sound/soc/samsung/spdif.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 //
 // ALSA SoC Audio Layer - Samsung S/PDIF Controller driver
 //
 // Copyright (c) 2010 Samsung Electronics Co. Ltd
 //		http://www.samsung.com/

 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/module.h>

 #include <sound/soc.h>
 #include <sound/pcm_params.h>

 #include <linux/platform_data/asoc-s3c.h>

 #include "dma.h"
 #include "spdif.h"

 /* Registers */
 #define CLKCON				0x00
 #define CON				0x04
 #define BSTAS				0x08
 #define CSTAS				0x0C
 #define DATA_OUTBUF			0x10
 #define DCNT				0x14
 #define BSTAS_S				0x18
 #define DCNT_S				0x1C

 #define CLKCTL_MASK			0x7
 #define CLKCTL_MCLK_EXT			(0x1 << 2)
 #define CLKCTL_PWR_ON			(0x1 << 0)

 #define CON_MASK			0x3ffffff
 #define CON_FIFO_TH_SHIFT		19
 #define CON_FIFO_TH_MASK		(0x7 << 19)
 #define CON_USERDATA_23RDBIT		(0x1 << 12)

 #define CON_SW_RESET			(0x1 << 5)

 #define CON_MCLKDIV_MASK		(0x3 << 3)
 #define CON_MCLKDIV_256FS		(0x0 << 3)
 #define CON_MCLKDIV_384FS		(0x1 << 3)
 #define CON_MCLKDIV_512FS		(0x2 << 3)

 #define CON_PCM_MASK			(0x3 << 1)
 #define CON_PCM_16BIT			(0x0 << 1)
 #define CON_PCM_20BIT			(0x1 << 1)
 #define CON_PCM_24BIT			(0x2 << 1)

 #define CON_PCM_DATA			(0x1 << 0)

 #define CSTAS_MASK			0x3fffffff
 #define CSTAS_SAMP_FREQ_MASK		(0xF << 24)
 #define CSTAS_SAMP_FREQ_44		(0x0 << 24)
 #define CSTAS_SAMP_FREQ_48		(0x2 << 24)
 #define CSTAS_SAMP_FREQ_32		(0x3 << 24)
 #define CSTAS_SAMP_FREQ_96		(0xA << 24)

 #define CSTAS_CATEGORY_MASK		(0xFF << 8)
 #define CSTAS_CATEGORY_CODE_CDP		(0x01 << 8)

 #define CSTAS_NO_COPYRIGHT		(0x1 << 2)

 /**
  * struct samsung_spdif_info - Samsung S/PDIF Controller information
  * @lock: Spin lock for S/PDIF.
  * @dev: The parent device passed to use from the probe.
  * @regs: The pointer to the device register block.
  * @clk_rate: Current clock rate for calcurate ratio.
  * @pclk: The peri-clock pointer for spdif master operation.
  * @sclk: The source clock pointer for making sync signals.
  * @saved_clkcon: Backup clkcon reg. in suspend.
  * @saved_con: Backup con reg. in suspend.
  * @saved_cstas: Backup cstas reg. in suspend.
  * @dma_playback: DMA information for playback channel.
  */
 struct samsung_spdif_info {
 	spinlock_t	lock;
 	struct device	*dev;
 	void __iomem	*regs;
 	unsigned long	clk_rate;
 	struct clk	*pclk;
 	struct clk	*sclk;
 	u32		saved_clkcon;
 	u32		saved_con;
 	u32		saved_cstas;
 	struct snd_dmaengine_dai_dma_data *dma_playback;
 };

 static struct snd_dmaengine_dai_dma_data spdif_stereo_out;
 static struct samsung_spdif_info spdif_info;

 static inline struct samsung_spdif_info
 *component_to_info(struct snd_soc_component *component)
 {
 	return snd_soc_component_get_drvdata(component);
 }

 static inline struct samsung_spdif_info *to_info(struct snd_soc_dai *cpu_dai)
 {
 	return snd_soc_dai_get_drvdata(cpu_dai);
 }

 static void spdif_snd_txctrl(struct samsung_spdif_info *spdif, int on)
 {
 	void __iomem *regs = spdif->regs;
 	u32 clkcon;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;
 	if (on)
 		writel(clkcon | CLKCTL_PWR_ON, regs + CLKCON);
 	else
 		writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
 }

 static int spdif_set_sysclk(struct snd_soc_dai *cpu_dai,
 				int clk_id, unsigned int freq, int dir)
 {
 	struct samsung_spdif_info *spdif = to_info(cpu_dai);
 	u32 clkcon;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	clkcon = readl(spdif->regs + CLKCON);

 	if (clk_id == SND_SOC_SPDIF_INT_MCLK)
 		clkcon &= ~CLKCTL_MCLK_EXT;
 	else
 		clkcon |= CLKCTL_MCLK_EXT;

 	writel(clkcon, spdif->regs + CLKCON);

 	spdif->clk_rate = freq;

 	return 0;
 }

 static int spdif_trigger(struct snd_pcm_substream *substream, int cmd,
 				struct snd_soc_dai *dai)
 {
 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
 	unsigned long flags;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		spin_lock_irqsave(&spdif->lock, flags);
 		spdif_snd_txctrl(spdif, 1);
 		spin_unlock_irqrestore(&spdif->lock, flags);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		spin_lock_irqsave(&spdif->lock, flags);
 		spdif_snd_txctrl(spdif, 0);
 		spin_unlock_irqrestore(&spdif->lock, flags);
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static int spdif_sysclk_ratios[] = {
 	512, 384, 256,
 };

 static int spdif_hw_params(struct snd_pcm_substream *substream,
 				struct snd_pcm_hw_params *params,
 				struct snd_soc_dai *socdai)
 {
 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
 	void __iomem *regs = spdif->regs;
 	struct snd_dmaengine_dai_dma_data *dma_data;
 	u32 con, clkcon, cstas;
 	unsigned long flags;
 	int i, ratio;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		dma_data = spdif->dma_playback;
 	else {
 		dev_err(spdif->dev, "Capture is not supported\n");
 		return -EINVAL;
 	}

 	snd_soc_dai_set_dma_data(asoc_rtd_to_cpu(rtd, 0), substream, dma_data);

 	spin_lock_irqsave(&spdif->lock, flags);

 	con = readl(regs + CON) & CON_MASK;
 	cstas = readl(regs + CSTAS) & CSTAS_MASK;
 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;

 	con &= ~CON_FIFO_TH_MASK;
 	con |= (0x7 << CON_FIFO_TH_SHIFT);
 	con |= CON_USERDATA_23RDBIT;
 	con |= CON_PCM_DATA;

 	con &= ~CON_PCM_MASK;
 	switch (params_width(params)) {
 	case 16:
 		con |= CON_PCM_16BIT;
 		break;
 	default:
 		dev_err(spdif->dev, "Unsupported data size.\n");
 		goto err;
 	}

 	ratio = spdif->clk_rate / params_rate(params);
 	for (i = 0; i < ARRAY_SIZE(spdif_sysclk_ratios); i++)
 		if (ratio == spdif_sysclk_ratios[i])
 			break;
 	if (i == ARRAY_SIZE(spdif_sysclk_ratios)) {
 		dev_err(spdif->dev, "Invalid clock ratio %ld/%d\n",
 				spdif->clk_rate, params_rate(params));
 		goto err;
 	}

 	con &= ~CON_MCLKDIV_MASK;
 	switch (ratio) {
 	case 256:
 		con |= CON_MCLKDIV_256FS;
 		break;
 	case 384:
 		con |= CON_MCLKDIV_384FS;
 		break;
 	case 512:
 		con |= CON_MCLKDIV_512FS;
 		break;
 	}

 	cstas &= ~CSTAS_SAMP_FREQ_MASK;
 	switch (params_rate(params)) {
 	case 44100:
 		cstas |= CSTAS_SAMP_FREQ_44;
 		break;
 	case 48000:
 		cstas |= CSTAS_SAMP_FREQ_48;
 		break;
 	case 32000:
 		cstas |= CSTAS_SAMP_FREQ_32;
 		break;
 	case 96000:
 		cstas |= CSTAS_SAMP_FREQ_96;
 		break;
 	default:
 		dev_err(spdif->dev, "Invalid sampling rate %d\n",
 				params_rate(params));
 		goto err;
 	}

 	cstas &= ~CSTAS_CATEGORY_MASK;
 	cstas |= CSTAS_CATEGORY_CODE_CDP;
 	cstas |= CSTAS_NO_COPYRIGHT;

 	writel(con, regs + CON);
 	writel(cstas, regs + CSTAS);
 	writel(clkcon, regs + CLKCON);

 	spin_unlock_irqrestore(&spdif->lock, flags);

 	return 0;
 err:
 	spin_unlock_irqrestore(&spdif->lock, flags);
 	return -EINVAL;
 }

 static void spdif_shutdown(struct snd_pcm_substream *substream,
 				struct snd_soc_dai *dai)
 {
 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
 	void __iomem *regs = spdif->regs;
 	u32 con, clkcon;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	con = readl(regs + CON) & CON_MASK;
 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;

 	writel(con | CON_SW_RESET, regs + CON);
 	cpu_relax();

 	writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
 }

 #ifdef CONFIG_PM
 static int spdif_suspend(struct snd_soc_component *component)
 {
 	struct samsung_spdif_info *spdif = component_to_info(component);
 	u32 con = spdif->saved_con;

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	spdif->saved_clkcon = readl(spdif->regs	+ CLKCON) & CLKCTL_MASK;
 	spdif->saved_con = readl(spdif->regs + CON) & CON_MASK;
 	spdif->saved_cstas = readl(spdif->regs + CSTAS) & CSTAS_MASK;

 	writel(con | CON_SW_RESET, spdif->regs + CON);
 	cpu_relax();

 	return 0;
 }

 static int spdif_resume(struct snd_soc_component *component)
 {
 	struct samsung_spdif_info *spdif = component_to_info(component);

 	dev_dbg(spdif->dev, "Entered %s\n", __func__);

 	writel(spdif->saved_clkcon, spdif->regs	+ CLKCON);
 	writel(spdif->saved_con, spdif->regs + CON);
 	writel(spdif->saved_cstas, spdif->regs + CSTAS);

 	return 0;
 }
 #else
 #define spdif_suspend NULL
 #define spdif_resume NULL
 #endif

 static const struct snd_soc_dai_ops spdif_dai_ops = {
 	.set_sysclk	= spdif_set_sysclk,
 	.trigger	= spdif_trigger,
 	.hw_params	= spdif_hw_params,
 	.shutdown	= spdif_shutdown,
 };

 static struct snd_soc_dai_driver samsung_spdif_dai = {
 	.name = "samsung-spdif",
 	.playback = {
 		.stream_name = "S/PDIF Playback",
 		.channels_min = 2,
 		.channels_max = 2,
 		.rates = (SNDRV_PCM_RATE_32000 |
 				SNDRV_PCM_RATE_44100 |
 				SNDRV_PCM_RATE_48000 |
 				SNDRV_PCM_RATE_96000),
 		.formats = SNDRV_PCM_FMTBIT_S16_LE, },
 	.ops = &spdif_dai_ops,
 };

 static const struct snd_soc_component_driver samsung_spdif_component = {
 	.name		= "samsung-spdif",
 	.suspend	= spdif_suspend,
 	.resume		= spdif_resume,
 };

 static int spdif_probe(struct platform_device *pdev)
 {
 	struct s3c_audio_pdata *spdif_pdata;
 	struct resource *mem_res;
 	struct samsung_spdif_info *spdif;
 	dma_filter_fn filter;
 	int ret;

 	spdif_pdata = pdev->dev.platform_data;

 	dev_dbg(&pdev->dev, "Entered %s\n", __func__);

 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem_res) {
 		dev_err(&pdev->dev, "Unable to get register resource.\n");
 		return -ENXIO;
 	}

 	if (spdif_pdata && spdif_pdata->cfg_gpio
 			&& spdif_pdata->cfg_gpio(pdev)) {
 		dev_err(&pdev->dev, "Unable to configure GPIO pins\n");
 		return -EINVAL;
 	}

 	spdif = &spdif_info;
 	spdif->dev = &pdev->dev;

 	spin_lock_init(&spdif->lock);

 	spdif->pclk = devm_clk_get(&pdev->dev, "spdif");
 	if (IS_ERR(spdif->pclk)) {
 		dev_err(&pdev->dev, "failed to get peri-clock\n");
 		ret = -ENOENT;
 		goto err0;
 	}
 	ret = clk_prepare_enable(spdif->pclk);
 	if (ret)
 		goto err0;

 	spdif->sclk = devm_clk_get(&pdev->dev, "sclk_spdif");
 	if (IS_ERR(spdif->sclk)) {
 		dev_err(&pdev->dev, "failed to get internal source clock\n");
 		ret = -ENOENT;
 		goto err1;
 	}
 	ret = clk_prepare_enable(spdif->sclk);
 	if (ret)
 		goto err1;

 	/* Request S/PDIF Register's memory region */
 	if (!request_mem_region(mem_res->start,
 				resource_size(mem_res), "samsung-spdif")) {
 		dev_err(&pdev->dev, "Unable to request register region\n");
 		ret = -EBUSY;
 		goto err2;
 	}

 	spdif->regs = ioremap(mem_res->start, 0x100);
 	if (spdif->regs == NULL) {
 		dev_err(&pdev->dev, "Cannot ioremap registers\n");
 		ret = -ENXIO;
 		goto err3;
 	}

 	spdif_stereo_out.addr_width = 2;
 	spdif_stereo_out.addr = mem_res->start + DATA_OUTBUF;
 	filter = NULL;
 	if (spdif_pdata) {
 		spdif_stereo_out.filter_data = spdif_pdata->dma_playback;
 		filter = spdif_pdata->dma_filter;
 	}
 	spdif->dma_playback = &spdif_stereo_out;

 	ret = samsung_asoc_dma_platform_register(&pdev->dev, filter,
 						 NULL, NULL, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register DMA: %d\n", ret);
 		goto err4;
 	}

 	dev_set_drvdata(&pdev->dev, spdif);

 	ret = devm_snd_soc_register_component(&pdev->dev,
 			&samsung_spdif_component, &samsung_spdif_dai, 1);
 	if (ret != 0) {
 		dev_err(&pdev->dev, "fail to register dai\n");
 		goto err4;
 	}

 	return 0;
 err4:
 	iounmap(spdif->regs);
 err3:
 	release_mem_region(mem_res->start, resource_size(mem_res));
 err2:
 	clk_disable_unprepare(spdif->sclk);
 err1:
 	clk_disable_unprepare(spdif->pclk);
 err0:
 	return ret;
 }

 static int spdif_remove(struct platform_device *pdev)
 {
 	struct samsung_spdif_info *spdif = &spdif_info;
 	struct resource *mem_res;

 	iounmap(spdif->regs);

 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (mem_res)
 		release_mem_region(mem_res->start, resource_size(mem_res));

 	clk_disable_unprepare(spdif->sclk);
 	clk_disable_unprepare(spdif->pclk);

 	return 0;
 }

 static struct platform_driver samsung_spdif_driver = {
 	.probe	= spdif_probe,
 	.remove	= spdif_remove,
 	.driver	= {
 		.name	= "samsung-spdif",
 	},
 };

 module_platform_driver(samsung_spdif_driver);

 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
 MODULE_DESCRIPTION("Samsung S/PDIF Controller Driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:samsung-spdif");
	// SPDX-License-Identifier: GPL-2.0
	//
	// ALSA SoC Audio Layer - Samsung S/PDIF Controller driver
	//
	// Copyright (c) 2010 Samsung Electronics Co. Ltd
	// http://www.samsung.com/

	#include <linux/clk.h>
	#include <linux/io.h>
	#include <linux/module.h>

	#include <sound/soc.h>
	#include <sound/pcm_params.h>

	#include <linux/platform_data/asoc-s3c.h>

	#include "dma.h"
	#include "spdif.h"

	/* Registers */
	#define CLKCON 0x00
	#define CON 0x04
	#define BSTAS 0x08
	#define CSTAS 0x0C
	#define DATA_OUTBUF 0x10
	#define DCNT 0x14
	#define BSTAS_S 0x18
	#define DCNT_S 0x1C

	#define CLKCTL_MASK 0x7
	#define CLKCTL_MCLK_EXT (0x1 << 2)
	#define CLKCTL_PWR_ON (0x1 << 0)

	#define CON_MASK 0x3ffffff
	#define CON_FIFO_TH_SHIFT 19
	#define CON_FIFO_TH_MASK (0x7 << 19)
	#define CON_USERDATA_23RDBIT (0x1 << 12)

	#define CON_SW_RESET (0x1 << 5)

	#define CON_MCLKDIV_MASK (0x3 << 3)
	#define CON_MCLKDIV_256FS (0x0 << 3)
	#define CON_MCLKDIV_384FS (0x1 << 3)
	#define CON_MCLKDIV_512FS (0x2 << 3)

	#define CON_PCM_MASK (0x3 << 1)
	#define CON_PCM_16BIT (0x0 << 1)
	#define CON_PCM_20BIT (0x1 << 1)
	#define CON_PCM_24BIT (0x2 << 1)

	#define CON_PCM_DATA (0x1 << 0)

	#define CSTAS_MASK 0x3fffffff
	#define CSTAS_SAMP_FREQ_MASK (0xF << 24)
	#define CSTAS_SAMP_FREQ_44 (0x0 << 24)
	#define CSTAS_SAMP_FREQ_48 (0x2 << 24)
	#define CSTAS_SAMP_FREQ_32 (0x3 << 24)
	#define CSTAS_SAMP_FREQ_96 (0xA << 24)

	#define CSTAS_CATEGORY_MASK (0xFF << 8)
	#define CSTAS_CATEGORY_CODE_CDP (0x01 << 8)

	#define CSTAS_NO_COPYRIGHT (0x1 << 2)

	/**
	* struct samsung_spdif_info - Samsung S/PDIF Controller information
	* @lock: Spin lock for S/PDIF.
	* @dev: The parent device passed to use from the probe.
	* @regs: The pointer to the device register block.
	* @clk_rate: Current clock rate for calcurate ratio.
	* @pclk: The peri-clock pointer for spdif master operation.
	* @sclk: The source clock pointer for making sync signals.
	* @saved_clkcon: Backup clkcon reg. in suspend.
	* @saved_con: Backup con reg. in suspend.
	* @saved_cstas: Backup cstas reg. in suspend.
	* @dma_playback: DMA information for playback channel.
	*/
	struct samsung_spdif_info {
	spinlock_t lock;
	struct device *dev;
	void __iomem *regs;
	unsigned long clk_rate;
	struct clk *pclk;
	struct clk *sclk;
	u32 saved_clkcon;
	u32 saved_con;
	u32 saved_cstas;
	struct snd_dmaengine_dai_dma_data *dma_playback;
	};

	static struct snd_dmaengine_dai_dma_data spdif_stereo_out;
	static struct samsung_spdif_info spdif_info;

	static inline struct samsung_spdif_info
	component_to_info(struct snd_soc_component component)
	{
	return snd_soc_component_get_drvdata(component);
	}

	static inline struct samsung_spdif_info to_info(struct snd_soc_dai cpu_dai)
	{
	return snd_soc_dai_get_drvdata(cpu_dai);
	}

	static void spdif_snd_txctrl(struct samsung_spdif_info *spdif, int on)
	{
	void __iomem *regs = spdif->regs;
	u32 clkcon;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;
	if (on)
	writel(clkcon \| CLKCTL_PWR_ON, regs + CLKCON);
	else
	writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
	}

	static int spdif_set_sysclk(struct snd_soc_dai *cpu_dai,
	int clk_id, unsigned int freq, int dir)
	{
	struct samsung_spdif_info *spdif = to_info(cpu_dai);
	u32 clkcon;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	clkcon = readl(spdif->regs + CLKCON);

	if (clk_id == SND_SOC_SPDIF_INT_MCLK)
	clkcon &= ~CLKCTL_MCLK_EXT;
	else
	clkcon \|= CLKCTL_MCLK_EXT;

	writel(clkcon, spdif->regs + CLKCON);

	spdif->clk_rate = freq;

	return 0;
	}

	static int spdif_trigger(struct snd_pcm_substream *substream, int cmd,
	struct snd_soc_dai *dai)
	{
	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
	unsigned long flags;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	spin_lock_irqsave(&spdif->lock, flags);
	spdif_snd_txctrl(spdif, 1);
	spin_unlock_irqrestore(&spdif->lock, flags);
	break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	spin_lock_irqsave(&spdif->lock, flags);
	spdif_snd_txctrl(spdif, 0);
	spin_unlock_irqrestore(&spdif->lock, flags);
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	static int spdif_sysclk_ratios[] = {
	512, 384, 256,
	};

	static int spdif_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params,
	struct snd_soc_dai *socdai)
	{
	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
	void __iomem *regs = spdif->regs;
	struct snd_dmaengine_dai_dma_data *dma_data;
	u32 con, clkcon, cstas;
	unsigned long flags;
	int i, ratio;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
	dma_data = spdif->dma_playback;
	else {
	dev_err(spdif->dev, "Capture is not supported\n");
	return -EINVAL;
	}

	snd_soc_dai_set_dma_data(asoc_rtd_to_cpu(rtd, 0), substream, dma_data);

	spin_lock_irqsave(&spdif->lock, flags);

	con = readl(regs + CON) & CON_MASK;
	cstas = readl(regs + CSTAS) & CSTAS_MASK;
	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;

	con &= ~CON_FIFO_TH_MASK;
	con \|= (0x7 << CON_FIFO_TH_SHIFT);
	con \|= CON_USERDATA_23RDBIT;
	con \|= CON_PCM_DATA;

	con &= ~CON_PCM_MASK;
	switch (params_width(params)) {
	case 16:
	con \|= CON_PCM_16BIT;
	break;
	default:
	dev_err(spdif->dev, "Unsupported data size.\n");
	goto err;
	}

	ratio = spdif->clk_rate / params_rate(params);
	for (i = 0; i < ARRAY_SIZE(spdif_sysclk_ratios); i++)
	if (ratio == spdif_sysclk_ratios[i])
	break;
	if (i == ARRAY_SIZE(spdif_sysclk_ratios)) {
	dev_err(spdif->dev, "Invalid clock ratio %ld/%d\n",
	spdif->clk_rate, params_rate(params));
	goto err;
	}

	con &= ~CON_MCLKDIV_MASK;
	switch (ratio) {
	case 256:
	con \|= CON_MCLKDIV_256FS;
	break;
	case 384:
	con \|= CON_MCLKDIV_384FS;
	break;
	case 512:
	con \|= CON_MCLKDIV_512FS;
	break;
	}

	cstas &= ~CSTAS_SAMP_FREQ_MASK;
	switch (params_rate(params)) {
	case 44100:
	cstas \|= CSTAS_SAMP_FREQ_44;
	break;
	case 48000:
	cstas \|= CSTAS_SAMP_FREQ_48;
	break;
	case 32000:
	cstas \|= CSTAS_SAMP_FREQ_32;
	break;
	case 96000:
	cstas \|= CSTAS_SAMP_FREQ_96;
	break;
	default:
	dev_err(spdif->dev, "Invalid sampling rate %d\n",
	params_rate(params));
	goto err;
	}

	cstas &= ~CSTAS_CATEGORY_MASK;
	cstas \|= CSTAS_CATEGORY_CODE_CDP;
	cstas \|= CSTAS_NO_COPYRIGHT;

	writel(con, regs + CON);
	writel(cstas, regs + CSTAS);
	writel(clkcon, regs + CLKCON);

	spin_unlock_irqrestore(&spdif->lock, flags);

	return 0;
	err:
	spin_unlock_irqrestore(&spdif->lock, flags);
	return -EINVAL;
	}

	static void spdif_shutdown(struct snd_pcm_substream *substream,
	struct snd_soc_dai *dai)
	{
	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
	struct samsung_spdif_info *spdif = to_info(asoc_rtd_to_cpu(rtd, 0));
	void __iomem *regs = spdif->regs;
	u32 con, clkcon;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	con = readl(regs + CON) & CON_MASK;
	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;

	writel(con \| CON_SW_RESET, regs + CON);
	cpu_relax();

	writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
	}

	#ifdef CONFIG_PM
	static int spdif_suspend(struct snd_soc_component *component)
	{
	struct samsung_spdif_info *spdif = component_to_info(component);
	u32 con = spdif->saved_con;

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	spdif->saved_clkcon = readl(spdif->regs + CLKCON) & CLKCTL_MASK;
	spdif->saved_con = readl(spdif->regs + CON) & CON_MASK;
	spdif->saved_cstas = readl(spdif->regs + CSTAS) & CSTAS_MASK;

	writel(con \| CON_SW_RESET, spdif->regs + CON);
	cpu_relax();

	return 0;
	}

	static int spdif_resume(struct snd_soc_component *component)
	{
	struct samsung_spdif_info *spdif = component_to_info(component);

	dev_dbg(spdif->dev, "Entered %s\n", __func__);

	writel(spdif->saved_clkcon, spdif->regs + CLKCON);
	writel(spdif->saved_con, spdif->regs + CON);
	writel(spdif->saved_cstas, spdif->regs + CSTAS);

	return 0;
	}
	#else
	#define spdif_suspend NULL
	#define spdif_resume NULL
	#endif

	static const struct snd_soc_dai_ops spdif_dai_ops = {
	.set_sysclk = spdif_set_sysclk,
	.trigger = spdif_trigger,
	.hw_params = spdif_hw_params,
	.shutdown = spdif_shutdown,
	};

	static struct snd_soc_dai_driver samsung_spdif_dai = {
	.name = "samsung-spdif",
	.playback = {
	.stream_name = "S/PDIF Playback",
	.channels_min = 2,
	.channels_max = 2,
	.rates = (SNDRV_PCM_RATE_32000 \|
	SNDRV_PCM_RATE_44100 \|
	SNDRV_PCM_RATE_48000 \|
	SNDRV_PCM_RATE_96000),
	.formats = SNDRV_PCM_FMTBIT_S16_LE, },
	.ops = &spdif_dai_ops,
	};

	static const struct snd_soc_component_driver samsung_spdif_component = {
	.name = "samsung-spdif",
	.suspend = spdif_suspend,
	.resume = spdif_resume,
	};

	static int spdif_probe(struct platform_device *pdev)
	{
	struct s3c_audio_pdata *spdif_pdata;
	struct resource *mem_res;
	struct samsung_spdif_info *spdif;
	dma_filter_fn filter;
	int ret;

	spdif_pdata = pdev->dev.platform_data;

	dev_dbg(&pdev->dev, "Entered %s\n", __func__);

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem_res) {
	dev_err(&pdev->dev, "Unable to get register resource.\n");
	return -ENXIO;
	}

	if (spdif_pdata && spdif_pdata->cfg_gpio
	&& spdif_pdata->cfg_gpio(pdev)) {
	dev_err(&pdev->dev, "Unable to configure GPIO pins\n");
	return -EINVAL;
	}

	spdif = &spdif_info;
	spdif->dev = &pdev->dev;

	spin_lock_init(&spdif->lock);

	spdif->pclk = devm_clk_get(&pdev->dev, "spdif");
	if (IS_ERR(spdif->pclk)) {
	dev_err(&pdev->dev, "failed to get peri-clock\n");
	ret = -ENOENT;
	goto err0;
	}
	ret = clk_prepare_enable(spdif->pclk);
	if (ret)
	goto err0;

	spdif->sclk = devm_clk_get(&pdev->dev, "sclk_spdif");
	if (IS_ERR(spdif->sclk)) {
	dev_err(&pdev->dev, "failed to get internal source clock\n");
	ret = -ENOENT;
	goto err1;
	}
	ret = clk_prepare_enable(spdif->sclk);
	if (ret)
	goto err1;

	/* Request S/PDIF Register's memory region */
	if (!request_mem_region(mem_res->start,
	resource_size(mem_res), "samsung-spdif")) {
	dev_err(&pdev->dev, "Unable to request register region\n");
	ret = -EBUSY;
	goto err2;
	}

	spdif->regs = ioremap(mem_res->start, 0x100);
	if (spdif->regs == NULL) {
	dev_err(&pdev->dev, "Cannot ioremap registers\n");
	ret = -ENXIO;
	goto err3;
	}

	spdif_stereo_out.addr_width = 2;
	spdif_stereo_out.addr = mem_res->start + DATA_OUTBUF;
	filter = NULL;
	if (spdif_pdata) {
	spdif_stereo_out.filter_data = spdif_pdata->dma_playback;
	filter = spdif_pdata->dma_filter;
	}
	spdif->dma_playback = &spdif_stereo_out;

	ret = samsung_asoc_dma_platform_register(&pdev->dev, filter,
	NULL, NULL, NULL);
	if (ret) {
	dev_err(&pdev->dev, "failed to register DMA: %d\n", ret);
	goto err4;
	}

	dev_set_drvdata(&pdev->dev, spdif);

	ret = devm_snd_soc_register_component(&pdev->dev,
	&samsung_spdif_component, &samsung_spdif_dai, 1);
	if (ret != 0) {
	dev_err(&pdev->dev, "fail to register dai\n");
	goto err4;
	}

	return 0;
	err4:
	iounmap(spdif->regs);
	err3:
	release_mem_region(mem_res->start, resource_size(mem_res));
	err2:
	clk_disable_unprepare(spdif->sclk);
	err1:
	clk_disable_unprepare(spdif->pclk);
	err0:
	return ret;
	}

	static int spdif_remove(struct platform_device *pdev)
	{
	struct samsung_spdif_info *spdif = &spdif_info;
	struct resource *mem_res;

	iounmap(spdif->regs);

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (mem_res)
	release_mem_region(mem_res->start, resource_size(mem_res));

	clk_disable_unprepare(spdif->sclk);
	clk_disable_unprepare(spdif->pclk);

	return 0;
	}

	static struct platform_driver samsung_spdif_driver = {
	.probe = spdif_probe,
	.remove = spdif_remove,
	.driver = {
	.name = "samsung-spdif",
	},
	};

	module_platform_driver(samsung_spdif_driver);

	MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
	MODULE_DESCRIPTION("Samsung S/PDIF Controller Driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:samsung-spdif");