xref: /netbsd-src/sys/dev/usb/uslsa.c (revision c38e7cc395b1472a774ff828e46123de44c628e9)
1 /* $NetBSD: uslsa.c,v 1.25 2017/12/22 14:41:55 jakllsch 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 1.25 2017/12/22 14:41:55 jakllsch 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 
107 static int uslsa_open(void *, int);
108 static void uslsa_close(void *, int);
109 
110 static int uslsa_usbd_errno(usbd_status);
111 static int uslsa_request_set(struct uslsa_softc *, uint8_t, uint16_t);
112 static int uslsa_set_flow(struct uslsa_softc *, tcflag_t, tcflag_t);
113 
114 static const struct ucom_methods uslsa_methods = {
115 	.ucom_get_status = uslsa_get_status,
116 	.ucom_set = uslsa_set,
117 	.ucom_param = uslsa_param,
118 	.ucom_ioctl = uslsa_ioctl,
119 	.ucom_open = uslsa_open,
120 	.ucom_close = uslsa_close,
121 	.ucom_read = NULL,
122 	.ucom_write = NULL,
123 };
124 
125 #define USLSA_CONFIG_INDEX	0
126 #define USLSA_IFACE_INDEX	0
127 #define USLSA_BUFSIZE		256
128 
129 static const struct usb_devno uslsa_devs[] = {
130         { USB_VENDOR_BALTECH,           USB_PRODUCT_BALTECH_CARDREADER },
131         { USB_VENDOR_DYNASTREAM,        USB_PRODUCT_DYNASTREAM_ANTDEVBOARD },
132         { USB_VENDOR_JABLOTRON,         USB_PRODUCT_JABLOTRON_PC60B },
133         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_ARGUSISP },
134         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CRUMB128 },
135         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_DEGREECONT },
136         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_DESKTOPMOBILE },
137         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_IPLINK1220 },
138         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_HARP },
139         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_JTAG },
140         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_LIPOWSKY_LIN },
141         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_POLOLU },
142         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CP210X_1 },
143         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_CP210X_2 },
144         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_SUNNTO },
145         { USB_VENDOR_SILABS2,           USB_PRODUCT_SILABS2_DCU11CLONE },
146         { USB_VENDOR_USI,               USB_PRODUCT_USI_MC60 },
147 	{ USB_VENDOR_WMR,		USB_PRODUCT_WMR_RIGBLASTER },
148 };
149 
150 static int uslsa_match(device_t, cfdata_t, void *);
151 static void uslsa_attach(device_t, device_t, void *);
152 static void uslsa_childdet(device_t, device_t);
153 static int uslsa_detach(device_t, int);
154 static int uslsa_activate(device_t, enum devact);
155 
156 CFATTACH_DECL2_NEW(uslsa, sizeof(struct uslsa_softc), uslsa_match,
157     uslsa_attach, uslsa_detach, uslsa_activate, NULL, uslsa_childdet);
158 
159 static int
160 uslsa_match(device_t parent, cfdata_t match, void *aux)
161 {
162 	const struct usbif_attach_arg *uiaa = aux;
163 
164 	if (usb_lookup(uslsa_devs, uiaa->uiaa_vendor, uiaa->uiaa_product)
165 	    != NULL)
166 		return UMATCH_VENDOR_PRODUCT;
167 	else
168 		return UMATCH_NONE;
169 }
170 
171 static void
172 uslsa_attach(device_t parent, device_t self, void *aux)
173 {
174 	struct uslsa_softc *sc;
175 	const struct usbif_attach_arg *uiaa = aux;
176 	const usb_interface_descriptor_t *id;
177 	const usb_endpoint_descriptor_t *ed;
178 	char *devinfop;
179 	struct ucom_attach_args ucaa;
180 	int i;
181 
182 	sc = device_private(self);
183 
184 	sc->sc_dev = self;
185 	sc->sc_udev = uiaa->uiaa_device;
186 	sc->sc_iface = uiaa->uiaa_iface;
187 
188 	aprint_naive("\n");
189 	aprint_normal("\n");
190 
191 	devinfop = usbd_devinfo_alloc(sc->sc_udev, 0);
192 	aprint_normal_dev(self, "%s\n", devinfop);
193 	usbd_devinfo_free(devinfop);
194 
195 	id = usbd_get_interface_descriptor(sc->sc_iface);
196 
197 	sc->sc_ifnum = id->bInterfaceNumber;
198 
199 	ucaa.ucaa_info = "Silicon Labs CP210x";
200 	ucaa.ucaa_portno = UCOM_UNK_PORTNO;
201 	ucaa.ucaa_ibufsize = USLSA_BUFSIZE;
202 	ucaa.ucaa_obufsize = USLSA_BUFSIZE;
203 	ucaa.ucaa_ibufsizepad = USLSA_BUFSIZE;
204 	ucaa.ucaa_opkthdrlen = 0;
205 	ucaa.ucaa_device = sc->sc_udev;
206 	ucaa.ucaa_iface = sc->sc_iface;
207 	ucaa.ucaa_methods = &uslsa_methods;
208 	ucaa.ucaa_arg = sc;
209 
210 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
211 
212 	ucaa.ucaa_bulkin = ucaa.ucaa_bulkout = -1;
213 	for (i = 0; i < id->bNumEndpoints; i++) {
214 		int addr, dir, attr;
215 
216 		ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
217 		if (ed == NULL) {
218 			aprint_error_dev(self,
219 			    "could not read endpoint descriptor\n");
220 			sc->sc_dying = true;
221 			return;
222 		}
223 		addr = ed->bEndpointAddress;
224 		dir = UE_GET_DIR(ed->bEndpointAddress);
225 		attr = ed->bmAttributes & UE_XFERTYPE;
226 		if (dir == UE_DIR_IN && attr == UE_BULK) {
227 			ucaa.ucaa_bulkin = addr;
228 		} else if (dir == UE_DIR_OUT && attr == UE_BULK) {
229 			ucaa.ucaa_bulkout = addr;
230 		} else {
231 			aprint_error_dev(self, "unexpected endpoint\n");
232 		}
233 	}
234 	aprint_debug_dev(sc->sc_dev, "EPs: in=%#x out=%#x\n",
235 		ucaa.ucaa_bulkin, ucaa.ucaa_bulkout);
236 	if ((ucaa.ucaa_bulkin == -1) || (ucaa.ucaa_bulkout == -1)) {
237 		aprint_error_dev(self, "could not find endpoints\n");
238 		sc->sc_dying = true;
239 		return;
240 	}
241 
242 	sc->sc_subdev = config_found_sm_loc(self, "ucombus", NULL, &ucaa,
243 	                                    ucomprint, ucomsubmatch);
244 
245 	if (!pmf_device_register(self, NULL, NULL))
246 		aprint_error_dev(self, "couldn't establish power handler\n");
247 
248 	return;
249 }
250 
251 static int
252 uslsa_activate(device_t self, enum devact act)
253 {
254 	struct uslsa_softc *sc = device_private(self);
255 
256 	switch (act) {
257 	case DVACT_DEACTIVATE:
258 		sc->sc_dying = true;
259 		return 0;
260 	default:
261 		return EOPNOTSUPP;
262 	}
263 }
264 
265 static void
266 uslsa_childdet(device_t self, device_t child)
267 {
268 	struct uslsa_softc *sc = device_private(self);
269 
270 	KASSERT(sc->sc_subdev == child);
271 	sc->sc_subdev = NULL;
272 }
273 
274 static int
275 uslsa_detach(device_t self, int flags)
276 {
277 	struct uslsa_softc *sc = device_private(self);
278 	int rv = 0;
279 
280 	DPRINTF((self, "%s(%p, %#x)\n", __func__, self, flags));
281 
282 	sc->sc_dying = true;
283 
284 	if (sc->sc_subdev != NULL) {
285 		rv = config_detach(sc->sc_subdev, flags);
286 	}
287 
288 	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);
289 
290 	return (rv);
291 }
292 
293 static int
294 uslsa_usbd_errno(usbd_status status)
295 {
296 	switch (status) {
297 	case USBD_NORMAL_COMPLETION:
298 		return 0;
299 	case USBD_STALLED:
300 		return EINVAL;
301 	default:
302 		return EIO;
303 	}
304 }
305 
306 static void
307 uslsa_get_status(void *vsc, int portno, u_char *lsr, u_char *msr)
308 {
309 	struct uslsa_softc *sc;
310 	usb_device_request_t req;
311 	usbd_status status;
312 	uint8_t mdmsts;
313 
314 	sc = vsc;
315 
316 	DPRINTF((sc->sc_dev, "%s(%p, %d, ....)\n", __func__, vsc, portno));
317 
318 	if (sc->sc_dying) {
319 		return;
320 	}
321 
322 	req.bmRequestType = UT_READ_VENDOR_INTERFACE;
323 	req.bRequest = SLSA_R_GET_MDMSTS;
324 	USETW(req.wValue, 0);
325 	USETW(req.wIndex, sc->sc_ifnum);
326 	USETW(req.wLength, SLSA_RL_GET_MDMSTS);
327 
328 	status = usbd_do_request(sc->sc_udev, &req, &mdmsts);
329 	if (status != USBD_NORMAL_COMPLETION) {
330 		device_printf(sc->sc_dev, "%s: GET_MDMSTS %s\n",
331 		    __func__, usbd_errstr(status));
332 		return;
333 	}
334 
335 	DPRINTF((sc->sc_dev, "%s: GET_MDMSTS %#x\n", __func__, mdmsts));
336 
337 	if (lsr != NULL) {
338 		*lsr = 0;
339 	}
340 
341 	if (msr != NULL) {
342 		*msr = 0;
343 		*msr |= ISSET(mdmsts, SLSA_MDMSTS_CTS) ? UMSR_CTS : 0;
344 		*msr |= ISSET(mdmsts, SLSA_MDMSTS_DSR) ? UMSR_DSR : 0;
345 		*msr |= ISSET(mdmsts, SLSA_MDMSTS_RI) ? UMSR_RI : 0;
346 		*msr |= ISSET(mdmsts, SLSA_MDMSTS_DCD) ? UMSR_DCD : 0;
347 	}
348 }
349 
350 static void
351 uslsa_set(void *vsc, int portno, int reg, int onoff)
352 {
353 	struct uslsa_softc *sc;
354 
355 	sc = vsc;
356 
357 	DPRINTF((sc->sc_dev, "%s(%p, %d, %d, %d)\n", __func__, vsc, portno,
358 	    reg, onoff));
359 
360 	if (sc->sc_dying) {
361 		return;
362 	}
363 
364 	switch (reg) {
365 	case UCOM_SET_DTR:
366 		if (uslsa_request_set(sc, SLSA_R_SET_MHS,
367 		    SLSA_RV_SET_MHS_DTR_MASK |
368 		    (onoff ? SLSA_RV_SET_MHS_DTR : 0))) {
369 			device_printf(sc->sc_dev, "SET_MHS/DTR failed\n");
370 		}
371 		break;
372 	case UCOM_SET_RTS:
373 		if (uslsa_request_set(sc, SLSA_R_SET_MHS,
374 		    SLSA_RV_SET_MHS_RTS_MASK |
375 		    (onoff ? SLSA_RV_SET_MHS_RTS : 0))) {
376 			device_printf(sc->sc_dev, "SET_MHS/RTS failed\n");
377 		}
378 		break;
379 	case UCOM_SET_BREAK:
380 		if (uslsa_request_set(sc, SLSA_R_SET_BREAK,
381 		    (onoff ? SLSA_RV_SET_BREAK_ENABLE :
382 		     SLSA_RV_SET_BREAK_DISABLE))) {
383 			device_printf(sc->sc_dev, "SET_BREAK failed\n");
384 		}
385 		break;
386 	default:
387 		break;
388 	}
389 }
390 
391 static int
392 uslsa_param(void *vsc, int portno, struct termios *t)
393 {
394 	struct uslsa_softc *sc;
395 	usb_device_request_t req;
396 	usbd_status status;
397 	uint16_t value;
398 	uint32_t baud;
399 	int ret;
400 
401 	sc = vsc;
402 
403 	DPRINTF((sc->sc_dev, "%s(%p, %d, %p)\n", __func__, vsc, portno, t));
404 
405 	if (sc->sc_dying) {
406 		return EIO;
407 	}
408 
409 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
410 	req.bRequest = SLSA_R_SET_BAUDRATE;
411 	USETW(req.wValue, 0);
412 	USETW(req.wIndex, sc->sc_ifnum);
413 	USETW(req.wLength, 4);
414 
415 	baud = t->c_ospeed;
416 	status = usbd_do_request(sc->sc_udev, &req, &baud);
417 	if (status != USBD_NORMAL_COMPLETION) {
418 		/* fallback method for devices that don't know SET_BAUDRATE */
419 		/* hope we calculate it right */
420 		device_printf(sc->sc_dev, "%s: set baudrate %d, failed %s,"
421 				" using set bauddiv\n",
422 		    __func__, baud, usbd_errstr(status));
423 
424 		value = SLSA_RV_BAUDDIV(t->c_ospeed);
425 		if ((ret = uslsa_request_set(sc, SLSA_R_SET_BAUDDIV, value))
426 		    != 0) {
427 			device_printf(sc->sc_dev, "%s: SET_BAUDDIV failed\n",
428 			       __func__);
429 			return ret;
430 		}
431 	}
432 
433 	value = 0;
434 
435 	if (ISSET(t->c_cflag, CSTOPB)) {
436 		value |= SLSA_RV_LINE_CTL_STOP_2;
437 	} else {
438 		value |= SLSA_RV_LINE_CTL_STOP_1;
439 	}
440 
441 	if (ISSET(t->c_cflag, PARENB)) {
442 		if (ISSET(t->c_cflag, PARODD)) {
443 			value |= SLSA_RV_LINE_CTL_PARITY_ODD;
444 		} else {
445 			value |= SLSA_RV_LINE_CTL_PARITY_EVEN;
446 		}
447 	} else {
448 		value |= SLSA_RV_LINE_CTL_PARITY_NONE;
449 	}
450 
451 	switch (ISSET(t->c_cflag, CSIZE)) {
452 	case CS5:
453 		value |= SLSA_RV_LINE_CTL_LEN_5;
454 		break;
455 	case CS6:
456 		value |= SLSA_RV_LINE_CTL_LEN_6;
457 		break;
458 	case CS7:
459 		value |= SLSA_RV_LINE_CTL_LEN_7;
460 		break;
461 	case CS8:
462 		value |= SLSA_RV_LINE_CTL_LEN_8;
463 		break;
464 	}
465 
466 	DPRINTF((sc->sc_dev, "%s: setting LINE_CTL to 0x%x\n",
467 	    __func__, value));
468 	if ((ret = uslsa_request_set(sc, SLSA_R_SET_LINE_CTL, value)) != 0) {
469 		device_printf(sc->sc_dev, "SET_LINE_CTL failed\n");
470 		return ret;
471 	}
472 
473 	if ((ret = uslsa_set_flow(sc, t->c_cflag, t->c_iflag)) != 0) {
474 		device_printf(sc->sc_dev, "SET_LINE_CTL failed\n");
475 	}
476 
477 	return ret;
478 }
479 
480 static int
481 uslsa_ioctl(void *vsc, int portno, u_long cmd, void *data, int flag, proc_t *p)
482 {
483 	struct uslsa_softc *sc;
484 
485 	sc = vsc;
486 
487 	switch (cmd) {
488 	case TIOCMGET:
489 		ucom_status_change(device_private(sc->sc_subdev));
490 		return EPASSTHROUGH;
491 	default:
492 		return EPASSTHROUGH;
493 	}
494 
495 	return 0;
496 }
497 
498 static int
499 uslsa_open(void *vsc, int portno)
500 {
501 	struct uslsa_softc *sc;
502 
503 	sc = vsc;
504 
505 	DPRINTF((sc->sc_dev, "%s(%p, %d)\n", __func__, vsc, portno));
506 
507 	if (sc->sc_dying) {
508 		return EIO;
509 	}
510 
511 	return uslsa_request_set(sc, SLSA_R_IFC_ENABLE,
512 	    SLSA_RV_IFC_ENABLE_ENABLE);
513 }
514 
515 static void
516 uslsa_close(void *vsc, int portno)
517 {
518 	struct uslsa_softc *sc;
519 
520 	sc = vsc;
521 
522 	DPRINTF((sc->sc_dev, "%s(%p, %d)\n", __func__, vsc, portno));
523 
524 	if (sc->sc_dying) {
525 		return;
526 	}
527 
528 	(void)uslsa_request_set(sc, SLSA_R_IFC_ENABLE,
529 	    SLSA_RV_IFC_ENABLE_DISABLE);
530 }
531 
532 static int
533 uslsa_request_set(struct uslsa_softc * sc, uint8_t request, uint16_t value)
534 {
535 	usb_device_request_t req;
536 	usbd_status status;
537 
538 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
539 	req.bRequest = request;
540 	USETW(req.wValue, value);
541 	USETW(req.wIndex, sc->sc_ifnum);
542 	USETW(req.wLength, 0);
543 
544 	status = usbd_do_request(sc->sc_udev, &req, NULL);
545 
546 	return uslsa_usbd_errno(status);
547 }
548 
549 static int
550 uslsa_set_flow(struct uslsa_softc *sc, tcflag_t cflag, tcflag_t iflag)
551 {
552 	struct slsa_fcs fcs;
553 	usb_device_request_t req;
554 	uint32_t ulControlHandshake;
555 	uint32_t ulFlowReplace;
556 	usbd_status status;
557 
558 	DPRINTF((sc->sc_dev, "%s(%p, %#x, %#x)\n", __func__, sc, cflag, iflag));
559 
560 	req.bmRequestType = UT_READ_VENDOR_INTERFACE;
561 	req.bRequest = SLSA_R_GET_FLOW;
562 	USETW(req.wValue, 0);
563 	USETW(req.wIndex, sc->sc_ifnum);
564 	USETW(req.wLength, SLSA_RL_GET_FLOW);
565 
566 	status = usbd_do_request(sc->sc_udev, &req, &fcs);
567 	if (status != USBD_NORMAL_COMPLETION) {
568 		device_printf(sc->sc_dev, "%s: GET_FLOW %s\n",
569 			__func__, usbd_errstr(status));
570 		return uslsa_usbd_errno(status);
571 	}
572 
573 	ulControlHandshake = le32toh(fcs.ulControlHandshake);
574 	ulFlowReplace = le32toh(fcs.ulFlowReplace);
575 
576 	if (ISSET(cflag, CRTSCTS)) {
577 		ulControlHandshake =
578 		    SERIAL_CTS_HANDSHAKE | __SHIFTIN(1, SERIAL_DTR_MASK);
579 		ulFlowReplace = __SHIFTIN(2, SERIAL_RTS_MASK);
580 	} else {
581 		ulControlHandshake = __SHIFTIN(1, SERIAL_DTR_MASK);
582 		ulFlowReplace = __SHIFTIN(1, SERIAL_RTS_MASK);
583 	}
584 
585 	fcs.ulControlHandshake = htole32(ulControlHandshake);
586 	fcs.ulFlowReplace = htole32(ulFlowReplace);
587 
588 	req.bmRequestType = UT_WRITE_VENDOR_INTERFACE;
589 	req.bRequest = SLSA_R_SET_FLOW;
590 	USETW(req.wValue, 0);
591 	USETW(req.wIndex, sc->sc_ifnum);
592 	USETW(req.wLength, SLSA_RL_SET_FLOW);
593 
594 	status = usbd_do_request(sc->sc_udev, &req, &fcs);
595 
596 	return uslsa_usbd_errno(status);
597 }
598