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, see <http://www.gnu.org/licenses/>.
19 // #define DEBUG // error path messages, extra info
20 // #define VERBOSE // more; success messages
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>
32 #include <asm/unaligned.h>
36 * Netchip 1080 driver ... http://www.netchip.com
37 * (Sept 2004: End-of-life announcement has been sent.)
38 * Used in (some) LapLink cables
41 #define frame_errors data[1]
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.
48 * - Ethernet header (14 bytes)
50 * - (optional padding byte, if needed so length becomes odd)
53 * This framing is to be avoided for non-NetChip devices.
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
62 // all else is optional, and must start with:
63 // __le16 vendorId; // from usb-if
67 #define PAD_BYTE ((unsigned char)0xAC)
73 // packets may use FLAG_FRAMING_NC and optional pad
74 #define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \
75 + sizeof (struct ethhdr) \
78 + sizeof (struct nc_trailer))
80 #define MIN_FRAMED FRAMED_SIZE(0)
82 /* packets _could_ be up to 64KB... */
83 #define NC_MAX_PACKET 32767
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.
92 #define NC_READ_TTL_MS ((u8)255) // ms
95 * We ignore most registers and EEPROM contents.
97 #define REG_USBCTL ((u8)0x04)
98 #define REG_TTL ((u8)0x10)
99 #define REG_STATUS ((u8)0x11)
102 * Vendor specific requests to read/write data
104 #define REQUEST_REGISTER ((u8)0x10)
105 #define REQUEST_EEPROM ((u8)0x11)
108 nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr)
110 int status = usbnet_read_cmd(dev, req,
111 USB_DIR_IN | USB_TYPE_VENDOR |
113 0, regnum, retval_ptr,
118 le16_to_cpus(retval_ptr);
123 nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr)
125 return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr);
128 // no retval ... can become async, usable in_interrupt()
130 nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value)
132 usbnet_write_cmd(dev, req,
133 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
134 value, regnum, NULL, 0);
138 nc_register_write(struct usbnet *dev, u8 regnum, u16 value)
140 nc_vendor_write(dev, REQUEST_REGISTER, regnum, value);
145 static void nc_dump_registers(struct usbnet *dev)
148 u16 *vp = kmalloc(sizeof (u16));
153 netdev_dbg(dev->net, "registers:\n");
154 for (reg = 0; reg < 0x20; reg++) {
157 // reading some registers is trouble
158 if (reg >= 0x08 && reg <= 0xf)
160 if (reg >= 0x12 && reg <= 0x1e)
163 retval = nc_register_read(dev, reg, vp);
165 netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n",
168 netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp);
175 /*-------------------------------------------------------------------------*/
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)
194 static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl)
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,
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" : "",
206 (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "",
207 (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "",
209 (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "",
210 (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "",
212 usbctl & ~USBCTL_WRITABLE_MASK);
215 /*-------------------------------------------------------------------------*/
221 #define STATUS_PORT_A (1 << 15)
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)
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)
233 #define STATUS_UNSPEC_MASK 0x0c8c
234 #define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK))
237 static inline void nc_dump_status(struct usbnet *dev, u16 status)
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,
244 // XXX the packet counts don't seem right
245 // (1 at reset, not 0); maybe UNSPEC too
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" : "",
253 STATUS_PACKETS_OTHER(status),
254 (status & STATUS_CONN_OTHER) ? " CON" : "",
255 (status & STATUS_SUSPEND_OTHER) ? " SUS" : "",
256 (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "",
258 status & STATUS_UNSPEC_MASK);
261 /*-------------------------------------------------------------------------*/
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))))
271 static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl)
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));
278 /*-------------------------------------------------------------------------*/
280 static int net1080_reset(struct usbnet *dev)
282 u16 usbctl, status, ttl;
286 // nc_dump_registers(dev);
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);
294 nc_dump_status(dev, status);
296 if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) {
297 netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval);
301 nc_dump_usbctl(dev, usbctl);
303 nc_register_write(dev, REG_USBCTL,
304 USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER);
306 if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) {
307 netdev_dbg(dev->net, "can't read TTL, %d\n", retval);
311 // nc_dump_ttl(dev, ttl);
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);
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");
326 static int net1080_check_connect(struct usbnet *dev)
332 retval = nc_register_read(dev, REG_STATUS, &vp);
335 netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval);
338 if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER)
343 static void nc_ensure_sync(struct usbnet *dev)
345 if (++dev->frame_errors <= 5)
348 if (usbnet_write_cmd_async(dev, REQUEST_REGISTER,
349 USB_DIR_OUT | USB_TYPE_VENDOR |
353 REG_USBCTL, NULL, 0))
356 netif_dbg(dev, rx_err, dev->net,
357 "flush net1080; too many framing errors\n");
358 dev->frame_errors = 0;
361 static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
363 struct nc_header *header;
364 struct nc_trailer *trailer;
365 u16 hdr_len, packet_len;
367 /* This check is no longer done by usbnet */
368 if (skb->len < dev->net->hard_header_len)
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,
375 dev->net->stats.rx_frame_errors++;
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);
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);
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);
397 // switch (vendor/product ids) { ... }
399 skb_pull(skb, hdr_len);
401 trailer = (struct nc_trailer *)
402 (skb->data + skb->len - sizeof *trailer);
403 skb_trim(skb, skb->len - sizeof *trailer);
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");
411 skb_trim(skb, skb->len - 1);
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);
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));
428 netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len,
429 header->packet_len, header->packet_id);
431 dev->frame_errors = 0;
435 static struct sk_buff *
436 net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
438 struct sk_buff *skb2;
439 struct nc_header *header = NULL;
440 struct nc_trailer *trailer = NULL;
441 int padlen = sizeof (struct nc_trailer);
444 if (!((len + padlen + sizeof (struct nc_header)) & 0x01))
446 if (!skb_cloned(skb)) {
447 int headroom = skb_headroom(skb);
448 int tailroom = skb_tailroom(skb);
450 if (padlen <= tailroom &&
451 sizeof(struct nc_header) <= headroom)
452 /* There's enough head and tail room */
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);
466 /* Create a new skb to use with the correct size */
467 skb2 = skb_copy_expand(skb,
468 sizeof (struct nc_header),
471 dev_kfree_skb_any(skb);
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++);
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);
489 netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n",
490 header->hdr_len, header->packet_len,
496 static int net1080_bind(struct usbnet *dev, struct usb_interface *intf)
498 unsigned extra = sizeof (struct nc_header)
500 + sizeof (struct nc_trailer);
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);
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,
518 static const struct usb_device_id products [] = {
520 USB_DEVICE(0x0525, 0x1080), // NetChip ref design
521 .driver_info = (unsigned long) &net1080_info,
523 USB_DEVICE(0x06D0, 0x0622), // Laplink Gold
524 .driver_info = (unsigned long) &net1080_info,
528 MODULE_DEVICE_TABLE(usb, products);
530 static struct usb_driver net1080_driver = {
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,
540 module_usb_driver(net1080_driver);
542 MODULE_AUTHOR("David Brownell");
543 MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links");
544 MODULE_LICENSE("GPL");