On Mon, 1 Feb 2010, pl bossart wrote: > All, > I'd like to reopen a thread on concerns with the current > implementation of rewind in ALSA. This was already discussed on the > mailing list last year without any progress. I don't think that there have been no progress. The queued samples can be stored to runtime->delay now, so snd_pcm_delay() returns a correct value. The snd_pcm_rewind() and snd_pcm_forward() functions should operate in the ring buffer and it's ok. See the USB driver for an example. Just add support for runtime->delay to the lowlevel drivers and use snd_pcm_delay() correctly in the user space and everything will work as expected. In other words - for hardware with large FIFOs, the runtime->delay should be used for queued samples and the hw_ptr in the ring buffer should be increased as soon as the FIFO is filled with samples from the ring buffer. Jaroslav ----- Jaroslav Kysela <perex@xxxxxxxx> Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
