ASoC: SOF: Intel: hda: reserve host DMA channel for hostless streams

Due to the HW programming sequence requirement that the host
and link DMA channels need to be coupled/decoupled during pcm
hw_params, the host DMA channel corresponding to the link
DMA channel in use for hostless streams needs to be reserved.
This is achieved by adding a host_reserved flag in the
sof_intel_hda_stream structure which is checked when assigning
a host DMA channel.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/hda.h

@@ -413,6 +413,7 @@ struct sof_intel_hda_stream {
 	struct hdac_ext_stream hda_stream;
 	struct sof_intel_stream stream;
 	int hw_params_upon_resume; /* set up hw_params upon resume */
+	int host_reserved; /* reserve host DMA channel */
 };
 
 #define hstream_to_sof_hda_stream(hstream) \