xref: /src/sys/dev/usb/if_cue.c

/*	$NetBSD: if_cue.c,v 1.68.4.16 2017/09/01 13:45:24 skrll Exp $	*/
/*
 * Copyright (c) 1997, 1998, 1999, 2000
 *	Bill Paul <wpaul (at) ee.columbia.edu>.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Bill Paul.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $FreeBSD: src/sys/dev/usb/if_cue.c,v 1.4 2000/01/16 22:45:06 wpaul Exp $
 */

/*
 * CATC USB-EL1210A USB to ethernet driver. Used in the CATC Netmate
 * adapters and others.
 *
 * Written by Bill Paul <wpaul (at) ee.columbia.edu>
 * Electrical Engineering Department
 * Columbia University, New York City
 */

/*
 * The CATC USB-EL1210A provides USB ethernet support at 10Mbps. The
 * RX filter uses a 512-bit multicast hash table, single perfect entry
 * for the station address, and promiscuous mode. Unlike the ADMtek
 * and KLSI chips, the CATC ASIC supports read and write combining
 * mode where multiple packets can be transfered using a single bulk
 * transaction, which helps performance a great deal.
 */

/*
 * Ported to NetBSD and somewhat rewritten by Lennart Augustsson.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_cue.c,v 1.68.4.16 2017/09/01 13:45:24 skrll Exp $");

#ifdef _KERNEL_OPT
#include "opt_inet.h"
#include "opt_usb.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/bus.h>
#include <sys/device.h>

#include <net/if.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/bpf.h>
#include <net/if_ether.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/if_inarp.h>
#endif

#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>
#include <dev/usb/usbdivar.h>
#include <dev/usb/usbdevs.h>

#include <dev/usb/if_cuereg.h>

#ifdef CUE_DEBUG
#define DPRINTF(x)	if (cuedebug) printf x
#define DPRINTFN(n,x)	if (cuedebug >= (n)) printf x
int	cuedebug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n,x)
#endif

/*
 * Various supported device vendors/products.
 */
Static struct usb_devno cue_devs[] = {
	{ USB_VENDOR_CATC, USB_PRODUCT_CATC_NETMATE },
	{ USB_VENDOR_CATC, USB_PRODUCT_CATC_NETMATE2 },
	{ USB_VENDOR_SMARTBRIDGES, USB_PRODUCT_SMARTBRIDGES_SMARTLINK },
	/* Belkin F5U111 adapter covered by NETMATE entry */
};
#define cue_lookup(v, p) (usb_lookup(cue_devs, v, p))

int cue_match(device_t, cfdata_t, void *);
void cue_attach(device_t, device_t, void *);
int cue_detach(device_t, int);
int cue_activate(device_t, enum devact);
extern struct cfdriver cue_cd;
CFATTACH_DECL_NEW(cue, sizeof(struct cue_softc), cue_match, cue_attach,
    cue_detach, cue_activate);

Static int cue_tx_list_init(struct cue_softc *);
Static void cue_tx_list_free(struct cue_softc *);
Static int cue_rx_list_init(struct cue_softc *);
#if 0
Static void cue_rx_list_free(struct cue_softc *);
#endif
Static int cue_newbuf(struct cue_softc *, struct cue_chain *, struct mbuf *);
Static int cue_send(struct cue_softc *, struct mbuf *, int);
Static void cue_rxeof(struct usbd_xfer *, void *, usbd_status);
Static void cue_txeof(struct usbd_xfer *, void *, usbd_status);
Static void cue_tick(void *);
Static void cue_tick_task(void *);
Static void cue_start(struct ifnet *);
Static void cue_start_locked(struct ifnet *);
Static int cue_ioctl(struct ifnet *, u_long, void *);
Static int cue_ifflags_cb(struct ethercom *);
Static int cue_init(struct ifnet *);
Static int cue_init_locked(struct ifnet *);
Static void cue_stop(struct cue_softc *);
Static void cue_stop_locked(struct cue_softc *);
Static void cue_watchdog(struct ifnet *);

Static void cue_setmulti(struct cue_softc *);
Static uint32_t cue_crc(const char *);
Static void cue_reset(struct cue_softc *);

Static int cue_csr_read_1(struct cue_softc *, int);
Static int cue_csr_write_1(struct cue_softc *, int, int);
Static int cue_csr_read_2(struct cue_softc *, int);
#if 0
Static int cue_csr_write_2(struct cue_softc *, int, int);
#endif
Static int cue_mem(struct cue_softc *, int, int, void *, int);
Static int cue_getmac(struct cue_softc *, void *);

#define CUE_SETBIT(sc, reg, x)				\
	cue_csr_write_1(sc, reg, cue_csr_read_1(sc, reg) | (x))

#define CUE_CLRBIT(sc, reg, x)				\
	cue_csr_write_1(sc, reg, cue_csr_read_1(sc, reg) & ~(x))

Static int
cue_csr_read_1(struct cue_softc	*sc, int reg)
{
	usb_device_request_t	req;
	usbd_status		err;
	uint8_t			val = 0;

	if (sc->cue_dying)
		return 0;

	req.bmRequestType = UT_READ_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_READREG;
	USETW(req.wValue, 0);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 1);

	err = usbd_do_request(sc->cue_udev, &req, &val);

	if (err) {
		DPRINTF(("%s: cue_csr_read_1: reg=0x%x err=%s\n",
		    device_xname(sc->cue_dev), reg, usbd_errstr(err)));
		return 0;
	}

	DPRINTFN(10,("%s: cue_csr_read_1 reg=0x%x val=0x%x\n",
	    device_xname(sc->cue_dev), reg, val));

	return val;
}

Static int
cue_csr_read_2(struct cue_softc	*sc, int reg)
{
	usb_device_request_t	req;
	usbd_status		err;
	uWord			val;

	if (sc->cue_dying)
		return 0;

	req.bmRequestType = UT_READ_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_READREG;
	USETW(req.wValue, 0);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 2);

	err = usbd_do_request(sc->cue_udev, &req, &val);

	DPRINTFN(10,("%s: cue_csr_read_2 reg=0x%x val=0x%x\n",
	    device_xname(sc->cue_dev), reg, UGETW(val)));

	if (err) {
		DPRINTF(("%s: cue_csr_read_2: reg=0x%x err=%s\n",
		    device_xname(sc->cue_dev), reg, usbd_errstr(err)));
		return 0;
	}

	return UGETW(val);
}

Static int
cue_csr_write_1(struct cue_softc *sc, int reg, int val)
{
	usb_device_request_t	req;
	usbd_status		err;

	if (sc->cue_dying)
		return 0;

	DPRINTFN(10,("%s: cue_csr_write_1 reg=0x%x val=0x%x\n",
	    device_xname(sc->cue_dev), reg, val));

	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_WRITEREG;
	USETW(req.wValue, val);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 0);

	err = usbd_do_request(sc->cue_udev, &req, NULL);

	if (err) {
		DPRINTF(("%s: cue_csr_write_1: reg=0x%x err=%s\n",
		    device_xname(sc->cue_dev), reg, usbd_errstr(err)));
		return -1;
	}

	DPRINTFN(20,("%s: cue_csr_write_1, after reg=0x%x val=0x%x\n",
	    device_xname(sc->cue_dev), reg, cue_csr_read_1(sc, reg)));

	return 0;
}

#if 0
Static int
cue_csr_write_2(struct cue_softc *sc, int reg, int aval)
{
	usb_device_request_t	req;
	usbd_status		err;
	uWord			val;
	int			s;

	if (sc->cue_dying)
		return 0;

	DPRINTFN(10,("%s: cue_csr_write_2 reg=0x%x val=0x%x\n",
	    device_xname(sc->cue_dev), reg, aval));

	USETW(val, aval);
	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_WRITEREG;
	USETW(req.wValue, val);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 0);

	err = usbd_do_request(sc->cue_udev, &req, NULL);

	if (err) {
		DPRINTF(("%s: cue_csr_write_2: reg=0x%x err=%s\n",
		    device_xname(sc->cue_dev), reg, usbd_errstr(err)));
		return -1;
	}

	return 0;
}
#endif

Static int
cue_mem(struct cue_softc *sc, int cmd, int addr, void *buf, int len)
{
	usb_device_request_t	req;
	usbd_status		err;

	DPRINTFN(10,("%s: cue_mem cmd=0x%x addr=0x%x len=%d\n",
	    device_xname(sc->cue_dev), cmd, addr, len));

	if (cmd == CUE_CMD_READSRAM)
		req.bmRequestType = UT_READ_VENDOR_DEVICE;
	else
		req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = cmd;
	USETW(req.wValue, 0);
	USETW(req.wIndex, addr);
	USETW(req.wLength, len);

	err = usbd_do_request(sc->cue_udev, &req, buf);

	if (err) {
		DPRINTF(("%s: cue_csr_mem: addr=0x%x err=%s\n",
		    device_xname(sc->cue_dev), addr, usbd_errstr(err)));
		return -1;
	}

	return 0;
}

Static int
cue_getmac(struct cue_softc *sc, void *buf)
{
	usb_device_request_t	req;
	usbd_status		err;

	DPRINTFN(10,("%s: cue_getmac\n", device_xname(sc->cue_dev)));

	req.bmRequestType = UT_READ_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_GET_MACADDR;
	USETW(req.wValue, 0);
	USETW(req.wIndex, 0);
	USETW(req.wLength, ETHER_ADDR_LEN);

	err = usbd_do_request(sc->cue_udev, &req, buf);

	if (err) {
		printf("%s: read MAC address failed\n",
		    device_xname(sc->cue_dev));
		return -1;
	}

	return 0;
}

#define CUE_POLY	0xEDB88320
#define CUE_BITS	9

Static uint32_t
cue_crc(const char *addr)
{
	uint32_t		idx, bit, data, crc;

	/* Compute CRC for the address value. */
	crc = 0xFFFFFFFF; /* initial value */

	for (idx = 0; idx < 6; idx++) {
		for (data = *addr++, bit = 0; bit < 8; bit++, data >>= 1)
			crc = (crc >> 1) ^ (((crc ^ data) & 1) ? CUE_POLY : 0);
	}

	return crc & ((1 << CUE_BITS) - 1);
}

Static void
cue_setmulti(struct cue_softc *sc)
{
	struct ifnet		*ifp;
	struct ether_multi	*enm;
	struct ether_multistep	step;
	uint32_t		h, i;

	ifp = GET_IFP(sc);

	DPRINTFN(2,("%s: cue_setmulti if_flags=0x%x\n",
	    device_xname(sc->cue_dev), ifp->if_flags));

	if (ifp->if_flags & IFF_PROMISC) {
allmulti:
		ifp->if_flags |= IFF_ALLMULTI;
		for (i = 0; i < CUE_MCAST_TABLE_LEN; i++)
			sc->cue_mctab[i] = 0xFF;
		cue_mem(sc, CUE_CMD_WRITESRAM, CUE_MCAST_TABLE_ADDR,
		    &sc->cue_mctab, CUE_MCAST_TABLE_LEN);
		return;
	}

	/* first, zot all the existing hash bits */
	for (i = 0; i < CUE_MCAST_TABLE_LEN; i++)
		sc->cue_mctab[i] = 0;

	/* now program new ones */
	ETHER_FIRST_MULTI(step, &sc->cue_ec, enm);
	while (enm != NULL) {
		if (memcmp(enm->enm_addrlo,
		    enm->enm_addrhi, ETHER_ADDR_LEN) != 0)
			goto allmulti;

		h = cue_crc(enm->enm_addrlo);
		sc->cue_mctab[h >> 3] |= 1 << (h & 0x7);
		ETHER_NEXT_MULTI(step, enm);
	}

	ifp->if_flags &= ~IFF_ALLMULTI;

	/*
	 * Also include the broadcast address in the filter
	 * so we can receive broadcast frames.
	 */
	if (ifp->if_flags & IFF_BROADCAST) {
		h = cue_crc(etherbroadcastaddr);
		sc->cue_mctab[h >> 3] |= 1 << (h & 0x7);
	}

	cue_mem(sc, CUE_CMD_WRITESRAM, CUE_MCAST_TABLE_ADDR,
	    &sc->cue_mctab, CUE_MCAST_TABLE_LEN);
}

Static void
cue_reset(struct cue_softc *sc)
{
	usb_device_request_t	req;
	usbd_status		err;

	DPRINTFN(2,("%s: cue_reset\n", device_xname(sc->cue_dev)));

	if (sc->cue_dying)
		return;

	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = CUE_CMD_RESET;
	USETW(req.wValue, 0);
	USETW(req.wIndex, 0);
	USETW(req.wLength, 0);

	err = usbd_do_request(sc->cue_udev, &req, NULL);

	if (err)
		printf("%s: reset failed\n", device_xname(sc->cue_dev));

	/* Wait a little while for the chip to get its brains in order. */
	usbd_delay_ms(sc->cue_udev, 1);
}

/*
 * Probe for a CATC chip.
 */
int
cue_match(device_t parent, cfdata_t match, void *aux)
{
	struct usb_attach_arg *uaa = aux;

	return cue_lookup(uaa->uaa_vendor, uaa->uaa_product) != NULL ?
		UMATCH_VENDOR_PRODUCT : UMATCH_NONE;
}

/*
 * Attach the interface. Allocate softc structures, do ifmedia
 * setup and ethernet/BPF attach.
 */
void
cue_attach(device_t parent, device_t self, void *aux)
{
	struct cue_softc *sc = device_private(self);
	struct usb_attach_arg *uaa = aux;
	char			*devinfop;
	u_char			eaddr[ETHER_ADDR_LEN];
	struct usbd_device *	dev = uaa->uaa_device;
	struct usbd_interface *	iface;
	usbd_status		err;
	struct ifnet		*ifp;
	usb_interface_descriptor_t	*id;
	usb_endpoint_descriptor_t	*ed;
	int			i;

	DPRINTFN(5,(" : cue_attach: sc=%p, dev=%p", sc, dev));

	sc->cue_dev = self;

	aprint_naive("\n");
	aprint_normal("\n");

	devinfop = usbd_devinfo_alloc(dev, 0);
	aprint_normal_dev(self, "%s\n", devinfop);
	usbd_devinfo_free(devinfop);

	err = usbd_set_config_no(dev, CUE_CONFIG_NO, 1);
	if (err) {
		aprint_error_dev(self, "failed to set configuration"
		    ", err=%s\n", usbd_errstr(err));
		return;
	}

	sc->cue_udev = dev;
	sc->cue_product = uaa->uaa_product;
	sc->cue_vendor = uaa->uaa_vendor;

	usb_init_task(&sc->cue_tick_task, cue_tick_task, sc, 0);
	usb_init_task(&sc->cue_stop_task, (void (*)(void *))cue_stop, sc, 0);

	mutex_init(&sc->cue_lock, MUTEX_DEFAULT, IPL_NONE);
	mutex_init(&sc->cue_txlock, MUTEX_DEFAULT, IPL_SOFTUSB);
	mutex_init(&sc->cue_rxlock, MUTEX_DEFAULT, IPL_SOFTUSB);

	err = usbd_device2interface_handle(dev, CUE_IFACE_IDX, &iface);
	if (err) {
		aprint_error_dev(self, "getting interface handle failed\n");
		return;
	}

	sc->cue_iface = iface;
	id = usbd_get_interface_descriptor(iface);

	/* Find endpoints. */
	for (i = 0; i < id->bNumEndpoints; i++) {
		ed = usbd_interface2endpoint_descriptor(iface, i);
		if (ed == NULL) {
			aprint_error_dev(self, "couldn't get ep %d\n", i);
			return;
		}
		if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
		    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
			sc->cue_ed[CUE_ENDPT_RX] = ed->bEndpointAddress;
		} else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
			   UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
			sc->cue_ed[CUE_ENDPT_TX] = ed->bEndpointAddress;
		} else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
			   UE_GET_XFERTYPE(ed->bmAttributes) == UE_INTERRUPT) {
			sc->cue_ed[CUE_ENDPT_INTR] = ed->bEndpointAddress;
		}
	}

#if 0
	/* Reset the adapter. */
	cue_reset(sc);
#endif
	/*
	 * Get station address.
	 */
	cue_getmac(sc, &eaddr);

	/*
	 * A CATC chip was detected. Inform the world.
	 */
	aprint_normal_dev(self, "Ethernet address %s\n", ether_sprintf(eaddr));

	/* Initialize interface info.*/
	ifp = GET_IFP(sc);
	ifp->if_softc = sc;
	ifp->if_mtu = ETHERMTU;
	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
	ifp->if_extflags = IFEF_START_MPSAFE;
	ifp->if_init = cue_init;
	ifp->if_ioctl = cue_ioctl;
	ifp->if_start = cue_start;
	ifp->if_watchdog = cue_watchdog;
	strlcpy(ifp->if_xname, device_xname(sc->cue_dev), IFNAMSIZ);

	IFQ_SET_READY(&ifp->if_snd);

	/* Attach the interface. */
	if_initialize(ifp);
	sc->cue_ipq = if_percpuq_create(&sc->cue_ec.ec_if);
	ether_ifattach(ifp, eaddr);
	if_register(ifp);
	ether_set_ifflags_cb(&sc->cue_ec, cue_ifflags_cb);
	rnd_attach_source(&sc->rnd_source, device_xname(sc->cue_dev),
	    RND_TYPE_NET, RND_FLAG_DEFAULT);

	callout_init(&(sc->cue_stat_ch), 0);

	sc->cue_attached = 1;

	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->cue_udev, sc->cue_dev);

	return;
}

int
cue_detach(device_t self, int flags)
{
	struct cue_softc *sc = device_private(self);
	struct ifnet		*ifp = GET_IFP(sc);
	int			s;

	DPRINTFN(2,("%s: %s: enter\n", device_xname(sc->cue_dev), __func__));

	callout_stop(&sc->cue_stat_ch);
	/*
	 * Remove any pending task.  It cannot be executing because it run
	 * in the same thread as detach.
	 */
	usb_rem_task(sc->cue_udev, &sc->cue_tick_task);
	usb_rem_task(sc->cue_udev, &sc->cue_stop_task);

	if (!sc->cue_attached) {
		/* Detached before attached finished, so just bail out. */
		return 0;
	}

	s = splusb();

	if (ifp->if_flags & IFF_RUNNING)
		cue_stop(sc);

	rnd_detach_source(&sc->rnd_source);
	ether_ifdetach(ifp);

	if_detach(ifp);

#ifdef DIAGNOSTIC
	if (sc->cue_ep[CUE_ENDPT_TX] != NULL ||
	    sc->cue_ep[CUE_ENDPT_RX] != NULL ||
	    sc->cue_ep[CUE_ENDPT_INTR] != NULL)
		aprint_debug_dev(self, "detach has active endpoints\n");
#endif

	mutex_destroy(&sc->cue_rxlock);
	mutex_destroy(&sc->cue_txlock);
	mutex_destroy(&sc->cue_lock);

	sc->cue_attached = 0;
	splx(s);

	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->cue_udev, sc->cue_dev);

	return 0;
}

int
cue_activate(device_t self, enum devact act)
{
	struct cue_softc *sc = device_private(self);

	DPRINTFN(2,("%s: %s: enter\n", device_xname(sc->cue_dev), __func__));

	switch (act) {
	case DVACT_DEACTIVATE:
		/* Deactivate the interface. */
		if_deactivate(&sc->cue_ec.ec_if);
		sc->cue_dying = 1;
		return 0;
	default:
		return EOPNOTSUPP;
	}
}

/*
 * Initialize an RX descriptor and attach an MBUF cluster.
 */
Static int
cue_newbuf(struct cue_softc *sc, struct cue_chain *c, struct mbuf *m)
{
	struct mbuf		*m_new = NULL;

	if (m == NULL) {
		MGETHDR(m_new, M_DONTWAIT, MT_DATA);
		if (m_new == NULL) {
			printf("%s: no memory for rx list "
			    "-- packet dropped!\n", device_xname(sc->cue_dev));
			return ENOBUFS;
		}

		MCLGET(m_new, M_DONTWAIT);
		if (!(m_new->m_flags & M_EXT)) {
			printf("%s: no memory for rx list "
			    "-- packet dropped!\n", device_xname(sc->cue_dev));
			m_freem(m_new);
			return ENOBUFS;
		}
		m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
	} else {
		m_new = m;
		m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
		m_new->m_data = m_new->m_ext.ext_buf;
	}

	m_adj(m_new, ETHER_ALIGN);
	c->cue_mbuf = m_new;

	return 0;
}

Static int
cue_rx_list_init(struct cue_softc *sc)
{
	struct cue_cdata	*cd;
	struct cue_chain	*c;
	int			i;

	cd = &sc->cue_cdata;
	for (i = 0; i < CUE_RX_LIST_CNT; i++) {
		c = &cd->cue_rx_chain[i];
		c->cue_sc = sc;
		c->cue_idx = i;
		if (cue_newbuf(sc, c, NULL) == ENOBUFS)
			return ENOBUFS;
		if (c->cue_xfer == NULL) {
			int error = usbd_create_xfer(sc->cue_ep[CUE_ENDPT_RX],
			    CUE_BUFSZ, USBD_SHORT_XFER_OK, 0, &c->cue_xfer);
			if (error)
				return error;
			c->cue_buf = usbd_get_buffer(c->cue_xfer);
		}
	}

	return 0;
}
#if 0
Static void
cue_rx_list_free(struct cue_softc *sc)
{
	/* Free RX resources. */
	for (int i = 0; i < CUE_RX_LIST_CNT; i++) {
		if (sc->cue_cdata.cue_rx_chain[i].cue_xfer != NULL) {
			usbd_destroy_xfer(sc->cue_cdata.cue_rx_chain[i].cue_xfer);
			sc->cue_cdata.cue_rx_chain[i].cue_xfer = NULL;
		}
	}
}
#endif
Static int
cue_tx_list_init(struct cue_softc *sc)
{
	struct cue_cdata	*cd;
	struct cue_chain	*c;
	int			i;

	cd = &sc->cue_cdata;
	for (i = 0; i < CUE_TX_LIST_CNT; i++) {
		c = &cd->cue_tx_chain[i];
		c->cue_sc = sc;
		c->cue_idx = i;
		c->cue_mbuf = NULL;
		if (c->cue_xfer == NULL) {
			int error = usbd_create_xfer(sc->cue_ep[CUE_ENDPT_TX],
			    CUE_BUFSZ, 0, 0, &c->cue_xfer);
			if (error)
				return error;
			c->cue_buf = usbd_get_buffer(c->cue_xfer);
		}
	}

	return 0;
}

Static void
cue_tx_list_free(struct cue_softc *sc)
{
	/* Free TX resources. */
	for (int i = 0; i < CUE_TX_LIST_CNT; i++) {
		if (sc->cue_cdata.cue_tx_chain[i].cue_mbuf != NULL) {
			m_freem(sc->cue_cdata.cue_tx_chain[i].cue_mbuf);
			sc->cue_cdata.cue_tx_chain[i].cue_mbuf = NULL;
		}
		if (sc->cue_cdata.cue_tx_chain[i].cue_xfer != NULL) {
			usbd_destroy_xfer(sc->cue_cdata.cue_tx_chain[i].cue_xfer);
			sc->cue_cdata.cue_tx_chain[i].cue_xfer = NULL;
		}
	}
}

/*
 * A frame has been uploaded: pass the resulting mbuf chain up to
 * the higher level protocols.
 */
Static void
cue_rxeof(struct usbd_xfer *xfer, void *priv, usbd_status status)
{
	struct cue_chain	*c = priv;
	struct cue_softc	*sc = c->cue_sc;
	struct ifnet		*ifp = GET_IFP(sc);
	struct mbuf		*m;
	int			total_len = 0;
	uint16_t		len;

	DPRINTFN(10,("%s: %s: enter status=%d\n", device_xname(sc->cue_dev),
		     __func__, status));

	if (sc->cue_dying)
		return;

	if (!(ifp->if_flags & IFF_RUNNING))
		return;

	if (status != USBD_NORMAL_COMPLETION) {
		if (status == USBD_NOT_STARTED || status == USBD_CANCELLED)
			return;
		sc->cue_rx_errs++;
		if (usbd_ratecheck(&sc->cue_rx_notice)) {
			printf("%s: %u usb errors on rx: %s\n",
			    device_xname(sc->cue_dev), sc->cue_rx_errs,
			    usbd_errstr(status));
			sc->cue_rx_errs = 0;
		}
		if (status == USBD_STALLED)
			usbd_clear_endpoint_stall_async(sc->cue_ep[CUE_ENDPT_RX]);
		goto done;
	}

	usbd_get_xfer_status(xfer, NULL, NULL, &total_len, NULL);

	memcpy(mtod(c->cue_mbuf, char *), c->cue_buf, total_len);

	m = c->cue_mbuf;
	len = UGETW(mtod(m, uint8_t *));

	/* No errors; receive the packet. */
	total_len = len;

	if (len < sizeof(struct ether_header)) {
		ifp->if_ierrors++;
		goto done;
	}

	m_adj(m, sizeof(uint16_t));
	m->m_pkthdr.len = m->m_len = total_len;

	m_set_rcvif(m, ifp);

	/* XXX ugly */
	if (cue_newbuf(sc, c, NULL) == ENOBUFS) {
		ifp->if_ierrors++;
		goto done;
	}

	DPRINTFN(10,("%s: %s: deliver %d\n", device_xname(sc->cue_dev),
		    __func__, m->m_len));
	if_percpuq_enqueue(sc->cue_ipq, m);

done:

	/* Setup new transfer. */
	usbd_setup_xfer(c->cue_xfer, c, c->cue_buf, CUE_BUFSZ,
	    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, cue_rxeof);
	usbd_transfer(c->cue_xfer);

	DPRINTFN(10,("%s: %s: start rx\n", device_xname(sc->cue_dev),
		    __func__));
}

/*
 * A frame was downloaded to the chip. It's safe for us to clean up
 * the list buffers.
 */
Static void
cue_txeof(struct usbd_xfer *xfer, void *priv,
    usbd_status status)
{
	struct cue_chain	*c = priv;
	struct cue_softc	*sc = c->cue_sc;
	struct ifnet		*ifp = GET_IFP(sc);
	int			s;

	if (sc->cue_dying)
		return;

	s = splnet();

	DPRINTFN(10,("%s: %s: enter status=%d\n", device_xname(sc->cue_dev),
		    __func__, status));

	ifp->if_timer = 0;
	ifp->if_flags &= ~IFF_OACTIVE;

	if (status != USBD_NORMAL_COMPLETION) {
		if (status == USBD_NOT_STARTED || status == USBD_CANCELLED) {
			splx(s);
			return;
		}
		ifp->if_oerrors++;
		printf("%s: usb error on tx: %s\n", device_xname(sc->cue_dev),
		    usbd_errstr(status));
		if (status == USBD_STALLED)
			usbd_clear_endpoint_stall_async(sc->cue_ep[CUE_ENDPT_TX]);
		splx(s);
		return;
	}

	ifp->if_opackets++;

	m_freem(c->cue_mbuf);
	c->cue_mbuf = NULL;

	if (IFQ_IS_EMPTY(&ifp->if_snd) == 0)
		cue_start(ifp);

	splx(s);
}

Static void
cue_tick(void *xsc)
{
	struct cue_softc	*sc = xsc;

	if (sc == NULL)
		return;

	if (sc->cue_dying)
		return;

	DPRINTFN(2,("%s: %s: enter\n", device_xname(sc->cue_dev), __func__));

	/* Perform statistics update in process context. */
	usb_add_task(sc->cue_udev, &sc->cue_tick_task, USB_TASKQ_DRIVER);
}

Static void
cue_tick_task(void *xsc)
{
	struct cue_softc	*sc = xsc;
	struct ifnet		*ifp;

	if (sc->cue_dying)
		return;

	DPRINTFN(2,("%s: %s: enter\n", device_xname(sc->cue_dev), __func__));

	ifp = GET_IFP(sc);

	ifp->if_collisions += cue_csr_read_2(sc, CUE_TX_SINGLECOLL);
	ifp->if_collisions += cue_csr_read_2(sc, CUE_TX_MULTICOLL);
	ifp->if_collisions += cue_csr_read_2(sc, CUE_TX_EXCESSCOLL);

	if (cue_csr_read_2(sc, CUE_RX_FRAMEERR))
		ifp->if_ierrors++;
}

Static int
cue_send(struct cue_softc *sc, struct mbuf *m, int idx)
{
	int			total_len;
	struct cue_chain	*c;
	usbd_status		err;

	c = &sc->cue_cdata.cue_tx_chain[idx];

	/*
	 * Copy the mbuf data into a contiguous buffer, leaving two
	 * bytes at the beginning to hold the frame length.
	 */
	m_copydata(m, 0, m->m_pkthdr.len, c->cue_buf + 2);
	c->cue_mbuf = m;

	total_len = m->m_pkthdr.len + 2;

	DPRINTFN(10,("%s: %s: total_len=%d\n",
		     device_xname(sc->cue_dev), __func__, total_len));

	/* The first two bytes are the frame length */
	c->cue_buf[0] = (uint8_t)m->m_pkthdr.len;
	c->cue_buf[1] = (uint8_t)(m->m_pkthdr.len >> 8);

	/* XXX 10000 */
	usbd_setup_xfer(c->cue_xfer, c, c->cue_buf, total_len, 0, 10000,
	    cue_txeof);

	/* Transmit */
	err = usbd_transfer(c->cue_xfer);
	if (err != USBD_IN_PROGRESS) {
		printf("%s: cue_send error=%s\n", device_xname(sc->cue_dev),
		       usbd_errstr(err));
		/* Stop the interface from process context. */
		usb_add_task(sc->cue_udev, &sc->cue_stop_task,
		    USB_TASKQ_DRIVER);
		return EIO;
	}

	sc->cue_cdata.cue_tx_cnt++;

	return 0;
}

Static void
cue_start(struct ifnet *ifp)
{
	struct cue_softc *sc = ifp->if_softc;
	KASSERT(ifp->if_extflags & IFEF_START_MPSAFE);

	mutex_enter(&sc->cue_txlock);
	cue_start_locked(ifp);
	mutex_exit(&sc->cue_txlock);
}

Static void
cue_start_locked(struct ifnet *ifp)
{
	struct cue_softc	*sc = ifp->if_softc;
	struct mbuf		*m_head = NULL;

	if (sc->cue_dying)
		return;

	DPRINTFN(10,("%s: %s: enter\n", device_xname(sc->cue_dev),__func__));

	if (ifp->if_flags & IFF_OACTIVE)
		return;

	IFQ_POLL(&ifp->if_snd, m_head);
	if (m_head == NULL)
		return;

	if (cue_send(sc, m_head, 0)) {
		ifp->if_flags |= IFF_OACTIVE;
		return;
	}

	IFQ_DEQUEUE(&ifp->if_snd, m_head);

	/*
	 * If there's a BPF listener, bounce a copy of this frame
	 * to him.
	 */
	bpf_mtap(ifp, m_head);

	ifp->if_flags |= IFF_OACTIVE;

	/*
	 * Set a timeout in case the chip goes out to lunch.
	 */
	ifp->if_timer = 5;
}

Static int
cue_init(struct ifnet *ifp)
{
	struct cue_softc *sc = ifp->if_softc;

	mutex_enter(&sc->cue_lock);
	int ret = cue_init_locked(ifp);
	mutex_exit(&sc->cue_lock);

	return ret;
}

Static int
cue_init_locked(struct ifnet *ifp)
{
	struct cue_softc	*sc = ifp->if_softc;
	int			i, ctl, err = 0;
	const u_char		*eaddr;

	if (sc->cue_dying)
		return EIO;

	DPRINTFN(10,("%s: %s: enter\n", device_xname(sc->cue_dev),__func__));

	if (ifp->if_flags & IFF_RUNNING)
		return 0;

	/*
	 * Cancel pending I/O and free all RX/TX buffers.
	 */
#if 1
	cue_reset(sc);
#endif

	/* Set advanced operation modes. */
	cue_csr_write_1(sc, CUE_ADVANCED_OPMODES,
	    CUE_AOP_EMBED_RXLEN | 0x03); /* 1 wait state */

	eaddr = CLLADDR(ifp->if_sadl);
	/* Set MAC address */
	for (i = 0; i < ETHER_ADDR_LEN; i++)
		cue_csr_write_1(sc, CUE_PAR0 - i, eaddr[i]);

	/* Enable RX logic. */
	ctl = CUE_ETHCTL_RX_ON | CUE_ETHCTL_MCAST_ON;
	if (ifp->if_flags & IFF_PROMISC)
		ctl |= CUE_ETHCTL_PROMISC;
	cue_csr_write_1(sc, CUE_ETHCTL, ctl);

	/* Load the multicast filter. */
	cue_setmulti(sc);

	/*
	 * Set the number of RX and TX buffers that we want
	 * to reserve inside the ASIC.
	 */
	cue_csr_write_1(sc, CUE_RX_BUFPKTS, CUE_RX_FRAMES);
	cue_csr_write_1(sc, CUE_TX_BUFPKTS, CUE_TX_FRAMES);

	/* Set advanced operation modes. */
	cue_csr_write_1(sc, CUE_ADVANCED_OPMODES,
	    CUE_AOP_EMBED_RXLEN | 0x01); /* 1 wait state */

	/* Program the LED operation. */
	cue_csr_write_1(sc, CUE_LEDCTL, CUE_LEDCTL_FOLLOW_LINK);

	if (sc->cue_ep[CUE_ENDPT_RX] == NULL) {
		/* Open RX and TX pipes. */
		err = usbd_open_pipe(sc->cue_iface, sc->cue_ed[CUE_ENDPT_RX],
		    USBD_EXCLUSIVE_USE, &sc->cue_ep[CUE_ENDPT_RX]);
		if (err) {
			printf("%s: open rx pipe failed: %s\n",
			device_xname(sc->cue_dev), usbd_errstr(err));
			goto fail;
		}
		err = usbd_open_pipe(sc->cue_iface, sc->cue_ed[CUE_ENDPT_TX],
		    USBD_EXCLUSIVE_USE, &sc->cue_ep[CUE_ENDPT_TX]);
		if (err) {
			printf("%s: open tx pipe failed: %s\n",
			device_xname(sc->cue_dev), usbd_errstr(err));
			goto fail1;
		}
	}
	/* Init TX ring. */
	if (cue_tx_list_init(sc)) {
		printf("%s: tx list init failed\n", device_xname(sc->cue_dev));
		goto fail2;
	}

	/* Init RX ring. */
	if (cue_rx_list_init(sc)) {
		printf("%s: rx list init failed\n", device_xname(sc->cue_dev));
		goto fail3;
	}

	/* Start up the receive pipe. */
	for (i = 0; i < CUE_RX_LIST_CNT; i++) {
		struct cue_chain *c = &sc->cue_cdata.cue_rx_chain[i];
		usbd_setup_xfer(c->cue_xfer, c, c->cue_buf, CUE_BUFSZ,
		    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, cue_rxeof);
		usbd_transfer(c->cue_xfer);
	}

	ifp->if_flags |= IFF_RUNNING;
	ifp->if_flags &= ~IFF_OACTIVE;

	callout_reset(&(sc->cue_stat_ch), (hz), (cue_tick), (sc));

	return 0;

fail3:
	cue_tx_list_free(sc);
fail2:
	usbd_close_pipe(sc->cue_ep[CUE_ENDPT_TX]);
fail1:
	usbd_close_pipe(sc->cue_ep[CUE_ENDPT_RX]);
fail:
	return EIO;
}

Static int
cue_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
	struct cue_softc	*sc = ifp->if_softc;
	int			s, error = 0;

	if (sc->cue_dying)
		return EIO;

	s = splnet();
	error = ether_ioctl(ifp, cmd, data);
	splx(s);

	if (error == ENETRESET) {
		error = 0;
		if (cmd == SIOCADDMULTI || cmd == SIOCDELMULTI) {
			mutex_enter(&sc->cue_lock);
			cue_setmulti(sc);
			mutex_exit(&sc->cue_lock);
		}
	}
	return error;
}

Static int
cue_ifflags_cb(struct ethercom *ec)
{
	struct ifnet *ifp = &ec->ec_if;
	struct cue_softc *sc = ifp->if_softc;
	int rc = 0;

	mutex_enter(&sc->cue_lock);

	int change = ifp->if_flags ^ sc->cue_if_flags;
	sc->cue_if_flags = ifp->if_flags;

	if ((change & ~(IFF_CANTCHANGE | IFF_DEBUG)) != 0) {
		rc = ENETRESET;
		goto out;
	}

	if ((change & IFF_PROMISC) != 0) {
		if (ifp->if_flags & IFF_PROMISC) {
			CUE_SETBIT(sc, CUE_ETHCTL, CUE_ETHCTL_PROMISC);
		} else if (!(ifp->if_flags & IFF_PROMISC)) {
			CUE_CLRBIT(sc, CUE_ETHCTL, CUE_ETHCTL_PROMISC);
		}
		cue_setmulti(sc);
	}

out:
	mutex_exit(&sc->cue_lock);

	return rc;
}

Static void
cue_watchdog(struct ifnet *ifp)
{
	struct cue_softc	*sc = ifp->if_softc;
	struct cue_chain	*c;
	usbd_status		stat;
	int			s;

	DPRINTFN(5,("%s: %s: enter\n", device_xname(sc->cue_dev), __func__));

	if (sc->cue_dying)
		return;

	ifp->if_oerrors++;
	printf("%s: watchdog timeout\n", device_xname(sc->cue_dev));

	s = splusb();
	c = &sc->cue_cdata.cue_tx_chain[0];
	usbd_get_xfer_status(c->cue_xfer, NULL, NULL, NULL, &stat);
	cue_txeof(c->cue_xfer, c, stat);

	if (IFQ_IS_EMPTY(&ifp->if_snd) == 0)
		cue_start(ifp);
	splx(s);
}

/*
 * Stop the adapter and free any mbufs allocated to the
 * RX and TX lists.
 */
Static void
cue_stop(struct cue_softc *sc)
{
	mutex_enter(&sc->cue_lock);
	cue_stop_locked(sc);
	mutex_exit(&sc->cue_lock);
}

Static void
cue_stop_locked(struct cue_softc *sc)
{
	usbd_status		err;
	struct ifnet		*ifp;

	DPRINTFN(10,("%s: %s: enter\n", device_xname(sc->cue_dev),__func__));

	ifp = GET_IFP(sc);
	ifp->if_timer = 0;

	cue_csr_write_1(sc, CUE_ETHCTL, 0);
	cue_reset(sc);
	callout_stop(&sc->cue_stat_ch);

	/* Stop transfers. */
	if (sc->cue_ep[CUE_ENDPT_RX] != NULL) {
		err = usbd_abort_pipe(sc->cue_ep[CUE_ENDPT_RX]);
		if (err) {
			printf("%s: abort rx pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
	}

	if (sc->cue_ep[CUE_ENDPT_TX] != NULL) {
		err = usbd_abort_pipe(sc->cue_ep[CUE_ENDPT_TX]);
		if (err) {
			printf("%s: abort tx pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
	}

	if (sc->cue_ep[CUE_ENDPT_INTR] != NULL) {
		err = usbd_abort_pipe(sc->cue_ep[CUE_ENDPT_INTR]);
		if (err) {
			printf("%s: abort intr pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
	}

	/* Stop transfers. */
	if (sc->cue_ep[CUE_ENDPT_RX] != NULL) {
		err = usbd_close_pipe(sc->cue_ep[CUE_ENDPT_RX]);
		if (err) {
			printf("%s: close rx pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
		sc->cue_ep[CUE_ENDPT_RX] = NULL;
	}

	if (sc->cue_ep[CUE_ENDPT_TX] != NULL) {
		err = usbd_close_pipe(sc->cue_ep[CUE_ENDPT_TX]);
		if (err) {
			printf("%s: close tx pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
		sc->cue_ep[CUE_ENDPT_TX] = NULL;
	}

	if (sc->cue_ep[CUE_ENDPT_INTR] != NULL) {
		err = usbd_close_pipe(sc->cue_ep[CUE_ENDPT_INTR]);
		if (err) {
			printf("%s: close intr pipe failed: %s\n",
			    device_xname(sc->cue_dev), usbd_errstr(err));
		}
		sc->cue_ep[CUE_ENDPT_INTR] = NULL;
	}

	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
}