ASoC: SOF: compress: Add support for computing timestamps

We compute the number of pcm_io_frames by dividing the
dai position to size of a frame (channels * sample size).
Reviewed-by: Paul Olaru <paul.olaru@oss.nxp.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/20220817080529.10864-5-daniel.baluta@oss.nxp.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/compress.c

@@ -327,10 +327,21 @@ static int sof_compr_pointer(struct snd_soc_component *component,
 			     struct snd_compr_stream *cstream,
 			     struct snd_compr_tstamp *tstamp)
 {
+	u64 dai_posn;
+	struct snd_sof_pcm *spcm;
+	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
 	struct sof_compr_stream *sstream = cstream->runtime->private_data;
 
+	spcm = snd_sof_find_spcm_dai(component, rtd);
+	if (!spcm)
+		return -EINVAL;
+
+	dai_posn = spcm->stream[cstream->direction].posn.dai_posn;
+
 	tstamp->sampling_rate = sstream->sampling_rate;
 	tstamp->copied_total = sstream->copied_total;
+	tstamp->pcm_io_frames = div_u64(spcm->stream[cstream->direction].posn.dai_posn,
+					sstream->channels * sstream->sample_container_bytes);
 
 	return 0;
 }