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v4.6
 
   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");
v6.2
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * f_rndis.c -- RNDIS link function driver
   4 *
   5 * Copyright (C) 2003-2005,2008 David Brownell
   6 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
   7 * Copyright (C) 2008 Nokia Corporation
   8 * Copyright (C) 2009 Samsung Electronics
   9 *                    Author: Michal Nazarewicz (mina86@mina86.com)
 
 
 
 
 
  10 */
  11
  12/* #define VERBOSE_DEBUG */
  13
  14#include <linux/slab.h>
  15#include <linux/kernel.h>
  16#include <linux/module.h>
  17#include <linux/device.h>
  18#include <linux/etherdevice.h>
  19
  20#include <linux/atomic.h>
  21
  22#include "u_ether.h"
  23#include "u_ether_configfs.h"
  24#include "u_rndis.h"
  25#include "rndis.h"
  26#include "configfs.h"
  27
  28/*
  29 * This function is an RNDIS Ethernet port -- a Microsoft protocol that's
  30 * been promoted instead of the standard CDC Ethernet.  The published RNDIS
  31 * spec is ambiguous, incomplete, and needlessly complex.  Variants such as
  32 * ActiveSync have even worse status in terms of specification.
  33 *
  34 * In short:  it's a protocol controlled by (and for) Microsoft, not for an
  35 * Open ecosystem or markets.  Linux supports it *only* because Microsoft
  36 * doesn't support the CDC Ethernet standard.
  37 *
  38 * The RNDIS data transfer model is complex, with multiple Ethernet packets
  39 * per USB message, and out of band data.  The control model is built around
  40 * what's essentially an "RNDIS RPC" protocol.  It's all wrapped in a CDC ACM
  41 * (modem, not Ethernet) veneer, with those ACM descriptors being entirely
  42 * useless (they're ignored).  RNDIS expects to be the only function in its
  43 * configuration, so it's no real help if you need composite devices; and
  44 * it expects to be the first configuration too.
  45 *
  46 * There is a single technical advantage of RNDIS over CDC Ethernet, if you
  47 * discount the fluff that its RPC can be made to deliver: it doesn't need
  48 * a NOP altsetting for the data interface.  That lets it work on some of the
  49 * "so smart it's stupid" hardware which takes over configuration changes
  50 * from the software, and adds restrictions like "no altsettings".
  51 *
  52 * Unfortunately MSFT's RNDIS drivers are buggy.  They hang or oops, and
  53 * have all sorts of contrary-to-specification oddities that can prevent
  54 * them from working sanely.  Since bugfixes (or accurate specs, letting
  55 * Linux work around those bugs) are unlikely to ever come from MSFT, you
  56 * may want to avoid using RNDIS on purely operational grounds.
  57 *
  58 * Omissions from the RNDIS 1.0 specification include:
  59 *
  60 *   - Power management ... references data that's scattered around lots
  61 *     of other documentation, which is incorrect/incomplete there too.
  62 *
  63 *   - There are various undocumented protocol requirements, like the need
  64 *     to send garbage in some control-OUT messages.
  65 *
  66 *   - MS-Windows drivers sometimes emit undocumented requests.
  67 */
  68
  69struct f_rndis {
  70	struct gether			port;
  71	u8				ctrl_id, data_id;
  72	u8				ethaddr[ETH_ALEN];
  73	u32				vendorID;
  74	const char			*manufacturer;
  75	struct rndis_params		*params;
  76
  77	struct usb_ep			*notify;
  78	struct usb_request		*notify_req;
  79	atomic_t			notify_count;
  80};
  81
  82static inline struct f_rndis *func_to_rndis(struct usb_function *f)
  83{
  84	return container_of(f, struct f_rndis, port.func);
  85}
  86
  87/* peak (theoretical) bulk transfer rate in bits-per-second */
  88static unsigned int bitrate(struct usb_gadget *g)
  89{
  90	if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
  91		return 4250000000U;
  92	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
  93		return 3750000000U;
  94	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
  95		return 13 * 512 * 8 * 1000 * 8;
  96	else
  97		return 19 * 64 * 1 * 1000 * 8;
  98}
  99
 100/*-------------------------------------------------------------------------*/
 101
 102/*
 103 */
 104
 105#define RNDIS_STATUS_INTERVAL_MS	32
 106#define STATUS_BYTECOUNT		8	/* 8 bytes data */
 107
 108
 109/* interface descriptor: */
 110
 111static struct usb_interface_descriptor rndis_control_intf = {
 112	.bLength =		sizeof rndis_control_intf,
 113	.bDescriptorType =	USB_DT_INTERFACE,
 114
 115	/* .bInterfaceNumber = DYNAMIC */
 116	/* status endpoint is optional; this could be patched later */
 117	.bNumEndpoints =	1,
 118	.bInterfaceClass =	USB_CLASS_COMM,
 119	.bInterfaceSubClass =   USB_CDC_SUBCLASS_ACM,
 120	.bInterfaceProtocol =   USB_CDC_ACM_PROTO_VENDOR,
 121	/* .iInterface = DYNAMIC */
 122};
 123
 124static struct usb_cdc_header_desc header_desc = {
 125	.bLength =		sizeof header_desc,
 126	.bDescriptorType =	USB_DT_CS_INTERFACE,
 127	.bDescriptorSubType =	USB_CDC_HEADER_TYPE,
 128
 129	.bcdCDC =		cpu_to_le16(0x0110),
 130};
 131
 132static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = {
 133	.bLength =		sizeof call_mgmt_descriptor,
 134	.bDescriptorType =	USB_DT_CS_INTERFACE,
 135	.bDescriptorSubType =	USB_CDC_CALL_MANAGEMENT_TYPE,
 136
 137	.bmCapabilities =	0x00,
 138	.bDataInterface =	0x01,
 139};
 140
 141static struct usb_cdc_acm_descriptor rndis_acm_descriptor = {
 142	.bLength =		sizeof rndis_acm_descriptor,
 143	.bDescriptorType =	USB_DT_CS_INTERFACE,
 144	.bDescriptorSubType =	USB_CDC_ACM_TYPE,
 145
 146	.bmCapabilities =	0x00,
 147};
 148
 149static struct usb_cdc_union_desc rndis_union_desc = {
 150	.bLength =		sizeof(rndis_union_desc),
 151	.bDescriptorType =	USB_DT_CS_INTERFACE,
 152	.bDescriptorSubType =	USB_CDC_UNION_TYPE,
 153	/* .bMasterInterface0 =	DYNAMIC */
 154	/* .bSlaveInterface0 =	DYNAMIC */
 155};
 156
 157/* the data interface has two bulk endpoints */
 158
 159static struct usb_interface_descriptor rndis_data_intf = {
 160	.bLength =		sizeof rndis_data_intf,
 161	.bDescriptorType =	USB_DT_INTERFACE,
 162
 163	/* .bInterfaceNumber = DYNAMIC */
 164	.bNumEndpoints =	2,
 165	.bInterfaceClass =	USB_CLASS_CDC_DATA,
 166	.bInterfaceSubClass =	0,
 167	.bInterfaceProtocol =	0,
 168	/* .iInterface = DYNAMIC */
 169};
 170
 171
 172static struct usb_interface_assoc_descriptor
 173rndis_iad_descriptor = {
 174	.bLength =		sizeof rndis_iad_descriptor,
 175	.bDescriptorType =	USB_DT_INTERFACE_ASSOCIATION,
 176
 177	.bFirstInterface =	0, /* XXX, hardcoded */
 178	.bInterfaceCount = 	2,	// control + data
 179	.bFunctionClass =	USB_CLASS_COMM,
 180	.bFunctionSubClass =	USB_CDC_SUBCLASS_ETHERNET,
 181	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
 182	/* .iFunction = DYNAMIC */
 183};
 184
 185/* full speed support: */
 186
 187static struct usb_endpoint_descriptor fs_notify_desc = {
 188	.bLength =		USB_DT_ENDPOINT_SIZE,
 189	.bDescriptorType =	USB_DT_ENDPOINT,
 190
 191	.bEndpointAddress =	USB_DIR_IN,
 192	.bmAttributes =		USB_ENDPOINT_XFER_INT,
 193	.wMaxPacketSize =	cpu_to_le16(STATUS_BYTECOUNT),
 194	.bInterval =		RNDIS_STATUS_INTERVAL_MS,
 195};
 196
 197static struct usb_endpoint_descriptor fs_in_desc = {
 198	.bLength =		USB_DT_ENDPOINT_SIZE,
 199	.bDescriptorType =	USB_DT_ENDPOINT,
 200
 201	.bEndpointAddress =	USB_DIR_IN,
 202	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 203};
 204
 205static struct usb_endpoint_descriptor fs_out_desc = {
 206	.bLength =		USB_DT_ENDPOINT_SIZE,
 207	.bDescriptorType =	USB_DT_ENDPOINT,
 208
 209	.bEndpointAddress =	USB_DIR_OUT,
 210	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 211};
 212
 213static struct usb_descriptor_header *eth_fs_function[] = {
 214	(struct usb_descriptor_header *) &rndis_iad_descriptor,
 215
 216	/* control interface matches ACM, not Ethernet */
 217	(struct usb_descriptor_header *) &rndis_control_intf,
 218	(struct usb_descriptor_header *) &header_desc,
 219	(struct usb_descriptor_header *) &call_mgmt_descriptor,
 220	(struct usb_descriptor_header *) &rndis_acm_descriptor,
 221	(struct usb_descriptor_header *) &rndis_union_desc,
 222	(struct usb_descriptor_header *) &fs_notify_desc,
 223
 224	/* data interface has no altsetting */
 225	(struct usb_descriptor_header *) &rndis_data_intf,
 226	(struct usb_descriptor_header *) &fs_in_desc,
 227	(struct usb_descriptor_header *) &fs_out_desc,
 228	NULL,
 229};
 230
 231/* high speed support: */
 232
 233static struct usb_endpoint_descriptor hs_notify_desc = {
 234	.bLength =		USB_DT_ENDPOINT_SIZE,
 235	.bDescriptorType =	USB_DT_ENDPOINT,
 236
 237	.bEndpointAddress =	USB_DIR_IN,
 238	.bmAttributes =		USB_ENDPOINT_XFER_INT,
 239	.wMaxPacketSize =	cpu_to_le16(STATUS_BYTECOUNT),
 240	.bInterval =		USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
 241};
 242
 243static struct usb_endpoint_descriptor hs_in_desc = {
 244	.bLength =		USB_DT_ENDPOINT_SIZE,
 245	.bDescriptorType =	USB_DT_ENDPOINT,
 246
 247	.bEndpointAddress =	USB_DIR_IN,
 248	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 249	.wMaxPacketSize =	cpu_to_le16(512),
 250};
 251
 252static struct usb_endpoint_descriptor hs_out_desc = {
 253	.bLength =		USB_DT_ENDPOINT_SIZE,
 254	.bDescriptorType =	USB_DT_ENDPOINT,
 255
 256	.bEndpointAddress =	USB_DIR_OUT,
 257	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 258	.wMaxPacketSize =	cpu_to_le16(512),
 259};
 260
 261static struct usb_descriptor_header *eth_hs_function[] = {
 262	(struct usb_descriptor_header *) &rndis_iad_descriptor,
 263
 264	/* control interface matches ACM, not Ethernet */
 265	(struct usb_descriptor_header *) &rndis_control_intf,
 266	(struct usb_descriptor_header *) &header_desc,
 267	(struct usb_descriptor_header *) &call_mgmt_descriptor,
 268	(struct usb_descriptor_header *) &rndis_acm_descriptor,
 269	(struct usb_descriptor_header *) &rndis_union_desc,
 270	(struct usb_descriptor_header *) &hs_notify_desc,
 271
 272	/* data interface has no altsetting */
 273	(struct usb_descriptor_header *) &rndis_data_intf,
 274	(struct usb_descriptor_header *) &hs_in_desc,
 275	(struct usb_descriptor_header *) &hs_out_desc,
 276	NULL,
 277};
 278
 279/* super speed support: */
 280
 281static struct usb_endpoint_descriptor ss_notify_desc = {
 282	.bLength =		USB_DT_ENDPOINT_SIZE,
 283	.bDescriptorType =	USB_DT_ENDPOINT,
 284
 285	.bEndpointAddress =	USB_DIR_IN,
 286	.bmAttributes =		USB_ENDPOINT_XFER_INT,
 287	.wMaxPacketSize =	cpu_to_le16(STATUS_BYTECOUNT),
 288	.bInterval =		USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS)
 289};
 290
 291static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = {
 292	.bLength =		sizeof ss_intr_comp_desc,
 293	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
 294
 295	/* the following 3 values can be tweaked if necessary */
 296	/* .bMaxBurst =		0, */
 297	/* .bmAttributes =	0, */
 298	.wBytesPerInterval =	cpu_to_le16(STATUS_BYTECOUNT),
 299};
 300
 301static struct usb_endpoint_descriptor ss_in_desc = {
 302	.bLength =		USB_DT_ENDPOINT_SIZE,
 303	.bDescriptorType =	USB_DT_ENDPOINT,
 304
 305	.bEndpointAddress =	USB_DIR_IN,
 306	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 307	.wMaxPacketSize =	cpu_to_le16(1024),
 308};
 309
 310static struct usb_endpoint_descriptor ss_out_desc = {
 311	.bLength =		USB_DT_ENDPOINT_SIZE,
 312	.bDescriptorType =	USB_DT_ENDPOINT,
 313
 314	.bEndpointAddress =	USB_DIR_OUT,
 315	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
 316	.wMaxPacketSize =	cpu_to_le16(1024),
 317};
 318
 319static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = {
 320	.bLength =		sizeof ss_bulk_comp_desc,
 321	.bDescriptorType =	USB_DT_SS_ENDPOINT_COMP,
 322
 323	/* the following 2 values can be tweaked if necessary */
 324	/* .bMaxBurst =		0, */
 325	/* .bmAttributes =	0, */
 326};
 327
 328static struct usb_descriptor_header *eth_ss_function[] = {
 329	(struct usb_descriptor_header *) &rndis_iad_descriptor,
 330
 331	/* control interface matches ACM, not Ethernet */
 332	(struct usb_descriptor_header *) &rndis_control_intf,
 333	(struct usb_descriptor_header *) &header_desc,
 334	(struct usb_descriptor_header *) &call_mgmt_descriptor,
 335	(struct usb_descriptor_header *) &rndis_acm_descriptor,
 336	(struct usb_descriptor_header *) &rndis_union_desc,
 337	(struct usb_descriptor_header *) &ss_notify_desc,
 338	(struct usb_descriptor_header *) &ss_intr_comp_desc,
 339
 340	/* data interface has no altsetting */
 341	(struct usb_descriptor_header *) &rndis_data_intf,
 342	(struct usb_descriptor_header *) &ss_in_desc,
 343	(struct usb_descriptor_header *) &ss_bulk_comp_desc,
 344	(struct usb_descriptor_header *) &ss_out_desc,
 345	(struct usb_descriptor_header *) &ss_bulk_comp_desc,
 346	NULL,
 347};
 348
 349/* string descriptors: */
 350
 351static struct usb_string rndis_string_defs[] = {
 352	[0].s = "RNDIS Communications Control",
 353	[1].s = "RNDIS Ethernet Data",
 354	[2].s = "RNDIS",
 355	{  } /* end of list */
 356};
 357
 358static struct usb_gadget_strings rndis_string_table = {
 359	.language =		0x0409,	/* en-us */
 360	.strings =		rndis_string_defs,
 361};
 362
 363static struct usb_gadget_strings *rndis_strings[] = {
 364	&rndis_string_table,
 365	NULL,
 366};
 367
 368/*-------------------------------------------------------------------------*/
 369
 370static struct sk_buff *rndis_add_header(struct gether *port,
 371					struct sk_buff *skb)
 372{
 373	struct sk_buff *skb2;
 374
 375	if (!skb)
 376		return NULL;
 377
 378	skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
 379	rndis_add_hdr(skb2);
 380
 381	dev_kfree_skb(skb);
 382	return skb2;
 383}
 384
 385static void rndis_response_available(void *_rndis)
 386{
 387	struct f_rndis			*rndis = _rndis;
 388	struct usb_request		*req = rndis->notify_req;
 389	struct usb_composite_dev	*cdev = rndis->port.func.config->cdev;
 390	__le32				*data = req->buf;
 391	int				status;
 392
 393	if (atomic_inc_return(&rndis->notify_count) != 1)
 394		return;
 395
 396	/* Send RNDIS RESPONSE_AVAILABLE notification; a
 397	 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too
 398	 *
 399	 * This is the only notification defined by RNDIS.
 400	 */
 401	data[0] = cpu_to_le32(1);
 402	data[1] = cpu_to_le32(0);
 403
 404	status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
 405	if (status) {
 406		atomic_dec(&rndis->notify_count);
 407		DBG(cdev, "notify/0 --> %d\n", status);
 408	}
 409}
 410
 411static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
 412{
 413	struct f_rndis			*rndis = req->context;
 414	struct usb_composite_dev	*cdev = rndis->port.func.config->cdev;
 415	int				status = req->status;
 416
 417	/* after TX:
 418	 *  - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control)
 419	 *  - RNDIS_RESPONSE_AVAILABLE (status/irq)
 420	 */
 421	switch (status) {
 422	case -ECONNRESET:
 423	case -ESHUTDOWN:
 424		/* connection gone */
 425		atomic_set(&rndis->notify_count, 0);
 426		break;
 427	default:
 428		DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
 429			ep->name, status,
 430			req->actual, req->length);
 431		fallthrough;
 432	case 0:
 433		if (ep != rndis->notify)
 434			break;
 435
 436		/* handle multiple pending RNDIS_RESPONSE_AVAILABLE
 437		 * notifications by resending until we're done
 438		 */
 439		if (atomic_dec_and_test(&rndis->notify_count))
 440			break;
 441		status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
 442		if (status) {
 443			atomic_dec(&rndis->notify_count);
 444			DBG(cdev, "notify/1 --> %d\n", status);
 445		}
 446		break;
 447	}
 448}
 449
 450static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req)
 451{
 452	struct f_rndis			*rndis = req->context;
 453	int				status;
 454
 455	/* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */
 456//	spin_lock(&dev->lock);
 457	status = rndis_msg_parser(rndis->params, (u8 *) req->buf);
 458	if (status < 0)
 459		pr_err("RNDIS command error %d, %d/%d\n",
 460			status, req->actual, req->length);
 461//	spin_unlock(&dev->lock);
 462}
 463
 464static int
 465rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 466{
 467	struct f_rndis		*rndis = func_to_rndis(f);
 468	struct usb_composite_dev *cdev = f->config->cdev;
 469	struct usb_request	*req = cdev->req;
 470	int			value = -EOPNOTSUPP;
 471	u16			w_index = le16_to_cpu(ctrl->wIndex);
 472	u16			w_value = le16_to_cpu(ctrl->wValue);
 473	u16			w_length = le16_to_cpu(ctrl->wLength);
 474
 475	/* composite driver infrastructure handles everything except
 476	 * CDC class messages; interface activation uses set_alt().
 477	 */
 478	switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 479
 480	/* RNDIS uses the CDC command encapsulation mechanism to implement
 481	 * an RPC scheme, with much getting/setting of attributes by OID.
 482	 */
 483	case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 484			| USB_CDC_SEND_ENCAPSULATED_COMMAND:
 485		if (w_value || w_index != rndis->ctrl_id)
 486			goto invalid;
 487		/* read the request; process it later */
 488		value = w_length;
 489		req->complete = rndis_command_complete;
 490		req->context = rndis;
 491		/* later, rndis_response_available() sends a notification */
 492		break;
 493
 494	case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 495			| USB_CDC_GET_ENCAPSULATED_RESPONSE:
 496		if (w_value || w_index != rndis->ctrl_id)
 497			goto invalid;
 498		else {
 499			u8 *buf;
 500			u32 n;
 501
 502			/* return the result */
 503			buf = rndis_get_next_response(rndis->params, &n);
 504			if (buf) {
 505				memcpy(req->buf, buf, n);
 506				req->complete = rndis_response_complete;
 507				req->context = rndis;
 508				rndis_free_response(rndis->params, buf);
 509				value = n;
 510			}
 511			/* else stalls ... spec says to avoid that */
 512		}
 513		break;
 514
 515	default:
 516invalid:
 517		VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 518			ctrl->bRequestType, ctrl->bRequest,
 519			w_value, w_index, w_length);
 520	}
 521
 522	/* respond with data transfer or status phase? */
 523	if (value >= 0) {
 524		DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n",
 525			ctrl->bRequestType, ctrl->bRequest,
 526			w_value, w_index, w_length);
 527		req->zero = (value < w_length);
 528		req->length = value;
 529		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 530		if (value < 0)
 531			ERROR(cdev, "rndis response on err %d\n", value);
 532	}
 533
 534	/* device either stalls (value < 0) or reports success */
 535	return value;
 536}
 537
 538
 539static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 540{
 541	struct f_rndis		*rndis = func_to_rndis(f);
 542	struct usb_composite_dev *cdev = f->config->cdev;
 543
 544	/* we know alt == 0 */
 545
 546	if (intf == rndis->ctrl_id) {
 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
 557	} else if (intf == rndis->data_id) {
 558		struct net_device	*net;
 559
 560		if (rndis->port.in_ep->enabled) {
 561			DBG(cdev, "reset rndis\n");
 562			gether_disconnect(&rndis->port);
 563		}
 564
 565		if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) {
 566			DBG(cdev, "init rndis\n");
 567			if (config_ep_by_speed(cdev->gadget, f,
 568					       rndis->port.in_ep) ||
 569			    config_ep_by_speed(cdev->gadget, f,
 570					       rndis->port.out_ep)) {
 571				rndis->port.in_ep->desc = NULL;
 572				rndis->port.out_ep->desc = NULL;
 573				goto fail;
 574			}
 575		}
 576
 577		/* Avoid ZLPs; they can be troublesome. */
 578		rndis->port.is_zlp_ok = false;
 579
 580		/* RNDIS should be in the "RNDIS uninitialized" state,
 581		 * either never activated or after rndis_uninit().
 582		 *
 583		 * We don't want data to flow here until a nonzero packet
 584		 * filter is set, at which point it enters "RNDIS data
 585		 * initialized" state ... but we do want the endpoints
 586		 * to be activated.  It's a strange little state.
 587		 *
 588		 * REVISIT the RNDIS gadget code has done this wrong for a
 589		 * very long time.  We need another call to the link layer
 590		 * code -- gether_updown(...bool) maybe -- to do it right.
 591		 */
 592		rndis->port.cdc_filter = 0;
 593
 594		DBG(cdev, "RNDIS RX/TX early activation ... \n");
 595		net = gether_connect(&rndis->port);
 596		if (IS_ERR(net))
 597			return PTR_ERR(net);
 598
 599		rndis_set_param_dev(rndis->params, net,
 600				&rndis->port.cdc_filter);
 601	} else
 602		goto fail;
 603
 604	return 0;
 605fail:
 606	return -EINVAL;
 607}
 608
 609static void rndis_disable(struct usb_function *f)
 610{
 611	struct f_rndis		*rndis = func_to_rndis(f);
 612	struct usb_composite_dev *cdev = f->config->cdev;
 613
 614	if (!rndis->notify->enabled)
 615		return;
 616
 617	DBG(cdev, "rndis deactivated\n");
 618
 619	rndis_uninit(rndis->params);
 620	gether_disconnect(&rndis->port);
 621
 622	usb_ep_disable(rndis->notify);
 623	rndis->notify->desc = NULL;
 624}
 625
 626/*-------------------------------------------------------------------------*/
 627
 628/*
 629 * This isn't quite the same mechanism as CDC Ethernet, since the
 630 * notification scheme passes less data, but the same set of link
 631 * states must be tested.  A key difference is that altsettings are
 632 * not used to tell whether the link should send packets or not.
 633 */
 634
 635static void rndis_open(struct gether *geth)
 636{
 637	struct f_rndis		*rndis = func_to_rndis(&geth->func);
 638	struct usb_composite_dev *cdev = geth->func.config->cdev;
 639
 640	DBG(cdev, "%s\n", __func__);
 641
 642	rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3,
 643				bitrate(cdev->gadget) / 100);
 644	rndis_signal_connect(rndis->params);
 645}
 646
 647static void rndis_close(struct gether *geth)
 648{
 649	struct f_rndis		*rndis = func_to_rndis(&geth->func);
 650
 651	DBG(geth->func.config->cdev, "%s\n", __func__);
 652
 653	rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
 654	rndis_signal_disconnect(rndis->params);
 655}
 656
 657/*-------------------------------------------------------------------------*/
 658
 659/* Some controllers can't support RNDIS ... */
 660static inline bool can_support_rndis(struct usb_configuration *c)
 661{
 662	/* everything else is *presumably* fine */
 663	return true;
 664}
 665
 666/* ethernet function driver setup/binding */
 667
 668static int
 669rndis_bind(struct usb_configuration *c, struct usb_function *f)
 670{
 671	struct usb_composite_dev *cdev = c->cdev;
 672	struct f_rndis		*rndis = func_to_rndis(f);
 673	struct usb_string	*us;
 674	int			status;
 675	struct usb_ep		*ep;
 676
 677	struct f_rndis_opts *rndis_opts;
 678
 679	if (!can_support_rndis(c))
 680		return -EINVAL;
 681
 682	rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst);
 683
 684	if (cdev->use_os_string) {
 685		f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
 686					   GFP_KERNEL);
 687		if (!f->os_desc_table)
 688			return -ENOMEM;
 689		f->os_desc_n = 1;
 690		f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc;
 691	}
 692
 693	rndis_iad_descriptor.bFunctionClass = rndis_opts->class;
 694	rndis_iad_descriptor.bFunctionSubClass = rndis_opts->subclass;
 695	rndis_iad_descriptor.bFunctionProtocol = rndis_opts->protocol;
 696
 697	/*
 698	 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
 699	 * configurations are bound in sequence with list_for_each_entry,
 700	 * in each configuration its functions are bound in sequence
 701	 * with list_for_each_entry, so we assume no race condition
 702	 * with regard to rndis_opts->bound access
 703	 */
 704	if (!rndis_opts->bound) {
 705		gether_set_gadget(rndis_opts->net, cdev->gadget);
 706		status = gether_register_netdev(rndis_opts->net);
 707		if (status)
 708			goto fail;
 709		rndis_opts->bound = true;
 710	}
 711
 712	us = usb_gstrings_attach(cdev, rndis_strings,
 713				 ARRAY_SIZE(rndis_string_defs));
 714	if (IS_ERR(us)) {
 715		status = PTR_ERR(us);
 716		goto fail;
 717	}
 718	rndis_control_intf.iInterface = us[0].id;
 719	rndis_data_intf.iInterface = us[1].id;
 720	rndis_iad_descriptor.iFunction = us[2].id;
 721
 722	/* allocate instance-specific interface IDs */
 723	status = usb_interface_id(c, f);
 724	if (status < 0)
 725		goto fail;
 726	rndis->ctrl_id = status;
 727	rndis_iad_descriptor.bFirstInterface = status;
 728
 729	rndis_control_intf.bInterfaceNumber = status;
 730	rndis_union_desc.bMasterInterface0 = status;
 731
 732	if (cdev->use_os_string)
 733		f->os_desc_table[0].if_id =
 734			rndis_iad_descriptor.bFirstInterface;
 735
 736	status = usb_interface_id(c, f);
 737	if (status < 0)
 738		goto fail;
 739	rndis->data_id = status;
 740
 741	rndis_data_intf.bInterfaceNumber = status;
 742	rndis_union_desc.bSlaveInterface0 = status;
 743
 744	status = -ENODEV;
 745
 746	/* allocate instance-specific endpoints */
 747	ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
 748	if (!ep)
 749		goto fail;
 750	rndis->port.in_ep = ep;
 751
 752	ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
 753	if (!ep)
 754		goto fail;
 755	rndis->port.out_ep = ep;
 756
 757	/* NOTE:  a status/notification endpoint is, strictly speaking,
 758	 * optional.  We don't treat it that way though!  It's simpler,
 759	 * and some newer profiles don't treat it as optional.
 760	 */
 761	ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
 762	if (!ep)
 763		goto fail;
 764	rndis->notify = ep;
 765
 766	status = -ENOMEM;
 767
 768	/* allocate notification request and buffer */
 769	rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
 770	if (!rndis->notify_req)
 771		goto fail;
 772	rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
 773	if (!rndis->notify_req->buf)
 774		goto fail;
 775	rndis->notify_req->length = STATUS_BYTECOUNT;
 776	rndis->notify_req->context = rndis;
 777	rndis->notify_req->complete = rndis_response_complete;
 778
 779	/* support all relevant hardware speeds... we expect that when
 780	 * hardware is dual speed, all bulk-capable endpoints work at
 781	 * both speeds
 782	 */
 783	hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
 784	hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
 785	hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
 786
 787	ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress;
 788	ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress;
 789	ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress;
 790
 791	status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function,
 792			eth_ss_function, eth_ss_function);
 793	if (status)
 794		goto fail;
 795
 796	rndis->port.open = rndis_open;
 797	rndis->port.close = rndis_close;
 798
 799	rndis_set_param_medium(rndis->params, RNDIS_MEDIUM_802_3, 0);
 800	rndis_set_host_mac(rndis->params, rndis->ethaddr);
 801
 802	if (rndis->manufacturer && rndis->vendorID &&
 803			rndis_set_param_vendor(rndis->params, rndis->vendorID,
 804					       rndis->manufacturer)) {
 805		status = -EINVAL;
 806		goto fail_free_descs;
 807	}
 808
 809	/* NOTE:  all that is done without knowing or caring about
 810	 * the network link ... which is unavailable to this code
 811	 * until we're activated via set_alt().
 812	 */
 813
 814	DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
 815			gadget_is_superspeed(c->cdev->gadget) ? "super" :
 816			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
 817			rndis->port.in_ep->name, rndis->port.out_ep->name,
 818			rndis->notify->name);
 819	return 0;
 820
 821fail_free_descs:
 822	usb_free_all_descriptors(f);
 823fail:
 824	kfree(f->os_desc_table);
 825	f->os_desc_n = 0;
 826
 827	if (rndis->notify_req) {
 828		kfree(rndis->notify_req->buf);
 829		usb_ep_free_request(rndis->notify, rndis->notify_req);
 830	}
 831
 832	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
 833
 834	return status;
 835}
 836
 837void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net)
 838{
 839	struct f_rndis_opts *opts;
 840
 841	opts = container_of(f, struct f_rndis_opts, func_inst);
 842	if (opts->bound)
 843		gether_cleanup(netdev_priv(opts->net));
 844	else
 845		free_netdev(opts->net);
 846	opts->borrowed_net = opts->bound = true;
 847	opts->net = net;
 848}
 849EXPORT_SYMBOL_GPL(rndis_borrow_net);
 850
 851static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item)
 852{
 853	return container_of(to_config_group(item), struct f_rndis_opts,
 854			    func_inst.group);
 855}
 856
 857/* f_rndis_item_ops */
 858USB_ETHERNET_CONFIGFS_ITEM(rndis);
 859
 860/* f_rndis_opts_dev_addr */
 861USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis);
 862
 863/* f_rndis_opts_host_addr */
 864USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis);
 865
 866/* f_rndis_opts_qmult */
 867USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis);
 868
 869/* f_rndis_opts_ifname */
 870USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis);
 871
 872/* f_rndis_opts_class */
 873USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, class);
 874
 875/* f_rndis_opts_subclass */
 876USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, subclass);
 877
 878/* f_rndis_opts_protocol */
 879USB_ETHER_CONFIGFS_ITEM_ATTR_U8_RW(rndis, protocol);
 880
 881static struct configfs_attribute *rndis_attrs[] = {
 882	&rndis_opts_attr_dev_addr,
 883	&rndis_opts_attr_host_addr,
 884	&rndis_opts_attr_qmult,
 885	&rndis_opts_attr_ifname,
 886	&rndis_opts_attr_class,
 887	&rndis_opts_attr_subclass,
 888	&rndis_opts_attr_protocol,
 889	NULL,
 890};
 891
 892static const struct config_item_type rndis_func_type = {
 893	.ct_item_ops	= &rndis_item_ops,
 894	.ct_attrs	= rndis_attrs,
 895	.ct_owner	= THIS_MODULE,
 896};
 897
 898static void rndis_free_inst(struct usb_function_instance *f)
 899{
 900	struct f_rndis_opts *opts;
 901
 902	opts = container_of(f, struct f_rndis_opts, func_inst);
 903	if (!opts->borrowed_net) {
 904		if (opts->bound)
 905			gether_cleanup(netdev_priv(opts->net));
 906		else
 907			free_netdev(opts->net);
 908	}
 909
 910	kfree(opts->rndis_interf_group);	/* single VLA chunk */
 911	kfree(opts);
 912}
 913
 914static struct usb_function_instance *rndis_alloc_inst(void)
 915{
 916	struct f_rndis_opts *opts;
 917	struct usb_os_desc *descs[1];
 918	char *names[1];
 919	struct config_group *rndis_interf_group;
 920
 921	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 922	if (!opts)
 923		return ERR_PTR(-ENOMEM);
 924	opts->rndis_os_desc.ext_compat_id = opts->rndis_ext_compat_id;
 925
 926	mutex_init(&opts->lock);
 927	opts->func_inst.free_func_inst = rndis_free_inst;
 928	opts->net = gether_setup_default();
 929	if (IS_ERR(opts->net)) {
 930		struct net_device *net = opts->net;
 931		kfree(opts);
 932		return ERR_CAST(net);
 933	}
 934	INIT_LIST_HEAD(&opts->rndis_os_desc.ext_prop);
 935
 936	opts->class = rndis_iad_descriptor.bFunctionClass;
 937	opts->subclass = rndis_iad_descriptor.bFunctionSubClass;
 938	opts->protocol = rndis_iad_descriptor.bFunctionProtocol;
 939
 940	descs[0] = &opts->rndis_os_desc;
 941	names[0] = "rndis";
 942	config_group_init_type_name(&opts->func_inst.group, "",
 943				    &rndis_func_type);
 944	rndis_interf_group =
 945		usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
 946					       names, THIS_MODULE);
 947	if (IS_ERR(rndis_interf_group)) {
 948		rndis_free_inst(&opts->func_inst);
 949		return ERR_CAST(rndis_interf_group);
 950	}
 951	opts->rndis_interf_group = rndis_interf_group;
 952
 953	return &opts->func_inst;
 954}
 955
 956static void rndis_free(struct usb_function *f)
 957{
 958	struct f_rndis *rndis;
 959	struct f_rndis_opts *opts;
 960
 961	rndis = func_to_rndis(f);
 962	rndis_deregister(rndis->params);
 963	opts = container_of(f->fi, struct f_rndis_opts, func_inst);
 964	kfree(rndis);
 965	mutex_lock(&opts->lock);
 966	opts->refcnt--;
 967	mutex_unlock(&opts->lock);
 968}
 969
 970static void rndis_unbind(struct usb_configuration *c, struct usb_function *f)
 971{
 972	struct f_rndis		*rndis = func_to_rndis(f);
 973
 974	kfree(f->os_desc_table);
 975	f->os_desc_n = 0;
 976	usb_free_all_descriptors(f);
 977
 978	kfree(rndis->notify_req->buf);
 979	usb_ep_free_request(rndis->notify, rndis->notify_req);
 980}
 981
 982static struct usb_function *rndis_alloc(struct usb_function_instance *fi)
 983{
 984	struct f_rndis	*rndis;
 985	struct f_rndis_opts *opts;
 986	struct rndis_params *params;
 987
 988	/* allocate and initialize one new instance */
 989	rndis = kzalloc(sizeof(*rndis), GFP_KERNEL);
 990	if (!rndis)
 991		return ERR_PTR(-ENOMEM);
 992
 993	opts = container_of(fi, struct f_rndis_opts, func_inst);
 994	mutex_lock(&opts->lock);
 995	opts->refcnt++;
 996
 997	gether_get_host_addr_u8(opts->net, rndis->ethaddr);
 998	rndis->vendorID = opts->vendor_id;
 999	rndis->manufacturer = opts->manufacturer;
1000
1001	rndis->port.ioport = netdev_priv(opts->net);
1002	mutex_unlock(&opts->lock);
1003	/* RNDIS activates when the host changes this filter */
1004	rndis->port.cdc_filter = 0;
1005
1006	/* RNDIS has special (and complex) framing */
1007	rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
1008	rndis->port.wrap = rndis_add_header;
1009	rndis->port.unwrap = rndis_rm_hdr;
1010
1011	rndis->port.func.name = "rndis";
1012	/* descriptors are per-instance copies */
1013	rndis->port.func.bind = rndis_bind;
1014	rndis->port.func.unbind = rndis_unbind;
1015	rndis->port.func.set_alt = rndis_set_alt;
1016	rndis->port.func.setup = rndis_setup;
1017	rndis->port.func.disable = rndis_disable;
1018	rndis->port.func.free_func = rndis_free;
1019
1020	params = rndis_register(rndis_response_available, rndis);
1021	if (IS_ERR(params)) {
1022		kfree(rndis);
1023		return ERR_CAST(params);
1024	}
1025	rndis->params = params;
1026
1027	return &rndis->port.func;
1028}
1029
1030DECLARE_USB_FUNCTION_INIT(rndis, rndis_alloc_inst, rndis_alloc);
1031MODULE_LICENSE("GPL");
1032MODULE_AUTHOR("David Brownell");