1 /* pcm.c
2 **
3 ** Copyright 2011, The Android Open Source Project
4 **
5 ** Redistribution and use in source and binary forms, with or without
6 ** modification, are permitted provided that the following conditions are met:
7 ** * Redistributions of source code must retain the above copyright
8 ** notice, this list of conditions and the following disclaimer.
9 ** * 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 ** * Neither the name of The Android Open Source Project nor the names of
13 ** its contributors may be used to endorse or promote products derived
14 ** from this software without specific prior written permission.
15 **
16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND
17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE
20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
26 ** DAMAGE.
27 */
28
29 #include <stdbool.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <fcntl.h>
33 #include <stdarg.h>
34 #include <string.h>
35 #include <errno.h>
36 #include <unistd.h>
37 #include <poll.h>
38
39 #include <sys/ioctl.h>
40 #include <sys/mman.h>
41 #include <sys/time.h>
42 #include <limits.h>
43
44 #include <linux/ioctl.h>
45 #define __force
46 #define __bitwise
47 #define __user
48 #include <sound/asound.h>
49
50 #include <tinyalsa/asoundlib.h>
51 #include "pcm_io.h"
52 #include "snd_utils.h"
53
54 enum {
55 PCM_NODE_TYPE_HW = 0,
56 PCM_NODE_TYPE_PLUGIN,
57 };
58
59 #define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL
60
61 /* Logs information into a string; follows snprintf() in that
62 * offset may be greater than size, and though no characters are copied
63 * into string, characters are still counted into offset. */
64 #define STRLOG(string, offset, size, ...) \
65 do { int temp, clipoffset = offset > size ? size : offset; \
66 temp = snprintf(string + clipoffset, size - clipoffset, __VA_ARGS__); \
67 if (temp > 0) offset += temp; } while (0)
68
69 #ifndef ARRAY_SIZE
70 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
71 #endif
72
73 /* refer to SNDRV_PCM_ACCESS_##index in sound/asound.h. */
74 static const char * const access_lookup[] = {
75 "MMAP_INTERLEAVED",
76 "MMAP_NONINTERLEAVED",
77 "MMAP_COMPLEX",
78 "RW_INTERLEAVED",
79 "RW_NONINTERLEAVED",
80 };
81
82 /* refer to SNDRV_PCM_FORMAT_##index in sound/asound.h. */
83 static const char * const format_lookup[] = {
84 /*[0] =*/ "S8",
85 "U8",
86 "S16_LE",
87 "S16_BE",
88 "U16_LE",
89 "U16_BE",
90 "S24_LE",
91 "S24_BE",
92 "U24_LE",
93 "U24_BE",
94 "S32_LE",
95 "S32_BE",
96 "U32_LE",
97 "U32_BE",
98 "FLOAT_LE",
99 "FLOAT_BE",
100 "FLOAT64_LE",
101 "FLOAT64_BE",
102 "IEC958_SUBFRAME_LE",
103 "IEC958_SUBFRAME_BE",
104 "MU_LAW",
105 "A_LAW",
106 "IMA_ADPCM",
107 "MPEG",
108 /*[24] =*/ "GSM",
109 /* gap */
110 [31] = "SPECIAL",
111 "S24_3LE",
112 "S24_3BE",
113 "U24_3LE",
114 "U24_3BE",
115 "S20_3LE",
116 "S20_3BE",
117 "U20_3LE",
118 "U20_3BE",
119 "S18_3LE",
120 "S18_3BE",
121 "U18_3LE",
122 /*[43] =*/ "U18_3BE",
123 #if 0
124 /* recent additions, may not be present on local asound.h */
125 "G723_24",
126 "G723_24_1B",
127 "G723_40",
128 "G723_40_1B",
129 "DSD_U8",
130 "DSD_U16_LE",
131 #endif
132 };
133
134 extern struct pcm_ops hw_ops;
135 extern struct pcm_ops plug_ops;
136
137 /* refer to SNDRV_PCM_SUBFORMAT_##index in sound/asound.h. */
138 static const char * const subformat_lookup[] = {
139 "STD",
140 };
141
param_is_mask(int p)142 static inline int param_is_mask(int p)
143 {
144 return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) &&
145 (p <= SNDRV_PCM_HW_PARAM_LAST_MASK);
146 }
147
param_is_interval(int p)148 static inline int param_is_interval(int p)
149 {
150 return (p >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL) &&
151 (p <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL);
152 }
153
param_to_interval(struct snd_pcm_hw_params * p,int n)154 static inline struct snd_interval *param_to_interval(struct snd_pcm_hw_params *p, int n)
155 {
156 return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]);
157 }
158
param_to_mask(struct snd_pcm_hw_params * p,int n)159 static inline struct snd_mask *param_to_mask(struct snd_pcm_hw_params *p, int n)
160 {
161 return &(p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK]);
162 }
163
param_set_mask(struct snd_pcm_hw_params * p,int n,unsigned int bit)164 static void param_set_mask(struct snd_pcm_hw_params *p, int n, unsigned int bit)
165 {
166 if (bit >= SNDRV_MASK_MAX)
167 return;
168 if (param_is_mask(n)) {
169 struct snd_mask *m = param_to_mask(p, n);
170 m->bits[0] = 0;
171 m->bits[1] = 0;
172 m->bits[bit >> 5] |= (1 << (bit & 31));
173 }
174 }
175
param_set_min(struct snd_pcm_hw_params * p,int n,unsigned int val)176 static void param_set_min(struct snd_pcm_hw_params *p, int n, unsigned int val)
177 {
178 if (param_is_interval(n)) {
179 struct snd_interval *i = param_to_interval(p, n);
180 i->min = val;
181 }
182 }
183
param_get_min(struct snd_pcm_hw_params * p,int n)184 static unsigned int param_get_min(struct snd_pcm_hw_params *p, int n)
185 {
186 if (param_is_interval(n)) {
187 struct snd_interval *i = param_to_interval(p, n);
188 return i->min;
189 }
190 return 0;
191 }
192
param_set_max(struct snd_pcm_hw_params * p,int n,unsigned int val)193 static void param_set_max(struct snd_pcm_hw_params *p, int n, unsigned int val)
194 {
195 if (param_is_interval(n)) {
196 struct snd_interval *i = param_to_interval(p, n);
197 i->max = val;
198 }
199 }
200
param_get_max(struct snd_pcm_hw_params * p,int n)201 static unsigned int param_get_max(struct snd_pcm_hw_params *p, int n)
202 {
203 if (param_is_interval(n)) {
204 struct snd_interval *i = param_to_interval(p, n);
205 return i->max;
206 }
207 return 0;
208 }
209
param_set_int(struct snd_pcm_hw_params * p,int n,unsigned int val)210 static void param_set_int(struct snd_pcm_hw_params *p, int n, unsigned int val)
211 {
212 if (param_is_interval(n)) {
213 struct snd_interval *i = param_to_interval(p, n);
214 i->min = val;
215 i->max = val;
216 i->integer = 1;
217 }
218 }
219
param_get_int(struct snd_pcm_hw_params * p,int n)220 static unsigned int param_get_int(struct snd_pcm_hw_params *p, int n)
221 {
222 if (param_is_interval(n)) {
223 struct snd_interval *i = param_to_interval(p, n);
224 if (i->integer)
225 return i->max;
226 }
227 return 0;
228 }
229
param_init(struct snd_pcm_hw_params * p)230 static void param_init(struct snd_pcm_hw_params *p)
231 {
232 int n;
233
234 memset(p, 0, sizeof(*p));
235 for (n = SNDRV_PCM_HW_PARAM_FIRST_MASK;
236 n <= SNDRV_PCM_HW_PARAM_LAST_MASK; n++) {
237 struct snd_mask *m = param_to_mask(p, n);
238 m->bits[0] = ~0;
239 m->bits[1] = ~0;
240 }
241 for (n = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL;
242 n <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; n++) {
243 struct snd_interval *i = param_to_interval(p, n);
244 i->min = 0;
245 i->max = ~0;
246 }
247 p->rmask = ~0U;
248 p->cmask = 0;
249 p->info = ~0U;
250 }
251
252 #define PCM_ERROR_MAX 128
253
254 struct pcm {
255 int fd;
256 unsigned int flags;
257 bool running:1;
258 bool prepared:1;
259 int underruns;
260 unsigned int buffer_size;
261 unsigned long boundary;
262 char error[PCM_ERROR_MAX];
263 struct pcm_config config;
264 struct snd_pcm_mmap_status *mmap_status;
265 struct snd_pcm_mmap_control *mmap_control;
266 struct snd_pcm_sync_ptr *sync_ptr;
267 void *mmap_buffer;
268 unsigned int noirq_frames_per_msec;
269 int wait_for_avail_min;
270 unsigned int subdevice;
271
272 struct pcm_ops *ops;
273 void *data;
274 void *snd_node;
275 };
276
pcm_get_buffer_size(struct pcm * pcm)277 unsigned int pcm_get_buffer_size(struct pcm *pcm)
278 {
279 return pcm->buffer_size;
280 }
281
pcm_get_error(struct pcm * pcm)282 const char* pcm_get_error(struct pcm *pcm)
283 {
284 return pcm->error;
285 }
286
pcm_get_subdevice(struct pcm * pcm)287 unsigned int pcm_get_subdevice(struct pcm *pcm)
288 {
289 return pcm->subdevice;
290 }
291
oops(struct pcm * pcm,int e,const char * fmt,...)292 static int oops(struct pcm *pcm, int e, const char *fmt, ...)
293 {
294 va_list ap;
295 int sz;
296
297 va_start(ap, fmt);
298 vsnprintf(pcm->error, PCM_ERROR_MAX, fmt, ap);
299 va_end(ap);
300 sz = strlen(pcm->error);
301
302 if (e)
303 snprintf(pcm->error + sz, PCM_ERROR_MAX - sz,
304 ": %s", strerror(e));
305 return -1;
306 }
307
pcm_format_to_alsa(enum pcm_format format)308 static unsigned int pcm_format_to_alsa(enum pcm_format format)
309 {
310 switch (format) {
311 case PCM_FORMAT_S32_LE:
312 return SNDRV_PCM_FORMAT_S32_LE;
313 case PCM_FORMAT_S8:
314 return SNDRV_PCM_FORMAT_S8;
315 case PCM_FORMAT_S24_3LE:
316 return SNDRV_PCM_FORMAT_S24_3LE;
317 case PCM_FORMAT_S24_LE:
318 return SNDRV_PCM_FORMAT_S24_LE;
319 default:
320 case PCM_FORMAT_S16_LE:
321 return SNDRV_PCM_FORMAT_S16_LE;
322 };
323 }
324
pcm_format_to_bits(enum pcm_format format)325 unsigned int pcm_format_to_bits(enum pcm_format format)
326 {
327 switch (format) {
328 case PCM_FORMAT_S32_LE:
329 case PCM_FORMAT_S24_LE:
330 return 32;
331 case PCM_FORMAT_S24_3LE:
332 return 24;
333 default:
334 case PCM_FORMAT_S16_LE:
335 return 16;
336 };
337 }
338
pcm_bytes_to_frames(struct pcm * pcm,unsigned int bytes)339 unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes)
340 {
341 return bytes / (pcm->config.channels *
342 (pcm_format_to_bits(pcm->config.format) >> 3));
343 }
344
pcm_frames_to_bytes(struct pcm * pcm,unsigned int frames)345 unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames)
346 {
347 return frames * pcm->config.channels *
348 (pcm_format_to_bits(pcm->config.format) >> 3);
349 }
350
pcm_sync_ptr(struct pcm * pcm,int flags)351 static int pcm_sync_ptr(struct pcm *pcm, int flags) {
352 if (pcm->sync_ptr) {
353 pcm->sync_ptr->flags = flags;
354 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SYNC_PTR,
355 pcm->sync_ptr) < 0)
356 return -1;
357 }
358 return 0;
359 }
360
pcm_hw_mmap_status(struct pcm * pcm)361 static int pcm_hw_mmap_status(struct pcm *pcm) {
362
363 if (pcm->sync_ptr)
364 return 0;
365
366 int page_size = sysconf(_SC_PAGE_SIZE);
367 pcm->mmap_status = pcm->ops->mmap(pcm->data, NULL, page_size, PROT_READ, MAP_FILE | MAP_SHARED,
368 SNDRV_PCM_MMAP_OFFSET_STATUS);
369 if (pcm->mmap_status == MAP_FAILED)
370 pcm->mmap_status = NULL;
371 if (!pcm->mmap_status)
372 goto mmap_error;
373
374 pcm->mmap_control = pcm->ops->mmap(pcm->data, NULL, page_size, PROT_READ | PROT_WRITE,
375 MAP_FILE | MAP_SHARED, SNDRV_PCM_MMAP_OFFSET_CONTROL);
376 if (pcm->mmap_control == MAP_FAILED)
377 pcm->mmap_control = NULL;
378 if (!pcm->mmap_control) {
379 pcm->ops->munmap(pcm->data, pcm->mmap_status, page_size);
380 pcm->mmap_status = NULL;
381 goto mmap_error;
382 }
383 if (pcm->flags & PCM_MMAP)
384 pcm->mmap_control->avail_min = pcm->config.avail_min;
385 else
386 pcm->mmap_control->avail_min = 1;
387
388 return 0;
389
390 mmap_error:
391
392 pcm->sync_ptr = calloc(1, sizeof(*pcm->sync_ptr));
393 if (!pcm->sync_ptr)
394 return -ENOMEM;
395 pcm->mmap_status = &pcm->sync_ptr->s.status;
396 pcm->mmap_control = &pcm->sync_ptr->c.control;
397 if (pcm->flags & PCM_MMAP)
398 pcm->mmap_control->avail_min = pcm->config.avail_min;
399 else
400 pcm->mmap_control->avail_min = 1;
401
402 pcm_sync_ptr(pcm, 0);
403
404 return 0;
405 }
406
pcm_hw_munmap_status(struct pcm * pcm)407 static void pcm_hw_munmap_status(struct pcm *pcm) {
408 if (pcm->sync_ptr) {
409 free(pcm->sync_ptr);
410 pcm->sync_ptr = NULL;
411 } else {
412 int page_size = sysconf(_SC_PAGE_SIZE);
413 if (pcm->mmap_status)
414 pcm->ops->munmap(pcm->data, pcm->mmap_status, page_size);
415 if (pcm->mmap_control)
416 pcm->ops->munmap(pcm->data, pcm->mmap_control, page_size);
417 }
418 pcm->mmap_status = NULL;
419 pcm->mmap_control = NULL;
420 }
421
pcm_areas_copy(struct pcm * pcm,unsigned int pcm_offset,char * buf,unsigned int src_offset,unsigned int frames)422 static int pcm_areas_copy(struct pcm *pcm, unsigned int pcm_offset,
423 char *buf, unsigned int src_offset,
424 unsigned int frames)
425 {
426 int size_bytes = pcm_frames_to_bytes(pcm, frames);
427 int pcm_offset_bytes = pcm_frames_to_bytes(pcm, pcm_offset);
428 int src_offset_bytes = pcm_frames_to_bytes(pcm, src_offset);
429
430 /* interleaved only atm */
431 if (pcm->flags & PCM_IN)
432 memcpy(buf + src_offset_bytes,
433 (char*)pcm->mmap_buffer + pcm_offset_bytes,
434 size_bytes);
435 else
436 memcpy((char*)pcm->mmap_buffer + pcm_offset_bytes,
437 buf + src_offset_bytes,
438 size_bytes);
439 return 0;
440 }
441
pcm_mmap_transfer_areas(struct pcm * pcm,char * buf,unsigned int offset,unsigned int size)442 static int pcm_mmap_transfer_areas(struct pcm *pcm, char *buf,
443 unsigned int offset, unsigned int size)
444 {
445 void *pcm_areas;
446 int commit;
447 unsigned int pcm_offset, frames, count = 0;
448
449 while (size > 0) {
450 frames = size;
451 pcm_mmap_begin(pcm, &pcm_areas, &pcm_offset, &frames);
452 pcm_areas_copy(pcm, pcm_offset, buf, offset, frames);
453 commit = pcm_mmap_commit(pcm, pcm_offset, frames);
454 if (commit < 0) {
455 oops(pcm, errno, "failed to commit %d frames\n", frames);
456 return commit;
457 }
458
459 offset += commit;
460 count += commit;
461 size -= commit;
462 }
463 return count;
464 }
465
pcm_get_htimestamp(struct pcm * pcm,unsigned int * avail,struct timespec * tstamp)466 int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail,
467 struct timespec *tstamp)
468 {
469 snd_pcm_sframes_t frames;
470 int rc;
471 snd_pcm_uframes_t hw_ptr;
472
473 if (!pcm_is_ready(pcm))
474 return -1;
475
476 rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_HWSYNC);
477 if (rc < 0)
478 return -1;
479
480 if ((pcm->mmap_status->state != PCM_STATE_RUNNING) &&
481 (pcm->mmap_status->state != PCM_STATE_DRAINING))
482 return -1;
483
484 *tstamp = pcm->mmap_status->tstamp;
485 if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0)
486 return -1;
487
488 hw_ptr = pcm->mmap_status->hw_ptr;
489 if (pcm->flags & PCM_IN)
490 frames = hw_ptr - pcm->mmap_control->appl_ptr;
491 else
492 frames = hw_ptr + (snd_pcm_uframes_t) pcm->buffer_size -
493 pcm->mmap_control->appl_ptr;
494
495 if (frames < 0)
496 frames += pcm->boundary;
497 else if (frames >= (snd_pcm_sframes_t) pcm->boundary)
498 frames -= pcm->boundary;
499
500 *avail = (unsigned int)frames;
501
502 return 0;
503 }
504
pcm_mmap_get_hw_ptr(struct pcm * pcm,unsigned int * hw_ptr,struct timespec * tstamp)505 int pcm_mmap_get_hw_ptr(struct pcm* pcm, unsigned int *hw_ptr, struct timespec *tstamp)
506 {
507 int frames;
508 int rc;
509
510 if (pcm == NULL || hw_ptr == NULL || tstamp == NULL)
511 return oops(pcm, EINVAL, "pcm %p, hw_ptr %p, tstamp %p", pcm, hw_ptr, tstamp);
512
513 if (!pcm_is_ready(pcm))
514 return oops(pcm, errno, "pcm_is_ready failed");
515
516 rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC);
517 if (rc < 0)
518 return oops(pcm, errno, "pcm_sync_ptr failed");
519
520 if (pcm->mmap_status == NULL)
521 return oops(pcm, EINVAL, "pcm %p, mmap_status is NULL", pcm);
522
523 if ((pcm->mmap_status->state != PCM_STATE_RUNNING) &&
524 (pcm->mmap_status->state != PCM_STATE_DRAINING))
525 return oops(pcm, ENOSYS, "invalid stream state %d", pcm->mmap_status->state);
526
527 *tstamp = pcm->mmap_status->tstamp;
528 if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0)
529 return oops(pcm, errno, "invalid time stamp");
530
531 *hw_ptr = pcm->mmap_status->hw_ptr;
532
533 return 0;
534 }
535
pcm_write(struct pcm * pcm,const void * data,unsigned int count)536 int pcm_write(struct pcm *pcm, const void *data, unsigned int count)
537 {
538 struct snd_xferi x;
539
540 if (pcm->flags & PCM_IN)
541 return -EINVAL;
542
543 x.buf = (void*)data;
544 x.frames = count / (pcm->config.channels *
545 pcm_format_to_bits(pcm->config.format) / 8);
546
547 for (;;) {
548 if (!pcm->running) {
549 int prepare_error = pcm_prepare(pcm);
550 if (prepare_error)
551 return prepare_error;
552 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x))
553 return oops(pcm, errno, "cannot write initial data");
554 pcm->running = true;
555 return 0;
556 }
557 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) {
558 pcm->prepared = false;
559 pcm->running = false;
560 if (errno == EPIPE) {
561 /* we failed to make our window -- try to restart if we are
562 * allowed to do so. Otherwise, simply allow the EPIPE error to
563 * propagate up to the app level */
564 pcm->underruns++;
565 if (pcm->flags & PCM_NORESTART)
566 return -EPIPE;
567 continue;
568 }
569 return oops(pcm, errno, "cannot write stream data");
570 }
571 return 0;
572 }
573 }
574
pcm_read(struct pcm * pcm,void * data,unsigned int count)575 int pcm_read(struct pcm *pcm, void *data, unsigned int count)
576 {
577 struct snd_xferi x;
578
579 if (!(pcm->flags & PCM_IN))
580 return -EINVAL;
581
582 x.buf = data;
583 x.frames = count / (pcm->config.channels *
584 pcm_format_to_bits(pcm->config.format) / 8);
585
586 for (;;) {
587 if (!pcm->running) {
588 if (pcm_start(pcm) < 0) {
589 fprintf(stderr, "start error");
590 return -errno;
591 }
592 }
593 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_READI_FRAMES, &x)) {
594 pcm->prepared = false;
595 pcm->running = false;
596 if (errno == EPIPE) {
597 /* we failed to make our window -- try to restart */
598 pcm->underruns++;
599 continue;
600 }
601 return oops(pcm, errno, "cannot read stream data");
602 }
603 return 0;
604 }
605 }
606
607 static struct pcm bad_pcm = {
608 .fd = -1,
609 };
610
pcm_params_get(unsigned int card,unsigned int device,unsigned int flags)611 struct pcm_params *pcm_params_get(unsigned int card, unsigned int device,
612 unsigned int flags)
613 {
614 struct snd_pcm_hw_params *params;
615 enum snd_node_type pcm_type;
616 struct pcm_ops *ops;
617 void *snd_node, *data;
618 int fd;
619
620 snd_node = snd_utils_get_dev_node(card, device, NODE_PCM);
621 pcm_type = snd_utils_get_node_type(snd_node);
622 if (pcm_type == SND_NODE_TYPE_PLUGIN)
623 ops = &plug_ops;
624 else
625 ops = &hw_ops;
626
627 fd = ops->open(card, device, flags, &data, snd_node);
628 if (fd < 0) {
629 fprintf(stderr, "cannot open device %u for card %u\n",
630 device, card);
631 goto err_open;
632 }
633
634 params = calloc(1, sizeof(struct snd_pcm_hw_params));
635 if (!params)
636 goto err_calloc;
637
638 param_init(params);
639 if (ops->ioctl(data, SNDRV_PCM_IOCTL_HW_REFINE, params)) {
640 fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno);
641 goto err_hw_refine;
642 }
643
644 snd_utils_put_dev_node(snd_node);
645 ops->close(data);
646
647 return (struct pcm_params *)params;
648
649 err_hw_refine:
650 free(params);
651 err_calloc:
652 ops->close(data);
653 err_open:
654 snd_utils_put_dev_node(snd_node);
655 return NULL;
656 }
657
pcm_params_free(struct pcm_params * pcm_params)658 void pcm_params_free(struct pcm_params *pcm_params)
659 {
660 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
661
662 if (params)
663 free(params);
664 }
665
pcm_param_to_alsa(enum pcm_param param)666 static int pcm_param_to_alsa(enum pcm_param param)
667 {
668 switch (param) {
669 case PCM_PARAM_ACCESS:
670 return SNDRV_PCM_HW_PARAM_ACCESS;
671 case PCM_PARAM_FORMAT:
672 return SNDRV_PCM_HW_PARAM_FORMAT;
673 case PCM_PARAM_SUBFORMAT:
674 return SNDRV_PCM_HW_PARAM_SUBFORMAT;
675 case PCM_PARAM_SAMPLE_BITS:
676 return SNDRV_PCM_HW_PARAM_SAMPLE_BITS;
677 break;
678 case PCM_PARAM_FRAME_BITS:
679 return SNDRV_PCM_HW_PARAM_FRAME_BITS;
680 break;
681 case PCM_PARAM_CHANNELS:
682 return SNDRV_PCM_HW_PARAM_CHANNELS;
683 break;
684 case PCM_PARAM_RATE:
685 return SNDRV_PCM_HW_PARAM_RATE;
686 break;
687 case PCM_PARAM_PERIOD_TIME:
688 return SNDRV_PCM_HW_PARAM_PERIOD_TIME;
689 break;
690 case PCM_PARAM_PERIOD_SIZE:
691 return SNDRV_PCM_HW_PARAM_PERIOD_SIZE;
692 break;
693 case PCM_PARAM_PERIOD_BYTES:
694 return SNDRV_PCM_HW_PARAM_PERIOD_BYTES;
695 break;
696 case PCM_PARAM_PERIODS:
697 return SNDRV_PCM_HW_PARAM_PERIODS;
698 break;
699 case PCM_PARAM_BUFFER_TIME:
700 return SNDRV_PCM_HW_PARAM_BUFFER_TIME;
701 break;
702 case PCM_PARAM_BUFFER_SIZE:
703 return SNDRV_PCM_HW_PARAM_BUFFER_SIZE;
704 break;
705 case PCM_PARAM_BUFFER_BYTES:
706 return SNDRV_PCM_HW_PARAM_BUFFER_BYTES;
707 break;
708 case PCM_PARAM_TICK_TIME:
709 return SNDRV_PCM_HW_PARAM_TICK_TIME;
710 break;
711
712 default:
713 return -1;
714 }
715 }
716
pcm_params_get_mask(const struct pcm_params * pcm_params,enum pcm_param param)717 struct pcm_mask *pcm_params_get_mask(const struct pcm_params *pcm_params,
718 enum pcm_param param)
719 {
720 int p;
721 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
722 if (params == NULL) {
723 return NULL;
724 }
725
726 p = pcm_param_to_alsa(param);
727 if (p < 0 || !param_is_mask(p)) {
728 return NULL;
729 }
730
731 return (struct pcm_mask *)param_to_mask(params, p);
732 }
733
pcm_params_get_min(const struct pcm_params * pcm_params,enum pcm_param param)734 unsigned int pcm_params_get_min(const struct pcm_params *pcm_params,
735 enum pcm_param param)
736 {
737 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
738 int p;
739
740 if (!params)
741 return 0;
742
743 p = pcm_param_to_alsa(param);
744 if (p < 0)
745 return 0;
746
747 return param_get_min(params, p);
748 }
749
pcm_params_set_min(struct pcm_params * pcm_params,enum pcm_param param,unsigned int val)750 void pcm_params_set_min(struct pcm_params *pcm_params,
751 enum pcm_param param, unsigned int val)
752 {
753 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
754 int p;
755
756 if (!params)
757 return;
758
759 p = pcm_param_to_alsa(param);
760 if (p < 0)
761 return;
762
763 param_set_min(params, p, val);
764 }
765
pcm_params_get_max(const struct pcm_params * pcm_params,enum pcm_param param)766 unsigned int pcm_params_get_max(const struct pcm_params *pcm_params,
767 enum pcm_param param)
768 {
769 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
770 int p;
771
772 if (!params)
773 return 0;
774
775 p = pcm_param_to_alsa(param);
776 if (p < 0)
777 return 0;
778
779 return param_get_max(params, p);
780 }
781
pcm_params_set_max(struct pcm_params * pcm_params,enum pcm_param param,unsigned int val)782 void pcm_params_set_max(struct pcm_params *pcm_params,
783 enum pcm_param param, unsigned int val)
784 {
785 struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params;
786 int p;
787
788 if (!params)
789 return;
790
791 p = pcm_param_to_alsa(param);
792 if (p < 0)
793 return;
794
795 param_set_max(params, p, val);
796 }
797
pcm_mask_test(struct pcm_mask * m,unsigned int index)798 static int pcm_mask_test(struct pcm_mask *m, unsigned int index)
799 {
800 const unsigned int bitshift = 5; /* for 32 bit integer */
801 const unsigned int bitmask = (1 << bitshift) - 1;
802 unsigned int element;
803
804 element = index >> bitshift;
805 if (element >= ARRAY_SIZE(m->bits))
806 return 0; /* for safety, but should never occur */
807 return (m->bits[element] >> (index & bitmask)) & 1;
808 }
809
pcm_mask_to_string(struct pcm_mask * m,char * string,unsigned int size,char * mask_name,const char * const * bit_array_name,size_t bit_array_size)810 static int pcm_mask_to_string(struct pcm_mask *m, char *string, unsigned int size,
811 char *mask_name,
812 const char * const *bit_array_name, size_t bit_array_size)
813 {
814 unsigned int i;
815 unsigned int offset = 0;
816
817 if (m == NULL)
818 return 0;
819 if (bit_array_size < 32) {
820 STRLOG(string, offset, size, "%12s:\t%#08x\n", mask_name, m->bits[0]);
821 } else { /* spans two or more bitfields, print with an array index */
822 for (i = 0; i < (bit_array_size + 31) >> 5; ++i) {
823 STRLOG(string, offset, size, "%9s[%d]:\t%#08x\n",
824 mask_name, i, m->bits[i]);
825 }
826 }
827 for (i = 0; i < bit_array_size; ++i) {
828 if (pcm_mask_test(m, i)) {
829 STRLOG(string, offset, size, "%12s \t%s\n", "", bit_array_name[i]);
830 }
831 }
832 return offset;
833 }
834
pcm_params_to_string(struct pcm_params * params,char * string,unsigned int size)835 int pcm_params_to_string(struct pcm_params *params, char *string, unsigned int size)
836 {
837 struct pcm_mask *m;
838 unsigned int min, max;
839 unsigned int clipoffset, offset;
840
841 m = pcm_params_get_mask(params, PCM_PARAM_ACCESS);
842 offset = pcm_mask_to_string(m, string, size,
843 "Access", access_lookup, ARRAY_SIZE(access_lookup));
844 m = pcm_params_get_mask(params, PCM_PARAM_FORMAT);
845 clipoffset = offset > size ? size : offset;
846 offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset,
847 "Format", format_lookup, ARRAY_SIZE(format_lookup));
848 m = pcm_params_get_mask(params, PCM_PARAM_SUBFORMAT);
849 clipoffset = offset > size ? size : offset;
850 offset += pcm_mask_to_string(m, string + clipoffset, size - clipoffset,
851 "Subformat", subformat_lookup, ARRAY_SIZE(subformat_lookup));
852 min = pcm_params_get_min(params, PCM_PARAM_RATE);
853 max = pcm_params_get_max(params, PCM_PARAM_RATE);
854 STRLOG(string, offset, size, " Rate:\tmin=%uHz\tmax=%uHz\n", min, max);
855 min = pcm_params_get_min(params, PCM_PARAM_CHANNELS);
856 max = pcm_params_get_max(params, PCM_PARAM_CHANNELS);
857 STRLOG(string, offset, size, " Channels:\tmin=%u\t\tmax=%u\n", min, max);
858 min = pcm_params_get_min(params, PCM_PARAM_SAMPLE_BITS);
859 max = pcm_params_get_max(params, PCM_PARAM_SAMPLE_BITS);
860 STRLOG(string, offset, size, " Sample bits:\tmin=%u\t\tmax=%u\n", min, max);
861 min = pcm_params_get_min(params, PCM_PARAM_PERIOD_SIZE);
862 max = pcm_params_get_max(params, PCM_PARAM_PERIOD_SIZE);
863 STRLOG(string, offset, size, " Period size:\tmin=%u\t\tmax=%u\n", min, max);
864 min = pcm_params_get_min(params, PCM_PARAM_PERIODS);
865 max = pcm_params_get_max(params, PCM_PARAM_PERIODS);
866 STRLOG(string, offset, size, "Period count:\tmin=%u\t\tmax=%u\n", min, max);
867 return offset;
868 }
869
pcm_params_format_test(struct pcm_params * params,enum pcm_format format)870 int pcm_params_format_test(struct pcm_params *params, enum pcm_format format)
871 {
872 unsigned int alsa_format = pcm_format_to_alsa(format);
873
874 if (alsa_format == SNDRV_PCM_FORMAT_S16_LE && format != PCM_FORMAT_S16_LE)
875 return 0; /* caution: format not recognized is equivalent to S16_LE */
876 return pcm_mask_test(pcm_params_get_mask(params, PCM_PARAM_FORMAT), alsa_format);
877 }
878
pcm_close(struct pcm * pcm)879 int pcm_close(struct pcm *pcm)
880 {
881 if (pcm == &bad_pcm)
882 return 0;
883
884 pcm_hw_munmap_status(pcm);
885
886 if (pcm->flags & PCM_MMAP) {
887 pcm_stop(pcm);
888 pcm->ops->munmap(pcm->data, pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
889 }
890
891 if (pcm->data)
892 pcm->ops->close(pcm->data);
893 if (pcm->snd_node)
894 snd_utils_put_dev_node(pcm->snd_node);
895
896 pcm->prepared = false;
897 pcm->running = false;
898 pcm->buffer_size = 0;
899 pcm->fd = -1;
900 free(pcm);
901 return 0;
902 }
903
pcm_open(unsigned int card,unsigned int device,unsigned int flags,struct pcm_config * config)904 struct pcm *pcm_open(unsigned int card, unsigned int device,
905 unsigned int flags, struct pcm_config *config)
906 {
907 struct pcm *pcm;
908 struct snd_pcm_info info;
909 struct snd_pcm_hw_params params;
910 struct snd_pcm_sw_params sparams;
911 int rc, pcm_type;
912
913 if (!config) {
914 return &bad_pcm; /* TODO: could support default config here */
915 }
916 pcm = calloc(1, sizeof(struct pcm));
917 if (!pcm) {
918 oops(&bad_pcm, ENOMEM, "can't allocate PCM object");
919 return &bad_pcm; /* TODO: could support default config here */
920 }
921
922 pcm->config = *config;
923 pcm->flags = flags;
924
925 pcm->snd_node = snd_utils_get_dev_node(card, device, NODE_PCM);
926 pcm_type = snd_utils_get_node_type(pcm->snd_node);
927 if (pcm_type == SND_NODE_TYPE_PLUGIN)
928 pcm->ops = &plug_ops;
929 else
930 pcm->ops = &hw_ops;
931
932 pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, pcm->snd_node);
933 if (pcm->fd < 0) {
934 oops(&bad_pcm, errno, "cannot open device %u for card %u",
935 device, card);
936 goto fail_open;
937 }
938
939 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_INFO, &info)) {
940 oops(&bad_pcm, errno, "cannot get info");
941 goto fail_close;
942 }
943 pcm->subdevice = info.subdevice;
944
945 param_init(¶ms);
946 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_FORMAT,
947 pcm_format_to_alsa(config->format));
948 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_SUBFORMAT,
949 SNDRV_PCM_SUBFORMAT_STD);
950 param_set_min(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size);
951 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_SAMPLE_BITS,
952 pcm_format_to_bits(config->format));
953 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_FRAME_BITS,
954 pcm_format_to_bits(config->format) * config->channels);
955 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_CHANNELS,
956 config->channels);
957 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS, config->period_count);
958 param_set_int(¶ms, SNDRV_PCM_HW_PARAM_RATE, config->rate);
959
960 if (flags & PCM_NOIRQ) {
961 if (!(flags & PCM_MMAP)) {
962 oops(&bad_pcm, EINVAL, "noirq only currently supported with mmap().");
963 goto fail_close;
964 }
965
966 params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP;
967 pcm->noirq_frames_per_msec = config->rate / 1000;
968 }
969
970 if (flags & PCM_MMAP)
971 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS,
972 SNDRV_PCM_ACCESS_MMAP_INTERLEAVED);
973 else
974 param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS,
975 SNDRV_PCM_ACCESS_RW_INTERLEAVED);
976
977 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_HW_PARAMS, ¶ms)) {
978 oops(&bad_pcm, errno, "cannot set hw params");
979 goto fail_close;
980 }
981
982 /* get our refined hw_params */
983 config->period_size = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
984 config->period_count = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS);
985 pcm->buffer_size = config->period_count * config->period_size;
986
987 if (flags & PCM_MMAP) {
988 pcm->mmap_buffer = pcm->ops->mmap(pcm->data, NULL,
989 pcm_frames_to_bytes(pcm, pcm->buffer_size),
990 PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, 0);
991 if (pcm->mmap_buffer == MAP_FAILED) {
992 oops(&bad_pcm, errno, "failed to mmap buffer %d bytes\n",
993 pcm_frames_to_bytes(pcm, pcm->buffer_size));
994 goto fail_close;
995 }
996 }
997
998 memset(&sparams, 0, sizeof(sparams));
999 sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE;
1000 sparams.period_step = 1;
1001
1002 if (!config->start_threshold) {
1003 if (pcm->flags & PCM_IN)
1004 pcm->config.start_threshold = sparams.start_threshold = 1;
1005 else
1006 pcm->config.start_threshold = sparams.start_threshold =
1007 config->period_count * config->period_size / 2;
1008 } else
1009 sparams.start_threshold = config->start_threshold;
1010
1011 /* pick a high stop threshold - todo: does this need further tuning */
1012 if (!config->stop_threshold) {
1013 if (pcm->flags & PCM_IN)
1014 pcm->config.stop_threshold = sparams.stop_threshold =
1015 config->period_count * config->period_size * 10;
1016 else
1017 pcm->config.stop_threshold = sparams.stop_threshold =
1018 config->period_count * config->period_size;
1019 }
1020 else
1021 sparams.stop_threshold = config->stop_threshold;
1022
1023 if (!pcm->config.avail_min) {
1024 if (pcm->flags & PCM_MMAP)
1025 pcm->config.avail_min = sparams.avail_min = pcm->config.period_size;
1026 else
1027 pcm->config.avail_min = sparams.avail_min = 1;
1028 } else
1029 sparams.avail_min = config->avail_min;
1030
1031 sparams.xfer_align = config->period_size / 2; /* needed for old kernels */
1032 sparams.silence_threshold = config->silence_threshold;
1033 sparams.silence_size = config->silence_size;
1034
1035 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) {
1036 oops(&bad_pcm, errno, "cannot set sw params");
1037 goto fail;
1038 }
1039 pcm->boundary = sparams.boundary;
1040
1041 rc = pcm_hw_mmap_status(pcm);
1042 if (rc < 0) {
1043 oops(&bad_pcm, errno, "mmap status failed");
1044 goto fail;
1045 }
1046
1047 #ifdef SNDRV_PCM_IOCTL_TTSTAMP
1048 if (pcm->flags & PCM_MONOTONIC) {
1049 int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC;
1050 rc = pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_TTSTAMP, &arg);
1051 if (rc < 0) {
1052 oops(&bad_pcm, errno, "cannot set timestamp type");
1053 goto fail;
1054 }
1055 }
1056 #endif
1057
1058 pcm->underruns = 0;
1059 return pcm;
1060
1061 fail:
1062 if (flags & PCM_MMAP)
1063 pcm->ops->munmap(pcm->data, pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size));
1064 fail_close:
1065 pcm->ops->close(pcm->data);
1066
1067 fail_open:
1068 snd_utils_put_dev_node(pcm->snd_node);
1069 free(pcm);
1070 return &bad_pcm;
1071 }
1072
pcm_is_ready(struct pcm * pcm)1073 int pcm_is_ready(struct pcm *pcm)
1074 {
1075 return pcm->fd >= 0;
1076 }
1077
pcm_prepare(struct pcm * pcm)1078 int pcm_prepare(struct pcm *pcm)
1079 {
1080 if (pcm->prepared)
1081 return 0;
1082
1083 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_PREPARE) < 0)
1084 return oops(pcm, errno, "cannot prepare channel");
1085
1086 pcm->prepared = true;
1087 return 0;
1088 }
1089
pcm_start(struct pcm * pcm)1090 int pcm_start(struct pcm *pcm)
1091 {
1092 int prepare_error = pcm_prepare(pcm);
1093 if (prepare_error)
1094 return prepare_error;
1095
1096 if (pcm->flags & PCM_MMAP)
1097 pcm_sync_ptr(pcm, 0);
1098
1099 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_START) < 0)
1100 return oops(pcm, errno, "cannot start channel");
1101
1102 pcm->running = true;
1103 return 0;
1104 }
1105
pcm_stop(struct pcm * pcm)1106 int pcm_stop(struct pcm *pcm)
1107 {
1108 if (pcm->ops->ioctl(pcm->data, SNDRV_PCM_IOCTL_DROP) < 0)
1109 return oops(pcm, errno, "cannot stop channel");
1110
1111 pcm->prepared = false;
1112 pcm->running = false;
1113 return 0;
1114 }
1115
pcm_mmap_playback_avail(struct pcm * pcm)1116 static inline long pcm_mmap_playback_avail(struct pcm *pcm)
1117 {
1118 long avail = pcm->mmap_status->hw_ptr + (unsigned long) pcm->buffer_size -
1119 pcm->mmap_control->appl_ptr;
1120
1121 if (avail < 0) {
1122 avail += pcm->boundary;
1123 } else if ((unsigned long) avail >= pcm->boundary) {
1124 avail -= pcm->boundary;
1125 }
1126
1127 return avail;
1128 }
1129
pcm_mmap_capture_avail(struct pcm * pcm)1130 static inline long pcm_mmap_capture_avail(struct pcm *pcm)
1131 {
1132 long avail = pcm->mmap_status->hw_ptr - pcm->mmap_control->appl_ptr;
1133 if (avail < 0) {
1134 avail += pcm->boundary;
1135 }
1136 return avail;
1137 }
1138
pcm_mmap_avail(struct pcm * pcm)1139 int pcm_mmap_avail(struct pcm *pcm)
1140 {
1141 pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC);
1142 if (pcm->flags & PCM_IN) {
1143 return (int) pcm_mmap_capture_avail(pcm);
1144 } else {
1145 return (int) pcm_mmap_playback_avail(pcm);
1146 }
1147 }
1148
pcm_mmap_appl_forward(struct pcm * pcm,int frames)1149 static void pcm_mmap_appl_forward(struct pcm *pcm, int frames)
1150 {
1151 unsigned long appl_ptr = pcm->mmap_control->appl_ptr;
1152 appl_ptr += frames;
1153
1154 /* check for boundary wrap */
1155 if (appl_ptr >= pcm->boundary) {
1156 appl_ptr -= pcm->boundary;
1157 }
1158 pcm->mmap_control->appl_ptr = appl_ptr;
1159 }
1160
pcm_mmap_begin(struct pcm * pcm,void ** areas,unsigned int * offset,unsigned int * frames)1161 int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset,
1162 unsigned int *frames)
1163 {
1164 unsigned int continuous, copy_frames, avail;
1165
1166 /* return the mmap buffer */
1167 *areas = pcm->mmap_buffer;
1168
1169 /* and the application offset in frames */
1170 *offset = pcm->mmap_control->appl_ptr % pcm->buffer_size;
1171
1172 avail = pcm_mmap_avail(pcm);
1173 if (avail > pcm->buffer_size)
1174 avail = pcm->buffer_size;
1175 continuous = pcm->buffer_size - *offset;
1176
1177 /* we can only copy frames if the are availabale and continuos */
1178 copy_frames = *frames;
1179 if (copy_frames > avail)
1180 copy_frames = avail;
1181 if (copy_frames > continuous)
1182 copy_frames = continuous;
1183 *frames = copy_frames;
1184
1185 return 0;
1186 }
1187
pcm_mmap_commit(struct pcm * pcm,unsigned int offset,unsigned int frames)1188 int pcm_mmap_commit(struct pcm *pcm, unsigned int offset __attribute__((unused)), unsigned int frames)
1189 {
1190 /* update the application pointer in userspace and kernel */
1191 pcm_mmap_appl_forward(pcm, frames);
1192 pcm_sync_ptr(pcm, 0);
1193
1194 return frames;
1195 }
1196
pcm_avail_update(struct pcm * pcm)1197 int pcm_avail_update(struct pcm *pcm)
1198 {
1199 pcm_sync_ptr(pcm, 0);
1200 return pcm_mmap_avail(pcm);
1201 }
1202
pcm_state(struct pcm * pcm)1203 int pcm_state(struct pcm *pcm)
1204 {
1205 int err = pcm_sync_ptr(pcm, 0);
1206 if (err < 0)
1207 return err;
1208
1209 return pcm->mmap_status->state;
1210 }
1211
pcm_set_avail_min(struct pcm * pcm,int avail_min)1212 int pcm_set_avail_min(struct pcm *pcm, int avail_min)
1213 {
1214 if ((~pcm->flags) & (PCM_MMAP | PCM_NOIRQ))
1215 return -ENOSYS;
1216
1217 pcm->config.avail_min = avail_min;
1218 return 0;
1219 }
1220
pcm_wait(struct pcm * pcm,int timeout)1221 int pcm_wait(struct pcm *pcm, int timeout)
1222 {
1223 struct pollfd pfd;
1224 int err;
1225
1226 pfd.fd = pcm->fd;
1227 pfd.events = POLLOUT | POLLERR | POLLNVAL;
1228
1229 do {
1230 /* let's wait for avail or timeout */
1231 err = pcm->ops->poll(pcm->data, &pfd, 1, timeout);
1232 if (err < 0)
1233 return -errno;
1234
1235 /* timeout ? */
1236 if (err == 0)
1237 return 0;
1238
1239 /* have we been interrupted ? */
1240 if (errno == -EINTR)
1241 continue;
1242
1243 /* check for any errors */
1244 if (pfd.revents & (POLLERR | POLLNVAL)) {
1245 switch (pcm_state(pcm)) {
1246 case PCM_STATE_XRUN:
1247 return -EPIPE;
1248 case PCM_STATE_SUSPENDED:
1249 return -ESTRPIPE;
1250 case PCM_STATE_DISCONNECTED:
1251 return -ENODEV;
1252 default:
1253 return -EIO;
1254 }
1255 }
1256 /* poll again if fd not ready for IO */
1257 } while (!(pfd.revents & (POLLIN | POLLOUT)));
1258
1259 return 1;
1260 }
1261
pcm_get_poll_fd(struct pcm * pcm)1262 int pcm_get_poll_fd(struct pcm *pcm)
1263 {
1264 return pcm->fd;
1265 }
1266
pcm_mmap_transfer(struct pcm * pcm,const void * buffer,unsigned int bytes)1267 int pcm_mmap_transfer(struct pcm *pcm, const void *buffer, unsigned int bytes)
1268 {
1269 int err = 0, frames, avail;
1270 unsigned int offset = 0, count;
1271
1272 if (bytes == 0)
1273 return 0;
1274
1275 count = pcm_bytes_to_frames(pcm, bytes);
1276
1277 while (count > 0) {
1278
1279 /* get the available space for writing new frames */
1280 avail = pcm_avail_update(pcm);
1281 if (avail < 0) {
1282 fprintf(stderr, "cannot determine available mmap frames");
1283 return err;
1284 }
1285
1286 /* start the audio if we reach the threshold */
1287 if (!pcm->running &&
1288 (pcm->buffer_size - avail) >= pcm->config.start_threshold) {
1289 if (pcm_start(pcm) < 0) {
1290 fprintf(stderr, "start error: hw 0x%x app 0x%x avail 0x%x\n",
1291 (unsigned int)pcm->mmap_status->hw_ptr,
1292 (unsigned int)pcm->mmap_control->appl_ptr,
1293 avail);
1294 return -errno;
1295 }
1296 pcm->wait_for_avail_min = 0;
1297 }
1298
1299 /* sleep until we have space to write new frames */
1300 if (pcm->running) {
1301 /* enable waiting for avail_min threshold when less frames than we have to write
1302 * are available. */
1303 if (!pcm->wait_for_avail_min && (count > (unsigned int)avail))
1304 pcm->wait_for_avail_min = 1;
1305
1306 if (pcm->wait_for_avail_min && (avail < pcm->config.avail_min)) {
1307 int time = -1;
1308
1309 /* disable waiting for avail_min threshold to allow small amounts of data to be
1310 * written without waiting as long as there is enough room in buffer. */
1311 pcm->wait_for_avail_min = 0;
1312
1313 if (pcm->flags & PCM_NOIRQ)
1314 time = (pcm->config.avail_min - avail) / pcm->noirq_frames_per_msec;
1315
1316 err = pcm_wait(pcm, time);
1317 if (err < 0) {
1318 pcm->prepared = false;
1319 pcm->running = false;
1320 oops(pcm, errno, "wait error: hw 0x%x app 0x%x avail 0x%x\n",
1321 (unsigned int)pcm->mmap_status->hw_ptr,
1322 (unsigned int)pcm->mmap_control->appl_ptr,
1323 avail);
1324 pcm->mmap_control->appl_ptr = 0;
1325 return err;
1326 }
1327 continue;
1328 }
1329 }
1330
1331 frames = count;
1332 if (frames > avail)
1333 frames = avail;
1334
1335 if (!frames)
1336 break;
1337
1338 /* copy frames from buffer */
1339 frames = pcm_mmap_transfer_areas(pcm, (void *)buffer, offset, frames);
1340 if (frames < 0) {
1341 fprintf(stderr, "write error: hw 0x%x app 0x%x avail 0x%x\n",
1342 (unsigned int)pcm->mmap_status->hw_ptr,
1343 (unsigned int)pcm->mmap_control->appl_ptr,
1344 avail);
1345 return frames;
1346 }
1347
1348 offset += frames;
1349 count -= frames;
1350 }
1351
1352 return 0;
1353 }
1354
pcm_mmap_write(struct pcm * pcm,const void * data,unsigned int count)1355 int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count)
1356 {
1357 if ((~pcm->flags) & (PCM_OUT | PCM_MMAP))
1358 return -ENOSYS;
1359
1360 return pcm_mmap_transfer(pcm, (void *)data, count);
1361 }
1362
pcm_mmap_read(struct pcm * pcm,void * data,unsigned int count)1363 int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count)
1364 {
1365 if ((~pcm->flags) & (PCM_IN | PCM_MMAP))
1366 return -ENOSYS;
1367
1368 return pcm_mmap_transfer(pcm, data, count);
1369 }
1370
pcm_ioctl(struct pcm * pcm,int request,...)1371 int pcm_ioctl(struct pcm *pcm, int request, ...)
1372 {
1373 va_list ap;
1374 void * arg;
1375
1376 if (!pcm_is_ready(pcm))
1377 return -1;
1378
1379 va_start(ap, request);
1380 arg = va_arg(ap, void *);
1381 va_end(ap);
1382
1383 return pcm->ops->ioctl(pcm->data, request, arg);
1384 }
1385