xref: /freebsd/sys/dev/sound/dummy.c (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2024 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 <mixer_if.h>
44 
45 #define DUMMY_NPCHAN	1
46 #define DUMMY_NRCHAN	1
47 #define DUMMY_NCHAN	(DUMMY_NPCHAN + DUMMY_NRCHAN)
48 
49 struct dummy_chan {
50 	struct dummy_softc *sc;
51 	struct pcm_channel *chan;
52 	struct snd_dbuf *buf;
53 	struct pcmchan_caps *caps;
54 	uint32_t ptr;
55 	int dir;
56 	int run;
57 };
58 
59 struct dummy_softc {
60 	struct snddev_info info;
61 	device_t dev;
62 	uint32_t cap_fmts[4];
63 	struct pcmchan_caps caps;
64 	int chnum;
65 	struct dummy_chan chans[DUMMY_NCHAN];
66 	struct callout callout;
67 	struct mtx *lock;
68 };
69 
70 static bool
71 dummy_active(struct dummy_softc *sc)
72 {
73 	struct dummy_chan *ch;
74 	int i;
75 
76 	snd_mtxassert(sc->lock);
77 
78 	for (i = 0; i < sc->chnum; i++) {
79 		ch = &sc->chans[i];
80 		if (ch->run)
81 			return (true);
82 	}
83 
84 	/* No channel is running at the moment. */
85 	return (false);
86 }
87 
88 static void
89 dummy_chan_io(void *arg)
90 {
91 	struct dummy_softc *sc = arg;
92 	struct dummy_chan *ch;
93 	int i = 0;
94 
95 	/* Do not reschedule if no channel is running. */
96 	if (!dummy_active(sc))
97 		return;
98 
99 	for (i = 0; i < sc->chnum; i++) {
100 		ch = &sc->chans[i];
101 		if (!ch->run)
102 			continue;
103 		if (ch->dir == PCMDIR_PLAY)
104 			ch->ptr += sndbuf_getblksz(ch->buf);
105 		else
106 			sndbuf_fillsilence(ch->buf);
107 		snd_mtxunlock(sc->lock);
108 		chn_intr(ch->chan);
109 		snd_mtxlock(sc->lock);
110 	}
111 	callout_schedule(&sc->callout, 1);
112 }
113 
114 static int
115 dummy_chan_free(kobj_t obj, void *data)
116 {
117 	struct dummy_chan *ch =data;
118 	uint8_t *buf;
119 
120 	buf = sndbuf_getbuf(ch->buf);
121 	if (buf != NULL)
122 		free(buf, M_DEVBUF);
123 
124 	return (0);
125 }
126 
127 static void *
128 dummy_chan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b,
129     struct pcm_channel *c, int dir)
130 {
131 	struct dummy_softc *sc;
132 	struct dummy_chan *ch;
133 	uint8_t *buf;
134 	size_t bufsz;
135 
136 	sc = devinfo;
137 
138 	snd_mtxlock(sc->lock);
139 
140 	ch = &sc->chans[sc->chnum++];
141 	ch->sc = sc;
142 	ch->dir = dir;
143 	ch->chan = c;
144 	ch->buf = b;
145 	ch->caps = &sc->caps;
146 
147 	snd_mtxunlock(sc->lock);
148 
149 	bufsz = pcm_getbuffersize(sc->dev, 2048, 2048, 65536);
150 	buf = malloc(bufsz, M_DEVBUF, M_WAITOK | M_ZERO);
151 	if (sndbuf_setup(ch->buf, buf, bufsz) != 0) {
152 		dummy_chan_free(obj, ch);
153 		return (NULL);
154 	}
155 
156 	return (ch);
157 }
158 
159 static int
160 dummy_chan_setformat(kobj_t obj, void *data, uint32_t format)
161 {
162 	struct dummy_chan *ch = data;
163 	int i;
164 
165 	for (i = 0; ch->caps->fmtlist[i]; i++)
166 		if (format == ch->caps->fmtlist[i])
167 			return (0);
168 
169 	return (EINVAL);
170 }
171 
172 static uint32_t
173 dummy_chan_setspeed(kobj_t obj, void *data, uint32_t speed)
174 {
175 	struct dummy_chan *ch = data;
176 
177 	RANGE(speed, ch->caps->minspeed, ch->caps->maxspeed);
178 
179 	return (speed);
180 }
181 
182 static uint32_t
183 dummy_chan_setblocksize(kobj_t obj, void *data, uint32_t blocksize)
184 {
185 	struct dummy_chan *ch = data;
186 
187 	return (sndbuf_getblksz(ch->buf));
188 }
189 
190 static int
191 dummy_chan_trigger(kobj_t obj, void *data, int go)
192 {
193 	struct dummy_chan *ch = data;
194 	struct dummy_softc *sc = ch->sc;
195 
196 	snd_mtxlock(sc->lock);
197 
198 	switch (go) {
199 	case PCMTRIG_START:
200 		ch->ptr = 0;
201 		ch->run = 1;
202 		callout_reset(&sc->callout, 1, dummy_chan_io, sc);
203 		break;
204 	case PCMTRIG_STOP:
205 	case PCMTRIG_ABORT:
206 		ch->run = 0;
207 		/* If all channels are stopped, stop the callout as well. */
208 		if (!dummy_active(sc))
209 			callout_stop(&sc->callout);
210 	default:
211 		break;
212 	}
213 
214 	snd_mtxunlock(sc->lock);
215 
216 	return (0);
217 }
218 
219 static uint32_t
220 dummy_chan_getptr(kobj_t obj, void *data)
221 {
222 	struct dummy_chan *ch = data;
223 
224 	return (ch->run ? ch->ptr : 0);
225 }
226 
227 static struct pcmchan_caps *
228 dummy_chan_getcaps(kobj_t obj, void *data)
229 {
230 	struct dummy_chan *ch = data;
231 
232 	return (ch->caps);
233 }
234 
235 static kobj_method_t dummy_chan_methods[] = {
236 	KOBJMETHOD(channel_init,	dummy_chan_init),
237 	KOBJMETHOD(channel_free,	dummy_chan_free),
238 	KOBJMETHOD(channel_setformat,	dummy_chan_setformat),
239 	KOBJMETHOD(channel_setspeed,	dummy_chan_setspeed),
240 	KOBJMETHOD(channel_setblocksize,dummy_chan_setblocksize),
241 	KOBJMETHOD(channel_trigger,	dummy_chan_trigger),
242 	KOBJMETHOD(channel_getptr,	dummy_chan_getptr),
243 	KOBJMETHOD(channel_getcaps,	dummy_chan_getcaps),
244 	KOBJMETHOD_END
245 };
246 
247 CHANNEL_DECLARE(dummy_chan);
248 
249 static int
250 dummy_mixer_init(struct snd_mixer *m)
251 {
252 	struct dummy_softc *sc;
253 
254 	sc = mix_getdevinfo(m);
255 	if (sc == NULL)
256 		return (-1);
257 
258 	pcm_setflags(sc->dev, pcm_getflags(sc->dev) | SD_F_SOFTPCMVOL);
259 	mix_setdevs(m, SOUND_MASK_PCM | SOUND_MASK_VOLUME | SOUND_MASK_RECLEV);
260 	mix_setrecdevs(m, SOUND_MASK_RECLEV);
261 
262 	return (0);
263 }
264 
265 static int
266 dummy_mixer_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
267 {
268 	return (0);
269 }
270 
271 static uint32_t
272 dummy_mixer_setrecsrc(struct snd_mixer *m, uint32_t src)
273 {
274 	return (src == SOUND_MASK_RECLEV ? src : 0);
275 }
276 
277 static kobj_method_t dummy_mixer_methods[] = {
278 	KOBJMETHOD(mixer_init,		dummy_mixer_init),
279 	KOBJMETHOD(mixer_set,		dummy_mixer_set),
280 	KOBJMETHOD(mixer_setrecsrc,	dummy_mixer_setrecsrc),
281 	KOBJMETHOD_END
282 };
283 
284 MIXER_DECLARE(dummy_mixer);
285 
286 static void
287 dummy_identify(driver_t *driver, device_t parent)
288 {
289 	if (device_find_child(parent, driver->name, -1) != NULL)
290 		return;
291 	if (BUS_ADD_CHILD(parent, 0, driver->name, -1) == NULL)
292 		device_printf(parent, "add child failed\n");
293 }
294 
295 static int
296 dummy_probe(device_t dev)
297 {
298 	device_set_desc(dev, "Dummy Audio Device");
299 
300 	return (0);
301 }
302 
303 static int
304 dummy_attach(device_t dev)
305 {
306 	struct dummy_softc *sc;
307 	char status[SND_STATUSLEN];
308 	int i = 0;
309 
310 	sc = device_get_softc(dev);
311 	sc->dev = dev;
312 	sc->lock = snd_mtxcreate(device_get_nameunit(dev), "snd_dummy softc");
313 	callout_init_mtx(&sc->callout, sc->lock, 0);
314 
315 	sc->cap_fmts[0] = SND_FORMAT(AFMT_S32_LE, 2, 0);
316 	sc->cap_fmts[1] = SND_FORMAT(AFMT_S24_LE, 2, 0);
317 	sc->cap_fmts[2] = SND_FORMAT(AFMT_S16_LE, 2, 0);
318 	sc->cap_fmts[3] = 0;
319 	sc->caps = (struct pcmchan_caps){
320 		8000,		/* minspeed */
321 		96000,		/* maxspeed */
322 		sc->cap_fmts,	/* fmtlist */
323 		0,		/* caps */
324 	};
325 
326 	pcm_setflags(dev, pcm_getflags(dev) | SD_F_MPSAFE);
327 	pcm_init(dev, sc);
328 	for (i = 0; i < DUMMY_NPCHAN; i++)
329 		pcm_addchan(dev, PCMDIR_PLAY, &dummy_chan_class, sc);
330 	for (i = 0; i < DUMMY_NRCHAN; i++)
331 		pcm_addchan(dev, PCMDIR_REC, &dummy_chan_class, sc);
332 
333 	snprintf(status, SND_STATUSLEN, "on %s",
334 	    device_get_nameunit(device_get_parent(dev)));
335 	if (pcm_register(dev, status))
336 		return (ENXIO);
337 	mixer_init(dev, &dummy_mixer_class, sc);
338 
339 	return (0);
340 }
341 
342 static int
343 dummy_detach(device_t dev)
344 {
345 	struct dummy_softc *sc = device_get_softc(dev);
346 	int err;
347 
348 	err = pcm_unregister(dev);
349 	callout_drain(&sc->callout);
350 	snd_mtxfree(sc->lock);
351 
352 	return (err);
353 }
354 
355 static device_method_t dummy_methods[] = {
356 	/* Device interface */
357 	DEVMETHOD(device_identify,	dummy_identify),
358 	DEVMETHOD(device_probe,		dummy_probe),
359 	DEVMETHOD(device_attach,	dummy_attach),
360 	DEVMETHOD(device_detach,	dummy_detach),
361 	DEVMETHOD_END
362 };
363 
364 static driver_t dummy_driver = {
365 	"pcm",
366 	dummy_methods,
367 	sizeof(struct dummy_softc),
368 };
369 
370 DRIVER_MODULE(snd_dummy, nexus, dummy_driver, 0, 0);
371 MODULE_DEPEND(snd_dummy, sound, SOUND_MINVER, SOUND_PREFVER, SOUND_MAXVER);
372 MODULE_VERSION(snd_dummy, 1);
373