xref: /linux/drivers/net/usb/cdc_ncm.c (revision 7c43185138cf523b0810ffd2c9e18e2ecb356730)
1 /*
2  * cdc_ncm.c
3  *
4  * Copyright (C) ST-Ericsson 2010-2011
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/devclass_docs/NCM10.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/init.h>
43 #include <linux/netdevice.h>
44 #include <linux/ctype.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/timer.h>
51 #include <linux/spinlock.h>
52 #include <linux/atomic.h>
53 #include <linux/usb/usbnet.h>
54 #include <linux/usb/cdc.h>
55 
56 #define	DRIVER_VERSION				"04-Aug-2011"
57 
58 /* CDC NCM subclass 3.2.1 */
59 #define USB_CDC_NCM_NDP16_LENGTH_MIN		0x10
60 
61 /* Maximum NTB length */
62 #define	CDC_NCM_NTB_MAX_SIZE_TX			16384	/* bytes */
63 #define	CDC_NCM_NTB_MAX_SIZE_RX			16384	/* bytes */
64 
65 /* Minimum value for MaxDatagramSize, ch. 6.2.9 */
66 #define	CDC_NCM_MIN_DATAGRAM_SIZE		1514	/* bytes */
67 
68 #define	CDC_NCM_MIN_TX_PKT			512	/* bytes */
69 
70 /* Default value for MaxDatagramSize */
71 #define	CDC_NCM_MAX_DATAGRAM_SIZE		2048	/* bytes */
72 
73 /*
74  * Maximum amount of datagrams in NCM Datagram Pointer Table, not counting
75  * the last NULL entry. Any additional datagrams in NTB would be discarded.
76  */
77 #define	CDC_NCM_DPT_DATAGRAMS_MAX		32
78 
79 /* Maximum amount of IN datagrams in NTB */
80 #define	CDC_NCM_DPT_DATAGRAMS_IN_MAX		0 /* unlimited */
81 
82 /* Restart the timer, if amount of datagrams is less than given value */
83 #define	CDC_NCM_RESTART_TIMER_DATAGRAM_CNT	3
84 
85 /* The following macro defines the minimum header space */
86 #define	CDC_NCM_MIN_HDR_SIZE \
87 	(sizeof(struct usb_cdc_ncm_nth16) + sizeof(struct usb_cdc_ncm_ndp16) + \
88 	(CDC_NCM_DPT_DATAGRAMS_MAX + 1) * sizeof(struct usb_cdc_ncm_dpe16))
89 
90 struct cdc_ncm_data {
91 	struct usb_cdc_ncm_nth16 nth16;
92 	struct usb_cdc_ncm_ndp16 ndp16;
93 	struct usb_cdc_ncm_dpe16 dpe16[CDC_NCM_DPT_DATAGRAMS_MAX + 1];
94 };
95 
96 struct cdc_ncm_ctx {
97 	struct cdc_ncm_data rx_ncm;
98 	struct cdc_ncm_data tx_ncm;
99 	struct usb_cdc_ncm_ntb_parameters ncm_parm;
100 	struct timer_list tx_timer;
101 
102 	const struct usb_cdc_ncm_desc *func_desc;
103 	const struct usb_cdc_header_desc *header_desc;
104 	const struct usb_cdc_union_desc *union_desc;
105 	const struct usb_cdc_ether_desc *ether_desc;
106 
107 	struct net_device *netdev;
108 	struct usb_device *udev;
109 	struct usb_host_endpoint *in_ep;
110 	struct usb_host_endpoint *out_ep;
111 	struct usb_host_endpoint *status_ep;
112 	struct usb_interface *intf;
113 	struct usb_interface *control;
114 	struct usb_interface *data;
115 
116 	struct sk_buff *tx_curr_skb;
117 	struct sk_buff *tx_rem_skb;
118 
119 	spinlock_t mtx;
120 
121 	u32 tx_timer_pending;
122 	u32 tx_curr_offset;
123 	u32 tx_curr_last_offset;
124 	u32 tx_curr_frame_num;
125 	u32 rx_speed;
126 	u32 tx_speed;
127 	u32 rx_max;
128 	u32 tx_max;
129 	u32 max_datagram_size;
130 	u16 tx_max_datagrams;
131 	u16 tx_remainder;
132 	u16 tx_modulus;
133 	u16 tx_ndp_modulus;
134 	u16 tx_seq;
135 	u16 connected;
136 };
137 
138 static void cdc_ncm_tx_timeout(unsigned long arg);
139 static const struct driver_info cdc_ncm_info;
140 static struct usb_driver cdc_ncm_driver;
141 static struct ethtool_ops cdc_ncm_ethtool_ops;
142 
143 static const struct usb_device_id cdc_devs[] = {
144 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
145 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
146 		.driver_info = (unsigned long)&cdc_ncm_info,
147 	},
148 	{
149 	},
150 };
151 
152 MODULE_DEVICE_TABLE(usb, cdc_devs);
153 
154 static void
155 cdc_ncm_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
156 {
157 	struct usbnet *dev = netdev_priv(net);
158 
159 	strncpy(info->driver, dev->driver_name, sizeof(info->driver));
160 	strncpy(info->version, DRIVER_VERSION, sizeof(info->version));
161 	strncpy(info->fw_version, dev->driver_info->description,
162 		sizeof(info->fw_version));
163 	usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
164 }
165 
166 static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
167 {
168 	u32 val;
169 	u8 flags;
170 	u8 iface_no;
171 	int err;
172 	u16 ntb_fmt_supported;
173 
174 	iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
175 
176 	err = usb_control_msg(ctx->udev,
177 				usb_rcvctrlpipe(ctx->udev, 0),
178 				USB_CDC_GET_NTB_PARAMETERS,
179 				USB_TYPE_CLASS | USB_DIR_IN
180 				 | USB_RECIP_INTERFACE,
181 				0, iface_no, &ctx->ncm_parm,
182 				sizeof(ctx->ncm_parm), 10000);
183 	if (err < 0) {
184 		pr_debug("failed GET_NTB_PARAMETERS\n");
185 		return 1;
186 	}
187 
188 	/* read correct set of parameters according to device mode */
189 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
190 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
191 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
192 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
193 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
194 	/* devices prior to NCM Errata shall set this field to zero */
195 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
196 	ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
197 
198 	if (ctx->func_desc != NULL)
199 		flags = ctx->func_desc->bmNetworkCapabilities;
200 	else
201 		flags = 0;
202 
203 	pr_debug("dwNtbInMaxSize=%u dwNtbOutMaxSize=%u "
204 		 "wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u "
205 		 "wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
206 		 ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
207 		 ctx->tx_ndp_modulus, ctx->tx_max_datagrams, flags);
208 
209 	/* max count of tx datagrams */
210 	if ((ctx->tx_max_datagrams == 0) ||
211 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
212 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
213 
214 	/* verify maximum size of received NTB in bytes */
215 	if (ctx->rx_max < USB_CDC_NCM_NTB_MIN_IN_SIZE) {
216 		pr_debug("Using min receive length=%d\n",
217 						USB_CDC_NCM_NTB_MIN_IN_SIZE);
218 		ctx->rx_max = USB_CDC_NCM_NTB_MIN_IN_SIZE;
219 	}
220 
221 	if (ctx->rx_max > CDC_NCM_NTB_MAX_SIZE_RX) {
222 		pr_debug("Using default maximum receive length=%d\n",
223 						CDC_NCM_NTB_MAX_SIZE_RX);
224 		ctx->rx_max = CDC_NCM_NTB_MAX_SIZE_RX;
225 	}
226 
227 	/* inform device about NTB input size changes */
228 	if (ctx->rx_max != le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize)) {
229 
230 		if (flags & USB_CDC_NCM_NCAP_NTB_INPUT_SIZE) {
231 			struct usb_cdc_ncm_ndp_input_size ndp_in_sz;
232 			err = usb_control_msg(ctx->udev,
233 					usb_sndctrlpipe(ctx->udev, 0),
234 					USB_CDC_SET_NTB_INPUT_SIZE,
235 					USB_TYPE_CLASS | USB_DIR_OUT
236 					 | USB_RECIP_INTERFACE,
237 					0, iface_no, &ndp_in_sz, 8, 1000);
238 		} else {
239 			__le32 dwNtbInMaxSize = cpu_to_le32(ctx->rx_max);
240 			err = usb_control_msg(ctx->udev,
241 					usb_sndctrlpipe(ctx->udev, 0),
242 					USB_CDC_SET_NTB_INPUT_SIZE,
243 					USB_TYPE_CLASS | USB_DIR_OUT
244 					 | USB_RECIP_INTERFACE,
245 					0, iface_no, &dwNtbInMaxSize, 4, 1000);
246 		}
247 
248 		if (err < 0)
249 			pr_debug("Setting NTB Input Size failed\n");
250 	}
251 
252 	/* verify maximum size of transmitted NTB in bytes */
253 	if ((ctx->tx_max <
254 	    (CDC_NCM_MIN_HDR_SIZE + CDC_NCM_MIN_DATAGRAM_SIZE)) ||
255 	    (ctx->tx_max > CDC_NCM_NTB_MAX_SIZE_TX)) {
256 		pr_debug("Using default maximum transmit length=%d\n",
257 						CDC_NCM_NTB_MAX_SIZE_TX);
258 		ctx->tx_max = CDC_NCM_NTB_MAX_SIZE_TX;
259 	}
260 
261 	/*
262 	 * verify that the structure alignment is:
263 	 * - power of two
264 	 * - not greater than the maximum transmit length
265 	 * - not less than four bytes
266 	 */
267 	val = ctx->tx_ndp_modulus;
268 
269 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
270 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
271 		pr_debug("Using default alignment: 4 bytes\n");
272 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
273 	}
274 
275 	/*
276 	 * verify that the payload alignment is:
277 	 * - power of two
278 	 * - not greater than the maximum transmit length
279 	 * - not less than four bytes
280 	 */
281 	val = ctx->tx_modulus;
282 
283 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
284 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
285 		pr_debug("Using default transmit modulus: 4 bytes\n");
286 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
287 	}
288 
289 	/* verify the payload remainder */
290 	if (ctx->tx_remainder >= ctx->tx_modulus) {
291 		pr_debug("Using default transmit remainder: 0 bytes\n");
292 		ctx->tx_remainder = 0;
293 	}
294 
295 	/* adjust TX-remainder according to NCM specification. */
296 	ctx->tx_remainder = ((ctx->tx_remainder - ETH_HLEN) &
297 						(ctx->tx_modulus - 1));
298 
299 	/* additional configuration */
300 
301 	/* set CRC Mode */
302 	if (flags & USB_CDC_NCM_NCAP_CRC_MODE) {
303 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
304 				USB_CDC_SET_CRC_MODE,
305 				USB_TYPE_CLASS | USB_DIR_OUT
306 				 | USB_RECIP_INTERFACE,
307 				USB_CDC_NCM_CRC_NOT_APPENDED,
308 				iface_no, NULL, 0, 1000);
309 		if (err < 0)
310 			pr_debug("Setting CRC mode off failed\n");
311 	}
312 
313 	/* set NTB format, if both formats are supported */
314 	if (ntb_fmt_supported & USB_CDC_NCM_NTH32_SIGN) {
315 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
316 				USB_CDC_SET_NTB_FORMAT, USB_TYPE_CLASS
317 				 | USB_DIR_OUT | USB_RECIP_INTERFACE,
318 				USB_CDC_NCM_NTB16_FORMAT,
319 				iface_no, NULL, 0, 1000);
320 		if (err < 0)
321 			pr_debug("Setting NTB format to 16-bit failed\n");
322 	}
323 
324 	ctx->max_datagram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
325 
326 	/* set Max Datagram Size (MTU) */
327 	if (flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE) {
328 		__le16 max_datagram_size;
329 		u16 eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
330 		err = usb_control_msg(ctx->udev, usb_rcvctrlpipe(ctx->udev, 0),
331 				USB_CDC_GET_MAX_DATAGRAM_SIZE,
332 				USB_TYPE_CLASS | USB_DIR_IN
333 				 | USB_RECIP_INTERFACE,
334 				0, iface_no, &max_datagram_size,
335 				2, 1000);
336 		if (err < 0) {
337 			pr_debug("GET_MAX_DATAGRAM_SIZE failed, use size=%u\n",
338 						CDC_NCM_MIN_DATAGRAM_SIZE);
339 		} else {
340 			ctx->max_datagram_size = le16_to_cpu(max_datagram_size);
341 			/* Check Eth descriptor value */
342 			if (eth_max_sz < CDC_NCM_MAX_DATAGRAM_SIZE) {
343 				if (ctx->max_datagram_size > eth_max_sz)
344 					ctx->max_datagram_size = eth_max_sz;
345 			} else {
346 				if (ctx->max_datagram_size >
347 						CDC_NCM_MAX_DATAGRAM_SIZE)
348 					ctx->max_datagram_size =
349 						CDC_NCM_MAX_DATAGRAM_SIZE;
350 			}
351 
352 			if (ctx->max_datagram_size < CDC_NCM_MIN_DATAGRAM_SIZE)
353 				ctx->max_datagram_size =
354 					CDC_NCM_MIN_DATAGRAM_SIZE;
355 
356 			/* if value changed, update device */
357 			err = usb_control_msg(ctx->udev,
358 						usb_sndctrlpipe(ctx->udev, 0),
359 						USB_CDC_SET_MAX_DATAGRAM_SIZE,
360 						USB_TYPE_CLASS | USB_DIR_OUT
361 						 | USB_RECIP_INTERFACE,
362 						0,
363 						iface_no, &max_datagram_size,
364 						2, 1000);
365 			if (err < 0)
366 				pr_debug("SET_MAX_DATAGRAM_SIZE failed\n");
367 		}
368 
369 	}
370 
371 	if (ctx->netdev->mtu != (ctx->max_datagram_size - ETH_HLEN))
372 		ctx->netdev->mtu = ctx->max_datagram_size - ETH_HLEN;
373 
374 	return 0;
375 }
376 
377 static void
378 cdc_ncm_find_endpoints(struct cdc_ncm_ctx *ctx, struct usb_interface *intf)
379 {
380 	struct usb_host_endpoint *e;
381 	u8 ep;
382 
383 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
384 
385 		e = intf->cur_altsetting->endpoint + ep;
386 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
387 		case USB_ENDPOINT_XFER_INT:
388 			if (usb_endpoint_dir_in(&e->desc)) {
389 				if (ctx->status_ep == NULL)
390 					ctx->status_ep = e;
391 			}
392 			break;
393 
394 		case USB_ENDPOINT_XFER_BULK:
395 			if (usb_endpoint_dir_in(&e->desc)) {
396 				if (ctx->in_ep == NULL)
397 					ctx->in_ep = e;
398 			} else {
399 				if (ctx->out_ep == NULL)
400 					ctx->out_ep = e;
401 			}
402 			break;
403 
404 		default:
405 			break;
406 		}
407 	}
408 }
409 
410 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
411 {
412 	if (ctx == NULL)
413 		return;
414 
415 	del_timer_sync(&ctx->tx_timer);
416 
417 	if (ctx->tx_rem_skb != NULL) {
418 		dev_kfree_skb_any(ctx->tx_rem_skb);
419 		ctx->tx_rem_skb = NULL;
420 	}
421 
422 	if (ctx->tx_curr_skb != NULL) {
423 		dev_kfree_skb_any(ctx->tx_curr_skb);
424 		ctx->tx_curr_skb = NULL;
425 	}
426 
427 	kfree(ctx);
428 }
429 
430 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
431 {
432 	struct cdc_ncm_ctx *ctx;
433 	struct usb_driver *driver;
434 	u8 *buf;
435 	int len;
436 	int temp;
437 	u8 iface_no;
438 
439 	ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
440 	if (ctx == NULL)
441 		return -ENODEV;
442 
443 	memset(ctx, 0, sizeof(*ctx));
444 
445 	init_timer(&ctx->tx_timer);
446 	spin_lock_init(&ctx->mtx);
447 	ctx->netdev = dev->net;
448 
449 	/* store ctx pointer in device data field */
450 	dev->data[0] = (unsigned long)ctx;
451 
452 	/* get some pointers */
453 	driver = driver_of(intf);
454 	buf = intf->cur_altsetting->extra;
455 	len = intf->cur_altsetting->extralen;
456 
457 	ctx->udev = dev->udev;
458 	ctx->intf = intf;
459 
460 	/* parse through descriptors associated with control interface */
461 	while ((len > 0) && (buf[0] > 2) && (buf[0] <= len)) {
462 
463 		if (buf[1] != USB_DT_CS_INTERFACE)
464 			goto advance;
465 
466 		switch (buf[2]) {
467 		case USB_CDC_UNION_TYPE:
468 			if (buf[0] < sizeof(*(ctx->union_desc)))
469 				break;
470 
471 			ctx->union_desc =
472 					(const struct usb_cdc_union_desc *)buf;
473 
474 			ctx->control = usb_ifnum_to_if(dev->udev,
475 					ctx->union_desc->bMasterInterface0);
476 			ctx->data = usb_ifnum_to_if(dev->udev,
477 					ctx->union_desc->bSlaveInterface0);
478 			break;
479 
480 		case USB_CDC_ETHERNET_TYPE:
481 			if (buf[0] < sizeof(*(ctx->ether_desc)))
482 				break;
483 
484 			ctx->ether_desc =
485 					(const struct usb_cdc_ether_desc *)buf;
486 			dev->hard_mtu =
487 				le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
488 
489 			if (dev->hard_mtu < CDC_NCM_MIN_DATAGRAM_SIZE)
490 				dev->hard_mtu =	CDC_NCM_MIN_DATAGRAM_SIZE;
491 			else if (dev->hard_mtu > CDC_NCM_MAX_DATAGRAM_SIZE)
492 				dev->hard_mtu =	CDC_NCM_MAX_DATAGRAM_SIZE;
493 			break;
494 
495 		case USB_CDC_NCM_TYPE:
496 			if (buf[0] < sizeof(*(ctx->func_desc)))
497 				break;
498 
499 			ctx->func_desc = (const struct usb_cdc_ncm_desc *)buf;
500 			break;
501 
502 		default:
503 			break;
504 		}
505 advance:
506 		/* advance to next descriptor */
507 		temp = buf[0];
508 		buf += temp;
509 		len -= temp;
510 	}
511 
512 	/* check if we got everything */
513 	if ((ctx->control == NULL) || (ctx->data == NULL) ||
514 	    (ctx->ether_desc == NULL) || (ctx->control != intf))
515 		goto error;
516 
517 	/* claim interfaces, if any */
518 	temp = usb_driver_claim_interface(driver, ctx->data, dev);
519 	if (temp)
520 		goto error;
521 
522 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
523 
524 	/* reset data interface */
525 	temp = usb_set_interface(dev->udev, iface_no, 0);
526 	if (temp)
527 		goto error2;
528 
529 	/* initialize data interface */
530 	if (cdc_ncm_setup(ctx))
531 		goto error2;
532 
533 	/* configure data interface */
534 	temp = usb_set_interface(dev->udev, iface_no, 1);
535 	if (temp)
536 		goto error2;
537 
538 	cdc_ncm_find_endpoints(ctx, ctx->data);
539 	cdc_ncm_find_endpoints(ctx, ctx->control);
540 
541 	if ((ctx->in_ep == NULL) || (ctx->out_ep == NULL) ||
542 	    (ctx->status_ep == NULL))
543 		goto error2;
544 
545 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
546 
547 	usb_set_intfdata(ctx->data, dev);
548 	usb_set_intfdata(ctx->control, dev);
549 	usb_set_intfdata(ctx->intf, dev);
550 
551 	temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
552 	if (temp)
553 		goto error2;
554 
555 	dev_info(&dev->udev->dev, "MAC-Address: "
556 				"0x%02x:0x%02x:0x%02x:0x%02x:0x%02x:0x%02x\n",
557 				dev->net->dev_addr[0], dev->net->dev_addr[1],
558 				dev->net->dev_addr[2], dev->net->dev_addr[3],
559 				dev->net->dev_addr[4], dev->net->dev_addr[5]);
560 
561 	dev->in = usb_rcvbulkpipe(dev->udev,
562 		ctx->in_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
563 	dev->out = usb_sndbulkpipe(dev->udev,
564 		ctx->out_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
565 	dev->status = ctx->status_ep;
566 	dev->rx_urb_size = ctx->rx_max;
567 
568 	/*
569 	 * We should get an event when network connection is "connected" or
570 	 * "disconnected". Set network connection in "disconnected" state
571 	 * (carrier is OFF) during attach, so the IP network stack does not
572 	 * start IPv6 negotiation and more.
573 	 */
574 	netif_carrier_off(dev->net);
575 	ctx->tx_speed = ctx->rx_speed = 0;
576 	return 0;
577 
578 error2:
579 	usb_set_intfdata(ctx->control, NULL);
580 	usb_set_intfdata(ctx->data, NULL);
581 	usb_driver_release_interface(driver, ctx->data);
582 error:
583 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
584 	dev->data[0] = 0;
585 	dev_info(&dev->udev->dev, "bind() failure\n");
586 	return -ENODEV;
587 }
588 
589 static void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
590 {
591 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
592 	struct usb_driver *driver = driver_of(intf);
593 
594 	if (ctx == NULL)
595 		return;		/* no setup */
596 
597 	/* disconnect master --> disconnect slave */
598 	if (intf == ctx->control && ctx->data) {
599 		usb_set_intfdata(ctx->data, NULL);
600 		usb_driver_release_interface(driver, ctx->data);
601 		ctx->data = NULL;
602 
603 	} else if (intf == ctx->data && ctx->control) {
604 		usb_set_intfdata(ctx->control, NULL);
605 		usb_driver_release_interface(driver, ctx->control);
606 		ctx->control = NULL;
607 	}
608 
609 	usb_set_intfdata(ctx->intf, NULL);
610 	cdc_ncm_free(ctx);
611 }
612 
613 static void cdc_ncm_zero_fill(u8 *ptr, u32 first, u32 end, u32 max)
614 {
615 	if (first >= max)
616 		return;
617 	if (first >= end)
618 		return;
619 	if (end > max)
620 		end = max;
621 	memset(ptr + first, 0, end - first);
622 }
623 
624 static struct sk_buff *
625 cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx *ctx, struct sk_buff *skb)
626 {
627 	struct sk_buff *skb_out;
628 	u32 rem;
629 	u32 offset;
630 	u32 last_offset;
631 	u16 n = 0, index;
632 	u8 ready2send = 0;
633 
634 	/* if there is a remaining skb, it gets priority */
635 	if (skb != NULL)
636 		swap(skb, ctx->tx_rem_skb);
637 	else
638 		ready2send = 1;
639 
640 	/*
641 	 * +----------------+
642 	 * | skb_out        |
643 	 * +----------------+
644 	 *           ^ offset
645 	 *        ^ last_offset
646 	 */
647 
648 	/* check if we are resuming an OUT skb */
649 	if (ctx->tx_curr_skb != NULL) {
650 		/* pop variables */
651 		skb_out = ctx->tx_curr_skb;
652 		offset = ctx->tx_curr_offset;
653 		last_offset = ctx->tx_curr_last_offset;
654 		n = ctx->tx_curr_frame_num;
655 
656 	} else {
657 		/* reset variables */
658 		skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
659 		if (skb_out == NULL) {
660 			if (skb != NULL) {
661 				dev_kfree_skb_any(skb);
662 				ctx->netdev->stats.tx_dropped++;
663 			}
664 			goto exit_no_skb;
665 		}
666 
667 		/* make room for NTH and NDP */
668 		offset = ALIGN(sizeof(struct usb_cdc_ncm_nth16),
669 					ctx->tx_ndp_modulus) +
670 					sizeof(struct usb_cdc_ncm_ndp16) +
671 					(ctx->tx_max_datagrams + 1) *
672 					sizeof(struct usb_cdc_ncm_dpe16);
673 
674 		/* store last valid offset before alignment */
675 		last_offset = offset;
676 		/* align first Datagram offset correctly */
677 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
678 		/* zero buffer till the first IP datagram */
679 		cdc_ncm_zero_fill(skb_out->data, 0, offset, offset);
680 		n = 0;
681 		ctx->tx_curr_frame_num = 0;
682 	}
683 
684 	for (; n < ctx->tx_max_datagrams; n++) {
685 		/* check if end of transmit buffer is reached */
686 		if (offset >= ctx->tx_max) {
687 			ready2send = 1;
688 			break;
689 		}
690 		/* compute maximum buffer size */
691 		rem = ctx->tx_max - offset;
692 
693 		if (skb == NULL) {
694 			skb = ctx->tx_rem_skb;
695 			ctx->tx_rem_skb = NULL;
696 
697 			/* check for end of skb */
698 			if (skb == NULL)
699 				break;
700 		}
701 
702 		if (skb->len > rem) {
703 			if (n == 0) {
704 				/* won't fit, MTU problem? */
705 				dev_kfree_skb_any(skb);
706 				skb = NULL;
707 				ctx->netdev->stats.tx_dropped++;
708 			} else {
709 				/* no room for skb - store for later */
710 				if (ctx->tx_rem_skb != NULL) {
711 					dev_kfree_skb_any(ctx->tx_rem_skb);
712 					ctx->netdev->stats.tx_dropped++;
713 				}
714 				ctx->tx_rem_skb = skb;
715 				skb = NULL;
716 				ready2send = 1;
717 			}
718 			break;
719 		}
720 
721 		memcpy(((u8 *)skb_out->data) + offset, skb->data, skb->len);
722 
723 		ctx->tx_ncm.dpe16[n].wDatagramLength = cpu_to_le16(skb->len);
724 		ctx->tx_ncm.dpe16[n].wDatagramIndex = cpu_to_le16(offset);
725 
726 		/* update offset */
727 		offset += skb->len;
728 
729 		/* store last valid offset before alignment */
730 		last_offset = offset;
731 
732 		/* align offset correctly */
733 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
734 
735 		/* zero padding */
736 		cdc_ncm_zero_fill(skb_out->data, last_offset, offset,
737 								ctx->tx_max);
738 		dev_kfree_skb_any(skb);
739 		skb = NULL;
740 	}
741 
742 	/* free up any dangling skb */
743 	if (skb != NULL) {
744 		dev_kfree_skb_any(skb);
745 		skb = NULL;
746 		ctx->netdev->stats.tx_dropped++;
747 	}
748 
749 	ctx->tx_curr_frame_num = n;
750 
751 	if (n == 0) {
752 		/* wait for more frames */
753 		/* push variables */
754 		ctx->tx_curr_skb = skb_out;
755 		ctx->tx_curr_offset = offset;
756 		ctx->tx_curr_last_offset = last_offset;
757 		goto exit_no_skb;
758 
759 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
760 		/* wait for more frames */
761 		/* push variables */
762 		ctx->tx_curr_skb = skb_out;
763 		ctx->tx_curr_offset = offset;
764 		ctx->tx_curr_last_offset = last_offset;
765 		/* set the pending count */
766 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
767 			ctx->tx_timer_pending = 2;
768 		goto exit_no_skb;
769 
770 	} else {
771 		/* frame goes out */
772 		/* variables will be reset at next call */
773 	}
774 
775 	/* check for overflow */
776 	if (last_offset > ctx->tx_max)
777 		last_offset = ctx->tx_max;
778 
779 	/* revert offset */
780 	offset = last_offset;
781 
782 	/*
783 	 * If collected data size is less or equal CDC_NCM_MIN_TX_PKT bytes,
784 	 * we send buffers as it is. If we get more data, it would be more
785 	 * efficient for USB HS mobile device with DMA engine to receive a full
786 	 * size NTB, than canceling DMA transfer and receiving a short packet.
787 	 */
788 	if (offset > CDC_NCM_MIN_TX_PKT)
789 		offset = ctx->tx_max;
790 
791 	/* final zero padding */
792 	cdc_ncm_zero_fill(skb_out->data, last_offset, offset, ctx->tx_max);
793 
794 	/* store last offset */
795 	last_offset = offset;
796 
797 	if (((last_offset < ctx->tx_max) && ((last_offset %
798 			le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) ||
799 	    (((last_offset == ctx->tx_max) && ((ctx->tx_max %
800 		le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) &&
801 		(ctx->tx_max < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)))) {
802 		/* force short packet */
803 		*(((u8 *)skb_out->data) + last_offset) = 0;
804 		last_offset++;
805 	}
806 
807 	/* zero the rest of the DPEs plus the last NULL entry */
808 	for (; n <= CDC_NCM_DPT_DATAGRAMS_MAX; n++) {
809 		ctx->tx_ncm.dpe16[n].wDatagramLength = 0;
810 		ctx->tx_ncm.dpe16[n].wDatagramIndex = 0;
811 	}
812 
813 	/* fill out 16-bit NTB header */
814 	ctx->tx_ncm.nth16.dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
815 	ctx->tx_ncm.nth16.wHeaderLength =
816 					cpu_to_le16(sizeof(ctx->tx_ncm.nth16));
817 	ctx->tx_ncm.nth16.wSequence = cpu_to_le16(ctx->tx_seq);
818 	ctx->tx_ncm.nth16.wBlockLength = cpu_to_le16(last_offset);
819 	index = ALIGN(sizeof(struct usb_cdc_ncm_nth16), ctx->tx_ndp_modulus);
820 	ctx->tx_ncm.nth16.wNdpIndex = cpu_to_le16(index);
821 
822 	memcpy(skb_out->data, &(ctx->tx_ncm.nth16), sizeof(ctx->tx_ncm.nth16));
823 	ctx->tx_seq++;
824 
825 	/* fill out 16-bit NDP table */
826 	ctx->tx_ncm.ndp16.dwSignature =
827 				cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN);
828 	rem = sizeof(ctx->tx_ncm.ndp16) + ((ctx->tx_curr_frame_num + 1) *
829 					sizeof(struct usb_cdc_ncm_dpe16));
830 	ctx->tx_ncm.ndp16.wLength = cpu_to_le16(rem);
831 	ctx->tx_ncm.ndp16.wNextNdpIndex = 0; /* reserved */
832 
833 	memcpy(((u8 *)skb_out->data) + index,
834 						&(ctx->tx_ncm.ndp16),
835 						sizeof(ctx->tx_ncm.ndp16));
836 
837 	memcpy(((u8 *)skb_out->data) + index + sizeof(ctx->tx_ncm.ndp16),
838 					&(ctx->tx_ncm.dpe16),
839 					(ctx->tx_curr_frame_num + 1) *
840 					sizeof(struct usb_cdc_ncm_dpe16));
841 
842 	/* set frame length */
843 	skb_put(skb_out, last_offset);
844 
845 	/* return skb */
846 	ctx->tx_curr_skb = NULL;
847 	return skb_out;
848 
849 exit_no_skb:
850 	return NULL;
851 }
852 
853 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
854 {
855 	/* start timer, if not already started */
856 	if (timer_pending(&ctx->tx_timer) == 0) {
857 		ctx->tx_timer.function = &cdc_ncm_tx_timeout;
858 		ctx->tx_timer.data = (unsigned long)ctx;
859 		ctx->tx_timer.expires = jiffies + ((HZ + 999) / 1000);
860 		add_timer(&ctx->tx_timer);
861 	}
862 }
863 
864 static void cdc_ncm_tx_timeout(unsigned long arg)
865 {
866 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)arg;
867 	u8 restart;
868 
869 	spin_lock(&ctx->mtx);
870 	if (ctx->tx_timer_pending != 0) {
871 		ctx->tx_timer_pending--;
872 		restart = 1;
873 	} else {
874 		restart = 0;
875 	}
876 
877 	spin_unlock(&ctx->mtx);
878 
879 	if (restart) {
880 		spin_lock(&ctx->mtx);
881 		cdc_ncm_tx_timeout_start(ctx);
882 		spin_unlock(&ctx->mtx);
883 	} else if (ctx->netdev != NULL) {
884 		usbnet_start_xmit(NULL, ctx->netdev);
885 	}
886 }
887 
888 static struct sk_buff *
889 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
890 {
891 	struct sk_buff *skb_out;
892 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
893 	u8 need_timer = 0;
894 
895 	/*
896 	 * The Ethernet API we are using does not support transmitting
897 	 * multiple Ethernet frames in a single call. This driver will
898 	 * accumulate multiple Ethernet frames and send out a larger
899 	 * USB frame when the USB buffer is full or when a single jiffies
900 	 * timeout happens.
901 	 */
902 	if (ctx == NULL)
903 		goto error;
904 
905 	spin_lock(&ctx->mtx);
906 	skb_out = cdc_ncm_fill_tx_frame(ctx, skb);
907 	if (ctx->tx_curr_skb != NULL)
908 		need_timer = 1;
909 
910 	/* Start timer, if there is a remaining skb */
911 	if (need_timer)
912 		cdc_ncm_tx_timeout_start(ctx);
913 
914 	if (skb_out)
915 		dev->net->stats.tx_packets += ctx->tx_curr_frame_num;
916 
917 	spin_unlock(&ctx->mtx);
918 	return skb_out;
919 
920 error:
921 	if (skb != NULL)
922 		dev_kfree_skb_any(skb);
923 
924 	return NULL;
925 }
926 
927 static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
928 {
929 	struct sk_buff *skb;
930 	struct cdc_ncm_ctx *ctx;
931 	int sumlen;
932 	int actlen;
933 	int temp;
934 	int nframes;
935 	int x;
936 	int offset;
937 
938 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
939 	if (ctx == NULL)
940 		goto error;
941 
942 	actlen = skb_in->len;
943 	sumlen = CDC_NCM_NTB_MAX_SIZE_RX;
944 
945 	if (actlen < (sizeof(ctx->rx_ncm.nth16) + sizeof(ctx->rx_ncm.ndp16))) {
946 		pr_debug("frame too short\n");
947 		goto error;
948 	}
949 
950 	memcpy(&(ctx->rx_ncm.nth16), ((u8 *)skb_in->data),
951 						sizeof(ctx->rx_ncm.nth16));
952 
953 	if (le32_to_cpu(ctx->rx_ncm.nth16.dwSignature) !=
954 	    USB_CDC_NCM_NTH16_SIGN) {
955 		pr_debug("invalid NTH16 signature <%u>\n",
956 			 le32_to_cpu(ctx->rx_ncm.nth16.dwSignature));
957 		goto error;
958 	}
959 
960 	temp = le16_to_cpu(ctx->rx_ncm.nth16.wBlockLength);
961 	if (temp > sumlen) {
962 		pr_debug("unsupported NTB block length %u/%u\n", temp, sumlen);
963 		goto error;
964 	}
965 
966 	temp = le16_to_cpu(ctx->rx_ncm.nth16.wNdpIndex);
967 	if ((temp + sizeof(ctx->rx_ncm.ndp16)) > actlen) {
968 		pr_debug("invalid DPT16 index\n");
969 		goto error;
970 	}
971 
972 	memcpy(&(ctx->rx_ncm.ndp16), ((u8 *)skb_in->data) + temp,
973 						sizeof(ctx->rx_ncm.ndp16));
974 
975 	if (le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature) !=
976 	    USB_CDC_NCM_NDP16_NOCRC_SIGN) {
977 		pr_debug("invalid DPT16 signature <%u>\n",
978 			 le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature));
979 		goto error;
980 	}
981 
982 	if (le16_to_cpu(ctx->rx_ncm.ndp16.wLength) <
983 	    USB_CDC_NCM_NDP16_LENGTH_MIN) {
984 		pr_debug("invalid DPT16 length <%u>\n",
985 			 le32_to_cpu(ctx->rx_ncm.ndp16.dwSignature));
986 		goto error;
987 	}
988 
989 	nframes = ((le16_to_cpu(ctx->rx_ncm.ndp16.wLength) -
990 					sizeof(struct usb_cdc_ncm_ndp16)) /
991 					sizeof(struct usb_cdc_ncm_dpe16));
992 	nframes--; /* we process NDP entries except for the last one */
993 
994 	pr_debug("nframes = %u\n", nframes);
995 
996 	temp += sizeof(ctx->rx_ncm.ndp16);
997 
998 	if ((temp + nframes * (sizeof(struct usb_cdc_ncm_dpe16))) > actlen) {
999 		pr_debug("Invalid nframes = %d\n", nframes);
1000 		goto error;
1001 	}
1002 
1003 	if (nframes > CDC_NCM_DPT_DATAGRAMS_MAX) {
1004 		pr_debug("Truncating number of frames from %u to %u\n",
1005 					nframes, CDC_NCM_DPT_DATAGRAMS_MAX);
1006 		nframes = CDC_NCM_DPT_DATAGRAMS_MAX;
1007 	}
1008 
1009 	memcpy(&(ctx->rx_ncm.dpe16), ((u8 *)skb_in->data) + temp,
1010 				nframes * (sizeof(struct usb_cdc_ncm_dpe16)));
1011 
1012 	for (x = 0; x < nframes; x++) {
1013 		offset = le16_to_cpu(ctx->rx_ncm.dpe16[x].wDatagramIndex);
1014 		temp = le16_to_cpu(ctx->rx_ncm.dpe16[x].wDatagramLength);
1015 
1016 		/*
1017 		 * CDC NCM ch. 3.7
1018 		 * All entries after first NULL entry are to be ignored
1019 		 */
1020 		if ((offset == 0) || (temp == 0)) {
1021 			if (!x)
1022 				goto error; /* empty NTB */
1023 			break;
1024 		}
1025 
1026 		/* sanity checking */
1027 		if (((offset + temp) > actlen) ||
1028 		    (temp > CDC_NCM_MAX_DATAGRAM_SIZE) || (temp < ETH_HLEN)) {
1029 			pr_debug("invalid frame detected (ignored)"
1030 					"offset[%u]=%u, length=%u, skb=%p\n",
1031 					x, offset, temp, skb_in);
1032 			if (!x)
1033 				goto error;
1034 			break;
1035 
1036 		} else {
1037 			skb = skb_clone(skb_in, GFP_ATOMIC);
1038 			if (!skb)
1039 				goto error;
1040 			skb->len = temp;
1041 			skb->data = ((u8 *)skb_in->data) + offset;
1042 			skb_set_tail_pointer(skb, temp);
1043 			usbnet_skb_return(dev, skb);
1044 		}
1045 	}
1046 	return 1;
1047 error:
1048 	return 0;
1049 }
1050 
1051 static void
1052 cdc_ncm_speed_change(struct cdc_ncm_ctx *ctx,
1053 		     struct usb_cdc_speed_change *data)
1054 {
1055 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1056 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1057 
1058 	/*
1059 	 * Currently the USB-NET API does not support reporting the actual
1060 	 * device speed. Do print it instead.
1061 	 */
1062 	if ((tx_speed != ctx->tx_speed) || (rx_speed != ctx->rx_speed)) {
1063 		ctx->tx_speed = tx_speed;
1064 		ctx->rx_speed = rx_speed;
1065 
1066 		if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1067 			printk(KERN_INFO KBUILD_MODNAME
1068 				": %s: %u mbit/s downlink "
1069 				"%u mbit/s uplink\n",
1070 				ctx->netdev->name,
1071 				(unsigned int)(rx_speed / 1000000U),
1072 				(unsigned int)(tx_speed / 1000000U));
1073 		} else {
1074 			printk(KERN_INFO KBUILD_MODNAME
1075 				": %s: %u kbit/s downlink "
1076 				"%u kbit/s uplink\n",
1077 				ctx->netdev->name,
1078 				(unsigned int)(rx_speed / 1000U),
1079 				(unsigned int)(tx_speed / 1000U));
1080 		}
1081 	}
1082 }
1083 
1084 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1085 {
1086 	struct cdc_ncm_ctx *ctx;
1087 	struct usb_cdc_notification *event;
1088 
1089 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1090 
1091 	if (urb->actual_length < sizeof(*event))
1092 		return;
1093 
1094 	/* test for split data in 8-byte chunks */
1095 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1096 		cdc_ncm_speed_change(ctx,
1097 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1098 		return;
1099 	}
1100 
1101 	event = urb->transfer_buffer;
1102 
1103 	switch (event->bNotificationType) {
1104 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1105 		/*
1106 		 * According to the CDC NCM specification ch.7.1
1107 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1108 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1109 		 */
1110 		ctx->connected = event->wValue;
1111 
1112 		printk(KERN_INFO KBUILD_MODNAME ": %s: network connection:"
1113 			" %sconnected\n",
1114 			ctx->netdev->name, ctx->connected ? "" : "dis");
1115 
1116 		if (ctx->connected)
1117 			netif_carrier_on(dev->net);
1118 		else {
1119 			netif_carrier_off(dev->net);
1120 			ctx->tx_speed = ctx->rx_speed = 0;
1121 		}
1122 		break;
1123 
1124 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1125 		if (urb->actual_length < (sizeof(*event) +
1126 					sizeof(struct usb_cdc_speed_change)))
1127 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1128 		else
1129 			cdc_ncm_speed_change(ctx,
1130 				(struct usb_cdc_speed_change *) &event[1]);
1131 		break;
1132 
1133 	default:
1134 		dev_err(&dev->udev->dev, "NCM: unexpected "
1135 			"notification 0x%02x!\n", event->bNotificationType);
1136 		break;
1137 	}
1138 }
1139 
1140 static int cdc_ncm_check_connect(struct usbnet *dev)
1141 {
1142 	struct cdc_ncm_ctx *ctx;
1143 
1144 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1145 	if (ctx == NULL)
1146 		return 1;	/* disconnected */
1147 
1148 	return !ctx->connected;
1149 }
1150 
1151 static int
1152 cdc_ncm_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1153 {
1154 	return usbnet_probe(udev, prod);
1155 }
1156 
1157 static void cdc_ncm_disconnect(struct usb_interface *intf)
1158 {
1159 	struct usbnet *dev = usb_get_intfdata(intf);
1160 
1161 	if (dev == NULL)
1162 		return;		/* already disconnected */
1163 
1164 	usbnet_disconnect(intf);
1165 }
1166 
1167 static int cdc_ncm_manage_power(struct usbnet *dev, int status)
1168 {
1169 	dev->intf->needs_remote_wakeup = status;
1170 	return 0;
1171 }
1172 
1173 static const struct driver_info cdc_ncm_info = {
1174 	.description = "CDC NCM",
1175 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET,
1176 	.bind = cdc_ncm_bind,
1177 	.unbind = cdc_ncm_unbind,
1178 	.check_connect = cdc_ncm_check_connect,
1179 	.manage_power = cdc_ncm_manage_power,
1180 	.status = cdc_ncm_status,
1181 	.rx_fixup = cdc_ncm_rx_fixup,
1182 	.tx_fixup = cdc_ncm_tx_fixup,
1183 };
1184 
1185 static struct usb_driver cdc_ncm_driver = {
1186 	.name = "cdc_ncm",
1187 	.id_table = cdc_devs,
1188 	.probe = cdc_ncm_probe,
1189 	.disconnect = cdc_ncm_disconnect,
1190 	.suspend = usbnet_suspend,
1191 	.resume = usbnet_resume,
1192 	.reset_resume =	usbnet_resume,
1193 	.supports_autosuspend = 1,
1194 };
1195 
1196 static struct ethtool_ops cdc_ncm_ethtool_ops = {
1197 	.get_drvinfo = cdc_ncm_get_drvinfo,
1198 	.get_link = usbnet_get_link,
1199 	.get_msglevel = usbnet_get_msglevel,
1200 	.set_msglevel = usbnet_set_msglevel,
1201 	.get_settings = usbnet_get_settings,
1202 	.set_settings = usbnet_set_settings,
1203 	.nway_reset = usbnet_nway_reset,
1204 };
1205 
1206 static int __init cdc_ncm_init(void)
1207 {
1208 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION "\n");
1209 	return usb_register(&cdc_ncm_driver);
1210 }
1211 
1212 module_init(cdc_ncm_init);
1213 
1214 static void __exit cdc_ncm_exit(void)
1215 {
1216 	usb_deregister(&cdc_ncm_driver);
1217 }
1218 
1219 module_exit(cdc_ncm_exit);
1220 
1221 MODULE_AUTHOR("Hans Petter Selasky");
1222 MODULE_DESCRIPTION("USB CDC NCM host driver");
1223 MODULE_LICENSE("Dual BSD/GPL");
1224