xref: /netbsd-src/sys/dev/usb/uftdi.c (revision 70f7362772ba52b749c976fb5e86e39a8b2c9afc)
1 /*	$NetBSD: uftdi.c,v 1.77 2024/03/26 03:38:02 thorpej 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: uftdi.c,v 1.77 2024/03/26 03:38:02 thorpej Exp $");
34 
35 #ifdef _KERNEL_OPT
36 #include "opt_usb.h"
37 #endif
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/device.h>
43 #include <sys/conf.h>
44 #include <sys/tty.h>
45 
46 #include <dev/usb/usb.h>
47 
48 #include <dev/usb/usbdi.h>
49 #include <dev/usb/usbdi_util.h>
50 #include <dev/usb/usbdivar.h>
51 #include <dev/usb/usbdevs.h>
52 
53 #include <dev/usb/ucomvar.h>
54 
55 #include <dev/usb/uftdireg.h>
56 
57 #ifdef UFTDI_DEBUG
58 #define DPRINTF(x)	if (uftdidebug) printf x
59 #define DPRINTFN(n,x)	if (uftdidebug>(n)) printf x
60 int uftdidebug = 0;
61 #else
62 #define DPRINTF(x)
63 #define DPRINTFN(n,x)
64 #endif
65 
66 #define UFTDI_CONFIG_NO		1
67 
68 /*
69  * These are the default number of bytes transferred per frame if the
70  * endpoint doesn't tell us.  The output buffer size is a hard limit
71  * for devices that use a 6-bit size encoding.
72  */
73 #define UFTDIIBUFSIZE 64
74 #define UFTDIOBUFSIZE 64
75 
76 /*
77  * Magic constants!  Where do these come from?  They're what Linux uses...
78  */
79 #define	UFTDI_MAX_IBUFSIZE	512
80 #define	UFTDI_MAX_OBUFSIZE	256
81 
82 struct uftdi_softc {
83 	device_t		sc_dev;		/* base device */
84 	struct usbd_device *	sc_udev;	/* device */
85 	struct usbd_interface *	sc_iface;	/* interface */
86 	int			sc_iface_no;
87 
88 	enum uftdi_type		sc_type;
89 	u_int			sc_flags;
90 #define FLAGS_BAUDCLK_12M	0x00000001
91 #define FLAGS_ROUNDOFF_232A	0x00000002
92 #define FLAGS_BAUDBITS_HINDEX	0x00000004
93 	u_int			sc_hdrlen;
94 	u_int			sc_chiptype;
95 
96 	u_char			sc_msr;
97 	u_char			sc_lsr;
98 
99 	device_t		sc_subdev;
100 
101 	bool			sc_dying;
102 
103 	u_int			last_lcr;
104 };
105 
106 static void	uftdi_get_status(void *, int, u_char *, u_char *);
107 static void	uftdi_set(void *, int, int, int);
108 static int	uftdi_param(void *, int, struct termios *);
109 static int	uftdi_open(void *, int);
110 static void	uftdi_read(void *, int, u_char **, uint32_t *);
111 static void	uftdi_write(void *, int, u_char *, u_char *, uint32_t *);
112 static void	uftdi_break(void *, int, int);
113 
114 static const struct ucom_methods uftdi_methods = {
115 	.ucom_get_status = uftdi_get_status,
116 	.ucom_set = uftdi_set,
117 	.ucom_param = uftdi_param,
118 	.ucom_open = uftdi_open,
119 	.ucom_read = uftdi_read,
120 	.ucom_write = uftdi_write,
121 };
122 
123 /*
124  * The devices default to UFTDI_TYPE_8U232AM.
125  * Remember to update uftdi_attach() if it should be UFTDI_TYPE_SIO instead
126  */
127 static const struct usb_devno uftdi_devs[] = {
128 	{ USB_VENDOR_BBELECTRONICS, USB_PRODUCT_BBELECTRONICS_USOTL4 },
129 	{ USB_VENDOR_FALCOM, USB_PRODUCT_FALCOM_TWIST },
130 	{ USB_VENDOR_FALCOM, USB_PRODUCT_FALCOM_SAMBA },
131 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_230X },
132 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_232H },
133 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_232RL },
134 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_2232C },
135 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_4232H },
136 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_8U100AX },
137 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SERIAL_8U232AM },
138 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_KW },
139 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_YS },
140 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_Y6 },
141 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_Y8 },
142 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_IC },
143 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_DB9 },
144 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_RS232 },
145 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MHAM_Y9 },
146 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_COASTAL_TNCX },
147 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_CTI_485_MINI },
148 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_CTI_NANO_485 },
149 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_SEMC_DSS20 },
150 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_LK202_24_USB },
151 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_LK204_24_USB },
152 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_MX200_USB },
153 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_MX4_MX5_USB },
154 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_CFA_631 },
155 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_CFA_632 },
156 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_CFA_633 },
157 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_CFA_634 },
158 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_LCD_CFA_635 },
159 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_OPENRD_JTAGKEY },
160 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_BEAGLEBONE },
161 	{ USB_VENDOR_FTDI, USB_PRODUCT_FTDI_MAXSTREAM_PKG_U },
162 	{ USB_VENDOR_xxFTDI, USB_PRODUCT_xxFTDI_SHEEVAPLUG_JTAG },
163 	{ USB_VENDOR_INTREPIDCS, USB_PRODUCT_INTREPIDCS_VALUECAN },
164 	{ USB_VENDOR_INTREPIDCS, USB_PRODUCT_INTREPIDCS_NEOVI },
165 	{ USB_VENDOR_MELCO, USB_PRODUCT_MELCO_PCOPRS1 },
166 	{ USB_VENDOR_RATOC, USB_PRODUCT_RATOC_REXUSB60F },
167 	{ USB_VENDOR_RTSYS, USB_PRODUCT_RTSYS_CT57A },
168 	{ USB_VENDOR_RTSYS, USB_PRODUCT_RTSYS_RTS03 },
169 	{ USB_VENDOR_SEALEVEL, USB_PRODUCT_SEALEVEL_USBSERIAL },
170 	{ USB_VENDOR_SEALEVEL, USB_PRODUCT_SEALEVEL_SEAPORT4P1 },
171 	{ USB_VENDOR_SEALEVEL, USB_PRODUCT_SEALEVEL_SEAPORT4P2 },
172 	{ USB_VENDOR_SEALEVEL, USB_PRODUCT_SEALEVEL_SEAPORT4P3 },
173 	{ USB_VENDOR_SEALEVEL, USB_PRODUCT_SEALEVEL_SEAPORT4P4 },
174 	{ USB_VENDOR_SIIG2, USB_PRODUCT_SIIG2_US2308 },
175 	{ USB_VENDOR_MISC, USB_PRODUCT_MISC_TELLSTICK },
176 	{ USB_VENDOR_MISC, USB_PRODUCT_MISC_TELLSTICK_DUO },
177 };
178 #define uftdi_lookup(v, p) usb_lookup(uftdi_devs, v, p)
179 
180 static int	uftdi_match(device_t, cfdata_t, void *);
181 static void	uftdi_attach(device_t, device_t, void *);
182 static void	uftdi_childdet(device_t, device_t);
183 static int	uftdi_detach(device_t, int);
184 
185 CFATTACH_DECL2_NEW(uftdi, sizeof(struct uftdi_softc), uftdi_match,
186     uftdi_attach, uftdi_detach, NULL, NULL, uftdi_childdet);
187 
188 struct uftdi_match_quirk_entry {
189 	uint16_t	vendor_id;
190 	uint16_t	product_id;
191 	int		iface_no;
192 	const char *	vendor_str;
193 	const char *	product_str;
194 	int		match_ret;
195 };
196 
197 static const struct uftdi_match_quirk_entry uftdi_match_quirks[] = {
198 	/*
199 	 * The Tigard board (https://github.com/tigard-tools/tigard)
200 	 * has two interfaces, one of which is meant to act as a
201 	 * regular USB serial port (interface 0), the other of which
202 	 * is meant for other protocols (SWD, JTAG, etc.).  We must
203 	 * reject interface 1 so that ugenif matches, thus allowing
204 	 * full user-space control of that port.
205 	 */
206 	{
207 	  .vendor_id	= USB_VENDOR_FTDI,
208 	  .product_id	= USB_PRODUCT_FTDI_SERIAL_2232C,
209 	  .iface_no	= 1,
210 	  .vendor_str	= "SecuringHardware.com",
211 	  .product_str	= "Tigard V1.1",
212 	  .match_ret	= UMATCH_NONE,
213 	}
214 };
215 
216 static int
217 uftdi_quirk_match(struct usbif_attach_arg *uiaa, int rv)
218 {
219 	struct usbd_device *dev = uiaa->uiaa_device;
220 	const struct uftdi_match_quirk_entry *q;
221 	int i;
222 
223 	for (i = 0; i < __arraycount(uftdi_match_quirks); i++) {
224 		q = &uftdi_match_quirks[i];
225 		if (uiaa->uiaa_vendor != q->vendor_id ||
226 		    uiaa->uiaa_product != q->product_id ||
227 		    uiaa->uiaa_ifaceno != q->iface_no) {
228 			continue;
229 		}
230 		if (q->vendor_str != NULL &&
231 		    (dev->ud_vendor == NULL ||
232 		     strcmp(dev->ud_vendor, q->vendor_str) != 0)) {
233 			continue;
234 		}
235 		if (q->product_str != NULL &&
236 		    (dev->ud_product == NULL ||
237 		     strcmp(dev->ud_product, q->product_str) != 0)) {
238 			continue;
239 		}
240 		/*
241 		 * Got a match!
242 		 */
243 		rv = q->match_ret;
244 		break;
245 	}
246 	return rv;
247 }
248 
249 static int
250 uftdi_match(device_t parent, cfdata_t match, void *aux)
251 {
252 	struct usbif_attach_arg *uiaa = aux;
253 	int rv;
254 
255 	DPRINTFN(20,("uftdi: vendor=%#x, product=%#x\n",
256 		     uiaa->uiaa_vendor, uiaa->uiaa_product));
257 
258 	if (uiaa->uiaa_configno != UFTDI_CONFIG_NO)
259 		return UMATCH_NONE;
260 
261 	rv = uftdi_lookup(uiaa->uiaa_vendor, uiaa->uiaa_product) != NULL ?
262 		UMATCH_VENDOR_PRODUCT_CONF_IFACE : UMATCH_NONE;
263 	if (rv != UMATCH_NONE) {
264 		rv = uftdi_quirk_match(uiaa, rv);
265 	}
266 	return rv;
267 }
268 
269 static void
270 uftdi_attach(device_t parent, device_t self, void *aux)
271 {
272 	struct uftdi_softc *sc = device_private(self);
273 	struct usbif_attach_arg *uiaa = aux;
274 	struct usbd_device *dev = uiaa->uiaa_device;
275 	struct usbd_interface *iface = uiaa->uiaa_iface;
276 	usb_device_descriptor_t *ddesc;
277 	usb_interface_descriptor_t *id;
278 	usb_endpoint_descriptor_t *ed;
279 	char *devinfop;
280 	int i;
281 	struct ucom_attach_args ucaa;
282 
283 	DPRINTFN(10,("\nuftdi_attach: sc=%p\n", sc));
284 
285 	aprint_naive("\n");
286 	aprint_normal("\n");
287 
288 	devinfop = usbd_devinfo_alloc(dev, 0);
289 	aprint_normal_dev(self, "%s\n", devinfop);
290 	usbd_devinfo_free(devinfop);
291 
292 	sc->sc_dev = self;
293 	sc->sc_udev = dev;
294 	sc->sc_dying = false;
295 	sc->sc_iface_no = uiaa->uiaa_ifaceno;
296 	sc->sc_type = UFTDI_TYPE_8U232AM; /* most devices are post-8U232AM */
297 	sc->sc_hdrlen = 0;
298 
299 	ddesc = usbd_get_device_descriptor(dev);
300 	sc->sc_chiptype = UGETW(ddesc->bcdDevice);
301 
302 	switch (sc->sc_chiptype) {
303 	case 0x0200:
304 		if (ddesc->iSerialNumber != 0)
305 			sc->sc_flags |= FLAGS_ROUNDOFF_232A;
306 		ucaa.ucaa_portno = 0;
307 		break;
308 	case 0x0400:
309 		ucaa.ucaa_portno = 0;
310 		break;
311 	case 0x0500:
312 		sc->sc_flags |= FLAGS_BAUDBITS_HINDEX;
313 		ucaa.ucaa_portno = FTDI_PIT_SIOA + sc->sc_iface_no;
314 		break;
315 	case 0x0600:
316 		ucaa.ucaa_portno = 0;
317 		break;
318 	case 0x0700:
319 	case 0x0800:
320 	case 0x0900:
321 		sc->sc_flags |= FLAGS_BAUDCLK_12M;
322 		sc->sc_flags |= FLAGS_BAUDBITS_HINDEX;
323 		ucaa.ucaa_portno = FTDI_PIT_SIOA + sc->sc_iface_no;
324 		break;
325 	case 0x1000:
326 		sc->sc_flags |= FLAGS_BAUDBITS_HINDEX;
327 		ucaa.ucaa_portno = FTDI_PIT_SIOA + sc->sc_iface_no;
328 		break;
329 	default:
330 		if (sc->sc_chiptype < 0x0200) {
331 			sc->sc_type = UFTDI_TYPE_SIO;
332 			sc->sc_hdrlen = 1;
333 		}
334 		ucaa.ucaa_portno = 0;
335 		break;
336 	}
337 
338 	id = usbd_get_interface_descriptor(iface);
339 
340 	sc->sc_iface = iface;
341 
342 	ucaa.ucaa_bulkin = ucaa.ucaa_bulkout = -1;
343 	ucaa.ucaa_ibufsize = ucaa.ucaa_obufsize = 0;
344 	for (i = 0; i < id->bNumEndpoints; i++) {
345 		int addr, dir, attr;
346 		ed = usbd_interface2endpoint_descriptor(iface, i);
347 		if (ed == NULL) {
348 			aprint_error_dev(self,
349 			    "could not read endpoint descriptor\n");
350 			goto bad;
351 		}
352 
353 		addr = ed->bEndpointAddress;
354 		dir = UE_GET_DIR(ed->bEndpointAddress);
355 		attr = ed->bmAttributes & UE_XFERTYPE;
356 		if (dir == UE_DIR_IN && attr == UE_BULK) {
357 			ucaa.ucaa_bulkin = addr;
358 			ucaa.ucaa_ibufsize = UGETW(ed->wMaxPacketSize);
359 			if (ucaa.ucaa_ibufsize >= UFTDI_MAX_IBUFSIZE)
360 				ucaa.ucaa_ibufsize = UFTDI_MAX_IBUFSIZE;
361 		} else if (dir == UE_DIR_OUT && attr == UE_BULK) {
362 			ucaa.ucaa_bulkout = addr;
363 			ucaa.ucaa_obufsize = UGETW(ed->wMaxPacketSize)
364 			    - sc->sc_hdrlen;
365 			if (ucaa.ucaa_obufsize >= UFTDI_MAX_OBUFSIZE)
366 				ucaa.ucaa_obufsize = UFTDI_MAX_OBUFSIZE;
367 			/* Limit length if we have a 6-bit header.  */
368 			if ((sc->sc_hdrlen > 0) &&
369 			    (ucaa.ucaa_obufsize > UFTDIOBUFSIZE))
370 				ucaa.ucaa_obufsize = UFTDIOBUFSIZE;
371 		} else {
372 			aprint_error_dev(self, "unexpected endpoint\n");
373 			goto bad;
374 		}
375 	}
376 	if (ucaa.ucaa_bulkin == -1) {
377 		aprint_error_dev(self, "Could not find data bulk in\n");
378 		goto bad;
379 	}
380 	if (ucaa.ucaa_bulkout == -1) {
381 		aprint_error_dev(self, "Could not find data bulk out\n");
382 		goto bad;
383 	}
384 
385 	/* ucaa_bulkin, ucaa_bulkout set above */
386 	if (ucaa.ucaa_ibufsize == 0)
387 		ucaa.ucaa_ibufsize = UFTDIIBUFSIZE;
388 	ucaa.ucaa_ibufsizepad = ucaa.ucaa_ibufsize;
389 	if (ucaa.ucaa_obufsize == 0)
390 		ucaa.ucaa_obufsize = UFTDIOBUFSIZE - sc->sc_hdrlen;
391 	ucaa.ucaa_opkthdrlen = sc->sc_hdrlen;
392 	ucaa.ucaa_device = dev;
393 	ucaa.ucaa_iface = iface;
394 	ucaa.ucaa_methods = &uftdi_methods;
395 	ucaa.ucaa_arg = sc;
396 	ucaa.ucaa_info = NULL;
397 
398 	DPRINTF(("uftdi: in=%#x out=%#x isize=%#x osize=%#x\n",
399 		ucaa.ucaa_bulkin, ucaa.ucaa_bulkout,
400 		ucaa.ucaa_ibufsize, ucaa.ucaa_obufsize));
401 	sc->sc_subdev = config_found(self, &ucaa, ucomprint,
402 	    CFARGS(.submatch = ucomsubmatch));
403 
404 	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);
405 
406 	if (!pmf_device_register(self, NULL, NULL))
407 		aprint_error_dev(self, "couldn't establish power handler\n");
408 
409 	return;
410 
411 bad:
412 	DPRINTF(("uftdi_attach: ATTACH ERROR\n"));
413 	sc->sc_dying = true;
414 	return;
415 }
416 
417 static void
418 uftdi_childdet(device_t self, device_t child)
419 {
420 	struct uftdi_softc *sc = device_private(self);
421 
422 	KASSERT(child == sc->sc_subdev);
423 	sc->sc_subdev = NULL;
424 }
425 
426 static int
427 uftdi_detach(device_t self, int flags)
428 {
429 	struct uftdi_softc *sc = device_private(self);
430 	int rv = 0;
431 
432 	DPRINTF(("uftdi_detach: sc=%p flags=%d\n", sc, flags));
433 
434 	sc->sc_dying = true;
435 
436 	if (sc->sc_subdev != NULL) {
437 		rv = config_detach(sc->sc_subdev, flags);
438 		sc->sc_subdev = NULL;
439 	}
440 
441 	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);
442 
443 	return rv;
444 }
445 
446 static int
447 uftdi_open(void *vsc, int portno)
448 {
449 	struct uftdi_softc *sc = vsc;
450 	usb_device_request_t req;
451 	usbd_status err;
452 	struct termios t;
453 
454 	DPRINTF(("uftdi_open: sc=%p\n", sc));
455 
456 	if (sc->sc_dying)
457 		return EIO;
458 
459 	/* Perform a full reset on the device */
460 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
461 	req.bRequest = FTDI_SIO_RESET;
462 	USETW(req.wValue, FTDI_SIO_RESET_SIO);
463 	USETW(req.wIndex, portno);
464 	USETW(req.wLength, 0);
465 	err = usbd_do_request(sc->sc_udev, &req, NULL);
466 	if (err)
467 		return EIO;
468 
469 	/* Set 9600 baud, 2 stop bits, no parity, 8 bits */
470 	t.c_ospeed = 9600;
471 	t.c_cflag = CSTOPB | CS8;
472 	(void)uftdi_param(sc, portno, &t);
473 
474 	/* Turn on RTS/CTS flow control */
475 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
476 	req.bRequest = FTDI_SIO_SET_FLOW_CTRL;
477 	USETW(req.wValue, 0);
478 	USETW2(req.wIndex, FTDI_SIO_RTS_CTS_HS, portno);
479 	USETW(req.wLength, 0);
480 	err = usbd_do_request(sc->sc_udev, &req, NULL);
481 	if (err)
482 		return EIO;
483 
484 	return 0;
485 }
486 
487 static void
488 uftdi_read(void *vsc, int portno, u_char **ptr, uint32_t *count)
489 {
490 	struct uftdi_softc *sc = vsc;
491 	u_char msr, lsr;
492 
493 	DPRINTFN(15,("uftdi_read: sc=%p, port=%d count=%d\n", sc, portno,
494 		     *count));
495 
496 	msr = FTDI_GET_MSR(*ptr);
497 	lsr = FTDI_GET_LSR(*ptr);
498 
499 #ifdef UFTDI_DEBUG
500 	if (*count != 2)
501 		DPRINTFN(10,("uftdi_read: sc=%p, port=%d count=%d data[0]="
502 			    "0x%02x\n", sc, portno, *count, (*ptr)[2]));
503 #endif
504 
505 	if (sc->sc_msr != msr ||
506 	    (sc->sc_lsr & FTDI_LSR_MASK) != (lsr & FTDI_LSR_MASK)) {
507 		DPRINTF(("uftdi_read: status change msr=0x%02x(0x%02x) "
508 			 "lsr=0x%02x(0x%02x)\n", msr, sc->sc_msr,
509 			 lsr, sc->sc_lsr));
510 		sc->sc_msr = msr;
511 		sc->sc_lsr = lsr;
512 		ucom_status_change(device_private(sc->sc_subdev));
513 	}
514 
515 	/* Adjust buffer pointer to skip status prefix */
516 	*ptr += 2;
517 }
518 
519 static void
520 uftdi_write(void *vsc, int portno, u_char *to, u_char *from, uint32_t *count)
521 {
522 	struct uftdi_softc *sc = vsc;
523 
524 	DPRINTFN(10,("uftdi_write: sc=%p, port=%d count=%u data[0]=0x%02x\n",
525 		     vsc, portno, *count, from[0]));
526 
527 	/* Make length tag and copy data */
528 	if (sc->sc_hdrlen > 0)
529 		*to = FTDI_OUT_TAG(*count, portno);
530 
531 	memcpy(to + sc->sc_hdrlen, from, *count);
532 	*count += sc->sc_hdrlen;
533 }
534 
535 static void
536 uftdi_set(void *vsc, int portno, int reg, int onoff)
537 {
538 	struct uftdi_softc *sc = vsc;
539 	usb_device_request_t req;
540 	int ctl;
541 
542 	DPRINTF(("uftdi_set: sc=%p, port=%d reg=%d onoff=%d\n", vsc, portno,
543 		 reg, onoff));
544 
545 	if (sc->sc_dying)
546 		return;
547 
548 	switch (reg) {
549 	case UCOM_SET_DTR:
550 		ctl = onoff ? FTDI_SIO_SET_DTR_HIGH : FTDI_SIO_SET_DTR_LOW;
551 		break;
552 	case UCOM_SET_RTS:
553 		ctl = onoff ? FTDI_SIO_SET_RTS_HIGH : FTDI_SIO_SET_RTS_LOW;
554 		break;
555 	case UCOM_SET_BREAK:
556 		uftdi_break(sc, portno, onoff);
557 		return;
558 	default:
559 		return;
560 	}
561 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
562 	req.bRequest = FTDI_SIO_MODEM_CTRL;
563 	USETW(req.wValue, ctl);
564 	USETW(req.wIndex, portno);
565 	USETW(req.wLength, 0);
566 	DPRINTFN(2,("uftdi_set: reqtype=0x%02x req=0x%02x value=0x%04x "
567 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
568 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
569 	(void)usbd_do_request(sc->sc_udev, &req, NULL);
570 }
571 
572 /*
573  * Return true if the given speed is within operational tolerance of the target
574  * speed.  FTDI recommends that the hardware speed be within 3% of nominal.
575  */
576 static inline bool
577 uftdi_baud_within_tolerance(uint64_t speed, uint64_t target)
578 {
579 	return ((speed >= (target * 100) / 103) &&
580 	    (speed <= (target * 100) / 97));
581 }
582 
583 static int
584 uftdi_encode_baudrate(struct uftdi_softc *sc, int speed, int *rate, int *ratehi)
585 {
586 	static const uint8_t encoded_fraction[8] = {
587 	    0, 3, 2, 4, 1, 5, 6, 7
588 	};
589 	static const uint8_t roundoff_232a[16] = {
590 	    0,  1,  0,  1,  0, -1,  2,  1,
591 	    0, -1, -2, -3,  4,  3,  2,  1,
592 	};
593 	uint32_t clk, divisor, fastclk_flag, frac, hwspeed;
594 
595 	/*
596 	 * If this chip has the fast clock capability and the speed is within
597 	 * range, use the 12MHz clock, otherwise the standard clock is 3MHz.
598 	 */
599 	if ((sc->sc_flags & FLAGS_BAUDCLK_12M) && speed >= 1200) {
600 		clk = 12000000;
601 		fastclk_flag = (1 << 17);
602 	} else {
603 		clk = 3000000;
604 		fastclk_flag = 0;
605 	}
606 
607 	/*
608 	 * Make sure the requested speed is reachable with the available clock
609 	 * and a 14-bit divisor.
610 	 */
611 	if (speed < (clk >> 14) || speed > clk)
612 		return -1;
613 
614 	/*
615 	 * Calculate the divisor, initially yielding a fixed point number with a
616 	 * 4-bit (1/16ths) fraction, then round it to the nearest fraction the
617 	 * hardware can handle.  When the integral part of the divisor is
618 	 * greater than one, the fractional part is in 1/8ths of the base clock.
619 	 * The FT8U232AM chips can handle only 0.125, 0.250, and 0.5 fractions.
620 	 * Later chips can handle all 1/8th fractions.
621 	 *
622 	 * If the integral part of the divisor is 1, a special rule applies: the
623 	 * fractional part can only be .0 or .5 (this is a limitation of the
624 	 * hardware).  We handle this by truncating the fraction rather than
625 	 * rounding, because this only applies to the two fastest speeds the
626 	 * chip can achieve and rounding doesn't matter, either you've asked for
627 	 * that exact speed or you've asked for something the chip can't do.
628 	 *
629 	 * For the FT8U232AM chips, use a roundoff table to adjust the result
630 	 * to the nearest 1/8th fraction that is supported by the hardware,
631 	 * leaving a fixed-point number with a 3-bit fraction which exactly
632 	 * represents the math the hardware divider will do.  For later-series
633 	 * chips that support all 8 fractional divisors, just round 16ths to
634 	 * 8ths by adding 1 and dividing by 2.
635 	 */
636 	divisor = (clk << 4) / speed;
637 	if ((divisor & 0xf) == 1)
638 		divisor &= 0xfffffff8;
639 	else if (sc->sc_flags & FLAGS_ROUNDOFF_232A)
640 		divisor += roundoff_232a[divisor & 0x0f];
641 	else
642 		divisor += 1;  /* Rounds odd 16ths up to next 8th. */
643 	divisor >>= 1;
644 
645 	/*
646 	 * Ensure the resulting hardware speed will be within operational
647 	 * tolerance (within 3% of nominal).
648 	 */
649 	hwspeed = (clk << 3) / divisor;
650 	if (!uftdi_baud_within_tolerance(hwspeed, speed))
651 		return -1;
652 
653 	/*
654 	 * Re-pack the divisor into hardware format. The lower 14-bits hold the
655 	 * integral part, while the upper bits specify the fraction by indexing
656 	 * a table of fractions within the hardware which is laid out as:
657 	 *    {0.0, 0.5, 0.25, 0.125, 0.325, 0.625, 0.725, 0.875}
658 	 * The A-series chips only have the first four table entries; the
659 	 * roundoff table logic above ensures that the fractional part for those
660 	 * chips will be one of the first four values.
661 	 *
662 	 * When the divisor is 1 a special encoding applies:  1.0 is encoded as
663 	 * 0.0, and 1.5 is encoded as 1.0.  The rounding logic above has already
664 	 * ensured that the fraction is either .0 or .5 if the integral is 1.
665 	 */
666 	frac = divisor & 0x07;
667 	divisor >>= 3;
668 	if (divisor == 1) {
669 		if (frac == 0)
670 			divisor = 0;	/* 1.0 becomes 0.0 */
671 		else
672 			frac = 0;	/* 1.5 becomes 1.0 */
673 	}
674 	divisor |= (encoded_fraction[frac] << 14) | fastclk_flag;
675 
676 	*rate = (uint16_t)divisor;
677 	*ratehi = (uint16_t)(divisor >> 16);
678 
679 	/*
680 	 * If this chip requires the baud bits to be in the high byte of the
681 	 * index word, move the bits up to that location.
682 	 */
683 	if (sc->sc_flags & FLAGS_BAUDBITS_HINDEX)
684 		*ratehi <<= 8;
685 
686 	return 0;
687 }
688 
689 static int
690 uftdi_param(void *vsc, int portno, struct termios *t)
691 {
692 	struct uftdi_softc *sc = vsc;
693 	usb_device_request_t req;
694 	usbd_status err;
695 	int rate, ratehi, rerr, data, flow;
696 
697 	DPRINTF(("uftdi_param: sc=%p\n", sc));
698 
699 	if (sc->sc_dying)
700 		return EIO;
701 
702 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
703 	req.bRequest = FTDI_SIO_SET_BITMODE;
704 	USETW(req.wValue, FTDI_BITMODE_RESET << 8 | 0x00);
705 	USETW(req.wIndex, portno);
706 	USETW(req.wLength, 0);
707 	err = usbd_do_request(sc->sc_udev, &req, NULL);
708 	if (err)
709 		return EIO;
710 
711 	switch (sc->sc_type) {
712 	case UFTDI_TYPE_SIO:
713 		switch (t->c_ospeed) {
714 		case 300: rate = ftdi_sio_b300; break;
715 		case 600: rate = ftdi_sio_b600; break;
716 		case 1200: rate = ftdi_sio_b1200; break;
717 		case 2400: rate = ftdi_sio_b2400; break;
718 		case 4800: rate = ftdi_sio_b4800; break;
719 		case 9600: rate = ftdi_sio_b9600; break;
720 		case 19200: rate = ftdi_sio_b19200; break;
721 		case 38400: rate = ftdi_sio_b38400; break;
722 		case 57600: rate = ftdi_sio_b57600; break;
723 		case 115200: rate = ftdi_sio_b115200; break;
724 		default:
725 			return EINVAL;
726 		}
727 		ratehi = 0;
728 		break;
729 	case UFTDI_TYPE_8U232AM:
730 		rerr = uftdi_encode_baudrate(sc, t->c_ospeed, &rate, &ratehi);
731 		if (rerr != 0)
732 			return EINVAL;
733 		break;
734 	default:
735 		return EINVAL;
736 	}
737 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
738 	req.bRequest = FTDI_SIO_SET_BAUD_RATE;
739 	USETW(req.wValue, rate);
740 	USETW(req.wIndex, portno | ratehi);
741 	USETW(req.wLength, 0);
742 	DPRINTFN(2,("uftdi_param: reqtype=0x%02x req=0x%02x value=0x%04x "
743 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
744 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
745 	err = usbd_do_request(sc->sc_udev, &req, NULL);
746 	if (err)
747 		return EIO;
748 
749 	if (ISSET(t->c_cflag, CSTOPB))
750 		data = FTDI_SIO_SET_DATA_STOP_BITS_2;
751 	else
752 		data = FTDI_SIO_SET_DATA_STOP_BITS_1;
753 	if (ISSET(t->c_cflag, PARENB)) {
754 		if (ISSET(t->c_cflag, PARODD))
755 			data |= FTDI_SIO_SET_DATA_PARITY_ODD;
756 		else
757 			data |= FTDI_SIO_SET_DATA_PARITY_EVEN;
758 	} else
759 		data |= FTDI_SIO_SET_DATA_PARITY_NONE;
760 	switch (ISSET(t->c_cflag, CSIZE)) {
761 	case CS5:
762 		data |= FTDI_SIO_SET_DATA_BITS(5);
763 		break;
764 	case CS6:
765 		data |= FTDI_SIO_SET_DATA_BITS(6);
766 		break;
767 	case CS7:
768 		data |= FTDI_SIO_SET_DATA_BITS(7);
769 		break;
770 	case CS8:
771 		data |= FTDI_SIO_SET_DATA_BITS(8);
772 		break;
773 	}
774 	sc->last_lcr = data;
775 
776 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
777 	req.bRequest = FTDI_SIO_SET_DATA;
778 	USETW(req.wValue, data);
779 	USETW(req.wIndex, portno);
780 	USETW(req.wLength, 0);
781 	DPRINTFN(2,("uftdi_param: reqtype=0x%02x req=0x%02x value=0x%04x "
782 		    "index=0x%04x len=%d\n", req.bmRequestType, req.bRequest,
783 		    UGETW(req.wValue), UGETW(req.wIndex), UGETW(req.wLength)));
784 	err = usbd_do_request(sc->sc_udev, &req, NULL);
785 	if (err)
786 		return EIO;
787 
788 	if (ISSET(t->c_cflag, CRTSCTS)) {
789 		flow = FTDI_SIO_RTS_CTS_HS;
790 		USETW(req.wValue, 0);
791 	} else if (ISSET(t->c_iflag, IXON) && ISSET(t->c_iflag, IXOFF)) {
792 		flow = FTDI_SIO_XON_XOFF_HS;
793 		USETW2(req.wValue, t->c_cc[VSTOP], t->c_cc[VSTART]);
794 	} else {
795 		flow = FTDI_SIO_DISABLE_FLOW_CTRL;
796 		USETW(req.wValue, 0);
797 	}
798 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
799 	req.bRequest = FTDI_SIO_SET_FLOW_CTRL;
800 	USETW2(req.wIndex, flow, portno);
801 	USETW(req.wLength, 0);
802 	err = usbd_do_request(sc->sc_udev, &req, NULL);
803 	if (err)
804 		return EIO;
805 
806 	return 0;
807 }
808 
809 static void
810 uftdi_get_status(void *vsc, int portno, u_char *lsr, u_char *msr)
811 {
812 	struct uftdi_softc *sc = vsc;
813 
814 	DPRINTF(("uftdi_status: msr=0x%02x lsr=0x%02x\n",
815 		 sc->sc_msr, sc->sc_lsr));
816 
817 	if (sc->sc_dying)
818 		return;
819 
820 	*msr = sc->sc_msr;
821 	*lsr = sc->sc_lsr;
822 }
823 
824 static void
825 uftdi_break(void *vsc, int portno, int onoff)
826 {
827 	struct uftdi_softc *sc = vsc;
828 	usb_device_request_t req;
829 	int data;
830 
831 	DPRINTF(("uftdi_break: sc=%p, port=%d onoff=%d\n", vsc, portno,
832 		  onoff));
833 
834 	if (onoff) {
835 		data = sc->last_lcr | FTDI_SIO_SET_BREAK;
836 	} else {
837 		data = sc->last_lcr;
838 	}
839 
840 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
841 	req.bRequest = FTDI_SIO_SET_DATA;
842 	USETW(req.wValue, data);
843 	USETW(req.wIndex, portno);
844 	USETW(req.wLength, 0);
845 	(void)usbd_do_request(sc->sc_udev, &req, NULL);
846 }
847