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1/*
2 * f_rndis.c -- RNDIS link function driver
3 *
4 * Copyright (C) 2003-2005,2008 David Brownell
5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
6 * Copyright (C) 2008 Nokia Corporation
7 * Copyright (C) 2009 Samsung Electronics
8 * Author: Michal Nazarewicz (mina86@mina86.com)
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 */
15
16/* #define VERBOSE_DEBUG */
17
18#include <linux/slab.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/device.h>
22#include <linux/etherdevice.h>
23
24#include <linux/atomic.h>
25
26#include "u_ether.h"
27#include "u_ether_configfs.h"
28#include "u_rndis.h"
29#include "rndis.h"
30#include "configfs.h"
31
32/*
33 * This function is an RNDIS Ethernet port -- a Microsoft protocol that's
34 * been promoted instead of the standard CDC Ethernet. The published RNDIS
35 * spec is ambiguous, incomplete, and needlessly complex. Variants such as
36 * ActiveSync have even worse status in terms of specification.
37 *
38 * In short: it's a protocol controlled by (and for) Microsoft, not for an
39 * Open ecosystem or markets. Linux supports it *only* because Microsoft
40 * doesn't support the CDC Ethernet standard.
41 *
42 * The RNDIS data transfer model is complex, with multiple Ethernet packets
43 * per USB message, and out of band data. The control model is built around
44 * what's essentially an "RNDIS RPC" protocol. It's all wrapped in a CDC ACM
45 * (modem, not Ethernet) veneer, with those ACM descriptors being entirely
46 * useless (they're ignored). RNDIS expects to be the only function in its
47 * configuration, so it's no real help if you need composite devices; and
48 * it expects to be the first configuration too.
49 *
50 * There is a single technical advantage of RNDIS over CDC Ethernet, if you
51 * discount the fluff that its RPC can be made to deliver: it doesn't need
52 * a NOP altsetting for the data interface. That lets it work on some of the
53 * "so smart it's stupid" hardware which takes over configuration changes
54 * from the software, and adds restrictions like "no altsettings".
55 *
56 * Unfortunately MSFT's RNDIS drivers are buggy. They hang or oops, and
57 * have all sorts of contrary-to-specification oddities that can prevent
58 * them from working sanely. Since bugfixes (or accurate specs, letting
59 * Linux work around those bugs) are unlikely to ever come from MSFT, you
60 * may want to avoid using RNDIS on purely operational grounds.
61 *
62 * Omissions from the RNDIS 1.0 specification include:
63 *
64 * - Power management ... references data that's scattered around lots
65 * of other documentation, which is incorrect/incomplete there too.
66 *
67 * - There are various undocumented protocol requirements, like the need
68 * to send garbage in some control-OUT messages.
69 *
70 * - MS-Windows drivers sometimes emit undocumented requests.
71 */
72
73struct f_rndis {
74 struct gether port;
75 u8 ctrl_id, data_id;
76 u8 ethaddr[ETH_ALEN];
77 u32 vendorID;
78 const char *manufacturer;
79 struct rndis_params *params;
80
81 struct usb_ep *notify;
82 struct usb_request *notify_req;
83 atomic_t notify_count;
84};
85
86static inline struct f_rndis *func_to_rndis(struct usb_function *f)
87{
88 return container_of(f, struct f_rndis, port.func);
89}
90
91/* peak (theoretical) bulk transfer rate in bits-per-second */
92static unsigned int bitrate(struct usb_gadget *g)
93{
94 if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
95 return 13 * 1024 * 8 * 1000 * 8;
96 else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
97 return 13 * 512 * 8 * 1000 * 8;
98 else
99 return 19 * 64 * 1 * 1000 * 8;
100}
101
102/*-------------------------------------------------------------------------*/
103
104/*
105 */
106
107#define RNDIS_STATUS_INTERVAL_MS 32
108#define STATUS_BYTECOUNT 8 /* 8 bytes data */
109
110
111/* interface descriptor: */
112
113static struct usb_interface_descriptor rndis_control_intf = {
114 .bLength = sizeof rndis_control_intf,
115 .bDescriptorType = USB_DT_INTERFACE,
116
117 /* .bInterfaceNumber = DYNAMIC */
118 /* status endpoint is optional; this could be patched later */
119 .bNumEndpoints = 1,
120 .bInterfaceClass = USB_CLASS_COMM,
121 .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
122 .bInterfaceProtocol = USB_CDC_ACM_PROTO_VENDOR,
123 /* .iInterface = DYNAMIC */
124};
125
126static struct usb_cdc_header_desc header_desc = {
127 .bLength = sizeof header_desc,
128 .bDescriptorType = USB_DT_CS_INTERFACE,
129 .bDescriptorSubType = USB_CDC_HEADER_TYPE,
130
131 .bcdCDC = cpu_to_le16(0x0110),
132};
133
134static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = {
135 .bLength = sizeof call_mgmt_descriptor,
136 .bDescriptorType = USB_DT_CS_INTERFACE,
137 .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE,
138
139 .bmCapabilities = 0x00,
140 .bDataInterface = 0x01,
141};
142
143static struct usb_cdc_acm_descriptor rndis_acm_descriptor = {
144 .bLength = sizeof rndis_acm_descriptor,
145 .bDescriptorType = USB_DT_CS_INTERFACE,
146 .bDescriptorSubType = USB_CDC_ACM_TYPE,
147
148 .bmCapabilities = 0x00,
149};
150
151static struct usb_cdc_union_desc rndis_union_desc = {
152 .bLength = sizeof(rndis_union_desc),
153 .bDescriptorType = USB_DT_CS_INTERFACE,
154 .bDescriptorSubType = USB_CDC_UNION_TYPE,
155 /* .bMasterInterface0 = DYNAMIC */
156 /* .bSlaveInterface0 = DYNAMIC */
157};
158
159/* the data interface has two bulk endpoints */
160
161static struct usb_interface_descriptor rndis_data_intf = {
162 .bLength = sizeof rndis_data_intf,
163 .bDescriptorType = USB_DT_INTERFACE,
164
165 /* .bInterfaceNumber = DYNAMIC */
166 .bNumEndpoints = 2,
167 .bInterfaceClass = USB_CLASS_CDC_DATA,
168 .bInterfaceSubClass = 0,
169 .bInterfaceProtocol = 0,
170 /* .iInterface = DYNAMIC */
171};
172
173
174static struct usb_interface_assoc_descriptor
175rndis_iad_descriptor = {
176 .bLength = sizeof rndis_iad_descriptor,
177 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
178
179 .bFirstInterface = 0, /* XXX, hardcoded */
180 .bInterfaceCount = 2, // control + data
181 .bFunctionClass = USB_CLASS_COMM,
182 .bFunctionSubClass = USB_CDC_SUBCLASS_ETHERNET,
183 .bFunctionProtocol = USB_CDC_PROTO_NONE,
184 /* .iFunction = DYNAMIC */
185};
186
187/* full speed support: */
188
189static struct usb_endpoint_descriptor fs_notify_desc = {
190 .bLength = USB_DT_ENDPOINT_SIZE,
191 .bDescriptorType = USB_DT_ENDPOINT,
192
193 .bEndpointAddress = USB_DIR_IN,
194 .bmAttributes = USB_ENDPOINT_XFER_INT,
195 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT),
196 .bInterval = RNDIS_STATUS_INTERVAL_MS,
197};
198
199static struct usb_endpoint_descriptor fs_in_desc = {
200 .bLength = USB_DT_ENDPOINT_SIZE,
201 .bDescriptorType = USB_DT_ENDPOINT,
202
203 .bEndpointAddress = USB_DIR_IN,
204 .bmAttributes = USB_ENDPOINT_XFER_BULK,
205};
206
207static struct usb_endpoint_descriptor fs_out_desc = {
208 .bLength = USB_DT_ENDPOINT_SIZE,
209 .bDescriptorType = USB_DT_ENDPOINT,
210
211 .bEndpointAddress = USB_DIR_OUT,
212 .bmAttributes = USB_ENDPOINT_XFER_BULK,
213};
214
215static struct usb_descriptor_header *eth_fs_function[] = {
216 (struct usb_descriptor_header *) &rndis_iad_descriptor,
217
218 /* control interface matches ACM, not Ethernet */
219 (struct usb_descriptor_header *) &rndis_control_intf,
220 (struct usb_descriptor_header *) &header_desc,
221 (struct usb_descriptor_header *) &call_mgmt_descriptor,
222 (struct usb_descriptor_header *) &rndis_acm_descriptor,
223 (struct usb_descriptor_header *) &rndis_union_desc,
224 (struct usb_descriptor_header *) &fs_notify_desc,
225
226 /* data interface has no altsetting */
227 (struct usb_descriptor_header *) &rndis_data_intf,
228 (struct usb_descriptor_header *) &fs_in_desc,
229 (struct usb_descriptor_header *) &fs_out_desc,
230 NULL,
231};
232
233/* high speed support: */
234
235static struct usb_endpoint_descriptor hs_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(STATUS_BYTECOUNT),
242 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
243};
244
245static struct usb_endpoint_descriptor hs_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
254static struct usb_endpoint_descriptor hs_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
263static struct usb_descriptor_header *eth_hs_function[] = {
264 (struct usb_descriptor_header *) &rndis_iad_descriptor,
265
266 /* control interface matches ACM, not Ethernet */
267 (struct usb_descriptor_header *) &rndis_control_intf,
268 (struct usb_descriptor_header *) &header_desc,
269 (struct usb_descriptor_header *) &call_mgmt_descriptor,
270 (struct usb_descriptor_header *) &rndis_acm_descriptor,
271 (struct usb_descriptor_header *) &rndis_union_desc,
272 (struct usb_descriptor_header *) &hs_notify_desc,
273
274 /* data interface has no altsetting */
275 (struct usb_descriptor_header *) &rndis_data_intf,
276 (struct usb_descriptor_header *) &hs_in_desc,
277 (struct usb_descriptor_header *) &hs_out_desc,
278 NULL,
279};
280
281/* super speed support: */
282
283static struct usb_endpoint_descriptor ss_notify_desc = {
284 .bLength = USB_DT_ENDPOINT_SIZE,
285 .bDescriptorType = USB_DT_ENDPOINT,
286
287 .bEndpointAddress = USB_DIR_IN,
288 .bmAttributes = USB_ENDPOINT_XFER_INT,
289 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT),
290 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
291};
292
293static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = {
294 .bLength = sizeof ss_intr_comp_desc,
295 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
296
297 /* the following 3 values can be tweaked if necessary */
298 /* .bMaxBurst = 0, */
299 /* .bmAttributes = 0, */
300 .wBytesPerInterval = cpu_to_le16(STATUS_BYTECOUNT),
301};
302
303static struct usb_endpoint_descriptor ss_in_desc = {
304 .bLength = USB_DT_ENDPOINT_SIZE,
305 .bDescriptorType = USB_DT_ENDPOINT,
306
307 .bEndpointAddress = USB_DIR_IN,
308 .bmAttributes = USB_ENDPOINT_XFER_BULK,
309 .wMaxPacketSize = cpu_to_le16(1024),
310};
311
312static struct usb_endpoint_descriptor ss_out_desc = {
313 .bLength = USB_DT_ENDPOINT_SIZE,
314 .bDescriptorType = USB_DT_ENDPOINT,
315
316 .bEndpointAddress = USB_DIR_OUT,
317 .bmAttributes = USB_ENDPOINT_XFER_BULK,
318 .wMaxPacketSize = cpu_to_le16(1024),
319};
320
321static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = {
322 .bLength = sizeof ss_bulk_comp_desc,
323 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
324
325 /* the following 2 values can be tweaked if necessary */
326 /* .bMaxBurst = 0, */
327 /* .bmAttributes = 0, */
328};
329
330static struct usb_descriptor_header *eth_ss_function[] = {
331 (struct usb_descriptor_header *) &rndis_iad_descriptor,
332
333 /* control interface matches ACM, not Ethernet */
334 (struct usb_descriptor_header *) &rndis_control_intf,
335 (struct usb_descriptor_header *) &header_desc,
336 (struct usb_descriptor_header *) &call_mgmt_descriptor,
337 (struct usb_descriptor_header *) &rndis_acm_descriptor,
338 (struct usb_descriptor_header *) &rndis_union_desc,
339 (struct usb_descriptor_header *) &ss_notify_desc,
340 (struct usb_descriptor_header *) &ss_intr_comp_desc,
341
342 /* data interface has no altsetting */
343 (struct usb_descriptor_header *) &rndis_data_intf,
344 (struct usb_descriptor_header *) &ss_in_desc,
345 (struct usb_descriptor_header *) &ss_bulk_comp_desc,
346 (struct usb_descriptor_header *) &ss_out_desc,
347 (struct usb_descriptor_header *) &ss_bulk_comp_desc,
348 NULL,
349};
350
351/* string descriptors: */
352
353static struct usb_string rndis_string_defs[] = {
354 [0].s = "RNDIS Communications Control",
355 [1].s = "RNDIS Ethernet Data",
356 [2].s = "RNDIS",
357 { } /* end of list */
358};
359
360static struct usb_gadget_strings rndis_string_table = {
361 .language = 0x0409, /* en-us */
362 .strings = rndis_string_defs,
363};
364
365static struct usb_gadget_strings *rndis_strings[] = {
366 &rndis_string_table,
367 NULL,
368};
369
370/*-------------------------------------------------------------------------*/
371
372static struct sk_buff *rndis_add_header(struct gether *port,
373 struct sk_buff *skb)
374{
375 struct sk_buff *skb2;
376
377 if (!skb)
378 return NULL;
379
380 skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
381 rndis_add_hdr(skb2);
382
383 dev_kfree_skb(skb);
384 return skb2;
385}
386
387static void rndis_response_available(void *_rndis)
388{
389 struct f_rndis *rndis = _rndis;
390 struct usb_request *req = rndis->notify_req;
391 struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
392 __le32 *data = req->buf;
393 int status;
394
395 if (atomic_inc_return(&rndis->notify_count) != 1)
396 return;
397
398 /* Send RNDIS RESPONSE_AVAILABLE notification; a
399 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too
400 *
401 * This is the only notification defined by RNDIS.
402 */
403 data[0] = cpu_to_le32(1);
404 data[1] = cpu_to_le32(0);
405
406 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
407 if (status) {
408 atomic_dec(&rndis->notify_count);
409 DBG(cdev, "notify/0 --> %d\n", status);
410 }
411}
412
413static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
414{
415 struct f_rndis *rndis = req->context;
416 struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
417 int status = req->status;
418
419 /* after TX:
420 * - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control)
421 * - RNDIS_RESPONSE_AVAILABLE (status/irq)
422 */
423 switch (status) {
424 case -ECONNRESET:
425 case -ESHUTDOWN:
426 /* connection gone */
427 atomic_set(&rndis->notify_count, 0);
428 break;
429 default:
430 DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
431 ep->name, status,
432 req->actual, req->length);
433 /* FALLTHROUGH */
434 case 0:
435 if (ep != rndis->notify)
436 break;
437
438 /* handle multiple pending RNDIS_RESPONSE_AVAILABLE
439 * notifications by resending until we're done
440 */
441 if (atomic_dec_and_test(&rndis->notify_count))
442 break;
443 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
444 if (status) {
445 atomic_dec(&rndis->notify_count);
446 DBG(cdev, "notify/1 --> %d\n", status);
447 }
448 break;
449 }
450}
451
452static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req)
453{
454 struct f_rndis *rndis = req->context;
455 int status;
456
457 /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */
458// spin_lock(&dev->lock);
459 status = rndis_msg_parser(rndis->params, (u8 *) req->buf);
460 if (status < 0)
461 pr_err("RNDIS command error %d, %d/%d\n",
462 status, req->actual, req->length);
463// spin_unlock(&dev->lock);
464}
465
466static int
467rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
468{
469 struct f_rndis *rndis = func_to_rndis(f);
470 struct usb_composite_dev *cdev = f->config->cdev;
471 struct usb_request *req = cdev->req;
472 int value = -EOPNOTSUPP;
473 u16 w_index = le16_to_cpu(ctrl->wIndex);
474 u16 w_value = le16_to_cpu(ctrl->wValue);
475 u16 w_length = le16_to_cpu(ctrl->wLength);
476
477 /* composite driver infrastructure handles everything except
478 * CDC class messages; interface activation uses set_alt().
479 */
480 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
481
482 /* RNDIS uses the CDC command encapsulation mechanism to implement
483 * an RPC scheme, with much getting/setting of attributes by OID.
484 */
485 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
486 | USB_CDC_SEND_ENCAPSULATED_COMMAND:
487 if (w_value || w_index != rndis->ctrl_id)
488 goto invalid;
489 /* read the request; process it later */
490 value = w_length;
491 req->complete = rndis_command_complete;
492 req->context = rndis;
493 /* later, rndis_response_available() sends a notification */
494 break;
495
496 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
497 | USB_CDC_GET_ENCAPSULATED_RESPONSE:
498 if (w_value || w_index != rndis->ctrl_id)
499 goto invalid;
500 else {
501 u8 *buf;
502 u32 n;
503
504 /* return the result */
505 buf = rndis_get_next_response(rndis->params, &n);
506 if (buf) {
507 memcpy(req->buf, buf, n);
508 req->complete = rndis_response_complete;
509 req->context = rndis;
510 rndis_free_response(rndis->params, buf);
511 value = n;
512 }
513 /* else stalls ... spec says to avoid that */
514 }
515 break;
516
517 default:
518invalid:
519 VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
520 ctrl->bRequestType, ctrl->bRequest,
521 w_value, w_index, w_length);
522 }
523
524 /* respond with data transfer or status phase? */
525 if (value >= 0) {
526 DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n",
527 ctrl->bRequestType, ctrl->bRequest,
528 w_value, w_index, w_length);
529 req->zero = (value < w_length);
530 req->length = value;
531 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
532 if (value < 0)
533 ERROR(cdev, "rndis response on err %d\n", value);
534 }
535
536 /* device either stalls (value < 0) or reports success */
537 return value;
538}
539
540
541static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
542{
543 struct f_rndis *rndis = func_to_rndis(f);
544 struct usb_composite_dev *cdev = f->config->cdev;
545
546 /* we know alt == 0 */
547
548 if (intf == rndis->ctrl_id) {
549 VDBG(cdev, "reset rndis control %d\n", intf);
550 usb_ep_disable(rndis->notify);
551
552 if (!rndis->notify->desc) {
553 VDBG(cdev, "init rndis ctrl %d\n", intf);
554 if (config_ep_by_speed(cdev->gadget, f, rndis->notify))
555 goto fail;
556 }
557 usb_ep_enable(rndis->notify);
558
559 } else if (intf == rndis->data_id) {
560 struct net_device *net;
561
562 if (rndis->port.in_ep->enabled) {
563 DBG(cdev, "reset rndis\n");
564 gether_disconnect(&rndis->port);
565 }
566
567 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) {
568 DBG(cdev, "init rndis\n");
569 if (config_ep_by_speed(cdev->gadget, f,
570 rndis->port.in_ep) ||
571 config_ep_by_speed(cdev->gadget, f,
572 rndis->port.out_ep)) {
573 rndis->port.in_ep->desc = NULL;
574 rndis->port.out_ep->desc = NULL;
575 goto fail;
576 }
577 }
578
579 /* Avoid ZLPs; they can be troublesome. */
580 rndis->port.is_zlp_ok = false;
581
582 /* RNDIS should be in the "RNDIS uninitialized" state,
583 * either never activated or after rndis_uninit().
584 *
585 * We don't want data to flow here until a nonzero packet
586 * filter is set, at which point it enters "RNDIS data
587 * initialized" state ... but we do want the endpoints
588 * to be activated. It's a strange little state.
589 *
590 * REVISIT the RNDIS gadget code has done this wrong for a
591 * very long time. We need another call to the link layer
592 * code -- gether_updown(...bool) maybe -- to do it right.
593 */
594 rndis->port.cdc_filter = 0;
595
596 DBG(cdev, "RNDIS RX/TX early activation ... \n");
597 net = gether_connect(&rndis->port);
598 if (IS_ERR(net))
599 return PTR_ERR(net);
600
601 rndis_set_param_dev(rndis->params, net,
602 &rndis->port.cdc_filter);
603 } else
604 goto fail;
605
606 return 0;
607fail:
608 return -EINVAL;
609}
610
611static void rndis_disable(struct usb_function *f)
612{
613 struct f_rndis *rndis = func_to_rndis(f);
614 struct usb_composite_dev *cdev = f->config->cdev;
615
616 if (!rndis->notify->enabled)
617 return;
618
619 DBG(cdev, "rndis deactivated\n");
620
621 rndis_uninit(rndis->params);
622 gether_disconnect(&rndis->port);
623
624 usb_ep_disable(rndis->notify);
625}
626
627/*-------------------------------------------------------------------------*/
628
629/*
630 * This isn't quite the same mechanism as CDC Ethernet, since the
631 * notification scheme passes less data, but the same set of link
632 * states must be tested. A key difference is that altsettings are
633 * not used to tell whether the link should send packets or not.
634 */
635
636static void rndis_open(struct gether *geth)
637{
638 struct f_rndis *rndis = func_to_rndis(&geth->func);
639 struct usb_composite_dev *cdev = geth->func.config->cdev;
640
641 DBG(cdev, "%s\n", __func__);
642
643 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3,
644 bitrate(cdev->gadget) / 100);
645 rndis_signal_connect(rndis->params);
646}
647
648static void rndis_close(struct gether *geth)
649{
650 struct f_rndis *rndis = func_to_rndis(&geth->func);
651
652 DBG(geth->func.config->cdev, "%s\n", __func__);
653
654 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
655 rndis_signal_disconnect(rndis->params);
656}
657
658/*-------------------------------------------------------------------------*/
659
660/* Some controllers can't support RNDIS ... */
661static inline bool can_support_rndis(struct usb_configuration *c)
662{
663 /* everything else is *presumably* fine */
664 return true;
665}
666
667/* ethernet function driver setup/binding */
668
669static int
670rndis_bind(struct usb_configuration *c, struct usb_function *f)
671{
672 struct usb_composite_dev *cdev = c->cdev;
673 struct f_rndis *rndis = func_to_rndis(f);
674 struct usb_string *us;
675 int status;
676 struct usb_ep *ep;
677
678 struct f_rndis_opts *rndis_opts;
679
680 if (!can_support_rndis(c))
681 return -EINVAL;
682
683 rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst);
684
685 if (cdev->use_os_string) {
686 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
687 GFP_KERNEL);
688 if (!f->os_desc_table)
689 return -ENOMEM;
690 f->os_desc_n = 1;
691 f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc;
692 }
693
694 /*
695 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
696 * configurations are bound in sequence with list_for_each_entry,
697 * in each configuration its functions are bound in sequence
698 * with list_for_each_entry, so we assume no race condition
699 * with regard to rndis_opts->bound access
700 */
701 if (!rndis_opts->bound) {
702 gether_set_gadget(rndis_opts->net, cdev->gadget);
703 status = gether_register_netdev(rndis_opts->net);
704 if (status)
705 goto fail;
706 rndis_opts->bound = true;
707 }
708
709 us = usb_gstrings_attach(cdev, rndis_strings,
710 ARRAY_SIZE(rndis_string_defs));
711 if (IS_ERR(us)) {
712 status = PTR_ERR(us);
713 goto fail;
714 }
715 rndis_control_intf.iInterface = us[0].id;
716 rndis_data_intf.iInterface = us[1].id;
717 rndis_iad_descriptor.iFunction = us[2].id;
718
719 /* allocate instance-specific interface IDs */
720 status = usb_interface_id(c, f);
721 if (status < 0)
722 goto fail;
723 rndis->ctrl_id = status;
724 rndis_iad_descriptor.bFirstInterface = status;
725
726 rndis_control_intf.bInterfaceNumber = status;
727 rndis_union_desc.bMasterInterface0 = status;
728
729 if (cdev->use_os_string)
730 f->os_desc_table[0].if_id =
731 rndis_iad_descriptor.bFirstInterface;
732
733 status = usb_interface_id(c, f);
734 if (status < 0)
735 goto fail;
736 rndis->data_id = status;
737
738 rndis_data_intf.bInterfaceNumber = status;
739 rndis_union_desc.bSlaveInterface0 = status;
740
741 status = -ENODEV;
742
743 /* allocate instance-specific endpoints */
744 ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
745 if (!ep)
746 goto fail;
747 rndis->port.in_ep = ep;
748
749 ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
750 if (!ep)
751 goto fail;
752 rndis->port.out_ep = ep;
753
754 /* NOTE: a status/notification endpoint is, strictly speaking,
755 * optional. We don't treat it that way though! It's simpler,
756 * and some newer profiles don't treat it as optional.
757 */
758 ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
759 if (!ep)
760 goto fail;
761 rndis->notify = ep;
762
763 status = -ENOMEM;
764
765 /* allocate notification request and buffer */
766 rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
767 if (!rndis->notify_req)
768 goto fail;
769 rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
770 if (!rndis->notify_req->buf)
771 goto fail;
772 rndis->notify_req->length = STATUS_BYTECOUNT;
773 rndis->notify_req->context = rndis;
774 rndis->notify_req->complete = rndis_response_complete;
775
776 /* support all relevant hardware speeds... we expect that when
777 * hardware is dual speed, all bulk-capable endpoints work at
778 * both speeds
779 */
780 hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
781 hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
782 hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
783
784 ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
785 ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
786 ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
787
788 status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function,
789 eth_ss_function, NULL);
790 if (status)
791 goto fail;
792
793 rndis->port.open = rndis_open;
794 rndis->port.close = rndis_close;
795
796 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
797 rndis_set_host_mac(rndis->params, rndis->ethaddr);
798
799 if (rndis->manufacturer && rndis->vendorID &&
800 rndis_set_param_vendor(rndis->params, rndis->vendorID,
801 rndis->manufacturer)) {
802 status = -EINVAL;
803 goto fail_free_descs;
804 }
805
806 /* NOTE: all that is done without knowing or caring about
807 * the network link ... which is unavailable to this code
808 * until we're activated via set_alt().
809 */
810
811 DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
812 gadget_is_superspeed(c->cdev->gadget) ? "super" :
813 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
814 rndis->port.in_ep->name, rndis->port.out_ep->name,
815 rndis->notify->name);
816 return 0;
817
818fail_free_descs:
819 usb_free_all_descriptors(f);
820fail:
821 kfree(f->os_desc_table);
822 f->os_desc_n = 0;
823
824 if (rndis->notify_req) {
825 kfree(rndis->notify_req->buf);
826 usb_ep_free_request(rndis->notify, rndis->notify_req);
827 }
828
829 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
830
831 return status;
832}
833
834void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net)
835{
836 struct f_rndis_opts *opts;
837
838 opts = container_of(f, struct f_rndis_opts, func_inst);
839 if (opts->bound)
840 gether_cleanup(netdev_priv(opts->net));
841 else
842 free_netdev(opts->net);
843 opts->borrowed_net = opts->bound = true;
844 opts->net = net;
845}
846EXPORT_SYMBOL_GPL(rndis_borrow_net);
847
848static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item)
849{
850 return container_of(to_config_group(item), struct f_rndis_opts,
851 func_inst.group);
852}
853
854/* f_rndis_item_ops */
855USB_ETHERNET_CONFIGFS_ITEM(rndis);
856
857/* f_rndis_opts_dev_addr */
858USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis);
859
860/* f_rndis_opts_host_addr */
861USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis);
862
863/* f_rndis_opts_qmult */
864USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis);
865
866/* f_rndis_opts_ifname */
867USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis);
868
869static struct configfs_attribute *rndis_attrs[] = {
870 &rndis_opts_attr_dev_addr,
871 &rndis_opts_attr_host_addr,
872 &rndis_opts_attr_qmult,
873 &rndis_opts_attr_ifname,
874 NULL,
875};
876
877static struct config_item_type rndis_func_type = {
878 .ct_item_ops = &rndis_item_ops,
879 .ct_attrs = rndis_attrs,
880 .ct_owner = THIS_MODULE,
881};
882
883static void rndis_free_inst(struct usb_function_instance *f)
884{
885 struct f_rndis_opts *opts;
886
887 opts = container_of(f, struct f_rndis_opts, func_inst);
888 if (!opts->borrowed_net) {
889 if (opts->bound)
890 gether_cleanup(netdev_priv(opts->net));
891 else
892 free_netdev(opts->net);
893 }
894
895 kfree(opts);
896}
897
898static struct usb_function_instance *rndis_alloc_inst(void)
899{
900 struct f_rndis_opts *opts;
901 struct usb_os_desc *descs[1];
902 char *names[1];
903
904 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
905 if (!opts)
906 return ERR_PTR(-ENOMEM);
907 opts->rndis_os_desc.ext_compat_id = opts->rndis_ext_compat_id;
908
909 mutex_init(&opts->lock);
910 opts->func_inst.free_func_inst = rndis_free_inst;
911 opts->net = gether_setup_default();
912 if (IS_ERR(opts->net)) {
913 struct net_device *net = opts->net;
914 kfree(opts);
915 return ERR_CAST(net);
916 }
917 INIT_LIST_HEAD(&opts->rndis_os_desc.ext_prop);
918
919 descs[0] = &opts->rndis_os_desc;
920 names[0] = "rndis";
921 config_group_init_type_name(&opts->func_inst.group, "",
922 &rndis_func_type);
923 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
924 names, THIS_MODULE);
925
926 return &opts->func_inst;
927}
928
929static void rndis_free(struct usb_function *f)
930{
931 struct f_rndis *rndis;
932 struct f_rndis_opts *opts;
933
934 rndis = func_to_rndis(f);
935 rndis_deregister(rndis->params);
936 opts = container_of(f->fi, struct f_rndis_opts, func_inst);
937 kfree(rndis);
938 mutex_lock(&opts->lock);
939 opts->refcnt--;
940 mutex_unlock(&opts->lock);
941}
942
943static void rndis_unbind(struct usb_configuration *c, struct usb_function *f)
944{
945 struct f_rndis *rndis = func_to_rndis(f);
946
947 kfree(f->os_desc_table);
948 f->os_desc_n = 0;
949 usb_free_all_descriptors(f);
950
951 kfree(rndis->notify_req->buf);
952 usb_ep_free_request(rndis->notify, rndis->notify_req);
953}
954
955static struct usb_function *rndis_alloc(struct usb_function_instance *fi)
956{
957 struct f_rndis *rndis;
958 struct f_rndis_opts *opts;
959 struct rndis_params *params;
960
961 /* allocate and initialize one new instance */
962 rndis = kzalloc(sizeof(*rndis), GFP_KERNEL);
963 if (!rndis)
964 return ERR_PTR(-ENOMEM);
965
966 opts = container_of(fi, struct f_rndis_opts, func_inst);
967 mutex_lock(&opts->lock);
968 opts->refcnt++;
969
970 gether_get_host_addr_u8(opts->net, rndis->ethaddr);
971 rndis->vendorID = opts->vendor_id;
972 rndis->manufacturer = opts->manufacturer;
973
974 rndis->port.ioport = netdev_priv(opts->net);
975 mutex_unlock(&opts->lock);
976 /* RNDIS activates when the host changes this filter */
977 rndis->port.cdc_filter = 0;
978
979 /* RNDIS has special (and complex) framing */
980 rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
981 rndis->port.wrap = rndis_add_header;
982 rndis->port.unwrap = rndis_rm_hdr;
983
984 rndis->port.func.name = "rndis";
985 /* descriptors are per-instance copies */
986 rndis->port.func.bind = rndis_bind;
987 rndis->port.func.unbind = rndis_unbind;
988 rndis->port.func.set_alt = rndis_set_alt;
989 rndis->port.func.setup = rndis_setup;
990 rndis->port.func.disable = rndis_disable;
991 rndis->port.func.free_func = rndis_free;
992
993 params = rndis_register(rndis_response_available, rndis);
994 if (IS_ERR(params)) {
995 kfree(rndis);
996 return ERR_CAST(params);
997 }
998 rndis->params = params;
999
1000 return &rndis->port.func;
1001}
1002
1003DECLARE_USB_FUNCTION_INIT(rndis, rndis_alloc_inst, rndis_alloc);
1004MODULE_LICENSE("GPL");
1005MODULE_AUTHOR("David Brownell");