On Thu, 26 Jul 2018 16:19:19 +0200, Rob Duncan wrote: > > > At 00:04 on Thu, Jul 26 2018, Takashi wrote: > >> Is it required that all available data has been committed between calls > >> to snd_pcm_ioplug_avail_update() on an IO plugin capture stream? > > > > Yes, the capture data is committed. > > The snd_pcm_ioplug_hw_ptr_update() should have reported the amount of > > data the slave PCM can actually transfer. Hence the transfer call > > thereafter must fulfill the whole requested data. > > But what I see is that snd_pcm_rate_avail_update() commits data in the > slave PCM in units of slave->period_size (via > snd_pcm_rate_grab_next_period()), which means that if there is a partial > period in the slave PCM mmap it will not be committed. > > In other words, not all the available data will be commmitted before the > next call to snd_pcm_ioplug_avail_update(). This means that the data > will be discarded the next time that snd_pcm_ioplug_avail_update() is > called. OK, I seem to have misunderstood about what you meant as committed in the context. Yes, if the available is partial, it might be not committed. But I don't understand the next part. How will it be discarded at the next snd_pcm_ioplug_avail_update()? The data remains on the buffer, and applptr isn't changed. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
