xref: /freebsd/sys/dev/usb/serial/usb_serial.c (revision aa0a1e58)
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  * 3. All advertising materials mentioning features or use of this software
50  *    must display the following acknowledgement:
51  *        This product includes software developed by the NetBSD
52  *        Foundation, Inc. and its contributors.
53  * 4. Neither the name of The NetBSD Foundation nor the names of its
54  *    contributors may be used to endorse or promote products derived
55  *    from this software without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
58  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
59  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
60  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
61  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
62  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
63  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
64  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
65  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
66  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
67  * POSSIBILITY OF SUCH DAMAGE.
68  */
69 
70 #include <sys/stdint.h>
71 #include <sys/stddef.h>
72 #include <sys/param.h>
73 #include <sys/queue.h>
74 #include <sys/types.h>
75 #include <sys/systm.h>
76 #include <sys/kernel.h>
77 #include <sys/bus.h>
78 #include <sys/module.h>
79 #include <sys/lock.h>
80 #include <sys/mutex.h>
81 #include <sys/condvar.h>
82 #include <sys/sysctl.h>
83 #include <sys/sx.h>
84 #include <sys/unistd.h>
85 #include <sys/callout.h>
86 #include <sys/malloc.h>
87 #include <sys/priv.h>
88 #include <sys/cons.h>
89 #include <sys/kdb.h>
90 
91 #include <dev/usb/usb.h>
92 #include <dev/usb/usbdi.h>
93 #include <dev/usb/usbdi_util.h>
94 
95 #define	USB_DEBUG_VAR ucom_debug
96 #include <dev/usb/usb_debug.h>
97 #include <dev/usb/usb_busdma.h>
98 #include <dev/usb/usb_process.h>
99 
100 #include <dev/usb/serial/usb_serial.h>
101 
102 #include "opt_gdb.h"
103 
104 SYSCTL_NODE(_hw_usb, OID_AUTO, ucom, CTLFLAG_RW, 0, "USB ucom");
105 
106 #ifdef USB_DEBUG
107 static int ucom_debug = 0;
108 
109 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, debug, CTLFLAG_RW,
110     &ucom_debug, 0, "ucom debug level");
111 #endif
112 
113 #define	UCOM_CONS_BUFSIZE 1024
114 
115 static uint8_t ucom_cons_rx_buf[UCOM_CONS_BUFSIZE];
116 static uint8_t ucom_cons_tx_buf[UCOM_CONS_BUFSIZE];
117 
118 static unsigned int ucom_cons_rx_low = 0;
119 static unsigned int ucom_cons_rx_high = 0;
120 
121 static unsigned int ucom_cons_tx_low = 0;
122 static unsigned int ucom_cons_tx_high = 0;
123 
124 static int ucom_cons_unit = -1;
125 static int ucom_cons_subunit = 0;
126 static int ucom_cons_baud = 9600;
127 static struct ucom_softc *ucom_cons_softc = NULL;
128 
129 TUNABLE_INT("hw.usb.ucom.cons_unit", &ucom_cons_unit);
130 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_unit, CTLFLAG_RW,
131     &ucom_cons_unit, 0, "console unit number");
132 TUNABLE_INT("hw.usb.ucom.cons_subunit", &ucom_cons_subunit);
133 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_subunit, CTLFLAG_RW,
134     &ucom_cons_subunit, 0, "console subunit number");
135 TUNABLE_INT("hw.usb.ucom.cons_baud", &ucom_cons_baud);
136 SYSCTL_INT(_hw_usb_ucom, OID_AUTO, cons_baud, CTLFLAG_RW,
137     &ucom_cons_baud, 0, "console baud rate");
138 
139 static usb_proc_callback_t ucom_cfg_start_transfers;
140 static usb_proc_callback_t ucom_cfg_open;
141 static usb_proc_callback_t ucom_cfg_close;
142 static usb_proc_callback_t ucom_cfg_line_state;
143 static usb_proc_callback_t ucom_cfg_status_change;
144 static usb_proc_callback_t ucom_cfg_param;
145 
146 static int	ucom_unit_alloc(void);
147 static void	ucom_unit_free(int);
148 static int	ucom_attach_tty(struct ucom_super_softc *, struct ucom_softc *);
149 static void	ucom_detach_tty(struct ucom_softc *);
150 static void	ucom_queue_command(struct ucom_softc *,
151 		    usb_proc_callback_t *, struct termios *pt,
152 		    struct usb_proc_msg *t0, struct usb_proc_msg *t1);
153 static void	ucom_shutdown(struct ucom_softc *);
154 static void	ucom_ring(struct ucom_softc *, uint8_t);
155 static void	ucom_break(struct ucom_softc *, uint8_t);
156 static void	ucom_dtr(struct ucom_softc *, uint8_t);
157 static void	ucom_rts(struct ucom_softc *, uint8_t);
158 
159 static tsw_open_t ucom_open;
160 static tsw_close_t ucom_close;
161 static tsw_ioctl_t ucom_ioctl;
162 static tsw_modem_t ucom_modem;
163 static tsw_param_t ucom_param;
164 static tsw_outwakeup_t ucom_outwakeup;
165 static tsw_free_t ucom_free;
166 
167 static struct ttydevsw ucom_class = {
168 	.tsw_flags = TF_INITLOCK | TF_CALLOUT,
169 	.tsw_open = ucom_open,
170 	.tsw_close = ucom_close,
171 	.tsw_outwakeup = ucom_outwakeup,
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	/* limits size of ucom_bitmap */
182 
183 static uint8_t ucom_bitmap[(UCOM_UNIT_MAX + 7) / 8];
184 static struct mtx ucom_bitmap_mtx;
185 MTX_SYSINIT(ucom_bitmap_mtx, &ucom_bitmap_mtx, "ucom bitmap", MTX_DEF);
186 
187 #define UCOM_TTY_PREFIX		"U"
188 
189 /*
190  * Mark a unit number (the X in cuaUX) as in use.
191  *
192  * Note that devices using a different naming scheme (see ucom_tty_name()
193  * callback) still use this unit allocation.
194  */
195 static int
196 ucom_unit_alloc(void)
197 {
198 	int unit;
199 
200 	mtx_lock(&ucom_bitmap_mtx);
201 
202 	for (unit = 0; unit < UCOM_UNIT_MAX; unit++) {
203 		if ((ucom_bitmap[unit / 8] & (1 << (unit % 8))) == 0) {
204 			ucom_bitmap[unit / 8] |= (1 << (unit % 8));
205 			break;
206 		}
207 	}
208 
209 	mtx_unlock(&ucom_bitmap_mtx);
210 
211 	if (unit == UCOM_UNIT_MAX)
212 		return -1;
213 	else
214 		return unit;
215 }
216 
217 /*
218  * Mark the unit number as not in use.
219  */
220 static void
221 ucom_unit_free(int unit)
222 {
223 	mtx_lock(&ucom_bitmap_mtx);
224 
225 	ucom_bitmap[unit / 8] &= ~(1 << (unit % 8));
226 
227 	mtx_unlock(&ucom_bitmap_mtx);
228 }
229 
230 /*
231  * Setup a group of one or more serial ports.
232  *
233  * The mutex pointed to by "mtx" is applied before all
234  * callbacks are called back. Also "mtx" must be applied
235  * before calling into the ucom-layer!
236  */
237 int
238 ucom_attach(struct ucom_super_softc *ssc, struct ucom_softc *sc,
239     uint32_t subunits, void *parent,
240     const struct ucom_callback *callback, struct mtx *mtx)
241 {
242 	uint32_t subunit;
243 	int error = 0;
244 
245 	if ((sc == NULL) ||
246 	    (subunits == 0) ||
247 	    (callback == NULL)) {
248 		return (EINVAL);
249 	}
250 
251 	ssc->sc_unit = ucom_unit_alloc();
252 	if (ssc->sc_unit == -1)
253 		return (ENOMEM);
254 
255 	error = usb_proc_create(&ssc->sc_tq, mtx, "ucom", USB_PRI_MED);
256 	if (error) {
257 		ucom_unit_free(ssc->sc_unit);
258 		return (error);
259 	}
260 	ssc->sc_subunits = subunits;
261 
262 	for (subunit = 0; subunit < ssc->sc_subunits; subunit++) {
263 		sc[subunit].sc_subunit = subunit;
264 		sc[subunit].sc_super = ssc;
265 		sc[subunit].sc_mtx = mtx;
266 		sc[subunit].sc_parent = parent;
267 		sc[subunit].sc_callback = callback;
268 
269 		error = ucom_attach_tty(ssc, &sc[subunit]);
270 		if (error) {
271 			ucom_detach(ssc, &sc[0]);
272 			return (error);
273 		}
274 		sc[subunit].sc_flag |= UCOM_FLAG_ATTACHED;
275 	}
276 
277 	DPRINTF("tp = %p, unit = %d, subunits = %d\n",
278 		sc->sc_tty, ssc->sc_unit, ssc->sc_subunits);
279 
280 	return (0);
281 }
282 
283 /*
284  * NOTE: the following function will do nothing if
285  * the structure pointed to by "ssc" and "sc" is zero.
286  */
287 void
288 ucom_detach(struct ucom_super_softc *ssc, struct ucom_softc *sc)
289 {
290 	uint32_t subunit;
291 
292 	usb_proc_drain(&ssc->sc_tq);
293 
294 	for (subunit = 0; subunit < ssc->sc_subunits; subunit++) {
295 		if (sc[subunit].sc_flag & UCOM_FLAG_ATTACHED) {
296 
297 			ucom_detach_tty(&sc[subunit]);
298 
299 			/* avoid duplicate detach */
300 			sc[subunit].sc_flag &= ~UCOM_FLAG_ATTACHED;
301 		}
302 	}
303 	ucom_unit_free(ssc->sc_unit);
304 	usb_proc_free(&ssc->sc_tq);
305 }
306 
307 static int
308 ucom_attach_tty(struct ucom_super_softc *ssc, struct ucom_softc *sc)
309 {
310 	struct tty *tp;
311 	char buf[32];			/* temporary TTY device name buffer */
312 
313 	tp = tty_alloc_mutex(&ucom_class, sc, sc->sc_mtx);
314 	if (tp == NULL)
315 		return (ENOMEM);
316 
317 	/* Check if the client has a custom TTY name */
318 	buf[0] = '\0';
319 	if (sc->sc_callback->ucom_tty_name) {
320 		sc->sc_callback->ucom_tty_name(sc, buf,
321 		    sizeof(buf), ssc->sc_unit, sc->sc_subunit);
322 	}
323 	if (buf[0] == 0) {
324 		/* Use default TTY name */
325 		if (ssc->sc_subunits > 1) {
326 			/* multiple modems in one */
327 			snprintf(buf, sizeof(buf), UCOM_TTY_PREFIX "%u.%u",
328 			    ssc->sc_unit, sc->sc_subunit);
329 		} else {
330 			/* single modem */
331 			snprintf(buf, sizeof(buf), UCOM_TTY_PREFIX "%u",
332 			    ssc->sc_unit);
333 		}
334 	}
335 	tty_makedev(tp, NULL, "%s", buf);
336 
337 	sc->sc_tty = tp;
338 
339 	DPRINTF("ttycreate: %s\n", buf);
340 	cv_init(&sc->sc_cv, "ucom");
341 
342 	/* Check if this device should be a console */
343 	if ((ucom_cons_softc == NULL) &&
344 	    (ssc->sc_unit == ucom_cons_unit) &&
345 	    (sc->sc_subunit == ucom_cons_subunit)) {
346 		struct termios t;
347 
348 		DPRINTF("unit %d subunit %d is console", ssc->sc_unit, sc->sc_subunit);
349 
350 		ucom_cons_softc = sc;
351 
352 		memset(&t, 0, sizeof(t));
353 		t.c_ispeed = ucom_cons_baud;
354 		t.c_ospeed = t.c_ispeed;
355 		t.c_cflag = CS8;
356 
357 		mtx_lock(ucom_cons_softc->sc_mtx);
358 		ucom_cons_rx_low = 0;
359 		ucom_cons_rx_high = 0;
360 		ucom_cons_tx_low = 0;
361 		ucom_cons_tx_high = 0;
362 		sc->sc_flag |= UCOM_FLAG_CONSOLE;
363 		ucom_open(ucom_cons_softc->sc_tty);
364 		ucom_param(ucom_cons_softc->sc_tty, &t);
365 		mtx_unlock(ucom_cons_softc->sc_mtx);
366 	}
367 
368 	return (0);
369 }
370 
371 static void
372 ucom_detach_tty(struct ucom_softc *sc)
373 {
374 	struct tty *tp = sc->sc_tty;
375 
376 	DPRINTF("sc = %p, tp = %p\n", sc, sc->sc_tty);
377 
378 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
379 		mtx_lock(ucom_cons_softc->sc_mtx);
380 		ucom_close(ucom_cons_softc->sc_tty);
381 		sc->sc_flag &= ~UCOM_FLAG_CONSOLE;
382 		mtx_unlock(ucom_cons_softc->sc_mtx);
383 		ucom_cons_softc = NULL;
384 	}
385 
386 	/* the config thread has been stopped when we get here */
387 
388 	mtx_lock(sc->sc_mtx);
389 	sc->sc_flag |= UCOM_FLAG_GONE;
390 	sc->sc_flag &= ~(UCOM_FLAG_HL_READY | UCOM_FLAG_LL_READY);
391 	mtx_unlock(sc->sc_mtx);
392 	if (tp) {
393 		tty_lock(tp);
394 
395 		ucom_close(tp);	/* close, if any */
396 
397 		tty_rel_gone(tp);
398 
399 		mtx_lock(sc->sc_mtx);
400 		/* Wait for the callback after the TTY is torn down */
401 		while (sc->sc_ttyfreed == 0)
402 			cv_wait(&sc->sc_cv, sc->sc_mtx);
403 		/*
404 		 * make sure that read and write transfers are stopped
405 		 */
406 		if (sc->sc_callback->ucom_stop_read) {
407 			(sc->sc_callback->ucom_stop_read) (sc);
408 		}
409 		if (sc->sc_callback->ucom_stop_write) {
410 			(sc->sc_callback->ucom_stop_write) (sc);
411 		}
412 		mtx_unlock(sc->sc_mtx);
413 	}
414 	cv_destroy(&sc->sc_cv);
415 }
416 
417 void
418 ucom_set_pnpinfo_usb(struct ucom_super_softc *ssc, device_t dev)
419 {
420     char buf[64];
421     uint8_t iface_index;
422     struct usb_attach_arg *uaa;
423 
424     snprintf(buf, sizeof(buf), "ttyname=%s%d ttyports=%d",
425 	     UCOM_TTY_PREFIX, ssc->sc_unit, ssc->sc_subunits);
426 
427     /* Store the PNP info in the first interface for the dev */
428     uaa = device_get_ivars(dev);
429     iface_index = uaa->info.bIfaceIndex;
430 
431     if (usbd_set_pnpinfo(uaa->device, iface_index, buf) != 0)
432 	device_printf(dev, "Could not set PNP info\n");
433 }
434 
435 static void
436 ucom_queue_command(struct ucom_softc *sc,
437     usb_proc_callback_t *fn, struct termios *pt,
438     struct usb_proc_msg *t0, struct usb_proc_msg *t1)
439 {
440 	struct ucom_super_softc *ssc = sc->sc_super;
441 	struct ucom_param_task *task;
442 
443 	mtx_assert(sc->sc_mtx, MA_OWNED);
444 
445 	if (usb_proc_is_gone(&ssc->sc_tq)) {
446 		DPRINTF("proc is gone\n");
447 		return;         /* nothing to do */
448 	}
449 	/*
450 	 * NOTE: The task cannot get executed before we drop the
451 	 * "sc_mtx" mutex. It is safe to update fields in the message
452 	 * structure after that the message got queued.
453 	 */
454 	task = (struct ucom_param_task *)
455 	  usb_proc_msignal(&ssc->sc_tq, t0, t1);
456 
457 	/* Setup callback and softc pointers */
458 	task->hdr.pm_callback = fn;
459 	task->sc = sc;
460 
461 	/*
462 	 * Make a copy of the termios. This field is only present if
463 	 * the "pt" field is not NULL.
464 	 */
465 	if (pt != NULL)
466 		task->termios_copy = *pt;
467 
468 	/*
469 	 * Closing the device should be synchronous.
470 	 */
471 	if (fn == ucom_cfg_close)
472 		usb_proc_mwait(&ssc->sc_tq, t0, t1);
473 
474 	/*
475 	 * In case of multiple configure requests,
476 	 * keep track of the last one!
477 	 */
478 	if (fn == ucom_cfg_start_transfers)
479 		sc->sc_last_start_xfer = &task->hdr;
480 }
481 
482 static void
483 ucom_shutdown(struct ucom_softc *sc)
484 {
485 	struct tty *tp = sc->sc_tty;
486 
487 	mtx_assert(sc->sc_mtx, MA_OWNED);
488 
489 	DPRINTF("\n");
490 
491 	/*
492 	 * Hang up if necessary:
493 	 */
494 	if (tp->t_termios.c_cflag & HUPCL) {
495 		ucom_modem(tp, 0, SER_DTR);
496 	}
497 }
498 
499 /*
500  * Return values:
501  *    0: normal
502  * else: taskqueue is draining or gone
503  */
504 uint8_t
505 ucom_cfg_is_gone(struct ucom_softc *sc)
506 {
507 	struct ucom_super_softc *ssc = sc->sc_super;
508 
509 	return (usb_proc_is_gone(&ssc->sc_tq));
510 }
511 
512 static void
513 ucom_cfg_start_transfers(struct usb_proc_msg *_task)
514 {
515 	struct ucom_cfg_task *task =
516 	    (struct ucom_cfg_task *)_task;
517 	struct ucom_softc *sc = task->sc;
518 
519 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
520 		return;
521 	}
522 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
523 		/* TTY device closed */
524 		return;
525 	}
526 
527 	if (_task == sc->sc_last_start_xfer)
528 		sc->sc_flag |= UCOM_FLAG_GP_DATA;
529 
530 	if (sc->sc_callback->ucom_start_read) {
531 		(sc->sc_callback->ucom_start_read) (sc);
532 	}
533 	if (sc->sc_callback->ucom_start_write) {
534 		(sc->sc_callback->ucom_start_write) (sc);
535 	}
536 }
537 
538 static void
539 ucom_start_transfers(struct ucom_softc *sc)
540 {
541 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
542 		return;
543 	}
544 	/*
545 	 * Make sure that data transfers are started in both
546 	 * directions:
547 	 */
548 	if (sc->sc_callback->ucom_start_read) {
549 		(sc->sc_callback->ucom_start_read) (sc);
550 	}
551 	if (sc->sc_callback->ucom_start_write) {
552 		(sc->sc_callback->ucom_start_write) (sc);
553 	}
554 }
555 
556 static void
557 ucom_cfg_open(struct usb_proc_msg *_task)
558 {
559 	struct ucom_cfg_task *task =
560 	    (struct ucom_cfg_task *)_task;
561 	struct ucom_softc *sc = task->sc;
562 
563 	DPRINTF("\n");
564 
565 	if (sc->sc_flag & UCOM_FLAG_LL_READY) {
566 
567 		/* already opened */
568 
569 	} else {
570 
571 		sc->sc_flag |= UCOM_FLAG_LL_READY;
572 
573 		if (sc->sc_callback->ucom_cfg_open) {
574 			(sc->sc_callback->ucom_cfg_open) (sc);
575 
576 			/* wait a little */
577 			usb_pause_mtx(sc->sc_mtx, hz / 10);
578 		}
579 	}
580 }
581 
582 static int
583 ucom_open(struct tty *tp)
584 {
585 	struct ucom_softc *sc = tty_softc(tp);
586 	int error;
587 
588 	mtx_assert(sc->sc_mtx, MA_OWNED);
589 
590 	if (sc->sc_flag & UCOM_FLAG_GONE) {
591 		return (ENXIO);
592 	}
593 	if (sc->sc_flag & UCOM_FLAG_HL_READY) {
594 		/* already opened */
595 		return (0);
596 	}
597 	DPRINTF("tp = %p\n", tp);
598 
599 	if (sc->sc_callback->ucom_pre_open) {
600 		/*
601 		 * give the lower layer a chance to disallow TTY open, for
602 		 * example if the device is not present:
603 		 */
604 		error = (sc->sc_callback->ucom_pre_open) (sc);
605 		if (error) {
606 			return (error);
607 		}
608 	}
609 	sc->sc_flag |= UCOM_FLAG_HL_READY;
610 
611 	/* Disable transfers */
612 	sc->sc_flag &= ~UCOM_FLAG_GP_DATA;
613 
614 	sc->sc_lsr = 0;
615 	sc->sc_msr = 0;
616 	sc->sc_mcr = 0;
617 
618 	/* reset programmed line state */
619 	sc->sc_pls_curr = 0;
620 	sc->sc_pls_set = 0;
621 	sc->sc_pls_clr = 0;
622 
623 	ucom_queue_command(sc, ucom_cfg_open, NULL,
624 	    &sc->sc_open_task[0].hdr,
625 	    &sc->sc_open_task[1].hdr);
626 
627 	/* Queue transfer enable command last */
628 	ucom_queue_command(sc, ucom_cfg_start_transfers, NULL,
629 	    &sc->sc_start_task[0].hdr,
630 	    &sc->sc_start_task[1].hdr);
631 
632 	ucom_modem(tp, SER_DTR | SER_RTS, 0);
633 
634 	ucom_ring(sc, 0);
635 
636 	ucom_break(sc, 0);
637 
638 	ucom_status_change(sc);
639 
640 	return (0);
641 }
642 
643 static void
644 ucom_cfg_close(struct usb_proc_msg *_task)
645 {
646 	struct ucom_cfg_task *task =
647 	    (struct ucom_cfg_task *)_task;
648 	struct ucom_softc *sc = task->sc;
649 
650 	DPRINTF("\n");
651 
652 	if (sc->sc_flag & UCOM_FLAG_LL_READY) {
653 		sc->sc_flag &= ~UCOM_FLAG_LL_READY;
654 		if (sc->sc_callback->ucom_cfg_close)
655 			(sc->sc_callback->ucom_cfg_close) (sc);
656 	} else {
657 		/* already closed */
658 	}
659 }
660 
661 static void
662 ucom_close(struct tty *tp)
663 {
664 	struct ucom_softc *sc = tty_softc(tp);
665 
666 	mtx_assert(sc->sc_mtx, MA_OWNED);
667 
668 	DPRINTF("tp=%p\n", tp);
669 
670 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
671 		DPRINTF("tp=%p already closed\n", tp);
672 		return;
673 	}
674 	ucom_shutdown(sc);
675 
676 	ucom_queue_command(sc, ucom_cfg_close, NULL,
677 	    &sc->sc_close_task[0].hdr,
678 	    &sc->sc_close_task[1].hdr);
679 
680 	sc->sc_flag &= ~(UCOM_FLAG_HL_READY | UCOM_FLAG_RTS_IFLOW);
681 
682 	if (sc->sc_callback->ucom_stop_read) {
683 		(sc->sc_callback->ucom_stop_read) (sc);
684 	}
685 }
686 
687 static int
688 ucom_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
689 {
690 	struct ucom_softc *sc = tty_softc(tp);
691 	int error;
692 
693 	mtx_assert(sc->sc_mtx, MA_OWNED);
694 
695 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
696 		return (EIO);
697 	}
698 	DPRINTF("cmd = 0x%08lx\n", cmd);
699 
700 	switch (cmd) {
701 #if 0
702 	case TIOCSRING:
703 		ucom_ring(sc, 1);
704 		error = 0;
705 		break;
706 	case TIOCCRING:
707 		ucom_ring(sc, 0);
708 		error = 0;
709 		break;
710 #endif
711 	case TIOCSBRK:
712 		ucom_break(sc, 1);
713 		error = 0;
714 		break;
715 	case TIOCCBRK:
716 		ucom_break(sc, 0);
717 		error = 0;
718 		break;
719 	default:
720 		if (sc->sc_callback->ucom_ioctl) {
721 			error = (sc->sc_callback->ucom_ioctl)
722 			    (sc, cmd, data, 0, td);
723 		} else {
724 			error = ENOIOCTL;
725 		}
726 		break;
727 	}
728 	return (error);
729 }
730 
731 static int
732 ucom_modem(struct tty *tp, int sigon, int sigoff)
733 {
734 	struct ucom_softc *sc = tty_softc(tp);
735 	uint8_t onoff;
736 
737 	mtx_assert(sc->sc_mtx, MA_OWNED);
738 
739 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
740 		return (0);
741 	}
742 	if ((sigon == 0) && (sigoff == 0)) {
743 
744 		if (sc->sc_mcr & SER_DTR) {
745 			sigon |= SER_DTR;
746 		}
747 		if (sc->sc_mcr & SER_RTS) {
748 			sigon |= SER_RTS;
749 		}
750 		if (sc->sc_msr & SER_CTS) {
751 			sigon |= SER_CTS;
752 		}
753 		if (sc->sc_msr & SER_DCD) {
754 			sigon |= SER_DCD;
755 		}
756 		if (sc->sc_msr & SER_DSR) {
757 			sigon |= SER_DSR;
758 		}
759 		if (sc->sc_msr & SER_RI) {
760 			sigon |= SER_RI;
761 		}
762 		return (sigon);
763 	}
764 	if (sigon & SER_DTR) {
765 		sc->sc_mcr |= SER_DTR;
766 	}
767 	if (sigoff & SER_DTR) {
768 		sc->sc_mcr &= ~SER_DTR;
769 	}
770 	if (sigon & SER_RTS) {
771 		sc->sc_mcr |= SER_RTS;
772 	}
773 	if (sigoff & SER_RTS) {
774 		sc->sc_mcr &= ~SER_RTS;
775 	}
776 	onoff = (sc->sc_mcr & SER_DTR) ? 1 : 0;
777 	ucom_dtr(sc, onoff);
778 
779 	onoff = (sc->sc_mcr & SER_RTS) ? 1 : 0;
780 	ucom_rts(sc, onoff);
781 
782 	return (0);
783 }
784 
785 static void
786 ucom_cfg_line_state(struct usb_proc_msg *_task)
787 {
788 	struct ucom_cfg_task *task =
789 	    (struct ucom_cfg_task *)_task;
790 	struct ucom_softc *sc = task->sc;
791 	uint8_t notch_bits;
792 	uint8_t any_bits;
793 	uint8_t prev_value;
794 	uint8_t last_value;
795 	uint8_t mask;
796 
797 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
798 		return;
799 	}
800 
801 	mask = 0;
802 	/* compute callback mask */
803 	if (sc->sc_callback->ucom_cfg_set_dtr)
804 		mask |= UCOM_LS_DTR;
805 	if (sc->sc_callback->ucom_cfg_set_rts)
806 		mask |= UCOM_LS_RTS;
807 	if (sc->sc_callback->ucom_cfg_set_break)
808 		mask |= UCOM_LS_BREAK;
809 	if (sc->sc_callback->ucom_cfg_set_ring)
810 		mask |= UCOM_LS_RING;
811 
812 	/* compute the bits we are to program */
813 	notch_bits = (sc->sc_pls_set & sc->sc_pls_clr) & mask;
814 	any_bits = (sc->sc_pls_set | sc->sc_pls_clr) & mask;
815 	prev_value = sc->sc_pls_curr ^ notch_bits;
816 	last_value = sc->sc_pls_curr;
817 
818 	/* reset programmed line state */
819 	sc->sc_pls_curr = 0;
820 	sc->sc_pls_set = 0;
821 	sc->sc_pls_clr = 0;
822 
823 	/* ensure that we don't loose any levels */
824 	if (notch_bits & UCOM_LS_DTR)
825 		sc->sc_callback->ucom_cfg_set_dtr(sc,
826 		    (prev_value & UCOM_LS_DTR) ? 1 : 0);
827 	if (notch_bits & UCOM_LS_RTS)
828 		sc->sc_callback->ucom_cfg_set_rts(sc,
829 		    (prev_value & UCOM_LS_RTS) ? 1 : 0);
830 	if (notch_bits & UCOM_LS_BREAK)
831 		sc->sc_callback->ucom_cfg_set_break(sc,
832 		    (prev_value & UCOM_LS_BREAK) ? 1 : 0);
833 	if (notch_bits & UCOM_LS_RING)
834 		sc->sc_callback->ucom_cfg_set_ring(sc,
835 		    (prev_value & UCOM_LS_RING) ? 1 : 0);
836 
837 	/* set last value */
838 	if (any_bits & UCOM_LS_DTR)
839 		sc->sc_callback->ucom_cfg_set_dtr(sc,
840 		    (last_value & UCOM_LS_DTR) ? 1 : 0);
841 	if (any_bits & UCOM_LS_RTS)
842 		sc->sc_callback->ucom_cfg_set_rts(sc,
843 		    (last_value & UCOM_LS_RTS) ? 1 : 0);
844 	if (any_bits & UCOM_LS_BREAK)
845 		sc->sc_callback->ucom_cfg_set_break(sc,
846 		    (last_value & UCOM_LS_BREAK) ? 1 : 0);
847 	if (any_bits & UCOM_LS_RING)
848 		sc->sc_callback->ucom_cfg_set_ring(sc,
849 		    (last_value & UCOM_LS_RING) ? 1 : 0);
850 }
851 
852 static void
853 ucom_line_state(struct ucom_softc *sc,
854     uint8_t set_bits, uint8_t clear_bits)
855 {
856 	mtx_assert(sc->sc_mtx, MA_OWNED);
857 
858 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
859 		return;
860 	}
861 
862 	DPRINTF("on=0x%02x, off=0x%02x\n", set_bits, clear_bits);
863 
864 	/* update current programmed line state */
865 	sc->sc_pls_curr |= set_bits;
866 	sc->sc_pls_curr &= ~clear_bits;
867 	sc->sc_pls_set |= set_bits;
868 	sc->sc_pls_clr |= clear_bits;
869 
870 	/* defer driver programming */
871 	ucom_queue_command(sc, ucom_cfg_line_state, NULL,
872 	    &sc->sc_line_state_task[0].hdr,
873 	    &sc->sc_line_state_task[1].hdr);
874 }
875 
876 static void
877 ucom_ring(struct ucom_softc *sc, uint8_t onoff)
878 {
879 	DPRINTF("onoff = %d\n", onoff);
880 
881 	if (onoff)
882 		ucom_line_state(sc, UCOM_LS_RING, 0);
883 	else
884 		ucom_line_state(sc, 0, UCOM_LS_RING);
885 }
886 
887 static void
888 ucom_break(struct ucom_softc *sc, uint8_t onoff)
889 {
890 	DPRINTF("onoff = %d\n", onoff);
891 
892 	if (onoff)
893 		ucom_line_state(sc, UCOM_LS_BREAK, 0);
894 	else
895 		ucom_line_state(sc, 0, UCOM_LS_BREAK);
896 }
897 
898 static void
899 ucom_dtr(struct ucom_softc *sc, uint8_t onoff)
900 {
901 	DPRINTF("onoff = %d\n", onoff);
902 
903 	if (onoff)
904 		ucom_line_state(sc, UCOM_LS_DTR, 0);
905 	else
906 		ucom_line_state(sc, 0, UCOM_LS_DTR);
907 }
908 
909 static void
910 ucom_rts(struct ucom_softc *sc, uint8_t onoff)
911 {
912 	DPRINTF("onoff = %d\n", onoff);
913 
914 	if (onoff)
915 		ucom_line_state(sc, UCOM_LS_RTS, 0);
916 	else
917 		ucom_line_state(sc, 0, UCOM_LS_RTS);
918 }
919 
920 static void
921 ucom_cfg_status_change(struct usb_proc_msg *_task)
922 {
923 	struct ucom_cfg_task *task =
924 	    (struct ucom_cfg_task *)_task;
925 	struct ucom_softc *sc = task->sc;
926 	struct tty *tp;
927 	uint8_t new_msr;
928 	uint8_t new_lsr;
929 	uint8_t onoff;
930 	uint8_t lsr_delta;
931 
932 	tp = sc->sc_tty;
933 
934 	mtx_assert(sc->sc_mtx, MA_OWNED);
935 
936 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
937 		return;
938 	}
939 	if (sc->sc_callback->ucom_cfg_get_status == NULL) {
940 		return;
941 	}
942 	/* get status */
943 
944 	new_msr = 0;
945 	new_lsr = 0;
946 
947 	(sc->sc_callback->ucom_cfg_get_status) (sc, &new_lsr, &new_msr);
948 
949 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
950 		/* TTY device closed */
951 		return;
952 	}
953 	onoff = ((sc->sc_msr ^ new_msr) & SER_DCD);
954 	lsr_delta = (sc->sc_lsr ^ new_lsr);
955 
956 	sc->sc_msr = new_msr;
957 	sc->sc_lsr = new_lsr;
958 
959 	if (onoff) {
960 
961 		onoff = (sc->sc_msr & SER_DCD) ? 1 : 0;
962 
963 		DPRINTF("DCD changed to %d\n", onoff);
964 
965 		ttydisc_modem(tp, onoff);
966 	}
967 
968 	if ((lsr_delta & ULSR_BI) && (sc->sc_lsr & ULSR_BI)) {
969 
970 		DPRINTF("BREAK detected\n");
971 
972 		ttydisc_rint(tp, 0, TRE_BREAK);
973 		ttydisc_rint_done(tp);
974 	}
975 
976 	if ((lsr_delta & ULSR_FE) && (sc->sc_lsr & ULSR_FE)) {
977 
978 		DPRINTF("Frame error detected\n");
979 
980 		ttydisc_rint(tp, 0, TRE_FRAMING);
981 		ttydisc_rint_done(tp);
982 	}
983 
984 	if ((lsr_delta & ULSR_PE) && (sc->sc_lsr & ULSR_PE)) {
985 
986 		DPRINTF("Parity error detected\n");
987 
988 		ttydisc_rint(tp, 0, TRE_PARITY);
989 		ttydisc_rint_done(tp);
990 	}
991 }
992 
993 void
994 ucom_status_change(struct ucom_softc *sc)
995 {
996 	mtx_assert(sc->sc_mtx, MA_OWNED);
997 
998 	if (sc->sc_flag & UCOM_FLAG_CONSOLE)
999 		return;		/* not supported */
1000 
1001 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1002 		return;
1003 	}
1004 	DPRINTF("\n");
1005 
1006 	ucom_queue_command(sc, ucom_cfg_status_change, NULL,
1007 	    &sc->sc_status_task[0].hdr,
1008 	    &sc->sc_status_task[1].hdr);
1009 }
1010 
1011 static void
1012 ucom_cfg_param(struct usb_proc_msg *_task)
1013 {
1014 	struct ucom_param_task *task =
1015 	    (struct ucom_param_task *)_task;
1016 	struct ucom_softc *sc = task->sc;
1017 
1018 	if (!(sc->sc_flag & UCOM_FLAG_LL_READY)) {
1019 		return;
1020 	}
1021 	if (sc->sc_callback->ucom_cfg_param == NULL) {
1022 		return;
1023 	}
1024 
1025 	(sc->sc_callback->ucom_cfg_param) (sc, &task->termios_copy);
1026 
1027 	/* wait a little */
1028 	usb_pause_mtx(sc->sc_mtx, hz / 10);
1029 }
1030 
1031 static int
1032 ucom_param(struct tty *tp, struct termios *t)
1033 {
1034 	struct ucom_softc *sc = tty_softc(tp);
1035 	uint8_t opened;
1036 	int error;
1037 
1038 	mtx_assert(sc->sc_mtx, MA_OWNED);
1039 
1040 	opened = 0;
1041 	error = 0;
1042 
1043 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1044 
1045 		/* XXX the TTY layer should call "open()" first! */
1046 
1047 		error = ucom_open(tp);
1048 		if (error) {
1049 			goto done;
1050 		}
1051 		opened = 1;
1052 	}
1053 	DPRINTF("sc = %p\n", sc);
1054 
1055 	/* Check requested parameters. */
1056 	if (t->c_ospeed < 0) {
1057 		DPRINTF("negative ospeed\n");
1058 		error = EINVAL;
1059 		goto done;
1060 	}
1061 	if (t->c_ispeed && (t->c_ispeed != t->c_ospeed)) {
1062 		DPRINTF("mismatch ispeed and ospeed\n");
1063 		error = EINVAL;
1064 		goto done;
1065 	}
1066 	t->c_ispeed = t->c_ospeed;
1067 
1068 	if (sc->sc_callback->ucom_pre_param) {
1069 		/* Let the lower layer verify the parameters */
1070 		error = (sc->sc_callback->ucom_pre_param) (sc, t);
1071 		if (error) {
1072 			DPRINTF("callback error = %d\n", error);
1073 			goto done;
1074 		}
1075 	}
1076 
1077 	/* Disable transfers */
1078 	sc->sc_flag &= ~UCOM_FLAG_GP_DATA;
1079 
1080 	/* Queue baud rate programming command first */
1081 	ucom_queue_command(sc, ucom_cfg_param, t,
1082 	    &sc->sc_param_task[0].hdr,
1083 	    &sc->sc_param_task[1].hdr);
1084 
1085 	/* Queue transfer enable command last */
1086 	ucom_queue_command(sc, ucom_cfg_start_transfers, NULL,
1087 	    &sc->sc_start_task[0].hdr,
1088 	    &sc->sc_start_task[1].hdr);
1089 
1090 	if (t->c_cflag & CRTS_IFLOW) {
1091 		sc->sc_flag |= UCOM_FLAG_RTS_IFLOW;
1092 	} else if (sc->sc_flag & UCOM_FLAG_RTS_IFLOW) {
1093 		sc->sc_flag &= ~UCOM_FLAG_RTS_IFLOW;
1094 		ucom_modem(tp, SER_RTS, 0);
1095 	}
1096 done:
1097 	if (error) {
1098 		if (opened) {
1099 			ucom_close(tp);
1100 		}
1101 	}
1102 	return (error);
1103 }
1104 
1105 static void
1106 ucom_outwakeup(struct tty *tp)
1107 {
1108 	struct ucom_softc *sc = tty_softc(tp);
1109 
1110 	mtx_assert(sc->sc_mtx, MA_OWNED);
1111 
1112 	DPRINTF("sc = %p\n", sc);
1113 
1114 	if (!(sc->sc_flag & UCOM_FLAG_HL_READY)) {
1115 		/* The higher layer is not ready */
1116 		return;
1117 	}
1118 	ucom_start_transfers(sc);
1119 }
1120 
1121 /*------------------------------------------------------------------------*
1122  *	ucom_get_data
1123  *
1124  * Return values:
1125  * 0: No data is available.
1126  * Else: Data is available.
1127  *------------------------------------------------------------------------*/
1128 uint8_t
1129 ucom_get_data(struct ucom_softc *sc, struct usb_page_cache *pc,
1130     uint32_t offset, uint32_t len, uint32_t *actlen)
1131 {
1132 	struct usb_page_search res;
1133 	struct tty *tp = sc->sc_tty;
1134 	uint32_t cnt;
1135 	uint32_t offset_orig;
1136 
1137 	mtx_assert(sc->sc_mtx, MA_OWNED);
1138 
1139 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
1140 		unsigned int temp;
1141 
1142 		/* get total TX length */
1143 
1144 		temp = ucom_cons_tx_high - ucom_cons_tx_low;
1145 		temp %= UCOM_CONS_BUFSIZE;
1146 
1147 		/* limit TX length */
1148 
1149 		if (temp > (UCOM_CONS_BUFSIZE - ucom_cons_tx_low))
1150 			temp = (UCOM_CONS_BUFSIZE - ucom_cons_tx_low);
1151 
1152 		if (temp > len)
1153 			temp = len;
1154 
1155 		/* copy in data */
1156 
1157 		usbd_copy_in(pc, offset, ucom_cons_tx_buf + ucom_cons_tx_low, temp);
1158 
1159 		/* update counters */
1160 
1161 		ucom_cons_tx_low += temp;
1162 		ucom_cons_tx_low %= UCOM_CONS_BUFSIZE;
1163 
1164 		/* store actual length */
1165 
1166 		*actlen = temp;
1167 
1168 		return (temp ? 1 : 0);
1169 	}
1170 
1171 	if (tty_gone(tp) ||
1172 	    !(sc->sc_flag & UCOM_FLAG_GP_DATA)) {
1173 		actlen[0] = 0;
1174 		return (0);		/* multiport device polling */
1175 	}
1176 	offset_orig = offset;
1177 
1178 	while (len != 0) {
1179 
1180 		usbd_get_page(pc, offset, &res);
1181 
1182 		if (res.length > len) {
1183 			res.length = len;
1184 		}
1185 		/* copy data directly into USB buffer */
1186 		cnt = ttydisc_getc(tp, res.buffer, res.length);
1187 
1188 		offset += cnt;
1189 		len -= cnt;
1190 
1191 		if (cnt < res.length) {
1192 			/* end of buffer */
1193 			break;
1194 		}
1195 	}
1196 
1197 	actlen[0] = offset - offset_orig;
1198 
1199 	DPRINTF("cnt=%d\n", actlen[0]);
1200 
1201 	if (actlen[0] == 0) {
1202 		return (0);
1203 	}
1204 	return (1);
1205 }
1206 
1207 void
1208 ucom_put_data(struct ucom_softc *sc, struct usb_page_cache *pc,
1209     uint32_t offset, uint32_t len)
1210 {
1211 	struct usb_page_search res;
1212 	struct tty *tp = sc->sc_tty;
1213 	char *buf;
1214 	uint32_t cnt;
1215 
1216 	mtx_assert(sc->sc_mtx, MA_OWNED);
1217 
1218 	if (sc->sc_flag & UCOM_FLAG_CONSOLE) {
1219 		unsigned int temp;
1220 
1221 		/* get maximum RX length */
1222 
1223 		temp = (UCOM_CONS_BUFSIZE - 1) - ucom_cons_rx_high + ucom_cons_rx_low;
1224 		temp %= UCOM_CONS_BUFSIZE;
1225 
1226 		/* limit RX length */
1227 
1228 		if (temp > (UCOM_CONS_BUFSIZE - ucom_cons_rx_high))
1229 			temp = (UCOM_CONS_BUFSIZE - ucom_cons_rx_high);
1230 
1231 		if (temp > len)
1232 			temp = len;
1233 
1234 		/* copy out data */
1235 
1236 		usbd_copy_out(pc, offset, ucom_cons_rx_buf + ucom_cons_rx_high, temp);
1237 
1238 		/* update counters */
1239 
1240 		ucom_cons_rx_high += temp;
1241 		ucom_cons_rx_high %= UCOM_CONS_BUFSIZE;
1242 
1243 		return;
1244 	}
1245 
1246 	if (tty_gone(tp))
1247 		return;			/* multiport device polling */
1248 
1249 	if (len == 0)
1250 		return;			/* no data */
1251 
1252 	/* set a flag to prevent recursation ? */
1253 
1254 	while (len > 0) {
1255 
1256 		usbd_get_page(pc, offset, &res);
1257 
1258 		if (res.length > len) {
1259 			res.length = len;
1260 		}
1261 		len -= res.length;
1262 		offset += res.length;
1263 
1264 		/* pass characters to tty layer */
1265 
1266 		buf = res.buffer;
1267 		cnt = res.length;
1268 
1269 		/* first check if we can pass the buffer directly */
1270 
1271 		if (ttydisc_can_bypass(tp)) {
1272 			if (ttydisc_rint_bypass(tp, buf, cnt) != cnt) {
1273 				DPRINTF("tp=%p, data lost\n", tp);
1274 			}
1275 			continue;
1276 		}
1277 		/* need to loop */
1278 
1279 		for (cnt = 0; cnt != res.length; cnt++) {
1280 			if (ttydisc_rint(tp, buf[cnt], 0) == -1) {
1281 				/* XXX what should we do? */
1282 
1283 				DPRINTF("tp=%p, lost %d "
1284 				    "chars\n", tp, res.length - cnt);
1285 				break;
1286 			}
1287 		}
1288 	}
1289 	ttydisc_rint_done(tp);
1290 }
1291 
1292 static void
1293 ucom_free(void *xsc)
1294 {
1295 	struct ucom_softc *sc = xsc;
1296 
1297 	mtx_lock(sc->sc_mtx);
1298 	sc->sc_ttyfreed = 1;
1299 	cv_signal(&sc->sc_cv);
1300 	mtx_unlock(sc->sc_mtx);
1301 }
1302 
1303 static cn_probe_t ucom_cnprobe;
1304 static cn_init_t ucom_cninit;
1305 static cn_term_t ucom_cnterm;
1306 static cn_getc_t ucom_cngetc;
1307 static cn_putc_t ucom_cnputc;
1308 
1309 CONSOLE_DRIVER(ucom);
1310 
1311 static void
1312 ucom_cnprobe(struct consdev  *cp)
1313 {
1314 	if (ucom_cons_unit != -1)
1315 		cp->cn_pri = CN_NORMAL;
1316 	else
1317 		cp->cn_pri = CN_DEAD;
1318 
1319 	strlcpy(cp->cn_name, "ucom", sizeof(cp->cn_name));
1320 }
1321 
1322 static void
1323 ucom_cninit(struct consdev  *cp)
1324 {
1325 }
1326 
1327 static void
1328 ucom_cnterm(struct consdev  *cp)
1329 {
1330 }
1331 
1332 static int
1333 ucom_cngetc(struct consdev *cd)
1334 {
1335 	struct ucom_softc *sc = ucom_cons_softc;
1336 	int c;
1337 
1338 	if (sc == NULL)
1339 		return (-1);
1340 
1341 	mtx_lock(sc->sc_mtx);
1342 
1343 	if (ucom_cons_rx_low != ucom_cons_rx_high) {
1344 		c = ucom_cons_rx_buf[ucom_cons_rx_low];
1345 		ucom_cons_rx_low ++;
1346 		ucom_cons_rx_low %= UCOM_CONS_BUFSIZE;
1347 	} else {
1348 		c = -1;
1349 	}
1350 
1351 	/* start USB transfers */
1352 	ucom_outwakeup(sc->sc_tty);
1353 
1354 	mtx_unlock(sc->sc_mtx);
1355 
1356 	/* poll if necessary */
1357 	if (kdb_active && sc->sc_callback->ucom_poll)
1358 		(sc->sc_callback->ucom_poll) (sc);
1359 
1360 	return (c);
1361 }
1362 
1363 static void
1364 ucom_cnputc(struct consdev *cd, int c)
1365 {
1366 	struct ucom_softc *sc = ucom_cons_softc;
1367 	unsigned int temp;
1368 
1369 	if (sc == NULL)
1370 		return;
1371 
1372  repeat:
1373 
1374 	mtx_lock(sc->sc_mtx);
1375 
1376 	/* compute maximum TX length */
1377 
1378 	temp = (UCOM_CONS_BUFSIZE - 1) - ucom_cons_tx_high + ucom_cons_tx_low;
1379 	temp %= UCOM_CONS_BUFSIZE;
1380 
1381 	if (temp) {
1382 		ucom_cons_tx_buf[ucom_cons_tx_high] = c;
1383 		ucom_cons_tx_high ++;
1384 		ucom_cons_tx_high %= UCOM_CONS_BUFSIZE;
1385 	}
1386 
1387 	/* start USB transfers */
1388 	ucom_outwakeup(sc->sc_tty);
1389 
1390 	mtx_unlock(sc->sc_mtx);
1391 
1392 	/* poll if necessary */
1393 	if (kdb_active && sc->sc_callback->ucom_poll) {
1394 		(sc->sc_callback->ucom_poll) (sc);
1395 		/* simple flow control */
1396 		if (temp == 0)
1397 			goto repeat;
1398 	}
1399 }
1400 
1401 #if defined(GDB)
1402 
1403 #include <gdb/gdb.h>
1404 
1405 static gdb_probe_f ucom_gdbprobe;
1406 static gdb_init_f ucom_gdbinit;
1407 static gdb_term_f ucom_gdbterm;
1408 static gdb_getc_f ucom_gdbgetc;
1409 static gdb_putc_f ucom_gdbputc;
1410 
1411 GDB_DBGPORT(sio, ucom_gdbprobe, ucom_gdbinit, ucom_gdbterm, ucom_gdbgetc, ucom_gdbputc);
1412 
1413 static int
1414 ucom_gdbprobe(void)
1415 {
1416 	return ((ucom_cons_softc != NULL) ? 0 : -1);
1417 }
1418 
1419 static void
1420 ucom_gdbinit(void)
1421 {
1422 }
1423 
1424 static void
1425 ucom_gdbterm(void)
1426 {
1427 }
1428 
1429 static void
1430 ucom_gdbputc(int c)
1431 {
1432         ucom_cnputc(NULL, c);
1433 }
1434 
1435 static int
1436 ucom_gdbgetc(void)
1437 {
1438         return (ucom_cngetc(NULL));
1439 }
1440 
1441 #endif
1442