wsmux.c revision 1.1 1 /* $NetBSD: wsmux.c,v 1.1 1999/07/29 18:20:03 augustss Exp $ */
2
3 /*
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Author: Lennart Augustsson <augustss (at) carlstedt.se>
8 * Carlstedt Research & Technology
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 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the NetBSD
21 * Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39 #include "wsmux.h"
40 #include "wsdisplay.h"
41 #include "wskbd.h"
42
43 #if NWSMUX > 0 || (NWSDISPLAY > 0 && NWSKBD > 0)
44
45 /*
46 * wscons mux device.
47 *
48 * The mux device is a collection of real mice and keyboards and acts as
49 * a merge point for all the events from the different real devices.
50 */
51
52 #include <sys/param.h>
53 #include <sys/conf.h>
54 #include <sys/ioctl.h>
55 #include <sys/fcntl.h>
56 #include <sys/kernel.h>
57 #include <sys/malloc.h>
58 #include <sys/proc.h>
59 #include <sys/queue.h>
60 #include <sys/syslog.h>
61 #include <sys/systm.h>
62 #include <sys/tty.h>
63 #include <sys/signalvar.h>
64 #include <sys/device.h>
65
66 #include "opt_wsdisplay_compat.h"
67
68 #include <dev/wscons/wsconsio.h>
69 #include <dev/wscons/wseventvar.h>
70 #include <dev/wscons/wscons_callbacks.h>
71 #include <dev/wscons/wsmuxvar.h>
72
73 #ifdef WSMUX_DEBUG
74 #define DPRINTF(x) if (wsmuxdebug) printf x
75 int wsmuxdebug = 0;
76 #else
77 #define DPRINTF(x)
78 #endif
79
80 struct wsplink {
81 LIST_ENTRY(wsplink) next;
82 int type;
83 struct wsmux_softc *mux; /* our mux device */
84 /* The rest of the fields reflect a value in the multiplexee. */
85 struct device *sc; /* softc */
86 struct wseventvar *sc_mevents; /* event var */
87 struct wsmux_softc **sc_muxp; /* pointer to us */
88 struct wsmuxops *sc_ops;
89 };
90
91 cdev_decl(wsmux);
92
93 int wsmuxdoclose __P((struct device *, int, int, struct proc *));
94 int wsmux_set_display __P((struct device *, struct wsmux_softc *));
95
96 int nwsmux = NWSMUX;
97 struct wsmux_softc *wsmuxdevs[NWSMUX];
98
99 void wsmuxattach __P((int));
100
101 struct wsmuxops wsmux_muxops = {
102 wsmuxopen, wsmuxdoclose, wsmuxdoioctl, wsmux_displayioctl,
103 wsmux_set_display
104 };
105
106 /* From upper level */
107 void
108 wsmuxattach(n)
109 int n;
110 {
111 int i;
112
113 #if 0
114 /* Called too late. We use static allocation instead. */
115 nwsmux = n;
116 wsmuxdevs = malloc(n * sizeof (struct wsmux_softc *),
117 M_DEVBUF, M_NOWAIT);
118 if (wsmuxdevs == 0)
119 panic("wsmuxattach: out of memory\n");
120 #endif
121
122 /* Make sure all muxes are there. */
123 for (i = 0; i < nwsmux; i++)
124 if (!wsmuxdevs[i])
125 wsmuxdevs[i] = wsmux_create("wsmux", i);
126 }
127
128 struct wsmux_softc *
129 wsmux_create(name, unit)
130 const char *name;
131 int unit;
132 {
133 struct wsmux_softc *sc;
134
135 DPRINTF(("wsmux_create: allocating\n"));
136 sc = malloc(sizeof *sc, M_DEVBUF, M_NOWAIT);
137 if (!sc)
138 return (0);
139 memset(sc, 0, sizeof *sc);
140 LIST_INIT(&sc->sc_reals);
141 snprintf(sc->sc_dv.dv_xname, sizeof sc->sc_dv.dv_xname,
142 "%s%d", name, unit);
143 sc->sc_dv.dv_unit = unit;
144 return (sc);
145 }
146
147 /* From mouse or keyboard. */
148 void
149 wsmux_attach(n, type, dsc, ev, psp, ops)
150 int n;
151 int type;
152 struct device *dsc;
153 struct wseventvar *ev;
154 struct wsmux_softc **psp;
155 struct wsmuxops *ops;
156 {
157 struct wsmux_softc *sc;
158 int error;
159
160 DPRINTF(("wsmux_attach\n"));
161 if (n >= nwsmux || n < 0) {
162 printf("wsmux: attach device %d is out of range (%d..%d)\n",
163 n, 0, nwsmux-1);
164 return;
165 }
166 sc = wsmuxdevs[n];
167 if (sc == 0) {
168 sc = wsmux_create("wsmux", n);
169 if (sc == 0) {
170 printf("wsmux: attach out of memory\n");
171 return;
172 }
173 wsmuxdevs[n] = sc;
174 }
175 error = wsmux_attach_sc(sc, type, dsc, ev, psp, ops);
176 if (error)
177 printf("wsmux_attach: error=%d\n", error);
178 }
179
180 int
181 wsmux_attach_sc(sc, type, dsc, ev, psp, ops)
182 struct wsmux_softc *sc;
183 int type;
184 struct device *dsc;
185 struct wseventvar *ev;
186 struct wsmux_softc **psp;
187 struct wsmuxops *ops;
188 {
189 struct wsplink *m;
190 int error;
191
192 DPRINTF(("wsmux_attach_sc: %s: type=%d dsc=%p, *psp=%p\n",
193 sc->sc_dv.dv_xname, type, dsc, *psp));
194 m = malloc(sizeof *m, M_DEVBUF, M_NOWAIT);
195 if (m == 0)
196 return (ENOMEM);
197 m->type = type;
198 m->mux = sc;
199 m->sc = dsc;
200 m->sc_mevents = ev;
201 m->sc_muxp = psp;
202 m->sc_ops = ops;
203 LIST_INSERT_HEAD(&sc->sc_reals, m, next);
204
205 if (sc->sc_displaydv) {
206 /* This is a display mux, so attach the new device to it. */
207 DPRINTF(("wsmux_attach_sc: %s: set display %p\n",
208 sc->sc_dv.dv_xname, sc->sc_displaydv));
209 error = 0;
210 if (m->sc_ops->dsetdisplay) {
211 error = m->sc_ops->dsetdisplay(m->sc, sc);
212 /* Ignore that the console already has a display. */
213 if (error == EBUSY)
214 error = 0;
215 if (!error) {
216 *m->sc_muxp = sc;
217 #ifdef WSDISPLAY_COMPAT_RAWKBD
218 DPRINTF(("wsmux_attach_sc: on %s set rawkbd=%d\n",
219 m->sc->dv_xname, sc->sc_rawkbd));
220 (void)m->sc_ops->dioctl(m->sc,
221 WSKBDIO_SETMODE,
222 (caddr_t)&sc->sc_rawkbd,
223 0, 0);
224 #endif
225 }
226 }
227 } else if (sc->sc_events.io) {
228 /* Mux is open, so open the new subdevice */
229 DPRINTF(("wsmux_attach_sc: %s: calling open of %s\n",
230 sc->sc_dv.dv_xname, m->sc->dv_xname));
231 /* mux already open, join in */
232 error = m->sc_ops->dopen(makedev(0, m->sc->dv_unit),
233 sc->sc_flags, sc->sc_mode, sc->sc_p);
234 if (!error)
235 *m->sc_muxp = sc;
236 } else {
237 DPRINTF(("wsmux_attach_sc: %s not open\n",
238 sc->sc_dv.dv_xname));
239 error = 0;
240 }
241 DPRINTF(("wsmux_attach_sc: done sc=%p psp=%p *psp=%p\n",
242 sc, psp, *psp));
243
244 return (error);
245 }
246
247 /* From mouse or keyboard. */
248 void
249 wsmux_detach(n, dsc)
250 int n;
251 struct device *dsc;
252 {
253 #ifdef DIAGNOSTIC
254 int error;
255
256 if (n >= nwsmux || n < 0) {
257 printf("wsmux_detach: detach is out of range\n");
258 return;
259 }
260 if ((error = wsmux_detach_sc(wsmuxdevs[n], dsc)))
261 printf("wsmux_detach: error=%d\n", error);
262 #else
263 (void)wsmux_detach_sc(wsmuxdevs[n], dsc);
264 #endif
265 }
266
267 int
268 wsmux_detach_sc(sc, dsc)
269 struct wsmux_softc *sc;
270 struct device *dsc;
271 {
272 struct wsplink *m;
273 int error;
274
275 DPRINTF(("wsmux_detach_sc: %s: dsc=%p\n", sc->sc_dv.dv_xname, dsc));
276 #ifdef DIAGNOSTIC
277 if (sc == 0) {
278 printf("wsmux_detach_sc: not allocated\n");
279 return (ENXIO);
280 }
281 #endif
282
283 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
284 if (m->sc == dsc)
285 break;
286 }
287 #ifdef DIAGNOSTIC
288 if (!m) {
289 printf("wsmux_detach_sc: not found\n");
290 return (ENXIO);
291 }
292 #endif
293 if (sc->sc_displaydv) {
294 if (m->sc_ops->dsetdisplay)
295 error = m->sc_ops->dsetdisplay(m->sc, 0);
296 if (error)
297 return (error);
298 *m->sc_muxp = 0;
299 } else if (*m->sc_muxp) {
300 DPRINTF(("wsmux_detach_sc: close\n"));
301 /* mux device is open, so close multiplexee */
302 m->sc_ops->dclose(m->sc, FREAD, 0, 0);
303 *m->sc_muxp = 0;
304 }
305
306 LIST_REMOVE(m, next);
307
308 free(m, M_DEVBUF);
309 DPRINTF(("wsmux_detach_sc: done sc=%p\n", sc));
310 return (0);
311 }
312
313 int
314 wsmuxopen(dev, flags, mode, p)
315 dev_t dev;
316 int flags, mode;
317 struct proc *p;
318 {
319 struct wsmux_softc *sc;
320 struct wsplink *m;
321 int unit, error, nopen, lasterror;
322
323 unit = minor(dev);
324 if (unit >= nwsmux || /* make sure it was attached */
325 (sc = wsmuxdevs[unit]) == NULL)
326 return (ENXIO);
327
328 DPRINTF(("wsmuxopen: %s: sc=%p\n", sc->sc_dv.dv_xname, sc));
329 if (!(flags & FREAD)) {
330 /* Not opening for read, only ioctl is available. */
331 return (0);
332 }
333
334 if (sc->sc_events.io)
335 return (EBUSY);
336
337 sc->sc_events.io = p;
338 sc->sc_flags = flags;
339 sc->sc_mode = mode;
340 sc->sc_p = p;
341 wsevent_init(&sc->sc_events); /* may cause sleep */
342
343 nopen = 0;
344 lasterror = 0;
345 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
346 if (!m->sc_mevents->io && !*m->sc_muxp) {
347 DPRINTF(("wsmuxopen: %s: m=%p dev=%s\n",
348 sc->sc_dv.dv_xname, m, m->sc->dv_xname));
349 error = m->sc_ops->dopen(makedev(0, m->sc->dv_unit),
350 flags, mode, p);
351 if (error) {
352 /* Ignore opens that fail */
353 lasterror = error;
354 DPRINTF(("wsmuxopen: open failed %d\n",
355 error));
356 } else {
357 nopen++;
358 *m->sc_muxp = sc;
359 }
360 }
361 }
362
363 if (nopen == 0 && lasterror != 0) {
364 wsevent_fini(&sc->sc_events);
365 sc->sc_events.io = NULL;
366 return (lasterror);
367 }
368
369 return (0);
370 }
371
372 int
373 wsmuxclose(dev, flags, mode, p)
374 dev_t dev;
375 int flags, mode;
376 struct proc *p;
377 {
378 return wsmuxdoclose(&wsmuxdevs[minor(dev)]->sc_dv, flags, mode, p);
379 }
380
381 int wsmuxdoclose(dv, flags, mode, p)
382 struct device *dv;
383 int flags, mode;
384 struct proc *p;
385 {
386 struct wsmux_softc *sc = (struct wsmux_softc *)dv;
387 struct wsplink *m;
388
389 DPRINTF(("wsmuxclose: %s: sc=%p\n", sc->sc_dv.dv_xname, sc));
390 if (!(flags & FREAD)) {
391 /* Not closing read, so read still allowed. */
392 return 0;
393 }
394
395 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
396 if (*m->sc_muxp == sc) {
397 DPRINTF(("wsmuxclose %s: m=%p dev=%s\n",
398 sc->sc_dv.dv_xname, m, m->sc->dv_xname));
399 m->sc_ops->dclose(m->sc, flags, mode, p);
400 *m->sc_muxp = 0;
401 }
402 }
403
404 wsevent_fini(&sc->sc_events);
405 sc->sc_events.io = NULL;
406
407 return (0);
408 }
409
410 int
411 wsmuxread(dev, uio, flags)
412 dev_t dev;
413 struct uio *uio;
414 int flags;
415 {
416 struct wsmux_softc *sc = wsmuxdevs[minor(dev)];
417
418 if (!sc->sc_events.io)
419 return (EACCES);
420
421 return (wsevent_read(&sc->sc_events, uio, flags));
422 }
423
424 int
425 wsmuxioctl(dev, cmd, data, flag, p)
426 dev_t dev;
427 u_long cmd;
428 caddr_t data;
429 int flag;
430 struct proc *p;
431 {
432 return wsmuxdoioctl(&wsmuxdevs[minor(dev)]->sc_dv, cmd, data, flag, p);
433 }
434
435 int
436 wsmuxdoioctl(dv, cmd, data, flag, p)
437 struct device *dv;
438 u_long cmd;
439 caddr_t data;
440 int flag;
441 struct proc *p;
442 {
443 struct wsmux_softc *sc = (struct wsmux_softc *)dv;
444 struct wsplink *m;
445 int error, ok;
446 int s, put, get, n;
447 struct wseventvar *evar;
448 struct wscons_event *ev;
449 struct timeval xxxtime;
450 struct wsmux_device_list *l;
451
452 DPRINTF(("wsmuxdoioctl: %s: sc=%p, cmd=%08lx\n",
453 sc->sc_dv.dv_xname, sc, cmd));
454
455 switch (cmd) {
456 case WSMUX_INJECTEVENT:
457 /* Inject an event, e.g., from moused. */
458 if (!sc->sc_events.io)
459 return (EACCES);
460
461 evar = &sc->sc_events;
462 s = spltty();
463 get = evar->get;
464 put = evar->put;
465 if (++put % WSEVENT_QSIZE == get) {
466 put--;
467 splx(s);
468 return (ENOSPC);
469 }
470 if (put >= WSEVENT_QSIZE)
471 put = 0;
472 ev = &evar->q[put];
473 *ev = *(struct wscons_event *)data;
474 microtime(&xxxtime);
475 TIMEVAL_TO_TIMESPEC(&xxxtime, &ev->time);
476 evar->put = put;
477 WSEVENT_WAKEUP(evar);
478 splx(s);
479 return (0);
480 case WSMUX_ADD_DEVICE:
481 #define d ((struct wsmux_device *)data)
482 switch (d->type) {
483 #if NWSMOUSE > 0
484 case WSMUX_MOUSE:
485 return (wsmouse_add_mux(d->idx, sc));
486 #endif
487 #if NWSKBD > 0
488 case WSMUX_KBD:
489 return (wskbd_add_mux(d->idx, sc));
490 #endif
491 case WSMUX_MUX:
492 return (wsmux_add_mux(d->idx, sc));
493 default:
494 return (EINVAL);
495 }
496 case WSMUX_REMOVE_DEVICE:
497 switch (d->type) {
498 #if NWSMOUSE > 0
499 case WSMUX_MOUSE:
500 return (wsmouse_rem_mux(d->idx, sc));
501 #endif
502 #if NWSKBD > 0
503 case WSMUX_KBD:
504 return (wskbd_rem_mux(d->idx, sc));
505 #endif
506 case WSMUX_MUX:
507 return (wsmux_rem_mux(d->idx, sc));
508 default:
509 return (EINVAL);
510 }
511 #undef d
512 case WSMUX_LIST_DEVICES:
513 l = (struct wsmux_device_list *)data;
514 for (n = 0, m = LIST_FIRST(&sc->sc_reals);
515 n < WSMUX_MAXDEV && m != NULL;
516 m = LIST_NEXT(m, next)) {
517 l->devices[n].type = m->type;
518 l->devices[n].idx = m->sc->dv_unit;
519 n++;
520 }
521 l->ndevices = n;
522 return (0);
523 #ifdef WSDISPLAY_COMPAT_RAWKBD
524 case WSKBDIO_SETMODE:
525 sc->sc_rawkbd = *(int *)data;
526 DPRINTF(("wsmuxdoioctl: save rawkbd = %d\n", sc->sc_rawkbd));
527 break;
528 #endif
529 default:
530 break;
531 }
532
533 if (sc->sc_events.io == NULL && sc->sc_displaydv == NULL)
534 return (EACCES);
535
536 /* Return 0 if any of the ioctl() succeeds, otherwise the last error */
537 error = 0;
538 ok = 0;
539 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
540 DPRINTF(("wsmuxdoioctl: m=%p *m->sc_muxp=%p sc=%p\n",
541 m, *m->sc_muxp, sc));
542 if (*m->sc_muxp == sc) {
543 DPRINTF(("wsmuxdoioctl: %s: m=%p dev=%s\n",
544 sc->sc_dv.dv_xname, m, m->sc->dv_xname));
545 error = m->sc_ops->dioctl(m->sc, cmd, data, flag, p);
546 if (!error)
547 ok = 1;
548 }
549 }
550 if (ok)
551 error = 0;
552
553 return (error);
554 }
555
556 int
557 wsmux_displayioctl(dv, cmd, data, flag, p)
558 struct device *dv;
559 u_long cmd;
560 caddr_t data;
561 int flag;
562 struct proc *p;
563 {
564 struct wsmux_softc *sc = (struct wsmux_softc *)dv;
565 struct wsplink *m;
566 int error, ok;
567
568 DPRINTF(("wsmux_displayioctl: %s: sc=%p, cmd=%08lx\n",
569 sc->sc_dv.dv_xname, sc, cmd));
570
571 #ifdef WSDISPLAY_COMPAT_RAWKBD
572 if (cmd == WSKBDIO_SETMODE) {
573 sc->sc_rawkbd = *(int *)data;
574 DPRINTF(("wsmux_displayioctl: rawkbd = %d\n", sc->sc_rawkbd));
575 }
576 #endif
577
578 /* Return 0 if any of the ioctl() succeeds, otherwise the last error */
579 error = 0;
580 ok = 0;
581 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
582 DPRINTF(("wsmux_displayioctl: m=%p sc=%p sc_muxp=%p\n",
583 m, sc, *m->sc_muxp));
584 if (m->sc_ops->ddispioctl && *m->sc_muxp == sc) {
585 error = m->sc_ops->ddispioctl(m->sc, cmd, data,
586 flag, p);
587 DPRINTF(("wsmux_displayioctl: m=%p dev=%s ==> %d\n",
588 m, m->sc->dv_xname, error));
589 if (!error)
590 ok = 1;
591 }
592 }
593 if (ok)
594 error = 0;
595
596 return (error);
597 }
598
599 int
600 wsmuxpoll(dev, events, p)
601 dev_t dev;
602 int events;
603 struct proc *p;
604 {
605 struct wsmux_softc *sc = wsmuxdevs[minor(dev)];
606
607 if (!sc->sc_events.io)
608 return (EACCES);
609
610 return (wsevent_poll(&sc->sc_events, events, p));
611 }
612
613 int
614 wsmux_set_display(dv, muxsc)
615 struct device *dv;
616 struct wsmux_softc *muxsc;
617 {
618 struct wsmux_softc *sc = (struct wsmux_softc *)dv;
619 struct wsmux_softc *nsc = muxsc ? sc : 0;
620 struct device *displaydv = muxsc ? muxsc->sc_displaydv : 0;
621 struct device *odisplaydv;
622 struct wsplink *m;
623 int error, ok;
624
625 DPRINTF(("wsmux_set_display: %s: displaydv=%p\n",
626 sc->sc_dv.dv_xname, displaydv));
627
628 if (displaydv) {
629 if (sc->sc_displaydv)
630 return (EBUSY);
631 } else {
632 if (sc->sc_displaydv == NULL)
633 return (ENXIO);
634 }
635
636 odisplaydv = sc->sc_displaydv;
637 sc->sc_displaydv = displaydv;
638
639 if (displaydv)
640 printf("%s: connecting to %s\n",
641 sc->sc_dv.dv_xname, displaydv->dv_xname);
642 ok = 0;
643 error = 0;
644 for (m = LIST_FIRST(&sc->sc_reals); m; m = LIST_NEXT(m, next)) {
645 if (m->sc_ops->dsetdisplay &&
646 (nsc ? m->sc_mevents->io == 0 && *m->sc_muxp == 0 :
647 *m->sc_muxp == sc)) {
648 error = m->sc_ops->dsetdisplay(m->sc, nsc);
649 DPRINTF(("wsmux_set_display: m=%p dev=%s error=%d\n",
650 m, m->sc->dv_xname, error));
651 if (!error) {
652 ok = 1;
653 *m->sc_muxp = nsc;
654 #ifdef WSDISPLAY_COMPAT_RAWKBD
655 DPRINTF(("wsmux_set_display: on %s set rawkbd=%d\n",
656 m->sc->dv_xname, sc->sc_rawkbd));
657 (void)m->sc_ops->dioctl(m->sc,
658 WSKBDIO_SETMODE,
659 (caddr_t)&sc->sc_rawkbd,
660 0, 0);
661 #endif
662 }
663 }
664 }
665 if (ok)
666 error = 0;
667
668 if (displaydv == NULL)
669 printf("%s: disconnecting from %s\n",
670 sc->sc_dv.dv_xname, odisplaydv->dv_xname);
671
672 return (error);
673 }
674
675 int
676 wsmux_add_mux(unit, muxsc)
677 int unit;
678 struct wsmux_softc *muxsc;
679 {
680 struct wsmux_softc *sc, *m;
681
682 if (unit < 0 || unit >= nwsmux || (sc = wsmuxdevs[unit]) == NULL)
683 return (ENXIO);
684
685 DPRINTF(("wsmux_add_mux: %s to %s\n", sc->sc_dv.dv_xname,
686 muxsc->sc_dv.dv_xname));
687
688 if (sc->sc_mux || sc->sc_events.io)
689 return (EBUSY);
690
691 /* The mux we are adding must not be an ancestor of it. */
692 for (m = muxsc->sc_mux; m; m = m->sc_mux)
693 if (m == sc)
694 return (EINVAL);
695
696 return (wsmux_attach_sc(muxsc, WSMUX_MUX, &sc->sc_dv, &sc->sc_events,
697 &sc->sc_mux, &wsmux_muxops));
698 }
699
700 int
701 wsmux_rem_mux(unit, muxsc)
702 int unit;
703 struct wsmux_softc *muxsc;
704 {
705 struct wsmux_softc *sc;
706
707 if (unit < 0 || unit >= nwsmux || (sc = wsmuxdevs[unit]) == NULL)
708 return (ENXIO);
709
710 DPRINTF(("wsmux_rem_mux: %s from %s\n", sc->sc_dv.dv_xname,
711 muxsc->sc_dv.dv_xname));
712
713 return (wsmux_detach_sc(muxsc, &sc->sc_dv));
714 }
715
716 #endif /* NWSMUX > 0 || (NWSDISPLAY > 0 && NWSKBD > 0) */
717