[PATCH 5/8] ASoC: SOF: Intel: enable DMI L1 when pause is not supported

[Pierre-Louis Bossart]

DMI L1 entry is incompatible with pause on a capture stream, so if
pause is not supported we can enable DMI L1 unconditionally.

Experimental results show an increased residency in higher C states
and a significant decrease of system power consumption for "work from
home" usages such as VoIP calls.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen at linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan at linux.intel.com>
---
 sound/soc/sof/intel/hda-pcm.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/sound/soc/sof/intel/hda-pcm.c b/sound/soc/sof/intel/hda-pcm.c
index 47ff2c757d0a..aaa7686c00ee 100644
--- a/sound/soc/sof/intel/hda-pcm.c
+++ b/sound/soc/sof/intel/hda-pcm.c
@@ -221,6 +221,7 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
 		     struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct snd_soc_component *scomp = sdev->component;
 	struct hdac_ext_stream *dsp_stream;
 	struct snd_sof_pcm *spcm;
@@ -233,7 +234,13 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
 		return -EINVAL;
 	}
 
-	/* All playback and D0i3 compatible streams are DMI L1 capable */
+	/*
+	 * All playback and D0i3 compatible streams are DMI L1 capable, others need
+	 * pause push/release to be disabled
+	 */
+	if (!(runtime->hw.info & SNDRV_PCM_INFO_PAUSE))
+		hda_always_enable_dmi_l1 = true;
+
 	if (hda_always_enable_dmi_l1 ||
 	    direction == SNDRV_PCM_STREAM_PLAYBACK ||
 	    spcm->stream[substream->stream].d0i3_compatible)
-- 
2.25.1