diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
index b1749bc..6e04fc2 100644
--- a/sound/soc/Kconfig
+++ b/sound/soc/Kconfig
@@ -30,6 +30,7 @@
 source "sound/soc/davinci/Kconfig"
 source "sound/soc/fsl/Kconfig"
 source "sound/soc/imx/Kconfig"
+source "sound/soc/nuc900/Kconfig"
 source "sound/soc/omap/Kconfig"
 source "sound/soc/pxa/Kconfig"
 source "sound/soc/s3c24xx/Kconfig"
diff --git a/sound/soc/Makefile b/sound/soc/Makefile
index 1470141..ccec241 100644
--- a/sound/soc/Makefile
+++ b/sound/soc/Makefile
@@ -8,6 +8,7 @@
 obj-$(CONFIG_SND_SOC)	+= davinci/
 obj-$(CONFIG_SND_SOC)	+= fsl/
 obj-$(CONFIG_SND_SOC)   += imx/
+obj-$(CONFIG_SND_SOC)	+= nuc900/
 obj-$(CONFIG_SND_SOC)	+= omap/
 obj-$(CONFIG_SND_SOC)	+= pxa/
 obj-$(CONFIG_SND_SOC)	+= s3c24xx/
diff --git a/sound/soc/nuc900/Kconfig b/sound/soc/nuc900/Kconfig
new file mode 100644
index 0000000..a0ed1c6
--- /dev/null
+++ b/sound/soc/nuc900/Kconfig
@@ -0,0 +1,27 @@
+##
+## NUC900 series AC97 API
+##
+config SND_SOC_NUC900
+	tristate "SoC Audio for NUC900 series"
+	depends on ARCH_W90X900
+	help
+	  This option enables support for AC97 mode on the NUC900 SoC.
+
+config SND_SOC_NUC900_AC97
+	tristate
+	select AC97_BUS
+	select SND_AC97_CODEC
+	select SND_SOC_AC97_BUS
+
+
+##
+## Boards
+##
+config SND_SOC_NUC900EVB
+	tristate "NUC900 AC97 support for demo board"
+	depends on SND_SOC_NUC900
+	select SND_SOC_NUC900_AC97
+	select SND_SOC_AC97_CODEC
+	help
+	  Select this option to enable audio (AC97) on the
+	  NUC900 demoboard.
diff --git a/sound/soc/nuc900/Makefile b/sound/soc/nuc900/Makefile
new file mode 100644
index 0000000..7e46c71
--- /dev/null
+++ b/sound/soc/nuc900/Makefile
@@ -0,0 +1,11 @@
+# NUC900 series audio
+snd-soc-nuc900-pcm-objs := nuc900-pcm.o
+snd-soc-nuc900-ac97-objs := nuc900-ac97.o
+
+obj-$(CONFIG_SND_SOC_NUC900) += snd-soc-nuc900-pcm.o
+obj-$(CONFIG_SND_SOC_NUC900_AC97) += snd-soc-nuc900-ac97.o
+
+# Boards
+snd-soc-nuc900-audio-objs := nuc900-audio.o
+
+obj-$(CONFIG_SND_SOC_NUC900EVB) += snd-soc-nuc900-audio.o
diff --git a/sound/soc/nuc900/nuc900-ac97.c b/sound/soc/nuc900/nuc900-ac97.c
new file mode 100644
index 0000000..f7b44e0
--- /dev/null
+++ b/sound/soc/nuc900/nuc900-ac97.c
@@ -0,0 +1,442 @@
+/*
+ * Copyright (c) 2009-2010 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/suspend.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <linux/device.h>
+#include <linux/clk.h>
+
+#include <mach/mfp.h>
+
+#include "nuc900-auido.h"
+
+static DEFINE_MUTEX(ac97_mutex);
+struct nuc900_audio *nuc900_ac97_data;
+
+static int nuc900_checkready(void)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+
+	if (!(AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS0) & CODEC_READY))
+		return -EPERM;
+
+	return 0;
+}
+
+/* AC97 controller reads codec register */
+static unsigned short nuc900_ac97_read(struct snd_ac97 *ac97,
+					unsigned short reg)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	unsigned long timeout = 0x10000, val;
+
+	mutex_lock(&ac97_mutex);
+
+	val = nuc900_checkready();
+	if (!!val) {
+		dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");
+		goto out;
+	}
+
+	/* set the R_WB bit and write register index */
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS1, R_WB | reg);
+
+	/* set the valid frame bit and valid slots */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
+	val |= (VALID_FRAME | SLOT1_VALID);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, val);
+
+	udelay(100);
+
+	/* polling the AC_R_FINISH */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
+	val &= AC_R_FINISH;
+	while (!val && timeout--)
+		mdelay(1);
+
+	if (!timeout) {
+		dev_err(nuc900_audio->dev, "AC97 read register time out !\n");
+		val = -EPERM;
+		goto out;
+	}
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0) ;
+	val &= ~SLOT1_VALID;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, val);
+
+	if (AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS1) >> 2 != reg) {
+		dev_err(nuc900_audio->dev,
+				"R_INDEX of REG_ACTL_ACIS1 not match!\n");
+	}
+
+	udelay(100);
+	val = (AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS2) & 0xFFFF);
+
+out:
+	mutex_unlock(&ac97_mutex);
+	return val;
+}
+
+/* AC97 controller writes to codec register */
+static void nuc900_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
+				unsigned short val)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	unsigned long tmp, timeout = 0x10000;
+
+	mutex_lock(&ac97_mutex);
+
+	tmp = nuc900_checkready();
+	if (!!tmp)
+		dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");
+
+	/* clear the R_WB bit and write register index */
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS1, reg);
+
+	/* write register value */
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS2, val);
+
+	/* set the valid frame bit and valid slots */
+	tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
+	tmp |= SLOT1_VALID | SLOT2_VALID | VALID_FRAME;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);
+
+	udelay(100);
+
+	/* polling the AC_W_FINISH */
+	tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
+	tmp &= AC_W_FINISH;
+	while (tmp && timeout--)
+		mdelay(1);
+
+	if (!timeout)
+		dev_err(nuc900_audio->dev, "AC97 write register time out !\n");
+
+	tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
+	tmp &= ~(SLOT1_VALID | SLOT2_VALID);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);
+
+	mutex_unlock(&ac97_mutex);
+
+}
+
+static void nuc900_ac97_warm_reset(struct snd_ac97 *ac97)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	unsigned long val;
+
+	mutex_lock(&ac97_mutex);
+
+	/* warm reset AC 97 */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
+	val |= AC_W_RES;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);
+
+	udelay(1000);
+
+	val = nuc900_checkready();
+	if (!!val)
+		dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");
+
+	mutex_unlock(&ac97_mutex);
+}
+
+static void nuc900_ac97_cold_reset(struct snd_ac97 *ac97)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	unsigned long val;
+
+	mutex_lock(&ac97_mutex);
+
+	/* reset Audio Controller */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+	val |= ACTL_RESET_BIT;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+	udelay(1000);
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+	val &= (~ACTL_RESET_BIT);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+	udelay(1000);
+
+	/* reset AC-link interface */
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+	val |= AC_RESET;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+	udelay(1000);
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+	val &= ~AC_RESET;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+	udelay(1000);
+
+	/* cold reset AC 97 */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
+	val |= AC_C_RES;
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);
+
+	udelay(1000);
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
+	val &= (~AC_C_RES);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);
+
+	udelay(1000);
+
+	mutex_unlock(&ac97_mutex);
+
+}
+
+/* AC97 controller operations */
+struct snd_ac97_bus_ops soc_ac97_ops = {
+	.read		= nuc900_ac97_read,
+	.write		= nuc900_ac97_write,
+	.reset		= nuc900_ac97_cold_reset,
+	.warm_reset	= nuc900_ac97_warm_reset,
+}
+EXPORT_SYMBOL_GPL(soc_ac97_ops);
+
+static int nuc900_ac97_trigger(struct snd_pcm_substream *substream,
+				int cmd, struct snd_soc_dai *dai)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	int ret, stype = SUBSTREAM_TYPE(substream);
+	unsigned long val, tmp;
+
+	ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+		if (PCM_TX == stype) {
+			tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
+			tmp |= (SLOT3_VALID | SLOT4_VALID | VALID_FRAME);
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);
+
+			tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_PSR);
+			tmp |= (P_DMA_END_IRQ | P_DMA_MIDDLE_IRQ);
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, tmp);
+			val |= AC_PLAY;
+		} else {
+			tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_RSR);
+			tmp |= (R_DMA_END_IRQ | R_DMA_MIDDLE_IRQ);
+
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, tmp);
+			val |= AC_RECORD;
+		}
+
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+		if (PCM_TX == stype) {
+			tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
+			tmp &= ~(SLOT3_VALID | SLOT4_VALID);
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);
+
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, RESET_PRSR);
+			val &= ~AC_PLAY;
+		} else {
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, RESET_PRSR);
+			val &= ~AC_RECORD;
+		}
+
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int nuc900_ac97_probe(struct platform_device *pdev,
+					struct snd_soc_dai *dai)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+	unsigned long val;
+
+	mutex_lock(&ac97_mutex);
+
+	/* enable unit clock */
+	clk_enable(nuc900_audio->clk);
+
+	/* enable audio controller and AC-link interface */
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
+	val |= (IIS_AC_PIN_SEL | ACLINK_EN);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
+
+	mutex_unlock(&ac97_mutex);
+
+	return 0;
+}
+
+static void nuc900_ac97_remove(struct platform_device *pdev,
+						struct snd_soc_dai *dai)
+{
+	struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
+
+	clk_disable(nuc900_audio->clk);
+}
+
+static struct snd_soc_dai_ops nuc900_ac97_dai_ops = {
+	.trigger	= nuc900_ac97_trigger,
+};
+
+struct snd_soc_dai nuc900_ac97_dai = {
+	.name			= "nuc900-ac97",
+	.probe			= nuc900_ac97_probe,
+	.remove			= nuc900_ac97_remove,
+	.ac97_control		= 1,
+	.playback = {
+		.rates		= SNDRV_PCM_RATE_8000_48000,
+		.formats	= SNDRV_PCM_FMTBIT_S16_LE,
+		.channels_min	= 1,
+		.channels_max	= 2,
+	},
+	.capture = {
+		.rates		= SNDRV_PCM_RATE_8000_48000,
+		.formats	= SNDRV_PCM_FMTBIT_S16_LE,
+		.channels_min	= 1,
+		.channels_max	= 2,
+	},
+	.ops = &nuc900_ac97_dai_ops,
+}
+EXPORT_SYMBOL_GPL(nuc900_ac97_dai);
+
+static int __devinit nuc900_ac97_drvprobe(struct platform_device *pdev)
+{
+	struct nuc900_audio *nuc900_audio;
+	int ret;
+
+	if (nuc900_ac97_data)
+		return -EBUSY;
+
+	nuc900_audio = kzalloc(sizeof(struct nuc900_audio), GFP_KERNEL);
+	if (!nuc900_audio)
+		return -ENOMEM;
+
+	spin_lock_init(&nuc900_audio->lock);
+
+	nuc900_audio->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!nuc900_audio->res) {
+		ret = -ENODEV;
+		goto out0;
+	}
+
+	if (!request_mem_region(nuc900_audio->res->start,
+			resource_size(nuc900_audio->res), pdev->name)) {
+		ret = -EBUSY;
+		goto out0;
+	}
+
+	nuc900_audio->mmio = ioremap(nuc900_audio->res->start,
+					resource_size(nuc900_audio->res));
+	if (!nuc900_audio->mmio) {
+		ret = -ENOMEM;
+		goto out1;
+	}
+
+	nuc900_audio->clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(nuc900_audio->clk)) {
+		ret = PTR_ERR(nuc900_audio->clk);
+		goto out2;
+	}
+
+	nuc900_audio->irq_num = platform_get_irq(pdev, 0);
+	if (!nuc900_audio->irq_num) {
+		ret = -EBUSY;
+		goto out2;
+	}
+
+	nuc900_ac97_data = nuc900_audio;
+
+	nuc900_audio->dev = nuc900_ac97_dai.dev =  &pdev->dev;
+
+	ret = snd_soc_register_dai(&nuc900_ac97_dai);
+	if (ret)
+		goto out3;
+
+	mfp_set_groupg(nuc900_audio->dev); /* enbale ac97 multifunction pin*/
+
+	return 0;
+
+out3:
+	clk_put(nuc900_audio->clk);
+out2:
+	iounmap(nuc900_audio->mmio);
+out1:
+	release_mem_region(nuc900_audio->res->start,
+					resource_size(nuc900_audio->res));
+out0:
+	kfree(nuc900_audio);
+	return ret;
+}
+
+static int __devexit nuc900_ac97_drvremove(struct platform_device *pdev)
+{
+
+	snd_soc_unregister_dai(&nuc900_ac97_dai);
+
+	clk_put(nuc900_ac97_data->clk);
+	iounmap(nuc900_ac97_data->mmio);
+	release_mem_region(nuc900_ac97_data->res->start,
+				resource_size(nuc900_ac97_data->res));
+
+	nuc900_ac97_data = NULL;
+
+	return 0;
+}
+
+static struct platform_driver nuc900_ac97_driver = {
+	.driver	= {
+		.name	= "nuc900-audio",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= nuc900_ac97_drvprobe,
+	.remove		= __devexit_p(nuc900_ac97_drvremove),
+};
+
+static int __init nuc900_ac97_init(void)
+{
+	return platform_driver_register(&nuc900_ac97_driver);
+}
+
+static void __exit nuc900_ac97_exit(void)
+{
+	platform_driver_unregister(&nuc900_ac97_driver);
+}
+
+module_init(nuc900_ac97_init);
+module_exit(nuc900_ac97_exit);
+
+MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
+MODULE_DESCRIPTION("NUC900 AC97 SoC driver!");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nuc900-ac97");
diff --git a/sound/soc/nuc900/nuc900-audio.c b/sound/soc/nuc900/nuc900-audio.c
new file mode 100644
index 0000000..b33d5b8
--- /dev/null
+++ b/sound/soc/nuc900/nuc900-audio.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2010 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include <sound/soc-dapm.h>
+
+#include "../codecs/ac97.h"
+#include "nuc900-auido.h"
+
+static struct snd_soc_dai_link nuc900evb_ac97_dai = {
+	.name		= "AC97",
+	.stream_name	= "AC97 HiFi",
+	.cpu_dai	= &nuc900_ac97_dai,
+	.codec_dai	= &ac97_dai,
+};
+
+static struct snd_soc_card nuc900evb_audio_machine = {
+	.name		= "NUC900EVB_AC97",
+	.dai_link	= &nuc900evb_ac97_dai,
+	.num_links	= 1,
+	.platform	= &nuc900_soc_platform,
+};
+
+static struct snd_soc_device nuc900evb_ac97_devdata = {
+	.card		= &nuc900evb_audio_machine,
+	.codec_dev	= &soc_codec_dev_ac97,
+};
+
+static struct platform_device *nuc900evb_asoc_dev;
+
+static int __init nuc900evb_audio_init(void)
+{
+	int ret;
+
+	ret = -ENOMEM;
+	nuc900evb_asoc_dev = platform_device_alloc("soc-audio", -1);
+	if (!nuc900evb_asoc_dev)
+		goto out;
+
+	/* nuc900 board audio device */
+	platform_set_drvdata(nuc900evb_asoc_dev, &nuc900evb_ac97_devdata);
+
+	nuc900evb_ac97_devdata.dev = &nuc900evb_asoc_dev->dev;
+	ret = platform_device_add(nuc900evb_asoc_dev);
+
+	if (ret) {
+		platform_device_put(nuc900evb_asoc_dev);
+		nuc900evb_asoc_dev = NULL;
+	}
+
+out:
+	return ret;
+}
+
+static void __exit nuc900evb_audio_exit(void)
+{
+	platform_device_unregister(nuc900evb_asoc_dev);
+}
+
+module_init(nuc900evb_audio_init);
+module_exit(nuc900evb_audio_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("NUC900 Series ASoC audio support");
+MODULE_AUTHOR("Wan ZongShun");
diff --git a/sound/soc/nuc900/nuc900-auido.h b/sound/soc/nuc900/nuc900-auido.h
new file mode 100644
index 0000000..95ac4ef
--- /dev/null
+++ b/sound/soc/nuc900/nuc900-auido.h
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2010 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#ifndef _NUC900_AUDIO_H
+#define _NUC900_AUDIO_H
+
+#include <linux/io.h>
+
+/* Audio Control Registers */
+#define ACTL_CON		0x00
+#define ACTL_RESET		0x04
+#define ACTL_RDSTB		0x08
+#define ACTL_RDST_LENGTH	0x0C
+#define ACTL_RDSTC		0x10
+#define ACTL_RSR		0x14
+#define ACTL_PDSTB		0x18
+#define ACTL_PDST_LENGTH	0x1C
+#define ACTL_PDSTC		0x20
+#define ACTL_PSR		0x24
+#define ACTL_IISCON		0x28
+#define ACTL_ACCON		0x2C
+#define ACTL_ACOS0		0x30
+#define ACTL_ACOS1		0x34
+#define ACTL_ACOS2		0x38
+#define ACTL_ACIS0		0x3C
+#define ACTL_ACIS1		0x40
+#define ACTL_ACIS2		0x44
+#define ACTL_COUNTER		0x48
+
+/* bit definition of REG_ACTL_CON register */
+#define R_DMA_IRQ		0x1000
+#define T_DMA_IRQ		0x0800
+#define IIS_AC_PIN_SEL		0x0100
+#define FIFO_TH			0x0080
+#define ADC_EN			0x0010
+#define M80_EN			0x0008
+#define ACLINK_EN		0x0004
+#define IIS_EN			0x0002
+
+/* bit definition of REG_ACTL_RESET register */
+#define W5691_PLAY		0x20000
+#define ACTL_RESET_BIT		0x10000
+#define RECORD_RIGHT_CHNNEL	0x08000
+#define RECORD_LEFT_CHNNEL	0x04000
+#define PLAY_RIGHT_CHNNEL	0x02000
+#define PLAY_LEFT_CHNNEL	0x01000
+#define DAC_PLAY		0x00800
+#define ADC_RECORD		0x00400
+#define M80_PLAY		0x00200
+#define AC_RECORD		0x00100
+#define AC_PLAY			0x00080
+#define IIS_RECORD		0x00040
+#define IIS_PLAY		0x00020
+#define DAC_RESET		0x00010
+#define ADC_RESET		0x00008
+#define M80_RESET		0x00004
+#define AC_RESET		0x00002
+#define IIS_RESET		0x00001
+
+/* bit definition of REG_ACTL_ACCON register */
+#define AC_BCLK_PU_EN		0x20
+#define AC_R_FINISH		0x10
+#define AC_W_FINISH		0x08
+#define AC_W_RES		0x04
+#define AC_C_RES		0x02
+
+/* bit definition of ACTL_RSR register */
+#define R_FIFO_EMPTY		0x04
+#define R_DMA_END_IRQ		0x02
+#define R_DMA_MIDDLE_IRQ	0x01
+
+/* bit definition of ACTL_PSR register */
+#define P_FIFO_EMPTY		0x04
+#define P_DMA_END_IRQ		0x02
+#define P_DMA_MIDDLE_IRQ	0x01
+
+/* bit definition of ACTL_ACOS0 register */
+#define SLOT1_VALID		0x01
+#define SLOT2_VALID		0x02
+#define SLOT3_VALID		0x04
+#define SLOT4_VALID		0x08
+#define VALID_FRAME		0x10
+
+/* bit definition of ACTL_ACOS1 register */
+#define R_WB			0x80
+
+#define CODEC_READY		0x10
+#define RESET_PRSR		0x00
+#define AUDIO_WRITE(addr, val)	__raw_writel(val, addr)
+#define AUDIO_READ(addr)	__raw_readl(addr)
+#define PCM_TX			0
+#define PCM_RX			1
+#define SUBSTREAM_TYPE(substream) \
+	((substream)->stream == SNDRV_PCM_STREAM_PLAYBACK ? PCM_TX : PCM_RX)
+
+struct nuc900_audio {
+	void __iomem *mmio;
+	spinlock_t lock;
+	dma_addr_t dma_addr[2];
+	unsigned long buffersize[2];
+	unsigned long irq_num;
+	struct snd_pcm_substream *substream;
+	struct resource *res;
+	struct clk *clk;
+	struct device *dev;
+
+};
+
+extern struct nuc900_audio *nuc900_ac97_data;
+extern struct snd_soc_dai nuc900_ac97_dai;
+extern struct snd_soc_platform nuc900_soc_platform;
+
+#endif /*end _NUC900_AUDIO_H */
diff --git a/sound/soc/nuc900/nuc900-pcm.c b/sound/soc/nuc900/nuc900-pcm.c
new file mode 100644
index 0000000..32a503c
--- /dev/null
+++ b/sound/soc/nuc900/nuc900-pcm.c
@@ -0,0 +1,352 @@
+/*
+ * Copyright (c) 2010 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <mach/hardware.h>
+
+#include "nuc900-auido.h"
+
+static const struct snd_pcm_hardware nuc900_pcm_hardware = {
+	.info			= SNDRV_PCM_INFO_INTERLEAVED |
+					SNDRV_PCM_INFO_BLOCK_TRANSFER |
+					SNDRV_PCM_INFO_MMAP |
+					SNDRV_PCM_INFO_MMAP_VALID |
+					SNDRV_PCM_INFO_PAUSE |
+					SNDRV_PCM_INFO_RESUME,
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
+	.channels_min		= 1,
+	.channels_max		= 2,
+	.buffer_bytes_max	= 4*1024,
+	.period_bytes_min	= 1*1024,
+	.period_bytes_max	= 4*1024,
+	.periods_min		= 1,
+	.periods_max		= 1024,
+};
+
+static int nuc900_dma_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+	unsigned long flags, stype = SUBSTREAM_TYPE(substream);
+	int ret = 0;
+
+	spin_lock_irqsave(&nuc900_audio->lock, flags);
+
+	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
+	if (ret < 0)
+		return ret;
+
+	nuc900_audio->substream = substream;
+	nuc900_audio->dma_addr[stype] = runtime->dma_addr;
+	nuc900_audio->buffersize[stype] = params_buffer_bytes(params);
+
+	spin_unlock_irqrestore(&nuc900_audio->lock, flags);
+
+	return ret;
+}
+
+static void nuc900_update_dma_register(struct snd_pcm_substream *substream,
+				dma_addr_t dma_addr, size_t count)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+	void __iomem *mmio_addr, *mmio_len;
+
+	if (SUBSTREAM_TYPE(substream) == PCM_TX) {
+		mmio_addr = nuc900_audio->mmio + ACTL_PDSTB;
+		mmio_len = nuc900_audio->mmio + ACTL_PDST_LENGTH;
+	} else {
+		mmio_addr = nuc900_audio->mmio + ACTL_RDSTB;
+		mmio_len = nuc900_audio->mmio + ACTL_RDST_LENGTH;
+	}
+
+	AUDIO_WRITE(mmio_addr, dma_addr);
+	AUDIO_WRITE(mmio_len, count);
+}
+
+static void nuc900_dma_start(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+	unsigned long val;
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
+	val |= (T_DMA_IRQ | R_DMA_IRQ);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
+}
+
+static void nuc900_dma_stop(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+	unsigned long val;
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
+	val &= ~(T_DMA_IRQ | R_DMA_IRQ);
+	AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);
+}
+
+static irqreturn_t nuc900_dma_interrupt(int irq, void *dev_id)
+{
+	struct snd_pcm_substream *substream = dev_id;
+	struct nuc900_audio *nuc900_audio = substream->runtime->private_data;
+	unsigned long val;
+
+	spin_lock(&nuc900_audio->lock);
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
+
+	if (val & R_DMA_IRQ) {
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | R_DMA_IRQ);
+
+		val = AUDIO_READ(nuc900_audio->mmio + ACTL_RSR);
+
+		if (val & R_DMA_MIDDLE_IRQ) {
+			val |= R_DMA_MIDDLE_IRQ;
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
+		}
+
+		if (val & R_DMA_END_IRQ) {
+			val |= R_DMA_END_IRQ;
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, val);
+		}
+	} else if (val & T_DMA_IRQ) {
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val | T_DMA_IRQ);
+
+		val = AUDIO_READ(nuc900_audio->mmio + ACTL_PSR);
+
+		if (val & P_DMA_MIDDLE_IRQ) {
+			val |= P_DMA_MIDDLE_IRQ;
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
+		}
+
+		if (val & P_DMA_END_IRQ) {
+			val |= P_DMA_END_IRQ;
+			AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, val);
+		}
+	} else {
+		dev_err(nuc900_audio->dev, "Wrong DMA interrupt status!\n");
+		spin_unlock(&nuc900_audio->lock);
+		return IRQ_HANDLED;
+	}
+
+	spin_unlock(&nuc900_audio->lock);
+
+	snd_pcm_period_elapsed(substream);
+
+	return IRQ_HANDLED;
+}
+
+static int nuc900_dma_hw_free(struct snd_pcm_substream *substream)
+{
+	snd_pcm_lib_free_pages(substream);
+	return 0;
+}
+
+static int nuc900_dma_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+	unsigned long flags, val, stype = SUBSTREAM_TYPE(substream);;
+
+	spin_lock_irqsave(&nuc900_audio->lock, flags);
+
+	nuc900_update_dma_register(substream,
+		nuc900_audio->dma_addr[stype], nuc900_audio->buffersize[stype]);
+
+	val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
+
+	switch (runtime->channels) {
+	case 1:
+		if (PCM_TX == stype) {
+			val &= ~(PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
+			val |= PLAY_RIGHT_CHNNEL;
+		} else {
+			val &= ~(RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
+			val |= RECORD_RIGHT_CHNNEL;
+		}
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+		break;
+	case 2:
+		if (PCM_TX == stype)
+			val |= (PLAY_LEFT_CHNNEL | PLAY_RIGHT_CHNNEL);
+		else
+			val |= (RECORD_LEFT_CHNNEL | RECORD_RIGHT_CHNNEL);
+		AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);
+		break;
+	default:
+		return -EINVAL;
+	}
+	spin_unlock_irqrestore(&nuc900_audio->lock, flags);
+	return 0;
+}
+
+static int nuc900_dma_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		nuc900_dma_start(substream);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		nuc900_dma_stop(substream);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+int nuc900_dma_getposition(struct snd_pcm_substream *substream,
+					dma_addr_t *src, dma_addr_t *dst)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+
+	if (src != NULL)
+		*src = AUDIO_READ(nuc900_audio->mmio + ACTL_PDSTC);
+
+	if (dst != NULL)
+		*dst = AUDIO_READ(nuc900_audio->mmio + ACTL_RDSTC);
+
+	return 0;
+}
+
+static snd_pcm_uframes_t nuc900_dma_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	dma_addr_t src, dst;
+	unsigned long res;
+
+	nuc900_dma_getposition(substream, &src, &dst);
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		res = dst - runtime->dma_addr;
+	else
+		res = src - runtime->dma_addr;
+
+	return bytes_to_frames(substream->runtime, res);
+}
+
+static int nuc900_dma_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio;
+
+	snd_soc_set_runtime_hwparams(substream, &nuc900_pcm_hardware);
+
+	nuc900_audio = nuc900_ac97_data;
+
+	if (request_irq(nuc900_audio->irq_num, nuc900_dma_interrupt,
+			IRQF_DISABLED, "nuc900-dma", substream))
+		return -EBUSY;
+
+	runtime->private_data = nuc900_audio;
+
+	return 0;
+}
+
+static int nuc900_dma_close(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct nuc900_audio *nuc900_audio = runtime->private_data;
+
+	free_irq(nuc900_audio->irq_num, substream);
+
+	return 0;
+}
+
+static int nuc900_dma_mmap(struct snd_pcm_substream *substream,
+	struct vm_area_struct *vma)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+
+	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
+					runtime->dma_area,
+					runtime->dma_addr,
+					runtime->dma_bytes);
+}
+
+static struct snd_pcm_ops nuc900_dma_ops = {
+	.open		= nuc900_dma_open,
+	.close		= nuc900_dma_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= nuc900_dma_hw_params,
+	.hw_free	= nuc900_dma_hw_free,
+	.prepare	= nuc900_dma_prepare,
+	.trigger	= nuc900_dma_trigger,
+	.pointer	= nuc900_dma_pointer,
+	.mmap		= nuc900_dma_mmap,
+};
+
+static void nuc900_dma_free_dma_buffers(struct snd_pcm *pcm)
+{
+	snd_pcm_lib_preallocate_free_for_all(pcm);
+}
+
+static u64 nuc900_pcm_dmamask = DMA_BIT_MASK(32);
+static int nuc900_dma_new(struct snd_card *card,
+	struct snd_soc_dai *dai, struct snd_pcm *pcm)
+{
+	if (!card->dev->dma_mask)
+		card->dev->dma_mask = &nuc900_pcm_dmamask;
+	if (!card->dev->coherent_dma_mask)
+		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
+		card->dev, 4 * 1024, (4 * 1024) - 1);
+
+	return 0;
+}
+
+struct snd_soc_platform nuc900_soc_platform = {
+	.name		= "nuc900-dma",
+	.pcm_ops	= &nuc900_dma_ops,
+	.pcm_new	= nuc900_dma_new,
+	.pcm_free	= nuc900_dma_free_dma_buffers,
+}
+EXPORT_SYMBOL_GPL(nuc900_soc_platform);
+
+static int __init nuc900_soc_platform_init(void)
+{
+	return snd_soc_register_platform(&nuc900_soc_platform);
+}
+
+static void __exit nuc900_soc_platform_exit(void)
+{
+	snd_soc_unregister_platform(&nuc900_soc_platform);
+}
+
+module_init(nuc900_soc_platform_init);
+module_exit(nuc900_soc_platform_exit);
+
+MODULE_AUTHOR("Wan ZongShun, <mcuos.com@gmail.com>");
+MODULE_DESCRIPTION("nuc900 Audio DMA module");
+MODULE_LICENSE("GPL");