xref: /openbmc/linux/drivers/net/usb/cdc_ncm.c (revision b737eecd)
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/workqueue.h>
47 #include <linux/mii.h>
48 #include <linux/crc32.h>
49 #include <linux/usb.h>
50 #include <linux/hrtimer.h>
51 #include <linux/atomic.h>
52 #include <linux/usb/usbnet.h>
53 #include <linux/usb/cdc.h>
54 #include <linux/usb/cdc_ncm.h>
55 
56 #if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
57 static bool prefer_mbim = true;
58 #else
59 static bool prefer_mbim;
60 #endif
61 module_param(prefer_mbim, bool, 0644);
62 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
63 
64 static void cdc_ncm_txpath_bh(struct tasklet_struct *t);
65 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
66 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
67 static struct usb_driver cdc_ncm_driver;
68 
69 struct cdc_ncm_stats {
70 	char stat_string[ETH_GSTRING_LEN];
71 	int sizeof_stat;
72 	int stat_offset;
73 };
74 
75 #define CDC_NCM_STAT(str, m) { \
76 		.stat_string = str, \
77 		.sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
78 		.stat_offset = offsetof(struct cdc_ncm_ctx, m) }
79 #define CDC_NCM_SIMPLE_STAT(m)	CDC_NCM_STAT(__stringify(m), m)
80 
81 static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
82 	CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
83 	CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
84 	CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
85 	CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
86 	CDC_NCM_SIMPLE_STAT(tx_overhead),
87 	CDC_NCM_SIMPLE_STAT(tx_ntbs),
88 	CDC_NCM_SIMPLE_STAT(rx_overhead),
89 	CDC_NCM_SIMPLE_STAT(rx_ntbs),
90 };
91 
92 #define CDC_NCM_LOW_MEM_MAX_CNT 10
93 
94 static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
95 {
96 	switch (sset) {
97 	case ETH_SS_STATS:
98 		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
99 	default:
100 		return -EOPNOTSUPP;
101 	}
102 }
103 
104 static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
105 				    struct ethtool_stats __always_unused *stats,
106 				    u64 *data)
107 {
108 	struct usbnet *dev = netdev_priv(netdev);
109 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
110 	int i;
111 	char *p = NULL;
112 
113 	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
114 		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
115 		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
116 	}
117 }
118 
119 static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
120 {
121 	u8 *p = data;
122 	int i;
123 
124 	switch (stringset) {
125 	case ETH_SS_STATS:
126 		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
127 			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
128 			p += ETH_GSTRING_LEN;
129 		}
130 	}
131 }
132 
133 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
134 
135 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
136 	.get_link          = usbnet_get_link,
137 	.nway_reset        = usbnet_nway_reset,
138 	.get_drvinfo       = usbnet_get_drvinfo,
139 	.get_msglevel      = usbnet_get_msglevel,
140 	.set_msglevel      = usbnet_set_msglevel,
141 	.get_ts_info       = ethtool_op_get_ts_info,
142 	.get_sset_count    = cdc_ncm_get_sset_count,
143 	.get_strings       = cdc_ncm_get_strings,
144 	.get_ethtool_stats = cdc_ncm_get_ethtool_stats,
145 	.get_link_ksettings      = usbnet_get_link_ksettings,
146 	.set_link_ksettings      = usbnet_set_link_ksettings,
147 };
148 
149 static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
150 {
151 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
152 	u32 val, max, min;
153 
154 	/* clamp new_rx to sane values */
155 	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
156 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
157 
158 	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
159 	if (max < min) {
160 		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
161 			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
162 		max = min;
163 	}
164 
165 	val = clamp_t(u32, new_rx, min, max);
166 	if (val != new_rx)
167 		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
168 
169 	return val;
170 }
171 
172 static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
173 {
174 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
175 	u32 val, max, min;
176 
177 	/* clamp new_tx to sane values */
178 	if (ctx->is_ndp16)
179 		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
180 	else
181 		min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth32);
182 
183 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_TX, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
184 
185 	/* some devices set dwNtbOutMaxSize too low for the above default */
186 	min = min(min, max);
187 
188 	val = clamp_t(u32, new_tx, min, max);
189 	if (val != new_tx)
190 		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
191 
192 	return val;
193 }
194 
195 static ssize_t cdc_ncm_show_min_tx_pkt(struct device *d, struct device_attribute *attr, char *buf)
196 {
197 	struct usbnet *dev = netdev_priv(to_net_dev(d));
198 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
199 
200 	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
201 }
202 
203 static ssize_t cdc_ncm_show_rx_max(struct device *d, struct device_attribute *attr, char *buf)
204 {
205 	struct usbnet *dev = netdev_priv(to_net_dev(d));
206 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
207 
208 	return sprintf(buf, "%u\n", ctx->rx_max);
209 }
210 
211 static ssize_t cdc_ncm_show_tx_max(struct device *d, 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->tx_max);
217 }
218 
219 static ssize_t cdc_ncm_show_tx_timer_usecs(struct device *d, struct device_attribute *attr, char *buf)
220 {
221 	struct usbnet *dev = netdev_priv(to_net_dev(d));
222 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
223 
224 	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
225 }
226 
227 static ssize_t cdc_ncm_store_min_tx_pkt(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
228 {
229 	struct usbnet *dev = netdev_priv(to_net_dev(d));
230 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
231 	unsigned long val;
232 
233 	/* no need to restrict values - anything from 0 to infinity is OK */
234 	if (kstrtoul(buf, 0, &val))
235 		return -EINVAL;
236 
237 	ctx->min_tx_pkt = val;
238 	return len;
239 }
240 
241 static ssize_t cdc_ncm_store_rx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
242 {
243 	struct usbnet *dev = netdev_priv(to_net_dev(d));
244 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
245 	unsigned long val;
246 
247 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
248 		return -EINVAL;
249 
250 	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
251 	return len;
252 }
253 
254 static ssize_t cdc_ncm_store_tx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
255 {
256 	struct usbnet *dev = netdev_priv(to_net_dev(d));
257 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
258 	unsigned long val;
259 
260 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
261 		return -EINVAL;
262 
263 	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
264 	return len;
265 }
266 
267 static ssize_t cdc_ncm_store_tx_timer_usecs(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
268 {
269 	struct usbnet *dev = netdev_priv(to_net_dev(d));
270 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
271 	ssize_t ret;
272 	unsigned long val;
273 
274 	ret = kstrtoul(buf, 0, &val);
275 	if (ret)
276 		return ret;
277 	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
278 		return -EINVAL;
279 
280 	spin_lock_bh(&ctx->mtx);
281 	ctx->timer_interval = val * NSEC_PER_USEC;
282 	if (!ctx->timer_interval)
283 		ctx->tx_timer_pending = 0;
284 	spin_unlock_bh(&ctx->mtx);
285 	return len;
286 }
287 
288 static DEVICE_ATTR(min_tx_pkt, 0644, cdc_ncm_show_min_tx_pkt, cdc_ncm_store_min_tx_pkt);
289 static DEVICE_ATTR(rx_max, 0644, cdc_ncm_show_rx_max, cdc_ncm_store_rx_max);
290 static DEVICE_ATTR(tx_max, 0644, cdc_ncm_show_tx_max, cdc_ncm_store_tx_max);
291 static DEVICE_ATTR(tx_timer_usecs, 0644, cdc_ncm_show_tx_timer_usecs, cdc_ncm_store_tx_timer_usecs);
292 
293 static ssize_t ndp_to_end_show(struct device *d, struct device_attribute *attr, char *buf)
294 {
295 	struct usbnet *dev = netdev_priv(to_net_dev(d));
296 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
297 
298 	return sprintf(buf, "%c\n", ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END ? 'Y' : 'N');
299 }
300 
301 static ssize_t ndp_to_end_store(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
302 {
303 	struct usbnet *dev = netdev_priv(to_net_dev(d));
304 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
305 	bool enable;
306 
307 	if (strtobool(buf, &enable))
308 		return -EINVAL;
309 
310 	/* no change? */
311 	if (enable == (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
312 		return len;
313 
314 	if (enable) {
315 		if (ctx->is_ndp16 && !ctx->delayed_ndp16) {
316 			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
317 			if (!ctx->delayed_ndp16)
318 				return -ENOMEM;
319 		}
320 		if (!ctx->is_ndp16 && !ctx->delayed_ndp32) {
321 			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
322 			if (!ctx->delayed_ndp32)
323 				return -ENOMEM;
324 		}
325 	}
326 
327 	/* flush pending data before changing flag */
328 	netif_tx_lock_bh(dev->net);
329 	usbnet_start_xmit(NULL, dev->net);
330 	spin_lock_bh(&ctx->mtx);
331 	if (enable)
332 		ctx->drvflags |= CDC_NCM_FLAG_NDP_TO_END;
333 	else
334 		ctx->drvflags &= ~CDC_NCM_FLAG_NDP_TO_END;
335 	spin_unlock_bh(&ctx->mtx);
336 	netif_tx_unlock_bh(dev->net);
337 
338 	return len;
339 }
340 static DEVICE_ATTR_RW(ndp_to_end);
341 
342 #define NCM_PARM_ATTR(name, format, tocpu)				\
343 static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
344 { \
345 	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
346 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
347 	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
348 } \
349 static DEVICE_ATTR(name, 0444, cdc_ncm_show_##name, NULL)
350 
351 NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
352 NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
353 NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
354 NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
355 NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
356 NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
357 NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
358 NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
359 NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
360 NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
361 
362 static struct attribute *cdc_ncm_sysfs_attrs[] = {
363 	&dev_attr_min_tx_pkt.attr,
364 	&dev_attr_ndp_to_end.attr,
365 	&dev_attr_rx_max.attr,
366 	&dev_attr_tx_max.attr,
367 	&dev_attr_tx_timer_usecs.attr,
368 	&dev_attr_bmNtbFormatsSupported.attr,
369 	&dev_attr_dwNtbInMaxSize.attr,
370 	&dev_attr_wNdpInDivisor.attr,
371 	&dev_attr_wNdpInPayloadRemainder.attr,
372 	&dev_attr_wNdpInAlignment.attr,
373 	&dev_attr_dwNtbOutMaxSize.attr,
374 	&dev_attr_wNdpOutDivisor.attr,
375 	&dev_attr_wNdpOutPayloadRemainder.attr,
376 	&dev_attr_wNdpOutAlignment.attr,
377 	&dev_attr_wNtbOutMaxDatagrams.attr,
378 	NULL,
379 };
380 
381 static const struct attribute_group cdc_ncm_sysfs_attr_group = {
382 	.name = "cdc_ncm",
383 	.attrs = cdc_ncm_sysfs_attrs,
384 };
385 
386 /* handle rx_max and tx_max changes */
387 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
388 {
389 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
390 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
391 	u32 val;
392 
393 	val = cdc_ncm_check_rx_max(dev, new_rx);
394 
395 	/* inform device about NTB input size changes */
396 	if (val != ctx->rx_max) {
397 		__le32 dwNtbInMaxSize = cpu_to_le32(val);
398 
399 		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
400 
401 		/* tell device to use new size */
402 		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
403 				     USB_TYPE_CLASS | USB_DIR_OUT
404 				     | USB_RECIP_INTERFACE,
405 				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
406 			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
407 		else
408 			ctx->rx_max = val;
409 	}
410 
411 	/* usbnet use these values for sizing rx queues */
412 	if (dev->rx_urb_size != ctx->rx_max) {
413 		dev->rx_urb_size = ctx->rx_max;
414 		if (netif_running(dev->net))
415 			usbnet_unlink_rx_urbs(dev);
416 	}
417 
418 	val = cdc_ncm_check_tx_max(dev, new_tx);
419 	if (val != ctx->tx_max)
420 		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
421 
422 	/* Adding a pad byte here if necessary simplifies the handling
423 	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
424 	 * the real skb max size.
425 	 *
426 	 * We cannot use dev->maxpacket here because this is called from
427 	 * .bind which is called before usbnet sets up dev->maxpacket
428 	 */
429 	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
430 	    val % usb_maxpacket(dev->udev, dev->out, 1) == 0)
431 		val++;
432 
433 	/* we might need to flush any pending tx buffers if running */
434 	if (netif_running(dev->net) && val > ctx->tx_max) {
435 		netif_tx_lock_bh(dev->net);
436 		usbnet_start_xmit(NULL, dev->net);
437 		/* make sure tx_curr_skb is reallocated if it was empty */
438 		if (ctx->tx_curr_skb) {
439 			dev_kfree_skb_any(ctx->tx_curr_skb);
440 			ctx->tx_curr_skb = NULL;
441 		}
442 		ctx->tx_max = val;
443 		netif_tx_unlock_bh(dev->net);
444 	} else {
445 		ctx->tx_max = val;
446 	}
447 
448 	dev->hard_mtu = ctx->tx_max;
449 
450 	/* max qlen depend on hard_mtu and rx_urb_size */
451 	usbnet_update_max_qlen(dev);
452 
453 	/* never pad more than 3 full USB packets per transfer */
454 	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out, 1),
455 				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
456 }
457 
458 /* helpers for NCM and MBIM differences */
459 static u8 cdc_ncm_flags(struct usbnet *dev)
460 {
461 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
462 
463 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
464 		return ctx->mbim_desc->bmNetworkCapabilities;
465 	if (ctx->func_desc)
466 		return ctx->func_desc->bmNetworkCapabilities;
467 	return 0;
468 }
469 
470 static int cdc_ncm_eth_hlen(struct usbnet *dev)
471 {
472 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
473 		return 0;
474 	return ETH_HLEN;
475 }
476 
477 static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
478 {
479 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
480 		return CDC_MBIM_MIN_DATAGRAM_SIZE;
481 	return CDC_NCM_MIN_DATAGRAM_SIZE;
482 }
483 
484 static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
485 {
486 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
487 
488 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
489 		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
490 	if (ctx->ether_desc)
491 		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
492 	return CDC_NCM_MAX_DATAGRAM_SIZE;
493 }
494 
495 /* initial one-time device setup.  MUST be called with the data interface
496  * in altsetting 0
497  */
498 static int cdc_ncm_init(struct usbnet *dev)
499 {
500 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
501 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
502 	int err;
503 
504 	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
505 			      USB_TYPE_CLASS | USB_DIR_IN
506 			      |USB_RECIP_INTERFACE,
507 			      0, iface_no, &ctx->ncm_parm,
508 			      sizeof(ctx->ncm_parm));
509 	if (err < 0) {
510 		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
511 		return err; /* GET_NTB_PARAMETERS is required */
512 	}
513 
514 	/* set CRC Mode */
515 	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
516 		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
517 		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
518 				       USB_TYPE_CLASS | USB_DIR_OUT
519 				       | USB_RECIP_INTERFACE,
520 				       USB_CDC_NCM_CRC_NOT_APPENDED,
521 				       iface_no, NULL, 0);
522 		if (err < 0)
523 			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
524 	}
525 
526 	/* use ndp16 by default */
527 	ctx->is_ndp16 = 1;
528 
529 	/* set NTB format, if both formats are supported.
530 	 *
531 	 * "The host shall only send this command while the NCM Data
532 	 *  Interface is in alternate setting 0."
533 	 */
534 	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
535 						USB_CDC_NCM_NTB32_SUPPORTED) {
536 		if (ctx->drvflags & CDC_NCM_FLAG_PREFER_NTB32) {
537 			ctx->is_ndp16 = 0;
538 			dev_dbg(&dev->intf->dev, "Setting NTB format to 32-bit\n");
539 			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
540 					       USB_TYPE_CLASS | USB_DIR_OUT
541 					       | USB_RECIP_INTERFACE,
542 					       USB_CDC_NCM_NTB32_FORMAT,
543 					       iface_no, NULL, 0);
544 		} else {
545 			ctx->is_ndp16 = 1;
546 			dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
547 			err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
548 					       USB_TYPE_CLASS | USB_DIR_OUT
549 					       | USB_RECIP_INTERFACE,
550 					       USB_CDC_NCM_NTB16_FORMAT,
551 					       iface_no, NULL, 0);
552 		}
553 		if (err < 0) {
554 			ctx->is_ndp16 = 1;
555 			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
556 		}
557 	}
558 
559 	/* set initial device values */
560 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
561 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
562 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
563 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
564 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
565 	/* devices prior to NCM Errata shall set this field to zero */
566 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
567 
568 	dev_dbg(&dev->intf->dev,
569 		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
570 		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
571 		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
572 
573 	/* max count of tx datagrams */
574 	if ((ctx->tx_max_datagrams == 0) ||
575 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
576 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
577 
578 	/* set up maximum NDP size */
579 	if (ctx->is_ndp16)
580 		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
581 	else
582 		ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp32) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe32);
583 
584 	/* initial coalescing timer interval */
585 	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
586 
587 	return 0;
588 }
589 
590 /* set a new max datagram size */
591 static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
592 {
593 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
594 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
595 	__le16 max_datagram_size;
596 	u16 mbim_mtu;
597 	int err;
598 
599 	/* set default based on descriptors */
600 	ctx->max_datagram_size = clamp_t(u32, new_size,
601 					 cdc_ncm_min_dgram_size(dev),
602 					 CDC_NCM_MAX_DATAGRAM_SIZE);
603 
604 	/* inform the device about the selected Max Datagram Size? */
605 	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
606 		goto out;
607 
608 	/* read current mtu value from device */
609 	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
610 			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
611 			      0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
612 	if (err != sizeof(max_datagram_size)) {
613 		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
614 		goto out;
615 	}
616 
617 	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
618 		goto out;
619 
620 	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
621 	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
622 			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
623 			       0, iface_no, &max_datagram_size, sizeof(max_datagram_size));
624 	if (err < 0)
625 		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
626 
627 out:
628 	/* set MTU to max supported by the device if necessary */
629 	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
630 
631 	/* do not exceed operater preferred MTU */
632 	if (ctx->mbim_extended_desc) {
633 		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
634 		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
635 			dev->net->mtu = mbim_mtu;
636 	}
637 }
638 
639 static void cdc_ncm_fix_modulus(struct usbnet *dev)
640 {
641 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
642 	u32 val;
643 
644 	/*
645 	 * verify that the structure alignment is:
646 	 * - power of two
647 	 * - not greater than the maximum transmit length
648 	 * - not less than four bytes
649 	 */
650 	val = ctx->tx_ndp_modulus;
651 
652 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
653 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
654 		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
655 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
656 	}
657 
658 	/*
659 	 * verify that the payload alignment is:
660 	 * - power of two
661 	 * - not greater than the maximum transmit length
662 	 * - not less than four bytes
663 	 */
664 	val = ctx->tx_modulus;
665 
666 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
667 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
668 		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
669 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
670 	}
671 
672 	/* verify the payload remainder */
673 	if (ctx->tx_remainder >= ctx->tx_modulus) {
674 		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
675 		ctx->tx_remainder = 0;
676 	}
677 
678 	/* adjust TX-remainder according to NCM specification. */
679 	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
680 			     (ctx->tx_modulus - 1));
681 }
682 
683 static int cdc_ncm_setup(struct usbnet *dev)
684 {
685 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
686 	u32 def_rx, def_tx;
687 
688 	/* be conservative when selecting intial buffer size to
689 	 * increase the number of hosts this will work for
690 	 */
691 	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
692 		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
693 	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
694 		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
695 
696 	/* clamp rx_max and tx_max and inform device */
697 	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
698 
699 	/* sanitize the modulus and remainder values */
700 	cdc_ncm_fix_modulus(dev);
701 
702 	/* set max datagram size */
703 	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
704 	return 0;
705 }
706 
707 static void
708 cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
709 {
710 	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
711 	u8 ep;
712 
713 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
714 		e = intf->cur_altsetting->endpoint + ep;
715 
716 		/* ignore endpoints which cannot transfer data */
717 		if (!usb_endpoint_maxp(&e->desc))
718 			continue;
719 
720 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
721 		case USB_ENDPOINT_XFER_INT:
722 			if (usb_endpoint_dir_in(&e->desc)) {
723 				if (!dev->status)
724 					dev->status = e;
725 			}
726 			break;
727 
728 		case USB_ENDPOINT_XFER_BULK:
729 			if (usb_endpoint_dir_in(&e->desc)) {
730 				if (!in)
731 					in = e;
732 			} else {
733 				if (!out)
734 					out = e;
735 			}
736 			break;
737 
738 		default:
739 			break;
740 		}
741 	}
742 	if (in && !dev->in)
743 		dev->in = usb_rcvbulkpipe(dev->udev,
744 					  in->desc.bEndpointAddress &
745 					  USB_ENDPOINT_NUMBER_MASK);
746 	if (out && !dev->out)
747 		dev->out = usb_sndbulkpipe(dev->udev,
748 					   out->desc.bEndpointAddress &
749 					   USB_ENDPOINT_NUMBER_MASK);
750 }
751 
752 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
753 {
754 	if (ctx == NULL)
755 		return;
756 
757 	if (ctx->tx_rem_skb != NULL) {
758 		dev_kfree_skb_any(ctx->tx_rem_skb);
759 		ctx->tx_rem_skb = NULL;
760 	}
761 
762 	if (ctx->tx_curr_skb != NULL) {
763 		dev_kfree_skb_any(ctx->tx_curr_skb);
764 		ctx->tx_curr_skb = NULL;
765 	}
766 
767 	if (ctx->is_ndp16)
768 		kfree(ctx->delayed_ndp16);
769 	else
770 		kfree(ctx->delayed_ndp32);
771 
772 	kfree(ctx);
773 }
774 
775 /* we need to override the usbnet change_mtu ndo for two reasons:
776  *  - respect the negotiated maximum datagram size
777  *  - avoid unwanted changes to rx and tx buffers
778  */
779 int cdc_ncm_change_mtu(struct net_device *net, int new_mtu)
780 {
781 	struct usbnet *dev = netdev_priv(net);
782 
783 	net->mtu = new_mtu;
784 	cdc_ncm_set_dgram_size(dev, new_mtu + cdc_ncm_eth_hlen(dev));
785 
786 	return 0;
787 }
788 EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu);
789 
790 static const struct net_device_ops cdc_ncm_netdev_ops = {
791 	.ndo_open	     = usbnet_open,
792 	.ndo_stop	     = usbnet_stop,
793 	.ndo_start_xmit	     = usbnet_start_xmit,
794 	.ndo_tx_timeout	     = usbnet_tx_timeout,
795 	.ndo_set_rx_mode     = usbnet_set_rx_mode,
796 	.ndo_get_stats64     = dev_get_tstats64,
797 	.ndo_change_mtu	     = cdc_ncm_change_mtu,
798 	.ndo_set_mac_address = eth_mac_addr,
799 	.ndo_validate_addr   = eth_validate_addr,
800 };
801 
802 int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
803 {
804 	struct cdc_ncm_ctx *ctx;
805 	struct usb_driver *driver;
806 	u8 *buf;
807 	int len;
808 	int temp;
809 	u8 iface_no;
810 	struct usb_cdc_parsed_header hdr;
811 
812 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
813 	if (!ctx)
814 		return -ENOMEM;
815 
816 	ctx->dev = dev;
817 
818 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
819 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
820 	tasklet_setup(&ctx->bh, cdc_ncm_txpath_bh);
821 	atomic_set(&ctx->stop, 0);
822 	spin_lock_init(&ctx->mtx);
823 
824 	/* store ctx pointer in device data field */
825 	dev->data[0] = (unsigned long)ctx;
826 
827 	/* only the control interface can be successfully probed */
828 	ctx->control = intf;
829 
830 	/* get some pointers */
831 	driver = driver_of(intf);
832 	buf = intf->cur_altsetting->extra;
833 	len = intf->cur_altsetting->extralen;
834 
835 	/* parse through descriptors associated with control interface */
836 	cdc_parse_cdc_header(&hdr, intf, buf, len);
837 
838 	if (hdr.usb_cdc_union_desc)
839 		ctx->data = usb_ifnum_to_if(dev->udev,
840 					    hdr.usb_cdc_union_desc->bSlaveInterface0);
841 	ctx->ether_desc = hdr.usb_cdc_ether_desc;
842 	ctx->func_desc = hdr.usb_cdc_ncm_desc;
843 	ctx->mbim_desc = hdr.usb_cdc_mbim_desc;
844 	ctx->mbim_extended_desc = hdr.usb_cdc_mbim_extended_desc;
845 
846 	/* some buggy devices have an IAD but no CDC Union */
847 	if (!hdr.usb_cdc_union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
848 		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
849 		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
850 	}
851 
852 	/* check if we got everything */
853 	if (!ctx->data) {
854 		dev_err(&intf->dev, "CDC Union missing and no IAD found\n");
855 		goto error;
856 	}
857 	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
858 		if (!ctx->mbim_desc) {
859 			dev_err(&intf->dev, "MBIM functional descriptor missing\n");
860 			goto error;
861 		}
862 	} else {
863 		if (!ctx->ether_desc || !ctx->func_desc) {
864 			dev_err(&intf->dev, "NCM or ECM functional descriptors missing\n");
865 			goto error;
866 		}
867 	}
868 
869 	/* claim data interface, if different from control */
870 	if (ctx->data != ctx->control) {
871 		temp = usb_driver_claim_interface(driver, ctx->data, dev);
872 		if (temp) {
873 			dev_err(&intf->dev, "failed to claim data intf\n");
874 			goto error;
875 		}
876 	}
877 
878 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
879 
880 	/* Device-specific flags */
881 	ctx->drvflags = drvflags;
882 
883 	/* Reset data interface. Some devices will not reset properly
884 	 * unless they are configured first.  Toggle the altsetting to
885 	 * force a reset.
886 	 * Some other devices do not work properly with this procedure
887 	 * that can be avoided using quirk CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE
888 	 */
889 	if (!(ctx->drvflags & CDC_MBIM_FLAG_AVOID_ALTSETTING_TOGGLE))
890 		usb_set_interface(dev->udev, iface_no, data_altsetting);
891 
892 	temp = usb_set_interface(dev->udev, iface_no, 0);
893 	if (temp) {
894 		dev_dbg(&intf->dev, "set interface failed\n");
895 		goto error2;
896 	}
897 
898 	/* initialize basic device settings */
899 	if (cdc_ncm_init(dev))
900 		goto error2;
901 
902 	/* Some firmwares need a pause here or they will silently fail
903 	 * to set up the interface properly.  This value was decided
904 	 * empirically on a Sierra Wireless MC7455 running 02.08.02.00
905 	 * firmware.
906 	 */
907 	usleep_range(10000, 20000);
908 
909 	/* configure data interface */
910 	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
911 	if (temp) {
912 		dev_dbg(&intf->dev, "set interface failed\n");
913 		goto error2;
914 	}
915 
916 	cdc_ncm_find_endpoints(dev, ctx->data);
917 	cdc_ncm_find_endpoints(dev, ctx->control);
918 	if (!dev->in || !dev->out || !dev->status) {
919 		dev_dbg(&intf->dev, "failed to collect endpoints\n");
920 		goto error2;
921 	}
922 
923 	usb_set_intfdata(ctx->data, dev);
924 	usb_set_intfdata(ctx->control, dev);
925 
926 	if (ctx->ether_desc) {
927 		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
928 		if (temp) {
929 			dev_err(&intf->dev, "failed to get mac address\n");
930 			goto error2;
931 		}
932 		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
933 	}
934 
935 	/* finish setting up the device specific data */
936 	cdc_ncm_setup(dev);
937 
938 	/* Allocate the delayed NDP if needed. */
939 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
940 		if (ctx->is_ndp16) {
941 			ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
942 			if (!ctx->delayed_ndp16)
943 				goto error2;
944 		} else {
945 			ctx->delayed_ndp32 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
946 			if (!ctx->delayed_ndp32)
947 				goto error2;
948 		}
949 		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
950 	}
951 
952 	/* override ethtool_ops */
953 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
954 
955 	/* add our sysfs attrs */
956 	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
957 
958 	/* must handle MTU changes */
959 	dev->net->netdev_ops = &cdc_ncm_netdev_ops;
960 	dev->net->max_mtu = cdc_ncm_max_dgram_size(dev) - cdc_ncm_eth_hlen(dev);
961 
962 	return 0;
963 
964 error2:
965 	usb_set_intfdata(ctx->control, NULL);
966 	usb_set_intfdata(ctx->data, NULL);
967 	if (ctx->data != ctx->control)
968 		usb_driver_release_interface(driver, ctx->data);
969 error:
970 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
971 	dev->data[0] = 0;
972 	dev_info(&intf->dev, "bind() failure\n");
973 	return -ENODEV;
974 }
975 EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
976 
977 void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
978 {
979 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
980 	struct usb_driver *driver = driver_of(intf);
981 
982 	if (ctx == NULL)
983 		return;		/* no setup */
984 
985 	atomic_set(&ctx->stop, 1);
986 
987 	hrtimer_cancel(&ctx->tx_timer);
988 
989 	tasklet_kill(&ctx->bh);
990 
991 	/* handle devices with combined control and data interface */
992 	if (ctx->control == ctx->data)
993 		ctx->data = NULL;
994 
995 	/* disconnect master --> disconnect slave */
996 	if (intf == ctx->control && ctx->data) {
997 		usb_set_intfdata(ctx->data, NULL);
998 		usb_driver_release_interface(driver, ctx->data);
999 		ctx->data = NULL;
1000 
1001 	} else if (intf == ctx->data && ctx->control) {
1002 		usb_set_intfdata(ctx->control, NULL);
1003 		usb_driver_release_interface(driver, ctx->control);
1004 		ctx->control = NULL;
1005 	}
1006 
1007 	usb_set_intfdata(intf, NULL);
1008 	cdc_ncm_free(ctx);
1009 }
1010 EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
1011 
1012 /* Return the number of the MBIM control interface altsetting iff it
1013  * is preferred and available,
1014  */
1015 u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
1016 {
1017 	struct usb_host_interface *alt;
1018 
1019 	/* The MBIM spec defines a NCM compatible default altsetting,
1020 	 * which we may have matched:
1021 	 *
1022 	 *  "Functions that implement both NCM 1.0 and MBIM (an
1023 	 *   “NCM/MBIM function”) according to this recommendation
1024 	 *   shall provide two alternate settings for the
1025 	 *   Communication Interface.  Alternate setting 0, and the
1026 	 *   associated class and endpoint descriptors, shall be
1027 	 *   constructed according to the rules given for the
1028 	 *   Communication Interface in section 5 of [USBNCM10].
1029 	 *   Alternate setting 1, and the associated class and
1030 	 *   endpoint descriptors, shall be constructed according to
1031 	 *   the rules given in section 6 (USB Device Model) of this
1032 	 *   specification."
1033 	 */
1034 	if (intf->num_altsetting < 2)
1035 		return intf->cur_altsetting->desc.bAlternateSetting;
1036 
1037 	if (prefer_mbim) {
1038 		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
1039 		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
1040 			return CDC_NCM_COMM_ALTSETTING_MBIM;
1041 	}
1042 	return CDC_NCM_COMM_ALTSETTING_NCM;
1043 }
1044 EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
1045 
1046 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
1047 {
1048 	/* MBIM backwards compatible function? */
1049 	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
1050 		return -ENODEV;
1051 
1052 	/* The NCM data altsetting is fixed, so we hard-coded it.
1053 	 * Additionally, generic NCM devices are assumed to accept arbitrarily
1054 	 * placed NDP.
1055 	 */
1056 	return cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
1057 }
1058 
1059 static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
1060 {
1061 	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
1062 
1063 	if (skb->len + align > max)
1064 		align = max - skb->len;
1065 	if (align && skb_tailroom(skb) >= align)
1066 		skb_put_zero(skb, align);
1067 }
1068 
1069 /* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
1070  * allocating a new one within skb
1071  */
1072 static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1073 {
1074 	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1075 	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1076 	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1077 
1078 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1079 	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1080 	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1081 	*/
1082 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1083 		if (ctx->delayed_ndp16->dwSignature == sign)
1084 			return ctx->delayed_ndp16;
1085 
1086 		/* We can only push a single NDP to the end. Return
1087 		 * NULL to send what we've already got and queue this
1088 		 * skb for later.
1089 		 */
1090 		else if (ctx->delayed_ndp16->dwSignature)
1091 			return NULL;
1092 	}
1093 
1094 	/* follow the chain of NDPs, looking for a match */
1095 	while (ndpoffset) {
1096 		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1097 		if  (ndp16->dwSignature == sign)
1098 			return ndp16;
1099 		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1100 	}
1101 
1102 	/* align new NDP */
1103 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1104 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1105 
1106 	/* verify that there is room for the NDP and the datagram (reserve) */
1107 	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1108 		return NULL;
1109 
1110 	/* link to it */
1111 	if (ndp16)
1112 		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1113 	else
1114 		nth16->wNdpIndex = cpu_to_le16(skb->len);
1115 
1116 	/* push a new empty NDP */
1117 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1118 		ndp16 = skb_put_zero(skb, ctx->max_ndp_size);
1119 	else
1120 		ndp16 = ctx->delayed_ndp16;
1121 
1122 	ndp16->dwSignature = sign;
1123 	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1124 	return ndp16;
1125 }
1126 
1127 static struct usb_cdc_ncm_ndp32 *cdc_ncm_ndp32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1128 {
1129 	struct usb_cdc_ncm_ndp32 *ndp32 = NULL;
1130 	struct usb_cdc_ncm_nth32 *nth32 = (void *)skb->data;
1131 	size_t ndpoffset = le32_to_cpu(nth32->dwNdpIndex);
1132 
1133 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1134 	 * NTH32 header as we would normally do. NDP isn't written to the SKB yet, and
1135 	 * the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1136 	 */
1137 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1138 		if (ctx->delayed_ndp32->dwSignature == sign)
1139 			return ctx->delayed_ndp32;
1140 
1141 		/* We can only push a single NDP to the end. Return
1142 		 * NULL to send what we've already got and queue this
1143 		 * skb for later.
1144 		 */
1145 		else if (ctx->delayed_ndp32->dwSignature)
1146 			return NULL;
1147 	}
1148 
1149 	/* follow the chain of NDPs, looking for a match */
1150 	while (ndpoffset) {
1151 		ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb->data + ndpoffset);
1152 		if  (ndp32->dwSignature == sign)
1153 			return ndp32;
1154 		ndpoffset = le32_to_cpu(ndp32->dwNextNdpIndex);
1155 	}
1156 
1157 	/* align new NDP */
1158 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1159 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size);
1160 
1161 	/* verify that there is room for the NDP and the datagram (reserve) */
1162 	if ((ctx->tx_curr_size - skb->len - reserve) < ctx->max_ndp_size)
1163 		return NULL;
1164 
1165 	/* link to it */
1166 	if (ndp32)
1167 		ndp32->dwNextNdpIndex = cpu_to_le32(skb->len);
1168 	else
1169 		nth32->dwNdpIndex = cpu_to_le32(skb->len);
1170 
1171 	/* push a new empty NDP */
1172 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1173 		ndp32 = skb_put_zero(skb, ctx->max_ndp_size);
1174 	else
1175 		ndp32 = ctx->delayed_ndp32;
1176 
1177 	ndp32->dwSignature = sign;
1178 	ndp32->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp32) + sizeof(struct usb_cdc_ncm_dpe32));
1179 	return ndp32;
1180 }
1181 
1182 struct sk_buff *
1183 cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1184 {
1185 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1186 	union {
1187 		struct usb_cdc_ncm_nth16 *nth16;
1188 		struct usb_cdc_ncm_nth32 *nth32;
1189 	} nth;
1190 	union {
1191 		struct usb_cdc_ncm_ndp16 *ndp16;
1192 		struct usb_cdc_ncm_ndp32 *ndp32;
1193 	} ndp;
1194 	struct sk_buff *skb_out;
1195 	u16 n = 0, index, ndplen;
1196 	u8 ready2send = 0;
1197 	u32 delayed_ndp_size;
1198 	size_t padding_count;
1199 
1200 	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1201 	 * accordingly. Otherwise, we should check here.
1202 	 */
1203 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1204 		delayed_ndp_size = ctx->max_ndp_size +
1205 			max_t(u32,
1206 			      ctx->tx_ndp_modulus,
1207 			      ctx->tx_modulus + ctx->tx_remainder) - 1;
1208 	else
1209 		delayed_ndp_size = 0;
1210 
1211 	/* if there is a remaining skb, it gets priority */
1212 	if (skb != NULL) {
1213 		swap(skb, ctx->tx_rem_skb);
1214 		swap(sign, ctx->tx_rem_sign);
1215 	} else {
1216 		ready2send = 1;
1217 	}
1218 
1219 	/* check if we are resuming an OUT skb */
1220 	skb_out = ctx->tx_curr_skb;
1221 
1222 	/* allocate a new OUT skb */
1223 	if (!skb_out) {
1224 		if (ctx->tx_low_mem_val == 0) {
1225 			ctx->tx_curr_size = ctx->tx_max;
1226 			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1227 			/* If the memory allocation fails we will wait longer
1228 			 * each time before attempting another full size
1229 			 * allocation again to not overload the system
1230 			 * further.
1231 			 */
1232 			if (skb_out == NULL) {
1233 				ctx->tx_low_mem_max_cnt = min(ctx->tx_low_mem_max_cnt + 1,
1234 							      (unsigned)CDC_NCM_LOW_MEM_MAX_CNT);
1235 				ctx->tx_low_mem_val = ctx->tx_low_mem_max_cnt;
1236 			}
1237 		}
1238 		if (skb_out == NULL) {
1239 			/* See if a very small allocation is possible.
1240 			 * We will send this packet immediately and hope
1241 			 * that there is more memory available later.
1242 			 */
1243 			if (skb)
1244 				ctx->tx_curr_size = max(skb->len,
1245 					(u32)USB_CDC_NCM_NTB_MIN_OUT_SIZE);
1246 			else
1247 				ctx->tx_curr_size = USB_CDC_NCM_NTB_MIN_OUT_SIZE;
1248 			skb_out = alloc_skb(ctx->tx_curr_size, GFP_ATOMIC);
1249 
1250 			/* No allocation possible so we will abort */
1251 			if (skb_out == NULL) {
1252 				if (skb != NULL) {
1253 					dev_kfree_skb_any(skb);
1254 					dev->net->stats.tx_dropped++;
1255 				}
1256 				goto exit_no_skb;
1257 			}
1258 			ctx->tx_low_mem_val--;
1259 		}
1260 		if (ctx->is_ndp16) {
1261 			/* fill out the initial 16-bit NTB header */
1262 			nth.nth16 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth16));
1263 			nth.nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1264 			nth.nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1265 			nth.nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1266 		} else {
1267 			/* fill out the initial 32-bit NTB header */
1268 			nth.nth32 = skb_put_zero(skb_out, sizeof(struct usb_cdc_ncm_nth32));
1269 			nth.nth32->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH32_SIGN);
1270 			nth.nth32->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth32));
1271 			nth.nth32->wSequence = cpu_to_le16(ctx->tx_seq++);
1272 		}
1273 
1274 		/* count total number of frames in this NTB */
1275 		ctx->tx_curr_frame_num = 0;
1276 
1277 		/* recent payload counter for this skb_out */
1278 		ctx->tx_curr_frame_payload = 0;
1279 	}
1280 
1281 	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1282 		/* send any remaining skb first */
1283 		if (skb == NULL) {
1284 			skb = ctx->tx_rem_skb;
1285 			sign = ctx->tx_rem_sign;
1286 			ctx->tx_rem_skb = NULL;
1287 
1288 			/* check for end of skb */
1289 			if (skb == NULL)
1290 				break;
1291 		}
1292 
1293 		/* get the appropriate NDP for this skb */
1294 		if (ctx->is_ndp16)
1295 			ndp.ndp16 = cdc_ncm_ndp16(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1296 		else
1297 			ndp.ndp32 = cdc_ncm_ndp32(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1298 
1299 		/* align beginning of next frame */
1300 		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_curr_size);
1301 
1302 		/* check if we had enough room left for both NDP and frame */
1303 		if ((ctx->is_ndp16 && !ndp.ndp16) || (!ctx->is_ndp16 && !ndp.ndp32) ||
1304 		    skb_out->len + skb->len + delayed_ndp_size > ctx->tx_curr_size) {
1305 			if (n == 0) {
1306 				/* won't fit, MTU problem? */
1307 				dev_kfree_skb_any(skb);
1308 				skb = NULL;
1309 				dev->net->stats.tx_dropped++;
1310 			} else {
1311 				/* no room for skb - store for later */
1312 				if (ctx->tx_rem_skb != NULL) {
1313 					dev_kfree_skb_any(ctx->tx_rem_skb);
1314 					dev->net->stats.tx_dropped++;
1315 				}
1316 				ctx->tx_rem_skb = skb;
1317 				ctx->tx_rem_sign = sign;
1318 				skb = NULL;
1319 				ready2send = 1;
1320 				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1321 			}
1322 			break;
1323 		}
1324 
1325 		/* calculate frame number within this NDP */
1326 		if (ctx->is_ndp16) {
1327 			ndplen = le16_to_cpu(ndp.ndp16->wLength);
1328 			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1329 
1330 			/* OK, add this skb */
1331 			ndp.ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1332 			ndp.ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1333 			ndp.ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1334 		} else {
1335 			ndplen = le16_to_cpu(ndp.ndp32->wLength);
1336 			index = (ndplen - sizeof(struct usb_cdc_ncm_ndp32)) / sizeof(struct usb_cdc_ncm_dpe32) - 1;
1337 
1338 			ndp.ndp32->dpe32[index].dwDatagramLength = cpu_to_le32(skb->len);
1339 			ndp.ndp32->dpe32[index].dwDatagramIndex = cpu_to_le32(skb_out->len);
1340 			ndp.ndp32->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe32));
1341 		}
1342 		skb_put_data(skb_out, skb->data, skb->len);
1343 		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1344 		dev_kfree_skb_any(skb);
1345 		skb = NULL;
1346 
1347 		/* send now if this NDP is full */
1348 		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1349 			ready2send = 1;
1350 			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1351 			break;
1352 		}
1353 	}
1354 
1355 	/* free up any dangling skb */
1356 	if (skb != NULL) {
1357 		dev_kfree_skb_any(skb);
1358 		skb = NULL;
1359 		dev->net->stats.tx_dropped++;
1360 	}
1361 
1362 	ctx->tx_curr_frame_num = n;
1363 
1364 	if (n == 0) {
1365 		/* wait for more frames */
1366 		/* push variables */
1367 		ctx->tx_curr_skb = skb_out;
1368 		goto exit_no_skb;
1369 
1370 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1371 		/* wait for more frames */
1372 		/* push variables */
1373 		ctx->tx_curr_skb = skb_out;
1374 		/* set the pending count */
1375 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1376 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1377 		goto exit_no_skb;
1378 
1379 	} else {
1380 		if (n == ctx->tx_max_datagrams)
1381 			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1382 		/* frame goes out */
1383 		/* variables will be reset at next call */
1384 	}
1385 
1386 	/* If requested, put NDP at end of frame. */
1387 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1388 		if (ctx->is_ndp16) {
1389 			nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1390 			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1391 			nth.nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1392 			skb_put_data(skb_out, ctx->delayed_ndp16, ctx->max_ndp_size);
1393 
1394 			/* Zero out delayed NDP - signature checking will naturally fail. */
1395 			ndp.ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1396 		} else {
1397 			nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1398 			cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_curr_size - ctx->max_ndp_size);
1399 			nth.nth32->dwNdpIndex = cpu_to_le32(skb_out->len);
1400 			skb_put_data(skb_out, ctx->delayed_ndp32, ctx->max_ndp_size);
1401 
1402 			ndp.ndp32 = memset(ctx->delayed_ndp32, 0, ctx->max_ndp_size);
1403 		}
1404 	}
1405 
1406 	/* If collected data size is less or equal ctx->min_tx_pkt
1407 	 * bytes, we send buffers as it is. If we get more data, it
1408 	 * would be more efficient for USB HS mobile device with DMA
1409 	 * engine to receive a full size NTB, than canceling DMA
1410 	 * transfer and receiving a short packet.
1411 	 *
1412 	 * This optimization support is pointless if we end up sending
1413 	 * a ZLP after full sized NTBs.
1414 	 */
1415 	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1416 	    skb_out->len > ctx->min_tx_pkt) {
1417 		padding_count = ctx->tx_curr_size - skb_out->len;
1418 		if (!WARN_ON(padding_count > ctx->tx_curr_size))
1419 			skb_put_zero(skb_out, padding_count);
1420 	} else if (skb_out->len < ctx->tx_curr_size &&
1421 		   (skb_out->len % dev->maxpacket) == 0) {
1422 		skb_put_u8(skb_out, 0);	/* force short packet */
1423 	}
1424 
1425 	/* set final frame length */
1426 	if (ctx->is_ndp16) {
1427 		nth.nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1428 		nth.nth16->wBlockLength = cpu_to_le16(skb_out->len);
1429 	} else {
1430 		nth.nth32 = (struct usb_cdc_ncm_nth32 *)skb_out->data;
1431 		nth.nth32->dwBlockLength = cpu_to_le32(skb_out->len);
1432 	}
1433 
1434 	/* return skb */
1435 	ctx->tx_curr_skb = NULL;
1436 
1437 	/* keep private stats: framing overhead and number of NTBs */
1438 	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1439 	ctx->tx_ntbs++;
1440 
1441 	/* usbnet will count all the framing overhead by default.
1442 	 * Adjust the stats so that the tx_bytes counter show real
1443 	 * payload data instead.
1444 	 */
1445 	usbnet_set_skb_tx_stats(skb_out, n,
1446 				(long)ctx->tx_curr_frame_payload - skb_out->len);
1447 
1448 	return skb_out;
1449 
1450 exit_no_skb:
1451 	/* Start timer, if there is a remaining non-empty skb */
1452 	if (ctx->tx_curr_skb != NULL && n > 0)
1453 		cdc_ncm_tx_timeout_start(ctx);
1454 	return NULL;
1455 }
1456 EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1457 
1458 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1459 {
1460 	/* start timer, if not already started */
1461 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1462 		hrtimer_start(&ctx->tx_timer,
1463 				ctx->timer_interval,
1464 				HRTIMER_MODE_REL);
1465 }
1466 
1467 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1468 {
1469 	struct cdc_ncm_ctx *ctx =
1470 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1471 
1472 	if (!atomic_read(&ctx->stop))
1473 		tasklet_schedule(&ctx->bh);
1474 	return HRTIMER_NORESTART;
1475 }
1476 
1477 static void cdc_ncm_txpath_bh(struct tasklet_struct *t)
1478 {
1479 	struct cdc_ncm_ctx *ctx = from_tasklet(ctx, t, bh);
1480 	struct usbnet *dev = ctx->dev;
1481 
1482 	spin_lock_bh(&ctx->mtx);
1483 	if (ctx->tx_timer_pending != 0) {
1484 		ctx->tx_timer_pending--;
1485 		cdc_ncm_tx_timeout_start(ctx);
1486 		spin_unlock_bh(&ctx->mtx);
1487 	} else if (dev->net != NULL) {
1488 		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1489 		spin_unlock_bh(&ctx->mtx);
1490 		netif_tx_lock_bh(dev->net);
1491 		usbnet_start_xmit(NULL, dev->net);
1492 		netif_tx_unlock_bh(dev->net);
1493 	} else {
1494 		spin_unlock_bh(&ctx->mtx);
1495 	}
1496 }
1497 
1498 struct sk_buff *
1499 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1500 {
1501 	struct sk_buff *skb_out;
1502 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1503 
1504 	/*
1505 	 * The Ethernet API we are using does not support transmitting
1506 	 * multiple Ethernet frames in a single call. This driver will
1507 	 * accumulate multiple Ethernet frames and send out a larger
1508 	 * USB frame when the USB buffer is full or when a single jiffies
1509 	 * timeout happens.
1510 	 */
1511 	if (ctx == NULL)
1512 		goto error;
1513 
1514 	spin_lock_bh(&ctx->mtx);
1515 
1516 	if (ctx->is_ndp16)
1517 		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1518 	else
1519 		skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN));
1520 
1521 	spin_unlock_bh(&ctx->mtx);
1522 	return skb_out;
1523 
1524 error:
1525 	if (skb != NULL)
1526 		dev_kfree_skb_any(skb);
1527 
1528 	return NULL;
1529 }
1530 EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1531 
1532 /* verify NTB header and return offset of first NDP, or negative error */
1533 int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1534 {
1535 	struct usbnet *dev = netdev_priv(skb_in->dev);
1536 	struct usb_cdc_ncm_nth16 *nth16;
1537 	int len;
1538 	int ret = -EINVAL;
1539 
1540 	if (ctx == NULL)
1541 		goto error;
1542 
1543 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1544 					sizeof(struct usb_cdc_ncm_ndp16))) {
1545 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1546 		goto error;
1547 	}
1548 
1549 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1550 
1551 	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1552 		netif_dbg(dev, rx_err, dev->net,
1553 			  "invalid NTH16 signature <%#010x>\n",
1554 			  le32_to_cpu(nth16->dwSignature));
1555 		goto error;
1556 	}
1557 
1558 	len = le16_to_cpu(nth16->wBlockLength);
1559 	if (len > ctx->rx_max) {
1560 		netif_dbg(dev, rx_err, dev->net,
1561 			  "unsupported NTB block length %u/%u\n", len,
1562 			  ctx->rx_max);
1563 		goto error;
1564 	}
1565 
1566 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1567 	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1568 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1569 		netif_dbg(dev, rx_err, dev->net,
1570 			  "sequence number glitch prev=%d curr=%d\n",
1571 			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1572 	}
1573 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1574 
1575 	ret = le16_to_cpu(nth16->wNdpIndex);
1576 error:
1577 	return ret;
1578 }
1579 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1580 
1581 int cdc_ncm_rx_verify_nth32(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1582 {
1583 	struct usbnet *dev = netdev_priv(skb_in->dev);
1584 	struct usb_cdc_ncm_nth32 *nth32;
1585 	int len;
1586 	int ret = -EINVAL;
1587 
1588 	if (ctx == NULL)
1589 		goto error;
1590 
1591 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth32) +
1592 					sizeof(struct usb_cdc_ncm_ndp32))) {
1593 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1594 		goto error;
1595 	}
1596 
1597 	nth32 = (struct usb_cdc_ncm_nth32 *)skb_in->data;
1598 
1599 	if (nth32->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH32_SIGN)) {
1600 		netif_dbg(dev, rx_err, dev->net,
1601 			  "invalid NTH32 signature <%#010x>\n",
1602 			  le32_to_cpu(nth32->dwSignature));
1603 		goto error;
1604 	}
1605 
1606 	len = le32_to_cpu(nth32->dwBlockLength);
1607 	if (len > ctx->rx_max) {
1608 		netif_dbg(dev, rx_err, dev->net,
1609 			  "unsupported NTB block length %u/%u\n", len,
1610 			  ctx->rx_max);
1611 		goto error;
1612 	}
1613 
1614 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth32->wSequence) &&
1615 	    (ctx->rx_seq || le16_to_cpu(nth32->wSequence)) &&
1616 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth32->wSequence))) {
1617 		netif_dbg(dev, rx_err, dev->net,
1618 			  "sequence number glitch prev=%d curr=%d\n",
1619 			  ctx->rx_seq, le16_to_cpu(nth32->wSequence));
1620 	}
1621 	ctx->rx_seq = le16_to_cpu(nth32->wSequence);
1622 
1623 	ret = le32_to_cpu(nth32->dwNdpIndex);
1624 error:
1625 	return ret;
1626 }
1627 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth32);
1628 
1629 /* verify NDP header and return number of datagrams, or negative error */
1630 int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1631 {
1632 	struct usbnet *dev = netdev_priv(skb_in->dev);
1633 	struct usb_cdc_ncm_ndp16 *ndp16;
1634 	int ret = -EINVAL;
1635 
1636 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1637 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1638 			  ndpoffset);
1639 		goto error;
1640 	}
1641 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1642 
1643 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1644 		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1645 			  le16_to_cpu(ndp16->wLength));
1646 		goto error;
1647 	}
1648 
1649 	ret = ((le16_to_cpu(ndp16->wLength) -
1650 					sizeof(struct usb_cdc_ncm_ndp16)) /
1651 					sizeof(struct usb_cdc_ncm_dpe16));
1652 	ret--; /* we process NDP entries except for the last one */
1653 
1654 	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1655 	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1656 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1657 		ret = -EINVAL;
1658 	}
1659 
1660 error:
1661 	return ret;
1662 }
1663 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1664 
1665 /* verify NDP header and return number of datagrams, or negative error */
1666 int cdc_ncm_rx_verify_ndp32(struct sk_buff *skb_in, int ndpoffset)
1667 {
1668 	struct usbnet *dev = netdev_priv(skb_in->dev);
1669 	struct usb_cdc_ncm_ndp32 *ndp32;
1670 	int ret = -EINVAL;
1671 
1672 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp32)) > skb_in->len) {
1673 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1674 			  ndpoffset);
1675 		goto error;
1676 	}
1677 	ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1678 
1679 	if (le16_to_cpu(ndp32->wLength) < USB_CDC_NCM_NDP32_LENGTH_MIN) {
1680 		netif_dbg(dev, rx_err, dev->net, "invalid DPT32 length <%u>\n",
1681 			  le16_to_cpu(ndp32->wLength));
1682 		goto error;
1683 	}
1684 
1685 	ret = ((le16_to_cpu(ndp32->wLength) -
1686 					sizeof(struct usb_cdc_ncm_ndp32)) /
1687 					sizeof(struct usb_cdc_ncm_dpe32));
1688 	ret--; /* we process NDP entries except for the last one */
1689 
1690 	if ((sizeof(struct usb_cdc_ncm_ndp32) +
1691 	     ret * (sizeof(struct usb_cdc_ncm_dpe32))) > skb_in->len) {
1692 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1693 		ret = -EINVAL;
1694 	}
1695 
1696 error:
1697 	return ret;
1698 }
1699 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp32);
1700 
1701 int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1702 {
1703 	struct sk_buff *skb;
1704 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1705 	int len;
1706 	int nframes;
1707 	int x;
1708 	int offset;
1709 	union {
1710 		struct usb_cdc_ncm_ndp16 *ndp16;
1711 		struct usb_cdc_ncm_ndp32 *ndp32;
1712 	} ndp;
1713 	union {
1714 		struct usb_cdc_ncm_dpe16 *dpe16;
1715 		struct usb_cdc_ncm_dpe32 *dpe32;
1716 	} dpe;
1717 
1718 	int ndpoffset;
1719 	int loopcount = 50; /* arbitrary max preventing infinite loop */
1720 	u32 payload = 0;
1721 
1722 	if (ctx->is_ndp16)
1723 		ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1724 	else
1725 		ndpoffset = cdc_ncm_rx_verify_nth32(ctx, skb_in);
1726 
1727 	if (ndpoffset < 0)
1728 		goto error;
1729 
1730 next_ndp:
1731 	if (ctx->is_ndp16) {
1732 		nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1733 		if (nframes < 0)
1734 			goto error;
1735 
1736 		ndp.ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1737 
1738 		if (ndp.ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1739 			netif_dbg(dev, rx_err, dev->net,
1740 				  "invalid DPT16 signature <%#010x>\n",
1741 				  le32_to_cpu(ndp.ndp16->dwSignature));
1742 			goto err_ndp;
1743 		}
1744 		dpe.dpe16 = ndp.ndp16->dpe16;
1745 	} else {
1746 		nframes = cdc_ncm_rx_verify_ndp32(skb_in, ndpoffset);
1747 		if (nframes < 0)
1748 			goto error;
1749 
1750 		ndp.ndp32 = (struct usb_cdc_ncm_ndp32 *)(skb_in->data + ndpoffset);
1751 
1752 		if (ndp.ndp32->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP32_NOCRC_SIGN)) {
1753 			netif_dbg(dev, rx_err, dev->net,
1754 				  "invalid DPT32 signature <%#010x>\n",
1755 				  le32_to_cpu(ndp.ndp32->dwSignature));
1756 			goto err_ndp;
1757 		}
1758 		dpe.dpe32 = ndp.ndp32->dpe32;
1759 	}
1760 
1761 	for (x = 0; x < nframes; x++) {
1762 		if (ctx->is_ndp16) {
1763 			offset = le16_to_cpu(dpe.dpe16->wDatagramIndex);
1764 			len = le16_to_cpu(dpe.dpe16->wDatagramLength);
1765 		} else {
1766 			offset = le32_to_cpu(dpe.dpe32->dwDatagramIndex);
1767 			len = le32_to_cpu(dpe.dpe32->dwDatagramLength);
1768 		}
1769 
1770 		/*
1771 		 * CDC NCM ch. 3.7
1772 		 * All entries after first NULL entry are to be ignored
1773 		 */
1774 		if ((offset == 0) || (len == 0)) {
1775 			if (!x)
1776 				goto err_ndp; /* empty NTB */
1777 			break;
1778 		}
1779 
1780 		/* sanity checking */
1781 		if (((offset + len) > skb_in->len) ||
1782 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1783 			netif_dbg(dev, rx_err, dev->net,
1784 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1785 				  x, offset, len, skb_in);
1786 			if (!x)
1787 				goto err_ndp;
1788 			break;
1789 
1790 		} else {
1791 			/* create a fresh copy to reduce truesize */
1792 			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1793 			if (!skb)
1794 				goto error;
1795 			skb_put_data(skb, skb_in->data + offset, len);
1796 			usbnet_skb_return(dev, skb);
1797 			payload += len;	/* count payload bytes in this NTB */
1798 		}
1799 
1800 		if (ctx->is_ndp16)
1801 			dpe.dpe16++;
1802 		else
1803 			dpe.dpe32++;
1804 	}
1805 err_ndp:
1806 	/* are there more NDPs to process? */
1807 	if (ctx->is_ndp16)
1808 		ndpoffset = le16_to_cpu(ndp.ndp16->wNextNdpIndex);
1809 	else
1810 		ndpoffset = le32_to_cpu(ndp.ndp32->dwNextNdpIndex);
1811 
1812 	if (ndpoffset && loopcount--)
1813 		goto next_ndp;
1814 
1815 	/* update stats */
1816 	ctx->rx_overhead += skb_in->len - payload;
1817 	ctx->rx_ntbs++;
1818 
1819 	return 1;
1820 error:
1821 	return 0;
1822 }
1823 EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1824 
1825 static void
1826 cdc_ncm_speed_change(struct usbnet *dev,
1827 		     struct usb_cdc_speed_change *data)
1828 {
1829 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1830 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1831 
1832 	/* if the speed hasn't changed, don't report it.
1833 	 * RTL8156 shipped before 2021 sends notification about every 32ms.
1834 	 */
1835 	if (dev->rx_speed == rx_speed && dev->tx_speed == tx_speed)
1836 		return;
1837 
1838 	dev->rx_speed = rx_speed;
1839 	dev->tx_speed = tx_speed;
1840 
1841 	/*
1842 	 * Currently the USB-NET API does not support reporting the actual
1843 	 * device speed. Do print it instead.
1844 	 */
1845 	if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1846 		netif_info(dev, link, dev->net,
1847 			   "%u mbit/s downlink %u mbit/s uplink\n",
1848 			   (unsigned int)(rx_speed / 1000000U),
1849 			   (unsigned int)(tx_speed / 1000000U));
1850 	} else {
1851 		netif_info(dev, link, dev->net,
1852 			   "%u kbit/s downlink %u kbit/s uplink\n",
1853 			   (unsigned int)(rx_speed / 1000U),
1854 			   (unsigned int)(tx_speed / 1000U));
1855 	}
1856 }
1857 
1858 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1859 {
1860 	struct usb_cdc_notification *event;
1861 
1862 	if (urb->actual_length < sizeof(*event))
1863 		return;
1864 
1865 	/* test for split data in 8-byte chunks */
1866 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1867 		cdc_ncm_speed_change(dev,
1868 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1869 		return;
1870 	}
1871 
1872 	event = urb->transfer_buffer;
1873 
1874 	switch (event->bNotificationType) {
1875 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1876 		/*
1877 		 * According to the CDC NCM specification ch.7.1
1878 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1879 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
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",
1904 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1905 			| FLAG_LINK_INTR,
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_WWAN */
1916 static const struct driver_info wwan_info = {
1917 	.description = "Mobile Broadband Network Device",
1918 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1919 			| FLAG_LINK_INTR | FLAG_WWAN,
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 wwan_info, but with FLAG_NOARP  */
1930 static const struct driver_info wwan_noarp_info = {
1931 	.description = "Mobile Broadband Network Device (NO ARP)",
1932 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1933 			| FLAG_LINK_INTR | FLAG_WWAN | FLAG_NOARP,
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 static const struct usb_device_id cdc_devs[] = {
1944 	/* Ericsson MBM devices like F5521gw */
1945 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1946 		| USB_DEVICE_ID_MATCH_VENDOR,
1947 	  .idVendor = 0x0bdb,
1948 	  .bInterfaceClass = USB_CLASS_COMM,
1949 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1950 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1951 	  .driver_info = (unsigned long) &wwan_info,
1952 	},
1953 
1954 	/* Telit LE910 V2 */
1955 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1bc7, 0x0036,
1956 		USB_CLASS_COMM,
1957 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1958 	  .driver_info = (unsigned long)&wwan_noarp_info,
1959 	},
1960 
1961 	/* DW5812 LTE Verizon Mobile Broadband Card
1962 	 * Unlike DW5550 this device requires FLAG_NOARP
1963 	 */
1964 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bb,
1965 		USB_CLASS_COMM,
1966 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1967 	  .driver_info = (unsigned long)&wwan_noarp_info,
1968 	},
1969 
1970 	/* DW5813 LTE AT&T Mobile Broadband Card
1971 	 * Unlike DW5550 this device requires FLAG_NOARP
1972 	 */
1973 	{ USB_DEVICE_AND_INTERFACE_INFO(0x413c, 0x81bc,
1974 		USB_CLASS_COMM,
1975 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1976 	  .driver_info = (unsigned long)&wwan_noarp_info,
1977 	},
1978 
1979 	/* Dell branded MBM devices like DW5550 */
1980 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1981 		| USB_DEVICE_ID_MATCH_VENDOR,
1982 	  .idVendor = 0x413c,
1983 	  .bInterfaceClass = USB_CLASS_COMM,
1984 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1985 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1986 	  .driver_info = (unsigned long) &wwan_info,
1987 	},
1988 
1989 	/* Toshiba branded MBM devices */
1990 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1991 		| USB_DEVICE_ID_MATCH_VENDOR,
1992 	  .idVendor = 0x0930,
1993 	  .bInterfaceClass = USB_CLASS_COMM,
1994 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1995 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1996 	  .driver_info = (unsigned long) &wwan_info,
1997 	},
1998 
1999 	/* tag Huawei devices as wwan */
2000 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
2001 					USB_CLASS_COMM,
2002 					USB_CDC_SUBCLASS_NCM,
2003 					USB_CDC_PROTO_NONE),
2004 	  .driver_info = (unsigned long)&wwan_info,
2005 	},
2006 
2007 	/* Infineon(now Intel) HSPA Modem platform */
2008 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
2009 		USB_CLASS_COMM,
2010 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2011 	  .driver_info = (unsigned long)&wwan_noarp_info,
2012 	},
2013 
2014 	/* u-blox TOBY-L4 */
2015 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1546, 0x1010,
2016 		USB_CLASS_COMM,
2017 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2018 	  .driver_info = (unsigned long)&wwan_info,
2019 	},
2020 
2021 	/* Generic CDC-NCM devices */
2022 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
2023 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
2024 		.driver_info = (unsigned long)&cdc_ncm_info,
2025 	},
2026 	{
2027 	},
2028 };
2029 MODULE_DEVICE_TABLE(usb, cdc_devs);
2030 
2031 static struct usb_driver cdc_ncm_driver = {
2032 	.name = "cdc_ncm",
2033 	.id_table = cdc_devs,
2034 	.probe = usbnet_probe,
2035 	.disconnect = usbnet_disconnect,
2036 	.suspend = usbnet_suspend,
2037 	.resume = usbnet_resume,
2038 	.reset_resume =	usbnet_resume,
2039 	.supports_autosuspend = 1,
2040 	.disable_hub_initiated_lpm = 1,
2041 };
2042 
2043 module_usb_driver(cdc_ncm_driver);
2044 
2045 MODULE_AUTHOR("Hans Petter Selasky");
2046 MODULE_DESCRIPTION("USB CDC NCM host driver");
2047 MODULE_LICENSE("Dual BSD/GPL");
2048