ASoC: Change the PCM runtime array to a list

Currently the number of DAI links is statically defined by the machine
driver at build time using an array. This makes it difficult to shrink/
grow the number of DAI links at runtime in order to reflect any changes
in topology.

We can change the DAI link array in the core to a list so that PCMs and
FE DAI links can be added and deleted at runtime to reflect changes in
use case and DSP topology. The machine driver can still register DAI links
as an array.

As the 1st step, this patch change the PCM runtime array to a list. A new
PCM runtime is added to the list when a DAI link is bound successfully.

Later patches will further implement the DAI link list.

More:
- define snd_soc_new/free_pcm_runtime() to create/free a runtime.
- define soc_add_pcm_runtime() to add a runtime to the rtd list.
- define soc_remove_pcm_runtimes() to clean up the runtime list.

- traverse the rtd list to probe the link components and dais.

- Add a field "num" to PCM runtime struct, used to specify the device
  number when creating the pcm device, and for a soc card to access
  its dai_props array.

- The following 3rd party machine/platform drivers iterate the rtd list
  to check the runtimes:
  sound/soc/intel/atom/sst-mfld-platform-pcm.c
  sound/soc/intel/boards/cht_bsw_rt5645.c
  sound/soc/intel/boards/cht_bsw_rt5672.c
  sound/soc/intel/boards/cht_bsw_max98090_ti.c

Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 154 insertions, 109 deletions

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 24b096066a07..2c95de723d8f 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -537,26 +537,75 @@ static inline void snd_soc_debugfs_exit(void)
 struct snd_pcm_substream *snd_soc_get_dai_substream(struct snd_soc_card *card,
 		const char *dai_link, int stream)
 {
-	int i;
+	struct snd_soc_pcm_runtime *rtd;
 
-	for (i = 0; i < card->num_links; i++) {
-		if (card->rtd[i].dai_link->no_pcm &&
-			!strcmp(card->rtd[i].dai_link->name, dai_link))
-			return card->rtd[i].pcm->streams[stream].substream;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		if (rtd->dai_link->no_pcm &&
+			!strcmp(rtd->dai_link->name, dai_link))
+			return rtd->pcm->streams[stream].substream;
 	}
 	dev_dbg(card->dev, "ASoC: failed to find dai link %s\n", dai_link);
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(snd_soc_get_dai_substream);
 
+static struct snd_soc_pcm_runtime *soc_new_pcm_runtime(
+	struct snd_soc_card *card, struct snd_soc_dai_link *dai_link)
+{
+	struct snd_soc_pcm_runtime *rtd;
+
+	rtd = kzalloc(sizeof(struct snd_soc_pcm_runtime), GFP_KERNEL);
+	if (!rtd)
+		return NULL;
+
+	rtd->card = card;
+	rtd->dai_link = dai_link;
+	rtd->codec_dais = kzalloc(sizeof(struct snd_soc_dai *) *
+					dai_link->num_codecs,
+					GFP_KERNEL);
+	if (!rtd->codec_dais) {
+		kfree(rtd);
+		return NULL;
+	}
+
+	return rtd;
+}
+
+static void soc_free_pcm_runtime(struct snd_soc_pcm_runtime *rtd)
+{
+	if (rtd && rtd->codec_dais)
+		kfree(rtd->codec_dais);
+	kfree(rtd);
+}
+
+static void soc_add_pcm_runtime(struct snd_soc_card *card,
+		struct snd_soc_pcm_runtime *rtd)
+{
+	list_add_tail(&rtd->list, &card->rtd_list);
+	rtd->num = card->num_rtd;
+	card->num_rtd++;
+}
+
+static void soc_remove_pcm_runtimes(struct snd_soc_card *card)
+{
+	struct snd_soc_pcm_runtime *rtd, *_rtd;
+
+	list_for_each_entry_safe(rtd, _rtd, &card->rtd_list, list) {
+		list_del(&rtd->list);
+		soc_free_pcm_runtime(rtd);
+	}
+
+	card->num_rtd = 0;
+}
+
 struct snd_soc_pcm_runtime *snd_soc_get_pcm_runtime(struct snd_soc_card *card,
 		const char *dai_link)
 {
-	int i;
+	struct snd_soc_pcm_runtime *rtd;
 
-	for (i = 0; i < card->num_links; i++) {
-		if (!strcmp(card->rtd[i].dai_link->name, dai_link))
-			return &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		if (!strcmp(rtd->dai_link->name, dai_link))
+			return rtd;
 	}
 	dev_dbg(card->dev, "ASoC: failed to find rtd %s\n", dai_link);
 	return NULL;
@@ -578,7 +627,8 @@ int snd_soc_suspend(struct device *dev)
 {
 	struct snd_soc_card *card = dev_get_drvdata(dev);
 	struct snd_soc_codec *codec;
-	int i, j;
+	struct snd_soc_pcm_runtime *rtd;
+	int i;
 
 	/* If the card is not initialized yet there is nothing to do */
 	if (!card->instantiated)
@@ -595,13 +645,13 @@ int snd_soc_suspend(struct device *dev)
 	snd_power_change_state(card->snd_card, SNDRV_CTL_POWER_D3hot);
 
 	/* mute any active DACs */
-	for (i = 0; i < card->num_rtd; i++) {
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
-		for (j = 0; j < card->rtd[i].num_codecs; j++) {
-			struct snd_soc_dai *dai = card->rtd[i].codec_dais[j];
+		for (i = 0; i < rtd->num_codecs; i++) {
+			struct snd_soc_dai *dai = rtd->codec_dais[i];
 			struct snd_soc_dai_driver *drv = dai->driver;
 
 			if (drv->ops->digital_mute && dai->playback_active)
@@ -610,20 +660,20 @@ int snd_soc_suspend(struct device *dev)
 	}
 
 	/* suspend all pcms */
-	for (i = 0; i < card->num_rtd; i++) {
-		if (card->rtd[i].dai_link->ignore_suspend)
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
-		snd_pcm_suspend_all(card->rtd[i].pcm);
+		snd_pcm_suspend_all(rtd->pcm);
 	}
 
 	if (card->suspend_pre)
 		card->suspend_pre(card);
 
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_dai *cpu_dai = card->rtd[i].cpu_dai;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
 		if (cpu_dai->driver->suspend && !cpu_dai->driver->bus_control)
@@ -631,19 +681,19 @@ int snd_soc_suspend(struct device *dev)
 	}
 
 	/* close any waiting streams */
-	for (i = 0; i < card->num_rtd; i++)
-		flush_delayed_work(&card->rtd[i].delayed_work);
+	list_for_each_entry(rtd, &card->rtd_list, list)
+		flush_delayed_work(&rtd->delayed_work);
 
-	for (i = 0; i < card->num_rtd; i++) {
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
-		snd_soc_dapm_stream_event(&card->rtd[i],
+		snd_soc_dapm_stream_event(rtd,
 					  SNDRV_PCM_STREAM_PLAYBACK,
 					  SND_SOC_DAPM_STREAM_SUSPEND);
 
-		snd_soc_dapm_stream_event(&card->rtd[i],
+		snd_soc_dapm_stream_event(rtd,
 					  SNDRV_PCM_STREAM_CAPTURE,
 					  SND_SOC_DAPM_STREAM_SUSPEND);
 	}
@@ -690,10 +740,10 @@ int snd_soc_suspend(struct device *dev)
 		}
 	}
 
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_dai *cpu_dai = card->rtd[i].cpu_dai;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
 		if (cpu_dai->driver->suspend && cpu_dai->driver->bus_control)
@@ -717,8 +767,9 @@ static void soc_resume_deferred(struct work_struct *work)
 {
 	struct snd_soc_card *card =
 			container_of(work, struct snd_soc_card, deferred_resume_work);
+	struct snd_soc_pcm_runtime *rtd;
 	struct snd_soc_codec *codec;
-	int i, j;
+	int i;
 
 	/* our power state is still SNDRV_CTL_POWER_D3hot from suspend time,
 	 * so userspace apps are blocked from touching us
@@ -733,10 +784,10 @@ static void soc_resume_deferred(struct work_struct *work)
 		card->resume_pre(card);
 
 	/* resume control bus DAIs */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_dai *cpu_dai = card->rtd[i].cpu_dai;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
 		if (cpu_dai->driver->resume && cpu_dai->driver->bus_control)
@@ -751,28 +802,28 @@ static void soc_resume_deferred(struct work_struct *work)
 		}
 	}
 
-	for (i = 0; i < card->num_rtd; i++) {
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
-		snd_soc_dapm_stream_event(&card->rtd[i],
+		snd_soc_dapm_stream_event(rtd,
 					  SNDRV_PCM_STREAM_PLAYBACK,
 					  SND_SOC_DAPM_STREAM_RESUME);
 
-		snd_soc_dapm_stream_event(&card->rtd[i],
+		snd_soc_dapm_stream_event(rtd,
 					  SNDRV_PCM_STREAM_CAPTURE,
 					  SND_SOC_DAPM_STREAM_RESUME);
 	}
 
 	/* unmute any active DACs */
-	for (i = 0; i < card->num_rtd; i++) {
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
-		for (j = 0; j < card->rtd[i].num_codecs; j++) {
-			struct snd_soc_dai *dai = card->rtd[i].codec_dais[j];
+		for (i = 0; i < rtd->num_codecs; i++) {
+			struct snd_soc_dai *dai = rtd->codec_dais[i];
 			struct snd_soc_dai_driver *drv = dai->driver;
 
 			if (drv->ops->digital_mute && dai->playback_active)
@@ -780,10 +831,10 @@ static void soc_resume_deferred(struct work_struct *work)
 		}
 	}
 
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_dai *cpu_dai = card->rtd[i].cpu_dai;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 
-		if (card->rtd[i].dai_link->ignore_suspend)
+		if (rtd->dai_link->ignore_suspend)
 			continue;
 
 		if (cpu_dai->driver->resume && !cpu_dai->driver->bus_control)
@@ -808,15 +859,14 @@ int snd_soc_resume(struct device *dev)
 {
 	struct snd_soc_card *card = dev_get_drvdata(dev);
 	bool bus_control = false;
-	int i;
+	struct snd_soc_pcm_runtime *rtd;
 
 	/* If the card is not initialized yet there is nothing to do */
 	if (!card->instantiated)
 		return 0;
 
 	/* activate pins from sleep state */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_pcm_runtime *rtd = &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 		struct snd_soc_dai **codec_dais = rtd->codec_dais;
 		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 		int j;
@@ -837,8 +887,8 @@ int snd_soc_resume(struct device *dev)
 	 * have that problem and may take a substantial amount of time to resume
 	 * due to I/O costs and anti-pop so handle them out of line.
 	 */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_dai *cpu_dai = card->rtd[i].cpu_dai;
+	list_for_each_entry(rtd, &card->rtd_list, list) {
+		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 		bus_control |= cpu_dai->driver->bus_control;
 	}
 	if (bus_control) {
@@ -913,16 +963,20 @@ static struct snd_soc_dai *snd_soc_find_dai(
 static int soc_bind_dai_link(struct snd_soc_card *card, int num)
 {
 	struct snd_soc_dai_link *dai_link = &card->dai_link[num];
-	struct snd_soc_pcm_runtime *rtd = &card->rtd[num];
+	struct snd_soc_pcm_runtime *rtd;
 	struct snd_soc_dai_link_component *codecs = dai_link->codecs;
 	struct snd_soc_dai_link_component cpu_dai_component;
-	struct snd_soc_dai **codec_dais = rtd->codec_dais;
+	struct snd_soc_dai **codec_dais;
 	struct snd_soc_platform *platform;
 	const char *platform_name;
 	int i;
 
 	dev_dbg(card->dev, "ASoC: binding %s at idx %d\n", dai_link->name, num);
 
+	rtd = soc_new_pcm_runtime(card, dai_link);
+	if (!rtd)
+		return -ENOMEM;
+
 	cpu_dai_component.name = dai_link->cpu_name;
 	cpu_dai_component.of_node = dai_link->cpu_of_node;
 	cpu_dai_component.dai_name = dai_link->cpu_dai_name;
@@ -930,18 +984,19 @@ static int soc_bind_dai_link(struct snd_soc_card *card, int num)
 	if (!rtd->cpu_dai) {
 		dev_err(card->dev, "ASoC: CPU DAI %s not registered\n",
 			dai_link->cpu_dai_name);
-		return -EPROBE_DEFER;
+		goto _err_defer;
 	}
 
 	rtd->num_codecs = dai_link->num_codecs;
 
 	/* Find CODEC from registered CODECs */
+	codec_dais = rtd->codec_dais;
 	for (i = 0; i < rtd->num_codecs; i++) {
 		codec_dais[i] = snd_soc_find_dai(&codecs[i]);
 		if (!codec_dais[i]) {
 			dev_err(card->dev, "ASoC: CODEC DAI %s not registered\n",
 				codecs[i].dai_name);
-			return -EPROBE_DEFER;
+			goto _err_defer;
 		}
 	}
 
@@ -973,9 +1028,12 @@ static int soc_bind_dai_link(struct snd_soc_card *card, int num)
 		return -EPROBE_DEFER;
 	}
 
-	card->num_rtd++;
-
+	soc_add_pcm_runtime(card, rtd);
 	return 0;
+
+_err_defer:
+	soc_free_pcm_runtime(rtd);
+	return  -EPROBE_DEFER;
 }
 
 static void soc_remove_component(struct snd_soc_component *component)
@@ -1014,9 +1072,9 @@ static void soc_remove_dai(struct snd_soc_dai *dai, int order)
 	}
 }
 
-static void soc_remove_link_dais(struct snd_soc_card *card, int num, int order)
+static void soc_remove_link_dais(struct snd_soc_card *card,
+		struct snd_soc_pcm_runtime *rtd, int order)
 {
-	struct snd_soc_pcm_runtime *rtd = &card->rtd[num];
 	int i;
 
 	/* unregister the rtd device */
@@ -1032,10 +1090,9 @@ static void soc_remove_link_dais(struct snd_soc_card *card, int num, int order)
 	soc_remove_dai(rtd->cpu_dai, order);
 }
 
-static void soc_remove_link_components(struct snd_soc_card *card, int num,
-				       int order)
+static void soc_remove_link_components(struct snd_soc_card *card,
+	struct snd_soc_pcm_runtime *rtd, int order)
 {
-	struct snd_soc_pcm_runtime *rtd = &card->rtd[num];
 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 	struct snd_soc_platform *platform = rtd->platform;
 	struct snd_soc_component *component;
@@ -1061,21 +1118,20 @@ static void soc_remove_link_components(struct snd_soc_card *card, int num,
 
 static void soc_remove_dai_links(struct snd_soc_card *card)
 {
-	int dai, order;
+	int order;
+	struct snd_soc_pcm_runtime *rtd;
 
 	for (order = SND_SOC_COMP_ORDER_FIRST; order <= SND_SOC_COMP_ORDER_LAST;
 			order++) {
-		for (dai = 0; dai < card->num_rtd; dai++)
-			soc_remove_link_dais(card, dai, order);
+		list_for_each_entry(rtd, &card->rtd_list, list)
+			soc_remove_link_dais(card, rtd, order);
 	}
 
 	for (order = SND_SOC_COMP_ORDER_FIRST; order <= SND_SOC_COMP_ORDER_LAST;
 			order++) {
-		for (dai = 0; dai < card->num_rtd; dai++)
-			soc_remove_link_components(card, dai, order);
+		list_for_each_entry(rtd, &card->rtd_list, list)
+			soc_remove_link_components(card, rtd, order);
 	}
-
-	card->num_rtd = 0;
 }
 
 static void soc_set_name_prefix(struct snd_soc_card *card,
@@ -1220,10 +1276,10 @@ static int soc_post_component_init(struct snd_soc_pcm_runtime *rtd,
 	return 0;
 }
 
-static int soc_probe_link_components(struct snd_soc_card *card, int num,
+static int soc_probe_link_components(struct snd_soc_card *card,
+			struct snd_soc_pcm_runtime *rtd,
 				     int order)
 {
-	struct snd_soc_pcm_runtime *rtd = &card->rtd[num];
 	struct snd_soc_platform *platform = rtd->platform;
 	struct snd_soc_component *component;
 	int i, ret;
@@ -1319,15 +1375,15 @@ static int soc_link_dai_widgets(struct snd_soc_card *card,
 	return 0;
 }
 
-static int soc_probe_link_dais(struct snd_soc_card *card, int num, int order)
+static int soc_probe_link_dais(struct snd_soc_card *card,
+		struct snd_soc_pcm_runtime *rtd, int order)
 {
-	struct snd_soc_dai_link *dai_link = &card->dai_link[num];
-	struct snd_soc_pcm_runtime *rtd = &card->rtd[num];
+	struct snd_soc_dai_link *dai_link = rtd->dai_link;
 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 	int i, ret;
 
 	dev_dbg(card->dev, "ASoC: probe %s dai link %d late %d\n",
-			card->name, num, order);
+			card->name, rtd->num, order);
 
 	/* set default power off timeout */
 	rtd->pmdown_time = pmdown_time;
@@ -1372,7 +1428,7 @@ static int soc_probe_link_dais(struct snd_soc_card *card, int num, int order)
 
 	if (cpu_dai->driver->compress_new) {
 		/*create compress_device"*/
-		ret = cpu_dai->driver->compress_new(rtd, num);
+		ret = cpu_dai->driver->compress_new(rtd, rtd->num);
 		if (ret < 0) {
 			dev_err(card->dev, "ASoC: can't create compress %s\n",
 					 dai_link->stream_name);
@@ -1382,7 +1438,7 @@ static int soc_probe_link_dais(struct snd_soc_card *card, int num, int order)
 
 		if (!dai_link->params) {
 			/* create the pcm */
-			ret = soc_new_pcm(rtd, num);
+			ret = soc_new_pcm(rtd, rtd->num);
 			if (ret < 0) {
 				dev_err(card->dev, "ASoC: can't create pcm %s :%d\n",
 				       dai_link->stream_name, ret);
@@ -1552,6 +1608,7 @@ EXPORT_SYMBOL_GPL(snd_soc_runtime_set_dai_fmt);
 static int snd_soc_instantiate_card(struct snd_soc_card *card)
 {
 	struct snd_soc_codec *codec;
+	struct snd_soc_pcm_runtime *rtd;
 	int ret, i, order;
 
 	mutex_lock(&client_mutex);
@@ -1624,8 +1681,8 @@ static int snd_soc_instantiate_card(struct snd_soc_card *card)
 	/* probe all components used by DAI links on this card */
 	for (order = SND_SOC_COMP_ORDER_FIRST; order <= SND_SOC_COMP_ORDER_LAST;
 			order++) {
-		for (i = 0; i < card->num_links; i++) {
-			ret = soc_probe_link_components(card, i, order);
+		list_for_each_entry(rtd, &card->rtd_list, list) {
+			ret = soc_probe_link_components(card, rtd, order);
 			if (ret < 0) {
 				dev_err(card->dev,
 					"ASoC: failed to instantiate card %d\n",
@@ -1638,8 +1695,8 @@ static int snd_soc_instantiate_card(struct snd_soc_card *card)
 	/* probe all DAI links on this card */
 	for (order = SND_SOC_COMP_ORDER_FIRST; order <= SND_SOC_COMP_ORDER_LAST;
 			order++) {
-		for (i = 0; i < card->num_links; i++) {
-			ret = soc_probe_link_dais(card, i, order);
+		list_for_each_entry(rtd, &card->rtd_list, list) {
+			ret = soc_probe_link_dais(card, rtd, order);
 			if (ret < 0) {
 				dev_err(card->dev,
 					"ASoC: failed to instantiate card %d\n",
@@ -1733,6 +1790,7 @@ card_probe_error:
 	snd_card_free(card->snd_card);
 
 base_error:
+	soc_remove_pcm_runtimes(card);
 	mutex_unlock(&card->mutex);
 	mutex_unlock(&client_mutex);
 
@@ -1763,13 +1821,12 @@ static int soc_probe(struct platform_device *pdev)
 
 static int soc_cleanup_card_resources(struct snd_soc_card *card)
 {
+	struct snd_soc_pcm_runtime *rtd;
 	int i;
 
 	/* make sure any delayed work runs */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_pcm_runtime *rtd = &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list)
 		flush_delayed_work(&rtd->delayed_work);
-	}
 
 	/* remove auxiliary devices */
 	for (i = 0; i < card->num_aux_devs; i++)
@@ -1777,6 +1834,7 @@ static int soc_cleanup_card_resources(struct snd_soc_card *card)
 
 	/* remove and free each DAI */
 	soc_remove_dai_links(card);
+	soc_remove_pcm_runtimes(card);
 
 	soc_cleanup_card_debugfs(card);
 
@@ -1803,29 +1861,26 @@ static int soc_remove(struct platform_device *pdev)
 int snd_soc_poweroff(struct device *dev)
 {
 	struct snd_soc_card *card = dev_get_drvdata(dev);
-	int i;
+	struct snd_soc_pcm_runtime *rtd;
 
 	if (!card->instantiated)
 		return 0;
 
 	/* Flush out pmdown_time work - we actually do want to run it
 	 * now, we're shutting down so no imminent restart. */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_pcm_runtime *rtd = &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list)
 		flush_delayed_work(&rtd->delayed_work);
-	}
 
 	snd_soc_dapm_shutdown(card);
 
 	/* deactivate pins to sleep state */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_pcm_runtime *rtd = &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list) {
 		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
-		int j;
+		int i;
 
 		pinctrl_pm_select_sleep_state(cpu_dai->dev);
-		for (j = 0; j < rtd->num_codecs; j++) {
-			struct snd_soc_dai *codec_dai = rtd->codec_dais[j];
+		for (i = 0; i < rtd->num_codecs; i++) {
+			struct snd_soc_dai *codec_dai = rtd->codec_dais[i];
 			pinctrl_pm_select_sleep_state(codec_dai->dev);
 		}
 	}
@@ -2337,6 +2392,7 @@ static int snd_soc_init_multicodec(struct snd_soc_card *card,
 int snd_soc_register_card(struct snd_soc_card *card)
 {
 	int i, j, ret;
+	struct snd_soc_pcm_runtime *rtd;
 
 	if (!card->name || !card->dev)
 		return -EINVAL;
@@ -2408,25 +2464,15 @@ int snd_soc_register_card(struct snd_soc_card *card)
 
 	snd_soc_initialize_card_lists(card);
 
-	card->rtd = devm_kzalloc(card->dev,
+	INIT_LIST_HEAD(&card->rtd_list);
+	card->num_rtd = 0;
+
+	card->rtd_aux = devm_kzalloc(card->dev,
 				 sizeof(struct snd_soc_pcm_runtime) *
-				 (card->num_links + card->num_aux_devs),
+				 card->num_aux_devs,
 				 GFP_KERNEL);
-	if (card->rtd == NULL)
+	if (card->rtd_aux == NULL)
 		return -ENOMEM;
-	card->num_rtd = 0;
-	card->rtd_aux = &card->rtd[card->num_links];
-
-	for (i = 0; i < card->num_links; i++) {
-		card->rtd[i].card = card;
-		card->rtd[i].dai_link = &card->dai_link[i];
-		card->rtd[i].codec_dais = devm_kzalloc(card->dev,
-					sizeof(struct snd_soc_dai *) *
-					(card->rtd[i].dai_link->num_codecs),
-					GFP_KERNEL);
-		if (card->rtd[i].codec_dais == NULL)
-			return -ENOMEM;
-	}
 
 	for (i = 0; i < card->num_aux_devs; i++)
 		card->rtd_aux[i].card = card;
@@ -2442,8 +2488,7 @@ int snd_soc_register_card(struct snd_soc_card *card)
 		return ret;
 
 	/* deactivate pins to sleep state */
-	for (i = 0; i < card->num_rtd; i++) {
-		struct snd_soc_pcm_runtime *rtd = &card->rtd[i];
+	list_for_each_entry(rtd, &card->rtd_list, list)  {
 		struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 		int j;