ubsa.c

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/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD AND BSD-2-Clause-NetBSD
 *
 * Copyright (c) 2002, Alexander Kabaev <kan.FreeBSD.org>.
 * 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.
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*-
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Ichiro FUKUHARA (ichiro@ichiro.org).
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */
 
#include <sys/stdint.h>
#include <sys/stddef.h>
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/sysctl.h>
#include <sys/sx.h>
#include <sys/unistd.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/priv.h>
 
#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>
#include "usbdevs.h"
 
#define USB_DEBUG_VAR ubsa_debug
#include <dev/usb/usb_debug.h>
#include <dev/usb/usb_process.h>
 
#include <dev/usb/serial/usb_serial.h>
 
#ifdef USB_DEBUG
static int ubsa_debug = 0;
 
static SYSCTL_NODE(_hw_usb, OID_AUTO, ubsa, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "USB ubsa");
SYSCTL_INT(_hw_usb_ubsa, OID_AUTO, debug, CTLFLAG_RWTUN,
    &ubsa_debug, 0, "ubsa debug level");
#endif
 
#define UBSA_BSIZE             1024     /* bytes */
 
#define UBSA_CONFIG_INDEX       0
#define UBSA_IFACE_INDEX        0
 
#define UBSA_REG_BAUDRATE       0x00
#define UBSA_REG_STOP_BITS      0x01
#define UBSA_REG_DATA_BITS      0x02
#define UBSA_REG_PARITY         0x03
#define UBSA_REG_DTR            0x0A
#define UBSA_REG_RTS            0x0B
#define UBSA_REG_BREAK          0x0C
#define UBSA_REG_FLOW_CTRL      0x10
 
#define UBSA_PARITY_NONE        0x00
#define UBSA_PARITY_EVEN        0x01
#define UBSA_PARITY_ODD         0x02
#define UBSA_PARITY_MARK        0x03
#define UBSA_PARITY_SPACE       0x04
 
#define UBSA_FLOW_NONE          0x0000
#define UBSA_FLOW_OCTS          0x0001
#define UBSA_FLOW_ODSR          0x0002
#define UBSA_FLOW_IDSR          0x0004
#define UBSA_FLOW_IDTR          0x0008
#define UBSA_FLOW_IRTS          0x0010
#define UBSA_FLOW_ORTS          0x0020
#define UBSA_FLOW_UNKNOWN       0x0040
#define UBSA_FLOW_OXON          0x0080
#define UBSA_FLOW_IXON          0x0100
 
/* line status register */
#define UBSA_LSR_TSRE           0x40    /* Transmitter empty: byte sent */
#define UBSA_LSR_TXRDY          0x20    /* Transmitter buffer empty */
#define UBSA_LSR_BI             0x10    /* Break detected */
#define UBSA_LSR_FE             0x08    /* Framing error: bad stop bit */
#define UBSA_LSR_PE             0x04    /* Parity error */
#define UBSA_LSR_OE             0x02    /* Overrun, lost incoming byte */
#define UBSA_LSR_RXRDY          0x01    /* Byte ready in Receive Buffer */
#define UBSA_LSR_RCV_MASK       0x1f    /* Mask for incoming data or error */
 
/* modem status register */
/* All deltas are from the last read of the MSR. */
#define UBSA_MSR_DCD            0x80    /* Current Data Carrier Detect */
#define UBSA_MSR_RI             0x40    /* Current Ring Indicator */
#define UBSA_MSR_DSR            0x20    /* Current Data Set Ready */
#define UBSA_MSR_CTS            0x10    /* Current Clear to Send */
#define UBSA_MSR_DDCD           0x08    /* DCD has changed state */
#define UBSA_MSR_TERI           0x04    /* RI has toggled low to high */
#define UBSA_MSR_DDSR           0x02    /* DSR has changed state */
#define UBSA_MSR_DCTS           0x01    /* CTS has changed state */
 
enum {
        UBSA_BULK_DT_WR,
        UBSA_BULK_DT_RD,
        UBSA_INTR_DT_RD,
        UBSA_N_TRANSFER,
};
 
struct ubsa_softc {
        struct ucom_super_softc sc_super_ucom;
        struct ucom_softc sc_ucom;
 
        struct usb_xfer *sc_xfer[UBSA_N_TRANSFER];
        struct usb_device *sc_udev;
        struct mtx sc_mtx;
 
        uint8_t sc_iface_no;            /* interface number */
        uint8_t sc_iface_index;         /* interface index */
        uint8_t sc_lsr;                 /* local status register */
        uint8_t sc_msr;                 /* UBSA status register */
};
 
static device_probe_t ubsa_probe;
static device_attach_t ubsa_attach;
static device_detach_t ubsa_detach;
static void ubsa_free_softc(struct ubsa_softc *);
 
static usb_callback_t ubsa_write_callback;
static usb_callback_t ubsa_read_callback;
static usb_callback_t ubsa_intr_callback;
 
static void     ubsa_cfg_request(struct ubsa_softc *, uint8_t, uint16_t);
static void     ubsa_free(struct ucom_softc *);
static void     ubsa_cfg_set_dtr(struct ucom_softc *, uint8_t);
static void     ubsa_cfg_set_rts(struct ucom_softc *, uint8_t);
static void     ubsa_cfg_set_break(struct ucom_softc *, uint8_t);
static int      ubsa_pre_param(struct ucom_softc *, struct termios *);
static void     ubsa_cfg_param(struct ucom_softc *, struct termios *);
static void     ubsa_start_read(struct ucom_softc *);
static void     ubsa_stop_read(struct ucom_softc *);
static void     ubsa_start_write(struct ucom_softc *);
static void     ubsa_stop_write(struct ucom_softc *);
static void     ubsa_cfg_get_status(struct ucom_softc *, uint8_t *,
                    uint8_t *);
static void     ubsa_poll(struct ucom_softc *ucom);
 
static const struct usb_config ubsa_config[UBSA_N_TRANSFER] = {
        [UBSA_BULK_DT_WR] = {
                .type = UE_BULK,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_OUT,
                .bufsize = UBSA_BSIZE,  /* bytes */
                .flags = {.pipe_bof = 1,.force_short_xfer = 1,},
                .callback = &ubsa_write_callback,
        },
 
        [UBSA_BULK_DT_RD] = {
                .type = UE_BULK,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_IN,
                .bufsize = UBSA_BSIZE,  /* bytes */
                .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                .callback = &ubsa_read_callback,
        },
 
        [UBSA_INTR_DT_RD] = {
                .type = UE_INTERRUPT,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_IN,
                .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                .bufsize = 0,   /* use wMaxPacketSize */
                .callback = &ubsa_intr_callback,
        },
};
 
static const struct ucom_callback ubsa_callback = {
        .ucom_cfg_get_status = &ubsa_cfg_get_status,
        .ucom_cfg_set_dtr = &ubsa_cfg_set_dtr,
        .ucom_cfg_set_rts = &ubsa_cfg_set_rts,
        .ucom_cfg_set_break = &ubsa_cfg_set_break,
        .ucom_cfg_param = &ubsa_cfg_param,
        .ucom_pre_param = &ubsa_pre_param,
        .ucom_start_read = &ubsa_start_read,
        .ucom_stop_read = &ubsa_stop_read,
        .ucom_start_write = &ubsa_start_write,
        .ucom_stop_write = &ubsa_stop_write,
        .ucom_poll = &ubsa_poll,
        .ucom_free = &ubsa_free,
};
 
static const STRUCT_USB_HOST_ID ubsa_devs[] = {
        /* AnyData ADU-500A */
        {USB_VPI(USB_VENDOR_ANYDATA, USB_PRODUCT_ANYDATA_ADU_500A, 0)},
        /* AnyData ADU-E100A/H */
        {USB_VPI(USB_VENDOR_ANYDATA, USB_PRODUCT_ANYDATA_ADU_E100X, 0)},
        /* Axesstel MV100H */
        {USB_VPI(USB_VENDOR_AXESSTEL, USB_PRODUCT_AXESSTEL_DATAMODEM, 0)},
        /* BELKIN F5U103 */
        {USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U103, 0)},
        /* BELKIN F5U120 */
        {USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U120, 0)},
        /* GoHubs GO-COM232 */
        {USB_VPI(USB_VENDOR_ETEK, USB_PRODUCT_ETEK_1COM, 0)},
        /* GoHubs GO-COM232 */
        {USB_VPI(USB_VENDOR_GOHUBS, USB_PRODUCT_GOHUBS_GOCOM232, 0)},
        /* Peracom */
        {USB_VPI(USB_VENDOR_PERACOM, USB_PRODUCT_PERACOM_SERIAL1, 0)},
};
 
static device_method_t ubsa_methods[] = {
        DEVMETHOD(device_probe, ubsa_probe),
        DEVMETHOD(device_attach, ubsa_attach),
        DEVMETHOD(device_detach, ubsa_detach),
        DEVMETHOD_END
};
 
static devclass_t ubsa_devclass;
 
static driver_t ubsa_driver = {
        .name = "ubsa",
        .methods = ubsa_methods,
        .size = sizeof(struct ubsa_softc),
};
 
DRIVER_MODULE(ubsa, uhub, ubsa_driver, ubsa_devclass, NULL, 0);
MODULE_DEPEND(ubsa, ucom, 1, 1, 1);
MODULE_DEPEND(ubsa, usb, 1, 1, 1);
MODULE_VERSION(ubsa, 1);
USB_PNP_HOST_INFO(ubsa_devs);
 
static int
ubsa_probe(device_t dev)
{
        struct usb_attach_arg *uaa = device_get_ivars(dev);
 
        if (uaa->usb_mode != USB_MODE_HOST) {
                return (ENXIO);
        }
        if (uaa->info.bConfigIndex != UBSA_CONFIG_INDEX) {
                return (ENXIO);
        }
        if (uaa->info.bIfaceIndex != UBSA_IFACE_INDEX) {
                return (ENXIO);
        }
        return (usbd_lookup_id_by_uaa(ubsa_devs, sizeof(ubsa_devs), uaa));
}
 
static int
ubsa_attach(device_t dev)
{
        struct usb_attach_arg *uaa = device_get_ivars(dev);
        struct ubsa_softc *sc = device_get_softc(dev);
        int error;
 
        DPRINTF("sc=%p\n", sc);
 
        device_set_usb_desc(dev);
        mtx_init(&sc->sc_mtx, "ubsa", NULL, MTX_DEF);
        ucom_ref(&sc->sc_super_ucom);
 
        sc->sc_udev = uaa->device;
        sc->sc_iface_no = uaa->info.bIfaceNum;
        sc->sc_iface_index = UBSA_IFACE_INDEX;
 
        error = usbd_transfer_setup(uaa->device, &sc->sc_iface_index,
            sc->sc_xfer, ubsa_config, UBSA_N_TRANSFER, sc, &sc->sc_mtx);
 
        if (error) {
                DPRINTF("could not allocate all pipes\n");
                goto detach;
        }
        /* clear stall at first run */
        mtx_lock(&sc->sc_mtx);
        usbd_xfer_set_stall(sc->sc_xfer[UBSA_BULK_DT_WR]);
        usbd_xfer_set_stall(sc->sc_xfer[UBSA_BULK_DT_RD]);
        mtx_unlock(&sc->sc_mtx);
 
        error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
            &ubsa_callback, &sc->sc_mtx);
        if (error) {
                DPRINTF("ucom_attach failed\n");
                goto detach;
        }
        ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
 
        return (0);
 
detach:
        ubsa_detach(dev);
        return (ENXIO);
}
 
static int
ubsa_detach(device_t dev)
{
        struct ubsa_softc *sc = device_get_softc(dev);
 
        DPRINTF("sc=%p\n", sc);
 
        ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
        usbd_transfer_unsetup(sc->sc_xfer, UBSA_N_TRANSFER);
 
        device_claim_softc(dev);
 
        ubsa_free_softc(sc);
 
        return (0);
}
 
UCOM_UNLOAD_DRAIN(ubsa);
 
static void
ubsa_free_softc(struct ubsa_softc *sc)
{
        if (ucom_unref(&sc->sc_super_ucom)) {
                mtx_destroy(&sc->sc_mtx);
                device_free_softc(sc);
        }
}
 
static void
ubsa_free(struct ucom_softc *ucom)
{
        ubsa_free_softc(ucom->sc_parent);
}
 
static void
ubsa_cfg_request(struct ubsa_softc *sc, uint8_t index, uint16_t value)
{
        struct usb_device_request req;
        usb_error_t err;
 
        req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
        req.bRequest = index;
        USETW(req.wValue, value);
        req.wIndex[0] = sc->sc_iface_no;
        req.wIndex[1] = 0;
        USETW(req.wLength, 0);
 
        err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom, 
            &req, NULL, 0, 1000);
        if (err) {
                DPRINTFN(0, "device request failed, err=%s "
                    "(ignored)\n", usbd_errstr(err));
        }
}
 
static void
ubsa_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        DPRINTF("onoff = %d\n", onoff);
 
        ubsa_cfg_request(sc, UBSA_REG_DTR, onoff ? 1 : 0);
}
 
static void
ubsa_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        DPRINTF("onoff = %d\n", onoff);
 
        ubsa_cfg_request(sc, UBSA_REG_RTS, onoff ? 1 : 0);
}
 
static void
ubsa_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        DPRINTF("onoff = %d\n", onoff);
 
        ubsa_cfg_request(sc, UBSA_REG_BREAK, onoff ? 1 : 0);
}
 
static int
ubsa_pre_param(struct ucom_softc *ucom, struct termios *t)
{
 
        DPRINTF("sc = %p\n", ucom->sc_parent);
 
        switch (t->c_ospeed) {
        case B0:
        case B300:
        case B600:
        case B1200:
        case B2400:
        case B4800:
        case B9600:
        case B19200:
        case B38400:
        case B57600:
        case B115200:
        case B230400:
                break;
        default:
                return (EINVAL);
        }
        return (0);
}
 
static void
ubsa_cfg_param(struct ucom_softc *ucom, struct termios *t)
{
        struct ubsa_softc *sc = ucom->sc_parent;
        uint16_t value = 0;
 
        DPRINTF("sc = %p\n", sc);
 
        switch (t->c_ospeed) {
        case B0:
                ubsa_cfg_request(sc, UBSA_REG_FLOW_CTRL, 0);
                ubsa_cfg_set_dtr(&sc->sc_ucom, 0);
                ubsa_cfg_set_rts(&sc->sc_ucom, 0);
                break;
        case B300:
        case B600:
        case B1200:
        case B2400:
        case B4800:
        case B9600:
        case B19200:
        case B38400:
        case B57600:
        case B115200:
        case B230400:
                value = B230400 / t->c_ospeed;
                ubsa_cfg_request(sc, UBSA_REG_BAUDRATE, value);
                break;
        default:
                return;
        }
 
        if (t->c_cflag & PARENB)
                value = (t->c_cflag & PARODD) ? UBSA_PARITY_ODD : UBSA_PARITY_EVEN;
        else
                value = UBSA_PARITY_NONE;
 
        ubsa_cfg_request(sc, UBSA_REG_PARITY, value);
 
        switch (t->c_cflag & CSIZE) {
        case CS5:
                value = 0;
                break;
        case CS6:
                value = 1;
                break;
        case CS7:
                value = 2;
                break;
        default:
        case CS8:
                value = 3;
                break;
        }
 
        ubsa_cfg_request(sc, UBSA_REG_DATA_BITS, value);
 
        value = (t->c_cflag & CSTOPB) ? 1 : 0;
 
        ubsa_cfg_request(sc, UBSA_REG_STOP_BITS, value);
 
        value = 0;
        if (t->c_cflag & CRTSCTS)
                value |= UBSA_FLOW_OCTS | UBSA_FLOW_IRTS;
 
        if (t->c_iflag & (IXON | IXOFF))
                value |= UBSA_FLOW_OXON | UBSA_FLOW_IXON;
 
        ubsa_cfg_request(sc, UBSA_REG_FLOW_CTRL, value);
}
 
static void
ubsa_start_read(struct ucom_softc *ucom)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        /* start interrupt endpoint */
        usbd_transfer_start(sc->sc_xfer[UBSA_INTR_DT_RD]);
 
        /* start read endpoint */
        usbd_transfer_start(sc->sc_xfer[UBSA_BULK_DT_RD]);
}
 
static void
ubsa_stop_read(struct ucom_softc *ucom)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        /* stop interrupt endpoint */
        usbd_transfer_stop(sc->sc_xfer[UBSA_INTR_DT_RD]);
 
        /* stop read endpoint */
        usbd_transfer_stop(sc->sc_xfer[UBSA_BULK_DT_RD]);
}
 
static void
ubsa_start_write(struct ucom_softc *ucom)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        usbd_transfer_start(sc->sc_xfer[UBSA_BULK_DT_WR]);
}
 
static void
ubsa_stop_write(struct ucom_softc *ucom)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        usbd_transfer_stop(sc->sc_xfer[UBSA_BULK_DT_WR]);
}
 
static void
ubsa_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
{
        struct ubsa_softc *sc = ucom->sc_parent;
 
        DPRINTF("\n");
 
        *lsr = sc->sc_lsr;
        *msr = sc->sc_msr;
}
 
static void
ubsa_write_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct ubsa_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        uint32_t actlen;
 
        switch (USB_GET_STATE(xfer)) {
        case USB_ST_SETUP:
        case USB_ST_TRANSFERRED:
tr_setup:
                pc = usbd_xfer_get_frame(xfer, 0);
                if (ucom_get_data(&sc->sc_ucom, pc, 0,
                    UBSA_BSIZE, &actlen)) {
                        usbd_xfer_set_frame_len(xfer, 0, actlen);
                        usbd_transfer_submit(xfer);
                }
                return;
 
        default:                        /* Error */
                if (error != USB_ERR_CANCELLED) {
                        /* try to clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                return;
        }
}
 
static void
ubsa_read_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct ubsa_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        int actlen;
 
        usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
 
        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
                pc = usbd_xfer_get_frame(xfer, 0);
                ucom_put_data(&sc->sc_ucom, pc, 0, actlen);
 
        case USB_ST_SETUP:
tr_setup:
                usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                usbd_transfer_submit(xfer);
                return;
 
        default:                        /* Error */
                if (error != USB_ERR_CANCELLED) {
                        /* try to clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                return;
        }
}
 
static void
ubsa_intr_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct ubsa_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        uint8_t buf[4];
        int actlen;
 
        usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
 
        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
 
                if (actlen >= (int)sizeof(buf)) {
                        pc = usbd_xfer_get_frame(xfer, 0);
                        usbd_copy_out(pc, 0, buf, sizeof(buf));
 
                        /*
                         * MSR bits need translation from ns16550 to SER_* values.
                         * LSR bits are ns16550 in hardware and ucom.
                         */
                        sc->sc_msr = 0;
                        if (buf[3] & UBSA_MSR_CTS)
                                sc->sc_msr |= SER_CTS;
                        if (buf[3] & UBSA_MSR_DCD)
                                sc->sc_msr |= SER_DCD;
                        if (buf[3] & UBSA_MSR_RI)
                                sc->sc_msr |= SER_RI;
                        if (buf[3] & UBSA_MSR_DSR)
                                sc->sc_msr |= SER_DSR;
                        sc->sc_lsr = buf[2];
 
                        DPRINTF("lsr = 0x%02x, msr = 0x%02x\n",
                            sc->sc_lsr, sc->sc_msr);
 
                        ucom_status_change(&sc->sc_ucom);
                } else {
                        DPRINTF("ignoring short packet, %d bytes\n", actlen);
                }
                /* FALLTHROUGH */
        case USB_ST_SETUP:
tr_setup:
                usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                usbd_transfer_submit(xfer);
                return;
 
        default:                        /* Error */
                if (error != USB_ERR_CANCELLED) {
                        /* try to clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                return;
        }
}
 
static void
ubsa_poll(struct ucom_softc *ucom)
{
        struct ubsa_softc *sc = ucom->sc_parent;
        usbd_transfer_poll(sc->sc_xfer, UBSA_N_TRANSFER);
 
}