[ALSA] ASoC: S3C2412 IIS driver

S3C2412 SoC IIS support for ALSA/ASoC

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

4 files changed, 724 insertions, 0 deletions

diff --git a/sound/soc/s3c24xx/Kconfig b/sound/soc/s3c24xx/Kconfig
index 14def2e5ada..1f6dbfc4caa 100644
--- a/sound/soc/s3c24xx/Kconfig
+++ b/sound/soc/s3c24xx/Kconfig
@@ -10,6 +10,9 @@ config SND_S3C24XX_SOC
 config SND_S3C24XX_SOC_I2S
 	tristate
 
+config SND_S3C2412_SOC_I2S
+	tristate
+
 config SND_S3C2443_SOC_AC97
 	tristate
 	select AC97_BUS
diff --git a/sound/soc/s3c24xx/Makefile b/sound/soc/s3c24xx/Makefile
index 94719196167..0aa5fb0b970 100644
--- a/sound/soc/s3c24xx/Makefile
+++ b/sound/soc/s3c24xx/Makefile
@@ -1,11 +1,13 @@
 # S3c24XX Platform Support
 snd-soc-s3c24xx-objs := s3c24xx-pcm.o
 snd-soc-s3c24xx-i2s-objs := s3c24xx-i2s.o
+snd-soc-s3c2412-i2s-objs := s3c2412-i2s.o
 snd-soc-s3c2443-ac97-objs := s3c2443-ac97.o
 
 obj-$(CONFIG_SND_S3C24XX_SOC) += snd-soc-s3c24xx.o
 obj-$(CONFIG_SND_S3C24XX_SOC_I2S) += snd-soc-s3c24xx-i2s.o
 obj-$(CONFIG_SND_S3C2443_SOC_AC97) += snd-soc-s3c2443-ac97.o
+obj-$(CONFIG_SND_S3C2412_SOC_I2S) += snd-soc-s3c2412-i2s.o
 
 # S3C24XX Machine Support
 snd-soc-neo1973-wm8753-objs := neo1973_wm8753.o
diff --git a/sound/soc/s3c24xx/s3c2412-i2s.c b/sound/soc/s3c24xx/s3c2412-i2s.c
new file mode 100644
index 00000000000..b10f7ffa942
--- /dev/null
+++ b/sound/soc/s3c24xx/s3c2412-i2s.c
@@ -0,0 +1,681 @@
+/* sound/soc/s3c24xx/s3c2412-i2s.c
+ *
+ * ALSA Soc Audio Layer - S3C2412 I2S driver
+ *
+ * Copyright (c) 2006 Wolfson Microelectronics PLC.
+ *	Graeme Gregory graeme.gregory@wolfsonmicro.com
+ *	linux@wolfsonmicro.com
+ *
+ * Copyright (c) 2007, 2004-2005 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * 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;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/kernel.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <asm/hardware.h>
+
+#include <linux/io.h>
+#include <asm/dma.h>
+
+#include <asm/plat-s3c24xx/regs-s3c2412-iis.h>
+
+#include <asm/arch/regs-gpio.h>
+#include <asm/arch/audio.h>
+#include <asm/arch/dma.h>
+
+#include "s3c24xx-pcm.h"
+#include "s3c2412-i2s.h"
+
+#define S3C2412_I2S_DEBUG 0
+#define S3C2412_I2S_DEBUG_CON 0
+
+#if S3C2412_I2S_DEBUG
+#define DBG(x...) printk(KERN_INFO x)
+#else
+#define DBG(x...) do { } while (0)
+#endif
+
+static struct s3c2410_dma_client s3c2412_dma_client_out = {
+	.name		= "I2S PCM Stereo out"
+};
+
+static struct s3c2410_dma_client s3c2412_dma_client_in = {
+	.name		= "I2S PCM Stereo in"
+};
+
+static struct s3c24xx_pcm_dma_params s3c2412_i2s_pcm_stereo_out = {
+	.client		= &s3c2412_dma_client_out,
+	.channel	= DMACH_I2S_OUT,
+	.dma_addr	= S3C2410_PA_IIS + S3C2412_IISTXD,
+	.dma_size	= 4,
+};
+
+static struct s3c24xx_pcm_dma_params s3c2412_i2s_pcm_stereo_in = {
+	.client		= &s3c2412_dma_client_in,
+	.channel	= DMACH_I2S_IN,
+	.dma_addr	= S3C2410_PA_IIS + S3C2412_IISRXD,
+	.dma_size	= 4,
+};
+
+struct s3c2412_i2s_info {
+	struct device	*dev;
+	void __iomem	*regs;
+	struct clk	*iis_clk;
+	struct clk	*iis_pclk;
+	struct clk	*iis_cclk;
+};
+
+static struct s3c2412_i2s_info s3c2412_i2s;
+
+#define bit_set(v, b) (((v) & (b)) ? 1 : 0)
+
+#if S3C2412_I2S_DEBUG_CON
+static void dbg_showcon(const char *fn, u32 con)
+{
+	printk(KERN_DEBUG "%s: LRI=%d, TXFEMPT=%d, RXFEMPT=%d, TXFFULL=%d, RXFFULL=%d\n", fn,
+	       bit_set(con, S3C2412_IISCON_LRINDEX),
+	       bit_set(con, S3C2412_IISCON_TXFIFO_EMPTY),
+	       bit_set(con, S3C2412_IISCON_RXFIFO_EMPTY),
+	       bit_set(con, S3C2412_IISCON_TXFIFO_FULL),
+	       bit_set(con, S3C2412_IISCON_RXFIFO_FULL));
+
+	printk(KERN_DEBUG "%s: PAUSE: TXDMA=%d, RXDMA=%d, TXCH=%d, RXCH=%d\n",
+	       fn,
+	       bit_set(con, S3C2412_IISCON_TXDMA_PAUSE),
+	       bit_set(con, S3C2412_IISCON_RXDMA_PAUSE),
+	       bit_set(con, S3C2412_IISCON_TXCH_PAUSE),
+	       bit_set(con, S3C2412_IISCON_RXCH_PAUSE));
+	printk(KERN_DEBUG "%s: ACTIVE: TXDMA=%d, RXDMA=%d, IIS=%d\n", fn,
+	       bit_set(con, S3C2412_IISCON_TXDMA_ACTIVE),
+	       bit_set(con, S3C2412_IISCON_RXDMA_ACTIVE),
+	       bit_set(con, S3C2412_IISCON_IIS_ACTIVE));
+}
+#else
+static inline void dbg_showcon(const char *fn, u32 con)
+{
+}
+#endif
+
+/* Turn on or off the transmission path. */
+static void s3c2412_snd_txctrl(int on)
+{
+	struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
+	void __iomem *regs = i2s->regs;
+	u32 fic, con, mod;
+
+	DBG("%s(%d)\n", __func__, on);
+
+	fic = readl(regs + S3C2412_IISFIC);
+	con = readl(regs + S3C2412_IISCON);
+	mod = readl(regs + S3C2412_IISMOD);
+
+	DBG("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
+
+	if (on) {
+		con |= S3C2412_IISCON_TXDMA_ACTIVE | S3C2412_IISCON_IIS_ACTIVE;
+		con &= ~S3C2412_IISCON_TXDMA_PAUSE;
+		con &= ~S3C2412_IISCON_TXCH_PAUSE;
+
+		switch (mod & S3C2412_IISMOD_MODE_MASK) {
+		case S3C2412_IISMOD_MODE_TXONLY:
+		case S3C2412_IISMOD_MODE_TXRX:
+			/* do nothing, we are in the right mode */
+			break;
+
+		case S3C2412_IISMOD_MODE_RXONLY:
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			mod |= S3C2412_IISMOD_MODE_TXRX;
+			break;
+
+		default:
+			dev_err(i2s->dev, "TXEN: Invalid MODE in IISMOD\n");
+		}
+
+		writel(con, regs + S3C2412_IISCON);
+		writel(mod, regs + S3C2412_IISMOD);
+	} else {
+		/* Note, we do not have any indication that the FIFO problems
+		 * tha the S3C2410/2440 had apply here, so we should be able
+		 * to disable the DMA and TX without resetting the FIFOS.
+		 */
+
+		con |=  S3C2412_IISCON_TXDMA_PAUSE;
+		con |=  S3C2412_IISCON_TXCH_PAUSE;
+		con &= ~S3C2412_IISCON_TXDMA_ACTIVE;
+
+		switch (mod & S3C2412_IISMOD_MODE_MASK) {
+		case S3C2412_IISMOD_MODE_TXRX:
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			mod |= S3C2412_IISMOD_MODE_RXONLY;
+			break;
+
+		case S3C2412_IISMOD_MODE_TXONLY:
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			con &= ~S3C2412_IISCON_IIS_ACTIVE;
+			break;
+
+		default:
+			dev_err(i2s->dev, "TXDIS: Invalid MODE in IISMOD\n");
+		}
+
+		writel(mod, regs + S3C2412_IISMOD);
+		writel(con, regs + S3C2412_IISCON);
+	}
+
+	fic = readl(regs + S3C2412_IISFIC);
+	dbg_showcon(__func__, con);
+	DBG("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
+}
+
+static void s3c2412_snd_rxctrl(int on)
+{
+	struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
+	void __iomem *regs = i2s->regs;
+	u32 fic, con, mod;
+
+	DBG("%s(%d)\n", __func__, on);
+
+	fic = readl(regs + S3C2412_IISFIC);
+	con = readl(regs + S3C2412_IISCON);
+	mod = readl(regs + S3C2412_IISMOD);
+
+	DBG("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
+
+	if (on) {
+		con |= S3C2412_IISCON_RXDMA_ACTIVE | S3C2412_IISCON_IIS_ACTIVE;
+		con &= ~S3C2412_IISCON_RXDMA_PAUSE;
+		con &= ~S3C2412_IISCON_RXCH_PAUSE;
+
+		switch (mod & S3C2412_IISMOD_MODE_MASK) {
+		case S3C2412_IISMOD_MODE_TXRX:
+		case S3C2412_IISMOD_MODE_RXONLY:
+			/* do nothing, we are in the right mode */
+			break;
+
+		case S3C2412_IISMOD_MODE_TXONLY:
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			mod |= S3C2412_IISMOD_MODE_TXRX;
+			break;
+
+		default:
+			dev_err(i2s->dev, "RXEN: Invalid MODE in IISMOD\n");
+		}
+
+		writel(mod, regs + S3C2412_IISMOD);
+		writel(con, regs + S3C2412_IISCON);
+	} else {
+		/* See txctrl notes on FIFOs. */
+
+		con &= ~S3C2412_IISCON_RXDMA_ACTIVE;
+		con |=  S3C2412_IISCON_RXDMA_PAUSE;
+		con |=  S3C2412_IISCON_RXCH_PAUSE;
+
+		switch (mod & S3C2412_IISMOD_MODE_MASK) {
+		case S3C2412_IISMOD_MODE_RXONLY:
+			con &= ~S3C2412_IISCON_IIS_ACTIVE;
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			break;
+
+		case S3C2412_IISMOD_MODE_TXRX:
+			mod &= ~S3C2412_IISMOD_MODE_MASK;
+			mod |= S3C2412_IISMOD_MODE_TXONLY;
+			break;
+
+		default:
+			dev_err(i2s->dev, "RXEN: Invalid MODE in IISMOD\n");
+		}
+
+		writel(con, regs + S3C2412_IISCON);
+		writel(mod, regs + S3C2412_IISMOD);
+	}
+
+	fic = readl(regs + S3C2412_IISFIC);
+	DBG("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
+}
+
+
+/*
+ * Wait for the LR signal to allow synchronisation to the L/R clock
+ * from the codec. May only be needed for slave mode.
+ */
+static int s3c2412_snd_lrsync(void)
+{
+	u32 iiscon;
+	unsigned long timeout = jiffies + msecs_to_jiffies(5);
+
+	DBG("Entered %s\n", __func__);
+
+	while (1) {
+		iiscon = readl(s3c2412_i2s.regs + S3C2412_IISCON);
+		if (iiscon & S3C2412_IISCON_LRINDEX)
+			break;
+
+		if (timeout < jiffies) {
+			printk(KERN_ERR "%s: timeout\n", __func__);
+			return -ETIMEDOUT;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Check whether CPU is the master or slave
+ */
+static inline int s3c2412_snd_is_clkmaster(void)
+{
+	u32 iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
+
+	DBG("Entered %s\n", __func__);
+
+	iismod &= S3C2412_IISMOD_MASTER_MASK;
+	return !(iismod == S3C2412_IISMOD_SLAVE);
+}
+
+/*
+ * Set S3C2412 I2S DAI format
+ */
+static int s3c2412_i2s_set_fmt(struct snd_soc_cpu_dai *cpu_dai,
+			       unsigned int fmt)
+{
+	u32 iismod;
+
+
+	DBG("Entered %s\n", __func__);
+
+	iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
+	DBG("hw_params r: IISMOD: %x \n", iismod);
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		iismod &= ~S3C2412_IISMOD_MASTER_MASK;
+		iismod |= S3C2412_IISMOD_SLAVE;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		iismod &= ~S3C2412_IISMOD_MASTER_MASK;
+		iismod |= S3C2412_IISMOD_MASTER_INTERNAL;
+		break;
+	default:
+		DBG("unknwon master/slave format\n");
+		return -EINVAL;
+	}
+
+	iismod &= ~S3C2412_IISMOD_SDF_MASK;
+
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_RIGHT_J:
+		iismod |= S3C2412_IISMOD_SDF_MSB;
+		break;
+	case SND_SOC_DAIFMT_LEFT_J:
+		iismod |= S3C2412_IISMOD_SDF_LSB;
+		break;
+	case SND_SOC_DAIFMT_I2S:
+		iismod |= S3C2412_IISMOD_SDF_IIS;
+		break;
+	default:
+		DBG("Unknown data format\n");
+		return -EINVAL;
+	}
+
+	writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
+	DBG("hw_params w: IISMOD: %x \n", iismod);
+	return 0;
+}
+
+static int s3c2412_i2s_hw_params(struct snd_pcm_substream *substream,
+				 struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	u32 iismod;
+
+	DBG("Entered %s\n", __func__);
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		rtd->dai->cpu_dai->dma_data = &s3c2412_i2s_pcm_stereo_out;
+	else
+		rtd->dai->cpu_dai->dma_data = &s3c2412_i2s_pcm_stereo_in;
+
+	/* Working copies of register */
+	iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
+	DBG("%s: r: IISMOD: %x\n", __func__, iismod);
+
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S8:
+		iismod |= S3C2412_IISMOD_8BIT;
+		break;
+	case SNDRV_PCM_FORMAT_S16_LE:
+		iismod &= ~S3C2412_IISMOD_8BIT;
+		break;
+	}
+
+	writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
+	DBG("%s: w: IISMOD: %x\n", __func__, iismod);
+	return 0;
+}
+
+static int s3c2412_i2s_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	int capture = (substream->stream == SNDRV_PCM_STREAM_CAPTURE);
+	unsigned long irqs;
+	int ret = 0;
+
+	DBG("Entered %s\n", __func__);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		/* On start, ensure that the FIFOs are cleared and reset. */
+
+		writel(capture ? S3C2412_IISFIC_RXFLUSH : S3C2412_IISFIC_TXFLUSH,
+		       s3c2412_i2s.regs + S3C2412_IISFIC);
+
+		/* clear again, just in case */
+		writel(0x0, s3c2412_i2s.regs + S3C2412_IISFIC);
+
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (!s3c2412_snd_is_clkmaster()) {
+			ret = s3c2412_snd_lrsync();
+			if (ret)
+				goto exit_err;
+		}
+
+		local_irq_save(irqs);
+
+		if (capture)
+			s3c2412_snd_rxctrl(1);
+		else
+			s3c2412_snd_txctrl(1);
+
+		local_irq_restore(irqs);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		local_irq_save(irqs);
+
+		if (capture)
+			s3c2412_snd_rxctrl(0);
+		else
+			s3c2412_snd_txctrl(0);
+
+		local_irq_restore(irqs);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+exit_err:
+	return ret;
+}
+
+/* default table of all avaialable root fs divisors */
+static unsigned int s3c2412_iis_fs[] = { 256, 512, 384, 768, 0 };
+
+int s3c2412_iis_calc_rate(struct s3c2412_rate_calc *info,
+			  unsigned int *fstab,
+			  unsigned int rate, struct clk *clk)
+{
+	unsigned long clkrate = clk_get_rate(clk);
+	unsigned int div;
+	unsigned int fsclk;
+	unsigned int actual;
+	unsigned int fs;
+	unsigned int fsdiv;
+	signed int deviation = 0;
+	unsigned int best_fs = 0;
+	unsigned int best_div = 0;
+	unsigned int best_rate = 0;
+	unsigned int best_deviation = INT_MAX;
+
+
+	if (fstab == NULL)
+		fstab = s3c2412_iis_fs;
+
+	for (fs = 0;; fs++) {
+		fsdiv = s3c2412_iis_fs[fs];
+
+		if (fsdiv == 0)
+			break;
+
+		fsclk = clkrate / fsdiv;
+		div = fsclk / rate;
+
+		if ((fsclk % rate) > (rate / 2))
+			div++;
+
+		if (div <= 1)
+			continue;
+
+		actual = clkrate / (fsdiv * div);
+		deviation = actual - rate;
+
+		printk(KERN_DEBUG "%dfs: div %d => result %d, deviation %d\n",
+		       fsdiv, div, actual, deviation);
+
+		deviation = abs(deviation);
+
+		if (deviation < best_deviation) {
+			best_fs = fsdiv;
+			best_div = div;
+			best_rate = actual;
+			best_deviation = deviation;
+		}
+
+		if (deviation == 0)
+			break;
+	}
+
+	printk(KERN_DEBUG "best: fs=%d, div=%d, rate=%d\n",
+	       best_fs, best_div, best_rate);
+
+	info->fs_div = best_fs;
+	info->clk_div = best_div;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(s3c2412_iis_calc_rate);
+
+/*
+ * Set S3C2412 Clock source
+ */
+static int s3c2412_i2s_set_sysclk(struct snd_soc_cpu_dai *cpu_dai,
+				  int clk_id, unsigned int freq, int dir)
+{
+	u32 iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
+
+	DBG("%s(%p, %d, %u, %d)\n", __func__, cpu_dai, clk_id,
+	    freq, dir);
+
+	switch (clk_id) {
+	case S3C2412_CLKSRC_PCLK:
+		iismod &= ~S3C2412_IISMOD_MASTER_MASK;
+		iismod |= S3C2412_IISMOD_MASTER_INTERNAL;
+		break;
+	case S3C2412_CLKSRC_I2SCLK:
+		iismod &= ~S3C2412_IISMOD_MASTER_MASK;
+		iismod |= S3C2412_IISMOD_MASTER_EXTERNAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
+	return 0;
+}
+
+/*
+ * Set S3C2412 Clock dividers
+ */
+static int s3c2412_i2s_set_clkdiv(struct snd_soc_cpu_dai *cpu_dai,
+				  int div_id, int div)
+{
+	struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
+	u32 reg;
+
+	DBG("%s(%p, %d, %d)\n", __func__, cpu_dai, div_id, div);
+
+	switch (div_id) {
+	case S3C2412_DIV_BCLK:
+		reg = readl(i2s->regs + S3C2412_IISMOD);
+		reg &= ~S3C2412_IISMOD_BCLK_MASK;
+		writel(reg | div, i2s->regs + S3C2412_IISMOD);
+
+		DBG("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
+		break;
+
+	case S3C2412_DIV_RCLK:
+		if (div > 3) {
+			/* convert value to bit field */
+
+			switch (div) {
+			case 256:
+				div = S3C2412_IISMOD_RCLK_256FS;
+				break;
+
+			case 384:
+				div = S3C2412_IISMOD_RCLK_384FS;
+				break;
+
+			case 512:
+				div = S3C2412_IISMOD_RCLK_512FS;
+				break;
+
+			case 768:
+				div = S3C2412_IISMOD_RCLK_768FS;
+				break;
+
+			default:
+				return -EINVAL;
+			}
+		}
+
+		reg = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
+		reg &= ~S3C2412_IISMOD_RCLK_MASK;
+		writel(reg | div, i2s->regs + S3C2412_IISMOD);
+		DBG("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
+		break;
+
+	case S3C2412_DIV_PRESCALER:
+		if (div >= 0) {
+			writel((div << 8) | S3C2412_IISPSR_PSREN,
+			       i2s->regs + S3C2412_IISPSR);
+		} else {
+			writel(0x0, i2s->regs + S3C2412_IISPSR);
+		}
+		DBG("%s: PSR=%08x\n", __func__, readl(i2s->regs + S3C2412_IISPSR));
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+struct clk *s3c2412_get_iisclk(void)
+{
+	return s3c2412_i2s.iis_clk;
+}
+EXPORT_SYMBOL_GPL(s3c2412_get_iisclk);
+
+
+static int s3c2412_i2s_probe(struct platform_device *pdev)
+{
+	DBG("Entered %s\n", __func__);
+
+	s3c2412_i2s.dev = &pdev->dev;
+
+	s3c2412_i2s.regs = ioremap(S3C2410_PA_IIS, 0x100);
+	if (s3c2412_i2s.regs == NULL)
+		return -ENXIO;
+
+	s3c2412_i2s.iis_pclk = clk_get(&pdev->dev, "iis");
+	if (s3c2412_i2s.iis_pclk == NULL) {
+		DBG("failed to get iis_clock\n");
+		iounmap(s3c2412_i2s.regs);
+		return -ENODEV;
+	}
+
+	s3c2412_i2s.iis_cclk = clk_get(&pdev->dev, "i2sclk");
+	if (s3c2412_i2s.iis_cclk == NULL) {
+		DBG("failed to get i2sclk clock\n");
+		iounmap(s3c2412_i2s.regs);
+		return -ENODEV;
+	}
+
+	clk_set_parent(s3c2412_i2s.iis_cclk, clk_get(NULL, "mpll"));
+
+	clk_enable(s3c2412_i2s.iis_pclk);
+	clk_enable(s3c2412_i2s.iis_cclk);
+
+	s3c2412_i2s.iis_clk = s3c2412_i2s.iis_pclk;
+
+	/* Configure the I2S pins in correct mode */
+	s3c2410_gpio_cfgpin(S3C2410_GPE0, S3C2410_GPE0_I2SLRCK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE1, S3C2410_GPE1_I2SSCLK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE2, S3C2410_GPE2_CDCLK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE3, S3C2410_GPE3_I2SSDI);
+	s3c2410_gpio_cfgpin(S3C2410_GPE4, S3C2410_GPE4_I2SSDO);
+
+	s3c2412_snd_txctrl(0);
+	s3c2412_snd_rxctrl(0);
+
+	return 0;
+}
+
+#define S3C2412_I2S_RATES \
+	(SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 | SNDRV_PCM_RATE_16000 | \
+	SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
+	SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000)
+
+struct snd_soc_cpu_dai s3c2412_i2s_dai = {
+	.name	= "s3c2412-i2s",
+	.id	= 0,
+	.type	= SND_SOC_DAI_I2S,
+	.probe	= s3c2412_i2s_probe,
+	.playback = {
+		.channels_min	= 2,
+		.channels_max	= 2,
+		.rates		= S3C2412_I2S_RATES,
+		.formats	= SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.capture = {
+		.channels_min	= 2,
+		.channels_max	= 2,
+		.rates		= S3C2412_I2S_RATES,
+		.formats	= SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.ops = {
+		.trigger	= s3c2412_i2s_trigger,
+		.hw_params	= s3c2412_i2s_hw_params,
+	},
+	.dai_ops = {
+		.set_fmt	= s3c2412_i2s_set_fmt,
+		.set_clkdiv	= s3c2412_i2s_set_clkdiv,
+		.set_sysclk	= s3c2412_i2s_set_sysclk,
+	},
+};
+EXPORT_SYMBOL_GPL(s3c2412_i2s_dai);
+
+/* Module information */
+MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
+MODULE_DESCRIPTION("S3C2412 I2S SoC Interface");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/s3c24xx/s3c2412-i2s.h b/sound/soc/s3c24xx/s3c2412-i2s.h
new file mode 100644
index 00000000000..27f48e1ffa8
--- /dev/null
+++ b/sound/soc/s3c24xx/s3c2412-i2s.h
@@ -0,0 +1,38 @@
+/* sound/soc/s3c24xx/s3c2412-i2s.c
+ *
+ * ALSA Soc Audio Layer - S3C2412 I2S driver
+ *
+ * Copyright (c) 2007 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ *  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;  either version 2 of the  License, or (at your
+ *  option) any later version.
+*/
+
+#ifndef __SND_SOC_S3C24XX_S3C2412_I2S_H
+#define __SND_SOC_S3C24XX_S3C2412_I2S_H __FILE__
+
+#define S3C2412_DIV_BCLK	(1)
+#define S3C2412_DIV_RCLK	(2)
+#define S3C2412_DIV_PRESCALER	(3)
+
+#define S3C2412_CLKSRC_PCLK	(0)
+#define S3C2412_CLKSRC_I2SCLK	(1)
+
+extern struct clk *s3c2412_get_iisclk(void);
+
+extern struct snd_soc_cpu_dai s3c2412_i2s_dai;
+
+struct s3c2412_rate_calc {
+	unsigned int	clk_div;	/* for prescaler */
+	unsigned int	fs_div;		/* for root frame clock */
+};
+
+extern int s3c2412_iis_calc_rate(struct s3c2412_rate_calc *info,
+				 unsigned int *fstab,
+				 unsigned int rate, struct clk *clk);
+
+#endif /* __SND_SOC_S3C24XX_S3C2412_I2S_H */