[alsa-devel] [PATCH 1/3] ALSA: pcm - introduce device_buffer

[Raymond Yau]

2012-8-31 上午9:08 於 "Vinod Koul" <vinod.koul at linux.intel.com> 寫道：
>
> In many modern SoCs the audio DSP can buffer the PCM ring buffer data,
typically
> in SRAMs or any other memory available.
> Today we have no means to represent this buffering and ALSA in some cases
when
> device still has to render this buffer but app_ptr is equal to hw_ptr alsa
> wrongly detects an overrun
>
> This patch tries to add a new field "device_buffer" to represent
buffering done in
> DSPs. This value is also used for the xrun calculations in ALSA
>
> Signed-off-by: Vinod Koul <vinod.koul at linux.intel.com>
> ---

are these buffer similar to hda 's FIFO ?

can the alsa application use snd_pcm_rewind to rewind the app_ptr ?