freebsd-nq/sys/dev/usb2/ethernet/if_rue2.c

/*-
 * Copyright (c) 2001-2003, Shunsuke Akiyama <akiyama@FreeBSD.org>.
 * Copyright (c) 1997, 1998, 1999, 2000 Bill Paul <wpaul@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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR OR CONTRIBUTORS 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.
 */
/*-
 * Copyright (c) 1997, 1998, 1999, 2000
 *	Bill Paul <wpaul@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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

/*
 * RealTek RTL8150 USB to fast ethernet controller driver.
 * Datasheet is available from
 * ftp://ftp.realtek.com.tw/lancard/data_sheet/8150/.
 */

/*
 * NOTE: all function names beginning like "rue_cfg_" can only
 * be called from within the config thread function !
 */

#include <dev/usb2/include/usb2_devid.h>
#include <dev/usb2/include/usb2_standard.h>
#include <dev/usb2/include/usb2_mfunc.h>
#include <dev/usb2/include/usb2_error.h>

#define	usb2_config_td_cc usb2_ether_cc
#define	usb2_config_td_softc rue_softc

#define	USB_DEBUG_VAR rue_debug

#include <dev/usb2/core/usb2_core.h>
#include <dev/usb2/core/usb2_lookup.h>
#include <dev/usb2/core/usb2_process.h>
#include <dev/usb2/core/usb2_config_td.h>
#include <dev/usb2/core/usb2_debug.h>
#include <dev/usb2/core/usb2_request.h>
#include <dev/usb2/core/usb2_busdma.h>
#include <dev/usb2/core/usb2_util.h>

#include <dev/usb2/ethernet/usb2_ethernet.h>
#include <dev/usb2/ethernet/if_ruereg.h>

#if USB_DEBUG
static int rue_debug = 0;

SYSCTL_NODE(_hw_usb2, OID_AUTO, rue, CTLFLAG_RW, 0, "USB rue");
SYSCTL_INT(_hw_usb2_rue, OID_AUTO, debug, CTLFLAG_RW,
    &rue_debug, 0, "Debug level");
#endif

/*
 * Various supported device vendors/products.
 */

static const struct usb2_device_id rue_devs[] = {
	{USB_VPI(USB_VENDOR_MELCO, USB_PRODUCT_MELCO_LUAKTX, 0)},
	{USB_VPI(USB_VENDOR_REALTEK, USB_PRODUCT_REALTEK_USBKR100, 0)},
};

/* prototypes */

static device_probe_t rue_probe;
static device_attach_t rue_attach;
static device_detach_t rue_detach;
static device_shutdown_t rue_shutdown;

static usb2_callback_t rue_intr_clear_stall_callback;
static usb2_callback_t rue_intr_callback;
static usb2_callback_t rue_bulk_read_clear_stall_callback;
static usb2_callback_t rue_bulk_read_callback;
static usb2_callback_t rue_bulk_write_clear_stall_callback;
static usb2_callback_t rue_bulk_write_callback;

static usb2_config_td_command_t rue_config_copy;
static usb2_config_td_command_t rue_cfg_promisc_upd;
static usb2_config_td_command_t rue_cfg_first_time_setup;
static usb2_config_td_command_t rue_cfg_tick;
static usb2_config_td_command_t rue_cfg_pre_init;
static usb2_config_td_command_t rue_cfg_init;
static usb2_config_td_command_t rue_cfg_ifmedia_upd;
static usb2_config_td_command_t rue_cfg_pre_stop;
static usb2_config_td_command_t rue_cfg_stop;

static void rue_cfg_do_request(struct rue_softc *sc, struct usb2_device_request *req, void *data);
static void rue_cfg_read_mem(struct rue_softc *sc, uint16_t addr, void *buf, uint16_t len);
static void rue_cfg_write_mem(struct rue_softc *sc, uint16_t addr, void *buf, uint16_t len);
static uint8_t rue_cfg_csr_read_1(struct rue_softc *sc, uint16_t reg);
static uint16_t rue_cfg_csr_read_2(struct rue_softc *sc, uint16_t reg);
static void rue_cfg_csr_write_1(struct rue_softc *sc, uint16_t reg, uint8_t val);
static void rue_cfg_csr_write_2(struct rue_softc *sc, uint16_t reg, uint16_t val);
static void rue_cfg_csr_write_4(struct rue_softc *sc, int reg, uint32_t val);

static miibus_readreg_t rue_cfg_miibus_readreg;
static miibus_writereg_t rue_cfg_miibus_writereg;
static miibus_statchg_t rue_cfg_miibus_statchg;

static void rue_cfg_reset(struct rue_softc *sc);
static void rue_start_cb(struct ifnet *ifp);
static void rue_start_transfers(struct rue_softc *sc);
static void rue_init_cb(void *arg);
static int rue_ifmedia_upd_cb(struct ifnet *ifp);
static void rue_ifmedia_sts_cb(struct ifnet *ifp, struct ifmediareq *ifmr);
static int rue_ioctl_cb(struct ifnet *ifp, u_long command, caddr_t data);
static void rue_watchdog(void *arg);

static const struct usb2_config rue_config[RUE_N_TRANSFER] = {

	[RUE_BULK_DT_WR] = {
		.type = UE_BULK,
		.endpoint = UE_ADDR_ANY,
		.direction = UE_DIR_OUT,
		.mh.bufsize = MCLBYTES,
		.mh.flags = {.pipe_bof = 1,.force_short_xfer = 1,},
		.mh.callback = &rue_bulk_write_callback,
		.mh.timeout = 10000,	/* 10 seconds */
	},

	[RUE_BULK_DT_RD] = {
		.type = UE_BULK,
		.endpoint = UE_ADDR_ANY,
		.direction = UE_DIR_IN,
		.mh.bufsize = (MCLBYTES + 4),
		.mh.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
		.mh.callback = &rue_bulk_read_callback,
		.mh.timeout = 0,	/* no timeout */
	},

	[RUE_BULK_CS_WR] = {
		.type = UE_CONTROL,
		.endpoint = 0x00,	/* Control pipe */
		.direction = UE_DIR_ANY,
		.mh.bufsize = sizeof(struct usb2_device_request),
		.mh.flags = {},
		.mh.callback = &rue_bulk_write_clear_stall_callback,
		.mh.timeout = 1000,	/* 1 second */
		.mh.interval = 50,	/* 50ms */
	},

	[RUE_BULK_CS_RD] = {
		.type = UE_CONTROL,
		.endpoint = 0x00,	/* Control pipe */
		.direction = UE_DIR_ANY,
		.mh.bufsize = sizeof(struct usb2_device_request),
		.mh.flags = {},
		.mh.callback = &rue_bulk_read_clear_stall_callback,
		.mh.timeout = 1000,	/* 1 second */
		.mh.interval = 50,	/* 50ms */
	},

	[RUE_INTR_DT_RD] = {
		.type = UE_INTERRUPT,
		.endpoint = UE_ADDR_ANY,
		.direction = UE_DIR_IN,
		.mh.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
		.mh.bufsize = 0,	/* use wMaxPacketSize */
		.mh.callback = &rue_intr_callback,
	},

	[RUE_INTR_CS_RD] = {
		.type = UE_CONTROL,
		.endpoint = 0x00,	/* Control pipe */
		.direction = UE_DIR_ANY,
		.mh.bufsize = sizeof(struct usb2_device_request),
		.mh.flags = {},
		.mh.callback = &rue_intr_clear_stall_callback,
		.mh.timeout = 1000,	/* 1 second */
		.mh.interval = 50,	/* 50ms */
	},
};

static device_method_t rue_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe, rue_probe),
	DEVMETHOD(device_attach, rue_attach),
	DEVMETHOD(device_detach, rue_detach),
	DEVMETHOD(device_shutdown, rue_shutdown),

	/* Bus interface */
	DEVMETHOD(bus_print_child, bus_generic_print_child),
	DEVMETHOD(bus_driver_added, bus_generic_driver_added),

	/* MII interface */
	DEVMETHOD(miibus_readreg, rue_cfg_miibus_readreg),
	DEVMETHOD(miibus_writereg, rue_cfg_miibus_writereg),
	DEVMETHOD(miibus_statchg, rue_cfg_miibus_statchg),

	{0, 0}
};

static driver_t rue_driver = {
	.name = "rue",
	.methods = rue_methods,
	.size = sizeof(struct rue_softc),
};

static devclass_t rue_devclass;

DRIVER_MODULE(rue, ushub, rue_driver, rue_devclass, NULL, 0);
DRIVER_MODULE(miibus, rue, miibus_driver, miibus_devclass, 0, 0);
MODULE_DEPEND(rue, usb2_ethernet, 1, 1, 1);
MODULE_DEPEND(rue, usb2_core, 1, 1, 1);
MODULE_DEPEND(rue, ether, 1, 1, 1);
MODULE_DEPEND(rue, miibus, 1, 1, 1);

static void
rue_cfg_do_request(struct rue_softc *sc, struct usb2_device_request *req,
    void *data)
{
	uint16_t length;
	usb2_error_t err;

	if (usb2_config_td_is_gone(&sc->sc_config_td)) {
		goto error;
	}
	err = usb2_do_request_flags
	    (sc->sc_udev, &sc->sc_mtx, req, data, 0, NULL, 1000);

	if (err) {

		DPRINTF("device request failed, err=%s "
		    "(ignored)\n", usb2_errstr(err));

error:
		length = UGETW(req->wLength);

		if ((req->bmRequestType & UT_READ) && length) {
			bzero(data, length);
		}
	}
}

#define	RUE_CFG_SETBIT(sc, reg, x) \
	rue_cfg_csr_write_1(sc, reg, rue_cfg_csr_read_1(sc, reg) | (x))

#define	RUE_CFG_CLRBIT(sc, reg, x) \
	rue_cfg_csr_write_1(sc, reg, rue_cfg_csr_read_1(sc, reg) & ~(x))

static void
rue_cfg_read_mem(struct rue_softc *sc, uint16_t addr, void *buf,
    uint16_t len)
{
	struct usb2_device_request req;

	req.bmRequestType = UT_READ_VENDOR_DEVICE;
	req.bRequest = UR_SET_ADDRESS;
	USETW(req.wValue, addr);
	USETW(req.wIndex, 0);
	USETW(req.wLength, len);

	rue_cfg_do_request(sc, &req, buf);
}

static void
rue_cfg_write_mem(struct rue_softc *sc, uint16_t addr, void *buf,
    uint16_t len)
{
	struct usb2_device_request req;

	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = UR_SET_ADDRESS;
	USETW(req.wValue, addr);
	USETW(req.wIndex, 0);
	USETW(req.wLength, len);

	rue_cfg_do_request(sc, &req, buf);
}

static uint8_t
rue_cfg_csr_read_1(struct rue_softc *sc, uint16_t reg)
{
	uint8_t val;

	rue_cfg_read_mem(sc, reg, &val, 1);
	return (val);
}

static uint16_t
rue_cfg_csr_read_2(struct rue_softc *sc, uint16_t reg)
{
	uint8_t val[2];

	rue_cfg_read_mem(sc, reg, &val, 2);
	return (UGETW(val));
}

static void
rue_cfg_csr_write_1(struct rue_softc *sc, uint16_t reg, uint8_t val)
{
	rue_cfg_write_mem(sc, reg, &val, 1);
}

static void
rue_cfg_csr_write_2(struct rue_softc *sc, uint16_t reg, uint16_t val)
{
	uint8_t temp[2];

	USETW(temp, val);
	rue_cfg_write_mem(sc, reg, &temp, 2);
}

static void
rue_cfg_csr_write_4(struct rue_softc *sc, int reg, uint32_t val)
{
	uint8_t temp[4];

	USETDW(temp, val);
	rue_cfg_write_mem(sc, reg, &temp, 4);
}

static int
rue_cfg_miibus_readreg(device_t dev, int phy, int reg)
{
	struct rue_softc *sc = device_get_softc(dev);
	uint16_t rval;
	uint16_t ruereg;
	uint8_t do_unlock;

	if (phy != 0) {			/* RTL8150 supports PHY == 0, only */
		return (0);
	}
	/* avoid recursive locking */
	if (mtx_owned(&sc->sc_mtx)) {
		do_unlock = 0;
	} else {
		mtx_lock(&sc->sc_mtx);
		do_unlock = 1;
	}

	switch (reg) {
	case MII_BMCR:
		ruereg = RUE_BMCR;
		break;
	case MII_BMSR:
		ruereg = RUE_BMSR;
		break;
	case MII_ANAR:
		ruereg = RUE_ANAR;
		break;
	case MII_ANER:
		ruereg = RUE_AER;
		break;
	case MII_ANLPAR:
		ruereg = RUE_ANLP;
		break;
	case MII_PHYIDR1:
	case MII_PHYIDR2:
		rval = 0;
		goto done;
	default:
		if ((RUE_REG_MIN <= reg) && (reg <= RUE_REG_MAX)) {
			rval = rue_cfg_csr_read_1(sc, reg);
			goto done;
		}
		printf("rue%d: bad phy register\n", sc->sc_unit);
		rval = 0;
		goto done;
	}

	rval = rue_cfg_csr_read_2(sc, ruereg);
done:
	if (do_unlock) {
		mtx_unlock(&sc->sc_mtx);
	}
	return (rval);
}

static int
rue_cfg_miibus_writereg(device_t dev, int phy, int reg, int data)
{
	struct rue_softc *sc = device_get_softc(dev);
	uint16_t ruereg;
	uint8_t do_unlock;

	if (phy != 0) {			/* RTL8150 supports PHY == 0, only */
		return (0);
	}
	/* avoid recursive locking */
	if (mtx_owned(&sc->sc_mtx)) {
		do_unlock = 0;
	} else {
		mtx_lock(&sc->sc_mtx);
		do_unlock = 1;
	}

	switch (reg) {
	case MII_BMCR:
		ruereg = RUE_BMCR;
		break;
	case MII_BMSR:
		ruereg = RUE_BMSR;
		break;
	case MII_ANAR:
		ruereg = RUE_ANAR;
		break;
	case MII_ANER:
		ruereg = RUE_AER;
		break;
	case MII_ANLPAR:
		ruereg = RUE_ANLP;
		break;
	case MII_PHYIDR1:
	case MII_PHYIDR2:
		goto done;
	default:
		if ((RUE_REG_MIN <= reg) && (reg <= RUE_REG_MAX)) {
			rue_cfg_csr_write_1(sc, reg, data);
			goto done;
		}
		printf("%s: bad phy register\n",
		    sc->sc_name);
		goto done;
	}
	rue_cfg_csr_write_2(sc, ruereg, data);
done:
	if (do_unlock) {
		mtx_unlock(&sc->sc_mtx);
	}
	return (0);
}

static void
rue_cfg_miibus_statchg(device_t dev)
{
	/*
	 * When the code below is enabled the card starts doing weird
	 * things after link going from UP to DOWN and back UP.
	 *
	 * Looks like some of register writes below messes up PHY
	 * interface.
	 *
	 * No visible regressions were found after commenting this code
	 * out, so that disable it for good.
	 */
#if 0
	struct rue_softc *sc = device_get_softc(dev);
	struct mii_data *mii = GET_MII(sc);
	uint16_t bmcr;
	uint8_t do_unlock;

	/* avoid recursive locking */
	if (mtx_owned(&sc->sc_mtx)) {
		do_unlock = 0;
	} else {
		mtx_lock(&sc->sc_mtx);
		do_unlock = 1;
	}

	RUE_CFG_CLRBIT(sc, RUE_CR, (RUE_CR_RE | RUE_CR_TE));

	bmcr = rue_cfg_csr_read_2(sc, RUE_BMCR);

	if (IFM_SUBTYPE(mii->mii_media_active) == IFM_100_TX)
		bmcr |= RUE_BMCR_SPD_SET;
	else
		bmcr &= ~RUE_BMCR_SPD_SET;

	if ((mii->mii_media_active & IFM_GMASK) == IFM_FDX)
		bmcr |= RUE_BMCR_DUPLEX;
	else
		bmcr &= ~RUE_BMCR_DUPLEX;

	rue_cfg_csr_write_2(sc, RUE_BMCR, bmcr);

	RUE_CFG_SETBIT(sc, RUE_CR, (RUE_CR_RE | RUE_CR_TE));

	if (do_unlock) {
		mtx_unlock(&sc->sc_mtx);
	}
#endif
}

static void
rue_mchash(struct usb2_config_td_cc *cc, const uint8_t *ptr)
{
	uint8_t h;

	h = ether_crc32_be(ptr, ETHER_ADDR_LEN) >> 26;
	cc->if_hash[h / 8] |= 1 << (h & 7);
	cc->if_nhash = 1;
}

static void
rue_config_copy(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	bzero(cc, sizeof(*cc));
	usb2_ether_cc(sc->sc_ifp, &rue_mchash, cc);
}

/*
 * Program the 64-bit multicast hash filter.
 */
static void
rue_cfg_promisc_upd(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	uint16_t rxcfg;

	rxcfg = rue_cfg_csr_read_2(sc, RUE_RCR);

	if ((cc->if_flags & IFF_ALLMULTI) ||
	    (cc->if_flags & IFF_PROMISC)) {
		rxcfg |= (RUE_RCR_AAM | RUE_RCR_AAP);
		rxcfg &= ~RUE_RCR_AM;
		rue_cfg_csr_write_2(sc, RUE_RCR, rxcfg);
		rue_cfg_csr_write_4(sc, RUE_MAR0, 0xFFFFFFFF);
		rue_cfg_csr_write_4(sc, RUE_MAR4, 0xFFFFFFFF);
		return;
	}
	/* first, zero all the existing hash bits */
	rue_cfg_csr_write_4(sc, RUE_MAR0, 0);
	rue_cfg_csr_write_4(sc, RUE_MAR4, 0);

	if (cc->if_nhash)
		rxcfg |= RUE_RCR_AM;
	else
		rxcfg &= ~RUE_RCR_AM;

	rxcfg &= ~(RUE_RCR_AAM | RUE_RCR_AAP);

	rue_cfg_csr_write_2(sc, RUE_RCR, rxcfg);
	rue_cfg_write_mem(sc, RUE_MAR0, cc->if_hash, 4);
	rue_cfg_write_mem(sc, RUE_MAR4, cc->if_hash + 4, 4);
}

static void
rue_cfg_reset(struct rue_softc *sc)
{
	usb2_error_t err;
	uint16_t to;

	rue_cfg_csr_write_1(sc, RUE_CR, RUE_CR_SOFT_RST);

	for (to = 0;; to++) {

		if (to < RUE_TIMEOUT) {

			err = usb2_config_td_sleep(&sc->sc_config_td, hz / 100);

			if (err) {
				break;
			}
			if (!(rue_cfg_csr_read_1(sc, RUE_CR) & RUE_CR_SOFT_RST)) {
				break;
			}
		} else {
			printf("%s: reset timeout!\n",
			    sc->sc_name);
			break;
		}
	}

	err = usb2_config_td_sleep(&sc->sc_config_td, hz / 100);
}

/*
 * Probe for a RTL8150 chip.
 */
static int
rue_probe(device_t dev)
{
	struct usb2_attach_arg *uaa = device_get_ivars(dev);

	if (uaa->usb2_mode != USB_MODE_HOST) {
		return (ENXIO);
	}
	if (uaa->info.bConfigIndex != RUE_CONFIG_IDX) {
		return (ENXIO);
	}
	if (uaa->info.bIfaceIndex != RUE_IFACE_IDX) {
		return (ENXIO);
	}
	return (usb2_lookup_id_by_uaa(rue_devs, sizeof(rue_devs), uaa));
}

/*
 * Attach the interface. Allocate softc structures, do ifmedia
 * setup and ethernet/BPF attach.
 */
static int
rue_attach(device_t dev)
{
	struct usb2_attach_arg *uaa = device_get_ivars(dev);
	struct rue_softc *sc = device_get_softc(dev);
	int32_t error;
	uint8_t iface_index;

	sc->sc_udev = uaa->device;
	sc->sc_dev = dev;
	sc->sc_unit = device_get_unit(dev);

	device_set_usb2_desc(dev);

	snprintf(sc->sc_name, sizeof(sc->sc_name), "%s",
	    device_get_nameunit(dev));

	mtx_init(&sc->sc_mtx, "rue lock", NULL, MTX_DEF | MTX_RECURSE);

	usb2_callout_init_mtx(&sc->sc_watchdog, &sc->sc_mtx, 0);

	iface_index = RUE_IFACE_IDX;
	error = usb2_transfer_setup(uaa->device, &iface_index,
	    sc->sc_xfer, rue_config, RUE_N_TRANSFER,
	    sc, &sc->sc_mtx);
	if (error) {
		device_printf(dev, "allocating USB "
		    "transfers failed!\n");
		goto detach;
	}
	error = usb2_config_td_setup(&sc->sc_config_td, sc, &sc->sc_mtx,
	    NULL, sizeof(struct usb2_config_td_cc), 16);
	if (error) {
		device_printf(dev, "could not setup config "
		    "thread!\n");
		goto detach;
	}
	mtx_lock(&sc->sc_mtx);

	sc->sc_flags |= RUE_FLAG_WAIT_LINK;

	/* start setup */

	usb2_config_td_queue_command
	    (&sc->sc_config_td, NULL, &rue_cfg_first_time_setup, 0, 0);

	rue_watchdog(sc);
	mtx_unlock(&sc->sc_mtx);
	return (0);			/* success */

detach:
	rue_detach(dev);
	return (ENXIO);			/* failure */
}

static void
rue_cfg_first_time_setup(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct ifnet *ifp;
	int error;
	uint8_t eaddr[min(ETHER_ADDR_LEN, 6)];

	/* reset the adapter */
	rue_cfg_reset(sc);

	/* get station address from the EEPROM */
	rue_cfg_read_mem(sc, RUE_EEPROM_IDR0,
	    eaddr, ETHER_ADDR_LEN);

	mtx_unlock(&sc->sc_mtx);

	ifp = if_alloc(IFT_ETHER);

	mtx_lock(&sc->sc_mtx);

	if (ifp == NULL) {
		printf("%s: could not if_alloc()\n",
		    sc->sc_name);
		goto done;
	}

	ifp->if_softc = sc;
	if_initname(ifp, "rue", sc->sc_unit);
	ifp->if_mtu = ETHERMTU;
	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
	ifp->if_ioctl = rue_ioctl_cb;
	ifp->if_start = rue_start_cb;
	ifp->if_watchdog = NULL;
	ifp->if_init = rue_init_cb;
	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
	ifp->if_snd.ifq_drv_maxlen = IFQ_MAXLEN;
	IFQ_SET_READY(&ifp->if_snd);

	/*
	 * XXX need Giant when accessing the device structures !
	 */

	mtx_unlock(&sc->sc_mtx);

	mtx_lock(&Giant);

	/* MII setup */
	error = mii_phy_probe(sc->sc_dev, &sc->sc_miibus,
	    &rue_ifmedia_upd_cb,
	    &rue_ifmedia_sts_cb);
	mtx_unlock(&Giant);

	mtx_lock(&sc->sc_mtx);

	if (error) {
		printf("%s: MII without any PHY!\n",
		    sc->sc_name);
		if_free(ifp);
		goto done;
	}
	sc->sc_ifp = ifp;

	mtx_unlock(&sc->sc_mtx);

	/*
	 * Call MI attach routine.
	 */

	ether_ifattach(ifp, eaddr);

	mtx_lock(&sc->sc_mtx);

done:
	return;
}

static int
rue_detach(device_t dev)
{
	struct rue_softc *sc = device_get_softc(dev);
	struct ifnet *ifp;

	usb2_config_td_drain(&sc->sc_config_td);

	mtx_lock(&sc->sc_mtx);

	usb2_callout_stop(&sc->sc_watchdog);

	rue_cfg_pre_stop(sc, NULL, 0);

	ifp = sc->sc_ifp;

	mtx_unlock(&sc->sc_mtx);

	/* stop all USB transfers first */
	usb2_transfer_unsetup(sc->sc_xfer, RUE_N_TRANSFER);

	/* get rid of any late children */
	bus_generic_detach(dev);

	if (ifp) {
		ether_ifdetach(ifp);
		if_free(ifp);
	}
	usb2_config_td_unsetup(&sc->sc_config_td);

	usb2_callout_drain(&sc->sc_watchdog);

	mtx_destroy(&sc->sc_mtx);

	return (0);
}

static void
rue_intr_clear_stall_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct usb2_xfer *xfer_other = sc->sc_xfer[RUE_INTR_DT_RD];

	if (usb2_clear_stall_callback(xfer, xfer_other)) {
		DPRINTF("stall cleared\n");
		sc->sc_flags &= ~RUE_FLAG_INTR_STALL;
		usb2_transfer_start(xfer_other);
	}
}

static void
rue_intr_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct ifnet *ifp = sc->sc_ifp;
	struct rue_intrpkt pkt;

	switch (USB_GET_STATE(xfer)) {
	case USB_ST_TRANSFERRED:

		if (ifp && (ifp->if_drv_flags & IFF_DRV_RUNNING) &&
		    (xfer->actlen >= sizeof(pkt))) {

			usb2_copy_out(xfer->frbuffers, 0, &pkt, sizeof(pkt));

			ifp->if_ierrors += pkt.rue_rxlost_cnt;
			ifp->if_ierrors += pkt.rue_crcerr_cnt;
			ifp->if_collisions += pkt.rue_col_cnt;
		}
	case USB_ST_SETUP:
		if (sc->sc_flags & RUE_FLAG_INTR_STALL) {
			usb2_transfer_start(sc->sc_xfer[RUE_INTR_CS_RD]);
		} else {
			xfer->frlengths[0] = xfer->max_data_length;
			usb2_start_hardware(xfer);
		}
		return;

	default:			/* Error */
		if (xfer->error != USB_ERR_CANCELLED) {
			/* start clear stall */
			sc->sc_flags |= RUE_FLAG_INTR_STALL;
			usb2_transfer_start(sc->sc_xfer[RUE_INTR_CS_RD]);
		}
		return;
	}
}

static void
rue_bulk_read_clear_stall_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct usb2_xfer *xfer_other = sc->sc_xfer[RUE_BULK_DT_RD];

	if (usb2_clear_stall_callback(xfer, xfer_other)) {
		DPRINTF("stall cleared\n");
		sc->sc_flags &= ~RUE_FLAG_READ_STALL;
		usb2_transfer_start(xfer_other);
	}
}

static void
rue_bulk_read_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct ifnet *ifp = sc->sc_ifp;
	uint16_t status;
	struct mbuf *m = NULL;

	switch (USB_GET_STATE(xfer)) {
	case USB_ST_TRANSFERRED:

		if (xfer->actlen < 4) {
			ifp->if_ierrors++;
			goto tr_setup;
		}
		usb2_copy_out(xfer->frbuffers, xfer->actlen - 4,
		    &status, sizeof(status));

		status = le16toh(status);

		/* check recieve packet was valid or not */

		if ((status & RUE_RXSTAT_VALID) == 0) {
			ifp->if_ierrors++;
			goto tr_setup;
		}
		xfer->actlen -= 4;

		if (xfer->actlen < sizeof(struct ether_header)) {
			ifp->if_ierrors++;
			goto tr_setup;
		}
		m = usb2_ether_get_mbuf();

		if (m == NULL) {
			ifp->if_ierrors++;
			goto tr_setup;
		}
		xfer->actlen = min(xfer->actlen, m->m_len);

		usb2_copy_out(xfer->frbuffers, 0, m->m_data, xfer->actlen);

		ifp->if_ipackets++;
		m->m_pkthdr.rcvif = ifp;
		m->m_pkthdr.len = m->m_len = xfer->actlen;

	case USB_ST_SETUP:
tr_setup:

		if (sc->sc_flags & RUE_FLAG_READ_STALL) {
			usb2_transfer_start(sc->sc_xfer[RUE_BULK_CS_RD]);
		} else {
			xfer->frlengths[0] = xfer->max_data_length;
			usb2_start_hardware(xfer);
		}

		/*
		 * At the end of a USB callback it is always safe to unlock
		 * the private mutex of a device! That is why we do the
		 * "if_input" here, and not some lines up!
		 */
		if (m) {
			mtx_unlock(&sc->sc_mtx);
			(ifp->if_input) (ifp, m);
			mtx_lock(&sc->sc_mtx);
		}
		return;

	default:			/* Error */
		if (xfer->error != USB_ERR_CANCELLED) {
			/* try to clear stall first */
			sc->sc_flags |= RUE_FLAG_READ_STALL;
			usb2_transfer_start(sc->sc_xfer[RUE_BULK_CS_RD]);
		}
		DPRINTF("bulk read error, %s\n",
		    usb2_errstr(xfer->error));
		return;

	}
}

static void
rue_bulk_write_clear_stall_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct usb2_xfer *xfer_other = sc->sc_xfer[RUE_BULK_DT_WR];

	if (usb2_clear_stall_callback(xfer, xfer_other)) {
		DPRINTF("stall cleared\n");
		sc->sc_flags &= ~RUE_FLAG_WRITE_STALL;
		usb2_transfer_start(xfer_other);
	}
}

static void
rue_bulk_write_callback(struct usb2_xfer *xfer)
{
	struct rue_softc *sc = xfer->priv_sc;
	struct ifnet *ifp = sc->sc_ifp;
	struct mbuf *m;
	uint32_t temp_len;

	switch (USB_GET_STATE(xfer)) {
	case USB_ST_TRANSFERRED:
		DPRINTFN(11, "transfer complete\n");

		ifp->if_opackets++;

	case USB_ST_SETUP:

		if (sc->sc_flags & RUE_FLAG_WRITE_STALL) {
			usb2_transfer_start(sc->sc_xfer[RUE_BULK_CS_WR]);
			goto done;
		}
		if (sc->sc_flags & RUE_FLAG_WAIT_LINK) {
			/*
			 * don't send anything if there is no link !
			 */
			goto done;
		}
		IFQ_DRV_DEQUEUE(&ifp->if_snd, m);

		if (m == NULL) {
			goto done;
		}
		if (m->m_pkthdr.len > MCLBYTES) {
			m->m_pkthdr.len = MCLBYTES;
		}
		temp_len = m->m_pkthdr.len;

		usb2_m_copy_in(xfer->frbuffers, 0,
		    m, 0, m->m_pkthdr.len);

		/*
		 * This is an undocumented behavior.
		 * RTL8150 chip doesn't send frame length smaller than
		 * RUE_MIN_FRAMELEN (60) byte packet.
		 */
		if (temp_len < RUE_MIN_FRAMELEN) {
			usb2_bzero(xfer->frbuffers, temp_len,
			    RUE_MIN_FRAMELEN - temp_len);
			temp_len = RUE_MIN_FRAMELEN;
		}
		xfer->frlengths[0] = temp_len;

		/*
		 * if there's a BPF listener, bounce a copy
		 * of this frame to him:
		 */
		BPF_MTAP(ifp, m);

		m_freem(m);

		usb2_start_hardware(xfer);

done:
		return;

	default:			/* Error */
		DPRINTFN(11, "transfer error, %s\n",
		    usb2_errstr(xfer->error));

		if (xfer->error != USB_ERR_CANCELLED) {
			/* try to clear stall first */
			sc->sc_flags |= RUE_FLAG_WRITE_STALL;
			usb2_transfer_start(sc->sc_xfer[RUE_BULK_CS_WR]);
		}
		ifp->if_oerrors++;
		return;

	}
}

static void
rue_cfg_tick(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct mii_data *mii = GET_MII(sc);

	if ((ifp == NULL) ||
	    (mii == NULL)) {
		/* not ready */
		return;
	}
	mii_tick(mii);

	mii_pollstat(mii);

	if ((sc->sc_flags & RUE_FLAG_WAIT_LINK) &&
	    (mii->mii_media_status & IFM_ACTIVE) &&
	    (IFM_SUBTYPE(mii->mii_media_active) != IFM_NONE)) {
		sc->sc_flags &= ~RUE_FLAG_WAIT_LINK;
	}
	sc->sc_media_active = mii->mii_media_active;
	sc->sc_media_status = mii->mii_media_status;

	/* start stopped transfers, if any */

	rue_start_transfers(sc);
}

static void
rue_start_cb(struct ifnet *ifp)
{
	struct rue_softc *sc = ifp->if_softc;

	mtx_lock(&sc->sc_mtx);

	rue_start_transfers(sc);

	mtx_unlock(&sc->sc_mtx);
}

static void
rue_start_transfers(struct rue_softc *sc)
{
	if ((sc->sc_flags & RUE_FLAG_LL_READY) &&
	    (sc->sc_flags & RUE_FLAG_HL_READY)) {

		/*
		 * start the USB transfers, if not already started:
		 */
		usb2_transfer_start(sc->sc_xfer[RUE_INTR_DT_RD]);
		usb2_transfer_start(sc->sc_xfer[RUE_BULK_DT_RD]);
		usb2_transfer_start(sc->sc_xfer[RUE_BULK_DT_WR]);
	}
}

static void
rue_init_cb(void *arg)
{
	struct rue_softc *sc = arg;

	mtx_lock(&sc->sc_mtx);
	usb2_config_td_queue_command
	    (&sc->sc_config_td, &rue_cfg_pre_init,
	    &rue_cfg_init, 0, 0);
	mtx_unlock(&sc->sc_mtx);
}

static void
rue_cfg_pre_init(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct ifnet *ifp = sc->sc_ifp;

	/* immediate configuration */

	rue_cfg_pre_stop(sc, cc, 0);

	ifp->if_drv_flags |= IFF_DRV_RUNNING;

	sc->sc_flags |= RUE_FLAG_HL_READY;
}

static void
rue_cfg_init(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct mii_data *mii = GET_MII(sc);
	uint16_t rxcfg;

	/*
	 * Cancel pending I/O
	 */

	rue_cfg_stop(sc, cc, 0);

	/* set MAC address */

	rue_cfg_write_mem(sc, RUE_IDR0, cc->if_lladdr, ETHER_ADDR_LEN);

	/*
	 * Set the initial TX and RX configuration.
	 */
	rue_cfg_csr_write_1(sc, RUE_TCR, RUE_TCR_CONFIG);

	rxcfg = RUE_RCR_CONFIG;

	/* Set capture broadcast bit to capture broadcast frames. */
	if (cc->if_flags & IFF_BROADCAST)
		rxcfg |= RUE_RCR_AB;
	else
		rxcfg &= ~RUE_RCR_AB;

	rue_cfg_csr_write_2(sc, RUE_RCR, rxcfg);

	/* Load the multicast filter */
	rue_cfg_promisc_upd(sc, cc, 0);

	/* Enable RX and TX */
	rue_cfg_csr_write_1(sc, RUE_CR, (RUE_CR_TE | RUE_CR_RE | RUE_CR_EP3CLREN));

	mii_mediachg(mii);

	sc->sc_flags |= (RUE_FLAG_READ_STALL |
	    RUE_FLAG_WRITE_STALL |
	    RUE_FLAG_LL_READY);

	rue_start_transfers(sc);
}

/*
 * Set media options.
 */
static int
rue_ifmedia_upd_cb(struct ifnet *ifp)
{
	struct rue_softc *sc = ifp->if_softc;

	mtx_lock(&sc->sc_mtx);
	usb2_config_td_queue_command
	    (&sc->sc_config_td, NULL,
	    &rue_cfg_ifmedia_upd, 0, 0);
	mtx_unlock(&sc->sc_mtx);

	return (0);
}

static void
rue_cfg_ifmedia_upd(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct mii_data *mii = GET_MII(sc);

	if ((ifp == NULL) ||
	    (mii == NULL)) {
		/* not ready */
		return;
	}
	sc->sc_flags |= RUE_FLAG_WAIT_LINK;

	if (mii->mii_instance) {
		struct mii_softc *miisc;

		LIST_FOREACH(miisc, &mii->mii_phys, mii_list) {
			mii_phy_reset(miisc);
		}
	}
	mii_mediachg(mii);
}

/*
 * Report current media status.
 */
static void
rue_ifmedia_sts_cb(struct ifnet *ifp, struct ifmediareq *ifmr)
{
	struct rue_softc *sc = ifp->if_softc;

	mtx_lock(&sc->sc_mtx);

	ifmr->ifm_active = sc->sc_media_active;
	ifmr->ifm_status = sc->sc_media_status;

	mtx_unlock(&sc->sc_mtx);
}

static int
rue_ioctl_cb(struct ifnet *ifp, u_long command, caddr_t data)
{
	struct rue_softc *sc = ifp->if_softc;
	struct mii_data *mii;
	int error = 0;

	switch (command) {
	case SIOCSIFFLAGS:

		mtx_lock(&sc->sc_mtx);
		if (ifp->if_flags & IFF_UP) {
			if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
				usb2_config_td_queue_command
				    (&sc->sc_config_td, &rue_config_copy,
				    &rue_cfg_promisc_upd, 0, 0);
			} else {
				usb2_config_td_queue_command
				    (&sc->sc_config_td, &rue_cfg_pre_init,
				    &rue_cfg_init, 0, 0);
			}
		} else {
			if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
				usb2_config_td_queue_command
				    (&sc->sc_config_td, &rue_cfg_pre_stop,
				    &rue_cfg_stop, 0, 0);
			}
		}
		mtx_unlock(&sc->sc_mtx);
		break;

	case SIOCADDMULTI:
	case SIOCDELMULTI:
		mtx_lock(&sc->sc_mtx);
		usb2_config_td_queue_command
		    (&sc->sc_config_td, &rue_config_copy,
		    &rue_cfg_promisc_upd, 0, 0);
		mtx_unlock(&sc->sc_mtx);
		break;

	case SIOCGIFMEDIA:
	case SIOCSIFMEDIA:
		mii = GET_MII(sc);
		if (mii == NULL) {
			error = EINVAL;
		} else {
			error = ifmedia_ioctl
			    (ifp, (void *)data, &mii->mii_media, command);
		}
		break;

	default:
		error = ether_ioctl(ifp, command, data);
		break;
	}
	return (error);
}

static void
rue_watchdog(void *arg)
{
	struct rue_softc *sc = arg;

	mtx_assert(&sc->sc_mtx, MA_OWNED);

	usb2_config_td_queue_command
	    (&sc->sc_config_td, NULL, &rue_cfg_tick, 0, 0);

	usb2_callout_reset(&sc->sc_watchdog,
	    hz, &rue_watchdog, sc);
}

/*
 * NOTE: can be called when "ifp" is NULL
 */
static void
rue_cfg_pre_stop(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	struct ifnet *ifp = sc->sc_ifp;

	if (cc) {
		/* copy the needed configuration */
		rue_config_copy(sc, cc, refcount);
	}
	/* immediate configuration */

	if (ifp) {
		/* clear flags */
		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
	}
	sc->sc_flags &= ~(RUE_FLAG_HL_READY |
	    RUE_FLAG_LL_READY);

	sc->sc_flags |= RUE_FLAG_WAIT_LINK;

	/*
	 * stop all the transfers, if not already stopped:
	 */
	usb2_transfer_stop(sc->sc_xfer[RUE_BULK_DT_WR]);
	usb2_transfer_stop(sc->sc_xfer[RUE_BULK_DT_RD]);
	usb2_transfer_stop(sc->sc_xfer[RUE_BULK_CS_WR]);
	usb2_transfer_stop(sc->sc_xfer[RUE_BULK_CS_RD]);
	usb2_transfer_stop(sc->sc_xfer[RUE_INTR_DT_RD]);
	usb2_transfer_stop(sc->sc_xfer[RUE_INTR_CS_RD]);
}

static void
rue_cfg_stop(struct rue_softc *sc,
    struct usb2_config_td_cc *cc, uint16_t refcount)
{
	rue_cfg_csr_write_1(sc, RUE_CR, 0x00);

	rue_cfg_reset(sc);
}

/*
 * Stop all chip I/O so that the kernel's probe routines don't
 * get confused by errant DMAs when rebooting.
 */
static int
rue_shutdown(device_t dev)
{
	struct rue_softc *sc = device_get_softc(dev);

	mtx_lock(&sc->sc_mtx);

	usb2_config_td_queue_command
	    (&sc->sc_config_td, &rue_cfg_pre_stop,
	    &rue_cfg_stop, 0, 0);

	mtx_unlock(&sc->sc_mtx);

	return (0);
}