1 /* 2 * Net1080 based USB host-to-host cables 3 * Copyright (C) 2000-2005 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/init.h> 25 #include <linux/netdevice.h> 26 #include <linux/etherdevice.h> 27 #include <linux/ethtool.h> 28 #include <linux/workqueue.h> 29 #include <linux/mii.h> 30 #include <linux/usb.h> 31 #include <linux/usb/usbnet.h> 32 #include <linux/slab.h> 33 34 #include <asm/unaligned.h> 35 36 37 /* 38 * Netchip 1080 driver ... http://www.netchip.com 39 * (Sept 2004: End-of-life announcement has been sent.) 40 * Used in (some) LapLink cables 41 */ 42 43 #define frame_errors data[1] 44 45 /* 46 * NetChip framing of ethernet packets, supporting additional error 47 * checks for links that may drop bulk packets from inside messages. 48 * Odd USB length == always short read for last usb packet. 49 * - nc_header 50 * - Ethernet header (14 bytes) 51 * - payload 52 * - (optional padding byte, if needed so length becomes odd) 53 * - nc_trailer 54 * 55 * This framing is to be avoided for non-NetChip devices. 56 */ 57 58 struct nc_header { // packed: 59 __le16 hdr_len; // sizeof nc_header (LE, all) 60 __le16 packet_len; // payload size (including ethhdr) 61 __le16 packet_id; // detects dropped packets 62 #define MIN_HEADER 6 63 64 // all else is optional, and must start with: 65 // __le16 vendorId; // from usb-if 66 // __le16 productId; 67 } __packed; 68 69 #define PAD_BYTE ((unsigned char)0xAC) 70 71 struct nc_trailer { 72 __le16 packet_id; 73 } __packed; 74 75 // packets may use FLAG_FRAMING_NC and optional pad 76 #define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \ 77 + sizeof (struct ethhdr) \ 78 + (mtu) \ 79 + 1 \ 80 + sizeof (struct nc_trailer)) 81 82 #define MIN_FRAMED FRAMED_SIZE(0) 83 84 /* packets _could_ be up to 64KB... */ 85 #define NC_MAX_PACKET 32767 86 87 88 /* 89 * Zero means no timeout; else, how long a 64 byte bulk packet may be queued 90 * before the hardware drops it. If that's done, the driver will need to 91 * frame network packets to guard against the dropped USB packets. The win32 92 * driver sets this for both sides of the link. 93 */ 94 #define NC_READ_TTL_MS ((u8)255) // ms 95 96 /* 97 * We ignore most registers and EEPROM contents. 98 */ 99 #define REG_USBCTL ((u8)0x04) 100 #define REG_TTL ((u8)0x10) 101 #define REG_STATUS ((u8)0x11) 102 103 /* 104 * Vendor specific requests to read/write data 105 */ 106 #define REQUEST_REGISTER ((u8)0x10) 107 #define REQUEST_EEPROM ((u8)0x11) 108 109 static int 110 nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr) 111 { 112 int status = usb_control_msg(dev->udev, 113 usb_rcvctrlpipe(dev->udev, 0), 114 req, 115 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 116 0, regnum, 117 retval_ptr, sizeof *retval_ptr, 118 USB_CTRL_GET_TIMEOUT); 119 if (status > 0) 120 status = 0; 121 if (!status) 122 le16_to_cpus(retval_ptr); 123 return status; 124 } 125 126 static inline int 127 nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr) 128 { 129 return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr); 130 } 131 132 // no retval ... can become async, usable in_interrupt() 133 static void 134 nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value) 135 { 136 usb_control_msg(dev->udev, 137 usb_sndctrlpipe(dev->udev, 0), 138 req, 139 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 140 value, regnum, 141 NULL, 0, // data is in setup packet 142 USB_CTRL_SET_TIMEOUT); 143 } 144 145 static inline void 146 nc_register_write(struct usbnet *dev, u8 regnum, u16 value) 147 { 148 nc_vendor_write(dev, REQUEST_REGISTER, regnum, value); 149 } 150 151 152 #if 0 153 static void nc_dump_registers(struct usbnet *dev) 154 { 155 u8 reg; 156 u16 *vp = kmalloc(sizeof (u16)); 157 158 if (!vp) { 159 dbg("no memory?"); 160 return; 161 } 162 163 dbg("%s registers:", dev->net->name); 164 for (reg = 0; reg < 0x20; reg++) { 165 int retval; 166 167 // reading some registers is trouble 168 if (reg >= 0x08 && reg <= 0xf) 169 continue; 170 if (reg >= 0x12 && reg <= 0x1e) 171 continue; 172 173 retval = nc_register_read(dev, reg, vp); 174 if (retval < 0) 175 dbg("%s reg [0x%x] ==> error %d", 176 dev->net->name, reg, retval); 177 else 178 dbg("%s reg [0x%x] = 0x%x", 179 dev->net->name, reg, *vp); 180 } 181 kfree(vp); 182 } 183 #endif 184 185 186 /*-------------------------------------------------------------------------*/ 187 188 /* 189 * Control register 190 */ 191 192 #define USBCTL_WRITABLE_MASK 0x1f0f 193 // bits 15-13 reserved, r/o 194 #define USBCTL_ENABLE_LANG (1 << 12) 195 #define USBCTL_ENABLE_MFGR (1 << 11) 196 #define USBCTL_ENABLE_PROD (1 << 10) 197 #define USBCTL_ENABLE_SERIAL (1 << 9) 198 #define USBCTL_ENABLE_DEFAULTS (1 << 8) 199 // bits 7-4 reserved, r/o 200 #define USBCTL_FLUSH_OTHER (1 << 3) 201 #define USBCTL_FLUSH_THIS (1 << 2) 202 #define USBCTL_DISCONN_OTHER (1 << 1) 203 #define USBCTL_DISCONN_THIS (1 << 0) 204 205 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl) 206 { 207 netif_dbg(dev, link, dev->net, 208 "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n", 209 dev->udev->bus->bus_name, dev->udev->devpath, 210 usbctl, 211 (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "", 212 (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "", 213 (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "", 214 (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "", 215 (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "", 216 217 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "", 218 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "", 219 220 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "", 221 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "", 222 223 usbctl & ~USBCTL_WRITABLE_MASK); 224 } 225 226 /*-------------------------------------------------------------------------*/ 227 228 /* 229 * Status register 230 */ 231 232 #define STATUS_PORT_A (1 << 15) 233 234 #define STATUS_CONN_OTHER (1 << 14) 235 #define STATUS_SUSPEND_OTHER (1 << 13) 236 #define STATUS_MAILBOX_OTHER (1 << 12) 237 #define STATUS_PACKETS_OTHER(n) (((n) >> 8) & 0x03) 238 239 #define STATUS_CONN_THIS (1 << 6) 240 #define STATUS_SUSPEND_THIS (1 << 5) 241 #define STATUS_MAILBOX_THIS (1 << 4) 242 #define STATUS_PACKETS_THIS(n) (((n) >> 0) & 0x03) 243 244 #define STATUS_UNSPEC_MASK 0x0c8c 245 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK)) 246 247 248 static inline void nc_dump_status(struct usbnet *dev, u16 status) 249 { 250 netif_dbg(dev, link, dev->net, 251 "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n", 252 dev->udev->bus->bus_name, dev->udev->devpath, 253 status, 254 255 // XXX the packet counts don't seem right 256 // (1 at reset, not 0); maybe UNSPEC too 257 258 (status & STATUS_PORT_A) ? 'A' : 'B', 259 STATUS_PACKETS_THIS(status), 260 (status & STATUS_CONN_THIS) ? " CON" : "", 261 (status & STATUS_SUSPEND_THIS) ? " SUS" : "", 262 (status & STATUS_MAILBOX_THIS) ? " MBOX" : "", 263 264 STATUS_PACKETS_OTHER(status), 265 (status & STATUS_CONN_OTHER) ? " CON" : "", 266 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "", 267 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "", 268 269 status & STATUS_UNSPEC_MASK); 270 } 271 272 /*-------------------------------------------------------------------------*/ 273 274 /* 275 * TTL register 276 */ 277 278 #define TTL_THIS(ttl) (0x00ff & ttl) 279 #define TTL_OTHER(ttl) (0x00ff & (ttl >> 8)) 280 #define MK_TTL(this,other) ((u16)(((other)<<8)|(0x00ff&(this)))) 281 282 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl) 283 { 284 netif_dbg(dev, link, dev->net, "net1080 %s-%s ttl 0x%x this = %d, other = %d\n", 285 dev->udev->bus->bus_name, dev->udev->devpath, 286 ttl, TTL_THIS(ttl), TTL_OTHER(ttl)); 287 } 288 289 /*-------------------------------------------------------------------------*/ 290 291 static int net1080_reset(struct usbnet *dev) 292 { 293 u16 usbctl, status, ttl; 294 u16 *vp = kmalloc(sizeof (u16), GFP_KERNEL); 295 int retval; 296 297 if (!vp) 298 return -ENOMEM; 299 300 // nc_dump_registers(dev); 301 302 if ((retval = nc_register_read(dev, REG_STATUS, vp)) < 0) { 303 dbg("can't read %s-%s status: %d", 304 dev->udev->bus->bus_name, dev->udev->devpath, retval); 305 goto done; 306 } 307 status = *vp; 308 nc_dump_status(dev, status); 309 310 if ((retval = nc_register_read(dev, REG_USBCTL, vp)) < 0) { 311 dbg("can't read USBCTL, %d", retval); 312 goto done; 313 } 314 usbctl = *vp; 315 nc_dump_usbctl(dev, usbctl); 316 317 nc_register_write(dev, REG_USBCTL, 318 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER); 319 320 if ((retval = nc_register_read(dev, REG_TTL, vp)) < 0) { 321 dbg("can't read TTL, %d", retval); 322 goto done; 323 } 324 ttl = *vp; 325 // nc_dump_ttl(dev, ttl); 326 327 nc_register_write(dev, REG_TTL, 328 MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) ); 329 dbg("%s: assigned TTL, %d ms", dev->net->name, NC_READ_TTL_MS); 330 331 netif_info(dev, link, dev->net, "port %c, peer %sconnected\n", 332 (status & STATUS_PORT_A) ? 'A' : 'B', 333 (status & STATUS_CONN_OTHER) ? "" : "dis"); 334 retval = 0; 335 336 done: 337 kfree(vp); 338 return retval; 339 } 340 341 static int net1080_check_connect(struct usbnet *dev) 342 { 343 int retval; 344 u16 status; 345 u16 *vp = kmalloc(sizeof (u16), GFP_KERNEL); 346 347 if (!vp) 348 return -ENOMEM; 349 retval = nc_register_read(dev, REG_STATUS, vp); 350 status = *vp; 351 kfree(vp); 352 if (retval != 0) { 353 dbg("%s net1080_check_conn read - %d", dev->net->name, retval); 354 return retval; 355 } 356 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER) 357 return -ENOLINK; 358 return 0; 359 } 360 361 static void nc_flush_complete(struct urb *urb) 362 { 363 kfree(urb->context); 364 usb_free_urb(urb); 365 } 366 367 static void nc_ensure_sync(struct usbnet *dev) 368 { 369 dev->frame_errors++; 370 if (dev->frame_errors > 5) { 371 struct urb *urb; 372 struct usb_ctrlrequest *req; 373 int status; 374 375 /* Send a flush */ 376 urb = usb_alloc_urb(0, GFP_ATOMIC); 377 if (!urb) 378 return; 379 380 req = kmalloc(sizeof *req, GFP_ATOMIC); 381 if (!req) { 382 usb_free_urb(urb); 383 return; 384 } 385 386 req->bRequestType = USB_DIR_OUT 387 | USB_TYPE_VENDOR 388 | USB_RECIP_DEVICE; 389 req->bRequest = REQUEST_REGISTER; 390 req->wValue = cpu_to_le16(USBCTL_FLUSH_THIS 391 | USBCTL_FLUSH_OTHER); 392 req->wIndex = cpu_to_le16(REG_USBCTL); 393 req->wLength = cpu_to_le16(0); 394 395 /* queue an async control request, we don't need 396 * to do anything when it finishes except clean up. 397 */ 398 usb_fill_control_urb(urb, dev->udev, 399 usb_sndctrlpipe(dev->udev, 0), 400 (unsigned char *) req, 401 NULL, 0, 402 nc_flush_complete, req); 403 status = usb_submit_urb(urb, GFP_ATOMIC); 404 if (status) { 405 kfree(req); 406 usb_free_urb(urb); 407 return; 408 } 409 410 netif_dbg(dev, rx_err, dev->net, 411 "flush net1080; too many framing errors\n"); 412 dev->frame_errors = 0; 413 } 414 } 415 416 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 417 { 418 struct nc_header *header; 419 struct nc_trailer *trailer; 420 u16 hdr_len, packet_len; 421 422 if (!(skb->len & 0x01)) { 423 #ifdef DEBUG 424 struct net_device *net = dev->net; 425 dbg("rx framesize %d range %d..%d mtu %d", skb->len, 426 net->hard_header_len, dev->hard_mtu, net->mtu); 427 #endif 428 dev->net->stats.rx_frame_errors++; 429 nc_ensure_sync(dev); 430 return 0; 431 } 432 433 header = (struct nc_header *) skb->data; 434 hdr_len = le16_to_cpup(&header->hdr_len); 435 packet_len = le16_to_cpup(&header->packet_len); 436 if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) { 437 dev->net->stats.rx_frame_errors++; 438 dbg("packet too big, %d", packet_len); 439 nc_ensure_sync(dev); 440 return 0; 441 } else if (hdr_len < MIN_HEADER) { 442 dev->net->stats.rx_frame_errors++; 443 dbg("header too short, %d", hdr_len); 444 nc_ensure_sync(dev); 445 return 0; 446 } else if (hdr_len > MIN_HEADER) { 447 // out of band data for us? 448 dbg("header OOB, %d bytes", hdr_len - MIN_HEADER); 449 nc_ensure_sync(dev); 450 // switch (vendor/product ids) { ... } 451 } 452 skb_pull(skb, hdr_len); 453 454 trailer = (struct nc_trailer *) 455 (skb->data + skb->len - sizeof *trailer); 456 skb_trim(skb, skb->len - sizeof *trailer); 457 458 if ((packet_len & 0x01) == 0) { 459 if (skb->data [packet_len] != PAD_BYTE) { 460 dev->net->stats.rx_frame_errors++; 461 dbg("bad pad"); 462 return 0; 463 } 464 skb_trim(skb, skb->len - 1); 465 } 466 if (skb->len != packet_len) { 467 dev->net->stats.rx_frame_errors++; 468 dbg("bad packet len %d (expected %d)", 469 skb->len, packet_len); 470 nc_ensure_sync(dev); 471 return 0; 472 } 473 if (header->packet_id != get_unaligned(&trailer->packet_id)) { 474 dev->net->stats.rx_fifo_errors++; 475 dbg("(2+ dropped) rx packet_id mismatch 0x%x 0x%x", 476 le16_to_cpu(header->packet_id), 477 le16_to_cpu(trailer->packet_id)); 478 return 0; 479 } 480 #if 0 481 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len, 482 header->packet_len, header->packet_id); 483 #endif 484 dev->frame_errors = 0; 485 return 1; 486 } 487 488 static struct sk_buff * 489 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 490 { 491 struct sk_buff *skb2; 492 struct nc_header *header = NULL; 493 struct nc_trailer *trailer = NULL; 494 int padlen = sizeof (struct nc_trailer); 495 int len = skb->len; 496 497 if (!((len + padlen + sizeof (struct nc_header)) & 0x01)) 498 padlen++; 499 if (!skb_cloned(skb)) { 500 int headroom = skb_headroom(skb); 501 int tailroom = skb_tailroom(skb); 502 503 if (padlen <= tailroom && 504 sizeof(struct nc_header) <= headroom) 505 /* There's enough head and tail room */ 506 goto encapsulate; 507 508 if ((sizeof (struct nc_header) + padlen) < 509 (headroom + tailroom)) { 510 /* There's enough total room, so just readjust */ 511 skb->data = memmove(skb->head 512 + sizeof (struct nc_header), 513 skb->data, skb->len); 514 skb_set_tail_pointer(skb, len); 515 goto encapsulate; 516 } 517 } 518 519 /* Create a new skb to use with the correct size */ 520 skb2 = skb_copy_expand(skb, 521 sizeof (struct nc_header), 522 padlen, 523 flags); 524 dev_kfree_skb_any(skb); 525 if (!skb2) 526 return skb2; 527 skb = skb2; 528 529 encapsulate: 530 /* header first */ 531 header = (struct nc_header *) skb_push(skb, sizeof *header); 532 header->hdr_len = cpu_to_le16(sizeof (*header)); 533 header->packet_len = cpu_to_le16(len); 534 header->packet_id = cpu_to_le16((u16)dev->xid++); 535 536 /* maybe pad; then trailer */ 537 if (!((skb->len + sizeof *trailer) & 0x01)) 538 *skb_put(skb, 1) = PAD_BYTE; 539 trailer = (struct nc_trailer *) skb_put(skb, sizeof *trailer); 540 put_unaligned(header->packet_id, &trailer->packet_id); 541 #if 0 542 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n", 543 header->hdr_len, header->packet_len, 544 header->packet_id); 545 #endif 546 return skb; 547 } 548 549 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf) 550 { 551 unsigned extra = sizeof (struct nc_header) 552 + 1 553 + sizeof (struct nc_trailer); 554 555 dev->net->hard_header_len += extra; 556 dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu; 557 dev->hard_mtu = NC_MAX_PACKET; 558 return usbnet_get_endpoints (dev, intf); 559 } 560 561 static const struct driver_info net1080_info = { 562 .description = "NetChip TurboCONNECT", 563 .flags = FLAG_FRAMING_NC, 564 .bind = net1080_bind, 565 .reset = net1080_reset, 566 .check_connect = net1080_check_connect, 567 .rx_fixup = net1080_rx_fixup, 568 .tx_fixup = net1080_tx_fixup, 569 }; 570 571 static const struct usb_device_id products [] = { 572 { 573 USB_DEVICE(0x0525, 0x1080), // NetChip ref design 574 .driver_info = (unsigned long) &net1080_info, 575 }, { 576 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold 577 .driver_info = (unsigned long) &net1080_info, 578 }, 579 { }, // END 580 }; 581 MODULE_DEVICE_TABLE(usb, products); 582 583 static struct usb_driver net1080_driver = { 584 .name = "net1080", 585 .id_table = products, 586 .probe = usbnet_probe, 587 .disconnect = usbnet_disconnect, 588 .suspend = usbnet_suspend, 589 .resume = usbnet_resume, 590 }; 591 592 static int __init net1080_init(void) 593 { 594 return usb_register(&net1080_driver); 595 } 596 module_init(net1080_init); 597 598 static void __exit net1080_exit(void) 599 { 600 usb_deregister(&net1080_driver); 601 } 602 module_exit(net1080_exit); 603 604 MODULE_AUTHOR("David Brownell"); 605 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links"); 606 MODULE_LICENSE("GPL"); 607