sound/soc/img/img-spdif-out.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * IMG SPDIF output controller driver
  *
  * Copyright (C) 2015 Imagination Technologies Ltd.
  *
  * Author: Damien Horsley <Damien.Horsley@imgtec.com>
  */

 #include <linux/clk.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>

 #include <sound/core.h>
 #include <sound/dmaengine_pcm.h>
 #include <sound/initval.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>

 #define IMG_SPDIF_OUT_TX_FIFO		0x0

 #define IMG_SPDIF_OUT_CTL		0x4
 #define IMG_SPDIF_OUT_CTL_FS_MASK	BIT(4)
 #define IMG_SPDIF_OUT_CTL_CLK_MASK	BIT(2)
 #define IMG_SPDIF_OUT_CTL_SRT_MASK	BIT(0)

 #define IMG_SPDIF_OUT_CSL		0x14

 #define IMG_SPDIF_OUT_CSH_UV		0x18
 #define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT	0
 #define IMG_SPDIF_OUT_CSH_UV_CSH_MASK	0xff

 struct img_spdif_out {
 	spinlock_t lock;
 	void __iomem *base;
 	struct clk *clk_sys;
 	struct clk *clk_ref;
 	struct snd_dmaengine_dai_dma_data dma_data;
 	struct device *dev;
 	struct reset_control *rst;
 	u32 suspend_ctl;
 	u32 suspend_csl;
 	u32 suspend_csh;
 };

 static int img_spdif_out_runtime_suspend(struct device *dev)
 {
 	struct img_spdif_out *spdif = dev_get_drvdata(dev);

 	clk_disable_unprepare(spdif->clk_ref);
 	clk_disable_unprepare(spdif->clk_sys);

 	return 0;
 }

 static int img_spdif_out_runtime_resume(struct device *dev)
 {
 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
 	int ret;

 	ret = clk_prepare_enable(spdif->clk_sys);
 	if (ret) {
 		dev_err(dev, "clk_enable failed: %d\n", ret);
 		return ret;
 	}

 	ret = clk_prepare_enable(spdif->clk_ref);
 	if (ret) {
 		dev_err(dev, "clk_enable failed: %d\n", ret);
 		clk_disable_unprepare(spdif->clk_sys);
 		return ret;
 	}

 	return 0;
 }

 static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
 				u32 reg)
 {
 	writel(val, spdif->base + reg);
 }

 static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
 {
 	return readl(spdif->base + reg);
 }

 static void img_spdif_out_reset(struct img_spdif_out *spdif)
 {
 	u32 ctl, status_low, status_high;

 	ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
 			~IMG_SPDIF_OUT_CTL_SRT_MASK;
 	status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
 	status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);

 	reset_control_assert(spdif->rst);
 	reset_control_deassert(spdif->rst);

 	img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
 	img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
 	img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
 }

 static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
 					struct snd_ctl_elem_info *uinfo)
 {
 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
 	uinfo->count = 1;

 	return 0;
 }

 static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
 				       struct snd_ctl_elem_value *ucontrol)
 {
 	ucontrol->value.iec958.status[0] = 0xff;
 	ucontrol->value.iec958.status[1] = 0xff;
 	ucontrol->value.iec958.status[2] = 0xff;
 	ucontrol->value.iec958.status[3] = 0xff;
 	ucontrol->value.iec958.status[4] = 0xff;

 	return 0;
 }

 static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
 				  struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
 	u32 reg;
 	unsigned long flags;

 	spin_lock_irqsave(&spdif->lock, flags);

 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
 	ucontrol->value.iec958.status[0] = reg & 0xff;
 	ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
 	ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
 	ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;

 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
 	ucontrol->value.iec958.status[4] =
 		(reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
 		IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;

 	spin_unlock_irqrestore(&spdif->lock, flags);

 	return 0;
 }

 static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
 				  struct snd_ctl_elem_value *ucontrol)
 {
 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
 	u32 reg;
 	unsigned long flags;

 	reg = ((u32)ucontrol->value.iec958.status[3] << 24);
 	reg |= ((u32)ucontrol->value.iec958.status[2] << 16);
 	reg |= ((u32)ucontrol->value.iec958.status[1] << 8);
 	reg |= (u32)ucontrol->value.iec958.status[0];

 	spin_lock_irqsave(&spdif->lock, flags);

 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);

 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
 	reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
 	reg |= (u32)ucontrol->value.iec958.status[4] <<
 			IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);

 	spin_unlock_irqrestore(&spdif->lock, flags);

 	return 0;
 }

 static struct snd_kcontrol_new img_spdif_out_controls[] = {
 	{
 		.access = SNDRV_CTL_ELEM_ACCESS_READ,
 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
 		.info = img_spdif_out_info,
 		.get = img_spdif_out_get_status_mask
 	},
 	{
 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
 		.info = img_spdif_out_info,
 		.get = img_spdif_out_get_status,
 		.put = img_spdif_out_set_status
 	}
 };

 static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
 			struct snd_soc_dai *dai)
 {
 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
 	u32 reg;
 	unsigned long flags;

 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
 		reg |= IMG_SPDIF_OUT_CTL_SRT_MASK;
 		img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		spin_lock_irqsave(&spdif->lock, flags);
 		img_spdif_out_reset(spdif);
 		spin_unlock_irqrestore(&spdif->lock, flags);
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
 	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
 {
 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
 	unsigned int channels;
 	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
 	u32 reg;
 	snd_pcm_format_t format;

 	rate = params_rate(params);
 	format = params_format(params);
 	channels = params_channels(params);

 	dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
 			rate, channels, format);

 	if (format != SNDRV_PCM_FORMAT_S32_LE)
 		return -EINVAL;

 	if (channels != 2)
 		return -EINVAL;

 	pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
 	if (pre_div_a < 0)
 		return pre_div_a;
 	pre_div_b = clk_round_rate(spdif->clk_ref, rate * 384);
 	if (pre_div_b < 0)
 		return pre_div_b;

 	diff_a = abs((pre_div_a / 256) - rate);
 	diff_b = abs((pre_div_b / 384) - rate);

 	/* If diffs are equal, use lower clock rate */
 	if (diff_a > diff_b)
 		clk_set_rate(spdif->clk_ref, pre_div_b);
 	else
 		clk_set_rate(spdif->clk_ref, pre_div_a);

 	/*
 	 * Another driver (eg machine driver) may have rejected the above
 	 * change. Get the current rate and set the register bit according to
 	 * the new min diff
 	 */
 	clk_rate = clk_get_rate(spdif->clk_ref);

 	diff_a = abs((clk_rate / 256) - rate);
 	diff_b = abs((clk_rate / 384) - rate);

 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
 	if (diff_a <= diff_b)
 		reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
 	else
 		reg |= IMG_SPDIF_OUT_CTL_CLK_MASK;
 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);

 	return 0;
 }

 static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
 {
 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);

 	snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);

 	snd_soc_add_dai_controls(dai, img_spdif_out_controls,
 			ARRAY_SIZE(img_spdif_out_controls));

 	return 0;
 }

 static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
 	.probe		= img_spdif_out_dai_probe,
 	.trigger	= img_spdif_out_trigger,
 	.hw_params	= img_spdif_out_hw_params
 };

 static struct snd_soc_dai_driver img_spdif_out_dai = {
 	.playback = {
 		.channels_min = 2,
 		.channels_max = 2,
 		.rates = SNDRV_PCM_RATE_8000_192000,
 		.formats = SNDRV_PCM_FMTBIT_S32_LE
 	},
 	.ops = &img_spdif_out_dai_ops
 };

 static const struct snd_soc_component_driver img_spdif_out_component = {
 	.name = "img-spdif-out",
 	.legacy_dai_naming = 1,
 };

 static int img_spdif_out_probe(struct platform_device *pdev)
 {
 	struct img_spdif_out *spdif;
 	struct resource *res;
 	void __iomem *base;
 	int ret;
 	struct device *dev = &pdev->dev;

 	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
 	if (!spdif)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, spdif);

 	spdif->dev = &pdev->dev;

 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);

 	spdif->base = base;

 	spdif->rst = devm_reset_control_get_exclusive(&pdev->dev, "rst");
 	if (IS_ERR(spdif->rst))
 		return dev_err_probe(&pdev->dev, PTR_ERR(spdif->rst),
 				     "No top level reset found\n");

 	spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
 	if (IS_ERR(spdif->clk_sys))
 		return dev_err_probe(dev, PTR_ERR(spdif->clk_sys),
 				     "Failed to acquire clock 'sys'\n");

 	spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
 	if (IS_ERR(spdif->clk_ref))
 		return dev_err_probe(dev, PTR_ERR(spdif->clk_ref),
 				     "Failed to acquire clock 'ref'\n");

 	pm_runtime_enable(&pdev->dev);
 	if (!pm_runtime_enabled(&pdev->dev)) {
 		ret = img_spdif_out_runtime_resume(&pdev->dev);
 		if (ret)
 			goto err_pm_disable;
 	}
 	ret = pm_runtime_resume_and_get(&pdev->dev);
 	if (ret < 0)
 		goto err_suspend;

 	img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
 			     IMG_SPDIF_OUT_CTL);

 	img_spdif_out_reset(spdif);
 	pm_runtime_put(&pdev->dev);

 	spin_lock_init(&spdif->lock);

 	spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
 	spdif->dma_data.addr_width = 4;
 	spdif->dma_data.maxburst = 4;

 	ret = devm_snd_soc_register_component(&pdev->dev,
 			&img_spdif_out_component,
 			&img_spdif_out_dai, 1);
 	if (ret)
 		goto err_suspend;

 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
 	if (ret)
 		goto err_suspend;

 	dev_dbg(&pdev->dev, "Probe successful\n");

 	return 0;

 err_suspend:
 	if (!pm_runtime_status_suspended(&pdev->dev))
 		img_spdif_out_runtime_suspend(&pdev->dev);
 err_pm_disable:
 	pm_runtime_disable(&pdev->dev);

 	return ret;
 }

 static void img_spdif_out_dev_remove(struct platform_device *pdev)
 {
 	pm_runtime_disable(&pdev->dev);
 	if (!pm_runtime_status_suspended(&pdev->dev))
 		img_spdif_out_runtime_suspend(&pdev->dev);
 }

 static int img_spdif_out_suspend(struct device *dev)
 {
 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
 	int ret;

 	if (pm_runtime_status_suspended(dev)) {
 		ret = img_spdif_out_runtime_resume(dev);
 		if (ret)
 			return ret;
 	}

 	spdif->suspend_ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
 	spdif->suspend_csl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
 	spdif->suspend_csh = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);

 	img_spdif_out_runtime_suspend(dev);

 	return 0;
 }

 static int img_spdif_out_resume(struct device *dev)
 {
 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
 	int ret;

 	ret = img_spdif_out_runtime_resume(dev);
 	if (ret)
 		return ret;

 	img_spdif_out_writel(spdif, spdif->suspend_ctl, IMG_SPDIF_OUT_CTL);
 	img_spdif_out_writel(spdif, spdif->suspend_csl, IMG_SPDIF_OUT_CSL);
 	img_spdif_out_writel(spdif, spdif->suspend_csh, IMG_SPDIF_OUT_CSH_UV);

 	if (pm_runtime_status_suspended(dev))
 		img_spdif_out_runtime_suspend(dev);

 	return 0;
 }

 static const struct of_device_id img_spdif_out_of_match[] = {
 	{ .compatible = "img,spdif-out" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);

 static const struct dev_pm_ops img_spdif_out_pm_ops = {
 	RUNTIME_PM_OPS(img_spdif_out_runtime_suspend, img_spdif_out_runtime_resume, NULL)
 	SYSTEM_SLEEP_PM_OPS(img_spdif_out_suspend, img_spdif_out_resume)
 };

 static struct platform_driver img_spdif_out_driver = {
 	.driver = {
 		.name = "img-spdif-out",
 		.of_match_table = img_spdif_out_of_match,
 		.pm = pm_ptr(&img_spdif_out_pm_ops)
 	},
 	.probe = img_spdif_out_probe,
 	.remove = img_spdif_out_dev_remove
 };
 module_platform_driver(img_spdif_out_driver);

 MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
 MODULE_DESCRIPTION("IMG SPDIF Output driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* IMG SPDIF output controller driver
	*
	* Copyright (C) 2015 Imagination Technologies Ltd.
	*
	* Author: Damien Horsley <Damien.Horsley@imgtec.com>
	*/

	#include <linux/clk.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/reset.h>

	#include <sound/core.h>
	#include <sound/dmaengine_pcm.h>
	#include <sound/initval.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/soc.h>

	#define IMG_SPDIF_OUT_TX_FIFO 0x0

	#define IMG_SPDIF_OUT_CTL 0x4
	#define IMG_SPDIF_OUT_CTL_FS_MASK BIT(4)
	#define IMG_SPDIF_OUT_CTL_CLK_MASK BIT(2)
	#define IMG_SPDIF_OUT_CTL_SRT_MASK BIT(0)

	#define IMG_SPDIF_OUT_CSL 0x14

	#define IMG_SPDIF_OUT_CSH_UV 0x18
	#define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT 0
	#define IMG_SPDIF_OUT_CSH_UV_CSH_MASK 0xff

	struct img_spdif_out {
	spinlock_t lock;
	void __iomem *base;
	struct clk *clk_sys;
	struct clk *clk_ref;
	struct snd_dmaengine_dai_dma_data dma_data;
	struct device *dev;
	struct reset_control *rst;
	u32 suspend_ctl;
	u32 suspend_csl;
	u32 suspend_csh;
	};

	static int img_spdif_out_runtime_suspend(struct device *dev)
	{
	struct img_spdif_out *spdif = dev_get_drvdata(dev);

	clk_disable_unprepare(spdif->clk_ref);
	clk_disable_unprepare(spdif->clk_sys);

	return 0;
	}

	static int img_spdif_out_runtime_resume(struct device *dev)
	{
	struct img_spdif_out *spdif = dev_get_drvdata(dev);
	int ret;

	ret = clk_prepare_enable(spdif->clk_sys);
	if (ret) {
	dev_err(dev, "clk_enable failed: %d\n", ret);
	return ret;
	}

	ret = clk_prepare_enable(spdif->clk_ref);
	if (ret) {
	dev_err(dev, "clk_enable failed: %d\n", ret);
	clk_disable_unprepare(spdif->clk_sys);
	return ret;
	}

	return 0;
	}

	static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
	u32 reg)
	{
	writel(val, spdif->base + reg);
	}

	static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
	{
	return readl(spdif->base + reg);
	}

	static void img_spdif_out_reset(struct img_spdif_out *spdif)
	{
	u32 ctl, status_low, status_high;

	ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
	~IMG_SPDIF_OUT_CTL_SRT_MASK;
	status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
	status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);

	reset_control_assert(spdif->rst);
	reset_control_deassert(spdif->rst);

	img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
	img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
	img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
	}

	static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_info *uinfo)
	{
	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
	uinfo->count = 1;

	return 0;
	}

	static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	ucontrol->value.iec958.status[0] = 0xff;
	ucontrol->value.iec958.status[1] = 0xff;
	ucontrol->value.iec958.status[2] = 0xff;
	ucontrol->value.iec958.status[3] = 0xff;
	ucontrol->value.iec958.status[4] = 0xff;

	return 0;
	}

	static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
	u32 reg;
	unsigned long flags;

	spin_lock_irqsave(&spdif->lock, flags);

	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
	ucontrol->value.iec958.status[0] = reg & 0xff;
	ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
	ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
	ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;

	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
	ucontrol->value.iec958.status[4] =
	(reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
	IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;

	spin_unlock_irqrestore(&spdif->lock, flags);

	return 0;
	}

	static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
	struct snd_ctl_elem_value *ucontrol)
	{
	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
	u32 reg;
	unsigned long flags;

	reg = ((u32)ucontrol->value.iec958.status[3] << 24);
	reg \|= ((u32)ucontrol->value.iec958.status[2] << 16);
	reg \|= ((u32)ucontrol->value.iec958.status[1] << 8);
	reg \|= (u32)ucontrol->value.iec958.status[0];

	spin_lock_irqsave(&spdif->lock, flags);

	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);

	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
	reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
	reg \|= (u32)ucontrol->value.iec958.status[4] <<
	IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);

	spin_unlock_irqrestore(&spdif->lock, flags);

	return 0;
	}

	static struct snd_kcontrol_new img_spdif_out_controls[] = {
	{
	.access = SNDRV_CTL_ELEM_ACCESS_READ,
	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
	.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
	.info = img_spdif_out_info,
	.get = img_spdif_out_get_status_mask
	},
	{
	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
	.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
	.info = img_spdif_out_info,
	.get = img_spdif_out_get_status,
	.put = img_spdif_out_set_status
	}
	};

	static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
	struct snd_soc_dai *dai)
	{
	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
	u32 reg;
	unsigned long flags;

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
	reg \|= IMG_SPDIF_OUT_CTL_SRT_MASK;
	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
	break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	spin_lock_irqsave(&spdif->lock, flags);
	img_spdif_out_reset(spdif);
	spin_unlock_irqrestore(&spdif->lock, flags);
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params params, struct snd_soc_dai dai)
	{
	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
	unsigned int channels;
	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
	u32 reg;
	snd_pcm_format_t format;

	rate = params_rate(params);
	format = params_format(params);
	channels = params_channels(params);

	dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
	rate, channels, format);

	if (format != SNDRV_PCM_FORMAT_S32_LE)
	return -EINVAL;

	if (channels != 2)
	return -EINVAL;

	pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
	if (pre_div_a < 0)
	return pre_div_a;
	pre_div_b = clk_round_rate(spdif->clk_ref, rate * 384);
	if (pre_div_b < 0)
	return pre_div_b;

	diff_a = abs((pre_div_a / 256) - rate);
	diff_b = abs((pre_div_b / 384) - rate);

	/* If diffs are equal, use lower clock rate */
	if (diff_a > diff_b)
	clk_set_rate(spdif->clk_ref, pre_div_b);
	else
	clk_set_rate(spdif->clk_ref, pre_div_a);

	/*
	* Another driver (eg machine driver) may have rejected the above
	* change. Get the current rate and set the register bit according to
	* the new min diff
	*/
	clk_rate = clk_get_rate(spdif->clk_ref);

	diff_a = abs((clk_rate / 256) - rate);
	diff_b = abs((clk_rate / 384) - rate);

	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
	if (diff_a <= diff_b)
	reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
	else
	reg \|= IMG_SPDIF_OUT_CTL_CLK_MASK;
	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);

	return 0;
	}

	static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
	{
	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);

	snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);

	snd_soc_add_dai_controls(dai, img_spdif_out_controls,
	ARRAY_SIZE(img_spdif_out_controls));

	return 0;
	}

	static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
	.probe = img_spdif_out_dai_probe,
	.trigger = img_spdif_out_trigger,
	.hw_params = img_spdif_out_hw_params
	};

	static struct snd_soc_dai_driver img_spdif_out_dai = {
	.playback = {
	.channels_min = 2,
	.channels_max = 2,
	.rates = SNDRV_PCM_RATE_8000_192000,
	.formats = SNDRV_PCM_FMTBIT_S32_LE
	},
	.ops = &img_spdif_out_dai_ops
	};

	static const struct snd_soc_component_driver img_spdif_out_component = {
	.name = "img-spdif-out",
	.legacy_dai_naming = 1,
	};

	static int img_spdif_out_probe(struct platform_device *pdev)
	{
	struct img_spdif_out *spdif;
	struct resource *res;
	void __iomem *base;
	int ret;
	struct device *dev = &pdev->dev;

	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
	if (!spdif)
	return -ENOMEM;

	platform_set_drvdata(pdev, spdif);

	spdif->dev = &pdev->dev;

	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
	if (IS_ERR(base))
	return PTR_ERR(base);

	spdif->base = base;

	spdif->rst = devm_reset_control_get_exclusive(&pdev->dev, "rst");
	if (IS_ERR(spdif->rst))
	return dev_err_probe(&pdev->dev, PTR_ERR(spdif->rst),
	"No top level reset found\n");

	spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
	if (IS_ERR(spdif->clk_sys))
	return dev_err_probe(dev, PTR_ERR(spdif->clk_sys),
	"Failed to acquire clock 'sys'\n");

	spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
	if (IS_ERR(spdif->clk_ref))
	return dev_err_probe(dev, PTR_ERR(spdif->clk_ref),
	"Failed to acquire clock 'ref'\n");

	pm_runtime_enable(&pdev->dev);
	if (!pm_runtime_enabled(&pdev->dev)) {
	ret = img_spdif_out_runtime_resume(&pdev->dev);
	if (ret)
	goto err_pm_disable;
	}
	ret = pm_runtime_resume_and_get(&pdev->dev);
	if (ret < 0)
	goto err_suspend;

	img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
	IMG_SPDIF_OUT_CTL);

	img_spdif_out_reset(spdif);
	pm_runtime_put(&pdev->dev);

	spin_lock_init(&spdif->lock);

	spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
	spdif->dma_data.addr_width = 4;
	spdif->dma_data.maxburst = 4;

	ret = devm_snd_soc_register_component(&pdev->dev,
	&img_spdif_out_component,
	&img_spdif_out_dai, 1);
	if (ret)
	goto err_suspend;

	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
	if (ret)
	goto err_suspend;

	dev_dbg(&pdev->dev, "Probe successful\n");

	return 0;

	err_suspend:
	if (!pm_runtime_status_suspended(&pdev->dev))
	img_spdif_out_runtime_suspend(&pdev->dev);
	err_pm_disable:
	pm_runtime_disable(&pdev->dev);

	return ret;
	}

	static void img_spdif_out_dev_remove(struct platform_device *pdev)
	{
	pm_runtime_disable(&pdev->dev);
	if (!pm_runtime_status_suspended(&pdev->dev))
	img_spdif_out_runtime_suspend(&pdev->dev);
	}

	static int img_spdif_out_suspend(struct device *dev)
	{
	struct img_spdif_out *spdif = dev_get_drvdata(dev);
	int ret;

	if (pm_runtime_status_suspended(dev)) {
	ret = img_spdif_out_runtime_resume(dev);
	if (ret)
	return ret;
	}

	spdif->suspend_ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
	spdif->suspend_csl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
	spdif->suspend_csh = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);

	img_spdif_out_runtime_suspend(dev);

	return 0;
	}

	static int img_spdif_out_resume(struct device *dev)
	{
	struct img_spdif_out *spdif = dev_get_drvdata(dev);
	int ret;

	ret = img_spdif_out_runtime_resume(dev);
	if (ret)
	return ret;

	img_spdif_out_writel(spdif, spdif->suspend_ctl, IMG_SPDIF_OUT_CTL);
	img_spdif_out_writel(spdif, spdif->suspend_csl, IMG_SPDIF_OUT_CSL);
	img_spdif_out_writel(spdif, spdif->suspend_csh, IMG_SPDIF_OUT_CSH_UV);

	if (pm_runtime_status_suspended(dev))
	img_spdif_out_runtime_suspend(dev);

	return 0;
	}

	static const struct of_device_id img_spdif_out_of_match[] = {
	{ .compatible = "img,spdif-out" },
	{}
	};
	MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);

	static const struct dev_pm_ops img_spdif_out_pm_ops = {
	RUNTIME_PM_OPS(img_spdif_out_runtime_suspend, img_spdif_out_runtime_resume, NULL)
	SYSTEM_SLEEP_PM_OPS(img_spdif_out_suspend, img_spdif_out_resume)
	};

	static struct platform_driver img_spdif_out_driver = {
	.driver = {
	.name = "img-spdif-out",
	.of_match_table = img_spdif_out_of_match,
	.pm = pm_ptr(&img_spdif_out_pm_ops)
	},
	.probe = img_spdif_out_probe,
	.remove = img_spdif_out_dev_remove
	};
	module_platform_driver(img_spdif_out_driver);

	MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
	MODULE_DESCRIPTION("IMG SPDIF Output driver");
	MODULE_LICENSE("GPL v2");