xref: /openbmc/linux/drivers/net/usb/cdc_ncm.c (revision 95e9fd10)
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/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/hrtimer.h>
51 #include <linux/atomic.h>
52 #include <linux/usb/usbnet.h>
53 #include <linux/usb/cdc.h>
54 
55 #define	DRIVER_VERSION				"14-Mar-2012"
56 
57 /* CDC NCM subclass 3.2.1 */
58 #define USB_CDC_NCM_NDP16_LENGTH_MIN		0x10
59 
60 /* Maximum NTB length */
61 #define	CDC_NCM_NTB_MAX_SIZE_TX			32768	/* bytes */
62 #define	CDC_NCM_NTB_MAX_SIZE_RX			32768	/* bytes */
63 
64 /* Minimum value for MaxDatagramSize, ch. 6.2.9 */
65 #define	CDC_NCM_MIN_DATAGRAM_SIZE		1514	/* bytes */
66 
67 #define	CDC_NCM_MIN_TX_PKT			512	/* bytes */
68 
69 /* Default value for MaxDatagramSize */
70 #define	CDC_NCM_MAX_DATAGRAM_SIZE		8192	/* bytes */
71 
72 /*
73  * Maximum amount of datagrams in NCM Datagram Pointer Table, not counting
74  * the last NULL entry.
75  */
76 #define	CDC_NCM_DPT_DATAGRAMS_MAX		40
77 
78 /* Restart the timer, if amount of datagrams is less than given value */
79 #define	CDC_NCM_RESTART_TIMER_DATAGRAM_CNT	3
80 #define	CDC_NCM_TIMER_PENDING_CNT		2
81 #define CDC_NCM_TIMER_INTERVAL			(400UL * NSEC_PER_USEC)
82 
83 /* The following macro defines the minimum header space */
84 #define	CDC_NCM_MIN_HDR_SIZE \
85 	(sizeof(struct usb_cdc_ncm_nth16) + sizeof(struct usb_cdc_ncm_ndp16) + \
86 	(CDC_NCM_DPT_DATAGRAMS_MAX + 1) * sizeof(struct usb_cdc_ncm_dpe16))
87 
88 struct cdc_ncm_data {
89 	struct usb_cdc_ncm_nth16 nth16;
90 	struct usb_cdc_ncm_ndp16 ndp16;
91 	struct usb_cdc_ncm_dpe16 dpe16[CDC_NCM_DPT_DATAGRAMS_MAX + 1];
92 };
93 
94 struct cdc_ncm_ctx {
95 	struct cdc_ncm_data tx_ncm;
96 	struct usb_cdc_ncm_ntb_parameters ncm_parm;
97 	struct hrtimer tx_timer;
98 	struct tasklet_struct bh;
99 
100 	const struct usb_cdc_ncm_desc *func_desc;
101 	const struct usb_cdc_header_desc *header_desc;
102 	const struct usb_cdc_union_desc *union_desc;
103 	const struct usb_cdc_ether_desc *ether_desc;
104 
105 	struct net_device *netdev;
106 	struct usb_device *udev;
107 	struct usb_host_endpoint *in_ep;
108 	struct usb_host_endpoint *out_ep;
109 	struct usb_host_endpoint *status_ep;
110 	struct usb_interface *intf;
111 	struct usb_interface *control;
112 	struct usb_interface *data;
113 
114 	struct sk_buff *tx_curr_skb;
115 	struct sk_buff *tx_rem_skb;
116 
117 	spinlock_t mtx;
118 	atomic_t stop;
119 
120 	u32 tx_timer_pending;
121 	u32 tx_curr_offset;
122 	u32 tx_curr_last_offset;
123 	u32 tx_curr_frame_num;
124 	u32 rx_speed;
125 	u32 tx_speed;
126 	u32 rx_max;
127 	u32 tx_max;
128 	u32 max_datagram_size;
129 	u16 tx_max_datagrams;
130 	u16 tx_remainder;
131 	u16 tx_modulus;
132 	u16 tx_ndp_modulus;
133 	u16 tx_seq;
134 	u16 rx_seq;
135 	u16 connected;
136 };
137 
138 static void cdc_ncm_txpath_bh(unsigned long param);
139 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
140 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
141 static struct usb_driver cdc_ncm_driver;
142 
143 static void
144 cdc_ncm_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
145 {
146 	struct usbnet *dev = netdev_priv(net);
147 
148 	strncpy(info->driver, dev->driver_name, sizeof(info->driver));
149 	strncpy(info->version, DRIVER_VERSION, sizeof(info->version));
150 	strncpy(info->fw_version, dev->driver_info->description,
151 		sizeof(info->fw_version));
152 	usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
153 }
154 
155 static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
156 {
157 	u32 val;
158 	u8 flags;
159 	u8 iface_no;
160 	int err;
161 	u16 ntb_fmt_supported;
162 
163 	iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
164 
165 	err = usb_control_msg(ctx->udev,
166 				usb_rcvctrlpipe(ctx->udev, 0),
167 				USB_CDC_GET_NTB_PARAMETERS,
168 				USB_TYPE_CLASS | USB_DIR_IN
169 				 | USB_RECIP_INTERFACE,
170 				0, iface_no, &ctx->ncm_parm,
171 				sizeof(ctx->ncm_parm), 10000);
172 	if (err < 0) {
173 		pr_debug("failed GET_NTB_PARAMETERS\n");
174 		return 1;
175 	}
176 
177 	/* read correct set of parameters according to device mode */
178 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
179 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
180 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
181 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
182 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
183 	/* devices prior to NCM Errata shall set this field to zero */
184 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
185 	ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
186 
187 	if (ctx->func_desc != NULL)
188 		flags = ctx->func_desc->bmNetworkCapabilities;
189 	else
190 		flags = 0;
191 
192 	pr_debug("dwNtbInMaxSize=%u dwNtbOutMaxSize=%u "
193 		 "wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u "
194 		 "wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
195 		 ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
196 		 ctx->tx_ndp_modulus, ctx->tx_max_datagrams, flags);
197 
198 	/* max count of tx datagrams */
199 	if ((ctx->tx_max_datagrams == 0) ||
200 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
201 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
202 
203 	/* verify maximum size of received NTB in bytes */
204 	if (ctx->rx_max < USB_CDC_NCM_NTB_MIN_IN_SIZE) {
205 		pr_debug("Using min receive length=%d\n",
206 						USB_CDC_NCM_NTB_MIN_IN_SIZE);
207 		ctx->rx_max = USB_CDC_NCM_NTB_MIN_IN_SIZE;
208 	}
209 
210 	if (ctx->rx_max > CDC_NCM_NTB_MAX_SIZE_RX) {
211 		pr_debug("Using default maximum receive length=%d\n",
212 						CDC_NCM_NTB_MAX_SIZE_RX);
213 		ctx->rx_max = CDC_NCM_NTB_MAX_SIZE_RX;
214 	}
215 
216 	/* inform device about NTB input size changes */
217 	if (ctx->rx_max != le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize)) {
218 
219 		if (flags & USB_CDC_NCM_NCAP_NTB_INPUT_SIZE) {
220 			struct usb_cdc_ncm_ndp_input_size *ndp_in_sz;
221 
222 			ndp_in_sz = kzalloc(sizeof(*ndp_in_sz), GFP_KERNEL);
223 			if (!ndp_in_sz) {
224 				err = -ENOMEM;
225 				goto size_err;
226 			}
227 
228 			err = usb_control_msg(ctx->udev,
229 					usb_sndctrlpipe(ctx->udev, 0),
230 					USB_CDC_SET_NTB_INPUT_SIZE,
231 					USB_TYPE_CLASS | USB_DIR_OUT
232 					 | USB_RECIP_INTERFACE,
233 					0, iface_no, ndp_in_sz, 8, 1000);
234 			kfree(ndp_in_sz);
235 		} else {
236 			__le32 *dwNtbInMaxSize;
237 			dwNtbInMaxSize = kzalloc(sizeof(*dwNtbInMaxSize),
238 					GFP_KERNEL);
239 			if (!dwNtbInMaxSize) {
240 				err = -ENOMEM;
241 				goto size_err;
242 			}
243 			*dwNtbInMaxSize = cpu_to_le32(ctx->rx_max);
244 
245 			err = usb_control_msg(ctx->udev,
246 					usb_sndctrlpipe(ctx->udev, 0),
247 					USB_CDC_SET_NTB_INPUT_SIZE,
248 					USB_TYPE_CLASS | USB_DIR_OUT
249 					 | USB_RECIP_INTERFACE,
250 					0, iface_no, dwNtbInMaxSize, 4, 1000);
251 			kfree(dwNtbInMaxSize);
252 		}
253 size_err:
254 		if (err < 0)
255 			pr_debug("Setting NTB Input Size failed\n");
256 	}
257 
258 	/* verify maximum size of transmitted NTB in bytes */
259 	if ((ctx->tx_max <
260 	    (CDC_NCM_MIN_HDR_SIZE + CDC_NCM_MIN_DATAGRAM_SIZE)) ||
261 	    (ctx->tx_max > CDC_NCM_NTB_MAX_SIZE_TX)) {
262 		pr_debug("Using default maximum transmit length=%d\n",
263 						CDC_NCM_NTB_MAX_SIZE_TX);
264 		ctx->tx_max = CDC_NCM_NTB_MAX_SIZE_TX;
265 	}
266 
267 	/*
268 	 * verify that the structure alignment is:
269 	 * - power of two
270 	 * - not greater than the maximum transmit length
271 	 * - not less than four bytes
272 	 */
273 	val = ctx->tx_ndp_modulus;
274 
275 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
276 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
277 		pr_debug("Using default alignment: 4 bytes\n");
278 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
279 	}
280 
281 	/*
282 	 * verify that the payload alignment is:
283 	 * - power of two
284 	 * - not greater than the maximum transmit length
285 	 * - not less than four bytes
286 	 */
287 	val = ctx->tx_modulus;
288 
289 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
290 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
291 		pr_debug("Using default transmit modulus: 4 bytes\n");
292 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
293 	}
294 
295 	/* verify the payload remainder */
296 	if (ctx->tx_remainder >= ctx->tx_modulus) {
297 		pr_debug("Using default transmit remainder: 0 bytes\n");
298 		ctx->tx_remainder = 0;
299 	}
300 
301 	/* adjust TX-remainder according to NCM specification. */
302 	ctx->tx_remainder = ((ctx->tx_remainder - ETH_HLEN) &
303 						(ctx->tx_modulus - 1));
304 
305 	/* additional configuration */
306 
307 	/* set CRC Mode */
308 	if (flags & USB_CDC_NCM_NCAP_CRC_MODE) {
309 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
310 				USB_CDC_SET_CRC_MODE,
311 				USB_TYPE_CLASS | USB_DIR_OUT
312 				 | USB_RECIP_INTERFACE,
313 				USB_CDC_NCM_CRC_NOT_APPENDED,
314 				iface_no, NULL, 0, 1000);
315 		if (err < 0)
316 			pr_debug("Setting CRC mode off failed\n");
317 	}
318 
319 	/* set NTB format, if both formats are supported */
320 	if (ntb_fmt_supported & USB_CDC_NCM_NTH32_SIGN) {
321 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
322 				USB_CDC_SET_NTB_FORMAT, USB_TYPE_CLASS
323 				 | USB_DIR_OUT | USB_RECIP_INTERFACE,
324 				USB_CDC_NCM_NTB16_FORMAT,
325 				iface_no, NULL, 0, 1000);
326 		if (err < 0)
327 			pr_debug("Setting NTB format to 16-bit failed\n");
328 	}
329 
330 	ctx->max_datagram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
331 
332 	/* set Max Datagram Size (MTU) */
333 	if (flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE) {
334 		__le16 *max_datagram_size;
335 		u16 eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
336 
337 		max_datagram_size = kzalloc(sizeof(*max_datagram_size),
338 				GFP_KERNEL);
339 		if (!max_datagram_size) {
340 			err = -ENOMEM;
341 			goto max_dgram_err;
342 		}
343 
344 		err = usb_control_msg(ctx->udev, usb_rcvctrlpipe(ctx->udev, 0),
345 				USB_CDC_GET_MAX_DATAGRAM_SIZE,
346 				USB_TYPE_CLASS | USB_DIR_IN
347 				 | USB_RECIP_INTERFACE,
348 				0, iface_no, max_datagram_size,
349 				2, 1000);
350 		if (err < 0) {
351 			pr_debug("GET_MAX_DATAGRAM_SIZE failed, use size=%u\n",
352 						CDC_NCM_MIN_DATAGRAM_SIZE);
353 		} else {
354 			ctx->max_datagram_size =
355 				le16_to_cpu(*max_datagram_size);
356 			/* Check Eth descriptor value */
357 			if (ctx->max_datagram_size > eth_max_sz)
358 					ctx->max_datagram_size = eth_max_sz;
359 
360 			if (ctx->max_datagram_size > CDC_NCM_MAX_DATAGRAM_SIZE)
361 				ctx->max_datagram_size =
362 						CDC_NCM_MAX_DATAGRAM_SIZE;
363 
364 			if (ctx->max_datagram_size < CDC_NCM_MIN_DATAGRAM_SIZE)
365 				ctx->max_datagram_size =
366 					CDC_NCM_MIN_DATAGRAM_SIZE;
367 
368 			/* if value changed, update device */
369 			if (ctx->max_datagram_size !=
370 					le16_to_cpu(*max_datagram_size)) {
371 				err = usb_control_msg(ctx->udev,
372 						usb_sndctrlpipe(ctx->udev, 0),
373 						USB_CDC_SET_MAX_DATAGRAM_SIZE,
374 						USB_TYPE_CLASS | USB_DIR_OUT
375 						 | USB_RECIP_INTERFACE,
376 						0,
377 						iface_no, max_datagram_size,
378 						2, 1000);
379 				if (err < 0)
380 					pr_debug("SET_MAX_DGRAM_SIZE failed\n");
381 			}
382 		}
383 		kfree(max_datagram_size);
384 	}
385 
386 max_dgram_err:
387 	if (ctx->netdev->mtu != (ctx->max_datagram_size - ETH_HLEN))
388 		ctx->netdev->mtu = ctx->max_datagram_size - ETH_HLEN;
389 
390 	return 0;
391 }
392 
393 static void
394 cdc_ncm_find_endpoints(struct cdc_ncm_ctx *ctx, struct usb_interface *intf)
395 {
396 	struct usb_host_endpoint *e;
397 	u8 ep;
398 
399 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
400 
401 		e = intf->cur_altsetting->endpoint + ep;
402 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
403 		case USB_ENDPOINT_XFER_INT:
404 			if (usb_endpoint_dir_in(&e->desc)) {
405 				if (ctx->status_ep == NULL)
406 					ctx->status_ep = e;
407 			}
408 			break;
409 
410 		case USB_ENDPOINT_XFER_BULK:
411 			if (usb_endpoint_dir_in(&e->desc)) {
412 				if (ctx->in_ep == NULL)
413 					ctx->in_ep = e;
414 			} else {
415 				if (ctx->out_ep == NULL)
416 					ctx->out_ep = e;
417 			}
418 			break;
419 
420 		default:
421 			break;
422 		}
423 	}
424 }
425 
426 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
427 {
428 	if (ctx == NULL)
429 		return;
430 
431 	if (ctx->tx_rem_skb != NULL) {
432 		dev_kfree_skb_any(ctx->tx_rem_skb);
433 		ctx->tx_rem_skb = NULL;
434 	}
435 
436 	if (ctx->tx_curr_skb != NULL) {
437 		dev_kfree_skb_any(ctx->tx_curr_skb);
438 		ctx->tx_curr_skb = NULL;
439 	}
440 
441 	kfree(ctx);
442 }
443 
444 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
445 	.get_drvinfo = cdc_ncm_get_drvinfo,
446 	.get_link = usbnet_get_link,
447 	.get_msglevel = usbnet_get_msglevel,
448 	.set_msglevel = usbnet_set_msglevel,
449 	.get_settings = usbnet_get_settings,
450 	.set_settings = usbnet_set_settings,
451 	.nway_reset = usbnet_nway_reset,
452 };
453 
454 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
455 {
456 	struct cdc_ncm_ctx *ctx;
457 	struct usb_driver *driver;
458 	u8 *buf;
459 	int len;
460 	int temp;
461 	u8 iface_no;
462 
463 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
464 	if (ctx == NULL)
465 		return -ENODEV;
466 
467 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
468 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
469 	ctx->bh.data = (unsigned long)ctx;
470 	ctx->bh.func = cdc_ncm_txpath_bh;
471 	atomic_set(&ctx->stop, 0);
472 	spin_lock_init(&ctx->mtx);
473 	ctx->netdev = dev->net;
474 
475 	/* store ctx pointer in device data field */
476 	dev->data[0] = (unsigned long)ctx;
477 
478 	/* get some pointers */
479 	driver = driver_of(intf);
480 	buf = intf->cur_altsetting->extra;
481 	len = intf->cur_altsetting->extralen;
482 
483 	ctx->udev = dev->udev;
484 	ctx->intf = intf;
485 
486 	/* parse through descriptors associated with control interface */
487 	while ((len > 0) && (buf[0] > 2) && (buf[0] <= len)) {
488 
489 		if (buf[1] != USB_DT_CS_INTERFACE)
490 			goto advance;
491 
492 		switch (buf[2]) {
493 		case USB_CDC_UNION_TYPE:
494 			if (buf[0] < sizeof(*(ctx->union_desc)))
495 				break;
496 
497 			ctx->union_desc =
498 					(const struct usb_cdc_union_desc *)buf;
499 
500 			ctx->control = usb_ifnum_to_if(dev->udev,
501 					ctx->union_desc->bMasterInterface0);
502 			ctx->data = usb_ifnum_to_if(dev->udev,
503 					ctx->union_desc->bSlaveInterface0);
504 			break;
505 
506 		case USB_CDC_ETHERNET_TYPE:
507 			if (buf[0] < sizeof(*(ctx->ether_desc)))
508 				break;
509 
510 			ctx->ether_desc =
511 					(const struct usb_cdc_ether_desc *)buf;
512 			dev->hard_mtu =
513 				le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
514 
515 			if (dev->hard_mtu < CDC_NCM_MIN_DATAGRAM_SIZE)
516 				dev->hard_mtu =	CDC_NCM_MIN_DATAGRAM_SIZE;
517 			else if (dev->hard_mtu > CDC_NCM_MAX_DATAGRAM_SIZE)
518 				dev->hard_mtu =	CDC_NCM_MAX_DATAGRAM_SIZE;
519 			break;
520 
521 		case USB_CDC_NCM_TYPE:
522 			if (buf[0] < sizeof(*(ctx->func_desc)))
523 				break;
524 
525 			ctx->func_desc = (const struct usb_cdc_ncm_desc *)buf;
526 			break;
527 
528 		default:
529 			break;
530 		}
531 advance:
532 		/* advance to next descriptor */
533 		temp = buf[0];
534 		buf += temp;
535 		len -= temp;
536 	}
537 
538 	/* check if we got everything */
539 	if ((ctx->control == NULL) || (ctx->data == NULL) ||
540 	    (ctx->ether_desc == NULL) || (ctx->control != intf))
541 		goto error;
542 
543 	/* claim interfaces, if any */
544 	temp = usb_driver_claim_interface(driver, ctx->data, dev);
545 	if (temp)
546 		goto error;
547 
548 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
549 
550 	/* reset data interface */
551 	temp = usb_set_interface(dev->udev, iface_no, 0);
552 	if (temp)
553 		goto error2;
554 
555 	/* initialize data interface */
556 	if (cdc_ncm_setup(ctx))
557 		goto error2;
558 
559 	/* configure data interface */
560 	temp = usb_set_interface(dev->udev, iface_no, 1);
561 	if (temp)
562 		goto error2;
563 
564 	cdc_ncm_find_endpoints(ctx, ctx->data);
565 	cdc_ncm_find_endpoints(ctx, ctx->control);
566 
567 	if ((ctx->in_ep == NULL) || (ctx->out_ep == NULL) ||
568 	    (ctx->status_ep == NULL))
569 		goto error2;
570 
571 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
572 
573 	usb_set_intfdata(ctx->data, dev);
574 	usb_set_intfdata(ctx->control, dev);
575 	usb_set_intfdata(ctx->intf, dev);
576 
577 	temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
578 	if (temp)
579 		goto error2;
580 
581 	dev_info(&dev->udev->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
582 
583 	dev->in = usb_rcvbulkpipe(dev->udev,
584 		ctx->in_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
585 	dev->out = usb_sndbulkpipe(dev->udev,
586 		ctx->out_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
587 	dev->status = ctx->status_ep;
588 	dev->rx_urb_size = ctx->rx_max;
589 
590 	/*
591 	 * We should get an event when network connection is "connected" or
592 	 * "disconnected". Set network connection in "disconnected" state
593 	 * (carrier is OFF) during attach, so the IP network stack does not
594 	 * start IPv6 negotiation and more.
595 	 */
596 	netif_carrier_off(dev->net);
597 	ctx->tx_speed = ctx->rx_speed = 0;
598 	return 0;
599 
600 error2:
601 	usb_set_intfdata(ctx->control, NULL);
602 	usb_set_intfdata(ctx->data, NULL);
603 	usb_driver_release_interface(driver, ctx->data);
604 error:
605 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
606 	dev->data[0] = 0;
607 	dev_info(&dev->udev->dev, "bind() failure\n");
608 	return -ENODEV;
609 }
610 
611 static void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
612 {
613 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
614 	struct usb_driver *driver = driver_of(intf);
615 
616 	if (ctx == NULL)
617 		return;		/* no setup */
618 
619 	atomic_set(&ctx->stop, 1);
620 
621 	if (hrtimer_active(&ctx->tx_timer))
622 		hrtimer_cancel(&ctx->tx_timer);
623 
624 	tasklet_kill(&ctx->bh);
625 
626 	/* disconnect master --> disconnect slave */
627 	if (intf == ctx->control && ctx->data) {
628 		usb_set_intfdata(ctx->data, NULL);
629 		usb_driver_release_interface(driver, ctx->data);
630 		ctx->data = NULL;
631 
632 	} else if (intf == ctx->data && ctx->control) {
633 		usb_set_intfdata(ctx->control, NULL);
634 		usb_driver_release_interface(driver, ctx->control);
635 		ctx->control = NULL;
636 	}
637 
638 	usb_set_intfdata(ctx->intf, NULL);
639 	cdc_ncm_free(ctx);
640 }
641 
642 static void cdc_ncm_zero_fill(u8 *ptr, u32 first, u32 end, u32 max)
643 {
644 	if (first >= max)
645 		return;
646 	if (first >= end)
647 		return;
648 	if (end > max)
649 		end = max;
650 	memset(ptr + first, 0, end - first);
651 }
652 
653 static struct sk_buff *
654 cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx *ctx, struct sk_buff *skb)
655 {
656 	struct sk_buff *skb_out;
657 	u32 rem;
658 	u32 offset;
659 	u32 last_offset;
660 	u16 n = 0, index;
661 	u8 ready2send = 0;
662 
663 	/* if there is a remaining skb, it gets priority */
664 	if (skb != NULL)
665 		swap(skb, ctx->tx_rem_skb);
666 	else
667 		ready2send = 1;
668 
669 	/*
670 	 * +----------------+
671 	 * | skb_out        |
672 	 * +----------------+
673 	 *           ^ offset
674 	 *        ^ last_offset
675 	 */
676 
677 	/* check if we are resuming an OUT skb */
678 	if (ctx->tx_curr_skb != NULL) {
679 		/* pop variables */
680 		skb_out = ctx->tx_curr_skb;
681 		offset = ctx->tx_curr_offset;
682 		last_offset = ctx->tx_curr_last_offset;
683 		n = ctx->tx_curr_frame_num;
684 
685 	} else {
686 		/* reset variables */
687 		skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
688 		if (skb_out == NULL) {
689 			if (skb != NULL) {
690 				dev_kfree_skb_any(skb);
691 				ctx->netdev->stats.tx_dropped++;
692 			}
693 			goto exit_no_skb;
694 		}
695 
696 		/* make room for NTH and NDP */
697 		offset = ALIGN(sizeof(struct usb_cdc_ncm_nth16),
698 					ctx->tx_ndp_modulus) +
699 					sizeof(struct usb_cdc_ncm_ndp16) +
700 					(ctx->tx_max_datagrams + 1) *
701 					sizeof(struct usb_cdc_ncm_dpe16);
702 
703 		/* store last valid offset before alignment */
704 		last_offset = offset;
705 		/* align first Datagram offset correctly */
706 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
707 		/* zero buffer till the first IP datagram */
708 		cdc_ncm_zero_fill(skb_out->data, 0, offset, offset);
709 		n = 0;
710 		ctx->tx_curr_frame_num = 0;
711 	}
712 
713 	for (; n < ctx->tx_max_datagrams; n++) {
714 		/* check if end of transmit buffer is reached */
715 		if (offset >= ctx->tx_max) {
716 			ready2send = 1;
717 			break;
718 		}
719 		/* compute maximum buffer size */
720 		rem = ctx->tx_max - offset;
721 
722 		if (skb == NULL) {
723 			skb = ctx->tx_rem_skb;
724 			ctx->tx_rem_skb = NULL;
725 
726 			/* check for end of skb */
727 			if (skb == NULL)
728 				break;
729 		}
730 
731 		if (skb->len > rem) {
732 			if (n == 0) {
733 				/* won't fit, MTU problem? */
734 				dev_kfree_skb_any(skb);
735 				skb = NULL;
736 				ctx->netdev->stats.tx_dropped++;
737 			} else {
738 				/* no room for skb - store for later */
739 				if (ctx->tx_rem_skb != NULL) {
740 					dev_kfree_skb_any(ctx->tx_rem_skb);
741 					ctx->netdev->stats.tx_dropped++;
742 				}
743 				ctx->tx_rem_skb = skb;
744 				skb = NULL;
745 				ready2send = 1;
746 			}
747 			break;
748 		}
749 
750 		memcpy(((u8 *)skb_out->data) + offset, skb->data, skb->len);
751 
752 		ctx->tx_ncm.dpe16[n].wDatagramLength = cpu_to_le16(skb->len);
753 		ctx->tx_ncm.dpe16[n].wDatagramIndex = cpu_to_le16(offset);
754 
755 		/* update offset */
756 		offset += skb->len;
757 
758 		/* store last valid offset before alignment */
759 		last_offset = offset;
760 
761 		/* align offset correctly */
762 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
763 
764 		/* zero padding */
765 		cdc_ncm_zero_fill(skb_out->data, last_offset, offset,
766 								ctx->tx_max);
767 		dev_kfree_skb_any(skb);
768 		skb = NULL;
769 	}
770 
771 	/* free up any dangling skb */
772 	if (skb != NULL) {
773 		dev_kfree_skb_any(skb);
774 		skb = NULL;
775 		ctx->netdev->stats.tx_dropped++;
776 	}
777 
778 	ctx->tx_curr_frame_num = n;
779 
780 	if (n == 0) {
781 		/* wait for more frames */
782 		/* push variables */
783 		ctx->tx_curr_skb = skb_out;
784 		ctx->tx_curr_offset = offset;
785 		ctx->tx_curr_last_offset = last_offset;
786 		goto exit_no_skb;
787 
788 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
789 		/* wait for more frames */
790 		/* push variables */
791 		ctx->tx_curr_skb = skb_out;
792 		ctx->tx_curr_offset = offset;
793 		ctx->tx_curr_last_offset = last_offset;
794 		/* set the pending count */
795 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
796 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
797 		goto exit_no_skb;
798 
799 	} else {
800 		/* frame goes out */
801 		/* variables will be reset at next call */
802 	}
803 
804 	/* check for overflow */
805 	if (last_offset > ctx->tx_max)
806 		last_offset = ctx->tx_max;
807 
808 	/* revert offset */
809 	offset = last_offset;
810 
811 	/*
812 	 * If collected data size is less or equal CDC_NCM_MIN_TX_PKT bytes,
813 	 * we send buffers as it is. If we get more data, it would be more
814 	 * efficient for USB HS mobile device with DMA engine to receive a full
815 	 * size NTB, than canceling DMA transfer and receiving a short packet.
816 	 */
817 	if (offset > CDC_NCM_MIN_TX_PKT)
818 		offset = ctx->tx_max;
819 
820 	/* final zero padding */
821 	cdc_ncm_zero_fill(skb_out->data, last_offset, offset, ctx->tx_max);
822 
823 	/* store last offset */
824 	last_offset = offset;
825 
826 	if (((last_offset < ctx->tx_max) && ((last_offset %
827 			le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) ||
828 	    (((last_offset == ctx->tx_max) && ((ctx->tx_max %
829 		le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) &&
830 		(ctx->tx_max < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)))) {
831 		/* force short packet */
832 		*(((u8 *)skb_out->data) + last_offset) = 0;
833 		last_offset++;
834 	}
835 
836 	/* zero the rest of the DPEs plus the last NULL entry */
837 	for (; n <= CDC_NCM_DPT_DATAGRAMS_MAX; n++) {
838 		ctx->tx_ncm.dpe16[n].wDatagramLength = 0;
839 		ctx->tx_ncm.dpe16[n].wDatagramIndex = 0;
840 	}
841 
842 	/* fill out 16-bit NTB header */
843 	ctx->tx_ncm.nth16.dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
844 	ctx->tx_ncm.nth16.wHeaderLength =
845 					cpu_to_le16(sizeof(ctx->tx_ncm.nth16));
846 	ctx->tx_ncm.nth16.wSequence = cpu_to_le16(ctx->tx_seq);
847 	ctx->tx_ncm.nth16.wBlockLength = cpu_to_le16(last_offset);
848 	index = ALIGN(sizeof(struct usb_cdc_ncm_nth16), ctx->tx_ndp_modulus);
849 	ctx->tx_ncm.nth16.wNdpIndex = cpu_to_le16(index);
850 
851 	memcpy(skb_out->data, &(ctx->tx_ncm.nth16), sizeof(ctx->tx_ncm.nth16));
852 	ctx->tx_seq++;
853 
854 	/* fill out 16-bit NDP table */
855 	ctx->tx_ncm.ndp16.dwSignature =
856 				cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN);
857 	rem = sizeof(ctx->tx_ncm.ndp16) + ((ctx->tx_curr_frame_num + 1) *
858 					sizeof(struct usb_cdc_ncm_dpe16));
859 	ctx->tx_ncm.ndp16.wLength = cpu_to_le16(rem);
860 	ctx->tx_ncm.ndp16.wNextNdpIndex = 0; /* reserved */
861 
862 	memcpy(((u8 *)skb_out->data) + index,
863 						&(ctx->tx_ncm.ndp16),
864 						sizeof(ctx->tx_ncm.ndp16));
865 
866 	memcpy(((u8 *)skb_out->data) + index + sizeof(ctx->tx_ncm.ndp16),
867 					&(ctx->tx_ncm.dpe16),
868 					(ctx->tx_curr_frame_num + 1) *
869 					sizeof(struct usb_cdc_ncm_dpe16));
870 
871 	/* set frame length */
872 	skb_put(skb_out, last_offset);
873 
874 	/* return skb */
875 	ctx->tx_curr_skb = NULL;
876 	ctx->netdev->stats.tx_packets += ctx->tx_curr_frame_num;
877 	return skb_out;
878 
879 exit_no_skb:
880 	/* Start timer, if there is a remaining skb */
881 	if (ctx->tx_curr_skb != NULL)
882 		cdc_ncm_tx_timeout_start(ctx);
883 	return NULL;
884 }
885 
886 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
887 {
888 	/* start timer, if not already started */
889 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
890 		hrtimer_start(&ctx->tx_timer,
891 				ktime_set(0, CDC_NCM_TIMER_INTERVAL),
892 				HRTIMER_MODE_REL);
893 }
894 
895 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
896 {
897 	struct cdc_ncm_ctx *ctx =
898 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
899 
900 	if (!atomic_read(&ctx->stop))
901 		tasklet_schedule(&ctx->bh);
902 	return HRTIMER_NORESTART;
903 }
904 
905 static void cdc_ncm_txpath_bh(unsigned long param)
906 {
907 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)param;
908 
909 	spin_lock_bh(&ctx->mtx);
910 	if (ctx->tx_timer_pending != 0) {
911 		ctx->tx_timer_pending--;
912 		cdc_ncm_tx_timeout_start(ctx);
913 		spin_unlock_bh(&ctx->mtx);
914 	} else if (ctx->netdev != NULL) {
915 		spin_unlock_bh(&ctx->mtx);
916 		netif_tx_lock_bh(ctx->netdev);
917 		usbnet_start_xmit(NULL, ctx->netdev);
918 		netif_tx_unlock_bh(ctx->netdev);
919 	}
920 }
921 
922 static struct sk_buff *
923 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
924 {
925 	struct sk_buff *skb_out;
926 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
927 
928 	/*
929 	 * The Ethernet API we are using does not support transmitting
930 	 * multiple Ethernet frames in a single call. This driver will
931 	 * accumulate multiple Ethernet frames and send out a larger
932 	 * USB frame when the USB buffer is full or when a single jiffies
933 	 * timeout happens.
934 	 */
935 	if (ctx == NULL)
936 		goto error;
937 
938 	spin_lock_bh(&ctx->mtx);
939 	skb_out = cdc_ncm_fill_tx_frame(ctx, skb);
940 	spin_unlock_bh(&ctx->mtx);
941 	return skb_out;
942 
943 error:
944 	if (skb != NULL)
945 		dev_kfree_skb_any(skb);
946 
947 	return NULL;
948 }
949 
950 static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
951 {
952 	struct sk_buff *skb;
953 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
954 	int len;
955 	int nframes;
956 	int x;
957 	int offset;
958 	struct usb_cdc_ncm_nth16 *nth16;
959 	struct usb_cdc_ncm_ndp16 *ndp16;
960 	struct usb_cdc_ncm_dpe16 *dpe16;
961 
962 	if (ctx == NULL)
963 		goto error;
964 
965 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
966 					sizeof(struct usb_cdc_ncm_ndp16))) {
967 		pr_debug("frame too short\n");
968 		goto error;
969 	}
970 
971 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
972 
973 	if (le32_to_cpu(nth16->dwSignature) != USB_CDC_NCM_NTH16_SIGN) {
974 		pr_debug("invalid NTH16 signature <%u>\n",
975 					le32_to_cpu(nth16->dwSignature));
976 		goto error;
977 	}
978 
979 	len = le16_to_cpu(nth16->wBlockLength);
980 	if (len > ctx->rx_max) {
981 		pr_debug("unsupported NTB block length %u/%u\n", len,
982 								ctx->rx_max);
983 		goto error;
984 	}
985 
986 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
987 		(ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
988 		!((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
989 		pr_debug("sequence number glitch prev=%d curr=%d\n",
990 				ctx->rx_seq, le16_to_cpu(nth16->wSequence));
991 	}
992 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
993 
994 	len = le16_to_cpu(nth16->wNdpIndex);
995 	if ((len + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
996 		pr_debug("invalid DPT16 index <%u>\n",
997 					le16_to_cpu(nth16->wNdpIndex));
998 		goto error;
999 	}
1000 
1001 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(((u8 *)skb_in->data) + len);
1002 
1003 	if (le32_to_cpu(ndp16->dwSignature) != USB_CDC_NCM_NDP16_NOCRC_SIGN) {
1004 		pr_debug("invalid DPT16 signature <%u>\n",
1005 					le32_to_cpu(ndp16->dwSignature));
1006 		goto error;
1007 	}
1008 
1009 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1010 		pr_debug("invalid DPT16 length <%u>\n",
1011 					le32_to_cpu(ndp16->dwSignature));
1012 		goto error;
1013 	}
1014 
1015 	nframes = ((le16_to_cpu(ndp16->wLength) -
1016 					sizeof(struct usb_cdc_ncm_ndp16)) /
1017 					sizeof(struct usb_cdc_ncm_dpe16));
1018 	nframes--; /* we process NDP entries except for the last one */
1019 
1020 	len += sizeof(struct usb_cdc_ncm_ndp16);
1021 
1022 	if ((len + nframes * (sizeof(struct usb_cdc_ncm_dpe16))) >
1023 								skb_in->len) {
1024 		pr_debug("Invalid nframes = %d\n", nframes);
1025 		goto error;
1026 	}
1027 
1028 	dpe16 = (struct usb_cdc_ncm_dpe16 *)(((u8 *)skb_in->data) + len);
1029 
1030 	for (x = 0; x < nframes; x++, dpe16++) {
1031 		offset = le16_to_cpu(dpe16->wDatagramIndex);
1032 		len = le16_to_cpu(dpe16->wDatagramLength);
1033 
1034 		/*
1035 		 * CDC NCM ch. 3.7
1036 		 * All entries after first NULL entry are to be ignored
1037 		 */
1038 		if ((offset == 0) || (len == 0)) {
1039 			if (!x)
1040 				goto error; /* empty NTB */
1041 			break;
1042 		}
1043 
1044 		/* sanity checking */
1045 		if (((offset + len) > skb_in->len) ||
1046 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1047 			pr_debug("invalid frame detected (ignored)"
1048 					"offset[%u]=%u, length=%u, skb=%p\n",
1049 					x, offset, len, skb_in);
1050 			if (!x)
1051 				goto error;
1052 			break;
1053 
1054 		} else {
1055 			skb = skb_clone(skb_in, GFP_ATOMIC);
1056 			if (!skb)
1057 				goto error;
1058 			skb->len = len;
1059 			skb->data = ((u8 *)skb_in->data) + offset;
1060 			skb_set_tail_pointer(skb, len);
1061 			usbnet_skb_return(dev, skb);
1062 		}
1063 	}
1064 	return 1;
1065 error:
1066 	return 0;
1067 }
1068 
1069 static void
1070 cdc_ncm_speed_change(struct cdc_ncm_ctx *ctx,
1071 		     struct usb_cdc_speed_change *data)
1072 {
1073 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1074 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1075 
1076 	/*
1077 	 * Currently the USB-NET API does not support reporting the actual
1078 	 * device speed. Do print it instead.
1079 	 */
1080 	if ((tx_speed != ctx->tx_speed) || (rx_speed != ctx->rx_speed)) {
1081 		ctx->tx_speed = tx_speed;
1082 		ctx->rx_speed = rx_speed;
1083 
1084 		if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1085 			printk(KERN_INFO KBUILD_MODNAME
1086 				": %s: %u mbit/s downlink "
1087 				"%u mbit/s uplink\n",
1088 				ctx->netdev->name,
1089 				(unsigned int)(rx_speed / 1000000U),
1090 				(unsigned int)(tx_speed / 1000000U));
1091 		} else {
1092 			printk(KERN_INFO KBUILD_MODNAME
1093 				": %s: %u kbit/s downlink "
1094 				"%u kbit/s uplink\n",
1095 				ctx->netdev->name,
1096 				(unsigned int)(rx_speed / 1000U),
1097 				(unsigned int)(tx_speed / 1000U));
1098 		}
1099 	}
1100 }
1101 
1102 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1103 {
1104 	struct cdc_ncm_ctx *ctx;
1105 	struct usb_cdc_notification *event;
1106 
1107 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1108 
1109 	if (urb->actual_length < sizeof(*event))
1110 		return;
1111 
1112 	/* test for split data in 8-byte chunks */
1113 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1114 		cdc_ncm_speed_change(ctx,
1115 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1116 		return;
1117 	}
1118 
1119 	event = urb->transfer_buffer;
1120 
1121 	switch (event->bNotificationType) {
1122 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1123 		/*
1124 		 * According to the CDC NCM specification ch.7.1
1125 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1126 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1127 		 */
1128 		ctx->connected = event->wValue;
1129 
1130 		printk(KERN_INFO KBUILD_MODNAME ": %s: network connection:"
1131 			" %sconnected\n",
1132 			ctx->netdev->name, ctx->connected ? "" : "dis");
1133 
1134 		if (ctx->connected)
1135 			netif_carrier_on(dev->net);
1136 		else {
1137 			netif_carrier_off(dev->net);
1138 			ctx->tx_speed = ctx->rx_speed = 0;
1139 		}
1140 		break;
1141 
1142 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1143 		if (urb->actual_length < (sizeof(*event) +
1144 					sizeof(struct usb_cdc_speed_change)))
1145 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1146 		else
1147 			cdc_ncm_speed_change(ctx,
1148 				(struct usb_cdc_speed_change *) &event[1]);
1149 		break;
1150 
1151 	default:
1152 		dev_err(&dev->udev->dev, "NCM: unexpected "
1153 			"notification 0x%02x!\n", event->bNotificationType);
1154 		break;
1155 	}
1156 }
1157 
1158 static int cdc_ncm_check_connect(struct usbnet *dev)
1159 {
1160 	struct cdc_ncm_ctx *ctx;
1161 
1162 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1163 	if (ctx == NULL)
1164 		return 1;	/* disconnected */
1165 
1166 	return !ctx->connected;
1167 }
1168 
1169 static int
1170 cdc_ncm_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1171 {
1172 	return usbnet_probe(udev, prod);
1173 }
1174 
1175 static void cdc_ncm_disconnect(struct usb_interface *intf)
1176 {
1177 	struct usbnet *dev = usb_get_intfdata(intf);
1178 
1179 	if (dev == NULL)
1180 		return;		/* already disconnected */
1181 
1182 	usbnet_disconnect(intf);
1183 }
1184 
1185 static int cdc_ncm_manage_power(struct usbnet *dev, int status)
1186 {
1187 	dev->intf->needs_remote_wakeup = status;
1188 	return 0;
1189 }
1190 
1191 static const struct driver_info cdc_ncm_info = {
1192 	.description = "CDC NCM",
1193 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET,
1194 	.bind = cdc_ncm_bind,
1195 	.unbind = cdc_ncm_unbind,
1196 	.check_connect = cdc_ncm_check_connect,
1197 	.manage_power = cdc_ncm_manage_power,
1198 	.status = cdc_ncm_status,
1199 	.rx_fixup = cdc_ncm_rx_fixup,
1200 	.tx_fixup = cdc_ncm_tx_fixup,
1201 };
1202 
1203 /* Same as cdc_ncm_info, but with FLAG_WWAN */
1204 static const struct driver_info wwan_info = {
1205 	.description = "Mobile Broadband Network Device",
1206 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET
1207 			| FLAG_WWAN,
1208 	.bind = cdc_ncm_bind,
1209 	.unbind = cdc_ncm_unbind,
1210 	.check_connect = cdc_ncm_check_connect,
1211 	.manage_power = cdc_ncm_manage_power,
1212 	.status = cdc_ncm_status,
1213 	.rx_fixup = cdc_ncm_rx_fixup,
1214 	.tx_fixup = cdc_ncm_tx_fixup,
1215 };
1216 
1217 static const struct usb_device_id cdc_devs[] = {
1218 	/* Ericsson MBM devices like F5521gw */
1219 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1220 		| USB_DEVICE_ID_MATCH_VENDOR,
1221 	  .idVendor = 0x0bdb,
1222 	  .bInterfaceClass = USB_CLASS_COMM,
1223 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1224 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1225 	  .driver_info = (unsigned long) &wwan_info,
1226 	},
1227 
1228 	/* Dell branded MBM devices like DW5550 */
1229 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1230 		| USB_DEVICE_ID_MATCH_VENDOR,
1231 	  .idVendor = 0x413c,
1232 	  .bInterfaceClass = USB_CLASS_COMM,
1233 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1234 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1235 	  .driver_info = (unsigned long) &wwan_info,
1236 	},
1237 
1238 	/* Toshiba branded MBM devices */
1239 	{ .match_flags = USB_DEVICE_ID_MATCH_INT_INFO
1240 		| USB_DEVICE_ID_MATCH_VENDOR,
1241 	  .idVendor = 0x0930,
1242 	  .bInterfaceClass = USB_CLASS_COMM,
1243 	  .bInterfaceSubClass = USB_CDC_SUBCLASS_NCM,
1244 	  .bInterfaceProtocol = USB_CDC_PROTO_NONE,
1245 	  .driver_info = (unsigned long) &wwan_info,
1246 	},
1247 
1248 	/* Generic CDC-NCM devices */
1249 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
1250 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
1251 		.driver_info = (unsigned long)&cdc_ncm_info,
1252 	},
1253 	{
1254 	},
1255 };
1256 MODULE_DEVICE_TABLE(usb, cdc_devs);
1257 
1258 static struct usb_driver cdc_ncm_driver = {
1259 	.name = "cdc_ncm",
1260 	.id_table = cdc_devs,
1261 	.probe = cdc_ncm_probe,
1262 	.disconnect = cdc_ncm_disconnect,
1263 	.suspend = usbnet_suspend,
1264 	.resume = usbnet_resume,
1265 	.reset_resume =	usbnet_resume,
1266 	.supports_autosuspend = 1,
1267 	.disable_hub_initiated_lpm = 1,
1268 };
1269 
1270 module_usb_driver(cdc_ncm_driver);
1271 
1272 MODULE_AUTHOR("Hans Petter Selasky");
1273 MODULE_DESCRIPTION("USB CDC NCM host driver");
1274 MODULE_LICENSE("Dual BSD/GPL");
1275