xref: /freebsd/sys/dev/usb/serial/umct.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 #include <sys/cdefs.h>
2 __FBSDID("$FreeBSD$");
3 
4 /*-
5  * Copyright (c) 2003 Scott Long
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  */
30 
31 /*
32  * Driver for the MCT (Magic Control Technology) USB-RS232 Converter.
33  * Based on the superb documentation from the linux mct_u232 driver by
34  * Wolfgang Grandeggar <wolfgang@cec.ch>.
35  * This device smells a lot like the Belkin F5U103, except that it has
36  * suffered some mild brain-damage.  This driver is based off of the ubsa.c
37  * driver from Alexander Kabaev <kan@FreeBSD.org>.  Merging the two together
38  * might be useful, though the subtle differences might lead to lots of
39  * #ifdef's.
40  */
41 
42 /*
43  * NOTE: all function names beginning like "umct_cfg_" can only
44  * be called from within the config thread function !
45  */
46 
47 #include <sys/stdint.h>
48 #include <sys/stddef.h>
49 #include <sys/param.h>
50 #include <sys/queue.h>
51 #include <sys/types.h>
52 #include <sys/systm.h>
53 #include <sys/kernel.h>
54 #include <sys/bus.h>
55 #include <sys/module.h>
56 #include <sys/lock.h>
57 #include <sys/mutex.h>
58 #include <sys/condvar.h>
59 #include <sys/sysctl.h>
60 #include <sys/sx.h>
61 #include <sys/unistd.h>
62 #include <sys/callout.h>
63 #include <sys/malloc.h>
64 #include <sys/priv.h>
65 
66 #include <dev/usb/usb.h>
67 #include <dev/usb/usbdi.h>
68 #include <dev/usb/usbdi_util.h>
69 #include "usbdevs.h"
70 
71 #define	USB_DEBUG_VAR usb_debug
72 #include <dev/usb/usb_debug.h>
73 #include <dev/usb/usb_process.h>
74 
75 #include <dev/usb/serial/usb_serial.h>
76 
77 /* The UMCT advertises the standard 8250 UART registers */
78 #define	UMCT_GET_MSR		2	/* Get Modem Status Register */
79 #define	UMCT_GET_MSR_SIZE	1
80 #define	UMCT_GET_LCR		6	/* Get Line Control Register */
81 #define	UMCT_GET_LCR_SIZE	1
82 #define	UMCT_SET_BAUD		5	/* Set the Baud Rate Divisor */
83 #define	UMCT_SET_BAUD_SIZE	4
84 #define	UMCT_SET_LCR		7	/* Set Line Control Register */
85 #define	UMCT_SET_LCR_SIZE	1
86 #define	UMCT_SET_MCR		10	/* Set Modem Control Register */
87 #define	UMCT_SET_MCR_SIZE	1
88 
89 #define	UMCT_INTR_INTERVAL	100
90 #define	UMCT_IFACE_INDEX	0
91 #define	UMCT_CONFIG_INDEX	0
92 
93 enum {
94 	UMCT_BULK_DT_WR,
95 	UMCT_BULK_DT_RD,
96 	UMCT_INTR_DT_RD,
97 	UMCT_N_TRANSFER,
98 };
99 
100 struct umct_softc {
101 	struct ucom_super_softc sc_super_ucom;
102 	struct ucom_softc sc_ucom;
103 
104 	struct usb_device *sc_udev;
105 	struct usb_xfer *sc_xfer[UMCT_N_TRANSFER];
106 	struct mtx sc_mtx;
107 
108 	uint32_t sc_unit;
109 
110 	uint16_t sc_obufsize;
111 
112 	uint8_t	sc_lsr;
113 	uint8_t	sc_msr;
114 	uint8_t	sc_lcr;
115 	uint8_t	sc_mcr;
116 	uint8_t	sc_iface_no;
117 	uint8_t sc_swap_cb;
118 };
119 
120 /* prototypes */
121 
122 static device_probe_t umct_probe;
123 static device_attach_t umct_attach;
124 static device_detach_t umct_detach;
125 static void umct_free_softc(struct umct_softc *);
126 
127 static usb_callback_t umct_intr_callback;
128 static usb_callback_t umct_intr_callback_sub;
129 static usb_callback_t umct_read_callback;
130 static usb_callback_t umct_read_callback_sub;
131 static usb_callback_t umct_write_callback;
132 
133 static void	umct_cfg_do_request(struct umct_softc *sc, uint8_t request,
134 		    uint16_t len, uint32_t value);
135 static void	umct_free(struct ucom_softc *);
136 static void	umct_cfg_get_status(struct ucom_softc *, uint8_t *,
137 		    uint8_t *);
138 static void	umct_cfg_set_break(struct ucom_softc *, uint8_t);
139 static void	umct_cfg_set_dtr(struct ucom_softc *, uint8_t);
140 static void	umct_cfg_set_rts(struct ucom_softc *, uint8_t);
141 static uint8_t	umct_calc_baud(uint32_t);
142 static int	umct_pre_param(struct ucom_softc *, struct termios *);
143 static void	umct_cfg_param(struct ucom_softc *, struct termios *);
144 static void	umct_start_read(struct ucom_softc *);
145 static void	umct_stop_read(struct ucom_softc *);
146 static void	umct_start_write(struct ucom_softc *);
147 static void	umct_stop_write(struct ucom_softc *);
148 static void	umct_poll(struct ucom_softc *ucom);
149 
150 static const struct usb_config umct_config[UMCT_N_TRANSFER] = {
151 
152 	[UMCT_BULK_DT_WR] = {
153 		.type = UE_BULK,
154 		.endpoint = UE_ADDR_ANY,
155 		.direction = UE_DIR_OUT,
156 		.bufsize = 0,	/* use wMaxPacketSize */
157 		.flags = {.pipe_bof = 1,.force_short_xfer = 1,},
158 		.callback = &umct_write_callback,
159 	},
160 
161 	[UMCT_BULK_DT_RD] = {
162 		.type = UE_INTERRUPT,
163 		.endpoint = UE_ADDR_ANY,
164 		.direction = UE_DIR_IN,
165 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
166 		.bufsize = 0,	/* use wMaxPacketSize */
167 		.callback = &umct_read_callback,
168 		.ep_index = 0,		/* first interrupt endpoint */
169 	},
170 
171 	[UMCT_INTR_DT_RD] = {
172 		.type = UE_INTERRUPT,
173 		.endpoint = UE_ADDR_ANY,
174 		.direction = UE_DIR_IN,
175 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
176 		.bufsize = 0,	/* use wMaxPacketSize */
177 		.callback = &umct_intr_callback,
178 		.ep_index = 1,		/* second interrupt endpoint */
179 	},
180 };
181 
182 static const struct ucom_callback umct_callback = {
183 	.ucom_cfg_get_status = &umct_cfg_get_status,
184 	.ucom_cfg_set_dtr = &umct_cfg_set_dtr,
185 	.ucom_cfg_set_rts = &umct_cfg_set_rts,
186 	.ucom_cfg_set_break = &umct_cfg_set_break,
187 	.ucom_cfg_param = &umct_cfg_param,
188 	.ucom_pre_param = &umct_pre_param,
189 	.ucom_start_read = &umct_start_read,
190 	.ucom_stop_read = &umct_stop_read,
191 	.ucom_start_write = &umct_start_write,
192 	.ucom_stop_write = &umct_stop_write,
193 	.ucom_poll = &umct_poll,
194 	.ucom_free = &umct_free,
195 };
196 
197 static const STRUCT_USB_HOST_ID umct_devs[] = {
198 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_USB232, 0)},
199 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_SITECOM_USB232, 0)},
200 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_DU_H3SP_USB232, 0)},
201 	{USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U109, 0)},
202 	{USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U409, 0)},
203 };
204 
205 static device_method_t umct_methods[] = {
206 	DEVMETHOD(device_probe, umct_probe),
207 	DEVMETHOD(device_attach, umct_attach),
208 	DEVMETHOD(device_detach, umct_detach),
209 	DEVMETHOD_END
210 };
211 
212 static devclass_t umct_devclass;
213 
214 static driver_t umct_driver = {
215 	.name = "umct",
216 	.methods = umct_methods,
217 	.size = sizeof(struct umct_softc),
218 };
219 
220 DRIVER_MODULE(umct, uhub, umct_driver, umct_devclass, NULL, 0);
221 MODULE_DEPEND(umct, ucom, 1, 1, 1);
222 MODULE_DEPEND(umct, usb, 1, 1, 1);
223 MODULE_VERSION(umct, 1);
224 
225 static int
226 umct_probe(device_t dev)
227 {
228 	struct usb_attach_arg *uaa = device_get_ivars(dev);
229 
230 	if (uaa->usb_mode != USB_MODE_HOST) {
231 		return (ENXIO);
232 	}
233 	if (uaa->info.bConfigIndex != UMCT_CONFIG_INDEX) {
234 		return (ENXIO);
235 	}
236 	if (uaa->info.bIfaceIndex != UMCT_IFACE_INDEX) {
237 		return (ENXIO);
238 	}
239 	return (usbd_lookup_id_by_uaa(umct_devs, sizeof(umct_devs), uaa));
240 }
241 
242 static int
243 umct_attach(device_t dev)
244 {
245 	struct usb_attach_arg *uaa = device_get_ivars(dev);
246 	struct umct_softc *sc = device_get_softc(dev);
247 	int32_t error;
248 	uint16_t maxp;
249 	uint8_t iface_index;
250 
251 	sc->sc_udev = uaa->device;
252 	sc->sc_unit = device_get_unit(dev);
253 
254 	device_set_usb_desc(dev);
255 	mtx_init(&sc->sc_mtx, "umct", NULL, MTX_DEF);
256 	ucom_ref(&sc->sc_super_ucom);
257 
258 	sc->sc_iface_no = uaa->info.bIfaceNum;
259 
260 	iface_index = UMCT_IFACE_INDEX;
261 	error = usbd_transfer_setup(uaa->device, &iface_index,
262 	    sc->sc_xfer, umct_config, UMCT_N_TRANSFER, sc, &sc->sc_mtx);
263 
264 	if (error) {
265 		device_printf(dev, "allocating USB "
266 		    "transfers failed\n");
267 		goto detach;
268 	}
269 
270 	/*
271 	 * The real bulk-in endpoint is also marked as an interrupt.
272 	 * The only way to differentiate it from the real interrupt
273 	 * endpoint is to look at the wMaxPacketSize field.
274 	 */
275 	maxp = usbd_xfer_max_framelen(sc->sc_xfer[UMCT_BULK_DT_RD]);
276 	if (maxp == 0x2) {
277 
278 		/* guessed wrong - switch around endpoints */
279 
280 		struct usb_xfer *temp = sc->sc_xfer[UMCT_INTR_DT_RD];
281 
282 		sc->sc_xfer[UMCT_INTR_DT_RD] = sc->sc_xfer[UMCT_BULK_DT_RD];
283 		sc->sc_xfer[UMCT_BULK_DT_RD] = temp;
284 		sc->sc_swap_cb = 1;
285 	}
286 
287 	sc->sc_obufsize = usbd_xfer_max_len(sc->sc_xfer[UMCT_BULK_DT_WR]);
288 
289 	if (uaa->info.idProduct == USB_PRODUCT_MCT_SITECOM_USB232) {
290 		if (sc->sc_obufsize > 16) {
291 			sc->sc_obufsize = 16;
292 		}
293 	}
294 	error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
295 	    &umct_callback, &sc->sc_mtx);
296 	if (error) {
297 		goto detach;
298 	}
299 	ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
300 
301 	return (0);			/* success */
302 
303 detach:
304 	umct_detach(dev);
305 	return (ENXIO);			/* failure */
306 }
307 
308 static int
309 umct_detach(device_t dev)
310 {
311 	struct umct_softc *sc = device_get_softc(dev);
312 
313 	ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
314 	usbd_transfer_unsetup(sc->sc_xfer, UMCT_N_TRANSFER);
315 
316 	device_claim_softc(dev);
317 
318 	umct_free_softc(sc);
319 
320 	return (0);
321 }
322 
323 UCOM_UNLOAD_DRAIN(umct);
324 
325 static void
326 umct_free_softc(struct umct_softc *sc)
327 {
328 	if (ucom_unref(&sc->sc_super_ucom)) {
329 		mtx_destroy(&sc->sc_mtx);
330 		device_free_softc(sc);
331 	}
332 }
333 
334 static void
335 umct_free(struct ucom_softc *ucom)
336 {
337 	umct_free_softc(ucom->sc_parent);
338 }
339 
340 static void
341 umct_cfg_do_request(struct umct_softc *sc, uint8_t request,
342     uint16_t len, uint32_t value)
343 {
344 	struct usb_device_request req;
345 	usb_error_t err;
346 	uint8_t temp[4];
347 
348 	if (len > 4)
349 		len = 4;
350 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
351 	req.bRequest = request;
352 	USETW(req.wValue, 0);
353 	req.wIndex[0] = sc->sc_iface_no;
354 	req.wIndex[1] = 0;
355 	USETW(req.wLength, len);
356 	USETDW(temp, value);
357 
358 	err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom,
359 	    &req, temp, 0, 1000);
360 	if (err) {
361 		DPRINTFN(0, "device request failed, err=%s "
362 		    "(ignored)\n", usbd_errstr(err));
363 	}
364 	return;
365 }
366 
367 static void
368 umct_intr_callback_sub(struct usb_xfer *xfer, usb_error_t error)
369 {
370 	struct umct_softc *sc = usbd_xfer_softc(xfer);
371 	struct usb_page_cache *pc;
372 	uint8_t buf[2];
373 	int actlen;
374 
375 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
376 
377 	switch (USB_GET_STATE(xfer)) {
378 	case USB_ST_TRANSFERRED:
379 		if (actlen < 2) {
380 			DPRINTF("too short message\n");
381 			goto tr_setup;
382 		}
383 		pc = usbd_xfer_get_frame(xfer, 0);
384 		usbd_copy_out(pc, 0, buf, sizeof(buf));
385 
386 		sc->sc_msr = buf[0];
387 		sc->sc_lsr = buf[1];
388 
389 		ucom_status_change(&sc->sc_ucom);
390 
391 	case USB_ST_SETUP:
392 tr_setup:
393 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
394 		usbd_transfer_submit(xfer);
395 		return;
396 
397 	default:			/* Error */
398 		if (error != USB_ERR_CANCELLED) {
399 			/* try to clear stall first */
400 			usbd_xfer_set_stall(xfer);
401 			goto tr_setup;
402 		}
403 		return;
404 	}
405 }
406 
407 static void
408 umct_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
409 {
410 	struct umct_softc *sc = ucom->sc_parent;
411 
412 	*lsr = sc->sc_lsr;
413 	*msr = sc->sc_msr;
414 }
415 
416 static void
417 umct_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
418 {
419 	struct umct_softc *sc = ucom->sc_parent;
420 
421 	if (onoff)
422 		sc->sc_lcr |= 0x40;
423 	else
424 		sc->sc_lcr &= ~0x40;
425 
426 	umct_cfg_do_request(sc, UMCT_SET_LCR, UMCT_SET_LCR_SIZE, sc->sc_lcr);
427 }
428 
429 static void
430 umct_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
431 {
432 	struct umct_softc *sc = ucom->sc_parent;
433 
434 	if (onoff)
435 		sc->sc_mcr |= 0x01;
436 	else
437 		sc->sc_mcr &= ~0x01;
438 
439 	umct_cfg_do_request(sc, UMCT_SET_MCR, UMCT_SET_MCR_SIZE, sc->sc_mcr);
440 }
441 
442 static void
443 umct_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
444 {
445 	struct umct_softc *sc = ucom->sc_parent;
446 
447 	if (onoff)
448 		sc->sc_mcr |= 0x02;
449 	else
450 		sc->sc_mcr &= ~0x02;
451 
452 	umct_cfg_do_request(sc, UMCT_SET_MCR, UMCT_SET_MCR_SIZE, sc->sc_mcr);
453 }
454 
455 static uint8_t
456 umct_calc_baud(uint32_t baud)
457 {
458 	switch (baud) {
459 		case B300:return (0x1);
460 	case B600:
461 		return (0x2);
462 	case B1200:
463 		return (0x3);
464 	case B2400:
465 		return (0x4);
466 	case B4800:
467 		return (0x6);
468 	case B9600:
469 		return (0x8);
470 	case B19200:
471 		return (0x9);
472 	case B38400:
473 		return (0xa);
474 	case B57600:
475 		return (0xb);
476 	case 115200:
477 		return (0xc);
478 	case B0:
479 	default:
480 		break;
481 	}
482 	return (0x0);
483 }
484 
485 static int
486 umct_pre_param(struct ucom_softc *ucom, struct termios *t)
487 {
488 	return (0);			/* we accept anything */
489 }
490 
491 static void
492 umct_cfg_param(struct ucom_softc *ucom, struct termios *t)
493 {
494 	struct umct_softc *sc = ucom->sc_parent;
495 	uint32_t value;
496 
497 	value = umct_calc_baud(t->c_ospeed);
498 	umct_cfg_do_request(sc, UMCT_SET_BAUD, UMCT_SET_BAUD_SIZE, value);
499 
500 	value = (sc->sc_lcr & 0x40);
501 
502 	switch (t->c_cflag & CSIZE) {
503 	case CS5:
504 		value |= 0x0;
505 		break;
506 	case CS6:
507 		value |= 0x1;
508 		break;
509 	case CS7:
510 		value |= 0x2;
511 		break;
512 	default:
513 	case CS8:
514 		value |= 0x3;
515 		break;
516 	}
517 
518 	value |= (t->c_cflag & CSTOPB) ? 0x4 : 0;
519 	if (t->c_cflag & PARENB) {
520 		value |= 0x8;
521 		value |= (t->c_cflag & PARODD) ? 0x0 : 0x10;
522 	}
523 	/*
524 	 * XXX There doesn't seem to be a way to tell the device
525 	 * to use flow control.
526 	 */
527 
528 	sc->sc_lcr = value;
529 	umct_cfg_do_request(sc, UMCT_SET_LCR, UMCT_SET_LCR_SIZE, value);
530 }
531 
532 static void
533 umct_start_read(struct ucom_softc *ucom)
534 {
535 	struct umct_softc *sc = ucom->sc_parent;
536 
537 	/* start interrupt endpoint */
538 	usbd_transfer_start(sc->sc_xfer[UMCT_INTR_DT_RD]);
539 
540 	/* start read endpoint */
541 	usbd_transfer_start(sc->sc_xfer[UMCT_BULK_DT_RD]);
542 }
543 
544 static void
545 umct_stop_read(struct ucom_softc *ucom)
546 {
547 	struct umct_softc *sc = ucom->sc_parent;
548 
549 	/* stop interrupt endpoint */
550 	usbd_transfer_stop(sc->sc_xfer[UMCT_INTR_DT_RD]);
551 
552 	/* stop read endpoint */
553 	usbd_transfer_stop(sc->sc_xfer[UMCT_BULK_DT_RD]);
554 }
555 
556 static void
557 umct_start_write(struct ucom_softc *ucom)
558 {
559 	struct umct_softc *sc = ucom->sc_parent;
560 
561 	usbd_transfer_start(sc->sc_xfer[UMCT_BULK_DT_WR]);
562 }
563 
564 static void
565 umct_stop_write(struct ucom_softc *ucom)
566 {
567 	struct umct_softc *sc = ucom->sc_parent;
568 
569 	usbd_transfer_stop(sc->sc_xfer[UMCT_BULK_DT_WR]);
570 }
571 
572 static void
573 umct_read_callback(struct usb_xfer *xfer, usb_error_t error)
574 {
575 	struct umct_softc *sc = usbd_xfer_softc(xfer);
576 
577 	if (sc->sc_swap_cb)
578 		umct_intr_callback_sub(xfer, error);
579 	else
580 		umct_read_callback_sub(xfer, error);
581 }
582 
583 static void
584 umct_intr_callback(struct usb_xfer *xfer, usb_error_t error)
585 {
586 	struct umct_softc *sc = usbd_xfer_softc(xfer);
587 
588 	if (sc->sc_swap_cb)
589 		umct_read_callback_sub(xfer, error);
590 	else
591 		umct_intr_callback_sub(xfer, error);
592 }
593 
594 static void
595 umct_write_callback(struct usb_xfer *xfer, usb_error_t error)
596 {
597 	struct umct_softc *sc = usbd_xfer_softc(xfer);
598 	struct usb_page_cache *pc;
599 	uint32_t actlen;
600 
601 	switch (USB_GET_STATE(xfer)) {
602 	case USB_ST_SETUP:
603 	case USB_ST_TRANSFERRED:
604 tr_setup:
605 		pc = usbd_xfer_get_frame(xfer, 0);
606 		if (ucom_get_data(&sc->sc_ucom, pc, 0,
607 		    sc->sc_obufsize, &actlen)) {
608 
609 			usbd_xfer_set_frame_len(xfer, 0, actlen);
610 			usbd_transfer_submit(xfer);
611 		}
612 		return;
613 
614 	default:			/* Error */
615 		if (error != USB_ERR_CANCELLED) {
616 			/* try to clear stall first */
617 			usbd_xfer_set_stall(xfer);
618 			goto tr_setup;
619 		}
620 		return;
621 	}
622 }
623 
624 static void
625 umct_read_callback_sub(struct usb_xfer *xfer, usb_error_t error)
626 {
627 	struct umct_softc *sc = usbd_xfer_softc(xfer);
628 	struct usb_page_cache *pc;
629 	int actlen;
630 
631 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
632 
633 	switch (USB_GET_STATE(xfer)) {
634 	case USB_ST_TRANSFERRED:
635 		pc = usbd_xfer_get_frame(xfer, 0);
636 		ucom_put_data(&sc->sc_ucom, pc, 0, actlen);
637 
638 	case USB_ST_SETUP:
639 tr_setup:
640 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
641 		usbd_transfer_submit(xfer);
642 		return;
643 
644 	default:			/* Error */
645 		if (error != USB_ERR_CANCELLED) {
646 			/* try to clear stall first */
647 			usbd_xfer_set_stall(xfer);
648 			goto tr_setup;
649 		}
650 		return;
651 	}
652 }
653 
654 static void
655 umct_poll(struct ucom_softc *ucom)
656 {
657 	struct umct_softc *sc = ucom->sc_parent;
658 	usbd_transfer_poll(sc->sc_xfer, UMCT_N_TRANSFER);
659 }
660