ASoC: Add driver for s6000 I2S interface

This patch adds a driver for the I2S interface found on Stretch s6000
family processors.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/s6000/s6000-i2s.c b/sound/soc/s6000/s6000-i2s.c
new file mode 100644
index 0000000..dcc7904
--- /dev/null
+++ b/sound/soc/s6000/s6000-i2s.c
@@ -0,0 +1,629 @@
+/*
+ * ALSA SoC I2S Audio Layer for the Stretch S6000 family
+ *
+ * Author:      Daniel Gloeckner, <dg@emlix.com>
+ * Copyright:   (C) 2009 emlix GmbH <info@emlix.com>
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+
+#include "s6000-i2s.h"
+#include "s6000-pcm.h"
+
+struct s6000_i2s_dev {
+	dma_addr_t sifbase;
+	u8 __iomem *scbbase;
+	unsigned int wide;
+	unsigned int channel_in;
+	unsigned int channel_out;
+	unsigned int lines_in;
+	unsigned int lines_out;
+	struct s6000_pcm_dma_params dma_params;
+};
+
+#define S6_I2S_INTERRUPT_STATUS	0x00
+#define   S6_I2S_INT_OVERRUN	1
+#define   S6_I2S_INT_UNDERRUN	2
+#define   S6_I2S_INT_ALIGNMENT	4
+#define S6_I2S_INTERRUPT_ENABLE	0x04
+#define S6_I2S_INTERRUPT_RAW	0x08
+#define S6_I2S_INTERRUPT_CLEAR	0x0C
+#define S6_I2S_INTERRUPT_SET	0x10
+#define S6_I2S_MODE		0x20
+#define   S6_I2S_DUAL		0
+#define   S6_I2S_WIDE		1
+#define S6_I2S_TX_DEFAULT	0x24
+#define S6_I2S_DATA_CFG(c)	(0x40 + 0x10 * (c))
+#define   S6_I2S_IN		0
+#define   S6_I2S_OUT		1
+#define   S6_I2S_UNUSED		2
+#define S6_I2S_INTERFACE_CFG(c)	(0x44 + 0x10 * (c))
+#define   S6_I2S_DIV_MASK	0x001fff
+#define   S6_I2S_16BIT		0x000000
+#define   S6_I2S_20BIT		0x002000
+#define   S6_I2S_24BIT		0x004000
+#define   S6_I2S_32BIT		0x006000
+#define   S6_I2S_BITS_MASK	0x006000
+#define   S6_I2S_MEM_16BIT	0x000000
+#define   S6_I2S_MEM_32BIT	0x008000
+#define   S6_I2S_MEM_MASK	0x008000
+#define   S6_I2S_CHANNELS_SHIFT	16
+#define   S6_I2S_CHANNELS_MASK	0x030000
+#define   S6_I2S_SCK_IN		0x000000
+#define   S6_I2S_SCK_OUT	0x040000
+#define   S6_I2S_SCK_DIR	0x040000
+#define   S6_I2S_WS_IN		0x000000
+#define   S6_I2S_WS_OUT		0x080000
+#define   S6_I2S_WS_DIR		0x080000
+#define   S6_I2S_LEFT_FIRST	0x000000
+#define   S6_I2S_RIGHT_FIRST	0x100000
+#define   S6_I2S_FIRST		0x100000
+#define   S6_I2S_CUR_SCK	0x200000
+#define   S6_I2S_CUR_WS		0x400000
+#define S6_I2S_ENABLE(c)	(0x48 + 0x10 * (c))
+#define   S6_I2S_DISABLE_IF	0x02
+#define   S6_I2S_ENABLE_IF	0x03
+#define   S6_I2S_IS_BUSY	0x04
+#define   S6_I2S_DMA_ACTIVE	0x08
+#define   S6_I2S_IS_ENABLED	0x10
+
+#define S6_I2S_NUM_LINES	4
+
+#define S6_I2S_SIF_PORT0	0x0000000
+#define S6_I2S_SIF_PORT1	0x0000080 /* docs say 0x0000010 */
+
+static inline void s6_i2s_write_reg(struct s6000_i2s_dev *dev, int reg, u32 val)
+{
+	writel(val, dev->scbbase + reg);
+}
+
+static inline u32 s6_i2s_read_reg(struct s6000_i2s_dev *dev, int reg)
+{
+	return readl(dev->scbbase + reg);
+}
+
+static inline void s6_i2s_mod_reg(struct s6000_i2s_dev *dev, int reg,
+				  u32 mask, u32 val)
+{
+	val ^= s6_i2s_read_reg(dev, reg) & ~mask;
+	s6_i2s_write_reg(dev, reg, val);
+}
+
+static void s6000_i2s_start_channel(struct s6000_i2s_dev *dev, int channel)
+{
+	int i, j, cur, prev;
+
+	/*
+	 * Wait for WCLK to toggle 5 times before enabling the channel
+	 * s6000 Family Datasheet 3.6.4:
+	 *   "At least two cycles of WS must occur between commands
+	 *    to disable or enable the interface"
+	 */
+	j = 0;
+	prev = ~S6_I2S_CUR_WS;
+	for (i = 1000000; --i && j < 6; ) {
+		cur = s6_i2s_read_reg(dev, S6_I2S_INTERFACE_CFG(channel))
+		       & S6_I2S_CUR_WS;
+		if (prev != cur) {
+			prev = cur;
+			j++;
+		}
+	}
+	if (j < 6)
+		printk(KERN_WARNING "s6000-i2s: timeout waiting for WCLK\n");
+
+	s6_i2s_write_reg(dev, S6_I2S_ENABLE(channel), S6_I2S_ENABLE_IF);
+}
+
+static void s6000_i2s_stop_channel(struct s6000_i2s_dev *dev, int channel)
+{
+	s6_i2s_write_reg(dev, S6_I2S_ENABLE(channel), S6_I2S_DISABLE_IF);
+}
+
+static void s6000_i2s_start(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct s6000_i2s_dev *dev = rtd->dai->cpu_dai->private_data;
+	int channel;
+
+	channel = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+			dev->channel_out : dev->channel_in;
+
+	s6000_i2s_start_channel(dev, channel);
+}
+
+static void s6000_i2s_stop(struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct s6000_i2s_dev *dev = rtd->dai->cpu_dai->private_data;
+	int channel;
+
+	channel = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+			dev->channel_out : dev->channel_in;
+
+	s6000_i2s_stop_channel(dev, channel);
+}
+
+static int s6000_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
+			     int after)
+{
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if ((substream->stream == SNDRV_PCM_STREAM_CAPTURE) ^ !after)
+			s6000_i2s_start(substream);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (!after)
+			s6000_i2s_stop(substream);
+	}
+	return 0;
+}
+
+static unsigned int s6000_i2s_int_sources(struct s6000_i2s_dev *dev)
+{
+	unsigned int pending;
+	pending = s6_i2s_read_reg(dev, S6_I2S_INTERRUPT_RAW);
+	pending &= S6_I2S_INT_ALIGNMENT |
+		   S6_I2S_INT_UNDERRUN |
+		   S6_I2S_INT_OVERRUN;
+	s6_i2s_write_reg(dev, S6_I2S_INTERRUPT_CLEAR, pending);
+
+	return pending;
+}
+
+static unsigned int s6000_i2s_check_xrun(struct snd_soc_dai *cpu_dai)
+{
+	struct s6000_i2s_dev *dev = cpu_dai->private_data;
+	unsigned int errors;
+	unsigned int ret;
+
+	errors = s6000_i2s_int_sources(dev);
+	if (likely(!errors))
+		return 0;
+
+	ret = 0;
+	if (errors & S6_I2S_INT_ALIGNMENT)
+		printk(KERN_ERR "s6000-i2s: WCLK misaligned\n");
+	if (errors & S6_I2S_INT_UNDERRUN)
+		ret |= 1 << SNDRV_PCM_STREAM_PLAYBACK;
+	if (errors & S6_I2S_INT_OVERRUN)
+		ret |= 1 << SNDRV_PCM_STREAM_CAPTURE;
+	return ret;
+}
+
+static void s6000_i2s_wait_disabled(struct s6000_i2s_dev *dev)
+{
+	int channel;
+	int n = 50;
+	for (channel = 0; channel < 2; channel++) {
+		while (--n >= 0) {
+			int v = s6_i2s_read_reg(dev, S6_I2S_ENABLE(channel));
+			if ((v & S6_I2S_IS_ENABLED)
+			    || !(v & (S6_I2S_DMA_ACTIVE | S6_I2S_IS_BUSY)))
+				break;
+			udelay(20);
+		}
+	}
+	if (n < 0)
+		printk(KERN_WARNING "s6000-i2s: timeout disabling interfaces");
+}
+
+static int s6000_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
+				   unsigned int fmt)
+{
+	struct s6000_i2s_dev *dev = cpu_dai->private_data;
+	u32 w;
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		w = S6_I2S_SCK_IN | S6_I2S_WS_IN;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFM:
+		w = S6_I2S_SCK_OUT | S6_I2S_WS_IN;
+		break;
+	case SND_SOC_DAIFMT_CBM_CFS:
+		w = S6_I2S_SCK_IN | S6_I2S_WS_OUT;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		w = S6_I2S_SCK_OUT | S6_I2S_WS_OUT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_IB_IF:
+		w |= S6_I2S_LEFT_FIRST;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		w |= S6_I2S_RIGHT_FIRST;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	s6_i2s_mod_reg(dev, S6_I2S_INTERFACE_CFG(0),
+		       S6_I2S_FIRST | S6_I2S_WS_DIR | S6_I2S_SCK_DIR, w);
+	s6_i2s_mod_reg(dev, S6_I2S_INTERFACE_CFG(1),
+		       S6_I2S_FIRST | S6_I2S_WS_DIR | S6_I2S_SCK_DIR, w);
+
+	return 0;
+}
+
+static int s6000_i2s_set_clkdiv(struct snd_soc_dai *dai, int div_id, int div)
+{
+	struct s6000_i2s_dev *dev = dai->private_data;
+
+	if (!div || (div & 1) || div > (S6_I2S_DIV_MASK + 1) * 2)
+		return -EINVAL;
+
+	s6_i2s_mod_reg(dev, S6_I2S_INTERFACE_CFG(div_id),
+		       S6_I2S_DIV_MASK, div / 2 - 1);
+	return 0;
+}
+
+static int s6000_i2s_hw_params(struct snd_pcm_substream *substream,
+			       struct snd_pcm_hw_params *params,
+			       struct snd_soc_dai *dai)
+{
+	struct s6000_i2s_dev *dev = dai->private_data;
+	int interf;
+	u32 w = 0;
+
+	if (dev->wide)
+		interf = 0;
+	else {
+		w |= (((params_channels(params) - 2) / 2)
+		      << S6_I2S_CHANNELS_SHIFT) & S6_I2S_CHANNELS_MASK;
+		interf = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+				? dev->channel_out : dev->channel_in;
+	}
+
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		w |= S6_I2S_16BIT | S6_I2S_MEM_16BIT;
+		break;
+	case SNDRV_PCM_FORMAT_S32_LE:
+		w |= S6_I2S_32BIT | S6_I2S_MEM_32BIT;
+		break;
+	default:
+		printk(KERN_WARNING "s6000-i2s: unsupported PCM format %x\n",
+		       params_format(params));
+		return -EINVAL;
+	}
+
+	if (s6_i2s_read_reg(dev, S6_I2S_INTERFACE_CFG(interf))
+	     & S6_I2S_IS_ENABLED) {
+		printk(KERN_ERR "s6000-i2s: interface already enabled\n");
+		return -EBUSY;
+	}
+
+	s6_i2s_mod_reg(dev, S6_I2S_INTERFACE_CFG(interf),
+		       S6_I2S_CHANNELS_MASK|S6_I2S_MEM_MASK|S6_I2S_BITS_MASK,
+		       w);
+
+	return 0;
+}
+
+static int s6000_i2s_dai_probe(struct platform_device *pdev,
+			       struct snd_soc_dai *dai)
+{
+	struct s6000_i2s_dev *dev = dai->private_data;
+	struct s6000_snd_platform_data *pdata = pdev->dev.platform_data;
+
+	if (!pdata)
+		return -EINVAL;
+
+	dev->wide = pdata->wide;
+	dev->channel_in = pdata->channel_in;
+	dev->channel_out = pdata->channel_out;
+	dev->lines_in = pdata->lines_in;
+	dev->lines_out = pdata->lines_out;
+
+	s6_i2s_write_reg(dev, S6_I2S_MODE,
+			 dev->wide ? S6_I2S_WIDE : S6_I2S_DUAL);
+
+	if (dev->wide) {
+		int i;
+
+		if (dev->lines_in + dev->lines_out > S6_I2S_NUM_LINES)
+			return -EINVAL;
+
+		dev->channel_in = 0;
+		dev->channel_out = 1;
+		dai->capture.channels_min = 2 * dev->lines_in;
+		dai->capture.channels_max = dai->capture.channels_min;
+		dai->playback.channels_min = 2 * dev->lines_out;
+		dai->playback.channels_max = dai->playback.channels_min;
+
+		for (i = 0; i < dev->lines_out; i++)
+			s6_i2s_write_reg(dev, S6_I2S_DATA_CFG(i), S6_I2S_OUT);
+
+		for (; i < S6_I2S_NUM_LINES - dev->lines_in; i++)
+			s6_i2s_write_reg(dev, S6_I2S_DATA_CFG(i),
+					 S6_I2S_UNUSED);
+
+		for (; i < S6_I2S_NUM_LINES; i++)
+			s6_i2s_write_reg(dev, S6_I2S_DATA_CFG(i), S6_I2S_IN);
+	} else {
+		unsigned int cfg[2] = {S6_I2S_UNUSED, S6_I2S_UNUSED};
+
+		if (dev->lines_in > 1 || dev->lines_out > 1)
+			return -EINVAL;
+
+		dai->capture.channels_min = 2 * dev->lines_in;
+		dai->capture.channels_max = 8 * dev->lines_in;
+		dai->playback.channels_min = 2 * dev->lines_out;
+		dai->playback.channels_max = 8 * dev->lines_out;
+
+		if (dev->lines_in)
+			cfg[dev->channel_in] = S6_I2S_IN;
+		if (dev->lines_out)
+			cfg[dev->channel_out] = S6_I2S_OUT;
+
+		s6_i2s_write_reg(dev, S6_I2S_DATA_CFG(0), cfg[0]);
+		s6_i2s_write_reg(dev, S6_I2S_DATA_CFG(1), cfg[1]);
+	}
+
+	if (dev->lines_out) {
+		if (dev->lines_in) {
+			if (!dev->dma_params.dma_out)
+				return -ENODEV;
+		} else {
+			dev->dma_params.dma_out = dev->dma_params.dma_in;
+			dev->dma_params.dma_in = 0;
+		}
+	}
+	dev->dma_params.sif_in = dev->sifbase + (dev->channel_in ?
+					S6_I2S_SIF_PORT1 : S6_I2S_SIF_PORT0);
+	dev->dma_params.sif_out = dev->sifbase + (dev->channel_out ?
+					S6_I2S_SIF_PORT1 : S6_I2S_SIF_PORT0);
+	dev->dma_params.same_rate = pdata->same_rate | pdata->wide;
+	return 0;
+}
+
+#define S6000_I2S_RATES	(SNDRV_PCM_RATE_CONTINUOUS | SNDRV_PCM_RATE_5512 | \
+			 SNDRV_PCM_RATE_8000_192000)
+#define S6000_I2S_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE)
+
+static struct snd_soc_dai_ops s6000_i2s_dai_ops = {
+	.set_fmt = s6000_i2s_set_dai_fmt,
+	.set_clkdiv = s6000_i2s_set_clkdiv,
+	.hw_params = s6000_i2s_hw_params,
+};
+
+struct snd_soc_dai s6000_i2s_dai = {
+	.name = "s6000-i2s",
+	.id = 0,
+	.probe = s6000_i2s_dai_probe,
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 8,
+		.formats = S6000_I2S_FORMATS,
+		.rates = S6000_I2S_RATES,
+		.rate_min = 0,
+		.rate_max = 1562500,
+	},
+	.capture = {
+		.channels_min = 2,
+		.channels_max = 8,
+		.formats = S6000_I2S_FORMATS,
+		.rates = S6000_I2S_RATES,
+		.rate_min = 0,
+		.rate_max = 1562500,
+	},
+	.ops = &s6000_i2s_dai_ops,
+}
+EXPORT_SYMBOL_GPL(s6000_i2s_dai);
+
+static int __devinit s6000_i2s_probe(struct platform_device *pdev)
+{
+	struct s6000_i2s_dev *dev;
+	struct resource *scbmem, *sifmem, *region, *dma1, *dma2;
+	u8 __iomem *mmio;
+	int ret;
+
+	scbmem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!scbmem) {
+		dev_err(&pdev->dev, "no mem resource?\n");
+		ret = -ENODEV;
+		goto err_release_none;
+	}
+
+	region = request_mem_region(scbmem->start,
+				    scbmem->end - scbmem->start + 1,
+				    pdev->name);
+	if (!region) {
+		dev_err(&pdev->dev, "I2S SCB region already claimed\n");
+		ret = -EBUSY;
+		goto err_release_none;
+	}
+
+	mmio = ioremap(scbmem->start, scbmem->end - scbmem->start + 1);
+	if (!mmio) {
+		dev_err(&pdev->dev, "can't ioremap SCB region\n");
+		ret = -ENOMEM;
+		goto err_release_scb;
+	}
+
+	sifmem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!sifmem) {
+		dev_err(&pdev->dev, "no second mem resource?\n");
+		ret = -ENODEV;
+		goto err_release_map;
+	}
+
+	region = request_mem_region(sifmem->start,
+				    sifmem->end - sifmem->start + 1,
+				    pdev->name);
+	if (!region) {
+		dev_err(&pdev->dev, "I2S SIF region already claimed\n");
+		ret = -EBUSY;
+		goto err_release_map;
+	}
+
+	dma1 = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	if (!dma1) {
+		dev_err(&pdev->dev, "no dma resource?\n");
+		ret = -ENODEV;
+		goto err_release_sif;
+	}
+
+	region = request_mem_region(dma1->start, dma1->end - dma1->start + 1,
+				    pdev->name);
+	if (!region) {
+		dev_err(&pdev->dev, "I2S DMA region already claimed\n");
+		ret = -EBUSY;
+		goto err_release_sif;
+	}
+
+	dma2 = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+	if (dma2) {
+		region = request_mem_region(dma2->start,
+					    dma2->end - dma2->start + 1,
+					    pdev->name);
+		if (!region) {
+			dev_err(&pdev->dev,
+				"I2S DMA region already claimed\n");
+			ret = -EBUSY;
+			goto err_release_dma1;
+		}
+	}
+
+	dev = kzalloc(sizeof(struct s6000_i2s_dev), GFP_KERNEL);
+	if (!dev) {
+		ret = -ENOMEM;
+		goto err_release_dma2;
+	}
+
+	s6000_i2s_dai.dev = &pdev->dev;
+	s6000_i2s_dai.private_data = dev;
+	s6000_i2s_dai.dma_data = &dev->dma_params;
+
+	dev->sifbase = sifmem->start;
+	dev->scbbase = mmio;
+
+	s6_i2s_write_reg(dev, S6_I2S_INTERRUPT_ENABLE, 0);
+	s6_i2s_write_reg(dev, S6_I2S_INTERRUPT_CLEAR,
+			 S6_I2S_INT_ALIGNMENT |
+			 S6_I2S_INT_UNDERRUN |
+			 S6_I2S_INT_OVERRUN);
+
+	s6000_i2s_stop_channel(dev, 0);
+	s6000_i2s_stop_channel(dev, 1);
+	s6000_i2s_wait_disabled(dev);
+
+	dev->dma_params.check_xrun = s6000_i2s_check_xrun;
+	dev->dma_params.trigger = s6000_i2s_trigger;
+	dev->dma_params.dma_in = dma1->start;
+	dev->dma_params.dma_out = dma2 ? dma2->start : 0;
+	dev->dma_params.irq = platform_get_irq(pdev, 0);
+	if (dev->dma_params.irq < 0) {
+		dev_err(&pdev->dev, "no irq resource?\n");
+		ret = -ENODEV;
+		goto err_release_dev;
+	}
+
+	s6_i2s_write_reg(dev, S6_I2S_INTERRUPT_ENABLE,
+			 S6_I2S_INT_ALIGNMENT |
+			 S6_I2S_INT_UNDERRUN |
+			 S6_I2S_INT_OVERRUN);
+
+	ret = snd_soc_register_dai(&s6000_i2s_dai);
+	if (ret)
+		goto err_release_dev;
+
+	return 0;
+
+err_release_dev:
+	kfree(dev);
+err_release_dma2:
+	if (dma2)
+		release_mem_region(dma2->start, dma2->end - dma2->start + 1);
+err_release_dma1:
+	release_mem_region(dma1->start, dma1->end - dma1->start + 1);
+err_release_sif:
+	release_mem_region(sifmem->start, (sifmem->end - sifmem->start) + 1);
+err_release_map:
+	iounmap(mmio);
+err_release_scb:
+	release_mem_region(scbmem->start, (scbmem->end - scbmem->start) + 1);
+err_release_none:
+	return ret;
+}
+
+static void __devexit s6000_i2s_remove(struct platform_device *pdev)
+{
+	struct s6000_i2s_dev *dev = s6000_i2s_dai.private_data;
+	struct resource *region;
+	void __iomem *mmio = dev->scbbase;
+
+	snd_soc_unregister_dai(&s6000_i2s_dai);
+
+	s6000_i2s_stop_channel(dev, 0);
+	s6000_i2s_stop_channel(dev, 1);
+
+	s6_i2s_write_reg(dev, S6_I2S_INTERRUPT_ENABLE, 0);
+	s6000_i2s_dai.private_data = 0;
+	kfree(dev);
+
+	region = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	release_mem_region(region->start, region->end - region->start + 1);
+
+	region = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+	if (region)
+		release_mem_region(region->start,
+				   region->end - region->start + 1);
+
+	region = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(region->start, (region->end - region->start) + 1);
+
+	iounmap(mmio);
+	region = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	release_mem_region(region->start, (region->end - region->start) + 1);
+}
+
+static struct platform_driver s6000_i2s_driver = {
+	.probe  = s6000_i2s_probe,
+	.remove = __devexit_p(s6000_i2s_remove),
+	.driver = {
+		.name   = "s6000-i2s",
+		.owner  = THIS_MODULE,
+	},
+};
+
+static int __init s6000_i2s_init(void)
+{
+	return platform_driver_register(&s6000_i2s_driver);
+}
+module_init(s6000_i2s_init);
+
+static void __exit s6000_i2s_exit(void)
+{
+	platform_driver_unregister(&s6000_i2s_driver);
+}
+module_exit(s6000_i2s_exit);
+
+MODULE_AUTHOR("Daniel Gloeckner");
+MODULE_DESCRIPTION("Stretch s6000 family I2S SoC Interface");
+MODULE_LICENSE("GPL");