Originally in commit b2ebcf42a4 ("ASoC: SOF: free widgets in
sof_tear_down_pipelines() for static pipelines"), freeing of pipeline
components at suspend was only done with recent FW as there were known
limitations in older firmware versions.
Tests show that if static pipelines are used, i.e. all pipelines are
setup whenever firmware is powered up, the reverse action of freeing all
components at power down, leads to firmware failures with also SOF2.0
and SOF2.1 based firmware.
The problems can be specific to certain topologies with e.g. components
not prepared to be freed at suspend (as this did not happen with older
SOF kernels).
To avoid hitting these problems when kernel is upgraded and used with an
older firmware, bump the firmware requirement to SOF2.2 or newer. If an
older firmware is used, and pipeline is a static one, do not free the
components at suspend. This ensures the suspend flow remains backwards
compatible with older firmware versions. This limitation does not apply
if the product configuration is updated to dynamic pipelines.
The limitation is not linked to firmware ABI, as the interface to free
pipeline components has been available already before ABI3.19. The
problem is in the implementation, so firmware version should be used to
decide whether it is safe to use the newer flow or not. This patch adds
a new SOF_FW_VER() macro to compare SOF firmware release versions.
Link: https://github.com/thesofproject/sof/issues/6475
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20221101114913.1292671-1-kai.vehmanen@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
003b786b67