During system suspend, the PM framework will freeze all applications and
the ALSA/ASoC core will suspend all RUNNING PCM streams.

However, D0ix-compatible PCM streams should keep the related pipelines
active in the DSP when the system is entering S0ix. The TRIGGER_SUSPEND
event is trapped in such cases to prevent the pipelines from being
stopped. Likewise, the TRIGGER_RESUME/START events should not affect the
pipeline state.

The SOF driver also triggers some DSP Firmware pipelines based on the
DAPM widgets power events. In such cases, we also ignore PRE_PMU and
POST_PMD events to keep the pipelines active.
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191025224122.7718-23-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>