2 * Net1080 based USB host-to-host cables
3 * Copyright (C) 2000-2005 by David Brownell
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.
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.
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
20 // #define DEBUG // error path messages, extra info
21 // #define VERBOSE // more; success messages
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>
34 #include <asm/unaligned.h>
38 * Netchip 1080 driver ... http://www.netchip.com
39 * (Sept 2004: End-of-life announcement has been sent.)
40 * Used in (some) LapLink cables
43 #define frame_errors data[1]
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.
50 * - Ethernet header (14 bytes)
52 * - (optional padding byte, if needed so length becomes odd)
55 * This framing is to be avoided for non-NetChip devices.
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
64 // all else is optional, and must start with:
65 // __le16 vendorId; // from usb-if
69 #define PAD_BYTE ((unsigned char)0xAC)
75 // packets may use FLAG_FRAMING_NC and optional pad
76 #define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \
77 + sizeof (struct ethhdr) \
80 + sizeof (struct nc_trailer))
82 #define MIN_FRAMED FRAMED_SIZE(0)
84 /* packets _could_ be up to 64KB... */
85 #define NC_MAX_PACKET 32767
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.
94 #define NC_READ_TTL_MS ((u8)255) // ms
97 * We ignore most registers and EEPROM contents.
99 #define REG_USBCTL ((u8)0x04)
100 #define REG_TTL ((u8)0x10)
101 #define REG_STATUS ((u8)0x11)
104 * Vendor specific requests to read/write data
106 #define REQUEST_REGISTER ((u8)0x10)
107 #define REQUEST_EEPROM ((u8)0x11)
110 nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr)
112 int status = usbnet_read_cmd(dev, req,
113 USB_DIR_IN | USB_TYPE_VENDOR |
115 0, regnum, retval_ptr,
120 le16_to_cpus(retval_ptr);
125 nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr)
127 return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr);
130 // no retval ... can become async, usable in_interrupt()
132 nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value)
134 usbnet_write_cmd(dev, req,
135 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
136 value, regnum, NULL, 0);
140 nc_register_write(struct usbnet *dev, u8 regnum, u16 value)
142 nc_vendor_write(dev, REQUEST_REGISTER, regnum, value);
147 static void nc_dump_registers(struct usbnet *dev)
150 u16 *vp = kmalloc(sizeof (u16));
155 netdev_dbg(dev->net, "registers:\n");
156 for (reg = 0; reg < 0x20; reg++) {
159 // reading some registers is trouble
160 if (reg >= 0x08 && reg <= 0xf)
162 if (reg >= 0x12 && reg <= 0x1e)
165 retval = nc_register_read(dev, reg, vp);
167 netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n",
170 netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp);
177 /*-------------------------------------------------------------------------*/
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)
196 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl)
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,
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" : "",
208 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "",
209 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "",
211 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "",
212 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "",
214 usbctl & ~USBCTL_WRITABLE_MASK);
217 /*-------------------------------------------------------------------------*/
223 #define STATUS_PORT_A (1 << 15)
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)
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)
235 #define STATUS_UNSPEC_MASK 0x0c8c
236 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK))
239 static inline void nc_dump_status(struct usbnet *dev, u16 status)
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,
246 // XXX the packet counts don't seem right
247 // (1 at reset, not 0); maybe UNSPEC too
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" : "",
255 STATUS_PACKETS_OTHER(status),
256 (status & STATUS_CONN_OTHER) ? " CON" : "",
257 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "",
258 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "",
260 status & STATUS_UNSPEC_MASK);
263 /*-------------------------------------------------------------------------*/
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))))
273 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl)
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));
280 /*-------------------------------------------------------------------------*/
282 static int net1080_reset(struct usbnet *dev)
284 u16 usbctl, status, ttl;
288 // nc_dump_registers(dev);
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);
296 nc_dump_status(dev, status);
298 if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) {
299 netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval);
303 nc_dump_usbctl(dev, usbctl);
305 nc_register_write(dev, REG_USBCTL,
306 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER);
308 if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) {
309 netdev_dbg(dev->net, "can't read TTL, %d\n", retval);
313 // nc_dump_ttl(dev, ttl);
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);
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");
328 static int net1080_check_connect(struct usbnet *dev)
334 retval = nc_register_read(dev, REG_STATUS, &vp);
337 netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval);
340 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER)
345 static void nc_ensure_sync(struct usbnet *dev)
347 if (++dev->frame_errors <= 5)
350 if (usbnet_write_cmd_async(dev, REQUEST_REGISTER,
351 USB_DIR_OUT | USB_TYPE_VENDOR |
355 REG_USBCTL, NULL, 0))
358 netif_dbg(dev, rx_err, dev->net,
359 "flush net1080; too many framing errors\n");
360 dev->frame_errors = 0;
363 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
365 struct nc_header *header;
366 struct nc_trailer *trailer;
367 u16 hdr_len, packet_len;
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,
373 dev->net->stats.rx_frame_errors++;
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);
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);
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);
395 // switch (vendor/product ids) { ... }
397 skb_pull(skb, hdr_len);
399 trailer = (struct nc_trailer *)
400 (skb->data + skb->len - sizeof *trailer);
401 skb_trim(skb, skb->len - sizeof *trailer);
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");
409 skb_trim(skb, skb->len - 1);
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);
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));
426 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len,
427 header->packet_len, header->packet_id);
429 dev->frame_errors = 0;
433 static struct sk_buff *
434 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
436 struct sk_buff *skb2;
437 struct nc_header *header = NULL;
438 struct nc_trailer *trailer = NULL;
439 int padlen = sizeof (struct nc_trailer);
442 if (!((len + padlen + sizeof (struct nc_header)) & 0x01))
444 if (!skb_cloned(skb)) {
445 int headroom = skb_headroom(skb);
446 int tailroom = skb_tailroom(skb);
448 if (padlen <= tailroom &&
449 sizeof(struct nc_header) <= headroom)
450 /* There's enough head and tail room */
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);
464 /* Create a new skb to use with the correct size */
465 skb2 = skb_copy_expand(skb,
466 sizeof (struct nc_header),
469 dev_kfree_skb_any(skb);
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++);
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);
487 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n",
488 header->hdr_len, header->packet_len,
494 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf)
496 unsigned extra = sizeof (struct nc_header)
498 + sizeof (struct nc_trailer);
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);
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,
516 static const struct usb_device_id products [] = {
518 USB_DEVICE(0x0525, 0x1080), // NetChip ref design
519 .driver_info = (unsigned long) &net1080_info,
521 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold
522 .driver_info = (unsigned long) &net1080_info,
526 MODULE_DEVICE_TABLE(usb, products);
528 static struct usb_driver net1080_driver = {
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,
538 module_usb_driver(net1080_driver);
540 MODULE_AUTHOR("David Brownell");
541 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links");
542 MODULE_LICENSE("GPL");