xref: /freebsd/sys/dev/usb/serial/umct.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 #include <sys/cdefs.h>
2 __FBSDID("$FreeBSD$");
3 
4 /*-
5  * SPDX-License-Identifier: BSD-2-Clause
6  *
7  * Copyright (c) 2003 Scott Long
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  */
32 
33 /*
34  * Driver for the MCT (Magic Control Technology) USB-RS232 Converter.
35  * Based on the superb documentation from the linux mct_u232 driver by
36  * Wolfgang Grandeggar <wolfgang@cec.ch>.
37  * This device smells a lot like the Belkin F5U103, except that it has
38  * suffered some mild brain-damage.  This driver is based off of the ubsa.c
39  * driver from Alexander Kabaev <kan@FreeBSD.org>.  Merging the two together
40  * might be useful, though the subtle differences might lead to lots of
41  * #ifdef's.
42  */
43 
44 /*
45  * NOTE: all function names beginning like "umct_cfg_" can only
46  * be called from within the config thread function !
47  */
48 
49 #include <sys/stdint.h>
50 #include <sys/stddef.h>
51 #include <sys/param.h>
52 #include <sys/queue.h>
53 #include <sys/types.h>
54 #include <sys/systm.h>
55 #include <sys/kernel.h>
56 #include <sys/bus.h>
57 #include <sys/module.h>
58 #include <sys/lock.h>
59 #include <sys/mutex.h>
60 #include <sys/condvar.h>
61 #include <sys/sysctl.h>
62 #include <sys/sx.h>
63 #include <sys/unistd.h>
64 #include <sys/callout.h>
65 #include <sys/malloc.h>
66 #include <sys/priv.h>
67 
68 #include <dev/usb/usb.h>
69 #include <dev/usb/usbdi.h>
70 #include <dev/usb/usbdi_util.h>
71 #include "usbdevs.h"
72 
73 #define	USB_DEBUG_VAR usb_debug
74 #include <dev/usb/usb_debug.h>
75 #include <dev/usb/usb_process.h>
76 
77 #include <dev/usb/serial/usb_serial.h>
78 
79 /* The UMCT advertises the standard 8250 UART registers */
80 #define	UMCT_GET_MSR		2	/* Get Modem Status Register */
81 #define	UMCT_GET_MSR_SIZE	1
82 #define	UMCT_GET_LCR		6	/* Get Line Control Register */
83 #define	UMCT_GET_LCR_SIZE	1
84 #define	UMCT_SET_BAUD		5	/* Set the Baud Rate Divisor */
85 #define	UMCT_SET_BAUD_SIZE	4
86 #define	UMCT_SET_LCR		7	/* Set Line Control Register */
87 #define	UMCT_SET_LCR_SIZE	1
88 #define	UMCT_SET_MCR		10	/* Set Modem Control Register */
89 #define	UMCT_SET_MCR_SIZE	1
90 
91 #define	UMCT_MSR_CTS_CHG	0x01
92 #define	UMCT_MSR_DSR_CHG	0x02
93 #define	UMCT_MSR_RI_CHG		0x04
94 #define	UMCT_MSR_CD_CHG		0x08
95 #define	UMCT_MSR_CTS		0x10
96 #define	UMCT_MSR_RTS		0x20
97 #define	UMCT_MSR_RI		0x40
98 #define	UMCT_MSR_CD		0x80
99 
100 #define	UMCT_INTR_INTERVAL	100
101 #define	UMCT_IFACE_INDEX	0
102 #define	UMCT_CONFIG_INDEX	0
103 
104 enum {
105 	UMCT_BULK_DT_WR,
106 	UMCT_BULK_DT_RD,
107 	UMCT_INTR_DT_RD,
108 	UMCT_N_TRANSFER,
109 };
110 
111 struct umct_softc {
112 	struct ucom_super_softc sc_super_ucom;
113 	struct ucom_softc sc_ucom;
114 
115 	struct usb_device *sc_udev;
116 	struct usb_xfer *sc_xfer[UMCT_N_TRANSFER];
117 	struct mtx sc_mtx;
118 
119 	uint32_t sc_unit;
120 
121 	uint16_t sc_obufsize;
122 
123 	uint8_t	sc_lsr;
124 	uint8_t	sc_msr;
125 	uint8_t	sc_lcr;
126 	uint8_t	sc_mcr;
127 	uint8_t	sc_iface_no;
128 	uint8_t sc_swap_cb;
129 };
130 
131 /* prototypes */
132 
133 static device_probe_t umct_probe;
134 static device_attach_t umct_attach;
135 static device_detach_t umct_detach;
136 static void umct_free_softc(struct umct_softc *);
137 
138 static usb_callback_t umct_intr_callback;
139 static usb_callback_t umct_intr_callback_sub;
140 static usb_callback_t umct_read_callback;
141 static usb_callback_t umct_read_callback_sub;
142 static usb_callback_t umct_write_callback;
143 
144 static void	umct_cfg_do_request(struct umct_softc *sc, uint8_t request,
145 		    uint16_t len, uint32_t value);
146 static void	umct_free(struct ucom_softc *);
147 static void	umct_cfg_get_status(struct ucom_softc *, uint8_t *,
148 		    uint8_t *);
149 static void	umct_cfg_set_break(struct ucom_softc *, uint8_t);
150 static void	umct_cfg_set_dtr(struct ucom_softc *, uint8_t);
151 static void	umct_cfg_set_rts(struct ucom_softc *, uint8_t);
152 static uint8_t	umct_calc_baud(uint32_t);
153 static int	umct_pre_param(struct ucom_softc *, struct termios *);
154 static void	umct_cfg_param(struct ucom_softc *, struct termios *);
155 static void	umct_start_read(struct ucom_softc *);
156 static void	umct_stop_read(struct ucom_softc *);
157 static void	umct_start_write(struct ucom_softc *);
158 static void	umct_stop_write(struct ucom_softc *);
159 static void	umct_poll(struct ucom_softc *ucom);
160 
161 static const struct usb_config umct_config[UMCT_N_TRANSFER] = {
162 	[UMCT_BULK_DT_WR] = {
163 		.type = UE_BULK,
164 		.endpoint = UE_ADDR_ANY,
165 		.direction = UE_DIR_OUT,
166 		.bufsize = 0,	/* use wMaxPacketSize */
167 		.flags = {.pipe_bof = 1,.force_short_xfer = 1,},
168 		.callback = &umct_write_callback,
169 	},
170 
171 	[UMCT_BULK_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_read_callback,
178 		.ep_index = 0,		/* first interrupt endpoint */
179 	},
180 
181 	[UMCT_INTR_DT_RD] = {
182 		.type = UE_INTERRUPT,
183 		.endpoint = UE_ADDR_ANY,
184 		.direction = UE_DIR_IN,
185 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
186 		.bufsize = 0,	/* use wMaxPacketSize */
187 		.callback = &umct_intr_callback,
188 		.ep_index = 1,		/* second interrupt endpoint */
189 	},
190 };
191 
192 static const struct ucom_callback umct_callback = {
193 	.ucom_cfg_get_status = &umct_cfg_get_status,
194 	.ucom_cfg_set_dtr = &umct_cfg_set_dtr,
195 	.ucom_cfg_set_rts = &umct_cfg_set_rts,
196 	.ucom_cfg_set_break = &umct_cfg_set_break,
197 	.ucom_cfg_param = &umct_cfg_param,
198 	.ucom_pre_param = &umct_pre_param,
199 	.ucom_start_read = &umct_start_read,
200 	.ucom_stop_read = &umct_stop_read,
201 	.ucom_start_write = &umct_start_write,
202 	.ucom_stop_write = &umct_stop_write,
203 	.ucom_poll = &umct_poll,
204 	.ucom_free = &umct_free,
205 };
206 
207 static const STRUCT_USB_HOST_ID umct_devs[] = {
208 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_USB232, 0)},
209 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_SITECOM_USB232, 0)},
210 	{USB_VPI(USB_VENDOR_MCT, USB_PRODUCT_MCT_DU_H3SP_USB232, 0)},
211 	{USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U109, 0)},
212 	{USB_VPI(USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U409, 0)},
213 };
214 
215 static device_method_t umct_methods[] = {
216 	DEVMETHOD(device_probe, umct_probe),
217 	DEVMETHOD(device_attach, umct_attach),
218 	DEVMETHOD(device_detach, umct_detach),
219 	DEVMETHOD_END
220 };
221 
222 static driver_t umct_driver = {
223 	.name = "umct",
224 	.methods = umct_methods,
225 	.size = sizeof(struct umct_softc),
226 };
227 
228 DRIVER_MODULE(umct, uhub, umct_driver, NULL, NULL);
229 MODULE_DEPEND(umct, ucom, 1, 1, 1);
230 MODULE_DEPEND(umct, usb, 1, 1, 1);
231 MODULE_VERSION(umct, 1);
232 USB_PNP_HOST_INFO(umct_devs);
233 
234 static int
235 umct_probe(device_t dev)
236 {
237 	struct usb_attach_arg *uaa = device_get_ivars(dev);
238 
239 	if (uaa->usb_mode != USB_MODE_HOST) {
240 		return (ENXIO);
241 	}
242 	if (uaa->info.bConfigIndex != UMCT_CONFIG_INDEX) {
243 		return (ENXIO);
244 	}
245 	if (uaa->info.bIfaceIndex != UMCT_IFACE_INDEX) {
246 		return (ENXIO);
247 	}
248 	return (usbd_lookup_id_by_uaa(umct_devs, sizeof(umct_devs), uaa));
249 }
250 
251 static int
252 umct_attach(device_t dev)
253 {
254 	struct usb_attach_arg *uaa = device_get_ivars(dev);
255 	struct umct_softc *sc = device_get_softc(dev);
256 	int32_t error;
257 	uint16_t maxp;
258 	uint8_t iface_index;
259 
260 	sc->sc_udev = uaa->device;
261 	sc->sc_unit = device_get_unit(dev);
262 
263 	device_set_usb_desc(dev);
264 	mtx_init(&sc->sc_mtx, "umct", NULL, MTX_DEF);
265 	ucom_ref(&sc->sc_super_ucom);
266 
267 	sc->sc_iface_no = uaa->info.bIfaceNum;
268 
269 	iface_index = UMCT_IFACE_INDEX;
270 	error = usbd_transfer_setup(uaa->device, &iface_index,
271 	    sc->sc_xfer, umct_config, UMCT_N_TRANSFER, sc, &sc->sc_mtx);
272 
273 	if (error) {
274 		device_printf(dev, "allocating USB "
275 		    "transfers failed\n");
276 		goto detach;
277 	}
278 
279 	/*
280 	 * The real bulk-in endpoint is also marked as an interrupt.
281 	 * The only way to differentiate it from the real interrupt
282 	 * endpoint is to look at the wMaxPacketSize field.
283 	 */
284 	maxp = usbd_xfer_max_framelen(sc->sc_xfer[UMCT_BULK_DT_RD]);
285 	if (maxp == 0x2) {
286 		/* guessed wrong - switch around endpoints */
287 
288 		struct usb_xfer *temp = sc->sc_xfer[UMCT_INTR_DT_RD];
289 
290 		sc->sc_xfer[UMCT_INTR_DT_RD] = sc->sc_xfer[UMCT_BULK_DT_RD];
291 		sc->sc_xfer[UMCT_BULK_DT_RD] = temp;
292 		sc->sc_swap_cb = 1;
293 	}
294 
295 	sc->sc_obufsize = usbd_xfer_max_len(sc->sc_xfer[UMCT_BULK_DT_WR]);
296 
297 	if (uaa->info.idProduct == USB_PRODUCT_MCT_SITECOM_USB232) {
298 		if (sc->sc_obufsize > 16) {
299 			sc->sc_obufsize = 16;
300 		}
301 	}
302 	error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
303 	    &umct_callback, &sc->sc_mtx);
304 	if (error) {
305 		goto detach;
306 	}
307 	ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
308 
309 	return (0);			/* success */
310 
311 detach:
312 	umct_detach(dev);
313 	return (ENXIO);			/* failure */
314 }
315 
316 static int
317 umct_detach(device_t dev)
318 {
319 	struct umct_softc *sc = device_get_softc(dev);
320 
321 	ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
322 	usbd_transfer_unsetup(sc->sc_xfer, UMCT_N_TRANSFER);
323 
324 	device_claim_softc(dev);
325 
326 	umct_free_softc(sc);
327 
328 	return (0);
329 }
330 
331 UCOM_UNLOAD_DRAIN(umct);
332 
333 static void
334 umct_free_softc(struct umct_softc *sc)
335 {
336 	if (ucom_unref(&sc->sc_super_ucom)) {
337 		mtx_destroy(&sc->sc_mtx);
338 		device_free_softc(sc);
339 	}
340 }
341 
342 static void
343 umct_free(struct ucom_softc *ucom)
344 {
345 	umct_free_softc(ucom->sc_parent);
346 }
347 
348 static void
349 umct_cfg_do_request(struct umct_softc *sc, uint8_t request,
350     uint16_t len, uint32_t value)
351 {
352 	struct usb_device_request req;
353 	usb_error_t err;
354 	uint8_t temp[4];
355 
356 	if (len > 4)
357 		len = 4;
358 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
359 	req.bRequest = request;
360 	USETW(req.wValue, 0);
361 	req.wIndex[0] = sc->sc_iface_no;
362 	req.wIndex[1] = 0;
363 	USETW(req.wLength, len);
364 	USETDW(temp, value);
365 
366 	err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom,
367 	    &req, temp, 0, 1000);
368 	if (err) {
369 		DPRINTFN(0, "device request failed, err=%s "
370 		    "(ignored)\n", usbd_errstr(err));
371 	}
372 	return;
373 }
374 
375 static void
376 umct_intr_callback_sub(struct usb_xfer *xfer, usb_error_t error)
377 {
378 	struct umct_softc *sc = usbd_xfer_softc(xfer);
379 	struct usb_page_cache *pc;
380 	uint8_t buf[2];
381 	int actlen;
382 
383 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
384 
385 	switch (USB_GET_STATE(xfer)) {
386 	case USB_ST_TRANSFERRED:
387 		if (actlen < 2) {
388 			DPRINTF("too short message\n");
389 			goto tr_setup;
390 		}
391 		pc = usbd_xfer_get_frame(xfer, 0);
392 		usbd_copy_out(pc, 0, buf, sizeof(buf));
393 
394 		/*
395 		 * MSR bits need translation from ns16550 to SER_* values.
396 		 * LSR bits are ns16550 in hardware and ucom.
397 		 */
398 		sc->sc_msr = 0;
399 		if (buf[0] & UMCT_MSR_CTS)
400 			sc->sc_msr |= SER_CTS;
401 		if (buf[0] & UMCT_MSR_CD)
402 			sc->sc_msr |= SER_DCD;
403 		if (buf[0] & UMCT_MSR_RI)
404 			sc->sc_msr |= SER_RI;
405 		if (buf[0] & UMCT_MSR_RTS)
406 			sc->sc_msr |= SER_DSR;
407 		sc->sc_lsr = buf[1];
408 
409 		ucom_status_change(&sc->sc_ucom);
410 		/* FALLTHROUGH */
411 	case USB_ST_SETUP:
412 tr_setup:
413 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
414 		usbd_transfer_submit(xfer);
415 		return;
416 
417 	default:			/* Error */
418 		if (error != USB_ERR_CANCELLED) {
419 			/* try to clear stall first */
420 			usbd_xfer_set_stall(xfer);
421 			goto tr_setup;
422 		}
423 		return;
424 	}
425 }
426 
427 static void
428 umct_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
429 {
430 	struct umct_softc *sc = ucom->sc_parent;
431 
432 	*lsr = sc->sc_lsr;
433 	*msr = sc->sc_msr;
434 }
435 
436 static void
437 umct_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
438 {
439 	struct umct_softc *sc = ucom->sc_parent;
440 
441 	if (onoff)
442 		sc->sc_lcr |= 0x40;
443 	else
444 		sc->sc_lcr &= ~0x40;
445 
446 	umct_cfg_do_request(sc, UMCT_SET_LCR, UMCT_SET_LCR_SIZE, sc->sc_lcr);
447 }
448 
449 static void
450 umct_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
451 {
452 	struct umct_softc *sc = ucom->sc_parent;
453 
454 	if (onoff)
455 		sc->sc_mcr |= 0x01;
456 	else
457 		sc->sc_mcr &= ~0x01;
458 
459 	umct_cfg_do_request(sc, UMCT_SET_MCR, UMCT_SET_MCR_SIZE, sc->sc_mcr);
460 }
461 
462 static void
463 umct_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
464 {
465 	struct umct_softc *sc = ucom->sc_parent;
466 
467 	if (onoff)
468 		sc->sc_mcr |= 0x02;
469 	else
470 		sc->sc_mcr &= ~0x02;
471 
472 	umct_cfg_do_request(sc, UMCT_SET_MCR, UMCT_SET_MCR_SIZE, sc->sc_mcr);
473 }
474 
475 static uint8_t
476 umct_calc_baud(uint32_t baud)
477 {
478 	switch (baud) {
479 	case B300:
480 		return (0x1);
481 	case B600:
482 		return (0x2);
483 	case B1200:
484 		return (0x3);
485 	case B2400:
486 		return (0x4);
487 	case B4800:
488 		return (0x6);
489 	case B9600:
490 		return (0x8);
491 	case B19200:
492 		return (0x9);
493 	case B38400:
494 		return (0xa);
495 	case B57600:
496 		return (0xb);
497 	case 115200:
498 		return (0xc);
499 	case B0:
500 	default:
501 		break;
502 	}
503 	return (0x0);
504 }
505 
506 static int
507 umct_pre_param(struct ucom_softc *ucom, struct termios *t)
508 {
509 	return (0);			/* we accept anything */
510 }
511 
512 static void
513 umct_cfg_param(struct ucom_softc *ucom, struct termios *t)
514 {
515 	struct umct_softc *sc = ucom->sc_parent;
516 	uint32_t value;
517 
518 	value = umct_calc_baud(t->c_ospeed);
519 	umct_cfg_do_request(sc, UMCT_SET_BAUD, UMCT_SET_BAUD_SIZE, value);
520 
521 	value = (sc->sc_lcr & 0x40);
522 
523 	switch (t->c_cflag & CSIZE) {
524 	case CS5:
525 		value |= 0x0;
526 		break;
527 	case CS6:
528 		value |= 0x1;
529 		break;
530 	case CS7:
531 		value |= 0x2;
532 		break;
533 	default:
534 	case CS8:
535 		value |= 0x3;
536 		break;
537 	}
538 
539 	value |= (t->c_cflag & CSTOPB) ? 0x4 : 0;
540 	if (t->c_cflag & PARENB) {
541 		value |= 0x8;
542 		value |= (t->c_cflag & PARODD) ? 0x0 : 0x10;
543 	}
544 	/*
545 	 * XXX There doesn't seem to be a way to tell the device
546 	 * to use flow control.
547 	 */
548 
549 	sc->sc_lcr = value;
550 	umct_cfg_do_request(sc, UMCT_SET_LCR, UMCT_SET_LCR_SIZE, value);
551 }
552 
553 static void
554 umct_start_read(struct ucom_softc *ucom)
555 {
556 	struct umct_softc *sc = ucom->sc_parent;
557 
558 	/* start interrupt endpoint */
559 	usbd_transfer_start(sc->sc_xfer[UMCT_INTR_DT_RD]);
560 
561 	/* start read endpoint */
562 	usbd_transfer_start(sc->sc_xfer[UMCT_BULK_DT_RD]);
563 }
564 
565 static void
566 umct_stop_read(struct ucom_softc *ucom)
567 {
568 	struct umct_softc *sc = ucom->sc_parent;
569 
570 	/* stop interrupt endpoint */
571 	usbd_transfer_stop(sc->sc_xfer[UMCT_INTR_DT_RD]);
572 
573 	/* stop read endpoint */
574 	usbd_transfer_stop(sc->sc_xfer[UMCT_BULK_DT_RD]);
575 }
576 
577 static void
578 umct_start_write(struct ucom_softc *ucom)
579 {
580 	struct umct_softc *sc = ucom->sc_parent;
581 
582 	usbd_transfer_start(sc->sc_xfer[UMCT_BULK_DT_WR]);
583 }
584 
585 static void
586 umct_stop_write(struct ucom_softc *ucom)
587 {
588 	struct umct_softc *sc = ucom->sc_parent;
589 
590 	usbd_transfer_stop(sc->sc_xfer[UMCT_BULK_DT_WR]);
591 }
592 
593 static void
594 umct_read_callback(struct usb_xfer *xfer, usb_error_t error)
595 {
596 	struct umct_softc *sc = usbd_xfer_softc(xfer);
597 
598 	if (sc->sc_swap_cb)
599 		umct_intr_callback_sub(xfer, error);
600 	else
601 		umct_read_callback_sub(xfer, error);
602 }
603 
604 static void
605 umct_intr_callback(struct usb_xfer *xfer, usb_error_t error)
606 {
607 	struct umct_softc *sc = usbd_xfer_softc(xfer);
608 
609 	if (sc->sc_swap_cb)
610 		umct_read_callback_sub(xfer, error);
611 	else
612 		umct_intr_callback_sub(xfer, error);
613 }
614 
615 static void
616 umct_write_callback(struct usb_xfer *xfer, usb_error_t error)
617 {
618 	struct umct_softc *sc = usbd_xfer_softc(xfer);
619 	struct usb_page_cache *pc;
620 	uint32_t actlen;
621 
622 	switch (USB_GET_STATE(xfer)) {
623 	case USB_ST_SETUP:
624 	case USB_ST_TRANSFERRED:
625 tr_setup:
626 		pc = usbd_xfer_get_frame(xfer, 0);
627 		if (ucom_get_data(&sc->sc_ucom, pc, 0,
628 		    sc->sc_obufsize, &actlen)) {
629 			usbd_xfer_set_frame_len(xfer, 0, actlen);
630 			usbd_transfer_submit(xfer);
631 		}
632 		return;
633 
634 	default:			/* Error */
635 		if (error != USB_ERR_CANCELLED) {
636 			/* try to clear stall first */
637 			usbd_xfer_set_stall(xfer);
638 			goto tr_setup;
639 		}
640 		return;
641 	}
642 }
643 
644 static void
645 umct_read_callback_sub(struct usb_xfer *xfer, usb_error_t error)
646 {
647 	struct umct_softc *sc = usbd_xfer_softc(xfer);
648 	struct usb_page_cache *pc;
649 	int actlen;
650 
651 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
652 
653 	switch (USB_GET_STATE(xfer)) {
654 	case USB_ST_TRANSFERRED:
655 		pc = usbd_xfer_get_frame(xfer, 0);
656 		ucom_put_data(&sc->sc_ucom, pc, 0, actlen);
657 
658 	case USB_ST_SETUP:
659 tr_setup:
660 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
661 		usbd_transfer_submit(xfer);
662 		return;
663 
664 	default:			/* Error */
665 		if (error != USB_ERR_CANCELLED) {
666 			/* try to clear stall first */
667 			usbd_xfer_set_stall(xfer);
668 			goto tr_setup;
669 		}
670 		return;
671 	}
672 }
673 
674 static void
675 umct_poll(struct ucom_softc *ucom)
676 {
677 	struct umct_softc *sc = ucom->sc_parent;
678 	usbd_transfer_poll(sc->sc_xfer, UMCT_N_TRANSFER);
679 }
680