[alsa-devel] period_time in slave definition

[Pavel Hofman]

Hi,

According to
http://www.alsa-project.org/alsa-doc/alsa-lib/pcm_plugins.html , my
.asoundrc contains:

pcm.test {
        type plug
        slave {
                pcm "hw:0"
                format "unchanged"
                channels "unchanged"
                rate "unchanged"
                period_size 1024
                buffer_size 4096
        }
}


While pcm, format, channels, and rate are accepted, the period and
buffer fields are refused:

ALSA lib pcm.c:6811:(snd_pcm_slave_conf) Unknown field period_time

I checked the source code and the keywords seem to be ok

pcm.c:
static const char *const names[SND_PCM_HW_PARAM_LAST_INTERVAL + 1] = {
	[SND_PCM_HW_PARAM_FORMAT] = "format",
	[SND_PCM_HW_PARAM_CHANNELS] = "channels",
	[SND_PCM_HW_PARAM_RATE] = "rate",
	[SND_PCM_HW_PARAM_PERIOD_TIME] = "period_time",
	[SND_PCM_HW_PARAM_PERIOD_SIZE] = "period_size",
	[SND_PCM_HW_PARAM_BUFFER_TIME] = "buffer_time",
	[SND_PCM_HW_PARAM_BUFFER_SIZE] = "buffer_size",
	[SND_PCM_HW_PARAM_PERIODS] = "periods"
};


Has any change been introduced recently which is not reflected on wiki
yet? Is there a way to specify "default" period and buffer parameters?

Thanks a lot,

Pavel.