diff options
author | Robin Gareus <robin@gareus.org> | 2019-07-24 16:29:59 +0200 |
---|---|---|
committer | Robin Gareus <robin@gareus.org> | 2019-07-24 16:40:32 +0200 |
commit | 0fe3cba8b131ca1196ef30c0ccb5acb914817276 (patch) | |
tree | 5b826a8f881addf6a334306b955b315bd602100c | |
parent | 31ec8ce7d18e36d3c765beeb0445eb946373addf (diff) |
Fix ALSA available buffersize detection:
buffer-size = periods * period-size
Previously, buffersize was used for period-size.
This fixes an issue with a dedicated .asoundrc configuring a specific
period-size or buffer-size that has to be exact.
Ardour's device configuration failed in this case.
This has not been an issues since most hardware devices offer a wide
range: 8 < period-size < 262144 ; 16 < buffer-size < 524288.
Only a subset of which (32 .8192) is allowed by Ardour.
-rw-r--r-- | libs/ardouralsautil/deviceparams.cc | 58 |
1 files changed, 56 insertions, 2 deletions
diff --git a/libs/ardouralsautil/deviceparams.cc b/libs/ardouralsautil/deviceparams.cc index 2e9f121a15..381f5b8f75 100644 --- a/libs/ardouralsautil/deviceparams.cc +++ b/libs/ardouralsautil/deviceparams.cc @@ -33,6 +33,10 @@ ARDOUR::get_alsa_device_parameters (const char* device_name, const bool play, AL nfo->valid = false; + unsigned long min_psiz, max_psiz; + unsigned long min_bufz, max_bufz; + unsigned int min_nper, max_nper; + err = snd_pcm_open (&pcm, device_name, play ? SND_PCM_STREAM_PLAYBACK : SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK); @@ -66,17 +70,67 @@ ARDOUR::get_alsa_device_parameters (const char* device_name, const bool play, AL goto error_out; } - err = snd_pcm_hw_params_get_buffer_size_min (hw_params, &nfo->min_size); + err = snd_pcm_hw_params_get_period_size_min (hw_params, &min_psiz, 0); + if (err < 0) { + errmsg = "Cannot get minimum period size"; + goto error_out; + } + err = snd_pcm_hw_params_get_period_size_max (hw_params, &max_psiz, 0); + if (err < 0) { + errmsg = "Cannot get maximum period size"; + goto error_out; + } + + err = snd_pcm_hw_params_get_buffer_size_min (hw_params, &min_bufz); if (err < 0) { errmsg = "Cannot get minimum buffer size"; goto error_out; } - err = snd_pcm_hw_params_get_buffer_size_max (hw_params, &nfo->max_size); + err = snd_pcm_hw_params_get_buffer_size_max (hw_params, &max_bufz); if (err < 0) { errmsg = "Cannot get maximum buffer size"; goto error_out; } + + err = snd_pcm_hw_params_get_periods_min (hw_params, &min_nper, 0); + if (err < 0) { + errmsg = "Cannot get minimum period count"; + goto error_out; + } + err = snd_pcm_hw_params_get_periods_max (hw_params, &max_nper, 0); + if (err < 0) { + errmsg = "Cannot get maximum period count"; + goto error_out; + } + snd_pcm_close (pcm); + + /* see also libs/backends/alsa/zita-alsa-pcmi.cc + * If any debug parameter is set, print device info. + */ + if (getenv ("ZITA_ALSA_PCMI_DEBUG")) { + fprintf (stdout, "ALSA: *%s* device-info\n", play ? "playback" : "capture"); + fprintf (stdout, " dev_name : %s\n", device_name); + fprintf (stdout, " channels : %u\n", nfo->max_channels); + fprintf (stdout, " min_rate : %u\n", nfo->min_rate); + fprintf (stdout, " max_rate : %u\n", nfo->max_rate); + fprintf (stdout, " min_psiz : %lu\n", nfo->min_size); + fprintf (stdout, " max_psiz : %lu\n", nfo->max_size); + fprintf (stdout, " min_bufz : %lu\n", min_bufz); + fprintf (stdout, " max_bufz : %lu\n", max_bufz); + fprintf (stdout, " min_nper : %d\n", min_nper); + fprintf (stdout, " max_nper : %d\n", max_nper); + fprintf (stdout, " possible : %lu .. %lu\n", nfo->min_size, nfo->max_size); + } + + /* AlsaAudioBackend supports n-periods 2, 3 */ + if (min_nper > 2 || max_nper < 3) { + errmsg = "Unsupported period count"; + return 1; + } + + nfo->min_size = std::max (min_psiz, min_bufz / 3); + nfo->max_size = std::min (max_psiz, max_bufz / 2); nfo->valid = true; return 0; |