drivers/usb/gadget/f_rndis.c

   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 (m.nazarewicz@samsung.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  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 /* #define VERBOSE_DEBUG */
  26
  27 #include <linux/slab.h>
  28 #include <linux/kernel.h>
  29 #include <linux/device.h>
  30 #include <linux/etherdevice.h>
  31
  32 #include <linux/atomic.h>
  33
  34 #include "u_ether.h"
  35 #include "rndis.h"
  36
  37
  38 /*
  39  * This function is an RNDIS Ethernet port -- a Microsoft protocol that's
  40  * been promoted instead of the standard CDC Ethernet.  The published RNDIS
  41  * spec is ambiguous, incomplete, and needlessly complex.  Variants such as
  42  * ActiveSync have even worse status in terms of specification.
  43  *
  44  * In short:  it's a protocol controlled by (and for) Microsoft, not for an
  45  * Open ecosystem or markets.  Linux supports it *only* because Microsoft
  46  * doesn't support the CDC Ethernet standard.
  47  *
  48  * The RNDIS data transfer model is complex, with multiple Ethernet packets
  49  * per USB message, and out of band data.  The control model is built around
  50  * what's essentially an "RNDIS RPC" protocol.  It's all wrapped in a CDC ACM
  51  * (modem, not Ethernet) veneer, with those ACM descriptors being entirely
  52  * useless (they're ignored).  RNDIS expects to be the only function in its
  53  * configuration, so it's no real help if you need composite devices; and
  54  * it expects to be the first configuration too.
  55  *
  56  * There is a single technical advantage of RNDIS over CDC Ethernet, if you
  57  * discount the fluff that its RPC can be made to deliver: it doesn't need
  58  * a NOP altsetting for the data interface.  That lets it work on some of the
  59  * "so smart it's stupid" hardware which takes over configuration changes
  60  * from the software, and adds restrictions like "no altsettings".
  61  *
  62  * Unfortunately MSFT's RNDIS drivers are buggy.  They hang or oops, and
  63  * have all sorts of contrary-to-specification oddities that can prevent
  64  * them from working sanely.  Since bugfixes (or accurate specs, letting
  65  * Linux work around those bugs) are unlikely to ever come from MSFT, you
  66  * may want to avoid using RNDIS on purely operational grounds.
  67  *
  68  * Omissions from the RNDIS 1.0 specification include:
  69  *
  70  *   - Power management ... references data that's scattered around lots
  71  *     of other documentation, which is incorrect/incomplete there too.
  72  *
  73  *   - There are various undocumented protocol requirements, like the need
  74  *     to send garbage in some control-OUT messages.
  75  *
  76  *   - MS-Windows drivers sometimes emit undocumented requests.
  77  */
  78
  79 struct f_rndis {
  80         struct gether                   port;
  81         u8                              ctrl_id, data_id;
  82         u8                              ethaddr[ETH_ALEN];
  83         int                             config;
  84
  85         struct usb_ep                   *notify;
  86         struct usb_request              *notify_req;
  87         atomic_t                        notify_count;
  88 };
  89
  90 static inline struct f_rndis *func_to_rndis(struct usb_function *f)
  91 {
  92         return container_of(f, struct f_rndis, port.func);
  93 }
  94
  95 /* peak (theoretical) bulk transfer rate in bits-per-second */
  96 static unsigned int bitrate(struct usb_gadget *g)
  97 {
  98         if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
  99                 return 13 * 1024 * 8 * 1000 * 8;
 100         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 101                 return 13 * 512 * 8 * 1000 * 8;
 102         else
 103                 return 19 * 64 * 1 * 1000 * 8;
 104 }
 105
 106 /*-------------------------------------------------------------------------*/
 107
 108 /*
 109  */
 110
 111 #define LOG2_STATUS_INTERVAL_MSEC       5       /* 1 << 5 == 32 msec */
 112 #define STATUS_BYTECOUNT                8       /* 8 bytes data */
 113
 114
 115 /* interface descriptor: */
 116
 117 static struct usb_interface_descriptor rndis_control_intf = {
 118         .bLength =              sizeof rndis_control_intf,
 119         .bDescriptorType =      USB_DT_INTERFACE,
 120
 121         /* .bInterfaceNumber = DYNAMIC */
 122         /* status endpoint is optional; this could be patched later */
 123         .bNumEndpoints =        1,
 124         .bInterfaceClass =      USB_CLASS_COMM,
 125         .bInterfaceSubClass =   USB_CDC_SUBCLASS_ACM,
 126         .bInterfaceProtocol =   USB_CDC_ACM_PROTO_VENDOR,
 127         /* .iInterface = DYNAMIC */
 128 };
 129
 130 static struct usb_cdc_header_desc header_desc = {
 131         .bLength =              sizeof header_desc,
 132         .bDescriptorType =      USB_DT_CS_INTERFACE,
 133         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 134
 135         .bcdCDC =               cpu_to_le16(0x0110),
 136 };
 137
 138 static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = {
 139         .bLength =              sizeof call_mgmt_descriptor,
 140         .bDescriptorType =      USB_DT_CS_INTERFACE,
 141         .bDescriptorSubType =   USB_CDC_CALL_MANAGEMENT_TYPE,
 142
 143         .bmCapabilities =       0x00,
 144         .bDataInterface =       0x01,
 145 };
 146
 147 static struct usb_cdc_acm_descriptor rndis_acm_descriptor = {
 148         .bLength =              sizeof rndis_acm_descriptor,
 149         .bDescriptorType =      USB_DT_CS_INTERFACE,
 150         .bDescriptorSubType =   USB_CDC_ACM_TYPE,
 151
 152         .bmCapabilities =       0x00,
 153 };
 154
 155 static struct usb_cdc_union_desc rndis_union_desc = {
 156         .bLength =              sizeof(rndis_union_desc),
 157         .bDescriptorType =      USB_DT_CS_INTERFACE,
 158         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 159         /* .bMasterInterface0 = DYNAMIC */
 160         /* .bSlaveInterface0 =  DYNAMIC */
 161 };
 162
 163 /* the data interface has two bulk endpoints */
 164
 165 static struct usb_interface_descriptor rndis_data_intf = {
 166         .bLength =              sizeof rndis_data_intf,
 167         .bDescriptorType =      USB_DT_INTERFACE,
 168
 169         /* .bInterfaceNumber = DYNAMIC */
 170         .bNumEndpoints =        2,
 171         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 172         .bInterfaceSubClass =   0,
 173         .bInterfaceProtocol =   0,
 174         /* .iInterface = DYNAMIC */
 175 };
 176
 177
 178 static struct usb_interface_assoc_descriptor
 179 rndis_iad_descriptor = {
 180         .bLength =              sizeof rndis_iad_descriptor,
 181         .bDescriptorType =      USB_DT_INTERFACE_ASSOCIATION,
 182
 183         .bFirstInterface =      0, /* XXX, hardcoded */
 184         .bInterfaceCount =      2,      // control + data
 185         .bFunctionClass =       USB_CLASS_COMM,
 186         .bFunctionSubClass =    USB_CDC_SUBCLASS_ETHERNET,
 187         .bFunctionProtocol =    USB_CDC_PROTO_NONE,
 188         /* .iFunction = DYNAMIC */
 189 };
 190
 191 /* full speed support: */
 192
 193 static struct usb_endpoint_descriptor fs_notify_desc = {
 194         .bLength =              USB_DT_ENDPOINT_SIZE,
 195         .bDescriptorType =      USB_DT_ENDPOINT,
 196
 197         .bEndpointAddress =     USB_DIR_IN,
 198         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 199         .wMaxPacketSize =       cpu_to_le16(STATUS_BYTECOUNT),
 200         .bInterval =            1 << LOG2_STATUS_INTERVAL_MSEC,
 201 };
 202
 203 static struct usb_endpoint_descriptor fs_in_desc = {
 204         .bLength =              USB_DT_ENDPOINT_SIZE,
 205         .bDescriptorType =      USB_DT_ENDPOINT,
 206
 207         .bEndpointAddress =     USB_DIR_IN,
 208         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 209 };
 210
 211 static struct usb_endpoint_descriptor fs_out_desc = {
 212         .bLength =              USB_DT_ENDPOINT_SIZE,
 213         .bDescriptorType =      USB_DT_ENDPOINT,
 214
 215         .bEndpointAddress =     USB_DIR_OUT,
 216         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 217 };
 218
 219 static struct usb_descriptor_header *eth_fs_function[] = {
 220         (struct usb_descriptor_header *) &rndis_iad_descriptor,
 221
 222         /* control interface matches ACM, not Ethernet */
 223         (struct usb_descriptor_header *) &rndis_control_intf,
 224         (struct usb_descriptor_header *) &header_desc,
 225         (struct usb_descriptor_header *) &call_mgmt_descriptor,
 226         (struct usb_descriptor_header *) &rndis_acm_descriptor,
 227         (struct usb_descriptor_header *) &rndis_union_desc,
 228         (struct usb_descriptor_header *) &fs_notify_desc,
 229
 230         /* data interface has no altsetting */
 231         (struct usb_descriptor_header *) &rndis_data_intf,
 232         (struct usb_descriptor_header *) &fs_in_desc,
 233         (struct usb_descriptor_header *) &fs_out_desc,
 234         NULL,
 235 };
 236
 237 /* high speed support: */
 238
 239 static struct usb_endpoint_descriptor hs_notify_desc = {
 240         .bLength =              USB_DT_ENDPOINT_SIZE,
 241         .bDescriptorType =      USB_DT_ENDPOINT,
 242
 243         .bEndpointAddress =     USB_DIR_IN,
 244         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 245         .wMaxPacketSize =       cpu_to_le16(STATUS_BYTECOUNT),
 246         .bInterval =            LOG2_STATUS_INTERVAL_MSEC + 4,
 247 };
 248
 249 static struct usb_endpoint_descriptor hs_in_desc = {
 250         .bLength =              USB_DT_ENDPOINT_SIZE,
 251         .bDescriptorType =      USB_DT_ENDPOINT,
 252
 253         .bEndpointAddress =     USB_DIR_IN,
 254         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 255         .wMaxPacketSize =       cpu_to_le16(512),
 256 };
 257
 258 static struct usb_endpoint_descriptor hs_out_desc = {
 259         .bLength =              USB_DT_ENDPOINT_SIZE,
 260         .bDescriptorType =      USB_DT_ENDPOINT,
 261
 262         .bEndpointAddress =     USB_DIR_OUT,
 263         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 264         .wMaxPacketSize =       cpu_to_le16(512),
 265 };
 266
 267 static struct usb_descriptor_header *eth_hs_function[] = {
 268         (struct usb_descriptor_header *) &rndis_iad_descriptor,
 269
 270         /* control interface matches ACM, not Ethernet */
 271         (struct usb_descriptor_header *) &rndis_control_intf,
 272         (struct usb_descriptor_header *) &header_desc,
 273         (struct usb_descriptor_header *) &call_mgmt_descriptor,
 274         (struct usb_descriptor_header *) &rndis_acm_descriptor,
 275         (struct usb_descriptor_header *) &rndis_union_desc,
 276         (struct usb_descriptor_header *) &hs_notify_desc,
 277
 278         /* data interface has no altsetting */
 279         (struct usb_descriptor_header *) &rndis_data_intf,
 280         (struct usb_descriptor_header *) &hs_in_desc,
 281         (struct usb_descriptor_header *) &hs_out_desc,
 282         NULL,
 283 };
 284
 285 /* super speed support: */
 286
 287 static struct usb_endpoint_descriptor ss_notify_desc = {
 288         .bLength =              USB_DT_ENDPOINT_SIZE,
 289         .bDescriptorType =      USB_DT_ENDPOINT,
 290
 291         .bEndpointAddress =     USB_DIR_IN,
 292         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 293         .wMaxPacketSize =       cpu_to_le16(STATUS_BYTECOUNT),
 294         .bInterval =            LOG2_STATUS_INTERVAL_MSEC + 4,
 295 };
 296
 297 static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = {
 298         .bLength =              sizeof ss_intr_comp_desc,
 299         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 300
 301         /* the following 3 values can be tweaked if necessary */
 302         /* .bMaxBurst =         0, */
 303         /* .bmAttributes =      0, */
 304         .wBytesPerInterval =    cpu_to_le16(STATUS_BYTECOUNT),
 305 };
 306
 307 static struct usb_endpoint_descriptor ss_in_desc = {
 308         .bLength =              USB_DT_ENDPOINT_SIZE,
 309         .bDescriptorType =      USB_DT_ENDPOINT,
 310
 311         .bEndpointAddress =     USB_DIR_IN,
 312         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 313         .wMaxPacketSize =       cpu_to_le16(1024),
 314 };
 315
 316 static struct usb_endpoint_descriptor ss_out_desc = {
 317         .bLength =              USB_DT_ENDPOINT_SIZE,
 318         .bDescriptorType =      USB_DT_ENDPOINT,
 319
 320         .bEndpointAddress =     USB_DIR_OUT,
 321         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 322         .wMaxPacketSize =       cpu_to_le16(1024),
 323 };
 324
 325 static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = {
 326         .bLength =              sizeof ss_bulk_comp_desc,
 327         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 328
 329         /* the following 2 values can be tweaked if necessary */
 330         /* .bMaxBurst =         0, */
 331         /* .bmAttributes =      0, */
 332 };
 333
 334 static struct usb_descriptor_header *eth_ss_function[] = {
 335         (struct usb_descriptor_header *) &rndis_iad_descriptor,
 336
 337         /* control interface matches ACM, not Ethernet */
 338         (struct usb_descriptor_header *) &rndis_control_intf,
 339         (struct usb_descriptor_header *) &header_desc,
 340         (struct usb_descriptor_header *) &call_mgmt_descriptor,
 341         (struct usb_descriptor_header *) &rndis_acm_descriptor,
 342         (struct usb_descriptor_header *) &rndis_union_desc,
 343         (struct usb_descriptor_header *) &ss_notify_desc,
 344         (struct usb_descriptor_header *) &ss_intr_comp_desc,
 345
 346         /* data interface has no altsetting */
 347         (struct usb_descriptor_header *) &rndis_data_intf,
 348         (struct usb_descriptor_header *) &ss_in_desc,
 349         (struct usb_descriptor_header *) &ss_bulk_comp_desc,
 350         (struct usb_descriptor_header *) &ss_out_desc,
 351         (struct usb_descriptor_header *) &ss_bulk_comp_desc,
 352         NULL,
 353 };
 354
 355 /* string descriptors: */
 356
 357 static struct usb_string rndis_string_defs[] = {
 358         [0].s = "RNDIS Communications Control",
 359         [1].s = "RNDIS Ethernet Data",
 360         [2].s = "RNDIS",
 361         {  } /* end of list */
 362 };
 363
 364 static struct usb_gadget_strings rndis_string_table = {
 365         .language =             0x0409, /* en-us */
 366         .strings =              rndis_string_defs,
 367 };
 368
 369 static struct usb_gadget_strings *rndis_strings[] = {
 370         &rndis_string_table,
 371         NULL,
 372 };
 373
 374 /*-------------------------------------------------------------------------*/
 375
 376 static struct sk_buff *rndis_add_header(struct gether *port,
 377                                         struct sk_buff *skb)
 378 {
 379         struct sk_buff *skb2;
 380
 381         skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type));
 382         if (skb2)
 383                 rndis_add_hdr(skb2);
 384
 385         dev_kfree_skb_any(skb);
 386         return skb2;
 387 }
 388
 389 static void rndis_response_available(void *_rndis)
 390 {
 391         struct f_rndis                  *rndis = _rndis;
 392         struct usb_request              *req = rndis->notify_req;
 393         struct usb_composite_dev        *cdev = rndis->port.func.config->cdev;
 394         __le32                          *data = req->buf;
 395         int                             status;
 396
 397         if (atomic_inc_return(&rndis->notify_count) != 1)
 398                 return;
 399
 400         /* Send RNDIS RESPONSE_AVAILABLE notification; a
 401          * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too
 402          *
 403          * This is the only notification defined by RNDIS.
 404          */
 405         data[0] = cpu_to_le32(1);
 406         data[1] = cpu_to_le32(0);
 407
 408         status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
 409         if (status) {
 410                 atomic_dec(&rndis->notify_count);
 411                 DBG(cdev, "notify/0 --> %d\n", status);
 412         }
 413 }
 414
 415 static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req)
 416 {
 417         struct f_rndis                  *rndis = req->context;
 418         struct usb_composite_dev        *cdev = rndis->port.func.config->cdev;
 419         int                             status = req->status;
 420
 421         /* after TX:
 422          *  - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control)
 423          *  - RNDIS_RESPONSE_AVAILABLE (status/irq)
 424          */
 425         switch (status) {
 426         case -ECONNRESET:
 427         case -ESHUTDOWN:
 428                 /* connection gone */
 429                 atomic_set(&rndis->notify_count, 0);
 430                 break;
 431         default:
 432                 DBG(cdev, "RNDIS %s response error %d, %d/%d\n",
 433                         ep->name, status,
 434                         req->actual, req->length);
 435                 /* FALLTHROUGH */
 436         case 0:
 437                 if (ep != rndis->notify)
 438                         break;
 439
 440                 /* handle multiple pending RNDIS_RESPONSE_AVAILABLE
 441                  * notifications by resending until we're done
 442                  */
 443                 if (atomic_dec_and_test(&rndis->notify_count))
 444                         break;
 445                 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC);
 446                 if (status) {
 447                         atomic_dec(&rndis->notify_count);
 448                         DBG(cdev, "notify/1 --> %d\n", status);
 449                 }
 450                 break;
 451         }
 452 }
 453
 454 static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req)
 455 {
 456         struct f_rndis                  *rndis = req->context;
 457         struct usb_composite_dev        *cdev = rndis->port.func.config->cdev;
 458         int                             status;
 459
 460         /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */
 461 //      spin_lock(&dev->lock);
 462         status = rndis_msg_parser(rndis->config, (u8 *) req->buf);
 463         if (status < 0)
 464                 ERROR(cdev, "RNDIS command error %d, %d/%d\n",
 465                         status, req->actual, req->length);
 466 //      spin_unlock(&dev->lock);
 467 }
 468
 469 static int
 470 rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 471 {
 472         struct f_rndis          *rndis = func_to_rndis(f);
 473         struct usb_composite_dev *cdev = f->config->cdev;
 474         struct usb_request      *req = cdev->req;
 475         int                     value = -EOPNOTSUPP;
 476         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 477         u16                     w_value = le16_to_cpu(ctrl->wValue);
 478         u16                     w_length = le16_to_cpu(ctrl->wLength);
 479
 480         /* composite driver infrastructure handles everything except
 481          * CDC class messages; interface activation uses set_alt().
 482          */
 483         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 484
 485         /* RNDIS uses the CDC command encapsulation mechanism to implement
 486          * an RPC scheme, with much getting/setting of attributes by OID.
 487          */
 488         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 489                         | USB_CDC_SEND_ENCAPSULATED_COMMAND:
 490                 if (w_value || w_index != rndis->ctrl_id)
 491                         goto invalid;
 492                 /* read the request; process it later */
 493                 value = w_length;
 494                 req->complete = rndis_command_complete;
 495                 req->context = rndis;
 496                 /* later, rndis_response_available() sends a notification */
 497                 break;
 498
 499         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 500                         | USB_CDC_GET_ENCAPSULATED_RESPONSE:
 501                 if (w_value || w_index != rndis->ctrl_id)
 502                         goto invalid;
 503                 else {
 504                         u8 *buf;
 505                         u32 n;
 506
 507                         /* return the result */
 508                         buf = rndis_get_next_response(rndis->config, &n);
 509                         if (buf) {
 510                                 memcpy(req->buf, buf, n);
 511                                 req->complete = rndis_response_complete;
 512                                 rndis_free_response(rndis->config, buf);
 513                                 value = n;
 514                         }
 515                         /* else stalls ... spec says to avoid that */
 516                 }
 517                 break;
 518
 519         default:
 520 invalid:
 521                 VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 522                         ctrl->bRequestType, ctrl->bRequest,
 523                         w_value, w_index, w_length);
 524         }
 525
 526         /* respond with data transfer or status phase? */
 527         if (value >= 0) {
 528                 DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n",
 529                         ctrl->bRequestType, ctrl->bRequest,
 530                         w_value, w_index, w_length);
 531                 req->zero = (value < w_length);
 532                 req->length = value;
 533                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 534                 if (value < 0)
 535                         ERROR(cdev, "rndis response on err %d\n", value);
 536         }
 537
 538         /* device either stalls (value < 0) or reports success */
 539         return value;
 540 }
 541
 542
 543 static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 544 {
 545         struct f_rndis          *rndis = func_to_rndis(f);
 546         struct usb_composite_dev *cdev = f->config->cdev;
 547
 548         /* we know alt == 0 */
 549
 550         if (intf == rndis->ctrl_id) {
 551                 if (rndis->notify->driver_data) {
 552                         VDBG(cdev, "reset rndis control %d\n", intf);
 553                         usb_ep_disable(rndis->notify);
 554                 }
 555                 if (!rndis->notify->desc) {
 556                         VDBG(cdev, "init rndis ctrl %d\n", intf);
 557                         if (config_ep_by_speed(cdev->gadget, f, rndis->notify))
 558                                 goto fail;
 559                 }
 560                 usb_ep_enable(rndis->notify);
 561                 rndis->notify->driver_data = rndis;
 562
 563         } else if (intf == rndis->data_id) {
 564                 struct net_device       *net;
 565
 566                 if (rndis->port.in_ep->driver_data) {
 567                         DBG(cdev, "reset rndis\n");
 568                         gether_disconnect(&rndis->port);
 569                 }
 570
 571                 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) {
 572                         DBG(cdev, "init rndis\n");
 573                         if (config_ep_by_speed(cdev->gadget, f,
 574                                                rndis->port.in_ep) ||
 575                             config_ep_by_speed(cdev->gadget, f,
 576                                                rndis->port.out_ep)) {
 577                                 rndis->port.in_ep->desc = NULL;
 578                                 rndis->port.out_ep->desc = NULL;
 579                                 goto fail;
 580                         }
 581                 }
 582
 583                 /* Avoid ZLPs; they can be troublesome. */
 584                 rndis->port.is_zlp_ok = false;
 585
 586                 /* RNDIS should be in the "RNDIS uninitialized" state,
 587                  * either never activated or after rndis_uninit().
 588                  *
 589                  * We don't want data to flow here until a nonzero packet
 590                  * filter is set, at which point it enters "RNDIS data
 591                  * initialized" state ... but we do want the endpoints
 592                  * to be activated.  It's a strange little state.
 593                  *
 594                  * REVISIT the RNDIS gadget code has done this wrong for a
 595                  * very long time.  We need another call to the link layer
 596                  * code -- gether_updown(...bool) maybe -- to do it right.
 597                  */
 598                 rndis->port.cdc_filter = 0;
 599
 600                 DBG(cdev, "RNDIS RX/TX early activation ... \n");
 601                 net = gether_connect(&rndis->port);
 602                 if (IS_ERR(net))
 603                         return PTR_ERR(net);
 604
 605                 rndis_set_param_dev(rndis->config, net,
 606                                 &rndis->port.cdc_filter);
 607         } else
 608                 goto fail;
 609
 610         return 0;
 611 fail:
 612         return -EINVAL;
 613 }
 614
 615 static void rndis_disable(struct usb_function *f)
 616 {
 617         struct f_rndis          *rndis = func_to_rndis(f);
 618         struct usb_composite_dev *cdev = f->config->cdev;
 619
 620         if (!rndis->notify->driver_data)
 621                 return;
 622
 623         DBG(cdev, "rndis deactivated\n");
 624
 625         rndis_uninit(rndis->config);
 626         gether_disconnect(&rndis->port);
 627
 628         usb_ep_disable(rndis->notify);
 629         rndis->notify->driver_data = NULL;
 630 }
 631
 632 /*-------------------------------------------------------------------------*/
 633
 634 /*
 635  * This isn't quite the same mechanism as CDC Ethernet, since the
 636  * notification scheme passes less data, but the same set of link
 637  * states must be tested.  A key difference is that altsettings are
 638  * not used to tell whether the link should send packets or not.
 639  */
 640
 641 static void rndis_open(struct gether *geth)
 642 {
 643         struct f_rndis          *rndis = func_to_rndis(&geth->func);
 644         struct usb_composite_dev *cdev = geth->func.config->cdev;
 645
 646         DBG(cdev, "%s\n", __func__);
 647
 648         rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3,
 649                                 bitrate(cdev->gadget) / 100);
 650         rndis_signal_connect(rndis->config);
 651 }
 652
 653 static void rndis_close(struct gether *geth)
 654 {
 655         struct f_rndis          *rndis = func_to_rndis(&geth->func);
 656
 657         DBG(geth->func.config->cdev, "%s\n", __func__);
 658
 659         rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3, 0);
 660         rndis_signal_disconnect(rndis->config);
 661 }
 662
 663 /*-------------------------------------------------------------------------*/
 664
 665 /* ethernet function driver setup/binding */
 666
 667 static int
 668 rndis_bind(struct usb_configuration *c, struct usb_function *f)
 669 {
 670         struct usb_composite_dev *cdev = c->cdev;
 671         struct f_rndis          *rndis = func_to_rndis(f);
 672         int                     status;
 673         struct usb_ep           *ep;
 674
 675         /* allocate instance-specific interface IDs */
 676         status = usb_interface_id(c, f);
 677         if (status < 0)
 678                 goto fail;
 679         rndis->ctrl_id = status;
 680         rndis_iad_descriptor.bFirstInterface = status;
 681
 682         rndis_control_intf.bInterfaceNumber = status;
 683         rndis_union_desc.bMasterInterface0 = status;
 684
 685         status = usb_interface_id(c, f);
 686         if (status < 0)
 687                 goto fail;
 688         rndis->data_id = status;
 689
 690         rndis_data_intf.bInterfaceNumber = status;
 691         rndis_union_desc.bSlaveInterface0 = status;
 692
 693         status = -ENODEV;
 694
 695         /* allocate instance-specific endpoints */
 696         ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc);
 697         if (!ep)
 698                 goto fail;
 699         rndis->port.in_ep = ep;
 700         ep->driver_data = cdev; /* claim */
 701
 702         ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
 703         if (!ep)
 704                 goto fail;
 705         rndis->port.out_ep = ep;
 706         ep->driver_data = cdev; /* claim */
 707
 708         /* NOTE:  a status/notification endpoint is, strictly speaking,
 709          * optional.  We don't treat it that way though!  It's simpler,
 710          * and some newer profiles don't treat it as optional.
 711          */
 712         ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc);
 713         if (!ep)
 714                 goto fail;
 715         rndis->notify = ep;
 716         ep->driver_data = cdev; /* claim */
 717
 718         status = -ENOMEM;
 719
 720         /* allocate notification request and buffer */
 721         rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
 722         if (!rndis->notify_req)
 723                 goto fail;
 724         rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL);
 725         if (!rndis->notify_req->buf)
 726                 goto fail;
 727         rndis->notify_req->length = STATUS_BYTECOUNT;
 728         rndis->notify_req->context = rndis;
 729         rndis->notify_req->complete = rndis_response_complete;
 730
 731         /* copy descriptors, and track endpoint copies */
 732         f->descriptors = usb_copy_descriptors(eth_fs_function);
 733         if (!f->descriptors)
 734                 goto fail;
 735
 736         /* support all relevant hardware speeds... we expect that when
 737          * hardware is dual speed, all bulk-capable endpoints work at
 738          * both speeds
 739          */
 740         if (gadget_is_dualspeed(c->cdev->gadget)) {
 741                 hs_in_desc.bEndpointAddress =
 742                                 fs_in_desc.bEndpointAddress;
 743                 hs_out_desc.bEndpointAddress =
 744                                 fs_out_desc.bEndpointAddress;
 745                 hs_notify_desc.bEndpointAddress =
 746                                 fs_notify_desc.bEndpointAddress;
 747
 748                 /* copy descriptors, and track endpoint copies */
 749                 f->hs_descriptors = usb_copy_descriptors(eth_hs_function);
 750                 if (!f->hs_descriptors)
 751                         goto fail;
 752         }
 753
 754         if (gadget_is_superspeed(c->cdev->gadget)) {
 755                 ss_in_desc.bEndpointAddress =
 756                                 fs_in_desc.bEndpointAddress;
 757                 ss_out_desc.bEndpointAddress =
 758                                 fs_out_desc.bEndpointAddress;
 759                 ss_notify_desc.bEndpointAddress =
 760                                 fs_notify_desc.bEndpointAddress;
 761
 762                 /* copy descriptors, and track endpoint copies */
 763                 f->ss_descriptors = usb_copy_descriptors(eth_ss_function);
 764                 if (!f->ss_descriptors)
 765                         goto fail;
 766         }
 767
 768         rndis->port.open = rndis_open;
 769         rndis->port.close = rndis_close;
 770
 771         status = rndis_register(rndis_response_available, rndis);
 772         if (status < 0)
 773                 goto fail;
 774         rndis->config = status;
 775
 776         rndis_set_param_medium(rndis->config, NDIS_MEDIUM_802_3, 0);
 777         rndis_set_host_mac(rndis->config, rndis->ethaddr);
 778
 779 #if 0
 780 // FIXME
 781         if (rndis_set_param_vendor(rndis->config, vendorID,
 782                                 manufacturer))
 783                 goto fail0;
 784 #endif
 785
 786         /* NOTE:  all that is done without knowing or caring about
 787          * the network link ... which is unavailable to this code
 788          * until we're activated via set_alt().
 789          */
 790
 791         DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n",
 792                         gadget_is_superspeed(c->cdev->gadget) ? "super" :
 793                         gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
 794                         rndis->port.in_ep->name, rndis->port.out_ep->name,
 795                         rndis->notify->name);
 796         return 0;
 797
 798 fail:
 799         if (gadget_is_superspeed(c->cdev->gadget) && f->ss_descriptors)
 800                 usb_free_descriptors(f->ss_descriptors);
 801         if (gadget_is_dualspeed(c->cdev->gadget) && f->hs_descriptors)
 802                 usb_free_descriptors(f->hs_descriptors);
 803         if (f->descriptors)
 804                 usb_free_descriptors(f->descriptors);
 805
 806         if (rndis->notify_req) {
 807                 kfree(rndis->notify_req->buf);
 808                 usb_ep_free_request(rndis->notify, rndis->notify_req);
 809         }
 810
 811         /* we might as well release our claims on endpoints */
 812         if (rndis->notify)
 813                 rndis->notify->driver_data = NULL;
 814         if (rndis->port.out_ep->desc)
 815                 rndis->port.out_ep->driver_data = NULL;
 816         if (rndis->port.in_ep->desc)
 817                 rndis->port.in_ep->driver_data = NULL;
 818
 819         ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
 820
 821         return status;
 822 }
 823
 824 static void
 825 rndis_unbind(struct usb_configuration *c, struct usb_function *f)
 826 {
 827         struct f_rndis          *rndis = func_to_rndis(f);
 828
 829         rndis_deregister(rndis->config);
 830         rndis_exit();
 831
 832         if (gadget_is_superspeed(c->cdev->gadget))
 833                 usb_free_descriptors(f->ss_descriptors);
 834         if (gadget_is_dualspeed(c->cdev->gadget))
 835                 usb_free_descriptors(f->hs_descriptors);
 836         usb_free_descriptors(f->descriptors);
 837
 838         kfree(rndis->notify_req->buf);
 839         usb_ep_free_request(rndis->notify, rndis->notify_req);
 840
 841         kfree(rndis);
 842 }
 843
 844 /* Some controllers can't support RNDIS ... */
 845 static inline bool can_support_rndis(struct usb_configuration *c)
 846 {
 847         /* everything else is *presumably* fine */
 848         return true;
 849 }
 850
 851 /**
 852  * rndis_bind_config - add RNDIS network link to a configuration
 853  * @c: the configuration to support the network link
 854  * @ethaddr: a buffer in which the ethernet address of the host side
 855  *      side of the link was recorded
 856  * Context: single threaded during gadget setup
 857  *
 858  * Returns zero on success, else negative errno.
 859  *
 860  * Caller must have called @gether_setup().  Caller is also responsible
 861  * for calling @gether_cleanup() before module unload.
 862  */
 863 int
 864 rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
 865 {
 866         struct f_rndis  *rndis;
 867         int             status;
 868
 869         if (!can_support_rndis(c) || !ethaddr)
 870                 return -EINVAL;
 871
 872         /* maybe allocate device-global string IDs */
 873         if (rndis_string_defs[0].id == 0) {
 874
 875                 /* ... and setup RNDIS itself */
 876                 status = rndis_init();
 877                 if (status < 0)
 878                         return status;
 879
 880                 /* control interface label */
 881                 status = usb_string_id(c->cdev);
 882                 if (status < 0)
 883                         return status;
 884                 rndis_string_defs[0].id = status;
 885                 rndis_control_intf.iInterface = status;
 886
 887                 /* data interface label */
 888                 status = usb_string_id(c->cdev);
 889                 if (status < 0)
 890                         return status;
 891                 rndis_string_defs[1].id = status;
 892                 rndis_data_intf.iInterface = status;
 893
 894                 /* IAD iFunction label */
 895                 status = usb_string_id(c->cdev);
 896                 if (status < 0)
 897                         return status;
 898                 rndis_string_defs[2].id = status;
 899                 rndis_iad_descriptor.iFunction = status;
 900         }
 901
 902         /* allocate and initialize one new instance */
 903         status = -ENOMEM;
 904         rndis = kzalloc(sizeof *rndis, GFP_KERNEL);
 905         if (!rndis)
 906                 goto fail;
 907
 908         memcpy(rndis->ethaddr, ethaddr, ETH_ALEN);
 909
 910         /* RNDIS activates when the host changes this filter */
 911         rndis->port.cdc_filter = 0;
 912
 913         /* RNDIS has special (and complex) framing */
 914         rndis->port.header_len = sizeof(struct rndis_packet_msg_type);
 915         rndis->port.wrap = rndis_add_header;
 916         rndis->port.unwrap = rndis_rm_hdr;
 917
 918         rndis->port.func.name = "rndis";
 919         rndis->port.func.strings = rndis_strings;
 920         /* descriptors are per-instance copies */
 921         rndis->port.func.bind = rndis_bind;
 922         rndis->port.func.unbind = rndis_unbind;
 923         rndis->port.func.set_alt = rndis_set_alt;
 924         rndis->port.func.setup = rndis_setup;
 925         rndis->port.func.disable = rndis_disable;
 926
 927         status = usb_add_function(c, &rndis->port.func);
 928         if (status) {
 929                 kfree(rndis);
 930 fail:
 931                 rndis_exit();
 932         }
 933         return status;
 934 }