[PATCH v2 05/14] ASoC: audio-graph-card2: add Audio Graph Card2 driver

Kuninori Morimoto kuninori.morimoto.gx at renesas.com
Tue Jul 20 03:40:09 CEST 2021


From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>

We already have audio-graph-card which is Of-graph base of general
sound card driver.

It is also supporting DPCM connection, but was forcibly expanded.
Thus, it is very difficult to add new features on it, for example
Multi CPU/Codec support, Codec2Codec support, etc.

This patch adds more flexible new Audio Graph Card2 driver for it.
audio-graph-card and audio-graph-card2 are similar, but don't have
full compatibility.

Difference between audio-graph-card and audio-graph-card2 are

	- audio-graph-card  used "dais"  to indicate DAI-links,
	  audio-graph-card2 uses "links" to it.

	- audio-graph-card  used "phandle" to indicate bitclock/frame-master,
	  audio-graph-card2 uses flag to it.

	- audio-graph-card  used "format" to indicate DAI format,
	  audio-graph-card2 assumes CPU/Codec drivers have .get_fmt support.

Audio Graph Card2 supports very generic connection, but some users
want to have its own settings, for example PLL settings, etc.
For such case, it has customizing support.
In users own driver, it can use Audio Graph Card2 parsing by using
asoc_graph_parse_of2(), and doing its own customizing.

Because Audio Graph Card2 is still under experimental stage,
it will indicate such warning when probing, and the DT syntax
might be changed.

Link: https://lore.kernel.org/r/87k0xszlep.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
 include/sound/graph_card.h            |  15 +
 sound/soc/generic/Kconfig             |   8 +
 sound/soc/generic/Makefile            |   2 +
 sound/soc/generic/audio-graph-card2.c | 659 ++++++++++++++++++++++++++
 4 files changed, 684 insertions(+)
 create mode 100644 sound/soc/generic/audio-graph-card2.c

diff --git a/include/sound/graph_card.h b/include/sound/graph_card.h
index 6f10bfb0d5ee..b3185783caa7 100644
--- a/include/sound/graph_card.h
+++ b/include/sound/graph_card.h
@@ -9,6 +9,21 @@
 
 #include <sound/simple_card_utils.h>
 
+typedef int (*GRAPH_CUSTOM)(struct asoc_simple_priv *priv,
+			    struct device_node *lnk,
+			    struct link_info *li);
+
+struct graph_custom_hooks {
+	int (*hook_pre)(struct asoc_simple_priv *priv);
+	int (*hook_post)(struct asoc_simple_priv *priv);
+	GRAPH_CUSTOM custom_normal;
+};
+
 int audio_graph_parse_of(struct asoc_simple_priv *priv, struct device *dev);
+int audio_graph2_parse_of(struct asoc_simple_priv *priv, struct device *dev,
+			  struct graph_custom_hooks *hooks);
+
+int audio_graph2_link_normal(struct asoc_simple_priv *priv,
+			     struct device_node *lnk, struct link_info *li);
 
 #endif /* __GRAPH_CARD_H */
diff --git a/sound/soc/generic/Kconfig b/sound/soc/generic/Kconfig
index bb734780669e..3385c488cd85 100644
--- a/sound/soc/generic/Kconfig
+++ b/sound/soc/generic/Kconfig
@@ -18,6 +18,14 @@ config SND_AUDIO_GRAPH_CARD
 	  with OF-graph DT bindings.
 	  It also support DPCM of multi CPU single Codec ststem.
 
+config SND_AUDIO_GRAPH_CARD2
+	tristate "ASoC Audio Graph Sound Card2 support"
+	depends on OF
+	select SND_SIMPLE_CARD_UTILS
+	help
+	  This option enables generic simple sound card support
+	  with OF-graph DT bindings.
+
 config SND_TEST_COMPONENT
 	tristate "ASoC Test component sound support"
 	depends on OF
diff --git a/sound/soc/generic/Makefile b/sound/soc/generic/Makefile
index 988bfd45d2e2..b480f47a330d 100644
--- a/sound/soc/generic/Makefile
+++ b/sound/soc/generic/Makefile
@@ -2,9 +2,11 @@
 snd-soc-simple-card-utils-objs	:= simple-card-utils.o
 snd-soc-simple-card-objs	:= simple-card.o
 snd-soc-audio-graph-card-objs	:= audio-graph-card.o
+snd-soc-audio-graph-card2-objs	:= audio-graph-card2.o
 snd-soc-test-component-objs	:= test-component.o
 
 obj-$(CONFIG_SND_SIMPLE_CARD_UTILS)	+= snd-soc-simple-card-utils.o
 obj-$(CONFIG_SND_SIMPLE_CARD)		+= snd-soc-simple-card.o
 obj-$(CONFIG_SND_AUDIO_GRAPH_CARD)	+= snd-soc-audio-graph-card.o
+obj-$(CONFIG_SND_AUDIO_GRAPH_CARD2)	+= snd-soc-audio-graph-card2.o
 obj-$(CONFIG_SND_TEST_COMPONENT)	+= snd-soc-test-component.o
diff --git a/sound/soc/generic/audio-graph-card2.c b/sound/soc/generic/audio-graph-card2.c
new file mode 100644
index 000000000000..f5edf1368e12
--- /dev/null
+++ b/sound/soc/generic/audio-graph-card2.c
@@ -0,0 +1,659 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// ASoC Audio Graph Sound Card2 support
+//
+// Copyright (C) 2020 Renesas Solutions Corp.
+// Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
+//
+// based on ${LINUX}/sound/soc/generic/audio-graph-card.c
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <linux/string.h>
+#include <sound/graph_card.h>
+
+/************************************
+	daifmt
+ ************************************
+	ports {
+		format = "left_j";
+		port at 0 {
+			bitclock-master;
+			sample0: endpoint at 0 {
+				frame-master;
+			};
+			sample1: endpoint at 1 {
+				format = "i2s";
+			};
+		};
+		...
+	};
+
+ You can set daifmt at ports/port/endpoint.
+ It uses *latest* format, and *share* master settings.
+ In above case,
+	sample0: left_j, bitclock-master, frame-master
+	sample1: i2s,    bitclock-master
+
+ NOTE is that card2 is assuming to use .get_fmt.
+
+ If there was no settings, *Codec* will be
+ bitclock/frame master as default.
+ see
+	graph_parse_daifmt().
+
+ ************************************
+	Normal Audio-Graph
+ ************************************
+
+ CPU <---> Codec
+
+ sound {
+	compatible = "audio-graph-card2";
+	links = <&cpu>;
+ };
+
+ CPU {
+	cpu: port {
+		bitclock-master;
+		frame-master;
+		cpu_ep: endpoint { remote-endpoint = <&codec_ep>; }; };
+ };
+
+ Codec {
+	port {	codec_ep: endpoint { remote-endpoint = <&cpu_ep>; }; };
+ };
+
+*/
+
+enum graph_type {
+	GRAPH_NORMAL,
+};
+
+#define port_to_endpoint(port) of_get_child_by_name(port, "endpoint")
+
+static enum graph_type graph_get_type(struct asoc_simple_priv *priv,
+				      struct device_node *link)
+{
+	struct device_node *top;
+	const char *string;
+	enum graph_type type = GRAPH_NORMAL;
+	int ret;
+
+	/* link is port or ports */
+	top = of_get_parent(link);
+	if (of_node_name_eq(top, "ports")) {
+		of_node_put(top);
+		top = of_get_parent(top);
+	}
+
+	ret = of_property_read_string(top, "compatible", &string);
+	if (ret < 0)
+		goto end;
+
+end:
+#ifdef DEBUG
+	{
+		const char *str = "Normal";
+
+		dev_dbg(dev, "%pOF (%s)", link, str);
+	}
+#endif
+	of_node_put(top);
+
+	return type;
+}
+
+static const struct snd_soc_ops graph_ops = {
+	.startup	= asoc_simple_startup,
+	.shutdown	= asoc_simple_shutdown,
+	.hw_params	= asoc_simple_hw_params,
+};
+
+static int graph_get_dai_id(struct device_node *ep)
+{
+	struct device_node *node;
+	struct device_node *endpoint;
+	struct of_endpoint info;
+	int i, id;
+	const u32 *reg;
+	int ret;
+
+	/* use driver specified DAI ID if exist */
+	ret = snd_soc_get_dai_id(ep);
+	if (ret != -ENOTSUPP)
+		return ret;
+
+	/* use endpoint/port reg if exist */
+	ret = of_graph_parse_endpoint(ep, &info);
+	if (ret == 0) {
+		/*
+		 * Because it will count port/endpoint if it doesn't have "reg".
+		 * But, we can't judge whether it has "no reg", or "reg = <0>"
+		 * only of_graph_parse_endpoint().
+		 * We need to check "reg" property
+		 */
+		if (of_get_property(ep,   "reg", NULL))
+			return info.id;
+
+		node = of_get_parent(ep);
+		reg = of_get_property(node, "reg", NULL);
+		of_node_put(node);
+		if (reg)
+			return info.port;
+	}
+	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;
+}
+
+static int asoc_simple_parse_dai(struct device_node *ep,
+				 struct snd_soc_dai_link_component *dlc,
+				 int *is_single_link)
+{
+	struct device_node *node;
+	struct of_phandle_args args;
+	int ret;
+
+	if (!ep)
+		return 0;
+
+	node = of_graph_get_port_parent(ep);
+
+	/* Get dai->name */
+	args.np		= node;
+	args.args[0]	= graph_get_dai_id(ep);
+	args.args_count	= (of_graph_get_endpoint_count(node) > 1);
+
+	/*
+	 * FIXME
+	 *
+	 * Here, dlc->dai_name is pointer to CPU/Codec DAI name.
+	 * If user unbinded CPU or Codec driver, but not for Sound Card,
+	 * dlc->dai_name is keeping unbinded CPU or Codec
+	 * driver's pointer.
+	 *
+	 * If user re-bind CPU or Codec driver again, ALSA SoC will try
+	 * to rebind Card via snd_soc_try_rebind_card(), but because of
+	 * above reason, it might can't bind Sound Card.
+	 * Because Sound Card is pointing to released dai_name pointer.
+	 *
+	 * To avoid this rebind Card issue,
+	 * 1) It needs to alloc memory to keep dai_name eventhough
+	 *    CPU or Codec driver was unbinded, or
+	 * 2) user need to rebind Sound Card everytime
+	 *    if he unbinded CPU or Codec.
+	 */
+	ret = snd_soc_get_dai_name(&args, &dlc->dai_name);
+	if (ret < 0)
+		return ret;
+
+	dlc->of_node = node;
+
+	if (is_single_link)
+		*is_single_link = of_graph_get_endpoint_count(node) == 1;
+
+	return 0;
+}
+
+static void graph_parse_mclk_fs(struct device_node *ep,
+				struct simple_dai_props *props)
+{
+	struct device_node *port	= of_get_parent(ep);
+	struct device_node *ports	= of_get_parent(port);
+
+	if (of_node_name_eq(ports, "ports"))
+		of_property_read_u32(ports, "mclk-fs", &props->mclk_fs);
+	of_property_read_u32(port,	"mclk-fs", &props->mclk_fs);
+	of_property_read_u32(ep,	"mclk-fs", &props->mclk_fs);
+
+	of_node_put(port);
+	of_node_put(ports);
+}
+
+static int graph_dai_init(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_dai *dai;
+	struct device *dev = rtd->dev;
+	int i;
+
+	/*
+	 * Indicate assumption for a while.
+	 * It will be removed.
+	 */
+	for_each_rtd_dais(rtd, i, dai)
+		if (!dai->driver->ops ||
+		    !dai->driver->ops->auto_selectable_formats) {
+			dev_warn_once(dev, "audio-graph-card2 is assuming "
+				"DAI driver (%s) has .auto_selectable_formats\n", dai->name);
+			break;
+		}
+
+	return asoc_simple_dai_init(rtd);
+}
+
+static int graph_parse_node(struct asoc_simple_priv *priv,
+			    struct device_node *ep,
+			    struct link_info *li,
+			    int idx, int *cpu)
+{
+	struct device *dev = simple_priv_to_dev(priv);
+	struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
+	struct simple_dai_props *dai_props = simple_priv_to_props(priv, li->link);
+	struct snd_soc_dai_link_component *dlc;
+	struct asoc_simple_dai *dai;
+	int ret;
+
+	if (cpu) {
+		dlc = asoc_link_to_cpu(dai_link, idx);
+		dai = simple_props_to_dai_cpu(dai_props, idx);
+	} else {
+		dlc = asoc_link_to_codec(dai_link, idx);
+		dai = simple_props_to_dai_codec(dai_props, idx);
+	}
+
+	graph_parse_mclk_fs(ep, dai_props);
+
+	ret = asoc_simple_parse_dai(ep, dlc, cpu);
+	if (ret < 0)
+		return ret;
+
+	ret = asoc_simple_parse_tdm(ep, dai);
+	if (ret < 0)
+		return ret;
+
+	ret = asoc_simple_parse_clk(dev, ep, dai, dlc);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void graph_parse_daifmt(struct device_node *node,
+			       unsigned int *daifmt, unsigned int *bit_frame)
+{
+	unsigned int fmt;
+
+	/*
+	 * see also above "daifmt" explanation
+	 * and samples.
+	 */
+
+	/*
+	 *	ports {
+	 * (A)
+	 *		port {
+	 * (B)
+	 *			endpoint {
+	 * (C)
+	 *			};
+	 *		};
+	 *	};
+	 * };
+	 */
+
+	/*
+	 * clock_provider:
+	 *
+	 * It can be judged it is provider
+	 * if (A) or (B) or (C) has bitclock-master / frame-master flag.
+	 *
+	 * use "or"
+	 */
+	*bit_frame |= snd_soc_daifmt_parse_clock_provider_as_bitmap(node, NULL);
+
+#define update_daifmt(name)					\
+	if (!(*daifmt & SND_SOC_DAIFMT_##name##_MASK) &&	\
+		 (fmt & SND_SOC_DAIFMT_##name##_MASK))		\
+		*daifmt |= fmt & SND_SOC_DAIFMT_##name##_MASK;
+
+	/*
+	 * format
+	 *
+	 * This function is called by (C) -> (B) -> (A) order.
+	 * Set if applicable part was not yet set.
+	 */
+	fmt = snd_soc_daifmt_parse_format(node, NULL);
+	update_daifmt(FORMAT);
+	update_daifmt(CLOCK);
+	update_daifmt(INV);
+}
+
+static int graph_link_init(struct asoc_simple_priv *priv,
+			   struct device_node *ep,
+			   struct link_info *li,
+			   int is_cpu_node,
+			   char *name)
+{
+	struct device *dev = simple_priv_to_dev(priv);
+	struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
+	struct device_node *port  = of_get_parent(ep);
+	struct device_node *ports = of_get_parent(port);
+	unsigned int daifmt = 0, daiclk = 0;
+	unsigned int bit_frame = 0;
+
+	/*
+	 *	ports {
+	 * (A)
+	 *		port {
+	 * (B)
+	 *			endpoint {
+	 * (C)
+	 *			};
+	 *		};
+	 *	};
+	 * };
+	 */
+	graph_parse_daifmt(ep,    &daifmt, &bit_frame);		/* (C) */
+	graph_parse_daifmt(port,  &daifmt, &bit_frame);		/* (B) */
+	if (of_node_name_eq(ports, "ports"))
+		graph_parse_daifmt(ports, &daifmt, &bit_frame);	/* (A) */
+
+	/*
+	 * convert bit_frame
+	 * We need to flip clock_provider if it was CPU node,
+	 * because it is Codec base.
+	 */
+	daiclk = snd_soc_daifmt_clock_provider_from_bitmap(bit_frame);
+	if (is_cpu_node)
+		daiclk = snd_soc_daifmt_clock_provider_fliped(daiclk);
+
+	if (daifmt)
+		dev_warn(dev, "don't use format. implemente .set_fmt instead (%pOFf)\n", port);
+
+	dai_link->dai_fmt	= daifmt | daiclk;
+	dai_link->init		= graph_dai_init;
+	dai_link->ops		= &graph_ops;
+	if (priv->ops)
+		dai_link->ops	= priv->ops;
+
+	return asoc_simple_set_dailink_name(dev, dai_link, name);
+}
+
+int audio_graph2_link_normal(struct asoc_simple_priv *priv,
+			     struct device_node *lnk,
+			     struct link_info *li)
+{
+	struct snd_soc_dai_link *dai_link = simple_priv_to_link(priv, li->link);
+	struct device_node *cpu_port = lnk;
+	struct device_node *cpu_ep = port_to_endpoint(cpu_port);
+	struct device_node *codec_ep = of_graph_get_remote_endpoint(cpu_ep);
+	struct snd_soc_dai_link_component *cpus = asoc_link_to_cpu(dai_link, 0);
+	struct snd_soc_dai_link_component *codecs = asoc_link_to_codec(dai_link, 0);
+	char dai_name[64];
+	int ret, is_single_links = 0;
+
+	ret = graph_parse_node(priv, cpu_ep, li, 0, &is_single_links);
+	if (ret < 0)
+		goto err;
+
+	ret = graph_parse_node(priv, codec_ep, li, 0, NULL);
+	if (ret < 0)
+		goto err;
+
+	snprintf(dai_name, sizeof(dai_name),
+		 "%s-%s", cpus->dai_name, codecs->dai_name);
+
+	asoc_simple_canonicalize_cpu(cpus, is_single_links);
+
+	ret = graph_link_init(priv, cpu_ep, li, 1, dai_name);
+	if (ret < 0)
+		goto err;
+
+err:
+	of_node_put(cpu_ep);
+	of_node_put(codec_ep);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(audio_graph2_link_normal);
+
+static int graph_link(struct asoc_simple_priv *priv,
+		      struct graph_custom_hooks *hooks,
+		      enum graph_type gtype,
+		      struct device_node *lnk,
+		      struct link_info *li)
+{
+	struct device *dev = simple_priv_to_dev(priv);
+	GRAPH_CUSTOM func = NULL;
+	int ret = -EINVAL;
+
+	switch (gtype) {
+	case GRAPH_NORMAL:
+		if (hooks && hooks->custom_normal)
+			func = hooks->custom_normal;
+		else
+			func = audio_graph2_link_normal;
+		break;
+	}
+
+	if (!func) {
+		dev_err(dev, "non supported gtype (%d)\n", gtype);
+		goto err;
+	}
+
+	ret = func(priv, lnk, li);
+	if (ret < 0)
+		goto err;
+
+	li->link++;
+err:
+	return ret;
+}
+
+static int graph_count_normal(struct asoc_simple_priv *priv,
+			      struct device_node *lnk,
+			      struct link_info *li)
+{
+	/*
+	 *	CPU {
+	 * =>		lnk: port { endpoint { .. }; };
+	 *	};
+	 */
+	li->num[li->link].cpus		= 1;
+	li->num[li->link].codecs	= 1;
+
+	return 0;
+}
+
+static int graph_count(struct asoc_simple_priv *priv,
+		       struct graph_custom_hooks *hooks,
+		       enum graph_type gtype,
+		       struct device_node *lnk,
+		       struct link_info *li)
+{
+	struct device *dev = simple_priv_to_dev(priv);
+	GRAPH_CUSTOM func = NULL;
+	int ret = -EINVAL;
+
+	if (li->link >= SNDRV_MAX_LINKS) {
+		dev_err(dev, "too many links\n");
+		return ret;
+	}
+
+	switch (gtype) {
+	case GRAPH_NORMAL:
+		func = graph_count_normal;
+		break;
+	}
+
+	if (!func) {
+		dev_err(dev, "non supported gtype (%d)\n", gtype);
+		goto err;
+	}
+
+	ret = func(priv, lnk, li);
+	if (ret < 0)
+		goto err;
+
+	li->link++;
+err:
+	return ret;
+}
+
+static int graph_for_each_link(struct asoc_simple_priv *priv,
+			       struct graph_custom_hooks *hooks,
+			       struct link_info *li,
+			       int (*func)(struct asoc_simple_priv *priv,
+					   struct graph_custom_hooks *hooks,
+					   enum graph_type gtype,
+					   struct device_node *lnk,
+					   struct link_info *li))
+{
+	struct of_phandle_iterator it;
+	struct device *dev = simple_priv_to_dev(priv);
+	struct device_node *node = dev->of_node;
+	struct device_node *lnk;
+	enum graph_type gtype;
+	int rc, ret;
+
+	/* loop for all listed CPU port */
+	of_for_each_phandle(&it, rc, node, "links", NULL, 0) {
+		lnk = it.node;
+
+		gtype = graph_get_type(priv, lnk);
+
+		ret = func(priv, hooks, gtype, lnk, li);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+int audio_graph2_parse_of(struct asoc_simple_priv *priv, struct device *dev,
+			  struct graph_custom_hooks *hooks)
+{
+	struct snd_soc_card *card = simple_priv_to_card(priv);
+	struct link_info *li;
+	int ret;
+
+	dev_warn(dev, "Audio Graph Card2 is still under Experimental stage\n");
+
+	li = devm_kzalloc(dev, sizeof(*li), GFP_KERNEL);
+	if (!li)
+		return -ENOMEM;
+
+	card->probe	= asoc_graph_card_probe;
+	card->owner	= THIS_MODULE;
+	card->dev	= dev;
+
+	if ((hooks) && (hooks)->hook_pre) {
+		ret = (hooks)->hook_pre(priv);
+		if (ret < 0)
+			goto err;
+	}
+
+	ret = graph_for_each_link(priv, hooks, li, graph_count);
+	if (!li->link)
+		ret = -EINVAL;
+	if (ret < 0)
+		goto err;
+
+	ret = asoc_simple_init_priv(priv, li);
+	if (ret < 0)
+		goto err;
+
+	priv->pa_gpio = devm_gpiod_get_optional(dev, "pa", GPIOD_OUT_LOW);
+	if (IS_ERR(priv->pa_gpio)) {
+		ret = PTR_ERR(priv->pa_gpio);
+		dev_err(dev, "failed to get amplifier gpio: %d\n", ret);
+		goto err;
+	}
+
+	ret = asoc_simple_parse_widgets(card, NULL);
+	if (ret < 0)
+		goto err;
+
+	ret = asoc_simple_parse_routing(card, NULL);
+	if (ret < 0)
+		goto err;
+
+	memset(li, 0, sizeof(*li));
+	ret = graph_for_each_link(priv, hooks, li, graph_link);
+	if (ret < 0)
+		goto err;
+
+	ret = asoc_simple_parse_card_name(card, NULL);
+	if (ret < 0)
+		goto err;
+
+	snd_soc_card_set_drvdata(card, priv);
+
+	if ((hooks) && (hooks)->hook_post) {
+		ret = (hooks)->hook_post(priv);
+		if (ret < 0)
+			goto err;
+	}
+
+	asoc_simple_debug_info(priv);
+
+	ret = devm_snd_soc_register_card(dev, card);
+err:
+	devm_kfree(dev, li);
+
+	if ((ret < 0) && (ret != -EPROBE_DEFER))
+		dev_err(dev, "parse error %d\n", ret);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(audio_graph2_parse_of);
+
+static int graph_probe(struct platform_device *pdev)
+{
+	struct asoc_simple_priv *priv;
+	struct device *dev = &pdev->dev;
+
+	/* Allocate the private data and the DAI link array */
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	return audio_graph2_parse_of(priv, dev, NULL);
+}
+
+static const struct of_device_id graph_of_match[] = {
+	{ .compatible = "audio-graph-card2", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, graph_of_match);
+
+static struct platform_driver graph_card = {
+	.driver = {
+		.name = "asoc-audio-graph-card2",
+		.pm = &snd_soc_pm_ops,
+		.of_match_table = graph_of_match,
+	},
+	.probe	= graph_probe,
+	.remove	= asoc_simple_remove,
+};
+module_platform_driver(graph_card);
+
+MODULE_ALIAS("platform:asoc-audio-graph-card2");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ASoC Audio Graph Sound Card2");
+MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>");
-- 
2.25.1



More information about the Alsa-devel mailing list