[alsa-devel] [PATCH v2] ALSA: hda/ca0132 - Update latency based on DSP state.

Pierre-Louis Bossart pierre-louis.bossart at linux.intel.com
Fri Apr 5 17:01:04 CEST 2013

>> The DSP in the CA0132 codec adds a variable latency to audio depending
>> on what processing is being done.  Add a new patch op to return that
>> latency for capture and playback streams.  The latency is determined
>> by which blocks are enabled and knowing how much latency is added by
>> each block.
>> Signed-off-by: Dylan Reid <dgreid at chromium.org>
> Thanks, applied.

This conflicts with the audio timestamp stuff I contributed last year.
If the hardware supports a WALLCLK, and HDA does, the timestamp is just 
a read of the counter plus a translation to ns. If it doesn't, the 
timestamp corresponds to the delay. If you modify the definition of the 
delay then the timestamp will be off on some platforms.

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