ASoC: simple-card: add Device Tree support

Simple-Card:

Simple-Card specifies audio DAI connection of SoC <-> codec.

Required properties:

- compatible				: "simple-audio-card"

Optional properties:

- simple-audio-card,format		: CPU/CODEC common audio format.

					"i2s", "right_j", "left_j" , "dsp_a"

					"dsp_b", "ac97", "pdm", "msb", "lsb"

Required subnodes:

- simple-audio-card,cpu			: CPU   sub-node

- simple-audio-card,codec		: CODEC sub-node

Required CPU/CODEC subnodes properties:

- sound-dai				: phandle and port of CPU/CODEC

Optional CPU/CODEC subnodes properties:

- format				: CPU/CODEC specific audio format if needed.

					  see simple-audio-card,format

- frame-master				: bool property. add this if subnode is frame master

- bitclock-master			: bool property. add this if subnode is bitclock master

- bitclock-inversion			: bool property. add this if subnode has clock inversion

- frame-inversion			: bool property. add this if subnode has frame inversion

- clocks / system-clock-frequency	: specify subnode's clock if needed.

					  it can be specified via "clocks" if system has

					  clock node (= common clock), or "system-clock-frequency"

					  (if system doens't support common clock)

Example:

sound {

	compatible = "simple-audio-card";

	simple-audio-card,format = "left_j";

	simple-audio-card,cpu {

		sound-dai = <&sh_fsi2 0>;

	};

	simple-audio-card,codec {

		sound-dai = <&ak4648>;

		bitclock-master;

		frame-master;

		clocks = <&osc>;

	};

};

&i2c0 {

	ak4648: ak4648@12 {

		#sound-dai-cells = <0>;

		compatible = "asahi-kasei,ak4648";

		reg = <0x12>;

	};

};

sh_fsi2: sh_fsi2@ec230000 {

	#sound-dai-cells = <1>;

	compatible = "renesas,sh_fsi2";

	reg = <0xec230000 0x400>;

	interrupt-parent = <&gic>;

	interrupts = <0 146 0x4>;

};

 * 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/of.h>

#include <linux/platform_device.h>

#include <linux/module.h>

#include <sound/simple_card.h>

	return 0;

}

static int

asoc_simple_card_sub_parse_of(struct device_node *np,

			      struct asoc_simple_dai *dai,

			      struct device_node **node)

{

	struct clk *clk;

	int ret;

	/*

	 * get node via "sound-dai = <&phandle port>"

	 * it will be used as xxx_of_node on soc_bind_dai_link()

	 */

	*node = of_parse_phandle(np, "sound-dai", 0);

	if (!*node)

		return -ENODEV;

	/* get dai->name */

	ret = snd_soc_of_get_dai_name(np, &dai->name);

	if (ret < 0)

		goto parse_error;

	/*

	 * bitclock-inversion, frame-inversion

	 * bitclock-master,    frame-master

	 * and specific "format" if it has

	 */

	dai->fmt = snd_soc_of_parse_daifmt(np, NULL);

	/*

	 * dai->sysclk come from

	 *  "clocks = <&xxx>" (if system has common clock)

	 *  or "system-clock-frequency = <xxx>"

	 */

	clk = of_clk_get(np, 0);

	if (IS_ERR(clk))

		of_property_read_u32(np,

				     "system-clock-frequency",

				     &dai->sysclk);

	else

		dai->sysclk = clk_get_rate(clk);

	ret = 0;

parse_error:

	of_node_put(*node);

	return ret;

}

static int asoc_simple_card_parse_of(struct device_node *node,

				     struct asoc_simple_card_info *info,

				     struct device *dev,

				     struct device_node **of_cpu,

				     struct device_node **of_codec,

				     struct device_node **of_platform)

{

	struct device_node *np;

	char *name;

	int ret = 0;

	/* get CPU/CODEC common format via simple-audio-card,format */

	info->daifmt = snd_soc_of_parse_daifmt(node, "simple-audio-card,") &

		(SND_SOC_DAIFMT_FORMAT_MASK | SND_SOC_DAIFMT_INV_MASK);

	/* CPU sub-node */

	ret = -EINVAL;

	np = of_get_child_by_name(node, "simple-audio-card,cpu");

	if (np)

		ret = asoc_simple_card_sub_parse_of(np,

						  &info->cpu_dai,

						  of_cpu);

	if (ret < 0)

		return ret;

	/* CODEC sub-node */

	ret = -EINVAL;

	np = of_get_child_by_name(node, "simple-audio-card,codec");

	if (np)

		ret = asoc_simple_card_sub_parse_of(np,

						  &info->codec_dai,

						  of_codec);

	if (ret < 0)

		return ret;

	/* card name is created from CPU/CODEC dai name */

	name = devm_kzalloc(dev,

			    strlen(info->cpu_dai.name)   +

			    strlen(info->codec_dai.name) + 2,

			    GFP_KERNEL);

	sprintf(name, "%s-%s", info->cpu_dai.name, info->codec_dai.name);

	info->name = info->card = name;

	/* simple-card assumes platform == cpu */

	*of_platform = *of_cpu;

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

	dev_dbg(dev, "platform : %04x\n", info->daifmt);

	dev_dbg(dev, "cpu : %s / %04x / %d\n",

		info->cpu_dai.name,

		info->cpu_dai.fmt,

		info->cpu_dai.sysclk);

	dev_dbg(dev, "codec : %s / %04x / %d\n",

		info->codec_dai.name,

		info->codec_dai.fmt,

		info->codec_dai.sysclk);

	return 0;

}

static int asoc_simple_card_probe(struct platform_device *pdev)

{

	struct asoc_simple_card_info *cinfo = pdev->dev.platform_data;

	struct asoc_simple_card_info *cinfo;

	struct device_node *np = pdev->dev.of_node;

	struct device_node *of_cpu, *of_codec, *of_platform;

	struct device *dev = &pdev->dev;

	cinfo		= NULL;

	of_cpu		= NULL;

	of_codec	= NULL;

	of_platform	= NULL;

	if (np && of_device_is_available(np)) {

		cinfo = devm_kzalloc(dev, sizeof(*cinfo), GFP_KERNEL);

		if (cinfo) {

			int ret;

			ret = asoc_simple_card_parse_of(np, cinfo, dev,

							&of_cpu,

							&of_codec,

							&of_platform);

			if (ret < 0) {

				if (ret != -EPROBE_DEFER)

					dev_err(dev, "parse error %d\n", ret);

				return ret;

			}

		}

	} else {

		cinfo = pdev->dev.platform_data;

	}

	if (!cinfo) {

		dev_err(dev, "no info for asoc-simple-card\n");

		return -EINVAL;

	if (!cinfo->name	||

	    !cinfo->card	||

	    !cinfo->codec	||

	    !cinfo->platform	||

	    !cinfo->cpu_dai.name ||

	    !cinfo->codec_dai.name) {

	    !cinfo->codec_dai.name	||

	    !(cinfo->codec		|| of_codec)	||

	    !(cinfo->platform		|| of_platform)	||

	    !(cinfo->cpu_dai.name	|| of_cpu)) {

		dev_err(dev, "insufficient asoc_simple_card_info settings\n");

		return -EINVAL;

	}

	cinfo->snd_link.platform_name	= cinfo->platform;

	cinfo->snd_link.codec_name	= cinfo->codec;

	cinfo->snd_link.codec_dai_name	= cinfo->codec_dai.name;

	cinfo->snd_link.cpu_of_node	= of_cpu;

	cinfo->snd_link.codec_of_node	= of_codec;

	cinfo->snd_link.platform_of_node = of_platform;

	cinfo->snd_link.init		= asoc_simple_card_dai_init;

	/*

	return snd_soc_unregister_card(&cinfo->snd_card);

}

static const struct of_device_id asoc_simple_of_match[] = {

	{ .compatible = "simple-audio-card", },

	{},

};

MODULE_DEVICE_TABLE(of, asoc_simple_of_match);

static struct platform_driver asoc_simple_card = {

	.driver = {

		.name	= "asoc-simple-card",

		.owner = THIS_MODULE,

		.of_match_table = asoc_simple_of_match,

	},

	.probe		= asoc_simple_card_probe,

	.remove		= asoc_simple_card_remove,