xref: /openbmc/qemu/audio/ossaudio.c (revision 86044b24)
1 /*
2  * QEMU OSS audio driver
3  *
4  * Copyright (c) 2003-2005 Vassili Karpov (malc)
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include <sys/ioctl.h>
27 #include <sys/soundcard.h>
28 #include "qemu/main-loop.h"
29 #include "qemu/module.h"
30 #include "qemu/host-utils.h"
31 #include "audio.h"
32 #include "trace.h"
33 
34 #define AUDIO_CAP "oss"
35 #include "audio_int.h"
36 
37 #if defined OSS_GETVERSION && defined SNDCTL_DSP_POLICY
38 #define USE_DSP_POLICY
39 #endif
40 
41 typedef struct OSSVoiceOut {
42     HWVoiceOut hw;
43     int fd;
44     int nfrags;
45     int fragsize;
46     int mmapped;
47     Audiodev *dev;
48 } OSSVoiceOut;
49 
50 typedef struct OSSVoiceIn {
51     HWVoiceIn hw;
52     int fd;
53     int nfrags;
54     int fragsize;
55     Audiodev *dev;
56 } OSSVoiceIn;
57 
58 struct oss_params {
59     int freq;
60     int fmt;
61     int nchannels;
62     int nfrags;
63     int fragsize;
64 };
65 
66 static void GCC_FMT_ATTR (2, 3) oss_logerr (int err, const char *fmt, ...)
67 {
68     va_list ap;
69 
70     va_start (ap, fmt);
71     AUD_vlog (AUDIO_CAP, fmt, ap);
72     va_end (ap);
73 
74     AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
75 }
76 
77 static void GCC_FMT_ATTR (3, 4) oss_logerr2 (
78     int err,
79     const char *typ,
80     const char *fmt,
81     ...
82     )
83 {
84     va_list ap;
85 
86     AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
87 
88     va_start (ap, fmt);
89     AUD_vlog (AUDIO_CAP, fmt, ap);
90     va_end (ap);
91 
92     AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
93 }
94 
95 static void oss_anal_close (int *fdp)
96 {
97     int err;
98 
99     qemu_set_fd_handler (*fdp, NULL, NULL, NULL);
100     err = close (*fdp);
101     if (err) {
102         oss_logerr (errno, "Failed to close file(fd=%d)\n", *fdp);
103     }
104     *fdp = -1;
105 }
106 
107 static void oss_helper_poll_out (void *opaque)
108 {
109     AudioState *s = opaque;
110     audio_run(s, "oss_poll_out");
111 }
112 
113 static void oss_helper_poll_in (void *opaque)
114 {
115     AudioState *s = opaque;
116     audio_run(s, "oss_poll_in");
117 }
118 
119 static void oss_poll_out (HWVoiceOut *hw)
120 {
121     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
122 
123     qemu_set_fd_handler(oss->fd, NULL, oss_helper_poll_out, hw->s);
124 }
125 
126 static void oss_poll_in (HWVoiceIn *hw)
127 {
128     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
129 
130     qemu_set_fd_handler(oss->fd, oss_helper_poll_in, NULL, hw->s);
131 }
132 
133 static int aud_to_ossfmt (AudioFormat fmt, int endianness)
134 {
135     switch (fmt) {
136     case AUDIO_FORMAT_S8:
137         return AFMT_S8;
138 
139     case AUDIO_FORMAT_U8:
140         return AFMT_U8;
141 
142     case AUDIO_FORMAT_S16:
143         if (endianness) {
144             return AFMT_S16_BE;
145         }
146         else {
147             return AFMT_S16_LE;
148         }
149 
150     case AUDIO_FORMAT_U16:
151         if (endianness) {
152             return AFMT_U16_BE;
153         }
154         else {
155             return AFMT_U16_LE;
156         }
157 
158     default:
159         dolog ("Internal logic error: Bad audio format %d\n", fmt);
160 #ifdef DEBUG_AUDIO
161         abort ();
162 #endif
163         return AFMT_U8;
164     }
165 }
166 
167 static int oss_to_audfmt (int ossfmt, AudioFormat *fmt, int *endianness)
168 {
169     switch (ossfmt) {
170     case AFMT_S8:
171         *endianness = 0;
172         *fmt = AUDIO_FORMAT_S8;
173         break;
174 
175     case AFMT_U8:
176         *endianness = 0;
177         *fmt = AUDIO_FORMAT_U8;
178         break;
179 
180     case AFMT_S16_LE:
181         *endianness = 0;
182         *fmt = AUDIO_FORMAT_S16;
183         break;
184 
185     case AFMT_U16_LE:
186         *endianness = 0;
187         *fmt = AUDIO_FORMAT_U16;
188         break;
189 
190     case AFMT_S16_BE:
191         *endianness = 1;
192         *fmt = AUDIO_FORMAT_S16;
193         break;
194 
195     case AFMT_U16_BE:
196         *endianness = 1;
197         *fmt = AUDIO_FORMAT_U16;
198         break;
199 
200     default:
201         dolog ("Unrecognized audio format %d\n", ossfmt);
202         return -1;
203     }
204 
205     return 0;
206 }
207 
208 #if defined DEBUG_MISMATCHES || defined DEBUG
209 static void oss_dump_info (struct oss_params *req, struct oss_params *obt)
210 {
211     dolog ("parameter | requested value | obtained value\n");
212     dolog ("format    |      %10d |     %10d\n", req->fmt, obt->fmt);
213     dolog ("channels  |      %10d |     %10d\n",
214            req->nchannels, obt->nchannels);
215     dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
216     dolog ("nfrags    |      %10d |     %10d\n", req->nfrags, obt->nfrags);
217     dolog ("fragsize  |      %10d |     %10d\n",
218            req->fragsize, obt->fragsize);
219 }
220 #endif
221 
222 #ifdef USE_DSP_POLICY
223 static int oss_get_version (int fd, int *version, const char *typ)
224 {
225     if (ioctl (fd, OSS_GETVERSION, &version)) {
226 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
227         /*
228          * Looks like atm (20100109) FreeBSD knows OSS_GETVERSION
229          * since 7.x, but currently only on the mixer device (or in
230          * the Linuxolator), and in the native version that part of
231          * the code is in fact never reached so the ioctl fails anyway.
232          * Until this is fixed, just check the errno and if its what
233          * FreeBSD's sound drivers return atm assume they are new enough.
234          */
235         if (errno == EINVAL) {
236             *version = 0x040000;
237             return 0;
238         }
239 #endif
240         oss_logerr2 (errno, typ, "Failed to get OSS version\n");
241         return -1;
242     }
243     return 0;
244 }
245 #endif
246 
247 static int oss_open(int in, struct oss_params *req, audsettings *as,
248                     struct oss_params *obt, int *pfd, Audiodev *dev)
249 {
250     AudiodevOssOptions *oopts = &dev->u.oss;
251     AudiodevOssPerDirectionOptions *opdo = in ? oopts->in : oopts->out;
252     int fd;
253     int oflags = (oopts->has_exclusive && oopts->exclusive) ? O_EXCL : 0;
254     audio_buf_info abinfo;
255     int fmt, freq, nchannels;
256     int setfragment = 1;
257     const char *dspname = opdo->has_dev ? opdo->dev : "/dev/dsp";
258     const char *typ = in ? "ADC" : "DAC";
259 #ifdef USE_DSP_POLICY
260     int policy = oopts->has_dsp_policy ? oopts->dsp_policy : 5;
261 #endif
262 
263     /* Kludge needed to have working mmap on Linux */
264     oflags |= (oopts->has_try_mmap && oopts->try_mmap) ?
265         O_RDWR : (in ? O_RDONLY : O_WRONLY);
266 
267     fd = open (dspname, oflags | O_NONBLOCK);
268     if (-1 == fd) {
269         oss_logerr2 (errno, typ, "Failed to open `%s'\n", dspname);
270         return -1;
271     }
272 
273     freq = req->freq;
274     nchannels = req->nchannels;
275     fmt = req->fmt;
276     req->nfrags = opdo->has_buffer_count ? opdo->buffer_count : 4;
277     req->fragsize = audio_buffer_bytes(
278         qapi_AudiodevOssPerDirectionOptions_base(opdo), as, 23220);
279 
280     if (ioctl (fd, SNDCTL_DSP_SAMPLESIZE, &fmt)) {
281         oss_logerr2 (errno, typ, "Failed to set sample size %d\n", req->fmt);
282         goto err;
283     }
284 
285     if (ioctl (fd, SNDCTL_DSP_CHANNELS, &nchannels)) {
286         oss_logerr2 (errno, typ, "Failed to set number of channels %d\n",
287                      req->nchannels);
288         goto err;
289     }
290 
291     if (ioctl (fd, SNDCTL_DSP_SPEED, &freq)) {
292         oss_logerr2 (errno, typ, "Failed to set frequency %d\n", req->freq);
293         goto err;
294     }
295 
296     if (ioctl (fd, SNDCTL_DSP_NONBLOCK, NULL)) {
297         oss_logerr2 (errno, typ, "Failed to set non-blocking mode\n");
298         goto err;
299     }
300 
301 #ifdef USE_DSP_POLICY
302     if (policy >= 0) {
303         int version;
304 
305         if (!oss_get_version (fd, &version, typ)) {
306             trace_oss_version(version);
307 
308             if (version >= 0x040000) {
309                 int policy2 = policy;
310                 if (ioctl(fd, SNDCTL_DSP_POLICY, &policy2)) {
311                     oss_logerr2 (errno, typ,
312                                  "Failed to set timing policy to %d\n",
313                                  policy);
314                     goto err;
315                 }
316                 setfragment = 0;
317             }
318         }
319     }
320 #endif
321 
322     if (setfragment) {
323         int mmmmssss = (req->nfrags << 16) | ctz32 (req->fragsize);
324         if (ioctl (fd, SNDCTL_DSP_SETFRAGMENT, &mmmmssss)) {
325             oss_logerr2 (errno, typ, "Failed to set buffer length (%d, %d)\n",
326                          req->nfrags, req->fragsize);
327             goto err;
328         }
329     }
330 
331     if (ioctl (fd, in ? SNDCTL_DSP_GETISPACE : SNDCTL_DSP_GETOSPACE, &abinfo)) {
332         oss_logerr2 (errno, typ, "Failed to get buffer length\n");
333         goto err;
334     }
335 
336     if (!abinfo.fragstotal || !abinfo.fragsize) {
337         AUD_log (AUDIO_CAP, "Returned bogus buffer information(%d, %d) for %s\n",
338                  abinfo.fragstotal, abinfo.fragsize, typ);
339         goto err;
340     }
341 
342     obt->fmt = fmt;
343     obt->nchannels = nchannels;
344     obt->freq = freq;
345     obt->nfrags = abinfo.fragstotal;
346     obt->fragsize = abinfo.fragsize;
347     *pfd = fd;
348 
349 #ifdef DEBUG_MISMATCHES
350     if ((req->fmt != obt->fmt) ||
351         (req->nchannels != obt->nchannels) ||
352         (req->freq != obt->freq) ||
353         (req->fragsize != obt->fragsize) ||
354         (req->nfrags != obt->nfrags)) {
355         dolog ("Audio parameters mismatch\n");
356         oss_dump_info (req, obt);
357     }
358 #endif
359 
360 #ifdef DEBUG
361     oss_dump_info (req, obt);
362 #endif
363     return 0;
364 
365  err:
366     oss_anal_close (&fd);
367     return -1;
368 }
369 
370 static size_t oss_get_available_bytes(OSSVoiceOut *oss)
371 {
372     int err;
373     struct count_info cntinfo;
374     assert(oss->mmapped);
375 
376     err = ioctl(oss->fd, SNDCTL_DSP_GETOPTR, &cntinfo);
377     if (err < 0) {
378         oss_logerr(errno, "SNDCTL_DSP_GETOPTR failed\n");
379         return 0;
380     }
381 
382     return audio_ring_dist(cntinfo.ptr, oss->hw.pos_emul, oss->hw.size_emul);
383 }
384 
385 static void *oss_get_buffer_out(HWVoiceOut *hw, size_t *size)
386 {
387     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
388     if (oss->mmapped) {
389         *size = MIN(oss_get_available_bytes(oss), hw->size_emul - hw->pos_emul);
390         return hw->buf_emul + hw->pos_emul;
391     } else {
392         return audio_generic_get_buffer_out(hw, size);
393     }
394 }
395 
396 static size_t oss_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)
397 {
398     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
399     if (oss->mmapped) {
400         assert(buf == hw->buf_emul + hw->pos_emul && size < hw->size_emul);
401 
402         hw->pos_emul = (hw->pos_emul + size) % hw->size_emul;
403         return size;
404     } else {
405         return audio_generic_put_buffer_out(hw, buf, size);
406     }
407 }
408 
409 static size_t oss_write(HWVoiceOut *hw, void *buf, size_t len)
410 {
411     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
412     size_t pos;
413 
414     if (oss->mmapped) {
415         size_t total_len;
416         len = MIN(len, oss_get_available_bytes(oss));
417 
418         total_len = len;
419         while (len) {
420             size_t to_copy = MIN(len, hw->size_emul - hw->pos_emul);
421             memcpy(hw->buf_emul + hw->pos_emul, buf, to_copy);
422 
423             hw->pos_emul = (hw->pos_emul + to_copy) % hw->pos_emul;
424             buf += to_copy;
425             len -= to_copy;
426         }
427         return total_len;
428     }
429 
430     pos = 0;
431     while (len) {
432         ssize_t bytes_written;
433         void *pcm = advance(buf, pos);
434 
435         bytes_written = write(oss->fd, pcm, len);
436         if (bytes_written < 0) {
437             if (errno != EAGAIN) {
438                 oss_logerr(errno, "failed to write %zu bytes\n",
439                            len);
440             }
441             return pos;
442         }
443 
444         pos += bytes_written;
445         if (bytes_written < len) {
446             break;
447         }
448         len -= bytes_written;
449     }
450     return pos;
451 }
452 
453 static void oss_fini_out (HWVoiceOut *hw)
454 {
455     int err;
456     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
457 
458     ldebug ("oss_fini\n");
459     oss_anal_close (&oss->fd);
460 
461     if (oss->mmapped && hw->buf_emul) {
462         err = munmap(hw->buf_emul, hw->size_emul);
463         if (err) {
464             oss_logerr(errno, "Failed to unmap buffer %p, size %zu\n",
465                        hw->buf_emul, hw->size_emul);
466         }
467         hw->buf_emul = NULL;
468     }
469 }
470 
471 static int oss_init_out(HWVoiceOut *hw, struct audsettings *as,
472                         void *drv_opaque)
473 {
474     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
475     struct oss_params req, obt;
476     int endianness;
477     int err;
478     int fd;
479     AudioFormat effective_fmt;
480     struct audsettings obt_as;
481     Audiodev *dev = drv_opaque;
482     AudiodevOssOptions *oopts = &dev->u.oss;
483 
484     oss->fd = -1;
485 
486     req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
487     req.freq = as->freq;
488     req.nchannels = as->nchannels;
489 
490     if (oss_open(0, &req, as, &obt, &fd, dev)) {
491         return -1;
492     }
493 
494     err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
495     if (err) {
496         oss_anal_close (&fd);
497         return -1;
498     }
499 
500     obt_as.freq = obt.freq;
501     obt_as.nchannels = obt.nchannels;
502     obt_as.fmt = effective_fmt;
503     obt_as.endianness = endianness;
504 
505     audio_pcm_init_info (&hw->info, &obt_as);
506     oss->nfrags = obt.nfrags;
507     oss->fragsize = obt.fragsize;
508 
509     if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
510         dolog ("warning: Misaligned DAC buffer, size %d, alignment %d\n",
511                obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
512     }
513 
514     hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
515 
516     oss->mmapped = 0;
517     if (oopts->has_try_mmap && oopts->try_mmap) {
518         hw->size_emul = hw->samples * hw->info.bytes_per_frame;
519         hw->buf_emul = mmap(
520             NULL,
521             hw->size_emul,
522             PROT_READ | PROT_WRITE,
523             MAP_SHARED,
524             fd,
525             0
526             );
527         if (hw->buf_emul == MAP_FAILED) {
528             oss_logerr(errno, "Failed to map %zu bytes of DAC\n",
529                        hw->size_emul);
530             hw->buf_emul = NULL;
531         } else {
532             int err;
533             int trig = 0;
534             if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
535                 oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
536             }
537             else {
538                 trig = PCM_ENABLE_OUTPUT;
539                 if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
540                     oss_logerr (
541                         errno,
542                         "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n"
543                         );
544                 }
545                 else {
546                     oss->mmapped = 1;
547                 }
548             }
549 
550             if (!oss->mmapped) {
551                 err = munmap(hw->buf_emul, hw->size_emul);
552                 if (err) {
553                     oss_logerr(errno, "Failed to unmap buffer %p size %zu\n",
554                                hw->buf_emul, hw->size_emul);
555                 }
556                 hw->buf_emul = NULL;
557             }
558         }
559     }
560 
561     oss->fd = fd;
562     oss->dev = dev;
563     return 0;
564 }
565 
566 static void oss_enable_out(HWVoiceOut *hw, bool enable)
567 {
568     int trig;
569     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
570     AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
571 
572     if (enable) {
573         bool poll_mode = opdo->try_poll;
574 
575         ldebug("enabling voice\n");
576         if (poll_mode) {
577             oss_poll_out(hw);
578             poll_mode = 0;
579         }
580         hw->poll_mode = poll_mode;
581 
582         if (!oss->mmapped) {
583             return;
584         }
585 
586         audio_pcm_info_clear_buf(&hw->info, hw->buf_emul, hw->mix_buf->size);
587         trig = PCM_ENABLE_OUTPUT;
588         if (ioctl(oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
589             oss_logerr(errno,
590                        "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n");
591             return;
592         }
593     } else {
594         if (hw->poll_mode) {
595             qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
596             hw->poll_mode = 0;
597         }
598 
599         if (!oss->mmapped) {
600             return;
601         }
602 
603         ldebug ("disabling voice\n");
604         trig = 0;
605         if (ioctl (oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
606             oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
607             return;
608         }
609     }
610 }
611 
612 static int oss_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
613 {
614     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
615     struct oss_params req, obt;
616     int endianness;
617     int err;
618     int fd;
619     AudioFormat effective_fmt;
620     struct audsettings obt_as;
621     Audiodev *dev = drv_opaque;
622 
623     oss->fd = -1;
624 
625     req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
626     req.freq = as->freq;
627     req.nchannels = as->nchannels;
628     if (oss_open(1, &req, as, &obt, &fd, dev)) {
629         return -1;
630     }
631 
632     err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
633     if (err) {
634         oss_anal_close (&fd);
635         return -1;
636     }
637 
638     obt_as.freq = obt.freq;
639     obt_as.nchannels = obt.nchannels;
640     obt_as.fmt = effective_fmt;
641     obt_as.endianness = endianness;
642 
643     audio_pcm_init_info (&hw->info, &obt_as);
644     oss->nfrags = obt.nfrags;
645     oss->fragsize = obt.fragsize;
646 
647     if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
648         dolog ("warning: Misaligned ADC buffer, size %d, alignment %d\n",
649                obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
650     }
651 
652     hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
653 
654     oss->fd = fd;
655     oss->dev = dev;
656     return 0;
657 }
658 
659 static void oss_fini_in (HWVoiceIn *hw)
660 {
661     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
662 
663     oss_anal_close (&oss->fd);
664 }
665 
666 static size_t oss_read(HWVoiceIn *hw, void *buf, size_t len)
667 {
668     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
669     size_t pos = 0;
670 
671     while (len) {
672         ssize_t nread;
673 
674         void *dst = advance(buf, pos);
675         nread = read(oss->fd, dst, len);
676 
677         if (nread == -1) {
678             switch (errno) {
679             case EINTR:
680             case EAGAIN:
681                 break;
682             default:
683                 oss_logerr(errno, "Failed to read %zu bytes of audio (to %p)\n",
684                            len, dst);
685                 break;
686             }
687         }
688 
689         pos += nread;
690         len -= nread;
691     }
692 
693     return pos;
694 }
695 
696 static void oss_enable_in(HWVoiceIn *hw, bool enable)
697 {
698     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
699     AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
700 
701     if (enable) {
702         bool poll_mode = opdo->try_poll;
703 
704         if (poll_mode) {
705             oss_poll_in(hw);
706             poll_mode = 0;
707         }
708         hw->poll_mode = poll_mode;
709     } else {
710         if (hw->poll_mode) {
711             hw->poll_mode = 0;
712             qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
713         }
714     }
715 }
716 
717 static void oss_init_per_direction(AudiodevOssPerDirectionOptions *opdo)
718 {
719     if (!opdo->has_try_poll) {
720         opdo->try_poll = true;
721         opdo->has_try_poll = true;
722     }
723 }
724 
725 static void *oss_audio_init(Audiodev *dev)
726 {
727     AudiodevOssOptions *oopts;
728     assert(dev->driver == AUDIODEV_DRIVER_OSS);
729 
730     oopts = &dev->u.oss;
731     oss_init_per_direction(oopts->in);
732     oss_init_per_direction(oopts->out);
733 
734     if (access(oopts->in->has_dev ? oopts->in->dev : "/dev/dsp",
735                R_OK | W_OK) < 0 ||
736         access(oopts->out->has_dev ? oopts->out->dev : "/dev/dsp",
737                R_OK | W_OK) < 0) {
738         return NULL;
739     }
740     return dev;
741 }
742 
743 static void oss_audio_fini (void *opaque)
744 {
745 }
746 
747 static struct audio_pcm_ops oss_pcm_ops = {
748     .init_out = oss_init_out,
749     .fini_out = oss_fini_out,
750     .write    = oss_write,
751     .get_buffer_out = oss_get_buffer_out,
752     .put_buffer_out = oss_put_buffer_out,
753     .enable_out = oss_enable_out,
754 
755     .init_in  = oss_init_in,
756     .fini_in  = oss_fini_in,
757     .read     = oss_read,
758     .enable_in = oss_enable_in
759 };
760 
761 static struct audio_driver oss_audio_driver = {
762     .name           = "oss",
763     .descr          = "OSS http://www.opensound.com",
764     .init           = oss_audio_init,
765     .fini           = oss_audio_fini,
766     .pcm_ops        = &oss_pcm_ops,
767     .can_be_default = 1,
768     .max_voices_out = INT_MAX,
769     .max_voices_in  = INT_MAX,
770     .voice_size_out = sizeof (OSSVoiceOut),
771     .voice_size_in  = sizeof (OSSVoiceIn)
772 };
773 
774 static void register_audio_oss(void)
775 {
776     audio_driver_register(&oss_audio_driver);
777 }
778 type_init(register_audio_oss);
779