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 (desc->bmAttributes != USB_ENDPOINT_XFER_INT
 204                                 || !(desc->bEndpointAddress & USB_DIR_IN)
 205                                 || (le16_to_cpu(desc->wMaxPacketSize)
 206                                         < sizeof(struct usb_cdc_notification))
 207                                 || !desc->bInterval) {
 208                         dev_dbg(&intf->dev, "bad notification endpoint\n");
 209                         dev->status = NULL;
 210                 }
 211         }
 212         if (rndis && !dev->status) {
 213                 dev_dbg(&intf->dev, "missing RNDIS status endpoint\n");
 214                 usb_set_intfdata(info->data, NULL);
 215                 usb_driver_release_interface(driver, info->data);
 216                 return -ENODEV;
 217         }
 218         return 0;
 219
 220 bad_desc:
 221         dev_info(&dev->udev->dev, "bad CDC descriptors\n");
 222         return -ENODEV;
 223 }
 224 EXPORT_SYMBOL_GPL(usbnet_generic_cdc_bind);
 225
 226 void usbnet_cdc_unbind(struct usbnet *dev, struct usb_interface *intf)
 227 {
 228         struct cdc_state                *info = (void *) &dev->data;
 229         struct usb_driver               *driver = driver_of(intf);
 230
 231         /* disconnect master --> disconnect slave */
 232         if (intf == info->control && info->data) {
 233                 /* ensure immediate exit from usbnet_disconnect */
 234                 usb_set_intfdata(info->data, NULL);
 235                 usb_driver_release_interface(driver, info->data);
 236                 info->data = NULL;
 237         }
 238
 239         /* and vice versa (just in case) */
 240         else if (intf == info->data && info->control) {
 241                 /* ensure immediate exit from usbnet_disconnect */
 242                 usb_set_intfdata(info->control, NULL);
 243                 usb_driver_release_interface(driver, info->control);
 244                 info->control = NULL;
 245         }
 246 }
 247 EXPORT_SYMBOL_GPL(usbnet_cdc_unbind);
 248
 249 \f
 250 /*-------------------------------------------------------------------------
 251  *
 252  * Communications Device Class, Ethernet Control model
 253  *
 254  * Takes two interfaces.  The DATA interface is inactive till an altsetting
 255  * is selected.  Configuration data includes class descriptors.  There's
 256  * an optional status endpoint on the control interface.
 257  *
 258  * This should interop with whatever the 2.4 "CDCEther.c" driver
 259  * (by Brad Hards) talked with, with more functionality.
 260  *
 261  *-------------------------------------------------------------------------*/
 262
 263 static void dumpspeed(struct usbnet *dev, __le32 *speeds)
 264 {
 265         if (netif_msg_timer(dev))
 266                 devinfo(dev, "link speeds: %u kbps up, %u kbps down",
 267                         __le32_to_cpu(speeds[0]) / 1000,
 268                 __le32_to_cpu(speeds[1]) / 1000);
 269 }
 270
 271 static void cdc_status(struct usbnet *dev, struct urb *urb)
 272 {
 273         struct usb_cdc_notification     *event;
 274
 275         if (urb->actual_length < sizeof *event)
 276                 return;
 277
 278         /* SPEED_CHANGE can get split into two 8-byte packets */
 279         if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
 280                 dumpspeed(dev, (__le32 *) urb->transfer_buffer);
 281                 return;
 282         }
 283
 284         event = urb->transfer_buffer;
 285         switch (event->bNotificationType) {
 286         case USB_CDC_NOTIFY_NETWORK_CONNECTION:
 287                 if (netif_msg_timer(dev))
 288                         devdbg(dev, "CDC: carrier %s",
 289                                         event->wValue ? "on" : "off");
 290                 if (event->wValue)
 291                         netif_carrier_on(dev->net);
 292                 else
 293                         netif_carrier_off(dev->net);
 294                 break;
 295         case USB_CDC_NOTIFY_SPEED_CHANGE:       /* tx/rx rates */
 296                 if (netif_msg_timer(dev))
 297                         devdbg(dev, "CDC: speed change (len %d)",
 298                                         urb->actual_length);
 299                 if (urb->actual_length != (sizeof *event + 8))
 300                         set_bit(EVENT_STS_SPLIT, &dev->flags);
 301                 else
 302                         dumpspeed(dev, (__le32 *) &event[1]);
 303                 break;
 304         /* USB_CDC_NOTIFY_RESPONSE_AVAILABLE can happen too (e.g. RNDIS),
 305          * but there are no standard formats for the response data.
 306          */
 307         default:
 308                 deverr(dev, "CDC: unexpected notification %02x!",
 309                                  event->bNotificationType);
 310                 break;
 311         }
 312 }
 313
 314 static u8 nibble(unsigned char c)
 315 {
 316         if (likely(isdigit(c)))
 317                 return c - '0';
 318         c = toupper(c);
 319         if (likely(isxdigit(c)))
 320                 return 10 + c - 'A';
 321         return 0;
 322 }
 323
 324 static inline int
 325 get_ethernet_addr(struct usbnet *dev, struct usb_cdc_ether_desc *e)
 326 {
 327         int             tmp, i;
 328         unsigned char   buf [13];
 329
 330         tmp = usb_string(dev->udev, e->iMACAddress, buf, sizeof buf);
 331         if (tmp != 12) {
 332                 dev_dbg(&dev->udev->dev,
 333                         "bad MAC string %d fetch, %d\n", e->iMACAddress, tmp);
 334                 if (tmp >= 0)
 335                         tmp = -EINVAL;
 336                 return tmp;
 337         }
 338         for (i = tmp = 0; i < 6; i++, tmp += 2)
 339                 dev->net->dev_addr [i] =
 340                         (nibble(buf [tmp]) << 4) + nibble(buf [tmp + 1]);
 341         return 0;
 342 }
 343
 344 static int cdc_bind(struct usbnet *dev, struct usb_interface *intf)
 345 {
 346         int                             status;
 347         struct cdc_state                *info = (void *) &dev->data;
 348
 349         status = usbnet_generic_cdc_bind(dev, intf);
 350         if (status < 0)
 351                 return status;
 352
 353         status = get_ethernet_addr(dev, info->ether);
 354         if (status < 0) {
 355                 usb_set_intfdata(info->data, NULL);
 356                 usb_driver_release_interface(driver_of(intf), info->data);
 357                 return status;
 358         }
 359
 360         /* FIXME cdc-ether has some multicast code too, though it complains
 361          * in routine cases.  info->ether describes the multicast support.
 362          * Implement that here, manipulating the cdc filter as needed.
 363          */
 364         return 0;
 365 }
 366
 367 static const struct driver_info cdc_info = {
 368         .description =  "CDC Ethernet Device",
 369         .flags =        FLAG_ETHER,
 370         // .check_connect = cdc_check_connect,
 371         .bind =         cdc_bind,
 372         .unbind =       usbnet_cdc_unbind,
 373         .status =       cdc_status,
 374 };
 375
 376 /*-------------------------------------------------------------------------*/
 377
 378
 379 static const struct usb_device_id       products [] = {
 380 /*
 381  * BLACKLIST !!
 382  *
 383  * First blacklist any products that are egregiously nonconformant
 384  * with the CDC Ethernet specs.  Minor braindamage we cope with; when
 385  * they're not even trying, needing a separate driver is only the first
 386  * of the differences to show up.
 387  */
 388
 389 #define ZAURUS_MASTER_INTERFACE \
 390         .bInterfaceClass        = USB_CLASS_COMM, \
 391         .bInterfaceSubClass     = USB_CDC_SUBCLASS_ETHERNET, \
 392         .bInterfaceProtocol     = USB_CDC_PROTO_NONE
 393
 394 /* SA-1100 based Sharp Zaurus ("collie"), or compatible;
 395  * wire-incompatible with true CDC Ethernet implementations.
 396  * (And, it seems, needlessly so...)
 397  */
 398 {
 399         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 400                           | USB_DEVICE_ID_MATCH_DEVICE,
 401         .idVendor               = 0x04DD,
 402         .idProduct              = 0x8004,
 403         ZAURUS_MASTER_INTERFACE,
 404         .driver_info            = 0,
 405 },
 406
 407 /* PXA-25x based Sharp Zaurii.  Note that it seems some of these
 408  * (later models especially) may have shipped only with firmware
 409  * advertising false "CDC MDLM" compatibility ... but we're not
 410  * clear which models did that, so for now let's assume the worst.
 411  */
 412 {
 413         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 414                           | USB_DEVICE_ID_MATCH_DEVICE,
 415         .idVendor               = 0x04DD,
 416         .idProduct              = 0x8005,       /* A-300 */
 417         ZAURUS_MASTER_INTERFACE,
 418         .driver_info            = 0,
 419 }, {
 420         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 421                           | USB_DEVICE_ID_MATCH_DEVICE,
 422         .idVendor               = 0x04DD,
 423         .idProduct              = 0x8006,       /* B-500/SL-5600 */
 424         ZAURUS_MASTER_INTERFACE,
 425         .driver_info            = 0,
 426 }, {
 427         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 428                   | USB_DEVICE_ID_MATCH_DEVICE,
 429         .idVendor               = 0x04DD,
 430         .idProduct              = 0x8007,       /* C-700 */
 431         ZAURUS_MASTER_INTERFACE,
 432         .driver_info            = 0,
 433 }, {
 434         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 435                  | USB_DEVICE_ID_MATCH_DEVICE,
 436         .idVendor               = 0x04DD,
 437         .idProduct              = 0x9031,       /* C-750 C-760 */
 438         ZAURUS_MASTER_INTERFACE,
 439         .driver_info            = 0,
 440 }, {
 441         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 442                  | USB_DEVICE_ID_MATCH_DEVICE,
 443         .idVendor               = 0x04DD,
 444         .idProduct              = 0x9032,       /* SL-6000 */
 445         ZAURUS_MASTER_INTERFACE,
 446         .driver_info            = 0,
 447 }, {
 448         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 449                  | USB_DEVICE_ID_MATCH_DEVICE,
 450         .idVendor               = 0x04DD,
 451         /* reported with some C860 units */
 452         .idProduct              = 0x9050,       /* C-860 */
 453         ZAURUS_MASTER_INTERFACE,
 454         .driver_info            = 0,
 455 },
 456
 457 /* Olympus has some models with a Zaurus-compatible option.
 458  * R-1000 uses a FreeScale i.MXL cpu (ARMv4T)
 459  */
 460 {
 461         .match_flags    =   USB_DEVICE_ID_MATCH_INT_INFO
 462                  | USB_DEVICE_ID_MATCH_DEVICE,
 463         .idVendor               = 0x07B4,
 464         .idProduct              = 0x0F02,       /* R-1000 */
 465         ZAURUS_MASTER_INTERFACE,
 466         .driver_info            = 0,
 467 },
 468
 469 /*
 470  * WHITELIST!!!
 471  *
 472  * CDC Ether uses two interfaces, not necessarily consecutive.
 473  * We match the main interface, ignoring the optional device
 474  * class so we could handle devices that aren't exclusively
 475  * CDC ether.
 476  *
 477  * NOTE:  this match must come AFTER entries blacklisting devices
 478  * because of bugs/quirks in a given product (like Zaurus, above).
 479  */
 480 {
 481         USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ETHERNET,
 482                         USB_CDC_PROTO_NONE),
 483         .driver_info = (unsigned long) &cdc_info,
 484 },
 485         { },            // END
 486 };
 487 MODULE_DEVICE_TABLE(usb, products);
 488
 489 static struct usb_driver cdc_driver = {
 490         .name =         "cdc_ether",
 491         .id_table =     products,
 492         .probe =        usbnet_probe,
 493         .disconnect =   usbnet_disconnect,
 494         .suspend =      usbnet_suspend,
 495         .resume =       usbnet_resume,
 496 };
 497
 498
 499 static int __init cdc_init(void)
 500 {
 501         BUG_ON((sizeof(((struct usbnet *)0)->data)
 502                         < sizeof(struct cdc_state)));
 503
 504         return usb_register(&cdc_driver);
 505 }
 506 module_init(cdc_init);
 507
 508 static void __exit cdc_exit(void)
 509 {
 510         usb_deregister(&cdc_driver);
 511 }
 512 module_exit(cdc_exit);
 513
 514 MODULE_AUTHOR("David Brownell");
 515 MODULE_DESCRIPTION("USB CDC Ethernet devices");
 516 MODULE_LICENSE("GPL");