23 Mar
2017
23 Mar
'17
4:31 p.m.
* HAD space reflects the actual data that is transferred. * Use the position buffer for capture, as DPIB write gets * completed earlier than the actual data written to the DDR.
** For capture stream following workaround is required to fix the* incorrect position reporting.** 1. Wait for 20us before reading the DMA position in buffer once* the interrupt is generated for stream completion.is this really 20us regardless of the sampling frequency/channel count? 20us is one sample at 48kHz so wondering how generic this work-around is...
Yes, this is independent of PCM parameters. Update happens on the HDA frame boundary i.e. 20.833uSec.
Makes sense. it's worth updating the comments though to make it self-explanatory.