xref: /freebsd/sys/dev/sound/dummy.c (revision 64038db825d64fb4827fc8ee264ea0fa1a046d82)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2024-2025 The FreeBSD Foundation
5  *
6  * This software was developed by Christos Margiolis <christos@FreeBSD.org>
7  * under sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/bus.h>
37 
38 #ifdef HAVE_KERNEL_OPTION_HEADERS
39 #include "opt_snd.h"
40 #endif
41 
42 #include <dev/sound/pcm/sound.h>
43 #include <dev/sound/midi/mpu401.h>
44 
45 #include <mixer_if.h>
46 #include <mpufoi_if.h>
47 
48 #define DUMMY_NPCHAN	1
49 #define DUMMY_NRCHAN	1
50 #define DUMMY_NCHAN	(DUMMY_NPCHAN + DUMMY_NRCHAN)
51 
52 struct dummy_chan {
53 	struct dummy_softc *sc;
54 	struct pcm_channel *chan;
55 	struct snd_dbuf *buf;
56 	struct pcmchan_caps *caps;
57 	uint32_t ptr;
58 	int dir;
59 	int run;
60 };
61 
62 struct dummy_softc {
63 	struct snddev_info info;
64 	device_t dev;
65 	uint32_t cap_fmts[4];
66 	struct pcmchan_caps caps;
67 	int chnum;
68 	struct dummy_chan chans[DUMMY_NCHAN];
69 	struct callout callout;
70 	struct mtx lock;
71 	bool stopped;
72 	struct mpu401 *mpu;
73 	mpu401_intr_t *mpu_intr;
74 };
75 
76 static bool
77 dummy_active(struct dummy_softc *sc)
78 {
79 	struct dummy_chan *ch;
80 	int i;
81 
82 	mtx_assert(&sc->lock, MA_OWNED);
83 
84 	for (i = 0; i < sc->chnum; i++) {
85 		ch = &sc->chans[i];
86 		if (ch->run)
87 			return (true);
88 	}
89 
90 	/* No channel is running at the moment. */
91 	return (false);
92 }
93 
94 static void
95 dummy_chan_io(void *arg)
96 {
97 	struct dummy_softc *sc = arg;
98 	struct dummy_chan *ch;
99 	int i = 0;
100 
101 	if (sc->mpu_intr)
102 		(sc->mpu_intr)(sc->mpu);
103 
104 	if (sc->stopped)
105 		return;
106 
107 	/* Do not reschedule if no channel is running. */
108 	if (!dummy_active(sc))
109 		return;
110 
111 	for (i = 0; i < sc->chnum; i++) {
112 		ch = &sc->chans[i];
113 		if (!ch->run)
114 			continue;
115 		if (ch->dir == PCMDIR_REC)
116 			sndbuf_fillsilence(ch->buf);
117 		ch->ptr += ch->buf->blksz;
118 		ch->ptr %= ch->buf->bufsize;
119 		mtx_unlock(&sc->lock);
120 		chn_intr(ch->chan);
121 		mtx_lock(&sc->lock);
122 	}
123 	if (!sc->stopped)
124 		callout_schedule(&sc->callout, 1);
125 }
126 
127 static int
128 dummy_chan_free(kobj_t obj, void *data)
129 {
130 	struct dummy_chan *ch =data;
131 	uint8_t *buf;
132 
133 	buf = ch->buf->buf;
134 	free(buf, M_DEVBUF);
135 
136 	return (0);
137 }
138 
139 static void *
140 dummy_chan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
141     struct pcm_channel *c, int dir)
142 {
143 	struct dummy_softc *sc;
144 	struct dummy_chan *ch;
145 	uint8_t *buf;
146 	size_t bufsz;
147 
148 	sc = devinfo;
149 
150 	mtx_lock(&sc->lock);
151 
152 	ch = &sc->chans[sc->chnum++];
153 	ch->sc = sc;
154 	ch->dir = dir;
155 	ch->chan = c;
156 	ch->buf = b;
157 	ch->caps = &sc->caps;
158 
159 	mtx_unlock(&sc->lock);
160 
161 	bufsz = pcm_getbuffersize(sc->dev, 2048, 2048, 65536);
162 	buf = malloc(bufsz, M_DEVBUF, M_WAITOK | M_ZERO);
163 	if (sndbuf_setup(ch->buf, buf, bufsz) != 0) {
164 		dummy_chan_free(obj, ch);
165 		return (NULL);
166 	}
167 
168 	return (ch);
169 }
170 
171 static int
172 dummy_chan_setformat(kobj_t obj, void *data, uint32_t format)
173 {
174 	struct dummy_chan *ch = data;
175 	int i;
176 
177 	for (i = 0; ch->caps->fmtlist[i]; i++)
178 		if (format == ch->caps->fmtlist[i])
179 			return (0);
180 
181 	return (EINVAL);
182 }
183 
184 static uint32_t
185 dummy_chan_setspeed(kobj_t obj, void *data, uint32_t speed)
186 {
187 	struct dummy_chan *ch = data;
188 
189 	RANGE(speed, ch->caps->minspeed, ch->caps->maxspeed);
190 
191 	return (speed);
192 }
193 
194 static uint32_t
195 dummy_chan_setblocksize(kobj_t obj, void *data, uint32_t blocksize)
196 {
197 	struct dummy_chan *ch = data;
198 
199 	return (ch->buf->blksz);
200 }
201 
202 static int
203 dummy_chan_trigger(kobj_t obj, void *data, int go)
204 {
205 	struct dummy_chan *ch = data;
206 	struct dummy_softc *sc = ch->sc;
207 
208 	mtx_lock(&sc->lock);
209 
210 	if (sc->stopped) {
211 		mtx_unlock(&sc->lock);
212 		return (0);
213 	}
214 
215 	switch (go) {
216 	case PCMTRIG_START:
217 		ch->ptr = 0;
218 		ch->run = 1;
219 		callout_reset(&sc->callout, 1, dummy_chan_io, sc);
220 		break;
221 	case PCMTRIG_STOP:
222 	case PCMTRIG_ABORT:
223 		ch->run = 0;
224 		/* If all channels are stopped, stop the callout as well. */
225 		if (!dummy_active(sc))
226 			callout_stop(&sc->callout);
227 	default:
228 		break;
229 	}
230 
231 	mtx_unlock(&sc->lock);
232 
233 	return (0);
234 }
235 
236 static uint32_t
237 dummy_chan_getptr(kobj_t obj, void *data)
238 {
239 	struct dummy_chan *ch = data;
240 
241 	return (ch->run ? ch->ptr : 0);
242 }
243 
244 static struct pcmchan_caps *
245 dummy_chan_getcaps(kobj_t obj, void *data)
246 {
247 	struct dummy_chan *ch = data;
248 
249 	return (ch->caps);
250 }
251 
252 static kobj_method_t dummy_chan_methods[] = {
253 	KOBJMETHOD(channel_init,	dummy_chan_init),
254 	KOBJMETHOD(channel_free,	dummy_chan_free),
255 	KOBJMETHOD(channel_setformat,	dummy_chan_setformat),
256 	KOBJMETHOD(channel_setspeed,	dummy_chan_setspeed),
257 	KOBJMETHOD(channel_setblocksize,dummy_chan_setblocksize),
258 	KOBJMETHOD(channel_trigger,	dummy_chan_trigger),
259 	KOBJMETHOD(channel_getptr,	dummy_chan_getptr),
260 	KOBJMETHOD(channel_getcaps,	dummy_chan_getcaps),
261 	KOBJMETHOD_END
262 };
263 
264 CHANNEL_DECLARE(dummy_chan);
265 
266 static int
267 dummy_mixer_init(struct snd_mixer *m)
268 {
269 	struct dummy_softc *sc;
270 
271 	sc = mix_getdevinfo(m);
272 	if (sc == NULL)
273 		return (-1);
274 
275 	pcm_setflags(sc->dev, pcm_getflags(sc->dev) | SD_F_SOFTPCMVOL);
276 	mix_setdevs(m, SOUND_MASK_PCM | SOUND_MASK_VOLUME | SOUND_MASK_RECLEV);
277 	mix_setrecdevs(m, SOUND_MASK_RECLEV);
278 
279 	return (0);
280 }
281 
282 static int
283 dummy_mixer_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
284 {
285 	return (0);
286 }
287 
288 static uint32_t
289 dummy_mixer_setrecsrc(struct snd_mixer *m, uint32_t src)
290 {
291 	return (src == SOUND_MASK_RECLEV ? src : 0);
292 }
293 
294 static kobj_method_t dummy_mixer_methods[] = {
295 	KOBJMETHOD(mixer_init,		dummy_mixer_init),
296 	KOBJMETHOD(mixer_set,		dummy_mixer_set),
297 	KOBJMETHOD(mixer_setrecsrc,	dummy_mixer_setrecsrc),
298 	KOBJMETHOD_END
299 };
300 
301 MIXER_DECLARE(dummy_mixer);
302 
303 static uint8_t
304 dummy_mpu_read(struct mpu401 *arg, void *sc, int reg)
305 {
306 	return (0);
307 }
308 
309 static void
310 dummy_mpu_write(struct mpu401 *arg, void *sc, int reg, unsigned char b)
311 {
312 }
313 
314 static int
315 dummy_mpu_uninit(struct mpu401 *arg, void *cookie)
316 {
317 	struct dummy_softc *sc = cookie;
318 
319 	mtx_lock(&sc->lock);
320 	sc->mpu_intr = NULL;
321 	sc->mpu = NULL;
322 	mtx_unlock(&sc->lock);
323 
324 	return (0);
325 }
326 
327 static kobj_method_t dummy_mpu_methods[] = {
328 	KOBJMETHOD(mpufoi_read,		dummy_mpu_read),
329 	KOBJMETHOD(mpufoi_write,	dummy_mpu_write),
330 	KOBJMETHOD(mpufoi_uninit,	dummy_mpu_uninit),
331 	KOBJMETHOD_END
332 };
333 
334 static DEFINE_CLASS(dummy_mpu, dummy_mpu_methods, 0);
335 
336 static void
337 dummy_identify(driver_t *driver, device_t parent)
338 {
339 	if (device_find_child(parent, driver->name, DEVICE_UNIT_ANY) != NULL)
340 		return;
341 	if (BUS_ADD_CHILD(parent, 0, driver->name, DEVICE_UNIT_ANY) == NULL)
342 		device_printf(parent, "add child failed\n");
343 }
344 
345 static int
346 dummy_probe(device_t dev)
347 {
348 	device_set_desc(dev, "Dummy Audio Device");
349 
350 	return (0);
351 }
352 
353 static int
354 dummy_attach(device_t dev)
355 {
356 	struct dummy_softc *sc;
357 	char status[SND_STATUSLEN];
358 	int i = 0;
359 
360 	sc = device_get_softc(dev);
361 	sc->dev = dev;
362 	mtx_init(&sc->lock, device_get_nameunit(dev), "snd_dummy softc",
363 	    MTX_DEF);
364 	callout_init_mtx(&sc->callout, &sc->lock, 0);
365 
366 	sc->cap_fmts[0] = SND_FORMAT(AFMT_S32_LE, 2, 0);
367 	sc->cap_fmts[1] = SND_FORMAT(AFMT_S24_LE, 2, 0);
368 	sc->cap_fmts[2] = SND_FORMAT(AFMT_S16_LE, 2, 0);
369 	sc->cap_fmts[3] = 0;
370 	sc->caps = (struct pcmchan_caps){
371 		8000,		/* minspeed */
372 		96000,		/* maxspeed */
373 		sc->cap_fmts,	/* fmtlist */
374 		0,		/* caps */
375 	};
376 
377 	pcm_setflags(dev, pcm_getflags(dev) | SD_F_MPSAFE);
378 	pcm_init(dev, sc);
379 	for (i = 0; i < DUMMY_NPCHAN; i++)
380 		pcm_addchan(dev, PCMDIR_PLAY, &dummy_chan_class, sc);
381 	for (i = 0; i < DUMMY_NRCHAN; i++)
382 		pcm_addchan(dev, PCMDIR_REC, &dummy_chan_class, sc);
383 
384 	snprintf(status, SND_STATUSLEN, "on %s",
385 	    device_get_nameunit(device_get_parent(dev)));
386 	if (pcm_register(dev, status))
387 		return (ENXIO);
388 	mixer_init(dev, &dummy_mixer_class, sc);
389 
390 	/*
391 	 * Create an alias so that tests do not need to guess which one is the
392 	 * dummy device if there are more devices present in the system.
393 	 */
394 	make_dev_alias(sc->info.dsp_dev, "dsp.dummy");
395 
396 	sc->mpu = mpu401_init(&dummy_mpu_class, sc, dummy_chan_io,
397 	    &sc->mpu_intr);
398 	if (sc->mpu == NULL)
399 		return (ENXIO);
400 
401 	return (0);
402 }
403 
404 static int
405 dummy_detach(device_t dev)
406 {
407 	struct dummy_softc *sc = device_get_softc(dev);
408 	int err;
409 
410 	mtx_lock(&sc->lock);
411 	sc->stopped = true;
412 	mtx_unlock(&sc->lock);
413 	callout_drain(&sc->callout);
414 	err = pcm_unregister(dev);
415 	mpu401_uninit(sc->mpu);
416 	mtx_destroy(&sc->lock);
417 
418 	return (err);
419 }
420 
421 static device_method_t dummy_methods[] = {
422 	/* Device interface */
423 	DEVMETHOD(device_identify,	dummy_identify),
424 	DEVMETHOD(device_probe,		dummy_probe),
425 	DEVMETHOD(device_attach,	dummy_attach),
426 	DEVMETHOD(device_detach,	dummy_detach),
427 	DEVMETHOD_END
428 };
429 
430 static driver_t dummy_driver = {
431 	"pcm",
432 	dummy_methods,
433 	sizeof(struct dummy_softc),
434 };
435 
436 DRIVER_MODULE(snd_dummy, nexus, dummy_driver, 0, 0);
437 MODULE_DEPEND(snd_dummy, sound, SOUND_MINVER, SOUND_PREFVER, SOUND_MAXVER);
438 MODULE_VERSION(snd_dummy, 1);
439