linux-phytec-ti

ASoC: davinci-mcasp: Add workaround for errata i868 (dra7xx family)

McASP FIFO events to eDMA or sDMA can be lost depending on the
timing between McASP side activity and DMA side activity, causing
overflow (capture) or underflow (playback).

The workaround consists of maximizing the time to avoid the
boundary condition in hardware.  So the RNUMEVT/WNUMEVT should be
set to the multiple of the active serializers that is less than
or equal to 32.

This errata is applicable for McASP IP revision < 3.3, which may
be present in other platforms.  But since the revision definition
is not consistent across those platforms, the errata workaround
is only set for DRA7xx family whose revision information is
known.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
CC: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>