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 ECM_STATUS_INTERVAL_MS 32
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 = ECM_STATUS_INTERVAL_MS,
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 = USB_MS_TO_HS_INTERVAL(ECM_STATUS_INTERVAL_MS),
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 = USB_MS_TO_HS_INTERVAL(ECM_STATUS_INTERVAL_MS),
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_iad_descriptor,
334 (struct usb_descriptor_header *) &ecm_control_intf,
335 (struct usb_descriptor_header *) &ecm_header_desc,
336 (struct usb_descriptor_header *) &ecm_union_desc,
337 (struct usb_descriptor_header *) &ecm_desc,
338
339 /* NOTE: status endpoint might need to be removed */
340 (struct usb_descriptor_header *) &ss_ecm_notify_desc,
341 (struct usb_descriptor_header *) &ss_ecm_intr_comp_desc,
342
343 /* data interface, altsettings 0 and 1 */
344 (struct usb_descriptor_header *) &ecm_data_nop_intf,
345 (struct usb_descriptor_header *) &ecm_data_intf,
346 (struct usb_descriptor_header *) &ss_ecm_in_desc,
347 (struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
348 (struct usb_descriptor_header *) &ss_ecm_out_desc,
349 (struct usb_descriptor_header *) &ss_ecm_bulk_comp_desc,
350 NULL,
351 };
352
353 /* string descriptors: */
354
355 static struct usb_string ecm_string_defs[] = {
356 [0].s = "CDC Ethernet Control Model (ECM)",
357 [1].s = "",
358 [2].s = "CDC Ethernet Data",
359 [3].s = "CDC ECM",
360 { } /* end of list */
361 };
362
363 static struct usb_gadget_strings ecm_string_table = {
364 .language = 0x0409, /* en-us */
365 .strings = ecm_string_defs,
366 };
367
368 static struct usb_gadget_strings *ecm_strings[] = {
369 &ecm_string_table,
370 NULL,
371 };
372
373 /*-------------------------------------------------------------------------*/
374
ecm_do_notify(struct f_ecm * ecm)375 static void ecm_do_notify(struct f_ecm *ecm)
376 {
377 struct usb_request *req = ecm->notify_req;
378 struct usb_cdc_notification *event;
379 struct usb_composite_dev *cdev = ecm->port.func.config->cdev;
380 __le32 *data;
381 int status;
382
383 /* notification already in flight? */
384 if (!req)
385 return;
386
387 event = req->buf;
388 switch (ecm->notify_state) {
389 case ECM_NOTIFY_NONE:
390 return;
391
392 case ECM_NOTIFY_CONNECT:
393 event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
394 if (ecm->is_open)
395 event->wValue = cpu_to_le16(1);
396 else
397 event->wValue = cpu_to_le16(0);
398 event->wLength = 0;
399 req->length = sizeof *event;
400
401 DBG(cdev, "notify connect %s\n",
402 ecm->is_open ? "true" : "false");
403 ecm->notify_state = ECM_NOTIFY_SPEED;
404 break;
405
406 case ECM_NOTIFY_SPEED:
407 event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
408 event->wValue = cpu_to_le16(0);
409 event->wLength = cpu_to_le16(8);
410 req->length = ECM_STATUS_BYTECOUNT;
411
412 /* SPEED_CHANGE data is up/down speeds in bits/sec */
413 data = req->buf + sizeof *event;
414 data[0] = cpu_to_le32(ecm_bitrate(cdev->gadget));
415 data[1] = data[0];
416
417 DBG(cdev, "notify speed %d\n", ecm_bitrate(cdev->gadget));
418 ecm->notify_state = ECM_NOTIFY_NONE;
419 break;
420 }
421 event->bmRequestType = 0xA1;
422 event->wIndex = cpu_to_le16(ecm->ctrl_id);
423
424 ecm->notify_req = NULL;
425 status = usb_ep_queue(ecm->notify, req, GFP_ATOMIC);
426 if (status < 0) {
427 ecm->notify_req = req;
428 DBG(cdev, "notify --> %d\n", status);
429 }
430 }
431
ecm_notify(struct f_ecm * ecm)432 static void ecm_notify(struct f_ecm *ecm)
433 {
434 /* NOTE on most versions of Linux, host side cdc-ethernet
435 * won't listen for notifications until its netdevice opens.
436 * The first notification then sits in the FIFO for a long
437 * time, and the second one is queued.
438 */
439 ecm->notify_state = ECM_NOTIFY_CONNECT;
440 ecm_do_notify(ecm);
441 }
442
ecm_notify_complete(struct usb_ep * ep,struct usb_request * req)443 static void ecm_notify_complete(struct usb_ep *ep, struct usb_request *req)
444 {
445 struct f_ecm *ecm = req->context;
446 struct usb_composite_dev *cdev = ecm->port.func.config->cdev;
447 struct usb_cdc_notification *event = req->buf;
448
449 switch (req->status) {
450 case 0:
451 /* no fault */
452 break;
453 case -ECONNRESET:
454 case -ESHUTDOWN:
455 ecm->notify_state = ECM_NOTIFY_NONE;
456 break;
457 default:
458 DBG(cdev, "event %02x --> %d\n",
459 event->bNotificationType, req->status);
460 break;
461 }
462 ecm->notify_req = req;
463 ecm_do_notify(ecm);
464 }
465
ecm_setup(struct usb_function * f,const struct usb_ctrlrequest * ctrl)466 static int ecm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
467 {
468 struct f_ecm *ecm = func_to_ecm(f);
469 struct usb_composite_dev *cdev = f->config->cdev;
470 struct usb_request *req = cdev->req;
471 int value = -EOPNOTSUPP;
472 u16 w_index = le16_to_cpu(ctrl->wIndex);
473 u16 w_value = le16_to_cpu(ctrl->wValue);
474 u16 w_length = le16_to_cpu(ctrl->wLength);
475
476 /* composite driver infrastructure handles everything except
477 * CDC class messages; interface activation uses set_alt().
478 */
479 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
480 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
481 | USB_CDC_SET_ETHERNET_PACKET_FILTER:
482 /* see 6.2.30: no data, wIndex = interface,
483 * wValue = packet filter bitmap
484 */
485 if (w_length != 0 || w_index != ecm->ctrl_id)
486 goto invalid;
487 DBG(cdev, "packet filter %02x\n", w_value);
488 /* REVISIT locking of cdc_filter. This assumes the UDC
489 * driver won't have a concurrent packet TX irq running on
490 * another CPU; or that if it does, this write is atomic...
491 */
492 ecm->port.cdc_filter = w_value;
493 value = 0;
494 break;
495
496 /* and optionally:
497 * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
498 * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
499 * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
500 * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
501 * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
502 * case USB_CDC_GET_ETHERNET_STATISTIC:
503 */
504
505 default:
506 invalid:
507 DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
508 ctrl->bRequestType, ctrl->bRequest,
509 w_value, w_index, w_length);
510 }
511
512 /* respond with data transfer or status phase? */
513 if (value >= 0) {
514 DBG(cdev, "ecm req%02x.%02x v%04x i%04x l%d\n",
515 ctrl->bRequestType, ctrl->bRequest,
516 w_value, w_index, w_length);
517 req->zero = 0;
518 req->length = value;
519 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
520 if (value < 0)
521 ERROR(cdev, "ecm req %02x.%02x response err %d\n",
522 ctrl->bRequestType, ctrl->bRequest,
523 value);
524 }
525
526 /* device either stalls (value < 0) or reports success */
527 return value;
528 }
529
530
ecm_set_alt(struct usb_function * f,unsigned intf,unsigned alt)531 static int ecm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
532 {
533 struct f_ecm *ecm = func_to_ecm(f);
534 struct usb_composite_dev *cdev = f->config->cdev;
535
536 /* Control interface has only altsetting 0 */
537 if (intf == ecm->ctrl_id) {
538 if (alt != 0)
539 goto fail;
540
541 if (ecm->notify->driver_data) {
542 VDBG(cdev, "reset ecm control %d\n", intf);
543 usb_ep_disable(ecm->notify);
544 }
545 if (!(ecm->notify->desc)) {
546 VDBG(cdev, "init ecm ctrl %d\n", intf);
547 if (config_ep_by_speed(cdev->gadget, f, ecm->notify))
548 goto fail;
549 }
550 usb_ep_enable(ecm->notify);
551 ecm->notify->driver_data = ecm;
552
553 /* Data interface has two altsettings, 0 and 1 */
554 } else if (intf == ecm->data_id) {
555 if (alt > 1)
556 goto fail;
557
558 if (ecm->port.in_ep->driver_data) {
559 DBG(cdev, "reset ecm\n");
560 gether_disconnect(&ecm->port);
561 }
562
563 if (!ecm->port.in_ep->desc ||
564 !ecm->port.out_ep->desc) {
565 DBG(cdev, "init ecm\n");
566 if (config_ep_by_speed(cdev->gadget, f,
567 ecm->port.in_ep) ||
568 config_ep_by_speed(cdev->gadget, f,
569 ecm->port.out_ep)) {
570 ecm->port.in_ep->desc = NULL;
571 ecm->port.out_ep->desc = NULL;
572 goto fail;
573 }
574 }
575
576 /* CDC Ethernet only sends data in non-default altsettings.
577 * Changing altsettings resets filters, statistics, etc.
578 */
579 if (alt == 1) {
580 struct net_device *net;
581
582 /* Enable zlps by default for ECM conformance;
583 * override for musb_hdrc (avoids txdma ovhead).
584 */
585 ecm->port.is_zlp_ok = !(gadget_is_musbhdrc(cdev->gadget)
586 );
587 ecm->port.cdc_filter = DEFAULT_FILTER;
588 DBG(cdev, "activate ecm\n");
589 net = gether_connect(&ecm->port);
590 if (IS_ERR(net))
591 return PTR_ERR(net);
592 }
593
594 /* NOTE this can be a minor disagreement with the ECM spec,
595 * which says speed notifications will "always" follow
596 * connection notifications. But we allow one connect to
597 * follow another (if the first is in flight), and instead
598 * just guarantee that a speed notification is always sent.
599 */
600 ecm_notify(ecm);
601 } else
602 goto fail;
603
604 return 0;
605 fail:
606 return -EINVAL;
607 }
608
609 /* Because the data interface supports multiple altsettings,
610 * this ECM function *MUST* implement a get_alt() method.
611 */
ecm_get_alt(struct usb_function * f,unsigned intf)612 static int ecm_get_alt(struct usb_function *f, unsigned intf)
613 {
614 struct f_ecm *ecm = func_to_ecm(f);
615
616 if (intf == ecm->ctrl_id)
617 return 0;
618 return ecm->port.in_ep->driver_data ? 1 : 0;
619 }
620
ecm_disable(struct usb_function * f)621 static void ecm_disable(struct usb_function *f)
622 {
623 struct f_ecm *ecm = func_to_ecm(f);
624 struct usb_composite_dev *cdev = f->config->cdev;
625
626 DBG(cdev, "ecm deactivated\n");
627
628 if (ecm->port.in_ep->driver_data)
629 gether_disconnect(&ecm->port);
630
631 if (ecm->notify->driver_data) {
632 usb_ep_disable(ecm->notify);
633 ecm->notify->driver_data = NULL;
634 ecm->notify->desc = NULL;
635 }
636 }
637
638 /*-------------------------------------------------------------------------*/
639
640 /*
641 * Callbacks let us notify the host about connect/disconnect when the
642 * net device is opened or closed.
643 *
644 * For testing, note that link states on this side include both opened
645 * and closed variants of:
646 *
647 * - disconnected/unconfigured
648 * - configured but inactive (data alt 0)
649 * - configured and active (data alt 1)
650 *
651 * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
652 * SET_INTERFACE (altsetting). Remember also that "configured" doesn't
653 * imply the host is actually polling the notification endpoint, and
654 * likewise that "active" doesn't imply it's actually using the data
655 * endpoints for traffic.
656 */
657
ecm_open(struct gether * geth)658 static void ecm_open(struct gether *geth)
659 {
660 struct f_ecm *ecm = func_to_ecm(&geth->func);
661
662 DBG(ecm->port.func.config->cdev, "%s\n", __func__);
663
664 ecm->is_open = true;
665 ecm_notify(ecm);
666 }
667
ecm_close(struct gether * geth)668 static void ecm_close(struct gether *geth)
669 {
670 struct f_ecm *ecm = func_to_ecm(&geth->func);
671
672 DBG(ecm->port.func.config->cdev, "%s\n", __func__);
673
674 ecm->is_open = false;
675 ecm_notify(ecm);
676 }
677
678 /*-------------------------------------------------------------------------*/
679
680 /* ethernet function driver setup/binding */
681
682 static int
ecm_bind(struct usb_configuration * c,struct usb_function * f)683 ecm_bind(struct usb_configuration *c, struct usb_function *f)
684 {
685 struct usb_composite_dev *cdev = c->cdev;
686 struct f_ecm *ecm = func_to_ecm(f);
687 int status;
688 struct usb_ep *ep;
689
690 /* allocate instance-specific interface IDs */
691 status = usb_interface_id(c, f);
692 if (status < 0)
693 goto fail;
694 ecm->ctrl_id = status;
695 ecm_iad_descriptor.bFirstInterface = status;
696
697 ecm_control_intf.bInterfaceNumber = status;
698 ecm_union_desc.bMasterInterface0 = status;
699
700 status = usb_interface_id(c, f);
701 if (status < 0)
702 goto fail;
703 ecm->data_id = status;
704
705 ecm_data_nop_intf.bInterfaceNumber = status;
706 ecm_data_intf.bInterfaceNumber = status;
707 ecm_union_desc.bSlaveInterface0 = status;
708
709 status = -ENODEV;
710
711 /* allocate instance-specific endpoints */
712 ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_in_desc);
713 if (!ep)
714 goto fail;
715 ecm->port.in_ep = ep;
716 ep->driver_data = cdev; /* claim */
717
718 ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_out_desc);
719 if (!ep)
720 goto fail;
721 ecm->port.out_ep = ep;
722 ep->driver_data = cdev; /* claim */
723
724 /* NOTE: a status/notification endpoint is *OPTIONAL* but we
725 * don't treat it that way. It's simpler, and some newer CDC
726 * profiles (wireless handsets) no longer treat it as optional.
727 */
728 ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_notify_desc);
729 if (!ep)
730 goto fail;
731 ecm->notify = ep;
732 ep->driver_data = cdev; /* claim */
733
734 status = -ENOMEM;
735
736 /* allocate notification request and buffer */
737 ecm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
738 if (!ecm->notify_req)
739 goto fail;
740 ecm->notify_req->buf = kmalloc(ECM_STATUS_BYTECOUNT, GFP_KERNEL);
741 if (!ecm->notify_req->buf)
742 goto fail;
743 ecm->notify_req->context = ecm;
744 ecm->notify_req->complete = ecm_notify_complete;
745
746 /* support all relevant hardware speeds... we expect that when
747 * hardware is dual speed, all bulk-capable endpoints work at
748 * both speeds
749 */
750 hs_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
751 hs_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
752 hs_ecm_notify_desc.bEndpointAddress =
753 fs_ecm_notify_desc.bEndpointAddress;
754
755 ss_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
756 ss_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
757 ss_ecm_notify_desc.bEndpointAddress =
758 fs_ecm_notify_desc.bEndpointAddress;
759
760 status = usb_assign_descriptors(f, ecm_fs_function, ecm_hs_function,
761 ecm_ss_function);
762 if (status)
763 goto fail;
764
765 /* NOTE: all that is done without knowing or caring about
766 * the network link ... which is unavailable to this code
767 * until we're activated via set_alt().
768 */
769
770 ecm->port.open = ecm_open;
771 ecm->port.close = ecm_close;
772
773 DBG(cdev, "CDC Ethernet: %s speed IN/%s OUT/%s NOTIFY/%s\n",
774 gadget_is_superspeed(c->cdev->gadget) ? "super" :
775 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
776 ecm->port.in_ep->name, ecm->port.out_ep->name,
777 ecm->notify->name);
778 return 0;
779
780 fail:
781 if (ecm->notify_req) {
782 kfree(ecm->notify_req->buf);
783 usb_ep_free_request(ecm->notify, ecm->notify_req);
784 }
785
786 /* we might as well release our claims on endpoints */
787 if (ecm->notify)
788 ecm->notify->driver_data = NULL;
789 if (ecm->port.out_ep)
790 ecm->port.out_ep->driver_data = NULL;
791 if (ecm->port.in_ep)
792 ecm->port.in_ep->driver_data = NULL;
793
794 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
795
796 return status;
797 }
798
799 static void
ecm_unbind(struct usb_configuration * c,struct usb_function * f)800 ecm_unbind(struct usb_configuration *c, struct usb_function *f)
801 {
802 struct f_ecm *ecm = func_to_ecm(f);
803
804 DBG(c->cdev, "ecm unbind\n");
805
806 ecm_string_defs[0].id = 0;
807 usb_free_all_descriptors(f);
808
809 kfree(ecm->notify_req->buf);
810 usb_ep_free_request(ecm->notify, ecm->notify_req);
811 kfree(ecm);
812 }
813
814 /**
815 * ecm_bind_config - add CDC Ethernet network link to a configuration
816 * @c: the configuration to support the network link
817 * @ethaddr: a buffer in which the ethernet address of the host side
818 * side of the link was recorded
819 * @dev: eth_dev structure
820 * Context: single threaded during gadget setup
821 *
822 * Returns zero on success, else negative errno.
823 *
824 * Caller must have called @gether_setup(). Caller is also responsible
825 * for calling @gether_cleanup() before module unload.
826 */
827 int
ecm_bind_config(struct usb_configuration * c,u8 ethaddr[ETH_ALEN],struct eth_dev * dev)828 ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
829 struct eth_dev *dev)
830 {
831 struct f_ecm *ecm;
832 int status;
833
834 if (!can_support_ecm(c->cdev->gadget) || !ethaddr)
835 return -EINVAL;
836
837 if (ecm_string_defs[0].id == 0) {
838 status = usb_string_ids_tab(c->cdev, ecm_string_defs);
839 if (status)
840 return status;
841
842 ecm_control_intf.iInterface = ecm_string_defs[0].id;
843 ecm_data_intf.iInterface = ecm_string_defs[2].id;
844 ecm_desc.iMACAddress = ecm_string_defs[1].id;
845 ecm_iad_descriptor.iFunction = ecm_string_defs[3].id;
846 }
847
848 /* allocate and initialize one new instance */
849 ecm = kzalloc(sizeof *ecm, GFP_KERNEL);
850 if (!ecm)
851 return -ENOMEM;
852
853 /* export host's Ethernet address in CDC format */
854 snprintf(ecm->ethaddr, sizeof ecm->ethaddr, "%pm", ethaddr);
855 ecm_string_defs[1].s = ecm->ethaddr;
856
857 ecm->port.ioport = dev;
858 ecm->port.cdc_filter = DEFAULT_FILTER;
859
860 ecm->port.func.name = "cdc_ethernet";
861 ecm->port.func.strings = ecm_strings;
862 /* descriptors are per-instance copies */
863 ecm->port.func.bind = ecm_bind;
864 ecm->port.func.unbind = ecm_unbind;
865 ecm->port.func.set_alt = ecm_set_alt;
866 ecm->port.func.get_alt = ecm_get_alt;
867 ecm->port.func.setup = ecm_setup;
868 ecm->port.func.disable = ecm_disable;
869
870 status = usb_add_function(c, &ecm->port.func);
871 if (status)
872 kfree(ecm);
873 return status;
874 }
875