Hi John,
Dne 14. 01. 20 v 21:04 John Keeping napsal(a):
I've taken a look at this and the patch below fixes it in my simple
testing.
I like your solution, simple and understandable.
But note that this doesn't adjust the PCM's min_period_bytes
which will be necessary if you want to minimize latency with an adjusted
high-speed bInterval setting.
My motivation for the smaller bInterval is higher attainable throughput.
In fact to reach stable operation (avoiding random xruns) I have to use
larger period on RPi4 - hence larger latency anyway.
I'm not sure what the right answer is for that; we could update
min_period_bytes if the PCM is opened after the gadget attaches, but
then if it is re-attached at a slower speed the PCM configuration will
be wrong.
I would suggest to keep the minimum period setting as is.
Thanks a lot for your help.
Pavel.
