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 return; 160 161 netdev_dbg(dev->net, "registers:\n"); 162 for (reg = 0; reg < 0x20; reg++) { 163 int retval; 164 165 // reading some registers is trouble 166 if (reg >= 0x08 && reg <= 0xf) 167 continue; 168 if (reg >= 0x12 && reg <= 0x1e) 169 continue; 170 171 retval = nc_register_read(dev, reg, vp); 172 if (retval < 0) 173 netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n", 174 reg, retval); 175 else 176 netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp); 177 } 178 kfree(vp); 179 } 180 #endif 181 182 183 /*-------------------------------------------------------------------------*/ 184 185 /* 186 * Control register 187 */ 188 189 #define USBCTL_WRITABLE_MASK 0x1f0f 190 // bits 15-13 reserved, r/o 191 #define USBCTL_ENABLE_LANG (1 << 12) 192 #define USBCTL_ENABLE_MFGR (1 << 11) 193 #define USBCTL_ENABLE_PROD (1 << 10) 194 #define USBCTL_ENABLE_SERIAL (1 << 9) 195 #define USBCTL_ENABLE_DEFAULTS (1 << 8) 196 // bits 7-4 reserved, r/o 197 #define USBCTL_FLUSH_OTHER (1 << 3) 198 #define USBCTL_FLUSH_THIS (1 << 2) 199 #define USBCTL_DISCONN_OTHER (1 << 1) 200 #define USBCTL_DISCONN_THIS (1 << 0) 201 202 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl) 203 { 204 netif_dbg(dev, link, dev->net, 205 "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n", 206 dev->udev->bus->bus_name, dev->udev->devpath, 207 usbctl, 208 (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "", 209 (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "", 210 (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "", 211 (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "", 212 (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "", 213 214 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "", 215 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "", 216 217 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "", 218 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "", 219 220 usbctl & ~USBCTL_WRITABLE_MASK); 221 } 222 223 /*-------------------------------------------------------------------------*/ 224 225 /* 226 * Status register 227 */ 228 229 #define STATUS_PORT_A (1 << 15) 230 231 #define STATUS_CONN_OTHER (1 << 14) 232 #define STATUS_SUSPEND_OTHER (1 << 13) 233 #define STATUS_MAILBOX_OTHER (1 << 12) 234 #define STATUS_PACKETS_OTHER(n) (((n) >> 8) & 0x03) 235 236 #define STATUS_CONN_THIS (1 << 6) 237 #define STATUS_SUSPEND_THIS (1 << 5) 238 #define STATUS_MAILBOX_THIS (1 << 4) 239 #define STATUS_PACKETS_THIS(n) (((n) >> 0) & 0x03) 240 241 #define STATUS_UNSPEC_MASK 0x0c8c 242 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK)) 243 244 245 static inline void nc_dump_status(struct usbnet *dev, u16 status) 246 { 247 netif_dbg(dev, link, dev->net, 248 "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n", 249 dev->udev->bus->bus_name, dev->udev->devpath, 250 status, 251 252 // XXX the packet counts don't seem right 253 // (1 at reset, not 0); maybe UNSPEC too 254 255 (status & STATUS_PORT_A) ? 'A' : 'B', 256 STATUS_PACKETS_THIS(status), 257 (status & STATUS_CONN_THIS) ? " CON" : "", 258 (status & STATUS_SUSPEND_THIS) ? " SUS" : "", 259 (status & STATUS_MAILBOX_THIS) ? " MBOX" : "", 260 261 STATUS_PACKETS_OTHER(status), 262 (status & STATUS_CONN_OTHER) ? " CON" : "", 263 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "", 264 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "", 265 266 status & STATUS_UNSPEC_MASK); 267 } 268 269 /*-------------------------------------------------------------------------*/ 270 271 /* 272 * TTL register 273 */ 274 275 #define TTL_THIS(ttl) (0x00ff & ttl) 276 #define TTL_OTHER(ttl) (0x00ff & (ttl >> 8)) 277 #define MK_TTL(this,other) ((u16)(((other)<<8)|(0x00ff&(this)))) 278 279 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl) 280 { 281 netif_dbg(dev, link, dev->net, "net1080 %s-%s ttl 0x%x this = %d, other = %d\n", 282 dev->udev->bus->bus_name, dev->udev->devpath, 283 ttl, TTL_THIS(ttl), TTL_OTHER(ttl)); 284 } 285 286 /*-------------------------------------------------------------------------*/ 287 288 static int net1080_reset(struct usbnet *dev) 289 { 290 u16 usbctl, status, ttl; 291 u16 *vp = kmalloc(sizeof (u16), GFP_KERNEL); 292 int retval; 293 294 if (!vp) 295 return -ENOMEM; 296 297 // nc_dump_registers(dev); 298 299 if ((retval = nc_register_read(dev, REG_STATUS, vp)) < 0) { 300 netdev_dbg(dev->net, "can't read %s-%s status: %d\n", 301 dev->udev->bus->bus_name, dev->udev->devpath, retval); 302 goto done; 303 } 304 status = *vp; 305 nc_dump_status(dev, status); 306 307 if ((retval = nc_register_read(dev, REG_USBCTL, vp)) < 0) { 308 netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval); 309 goto done; 310 } 311 usbctl = *vp; 312 nc_dump_usbctl(dev, usbctl); 313 314 nc_register_write(dev, REG_USBCTL, 315 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER); 316 317 if ((retval = nc_register_read(dev, REG_TTL, vp)) < 0) { 318 netdev_dbg(dev->net, "can't read TTL, %d\n", retval); 319 goto done; 320 } 321 ttl = *vp; 322 // nc_dump_ttl(dev, ttl); 323 324 nc_register_write(dev, REG_TTL, 325 MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) ); 326 netdev_dbg(dev->net, "assigned TTL, %d ms\n", NC_READ_TTL_MS); 327 328 netif_info(dev, link, dev->net, "port %c, peer %sconnected\n", 329 (status & STATUS_PORT_A) ? 'A' : 'B', 330 (status & STATUS_CONN_OTHER) ? "" : "dis"); 331 retval = 0; 332 333 done: 334 kfree(vp); 335 return retval; 336 } 337 338 static int net1080_check_connect(struct usbnet *dev) 339 { 340 int retval; 341 u16 status; 342 u16 *vp = kmalloc(sizeof (u16), GFP_KERNEL); 343 344 if (!vp) 345 return -ENOMEM; 346 retval = nc_register_read(dev, REG_STATUS, vp); 347 status = *vp; 348 kfree(vp); 349 if (retval != 0) { 350 netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval); 351 return retval; 352 } 353 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER) 354 return -ENOLINK; 355 return 0; 356 } 357 358 static void nc_flush_complete(struct urb *urb) 359 { 360 kfree(urb->context); 361 usb_free_urb(urb); 362 } 363 364 static void nc_ensure_sync(struct usbnet *dev) 365 { 366 dev->frame_errors++; 367 if (dev->frame_errors > 5) { 368 struct urb *urb; 369 struct usb_ctrlrequest *req; 370 int status; 371 372 /* Send a flush */ 373 urb = usb_alloc_urb(0, GFP_ATOMIC); 374 if (!urb) 375 return; 376 377 req = kmalloc(sizeof *req, GFP_ATOMIC); 378 if (!req) { 379 usb_free_urb(urb); 380 return; 381 } 382 383 req->bRequestType = USB_DIR_OUT 384 | USB_TYPE_VENDOR 385 | USB_RECIP_DEVICE; 386 req->bRequest = REQUEST_REGISTER; 387 req->wValue = cpu_to_le16(USBCTL_FLUSH_THIS 388 | USBCTL_FLUSH_OTHER); 389 req->wIndex = cpu_to_le16(REG_USBCTL); 390 req->wLength = cpu_to_le16(0); 391 392 /* queue an async control request, we don't need 393 * to do anything when it finishes except clean up. 394 */ 395 usb_fill_control_urb(urb, dev->udev, 396 usb_sndctrlpipe(dev->udev, 0), 397 (unsigned char *) req, 398 NULL, 0, 399 nc_flush_complete, req); 400 status = usb_submit_urb(urb, GFP_ATOMIC); 401 if (status) { 402 kfree(req); 403 usb_free_urb(urb); 404 return; 405 } 406 407 netif_dbg(dev, rx_err, dev->net, 408 "flush net1080; too many framing errors\n"); 409 dev->frame_errors = 0; 410 } 411 } 412 413 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 414 { 415 struct nc_header *header; 416 struct nc_trailer *trailer; 417 u16 hdr_len, packet_len; 418 419 if (!(skb->len & 0x01)) { 420 netdev_dbg(dev->net, "rx framesize %d range %d..%d mtu %d\n", 421 skb->len, dev->net->hard_header_len, dev->hard_mtu, 422 dev->net->mtu); 423 dev->net->stats.rx_frame_errors++; 424 nc_ensure_sync(dev); 425 return 0; 426 } 427 428 header = (struct nc_header *) skb->data; 429 hdr_len = le16_to_cpup(&header->hdr_len); 430 packet_len = le16_to_cpup(&header->packet_len); 431 if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) { 432 dev->net->stats.rx_frame_errors++; 433 netdev_dbg(dev->net, "packet too big, %d\n", packet_len); 434 nc_ensure_sync(dev); 435 return 0; 436 } else if (hdr_len < MIN_HEADER) { 437 dev->net->stats.rx_frame_errors++; 438 netdev_dbg(dev->net, "header too short, %d\n", hdr_len); 439 nc_ensure_sync(dev); 440 return 0; 441 } else if (hdr_len > MIN_HEADER) { 442 // out of band data for us? 443 netdev_dbg(dev->net, "header OOB, %d bytes\n", hdr_len - MIN_HEADER); 444 nc_ensure_sync(dev); 445 // switch (vendor/product ids) { ... } 446 } 447 skb_pull(skb, hdr_len); 448 449 trailer = (struct nc_trailer *) 450 (skb->data + skb->len - sizeof *trailer); 451 skb_trim(skb, skb->len - sizeof *trailer); 452 453 if ((packet_len & 0x01) == 0) { 454 if (skb->data [packet_len] != PAD_BYTE) { 455 dev->net->stats.rx_frame_errors++; 456 netdev_dbg(dev->net, "bad pad\n"); 457 return 0; 458 } 459 skb_trim(skb, skb->len - 1); 460 } 461 if (skb->len != packet_len) { 462 dev->net->stats.rx_frame_errors++; 463 netdev_dbg(dev->net, "bad packet len %d (expected %d)\n", 464 skb->len, packet_len); 465 nc_ensure_sync(dev); 466 return 0; 467 } 468 if (header->packet_id != get_unaligned(&trailer->packet_id)) { 469 dev->net->stats.rx_fifo_errors++; 470 netdev_dbg(dev->net, "(2+ dropped) rx packet_id mismatch 0x%x 0x%x\n", 471 le16_to_cpu(header->packet_id), 472 le16_to_cpu(trailer->packet_id)); 473 return 0; 474 } 475 #if 0 476 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len, 477 header->packet_len, header->packet_id); 478 #endif 479 dev->frame_errors = 0; 480 return 1; 481 } 482 483 static struct sk_buff * 484 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 485 { 486 struct sk_buff *skb2; 487 struct nc_header *header = NULL; 488 struct nc_trailer *trailer = NULL; 489 int padlen = sizeof (struct nc_trailer); 490 int len = skb->len; 491 492 if (!((len + padlen + sizeof (struct nc_header)) & 0x01)) 493 padlen++; 494 if (!skb_cloned(skb)) { 495 int headroom = skb_headroom(skb); 496 int tailroom = skb_tailroom(skb); 497 498 if (padlen <= tailroom && 499 sizeof(struct nc_header) <= headroom) 500 /* There's enough head and tail room */ 501 goto encapsulate; 502 503 if ((sizeof (struct nc_header) + padlen) < 504 (headroom + tailroom)) { 505 /* There's enough total room, so just readjust */ 506 skb->data = memmove(skb->head 507 + sizeof (struct nc_header), 508 skb->data, skb->len); 509 skb_set_tail_pointer(skb, len); 510 goto encapsulate; 511 } 512 } 513 514 /* Create a new skb to use with the correct size */ 515 skb2 = skb_copy_expand(skb, 516 sizeof (struct nc_header), 517 padlen, 518 flags); 519 dev_kfree_skb_any(skb); 520 if (!skb2) 521 return skb2; 522 skb = skb2; 523 524 encapsulate: 525 /* header first */ 526 header = (struct nc_header *) skb_push(skb, sizeof *header); 527 header->hdr_len = cpu_to_le16(sizeof (*header)); 528 header->packet_len = cpu_to_le16(len); 529 header->packet_id = cpu_to_le16((u16)dev->xid++); 530 531 /* maybe pad; then trailer */ 532 if (!((skb->len + sizeof *trailer) & 0x01)) 533 *skb_put(skb, 1) = PAD_BYTE; 534 trailer = (struct nc_trailer *) skb_put(skb, sizeof *trailer); 535 put_unaligned(header->packet_id, &trailer->packet_id); 536 #if 0 537 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n", 538 header->hdr_len, header->packet_len, 539 header->packet_id); 540 #endif 541 return skb; 542 } 543 544 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf) 545 { 546 unsigned extra = sizeof (struct nc_header) 547 + 1 548 + sizeof (struct nc_trailer); 549 550 dev->net->hard_header_len += extra; 551 dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu; 552 dev->hard_mtu = NC_MAX_PACKET; 553 return usbnet_get_endpoints (dev, intf); 554 } 555 556 static const struct driver_info net1080_info = { 557 .description = "NetChip TurboCONNECT", 558 .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_NC, 559 .bind = net1080_bind, 560 .reset = net1080_reset, 561 .check_connect = net1080_check_connect, 562 .rx_fixup = net1080_rx_fixup, 563 .tx_fixup = net1080_tx_fixup, 564 }; 565 566 static const struct usb_device_id products [] = { 567 { 568 USB_DEVICE(0x0525, 0x1080), // NetChip ref design 569 .driver_info = (unsigned long) &net1080_info, 570 }, { 571 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold 572 .driver_info = (unsigned long) &net1080_info, 573 }, 574 { }, // END 575 }; 576 MODULE_DEVICE_TABLE(usb, products); 577 578 static struct usb_driver net1080_driver = { 579 .name = "net1080", 580 .id_table = products, 581 .probe = usbnet_probe, 582 .disconnect = usbnet_disconnect, 583 .suspend = usbnet_suspend, 584 .resume = usbnet_resume, 585 .disable_hub_initiated_lpm = 1, 586 }; 587 588 module_usb_driver(net1080_driver); 589 590 MODULE_AUTHOR("David Brownell"); 591 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links"); 592 MODULE_LICENSE("GPL"); 593