ASoC: img: Add driver for I2S output controller

Add driver for Imagination Technologies I2S output
controller

Signed-off-by: Damien.Horsley <Damien.Horsley@imgtec.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 565 insertions, 0 deletions

diff --git a/sound/soc/img/img-i2s-out.c b/sound/soc/img/img-i2s-out.c
new file mode 100644
index 000000000000..5f997135a8ae
--- /dev/null
+++ b/sound/soc/img/img-i2s-out.c
@@ -0,0 +1,565 @@
+/*
+ * IMG I2S output controller driver
+ *
+ * Copyright (C) 2015 Imagination Technologies Ltd.
+ *
+ * Author: Damien Horsley <Damien.Horsley@imgtec.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#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/pm_runtime.h>
+#include <linux/reset.h>
+
+#include <sound/core.h>
+#include <sound/dmaengine_pcm.h>
+#include <sound/initval.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define IMG_I2S_OUT_TX_FIFO			0x0
+
+#define IMG_I2S_OUT_CTL				0x4
+#define IMG_I2S_OUT_CTL_DATA_EN_MASK		BIT(24)
+#define IMG_I2S_OUT_CTL_ACTIVE_CHAN_MASK	0xffe000
+#define IMG_I2S_OUT_CTL_ACTIVE_CHAN_SHIFT	13
+#define IMG_I2S_OUT_CTL_FRM_SIZE_MASK		BIT(8)
+#define IMG_I2S_OUT_CTL_MASTER_MASK		BIT(6)
+#define IMG_I2S_OUT_CTL_CLK_MASK		BIT(5)
+#define IMG_I2S_OUT_CTL_CLK_EN_MASK		BIT(4)
+#define IMG_I2S_OUT_CTL_FRM_CLK_POL_MASK	BIT(3)
+#define IMG_I2S_OUT_CTL_BCLK_POL_MASK		BIT(2)
+#define IMG_I2S_OUT_CTL_ME_MASK			BIT(0)
+
+#define IMG_I2S_OUT_CH_CTL			0x4
+#define IMG_I2S_OUT_CHAN_CTL_CH_MASK		BIT(11)
+#define IMG_I2S_OUT_CHAN_CTL_LT_MASK		BIT(10)
+#define IMG_I2S_OUT_CHAN_CTL_FMT_MASK		0xf0
+#define IMG_I2S_OUT_CHAN_CTL_FMT_SHIFT		4
+#define IMG_I2S_OUT_CHAN_CTL_JUST_MASK		BIT(3)
+#define IMG_I2S_OUT_CHAN_CTL_CLKT_MASK		BIT(1)
+#define IMG_I2S_OUT_CHAN_CTL_ME_MASK		BIT(0)
+
+#define IMG_I2S_OUT_CH_STRIDE			0x20
+
+struct img_i2s_out {
+	void __iomem *base;
+	struct clk *clk_sys;
+	struct clk *clk_ref;
+	struct snd_dmaengine_dai_dma_data dma_data;
+	struct device *dev;
+	unsigned int max_i2s_chan;
+	void __iomem *channel_base;
+	bool force_clk_active;
+	unsigned int active_channels;
+	struct reset_control *rst;
+	struct snd_soc_dai_driver dai_driver;
+};
+
+static int img_i2s_out_suspend(struct device *dev)
+{
+	struct img_i2s_out *i2s = dev_get_drvdata(dev);
+
+	if (!i2s->force_clk_active)
+		clk_disable_unprepare(i2s->clk_ref);
+
+	return 0;
+}
+
+static int img_i2s_out_resume(struct device *dev)
+{
+	struct img_i2s_out *i2s = dev_get_drvdata(dev);
+	int ret;
+
+	if (!i2s->force_clk_active) {
+		ret = clk_prepare_enable(i2s->clk_ref);
+		if (ret) {
+			dev_err(dev, "clk_enable failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static inline void img_i2s_out_writel(struct img_i2s_out *i2s, u32 val,
+					u32 reg)
+{
+	writel(val, i2s->base + reg);
+}
+
+static inline u32 img_i2s_out_readl(struct img_i2s_out *i2s, u32 reg)
+{
+	return readl(i2s->base + reg);
+}
+
+static inline void img_i2s_out_ch_writel(struct img_i2s_out *i2s,
+					u32 chan, u32 val, u32 reg)
+{
+	writel(val, i2s->channel_base + (chan * IMG_I2S_OUT_CH_STRIDE) + reg);
+}
+
+static inline u32 img_i2s_out_ch_readl(struct img_i2s_out *i2s, u32 chan,
+					u32 reg)
+{
+	return readl(i2s->channel_base + (chan * IMG_I2S_OUT_CH_STRIDE) + reg);
+}
+
+static inline void img_i2s_out_ch_disable(struct img_i2s_out *i2s, u32 chan)
+{
+	u32 reg;
+
+	reg = img_i2s_out_ch_readl(i2s, chan, IMG_I2S_OUT_CH_CTL);
+	reg &= ~IMG_I2S_OUT_CHAN_CTL_ME_MASK;
+	img_i2s_out_ch_writel(i2s, chan, reg, IMG_I2S_OUT_CH_CTL);
+}
+
+static inline void img_i2s_out_ch_enable(struct img_i2s_out *i2s, u32 chan)
+{
+	u32 reg;
+
+	reg = img_i2s_out_ch_readl(i2s, chan, IMG_I2S_OUT_CH_CTL);
+	reg |= IMG_I2S_OUT_CHAN_CTL_ME_MASK;
+	img_i2s_out_ch_writel(i2s, chan, reg, IMG_I2S_OUT_CH_CTL);
+}
+
+static inline void img_i2s_out_disable(struct img_i2s_out *i2s)
+{
+	u32 reg;
+
+	reg = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL);
+	reg &= ~IMG_I2S_OUT_CTL_ME_MASK;
+	img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+}
+
+static inline void img_i2s_out_enable(struct img_i2s_out *i2s)
+{
+	u32 reg;
+
+	reg = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL);
+	reg |= IMG_I2S_OUT_CTL_ME_MASK;
+	img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+}
+
+static void img_i2s_out_reset(struct img_i2s_out *i2s)
+{
+	int i;
+	u32 core_ctl, chan_ctl;
+
+	core_ctl = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL) &
+			~IMG_I2S_OUT_CTL_ME_MASK &
+			~IMG_I2S_OUT_CTL_DATA_EN_MASK;
+
+	if (!i2s->force_clk_active)
+		core_ctl &= ~IMG_I2S_OUT_CTL_CLK_EN_MASK;
+
+	chan_ctl = img_i2s_out_ch_readl(i2s, 0, IMG_I2S_OUT_CH_CTL) &
+			~IMG_I2S_OUT_CHAN_CTL_ME_MASK;
+
+	reset_control_assert(i2s->rst);
+	reset_control_deassert(i2s->rst);
+
+	for (i = 0; i < i2s->max_i2s_chan; i++)
+		img_i2s_out_ch_writel(i2s, i, chan_ctl, IMG_I2S_OUT_CH_CTL);
+
+	for (i = 0; i < i2s->active_channels; i++)
+		img_i2s_out_ch_enable(i2s, i);
+
+	img_i2s_out_writel(i2s, core_ctl, IMG_I2S_OUT_CTL);
+	img_i2s_out_enable(i2s);
+}
+
+static int img_i2s_out_trigger(struct snd_pcm_substream *substream, int cmd,
+	struct snd_soc_dai *dai)
+{
+	struct img_i2s_out *i2s = snd_soc_dai_get_drvdata(dai);
+	u32 reg;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		reg = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL);
+		if (!i2s->force_clk_active)
+			reg |= IMG_I2S_OUT_CTL_CLK_EN_MASK;
+		reg |= IMG_I2S_OUT_CTL_DATA_EN_MASK;
+		img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		img_i2s_out_reset(i2s);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int img_i2s_out_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+	struct img_i2s_out *i2s = snd_soc_dai_get_drvdata(dai);
+	unsigned int channels, i2s_channels;
+	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
+	int i;
+	u32 reg, control_mask, control_set = 0;
+	snd_pcm_format_t format;
+
+	rate = params_rate(params);
+	format = params_format(params);
+	channels = params_channels(params);
+	i2s_channels = channels / 2;
+
+	if (format != SNDRV_PCM_FORMAT_S32_LE)
+		return -EINVAL;
+
+	if ((channels < 2) ||
+	    (channels > (i2s->max_i2s_chan * 2)) ||
+	    (channels % 2))
+		return -EINVAL;
+
+	pre_div_a = clk_round_rate(i2s->clk_ref, rate * 256);
+	if (pre_div_a < 0)
+		return pre_div_a;
+	pre_div_b = clk_round_rate(i2s->clk_ref, rate * 384);
+	if (pre_div_b < 0)
+		return pre_div_b;
+
+	diff_a = abs((pre_div_a / 256) - rate);
+	diff_b = abs((pre_div_b / 384) - rate);
+
+	/* If diffs are equal, use lower clock rate */
+	if (diff_a > diff_b)
+		clk_set_rate(i2s->clk_ref, pre_div_b);
+	else
+		clk_set_rate(i2s->clk_ref, pre_div_a);
+
+	/*
+	 * Another driver (eg alsa machine driver) may have rejected the above
+	 * change. Get the current rate and set the register bit according to
+	 * the new minimum diff
+	 */
+	clk_rate = clk_get_rate(i2s->clk_ref);
+
+	diff_a = abs((clk_rate / 256) - rate);
+	diff_b = abs((clk_rate / 384) - rate);
+
+	if (diff_a > diff_b)
+		control_set |= IMG_I2S_OUT_CTL_CLK_MASK;
+
+	control_set |= ((i2s_channels - 1) <<
+		       IMG_I2S_OUT_CTL_ACTIVE_CHAN_SHIFT) &
+		       IMG_I2S_OUT_CTL_ACTIVE_CHAN_MASK;
+
+	control_mask = IMG_I2S_OUT_CTL_CLK_MASK |
+		       IMG_I2S_OUT_CTL_ACTIVE_CHAN_MASK;
+
+	img_i2s_out_disable(i2s);
+
+	reg = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL);
+	reg = (reg & ~control_mask) | control_set;
+	img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+
+	for (i = 0; i < i2s_channels; i++)
+		img_i2s_out_ch_enable(i2s, i);
+
+	for (; i < i2s->max_i2s_chan; i++)
+		img_i2s_out_ch_disable(i2s, i);
+
+	img_i2s_out_enable(i2s);
+
+	i2s->active_channels = i2s_channels;
+
+	return 0;
+}
+
+static int img_i2s_out_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
+{
+	struct img_i2s_out *i2s = snd_soc_dai_get_drvdata(dai);
+	int i;
+	bool force_clk_active;
+	u32 chan_control_mask, control_mask, chan_control_set = 0;
+	u32 reg, control_set = 0;
+
+	force_clk_active = ((fmt & SND_SOC_DAIFMT_CLOCK_MASK) ==
+			SND_SOC_DAIFMT_CONT);
+
+	if (force_clk_active)
+		control_set |= IMG_I2S_OUT_CTL_CLK_EN_MASK;
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		control_set |= IMG_I2S_OUT_CTL_MASTER_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		control_set |= IMG_I2S_OUT_CTL_BCLK_POL_MASK;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		control_set |= IMG_I2S_OUT_CTL_BCLK_POL_MASK;
+		control_set |= IMG_I2S_OUT_CTL_FRM_CLK_POL_MASK;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		control_set |= IMG_I2S_OUT_CTL_FRM_CLK_POL_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		chan_control_set |= IMG_I2S_OUT_CHAN_CTL_CLKT_MASK;
+		break;
+	case SND_SOC_DAIFMT_LEFT_J:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	control_mask = IMG_I2S_OUT_CTL_CLK_EN_MASK |
+		       IMG_I2S_OUT_CTL_MASTER_MASK |
+		       IMG_I2S_OUT_CTL_BCLK_POL_MASK |
+		       IMG_I2S_OUT_CTL_FRM_CLK_POL_MASK;
+
+	chan_control_mask = IMG_I2S_OUT_CHAN_CTL_CLKT_MASK;
+
+	img_i2s_out_disable(i2s);
+
+	reg = img_i2s_out_readl(i2s, IMG_I2S_OUT_CTL);
+	reg = (reg & ~control_mask) | control_set;
+	img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+
+	for (i = 0; i < i2s->active_channels; i++)
+		img_i2s_out_ch_disable(i2s, i);
+
+	for (i = 0; i < i2s->max_i2s_chan; i++) {
+		reg = img_i2s_out_ch_readl(i2s, i, IMG_I2S_OUT_CH_CTL);
+		reg = (reg & ~chan_control_mask) | chan_control_set;
+		img_i2s_out_ch_writel(i2s, i, reg, IMG_I2S_OUT_CH_CTL);
+	}
+
+	for (i = 0; i < i2s->active_channels; i++)
+		img_i2s_out_ch_enable(i2s, i);
+
+	img_i2s_out_enable(i2s);
+
+	i2s->force_clk_active = force_clk_active;
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops img_i2s_out_dai_ops = {
+	.trigger = img_i2s_out_trigger,
+	.hw_params = img_i2s_out_hw_params,
+	.set_fmt = img_i2s_out_set_fmt
+};
+
+static int img_i2s_out_dai_probe(struct snd_soc_dai *dai)
+{
+	struct img_i2s_out *i2s = snd_soc_dai_get_drvdata(dai);
+
+	snd_soc_dai_init_dma_data(dai, &i2s->dma_data, NULL);
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver img_i2s_out_component = {
+	.name = "img-i2s-out"
+};
+
+static int img_i2s_out_dma_prepare_slave_config(struct snd_pcm_substream *st,
+	struct snd_pcm_hw_params *params, struct dma_slave_config *sc)
+{
+	unsigned int i2s_channels = params_channels(params) / 2;
+	struct snd_soc_pcm_runtime *rtd = st->private_data;
+	struct snd_dmaengine_dai_dma_data *dma_data;
+	int ret;
+
+	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, st);
+
+	ret = snd_hwparams_to_dma_slave_config(st, params, sc);
+	if (ret)
+		return ret;
+
+	sc->dst_addr = dma_data->addr;
+	sc->dst_addr_width = dma_data->addr_width;
+	sc->dst_maxburst = 4 * i2s_channels;
+
+	return 0;
+}
+
+static const struct snd_dmaengine_pcm_config img_i2s_out_dma_config = {
+	.prepare_slave_config = img_i2s_out_dma_prepare_slave_config
+};
+
+static int img_i2s_out_probe(struct platform_device *pdev)
+{
+	struct img_i2s_out *i2s;
+	struct resource *res;
+	void __iomem *base;
+	int i, ret;
+	unsigned int max_i2s_chan_pow_2;
+	u32 reg;
+	struct device *dev = &pdev->dev;
+
+	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
+	if (!i2s)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, i2s);
+
+	i2s->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	i2s->base = base;
+
+	if (of_property_read_u32(pdev->dev.of_node, "img,i2s-channels",
+			&i2s->max_i2s_chan)) {
+		dev_err(&pdev->dev, "No img,i2s-channels property\n");
+		return -EINVAL;
+	}
+
+	max_i2s_chan_pow_2 = 1 << get_count_order(i2s->max_i2s_chan);
+
+	i2s->channel_base = base + (max_i2s_chan_pow_2 * 0x20);
+
+	i2s->rst = devm_reset_control_get(&pdev->dev, "rst");
+	if (IS_ERR(i2s->rst)) {
+		if (PTR_ERR(i2s->rst) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "No top level reset found\n");
+		return PTR_ERR(i2s->rst);
+	}
+
+	i2s->clk_sys = devm_clk_get(&pdev->dev, "sys");
+	if (IS_ERR(i2s->clk_sys)) {
+		if (PTR_ERR(i2s->clk_sys) != -EPROBE_DEFER)
+			dev_err(dev, "Failed to acquire clock 'sys'\n");
+		return PTR_ERR(i2s->clk_sys);
+	}
+
+	i2s->clk_ref = devm_clk_get(&pdev->dev, "ref");
+	if (IS_ERR(i2s->clk_ref)) {
+		if (PTR_ERR(i2s->clk_ref) != -EPROBE_DEFER)
+			dev_err(dev, "Failed to acquire clock 'ref'\n");
+		return PTR_ERR(i2s->clk_ref);
+	}
+
+	ret = clk_prepare_enable(i2s->clk_sys);
+	if (ret)
+		return ret;
+
+	reg = IMG_I2S_OUT_CTL_FRM_SIZE_MASK;
+	img_i2s_out_writel(i2s, reg, IMG_I2S_OUT_CTL);
+
+	reg = IMG_I2S_OUT_CHAN_CTL_JUST_MASK |
+		IMG_I2S_OUT_CHAN_CTL_LT_MASK |
+		IMG_I2S_OUT_CHAN_CTL_CH_MASK |
+		(8 << IMG_I2S_OUT_CHAN_CTL_FMT_SHIFT);
+
+	for (i = 0; i < i2s->max_i2s_chan; i++)
+		img_i2s_out_ch_writel(i2s, i, reg, IMG_I2S_OUT_CH_CTL);
+
+	img_i2s_out_reset(i2s);
+
+	pm_runtime_enable(&pdev->dev);
+	if (!pm_runtime_enabled(&pdev->dev)) {
+		ret = img_i2s_out_resume(&pdev->dev);
+		if (ret)
+			goto err_pm_disable;
+	}
+
+	i2s->active_channels = 1;
+	i2s->dma_data.addr = res->start + IMG_I2S_OUT_TX_FIFO;
+	i2s->dma_data.addr_width = 4;
+	i2s->dma_data.maxburst = 4;
+
+	i2s->dai_driver.probe = img_i2s_out_dai_probe;
+	i2s->dai_driver.playback.channels_min = 2;
+	i2s->dai_driver.playback.channels_max = i2s->max_i2s_chan * 2;
+	i2s->dai_driver.playback.rates = SNDRV_PCM_RATE_8000_192000;
+	i2s->dai_driver.playback.formats = SNDRV_PCM_FMTBIT_S32_LE;
+	i2s->dai_driver.ops = &img_i2s_out_dai_ops;
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+			&img_i2s_out_component, &i2s->dai_driver, 1);
+	if (ret)
+		goto err_suspend;
+
+	ret = devm_snd_dmaengine_pcm_register(&pdev->dev,
+			&img_i2s_out_dma_config, 0);
+	if (ret)
+		goto err_suspend;
+
+	return 0;
+
+err_suspend:
+	if (!pm_runtime_status_suspended(&pdev->dev))
+		img_i2s_out_suspend(&pdev->dev);
+err_pm_disable:
+	pm_runtime_disable(&pdev->dev);
+	clk_disable_unprepare(i2s->clk_sys);
+
+	return ret;
+}
+
+static int img_i2s_out_dev_remove(struct platform_device *pdev)
+{
+	struct img_i2s_out *i2s = platform_get_drvdata(pdev);
+
+	pm_runtime_disable(&pdev->dev);
+	if (!pm_runtime_status_suspended(&pdev->dev))
+		img_i2s_out_suspend(&pdev->dev);
+
+	clk_disable_unprepare(i2s->clk_sys);
+
+	return 0;
+}
+
+static const struct of_device_id img_i2s_out_of_match[] = {
+	{ .compatible = "img,i2s-out" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, img_i2s_out_of_match);
+
+static const struct dev_pm_ops img_i2s_out_pm_ops = {
+	SET_RUNTIME_PM_OPS(img_i2s_out_suspend,
+			   img_i2s_out_resume, NULL)
+};
+
+static struct platform_driver img_i2s_out_driver = {
+	.driver = {
+		.name = "img-i2s-out",
+		.of_match_table = img_i2s_out_of_match,
+		.pm = &img_i2s_out_pm_ops
+	},
+	.probe = img_i2s_out_probe,
+	.remove = img_i2s_out_dev_remove
+};
+module_platform_driver(img_i2s_out_driver);
+
+MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
+MODULE_DESCRIPTION("IMG I2S Output Driver");
+MODULE_LICENSE("GPL v2");