ASoC: fsl_aud2htx: Add aud2htx module driver

The AUD2HTX is a digital module that provides a bridge between
the Audio Subsystem and the HDMI RTX Subsystem. This module
includes intermediate storage to queue SDMA transactions prior
to being synchronized and passed to the HDMI RTX Subsystem over
the Audio Link.

The AUD2HTX contains a DMA request routed to the SDMA module.
This DMA request is controlled based on the watermark level in
the 32-entry sample buffer.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/1604281947-26874-2-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 311 insertions, 0 deletions

diff --git a/sound/soc/fsl/fsl_aud2htx.c b/sound/soc/fsl/fsl_aud2htx.c
new file mode 100644
index 000000000000..124aeb70f24e
--- /dev/null
+++ b/sound/soc/fsl/fsl_aud2htx.c
@@ -0,0 +1,311 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2020 NXP
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/pm_qos.h>
+#include <sound/core.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/pcm_params.h>
+#include <linux/dma-mapping.h>
+
+#include "fsl_aud2htx.h"
+#include "imx-pcm.h"
+
+static int fsl_aud2htx_trigger(struct snd_pcm_substream *substream, int cmd,
+			       struct snd_soc_dai *dai)
+{
+	struct fsl_aud2htx *aud2htx = snd_soc_dai_get_drvdata(dai);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL,
+				   AUD2HTX_CTRL_EN, AUD2HTX_CTRL_EN);
+		regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
+				   AUD2HTX_CTRE_DE, AUD2HTX_CTRE_DE);
+		break;
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
+				   AUD2HTX_CTRE_DE, 0);
+		regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL,
+				   AUD2HTX_CTRL_EN, 0);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static const struct snd_soc_dai_ops fsl_aud2htx_dai_ops = {
+	.trigger	= fsl_aud2htx_trigger,
+};
+
+static int fsl_aud2htx_dai_probe(struct snd_soc_dai *cpu_dai)
+{
+	struct fsl_aud2htx *aud2htx = dev_get_drvdata(cpu_dai->dev);
+
+	/* DMA request when number of entries < WTMK_LOW */
+	regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
+			   AUD2HTX_CTRE_DT_MASK, 0);
+
+	/* Disable interrupts*/
+	regmap_update_bits(aud2htx->regmap, AUD2HTX_IRQ_MASK,
+			   AUD2HTX_WM_HIGH_IRQ_MASK |
+			   AUD2HTX_WM_LOW_IRQ_MASK |
+			   AUD2HTX_OVF_MASK,
+			   AUD2HTX_WM_HIGH_IRQ_MASK |
+			   AUD2HTX_WM_LOW_IRQ_MASK |
+			   AUD2HTX_OVF_MASK);
+
+	/* Configure watermark */
+	regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
+			   AUD2HTX_CTRE_WL_MASK,
+			   AUD2HTX_WTMK_LOW << AUD2HTX_CTRE_WL_SHIFT);
+	regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
+			   AUD2HTX_CTRE_WH_MASK,
+			   AUD2HTX_WTMK_HIGH << AUD2HTX_CTRE_WH_SHIFT);
+
+	snd_soc_dai_init_dma_data(cpu_dai, &aud2htx->dma_params_tx,
+				  &aud2htx->dma_params_rx);
+
+	return 0;
+}
+
+static struct snd_soc_dai_driver fsl_aud2htx_dai = {
+	.probe = fsl_aud2htx_dai_probe,
+	.playback = {
+		.stream_name = "CPU-Playback",
+		.channels_min = 1,
+		.channels_max = 8,
+		.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,
+		.formats = FSL_AUD2HTX_FORMATS,
+	},
+	.ops = &fsl_aud2htx_dai_ops,
+};
+
+static const struct snd_soc_component_driver fsl_aud2htx_component = {
+	.name	= "fsl-aud2htx",
+};
+
+static const struct reg_default fsl_aud2htx_reg_defaults[] = {
+	{AUD2HTX_CTRL,		0x00000000},
+	{AUD2HTX_CTRL_EXT,	0x00000000},
+	{AUD2HTX_WR,		0x00000000},
+	{AUD2HTX_STATUS,	0x00000000},
+	{AUD2HTX_IRQ_NOMASK,	0x00000000},
+	{AUD2HTX_IRQ_MASKED,	0x00000000},
+	{AUD2HTX_IRQ_MASK,	0x00000000},
+};
+
+static bool fsl_aud2htx_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case AUD2HTX_CTRL:
+	case AUD2HTX_CTRL_EXT:
+	case AUD2HTX_STATUS:
+	case AUD2HTX_IRQ_NOMASK:
+	case AUD2HTX_IRQ_MASKED:
+	case AUD2HTX_IRQ_MASK:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool fsl_aud2htx_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case AUD2HTX_CTRL:
+	case AUD2HTX_CTRL_EXT:
+	case AUD2HTX_WR:
+	case AUD2HTX_IRQ_NOMASK:
+	case AUD2HTX_IRQ_MASKED:
+	case AUD2HTX_IRQ_MASK:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool fsl_aud2htx_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case AUD2HTX_STATUS:
+	case AUD2HTX_IRQ_NOMASK:
+	case AUD2HTX_IRQ_MASKED:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config fsl_aud2htx_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+
+	.max_register = AUD2HTX_IRQ_MASK,
+	.reg_defaults = fsl_aud2htx_reg_defaults,
+	.num_reg_defaults = ARRAY_SIZE(fsl_aud2htx_reg_defaults),
+	.readable_reg = fsl_aud2htx_readable_reg,
+	.volatile_reg = fsl_aud2htx_volatile_reg,
+	.writeable_reg = fsl_aud2htx_writeable_reg,
+	.cache_type = REGCACHE_RBTREE,
+};
+
+static const struct of_device_id fsl_aud2htx_dt_ids[] = {
+	{ .compatible = "fsl,imx8mp-aud2htx",},
+	{}
+};
+MODULE_DEVICE_TABLE(of, fsl_aud2htx_dt_ids);
+
+static irqreturn_t fsl_aud2htx_isr(int irq, void *dev_id)
+{
+	return IRQ_HANDLED;
+}
+
+static int fsl_aud2htx_probe(struct platform_device *pdev)
+{
+	struct fsl_aud2htx *aud2htx;
+	struct resource *res;
+	void __iomem *regs;
+	int ret, irq;
+
+	aud2htx = devm_kzalloc(&pdev->dev, sizeof(*aud2htx), GFP_KERNEL);
+	if (!aud2htx)
+		return -ENOMEM;
+
+	aud2htx->pdev = pdev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(regs)) {
+		dev_err(&pdev->dev, "failed ioremap\n");
+		return PTR_ERR(regs);
+	}
+
+	aud2htx->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
+						&fsl_aud2htx_regmap_config);
+	if (IS_ERR(aud2htx->regmap)) {
+		dev_err(&pdev->dev, "failed to init regmap");
+		return PTR_ERR(aud2htx->regmap);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "no irq for node %s\n",
+			dev_name(&pdev->dev));
+		return irq;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, fsl_aud2htx_isr, 0,
+			       dev_name(&pdev->dev), aud2htx);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to claim irq %u: %d\n", irq, ret);
+		return ret;
+	}
+
+	aud2htx->bus_clk = devm_clk_get(&pdev->dev, "bus");
+	if (IS_ERR(aud2htx->bus_clk)) {
+		dev_err(&pdev->dev, "failed to get mem clock\n");
+		return PTR_ERR(aud2htx->bus_clk);
+	}
+
+	aud2htx->dma_params_tx.chan_name = "tx";
+	aud2htx->dma_params_tx.maxburst = AUD2HTX_MAXBURST;
+	aud2htx->dma_params_tx.addr = res->start + AUD2HTX_WR;
+
+	platform_set_drvdata(pdev, aud2htx);
+	pm_runtime_enable(&pdev->dev);
+
+	regcache_cache_only(aud2htx->regmap, true);
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+					      &fsl_aud2htx_component,
+					      &fsl_aud2htx_dai, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register ASoC DAI\n");
+		return ret;
+	}
+
+	ret = imx_pcm_dma_init(pdev, IMX_DEFAULT_DMABUF_SIZE);
+	if (ret)
+		dev_err(&pdev->dev, "failed to init imx pcm dma: %d\n", ret);
+
+	return ret;
+}
+
+static int fsl_aud2htx_remove(struct platform_device *pdev)
+{
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+static int fsl_aud2htx_runtime_suspend(struct device *dev)
+{
+	struct fsl_aud2htx *aud2htx = dev_get_drvdata(dev);
+
+	regcache_cache_only(aud2htx->regmap, true);
+	clk_disable_unprepare(aud2htx->bus_clk);
+
+	return 0;
+}
+
+static int fsl_aud2htx_runtime_resume(struct device *dev)
+{
+	struct fsl_aud2htx *aud2htx = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(aud2htx->bus_clk);
+	if (ret)
+		return ret;
+
+	regcache_cache_only(aud2htx->regmap, false);
+	regcache_mark_dirty(aud2htx->regmap);
+	regcache_sync(aud2htx->regmap);
+
+	return 0;
+}
+
+static const struct dev_pm_ops fsl_aud2htx_pm_ops = {
+	SET_RUNTIME_PM_OPS(fsl_aud2htx_runtime_suspend,
+			   fsl_aud2htx_runtime_resume,
+			   NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+};
+
+static struct platform_driver fsl_aud2htx_driver = {
+	.probe = fsl_aud2htx_probe,
+	.remove = fsl_aud2htx_remove,
+	.driver = {
+		.name = "fsl-aud2htx",
+		.pm = &fsl_aud2htx_pm_ops,
+		.of_match_table = fsl_aud2htx_dt_ids,
+	},
+};
+module_platform_driver(fsl_aud2htx_driver);
+
+MODULE_AUTHOR("Shengjiu Wang <Shengjiu.Wang@nxp.com>");
+MODULE_DESCRIPTION("NXP AUD2HTX driver");
+MODULE_LICENSE("GPL v2");