ASoC: Add initial support for multiple CPU DAIs

ASoC core supports multiple codec DAIs but supports only a CPU DAI.
To support multiple cpu DAIs, add cpu_dai and num_cpu_dai in
snd_soc_dai_link and snd_soc_pcm_runtime structures similar to
support for codec_dai. This is intended as a preparatory patch to
eventually support the unification of the Codec and CPU DAI.

Inline with multiple codec DAI approach, add support to allocate,
init, bind and probe multiple cpu_dai on init if driver specifies
that. Also add support to loop over multiple cpu_dai during
suspend and resume.

This is intended as a preparatory patch to eventually unify the CPU
and Codec DAI into DAI components.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Link: https://lore.kernel.org/r/20200225133917.21314-2-yung-chuan.liao@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/sound/soc.h

@@ -855,6 +855,11 @@ struct snd_soc_dai_link {
 	     ((platform) = &link->platforms[i]);			\
 	     (i)++)
 
+#define for_each_link_cpus(link, i, cpu)				\
+	for ((i) = 0;							\
+	     ((i) < link->num_cpus) && ((cpu) = &link->cpus[i]);	\
+	     (i)++)
+
 /*
  * Sample 1 : Single CPU/Codec/Platform
  *
@@ -1132,6 +1137,9 @@ struct snd_soc_pcm_runtime {
 	struct snd_soc_dai **codec_dais;
 	unsigned int num_codecs;
 
+	struct snd_soc_dai **cpu_dais;
+	unsigned int num_cpus;
+
 	struct delayed_work delayed_work;
 	void (*close_delayed_work_func)(struct snd_soc_pcm_runtime *rtd);
 #ifdef CONFIG_DEBUG_FS
@@ -1159,6 +1167,13 @@ struct snd_soc_pcm_runtime {
 #define for_each_rtd_codec_dai_rollback(rtd, i, dai)		\
 	for (; (--(i) >= 0) && ((dai) = rtd->codec_dais[i]);)
 
+#define for_each_rtd_cpu_dai(rtd, i, dai)\
+	for ((i) = 0;						       \
+	     ((i) < rtd->num_cpus) && ((dai) = rtd->cpu_dais[i]); \
+	     (i)++)
+#define for_each_rtd_cpu_dai_rollback(rtd, i, dai)		\
+	for (; (--(i) >= 0) && ((dai) = rtd->cpu_dais[i]);)
+
 void snd_soc_close_delayed_work(struct snd_soc_pcm_runtime *rtd);
 
 /* mixer control */

sound/soc/soc-core.c

@@ -483,6 +483,14 @@ static struct snd_soc_pcm_runtime *soc_new_pcm_runtime(
 	if (!rtd->codec_dais)
 		goto free_rtd;
 
+	/*
+	 * for rtd->cpu_dais
+	 */
+	rtd->cpu_dais = devm_kcalloc(dev, dai_link->num_cpus,
+				     sizeof(struct snd_soc_dai *),
+				     GFP_KERNEL);
+	if (!rtd->cpu_dais)
+		goto free_rtd;
 	/*
 	 * rtd remaining settings
 	 */
@@ -833,7 +841,7 @@ static int soc_dai_link_sanity_check(struct snd_soc_card *card,
 				     struct snd_soc_dai_link *link)
 {
 	int i;
-	struct snd_soc_dai_link_component *codec, *platform;
+	struct snd_soc_dai_link_component *cpu, *codec, *platform;
 
 	for_each_link_codecs(link, i, codec) {
 		/*
@@ -882,44 +890,38 @@ static int soc_dai_link_sanity_check(struct snd_soc_card *card,
 			return -EPROBE_DEFER;
 	}
 
-	/* FIXME */
-	if (link->num_cpus > 1) {
-		dev_err(card->dev,
-			"ASoC: multi cpu is not yet supported %s\n",
-			link->name);
-		return -EINVAL;
-	}
-
-	/*
-	 * CPU device may be specified by either name or OF node, but
-	 * can be left unspecified, and will be matched based on DAI
-	 * name alone..
-	 */
-	if (link->cpus->name && link->cpus->of_node) {
-		dev_err(card->dev,
-			"ASoC: Neither/both cpu name/of_node are set for %s\n",
-			link->name);
-		return -EINVAL;
-	}
+	for_each_link_cpus(link, i, cpu) {
+		/*
+		 * CPU device may be specified by either name or OF node, but
+		 * can be left unspecified, and will be matched based on DAI
+		 * name alone..
+		 */
+		if (cpu->name && cpu->of_node) {
+			dev_err(card->dev,
+				"ASoC: Neither/both cpu name/of_node are set for %s\n",
+				link->name);
+			return -EINVAL;
+		}
 
-	/*
-	 * Defer card registration if cpu dai component is not added to
-	 * component list.
-	 */
-	if ((link->cpus->of_node || link->cpus->name) &&
-	    !soc_find_component(link->cpus))
-		return -EPROBE_DEFER;
+		/*
+		 * Defer card registration if cpu dai component is not added to
+		 * component list.
+		 */
+		if ((cpu->of_node || cpu->name) &&
+		    !soc_find_component(cpu))
+			return -EPROBE_DEFER;
 
-	/*
-	 * At least one of CPU DAI name or CPU device name/node must be
-	 * specified
-	 */
-	if (!link->cpus->dai_name &&
-	    !(link->cpus->name || link->cpus->of_node)) {
-		dev_err(card->dev,
-			"ASoC: Neither cpu_dai_name nor cpu_name/of_node are set for %s\n",
-			link->name);
-		return -EINVAL;
+		/*
+		 * At least one of CPU DAI name or CPU device name/node must be
+		 * specified
+		 */
+		if (!cpu->dai_name &&
+		    !(cpu->name || cpu->of_node)) {
+			dev_err(card->dev,
+				"ASoC: Neither cpu_dai_name nor cpu_name/of_node are set for %s\n",
+				link->name);
+			return -EINVAL;
+		}
 	}
 
 	return 0;
@@ -962,7 +964,7 @@ int snd_soc_add_pcm_runtime(struct snd_soc_card *card,
 			    struct snd_soc_dai_link *dai_link)
 {
 	struct snd_soc_pcm_runtime *rtd;
-	struct snd_soc_dai_link_component *codec, *platform;
+	struct snd_soc_dai_link_component *codec, *platform, *cpu;
 	struct snd_soc_component *component;
 	int i, ret;
 
@@ -987,14 +989,19 @@ int snd_soc_add_pcm_runtime(struct snd_soc_card *card,
 	if (!rtd)
 		return -ENOMEM;
 
-	/* FIXME: we need multi CPU support in the future */
-	rtd->cpu_dai = snd_soc_find_dai(dai_link->cpus);
-	if (!rtd->cpu_dai) {
-		dev_info(card->dev, "ASoC: CPU DAI %s not registered\n",
-			 dai_link->cpus->dai_name);
-		goto _err_defer;
+	rtd->num_cpus = dai_link->num_cpus;
+	for_each_link_cpus(dai_link, i, cpu) {
+		rtd->cpu_dais[i] = snd_soc_find_dai(cpu);
+		if (!rtd->cpu_dais[i]) {
+			dev_info(card->dev, "ASoC: CPU DAI %s not registered\n",
+				 cpu->dai_name);
+			goto _err_defer;
+		}
+		snd_soc_rtd_add_component(rtd, rtd->cpu_dais[i]->component);
 	}
-	snd_soc_rtd_add_component(rtd, rtd->cpu_dai->component);
+
+	/* Single cpu links expect cpu and cpu_dai in runtime data */
+	rtd->cpu_dai = rtd->cpu_dais[0];
 
 	/* Find CODEC from registered CODECs */
 	rtd->num_codecs = dai_link->num_codecs;
@@ -1114,7 +1121,8 @@ static int soc_init_pcm_runtime(struct snd_soc_card *card,
 			dai_link->stream_name, ret);
 		return ret;
 	}
-	ret = soc_dai_pcm_new(&cpu_dai, 1, rtd);
+	ret = soc_dai_pcm_new(rtd->cpu_dais,
+			      rtd->num_cpus, rtd);
 	if (ret < 0)
 		return ret;
 	ret = soc_dai_pcm_new(rtd->codec_dais,
@@ -1306,6 +1314,7 @@ static void soc_remove_link_dais(struct snd_soc_card *card)
 {
 	int i;
 	struct snd_soc_dai *codec_dai;
+	struct snd_soc_dai *cpu_dai;
 	struct snd_soc_pcm_runtime *rtd;
 	int order;
 
@@ -1315,14 +1324,15 @@ static void soc_remove_link_dais(struct snd_soc_card *card)
 			for_each_rtd_codec_dai(rtd, i, codec_dai)
 				soc_remove_dai(codec_dai, order);
 
-			soc_remove_dai(rtd->cpu_dai, order);
+			for_each_rtd_cpu_dai(rtd, i, cpu_dai)
+				soc_remove_dai(cpu_dai, order);
 		}
 	}
 }
 
 static int soc_probe_link_dais(struct snd_soc_card *card)
 {
-	struct snd_soc_dai *codec_dai;
+	struct snd_soc_dai *codec_dai, *cpu_dai;
 	struct snd_soc_pcm_runtime *rtd;
 	int i, order, ret;
 
@@ -1333,9 +1343,12 @@ static int soc_probe_link_dais(struct snd_soc_card *card)
 				"ASoC: probe %s dai link %d late %d\n",
 				card->name, rtd->num, order);
 
-			ret = soc_probe_dai(rtd->cpu_dai, order);
-			if (ret)
-				return ret;
+			/* probe the CPU DAI */
+			for_each_rtd_cpu_dai(rtd, i, cpu_dai) {
+				ret = soc_probe_dai(cpu_dai, order);
+				if (ret)
+					return ret;
+			}
 
 			/* probe the CODEC DAI */
 			for_each_rtd_codec_dai(rtd, i, codec_dai) {
@@ -1467,8 +1480,9 @@ static void soc_remove_aux_devices(struct snd_soc_card *card)
 int snd_soc_runtime_set_dai_fmt(struct snd_soc_pcm_runtime *rtd,
 	unsigned int dai_fmt)
 {
-	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
+	struct snd_soc_dai *cpu_dai;
 	struct snd_soc_dai *codec_dai;
+	unsigned int inv_dai_fmt;
 	unsigned int i;
 	int ret;
 
@@ -1485,33 +1499,33 @@ int snd_soc_runtime_set_dai_fmt(struct snd_soc_pcm_runtime *rtd,
 	 * Flip the polarity for the "CPU" end of a CODEC<->CODEC link
 	 * the component which has non_legacy_dai_naming is Codec
 	 */
-	if (cpu_dai->component->driver->non_legacy_dai_naming) {
-		unsigned int inv_dai_fmt;
-
-		inv_dai_fmt = dai_fmt & ~SND_SOC_DAIFMT_MASTER_MASK;
-		switch (dai_fmt & SND_SOC_DAIFMT_MASTER_MASK) {
-		case SND_SOC_DAIFMT_CBM_CFM:
-			inv_dai_fmt |= SND_SOC_DAIFMT_CBS_CFS;
-			break;
-		case SND_SOC_DAIFMT_CBM_CFS:
-			inv_dai_fmt |= SND_SOC_DAIFMT_CBS_CFM;
-			break;
-		case SND_SOC_DAIFMT_CBS_CFM:
-			inv_dai_fmt |= SND_SOC_DAIFMT_CBM_CFS;
-			break;
-		case SND_SOC_DAIFMT_CBS_CFS:
-			inv_dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
-			break;
-		}
-
-		dai_fmt = inv_dai_fmt;
+	inv_dai_fmt = dai_fmt & ~SND_SOC_DAIFMT_MASTER_MASK;
+	switch (dai_fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		inv_dai_fmt |= SND_SOC_DAIFMT_CBS_CFS;
+		break;
+	case SND_SOC_DAIFMT_CBM_CFS:
+		inv_dai_fmt |= SND_SOC_DAIFMT_CBS_CFM;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFM:
+		inv_dai_fmt |= SND_SOC_DAIFMT_CBM_CFS;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		inv_dai_fmt |= SND_SOC_DAIFMT_CBM_CFM;
+		break;
 	}
+	for_each_rtd_cpu_dai(rtd, i, cpu_dai) {
+		unsigned int fmt = dai_fmt;
 
-	ret = snd_soc_dai_set_fmt(cpu_dai, dai_fmt);
-	if (ret != 0 && ret != -ENOTSUPP) {
-		dev_warn(cpu_dai->dev,
-			 "ASoC: Failed to set DAI format: %d\n", ret);
-		return ret;
+		if (cpu_dai->component->driver->non_legacy_dai_naming)
+			fmt = inv_dai_fmt;
+
+		ret = snd_soc_dai_set_fmt(cpu_dai, fmt);
+		if (ret != 0 && ret != -ENOTSUPP) {
+			dev_warn(cpu_dai->dev,
+				 "ASoC: Failed to set DAI format: %d\n", ret);
+			return ret;
+		}
 	}
 
 	return 0;