xref: /openbmc/linux/drivers/net/usb/cdc_ether.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * CDC Ethernet based networking peripherals
3  * Copyright (C) 2003-2005 by David Brownell
4  * Copyright (C) 2006 by Ole Andre Vadla Ravnas (ActiveSync)
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 // #define	DEBUG			// error path messages, extra info
22 // #define	VERBOSE			// more; success messages
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
28 #include <linux/ethtool.h>
29 #include <linux/workqueue.h>
30 #include <linux/mii.h>
31 #include <linux/usb.h>
32 #include <linux/usb/cdc.h>
33 #include <linux/usb/usbnet.h>
34 
35 
36 #if defined(CONFIG_USB_NET_RNDIS_HOST) || defined(CONFIG_USB_NET_RNDIS_HOST_MODULE)
37 
38 static int is_rndis(struct usb_interface_descriptor *desc)
39 {
40 	return (desc->bInterfaceClass == USB_CLASS_COMM &&
41 		desc->bInterfaceSubClass == 2 &&
42 		desc->bInterfaceProtocol == 0xff);
43 }
44 
45 static int is_activesync(struct usb_interface_descriptor *desc)
46 {
47 	return (desc->bInterfaceClass == USB_CLASS_MISC &&
48 		desc->bInterfaceSubClass == 1 &&
49 		desc->bInterfaceProtocol == 1);
50 }
51 
52 static int is_wireless_rndis(struct usb_interface_descriptor *desc)
53 {
54 	return (desc->bInterfaceClass == USB_CLASS_WIRELESS_CONTROLLER &&
55 		desc->bInterfaceSubClass == 1 &&
56 		desc->bInterfaceProtocol == 3);
57 }
58 
59 #else
60 
61 #define is_rndis(desc)		0
62 #define is_activesync(desc)	0
63 #define is_wireless_rndis(desc)	0
64 
65 #endif
66 
67 static const u8 mbm_guid[16] = {
68 	0xa3, 0x17, 0xa8, 0x8b, 0x04, 0x5e, 0x4f, 0x01,
69 	0xa6, 0x07, 0xc0, 0xff, 0xcb, 0x7e, 0x39, 0x2a,
70 };
71 
72 /*
73  * probes control interface, claims data interface, collects the bulk
74  * endpoints, activates data interface (if needed), maybe sets MTU.
75  * all pure cdc, except for certain firmware workarounds, and knowing
76  * that rndis uses one different rule.
77  */
78 int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
79 {
80 	u8				*buf = intf->cur_altsetting->extra;
81 	int				len = intf->cur_altsetting->extralen;
82 	struct usb_interface_descriptor	*d;
83 	struct cdc_state		*info = (void *) &dev->data;
84 	int				status;
85 	int				rndis;
86 	struct usb_driver		*driver = driver_of(intf);
87 	struct usb_cdc_mdlm_desc	*desc = NULL;
88 	struct usb_cdc_mdlm_detail_desc *detail = NULL;
89 
90 	if (sizeof dev->data < sizeof *info)
91 		return -EDOM;
92 
93 	/* expect strict spec conformance for the descriptors, but
94 	 * cope with firmware which stores them in the wrong place
95 	 */
96 	if (len == 0 && dev->udev->actconfig->extralen) {
97 		/* Motorola SB4100 (and others: Brad Hards says it's
98 		 * from a Broadcom design) put CDC descriptors here
99 		 */
100 		buf = dev->udev->actconfig->extra;
101 		len = dev->udev->actconfig->extralen;
102 		dev_dbg(&intf->dev, "CDC descriptors on config\n");
103 	}
104 
105 	/* Maybe CDC descriptors are after the endpoint?  This bug has
106 	 * been seen on some 2Wire Inc RNDIS-ish products.
107 	 */
108 	if (len == 0) {
109 		struct usb_host_endpoint	*hep;
110 
111 		hep = intf->cur_altsetting->endpoint;
112 		if (hep) {
113 			buf = hep->extra;
114 			len = hep->extralen;
115 		}
116 		if (len)
117 			dev_dbg(&intf->dev,
118 				"CDC descriptors on endpoint\n");
119 	}
120 
121 	/* this assumes that if there's a non-RNDIS vendor variant
122 	 * of cdc-acm, it'll fail RNDIS requests cleanly.
123 	 */
124 	rndis = (is_rndis(&intf->cur_altsetting->desc) ||
125 		 is_activesync(&intf->cur_altsetting->desc) ||
126 		 is_wireless_rndis(&intf->cur_altsetting->desc));
127 
128 	memset(info, 0, sizeof *info);
129 	info->control = intf;
130 	while (len > 3) {
131 		if (buf [1] != USB_DT_CS_INTERFACE)
132 			goto next_desc;
133 
134 		/* use bDescriptorSubType to identify the CDC descriptors.
135 		 * We expect devices with CDC header and union descriptors.
136 		 * For CDC Ethernet we need the ethernet descriptor.
137 		 * For RNDIS, ignore two (pointless) CDC modem descriptors
138 		 * in favor of a complicated OID-based RPC scheme doing what
139 		 * CDC Ethernet achieves with a simple descriptor.
140 		 */
141 		switch (buf [2]) {
142 		case USB_CDC_HEADER_TYPE:
143 			if (info->header) {
144 				dev_dbg(&intf->dev, "extra CDC header\n");
145 				goto bad_desc;
146 			}
147 			info->header = (void *) buf;
148 			if (info->header->bLength != sizeof *info->header) {
149 				dev_dbg(&intf->dev, "CDC header len %u\n",
150 					info->header->bLength);
151 				goto bad_desc;
152 			}
153 			break;
154 		case USB_CDC_ACM_TYPE:
155 			/* paranoia:  disambiguate a "real" vendor-specific
156 			 * modem interface from an RNDIS non-modem.
157 			 */
158 			if (rndis) {
159 				struct usb_cdc_acm_descriptor *acm;
160 
161 				acm = (void *) buf;
162 				if (acm->bmCapabilities) {
163 					dev_dbg(&intf->dev,
164 						"ACM capabilities %02x, "
165 						"not really RNDIS?\n",
166 						acm->bmCapabilities);
167 					goto bad_desc;
168 				}
169 			}
170 			break;
171 		case USB_CDC_UNION_TYPE:
172 			if (info->u) {
173 				dev_dbg(&intf->dev, "extra CDC union\n");
174 				goto bad_desc;
175 			}
176 			info->u = (void *) buf;
177 			if (info->u->bLength != sizeof *info->u) {
178 				dev_dbg(&intf->dev, "CDC union len %u\n",
179 					info->u->bLength);
180 				goto bad_desc;
181 			}
182 
183 			/* we need a master/control interface (what we're
184 			 * probed with) and a slave/data interface; union
185 			 * descriptors sort this all out.
186 			 */
187 			info->control = usb_ifnum_to_if(dev->udev,
188 						info->u->bMasterInterface0);
189 			info->data = usb_ifnum_to_if(dev->udev,
190 						info->u->bSlaveInterface0);
191 			if (!info->control || !info->data) {
192 				dev_dbg(&intf->dev,
193 					"master #%u/%p slave #%u/%p\n",
194 					info->u->bMasterInterface0,
195 					info->control,
196 					info->u->bSlaveInterface0,
197 					info->data);
198 				goto bad_desc;
199 			}
200 			if (info->control != intf) {
201 				dev_dbg(&intf->dev, "bogus CDC Union\n");
202 				/* Ambit USB Cable Modem (and maybe others)
203 				 * interchanges master and slave interface.
204 				 */
205 				if (info->data == intf) {
206 					info->data = info->control;
207 					info->control = intf;
208 				} else
209 					goto bad_desc;
210 			}
211 
212 			/* a data interface altsetting does the real i/o */
213 			d = &info->data->cur_altsetting->desc;
214 			if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
215 				dev_dbg(&intf->dev, "slave class %u\n",
216 					d->bInterfaceClass);
217 				goto bad_desc;
218 			}
219 			break;
220 		case USB_CDC_ETHERNET_TYPE:
221 			if (info->ether) {
222 				dev_dbg(&intf->dev, "extra CDC ether\n");
223 				goto bad_desc;
224 			}
225 			info->ether = (void *) buf;
226 			if (info->ether->bLength != sizeof *info->ether) {
227 				dev_dbg(&intf->dev, "CDC ether len %u\n",
228 					info->ether->bLength);
229 				goto bad_desc;
230 			}
231 			dev->hard_mtu = le16_to_cpu(
232 						info->ether->wMaxSegmentSize);
233 			/* because of Zaurus, we may be ignoring the host
234 			 * side link address we were given.
235 			 */
236 			break;
237 		case USB_CDC_MDLM_TYPE:
238 			if (desc) {
239 				dev_dbg(&intf->dev, "extra MDLM descriptor\n");
240 				goto bad_desc;
241 			}
242 
243 			desc = (void *)buf;
244 
245 			if (desc->bLength != sizeof(*desc))
246 				goto bad_desc;
247 
248 			if (memcmp(&desc->bGUID, mbm_guid, 16))
249 				goto bad_desc;
250 			break;
251 		case USB_CDC_MDLM_DETAIL_TYPE:
252 			if (detail) {
253 				dev_dbg(&intf->dev, "extra MDLM detail descriptor\n");
254 				goto bad_desc;
255 			}
256 
257 			detail = (void *)buf;
258 
259 			if (detail->bGuidDescriptorType == 0) {
260 				if (detail->bLength < (sizeof(*detail) + 1))
261 					goto bad_desc;
262 			} else
263 				goto bad_desc;
264 			break;
265 		}
266 next_desc:
267 		len -= buf [0];	/* bLength */
268 		buf += buf [0];
269 	}
270 
271 	/* Microsoft ActiveSync based and some regular RNDIS devices lack the
272 	 * CDC descriptors, so we'll hard-wire the interfaces and not check
273 	 * for descriptors.
274 	 */
275 	if (rndis && !info->u) {
276 		info->control = usb_ifnum_to_if(dev->udev, 0);
277 		info->data = usb_ifnum_to_if(dev->udev, 1);
278 		if (!info->control || !info->data) {
279 			dev_dbg(&intf->dev,
280 				"rndis: master #0/%p slave #1/%p\n",
281 				info->control,
282 				info->data);
283 			goto bad_desc;
284 		}
285 
286 	} else if (!info->header || !info->u || (!rndis && !info->ether)) {
287 		dev_dbg(&intf->dev, "missing cdc %s%s%sdescriptor\n",
288 			info->header ? "" : "header ",
289 			info->u ? "" : "union ",
290 			info->ether ? "" : "ether ");
291 		goto bad_desc;
292 	}
293 
294 	/* claim data interface and set it up ... with side effects.
295 	 * network traffic can't flow until an altsetting is enabled.
296 	 */
297 	status = usb_driver_claim_interface(driver, info->data, dev);
298 	if (status < 0)
299 		return status;
300 	status = usbnet_get_endpoints(dev, info->data);
301 	if (status < 0) {
302 		/* ensure immediate exit from usbnet_disconnect */
303 		usb_set_intfdata(info->data, NULL);
304 		usb_driver_release_interface(driver, info->data);
305 		return status;
306 	}
307 
308 	/* status endpoint: optional for CDC Ethernet, not RNDIS (or ACM) */
309 	dev->status = NULL;
310 	if (info->control->cur_altsetting->desc.bNumEndpoints == 1) {
311 		struct usb_endpoint_descriptor	*desc;
312 
313 		dev->status = &info->control->cur_altsetting->endpoint [0];
314 		desc = &dev->status->desc;
315 		if (!usb_endpoint_is_int_in(desc) ||
316 		    (le16_to_cpu(desc->wMaxPacketSize)
317 		     < sizeof(struct usb_cdc_notification)) ||
318 		    !desc->bInterval) {
319 			dev_dbg(&intf->dev, "bad notification endpoint\n");
320 			dev->status = NULL;
321 		}
322 	}
323 	if (rndis && !dev->status) {
324 		dev_dbg(&intf->dev, "missing RNDIS status endpoint\n");
325 		usb_set_intfdata(info->data, NULL);
326 		usb_driver_release_interface(driver, info->data);
327 		return -ENODEV;
328 	}
329 	return 0;
330 
331 bad_desc:
332 	dev_info(&dev->udev->dev, "bad CDC descriptors\n");
333 	return -ENODEV;
334 }
335 EXPORT_SYMBOL_GPL(usbnet_generic_cdc_bind);
336 
337 void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
338 {
339 	struct cdc_state		*info = (void *) &dev->data;
340 	struct usb_driver		*driver = driver_of(intf);
341 
342 	/* disconnect master --> disconnect slave */
343 	if (intf == info->control && info->data) {
344 		/* ensure immediate exit from usbnet_disconnect */
345 		usb_set_intfdata(info->data, NULL);
346 		usb_driver_release_interface(driver, info->data);
347 		info->data = NULL;
348 	}
349 
350 	/* and vice versa (just in case) */
351 	else if (intf == info->data && info->control) {
352 		/* ensure immediate exit from usbnet_disconnect */
353 		usb_set_intfdata(info->control, NULL);
354 		usb_driver_release_interface(driver, info->control);
355 		info->control = NULL;
356 	}
357 }
358 EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
359 
360 /*-------------------------------------------------------------------------
361  *
362  * Communications Device Class, Ethernet Control model
363  *
364  * Takes two interfaces.  The DATA interface is inactive till an altsetting
365  * is selected.  Configuration data includes class descriptors.  There's
366  * an optional status endpoint on the control interface.
367  *
368  * This should interop with whatever the 2.4 "CDCEther.c" driver
369  * (by Brad Hards) talked with, with more functionality.
370  *
371  *-------------------------------------------------------------------------*/
372 
373 static void dumpspeed(struct usbnet *dev, __le32 *speeds)
374 {
375 	netif_info(dev, timer, dev->net,
376 		   "link speeds: %u kbps up, %u kbps down\n",
377 		   __le32_to_cpu(speeds[0]) / 1000,
378 		   __le32_to_cpu(speeds[1]) / 1000);
379 }
380 
381 static void cdc_status(struct usbnet *dev, struct urb *urb)
382 {
383 	struct usb_cdc_notification	*event;
384 
385 	if (urb->actual_length < sizeof *event)
386 		return;
387 
388 	/* SPEED_CHANGE can get split into two 8-byte packets */
389 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
390 		dumpspeed(dev, (__le32 *) urb->transfer_buffer);
391 		return;
392 	}
393 
394 	event = urb->transfer_buffer;
395 	switch (event->bNotificationType) {
396 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
397 		netif_dbg(dev, timer, dev->net, "CDC: carrier %s\n",
398 			  event->wValue ? "on" : "off");
399 		if (event->wValue)
400 			netif_carrier_on(dev->net);
401 		else
402 			netif_carrier_off(dev->net);
403 		break;
404 	case USB_CDC_NOTIFY_SPEED_CHANGE:	/* tx/rx rates */
405 		netif_dbg(dev, timer, dev->net, "CDC: speed change (len %d)\n",
406 			  urb->actual_length);
407 		if (urb->actual_length != (sizeof *event + 8))
408 			set_bit(EVENT_STS_SPLIT, &dev->flags);
409 		else
410 			dumpspeed(dev, (__le32 *) &event[1]);
411 		break;
412 	/* USB_CDC_NOTIFY_RESPONSE_AVAILABLE can happen too (e.g. RNDIS),
413 	 * but there are no standard formats for the response data.
414 	 */
415 	default:
416 		netdev_err(dev->net, "CDC: unexpected notification %02x!\n",
417 			   event->bNotificationType);
418 		break;
419 	}
420 }
421 
422 static int cdc_bind(struct usbnet *dev, struct usb_interface *intf)
423 {
424 	int				status;
425 	struct cdc_state		*info = (void *) &dev->data;
426 
427 	status = usbnet_generic_cdc_bind(dev, intf);
428 	if (status < 0)
429 		return status;
430 
431 	status = usbnet_get_ethernet_addr(dev, info->ether->iMACAddress);
432 	if (status < 0) {
433 		usb_set_intfdata(info->data, NULL);
434 		usb_driver_release_interface(driver_of(intf), info->data);
435 		return status;
436 	}
437 
438 	/* FIXME cdc-ether has some multicast code too, though it complains
439 	 * in routine cases.  info->ether describes the multicast support.
440 	 * Implement that here, manipulating the cdc filter as needed.
441 	 */
442 	return 0;
443 }
444 
445 static int cdc_manage_power(struct usbnet *dev, int on)
446 {
447 	dev->intf->needs_remote_wakeup = on;
448 	return 0;
449 }
450 
451 static const struct driver_info	cdc_info = {
452 	.description =	"CDC Ethernet Device",
453 	.flags =	FLAG_ETHER,
454 	// .check_connect = cdc_check_connect,
455 	.bind =		cdc_bind,
456 	.unbind =	usbnet_cdc_unbind,
457 	.status =	cdc_status,
458 	.manage_power =	cdc_manage_power,
459 };
460 
461 static const struct driver_info mbm_info = {
462 	.description =	"Mobile Broadband Network Device",
463 	.flags =	FLAG_WWAN,
464 	.bind = 	cdc_bind,
465 	.unbind =	usbnet_cdc_unbind,
466 	.status =	cdc_status,
467 	.manage_power =	cdc_manage_power,
468 };
469 
470 /*-------------------------------------------------------------------------*/
471 
472 
473 static const struct usb_device_id	products [] = {
474 /*
475  * BLACKLIST !!
476  *
477  * First blacklist any products that are egregiously nonconformant
478  * with the CDC Ethernet specs.  Minor braindamage we cope with; when
479  * they're not even trying, needing a separate driver is only the first
480  * of the differences to show up.
481  */
482 
483 #define	ZAURUS_MASTER_INTERFACE \
484 	.bInterfaceClass	= USB_CLASS_COMM, \
485 	.bInterfaceSubClass	= USB_CDC_SUBCLASS_ETHERNET, \
486 	.bInterfaceProtocol	= USB_CDC_PROTO_NONE
487 
488 /* SA-1100 based Sharp Zaurus ("collie"), or compatible;
489  * wire-incompatible with true CDC Ethernet implementations.
490  * (And, it seems, needlessly so...)
491  */
492 {
493 	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
494 			  | USB_DEVICE_ID_MATCH_DEVICE,
495 	.idVendor		= 0x04DD,
496 	.idProduct		= 0x8004,
497 	ZAURUS_MASTER_INTERFACE,
498 	.driver_info		= 0,
499 },
500 
501 /* PXA-25x based Sharp Zaurii.  Note that it seems some of these
502  * (later models especially) may have shipped only with firmware
503  * advertising false "CDC MDLM" compatibility ... but we're not
504  * clear which models did that, so for now let's assume the worst.
505  */
506 {
507 	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
508 			  | USB_DEVICE_ID_MATCH_DEVICE,
509 	.idVendor		= 0x04DD,
510 	.idProduct		= 0x8005,	/* A-300 */
511 	ZAURUS_MASTER_INTERFACE,
512 	.driver_info		= 0,
513 }, {
514 	.match_flags	=   USB_DEVICE_ID_MATCH_INT_INFO
515 			  | USB_DEVICE_ID_MATCH_DEVICE,
516 	.idVendor		= 0x04DD,
517 	.idProduct		= 0x8006,	/* B-500/SL-5600 */
518 	ZAURUS_MASTER_INTERFACE,
519 	.driver_info		= 0,
520 }, {
521 	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
522 	          | USB_DEVICE_ID_MATCH_DEVICE,
523 	.idVendor		= 0x04DD,
524 	.idProduct		= 0x8007,	/* C-700 */
525 	ZAURUS_MASTER_INTERFACE,
526 	.driver_info		= 0,
527 }, {
528 	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
529 		 | USB_DEVICE_ID_MATCH_DEVICE,
530 	.idVendor               = 0x04DD,
531 	.idProduct              = 0x9031,	/* C-750 C-760 */
532 	ZAURUS_MASTER_INTERFACE,
533 	.driver_info		= 0,
534 }, {
535 	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
536 		 | USB_DEVICE_ID_MATCH_DEVICE,
537 	.idVendor               = 0x04DD,
538 	.idProduct              = 0x9032,	/* SL-6000 */
539 	ZAURUS_MASTER_INTERFACE,
540 	.driver_info		= 0,
541 }, {
542 	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
543 		 | USB_DEVICE_ID_MATCH_DEVICE,
544 	.idVendor               = 0x04DD,
545 	/* reported with some C860 units */
546 	.idProduct              = 0x9050,	/* C-860 */
547 	ZAURUS_MASTER_INTERFACE,
548 	.driver_info		= 0,
549 },
550 
551 /* Olympus has some models with a Zaurus-compatible option.
552  * R-1000 uses a FreeScale i.MXL cpu (ARMv4T)
553  */
554 {
555 	.match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
556 		 | USB_DEVICE_ID_MATCH_DEVICE,
557 	.idVendor               = 0x07B4,
558 	.idProduct              = 0x0F02,	/* R-1000 */
559 	ZAURUS_MASTER_INTERFACE,
560 	.driver_info		= 0,
561 },
562 
563 /*
564  * WHITELIST!!!
565  *
566  * CDC Ether uses two interfaces, not necessarily consecutive.
567  * We match the main interface, ignoring the optional device
568  * class so we could handle devices that aren't exclusively
569  * CDC ether.
570  *
571  * NOTE:  this match must come AFTER entries blacklisting devices
572  * because of bugs/quirks in a given product (like Zaurus, above).
573  */
574 {
575 	USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ETHERNET,
576 			USB_CDC_PROTO_NONE),
577 	.driver_info = (unsigned long) &cdc_info,
578 }, {
579 	USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MDLM,
580 			USB_CDC_PROTO_NONE),
581 	.driver_info = (unsigned long)&mbm_info,
582 
583 },
584 	{ },		// END
585 };
586 MODULE_DEVICE_TABLE(usb, products);
587 
588 static struct usb_driver cdc_driver = {
589 	.name =		"cdc_ether",
590 	.id_table =	products,
591 	.probe =	usbnet_probe,
592 	.disconnect =	usbnet_disconnect,
593 	.suspend =	usbnet_suspend,
594 	.resume =	usbnet_resume,
595 	.reset_resume =	usbnet_resume,
596 	.supports_autosuspend = 1,
597 };
598 
599 
600 static int __init cdc_init(void)
601 {
602 	BUILD_BUG_ON((sizeof(((struct usbnet *)0)->data)
603 			< sizeof(struct cdc_state)));
604 
605  	return usb_register(&cdc_driver);
606 }
607 module_init(cdc_init);
608 
609 static void __exit cdc_exit(void)
610 {
611  	usb_deregister(&cdc_driver);
612 }
613 module_exit(cdc_exit);
614 
615 MODULE_AUTHOR("David Brownell");
616 MODULE_DESCRIPTION("USB CDC Ethernet devices");
617 MODULE_LICENSE("GPL");
618