sound/soc/generic/simple-card-utils.c - arm/linux - Git at Google

 /*
  * simple-card-utils.c
  *
  * Copyright (c) 2016 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
 #include <linux/clk.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_graph.h>
 #include <sound/simple_card_utils.h>

 void asoc_simple_card_convert_fixup(struct asoc_simple_card_data *data,
 				    struct snd_pcm_hw_params *params)
 {
 	struct snd_interval *rate = hw_param_interval(params,
 						SNDRV_PCM_HW_PARAM_RATE);
 	struct snd_interval *channels = hw_param_interval(params,
 						SNDRV_PCM_HW_PARAM_CHANNELS);

 	if (data->convert_rate)
 		rate->min =
 		rate->max = data->convert_rate;

 	if (data->convert_channels)
 		channels->min =
 		channels->max = data->convert_channels;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_convert_fixup);

 void asoc_simple_card_parse_convert(struct device *dev, char *prefix,
 				    struct asoc_simple_card_data *data)
 {
 	struct device_node *np = dev->of_node;
 	char prop[128];

 	if (!prefix)
 		prefix = "";

 	/* sampling rate convert */
 	snprintf(prop, sizeof(prop), "%s%s", prefix, "convert-rate");
 	of_property_read_u32(np, prop, &data->convert_rate);

 	/* channels transfer */
 	snprintf(prop, sizeof(prop), "%s%s", prefix, "convert-channels");
 	of_property_read_u32(np, prop, &data->convert_channels);

 	dev_dbg(dev, "convert_rate     %d\n", data->convert_rate);
 	dev_dbg(dev, "convert_channels %d\n", data->convert_channels);
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_convert);

 int asoc_simple_card_parse_daifmt(struct device *dev,
 				  struct device_node *node,
 				  struct device_node *codec,
 				  char *prefix,
 				  unsigned int *retfmt)
 {
 	struct device_node *bitclkmaster = NULL;
 	struct device_node *framemaster = NULL;
 	unsigned int daifmt;

 	daifmt = snd_soc_of_parse_daifmt(node, prefix,
 					 &bitclkmaster, &framemaster);
 	daifmt &= ~SND_SOC_DAIFMT_MASTER_MASK;

 	if (!bitclkmaster && !framemaster) {
 		/*
 		 * No dai-link level and master setting was not found from
 		 * sound node level, revert back to legacy DT parsing and
 		 * take the settings from codec node.
 		 */
 		dev_dbg(dev, "Revert to legacy daifmt parsing\n");

 		daifmt = snd_soc_of_parse_daifmt(codec, NULL, NULL, NULL) |
 			(daifmt & ~SND_SOC_DAIFMT_CLOCK_MASK);
 	} else {
 		if (codec == bitclkmaster)
 			daifmt |= (codec == framemaster) ?
 				SND_SOC_DAIFMT_CBM_CFM : SND_SOC_DAIFMT_CBM_CFS;
 		else
 			daifmt |= (codec == framemaster) ?
 				SND_SOC_DAIFMT_CBS_CFM : SND_SOC_DAIFMT_CBS_CFS;
 	}

 	of_node_put(bitclkmaster);
 	of_node_put(framemaster);

 	*retfmt = daifmt;

 	dev_dbg(dev, "format : %04x\n", daifmt);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_daifmt);

 int asoc_simple_card_set_dailink_name(struct device *dev,
 				      struct snd_soc_dai_link *dai_link,
 				      const char *fmt, ...)
 {
 	va_list ap;
 	char *name = NULL;
 	int ret = -ENOMEM;

 	va_start(ap, fmt);
 	name = devm_kvasprintf(dev, GFP_KERNEL, fmt, ap);
 	va_end(ap);

 	if (name) {
 		ret = 0;

 		dai_link->name		= name;
 		dai_link->stream_name	= name;

 		dev_dbg(dev, "name : %s\n", name);
 	}

 	return ret;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_set_dailink_name);

 int asoc_simple_card_parse_card_name(struct snd_soc_card *card,
 				     char *prefix)
 {
 	int ret;

 	if (!prefix)
 		prefix = "";

 	/* Parse the card name from DT */
 	ret = snd_soc_of_parse_card_name(card, "label");
 	if (ret < 0 || !card->name) {
 		char prop[128];

 		snprintf(prop, sizeof(prop), "%sname", prefix);
 		ret = snd_soc_of_parse_card_name(card, prop);
 		if (ret < 0)
 			return ret;
 	}

 	if (!card->name && card->dai_link)
 		card->name = card->dai_link->name;

 	dev_dbg(card->dev, "Card Name: %s\n", card->name ? card->name : "");

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_card_name);

 static void asoc_simple_card_clk_register(struct asoc_simple_dai *dai,
 					  struct clk *clk)
 {
 	dai->clk = clk;
 }

 int asoc_simple_card_clk_enable(struct asoc_simple_dai *dai)
 {
 	return clk_prepare_enable(dai->clk);
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_clk_enable);

 void asoc_simple_card_clk_disable(struct asoc_simple_dai *dai)
 {
 	clk_disable_unprepare(dai->clk);
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_clk_disable);

 int asoc_simple_card_parse_clk(struct device *dev,
 			       struct device_node *node,
 			       struct device_node *dai_of_node,
 			       struct asoc_simple_dai *simple_dai,
 			       const char *name)
 {
 	struct clk *clk;
 	u32 val;

 	/*
 	 * Parse dai->sysclk come from "clocks = <&xxx>"
 	 * (if system has common clock)
 	 *  or "system-clock-frequency = <xxx>"
 	 *  or device's module clock.
 	 */
 	clk = devm_get_clk_from_child(dev, node, NULL);
 	if (!IS_ERR(clk)) {
 		simple_dai->sysclk = clk_get_rate(clk);

 		asoc_simple_card_clk_register(simple_dai, clk);
 	} else if (!of_property_read_u32(node, "system-clock-frequency", &val)) {
 		simple_dai->sysclk = val;
 	} else {
 		clk = devm_get_clk_from_child(dev, dai_of_node, NULL);
 		if (!IS_ERR(clk))
 			simple_dai->sysclk = clk_get_rate(clk);
 	}

 	if (of_property_read_bool(node, "system-clock-direction-out"))
 		simple_dai->clk_direction = SND_SOC_CLOCK_OUT;

 	dev_dbg(dev, "%s : sysclk = %d, direction %d\n", name,
 		simple_dai->sysclk, simple_dai->clk_direction);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_clk);

 int asoc_simple_card_parse_dai(struct device_node *node,
 				    struct device_node **dai_of_node,
 				    const char **dai_name,
 				    const char *list_name,
 				    const char *cells_name,
 				    int *is_single_link)
 {
 	struct of_phandle_args args;
 	int ret;

 	if (!node)
 		return 0;

 	/*
 	 * Get node via "sound-dai = <&phandle port>"
 	 * it will be used as xxx_of_node on soc_bind_dai_link()
 	 */
 	ret = of_parse_phandle_with_args(node, list_name, cells_name, 0, &args);
 	if (ret)
 		return ret;

 	/* Get dai->name */
 	if (dai_name) {
 		ret = snd_soc_of_get_dai_name(node, dai_name);
 		if (ret < 0)
 			return ret;
 	}

 	*dai_of_node = args.np;

 	if (is_single_link)
 		*is_single_link = !args.args_count;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_dai);

 static int asoc_simple_card_get_dai_id(struct device_node *ep)
 {
 	struct device_node *node;
 	struct device_node *endpoint;
 	int i, id;
 	int ret;

 	ret = snd_soc_get_dai_id(ep);
 	if (ret != -ENOTSUPP)
 		return ret;

 	node = of_graph_get_port_parent(ep);

 	/*
 	 * Non HDMI sound case, counting port/endpoint on its DT
 	 * is enough. Let's count it.
 	 */
 	i = 0;
 	id = -1;
 	for_each_endpoint_of_node(node, endpoint) {
 		if (endpoint == ep)
 			id = i;
 		i++;
 	}

 	of_node_put(node);

 	if (id < 0)
 		return -ENODEV;

 	return id;
 }

 int asoc_simple_card_parse_graph_dai(struct device_node *ep,
 				     struct device_node **dai_of_node,
 				     const char **dai_name)
 {
 	struct device_node *node;
 	struct of_phandle_args args;
 	int ret;

 	if (!ep)
 		return 0;
 	if (!dai_name)
 		return 0;

 	node = of_graph_get_port_parent(ep);

 	/* Get dai->name */
 	args.np		= node;
 	args.args[0]	= asoc_simple_card_get_dai_id(ep);
 	args.args_count	= (of_graph_get_endpoint_count(node) > 1);

 	ret = snd_soc_get_dai_name(&args, dai_name);
 	if (ret < 0)
 		return ret;

 	*dai_of_node = node;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_parse_graph_dai);

 int asoc_simple_card_init_dai(struct snd_soc_dai *dai,
 			      struct asoc_simple_dai *simple_dai)
 {
 	int ret;

 	if (simple_dai->sysclk) {
 		ret = snd_soc_dai_set_sysclk(dai, 0, simple_dai->sysclk,
 					     simple_dai->clk_direction);
 		if (ret && ret != -ENOTSUPP) {
 			dev_err(dai->dev, "simple-card: set_sysclk error\n");
 			return ret;
 		}
 	}

 	if (simple_dai->slots) {
 		ret = snd_soc_dai_set_tdm_slot(dai,
 					       simple_dai->tx_slot_mask,
 					       simple_dai->rx_slot_mask,
 					       simple_dai->slots,
 					       simple_dai->slot_width);
 		if (ret && ret != -ENOTSUPP) {
 			dev_err(dai->dev, "simple-card: set_tdm_slot error\n");
 			return ret;
 		}
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_init_dai);

 int asoc_simple_card_canonicalize_dailink(struct snd_soc_dai_link *dai_link)
 {
 	/* Assumes platform == cpu */
 	if (!dai_link->platform_of_node)
 		dai_link->platform_of_node = dai_link->cpu_of_node;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_canonicalize_dailink);

 void asoc_simple_card_canonicalize_cpu(struct snd_soc_dai_link *dai_link,
 				       int is_single_links)
 {
 	/*
 	 * In soc_bind_dai_link() will check cpu name after
 	 * of_node matching if dai_link has cpu_dai_name.
 	 * but, it will never match if name was created by
 	 * fmt_single_name() remove cpu_dai_name if cpu_args
 	 * was 0. See:
 	 *	fmt_single_name()
 	 *	fmt_multiple_name()
 	 */
 	if (is_single_links)
 		dai_link->cpu_dai_name = NULL;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_canonicalize_cpu);

 int asoc_simple_card_clean_reference(struct snd_soc_card *card)
 {
 	struct snd_soc_dai_link *dai_link;
 	int num_links;

 	for (num_links = 0, dai_link = card->dai_link;
 	     num_links < card->num_links;
 	     num_links++, dai_link++) {
 		of_node_put(dai_link->cpu_of_node);
 		of_node_put(dai_link->codec_of_node);
 	}
 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_clean_reference);

 int asoc_simple_card_of_parse_routing(struct snd_soc_card *card,
 				      char *prefix,
 				      int optional)
 {
 	struct device_node *node = card->dev->of_node;
 	char prop[128];

 	if (!prefix)
 		prefix = "";

 	snprintf(prop, sizeof(prop), "%s%s", prefix, "routing");

 	if (!of_property_read_bool(node, prop)) {
 		if (optional)
 			return 0;
 		return -EINVAL;
 	}

 	return snd_soc_of_parse_audio_routing(card, prop);
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_of_parse_routing);

 int asoc_simple_card_of_parse_widgets(struct snd_soc_card *card,
 				      char *prefix)
 {
 	struct device_node *node = card->dev->of_node;
 	char prop[128];

 	if (!prefix)
 		prefix = "";

 	snprintf(prop, sizeof(prop), "%s%s", prefix, "widgets");

 	if (of_property_read_bool(node, prop))
 		return snd_soc_of_parse_audio_simple_widgets(card, prop);

 	/* no widgets is not error */
 	return 0;
 }
 EXPORT_SYMBOL_GPL(asoc_simple_card_of_parse_widgets);

 /* Module information */
 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 MODULE_DESCRIPTION("ALSA SoC Simple Card Utils");
 MODULE_LICENSE("GPL v2");
	/*
	* simple-card-utils.c
	*
	* Copyright (c) 2016 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/
	#include <linux/clk.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_graph.h>
	#include <sound/simple_card_utils.h>

	void asoc_simple_card_convert_fixup(struct asoc_simple_card_data *data,
	struct snd_pcm_hw_params *params)
	{
	struct snd_interval *rate = hw_param_interval(params,
	SNDRV_PCM_HW_PARAM_RATE);
	struct snd_interval *channels = hw_param_interval(params,
	SNDRV_PCM_HW_PARAM_CHANNELS);

	if (data->convert_rate)
	rate->min =
	rate->max = data->convert_rate;

	if (data->convert_channels)
	channels->min =
	channels->max = data->convert_channels;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_convert_fixup);

	void asoc_simple_card_parse_convert(struct device dev, char prefix,
	struct asoc_simple_card_data *data)
	{
	struct device_node *np = dev->of_node;
	char prop[128];

	if (!prefix)
	prefix = "";

	/* sampling rate convert */
	snprintf(prop, sizeof(prop), "%s%s", prefix, "convert-rate");
	of_property_read_u32(np, prop, &data->convert_rate);

	/* channels transfer */
	snprintf(prop, sizeof(prop), "%s%s", prefix, "convert-channels");
	of_property_read_u32(np, prop, &data->convert_channels);

	dev_dbg(dev, "convert_rate %d\n", data->convert_rate);
	dev_dbg(dev, "convert_channels %d\n", data->convert_channels);
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_convert);

	int asoc_simple_card_parse_daifmt(struct device *dev,
	struct device_node *node,
	struct device_node *codec,
	char *prefix,
	unsigned int *retfmt)
	{
	struct device_node *bitclkmaster = NULL;
	struct device_node *framemaster = NULL;
	unsigned int daifmt;

	daifmt = snd_soc_of_parse_daifmt(node, prefix,
	&bitclkmaster, &framemaster);
	daifmt &= ~SND_SOC_DAIFMT_MASTER_MASK;

	if (!bitclkmaster && !framemaster) {
	/*
	* No dai-link level and master setting was not found from
	* sound node level, revert back to legacy DT parsing and
	* take the settings from codec node.
	*/
	dev_dbg(dev, "Revert to legacy daifmt parsing\n");

	daifmt = snd_soc_of_parse_daifmt(codec, NULL, NULL, NULL) \|
	(daifmt & ~SND_SOC_DAIFMT_CLOCK_MASK);
	} else {
	if (codec == bitclkmaster)
	daifmt \|= (codec == framemaster) ?
	SND_SOC_DAIFMT_CBM_CFM : SND_SOC_DAIFMT_CBM_CFS;
	else
	daifmt \|= (codec == framemaster) ?
	SND_SOC_DAIFMT_CBS_CFM : SND_SOC_DAIFMT_CBS_CFS;
	}

	of_node_put(bitclkmaster);
	of_node_put(framemaster);

	*retfmt = daifmt;

	dev_dbg(dev, "format : %04x\n", daifmt);

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_daifmt);

	int asoc_simple_card_set_dailink_name(struct device *dev,
	struct snd_soc_dai_link *dai_link,
	const char *fmt, ...)
	{
	va_list ap;
	char *name = NULL;
	int ret = -ENOMEM;

	va_start(ap, fmt);
	name = devm_kvasprintf(dev, GFP_KERNEL, fmt, ap);
	va_end(ap);

	if (name) {
	ret = 0;

	dai_link->name = name;
	dai_link->stream_name = name;

	dev_dbg(dev, "name : %s\n", name);
	}

	return ret;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_set_dailink_name);

	int asoc_simple_card_parse_card_name(struct snd_soc_card *card,
	char *prefix)
	{
	int ret;

	if (!prefix)
	prefix = "";

	/* Parse the card name from DT */
	ret = snd_soc_of_parse_card_name(card, "label");
	if (ret < 0 \|\| !card->name) {
	char prop[128];

	snprintf(prop, sizeof(prop), "%sname", prefix);
	ret = snd_soc_of_parse_card_name(card, prop);
	if (ret < 0)
	return ret;
	}

	if (!card->name && card->dai_link)
	card->name = card->dai_link->name;

	dev_dbg(card->dev, "Card Name: %s\n", card->name ? card->name : "");

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_card_name);

	static void asoc_simple_card_clk_register(struct asoc_simple_dai *dai,
	struct clk *clk)
	{
	dai->clk = clk;
	}

	int asoc_simple_card_clk_enable(struct asoc_simple_dai *dai)
	{
	return clk_prepare_enable(dai->clk);
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_clk_enable);

	void asoc_simple_card_clk_disable(struct asoc_simple_dai *dai)
	{
	clk_disable_unprepare(dai->clk);
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_clk_disable);

	int asoc_simple_card_parse_clk(struct device *dev,
	struct device_node *node,
	struct device_node *dai_of_node,
	struct asoc_simple_dai *simple_dai,
	const char *name)
	{
	struct clk *clk;
	u32 val;

	/*
	* Parse dai->sysclk come from "clocks = <&xxx>"
	* (if system has common clock)
	* or "system-clock-frequency = <xxx>"
	* or device's module clock.
	*/
	clk = devm_get_clk_from_child(dev, node, NULL);
	if (!IS_ERR(clk)) {
	simple_dai->sysclk = clk_get_rate(clk);

	asoc_simple_card_clk_register(simple_dai, clk);
	} else if (!of_property_read_u32(node, "system-clock-frequency", &val)) {
	simple_dai->sysclk = val;
	} else {
	clk = devm_get_clk_from_child(dev, dai_of_node, NULL);
	if (!IS_ERR(clk))
	simple_dai->sysclk = clk_get_rate(clk);
	}

	if (of_property_read_bool(node, "system-clock-direction-out"))
	simple_dai->clk_direction = SND_SOC_CLOCK_OUT;

	dev_dbg(dev, "%s : sysclk = %d, direction %d\n", name,
	simple_dai->sysclk, simple_dai->clk_direction);

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_clk);

	int asoc_simple_card_parse_dai(struct device_node *node,
	struct device_node **dai_of_node,
	const char **dai_name,
	const char *list_name,
	const char *cells_name,
	int *is_single_link)
	{
	struct of_phandle_args args;
	int ret;

	if (!node)
	return 0;

	/*
	* Get node via "sound-dai = <&phandle port>"
	* it will be used as xxx_of_node on soc_bind_dai_link()
	*/
	ret = of_parse_phandle_with_args(node, list_name, cells_name, 0, &args);
	if (ret)
	return ret;

	/* Get dai->name */
	if (dai_name) {
	ret = snd_soc_of_get_dai_name(node, dai_name);
	if (ret < 0)
	return ret;
	}

	*dai_of_node = args.np;

	if (is_single_link)
	*is_single_link = !args.args_count;

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_dai);

	static int asoc_simple_card_get_dai_id(struct device_node *ep)
	{
	struct device_node *node;
	struct device_node *endpoint;
	int i, id;
	int ret;

	ret = snd_soc_get_dai_id(ep);
	if (ret != -ENOTSUPP)
	return ret;

	node = of_graph_get_port_parent(ep);

	/*
	* Non HDMI sound case, counting port/endpoint on its DT
	* is enough. Let's count it.
	*/
	i = 0;
	id = -1;
	for_each_endpoint_of_node(node, endpoint) {
	if (endpoint == ep)
	id = i;
	i++;
	}

	of_node_put(node);

	if (id < 0)
	return -ENODEV;

	return id;
	}

	int asoc_simple_card_parse_graph_dai(struct device_node *ep,
	struct device_node **dai_of_node,
	const char **dai_name)
	{
	struct device_node *node;
	struct of_phandle_args args;
	int ret;

	if (!ep)
	return 0;
	if (!dai_name)
	return 0;

	node = of_graph_get_port_parent(ep);

	/* Get dai->name */
	args.np = node;
	args.args[0] = asoc_simple_card_get_dai_id(ep);
	args.args_count = (of_graph_get_endpoint_count(node) > 1);

	ret = snd_soc_get_dai_name(&args, dai_name);
	if (ret < 0)
	return ret;

	*dai_of_node = node;

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_parse_graph_dai);

	int asoc_simple_card_init_dai(struct snd_soc_dai *dai,
	struct asoc_simple_dai *simple_dai)
	{
	int ret;

	if (simple_dai->sysclk) {
	ret = snd_soc_dai_set_sysclk(dai, 0, simple_dai->sysclk,
	simple_dai->clk_direction);
	if (ret && ret != -ENOTSUPP) {
	dev_err(dai->dev, "simple-card: set_sysclk error\n");
	return ret;
	}
	}

	if (simple_dai->slots) {
	ret = snd_soc_dai_set_tdm_slot(dai,
	simple_dai->tx_slot_mask,
	simple_dai->rx_slot_mask,
	simple_dai->slots,
	simple_dai->slot_width);
	if (ret && ret != -ENOTSUPP) {
	dev_err(dai->dev, "simple-card: set_tdm_slot error\n");
	return ret;
	}
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_init_dai);

	int asoc_simple_card_canonicalize_dailink(struct snd_soc_dai_link *dai_link)
	{
	/* Assumes platform == cpu */
	if (!dai_link->platform_of_node)
	dai_link->platform_of_node = dai_link->cpu_of_node;

	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_canonicalize_dailink);

	void asoc_simple_card_canonicalize_cpu(struct snd_soc_dai_link *dai_link,
	int is_single_links)
	{
	/*
	* In soc_bind_dai_link() will check cpu name after
	* of_node matching if dai_link has cpu_dai_name.
	* but, it will never match if name was created by
	* fmt_single_name() remove cpu_dai_name if cpu_args
	* was 0. See:
	* fmt_single_name()
	* fmt_multiple_name()
	*/
	if (is_single_links)
	dai_link->cpu_dai_name = NULL;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_canonicalize_cpu);

	int asoc_simple_card_clean_reference(struct snd_soc_card *card)
	{
	struct snd_soc_dai_link *dai_link;
	int num_links;

	for (num_links = 0, dai_link = card->dai_link;
	num_links < card->num_links;
	num_links++, dai_link++) {
	of_node_put(dai_link->cpu_of_node);
	of_node_put(dai_link->codec_of_node);
	}
	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_clean_reference);

	int asoc_simple_card_of_parse_routing(struct snd_soc_card *card,
	char *prefix,
	int optional)
	{
	struct device_node *node = card->dev->of_node;
	char prop[128];

	if (!prefix)
	prefix = "";

	snprintf(prop, sizeof(prop), "%s%s", prefix, "routing");

	if (!of_property_read_bool(node, prop)) {
	if (optional)
	return 0;
	return -EINVAL;
	}

	return snd_soc_of_parse_audio_routing(card, prop);
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_of_parse_routing);

	int asoc_simple_card_of_parse_widgets(struct snd_soc_card *card,
	char *prefix)
	{
	struct device_node *node = card->dev->of_node;
	char prop[128];

	if (!prefix)
	prefix = "";

	snprintf(prop, sizeof(prop), "%s%s", prefix, "widgets");

	if (of_property_read_bool(node, prop))
	return snd_soc_of_parse_audio_simple_widgets(card, prop);

	/* no widgets is not error */
	return 0;
	}
	EXPORT_SYMBOL_GPL(asoc_simple_card_of_parse_widgets);

	/* Module information */
	MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
	MODULE_DESCRIPTION("ALSA SoC Simple Card Utils");
	MODULE_LICENSE("GPL v2");