xref: /openbmc/linux/drivers/net/usb/cdc_ncm.c (revision eb3fcf00)
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/ethtool.h>
45 #include <linux/workqueue.h>
46 #include <linux/mii.h>
47 #include <linux/crc32.h>
48 #include <linux/usb.h>
49 #include <linux/hrtimer.h>
50 #include <linux/atomic.h>
51 #include <linux/usb/usbnet.h>
52 #include <linux/usb/cdc.h>
53 #include <linux/usb/cdc_ncm.h>
54 
55 #if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
56 static bool prefer_mbim = true;
57 #else
58 static bool prefer_mbim;
59 #endif
60 module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
61 MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");
62 
63 static void cdc_ncm_txpath_bh(unsigned long param);
64 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
65 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
66 static struct usb_driver cdc_ncm_driver;
67 
68 struct cdc_ncm_stats {
69 	char stat_string[ETH_GSTRING_LEN];
70 	int sizeof_stat;
71 	int stat_offset;
72 };
73 
74 #define CDC_NCM_STAT(str, m) { \
75 		.stat_string = str, \
76 		.sizeof_stat = sizeof(((struct cdc_ncm_ctx *)0)->m), \
77 		.stat_offset = offsetof(struct cdc_ncm_ctx, m) }
78 #define CDC_NCM_SIMPLE_STAT(m)	CDC_NCM_STAT(__stringify(m), m)
79 
80 static const struct cdc_ncm_stats cdc_ncm_gstrings_stats[] = {
81 	CDC_NCM_SIMPLE_STAT(tx_reason_ntb_full),
82 	CDC_NCM_SIMPLE_STAT(tx_reason_ndp_full),
83 	CDC_NCM_SIMPLE_STAT(tx_reason_timeout),
84 	CDC_NCM_SIMPLE_STAT(tx_reason_max_datagram),
85 	CDC_NCM_SIMPLE_STAT(tx_overhead),
86 	CDC_NCM_SIMPLE_STAT(tx_ntbs),
87 	CDC_NCM_SIMPLE_STAT(rx_overhead),
88 	CDC_NCM_SIMPLE_STAT(rx_ntbs),
89 };
90 
91 static int cdc_ncm_get_sset_count(struct net_device __always_unused *netdev, int sset)
92 {
93 	switch (sset) {
94 	case ETH_SS_STATS:
95 		return ARRAY_SIZE(cdc_ncm_gstrings_stats);
96 	default:
97 		return -EOPNOTSUPP;
98 	}
99 }
100 
101 static void cdc_ncm_get_ethtool_stats(struct net_device *netdev,
102 				    struct ethtool_stats __always_unused *stats,
103 				    u64 *data)
104 {
105 	struct usbnet *dev = netdev_priv(netdev);
106 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
107 	int i;
108 	char *p = NULL;
109 
110 	for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
111 		p = (char *)ctx + cdc_ncm_gstrings_stats[i].stat_offset;
112 		data[i] = (cdc_ncm_gstrings_stats[i].sizeof_stat == sizeof(u64)) ? *(u64 *)p : *(u32 *)p;
113 	}
114 }
115 
116 static void cdc_ncm_get_strings(struct net_device __always_unused *netdev, u32 stringset, u8 *data)
117 {
118 	u8 *p = data;
119 	int i;
120 
121 	switch (stringset) {
122 	case ETH_SS_STATS:
123 		for (i = 0; i < ARRAY_SIZE(cdc_ncm_gstrings_stats); i++) {
124 			memcpy(p, cdc_ncm_gstrings_stats[i].stat_string, ETH_GSTRING_LEN);
125 			p += ETH_GSTRING_LEN;
126 		}
127 	}
128 }
129 
130 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx);
131 
132 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
133 	.get_settings      = usbnet_get_settings,
134 	.set_settings      = usbnet_set_settings,
135 	.get_link          = usbnet_get_link,
136 	.nway_reset        = usbnet_nway_reset,
137 	.get_drvinfo       = usbnet_get_drvinfo,
138 	.get_msglevel      = usbnet_get_msglevel,
139 	.set_msglevel      = usbnet_set_msglevel,
140 	.get_ts_info       = ethtool_op_get_ts_info,
141 	.get_sset_count    = cdc_ncm_get_sset_count,
142 	.get_strings       = cdc_ncm_get_strings,
143 	.get_ethtool_stats = cdc_ncm_get_ethtool_stats,
144 };
145 
146 static u32 cdc_ncm_check_rx_max(struct usbnet *dev, u32 new_rx)
147 {
148 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
149 	u32 val, max, min;
150 
151 	/* clamp new_rx to sane values */
152 	min = USB_CDC_NCM_NTB_MIN_IN_SIZE;
153 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_RX, le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
154 
155 	/* dwNtbInMaxSize spec violation? Use MIN size for both limits */
156 	if (max < min) {
157 		dev_warn(&dev->intf->dev, "dwNtbInMaxSize=%u is too small. Using %u\n",
158 			 le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize), min);
159 		max = min;
160 	}
161 
162 	val = clamp_t(u32, new_rx, min, max);
163 	if (val != new_rx)
164 		dev_dbg(&dev->intf->dev, "rx_max must be in the [%u, %u] range\n", min, max);
165 
166 	return val;
167 }
168 
169 static u32 cdc_ncm_check_tx_max(struct usbnet *dev, u32 new_tx)
170 {
171 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
172 	u32 val, max, min;
173 
174 	/* clamp new_tx to sane values */
175 	min = ctx->max_datagram_size + ctx->max_ndp_size + sizeof(struct usb_cdc_ncm_nth16);
176 	max = min_t(u32, CDC_NCM_NTB_MAX_SIZE_TX, le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
177 
178 	/* some devices set dwNtbOutMaxSize too low for the above default */
179 	min = min(min, max);
180 
181 	val = clamp_t(u32, new_tx, min, max);
182 	if (val != new_tx)
183 		dev_dbg(&dev->intf->dev, "tx_max must be in the [%u, %u] range\n", min, max);
184 
185 	return val;
186 }
187 
188 static ssize_t cdc_ncm_show_min_tx_pkt(struct device *d, struct device_attribute *attr, char *buf)
189 {
190 	struct usbnet *dev = netdev_priv(to_net_dev(d));
191 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
192 
193 	return sprintf(buf, "%u\n", ctx->min_tx_pkt);
194 }
195 
196 static ssize_t cdc_ncm_show_rx_max(struct device *d, struct device_attribute *attr, char *buf)
197 {
198 	struct usbnet *dev = netdev_priv(to_net_dev(d));
199 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
200 
201 	return sprintf(buf, "%u\n", ctx->rx_max);
202 }
203 
204 static ssize_t cdc_ncm_show_tx_max(struct device *d, struct device_attribute *attr, char *buf)
205 {
206 	struct usbnet *dev = netdev_priv(to_net_dev(d));
207 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
208 
209 	return sprintf(buf, "%u\n", ctx->tx_max);
210 }
211 
212 static ssize_t cdc_ncm_show_tx_timer_usecs(struct device *d, struct device_attribute *attr, char *buf)
213 {
214 	struct usbnet *dev = netdev_priv(to_net_dev(d));
215 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
216 
217 	return sprintf(buf, "%u\n", ctx->timer_interval / (u32)NSEC_PER_USEC);
218 }
219 
220 static ssize_t cdc_ncm_store_min_tx_pkt(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
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 	unsigned long val;
225 
226 	/* no need to restrict values - anything from 0 to infinity is OK */
227 	if (kstrtoul(buf, 0, &val))
228 		return -EINVAL;
229 
230 	ctx->min_tx_pkt = val;
231 	return len;
232 }
233 
234 static ssize_t cdc_ncm_store_rx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
235 {
236 	struct usbnet *dev = netdev_priv(to_net_dev(d));
237 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
238 	unsigned long val;
239 
240 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_rx_max(dev, val) != val)
241 		return -EINVAL;
242 
243 	cdc_ncm_update_rxtx_max(dev, val, ctx->tx_max);
244 	return len;
245 }
246 
247 static ssize_t cdc_ncm_store_tx_max(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
248 {
249 	struct usbnet *dev = netdev_priv(to_net_dev(d));
250 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
251 	unsigned long val;
252 
253 	if (kstrtoul(buf, 0, &val) || cdc_ncm_check_tx_max(dev, val) != val)
254 		return -EINVAL;
255 
256 	cdc_ncm_update_rxtx_max(dev, ctx->rx_max, val);
257 	return len;
258 }
259 
260 static ssize_t cdc_ncm_store_tx_timer_usecs(struct device *d,  struct device_attribute *attr, const char *buf, size_t len)
261 {
262 	struct usbnet *dev = netdev_priv(to_net_dev(d));
263 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
264 	ssize_t ret;
265 	unsigned long val;
266 
267 	ret = kstrtoul(buf, 0, &val);
268 	if (ret)
269 		return ret;
270 	if (val && (val < CDC_NCM_TIMER_INTERVAL_MIN || val > CDC_NCM_TIMER_INTERVAL_MAX))
271 		return -EINVAL;
272 
273 	spin_lock_bh(&ctx->mtx);
274 	ctx->timer_interval = val * NSEC_PER_USEC;
275 	if (!ctx->timer_interval)
276 		ctx->tx_timer_pending = 0;
277 	spin_unlock_bh(&ctx->mtx);
278 	return len;
279 }
280 
281 static DEVICE_ATTR(min_tx_pkt, S_IRUGO | S_IWUSR, cdc_ncm_show_min_tx_pkt, cdc_ncm_store_min_tx_pkt);
282 static DEVICE_ATTR(rx_max, S_IRUGO | S_IWUSR, cdc_ncm_show_rx_max, cdc_ncm_store_rx_max);
283 static DEVICE_ATTR(tx_max, S_IRUGO | S_IWUSR, cdc_ncm_show_tx_max, cdc_ncm_store_tx_max);
284 static DEVICE_ATTR(tx_timer_usecs, S_IRUGO | S_IWUSR, cdc_ncm_show_tx_timer_usecs, cdc_ncm_store_tx_timer_usecs);
285 
286 #define NCM_PARM_ATTR(name, format, tocpu)				\
287 static ssize_t cdc_ncm_show_##name(struct device *d, struct device_attribute *attr, char *buf) \
288 { \
289 	struct usbnet *dev = netdev_priv(to_net_dev(d)); \
290 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; \
291 	return sprintf(buf, format "\n", tocpu(ctx->ncm_parm.name));	\
292 } \
293 static DEVICE_ATTR(name, S_IRUGO, cdc_ncm_show_##name, NULL)
294 
295 NCM_PARM_ATTR(bmNtbFormatsSupported, "0x%04x", le16_to_cpu);
296 NCM_PARM_ATTR(dwNtbInMaxSize, "%u", le32_to_cpu);
297 NCM_PARM_ATTR(wNdpInDivisor, "%u", le16_to_cpu);
298 NCM_PARM_ATTR(wNdpInPayloadRemainder, "%u", le16_to_cpu);
299 NCM_PARM_ATTR(wNdpInAlignment, "%u", le16_to_cpu);
300 NCM_PARM_ATTR(dwNtbOutMaxSize, "%u", le32_to_cpu);
301 NCM_PARM_ATTR(wNdpOutDivisor, "%u", le16_to_cpu);
302 NCM_PARM_ATTR(wNdpOutPayloadRemainder, "%u", le16_to_cpu);
303 NCM_PARM_ATTR(wNdpOutAlignment, "%u", le16_to_cpu);
304 NCM_PARM_ATTR(wNtbOutMaxDatagrams, "%u", le16_to_cpu);
305 
306 static struct attribute *cdc_ncm_sysfs_attrs[] = {
307 	&dev_attr_min_tx_pkt.attr,
308 	&dev_attr_rx_max.attr,
309 	&dev_attr_tx_max.attr,
310 	&dev_attr_tx_timer_usecs.attr,
311 	&dev_attr_bmNtbFormatsSupported.attr,
312 	&dev_attr_dwNtbInMaxSize.attr,
313 	&dev_attr_wNdpInDivisor.attr,
314 	&dev_attr_wNdpInPayloadRemainder.attr,
315 	&dev_attr_wNdpInAlignment.attr,
316 	&dev_attr_dwNtbOutMaxSize.attr,
317 	&dev_attr_wNdpOutDivisor.attr,
318 	&dev_attr_wNdpOutPayloadRemainder.attr,
319 	&dev_attr_wNdpOutAlignment.attr,
320 	&dev_attr_wNtbOutMaxDatagrams.attr,
321 	NULL,
322 };
323 
324 static struct attribute_group cdc_ncm_sysfs_attr_group = {
325 	.name = "cdc_ncm",
326 	.attrs = cdc_ncm_sysfs_attrs,
327 };
328 
329 /* handle rx_max and tx_max changes */
330 static void cdc_ncm_update_rxtx_max(struct usbnet *dev, u32 new_rx, u32 new_tx)
331 {
332 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
333 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
334 	u32 val;
335 
336 	val = cdc_ncm_check_rx_max(dev, new_rx);
337 
338 	/* inform device about NTB input size changes */
339 	if (val != ctx->rx_max) {
340 		__le32 dwNtbInMaxSize = cpu_to_le32(val);
341 
342 		dev_info(&dev->intf->dev, "setting rx_max = %u\n", val);
343 
344 		/* tell device to use new size */
345 		if (usbnet_write_cmd(dev, USB_CDC_SET_NTB_INPUT_SIZE,
346 				     USB_TYPE_CLASS | USB_DIR_OUT
347 				     | USB_RECIP_INTERFACE,
348 				     0, iface_no, &dwNtbInMaxSize, 4) < 0)
349 			dev_dbg(&dev->intf->dev, "Setting NTB Input Size failed\n");
350 		else
351 			ctx->rx_max = val;
352 	}
353 
354 	/* usbnet use these values for sizing rx queues */
355 	if (dev->rx_urb_size != ctx->rx_max) {
356 		dev->rx_urb_size = ctx->rx_max;
357 		if (netif_running(dev->net))
358 			usbnet_unlink_rx_urbs(dev);
359 	}
360 
361 	val = cdc_ncm_check_tx_max(dev, new_tx);
362 	if (val != ctx->tx_max)
363 		dev_info(&dev->intf->dev, "setting tx_max = %u\n", val);
364 
365 	/* Adding a pad byte here if necessary simplifies the handling
366 	 * in cdc_ncm_fill_tx_frame, making tx_max always represent
367 	 * the real skb max size.
368 	 *
369 	 * We cannot use dev->maxpacket here because this is called from
370 	 * .bind which is called before usbnet sets up dev->maxpacket
371 	 */
372 	if (val != le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize) &&
373 	    val % usb_maxpacket(dev->udev, dev->out, 1) == 0)
374 		val++;
375 
376 	/* we might need to flush any pending tx buffers if running */
377 	if (netif_running(dev->net) && val > ctx->tx_max) {
378 		netif_tx_lock_bh(dev->net);
379 		usbnet_start_xmit(NULL, dev->net);
380 		/* make sure tx_curr_skb is reallocated if it was empty */
381 		if (ctx->tx_curr_skb) {
382 			dev_kfree_skb_any(ctx->tx_curr_skb);
383 			ctx->tx_curr_skb = NULL;
384 		}
385 		ctx->tx_max = val;
386 		netif_tx_unlock_bh(dev->net);
387 	} else {
388 		ctx->tx_max = val;
389 	}
390 
391 	dev->hard_mtu = ctx->tx_max;
392 
393 	/* max qlen depend on hard_mtu and rx_urb_size */
394 	usbnet_update_max_qlen(dev);
395 
396 	/* never pad more than 3 full USB packets per transfer */
397 	ctx->min_tx_pkt = clamp_t(u16, ctx->tx_max - 3 * usb_maxpacket(dev->udev, dev->out, 1),
398 				  CDC_NCM_MIN_TX_PKT, ctx->tx_max);
399 }
400 
401 /* helpers for NCM and MBIM differences */
402 static u8 cdc_ncm_flags(struct usbnet *dev)
403 {
404 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
405 
406 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
407 		return ctx->mbim_desc->bmNetworkCapabilities;
408 	if (ctx->func_desc)
409 		return ctx->func_desc->bmNetworkCapabilities;
410 	return 0;
411 }
412 
413 static int cdc_ncm_eth_hlen(struct usbnet *dev)
414 {
415 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
416 		return 0;
417 	return ETH_HLEN;
418 }
419 
420 static u32 cdc_ncm_min_dgram_size(struct usbnet *dev)
421 {
422 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting))
423 		return CDC_MBIM_MIN_DATAGRAM_SIZE;
424 	return CDC_NCM_MIN_DATAGRAM_SIZE;
425 }
426 
427 static u32 cdc_ncm_max_dgram_size(struct usbnet *dev)
428 {
429 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
430 
431 	if (cdc_ncm_comm_intf_is_mbim(dev->intf->cur_altsetting) && ctx->mbim_desc)
432 		return le16_to_cpu(ctx->mbim_desc->wMaxSegmentSize);
433 	if (ctx->ether_desc)
434 		return le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
435 	return CDC_NCM_MAX_DATAGRAM_SIZE;
436 }
437 
438 /* initial one-time device setup.  MUST be called with the data interface
439  * in altsetting 0
440  */
441 static int cdc_ncm_init(struct usbnet *dev)
442 {
443 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
444 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
445 	int err;
446 
447 	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
448 			      USB_TYPE_CLASS | USB_DIR_IN
449 			      |USB_RECIP_INTERFACE,
450 			      0, iface_no, &ctx->ncm_parm,
451 			      sizeof(ctx->ncm_parm));
452 	if (err < 0) {
453 		dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
454 		return err; /* GET_NTB_PARAMETERS is required */
455 	}
456 
457 	/* set CRC Mode */
458 	if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
459 		dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
460 		err = usbnet_write_cmd(dev, USB_CDC_SET_CRC_MODE,
461 				       USB_TYPE_CLASS | USB_DIR_OUT
462 				       | USB_RECIP_INTERFACE,
463 				       USB_CDC_NCM_CRC_NOT_APPENDED,
464 				       iface_no, NULL, 0);
465 		if (err < 0)
466 			dev_err(&dev->intf->dev, "SET_CRC_MODE failed\n");
467 	}
468 
469 	/* set NTB format, if both formats are supported.
470 	 *
471 	 * "The host shall only send this command while the NCM Data
472 	 *  Interface is in alternate setting 0."
473 	 */
474 	if (le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported) &
475 						USB_CDC_NCM_NTB32_SUPPORTED) {
476 		dev_dbg(&dev->intf->dev, "Setting NTB format to 16-bit\n");
477 		err = usbnet_write_cmd(dev, USB_CDC_SET_NTB_FORMAT,
478 				       USB_TYPE_CLASS | USB_DIR_OUT
479 				       | USB_RECIP_INTERFACE,
480 				       USB_CDC_NCM_NTB16_FORMAT,
481 				       iface_no, NULL, 0);
482 		if (err < 0)
483 			dev_err(&dev->intf->dev, "SET_NTB_FORMAT failed\n");
484 	}
485 
486 	/* set initial device values */
487 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
488 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
489 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
490 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
491 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
492 	/* devices prior to NCM Errata shall set this field to zero */
493 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
494 
495 	dev_dbg(&dev->intf->dev,
496 		"dwNtbInMaxSize=%u dwNtbOutMaxSize=%u wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
497 		ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
498 		ctx->tx_ndp_modulus, ctx->tx_max_datagrams, cdc_ncm_flags(dev));
499 
500 	/* max count of tx datagrams */
501 	if ((ctx->tx_max_datagrams == 0) ||
502 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
503 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
504 
505 	/* set up maximum NDP size */
506 	ctx->max_ndp_size = sizeof(struct usb_cdc_ncm_ndp16) + (ctx->tx_max_datagrams + 1) * sizeof(struct usb_cdc_ncm_dpe16);
507 
508 	/* initial coalescing timer interval */
509 	ctx->timer_interval = CDC_NCM_TIMER_INTERVAL_USEC * NSEC_PER_USEC;
510 
511 	return 0;
512 }
513 
514 /* set a new max datagram size */
515 static void cdc_ncm_set_dgram_size(struct usbnet *dev, int new_size)
516 {
517 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
518 	u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
519 	__le16 max_datagram_size;
520 	u16 mbim_mtu;
521 	int err;
522 
523 	/* set default based on descriptors */
524 	ctx->max_datagram_size = clamp_t(u32, new_size,
525 					 cdc_ncm_min_dgram_size(dev),
526 					 CDC_NCM_MAX_DATAGRAM_SIZE);
527 
528 	/* inform the device about the selected Max Datagram Size? */
529 	if (!(cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE))
530 		goto out;
531 
532 	/* read current mtu value from device */
533 	err = usbnet_read_cmd(dev, USB_CDC_GET_MAX_DATAGRAM_SIZE,
534 			      USB_TYPE_CLASS | USB_DIR_IN | USB_RECIP_INTERFACE,
535 			      0, iface_no, &max_datagram_size, 2);
536 	if (err < 0) {
537 		dev_dbg(&dev->intf->dev, "GET_MAX_DATAGRAM_SIZE failed\n");
538 		goto out;
539 	}
540 
541 	if (le16_to_cpu(max_datagram_size) == ctx->max_datagram_size)
542 		goto out;
543 
544 	max_datagram_size = cpu_to_le16(ctx->max_datagram_size);
545 	err = usbnet_write_cmd(dev, USB_CDC_SET_MAX_DATAGRAM_SIZE,
546 			       USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE,
547 			       0, iface_no, &max_datagram_size, 2);
548 	if (err < 0)
549 		dev_dbg(&dev->intf->dev, "SET_MAX_DATAGRAM_SIZE failed\n");
550 
551 out:
552 	/* set MTU to max supported by the device if necessary */
553 	dev->net->mtu = min_t(int, dev->net->mtu, ctx->max_datagram_size - cdc_ncm_eth_hlen(dev));
554 
555 	/* do not exceed operater preferred MTU */
556 	if (ctx->mbim_extended_desc) {
557 		mbim_mtu = le16_to_cpu(ctx->mbim_extended_desc->wMTU);
558 		if (mbim_mtu != 0 && mbim_mtu < dev->net->mtu)
559 			dev->net->mtu = mbim_mtu;
560 	}
561 }
562 
563 static void cdc_ncm_fix_modulus(struct usbnet *dev)
564 {
565 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
566 	u32 val;
567 
568 	/*
569 	 * verify that the structure alignment is:
570 	 * - power of two
571 	 * - not greater than the maximum transmit length
572 	 * - not less than four bytes
573 	 */
574 	val = ctx->tx_ndp_modulus;
575 
576 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
577 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
578 		dev_dbg(&dev->intf->dev, "Using default alignment: 4 bytes\n");
579 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
580 	}
581 
582 	/*
583 	 * verify that the payload alignment is:
584 	 * - power of two
585 	 * - not greater than the maximum transmit length
586 	 * - not less than four bytes
587 	 */
588 	val = ctx->tx_modulus;
589 
590 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
591 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
592 		dev_dbg(&dev->intf->dev, "Using default transmit modulus: 4 bytes\n");
593 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
594 	}
595 
596 	/* verify the payload remainder */
597 	if (ctx->tx_remainder >= ctx->tx_modulus) {
598 		dev_dbg(&dev->intf->dev, "Using default transmit remainder: 0 bytes\n");
599 		ctx->tx_remainder = 0;
600 	}
601 
602 	/* adjust TX-remainder according to NCM specification. */
603 	ctx->tx_remainder = ((ctx->tx_remainder - cdc_ncm_eth_hlen(dev)) &
604 			     (ctx->tx_modulus - 1));
605 }
606 
607 static int cdc_ncm_setup(struct usbnet *dev)
608 {
609 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
610 	u32 def_rx, def_tx;
611 
612 	/* be conservative when selecting intial buffer size to
613 	 * increase the number of hosts this will work for
614 	 */
615 	def_rx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_RX,
616 		       le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize));
617 	def_tx = min_t(u32, CDC_NCM_NTB_DEF_SIZE_TX,
618 		       le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize));
619 
620 	/* clamp rx_max and tx_max and inform device */
621 	cdc_ncm_update_rxtx_max(dev, def_rx, def_tx);
622 
623 	/* sanitize the modulus and remainder values */
624 	cdc_ncm_fix_modulus(dev);
625 
626 	/* set max datagram size */
627 	cdc_ncm_set_dgram_size(dev, cdc_ncm_max_dgram_size(dev));
628 	return 0;
629 }
630 
631 static void
632 cdc_ncm_find_endpoints(struct usbnet *dev, struct usb_interface *intf)
633 {
634 	struct usb_host_endpoint *e, *in = NULL, *out = NULL;
635 	u8 ep;
636 
637 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
638 
639 		e = intf->cur_altsetting->endpoint + ep;
640 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
641 		case USB_ENDPOINT_XFER_INT:
642 			if (usb_endpoint_dir_in(&e->desc)) {
643 				if (!dev->status)
644 					dev->status = e;
645 			}
646 			break;
647 
648 		case USB_ENDPOINT_XFER_BULK:
649 			if (usb_endpoint_dir_in(&e->desc)) {
650 				if (!in)
651 					in = e;
652 			} else {
653 				if (!out)
654 					out = e;
655 			}
656 			break;
657 
658 		default:
659 			break;
660 		}
661 	}
662 	if (in && !dev->in)
663 		dev->in = usb_rcvbulkpipe(dev->udev,
664 					  in->desc.bEndpointAddress &
665 					  USB_ENDPOINT_NUMBER_MASK);
666 	if (out && !dev->out)
667 		dev->out = usb_sndbulkpipe(dev->udev,
668 					   out->desc.bEndpointAddress &
669 					   USB_ENDPOINT_NUMBER_MASK);
670 }
671 
672 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
673 {
674 	if (ctx == NULL)
675 		return;
676 
677 	if (ctx->tx_rem_skb != NULL) {
678 		dev_kfree_skb_any(ctx->tx_rem_skb);
679 		ctx->tx_rem_skb = NULL;
680 	}
681 
682 	if (ctx->tx_curr_skb != NULL) {
683 		dev_kfree_skb_any(ctx->tx_curr_skb);
684 		ctx->tx_curr_skb = NULL;
685 	}
686 
687 	kfree(ctx->delayed_ndp16);
688 
689 	kfree(ctx);
690 }
691 
692 int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_altsetting, int drvflags)
693 {
694 	const struct usb_cdc_union_desc *union_desc = NULL;
695 	struct cdc_ncm_ctx *ctx;
696 	struct usb_driver *driver;
697 	u8 *buf;
698 	int len;
699 	int temp;
700 	u8 iface_no;
701 
702 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
703 	if (!ctx)
704 		return -ENOMEM;
705 
706 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
707 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
708 	ctx->bh.data = (unsigned long)dev;
709 	ctx->bh.func = cdc_ncm_txpath_bh;
710 	atomic_set(&ctx->stop, 0);
711 	spin_lock_init(&ctx->mtx);
712 
713 	/* store ctx pointer in device data field */
714 	dev->data[0] = (unsigned long)ctx;
715 
716 	/* only the control interface can be successfully probed */
717 	ctx->control = intf;
718 
719 	/* get some pointers */
720 	driver = driver_of(intf);
721 	buf = intf->cur_altsetting->extra;
722 	len = intf->cur_altsetting->extralen;
723 
724 	/* parse through descriptors associated with control interface */
725 	while ((len > 0) && (buf[0] > 2) && (buf[0] <= len)) {
726 
727 		if (buf[1] != USB_DT_CS_INTERFACE)
728 			goto advance;
729 
730 		switch (buf[2]) {
731 		case USB_CDC_UNION_TYPE:
732 			if (buf[0] < sizeof(*union_desc))
733 				break;
734 
735 			union_desc = (const struct usb_cdc_union_desc *)buf;
736 			/* the master must be the interface we are probing */
737 			if (intf->cur_altsetting->desc.bInterfaceNumber !=
738 			    union_desc->bMasterInterface0) {
739 				dev_dbg(&intf->dev, "bogus CDC Union\n");
740 				goto error;
741 			}
742 			ctx->data = usb_ifnum_to_if(dev->udev,
743 						    union_desc->bSlaveInterface0);
744 			break;
745 
746 		case USB_CDC_ETHERNET_TYPE:
747 			if (buf[0] < sizeof(*(ctx->ether_desc)))
748 				break;
749 
750 			ctx->ether_desc =
751 					(const struct usb_cdc_ether_desc *)buf;
752 			break;
753 
754 		case USB_CDC_NCM_TYPE:
755 			if (buf[0] < sizeof(*(ctx->func_desc)))
756 				break;
757 
758 			ctx->func_desc = (const struct usb_cdc_ncm_desc *)buf;
759 			break;
760 
761 		case USB_CDC_MBIM_TYPE:
762 			if (buf[0] < sizeof(*(ctx->mbim_desc)))
763 				break;
764 
765 			ctx->mbim_desc = (const struct usb_cdc_mbim_desc *)buf;
766 			break;
767 
768 		case USB_CDC_MBIM_EXTENDED_TYPE:
769 			if (buf[0] < sizeof(*(ctx->mbim_extended_desc)))
770 				break;
771 
772 			ctx->mbim_extended_desc =
773 				(const struct usb_cdc_mbim_extended_desc *)buf;
774 			break;
775 
776 		default:
777 			break;
778 		}
779 advance:
780 		/* advance to next descriptor */
781 		temp = buf[0];
782 		buf += temp;
783 		len -= temp;
784 	}
785 
786 	/* some buggy devices have an IAD but no CDC Union */
787 	if (!union_desc && intf->intf_assoc && intf->intf_assoc->bInterfaceCount == 2) {
788 		ctx->data = usb_ifnum_to_if(dev->udev, intf->cur_altsetting->desc.bInterfaceNumber + 1);
789 		dev_dbg(&intf->dev, "CDC Union missing - got slave from IAD\n");
790 	}
791 
792 	/* check if we got everything */
793 	if (!ctx->data) {
794 		dev_dbg(&intf->dev, "CDC Union missing and no IAD found\n");
795 		goto error;
796 	}
797 	if (cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting)) {
798 		if (!ctx->mbim_desc) {
799 			dev_dbg(&intf->dev, "MBIM functional descriptor missing\n");
800 			goto error;
801 		}
802 	} else {
803 		if (!ctx->ether_desc || !ctx->func_desc) {
804 			dev_dbg(&intf->dev, "NCM or ECM functional descriptors missing\n");
805 			goto error;
806 		}
807 	}
808 
809 	/* claim data interface, if different from control */
810 	if (ctx->data != ctx->control) {
811 		temp = usb_driver_claim_interface(driver, ctx->data, dev);
812 		if (temp) {
813 			dev_dbg(&intf->dev, "failed to claim data intf\n");
814 			goto error;
815 		}
816 	}
817 
818 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
819 
820 	/* reset data interface */
821 	temp = usb_set_interface(dev->udev, iface_no, 0);
822 	if (temp) {
823 		dev_dbg(&intf->dev, "set interface failed\n");
824 		goto error2;
825 	}
826 
827 	/* initialize basic device settings */
828 	if (cdc_ncm_init(dev))
829 		goto error2;
830 
831 	/* configure data interface */
832 	temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
833 	if (temp) {
834 		dev_dbg(&intf->dev, "set interface failed\n");
835 		goto error2;
836 	}
837 
838 	cdc_ncm_find_endpoints(dev, ctx->data);
839 	cdc_ncm_find_endpoints(dev, ctx->control);
840 	if (!dev->in || !dev->out || !dev->status) {
841 		dev_dbg(&intf->dev, "failed to collect endpoints\n");
842 		goto error2;
843 	}
844 
845 	usb_set_intfdata(ctx->data, dev);
846 	usb_set_intfdata(ctx->control, dev);
847 
848 	if (ctx->ether_desc) {
849 		temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
850 		if (temp) {
851 			dev_dbg(&intf->dev, "failed to get mac address\n");
852 			goto error2;
853 		}
854 		dev_info(&intf->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
855 	}
856 
857 	/* finish setting up the device specific data */
858 	cdc_ncm_setup(dev);
859 
860 	/* Device-specific flags */
861 	ctx->drvflags = drvflags;
862 
863 	/* Allocate the delayed NDP if needed. */
864 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
865 		ctx->delayed_ndp16 = kzalloc(ctx->max_ndp_size, GFP_KERNEL);
866 		if (!ctx->delayed_ndp16)
867 			goto error2;
868 		dev_info(&intf->dev, "NDP will be placed at end of frame for this device.");
869 	}
870 
871 	/* override ethtool_ops */
872 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
873 
874 	/* add our sysfs attrs */
875 	dev->net->sysfs_groups[0] = &cdc_ncm_sysfs_attr_group;
876 
877 	return 0;
878 
879 error2:
880 	usb_set_intfdata(ctx->control, NULL);
881 	usb_set_intfdata(ctx->data, NULL);
882 	if (ctx->data != ctx->control)
883 		usb_driver_release_interface(driver, ctx->data);
884 error:
885 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
886 	dev->data[0] = 0;
887 	dev_info(&intf->dev, "bind() failure\n");
888 	return -ENODEV;
889 }
890 EXPORT_SYMBOL_GPL(cdc_ncm_bind_common);
891 
892 void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
893 {
894 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
895 	struct usb_driver *driver = driver_of(intf);
896 
897 	if (ctx == NULL)
898 		return;		/* no setup */
899 
900 	atomic_set(&ctx->stop, 1);
901 
902 	if (hrtimer_active(&ctx->tx_timer))
903 		hrtimer_cancel(&ctx->tx_timer);
904 
905 	tasklet_kill(&ctx->bh);
906 
907 	/* handle devices with combined control and data interface */
908 	if (ctx->control == ctx->data)
909 		ctx->data = NULL;
910 
911 	/* disconnect master --> disconnect slave */
912 	if (intf == ctx->control && ctx->data) {
913 		usb_set_intfdata(ctx->data, NULL);
914 		usb_driver_release_interface(driver, ctx->data);
915 		ctx->data = NULL;
916 
917 	} else if (intf == ctx->data && ctx->control) {
918 		usb_set_intfdata(ctx->control, NULL);
919 		usb_driver_release_interface(driver, ctx->control);
920 		ctx->control = NULL;
921 	}
922 
923 	usb_set_intfdata(intf, NULL);
924 	cdc_ncm_free(ctx);
925 }
926 EXPORT_SYMBOL_GPL(cdc_ncm_unbind);
927 
928 /* Return the number of the MBIM control interface altsetting iff it
929  * is preferred and available,
930  */
931 u8 cdc_ncm_select_altsetting(struct usb_interface *intf)
932 {
933 	struct usb_host_interface *alt;
934 
935 	/* The MBIM spec defines a NCM compatible default altsetting,
936 	 * which we may have matched:
937 	 *
938 	 *  "Functions that implement both NCM 1.0 and MBIM (an
939 	 *   “NCM/MBIM function”) according to this recommendation
940 	 *   shall provide two alternate settings for the
941 	 *   Communication Interface.  Alternate setting 0, and the
942 	 *   associated class and endpoint descriptors, shall be
943 	 *   constructed according to the rules given for the
944 	 *   Communication Interface in section 5 of [USBNCM10].
945 	 *   Alternate setting 1, and the associated class and
946 	 *   endpoint descriptors, shall be constructed according to
947 	 *   the rules given in section 6 (USB Device Model) of this
948 	 *   specification."
949 	 */
950 	if (intf->num_altsetting < 2)
951 		return intf->cur_altsetting->desc.bAlternateSetting;
952 
953 	if (prefer_mbim) {
954 		alt = usb_altnum_to_altsetting(intf, CDC_NCM_COMM_ALTSETTING_MBIM);
955 		if (alt && cdc_ncm_comm_intf_is_mbim(alt))
956 			return CDC_NCM_COMM_ALTSETTING_MBIM;
957 	}
958 	return CDC_NCM_COMM_ALTSETTING_NCM;
959 }
960 EXPORT_SYMBOL_GPL(cdc_ncm_select_altsetting);
961 
962 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
963 {
964 	int ret;
965 
966 	/* MBIM backwards compatible function? */
967 	if (cdc_ncm_select_altsetting(intf) != CDC_NCM_COMM_ALTSETTING_NCM)
968 		return -ENODEV;
969 
970 	/* The NCM data altsetting is fixed, so we hard-coded it.
971 	 * Additionally, generic NCM devices are assumed to accept arbitrarily
972 	 * placed NDP.
973 	 */
974 	ret = cdc_ncm_bind_common(dev, intf, CDC_NCM_DATA_ALTSETTING_NCM, 0);
975 
976 	/*
977 	 * We should get an event when network connection is "connected" or
978 	 * "disconnected". Set network connection in "disconnected" state
979 	 * (carrier is OFF) during attach, so the IP network stack does not
980 	 * start IPv6 negotiation and more.
981 	 */
982 	usbnet_link_change(dev, 0, 0);
983 	return ret;
984 }
985 
986 static void cdc_ncm_align_tail(struct sk_buff *skb, size_t modulus, size_t remainder, size_t max)
987 {
988 	size_t align = ALIGN(skb->len, modulus) - skb->len + remainder;
989 
990 	if (skb->len + align > max)
991 		align = max - skb->len;
992 	if (align && skb_tailroom(skb) >= align)
993 		memset(skb_put(skb, align), 0, align);
994 }
995 
996 /* return a pointer to a valid struct usb_cdc_ncm_ndp16 of type sign, possibly
997  * allocating a new one within skb
998  */
999 static struct usb_cdc_ncm_ndp16 *cdc_ncm_ndp(struct cdc_ncm_ctx *ctx, struct sk_buff *skb, __le32 sign, size_t reserve)
1000 {
1001 	struct usb_cdc_ncm_ndp16 *ndp16 = NULL;
1002 	struct usb_cdc_ncm_nth16 *nth16 = (void *)skb->data;
1003 	size_t ndpoffset = le16_to_cpu(nth16->wNdpIndex);
1004 
1005 	/* If NDP should be moved to the end of the NCM package, we can't follow the
1006 	* NTH16 header as we would normally do. NDP isn't written to the SKB yet, and
1007 	* the wNdpIndex field in the header is actually not consistent with reality. It will be later.
1008 	*/
1009 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1010 		if (ctx->delayed_ndp16->dwSignature == sign)
1011 			return ctx->delayed_ndp16;
1012 
1013 	/* follow the chain of NDPs, looking for a match */
1014 	while (ndpoffset) {
1015 		ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb->data + ndpoffset);
1016 		if  (ndp16->dwSignature == sign)
1017 			return ndp16;
1018 		ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1019 	}
1020 
1021 	/* align new NDP */
1022 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1023 		cdc_ncm_align_tail(skb, ctx->tx_ndp_modulus, 0, ctx->tx_max);
1024 
1025 	/* verify that there is room for the NDP and the datagram (reserve) */
1026 	if ((ctx->tx_max - skb->len - reserve) < ctx->max_ndp_size)
1027 		return NULL;
1028 
1029 	/* link to it */
1030 	if (ndp16)
1031 		ndp16->wNextNdpIndex = cpu_to_le16(skb->len);
1032 	else
1033 		nth16->wNdpIndex = cpu_to_le16(skb->len);
1034 
1035 	/* push a new empty NDP */
1036 	if (!(ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END))
1037 		ndp16 = (struct usb_cdc_ncm_ndp16 *)memset(skb_put(skb, ctx->max_ndp_size), 0, ctx->max_ndp_size);
1038 	else
1039 		ndp16 = ctx->delayed_ndp16;
1040 
1041 	ndp16->dwSignature = sign;
1042 	ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) + sizeof(struct usb_cdc_ncm_dpe16));
1043 	return ndp16;
1044 }
1045 
1046 struct sk_buff *
1047 cdc_ncm_fill_tx_frame(struct usbnet *dev, struct sk_buff *skb, __le32 sign)
1048 {
1049 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1050 	struct usb_cdc_ncm_nth16 *nth16;
1051 	struct usb_cdc_ncm_ndp16 *ndp16;
1052 	struct sk_buff *skb_out;
1053 	u16 n = 0, index, ndplen;
1054 	u8 ready2send = 0;
1055 	u32 delayed_ndp_size;
1056 
1057 	/* When our NDP gets written in cdc_ncm_ndp(), then skb_out->len gets updated
1058 	 * accordingly. Otherwise, we should check here.
1059 	 */
1060 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END)
1061 		delayed_ndp_size = ctx->max_ndp_size;
1062 	else
1063 		delayed_ndp_size = 0;
1064 
1065 	/* if there is a remaining skb, it gets priority */
1066 	if (skb != NULL) {
1067 		swap(skb, ctx->tx_rem_skb);
1068 		swap(sign, ctx->tx_rem_sign);
1069 	} else {
1070 		ready2send = 1;
1071 	}
1072 
1073 	/* check if we are resuming an OUT skb */
1074 	skb_out = ctx->tx_curr_skb;
1075 
1076 	/* allocate a new OUT skb */
1077 	if (!skb_out) {
1078 		skb_out = alloc_skb(ctx->tx_max, GFP_ATOMIC);
1079 		if (skb_out == NULL) {
1080 			if (skb != NULL) {
1081 				dev_kfree_skb_any(skb);
1082 				dev->net->stats.tx_dropped++;
1083 			}
1084 			goto exit_no_skb;
1085 		}
1086 		/* fill out the initial 16-bit NTB header */
1087 		nth16 = (struct usb_cdc_ncm_nth16 *)memset(skb_put(skb_out, sizeof(struct usb_cdc_ncm_nth16)), 0, sizeof(struct usb_cdc_ncm_nth16));
1088 		nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
1089 		nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16));
1090 		nth16->wSequence = cpu_to_le16(ctx->tx_seq++);
1091 
1092 		/* count total number of frames in this NTB */
1093 		ctx->tx_curr_frame_num = 0;
1094 
1095 		/* recent payload counter for this skb_out */
1096 		ctx->tx_curr_frame_payload = 0;
1097 	}
1098 
1099 	for (n = ctx->tx_curr_frame_num; n < ctx->tx_max_datagrams; n++) {
1100 		/* send any remaining skb first */
1101 		if (skb == NULL) {
1102 			skb = ctx->tx_rem_skb;
1103 			sign = ctx->tx_rem_sign;
1104 			ctx->tx_rem_skb = NULL;
1105 
1106 			/* check for end of skb */
1107 			if (skb == NULL)
1108 				break;
1109 		}
1110 
1111 		/* get the appropriate NDP for this skb */
1112 		ndp16 = cdc_ncm_ndp(ctx, skb_out, sign, skb->len + ctx->tx_modulus + ctx->tx_remainder);
1113 
1114 		/* align beginning of next frame */
1115 		cdc_ncm_align_tail(skb_out,  ctx->tx_modulus, ctx->tx_remainder, ctx->tx_max);
1116 
1117 		/* check if we had enough room left for both NDP and frame */
1118 		if (!ndp16 || skb_out->len + skb->len + delayed_ndp_size > ctx->tx_max) {
1119 			if (n == 0) {
1120 				/* won't fit, MTU problem? */
1121 				dev_kfree_skb_any(skb);
1122 				skb = NULL;
1123 				dev->net->stats.tx_dropped++;
1124 			} else {
1125 				/* no room for skb - store for later */
1126 				if (ctx->tx_rem_skb != NULL) {
1127 					dev_kfree_skb_any(ctx->tx_rem_skb);
1128 					dev->net->stats.tx_dropped++;
1129 				}
1130 				ctx->tx_rem_skb = skb;
1131 				ctx->tx_rem_sign = sign;
1132 				skb = NULL;
1133 				ready2send = 1;
1134 				ctx->tx_reason_ntb_full++;	/* count reason for transmitting */
1135 			}
1136 			break;
1137 		}
1138 
1139 		/* calculate frame number withing this NDP */
1140 		ndplen = le16_to_cpu(ndp16->wLength);
1141 		index = (ndplen - sizeof(struct usb_cdc_ncm_ndp16)) / sizeof(struct usb_cdc_ncm_dpe16) - 1;
1142 
1143 		/* OK, add this skb */
1144 		ndp16->dpe16[index].wDatagramLength = cpu_to_le16(skb->len);
1145 		ndp16->dpe16[index].wDatagramIndex = cpu_to_le16(skb_out->len);
1146 		ndp16->wLength = cpu_to_le16(ndplen + sizeof(struct usb_cdc_ncm_dpe16));
1147 		memcpy(skb_put(skb_out, skb->len), skb->data, skb->len);
1148 		ctx->tx_curr_frame_payload += skb->len;	/* count real tx payload data */
1149 		dev_kfree_skb_any(skb);
1150 		skb = NULL;
1151 
1152 		/* send now if this NDP is full */
1153 		if (index >= CDC_NCM_DPT_DATAGRAMS_MAX) {
1154 			ready2send = 1;
1155 			ctx->tx_reason_ndp_full++;	/* count reason for transmitting */
1156 			break;
1157 		}
1158 	}
1159 
1160 	/* free up any dangling skb */
1161 	if (skb != NULL) {
1162 		dev_kfree_skb_any(skb);
1163 		skb = NULL;
1164 		dev->net->stats.tx_dropped++;
1165 	}
1166 
1167 	ctx->tx_curr_frame_num = n;
1168 
1169 	if (n == 0) {
1170 		/* wait for more frames */
1171 		/* push variables */
1172 		ctx->tx_curr_skb = skb_out;
1173 		goto exit_no_skb;
1174 
1175 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0) && (ctx->timer_interval > 0)) {
1176 		/* wait for more frames */
1177 		/* push variables */
1178 		ctx->tx_curr_skb = skb_out;
1179 		/* set the pending count */
1180 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
1181 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
1182 		goto exit_no_skb;
1183 
1184 	} else {
1185 		if (n == ctx->tx_max_datagrams)
1186 			ctx->tx_reason_max_datagram++;	/* count reason for transmitting */
1187 		/* frame goes out */
1188 		/* variables will be reset at next call */
1189 	}
1190 
1191 	/* If requested, put NDP at end of frame. */
1192 	if (ctx->drvflags & CDC_NCM_FLAG_NDP_TO_END) {
1193 		nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1194 		cdc_ncm_align_tail(skb_out, ctx->tx_ndp_modulus, 0, ctx->tx_max);
1195 		nth16->wNdpIndex = cpu_to_le16(skb_out->len);
1196 		memcpy(skb_put(skb_out, ctx->max_ndp_size), ctx->delayed_ndp16, ctx->max_ndp_size);
1197 
1198 		/* Zero out delayed NDP - signature checking will naturally fail. */
1199 		ndp16 = memset(ctx->delayed_ndp16, 0, ctx->max_ndp_size);
1200 	}
1201 
1202 	/* If collected data size is less or equal ctx->min_tx_pkt
1203 	 * bytes, we send buffers as it is. If we get more data, it
1204 	 * would be more efficient for USB HS mobile device with DMA
1205 	 * engine to receive a full size NTB, than canceling DMA
1206 	 * transfer and receiving a short packet.
1207 	 *
1208 	 * This optimization support is pointless if we end up sending
1209 	 * a ZLP after full sized NTBs.
1210 	 */
1211 	if (!(dev->driver_info->flags & FLAG_SEND_ZLP) &&
1212 	    skb_out->len > ctx->min_tx_pkt)
1213 		memset(skb_put(skb_out, ctx->tx_max - skb_out->len), 0,
1214 		       ctx->tx_max - skb_out->len);
1215 	else if (skb_out->len < ctx->tx_max && (skb_out->len % dev->maxpacket) == 0)
1216 		*skb_put(skb_out, 1) = 0;	/* force short packet */
1217 
1218 	/* set final frame length */
1219 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_out->data;
1220 	nth16->wBlockLength = cpu_to_le16(skb_out->len);
1221 
1222 	/* return skb */
1223 	ctx->tx_curr_skb = NULL;
1224 
1225 	/* keep private stats: framing overhead and number of NTBs */
1226 	ctx->tx_overhead += skb_out->len - ctx->tx_curr_frame_payload;
1227 	ctx->tx_ntbs++;
1228 
1229 	/* usbnet will count all the framing overhead by default.
1230 	 * Adjust the stats so that the tx_bytes counter show real
1231 	 * payload data instead.
1232 	 */
1233 	usbnet_set_skb_tx_stats(skb_out, n,
1234 				(long)ctx->tx_curr_frame_payload - skb_out->len);
1235 
1236 	return skb_out;
1237 
1238 exit_no_skb:
1239 	/* Start timer, if there is a remaining non-empty skb */
1240 	if (ctx->tx_curr_skb != NULL && n > 0)
1241 		cdc_ncm_tx_timeout_start(ctx);
1242 	return NULL;
1243 }
1244 EXPORT_SYMBOL_GPL(cdc_ncm_fill_tx_frame);
1245 
1246 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
1247 {
1248 	/* start timer, if not already started */
1249 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
1250 		hrtimer_start(&ctx->tx_timer,
1251 				ktime_set(0, ctx->timer_interval),
1252 				HRTIMER_MODE_REL);
1253 }
1254 
1255 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
1256 {
1257 	struct cdc_ncm_ctx *ctx =
1258 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
1259 
1260 	if (!atomic_read(&ctx->stop))
1261 		tasklet_schedule(&ctx->bh);
1262 	return HRTIMER_NORESTART;
1263 }
1264 
1265 static void cdc_ncm_txpath_bh(unsigned long param)
1266 {
1267 	struct usbnet *dev = (struct usbnet *)param;
1268 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1269 
1270 	spin_lock_bh(&ctx->mtx);
1271 	if (ctx->tx_timer_pending != 0) {
1272 		ctx->tx_timer_pending--;
1273 		cdc_ncm_tx_timeout_start(ctx);
1274 		spin_unlock_bh(&ctx->mtx);
1275 	} else if (dev->net != NULL) {
1276 		ctx->tx_reason_timeout++;	/* count reason for transmitting */
1277 		spin_unlock_bh(&ctx->mtx);
1278 		netif_tx_lock_bh(dev->net);
1279 		usbnet_start_xmit(NULL, dev->net);
1280 		netif_tx_unlock_bh(dev->net);
1281 	} else {
1282 		spin_unlock_bh(&ctx->mtx);
1283 	}
1284 }
1285 
1286 struct sk_buff *
1287 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
1288 {
1289 	struct sk_buff *skb_out;
1290 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1291 
1292 	/*
1293 	 * The Ethernet API we are using does not support transmitting
1294 	 * multiple Ethernet frames in a single call. This driver will
1295 	 * accumulate multiple Ethernet frames and send out a larger
1296 	 * USB frame when the USB buffer is full or when a single jiffies
1297 	 * timeout happens.
1298 	 */
1299 	if (ctx == NULL)
1300 		goto error;
1301 
1302 	spin_lock_bh(&ctx->mtx);
1303 	skb_out = cdc_ncm_fill_tx_frame(dev, skb, cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN));
1304 	spin_unlock_bh(&ctx->mtx);
1305 	return skb_out;
1306 
1307 error:
1308 	if (skb != NULL)
1309 		dev_kfree_skb_any(skb);
1310 
1311 	return NULL;
1312 }
1313 EXPORT_SYMBOL_GPL(cdc_ncm_tx_fixup);
1314 
1315 /* verify NTB header and return offset of first NDP, or negative error */
1316 int cdc_ncm_rx_verify_nth16(struct cdc_ncm_ctx *ctx, struct sk_buff *skb_in)
1317 {
1318 	struct usbnet *dev = netdev_priv(skb_in->dev);
1319 	struct usb_cdc_ncm_nth16 *nth16;
1320 	int len;
1321 	int ret = -EINVAL;
1322 
1323 	if (ctx == NULL)
1324 		goto error;
1325 
1326 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
1327 					sizeof(struct usb_cdc_ncm_ndp16))) {
1328 		netif_dbg(dev, rx_err, dev->net, "frame too short\n");
1329 		goto error;
1330 	}
1331 
1332 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
1333 
1334 	if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) {
1335 		netif_dbg(dev, rx_err, dev->net,
1336 			  "invalid NTH16 signature <%#010x>\n",
1337 			  le32_to_cpu(nth16->dwSignature));
1338 		goto error;
1339 	}
1340 
1341 	len = le16_to_cpu(nth16->wBlockLength);
1342 	if (len > ctx->rx_max) {
1343 		netif_dbg(dev, rx_err, dev->net,
1344 			  "unsupported NTB block length %u/%u\n", len,
1345 			  ctx->rx_max);
1346 		goto error;
1347 	}
1348 
1349 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
1350 	    (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
1351 	    !((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
1352 		netif_dbg(dev, rx_err, dev->net,
1353 			  "sequence number glitch prev=%d curr=%d\n",
1354 			  ctx->rx_seq, le16_to_cpu(nth16->wSequence));
1355 	}
1356 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
1357 
1358 	ret = le16_to_cpu(nth16->wNdpIndex);
1359 error:
1360 	return ret;
1361 }
1362 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_nth16);
1363 
1364 /* verify NDP header and return number of datagrams, or negative error */
1365 int cdc_ncm_rx_verify_ndp16(struct sk_buff *skb_in, int ndpoffset)
1366 {
1367 	struct usbnet *dev = netdev_priv(skb_in->dev);
1368 	struct usb_cdc_ncm_ndp16 *ndp16;
1369 	int ret = -EINVAL;
1370 
1371 	if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
1372 		netif_dbg(dev, rx_err, dev->net, "invalid NDP offset  <%u>\n",
1373 			  ndpoffset);
1374 		goto error;
1375 	}
1376 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1377 
1378 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1379 		netif_dbg(dev, rx_err, dev->net, "invalid DPT16 length <%u>\n",
1380 			  le16_to_cpu(ndp16->wLength));
1381 		goto error;
1382 	}
1383 
1384 	ret = ((le16_to_cpu(ndp16->wLength) -
1385 					sizeof(struct usb_cdc_ncm_ndp16)) /
1386 					sizeof(struct usb_cdc_ncm_dpe16));
1387 	ret--; /* we process NDP entries except for the last one */
1388 
1389 	if ((sizeof(struct usb_cdc_ncm_ndp16) +
1390 	     ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) {
1391 		netif_dbg(dev, rx_err, dev->net, "Invalid nframes = %d\n", ret);
1392 		ret = -EINVAL;
1393 	}
1394 
1395 error:
1396 	return ret;
1397 }
1398 EXPORT_SYMBOL_GPL(cdc_ncm_rx_verify_ndp16);
1399 
1400 int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
1401 {
1402 	struct sk_buff *skb;
1403 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
1404 	int len;
1405 	int nframes;
1406 	int x;
1407 	int offset;
1408 	struct usb_cdc_ncm_ndp16 *ndp16;
1409 	struct usb_cdc_ncm_dpe16 *dpe16;
1410 	int ndpoffset;
1411 	int loopcount = 50; /* arbitrary max preventing infinite loop */
1412 	u32 payload = 0;
1413 
1414 	ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
1415 	if (ndpoffset < 0)
1416 		goto error;
1417 
1418 next_ndp:
1419 	nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
1420 	if (nframes < 0)
1421 		goto error;
1422 
1423 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
1424 
1425 	if (ndp16->dwSignature != cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN)) {
1426 		netif_dbg(dev, rx_err, dev->net,
1427 			  "invalid DPT16 signature <%#010x>\n",
1428 			  le32_to_cpu(ndp16->dwSignature));
1429 		goto err_ndp;
1430 	}
1431 	dpe16 = ndp16->dpe16;
1432 
1433 	for (x = 0; x < nframes; x++, dpe16++) {
1434 		offset = le16_to_cpu(dpe16->wDatagramIndex);
1435 		len = le16_to_cpu(dpe16->wDatagramLength);
1436 
1437 		/*
1438 		 * CDC NCM ch. 3.7
1439 		 * All entries after first NULL entry are to be ignored
1440 		 */
1441 		if ((offset == 0) || (len == 0)) {
1442 			if (!x)
1443 				goto err_ndp; /* empty NTB */
1444 			break;
1445 		}
1446 
1447 		/* sanity checking */
1448 		if (((offset + len) > skb_in->len) ||
1449 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1450 			netif_dbg(dev, rx_err, dev->net,
1451 				  "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
1452 				  x, offset, len, skb_in);
1453 			if (!x)
1454 				goto err_ndp;
1455 			break;
1456 
1457 		} else {
1458 			/* create a fresh copy to reduce truesize */
1459 			skb = netdev_alloc_skb_ip_align(dev->net,  len);
1460 			if (!skb)
1461 				goto error;
1462 			memcpy(skb_put(skb, len), skb_in->data + offset, len);
1463 			usbnet_skb_return(dev, skb);
1464 			payload += len;	/* count payload bytes in this NTB */
1465 		}
1466 	}
1467 err_ndp:
1468 	/* are there more NDPs to process? */
1469 	ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
1470 	if (ndpoffset && loopcount--)
1471 		goto next_ndp;
1472 
1473 	/* update stats */
1474 	ctx->rx_overhead += skb_in->len - payload;
1475 	ctx->rx_ntbs++;
1476 
1477 	return 1;
1478 error:
1479 	return 0;
1480 }
1481 EXPORT_SYMBOL_GPL(cdc_ncm_rx_fixup);
1482 
1483 static void
1484 cdc_ncm_speed_change(struct usbnet *dev,
1485 		     struct usb_cdc_speed_change *data)
1486 {
1487 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1488 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1489 
1490 	/*
1491 	 * Currently the USB-NET API does not support reporting the actual
1492 	 * device speed. Do print it instead.
1493 	 */
1494 	if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1495 		netif_info(dev, link, dev->net,
1496 			   "%u mbit/s downlink %u mbit/s uplink\n",
1497 			   (unsigned int)(rx_speed / 1000000U),
1498 			   (unsigned int)(tx_speed / 1000000U));
1499 	} else {
1500 		netif_info(dev, link, dev->net,
1501 			   "%u kbit/s downlink %u kbit/s uplink\n",
1502 			   (unsigned int)(rx_speed / 1000U),
1503 			   (unsigned int)(tx_speed / 1000U));
1504 	}
1505 }
1506 
1507 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1508 {
1509 	struct cdc_ncm_ctx *ctx;
1510 	struct usb_cdc_notification *event;
1511 
1512 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1513 
1514 	if (urb->actual_length < sizeof(*event))
1515 		return;
1516 
1517 	/* test for split data in 8-byte chunks */
1518 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1519 		cdc_ncm_speed_change(dev,
1520 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1521 		return;
1522 	}
1523 
1524 	event = urb->transfer_buffer;
1525 
1526 	switch (event->bNotificationType) {
1527 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1528 		/*
1529 		 * According to the CDC NCM specification ch.7.1
1530 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1531 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1532 		 */
1533 		netif_info(dev, link, dev->net,
1534 			   "network connection: %sconnected\n",
1535 			   !!event->wValue ? "" : "dis");
1536 		usbnet_link_change(dev, !!event->wValue, 0);
1537 		break;
1538 
1539 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1540 		if (urb->actual_length < (sizeof(*event) +
1541 					sizeof(struct usb_cdc_speed_change)))
1542 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1543 		else
1544 			cdc_ncm_speed_change(dev,
1545 					     (struct usb_cdc_speed_change *)&event[1]);
1546 		break;
1547 
1548 	default:
1549 		dev_dbg(&dev->udev->dev,
1550 			"NCM: unexpected notification 0x%02x!\n",
1551 			event->bNotificationType);
1552 		break;
1553 	}
1554 }
1555 
1556 static const struct driver_info cdc_ncm_info = {
1557 	.description = "CDC NCM",
1558 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET,
1559 	.bind = cdc_ncm_bind,
1560 	.unbind = cdc_ncm_unbind,
1561 	.manage_power = usbnet_manage_power,
1562 	.status = cdc_ncm_status,
1563 	.rx_fixup = cdc_ncm_rx_fixup,
1564 	.tx_fixup = cdc_ncm_tx_fixup,
1565 };
1566 
1567 /* Same as cdc_ncm_info, but with FLAG_WWAN */
1568 static const struct driver_info wwan_info = {
1569 	.description = "Mobile Broadband Network Device",
1570 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1571 			| FLAG_WWAN,
1572 	.bind = cdc_ncm_bind,
1573 	.unbind = cdc_ncm_unbind,
1574 	.manage_power = usbnet_manage_power,
1575 	.status = cdc_ncm_status,
1576 	.rx_fixup = cdc_ncm_rx_fixup,
1577 	.tx_fixup = cdc_ncm_tx_fixup,
1578 };
1579 
1580 /* Same as wwan_info, but with FLAG_NOARP  */
1581 static const struct driver_info wwan_noarp_info = {
1582 	.description = "Mobile Broadband Network Device (NO ARP)",
1583 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1584 			| FLAG_WWAN | FLAG_NOARP,
1585 	.bind = cdc_ncm_bind,
1586 	.unbind = cdc_ncm_unbind,
1587 	.manage_power = usbnet_manage_power,
1588 	.status = cdc_ncm_status,
1589 	.rx_fixup = cdc_ncm_rx_fixup,
1590 	.tx_fixup = cdc_ncm_tx_fixup,
1591 };
1592 
1593 static const struct usb_device_id cdc_devs[] = {
1594 	/* Ericsson MBM devices like F5521gw */
1595 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1596 		| USB_DEVICE_ID_MATCH_VENDOR,
1597 	  .idVendor = 0x0bdb,
1598 	  .bInterfaceClass = USB_CLASS_COMM,
1599 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1600 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1601 	  .driver_info = (unsigned long) &wwan_info,
1602 	},
1603 
1604 	/* Dell branded MBM devices like DW5550 */
1605 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1606 		| USB_DEVICE_ID_MATCH_VENDOR,
1607 	  .idVendor = 0x413c,
1608 	  .bInterfaceClass = USB_CLASS_COMM,
1609 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1610 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1611 	  .driver_info = (unsigned long) &wwan_info,
1612 	},
1613 
1614 	/* Toshiba branded MBM devices */
1615 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1616 		| USB_DEVICE_ID_MATCH_VENDOR,
1617 	  .idVendor = 0x0930,
1618 	  .bInterfaceClass = USB_CLASS_COMM,
1619 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1620 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1621 	  .driver_info = (unsigned long) &wwan_info,
1622 	},
1623 
1624 	/* tag Huawei devices as wwan */
1625 	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1,
1626 					USB_CLASS_COMM,
1627 					USB_CDC_SUBCLASS_NCM,
1628 					USB_CDC_PROTO_NONE),
1629 	  .driver_info = (unsigned long)&wwan_info,
1630 	},
1631 
1632 	/* Infineon(now Intel) HSPA Modem platform */
1633 	{ USB_DEVICE_AND_INTERFACE_INFO(0x1519, 0x0443,
1634 		USB_CLASS_COMM,
1635 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1636 	  .driver_info = (unsigned long)&wwan_noarp_info,
1637 	},
1638 
1639 	/* Generic CDC-NCM devices */
1640 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
1641 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1642 		.driver_info = (unsigned long)&cdc_ncm_info,
1643 	},
1644 	{
1645 	},
1646 };
1647 MODULE_DEVICE_TABLE(usb, cdc_devs);
1648 
1649 static struct usb_driver cdc_ncm_driver = {
1650 	.name = "cdc_ncm",
1651 	.id_table = cdc_devs,
1652 	.probe = usbnet_probe,
1653 	.disconnect = usbnet_disconnect,
1654 	.suspend = usbnet_suspend,
1655 	.resume = usbnet_resume,
1656 	.reset_resume =	usbnet_resume,
1657 	.supports_autosuspend = 1,
1658 	.disable_hub_initiated_lpm = 1,
1659 };
1660 
1661 module_usb_driver(cdc_ncm_driver);
1662 
1663 MODULE_AUTHOR("Hans Petter Selasky");
1664 MODULE_DESCRIPTION("USB CDC NCM host driver");
1665 MODULE_LICENSE("Dual BSD/GPL");
1666