ASoC: Alchemy AC97C/I2SC audio support

This patch adds ASoC support for the AC97 and I2S controllers
on the old Au1000/Au1500/Au1100 chips,

AC97 Tested on a Db1500.  I2S untested since none of the boards
actually have an I2S codec wired up (just test pins).

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/au1x/i2sc.c b/sound/soc/au1x/i2sc.c
new file mode 100644
index 0000000..b4172fd
--- /dev/null
+++ b/sound/soc/au1x/i2sc.c
@@ -0,0 +1,347 @@
+/*
+ * Au1000/Au1500/Au1100 I2S controller driver for ASoC
+ *
+ * (c) 2011 Manuel Lauss <manuel.lauss@googlemail.com>
+ *
+ * Note: clock supplied to the I2S controller must be 256x samplerate.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <asm/mach-au1x00/au1000.h>
+
+#include "psc.h"
+
+#define I2S_RXTX	0x00
+#define I2S_CFG		0x04
+#define I2S_ENABLE	0x08
+
+#define CFG_XU		(1 << 25)	/* tx underflow */
+#define CFG_XO		(1 << 24)
+#define CFG_RU		(1 << 23)
+#define CFG_RO		(1 << 22)
+#define CFG_TR		(1 << 21)
+#define CFG_TE		(1 << 20)
+#define CFG_TF		(1 << 19)
+#define CFG_RR		(1 << 18)
+#define CFG_RF		(1 << 17)
+#define CFG_ICK		(1 << 12)	/* clock invert */
+#define CFG_PD		(1 << 11)	/* set to make I2SDIO INPUT */
+#define CFG_LB		(1 << 10)	/* loopback */
+#define CFG_IC		(1 << 9)	/* word select invert */
+#define CFG_FM_I2S	(0 << 7)	/* I2S format */
+#define CFG_FM_LJ	(1 << 7)	/* left-justified */
+#define CFG_FM_RJ	(2 << 7)	/* right-justified */
+#define CFG_FM_MASK	(3 << 7)
+#define CFG_TN		(1 << 6)	/* tx fifo en */
+#define CFG_RN		(1 << 5)	/* rx fifo en */
+#define CFG_SZ_8	(0x08)
+#define CFG_SZ_16	(0x10)
+#define CFG_SZ_18	(0x12)
+#define CFG_SZ_20	(0x14)
+#define CFG_SZ_24	(0x18)
+#define CFG_SZ_MASK	(0x1f)
+#define EN_D		(1 << 1)	/* DISable */
+#define EN_CE		(1 << 0)	/* clock enable */
+
+/* only limited by clock generator and board design */
+#define AU1XI2SC_RATES \
+	SNDRV_PCM_RATE_CONTINUOUS
+
+#define AU1XI2SC_FMTS \
+	(SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_U8 |		\
+	SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |	\
+	SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |	\
+	SNDRV_PCM_FMTBIT_S18_3LE | SNDRV_PCM_FMTBIT_U18_3LE |	\
+	SNDRV_PCM_FMTBIT_S18_3BE | SNDRV_PCM_FMTBIT_U18_3BE |	\
+	SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_U20_3LE |	\
+	SNDRV_PCM_FMTBIT_S20_3BE | SNDRV_PCM_FMTBIT_U20_3BE |	\
+	SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE |	\
+	SNDRV_PCM_FMTBIT_U24_LE | SNDRV_PCM_FMTBIT_U24_BE |	\
+	0)
+
+static inline unsigned long RD(struct au1xpsc_audio_data *ctx, int reg)
+{
+	return __raw_readl(ctx->mmio + reg);
+}
+
+static inline void WR(struct au1xpsc_audio_data *ctx, int reg, unsigned long v)
+{
+	__raw_writel(v, ctx->mmio + reg);
+	wmb();
+}
+
+static int au1xi2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
+{
+	struct au1xpsc_audio_data *ctx = snd_soc_dai_get_drvdata(cpu_dai);
+	unsigned long c;
+	int ret;
+
+	ret = -EINVAL;
+	c = ctx->cfg;
+
+	c &= ~CFG_FM_MASK;
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		c |= CFG_FM_I2S;
+		break;
+	case SND_SOC_DAIFMT_MSB:
+		c |= CFG_FM_RJ;
+		break;
+	case SND_SOC_DAIFMT_LSB:
+		c |= CFG_FM_LJ;
+		break;
+	default:
+		goto out;
+	}
+
+	c &= ~(CFG_IC | CFG_ICK);		/* IB-IF */
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		c |= CFG_IC | CFG_ICK;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		c |= CFG_IC;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		c |= CFG_ICK;
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		break;
+	default:
+		goto out;
+	}
+
+	/* I2S controller only supports master */
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBS_CFS:	/* CODEC slave */
+		break;
+	default:
+		goto out;
+	}
+
+	ret = 0;
+	ctx->cfg = c;
+out:
+	return ret;
+}
+
+static int au1xi2s_trigger(struct snd_pcm_substream *substream,
+			   int cmd, struct snd_soc_dai *dai)
+{
+	struct au1xpsc_audio_data *ctx = snd_soc_dai_get_drvdata(dai);
+	int stype = SUBSTREAM_TYPE(substream);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		/* power up */
+		WR(ctx, I2S_ENABLE, EN_D | EN_CE);
+		WR(ctx, I2S_ENABLE, EN_CE);
+		ctx->cfg |= (stype == PCM_TX) ? CFG_TN : CFG_RN;
+		WR(ctx, I2S_CFG, ctx->cfg);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		ctx->cfg &= ~((stype == PCM_TX) ? CFG_TN : CFG_RN);
+		WR(ctx, I2S_CFG, ctx->cfg);
+		WR(ctx, I2S_ENABLE, EN_D);		/* power off */
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static unsigned long msbits_to_reg(int msbits)
+{
+	switch (msbits) {
+	case 8:
+		return CFG_SZ_8;
+	case 16:
+		return CFG_SZ_16;
+	case 18:
+		return CFG_SZ_18;
+	case 20:
+		return CFG_SZ_20;
+	case 24:
+		return CFG_SZ_24;
+	}
+	return 0;
+}
+
+static int au1xi2s_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *dai)
+{
+	struct au1xpsc_audio_data *ctx = snd_soc_dai_get_drvdata(dai);
+	unsigned long v;
+
+	v = msbits_to_reg(params->msbits);
+	if (!v)
+		return -EINVAL;
+
+	ctx->cfg &= ~CFG_SZ_MASK;
+	ctx->cfg |= v;
+	return 0;
+}
+
+static int au1xi2s_startup(struct snd_pcm_substream *substream,
+			   struct snd_soc_dai *dai)
+{
+	struct au1xpsc_audio_data *ctx = snd_soc_dai_get_drvdata(dai);
+	snd_soc_dai_set_dma_data(dai, substream, &ctx->dmaids[0]);
+	return 0;
+}
+
+static const struct snd_soc_dai_ops au1xi2s_dai_ops = {
+	.startup	= au1xi2s_startup,
+	.trigger	= au1xi2s_trigger,
+	.hw_params	= au1xi2s_hw_params,
+	.set_fmt	= au1xi2s_set_fmt,
+};
+
+static struct snd_soc_dai_driver au1xi2s_dai_driver = {
+	.symmetric_rates	= 1,
+	.playback = {
+		.rates		= AU1XI2SC_RATES,
+		.formats	= AU1XI2SC_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 2,
+	},
+	.capture = {
+		.rates		= AU1XI2SC_RATES,
+		.formats	= AU1XI2SC_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 2,
+	},
+	.ops = &au1xi2s_dai_ops,
+};
+
+static int __devinit au1xi2s_drvprobe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *r;
+	struct au1xpsc_audio_data *ctx;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		ret = -ENODEV;
+		goto out0;
+	}
+
+	ret = -EBUSY;
+	if (!request_mem_region(r->start, resource_size(r), pdev->name))
+		goto out0;
+
+	ctx->mmio = ioremap_nocache(r->start, resource_size(r));
+	if (!ctx->mmio)
+		goto out1;
+
+	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	if (!r)
+		goto out1;
+	ctx->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = r->start;
+
+	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+	if (!r)
+		goto out1;
+	ctx->dmaids[SNDRV_PCM_STREAM_CAPTURE] = r->start;
+
+	platform_set_drvdata(pdev, ctx);
+
+	ret = snd_soc_register_dai(&pdev->dev, &au1xi2s_dai_driver);
+	if (ret)
+		goto out1;
+
+	return 0;
+
+	snd_soc_unregister_dai(&pdev->dev);
+out1:
+	release_mem_region(r->start, resource_size(r));
+out0:
+	kfree(ctx);
+	return ret;
+}
+
+static int __devexit au1xi2s_drvremove(struct platform_device *pdev)
+{
+	struct au1xpsc_audio_data *ctx = platform_get_drvdata(pdev);
+	struct resource *r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	snd_soc_unregister_dai(&pdev->dev);
+
+	WR(ctx, I2S_ENABLE, EN_D);	/* clock off, disable */
+
+	iounmap(ctx->mmio);
+	release_mem_region(r->start, resource_size(r));
+	kfree(ctx);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int au1xi2s_drvsuspend(struct device *dev)
+{
+	struct au1xpsc_audio_data *ctx = dev_get_drvdata(dev);
+
+	WR(ctx, I2S_ENABLE, EN_D);	/* clock off, disable */
+
+	return 0;
+}
+
+static int au1xi2s_drvresume(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops au1xi2sc_pmops = {
+	.suspend	= au1xi2s_drvsuspend,
+	.resume		= au1xi2s_drvresume,
+};
+
+#define AU1XI2SC_PMOPS (&au1xi2sc_pmops)
+
+#else
+
+#define AU1XI2SC_PMOPS NULL
+
+#endif
+
+static struct platform_driver au1xi2s_driver = {
+	.driver	= {
+		.name	= "alchemy-i2sc",
+		.owner	= THIS_MODULE,
+		.pm	= AU1XI2SC_PMOPS,
+	},
+	.probe		= au1xi2s_drvprobe,
+	.remove		= __devexit_p(au1xi2s_drvremove),
+};
+
+static int __init au1xi2s_load(void)
+{
+	return platform_driver_register(&au1xi2s_driver);
+}
+
+static void __exit au1xi2s_unload(void)
+{
+	platform_driver_unregister(&au1xi2s_driver);
+}
+
+module_init(au1xi2s_load);
+module_exit(au1xi2s_unload);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au1000/1500/1100 I2S ASoC driver");
+MODULE_AUTHOR("Manuel Lauss");