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