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v3.1
  1/*
  2 * f_ecm.c -- USB CDC Ethernet (ECM) link function driver
  3 *
  4 * Copyright (C) 2003-2005,2008 David Brownell
  5 * Copyright (C) 2008 Nokia Corporation
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 20 */
 21
 22/* #define VERBOSE_DEBUG */
 23
 24#include <linux/slab.h>
 25#include <linux/kernel.h>
 
 26#include <linux/device.h>
 27#include <linux/etherdevice.h>
 28
 29#include "u_ether.h"
 
 
 30
 31
 32/*
 33 * This function is a "CDC Ethernet Networking Control Model" (CDC ECM)
 34 * Ethernet link.  The data transfer model is simple (packets sent and
 35 * received over bulk endpoints using normal short packet termination),
 36 * and the control model exposes various data and optional notifications.
 37 *
 38 * ECM is well standardized and (except for Microsoft) supported by most
 39 * operating systems with USB host support.  It's the preferred interop
 40 * solution for Ethernet over USB, at least for firmware based solutions.
 41 * (Hardware solutions tend to be more minimalist.)  A newer and simpler
 42 * "Ethernet Emulation Model" (CDC EEM) hasn't yet caught on.
 43 *
 44 * Note that ECM requires the use of "alternate settings" for its data
 45 * interface.  This means that the set_alt() method has real work to do,
 46 * and also means that a get_alt() method is required.
 47 */
 48
 49
 50enum ecm_notify_state {
 51	ECM_NOTIFY_NONE,		/* don't notify */
 52	ECM_NOTIFY_CONNECT,		/* issue CONNECT next */
 53	ECM_NOTIFY_SPEED,		/* issue SPEED_CHANGE next */
 54};
 55
 56struct f_ecm {
 57	struct gether			port;
 58	u8				ctrl_id, data_id;
 59
 60	char				ethaddr[14];
 61
 62	struct usb_ep			*notify;
 63	struct usb_request		*notify_req;
 64	u8				notify_state;
 65	bool				is_open;
 66
 67	/* FIXME is_open needs some irq-ish locking
 68	 * ... possibly the same as port.ioport
 69	 */
 70};
 71
 72static inline struct f_ecm *func_to_ecm(struct usb_function *f)
 73{
 74	return container_of(f, struct f_ecm, port.func);
 75}
 76
 77/* peak (theoretical) bulk transfer rate in bits-per-second */
 78static inline unsigned ecm_bitrate(struct usb_gadget *g)
 79{
 80	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
 81		return 13 * 1024 * 8 * 1000 * 8;
 82	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 83		return 13 * 512 * 8 * 1000 * 8;
 84	else
 85		return 19 * 64 * 1 * 1000 * 8;
 86}
 87
 88/*-------------------------------------------------------------------------*/
 89
 90/*
 91 * Include the status endpoint if we can, even though it's optional.
 92 *
 93 * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 94 * packet, to simplify cancellation; and a big transfer interval, to
 95 * waste less bandwidth.
 96 *
 97 * Some drivers (like Linux 2.4 cdc-ether!) "need" it to exist even
 98 * if they ignore the connect/disconnect notifications that real aether
 99 * can provide.  More advanced cdc configurations might want to support
100 * encapsulated commands (vendor-specific, using control-OUT).
101 */
102
103#define LOG2_STATUS_INTERVAL_MSEC	5	/* 1 << 5 == 32 msec */
104#define ECM_STATUS_BYTECOUNT		16	/* 8 byte header + data */
105
106
107/* interface descriptor: */
108
 
 
 
 
 
 
 
 
 
 
 
 
 
 
109static struct usb_interface_descriptor ecm_control_intf = {
110	.bLength =		sizeof ecm_control_intf,
111	.bDescriptorType =	USB_DT_INTERFACE,
112
113	/* .bInterfaceNumber = DYNAMIC */
114	/* status endpoint is optional; this could be patched later */
115	.bNumEndpoints =	1,
116	.bInterfaceClass =	USB_CLASS_COMM,
117	.bInterfaceSubClass =	USB_CDC_SUBCLASS_ETHERNET,
118	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
119	/* .iInterface = DYNAMIC */
120};
121
122static struct usb_cdc_header_desc ecm_header_desc = {
123	.bLength =		sizeof ecm_header_desc,
124	.bDescriptorType =	USB_DT_CS_INTERFACE,
125	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
126
127	.bcdCDC =		cpu_to_le16(0x0110),
128};
129
130static struct usb_cdc_union_desc ecm_union_desc = {
131	.bLength =		sizeof(ecm_union_desc),
132	.bDescriptorType =	USB_DT_CS_INTERFACE,
133	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
134	/* .bMasterInterface0 =	DYNAMIC */
135	/* .bSlaveInterface0 =	DYNAMIC */
136};
137
138static struct usb_cdc_ether_desc ecm_desc = {
139	.bLength =		sizeof ecm_desc,
140	.bDescriptorType =	USB_DT_CS_INTERFACE,
141	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
142
143	/* this descriptor actually adds value, surprise! */
144	/* .iMACAddress = DYNAMIC */
145	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
146	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
147	.wNumberMCFilters =	cpu_to_le16(0),
148	.bNumberPowerFilters =	0,
149};
150
151/* the default data interface has no endpoints ... */
152
153static struct usb_interface_descriptor ecm_data_nop_intf = {
154	.bLength =		sizeof ecm_data_nop_intf,
155	.bDescriptorType =	USB_DT_INTERFACE,
156
157	.bInterfaceNumber =	1,
158	.bAlternateSetting =	0,
159	.bNumEndpoints =	0,
160	.bInterfaceClass =	USB_CLASS_CDC_DATA,
161	.bInterfaceSubClass =	0,
162	.bInterfaceProtocol =	0,
163	/* .iInterface = DYNAMIC */
164};
165
166/* ... but the "real" data interface has two bulk endpoints */
167
168static struct usb_interface_descriptor ecm_data_intf = {
169	.bLength =		sizeof ecm_data_intf,
170	.bDescriptorType =	USB_DT_INTERFACE,
171
172	.bInterfaceNumber =	1,
173	.bAlternateSetting =	1,
174	.bNumEndpoints =	2,
175	.bInterfaceClass =	USB_CLASS_CDC_DATA,
176	.bInterfaceSubClass =	0,
177	.bInterfaceProtocol =	0,
178	/* .iInterface = DYNAMIC */
179};
180
181/* full speed support: */
182
183static struct usb_endpoint_descriptor fs_ecm_notify_desc = {
184	.bLength =		USB_DT_ENDPOINT_SIZE,
185	.bDescriptorType =	USB_DT_ENDPOINT,
186
187	.bEndpointAddress =	USB_DIR_IN,
188	.bmAttributes =		USB_ENDPOINT_XFER_INT,
189	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
190	.bInterval =		1 << LOG2_STATUS_INTERVAL_MSEC,
191};
192
193static struct usb_endpoint_descriptor fs_ecm_in_desc = {
194	.bLength =		USB_DT_ENDPOINT_SIZE,
195	.bDescriptorType =	USB_DT_ENDPOINT,
196
197	.bEndpointAddress =	USB_DIR_IN,
198	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
199};
200
201static struct usb_endpoint_descriptor fs_ecm_out_desc = {
202	.bLength =		USB_DT_ENDPOINT_SIZE,
203	.bDescriptorType =	USB_DT_ENDPOINT,
204
205	.bEndpointAddress =	USB_DIR_OUT,
206	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
207};
208
209static struct usb_descriptor_header *ecm_fs_function[] = {
210	/* CDC ECM control descriptors */
 
211	(struct usb_descriptor_header *) &ecm_control_intf,
212	(struct usb_descriptor_header *) &ecm_header_desc,
213	(struct usb_descriptor_header *) &ecm_union_desc,
214	(struct usb_descriptor_header *) &ecm_desc,
215
216	/* NOTE: status endpoint might need to be removed */
217	(struct usb_descriptor_header *) &fs_ecm_notify_desc,
218
219	/* data interface, altsettings 0 and 1 */
220	(struct usb_descriptor_header *) &ecm_data_nop_intf,
221	(struct usb_descriptor_header *) &ecm_data_intf,
222	(struct usb_descriptor_header *) &fs_ecm_in_desc,
223	(struct usb_descriptor_header *) &fs_ecm_out_desc,
224	NULL,
225};
226
227/* high speed support: */
228
229static struct usb_endpoint_descriptor hs_ecm_notify_desc = {
230	.bLength =		USB_DT_ENDPOINT_SIZE,
231	.bDescriptorType =	USB_DT_ENDPOINT,
232
233	.bEndpointAddress =	USB_DIR_IN,
234	.bmAttributes =		USB_ENDPOINT_XFER_INT,
235	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
236	.bInterval =		LOG2_STATUS_INTERVAL_MSEC + 4,
237};
238
239static struct usb_endpoint_descriptor hs_ecm_in_desc = {
240	.bLength =		USB_DT_ENDPOINT_SIZE,
241	.bDescriptorType =	USB_DT_ENDPOINT,
242
243	.bEndpointAddress =	USB_DIR_IN,
244	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
245	.wMaxPacketSize =	cpu_to_le16(512),
246};
247
248static struct usb_endpoint_descriptor hs_ecm_out_desc = {
249	.bLength =		USB_DT_ENDPOINT_SIZE,
250	.bDescriptorType =	USB_DT_ENDPOINT,
251
252	.bEndpointAddress =	USB_DIR_OUT,
253	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
254	.wMaxPacketSize =	cpu_to_le16(512),
255};
256
257static struct usb_descriptor_header *ecm_hs_function[] = {
258	/* CDC ECM control descriptors */
 
259	(struct usb_descriptor_header *) &ecm_control_intf,
260	(struct usb_descriptor_header *) &ecm_header_desc,
261	(struct usb_descriptor_header *) &ecm_union_desc,
262	(struct usb_descriptor_header *) &ecm_desc,
263
264	/* NOTE: status endpoint might need to be removed */
265	(struct usb_descriptor_header *) &hs_ecm_notify_desc,
266
267	/* data interface, altsettings 0 and 1 */
268	(struct usb_descriptor_header *) &ecm_data_nop_intf,
269	(struct usb_descriptor_header *) &ecm_data_intf,
270	(struct usb_descriptor_header *) &hs_ecm_in_desc,
271	(struct usb_descriptor_header *) &hs_ecm_out_desc,
272	NULL,
273};
274
275/* super speed support: */
276
277static struct usb_endpoint_descriptor ss_ecm_notify_desc = {
278	.bLength =		USB_DT_ENDPOINT_SIZE,
279	.bDescriptorType =	USB_DT_ENDPOINT,
280
281	.bEndpointAddress =	USB_DIR_IN,
282	.bmAttributes =		USB_ENDPOINT_XFER_INT,
283	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
284	.bInterval =		LOG2_STATUS_INTERVAL_MSEC + 4,
285};
286
287static struct usb_ss_ep_comp_descriptor ss_ecm_intr_comp_desc = {
288	.bLength =		sizeof ss_ecm_intr_comp_desc,
289	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
290
291	/* the following 3 values can be tweaked if necessary */
292	/* .bMaxBurst =		0, */
293	/* .bmAttributes =	0, */
294	.wBytesPerInterval =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
295};
296
297static struct usb_endpoint_descriptor ss_ecm_in_desc = {
298	.bLength =		USB_DT_ENDPOINT_SIZE,
299	.bDescriptorType =	USB_DT_ENDPOINT,
300
301	.bEndpointAddress =	USB_DIR_IN,
302	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
303	.wMaxPacketSize =	cpu_to_le16(1024),
304};
305
306static struct usb_endpoint_descriptor ss_ecm_out_desc = {
307	.bLength =		USB_DT_ENDPOINT_SIZE,
308	.bDescriptorType =	USB_DT_ENDPOINT,
309
310	.bEndpointAddress =	USB_DIR_OUT,
311	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
312	.wMaxPacketSize =	cpu_to_le16(1024),
313};
314
315static struct usb_ss_ep_comp_descriptor ss_ecm_bulk_comp_desc = {
316	.bLength =		sizeof ss_ecm_bulk_comp_desc,
317	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
318
319	/* the following 2 values can be tweaked if necessary */
320	/* .bMaxBurst =		0, */
321	/* .bmAttributes =	0, */
322};
323
324static struct usb_descriptor_header *ecm_ss_function[] = {
325	/* CDC ECM control descriptors */
 
326	(struct usb_descriptor_header *) &ecm_control_intf,
327	(struct usb_descriptor_header *) &ecm_header_desc,
328	(struct usb_descriptor_header *) &ecm_union_desc,
329	(struct usb_descriptor_header *) &ecm_desc,
330
331	/* NOTE: status endpoint might need to be removed */
332	(struct usb_descriptor_header *) &ss_ecm_notify_desc,
333	(struct usb_descriptor_header *) &ss_ecm_intr_comp_desc,
334
335	/* data interface, altsettings 0 and 1 */
336	(struct usb_descriptor_header *) &ecm_data_nop_intf,
337	(struct usb_descriptor_header *) &ecm_data_intf,
338	(struct usb_descriptor_header *) &ss_ecm_in_desc,
339	(struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
340	(struct usb_descriptor_header *) &ss_ecm_out_desc,
341	(struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
342	NULL,
343};
344
345/* string descriptors: */
346
347static struct usb_string ecm_string_defs[] = {
348	[0].s = "CDC Ethernet Control Model (ECM)",
349	[1].s = NULL /* DYNAMIC */,
350	[2].s = "CDC Ethernet Data",
 
351	{  } /* end of list */
352};
353
354static struct usb_gadget_strings ecm_string_table = {
355	.language =		0x0409,	/* en-us */
356	.strings =		ecm_string_defs,
357};
358
359static struct usb_gadget_strings *ecm_strings[] = {
360	&ecm_string_table,
361	NULL,
362};
363
364/*-------------------------------------------------------------------------*/
365
366static void ecm_do_notify(struct f_ecm *ecm)
367{
368	struct usb_request		*req = ecm->notify_req;
369	struct usb_cdc_notification	*event;
370	struct usb_composite_dev	*cdev = ecm->port.func.config->cdev;
371	__le32				*data;
372	int				status;
373
374	/* notification already in flight? */
375	if (!req)
376		return;
377
378	event = req->buf;
379	switch (ecm->notify_state) {
380	case ECM_NOTIFY_NONE:
381		return;
382
383	case ECM_NOTIFY_CONNECT:
384		event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
385		if (ecm->is_open)
386			event->wValue = cpu_to_le16(1);
387		else
388			event->wValue = cpu_to_le16(0);
389		event->wLength = 0;
390		req->length = sizeof *event;
391
392		DBG(cdev, "notify connect %s\n",
393				ecm->is_open ? "true" : "false");
394		ecm->notify_state = ECM_NOTIFY_SPEED;
395		break;
396
397	case ECM_NOTIFY_SPEED:
398		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
399		event->wValue = cpu_to_le16(0);
400		event->wLength = cpu_to_le16(8);
401		req->length = ECM_STATUS_BYTECOUNT;
402
403		/* SPEED_CHANGE data is up/down speeds in bits/sec */
404		data = req->buf + sizeof *event;
405		data[0] = cpu_to_le32(ecm_bitrate(cdev->gadget));
406		data[1] = data[0];
407
408		DBG(cdev, "notify speed %d\n", ecm_bitrate(cdev->gadget));
409		ecm->notify_state = ECM_NOTIFY_NONE;
410		break;
411	}
412	event->bmRequestType = 0xA1;
413	event->wIndex = cpu_to_le16(ecm->ctrl_id);
414
415	ecm->notify_req = NULL;
416	status = usb_ep_queue(ecm->notify, req, GFP_ATOMIC);
417	if (status < 0) {
418		ecm->notify_req = req;
419		DBG(cdev, "notify --> %d\n", status);
420	}
421}
422
423static void ecm_notify(struct f_ecm *ecm)
424{
425	/* NOTE on most versions of Linux, host side cdc-ethernet
426	 * won't listen for notifications until its netdevice opens.
427	 * The first notification then sits in the FIFO for a long
428	 * time, and the second one is queued.
429	 */
430	ecm->notify_state = ECM_NOTIFY_CONNECT;
431	ecm_do_notify(ecm);
432}
433
434static void ecm_notify_complete(struct usb_ep *ep, struct usb_request *req)
435{
436	struct f_ecm			*ecm = req->context;
437	struct usb_composite_dev	*cdev = ecm->port.func.config->cdev;
438	struct usb_cdc_notification	*event = req->buf;
439
440	switch (req->status) {
441	case 0:
442		/* no fault */
443		break;
444	case -ECONNRESET:
445	case -ESHUTDOWN:
446		ecm->notify_state = ECM_NOTIFY_NONE;
447		break;
448	default:
449		DBG(cdev, "event %02x --> %d\n",
450			event->bNotificationType, req->status);
451		break;
452	}
453	ecm->notify_req = req;
454	ecm_do_notify(ecm);
455}
456
457static int ecm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
458{
459	struct f_ecm		*ecm = func_to_ecm(f);
460	struct usb_composite_dev *cdev = f->config->cdev;
461	struct usb_request	*req = cdev->req;
462	int			value = -EOPNOTSUPP;
463	u16			w_index = le16_to_cpu(ctrl->wIndex);
464	u16			w_value = le16_to_cpu(ctrl->wValue);
465	u16			w_length = le16_to_cpu(ctrl->wLength);
466
467	/* composite driver infrastructure handles everything except
468	 * CDC class messages; interface activation uses set_alt().
469	 */
470	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
471	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
472			| USB_CDC_SET_ETHERNET_PACKET_FILTER:
473		/* see 6.2.30: no data, wIndex = interface,
474		 * wValue = packet filter bitmap
475		 */
476		if (w_length != 0 || w_index != ecm->ctrl_id)
477			goto invalid;
478		DBG(cdev, "packet filter %02x\n", w_value);
479		/* REVISIT locking of cdc_filter.  This assumes the UDC
480		 * driver won't have a concurrent packet TX irq running on
481		 * another CPU; or that if it does, this write is atomic...
482		 */
483		ecm->port.cdc_filter = w_value;
484		value = 0;
485		break;
486
487	/* and optionally:
488	 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
489	 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
490	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
491	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
492	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
493	 * case USB_CDC_GET_ETHERNET_STATISTIC:
494	 */
495
496	default:
497invalid:
498		DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
499			ctrl->bRequestType, ctrl->bRequest,
500			w_value, w_index, w_length);
501	}
502
503	/* respond with data transfer or status phase? */
504	if (value >= 0) {
505		DBG(cdev, "ecm req%02x.%02x v%04x i%04x l%d\n",
506			ctrl->bRequestType, ctrl->bRequest,
507			w_value, w_index, w_length);
508		req->zero = 0;
509		req->length = value;
510		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
511		if (value < 0)
512			ERROR(cdev, "ecm req %02x.%02x response err %d\n",
513					ctrl->bRequestType, ctrl->bRequest,
514					value);
515	}
516
517	/* device either stalls (value < 0) or reports success */
518	return value;
519}
520
521
522static int ecm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
523{
524	struct f_ecm		*ecm = func_to_ecm(f);
525	struct usb_composite_dev *cdev = f->config->cdev;
526
527	/* Control interface has only altsetting 0 */
528	if (intf == ecm->ctrl_id) {
529		if (alt != 0)
530			goto fail;
531
532		if (ecm->notify->driver_data) {
533			VDBG(cdev, "reset ecm control %d\n", intf);
534			usb_ep_disable(ecm->notify);
535		}
536		if (!(ecm->notify->desc)) {
537			VDBG(cdev, "init ecm ctrl %d\n", intf);
538			if (config_ep_by_speed(cdev->gadget, f, ecm->notify))
539				goto fail;
540		}
541		usb_ep_enable(ecm->notify);
542		ecm->notify->driver_data = ecm;
543
544	/* Data interface has two altsettings, 0 and 1 */
545	} else if (intf == ecm->data_id) {
546		if (alt > 1)
547			goto fail;
548
549		if (ecm->port.in_ep->driver_data) {
550			DBG(cdev, "reset ecm\n");
551			gether_disconnect(&ecm->port);
552		}
553
554		if (!ecm->port.in_ep->desc ||
555		    !ecm->port.out_ep->desc) {
556			DBG(cdev, "init ecm\n");
557			if (config_ep_by_speed(cdev->gadget, f,
558					       ecm->port.in_ep) ||
559			    config_ep_by_speed(cdev->gadget, f,
560					       ecm->port.out_ep)) {
561				ecm->port.in_ep->desc = NULL;
562				ecm->port.out_ep->desc = NULL;
563				goto fail;
564			}
565		}
566
567		/* CDC Ethernet only sends data in non-default altsettings.
568		 * Changing altsettings resets filters, statistics, etc.
569		 */
570		if (alt == 1) {
571			struct net_device	*net;
572
573			/* Enable zlps by default for ECM conformance;
574			 * override for musb_hdrc (avoids txdma ovhead).
575			 */
576			ecm->port.is_zlp_ok = !(gadget_is_musbhdrc(cdev->gadget)
577				);
578			ecm->port.cdc_filter = DEFAULT_FILTER;
579			DBG(cdev, "activate ecm\n");
580			net = gether_connect(&ecm->port);
581			if (IS_ERR(net))
582				return PTR_ERR(net);
583		}
584
585		/* NOTE this can be a minor disagreement with the ECM spec,
586		 * which says speed notifications will "always" follow
587		 * connection notifications.  But we allow one connect to
588		 * follow another (if the first is in flight), and instead
589		 * just guarantee that a speed notification is always sent.
590		 */
591		ecm_notify(ecm);
592	} else
593		goto fail;
594
595	return 0;
596fail:
597	return -EINVAL;
598}
599
600/* Because the data interface supports multiple altsettings,
601 * this ECM function *MUST* implement a get_alt() method.
602 */
603static int ecm_get_alt(struct usb_function *f, unsigned intf)
604{
605	struct f_ecm		*ecm = func_to_ecm(f);
606
607	if (intf == ecm->ctrl_id)
608		return 0;
609	return ecm->port.in_ep->driver_data ? 1 : 0;
610}
611
612static void ecm_disable(struct usb_function *f)
613{
614	struct f_ecm		*ecm = func_to_ecm(f);
615	struct usb_composite_dev *cdev = f->config->cdev;
616
617	DBG(cdev, "ecm deactivated\n");
618
619	if (ecm->port.in_ep->driver_data)
620		gether_disconnect(&ecm->port);
621
622	if (ecm->notify->driver_data) {
623		usb_ep_disable(ecm->notify);
624		ecm->notify->driver_data = NULL;
625		ecm->notify->desc = NULL;
626	}
627}
628
629/*-------------------------------------------------------------------------*/
630
631/*
632 * Callbacks let us notify the host about connect/disconnect when the
633 * net device is opened or closed.
634 *
635 * For testing, note that link states on this side include both opened
636 * and closed variants of:
637 *
638 *   - disconnected/unconfigured
639 *   - configured but inactive (data alt 0)
640 *   - configured and active (data alt 1)
641 *
642 * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
643 * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
644 * imply the host is actually polling the notification endpoint, and
645 * likewise that "active" doesn't imply it's actually using the data
646 * endpoints for traffic.
647 */
648
649static void ecm_open(struct gether *geth)
650{
651	struct f_ecm		*ecm = func_to_ecm(&geth->func);
652
653	DBG(ecm->port.func.config->cdev, "%s\n", __func__);
654
655	ecm->is_open = true;
656	ecm_notify(ecm);
657}
658
659static void ecm_close(struct gether *geth)
660{
661	struct f_ecm		*ecm = func_to_ecm(&geth->func);
662
663	DBG(ecm->port.func.config->cdev, "%s\n", __func__);
664
665	ecm->is_open = false;
666	ecm_notify(ecm);
667}
668
669/*-------------------------------------------------------------------------*/
670
671/* ethernet function driver setup/binding */
672
673static int
674ecm_bind(struct usb_configuration *c, struct usb_function *f)
675{
676	struct usb_composite_dev *cdev = c->cdev;
677	struct f_ecm		*ecm = func_to_ecm(f);
 
678	int			status;
679	struct usb_ep		*ep;
680
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
681	/* allocate instance-specific interface IDs */
682	status = usb_interface_id(c, f);
683	if (status < 0)
684		goto fail;
685	ecm->ctrl_id = status;
 
686
687	ecm_control_intf.bInterfaceNumber = status;
688	ecm_union_desc.bMasterInterface0 = status;
689
690	status = usb_interface_id(c, f);
691	if (status < 0)
692		goto fail;
693	ecm->data_id = status;
694
695	ecm_data_nop_intf.bInterfaceNumber = status;
696	ecm_data_intf.bInterfaceNumber = status;
697	ecm_union_desc.bSlaveInterface0 = status;
698
699	status = -ENODEV;
700
701	/* allocate instance-specific endpoints */
702	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_in_desc);
703	if (!ep)
704		goto fail;
705	ecm->port.in_ep = ep;
706	ep->driver_data = cdev;	/* claim */
707
708	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_out_desc);
709	if (!ep)
710		goto fail;
711	ecm->port.out_ep = ep;
712	ep->driver_data = cdev;	/* claim */
713
714	/* NOTE:  a status/notification endpoint is *OPTIONAL* but we
715	 * don't treat it that way.  It's simpler, and some newer CDC
716	 * profiles (wireless handsets) no longer treat it as optional.
717	 */
718	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_notify_desc);
719	if (!ep)
720		goto fail;
721	ecm->notify = ep;
722	ep->driver_data = cdev;	/* claim */
723
724	status = -ENOMEM;
725
726	/* allocate notification request and buffer */
727	ecm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
728	if (!ecm->notify_req)
729		goto fail;
730	ecm->notify_req->buf = kmalloc(ECM_STATUS_BYTECOUNT, GFP_KERNEL);
731	if (!ecm->notify_req->buf)
732		goto fail;
733	ecm->notify_req->context = ecm;
734	ecm->notify_req->complete = ecm_notify_complete;
735
736	/* copy descriptors, and track endpoint copies */
737	f->descriptors = usb_copy_descriptors(ecm_fs_function);
738	if (!f->descriptors)
739		goto fail;
740
741	/* support all relevant hardware speeds... we expect that when
742	 * hardware is dual speed, all bulk-capable endpoints work at
743	 * both speeds
744	 */
745	if (gadget_is_dualspeed(c->cdev->gadget)) {
746		hs_ecm_in_desc.bEndpointAddress =
747				fs_ecm_in_desc.bEndpointAddress;
748		hs_ecm_out_desc.bEndpointAddress =
749				fs_ecm_out_desc.bEndpointAddress;
750		hs_ecm_notify_desc.bEndpointAddress =
751				fs_ecm_notify_desc.bEndpointAddress;
752
753		/* copy descriptors, and track endpoint copies */
754		f->hs_descriptors = usb_copy_descriptors(ecm_hs_function);
755		if (!f->hs_descriptors)
756			goto fail;
757	}
758
759	if (gadget_is_superspeed(c->cdev->gadget)) {
760		ss_ecm_in_desc.bEndpointAddress =
761				fs_ecm_in_desc.bEndpointAddress;
762		ss_ecm_out_desc.bEndpointAddress =
763				fs_ecm_out_desc.bEndpointAddress;
764		ss_ecm_notify_desc.bEndpointAddress =
765				fs_ecm_notify_desc.bEndpointAddress;
766
767		/* copy descriptors, and track endpoint copies */
768		f->ss_descriptors = usb_copy_descriptors(ecm_ss_function);
769		if (!f->ss_descriptors)
770			goto fail;
771	}
772
773	/* NOTE:  all that is done without knowing or caring about
774	 * the network link ... which is unavailable to this code
775	 * until we're activated via set_alt().
776	 */
777
778	ecm->port.open = ecm_open;
779	ecm->port.close = ecm_close;
780
781	DBG(cdev, "CDC Ethernet: %s speed IN/%s OUT/%s NOTIFY/%s\n",
782			gadget_is_superspeed(c->cdev->gadget) ? "super" :
783			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
784			ecm->port.in_ep->name, ecm->port.out_ep->name,
785			ecm->notify->name);
786	return 0;
787
788fail:
789	if (f->descriptors)
790		usb_free_descriptors(f->descriptors);
791	if (f->hs_descriptors)
792		usb_free_descriptors(f->hs_descriptors);
793
794	if (ecm->notify_req) {
795		kfree(ecm->notify_req->buf);
796		usb_ep_free_request(ecm->notify, ecm->notify_req);
797	}
798
799	/* we might as well release our claims on endpoints */
800	if (ecm->notify)
801		ecm->notify->driver_data = NULL;
802	if (ecm->port.out_ep->desc)
803		ecm->port.out_ep->driver_data = NULL;
804	if (ecm->port.in_ep->desc)
805		ecm->port.in_ep->driver_data = NULL;
806
807	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
808
809	return status;
810}
811
812static void
813ecm_unbind(struct usb_configuration *c, struct usb_function *f)
814{
815	struct f_ecm		*ecm = func_to_ecm(f);
 
 
816
817	DBG(c->cdev, "ecm unbind\n");
 
818
819	if (gadget_is_superspeed(c->cdev->gadget))
820		usb_free_descriptors(f->ss_descriptors);
821	if (gadget_is_dualspeed(c->cdev->gadget))
822		usb_free_descriptors(f->hs_descriptors);
823	usb_free_descriptors(f->descriptors);
824
825	kfree(ecm->notify_req->buf);
826	usb_ep_free_request(ecm->notify, ecm->notify_req);
827
828	ecm_string_defs[1].s = NULL;
829	kfree(ecm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
830}
831
832/**
833 * ecm_bind_config - add CDC Ethernet network link to a configuration
834 * @c: the configuration to support the network link
835 * @ethaddr: a buffer in which the ethernet address of the host side
836 *	side of the link was recorded
837 * Context: single threaded during gadget setup
838 *
839 * Returns zero on success, else negative errno.
840 *
841 * Caller must have called @gether_setup().  Caller is also responsible
842 * for calling @gether_cleanup() before module unload.
843 */
844int
845ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
846{
847	struct f_ecm	*ecm;
848	int		status;
849
850	if (!can_support_ecm(c->cdev->gadget) || !ethaddr)
851		return -EINVAL;
 
 
 
 
 
 
 
 
 
852
853	/* maybe allocate device-global string IDs */
854	if (ecm_string_defs[0].id == 0) {
855
856		/* control interface label */
857		status = usb_string_id(c->cdev);
858		if (status < 0)
859			return status;
860		ecm_string_defs[0].id = status;
861		ecm_control_intf.iInterface = status;
862
863		/* data interface label */
864		status = usb_string_id(c->cdev);
865		if (status < 0)
866			return status;
867		ecm_string_defs[2].id = status;
868		ecm_data_intf.iInterface = status;
869
870		/* MAC address */
871		status = usb_string_id(c->cdev);
872		if (status < 0)
873			return status;
874		ecm_string_defs[1].id = status;
875		ecm_desc.iMACAddress = status;
876	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
877
878	/* allocate and initialize one new instance */
879	ecm = kzalloc(sizeof *ecm, GFP_KERNEL);
880	if (!ecm)
881		return -ENOMEM;
 
 
 
 
882
883	/* export host's Ethernet address in CDC format */
884	snprintf(ecm->ethaddr, sizeof ecm->ethaddr,
885		"%02X%02X%02X%02X%02X%02X",
886		ethaddr[0], ethaddr[1], ethaddr[2],
887		ethaddr[3], ethaddr[4], ethaddr[5]);
 
 
 
888	ecm_string_defs[1].s = ecm->ethaddr;
889
 
 
890	ecm->port.cdc_filter = DEFAULT_FILTER;
891
892	ecm->port.func.name = "cdc_ethernet";
893	ecm->port.func.strings = ecm_strings;
894	/* descriptors are per-instance copies */
895	ecm->port.func.bind = ecm_bind;
896	ecm->port.func.unbind = ecm_unbind;
897	ecm->port.func.set_alt = ecm_set_alt;
898	ecm->port.func.get_alt = ecm_get_alt;
899	ecm->port.func.setup = ecm_setup;
900	ecm->port.func.disable = ecm_disable;
 
901
902	status = usb_add_function(c, &ecm->port.func);
903	if (status) {
904		ecm_string_defs[1].s = NULL;
905		kfree(ecm);
906	}
907	return status;
908}
v3.15
  1/*
  2 * f_ecm.c -- USB CDC Ethernet (ECM) link function driver
  3 *
  4 * Copyright (C) 2003-2005,2008 David Brownell
  5 * Copyright (C) 2008 Nokia Corporation
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 
 
 
 
 
 
 
 
 
 11 */
 12
 13/* #define VERBOSE_DEBUG */
 14
 15#include <linux/slab.h>
 16#include <linux/kernel.h>
 17#include <linux/module.h>
 18#include <linux/device.h>
 19#include <linux/etherdevice.h>
 20
 21#include "u_ether.h"
 22#include "u_ether_configfs.h"
 23#include "u_ecm.h"
 24
 25
 26/*
 27 * This function is a "CDC Ethernet Networking Control Model" (CDC ECM)
 28 * Ethernet link.  The data transfer model is simple (packets sent and
 29 * received over bulk endpoints using normal short packet termination),
 30 * and the control model exposes various data and optional notifications.
 31 *
 32 * ECM is well standardized and (except for Microsoft) supported by most
 33 * operating systems with USB host support.  It's the preferred interop
 34 * solution for Ethernet over USB, at least for firmware based solutions.
 35 * (Hardware solutions tend to be more minimalist.)  A newer and simpler
 36 * "Ethernet Emulation Model" (CDC EEM) hasn't yet caught on.
 37 *
 38 * Note that ECM requires the use of "alternate settings" for its data
 39 * interface.  This means that the set_alt() method has real work to do,
 40 * and also means that a get_alt() method is required.
 41 */
 42
 43
 44enum ecm_notify_state {
 45	ECM_NOTIFY_NONE,		/* don't notify */
 46	ECM_NOTIFY_CONNECT,		/* issue CONNECT next */
 47	ECM_NOTIFY_SPEED,		/* issue SPEED_CHANGE next */
 48};
 49
 50struct f_ecm {
 51	struct gether			port;
 52	u8				ctrl_id, data_id;
 53
 54	char				ethaddr[14];
 55
 56	struct usb_ep			*notify;
 57	struct usb_request		*notify_req;
 58	u8				notify_state;
 59	bool				is_open;
 60
 61	/* FIXME is_open needs some irq-ish locking
 62	 * ... possibly the same as port.ioport
 63	 */
 64};
 65
 66static inline struct f_ecm *func_to_ecm(struct usb_function *f)
 67{
 68	return container_of(f, struct f_ecm, port.func);
 69}
 70
 71/* peak (theoretical) bulk transfer rate in bits-per-second */
 72static inline unsigned ecm_bitrate(struct usb_gadget *g)
 73{
 74	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
 75		return 13 * 1024 * 8 * 1000 * 8;
 76	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 77		return 13 * 512 * 8 * 1000 * 8;
 78	else
 79		return 19 * 64 * 1 * 1000 * 8;
 80}
 81
 82/*-------------------------------------------------------------------------*/
 83
 84/*
 85 * Include the status endpoint if we can, even though it's optional.
 86 *
 87 * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 88 * packet, to simplify cancellation; and a big transfer interval, to
 89 * waste less bandwidth.
 90 *
 91 * Some drivers (like Linux 2.4 cdc-ether!) "need" it to exist even
 92 * if they ignore the connect/disconnect notifications that real aether
 93 * can provide.  More advanced cdc configurations might want to support
 94 * encapsulated commands (vendor-specific, using control-OUT).
 95 */
 96
 97#define ECM_STATUS_INTERVAL_MS		32
 98#define ECM_STATUS_BYTECOUNT		16	/* 8 byte header + data */
 99
100
101/* interface descriptor: */
102
103static struct usb_interface_assoc_descriptor
104ecm_iad_descriptor = {
105	.bLength =		sizeof ecm_iad_descriptor,
106	.bDescriptorType =	USB_DT_INTERFACE_ASSOCIATION,
107
108	/* .bFirstInterface =	DYNAMIC, */
109	.bInterfaceCount =	2,	/* control + data */
110	.bFunctionClass =	USB_CLASS_COMM,
111	.bFunctionSubClass =	USB_CDC_SUBCLASS_ETHERNET,
112	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
113	/* .iFunction =		DYNAMIC */
114};
115
116
117static struct usb_interface_descriptor ecm_control_intf = {
118	.bLength =		sizeof ecm_control_intf,
119	.bDescriptorType =	USB_DT_INTERFACE,
120
121	/* .bInterfaceNumber = DYNAMIC */
122	/* status endpoint is optional; this could be patched later */
123	.bNumEndpoints =	1,
124	.bInterfaceClass =	USB_CLASS_COMM,
125	.bInterfaceSubClass =	USB_CDC_SUBCLASS_ETHERNET,
126	.bInterfaceProtocol =	USB_CDC_PROTO_NONE,
127	/* .iInterface = DYNAMIC */
128};
129
130static struct usb_cdc_header_desc ecm_header_desc = {
131	.bLength =		sizeof ecm_header_desc,
132	.bDescriptorType =	USB_DT_CS_INTERFACE,
133	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
134
135	.bcdCDC =		cpu_to_le16(0x0110),
136};
137
138static struct usb_cdc_union_desc ecm_union_desc = {
139	.bLength =		sizeof(ecm_union_desc),
140	.bDescriptorType =	USB_DT_CS_INTERFACE,
141	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
142	/* .bMasterInterface0 =	DYNAMIC */
143	/* .bSlaveInterface0 =	DYNAMIC */
144};
145
146static struct usb_cdc_ether_desc ecm_desc = {
147	.bLength =		sizeof ecm_desc,
148	.bDescriptorType =	USB_DT_CS_INTERFACE,
149	.bDescriptorSubType =	USB_CDC_ETHERNET_TYPE,
150
151	/* this descriptor actually adds value, surprise! */
152	/* .iMACAddress = DYNAMIC */
153	.bmEthernetStatistics =	cpu_to_le32(0), /* no statistics */
154	.wMaxSegmentSize =	cpu_to_le16(ETH_FRAME_LEN),
155	.wNumberMCFilters =	cpu_to_le16(0),
156	.bNumberPowerFilters =	0,
157};
158
159/* the default data interface has no endpoints ... */
160
161static struct usb_interface_descriptor ecm_data_nop_intf = {
162	.bLength =		sizeof ecm_data_nop_intf,
163	.bDescriptorType =	USB_DT_INTERFACE,
164
165	.bInterfaceNumber =	1,
166	.bAlternateSetting =	0,
167	.bNumEndpoints =	0,
168	.bInterfaceClass =	USB_CLASS_CDC_DATA,
169	.bInterfaceSubClass =	0,
170	.bInterfaceProtocol =	0,
171	/* .iInterface = DYNAMIC */
172};
173
174/* ... but the "real" data interface has two bulk endpoints */
175
176static struct usb_interface_descriptor ecm_data_intf = {
177	.bLength =		sizeof ecm_data_intf,
178	.bDescriptorType =	USB_DT_INTERFACE,
179
180	.bInterfaceNumber =	1,
181	.bAlternateSetting =	1,
182	.bNumEndpoints =	2,
183	.bInterfaceClass =	USB_CLASS_CDC_DATA,
184	.bInterfaceSubClass =	0,
185	.bInterfaceProtocol =	0,
186	/* .iInterface = DYNAMIC */
187};
188
189/* full speed support: */
190
191static struct usb_endpoint_descriptor fs_ecm_notify_desc = {
192	.bLength =		USB_DT_ENDPOINT_SIZE,
193	.bDescriptorType =	USB_DT_ENDPOINT,
194
195	.bEndpointAddress =	USB_DIR_IN,
196	.bmAttributes =		USB_ENDPOINT_XFER_INT,
197	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
198	.bInterval =		ECM_STATUS_INTERVAL_MS,
199};
200
201static struct usb_endpoint_descriptor fs_ecm_in_desc = {
202	.bLength =		USB_DT_ENDPOINT_SIZE,
203	.bDescriptorType =	USB_DT_ENDPOINT,
204
205	.bEndpointAddress =	USB_DIR_IN,
206	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
207};
208
209static struct usb_endpoint_descriptor fs_ecm_out_desc = {
210	.bLength =		USB_DT_ENDPOINT_SIZE,
211	.bDescriptorType =	USB_DT_ENDPOINT,
212
213	.bEndpointAddress =	USB_DIR_OUT,
214	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
215};
216
217static struct usb_descriptor_header *ecm_fs_function[] = {
218	/* CDC ECM control descriptors */
219	(struct usb_descriptor_header *) &ecm_iad_descriptor,
220	(struct usb_descriptor_header *) &ecm_control_intf,
221	(struct usb_descriptor_header *) &ecm_header_desc,
222	(struct usb_descriptor_header *) &ecm_union_desc,
223	(struct usb_descriptor_header *) &ecm_desc,
224
225	/* NOTE: status endpoint might need to be removed */
226	(struct usb_descriptor_header *) &fs_ecm_notify_desc,
227
228	/* data interface, altsettings 0 and 1 */
229	(struct usb_descriptor_header *) &ecm_data_nop_intf,
230	(struct usb_descriptor_header *) &ecm_data_intf,
231	(struct usb_descriptor_header *) &fs_ecm_in_desc,
232	(struct usb_descriptor_header *) &fs_ecm_out_desc,
233	NULL,
234};
235
236/* high speed support: */
237
238static struct usb_endpoint_descriptor hs_ecm_notify_desc = {
239	.bLength =		USB_DT_ENDPOINT_SIZE,
240	.bDescriptorType =	USB_DT_ENDPOINT,
241
242	.bEndpointAddress =	USB_DIR_IN,
243	.bmAttributes =		USB_ENDPOINT_XFER_INT,
244	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
245	.bInterval =		USB_MS_TO_HS_INTERVAL(ECM_STATUS_INTERVAL_MS),
246};
247
248static struct usb_endpoint_descriptor hs_ecm_in_desc = {
249	.bLength =		USB_DT_ENDPOINT_SIZE,
250	.bDescriptorType =	USB_DT_ENDPOINT,
251
252	.bEndpointAddress =	USB_DIR_IN,
253	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
254	.wMaxPacketSize =	cpu_to_le16(512),
255};
256
257static struct usb_endpoint_descriptor hs_ecm_out_desc = {
258	.bLength =		USB_DT_ENDPOINT_SIZE,
259	.bDescriptorType =	USB_DT_ENDPOINT,
260
261	.bEndpointAddress =	USB_DIR_OUT,
262	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
263	.wMaxPacketSize =	cpu_to_le16(512),
264};
265
266static struct usb_descriptor_header *ecm_hs_function[] = {
267	/* CDC ECM control descriptors */
268	(struct usb_descriptor_header *) &ecm_iad_descriptor,
269	(struct usb_descriptor_header *) &ecm_control_intf,
270	(struct usb_descriptor_header *) &ecm_header_desc,
271	(struct usb_descriptor_header *) &ecm_union_desc,
272	(struct usb_descriptor_header *) &ecm_desc,
273
274	/* NOTE: status endpoint might need to be removed */
275	(struct usb_descriptor_header *) &hs_ecm_notify_desc,
276
277	/* data interface, altsettings 0 and 1 */
278	(struct usb_descriptor_header *) &ecm_data_nop_intf,
279	(struct usb_descriptor_header *) &ecm_data_intf,
280	(struct usb_descriptor_header *) &hs_ecm_in_desc,
281	(struct usb_descriptor_header *) &hs_ecm_out_desc,
282	NULL,
283};
284
285/* super speed support: */
286
287static struct usb_endpoint_descriptor ss_ecm_notify_desc = {
288	.bLength =		USB_DT_ENDPOINT_SIZE,
289	.bDescriptorType =	USB_DT_ENDPOINT,
290
291	.bEndpointAddress =	USB_DIR_IN,
292	.bmAttributes =		USB_ENDPOINT_XFER_INT,
293	.wMaxPacketSize =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
294	.bInterval =		USB_MS_TO_HS_INTERVAL(ECM_STATUS_INTERVAL_MS),
295};
296
297static struct usb_ss_ep_comp_descriptor ss_ecm_intr_comp_desc = {
298	.bLength =		sizeof ss_ecm_intr_comp_desc,
299	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
300
301	/* the following 3 values can be tweaked if necessary */
302	/* .bMaxBurst =		0, */
303	/* .bmAttributes =	0, */
304	.wBytesPerInterval =	cpu_to_le16(ECM_STATUS_BYTECOUNT),
305};
306
307static struct usb_endpoint_descriptor ss_ecm_in_desc = {
308	.bLength =		USB_DT_ENDPOINT_SIZE,
309	.bDescriptorType =	USB_DT_ENDPOINT,
310
311	.bEndpointAddress =	USB_DIR_IN,
312	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
313	.wMaxPacketSize =	cpu_to_le16(1024),
314};
315
316static struct usb_endpoint_descriptor ss_ecm_out_desc = {
317	.bLength =		USB_DT_ENDPOINT_SIZE,
318	.bDescriptorType =	USB_DT_ENDPOINT,
319
320	.bEndpointAddress =	USB_DIR_OUT,
321	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
322	.wMaxPacketSize =	cpu_to_le16(1024),
323};
324
325static struct usb_ss_ep_comp_descriptor ss_ecm_bulk_comp_desc = {
326	.bLength =		sizeof ss_ecm_bulk_comp_desc,
327	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
328
329	/* the following 2 values can be tweaked if necessary */
330	/* .bMaxBurst =		0, */
331	/* .bmAttributes =	0, */
332};
333
334static struct usb_descriptor_header *ecm_ss_function[] = {
335	/* CDC ECM control descriptors */
336	(struct usb_descriptor_header *) &ecm_iad_descriptor,
337	(struct usb_descriptor_header *) &ecm_control_intf,
338	(struct usb_descriptor_header *) &ecm_header_desc,
339	(struct usb_descriptor_header *) &ecm_union_desc,
340	(struct usb_descriptor_header *) &ecm_desc,
341
342	/* NOTE: status endpoint might need to be removed */
343	(struct usb_descriptor_header *) &ss_ecm_notify_desc,
344	(struct usb_descriptor_header *) &ss_ecm_intr_comp_desc,
345
346	/* data interface, altsettings 0 and 1 */
347	(struct usb_descriptor_header *) &ecm_data_nop_intf,
348	(struct usb_descriptor_header *) &ecm_data_intf,
349	(struct usb_descriptor_header *) &ss_ecm_in_desc,
350	(struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
351	(struct usb_descriptor_header *) &ss_ecm_out_desc,
352	(struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
353	NULL,
354};
355
356/* string descriptors: */
357
358static struct usb_string ecm_string_defs[] = {
359	[0].s = "CDC Ethernet Control Model (ECM)",
360	[1].s = "",
361	[2].s = "CDC Ethernet Data",
362	[3].s = "CDC ECM",
363	{  } /* end of list */
364};
365
366static struct usb_gadget_strings ecm_string_table = {
367	.language =		0x0409,	/* en-us */
368	.strings =		ecm_string_defs,
369};
370
371static struct usb_gadget_strings *ecm_strings[] = {
372	&ecm_string_table,
373	NULL,
374};
375
376/*-------------------------------------------------------------------------*/
377
378static void ecm_do_notify(struct f_ecm *ecm)
379{
380	struct usb_request		*req = ecm->notify_req;
381	struct usb_cdc_notification	*event;
382	struct usb_composite_dev	*cdev = ecm->port.func.config->cdev;
383	__le32				*data;
384	int				status;
385
386	/* notification already in flight? */
387	if (!req)
388		return;
389
390	event = req->buf;
391	switch (ecm->notify_state) {
392	case ECM_NOTIFY_NONE:
393		return;
394
395	case ECM_NOTIFY_CONNECT:
396		event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
397		if (ecm->is_open)
398			event->wValue = cpu_to_le16(1);
399		else
400			event->wValue = cpu_to_le16(0);
401		event->wLength = 0;
402		req->length = sizeof *event;
403
404		DBG(cdev, "notify connect %s\n",
405				ecm->is_open ? "true" : "false");
406		ecm->notify_state = ECM_NOTIFY_SPEED;
407		break;
408
409	case ECM_NOTIFY_SPEED:
410		event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
411		event->wValue = cpu_to_le16(0);
412		event->wLength = cpu_to_le16(8);
413		req->length = ECM_STATUS_BYTECOUNT;
414
415		/* SPEED_CHANGE data is up/down speeds in bits/sec */
416		data = req->buf + sizeof *event;
417		data[0] = cpu_to_le32(ecm_bitrate(cdev->gadget));
418		data[1] = data[0];
419
420		DBG(cdev, "notify speed %d\n", ecm_bitrate(cdev->gadget));
421		ecm->notify_state = ECM_NOTIFY_NONE;
422		break;
423	}
424	event->bmRequestType = 0xA1;
425	event->wIndex = cpu_to_le16(ecm->ctrl_id);
426
427	ecm->notify_req = NULL;
428	status = usb_ep_queue(ecm->notify, req, GFP_ATOMIC);
429	if (status < 0) {
430		ecm->notify_req = req;
431		DBG(cdev, "notify --> %d\n", status);
432	}
433}
434
435static void ecm_notify(struct f_ecm *ecm)
436{
437	/* NOTE on most versions of Linux, host side cdc-ethernet
438	 * won't listen for notifications until its netdevice opens.
439	 * The first notification then sits in the FIFO for a long
440	 * time, and the second one is queued.
441	 */
442	ecm->notify_state = ECM_NOTIFY_CONNECT;
443	ecm_do_notify(ecm);
444}
445
446static void ecm_notify_complete(struct usb_ep *ep, struct usb_request *req)
447{
448	struct f_ecm			*ecm = req->context;
449	struct usb_composite_dev	*cdev = ecm->port.func.config->cdev;
450	struct usb_cdc_notification	*event = req->buf;
451
452	switch (req->status) {
453	case 0:
454		/* no fault */
455		break;
456	case -ECONNRESET:
457	case -ESHUTDOWN:
458		ecm->notify_state = ECM_NOTIFY_NONE;
459		break;
460	default:
461		DBG(cdev, "event %02x --> %d\n",
462			event->bNotificationType, req->status);
463		break;
464	}
465	ecm->notify_req = req;
466	ecm_do_notify(ecm);
467}
468
469static int ecm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
470{
471	struct f_ecm		*ecm = func_to_ecm(f);
472	struct usb_composite_dev *cdev = f->config->cdev;
473	struct usb_request	*req = cdev->req;
474	int			value = -EOPNOTSUPP;
475	u16			w_index = le16_to_cpu(ctrl->wIndex);
476	u16			w_value = le16_to_cpu(ctrl->wValue);
477	u16			w_length = le16_to_cpu(ctrl->wLength);
478
479	/* composite driver infrastructure handles everything except
480	 * CDC class messages; interface activation uses set_alt().
481	 */
482	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
483	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
484			| USB_CDC_SET_ETHERNET_PACKET_FILTER:
485		/* see 6.2.30: no data, wIndex = interface,
486		 * wValue = packet filter bitmap
487		 */
488		if (w_length != 0 || w_index != ecm->ctrl_id)
489			goto invalid;
490		DBG(cdev, "packet filter %02x\n", w_value);
491		/* REVISIT locking of cdc_filter.  This assumes the UDC
492		 * driver won't have a concurrent packet TX irq running on
493		 * another CPU; or that if it does, this write is atomic...
494		 */
495		ecm->port.cdc_filter = w_value;
496		value = 0;
497		break;
498
499	/* and optionally:
500	 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
501	 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
502	 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
503	 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
504	 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
505	 * case USB_CDC_GET_ETHERNET_STATISTIC:
506	 */
507
508	default:
509invalid:
510		DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
511			ctrl->bRequestType, ctrl->bRequest,
512			w_value, w_index, w_length);
513	}
514
515	/* respond with data transfer or status phase? */
516	if (value >= 0) {
517		DBG(cdev, "ecm req%02x.%02x v%04x i%04x l%d\n",
518			ctrl->bRequestType, ctrl->bRequest,
519			w_value, w_index, w_length);
520		req->zero = 0;
521		req->length = value;
522		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
523		if (value < 0)
524			ERROR(cdev, "ecm req %02x.%02x response err %d\n",
525					ctrl->bRequestType, ctrl->bRequest,
526					value);
527	}
528
529	/* device either stalls (value < 0) or reports success */
530	return value;
531}
532
533
534static int ecm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
535{
536	struct f_ecm		*ecm = func_to_ecm(f);
537	struct usb_composite_dev *cdev = f->config->cdev;
538
539	/* Control interface has only altsetting 0 */
540	if (intf == ecm->ctrl_id) {
541		if (alt != 0)
542			goto fail;
543
544		if (ecm->notify->driver_data) {
545			VDBG(cdev, "reset ecm control %d\n", intf);
546			usb_ep_disable(ecm->notify);
547		}
548		if (!(ecm->notify->desc)) {
549			VDBG(cdev, "init ecm ctrl %d\n", intf);
550			if (config_ep_by_speed(cdev->gadget, f, ecm->notify))
551				goto fail;
552		}
553		usb_ep_enable(ecm->notify);
554		ecm->notify->driver_data = ecm;
555
556	/* Data interface has two altsettings, 0 and 1 */
557	} else if (intf == ecm->data_id) {
558		if (alt > 1)
559			goto fail;
560
561		if (ecm->port.in_ep->driver_data) {
562			DBG(cdev, "reset ecm\n");
563			gether_disconnect(&ecm->port);
564		}
565
566		if (!ecm->port.in_ep->desc ||
567		    !ecm->port.out_ep->desc) {
568			DBG(cdev, "init ecm\n");
569			if (config_ep_by_speed(cdev->gadget, f,
570					       ecm->port.in_ep) ||
571			    config_ep_by_speed(cdev->gadget, f,
572					       ecm->port.out_ep)) {
573				ecm->port.in_ep->desc = NULL;
574				ecm->port.out_ep->desc = NULL;
575				goto fail;
576			}
577		}
578
579		/* CDC Ethernet only sends data in non-default altsettings.
580		 * Changing altsettings resets filters, statistics, etc.
581		 */
582		if (alt == 1) {
583			struct net_device	*net;
584
585			/* Enable zlps by default for ECM conformance;
586			 * override for musb_hdrc (avoids txdma ovhead).
587			 */
588			ecm->port.is_zlp_ok = !(gadget_is_musbhdrc(cdev->gadget)
589				);
590			ecm->port.cdc_filter = DEFAULT_FILTER;
591			DBG(cdev, "activate ecm\n");
592			net = gether_connect(&ecm->port);
593			if (IS_ERR(net))
594				return PTR_ERR(net);
595		}
596
597		/* NOTE this can be a minor disagreement with the ECM spec,
598		 * which says speed notifications will "always" follow
599		 * connection notifications.  But we allow one connect to
600		 * follow another (if the first is in flight), and instead
601		 * just guarantee that a speed notification is always sent.
602		 */
603		ecm_notify(ecm);
604	} else
605		goto fail;
606
607	return 0;
608fail:
609	return -EINVAL;
610}
611
612/* Because the data interface supports multiple altsettings,
613 * this ECM function *MUST* implement a get_alt() method.
614 */
615static int ecm_get_alt(struct usb_function *f, unsigned intf)
616{
617	struct f_ecm		*ecm = func_to_ecm(f);
618
619	if (intf == ecm->ctrl_id)
620		return 0;
621	return ecm->port.in_ep->driver_data ? 1 : 0;
622}
623
624static void ecm_disable(struct usb_function *f)
625{
626	struct f_ecm		*ecm = func_to_ecm(f);
627	struct usb_composite_dev *cdev = f->config->cdev;
628
629	DBG(cdev, "ecm deactivated\n");
630
631	if (ecm->port.in_ep->driver_data)
632		gether_disconnect(&ecm->port);
633
634	if (ecm->notify->driver_data) {
635		usb_ep_disable(ecm->notify);
636		ecm->notify->driver_data = NULL;
637		ecm->notify->desc = NULL;
638	}
639}
640
641/*-------------------------------------------------------------------------*/
642
643/*
644 * Callbacks let us notify the host about connect/disconnect when the
645 * net device is opened or closed.
646 *
647 * For testing, note that link states on this side include both opened
648 * and closed variants of:
649 *
650 *   - disconnected/unconfigured
651 *   - configured but inactive (data alt 0)
652 *   - configured and active (data alt 1)
653 *
654 * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
655 * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
656 * imply the host is actually polling the notification endpoint, and
657 * likewise that "active" doesn't imply it's actually using the data
658 * endpoints for traffic.
659 */
660
661static void ecm_open(struct gether *geth)
662{
663	struct f_ecm		*ecm = func_to_ecm(&geth->func);
664
665	DBG(ecm->port.func.config->cdev, "%s\n", __func__);
666
667	ecm->is_open = true;
668	ecm_notify(ecm);
669}
670
671static void ecm_close(struct gether *geth)
672{
673	struct f_ecm		*ecm = func_to_ecm(&geth->func);
674
675	DBG(ecm->port.func.config->cdev, "%s\n", __func__);
676
677	ecm->is_open = false;
678	ecm_notify(ecm);
679}
680
681/*-------------------------------------------------------------------------*/
682
683/* ethernet function driver setup/binding */
684
685static int
686ecm_bind(struct usb_configuration *c, struct usb_function *f)
687{
688	struct usb_composite_dev *cdev = c->cdev;
689	struct f_ecm		*ecm = func_to_ecm(f);
690	struct usb_string	*us;
691	int			status;
692	struct usb_ep		*ep;
693
694	struct f_ecm_opts	*ecm_opts;
695
696	if (!can_support_ecm(cdev->gadget))
697		return -EINVAL;
698
699	ecm_opts = container_of(f->fi, struct f_ecm_opts, func_inst);
700
701	/*
702	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
703	 * configurations are bound in sequence with list_for_each_entry,
704	 * in each configuration its functions are bound in sequence
705	 * with list_for_each_entry, so we assume no race condition
706	 * with regard to ecm_opts->bound access
707	 */
708	if (!ecm_opts->bound) {
709		mutex_lock(&ecm_opts->lock);
710		gether_set_gadget(ecm_opts->net, cdev->gadget);
711		status = gether_register_netdev(ecm_opts->net);
712		mutex_unlock(&ecm_opts->lock);
713		if (status)
714			return status;
715		ecm_opts->bound = true;
716	}
717
718	us = usb_gstrings_attach(cdev, ecm_strings,
719				 ARRAY_SIZE(ecm_string_defs));
720	if (IS_ERR(us))
721		return PTR_ERR(us);
722	ecm_control_intf.iInterface = us[0].id;
723	ecm_data_intf.iInterface = us[2].id;
724	ecm_desc.iMACAddress = us[1].id;
725	ecm_iad_descriptor.iFunction = us[3].id;
726
727	/* allocate instance-specific interface IDs */
728	status = usb_interface_id(c, f);
729	if (status < 0)
730		goto fail;
731	ecm->ctrl_id = status;
732	ecm_iad_descriptor.bFirstInterface = status;
733
734	ecm_control_intf.bInterfaceNumber = status;
735	ecm_union_desc.bMasterInterface0 = status;
736
737	status = usb_interface_id(c, f);
738	if (status < 0)
739		goto fail;
740	ecm->data_id = status;
741
742	ecm_data_nop_intf.bInterfaceNumber = status;
743	ecm_data_intf.bInterfaceNumber = status;
744	ecm_union_desc.bSlaveInterface0 = status;
745
746	status = -ENODEV;
747
748	/* allocate instance-specific endpoints */
749	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_in_desc);
750	if (!ep)
751		goto fail;
752	ecm->port.in_ep = ep;
753	ep->driver_data = cdev;	/* claim */
754
755	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_out_desc);
756	if (!ep)
757		goto fail;
758	ecm->port.out_ep = ep;
759	ep->driver_data = cdev;	/* claim */
760
761	/* NOTE:  a status/notification endpoint is *OPTIONAL* but we
762	 * don't treat it that way.  It's simpler, and some newer CDC
763	 * profiles (wireless handsets) no longer treat it as optional.
764	 */
765	ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_notify_desc);
766	if (!ep)
767		goto fail;
768	ecm->notify = ep;
769	ep->driver_data = cdev;	/* claim */
770
771	status = -ENOMEM;
772
773	/* allocate notification request and buffer */
774	ecm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
775	if (!ecm->notify_req)
776		goto fail;
777	ecm->notify_req->buf = kmalloc(ECM_STATUS_BYTECOUNT, GFP_KERNEL);
778	if (!ecm->notify_req->buf)
779		goto fail;
780	ecm->notify_req->context = ecm;
781	ecm->notify_req->complete = ecm_notify_complete;
782
 
 
 
 
 
783	/* support all relevant hardware speeds... we expect that when
784	 * hardware is dual speed, all bulk-capable endpoints work at
785	 * both speeds
786	 */
787	hs_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
788	hs_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
789	hs_ecm_notify_desc.bEndpointAddress =
790		fs_ecm_notify_desc.bEndpointAddress;
791
792	ss_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
793	ss_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
794	ss_ecm_notify_desc.bEndpointAddress =
795		fs_ecm_notify_desc.bEndpointAddress;
796
797	status = usb_assign_descriptors(f, ecm_fs_function, ecm_hs_function,
798			ecm_ss_function);
799	if (status)
800		goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
801
802	/* NOTE:  all that is done without knowing or caring about
803	 * the network link ... which is unavailable to this code
804	 * until we're activated via set_alt().
805	 */
806
807	ecm->port.open = ecm_open;
808	ecm->port.close = ecm_close;
809
810	DBG(cdev, "CDC Ethernet: %s speed IN/%s OUT/%s NOTIFY/%s\n",
811			gadget_is_superspeed(c->cdev->gadget) ? "super" :
812			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
813			ecm->port.in_ep->name, ecm->port.out_ep->name,
814			ecm->notify->name);
815	return 0;
816
817fail:
 
 
 
 
 
818	if (ecm->notify_req) {
819		kfree(ecm->notify_req->buf);
820		usb_ep_free_request(ecm->notify, ecm->notify_req);
821	}
822
823	/* we might as well release our claims on endpoints */
824	if (ecm->notify)
825		ecm->notify->driver_data = NULL;
826	if (ecm->port.out_ep)
827		ecm->port.out_ep->driver_data = NULL;
828	if (ecm->port.in_ep)
829		ecm->port.in_ep->driver_data = NULL;
830
831	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
832
833	return status;
834}
835
836static inline struct f_ecm_opts *to_f_ecm_opts(struct config_item *item)
 
837{
838	return container_of(to_config_group(item), struct f_ecm_opts,
839			    func_inst.group);
840}
841
842/* f_ecm_item_ops */
843USB_ETHERNET_CONFIGFS_ITEM(ecm);
844
845/* f_ecm_opts_dev_addr */
846USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ecm);
 
 
 
847
848/* f_ecm_opts_host_addr */
849USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ecm);
850
851/* f_ecm_opts_qmult */
852USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ecm);
853
854/* f_ecm_opts_ifname */
855USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ecm);
856
857static struct configfs_attribute *ecm_attrs[] = {
858	&f_ecm_opts_dev_addr.attr,
859	&f_ecm_opts_host_addr.attr,
860	&f_ecm_opts_qmult.attr,
861	&f_ecm_opts_ifname.attr,
862	NULL,
863};
864
865static struct config_item_type ecm_func_type = {
866	.ct_item_ops	= &ecm_item_ops,
867	.ct_attrs	= ecm_attrs,
868	.ct_owner	= THIS_MODULE,
869};
870
871static void ecm_free_inst(struct usb_function_instance *f)
872{
873	struct f_ecm_opts *opts;
874
875	opts = container_of(f, struct f_ecm_opts, func_inst);
876	if (opts->bound)
877		gether_cleanup(netdev_priv(opts->net));
878	else
879		free_netdev(opts->net);
880	kfree(opts);
881}
882
883static struct usb_function_instance *ecm_alloc_inst(void)
 
 
 
 
 
 
 
 
 
 
 
 
 
884{
885	struct f_ecm_opts *opts;
 
886
887	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
888	if (!opts)
889		return ERR_PTR(-ENOMEM);
890	mutex_init(&opts->lock);
891	opts->func_inst.free_func_inst = ecm_free_inst;
892	opts->net = gether_setup_default();
893	if (IS_ERR(opts->net)) {
894		struct net_device *net = opts->net;
895		kfree(opts);
896		return ERR_CAST(net);
897	}
898
899	config_group_init_type_name(&opts->func_inst.group, "", &ecm_func_type);
 
900
901	return &opts->func_inst;
902}
 
 
 
 
903
904static void ecm_free(struct usb_function *f)
905{
906	struct f_ecm *ecm;
907	struct f_ecm_opts *opts;
 
 
908
909	ecm = func_to_ecm(f);
910	opts = container_of(f->fi, struct f_ecm_opts, func_inst);
911	kfree(ecm);
912	mutex_lock(&opts->lock);
913	opts->refcnt--;
914	mutex_unlock(&opts->lock);
915}
916
917static void ecm_unbind(struct usb_configuration *c, struct usb_function *f)
918{
919	struct f_ecm		*ecm = func_to_ecm(f);
920
921	DBG(c->cdev, "ecm unbind\n");
922
923	usb_free_all_descriptors(f);
924
925	kfree(ecm->notify_req->buf);
926	usb_ep_free_request(ecm->notify, ecm->notify_req);
927}
928
929static struct usb_function *ecm_alloc(struct usb_function_instance *fi)
930{
931	struct f_ecm	*ecm;
932	struct f_ecm_opts *opts;
933	int status;
934
935	/* allocate and initialize one new instance */
936	ecm = kzalloc(sizeof(*ecm), GFP_KERNEL);
937	if (!ecm)
938		return ERR_PTR(-ENOMEM);
939
940	opts = container_of(fi, struct f_ecm_opts, func_inst);
941	mutex_lock(&opts->lock);
942	opts->refcnt++;
943
944	/* export host's Ethernet address in CDC format */
945	status = gether_get_host_addr_cdc(opts->net, ecm->ethaddr,
946					  sizeof(ecm->ethaddr));
947	if (status < 12) {
948		kfree(ecm);
949		mutex_unlock(&opts->lock);
950		return ERR_PTR(-EINVAL);
951	}
952	ecm_string_defs[1].s = ecm->ethaddr;
953
954	ecm->port.ioport = netdev_priv(opts->net);
955	mutex_unlock(&opts->lock);
956	ecm->port.cdc_filter = DEFAULT_FILTER;
957
958	ecm->port.func.name = "cdc_ethernet";
 
959	/* descriptors are per-instance copies */
960	ecm->port.func.bind = ecm_bind;
961	ecm->port.func.unbind = ecm_unbind;
962	ecm->port.func.set_alt = ecm_set_alt;
963	ecm->port.func.get_alt = ecm_get_alt;
964	ecm->port.func.setup = ecm_setup;
965	ecm->port.func.disable = ecm_disable;
966	ecm->port.func.free_func = ecm_free;
967
968	return &ecm->port.func;
 
 
 
 
 
969}
970
971DECLARE_USB_FUNCTION_INIT(ecm, ecm_alloc_inst, ecm_alloc);
972MODULE_LICENSE("GPL");
973MODULE_AUTHOR("David Brownell");