1 files changed, 277 insertions, 0 deletions
diff --git a/sound/soc/adi/axi-i2s.c b/sound/soc/adi/axi-i2s.c
new file mode 100644
index 000000000..4c2338172
--- /dev/null
+++ b/sound/soc/adi/axi-i2s.c
@@ -0,0 +1,277 @@
+/*
+ * Copyright (C) 2012-2013, Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/clk.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.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>
+
+#define AXI_I2S_REG_RESET	0x00
+#define AXI_I2S_REG_CTRL	0x04
+#define AXI_I2S_REG_CLK_CTRL	0x08
+#define AXI_I2S_REG_STATUS	0x10
+
+#define AXI_I2S_REG_RX_FIFO	0x28
+#define AXI_I2S_REG_TX_FIFO	0x2C
+
+#define AXI_I2S_RESET_GLOBAL	BIT(0)
+#define AXI_I2S_RESET_TX_FIFO	BIT(1)
+#define AXI_I2S_RESET_RX_FIFO	BIT(2)
+
+#define AXI_I2S_CTRL_TX_EN	BIT(0)
+#define AXI_I2S_CTRL_RX_EN	BIT(1)
+
+/* The frame size is configurable, but for now we always set it 64 bit */
+#define AXI_I2S_BITS_PER_FRAME 64
+
+struct axi_i2s {
+	struct regmap *regmap;
+	struct clk *clk;
+	struct clk *clk_ref;
+
+	struct snd_soc_dai_driver dai_driver;
+
+	struct snd_dmaengine_dai_dma_data capture_dma_data;
+	struct snd_dmaengine_dai_dma_data playback_dma_data;
+
+	struct snd_ratnum ratnum;
+	struct snd_pcm_hw_constraint_ratnums rate_constraints;
+};
+
+static int axi_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
+	struct snd_soc_dai *dai)
+{
+	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+	unsigned int mask, val;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		mask = AXI_I2S_CTRL_RX_EN;
+	else
+		mask = AXI_I2S_CTRL_TX_EN;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		val = mask;
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		val = 0;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	regmap_update_bits(i2s->regmap, AXI_I2S_REG_CTRL, mask, val);
+
+	return 0;
+}
+
+static int axi_i2s_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+	unsigned int bclk_div, word_size;
+	unsigned int bclk_rate;
+
+	bclk_rate = params_rate(params) * AXI_I2S_BITS_PER_FRAME;
+
+	word_size = AXI_I2S_BITS_PER_FRAME / 2 - 1;
+	bclk_div = DIV_ROUND_UP(clk_get_rate(i2s->clk_ref), bclk_rate) / 2 - 1;
+
+	regmap_write(i2s->regmap, AXI_I2S_REG_CLK_CTRL, (word_size << 16) |
+		bclk_div);
+
+	return 0;
+}
+
+static int axi_i2s_startup(struct snd_pcm_substream *substream,
+	struct snd_soc_dai *dai)
+{
+	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+	uint32_t mask;
+	int ret;
+
+	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+		mask = AXI_I2S_RESET_RX_FIFO;
+	else
+		mask = AXI_I2S_RESET_TX_FIFO;
+
+	regmap_write(i2s->regmap, AXI_I2S_REG_RESET, mask);
+
+	ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
+			   SNDRV_PCM_HW_PARAM_RATE,
+			   &i2s->rate_constraints);
+	if (ret)
+		return ret;
+
+	return clk_prepare_enable(i2s->clk_ref);
+}
+
+static void axi_i2s_shutdown(struct snd_pcm_substream *substream,
+	struct snd_soc_dai *dai)
+{
+	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+
+	clk_disable_unprepare(i2s->clk_ref);
+}
+
+static int axi_i2s_dai_probe(struct snd_soc_dai *dai)
+{
+	struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+
+	snd_soc_dai_init_dma_data(dai, &i2s->playback_dma_data,
+		&i2s->capture_dma_data);
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops axi_i2s_dai_ops = {
+	.startup = axi_i2s_startup,
+	.shutdown = axi_i2s_shutdown,
+	.trigger = axi_i2s_trigger,
+	.hw_params = axi_i2s_hw_params,
+};
+
+static struct snd_soc_dai_driver axi_i2s_dai = {
+	.probe = axi_i2s_dai_probe,
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_KNOT,
+		.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
+	},
+	.capture = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_KNOT,
+		.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
+	},
+	.ops = &axi_i2s_dai_ops,
+	.symmetric_rates = 1,
+};
+
+static const struct snd_soc_component_driver axi_i2s_component = {
+	.name = "axi-i2s",
+};
+
+static const struct regmap_config axi_i2s_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.max_register = AXI_I2S_REG_STATUS,
+};
+
+static int axi_i2s_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct axi_i2s *i2s;
+	void __iomem *base;
+	int ret;
+
+	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
+	if (!i2s)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, i2s);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+		&axi_i2s_regmap_config);
+	if (IS_ERR(i2s->regmap))
+		return PTR_ERR(i2s->regmap);
+
+	i2s->clk = devm_clk_get(&pdev->dev, "axi");
+	if (IS_ERR(i2s->clk))
+		return PTR_ERR(i2s->clk);
+
+	i2s->clk_ref = devm_clk_get(&pdev->dev, "ref");
+	if (IS_ERR(i2s->clk_ref))
+		return PTR_ERR(i2s->clk_ref);
+
+	ret = clk_prepare_enable(i2s->clk);
+	if (ret)
+		return ret;
+
+	i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
+	i2s->playback_dma_data.addr_width = 4;
+	i2s->playback_dma_data.maxburst = 1;
+
+	i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
+	i2s->capture_dma_data.addr_width = 4;
+	i2s->capture_dma_data.maxburst = 1;
+
+	i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME;
+	i2s->ratnum.den_step = 1;
+	i2s->ratnum.den_min = 1;
+	i2s->ratnum.den_max = 64;
+
+	i2s->rate_constraints.rats = &i2s->ratnum;
+	i2s->rate_constraints.nrats = 1;
+
+	regmap_write(i2s->regmap, AXI_I2S_REG_RESET, AXI_I2S_RESET_GLOBAL);
+
+	ret = devm_snd_soc_register_component(&pdev->dev, &axi_i2s_component,
+					 &axi_i2s_dai, 1);
+	if (ret)
+		goto err_clk_disable;
+
+	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+	if (ret)
+		goto err_clk_disable;
+
+	return 0;
+
+err_clk_disable:
+	clk_disable_unprepare(i2s->clk);
+	return ret;
+}
+
+static int axi_i2s_dev_remove(struct platform_device *pdev)
+{
+	struct axi_i2s *i2s = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(i2s->clk);
+
+	return 0;
+}
+
+static const struct of_device_id axi_i2s_of_match[] = {
+	{ .compatible = "adi,axi-i2s-1.00.a", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, axi_i2s_of_match);
+
+static struct platform_driver axi_i2s_driver = {
+	.driver = {
+		.name = "axi-i2s",
+		.of_match_table = axi_i2s_of_match,
+	},
+	.probe = axi_i2s_probe,
+	.remove = axi_i2s_dev_remove,
+};
+module_platform_driver(axi_i2s_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("AXI I2S driver");
+MODULE_LICENSE("GPL");