path: root/testing/linux-amlogic/0007-ASoC-meson-add-initial-spdif-dai-support.patch

From 67e2a1601f80648f5c318728218b788c51081fa3 Mon Sep 17 00:00:00 2001
From: Jerome Brunet <jbrunet@baylibre.com>
Date: Thu, 30 Mar 2017 13:46:03 +0200
Subject: [PATCH] ASoC: meson: add initial spdif dai support

Add support for the spdif dai found on Amlogic Meson SoC family.
With this initial implementation, only uncompressed pcm playback
from the spdif dma is supported. Future work will add compressed
support, pcm playback from i2s dma and capture.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

---
 sound/soc/meson/Kconfig     |   3 +-
 sound/soc/meson/Makefile    |   4 +-
 sound/soc/meson/spdif-dai.c | 374 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 379 insertions(+), 2 deletions(-)
 create mode 100644 sound/soc/meson/spdif-dai.c

diff --git a/sound/soc/meson/Kconfig b/sound/soc/meson/Kconfig
index 712303f..bc3d6f2 100644
--- a/sound/soc/meson/Kconfig
+++ b/sound/soc/meson/Kconfig
@@ -84,6 +84,7 @@ config SND_SOC_MESON_I2S
 config SND_SOC_MESON_SPDIF
 	tristate "Meson spdif interface"
 	depends on SND_SOC_MESON
+	select SND_PCM_IEC958
 	help
-	  Say Y or M if you want to add support for spdif dma driver for Amlogic
+	  Say Y or M if you want to add support for spdif driver for Amlogic
 	  Meson SoCs.
diff --git a/sound/soc/meson/Makefile b/sound/soc/meson/Makefile
index dc5164a7..44f79d8 100644
--- a/sound/soc/meson/Makefile
+++ b/sound/soc/meson/Makefile
@@ -24,8 +24,10 @@ snd-soc-meson-audio-core-objs	 := audio-core.o
 snd-soc-meson-aiu-i2s-dma-objs	 := aiu-i2s-dma.o
 snd-soc-meson-aiu-spdif-dma-objs := aiu-spdif-dma.o
 snd-soc-meson-i2s-dai-objs	 := i2s-dai.o
+snd-soc-meson-spdif-dai-objs	 := spdif-dai.o
 
 obj-$(CONFIG_SND_SOC_MESON) += snd-soc-meson-audio-core.o
 obj-$(CONFIG_SND_SOC_MESON_I2S)	+= snd-soc-meson-aiu-i2s-dma.o
 obj-$(CONFIG_SND_SOC_MESON_I2S)	+= snd-soc-meson-i2s-dai.o
-obj-$(CONFIG_SND_SOC_MESON_SPDIF) += snd-soc-meson-aiu-spdif-dma.o
\ No newline at end of file
+obj-$(CONFIG_SND_SOC_MESON_SPDIF) += snd-soc-meson-aiu-spdif-dma.o
+obj-$(CONFIG_SND_SOC_MESON_SPDIF) += snd-soc-meson-spdif-dai.o
\ No newline at end of file
diff --git a/sound/soc/meson/spdif-dai.c b/sound/soc/meson/spdif-dai.c
new file mode 100644
index 0000000..e763000
--- /dev/null
+++ b/sound/soc/meson/spdif-dai.c
@@ -0,0 +1,374 @@
+/*
+ * Copyright (C) 2017 BayLibre, SAS
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ * Copyright (C) 2017 Amlogic, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-dai.h>
+#include <sound/pcm_iec958.h>
+
+#include "aiu-regs.h"
+#include "audio-core.h"
+
+#define DRV_NAME "meson-spdif-dai"
+
+struct meson_spdif_dai {
+	struct meson_audio_core_data *core;
+	struct clk *iface;
+	struct clk *fast;
+	struct clk *mclk_i958;
+	struct clk *mclk;
+};
+
+#define AIU_CLK_CTRL_958_DIV_EN			BIT(1)
+#define AIU_CLK_CTRL_958_DIV_MASK		GENMASK(5, 4)
+#define AIU_CLK_CTRL_958_DIV_MORE		BIT(12)
+#define AIU_MEM_IEC958_CONTROL_MODE_LINEAR	BIT(8)
+#define AIU_958_CTRL_HOLD_EN			BIT(0)
+#define AIU_958_MISC_NON_PCM			BIT(0)
+#define AIU_958_MISC_MODE_16BITS		BIT(1)
+#define AIU_958_MISC_16BITS_ALIGN_MASK		GENMASK(6, 5)
+#define AIU_958_MISC_16BITS_ALIGN(val)		((val) << 5)
+#define AIU_958_MISC_MODE_32BITS		BIT(7)
+#define AIU_958_MISC_32BITS_SHIFT_MASK		GENMASK(10, 8)
+#define AIU_958_MISC_32BITS_SHIFT(val)		((val) << 8)
+#define AIU_958_MISC_U_FROM_STREAM		BIT(12)
+#define AIU_958_MISC_FORCE_LR			BIT(13)
+
+#define AIU_CS_WORD_LEN 4
+
+static void __hold(struct meson_spdif_dai *priv, bool enable)
+{
+	regmap_update_bits(priv->core->aiu, AIU_958_CTRL,
+			   AIU_958_CTRL_HOLD_EN,
+			   enable ? AIU_958_CTRL_HOLD_EN : 0);
+}
+
+static void __divider_enable(struct meson_spdif_dai *priv, bool enable)
+{
+	regmap_update_bits(priv->core->aiu, AIU_CLK_CTRL,
+			   AIU_CLK_CTRL_958_DIV_EN,
+			   enable ? AIU_CLK_CTRL_958_DIV_EN : 0);
+}
+
+static void __playback_start(struct meson_spdif_dai *priv)
+{
+	__divider_enable(priv, true);
+	__hold(priv, false);
+}
+
+static void __playback_stop(struct meson_spdif_dai *priv)
+{
+	__hold(priv, true);
+	__divider_enable(priv, false);
+}
+
+static int meson_spdif_dai_trigger(struct snd_pcm_substream *substream, int cmd,
+				   struct snd_soc_dai *dai)
+{
+	struct meson_spdif_dai *priv = snd_soc_dai_get_drvdata(dai);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		__playback_start(priv);
+		return 0;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		__playback_stop(priv);
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int __setup_spdif_clk(struct meson_spdif_dai *priv, unsigned int rate)
+{
+	unsigned int mrate;
+
+	/* Leave the internal divisor alone */
+	regmap_update_bits(priv->core->aiu, AIU_CLK_CTRL,
+			   AIU_CLK_CTRL_958_DIV_MASK |
+			   AIU_CLK_CTRL_958_DIV_MORE,
+			   0);
+
+	/* 2 * 32bits per subframe * 2 channels = 128 */
+	mrate = rate * 128;
+	return clk_set_rate(priv->mclk, mrate);
+}
+
+static int __setup_cs_word(struct meson_spdif_dai *priv,
+			   struct snd_pcm_hw_params *params)
+{
+	u8 cs[AIU_CS_WORD_LEN];
+	u32 val;
+	int ret;
+
+	ret = snd_pcm_create_iec958_consumer_hw_params(params, cs,
+						       AIU_CS_WORD_LEN);
+	if (ret < 0)
+		return -EINVAL;
+
+	/* Write the 1st half word */
+	val = cs[1] | cs[0] << 8;
+	regmap_write(priv->core->aiu, AIU_958_CHSTAT_L0, val);
+	regmap_write(priv->core->aiu, AIU_958_CHSTAT_R0, val);
+
+	/* Write the 2nd half word */
+	val = cs[3] | cs[2] << 8;
+	regmap_write(priv->core->aiu, AIU_958_CHSTAT_L1, val);
+	regmap_write(priv->core->aiu, AIU_958_CHSTAT_R1, val);
+
+	return 0;
+}
+
+static int __setup_pcm_fmt(struct meson_spdif_dai *priv,
+			   unsigned int width)
+{
+	u32 val = 0;
+
+	switch (width) {
+	case 16:
+		val |= AIU_958_MISC_MODE_16BITS;
+		val |= AIU_958_MISC_16BITS_ALIGN(2);
+		break;
+	case 32:
+	case 24:
+		/*
+		 * Looks like this should only be set for 32bits mode, but the
+		 * vendor kernel sets it like this for 24bits as well, let's
+		 * try and see
+		 */
+		val |= AIU_958_MISC_MODE_32BITS;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* No idea what this actually does, copying the vendor kernel for now */
+	val |= AIU_958_MISC_FORCE_LR;
+	val |= AIU_958_MISC_U_FROM_STREAM;
+
+	regmap_update_bits(priv->core->aiu, AIU_958_MISC,
+			   AIU_958_MISC_NON_PCM |
+			   AIU_958_MISC_MODE_16BITS |
+			   AIU_958_MISC_16BITS_ALIGN_MASK |
+			   AIU_958_MISC_MODE_32BITS |
+			   AIU_958_MISC_FORCE_LR,
+			   val);
+
+	return 0;
+}
+
+static int meson_spdif_dai_hw_params(struct snd_pcm_substream *substream,
+				     struct snd_pcm_hw_params *params,
+				     struct snd_soc_dai *dai)
+{
+	struct meson_spdif_dai *priv = snd_soc_dai_get_drvdata(dai);
+	int ret;
+
+	ret = __setup_spdif_clk(priv, params_rate(params));
+	if (ret) {
+		dev_err(dai->dev, "Unable to set the spdif clock\n");
+		return ret;
+	}
+
+	ret = __setup_cs_word(priv, params);
+	if (ret) {
+		dev_err(dai->dev, "Unable to set the channel status word\n");
+		return ret;
+	}
+
+	ret = __setup_pcm_fmt(priv, params_width(params));
+	if (ret) {
+		dev_err(dai->dev, "Unable to set the pcm format\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int meson_spdif_dai_startup(struct snd_pcm_substream *substream,
+				   struct snd_soc_dai *dai)
+{
+	struct meson_spdif_dai *priv = snd_soc_dai_get_drvdata(dai);
+	int ret;
+
+	/* Power up the spdif fast domain - can't write the registers w/o it */
+	ret = clk_prepare_enable(priv->fast);
+	if (ret)
+		goto out_clk_fast;
+
+	/* Make sure nothing gets out of the DAI yet*/
+	__hold(priv, true);
+
+	ret = clk_set_parent(priv->mclk, priv->mclk_i958);
+	if (ret)
+		return ret;
+
+	/* Enable the clock gate */
+	ret = clk_prepare_enable(priv->iface);
+	if (ret)
+		goto out_clk_iface;
+
+	/* Enable the spdif clock */
+	ret = clk_prepare_enable(priv->mclk);
+	if (ret)
+		goto out_mclk;
+
+	/*
+	 * Make sure the interface expect a memory layout we can work with
+	 * MEM prefixed register usually belong to the DMA, but when the spdif
+	 * DAI takes data from the i2s buffer, we need to make sure it works in
+	 * split mode and not the  "normal mode" (channel samples packed in
+	 * 32 bytes groups)
+	 */
+	regmap_update_bits(priv->core->aiu, AIU_MEM_IEC958_CONTROL,
+			   AIU_MEM_IEC958_CONTROL_MODE_LINEAR,
+			   AIU_MEM_IEC958_CONTROL_MODE_LINEAR);
+
+	return 0;
+
+out_mclk:
+	clk_disable_unprepare(priv->iface);
+out_clk_iface:
+	clk_disable_unprepare(priv->fast);
+out_clk_fast:
+	return ret;
+}
+
+static void meson_spdif_dai_shutdown(struct snd_pcm_substream *substream,
+				   struct snd_soc_dai *dai)
+{
+	struct meson_spdif_dai *priv = snd_soc_dai_get_drvdata(dai);
+
+	clk_disable_unprepare(priv->iface);
+	clk_disable_unprepare(priv->mclk);
+	clk_disable_unprepare(priv->fast);
+}
+
+static const struct snd_soc_dai_ops meson_spdif_dai_ops = {
+	.startup    = meson_spdif_dai_startup,
+	.shutdown   = meson_spdif_dai_shutdown,
+	.trigger    = meson_spdif_dai_trigger,
+	.hw_params  = meson_spdif_dai_hw_params,
+};
+
+static struct snd_soc_dai_driver meson_spdif_dai = {
+	.playback = {
+		.stream_name = "Playback",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = (SNDRV_PCM_RATE_32000 |
+			  SNDRV_PCM_RATE_44100 |
+			  SNDRV_PCM_RATE_48000 |
+			  SNDRV_PCM_RATE_96000 |
+			  SNDRV_PCM_RATE_192000),
+		.formats = (SNDRV_PCM_FMTBIT_S16_LE |
+			    SNDRV_PCM_FMTBIT_S24_LE)
+	},
+	.ops = &meson_spdif_dai_ops,
+};
+
+static const struct snd_soc_component_driver meson_spdif_dai_component = {
+	.name	= DRV_NAME,
+};
+
+static int meson_spdif_dai_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct meson_spdif_dai *priv;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, priv);
+	priv->core = dev_get_drvdata(dev->parent);
+
+	priv->fast = devm_clk_get(dev, "fast");
+	if (IS_ERR(priv->fast)) {
+		if (PTR_ERR(priv->fast) != -EPROBE_DEFER)
+			dev_err(dev, "Can't get spdif fast domain clockt\n");
+		return PTR_ERR(priv->fast);
+	}
+
+	priv->iface = devm_clk_get(dev, "iface");
+	if (IS_ERR(priv->iface)) {
+		if (PTR_ERR(priv->iface) != -EPROBE_DEFER)
+			dev_err(dev,
+				"Can't get the dai clock gate\n");
+		return PTR_ERR(priv->iface);
+	}
+
+	priv->mclk_i958 = devm_clk_get(dev, "mclk_i958");
+	if (IS_ERR(priv->mclk_i958)) {
+		if (PTR_ERR(priv->mclk_i958) != -EPROBE_DEFER)
+			dev_err(dev, "Can't get the spdif master clock\n");
+		return PTR_ERR(priv->mclk_i958);
+	}
+
+	/*
+	 * TODO: the spdif dai can also get its data from the i2s fifo.
+	 * For this use-case, the DAI driver will need to get the i2s master
+	 * clock in order to reparent the spdif clock from cts_mclk_i958 to
+	 * cts_amclk
+	 */
+
+	priv->mclk = devm_clk_get(dev, "mclk");
+	if (IS_ERR(priv->mclk)) {
+		if (PTR_ERR(priv->mclk) != -EPROBE_DEFER)
+			dev_err(dev, "Can't get the spdif input mux clock\n");
+		return PTR_ERR(priv->mclk);
+	}
+
+	return devm_snd_soc_register_component(dev, &meson_spdif_dai_component,
+					       &meson_spdif_dai, 1);
+}
+
+static const struct of_device_id meson_spdif_dai_of_match[] = {
+	{ .compatible = "amlogic,meson-spdif-dai", },
+	{ .compatible = "amlogic,meson-gxbb-spdif-dai", },
+	{ .compatible = "amlogic,meson-gxl-spdif-dai", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, meson_spdif_dai_of_match);
+
+static struct platform_driver meson_spdif_dai_pdrv = {
+	.probe = meson_spdif_dai_probe,
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = meson_spdif_dai_of_match,
+	},
+};
+module_platform_driver(meson_spdif_dai_pdrv);
+
+MODULE_DESCRIPTION("Meson spdif DAI ASoC Driver");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL v2");