xref: /netbsd-src/sys/dev/pad/pad.c (revision ae082add65442546470c0ba499a860ee89eed305)
1 /* $NetBSD: pad.c,v 1.78 2022/03/31 19:30:16 pgoyette Exp $ */
2 
3 /*-
4  * Copyright (c) 2007 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: pad.c,v 1.78 2022/03/31 19:30:16 pgoyette Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/types.h>
34 
35 #include <sys/audioio.h>
36 #include <sys/buf.h>
37 #include <sys/condvar.h>
38 #include <sys/conf.h>
39 #include <sys/device.h>
40 #include <sys/file.h>
41 #include <sys/filedesc.h>
42 #include <sys/kauth.h>
43 #include <sys/kernel.h>
44 #include <sys/kmem.h>
45 #include <sys/module.h>
46 #include <sys/poll.h>
47 #include <sys/proc.h>
48 #include <sys/select.h>
49 #include <sys/stat.h>
50 #include <sys/vnode.h>
51 
52 #include <dev/audio/audio_if.h>
53 #include <dev/audio/audiovar.h>
54 
55 #include <dev/pad/padvar.h>
56 
57 #include "ioconf.h"
58 
59 /* #define PAD_DEBUG */
60 #ifdef PAD_DEBUG
61 #define DPRINTF(fmt...)	printf(fmt)
62 #else
63 #define DPRINTF(fmt...) /**/
64 #endif
65 
66 #define PADFREQ		44100
67 #define PADCHAN		2
68 #define PADPREC		16
69 
70 typedef struct pad_block {
71 	uint8_t		*pb_ptr;
72 	int		pb_len;
73 } pad_block_t;
74 
75 enum {
76 	PAD_OUTPUT_CLASS,
77 	PAD_INPUT_CLASS,
78 	PAD_OUTPUT_MASTER_VOLUME,
79 	PAD_INPUT_DAC_VOLUME,
80 	PAD_ENUM_LAST,
81 };
82 
83 static int	pad_match(device_t, cfdata_t, void *);
84 static void	pad_attach(device_t, device_t, void *);
85 static int	pad_detach(device_t, int);
86 static void	pad_childdet(device_t, device_t);
87 
88 static int	pad_query_format(void *, audio_format_query_t *);
89 static int	pad_set_format(void *, int,
90 		    const audio_params_t *, const audio_params_t *,
91 		    audio_filter_reg_t *, audio_filter_reg_t *);
92 static int	pad_start_output(void *, void *, int,
93 		    void (*)(void *), void *);
94 static int	pad_halt_output(void *);
95 static int	pad_getdev(void *, struct audio_device *);
96 static int	pad_set_port(void *, mixer_ctrl_t *);
97 static int	pad_get_port(void *, mixer_ctrl_t *);
98 static int	pad_query_devinfo(void *, mixer_devinfo_t *);
99 static int	pad_get_props(void *);
100 static void	pad_get_locks(void *, kmutex_t **, kmutex_t **);
101 
102 static void	pad_done_output(void *);
103 static void	pad_swvol_codec(audio_filter_arg_t *);
104 
105 static void	pad_close(struct pad_softc *);
106 static int	pad_read(struct pad_softc *, off_t *, struct uio *,
107 		    kauth_cred_t, int);
108 
109 static int	fops_pad_close(struct file *);
110 static int	fops_pad_read(struct file *, off_t *, struct uio *,
111 		    kauth_cred_t, int);
112 static int	fops_pad_write(struct file *, off_t *, struct uio *,
113 		    kauth_cred_t, int);
114 static int	fops_pad_ioctl(struct file *, u_long, void *);
115 static int	fops_pad_kqfilter(struct file *, struct knote *);
116 static int	fops_pad_poll(struct file *, int);
117 static int	fops_pad_stat(struct file *, struct stat *);
118 static int	fops_pad_mmap(struct file *, off_t *, size_t, int, int *, int *,
119 		    struct uvm_object **, int *);
120 
121 static const struct audio_hw_if pad_hw_if = {
122 	.query_format	= pad_query_format,
123 	.set_format	= pad_set_format,
124 	.start_output	= pad_start_output,
125 	.halt_output	= pad_halt_output,
126 	.getdev		= pad_getdev,
127 	.set_port	= pad_set_port,
128 	.get_port	= pad_get_port,
129 	.query_devinfo	= pad_query_devinfo,
130 	.get_props	= pad_get_props,
131 	.get_locks	= pad_get_locks,
132 };
133 
134 #define PAD_NFORMATS	1
135 static const struct audio_format pad_formats[PAD_NFORMATS] = {
136 	{
137 		.mode		= AUMODE_PLAY,
138 		.encoding	= AUDIO_ENCODING_SLINEAR_LE,
139 		.validbits	= PADPREC,
140 		.precision	= PADPREC,
141 		.channels	= PADCHAN,
142 		.channel_mask	= AUFMT_STEREO,
143 		.frequency_type	= 1,
144 		.frequency	= { PADFREQ },
145 	},
146 };
147 
148 extern void	padattach(int);
149 
150 static int	pad_add_block(struct pad_softc *, uint8_t *, int);
151 static int	pad_get_block(struct pad_softc *, pad_block_t *, int);
152 
153 static dev_type_open(pad_open);
154 
155 const struct cdevsw pad_cdevsw = {
156 	.d_open		= pad_open,
157 	.d_close	= noclose,
158 	.d_read		= noread,
159 	.d_write	= nowrite,
160 	.d_ioctl	= noioctl,
161 	.d_stop		= nostop,
162 	.d_tty		= notty,
163 	.d_poll		= nopoll,
164 	.d_mmap		= nommap,
165 	.d_kqfilter	= nokqfilter,
166 	.d_discard	= nodiscard,
167 	.d_flag		= D_OTHER | D_MPSAFE,
168 };
169 
170 const struct fileops pad_fileops = {
171 	.fo_name	= "pad",
172 	.fo_read	= fops_pad_read,
173 	.fo_write	= fops_pad_write,
174 	.fo_ioctl	= fops_pad_ioctl,
175 	.fo_fcntl	= fnullop_fcntl,
176 	.fo_stat	= fops_pad_stat,
177 	.fo_poll	= fops_pad_poll,
178 	.fo_close	= fops_pad_close,
179 	.fo_mmap	= fops_pad_mmap,
180 	.fo_kqfilter	= fops_pad_kqfilter,
181 	.fo_restart	= fnullop_restart
182 };
183 
184 CFATTACH_DECL2_NEW(pad, sizeof(struct pad_softc),
185     pad_match, pad_attach, pad_detach,
186     NULL, NULL, pad_childdet);
187 
188 void
189 padattach(int n)
190 {
191 	int error;
192 
193 	error = config_cfattach_attach(pad_cd.cd_name, &pad_ca);
194 	if (error) {
195 		aprint_error("%s: couldn't register cfattach: %d\n",
196 		    pad_cd.cd_name, error);
197 		config_cfdriver_detach(&pad_cd);
198 		return;
199 	}
200 }
201 
202 static int
203 pad_match(device_t parent, cfdata_t data, void *opaque)
204 {
205 
206 	return 1;
207 }
208 
209 static void
210 pad_attach(device_t parent, device_t self, void *opaque)
211 {
212 	struct pad_softc *sc = device_private(self);
213 
214 	KASSERT(KERNEL_LOCKED_P());
215 
216 	aprint_normal_dev(self, "outputs: 44100Hz, 16-bit, stereo\n");
217 
218 	sc->sc_dev = self;
219 
220 	cv_init(&sc->sc_condvar, device_xname(sc->sc_dev));
221 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
222 	mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_SOFTCLOCK);
223 	callout_init(&sc->sc_pcallout, CALLOUT_MPSAFE);
224 	callout_setfunc(&sc->sc_pcallout, pad_done_output, sc);
225 
226 	sc->sc_swvol = 255;
227 	sc->sc_buflen = 0;
228 	sc->sc_rpos = sc->sc_wpos = 0;
229 	sc->sc_audiodev = audio_attach_mi(&pad_hw_if, sc, sc->sc_dev);
230 
231 	if (!pmf_device_register(sc->sc_dev, NULL, NULL))
232 		aprint_error_dev(sc->sc_dev,
233 		    "couldn't establish power handler\n");
234 
235 	sc->sc_open = 1;
236 }
237 
238 static int
239 pad_detach(device_t self, int flags)
240 {
241 	struct pad_softc *sc = device_private(self);
242 	int cmaj, mn;
243 	int error;
244 
245 	KASSERT(KERNEL_LOCKED_P());
246 
247 	/* Prevent detach without going through close -- e.g., drvctl.  */
248 	if (sc->sc_open)
249 		return EBUSY;
250 
251 	error = config_detach_children(self, flags);
252 	if (error)
253 		return error;
254 
255 	cmaj = cdevsw_lookup_major(&pad_cdevsw);
256 	mn = device_unit(sc->sc_dev);
257 	vdevgone(cmaj, mn, mn, VCHR);
258 
259 	pmf_device_deregister(sc->sc_dev);
260 
261 	callout_destroy(&sc->sc_pcallout);
262 	mutex_destroy(&sc->sc_lock);
263 	mutex_destroy(&sc->sc_intr_lock);
264 	cv_destroy(&sc->sc_condvar);
265 
266 	return 0;
267 }
268 
269 static void
270 pad_childdet(device_t self, device_t child)
271 {
272 	struct pad_softc *sc = device_private(self);
273 
274 	KASSERT(KERNEL_LOCKED_P());
275 
276 	if (child == sc->sc_audiodev)
277 		sc->sc_audiodev = NULL;
278 }
279 
280 static int
281 pad_add_block(struct pad_softc *sc, uint8_t *blk, int blksize)
282 {
283 	int l;
284 
285 	KASSERT(blksize >= 0);
286 	KASSERT(mutex_owned(&sc->sc_intr_lock));
287 
288 	if (blksize > PAD_BUFSIZE ||
289 	    sc->sc_buflen > PAD_BUFSIZE - (unsigned)blksize)
290 		return ENOBUFS;
291 
292 	if (sc->sc_wpos + blksize <= PAD_BUFSIZE)
293 		memcpy(sc->sc_audiobuf + sc->sc_wpos, blk, blksize);
294 	else {
295 		l = PAD_BUFSIZE - sc->sc_wpos;
296 		memcpy(sc->sc_audiobuf + sc->sc_wpos, blk, l);
297 		memcpy(sc->sc_audiobuf, blk + l, blksize - l);
298 	}
299 
300 	sc->sc_wpos += blksize;
301 	if (sc->sc_wpos >= PAD_BUFSIZE)
302 		sc->sc_wpos -= PAD_BUFSIZE;
303 
304 	sc->sc_buflen += blksize;
305 	cv_broadcast(&sc->sc_condvar);
306 
307 	return 0;
308 }
309 
310 static int
311 pad_get_block(struct pad_softc *sc, pad_block_t *pb, int maxblksize)
312 {
313 	int l, blksize, error;
314 
315 	KASSERT(maxblksize > 0);
316 	KASSERT(mutex_owned(&sc->sc_intr_lock));
317 
318 	while (sc->sc_buflen == 0) {
319 		DPRINTF("%s: wait\n", __func__);
320 		error = cv_wait_sig(&sc->sc_condvar, &sc->sc_intr_lock);
321 		DPRINTF("%s: wake up %d\n", __func__, err);
322 		if (error)
323 			return error;
324 	}
325 	blksize = uimin(maxblksize, sc->sc_buflen);
326 
327 	pb->pb_ptr = (sc->sc_audiobuf + sc->sc_rpos);
328 	if (sc->sc_rpos + blksize < PAD_BUFSIZE) {
329 		pb->pb_len = blksize;
330 		sc->sc_rpos += blksize;
331 	} else {
332 		l = PAD_BUFSIZE - sc->sc_rpos;
333 		pb->pb_len = l;
334 		sc->sc_rpos = 0;
335 	}
336 	sc->sc_buflen -= pb->pb_len;
337 
338 	return 0;
339 }
340 
341 static int
342 pad_open(dev_t dev, int flags, int fmt, struct lwp *l)
343 {
344 	struct file *fp = NULL;
345 	device_t self;
346 	struct pad_softc *sc = NULL;
347 	cfdata_t cf = NULL;
348 	int error, fd;
349 
350 	error = fd_allocfile(&fp, &fd);
351 	if (error)
352 		goto out;
353 
354 	cf = kmem_alloc(sizeof(*cf), KM_SLEEP);
355 	cf->cf_name = pad_cd.cd_name;
356 	cf->cf_atname = pad_cd.cd_name;
357 	cf->cf_unit = 0;
358 	cf->cf_fstate = FSTATE_STAR;
359 
360 	self = config_attach_pseudo(cf);
361 	if (self == NULL) {
362 		error = ENXIO;
363 		goto out;
364 	}
365 	sc = device_private(self);
366 	KASSERT(sc->sc_dev == self);
367 	cf = NULL;
368 
369 	error = fd_clone(fp, fd, flags, &pad_fileops, sc);
370 	KASSERT(error == EMOVEFD);
371 	fp = NULL;
372 	sc = NULL;
373 
374 out:	if (sc)
375 		pad_close(sc);
376 	if (cf)
377 		kmem_free(cf, sizeof(*cf));
378 	if (fp)
379 		fd_abort(curproc, fp, fd);
380 	return error;
381 }
382 
383 static void
384 pad_close(struct pad_softc *sc)
385 {
386 	device_t self = sc->sc_dev;
387 	cfdata_t cf = device_cfdata(self);
388 
389 	/*
390 	 * XXX This is not quite enough to prevent racing with drvctl
391 	 * detach.  What can happen:
392 	 *
393 	 *	cpu0				cpu1
394 	 *
395 	 *	pad_close
396 	 *	take kernel lock
397 	 *	sc->sc_open = 0
398 	 *	drop kernel lock
399 	 *	wait for config_misc_lock
400 	 *					drvctl detach
401 	 *					take kernel lock
402 	 *					drop kernel lock
403 	 *					wait for config_misc_lock
404 	 *					retake kernel lock
405 	 *					drop config_misc_lock
406 	 *	take config_misc_lock
407 	 *	wait for kernel lock
408 	 *					pad_detach (sc_open=0 already)
409 	 *					free device
410 	 *					drop kernel lock
411 	 *	use device after free
412 	 *
413 	 * We need a way to grab a reference to the device so it won't
414 	 * be freed until we're done -- it's OK if we config_detach
415 	 * twice as long as it's idempotent, but not OK if the first
416 	 * config_detach frees the struct device before the second one
417 	 * has finished handling it.
418 	 */
419 	KERNEL_LOCK(1, NULL);
420 	KASSERT(sc->sc_open);
421 	sc->sc_open = 0;
422 	(void)config_detach(self, DETACH_FORCE);
423 	KERNEL_UNLOCK_ONE(NULL);
424 
425 	kmem_free(cf, sizeof(*cf));
426 }
427 
428 static int
429 fops_pad_close(struct file *fp)
430 {
431 	struct pad_softc *sc = fp->f_pad;
432 
433 	pad_close(sc);
434 
435 	return 0;
436 }
437 
438 static int
439 fops_pad_poll(struct file *fp, int events)
440 {
441 
442 	return POLLERR;
443 }
444 
445 static int
446 fops_pad_kqfilter(struct file *fp, struct knote *kn)
447 {
448 	struct pad_softc *sc = fp->f_pad;
449 	dev_t dev;
450 
451 	dev = makedev(cdevsw_lookup_major(&pad_cdevsw),
452 	    device_unit(sc->sc_dev));
453 
454 	return seltrue_kqfilter(dev, kn);
455 }
456 
457 static int
458 fops_pad_ioctl(struct file *fp, u_long cmd, void *data)
459 {
460 
461 	return ENODEV;
462 }
463 
464 static int
465 fops_pad_stat(struct file *fp, struct stat *st)
466 {
467 	struct pad_softc *sc = fp->f_pad;
468 
469 	memset(st, 0, sizeof(*st));
470 
471 	st->st_dev = makedev(cdevsw_lookup_major(&pad_cdevsw),
472 	    device_unit(sc->sc_dev));
473 
474 	st->st_uid = kauth_cred_geteuid(fp->f_cred);
475 	st->st_gid = kauth_cred_getegid(fp->f_cred);
476 	st->st_mode = S_IFCHR;
477 
478 	return 0;
479 }
480 
481 static int
482 fops_pad_mmap(struct file *fp, off_t *offp, size_t len, int prot, int *flagsp,
483     int *advicep, struct uvm_object **uobjp, int *maxprotp)
484 {
485 
486 	return 1;
487 }
488 
489 static int
490 fops_pad_read(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred,
491     int ioflag)
492 {
493 	struct pad_softc *sc = fp->f_pad;
494 
495 	return pad_read(sc, offp, uio, cred, ioflag);
496 }
497 
498 static int
499 pad_read(struct pad_softc *sc, off_t *offp, struct uio *uio, kauth_cred_t cred,
500     int ioflag)
501 {
502 	pad_block_t pb;
503 	int err;
504 
505 	err = 0;
506 	DPRINTF("%s: resid=%zu\n", __func__, uio->uio_resid);
507 	while (uio->uio_resid > 0) {
508 		mutex_enter(&sc->sc_intr_lock);
509 		err = pad_get_block(sc, &pb, MIN(uio->uio_resid, INT_MAX));
510 		mutex_exit(&sc->sc_intr_lock);
511 		if (err)
512 			break;
513 
514 		DPRINTF("%s: move %d\n", __func__, pb.pb_len);
515 		err = uiomove(pb.pb_ptr, pb.pb_len, uio);
516 		if (err)
517 			break;
518 	}
519 
520 	return err;
521 }
522 
523 static int
524 fops_pad_write(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred,
525     int ioflag)
526 {
527 
528 	return EOPNOTSUPP;
529 }
530 
531 static int
532 pad_query_format(void *opaque, audio_format_query_t *afp)
533 {
534 
535 	return audio_query_format(pad_formats, PAD_NFORMATS, afp);
536 }
537 
538 static int
539 pad_set_format(void *opaque, int setmode,
540     const audio_params_t *play, const audio_params_t *rec,
541     audio_filter_reg_t *pfil, audio_filter_reg_t *rfil)
542 {
543 	struct pad_softc *sc = opaque;
544 
545 	KASSERT(mutex_owned(&sc->sc_lock));
546 
547 	/* XXX playback only */
548 	pfil->codec = pad_swvol_codec;
549 	pfil->context = sc;
550 
551 	return 0;
552 }
553 
554 static int
555 pad_start_output(void *opaque, void *block, int blksize,
556     void (*intr)(void *), void *intrarg)
557 {
558 	struct pad_softc *sc = opaque;
559 	int err;
560 	int ms;
561 
562 	KASSERT(mutex_owned(&sc->sc_intr_lock));
563 
564 	sc->sc_intr = intr;
565 	sc->sc_intrarg = intrarg;
566 
567 	DPRINTF("%s: blksize=%d\n", __func__, blksize);
568 	err = pad_add_block(sc, block, blksize);
569 
570 	ms = blksize * 1000 / PADCHAN / (PADPREC / NBBY) / PADFREQ;
571 	DPRINTF("%s: callout ms=%d\n", __func__, ms);
572 	callout_schedule(&sc->sc_pcallout, mstohz(ms));
573 
574 	return err;
575 }
576 
577 static int
578 pad_halt_output(void *opaque)
579 {
580 	struct pad_softc *sc = opaque;
581 
582 	DPRINTF("%s\n", __func__);
583 	KASSERT(mutex_owned(&sc->sc_intr_lock));
584 
585 	callout_halt(&sc->sc_pcallout, &sc->sc_intr_lock);
586 
587 	sc->sc_intr = NULL;
588 	sc->sc_intrarg = NULL;
589 	sc->sc_buflen = 0;
590 	sc->sc_rpos = sc->sc_wpos = 0;
591 
592 	return 0;
593 }
594 
595 static void
596 pad_done_output(void *arg)
597 {
598 	struct pad_softc *sc = arg;
599 
600 	DPRINTF("%s\n", __func__);
601 
602 	mutex_enter(&sc->sc_intr_lock);
603 	(*sc->sc_intr)(sc->sc_intrarg);
604 	mutex_exit(&sc->sc_intr_lock);
605 }
606 
607 static int
608 pad_getdev(void *opaque, struct audio_device *ret)
609 {
610 
611 	strlcpy(ret->name, "Virtual Audio", sizeof(ret->name));
612 	strlcpy(ret->version, osrelease, sizeof(ret->version));
613 	strlcpy(ret->config, "pad", sizeof(ret->config));
614 
615 	return 0;
616 }
617 
618 static int
619 pad_set_port(void *opaque, mixer_ctrl_t *mc)
620 {
621 	struct pad_softc *sc = opaque;
622 
623 	KASSERT(mutex_owned(&sc->sc_lock));
624 
625 	switch (mc->dev) {
626 	case PAD_OUTPUT_MASTER_VOLUME:
627 	case PAD_INPUT_DAC_VOLUME:
628 		if (mc->un.value.num_channels != 1)
629 			return EINVAL;
630 		sc->sc_swvol = mc->un.value.level[AUDIO_MIXER_LEVEL_MONO];
631 		return 0;
632 	}
633 
634 	return ENXIO;
635 }
636 
637 static int
638 pad_get_port(void *opaque, mixer_ctrl_t *mc)
639 {
640 	struct pad_softc *sc = opaque;
641 
642 	KASSERT(mutex_owned(&sc->sc_lock));
643 
644 	switch (mc->dev) {
645 	case PAD_OUTPUT_MASTER_VOLUME:
646 	case PAD_INPUT_DAC_VOLUME:
647 		if (mc->un.value.num_channels != 1)
648 			return EINVAL;
649 		mc->un.value.level[AUDIO_MIXER_LEVEL_MONO] = sc->sc_swvol;
650 		return 0;
651 	}
652 
653 	return ENXIO;
654 }
655 
656 static int
657 pad_query_devinfo(void *opaque, mixer_devinfo_t *di)
658 {
659 	struct pad_softc *sc __diagused = opaque;
660 
661 	KASSERT(mutex_owned(&sc->sc_lock));
662 
663 	switch (di->index) {
664 	case PAD_OUTPUT_CLASS:
665 		di->mixer_class = PAD_OUTPUT_CLASS;
666 		strcpy(di->label.name, AudioCoutputs);
667 		di->type = AUDIO_MIXER_CLASS;
668 		di->next = di->prev = AUDIO_MIXER_LAST;
669 		return 0;
670 	case PAD_INPUT_CLASS:
671 		di->mixer_class = PAD_INPUT_CLASS;
672 		strcpy(di->label.name, AudioCinputs);
673 		di->type = AUDIO_MIXER_CLASS;
674 		di->next = di->prev = AUDIO_MIXER_LAST;
675 		return 0;
676 	case PAD_OUTPUT_MASTER_VOLUME:
677 		di->mixer_class = PAD_OUTPUT_CLASS;
678 		strcpy(di->label.name, AudioNmaster);
679 		di->type = AUDIO_MIXER_VALUE;
680 		di->next = di->prev = AUDIO_MIXER_LAST;
681 		di->un.v.num_channels = 1;
682 		strcpy(di->un.v.units.name, AudioNvolume);
683 		return 0;
684 	case PAD_INPUT_DAC_VOLUME:
685 		di->mixer_class = PAD_INPUT_CLASS;
686 		strcpy(di->label.name, AudioNdac);
687 		di->type = AUDIO_MIXER_VALUE;
688 		di->next = di->prev = AUDIO_MIXER_LAST;
689 		di->un.v.num_channels = 1;
690 		strcpy(di->un.v.units.name, AudioNvolume);
691 		return 0;
692 	}
693 
694 	return ENXIO;
695 }
696 
697 static int
698 pad_get_props(void *opaque)
699 {
700 
701 	return AUDIO_PROP_PLAYBACK;
702 }
703 
704 static void
705 pad_get_locks(void *opaque, kmutex_t **intr, kmutex_t **thread)
706 {
707 	struct pad_softc *sc = opaque;
708 
709 	*intr = &sc->sc_intr_lock;
710 	*thread = &sc->sc_lock;
711 }
712 
713 static void
714 pad_swvol_codec(audio_filter_arg_t *arg)
715 {
716 	struct pad_softc *sc = arg->context;
717 	const aint_t *src;
718 	aint_t *dst;
719 	u_int sample_count;
720 	u_int i;
721 
722 	src = arg->src;
723 	dst = arg->dst;
724 	sample_count = arg->count * arg->srcfmt->channels;
725 	for (i = 0; i < sample_count; i++) {
726 		aint2_t v = (aint2_t)(*src++);
727 		v = v * sc->sc_swvol / 255;
728 		*dst++ = (aint_t)v;
729 	}
730 }
731 
732 MODULE(MODULE_CLASS_DRIVER, pad, "audio");
733 
734 #ifdef _MODULE
735 
736 #include "ioconf.c"
737 
738 devmajor_t cmajor = NODEVMAJOR, bmajor = NODEVMAJOR;
739 
740 /*
741  * We need our own version of cfattach since config(1)'s ioconf does not
742  * generate what we need
743  */
744 
745 static struct cfattach *pad_cfattachinit[] = { &pad_ca, NULL };
746 
747 static struct cfattachinit pad_cfattach[] = {
748 	{ "pad", pad_cfattachinit },
749 	{ NULL, NULL }
750 };
751 #endif
752 
753 static int
754 pad_modcmd(modcmd_t cmd, void *arg)
755 {
756 	int error = 0;
757 
758 	switch (cmd) {
759 	case MODULE_CMD_INIT:
760 #ifdef _MODULE
761 		error = devsw_attach(pad_cd.cd_name, NULL, &bmajor,
762 			    &pad_cdevsw, &cmajor);
763 		if (error)
764 			break;
765 
766 		pad_cfattach[1] = cfattach_ioconf_pad[0];
767 		error = config_init_component(cfdriver_ioconf_pad,
768 		    pad_cfattach, cfdata_ioconf_pad);
769 		if (error) {
770 			devsw_detach(NULL, &pad_cdevsw);
771 			break;
772 		}
773 #endif
774 		break;
775 
776 	case MODULE_CMD_FINI:
777 #ifdef _MODULE
778 		error = config_fini_component(cfdriver_ioconf_pad,
779 		    pad_cfattach, cfdata_ioconf_pad);
780 		if (error == 0)
781 			devsw_detach(NULL, &pad_cdevsw);
782 #endif
783 		break;
784 
785 	default:
786 		error = ENOTTY;
787 	}
788 
789 	return error;
790 }
791