ASoC: SOF: ipc4-pcm: support multiple configs for BE DAIs

Backend DAIs may support multiple audio formats. Modify pipeline
setup to select a suitable configuration based on topology and
frontend DAI runtime configuration.

For sampling rate, if one of the BE DAI configurations has
a sampling rate matching that of FE DAI, configure BE DAI to
this rate.

For sample format, the current code hardcodes DAI copier sample format
to 32bit for both playback and capture pipelines. This is not always
desired, so lift the limitation and set the sample format based on
topology definitions for the copiers. For capture pipelines, we want to
set the BE DAI pipeline format based on topology instead of using the FE
DAI format. This covers the common use-case where BE DAI outputs data at
a higher sample precision and sample width is reduced later in the
pipeline. Instead of hardcoding to 32bit, use the BE DAI copier output
format defined in topology.
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20230316141458.13940-2-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/ipc4-pcm.c

@@ -362,15 +362,68 @@ static void ipc4_ssp_dai_config_pcm_params_match(struct snd_sof_dev *sdev, const
 	}
 }
 
+/*
+ * Fixup DAI link parameters for sampling rate based on
+ * DAI copier configuration.
+ */
+static int sof_ipc4_pcm_dai_link_fixup_rate(struct snd_sof_dev *sdev,
+					    struct snd_pcm_hw_params *params,
+					    struct sof_ipc4_copier *ipc4_copier)
+{
+	struct sof_ipc4_pin_format *pin_fmts = ipc4_copier->available_fmt.input_pin_fmts;
+	struct snd_interval *rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+	int num_input_formats = ipc4_copier->available_fmt.num_input_formats;
+	unsigned int fe_rate = params_rate(params);
+	bool fe_be_rate_match = false;
+	bool single_be_rate = true;
+	unsigned int be_rate;
+	int i;
+
+	/*
+	 * Copier does not change sampling rate, so we
+	 * need to only consider the input pin information.
+	 */
+	for (i = 0; i < num_input_formats; i++) {
+		unsigned int val = pin_fmts[i].audio_fmt.sampling_frequency;
+
+		if (i == 0)
+			be_rate = val;
+		else if (val != be_rate)
+			single_be_rate = false;
+
+		if (val == fe_rate) {
+			fe_be_rate_match = true;
+			break;
+		}
+	}
+
+	/*
+	 * If rate is different than FE rate, topology must
+	 * contain an SRC. But we do require topology to
+	 * define a single rate in the DAI copier config in
+	 * this case (FE rate may be variable).
+	 */
+	if (!fe_be_rate_match) {
+		if (!single_be_rate) {
+			dev_err(sdev->dev, "Unable to select sampling rate for DAI link\n");
+			return -EINVAL;
+		}
+
+		rate->min = be_rate;
+		rate->max = rate->min;
+	}
+
+	return 0;
+}
+
 static int sof_ipc4_pcm_dai_link_fixup(struct snd_soc_pcm_runtime *rtd,
 				       struct snd_pcm_hw_params *params)
 {
 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, SOF_AUDIO_PCM_DRV_NAME);
 	struct snd_sof_dai *dai = snd_sof_find_dai(component, rtd->dai_link->name);
-	struct snd_interval *rate = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
-	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
 	struct snd_sof_dev *sdev = snd_soc_component_get_drvdata(component);
 	struct sof_ipc4_copier *ipc4_copier;
+	int ret;
 
 	if (!dai) {
 		dev_err(component->dev, "%s: No DAI found with name %s\n", __func__,
@@ -385,12 +438,9 @@ static int sof_ipc4_pcm_dai_link_fixup(struct snd_soc_pcm_runtime *rtd,
 		return -EINVAL;
 	}
 
-	/* always set BE format to 32-bits for both playback and capture */
-	snd_mask_none(fmt);
-	snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S32_LE);
-
-	rate->min = ipc4_copier->available_fmt.input_pin_fmts->audio_fmt.sampling_frequency;
-	rate->max = rate->min;
+	ret = sof_ipc4_pcm_dai_link_fixup_rate(sdev, params, ipc4_copier);
+	if (ret)
+		return ret;
 
 	switch (ipc4_copier->dai_type) {
 	case SOF_DAI_INTEL_SSP:

sound/soc/sof/ipc4-topology.c

@@ -1069,6 +1069,69 @@ static int snd_sof_get_nhlt_endpoint_data(struct snd_sof_dev *sdev, struct snd_s
 }
 #endif
 
+static int ipc4_set_fmt_mask(struct snd_mask *fmt, unsigned int bit_depth)
+{
+	switch (bit_depth) {
+	case 16:
+		snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S16_LE);
+		break;
+	case 24:
+		snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S24_LE);
+		break;
+	case 32:
+		snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S32_LE);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int ipc4_copier_set_capture_fmt(struct snd_sof_dev *sdev,
+				       struct snd_pcm_hw_params *pipeline_params,
+				       struct snd_pcm_hw_params *fe_params,
+				       struct sof_ipc4_available_audio_format *available_fmt)
+{
+	struct sof_ipc4_audio_format *audio_fmt;
+	unsigned int sample_valid_bits;
+	bool multiple_formats = false;
+	bool fe_format_match = false;
+	struct snd_mask *fmt;
+	int i;
+
+	for (i = 0; i < available_fmt->num_output_formats; i++) {
+		unsigned int val;
+
+		audio_fmt = &available_fmt->output_pin_fmts[i].audio_fmt;
+		val = SOF_IPC4_AUDIO_FORMAT_CFG_V_BIT_DEPTH(audio_fmt->fmt_cfg);
+
+		if (i == 0)
+			sample_valid_bits = val;
+		else if (sample_valid_bits != val)
+			multiple_formats = true;
+
+		if (snd_pcm_format_width(params_format(fe_params)) == val)
+			fe_format_match = true;
+	}
+
+	fmt = hw_param_mask(pipeline_params, SNDRV_PCM_HW_PARAM_FORMAT);
+	snd_mask_none(fmt);
+
+	if (multiple_formats) {
+		if (fe_format_match) {
+			/* multiple formats defined and one matches FE */
+			snd_mask_set_format(fmt, params_format(fe_params));
+			return 0;
+		}
+
+		dev_err(sdev->dev, "Multiple audio formats for single dai_out not supported\n");
+		return -EINVAL;
+	}
+
+	return ipc4_set_fmt_mask(fmt, sample_valid_bits);
+}
+
 static int
 sof_ipc4_prepare_copier_module(struct snd_sof_widget *swidget,
 			       struct snd_pcm_hw_params *fe_params,
@@ -1152,13 +1215,10 @@ sof_ipc4_prepare_copier_module(struct snd_sof_widget *swidget,
 			format_list_to_search = available_fmt->output_pin_fmts;
 			format_list_count = available_fmt->num_output_formats;
 
-			/*
-			 * modify the input params for the dai copier as it only supports
-			 * 32-bit always
-			 */
-			fmt = hw_param_mask(pipeline_params, SNDRV_PCM_HW_PARAM_FORMAT);
-			snd_mask_none(fmt);
-			snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S32_LE);
+			ret = ipc4_copier_set_capture_fmt(sdev, pipeline_params, fe_params,
+							  available_fmt);
+			if (ret < 0)
+				return ret;
 		} else {
 			format_list_to_search = available_fmt->input_pin_fmts;
 			format_list_count = available_fmt->num_input_formats;