xref: /netbsd-src/sys/dev/usb/uftdi.c (revision de1dfb1250df962f1ff3a011772cf58e605aed11)
1 /*	$NetBSD: uftdi.c,v 1.22 2004/09/13 12:55:49 drochner Exp $	*/
2 
3 /*
4  * Copyright (c) 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Lennart Augustsson (lennart@augustsson.net).
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * FTDI FT8U100AX serial adapter driver
41  */
42 
43 /*
44  * XXX This driver will not support multiple serial ports.
45  * XXX The ucom layer needs to be extended first.
46  */
47 
48 #include <sys/cdefs.h>
49 __KERNEL_RCSID(0, "$NetBSD: uftdi.c,v 1.22 2004/09/13 12:55:49 drochner Exp $");
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/kernel.h>
54 #include <sys/device.h>
55 #include <sys/conf.h>
56 #include <sys/tty.h>
57 
58 #include <dev/usb/usb.h>
59 #include <dev/usb/usbhid.h>
60 
61 #include <dev/usb/usbdi.h>
62 #include <dev/usb/usbdi_util.h>
63 #include <dev/usb/usbdevs.h>
64 
65 #include <dev/usb/ucomvar.h>
66 
67 #include <dev/usb/uftdireg.h>
68 
69 #ifdef UFTDI_DEBUG
70 #define DPRINTF(x)	if (uftdidebug) printf x
71 #define DPRINTFN(n,x)	if (uftdidebug>(n)) printf x
72 int uftdidebug = 0;
73 #else
74 #define DPRINTF(x)
75 #define DPRINTFN(n,x)
76 #endif
77 
78 #define UFTDI_CONFIG_INDEX	0
79 #define UFTDI_IFACE_INDEX	0
80 
81 
82 /*
83  * These are the maximum number of bytes transferred per frame.
84  * The output buffer size cannot be increased due to the size encoding.
85  */
86 #define UFTDIIBUFSIZE 64
87 #define UFTDIOBUFSIZE 64
88 
89 struct uftdi_softc {
90 	USBBASEDEVICE		sc_dev;		/* base device */
91 	usbd_device_handle	sc_udev;	/* device */
92 	usbd_interface_handle	sc_iface;	/* interface */
93 
94 	enum uftdi_type		sc_type;
95 	u_int			sc_hdrlen;
96 
97 	u_char			sc_msr;
98 	u_char			sc_lsr;
99 
100 	device_ptr_t		sc_subdev;
101 
102 	u_char			sc_dying;
103 
104 	u_int			last_lcr;
105 };
106 
107 Static void	uftdi_get_status(void *, int portno, u_char *lsr, u_char *msr);
108 Static void	uftdi_set(void *, int, int, int);
109 Static int	uftdi_param(void *, int, struct termios *);
110 Static int	uftdi_open(void *sc, int portno);
111 Static void	uftdi_read(void *sc, int portno, u_char **ptr,u_int32_t *count);
112 Static void	uftdi_write(void *sc, int portno, u_char *to, u_char *from,
113 			    u_int32_t *count);
114 Static void	uftdi_break(void *sc, int portno, int onoff);
115 
116 struct ucom_methods uftdi_methods = {
117 	uftdi_get_status,
118 	uftdi_set,
119 	uftdi_param,
120 	NULL,
121 	uftdi_open,
122 	NULL,
123 	uftdi_read,
124 	uftdi_write,
125 };
126 
127 USB_DECLARE_DRIVER(uftdi);
128 
129 USB_MATCH(uftdi)
130 {
131 	USB_MATCH_START(uftdi, uaa);
132 
133 	if (uaa->iface != NULL)
134 		return (UMATCH_NONE);
135 
136 	DPRINTFN(20,("uftdi: vendor=0x%x, product=0x%x\n",
137 		     uaa->vendor, uaa->product));
138 
139 	if (uaa->vendor == USB_VENDOR_FTDI &&
140 	    (uaa->product == USB_PRODUCT_FTDI_SERIAL_8U100AX ||
141 	     uaa->product == USB_PRODUCT_FTDI_SERIAL_8U232AM ||
142 	     uaa->product == USB_PRODUCT_FTDI_SEMC_DSS20 ||
143 	     uaa->product == USB_PRODUCT_FTDI_LCD_LK202_24_USB ||
144 	     uaa->product == USB_PRODUCT_FTDI_LCD_MX200_USB ||
145 	     uaa->product == USB_PRODUCT_FTDI_CFA_631))
146 		return (UMATCH_VENDOR_PRODUCT);
147 
148 	return (UMATCH_NONE);
149 }
150 
151 USB_ATTACH(uftdi)
152 {
153 	USB_ATTACH_START(uftdi, sc, uaa);
154 	usbd_device_handle dev = uaa->device;
155 	usbd_interface_handle iface;
156 	usb_interface_descriptor_t *id;
157 	usb_endpoint_descriptor_t *ed;
158 	char devinfo[1024];
159 	char *devname = USBDEVNAME(sc->sc_dev);
160 	int i;
161 	usbd_status err;
162 	struct ucom_attach_args uca;
163 
164 	DPRINTFN(10,("\nuftdi_attach: sc=%p\n", sc));
165 
166 	/* Move the device into the configured state. */
167 	err = usbd_set_config_index(dev, UFTDI_CONFIG_INDEX, 1);
168 	if (err) {
169 		printf("\n%s: failed to set configuration, err=%s\n",
170 		       devname, usbd_errstr(err));
171 		goto bad;
172 	}
173 
174 	err = usbd_device2interface_handle(dev, UFTDI_IFACE_INDEX, &iface);
175 	if (err) {
176 		printf("\n%s: failed to get interface, err=%s\n",
177 		       devname, usbd_errstr(err));
178 		goto bad;
179 	}
180 
181 	usbd_devinfo(dev, 0, devinfo, sizeof(devinfo));
182 	USB_ATTACH_SETUP;
183 	printf("%s: %s\n", devname, devinfo);
184 
185 	id = usbd_get_interface_descriptor(iface);
186 
187 	sc->sc_udev = dev;
188 	sc->sc_iface = iface;
189 
190 	switch (uaa->product) {
191 	case USB_PRODUCT_FTDI_SERIAL_8U100AX:
192 		sc->sc_type = UFTDI_TYPE_SIO;
193 		sc->sc_hdrlen = 1;
194 		break;
195 
196 	case USB_PRODUCT_FTDI_SEMC_DSS20:
197 	case USB_PRODUCT_FTDI_SERIAL_8U232AM:
198 	case USB_PRODUCT_FTDI_LCD_LK202_24_USB:
199 	case USB_PRODUCT_FTDI_LCD_MX200_USB:
200 	case USB_PRODUCT_FTDI_CFA_631:
201 		sc->sc_type = UFTDI_TYPE_8U232AM;
202 		sc->sc_hdrlen = 0;
203 		break;
204 
205 	default:		/* Can't happen */
206 		goto bad;
207 	}
208 
209 	uca.bulkin = uca.bulkout = -1;
210 	for (i = 0; i < id->bNumEndpoints; i++) {
211 		int addr, dir, attr;
212 		ed = usbd_interface2endpoint_descriptor(iface, i);
213 		if (ed == NULL) {
214 			printf("%s: could not read endpoint descriptor"
215 			       ": %s\n", devname, usbd_errstr(err));
216 			goto bad;
217 		}
218 
219 		addr = ed->bEndpointAddress;
220 		dir = UE_GET_DIR(ed->bEndpointAddress);
221 		attr = ed->bmAttributes & UE_XFERTYPE;
222 		if (dir == UE_DIR_IN && attr == UE_BULK)
223 			uca.bulkin = addr;
224 		else if (dir == UE_DIR_OUT && attr == UE_BULK)
225 			uca.bulkout = addr;
226 		else {
227 			printf("%s: unexpected endpoint\n", devname);
228 			goto bad;
229 		}
230 	}
231 	if (uca.bulkin == -1) {
232 		printf("%s: Could not find data bulk in\n",
233 		       USBDEVNAME(sc->sc_dev));
234 		goto bad;
235 	}
236 	if (uca.bulkout == -1) {
237 		printf("%s: Could not find data bulk out\n",
238 		       USBDEVNAME(sc->sc_dev));
239 		goto bad;
240 	}
241 
242 	uca.portno = FTDI_PIT_SIOA;
243 	/* bulkin, bulkout set above */
244 	uca.ibufsize = UFTDIIBUFSIZE;
245 	uca.obufsize = UFTDIOBUFSIZE - sc->sc_hdrlen;
246 	uca.ibufsizepad = UFTDIIBUFSIZE;
247 	uca.opkthdrlen = sc->sc_hdrlen;
248 	uca.device = dev;
249 	uca.iface = iface;
250 	uca.methods = &uftdi_methods;
251 	uca.arg = sc;
252 	uca.info = NULL;
253 
254 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev,
255 			   USBDEV(sc->sc_dev));
256 
257 	DPRINTF(("uftdi: in=0x%x out=0x%x\n", uca.bulkin, uca.bulkout));
258 	sc->sc_subdev = config_found_sm_loc(self, "ucombus", NULL, &uca,
259 					    ucomprint, ucomsubmatch);
260 
261 	USB_ATTACH_SUCCESS_RETURN;
262 
263 bad:
264 	DPRINTF(("uftdi_attach: ATTACH ERROR\n"));
265 	sc->sc_dying = 1;
266 	USB_ATTACH_ERROR_RETURN;
267 }
268 
269 int
270 uftdi_activate(device_ptr_t self, enum devact act)
271 {
272 	struct uftdi_softc *sc = (struct uftdi_softc *)self;
273 	int rv = 0;
274 
275 	switch (act) {
276 	case DVACT_ACTIVATE:
277 		return (EOPNOTSUPP);
278 
279 	case DVACT_DEACTIVATE:
280 		if (sc->sc_subdev != NULL)
281 			rv = config_deactivate(sc->sc_subdev);
282 		sc->sc_dying = 1;
283 		break;
284 	}
285 	return (rv);
286 }
287 
288 int
289 uftdi_detach(device_ptr_t self, int flags)
290 {
291 	struct uftdi_softc *sc = (struct uftdi_softc *)self;
292 
293 	DPRINTF(("uftdi_detach: sc=%p flags=%d\n", sc, flags));
294 	sc->sc_dying = 1;
295 	if (sc->sc_subdev != NULL) {
296 		config_detach(sc->sc_subdev, flags);
297 		sc->sc_subdev = NULL;
298 	}
299 
300 	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev,
301 			   USBDEV(sc->sc_dev));
302 
303 	return (0);
304 }
305 
306 Static int
307 uftdi_open(void *vsc, int portno)
308 {
309 	struct uftdi_softc *sc = vsc;
310 	usb_device_request_t req;
311 	usbd_status err;
312 	struct termios t;
313 
314 	DPRINTF(("uftdi_open: sc=%p\n", sc));
315 
316 	if (sc->sc_dying)
317 		return (EIO);
318 
319 	/* Perform a full reset on the device */
320 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
321 	req.bRequest = FTDI_SIO_RESET;
322 	USETW(req.wValue, FTDI_SIO_RESET_SIO);
323 	USETW(req.wIndex, portno);
324 	USETW(req.wLength, 0);
325 	err = usbd_do_request(sc->sc_udev, &req, NULL);
326 	if (err)
327 		return (EIO);
328 
329 	/* Set 9600 baud, 2 stop bits, no parity, 8 bits */
330 	t.c_ospeed = 9600;
331 	t.c_cflag = CSTOPB | CS8;
332 	(void)uftdi_param(sc, portno, &t);
333 
334 	/* Turn on RTS/CTS flow control */
335 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
336 	req.bRequest = FTDI_SIO_SET_FLOW_CTRL;
337 	USETW(req.wValue, 0);
338 	USETW2(req.wIndex, FTDI_SIO_RTS_CTS_HS, portno);
339 	USETW(req.wLength, 0);
340 	err = usbd_do_request(sc->sc_udev, &req, NULL);
341 	if (err)
342 		return (EIO);
343 
344 	return (0);
345 }
346 
347 Static void
348 uftdi_read(void *vsc, int portno, u_char **ptr, u_int32_t *count)
349 {
350 	struct uftdi_softc *sc = vsc;
351 	u_char msr, lsr;
352 
353 	DPRINTFN(15,("uftdi_read: sc=%p, port=%d count=%d\n", sc, portno,
354 		     *count));
355 
356 	msr = FTDI_GET_MSR(*ptr);
357 	lsr = FTDI_GET_LSR(*ptr);
358 
359 #ifdef UFTDI_DEBUG
360 	if (*count != 2)
361 		DPRINTFN(10,("uftdi_read: sc=%p, port=%d count=%d data[0]="
362 			    "0x%02x\n", sc, portno, *count, (*ptr)[2]));
363 #endif
364 
365 	if (sc->sc_msr != msr ||
366 	    (sc->sc_lsr & FTDI_LSR_MASK) != (lsr & FTDI_LSR_MASK)) {
367 		DPRINTF(("uftdi_read: status change msr=0x%02x(0x%02x) "
368 			 "lsr=0x%02x(0x%02x)\n", msr, sc->sc_msr,
369 			 lsr, sc->sc_lsr));
370 		sc->sc_msr = msr;
371 		sc->sc_lsr = lsr;
372 		ucom_status_change((struct ucom_softc *)sc->sc_subdev);
373 	}
374 
375 	/* Pick up status and adjust data part. */
376 	*ptr += 2;
377 	*count -= 2;
378 }
379 
380 Static void
381 uftdi_write(void *vsc, int portno, u_char *to, u_char *from, u_int32_t *count)
382 {
383 	struct uftdi_softc *sc = vsc;
384 
385 	DPRINTFN(10,("uftdi_write: sc=%p, port=%d count=%u data[0]=0x%02x\n",
386 		     vsc, portno, *count, from[0]));
387 
388 	/* Make length tag and copy data */
389 	if (sc->sc_hdrlen > 0)
390 		*to = FTDI_OUT_TAG(*count, portno);
391 
392 	memcpy(to + sc->sc_hdrlen, from, *count);
393 	*count += sc->sc_hdrlen;
394 }
395 
396 Static void
397 uftdi_set(void *vsc, int portno, int reg, int onoff)
398 {
399 	struct uftdi_softc *sc = vsc;
400 	usb_device_request_t req;
401 	int ctl;
402 
403 	DPRINTF(("uftdi_set: sc=%p, port=%d reg=%d onoff=%d\n", vsc, portno,
404 		 reg, onoff));
405 
406 	switch (reg) {
407 	case UCOM_SET_DTR:
408 		ctl = onoff ? FTDI_SIO_SET_DTR_HIGH : FTDI_SIO_SET_DTR_LOW;
409 		break;
410 	case UCOM_SET_RTS:
411 		ctl = onoff ? FTDI_SIO_SET_RTS_HIGH : FTDI_SIO_SET_RTS_LOW;
412 		break;
413 	case UCOM_SET_BREAK:
414 		uftdi_break(sc, portno, onoff);
415 		return;
416 	default:
417 		return;
418 	}
419 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
420 	req.bRequest = FTDI_SIO_MODEM_CTRL;
421 	USETW(req.wValue, ctl);
422 	USETW(req.wIndex, portno);
423 	USETW(req.wLength, 0);
424 	DPRINTFN(2,("uftdi_set: reqtype=0x%02x req=0x%02x value=0x%04x "
425 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
426 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
427 	(void)usbd_do_request(sc->sc_udev, &req, NULL);
428 }
429 
430 Static int
431 uftdi_param(void *vsc, int portno, struct termios *t)
432 {
433 	struct uftdi_softc *sc = vsc;
434 	usb_device_request_t req;
435 	usbd_status err;
436 	int rate, data, flow;
437 
438 	DPRINTF(("uftdi_param: sc=%p\n", sc));
439 
440 	if (sc->sc_dying)
441 		return (EIO);
442 
443 	switch (sc->sc_type) {
444 	case UFTDI_TYPE_SIO:
445 		switch (t->c_ospeed) {
446 		case 300: rate = ftdi_sio_b300; break;
447 		case 600: rate = ftdi_sio_b600; break;
448 		case 1200: rate = ftdi_sio_b1200; break;
449 		case 2400: rate = ftdi_sio_b2400; break;
450 		case 4800: rate = ftdi_sio_b4800; break;
451 		case 9600: rate = ftdi_sio_b9600; break;
452 		case 19200: rate = ftdi_sio_b19200; break;
453 		case 38400: rate = ftdi_sio_b38400; break;
454 		case 57600: rate = ftdi_sio_b57600; break;
455 		case 115200: rate = ftdi_sio_b115200; break;
456 		default:
457 			return (EINVAL);
458 		}
459 		break;
460 
461 	case UFTDI_TYPE_8U232AM:
462 		switch(t->c_ospeed) {
463 		case 300: rate = ftdi_8u232am_b300; break;
464 		case 600: rate = ftdi_8u232am_b600; break;
465 		case 1200: rate = ftdi_8u232am_b1200; break;
466 		case 2400: rate = ftdi_8u232am_b2400; break;
467 		case 4800: rate = ftdi_8u232am_b4800; break;
468 		case 9600: rate = ftdi_8u232am_b9600; break;
469 		case 19200: rate = ftdi_8u232am_b19200; break;
470 		case 38400: rate = ftdi_8u232am_b38400; break;
471 		case 57600: rate = ftdi_8u232am_b57600; break;
472 		case 115200: rate = ftdi_8u232am_b115200; break;
473 		case 230400: rate = ftdi_8u232am_b230400; break;
474 		case 460800: rate = ftdi_8u232am_b460800; break;
475 		case 921600: rate = ftdi_8u232am_b921600; break;
476 		default:
477 			return (EINVAL);
478 		}
479 		break;
480 
481 	default:
482 		return (EINVAL);
483 	}
484 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
485 	req.bRequest = FTDI_SIO_SET_BAUD_RATE;
486 	USETW(req.wValue, rate);
487 	USETW(req.wIndex, portno);
488 	USETW(req.wLength, 0);
489 	DPRINTFN(2,("uftdi_param: reqtype=0x%02x req=0x%02x value=0x%04x "
490 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
491 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
492 	err = usbd_do_request(sc->sc_udev, &req, NULL);
493 	if (err)
494 		return (EIO);
495 
496 	if (ISSET(t->c_cflag, CSTOPB))
497 		data = FTDI_SIO_SET_DATA_STOP_BITS_2;
498 	else
499 		data = FTDI_SIO_SET_DATA_STOP_BITS_1;
500 	if (ISSET(t->c_cflag, PARENB)) {
501 		if (ISSET(t->c_cflag, PARODD))
502 			data |= FTDI_SIO_SET_DATA_PARITY_ODD;
503 		else
504 			data |= FTDI_SIO_SET_DATA_PARITY_EVEN;
505 	} else
506 		data |= FTDI_SIO_SET_DATA_PARITY_NONE;
507 	switch (ISSET(t->c_cflag, CSIZE)) {
508 	case CS5:
509 		data |= FTDI_SIO_SET_DATA_BITS(5);
510 		break;
511 	case CS6:
512 		data |= FTDI_SIO_SET_DATA_BITS(6);
513 		break;
514 	case CS7:
515 		data |= FTDI_SIO_SET_DATA_BITS(7);
516 		break;
517 	case CS8:
518 		data |= FTDI_SIO_SET_DATA_BITS(8);
519 		break;
520 	}
521 	sc->last_lcr = data;
522 
523 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
524 	req.bRequest = FTDI_SIO_SET_DATA;
525 	USETW(req.wValue, data);
526 	USETW(req.wIndex, portno);
527 	USETW(req.wLength, 0);
528 	DPRINTFN(2,("uftdi_param: reqtype=0x%02x req=0x%02x value=0x%04x "
529 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
530 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
531 	err = usbd_do_request(sc->sc_udev, &req, NULL);
532 	if (err)
533 		return (EIO);
534 
535 	if (ISSET(t->c_cflag, CRTSCTS)) {
536 		flow = FTDI_SIO_RTS_CTS_HS;
537 		USETW(req.wValue, 0);
538 	} else if (ISSET(t->c_iflag, IXON|IXOFF)) {
539 		flow = FTDI_SIO_XON_XOFF_HS;
540 		USETW2(req.wValue, t->c_cc[VSTOP], t->c_cc[VSTART]);
541 	} else {
542 		flow = FTDI_SIO_DISABLE_FLOW_CTRL;
543 		USETW(req.wValue, 0);
544 	}
545 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
546 	req.bRequest = FTDI_SIO_SET_FLOW_CTRL;
547 	USETW2(req.wIndex, flow, portno);
548 	USETW(req.wLength, 0);
549 	err = usbd_do_request(sc->sc_udev, &req, NULL);
550 	if (err)
551 		return (EIO);
552 
553 	return (0);
554 }
555 
556 void
557 uftdi_get_status(void *vsc, int portno, u_char *lsr, u_char *msr)
558 {
559 	struct uftdi_softc *sc = vsc;
560 
561 	DPRINTF(("uftdi_status: msr=0x%02x lsr=0x%02x\n",
562 		 sc->sc_msr, sc->sc_lsr));
563 
564 	if (msr != NULL)
565 		*msr = sc->sc_msr;
566 	if (lsr != NULL)
567 		*lsr = sc->sc_lsr;
568 }
569 
570 void
571 uftdi_break(void *vsc, int portno, int onoff)
572 {
573 	struct uftdi_softc *sc = vsc;
574 	usb_device_request_t req;
575 	int data;
576 
577 	DPRINTF(("uftdi_break: sc=%p, port=%d onoff=%d\n", vsc, portno,
578 		  onoff));
579 
580 	if (onoff) {
581 		data = sc->last_lcr | FTDI_SIO_SET_BREAK;
582 	} else {
583 		data = sc->last_lcr;
584 	}
585 
586 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
587 	req.bRequest = FTDI_SIO_SET_DATA;
588 	USETW(req.wValue, data);
589 	USETW(req.wIndex, portno);
590 	USETW(req.wLength, 0);
591 	(void)usbd_do_request(sc->sc_udev, &req, NULL);
592 }
593