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