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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 skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
378 rndis_add_hdr(skb2);
379
380 dev_kfree_skb(skb);
381 return skb2;
382}
383
384static void rndis_response_available(void *_rndis)
385{
386 struct f_rndis *rndis = _rndis;
387 struct usb_request *req = rndis->notify_req;
388 struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
389 __le32 *data = req->buf;
390 int status;
391
392 if (atomic_inc_return(&rndis->notify_count) != 1)
393 return;
394
395 /* Send RNDIS RESPONSE_AVAILABLE notification; a
396 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too
397 *
398 * This is the only notification defined by RNDIS.
399 */
400 data[0] = cpu_to_le32(1);
401 data[1] = cpu_to_le32(0);
402
403 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
404 if (status) {
405 atomic_dec(&rndis->notify_count);
406 DBG(cdev, "notify/0 --> %d\n", status);
407 }
408}
409
410static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
411{
412 struct f_rndis *rndis = req->context;
413 struct usb_composite_dev *cdev = rndis->port.func.config->cdev;
414 int status = req->status;
415
416 /* after TX:
417 * - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control)
418 * - RNDIS_RESPONSE_AVAILABLE (status/irq)
419 */
420 switch (status) {
421 case -ECONNRESET:
422 case -ESHUTDOWN:
423 /* connection gone */
424 atomic_set(&rndis->notify_count, 0);
425 break;
426 default:
427 DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
428 ep->name, status,
429 req->actual, req->length);
430 /* FALLTHROUGH */
431 case 0:
432 if (ep != rndis->notify)
433 break;
434
435 /* handle multiple pending RNDIS_RESPONSE_AVAILABLE
436 * notifications by resending until we're done
437 */
438 if (atomic_dec_and_test(&rndis->notify_count))
439 break;
440 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
441 if (status) {
442 atomic_dec(&rndis->notify_count);
443 DBG(cdev, "notify/1 --> %d\n", status);
444 }
445 break;
446 }
447}
448
449static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req)
450{
451 struct f_rndis *rndis = req->context;
452 int status;
453
454 /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */
455// spin_lock(&dev->lock);
456 status = rndis_msg_parser(rndis->params, (u8 *) req->buf);
457 if (status < 0)
458 pr_err("RNDIS command error %d, %d/%d\n",
459 status, req->actual, req->length);
460// spin_unlock(&dev->lock);
461}
462
463static int
464rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
465{
466 struct f_rndis *rndis = func_to_rndis(f);
467 struct usb_composite_dev *cdev = f->config->cdev;
468 struct usb_request *req = cdev->req;
469 int value = -EOPNOTSUPP;
470 u16 w_index = le16_to_cpu(ctrl->wIndex);
471 u16 w_value = le16_to_cpu(ctrl->wValue);
472 u16 w_length = le16_to_cpu(ctrl->wLength);
473
474 /* composite driver infrastructure handles everything except
475 * CDC class messages; interface activation uses set_alt().
476 */
477 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
478
479 /* RNDIS uses the CDC command encapsulation mechanism to implement
480 * an RPC scheme, with much getting/setting of attributes by OID.
481 */
482 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
483 | USB_CDC_SEND_ENCAPSULATED_COMMAND:
484 if (w_value || w_index != rndis->ctrl_id)
485 goto invalid;
486 /* read the request; process it later */
487 value = w_length;
488 req->complete = rndis_command_complete;
489 req->context = rndis;
490 /* later, rndis_response_available() sends a notification */
491 break;
492
493 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
494 | USB_CDC_GET_ENCAPSULATED_RESPONSE:
495 if (w_value || w_index != rndis->ctrl_id)
496 goto invalid;
497 else {
498 u8 *buf;
499 u32 n;
500
501 /* return the result */
502 buf = rndis_get_next_response(rndis->params, &n);
503 if (buf) {
504 memcpy(req->buf, buf, n);
505 req->complete = rndis_response_complete;
506 req->context = rndis;
507 rndis_free_response(rndis->params, buf);
508 value = n;
509 }
510 /* else stalls ... spec says to avoid that */
511 }
512 break;
513
514 default:
515invalid:
516 VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
517 ctrl->bRequestType, ctrl->bRequest,
518 w_value, w_index, w_length);
519 }
520
521 /* respond with data transfer or status phase? */
522 if (value >= 0) {
523 DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n",
524 ctrl->bRequestType, ctrl->bRequest,
525 w_value, w_index, w_length);
526 req->zero = (value < w_length);
527 req->length = value;
528 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
529 if (value < 0)
530 ERROR(cdev, "rndis response on err %d\n", value);
531 }
532
533 /* device either stalls (value < 0) or reports success */
534 return value;
535}
536
537
538static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
539{
540 struct f_rndis *rndis = func_to_rndis(f);
541 struct usb_composite_dev *cdev = f->config->cdev;
542
543 /* we know alt == 0 */
544
545 if (intf == rndis->ctrl_id) {
546 VDBG(cdev, "reset rndis control %d\n", intf);
547 usb_ep_disable(rndis->notify);
548
549 if (!rndis->notify->desc) {
550 VDBG(cdev, "init rndis ctrl %d\n", intf);
551 if (config_ep_by_speed(cdev->gadget, f, rndis->notify))
552 goto fail;
553 }
554 usb_ep_enable(rndis->notify);
555
556 } else if (intf == rndis->data_id) {
557 struct net_device *net;
558
559 if (rndis->port.in_ep->enabled) {
560 DBG(cdev, "reset rndis\n");
561 gether_disconnect(&rndis->port);
562 }
563
564 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) {
565 DBG(cdev, "init rndis\n");
566 if (config_ep_by_speed(cdev->gadget, f,
567 rndis->port.in_ep) ||
568 config_ep_by_speed(cdev->gadget, f,
569 rndis->port.out_ep)) {
570 rndis->port.in_ep->desc = NULL;
571 rndis->port.out_ep->desc = NULL;
572 goto fail;
573 }
574 }
575
576 /* Avoid ZLPs; they can be troublesome. */
577 rndis->port.is_zlp_ok = false;
578
579 /* RNDIS should be in the "RNDIS uninitialized" state,
580 * either never activated or after rndis_uninit().
581 *
582 * We don't want data to flow here until a nonzero packet
583 * filter is set, at which point it enters "RNDIS data
584 * initialized" state ... but we do want the endpoints
585 * to be activated. It's a strange little state.
586 *
587 * REVISIT the RNDIS gadget code has done this wrong for a
588 * very long time. We need another call to the link layer
589 * code -- gether_updown(...bool) maybe -- to do it right.
590 */
591 rndis->port.cdc_filter = 0;
592
593 DBG(cdev, "RNDIS RX/TX early activation ... \n");
594 net = gether_connect(&rndis->port);
595 if (IS_ERR(net))
596 return PTR_ERR(net);
597
598 rndis_set_param_dev(rndis->params, net,
599 &rndis->port.cdc_filter);
600 } else
601 goto fail;
602
603 return 0;
604fail:
605 return -EINVAL;
606}
607
608static void rndis_disable(struct usb_function *f)
609{
610 struct f_rndis *rndis = func_to_rndis(f);
611 struct usb_composite_dev *cdev = f->config->cdev;
612
613 if (!rndis->notify->enabled)
614 return;
615
616 DBG(cdev, "rndis deactivated\n");
617
618 rndis_uninit(rndis->params);
619 gether_disconnect(&rndis->port);
620
621 usb_ep_disable(rndis->notify);
622}
623
624/*-------------------------------------------------------------------------*/
625
626/*
627 * This isn't quite the same mechanism as CDC Ethernet, since the
628 * notification scheme passes less data, but the same set of link
629 * states must be tested. A key difference is that altsettings are
630 * not used to tell whether the link should send packets or not.
631 */
632
633static void rndis_open(struct gether *geth)
634{
635 struct f_rndis *rndis = func_to_rndis(&geth->func);
636 struct usb_composite_dev *cdev = geth->func.config->cdev;
637
638 DBG(cdev, "%s\n", __func__);
639
640 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3,
641 bitrate(cdev->gadget) / 100);
642 rndis_signal_connect(rndis->params);
643}
644
645static void rndis_close(struct gether *geth)
646{
647 struct f_rndis *rndis = func_to_rndis(&geth->func);
648
649 DBG(geth->func.config->cdev, "%s\n", __func__);
650
651 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
652 rndis_signal_disconnect(rndis->params);
653}
654
655/*-------------------------------------------------------------------------*/
656
657/* Some controllers can't support RNDIS ... */
658static inline bool can_support_rndis(struct usb_configuration *c)
659{
660 /* everything else is *presumably* fine */
661 return true;
662}
663
664/* ethernet function driver setup/binding */
665
666static int
667rndis_bind(struct usb_configuration *c, struct usb_function *f)
668{
669 struct usb_composite_dev *cdev = c->cdev;
670 struct f_rndis *rndis = func_to_rndis(f);
671 struct usb_string *us;
672 int status;
673 struct usb_ep *ep;
674
675 struct f_rndis_opts *rndis_opts;
676
677 if (!can_support_rndis(c))
678 return -EINVAL;
679
680 rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst);
681
682 if (cdev->use_os_string) {
683 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
684 GFP_KERNEL);
685 if (!f->os_desc_table)
686 return -ENOMEM;
687 f->os_desc_n = 1;
688 f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc;
689 }
690
691 /*
692 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
693 * configurations are bound in sequence with list_for_each_entry,
694 * in each configuration its functions are bound in sequence
695 * with list_for_each_entry, so we assume no race condition
696 * with regard to rndis_opts->bound access
697 */
698 if (!rndis_opts->bound) {
699 gether_set_gadget(rndis_opts->net, cdev->gadget);
700 status = gether_register_netdev(rndis_opts->net);
701 if (status)
702 goto fail;
703 rndis_opts->bound = true;
704 }
705
706 us = usb_gstrings_attach(cdev, rndis_strings,
707 ARRAY_SIZE(rndis_string_defs));
708 if (IS_ERR(us)) {
709 status = PTR_ERR(us);
710 goto fail;
711 }
712 rndis_control_intf.iInterface = us[0].id;
713 rndis_data_intf.iInterface = us[1].id;
714 rndis_iad_descriptor.iFunction = us[2].id;
715
716 /* allocate instance-specific interface IDs */
717 status = usb_interface_id(c, f);
718 if (status < 0)
719 goto fail;
720 rndis->ctrl_id = status;
721 rndis_iad_descriptor.bFirstInterface = status;
722
723 rndis_control_intf.bInterfaceNumber = status;
724 rndis_union_desc.bMasterInterface0 = status;
725
726 if (cdev->use_os_string)
727 f->os_desc_table[0].if_id =
728 rndis_iad_descriptor.bFirstInterface;
729
730 status = usb_interface_id(c, f);
731 if (status < 0)
732 goto fail;
733 rndis->data_id = status;
734
735 rndis_data_intf.bInterfaceNumber = status;
736 rndis_union_desc.bSlaveInterface0 = status;
737
738 status = -ENODEV;
739
740 /* allocate instance-specific endpoints */
741 ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
742 if (!ep)
743 goto fail;
744 rndis->port.in_ep = ep;
745
746 ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
747 if (!ep)
748 goto fail;
749 rndis->port.out_ep = ep;
750
751 /* NOTE: a status/notification endpoint is, strictly speaking,
752 * optional. We don't treat it that way though! It's simpler,
753 * and some newer profiles don't treat it as optional.
754 */
755 ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
756 if (!ep)
757 goto fail;
758 rndis->notify = ep;
759
760 status = -ENOMEM;
761
762 /* allocate notification request and buffer */
763 rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
764 if (!rndis->notify_req)
765 goto fail;
766 rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
767 if (!rndis->notify_req->buf)
768 goto fail;
769 rndis->notify_req->length = STATUS_BYTECOUNT;
770 rndis->notify_req->context = rndis;
771 rndis->notify_req->complete = rndis_response_complete;
772
773 /* support all relevant hardware speeds... we expect that when
774 * hardware is dual speed, all bulk-capable endpoints work at
775 * both speeds
776 */
777 hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
778 hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
779 hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
780
781 ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
782 ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
783 ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
784
785 status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function,
786 eth_ss_function, NULL);
787 if (status)
788 goto fail;
789
790 rndis->port.open = rndis_open;
791 rndis->port.close = rndis_close;
792
793 rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
794 rndis_set_host_mac(rndis->params, rndis->ethaddr);
795
796 if (rndis->manufacturer && rndis->vendorID &&
797 rndis_set_param_vendor(rndis->params, rndis->vendorID,
798 rndis->manufacturer)) {
799 status = -EINVAL;
800 goto fail_free_descs;
801 }
802
803 /* NOTE: all that is done without knowing or caring about
804 * the network link ... which is unavailable to this code
805 * until we're activated via set_alt().
806 */
807
808 DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
809 gadget_is_superspeed(c->cdev->gadget) ? "super" :
810 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
811 rndis->port.in_ep->name, rndis->port.out_ep->name,
812 rndis->notify->name);
813 return 0;
814
815fail_free_descs:
816 usb_free_all_descriptors(f);
817fail:
818 kfree(f->os_desc_table);
819 f->os_desc_n = 0;
820
821 if (rndis->notify_req) {
822 kfree(rndis->notify_req->buf);
823 usb_ep_free_request(rndis->notify, rndis->notify_req);
824 }
825
826 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
827
828 return status;
829}
830
831void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net)
832{
833 struct f_rndis_opts *opts;
834
835 opts = container_of(f, struct f_rndis_opts, func_inst);
836 if (opts->bound)
837 gether_cleanup(netdev_priv(opts->net));
838 else
839 free_netdev(opts->net);
840 opts->borrowed_net = opts->bound = true;
841 opts->net = net;
842}
843EXPORT_SYMBOL_GPL(rndis_borrow_net);
844
845static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item)
846{
847 return container_of(to_config_group(item), struct f_rndis_opts,
848 func_inst.group);
849}
850
851/* f_rndis_item_ops */
852USB_ETHERNET_CONFIGFS_ITEM(rndis);
853
854/* f_rndis_opts_dev_addr */
855USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis);
856
857/* f_rndis_opts_host_addr */
858USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis);
859
860/* f_rndis_opts_qmult */
861USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis);
862
863/* f_rndis_opts_ifname */
864USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis);
865
866static struct configfs_attribute *rndis_attrs[] = {
867 &rndis_opts_attr_dev_addr,
868 &rndis_opts_attr_host_addr,
869 &rndis_opts_attr_qmult,
870 &rndis_opts_attr_ifname,
871 NULL,
872};
873
874static struct config_item_type rndis_func_type = {
875 .ct_item_ops = &rndis_item_ops,
876 .ct_attrs = rndis_attrs,
877 .ct_owner = THIS_MODULE,
878};
879
880static void rndis_free_inst(struct usb_function_instance *f)
881{
882 struct f_rndis_opts *opts;
883
884 opts = container_of(f, struct f_rndis_opts, func_inst);
885 if (!opts->borrowed_net) {
886 if (opts->bound)
887 gether_cleanup(netdev_priv(opts->net));
888 else
889 free_netdev(opts->net);
890 }
891
892 kfree(opts);
893}
894
895static struct usb_function_instance *rndis_alloc_inst(void)
896{
897 struct f_rndis_opts *opts;
898 struct usb_os_desc *descs[1];
899 char *names[1];
900
901 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
902 if (!opts)
903 return ERR_PTR(-ENOMEM);
904 opts->rndis_os_desc.ext_compat_id = opts->rndis_ext_compat_id;
905
906 mutex_init(&opts->lock);
907 opts->func_inst.free_func_inst = rndis_free_inst;
908 opts->net = gether_setup_default();
909 if (IS_ERR(opts->net)) {
910 struct net_device *net = opts->net;
911 kfree(opts);
912 return ERR_CAST(net);
913 }
914 INIT_LIST_HEAD(&opts->rndis_os_desc.ext_prop);
915
916 descs[0] = &opts->rndis_os_desc;
917 names[0] = "rndis";
918 config_group_init_type_name(&opts->func_inst.group, "",
919 &rndis_func_type);
920 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
921 names, THIS_MODULE);
922
923 return &opts->func_inst;
924}
925
926static void rndis_free(struct usb_function *f)
927{
928 struct f_rndis *rndis;
929 struct f_rndis_opts *opts;
930
931 rndis = func_to_rndis(f);
932 rndis_deregister(rndis->params);
933 opts = container_of(f->fi, struct f_rndis_opts, func_inst);
934 kfree(rndis);
935 mutex_lock(&opts->lock);
936 opts->refcnt--;
937 mutex_unlock(&opts->lock);
938}
939
940static void rndis_unbind(struct usb_configuration *c, struct usb_function *f)
941{
942 struct f_rndis *rndis = func_to_rndis(f);
943
944 kfree(f->os_desc_table);
945 f->os_desc_n = 0;
946 usb_free_all_descriptors(f);
947
948 kfree(rndis->notify_req->buf);
949 usb_ep_free_request(rndis->notify, rndis->notify_req);
950}
951
952static struct usb_function *rndis_alloc(struct usb_function_instance *fi)
953{
954 struct f_rndis *rndis;
955 struct f_rndis_opts *opts;
956 struct rndis_params *params;
957
958 /* allocate and initialize one new instance */
959 rndis = kzalloc(sizeof(*rndis), GFP_KERNEL);
960 if (!rndis)
961 return ERR_PTR(-ENOMEM);
962
963 opts = container_of(fi, struct f_rndis_opts, func_inst);
964 mutex_lock(&opts->lock);
965 opts->refcnt++;
966
967 gether_get_host_addr_u8(opts->net, rndis->ethaddr);
968 rndis->vendorID = opts->vendor_id;
969 rndis->manufacturer = opts->manufacturer;
970
971 rndis->port.ioport = netdev_priv(opts->net);
972 mutex_unlock(&opts->lock);
973 /* RNDIS activates when the host changes this filter */
974 rndis->port.cdc_filter = 0;
975
976 /* RNDIS has special (and complex) framing */
977 rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
978 rndis->port.wrap = rndis_add_header;
979 rndis->port.unwrap = rndis_rm_hdr;
980
981 rndis->port.func.name = "rndis";
982 /* descriptors are per-instance copies */
983 rndis->port.func.bind = rndis_bind;
984 rndis->port.func.unbind = rndis_unbind;
985 rndis->port.func.set_alt = rndis_set_alt;
986 rndis->port.func.setup = rndis_setup;
987 rndis->port.func.disable = rndis_disable;
988 rndis->port.func.free_func = rndis_free;
989
990 params = rndis_register(rndis_response_available, rndis);
991 if (IS_ERR(params)) {
992 kfree(rndis);
993 return ERR_CAST(params);
994 }
995 rndis->params = params;
996
997 return &rndis->port.func;
998}
999
1000DECLARE_USB_FUNCTION_INIT(rndis, rndis_alloc_inst, rndis_alloc);
1001MODULE_LICENSE("GPL");
1002MODULE_AUTHOR("David Brownell");