--- /dev/null
+/*
+ * Net1080 based USB host-to-host cables
+ * Copyright (C) 2000-2005 by David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+// #define DEBUG // error path messages, extra info
+// #define VERBOSE // more; success messages
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/workqueue.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <linux/slab.h>
+
+#include <asm/unaligned.h>
+
+
+/*
+ * Netchip 1080 driver ... http://www.netchip.com
+ * (Sept 2004: End-of-life announcement has been sent.)
+ * Used in (some) LapLink cables
+ */
+
+#define frame_errors data[1]
+
+/*
+ * NetChip framing of ethernet packets, supporting additional error
+ * checks for links that may drop bulk packets from inside messages.
+ * Odd USB length == always short read for last usb packet.
+ * - nc_header
+ * - Ethernet header (14 bytes)
+ * - payload
+ * - (optional padding byte, if needed so length becomes odd)
+ * - nc_trailer
+ *
+ * This framing is to be avoided for non-NetChip devices.
+ */
+
+struct nc_header { // packed:
+ __le16 hdr_len; // sizeof nc_header (LE, all)
+ __le16 packet_len; // payload size (including ethhdr)
+ __le16 packet_id; // detects dropped packets
+#define MIN_HEADER 6
+
+ // all else is optional, and must start with:
+ // __le16 vendorId; // from usb-if
+ // __le16 productId;
+} __packed;
+
+#define PAD_BYTE ((unsigned char)0xAC)
+
+struct nc_trailer {
+ __le16 packet_id;
+} __packed;
+
+// packets may use FLAG_FRAMING_NC and optional pad
+#define FRAMED_SIZE(mtu) (sizeof (struct nc_header) \
+ + sizeof (struct ethhdr) \
+ + (mtu) \
+ + 1 \
+ + sizeof (struct nc_trailer))
+
+#define MIN_FRAMED FRAMED_SIZE(0)
+
+/* packets _could_ be up to 64KB... */
+#define NC_MAX_PACKET 32767
+
+
+/*
+ * Zero means no timeout; else, how long a 64 byte bulk packet may be queued
+ * before the hardware drops it. If that's done, the driver will need to
+ * frame network packets to guard against the dropped USB packets. The win32
+ * driver sets this for both sides of the link.
+ */
+#define NC_READ_TTL_MS ((u8)255) // ms
+
+/*
+ * We ignore most registers and EEPROM contents.
+ */
+#define REG_USBCTL ((u8)0x04)
+#define REG_TTL ((u8)0x10)
+#define REG_STATUS ((u8)0x11)
+
+/*
+ * Vendor specific requests to read/write data
+ */
+#define REQUEST_REGISTER ((u8)0x10)
+#define REQUEST_EEPROM ((u8)0x11)
+
+static int
+nc_vendor_read(struct usbnet *dev, u8 req, u8 regnum, u16 *retval_ptr)
+{
+ int status = usbnet_read_cmd(dev, req,
+ USB_DIR_IN | USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE,
+ 0, regnum, retval_ptr,
+ sizeof *retval_ptr);
+ if (status > 0)
+ status = 0;
+ if (!status)
+ le16_to_cpus(retval_ptr);
+ return status;
+}
+
+static inline int
+nc_register_read(struct usbnet *dev, u8 regnum, u16 *retval_ptr)
+{
+ return nc_vendor_read(dev, REQUEST_REGISTER, regnum, retval_ptr);
+}
+
+// no retval ... can become async, usable in_interrupt()
+static void
+nc_vendor_write(struct usbnet *dev, u8 req, u8 regnum, u16 value)
+{
+ usbnet_write_cmd(dev, req,
+ USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ value, regnum, NULL, 0);
+}
+
+static inline void
+nc_register_write(struct usbnet *dev, u8 regnum, u16 value)
+{
+ nc_vendor_write(dev, REQUEST_REGISTER, regnum, value);
+}
+
+
+#if 0
+static void nc_dump_registers(struct usbnet *dev)
+{
+ u8 reg;
+ u16 *vp = kmalloc(sizeof (u16));
+
+ if (!vp)
+ return;
+
+ netdev_dbg(dev->net, "registers:\n");
+ for (reg = 0; reg < 0x20; reg++) {
+ int retval;
+
+ // reading some registers is trouble
+ if (reg >= 0x08 && reg <= 0xf)
+ continue;
+ if (reg >= 0x12 && reg <= 0x1e)
+ continue;
+
+ retval = nc_register_read(dev, reg, vp);
+ if (retval < 0)
+ netdev_dbg(dev->net, "reg [0x%x] ==> error %d\n",
+ reg, retval);
+ else
+ netdev_dbg(dev->net, "reg [0x%x] = 0x%x\n", reg, *vp);
+ }
+ kfree(vp);
+}
+#endif
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Control register
+ */
+
+#define USBCTL_WRITABLE_MASK 0x1f0f
+// bits 15-13 reserved, r/o
+#define USBCTL_ENABLE_LANG (1 << 12)
+#define USBCTL_ENABLE_MFGR (1 << 11)
+#define USBCTL_ENABLE_PROD (1 << 10)
+#define USBCTL_ENABLE_SERIAL (1 << 9)
+#define USBCTL_ENABLE_DEFAULTS (1 << 8)
+// bits 7-4 reserved, r/o
+#define USBCTL_FLUSH_OTHER (1 << 3)
+#define USBCTL_FLUSH_THIS (1 << 2)
+#define USBCTL_DISCONN_OTHER (1 << 1)
+#define USBCTL_DISCONN_THIS (1 << 0)
+
+static inline void nc_dump_usbctl(struct usbnet *dev, u16 usbctl)
+{
+ netif_dbg(dev, link, dev->net,
+ "net1080 %s-%s usbctl 0x%x:%s%s%s%s%s; this%s%s; other%s%s; r/o 0x%x\n",
+ dev->udev->bus->bus_name, dev->udev->devpath,
+ usbctl,
+ (usbctl & USBCTL_ENABLE_LANG) ? " lang" : "",
+ (usbctl & USBCTL_ENABLE_MFGR) ? " mfgr" : "",
+ (usbctl & USBCTL_ENABLE_PROD) ? " prod" : "",
+ (usbctl & USBCTL_ENABLE_SERIAL) ? " serial" : "",
+ (usbctl & USBCTL_ENABLE_DEFAULTS) ? " defaults" : "",
+
+ (usbctl & USBCTL_FLUSH_THIS) ? " FLUSH" : "",
+ (usbctl & USBCTL_DISCONN_THIS) ? " DIS" : "",
+
+ (usbctl & USBCTL_FLUSH_OTHER) ? " FLUSH" : "",
+ (usbctl & USBCTL_DISCONN_OTHER) ? " DIS" : "",
+
+ usbctl & ~USBCTL_WRITABLE_MASK);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Status register
+ */
+
+#define STATUS_PORT_A (1 << 15)
+
+#define STATUS_CONN_OTHER (1 << 14)
+#define STATUS_SUSPEND_OTHER (1 << 13)
+#define STATUS_MAILBOX_OTHER (1 << 12)
+#define STATUS_PACKETS_OTHER(n) (((n) >> 8) & 0x03)
+
+#define STATUS_CONN_THIS (1 << 6)
+#define STATUS_SUSPEND_THIS (1 << 5)
+#define STATUS_MAILBOX_THIS (1 << 4)
+#define STATUS_PACKETS_THIS(n) (((n) >> 0) & 0x03)
+
+#define STATUS_UNSPEC_MASK 0x0c8c
+#define STATUS_NOISE_MASK ((u16)~(0x0303|STATUS_UNSPEC_MASK))
+
+
+static inline void nc_dump_status(struct usbnet *dev, u16 status)
+{
+ netif_dbg(dev, link, dev->net,
+ "net1080 %s-%s status 0x%x: this (%c) PKT=%d%s%s%s; other PKT=%d%s%s%s; unspec 0x%x\n",
+ dev->udev->bus->bus_name, dev->udev->devpath,
+ status,
+
+ // XXX the packet counts don't seem right
+ // (1 at reset, not 0); maybe UNSPEC too
+
+ (status & STATUS_PORT_A) ? 'A' : 'B',
+ STATUS_PACKETS_THIS(status),
+ (status & STATUS_CONN_THIS) ? " CON" : "",
+ (status & STATUS_SUSPEND_THIS) ? " SUS" : "",
+ (status & STATUS_MAILBOX_THIS) ? " MBOX" : "",
+
+ STATUS_PACKETS_OTHER(status),
+ (status & STATUS_CONN_OTHER) ? " CON" : "",
+ (status & STATUS_SUSPEND_OTHER) ? " SUS" : "",
+ (status & STATUS_MAILBOX_OTHER) ? " MBOX" : "",
+
+ status & STATUS_UNSPEC_MASK);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * TTL register
+ */
+
+#define TTL_THIS(ttl) (0x00ff & ttl)
+#define TTL_OTHER(ttl) (0x00ff & (ttl >> 8))
+#define MK_TTL(this,other) ((u16)(((other)<<8)|(0x00ff&(this))))
+
+static inline void nc_dump_ttl(struct usbnet *dev, u16 ttl)
+{
+ netif_dbg(dev, link, dev->net, "net1080 %s-%s ttl 0x%x this = %d, other = %d\n",
+ dev->udev->bus->bus_name, dev->udev->devpath,
+ ttl, TTL_THIS(ttl), TTL_OTHER(ttl));
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int net1080_reset(struct usbnet *dev)
+{
+ u16 usbctl, status, ttl;
+ u16 vp;
+ int retval;
+
+ // nc_dump_registers(dev);
+
+ if ((retval = nc_register_read(dev, REG_STATUS, &vp)) < 0) {
+ netdev_dbg(dev->net, "can't read %s-%s status: %d\n",
+ dev->udev->bus->bus_name, dev->udev->devpath, retval);
+ goto done;
+ }
+ status = vp;
+ nc_dump_status(dev, status);
+
+ if ((retval = nc_register_read(dev, REG_USBCTL, &vp)) < 0) {
+ netdev_dbg(dev->net, "can't read USBCTL, %d\n", retval);
+ goto done;
+ }
+ usbctl = vp;
+ nc_dump_usbctl(dev, usbctl);
+
+ nc_register_write(dev, REG_USBCTL,
+ USBCTL_FLUSH_THIS | USBCTL_FLUSH_OTHER);
+
+ if ((retval = nc_register_read(dev, REG_TTL, &vp)) < 0) {
+ netdev_dbg(dev->net, "can't read TTL, %d\n", retval);
+ goto done;
+ }
+ ttl = vp;
+ // nc_dump_ttl(dev, ttl);
+
+ nc_register_write(dev, REG_TTL,
+ MK_TTL(NC_READ_TTL_MS, TTL_OTHER(ttl)) );
+ netdev_dbg(dev->net, "assigned TTL, %d ms\n", NC_READ_TTL_MS);
+
+ netif_info(dev, link, dev->net, "port %c, peer %sconnected\n",
+ (status & STATUS_PORT_A) ? 'A' : 'B',
+ (status & STATUS_CONN_OTHER) ? "" : "dis");
+ retval = 0;
+
+done:
+ return retval;
+}
+
+static int net1080_check_connect(struct usbnet *dev)
+{
+ int retval;
+ u16 status;
+ u16 vp;
+
+ retval = nc_register_read(dev, REG_STATUS, &vp);
+ status = vp;
+ if (retval != 0) {
+ netdev_dbg(dev->net, "net1080_check_conn read - %d\n", retval);
+ return retval;
+ }
+ if ((status & STATUS_CONN_OTHER) != STATUS_CONN_OTHER)
+ return -ENOLINK;
+ return 0;
+}
+
+static void nc_ensure_sync(struct usbnet *dev)
+{
+ if (++dev->frame_errors <= 5)
+ return;
+
+ if (usbnet_write_cmd_async(dev, REQUEST_REGISTER,
+ USB_DIR_OUT | USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE,
+ USBCTL_FLUSH_THIS |
+ USBCTL_FLUSH_OTHER,
+ REG_USBCTL, NULL, 0))
+ return;
+
+ netif_dbg(dev, rx_err, dev->net,
+ "flush net1080; too many framing errors\n");
+ dev->frame_errors = 0;
+}
+
+static int net1080_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+{
+ struct nc_header *header;
+ struct nc_trailer *trailer;
+ u16 hdr_len, packet_len;
+
+ /* This check is no longer done by usbnet */
+ if (skb->len < dev->net->hard_header_len)
+ return 0;
+
+ if (!(skb->len & 0x01)) {
+ netdev_dbg(dev->net, "rx framesize %d range %d..%d mtu %d\n",
+ skb->len, dev->net->hard_header_len, dev->hard_mtu,
+ dev->net->mtu);
+ dev->net->stats.rx_frame_errors++;
+ nc_ensure_sync(dev);
+ return 0;
+ }
+
+ header = (struct nc_header *) skb->data;
+ hdr_len = le16_to_cpup(&header->hdr_len);
+ packet_len = le16_to_cpup(&header->packet_len);
+ if (FRAMED_SIZE(packet_len) > NC_MAX_PACKET) {
+ dev->net->stats.rx_frame_errors++;
+ netdev_dbg(dev->net, "packet too big, %d\n", packet_len);
+ nc_ensure_sync(dev);
+ return 0;
+ } else if (hdr_len < MIN_HEADER) {
+ dev->net->stats.rx_frame_errors++;
+ netdev_dbg(dev->net, "header too short, %d\n", hdr_len);
+ nc_ensure_sync(dev);
+ return 0;
+ } else if (hdr_len > MIN_HEADER) {
+ // out of band data for us?
+ netdev_dbg(dev->net, "header OOB, %d bytes\n", hdr_len - MIN_HEADER);
+ nc_ensure_sync(dev);
+ // switch (vendor/product ids) { ... }
+ }
+ skb_pull(skb, hdr_len);
+
+ trailer = (struct nc_trailer *)
+ (skb->data + skb->len - sizeof *trailer);
+ skb_trim(skb, skb->len - sizeof *trailer);
+
+ if ((packet_len & 0x01) == 0) {
+ if (skb->data [packet_len] != PAD_BYTE) {
+ dev->net->stats.rx_frame_errors++;
+ netdev_dbg(dev->net, "bad pad\n");
+ return 0;
+ }
+ skb_trim(skb, skb->len - 1);
+ }
+ if (skb->len != packet_len) {
+ dev->net->stats.rx_frame_errors++;
+ netdev_dbg(dev->net, "bad packet len %d (expected %d)\n",
+ skb->len, packet_len);
+ nc_ensure_sync(dev);
+ return 0;
+ }
+ if (header->packet_id != get_unaligned(&trailer->packet_id)) {
+ dev->net->stats.rx_fifo_errors++;
+ netdev_dbg(dev->net, "(2+ dropped) rx packet_id mismatch 0x%x 0x%x\n",
+ le16_to_cpu(header->packet_id),
+ le16_to_cpu(trailer->packet_id));
+ return 0;
+ }
+#if 0
+ netdev_dbg(dev->net, "frame <rx h %d p %d id %d\n", header->hdr_len,
+ header->packet_len, header->packet_id);
+#endif
+ dev->frame_errors = 0;
+ return 1;
+}
+
+static struct sk_buff *
+net1080_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
+{
+ struct sk_buff *skb2;
+ struct nc_header *header = NULL;
+ struct nc_trailer *trailer = NULL;
+ int padlen = sizeof (struct nc_trailer);
+ int len = skb->len;
+
+ if (!((len + padlen + sizeof (struct nc_header)) & 0x01))
+ padlen++;
+ if (!skb_cloned(skb)) {
+ int headroom = skb_headroom(skb);
+ int tailroom = skb_tailroom(skb);
+
+ if (padlen <= tailroom &&
+ sizeof(struct nc_header) <= headroom)
+ /* There's enough head and tail room */
+ goto encapsulate;
+
+ if ((sizeof (struct nc_header) + padlen) <
+ (headroom + tailroom)) {
+ /* There's enough total room, so just readjust */
+ skb->data = memmove(skb->head
+ + sizeof (struct nc_header),
+ skb->data, skb->len);
+ skb_set_tail_pointer(skb, len);
+ goto encapsulate;
+ }
+ }
+
+ /* Create a new skb to use with the correct size */
+ skb2 = skb_copy_expand(skb,
+ sizeof (struct nc_header),
+ padlen,
+ flags);
+ dev_kfree_skb_any(skb);
+ if (!skb2)
+ return skb2;
+ skb = skb2;
+
+encapsulate:
+ /* header first */
+ header = (struct nc_header *) skb_push(skb, sizeof *header);
+ header->hdr_len = cpu_to_le16(sizeof (*header));
+ header->packet_len = cpu_to_le16(len);
+ header->packet_id = cpu_to_le16((u16)dev->xid++);
+
+ /* maybe pad; then trailer */
+ if (!((skb->len + sizeof *trailer) & 0x01))
+ *skb_put(skb, 1) = PAD_BYTE;
+ trailer = (struct nc_trailer *) skb_put(skb, sizeof *trailer);
+ put_unaligned(header->packet_id, &trailer->packet_id);
+#if 0
+ netdev_dbg(dev->net, "frame >tx h %d p %d id %d\n",
+ header->hdr_len, header->packet_len,
+ header->packet_id);
+#endif
+ return skb;
+}
+
+static int net1080_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+ unsigned extra = sizeof (struct nc_header)
+ + 1
+ + sizeof (struct nc_trailer);
+
+ dev->net->hard_header_len += extra;
+ dev->rx_urb_size = dev->net->hard_header_len + dev->net->mtu;
+ dev->hard_mtu = NC_MAX_PACKET;
+ return usbnet_get_endpoints (dev, intf);
+}
+
+static const struct driver_info net1080_info = {
+ .description = "NetChip TurboCONNECT",
+ .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_NC,
+ .bind = net1080_bind,
+ .reset = net1080_reset,
+ .check_connect = net1080_check_connect,
+ .rx_fixup = net1080_rx_fixup,
+ .tx_fixup = net1080_tx_fixup,
+};
+
+static const struct usb_device_id products [] = {
+{
+ USB_DEVICE(0x0525, 0x1080), // NetChip ref design
+ .driver_info = (unsigned long) &net1080_info,
+}, {
+ USB_DEVICE(0x06D0, 0x0622), // Laplink Gold
+ .driver_info = (unsigned long) &net1080_info,
+},
+ { }, // END
+};
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver net1080_driver = {
+ .name = "net1080",
+ .id_table = products,
+ .probe = usbnet_probe,
+ .disconnect = usbnet_disconnect,
+ .suspend = usbnet_suspend,
+ .resume = usbnet_resume,
+ .disable_hub_initiated_lpm = 1,
+};
+
+module_usb_driver(net1080_driver);
+
+MODULE_AUTHOR("David Brownell");
+MODULE_DESCRIPTION("NetChip 1080 based USB Host-to-Host Links");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff