[PATCH 1/2] dmaengine: bcm2835: Fix cyclic DMA period splitting

Eric Anholt eric at anholt.net
Mon Jun 13 21:49:26 PDT 2016

Matthias Reichl <hias at horus.com> writes:

> The code responsible for splitting periods into chunks that
> can be handled by the DMA controller missed to update total_len,
> the number of bytes processed in the current period, when there
> are more chunks to follow.
> Therefore total_len was stuck at 0 and the code didn't work at all.
> This resulted in a wrong control block layout and audio issues because
> the cyclic DMA callback wasn't executing on period boundaries.
> Fix this by adding the missing total_len update.

It looks like this issue has been around for a long time, and this fix
is pretty dependent on the recent refactors.

Reviewed-by: Eric Anholt <eric at anholt.net>
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