ASoC: zx: Add zx296702 SPDIF support

Add driver for zx296702 SPDIF controller

Signed-off-by: Jun Nie <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/Kconfig

···
 source "sound/soc/txx9/Kconfig"
 source "sound/soc/ux500/Kconfig"
 source "sound/soc/xtensa/Kconfig"
+source "sound/soc/zte/Kconfig"
 
 # Supported codecs
 source "sound/soc/codecs/Kconfig"

sound/soc/Makefile

···
 obj-$(CONFIG_SND_SOC)	+= txx9/
 obj-$(CONFIG_SND_SOC)	+= ux500/
 obj-$(CONFIG_SND_SOC)	+= xtensa/
+obj-$(CONFIG_SND_SOC)	+= zte/

sound/soc/zte/Kconfig

···
+config ZX296702_SPDIF
+	tristate "ZX296702 spdif"
+	depends on SOC_ZX296702 || COMPILE_TEST
+	depends on COMMON_CLK
+	select SND_SOC_GENERIC_DMAENGINE_PCM
+	help
+	  Say Y or M if you want to add support for codecs attached to the
+	  zx296702 spdif interface

sound/soc/zte/Makefile

···
+obj-$(CONFIG_ZX296702_SPDIF)	+= zx296702-spdif.o

sound/soc/zte/zx296702-spdif.c

···
+/*
+ * Copyright (C) 2015 Linaro
+ *
+ * Author: Jun Nie <[e-mail]>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <sound/asoundef.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 <sound/soc-dai.h>
+
+#define ZX_CTRL				0x04
+#define ZX_FIFOCTRL			0x08
+#define ZX_INT_STATUS			0x10
+#define ZX_INT_MASK			0x14
+#define ZX_DATA				0x18
+#define ZX_VALID_BIT			0x1c
+#define ZX_CH_STA_1			0x20
+#define ZX_CH_STA_2			0x24
+#define ZX_CH_STA_3			0x28
+#define ZX_CH_STA_4			0x2c
+#define ZX_CH_STA_5			0x30
+#define ZX_CH_STA_6			0x34
+
+#define ZX_CTRL_MODA_16			(0 << 6)
+#define ZX_CTRL_MODA_18			BIT(6)
+#define ZX_CTRL_MODA_20			(2 << 6)
+#define ZX_CTRL_MODA_24			(3 << 6)
+#define ZX_CTRL_MODA_MASK		(3 << 6)
+
+#define ZX_CTRL_ENB			BIT(4)
+#define ZX_CTRL_DNB			(0 << 4)
+#define ZX_CTRL_ENB_MASK		BIT(4)
+
+#define ZX_CTRL_TX_OPEN			BIT(0)
+#define ZX_CTRL_TX_CLOSE		(0 << 0)
+#define ZX_CTRL_TX_MASK			BIT(0)
+
+#define ZX_CTRL_OPEN			(ZX_CTRL_TX_OPEN | ZX_CTRL_ENB)
+#define ZX_CTRL_CLOSE			(ZX_CTRL_TX_CLOSE | ZX_CTRL_DNB)
+
+#define ZX_CTRL_DOUBLE_TRACK		(0 << 8)
+#define ZX_CTRL_LEFT_TRACK		BIT(8)
+#define ZX_CTRL_RIGHT_TRACK		(2 << 8)
+#define ZX_CTRL_TRACK_MASK		(3 << 8)
+
+#define ZX_FIFOCTRL_TXTH_MASK		(0x1f << 8)
+#define ZX_FIFOCTRL_TXTH(x)		(x << 8)
+#define ZX_FIFOCTRL_TX_DMA_EN		BIT(2)
+#define ZX_FIFOCTRL_TX_DMA_DIS		(0 << 2)
+#define ZX_FIFOCTRL_TX_DMA_EN_MASK	BIT(2)
+#define ZX_FIFOCTRL_TX_FIFO_RST		BIT(0)
+#define ZX_FIFOCTRL_TX_FIFO_RST_MASK	BIT(0)
+
+#define ZX_VALID_DOUBLE_TRACK		(0 << 0)
+#define ZX_VALID_LEFT_TRACK		BIT(1)
+#define ZX_VALID_RIGHT_TRACK		(2 << 0)
+#define ZX_VALID_TRACK_MASK		(3 << 0)
+
+#define ZX_SPDIF_CLK_RAT		(4 * 32)
+
+struct zx_spdif_info {
+	struct snd_dmaengine_dai_dma_data	dma_data;
+	struct clk				*dai_clk;
+	void __iomem				*reg_base;
+	resource_size_t				mapbase;
+};
+
+static int zx_spdif_dai_probe(struct snd_soc_dai *dai)
+{
+	struct zx_spdif_info *zx_spdif = dev_get_drvdata(dai->dev);
+
+	snd_soc_dai_set_drvdata(dai, zx_spdif);
+	zx_spdif->dma_data.addr = zx_spdif->mapbase + ZX_DATA;
+	zx_spdif->dma_data.maxburst = 8;
+	snd_soc_dai_init_dma_data(dai, &zx_spdif->dma_data, NULL);
+	return 0;
+}
+
+static int zx_spdif_chanstats(void __iomem *base, unsigned int rate)
+{
+	u32 cstas1;
+
+	switch (rate) {
+	case 22050:
+		cstas1 = IEC958_AES3_CON_FS_22050;
+		break;
+	case 24000:
+		cstas1 = IEC958_AES3_CON_FS_24000;
+		break;
+	case 32000:
+		cstas1 = IEC958_AES3_CON_FS_32000;
+		break;
+	case 44100:
+		cstas1 = IEC958_AES3_CON_FS_44100;
+		break;
+	case 48000:
+		cstas1 = IEC958_AES3_CON_FS_48000;
+		break;
+	case 88200:
+		cstas1 = IEC958_AES3_CON_FS_88200;
+		break;
+	case 96000:
+		cstas1 = IEC958_AES3_CON_FS_96000;
+		break;
+	case 176400:
+		cstas1 = IEC958_AES3_CON_FS_176400;
+		break;
+	case 192000:
+		cstas1 = IEC958_AES3_CON_FS_192000;
+		break;
+	default:
+		return -EINVAL;
+	}
+	cstas1 = cstas1 << 24;
+	cstas1 |= IEC958_AES0_CON_NOT_COPYRIGHT;
+
+	writel_relaxed(cstas1, base + ZX_CH_STA_1);
+	return 0;
+}
+
+static int zx_spdif_hw_params(struct snd_pcm_substream *substream,
+			      struct snd_pcm_hw_params *params,
+			      struct snd_soc_dai *socdai)
+{
+	struct zx_spdif_info *zx_spdif = dev_get_drvdata(socdai->dev);
+	struct zx_spdif_info *spdif = snd_soc_dai_get_drvdata(socdai);
+	struct snd_dmaengine_dai_dma_data *dma_data = &zx_spdif->dma_data;
+	u32 val, ch_num, rate;
+	int ret;
+
+	dma_data = snd_soc_dai_get_dma_data(socdai, substream);
+	dma_data->addr_width = params_width(params) >> 3;
+
+	val = readl_relaxed(zx_spdif->reg_base + ZX_CTRL);
+	val &= ~ZX_CTRL_MODA_MASK;
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		val |= ZX_CTRL_MODA_16;
+		break;
+
+	case SNDRV_PCM_FORMAT_S18_3LE:
+		val |= ZX_CTRL_MODA_18;
+		break;
+
+	case SNDRV_PCM_FORMAT_S20_3LE:
+		val |= ZX_CTRL_MODA_20;
+		break;
+
+	case SNDRV_PCM_FORMAT_S24_LE:
+		val |= ZX_CTRL_MODA_24;
+		break;
+	default:
+		dev_err(socdai->dev, "Format not support!\n");
+		return -EINVAL;
+	}
+
+	ch_num = params_channels(params);
+	if (ch_num == 2)
+		val |= ZX_CTRL_DOUBLE_TRACK;
+	else
+		val |= ZX_CTRL_LEFT_TRACK;
+	writel_relaxed(val, zx_spdif->reg_base + ZX_CTRL);
+
+	val = readl_relaxed(zx_spdif->reg_base + ZX_VALID_BIT);
+	val &= ~ZX_VALID_TRACK_MASK;
+	if (ch_num == 2)
+		val |= ZX_VALID_DOUBLE_TRACK;
+	else
+		val |= ZX_VALID_RIGHT_TRACK;
+	writel_relaxed(val, zx_spdif->reg_base + ZX_VALID_BIT);
+
+	rate = params_rate(params);
+	ret = zx_spdif_chanstats(zx_spdif->reg_base, rate);
+	if (ret)
+		return ret;
+	ret = clk_set_rate(spdif->dai_clk, rate * ch_num * ZX_SPDIF_CLK_RAT);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static void zx_spdif_cfg_tx(void __iomem *base, int on)
+{
+	u32 val;
+
+	val = readl_relaxed(base + ZX_CTRL);
+	val &= ~(ZX_CTRL_ENB_MASK | ZX_CTRL_TX_MASK);
+	val |= on ? ZX_CTRL_OPEN : ZX_CTRL_CLOSE;
+	writel_relaxed(val, base + ZX_CTRL);
+
+	val = readl_relaxed(base + ZX_FIFOCTRL);
+	val &= ~ZX_FIFOCTRL_TX_DMA_EN_MASK;
+	if (on)
+		val |= ZX_FIFOCTRL_TX_DMA_EN;
+	writel_relaxed(val, base + ZX_FIFOCTRL);
+}
+
+static int zx_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+			    struct snd_soc_dai *dai)
+{
+	u32 val;
+	struct zx_spdif_info *zx_spdif = dev_get_drvdata(dai->dev);
+	int  ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		val = readl_relaxed(zx_spdif->reg_base + ZX_FIFOCTRL);
+		val |= ZX_FIFOCTRL_TX_FIFO_RST;
+		writel_relaxed(val, zx_spdif->reg_base + ZX_FIFOCTRL);
+	/* fall thru */
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		zx_spdif_cfg_tx(zx_spdif->reg_base, true);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		zx_spdif_cfg_tx(zx_spdif->reg_base, false);
+		break;
+
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int zx_spdif_startup(struct snd_pcm_substream *substream,
+			    struct snd_soc_dai *dai)
+{
+	struct zx_spdif_info *zx_spdif = dev_get_drvdata(dai->dev);
+
+	return clk_prepare_enable(zx_spdif->dai_clk);
+}
+
+static void zx_spdif_shutdown(struct snd_pcm_substream *substream,
+			      struct snd_soc_dai *dai)
+{
+	struct zx_spdif_info *zx_spdif = dev_get_drvdata(dai->dev);
+
+	clk_disable_unprepare(zx_spdif->dai_clk);
+}
+
+#define ZX_RATES \
+	(SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
+	SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |\
+	SNDRV_PCM_RATE_176400 | SNDRV_PCM_RATE_192000)
+
+#define ZX_FORMAT \
+	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S18_3LE \
+	| SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+static struct snd_soc_dai_ops zx_spdif_dai_ops = {
+	.trigger	= zx_spdif_trigger,
+	.startup	= zx_spdif_startup,
+	.shutdown	= zx_spdif_shutdown,
+	.hw_params	= zx_spdif_hw_params,
+};
+
+static struct snd_soc_dai_driver zx_spdif_dai = {
+	.name = "spdif",
+	.id = 0,
+	.probe = zx_spdif_dai_probe,
+	.playback = {
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = ZX_RATES,
+		.formats = ZX_FORMAT,
+	},
+	.ops = &zx_spdif_dai_ops,
+};
+
+static const struct snd_soc_component_driver zx_spdif_component = {
+	.name	= "spdif",
+};
+
+static void zx_spdif_dev_init(void __iomem *base)
+{
+	u32 val;
+
+	writel_relaxed(0, base + ZX_CTRL);
+	writel_relaxed(0, base + ZX_INT_MASK);
+	writel_relaxed(0xf, base + ZX_INT_STATUS);
+	writel_relaxed(0x1, base + ZX_FIFOCTRL);
+
+	val = readl_relaxed(base + ZX_FIFOCTRL);
+	val &= ~(ZX_FIFOCTRL_TXTH_MASK | ZX_FIFOCTRL_TX_FIFO_RST_MASK);
+	val |= ZX_FIFOCTRL_TXTH(8);
+	writel_relaxed(val, base + ZX_FIFOCTRL);
+}
+
+static int zx_spdif_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct zx_spdif_info *zx_spdif;
+	int ret;
+
+	zx_spdif = devm_kzalloc(sizeof(*zx_spdif), GFP_KERNEL);
+	if (!zx_spdif)
+		return -ENOMEM;
+
+	zx_spdif->dai_clk = devm_clk_get(&pdev->dev, "tx");
+	if (IS_ERR(zx_spdif->dai_clk)) {
+		dev_err(&pdev->dev, "Fail to get clk\n");
+		return PTR_ERR(zx_spdif->dai_clk);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	zx_spdif->mapbase = res->start;
+	zx_spdif->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	if (!zx_spdif->reg_base) {
+		dev_err(&pdev->dev, "ioremap failed!\n");
+		return -EIO;
+	}
+
+	zx_spdif_dev_init(zx_spdif->reg_base);
+	platform_set_drvdata(pdev, zx_spdif);
+
+	ret = devm_snd_soc_register_component(&pdev->dev, &zx_spdif_component,
+					 &zx_spdif_dai, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "Register DAI failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+	if (ret)
+		dev_err(&pdev->dev, "Register platform PCM failed: %d\n", ret);
+
+	return ret;
+}
+
+static const struct of_device_id zx_spdif_dt_ids[] = {
+	{ .compatible = "zte,zx296702-spdif", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, zx_spdif_dt_ids);
+
+static struct platform_driver spdif_driver = {
+	.probe = zx_spdif_probe,
+	.driver = {
+		.name = "zx-spdif",
+		.owner = THIS_MODULE,
+		.of_match_table = zx_spdif_dt_ids,
+	},
+};
+
+module_platform_driver(spdif_driver);
+
+MODULE_AUTHOR("Jun Nie <[e-mail]>");
+MODULE_DESCRIPTION("ZTE SPDIF SoC DAI");
+MODULE_LICENSE("GPL");