ASoC: img: Add driver for SPDIF output controller

Add driver for Imagination Technologies SPDIF output
controller
Signed-off-by: NDamien.Horsley <Damien.Horsley@imgtec.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/img/Kconfig

@@ -34,3 +34,11 @@ config SND_SOC_IMG_SPDIF_IN
 	help
 	  Say Y or M if you want to add support for SPDIF input driver for
 	  Imagination Technologies SPDIF input device.
+
+config SND_SOC_IMG_SPDIF_OUT
+	tristate "Imagination SPDIF Output Device Driver"
+	depends on SND_SOC_IMG
+	select SND_SOC_GENERIC_DMAENGINE_PCM
+	help
+	  Say Y or M if you want to add support for SPDIF out driver for
+	  Imagination Technologies SPDIF out device.

sound/soc/img/Makefile

@@ -2,3 +2,4 @@ obj-$(CONFIG_SND_SOC_IMG_I2S_IN) += img-i2s-in.o
 obj-$(CONFIG_SND_SOC_IMG_I2S_OUT) += img-i2s-out.o
 obj-$(CONFIG_SND_SOC_IMG_PARALLEL_OUT) += img-parallel-out.o
 obj-$(CONFIG_SND_SOC_IMG_SPDIF_IN) += img-spdif-in.o
+obj-$(CONFIG_SND_SOC_IMG_SPDIF_OUT) += img-spdif-out.o

sound/soc/img/img-spdif-out.c

+/*
+ * IMG SPDIF 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_SPDIF_OUT_TX_FIFO		0x0
+
+#define IMG_SPDIF_OUT_CTL		0x4
+#define IMG_SPDIF_OUT_CTL_FS_MASK	BIT(4)
+#define IMG_SPDIF_OUT_CTL_CLK_MASK	BIT(2)
+#define IMG_SPDIF_OUT_CTL_SRT_MASK	BIT(0)
+
+#define IMG_SPDIF_OUT_CSL		0x14
+
+#define IMG_SPDIF_OUT_CSH_UV		0x18
+#define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT	0
+#define IMG_SPDIF_OUT_CSH_UV_CSH_MASK	0xff
+
+struct img_spdif_out {
+	spinlock_t lock;
+	void __iomem *base;
+	struct clk *clk_sys;
+	struct clk *clk_ref;
+	struct snd_dmaengine_dai_dma_data dma_data;
+	struct device *dev;
+	struct reset_control *rst;
+};
+
+static int img_spdif_out_suspend(struct device *dev)
+{
+	struct img_spdif_out *spdif = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(spdif->clk_ref);
+
+	return 0;
+}
+
+static int img_spdif_out_resume(struct device *dev)
+{
+	struct img_spdif_out *spdif = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(spdif->clk_ref);
+	if (ret) {
+		dev_err(dev, "clk_enable failed: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
+				u32 reg)
+{
+	writel(val, spdif->base + reg);
+}
+
+static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
+{
+	return readl(spdif->base + reg);
+}
+
+static void img_spdif_out_reset(struct img_spdif_out *spdif)
+{
+	u32 ctl, status_low, status_high;
+
+	ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
+			~IMG_SPDIF_OUT_CTL_SRT_MASK;
+	status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
+	status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
+
+	reset_control_assert(spdif->rst);
+	reset_control_deassert(spdif->rst);
+
+	img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
+	img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
+	img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
+}
+
+static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
+					struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+	uinfo->count = 1;
+
+	return 0;
+}
+
+static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
+				       struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.iec958.status[0] = 0xff;
+	ucontrol->value.iec958.status[1] = 0xff;
+	ucontrol->value.iec958.status[2] = 0xff;
+	ucontrol->value.iec958.status[3] = 0xff;
+	ucontrol->value.iec958.status[4] = 0xff;
+
+	return 0;
+}
+
+static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
+				  struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 reg;
+	unsigned long flags;
+
+	spin_lock_irqsave(&spdif->lock, flags);
+
+	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
+	ucontrol->value.iec958.status[0] = reg & 0xff;
+	ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
+	ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
+	ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;
+
+	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
+	ucontrol->value.iec958.status[4] =
+		(reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
+		IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
+
+	spin_unlock_irqrestore(&spdif->lock, flags);
+
+	return 0;
+}
+
+static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
+				  struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
+	u32 reg;
+	unsigned long flags;
+
+	reg = ((u32)ucontrol->value.iec958.status[3] << 24);
+	reg |= ((u32)ucontrol->value.iec958.status[2] << 16);
+	reg |= ((u32)ucontrol->value.iec958.status[1] << 8);
+	reg |= (u32)ucontrol->value.iec958.status[0];
+
+	spin_lock_irqsave(&spdif->lock, flags);
+
+	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);
+
+	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
+	reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
+	reg |= (u32)ucontrol->value.iec958.status[4] <<
+			IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
+	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);
+
+	spin_unlock_irqrestore(&spdif->lock, flags);
+
+	return 0;
+}
+
+static struct snd_kcontrol_new img_spdif_out_controls[] = {
+	{
+		.access = SNDRV_CTL_ELEM_ACCESS_READ,
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
+		.info = img_spdif_out_info,
+		.get = img_spdif_out_get_status_mask
+	},
+	{
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
+		.info = img_spdif_out_info,
+		.get = img_spdif_out_get_status,
+		.put = img_spdif_out_set_status
+	}
+};
+
+static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
+			struct snd_soc_dai *dai)
+{
+	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
+	u32 reg;
+	unsigned long flags;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
+		reg |= IMG_SPDIF_OUT_CTL_SRT_MASK;
+		img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		spin_lock_irqsave(&spdif->lock, flags);
+		img_spdif_out_reset(spdif);
+		spin_unlock_irqrestore(&spdif->lock, flags);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
+{
+	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
+	unsigned int channels;
+	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
+	u32 reg;
+	snd_pcm_format_t format;
+
+	rate = params_rate(params);
+	format = params_format(params);
+	channels = params_channels(params);
+
+	dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
+			rate, channels, format);
+
+	if (format != SNDRV_PCM_FORMAT_S32_LE)
+		return -EINVAL;
+
+	if (channels != 2)
+		return -EINVAL;
+
+	pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
+	if (pre_div_a < 0)
+		return pre_div_a;
+	pre_div_b = clk_round_rate(spdif->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(spdif->clk_ref, pre_div_b);
+	else
+		clk_set_rate(spdif->clk_ref, pre_div_a);
+
+	/*
+	 * Another driver (eg machine driver) may have rejected the above
+	 * change. Get the current rate and set the register bit according to
+	 * the new min diff
+	 */
+	clk_rate = clk_get_rate(spdif->clk_ref);
+
+	diff_a = abs((clk_rate / 256) - rate);
+	diff_b = abs((clk_rate / 384) - rate);
+
+	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
+	if (diff_a <= diff_b)
+		reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
+	else
+		reg |= IMG_SPDIF_OUT_CTL_CLK_MASK;
+	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
+	.trigger = img_spdif_out_trigger,
+	.hw_params = img_spdif_out_hw_params
+};
+
+static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
+{
+	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
+
+	snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
+
+	snd_soc_add_dai_controls(dai, img_spdif_out_controls,
+			ARRAY_SIZE(img_spdif_out_controls));
+
+	return 0;
+}
+
+static struct snd_soc_dai_driver img_spdif_out_dai = {
+	.probe = img_spdif_out_dai_probe,
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_192000,
+		.formats = SNDRV_PCM_FMTBIT_S32_LE
+	},
+	.ops = &img_spdif_out_dai_ops
+};
+
+static const struct snd_soc_component_driver img_spdif_out_component = {
+	.name = "img-spdif-out"
+};
+
+static int img_spdif_out_probe(struct platform_device *pdev)
+{
+	struct img_spdif_out *spdif;
+	struct resource *res;
+	void __iomem *base;
+	int ret;
+	struct device *dev = &pdev->dev;
+
+	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
+	if (!spdif)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, spdif);
+
+	spdif->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);
+
+	spdif->base = base;
+
+	spdif->rst = devm_reset_control_get(&pdev->dev, "rst");
+	if (IS_ERR(spdif->rst)) {
+		if (PTR_ERR(spdif->rst) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "No top level reset found\n");
+		return PTR_ERR(spdif->rst);
+	}
+
+	spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
+	if (IS_ERR(spdif->clk_sys)) {
+		if (PTR_ERR(spdif->clk_sys) != -EPROBE_DEFER)
+			dev_err(dev, "Failed to acquire clock 'sys'\n");
+		return PTR_ERR(spdif->clk_sys);
+	}
+
+	spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
+	if (IS_ERR(spdif->clk_ref)) {
+		if (PTR_ERR(spdif->clk_ref) != -EPROBE_DEFER)
+			dev_err(dev, "Failed to acquire clock 'ref'\n");
+		return PTR_ERR(spdif->clk_ref);
+	}
+
+	ret = clk_prepare_enable(spdif->clk_sys);
+	if (ret)
+		return ret;
+
+	img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
+				IMG_SPDIF_OUT_CTL);
+
+	img_spdif_out_reset(spdif);
+
+	pm_runtime_enable(&pdev->dev);
+	if (!pm_runtime_enabled(&pdev->dev)) {
+		ret = img_spdif_out_resume(&pdev->dev);
+		if (ret)
+			goto err_pm_disable;
+	}
+
+	spin_lock_init(&spdif->lock);
+
+	spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
+	spdif->dma_data.addr_width = 4;
+	spdif->dma_data.maxburst = 4;
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+			&img_spdif_out_component,
+			&img_spdif_out_dai, 1);
+	if (ret)
+		goto err_suspend;
+
+	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
+	if (ret)
+		goto err_suspend;
+
+	dev_dbg(&pdev->dev, "Probe successful\n");
+
+	return 0;
+
+err_suspend:
+	if (!pm_runtime_status_suspended(&pdev->dev))
+		img_spdif_out_suspend(&pdev->dev);
+err_pm_disable:
+	pm_runtime_disable(&pdev->dev);
+	clk_disable_unprepare(spdif->clk_sys);
+
+	return ret;
+}
+
+static int img_spdif_out_dev_remove(struct platform_device *pdev)
+{
+	struct img_spdif_out *spdif = platform_get_drvdata(pdev);
+
+	pm_runtime_disable(&pdev->dev);
+	if (!pm_runtime_status_suspended(&pdev->dev))
+		img_spdif_out_suspend(&pdev->dev);
+
+	clk_disable_unprepare(spdif->clk_sys);
+
+	return 0;
+}
+
+static const struct of_device_id img_spdif_out_of_match[] = {
+	{ .compatible = "img,spdif-out" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);
+
+static const struct dev_pm_ops img_spdif_out_pm_ops = {
+	SET_RUNTIME_PM_OPS(img_spdif_out_suspend,
+			   img_spdif_out_resume, NULL)
+};
+
+static struct platform_driver img_spdif_out_driver = {
+	.driver = {
+		.name = "img-spdif-out",
+		.of_match_table = img_spdif_out_of_match,
+		.pm = &img_spdif_out_pm_ops
+	},
+	.probe = img_spdif_out_probe,
+	.remove = img_spdif_out_dev_remove
+};
+module_platform_driver(img_spdif_out_driver);
+
+MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
+MODULE_DESCRIPTION("IMG SPDIF Output driver");
+MODULE_LICENSE("GPL v2");