openwrt/target/linux/starfive/patches-6.6/0080-ASoC-starfive-Add-SPDIF-and-PCM-driver.patch

From f03b7c834baef87e4f740e10a8bbcbfc57bd985a Mon Sep 17 00:00:00 2001
From: Xingyu Wu <xingyu.wu@starfivetech.com>
Date: Thu, 15 Jun 2023 11:32:50 +0800
Subject: [PATCH 080/116] ASoC: starfive: Add SPDIF and PCM driver

Add SPDIF and SPDIF-PCM driver for StarFive JH7110.

Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
---
 sound/soc/starfive/Kconfig            |  17 +
 sound/soc/starfive/Makefile           |   5 +
 sound/soc/starfive/jh7110_spdif.c     | 568 ++++++++++++++++++++++++++
 sound/soc/starfive/jh7110_spdif.h     | 196 +++++++++
 sound/soc/starfive/jh7110_spdif_pcm.c | 339 +++++++++++++++
 5 files changed, 1125 insertions(+)
 create mode 100644 sound/soc/starfive/jh7110_spdif.c
 create mode 100644 sound/soc/starfive/jh7110_spdif.h
 create mode 100644 sound/soc/starfive/jh7110_spdif_pcm.c

--- a/sound/soc/starfive/Kconfig
+++ b/sound/soc/starfive/Kconfig
@@ -16,6 +16,23 @@ config SND_SOC_JH7110_PWMDAC
 	 Say Y or M if you want to add support for StarFive JH7110
 	 PWM-DAC driver.
 
+config SND_SOC_JH7110_SPDIF
+	tristate "JH7110 SPDIF module"
+	depends on HAVE_CLK && SND_SOC_STARFIVE
+	select SND_SOC_GENERIC_DMAENGINE_PCM
+	select REGMAP_MMIO
+	help
+	  Say Y or M if you want to add support for SPDIF driver of StarFive
+	  JH7110 SoC.
+
+config SND_SOC_JH7110_SPDIF_PCM
+	bool "PCM PIO extension for JH7110 SPDIF"
+	depends on SND_SOC_JH7110_SPDIF
+	default y if SND_SOC_JH7110_SPDIF
+	help
+	  Say Y or N if you want to add a custom ALSA extension that registers
+	  a PCM and uses PIO to transfer data.
+
 config SND_SOC_JH7110_TDM
 	tristate "JH7110 TDM device driver"
 	depends on HAVE_CLK && SND_SOC_STARFIVE
--- a/sound/soc/starfive/Makefile
+++ b/sound/soc/starfive/Makefile
@@ -1,3 +1,8 @@
 # StarFive Platform Support
 obj-$(CONFIG_SND_SOC_JH7110_PWMDAC) += jh7110_pwmdac.o
+
+obj-$(CONFIG_SND_SOC_JH7110_SPDIF) += spdif.o
+spdif-y := jh7110_spdif.o
+spdif-$(CONFIG_SND_SOC_JH7110_SPDIF_PCM) += jh7110_spdif_pcm.o
+
 obj-$(CONFIG_SND_SOC_JH7110_TDM) += jh7110_tdm.o
--- /dev/null
+++ b/sound/soc/starfive/jh7110_spdif.c
@@ -0,0 +1,568 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPDIF driver for the StarFive JH7110 SoC
+ *
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ */
+
+#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/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.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>
+
+#include "jh7110_spdif.h"
+
+static irqreturn_t spdif_irq_handler(int irq, void *dev_id)
+{
+	struct sf_spdif_dev *dev = dev_id;
+	bool irq_valid = false;
+	unsigned int intr;
+	unsigned int stat;
+
+	regmap_read(dev->regmap, SPDIF_INT_REG, &intr);
+	regmap_read(dev->regmap, SPDIF_STAT_REG, &stat);
+	regmap_update_bits(dev->regmap, SPDIF_CTRL, SPDIF_MASK_ENABLE, 0);
+	regmap_update_bits(dev->regmap, SPDIF_INT_REG, SPDIF_INT_REG_BIT, 0);
+
+	if ((stat & SPDIF_EMPTY_FLAG) || (stat & SPDIF_AEMPTY_FLAG)) {
+		sf_spdif_pcm_push_tx(dev);
+		irq_valid = true;
+	}
+
+	if ((stat & SPDIF_FULL_FLAG) || (stat & SPDIF_AFULL_FLAG)) {
+		sf_spdif_pcm_pop_rx(dev);
+		irq_valid = true;
+	}
+
+	if (stat & SPDIF_PARITY_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_UNDERR_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_OVRERR_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_SYNCERR_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_LOCK_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_BEGIN_FLAG)
+		irq_valid = true;
+
+	if (stat & SPDIF_RIGHT_LEFT)
+		irq_valid = true;
+
+	regmap_update_bits(dev->regmap, SPDIF_CTRL,
+		SPDIF_MASK_ENABLE, SPDIF_MASK_ENABLE);
+
+	if (irq_valid)
+		return IRQ_HANDLED;
+	else
+		return IRQ_NONE;
+}
+
+static int sf_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+			    struct snd_soc_dai *dai)
+{
+	struct sf_spdif_dev *spdif = snd_soc_dai_get_drvdata(dai);
+	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
+
+	if (tx) {
+		/* tx mode */
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_TR_MODE, SPDIF_TR_MODE);
+
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_MASK_FIFO, SPDIF_EMPTY_MASK | SPDIF_AEMPTY_MASK);
+	} else {
+		/* rx mode */
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_TR_MODE, 0);
+
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_MASK_FIFO, SPDIF_FULL_MASK | SPDIF_AFULL_MASK);
+	}
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		/* clock recovery form the SPDIF data stream  0:clk_enable */
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_CLK_ENABLE, 0);
+
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_ENABLE, SPDIF_ENABLE);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		/* clock recovery form the SPDIF data stream  1:power save mode */
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_CLK_ENABLE, SPDIF_CLK_ENABLE);
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_ENABLE, 0);
+		break;
+	default:
+		dev_err(dai->dev, "%s L.%d cmd:%d\n", __func__, __LINE__, cmd);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int sf_spdif_hw_params(struct snd_pcm_substream *substream,
+			      struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+	struct sf_spdif_dev *spdif = snd_soc_dai_get_drvdata(dai);
+	unsigned int channels = params_channels(params);
+	unsigned int rate = params_rate(params);
+	unsigned int format = params_format(params);
+	unsigned int tsamplerate;
+	unsigned int mclk;
+	unsigned int audio_root;
+	int ret;
+
+	switch (channels) {
+	case 1:
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_CHANNEL_MODE, SPDIF_CHANNEL_MODE);
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_DUPLICATE, SPDIF_DUPLICATE);
+		spdif->channels = false;
+		break;
+	case 2:
+		regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+				   SPDIF_CHANNEL_MODE, 0);
+		spdif->channels = true;
+		break;
+	default:
+		dev_err(dai->dev, "invalid channels number\n");
+		return -EINVAL;
+	}
+
+	switch (format) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+	case SNDRV_PCM_FORMAT_S24_LE:
+	case SNDRV_PCM_FORMAT_S24_3LE:
+	case SNDRV_PCM_FORMAT_S32_LE:
+		break;
+	default:
+		dev_err(dai->dev, "invalid format\n");
+		return -EINVAL;
+	}
+
+	switch (rate) {
+	case 8000:
+		break;
+	case 11025:
+		audio_root = 148500000;
+		/* 11025 * 512 = 5644800 */
+		/* But now pll2 is 1188m and mclk should be 5711539 closely. */
+		mclk = 5711539;
+		break;
+	case 16000:
+		break;
+	case 22050:
+		audio_root = 148500000;
+		mclk = 11423077;
+		break;
+	default:
+		dev_err(dai->dev, "channel:%d sample rate:%d\n", channels, rate);
+		return -EINVAL;
+	}
+
+	/* use mclk_inner clock from 1188m PLL2 will be better about 11k and 22k*/
+	if ((rate == 11025) || (rate == 22050)) {
+		ret = clk_set_parent(spdif->mclk, spdif->mclk_inner);
+		if (ret) {
+			dev_err(dai->dev,
+				"failed to set parent to mclk_inner ret=%d\n", ret);
+			goto fail_ext;
+		}
+
+		ret = clk_set_rate(spdif->audio_root, audio_root);
+		if (ret) {
+			dev_err(dai->dev, "failed to set audio_root rate :%d\n", ret);
+			goto fail_ext;
+		}
+
+		ret = clk_set_rate(spdif->mclk_inner, mclk);
+		if (ret) {
+			dev_err(dai->dev, "failed to set mclk_inner rate :%d\n", ret);
+			goto fail_ext;
+		}
+
+		mclk = clk_get_rate(spdif->mclk_inner);
+	} else {
+		ret = clk_set_parent(spdif->mclk, spdif->mclk_ext);
+		if (ret) {
+			dev_err(dai->dev,
+				"failed to set parent to mclk_ext ret=%d\n", ret);
+			goto fail_ext;
+		}
+
+		mclk = clk_get_rate(spdif->mclk_ext);
+	}
+
+	/* (FCLK)4096000/128=32000 */
+	tsamplerate = (mclk / 128 + rate / 2) / rate - 1;
+	if (tsamplerate < 3)
+		tsamplerate = 3;
+
+	/* transmission sample rate */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL, 0xFF, tsamplerate);
+
+	return 0;
+
+fail_ext:
+	return ret;
+}
+
+static int sf_spdif_clks_get(struct platform_device *pdev,
+			     struct sf_spdif_dev *spdif)
+{
+	static struct clk_bulk_data clks[] = {
+		{ .id = "apb" },		/* clock-names in dts file */
+		{ .id = "core" },
+		{ .id = "audroot" },
+		{ .id = "mclk_inner"},
+		{ .id = "mclk_ext"},
+		{ .id = "mclk"},
+	};
+	int ret = devm_clk_bulk_get(&pdev->dev, ARRAY_SIZE(clks), clks);
+
+	spdif->spdif_apb = clks[0].clk;
+	spdif->spdif_core = clks[1].clk;
+	spdif->audio_root = clks[2].clk;
+	spdif->mclk_inner = clks[3].clk;
+	spdif->mclk_ext = clks[4].clk;
+	spdif->mclk = clks[5].clk;
+
+	return ret;
+}
+
+static int sf_spdif_resets_get(struct platform_device *pdev,
+			       struct sf_spdif_dev *spdif)
+{
+	struct reset_control_bulk_data resets[] = {
+			{ .id = "apb" },
+	};
+	int ret = devm_reset_control_bulk_get_exclusive(&pdev->dev, ARRAY_SIZE(resets), resets);
+
+	if (ret)
+		return ret;
+
+	spdif->rst_apb = resets[0].rstc;
+
+	return 0;
+}
+
+static int starfive_spdif_crg_enable(struct sf_spdif_dev *spdif, bool enable)
+{
+	int ret;
+
+	dev_dbg(spdif->dev, "starfive_spdif clk&rst %sable.\n", enable ? "en":"dis");
+	if (enable) {
+		ret = clk_prepare_enable(spdif->spdif_apb);
+		if (ret) {
+			dev_err(spdif->dev, "failed to prepare enable spdif_apb\n");
+			goto failed_apb_clk;
+		}
+
+		ret = clk_prepare_enable(spdif->spdif_core);
+		if (ret) {
+			dev_err(spdif->dev, "failed to prepare enable spdif_core\n");
+			goto failed_core_clk;
+		}
+
+		ret = reset_control_deassert(spdif->rst_apb);
+		if (ret) {
+			dev_err(spdif->dev, "failed to deassert apb\n");
+			goto failed_rst;
+		}
+	} else {
+		clk_disable_unprepare(spdif->spdif_core);
+		clk_disable_unprepare(spdif->spdif_apb);
+	}
+
+	return 0;
+
+failed_rst:
+	clk_disable_unprepare(spdif->spdif_core);
+failed_core_clk:
+	clk_disable_unprepare(spdif->spdif_apb);
+failed_apb_clk:
+	return ret;
+}
+
+static int sf_spdif_dai_probe(struct snd_soc_dai *dai)
+{
+	struct sf_spdif_dev *spdif = snd_soc_dai_get_drvdata(dai);
+
+	pm_runtime_get_sync(spdif->dev);
+
+	/* reset */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_ENABLE | SPDIF_SFR_ENABLE | SPDIF_FIFO_ENABLE, 0);
+
+	/* clear irq */
+	regmap_update_bits(spdif->regmap, SPDIF_INT_REG,
+			   SPDIF_INT_REG_BIT, 0);
+
+	/* power save mode */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_CLK_ENABLE, SPDIF_CLK_ENABLE);
+
+	/* power save mode */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_CLK_ENABLE, SPDIF_CLK_ENABLE);
+
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_PARITCHECK|SPDIF_VALIDITYCHECK|SPDIF_DUPLICATE,
+			   SPDIF_PARITCHECK|SPDIF_VALIDITYCHECK|SPDIF_DUPLICATE);
+
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_SETPREAMBB, SPDIF_SETPREAMBB);
+
+	regmap_update_bits(spdif->regmap, SPDIF_INT_REG,
+			   BIT8TO20MASK<<SPDIF_PREAMBLEDEL, 0x3<<SPDIF_PREAMBLEDEL);
+
+	regmap_update_bits(spdif->regmap, SPDIF_FIFO_CTRL,
+			   ALLBITMASK, 0x20|(0x20<<SPDIF_AFULL_THRESHOLD));
+
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_PARITYGEN, SPDIF_PARITYGEN);
+
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_MASK_ENABLE, SPDIF_MASK_ENABLE);
+
+	/* APB access to FIFO enable, disable if use DMA/FIFO */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_USE_FIFO_IF, 0);
+
+	/* two channel */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   SPDIF_CHANNEL_MODE, 0);
+
+	pm_runtime_put_sync(spdif->dev);
+	return 0;
+}
+
+static const struct snd_soc_dai_ops sf_spdif_dai_ops = {
+	.probe = sf_spdif_dai_probe,
+	.trigger = sf_spdif_trigger,
+	.hw_params = sf_spdif_hw_params,
+};
+
+#ifdef CONFIG_PM_SLEEP
+static int spdif_system_suspend(struct device *dev)
+{
+	struct sf_spdif_dev *spdif = dev_get_drvdata(dev);
+
+	/* save the register value */
+	regmap_read(spdif->regmap, SPDIF_CTRL, &spdif->reg_spdif_ctrl);
+	regmap_read(spdif->regmap, SPDIF_INT_REG, &spdif->reg_spdif_int);
+	regmap_read(spdif->regmap, SPDIF_FIFO_CTRL, &spdif->reg_spdif_fifo_ctrl);
+
+	return pm_runtime_force_suspend(dev);
+}
+
+static int spdif_system_resume(struct device *dev)
+{
+	struct sf_spdif_dev *spdif = dev_get_drvdata(dev);
+	int ret = pm_runtime_force_resume(dev);
+
+	if (ret)
+		return ret;
+
+	/* restore the register value */
+	regmap_update_bits(spdif->regmap, SPDIF_CTRL,
+			   ALLBITMASK, spdif->reg_spdif_ctrl);
+	regmap_update_bits(spdif->regmap, SPDIF_INT_REG,
+			   ALLBITMASK, spdif->reg_spdif_int);
+	regmap_update_bits(spdif->regmap, SPDIF_FIFO_CTRL,
+			   ALLBITMASK, spdif->reg_spdif_fifo_ctrl);
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int spdif_runtime_suspend(struct device *dev)
+{
+	struct sf_spdif_dev *spdif = dev_get_drvdata(dev);
+
+	return starfive_spdif_crg_enable(spdif, false);
+}
+
+static int spdif_runtime_resume(struct device *dev)
+{
+	struct sf_spdif_dev *spdif = dev_get_drvdata(dev);
+
+	return starfive_spdif_crg_enable(spdif, true);
+}
+#endif
+
+static const struct dev_pm_ops spdif_pm_ops = {
+	SET_RUNTIME_PM_OPS(spdif_runtime_suspend, spdif_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(spdif_system_suspend, spdif_system_resume)
+};
+
+#define SF_PCM_RATE_44100_192000 (SNDRV_PCM_RATE_44100 | \
+				  SNDRV_PCM_RATE_48000 | \
+				  SNDRV_PCM_RATE_96000 | \
+				  SNDRV_PCM_RATE_192000)
+
+#define SF_PCM_RATE_8000_22050 (SNDRV_PCM_RATE_8000 | \
+				SNDRV_PCM_RATE_11025 | \
+				SNDRV_PCM_RATE_16000 | \
+				SNDRV_PCM_RATE_22050)
+
+static struct snd_soc_dai_driver sf_spdif_dai = {
+	.name = "spdif",
+	.id = 0,
+	.playback = {
+		.stream_name = "Playback",
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = SF_PCM_RATE_8000_22050,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE |
+			   SNDRV_PCM_FMTBIT_S24_LE |
+			   SNDRV_PCM_FMTBIT_S24_3LE |
+			   SNDRV_PCM_FMTBIT_S32_LE,
+	},
+	.ops = &sf_spdif_dai_ops,
+	.symmetric_rate = 1,
+};
+
+static const struct snd_soc_component_driver sf_spdif_component = {
+	.name = "starfive-spdif",
+};
+
+static const struct regmap_config sf_spdif_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.max_register = 0x200,
+};
+
+static int sf_spdif_probe(struct platform_device *pdev)
+{
+	struct sf_spdif_dev *spdif;
+	struct resource *res;
+	void __iomem *base;
+	int ret;
+	int irq;
+
+	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
+	if (!spdif)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, spdif);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	spdif->spdif_base = base;
+	spdif->regmap = devm_regmap_init_mmio(&pdev->dev, spdif->spdif_base,
+					      &sf_spdif_regmap_config);
+	if (IS_ERR(spdif->regmap))
+		return PTR_ERR(spdif->regmap);
+
+	spdif->dev = &pdev->dev;
+
+	ret = sf_spdif_clks_get(pdev, spdif);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to get audio clock\n");
+		return ret;
+	}
+
+	ret = sf_spdif_resets_get(pdev, spdif);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to get audio reset controls\n");
+		return ret;
+	}
+
+	ret = starfive_spdif_crg_enable(spdif, true);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable audio clock\n");
+		return ret;
+	}
+
+	spdif->fifo_th = 16;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq >= 0) {
+		ret = devm_request_irq(&pdev->dev, irq, spdif_irq_handler, 0,
+				pdev->name, spdif);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "failed to request irq\n");
+			return ret;
+		}
+	}
+
+	ret = devm_snd_soc_register_component(&pdev->dev, &sf_spdif_component,
+					 &sf_spdif_dai, 1);
+	if (ret)
+		goto err_clk_disable;
+
+	if (irq >= 0) {
+		ret = sf_spdif_pcm_register(pdev);
+		spdif->use_pio = true;
+	} else {
+		ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL,
+					0);
+		spdif->use_pio = false;
+	}
+
+	if (ret)
+		goto err_clk_disable;
+
+	starfive_spdif_crg_enable(spdif, false);
+	pm_runtime_enable(&pdev->dev);
+	dev_dbg(&pdev->dev, "spdif register done.\n");
+
+	return 0;
+
+err_clk_disable:
+	return ret;
+}
+
+static const struct of_device_id sf_spdif_of_match[] = {
+	{ .compatible = "starfive,jh7110-spdif", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sf_spdif_of_match);
+
+static struct platform_driver sf_spdif_driver = {
+	.driver = {
+		.name = "starfive-spdif",
+		.of_match_table = sf_spdif_of_match,
+		.pm = &spdif_pm_ops,
+	},
+	.probe = sf_spdif_probe,
+};
+module_platform_driver(sf_spdif_driver);
+
+MODULE_AUTHOR("curry.zhang <curry.zhang@starfive.com>");
+MODULE_AUTHOR("Xingyu Wu <xingyu.wu@starfivetech.com>");
+MODULE_DESCRIPTION("starfive SPDIF driver");
+MODULE_LICENSE("GPL v2");
--- /dev/null
+++ b/sound/soc/starfive/jh7110_spdif.h
@@ -0,0 +1,196 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * SPDIF driver for the StarFive JH7110 SoC
+ *
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ */
+
+#ifndef __SND_SOC_JH7110_SPDIF_H
+#define __SND_SOC_JH7110_SPDIF_H
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/types.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/pcm.h>
+
+#define SPDIF_CTRL			0x0
+#define SPDIF_INT_REG			0x4
+#define SPDIF_FIFO_CTRL			0x8
+#define SPDIF_STAT_REG			0xC
+
+#define SPDIF_FIFO_ADDR			0x100
+#define DMAC_SPDIF_POLLING_LEN		256
+
+/* ctrl: sampled on the rising clock edge */
+#define	SPDIF_TSAMPLERATE	0	/* [SRATEW-1:0] */
+/* 0:SFR reg reset to defualt value; auto set back to '1' after reset */
+#define SPDIF_SFR_ENABLE	(1<<8)
+/* 0:reset of SPDIF block, SRF bits are unchanged; 1:enables SPDIF module */
+#define SPDIF_ENABLE		(1<<9)
+/* 0:FIFO pointers are reset to zero,threshold levels for FIFO are unchaned; auto set back to 1 */
+#define SPDIF_FIFO_ENABLE	(1<<10)
+/* 1:blocked and the modules are in power save mode; 0:block feeds the modules */
+#define SPDIF_CLK_ENABLE	(1<<11)
+#define SPDIF_TR_MODE		(1<<12)	/* 0:rx; 1:tx */
+/* 0:party bit rx in a sub-frame is repeated on the parity; 1:check on a parity error */
+#define SPDIF_PARITCHECK	(1<<13)
+/*
+ * 0:parity bit from FIFO is transmitted in sub-frame;
+ * 1:parity bit generated inside the core and added to a transmitted sub-frame
+ */
+#define SPDIF_PARITYGEN		(1<<14)
+/* 0:validity bit in frame isn't checked and all frame are written; 1:validity bit rx is checked */
+#define SPDIF_VALIDITYCHECK	(1<<15)
+#define SPDIF_CHANNEL_MODE	(1<<16)	/* 0:two-channel; 1:single-channel */
+/* only tx -single-channel mode; 0:secondary channel; 1: left(primary) channel */
+#define SPDIF_DUPLICATE		(1<<17)
+/*
+ * only tx;
+ * 0:first preamble B after reset tx valid sub-frame;
+ * 1:first preamble B is tx after preambleddel(INT_REG)
+ */
+#define SPDIF_SETPREAMBB	(1<<18)
+/* 0:FIFO disabled ,APB accese FIFO; 1:FIFO enable, APB access to FIFO disable; */
+#define SPDIF_USE_FIFO_IF	(1<<19)
+#define SPDIF_PARITY_MASK	(1<<21)
+#define SPDIF_UNDERR_MASK	(1<<22)
+#define SPDIF_OVRERR_MASK	(1<<23)
+#define SPDIF_EMPTY_MASK	(1<<24)
+#define	SPDIF_AEMPTY_MASK	(1<<25)
+#define SPDIF_FULL_MASK		(1<<26)
+#define SPDIF_AFULL_MASK	(1<<27)
+#define SPDIF_SYNCERR_MASK	(1<<28)
+#define SPDIF_LOCK_MASK		(1<<29)
+#define SPDIF_BEGIN_MASK	(1<<30)
+#define SPDIF_INTEREQ_MAKS	(1<<31)
+
+#define SPDIF_MASK_ENABLE	(SPDIF_PARITY_MASK | SPDIF_UNDERR_MASK | \
+				 SPDIF_OVRERR_MASK | SPDIF_EMPTY_MASK | \
+				 SPDIF_AEMPTY_MASK | SPDIF_FULL_MASK | \
+				 SPDIF_AFULL_MASK | SPDIF_SYNCERR_MASK | \
+				 SPDIF_LOCK_MASK | SPDIF_BEGIN_MASK | \
+				 SPDIF_INTEREQ_MAKS)
+
+#define SPDIF_MASK_FIFO	(SPDIF_EMPTY_MASK | SPDIF_AEMPTY_MASK | \
+			 SPDIF_FULL_MASK | SPDIF_AFULL_MASK)
+
+/* INT_REG */
+#define SPDIF_RSAMPLERATE	0	/* [SRATEW-1:0] */
+#define SPDIF_PREAMBLEDEL	8	/* [PDELAYW+7:8] first B delay */
+#define SPDIF_PARITYO		(1<<21)	/* 0:clear parity error */
+#define SPDIF_TDATA_UNDERR	(1<<22)	/* tx data underrun error;0:clear */
+#define SPDIF_RDATA_OVRERR	(1<<23)	/* rx data overrun error; 0:clear */
+#define SPDIF_FIFO_EMPTY	(1<<24)	/* empty; 0:clear */
+#define SPDIF_FIOF_AEMPTY	(1<<25)	/* almost empty; 0:clear */
+#define SPDIF_FIFO_FULL		(1<<26)	/* FIFO full; 0:clear */
+#define SPDIF_FIFO_AFULL	(1<<27)	/* FIFO almost full; 0:clear */
+#define SPDIF_SYNCERR		(1<<28)	/* sync error; 0:clear */
+#define SPDIF_LOCK		(1<<29)	/* sync; 0:clear */
+#define SPDIF_BLOCK_BEGIN	(1<<30)	/* new start block rx data */
+
+#define SPDIF_INT_REG_BIT	(SPDIF_PARITYO | SPDIF_TDATA_UNDERR | \
+				 SPDIF_RDATA_OVRERR | SPDIF_FIFO_EMPTY | \
+				 SPDIF_FIOF_AEMPTY | SPDIF_FIFO_FULL | \
+				 SPDIF_FIFO_AFULL | SPDIF_SYNCERR | \
+				 SPDIF_LOCK | SPDIF_BLOCK_BEGIN)
+
+#define SPDIF_ERROR_INT_STATUS	(SPDIF_PARITYO | \
+				 SPDIF_TDATA_UNDERR | SPDIF_RDATA_OVRERR)
+#define SPDIF_FIFO_INT_STATUS	(SPDIF_FIFO_EMPTY | SPDIF_FIOF_AEMPTY | \
+				 SPDIF_FIFO_FULL | SPDIF_FIFO_AFULL)
+
+#define SPDIF_INT_PARITY_ERROR	(-1)
+#define SPDIF_INT_TDATA_UNDERR	(-2)
+#define SPDIF_INT_RDATA_OVRERR	(-3)
+#define SPDIF_INT_FIFO_EMPTY	1
+#define SPDIF_INT_FIFO_AEMPTY	2
+#define SPDIF_INT_FIFO_FULL	3
+#define SPDIF_INT_FIFO_AFULL	4
+#define SPDIF_INT_SYNCERR	(-4)
+#define SPDIF_INT_LOCK		5 /* reciever has become synchronized with input data stream */
+#define SPDIF_INT_BLOCK_BEGIN	6 /* start a new block in recieve data, written into FIFO */
+
+/* FIFO_CTRL */
+#define SPDIF_AEMPTY_THRESHOLD	0	/* [depth-1:0] */
+#define SPDIF_AFULL_THRESHOLD	16	/* [depth+15:16] */
+
+/* STAT_REG */
+#define SPDIF_FIFO_LEVEL	(1<<0)
+#define SPDIF_PARITY_FLAG	(1<<21)	/* 1:error; 0:repeated */
+#define SPDIF_UNDERR_FLAG	(1<<22)	/* 1:error */
+#define SPDIF_OVRERR_FLAG	(1<<23)	/* 1:error */
+#define SPDIF_EMPTY_FLAG	(1<<24)	/* 1:fifo empty */
+#define SPDIF_AEMPTY_FLAG	(1<<25)	/* 1:fifo almost empty */
+#define SPDIF_FULL_FLAG		(1<<26)	/* 1:fifo full */
+#define SPDIF_AFULL_FLAG	(1<<27)	/* 1:fifo almost full */
+#define SPDIF_SYNCERR_FLAG	(1<<28)	/* 1:rx sync error */
+#define SPDIF_LOCK_FLAG		(1<<29)	/* 1:RX sync */
+#define SPDIF_BEGIN_FLAG	(1<<30)	/* 1:start a new block */
+/* 1:left channel received and tx into FIFO; 0:right channel received and tx into FIFO */
+#define SPDIF_RIGHT_LEFT	(1<<31)
+
+#define BIT8TO20MASK	0x1FFF
+#define ALLBITMASK		0xFFFFFFFF
+
+#define SPDIF_STAT		(SPDIF_PARITY_FLAG | SPDIF_UNDERR_FLAG | \
+				 SPDIF_OVRERR_FLAG | SPDIF_EMPTY_FLAG | \
+				 SPDIF_AEMPTY_FLAG | SPDIF_FULL_FLAG | \
+				 SPDIF_AFULL_FLAG | SPDIF_SYNCERR_FLAG | \
+				 SPDIF_LOCK_FLAG | SPDIF_BEGIN_FLAG | \
+				 SPDIF_RIGHT_LEFT)
+struct sf_spdif_dev {
+	void __iomem *spdif_base;
+	struct regmap *regmap;
+	struct device *dev;
+	u32 fifo_th;
+	int active;
+
+	/* data related to DMA transfers b/w i2s and DMAC */
+	struct snd_dmaengine_dai_dma_data play_dma_data;
+	struct snd_dmaengine_dai_dma_data capture_dma_data;
+
+	bool use_pio;
+	struct snd_pcm_substream __rcu *tx_substream;
+	struct snd_pcm_substream __rcu *rx_substream;
+
+	unsigned int (*tx_fn)(struct sf_spdif_dev *dev,
+			      struct snd_pcm_runtime *runtime, unsigned int tx_ptr,
+			      bool *period_elapsed, snd_pcm_format_t format);
+	unsigned int (*rx_fn)(struct sf_spdif_dev *dev,
+			      struct snd_pcm_runtime *runtime, unsigned int rx_ptr,
+			      bool *period_elapsed, snd_pcm_format_t format);
+
+	snd_pcm_format_t format;
+	bool channels;
+	unsigned int tx_ptr;
+	unsigned int rx_ptr;
+	struct clk *spdif_apb;
+	struct clk *spdif_core;
+	struct clk *audio_root;
+	struct clk *mclk_inner;
+	struct clk *mclk;
+	struct clk *mclk_ext;
+	struct reset_control *rst_apb;
+	unsigned int reg_spdif_ctrl;
+	unsigned int reg_spdif_int;
+	unsigned int reg_spdif_fifo_ctrl;
+
+	struct snd_dmaengine_dai_dma_data dma_data;
+};
+
+#if IS_ENABLED(CONFIG_SND_SOC_JH7110_SPDIF_PCM)
+void sf_spdif_pcm_push_tx(struct sf_spdif_dev *dev);
+void sf_spdif_pcm_pop_rx(struct sf_spdif_dev *dev);
+int sf_spdif_pcm_register(struct platform_device *pdev);
+#else
+void sf_spdif_pcm_push_tx(struct sf_spdif_dev *dev) { }
+void sf_spdif_pcm_pop_rx(struct sf_spdif_dev *dev) { }
+int sf_spdif_pcm_register(struct platform_device *pdev)
+{
+	return -EINVAL;
+}
+#endif
+
+#endif	/* __SND_SOC_JH7110_SPDIF_H */
--- /dev/null
+++ b/sound/soc/starfive/jh7110_spdif_pcm.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SPDIF PCM driver for the StarFive JH7110 SoC
+ *
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ */
+
+#include <linux/io.h>
+#include <linux/rcupdate.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "jh7110_spdif.h"
+
+#define BUFFER_BYTES_MAX	(3 * 2 * 8 * PERIOD_BYTES_MIN)
+#define PERIOD_BYTES_MIN	4096
+#define PERIODS_MIN		2
+
+static unsigned int sf_spdif_pcm_tx(struct sf_spdif_dev *dev,
+				    struct snd_pcm_runtime *runtime, unsigned int tx_ptr,
+				    bool *period_elapsed, snd_pcm_format_t format)
+{
+	unsigned int period_pos = tx_ptr % runtime->period_size;
+	u32 data[2];
+	int i;
+
+	/* two- channel and signal-channel mode */
+	if (dev->channels) {
+		const u16 (*p16)[2] = (void *)runtime->dma_area;
+		const u32 (*p32)[2] = (void *)runtime->dma_area;
+
+		for (i = 0; i < dev->fifo_th; i++) {
+			if (format == SNDRV_PCM_FORMAT_S16_LE) {
+				data[0] = p16[tx_ptr][0];
+				data[0] = data[0]<<8;
+				data[0] &= 0x00ffff00;
+				data[1] = p16[tx_ptr][1];
+				data[1] = data[1]<<8;
+				data[1] &= 0x00ffff00;
+			} else if (format == SNDRV_PCM_FORMAT_S24_LE) {
+				data[0] = p32[tx_ptr][0];
+				data[1] = p32[tx_ptr][1];
+
+				/*
+				 * To adapt S24_3LE and ALSA pass parameter of S24_LE.
+				 * operation of S24_LE should be same to S24_3LE.
+				 * So it would wrong when playback S24_LE file.
+				 * when want to playback S24_LE file, should add in there:
+				 * data[0] = data[0]>>8;
+				 * data[1] = data[1]>>8;
+				 */
+
+				data[0] &= 0x00ffffff;
+				data[1] &= 0x00ffffff;
+			} else if (format == SNDRV_PCM_FORMAT_S24_3LE) {
+				data[0] = p32[tx_ptr][0];
+				data[1] = p32[tx_ptr][1];
+				data[0] &= 0x00ffffff;
+				data[1] &= 0x00ffffff;
+			} else if (format == SNDRV_PCM_FORMAT_S32_LE) {
+				data[0] = p32[tx_ptr][0];
+				data[0] = data[0]>>8;
+				data[1] = p32[tx_ptr][1];
+				data[1] = data[1]>>8;
+			}
+
+			iowrite32(data[0], dev->spdif_base + SPDIF_FIFO_ADDR);
+			iowrite32(data[1], dev->spdif_base + SPDIF_FIFO_ADDR);
+			period_pos++;
+			if (++tx_ptr >= runtime->buffer_size)
+				tx_ptr = 0;
+		}
+	} else {
+		const u16 (*p16) = (void *)runtime->dma_area;
+		const u32 (*p32) = (void *)runtime->dma_area;
+
+		for (i = 0; i < dev->fifo_th; i++) {
+			if (format == SNDRV_PCM_FORMAT_S16_LE) {
+				data[0] = p16[tx_ptr];
+				data[0] = data[0]<<8;
+				data[0] &= 0x00ffff00;
+			} else if (format == SNDRV_PCM_FORMAT_S24_LE ||
+				format == SNDRV_PCM_FORMAT_S24_3LE) {
+				data[0] = p32[tx_ptr];
+				data[0] &= 0x00ffffff;
+			} else if (format == SNDRV_PCM_FORMAT_S32_LE) {
+				data[0] = p32[tx_ptr];
+				data[0] = data[0]>>8;
+			}
+
+			iowrite32(data[0], dev->spdif_base + SPDIF_FIFO_ADDR);
+			period_pos++;
+			if (++tx_ptr >= runtime->buffer_size)
+				tx_ptr = 0;
+		}
+	}
+
+	*period_elapsed = period_pos >= runtime->period_size;
+	return tx_ptr;
+}
+
+static unsigned int sf_spdif_pcm_rx(struct sf_spdif_dev *dev,
+				    struct snd_pcm_runtime *runtime, unsigned int rx_ptr,
+				    bool *period_elapsed, snd_pcm_format_t format)
+{
+	u16 (*p16)[2] = (void *)runtime->dma_area;
+	u32 (*p32)[2] = (void *)runtime->dma_area;
+	unsigned int period_pos = rx_ptr % runtime->period_size;
+	u32 data[2];
+	int i;
+
+	for (i = 0; i < dev->fifo_th; i++) {
+		data[0] = ioread32(dev->spdif_base + SPDIF_FIFO_ADDR);
+		data[1] = ioread32(dev->spdif_base + SPDIF_FIFO_ADDR);
+		if (format == SNDRV_PCM_FORMAT_S16_LE) {
+			p16[rx_ptr][0] = data[0]>>8;
+			p16[rx_ptr][1] = data[1]>>8;
+		} else if (format == SNDRV_PCM_FORMAT_S24_LE) {
+			p32[rx_ptr][0] = data[0];
+			p32[rx_ptr][1] = data[1];
+		} else if (format == SNDRV_PCM_FORMAT_S32_LE) {
+			p32[rx_ptr][0] = data[0]<<8;
+			p32[rx_ptr][1] = data[1]<<8;
+		}
+
+		period_pos++;
+		if (++rx_ptr >= runtime->buffer_size)
+			rx_ptr = 0;
+	}
+
+	*period_elapsed = period_pos >= runtime->period_size;
+	return rx_ptr;
+}
+
+static const struct snd_pcm_hardware sf_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_BLOCK_TRANSFER |
+		SNDRV_PCM_INFO_PAUSE |
+		SNDRV_PCM_INFO_RESUME,
+	.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,
+	.rate_min = 8000,
+	.rate_max = 48000,
+	.formats = SNDRV_PCM_FMTBIT_S16_LE |
+		SNDRV_PCM_FMTBIT_S24_LE |
+		SNDRV_PCM_FMTBIT_S24_3LE |
+		SNDRV_PCM_FMTBIT_S32_LE,
+	.channels_min = 1,
+	.channels_max = 2,
+	.buffer_bytes_max = BUFFER_BYTES_MAX,
+	.period_bytes_min = PERIOD_BYTES_MIN,
+	.period_bytes_max = BUFFER_BYTES_MAX / PERIODS_MIN,
+	.periods_min = PERIODS_MIN,
+	.periods_max = BUFFER_BYTES_MAX / PERIOD_BYTES_MIN,
+	.fifo_size = 16,
+};
+
+static void sf_spdif_pcm_transfer(struct sf_spdif_dev *dev, bool push)
+{
+	struct snd_pcm_substream *substream;
+	bool active, period_elapsed;
+
+	rcu_read_lock();
+	if (push)
+		substream = rcu_dereference(dev->tx_substream);
+	else
+		substream = rcu_dereference(dev->rx_substream);
+
+	active = substream && snd_pcm_running(substream);
+	if (active) {
+		unsigned int ptr;
+		unsigned int new_ptr;
+
+		if (push) {
+			ptr = READ_ONCE(dev->tx_ptr);
+			new_ptr = dev->tx_fn(dev, substream->runtime, ptr,
+					&period_elapsed, dev->format);
+			cmpxchg(&dev->tx_ptr, ptr, new_ptr);
+		} else {
+			ptr = READ_ONCE(dev->rx_ptr);
+			new_ptr = dev->rx_fn(dev, substream->runtime, ptr,
+					&period_elapsed, dev->format);
+			cmpxchg(&dev->rx_ptr, ptr, new_ptr);
+		}
+
+		if (period_elapsed)
+			snd_pcm_period_elapsed(substream);
+	}
+	rcu_read_unlock();
+}
+
+void sf_spdif_pcm_push_tx(struct sf_spdif_dev *dev)
+{
+	sf_spdif_pcm_transfer(dev, true);
+}
+
+void sf_spdif_pcm_pop_rx(struct sf_spdif_dev *dev)
+{
+	sf_spdif_pcm_transfer(dev, false);
+}
+
+static int sf_pcm_open(struct snd_soc_component *component,
+		       struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	struct sf_spdif_dev *dev = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
+
+	snd_soc_set_runtime_hwparams(substream, &sf_pcm_hardware);
+	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
+	runtime->private_data = dev;
+
+	return 0;
+}
+
+static int sf_pcm_close(struct snd_soc_component *component,
+			struct snd_pcm_substream *substream)
+{
+	synchronize_rcu();
+	return 0;
+}
+
+static int sf_pcm_hw_params(struct snd_soc_component *component,
+			    struct snd_pcm_substream *substream,
+			    struct snd_pcm_hw_params *hw_params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+
+	switch (params_channels(hw_params)) {
+	case 1:
+	case 2:
+		break;
+	default:
+		dev_err(dev->dev, "invalid channels number\n");
+		return -EINVAL;
+	}
+
+	dev->format = params_format(hw_params);
+	switch (dev->format) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+	case SNDRV_PCM_FORMAT_S24_LE:
+	case SNDRV_PCM_FORMAT_S24_3LE:
+	case SNDRV_PCM_FORMAT_S32_LE:
+		break;
+	default:
+		dev_err(dev->dev, "invalid format\n");
+		return -EINVAL;
+	}
+
+	dev->tx_fn = sf_spdif_pcm_tx;
+	dev->rx_fn = sf_spdif_pcm_rx;
+
+	return 0;
+}
+
+static int sf_pcm_trigger(struct snd_soc_component *component,
+			  struct snd_pcm_substream *substream, int cmd)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+			WRITE_ONCE(dev->tx_ptr, 0);
+			rcu_assign_pointer(dev->tx_substream, substream);
+		} else {
+			WRITE_ONCE(dev->rx_ptr, 0);
+			rcu_assign_pointer(dev->rx_substream, substream);
+		}
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			rcu_assign_pointer(dev->tx_substream, NULL);
+		else
+			rcu_assign_pointer(dev->rx_substream, NULL);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static snd_pcm_uframes_t sf_pcm_pointer(struct snd_soc_component *component,
+					struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct sf_spdif_dev *dev = runtime->private_data;
+	snd_pcm_uframes_t pos;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		pos = READ_ONCE(dev->tx_ptr);
+	else
+		pos = READ_ONCE(dev->rx_ptr);
+
+	return pos < runtime->buffer_size ? pos : 0;
+}
+
+static int sf_pcm_new(struct snd_soc_component *component,
+		      struct snd_soc_pcm_runtime *rtd)
+{
+	size_t size = sf_pcm_hardware.buffer_bytes_max;
+
+	snd_pcm_set_managed_buffer_all(rtd->pcm,
+			SNDRV_DMA_TYPE_CONTINUOUS,
+			NULL, size, size);
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver sf_pcm_component = {
+	.open		= sf_pcm_open,
+	.close		= sf_pcm_close,
+	.hw_params	= sf_pcm_hw_params,
+	.trigger	= sf_pcm_trigger,
+	.pointer	= sf_pcm_pointer,
+	.pcm_construct	= sf_pcm_new,
+};
+
+int sf_spdif_pcm_register(struct platform_device *pdev)
+{
+	return devm_snd_soc_register_component(&pdev->dev, &sf_pcm_component,
+					       NULL, 0);
+}