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