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#include "configfs.h"
27
28/*
29 * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
30 * NCM is intended to be used with high-speed network attachments.
31 *
32 * Note that NCM requires the use of "alternate settings" for its data
33 * interface.  This means that the set_alt() method has real work to do,
34 * and also means that a get_alt() method is required.
35 */
36
37/* to trigger crc/non-crc ndp signature */
38
39#define NCM_NDP_HDR_CRC		0x01000000
40
41enum ncm_notify_state {
42	NCM_NOTIFY_NONE,		/* don't notify */
43	NCM_NOTIFY_CONNECT,		/* issue CONNECT next */
44	NCM_NOTIFY_SPEED,		/* issue SPEED_CHANGE next */
45};
46
47struct f_ncm {
48	struct gether			port;
49	u8				ctrl_id, data_id;
50
51	char				ethaddr[14];
52
53	struct usb_ep			*notify;
54	struct usb_request		*notify_req;
55	u8				notify_state;
56	atomic_t			notify_count;
57	bool				is_open;
58
59	const struct ndp_parser_opts	*parser_opts;
60	bool				is_crc;
61	u32				ndp_sign;
62
63	/*
64	 * for notification, it is accessed from both
65	 * callback and ethernet open/close
66	 */
67	spinlock_t			lock;
68
69	struct net_device		*netdev;
70
71	/* For multi-frame NDP TX */
72	struct sk_buff			*skb_tx_data;
73	struct sk_buff			*skb_tx_ndp;
74	u16				ndp_dgram_count;
75	struct hrtimer			task_timer;
76};
77
78static inline struct f_ncm *func_to_ncm(struct usb_function *f)
79{
80	return container_of(f, struct f_ncm, port.func);
81}
82
83/*-------------------------------------------------------------------------*/
84
85/*
86 * We cannot group frames so use just the minimal size which ok to put
87 * one max-size ethernet frame.
88 * If the host can group frames, allow it to do that, 16K is selected,
89 * because it's used by default by the current linux host driver
90 */
91#define NTB_DEFAULT_IN_SIZE	16384
92#define NTB_OUT_SIZE		16384
93
94/* Allocation for storing the NDP, 32 should suffice for a
95 * 16k packet. This allows a maximum of 32 * 507 Byte packets to
96 * be transmitted in a single 16kB skb, though when sending full size
97 * packets this limit will be plenty.
98 * Smaller packets are not likely to be trying to maximize the
99 * throughput and will be mstly sending smaller infrequent frames.
100 */
101#define TX_MAX_NUM_DPE		32
102
103/* Delay for the transmit to wait before sending an unfilled NTB frame. */
104#define TX_TIMEOUT_NSECS	300000
105
106#define FORMATS_SUPPORTED	(USB_CDC_NCM_NTB16_SUPPORTED |	\
107				 USB_CDC_NCM_NTB32_SUPPORTED)
108
109static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
110	.wLength = cpu_to_le16(sizeof(ntb_parameters)),
111	.bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
112	.dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
113	.wNdpInDivisor = cpu_to_le16(4),
114	.wNdpInPayloadRemainder = cpu_to_le16(0),
115	.wNdpInAlignment = cpu_to_le16(4),
116
117	.dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
118	.wNdpOutDivisor = cpu_to_le16(4),
119	.wNdpOutPayloadRemainder = cpu_to_le16(0),
120	.wNdpOutAlignment = cpu_to_le16(4),
121};
122
123/*
124 * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
125 * packet, to simplify cancellation; and a big transfer interval, to
126 * waste less bandwidth.
127 */
128
129#define NCM_STATUS_INTERVAL_MS		32
130#define NCM_STATUS_BYTECOUNT		16	/* 8 byte header + data */
131
132static struct usb_interface_assoc_descriptor ncm_iad_desc = {
133	.bLength =		sizeof ncm_iad_desc,
134	.bDescriptorType =	USB_DT_INTERFACE_ASSOCIATION,
135
136	/* .bFirstInterface =	DYNAMIC, */
137	.bInterfaceCount =	2,	/* control + data */
138	.bFunctionClass =	USB_CLASS_COMM,
139	.bFunctionSubClass =	USB_CDC_SUBCLASS_NCM,
140	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
141	/* .iFunction =		DYNAMIC */
142};
143
144/* interface descriptor: */
145
146static struct usb_interface_descriptor ncm_control_intf = {
147	.bLength =		sizeof ncm_control_intf,
148	.bDescriptorType =	USB_DT_INTERFACE,
149
150	/* .bInterfaceNumber = DYNAMIC */
151	.bNumEndpoints =	1,
152	.bInterfaceClass =	USB_CLASS_COMM,
153	.bInterfaceSubClass =	USB_CDC_SUBCLASS_NCM,
154	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
155	/* .iInterface = DYNAMIC */
156};
157
158static struct usb_cdc_header_desc ncm_header_desc = {
159	.bLength =		sizeof ncm_header_desc,
160	.bDescriptorType =	USB_DT_CS_INTERFACE,
161	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
162
163	.bcdCDC =		cpu_to_le16(0x0110),
164};
165
166static struct usb_cdc_union_desc ncm_union_desc = {
167	.bLength =		sizeof(ncm_union_desc),
168	.bDescriptorType =	USB_DT_CS_INTERFACE,
169	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
170	/* .bMasterInterface0 =	DYNAMIC */
171	/* .bSlaveInterface0 =	DYNAMIC */
172};
173
174static struct usb_cdc_ether_desc ecm_desc = {
175	.bLength =		sizeof ecm_desc,
176	.bDescriptorType =	USB_DT_CS_INTERFACE,
177	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
178
179	/* this descriptor actually adds value, surprise! */
180	/* .iMACAddress = DYNAMIC */
181	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
182	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
183	.wNumberMCFilters =	cpu_to_le16(0),
184	.bNumberPowerFilters =	0,
185};
186
187#define NCAPS	(USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
188
189static struct usb_cdc_ncm_desc ncm_desc = {
190	.bLength =		sizeof ncm_desc,
191	.bDescriptorType =	USB_DT_CS_INTERFACE,
192	.bDescriptorSubType =	USB_CDC_NCM_TYPE,
193
194	.bcdNcmVersion =	cpu_to_le16(0x0100),
195	/* can process SetEthernetPacketFilter */
196	.bmNetworkCapabilities = NCAPS,
197};
198
199/* the default data interface has no endpoints ... */
200
201static struct usb_interface_descriptor ncm_data_nop_intf = {
202	.bLength =		sizeof ncm_data_nop_intf,
203	.bDescriptorType =	USB_DT_INTERFACE,
204
205	.bInterfaceNumber =	1,
206	.bAlternateSetting =	0,
207	.bNumEndpoints =	0,
208	.bInterfaceClass =	USB_CLASS_CDC_DATA,
209	.bInterfaceSubClass =	0,
210	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
211	/* .iInterface = DYNAMIC */
212};
213
214/* ... but the "real" data interface has two bulk endpoints */
215
216static struct usb_interface_descriptor ncm_data_intf = {
217	.bLength =		sizeof ncm_data_intf,
218	.bDescriptorType =	USB_DT_INTERFACE,
219
220	.bInterfaceNumber =	1,
221	.bAlternateSetting =	1,
222	.bNumEndpoints =	2,
223	.bInterfaceClass =	USB_CLASS_CDC_DATA,
224	.bInterfaceSubClass =	0,
225	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
226	/* .iInterface = DYNAMIC */
227};
228
229/* full speed support: */
230
231static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
232	.bLength =		USB_DT_ENDPOINT_SIZE,
233	.bDescriptorType =	USB_DT_ENDPOINT,
234
235	.bEndpointAddress =	USB_DIR_IN,
236	.bmAttributes =		USB_ENDPOINT_XFER_INT,
237	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
238	.bInterval =		NCM_STATUS_INTERVAL_MS,
239};
240
241static struct usb_endpoint_descriptor fs_ncm_in_desc = {
242	.bLength =		USB_DT_ENDPOINT_SIZE,
243	.bDescriptorType =	USB_DT_ENDPOINT,
244
245	.bEndpointAddress =	USB_DIR_IN,
246	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
247};
248
249static struct usb_endpoint_descriptor fs_ncm_out_desc = {
250	.bLength =		USB_DT_ENDPOINT_SIZE,
251	.bDescriptorType =	USB_DT_ENDPOINT,
252
253	.bEndpointAddress =	USB_DIR_OUT,
254	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
255};
256
257static struct usb_descriptor_header *ncm_fs_function[] = {
258	(struct usb_descriptor_header *) &ncm_iad_desc,
259	/* CDC NCM control descriptors */
260	(struct usb_descriptor_header *) &ncm_control_intf,
261	(struct usb_descriptor_header *) &ncm_header_desc,
262	(struct usb_descriptor_header *) &ncm_union_desc,
263	(struct usb_descriptor_header *) &ecm_desc,
264	(struct usb_descriptor_header *) &ncm_desc,
265	(struct usb_descriptor_header *) &fs_ncm_notify_desc,
266	/* data interface, altsettings 0 and 1 */
267	(struct usb_descriptor_header *) &ncm_data_nop_intf,
268	(struct usb_descriptor_header *) &ncm_data_intf,
269	(struct usb_descriptor_header *) &fs_ncm_in_desc,
270	(struct usb_descriptor_header *) &fs_ncm_out_desc,
271	NULL,
272};
273
274/* high speed support: */
275
276static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
277	.bLength =		USB_DT_ENDPOINT_SIZE,
278	.bDescriptorType =	USB_DT_ENDPOINT,
279
280	.bEndpointAddress =	USB_DIR_IN,
281	.bmAttributes =		USB_ENDPOINT_XFER_INT,
282	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
283	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
284};
285static struct usb_endpoint_descriptor hs_ncm_in_desc = {
286	.bLength =		USB_DT_ENDPOINT_SIZE,
287	.bDescriptorType =	USB_DT_ENDPOINT,
288
289	.bEndpointAddress =	USB_DIR_IN,
290	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
291	.wMaxPacketSize =	cpu_to_le16(512),
292};
293
294static struct usb_endpoint_descriptor hs_ncm_out_desc = {
295	.bLength =		USB_DT_ENDPOINT_SIZE,
296	.bDescriptorType =	USB_DT_ENDPOINT,
297
298	.bEndpointAddress =	USB_DIR_OUT,
299	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
300	.wMaxPacketSize =	cpu_to_le16(512),
301};
302
303static struct usb_descriptor_header *ncm_hs_function[] = {
304	(struct usb_descriptor_header *) &ncm_iad_desc,
305	/* CDC NCM control descriptors */
306	(struct usb_descriptor_header *) &ncm_control_intf,
307	(struct usb_descriptor_header *) &ncm_header_desc,
308	(struct usb_descriptor_header *) &ncm_union_desc,
309	(struct usb_descriptor_header *) &ecm_desc,
310	(struct usb_descriptor_header *) &ncm_desc,
311	(struct usb_descriptor_header *) &hs_ncm_notify_desc,
312	/* data interface, altsettings 0 and 1 */
313	(struct usb_descriptor_header *) &ncm_data_nop_intf,
314	(struct usb_descriptor_header *) &ncm_data_intf,
315	(struct usb_descriptor_header *) &hs_ncm_in_desc,
316	(struct usb_descriptor_header *) &hs_ncm_out_desc,
317	NULL,
318};
319
320
321/* super speed support: */
322
323static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
324	.bLength =		USB_DT_ENDPOINT_SIZE,
325	.bDescriptorType =	USB_DT_ENDPOINT,
326
327	.bEndpointAddress =	USB_DIR_IN,
328	.bmAttributes =		USB_ENDPOINT_XFER_INT,
329	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
330	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
331};
332
333static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
334	.bLength =		sizeof(ss_ncm_notify_comp_desc),
335	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
336
337	/* the following 3 values can be tweaked if necessary */
338	/* .bMaxBurst =		0, */
339	/* .bmAttributes =	0, */
340	.wBytesPerInterval =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
341};
342
343static struct usb_endpoint_descriptor ss_ncm_in_desc = {
344	.bLength =		USB_DT_ENDPOINT_SIZE,
345	.bDescriptorType =	USB_DT_ENDPOINT,
346
347	.bEndpointAddress =	USB_DIR_IN,
348	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
349	.wMaxPacketSize =	cpu_to_le16(1024),
350};
351
352static struct usb_endpoint_descriptor ss_ncm_out_desc = {
353	.bLength =		USB_DT_ENDPOINT_SIZE,
354	.bDescriptorType =	USB_DT_ENDPOINT,
355
356	.bEndpointAddress =	USB_DIR_OUT,
357	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
358	.wMaxPacketSize =	cpu_to_le16(1024),
359};
360
361static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
362	.bLength =		sizeof(ss_ncm_bulk_comp_desc),
363	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
364
365	/* the following 2 values can be tweaked if necessary */
366	.bMaxBurst =		15,
367	/* .bmAttributes =	0, */
368};
369
370static struct usb_descriptor_header *ncm_ss_function[] = {
371	(struct usb_descriptor_header *) &ncm_iad_desc,
372	/* CDC NCM control descriptors */
373	(struct usb_descriptor_header *) &ncm_control_intf,
374	(struct usb_descriptor_header *) &ncm_header_desc,
375	(struct usb_descriptor_header *) &ncm_union_desc,
376	(struct usb_descriptor_header *) &ecm_desc,
377	(struct usb_descriptor_header *) &ncm_desc,
378	(struct usb_descriptor_header *) &ss_ncm_notify_desc,
379	(struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
380	/* data interface, altsettings 0 and 1 */
381	(struct usb_descriptor_header *) &ncm_data_nop_intf,
382	(struct usb_descriptor_header *) &ncm_data_intf,
383	(struct usb_descriptor_header *) &ss_ncm_in_desc,
384	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
385	(struct usb_descriptor_header *) &ss_ncm_out_desc,
386	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
387	NULL,
388};
389
390/* string descriptors: */
391
392#define STRING_CTRL_IDX	0
393#define STRING_MAC_IDX	1
394#define STRING_DATA_IDX	2
395#define STRING_IAD_IDX	3
396
397static struct usb_string ncm_string_defs[] = {
398	[STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
399	[STRING_MAC_IDX].s = "",
400	[STRING_DATA_IDX].s = "CDC Network Data",
401	[STRING_IAD_IDX].s = "CDC NCM",
402	{  } /* end of list */
403};
404
405static struct usb_gadget_strings ncm_string_table = {
406	.language =		0x0409,	/* en-us */
407	.strings =		ncm_string_defs,
408};
409
410static struct usb_gadget_strings *ncm_strings[] = {
411	&ncm_string_table,
412	NULL,
413};
414
415/*
416 * Here are options for NCM Datagram Pointer table (NDP) parser.
417 * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
418 * in NDP16 offsets and sizes fields are 1 16bit word wide,
419 * in NDP32 -- 2 16bit words wide. Also signatures are different.
420 * To make the parser code the same, put the differences in the structure,
421 * and switch pointers to the structures when the format is changed.
422 */
423
424struct ndp_parser_opts {
425	u32		nth_sign;
426	u32		ndp_sign;
427	unsigned	nth_size;
428	unsigned	ndp_size;
429	unsigned	dpe_size;
430	unsigned	ndplen_align;
431	/* sizes in u16 units */
432	unsigned	dgram_item_len; /* index or length */
433	unsigned	block_length;
434	unsigned	ndp_index;
435	unsigned	reserved1;
436	unsigned	reserved2;
437	unsigned	next_ndp_index;
438};
439
440static const struct ndp_parser_opts ndp16_opts = {
441	.nth_sign = USB_CDC_NCM_NTH16_SIGN,
442	.ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,
443	.nth_size = sizeof(struct usb_cdc_ncm_nth16),
444	.ndp_size = sizeof(struct usb_cdc_ncm_ndp16),
445	.dpe_size = sizeof(struct usb_cdc_ncm_dpe16),
446	.ndplen_align = 4,
447	.dgram_item_len = 1,
448	.block_length = 1,
449	.ndp_index = 1,
450	.reserved1 = 0,
451	.reserved2 = 0,
452	.next_ndp_index = 1,
453};
454
455static const struct ndp_parser_opts ndp32_opts = {
456	.nth_sign = USB_CDC_NCM_NTH32_SIGN,
457	.ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,
458	.nth_size = sizeof(struct usb_cdc_ncm_nth32),
459	.ndp_size = sizeof(struct usb_cdc_ncm_ndp32),
460	.dpe_size = sizeof(struct usb_cdc_ncm_dpe32),
461	.ndplen_align = 8,
462	.dgram_item_len = 2,
463	.block_length = 2,
464	.ndp_index = 2,
465	.reserved1 = 1,
466	.reserved2 = 2,
467	.next_ndp_index = 2,
468};
469
470static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
471{
472	switch (size) {
473	case 1:
474		put_unaligned_le16((u16)val, *p);
475		break;
476	case 2:
477		put_unaligned_le32((u32)val, *p);
478
479		break;
480	default:
481		BUG();
482	}
483
484	*p += size;
485}
486
487static inline unsigned get_ncm(__le16 **p, unsigned size)
488{
489	unsigned tmp;
490
491	switch (size) {
492	case 1:
493		tmp = get_unaligned_le16(*p);
494		break;
495	case 2:
496		tmp = get_unaligned_le32(*p);
497		break;
498	default:
499		BUG();
500	}
501
502	*p += size;
503	return tmp;
504}
505
506/*-------------------------------------------------------------------------*/
507
508static inline void ncm_reset_values(struct f_ncm *ncm)
509{
510	ncm->parser_opts = &ndp16_opts;
511	ncm->is_crc = false;
512	ncm->ndp_sign = ncm->parser_opts->ndp_sign;
513	ncm->port.cdc_filter = DEFAULT_FILTER;
514
515	/* doesn't make sense for ncm, fixed size used */
516	ncm->port.header_len = 0;
517
518	ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
519	ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
520}
521
522/*
523 * Context: ncm->lock held
524 */
525static void ncm_do_notify(struct f_ncm *ncm)
526{
527	struct usb_request		*req = ncm->notify_req;
528	struct usb_cdc_notification	*event;
529	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
530	__le32				*data;
531	int				status;
532
533	/* notification already in flight? */
534	if (atomic_read(&ncm->notify_count))
535		return;
536
537	event = req->buf;
538	switch (ncm->notify_state) {
539	case NCM_NOTIFY_NONE:
540		return;
541
542	case NCM_NOTIFY_CONNECT:
543		event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
544		if (ncm->is_open)
545			event->wValue = cpu_to_le16(1);
546		else
547			event->wValue = cpu_to_le16(0);
548		event->wLength = 0;
549		req->length = sizeof *event;
550
551		DBG(cdev, "notify connect %s\n",
552				ncm->is_open ? "true" : "false");
553		ncm->notify_state = NCM_NOTIFY_NONE;
554		break;
555
556	case NCM_NOTIFY_SPEED:
557		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
558		event->wValue = cpu_to_le16(0);
559		event->wLength = cpu_to_le16(8);
560		req->length = NCM_STATUS_BYTECOUNT;
561
562		/* SPEED_CHANGE data is up/down speeds in bits/sec */
563		data = req->buf + sizeof *event;
564		data[0] = cpu_to_le32(gether_bitrate(cdev->gadget));
565		data[1] = data[0];
566
567		DBG(cdev, "notify speed %u\n", gether_bitrate(cdev->gadget));
568		ncm->notify_state = NCM_NOTIFY_CONNECT;
569		break;
570	}
571	event->bmRequestType = 0xA1;
572	event->wIndex = cpu_to_le16(ncm->ctrl_id);
573
574	atomic_inc(&ncm->notify_count);
575
576	/*
577	 * In double buffering if there is a space in FIFO,
578	 * completion callback can be called right after the call,
579	 * so unlocking
580	 */
581	spin_unlock(&ncm->lock);
582	status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
583	spin_lock(&ncm->lock);
584	if (status < 0) {
585		atomic_dec(&ncm->notify_count);
586		DBG(cdev, "notify --> %d\n", status);
587	}
588}
589
590/*
591 * Context: ncm->lock held
592 */
593static void ncm_notify(struct f_ncm *ncm)
594{
595	/*
596	 * NOTE on most versions of Linux, host side cdc-ethernet
597	 * won't listen for notifications until its netdevice opens.
598	 * The first notification then sits in the FIFO for a long
599	 * time, and the second one is queued.
600	 *
601	 * If ncm_notify() is called before the second (CONNECT)
602	 * notification is sent, then it will reset to send the SPEED
603	 * notificaion again (and again, and again), but it's not a problem
604	 */
605	ncm->notify_state = NCM_NOTIFY_SPEED;
606	ncm_do_notify(ncm);
607}
608
609static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
610{
611	struct f_ncm			*ncm = req->context;
612	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
613	struct usb_cdc_notification	*event = req->buf;
614
615	spin_lock(&ncm->lock);
616	switch (req->status) {
617	case 0:
618		VDBG(cdev, "Notification %02x sent\n",
619		     event->bNotificationType);
620		atomic_dec(&ncm->notify_count);
621		break;
622	case -ECONNRESET:
623	case -ESHUTDOWN:
624		atomic_set(&ncm->notify_count, 0);
625		ncm->notify_state = NCM_NOTIFY_NONE;
626		break;
627	default:
628		DBG(cdev, "event %02x --> %d\n",
629			event->bNotificationType, req->status);
630		atomic_dec(&ncm->notify_count);
631		break;
632	}
633	ncm_do_notify(ncm);
634	spin_unlock(&ncm->lock);
635}
636
637static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
638{
639	/* now for SET_NTB_INPUT_SIZE only */
640	unsigned		in_size;
641	struct usb_function	*f = req->context;
642	struct f_ncm		*ncm = func_to_ncm(f);
643	struct usb_composite_dev *cdev = f->config->cdev;
644
645	req->context = NULL;
646	if (req->status || req->actual != req->length) {
647		DBG(cdev, "Bad control-OUT transfer\n");
648		goto invalid;
649	}
650
651	in_size = get_unaligned_le32(req->buf);
652	if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
653	    in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
654		DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
655		goto invalid;
656	}
657
658	ncm->port.fixed_in_len = in_size;
659	VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
660	return;
661
662invalid:
663	usb_ep_set_halt(ep);
664	return;
665}
666
667static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
668{
669	struct f_ncm		*ncm = func_to_ncm(f);
670	struct usb_composite_dev *cdev = f->config->cdev;
671	struct usb_request	*req = cdev->req;
672	int			value = -EOPNOTSUPP;
673	u16			w_index = le16_to_cpu(ctrl->wIndex);
674	u16			w_value = le16_to_cpu(ctrl->wValue);
675	u16			w_length = le16_to_cpu(ctrl->wLength);
676
677	/*
678	 * composite driver infrastructure handles everything except
679	 * CDC class messages; interface activation uses set_alt().
680	 */
681	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
682	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
683			| USB_CDC_SET_ETHERNET_PACKET_FILTER:
684		/*
685		 * see 6.2.30: no data, wIndex = interface,
686		 * wValue = packet filter bitmap
687		 */
688		if (w_length != 0 || w_index != ncm->ctrl_id)
689			goto invalid;
690		DBG(cdev, "packet filter %02x\n", w_value);
691		/*
692		 * REVISIT locking of cdc_filter.  This assumes the UDC
693		 * driver won't have a concurrent packet TX irq running on
694		 * another CPU; or that if it does, this write is atomic...
695		 */
696		ncm->port.cdc_filter = w_value;
697		value = 0;
698		break;
699	/*
700	 * and optionally:
701	 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
702	 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
703	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
704	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
705	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
706	 * case USB_CDC_GET_ETHERNET_STATISTIC:
707	 */
708
709	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
710		| USB_CDC_GET_NTB_PARAMETERS:
711
712		if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
713			goto invalid;
714		value = w_length > sizeof ntb_parameters ?
715			sizeof ntb_parameters : w_length;
716		memcpy(req->buf, &ntb_parameters, value);
717		VDBG(cdev, "Host asked NTB parameters\n");
718		break;
719
720	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
721		| USB_CDC_GET_NTB_INPUT_SIZE:
722
723		if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
724			goto invalid;
725		put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
726		value = 4;
727		VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
728		     ncm->port.fixed_in_len);
729		break;
730
731	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
732		| USB_CDC_SET_NTB_INPUT_SIZE:
733	{
734		if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
735			goto invalid;
736		req->complete = ncm_ep0out_complete;
737		req->length = w_length;
738		req->context = f;
739
740		value = req->length;
741		break;
742	}
743
744	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
745		| USB_CDC_GET_NTB_FORMAT:
746	{
747		uint16_t format;
748
749		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
750			goto invalid;
751		format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
752		put_unaligned_le16(format, req->buf);
753		value = 2;
754		VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
755		break;
756	}
757
758	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
759		| USB_CDC_SET_NTB_FORMAT:
760	{
761		if (w_length != 0 || w_index != ncm->ctrl_id)
762			goto invalid;
763		switch (w_value) {
764		case 0x0000:
765			ncm->parser_opts = &ndp16_opts;
766			DBG(cdev, "NCM16 selected\n");
767			break;
768		case 0x0001:
769			ncm->parser_opts = &ndp32_opts;
770			DBG(cdev, "NCM32 selected\n");
771			break;
772		default:
773			goto invalid;
774		}
775		value = 0;
776		break;
777	}
778	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
779		| USB_CDC_GET_CRC_MODE:
780	{
781		uint16_t is_crc;
782
783		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
784			goto invalid;
785		is_crc = ncm->is_crc ? 0x0001 : 0x0000;
786		put_unaligned_le16(is_crc, req->buf);
787		value = 2;
788		VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
789		break;
790	}
791
792	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
793		| USB_CDC_SET_CRC_MODE:
794	{
795		if (w_length != 0 || w_index != ncm->ctrl_id)
796			goto invalid;
797		switch (w_value) {
798		case 0x0000:
799			ncm->is_crc = false;
800			DBG(cdev, "non-CRC mode selected\n");
801			break;
802		case 0x0001:
803			ncm->is_crc = true;
804			DBG(cdev, "CRC mode selected\n");
805			break;
806		default:
807			goto invalid;
808		}
809		value = 0;
810		break;
811	}
812
813	/* and disabled in ncm descriptor: */
814	/* case USB_CDC_GET_NET_ADDRESS: */
815	/* case USB_CDC_SET_NET_ADDRESS: */
816	/* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
817	/* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
818
819	default:
820invalid:
821		DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
822			ctrl->bRequestType, ctrl->bRequest,
823			w_value, w_index, w_length);
824	}
825	ncm->ndp_sign = ncm->parser_opts->ndp_sign |
826		(ncm->is_crc ? NCM_NDP_HDR_CRC : 0);
827
828	/* respond with data transfer or status phase? */
829	if (value >= 0) {
830		DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
831			ctrl->bRequestType, ctrl->bRequest,
832			w_value, w_index, w_length);
833		req->zero = 0;
834		req->length = value;
835		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
836		if (value < 0)
837			ERROR(cdev, "ncm req %02x.%02x response err %d\n",
838					ctrl->bRequestType, ctrl->bRequest,
839					value);
840	}
841
842	/* device either stalls (value < 0) or reports success */
843	return value;
844}
845
846
847static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
848{
849	struct f_ncm		*ncm = func_to_ncm(f);
850	struct usb_composite_dev *cdev = f->config->cdev;
851
852	/* Control interface has only altsetting 0 */
853	if (intf == ncm->ctrl_id) {
854		if (alt != 0)
855			goto fail;
856
857		DBG(cdev, "reset ncm control %d\n", intf);
858		usb_ep_disable(ncm->notify);
859
860		if (!(ncm->notify->desc)) {
861			DBG(cdev, "init ncm ctrl %d\n", intf);
862			if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
863				goto fail;
864		}
865		usb_ep_enable(ncm->notify);
866
867	/* Data interface has two altsettings, 0 and 1 */
868	} else if (intf == ncm->data_id) {
869		if (alt > 1)
870			goto fail;
871
872		if (ncm->port.in_ep->enabled) {
873			DBG(cdev, "reset ncm\n");
874			ncm->netdev = NULL;
875			gether_disconnect(&ncm->port);
876			ncm_reset_values(ncm);
877		}
878
879		/*
880		 * CDC Network only sends data in non-default altsettings.
881		 * Changing altsettings resets filters, statistics, etc.
882		 */
883		if (alt == 1) {
884			struct net_device	*net;
885
886			if (!ncm->port.in_ep->desc ||
887			    !ncm->port.out_ep->desc) {
888				DBG(cdev, "init ncm\n");
889				if (config_ep_by_speed(cdev->gadget, f,
890						       ncm->port.in_ep) ||
891				    config_ep_by_speed(cdev->gadget, f,
892						       ncm->port.out_ep)) {
893					ncm->port.in_ep->desc = NULL;
894					ncm->port.out_ep->desc = NULL;
895					goto fail;
896				}
897			}
898
899			/* TODO */
900			/* Enable zlps by default for NCM conformance;
901			 * override for musb_hdrc (avoids txdma ovhead)
902			 */
903			ncm->port.is_zlp_ok =
904				gadget_is_zlp_supported(cdev->gadget);
905			ncm->port.cdc_filter = DEFAULT_FILTER;
906			DBG(cdev, "activate ncm\n");
907			net = gether_connect(&ncm->port);
908			if (IS_ERR(net))
909				return PTR_ERR(net);
910			ncm->netdev = net;
911		}
912
913		spin_lock(&ncm->lock);
914		ncm_notify(ncm);
915		spin_unlock(&ncm->lock);
916	} else
917		goto fail;
918
919	return 0;
920fail:
921	return -EINVAL;
922}
923
924/*
925 * Because the data interface supports multiple altsettings,
926 * this NCM function *MUST* implement a get_alt() method.
927 */
928static int ncm_get_alt(struct usb_function *f, unsigned intf)
929{
930	struct f_ncm		*ncm = func_to_ncm(f);
931
932	if (intf == ncm->ctrl_id)
933		return 0;
934	return ncm->port.in_ep->enabled ? 1 : 0;
935}
936
937static struct sk_buff *package_for_tx(struct f_ncm *ncm)
938{
939	__le16		*ntb_iter;
940	struct sk_buff	*skb2 = NULL;
941	unsigned	ndp_pad;
942	unsigned	ndp_index;
943	unsigned	new_len;
944
945	const struct ndp_parser_opts *opts = ncm->parser_opts;
946	const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
947	const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
948
949	/* Stop the timer */
950	hrtimer_try_to_cancel(&ncm->task_timer);
951
952	ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
953			ncm->skb_tx_data->len;
954	ndp_index = ncm->skb_tx_data->len + ndp_pad;
955	new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
956
957	/* Set the final BlockLength and wNdpIndex */
958	ntb_iter = (void *) ncm->skb_tx_data->data;
959	/* Increment pointer to BlockLength */
960	ntb_iter += 2 + 1 + 1;
961	put_ncm(&ntb_iter, opts->block_length, new_len);
962	put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
963
964	/* Set the final NDP wLength */
965	new_len = opts->ndp_size +
966			(ncm->ndp_dgram_count * dgram_idx_len);
967	ncm->ndp_dgram_count = 0;
968	/* Increment from start to wLength */
969	ntb_iter = (void *) ncm->skb_tx_ndp->data;
970	ntb_iter += 2;
971	put_unaligned_le16(new_len, ntb_iter);
972
973	/* Merge the skbs */
974	swap(skb2, ncm->skb_tx_data);
975	if (ncm->skb_tx_data) {
976		dev_consume_skb_any(ncm->skb_tx_data);
977		ncm->skb_tx_data = NULL;
978	}
979
980	/* Insert NDP alignment. */
981	skb_put_zero(skb2, ndp_pad);
982
983	/* Copy NTB across. */
984	skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
985	dev_consume_skb_any(ncm->skb_tx_ndp);
986	ncm->skb_tx_ndp = NULL;
987
988	/* Insert zero'd datagram. */
989	skb_put_zero(skb2, dgram_idx_len);
990
991	return skb2;
992}
993
994static struct sk_buff *ncm_wrap_ntb(struct gether *port,
995				    struct sk_buff *skb)
996{
997	struct f_ncm	*ncm = func_to_ncm(&port->func);
998	struct sk_buff	*skb2 = NULL;
999
1000	if (skb) {
1001		int		ncb_len = 0;
1002		__le16		*ntb_data;
1003		__le16		*ntb_ndp;
1004		int		dgram_pad;
1005
1006		unsigned	max_size = ncm->port.fixed_in_len;
1007		const struct ndp_parser_opts *opts = ncm->parser_opts;
1008		const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1009		const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1010		const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1011		const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1012
1013		/* Add the CRC if required up front */
1014		if (ncm->is_crc) {
1015			uint32_t	crc;
1016			__le16		*crc_pos;
1017
1018			crc = ~crc32_le(~0,
1019					skb->data,
1020					skb->len);
1021			crc_pos = skb_put(skb, sizeof(uint32_t));
1022			put_unaligned_le32(crc, crc_pos);
1023		}
1024
1025		/* If the new skb is too big for the current NCM NTB then
1026		 * set the current stored skb to be sent now and clear it
1027		 * ready for new data.
1028		 * NOTE: Assume maximum align for speed of calculation.
1029		 */
1030		if (ncm->skb_tx_data
1031		    && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1032		    || (ncm->skb_tx_data->len +
1033		    div + rem + skb->len +
1034		    ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1035		    > max_size)) {
1036			skb2 = package_for_tx(ncm);
1037			if (!skb2)
1038				goto err;
1039		}
1040
1041		if (!ncm->skb_tx_data) {
1042			ncb_len = opts->nth_size;
1043			dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1044			ncb_len += dgram_pad;
1045
1046			/* Create a new skb for the NTH and datagrams. */
1047			ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1048			if (!ncm->skb_tx_data)
1049				goto err;
1050
1051			ncm->skb_tx_data->dev = ncm->netdev;
1052			ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1053			/* dwSignature */
1054			put_unaligned_le32(opts->nth_sign, ntb_data);
1055			ntb_data += 2;
1056			/* wHeaderLength */
1057			put_unaligned_le16(opts->nth_size, ntb_data++);
1058
1059			/* Allocate an skb for storing the NDP,
1060			 * TX_MAX_NUM_DPE should easily suffice for a
1061			 * 16k packet.
1062			 */
1063			ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1064						    + opts->dpe_size
1065						    * TX_MAX_NUM_DPE),
1066						    GFP_ATOMIC);
1067			if (!ncm->skb_tx_ndp)
1068				goto err;
1069
1070			ncm->skb_tx_ndp->dev = ncm->netdev;
1071			ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1072			memset(ntb_ndp, 0, ncb_len);
1073			/* dwSignature */
1074			put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1075			ntb_ndp += 2;
1076
1077			/* There is always a zeroed entry */
1078			ncm->ndp_dgram_count = 1;
1079
1080			/* Note: we skip opts->next_ndp_index */
1081
1082			/* Start the timer. */
1083			hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1084				      HRTIMER_MODE_REL_SOFT);
1085		}
1086
1087		/* Add the datagram position entries */
1088		ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1089
1090		ncb_len = ncm->skb_tx_data->len;
1091		dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1092		ncb_len += dgram_pad;
1093
1094		/* (d)wDatagramIndex */
1095		put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1096		/* (d)wDatagramLength */
1097		put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1098		ncm->ndp_dgram_count++;
1099
1100		/* Add the new data to the skb */
1101		skb_put_zero(ncm->skb_tx_data, dgram_pad);
1102		skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1103		dev_consume_skb_any(skb);
1104		skb = NULL;
1105
1106	} else if (ncm->skb_tx_data) {
1107		/* If we get here ncm_wrap_ntb() was called with NULL skb,
1108		 * because eth_start_xmit() was called with NULL skb by
1109		 * ncm_tx_timeout() - hence, this is our signal to flush/send.
1110		 */
1111		skb2 = package_for_tx(ncm);
1112		if (!skb2)
1113			goto err;
1114	}
1115
1116	return skb2;
1117
1118err:
1119	ncm->netdev->stats.tx_dropped++;
1120
1121	if (skb)
1122		dev_kfree_skb_any(skb);
1123	if (ncm->skb_tx_data)
1124		dev_kfree_skb_any(ncm->skb_tx_data);
1125	if (ncm->skb_tx_ndp)
1126		dev_kfree_skb_any(ncm->skb_tx_ndp);
1127
1128	return NULL;
1129}
1130
1131/*
1132 * The transmit should only be run if no skb data has been sent
1133 * for a certain duration.
1134 */
1135static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1136{
1137	struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1138	struct net_device *netdev = READ_ONCE(ncm->netdev);
1139
1140	if (netdev) {
1141		/* XXX This allowance of a NULL skb argument to ndo_start_xmit
1142		 * XXX is not sane.  The gadget layer should be redesigned so
1143		 * XXX that the dev->wrap() invocations to build SKBs is transparent
1144		 * XXX and performed in some way outside of the ndo_start_xmit
1145		 * XXX interface.
1146		 *
1147		 * This will call directly into u_ether's eth_start_xmit()
1148		 */
1149		netdev->netdev_ops->ndo_start_xmit(NULL, netdev);
1150	}
1151	return HRTIMER_NORESTART;
1152}
1153
1154static int ncm_unwrap_ntb(struct gether *port,
1155			  struct sk_buff *skb,
1156			  struct sk_buff_head *list)
1157{
1158	struct f_ncm	*ncm = func_to_ncm(&port->func);
1159	unsigned char	*ntb_ptr = skb->data;
1160	__le16		*tmp;
1161	unsigned	index, index2;
1162	int		ndp_index;
1163	unsigned	dg_len, dg_len2;
1164	unsigned	ndp_len;
1165	unsigned	block_len;
1166	struct sk_buff	*skb2;
1167	int		ret = -EINVAL;
1168	unsigned	ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1169	unsigned	frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
1170	const struct ndp_parser_opts *opts = ncm->parser_opts;
1171	unsigned	crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1172	int		dgram_counter;
1173	int		to_process = skb->len;
1174
1175parse_ntb:
1176	tmp = (__le16 *)ntb_ptr;
1177
1178	/* dwSignature */
1179	if (get_unaligned_le32(tmp) != opts->nth_sign) {
1180		INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1181			skb->len);
1182		print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1183			       skb->data, 32, false);
1184
1185		goto err;
1186	}
1187	tmp += 2;
1188	/* wHeaderLength */
1189	if (get_unaligned_le16(tmp++) != opts->nth_size) {
1190		INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1191		goto err;
1192	}
1193	tmp++; /* skip wSequence */
1194
1195	block_len = get_ncm(&tmp, opts->block_length);
1196	/* (d)wBlockLength */
1197	if (block_len > ntb_max) {
1198		INFO(port->func.config->cdev, "OUT size exceeded\n");
1199		goto err;
1200	}
1201
1202	ndp_index = get_ncm(&tmp, opts->ndp_index);
1203
1204	/* Run through all the NDP's in the NTB */
1205	do {
1206		/*
1207		 * NCM 3.2
1208		 * dwNdpIndex
1209		 */
1210		if (((ndp_index % 4) != 0) ||
1211				(ndp_index < opts->nth_size) ||
1212				(ndp_index > (block_len -
1213					      opts->ndp_size))) {
1214			INFO(port->func.config->cdev, "Bad index: %#X\n",
1215			     ndp_index);
1216			goto err;
1217		}
1218
1219		/*
1220		 * walk through NDP
1221		 * dwSignature
1222		 */
1223		tmp = (__le16 *)(ntb_ptr + ndp_index);
1224		if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1225			INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1226			goto err;
1227		}
1228		tmp += 2;
1229
1230		ndp_len = get_unaligned_le16(tmp++);
1231		/*
1232		 * NCM 3.3.1
1233		 * wLength
1234		 * entry is 2 items
1235		 * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1236		 * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1237		 * Each entry is a dgram index and a dgram length.
1238		 */
1239		if ((ndp_len < opts->ndp_size
1240				+ 2 * 2 * (opts->dgram_item_len * 2)) ||
1241				(ndp_len % opts->ndplen_align != 0)) {
1242			INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1243			     ndp_len);
1244			goto err;
1245		}
1246		tmp += opts->reserved1;
1247		/* Check for another NDP (d)wNextNdpIndex */
1248		ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1249		tmp += opts->reserved2;
1250
1251		ndp_len -= opts->ndp_size;
1252		index2 = get_ncm(&tmp, opts->dgram_item_len);
1253		dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1254		dgram_counter = 0;
1255
1256		do {
1257			index = index2;
1258			/* wDatagramIndex[0] */
1259			if ((index < opts->nth_size) ||
1260					(index > block_len - opts->dpe_size)) {
1261				INFO(port->func.config->cdev,
1262				     "Bad index: %#X\n", index);
1263				goto err;
1264			}
1265
1266			dg_len = dg_len2;
1267			/*
1268			 * wDatagramLength[0]
1269			 * ethernet hdr + crc or larger than max frame size
1270			 */
1271			if ((dg_len < 14 + crc_len) ||
1272					(dg_len > frame_max)) {
1273				INFO(port->func.config->cdev,
1274				     "Bad dgram length: %#X\n", dg_len);
1275				goto err;
1276			}
1277			if (ncm->is_crc) {
1278				uint32_t crc, crc2;
1279
1280				crc = get_unaligned_le32(ntb_ptr +
1281							 index + dg_len -
1282							 crc_len);
1283				crc2 = ~crc32_le(~0,
1284						 ntb_ptr + index,
1285						 dg_len - crc_len);
1286				if (crc != crc2) {
1287					INFO(port->func.config->cdev,
1288					     "Bad CRC\n");
1289					goto err;
1290				}
1291			}
1292
1293			index2 = get_ncm(&tmp, opts->dgram_item_len);
1294			dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1295
1296			/* wDatagramIndex[1] */
1297			if (index2 > block_len - opts->dpe_size) {
1298				INFO(port->func.config->cdev,
1299				     "Bad index: %#X\n", index2);
1300				goto err;
1301			}
1302
1303			/*
1304			 * Copy the data into a new skb.
1305			 * This ensures the truesize is correct
1306			 */
1307			skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1308							 dg_len - crc_len);
1309			if (skb2 == NULL)
1310				goto err;
1311			skb_put_data(skb2, ntb_ptr + index,
1312				     dg_len - crc_len);
1313
1314			skb_queue_tail(list, skb2);
1315
1316			ndp_len -= 2 * (opts->dgram_item_len * 2);
1317
1318			dgram_counter++;
1319			if (index2 == 0 || dg_len2 == 0)
1320				break;
1321		} while (ndp_len > 2 * (opts->dgram_item_len * 2));
1322	} while (ndp_index);
1323
1324	VDBG(port->func.config->cdev,
1325	     "Parsed NTB with %d frames\n", dgram_counter);
1326
1327	to_process -= block_len;
1328
1329	/*
1330	 * Windows NCM driver avoids USB ZLPs by adding a 1-byte
1331	 * zero pad as needed.
1332	 */
1333	if (to_process == 1 &&
1334	    (*(unsigned char *)(ntb_ptr + block_len) == 0x00)) {
1335		to_process--;
1336	} else if (to_process > 0) {
1337		ntb_ptr = (unsigned char *)(ntb_ptr + block_len);
1338		goto parse_ntb;
1339	}
1340
1341	dev_consume_skb_any(skb);
1342
1343	return 0;
1344err:
1345	skb_queue_purge(list);
1346	dev_kfree_skb_any(skb);
1347	return ret;
1348}
1349
1350static void ncm_disable(struct usb_function *f)
1351{
1352	struct f_ncm		*ncm = func_to_ncm(f);
1353	struct usb_composite_dev *cdev = f->config->cdev;
1354
1355	DBG(cdev, "ncm deactivated\n");
1356
1357	if (ncm->port.in_ep->enabled) {
1358		ncm->netdev = NULL;
1359		gether_disconnect(&ncm->port);
1360	}
1361
1362	if (ncm->notify->enabled) {
1363		usb_ep_disable(ncm->notify);
1364		ncm->notify->desc = NULL;
1365	}
1366}
1367
1368/*-------------------------------------------------------------------------*/
1369
1370/*
1371 * Callbacks let us notify the host about connect/disconnect when the
1372 * net device is opened or closed.
1373 *
1374 * For testing, note that link states on this side include both opened
1375 * and closed variants of:
1376 *
1377 *   - disconnected/unconfigured
1378 *   - configured but inactive (data alt 0)
1379 *   - configured and active (data alt 1)
1380 *
1381 * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1382 * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1383 * imply the host is actually polling the notification endpoint, and
1384 * likewise that "active" doesn't imply it's actually using the data
1385 * endpoints for traffic.
1386 */
1387
1388static void ncm_open(struct gether *geth)
1389{
1390	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1391
1392	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1393
1394	spin_lock(&ncm->lock);
1395	ncm->is_open = true;
1396	ncm_notify(ncm);
1397	spin_unlock(&ncm->lock);
1398}
1399
1400static void ncm_close(struct gether *geth)
1401{
1402	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1403
1404	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1405
1406	spin_lock(&ncm->lock);
1407	ncm->is_open = false;
1408	ncm_notify(ncm);
1409	spin_unlock(&ncm->lock);
1410}
1411
1412/*-------------------------------------------------------------------------*/
1413
1414/* ethernet function driver setup/binding */
1415
1416static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1417{
1418	struct usb_composite_dev *cdev = c->cdev;
1419	struct f_ncm		*ncm = func_to_ncm(f);
1420	struct usb_string	*us;
1421	int			status = 0;
1422	struct usb_ep		*ep;
1423	struct f_ncm_opts	*ncm_opts;
1424
1425	if (!can_support_ecm(cdev->gadget))
1426		return -EINVAL;
1427
1428	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1429
1430	if (cdev->use_os_string) {
1431		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
1432					   GFP_KERNEL);
1433		if (!f->os_desc_table)
1434			return -ENOMEM;
1435		f->os_desc_n = 1;
1436		f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
1437	}
1438
1439	mutex_lock(&ncm_opts->lock);
1440	gether_set_gadget(ncm_opts->net, cdev->gadget);
1441	if (!ncm_opts->bound)
1442		status = gether_register_netdev(ncm_opts->net);
1443	mutex_unlock(&ncm_opts->lock);
1444
1445	if (status)
1446		goto fail;
1447
1448	ncm_opts->bound = true;
1449
1450	us = usb_gstrings_attach(cdev, ncm_strings,
1451				 ARRAY_SIZE(ncm_string_defs));
1452	if (IS_ERR(us)) {
1453		status = PTR_ERR(us);
1454		goto fail;
1455	}
1456	ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1457	ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1458	ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1459	ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1460	ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1461
1462	/* allocate instance-specific interface IDs */
1463	status = usb_interface_id(c, f);
1464	if (status < 0)
1465		goto fail;
1466	ncm->ctrl_id = status;
1467	ncm_iad_desc.bFirstInterface = status;
1468
1469	ncm_control_intf.bInterfaceNumber = status;
1470	ncm_union_desc.bMasterInterface0 = status;
1471
1472	if (cdev->use_os_string)
1473		f->os_desc_table[0].if_id =
1474			ncm_iad_desc.bFirstInterface;
1475
1476	status = usb_interface_id(c, f);
1477	if (status < 0)
1478		goto fail;
1479	ncm->data_id = status;
1480
1481	ncm_data_nop_intf.bInterfaceNumber = status;
1482	ncm_data_intf.bInterfaceNumber = status;
1483	ncm_union_desc.bSlaveInterface0 = status;
1484
1485	status = -ENODEV;
1486
1487	/* allocate instance-specific endpoints */
1488	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1489	if (!ep)
1490		goto fail;
1491	ncm->port.in_ep = ep;
1492
1493	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1494	if (!ep)
1495		goto fail;
1496	ncm->port.out_ep = ep;
1497
1498	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1499	if (!ep)
1500		goto fail;
1501	ncm->notify = ep;
1502
1503	status = -ENOMEM;
1504
1505	/* allocate notification request and buffer */
1506	ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1507	if (!ncm->notify_req)
1508		goto fail;
1509	ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1510	if (!ncm->notify_req->buf)
1511		goto fail;
1512	ncm->notify_req->context = ncm;
1513	ncm->notify_req->complete = ncm_notify_complete;
1514
1515	/*
1516	 * support all relevant hardware speeds... we expect that when
1517	 * hardware is dual speed, all bulk-capable endpoints work at
1518	 * both speeds
1519	 */
1520	hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1521	hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1522	hs_ncm_notify_desc.bEndpointAddress =
1523		fs_ncm_notify_desc.bEndpointAddress;
1524
1525	ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1526	ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1527	ss_ncm_notify_desc.bEndpointAddress =
1528		fs_ncm_notify_desc.bEndpointAddress;
1529
1530	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1531			ncm_ss_function, ncm_ss_function);
1532	if (status)
1533		goto fail;
1534
1535	/*
1536	 * NOTE:  all that is done without knowing or caring about
1537	 * the network link ... which is unavailable to this code
1538	 * until we're activated via set_alt().
1539	 */
1540
1541	ncm->port.open = ncm_open;
1542	ncm->port.close = ncm_close;
1543
1544	hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
1545	ncm->task_timer.function = ncm_tx_timeout;
1546
1547	DBG(cdev, "CDC Network: IN/%s OUT/%s NOTIFY/%s\n",
1548			ncm->port.in_ep->name, ncm->port.out_ep->name,
1549			ncm->notify->name);
1550	return 0;
1551
1552fail:
1553	kfree(f->os_desc_table);
1554	f->os_desc_n = 0;
1555
1556	if (ncm->notify_req) {
1557		kfree(ncm->notify_req->buf);
1558		usb_ep_free_request(ncm->notify, ncm->notify_req);
1559	}
1560
1561	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1562
1563	return status;
1564}
1565
1566static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1567{
1568	return container_of(to_config_group(item), struct f_ncm_opts,
1569			    func_inst.group);
1570}
1571
1572/* f_ncm_item_ops */
1573USB_ETHERNET_CONFIGFS_ITEM(ncm);
1574
1575/* f_ncm_opts_dev_addr */
1576USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1577
1578/* f_ncm_opts_host_addr */
1579USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1580
1581/* f_ncm_opts_qmult */
1582USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1583
1584/* f_ncm_opts_ifname */
1585USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1586
1587static struct configfs_attribute *ncm_attrs[] = {
1588	&ncm_opts_attr_dev_addr,
1589	&ncm_opts_attr_host_addr,
1590	&ncm_opts_attr_qmult,
1591	&ncm_opts_attr_ifname,
1592	NULL,
1593};
1594
1595static const struct config_item_type ncm_func_type = {
1596	.ct_item_ops	= &ncm_item_ops,
1597	.ct_attrs	= ncm_attrs,
1598	.ct_owner	= THIS_MODULE,
1599};
1600
1601static void ncm_free_inst(struct usb_function_instance *f)
1602{
1603	struct f_ncm_opts *opts;
1604
1605	opts = container_of(f, struct f_ncm_opts, func_inst);
1606	if (opts->bound)
1607		gether_cleanup(netdev_priv(opts->net));
1608	else
1609		free_netdev(opts->net);
1610	kfree(opts->ncm_interf_group);
1611	kfree(opts);
1612}
1613
1614static struct usb_function_instance *ncm_alloc_inst(void)
1615{
1616	struct f_ncm_opts *opts;
1617	struct usb_os_desc *descs[1];
1618	char *names[1];
1619	struct config_group *ncm_interf_group;
1620
1621	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1622	if (!opts)
1623		return ERR_PTR(-ENOMEM);
1624	opts->ncm_os_desc.ext_compat_id = opts->ncm_ext_compat_id;
1625
1626	mutex_init(&opts->lock);
1627	opts->func_inst.free_func_inst = ncm_free_inst;
1628	opts->net = gether_setup_default();
1629	if (IS_ERR(opts->net)) {
1630		struct net_device *net = opts->net;
1631		kfree(opts);
1632		return ERR_CAST(net);
1633	}
1634	INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
1635
1636	descs[0] = &opts->ncm_os_desc;
1637	names[0] = "ncm";
1638
1639	config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1640	ncm_interf_group =
1641		usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
1642					       names, THIS_MODULE);
1643	if (IS_ERR(ncm_interf_group)) {
1644		ncm_free_inst(&opts->func_inst);
1645		return ERR_CAST(ncm_interf_group);
1646	}
1647	opts->ncm_interf_group = ncm_interf_group;
1648
1649	return &opts->func_inst;
1650}
1651
1652static void ncm_free(struct usb_function *f)
1653{
1654	struct f_ncm *ncm;
1655	struct f_ncm_opts *opts;
1656
1657	ncm = func_to_ncm(f);
1658	opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1659	kfree(ncm);
1660	mutex_lock(&opts->lock);
1661	opts->refcnt--;
1662	mutex_unlock(&opts->lock);
1663}
1664
1665static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1666{
1667	struct f_ncm *ncm = func_to_ncm(f);
1668
1669	DBG(c->cdev, "ncm unbind\n");
1670
1671	hrtimer_cancel(&ncm->task_timer);
1672
1673	kfree(f->os_desc_table);
1674	f->os_desc_n = 0;
1675
1676	ncm_string_defs[0].id = 0;
1677	usb_free_all_descriptors(f);
1678
1679	if (atomic_read(&ncm->notify_count)) {
1680		usb_ep_dequeue(ncm->notify, ncm->notify_req);
1681		atomic_set(&ncm->notify_count, 0);
1682	}
1683
1684	kfree(ncm->notify_req->buf);
1685	usb_ep_free_request(ncm->notify, ncm->notify_req);
1686}
1687
1688static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1689{
1690	struct f_ncm		*ncm;
1691	struct f_ncm_opts	*opts;
1692	int status;
1693
1694	/* allocate and initialize one new instance */
1695	ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1696	if (!ncm)
1697		return ERR_PTR(-ENOMEM);
1698
1699	opts = container_of(fi, struct f_ncm_opts, func_inst);
1700	mutex_lock(&opts->lock);
1701	opts->refcnt++;
1702
1703	/* export host's Ethernet address in CDC format */
1704	status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1705				      sizeof(ncm->ethaddr));
1706	if (status < 12) { /* strlen("01234567890a") */
1707		kfree(ncm);
1708		mutex_unlock(&opts->lock);
1709		return ERR_PTR(-EINVAL);
1710	}
1711	ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1712
1713	spin_lock_init(&ncm->lock);
1714	ncm_reset_values(ncm);
1715	ncm->port.ioport = netdev_priv(opts->net);
1716	mutex_unlock(&opts->lock);
1717	ncm->port.is_fixed = true;
1718	ncm->port.supports_multi_frame = true;
1719
1720	ncm->port.func.name = "cdc_network";
1721	/* descriptors are per-instance copies */
1722	ncm->port.func.bind = ncm_bind;
1723	ncm->port.func.unbind = ncm_unbind;
1724	ncm->port.func.set_alt = ncm_set_alt;
1725	ncm->port.func.get_alt = ncm_get_alt;
1726	ncm->port.func.setup = ncm_setup;
1727	ncm->port.func.disable = ncm_disable;
1728	ncm->port.func.free_func = ncm_free;
1729
1730	ncm->port.wrap = ncm_wrap_ntb;
1731	ncm->port.unwrap = ncm_unwrap_ntb;
1732
1733	return &ncm->port.func;
1734}
1735
1736DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1737MODULE_LICENSE("GPL");
1738MODULE_AUTHOR("Yauheni Kaliuta");
1739