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, see <http://www.gnu.org/licenses/>. 17 */ 18 19 // #define DEBUG // error path messages, extra info 20 // #define VERBOSE // more; success messages 21 22 #include <linux/module.h> 23 #include <linux/netdevice.h> 24 #include <linux/etherdevice.h> 25 #include <linux/ethtool.h> 26 #include <linux/workqueue.h> 27 #include <linux/mii.h> 28 #include <linux/usb.h> 29 #include <linux/usb/usbnet.h> 30 #include <linux/slab.h> 31 32 #include <asm/unaligned.h> 33 34 35 /* 36 * Netchip 1080 driver ... http://www.netchip.com 37 * (Sept 2004: End-of-life announcement has been sent.) 38 * Used in (some) LapLink cables 39 */ 40 41 #define frame_errors data[1] 42 43 /* 44 * NetChip framing of ethernet packets, supporting additional error 45 * checks for links that may drop bulk packets from inside messages. 46 * Odd USB length == always short read for last usb packet. 47 * - nc_header 48 * - Ethernet header (14 bytes) 49 * - payload 50 * - (optional padding byte, if needed so length becomes odd) 51 * - nc_trailer 52 * 53 * This framing is to be avoided for non-NetChip devices. 54 */ 55 56 struct nc_header { // packed: 57 __le16 hdr_len; // sizeof nc_header (LE, all) 58 __le16 packet_len; // payload size (including ethhdr) 59 __le16 packet_id; // detects dropped packets 60 #define MIN_HEADER 6 61 62 // all else is optional, and must start with: 63 // __le16 vendorId; // from usb-if 64 // __le16 productId; 65 } __packed; 66 67 #define PAD_BYTE ((unsigned char)0xAC) 68 69 struct nc_trailer { 70 __le16 packet_id; 71 } __packed; 72 73 // packets may use FLAG_FRAMING_NC and optional pad 74 #define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \ 75 + sizeof (struct ethhdr) \ 76 + (mtu) \ 77 + 1 \ 78 + sizeof (struct nc_trailer)) 79 80 #define MIN_FRAMED FRAMED_SIZE(0) 81 82 /* packets _could_ be up to 64KB... */ 83 #define NC_MAX_PACKET 32767 84 85 86 /* 87 * Zero means no timeout; else, how long a 64 byte bulk packet may be queued 88 * before the hardware drops it. If that's done, the driver will need to 89 * frame network packets to guard against the dropped USB packets. The win32 90 * driver sets this for both sides of the link. 91 */ 92 #define NC_READ_TTL_MS ((u8)255) // ms 93 94 /* 95 * We ignore most registers and EEPROM contents. 96 */ 97 #define REG_USBCTL ((u8)0x04) 98 #define REG_TTL ((u8)0x10) 99 #define REG_STATUS ((u8)0x11) 100 101 /* 102 * Vendor specific requests to read/write data 103 */ 104 #define REQUEST_REGISTER ((u8)0x10) 105 #define REQUEST_EEPROM ((u8)0x11) 106 107 static int 108 nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr) 109 { 110 int status = usbnet_read_cmd(dev, req, 111 USB_DIR_IN | USB_TYPE_VENDOR | 112 USB_RECIP_DEVICE, 113 0, regnum, retval_ptr, 114 sizeof *retval_ptr); 115 if (status > 0) 116 status = 0; 117 if (!status) 118 le16_to_cpus(retval_ptr); 119 return status; 120 } 121 122 static inline int 123 nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr) 124 { 125 return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr); 126 } 127 128 // no retval ... can become async, usable in_interrupt() 129 static void 130 nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value) 131 { 132 usbnet_write_cmd(dev, req, 133 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 134 value, regnum, NULL, 0); 135 } 136 137 static inline void 138 nc_register_write(struct usbnet *dev, u8 regnum, u16 value) 139 { 140 nc_vendor_write(dev, REQUEST_REGISTER, regnum, value); 141 } 142 143 144 #if 0 145 static void nc_dump_registers(struct usbnet *dev) 146 { 147 u8 reg; 148 u16 *vp = kmalloc(sizeof (u16)); 149 150 if (!vp) 151 return; 152 153 netdev_dbg(dev->net, "registers:\n"); 154 for (reg = 0; reg < 0x20; reg++) { 155 int retval; 156 157 // reading some registers is trouble 158 if (reg >= 0x08 && reg <= 0xf) 159 continue; 160 if (reg >= 0x12 && reg <= 0x1e) 161 continue; 162 163 retval = nc_register_read(dev, reg, vp); 164 if (retval < 0) 165 netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n", 166 reg, retval); 167 else 168 netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp); 169 } 170 kfree(vp); 171 } 172 #endif 173 174 175 /*-------------------------------------------------------------------------*/ 176 177 /* 178 * Control register 179 */ 180 181 #define USBCTL_WRITABLE_MASK 0x1f0f 182 // bits 15-13 reserved, r/o 183 #define USBCTL_ENABLE_LANG (1 << 12) 184 #define USBCTL_ENABLE_MFGR (1 << 11) 185 #define USBCTL_ENABLE_PROD (1 << 10) 186 #define USBCTL_ENABLE_SERIAL (1 << 9) 187 #define USBCTL_ENABLE_DEFAULTS (1 << 8) 188 // bits 7-4 reserved, r/o 189 #define USBCTL_FLUSH_OTHER (1 << 3) 190 #define USBCTL_FLUSH_THIS (1 << 2) 191 #define USBCTL_DISCONN_OTHER (1 << 1) 192 #define USBCTL_DISCONN_THIS (1 << 0) 193 194 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl) 195 { 196 netif_dbg(dev, link, dev->net, 197 "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n", 198 dev->udev->bus->bus_name, dev->udev->devpath, 199 usbctl, 200 (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "", 201 (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "", 202 (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "", 203 (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "", 204 (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "", 205 206 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "", 207 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "", 208 209 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "", 210 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "", 211 212 usbctl & ~USBCTL_WRITABLE_MASK); 213 } 214 215 /*-------------------------------------------------------------------------*/ 216 217 /* 218 * Status register 219 */ 220 221 #define STATUS_PORT_A (1 << 15) 222 223 #define STATUS_CONN_OTHER (1 << 14) 224 #define STATUS_SUSPEND_OTHER (1 << 13) 225 #define STATUS_MAILBOX_OTHER (1 << 12) 226 #define STATUS_PACKETS_OTHER(n) (((n) >> 8) & 0x03) 227 228 #define STATUS_CONN_THIS (1 << 6) 229 #define STATUS_SUSPEND_THIS (1 << 5) 230 #define STATUS_MAILBOX_THIS (1 << 4) 231 #define STATUS_PACKETS_THIS(n) (((n) >> 0) & 0x03) 232 233 #define STATUS_UNSPEC_MASK 0x0c8c 234 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK)) 235 236 237 static inline void nc_dump_status(struct usbnet *dev, u16 status) 238 { 239 netif_dbg(dev, link, dev->net, 240 "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n", 241 dev->udev->bus->bus_name, dev->udev->devpath, 242 status, 243 244 // XXX the packet counts don't seem right 245 // (1 at reset, not 0); maybe UNSPEC too 246 247 (status & STATUS_PORT_A) ? 'A' : 'B', 248 STATUS_PACKETS_THIS(status), 249 (status & STATUS_CONN_THIS) ? " CON" : "", 250 (status & STATUS_SUSPEND_THIS) ? " SUS" : "", 251 (status & STATUS_MAILBOX_THIS) ? " MBOX" : "", 252 253 STATUS_PACKETS_OTHER(status), 254 (status & STATUS_CONN_OTHER) ? " CON" : "", 255 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "", 256 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "", 257 258 status & STATUS_UNSPEC_MASK); 259 } 260 261 /*-------------------------------------------------------------------------*/ 262 263 /* 264 * TTL register 265 */ 266 267 #define TTL_THIS(ttl) (0x00ff & ttl) 268 #define TTL_OTHER(ttl) (0x00ff & (ttl >> 8)) 269 #define MK_TTL(this,other) ((u16)(((other)<<8)|(0x00ff&(this)))) 270 271 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl) 272 { 273 netif_dbg(dev, link, dev->net, "net1080 %s-%s ttl 0x%x this = %d, other = %d\n", 274 dev->udev->bus->bus_name, dev->udev->devpath, 275 ttl, TTL_THIS(ttl), TTL_OTHER(ttl)); 276 } 277 278 /*-------------------------------------------------------------------------*/ 279 280 static int net1080_reset(struct usbnet *dev) 281 { 282 u16 usbctl, status, ttl; 283 u16 vp; 284 int retval; 285 286 // nc_dump_registers(dev); 287 288 if ((retval = nc_register_read(dev, REG_STATUS, &vp)) < 0) { 289 netdev_dbg(dev->net, "can't read %s-%s status: %d\n", 290 dev->udev->bus->bus_name, dev->udev->devpath, retval); 291 goto done; 292 } 293 status = vp; 294 nc_dump_status(dev, status); 295 296 if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) { 297 netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval); 298 goto done; 299 } 300 usbctl = vp; 301 nc_dump_usbctl(dev, usbctl); 302 303 nc_register_write(dev, REG_USBCTL, 304 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER); 305 306 if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) { 307 netdev_dbg(dev->net, "can't read TTL, %d\n", retval); 308 goto done; 309 } 310 ttl = vp; 311 // nc_dump_ttl(dev, ttl); 312 313 nc_register_write(dev, REG_TTL, 314 MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) ); 315 netdev_dbg(dev->net, "assigned TTL, %d ms\n", NC_READ_TTL_MS); 316 317 netif_info(dev, link, dev->net, "port %c, peer %sconnected\n", 318 (status & STATUS_PORT_A) ? 'A' : 'B', 319 (status & STATUS_CONN_OTHER) ? "" : "dis"); 320 retval = 0; 321 322 done: 323 return retval; 324 } 325 326 static int net1080_check_connect(struct usbnet *dev) 327 { 328 int retval; 329 u16 status; 330 u16 vp; 331 332 retval = nc_register_read(dev, REG_STATUS, &vp); 333 status = vp; 334 if (retval != 0) { 335 netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval); 336 return retval; 337 } 338 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER) 339 return -ENOLINK; 340 return 0; 341 } 342 343 static void nc_ensure_sync(struct usbnet *dev) 344 { 345 if (++dev->frame_errors <= 5) 346 return; 347 348 if (usbnet_write_cmd_async(dev, REQUEST_REGISTER, 349 USB_DIR_OUT | USB_TYPE_VENDOR | 350 USB_RECIP_DEVICE, 351 USBCTL_FLUSH_THIS | 352 USBCTL_FLUSH_OTHER, 353 REG_USBCTL, NULL, 0)) 354 return; 355 356 netif_dbg(dev, rx_err, dev->net, 357 "flush net1080; too many framing errors\n"); 358 dev->frame_errors = 0; 359 } 360 361 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 362 { 363 struct nc_header *header; 364 struct nc_trailer *trailer; 365 u16 hdr_len, packet_len; 366 367 /* This check is no longer done by usbnet */ 368 if (skb->len < dev->net->hard_header_len) 369 return 0; 370 371 if (!(skb->len & 0x01)) { 372 netdev_dbg(dev->net, "rx framesize %d range %d..%d mtu %d\n", 373 skb->len, dev->net->hard_header_len, dev->hard_mtu, 374 dev->net->mtu); 375 dev->net->stats.rx_frame_errors++; 376 nc_ensure_sync(dev); 377 return 0; 378 } 379 380 header = (struct nc_header *) skb->data; 381 hdr_len = le16_to_cpup(&header->hdr_len); 382 packet_len = le16_to_cpup(&header->packet_len); 383 if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) { 384 dev->net->stats.rx_frame_errors++; 385 netdev_dbg(dev->net, "packet too big, %d\n", packet_len); 386 nc_ensure_sync(dev); 387 return 0; 388 } else if (hdr_len < MIN_HEADER) { 389 dev->net->stats.rx_frame_errors++; 390 netdev_dbg(dev->net, "header too short, %d\n", hdr_len); 391 nc_ensure_sync(dev); 392 return 0; 393 } else if (hdr_len > MIN_HEADER) { 394 // out of band data for us? 395 netdev_dbg(dev->net, "header OOB, %d bytes\n", hdr_len - MIN_HEADER); 396 nc_ensure_sync(dev); 397 // switch (vendor/product ids) { ... } 398 } 399 skb_pull(skb, hdr_len); 400 401 trailer = (struct nc_trailer *) 402 (skb->data + skb->len - sizeof *trailer); 403 skb_trim(skb, skb->len - sizeof *trailer); 404 405 if ((packet_len & 0x01) == 0) { 406 if (skb->data [packet_len] != PAD_BYTE) { 407 dev->net->stats.rx_frame_errors++; 408 netdev_dbg(dev->net, "bad pad\n"); 409 return 0; 410 } 411 skb_trim(skb, skb->len - 1); 412 } 413 if (skb->len != packet_len) { 414 dev->net->stats.rx_frame_errors++; 415 netdev_dbg(dev->net, "bad packet len %d (expected %d)\n", 416 skb->len, packet_len); 417 nc_ensure_sync(dev); 418 return 0; 419 } 420 if (header->packet_id != get_unaligned(&trailer->packet_id)) { 421 dev->net->stats.rx_fifo_errors++; 422 netdev_dbg(dev->net, "(2+ dropped) rx packet_id mismatch 0x%x 0x%x\n", 423 le16_to_cpu(header->packet_id), 424 le16_to_cpu(trailer->packet_id)); 425 return 0; 426 } 427 #if 0 428 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len, 429 header->packet_len, header->packet_id); 430 #endif 431 dev->frame_errors = 0; 432 return 1; 433 } 434 435 static struct sk_buff * 436 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 437 { 438 struct sk_buff *skb2; 439 struct nc_header *header = NULL; 440 struct nc_trailer *trailer = NULL; 441 int padlen = sizeof (struct nc_trailer); 442 int len = skb->len; 443 444 if (!((len + padlen + sizeof (struct nc_header)) & 0x01)) 445 padlen++; 446 if (!skb_cloned(skb)) { 447 int headroom = skb_headroom(skb); 448 int tailroom = skb_tailroom(skb); 449 450 if (padlen <= tailroom && 451 sizeof(struct nc_header) <= headroom) 452 /* There's enough head and tail room */ 453 goto encapsulate; 454 455 if ((sizeof (struct nc_header) + padlen) < 456 (headroom + tailroom)) { 457 /* There's enough total room, so just readjust */ 458 skb->data = memmove(skb->head 459 + sizeof (struct nc_header), 460 skb->data, skb->len); 461 skb_set_tail_pointer(skb, len); 462 goto encapsulate; 463 } 464 } 465 466 /* Create a new skb to use with the correct size */ 467 skb2 = skb_copy_expand(skb, 468 sizeof (struct nc_header), 469 padlen, 470 flags); 471 dev_kfree_skb_any(skb); 472 if (!skb2) 473 return skb2; 474 skb = skb2; 475 476 encapsulate: 477 /* header first */ 478 header = (struct nc_header *) skb_push(skb, sizeof *header); 479 header->hdr_len = cpu_to_le16(sizeof (*header)); 480 header->packet_len = cpu_to_le16(len); 481 header->packet_id = cpu_to_le16((u16)dev->xid++); 482 483 /* maybe pad; then trailer */ 484 if (!((skb->len + sizeof *trailer) & 0x01)) 485 *skb_put(skb, 1) = PAD_BYTE; 486 trailer = (struct nc_trailer *) skb_put(skb, sizeof *trailer); 487 put_unaligned(header->packet_id, &trailer->packet_id); 488 #if 0 489 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n", 490 header->hdr_len, header->packet_len, 491 header->packet_id); 492 #endif 493 return skb; 494 } 495 496 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf) 497 { 498 unsigned extra = sizeof (struct nc_header) 499 + 1 500 + sizeof (struct nc_trailer); 501 502 dev->net->hard_header_len += extra; 503 dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu; 504 dev->hard_mtu = NC_MAX_PACKET; 505 return usbnet_get_endpoints (dev, intf); 506 } 507 508 static const struct driver_info net1080_info = { 509 .description = "NetChip TurboCONNECT", 510 .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_NC, 511 .bind = net1080_bind, 512 .reset = net1080_reset, 513 .check_connect = net1080_check_connect, 514 .rx_fixup = net1080_rx_fixup, 515 .tx_fixup = net1080_tx_fixup, 516 }; 517 518 static const struct usb_device_id products [] = { 519 { 520 USB_DEVICE(0x0525, 0x1080), // NetChip ref design 521 .driver_info = (unsigned long) &net1080_info, 522 }, { 523 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold 524 .driver_info = (unsigned long) &net1080_info, 525 }, 526 { }, // END 527 }; 528 MODULE_DEVICE_TABLE(usb, products); 529 530 static struct usb_driver net1080_driver = { 531 .name = "net1080", 532 .id_table = products, 533 .probe = usbnet_probe, 534 .disconnect = usbnet_disconnect, 535 .suspend = usbnet_suspend, 536 .resume = usbnet_resume, 537 .disable_hub_initiated_lpm = 1, 538 }; 539 540 module_usb_driver(net1080_driver); 541 542 MODULE_AUTHOR("David Brownell"); 543 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links"); 544 MODULE_LICENSE("GPL"); 545