/*      $OpenBSD: if_ral.c,v 1.150 2024/05/23 03:21:08 jsg Exp $        */

/*-
 * Copyright (c) 2005, 2006
 *      Damien Bergamini <damien.bergamini@free.fr>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*-
 * Ralink Technology RT2500USB chipset driver
 * http://www.ralinktech.com.tw/
 */

#include "bpfilter.h"

#include <sys/param.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/systm.h>
#include <sys/timeout.h>
#include <sys/device.h>
#include <sys/endian.h>

#include <machine/intr.h>

#if NBPFILTER > 0
#include <net/bpf.h>
#endif
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>

#include <netinet/in.h>
#include <netinet/if_ether.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_amrr.h>
#include <net80211/ieee80211_radiotap.h>

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

#include <dev/usb/if_ralreg.h>
#include <dev/usb/if_ralvar.h>

#ifdef URAL_DEBUG
#define DPRINTF(x)      do { if (ural_debug) printf x; } while (0)
#define DPRINTFN(n, x)  do { if (ural_debug >= (n)) printf x; } while (0)
int ural_debug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

/* various supported device vendors/products */
static const struct usb_devno ural_devs[] = {
        { USB_VENDOR_ASUS,              USB_PRODUCT_ASUS_RT2570 },
        { USB_VENDOR_ASUS,              USB_PRODUCT_ASUS_RT2570_2 },
        { USB_VENDOR_BELKIN,            USB_PRODUCT_BELKIN_F5D7050 },
        { USB_VENDOR_CISCOLINKSYS,      USB_PRODUCT_CISCOLINKSYS_WUSB54G },
        { USB_VENDOR_CISCOLINKSYS,      USB_PRODUCT_CISCOLINKSYS_WUSB54GP },
        { USB_VENDOR_CISCOLINKSYS,      USB_PRODUCT_CISCOLINKSYS_HU200TS },
        { USB_VENDOR_CONCEPTRONIC2,     USB_PRODUCT_CONCEPTRONIC2_C54RU },
        { USB_VENDOR_DLINK,             USB_PRODUCT_DLINK_RT2570 },
        { USB_VENDOR_GIGABYTE,          USB_PRODUCT_GIGABYTE_GNWBKG },
        { USB_VENDOR_GUILLEMOT,         USB_PRODUCT_GUILLEMOT_HWGUSB254 },
        { USB_VENDOR_MELCO,             USB_PRODUCT_MELCO_KG54 },
        { USB_VENDOR_MELCO,             USB_PRODUCT_MELCO_KG54AI },
        { USB_VENDOR_MELCO,             USB_PRODUCT_MELCO_KG54YB },
        { USB_VENDOR_MELCO,             USB_PRODUCT_MELCO_NINWIFI },
        { USB_VENDOR_MSI,               USB_PRODUCT_MSI_RT2570 },
        { USB_VENDOR_MSI,               USB_PRODUCT_MSI_RT2570_2 },
        { USB_VENDOR_MSI,               USB_PRODUCT_MSI_RT2570_3 },
        { USB_VENDOR_NOVATECH,          USB_PRODUCT_NOVATECH_NV902W },
        { USB_VENDOR_RALINK,            USB_PRODUCT_RALINK_RT2570 },
        { USB_VENDOR_RALINK,            USB_PRODUCT_RALINK_RT2570_2 },
        { USB_VENDOR_RALINK,            USB_PRODUCT_RALINK_RT2570_3 },
        { USB_VENDOR_SPHAIRON,          USB_PRODUCT_SPHAIRON_UB801R },
        { USB_VENDOR_SURECOM,           USB_PRODUCT_SURECOM_RT2570 },
        { USB_VENDOR_VTECH,             USB_PRODUCT_VTECH_RT2570 },
        { USB_VENDOR_ZINWELL,           USB_PRODUCT_ZINWELL_RT2570 }
};

int             ural_alloc_tx_list(struct ural_softc *);
void            ural_free_tx_list(struct ural_softc *);
int             ural_alloc_rx_list(struct ural_softc *);
void            ural_free_rx_list(struct ural_softc *);
int             ural_media_change(struct ifnet *);
void            ural_next_scan(void *);
void            ural_task(void *);
int             ural_newstate(struct ieee80211com *, enum ieee80211_state,
                    int);
void            ural_txeof(struct usbd_xfer *, void *, usbd_status);
void            ural_rxeof(struct usbd_xfer *, void *, usbd_status);
#if NBPFILTER > 0
uint8_t         ural_rxrate(const struct ural_rx_desc *);
#endif
int             ural_ack_rate(struct ieee80211com *, int);
uint16_t        ural_txtime(int, int, uint32_t);
uint8_t         ural_plcp_signal(int);
void            ural_setup_tx_desc(struct ural_softc *, struct ural_tx_desc *,
                    uint32_t, int, int);
#ifndef IEEE80211_STA_ONLY
int             ural_tx_bcn(struct ural_softc *, struct mbuf *,
                    struct ieee80211_node *);
#endif
int             ural_tx_data(struct ural_softc *, struct mbuf *,
                    struct ieee80211_node *);
void            ural_start(struct ifnet *);
void            ural_watchdog(struct ifnet *);
int             ural_ioctl(struct ifnet *, u_long, caddr_t);
void            ural_eeprom_read(struct ural_softc *, uint16_t, void *, int);
uint16_t        ural_read(struct ural_softc *, uint16_t);
void            ural_read_multi(struct ural_softc *, uint16_t, void *, int);
void            ural_write(struct ural_softc *, uint16_t, uint16_t);
void            ural_write_multi(struct ural_softc *, uint16_t, void *, int);
void            ural_bbp_write(struct ural_softc *, uint8_t, uint8_t);
uint8_t         ural_bbp_read(struct ural_softc *, uint8_t);
void            ural_rf_write(struct ural_softc *, uint8_t, uint32_t);
void            ural_set_chan(struct ural_softc *, struct ieee80211_channel *);
void            ural_disable_rf_tune(struct ural_softc *);
void            ural_enable_tsf_sync(struct ural_softc *);
void            ural_update_slot(struct ural_softc *);
void            ural_set_txpreamble(struct ural_softc *);
void            ural_set_basicrates(struct ural_softc *);
void            ural_set_bssid(struct ural_softc *, const uint8_t *);
void            ural_set_macaddr(struct ural_softc *, const uint8_t *);
void            ural_update_promisc(struct ural_softc *);
const char      *ural_get_rf(int);
void            ural_read_eeprom(struct ural_softc *);
int             ural_bbp_init(struct ural_softc *);
void            ural_set_txantenna(struct ural_softc *, int);
void            ural_set_rxantenna(struct ural_softc *, int);
int             ural_init(struct ifnet *);
void            ural_stop(struct ifnet *, int);
void            ural_newassoc(struct ieee80211com *, struct ieee80211_node *,
                    int);
void            ural_amrr_start(struct ural_softc *, struct ieee80211_node *);
void            ural_amrr_timeout(void *);
void            ural_amrr_update(struct usbd_xfer *, void *,
                    usbd_status status);

static const struct {
        uint16_t        reg;
        uint16_t        val;
} ural_def_mac[] = {
        RAL_DEF_MAC
};

static const struct {
        uint8_t reg;
        uint8_t val;
} ural_def_bbp[] = {
        RAL_DEF_BBP
};

static const uint32_t ural_rf2522_r2[] =    RAL_RF2522_R2;
static const uint32_t ural_rf2523_r2[] =    RAL_RF2523_R2;
static const uint32_t ural_rf2524_r2[] =    RAL_RF2524_R2;
static const uint32_t ural_rf2525_r2[] =    RAL_RF2525_R2;
static const uint32_t ural_rf2525_hi_r2[] = RAL_RF2525_HI_R2;
static const uint32_t ural_rf2525e_r2[] =   RAL_RF2525E_R2;
static const uint32_t ural_rf2526_hi_r2[] = RAL_RF2526_HI_R2;
static const uint32_t ural_rf2526_r2[] =    RAL_RF2526_R2;

int ural_match(struct device *, void *, void *);
void ural_attach(struct device *, struct device *, void *);
int ural_detach(struct device *, int);

struct cfdriver ural_cd = {
        NULL, "ural", DV_IFNET
};

const struct cfattach ural_ca = {
        sizeof(struct ural_softc), ural_match, ural_attach, ural_detach
};

int
ural_match(struct device *parent, void *match, void *aux)
{
        struct usb_attach_arg *uaa = aux;

        if (uaa->configno != RAL_CONFIG_NO || uaa->ifaceno != RAL_IFACE_NO)
                return UMATCH_NONE;

        return (usb_lookup(ural_devs, uaa->vendor, uaa->product) != NULL) ?
            UMATCH_VENDOR_PRODUCT : UMATCH_NONE;
}

void
ural_attach(struct device *parent, struct device *self, void *aux)
{
        struct ural_softc *sc = (struct ural_softc *)self;
        struct usb_attach_arg *uaa = aux;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &ic->ic_if;
        usb_interface_descriptor_t *id;
        usb_endpoint_descriptor_t *ed;
        int i;

        sc->sc_udev = uaa->device;
        sc->sc_iface = uaa->iface;

        /*
         * Find endpoints.
         */
        id = usbd_get_interface_descriptor(sc->sc_iface);

        sc->sc_rx_no = sc->sc_tx_no = -1;
        for (i = 0; i < id->bNumEndpoints; i++) {
                ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
                if (ed == NULL) {
                        printf("%s: no endpoint descriptor for iface %d\n",
                            sc->sc_dev.dv_xname, i);
                        return;
                }

                if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK)
                        sc->sc_rx_no = ed->bEndpointAddress;
                else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK)
                        sc->sc_tx_no = ed->bEndpointAddress;
        }
        if (sc->sc_rx_no == -1 || sc->sc_tx_no == -1) {
                printf("%s: missing endpoint\n", sc->sc_dev.dv_xname);
                return;
        }

        usb_init_task(&sc->sc_task, ural_task, sc, USB_TASK_TYPE_GENERIC);
        timeout_set(&sc->scan_to, ural_next_scan, sc);

        sc->amrr.amrr_min_success_threshold =  1;
        sc->amrr.amrr_max_success_threshold = 10;
        timeout_set(&sc->amrr_to, ural_amrr_timeout, sc);

        /* retrieve RT2570 rev. no */
        sc->asic_rev = ural_read(sc, RAL_MAC_CSR0);

        /* retrieve MAC address and various other things from EEPROM */
        ural_read_eeprom(sc);

        printf("%s: MAC/BBP RT%04x (rev 0x%02x), RF %s, address %s\n",
            sc->sc_dev.dv_xname, sc->macbbp_rev, sc->asic_rev,
            ural_get_rf(sc->rf_rev), ether_sprintf(ic->ic_myaddr));

        ic->ic_phytype = IEEE80211_T_OFDM;      /* not only, but not used */
        ic->ic_opmode = IEEE80211_M_STA;        /* default to BSS mode */
        ic->ic_state = IEEE80211_S_INIT;

        /* set device capabilities */
        ic->ic_caps =
            IEEE80211_C_MONITOR |       /* monitor mode supported */
#ifndef IEEE80211_STA_ONLY
            IEEE80211_C_IBSS |          /* IBSS mode supported */
            IEEE80211_C_HOSTAP |        /* HostAp mode supported */
#endif
            IEEE80211_C_TXPMGT |        /* tx power management */
            IEEE80211_C_SHPREAMBLE |    /* short preamble supported */
            IEEE80211_C_SHSLOT |        /* short slot time supported */
            IEEE80211_C_WEP |           /* s/w WEP */
            IEEE80211_C_RSN;            /* WPA/RSN */

        /* set supported .11b and .11g rates */
        ic->ic_sup_rates[IEEE80211_MODE_11B] = ieee80211_std_rateset_11b;
        ic->ic_sup_rates[IEEE80211_MODE_11G] = ieee80211_std_rateset_11g;

        /* set supported .11b and .11g channels (1 through 14) */
        for (i = 1; i <= 14; i++) {
                ic->ic_channels[i].ic_freq =
                    ieee80211_ieee2mhz(i, IEEE80211_CHAN_2GHZ);
                ic->ic_channels[i].ic_flags =
                    IEEE80211_CHAN_CCK | IEEE80211_CHAN_OFDM |
                    IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
        }

        ifp->if_softc = sc;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_ioctl = ural_ioctl;
        ifp->if_start = ural_start;
        ifp->if_watchdog = ural_watchdog;
        memcpy(ifp->if_xname, sc->sc_dev.dv_xname, IFNAMSIZ);

        if_attach(ifp);
        ieee80211_ifattach(ifp);
        ic->ic_newassoc = ural_newassoc;

        /* override state transition machine */
        sc->sc_newstate = ic->ic_newstate;
        ic->ic_newstate = ural_newstate;
        ieee80211_media_init(ifp, ural_media_change, ieee80211_media_status);

#if NBPFILTER > 0
        bpfattach(&sc->sc_drvbpf, ifp, DLT_IEEE802_11_RADIO,
            sizeof (struct ieee80211_frame) + 64);

        sc->sc_rxtap_len = sizeof sc->sc_rxtapu;
        sc->sc_rxtap.wr_ihdr.it_len = htole16(sc->sc_rxtap_len);
        sc->sc_rxtap.wr_ihdr.it_present = htole32(RAL_RX_RADIOTAP_PRESENT);

        sc->sc_txtap_len = sizeof sc->sc_txtapu;
        sc->sc_txtap.wt_ihdr.it_len = htole16(sc->sc_txtap_len);
        sc->sc_txtap.wt_ihdr.it_present = htole32(RAL_TX_RADIOTAP_PRESENT);
#endif
}

int
ural_detach(struct device *self, int flags)
{
        struct ural_softc *sc = (struct ural_softc *)self;
        struct ifnet *ifp = &sc->sc_ic.ic_if;
        int s;

        s = splusb();

        if (timeout_initialized(&sc->scan_to))
                timeout_del(&sc->scan_to);
        if (timeout_initialized(&sc->amrr_to))
                timeout_del(&sc->amrr_to);

        usb_rem_wait_task(sc->sc_udev, &sc->sc_task);

        usbd_ref_wait(sc->sc_udev);

        if (ifp->if_softc != NULL) {
                ieee80211_ifdetach(ifp);        /* free all nodes */
                if_detach(ifp);
        }

        if (sc->amrr_xfer != NULL) {
                usbd_free_xfer(sc->amrr_xfer);
                sc->amrr_xfer = NULL;
        }

        if (sc->sc_rx_pipeh != NULL)
                usbd_close_pipe(sc->sc_rx_pipeh);

        if (sc->sc_tx_pipeh != NULL)
                usbd_close_pipe(sc->sc_tx_pipeh);

        ural_free_rx_list(sc);
        ural_free_tx_list(sc);

        splx(s);

        return 0;
}

int
ural_alloc_tx_list(struct ural_softc *sc)
{
        int i, error;

        sc->tx_cur = sc->tx_queued = 0;

        for (i = 0; i < RAL_TX_LIST_COUNT; i++) {
                struct ural_tx_data *data = &sc->tx_data[i];

                data->sc = sc;

                data->xfer = usbd_alloc_xfer(sc->sc_udev);
                if (data->xfer == NULL) {
                        printf("%s: could not allocate tx xfer\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }
                data->buf = usbd_alloc_buffer(data->xfer,
                    RAL_TX_DESC_SIZE + IEEE80211_MAX_LEN);
                if (data->buf == NULL) {
                        printf("%s: could not allocate tx buffer\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }
        }

        return 0;

fail:   ural_free_tx_list(sc);
        return error;
}

void
ural_free_tx_list(struct ural_softc *sc)
{
        int i;

        for (i = 0; i < RAL_TX_LIST_COUNT; i++) {
                struct ural_tx_data *data = &sc->tx_data[i];

                if (data->xfer != NULL) {
                        usbd_free_xfer(data->xfer);
                        data->xfer = NULL;
                }
                /*
                 * The node has already been freed at that point so don't call
                 * ieee80211_release_node() here.
                 */
                data->ni = NULL;
        }
}

int
ural_alloc_rx_list(struct ural_softc *sc)
{
        int i, error;

        for (i = 0; i < RAL_RX_LIST_COUNT; i++) {
                struct ural_rx_data *data = &sc->rx_data[i];

                data->sc = sc;

                data->xfer = usbd_alloc_xfer(sc->sc_udev);
                if (data->xfer == NULL) {
                        printf("%s: could not allocate rx xfer\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }
                if (usbd_alloc_buffer(data->xfer, MCLBYTES) == NULL) {
                        printf("%s: could not allocate rx buffer\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }

                MGETHDR(data->m, M_DONTWAIT, MT_DATA);
                if (data->m == NULL) {
                        printf("%s: could not allocate rx mbuf\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }
                MCLGET(data->m, M_DONTWAIT);
                if (!(data->m->m_flags & M_EXT)) {
                        printf("%s: could not allocate rx mbuf cluster\n",
                            sc->sc_dev.dv_xname);
                        error = ENOMEM;
                        goto fail;
                }
                data->buf = mtod(data->m, uint8_t *);
        }

        return 0;

fail:   ural_free_rx_list(sc);
        return error;
}

void
ural_free_rx_list(struct ural_softc *sc)
{
        int i;

        for (i = 0; i < RAL_RX_LIST_COUNT; i++) {
                struct ural_rx_data *data = &sc->rx_data[i];

                if (data->xfer != NULL) {
                        usbd_free_xfer(data->xfer);
                        data->xfer = NULL;
                }
                if (data->m != NULL) {
                        m_freem(data->m);
                        data->m = NULL;
                }
        }
}

int
ural_media_change(struct ifnet *ifp)
{
        int error;

        error = ieee80211_media_change(ifp);
        if (error != ENETRESET)
                return error;

        if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
                error = ural_init(ifp);

        return error;
}

/*
 * This function is called periodically (every 200ms) during scanning to
 * switch from one channel to another.
 */
void
ural_next_scan(void *arg)
{
        struct ural_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &ic->ic_if;

        if (usbd_is_dying(sc->sc_udev))
                return;

        usbd_ref_incr(sc->sc_udev);

        if (ic->ic_state == IEEE80211_S_SCAN)
                ieee80211_next_scan(ifp);

        usbd_ref_decr(sc->sc_udev);
}

void
ural_task(void *arg)
{
        struct ural_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;
        enum ieee80211_state ostate;
        struct ieee80211_node *ni;

        if (usbd_is_dying(sc->sc_udev))
                return;

        ostate = ic->ic_state;

        switch (sc->sc_state) {
        case IEEE80211_S_INIT:
                if (ostate == IEEE80211_S_RUN) {
                        /* abort TSF synchronization */
                        ural_write(sc, RAL_TXRX_CSR19, 0);

                        /* force tx led to stop blinking */
                        ural_write(sc, RAL_MAC_CSR20, 0);
                }
                break;

        case IEEE80211_S_SCAN:
                ural_set_chan(sc, ic->ic_bss->ni_chan);
                if (!usbd_is_dying(sc->sc_udev))
                        timeout_add_msec(&sc->scan_to, 200);
                break;

        case IEEE80211_S_AUTH:
                ural_set_chan(sc, ic->ic_bss->ni_chan);
                break;

        case IEEE80211_S_ASSOC:
                ural_set_chan(sc, ic->ic_bss->ni_chan);
                break;

        case IEEE80211_S_RUN:
                ural_set_chan(sc, ic->ic_bss->ni_chan);

                ni = ic->ic_bss;

                if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                        ural_update_slot(sc);
                        ural_set_txpreamble(sc);
                        ural_set_basicrates(sc);
                        ural_set_bssid(sc, ni->ni_bssid);
                }

#ifndef IEEE80211_STA_ONLY
                if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
                    ic->ic_opmode == IEEE80211_M_IBSS) {
                        struct mbuf *m = ieee80211_beacon_alloc(ic, ni);
                        if (m == NULL) {
                                printf("%s: could not allocate beacon\n",
                                    sc->sc_dev.dv_xname);
                                return;
                        }

                        if (ural_tx_bcn(sc, m, ni) != 0) {
                                m_freem(m);
                                printf("%s: could not transmit beacon\n",
                                    sc->sc_dev.dv_xname);
                                return;
                        }

                        /* beacon is no longer needed */
                        m_freem(m);
                }
#endif

                /* make tx led blink on tx (controlled by ASIC) */
                ural_write(sc, RAL_MAC_CSR20, 1);

                if (ic->ic_opmode != IEEE80211_M_MONITOR)
                        ural_enable_tsf_sync(sc);

                if (ic->ic_opmode == IEEE80211_M_STA) {
                        /* fake a join to init the tx rate */
                        ural_newassoc(ic, ic->ic_bss, 1);

                        /* enable automatic rate control in STA mode */
                        if (ic->ic_fixed_rate == -1)
                                ural_amrr_start(sc, ic->ic_bss);
                }

                break;
        }

        sc->sc_newstate(ic, sc->sc_state, sc->sc_arg);
}

int
ural_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
        struct ural_softc *sc = ic->ic_if.if_softc;

        usb_rem_task(sc->sc_udev, &sc->sc_task);
        timeout_del(&sc->scan_to);
        timeout_del(&sc->amrr_to);

        /* do it in a process context */
        sc->sc_state = nstate;
        sc->sc_arg = arg;
        usb_add_task(sc->sc_udev, &sc->sc_task);
        return 0;
}

/* quickly determine if a given rate is CCK or OFDM */
#define RAL_RATE_IS_OFDM(rate) ((rate) >= 12 && (rate) != 22)

#define RAL_ACK_SIZE    14      /* 10 + 4(FCS) */
#define RAL_CTS_SIZE    14      /* 10 + 4(FCS) */

#define RAL_SIFS                10      /* us */

#define RAL_RXTX_TURNAROUND     5       /* us */

void
ural_txeof(struct usbd_xfer *xfer, void *priv, usbd_status status)
{
        struct ural_tx_data *data = priv;
        struct ural_softc *sc = data->sc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &ic->ic_if;
        int s;

        if (status != USBD_NORMAL_COMPLETION) {
                if (status == USBD_NOT_STARTED || status == USBD_CANCELLED)
                        return;

                printf("%s: could not transmit buffer: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(status));

                if (status == USBD_STALLED)
                        usbd_clear_endpoint_stall_async(sc->sc_tx_pipeh);

                ifp->if_oerrors++;
                return;
        }

        s = splnet();

        ieee80211_release_node(ic, data->ni);
        data->ni = NULL;

        sc->tx_queued--;

        DPRINTFN(10, ("tx done\n"));

        sc->sc_tx_timer = 0;
        ifq_clr_oactive(&ifp->if_snd);
        ural_start(ifp);

        splx(s);
}

void
ural_rxeof(struct usbd_xfer *xfer, void *priv, usbd_status status)
{
        struct ural_rx_data *data = priv;
        struct ural_softc *sc = data->sc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &ic->ic_if;
        const struct ural_rx_desc *desc;
        struct ieee80211_frame *wh;
        struct ieee80211_rxinfo rxi;
        struct ieee80211_node *ni;
        struct mbuf *mnew, *m;
        int s, len;

        if (status != USBD_NORMAL_COMPLETION) {
                if (status == USBD_NOT_STARTED || status == USBD_CANCELLED)
                        return;

                if (status == USBD_STALLED)
                        usbd_clear_endpoint_stall_async(sc->sc_rx_pipeh);
                goto skip;
        }

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

        if (len < RAL_RX_DESC_SIZE + IEEE80211_MIN_LEN) {
                DPRINTF(("%s: xfer too short %d\n", sc->sc_dev.dv_xname,
                    len));
                ifp->if_ierrors++;
                goto skip;
        }

        /* rx descriptor is located at the end */
        desc = (struct ural_rx_desc *)(data->buf + len - RAL_RX_DESC_SIZE);

        if (letoh32(desc->flags) & (RAL_RX_PHY_ERROR | RAL_RX_CRC_ERROR)) {
                /*
                 * This should not happen since we did not request to receive
                 * those frames when we filled RAL_TXRX_CSR2.
                 */
                DPRINTFN(5, ("PHY or CRC error\n"));
                ifp->if_ierrors++;
                goto skip;
        }

        MGETHDR(mnew, M_DONTWAIT, MT_DATA);
        if (mnew == NULL) {
                printf("%s: could not allocate rx mbuf\n",
                    sc->sc_dev.dv_xname);
                ifp->if_ierrors++;
                goto skip;
        }
        MCLGET(mnew, M_DONTWAIT);
        if (!(mnew->m_flags & M_EXT)) {
                printf("%s: could not allocate rx mbuf cluster\n",
                    sc->sc_dev.dv_xname);
                m_freem(mnew);
                ifp->if_ierrors++;
                goto skip;
        }
        m = data->m;
        data->m = mnew;
        data->buf = mtod(data->m, uint8_t *);

        /* finalize mbuf */
        m->m_pkthdr.len = m->m_len = (letoh32(desc->flags) >> 16) & 0xfff;

        s = splnet();

#if NBPFILTER > 0
        if (sc->sc_drvbpf != NULL) {
                struct mbuf mb;
                struct ural_rx_radiotap_header *tap = &sc->sc_rxtap;

                tap->wr_flags = IEEE80211_RADIOTAP_F_FCS;
                tap->wr_rate = ural_rxrate(desc);
                tap->wr_chan_freq = htole16(ic->ic_bss->ni_chan->ic_freq);
                tap->wr_chan_flags = htole16(ic->ic_bss->ni_chan->ic_flags);
                tap->wr_antenna = sc->rx_ant;
                tap->wr_antsignal = desc->rssi;

                mb.m_data = (caddr_t)tap;
                mb.m_len = sc->sc_rxtap_len;
                mb.m_next = m;
                mb.m_nextpkt = NULL;
                mb.m_type = 0;
                mb.m_flags = 0;
                bpf_mtap(sc->sc_drvbpf, &mb, BPF_DIRECTION_IN);
        }
#endif
        m_adj(m, -IEEE80211_CRC_LEN);   /* trim FCS */

        wh = mtod(m, struct ieee80211_frame *);
        ni = ieee80211_find_rxnode(ic, wh);

        /* send the frame to the 802.11 layer */
        memset(&rxi, 0, sizeof(rxi));
        rxi.rxi_rssi = desc->rssi;
        ieee80211_input(ifp, m, ni, &rxi);

        /* node is no longer needed */
        ieee80211_release_node(ic, ni);

        splx(s);

        DPRINTFN(15, ("rx done\n"));

skip:   /* setup a new transfer */
        usbd_setup_xfer(xfer, sc->sc_rx_pipeh, data, data->buf, MCLBYTES,
            USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, ural_rxeof);
        (void)usbd_transfer(xfer);
}

/*
 * This function is only used by the Rx radiotap code. It returns the rate at
 * which a given frame was received.
 */
#if NBPFILTER > 0
uint8_t
ural_rxrate(const struct ural_rx_desc *desc)
{
        if (letoh32(desc->flags) & RAL_RX_OFDM) {
                /* reverse function of ural_plcp_signal */
                switch (desc->rate) {
                case 0xb:       return 12;
                case 0xf:       return 18;
                case 0xa:       return 24;
                case 0xe:       return 36;
                case 0x9:       return 48;
                case 0xd:       return 72;
                case 0x8:       return 96;
                case 0xc:       return 108;
                }
        } else {
                if (desc->rate == 10)
                        return 2;
                if (desc->rate == 20)
                        return 4;
                if (desc->rate == 55)
                        return 11;
                if (desc->rate == 110)
                        return 22;
        }
        return 2;       /* should not get there */
}
#endif

/*
 * Return the expected ack rate for a frame transmitted at rate `rate'.
 */
int
ural_ack_rate(struct ieee80211com *ic, int rate)
{
        switch (rate) {
        /* CCK rates */
        case 2:
                return 2;
        case 4:
        case 11:
        case 22:
                return (ic->ic_curmode == IEEE80211_MODE_11B) ? 4 : rate;

        /* OFDM rates */
        case 12:
        case 18:
                return 12;
        case 24:
        case 36:
                return 24;
        case 48:
        case 72:
        case 96:
        case 108:
                return 48;
        }

        /* default to 1Mbps */
        return 2;
}

/*
 * Compute the duration (in us) needed to transmit `len' bytes at rate `rate'.
 * The function automatically determines the operating mode depending on the
 * given rate. `flags' indicates whether short preamble is in use or not.
 */
uint16_t
ural_txtime(int len, int rate, uint32_t flags)
{
        uint16_t txtime;

        if (RAL_RATE_IS_OFDM(rate)) {
                /* IEEE Std 802.11g-2003, pp. 44 */
                txtime = (8 + 4 * len + 3 + rate - 1) / rate;
                txtime = 16 + 4 + 4 * txtime + 6;
        } else {
                /* IEEE Std 802.11b-1999, pp. 28 */
                txtime = (16 * len + rate - 1) / rate;
                if (rate != 2 && (flags & IEEE80211_F_SHPREAMBLE))
                        txtime +=  72 + 24;
                else
                        txtime += 144 + 48;
        }
        return txtime;
}

uint8_t
ural_plcp_signal(int rate)
{
        switch (rate) {
        /* CCK rates (returned values are device-dependent) */
        case 2:         return 0x0;
        case 4:         return 0x1;
        case 11:        return 0x2;
        case 22:        return 0x3;

        /* OFDM rates (cf IEEE Std 802.11a-1999, pp. 14 Table 80) */
        case 12:        return 0xb;
        case 18:        return 0xf;
        case 24:        return 0xa;
        case 36:        return 0xe;
        case 48:        return 0x9;
        case 72:        return 0xd;
        case 96:        return 0x8;
        case 108:       return 0xc;

        /* unsupported rates (should not get there) */
        default:        return 0xff;
        }
}

void
ural_setup_tx_desc(struct ural_softc *sc, struct ural_tx_desc *desc,
    uint32_t flags, int len, int rate)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t plcp_length;
        int remainder;

        desc->flags = htole32(flags);
        desc->flags |= htole32(len << 16);

        desc->wme = htole16(
            RAL_AIFSN(2) |
            RAL_LOGCWMIN(3) |
            RAL_LOGCWMAX(5));

        /* setup PLCP fields */
        desc->plcp_signal  = ural_plcp_signal(rate);
        desc->plcp_service = 4;

        len += IEEE80211_CRC_LEN;
        if (RAL_RATE_IS_OFDM(rate)) {
                desc->flags |= htole32(RAL_TX_OFDM);

                plcp_length = len & 0xfff;
                desc->plcp_length_hi = plcp_length >> 6;
                desc->plcp_length_lo = plcp_length & 0x3f;
        } else {
                plcp_length = (16 * len + rate - 1) / rate;
                if (rate == 22) {
                        remainder = (16 * len) % 22;
                        if (remainder != 0 && remainder < 7)
                                desc->plcp_service |= RAL_PLCP_LENGEXT;
                }
                desc->plcp_length_hi = plcp_length >> 8;
                desc->plcp_length_lo = plcp_length & 0xff;

                if (rate != 2 && (ic->ic_flags & IEEE80211_F_SHPREAMBLE))
                        desc->plcp_signal |= 0x08;
        }

        desc->iv = 0;
        desc->eiv = 0;
}

#define RAL_TX_TIMEOUT  5000

#ifndef IEEE80211_STA_ONLY
int
ural_tx_bcn(struct ural_softc *sc, struct mbuf *m0, struct ieee80211_node *ni)
{
        struct ural_tx_desc *desc;
        struct usbd_xfer *xfer;
        usbd_status error;
        uint8_t cmd = 0;
        uint8_t *buf;
        int xferlen, rate = 2;

        xfer = usbd_alloc_xfer(sc->sc_udev);
        if (xfer == NULL)
                return ENOMEM;

        /* xfer length needs to be a multiple of two! */
        xferlen = (RAL_TX_DESC_SIZE + m0->m_pkthdr.len + 1) & ~1;

        buf = usbd_alloc_buffer(xfer, xferlen);
        if (buf == NULL) {
                usbd_free_xfer(xfer);
                return ENOMEM;
        }

        usbd_setup_xfer(xfer, sc->sc_tx_pipeh, NULL, &cmd, sizeof cmd,
            USBD_FORCE_SHORT_XFER | USBD_SYNCHRONOUS, RAL_TX_TIMEOUT, NULL);

        error = usbd_transfer(xfer);
        if (error != 0) {
                usbd_free_xfer(xfer);
                return error;
        }

        desc = (struct ural_tx_desc *)buf;

        m_copydata(m0, 0, m0->m_pkthdr.len, buf + RAL_TX_DESC_SIZE);
        ural_setup_tx_desc(sc, desc, RAL_TX_IFS_NEWBACKOFF | RAL_TX_TIMESTAMP,
            m0->m_pkthdr.len, rate);

        DPRINTFN(10, ("sending beacon frame len=%u rate=%u xfer len=%u\n",
            m0->m_pkthdr.len, rate, xferlen));

        usbd_setup_xfer(xfer, sc->sc_tx_pipeh, NULL, buf, xferlen,
            USBD_FORCE_SHORT_XFER | USBD_NO_COPY | USBD_SYNCHRONOUS,
            RAL_TX_TIMEOUT, NULL);

        error = usbd_transfer(xfer);
        usbd_free_xfer(xfer);

        return error;
}
#endif

int
ural_tx_data(struct ural_softc *sc, struct mbuf *m0, struct ieee80211_node *ni)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ural_tx_desc *desc;
        struct ural_tx_data *data;
        struct ieee80211_frame *wh;
        struct ieee80211_key *k;
        uint32_t flags = RAL_TX_NEWSEQ;
        uint16_t dur;
        usbd_status error;
        int rate, xferlen, pktlen, needrts = 0, needcts = 0;

        wh = mtod(m0, struct ieee80211_frame *);

        if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
                k = ieee80211_get_txkey(ic, wh, ni);

                if ((m0 = ieee80211_encrypt(ic, m0, k)) == NULL)
                        return ENOBUFS;

                /* packet header may have moved, reset our local pointer */
                wh = mtod(m0, struct ieee80211_frame *);
        }

        /* compute actual packet length (including CRC and crypto overhead) */
        pktlen = m0->m_pkthdr.len + IEEE80211_CRC_LEN;

        /* pickup a rate */
        if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
            ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) ==
             IEEE80211_FC0_TYPE_MGT)) {
                /* mgmt/multicast frames are sent at the lowest avail. rate */
                rate = ni->ni_rates.rs_rates[0];
        } else if (ic->ic_fixed_rate != -1) {
                rate = ic->ic_sup_rates[ic->ic_curmode].
                    rs_rates[ic->ic_fixed_rate];
        } else
                        rate = ni->ni_rates.rs_rates[ni->ni_txrate];
        if (rate == 0)
                rate = 2;       /* XXX should not happen */
        rate &= IEEE80211_RATE_VAL;

        /* check if RTS/CTS or CTS-to-self protection must be used */
        if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
                /* multicast frames are not sent at OFDM rates in 802.11b/g */
                if (pktlen > ic->ic_rtsthreshold) {
                        needrts = 1;    /* RTS/CTS based on frame length */
                } else if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
                    RAL_RATE_IS_OFDM(rate)) {
                        if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
                                needcts = 1;    /* CTS-to-self */
                        else if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
                                needrts = 1;    /* RTS/CTS */
                }
        }
        if (needrts || needcts) {
                struct mbuf *mprot;
                int protrate, ackrate;
                uint16_t dur;

                protrate = 2;
                ackrate  = ural_ack_rate(ic, rate);

                dur = ural_txtime(pktlen, rate, ic->ic_flags) +
                      ural_txtime(RAL_ACK_SIZE, ackrate, ic->ic_flags) +
                      2 * RAL_SIFS;
                if (needrts) {
                        dur += ural_txtime(RAL_CTS_SIZE, ural_ack_rate(ic,
                            protrate), ic->ic_flags) + RAL_SIFS;
                        mprot = ieee80211_get_rts(ic, wh, dur);
                } else {
                        mprot = ieee80211_get_cts_to_self(ic, dur);
                }
                if (mprot == NULL) {
                        printf("%s: could not allocate protection frame\n",
                            sc->sc_dev.dv_xname);
                        m_freem(m0);
                        return ENOBUFS;
                }

                data = &sc->tx_data[sc->tx_cur];
                desc = (struct ural_tx_desc *)data->buf;

                /* avoid multiple free() of the same node for each fragment */
                data->ni = ieee80211_ref_node(ni);

                m_copydata(mprot, 0, mprot->m_pkthdr.len,
                    data->buf + RAL_TX_DESC_SIZE);
                ural_setup_tx_desc(sc, desc,
                    (needrts ? RAL_TX_NEED_ACK : 0) | RAL_TX_RETRY(7),
                    mprot->m_pkthdr.len, protrate);

                /* no roundup necessary here */
                xferlen = RAL_TX_DESC_SIZE + mprot->m_pkthdr.len;

                /* XXX may want to pass the protection frame to BPF */

                /* mbuf is no longer needed */
                m_freem(mprot);

                usbd_setup_xfer(data->xfer, sc->sc_tx_pipeh, data, data->buf,
                    xferlen, USBD_FORCE_SHORT_XFER | USBD_NO_COPY,
                    RAL_TX_TIMEOUT, ural_txeof);
                error = usbd_transfer(data->xfer);
                if (error != 0 && error != USBD_IN_PROGRESS) {
                        m_freem(m0);
                        return error;
                }

                sc->tx_queued++;
                sc->tx_cur = (sc->tx_cur + 1) % RAL_TX_LIST_COUNT;

                flags |= RAL_TX_IFS_SIFS;
        }

        data = &sc->tx_data[sc->tx_cur];
        desc = (struct ural_tx_desc *)data->buf;

        data->ni = ni;

        if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
                flags |= RAL_TX_NEED_ACK;
                flags |= RAL_TX_RETRY(7);

                dur = ural_txtime(RAL_ACK_SIZE, ural_ack_rate(ic, rate),
                    ic->ic_flags) + RAL_SIFS;
                *(uint16_t *)wh->i_dur = htole16(dur);

#ifndef IEEE80211_STA_ONLY
                /* tell hardware to set timestamp in probe responses */
                if ((wh->i_fc[0] &
                    (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_MASK)) ==
                    (IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP))
                        flags |= RAL_TX_TIMESTAMP;
#endif
        }

#if NBPFILTER > 0
        if (sc->sc_drvbpf != NULL) {
                struct mbuf mb;
                struct ural_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_rate = rate;
                tap->wt_chan_freq = htole16(ic->ic_bss->ni_chan->ic_freq);
                tap->wt_chan_flags = htole16(ic->ic_bss->ni_chan->ic_flags);
                tap->wt_antenna = sc->tx_ant;

                mb.m_data = (caddr_t)tap;
                mb.m_len = sc->sc_txtap_len;
                mb.m_next = m0;
                mb.m_nextpkt = NULL;
                mb.m_type = 0;
                mb.m_flags = 0;
                bpf_mtap(sc->sc_drvbpf, &mb, BPF_DIRECTION_OUT);
        }
#endif

        m_copydata(m0, 0, m0->m_pkthdr.len, data->buf + RAL_TX_DESC_SIZE);
        ural_setup_tx_desc(sc, desc, flags, m0->m_pkthdr.len, rate);

        /* align end on a 2-bytes boundary */
        xferlen = (RAL_TX_DESC_SIZE + m0->m_pkthdr.len + 1) & ~1;

        /*
         * No space left in the last URB to store the extra 2 bytes, force
         * sending of another URB.
         */
        if ((xferlen % 64) == 0)
                xferlen += 2;

        DPRINTFN(10, ("sending frame len=%u rate=%u xfer len=%u\n",
            m0->m_pkthdr.len, rate, xferlen));

        /* mbuf is no longer needed */
        m_freem(m0);

        usbd_setup_xfer(data->xfer, sc->sc_tx_pipeh, data, data->buf, xferlen,
            USBD_FORCE_SHORT_XFER | USBD_NO_COPY, RAL_TX_TIMEOUT, ural_txeof);
        error = usbd_transfer(data->xfer);
        if (error != 0 && error != USBD_IN_PROGRESS)
                return error;

        sc->tx_queued++;
        sc->tx_cur = (sc->tx_cur + 1) % RAL_TX_LIST_COUNT;

        return 0;
}

void
ural_start(struct ifnet *ifp)
{
        struct ural_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211_node *ni;
        struct mbuf *m0;

        /*
         * net80211 may still try to send management frames even if the
         * IFF_RUNNING flag is not set...
         */
        if (!(ifp->if_flags & IFF_RUNNING) || ifq_is_oactive(&ifp->if_snd))
                return;

        for (;;) {
                if (sc->tx_queued >= RAL_TX_LIST_COUNT - 1) {
                        ifq_set_oactive(&ifp->if_snd);
                        break;
                }

                m0 = mq_dequeue(&ic->ic_mgtq);
                if (m0 != NULL) {
                        ni = m0->m_pkthdr.ph_cookie;
#if NBPFILTER > 0
                        if (ic->ic_rawbpf != NULL)
                                bpf_mtap(ic->ic_rawbpf, m0, BPF_DIRECTION_OUT);
#endif
                        if (ural_tx_data(sc, m0, ni) != 0)
                                break;

                } else {
                        if (ic->ic_state != IEEE80211_S_RUN)
                                break;

                        m0 = ifq_dequeue(&ifp->if_snd);
                        if (m0 == NULL)
                                break;
#if NBPFILTER > 0
                        if (ifp->if_bpf != NULL)
                                bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
#endif
                        m0 = ieee80211_encap(ifp, m0, &ni);
                        if (m0 == NULL)
                                continue;
#if NBPFILTER > 0
                        if (ic->ic_rawbpf != NULL)
                                bpf_mtap(ic->ic_rawbpf, m0, BPF_DIRECTION_OUT);
#endif
                        if (ural_tx_data(sc, m0, ni) != 0) {
                                if (ni != NULL)
                                        ieee80211_release_node(ic, ni);
                                ifp->if_oerrors++;
                                break;
                        }
                }

                sc->sc_tx_timer = 5;
                ifp->if_timer = 1;
        }
}

void
ural_watchdog(struct ifnet *ifp)
{
        struct ural_softc *sc = ifp->if_softc;

        ifp->if_timer = 0;

        if (sc->sc_tx_timer > 0) {
                if (--sc->sc_tx_timer == 0) {
                        printf("%s: device timeout\n", sc->sc_dev.dv_xname);
                        /*ural_init(ifp); XXX needs a process context! */
                        ifp->if_oerrors++;
                        return;
                }
                ifp->if_timer = 1;
        }

        ieee80211_watchdog(ifp);
}

int
ural_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
        struct ural_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        int s, error = 0;

        if (usbd_is_dying(sc->sc_udev))
                return ENXIO;

        usbd_ref_incr(sc->sc_udev);

        s = splnet();

        switch (cmd) {
        case SIOCSIFADDR:
                ifp->if_flags |= IFF_UP;
                /* FALLTHROUGH */
        case SIOCSIFFLAGS:
                if (ifp->if_flags & IFF_UP) {
                        if (ifp->if_flags & IFF_RUNNING)
                                ural_update_promisc(sc);
                        else
                                ural_init(ifp);
                } else {
                        if (ifp->if_flags & IFF_RUNNING)
                                ural_stop(ifp, 1);
                }
                break;

        case SIOCS80211CHANNEL:
                /*
                 * This allows for fast channel switching in monitor mode
                 * (used by kismet). In IBSS mode, we must explicitly reset
                 * the interface to generate a new beacon frame.
                 */
                error = ieee80211_ioctl(ifp, cmd, data);
                if (error == ENETRESET &&
                    ic->ic_opmode == IEEE80211_M_MONITOR) {
                        if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
                            (IFF_UP | IFF_RUNNING))
                                ural_set_chan(sc, ic->ic_ibss_chan);
                        error = 0;
                }
                break;

        default:
                error = ieee80211_ioctl(ifp, cmd, data);
        }

        if (error == ENETRESET) {
                if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
                    (IFF_UP | IFF_RUNNING))
                        ural_init(ifp);
                error = 0;
        }

        splx(s);

        usbd_ref_decr(sc->sc_udev);

        return error;
}

void
ural_eeprom_read(struct ural_softc *sc, uint16_t addr, void *buf, int len)
{
        usb_device_request_t req;
        usbd_status error;

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

        error = usbd_do_request(sc->sc_udev, &req, buf);
        if (error != 0) {
                printf("%s: could not read EEPROM: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
        }
}

uint16_t
ural_read(struct ural_softc *sc, uint16_t reg)
{
        usb_device_request_t req;
        usbd_status error;
        uint16_t val;

        req.bmRequestType = UT_READ_VENDOR_DEVICE;
        req.bRequest = RAL_READ_MAC;
        USETW(req.wValue, 0);
        USETW(req.wIndex, reg);
        USETW(req.wLength, sizeof (uint16_t));

        error = usbd_do_request(sc->sc_udev, &req, &val);
        if (error != 0) {
                printf("%s: could not read MAC register: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
                return 0;
        }
        return letoh16(val);
}

void
ural_read_multi(struct ural_softc *sc, uint16_t reg, void *buf, int len)
{
        usb_device_request_t req;
        usbd_status error;

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

        error = usbd_do_request(sc->sc_udev, &req, buf);
        if (error != 0) {
                printf("%s: could not read MAC register: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
        }
}

void
ural_write(struct ural_softc *sc, uint16_t reg, uint16_t val)
{
        usb_device_request_t req;
        usbd_status error;

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

        error = usbd_do_request(sc->sc_udev, &req, NULL);
        if (error != 0) {
                printf("%s: could not write MAC register: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
        }
}

void
ural_write_multi(struct ural_softc *sc, uint16_t reg, void *buf, int len)
{
        usb_device_request_t req;
        usbd_status error;

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

        error = usbd_do_request(sc->sc_udev, &req, buf);
        if (error != 0) {
                printf("%s: could not write MAC register: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
        }
}

void
ural_bbp_write(struct ural_softc *sc, uint8_t reg, uint8_t val)
{
        uint16_t tmp;
        int ntries;

        for (ntries = 0; ntries < 5; ntries++) {
                if (!(ural_read(sc, RAL_PHY_CSR8) & RAL_BBP_BUSY))
                        break;
        }
        if (ntries == 5) {
                printf("%s: could not write to BBP\n", sc->sc_dev.dv_xname);
                return;
        }

        tmp = reg << 8 | val;
        ural_write(sc, RAL_PHY_CSR7, tmp);
}

uint8_t
ural_bbp_read(struct ural_softc *sc, uint8_t reg)
{
        uint16_t val;
        int ntries;

        val = RAL_BBP_WRITE | reg << 8;
        ural_write(sc, RAL_PHY_CSR7, val);

        for (ntries = 0; ntries < 5; ntries++) {
                if (!(ural_read(sc, RAL_PHY_CSR8) & RAL_BBP_BUSY))
                        break;
        }
        if (ntries == 5) {
                printf("%s: could not read BBP\n", sc->sc_dev.dv_xname);
                return 0;
        }
        return ural_read(sc, RAL_PHY_CSR7) & 0xff;
}

void
ural_rf_write(struct ural_softc *sc, uint8_t reg, uint32_t val)
{
        uint32_t tmp;
        int ntries;

        for (ntries = 0; ntries < 5; ntries++) {
                if (!(ural_read(sc, RAL_PHY_CSR10) & RAL_RF_LOBUSY))
                        break;
        }
        if (ntries == 5) {
                printf("%s: could not write to RF\n", sc->sc_dev.dv_xname);
                return;
        }

        tmp = RAL_RF_BUSY | RAL_RF_20BIT | (val & 0xfffff) << 2 | (reg & 0x3);
        ural_write(sc, RAL_PHY_CSR9,  tmp & 0xffff);
        ural_write(sc, RAL_PHY_CSR10, tmp >> 16);

        /* remember last written value in sc */
        sc->rf_regs[reg] = val;

        DPRINTFN(15, ("RF R[%u] <- 0x%05x\n", reg & 0x3, val & 0xfffff));
}

void
ural_set_chan(struct ural_softc *sc, struct ieee80211_channel *c)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint8_t power, tmp;
        u_int chan;

        chan = ieee80211_chan2ieee(ic, c);
        if (chan == 0 || chan == IEEE80211_CHAN_ANY)
                return;

        power = min(sc->txpow[chan - 1], 31);

        DPRINTFN(2, ("setting channel to %u, txpower to %u\n", chan, power));

        switch (sc->rf_rev) {
        case RAL_RF_2522:
                ural_rf_write(sc, RAL_RF1, 0x00814);
                ural_rf_write(sc, RAL_RF2, ural_rf2522_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x00040);
                break;

        case RAL_RF_2523:
                ural_rf_write(sc, RAL_RF1, 0x08804);
                ural_rf_write(sc, RAL_RF2, ural_rf2523_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x38044);
                ural_rf_write(sc, RAL_RF4, (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RAL_RF_2524:
                ural_rf_write(sc, RAL_RF1, 0x0c808);
                ural_rf_write(sc, RAL_RF2, ural_rf2524_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x00040);
                ural_rf_write(sc, RAL_RF4, (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RAL_RF_2525:
                ural_rf_write(sc, RAL_RF1, 0x08808);
                ural_rf_write(sc, RAL_RF2, ural_rf2525_hi_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x18044);
                ural_rf_write(sc, RAL_RF4, (chan == 14) ? 0x00280 : 0x00286);

                ural_rf_write(sc, RAL_RF1, 0x08808);
                ural_rf_write(sc, RAL_RF2, ural_rf2525_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x18044);
                ural_rf_write(sc, RAL_RF4, (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RAL_RF_2525E:
                ural_rf_write(sc, RAL_RF1, 0x08808);
                ural_rf_write(sc, RAL_RF2, ural_rf2525e_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x18044);
                ural_rf_write(sc, RAL_RF4, (chan == 14) ? 0x00286 : 0x00282);
                break;

        case RAL_RF_2526:
                ural_rf_write(sc, RAL_RF2, ural_rf2526_hi_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF4, (chan & 1) ? 0x00386 : 0x00381);
                ural_rf_write(sc, RAL_RF1, 0x08804);

                ural_rf_write(sc, RAL_RF2, ural_rf2526_r2[chan - 1]);
                ural_rf_write(sc, RAL_RF3, power << 7 | 0x18044);
                ural_rf_write(sc, RAL_RF4, (chan & 1) ? 0x00386 : 0x00381);
                break;
        }

        if (ic->ic_opmode != IEEE80211_M_MONITOR &&
            ic->ic_state != IEEE80211_S_SCAN) {
                /* set Japan filter bit for channel 14 */
                tmp = ural_bbp_read(sc, 70);

                tmp &= ~RAL_JAPAN_FILTER;
                if (chan == 14)
                        tmp |= RAL_JAPAN_FILTER;

                ural_bbp_write(sc, 70, tmp);

                /* clear CRC errors */
                ural_read(sc, RAL_STA_CSR0);

                DELAY(1000); /* RF needs a 1ms delay here */
                ural_disable_rf_tune(sc);
        }
}

/*
 * Disable RF auto-tuning.
 */
void
ural_disable_rf_tune(struct ural_softc *sc)
{
        uint32_t tmp;

        if (sc->rf_rev != RAL_RF_2523) {
                tmp = sc->rf_regs[RAL_RF1] & ~RAL_RF1_AUTOTUNE;
                ural_rf_write(sc, RAL_RF1, tmp);
        }

        tmp = sc->rf_regs[RAL_RF3] & ~RAL_RF3_AUTOTUNE;
        ural_rf_write(sc, RAL_RF3, tmp);

        DPRINTFN(2, ("disabling RF autotune\n"));
}

/*
 * Refer to IEEE Std 802.11-1999 pp. 123 for more information on TSF
 * synchronization.
 */
void
ural_enable_tsf_sync(struct ural_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t logcwmin, preload, tmp;

        /* first, disable TSF synchronization */
        ural_write(sc, RAL_TXRX_CSR19, 0);

        tmp = (16 * ic->ic_bss->ni_intval) << 4;
        ural_write(sc, RAL_TXRX_CSR18, tmp);

#ifndef IEEE80211_STA_ONLY
        if (ic->ic_opmode == IEEE80211_M_IBSS) {
                logcwmin = 2;
                preload = 320;
        } else
#endif
        {
                logcwmin = 0;
                preload = 6;
        }
        tmp = logcwmin << 12 | preload;
        ural_write(sc, RAL_TXRX_CSR20, tmp);

        /* finally, enable TSF synchronization */
        tmp = RAL_ENABLE_TSF | RAL_ENABLE_TBCN;
        if (ic->ic_opmode == IEEE80211_M_STA)
                tmp |= RAL_ENABLE_TSF_SYNC(1);
#ifndef IEEE80211_STA_ONLY
        else
                tmp |= RAL_ENABLE_TSF_SYNC(2) | RAL_ENABLE_BEACON_GENERATOR;
#endif
        ural_write(sc, RAL_TXRX_CSR19, tmp);

        DPRINTF(("enabling TSF synchronization\n"));
}

void
ural_update_slot(struct ural_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t slottime, sifs, eifs;

        slottime = (ic->ic_flags & IEEE80211_F_SHSLOT) ?
            IEEE80211_DUR_DS_SHSLOT : IEEE80211_DUR_DS_SLOT;

        /*
         * These settings may sound a bit inconsistent but this is what the
         * reference driver does.
         */
        if (ic->ic_curmode == IEEE80211_MODE_11B) {
                sifs = 16 - RAL_RXTX_TURNAROUND;
                eifs = 364;
        } else {
                sifs = 10 - RAL_RXTX_TURNAROUND;
                eifs = 64;
        }

        ural_write(sc, RAL_MAC_CSR10, slottime);
        ural_write(sc, RAL_MAC_CSR11, sifs);
        ural_write(sc, RAL_MAC_CSR12, eifs);
}

void
ural_set_txpreamble(struct ural_softc *sc)
{
        uint16_t tmp;

        tmp = ural_read(sc, RAL_TXRX_CSR10);

        tmp &= ~RAL_SHORT_PREAMBLE;
        if (sc->sc_ic.ic_flags & IEEE80211_F_SHPREAMBLE)
                tmp |= RAL_SHORT_PREAMBLE;

        ural_write(sc, RAL_TXRX_CSR10, tmp);
}

void
ural_set_basicrates(struct ural_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;

        /* update basic rate set */
        if (ic->ic_curmode == IEEE80211_MODE_11B) {
                /* 11b basic rates: 1, 2Mbps */
                ural_write(sc, RAL_TXRX_CSR11, 0x3);
        } else {
                /* 11b/g basic rates: 1, 2, 5.5, 11Mbps */
                ural_write(sc, RAL_TXRX_CSR11, 0xf);
        }
}

void
ural_set_bssid(struct ural_softc *sc, const uint8_t *bssid)
{
        uint16_t tmp;

        tmp = bssid[0] | bssid[1] << 8;
        ural_write(sc, RAL_MAC_CSR5, tmp);

        tmp = bssid[2] | bssid[3] << 8;
        ural_write(sc, RAL_MAC_CSR6, tmp);

        tmp = bssid[4] | bssid[5] << 8;
        ural_write(sc, RAL_MAC_CSR7, tmp);

        DPRINTF(("setting BSSID to %s\n", ether_sprintf((uint8_t *)bssid)));
}

void
ural_set_macaddr(struct ural_softc *sc, const uint8_t *addr)
{
        uint16_t tmp;

        tmp = addr[0] | addr[1] << 8;
        ural_write(sc, RAL_MAC_CSR2, tmp);

        tmp = addr[2] | addr[3] << 8;
        ural_write(sc, RAL_MAC_CSR3, tmp);

        tmp = addr[4] | addr[5] << 8;
        ural_write(sc, RAL_MAC_CSR4, tmp);

        DPRINTF(("setting MAC address to %s\n",
            ether_sprintf((uint8_t *)addr)));
}

void
ural_update_promisc(struct ural_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ic.ic_if;
        uint16_t tmp;

        tmp = ural_read(sc, RAL_TXRX_CSR2);

        tmp &= ~RAL_DROP_NOT_TO_ME;
        if (!(ifp->if_flags & IFF_PROMISC))
                tmp |= RAL_DROP_NOT_TO_ME;

        ural_write(sc, RAL_TXRX_CSR2, tmp);

        DPRINTF(("%s promiscuous mode\n", (ifp->if_flags & IFF_PROMISC) ?
            "entering" : "leaving"));
}

const char *
ural_get_rf(int rev)
{
        switch (rev) {
        case RAL_RF_2522:       return "RT2522";
        case RAL_RF_2523:       return "RT2523";
        case RAL_RF_2524:       return "RT2524";
        case RAL_RF_2525:       return "RT2525";
        case RAL_RF_2525E:      return "RT2525e";
        case RAL_RF_2526:       return "RT2526";
        case RAL_RF_5222:       return "RT5222";
        default:                return "unknown";
        }
}

void
ural_read_eeprom(struct ural_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t val;

        /* retrieve MAC/BBP type */
        ural_eeprom_read(sc, RAL_EEPROM_MACBBP, &val, 2);
        sc->macbbp_rev = letoh16(val);

        ural_eeprom_read(sc, RAL_EEPROM_CONFIG0, &val, 2);
        val = letoh16(val);
        sc->rf_rev =   (val >> 11) & 0x7;
        sc->hw_radio = (val >> 10) & 0x1;
        sc->led_mode = (val >> 6)  & 0x7;
        sc->rx_ant =   (val >> 4)  & 0x3;
        sc->tx_ant =   (val >> 2)  & 0x3;
        sc->nb_ant =   val & 0x3;

        /* read MAC address */
        ural_eeprom_read(sc, RAL_EEPROM_ADDRESS, ic->ic_myaddr, 6);

        /* read default values for BBP registers */
        ural_eeprom_read(sc, RAL_EEPROM_BBP_BASE, sc->bbp_prom, 2 * 16);

        /* read Tx power for all b/g channels */
        ural_eeprom_read(sc, RAL_EEPROM_TXPOWER, sc->txpow, 14);
}

int
ural_bbp_init(struct ural_softc *sc)
{
        int i, ntries;

        /* wait for BBP to be ready */
        for (ntries = 0; ntries < 100; ntries++) {
                if (ural_bbp_read(sc, RAL_BBP_VERSION) != 0)
                        break;
                DELAY(1000);
        }
        if (ntries == 100) {
                printf("%s: timeout waiting for BBP\n", sc->sc_dev.dv_xname);
                return EIO;
        }

        /* initialize BBP registers to default values */
        for (i = 0; i < nitems(ural_def_bbp); i++)
                ural_bbp_write(sc, ural_def_bbp[i].reg, ural_def_bbp[i].val);

#if 0
        /* initialize BBP registers to values stored in EEPROM */
        for (i = 0; i < 16; i++) {
                if (sc->bbp_prom[i].reg == 0xff)
                        continue;
                ural_bbp_write(sc, sc->bbp_prom[i].reg, sc->bbp_prom[i].val);
        }
#endif

        return 0;
}

void
ural_set_txantenna(struct ural_softc *sc, int antenna)
{
        uint16_t tmp;
        uint8_t tx;

        tx = ural_bbp_read(sc, RAL_BBP_TX) & ~RAL_BBP_ANTMASK;
        if (antenna == 1)
                tx |= RAL_BBP_ANTA;
        else if (antenna == 2)
                tx |= RAL_BBP_ANTB;
        else
                tx |= RAL_BBP_DIVERSITY;

        /* need to force I/Q flip for RF 2525e, 2526 and 5222 */
        if (sc->rf_rev == RAL_RF_2525E || sc->rf_rev == RAL_RF_2526 ||
            sc->rf_rev == RAL_RF_5222)
                tx |= RAL_BBP_FLIPIQ;

        ural_bbp_write(sc, RAL_BBP_TX, tx);

        /* update flags in PHY_CSR5 and PHY_CSR6 too */
        tmp = ural_read(sc, RAL_PHY_CSR5) & ~0x7;
        ural_write(sc, RAL_PHY_CSR5, tmp | (tx & 0x7));

        tmp = ural_read(sc, RAL_PHY_CSR6) & ~0x7;
        ural_write(sc, RAL_PHY_CSR6, tmp | (tx & 0x7));
}

void
ural_set_rxantenna(struct ural_softc *sc, int antenna)
{
        uint8_t rx;

        rx = ural_bbp_read(sc, RAL_BBP_RX) & ~RAL_BBP_ANTMASK;
        if (antenna == 1)
                rx |= RAL_BBP_ANTA;
        else if (antenna == 2)
                rx |= RAL_BBP_ANTB;
        else
                rx |= RAL_BBP_DIVERSITY;

        /* need to force no I/Q flip for RF 2525e and 2526 */
        if (sc->rf_rev == RAL_RF_2525E || sc->rf_rev == RAL_RF_2526)
                rx &= ~RAL_BBP_FLIPIQ;

        ural_bbp_write(sc, RAL_BBP_RX, rx);
}

int
ural_init(struct ifnet *ifp)
{
        struct ural_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t tmp;
        usbd_status error;
        int i, ntries;

        ural_stop(ifp, 0);

        /* initialize MAC registers to default values */
        for (i = 0; i < nitems(ural_def_mac); i++)
                ural_write(sc, ural_def_mac[i].reg, ural_def_mac[i].val);

        /* wait for BBP and RF to wake up (this can take a long time!) */
        for (ntries = 0; ntries < 100; ntries++) {
                tmp = ural_read(sc, RAL_MAC_CSR17);
                if ((tmp & (RAL_BBP_AWAKE | RAL_RF_AWAKE)) ==
                    (RAL_BBP_AWAKE | RAL_RF_AWAKE))
                        break;
                DELAY(1000);
        }
        if (ntries == 100) {
                printf("%s: timeout waiting for BBP/RF to wakeup\n",
                    sc->sc_dev.dv_xname);
                error = EIO;
                goto fail;
        }

        /* we're ready! */
        ural_write(sc, RAL_MAC_CSR1, RAL_HOST_READY);

        /* set basic rate set (will be updated later) */
        ural_write(sc, RAL_TXRX_CSR11, 0x153);

        error = ural_bbp_init(sc);
        if (error != 0)
                goto fail;

        /* set default BSS channel */
        ic->ic_bss->ni_chan = ic->ic_ibss_chan;
        ural_set_chan(sc, ic->ic_bss->ni_chan);

        /* clear statistic registers (STA_CSR0 to STA_CSR10) */
        ural_read_multi(sc, RAL_STA_CSR0, sc->sta, sizeof sc->sta);

        /* set default sensitivity */
        ural_bbp_write(sc, 17, 0x48);

        ural_set_txantenna(sc, 1);
        ural_set_rxantenna(sc, 1);

        IEEE80211_ADDR_COPY(ic->ic_myaddr, LLADDR(ifp->if_sadl));
        ural_set_macaddr(sc, ic->ic_myaddr);

        /*
         * Copy WEP keys into adapter's memory (SEC_CSR0 to SEC_CSR31).
         */
        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                struct ieee80211_key *k = &ic->ic_nw_keys[i];
                ural_write_multi(sc, RAL_SEC_CSR0 + i * IEEE80211_KEYBUF_SIZE,
                    k->k_key, IEEE80211_KEYBUF_SIZE);
        }

        /*
         * Allocate xfer for AMRR statistics requests.
         */
        sc->amrr_xfer = usbd_alloc_xfer(sc->sc_udev);
        if (sc->amrr_xfer == NULL) {
                printf("%s: could not allocate AMRR xfer\n",
                    sc->sc_dev.dv_xname);
                goto fail;
        }

        /*
         * Open Tx and Rx USB bulk pipes.
         */
        error = usbd_open_pipe(sc->sc_iface, sc->sc_tx_no, USBD_EXCLUSIVE_USE,
            &sc->sc_tx_pipeh);
        if (error != 0) {
                printf("%s: could not open Tx pipe: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
                goto fail;
        }
        error = usbd_open_pipe(sc->sc_iface, sc->sc_rx_no, USBD_EXCLUSIVE_USE,
            &sc->sc_rx_pipeh);
        if (error != 0) {
                printf("%s: could not open Rx pipe: %s\n",
                    sc->sc_dev.dv_xname, usbd_errstr(error));
                goto fail;
        }

        /*
         * Allocate Tx and Rx xfer queues.
         */
        error = ural_alloc_tx_list(sc);
        if (error != 0) {
                printf("%s: could not allocate Tx list\n",
                    sc->sc_dev.dv_xname);
                goto fail;
        }
        error = ural_alloc_rx_list(sc);
        if (error != 0) {
                printf("%s: could not allocate Rx list\n",
                    sc->sc_dev.dv_xname);
                goto fail;
        }

        /*
         * Start up the receive pipe.
         */
        for (i = 0; i < RAL_RX_LIST_COUNT; i++) {
                struct ural_rx_data *data = &sc->rx_data[i];

                usbd_setup_xfer(data->xfer, sc->sc_rx_pipeh, data, data->buf,
                    MCLBYTES, USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, ural_rxeof);
                error = usbd_transfer(data->xfer);
                if (error != 0 && error != USBD_IN_PROGRESS) {
                        printf("%s: could not queue Rx transfer\n",
                            sc->sc_dev.dv_xname);
                        goto fail;
                }
        }

        /* kick Rx */
        tmp = RAL_DROP_PHY_ERROR | RAL_DROP_CRC_ERROR;
        if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                tmp |= RAL_DROP_CTL | RAL_DROP_VERSION_ERROR;
#ifndef IEEE80211_STA_ONLY
                if (ic->ic_opmode != IEEE80211_M_HOSTAP)
#endif
                        tmp |= RAL_DROP_TODS;
                if (!(ifp->if_flags & IFF_PROMISC))
                        tmp |= RAL_DROP_NOT_TO_ME;
        }
        ural_write(sc, RAL_TXRX_CSR2, tmp);

        ifq_clr_oactive(&ifp->if_snd);
        ifp->if_flags |= IFF_RUNNING;

        if (ic->ic_opmode == IEEE80211_M_MONITOR)
                ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
        else
                ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);

        return 0;

fail:   ural_stop(ifp, 1);
        return error;
}

void
ural_stop(struct ifnet *ifp, int disable)
{
        struct ural_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;

        sc->sc_tx_timer = 0;
        ifp->if_timer = 0;
        ifp->if_flags &= ~IFF_RUNNING;
        ifq_clr_oactive(&ifp->if_snd);

        ieee80211_new_state(ic, IEEE80211_S_INIT, -1);  /* free all nodes */

        /* disable Rx */
        ural_write(sc, RAL_TXRX_CSR2, RAL_DISABLE_RX);

        /* reset ASIC and BBP (but won't reset MAC registers!) */
        ural_write(sc, RAL_MAC_CSR1, RAL_RESET_ASIC | RAL_RESET_BBP);
        ural_write(sc, RAL_MAC_CSR1, 0);

        if (sc->amrr_xfer != NULL) {
                usbd_free_xfer(sc->amrr_xfer);
                sc->amrr_xfer = NULL;
        }
        if (sc->sc_rx_pipeh != NULL) {
                usbd_close_pipe(sc->sc_rx_pipeh);
                sc->sc_rx_pipeh = NULL;
        }
        if (sc->sc_tx_pipeh != NULL) {
                usbd_close_pipe(sc->sc_tx_pipeh);
                sc->sc_tx_pipeh = NULL;
        }

        ural_free_rx_list(sc);
        ural_free_tx_list(sc);
}

void
ural_newassoc(struct ieee80211com *ic, struct ieee80211_node *ni, int isnew)
{
        /* start with lowest Tx rate */
        ni->ni_txrate = 0;
}

void
ural_amrr_start(struct ural_softc *sc, struct ieee80211_node *ni)
{
        int i;

        /* clear statistic registers (STA_CSR0 to STA_CSR10) */
        ural_read_multi(sc, RAL_STA_CSR0, sc->sta, sizeof sc->sta);

        ieee80211_amrr_node_init(&sc->amrr, &sc->amn);

        /* set rate to some reasonable initial value */
        for (i = ni->ni_rates.rs_nrates - 1;
             i > 0 && (ni->ni_rates.rs_rates[i] & IEEE80211_RATE_VAL) > 72;
             i--);
        ni->ni_txrate = i;

        if (!usbd_is_dying(sc->sc_udev))
                timeout_add_sec(&sc->amrr_to, 1);
}

void
ural_amrr_timeout(void *arg)
{
        struct ural_softc *sc = arg;
        usb_device_request_t req;
        int s;

        if (usbd_is_dying(sc->sc_udev))
                return;

        usbd_ref_incr(sc->sc_udev);

        s = splusb();

        /*
         * Asynchronously read statistic registers (cleared by read).
         */
        req.bmRequestType = UT_READ_VENDOR_DEVICE;
        req.bRequest = RAL_READ_MULTI_MAC;
        USETW(req.wValue, 0);
        USETW(req.wIndex, RAL_STA_CSR0);
        USETW(req.wLength, sizeof sc->sta);

        usbd_setup_default_xfer(sc->amrr_xfer, sc->sc_udev, sc,
            USBD_DEFAULT_TIMEOUT, &req, sc->sta, sizeof sc->sta, 0,
            ural_amrr_update);
        (void)usbd_transfer(sc->amrr_xfer);

        splx(s);

        usbd_ref_decr(sc->sc_udev);
}

void
ural_amrr_update(struct usbd_xfer *xfer, void *priv,
    usbd_status status)
{
        struct ural_softc *sc = (struct ural_softc *)priv;
        struct ifnet *ifp = &sc->sc_ic.ic_if;

        if (status != USBD_NORMAL_COMPLETION) {
                printf("%s: could not retrieve Tx statistics - cancelling "
                    "automatic rate control\n", sc->sc_dev.dv_xname);
                return;
        }

        /* count TX retry-fail as Tx errors */
        ifp->if_oerrors += letoh16(sc->sta[9]);

        sc->amn.amn_retrycnt =
            letoh16(sc->sta[7]) +       /* TX one-retry ok count */
            letoh16(sc->sta[8]) +       /* TX more-retry ok count */
            letoh16(sc->sta[9]);        /* TX retry-fail count */

        sc->amn.amn_txcnt =
            sc->amn.amn_retrycnt +
            letoh16(sc->sta[6]);        /* TX no-retry ok count */

        ieee80211_amrr_choose(&sc->amrr, sc->sc_ic.ic_bss, &sc->amn);

        if (!usbd_is_dying(sc->sc_udev))
                timeout_add_sec(&sc->amrr_to, 1);
}