xref: /freebsd/sys/arm/broadcom/bcm2835/bcm2835_audio.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
1 /*-
2  * Copyright (c) 2015 Oleksandr Tymoshenko <gonzo@freebsd.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #ifdef HAVE_KERNEL_OPTION_HEADERS
27 #include "opt_snd.h"
28 #endif
29 
30 #include <dev/sound/pcm/sound.h>
31 #include <dev/sound/chip.h>
32 
33 #include "mixer_if.h"
34 
35 #include "interface/compat/vchi_bsd.h"
36 #include "interface/vchi/vchi.h"
37 #include "interface/vchiq_arm/vchiq.h"
38 
39 #include "vc_vchi_audioserv_defs.h"
40 
41 SND_DECLARE_FILE("$FreeBSD$");
42 
43 /* Audio destination */
44 #define	DEST_AUTO		0
45 #define	DEST_HEADPHONES		1
46 #define	DEST_HDMI		2
47 
48 /* Playback state */
49 #define	PLAYBACK_IDLE		0
50 #define	PLAYBACK_PLAYING	1
51 #define	PLAYBACK_STOPPING	2
52 
53 /* Worker thread state */
54 #define	WORKER_RUNNING		0
55 #define	WORKER_STOPPING		1
56 #define	WORKER_STOPPED		2
57 
58 /*
59  * Worker thread flags, set to 1 in flags_pending
60  * when driver requests one or another operation
61  * from worker. Cleared to 0 once worker performs
62  * the operations.
63  */
64 #define	AUDIO_PARAMS		(1 << 0)
65 #define	AUDIO_PLAY		(1 << 1)
66 #define	AUDIO_STOP		(1 << 2)
67 
68 #define	VCHIQ_AUDIO_PACKET_SIZE	4000
69 #define	VCHIQ_AUDIO_BUFFER_SIZE	10*VCHIQ_AUDIO_PACKET_SIZE
70 
71 #define	VCHIQ_AUDIO_MAX_VOLUME
72 /* volume in terms of 0.01dB */
73 #define VCHIQ_AUDIO_VOLUME_MIN -10239
74 #define VCHIQ_AUDIO_VOLUME(db100) (uint32_t)(-((db100) << 8)/100)
75 
76 /* dB levels with 5% volume step */
77 static int db_levels[] = {
78 	VCHIQ_AUDIO_VOLUME_MIN, -4605, -3794, -3218, -2772,
79 	-2407, -2099, -1832, -1597, -1386,
80 	-1195, -1021, -861, -713, -575,
81 	-446, -325, -210, -102, 0,
82 };
83 
84 static uint32_t bcm2835_audio_playfmt[] = {
85 	SND_FORMAT(AFMT_U8, 1, 0),
86 	SND_FORMAT(AFMT_U8, 2, 0),
87 	SND_FORMAT(AFMT_S8, 1, 0),
88 	SND_FORMAT(AFMT_S8, 2, 0),
89 	SND_FORMAT(AFMT_S16_LE, 1, 0),
90 	SND_FORMAT(AFMT_S16_LE, 2, 0),
91 	SND_FORMAT(AFMT_U16_LE, 1, 0),
92 	SND_FORMAT(AFMT_U16_LE, 2, 0),
93 	0
94 };
95 
96 static struct pcmchan_caps bcm2835_audio_playcaps = {8000, 48000, bcm2835_audio_playfmt, 0};
97 
98 struct bcm2835_audio_info;
99 
100 struct bcm2835_audio_chinfo {
101 	struct bcm2835_audio_info *parent;
102 	struct pcm_channel *channel;
103 	struct snd_dbuf *buffer;
104 	uint32_t fmt, spd, blksz;
105 
106 	/* Pointer to first unsubmitted sample */
107 	uint32_t unsubmittedptr;
108 	/*
109 	 * Number of bytes in "submitted but not played"
110 	 * pseudo-buffer
111 	 */
112 	int available_space;
113 	int playback_state;
114 	uint64_t callbacks;
115 	uint64_t submitted_samples;
116 	uint64_t retrieved_samples;
117 	uint64_t underruns;
118 	int starved;
119 };
120 
121 struct bcm2835_audio_info {
122 	device_t dev;
123 	unsigned int bufsz;
124     	struct bcm2835_audio_chinfo pch;
125 	uint32_t dest, volume;
126 	struct intr_config_hook intr_hook;
127 
128 	/* VCHI data */
129 	VCHI_INSTANCE_T vchi_instance;
130 	VCHI_CONNECTION_T *vchi_connection;
131 	VCHI_SERVICE_HANDLE_T vchi_handle;
132 
133 	struct mtx lock;
134 	struct cv worker_cv;
135 
136 	uint32_t flags_pending;
137 
138 	/* Worker thread state */
139 	int worker_state;
140 };
141 
142 #define BCM2835_AUDIO_LOCK(sc)		mtx_lock(&(sc)->lock)
143 #define BCM2835_AUDIO_LOCKED(sc)	mtx_assert(&(sc)->lock, MA_OWNED)
144 #define BCM2835_AUDIO_UNLOCK(sc)	mtx_unlock(&(sc)->lock)
145 
146 static const char *
147 dest_description(uint32_t dest)
148 {
149 	switch (dest) {
150 		case DEST_AUTO:
151 			return "AUTO";
152 			break;
153 
154 		case DEST_HEADPHONES:
155 			return "HEADPHONES";
156 			break;
157 
158 		case DEST_HDMI:
159 			return "HDMI";
160 			break;
161 		default:
162 			return "UNKNOWN";
163 			break;
164 	}
165 }
166 
167 static void
168 bcm2835_worker_update_params(struct bcm2835_audio_info *sc)
169 {
170 
171 	BCM2835_AUDIO_LOCKED(sc);
172 
173 	sc->flags_pending |= AUDIO_PARAMS;
174 	cv_signal(&sc->worker_cv);
175 }
176 
177 static void
178 bcm2835_worker_play_start(struct bcm2835_audio_info *sc)
179 {
180 	BCM2835_AUDIO_LOCK(sc);
181 	sc->flags_pending &= ~(AUDIO_STOP);
182 	sc->flags_pending |= AUDIO_PLAY;
183 	cv_signal(&sc->worker_cv);
184 	BCM2835_AUDIO_UNLOCK(sc);
185 }
186 
187 static void
188 bcm2835_worker_play_stop(struct bcm2835_audio_info *sc)
189 {
190 	BCM2835_AUDIO_LOCK(sc);
191 	sc->flags_pending &= ~(AUDIO_PLAY);
192 	sc->flags_pending |= AUDIO_STOP;
193 	cv_signal(&sc->worker_cv);
194 	BCM2835_AUDIO_UNLOCK(sc);
195 }
196 
197 static void
198 bcm2835_audio_callback(void *param, const VCHI_CALLBACK_REASON_T reason, void *msg_handle)
199 {
200 	struct bcm2835_audio_info *sc = (struct bcm2835_audio_info *)param;
201 	int32_t status;
202 	uint32_t msg_len;
203 	VC_AUDIO_MSG_T m;
204 
205 	if (reason != VCHI_CALLBACK_MSG_AVAILABLE)
206 		return;
207 
208 	status = vchi_msg_dequeue(sc->vchi_handle,
209 	    &m, sizeof m, &msg_len, VCHI_FLAGS_NONE);
210 	if (status != 0)
211 		return;
212 	if (m.type == VC_AUDIO_MSG_TYPE_RESULT) {
213 		if (m.u.result.success) {
214 			device_printf(sc->dev,
215 			    "msg type %08x failed\n",
216 			    m.type);
217 		}
218 	} else if (m.type == VC_AUDIO_MSG_TYPE_COMPLETE) {
219 		struct bcm2835_audio_chinfo *ch = m.u.complete.cookie;
220 
221 		int count = m.u.complete.count & 0xffff;
222 		int perr = (m.u.complete.count & (1U << 30)) != 0;
223 		ch->callbacks++;
224 		if (perr)
225 			ch->underruns++;
226 
227 		BCM2835_AUDIO_LOCK(sc);
228 		if (ch->playback_state != PLAYBACK_IDLE) {
229 			/* Prevent LOR */
230 			BCM2835_AUDIO_UNLOCK(sc);
231 			chn_intr(sc->pch.channel);
232 			BCM2835_AUDIO_LOCK(sc);
233 		}
234 		/* We should check again, state might have changed */
235 		if (ch->playback_state != PLAYBACK_IDLE) {
236 			if (!perr) {
237 				if ((ch->available_space + count)> VCHIQ_AUDIO_BUFFER_SIZE) {
238 					device_printf(sc->dev, "inconsistent data in callback:\n");
239 					device_printf(sc->dev, "available_space == %d, count = %d, perr=%d\n",
240 					    ch->available_space, count, perr);
241 					device_printf(sc->dev,
242 					    "retrieved_samples = %lld, submitted_samples = %lld\n",
243 					    ch->retrieved_samples, ch->submitted_samples);
244 				}
245 				ch->available_space += count;
246 				ch->retrieved_samples += count;
247 			}
248 			if (perr || (ch->available_space >= VCHIQ_AUDIO_PACKET_SIZE))
249 				cv_signal(&sc->worker_cv);
250 		}
251 		BCM2835_AUDIO_UNLOCK(sc);
252 	} else
253 		printf("%s: unknown m.type: %d\n", __func__, m.type);
254 }
255 
256 /* VCHIQ stuff */
257 static void
258 bcm2835_audio_init(struct bcm2835_audio_info *sc)
259 {
260 	int status;
261 
262 	/* Initialize and create a VCHI connection */
263 	status = vchi_initialise(&sc->vchi_instance);
264 	if (status != 0) {
265 		printf("vchi_initialise failed: %d\n", status);
266 		return;
267 	}
268 
269 	status = vchi_connect(NULL, 0, sc->vchi_instance);
270 	if (status != 0) {
271 		printf("vchi_connect failed: %d\n", status);
272 		return;
273 	}
274 
275 	SERVICE_CREATION_T params = {
276 	    VCHI_VERSION_EX(VC_AUDIOSERV_VER, VC_AUDIOSERV_MIN_VER),
277 	    VC_AUDIO_SERVER_NAME,   /* 4cc service code */
278 	    sc->vchi_connection,    /* passed in fn pointers */
279 	    0,  /* rx fifo size */
280 	    0,  /* tx fifo size */
281 	    bcm2835_audio_callback,    /* service callback */
282 	    sc,   /* service callback parameter */
283 	    1,
284 	    1,
285 	    0   /* want crc check on bulk transfers */
286 	};
287 
288 	status = vchi_service_open(sc->vchi_instance, &params,
289 	    &sc->vchi_handle);
290 
291 	if (status != 0)
292 		sc->vchi_handle = VCHIQ_SERVICE_HANDLE_INVALID;
293 }
294 
295 static void
296 bcm2835_audio_release(struct bcm2835_audio_info *sc)
297 {
298 	int success;
299 
300 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
301 		success = vchi_service_close(sc->vchi_handle);
302 		if (success != 0)
303 			printf("vchi_service_close failed: %d\n", success);
304 		vchi_service_release(sc->vchi_handle);
305 		sc->vchi_handle = VCHIQ_SERVICE_HANDLE_INVALID;
306 	}
307 
308 	vchi_disconnect(sc->vchi_instance);
309 }
310 
311 static void
312 bcm2835_audio_reset_channel(struct bcm2835_audio_chinfo *ch)
313 {
314 
315 	ch->available_space = VCHIQ_AUDIO_BUFFER_SIZE;
316 	ch->unsubmittedptr = 0;
317 	sndbuf_reset(ch->buffer);
318 }
319 
320 static void
321 bcm2835_audio_start(struct bcm2835_audio_chinfo *ch)
322 {
323 	VC_AUDIO_MSG_T m;
324 	int ret;
325 	struct bcm2835_audio_info *sc = ch->parent;
326 
327 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
328 		m.type = VC_AUDIO_MSG_TYPE_START;
329 		ret = vchi_msg_queue(sc->vchi_handle,
330 		    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
331 
332 		if (ret != 0)
333 			printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
334 	}
335 }
336 
337 static void
338 bcm2835_audio_stop(struct bcm2835_audio_chinfo *ch)
339 {
340 	VC_AUDIO_MSG_T m;
341 	int ret;
342 	struct bcm2835_audio_info *sc = ch->parent;
343 
344 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
345 		m.type = VC_AUDIO_MSG_TYPE_STOP;
346 		m.u.stop.draining = 0;
347 
348 		ret = vchi_msg_queue(sc->vchi_handle,
349 		    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
350 
351 		if (ret != 0)
352 			printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
353 	}
354 }
355 
356 static void
357 bcm2835_audio_open(struct bcm2835_audio_info *sc)
358 {
359 	VC_AUDIO_MSG_T m;
360 	int ret;
361 
362 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
363 		m.type = VC_AUDIO_MSG_TYPE_OPEN;
364 		ret = vchi_msg_queue(sc->vchi_handle,
365 		    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
366 
367 		if (ret != 0)
368 			printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
369 	}
370 }
371 
372 static void
373 bcm2835_audio_update_controls(struct bcm2835_audio_info *sc, uint32_t volume, uint32_t dest)
374 {
375 	VC_AUDIO_MSG_T m;
376 	int ret, db;
377 
378 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
379 		m.type = VC_AUDIO_MSG_TYPE_CONTROL;
380 		m.u.control.dest = dest;
381 		if (volume > 99)
382 			volume = 99;
383 		db = db_levels[volume/5];
384 		m.u.control.volume = VCHIQ_AUDIO_VOLUME(db);
385 
386 		ret = vchi_msg_queue(sc->vchi_handle,
387 		    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
388 
389 		if (ret != 0)
390 			printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
391 	}
392 }
393 
394 static void
395 bcm2835_audio_update_params(struct bcm2835_audio_info *sc, uint32_t fmt, uint32_t speed)
396 {
397 	VC_AUDIO_MSG_T m;
398 	int ret;
399 
400 	if (sc->vchi_handle != VCHIQ_SERVICE_HANDLE_INVALID) {
401 		m.type = VC_AUDIO_MSG_TYPE_CONFIG;
402 		m.u.config.channels = AFMT_CHANNEL(fmt);
403 		m.u.config.samplerate = speed;
404 		m.u.config.bps = AFMT_BIT(fmt);
405 
406 		ret = vchi_msg_queue(sc->vchi_handle,
407 		    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
408 
409 		if (ret != 0)
410 			printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
411 	}
412 }
413 
414 static bool
415 bcm2835_audio_buffer_should_sleep(struct bcm2835_audio_chinfo *ch)
416 {
417 
418 	if (ch->playback_state != PLAYBACK_PLAYING)
419 		return (true);
420 
421 	/* Not enough data */
422 	if (sndbuf_getready(ch->buffer) < VCHIQ_AUDIO_PACKET_SIZE) {
423 		printf("starve\n");
424 		ch->starved++;
425 		return (true);
426 	}
427 
428 	/* Not enough free space */
429 	if (ch->available_space < VCHIQ_AUDIO_PACKET_SIZE) {
430 		return (true);
431 	}
432 
433 	return (false);
434 }
435 
436 static void
437 bcm2835_audio_write_samples(struct bcm2835_audio_chinfo *ch, void *buf, uint32_t count)
438 {
439 	struct bcm2835_audio_info *sc = ch->parent;
440 	VC_AUDIO_MSG_T m;
441 	int ret;
442 
443 	if (sc->vchi_handle == VCHIQ_SERVICE_HANDLE_INVALID) {
444 		return;
445 	}
446 
447 	m.type = VC_AUDIO_MSG_TYPE_WRITE;
448 	m.u.write.count = count;
449 	m.u.write.max_packet = VCHIQ_AUDIO_PACKET_SIZE;
450 	m.u.write.callback = NULL;
451 	m.u.write.cookie = ch;
452 	m.u.write.silence = 0;
453 
454 	ret = vchi_msg_queue(sc->vchi_handle,
455 	    &m, sizeof m, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
456 
457 	if (ret != 0)
458 		printf("%s: vchi_msg_queue failed (err %d)\n", __func__, ret);
459 
460 	while (count > 0) {
461 		int bytes = MIN((int)m.u.write.max_packet, (int)count);
462 		ret = vchi_msg_queue(sc->vchi_handle,
463 		    buf, bytes, VCHI_FLAGS_BLOCK_UNTIL_QUEUED, NULL);
464 		if (ret != 0)
465 			printf("%s: vchi_msg_queue failed: %d\n",
466 			    __func__, ret);
467 		buf = (char *)buf + bytes;
468 		count -= bytes;
469 	}
470 }
471 
472 static void
473 bcm2835_audio_worker(void *data)
474 {
475 	struct bcm2835_audio_info *sc = (struct bcm2835_audio_info *)data;
476 	struct bcm2835_audio_chinfo *ch = &sc->pch;
477 	uint32_t speed, format;
478 	uint32_t volume, dest;
479 	uint32_t flags;
480 	uint32_t count, size, readyptr;
481 	uint8_t *buf;
482 
483 	ch->playback_state = PLAYBACK_IDLE;
484 
485 	while (1) {
486 		if (sc->worker_state != WORKER_RUNNING)
487 			break;
488 
489 		BCM2835_AUDIO_LOCK(sc);
490 		/*
491 		 * wait until there are flags set or buffer is ready
492 		 * to consume more samples
493 		 */
494 		while ((sc->flags_pending == 0) &&
495 		    bcm2835_audio_buffer_should_sleep(ch)) {
496 			cv_wait_sig(&sc->worker_cv, &sc->lock);
497 		}
498 		flags = sc->flags_pending;
499 		/* Clear pending flags */
500 		sc->flags_pending = 0;
501 		BCM2835_AUDIO_UNLOCK(sc);
502 
503 		/* Requested to change parameters */
504 		if (flags & AUDIO_PARAMS) {
505 			BCM2835_AUDIO_LOCK(sc);
506 			speed = ch->spd;
507 			format = ch->fmt;
508 			volume = sc->volume;
509 			dest = sc->dest;
510 			BCM2835_AUDIO_UNLOCK(sc);
511 			if (ch->playback_state == PLAYBACK_IDLE)
512 				bcm2835_audio_update_params(sc, format, speed);
513 			bcm2835_audio_update_controls(sc, volume, dest);
514 		}
515 
516 		/* Requested to stop playback */
517 		if ((flags & AUDIO_STOP) &&
518 		    (ch->playback_state == PLAYBACK_PLAYING)) {
519 			bcm2835_audio_stop(ch);
520 			BCM2835_AUDIO_LOCK(sc);
521 			bcm2835_audio_reset_channel(&sc->pch);
522 			ch->playback_state = PLAYBACK_IDLE;
523 			BCM2835_AUDIO_UNLOCK(sc);
524 			continue;
525 		}
526 
527 		/* Requested to start playback */
528 		if ((flags & AUDIO_PLAY) &&
529 		    (ch->playback_state == PLAYBACK_IDLE)) {
530 			BCM2835_AUDIO_LOCK(sc);
531 			ch->playback_state = PLAYBACK_PLAYING;
532 			BCM2835_AUDIO_UNLOCK(sc);
533 			bcm2835_audio_start(ch);
534 		}
535 
536 		if (ch->playback_state == PLAYBACK_IDLE)
537 			continue;
538 
539 		if (sndbuf_getready(ch->buffer) == 0)
540 			continue;
541 
542 		count = sndbuf_getready(ch->buffer);
543 		size = sndbuf_getsize(ch->buffer);
544 		readyptr = sndbuf_getreadyptr(ch->buffer);
545 
546 		BCM2835_AUDIO_LOCK(sc);
547 		if (readyptr + count > size)
548 			count = size - readyptr;
549 		count = min(count, ch->available_space);
550 		count -= (count % VCHIQ_AUDIO_PACKET_SIZE);
551 		BCM2835_AUDIO_UNLOCK(sc);
552 
553 		if (count < VCHIQ_AUDIO_PACKET_SIZE)
554 			continue;
555 
556 		buf = (uint8_t*)sndbuf_getbuf(ch->buffer) + readyptr;
557 
558 		bcm2835_audio_write_samples(ch, buf, count);
559 		BCM2835_AUDIO_LOCK(sc);
560 		ch->unsubmittedptr = (ch->unsubmittedptr + count) % sndbuf_getsize(ch->buffer);
561 		ch->available_space -= count;
562 		ch->submitted_samples += count;
563 		KASSERT(ch->available_space >= 0, ("ch->available_space == %d\n", ch->available_space));
564 		BCM2835_AUDIO_UNLOCK(sc);
565 	}
566 
567 	BCM2835_AUDIO_LOCK(sc);
568 	sc->worker_state = WORKER_STOPPED;
569 	cv_signal(&sc->worker_cv);
570 	BCM2835_AUDIO_UNLOCK(sc);
571 
572 	kproc_exit(0);
573 }
574 
575 static void
576 bcm2835_audio_create_worker(struct bcm2835_audio_info *sc)
577 {
578 	struct proc *newp;
579 
580 	sc->worker_state = WORKER_RUNNING;
581 	if (kproc_create(bcm2835_audio_worker, (void*)sc, &newp, 0, 0,
582 	    "bcm2835_audio_worker") != 0) {
583 		printf("failed to create bcm2835_audio_worker\n");
584 	}
585 }
586 
587 /* -------------------------------------------------------------------- */
588 /* channel interface for VCHI audio */
589 static void *
590 bcmchan_init(kobj_t obj, void *devinfo, struct snd_dbuf *b, struct pcm_channel *c, int dir)
591 {
592 	struct bcm2835_audio_info *sc = devinfo;
593 	struct bcm2835_audio_chinfo *ch = &sc->pch;
594 	void *buffer;
595 
596 	if (dir == PCMDIR_REC)
597 		return NULL;
598 
599 	ch->parent = sc;
600 	ch->channel = c;
601 	ch->buffer = b;
602 
603 	/* default values */
604 	ch->spd = 44100;
605 	ch->fmt = SND_FORMAT(AFMT_S16_LE, 2, 0);
606 	ch->blksz = VCHIQ_AUDIO_PACKET_SIZE;
607 
608 	buffer = malloc(sc->bufsz, M_DEVBUF, M_WAITOK | M_ZERO);
609 
610 	if (sndbuf_setup(ch->buffer, buffer, sc->bufsz) != 0) {
611 		device_printf(sc->dev, "sndbuf_setup failed\n");
612 		free(buffer, M_DEVBUF);
613 		return NULL;
614 	}
615 
616 	BCM2835_AUDIO_LOCK(sc);
617 	bcm2835_worker_update_params(sc);
618 	BCM2835_AUDIO_UNLOCK(sc);
619 
620 	return ch;
621 }
622 
623 static int
624 bcmchan_free(kobj_t obj, void *data)
625 {
626 	struct bcm2835_audio_chinfo *ch = data;
627 	void *buffer;
628 
629 	buffer = sndbuf_getbuf(ch->buffer);
630 	if (buffer)
631 		free(buffer, M_DEVBUF);
632 
633 	return (0);
634 }
635 
636 static int
637 bcmchan_setformat(kobj_t obj, void *data, uint32_t format)
638 {
639 	struct bcm2835_audio_chinfo *ch = data;
640 	struct bcm2835_audio_info *sc = ch->parent;
641 
642 	BCM2835_AUDIO_LOCK(sc);
643 	ch->fmt = format;
644 	bcm2835_worker_update_params(sc);
645 	BCM2835_AUDIO_UNLOCK(sc);
646 
647 	return 0;
648 }
649 
650 static uint32_t
651 bcmchan_setspeed(kobj_t obj, void *data, uint32_t speed)
652 {
653 	struct bcm2835_audio_chinfo *ch = data;
654 	struct bcm2835_audio_info *sc = ch->parent;
655 
656 	BCM2835_AUDIO_LOCK(sc);
657 	ch->spd = speed;
658 	bcm2835_worker_update_params(sc);
659 	BCM2835_AUDIO_UNLOCK(sc);
660 
661 	return ch->spd;
662 }
663 
664 static uint32_t
665 bcmchan_setblocksize(kobj_t obj, void *data, uint32_t blocksize)
666 {
667 	struct bcm2835_audio_chinfo *ch = data;
668 
669 	return ch->blksz;
670 }
671 
672 static int
673 bcmchan_trigger(kobj_t obj, void *data, int go)
674 {
675 	struct bcm2835_audio_chinfo *ch = data;
676 	struct bcm2835_audio_info *sc = ch->parent;
677 
678 	if (!PCMTRIG_COMMON(go))
679 		return (0);
680 
681 	switch (go) {
682 	case PCMTRIG_START:
683 		/* kickstart data flow */
684 		chn_intr(sc->pch.channel);
685 		ch->submitted_samples = 0;
686 		ch->retrieved_samples = 0;
687 		bcm2835_worker_play_start(sc);
688 		break;
689 
690 	case PCMTRIG_STOP:
691 	case PCMTRIG_ABORT:
692 		bcm2835_worker_play_stop(sc);
693 		break;
694 
695 	default:
696 		break;
697 	}
698 	return 0;
699 }
700 
701 static uint32_t
702 bcmchan_getptr(kobj_t obj, void *data)
703 {
704 	struct bcm2835_audio_chinfo *ch = data;
705 	struct bcm2835_audio_info *sc = ch->parent;
706 	uint32_t ret;
707 
708 	BCM2835_AUDIO_LOCK(sc);
709 	ret = ch->unsubmittedptr;
710 	BCM2835_AUDIO_UNLOCK(sc);
711 
712 	return ret;
713 }
714 
715 static struct pcmchan_caps *
716 bcmchan_getcaps(kobj_t obj, void *data)
717 {
718 
719 	return &bcm2835_audio_playcaps;
720 }
721 
722 static kobj_method_t bcmchan_methods[] = {
723     	KOBJMETHOD(channel_init,		bcmchan_init),
724     	KOBJMETHOD(channel_free,		bcmchan_free),
725     	KOBJMETHOD(channel_setformat,		bcmchan_setformat),
726     	KOBJMETHOD(channel_setspeed,		bcmchan_setspeed),
727     	KOBJMETHOD(channel_setblocksize,	bcmchan_setblocksize),
728     	KOBJMETHOD(channel_trigger,		bcmchan_trigger),
729     	KOBJMETHOD(channel_getptr,		bcmchan_getptr),
730     	KOBJMETHOD(channel_getcaps,		bcmchan_getcaps),
731 	KOBJMETHOD_END
732 };
733 CHANNEL_DECLARE(bcmchan);
734 
735 /************************************************************/
736 
737 static int
738 bcmmix_init(struct snd_mixer *m)
739 {
740 
741 	mix_setdevs(m, SOUND_MASK_VOLUME);
742 
743 	return (0);
744 }
745 
746 static int
747 bcmmix_set(struct snd_mixer *m, unsigned dev, unsigned left, unsigned right)
748 {
749     	struct bcm2835_audio_info *sc = mix_getdevinfo(m);
750 
751 	switch (dev) {
752 	case SOUND_MIXER_VOLUME:
753 		BCM2835_AUDIO_LOCK(sc);
754 		sc->volume = left;
755 		bcm2835_worker_update_params(sc);
756 		BCM2835_AUDIO_UNLOCK(sc);
757 
758 		break;
759 
760 	default:
761 		break;
762 	}
763 
764     	return left | (left << 8);
765 }
766 
767 static kobj_method_t bcmmixer_methods[] = {
768     	KOBJMETHOD(mixer_init,		bcmmix_init),
769     	KOBJMETHOD(mixer_set,		bcmmix_set),
770 	KOBJMETHOD_END
771 };
772 
773 MIXER_DECLARE(bcmmixer);
774 
775 static int
776 sysctl_bcm2835_audio_dest(SYSCTL_HANDLER_ARGS)
777 {
778 	struct bcm2835_audio_info *sc = arg1;
779 	int val;
780 	int err;
781 
782 	val = sc->dest;
783 	err = sysctl_handle_int(oidp, &val, 0, req);
784 	if (err || !req->newptr) /* error || read request */
785 		return (err);
786 
787 	if ((val < 0) || (val > 2))
788 		return (EINVAL);
789 
790 	BCM2835_AUDIO_LOCK(sc);
791 	sc->dest = val;
792 	bcm2835_worker_update_params(sc);
793 	BCM2835_AUDIO_UNLOCK(sc);
794 
795 	if (bootverbose)
796 		device_printf(sc->dev, "destination set to %s\n", dest_description(val));
797 
798 	return (0);
799 }
800 
801 static void
802 vchi_audio_sysctl_init(struct bcm2835_audio_info *sc)
803 {
804 	struct sysctl_ctx_list *ctx;
805 	struct sysctl_oid *tree_node;
806 	struct sysctl_oid_list *tree;
807 
808 	/*
809 	 * Add system sysctl tree/handlers.
810 	 */
811 	ctx = device_get_sysctl_ctx(sc->dev);
812 	tree_node = device_get_sysctl_tree(sc->dev);
813 	tree = SYSCTL_CHILDREN(tree_node);
814 	SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "dest",
815 	    CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_NEEDGIANT, sc, sizeof(*sc),
816 	    sysctl_bcm2835_audio_dest, "IU", "audio destination, "
817 	    "0 - auto, 1 - headphones, 2 - HDMI");
818 	SYSCTL_ADD_UQUAD(ctx, tree, OID_AUTO, "callbacks",
819 			CTLFLAG_RD, &sc->pch.callbacks,
820 			"callbacks total");
821 	SYSCTL_ADD_UQUAD(ctx, tree, OID_AUTO, "submitted",
822 			CTLFLAG_RD, &sc->pch.submitted_samples,
823 			"last play submitted samples");
824 	SYSCTL_ADD_UQUAD(ctx, tree, OID_AUTO, "retrieved",
825 			CTLFLAG_RD, &sc->pch.retrieved_samples,
826 			"last play retrieved samples");
827 	SYSCTL_ADD_UQUAD(ctx, tree, OID_AUTO, "underruns",
828 			CTLFLAG_RD, &sc->pch.underruns,
829 			"callback underruns");
830 	SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "freebuffer",
831 			CTLFLAG_RD, &sc->pch.available_space,
832 			sc->pch.available_space, "callbacks total");
833 	SYSCTL_ADD_INT(ctx, tree, OID_AUTO, "starved",
834 			CTLFLAG_RD, &sc->pch.starved,
835 			sc->pch.starved, "number of starved conditions");
836 }
837 
838 static void
839 bcm2835_audio_identify(driver_t *driver, device_t parent)
840 {
841 
842 	BUS_ADD_CHILD(parent, 0, "pcm", 0);
843 }
844 
845 static int
846 bcm2835_audio_probe(device_t dev)
847 {
848 
849 	device_set_desc(dev, "VCHIQ audio");
850 	return (BUS_PROBE_DEFAULT);
851 }
852 
853 static void
854 bcm2835_audio_delayed_init(void *xsc)
855 {
856     	struct bcm2835_audio_info *sc;
857     	char status[SND_STATUSLEN];
858 
859 	sc = xsc;
860 
861 	config_intrhook_disestablish(&sc->intr_hook);
862 
863 	bcm2835_audio_init(sc);
864 	bcm2835_audio_open(sc);
865 	sc->volume = 75;
866 	sc->dest = DEST_AUTO;
867 
868     	if (mixer_init(sc->dev, &bcmmixer_class, sc)) {
869 		device_printf(sc->dev, "mixer_init failed\n");
870 		goto no;
871 	}
872 
873     	if (pcm_register(sc->dev, sc, 1, 0)) {
874 		device_printf(sc->dev, "pcm_register failed\n");
875 		goto no;
876 	}
877 
878 	pcm_addchan(sc->dev, PCMDIR_PLAY, &bcmchan_class, sc);
879     	snprintf(status, SND_STATUSLEN, "at VCHIQ");
880 	pcm_setstatus(sc->dev, status);
881 
882 	bcm2835_audio_reset_channel(&sc->pch);
883 	bcm2835_audio_create_worker(sc);
884 
885 	vchi_audio_sysctl_init(sc);
886 
887 no:
888 	;
889 }
890 
891 static int
892 bcm2835_audio_attach(device_t dev)
893 {
894     	struct bcm2835_audio_info *sc;
895 
896 	sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK | M_ZERO);
897 
898 	sc->dev = dev;
899 	sc->bufsz = VCHIQ_AUDIO_BUFFER_SIZE;
900 
901 	mtx_init(&sc->lock, device_get_nameunit(dev),
902 	    "bcm_audio_lock", MTX_DEF);
903 	cv_init(&sc->worker_cv, "worker_cv");
904 	sc->vchi_handle = VCHIQ_SERVICE_HANDLE_INVALID;
905 
906 	/*
907 	 * We need interrupts enabled for VCHI to work properly,
908 	 * so delay initialization until it happens.
909 	 */
910 	sc->intr_hook.ich_func = bcm2835_audio_delayed_init;
911 	sc->intr_hook.ich_arg = sc;
912 
913 	if (config_intrhook_establish(&sc->intr_hook) != 0)
914 		goto no;
915 
916     	return 0;
917 
918 no:
919     	return ENXIO;
920 }
921 
922 static int
923 bcm2835_audio_detach(device_t dev)
924 {
925 	int r;
926 	struct bcm2835_audio_info *sc;
927 	sc = pcm_getdevinfo(dev);
928 
929 	/* Stop worker thread */
930 	BCM2835_AUDIO_LOCK(sc);
931 	sc->worker_state = WORKER_STOPPING;
932 	cv_signal(&sc->worker_cv);
933 	/* Wait for thread to exit */
934 	while (sc->worker_state != WORKER_STOPPED)
935 		cv_wait_sig(&sc->worker_cv, &sc->lock);
936 	BCM2835_AUDIO_UNLOCK(sc);
937 
938 	r = pcm_unregister(dev);
939 	if (r)
940 		return r;
941 
942 	mtx_destroy(&sc->lock);
943 	cv_destroy(&sc->worker_cv);
944 
945 	bcm2835_audio_release(sc);
946 
947     	free(sc, M_DEVBUF);
948 
949 	return 0;
950 }
951 
952 static device_method_t bcm2835_audio_methods[] = {
953 	/* Device interface */
954 	DEVMETHOD(device_identify,	bcm2835_audio_identify),
955 	DEVMETHOD(device_probe,		bcm2835_audio_probe),
956 	DEVMETHOD(device_attach,	bcm2835_audio_attach),
957 	DEVMETHOD(device_detach,	bcm2835_audio_detach),
958 	{ 0, 0 }
959 };
960 
961 static driver_t bcm2835_audio_driver = {
962 	"pcm",
963 	bcm2835_audio_methods,
964 	PCM_SOFTC_SIZE,
965 };
966 
967 DRIVER_MODULE(bcm2835_audio, vchiq, bcm2835_audio_driver, 0, 0);
968 MODULE_DEPEND(bcm2835_audio, sound, SOUND_MINVER, SOUND_PREFVER, SOUND_MAXVER);
969 MODULE_DEPEND(bcm2835_audio, vchiq, 1, 1, 1);
970 MODULE_VERSION(bcm2835_audio, 1);
971