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      1 /* $NetBSD: uslsa.c,v 1.33 2025/02/16 18:30:28 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 (at) 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 1.33 2025/02/16 18:30:28 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 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_CP210X_3 },
    142         { USB_VENDOR_SILABS,            USB_PRODUCT_SILABS_SUNNTO },
    143         { USB_VENDOR_SILABS2,           USB_PRODUCT_SILABS2_DCU11CLONE },
    144         { USB_VENDOR_USI,               USB_PRODUCT_USI_MC60 },
    145 	{ USB_VENDOR_WMR,		USB_PRODUCT_WMR_RIGBLASTER },
    146 };
    147 
    148 static int uslsa_match(device_t, cfdata_t, void *);
    149 static void uslsa_attach(device_t, device_t, void *);
    150 static void uslsa_childdet(device_t, device_t);
    151 static int uslsa_detach(device_t, int);
    152 
    153 CFATTACH_DECL2_NEW(uslsa, sizeof(struct uslsa_softc), uslsa_match,
    154     uslsa_attach, uslsa_detach, NULL, NULL, uslsa_childdet);
    155 
    156 static int
    157 uslsa_match(device_t parent, cfdata_t match, void *aux)
    158 {
    159 	const struct usbif_attach_arg *uiaa = aux;
    160 
    161 	if (usb_lookup(uslsa_devs, uiaa->uiaa_vendor, uiaa->uiaa_product)
    162 	    != NULL)
    163 		return UMATCH_VENDOR_PRODUCT;
    164 	else
    165 		return UMATCH_NONE;
    166 }
    167 
    168 static void
    169 uslsa_attach(device_t parent, device_t self, void *aux)
    170 {
    171 	struct uslsa_softc *sc;
    172 	const struct usbif_attach_arg *uiaa = aux;
    173 	const usb_interface_descriptor_t *id;
    174 	const usb_endpoint_descriptor_t *ed;
    175 	char *devinfop;
    176 	struct ucom_attach_args ucaa;
    177 	int i;
    178 
    179 	sc = device_private(self);
    180 
    181 	sc->sc_dev = self;
    182 	sc->sc_udev = uiaa->uiaa_device;
    183 	sc->sc_iface = uiaa->uiaa_iface;
    184 	sc->sc_dying = false;
    185 
    186 	aprint_naive("\n");
    187 	aprint_normal("\n");
    188 
    189 	devinfop = usbd_devinfo_alloc(sc->sc_udev, 0);
    190 	aprint_normal_dev(self, "%s\n", devinfop);
    191 	usbd_devinfo_free(devinfop);
    192 
    193 	id = usbd_get_interface_descriptor(sc->sc_iface);
    194 
    195 	sc->sc_ifnum = id->bInterfaceNumber;
    196 
    197 	ucaa.ucaa_info = "Silicon Labs CP210x";
    198 	ucaa.ucaa_portno = UCOM_UNK_PORTNO;
    199 	ucaa.ucaa_ibufsize = USLSA_BUFSIZE;
    200 	ucaa.ucaa_obufsize = USLSA_BUFSIZE;
    201 	ucaa.ucaa_ibufsizepad = USLSA_BUFSIZE;
    202 	ucaa.ucaa_opkthdrlen = 0;
    203 	ucaa.ucaa_device = sc->sc_udev;
    204 	ucaa.ucaa_iface = sc->sc_iface;
    205 	ucaa.ucaa_methods = &uslsa_methods;
    206 	ucaa.ucaa_arg = sc;
    207 
    208 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
    209 
    210 	ucaa.ucaa_bulkin = ucaa.ucaa_bulkout = -1;
    211 	for (i = 0; i < id->bNumEndpoints; i++) {
    212 		int addr, dir, attr;
    213 
    214 		ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
    215 		if (ed == NULL) {
    216 			aprint_error_dev(self,
    217 			    "could not read endpoint descriptor\n");
    218 			sc->sc_dying = true;
    219 			return;
    220 		}
    221 		addr = ed->bEndpointAddress;
    222 		dir = UE_GET_DIR(ed->bEndpointAddress);
    223 		attr = ed->bmAttributes & UE_XFERTYPE;
    224 		if (dir == UE_DIR_IN && attr == UE_BULK) {
    225 			ucaa.ucaa_bulkin = addr;
    226 		} else if (dir == UE_DIR_OUT && attr == UE_BULK) {
    227 			ucaa.ucaa_bulkout = addr;
    228 		} else {
    229 			aprint_error_dev(self, "unexpected endpoint\n");
    230 		}
    231 	}
    232 	aprint_debug_dev(sc->sc_dev, "EPs: in=%#x out=%#x\n",
    233 		ucaa.ucaa_bulkin, ucaa.ucaa_bulkout);
    234 	if ((ucaa.ucaa_bulkin == -1) || (ucaa.ucaa_bulkout == -1)) {
    235 		aprint_error_dev(self, "could not find endpoints\n");
    236 		sc->sc_dying = true;
    237 		return;
    238 	}
    239 
    240 	sc->sc_subdev = config_found(self, &ucaa, ucomprint,
    241 	    CFARGS(.submatch = ucomsubmatch));
    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 = htole32(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