This will add durio sound driver to rpi 3.18.y

arch/arm/boot/dts/duriosound-dac-overlay.dts

@@ -0,0 +1,34 @@
+// Definitions for DURIOSOUND DAC
+/dts-v1/;
+/plugin/;
+
+/ {
+	compatible = "brcm,bcm2708";
+
+	fragment@0 {
+		target = <&sound>;
+		__overlay__ {
+			compatible = "duriosound,duriosound-dac";
+			i2s-controller = <&i2s>;
+			status = "okay";
+		};
+	};
+
+	fragment@1 {
+		target = <&i2s>;
+		__overlay__ {
+			status = "okay";
+		};
+	};
+
+	fragment@2 {
+		target-path = "/";
+		__overlay__ {
+			pcm5102a-codec {
+				#sound-dai-cells = <0>;
+				compatible = "ti,pcm5102a";
+				status = "okay";
+			};
+		};
+	};
+};

arch/arm/configs/bcm2709_defconfig

@@ -798,6 +798,7 @@ CONFIG_SND_BCM2708_SOC_HIFIBERRY_DIGI=m
 CONFIG_SND_BCM2708_SOC_HIFIBERRY_AMP=m
 CONFIG_SND_BCM2708_SOC_RPI_DAC=m
 CONFIG_SND_BCM2708_SOC_IQAUDIO_DAC=m
+CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC=m
 CONFIG_SND_SIMPLE_CARD=m
 CONFIG_SOUND_PRIME=m
 CONFIG_HIDRAW=y

arch/arm/configs/bcmrpi_defconfig

@@ -792,6 +792,7 @@ CONFIG_SND_BCM2708_SOC_HIFIBERRY_DIGI=m
 CONFIG_SND_BCM2708_SOC_HIFIBERRY_AMP=m
 CONFIG_SND_BCM2708_SOC_RPI_DAC=m
 CONFIG_SND_BCM2708_SOC_IQAUDIO_DAC=m
+CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC=m
 CONFIG_SND_SIMPLE_CARD=m
 CONFIG_SOUND_PRIME=m
 CONFIG_HIDRAW=y

arch/arm/mach-bcm2708/bcm2708.c

@@ -733,6 +733,20 @@ static struct i2c_board_info __initdata snd_pcm512x_i2c_devices[] = {
 };
 #endif
 
+#if defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC) || defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC_MODULE)
+static struct platform_device snd_duriosound_dac_device = {
+        .name = "snd-hifiberry-dac",
+        .id = 0,
+        .num_resources = 0,
+};
+
+static struct platform_device snd_pcm5102a_durio_codec_device = {
+        .name = "pcm5102a-codec",
+        .id = -1,
+        .num_resources = 0,
+};
+#endif
+
 int __init bcm_register_device(struct platform_device *pdev)
 {
 	int ret;
@@ -932,6 +946,11 @@ void __init bcm2708_init(void)
         i2c_register_board_info_dt(1, snd_pcm512x_i2c_devices, ARRAY_SIZE(snd_pcm512x_i2c_devices));
 #endif
 
+#if defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC) || defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC_MODULE)
+        bcm_register_device_dt(&snd_duriosound_dac_device);
+        bcm_register_device_dt(&snd_pcm5102a_durio_codec_device);
+#endif
+
 
 	for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
 		struct amba_device *d = amba_devs[i];

arch/arm/mach-bcm2709/bcm2709.c

@@ -755,6 +755,20 @@ static struct i2c_board_info __initdata snd_pcm512x_i2c_devices[] = {
 };
 #endif
 
+#if defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC) || defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC_MODULE)
+static struct platform_device snd_duriosound_dac_device = {
+        .name = "snd-hifiberry-dac",
+        .id = 0,
+        .num_resources = 0,
+};
+
+static struct platform_device snd_pcm5102a_durio_codec_device = {
+        .name = "pcm5102a-codec",
+        .id = -1,
+        .num_resources = 0,
+};
+#endif
+
 int __init bcm_register_device(struct platform_device *pdev)
 {
 	int ret;
@@ -954,6 +968,11 @@ void __init bcm2709_init(void)
         i2c_register_board_info_dt(1, snd_pcm512x_i2c_devices, ARRAY_SIZE(snd_pcm512x_i2c_devices));
 #endif
 
+#if defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC) || defined(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC_MODULE)
+        bcm_register_device_dt(&snd_duriosound_dac_device);
+        bcm_register_device_dt(&snd_pcm5102a_durio_codec_device);
+#endif
+
 
 	for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
 		struct amba_device *d = amba_devs[i];

sound/soc/bcm/Kconfig

@@ -60,3 +60,11 @@ config SND_BCM2708_SOC_IQAUDIO_DAC
 	select SND_SOC_PCM512x_I2C
 	help
 	  Say Y or M if you want to add support for IQaudIO-DAC.
+
+config SND_BCM2708_SOC_DURIOSOUND_DAC
+        tristate "Support for DurioSound DAC"
+        depends on SND_BCM2708_SOC_I2S
+        select SND_SOC_PCM5102A
+        help
+         Say Y or M if you want to add support for DurioSound DAC.
+

sound/soc/bcm/Makefile

@@ -15,10 +15,12 @@ snd-soc-hifiberry-digi-objs := hifiberry_digi.o
 snd-soc-hifiberry-amp-objs := hifiberry_amp.o
 snd-soc-rpi-dac-objs := rpi-dac.o
 snd-soc-iqaudio-dac-objs := iqaudio-dac.o
+snd-soc-duriosound-dac-objs := duriosound-dac.o
 
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DAC) += snd-soc-hifiberry-dac.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DACPLUS) += snd-soc-hifiberry-dacplus.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DIGI) += snd-soc-hifiberry-digi.o
 obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_AMP) += snd-soc-hifiberry-amp.o
 obj-$(CONFIG_SND_BCM2708_SOC_RPI_DAC) += snd-soc-rpi-dac.o
 obj-$(CONFIG_SND_BCM2708_SOC_IQAUDIO_DAC) += snd-soc-iqaudio-dac.o
+obj-$(CONFIG_SND_BCM2708_SOC_DURIOSOUND_DAC) += snd-soc-duriosound-dac.o

sound/soc/bcm/duriosound-dac.c

@@ -0,0 +1,106 @@
+/*
+ * ASoC Driver for DurioSound-DAC.
+ *
+ * Author :	Pitichai Pitimaneeyakul <[email protected]>
+ *		Copyright 2014
+ *
+ *	    based on code by Florian Meier <[email protected]>
+ *
+ * This Module is rewritten from rpi-dac.c and it is modified to 
+ * use pcm5102a as codec to support DurioSound DAC.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/jack.h>
+
+static int snd_rpi_duriosound_dac_init(struct snd_soc_pcm_runtime *rtd)
+{
+	return 0;
+}
+
+static int snd_rpi_duriosound_dac_hw_params(struct snd_pcm_substream *substream,
+				       struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
+
+	unsigned int sample_bits =
+		snd_pcm_format_physical_width(params_format(params));
+
+	return snd_soc_dai_set_bclk_ratio(cpu_dai, sample_bits * 2);
+}
+
+/* machine stream operations */
+static struct snd_soc_ops snd_rpi_duriosound_dac_ops = {
+	.hw_params = snd_rpi_duriosound_dac_hw_params,
+};
+
+static struct snd_soc_dai_link snd_rpi_duriosound_dac_dai[] = {
+{
+	.name		= "DurioSound-DAC",
+	.stream_name	= "DurioSound-DAC HiFi",
+	.cpu_dai_name	= "bcm2708-i2s.0",
+	.codec_dai_name	= "pcm5102a-hifi",
+	.platform_name	= "bcm2708-i2s.0",
+	.codec_name	= "pcm5102a-codec",
+	.dai_fmt	= SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
+				SND_SOC_DAIFMT_CBS_CFS,
+	.ops		= &snd_rpi_duriosound_dac_ops,
+	.init		= snd_rpi_duriosound_dac_init,
+},
+};
+
+/* audio machine driver */
+static struct snd_soc_card snd_rpi_duriosound_dac = {
+	.name         = "snd_rpi_duriosound_dac",
+	.dai_link     = snd_rpi_duriosound_dac_dai,
+	.num_links    = ARRAY_SIZE(snd_rpi_duriosound_dac_dai),
+};
+
+static int snd_rpi_duriosound_dac_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+
+	snd_rpi_duriosound_dac.dev = &pdev->dev;
+	ret = snd_soc_register_card(&snd_rpi_duriosound_dac);
+	if (ret)
+		dev_err(&pdev->dev, "snd_soc_register_card() failed: %d\n", ret);
+
+	return ret;
+}
+
+static int snd_rpi_duriosound_dac_remove(struct platform_device *pdev)
+{
+	return snd_soc_unregister_card(&snd_rpi_duriosound_dac);
+}
+
+static struct platform_driver snd_rpi_duriosound_dac_driver = {
+        .driver = {
+                .name   = "snd-duriosound-dac",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = snd_rpi_duriosound_dac_probe,
+        .remove         = snd_rpi_duriosound_dac_remove,
+};
+
+module_platform_driver(snd_rpi_duriosound_dac_driver);
+
+MODULE_AUTHOR("Pitichai Pitimaneeyakul <[email protected]>");
+MODULE_DESCRIPTION("ASoC Driver for DurioSound-DAC");
+MODULE_LICENSE("GPL v2");