The period size represents the size of the DMA descriptor. To ensure all
DMA descriptors start from a well-aligned address, the period size must
be divided by (sample size * maxburst), not just by maxburst.
This adjustment allows for computing a higher maxburst value, thereby
increasing the performance of the DMA transfer.
Previously, snd_pcm_lib_period_bytes() returned 0 because the runtime HW
parameters are computed after the hw_params() callbacks are used.
To address this, we now use params_*() functions to compute the period
size accurately. This change optimizes the DMA transfer performance by
ensuring proper alignment and efficient use of maxburst values.

[andrei.simion@microchip.com: Reword commit message and commit title.
Add macros with values for maximum DMA chunk size allowed.
Add DMA_BURST_ALIGNED preprocessor function to check the alignment of the
DMA burst]
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Signed-off-by: Andrei Simion <andrei.simion@microchip.com>
Link: https://patch.msgid.link/20240905095633.113784-1-andrei.simion@microchip.comSigned-off-by: Mark Brown <broonie@kernel.org>