xref: /openbmc/qemu/audio/ossaudio.c (revision 69a80279)
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 "qapi/error.h"
32 #include "audio.h"
33 #include "trace.h"
34 
35 #define AUDIO_CAP "oss"
36 #include "audio_int.h"
37 
38 #if defined OSS_GETVERSION && defined SNDCTL_DSP_POLICY
39 #define USE_DSP_POLICY
40 #endif
41 
42 typedef struct OSSVoiceOut {
43     HWVoiceOut hw;
44     int fd;
45     int nfrags;
46     int fragsize;
47     int mmapped;
48     Audiodev *dev;
49 } OSSVoiceOut;
50 
51 typedef struct OSSVoiceIn {
52     HWVoiceIn hw;
53     int fd;
54     int nfrags;
55     int fragsize;
56     Audiodev *dev;
57 } OSSVoiceIn;
58 
59 struct oss_params {
60     int freq;
61     int fmt;
62     int nchannels;
63     int nfrags;
64     int fragsize;
65 };
66 
67 static void G_GNUC_PRINTF (2, 3) oss_logerr (int err, const char *fmt, ...)
68 {
69     va_list ap;
70 
71     va_start (ap, fmt);
72     AUD_vlog (AUDIO_CAP, fmt, ap);
73     va_end (ap);
74 
75     AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
76 }
77 
78 static void G_GNUC_PRINTF (3, 4) oss_logerr2 (
79     int err,
80     const char *typ,
81     const char *fmt,
82     ...
83     )
84 {
85     va_list ap;
86 
87     AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
88 
89     va_start (ap, fmt);
90     AUD_vlog (AUDIO_CAP, fmt, ap);
91     va_end (ap);
92 
93     AUD_log (AUDIO_CAP, "Reason: %s\n", strerror (err));
94 }
95 
96 static void oss_anal_close (int *fdp)
97 {
98     int err;
99 
100     qemu_set_fd_handler (*fdp, NULL, NULL, NULL);
101     err = close (*fdp);
102     if (err) {
103         oss_logerr (errno, "Failed to close file(fd=%d)\n", *fdp);
104     }
105     *fdp = -1;
106 }
107 
108 static void oss_helper_poll_out (void *opaque)
109 {
110     AudioState *s = opaque;
111     audio_run(s, "oss_poll_out");
112 }
113 
114 static void oss_helper_poll_in (void *opaque)
115 {
116     AudioState *s = opaque;
117     audio_run(s, "oss_poll_in");
118 }
119 
120 static void oss_poll_out (HWVoiceOut *hw)
121 {
122     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
123 
124     qemu_set_fd_handler(oss->fd, NULL, oss_helper_poll_out, hw->s);
125 }
126 
127 static void oss_poll_in (HWVoiceIn *hw)
128 {
129     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
130 
131     qemu_set_fd_handler(oss->fd, oss_helper_poll_in, NULL, hw->s);
132 }
133 
134 static int aud_to_ossfmt (AudioFormat fmt, int endianness)
135 {
136     switch (fmt) {
137     case AUDIO_FORMAT_S8:
138         return AFMT_S8;
139 
140     case AUDIO_FORMAT_U8:
141         return AFMT_U8;
142 
143     case AUDIO_FORMAT_S16:
144         if (endianness) {
145             return AFMT_S16_BE;
146         } else {
147             return AFMT_S16_LE;
148         }
149 
150     case AUDIO_FORMAT_U16:
151         if (endianness) {
152             return AFMT_U16_BE;
153         } else {
154             return AFMT_U16_LE;
155         }
156 
157     default:
158         dolog ("Internal logic error: Bad audio format %d\n", fmt);
159 #ifdef DEBUG_AUDIO
160         abort ();
161 #endif
162         return AFMT_U8;
163     }
164 }
165 
166 static int oss_to_audfmt (int ossfmt, AudioFormat *fmt, int *endianness)
167 {
168     switch (ossfmt) {
169     case AFMT_S8:
170         *endianness = 0;
171         *fmt = AUDIO_FORMAT_S8;
172         break;
173 
174     case AFMT_U8:
175         *endianness = 0;
176         *fmt = AUDIO_FORMAT_U8;
177         break;
178 
179     case AFMT_S16_LE:
180         *endianness = 0;
181         *fmt = AUDIO_FORMAT_S16;
182         break;
183 
184     case AFMT_U16_LE:
185         *endianness = 0;
186         *fmt = AUDIO_FORMAT_U16;
187         break;
188 
189     case AFMT_S16_BE:
190         *endianness = 1;
191         *fmt = AUDIO_FORMAT_S16;
192         break;
193 
194     case AFMT_U16_BE:
195         *endianness = 1;
196         *fmt = AUDIO_FORMAT_U16;
197         break;
198 
199     default:
200         dolog ("Unrecognized audio format %d\n", ossfmt);
201         return -1;
202     }
203 
204     return 0;
205 }
206 
207 #if defined DEBUG_MISMATCHES || defined DEBUG
208 static void oss_dump_info (struct oss_params *req, struct oss_params *obt)
209 {
210     dolog ("parameter | requested value | obtained value\n");
211     dolog ("format    |      %10d |     %10d\n", req->fmt, obt->fmt);
212     dolog ("channels  |      %10d |     %10d\n",
213            req->nchannels, obt->nchannels);
214     dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
215     dolog ("nfrags    |      %10d |     %10d\n", req->nfrags, obt->nfrags);
216     dolog ("fragsize  |      %10d |     %10d\n",
217            req->fragsize, obt->fragsize);
218 }
219 #endif
220 
221 #ifdef USE_DSP_POLICY
222 static int oss_get_version (int fd, int *version, const char *typ)
223 {
224     if (ioctl (fd, OSS_GETVERSION, &version)) {
225 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
226         /*
227          * Looks like atm (20100109) FreeBSD knows OSS_GETVERSION
228          * since 7.x, but currently only on the mixer device (or in
229          * the Linuxolator), and in the native version that part of
230          * the code is in fact never reached so the ioctl fails anyway.
231          * Until this is fixed, just check the errno and if its what
232          * FreeBSD's sound drivers return atm assume they are new enough.
233          */
234         if (errno == EINVAL) {
235             *version = 0x040000;
236             return 0;
237         }
238 #endif
239         oss_logerr2 (errno, typ, "Failed to get OSS version\n");
240         return -1;
241     }
242     return 0;
243 }
244 #endif
245 
246 static int oss_open(int in, struct oss_params *req, audsettings *as,
247                     struct oss_params *obt, int *pfd, Audiodev *dev)
248 {
249     AudiodevOssOptions *oopts = &dev->u.oss;
250     AudiodevOssPerDirectionOptions *opdo = in ? oopts->in : oopts->out;
251     int fd;
252     int oflags = (oopts->has_exclusive && oopts->exclusive) ? O_EXCL : 0;
253     audio_buf_info abinfo;
254     int fmt, freq, nchannels;
255     int setfragment = 1;
256     const char *dspname = opdo->dev ?: "/dev/dsp";
257     const char *typ = in ? "ADC" : "DAC";
258 #ifdef USE_DSP_POLICY
259     int policy = oopts->has_dsp_policy ? oopts->dsp_policy : 5;
260 #endif
261 
262     /* Kludge needed to have working mmap on Linux */
263     oflags |= (oopts->has_try_mmap && oopts->try_mmap) ?
264         O_RDWR : (in ? O_RDONLY : O_WRONLY);
265 
266     fd = open (dspname, oflags | O_NONBLOCK);
267     if (-1 == fd) {
268         oss_logerr2 (errno, typ, "Failed to open `%s'\n", dspname);
269         return -1;
270     }
271 
272     freq = req->freq;
273     nchannels = req->nchannels;
274     fmt = req->fmt;
275     req->nfrags = opdo->has_buffer_count ? opdo->buffer_count : 4;
276     req->fragsize = audio_buffer_bytes(
277         qapi_AudiodevOssPerDirectionOptions_base(opdo), as, 23220);
278 
279     if (ioctl (fd, SNDCTL_DSP_SAMPLESIZE, &fmt)) {
280         oss_logerr2 (errno, typ, "Failed to set sample size %d\n", req->fmt);
281         goto err;
282     }
283 
284     if (ioctl (fd, SNDCTL_DSP_CHANNELS, &nchannels)) {
285         oss_logerr2 (errno, typ, "Failed to set number of channels %d\n",
286                      req->nchannels);
287         goto err;
288     }
289 
290     if (ioctl (fd, SNDCTL_DSP_SPEED, &freq)) {
291         oss_logerr2 (errno, typ, "Failed to set frequency %d\n", req->freq);
292         goto err;
293     }
294 
295     if (ioctl (fd, SNDCTL_DSP_NONBLOCK, NULL)) {
296         oss_logerr2 (errno, typ, "Failed to set non-blocking mode\n");
297         goto err;
298     }
299 
300 #ifdef USE_DSP_POLICY
301     if (policy >= 0) {
302         int version;
303 
304         if (!oss_get_version (fd, &version, typ)) {
305             trace_oss_version(version);
306 
307             if (version >= 0x040000) {
308                 int policy2 = policy;
309                 if (ioctl(fd, SNDCTL_DSP_POLICY, &policy2)) {
310                     oss_logerr2 (errno, typ,
311                                  "Failed to set timing policy to %d\n",
312                                  policy);
313                     goto err;
314                 }
315                 setfragment = 0;
316             }
317         }
318     }
319 #endif
320 
321     if (setfragment) {
322         int mmmmssss = (req->nfrags << 16) | ctz32 (req->fragsize);
323         if (ioctl (fd, SNDCTL_DSP_SETFRAGMENT, &mmmmssss)) {
324             oss_logerr2 (errno, typ, "Failed to set buffer length (%d, %d)\n",
325                          req->nfrags, req->fragsize);
326             goto err;
327         }
328     }
329 
330     if (ioctl (fd, in ? SNDCTL_DSP_GETISPACE : SNDCTL_DSP_GETOSPACE, &abinfo)) {
331         oss_logerr2 (errno, typ, "Failed to get buffer length\n");
332         goto err;
333     }
334 
335     if (!abinfo.fragstotal || !abinfo.fragsize) {
336         AUD_log (AUDIO_CAP, "Returned bogus buffer information(%d, %d) for %s\n",
337                  abinfo.fragstotal, abinfo.fragsize, typ);
338         goto err;
339     }
340 
341     obt->fmt = fmt;
342     obt->nchannels = nchannels;
343     obt->freq = freq;
344     obt->nfrags = abinfo.fragstotal;
345     obt->fragsize = abinfo.fragsize;
346     *pfd = fd;
347 
348 #ifdef DEBUG_MISMATCHES
349     if ((req->fmt != obt->fmt) ||
350         (req->nchannels != obt->nchannels) ||
351         (req->freq != obt->freq) ||
352         (req->fragsize != obt->fragsize) ||
353         (req->nfrags != obt->nfrags)) {
354         dolog ("Audio parameters mismatch\n");
355         oss_dump_info (req, obt);
356     }
357 #endif
358 
359 #ifdef DEBUG
360     oss_dump_info (req, obt);
361 #endif
362     return 0;
363 
364  err:
365     oss_anal_close (&fd);
366     return -1;
367 }
368 
369 static size_t oss_get_available_bytes(OSSVoiceOut *oss)
370 {
371     int err;
372     struct count_info cntinfo;
373     assert(oss->mmapped);
374 
375     err = ioctl(oss->fd, SNDCTL_DSP_GETOPTR, &cntinfo);
376     if (err < 0) {
377         oss_logerr(errno, "SNDCTL_DSP_GETOPTR failed\n");
378         return 0;
379     }
380 
381     return audio_ring_dist(cntinfo.ptr, oss->hw.pos_emul, oss->hw.size_emul);
382 }
383 
384 static void oss_run_buffer_out(HWVoiceOut *hw)
385 {
386     OSSVoiceOut *oss = (OSSVoiceOut *)hw;
387 
388     if (!oss->mmapped) {
389         audio_generic_run_buffer_out(hw);
390     }
391 }
392 
393 static size_t oss_buffer_get_free(HWVoiceOut *hw)
394 {
395     OSSVoiceOut *oss = (OSSVoiceOut *)hw;
396 
397     if (oss->mmapped) {
398         return oss_get_available_bytes(oss);
399     } else {
400         return audio_generic_buffer_get_free(hw);
401     }
402 }
403 
404 static void *oss_get_buffer_out(HWVoiceOut *hw, size_t *size)
405 {
406     OSSVoiceOut *oss = (OSSVoiceOut *)hw;
407 
408     if (oss->mmapped) {
409         *size = hw->size_emul - hw->pos_emul;
410         return hw->buf_emul + hw->pos_emul;
411     } else {
412         return audio_generic_get_buffer_out(hw, size);
413     }
414 }
415 
416 static size_t oss_put_buffer_out(HWVoiceOut *hw, void *buf, size_t size)
417 {
418     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
419     if (oss->mmapped) {
420         assert(buf == hw->buf_emul + hw->pos_emul && size < hw->size_emul);
421 
422         hw->pos_emul = (hw->pos_emul + size) % hw->size_emul;
423         return size;
424     } else {
425         return audio_generic_put_buffer_out(hw, buf, size);
426     }
427 }
428 
429 static size_t oss_write(HWVoiceOut *hw, void *buf, size_t len)
430 {
431     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
432     size_t pos;
433 
434     if (oss->mmapped) {
435         size_t total_len;
436         len = MIN(len, oss_get_available_bytes(oss));
437 
438         total_len = len;
439         while (len) {
440             size_t to_copy = MIN(len, hw->size_emul - hw->pos_emul);
441             memcpy(hw->buf_emul + hw->pos_emul, buf, to_copy);
442 
443             hw->pos_emul = (hw->pos_emul + to_copy) % hw->size_emul;
444             buf += to_copy;
445             len -= to_copy;
446         }
447         return total_len;
448     }
449 
450     pos = 0;
451     while (len) {
452         ssize_t bytes_written;
453         void *pcm = advance(buf, pos);
454 
455         bytes_written = write(oss->fd, pcm, len);
456         if (bytes_written < 0) {
457             if (errno != EAGAIN) {
458                 oss_logerr(errno, "failed to write %zu bytes\n",
459                            len);
460             }
461             return pos;
462         }
463 
464         pos += bytes_written;
465         if (bytes_written < len) {
466             break;
467         }
468         len -= bytes_written;
469     }
470     return pos;
471 }
472 
473 static void oss_fini_out (HWVoiceOut *hw)
474 {
475     int err;
476     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
477 
478     ldebug ("oss_fini\n");
479     oss_anal_close (&oss->fd);
480 
481     if (oss->mmapped && hw->buf_emul) {
482         err = munmap(hw->buf_emul, hw->size_emul);
483         if (err) {
484             oss_logerr(errno, "Failed to unmap buffer %p, size %zu\n",
485                        hw->buf_emul, hw->size_emul);
486         }
487         hw->buf_emul = NULL;
488     }
489 }
490 
491 static int oss_init_out(HWVoiceOut *hw, struct audsettings *as,
492                         void *drv_opaque)
493 {
494     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
495     struct oss_params req, obt;
496     int endianness;
497     int err;
498     int fd;
499     AudioFormat effective_fmt;
500     struct audsettings obt_as;
501     Audiodev *dev = drv_opaque;
502     AudiodevOssOptions *oopts = &dev->u.oss;
503 
504     oss->fd = -1;
505 
506     req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
507     req.freq = as->freq;
508     req.nchannels = as->nchannels;
509 
510     if (oss_open(0, &req, as, &obt, &fd, dev)) {
511         return -1;
512     }
513 
514     err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
515     if (err) {
516         oss_anal_close (&fd);
517         return -1;
518     }
519 
520     obt_as.freq = obt.freq;
521     obt_as.nchannels = obt.nchannels;
522     obt_as.fmt = effective_fmt;
523     obt_as.endianness = endianness;
524 
525     audio_pcm_init_info (&hw->info, &obt_as);
526     oss->nfrags = obt.nfrags;
527     oss->fragsize = obt.fragsize;
528 
529     if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
530         dolog ("warning: Misaligned DAC buffer, size %d, alignment %d\n",
531                obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
532     }
533 
534     hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
535 
536     oss->mmapped = 0;
537     if (oopts->has_try_mmap && oopts->try_mmap) {
538         hw->size_emul = hw->samples * hw->info.bytes_per_frame;
539         hw->buf_emul = mmap(
540             NULL,
541             hw->size_emul,
542             PROT_READ | PROT_WRITE,
543             MAP_SHARED,
544             fd,
545             0
546             );
547         if (hw->buf_emul == MAP_FAILED) {
548             oss_logerr(errno, "Failed to map %zu bytes of DAC\n",
549                        hw->size_emul);
550             hw->buf_emul = NULL;
551         } else {
552             int err;
553             int trig = 0;
554             if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
555                 oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
556             } else {
557                 trig = PCM_ENABLE_OUTPUT;
558                 if (ioctl (fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
559                     oss_logerr (
560                         errno,
561                         "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n"
562                         );
563                 } else {
564                     oss->mmapped = 1;
565                 }
566             }
567 
568             if (!oss->mmapped) {
569                 err = munmap(hw->buf_emul, hw->size_emul);
570                 if (err) {
571                     oss_logerr(errno, "Failed to unmap buffer %p size %zu\n",
572                                hw->buf_emul, hw->size_emul);
573                 }
574                 hw->buf_emul = NULL;
575             }
576         }
577     }
578 
579     oss->fd = fd;
580     oss->dev = dev;
581     return 0;
582 }
583 
584 static void oss_enable_out(HWVoiceOut *hw, bool enable)
585 {
586     int trig;
587     OSSVoiceOut *oss = (OSSVoiceOut *) hw;
588     AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
589 
590     if (enable) {
591         hw->poll_mode = opdo->try_poll;
592 
593         ldebug("enabling voice\n");
594         if (hw->poll_mode) {
595             oss_poll_out(hw);
596         }
597 
598         if (!oss->mmapped) {
599             return;
600         }
601 
602         audio_pcm_info_clear_buf(&hw->info, hw->buf_emul, hw->samples);
603         trig = PCM_ENABLE_OUTPUT;
604         if (ioctl(oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
605             oss_logerr(errno,
606                        "SNDCTL_DSP_SETTRIGGER PCM_ENABLE_OUTPUT failed\n");
607             return;
608         }
609     } else {
610         if (hw->poll_mode) {
611             qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
612             hw->poll_mode = 0;
613         }
614 
615         if (!oss->mmapped) {
616             return;
617         }
618 
619         ldebug ("disabling voice\n");
620         trig = 0;
621         if (ioctl (oss->fd, SNDCTL_DSP_SETTRIGGER, &trig) < 0) {
622             oss_logerr (errno, "SNDCTL_DSP_SETTRIGGER 0 failed\n");
623             return;
624         }
625     }
626 }
627 
628 static int oss_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
629 {
630     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
631     struct oss_params req, obt;
632     int endianness;
633     int err;
634     int fd;
635     AudioFormat effective_fmt;
636     struct audsettings obt_as;
637     Audiodev *dev = drv_opaque;
638 
639     oss->fd = -1;
640 
641     req.fmt = aud_to_ossfmt (as->fmt, as->endianness);
642     req.freq = as->freq;
643     req.nchannels = as->nchannels;
644     if (oss_open(1, &req, as, &obt, &fd, dev)) {
645         return -1;
646     }
647 
648     err = oss_to_audfmt (obt.fmt, &effective_fmt, &endianness);
649     if (err) {
650         oss_anal_close (&fd);
651         return -1;
652     }
653 
654     obt_as.freq = obt.freq;
655     obt_as.nchannels = obt.nchannels;
656     obt_as.fmt = effective_fmt;
657     obt_as.endianness = endianness;
658 
659     audio_pcm_init_info (&hw->info, &obt_as);
660     oss->nfrags = obt.nfrags;
661     oss->fragsize = obt.fragsize;
662 
663     if (obt.nfrags * obt.fragsize % hw->info.bytes_per_frame) {
664         dolog ("warning: Misaligned ADC buffer, size %d, alignment %d\n",
665                obt.nfrags * obt.fragsize, hw->info.bytes_per_frame);
666     }
667 
668     hw->samples = (obt.nfrags * obt.fragsize) / hw->info.bytes_per_frame;
669 
670     oss->fd = fd;
671     oss->dev = dev;
672     return 0;
673 }
674 
675 static void oss_fini_in (HWVoiceIn *hw)
676 {
677     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
678 
679     oss_anal_close (&oss->fd);
680 }
681 
682 static size_t oss_read(HWVoiceIn *hw, void *buf, size_t len)
683 {
684     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
685     size_t pos = 0;
686 
687     while (len) {
688         ssize_t nread;
689 
690         void *dst = advance(buf, pos);
691         nread = read(oss->fd, dst, len);
692 
693         if (nread == -1) {
694             switch (errno) {
695             case EINTR:
696             case EAGAIN:
697                 break;
698             default:
699                 oss_logerr(errno, "Failed to read %zu bytes of audio (to %p)\n",
700                            len, dst);
701                 break;
702             }
703             break;
704         }
705 
706         pos += nread;
707         len -= nread;
708     }
709 
710     return pos;
711 }
712 
713 static void oss_enable_in(HWVoiceIn *hw, bool enable)
714 {
715     OSSVoiceIn *oss = (OSSVoiceIn *) hw;
716     AudiodevOssPerDirectionOptions *opdo = oss->dev->u.oss.out;
717 
718     if (enable) {
719         hw->poll_mode = opdo->try_poll;
720 
721         if (hw->poll_mode) {
722             oss_poll_in(hw);
723         }
724     } else {
725         if (hw->poll_mode) {
726             qemu_set_fd_handler (oss->fd, NULL, NULL, NULL);
727             hw->poll_mode = 0;
728         }
729     }
730 }
731 
732 static void oss_init_per_direction(AudiodevOssPerDirectionOptions *opdo)
733 {
734     if (!opdo->has_try_poll) {
735         opdo->try_poll = true;
736         opdo->has_try_poll = true;
737     }
738 }
739 
740 static void *oss_audio_init(Audiodev *dev, Error **errp)
741 {
742     AudiodevOssOptions *oopts;
743     assert(dev->driver == AUDIODEV_DRIVER_OSS);
744 
745     oopts = &dev->u.oss;
746     oss_init_per_direction(oopts->in);
747     oss_init_per_direction(oopts->out);
748 
749     if (access(oopts->in->dev ?: "/dev/dsp", R_OK | W_OK) < 0) {
750         error_setg_errno(errp, errno, "%s not accessible", oopts->in->dev ?: "/dev/dsp");
751         return NULL;
752     }
753     if (access(oopts->out->dev ?: "/dev/dsp", R_OK | W_OK) < 0) {
754         error_setg_errno(errp, errno, "%s not accessible", oopts->out->dev ?: "/dev/dsp");
755         return NULL;
756     }
757     return dev;
758 }
759 
760 static void oss_audio_fini (void *opaque)
761 {
762 }
763 
764 static struct audio_pcm_ops oss_pcm_ops = {
765     .init_out = oss_init_out,
766     .fini_out = oss_fini_out,
767     .write    = oss_write,
768     .buffer_get_free = oss_buffer_get_free,
769     .run_buffer_out = oss_run_buffer_out,
770     .get_buffer_out = oss_get_buffer_out,
771     .put_buffer_out = oss_put_buffer_out,
772     .enable_out = oss_enable_out,
773 
774     .init_in  = oss_init_in,
775     .fini_in  = oss_fini_in,
776     .read     = oss_read,
777     .run_buffer_in = audio_generic_run_buffer_in,
778     .enable_in = oss_enable_in
779 };
780 
781 static struct audio_driver oss_audio_driver = {
782     .name           = "oss",
783     .descr          = "OSS http://www.opensound.com",
784     .init           = oss_audio_init,
785     .fini           = oss_audio_fini,
786     .pcm_ops        = &oss_pcm_ops,
787     .max_voices_out = INT_MAX,
788     .max_voices_in  = INT_MAX,
789     .voice_size_out = sizeof (OSSVoiceOut),
790     .voice_size_in  = sizeof (OSSVoiceIn)
791 };
792 
793 static void register_audio_oss(void)
794 {
795     audio_driver_register(&oss_audio_driver);
796 }
797 type_init(register_audio_oss);
798