ASoC: SOF: Intel: hda-pcm: Follow the pause_supported flag to drop PAUSE support

If the stream's pause_supported flag is false then mask out the PAUSE
support so user space will be prevented to use it.

Introduce a module parameter to ignore the pause_supported flag, named as
force_pause_support to allow testing of the PAUSE feature.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>

Author: ujfalusi

sound/soc/sof/intel/hda-pcm.c

@@ -37,6 +37,11 @@ static bool hda_disable_rewinds;
 module_param_named(disable_rewinds, hda_disable_rewinds, bool, 0444);
 MODULE_PARM_DESC(disable_rewinds, "SOF HDA disable rewinds");
 
+static bool hda_force_pause_support;
+module_param_named(hda_force_pause_support, hda_force_pause_support, bool, 0444);
+MODULE_PARM_DESC(hda_force_pause_support,
+		 "SOF HDA ignore pause_supported flag to allow pause operation");
+
 u32 hda_dsp_get_mult_div(struct snd_sof_dev *sdev, int rate)
 {
 	switch (rate) {
@@ -240,6 +245,14 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
 	if (hda_always_enable_dmi_l1 && direction == SNDRV_PCM_STREAM_CAPTURE)
 		runtime->hw.info &= ~SNDRV_PCM_INFO_PAUSE;
 
+	/*
+	 * Follow the hint (unless a module parameter is set to ignore it) and
+	 * disable the pause push/release support
+	 */
+	if (!hda_force_pause_support &&
+	    !spcm->stream[substream->stream].pause_supported)
+		runtime->hw.info &= ~SNDRV_PCM_INFO_PAUSE;
+
 	if (hda_always_enable_dmi_l1 ||
 	    direction == SNDRV_PCM_STREAM_PLAYBACK ||
 	    spcm->stream[substream->stream].d0i3_compatible)