLEN;
493 }
494 
495 static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
496 {
497 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
498 		return CDC_MBIM_MIN_DATAGRAM_SIZE;
499 	return CDC_NCM_MIN_DATAGRAM_SIZE;
500 }
501 
502 static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
503 {
504 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
505 
506 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
507 		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
508 	if (ctx->ether_desc)
509 		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
510 	return CDC_NCM_MAX_DATAGRAM_SIZE;
511 }
512 
513 /* initial one-time device setup.  MUST be called with the data interface
514  * in altsetting 0
515  */
516 static int cdc_ncm_init(struct usbnet *dev)
517 {
518 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
519 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
520 	int err;
521 
522 	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
523 			      USB_TYPE_CLASS | USB_DIR_IN
524 			      |USB_RECIP_INTERFACE,
525 			      0, iface_no, &ctx->ncm_parm,
526 			      sizeof(ctx->ncm_parm));
527 	if (err < 0) {
528 		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
529 		return err; /* GET_NTB_PARAMETERS is required */
530 	}
531 
532 	/* set CRC Mode */
533 	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
534 		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
535 		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
536 				       USB_TYPE_CLASS | USB_DIR_OUT
537 				       | USB_RECIP_INTERFACE,
538 				       USB_CDC_NCM_CRC_NOT_APPENDED,
539 				       iface_no, NULL, 0);
540 		if (err < 0)
541 			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
542 	}
543 
544 	/* use ndp16 by default */
545 	ctx->is_ndp16 = 1;
546 
547 	/* set NTB format, if both formats are supported.
548 	 *
549 	 * "The host shall only send this command while the NCM Data
550 	 *  Interface is in alternate setting 0."
551 	 */
552 	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
553 						USB_CDC_NCM_NTB32_SUPPORTED) {
554 		if (ctx->drvflags & CDC_NCM_FLAG_PREFER_NTB32) {
555 			ctx->is_ndp16 = 0;
556 			dev_dbg(&dev->intf->dev, "Setting NTB format to 32-bit\n");
557 			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
558 					       USB_TYPE_CLASS | USB_DIR_OUT
559 					       | USB_RECIP_INTERFACE,
560 					       USB_CDC_NCM_NTB32_FORMAT,
561 					       iface_no, NULL, 0);
562 		} else {
563 			ctx->is_ndp16 = 1;
564 			dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
565 			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
566 					       USB_TYPE_CLASS | USB_DIR_OUT
567 					       | USB_RECIP_INTERFACE,
568 					       USB_CDC_NCM_NTB16_FORMAT,
569 					       iface_no, NULL, 0);
570 		}
571 		if (err < 0) {
572 			ctx->is_ndp16 = 1;
573 			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
574 		}
575 	}
576 
577 	/* set initial device values */
578 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
579 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
580 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
581 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
582 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
583 	/* devices prior to NCM Errata shall set this field to zero */
584 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
585 
586 	dev_dbg(&dev->intf->dev,
587 		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
588 		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
589 		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
590 
591 	/* max count of tx datagrams */
592 	if ((ctx->tx_max_datagrams == 0) ||
593 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
594 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
595 
596 	/* set up maximum NDP size */
597 	if (ctx->is_ndp16)
598 		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
599 	else
600 		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp32) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe32);
601 
602 	/* initial coalescing timer interval */
603 	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
604 
605 	return 0;
606 }
607 
608 /* set a new max datagram size */
609 static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
610 {
611 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
612 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
613 	__le16 max_datagram_size;
614 	u16 mbim_mtu;
615 	int err;
616 
617 	/* set default based on descriptors */
618 	ctx->max_datagram_size = clamp_t(u32, new_size,
619 					 cdc_ncm_min_dgram_size(dev),
620 					 CDC_NCM_MAX_DATAGRAM_SIZE);
621 
622 	/* inform the device about the selected Max Datagram Size? */
623 	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
624 		goto out;
625 
626 	/* read current mtu value from device */
627 	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
628 			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
629 			      0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
630 	if (err != sizeof(max_datagram_size)) {
631 		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
632 		goto out;
633 	}
634 
635 	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
636 		goto out;
637 
638 	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
639 	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
640 			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
641 			       0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
642 	if (err < 0)
643 		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
644 
645 out:
646 	/* set MTU to max supported by the device if necessary */
647 	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
648 
649 	/* do not exceed operator preferred MTU */
650 	if (ctx->mbim_extended_desc) {
651 		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
652 		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
653 			dev->net->mtu = mbim_mtu;
654 	}
655 }
656 
657 static void cdc_ncm_fix_modulus(struct usbnet *dev)
658 {
659 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
660 	u32 val;
661 
662 	/*
663 	 * verify that the structure alignment is:
664 	 * - power of two
665 	 * - not greater than the maximum transmit length
666 	 * - not less than four bytes
667 	 */
668 	val = ctx->tx_ndp_modulus;
669 
670 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
671 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
672 		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
673 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
674 	}
675 
676 	/*
677 	 * verify that the payload alignment is:
678 	 * - power of two
679 	 * - not greater than the maximum transmit length
680 	 * - not less than four bytes
681 	 */
682 	val = ctx->tx_modulus;
683 
684 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
685 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
686 		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
687 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
688 	}
689 
690 	/* verify the payload remainder */
691 	if (ctx->tx_remainder >= ctx->tx_modulus) {
692 		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
693 		ctx->tx_remainder = 0;
694 	}
695 
696 	/* adjust TX-remainder according to NCM specification. */
697 	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
698 			     (ctx->tx_modulus - 1));
699 }
700 
701 static int cdc_ncm_setup(struct usbnet *dev)
702 {
703 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
704 	u32 def_rx, def_tx;
705 
706 	/* be conservative when selecting initial buffer size to
707 	 * increase the number of hosts this will work for
708 	 */
709 	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
710 		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
711 	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
712 		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
713 
714 	/* clamp rx_max and tx_max and inform device */
715 	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
716 
717 	/* sanitize the modulus and remainder values */
718 	cdc_ncm_fix_modulus(dev);
719 
720 	/* set max datagram size */
721 	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
722 	return 0;
723 }
724 
725 static void
726 cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
727 {
728 	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
729 	u8 ep;
730 
731 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
732 		e = intf->cur_altsetting->endpoint + ep;
733 
734 		/* ignore endpoints which cannot transfer data */
735 		if (!usb_endpoint_maxp(&e->desc))
736 			continue;
737 
738 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
739 		case USB_ENDPOINT_XFER_INT:
740 			if (usb_endpoint_dir_in(&e->desc)) {
741 				if (!dev->status)
742 					dev->status = e;
743 			}
744 			break;
745 
746 		case USB_ENDPOINT_XFER_BULK:
747 			if (usb_endpoint_dir_in(&e->desc)) {
748 				if (!in)
749 					in = e;
750 			} else {
751 				if (!out)
752 					out = e;
753 			}
754 			break;
755 
756 		default:
757 			break;
758 		}
759 	}
760 	if (in && !dev->in)
761 		dev->in = usb_rcvbulkpipe(dev->udev,
762 					  in->desc.bEndpointAddress &
763 					  USB_ENDPOINT_NUMBER_MASK);
764 	if (out && !dev->out)
765 		dev->out = usb_sndbulkpipe(dev->udev,
766 					   out->desc.bEndpointAddress &
767 					   USB_ENDPOINT_NUMBER_MASK);
768 }
769 
770 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
771 {
772 	if (ctx == NULL)
773 		return;
774 
775 	if (ctx->tx_rem_skb != NULL) {
776 		dev_kfree_skb_any(ctx->tx_rem_skb);
777 		ctx->tx_rem_skb = NULL;
778 	}
779 
780 	if (ctx->tx_curr_skb != NULL) {
781 		dev_kfree_skb_any(ctx->tx_curr_skb);
782 		ctx->tx_curr_skb = NULL;
783 	}
784 
785 	if (ctx->is_ndp16)
786 		kfree(ctx->delayed_ndp16);
787 	else
788 		kfree(ctx->delayed_ndp32);
789 
790 	kfree(ctx);
791 }
792 
793 /* we need to override the usbnet change_mtu ndo for two reasons:
794  *  - respect the negotiated maximum datagram size
795  *  - avoid unwanted changes to rx and tx buffers
796  */
797 int cdc_ncm_change_mtu(struct net_device *net, int new_mtu)
798 {
799 	struct usbnet *dev = netdev_priv(net);
800 
801 	WRITE_ONCE(net->mtu, new_mtu);
802 	cdc_ncm_set_dgram_size(dev, new_mtu + cdc_ncm_eth_hlen(dev));
803 
804 	return 0;
805 }
806 EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu);
807 
808 static const struct net_device_ops cdc_ncm_netdev_ops = {
809 	.ndo_open	     = usbnet_open,
810 	.ndo_stop	     = usbnet_stop,
811 	.ndo_start_xmit	     = usbnet_start_xmit,
812 	.ndo_tx_timeout	     = usbnet_tx_timeout,
813 	.ndo_set_rx_mode     = usbnet_set_rx_mode,
814 	.ndo_get_stats64     = dev_get_tstats64,
815 	.ndo_change_mtu	     = cdc_ncm_change_mtu,
816 	.ndo_set_mac_address = eth_mac_addr,
817 	.ndo_validate_addr   = eth_validate_addr,
818 };
819 
820 int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
821 {
822 	struct cdc_ncm_ctx *ctx;
823 	struct usb_driver *driver;
824 	u8 *buf;
825 	int len;
826 	int temp;
827 	u8 iface_no;
828 	struct usb_cdc_parsed_header hdr;
829 
830 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
831 	if (!ctx)
832 		return -ENOMEM;
833 
834 	ctx->dev = dev;
835 
836 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
837 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
838 	tasklet_setup(&ctx->bh, cdc_ncm_txpath_bh);
839 	atomic_set(&ctx->stop, 0);
840 	spin_lock_init(&ctx->mtx);
841 
842 	/* store ctx pointer in device data field */
843 	dev->data[0] = (unsigned long)ctx;
844 
845 	/* only the control interface can be successfully probed */
846 	ctx->control = intf;
847 
848 	/* get some pointers */
849 	driver = driver_of(intf);
850 	buf = intf->cur_altsetting->extra;
851 	len = intf->cur_altsetting->extralen;
852 
853 	/* parse through descriptors associated with control interface */
854 	cdc_parse_cdc_header(&hdr, intf, buf, len);
855 
856 	if (hdr.usb_cdc_union_desc)
857 		ctx->data = usb_ifnum_to_if(dev->udev,
858 					    hdr.usb_cdc_union_desc->bSlaveInterface0);
859 	ctx->ether_desc = hdr.usb_cdc_ether_desc;
860 	ctx->func_desc = hdr.usb_cdc_ncm_desc;
861 	ctx->mbim_desc = hdr.usb_cdc_mbim_desc;
862 	ctx->mbim_extended_desc = hdr.usb_cdc_mbim_extended_desc;
863 
864 	/* some buggy devices have an IAD but no CDC Union */
865 	if (!hdr.usb_cdc_union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
866 		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
867 		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
868 	}
869 
870 	/* check if we got everything */
871 	if (!ctx->data) {
872 		dev_err(&intf->dev, "CDC Union missing and no IAD found\n");
873 		goto error;
874 	}
875 	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
876 		if (!ctx->mbim_desc) {
877 			dev_err(&intf->dev, "MBIM functional descriptor missing\n");
878 			goto error;
879 		}
880 	} else {
881 		if (!ctx->ether_desc || !ctx->func_desc) {
882 			dev_err(&intf->dev, "NCM or ECM functional descriptors missing\n");
883 			goto error;
884 		}
885 	}
886 
887 	/* claim data interface, if different from control */
888 	if (ctx->data != ctx->control) {
889 		temp = usb_driver_claim_interface(driver, ctx->data, dev);
890 		if (temp) {
891 			dev_err(&intf->dev, "failed to claim data intf\n");
892 			goto error;
893 		}
894 	}
895 
896 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
897 
898 	/* Device-specific flags */
899 	ctx->drvflags = drvflags;
900 
901 	/* Reset data interface. Some devices will not reset properly
902 	 * unless they are configured first.  Toggle the altsetting to
903 	 * force a reset.
904 	 * Some other devices do not work properly with this procedure
905 	 * that can be avoided using quirk CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
906 	 */
907 	if (!(ctx->drvflags & CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE))
908 		usb_set_interface(dev->udev, iface_no, data_altsetting);
909 
910 	temp = usb_set_interface(dev->udev, iface_no, 0);
911 	if (temp) {
912 		dev_dbg(&intf->dev, "set interface failed\n");
913 		goto error2;
914 	}
915 
916 	/* initialize basic device settings */
917 	if (cdc_ncm_init(dev))
918 		goto error2;
919 
920 	/* Some firmwares need a pause here or they will silently fail
921 	 * to set up the interface properly.  This value was decided
922 	 * empirically on a Sierra Wireless MC7455 running 02.08.02.00
923 	 * firmware.
924 	 */
925 	usleep_range(10000, 20000);
926 
927 	/* configure data interface */
928 	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
929 	if (temp) {
930 		dev_dbg(&intf->dev, "set interface failed\n");
931 		goto error2;
932 	}
933 
934 	cdc_ncm_find_endpoints(dev, ctx->data);
935 	cdc_ncm_find_endpoints(dev, ctx->control);
936 	if (!dev->in || !dev->out ||
937 	    (!dev->status && dev->driver_info->flags & FLAG_LINK_INTR)) {
938 		dev_dbg(&intf->dev, "failed to collect endpoints\n");
939 		goto error2;
940 	}
941 
942 	usb_set_intfdata(ctx->control, dev);
943 
944 	if (ctx->ether_desc) {
945 		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
946 		if (temp) {
947 			dev_err(&intf->dev, "failed to get mac address\n");
948 			goto error2;
949 		}
950 		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
951 	}
952 
953 	/* finish setting up the device specific data */
954 	cdc_ncm_setup(dev);
955 
956 	/* Allocate the delayed NDP if needed. */
957 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
958 		if (ctx->is_ndp16) {
959 			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
960 			if (!ctx->delayed_ndp16)
961 				goto error2;
962 		} else {
963 			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
964 			if (!ctx->delayed_ndp32)
965 				goto error2;
966 		}
967 		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
968 	}
969 
970 	/* override ethtool_ops */
971 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
972 
973 	/* add our sysfs attrs */
974 	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
975 
976 	/* must handle MTU changes */
977 	dev->net->netdev_ops = &cdc_ncm_netdev_ops;
978 	dev->net->max_mtu = cdc_ncm_max_dgram_size(dev) - cdc_ncm_eth_hlen(dev);
979 
980 	return 0;
981 
982 error2:
983 	usb_set_intfdata(ctx->control, NULL);
984 	usb_set_intfdata(ctx->data, NULL);
985 	if (ctx->data != ctx->control)
986 		usb_driver_release_interface(driver, ctx->data);
987 error:
988 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
989 	dev->data[0] = 0;
990 	dev_info(&intf->dev, "bind() failure\n");
991 	return -ENODEV;
992 }
993 EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
994 
995 void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
996 {
997 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
998 	struct usb_driver *driver = driver_of(intf);
999 
1000 	if (ctx == NULL)
1001 		return;		/* no setup */
1002 
1003 	atomic_set(&ctx->stop, 1);
1004 
1005 	hrtimer_cancel(&ctx->tx_timer);
1006 
1007 	tasklet_kill(&ctx->bh);
1008 
1009 	/* handle devices with combined control and data interface */
1010 	if (ctx->control == ctx->data)
1011 		ctx->data = NULL;
1012 
1013 	/* disconnect master --> disconnect slave */
1014 	if (intf == ctx->control && ctx->data) {
1015 		usb_set_intfdata(ctx->data, NULL);
1016 		usb_driver_release_interface(driver, ctx->data);
1017 		ctx->data = NULL;
1018 
1019 	} else if (intf == ctx->data && ctx->control) {
1020 		usb_set_intfdata(ctx->control, NULL);
1021 		usb_driver_release_interface(driver, ctx->control);
1022 		ctx->control = NULL;
1023 	}
1024 
1025 	usb_set_intfdata(intf, NULL);
1026 	cdc_ncm_free(ctx);
1027 }
1028 EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
1029 
1030 /* Return the number of the MBIM control interface altsetting iff it
1031  * is preferred and available,
1032  */
1033 u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
1034 {
1035 	struct usb_host_interface *alt;
1036 
1037 	/* The MBIM spec defines a NCM compatible default altsetting,
1038 	 * which we may have matched:
1039 	 *
1040 	 *  "Functions that implement both NCM 1.0 and MBIM (an
1041 	 *   “NCM/MBIM function”) according to this recommendation
1042 	 *   shall provide two alternate settings for the
1043 	 *   Communication Interface.  Alternate setting 0, and the
1044 	 *   associated class and endpoint descriptors, shall be
1045 	 *   constructed according to the rules given for the
1046 	 *   Communication Interface in section 5 of [USBNCM10].
1047 	 *   Alternate setting 1, and the associated class and
1048 	 *   endpoint descriptors, shall be constructed according to
1049 	 *   the rules given in section 6 (USB Device Model) of this
1050 	 *   specification."
1051 	 */
1052 	if (intf->num_altsetting < 2)
1053 		return intf->cur_altsetting->desc.bAlternateSetting;
1054 
1055 	if (prefer_mbim) {
1056 		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
1057 		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
1058 			return CDC_NCM_COMM_ALTSETTING_MBIM;
1059 	}
1060 	return CDC_NCM_COMM_ALTSETTING_NCM;
1061 }
1062 EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
1063 
1064 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
1065 {
1066 	/* MBIM backwards compatible function? */
1067 	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
1068 		return -ENODEV;
1069 
1070 	/* The NCM data altsetting is fixed, so we hard-coded it.
1071 	 * Additionally, generic NCM devices are assumed to accept arbitrarily
1072 	 * placed NDP.
1073 	 */
1074 	return cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
1075 }
1076 
1077 static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
1078 {
1079 	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
1080 
1081 	if (skb->len + align > max)
1082 		align = max - skb->len;
1083 	if (align && skb_tailroom(skb) >= align)
1084 		skb_put_zero(skb, align);
1085 }
1086 
1087 /* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
1088  * allocating a new one within skb
1089  */
1090 static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1091 {
1092 	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1093 	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1094 	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1095 
1096 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1097 	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1098 	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1099 	*/
1100 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1101 		if (ctx->delayed_ndp16->dwSignature == sign)
1102 			return ctx->delayed_ndp16;
1103 
1104 		/* We can only push a single NDP to the end. Return
1105 		 * NULL to send what we've already got and queue this
1106 		 * skb for later.
1107 		 */
1108 		else if (ctx->delayed_ndp16->dwSignature)
1109 			return NULL;
1110 	}
1111 
1112 	/* follow the chain of NDPs, looking for a match */
1113 	while (ndpoffset) {
1114 		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1115 		if  (ndp16->dwSignature == sign)
1116 			return ndp16;
1117 		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1118 	}
1119 
1120 	/* align new NDP */
1121 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1122 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1123 
1124 	/* verify that there is room for the NDP and the datagram (reserve) */
1125 	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1126 		return NULL;
1127 
1128 	/* link to it */
1129 	if (ndp16)
1130 		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1131 	else
1132 		nth16->wNdpIndex = cpu_to_le16(skb->len);
1133 
1134 	/* push a new empty NDP */
1135 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1136 		ndp16 = skb_put_zero(skb, ctx->max_ndp_size);
1137 	else
1138 		ndp16 = ctx->delayed_ndp16;
1139 
1140 	ndp16->dwSignature = sign;
1141 	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1142 	return ndp16;
1143 }
1144 
1145 static struct usb_cdc_ncm_ndp32 *cdc_ncm_ndp32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1146 {
1147 	struct usb_cdc_ncm_ndp32 *ndp32 = NULL;
1148 	struct usb_cdc_ncm_nth32 *nth32 = (void *)skb->data;
1149 	size_t ndpoffset = le32_to_cpu(nth32->dwNdpIndex);
1150 
1151 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1152 	 * NTH32 header as we would normally do. NDP isn't written to the SKB yet, and
1153 	 * the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1154 	 */
1155 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1156 		if (ctx->delayed_ndp32->dwSignature == sign)
1157 			return ctx->delayed_ndp32;
1158 
1159 		/* We can only push a single NDP to the end. Return
1160 		 * NULL to send what we've already got and queue this
1161 		 * skb for later.
1162 		 */
1163 		else if (ctx->delayed_ndp32->dwSignature)
1164 			return NULL;
1165 	}
1166 
1167 	/* follow the chain of NDPs, looking for a match */
1168 	while (ndpoffset) {
1169 		ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb->data + ndpoffset);
1170 		if  (ndp32->dwSignature == sign)
1171 			return ndp32;
1172 		ndpoffset = le32_to_cpu(ndp32->dwNextNdpIndex);
1173 	}
1174 
1175 	/* align new NDP */
1176 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1177 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1178 
1179 	/* verify that there is room for the NDP and the datagram (reserve) */
1180 	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1181 		return NULL;
1182 
1183 	/* link to it */
1184 	if (ndp32)
1185 		ndp32->dwNextNdpIndex = cpu_to_le32(skb->len);
1186 	else
1187 		nth32->dwNdpIndex = cpu_to_le32(skb->len);
1188 
1189 	/* push a new empty NDP */
1190 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1191 		ndp32 = skb_put_zero(skb, ctx->max_ndp_size);
1192 	else
1193 		ndp32 = ctx->delayed_ndp32;
1194 
1195 	ndp32->dwSignature = sign;
1196 	ndp32->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp32) + sizeof(struct usb_cdc_ncm_dpe32));
1197 	return ndp32;
1198 }
1199 
1200 struct sk_buff *
1201 cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1202 {
1203 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1204 	union {
1205 		struct usb_cdc_ncm_nth16 *nth16;
1206 		struct usb_cdc_ncm_nth32 *nth32;
1207 	} nth;
1208 	union {
1209 		struct usb_cdc_ncm_ndp16 *ndp16;
1210 		struct usb_cdc_ncm_ndp32 *ndp32;
1211 	} ndp;
1212 	struct sk_buff *skb_out;
1213 	u16 n = 0, index, ndplen;
1214 	u8 ready2send = 0;
1215 	u32 delayed_ndp_size;
1216 	size_t padding_count;
1217 
1218 	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1219 	 * accordingly. Otherwise, we should check here.
1220 	 */
1221 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1222 		delayed_ndp_size = ctx->max_ndp_size +
1223 			max_t(u32,
1224 			      ctx->tx_ndp_modulus,
1225 			      ctx->tx_modulus + ctx->tx_remainder) - 1;
1226 	else
1227 		delayed_ndp_size = 0;
1228 
1229 	/* if there is a remaining skb, it gets priority */
1230 	if (skb != NULL) {
1231 		swap(skb, ctx->tx_rem_skb);
1232 		swap(sign, ctx->tx_rem_sign);
1233 	} else {
1234 		ready2send = 1;
1235 	}
1236 
1237 	/* check if we are resuming an OUT skb */
1238 	skb_out = ctx->tx_curr_skb;
1239 
1240 	/* allocate a new OUT skb */
1241 	if (!skb_out) {
1242 		if (ctx->tx_low_mem_val == 0) {
1243 			ctx->tx_curr_size = ctx->tx_max;
1244 			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1245 			/* If the memory allocation fails we will wait longer
1246 			 * each time before attempting another full size
1247 			 * allocation again to not overload the system
1248 			 * further.
1249 			 */
1250 			if (skb_out == NULL) {
1251 				/* If even the smallest allocation fails, abort. */
1252 				if (ctx->tx_curr_size == USB_CDC_NCM_NTB_MIN_OUT_SIZE)
1253 					goto alloc_failed;
1254 				ctx->tx_low_mem_max_cnt = min(ctx->tx_low_mem_max_cnt + 1,
1255 							      (unsigned)CDC_NCM_LOW_MEM_MAX_CNT);
1256 				ctx->tx_low_mem_val = ctx->tx_low_mem_max_cnt;
1257 			}
1258 		}
1259 		if (skb_out == NULL) {
1260 			/* See if a very small allocation is possible.
1261 			 * We will send this packet immediately and hope
1262 			 * that there is more memory available later.
1263 			 */
1264 			if (skb)
1265 				ctx->tx_curr_size = max(skb->len,
1266 					(u32)USB_CDC_NCM_NTB_MIN_OUT_SIZE);
1267 			else
1268 				ctx->tx_curr_size = USB_CDC_NCM_NTB_MIN_OUT_SIZE;
1269 			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1270 
1271 			/* No allocation possible so we will abort */
1272 			if (!skb_out)
1273 				goto alloc_failed;
1274 			ctx->tx_low_mem_val--;
1275 		}
1276 		if (ctx->is_ndp16) {
1277 			/* fill out the initial 16-bit NTB header */
1278 			nth.nth16 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth16));
1279 			nth.nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1280 			nth.nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1281 			nth.nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1282 		} else {
1283 			/* fill out the initial 32-bit NTB header */
1284 			nth.nth32 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth32));
1285 			nth.nth32->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH32_SIGN);
1286 			nth.nth32->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth32));
1287 			nth.nth32->wSequence = cpu_to_le16(ctx->tx_seq++);
1288 		}
1289 
1290 		/* count total number of frames in this NTB */
1291 		ctx->tx_curr_frame_num = 0;
1292 
1293 		/* recent payload counter for this skb_out */
1294 		ctx->tx_curr_frame_payload = 0;
1295 	}
1296 
1297 	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1298 		/* send any remaining skb first */
1299 		if (skb == NULL) {
1300 			skb = ctx->tx_rem_skb;
1301 			sign = ctx->tx_rem_sign;
1302 			ctx->tx_rem_skb = NULL;
1303 
1304 			/* check for end of skb */
1305 			if (skb == NULL)
1306 				break;
1307 		}
1308 
1309 		/* get the appropriate NDP for this skb */
1310 		if (ctx->is_ndp16)
1311 			ndp.ndp16 = cdc_ncm_ndp16(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1312 		else
1313 			ndp.ndp32 = cdc_ncm_ndp32(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1314 
1315 		/* align beginning of next frame */
1316 		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_curr_size);
1317 
1318 		/* check if we had enough room left for both NDP and frame */
1319 		if ((ctx->is_ndp16 && !ndp.ndp16) || (!ctx->is_ndp16 && !ndp.ndp32) ||
1320 		    skb_out->len + skb->len + delayed_ndp_size > ctx->tx_curr_size) {
1321 			if (n == 0) {
1322 				/* won't fit, MTU problem? */
1323 				dev_kfree_skb_any(skb);
1324 				skb = NULL;
1325 				dev->net->stats.tx_dropped++;
1326 			} else {
1327 				/* no room for skb - store for later */
1328 				if (ctx->tx_rem_skb != NULL) {
1329 					dev_kfree_skb_any(ctx->tx_rem_skb);
1330 					dev->net->stats.tx_dropped++;
1331 				}
1332 				ctx->tx_rem_skb = skb;
1333 				ctx->tx_rem_sign = sign;
1334 				skb = NULL;
1335 				ready2send = 1;
1336 				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1337 			}
1338 			break;
1339 		}
1340 
1341 		/* calculate frame number within this NDP */
1342 		if (ctx->is_ndp16) {
1343 			ndplen = le16_to_cpu(ndp.ndp16->wLength);
1344 			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1345 
1346 			/* OK, add this skb */
1347 			ndp.ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1348 			ndp.ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1349 			ndp.ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1350 		} else {
1351 			ndplen = le16_to_cpu(ndp.ndp32->wLength);
1352 			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp32)) / sizeof(struct usb_cdc_ncm_dpe32) - 1;
1353 
1354 			ndp.ndp32->dpe32[index].dwDatagramLength = cpu_to_le32(skb->len);
1355 			ndp.ndp32->dpe32[index].dwDatagramIndex = cpu_to_le32(skb_out->len);
1356 			ndp.ndp32->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe32));
1357 		}
1358 		skb_put_data(skb_out, skb->data, skb->len);
1359 		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1360 		dev_kfree_skb_any(skb);
1361 		skb = NULL;
1362 
1363 		/* send now if this NDP is full */
1364 		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1365 			ready2send = 1;
1366 			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1367 			break;
1368 		}
1369 	}
1370 
1371 	/* free up any dangling skb */
1372 	if (skb != NULL) {
1373 		dev_kfree_skb_any(skb);
1374 		skb = NULL;
1375 		dev->net->stats.tx_dropped++;
1376 	}
1377 
1378 	ctx->tx_curr_frame_num = n;
1379 
1380 	if (n == 0) {
1381 		/* wait for more frames */
1382 		/* push variables */
1383 		ctx->tx_curr_skb = skb_out;
1384 		goto exit_no_skb;
1385 
1386 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1387 		/* wait for more frames */
1388 		/* push variables */
1389 		ctx->tx_curr_skb = skb_out;
1390 		/* set the pending count */
1391 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1392 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1393 		goto exit_no_skb;
1394 
1395 	} else {
1396 		if (n == ctx->tx_max_datagrams)
1397 			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1398 		/* frame goes out */
1399 		/* variables will be reset at next call */
1400 	}
1401 
1402 	/* If requested, put NDP at end of frame. */
1403 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1404 		if (ctx->is_ndp16) {
1405 			nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1406 			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1407 			nth.nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1408 			skb_put_data(skb_out, ctx->delayed_ndp16, ctx->max_ndp_size);
1409 
1410 			/* Zero out delayed NDP - signature checking will naturally fail. */
1411 			ndp.ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1412 		} else {
1413 			nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1414 			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1415 			nth.nth32->dwNdpIndex = cpu_to_le32(skb_out->len);
1416 			skb_put_data(skb_out, ctx->delayed_ndp32, ctx->max_ndp_size);
1417 
1418 			ndp.ndp32 = memset(ctx->delayed_ndp32, 0, ctx->max_ndp_size);
1419 		}
1420 	}
1421 
1422 	/* If collected data size is less or equal ctx->min_tx_pkt
1423 	 * bytes, we send buffers as it is. If we get more data, it
1424 	 * would be more efficient for USB HS mobile device with DMA
1425 	 * engine to receive a full size NTB, than canceling DMA
1426 	 * transfer and receiving a short packet.
1427 	 *
1428 	 * This optimization support is pointless if we end up sending
1429 	 * a ZLP after full sized NTBs.
1430 	 */
1431 	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1432 	    skb_out->len > ctx->min_tx_pkt) {
1433 		padding_count = ctx->tx_curr_size - skb_out->len;
1434 		if (!WARN_ON(padding_count > ctx->tx_curr_size))
1435 			skb_put_zero(skb_out, padding_count);
1436 	} else if (skb_out->len < ctx->tx_curr_size &&
1437 		   (skb_out->len % dev->maxpacket) == 0) {
1438 		skb_put_u8(skb_out, 0);	/* force short packet */
1439 	}
1440 
1441 	/* set final frame length */
1442 	if (ctx->is_ndp16) {
1443 		nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1444 		nth.nth16->wBlockLength = cpu_to_le16(skb_out->len);
1445 	} else {
1446 		nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1447 		nth.nth32->dwBlockLength = cpu_to_le32(skb_out->len);
1448 	}
1449 
1450 	/* return skb */
1451 	ctx->tx_curr_skb = NULL;
1452 
1453 	/* keep private stats: framing overhead and number of NTBs */
1454 	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1455 	ctx->tx_ntbs++;
1456 
1457 	/* usbnet will count all the framing overhead by default.
1458 	 * Adjust the stats so that the tx_bytes counter show real
1459 	 * payload data instead.
1460 	 */
1461 	usbnet_set_skb_tx_stats(skb_out, n,
1462 				(long)ctx->tx_curr_frame_payload - skb_out->len);
1463 
1464 	return skb_out;
1465 
1466 alloc_failed:
1467 	if (skb) {
1468 		dev_kfree_skb_any(skb);
1469 		dev->net->stats.tx_dropped++;
1470 	}
1471 exit_no_skb:
1472 	/* Start timer, if there is a remaining non-empty skb */
1473 	if (ctx->tx_curr_skb != NULL && n > 0)
1474 		cdc_ncm_tx_timeout_start(ctx);
1475 	return NULL;
1476 }
1477 EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1478 
1479 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1480 {
1481 	/* start timer, if not already started */
1482 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1483 		hrtimer_start(&ctx->tx_timer,
1484 				ctx->timer_interval,
1485 				HRTIMER_MODE_REL);
1486 }
1487 
1488 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1489 {
1490 	struct cdc_ncm_ctx *ctx =
1491 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1492 
1493 	if (!atomic_read(&ctx->stop))
1494 		tasklet_schedule(&ctx->bh);
1495 	return HRTIMER_NORESTART;
1496 }
1497 
1498 static void cdc_ncm_txpath_bh(struct tasklet_struct *t)
1499 {
1500 	struct cdc_ncm_ctx *ctx = from_tasklet(ctx, t, bh);
1501 	struct usbnet *dev = ctx->dev;
1502 
1503 	spin_lock(&ctx->mtx);
1504 	if (ctx->tx_timer_pending != 0) {
1505 		ctx->tx_timer_pending--;
1506 		cdc_ncm_tx_timeout_start(ctx);
1507 		spin_unlock(&ctx->mtx);
1508 	} else if (dev->net != NULL) {
1509 		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1510 		spin_unlock(&ctx->mtx);
1511 		netif_tx_lock_bh(dev->net);
1512 		usbnet_start_xmit(NULL, dev->net);
1513 		netif_tx_unlock_bh(dev->net);
1514 	} else {
1515 		spin_unlock(&ctx->mtx);
1516 	}
1517 }
1518 
1519 struct sk_buff *
1520 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1521 {
1522 	struct sk_buff *skb_out;
1523 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1524 
1525 	/*
1526 	 * The Ethernet API we are using does not support transmitting
1527 	 * multiple Ethernet frames in a single call. This driver will
1528 	 * accumulate multiple Ethernet frames and send out a larger
1529 	 * USB frame when the USB buffer is full or when a single jiffies
1530 	 * timeout happens.
1531 	 */
1532 	if (ctx == NULL)
1533 		goto error;
1534 
1535 	spin_lock_bh(&ctx->mtx);
1536 
1537 	if (ctx->is_ndp16)
1538 		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1539 	else
1540 		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN));
1541 
1542 	spin_unlock_bh(&ctx->mtx);
1543 	return skb_out;
1544 
1545 error:
1546 	if (skb != NULL)
1547 		dev_kfree_skb_any(skb);
1548 
1549 	return NULL;
1550 }
1551 EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1552 
1553 /* verify NTB header and return offset of first NDP, or negative error */
1554 int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1555 {
1556 	struct usbnet *dev = netdev_priv(skb_in->dev);
1557 	struct usb_cdc_ncm_nth16 *nth16;
1558 	int len;
1559 	int ret = -EINVAL;
1560 
1561 	if (ctx == NULL)
1562 		goto error;
1563 
1564 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1565 					sizeof(struct usb_cdc_ncm_ndp16))) {
1566 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1567 		goto error;
1568 	}
1569 
1570 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1571 
1572 	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1573 		netif_dbg(dev, rx_err, dev->net,
1574 			  "invalid NTH16 signature <%#010x>\n",
1575 			  le32_to_cpu(nth16->dwSignature));
1576 		goto error;
1577 	}
1578 
1579 	len = le16_to_cpu(nth16->wBlockLength);
1580 	if (len > ctx->rx_max) {
1581 		netif_dbg(dev, rx_err, dev->net,
1582 			  "unsupported NTB block length %u/%u\n", len,
1583 			  ctx->rx_max);
1584 		goto error;
1585 	}
1586 
1587 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1588 	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1589 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1590 		netif_dbg(dev, rx_err, dev->net,
1591 			  "sequence number glitch prev=%d curr=%d\n",
1592 			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1593 	}
1594 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1595 
1596 	ret = le16_to_cpu(nth16->wNdpIndex);
1597 error:
1598 	return ret;
1599 }
1600 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1601 
1602 int cdc_ncm_rx_verify_nth32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1603 {
1604 	struct usbnet *dev = netdev_priv(skb_in->dev);
1605 	struct usb_cdc_ncm_nth32 *nth32;
1606 	int len;
1607 	int ret = -EINVAL;
1608 
1609 	if (ctx == NULL)
1610 		goto error;
1611 
1612 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth32) +
1613 					sizeof(struct usb_cdc_ncm_ndp32))) {
1614 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1615 		goto error;
1616 	}
1617 
1618 	nth32 = (struct usb_cdc_ncm_nth32 *)skb_in->data;
1619 
1620 	if (nth32->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH32_SIGN)) {
1621 		netif_dbg(dev, rx_err, dev->net,
1622 			  "invalid NTH32 signature <%#010x>\n",
1623 			  le32_to_cpu(nth32->dwSignature));
1624 		goto error;
1625 	}
1626 
1627 	len = le32_to_cpu(nth32->dwBlockLength);
1628 	if (len > ctx->rx_max) {
1629 		netif_dbg(dev, rx_err, dev->net,
1630 			  "unsupported NTB block length %u/%u\n", len,
1631 			  ctx->rx_max);
1632 		goto error;
1633 	}
1634 
1635 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth32->wSequence) &&
1636 	    (ctx->rx_seq || le16_to_cpu(nth32->wSequence)) &&
1637 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth32->wSequence))) {
1638 		netif_dbg(dev, rx_err, dev->net,
1639 			  "sequence number glitch prev=%d curr=%d\n",
1640 			  ctx->rx_seq, le16_to_cpu(nth32->wSequence));
1641 	}
1642 	ctx->rx_seq = le16_to_cpu(nth32->wSequence);
1643 
1644 	ret = le32_to_cpu(nth32->dwNdpIndex);
1645 error:
1646 	return ret;
1647 }
1648 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth32);
1649 
1650 /* verify NDP header and return number of datagrams, or negative error */
1651 int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1652 {
1653 	struct usbnet *dev = netdev_priv(skb_in->dev);
1654 	struct usb_cdc_ncm_ndp16 *ndp16;
1655 	int ret = -EINVAL;
1656 
1657 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1658 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1659 			  ndpoffset);
1660 		goto error;
1661 	}
1662 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1663 
1664 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1665 		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1666 			  le16_to_cpu(ndp16->wLength));
1667 		goto error;
1668 	}
1669 
1670 	ret = ((le16_to_cpu(ndp16->wLength) -
1671 					sizeof(struct usb_cdc_ncm_ndp16)) /
1672 					sizeof(struct usb_cdc_ncm_dpe16));
1673 	ret--; /* we process NDP entries except for the last one */
1674 
1675 	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1676 	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1677 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1678 		ret = -EINVAL;
1679 	}
1680 
1681 error:
1682 	return ret;
1683 }
1684 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1685 
1686 /* verify NDP header and return number of datagrams, or negative error */
1687 int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
1688 {
1689 	struct usbnet *dev = netdev_priv(skb_in->dev);
1690 	struct usb_cdc_ncm_ndp32 *ndp32;
1691 	int ret = -EINVAL;
1692 
1693 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp32)) > skb_in->len) {
1694 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1695 			  ndpoffset);
1696 		goto error;
1697 	}
1698 	ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1699 
1700 	if (le16_to_cpu(ndp32->wLength) < USB_CDC_NCM_NDP32_LENGTH_MIN) {
1701 		netif_dbg(dev, rx_err, dev->net, "invalid DPT32 length <%u>\n",
1702 			  le16_to_cpu(ndp32->wLength));
1703 		goto error;
1704 	}
1705 
1706 	ret = ((le16_to_cpu(ndp32->wLength) -
1707 					sizeof(struct usb_cdc_ncm_ndp32)) /
1708 					sizeof(struct usb_cdc_ncm_dpe32));
1709 	ret--; /* we process NDP entries except for the last one */
1710 
1711 	if ((sizeof(struct usb_cdc_ncm_ndp32) +
1712 	     ret * (sizeof(struct usb_cdc_ncm_dpe32))) > skb_in->len) {
1713 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1714 		ret = -EINVAL;
1715 	}
1716 
1717 error:
1718 	return ret;
1719 }
1720 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp32);
1721 
1722 int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1723 {
1724 	struct sk_buff *skb;
1725 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1726 	unsigned int len;
1727 	int nframes;
1728 	int x;
1729 	unsigned int offset;
1730 	union {
1731 		struct usb_cdc_ncm_ndp16 *ndp16;
1732 		struct usb_cdc_ncm_ndp32 *ndp32;
1733 	} ndp;
1734 	union {
1735 		struct usb_cdc_ncm_dpe16 *dpe16;
1736 		struct usb_cdc_ncm_dpe32 *dpe32;
1737 	} dpe;
1738 
1739 	int ndpoffset;
1740 	int loopcount = 50; /* arbitrary max preventing infinite loop */
1741 	u32 payload = 0;
1742 
1743 	if (ctx->is_ndp16)
1744 		ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1745 	else
1746 		ndpoffset = cdc_ncm_rx_verify_nth32(ctx, skb_in);
1747 
1748 	if (ndpoffset < 0)
1749 		goto error;
1750 
1751 next_ndp:
1752 	if (ctx->is_ndp16) {
1753 		nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1754 		if (nframes < 0)
1755 			goto error;
1756 
1757 		ndp.ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1758 
1759 		if (ndp.ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1760 			netif_dbg(dev, rx_err, dev->net,
1761 				  "invalid DPT16 signature <%#010x>\n",
1762 				  le32_to_cpu(ndp.ndp16->dwSignature));
1763 			goto err_ndp;
1764 		}
1765 		dpe.dpe16 = ndp.ndp16->dpe16;
1766 	} else {
1767 		nframes = cdc_ncm_rx_verify_ndp32(skb_in, ndpoffset);
1768 		if (nframes < 0)
1769 			goto error;
1770 
1771 		ndp.ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1772 
1773 		if (ndp.ndp32->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN)) {
1774 			netif_dbg(dev, rx_err, dev->net,
1775 				  "invalid DPT32 signature <%#010x>\n",
1776 				  le32_to_cpu(ndp.ndp32->dwSignature));
1777 			goto err_ndp;
1778 		}
1779 		dpe.dpe32 = ndp.ndp32->dpe32;
1780 	}
1781 
1782 	for (x = 0; x < nframes; x++) {
1783 		if (ctx->is_ndp16) {
1784 			offset = le16_to_cpu(dpe.dpe16->wDatagramIndex);
1785 			len = le16_to_cpu(dpe.dpe16->wDatagramLength);
1786 		} else {
1787 			offset = le32_to_cpu(dpe.dpe32->dwDatagramIndex);
1788 			len = le32_to_cpu(dpe.dpe32->dwDatagramLength);
1789 		}
1790 
1791 		/*
1792 		 * CDC NCM ch. 3.7
1793 		 * All entries after first NULL entry are to be ignored
1794 		 */
1795 		if ((offset == 0) || (len == 0)) {
1796 			if (!x)
1797 				goto err_ndp; /* empty NTB */
1798 			break;
1799 		}
1800 
1801 		/* sanity checking - watch out for integer wrap*/
1802 		if ((offset > skb_in->len) || (len > skb_in->len - offset) ||
1803 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1804 			netif_dbg(dev, rx_err, dev->net,
1805 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1806 				  x, offset, len, skb_in);
1807 			if (!x)
1808 				goto err_ndp;
1809 			break;
1810 
1811 		} else {
1812 			/* create a fresh copy to reduce truesize */
1813 			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1814 			if (!skb)
1815 				goto error;
1816 			skb_put_data(skb, skb_in->data + offset, len);
1817 			usbnet_skb_return(dev, skb);
1818 			payload += len;	/* count payload bytes in this NTB */
1819 		}
1820 
1821 		if (ctx->is_ndp16)
1822 			dpe.dpe16++;
1823 		else
1824 			dpe.dpe32++;
1825 	}
1826 err_ndp:
1827 	/* are there more NDPs to process? */
1828 	if (ctx->is_ndp16)
1829 		ndpoffset = le16_to_cpu(ndp.ndp16->wNextNdpIndex);
1830 	else
1831 		ndpoffset = le32_to_cpu(ndp.ndp32->dwNextNdpIndex);
1832 
1833 	if (ndpoffset && loopcount--)
1834 		goto next_ndp;
1835 
1836 	/* update stats */
1837 	ctx->rx_overhead += skb_in->len - payload;
1838 	ctx->rx_ntbs++;
1839 
1840 	return 1;
1841 error:
1842 	return 0;
1843 }
1844 EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1845 
1846 static void
1847 cdc_ncm_speed_change(struct usbnet *dev,
1848 		     struct usb_cdc_speed_change *data)
1849 {
1850 	/* RTL8156 shipped before 2021 sends notification about every 32ms. */
1851 	dev->rx_speed = le32_to_cpu(data->DLBitRRate);
1852 	dev->tx_speed = le32_to_cpu(data->ULBitRate);
1853 }
1854 
1855 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1856 {
1857 	struct usb_cdc_notification *event;
1858 
1859 	if (urb->actual_length < sizeof(*event))
1860 		return;
1861 
1862 	/* test for split data in 8-byte chunks */
1863 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1864 		cdc_ncm_speed_change(dev,
1865 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1866 		return;
1867 	}
1868 
1869 	event = urb->transfer_buffer;
1870 
1871 	switch (event->bNotificationType) {
1872 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1873 		/*
1874 		 * According to the CDC NCM specification ch.7.1
1875 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1876 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1877 		 */
1878 		/* RTL8156 shipped before 2021 sends notification about
1879 		 * every 32ms. Don't forward notification if state is same.
1880 		 */
1881 		if (netif_carrier_ok(dev->net) != !!event->wValue)
1882 			usbnet_link_change(dev, !!event->wValue, 0);
1883 		break;
1884 
1885 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1886 		if (urb->actual_length < (sizeof(*event) +
1887 					sizeof(struct usb_cdc_speed_change)))
1888 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1889 		else
1890 			cdc_ncm_speed_change(dev,
1891 					     (struct usb_cdc_speed_change *)&event[1]);
1892 		break;
1893 
1894 	default:
1895 		dev_dbg(&dev->udev->dev,
1896 			"NCM: unexpected notification 0x%02x!\n",
1897 			event->bNotificationType);
1898 		break;
1899 	}
1900 }
1901 
1902 static const struct driver_info cdc_ncm_info = {
1903 	.description = "CDC NCM (NO ZLP)",
1904 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1905 			| FLAG_LINK_INTR | FLAG_ETHER,
1906 	.bind = cdc_ncm_bind,
1907 	.unbind = cdc_ncm_unbind,
1908 	.manage_power = usbnet_manage_power,
1909 	.status = cdc_ncm_status,
1910 	.rx_fixup = cdc_ncm_rx_fixup,
1911 	.tx_fixup = cdc_ncm_tx_fixup,
1912 	.set_rx_mode = usbnet_cdc_update_filter,
1913 };
1914 
1915 /* Same as cdc_ncm_info, but with FLAG_SEND_ZLP  */
1916 static const struct driver_info cdc_ncm_zlp_info = {
1917 	.description = "CDC NCM (SEND ZLP)",
1918 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1919 			| FLAG_LINK_INTR | FLAG_ETHER | FLAG_SEND_ZLP,
1920 	.bind = cdc_ncm_bind,
1921 	.unbind = cdc_ncm_unbind,
1922 	.manage_power = usbnet_manage_power,
1923 	.status = cdc_ncm_status,
1924 	.rx_fixup = cdc_ncm_rx_fixup,
1925 	.tx_fixup = cdc_ncm_tx_fixup,
1926 	.set_rx_mode = usbnet_cdc_update_filter,
1927 };
1928 
1929 /* Same as cdc_ncm_info, but with FLAG_SEND_ZLP */
1930 static const struct driver_info apple_tethering_interface_info = {
1931 	.description = "CDC NCM (Apple Tethering)",
1932 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1933 			| FLAG_LINK_INTR | FLAG_ETHER | FLAG_SEND_ZLP,
1934 	.bind = cdc_ncm_bind,
1935 	.unbind = cdc_ncm_unbind,
1936 	.manage_power = usbnet_manage_power,
1937 	.status = cdc_ncm_status,
1938 	.rx_fixup = cdc_ncm_rx_fixup,
1939 	.tx_fixup = cdc_ncm_tx_fixup,
1940 	.set_rx_mode = usbnet_cdc_update_filter,
1941 };
1942 
1943 /* Same as apple_tethering_interface_info, but without FLAG_LINK_INTR */
1944 static const struct driver_info apple_private_interface_info = {
1945 	.description = "CDC NCM (Apple Private)",
1946 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1947 			| FLAG_ETHER | FLAG_SEND_ZLP,
1948 	.bind = cdc_ncm_bind,
1949 	.unbind = cdc_ncm_unbind,
1950 	.manage_power = usbnet_manage_power,
1951 	.status = cdc_ncm_status,
1952 	.rx_fixup = cdc_ncm_rx_fixup,
1953 	.tx_fixup = cdc_ncm_tx_fixup,
1954 	.set_rx_mode = usbnet_cdc_update_filter,
1955 };
1956 
1957 /* Same as cdc_ncm_info, but with FLAG_WWAN */
1958 static const struct driver_info wwan_info = {
1959 	.description = "Mobile Broadband Network Device",
1960 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1961 			| FLAG_LINK_INTR | FLAG_WWAN,
1962 	.bind = cdc_ncm_bind,
1963 	.unbind = cdc_ncm_unbind,
1964 	.manage_power = usbnet_manage_power,
1965 	.status = cdc_ncm_status,
1966 	.rx_fixup = cdc_ncm_rx_fixup,
1967 	.tx_fixup = cdc_ncm_tx_fixup,
1968 	.set_rx_mode = usbnet_cdc_update_filter,
1969 };
1970 
1971 /* Same as wwan_info, but with FLAG_NOARP  */
1972 static const struct driver_info wwan_noarp_info = {
1973 	.description = "Mobile Broadband Network Device (NO ARP)",
1974 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1975 			| FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP,
1976 	.bind = cdc_ncm_bind,
1977 	.unbind = cdc_ncm_unbind,
1978 	.manage_power = usbnet_manage_power,
1979 	.status = cdc_ncm_status,
1980 	.rx_fixup = cdc_ncm_rx_fixup,
1981 	.tx_fixup = cdc_ncm_tx_fixup,
1982 	.set_rx_mode = usbnet_cdc_update_filter,
1983 };
1984 
1985 static const struct usb_device_id cdc_devs[] = {
1986 	/* iPhone */
1987 	{ USB_DEVICE_INTERFACE_NUMBER(0x05ac, 0x12a8, 2),
1988 		.driver_info = (unsigned long)&apple_tethering_interface_info,
1989 	},
1990 	{ USB_DEVICE_INTERFACE_NUMBER(0x05ac, 0x12a8, 4),
1991 		.driver_info = (unsigned long)&apple_private_interface_info,
1992 	},
1993 
1994 	/* iPad */
1995 	{ USB_DEVICE_INTERFACE_NUMBER(0x05ac, 0x12ab, 2),
1996 		.driver_info = (unsigned long)&apple_tethering_interface_info,
1997 	},
1998 	{ USB_DEVICE_INTERFACE_NUMBER(0x05ac, 0x12ab, 4),
1999 		.driver_info = (unsigned long)&apple_private_interface_info,
2000 	},
2001 
2002 	/* Ericsson MBM devices like F5521gw */
2003 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2004 		| USB_DEVICE_ID_MATCH_VENDOR,
2005 	  .idVendor = 0x0bdb,
2006 	  .bInterfaceClass = USB_CLASS_COMM,
2007 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2008 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2009 	  .driver_info = (unsigned long) &wwan_info,
2010 	},
2011 
2012 	/* Telit LE910 V2 */
2013 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x0036,
2014 		USB_CLASS_COMM,
2015 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2016 	  .driver_info = (unsigned long)&wwan_noarp_info,
2017 	},
2018 
2019 	/* DW5812 LTE Verizon Mobile Broadband Card
2020 	 * Unlike DW5550 this device requires FLAG_NOARP
2021 	 */
2022 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bb,
2023 		USB_CLASS_COMM,
2024 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2025 	  .driver_info = (unsigned long)&wwan_noarp_info,
2026 	},
2027 
2028 	/* DW5813 LTE AT&T Mobile Broadband Card
2029 	 * Unlike DW5550 this device requires FLAG_NOARP
2030 	 */
2031 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bc,
2032 		USB_CLASS_COMM,
2033 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2034 	  .driver_info = (unsigned long)&wwan_noarp_info,
2035 	},
2036 
2037 	/* Dell branded MBM devices like DW5550 */
2038 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2039 		| USB_DEVICE_ID_MATCH_VENDOR,
2040 	  .idVendor = 0x413c,
2041 	  .bInterfaceClass = USB_CLASS_COMM,
2042 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2043 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2044 	  .driver_info = (unsigned long) &wwan_info,
2045 	},
2046 
2047 	/* Toshiba branded MBM devices */
2048 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2049 		| USB_DEVICE_ID_MATCH_VENDOR,
2050 	  .idVendor = 0x0930,
2051 	  .bInterfaceClass = USB_CLASS_COMM,
2052 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2053 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2054 	  .driver_info = (unsigned long) &wwan_info,
2055 	},
2056 
2057 	/* tag Huawei devices as wwan */
2058 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
2059 					USB_CLASS_COMM,
2060 					USB_CDC_SUBCLASS_NCM,
2061 					USB_CDC_PROTO_NONE),
2062 	  .driver_info = (unsigned long)&wwan_info,
2063 	},
2064 
2065 	/* Infineon(now Intel) HSPA Modem platform */
2066 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
2067 		USB_CLASS_COMM,
2068 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2069 	  .driver_info = (unsigned long)&wwan_noarp_info,
2070 	},
2071 
2072 	/* u-blox TOBY-L4 */
2073 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1546, 0x1010,
2074 		USB_CLASS_COMM,
2075 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2076 	  .driver_info = (unsigned long)&wwan_info,
2077 	},
2078 
2079 	/* DisplayLink docking stations */
2080 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
2081 		| USB_DEVICE_ID_MATCH_VENDOR,
2082 	  .idVendor = 0x17e9,
2083 	  .bInterfaceClass = USB_CLASS_COMM,
2084 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
2085 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
2086 	  .driver_info = (unsigned long)&cdc_ncm_zlp_info,
2087 	},
2088 
2089 	/* Generic CDC-NCM devices */
2090 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
2091 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2092 		.driver_info = (unsigned long)&cdc_ncm_info,
2093 	},
2094 	{
2095 	},
2096 };
2097 MODULE_DEVICE_TABLE(usb, cdc_devs);
2098 
2099 static struct usb_driver cdc_ncm_driver = {
2100 	.name = "cdc_ncm",
2101 	.id_table = cdc_devs,
2102 	.probe = usbnet_probe,
2103 	.disconnect = usbnet_disconnect,
2104 	.suspend = usbnet_suspend,
2105 	.resume = usbnet_resume,
2106 	.reset_resume =	usbnet_resume,
2107 	.supports_autosuspend = 1,
2108 	.disable_hub_initiated_lpm = 1,
2109 };
2110 
2111 module_usb_driver(cdc_ncm_driver);
2112 
2113 MODULE_AUTHOR("Hans Petter Selasky");
2114 MODULE_DESCRIPTION("USB CDC NCM host driver");
2115 MODULE_LICENSE("Dual BSD/GPL");
2116