feeder.c revision 66308 
1/*
2 * Copyright (c) 1999 Cameron Grant <gandalf@vilnya.demon.co.uk>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/dev/sound/pcm/feeder.c 66308 2000-09-23 22:11:32Z cg $
27 */
28
29#include <dev/sound/pcm/sound.h>
30
31#define MAXFEEDERS 	256
32#undef FEEDER_DEBUG
33
34struct feedertab_entry {
35	SLIST_ENTRY(feedertab_entry) link;
36	pcm_feeder *feeder;
37	struct pcm_feederdesc *desc;
38
39	int idx;
40};
41static SLIST_HEAD(, feedertab_entry) feedertab;
42
43/*****************************************************************************/
44
45void
46feeder_register(void *p)
47{
48	pcm_feeder *f = p;
49	struct feedertab_entry *fte;
50	static int feedercnt = 0;
51	int i;
52
53	if (feedercnt == 0) {
54		if (f->desc)
55			panic("FIRST FEEDER NOT ROOT: %s\n", f->name);
56		SLIST_INIT(&feedertab);
57		fte = malloc(sizeof(*fte), M_DEVBUF, M_NOWAIT);
58		fte->feeder = f;
59		fte->desc = NULL;
60		fte->idx = feedercnt;
61		SLIST_INSERT_HEAD(&feedertab, fte, link);
62		feedercnt++;
63		return;
64	}
65	/* printf("installing feeder: %s\n", f->name); */
66
67	i = 0;
68	while ((feedercnt < MAXFEEDERS) && (f->desc[i].type > 0)) {
69		fte = malloc(sizeof(*fte), M_DEVBUF, M_NOWAIT);
70		fte->feeder = f;
71		fte->desc = &f->desc[i];
72		fte->idx = feedercnt;
73		fte->desc->idx = feedercnt;
74		SLIST_INSERT_HEAD(&feedertab, fte, link);
75		i++;
76	}
77	feedercnt++;
78	if (feedercnt >= MAXFEEDERS)
79		printf("MAXFEEDERS exceeded\n");
80}
81
82static int
83cmpdesc(struct pcm_feederdesc *n, struct pcm_feederdesc *m)
84{
85	return ((n->type == m->type) &&
86		((n->in == 0) || (n->in == m->in)) &&
87		((n->out == 0) || (n->out == m->out)) &&
88		(n->flags == m->flags));
89}
90
91pcm_feeder *
92feeder_get(struct pcm_feederdesc *desc)
93{
94	struct feedertab_entry *fte;
95
96	SLIST_FOREACH(fte, &feedertab, link) {
97		if ((fte->desc != NULL) && cmpdesc(desc, fte->desc))
98			return fte->feeder;
99	}
100	return NULL;
101}
102
103pcm_feeder *
104feeder_getroot()
105{
106	struct feedertab_entry *fte;
107
108	SLIST_FOREACH(fte, &feedertab, link) {
109		if (fte->desc == NULL)
110			return fte->feeder;
111	}
112	return NULL;
113}
114
115int
116feeder_set(pcm_feeder *feeder, int what, int value)
117{
118	if (feeder->set)
119		return feeder->set(feeder, what, value);
120	else
121		return -1;
122}
123
124int
125chn_addfeeder(pcm_channel *c, pcm_feeder *f)
126{
127	pcm_feeder *nf;
128	struct pcm_feederdesc *nfdesc;
129
130	nf = malloc(sizeof(*nf), M_DEVBUF, M_NOWAIT);
131	nfdesc = malloc(sizeof(*nfdesc), M_DEVBUF, M_NOWAIT);
132        *nfdesc = *(f->desc);
133	*nf = *f;
134	nf->desc = nfdesc;
135	nf->source = c->feeder;
136	if (nf->init)
137		nf->init(nf);
138	if (nf->align > 0)
139		c->align += nf->align;
140	else if (nf->align < 0 && c->align < -nf->align)
141		c->align = -nf->align;
142
143	c->feeder = nf;
144
145	return 0;
146}
147
148int
149chn_removefeeder(pcm_channel *c)
150{
151	pcm_feeder *f;
152
153	if (c->feeder->source == NULL)
154		return -1;
155	f = c->feeder->source;
156	if (c->feeder->free)
157		c->feeder->free(c->feeder);
158	free(c->feeder->desc, M_DEVBUF);
159	free(c->feeder, M_DEVBUF);
160	c->feeder = f;
161	return 0;
162}
163
164pcm_feeder *
165chn_findfeeder(pcm_channel *c, u_int32_t type)
166{
167	pcm_feeder *f;
168
169	f = c->feeder;
170	while (f != NULL) {
171		if (f->desc->type == type)
172			return f;
173		f = f->source;
174	}
175	return NULL;
176}
177
178static int
179chainok(pcm_feeder *test, pcm_feeder *stop)
180{
181	u_int32_t visited[MAXFEEDERS / 32];
182	u_int32_t idx, mask;
183
184	bzero(visited, sizeof(visited));
185	while (test && (test != stop)) {
186		idx = test->desc->idx;
187		if (idx < 0)
188			panic("bad idx %d", idx);
189		if (idx >= MAXFEEDERS)
190			panic("bad idx %d", idx);
191		mask = 1 << (idx & 31);
192		idx >>= 5;
193		if (visited[idx] & mask)
194			return 0;
195		visited[idx] |= mask;
196		test = test->source;
197	}
198	return 1;
199}
200
201static pcm_feeder *
202feeder_fmtchain(u_int32_t *to, pcm_feeder *source, pcm_feeder *stop, int maxdepth)
203{
204	struct feedertab_entry *fte;
205	pcm_feeder *try, *ret;
206	struct pcm_feederdesc *trydesc;
207
208	/* printf("trying %s...\n", source->name); */
209	if (fmtvalid(source->desc->out, to)) {
210		/* printf("got it\n"); */
211		return source;
212	}
213
214	if (maxdepth < 0)
215		return NULL;
216
217	try = malloc(sizeof(*try), M_DEVBUF, M_NOWAIT);
218	trydesc = malloc(sizeof(*trydesc), M_DEVBUF, M_NOWAIT);
219	trydesc->type = FEEDER_FMT;
220	trydesc->in = source->desc->out;
221	trydesc->out = 0;
222	trydesc->flags = 0;
223	trydesc->idx = -1;
224
225	SLIST_FOREACH(fte, &feedertab, link) {
226		if ((fte->desc) && (fte->desc->in == source->desc->out)) {
227			*try = *(fte->feeder);
228			try->source = source;
229			try->desc = trydesc;
230			trydesc->out = fte->desc->out;
231			trydesc->idx = fte->idx;
232			ret = chainok(try, stop)? feeder_fmtchain(to, try, stop, maxdepth - 1) : NULL;
233			if (ret != NULL)
234				return ret;
235		}
236	}
237	free(try, M_DEVBUF);
238	free(trydesc, M_DEVBUF);
239	/* printf("giving up %s...\n", source->name); */
240	return NULL;
241}
242
243u_int32_t
244chn_fmtchain(pcm_channel *c, u_int32_t *to)
245{
246	pcm_feeder *try, *stop;
247	int max;
248
249	stop = c->feeder;
250	try = NULL;
251	max = 0;
252	while (try == NULL && max < 8) {
253		try = feeder_fmtchain(to, c->feeder, stop, max);
254		max++;
255	}
256	if (try == NULL)
257		return 0;
258	c->feeder = try;
259	c->align = 0;
260#ifdef FEEDER_DEBUG
261	printf("chain: ");
262#endif
263	while (try && (try != stop)) {
264#ifdef FEEDER_DEBUG
265		printf("%s [%d]", try->name, try->desc->idx);
266		if (try->source)
267			printf(" -> ");
268#endif
269		if (try->init)
270			try->init(try);
271		if (try->align > 0)
272			c->align += try->align;
273		else if (try->align < 0 && c->align < -try->align)
274			c->align = -try->align;
275		try = try->source;
276	}
277#ifdef FEEDER_DEBUG
278	printf("%s [%d]\n", try->name, try->desc->idx);
279#endif
280	return c->feeder->desc->out;
281}
282
283/*****************************************************************************/
284
285static int
286feed_root(pcm_feeder *feeder, pcm_channel *ch, u_int8_t *buffer, u_int32_t count, struct uio *stream)
287{
288	int ret, s;
289
290	KASSERT(count, ("feed_root: count == 0"));
291	count &= ~((1 << ch->align) - 1);
292	KASSERT(count, ("feed_root: aligned count == 0 (align = %d)", ch->align));
293
294	s = spltty();
295	count = min(count, stream->uio_resid);
296	if (count) {
297		ret = uiomove(buffer, count, stream);
298		KASSERT(ret == 0, ("feed_root: uiomove failed"));
299	}
300	splx(s);
301
302	return count;
303}
304static pcm_feeder feeder_root = {
305	"root",
306	0,
307	NULL,
308	NULL,
309	NULL,
310	NULL,
311	feed_root,
312};
313SYSINIT(feeder_root, SI_SUB_DRIVERS, SI_ORDER_FIRST, feeder_register, &feeder_root);
314
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318