drivers/usb/net/cdc_ether.c

   1 /*
   2  * CDC Ethernet based networking peripherals
   3  * Copyright (C) 2003-2005 by David Brownell
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 // #define      DEBUG                   // error path messages, extra info
  21 // #define      VERBOSE                 // more; success messages
  22
  23 #include <linux/module.h>
  24 #include <linux/sched.h>
  25 #include <linux/init.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/ctype.h>
  29 #include <linux/ethtool.h>
  30 #include <linux/workqueue.h>
  31 #include <linux/mii.h>
  32 #include <linux/usb.h>
  33 #include <linux/usb/cdc.h>
  34
  35 #include "usbnet.h"
  36
  37
  38 /*
  39  * probes control interface, claims data interface, collects the bulk
  40  * endpoints, activates data interface (if needed), maybe sets MTU.
  41  * all pure cdc, except for certain firmware workarounds, and knowing
  42  * that rndis uses one different rule.
  43  */
  44 int usbnet_generic_cdc_bind(struct usbnet *dev, struct usb_interface *intf)
  45 {
  46         u8                              *buf = intf->cur_altsetting->extra;
  47         int                             len = intf->cur_altsetting->extralen;
  48         struct usb_interface_descriptor *d;
  49         struct cdc_state                *info = (void *) &dev->data;
  50         int                             status;
  51         int                             rndis;
  52         struct usb_driver               *driver = driver_of(intf);
  53
  54         if (sizeof dev->data < sizeof *info)
  55                 return -EDOM;
  56
  57         /* expect strict spec conformance for the descriptors, but
  58          * cope with firmware which stores them in the wrong place
  59          */
  60         if (len == 0 && dev->udev->actconfig->extralen) {
  61                 /* Motorola SB4100 (and others: Brad Hards says it's
  62                  * from a Broadcom design) put CDC descriptors here
  63                  */
  64                 buf = dev->udev->actconfig->extra;
  65                 len = dev->udev->actconfig->extralen;
  66                 if (len)
  67                         dev_dbg(&intf->dev,
  68                                 "CDC descriptors on config\n");
  69         }
  70
  71         /* this assumes that if there's a non-RNDIS vendor variant
  72          * of cdc-acm, it'll fail RNDIS requests cleanly.
  73          */
  74         rndis = (intf->cur_altsetting->desc.bInterfaceProtocol == 0xff);
  75
  76         memset(info, 0, sizeof *info);
  77         info->control = intf;
  78         while (len > 3) {
  79                 if (buf [1] != USB_DT_CS_INTERFACE)
  80                         goto next_desc;
  81
  82                 /* use bDescriptorSubType to identify the CDC descriptors.
  83                  * We expect devices with CDC header and union descriptors.
  84                  * For CDC Ethernet we need the ethernet descriptor.
  85                  * For RNDIS, ignore two (pointless) CDC modem descriptors
  86                  * in favor of a complicated OID-based RPC scheme doing what
  87                  * CDC Ethernet achieves with a simple descriptor.
  88                  */
  89                 switch (buf [2]) {
  90                 case USB_CDC_HEADER_TYPE:
  91                         if (info->header) {
  92                                 dev_dbg(&intf->dev, "extra CDC header\n");
  93                                 goto bad_desc;
  94                         }
  95                         info->header = (void *) buf;
  96                         if (info->header->bLength != sizeof *info->header) {
  97                                 dev_dbg(&intf->dev, "CDC header len %u\n",
  98                                         info->header->bLength);
  99                                 goto bad_desc;
 100                         }
 101                         break;
 102                 case USB_CDC_UNION_TYPE:
 103                         if (info->u) {
 104                                 dev_dbg(&intf->dev, "extra CDC union\n");
 105                                 goto bad_desc;
 106                         }
 107                         info->u = (void *) buf;
 108                         if (info->u->bLength != sizeof *info->u) {
 109                                 dev_dbg(&intf->dev, "CDC union len %u\n",
 110                                         info->u->bLength);
 111                                 goto bad_desc;
 112                         }
 113
 114                         /* we need a master/control interface (what we're
 115                          * probed with) and a slave/data interface; union
 116                          * descriptors sort this all out.
 117                          */
 118                         info->control = usb_ifnum_to_if(dev->udev,
 119                                                 info->u->bMasterInterface0);
 120                         info->data = usb_ifnum_to_if(dev->udev,
 121                                                 info->u->bSlaveInterface0);
 122                         if (!info->control || !info->data) {
 123                                 dev_dbg(&intf->dev,
 124                                         "master #%u/%p slave #%u/%p\n",
 125                                         info->u->bMasterInterface0,
 126                                         info->control,
 127                                         info->u->bSlaveInterface0,
 128                                         info->data);
 129                                 goto bad_desc;
 130                         }
 131                         if (info->control != intf) {
 132                                 dev_dbg(&intf->dev, "bogus CDC Union\n");
 133                                 /* Ambit USB Cable Modem (and maybe others)
 134                                  * interchanges master and slave interface.
 135                                  */
 136                                 if (info->data == intf) {
 137                                         info->data = info->control;
 138                                         info->control = intf;
 139                                 } else
 140                                         goto bad_desc;
 141                         }
 142
 143                         /* a data interface altsetting does the real i/o */
 144                         d = &info->data->cur_altsetting->desc;
 145                         if (d->bInterfaceClass != USB_CLASS_CDC_DATA) {
 146                                 dev_dbg(&intf->dev, "slave class %u\n",
 147                                         d->bInterfaceClass);
 148                                 goto bad_desc;
 149                         }
 150                         break;
 151                 case USB_CDC_ETHERNET_TYPE:
 152                         if (info->ether) {
 153                                 dev_dbg(&intf->dev, "extra CDC ether\n");
 154                                 goto bad_desc;
 155                         }
 156                         info->ether = (void *) buf;
 157                         if (info->ether->bLength != sizeof *info->ether) {
 158                                 dev_dbg(&intf->dev, "CDC ether len %u\n",
 159                                         info->ether->bLength);
 160                                 goto bad_desc;
 161                         }
 162                         dev->hard_mtu = le16_to_cpu(
 163                                                 info->ether->wMaxSegmentSize);
 164                         /* because of Zaurus, we may be ignoring the host
 165                          * side link address we were given.
 166                          */
 167                         break;
 168                 }
 169 next_desc:
 170                 len -= buf [0]; /* bLength */
 171                 buf += buf [0];
 172         }
 173
 174         if (!info->header || !info->u || (!rndis && !info->ether)) {
 175                 dev_dbg(&intf->dev, "missing cdc %s%s%sdescriptor\n",
 176                         info->header ? "" : "header ",
 177                         info->u ? "" : "union ",
 178                         info->ether ? "" : "ether ");
 179                 goto bad_desc;
 180         }
 181
 182         /* claim data interface and set it up ... with side effects.
 183          * network traffic can't flow until an altsetting is enabled.
 184          */
 185         status = usb_driver_claim_interface(driver, info->data, dev);
 186         if (status < 0)
 187                 return status;
 188         status = usbnet_get_endpoints(dev, info->data);
 189         if (status < 0) {
 190                 /* ensure immediate exit from usbnet_disconnect */
 191                 usb_set_intfdata(info->data, NULL);
 192                 usb_driver_release_interface(driver, info->data);
 193                 return status;
 194         }
 195
 196         /* status endpoint: optional for CDC Ethernet, not RNDIS (or ACM) */
 197         dev->status = NULL;
 198         if (info->control->cur_altsetting->desc.bNumEndpoints == 1) {
 199                 struct usb_endpoint_descriptor  *desc;
 200
 201                 dev->status = &info->control->cur_altsetting->endpoint [0];
 202                 desc = &dev->status->desc;
 203                 if (!usb_endpoint_is_int_in(desc)
 204                                 || (le16_to_cpu(desc->wMaxPacketSize)
 205                                         < sizeof(struct usb_cdc_notification))
 206                                 || !desc->bInterval) {
 207                         dev_dbg(&intf->dev, "bad notification endpoint\n");
 208                         dev->status = NULL;
 209                 }
 210         }
 211         if (rndis && !dev->status) {
 212                 dev_dbg(&intf->dev, "missing RNDIS status endpoint\n");
 213                 usb_set_intfdata(info->data, NULL);
 214                 usb_driver_release_interface(driver, info->data);
 215                 return -ENODEV;
 216         }
 217         return 0;
 218
 219 bad_desc:
 220         dev_info(&dev->udev->dev, "bad CDC descriptors\n");
 221         return -ENODEV;
 222 }
 223 EXPORT_SYMBOL_GPL(usbnet_generic_cdc_bind);
 224
 225 void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
 226 {
 227         struct cdc_state                *info = (void *) &dev->data;
 228         struct usb_driver               *driver = driver_of(intf);
 229
 230         /* disconnect master --> disconnect slave */
 231         if (intf == info->control && info->data) {
 232                 /* ensure immediate exit from usbnet_disconnect */
 233                 usb_set_intfdata(info->data, NULL);
 234                 usb_driver_release_interface(driver, info->data);
 235                 info->data = NULL;
 236         }
 237
 238         /* and vice versa (just in case) */
 239         else if (intf == info->data && info->control) {
 240                 /* ensure immediate exit from usbnet_disconnect */
 241                 usb_set_intfdata(info->control, NULL);
 242                 usb_driver_release_interface(driver, info->control);
 243                 info->control = NULL;
 244         }
 245 }
 246 EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
 247
 248 \f
 249 /*-------------------------------------------------------------------------
 250  *
 251  * Communications Device Class, Ethernet Control model
 252  *
 253  * Takes two interfaces.  The DATA interface is inactive till an altsetting
 254  * is selected.  Configuration data includes class descriptors.  There's
 255  * an optional status endpoint on the control interface.
 256  *
 257  * This should interop with whatever the 2.4 "CDCEther.c" driver
 258  * (by Brad Hards) talked with, with more functionality.
 259  *
 260  *-------------------------------------------------------------------------*/
 261
 262 static void dumpspeed(struct usbnet *dev, __le32 *speeds)
 263 {
 264         if (netif_msg_timer(dev))
 265                 devinfo(dev, "link speeds: %u kbps up, %u kbps down",
 266                         __le32_to_cpu(speeds[0]) / 1000,
 267                 __le32_to_cpu(speeds[1]) / 1000);
 268 }
 269
 270 static void cdc_status(struct usbnet *dev, struct urb *urb)
 271 {
 272         struct usb_cdc_notification     *event;
 273
 274         if (urb->actual_length < sizeof *event)
 275                 return;
 276
 277         /* SPEED_CHANGE can get split into two 8-byte packets */
 278         if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
 279                 dumpspeed(dev, (__le32 *) urb->transfer_buffer);
 280                 return;
 281         }
 282
 283         event = urb->transfer_buffer;
 284         switch (event->bNotificationType) {
 285         case USB_CDC_NOTIFY_NETWORK_CONNECTION:
 286                 if (netif_msg_timer(dev))
 287                         devdbg(dev, "CDC: carrier %s",
 288                                         event->wValue ? "on" : "off");
 289                 if (event->wValue)
 290                         netif_carrier_on(dev->net);
 291                 else
 292                         netif_carrier_off(dev->net);
 293                 break;
 294         case USB_CDC_NOTIFY_SPEED_CHANGE:       /* tx/rx rates */
 295                 if (netif_msg_timer(dev))
 296                         devdbg(dev, "CDC: speed change (len %d)",
 297                                         urb->actual_length);
 298                 if (urb->actual_length != (sizeof *event + 8))
 299                         set_bit(EVENT_STS_SPLIT, &dev->flags);
 300                 else
 301                         dumpspeed(dev, (__le32 *) &event[1]);
 302                 break;
 303         /* USB_CDC_NOTIFY_RESPONSE_AVAILABLE can happen too (e.g. RNDIS),
 304          * but there are no standard formats for the response data.
 305          */
 306         default:
 307                 deverr(dev, "CDC: unexpected notification %02x!",
 308                                  event->bNotificationType);
 309                 break;
 310         }
 311 }
 312
 313 static u8 nibble(unsigned char c)
 314 {
 315         if (likely(isdigit(c)))
 316                 return c - '0';
 317         c = toupper(c);
 318         if (likely(isxdigit(c)))
 319                 return 10 + c - 'A';
 320         return 0;
 321 }
 322
 323 static inline int
 324 get_ethernet_addr(struct usbnet *dev, struct usb_cdc_ether_desc *e)
 325 {
 326         int             tmp, i;
 327         unsigned char   buf [13];
 328
 329         tmp = usb_string(dev->udev, e->iMACAddress, buf, sizeof buf);
 330         if (tmp != 12) {
 331                 dev_dbg(&dev->udev->dev,
 332                         "bad MAC string %d fetch, %d\n", e->iMACAddress, tmp);
 333                 if (tmp >= 0)
 334                         tmp = -EINVAL;
 335                 return tmp;
 336         }
 337         for (i = tmp = 0; i < 6; i++, tmp += 2)
 338                 dev->net->dev_addr [i] =
 339                         (nibble(buf [tmp]) << 4) + nibble(buf [tmp + 1]);
 340         return 0;
 341 }
 342
 343 static int cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 344 {
 345         int                             status;
 346         struct cdc_state                *info = (void *) &dev->data;
 347
 348         status = usbnet_generic_cdc_bind(dev, intf);
 349         if (status < 0)
 350                 return status;
 351
 352         status = get_ethernet_addr(dev, info->ether);
 353         if (status < 0) {
 354                 usb_set_intfdata(info->data, NULL);
 355                 usb_driver_release_interface(driver_of(intf), info->data);
 356                 return status;
 357         }
 358
 359         /* FIXME cdc-ether has some multicast code too, though it complains
 360          * in routine cases.  info->ether describes the multicast support.
 361          * Implement that here, manipulating the cdc filter as needed.
 362          */
 363         return 0;
 364 }
 365
 366 static const struct driver_info cdc_info = {
 367         .description =  "CDC Ethernet Device",
 368         .flags =        FLAG_ETHER,
 369         // .check_connect = cdc_check_connect,
 370         .bind =         cdc_bind,
 371         .unbind =       usbnet_cdc_unbind,
 372         .status =       cdc_status,
 373 };
 374
 375 /*-------------------------------------------------------------------------*/
 376
 377
 378 static const struct usb_device_id       products [] = {
 379 /*
 380  * BLACKLIST !!
 381  *
 382  * First blacklist any products that are egregiously nonconformant
 383  * with the CDC Ethernet specs.  Minor braindamage we cope with; when
 384  * they're not even trying, needing a separate driver is only the first
 385  * of the differences to show up.
 386  */
 387
 388 #define ZAURUS_MASTER_INTERFACE \
 389         .bInterfaceClass        = USB_CLASS_COMM, \
 390         .bInterfaceSubClass     = USB_CDC_SUBCLASS_ETHERNET, \
 391         .bInterfaceProtocol     = USB_CDC_PROTO_NONE
 392
 393 /* SA-1100 based Sharp Zaurus ("collie"), or compatible;
 394  * wire-incompatible with true CDC Ethernet implementations.
 395  * (And, it seems, needlessly so...)
 396  */
 397 {
 398         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 399                           | USB_DEVICE_ID_MATCH_DEVICE,
 400         .idVendor               = 0x04DD,
 401         .idProduct              = 0x8004,
 402         ZAURUS_MASTER_INTERFACE,
 403         .driver_info            = 0,
 404 },
 405
 406 /* PXA-25x based Sharp Zaurii.  Note that it seems some of these
 407  * (later models especially) may have shipped only with firmware
 408  * advertising false "CDC MDLM" compatibility ... but we're not
 409  * clear which models did that, so for now let's assume the worst.
 410  */
 411 {
 412         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 413                           | USB_DEVICE_ID_MATCH_DEVICE,
 414         .idVendor               = 0x04DD,
 415         .idProduct              = 0x8005,       /* A-300 */
 416         ZAURUS_MASTER_INTERFACE,
 417         .driver_info            = 0,
 418 }, {
 419         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 420                           | USB_DEVICE_ID_MATCH_DEVICE,
 421         .idVendor               = 0x04DD,
 422         .idProduct              = 0x8006,       /* B-500/SL-5600 */
 423         ZAURUS_MASTER_INTERFACE,
 424         .driver_info            = 0,
 425 }, {
 426         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 427                   | USB_DEVICE_ID_MATCH_DEVICE,
 428         .idVendor               = 0x04DD,
 429         .idProduct              = 0x8007,       /* C-700 */
 430         ZAURUS_MASTER_INTERFACE,
 431         .driver_info            = 0,
 432 }, {
 433         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 434                  | USB_DEVICE_ID_MATCH_DEVICE,
 435         .idVendor               = 0x04DD,
 436         .idProduct              = 0x9031,       /* C-750 C-760 */
 437         ZAURUS_MASTER_INTERFACE,
 438         .driver_info            = 0,
 439 }, {
 440         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 441                  | USB_DEVICE_ID_MATCH_DEVICE,
 442         .idVendor               = 0x04DD,
 443         .idProduct              = 0x9032,       /* SL-6000 */
 444         ZAURUS_MASTER_INTERFACE,
 445         .driver_info            = 0,
 446 }, {
 447         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 448                  | USB_DEVICE_ID_MATCH_DEVICE,
 449         .idVendor               = 0x04DD,
 450         /* reported with some C860 units */
 451         .idProduct              = 0x9050,       /* C-860 */
 452         ZAURUS_MASTER_INTERFACE,
 453         .driver_info            = 0,
 454 },
 455
 456 /* Olympus has some models with a Zaurus-compatible option.
 457  * R-1000 uses a FreeScale i.MXL cpu (ARMv4T)
 458  */
 459 {
 460         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 461                  | USB_DEVICE_ID_MATCH_DEVICE,
 462         .idVendor               = 0x07B4,
 463         .idProduct              = 0x0F02,       /* R-1000 */
 464         ZAURUS_MASTER_INTERFACE,
 465         .driver_info            = 0,
 466 },
 467
 468 /*
 469  * WHITELIST!!!
 470  *
 471  * CDC Ether uses two interfaces, not necessarily consecutive.
 472  * We match the main interface, ignoring the optional device
 473  * class so we could handle devices that aren't exclusively
 474  * CDC ether.
 475  *
 476  * NOTE:  this match must come AFTER entries blacklisting devices
 477  * because of bugs/quirks in a given product (like Zaurus, above).
 478  */
 479 {
 480         USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ETHERNET,
 481                         USB_CDC_PROTO_NONE),
 482         .driver_info = (unsigned long) &cdc_info,
 483 },
 484         { },            // END
 485 };
 486 MODULE_DEVICE_TABLE(usb, products);
 487
 488 static struct usb_driver cdc_driver = {
 489         .name =         "cdc_ether",
 490         .id_table =     products,
 491         .probe =        usbnet_probe,
 492         .disconnect =   usbnet_disconnect,
 493         .suspend =      usbnet_suspend,
 494         .resume =       usbnet_resume,
 495 };
 496
 497
 498 static int __init cdc_init(void)
 499 {
 500         BUILD_BUG_ON((sizeof(((struct usbnet *)0)->data)
 501                         < sizeof(struct cdc_state)));
 502
 503         return usb_register(&cdc_driver);
 504 }
 505 module_init(cdc_init);
 506
 507 static void __exit cdc_exit(void)
 508 {
 509         usb_deregister(&cdc_driver);
 510 }
 511 module_exit(cdc_exit);
 512
 513 MODULE_AUTHOR("David Brownell");
 514 MODULE_DESCRIPTION("USB CDC Ethernet devices");
 515 MODULE_LICENSE("GPL");