ASoC: fsl: Add S/PDIF machine driver

This patch implements a device-tree-only machine driver for Freescale
i.MX series Soc. It works with spdif_transmitter/spdif_receiver and
fsl_spdif.c drivers.
Signed-off-by: Nicolin Chen <b42378@freescale.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Documentation/devicetree/bindings/sound/imx-audio-spdif.txt

+Freescale i.MX audio complex with S/PDIF transceiver
+
+Required properties:
+
+  - compatible : "fsl,imx-audio-spdif"
+
+  - model : The user-visible name of this sound complex
+
+  - spdif-controller : The phandle of the i.MX S/PDIF controller
+
+
+Optional properties:
+
+  - spdif-out : This is a boolean property. If present, the transmitting
+    function of S/PDIF will be enabled, indicating there's a physical
+    S/PDIF out connector/jack on the board or it's connecting to some
+    other IP block, such as an HDMI encoder/display-controller.
+
+  - spdif-in : This is a boolean property. If present, the receiving
+    function of S/PDIF will be enabled, indicating there's a physical
+    S/PDIF in connector/jack on the board.
+
+* Note: At least one of these two properties should be set in the DT binding.
+
+
+Example:
+
+sound-spdif {
+	compatible = "fsl,imx-audio-spdif";
+	model = "imx-spdif";
+	spdif-controller = <&spdif>;
+	spdif-out;
+	spdif-in;
+};

sound/soc/fsl/Kconfig

@@ -193,6 +193,17 @@ config SND_SOC_IMX_SGTL5000
 	  Say Y if you want to add support for SoC audio on an i.MX board with
 	  a sgtl5000 codec.
 
+config SND_SOC_IMX_SPDIF
+	tristate "SoC Audio support for i.MX boards with S/PDIF"
+	select SND_SOC_IMX_PCM_DMA
+	select SND_SOC_FSL_SPDIF
+	select SND_SOC_FSL_UTILS
+	select SND_SOC_SPDIF
+	help
+	  SoC Audio support for i.MX boards with S/PDIF
+	  Say Y if you want to add support for SoC audio on an i.MX board with
+	  a S/DPDIF.
+
 config SND_SOC_IMX_MC13783
 	tristate "SoC Audio support for I.MX boards with mc13783"
 	depends on MFD_MC13783 && ARM

sound/soc/fsl/Makefile

@@ -45,6 +45,7 @@ snd-soc-mx27vis-aic32x4-objs := mx27vis-aic32x4.o
 snd-soc-wm1133-ev1-objs := wm1133-ev1.o
 snd-soc-imx-sgtl5000-objs := imx-sgtl5000.o
 snd-soc-imx-wm8962-objs := imx-wm8962.o
+snd-soc-imx-spdif-objs :=imx-spdif.o
 snd-soc-imx-mc13783-objs := imx-mc13783.o
 
 obj-$(CONFIG_SND_SOC_EUKREA_TLV320) += snd-soc-eukrea-tlv320.o
@@ -53,4 +54,5 @@ obj-$(CONFIG_SND_SOC_MX27VIS_AIC32X4) += snd-soc-mx27vis-aic32x4.o
 obj-$(CONFIG_SND_MXC_SOC_WM1133_EV1) += snd-soc-wm1133-ev1.o
 obj-$(CONFIG_SND_SOC_IMX_SGTL5000) += snd-soc-imx-sgtl5000.o
 obj-$(CONFIG_SND_SOC_IMX_WM8962) += snd-soc-imx-wm8962.o
+obj-$(CONFIG_SND_SOC_IMX_SPDIF) += snd-soc-imx-spdif.o
 obj-$(CONFIG_SND_SOC_IMX_MC13783) += snd-soc-imx-mc13783.o

sound/soc/fsl/imx-spdif.c

+/*
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <sound/soc.h>
+
+struct imx_spdif_data {
+	struct snd_soc_dai_link dai[2];
+	struct snd_soc_card card;
+	struct platform_device *txdev;
+	struct platform_device *rxdev;
+};
+
+static int imx_spdif_audio_probe(struct platform_device *pdev)
+{
+	struct device_node *spdif_np, *np = pdev->dev.of_node;
+	struct imx_spdif_data *data;
+	int ret = 0, num_links = 0;
+
+	spdif_np = of_parse_phandle(np, "spdif-controller", 0);
+	if (!spdif_np) {
+		dev_err(&pdev->dev, "failed to find spdif-controller\n");
+		ret = -EINVAL;
+		goto end;
+	}
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		ret = -ENOMEM;
+		goto end;
+	}
+
+	if (of_property_read_bool(np, "spdif-out")) {
+		data->dai[num_links].name = "S/PDIF TX";
+		data->dai[num_links].stream_name = "S/PDIF PCM Playback";
+		data->dai[num_links].codec_dai_name = "dit-hifi";
+		data->dai[num_links].codec_name = "spdif-dit";
+		data->dai[num_links].cpu_of_node = spdif_np;
+		data->dai[num_links].platform_of_node = spdif_np;
+		num_links++;
+
+		data->txdev = platform_device_register_simple("spdif-dit", -1, NULL, 0);
+		if (IS_ERR(data->txdev)) {
+			ret = PTR_ERR(data->txdev);
+			dev_err(&pdev->dev, "register dit failed: %d\n", ret);
+			goto end;
+		}
+	}
+
+	if (of_property_read_bool(np, "spdif-in")) {
+		data->dai[num_links].name = "S/PDIF RX";
+		data->dai[num_links].stream_name = "S/PDIF PCM Capture";
+		data->dai[num_links].codec_dai_name = "dir-hifi";
+		data->dai[num_links].codec_name = "spdif-dir";
+		data->dai[num_links].cpu_of_node = spdif_np;
+		data->dai[num_links].platform_of_node = spdif_np;
+		num_links++;
+
+		data->rxdev = platform_device_register_simple("spdif-dir", -1, NULL, 0);
+		if (IS_ERR(data->rxdev)) {
+			ret = PTR_ERR(data->rxdev);
+			dev_err(&pdev->dev, "register dir failed: %d\n", ret);
+			goto error_dit;
+		}
+	}
+
+	if (!num_links) {
+		dev_err(&pdev->dev, "no enabled S/PDIF DAI link\n");
+		goto error_dir;
+	}
+
+	data->card.dev = &pdev->dev;
+	data->card.num_links = num_links;
+	data->card.dai_link = data->dai;
+
+	ret = snd_soc_of_parse_card_name(&data->card, "model");
+	if (ret)
+		goto error_dir;
+
+	ret = snd_soc_register_card(&data->card);
+	if (ret) {
+		dev_err(&pdev->dev, "snd_soc_register_card failed: %d\n", ret);
+		goto error_dir;
+	}
+
+	platform_set_drvdata(pdev, data);
+
+	goto end;
+
+error_dir:
+	if (data->rxdev)
+		platform_device_unregister(data->rxdev);
+error_dit:
+	if (data->txdev)
+		platform_device_unregister(data->txdev);
+end:
+	if (spdif_np)
+		of_node_put(spdif_np);
+
+	return ret;
+}
+
+static int imx_spdif_audio_remove(struct platform_device *pdev)
+{
+	struct imx_spdif_data *data = platform_get_drvdata(pdev);
+
+	if (data->rxdev)
+		platform_device_unregister(data->rxdev);
+	if (data->txdev)
+		platform_device_unregister(data->txdev);
+
+	snd_soc_unregister_card(&data->card);
+
+	return 0;
+}
+
+static const struct of_device_id imx_spdif_dt_ids[] = {
+	{ .compatible = "fsl,imx-audio-spdif", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_spdif_dt_ids);
+
+static struct platform_driver imx_spdif_driver = {
+	.driver = {
+		.name = "imx-spdif",
+		.owner = THIS_MODULE,
+		.of_match_table = imx_spdif_dt_ids,
+	},
+	.probe = imx_spdif_audio_probe,
+	.remove = imx_spdif_audio_remove,
+};
+
+module_platform_driver(imx_spdif_driver);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("Freescale i.MX S/PDIF machine driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:imx-spdif");