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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_ncm.c -- USB CDC Network (NCM) link function driver
4  *
5  * Copyright (C) 2010 Nokia Corporation
6  * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
7  *
8  * The driver borrows from f_ecm.c which is:
9  *
10  * Copyright (C) 2003-2005,2008 David Brownell
11  * Copyright (C) 2008 Nokia Corporation
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/interrupt.h>
16 #include <linux/module.h>
17 #include <linux/device.h>
18 #include <linux/etherdevice.h>
19 #include <linux/crc32.h>
20 
21 #include <linux/usb/cdc.h>
22 
23 #include "u_ether.h"
24 #include "u_ether_configfs.h"
25 #include "u_ncm.h"
26 
27 /*
28  * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
29  * NCM is intended to be used with high-speed network attachments.
30  *
31  * Note that NCM requires the use of "alternate settings" for its data
32  * interface.  This means that the set_alt() method has real work to do,
33  * and also means that a get_alt() method is required.
34  */
35 
36 /* to trigger crc/non-crc ndp signature */
37 
38 #define NCM_NDP_HDR_CRC_MASK	0x01000000
39 #define NCM_NDP_HDR_CRC		0x01000000
40 #define NCM_NDP_HDR_NOCRC	0x00000000
41 
42 enum ncm_notify_state {
43 	NCM_NOTIFY_NONE,		/* don't notify */
44 	NCM_NOTIFY_CONNECT,		/* issue CONNECT next */
45 	NCM_NOTIFY_SPEED,		/* issue SPEED_CHANGE next */
46 };
47 
48 struct f_ncm {
49 	struct gether			port;
50 	u8				ctrl_id, data_id;
51 
52 	char				ethaddr[14];
53 
54 	struct usb_ep			*notify;
55 	struct usb_request		*notify_req;
56 	u8				notify_state;
57 	atomic_t			notify_count;
58 	bool				is_open;
59 
60 	const struct ndp_parser_opts	*parser_opts;
61 	bool				is_crc;
62 	u32				ndp_sign;
63 
64 	/*
65 	 * for notification, it is accessed from both
66 	 * callback and ethernet open/close
67 	 */
68 	spinlock_t			lock;
69 
70 	struct net_device		*netdev;
71 
72 	/* For multi-frame NDP TX */
73 	struct sk_buff			*skb_tx_data;
74 	struct sk_buff			*skb_tx_ndp;
75 	u16				ndp_dgram_count;
76 	bool				timer_force_tx;
77 	struct hrtimer			task_timer;
78 	bool				timer_stopping;
79 };
80 
func_to_ncm(struct usb_function * f)81 static inline struct f_ncm *func_to_ncm(struct usb_function *f)
82 {
83 	return container_of(f, struct f_ncm, port.func);
84 }
85 
86 /* peak (theoretical) bulk transfer rate in bits-per-second */
ncm_bitrate(struct usb_gadget * g)87 static inline unsigned ncm_bitrate(struct usb_gadget *g)
88 {
89 	if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
90 		return 4250000000U;
91 	else if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
92 		return 3750000000U;
93 	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
94 		return 13 * 512 * 8 * 1000 * 8;
95 	else
96 		return 19 *  64 * 1 * 1000 * 8;
97 }
98 
99 /*-------------------------------------------------------------------------*/
100 
101 /*
102  * We cannot group frames so use just the minimal size which ok to put
103  * one max-size ethernet frame.
104  * If the host can group frames, allow it to do that, 16K is selected,
105  * because it's used by default by the current linux host driver
106  */
107 #define NTB_DEFAULT_IN_SIZE	16384
108 #define NTB_OUT_SIZE		16384
109 
110 /* Allocation for storing the NDP, 32 should suffice for a
111  * 16k packet. This allows a maximum of 32 * 507 Byte packets to
112  * be transmitted in a single 16kB skb, though when sending full size
113  * packets this limit will be plenty.
114  * Smaller packets are not likely to be trying to maximize the
115  * throughput and will be mstly sending smaller infrequent frames.
116  */
117 #define TX_MAX_NUM_DPE		32
118 
119 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
120 #define TX_TIMEOUT_NSECS	300000
121 
122 #define FORMATS_SUPPORTED	(USB_CDC_NCM_NTB16_SUPPORTED |	\
123 				 USB_CDC_NCM_NTB32_SUPPORTED)
124 
125 static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
126 	.wLength = cpu_to_le16(sizeof(ntb_parameters)),
127 	.bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
128 	.dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
129 	.wNdpInDivisor = cpu_to_le16(4),
130 	.wNdpInPayloadRemainder = cpu_to_le16(0),
131 	.wNdpInAlignment = cpu_to_le16(4),
132 
133 	.dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
134 	.wNdpOutDivisor = cpu_to_le16(4),
135 	.wNdpOutPayloadRemainder = cpu_to_le16(0),
136 	.wNdpOutAlignment = cpu_to_le16(4),
137 };
138 
139 /*
140  * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
141  * packet, to simplify cancellation; and a big transfer interval, to
142  * waste less bandwidth.
143  */
144 
145 #define NCM_STATUS_INTERVAL_MS		32
146 #define NCM_STATUS_BYTECOUNT		16	/* 8 byte header + data */
147 
148 static struct usb_interface_assoc_descriptor ncm_iad_desc = {
149 	.bLength =		sizeof ncm_iad_desc,
150 	.bDescriptorType =	USB_DT_INTERFACE_ASSOCIATION,
151 
152 	/* .bFirstInterface =	DYNAMIC, */
153 	.bInterfaceCount =	2,	/* control + data */
154 	.bFunctionClass =	USB_CLASS_COMM,
155 	.bFunctionSubClass =	USB_CDC_SUBCLASS_NCM,
156 	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
157 	/* .iFunction =		DYNAMIC */
158 };
159 
160 /* interface descriptor: */
161 
162 static struct usb_interface_descriptor ncm_control_intf = {
163 	.bLength =		sizeof ncm_control_intf,
164 	.bDescriptorType =	USB_DT_INTERFACE,
165 
166 	/* .bInterfaceNumber = DYNAMIC */
167 	.bNumEndpoints =	1,
168 	.bInterfaceClass =	USB_CLASS_COMM,
169 	.bInterfaceSubClass =	USB_CDC_SUBCLASS_NCM,
170 	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
171 	/* .iInterface = DYNAMIC */
172 };
173 
174 static struct usb_cdc_header_desc ncm_header_desc = {
175 	.bLength =		sizeof ncm_header_desc,
176 	.bDescriptorType =	USB_DT_CS_INTERFACE,
177 	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
178 
179 	.bcdCDC =		cpu_to_le16(0x0110),
180 };
181 
182 static struct usb_cdc_union_desc ncm_union_desc = {
183 	.bLength =		sizeof(ncm_union_desc),
184 	.bDescriptorType =	USB_DT_CS_INTERFACE,
185 	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
186 	/* .bMasterInterface0 =	DYNAMIC */
187 	/* .bSlaveInterface0 =	DYNAMIC */
188 };
189 
190 static struct usb_cdc_ether_desc ecm_desc = {
191 	.bLength =		sizeof ecm_desc,
192 	.bDescriptorType =	USB_DT_CS_INTERFACE,
193 	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
194 
195 	/* this descriptor actually adds value, surprise! */
196 	/* .iMACAddress = DYNAMIC */
197 	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
198 	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
199 	.wNumberMCFilters =	cpu_to_le16(0),
200 	.bNumberPowerFilters =	0,
201 };
202 
203 #define NCAPS	(USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
204 
205 static struct usb_cdc_ncm_desc ncm_desc = {
206 	.bLength =		sizeof ncm_desc,
207 	.bDescriptorType =	USB_DT_CS_INTERFACE,
208 	.bDescriptorSubType =	USB_CDC_NCM_TYPE,
209 
210 	.bcdNcmVersion =	cpu_to_le16(0x0100),
211 	/* can process SetEthernetPacketFilter */
212 	.bmNetworkCapabilities = NCAPS,
213 };
214 
215 /* the default data interface has no endpoints ... */
216 
217 static struct usb_interface_descriptor ncm_data_nop_intf = {
218 	.bLength =		sizeof ncm_data_nop_intf,
219 	.bDescriptorType =	USB_DT_INTERFACE,
220 
221 	.bInterfaceNumber =	1,
222 	.bAlternateSetting =	0,
223 	.bNumEndpoints =	0,
224 	.bInterfaceClass =	USB_CLASS_CDC_DATA,
225 	.bInterfaceSubClass =	0,
226 	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
227 	/* .iInterface = DYNAMIC */
228 };
229 
230 /* ... but the "real" data interface has two bulk endpoints */
231 
232 static struct usb_interface_descriptor ncm_data_intf = {
233 	.bLength =		sizeof ncm_data_intf,
234 	.bDescriptorType =	USB_DT_INTERFACE,
235 
236 	.bInterfaceNumber =	1,
237 	.bAlternateSetting =	1,
238 	.bNumEndpoints =	2,
239 	.bInterfaceClass =	USB_CLASS_CDC_DATA,
240 	.bInterfaceSubClass =	0,
241 	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
242 	/* .iInterface = DYNAMIC */
243 };
244 
245 /* full speed support: */
246 
247 static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
248 	.bLength =		USB_DT_ENDPOINT_SIZE,
249 	.bDescriptorType =	USB_DT_ENDPOINT,
250 
251 	.bEndpointAddress =	USB_DIR_IN,
252 	.bmAttributes =		USB_ENDPOINT_XFER_INT,
253 	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
254 	.bInterval =		NCM_STATUS_INTERVAL_MS,
255 };
256 
257 static struct usb_endpoint_descriptor fs_ncm_in_desc = {
258 	.bLength =		USB_DT_ENDPOINT_SIZE,
259 	.bDescriptorType =	USB_DT_ENDPOINT,
260 
261 	.bEndpointAddress =	USB_DIR_IN,
262 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
263 };
264 
265 static struct usb_endpoint_descriptor fs_ncm_out_desc = {
266 	.bLength =		USB_DT_ENDPOINT_SIZE,
267 	.bDescriptorType =	USB_DT_ENDPOINT,
268 
269 	.bEndpointAddress =	USB_DIR_OUT,
270 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
271 };
272 
273 static struct usb_descriptor_header *ncm_fs_function[] = {
274 	(struct usb_descriptor_header *) &ncm_iad_desc,
275 	/* CDC NCM control descriptors */
276 	(struct usb_descriptor_header *) &ncm_control_intf,
277 	(struct usb_descriptor_header *) &ncm_header_desc,
278 	(struct usb_descriptor_header *) &ncm_union_desc,
279 	(struct usb_descriptor_header *) &ecm_desc,
280 	(struct usb_descriptor_header *) &ncm_desc,
281 	(struct usb_descriptor_header *) &fs_ncm_notify_desc,
282 	/* data interface, altsettings 0 and 1 */
283 	(struct usb_descriptor_header *) &ncm_data_nop_intf,
284 	(struct usb_descriptor_header *) &ncm_data_intf,
285 	(struct usb_descriptor_header *) &fs_ncm_in_desc,
286 	(struct usb_descriptor_header *) &fs_ncm_out_desc,
287 	NULL,
288 };
289 
290 /* high speed support: */
291 
292 static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
293 	.bLength =		USB_DT_ENDPOINT_SIZE,
294 	.bDescriptorType =	USB_DT_ENDPOINT,
295 
296 	.bEndpointAddress =	USB_DIR_IN,
297 	.bmAttributes =		USB_ENDPOINT_XFER_INT,
298 	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
299 	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
300 };
301 static struct usb_endpoint_descriptor hs_ncm_in_desc = {
302 	.bLength =		USB_DT_ENDPOINT_SIZE,
303 	.bDescriptorType =	USB_DT_ENDPOINT,
304 
305 	.bEndpointAddress =	USB_DIR_IN,
306 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
307 	.wMaxPacketSize =	cpu_to_le16(512),
308 };
309 
310 static struct usb_endpoint_descriptor hs_ncm_out_desc = {
311 	.bLength =		USB_DT_ENDPOINT_SIZE,
312 	.bDescriptorType =	USB_DT_ENDPOINT,
313 
314 	.bEndpointAddress =	USB_DIR_OUT,
315 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
316 	.wMaxPacketSize =	cpu_to_le16(512),
317 };
318 
319 static struct usb_descriptor_header *ncm_hs_function[] = {
320 	(struct usb_descriptor_header *) &ncm_iad_desc,
321 	/* CDC NCM control descriptors */
322 	(struct usb_descriptor_header *) &ncm_control_intf,
323 	(struct usb_descriptor_header *) &ncm_header_desc,
324 	(struct usb_descriptor_header *) &ncm_union_desc,
325 	(struct usb_descriptor_header *) &ecm_desc,
326 	(struct usb_descriptor_header *) &ncm_desc,
327 	(struct usb_descriptor_header *) &hs_ncm_notify_desc,
328 	/* data interface, altsettings 0 and 1 */
329 	(struct usb_descriptor_header *) &ncm_data_nop_intf,
330 	(struct usb_descriptor_header *) &ncm_data_intf,
331 	(struct usb_descriptor_header *) &hs_ncm_in_desc,
332 	(struct usb_descriptor_header *) &hs_ncm_out_desc,
333 	NULL,
334 };
335 
336 
337 /* super speed support: */
338 
339 static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
340 	.bLength =		USB_DT_ENDPOINT_SIZE,
341 	.bDescriptorType =	USB_DT_ENDPOINT,
342 
343 	.bEndpointAddress =	USB_DIR_IN,
344 	.bmAttributes =		USB_ENDPOINT_XFER_INT,
345 	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
346 	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
347 };
348 
349 static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
350 	.bLength =		sizeof(ss_ncm_notify_comp_desc),
351 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
352 
353 	/* the following 3 values can be tweaked if necessary */
354 	/* .bMaxBurst =		0, */
355 	/* .bmAttributes =	0, */
356 	.wBytesPerInterval =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
357 };
358 
359 static struct usb_endpoint_descriptor ss_ncm_in_desc = {
360 	.bLength =		USB_DT_ENDPOINT_SIZE,
361 	.bDescriptorType =	USB_DT_ENDPOINT,
362 
363 	.bEndpointAddress =	USB_DIR_IN,
364 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
365 	.wMaxPacketSize =	cpu_to_le16(1024),
366 };
367 
368 static struct usb_endpoint_descriptor ss_ncm_out_desc = {
369 	.bLength =		USB_DT_ENDPOINT_SIZE,
370 	.bDescriptorType =	USB_DT_ENDPOINT,
371 
372 	.bEndpointAddress =	USB_DIR_OUT,
373 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
374 	.wMaxPacketSize =	cpu_to_le16(1024),
375 };
376 
377 static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
378 	.bLength =		sizeof(ss_ncm_bulk_comp_desc),
379 	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
380 
381 	/* the following 2 values can be tweaked if necessary */
382 	/* .bMaxBurst =		0, */
383 	/* .bmAttributes =	0, */
384 };
385 
386 static struct usb_descriptor_header *ncm_ss_function[] = {
387 	(struct usb_descriptor_header *) &ncm_iad_desc,
388 	/* CDC NCM control descriptors */
389 	(struct usb_descriptor_header *) &ncm_control_intf,
390 	(struct usb_descriptor_header *) &ncm_header_desc,
391 	(struct usb_descriptor_header *) &ncm_union_desc,
392 	(struct usb_descriptor_header *) &ecm_desc,
393 	(struct usb_descriptor_header *) &ncm_desc,
394 	(struct usb_descriptor_header *) &ss_ncm_notify_desc,
395 	(struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
396 	/* data interface, altsettings 0 and 1 */
397 	(struct usb_descriptor_header *) &ncm_data_nop_intf,
398 	(struct usb_descriptor_header *) &ncm_data_intf,
399 	(struct usb_descriptor_header *) &ss_ncm_in_desc,
400 	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
401 	(struct usb_descriptor_header *) &ss_ncm_out_desc,
402 	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
403 	NULL,
404 };
405 
406 /* string descriptors: */
407 
408 #define STRING_CTRL_IDX	0
409 #define STRING_MAC_IDX	1
410 #define STRING_DATA_IDX	2
411 #define STRING_IAD_IDX	3
412 
413 static struct usb_string ncm_string_defs[] = {
414 	[STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
415 	[STRING_MAC_IDX].s = "",
416 	[STRING_DATA_IDX].s = "CDC Network Data",
417 	[STRING_IAD_IDX].s = "CDC NCM",
418 	{  } /* end of list */
419 };
420 
421 static struct usb_gadget_strings ncm_string_table = {
422 	.language =		0x0409,	/* en-us */
423 	.strings =		ncm_string_defs,
424 };
425 
426 static struct usb_gadget_strings *ncm_strings[] = {
427 	&ncm_string_table,
428 	NULL,
429 };
430 
431 /*
432  * Here are options for NCM Datagram Pointer table (NDP) parser.
433  * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
434  * in NDP16 offsets and sizes fields are 1 16bit word wide,
435  * in NDP32 -- 2 16bit words wide. Also signatures are different.
436  * To make the parser code the same, put the differences in the structure,
437  * and switch pointers to the structures when the format is changed.
438  */
439 
440 struct ndp_parser_opts {
441 	u32		nth_sign;
442 	u32		ndp_sign;
443 	unsigned	nth_size;
444 	unsigned	ndp_size;
445 	unsigned	dpe_size;
446 	unsigned	ndplen_align;
447 	/* sizes in u16 units */
448 	unsigned	dgram_item_len; /* index or length */
449 	unsigned	block_length;
450 	unsigned	ndp_index;
451 	unsigned	reserved1;
452 	unsigned	reserved2;
453 	unsigned	next_ndp_index;
454 };
455 
456 #define INIT_NDP16_OPTS {					\
457 		.nth_sign = USB_CDC_NCM_NTH16_SIGN,		\
458 		.ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,	\
459 		.nth_size = sizeof(struct usb_cdc_ncm_nth16),	\
460 		.ndp_size = sizeof(struct usb_cdc_ncm_ndp16),	\
461 		.dpe_size = sizeof(struct usb_cdc_ncm_dpe16),	\
462 		.ndplen_align = 4,				\
463 		.dgram_item_len = 1,				\
464 		.block_length = 1,				\
465 		.ndp_index = 1,					\
466 		.reserved1 = 0,					\
467 		.reserved2 = 0,					\
468 		.next_ndp_index = 1,				\
469 	}
470 
471 
472 #define INIT_NDP32_OPTS {					\
473 		.nth_sign = USB_CDC_NCM_NTH32_SIGN,		\
474 		.ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,	\
475 		.nth_size = sizeof(struct usb_cdc_ncm_nth32),	\
476 		.ndp_size = sizeof(struct usb_cdc_ncm_ndp32),	\
477 		.dpe_size = sizeof(struct usb_cdc_ncm_dpe32),	\
478 		.ndplen_align = 8,				\
479 		.dgram_item_len = 2,				\
480 		.block_length = 2,				\
481 		.ndp_index = 2,					\
482 		.reserved1 = 1,					\
483 		.reserved2 = 2,					\
484 		.next_ndp_index = 2,				\
485 	}
486 
487 static const struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
488 static const struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
489 
put_ncm(__le16 ** p,unsigned size,unsigned val)490 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
491 {
492 	switch (size) {
493 	case 1:
494 		put_unaligned_le16((u16)val, *p);
495 		break;
496 	case 2:
497 		put_unaligned_le32((u32)val, *p);
498 
499 		break;
500 	default:
501 		BUG();
502 	}
503 
504 	*p += size;
505 }
506 
get_ncm(__le16 ** p,unsigned size)507 static inline unsigned get_ncm(__le16 **p, unsigned size)
508 {
509 	unsigned tmp;
510 
511 	switch (size) {
512 	case 1:
513 		tmp = get_unaligned_le16(*p);
514 		break;
515 	case 2:
516 		tmp = get_unaligned_le32(*p);
517 		break;
518 	default:
519 		BUG();
520 	}
521 
522 	*p += size;
523 	return tmp;
524 }
525 
526 /*-------------------------------------------------------------------------*/
527 
ncm_reset_values(struct f_ncm * ncm)528 static inline void ncm_reset_values(struct f_ncm *ncm)
529 {
530 	ncm->parser_opts = &ndp16_opts;
531 	ncm->is_crc = false;
532 	ncm->port.cdc_filter = DEFAULT_FILTER;
533 
534 	/* doesn't make sense for ncm, fixed size used */
535 	ncm->port.header_len = 0;
536 
537 	ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
538 	ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
539 }
540 
541 /*
542  * Context: ncm->lock held
543  */
ncm_do_notify(struct f_ncm * ncm)544 static void ncm_do_notify(struct f_ncm *ncm)
545 {
546 	struct usb_request		*req = ncm->notify_req;
547 	struct usb_cdc_notification	*event;
548 	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
549 	__le32				*data;
550 	int				status;
551 
552 	/* notification already in flight? */
553 	if (atomic_read(&ncm->notify_count))
554 		return;
555 
556 	event = req->buf;
557 	switch (ncm->notify_state) {
558 	case NCM_NOTIFY_NONE:
559 		return;
560 
561 	case NCM_NOTIFY_CONNECT:
562 		event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
563 		if (ncm->is_open)
564 			event->wValue = cpu_to_le16(1);
565 		else
566 			event->wValue = cpu_to_le16(0);
567 		event->wLength = 0;
568 		req->length = sizeof *event;
569 
570 		DBG(cdev, "notify connect %s\n",
571 				ncm->is_open ? "true" : "false");
572 		ncm->notify_state = NCM_NOTIFY_NONE;
573 		break;
574 
575 	case NCM_NOTIFY_SPEED:
576 		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
577 		event->wValue = cpu_to_le16(0);
578 		event->wLength = cpu_to_le16(8);
579 		req->length = NCM_STATUS_BYTECOUNT;
580 
581 		/* SPEED_CHANGE data is up/down speeds in bits/sec */
582 		data = req->buf + sizeof *event;
583 		data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
584 		data[1] = data[0];
585 
586 		DBG(cdev, "notify speed %d\n", ncm_bitrate(cdev->gadget));
587 		ncm->notify_state = NCM_NOTIFY_CONNECT;
588 		break;
589 	}
590 	event->bmRequestType = 0xA1;
591 	event->wIndex = cpu_to_le16(ncm->ctrl_id);
592 
593 	atomic_inc(&ncm->notify_count);
594 
595 	/*
596 	 * In double buffering if there is a space in FIFO,
597 	 * completion callback can be called right after the call,
598 	 * so unlocking
599 	 */
600 	spin_unlock(&ncm->lock);
601 	status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
602 	spin_lock(&ncm->lock);
603 	if (status < 0) {
604 		atomic_dec(&ncm->notify_count);
605 		DBG(cdev, "notify --> %d\n", status);
606 	}
607 }
608 
609 /*
610  * Context: ncm->lock held
611  */
ncm_notify(struct f_ncm * ncm)612 static void ncm_notify(struct f_ncm *ncm)
613 {
614 	/*
615 	 * NOTE on most versions of Linux, host side cdc-ethernet
616 	 * won't listen for notifications until its netdevice opens.
617 	 * The first notification then sits in the FIFO for a long
618 	 * time, and the second one is queued.
619 	 *
620 	 * If ncm_notify() is called before the second (CONNECT)
621 	 * notification is sent, then it will reset to send the SPEED
622 	 * notificaion again (and again, and again), but it's not a problem
623 	 */
624 	ncm->notify_state = NCM_NOTIFY_SPEED;
625 	ncm_do_notify(ncm);
626 }
627 
ncm_notify_complete(struct usb_ep * ep,struct usb_request * req)628 static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
629 {
630 	struct f_ncm			*ncm = req->context;
631 	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
632 	struct usb_cdc_notification	*event = req->buf;
633 
634 	spin_lock(&ncm->lock);
635 	switch (req->status) {
636 	case 0:
637 		VDBG(cdev, "Notification %02x sent\n",
638 		     event->bNotificationType);
639 		atomic_dec(&ncm->notify_count);
640 		break;
641 	case -ECONNRESET:
642 	case -ESHUTDOWN:
643 		atomic_set(&ncm->notify_count, 0);
644 		ncm->notify_state = NCM_NOTIFY_NONE;
645 		break;
646 	default:
647 		DBG(cdev, "event %02x --> %d\n",
648 			event->bNotificationType, req->status);
649 		atomic_dec(&ncm->notify_count);
650 		break;
651 	}
652 	ncm_do_notify(ncm);
653 	spin_unlock(&ncm->lock);
654 }
655 
ncm_ep0out_complete(struct usb_ep * ep,struct usb_request * req)656 static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
657 {
658 	/* now for SET_NTB_INPUT_SIZE only */
659 	unsigned		in_size;
660 	struct usb_function	*f = req->context;
661 	struct f_ncm		*ncm = func_to_ncm(f);
662 	struct usb_composite_dev *cdev = f->config->cdev;
663 
664 	req->context = NULL;
665 	if (req->status || req->actual != req->length) {
666 		DBG(cdev, "Bad control-OUT transfer\n");
667 		goto invalid;
668 	}
669 
670 	in_size = get_unaligned_le32(req->buf);
671 	if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
672 	    in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
673 		DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
674 		goto invalid;
675 	}
676 
677 	ncm->port.fixed_in_len = in_size;
678 	VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
679 	return;
680 
681 invalid:
682 	usb_ep_set_halt(ep);
683 	return;
684 }
685 
ncm_setup(struct usb_function * f,const struct usb_ctrlrequest * ctrl)686 static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
687 {
688 	struct f_ncm		*ncm = func_to_ncm(f);
689 	struct usb_composite_dev *cdev = f->config->cdev;
690 	struct usb_request	*req = cdev->req;
691 	int			value = -EOPNOTSUPP;
692 	u16			w_index = le16_to_cpu(ctrl->wIndex);
693 	u16			w_value = le16_to_cpu(ctrl->wValue);
694 	u16			w_length = le16_to_cpu(ctrl->wLength);
695 
696 	/*
697 	 * composite driver infrastructure handles everything except
698 	 * CDC class messages; interface activation uses set_alt().
699 	 */
700 	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
701 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
702 			| USB_CDC_SET_ETHERNET_PACKET_FILTER:
703 		/*
704 		 * see 6.2.30: no data, wIndex = interface,
705 		 * wValue = packet filter bitmap
706 		 */
707 		if (w_length != 0 || w_index != ncm->ctrl_id)
708 			goto invalid;
709 		DBG(cdev, "packet filter %02x\n", w_value);
710 		/*
711 		 * REVISIT locking of cdc_filter.  This assumes the UDC
712 		 * driver won't have a concurrent packet TX irq running on
713 		 * another CPU; or that if it does, this write is atomic...
714 		 */
715 		ncm->port.cdc_filter = w_value;
716 		value = 0;
717 		break;
718 	/*
719 	 * and optionally:
720 	 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
721 	 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
722 	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
723 	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
724 	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
725 	 * case USB_CDC_GET_ETHERNET_STATISTIC:
726 	 */
727 
728 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
729 		| USB_CDC_GET_NTB_PARAMETERS:
730 
731 		if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
732 			goto invalid;
733 		value = w_length > sizeof ntb_parameters ?
734 			sizeof ntb_parameters : w_length;
735 		memcpy(req->buf, &ntb_parameters, value);
736 		VDBG(cdev, "Host asked NTB parameters\n");
737 		break;
738 
739 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
740 		| USB_CDC_GET_NTB_INPUT_SIZE:
741 
742 		if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
743 			goto invalid;
744 		put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
745 		value = 4;
746 		VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
747 		     ncm->port.fixed_in_len);
748 		break;
749 
750 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
751 		| USB_CDC_SET_NTB_INPUT_SIZE:
752 	{
753 		if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
754 			goto invalid;
755 		req->complete = ncm_ep0out_complete;
756 		req->length = w_length;
757 		req->context = f;
758 
759 		value = req->length;
760 		break;
761 	}
762 
763 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
764 		| USB_CDC_GET_NTB_FORMAT:
765 	{
766 		uint16_t format;
767 
768 		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
769 			goto invalid;
770 		format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
771 		put_unaligned_le16(format, req->buf);
772 		value = 2;
773 		VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
774 		break;
775 	}
776 
777 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
778 		| USB_CDC_SET_NTB_FORMAT:
779 	{
780 		if (w_length != 0 || w_index != ncm->ctrl_id)
781 			goto invalid;
782 		switch (w_value) {
783 		case 0x0000:
784 			ncm->parser_opts = &ndp16_opts;
785 			DBG(cdev, "NCM16 selected\n");
786 			break;
787 		case 0x0001:
788 			ncm->parser_opts = &ndp32_opts;
789 			DBG(cdev, "NCM32 selected\n");
790 			break;
791 		default:
792 			goto invalid;
793 		}
794 		value = 0;
795 		break;
796 	}
797 	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
798 		| USB_CDC_GET_CRC_MODE:
799 	{
800 		uint16_t is_crc;
801 
802 		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
803 			goto invalid;
804 		is_crc = ncm->is_crc ? 0x0001 : 0x0000;
805 		put_unaligned_le16(is_crc, req->buf);
806 		value = 2;
807 		VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
808 		break;
809 	}
810 
811 	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
812 		| USB_CDC_SET_CRC_MODE:
813 	{
814 		int ndp_hdr_crc = 0;
815 
816 		if (w_length != 0 || w_index != ncm->ctrl_id)
817 			goto invalid;
818 		switch (w_value) {
819 		case 0x0000:
820 			ncm->is_crc = false;
821 			ndp_hdr_crc = NCM_NDP_HDR_NOCRC;
822 			DBG(cdev, "non-CRC mode selected\n");
823 			break;
824 		case 0x0001:
825 			ncm->is_crc = true;
826 			ndp_hdr_crc = NCM_NDP_HDR_CRC;
827 			DBG(cdev, "CRC mode selected\n");
828 			break;
829 		default:
830 			goto invalid;
831 		}
832 		ncm->ndp_sign = ncm->parser_opts->ndp_sign | ndp_hdr_crc;
833 		value = 0;
834 		break;
835 	}
836 
837 	/* and disabled in ncm descriptor: */
838 	/* case USB_CDC_GET_NET_ADDRESS: */
839 	/* case USB_CDC_SET_NET_ADDRESS: */
840 	/* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
841 	/* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
842 
843 	default:
844 invalid:
845 		DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
846 			ctrl->bRequestType, ctrl->bRequest,
847 			w_value, w_index, w_length);
848 	}
849 
850 	/* respond with data transfer or status phase? */
851 	if (value >= 0) {
852 		DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
853 			ctrl->bRequestType, ctrl->bRequest,
854 			w_value, w_index, w_length);
855 		req->zero = 0;
856 		req->length = value;
857 		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
858 		if (value < 0)
859 			ERROR(cdev, "ncm req %02x.%02x response err %d\n",
860 					ctrl->bRequestType, ctrl->bRequest,
861 					value);
862 	}
863 
864 	/* device either stalls (value < 0) or reports success */
865 	return value;
866 }
867 
868 
ncm_set_alt(struct usb_function * f,unsigned intf,unsigned alt)869 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
870 {
871 	struct f_ncm		*ncm = func_to_ncm(f);
872 	struct usb_composite_dev *cdev = f->config->cdev;
873 
874 	/* Control interface has only altsetting 0 */
875 	if (intf == ncm->ctrl_id) {
876 		if (alt != 0)
877 			goto fail;
878 
879 		DBG(cdev, "reset ncm control %d\n", intf);
880 		usb_ep_disable(ncm->notify);
881 
882 		if (!(ncm->notify->desc)) {
883 			DBG(cdev, "init ncm ctrl %d\n", intf);
884 			if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
885 				goto fail;
886 		}
887 		usb_ep_enable(ncm->notify);
888 
889 	/* Data interface has two altsettings, 0 and 1 */
890 	} else if (intf == ncm->data_id) {
891 		if (alt > 1)
892 			goto fail;
893 
894 		if (ncm->port.in_ep->enabled) {
895 			DBG(cdev, "reset ncm\n");
896 			ncm->timer_stopping = true;
897 			ncm->netdev = NULL;
898 			gether_disconnect(&ncm->port);
899 			ncm_reset_values(ncm);
900 		}
901 
902 		/*
903 		 * CDC Network only sends data in non-default altsettings.
904 		 * Changing altsettings resets filters, statistics, etc.
905 		 */
906 		if (alt == 1) {
907 			struct net_device	*net;
908 
909 			if (!ncm->port.in_ep->desc ||
910 			    !ncm->port.out_ep->desc) {
911 				DBG(cdev, "init ncm\n");
912 				if (config_ep_by_speed(cdev->gadget, f,
913 						       ncm->port.in_ep) ||
914 				    config_ep_by_speed(cdev->gadget, f,
915 						       ncm->port.out_ep)) {
916 					ncm->port.in_ep->desc = NULL;
917 					ncm->port.out_ep->desc = NULL;
918 					goto fail;
919 				}
920 			}
921 
922 			/* TODO */
923 			/* Enable zlps by default for NCM conformance;
924 			 * override for musb_hdrc (avoids txdma ovhead)
925 			 */
926 			ncm->port.is_zlp_ok =
927 				gadget_is_zlp_supported(cdev->gadget);
928 			ncm->port.cdc_filter = DEFAULT_FILTER;
929 			DBG(cdev, "activate ncm\n");
930 			net = gether_connect(&ncm->port);
931 			if (IS_ERR(net))
932 				return PTR_ERR(net);
933 			ncm->netdev = net;
934 			ncm->timer_stopping = false;
935 		}
936 
937 		spin_lock(&ncm->lock);
938 		ncm_notify(ncm);
939 		spin_unlock(&ncm->lock);
940 	} else
941 		goto fail;
942 
943 	return 0;
944 fail:
945 	return -EINVAL;
946 }
947 
948 /*
949  * Because the data interface supports multiple altsettings,
950  * this NCM function *MUST* implement a get_alt() method.
951  */
ncm_get_alt(struct usb_function * f,unsigned intf)952 static int ncm_get_alt(struct usb_function *f, unsigned intf)
953 {
954 	struct f_ncm		*ncm = func_to_ncm(f);
955 
956 	if (intf == ncm->ctrl_id)
957 		return 0;
958 	return ncm->port.in_ep->enabled ? 1 : 0;
959 }
960 
package_for_tx(struct f_ncm * ncm)961 static struct sk_buff *package_for_tx(struct f_ncm *ncm)
962 {
963 	__le16		*ntb_iter;
964 	struct sk_buff	*skb2 = NULL;
965 	unsigned	ndp_pad;
966 	unsigned	ndp_index;
967 	unsigned	new_len;
968 
969 	const struct ndp_parser_opts *opts = ncm->parser_opts;
970 	const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
971 	const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
972 
973 	/* Stop the timer */
974 	hrtimer_try_to_cancel(&ncm->task_timer);
975 
976 	ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
977 			ncm->skb_tx_data->len;
978 	ndp_index = ncm->skb_tx_data->len + ndp_pad;
979 	new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
980 
981 	/* Set the final BlockLength and wNdpIndex */
982 	ntb_iter = (void *) ncm->skb_tx_data->data;
983 	/* Increment pointer to BlockLength */
984 	ntb_iter += 2 + 1 + 1;
985 	put_ncm(&ntb_iter, opts->block_length, new_len);
986 	put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
987 
988 	/* Set the final NDP wLength */
989 	new_len = opts->ndp_size +
990 			(ncm->ndp_dgram_count * dgram_idx_len);
991 	ncm->ndp_dgram_count = 0;
992 	/* Increment from start to wLength */
993 	ntb_iter = (void *) ncm->skb_tx_ndp->data;
994 	ntb_iter += 2;
995 	put_unaligned_le16(new_len, ntb_iter);
996 
997 	/* Merge the skbs */
998 	swap(skb2, ncm->skb_tx_data);
999 	if (ncm->skb_tx_data) {
1000 		dev_consume_skb_any(ncm->skb_tx_data);
1001 		ncm->skb_tx_data = NULL;
1002 	}
1003 
1004 	/* Insert NDP alignment. */
1005 	skb_put_zero(skb2, ndp_pad);
1006 
1007 	/* Copy NTB across. */
1008 	skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
1009 	dev_consume_skb_any(ncm->skb_tx_ndp);
1010 	ncm->skb_tx_ndp = NULL;
1011 
1012 	/* Insert zero'd datagram. */
1013 	skb_put_zero(skb2, dgram_idx_len);
1014 
1015 	return skb2;
1016 }
1017 
ncm_wrap_ntb(struct gether * port,struct sk_buff * skb)1018 static struct sk_buff *ncm_wrap_ntb(struct gether *port,
1019 				    struct sk_buff *skb)
1020 {
1021 	struct f_ncm	*ncm = func_to_ncm(&port->func);
1022 	struct sk_buff	*skb2 = NULL;
1023 	int		ncb_len = 0;
1024 	__le16		*ntb_data;
1025 	__le16		*ntb_ndp;
1026 	int		dgram_pad;
1027 
1028 	unsigned	max_size = ncm->port.fixed_in_len;
1029 	const struct ndp_parser_opts *opts = ncm->parser_opts;
1030 	const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1031 	const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1032 	const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1033 	const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1034 
1035 	if (!skb && !ncm->skb_tx_data)
1036 		return NULL;
1037 
1038 	if (skb) {
1039 		/* Add the CRC if required up front */
1040 		if (ncm->is_crc) {
1041 			uint32_t	crc;
1042 			__le16		*crc_pos;
1043 
1044 			crc = ~crc32_le(~0,
1045 					skb->data,
1046 					skb->len);
1047 			crc_pos = skb_put(skb, sizeof(uint32_t));
1048 			put_unaligned_le32(crc, crc_pos);
1049 		}
1050 
1051 		/* If the new skb is too big for the current NCM NTB then
1052 		 * set the current stored skb to be sent now and clear it
1053 		 * ready for new data.
1054 		 * NOTE: Assume maximum align for speed of calculation.
1055 		 */
1056 		if (ncm->skb_tx_data
1057 		    && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1058 		    || (ncm->skb_tx_data->len +
1059 		    div + rem + skb->len +
1060 		    ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1061 		    > max_size)) {
1062 			skb2 = package_for_tx(ncm);
1063 			if (!skb2)
1064 				goto err;
1065 		}
1066 
1067 		if (!ncm->skb_tx_data) {
1068 			ncb_len = opts->nth_size;
1069 			dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1070 			ncb_len += dgram_pad;
1071 
1072 			/* Create a new skb for the NTH and datagrams. */
1073 			ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1074 			if (!ncm->skb_tx_data)
1075 				goto err;
1076 
1077 			ncm->skb_tx_data->dev = ncm->netdev;
1078 			ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1079 			/* dwSignature */
1080 			put_unaligned_le32(opts->nth_sign, ntb_data);
1081 			ntb_data += 2;
1082 			/* wHeaderLength */
1083 			put_unaligned_le16(opts->nth_size, ntb_data++);
1084 
1085 			/* Allocate an skb for storing the NDP,
1086 			 * TX_MAX_NUM_DPE should easily suffice for a
1087 			 * 16k packet.
1088 			 */
1089 			ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1090 						    + opts->dpe_size
1091 						    * TX_MAX_NUM_DPE),
1092 						    GFP_ATOMIC);
1093 			if (!ncm->skb_tx_ndp)
1094 				goto err;
1095 
1096 			ncm->skb_tx_ndp->dev = ncm->netdev;
1097 			ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1098 			memset(ntb_ndp, 0, ncb_len);
1099 			/* dwSignature */
1100 			put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1101 			ntb_ndp += 2;
1102 
1103 			/* There is always a zeroed entry */
1104 			ncm->ndp_dgram_count = 1;
1105 
1106 			/* Note: we skip opts->next_ndp_index */
1107 		}
1108 
1109 		/* Delay the timer. */
1110 		hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1111 			      HRTIMER_MODE_REL_SOFT);
1112 
1113 		/* Add the datagram position entries */
1114 		ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1115 
1116 		ncb_len = ncm->skb_tx_data->len;
1117 		dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1118 		ncb_len += dgram_pad;
1119 
1120 		/* (d)wDatagramIndex */
1121 		put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1122 		/* (d)wDatagramLength */
1123 		put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1124 		ncm->ndp_dgram_count++;
1125 
1126 		/* Add the new data to the skb */
1127 		skb_put_zero(ncm->skb_tx_data, dgram_pad);
1128 		skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1129 		dev_consume_skb_any(skb);
1130 		skb = NULL;
1131 
1132 	} else if (ncm->skb_tx_data && ncm->timer_force_tx) {
1133 		/* If the tx was requested because of a timeout then send */
1134 		skb2 = package_for_tx(ncm);
1135 		if (!skb2)
1136 			goto err;
1137 	}
1138 
1139 	return skb2;
1140 
1141 err:
1142 	ncm->netdev->stats.tx_dropped++;
1143 
1144 	if (skb)
1145 		dev_kfree_skb_any(skb);
1146 	if (ncm->skb_tx_data)
1147 		dev_kfree_skb_any(ncm->skb_tx_data);
1148 	if (ncm->skb_tx_ndp)
1149 		dev_kfree_skb_any(ncm->skb_tx_ndp);
1150 
1151 	return NULL;
1152 }
1153 
1154 /*
1155  * The transmit should only be run if no skb data has been sent
1156  * for a certain duration.
1157  */
ncm_tx_timeout(struct hrtimer * data)1158 static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1159 {
1160 	struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1161 
1162 	/* Only send if data is available. */
1163 	if (!ncm->timer_stopping && ncm->skb_tx_data) {
1164 		ncm->timer_force_tx = true;
1165 
1166 		/* XXX This allowance of a NULL skb argument to ndo_start_xmit
1167 		 * XXX is not sane.  The gadget layer should be redesigned so
1168 		 * XXX that the dev->wrap() invocations to build SKBs is transparent
1169 		 * XXX and performed in some way outside of the ndo_start_xmit
1170 		 * XXX interface.
1171 		 */
1172 		ncm->netdev->netdev_ops->ndo_start_xmit(NULL, ncm->netdev);
1173 
1174 		ncm->timer_force_tx = false;
1175 	}
1176 	return HRTIMER_NORESTART;
1177 }
1178 
ncm_unwrap_ntb(struct gether * port,struct sk_buff * skb,struct sk_buff_head * list)1179 static int ncm_unwrap_ntb(struct gether *port,
1180 			  struct sk_buff *skb,
1181 			  struct sk_buff_head *list)
1182 {
1183 	struct f_ncm	*ncm = func_to_ncm(&port->func);
1184 	__le16		*tmp = (void *) skb->data;
1185 	unsigned	index, index2;
1186 	int		ndp_index;
1187 	unsigned	dg_len, dg_len2;
1188 	unsigned	ndp_len;
1189 	unsigned	block_len;
1190 	struct sk_buff	*skb2;
1191 	int		ret = -EINVAL;
1192 	unsigned	ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1193 	unsigned	frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
1194 	const struct ndp_parser_opts *opts = ncm->parser_opts;
1195 	unsigned	crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1196 	int		dgram_counter;
1197 
1198 	/* dwSignature */
1199 	if (get_unaligned_le32(tmp) != opts->nth_sign) {
1200 		INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1201 			skb->len);
1202 		print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1203 			       skb->data, 32, false);
1204 
1205 		goto err;
1206 	}
1207 	tmp += 2;
1208 	/* wHeaderLength */
1209 	if (get_unaligned_le16(tmp++) != opts->nth_size) {
1210 		INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1211 		goto err;
1212 	}
1213 	tmp++; /* skip wSequence */
1214 
1215 	block_len = get_ncm(&tmp, opts->block_length);
1216 	/* (d)wBlockLength */
1217 	if (block_len > ntb_max) {
1218 		INFO(port->func.config->cdev, "OUT size exceeded\n");
1219 		goto err;
1220 	}
1221 
1222 	ndp_index = get_ncm(&tmp, opts->ndp_index);
1223 
1224 	/* Run through all the NDP's in the NTB */
1225 	do {
1226 		/*
1227 		 * NCM 3.2
1228 		 * dwNdpIndex
1229 		 */
1230 		if (((ndp_index % 4) != 0) ||
1231 				(ndp_index < opts->nth_size) ||
1232 				(ndp_index > (block_len -
1233 					      opts->ndp_size))) {
1234 			INFO(port->func.config->cdev, "Bad index: %#X\n",
1235 			     ndp_index);
1236 			goto err;
1237 		}
1238 
1239 		/*
1240 		 * walk through NDP
1241 		 * dwSignature
1242 		 */
1243 		tmp = (void *)(skb->data + ndp_index);
1244 		if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1245 			INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1246 			goto err;
1247 		}
1248 		tmp += 2;
1249 
1250 		ndp_len = get_unaligned_le16(tmp++);
1251 		/*
1252 		 * NCM 3.3.1
1253 		 * wLength
1254 		 * entry is 2 items
1255 		 * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1256 		 * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1257 		 * Each entry is a dgram index and a dgram length.
1258 		 */
1259 		if ((ndp_len < opts->ndp_size
1260 				+ 2 * 2 * (opts->dgram_item_len * 2)) ||
1261 				(ndp_len % opts->ndplen_align != 0)) {
1262 			INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1263 			     ndp_len);
1264 			goto err;
1265 		}
1266 		tmp += opts->reserved1;
1267 		/* Check for another NDP (d)wNextNdpIndex */
1268 		ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1269 		tmp += opts->reserved2;
1270 
1271 		ndp_len -= opts->ndp_size;
1272 		index2 = get_ncm(&tmp, opts->dgram_item_len);
1273 		dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1274 		dgram_counter = 0;
1275 
1276 		do {
1277 			index = index2;
1278 			/* wDatagramIndex[0] */
1279 			if ((index < opts->nth_size) ||
1280 					(index > block_len - opts->dpe_size)) {
1281 				INFO(port->func.config->cdev,
1282 				     "Bad index: %#X\n", index);
1283 				goto err;
1284 			}
1285 
1286 			dg_len = dg_len2;
1287 			/*
1288 			 * wDatagramLength[0]
1289 			 * ethernet hdr + crc or larger than max frame size
1290 			 */
1291 			if ((dg_len < 14 + crc_len) ||
1292 					(dg_len > frame_max)) {
1293 				INFO(port->func.config->cdev,
1294 				     "Bad dgram length: %#X\n", dg_len);
1295 				goto err;
1296 			}
1297 			if (ncm->is_crc) {
1298 				uint32_t crc, crc2;
1299 
1300 				crc = get_unaligned_le32(skb->data +
1301 							 index + dg_len -
1302 							 crc_len);
1303 				crc2 = ~crc32_le(~0,
1304 						 skb->data + index,
1305 						 dg_len - crc_len);
1306 				if (crc != crc2) {
1307 					INFO(port->func.config->cdev,
1308 					     "Bad CRC\n");
1309 					goto err;
1310 				}
1311 			}
1312 
1313 			index2 = get_ncm(&tmp, opts->dgram_item_len);
1314 			dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1315 
1316 			/* wDatagramIndex[1] */
1317 			if (index2 > block_len - opts->dpe_size) {
1318 				INFO(port->func.config->cdev,
1319 				     "Bad index: %#X\n", index2);
1320 				goto err;
1321 			}
1322 
1323 			/*
1324 			 * Copy the data into a new skb.
1325 			 * This ensures the truesize is correct
1326 			 */
1327 			skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1328 							 dg_len - crc_len);
1329 			if (skb2 == NULL)
1330 				goto err;
1331 			skb_put_data(skb2, skb->data + index,
1332 				     dg_len - crc_len);
1333 
1334 			skb_queue_tail(list, skb2);
1335 
1336 			ndp_len -= 2 * (opts->dgram_item_len * 2);
1337 
1338 			dgram_counter++;
1339 			if (index2 == 0 || dg_len2 == 0)
1340 				break;
1341 		} while (ndp_len > 2 * (opts->dgram_item_len * 2));
1342 	} while (ndp_index);
1343 
1344 	dev_consume_skb_any(skb);
1345 
1346 	VDBG(port->func.config->cdev,
1347 	     "Parsed NTB with %d frames\n", dgram_counter);
1348 	return 0;
1349 err:
1350 	skb_queue_purge(list);
1351 	dev_kfree_skb_any(skb);
1352 	return ret;
1353 }
1354 
ncm_disable(struct usb_function * f)1355 static void ncm_disable(struct usb_function *f)
1356 {
1357 	struct f_ncm		*ncm = func_to_ncm(f);
1358 	struct usb_composite_dev *cdev = f->config->cdev;
1359 
1360 	DBG(cdev, "ncm deactivated\n");
1361 
1362 	if (ncm->port.in_ep->enabled) {
1363 		ncm->timer_stopping = true;
1364 		ncm->netdev = NULL;
1365 		gether_disconnect(&ncm->port);
1366 	}
1367 
1368 	if (ncm->notify->enabled) {
1369 		usb_ep_disable(ncm->notify);
1370 		ncm->notify->desc = NULL;
1371 	}
1372 }
1373 
1374 /*-------------------------------------------------------------------------*/
1375 
1376 /*
1377  * Callbacks let us notify the host about connect/disconnect when the
1378  * net device is opened or closed.
1379  *
1380  * For testing, note that link states on this side include both opened
1381  * and closed variants of:
1382  *
1383  *   - disconnected/unconfigured
1384  *   - configured but inactive (data alt 0)
1385  *   - configured and active (data alt 1)
1386  *
1387  * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1388  * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1389  * imply the host is actually polling the notification endpoint, and
1390  * likewise that "active" doesn't imply it's actually using the data
1391  * endpoints for traffic.
1392  */
1393 
ncm_open(struct gether * geth)1394 static void ncm_open(struct gether *geth)
1395 {
1396 	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1397 
1398 	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1399 
1400 	spin_lock(&ncm->lock);
1401 	ncm->is_open = true;
1402 	ncm_notify(ncm);
1403 	spin_unlock(&ncm->lock);
1404 }
1405 
ncm_close(struct gether * geth)1406 static void ncm_close(struct gether *geth)
1407 {
1408 	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1409 
1410 	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1411 
1412 	spin_lock(&ncm->lock);
1413 	ncm->is_open = false;
1414 	ncm_notify(ncm);
1415 	spin_unlock(&ncm->lock);
1416 }
1417 
1418 /*-------------------------------------------------------------------------*/
1419 
1420 /* ethernet function driver setup/binding */
1421 
ncm_bind(struct usb_configuration * c,struct usb_function * f)1422 static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1423 {
1424 	struct usb_composite_dev *cdev = c->cdev;
1425 	struct f_ncm		*ncm = func_to_ncm(f);
1426 	struct usb_string	*us;
1427 	int			status;
1428 	struct usb_ep		*ep;
1429 	struct f_ncm_opts	*ncm_opts;
1430 
1431 	if (!can_support_ecm(cdev->gadget))
1432 		return -EINVAL;
1433 
1434 	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1435 	/*
1436 	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
1437 	 * configurations are bound in sequence with list_for_each_entry,
1438 	 * in each configuration its functions are bound in sequence
1439 	 * with list_for_each_entry, so we assume no race condition
1440 	 * with regard to ncm_opts->bound access
1441 	 */
1442 	if (!ncm_opts->bound) {
1443 		mutex_lock(&ncm_opts->lock);
1444 		gether_set_gadget(ncm_opts->net, cdev->gadget);
1445 		status = gether_register_netdev(ncm_opts->net);
1446 		mutex_unlock(&ncm_opts->lock);
1447 		if (status)
1448 			return status;
1449 		ncm_opts->bound = true;
1450 	}
1451 	us = usb_gstrings_attach(cdev, ncm_strings,
1452 				 ARRAY_SIZE(ncm_string_defs));
1453 	if (IS_ERR(us))
1454 		return PTR_ERR(us);
1455 	ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1456 	ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1457 	ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1458 	ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1459 	ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1460 
1461 	/* allocate instance-specific interface IDs */
1462 	status = usb_interface_id(c, f);
1463 	if (status < 0)
1464 		goto fail;
1465 	ncm->ctrl_id = status;
1466 	ncm_iad_desc.bFirstInterface = status;
1467 
1468 	ncm_control_intf.bInterfaceNumber = status;
1469 	ncm_union_desc.bMasterInterface0 = status;
1470 
1471 	status = usb_interface_id(c, f);
1472 	if (status < 0)
1473 		goto fail;
1474 	ncm->data_id = status;
1475 
1476 	ncm_data_nop_intf.bInterfaceNumber = status;
1477 	ncm_data_intf.bInterfaceNumber = status;
1478 	ncm_union_desc.bSlaveInterface0 = status;
1479 
1480 	status = -ENODEV;
1481 
1482 	/* allocate instance-specific endpoints */
1483 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1484 	if (!ep)
1485 		goto fail;
1486 	ncm->port.in_ep = ep;
1487 
1488 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1489 	if (!ep)
1490 		goto fail;
1491 	ncm->port.out_ep = ep;
1492 
1493 	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1494 	if (!ep)
1495 		goto fail;
1496 	ncm->notify = ep;
1497 
1498 	status = -ENOMEM;
1499 
1500 	/* allocate notification request and buffer */
1501 	ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1502 	if (!ncm->notify_req)
1503 		goto fail;
1504 	ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1505 	if (!ncm->notify_req->buf)
1506 		goto fail;
1507 	ncm->notify_req->context = ncm;
1508 	ncm->notify_req->complete = ncm_notify_complete;
1509 
1510 	/*
1511 	 * support all relevant hardware speeds... we expect that when
1512 	 * hardware is dual speed, all bulk-capable endpoints work at
1513 	 * both speeds
1514 	 */
1515 	hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1516 	hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1517 	hs_ncm_notify_desc.bEndpointAddress =
1518 		fs_ncm_notify_desc.bEndpointAddress;
1519 
1520 	ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1521 	ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1522 	ss_ncm_notify_desc.bEndpointAddress =
1523 		fs_ncm_notify_desc.bEndpointAddress;
1524 
1525 	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1526 			ncm_ss_function, ncm_ss_function);
1527 	if (status)
1528 		goto fail;
1529 
1530 	/*
1531 	 * NOTE:  all that is done without knowing or caring about
1532 	 * the network link ... which is unavailable to this code
1533 	 * until we're activated via set_alt().
1534 	 */
1535 
1536 	ncm->port.open = ncm_open;
1537 	ncm->port.close = ncm_close;
1538 
1539 	hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
1540 	ncm->task_timer.function = ncm_tx_timeout;
1541 
1542 	DBG(cdev, "CDC Network: %s speed IN/%s OUT/%s NOTIFY/%s\n",
1543 			gadget_is_superspeed(c->cdev->gadget) ? "super" :
1544 			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
1545 			ncm->port.in_ep->name, ncm->port.out_ep->name,
1546 			ncm->notify->name);
1547 	return 0;
1548 
1549 fail:
1550 	if (ncm->notify_req) {
1551 		kfree(ncm->notify_req->buf);
1552 		usb_ep_free_request(ncm->notify, ncm->notify_req);
1553 	}
1554 
1555 	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1556 
1557 	return status;
1558 }
1559 
to_f_ncm_opts(struct config_item * item)1560 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1561 {
1562 	return container_of(to_config_group(item), struct f_ncm_opts,
1563 			    func_inst.group);
1564 }
1565 
1566 /* f_ncm_item_ops */
1567 USB_ETHERNET_CONFIGFS_ITEM(ncm);
1568 
1569 /* f_ncm_opts_dev_addr */
1570 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1571 
1572 /* f_ncm_opts_host_addr */
1573 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1574 
1575 /* f_ncm_opts_qmult */
1576 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1577 
1578 /* f_ncm_opts_ifname */
1579 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1580 
1581 static struct configfs_attribute *ncm_attrs[] = {
1582 	&ncm_opts_attr_dev_addr,
1583 	&ncm_opts_attr_host_addr,
1584 	&ncm_opts_attr_qmult,
1585 	&ncm_opts_attr_ifname,
1586 	NULL,
1587 };
1588 
1589 static const struct config_item_type ncm_func_type = {
1590 	.ct_item_ops	= &ncm_item_ops,
1591 	.ct_attrs	= ncm_attrs,
1592 	.ct_owner	= THIS_MODULE,
1593 };
1594 
ncm_free_inst(struct usb_function_instance * f)1595 static void ncm_free_inst(struct usb_function_instance *f)
1596 {
1597 	struct f_ncm_opts *opts;
1598 
1599 	opts = container_of(f, struct f_ncm_opts, func_inst);
1600 	if (opts->bound)
1601 		gether_cleanup(netdev_priv(opts->net));
1602 	else
1603 		free_netdev(opts->net);
1604 	kfree(opts);
1605 }
1606 
ncm_alloc_inst(void)1607 static struct usb_function_instance *ncm_alloc_inst(void)
1608 {
1609 	struct f_ncm_opts *opts;
1610 
1611 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1612 	if (!opts)
1613 		return ERR_PTR(-ENOMEM);
1614 	mutex_init(&opts->lock);
1615 	opts->func_inst.free_func_inst = ncm_free_inst;
1616 	opts->net = gether_setup_default();
1617 	if (IS_ERR(opts->net)) {
1618 		struct net_device *net = opts->net;
1619 		kfree(opts);
1620 		return ERR_CAST(net);
1621 	}
1622 
1623 	config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1624 
1625 	return &opts->func_inst;
1626 }
1627 
ncm_free(struct usb_function * f)1628 static void ncm_free(struct usb_function *f)
1629 {
1630 	struct f_ncm *ncm;
1631 	struct f_ncm_opts *opts;
1632 
1633 	ncm = func_to_ncm(f);
1634 	opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1635 	kfree(ncm);
1636 	mutex_lock(&opts->lock);
1637 	opts->refcnt--;
1638 	mutex_unlock(&opts->lock);
1639 }
1640 
ncm_unbind(struct usb_configuration * c,struct usb_function * f)1641 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1642 {
1643 	struct f_ncm *ncm = func_to_ncm(f);
1644 
1645 	DBG(c->cdev, "ncm unbind\n");
1646 
1647 	hrtimer_cancel(&ncm->task_timer);
1648 
1649 	ncm_string_defs[0].id = 0;
1650 	usb_free_all_descriptors(f);
1651 
1652 	if (atomic_read(&ncm->notify_count)) {
1653 		usb_ep_dequeue(ncm->notify, ncm->notify_req);
1654 		atomic_set(&ncm->notify_count, 0);
1655 	}
1656 
1657 	kfree(ncm->notify_req->buf);
1658 	usb_ep_free_request(ncm->notify, ncm->notify_req);
1659 }
1660 
ncm_alloc(struct usb_function_instance * fi)1661 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1662 {
1663 	struct f_ncm		*ncm;
1664 	struct f_ncm_opts	*opts;
1665 	int status;
1666 
1667 	/* allocate and initialize one new instance */
1668 	ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1669 	if (!ncm)
1670 		return ERR_PTR(-ENOMEM);
1671 
1672 	opts = container_of(fi, struct f_ncm_opts, func_inst);
1673 	mutex_lock(&opts->lock);
1674 	opts->refcnt++;
1675 
1676 	/* export host's Ethernet address in CDC format */
1677 	status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1678 				      sizeof(ncm->ethaddr));
1679 	if (status < 12) { /* strlen("01234567890a") */
1680 		kfree(ncm);
1681 		mutex_unlock(&opts->lock);
1682 		return ERR_PTR(-EINVAL);
1683 	}
1684 	ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1685 
1686 	spin_lock_init(&ncm->lock);
1687 	ncm_reset_values(ncm);
1688 	ncm->port.ioport = netdev_priv(opts->net);
1689 	mutex_unlock(&opts->lock);
1690 	ncm->port.is_fixed = true;
1691 	ncm->port.supports_multi_frame = true;
1692 
1693 	ncm->port.func.name = "cdc_network";
1694 	/* descriptors are per-instance copies */
1695 	ncm->port.func.bind = ncm_bind;
1696 	ncm->port.func.unbind = ncm_unbind;
1697 	ncm->port.func.set_alt = ncm_set_alt;
1698 	ncm->port.func.get_alt = ncm_get_alt;
1699 	ncm->port.func.setup = ncm_setup;
1700 	ncm->port.func.disable = ncm_disable;
1701 	ncm->port.func.free_func = ncm_free;
1702 
1703 	ncm->port.wrap = ncm_wrap_ntb;
1704 	ncm->port.unwrap = ncm_unwrap_ntb;
1705 
1706 	return &ncm->port.func;
1707 }
1708 
1709 DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1710 MODULE_LICENSE("GPL");
1711 MODULE_AUTHOR("Yauheni Kaliuta");
1712