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/*
107 * Although max mtu as dictated by u_ether is 15412 bytes, setting
108 * max_segment_size to 15426 would not be efficient. If user chooses segment
109 * size to be (>= 8192), then we can't aggregate more than one buffer in each
110 * NTB (assuming each packet coming from network layer is >= 8192 bytes) as ep
111 * maxpacket limit is 16384. So let max_segment_size be limited to 8000 to allow
112 * at least 2 packets to be aggregated reducing wastage of NTB buffer space
113 */
114#define MAX_DATAGRAM_SIZE	8000
115
116#define FORMATS_SUPPORTED	(USB_CDC_NCM_NTB16_SUPPORTED |	\
117				 USB_CDC_NCM_NTB32_SUPPORTED)
118
119static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
120	.wLength = cpu_to_le16(sizeof(ntb_parameters)),
121	.bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
122	.dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
123	.wNdpInDivisor = cpu_to_le16(4),
124	.wNdpInPayloadRemainder = cpu_to_le16(0),
125	.wNdpInAlignment = cpu_to_le16(4),
126
127	.dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
128	.wNdpOutDivisor = cpu_to_le16(4),
129	.wNdpOutPayloadRemainder = cpu_to_le16(0),
130	.wNdpOutAlignment = cpu_to_le16(4),
131};
132
133/*
134 * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
135 * packet, to simplify cancellation; and a big transfer interval, to
136 * waste less bandwidth.
137 */
138
139#define NCM_STATUS_INTERVAL_MS		32
140#define NCM_STATUS_BYTECOUNT		16	/* 8 byte header + data */
141
142static struct usb_interface_assoc_descriptor ncm_iad_desc = {
143	.bLength =		sizeof ncm_iad_desc,
144	.bDescriptorType =	USB_DT_INTERFACE_ASSOCIATION,
145
146	/* .bFirstInterface =	DYNAMIC, */
147	.bInterfaceCount =	2,	/* control + data */
148	.bFunctionClass =	USB_CLASS_COMM,
149	.bFunctionSubClass =	USB_CDC_SUBCLASS_NCM,
150	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
151	/* .iFunction =		DYNAMIC */
152};
153
154/* interface descriptor: */
155
156static struct usb_interface_descriptor ncm_control_intf = {
157	.bLength =		sizeof ncm_control_intf,
158	.bDescriptorType =	USB_DT_INTERFACE,
159
160	/* .bInterfaceNumber = DYNAMIC */
161	.bNumEndpoints =	1,
162	.bInterfaceClass =	USB_CLASS_COMM,
163	.bInterfaceSubClass =	USB_CDC_SUBCLASS_NCM,
164	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
165	/* .iInterface = DYNAMIC */
166};
167
168static struct usb_cdc_header_desc ncm_header_desc = {
169	.bLength =		sizeof ncm_header_desc,
170	.bDescriptorType =	USB_DT_CS_INTERFACE,
171	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
172
173	.bcdCDC =		cpu_to_le16(0x0110),
174};
175
176static struct usb_cdc_union_desc ncm_union_desc = {
177	.bLength =		sizeof(ncm_union_desc),
178	.bDescriptorType =	USB_DT_CS_INTERFACE,
179	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
180	/* .bMasterInterface0 =	DYNAMIC */
181	/* .bSlaveInterface0 =	DYNAMIC */
182};
183
184static struct usb_cdc_ether_desc ecm_desc = {
185	.bLength =		sizeof ecm_desc,
186	.bDescriptorType =	USB_DT_CS_INTERFACE,
187	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
188
189	/* this descriptor actually adds value, surprise! */
190	/* .iMACAddress = DYNAMIC */
191	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
192	.wNumberMCFilters =	cpu_to_le16(0),
193	.bNumberPowerFilters =	0,
194};
195
196#define NCAPS	(USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
197
198static struct usb_cdc_ncm_desc ncm_desc = {
199	.bLength =		sizeof ncm_desc,
200	.bDescriptorType =	USB_DT_CS_INTERFACE,
201	.bDescriptorSubType =	USB_CDC_NCM_TYPE,
202
203	.bcdNcmVersion =	cpu_to_le16(0x0100),
204	/* can process SetEthernetPacketFilter */
205	.bmNetworkCapabilities = NCAPS,
206};
207
208/* the default data interface has no endpoints ... */
209
210static struct usb_interface_descriptor ncm_data_nop_intf = {
211	.bLength =		sizeof ncm_data_nop_intf,
212	.bDescriptorType =	USB_DT_INTERFACE,
213
214	.bInterfaceNumber =	1,
215	.bAlternateSetting =	0,
216	.bNumEndpoints =	0,
217	.bInterfaceClass =	USB_CLASS_CDC_DATA,
218	.bInterfaceSubClass =	0,
219	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
220	/* .iInterface = DYNAMIC */
221};
222
223/* ... but the "real" data interface has two bulk endpoints */
224
225static struct usb_interface_descriptor ncm_data_intf = {
226	.bLength =		sizeof ncm_data_intf,
227	.bDescriptorType =	USB_DT_INTERFACE,
228
229	.bInterfaceNumber =	1,
230	.bAlternateSetting =	1,
231	.bNumEndpoints =	2,
232	.bInterfaceClass =	USB_CLASS_CDC_DATA,
233	.bInterfaceSubClass =	0,
234	.bInterfaceProtocol =	USB_CDC_NCM_PROTO_NTB,
235	/* .iInterface = DYNAMIC */
236};
237
238/* full speed support: */
239
240static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
241	.bLength =		USB_DT_ENDPOINT_SIZE,
242	.bDescriptorType =	USB_DT_ENDPOINT,
243
244	.bEndpointAddress =	USB_DIR_IN,
245	.bmAttributes =		USB_ENDPOINT_XFER_INT,
246	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
247	.bInterval =		NCM_STATUS_INTERVAL_MS,
248};
249
250static struct usb_endpoint_descriptor fs_ncm_in_desc = {
251	.bLength =		USB_DT_ENDPOINT_SIZE,
252	.bDescriptorType =	USB_DT_ENDPOINT,
253
254	.bEndpointAddress =	USB_DIR_IN,
255	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
256};
257
258static struct usb_endpoint_descriptor fs_ncm_out_desc = {
259	.bLength =		USB_DT_ENDPOINT_SIZE,
260	.bDescriptorType =	USB_DT_ENDPOINT,
261
262	.bEndpointAddress =	USB_DIR_OUT,
263	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
264};
265
266static struct usb_descriptor_header *ncm_fs_function[] = {
267	(struct usb_descriptor_header *) &ncm_iad_desc,
268	/* CDC NCM control descriptors */
269	(struct usb_descriptor_header *) &ncm_control_intf,
270	(struct usb_descriptor_header *) &ncm_header_desc,
271	(struct usb_descriptor_header *) &ncm_union_desc,
272	(struct usb_descriptor_header *) &ecm_desc,
273	(struct usb_descriptor_header *) &ncm_desc,
274	(struct usb_descriptor_header *) &fs_ncm_notify_desc,
275	/* data interface, altsettings 0 and 1 */
276	(struct usb_descriptor_header *) &ncm_data_nop_intf,
277	(struct usb_descriptor_header *) &ncm_data_intf,
278	(struct usb_descriptor_header *) &fs_ncm_in_desc,
279	(struct usb_descriptor_header *) &fs_ncm_out_desc,
280	NULL,
281};
282
283/* high speed support: */
284
285static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
286	.bLength =		USB_DT_ENDPOINT_SIZE,
287	.bDescriptorType =	USB_DT_ENDPOINT,
288
289	.bEndpointAddress =	USB_DIR_IN,
290	.bmAttributes =		USB_ENDPOINT_XFER_INT,
291	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
292	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
293};
294static struct usb_endpoint_descriptor hs_ncm_in_desc = {
295	.bLength =		USB_DT_ENDPOINT_SIZE,
296	.bDescriptorType =	USB_DT_ENDPOINT,
297
298	.bEndpointAddress =	USB_DIR_IN,
299	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
300	.wMaxPacketSize =	cpu_to_le16(512),
301};
302
303static struct usb_endpoint_descriptor hs_ncm_out_desc = {
304	.bLength =		USB_DT_ENDPOINT_SIZE,
305	.bDescriptorType =	USB_DT_ENDPOINT,
306
307	.bEndpointAddress =	USB_DIR_OUT,
308	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
309	.wMaxPacketSize =	cpu_to_le16(512),
310};
311
312static struct usb_descriptor_header *ncm_hs_function[] = {
313	(struct usb_descriptor_header *) &ncm_iad_desc,
314	/* CDC NCM control descriptors */
315	(struct usb_descriptor_header *) &ncm_control_intf,
316	(struct usb_descriptor_header *) &ncm_header_desc,
317	(struct usb_descriptor_header *) &ncm_union_desc,
318	(struct usb_descriptor_header *) &ecm_desc,
319	(struct usb_descriptor_header *) &ncm_desc,
320	(struct usb_descriptor_header *) &hs_ncm_notify_desc,
321	/* data interface, altsettings 0 and 1 */
322	(struct usb_descriptor_header *) &ncm_data_nop_intf,
323	(struct usb_descriptor_header *) &ncm_data_intf,
324	(struct usb_descriptor_header *) &hs_ncm_in_desc,
325	(struct usb_descriptor_header *) &hs_ncm_out_desc,
326	NULL,
327};
328
329
330/* super speed support: */
331
332static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
333	.bLength =		USB_DT_ENDPOINT_SIZE,
334	.bDescriptorType =	USB_DT_ENDPOINT,
335
336	.bEndpointAddress =	USB_DIR_IN,
337	.bmAttributes =		USB_ENDPOINT_XFER_INT,
338	.wMaxPacketSize =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
339	.bInterval =		USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
340};
341
342static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
343	.bLength =		sizeof(ss_ncm_notify_comp_desc),
344	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
345
346	/* the following 3 values can be tweaked if necessary */
347	/* .bMaxBurst =		0, */
348	/* .bmAttributes =	0, */
349	.wBytesPerInterval =	cpu_to_le16(NCM_STATUS_BYTECOUNT),
350};
351
352static struct usb_endpoint_descriptor ss_ncm_in_desc = {
353	.bLength =		USB_DT_ENDPOINT_SIZE,
354	.bDescriptorType =	USB_DT_ENDPOINT,
355
356	.bEndpointAddress =	USB_DIR_IN,
357	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
358	.wMaxPacketSize =	cpu_to_le16(1024),
359};
360
361static struct usb_endpoint_descriptor ss_ncm_out_desc = {
362	.bLength =		USB_DT_ENDPOINT_SIZE,
363	.bDescriptorType =	USB_DT_ENDPOINT,
364
365	.bEndpointAddress =	USB_DIR_OUT,
366	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
367	.wMaxPacketSize =	cpu_to_le16(1024),
368};
369
370static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
371	.bLength =		sizeof(ss_ncm_bulk_comp_desc),
372	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
373
374	/* the following 2 values can be tweaked if necessary */
375	.bMaxBurst =		15,
376	/* .bmAttributes =	0, */
377};
378
379static struct usb_descriptor_header *ncm_ss_function[] = {
380	(struct usb_descriptor_header *) &ncm_iad_desc,
381	/* CDC NCM control descriptors */
382	(struct usb_descriptor_header *) &ncm_control_intf,
383	(struct usb_descriptor_header *) &ncm_header_desc,
384	(struct usb_descriptor_header *) &ncm_union_desc,
385	(struct usb_descriptor_header *) &ecm_desc,
386	(struct usb_descriptor_header *) &ncm_desc,
387	(struct usb_descriptor_header *) &ss_ncm_notify_desc,
388	(struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
389	/* data interface, altsettings 0 and 1 */
390	(struct usb_descriptor_header *) &ncm_data_nop_intf,
391	(struct usb_descriptor_header *) &ncm_data_intf,
392	(struct usb_descriptor_header *) &ss_ncm_in_desc,
393	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
394	(struct usb_descriptor_header *) &ss_ncm_out_desc,
395	(struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
396	NULL,
397};
398
399/* string descriptors: */
400
401#define STRING_CTRL_IDX	0
402#define STRING_MAC_IDX	1
403#define STRING_DATA_IDX	2
404#define STRING_IAD_IDX	3
405
406static struct usb_string ncm_string_defs[] = {
407	[STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
408	[STRING_MAC_IDX].s = "",
409	[STRING_DATA_IDX].s = "CDC Network Data",
410	[STRING_IAD_IDX].s = "CDC NCM",
411	{  } /* end of list */
412};
413
414static struct usb_gadget_strings ncm_string_table = {
415	.language =		0x0409,	/* en-us */
416	.strings =		ncm_string_defs,
417};
418
419static struct usb_gadget_strings *ncm_strings[] = {
420	&ncm_string_table,
421	NULL,
422};
423
424/*
425 * Here are options for NCM Datagram Pointer table (NDP) parser.
426 * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
427 * in NDP16 offsets and sizes fields are 1 16bit word wide,
428 * in NDP32 -- 2 16bit words wide. Also signatures are different.
429 * To make the parser code the same, put the differences in the structure,
430 * and switch pointers to the structures when the format is changed.
431 */
432
433struct ndp_parser_opts {
434	u32		nth_sign;
435	u32		ndp_sign;
436	unsigned	nth_size;
437	unsigned	ndp_size;
438	unsigned	dpe_size;
439	unsigned	ndplen_align;
440	/* sizes in u16 units */
441	unsigned	dgram_item_len; /* index or length */
442	unsigned	block_length;
443	unsigned	ndp_index;
444	unsigned	reserved1;
445	unsigned	reserved2;
446	unsigned	next_ndp_index;
447};
448
449static const struct ndp_parser_opts ndp16_opts = {
450	.nth_sign = USB_CDC_NCM_NTH16_SIGN,
451	.ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,
452	.nth_size = sizeof(struct usb_cdc_ncm_nth16),
453	.ndp_size = sizeof(struct usb_cdc_ncm_ndp16),
454	.dpe_size = sizeof(struct usb_cdc_ncm_dpe16),
455	.ndplen_align = 4,
456	.dgram_item_len = 1,
457	.block_length = 1,
458	.ndp_index = 1,
459	.reserved1 = 0,
460	.reserved2 = 0,
461	.next_ndp_index = 1,
462};
463
464static const struct ndp_parser_opts ndp32_opts = {
465	.nth_sign = USB_CDC_NCM_NTH32_SIGN,
466	.ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,
467	.nth_size = sizeof(struct usb_cdc_ncm_nth32),
468	.ndp_size = sizeof(struct usb_cdc_ncm_ndp32),
469	.dpe_size = sizeof(struct usb_cdc_ncm_dpe32),
470	.ndplen_align = 8,
471	.dgram_item_len = 2,
472	.block_length = 2,
473	.ndp_index = 2,
474	.reserved1 = 1,
475	.reserved2 = 2,
476	.next_ndp_index = 2,
477};
478
479static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
480{
481	switch (size) {
482	case 1:
483		put_unaligned_le16((u16)val, *p);
484		break;
485	case 2:
486		put_unaligned_le32((u32)val, *p);
487
488		break;
489	default:
490		BUG();
491	}
492
493	*p += size;
494}
495
496static inline unsigned get_ncm(__le16 **p, unsigned size)
497{
498	unsigned tmp;
499
500	switch (size) {
501	case 1:
502		tmp = get_unaligned_le16(*p);
503		break;
504	case 2:
505		tmp = get_unaligned_le32(*p);
506		break;
507	default:
508		BUG();
509	}
510
511	*p += size;
512	return tmp;
513}
514
515/*-------------------------------------------------------------------------*/
516
517static inline void ncm_reset_values(struct f_ncm *ncm)
518{
519	ncm->parser_opts = &ndp16_opts;
520	ncm->is_crc = false;
521	ncm->ndp_sign = ncm->parser_opts->ndp_sign;
522	ncm->port.cdc_filter = DEFAULT_FILTER;
523
524	/* doesn't make sense for ncm, fixed size used */
525	ncm->port.header_len = 0;
526
527	ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
528	ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
529}
530
531/*
532 * Context: ncm->lock held
533 */
534static void ncm_do_notify(struct f_ncm *ncm)
535{
536	struct usb_request		*req = ncm->notify_req;
537	struct usb_cdc_notification	*event;
538	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
539	__le32				*data;
540	int				status;
541
542	/* notification already in flight? */
543	if (atomic_read(&ncm->notify_count))
544		return;
545
546	event = req->buf;
547	switch (ncm->notify_state) {
548	case NCM_NOTIFY_NONE:
549		return;
550
551	case NCM_NOTIFY_CONNECT:
552		event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
553		if (ncm->is_open)
554			event->wValue = cpu_to_le16(1);
555		else
556			event->wValue = cpu_to_le16(0);
557		event->wLength = 0;
558		req->length = sizeof *event;
559
560		DBG(cdev, "notify connect %s\n",
561				ncm->is_open ? "true" : "false");
562		ncm->notify_state = NCM_NOTIFY_NONE;
563		break;
564
565	case NCM_NOTIFY_SPEED:
566		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
567		event->wValue = cpu_to_le16(0);
568		event->wLength = cpu_to_le16(8);
569		req->length = NCM_STATUS_BYTECOUNT;
570
571		/* SPEED_CHANGE data is up/down speeds in bits/sec */
572		data = req->buf + sizeof *event;
573		data[0] = cpu_to_le32(gether_bitrate(cdev->gadget));
574		data[1] = data[0];
575
576		DBG(cdev, "notify speed %u\n", gether_bitrate(cdev->gadget));
577		ncm->notify_state = NCM_NOTIFY_CONNECT;
578		break;
579	}
580	event->bmRequestType = 0xA1;
581	event->wIndex = cpu_to_le16(ncm->ctrl_id);
582
583	atomic_inc(&ncm->notify_count);
584
585	/*
586	 * In double buffering if there is a space in FIFO,
587	 * completion callback can be called right after the call,
588	 * so unlocking
589	 */
590	spin_unlock(&ncm->lock);
591	status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
592	spin_lock(&ncm->lock);
593	if (status < 0) {
594		atomic_dec(&ncm->notify_count);
595		DBG(cdev, "notify --> %d\n", status);
596	}
597}
598
599/*
600 * Context: ncm->lock held
601 */
602static void ncm_notify(struct f_ncm *ncm)
603{
604	/*
605	 * NOTE on most versions of Linux, host side cdc-ethernet
606	 * won't listen for notifications until its netdevice opens.
607	 * The first notification then sits in the FIFO for a long
608	 * time, and the second one is queued.
609	 *
610	 * If ncm_notify() is called before the second (CONNECT)
611	 * notification is sent, then it will reset to send the SPEED
612	 * notificaion again (and again, and again), but it's not a problem
613	 */
614	ncm->notify_state = NCM_NOTIFY_SPEED;
615	ncm_do_notify(ncm);
616}
617
618static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
619{
620	struct f_ncm			*ncm = req->context;
621	struct usb_composite_dev	*cdev = ncm->port.func.config->cdev;
622	struct usb_cdc_notification	*event = req->buf;
623
624	spin_lock(&ncm->lock);
625	switch (req->status) {
626	case 0:
627		VDBG(cdev, "Notification %02x sent\n",
628		     event->bNotificationType);
629		atomic_dec(&ncm->notify_count);
630		break;
631	case -ECONNRESET:
632	case -ESHUTDOWN:
633		atomic_set(&ncm->notify_count, 0);
634		ncm->notify_state = NCM_NOTIFY_NONE;
635		break;
636	default:
637		DBG(cdev, "event %02x --> %d\n",
638			event->bNotificationType, req->status);
639		atomic_dec(&ncm->notify_count);
640		break;
641	}
642	ncm_do_notify(ncm);
643	spin_unlock(&ncm->lock);
644}
645
646static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
647{
648	/* now for SET_NTB_INPUT_SIZE only */
649	unsigned		in_size;
650	struct usb_function	*f = req->context;
651	struct f_ncm		*ncm = func_to_ncm(f);
652	struct usb_composite_dev *cdev = f->config->cdev;
653
654	req->context = NULL;
655	if (req->status || req->actual != req->length) {
656		DBG(cdev, "Bad control-OUT transfer\n");
657		goto invalid;
658	}
659
660	in_size = get_unaligned_le32(req->buf);
661	if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
662	    in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
663		DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
664		goto invalid;
665	}
666
667	ncm->port.fixed_in_len = in_size;
668	VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
669	return;
670
671invalid:
672	usb_ep_set_halt(ep);
673	return;
674}
675
676static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
677{
678	struct f_ncm		*ncm = func_to_ncm(f);
679	struct usb_composite_dev *cdev = f->config->cdev;
680	struct usb_request	*req = cdev->req;
681	int			value = -EOPNOTSUPP;
682	u16			w_index = le16_to_cpu(ctrl->wIndex);
683	u16			w_value = le16_to_cpu(ctrl->wValue);
684	u16			w_length = le16_to_cpu(ctrl->wLength);
685
686	/*
687	 * composite driver infrastructure handles everything except
688	 * CDC class messages; interface activation uses set_alt().
689	 */
690	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
691	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
692			| USB_CDC_SET_ETHERNET_PACKET_FILTER:
693		/*
694		 * see 6.2.30: no data, wIndex = interface,
695		 * wValue = packet filter bitmap
696		 */
697		if (w_length != 0 || w_index != ncm->ctrl_id)
698			goto invalid;
699		DBG(cdev, "packet filter %02x\n", w_value);
700		/*
701		 * REVISIT locking of cdc_filter.  This assumes the UDC
702		 * driver won't have a concurrent packet TX irq running on
703		 * another CPU; or that if it does, this write is atomic...
704		 */
705		ncm->port.cdc_filter = w_value;
706		value = 0;
707		break;
708	/*
709	 * and optionally:
710	 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
711	 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
712	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
713	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
714	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
715	 * case USB_CDC_GET_ETHERNET_STATISTIC:
716	 */
717
718	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
719		| USB_CDC_GET_NTB_PARAMETERS:
720
721		if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
722			goto invalid;
723		value = w_length > sizeof ntb_parameters ?
724			sizeof ntb_parameters : w_length;
725		memcpy(req->buf, &ntb_parameters, value);
726		VDBG(cdev, "Host asked NTB parameters\n");
727		break;
728
729	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
730		| USB_CDC_GET_NTB_INPUT_SIZE:
731
732		if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
733			goto invalid;
734		put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
735		value = 4;
736		VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
737		     ncm->port.fixed_in_len);
738		break;
739
740	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
741		| USB_CDC_SET_NTB_INPUT_SIZE:
742	{
743		if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
744			goto invalid;
745		req->complete = ncm_ep0out_complete;
746		req->length = w_length;
747		req->context = f;
748
749		value = req->length;
750		break;
751	}
752
753	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
754		| USB_CDC_GET_NTB_FORMAT:
755	{
756		uint16_t format;
757
758		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
759			goto invalid;
760		format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
761		put_unaligned_le16(format, req->buf);
762		value = 2;
763		VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
764		break;
765	}
766
767	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
768		| USB_CDC_SET_NTB_FORMAT:
769	{
770		if (w_length != 0 || w_index != ncm->ctrl_id)
771			goto invalid;
772		switch (w_value) {
773		case 0x0000:
774			ncm->parser_opts = &ndp16_opts;
775			DBG(cdev, "NCM16 selected\n");
776			break;
777		case 0x0001:
778			ncm->parser_opts = &ndp32_opts;
779			DBG(cdev, "NCM32 selected\n");
780			break;
781		default:
782			goto invalid;
783		}
784		value = 0;
785		break;
786	}
787	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
788		| USB_CDC_GET_CRC_MODE:
789	{
790		uint16_t is_crc;
791
792		if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
793			goto invalid;
794		is_crc = ncm->is_crc ? 0x0001 : 0x0000;
795		put_unaligned_le16(is_crc, req->buf);
796		value = 2;
797		VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
798		break;
799	}
800
801	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
802		| USB_CDC_SET_CRC_MODE:
803	{
804		if (w_length != 0 || w_index != ncm->ctrl_id)
805			goto invalid;
806		switch (w_value) {
807		case 0x0000:
808			ncm->is_crc = false;
809			DBG(cdev, "non-CRC mode selected\n");
810			break;
811		case 0x0001:
812			ncm->is_crc = true;
813			DBG(cdev, "CRC mode selected\n");
814			break;
815		default:
816			goto invalid;
817		}
818		value = 0;
819		break;
820	}
821
822	/* and disabled in ncm descriptor: */
823	/* case USB_CDC_GET_NET_ADDRESS: */
824	/* case USB_CDC_SET_NET_ADDRESS: */
825	/* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
826	/* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
827
828	default:
829invalid:
830		DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
831			ctrl->bRequestType, ctrl->bRequest,
832			w_value, w_index, w_length);
833	}
834	ncm->ndp_sign = ncm->parser_opts->ndp_sign |
835		(ncm->is_crc ? NCM_NDP_HDR_CRC : 0);
836
837	/* respond with data transfer or status phase? */
838	if (value >= 0) {
839		DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
840			ctrl->bRequestType, ctrl->bRequest,
841			w_value, w_index, w_length);
842		req->zero = 0;
843		req->length = value;
844		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
845		if (value < 0)
846			ERROR(cdev, "ncm req %02x.%02x response err %d\n",
847					ctrl->bRequestType, ctrl->bRequest,
848					value);
849	}
850
851	/* device either stalls (value < 0) or reports success */
852	return value;
853}
854
855
856static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
857{
858	struct f_ncm		*ncm = func_to_ncm(f);
859	struct usb_composite_dev *cdev = f->config->cdev;
860
861	/* Control interface has only altsetting 0 */
862	if (intf == ncm->ctrl_id) {
863		if (alt != 0)
864			goto fail;
865
866		DBG(cdev, "reset ncm control %d\n", intf);
867		usb_ep_disable(ncm->notify);
868
869		if (!(ncm->notify->desc)) {
870			DBG(cdev, "init ncm ctrl %d\n", intf);
871			if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
872				goto fail;
873		}
874		usb_ep_enable(ncm->notify);
875
876	/* Data interface has two altsettings, 0 and 1 */
877	} else if (intf == ncm->data_id) {
878		if (alt > 1)
879			goto fail;
880
881		if (ncm->netdev) {
882			DBG(cdev, "reset ncm\n");
883			ncm->netdev = NULL;
884			gether_disconnect(&ncm->port);
885			ncm_reset_values(ncm);
886		}
887
888		/*
889		 * CDC Network only sends data in non-default altsettings.
890		 * Changing altsettings resets filters, statistics, etc.
891		 */
892		if (alt == 1) {
893			struct net_device	*net;
894
895			if (!ncm->port.in_ep->desc ||
896			    !ncm->port.out_ep->desc) {
897				DBG(cdev, "init ncm\n");
898				if (config_ep_by_speed(cdev->gadget, f,
899						       ncm->port.in_ep) ||
900				    config_ep_by_speed(cdev->gadget, f,
901						       ncm->port.out_ep)) {
902					ncm->port.in_ep->desc = NULL;
903					ncm->port.out_ep->desc = NULL;
904					goto fail;
905				}
906			}
907
908			/* TODO */
909			/* Enable zlps by default for NCM conformance;
910			 * override for musb_hdrc (avoids txdma ovhead)
911			 */
912			ncm->port.is_zlp_ok =
913				gadget_is_zlp_supported(cdev->gadget);
914			ncm->port.cdc_filter = DEFAULT_FILTER;
915			DBG(cdev, "activate ncm\n");
916			net = gether_connect(&ncm->port);
917			if (IS_ERR(net))
918				return PTR_ERR(net);
919			ncm->netdev = net;
920		}
921
922		spin_lock(&ncm->lock);
923		ncm_notify(ncm);
924		spin_unlock(&ncm->lock);
925	} else
926		goto fail;
927
928	return 0;
929fail:
930	return -EINVAL;
931}
932
933/*
934 * Because the data interface supports multiple altsettings,
935 * this NCM function *MUST* implement a get_alt() method.
936 */
937static int ncm_get_alt(struct usb_function *f, unsigned intf)
938{
939	struct f_ncm		*ncm = func_to_ncm(f);
940
941	if (intf == ncm->ctrl_id)
942		return 0;
943	return ncm->port.in_ep->enabled ? 1 : 0;
944}
945
946static struct sk_buff *package_for_tx(struct f_ncm *ncm)
947{
948	__le16		*ntb_iter;
949	struct sk_buff	*skb2 = NULL;
950	unsigned	ndp_pad;
951	unsigned	ndp_index;
952	unsigned	new_len;
953
954	const struct ndp_parser_opts *opts = ncm->parser_opts;
955	const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
956	const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
957
958	/* Stop the timer */
959	hrtimer_try_to_cancel(&ncm->task_timer);
960
961	ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
962			ncm->skb_tx_data->len;
963	ndp_index = ncm->skb_tx_data->len + ndp_pad;
964	new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
965
966	/* Set the final BlockLength and wNdpIndex */
967	ntb_iter = (void *) ncm->skb_tx_data->data;
968	/* Increment pointer to BlockLength */
969	ntb_iter += 2 + 1 + 1;
970	put_ncm(&ntb_iter, opts->block_length, new_len);
971	put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
972
973	/* Set the final NDP wLength */
974	new_len = opts->ndp_size +
975			(ncm->ndp_dgram_count * dgram_idx_len);
976	ncm->ndp_dgram_count = 0;
977	/* Increment from start to wLength */
978	ntb_iter = (void *) ncm->skb_tx_ndp->data;
979	ntb_iter += 2;
980	put_unaligned_le16(new_len, ntb_iter);
981
982	/* Merge the skbs */
983	swap(skb2, ncm->skb_tx_data);
984	if (ncm->skb_tx_data) {
985		dev_consume_skb_any(ncm->skb_tx_data);
986		ncm->skb_tx_data = NULL;
987	}
988
989	/* Insert NDP alignment. */
990	skb_put_zero(skb2, ndp_pad);
991
992	/* Copy NTB across. */
993	skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
994	dev_consume_skb_any(ncm->skb_tx_ndp);
995	ncm->skb_tx_ndp = NULL;
996
997	/* Insert zero'd datagram. */
998	skb_put_zero(skb2, dgram_idx_len);
999
1000	return skb2;
1001}
1002
1003static struct sk_buff *ncm_wrap_ntb(struct gether *port,
1004				    struct sk_buff *skb)
1005{
1006	struct f_ncm	*ncm = func_to_ncm(&port->func);
1007	struct sk_buff	*skb2 = NULL;
1008
1009	if (skb) {
1010		int		ncb_len = 0;
1011		__le16		*ntb_data;
1012		__le16		*ntb_ndp;
1013		int		dgram_pad;
1014
1015		unsigned	max_size = ncm->port.fixed_in_len;
1016		const struct ndp_parser_opts *opts = ncm->parser_opts;
1017		const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1018		const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1019		const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1020		const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1021
1022		/* Add the CRC if required up front */
1023		if (ncm->is_crc) {
1024			uint32_t	crc;
1025			__le16		*crc_pos;
1026
1027			crc = ~crc32_le(~0,
1028					skb->data,
1029					skb->len);
1030			crc_pos = skb_put(skb, sizeof(uint32_t));
1031			put_unaligned_le32(crc, crc_pos);
1032		}
1033
1034		/* If the new skb is too big for the current NCM NTB then
1035		 * set the current stored skb to be sent now and clear it
1036		 * ready for new data.
1037		 * NOTE: Assume maximum align for speed of calculation.
1038		 */
1039		if (ncm->skb_tx_data
1040		    && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1041		    || (ncm->skb_tx_data->len +
1042		    div + rem + skb->len +
1043		    ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1044		    > max_size)) {
1045			skb2 = package_for_tx(ncm);
1046			if (!skb2)
1047				goto err;
1048		}
1049
1050		if (!ncm->skb_tx_data) {
1051			ncb_len = opts->nth_size;
1052			dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1053			ncb_len += dgram_pad;
1054
1055			/* Create a new skb for the NTH and datagrams. */
1056			ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1057			if (!ncm->skb_tx_data)
1058				goto err;
1059
1060			ncm->skb_tx_data->dev = ncm->netdev;
1061			ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1062			/* dwSignature */
1063			put_unaligned_le32(opts->nth_sign, ntb_data);
1064			ntb_data += 2;
1065			/* wHeaderLength */
1066			put_unaligned_le16(opts->nth_size, ntb_data++);
1067
1068			/* Allocate an skb for storing the NDP,
1069			 * TX_MAX_NUM_DPE should easily suffice for a
1070			 * 16k packet.
1071			 */
1072			ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1073						    + opts->dpe_size
1074						    * TX_MAX_NUM_DPE),
1075						    GFP_ATOMIC);
1076			if (!ncm->skb_tx_ndp)
1077				goto err;
1078
1079			ncm->skb_tx_ndp->dev = ncm->netdev;
1080			ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1081			memset(ntb_ndp, 0, ncb_len);
1082			/* dwSignature */
1083			put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1084			ntb_ndp += 2;
1085
1086			/* There is always a zeroed entry */
1087			ncm->ndp_dgram_count = 1;
1088
1089			/* Note: we skip opts->next_ndp_index */
1090
1091			/* Start the timer. */
1092			hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1093				      HRTIMER_MODE_REL_SOFT);
1094		}
1095
1096		/* Add the datagram position entries */
1097		ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1098
1099		ncb_len = ncm->skb_tx_data->len;
1100		dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1101		ncb_len += dgram_pad;
1102
1103		/* (d)wDatagramIndex */
1104		put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1105		/* (d)wDatagramLength */
1106		put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1107		ncm->ndp_dgram_count++;
1108
1109		/* Add the new data to the skb */
1110		skb_put_zero(ncm->skb_tx_data, dgram_pad);
1111		skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1112		dev_consume_skb_any(skb);
1113		skb = NULL;
1114
1115	} else if (ncm->skb_tx_data) {
1116		/* If we get here ncm_wrap_ntb() was called with NULL skb,
1117		 * because eth_start_xmit() was called with NULL skb by
1118		 * ncm_tx_timeout() - hence, this is our signal to flush/send.
1119		 */
1120		skb2 = package_for_tx(ncm);
1121		if (!skb2)
1122			goto err;
1123	}
1124
1125	return skb2;
1126
1127err:
1128	ncm->netdev->stats.tx_dropped++;
1129
1130	if (skb)
1131		dev_kfree_skb_any(skb);
1132	if (ncm->skb_tx_data)
1133		dev_kfree_skb_any(ncm->skb_tx_data);
1134	if (ncm->skb_tx_ndp)
1135		dev_kfree_skb_any(ncm->skb_tx_ndp);
1136
1137	return NULL;
1138}
1139
1140/*
1141 * The transmit should only be run if no skb data has been sent
1142 * for a certain duration.
1143 */
1144static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1145{
1146	struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1147	struct net_device *netdev = READ_ONCE(ncm->netdev);
1148
1149	if (netdev) {
1150		/* XXX This allowance of a NULL skb argument to ndo_start_xmit
1151		 * XXX is not sane.  The gadget layer should be redesigned so
1152		 * XXX that the dev->wrap() invocations to build SKBs is transparent
1153		 * XXX and performed in some way outside of the ndo_start_xmit
1154		 * XXX interface.
1155		 *
1156		 * This will call directly into u_ether's eth_start_xmit()
1157		 */
1158		netdev->netdev_ops->ndo_start_xmit(NULL, netdev);
1159	}
1160	return HRTIMER_NORESTART;
1161}
1162
1163static int ncm_unwrap_ntb(struct gether *port,
1164			  struct sk_buff *skb,
1165			  struct sk_buff_head *list)
1166{
1167	struct f_ncm	*ncm = func_to_ncm(&port->func);
1168	unsigned char	*ntb_ptr = skb->data;
1169	__le16		*tmp;
1170	unsigned	index, index2;
1171	int		ndp_index;
1172	unsigned	dg_len, dg_len2;
1173	unsigned	ndp_len;
1174	unsigned	block_len;
1175	struct sk_buff	*skb2;
1176	int		ret = -EINVAL;
1177	unsigned	ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1178	unsigned	frame_max;
1179	const struct ndp_parser_opts *opts = ncm->parser_opts;
1180	unsigned	crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1181	int		dgram_counter;
1182	int		to_process = skb->len;
1183	struct f_ncm_opts *ncm_opts;
1184
1185	ncm_opts = container_of(port->func.fi, struct f_ncm_opts, func_inst);
1186	frame_max = ncm_opts->max_segment_size;
1187
1188parse_ntb:
1189	tmp = (__le16 *)ntb_ptr;
1190
1191	/* dwSignature */
1192	if (get_unaligned_le32(tmp) != opts->nth_sign) {
1193		INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1194			skb->len);
1195		print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1196			       skb->data, 32, false);
1197
1198		goto err;
1199	}
1200	tmp += 2;
1201	/* wHeaderLength */
1202	if (get_unaligned_le16(tmp++) != opts->nth_size) {
1203		INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1204		goto err;
1205	}
1206	tmp++; /* skip wSequence */
1207
1208	block_len = get_ncm(&tmp, opts->block_length);
1209	/* (d)wBlockLength */
1210	if (block_len > ntb_max) {
1211		INFO(port->func.config->cdev, "OUT size exceeded\n");
1212		goto err;
1213	}
1214
1215	ndp_index = get_ncm(&tmp, opts->ndp_index);
1216
1217	/* Run through all the NDP's in the NTB */
1218	do {
1219		/*
1220		 * NCM 3.2
1221		 * dwNdpIndex
1222		 */
1223		if (((ndp_index % 4) != 0) ||
1224				(ndp_index < opts->nth_size) ||
1225				(ndp_index > (block_len -
1226					      opts->ndp_size))) {
1227			INFO(port->func.config->cdev, "Bad index: %#X\n",
1228			     ndp_index);
1229			goto err;
1230		}
1231
1232		/*
1233		 * walk through NDP
1234		 * dwSignature
1235		 */
1236		tmp = (__le16 *)(ntb_ptr + ndp_index);
1237		if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1238			INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1239			goto err;
1240		}
1241		tmp += 2;
1242
1243		ndp_len = get_unaligned_le16(tmp++);
1244		/*
1245		 * NCM 3.3.1
1246		 * wLength
1247		 * entry is 2 items
1248		 * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1249		 * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1250		 * Each entry is a dgram index and a dgram length.
1251		 */
1252		if ((ndp_len < opts->ndp_size
1253				+ 2 * 2 * (opts->dgram_item_len * 2)) ||
1254				(ndp_len % opts->ndplen_align != 0)) {
1255			INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1256			     ndp_len);
1257			goto err;
1258		}
1259		tmp += opts->reserved1;
1260		/* Check for another NDP (d)wNextNdpIndex */
1261		ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1262		tmp += opts->reserved2;
1263
1264		ndp_len -= opts->ndp_size;
1265		index2 = get_ncm(&tmp, opts->dgram_item_len);
1266		dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1267		dgram_counter = 0;
1268
1269		do {
1270			index = index2;
1271			/* wDatagramIndex[0] */
1272			if ((index < opts->nth_size) ||
1273					(index > block_len - opts->dpe_size)) {
1274				INFO(port->func.config->cdev,
1275				     "Bad index: %#X\n", index);
1276				goto err;
1277			}
1278
1279			dg_len = dg_len2;
1280			/*
1281			 * wDatagramLength[0]
1282			 * ethernet hdr + crc or larger than max frame size
1283			 */
1284			if ((dg_len < 14 + crc_len) ||
1285					(dg_len > frame_max)) {
1286				INFO(port->func.config->cdev,
1287				     "Bad dgram length: %#X\n", dg_len);
1288				goto err;
1289			}
1290			if (ncm->is_crc) {
1291				uint32_t crc, crc2;
1292
1293				crc = get_unaligned_le32(ntb_ptr +
1294							 index + dg_len -
1295							 crc_len);
1296				crc2 = ~crc32_le(~0,
1297						 ntb_ptr + index,
1298						 dg_len - crc_len);
1299				if (crc != crc2) {
1300					INFO(port->func.config->cdev,
1301					     "Bad CRC\n");
1302					goto err;
1303				}
1304			}
1305
1306			index2 = get_ncm(&tmp, opts->dgram_item_len);
1307			dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1308
1309			/* wDatagramIndex[1] */
1310			if (index2 > block_len - opts->dpe_size) {
1311				INFO(port->func.config->cdev,
1312				     "Bad index: %#X\n", index2);
1313				goto err;
1314			}
1315
1316			/*
1317			 * Copy the data into a new skb.
1318			 * This ensures the truesize is correct
1319			 */
1320			skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1321							 dg_len - crc_len);
1322			if (skb2 == NULL)
1323				goto err;
1324			skb_put_data(skb2, ntb_ptr + index,
1325				     dg_len - crc_len);
1326
1327			skb_queue_tail(list, skb2);
1328
1329			ndp_len -= 2 * (opts->dgram_item_len * 2);
1330
1331			dgram_counter++;
1332			if (index2 == 0 || dg_len2 == 0)
1333				break;
1334		} while (ndp_len > 2 * (opts->dgram_item_len * 2));
1335	} while (ndp_index);
1336
1337	VDBG(port->func.config->cdev,
1338	     "Parsed NTB with %d frames\n", dgram_counter);
1339
1340	to_process -= block_len;
1341
1342	/*
1343	 * Windows NCM driver avoids USB ZLPs by adding a 1-byte
1344	 * zero pad as needed.
1345	 */
1346	if (to_process == 1 &&
1347	    (*(unsigned char *)(ntb_ptr + block_len) == 0x00)) {
1348		to_process--;
1349	} else if ((to_process > 0) && (block_len != 0)) {
1350		ntb_ptr = (unsigned char *)(ntb_ptr + block_len);
1351		goto parse_ntb;
1352	}
1353
1354	dev_consume_skb_any(skb);
1355
1356	return 0;
1357err:
1358	skb_queue_purge(list);
1359	dev_kfree_skb_any(skb);
1360	return ret;
1361}
1362
1363static void ncm_disable(struct usb_function *f)
1364{
1365	struct f_ncm		*ncm = func_to_ncm(f);
1366	struct usb_composite_dev *cdev = f->config->cdev;
1367
1368	DBG(cdev, "ncm deactivated\n");
1369
1370	if (ncm->netdev) {
1371		ncm->netdev = NULL;
1372		gether_disconnect(&ncm->port);
1373	}
1374
1375	if (ncm->notify->enabled) {
1376		usb_ep_disable(ncm->notify);
1377		ncm->notify->desc = NULL;
1378	}
1379}
1380
1381/*-------------------------------------------------------------------------*/
1382
1383/*
1384 * Callbacks let us notify the host about connect/disconnect when the
1385 * net device is opened or closed.
1386 *
1387 * For testing, note that link states on this side include both opened
1388 * and closed variants of:
1389 *
1390 *   - disconnected/unconfigured
1391 *   - configured but inactive (data alt 0)
1392 *   - configured and active (data alt 1)
1393 *
1394 * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1395 * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1396 * imply the host is actually polling the notification endpoint, and
1397 * likewise that "active" doesn't imply it's actually using the data
1398 * endpoints for traffic.
1399 */
1400
1401static void ncm_open(struct gether *geth)
1402{
1403	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1404
1405	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1406
1407	spin_lock(&ncm->lock);
1408	ncm->is_open = true;
1409	ncm_notify(ncm);
1410	spin_unlock(&ncm->lock);
1411}
1412
1413static void ncm_close(struct gether *geth)
1414{
1415	struct f_ncm		*ncm = func_to_ncm(&geth->func);
1416
1417	DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1418
1419	spin_lock(&ncm->lock);
1420	ncm->is_open = false;
1421	ncm_notify(ncm);
1422	spin_unlock(&ncm->lock);
1423}
1424
1425/*-------------------------------------------------------------------------*/
1426
1427/* ethernet function driver setup/binding */
1428
1429static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1430{
1431	struct usb_composite_dev *cdev = c->cdev;
1432	struct f_ncm		*ncm = func_to_ncm(f);
1433	struct usb_string	*us;
1434	int			status = 0;
1435	struct usb_ep		*ep;
1436	struct f_ncm_opts	*ncm_opts;
1437
1438	if (!can_support_ecm(cdev->gadget))
1439		return -EINVAL;
1440
1441	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1442
1443	if (cdev->use_os_string) {
1444		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
1445					   GFP_KERNEL);
1446		if (!f->os_desc_table)
1447			return -ENOMEM;
1448		f->os_desc_n = 1;
1449		f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
1450	}
1451
1452	mutex_lock(&ncm_opts->lock);
1453	gether_set_gadget(ncm_opts->net, cdev->gadget);
1454	if (!ncm_opts->bound) {
1455		ncm_opts->net->mtu = (ncm_opts->max_segment_size - ETH_HLEN);
1456		status = gether_register_netdev(ncm_opts->net);
1457	}
1458	mutex_unlock(&ncm_opts->lock);
1459
1460	if (status)
1461		goto fail;
1462
1463	ncm_opts->bound = true;
1464
1465	us = usb_gstrings_attach(cdev, ncm_strings,
1466				 ARRAY_SIZE(ncm_string_defs));
1467	if (IS_ERR(us)) {
1468		status = PTR_ERR(us);
1469		goto fail;
1470	}
1471	ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1472	ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1473	ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1474	ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1475	ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1476
1477	/* allocate instance-specific interface IDs */
1478	status = usb_interface_id(c, f);
1479	if (status < 0)
1480		goto fail;
1481	ncm->ctrl_id = status;
1482	ncm_iad_desc.bFirstInterface = status;
1483
1484	ncm_control_intf.bInterfaceNumber = status;
1485	ncm_union_desc.bMasterInterface0 = status;
1486
1487	if (cdev->use_os_string)
1488		f->os_desc_table[0].if_id =
1489			ncm_iad_desc.bFirstInterface;
1490
1491	status = usb_interface_id(c, f);
1492	if (status < 0)
1493		goto fail;
1494	ncm->data_id = status;
1495
1496	ncm_data_nop_intf.bInterfaceNumber = status;
1497	ncm_data_intf.bInterfaceNumber = status;
1498	ncm_union_desc.bSlaveInterface0 = status;
1499
1500	ecm_desc.wMaxSegmentSize = cpu_to_le16(ncm_opts->max_segment_size);
1501
1502	status = -ENODEV;
1503
1504	/* allocate instance-specific endpoints */
1505	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1506	if (!ep)
1507		goto fail;
1508	ncm->port.in_ep = ep;
1509
1510	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1511	if (!ep)
1512		goto fail;
1513	ncm->port.out_ep = ep;
1514
1515	ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1516	if (!ep)
1517		goto fail;
1518	ncm->notify = ep;
1519
1520	status = -ENOMEM;
1521
1522	/* allocate notification request and buffer */
1523	ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1524	if (!ncm->notify_req)
1525		goto fail;
1526	ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1527	if (!ncm->notify_req->buf)
1528		goto fail;
1529	ncm->notify_req->context = ncm;
1530	ncm->notify_req->complete = ncm_notify_complete;
1531
1532	/*
1533	 * support all relevant hardware speeds... we expect that when
1534	 * hardware is dual speed, all bulk-capable endpoints work at
1535	 * both speeds
1536	 */
1537	hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1538	hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1539	hs_ncm_notify_desc.bEndpointAddress =
1540		fs_ncm_notify_desc.bEndpointAddress;
1541
1542	ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1543	ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1544	ss_ncm_notify_desc.bEndpointAddress =
1545		fs_ncm_notify_desc.bEndpointAddress;
1546
1547	status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1548			ncm_ss_function, ncm_ss_function);
1549	if (status)
1550		goto fail;
1551
1552	/*
1553	 * NOTE:  all that is done without knowing or caring about
1554	 * the network link ... which is unavailable to this code
1555	 * until we're activated via set_alt().
1556	 */
1557
1558	ncm->port.open = ncm_open;
1559	ncm->port.close = ncm_close;
1560
1561	hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
1562	ncm->task_timer.function = ncm_tx_timeout;
1563
1564	DBG(cdev, "CDC Network: IN/%s OUT/%s NOTIFY/%s\n",
1565			ncm->port.in_ep->name, ncm->port.out_ep->name,
1566			ncm->notify->name);
1567	return 0;
1568
1569fail:
1570	kfree(f->os_desc_table);
1571	f->os_desc_n = 0;
1572
1573	if (ncm->notify_req) {
1574		kfree(ncm->notify_req->buf);
1575		usb_ep_free_request(ncm->notify, ncm->notify_req);
1576	}
1577
1578	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1579
1580	return status;
1581}
1582
1583static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1584{
1585	return container_of(to_config_group(item), struct f_ncm_opts,
1586			    func_inst.group);
1587}
1588
1589/* f_ncm_item_ops */
1590USB_ETHERNET_CONFIGFS_ITEM(ncm);
1591
1592/* f_ncm_opts_dev_addr */
1593USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1594
1595/* f_ncm_opts_host_addr */
1596USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1597
1598/* f_ncm_opts_qmult */
1599USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1600
1601/* f_ncm_opts_ifname */
1602USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1603
1604static ssize_t ncm_opts_max_segment_size_show(struct config_item *item,
1605					      char *page)
1606{
1607	struct f_ncm_opts *opts = to_f_ncm_opts(item);
1608	u16 segment_size;
1609
1610	mutex_lock(&opts->lock);
1611	segment_size = opts->max_segment_size;
1612	mutex_unlock(&opts->lock);
1613
1614	return sysfs_emit(page, "%u\n", segment_size);
1615}
1616
1617static ssize_t ncm_opts_max_segment_size_store(struct config_item *item,
1618					       const char *page, size_t len)
1619{
1620	struct f_ncm_opts *opts = to_f_ncm_opts(item);
1621	u16 segment_size;
1622	int ret;
1623
1624	mutex_lock(&opts->lock);
1625	if (opts->refcnt) {
1626		ret = -EBUSY;
1627		goto out;
1628	}
1629
1630	ret = kstrtou16(page, 0, &segment_size);
1631	if (ret)
1632		goto out;
1633
1634	if (segment_size > MAX_DATAGRAM_SIZE) {
1635		ret = -EINVAL;
1636		goto out;
1637	}
1638
1639	opts->max_segment_size = segment_size;
1640	ret = len;
1641out:
1642	mutex_unlock(&opts->lock);
1643	return ret;
1644}
1645
1646CONFIGFS_ATTR(ncm_opts_, max_segment_size);
1647
1648static struct configfs_attribute *ncm_attrs[] = {
1649	&ncm_opts_attr_dev_addr,
1650	&ncm_opts_attr_host_addr,
1651	&ncm_opts_attr_qmult,
1652	&ncm_opts_attr_ifname,
1653	&ncm_opts_attr_max_segment_size,
1654	NULL,
1655};
1656
1657static const struct config_item_type ncm_func_type = {
1658	.ct_item_ops	= &ncm_item_ops,
1659	.ct_attrs	= ncm_attrs,
1660	.ct_owner	= THIS_MODULE,
1661};
1662
1663static void ncm_free_inst(struct usb_function_instance *f)
1664{
1665	struct f_ncm_opts *opts;
1666
1667	opts = container_of(f, struct f_ncm_opts, func_inst);
1668	if (opts->bound)
1669		gether_cleanup(netdev_priv(opts->net));
1670	else
1671		free_netdev(opts->net);
1672	kfree(opts->ncm_interf_group);
1673	kfree(opts);
1674}
1675
1676static struct usb_function_instance *ncm_alloc_inst(void)
1677{
1678	struct f_ncm_opts *opts;
1679	struct usb_os_desc *descs[1];
1680	char *names[1];
1681	struct config_group *ncm_interf_group;
1682
1683	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1684	if (!opts)
1685		return ERR_PTR(-ENOMEM);
1686	opts->ncm_os_desc.ext_compat_id = opts->ncm_ext_compat_id;
1687
1688	mutex_init(&opts->lock);
1689	opts->func_inst.free_func_inst = ncm_free_inst;
1690	opts->net = gether_setup_default();
1691	if (IS_ERR(opts->net)) {
1692		struct net_device *net = opts->net;
1693		kfree(opts);
1694		return ERR_CAST(net);
1695	}
1696	opts->max_segment_size = ETH_FRAME_LEN;
1697	INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
1698
1699	descs[0] = &opts->ncm_os_desc;
1700	names[0] = "ncm";
1701
1702	config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1703	ncm_interf_group =
1704		usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
1705					       names, THIS_MODULE);
1706	if (IS_ERR(ncm_interf_group)) {
1707		ncm_free_inst(&opts->func_inst);
1708		return ERR_CAST(ncm_interf_group);
1709	}
1710	opts->ncm_interf_group = ncm_interf_group;
1711
1712	return &opts->func_inst;
1713}
1714
1715static void ncm_free(struct usb_function *f)
1716{
1717	struct f_ncm *ncm;
1718	struct f_ncm_opts *opts;
1719
1720	ncm = func_to_ncm(f);
1721	opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1722	kfree(ncm);
1723	mutex_lock(&opts->lock);
1724	opts->refcnt--;
1725	mutex_unlock(&opts->lock);
1726}
1727
1728static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1729{
1730	struct f_ncm *ncm = func_to_ncm(f);
1731
1732	DBG(c->cdev, "ncm unbind\n");
1733
1734	hrtimer_cancel(&ncm->task_timer);
1735
1736	kfree(f->os_desc_table);
1737	f->os_desc_n = 0;
1738
1739	ncm_string_defs[0].id = 0;
1740	usb_free_all_descriptors(f);
1741
1742	if (atomic_read(&ncm->notify_count)) {
1743		usb_ep_dequeue(ncm->notify, ncm->notify_req);
1744		atomic_set(&ncm->notify_count, 0);
1745	}
1746
1747	kfree(ncm->notify_req->buf);
1748	usb_ep_free_request(ncm->notify, ncm->notify_req);
1749}
1750
1751static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1752{
1753	struct f_ncm		*ncm;
1754	struct f_ncm_opts	*opts;
1755	int status;
1756
1757	/* allocate and initialize one new instance */
1758	ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1759	if (!ncm)
1760		return ERR_PTR(-ENOMEM);
1761
1762	opts = container_of(fi, struct f_ncm_opts, func_inst);
1763	mutex_lock(&opts->lock);
1764	opts->refcnt++;
1765
1766	/* export host's Ethernet address in CDC format */
1767	status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1768				      sizeof(ncm->ethaddr));
1769	if (status < 12) { /* strlen("01234567890a") */
1770		kfree(ncm);
1771		mutex_unlock(&opts->lock);
1772		return ERR_PTR(-EINVAL);
1773	}
1774	ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1775
1776	spin_lock_init(&ncm->lock);
1777	ncm_reset_values(ncm);
1778	ncm->port.ioport = netdev_priv(opts->net);
1779	mutex_unlock(&opts->lock);
1780	ncm->port.is_fixed = true;
1781	ncm->port.supports_multi_frame = true;
1782
1783	ncm->port.func.name = "cdc_network";
1784	/* descriptors are per-instance copies */
1785	ncm->port.func.bind = ncm_bind;
1786	ncm->port.func.unbind = ncm_unbind;
1787	ncm->port.func.set_alt = ncm_set_alt;
1788	ncm->port.func.get_alt = ncm_get_alt;
1789	ncm->port.func.setup = ncm_setup;
1790	ncm->port.func.disable = ncm_disable;
1791	ncm->port.func.free_func = ncm_free;
1792
1793	ncm->port.wrap = ncm_wrap_ntb;
1794	ncm->port.unwrap = ncm_unwrap_ntb;
1795
1796	return &ncm->port.func;
1797}
1798
1799DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1800MODULE_LICENSE("GPL");
1801MODULE_AUTHOR("Yauheni Kaliuta");
1802