xref: /netbsd-src/sys/dev/usb/uslsa.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /* $NetBSD: uslsa.c,v 1.30 2021/04/24 23:36:59 thorpej Exp $ */
2 
3 /* from ugensa.c */
4 
5 /*
6  * Copyright (c) 2004, 2005 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Roland C. Dowdeswell <elric@netbsd.org>.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
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.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * Copyright (c) 2007, 2009 Jonathan A. Kollasch.
36  * All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  *
47  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
48  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
50  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
51  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
52  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
53  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
54  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
55  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
56  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
57  *
58  */
59 
60 #include <sys/cdefs.h>
61 __KERNEL_RCSID(0, "$NetBSD: uslsa.c,v 1.30 2021/04/24 23:36:59 thorpej Exp $");
62 
63 #ifdef _KERNEL_OPT
64 #include "opt_usb.h"
65 #endif
66 
67 #include <sys/param.h>
68 #include <sys/systm.h>
69 #include <sys/kernel.h>
70 #include <sys/device.h>
71 #include <sys/conf.h>
72 #include <sys/tty.h>
73 
74 #include <dev/usb/usb.h>
75 
76 #include <dev/usb/usbdi.h>
77 #include <dev/usb/usbdi_util.h>
78 #include <dev/usb/usbdevs.h>
79 
80 #include <dev/usb/ucomvar.h>
81 
82 #include <dev/usb/uslsareg.h>
83 
84 #include <fs/unicode.h>
85 
86 #ifdef USLSA_DEBUG
87 #define DPRINTF(x)	if (uslsadebug) device_printf x
88 int uslsadebug = 0;
89 #else
90 #define DPRINTF(x)
91 #endif
92 
93 struct uslsa_softc {
94 	device_t		sc_dev;		/* base device */
95 	device_t		sc_subdev;	/* ucom device */
96 	struct usbd_device *	sc_udev;	/* usb device */
97 	struct usbd_interface *	sc_iface;	/* interface */
98 	uint8_t			sc_ifnum;	/* interface number */
99 	bool			sc_dying;	/* disconnecting */
100 };
101 
102 static void uslsa_get_status(void *sc, int, u_char *, u_char *);
103 static void uslsa_set(void *, int, int, int);
104 static int uslsa_param(void *, int, struct termios *);
105 static int uslsa_ioctl(void *, int, u_long, void *, int, proc_t *);
106 static int uslsa_open(void *, int);
107 static void uslsa_close(void *, int);
108 
109 static int uslsa_usbd_errno(usbd_status);
110 static int uslsa_request_set(struct uslsa_softc *, uint8_t, uint16_t);
111 static int uslsa_set_flow(struct uslsa_softc *, tcflag_t, tcflag_t);
112 
113 static const struct ucom_methods uslsa_methods = {
114 	.ucom_get_status = uslsa_get_status,
115 	.ucom_set = uslsa_set,
116 	.ucom_param = uslsa_param,
117 	.ucom_ioctl = uslsa_ioctl,
118 	.ucom_open = uslsa_open,
119 	.ucom_close = uslsa_close,
120 };
121 
122 #define USLSA_CONFIG_INDEX	0
123 #define USLSA_IFACE_INDEX	0
124 #define USLSA_BUFSIZE		256
125 
126 static const struct usb_devno uslsa_devs[] = {
127         { USB_VENDOR_BALTECH,           USB_PRODUCT_BALTECH_CARDREADER },
128         { USB_VENDOR_DYNASTREAM,        USB_PRODUCT_DYNASTREAM_ANTDEVBOARD },
129         { USB_VENDOR_JABLOTRON,         USB_PRODUCT_JABLOTRON_PC60B },
130         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_ARGUSISP },
131         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CRUMB128 },
132         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_DEGREECONT },
133         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_DESKTOPMOBILE },
134         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_IPLINK1220 },
135         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_HARP },
136         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_JTAG },
137         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_LIN },
138         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_POLOLU },
139         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CP210X_1 },
140         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CP210X_2 },
141         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_SUNNTO },
142         { USB_VENDOR_SILABS2,           USB_PRODUCT_SILABS2_DCU11CLONE },
143         { USB_VENDOR_USI,               USB_PRODUCT_USI_MC60 },
144 	{ USB_VENDOR_WMR,		USB_PRODUCT_WMR_RIGBLASTER },
145 };
146 
147 static int uslsa_match(device_t, cfdata_t, void *);
148 static void uslsa_attach(device_t, device_t, void *);
149 static void uslsa_childdet(device_t, device_t);
150 static int uslsa_detach(device_t, int);
151 
152 CFATTACH_DECL2_NEW(uslsa, sizeof(struct uslsa_softc), uslsa_match,
153     uslsa_attach, uslsa_detach, NULL, NULL, uslsa_childdet);
154 
155 static int
156 uslsa_match(device_t parent, cfdata_t match, void *aux)
157 {
158 	const struct usbif_attach_arg *uiaa = aux;
159 
160 	if (usb_lookup(uslsa_devs, uiaa->uiaa_vendor, uiaa->uiaa_product)
161 	    != NULL)
162 		return UMATCH_VENDOR_PRODUCT;
163 	else
164 		return UMATCH_NONE;
165 }
166 
167 static void
168 uslsa_attach(device_t parent, device_t self, void *aux)
169 {
170 	struct uslsa_softc *sc;
171 	const struct usbif_attach_arg *uiaa = aux;
172 	const usb_interface_descriptor_t *id;
173 	const usb_endpoint_descriptor_t *ed;
174 	char *devinfop;
175 	struct ucom_attach_args ucaa;
176 	int i;
177 
178 	sc = device_private(self);
179 
180 	sc->sc_dev = self;
181 	sc->sc_udev = uiaa->uiaa_device;
182 	sc->sc_iface = uiaa->uiaa_iface;
183 	sc->sc_dying = false;
184 
185 	aprint_naive("\n");
186 	aprint_normal("\n");
187 
188 	devinfop = usbd_devinfo_alloc(sc->sc_udev, 0);
189 	aprint_normal_dev(self, "%s\n", devinfop);
190 	usbd_devinfo_free(devinfop);
191 
192 	id = usbd_get_interface_descriptor(sc->sc_iface);
193 
194 	sc->sc_ifnum = id->bInterfaceNumber;
195 
196 	ucaa.ucaa_info = "Silicon Labs CP210x";
197 	ucaa.ucaa_portno = UCOM_UNK_PORTNO;
198 	ucaa.ucaa_ibufsize = USLSA_BUFSIZE;
199 	ucaa.ucaa_obufsize = USLSA_BUFSIZE;
200 	ucaa.ucaa_ibufsizepad = USLSA_BUFSIZE;
201 	ucaa.ucaa_opkthdrlen = 0;
202 	ucaa.ucaa_device = sc->sc_udev;
203 	ucaa.ucaa_iface = sc->sc_iface;
204 	ucaa.ucaa_methods = &uslsa_methods;
205 	ucaa.ucaa_arg = sc;
206 
207 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
208 
209 	ucaa.ucaa_bulkin = ucaa.ucaa_bulkout = -1;
210 	for (i = 0; i < id->bNumEndpoints; i++) {
211 		int addr, dir, attr;
212 
213 		ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
214 		if (ed == NULL) {
215 			aprint_error_dev(self,
216 			    "could not read endpoint descriptor\n");
217 			sc->sc_dying = true;
218 			return;
219 		}
220 		addr = ed->bEndpointAddress;
221 		dir = UE_GET_DIR(ed->bEndpointAddress);
222 		attr = ed->bmAttributes & UE_XFERTYPE;
223 		if (dir == UE_DIR_IN && attr == UE_BULK) {
224 			ucaa.ucaa_bulkin = addr;
225 		} else if (dir == UE_DIR_OUT && attr == UE_BULK) {
226 			ucaa.ucaa_bulkout = addr;
227 		} else {
228 			aprint_error_dev(self, "unexpected endpoint\n");
229 		}
230 	}
231 	aprint_debug_dev(sc->sc_dev, "EPs: in=%#x out=%#x\n",
232 		ucaa.ucaa_bulkin, ucaa.ucaa_bulkout);
233 	if ((ucaa.ucaa_bulkin == -1) || (ucaa.ucaa_bulkout == -1)) {
234 		aprint_error_dev(self, "could not find endpoints\n");
235 		sc->sc_dying = true;
236 		return;
237 	}
238 
239 	sc->sc_subdev = config_found(self, &ucaa, ucomprint,
240 				     CFARG_SUBMATCH, ucomsubmatch,
241 				     CFARG_EOL);
242 
243 	if (!pmf_device_register(self, NULL, NULL))
244 		aprint_error_dev(self, "couldn't establish power handler\n");
245 
246 	return;
247 }
248 
249 static void
250 uslsa_childdet(device_t self, device_t child)
251 {
252 	struct uslsa_softc *sc = device_private(self);
253 
254 	KASSERT(sc->sc_subdev == child);
255 	sc->sc_subdev = NULL;
256 }
257 
258 static int
259 uslsa_detach(device_t self, int flags)
260 {
261 	struct uslsa_softc *sc = device_private(self);
262 	int rv = 0;
263 
264 	DPRINTF((self, "%s(%p, %#x)\n", __func__, self, flags));
265 
266 	sc->sc_dying = true;
267 
268 	if (sc->sc_subdev != NULL) {
269 		rv = config_detach(sc->sc_subdev, flags);
270 		sc->sc_subdev = NULL;
271 	}
272 
273 	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);
274 
275 	return rv;
276 }
277 
278 static int
279 uslsa_usbd_errno(usbd_status status)
280 {
281 	switch (status) {
282 	case USBD_NORMAL_COMPLETION:
283 		return 0;
284 	case USBD_STALLED:
285 		return EINVAL;
286 	default:
287 		return EIO;
288 	}
289 }
290 
291 static void
292 uslsa_get_status(void *vsc, int portno, u_char *lsr, u_char *msr)
293 {
294 	struct uslsa_softc *sc;
295 	usb_device_request_t req;
296 	usbd_status status;
297 	uint8_t mdmsts;
298 
299 	sc = vsc;
300 
301 	DPRINTF((sc->sc_dev, "%s(%p, %d, ....)\n", __func__, vsc, portno));
302 
303 	if (sc->sc_dying)
304 		return;
305 
306 	req.bmRequestType = UT_READ_VENDOR_INTERFACE;
307 	req.bRequest = SLSA_R_GET_MDMSTS;
308 	USETW(req.wValue, 0);
309 	USETW(req.wIndex, sc->sc_ifnum);
310 	USETW(req.wLength, SLSA_RL_GET_MDMSTS);
311 
312 	status = usbd_do_request(sc->sc_udev, &req, &mdmsts);
313 	if (status != USBD_NORMAL_COMPLETION) {
314 		device_printf(sc->sc_dev, "%s: GET_MDMSTS %s\n",
315 		    __func__, usbd_errstr(status));
316 		return;
317 	}
318 
319 	DPRINTF((sc->sc_dev, "%s: GET_MDMSTS %#x\n", __func__, mdmsts));
320 
321 	*lsr = 0;
322 
323 	*msr  = ISSET(mdmsts, SLSA_MDMSTS_CTS) ? UMSR_CTS : 0;
324 	*msr |= ISSET(mdmsts, SLSA_MDMSTS_DSR) ? UMSR_DSR : 0;
325 	*msr |= ISSET(mdmsts, SLSA_MDMSTS_RI) ? UMSR_RI : 0;
326 	*msr |= ISSET(mdmsts, SLSA_MDMSTS_DCD) ? UMSR_DCD : 0;
327 }
328 
329 static void
330 uslsa_set(void *vsc, int portno, int reg, int onoff)
331 {
332 	struct uslsa_softc *sc;
333 
334 	sc = vsc;
335 
336 	DPRINTF((sc->sc_dev, "%s(%p, %d, %d, %d)\n", __func__, vsc, portno,
337 	    reg, onoff));
338 
339 	if (sc->sc_dying)
340 		return;
341 
342 	switch (reg) {
343 	case UCOM_SET_DTR:
344 		if (uslsa_request_set(sc, SLSA_R_SET_MHS,
345 		    SLSA_RV_SET_MHS_DTR_MASK |
346 		    (onoff ? SLSA_RV_SET_MHS_DTR : 0))) {
347 			device_printf(sc->sc_dev, "SET_MHS/DTR failed\n");
348 		}
349 		break;
350 	case UCOM_SET_RTS:
351 		if (uslsa_request_set(sc, SLSA_R_SET_MHS,
352 		    SLSA_RV_SET_MHS_RTS_MASK |
353 		    (onoff ? SLSA_RV_SET_MHS_RTS : 0))) {
354 			device_printf(sc->sc_dev, "SET_MHS/RTS failed\n");
355 		}
356 		break;
357 	case UCOM_SET_BREAK:
358 		if (uslsa_request_set(sc, SLSA_R_SET_BREAK,
359 		    (onoff ? SLSA_RV_SET_BREAK_ENABLE :
360 		     SLSA_RV_SET_BREAK_DISABLE))) {
361 			device_printf(sc->sc_dev, "SET_BREAK failed\n");
362 		}
363 		break;
364 	default:
365 		break;
366 	}
367 }
368 
369 static int
370 uslsa_param(void *vsc, int portno, struct termios *t)
371 {
372 	struct uslsa_softc *sc;
373 	usb_device_request_t req;
374 	usbd_status status;
375 	uint16_t value;
376 	uint32_t baud;
377 	int ret;
378 
379 	sc = vsc;
380 
381 	DPRINTF((sc->sc_dev, "%s(%p, %d, %p)\n", __func__, vsc, portno, t));
382 
383 	if (sc->sc_dying)
384 		return EIO;
385 
386 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
387 	req.bRequest = SLSA_R_SET_BAUDRATE;
388 	USETW(req.wValue, 0);
389 	USETW(req.wIndex, sc->sc_ifnum);
390 	USETW(req.wLength, 4);
391 
392 	baud = t->c_ospeed;
393 	status = usbd_do_request(sc->sc_udev, &req, &baud);
394 	if (status != USBD_NORMAL_COMPLETION) {
395 		/* fallback method for devices that don't know SET_BAUDRATE */
396 		/* hope we calculate it right */
397 		device_printf(sc->sc_dev, "%s: set baudrate %d, failed %s,"
398 				" using set bauddiv\n",
399 		    __func__, baud, usbd_errstr(status));
400 
401 		value = SLSA_RV_BAUDDIV(t->c_ospeed);
402 		if ((ret = uslsa_request_set(sc, SLSA_R_SET_BAUDDIV, value))
403 		    != 0) {
404 			device_printf(sc->sc_dev, "%s: SET_BAUDDIV failed\n",
405 			       __func__);
406 			return ret;
407 		}
408 	}
409 
410 	value = 0;
411 
412 	if (ISSET(t->c_cflag, CSTOPB)) {
413 		value |= SLSA_RV_LINE_CTL_STOP_2;
414 	} else {
415 		value |= SLSA_RV_LINE_CTL_STOP_1;
416 	}
417 
418 	if (ISSET(t->c_cflag, PARENB)) {
419 		if (ISSET(t->c_cflag, PARODD)) {
420 			value |= SLSA_RV_LINE_CTL_PARITY_ODD;
421 		} else {
422 			value |= SLSA_RV_LINE_CTL_PARITY_EVEN;
423 		}
424 	} else {
425 		value |= SLSA_RV_LINE_CTL_PARITY_NONE;
426 	}
427 
428 	switch (ISSET(t->c_cflag, CSIZE)) {
429 	case CS5:
430 		value |= SLSA_RV_LINE_CTL_LEN_5;
431 		break;
432 	case CS6:
433 		value |= SLSA_RV_LINE_CTL_LEN_6;
434 		break;
435 	case CS7:
436 		value |= SLSA_RV_LINE_CTL_LEN_7;
437 		break;
438 	case CS8:
439 		value |= SLSA_RV_LINE_CTL_LEN_8;
440 		break;
441 	}
442 
443 	DPRINTF((sc->sc_dev, "%s: setting LINE_CTL to %#x\n",
444 	    __func__, value));
445 	if ((ret = uslsa_request_set(sc, SLSA_R_SET_LINE_CTL, value)) != 0) {
446 		device_printf(sc->sc_dev, "SET_LINE_CTL failed\n");
447 		return ret;
448 	}
449 
450 	if ((ret = uslsa_set_flow(sc, t->c_cflag, t->c_iflag)) != 0) {
451 		device_printf(sc->sc_dev, "SET_LINE_CTL failed\n");
452 	}
453 
454 	return ret;
455 }
456 
457 static int
458 uslsa_ioctl(void *vsc, int portno, u_long cmd, void *data, int flag, proc_t *p)
459 {
460 	struct uslsa_softc *sc;
461 
462 	sc = vsc;
463 
464 	if (sc->sc_dying)
465 		return EIO;
466 
467 	switch (cmd) {
468 	case TIOCMGET:
469 		ucom_status_change(device_private(sc->sc_subdev));
470 		return EPASSTHROUGH;
471 	default:
472 		return EPASSTHROUGH;
473 	}
474 
475 	return 0;
476 }
477 
478 static int
479 uslsa_open(void *vsc, int portno)
480 {
481 	struct uslsa_softc *sc;
482 
483 	sc = vsc;
484 
485 	DPRINTF((sc->sc_dev, "%s(%p, %d)\n", __func__, vsc, portno));
486 
487 	if (sc->sc_dying)
488 		return EIO;
489 
490 	return uslsa_request_set(sc, SLSA_R_IFC_ENABLE,
491 	    SLSA_RV_IFC_ENABLE_ENABLE);
492 }
493 
494 static void
495 uslsa_close(void *vsc, int portno)
496 {
497 	struct uslsa_softc *sc;
498 
499 	sc = vsc;
500 
501 	DPRINTF((sc->sc_dev, "%s(%p, %d)\n", __func__, vsc, portno));
502 
503 	if (sc->sc_dying)
504 		return;
505 
506 	uslsa_request_set(sc, SLSA_R_IFC_ENABLE, SLSA_RV_IFC_ENABLE_DISABLE);
507 }
508 
509 static int
510 uslsa_request_set(struct uslsa_softc * sc, uint8_t request, uint16_t value)
511 {
512 	usb_device_request_t req;
513 	usbd_status status;
514 
515 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
516 	req.bRequest = request;
517 	USETW(req.wValue, value);
518 	USETW(req.wIndex, sc->sc_ifnum);
519 	USETW(req.wLength, 0);
520 
521 	status = usbd_do_request(sc->sc_udev, &req, NULL);
522 
523 	return uslsa_usbd_errno(status);
524 }
525 
526 static int
527 uslsa_set_flow(struct uslsa_softc *sc, tcflag_t cflag, tcflag_t iflag)
528 {
529 	struct slsa_fcs fcs;
530 	usb_device_request_t req;
531 	uint32_t ulControlHandshake;
532 	uint32_t ulFlowReplace;
533 	usbd_status status;
534 
535 	DPRINTF((sc->sc_dev, "%s(%p, %#x, %#x)\n", __func__, sc, cflag, iflag));
536 
537 	req.bmRequestType = UT_READ_VENDOR_INTERFACE;
538 	req.bRequest = SLSA_R_GET_FLOW;
539 	USETW(req.wValue, 0);
540 	USETW(req.wIndex, sc->sc_ifnum);
541 	USETW(req.wLength, SLSA_RL_GET_FLOW);
542 
543 	status = usbd_do_request(sc->sc_udev, &req, &fcs);
544 	if (status != USBD_NORMAL_COMPLETION) {
545 		device_printf(sc->sc_dev, "%s: GET_FLOW %s\n",
546 			__func__, usbd_errstr(status));
547 		return uslsa_usbd_errno(status);
548 	}
549 
550 	ulControlHandshake = le32toh(fcs.ulControlHandshake);
551 	ulFlowReplace = le32toh(fcs.ulFlowReplace);
552 
553 	if (ISSET(cflag, CRTSCTS)) {
554 		ulControlHandshake =
555 		    SERIAL_CTS_HANDSHAKE | __SHIFTIN(1, SERIAL_DTR_MASK);
556 		ulFlowReplace = __SHIFTIN(2, SERIAL_RTS_MASK);
557 	} else {
558 		ulControlHandshake = __SHIFTIN(1, SERIAL_DTR_MASK);
559 		ulFlowReplace = __SHIFTIN(1, SERIAL_RTS_MASK);
560 	}
561 
562 	fcs.ulControlHandshake = htole32(ulControlHandshake);
563 	fcs.ulFlowReplace = htole32(ulFlowReplace);
564 
565 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
566 	req.bRequest = SLSA_R_SET_FLOW;
567 	USETW(req.wValue, 0);
568 	USETW(req.wIndex, sc->sc_ifnum);
569 	USETW(req.wLength, SLSA_RL_SET_FLOW);
570 
571 	status = usbd_do_request(sc->sc_udev, &req, &fcs);
572 
573 	return uslsa_usbd_errno(status);
574 }
575