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 = usbnet_read_cmd(dev, req, 113 USB_DIR_IN | USB_TYPE_VENDOR | 114 USB_RECIP_DEVICE, 115 0, regnum, retval_ptr, 116 sizeof *retval_ptr); 117 if (status > 0) 118 status = 0; 119 if (!status) 120 le16_to_cpus(retval_ptr); 121 return status; 122 } 123 124 static inline int 125 nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr) 126 { 127 return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr); 128 } 129 130 // no retval ... can become async, usable in_interrupt() 131 static void 132 nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value) 133 { 134 usbnet_write_cmd(dev, req, 135 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE, 136 value, regnum, NULL, 0); 137 } 138 139 static inline void 140 nc_register_write(struct usbnet *dev, u8 regnum, u16 value) 141 { 142 nc_vendor_write(dev, REQUEST_REGISTER, regnum, value); 143 } 144 145 146 #if 0 147 static void nc_dump_registers(struct usbnet *dev) 148 { 149 u8 reg; 150 u16 *vp = kmalloc(sizeof (u16)); 151 152 if (!vp) 153 return; 154 155 netdev_dbg(dev->net, "registers:\n"); 156 for (reg = 0; reg < 0x20; reg++) { 157 int retval; 158 159 // reading some registers is trouble 160 if (reg >= 0x08 && reg <= 0xf) 161 continue; 162 if (reg >= 0x12 && reg <= 0x1e) 163 continue; 164 165 retval = nc_register_read(dev, reg, vp); 166 if (retval < 0) 167 netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n", 168 reg, retval); 169 else 170 netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp); 171 } 172 kfree(vp); 173 } 174 #endif 175 176 177 /*-------------------------------------------------------------------------*/ 178 179 /* 180 * Control register 181 */ 182 183 #define USBCTL_WRITABLE_MASK 0x1f0f 184 // bits 15-13 reserved, r/o 185 #define USBCTL_ENABLE_LANG (1 << 12) 186 #define USBCTL_ENABLE_MFGR (1 << 11) 187 #define USBCTL_ENABLE_PROD (1 << 10) 188 #define USBCTL_ENABLE_SERIAL (1 << 9) 189 #define USBCTL_ENABLE_DEFAULTS (1 << 8) 190 // bits 7-4 reserved, r/o 191 #define USBCTL_FLUSH_OTHER (1 << 3) 192 #define USBCTL_FLUSH_THIS (1 << 2) 193 #define USBCTL_DISCONN_OTHER (1 << 1) 194 #define USBCTL_DISCONN_THIS (1 << 0) 195 196 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl) 197 { 198 netif_dbg(dev, link, dev->net, 199 "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n", 200 dev->udev->bus->bus_name, dev->udev->devpath, 201 usbctl, 202 (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "", 203 (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "", 204 (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "", 205 (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "", 206 (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "", 207 208 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "", 209 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "", 210 211 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "", 212 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "", 213 214 usbctl & ~USBCTL_WRITABLE_MASK); 215 } 216 217 /*-------------------------------------------------------------------------*/ 218 219 /* 220 * Status register 221 */ 222 223 #define STATUS_PORT_A (1 << 15) 224 225 #define STATUS_CONN_OTHER (1 << 14) 226 #define STATUS_SUSPEND_OTHER (1 << 13) 227 #define STATUS_MAILBOX_OTHER (1 << 12) 228 #define STATUS_PACKETS_OTHER(n) (((n) >> 8) & 0x03) 229 230 #define STATUS_CONN_THIS (1 << 6) 231 #define STATUS_SUSPEND_THIS (1 << 5) 232 #define STATUS_MAILBOX_THIS (1 << 4) 233 #define STATUS_PACKETS_THIS(n) (((n) >> 0) & 0x03) 234 235 #define STATUS_UNSPEC_MASK 0x0c8c 236 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK)) 237 238 239 static inline void nc_dump_status(struct usbnet *dev, u16 status) 240 { 241 netif_dbg(dev, link, dev->net, 242 "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n", 243 dev->udev->bus->bus_name, dev->udev->devpath, 244 status, 245 246 // XXX the packet counts don't seem right 247 // (1 at reset, not 0); maybe UNSPEC too 248 249 (status & STATUS_PORT_A) ? 'A' : 'B', 250 STATUS_PACKETS_THIS(status), 251 (status & STATUS_CONN_THIS) ? " CON" : "", 252 (status & STATUS_SUSPEND_THIS) ? " SUS" : "", 253 (status & STATUS_MAILBOX_THIS) ? " MBOX" : "", 254 255 STATUS_PACKETS_OTHER(status), 256 (status & STATUS_CONN_OTHER) ? " CON" : "", 257 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "", 258 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "", 259 260 status & STATUS_UNSPEC_MASK); 261 } 262 263 /*-------------------------------------------------------------------------*/ 264 265 /* 266 * TTL register 267 */ 268 269 #define TTL_THIS(ttl) (0x00ff & ttl) 270 #define TTL_OTHER(ttl) (0x00ff & (ttl >> 8)) 271 #define MK_TTL(this,other) ((u16)(((other)<<8)|(0x00ff&(this)))) 272 273 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl) 274 { 275 netif_dbg(dev, link, dev->net, "net1080 %s-%s ttl 0x%x this = %d, other = %d\n", 276 dev->udev->bus->bus_name, dev->udev->devpath, 277 ttl, TTL_THIS(ttl), TTL_OTHER(ttl)); 278 } 279 280 /*-------------------------------------------------------------------------*/ 281 282 static int net1080_reset(struct usbnet *dev) 283 { 284 u16 usbctl, status, ttl; 285 u16 vp; 286 int retval; 287 288 // nc_dump_registers(dev); 289 290 if ((retval = nc_register_read(dev, REG_STATUS, &vp)) < 0) { 291 netdev_dbg(dev->net, "can't read %s-%s status: %d\n", 292 dev->udev->bus->bus_name, dev->udev->devpath, retval); 293 goto done; 294 } 295 status = vp; 296 nc_dump_status(dev, status); 297 298 if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) { 299 netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval); 300 goto done; 301 } 302 usbctl = vp; 303 nc_dump_usbctl(dev, usbctl); 304 305 nc_register_write(dev, REG_USBCTL, 306 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER); 307 308 if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) { 309 netdev_dbg(dev->net, "can't read TTL, %d\n", retval); 310 goto done; 311 } 312 ttl = vp; 313 // nc_dump_ttl(dev, ttl); 314 315 nc_register_write(dev, REG_TTL, 316 MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) ); 317 netdev_dbg(dev->net, "assigned TTL, %d ms\n", NC_READ_TTL_MS); 318 319 netif_info(dev, link, dev->net, "port %c, peer %sconnected\n", 320 (status & STATUS_PORT_A) ? 'A' : 'B', 321 (status & STATUS_CONN_OTHER) ? "" : "dis"); 322 retval = 0; 323 324 done: 325 return retval; 326 } 327 328 static int net1080_check_connect(struct usbnet *dev) 329 { 330 int retval; 331 u16 status; 332 u16 vp; 333 334 retval = nc_register_read(dev, REG_STATUS, &vp); 335 status = vp; 336 if (retval != 0) { 337 netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval); 338 return retval; 339 } 340 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER) 341 return -ENOLINK; 342 return 0; 343 } 344 345 static void nc_ensure_sync(struct usbnet *dev) 346 { 347 if (++dev->frame_errors <= 5) 348 return; 349 350 if (usbnet_write_cmd_async(dev, REQUEST_REGISTER, 351 USB_DIR_OUT | USB_TYPE_VENDOR | 352 USB_RECIP_DEVICE, 353 USBCTL_FLUSH_THIS | 354 USBCTL_FLUSH_OTHER, 355 REG_USBCTL, NULL, 0)) 356 return; 357 358 netif_dbg(dev, rx_err, dev->net, 359 "flush net1080; too many framing errors\n"); 360 dev->frame_errors = 0; 361 } 362 363 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb) 364 { 365 struct nc_header *header; 366 struct nc_trailer *trailer; 367 u16 hdr_len, packet_len; 368 369 if (!(skb->len & 0x01)) { 370 netdev_dbg(dev->net, "rx framesize %d range %d..%d mtu %d\n", 371 skb->len, dev->net->hard_header_len, dev->hard_mtu, 372 dev->net->mtu); 373 dev->net->stats.rx_frame_errors++; 374 nc_ensure_sync(dev); 375 return 0; 376 } 377 378 header = (struct nc_header *) skb->data; 379 hdr_len = le16_to_cpup(&header->hdr_len); 380 packet_len = le16_to_cpup(&header->packet_len); 381 if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) { 382 dev->net->stats.rx_frame_errors++; 383 netdev_dbg(dev->net, "packet too big, %d\n", packet_len); 384 nc_ensure_sync(dev); 385 return 0; 386 } else if (hdr_len < MIN_HEADER) { 387 dev->net->stats.rx_frame_errors++; 388 netdev_dbg(dev->net, "header too short, %d\n", hdr_len); 389 nc_ensure_sync(dev); 390 return 0; 391 } else if (hdr_len > MIN_HEADER) { 392 // out of band data for us? 393 netdev_dbg(dev->net, "header OOB, %d bytes\n", hdr_len - MIN_HEADER); 394 nc_ensure_sync(dev); 395 // switch (vendor/product ids) { ... } 396 } 397 skb_pull(skb, hdr_len); 398 399 trailer = (struct nc_trailer *) 400 (skb->data + skb->len - sizeof *trailer); 401 skb_trim(skb, skb->len - sizeof *trailer); 402 403 if ((packet_len & 0x01) == 0) { 404 if (skb->data [packet_len] != PAD_BYTE) { 405 dev->net->stats.rx_frame_errors++; 406 netdev_dbg(dev->net, "bad pad\n"); 407 return 0; 408 } 409 skb_trim(skb, skb->len - 1); 410 } 411 if (skb->len != packet_len) { 412 dev->net->stats.rx_frame_errors++; 413 netdev_dbg(dev->net, "bad packet len %d (expected %d)\n", 414 skb->len, packet_len); 415 nc_ensure_sync(dev); 416 return 0; 417 } 418 if (header->packet_id != get_unaligned(&trailer->packet_id)) { 419 dev->net->stats.rx_fifo_errors++; 420 netdev_dbg(dev->net, "(2+ dropped) rx packet_id mismatch 0x%x 0x%x\n", 421 le16_to_cpu(header->packet_id), 422 le16_to_cpu(trailer->packet_id)); 423 return 0; 424 } 425 #if 0 426 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len, 427 header->packet_len, header->packet_id); 428 #endif 429 dev->frame_errors = 0; 430 return 1; 431 } 432 433 static struct sk_buff * 434 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) 435 { 436 struct sk_buff *skb2; 437 struct nc_header *header = NULL; 438 struct nc_trailer *trailer = NULL; 439 int padlen = sizeof (struct nc_trailer); 440 int len = skb->len; 441 442 if (!((len + padlen + sizeof (struct nc_header)) & 0x01)) 443 padlen++; 444 if (!skb_cloned(skb)) { 445 int headroom = skb_headroom(skb); 446 int tailroom = skb_tailroom(skb); 447 448 if (padlen <= tailroom && 449 sizeof(struct nc_header) <= headroom) 450 /* There's enough head and tail room */ 451 goto encapsulate; 452 453 if ((sizeof (struct nc_header) + padlen) < 454 (headroom + tailroom)) { 455 /* There's enough total room, so just readjust */ 456 skb->data = memmove(skb->head 457 + sizeof (struct nc_header), 458 skb->data, skb->len); 459 skb_set_tail_pointer(skb, len); 460 goto encapsulate; 461 } 462 } 463 464 /* Create a new skb to use with the correct size */ 465 skb2 = skb_copy_expand(skb, 466 sizeof (struct nc_header), 467 padlen, 468 flags); 469 dev_kfree_skb_any(skb); 470 if (!skb2) 471 return skb2; 472 skb = skb2; 473 474 encapsulate: 475 /* header first */ 476 header = (struct nc_header *) skb_push(skb, sizeof *header); 477 header->hdr_len = cpu_to_le16(sizeof (*header)); 478 header->packet_len = cpu_to_le16(len); 479 header->packet_id = cpu_to_le16((u16)dev->xid++); 480 481 /* maybe pad; then trailer */ 482 if (!((skb->len + sizeof *trailer) & 0x01)) 483 *skb_put(skb, 1) = PAD_BYTE; 484 trailer = (struct nc_trailer *) skb_put(skb, sizeof *trailer); 485 put_unaligned(header->packet_id, &trailer->packet_id); 486 #if 0 487 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n", 488 header->hdr_len, header->packet_len, 489 header->packet_id); 490 #endif 491 return skb; 492 } 493 494 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf) 495 { 496 unsigned extra = sizeof (struct nc_header) 497 + 1 498 + sizeof (struct nc_trailer); 499 500 dev->net->hard_header_len += extra; 501 dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu; 502 dev->hard_mtu = NC_MAX_PACKET; 503 return usbnet_get_endpoints (dev, intf); 504 } 505 506 static const struct driver_info net1080_info = { 507 .description = "NetChip TurboCONNECT", 508 .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_NC, 509 .bind = net1080_bind, 510 .reset = net1080_reset, 511 .check_connect = net1080_check_connect, 512 .rx_fixup = net1080_rx_fixup, 513 .tx_fixup = net1080_tx_fixup, 514 }; 515 516 static const struct usb_device_id products [] = { 517 { 518 USB_DEVICE(0x0525, 0x1080), // NetChip ref design 519 .driver_info = (unsigned long) &net1080_info, 520 }, { 521 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold 522 .driver_info = (unsigned long) &net1080_info, 523 }, 524 { }, // END 525 }; 526 MODULE_DEVICE_TABLE(usb, products); 527 528 static struct usb_driver net1080_driver = { 529 .name = "net1080", 530 .id_table = products, 531 .probe = usbnet_probe, 532 .disconnect = usbnet_disconnect, 533 .suspend = usbnet_suspend, 534 .resume = usbnet_resume, 535 .disable_hub_initiated_lpm = 1, 536 }; 537 538 module_usb_driver(net1080_driver); 539 540 MODULE_AUTHOR("David Brownell"); 541 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links"); 542 MODULE_LICENSE("GPL"); 543