xref: /freebsd/sys/dev/usb/serial/usb_serial.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 /*	$NetBSD: ucom.c,v 1.40 2001/11/13 06:24:54 lukem Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001-2003, 2005, 2008
5  *	Shunsuke Akiyama <akiyama@jp.FreeBSD.org>.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 /*-
34  * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
35  * All rights reserved.
36  *
37  * This code is derived from software contributed to The NetBSD Foundation
38  * by Lennart Augustsson (lennart@augustsson.net) at
39  * Carlstedt Research & Technology.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
51  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
52  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
53  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
54  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
55  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
56  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
57  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
58  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
59  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
60  * POSSIBILITY OF SUCH DAMAGE.
61  */
62 
63 #include <sys/stdint.h>
64 #include <sys/stddef.h>
65 #include <sys/param.h>
66 #include <sys/queue.h>
67 #include <sys/types.h>
68 #include <sys/systm.h>
69 #include <sys/kernel.h>
70 #include <sys/bus.h>
71 #include <sys/module.h>
72 #include <sys/lock.h>
73 #include <sys/mutex.h>
74 #include <sys/condvar.h>
75 #include <sys/sysctl.h>
76 #include <sys/sx.h>
77 #include <sys/unistd.h>
78 #include <sys/callout.h>
79 #include <sys/malloc.h>
80 #include <sys/priv.h>
81 #include <sys/cons.h>
82 #include <sys/kdb.h>
83 
84 #include <dev/uart/uart_ppstypes.h>
85 
86 #include <dev/usb/usb.h>
87 #include <dev/usb/usbdi.h>
88 #include <dev/usb/usbdi_util.h>
89 
90 #define	USB_DEBUG_VAR ucom_debug
91 #include <dev/usb/usb_debug.h>
92 #include <dev/usb/usb_busdma.h>
93 #include <dev/usb/usb_process.h>
94 
95 #include <dev/usb/serial/usb_serial.h>
96 
97 #include "opt_gdb.h"
98 
99 static SYSCTL_NODE(_hw_usb, OID_AUTO, ucom, CTLFLAG_RW, 0, "USB ucom");
100 
101 static int ucom_pps_mode;
102 
103 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, pps_mode, CTLFLAG_RWTUN,
104     &ucom_pps_mode, 0,
105     "pulse capture mode: 0/1/2=disabled/CTS/DCD; add 0x10 to invert");
106 
107 #ifdef USB_DEBUG
108 static int ucom_debug = 0;
109 
110 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, debug, CTLFLAG_RWTUN,
111     &ucom_debug, 0, "ucom debug level");
112 #endif
113 
114 #define	UCOM_CONS_BUFSIZE 1024
115 
116 static uint8_t ucom_cons_rx_buf[UCOM_CONS_BUFSIZE];
117 static uint8_t ucom_cons_tx_buf[UCOM_CONS_BUFSIZE];
118 
119 static unsigned int ucom_cons_rx_low = 0;
120 static unsigned int ucom_cons_rx_high = 0;
121 
122 static unsigned int ucom_cons_tx_low = 0;
123 static unsigned int ucom_cons_tx_high = 0;
124 
125 static int ucom_cons_unit = -1;
126 static int ucom_cons_subunit = 0;
127 static int ucom_cons_baud = 9600;
128 static struct ucom_softc *ucom_cons_softc = NULL;
129 
130 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_unit, CTLFLAG_RWTUN,
131     &ucom_cons_unit, 0, "console unit number");
132 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_subunit, CTLFLAG_RWTUN,
133     &ucom_cons_subunit, 0, "console subunit number");
134 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_baud, CTLFLAG_RWTUN,
135     &ucom_cons_baud, 0, "console baud rate");
136 
137 static usb_proc_callback_t ucom_cfg_start_transfers;
138 static usb_proc_callback_t ucom_cfg_open;
139 static usb_proc_callback_t ucom_cfg_close;
140 static usb_proc_callback_t ucom_cfg_line_state;
141 static usb_proc_callback_t ucom_cfg_status_change;
142 static usb_proc_callback_t ucom_cfg_param;
143 
144 static int	ucom_unit_alloc(void);
145 static void	ucom_unit_free(int);
146 static int	ucom_attach_tty(struct ucom_super_softc *, struct ucom_softc *);
147 static void	ucom_detach_tty(struct ucom_super_softc *, struct ucom_softc *);
148 static void	ucom_queue_command(struct ucom_softc *,
149 		    usb_proc_callback_t *, struct termios *pt,
150 		    struct usb_proc_msg *t0, struct usb_proc_msg *t1);
151 static void	ucom_shutdown(struct ucom_softc *);
152 static void	ucom_ring(struct ucom_softc *, uint8_t);
153 static void	ucom_break(struct ucom_softc *, uint8_t);
154 static void	ucom_dtr(struct ucom_softc *, uint8_t);
155 static void	ucom_rts(struct ucom_softc *, uint8_t);
156 
157 static tsw_open_t ucom_open;
158 static tsw_close_t ucom_close;
159 static tsw_ioctl_t ucom_ioctl;
160 static tsw_modem_t ucom_modem;
161 static tsw_param_t ucom_param;
162 static tsw_outwakeup_t ucom_outwakeup;
163 static tsw_inwakeup_t ucom_inwakeup;
164 static tsw_free_t ucom_free;
165 
166 static struct ttydevsw ucom_class = {
167 	.tsw_flags = TF_INITLOCK | TF_CALLOUT,
168 	.tsw_open = ucom_open,
169 	.tsw_close = ucom_close,
170 	.tsw_outwakeup = ucom_outwakeup,
171 	.tsw_inwakeup = ucom_inwakeup,
172 	.tsw_ioctl = ucom_ioctl,
173 	.tsw_param = ucom_param,
174 	.tsw_modem = ucom_modem,
175 	.tsw_free = ucom_free,
176 };
177 
178 MODULE_DEPEND(ucom, usb, 1, 1, 1);
179 MODULE_VERSION(ucom, 1);
180 
181 #define	UCOM_UNIT_MAX 		128	/* maximum number of units */
182 #define	UCOM_TTY_PREFIX		"U"
183 
184 static struct unrhdr *ucom_unrhdr;
185 static struct mtx ucom_mtx;
186 static int ucom_close_refs;
187 
188 static void
189 ucom_init(void *arg)
190 {
191 	DPRINTF("\n");
192 	ucom_unrhdr = new_unrhdr(0, UCOM_UNIT_MAX - 1, NULL);
193 	mtx_init(&ucom_mtx, "UCOM MTX", NULL, MTX_DEF);
194 }
195 SYSINIT(ucom_init, SI_SUB_KLD - 1, SI_ORDER_ANY, ucom_init, NULL);
196 
197 static void
198 ucom_uninit(void *arg)
199 {
200 	struct unrhdr *hdr;
201 	hdr = ucom_unrhdr;
202 	ucom_unrhdr = NULL;
203 
204 	DPRINTF("\n");
205 
206 	if (hdr != NULL)
207 		delete_unrhdr(hdr);
208 
209 	mtx_destroy(&ucom_mtx);
210 }
211 SYSUNINIT(ucom_uninit, SI_SUB_KLD - 3, SI_ORDER_ANY, ucom_uninit, NULL);
212 
213 /*
214  * Mark a unit number (the X in cuaUX) as in use.
215  *
216  * Note that devices using a different naming scheme (see ucom_tty_name()
217  * callback) still use this unit allocation.
218  */
219 static int
220 ucom_unit_alloc(void)
221 {
222 	int unit;
223 
224 	/* sanity checks */
225 	if (ucom_unrhdr == NULL) {
226 		DPRINTF("ucom_unrhdr is NULL\n");
227 		return (-1);
228 	}
229 	unit = alloc_unr(ucom_unrhdr);
230 	DPRINTF("unit %d is allocated\n", unit);
231 	return (unit);
232 }
233 
234 /*
235  * Mark the unit number as not in use.
236  */
237 static void
238 ucom_unit_free(int unit)
239 {
240 	/* sanity checks */
241 	if (unit < 0 || unit >= UCOM_UNIT_MAX || ucom_unrhdr == NULL) {
242 		DPRINTF("cannot free unit number\n");
243 		return;
244 	}
245 	DPRINTF("unit %d is freed\n", unit);
246 	free_unr(ucom_unrhdr, unit);
247 }
248 
249 /*
250  * Setup a group of one or more serial ports.
251  *
252  * The mutex pointed to by "mtx" is applied before all
253  * callbacks are called back. Also "mtx" must be applied
254  * before calling into the ucom-layer!
255  */
256 int
257 ucom_attach(struct ucom_super_softc *ssc, struct ucom_softc *sc,
258     int subunits, void *parent,
259     const struct ucom_callback *callback, struct mtx *mtx)
260 {
261 	int subunit;
262 	int error = 0;
263 
264 	if ((sc == NULL) ||
265 	    (subunits <= 0) ||
266 	    (callback == NULL) ||
267 	    (mtx == NULL)) {
268 		return (EINVAL);
269 	}
270 
271 	/* allocate a uniq unit number */
272 	ssc->sc_unit = ucom_unit_alloc();
273 	if (ssc->sc_unit == -1)
274 		return (ENOMEM);
275 
276 	/* generate TTY name string */
277 	snprintf(ssc->sc_ttyname, sizeof(ssc->sc_ttyname),
278 	    UCOM_TTY_PREFIX "%d", ssc->sc_unit);
279 
280 	/* create USB request handling process */
281 	error = usb_proc_create(&ssc->sc_tq, mtx, "ucom", USB_PRI_MED);
282 	if (error) {
283 		ucom_unit_free(ssc->sc_unit);
284 		return (error);
285 	}
286 	ssc->sc_subunits = subunits;
287 	ssc->sc_flag = UCOM_FLAG_ATTACHED |
288 	    UCOM_FLAG_FREE_UNIT;
289 
290 	if (callback->ucom_free == NULL)
291 		ssc->sc_flag |= UCOM_FLAG_WAIT_REFS;
292 
293 	/* increment reference count */
294 	ucom_ref(ssc);
295 
296 	for (subunit = 0; subunit < ssc->sc_subunits; subunit++) {
297 		sc[subunit].sc_subunit = subunit;
298 		sc[subunit].sc_super = ssc;
299 		sc[subunit].sc_mtx = mtx;
300 		sc[subunit].sc_parent = parent;
301 		sc[subunit].sc_callback = callback;
302 
303 		error = ucom_attach_tty(ssc, &sc[subunit]);
304 		if (error) {
305 			ucom_detach(ssc, &sc[0]);
306 			return (error);
307 		}
308 		/* increment reference count */
309 		ucom_ref(ssc);
310 
311 		/* set subunit attached */
312 		sc[subunit].sc_flag |= UCOM_FLAG_ATTACHED;
313 	}
314 
315 	DPRINTF("tp = %p, unit = %d, subunits = %d\n",
316 		sc->sc_tty, ssc->sc_unit, ssc->sc_subunits);
317 
318 	return (0);
319 }
320 
321 /*
322  * The following function will do nothing if the structure pointed to
323  * by "ssc" and "sc" is zero or has already been detached.
324  */
325 void
326 ucom_detach(struct ucom_super_softc *ssc, struct ucom_softc *sc)
327 {
328 	int subunit;
329 
330 	if (!(ssc->sc_flag & UCOM_FLAG_ATTACHED))
331 		return;		/* not initialized */
332 
333 	if (ssc->sc_sysctl_ttyname != NULL) {
334 		sysctl_remove_oid(ssc->sc_sysctl_ttyname, 1, 0);
335 		ssc->sc_sysctl_ttyname = NULL;
336 	}
337 
338 	if (ssc->sc_sysctl_ttyports != NULL) {
339 		sysctl_remove_oid(ssc->sc_sysctl_ttyports, 1, 0);
340 		ssc->sc_sysctl_ttyports = NULL;
341 	}
342 
343 	usb_proc_drain(&ssc->sc_tq);
344 
345 	for (subunit = 0; subunit < ssc->sc_subunits; subunit++) {
346 		if (sc[subunit].sc_flag & UCOM_FLAG_ATTACHED) {
347 
348 			ucom_detach_tty(ssc, &sc[subunit]);
349 
350 			/* avoid duplicate detach */
351 			sc[subunit].sc_flag &= ~UCOM_FLAG_ATTACHED;
352 		}
353 	}
354 	usb_proc_free(&ssc->sc_tq);
355 
356 	ucom_unref(ssc);
357 
358 	if (ssc->sc_flag & UCOM_FLAG_WAIT_REFS)
359 		ucom_drain(ssc);
360 
361 	/* make sure we don't detach twice */
362 	ssc->sc_flag &= ~UCOM_FLAG_ATTACHED;
363 }
364 
365 void
366 ucom_drain(struct ucom_super_softc *ssc)
367 {
368 	mtx_lock(&ucom_mtx);
369 	while (ssc->sc_refs > 0) {
370 		printf("ucom: Waiting for a TTY device to close.\n");
371 		usb_pause_mtx(&ucom_mtx, hz);
372 	}
373 	mtx_unlock(&ucom_mtx);
374 }
375 
376 void
377 ucom_drain_all(void *arg)
378 {
379 	mtx_lock(&ucom_mtx);
380 	while (ucom_close_refs > 0) {
381 		printf("ucom: Waiting for all detached TTY "
382 		    "devices to have open fds closed.\n");
383 		usb_pause_mtx(&ucom_mtx, hz);
384 	}
385 	mtx_unlock(&ucom_mtx);
386 }
387 
388 static int
389 ucom_attach_tty(struct ucom_super_softc *ssc, struct ucom_softc *sc)
390 {
391 	struct tty *tp;
392 	char buf[32];			/* temporary TTY device name buffer */
393 
394 	tp = tty_alloc_mutex(&ucom_class, sc, sc->sc_mtx);
395 	if (tp == NULL)
396 		return (ENOMEM);
397 
398 	/* Check if the client has a custom TTY name */
399 	buf[0] = '\0';
400 	if (sc->sc_callback->ucom_tty_name) {
401 		sc->sc_callback->ucom_tty_name(sc, buf,
402 		    sizeof(buf), ssc->sc_unit, sc->sc_subunit);
403 	}
404 	if (buf[0] == 0) {
405 		/* Use default TTY name */
406 		if (ssc->sc_subunits > 1) {
407 			/* multiple modems in one */
408 			snprintf(buf, sizeof(buf), UCOM_TTY_PREFIX "%u.%u",
409 			    ssc->sc_unit, sc->sc_subunit);
410 		} else {
411 			/* single modem */
412 			snprintf(buf, sizeof(buf), UCOM_TTY_PREFIX "%u",
413 			    ssc->sc_unit);
414 		}
415 	}
416 	tty_makedev(tp, NULL, "%s", buf);
417 
418 	sc->sc_tty = tp;
419 
420 	sc->sc_pps.ppscap = PPS_CAPTUREBOTH;
421 	sc->sc_pps.driver_abi = PPS_ABI_VERSION;
422 	sc->sc_pps.driver_mtx = sc->sc_mtx;
423 	pps_init_abi(&sc->sc_pps);
424 
425 	DPRINTF("ttycreate: %s\n", buf);
426 
427 	/* Check if this device should be a console */
428 	if ((ucom_cons_softc == NULL) &&
429 	    (ssc->sc_unit == ucom_cons_unit) &&
430 	    (sc->sc_subunit == ucom_cons_subunit)) {
431 
432 		DPRINTF("unit %d subunit %d is console",
433 		    ssc->sc_unit, sc->sc_subunit);
434 
435 		ucom_cons_softc = sc;
436 
437 		tty_init_console(tp, ucom_cons_baud);
438 
439 		UCOM_MTX_LOCK(ucom_cons_softc);
440 		ucom_cons_rx_low = 0;
441 		ucom_cons_rx_high = 0;
442 		ucom_cons_tx_low = 0;
443 		ucom_cons_tx_high = 0;
444 		sc->sc_flag |= UCOM_FLAG_CONSOLE;
445 		ucom_open(ucom_cons_softc->sc_tty);
446 		ucom_param(ucom_cons_softc->sc_tty, &tp->t_termios_init_in);
447 		UCOM_MTX_UNLOCK(ucom_cons_softc);
448 	}
449 
450 	return (0);
451 }
452 
453 static void
454 ucom_detach_tty(struct ucom_super_softc *ssc, struct ucom_softc *sc)
455 {
456 	struct tty *tp = sc->sc_tty;
457 
458 	DPRINTF("sc = %p, tp = %p\n", sc, sc->sc_tty);
459 
460 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
461 		UCOM_MTX_LOCK(ucom_cons_softc);
462 		ucom_close(ucom_cons_softc->sc_tty);
463 		sc->sc_flag &= ~UCOM_FLAG_CONSOLE;
464 		UCOM_MTX_UNLOCK(ucom_cons_softc);
465 		ucom_cons_softc = NULL;
466 	}
467 
468 	/* the config thread has been stopped when we get here */
469 
470 	UCOM_MTX_LOCK(sc);
471 	sc->sc_flag |= UCOM_FLAG_GONE;
472 	sc->sc_flag &= ~(UCOM_FLAG_HL_READY | UCOM_FLAG_LL_READY);
473 	UCOM_MTX_UNLOCK(sc);
474 
475 	if (tp) {
476 		mtx_lock(&ucom_mtx);
477 		ucom_close_refs++;
478 		mtx_unlock(&ucom_mtx);
479 
480 		tty_lock(tp);
481 
482 		ucom_close(tp);	/* close, if any */
483 
484 		tty_rel_gone(tp);
485 
486 		UCOM_MTX_LOCK(sc);
487 		/*
488 		 * make sure that read and write transfers are stopped
489 		 */
490 		if (sc->sc_callback->ucom_stop_read)
491 			(sc->sc_callback->ucom_stop_read) (sc);
492 		if (sc->sc_callback->ucom_stop_write)
493 			(sc->sc_callback->ucom_stop_write) (sc);
494 		UCOM_MTX_UNLOCK(sc);
495 	}
496 }
497 
498 void
499 ucom_set_pnpinfo_usb(struct ucom_super_softc *ssc, device_t dev)
500 {
501 	char buf[64];
502 	uint8_t iface_index;
503 	struct usb_attach_arg *uaa;
504 
505 	snprintf(buf, sizeof(buf), "ttyname=" UCOM_TTY_PREFIX
506 	    "%d ttyports=%d", ssc->sc_unit, ssc->sc_subunits);
507 
508 	/* Store the PNP info in the first interface for the device */
509 	uaa = device_get_ivars(dev);
510 	iface_index = uaa->info.bIfaceIndex;
511 
512 	if (usbd_set_pnpinfo(uaa->device, iface_index, buf) != 0)
513 		device_printf(dev, "Could not set PNP info\n");
514 
515 	/*
516 	 * The following information is also replicated in the PNP-info
517 	 * string which is registered above:
518 	 */
519 	if (ssc->sc_sysctl_ttyname == NULL) {
520 		ssc->sc_sysctl_ttyname = SYSCTL_ADD_STRING(NULL,
521 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
522 		    OID_AUTO, "ttyname", CTLFLAG_RD, ssc->sc_ttyname, 0,
523 		    "TTY device basename");
524 	}
525 	if (ssc->sc_sysctl_ttyports == NULL) {
526 		ssc->sc_sysctl_ttyports = SYSCTL_ADD_INT(NULL,
527 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
528 		    OID_AUTO, "ttyports", CTLFLAG_RD,
529 		    NULL, ssc->sc_subunits, "Number of ports");
530 	}
531 }
532 
533 static void
534 ucom_queue_command(struct ucom_softc *sc,
535     usb_proc_callback_t *fn, struct termios *pt,
536     struct usb_proc_msg *t0, struct usb_proc_msg *t1)
537 {
538 	struct ucom_super_softc *ssc = sc->sc_super;
539 	struct ucom_param_task *task;
540 
541 	UCOM_MTX_ASSERT(sc, MA_OWNED);
542 
543 	if (usb_proc_is_gone(&ssc->sc_tq)) {
544 		DPRINTF("proc is gone\n");
545 		return;         /* nothing to do */
546 	}
547 	/*
548 	 * NOTE: The task cannot get executed before we drop the
549 	 * "sc_mtx" mutex. It is safe to update fields in the message
550 	 * structure after that the message got queued.
551 	 */
552 	task = (struct ucom_param_task *)
553 	  usb_proc_msignal(&ssc->sc_tq, t0, t1);
554 
555 	/* Setup callback and softc pointers */
556 	task->hdr.pm_callback = fn;
557 	task->sc = sc;
558 
559 	/*
560 	 * Make a copy of the termios. This field is only present if
561 	 * the "pt" field is not NULL.
562 	 */
563 	if (pt != NULL)
564 		task->termios_copy = *pt;
565 
566 	/*
567 	 * Closing the device should be synchronous.
568 	 */
569 	if (fn == ucom_cfg_close)
570 		usb_proc_mwait(&ssc->sc_tq, t0, t1);
571 
572 	/*
573 	 * In case of multiple configure requests,
574 	 * keep track of the last one!
575 	 */
576 	if (fn == ucom_cfg_start_transfers)
577 		sc->sc_last_start_xfer = &task->hdr;
578 }
579 
580 static void
581 ucom_shutdown(struct ucom_softc *sc)
582 {
583 	struct tty *tp = sc->sc_tty;
584 
585 	UCOM_MTX_ASSERT(sc, MA_OWNED);
586 
587 	DPRINTF("\n");
588 
589 	/*
590 	 * Hang up if necessary:
591 	 */
592 	if (tp->t_termios.c_cflag & HUPCL) {
593 		ucom_modem(tp, 0, SER_DTR);
594 	}
595 }
596 
597 /*
598  * Return values:
599  *    0: normal
600  * else: taskqueue is draining or gone
601  */
602 uint8_t
603 ucom_cfg_is_gone(struct ucom_softc *sc)
604 {
605 	struct ucom_super_softc *ssc = sc->sc_super;
606 
607 	return (usb_proc_is_gone(&ssc->sc_tq));
608 }
609 
610 static void
611 ucom_cfg_start_transfers(struct usb_proc_msg *_task)
612 {
613 	struct ucom_cfg_task *task =
614 	    (struct ucom_cfg_task *)_task;
615 	struct ucom_softc *sc = task->sc;
616 
617 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
618 		return;
619 	}
620 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
621 		/* TTY device closed */
622 		return;
623 	}
624 
625 	if (_task == sc->sc_last_start_xfer)
626 		sc->sc_flag |= UCOM_FLAG_GP_DATA;
627 
628 	if (sc->sc_callback->ucom_start_read) {
629 		(sc->sc_callback->ucom_start_read) (sc);
630 	}
631 	if (sc->sc_callback->ucom_start_write) {
632 		(sc->sc_callback->ucom_start_write) (sc);
633 	}
634 }
635 
636 static void
637 ucom_start_transfers(struct ucom_softc *sc)
638 {
639 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
640 		return;
641 	}
642 	/*
643 	 * Make sure that data transfers are started in both
644 	 * directions:
645 	 */
646 	if (sc->sc_callback->ucom_start_read) {
647 		(sc->sc_callback->ucom_start_read) (sc);
648 	}
649 	if (sc->sc_callback->ucom_start_write) {
650 		(sc->sc_callback->ucom_start_write) (sc);
651 	}
652 }
653 
654 static void
655 ucom_cfg_open(struct usb_proc_msg *_task)
656 {
657 	struct ucom_cfg_task *task =
658 	    (struct ucom_cfg_task *)_task;
659 	struct ucom_softc *sc = task->sc;
660 
661 	DPRINTF("\n");
662 
663 	if (sc->sc_flag & UCOM_FLAG_LL_READY) {
664 
665 		/* already opened */
666 
667 	} else {
668 
669 		sc->sc_flag |= UCOM_FLAG_LL_READY;
670 
671 		if (sc->sc_callback->ucom_cfg_open) {
672 			(sc->sc_callback->ucom_cfg_open) (sc);
673 
674 			/* wait a little */
675 			usb_pause_mtx(sc->sc_mtx, hz / 10);
676 		}
677 	}
678 }
679 
680 static int
681 ucom_open(struct tty *tp)
682 {
683 	struct ucom_softc *sc = tty_softc(tp);
684 	int error;
685 
686 	UCOM_MTX_ASSERT(sc, MA_OWNED);
687 
688 	if (sc->sc_flag & UCOM_FLAG_GONE) {
689 		return (ENXIO);
690 	}
691 	if (sc->sc_flag & UCOM_FLAG_HL_READY) {
692 		/* already opened */
693 		return (0);
694 	}
695 	DPRINTF("tp = %p\n", tp);
696 
697 	if (sc->sc_callback->ucom_pre_open) {
698 		/*
699 		 * give the lower layer a chance to disallow TTY open, for
700 		 * example if the device is not present:
701 		 */
702 		error = (sc->sc_callback->ucom_pre_open) (sc);
703 		if (error) {
704 			return (error);
705 		}
706 	}
707 	sc->sc_flag |= UCOM_FLAG_HL_READY;
708 
709 	/* Disable transfers */
710 	sc->sc_flag &= ~UCOM_FLAG_GP_DATA;
711 
712 	sc->sc_lsr = 0;
713 	sc->sc_msr = 0;
714 	sc->sc_mcr = 0;
715 
716 	/* reset programmed line state */
717 	sc->sc_pls_curr = 0;
718 	sc->sc_pls_set = 0;
719 	sc->sc_pls_clr = 0;
720 
721 	/* reset jitter buffer */
722 	sc->sc_jitterbuf_in = 0;
723 	sc->sc_jitterbuf_out = 0;
724 
725 	ucom_queue_command(sc, ucom_cfg_open, NULL,
726 	    &sc->sc_open_task[0].hdr,
727 	    &sc->sc_open_task[1].hdr);
728 
729 	/* Queue transfer enable command last */
730 	ucom_queue_command(sc, ucom_cfg_start_transfers, NULL,
731 	    &sc->sc_start_task[0].hdr,
732 	    &sc->sc_start_task[1].hdr);
733 
734 	ucom_modem(tp, SER_DTR | SER_RTS, 0);
735 
736 	ucom_ring(sc, 0);
737 
738 	ucom_break(sc, 0);
739 
740 	ucom_status_change(sc);
741 
742 	return (0);
743 }
744 
745 static void
746 ucom_cfg_close(struct usb_proc_msg *_task)
747 {
748 	struct ucom_cfg_task *task =
749 	    (struct ucom_cfg_task *)_task;
750 	struct ucom_softc *sc = task->sc;
751 
752 	DPRINTF("\n");
753 
754 	if (sc->sc_flag & UCOM_FLAG_LL_READY) {
755 		sc->sc_flag &= ~UCOM_FLAG_LL_READY;
756 		if (sc->sc_callback->ucom_cfg_close)
757 			(sc->sc_callback->ucom_cfg_close) (sc);
758 	} else {
759 		/* already closed */
760 	}
761 }
762 
763 static void
764 ucom_close(struct tty *tp)
765 {
766 	struct ucom_softc *sc = tty_softc(tp);
767 
768 	UCOM_MTX_ASSERT(sc, MA_OWNED);
769 
770 	DPRINTF("tp=%p\n", tp);
771 
772 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
773 		DPRINTF("tp=%p already closed\n", tp);
774 		return;
775 	}
776 	ucom_shutdown(sc);
777 
778 	ucom_queue_command(sc, ucom_cfg_close, NULL,
779 	    &sc->sc_close_task[0].hdr,
780 	    &sc->sc_close_task[1].hdr);
781 
782 	sc->sc_flag &= ~(UCOM_FLAG_HL_READY | UCOM_FLAG_RTS_IFLOW);
783 
784 	if (sc->sc_callback->ucom_stop_read) {
785 		(sc->sc_callback->ucom_stop_read) (sc);
786 	}
787 }
788 
789 static void
790 ucom_inwakeup(struct tty *tp)
791 {
792 	struct ucom_softc *sc = tty_softc(tp);
793 	uint16_t pos;
794 
795 	if (sc == NULL)
796 		return;
797 
798 	UCOM_MTX_ASSERT(sc, MA_OWNED);
799 
800 	DPRINTF("tp=%p\n", tp);
801 
802 	if (ttydisc_can_bypass(tp) != 0 ||
803 	    (sc->sc_flag & UCOM_FLAG_HL_READY) == 0 ||
804 	    (sc->sc_flag & UCOM_FLAG_INWAKEUP) != 0) {
805 		return;
806 	}
807 
808 	/* prevent recursion */
809 	sc->sc_flag |= UCOM_FLAG_INWAKEUP;
810 
811 	pos = sc->sc_jitterbuf_out;
812 
813 	while (sc->sc_jitterbuf_in != pos) {
814 		int c;
815 
816 		c = (char)sc->sc_jitterbuf[pos];
817 
818 		if (ttydisc_rint(tp, c, 0) == -1)
819 			break;
820 		pos++;
821 		if (pos >= UCOM_JITTERBUF_SIZE)
822 			pos -= UCOM_JITTERBUF_SIZE;
823 	}
824 
825 	sc->sc_jitterbuf_out = pos;
826 
827 	/* clear RTS in async fashion */
828 	if ((sc->sc_jitterbuf_in == pos) &&
829 	    (sc->sc_flag & UCOM_FLAG_RTS_IFLOW))
830 		ucom_rts(sc, 0);
831 
832 	sc->sc_flag &= ~UCOM_FLAG_INWAKEUP;
833 }
834 
835 static int
836 ucom_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
837 {
838 	struct ucom_softc *sc = tty_softc(tp);
839 	int error;
840 
841 	UCOM_MTX_ASSERT(sc, MA_OWNED);
842 
843 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
844 		return (EIO);
845 	}
846 	DPRINTF("cmd = 0x%08lx\n", cmd);
847 
848 	switch (cmd) {
849 #if 0
850 	case TIOCSRING:
851 		ucom_ring(sc, 1);
852 		error = 0;
853 		break;
854 	case TIOCCRING:
855 		ucom_ring(sc, 0);
856 		error = 0;
857 		break;
858 #endif
859 	case TIOCSBRK:
860 		ucom_break(sc, 1);
861 		error = 0;
862 		break;
863 	case TIOCCBRK:
864 		ucom_break(sc, 0);
865 		error = 0;
866 		break;
867 	default:
868 		if (sc->sc_callback->ucom_ioctl) {
869 			error = (sc->sc_callback->ucom_ioctl)
870 			    (sc, cmd, data, 0, td);
871 		} else {
872 			error = ENOIOCTL;
873 		}
874 		if (error == ENOIOCTL)
875 			error = pps_ioctl(cmd, data, &sc->sc_pps);
876 		break;
877 	}
878 	return (error);
879 }
880 
881 static int
882 ucom_modem(struct tty *tp, int sigon, int sigoff)
883 {
884 	struct ucom_softc *sc = tty_softc(tp);
885 	uint8_t onoff;
886 
887 	UCOM_MTX_ASSERT(sc, MA_OWNED);
888 
889 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
890 		return (0);
891 	}
892 	if ((sigon == 0) && (sigoff == 0)) {
893 
894 		if (sc->sc_mcr & SER_DTR) {
895 			sigon |= SER_DTR;
896 		}
897 		if (sc->sc_mcr & SER_RTS) {
898 			sigon |= SER_RTS;
899 		}
900 		if (sc->sc_msr & SER_CTS) {
901 			sigon |= SER_CTS;
902 		}
903 		if (sc->sc_msr & SER_DCD) {
904 			sigon |= SER_DCD;
905 		}
906 		if (sc->sc_msr & SER_DSR) {
907 			sigon |= SER_DSR;
908 		}
909 		if (sc->sc_msr & SER_RI) {
910 			sigon |= SER_RI;
911 		}
912 		return (sigon);
913 	}
914 	if (sigon & SER_DTR) {
915 		sc->sc_mcr |= SER_DTR;
916 	}
917 	if (sigoff & SER_DTR) {
918 		sc->sc_mcr &= ~SER_DTR;
919 	}
920 	if (sigon & SER_RTS) {
921 		sc->sc_mcr |= SER_RTS;
922 	}
923 	if (sigoff & SER_RTS) {
924 		sc->sc_mcr &= ~SER_RTS;
925 	}
926 	onoff = (sc->sc_mcr & SER_DTR) ? 1 : 0;
927 	ucom_dtr(sc, onoff);
928 
929 	onoff = (sc->sc_mcr & SER_RTS) ? 1 : 0;
930 	ucom_rts(sc, onoff);
931 
932 	return (0);
933 }
934 
935 static void
936 ucom_cfg_line_state(struct usb_proc_msg *_task)
937 {
938 	struct ucom_cfg_task *task =
939 	    (struct ucom_cfg_task *)_task;
940 	struct ucom_softc *sc = task->sc;
941 	uint8_t notch_bits;
942 	uint8_t any_bits;
943 	uint8_t prev_value;
944 	uint8_t last_value;
945 	uint8_t mask;
946 
947 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
948 		return;
949 	}
950 
951 	mask = 0;
952 	/* compute callback mask */
953 	if (sc->sc_callback->ucom_cfg_set_dtr)
954 		mask |= UCOM_LS_DTR;
955 	if (sc->sc_callback->ucom_cfg_set_rts)
956 		mask |= UCOM_LS_RTS;
957 	if (sc->sc_callback->ucom_cfg_set_break)
958 		mask |= UCOM_LS_BREAK;
959 	if (sc->sc_callback->ucom_cfg_set_ring)
960 		mask |= UCOM_LS_RING;
961 
962 	/* compute the bits we are to program */
963 	notch_bits = (sc->sc_pls_set & sc->sc_pls_clr) & mask;
964 	any_bits = (sc->sc_pls_set | sc->sc_pls_clr) & mask;
965 	prev_value = sc->sc_pls_curr ^ notch_bits;
966 	last_value = sc->sc_pls_curr;
967 
968 	/* reset programmed line state */
969 	sc->sc_pls_curr = 0;
970 	sc->sc_pls_set = 0;
971 	sc->sc_pls_clr = 0;
972 
973 	/* ensure that we don't lose any levels */
974 	if (notch_bits & UCOM_LS_DTR)
975 		sc->sc_callback->ucom_cfg_set_dtr(sc,
976 		    (prev_value & UCOM_LS_DTR) ? 1 : 0);
977 	if (notch_bits & UCOM_LS_RTS)
978 		sc->sc_callback->ucom_cfg_set_rts(sc,
979 		    (prev_value & UCOM_LS_RTS) ? 1 : 0);
980 	if (notch_bits & UCOM_LS_BREAK)
981 		sc->sc_callback->ucom_cfg_set_break(sc,
982 		    (prev_value & UCOM_LS_BREAK) ? 1 : 0);
983 	if (notch_bits & UCOM_LS_RING)
984 		sc->sc_callback->ucom_cfg_set_ring(sc,
985 		    (prev_value & UCOM_LS_RING) ? 1 : 0);
986 
987 	/* set last value */
988 	if (any_bits & UCOM_LS_DTR)
989 		sc->sc_callback->ucom_cfg_set_dtr(sc,
990 		    (last_value & UCOM_LS_DTR) ? 1 : 0);
991 	if (any_bits & UCOM_LS_RTS)
992 		sc->sc_callback->ucom_cfg_set_rts(sc,
993 		    (last_value & UCOM_LS_RTS) ? 1 : 0);
994 	if (any_bits & UCOM_LS_BREAK)
995 		sc->sc_callback->ucom_cfg_set_break(sc,
996 		    (last_value & UCOM_LS_BREAK) ? 1 : 0);
997 	if (any_bits & UCOM_LS_RING)
998 		sc->sc_callback->ucom_cfg_set_ring(sc,
999 		    (last_value & UCOM_LS_RING) ? 1 : 0);
1000 }
1001 
1002 static void
1003 ucom_line_state(struct ucom_softc *sc,
1004     uint8_t set_bits, uint8_t clear_bits)
1005 {
1006 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1007 
1008 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1009 		return;
1010 	}
1011 
1012 	DPRINTF("on=0x%02x, off=0x%02x\n", set_bits, clear_bits);
1013 
1014 	/* update current programmed line state */
1015 	sc->sc_pls_curr |= set_bits;
1016 	sc->sc_pls_curr &= ~clear_bits;
1017 	sc->sc_pls_set |= set_bits;
1018 	sc->sc_pls_clr |= clear_bits;
1019 
1020 	/* defer driver programming */
1021 	ucom_queue_command(sc, ucom_cfg_line_state, NULL,
1022 	    &sc->sc_line_state_task[0].hdr,
1023 	    &sc->sc_line_state_task[1].hdr);
1024 }
1025 
1026 static void
1027 ucom_ring(struct ucom_softc *sc, uint8_t onoff)
1028 {
1029 	DPRINTF("onoff = %d\n", onoff);
1030 
1031 	if (onoff)
1032 		ucom_line_state(sc, UCOM_LS_RING, 0);
1033 	else
1034 		ucom_line_state(sc, 0, UCOM_LS_RING);
1035 }
1036 
1037 static void
1038 ucom_break(struct ucom_softc *sc, uint8_t onoff)
1039 {
1040 	DPRINTF("onoff = %d\n", onoff);
1041 
1042 	if (onoff)
1043 		ucom_line_state(sc, UCOM_LS_BREAK, 0);
1044 	else
1045 		ucom_line_state(sc, 0, UCOM_LS_BREAK);
1046 }
1047 
1048 static void
1049 ucom_dtr(struct ucom_softc *sc, uint8_t onoff)
1050 {
1051 	DPRINTF("onoff = %d\n", onoff);
1052 
1053 	if (onoff)
1054 		ucom_line_state(sc, UCOM_LS_DTR, 0);
1055 	else
1056 		ucom_line_state(sc, 0, UCOM_LS_DTR);
1057 }
1058 
1059 static void
1060 ucom_rts(struct ucom_softc *sc, uint8_t onoff)
1061 {
1062 	DPRINTF("onoff = %d\n", onoff);
1063 
1064 	if (onoff)
1065 		ucom_line_state(sc, UCOM_LS_RTS, 0);
1066 	else
1067 		ucom_line_state(sc, 0, UCOM_LS_RTS);
1068 }
1069 
1070 static void
1071 ucom_cfg_status_change(struct usb_proc_msg *_task)
1072 {
1073 	struct ucom_cfg_task *task =
1074 	    (struct ucom_cfg_task *)_task;
1075 	struct ucom_softc *sc = task->sc;
1076 	struct tty *tp;
1077 	int onoff;
1078 	uint8_t new_msr;
1079 	uint8_t new_lsr;
1080 	uint8_t msr_delta;
1081 	uint8_t lsr_delta;
1082 	uint8_t pps_signal;
1083 
1084 	tp = sc->sc_tty;
1085 
1086 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1087 
1088 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
1089 		return;
1090 	}
1091 	if (sc->sc_callback->ucom_cfg_get_status == NULL) {
1092 		return;
1093 	}
1094 	/* get status */
1095 
1096 	new_msr = 0;
1097 	new_lsr = 0;
1098 
1099 	(sc->sc_callback->ucom_cfg_get_status) (sc, &new_lsr, &new_msr);
1100 
1101 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1102 		/* TTY device closed */
1103 		return;
1104 	}
1105 	msr_delta = (sc->sc_msr ^ new_msr);
1106 	lsr_delta = (sc->sc_lsr ^ new_lsr);
1107 
1108 	sc->sc_msr = new_msr;
1109 	sc->sc_lsr = new_lsr;
1110 
1111 	/*
1112 	 * Time pulse counting support.
1113 	 */
1114 	switch(ucom_pps_mode & UART_PPS_SIGNAL_MASK) {
1115 	case UART_PPS_CTS:
1116 		pps_signal = SER_CTS;
1117 		break;
1118 	case UART_PPS_DCD:
1119 		pps_signal = SER_DCD;
1120 		break;
1121 	default:
1122 		pps_signal = 0;
1123 		break;
1124 	}
1125 
1126 	if ((sc->sc_pps.ppsparam.mode & PPS_CAPTUREBOTH) &&
1127 	    (msr_delta & pps_signal)) {
1128 		pps_capture(&sc->sc_pps);
1129 		onoff = (sc->sc_msr & pps_signal) ? 1 : 0;
1130 		if (ucom_pps_mode & UART_PPS_INVERT_PULSE)
1131 			onoff = !onoff;
1132 		pps_event(&sc->sc_pps, onoff ? PPS_CAPTUREASSERT :
1133 		    PPS_CAPTURECLEAR);
1134 	}
1135 
1136 	if (msr_delta & SER_DCD) {
1137 
1138 		onoff = (sc->sc_msr & SER_DCD) ? 1 : 0;
1139 
1140 		DPRINTF("DCD changed to %d\n", onoff);
1141 
1142 		ttydisc_modem(tp, onoff);
1143 	}
1144 
1145 	if ((lsr_delta & ULSR_BI) && (sc->sc_lsr & ULSR_BI)) {
1146 
1147 		DPRINTF("BREAK detected\n");
1148 
1149 		ttydisc_rint(tp, 0, TRE_BREAK);
1150 		ttydisc_rint_done(tp);
1151 	}
1152 
1153 	if ((lsr_delta & ULSR_FE) && (sc->sc_lsr & ULSR_FE)) {
1154 
1155 		DPRINTF("Frame error detected\n");
1156 
1157 		ttydisc_rint(tp, 0, TRE_FRAMING);
1158 		ttydisc_rint_done(tp);
1159 	}
1160 
1161 	if ((lsr_delta & ULSR_PE) && (sc->sc_lsr & ULSR_PE)) {
1162 
1163 		DPRINTF("Parity error detected\n");
1164 
1165 		ttydisc_rint(tp, 0, TRE_PARITY);
1166 		ttydisc_rint_done(tp);
1167 	}
1168 }
1169 
1170 void
1171 ucom_status_change(struct ucom_softc *sc)
1172 {
1173 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1174 
1175 	if (sc->sc_flag & UCOM_FLAG_CONSOLE)
1176 		return;		/* not supported */
1177 
1178 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1179 		return;
1180 	}
1181 	DPRINTF("\n");
1182 
1183 	ucom_queue_command(sc, ucom_cfg_status_change, NULL,
1184 	    &sc->sc_status_task[0].hdr,
1185 	    &sc->sc_status_task[1].hdr);
1186 }
1187 
1188 static void
1189 ucom_cfg_param(struct usb_proc_msg *_task)
1190 {
1191 	struct ucom_param_task *task =
1192 	    (struct ucom_param_task *)_task;
1193 	struct ucom_softc *sc = task->sc;
1194 
1195 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
1196 		return;
1197 	}
1198 	if (sc->sc_callback->ucom_cfg_param == NULL) {
1199 		return;
1200 	}
1201 
1202 	(sc->sc_callback->ucom_cfg_param) (sc, &task->termios_copy);
1203 
1204 	/* wait a little */
1205 	usb_pause_mtx(sc->sc_mtx, hz / 10);
1206 }
1207 
1208 static int
1209 ucom_param(struct tty *tp, struct termios *t)
1210 {
1211 	struct ucom_softc *sc = tty_softc(tp);
1212 	uint8_t opened;
1213 	int error;
1214 
1215 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1216 
1217 	opened = 0;
1218 	error = 0;
1219 
1220 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1221 
1222 		/* XXX the TTY layer should call "open()" first! */
1223 		/*
1224 		 * Not quite: Its ordering is partly backwards, but
1225 		 * some parameters must be set early in ttydev_open(),
1226 		 * possibly before calling ttydevsw_open().
1227 		 */
1228 		error = ucom_open(tp);
1229 		if (error)
1230 			goto done;
1231 
1232 		opened = 1;
1233 	}
1234 	DPRINTF("sc = %p\n", sc);
1235 
1236 	/* Check requested parameters. */
1237 	if (t->c_ispeed && (t->c_ispeed != t->c_ospeed)) {
1238 		/* XXX c_ospeed == 0 is perfectly valid. */
1239 		DPRINTF("mismatch ispeed and ospeed\n");
1240 		error = EINVAL;
1241 		goto done;
1242 	}
1243 	t->c_ispeed = t->c_ospeed;
1244 
1245 	if (sc->sc_callback->ucom_pre_param) {
1246 		/* Let the lower layer verify the parameters */
1247 		error = (sc->sc_callback->ucom_pre_param) (sc, t);
1248 		if (error) {
1249 			DPRINTF("callback error = %d\n", error);
1250 			goto done;
1251 		}
1252 	}
1253 
1254 	/* Disable transfers */
1255 	sc->sc_flag &= ~UCOM_FLAG_GP_DATA;
1256 
1257 	/* Queue baud rate programming command first */
1258 	ucom_queue_command(sc, ucom_cfg_param, t,
1259 	    &sc->sc_param_task[0].hdr,
1260 	    &sc->sc_param_task[1].hdr);
1261 
1262 	/* Queue transfer enable command last */
1263 	ucom_queue_command(sc, ucom_cfg_start_transfers, NULL,
1264 	    &sc->sc_start_task[0].hdr,
1265 	    &sc->sc_start_task[1].hdr);
1266 
1267 	if (t->c_cflag & CRTS_IFLOW) {
1268 		sc->sc_flag |= UCOM_FLAG_RTS_IFLOW;
1269 	} else if (sc->sc_flag & UCOM_FLAG_RTS_IFLOW) {
1270 		sc->sc_flag &= ~UCOM_FLAG_RTS_IFLOW;
1271 		ucom_modem(tp, SER_RTS, 0);
1272 	}
1273 done:
1274 	if (error) {
1275 		if (opened) {
1276 			ucom_close(tp);
1277 		}
1278 	}
1279 	return (error);
1280 }
1281 
1282 static void
1283 ucom_outwakeup(struct tty *tp)
1284 {
1285 	struct ucom_softc *sc = tty_softc(tp);
1286 
1287 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1288 
1289 	DPRINTF("sc = %p\n", sc);
1290 
1291 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1292 		/* The higher layer is not ready */
1293 		return;
1294 	}
1295 	ucom_start_transfers(sc);
1296 }
1297 
1298 /*------------------------------------------------------------------------*
1299  *	ucom_get_data
1300  *
1301  * Return values:
1302  * 0: No data is available.
1303  * Else: Data is available.
1304  *------------------------------------------------------------------------*/
1305 uint8_t
1306 ucom_get_data(struct ucom_softc *sc, struct usb_page_cache *pc,
1307     uint32_t offset, uint32_t len, uint32_t *actlen)
1308 {
1309 	struct usb_page_search res;
1310 	struct tty *tp = sc->sc_tty;
1311 	uint32_t cnt;
1312 	uint32_t offset_orig;
1313 
1314 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1315 
1316 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
1317 		unsigned int temp;
1318 
1319 		/* get total TX length */
1320 
1321 		temp = ucom_cons_tx_high - ucom_cons_tx_low;
1322 		temp %= UCOM_CONS_BUFSIZE;
1323 
1324 		/* limit TX length */
1325 
1326 		if (temp > (UCOM_CONS_BUFSIZE - ucom_cons_tx_low))
1327 			temp = (UCOM_CONS_BUFSIZE - ucom_cons_tx_low);
1328 
1329 		if (temp > len)
1330 			temp = len;
1331 
1332 		/* copy in data */
1333 
1334 		usbd_copy_in(pc, offset, ucom_cons_tx_buf + ucom_cons_tx_low, temp);
1335 
1336 		/* update counters */
1337 
1338 		ucom_cons_tx_low += temp;
1339 		ucom_cons_tx_low %= UCOM_CONS_BUFSIZE;
1340 
1341 		/* store actual length */
1342 
1343 		*actlen = temp;
1344 
1345 		return (temp ? 1 : 0);
1346 	}
1347 
1348 	if (tty_gone(tp) ||
1349 	    !(sc->sc_flag & UCOM_FLAG_GP_DATA)) {
1350 		actlen[0] = 0;
1351 		return (0);		/* multiport device polling */
1352 	}
1353 	offset_orig = offset;
1354 
1355 	while (len != 0) {
1356 
1357 		usbd_get_page(pc, offset, &res);
1358 
1359 		if (res.length > len) {
1360 			res.length = len;
1361 		}
1362 		/* copy data directly into USB buffer */
1363 		cnt = ttydisc_getc(tp, res.buffer, res.length);
1364 
1365 		offset += cnt;
1366 		len -= cnt;
1367 
1368 		if (cnt < res.length) {
1369 			/* end of buffer */
1370 			break;
1371 		}
1372 	}
1373 
1374 	actlen[0] = offset - offset_orig;
1375 
1376 	DPRINTF("cnt=%d\n", actlen[0]);
1377 
1378 	if (actlen[0] == 0) {
1379 		return (0);
1380 	}
1381 	return (1);
1382 }
1383 
1384 void
1385 ucom_put_data(struct ucom_softc *sc, struct usb_page_cache *pc,
1386     uint32_t offset, uint32_t len)
1387 {
1388 	struct usb_page_search res;
1389 	struct tty *tp = sc->sc_tty;
1390 	char *buf;
1391 	uint32_t cnt;
1392 
1393 	UCOM_MTX_ASSERT(sc, MA_OWNED);
1394 
1395 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
1396 		unsigned int temp;
1397 
1398 		/* get maximum RX length */
1399 
1400 		temp = (UCOM_CONS_BUFSIZE - 1) - ucom_cons_rx_high + ucom_cons_rx_low;
1401 		temp %= UCOM_CONS_BUFSIZE;
1402 
1403 		/* limit RX length */
1404 
1405 		if (temp > (UCOM_CONS_BUFSIZE - ucom_cons_rx_high))
1406 			temp = (UCOM_CONS_BUFSIZE - ucom_cons_rx_high);
1407 
1408 		if (temp > len)
1409 			temp = len;
1410 
1411 		/* copy out data */
1412 
1413 		usbd_copy_out(pc, offset, ucom_cons_rx_buf + ucom_cons_rx_high, temp);
1414 
1415 		/* update counters */
1416 
1417 		ucom_cons_rx_high += temp;
1418 		ucom_cons_rx_high %= UCOM_CONS_BUFSIZE;
1419 
1420 		return;
1421 	}
1422 
1423 	if (tty_gone(tp))
1424 		return;			/* multiport device polling */
1425 
1426 	if (len == 0)
1427 		return;			/* no data */
1428 
1429 	/* set a flag to prevent recursation ? */
1430 
1431 	while (len > 0) {
1432 
1433 		usbd_get_page(pc, offset, &res);
1434 
1435 		if (res.length > len) {
1436 			res.length = len;
1437 		}
1438 		len -= res.length;
1439 		offset += res.length;
1440 
1441 		/* pass characters to tty layer */
1442 
1443 		buf = res.buffer;
1444 		cnt = res.length;
1445 
1446 		/* first check if we can pass the buffer directly */
1447 
1448 		if (ttydisc_can_bypass(tp)) {
1449 
1450 			/* clear any jitter buffer */
1451 			sc->sc_jitterbuf_in = 0;
1452 			sc->sc_jitterbuf_out = 0;
1453 
1454 			if (ttydisc_rint_bypass(tp, buf, cnt) != cnt) {
1455 				DPRINTF("tp=%p, data lost\n", tp);
1456 			}
1457 			continue;
1458 		}
1459 		/* need to loop */
1460 
1461 		for (cnt = 0; cnt != res.length; cnt++) {
1462 			if (sc->sc_jitterbuf_in != sc->sc_jitterbuf_out ||
1463 			    ttydisc_rint(tp, buf[cnt], 0) == -1) {
1464 				uint16_t end;
1465 				uint16_t pos;
1466 
1467 				pos = sc->sc_jitterbuf_in;
1468 				end = sc->sc_jitterbuf_out +
1469 				    UCOM_JITTERBUF_SIZE - 1;
1470 				if (end >= UCOM_JITTERBUF_SIZE)
1471 					end -= UCOM_JITTERBUF_SIZE;
1472 
1473 				for (; cnt != res.length; cnt++) {
1474 					if (pos == end)
1475 						break;
1476 					sc->sc_jitterbuf[pos] = buf[cnt];
1477 					pos++;
1478 					if (pos >= UCOM_JITTERBUF_SIZE)
1479 						pos -= UCOM_JITTERBUF_SIZE;
1480 				}
1481 
1482 				sc->sc_jitterbuf_in = pos;
1483 
1484 				/* set RTS in async fashion */
1485 				if (sc->sc_flag & UCOM_FLAG_RTS_IFLOW)
1486 					ucom_rts(sc, 1);
1487 
1488 				DPRINTF("tp=%p, lost %d "
1489 				    "chars\n", tp, res.length - cnt);
1490 				break;
1491 			}
1492 		}
1493 	}
1494 	ttydisc_rint_done(tp);
1495 }
1496 
1497 static void
1498 ucom_free(void *xsc)
1499 {
1500 	struct ucom_softc *sc = xsc;
1501 
1502 	if (sc->sc_callback->ucom_free != NULL)
1503 		sc->sc_callback->ucom_free(sc);
1504 	else
1505 		ucom_unref(sc->sc_super);
1506 
1507 	mtx_lock(&ucom_mtx);
1508 	ucom_close_refs--;
1509 	mtx_unlock(&ucom_mtx);
1510 }
1511 
1512 static cn_probe_t ucom_cnprobe;
1513 static cn_init_t ucom_cninit;
1514 static cn_term_t ucom_cnterm;
1515 static cn_getc_t ucom_cngetc;
1516 static cn_putc_t ucom_cnputc;
1517 static cn_grab_t ucom_cngrab;
1518 static cn_ungrab_t ucom_cnungrab;
1519 
1520 CONSOLE_DRIVER(ucom);
1521 
1522 static void
1523 ucom_cnprobe(struct consdev  *cp)
1524 {
1525 	if (ucom_cons_unit != -1)
1526 		cp->cn_pri = CN_NORMAL;
1527 	else
1528 		cp->cn_pri = CN_DEAD;
1529 
1530 	strlcpy(cp->cn_name, "ucom", sizeof(cp->cn_name));
1531 }
1532 
1533 static void
1534 ucom_cninit(struct consdev  *cp)
1535 {
1536 }
1537 
1538 static void
1539 ucom_cnterm(struct consdev  *cp)
1540 {
1541 }
1542 
1543 static void
1544 ucom_cngrab(struct consdev *cp)
1545 {
1546 }
1547 
1548 static void
1549 ucom_cnungrab(struct consdev *cp)
1550 {
1551 }
1552 
1553 static int
1554 ucom_cngetc(struct consdev *cd)
1555 {
1556 	struct ucom_softc *sc = ucom_cons_softc;
1557 	int c;
1558 
1559 	if (sc == NULL)
1560 		return (-1);
1561 
1562 	UCOM_MTX_LOCK(sc);
1563 
1564 	if (ucom_cons_rx_low != ucom_cons_rx_high) {
1565 		c = ucom_cons_rx_buf[ucom_cons_rx_low];
1566 		ucom_cons_rx_low ++;
1567 		ucom_cons_rx_low %= UCOM_CONS_BUFSIZE;
1568 	} else {
1569 		c = -1;
1570 	}
1571 
1572 	/* start USB transfers */
1573 	ucom_outwakeup(sc->sc_tty);
1574 
1575 	UCOM_MTX_UNLOCK(sc);
1576 
1577 	/* poll if necessary */
1578 	if (kdb_active && sc->sc_callback->ucom_poll)
1579 		(sc->sc_callback->ucom_poll) (sc);
1580 
1581 	return (c);
1582 }
1583 
1584 static void
1585 ucom_cnputc(struct consdev *cd, int c)
1586 {
1587 	struct ucom_softc *sc = ucom_cons_softc;
1588 	unsigned int temp;
1589 
1590 	if (sc == NULL)
1591 		return;
1592 
1593  repeat:
1594 
1595 	UCOM_MTX_LOCK(sc);
1596 
1597 	/* compute maximum TX length */
1598 
1599 	temp = (UCOM_CONS_BUFSIZE - 1) - ucom_cons_tx_high + ucom_cons_tx_low;
1600 	temp %= UCOM_CONS_BUFSIZE;
1601 
1602 	if (temp) {
1603 		ucom_cons_tx_buf[ucom_cons_tx_high] = c;
1604 		ucom_cons_tx_high ++;
1605 		ucom_cons_tx_high %= UCOM_CONS_BUFSIZE;
1606 	}
1607 
1608 	/* start USB transfers */
1609 	ucom_outwakeup(sc->sc_tty);
1610 
1611 	UCOM_MTX_UNLOCK(sc);
1612 
1613 	/* poll if necessary */
1614 	if (kdb_active && sc->sc_callback->ucom_poll) {
1615 		(sc->sc_callback->ucom_poll) (sc);
1616 		/* simple flow control */
1617 		if (temp == 0)
1618 			goto repeat;
1619 	}
1620 }
1621 
1622 /*------------------------------------------------------------------------*
1623  *	ucom_ref
1624  *
1625  * This function will increment the super UCOM reference count.
1626  *------------------------------------------------------------------------*/
1627 void
1628 ucom_ref(struct ucom_super_softc *ssc)
1629 {
1630 	mtx_lock(&ucom_mtx);
1631 	ssc->sc_refs++;
1632 	mtx_unlock(&ucom_mtx);
1633 }
1634 
1635 /*------------------------------------------------------------------------*
1636  *	ucom_free_unit
1637  *
1638  * This function will free the super UCOM's allocated unit
1639  * number. This function can be called on a zero-initialized
1640  * structure. This function can be called multiple times.
1641  *------------------------------------------------------------------------*/
1642 static void
1643 ucom_free_unit(struct ucom_super_softc *ssc)
1644 {
1645 	if (!(ssc->sc_flag & UCOM_FLAG_FREE_UNIT))
1646 		return;
1647 
1648 	ucom_unit_free(ssc->sc_unit);
1649 
1650 	ssc->sc_flag &= ~UCOM_FLAG_FREE_UNIT;
1651 }
1652 
1653 /*------------------------------------------------------------------------*
1654  *	ucom_unref
1655  *
1656  * This function will decrement the super UCOM reference count.
1657  *
1658  * Return values:
1659  * 0: UCOM structures are still referenced.
1660  * Else: UCOM structures are no longer referenced.
1661  *------------------------------------------------------------------------*/
1662 int
1663 ucom_unref(struct ucom_super_softc *ssc)
1664 {
1665 	int retval;
1666 
1667 	mtx_lock(&ucom_mtx);
1668 	retval = (ssc->sc_refs < 2);
1669 	ssc->sc_refs--;
1670 	mtx_unlock(&ucom_mtx);
1671 
1672 	if (retval)
1673 		ucom_free_unit(ssc);
1674 
1675 	return (retval);
1676 }
1677 
1678 #if defined(GDB)
1679 
1680 #include <gdb/gdb.h>
1681 
1682 static gdb_probe_f ucom_gdbprobe;
1683 static gdb_init_f ucom_gdbinit;
1684 static gdb_term_f ucom_gdbterm;
1685 static gdb_getc_f ucom_gdbgetc;
1686 static gdb_putc_f ucom_gdbputc;
1687 
1688 GDB_DBGPORT(sio, ucom_gdbprobe, ucom_gdbinit, ucom_gdbterm, ucom_gdbgetc, ucom_gdbputc);
1689 
1690 static int
1691 ucom_gdbprobe(void)
1692 {
1693 	return ((ucom_cons_softc != NULL) ? 0 : -1);
1694 }
1695 
1696 static void
1697 ucom_gdbinit(void)
1698 {
1699 }
1700 
1701 static void
1702 ucom_gdbterm(void)
1703 {
1704 }
1705 
1706 static void
1707 ucom_gdbputc(int c)
1708 {
1709         ucom_cnputc(NULL, c);
1710 }
1711 
1712 static int
1713 ucom_gdbgetc(void)
1714 {
1715         return (ucom_cngetc(NULL));
1716 }
1717 
1718 #endif
1719