ASoC: SOF: ipc4-pcm: Look for best matching hw_config for SSP

Instead of just looking for a hw_config with matching rate only it sounds
better to try to find the best matching configuration.

If we have multiple hw_configurations with the same rate, but each with
different format for example then we have been picking the first config
with the matching rate, which can be a problem and it wil depend on how
the configs are ordered.

Instead we should be trying to find the best match out of the configs
1. rate + format + channels are matching
2. rate + format are matching
3. rate matching

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

Author: ujfalusi

sound/soc/sof/ipc4-pcm.c

@@ -563,6 +563,8 @@ static void ipc4_ssp_dai_config_pcm_params_match(struct snd_sof_dev *sdev, const
 	struct snd_sof_dai_link *slink;
 	struct snd_sof_dai *dai;
 	bool dai_link_found = false;
+	int current_config = -1;
+	int matching_params = 0;
 	int i;
 
 	list_for_each_entry(slink, &sdev->dai_link_list, list) {
@@ -575,17 +577,48 @@ static void ipc4_ssp_dai_config_pcm_params_match(struct snd_sof_dev *sdev, const
 	if (!dai_link_found)
 		return;
 
+	/*
+	 * Find the first best matching hardware config:
+	 * rate + format + channels are matching
+	 * rate + format are matching
+	 * rate matching
+	 */
 	for (i = 0; i < slink->num_hw_configs; i++) {
 		struct snd_soc_tplg_hw_config *hw_config = &slink->hw_configs[i];
 
-		if (params_rate(params) == le32_to_cpu(hw_config->fsync_rate)) {
-			/* set current config for all DAI's with matching name */
-			list_for_each_entry(dai, &sdev->dai_list, list)
-				if (!strcmp(slink->link->name, dai->name))
-					dai->current_config = le32_to_cpu(hw_config->id);
+		if (params_rate(params) == le32_to_cpu(hw_config->fsync_rate) &&
+		    params_width(params) == le32_to_cpu(hw_config->tdm_slot_width) &&
+		    params_channels(params) == le32_to_cpu(hw_config->tdm_slots)) {
+			current_config = le32_to_cpu(hw_config->id);
+			matching_params = 3;
+			/* best match found */
 			break;
+		} else if (matching_params < 2 &&
+			   params_rate(params) == le32_to_cpu(hw_config->fsync_rate) &&
+			   params_width(params) == le32_to_cpu(hw_config->tdm_slot_width)) {
+			current_config = le32_to_cpu(hw_config->id);
+			matching_params = 2;
+			/* keep looking for better match */
+		} else if (matching_params < 1 &&
+			   params_rate(params) == le32_to_cpu(hw_config->fsync_rate)) {
+			current_config = le32_to_cpu(hw_config->id);
+			matching_params = 1;
+			/* keep looking for better match */
 		}
 	}
+
+	if (current_config < 0) {
+		dev_dbg(sdev->dev, "No suitable hw_config found for %s\n",
+			slink->link->name);
+		return;
+	}
+
+	dev_dbg(sdev->dev,
+		"hw_config for %s: %d (num_hw_configs: %d) with %d matching params\n",
+		slink->link->name, current_config, slink->num_hw_configs, matching_params);
+	list_for_each_entry(dai, &sdev->dai_list, list)
+		if (!strcmp(slink->link->name, dai->name))
+			dai->current_config = current_config;
 }
 
 /*