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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
31/*
32 * This function is an RNDIS Ethernet port -- a Microsoft protocol that's
33 * been promoted instead of the standard CDC Ethernet. The published RNDIS
34 * spec is ambiguous, incomplete, and needlessly complex. Variants such as
35 * ActiveSync have even worse status in terms of specification.
36 *
37 * In short: it's a protocol controlled by (and for) Microsoft, not for an
38 * Open ecosystem or markets. Linux supports it *only* because Microsoft
39 * doesn't support the CDC Ethernet standard.
40 *
41 * The RNDIS data transfer model is complex, with multiple Ethernet packets
42 * per USB message, and out of band data. The control model is built around
43 * what's essentially an "RNDIS RPC" protocol. It's all wrapped in a CDC ACM
44 * (modem, not Ethernet) veneer, with those ACM descriptors being entirely
45 * useless (they're ignored). RNDIS expects to be the only function in its
46 * configuration, so it's no real help if you need composite devices; and
47 * it expects to be the first configuration too.
48 *
49 * There is a single technical advantage of RNDIS over CDC Ethernet, if you
50 * discount the fluff that its RPC can be made to deliver: it doesn't need
51 * a NOP altsetting for the data interface. That lets it work on some of the
52 * "so smart it's stupid" hardware which takes over configuration changes
53 * from the software, and adds restrictions like "no altsettings".
54 *
55 * Unfortunately MSFT's RNDIS drivers are buggy. They hang or oops, and
56 * have all sorts of contrary-to-specification oddities that can prevent
57 * them from working sanely. Since bugfixes (or accurate specs, letting
58 * Linux work around those bugs) are unlikely to ever come from MSFT, you
59 * may want to avoid using RNDIS on purely operational grounds.
60 *
61 * Omissions from the RNDIS 1.0 specification include:
62 *
63 * - Power management ... references data that's scattered around lots
64 * of other documentation, which is incorrect/incomplete there too.
65 *
66 * - There are various undocumented protocol requirements, like the need
67 * to send garbage in some control-OUT messages.
68 *
69 * - MS-Windows drivers sometimes emit undocumented requests.
70 */
71
72struct f_rndis {
73 struct gether port;
74 u8 ctrl_id, data_id;
75 u8 ethaddr[ETH_ALEN];
76 u32 vendorID;
77 const char *manufacturer;
78 int config;
79
80 struct usb_ep *notify;
81 struct usb_request *notify_req;
82 atomic_t notify_count;
83};
84
85static inline struct f_rndis *func_to_rndis(struct usb_function *f)
86{
87 return container_of(f, struct f_rndis, port.func);
88}
89
90/* peak (theoretical) bulk transfer rate in bits-per-second */
91static unsigned int bitrate(struct usb_gadget *g)
92{
93 if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
94 return 13 * 1024 * 8 * 1000 * 8;
95 else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
96 return 13 * 512 * 8 * 1000 * 8;
97 else
98 return 19 * 64 * 1 * 1000 * 8;
99}
100
101/*-------------------------------------------------------------------------*/
102
103/*
104 */
105
106#define RNDIS_STATUS_INTERVAL_MS 32
107#define STATUS_BYTECOUNT 8 /* 8 bytes data */
108
109
110/* interface descriptor: */
111
112static struct usb_interface_descriptor rndis_control_intf = {
113 .bLength = sizeof rndis_control_intf,
114 .bDescriptorType = USB_DT_INTERFACE,
115
116 /* .bInterfaceNumber = DYNAMIC */
117 /* status endpoint is optional; this could be patched later */
118 .bNumEndpoints = 1,
119 .bInterfaceClass = USB_CLASS_COMM,
120 .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
121 .bInterfaceProtocol = USB_CDC_ACM_PROTO_VENDOR,
122 /* .iInterface = DYNAMIC */
123};
124
125static struct usb_cdc_header_desc header_desc = {
126 .bLength = sizeof header_desc,
127 .bDescriptorType = USB_DT_CS_INTERFACE,
128 .bDescriptorSubType = USB_CDC_HEADER_TYPE,
129
130 .bcdCDC = cpu_to_le16(0x0110),
131};
132
133static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = {
134 .bLength = sizeof call_mgmt_descriptor,
135 .bDescriptorType = USB_DT_CS_INTERFACE,
136 .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE,
137
138 .bmCapabilities = 0x00,
139 .bDataInterface = 0x01,
140};
141
142static struct usb_cdc_acm_descriptor rndis_acm_descriptor = {
143 .bLength = sizeof rndis_acm_descriptor,
144 .bDescriptorType = USB_DT_CS_INTERFACE,
145 .bDescriptorSubType = USB_CDC_ACM_TYPE,
146
147 .bmCapabilities = 0x00,
148};
149
150static struct usb_cdc_union_desc rndis_union_desc = {
151 .bLength = sizeof(rndis_union_desc),
152 .bDescriptorType = USB_DT_CS_INTERFACE,
153 .bDescriptorSubType = USB_CDC_UNION_TYPE,
154 /* .bMasterInterface0 = DYNAMIC */
155 /* .bSlaveInterface0 = DYNAMIC */
156};
157
158/* the data interface has two bulk endpoints */
159
160static struct usb_interface_descriptor rndis_data_intf = {
161 .bLength = sizeof rndis_data_intf,
162 .bDescriptorType = USB_DT_INTERFACE,
163
164 /* .bInterfaceNumber = DYNAMIC */
165 .bNumEndpoints = 2,
166 .bInterfaceClass = USB_CLASS_CDC_DATA,
167 .bInterfaceSubClass = 0,
168 .bInterfaceProtocol = 0,
169 /* .iInterface = DYNAMIC */
170};
171
172
173static struct usb_interface_assoc_descriptor
174rndis_iad_descriptor = {
175 .bLength = sizeof rndis_iad_descriptor,
176 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
177
178 .bFirstInterface = 0, /* XXX, hardcoded */
179 .bInterfaceCount = 2, // control + data
180 .bFunctionClass = USB_CLASS_COMM,
181 .bFunctionSubClass = USB_CDC_SUBCLASS_ETHERNET,
182 .bFunctionProtocol = USB_CDC_PROTO_NONE,
183 /* .iFunction = DYNAMIC */
184};
185
186/* full speed support: */
187
188static struct usb_endpoint_descriptor fs_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(STATUS_BYTECOUNT),
195 .bInterval = RNDIS_STATUS_INTERVAL_MS,
196};
197
198static struct usb_endpoint_descriptor fs_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
206static struct usb_endpoint_descriptor fs_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
214static struct usb_descriptor_header *eth_fs_function[] = {
215 (struct usb_descriptor_header *) &rndis_iad_descriptor,
216
217 /* control interface matches ACM, not Ethernet */
218 (struct usb_descriptor_header *) &rndis_control_intf,
219 (struct usb_descriptor_header *) &header_desc,
220 (struct usb_descriptor_header *) &call_mgmt_descriptor,
221 (struct usb_descriptor_header *) &rndis_acm_descriptor,
222 (struct usb_descriptor_header *) &rndis_union_desc,
223 (struct usb_descriptor_header *) &fs_notify_desc,
224
225 /* data interface has no altsetting */
226 (struct usb_descriptor_header *) &rndis_data_intf,
227 (struct usb_descriptor_header *) &fs_in_desc,
228 (struct usb_descriptor_header *) &fs_out_desc,
229 NULL,
230};
231
232/* high speed support: */
233
234static struct usb_endpoint_descriptor hs_notify_desc = {
235 .bLength = USB_DT_ENDPOINT_SIZE,
236 .bDescriptorType = USB_DT_ENDPOINT,
237
238 .bEndpointAddress = USB_DIR_IN,
239 .bmAttributes = USB_ENDPOINT_XFER_INT,
240 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT),
241 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
242};
243
244static struct usb_endpoint_descriptor hs_in_desc = {
245 .bLength = USB_DT_ENDPOINT_SIZE,
246 .bDescriptorType = USB_DT_ENDPOINT,
247
248 .bEndpointAddress = USB_DIR_IN,
249 .bmAttributes = USB_ENDPOINT_XFER_BULK,
250 .wMaxPacketSize = cpu_to_le16(512),
251};
252
253static struct usb_endpoint_descriptor hs_out_desc = {
254 .bLength = USB_DT_ENDPOINT_SIZE,
255 .bDescriptorType = USB_DT_ENDPOINT,
256
257 .bEndpointAddress = USB_DIR_OUT,
258 .bmAttributes = USB_ENDPOINT_XFER_BULK,
259 .wMaxPacketSize = cpu_to_le16(512),
260};
261
262static struct usb_descriptor_header *eth_hs_function[] = {
263 (struct usb_descriptor_header *) &rndis_iad_descriptor,
264
265 /* control interface matches ACM, not Ethernet */
266 (struct usb_descriptor_header *) &rndis_control_intf,
267 (struct usb_descriptor_header *) &header_desc,
268 (struct usb_descriptor_header *) &call_mgmt_descriptor,
269 (struct usb_descriptor_header *) &rndis_acm_descriptor,
270 (struct usb_descriptor_header *) &rndis_union_desc,
271 (struct usb_descriptor_header *) &hs_notify_desc,
272
273 /* data interface has no altsetting */
274 (struct usb_descriptor_header *) &rndis_data_intf,
275 (struct usb_descriptor_header *) &hs_in_desc,
276 (struct usb_descriptor_header *) &hs_out_desc,
277 NULL,
278};
279
280/* super speed support: */
281
282static struct usb_endpoint_descriptor ss_notify_desc = {
283 .bLength = USB_DT_ENDPOINT_SIZE,
284 .bDescriptorType = USB_DT_ENDPOINT,
285
286 .bEndpointAddress = USB_DIR_IN,
287 .bmAttributes = USB_ENDPOINT_XFER_INT,
288 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT),
289 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
290};
291
292static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = {
293 .bLength = sizeof ss_intr_comp_desc,
294 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
295
296 /* the following 3 values can be tweaked if necessary */
297 /* .bMaxBurst = 0, */
298 /* .bmAttributes = 0, */
299 .wBytesPerInterval = cpu_to_le16(STATUS_BYTECOUNT),
300};
301
302static struct usb_endpoint_descriptor ss_in_desc = {
303 .bLength = USB_DT_ENDPOINT_SIZE,
304 .bDescriptorType = USB_DT_ENDPOINT,
305
306 .bEndpointAddress = USB_DIR_IN,
307 .bmAttributes = USB_ENDPOINT_XFER_BULK,
308 .wMaxPacketSize = cpu_to_le16(1024),
309};
310
311static struct usb_endpoint_descriptor ss_out_desc = {
312 .bLength = USB_DT_ENDPOINT_SIZE,
313 .bDescriptorType = USB_DT_ENDPOINT,
314
315 .bEndpointAddress = USB_DIR_OUT,
316 .bmAttributes = USB_ENDPOINT_XFER_BULK,
317 .wMaxPacketSize = cpu_to_le16(1024),
318};
319
320static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = {
321 .bLength = sizeof ss_bulk_comp_desc,
322 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
323
324 /* the following 2 values can be tweaked if necessary */
325 /* .bMaxBurst = 0, */
326 /* .bmAttributes = 0, */
327};
328
329static struct usb_descriptor_header *eth_ss_function[] = {
330 (struct usb_descriptor_header *) &rndis_iad_descriptor,
331
332 /* control interface matches ACM, not Ethernet */
333 (struct usb_descriptor_header *) &rndis_control_intf,
334 (struct usb_descriptor_header *) &header_desc,
335 (struct usb_descriptor_header *) &call_mgmt_descriptor,
336 (struct usb_descriptor_header *) &rndis_acm_descriptor,
337 (struct usb_descriptor_header *) &rndis_union_desc,
338 (struct usb_descriptor_header *) &ss_notify_desc,
339 (struct usb_descriptor_header *) &ss_intr_comp_desc,
340
341 /* data interface has no altsetting */
342 (struct usb_descriptor_header *) &rndis_data_intf,
343 (struct usb_descriptor_header *) &ss_in_desc,
344 (struct usb_descriptor_header *) &ss_bulk_comp_desc,
345 (struct usb_descriptor_header *) &ss_out_desc,
346 (struct usb_descriptor_header *) &ss_bulk_comp_desc,
347 NULL,
348};
349
350/* string descriptors: */
351
352static struct usb_string rndis_string_defs[] = {
353 [0].s = "RNDIS Communications Control",
354 [1].s = "RNDIS Ethernet Data",
355 [2].s = "RNDIS",
356 { } /* end of list */
357};
358
359static struct usb_gadget_strings rndis_string_table = {
360 .language = 0x0409, /* en-us */
361 .strings = rndis_string_defs,
362};
363
364static struct usb_gadget_strings *rndis_strings[] = {
365 &rndis_string_table,
366 NULL,
367};
368
369/*-------------------------------------------------------------------------*/
370
371static struct sk_buff *rndis_add_header(struct gether *port,
372 struct sk_buff *skb)
373{
374 struct sk_buff *skb2;
375
376 skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
377 if (skb2)
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->config, (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->config, &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->config, 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 if (rndis->notify->driver_data) {
547 VDBG(cdev, "reset rndis control %d\n", intf);
548 usb_ep_disable(rndis->notify);
549 }
550 if (!rndis->notify->desc) {
551 VDBG(cdev, "init rndis ctrl %d\n", intf);
552 if (config_ep_by_speed(cdev->gadget, f, rndis->notify))
553 goto fail;
554 }
555 usb_ep_enable(rndis->notify);
556 rndis->notify->driver_data = rndis;
557
558 } else if (intf == rndis->data_id) {
559 struct net_device *net;
560
561 if (rndis->port.in_ep->driver_data) {
562 DBG(cdev, "reset rndis\n");
563 gether_disconnect(&rndis->port);
564 }
565
566 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) {
567 DBG(cdev, "init rndis\n");
568 if (config_ep_by_speed(cdev->gadget, f,
569 rndis->port.in_ep) ||
570 config_ep_by_speed(cdev->gadget, f,
571 rndis->port.out_ep)) {
572 rndis->port.in_ep->desc = NULL;
573 rndis->port.out_ep->desc = NULL;
574 goto fail;
575 }
576 }
577
578 /* Avoid ZLPs; they can be troublesome. */
579 rndis->port.is_zlp_ok = false;
580
581 /* RNDIS should be in the "RNDIS uninitialized" state,
582 * either never activated or after rndis_uninit().
583 *
584 * We don't want data to flow here until a nonzero packet
585 * filter is set, at which point it enters "RNDIS data
586 * initialized" state ... but we do want the endpoints
587 * to be activated. It's a strange little state.
588 *
589 * REVISIT the RNDIS gadget code has done this wrong for a
590 * very long time. We need another call to the link layer
591 * code -- gether_updown(...bool) maybe -- to do it right.
592 */
593 rndis->port.cdc_filter = 0;
594
595 DBG(cdev, "RNDIS RX/TX early activation ... \n");
596 net = gether_connect(&rndis->port);
597 if (IS_ERR(net))
598 return PTR_ERR(net);
599
600 rndis_set_param_dev(rndis->config, net,
601 &rndis->port.cdc_filter);
602 } else
603 goto fail;
604
605 return 0;
606fail:
607 return -EINVAL;
608}
609
610static void rndis_disable(struct usb_function *f)
611{
612 struct f_rndis *rndis = func_to_rndis(f);
613 struct usb_composite_dev *cdev = f->config->cdev;
614
615 if (!rndis->notify->driver_data)
616 return;
617
618 DBG(cdev, "rndis deactivated\n");
619
620 rndis_uninit(rndis->config);
621 gether_disconnect(&rndis->port);
622
623 usb_ep_disable(rndis->notify);
624 rndis->notify->driver_data = NULL;
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->config, RNDIS_MEDIUM_802_3,
644 bitrate(cdev->gadget) / 100);
645 rndis_signal_connect(rndis->config);
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->config, RNDIS_MEDIUM_802_3, 0);
655 rndis_signal_disconnect(rndis->config);
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 /*
686 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
687 * configurations are bound in sequence with list_for_each_entry,
688 * in each configuration its functions are bound in sequence
689 * with list_for_each_entry, so we assume no race condition
690 * with regard to rndis_opts->bound access
691 */
692 if (!rndis_opts->bound) {
693 gether_set_gadget(rndis_opts->net, cdev->gadget);
694 status = gether_register_netdev(rndis_opts->net);
695 if (status)
696 return status;
697 rndis_opts->bound = true;
698 }
699
700 us = usb_gstrings_attach(cdev, rndis_strings,
701 ARRAY_SIZE(rndis_string_defs));
702 if (IS_ERR(us))
703 return PTR_ERR(us);
704 rndis_control_intf.iInterface = us[0].id;
705 rndis_data_intf.iInterface = us[1].id;
706 rndis_iad_descriptor.iFunction = us[2].id;
707
708 /* allocate instance-specific interface IDs */
709 status = usb_interface_id(c, f);
710 if (status < 0)
711 goto fail;
712 rndis->ctrl_id = status;
713 rndis_iad_descriptor.bFirstInterface = status;
714
715 rndis_control_intf.bInterfaceNumber = status;
716 rndis_union_desc.bMasterInterface0 = status;
717
718 status = usb_interface_id(c, f);
719 if (status < 0)
720 goto fail;
721 rndis->data_id = status;
722
723 rndis_data_intf.bInterfaceNumber = status;
724 rndis_union_desc.bSlaveInterface0 = status;
725
726 status = -ENODEV;
727
728 /* allocate instance-specific endpoints */
729 ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
730 if (!ep)
731 goto fail;
732 rndis->port.in_ep = ep;
733 ep->driver_data = cdev; /* claim */
734
735 ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
736 if (!ep)
737 goto fail;
738 rndis->port.out_ep = ep;
739 ep->driver_data = cdev; /* claim */
740
741 /* NOTE: a status/notification endpoint is, strictly speaking,
742 * optional. We don't treat it that way though! It's simpler,
743 * and some newer profiles don't treat it as optional.
744 */
745 ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
746 if (!ep)
747 goto fail;
748 rndis->notify = ep;
749 ep->driver_data = cdev; /* claim */
750
751 status = -ENOMEM;
752
753 /* allocate notification request and buffer */
754 rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
755 if (!rndis->notify_req)
756 goto fail;
757 rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
758 if (!rndis->notify_req->buf)
759 goto fail;
760 rndis->notify_req->length = STATUS_BYTECOUNT;
761 rndis->notify_req->context = rndis;
762 rndis->notify_req->complete = rndis_response_complete;
763
764 /* support all relevant hardware speeds... we expect that when
765 * hardware is dual speed, all bulk-capable endpoints work at
766 * both speeds
767 */
768 hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
769 hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
770 hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
771
772 ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
773 ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
774 ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
775
776 status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function,
777 eth_ss_function);
778 if (status)
779 goto fail;
780
781 rndis->port.open = rndis_open;
782 rndis->port.close = rndis_close;
783
784 rndis_set_param_medium(rndis->config, RNDIS_MEDIUM_802_3, 0);
785 rndis_set_host_mac(rndis->config, rndis->ethaddr);
786
787 if (rndis->manufacturer && rndis->vendorID &&
788 rndis_set_param_vendor(rndis->config, rndis->vendorID,
789 rndis->manufacturer))
790 goto fail;
791
792 /* NOTE: all that is done without knowing or caring about
793 * the network link ... which is unavailable to this code
794 * until we're activated via set_alt().
795 */
796
797 DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
798 gadget_is_superspeed(c->cdev->gadget) ? "super" :
799 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
800 rndis->port.in_ep->name, rndis->port.out_ep->name,
801 rndis->notify->name);
802 return 0;
803
804fail:
805 usb_free_all_descriptors(f);
806
807 if (rndis->notify_req) {
808 kfree(rndis->notify_req->buf);
809 usb_ep_free_request(rndis->notify, rndis->notify_req);
810 }
811
812 /* we might as well release our claims on endpoints */
813 if (rndis->notify)
814 rndis->notify->driver_data = NULL;
815 if (rndis->port.out_ep)
816 rndis->port.out_ep->driver_data = NULL;
817 if (rndis->port.in_ep)
818 rndis->port.in_ep->driver_data = NULL;
819
820 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
821
822 return status;
823}
824
825void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net)
826{
827 struct f_rndis_opts *opts;
828
829 opts = container_of(f, struct f_rndis_opts, func_inst);
830 if (opts->bound)
831 gether_cleanup(netdev_priv(opts->net));
832 else
833 free_netdev(opts->net);
834 opts->borrowed_net = opts->bound = true;
835 opts->net = net;
836}
837EXPORT_SYMBOL(rndis_borrow_net);
838
839static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item)
840{
841 return container_of(to_config_group(item), struct f_rndis_opts,
842 func_inst.group);
843}
844
845/* f_rndis_item_ops */
846USB_ETHERNET_CONFIGFS_ITEM(rndis);
847
848/* f_rndis_opts_dev_addr */
849USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis);
850
851/* f_rndis_opts_host_addr */
852USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis);
853
854/* f_rndis_opts_qmult */
855USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis);
856
857/* f_rndis_opts_ifname */
858USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis);
859
860static struct configfs_attribute *rndis_attrs[] = {
861 &f_rndis_opts_dev_addr.attr,
862 &f_rndis_opts_host_addr.attr,
863 &f_rndis_opts_qmult.attr,
864 &f_rndis_opts_ifname.attr,
865 NULL,
866};
867
868static struct config_item_type rndis_func_type = {
869 .ct_item_ops = &rndis_item_ops,
870 .ct_attrs = rndis_attrs,
871 .ct_owner = THIS_MODULE,
872};
873
874static void rndis_free_inst(struct usb_function_instance *f)
875{
876 struct f_rndis_opts *opts;
877
878 opts = container_of(f, struct f_rndis_opts, func_inst);
879 if (!opts->borrowed_net) {
880 if (opts->bound)
881 gether_cleanup(netdev_priv(opts->net));
882 else
883 free_netdev(opts->net);
884 }
885 kfree(opts);
886}
887
888static struct usb_function_instance *rndis_alloc_inst(void)
889{
890 struct f_rndis_opts *opts;
891
892 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
893 if (!opts)
894 return ERR_PTR(-ENOMEM);
895 mutex_init(&opts->lock);
896 opts->func_inst.free_func_inst = rndis_free_inst;
897 opts->net = gether_setup_default();
898 if (IS_ERR(opts->net)) {
899 struct net_device *net = opts->net;
900 kfree(opts);
901 return ERR_CAST(net);
902 }
903
904 config_group_init_type_name(&opts->func_inst.group, "",
905 &rndis_func_type);
906
907 return &opts->func_inst;
908}
909
910static void rndis_free(struct usb_function *f)
911{
912 struct f_rndis *rndis;
913 struct f_rndis_opts *opts;
914
915 rndis = func_to_rndis(f);
916 rndis_deregister(rndis->config);
917 opts = container_of(f->fi, struct f_rndis_opts, func_inst);
918 kfree(rndis);
919 mutex_lock(&opts->lock);
920 opts->refcnt--;
921 mutex_unlock(&opts->lock);
922}
923
924static void rndis_unbind(struct usb_configuration *c, struct usb_function *f)
925{
926 struct f_rndis *rndis = func_to_rndis(f);
927
928 usb_free_all_descriptors(f);
929
930 kfree(rndis->notify_req->buf);
931 usb_ep_free_request(rndis->notify, rndis->notify_req);
932}
933
934static struct usb_function *rndis_alloc(struct usb_function_instance *fi)
935{
936 struct f_rndis *rndis;
937 struct f_rndis_opts *opts;
938 int status;
939
940 /* allocate and initialize one new instance */
941 rndis = kzalloc(sizeof(*rndis), GFP_KERNEL);
942 if (!rndis)
943 return ERR_PTR(-ENOMEM);
944
945 opts = container_of(fi, struct f_rndis_opts, func_inst);
946 mutex_lock(&opts->lock);
947 opts->refcnt++;
948
949 gether_get_host_addr_u8(opts->net, rndis->ethaddr);
950 rndis->vendorID = opts->vendor_id;
951 rndis->manufacturer = opts->manufacturer;
952
953 rndis->port.ioport = netdev_priv(opts->net);
954 mutex_unlock(&opts->lock);
955 /* RNDIS activates when the host changes this filter */
956 rndis->port.cdc_filter = 0;
957
958 /* RNDIS has special (and complex) framing */
959 rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
960 rndis->port.wrap = rndis_add_header;
961 rndis->port.unwrap = rndis_rm_hdr;
962
963 rndis->port.func.name = "rndis";
964 /* descriptors are per-instance copies */
965 rndis->port.func.bind = rndis_bind;
966 rndis->port.func.unbind = rndis_unbind;
967 rndis->port.func.set_alt = rndis_set_alt;
968 rndis->port.func.setup = rndis_setup;
969 rndis->port.func.disable = rndis_disable;
970 rndis->port.func.free_func = rndis_free;
971
972 status = rndis_register(rndis_response_available, rndis);
973 if (status < 0) {
974 kfree(rndis);
975 return ERR_PTR(status);
976 }
977 rndis->config = status;
978
979 return &rndis->port.func;
980}
981
982DECLARE_USB_FUNCTION(rndis, rndis_alloc_inst, rndis_alloc);
983
984static int __init rndis_mod_init(void)
985{
986 int ret;
987
988 ret = rndis_init();
989 if (ret)
990 return ret;
991
992 return usb_function_register(&rndisusb_func);
993}
994module_init(rndis_mod_init);
995
996static void __exit rndis_mod_exit(void)
997{
998 usb_function_unregister(&rndisusb_func);
999 rndis_exit();
1000}
1001module_exit(rndis_mod_exit);
1002
1003MODULE_LICENSE("GPL");
1004MODULE_AUTHOR("David Brownell");