1 /* $NetBSD: usb/uvscom.c,v 1.1 2002/03/19 15:08:42 augustss Exp $ */
7 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
9 * Copyright (c) 2001-2003, 2005 Shunsuke Akiyama <akiyama@jp.FreeBSD.org>.
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * uvscom: SUNTAC Slipper U VS-10U driver.
37 * Slipper U is a PC Card to USB converter for data communication card
38 * adapter. It supports DDI Pocket's Air H" C@rd, C@rd H" 64, NTT's P-in,
39 * P-in m@ater and various data communication card adapters.
42 #include <sys/stdint.h>
43 #include <sys/stddef.h>
44 #include <sys/param.h>
45 #include <sys/queue.h>
46 #include <sys/types.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
50 #include <sys/module.h>
52 #include <sys/mutex.h>
53 #include <sys/condvar.h>
54 #include <sys/sysctl.h>
56 #include <sys/unistd.h>
57 #include <sys/callout.h>
58 #include <sys/malloc.h>
61 #include <dev/usb/usb.h>
62 #include <dev/usb/usbdi.h>
63 #include <dev/usb/usbdi_util.h>
66 #define USB_DEBUG_VAR uvscom_debug
67 #include <dev/usb/usb_debug.h>
68 #include <dev/usb/usb_process.h>
70 #include <dev/usb/serial/usb_serial.h>
73 static int uvscom_debug = 0;
75 static SYSCTL_NODE(_hw_usb, OID_AUTO, uvscom, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
77 SYSCTL_INT(_hw_usb_uvscom, OID_AUTO, debug, CTLFLAG_RWTUN,
78 &uvscom_debug, 0, "Debug level");
81 #define UVSCOM_MODVER 1 /* module version */
83 #define UVSCOM_CONFIG_INDEX 0
84 #define UVSCOM_IFACE_INDEX 0
87 #define UVSCOM_SET_SPEED 0x10
88 #define UVSCOM_LINE_CTL 0x11
89 #define UVSCOM_SET_PARAM 0x12
90 #define UVSCOM_READ_STATUS 0xd0
91 #define UVSCOM_SHUTDOWN 0xe0
93 /* UVSCOM_SET_SPEED parameters */
94 #define UVSCOM_SPEED_150BPS 0x00
95 #define UVSCOM_SPEED_300BPS 0x01
96 #define UVSCOM_SPEED_600BPS 0x02
97 #define UVSCOM_SPEED_1200BPS 0x03
98 #define UVSCOM_SPEED_2400BPS 0x04
99 #define UVSCOM_SPEED_4800BPS 0x05
100 #define UVSCOM_SPEED_9600BPS 0x06
101 #define UVSCOM_SPEED_19200BPS 0x07
102 #define UVSCOM_SPEED_38400BPS 0x08
103 #define UVSCOM_SPEED_57600BPS 0x09
104 #define UVSCOM_SPEED_115200BPS 0x0a
106 /* UVSCOM_LINE_CTL parameters */
107 #define UVSCOM_BREAK 0x40
108 #define UVSCOM_RTS 0x02
109 #define UVSCOM_DTR 0x01
110 #define UVSCOM_LINE_INIT 0x08
112 /* UVSCOM_SET_PARAM parameters */
113 #define UVSCOM_DATA_MASK 0x03
114 #define UVSCOM_DATA_BIT_8 0x03
115 #define UVSCOM_DATA_BIT_7 0x02
116 #define UVSCOM_DATA_BIT_6 0x01
117 #define UVSCOM_DATA_BIT_5 0x00
119 #define UVSCOM_STOP_MASK 0x04
120 #define UVSCOM_STOP_BIT_2 0x04
121 #define UVSCOM_STOP_BIT_1 0x00
123 #define UVSCOM_PARITY_MASK 0x18
124 #define UVSCOM_PARITY_EVEN 0x18
125 #define UVSCOM_PARITY_ODD 0x08
126 #define UVSCOM_PARITY_NONE 0x00
129 #define UVSCOM_TXRDY 0x04
130 #define UVSCOM_RXRDY 0x01
132 #define UVSCOM_DCD 0x08
133 #define UVSCOM_NOCARD 0x04
134 #define UVSCOM_DSR 0x02
135 #define UVSCOM_CTS 0x01
136 #define UVSCOM_USTAT_MASK (UVSCOM_NOCARD | UVSCOM_DSR | UVSCOM_CTS)
138 #define UVSCOM_BULK_BUF_SIZE 1024 /* bytes */
147 struct uvscom_softc {
148 struct ucom_super_softc sc_super_ucom;
149 struct ucom_softc sc_ucom;
151 struct usb_xfer *sc_xfer[UVSCOM_N_TRANSFER];
152 struct usb_device *sc_udev;
155 uint16_t sc_line; /* line control register */
157 uint8_t sc_iface_no; /* interface number */
158 uint8_t sc_iface_index; /* interface index */
159 uint8_t sc_lsr; /* local status register */
160 uint8_t sc_msr; /* uvscom status register */
161 uint8_t sc_unit_status; /* unit status */
166 static device_probe_t uvscom_probe;
167 static device_attach_t uvscom_attach;
168 static device_detach_t uvscom_detach;
169 static void uvscom_free_softc(struct uvscom_softc *);
171 static usb_callback_t uvscom_write_callback;
172 static usb_callback_t uvscom_read_callback;
173 static usb_callback_t uvscom_intr_callback;
175 static void uvscom_free(struct ucom_softc *);
176 static void uvscom_cfg_set_dtr(struct ucom_softc *, uint8_t);
177 static void uvscom_cfg_set_rts(struct ucom_softc *, uint8_t);
178 static void uvscom_cfg_set_break(struct ucom_softc *, uint8_t);
179 static int uvscom_pre_param(struct ucom_softc *, struct termios *);
180 static void uvscom_cfg_param(struct ucom_softc *, struct termios *);
181 static int uvscom_pre_open(struct ucom_softc *);
182 static void uvscom_cfg_open(struct ucom_softc *);
183 static void uvscom_cfg_close(struct ucom_softc *);
184 static void uvscom_start_read(struct ucom_softc *);
185 static void uvscom_stop_read(struct ucom_softc *);
186 static void uvscom_start_write(struct ucom_softc *);
187 static void uvscom_stop_write(struct ucom_softc *);
188 static void uvscom_cfg_get_status(struct ucom_softc *, uint8_t *,
190 static void uvscom_cfg_write(struct uvscom_softc *, uint8_t, uint16_t);
191 static uint16_t uvscom_cfg_read_status(struct uvscom_softc *);
192 static void uvscom_poll(struct ucom_softc *ucom);
194 static const struct usb_config uvscom_config[UVSCOM_N_TRANSFER] = {
195 [UVSCOM_BULK_DT_WR] = {
197 .endpoint = UE_ADDR_ANY,
198 .direction = UE_DIR_OUT,
199 .bufsize = UVSCOM_BULK_BUF_SIZE,
200 .flags = {.pipe_bof = 1,.force_short_xfer = 1,},
201 .callback = &uvscom_write_callback,
204 [UVSCOM_BULK_DT_RD] = {
206 .endpoint = UE_ADDR_ANY,
207 .direction = UE_DIR_IN,
208 .bufsize = UVSCOM_BULK_BUF_SIZE,
209 .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
210 .callback = &uvscom_read_callback,
213 [UVSCOM_INTR_DT_RD] = {
214 .type = UE_INTERRUPT,
215 .endpoint = UE_ADDR_ANY,
216 .direction = UE_DIR_IN,
217 .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
218 .bufsize = 0, /* use wMaxPacketSize */
219 .callback = &uvscom_intr_callback,
223 static const struct ucom_callback uvscom_callback = {
224 .ucom_cfg_get_status = &uvscom_cfg_get_status,
225 .ucom_cfg_set_dtr = &uvscom_cfg_set_dtr,
226 .ucom_cfg_set_rts = &uvscom_cfg_set_rts,
227 .ucom_cfg_set_break = &uvscom_cfg_set_break,
228 .ucom_cfg_param = &uvscom_cfg_param,
229 .ucom_cfg_open = &uvscom_cfg_open,
230 .ucom_cfg_close = &uvscom_cfg_close,
231 .ucom_pre_open = &uvscom_pre_open,
232 .ucom_pre_param = &uvscom_pre_param,
233 .ucom_start_read = &uvscom_start_read,
234 .ucom_stop_read = &uvscom_stop_read,
235 .ucom_start_write = &uvscom_start_write,
236 .ucom_stop_write = &uvscom_stop_write,
237 .ucom_poll = &uvscom_poll,
238 .ucom_free = &uvscom_free,
241 static const STRUCT_USB_HOST_ID uvscom_devs[] = {
242 /* SUNTAC U-Cable type A4 */
243 {USB_VPI(USB_VENDOR_SUNTAC, USB_PRODUCT_SUNTAC_AS144L4, 0)},
244 /* SUNTAC U-Cable type D2 */
245 {USB_VPI(USB_VENDOR_SUNTAC, USB_PRODUCT_SUNTAC_DS96L, 0)},
246 /* SUNTAC Ir-Trinity */
247 {USB_VPI(USB_VENDOR_SUNTAC, USB_PRODUCT_SUNTAC_IS96U, 0)},
248 /* SUNTAC U-Cable type P1 */
249 {USB_VPI(USB_VENDOR_SUNTAC, USB_PRODUCT_SUNTAC_PS64P1, 0)},
250 /* SUNTAC Slipper U */
251 {USB_VPI(USB_VENDOR_SUNTAC, USB_PRODUCT_SUNTAC_VS10U, 0)},
254 static device_method_t uvscom_methods[] = {
255 DEVMETHOD(device_probe, uvscom_probe),
256 DEVMETHOD(device_attach, uvscom_attach),
257 DEVMETHOD(device_detach, uvscom_detach),
261 static devclass_t uvscom_devclass;
263 static driver_t uvscom_driver = {
265 .methods = uvscom_methods,
266 .size = sizeof(struct uvscom_softc),
269 DRIVER_MODULE(uvscom, uhub, uvscom_driver, uvscom_devclass, NULL, 0);
270 MODULE_DEPEND(uvscom, ucom, 1, 1, 1);
271 MODULE_DEPEND(uvscom, usb, 1, 1, 1);
272 MODULE_VERSION(uvscom, UVSCOM_MODVER);
273 USB_PNP_HOST_INFO(uvscom_devs);
276 uvscom_probe(device_t dev)
278 struct usb_attach_arg *uaa = device_get_ivars(dev);
280 if (uaa->usb_mode != USB_MODE_HOST) {
283 if (uaa->info.bConfigIndex != UVSCOM_CONFIG_INDEX) {
286 if (uaa->info.bIfaceIndex != UVSCOM_IFACE_INDEX) {
289 return (usbd_lookup_id_by_uaa(uvscom_devs, sizeof(uvscom_devs), uaa));
293 uvscom_attach(device_t dev)
295 struct usb_attach_arg *uaa = device_get_ivars(dev);
296 struct uvscom_softc *sc = device_get_softc(dev);
299 device_set_usb_desc(dev);
300 mtx_init(&sc->sc_mtx, "uvscom", NULL, MTX_DEF);
301 ucom_ref(&sc->sc_super_ucom);
303 sc->sc_udev = uaa->device;
305 DPRINTF("sc=%p\n", sc);
307 sc->sc_iface_no = uaa->info.bIfaceNum;
308 sc->sc_iface_index = UVSCOM_IFACE_INDEX;
310 error = usbd_transfer_setup(uaa->device, &sc->sc_iface_index,
311 sc->sc_xfer, uvscom_config, UVSCOM_N_TRANSFER, sc, &sc->sc_mtx);
314 DPRINTF("could not allocate all USB transfers!\n");
317 sc->sc_line = UVSCOM_LINE_INIT;
319 /* clear stall at first run */
320 mtx_lock(&sc->sc_mtx);
321 usbd_xfer_set_stall(sc->sc_xfer[UVSCOM_BULK_DT_WR]);
322 usbd_xfer_set_stall(sc->sc_xfer[UVSCOM_BULK_DT_RD]);
323 mtx_unlock(&sc->sc_mtx);
325 error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
326 &uvscom_callback, &sc->sc_mtx);
330 ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
332 /* start interrupt pipe */
333 mtx_lock(&sc->sc_mtx);
334 usbd_transfer_start(sc->sc_xfer[UVSCOM_INTR_DT_RD]);
335 mtx_unlock(&sc->sc_mtx);
345 uvscom_detach(device_t dev)
347 struct uvscom_softc *sc = device_get_softc(dev);
349 DPRINTF("sc=%p\n", sc);
351 /* stop interrupt pipe */
353 if (sc->sc_xfer[UVSCOM_INTR_DT_RD])
354 usbd_transfer_stop(sc->sc_xfer[UVSCOM_INTR_DT_RD]);
356 ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
357 usbd_transfer_unsetup(sc->sc_xfer, UVSCOM_N_TRANSFER);
359 device_claim_softc(dev);
361 uvscom_free_softc(sc);
366 UCOM_UNLOAD_DRAIN(uvscom);
369 uvscom_free_softc(struct uvscom_softc *sc)
371 if (ucom_unref(&sc->sc_super_ucom)) {
372 mtx_destroy(&sc->sc_mtx);
373 device_free_softc(sc);
378 uvscom_free(struct ucom_softc *ucom)
380 uvscom_free_softc(ucom->sc_parent);
384 uvscom_write_callback(struct usb_xfer *xfer, usb_error_t error)
386 struct uvscom_softc *sc = usbd_xfer_softc(xfer);
387 struct usb_page_cache *pc;
390 switch (USB_GET_STATE(xfer)) {
392 case USB_ST_TRANSFERRED:
394 pc = usbd_xfer_get_frame(xfer, 0);
395 if (ucom_get_data(&sc->sc_ucom, pc, 0,
396 UVSCOM_BULK_BUF_SIZE, &actlen)) {
397 usbd_xfer_set_frame_len(xfer, 0, actlen);
398 usbd_transfer_submit(xfer);
403 if (error != USB_ERR_CANCELLED) {
404 /* try to clear stall first */
405 usbd_xfer_set_stall(xfer);
413 uvscom_read_callback(struct usb_xfer *xfer, usb_error_t error)
415 struct uvscom_softc *sc = usbd_xfer_softc(xfer);
416 struct usb_page_cache *pc;
419 usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
421 switch (USB_GET_STATE(xfer)) {
422 case USB_ST_TRANSFERRED:
423 pc = usbd_xfer_get_frame(xfer, 0);
424 ucom_put_data(&sc->sc_ucom, pc, 0, actlen);
428 usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
429 usbd_transfer_submit(xfer);
433 if (error != USB_ERR_CANCELLED) {
434 /* try to clear stall first */
435 usbd_xfer_set_stall(xfer);
443 uvscom_intr_callback(struct usb_xfer *xfer, usb_error_t error)
445 struct uvscom_softc *sc = usbd_xfer_softc(xfer);
446 struct usb_page_cache *pc;
450 usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
452 switch (USB_GET_STATE(xfer)) {
453 case USB_ST_TRANSFERRED:
455 pc = usbd_xfer_get_frame(xfer, 0);
456 usbd_copy_out(pc, 0, buf, sizeof(buf));
460 sc->sc_unit_status = buf[1];
462 if (buf[0] & UVSCOM_TXRDY) {
463 sc->sc_lsr |= ULSR_TXRDY;
465 if (buf[0] & UVSCOM_RXRDY) {
466 sc->sc_lsr |= ULSR_RXRDY;
468 if (buf[1] & UVSCOM_CTS) {
469 sc->sc_msr |= SER_CTS;
471 if (buf[1] & UVSCOM_DSR) {
472 sc->sc_msr |= SER_DSR;
474 if (buf[1] & UVSCOM_DCD) {
475 sc->sc_msr |= SER_DCD;
478 * the UCOM layer will ignore this call if the TTY
481 ucom_status_change(&sc->sc_ucom);
485 usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
486 usbd_transfer_submit(xfer);
490 if (error != USB_ERR_CANCELLED) {
491 /* try to clear stall first */
492 usbd_xfer_set_stall(xfer);
500 uvscom_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
502 struct uvscom_softc *sc = ucom->sc_parent;
504 DPRINTF("onoff = %d\n", onoff);
507 sc->sc_line |= UVSCOM_DTR;
509 sc->sc_line &= ~UVSCOM_DTR;
511 uvscom_cfg_write(sc, UVSCOM_LINE_CTL, sc->sc_line);
515 uvscom_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
517 struct uvscom_softc *sc = ucom->sc_parent;
519 DPRINTF("onoff = %d\n", onoff);
522 sc->sc_line |= UVSCOM_RTS;
524 sc->sc_line &= ~UVSCOM_RTS;
526 uvscom_cfg_write(sc, UVSCOM_LINE_CTL, sc->sc_line);
530 uvscom_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
532 struct uvscom_softc *sc = ucom->sc_parent;
534 DPRINTF("onoff = %d\n", onoff);
537 sc->sc_line |= UVSCOM_BREAK;
539 sc->sc_line &= ~UVSCOM_BREAK;
541 uvscom_cfg_write(sc, UVSCOM_LINE_CTL, sc->sc_line);
545 uvscom_pre_param(struct ucom_softc *ucom, struct termios *t)
547 switch (t->c_ospeed) {
566 uvscom_cfg_param(struct ucom_softc *ucom, struct termios *t)
568 struct uvscom_softc *sc = ucom->sc_parent;
573 switch (t->c_ospeed) {
575 value = UVSCOM_SPEED_150BPS;
578 value = UVSCOM_SPEED_300BPS;
581 value = UVSCOM_SPEED_600BPS;
584 value = UVSCOM_SPEED_1200BPS;
587 value = UVSCOM_SPEED_2400BPS;
590 value = UVSCOM_SPEED_4800BPS;
593 value = UVSCOM_SPEED_9600BPS;
596 value = UVSCOM_SPEED_19200BPS;
599 value = UVSCOM_SPEED_38400BPS;
602 value = UVSCOM_SPEED_57600BPS;
605 value = UVSCOM_SPEED_115200BPS;
611 uvscom_cfg_write(sc, UVSCOM_SET_SPEED, value);
615 if (t->c_cflag & CSTOPB) {
616 value |= UVSCOM_STOP_BIT_2;
618 if (t->c_cflag & PARENB) {
619 if (t->c_cflag & PARODD) {
620 value |= UVSCOM_PARITY_ODD;
622 value |= UVSCOM_PARITY_EVEN;
625 value |= UVSCOM_PARITY_NONE;
628 switch (t->c_cflag & CSIZE) {
630 value |= UVSCOM_DATA_BIT_5;
633 value |= UVSCOM_DATA_BIT_6;
636 value |= UVSCOM_DATA_BIT_7;
640 value |= UVSCOM_DATA_BIT_8;
644 uvscom_cfg_write(sc, UVSCOM_SET_PARAM, value);
648 uvscom_pre_open(struct ucom_softc *ucom)
650 struct uvscom_softc *sc = ucom->sc_parent;
652 DPRINTF("sc = %p\n", sc);
654 /* check if PC card was inserted */
656 if (sc->sc_unit_status & UVSCOM_NOCARD) {
657 DPRINTF("no PC card!\n");
664 uvscom_cfg_open(struct ucom_softc *ucom)
666 struct uvscom_softc *sc = ucom->sc_parent;
668 DPRINTF("sc = %p\n", sc);
670 uvscom_cfg_read_status(sc);
674 uvscom_cfg_close(struct ucom_softc *ucom)
676 struct uvscom_softc *sc = ucom->sc_parent;
678 DPRINTF("sc=%p\n", sc);
680 uvscom_cfg_write(sc, UVSCOM_SHUTDOWN, 0);
684 uvscom_start_read(struct ucom_softc *ucom)
686 struct uvscom_softc *sc = ucom->sc_parent;
688 usbd_transfer_start(sc->sc_xfer[UVSCOM_BULK_DT_RD]);
692 uvscom_stop_read(struct ucom_softc *ucom)
694 struct uvscom_softc *sc = ucom->sc_parent;
696 usbd_transfer_stop(sc->sc_xfer[UVSCOM_BULK_DT_RD]);
700 uvscom_start_write(struct ucom_softc *ucom)
702 struct uvscom_softc *sc = ucom->sc_parent;
704 usbd_transfer_start(sc->sc_xfer[UVSCOM_BULK_DT_WR]);
708 uvscom_stop_write(struct ucom_softc *ucom)
710 struct uvscom_softc *sc = ucom->sc_parent;
712 usbd_transfer_stop(sc->sc_xfer[UVSCOM_BULK_DT_WR]);
716 uvscom_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
718 struct uvscom_softc *sc = ucom->sc_parent;
725 uvscom_cfg_write(struct uvscom_softc *sc, uint8_t index, uint16_t value)
727 struct usb_device_request req;
730 req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
731 req.bRequest = index;
732 USETW(req.wValue, value);
733 USETW(req.wIndex, 0);
734 USETW(req.wLength, 0);
736 err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom,
737 &req, NULL, 0, 1000);
739 DPRINTFN(0, "device request failed, err=%s "
740 "(ignored)\n", usbd_errstr(err));
745 uvscom_cfg_read_status(struct uvscom_softc *sc)
747 struct usb_device_request req;
751 req.bmRequestType = UT_READ_VENDOR_DEVICE;
752 req.bRequest = UVSCOM_READ_STATUS;
753 USETW(req.wValue, 0);
754 USETW(req.wIndex, 0);
755 USETW(req.wLength, 2);
757 err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom,
758 &req, data, 0, 1000);
760 DPRINTFN(0, "device request failed, err=%s "
761 "(ignored)\n", usbd_errstr(err));
763 return (data[0] | (data[1] << 8));
767 uvscom_poll(struct ucom_softc *ucom)
769 struct uvscom_softc *sc = ucom->sc_parent;
770 usbd_transfer_poll(sc->sc_xfer, UVSCOM_N_TRANSFER);