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