* 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.
_______________________________________________
Alsa-devel mailing list
Alsa-devel@xxxxxxxxxxxxxxxx
http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
