1 files changed, 430 insertions, 0 deletions

diff --git a/sound/soc/tegra/tegra20_spdif.c b/sound/soc/tegra/tegra20_spdif.c
new file mode 100644
index 000000000..b0670aa4d
--- /dev/null
+++ b/sound/soc/tegra/tegra20_spdif.c
@@ -0,0 +1,430 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * tegra20_spdif.c - Tegra20 SPDIF driver
+ *
+ * Author: Stephen Warren <swarren@nvidia.com>
+ * Copyright (C) 2011-2012 - NVIDIA, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.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/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/dmaengine_pcm.h>
+
+#include "tegra20_spdif.h"
+
+static __maybe_unused int tegra20_spdif_runtime_suspend(struct device *dev)
+{
+	struct tegra20_spdif *spdif = dev_get_drvdata(dev);
+
+	regcache_cache_only(spdif->regmap, true);
+
+	clk_disable_unprepare(spdif->clk_spdif_out);
+
+	return 0;
+}
+
+static __maybe_unused int tegra20_spdif_runtime_resume(struct device *dev)
+{
+	struct tegra20_spdif *spdif = dev_get_drvdata(dev);
+	int ret;
+
+	ret = reset_control_assert(spdif->reset);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(spdif->clk_spdif_out);
+	if (ret) {
+		dev_err(dev, "clk_enable failed: %d\n", ret);
+		return ret;
+	}
+
+	usleep_range(10, 100);
+
+	ret = reset_control_deassert(spdif->reset);
+	if (ret)
+		goto disable_clocks;
+
+	regcache_cache_only(spdif->regmap, false);
+	regcache_mark_dirty(spdif->regmap);
+
+	ret = regcache_sync(spdif->regmap);
+	if (ret)
+		goto disable_clocks;
+
+	return 0;
+
+disable_clocks:
+	clk_disable_unprepare(spdif->clk_spdif_out);
+
+	return ret;
+}
+
+static int tegra20_spdif_hw_params(struct snd_pcm_substream *substream,
+				   struct snd_pcm_hw_params *params,
+				   struct snd_soc_dai *dai)
+{
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
+	unsigned int mask = 0, val = 0;
+	int ret, spdifclock;
+	long rate;
+
+	mask |= TEGRA20_SPDIF_CTRL_PACK |
+		TEGRA20_SPDIF_CTRL_BIT_MODE_MASK;
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S16_LE:
+		val |= TEGRA20_SPDIF_CTRL_PACK |
+		       TEGRA20_SPDIF_CTRL_BIT_MODE_16BIT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL, mask, val);
+
+	/*
+	 * FIFO trigger level must be bigger than DMA burst or equal to it,
+	 * otherwise data is discarded on overflow.
+	 */
+	regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_DATA_FIFO_CSR,
+			   TEGRA20_SPDIF_DATA_FIFO_CSR_TX_ATN_LVL_MASK,
+			   TEGRA20_SPDIF_DATA_FIFO_CSR_TX_ATN_LVL_TU4_WORD_FULL);
+
+	switch (params_rate(params)) {
+	case 32000:
+		spdifclock = 4096000;
+		break;
+	case 44100:
+		spdifclock = 5644800;
+		break;
+	case 48000:
+		spdifclock = 6144000;
+		break;
+	case 88200:
+		spdifclock = 11289600;
+		break;
+	case 96000:
+		spdifclock = 12288000;
+		break;
+	case 176400:
+		spdifclock = 22579200;
+		break;
+	case 192000:
+		spdifclock = 24576000;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = clk_set_rate(spdif->clk_spdif_out, spdifclock);
+	if (ret) {
+		dev_err(dai->dev, "Can't set SPDIF clock rate: %d\n", ret);
+		return ret;
+	}
+
+	rate = clk_get_rate(spdif->clk_spdif_out);
+	if (rate != spdifclock)
+		dev_warn_once(dai->dev,
+			      "SPDIF clock rate %d doesn't match requested rate %lu\n",
+			      spdifclock, rate);
+
+	return 0;
+}
+
+static void tegra20_spdif_start_playback(struct tegra20_spdif *spdif)
+{
+	regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL,
+			   TEGRA20_SPDIF_CTRL_TX_EN,
+			   TEGRA20_SPDIF_CTRL_TX_EN);
+}
+
+static void tegra20_spdif_stop_playback(struct tegra20_spdif *spdif)
+{
+	regmap_update_bits(spdif->regmap, TEGRA20_SPDIF_CTRL,
+			   TEGRA20_SPDIF_CTRL_TX_EN, 0);
+}
+
+static int tegra20_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
+				 struct snd_soc_dai *dai)
+{
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		tegra20_spdif_start_playback(spdif);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		tegra20_spdif_stop_playback(spdif);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int tegra20_spdif_filter_rates(struct snd_pcm_hw_params *params,
+				      struct snd_pcm_hw_rule *rule)
+{
+	struct snd_interval *r = hw_param_interval(params, rule->var);
+	struct snd_soc_dai *dai = rule->private;
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
+	struct clk *parent = clk_get_parent(spdif->clk_spdif_out);
+	static const unsigned int rates[] = { 32000, 44100, 48000 };
+	unsigned long i, parent_rate, valid_rates = 0;
+
+	parent_rate = clk_get_rate(parent);
+	if (!parent_rate) {
+		dev_err(dai->dev, "Can't get parent clock rate\n");
+		return -EINVAL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(rates); i++) {
+		if (parent_rate % (rates[i] * 128) == 0)
+			valid_rates |= BIT(i);
+	}
+
+	/*
+	 * At least one rate must be valid, otherwise the parent clock isn't
+	 * audio PLL. Nothing should be filtered in this case.
+	 */
+	if (!valid_rates)
+		valid_rates = BIT(ARRAY_SIZE(rates)) - 1;
+
+	return snd_interval_list(r, ARRAY_SIZE(rates), rates, valid_rates);
+}
+
+static int tegra20_spdif_startup(struct snd_pcm_substream *substream,
+				 struct snd_soc_dai *dai)
+{
+	if (!device_property_read_bool(dai->dev, "nvidia,fixed-parent-rate"))
+		return 0;
+
+	/*
+	 * SPDIF and I2S share audio PLL. HDMI takes audio packets from SPDIF
+	 * and audio may not work on some TVs if clock rate isn't precise.
+	 *
+	 * PLL rate is controlled by I2S side. Filter out audio rates that
+	 * don't match PLL rate at the start of stream to allow both SPDIF
+	 * and I2S work simultaneously, assuming that PLL rate won't be
+	 * changed later on.
+	 */
+	return snd_pcm_hw_rule_add(substream->runtime, 0,
+				   SNDRV_PCM_HW_PARAM_RATE,
+				   tegra20_spdif_filter_rates, dai,
+				   SNDRV_PCM_HW_PARAM_RATE, -1);
+}
+
+static int tegra20_spdif_probe(struct snd_soc_dai *dai)
+{
+	struct tegra20_spdif *spdif = dev_get_drvdata(dai->dev);
+
+	snd_soc_dai_init_dma_data(dai, &spdif->playback_dma_data, NULL);
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops tegra20_spdif_dai_ops = {
+	.probe = tegra20_spdif_probe,
+	.hw_params = tegra20_spdif_hw_params,
+	.trigger = tegra20_spdif_trigger,
+	.startup = tegra20_spdif_startup,
+};
+
+static struct snd_soc_dai_driver tegra20_spdif_dai = {
+	.name = "tegra20-spdif",
+	.playback = {
+		.stream_name = "Playback",
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
+			 SNDRV_PCM_RATE_48000,
+		.formats = SNDRV_PCM_FMTBIT_S16_LE,
+	},
+	.ops = &tegra20_spdif_dai_ops,
+};
+
+static const struct snd_soc_component_driver tegra20_spdif_component = {
+	.name = "tegra20-spdif",
+	.legacy_dai_naming = 1,
+};
+
+static bool tegra20_spdif_wr_rd_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case TEGRA20_SPDIF_CTRL:
+	case TEGRA20_SPDIF_STATUS:
+	case TEGRA20_SPDIF_STROBE_CTRL:
+	case TEGRA20_SPDIF_DATA_FIFO_CSR:
+	case TEGRA20_SPDIF_DATA_OUT:
+	case TEGRA20_SPDIF_DATA_IN:
+	case TEGRA20_SPDIF_CH_STA_RX_A:
+	case TEGRA20_SPDIF_CH_STA_RX_B:
+	case TEGRA20_SPDIF_CH_STA_RX_C:
+	case TEGRA20_SPDIF_CH_STA_RX_D:
+	case TEGRA20_SPDIF_CH_STA_RX_E:
+	case TEGRA20_SPDIF_CH_STA_RX_F:
+	case TEGRA20_SPDIF_CH_STA_TX_A:
+	case TEGRA20_SPDIF_CH_STA_TX_B:
+	case TEGRA20_SPDIF_CH_STA_TX_C:
+	case TEGRA20_SPDIF_CH_STA_TX_D:
+	case TEGRA20_SPDIF_CH_STA_TX_E:
+	case TEGRA20_SPDIF_CH_STA_TX_F:
+	case TEGRA20_SPDIF_USR_STA_RX_A:
+	case TEGRA20_SPDIF_USR_DAT_TX_A:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool tegra20_spdif_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case TEGRA20_SPDIF_STATUS:
+	case TEGRA20_SPDIF_DATA_FIFO_CSR:
+	case TEGRA20_SPDIF_DATA_OUT:
+	case TEGRA20_SPDIF_DATA_IN:
+	case TEGRA20_SPDIF_CH_STA_RX_A:
+	case TEGRA20_SPDIF_CH_STA_RX_B:
+	case TEGRA20_SPDIF_CH_STA_RX_C:
+	case TEGRA20_SPDIF_CH_STA_RX_D:
+	case TEGRA20_SPDIF_CH_STA_RX_E:
+	case TEGRA20_SPDIF_CH_STA_RX_F:
+	case TEGRA20_SPDIF_USR_STA_RX_A:
+	case TEGRA20_SPDIF_USR_DAT_TX_A:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool tegra20_spdif_precious_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case TEGRA20_SPDIF_DATA_OUT:
+	case TEGRA20_SPDIF_DATA_IN:
+	case TEGRA20_SPDIF_USR_STA_RX_A:
+	case TEGRA20_SPDIF_USR_DAT_TX_A:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config tegra20_spdif_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.max_register = TEGRA20_SPDIF_USR_DAT_TX_A,
+	.writeable_reg = tegra20_spdif_wr_rd_reg,
+	.readable_reg = tegra20_spdif_wr_rd_reg,
+	.volatile_reg = tegra20_spdif_volatile_reg,
+	.precious_reg = tegra20_spdif_precious_reg,
+	.cache_type = REGCACHE_FLAT,
+};
+
+static int tegra20_spdif_platform_probe(struct platform_device *pdev)
+{
+	struct tegra20_spdif *spdif;
+	struct resource *mem;
+	void __iomem *regs;
+	int ret;
+
+	spdif = devm_kzalloc(&pdev->dev, sizeof(struct tegra20_spdif),
+			     GFP_KERNEL);
+	if (!spdif)
+		return -ENOMEM;
+
+	dev_set_drvdata(&pdev->dev, spdif);
+
+	spdif->reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+	if (IS_ERR(spdif->reset)) {
+		dev_err(&pdev->dev, "Can't retrieve spdif reset\n");
+		return PTR_ERR(spdif->reset);
+	}
+
+	spdif->clk_spdif_out = devm_clk_get(&pdev->dev, "out");
+	if (IS_ERR(spdif->clk_spdif_out)) {
+		dev_err(&pdev->dev, "Could not retrieve spdif clock\n");
+		return PTR_ERR(spdif->clk_spdif_out);
+	}
+
+	regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	spdif->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
+					      &tegra20_spdif_regmap_config);
+	if (IS_ERR(spdif->regmap)) {
+		dev_err(&pdev->dev, "regmap init failed\n");
+		return PTR_ERR(spdif->regmap);
+	}
+
+	spdif->playback_dma_data.addr = mem->start + TEGRA20_SPDIF_DATA_OUT;
+	spdif->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	spdif->playback_dma_data.maxburst = 4;
+
+	ret = devm_pm_runtime_enable(&pdev->dev);
+	if (ret)
+		return ret;
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+					      &tegra20_spdif_component,
+					      &tegra20_spdif_dai, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_tegra_pcm_platform_register(&pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops tegra20_spdif_pm_ops = {
+	SET_RUNTIME_PM_OPS(tegra20_spdif_runtime_suspend,
+			   tegra20_spdif_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+};
+
+static const struct of_device_id tegra20_spdif_of_match[] = {
+	{ .compatible = "nvidia,tegra20-spdif", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, tegra20_spdif_of_match);
+
+static struct platform_driver tegra20_spdif_driver = {
+	.driver = {
+		.name = "tegra20-spdif",
+		.pm = &tegra20_spdif_pm_ops,
+		.of_match_table = tegra20_spdif_of_match,
+	},
+	.probe = tegra20_spdif_platform_probe,
+};
+module_platform_driver(tegra20_spdif_driver);
+
+MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
+MODULE_DESCRIPTION("Tegra20 SPDIF ASoC driver");
+MODULE_LICENSE("GPL");