[PATCH 0/3] add Xilinx SPDIF audio driver

[PATCH 0/3] add Xilinx SPDIF audio driver

[Maruthi Srinivas Bayyavarapu]

SPDIF IP supports playback and capture of audio in AES format. Each IP
instance can only work in either transmit or receive mode exclusively.
The patchset adds support for playback and capture functionality.

Maruthi Srinivas Bayyavarapu (3):
  dt-bindings: ASoC: xlnx,spdif: Document spdif bindings
  ASoC: xlnx: add SPDIF audio driver
  ASoC: xlnx: enable SPDIF driver build

 .../devicetree/bindings/sound/xlnx,spdif.txt       |  28 ++
 sound/soc/xilinx/Kconfig                           |   7 +
 sound/soc/xilinx/Makefile                          |   2 +
 sound/soc/xilinx/xlnx_spdif.c                      | 339 +++++++++++++++++++++
 4 files changed, 376 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/xlnx,spdif.txt
 create mode 100644 sound/soc/xilinx/xlnx_spdif.c

-- 
2.7.4

[PATCH 1/3] dt-bindings: ASoC: xlnx,spdif: Document spdif bindings

[Maruthi Srinivas Bayyavarapu]

Added documentation for SPDIF IP DT bindings.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
---
 .../devicetree/bindings/sound/xlnx,spdif.txt       | 28 ++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/xlnx,spdif.txt

diff --git a/Documentation/devicetree/bindings/sound/xlnx,spdif.txt b/Documentation/devicetree/bindings/sound/xlnx,spdif.txt
new file mode 100644
index 0000000..15c2d64
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/xlnx,spdif.txt
@@ -0,0 +1,28 @@
+Device-Tree bindings for Xilinx SPDIF IP
+
+The IP supports playback and capture of SPDIF audio
+
+Required properties:
+ - compatible: "xlnx,spdif-2.0"
+ - clock-names: List of input clocks.
+   Required elements: "s_axi_aclk", "aud_clk_i"
+ - clocks: Input clock specifier. Refer to common clock bindings.
+ - reg: Base address and address length of the IP core instance.
+ - interrupts-parent: Phandle for interrupt controller.
+ - interrupts: List of Interrupt numbers.
+ - xlnx,spdif-mode: 0 :- receiver mode
+		    1 :- transmitter mode
+ - xlnx,aud_clk_i: input audio clock value.
+
+Example:
+	spdif_0: spdif@80010000 {
+		clock-names = "aud_clk_i", "s_axi_aclk";
+		clocks = <&misc_clk_0>, <&clk 71>;
+		compatible = "xlnx,spdif-2.0";
+		interrupt-names = "spdif_interrupt";
+		interrupt-parent = <&gic>;
+		interrupts = <0 91 4>;
+		reg = <0x0 0x80010000 0x0 0x10000>;
+		xlnx,spdif-mode = <1>;
+		xlnx,aud_clk_i = <49152913>;
+	};
-- 
2.7.4

[PATCH 2/3] ASoC: xlnx: add SPDIF audio driver

[Maruthi Srinivas Bayyavarapu]

Added SPDIF audio driver. This provides playback and capture of
AES audio over SPDIF interface.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
---
 sound/soc/xilinx/xlnx_spdif.c | 339 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 339 insertions(+)
 create mode 100644 sound/soc/xilinx/xlnx_spdif.c

diff --git a/sound/soc/xilinx/xlnx_spdif.c b/sound/soc/xilinx/xlnx_spdif.c
new file mode 100644
index 0000000..3b9000f
--- /dev/null
+++ b/sound/soc/xilinx/xlnx_spdif.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Xilinx ASoC SPDIF audio support
+//
+// Copyright (C) 2018 Xilinx, Inc.
+//
+// Author: Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>
+//
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define XLNX_SPDIF_RATES \
+	(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 XLNX_SPDIF_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+#define XSPDIF_IRQ_STS_REG		0x20
+#define XSPDIF_IRQ_ENABLE_REG		0x28
+#define XSPDIF_SOFT_RESET_REG		0x40
+#define XSPDIF_CONTROL_REG		0x44
+#define XSPDIF_CHAN_0_STS_REG		0x4C
+#define XSPDIF_GLOBAL_IRQ_ENABLE_REG	0x1C
+#define XSPDIF_CH_A_USER_DATA_REG_0	0x64
+
+#define XSPDIF_CORE_ENABLE_MASK		BIT(0)
+#define XSPDIF_FIFO_FLUSH_MASK		BIT(1)
+#define XSPDIF_CH_STS_MASK		BIT(5)
+#define XSPDIF_GLOBAL_IRQ_ENABLE	BIT(31)
+#define XSPDIF_CLOCK_CONFIG_BITS_MASK	GENMASK(5, 2)
+#define XSPDIF_CLOCK_CONFIG_BITS_SHIFT	2
+#define XSPDIF_SOFT_RESET_VALUE		0xA
+
+#define MAX_CHANNELS			2
+#define AES_SAMPLE_WIDTH		32
+#define CH_STATUS_UPDATE_TIMEOUT	40
+
+struct spdif_dev_data {
+	u32 mode;
+	u32 aclk;
+	bool rx_chsts_updated;
+	void __iomem *base;
+	struct clk *axi_clk;
+	wait_queue_head_t chsts_q;
+};
+
+static irqreturn_t xlnx_spdifrx_irq_handler(int irq, void *arg)
+{
+	u32 val;
+	struct spdif_dev_data *ctx = arg;
+
+	val = readl(ctx->base + XSPDIF_IRQ_STS_REG);
+	if (val & XSPDIF_CH_STS_MASK) {
+		writel(val & XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_STS_REG);
+		val = readl(ctx->base +
+			    XSPDIF_IRQ_ENABLE_REG);
+		writel(val & ~XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_ENABLE_REG);
+
+		ctx->rx_chsts_updated = true;
+		wake_up_interruptible(&ctx->chsts_q);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static int xlnx_spdif_startup(struct snd_pcm_substream *substream,
+			      struct snd_soc_dai *dai)
+{
+	u32 val;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	val |= XSPDIF_FIFO_FLUSH_MASK;
+	writel(val, ctx->base + XSPDIF_CONTROL_REG);
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		writel(XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_ENABLE_REG);
+		writel(XSPDIF_GLOBAL_IRQ_ENABLE,
+		       ctx->base + XSPDIF_GLOBAL_IRQ_ENABLE_REG);
+	}
+
+	return 0;
+}
+
+static void xlnx_spdif_shutdown(struct snd_pcm_substream *substream,
+				struct snd_soc_dai *dai)
+{
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
+}
+
+static int xlnx_spdif_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params,
+				struct snd_soc_dai *dai)
+{
+	u32 val, clk_div, clk_cfg;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	clk_div = DIV_ROUND_CLOSEST(ctx->aclk, MAX_CHANNELS * AES_SAMPLE_WIDTH *
+				    params_rate(params));
+
+	switch (clk_div) {
+	case 4:
+		clk_cfg = 0;
+		break;
+	case 8:
+		clk_cfg = 1;
+		break;
+	case 16:
+		clk_cfg = 2;
+		break;
+	case 24:
+		clk_cfg = 3;
+		break;
+	case 32:
+		clk_cfg = 4;
+		break;
+	case 48:
+		clk_cfg = 5;
+		break;
+	case 64:
+		clk_cfg = 6;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	val &= ~XSPDIF_CLOCK_CONFIG_BITS_MASK;
+	val |= clk_cfg << XSPDIF_CLOCK_CONFIG_BITS_SHIFT;
+	writel(val, ctx->base + XSPDIF_CONTROL_REG);
+
+	return 0;
+}
+
+static int rx_stream_detect(struct snd_soc_dai *dai)
+{
+	int err;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+	unsigned long jiffies = msecs_to_jiffies(CH_STATUS_UPDATE_TIMEOUT);
+
+	/* start capture only if stream is detected within 40ms timeout */
+	err = wait_event_interruptible_timeout(ctx->chsts_q,
+					       ctx->rx_chsts_updated,
+					       jiffies);
+	if (!err) {
+		dev_err(dai->dev, "No streaming audio detected!\n");
+		return -EINVAL;
+	}
+	ctx->rx_chsts_updated = false;
+
+	return 0;
+}
+
+static int xlnx_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+			      struct snd_soc_dai *dai)
+{
+	u32 val;
+	int ret = 0;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		val |= XSPDIF_CORE_ENABLE_MASK;
+		writel(val, ctx->base + XSPDIF_CONTROL_REG);
+		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+			ret = rx_stream_detect(dai);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		val &= ~XSPDIF_CORE_ENABLE_MASK;
+		writel(val, ctx->base + XSPDIF_CONTROL_REG);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct snd_soc_dai_ops xlnx_spdif_dai_ops = {
+	.startup = xlnx_spdif_startup,
+	.shutdown = xlnx_spdif_shutdown,
+	.trigger = xlnx_spdif_trigger,
+	.hw_params = xlnx_spdif_hw_params,
+};
+
+static struct snd_soc_dai_driver xlnx_spdif_tx_dai = {
+	.name = "xlnx_spdif_tx",
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = XLNX_SPDIF_RATES,
+		.formats = XLNX_SPDIF_FORMATS,
+	},
+	.ops = &xlnx_spdif_dai_ops,
+};
+
+static struct snd_soc_dai_driver xlnx_spdif_rx_dai = {
+	.name = "xlnx_spdif_rx",
+	.capture = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = XLNX_SPDIF_RATES,
+		.formats = XLNX_SPDIF_FORMATS,
+	},
+	.ops = &xlnx_spdif_dai_ops,
+};
+
+static const struct snd_soc_component_driver xlnx_spdif_component = {
+	.name = "xlnx-spdif",
+};
+
+static const struct of_device_id xlnx_spdif_of_match[] = {
+	{ .compatible = "xlnx,spdif-2.0", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xlnx_spdif_of_match);
+
+static int xlnx_spdif_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *res;
+	struct snd_soc_dai_driver *dai_drv;
+	struct spdif_dev_data *ctx;
+
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->axi_clk = devm_clk_get(dev, "s_axi_aclk");
+	if (IS_ERR(ctx->axi_clk)) {
+		ret = PTR_ERR(ctx->axi_clk);
+		dev_err(dev, "failed to get s_axi_aclk(%d)\n", ret);
+		return ret;
+	}
+	ret = clk_prepare_enable(ctx->axi_clk);
+	if (ret) {
+		dev_err(dev, "failed to enable s_axi_aclk(%d)\n", ret);
+		return ret;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ctx->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ctx->base)) {
+		ret = PTR_ERR(ctx->base);
+		goto clk_err;
+	}
+	ret = of_property_read_u32(node, "xlnx,spdif-mode", &ctx->mode);
+	if (ret < 0) {
+		dev_err(dev, "cannot get SPDIF mode\n");
+		goto clk_err;
+	}
+	if (ctx->mode) {
+		dai_drv = &xlnx_spdif_tx_dai;
+	} else {
+		res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+		if (!res) {
+			dev_err(dev, "No IRQ resource found\n");
+			ret = -ENODEV;
+			goto clk_err;
+		}
+		ret = devm_request_irq(dev, res->start,
+				       xlnx_spdifrx_irq_handler,
+				       0, "XLNX_SPDIF_RX", ctx);
+		if (ret) {
+			dev_err(dev, "spdif rx irq request failed\n");
+			ret = -ENODEV;
+			goto clk_err;
+		}
+
+		init_waitqueue_head(&ctx->chsts_q);
+		dai_drv = &xlnx_spdif_rx_dai;
+	}
+
+	ret = of_property_read_u32(node, "xlnx,aud_clk_i", &ctx->aclk);
+	if (ret < 0) {
+		dev_err(dev, "cannot get aud_clk_i value\n");
+		goto clk_err;
+	}
+
+	dev_set_drvdata(dev, ctx);
+
+	ret = devm_snd_soc_register_component(dev, &xlnx_spdif_component,
+					      dai_drv, 1);
+	if (ret) {
+		dev_err(dev, "SPDIF component registration failed\n");
+		goto clk_err;
+	}
+
+	writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
+	dev_info(dev, "%s DAI registered\n", dai_drv->name);
+
+clk_err:
+	clk_disable_unprepare(ctx->axi_clk);
+	return ret;
+}
+
+static int xlnx_spdif_remove(struct platform_device *pdev)
+{
+	struct spdif_dev_data *ctx = dev_get_drvdata(&pdev->dev);
+
+	clk_disable_unprepare(ctx->axi_clk);
+	return 0;
+}
+
+static struct platform_driver xlnx_spdif_driver = {
+	.driver = {
+		.name = "xlnx-spdif",
+		.of_match_table = xlnx_spdif_of_match,
+	},
+	.probe = xlnx_spdif_probe,
+	.remove = xlnx_spdif_remove,
+};
+module_platform_driver(xlnx_spdif_driver);
+
+MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");
+MODULE_DESCRIPTION("XILINX SPDIF driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

[PATCH 3/3] ASoC: xlnx: enable SPDIF driver build

[Maruthi Srinivas Bayyavarapu]

Added SPDIF driver build related changes.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
---
 sound/soc/xilinx/Kconfig  | 7 +++++++
 sound/soc/xilinx/Makefile | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/sound/soc/xilinx/Kconfig b/sound/soc/xilinx/Kconfig
index ac48d6a..47f606b9 100644
--- a/sound/soc/xilinx/Kconfig
+++ b/sound/soc/xilinx/Kconfig
@@ -13,3 +13,10 @@ config SND_SOC_XILINX_AUDIO_FORMATTER
           Select this option to enable Xilinx audio formatter
           support. This provides DMA platform device support for
           audio functionality.
+
+config SND_SOC_XILINX_SPDIF
+        tristate "Audio support for the the Xilinx SPDIF"
+        help
+          Select this option to enable Xilinx SPDIF Audio.
+          This provides playback and capture of SPDIF audio in
+          AES format.
diff --git a/sound/soc/xilinx/Makefile b/sound/soc/xilinx/Makefile
index 432693b..d79fd38 100644
--- a/sound/soc/xilinx/Makefile
+++ b/sound/soc/xilinx/Makefile
@@ -2,3 +2,5 @@ snd-soc-xlnx-i2s-objs      := xlnx_i2s.o
 obj-$(CONFIG_SND_SOC_XILINX_I2S) += snd-soc-xlnx-i2s.o
 snd-soc-xlnx-formatter-pcm-objs := xlnx_formatter_pcm.o
 obj-$(CONFIG_SND_SOC_XILINX_AUDIO_FORMATTER) += snd-soc-xlnx-formatter-pcm.o
+snd-soc-xlnx-spdif-objs := xlnx_spdif.o
+obj-$(CONFIG_SND_SOC_XILINX_SPDIF) += snd-soc-xlnx-spdif.o
-- 
2.7.4

Applied "ASoC: xlnx: enable SPDIF driver build" to the asoc tree

[Mark Brown]

The patch

   ASoC: xlnx: enable SPDIF driver build

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

From 47caf048a017ecc95cdd0802bc3b015a1559e601 Mon Sep 17 00:00:00 2001
From: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Date: Thu, 3 Jan 2019 23:39:53 +0530
Subject: [PATCH] ASoC: xlnx: enable SPDIF driver build

Added SPDIF driver build related changes.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/xilinx/Kconfig  | 7 +++++++
 sound/soc/xilinx/Makefile | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/sound/soc/xilinx/Kconfig b/sound/soc/xilinx/Kconfig
index ac48d6a00c36..47f606b924e4 100644
--- a/sound/soc/xilinx/Kconfig
+++ b/sound/soc/xilinx/Kconfig
@@ -13,3 +13,10 @@ config SND_SOC_XILINX_AUDIO_FORMATTER
           Select this option to enable Xilinx audio formatter
           support. This provides DMA platform device support for
           audio functionality.
+
+config SND_SOC_XILINX_SPDIF
+        tristate "Audio support for the the Xilinx SPDIF"
+        help
+          Select this option to enable Xilinx SPDIF Audio.
+          This provides playback and capture of SPDIF audio in
+          AES format.
diff --git a/sound/soc/xilinx/Makefile b/sound/soc/xilinx/Makefile
index 432693b1cc79..d79fd38b094b 100644
--- a/sound/soc/xilinx/Makefile
+++ b/sound/soc/xilinx/Makefile
@@ -2,3 +2,5 @@ snd-soc-xlnx-i2s-objs      := xlnx_i2s.o
 obj-$(CONFIG_SND_SOC_XILINX_I2S) += snd-soc-xlnx-i2s.o
 snd-soc-xlnx-formatter-pcm-objs := xlnx_formatter_pcm.o
 obj-$(CONFIG_SND_SOC_XILINX_AUDIO_FORMATTER) += snd-soc-xlnx-formatter-pcm.o
+snd-soc-xlnx-spdif-objs := xlnx_spdif.o
+obj-$(CONFIG_SND_SOC_XILINX_SPDIF) += snd-soc-xlnx-spdif.o
-- 
2.20.1

Applied "ASoC: xlnx: add SPDIF audio driver" to the asoc tree

[Mark Brown]

The patch

   ASoC: xlnx: add SPDIF audio driver

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

From b1d2a4cca20cb84ffe02116fd8d2b91a94d49d5e Mon Sep 17 00:00:00 2001
From: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Date: Thu, 3 Jan 2019 23:39:52 +0530
Subject: [PATCH] ASoC: xlnx: add SPDIF audio driver

Added SPDIF audio driver. This provides playback and capture of
AES audio over SPDIF interface.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/xilinx/xlnx_spdif.c | 339 ++++++++++++++++++++++++++++++++++
 1 file changed, 339 insertions(+)
 create mode 100644 sound/soc/xilinx/xlnx_spdif.c

diff --git a/sound/soc/xilinx/xlnx_spdif.c b/sound/soc/xilinx/xlnx_spdif.c
new file mode 100644
index 000000000000..3b9000fd8c49
--- /dev/null
+++ b/sound/soc/xilinx/xlnx_spdif.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Xilinx ASoC SPDIF audio support
+//
+// Copyright (C) 2018 Xilinx, Inc.
+//
+// Author: Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>
+//
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define XLNX_SPDIF_RATES \
+	(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 XLNX_SPDIF_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+#define XSPDIF_IRQ_STS_REG		0x20
+#define XSPDIF_IRQ_ENABLE_REG		0x28
+#define XSPDIF_SOFT_RESET_REG		0x40
+#define XSPDIF_CONTROL_REG		0x44
+#define XSPDIF_CHAN_0_STS_REG		0x4C
+#define XSPDIF_GLOBAL_IRQ_ENABLE_REG	0x1C
+#define XSPDIF_CH_A_USER_DATA_REG_0	0x64
+
+#define XSPDIF_CORE_ENABLE_MASK		BIT(0)
+#define XSPDIF_FIFO_FLUSH_MASK		BIT(1)
+#define XSPDIF_CH_STS_MASK		BIT(5)
+#define XSPDIF_GLOBAL_IRQ_ENABLE	BIT(31)
+#define XSPDIF_CLOCK_CONFIG_BITS_MASK	GENMASK(5, 2)
+#define XSPDIF_CLOCK_CONFIG_BITS_SHIFT	2
+#define XSPDIF_SOFT_RESET_VALUE		0xA
+
+#define MAX_CHANNELS			2
+#define AES_SAMPLE_WIDTH		32
+#define CH_STATUS_UPDATE_TIMEOUT	40
+
+struct spdif_dev_data {
+	u32 mode;
+	u32 aclk;
+	bool rx_chsts_updated;
+	void __iomem *base;
+	struct clk *axi_clk;
+	wait_queue_head_t chsts_q;
+};
+
+static irqreturn_t xlnx_spdifrx_irq_handler(int irq, void *arg)
+{
+	u32 val;
+	struct spdif_dev_data *ctx = arg;
+
+	val = readl(ctx->base + XSPDIF_IRQ_STS_REG);
+	if (val & XSPDIF_CH_STS_MASK) {
+		writel(val & XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_STS_REG);
+		val = readl(ctx->base +
+			    XSPDIF_IRQ_ENABLE_REG);
+		writel(val & ~XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_ENABLE_REG);
+
+		ctx->rx_chsts_updated = true;
+		wake_up_interruptible(&ctx->chsts_q);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static int xlnx_spdif_startup(struct snd_pcm_substream *substream,
+			      struct snd_soc_dai *dai)
+{
+	u32 val;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	val |= XSPDIF_FIFO_FLUSH_MASK;
+	writel(val, ctx->base + XSPDIF_CONTROL_REG);
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+		writel(XSPDIF_CH_STS_MASK,
+		       ctx->base + XSPDIF_IRQ_ENABLE_REG);
+		writel(XSPDIF_GLOBAL_IRQ_ENABLE,
+		       ctx->base + XSPDIF_GLOBAL_IRQ_ENABLE_REG);
+	}
+
+	return 0;
+}
+
+static void xlnx_spdif_shutdown(struct snd_pcm_substream *substream,
+				struct snd_soc_dai *dai)
+{
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
+}
+
+static int xlnx_spdif_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params,
+				struct snd_soc_dai *dai)
+{
+	u32 val, clk_div, clk_cfg;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	clk_div = DIV_ROUND_CLOSEST(ctx->aclk, MAX_CHANNELS * AES_SAMPLE_WIDTH *
+				    params_rate(params));
+
+	switch (clk_div) {
+	case 4:
+		clk_cfg = 0;
+		break;
+	case 8:
+		clk_cfg = 1;
+		break;
+	case 16:
+		clk_cfg = 2;
+		break;
+	case 24:
+		clk_cfg = 3;
+		break;
+	case 32:
+		clk_cfg = 4;
+		break;
+	case 48:
+		clk_cfg = 5;
+		break;
+	case 64:
+		clk_cfg = 6;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	val &= ~XSPDIF_CLOCK_CONFIG_BITS_MASK;
+	val |= clk_cfg << XSPDIF_CLOCK_CONFIG_BITS_SHIFT;
+	writel(val, ctx->base + XSPDIF_CONTROL_REG);
+
+	return 0;
+}
+
+static int rx_stream_detect(struct snd_soc_dai *dai)
+{
+	int err;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+	unsigned long jiffies = msecs_to_jiffies(CH_STATUS_UPDATE_TIMEOUT);
+
+	/* start capture only if stream is detected within 40ms timeout */
+	err = wait_event_interruptible_timeout(ctx->chsts_q,
+					       ctx->rx_chsts_updated,
+					       jiffies);
+	if (!err) {
+		dev_err(dai->dev, "No streaming audio detected!\n");
+		return -EINVAL;
+	}
+	ctx->rx_chsts_updated = false;
+
+	return 0;
+}
+
+static int xlnx_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+			      struct snd_soc_dai *dai)
+{
+	u32 val;
+	int ret = 0;
+	struct spdif_dev_data *ctx = dev_get_drvdata(dai->dev);
+
+	val = readl(ctx->base + XSPDIF_CONTROL_REG);
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		val |= XSPDIF_CORE_ENABLE_MASK;
+		writel(val, ctx->base + XSPDIF_CONTROL_REG);
+		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+			ret = rx_stream_detect(dai);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		val &= ~XSPDIF_CORE_ENABLE_MASK;
+		writel(val, ctx->base + XSPDIF_CONTROL_REG);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct snd_soc_dai_ops xlnx_spdif_dai_ops = {
+	.startup = xlnx_spdif_startup,
+	.shutdown = xlnx_spdif_shutdown,
+	.trigger = xlnx_spdif_trigger,
+	.hw_params = xlnx_spdif_hw_params,
+};
+
+static struct snd_soc_dai_driver xlnx_spdif_tx_dai = {
+	.name = "xlnx_spdif_tx",
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = XLNX_SPDIF_RATES,
+		.formats = XLNX_SPDIF_FORMATS,
+	},
+	.ops = &xlnx_spdif_dai_ops,
+};
+
+static struct snd_soc_dai_driver xlnx_spdif_rx_dai = {
+	.name = "xlnx_spdif_rx",
+	.capture = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = XLNX_SPDIF_RATES,
+		.formats = XLNX_SPDIF_FORMATS,
+	},
+	.ops = &xlnx_spdif_dai_ops,
+};
+
+static const struct snd_soc_component_driver xlnx_spdif_component = {
+	.name = "xlnx-spdif",
+};
+
+static const struct of_device_id xlnx_spdif_of_match[] = {
+	{ .compatible = "xlnx,spdif-2.0", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xlnx_spdif_of_match);
+
+static int xlnx_spdif_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *res;
+	struct snd_soc_dai_driver *dai_drv;
+	struct spdif_dev_data *ctx;
+
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	ctx->axi_clk = devm_clk_get(dev, "s_axi_aclk");
+	if (IS_ERR(ctx->axi_clk)) {
+		ret = PTR_ERR(ctx->axi_clk);
+		dev_err(dev, "failed to get s_axi_aclk(%d)\n", ret);
+		return ret;
+	}
+	ret = clk_prepare_enable(ctx->axi_clk);
+	if (ret) {
+		dev_err(dev, "failed to enable s_axi_aclk(%d)\n", ret);
+		return ret;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ctx->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ctx->base)) {
+		ret = PTR_ERR(ctx->base);
+		goto clk_err;
+	}
+	ret = of_property_read_u32(node, "xlnx,spdif-mode", &ctx->mode);
+	if (ret < 0) {
+		dev_err(dev, "cannot get SPDIF mode\n");
+		goto clk_err;
+	}
+	if (ctx->mode) {
+		dai_drv = &xlnx_spdif_tx_dai;
+	} else {
+		res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+		if (!res) {
+			dev_err(dev, "No IRQ resource found\n");
+			ret = -ENODEV;
+			goto clk_err;
+		}
+		ret = devm_request_irq(dev, res->start,
+				       xlnx_spdifrx_irq_handler,
+				       0, "XLNX_SPDIF_RX", ctx);
+		if (ret) {
+			dev_err(dev, "spdif rx irq request failed\n");
+			ret = -ENODEV;
+			goto clk_err;
+		}
+
+		init_waitqueue_head(&ctx->chsts_q);
+		dai_drv = &xlnx_spdif_rx_dai;
+	}
+
+	ret = of_property_read_u32(node, "xlnx,aud_clk_i", &ctx->aclk);
+	if (ret < 0) {
+		dev_err(dev, "cannot get aud_clk_i value\n");
+		goto clk_err;
+	}
+
+	dev_set_drvdata(dev, ctx);
+
+	ret = devm_snd_soc_register_component(dev, &xlnx_spdif_component,
+					      dai_drv, 1);
+	if (ret) {
+		dev_err(dev, "SPDIF component registration failed\n");
+		goto clk_err;
+	}
+
+	writel(XSPDIF_SOFT_RESET_VALUE, ctx->base + XSPDIF_SOFT_RESET_REG);
+	dev_info(dev, "%s DAI registered\n", dai_drv->name);
+
+clk_err:
+	clk_disable_unprepare(ctx->axi_clk);
+	return ret;
+}
+
+static int xlnx_spdif_remove(struct platform_device *pdev)
+{
+	struct spdif_dev_data *ctx = dev_get_drvdata(&pdev->dev);
+
+	clk_disable_unprepare(ctx->axi_clk);
+	return 0;
+}
+
+static struct platform_driver xlnx_spdif_driver = {
+	.driver = {
+		.name = "xlnx-spdif",
+		.of_match_table = xlnx_spdif_of_match,
+	},
+	.probe = xlnx_spdif_probe,
+	.remove = xlnx_spdif_remove,
+};
+module_platform_driver(xlnx_spdif_driver);
+
+MODULE_AUTHOR("Maruthi Srinivas Bayyavarapu <maruthis@xilinx.com>");
+MODULE_DESCRIPTION("XILINX SPDIF driver");
+MODULE_LICENSE("GPL v2");
-- 
2.20.1

Applied "dt-bindings: ASoC: xlnx, spdif: Document spdif bindings" to the asoc tree

[Mark Brown]

The patch

   dt-bindings: ASoC: xlnx, spdif: Document spdif bindings

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

From 2f00f7715e624d04e25d9cb8bb0f53884d3bcb59 Mon Sep 17 00:00:00 2001
From: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Date: Thu, 3 Jan 2019 23:39:51 +0530
Subject: [PATCH] dt-bindings: ASoC: xlnx, spdif: Document spdif bindings

Added documentation for SPDIF IP DT bindings.

Signed-off-by: Maruthi Srinivas Bayyavarapu <maruthi.srinivas.bayyavarapu@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 .../devicetree/bindings/sound/xlnx,spdif.txt  | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/xlnx,spdif.txt

diff --git a/Documentation/devicetree/bindings/sound/xlnx,spdif.txt b/Documentation/devicetree/bindings/sound/xlnx,spdif.txt
new file mode 100644
index 000000000000..15c2d64d247c
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/xlnx,spdif.txt
@@ -0,0 +1,28 @@
+Device-Tree bindings for Xilinx SPDIF IP
+
+The IP supports playback and capture of SPDIF audio
+
+Required properties:
+ - compatible: "xlnx,spdif-2.0"
+ - clock-names: List of input clocks.
+   Required elements: "s_axi_aclk", "aud_clk_i"
+ - clocks: Input clock specifier. Refer to common clock bindings.
+ - reg: Base address and address length of the IP core instance.
+ - interrupts-parent: Phandle for interrupt controller.
+ - interrupts: List of Interrupt numbers.
+ - xlnx,spdif-mode: 0 :- receiver mode
+		    1 :- transmitter mode
+ - xlnx,aud_clk_i: input audio clock value.
+
+Example:
+	spdif_0: spdif@80010000 {
+		clock-names = "aud_clk_i", "s_axi_aclk";
+		clocks = <&misc_clk_0>, <&clk 71>;
+		compatible = "xlnx,spdif-2.0";
+		interrupt-names = "spdif_interrupt";
+		interrupt-parent = <&gic>;
+		interrupts = <0 91 4>;
+		reg = <0x0 0x80010000 0x0 0x10000>;
+		xlnx,spdif-mode = <1>;
+		xlnx,aud_clk_i = <49152913>;
+	};
-- 
2.20.1