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>

1 files changed, 365 insertions, 0 deletions

diff --git a/sound/soc/au1x/ac97c.c b/sound/soc/au1x/ac97c.c
new file mode 100644
index 000000000000..9c05f381d95e
--- /dev/null
+++ b/sound/soc/au1x/ac97c.c
@@ -0,0 +1,365 @@
+/*
+ * Au1000/Au1500/Au1100 AC97C controller driver for ASoC
+ *
+ * (c) 2011 Manuel Lauss <manuel.lauss@googlemail.com>
+ *
+ * based on the old ALSA driver originally written by
+ *			Charles Eidsness <charles@cooper-street.com>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.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"
+
+/* register offsets and bits */
+#define AC97_CONFIG	0x00
+#define AC97_STATUS	0x04
+#define AC97_DATA	0x08
+#define AC97_CMDRESP	0x0c
+#define AC97_ENABLE	0x10
+
+#define CFG_RC(x)	(((x) & 0x3ff) << 13)	/* valid rx slots mask */
+#define CFG_XS(x)	(((x) & 0x3ff) << 3)	/* valid tx slots mask */
+#define CFG_SG		(1 << 2)	/* sync gate */
+#define CFG_SN		(1 << 1)	/* sync control */
+#define CFG_RS		(1 << 0)	/* acrst# control */
+#define STAT_XU		(1 << 11)	/* tx underflow */
+#define STAT_XO		(1 << 10)	/* tx overflow */
+#define STAT_RU		(1 << 9)	/* rx underflow */
+#define STAT_RO		(1 << 8)	/* rx overflow */
+#define STAT_RD		(1 << 7)	/* codec ready */
+#define STAT_CP		(1 << 6)	/* command pending */
+#define STAT_TE		(1 << 4)	/* tx fifo empty */
+#define STAT_TF		(1 << 3)	/* tx fifo full */
+#define STAT_RE		(1 << 1)	/* rx fifo empty */
+#define STAT_RF		(1 << 0)	/* rx fifo full */
+#define CMD_SET_DATA(x)	(((x) & 0xffff) << 16)
+#define CMD_GET_DATA(x)	((x) & 0xffff)
+#define CMD_READ	(1 << 7)
+#define CMD_WRITE	(0 << 7)
+#define CMD_IDX(x)	((x) & 0x7f)
+#define EN_D		(1 << 1)	/* DISable bit */
+#define EN_CE		(1 << 0)	/* clock enable bit */
+
+/* how often to retry failed codec register reads/writes */
+#define AC97_RW_RETRIES	5
+
+#define AC97_RATES	\
+	SNDRV_PCM_RATE_CONTINUOUS
+
+#define AC97_FMTS	\
+	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE)
+
+/* instance data. There can be only one, MacLeod!!!!, fortunately there IS only
+ * once AC97C on early Alchemy chips. The newer ones aren't so lucky.
+ */
+static struct au1xpsc_audio_data *ac97c_workdata;
+#define ac97_to_ctx(x)		ac97c_workdata
+
+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 unsigned short au1xac97c_ac97_read(struct snd_ac97 *ac97,
+					  unsigned short r)
+{
+	struct au1xpsc_audio_data *ctx = ac97_to_ctx(ac97);
+	unsigned int tmo, retry;
+	unsigned long data;
+
+	data = ~0;
+	retry = AC97_RW_RETRIES;
+	do {
+		mutex_lock(&ctx->lock);
+
+		tmo = 5;
+		while ((RD(ctx, AC97_STATUS) & STAT_CP) && tmo--)
+			udelay(21);	/* wait an ac97 frame time */
+		if (!tmo) {
+			pr_debug("ac97rd timeout #1\n");
+			goto next;
+		}
+
+		WR(ctx, AC97_CMDRESP, CMD_IDX(r) | CMD_READ);
+
+		/* stupid errata: data is only valid for 21us, so
+		 * poll, Forrest, poll...
+		 */
+		tmo = 0x10000;
+		while ((RD(ctx, AC97_STATUS) & STAT_CP) && tmo--)
+			asm volatile ("nop");
+		data = RD(ctx, AC97_CMDRESP);
+
+		if (!tmo)
+			pr_debug("ac97rd timeout #2\n");
+
+next:
+		mutex_unlock(&ctx->lock);
+	} while (--retry && !tmo);
+
+	pr_debug("AC97RD %04x %04lx %d\n", r, data, retry);
+
+	return retry ? data & 0xffff : 0xffff;
+}
+
+static void au1xac97c_ac97_write(struct snd_ac97 *ac97, unsigned short r,
+				 unsigned short v)
+{
+	struct au1xpsc_audio_data *ctx = ac97_to_ctx(ac97);
+	unsigned int tmo, retry;
+
+	retry = AC97_RW_RETRIES;
+	do {
+		mutex_lock(&ctx->lock);
+
+		for (tmo = 5; (RD(ctx, AC97_STATUS) & STAT_CP) && tmo; tmo--)
+			udelay(21);
+		if (!tmo) {
+			pr_debug("ac97wr timeout #1\n");
+			goto next;
+		}
+
+		WR(ctx, AC97_CMDRESP, CMD_WRITE | CMD_IDX(r) | CMD_SET_DATA(v));
+
+		for (tmo = 10; (RD(ctx, AC97_STATUS) & STAT_CP) && tmo; tmo--)
+			udelay(21);
+		if (!tmo)
+			pr_debug("ac97wr timeout #2\n");
+next:
+		mutex_unlock(&ctx->lock);
+	} while (--retry && !tmo);
+
+	pr_debug("AC97WR %04x %04x %d\n", r, v, retry);
+}
+
+static void au1xac97c_ac97_warm_reset(struct snd_ac97 *ac97)
+{
+	struct au1xpsc_audio_data *ctx = ac97_to_ctx(ac97);
+
+	WR(ctx, AC97_CONFIG, ctx->cfg | CFG_SG | CFG_SN);
+	msleep(20);
+	WR(ctx, AC97_CONFIG, ctx->cfg | CFG_SG);
+	WR(ctx, AC97_CONFIG, ctx->cfg);
+}
+
+static void au1xac97c_ac97_cold_reset(struct snd_ac97 *ac97)
+{
+	struct au1xpsc_audio_data *ctx = ac97_to_ctx(ac97);
+	int i;
+
+	WR(ctx, AC97_CONFIG, ctx->cfg | CFG_RS);
+	msleep(500);
+	WR(ctx, AC97_CONFIG, ctx->cfg);
+
+	/* wait for codec ready */
+	i = 50;
+	while (((RD(ctx, AC97_STATUS) & STAT_RD) == 0) && --i)
+		msleep(20);
+	if (!i)
+		printk(KERN_ERR "ac97c: codec not ready after cold reset\n");
+}
+
+/* AC97 controller operations */
+struct snd_ac97_bus_ops soc_ac97_ops = {
+	.read		= au1xac97c_ac97_read,
+	.write		= au1xac97c_ac97_write,
+	.reset		= au1xac97c_ac97_cold_reset,
+	.warm_reset	= au1xac97c_ac97_warm_reset,
+};
+EXPORT_SYMBOL_GPL(soc_ac97_ops);	/* globals be gone! */
+
+static int alchemy_ac97c_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 struct snd_soc_dai_ops alchemy_ac97c_ops = {
+	.startup		= alchemy_ac97c_startup,
+};
+
+static int au1xac97c_dai_probe(struct snd_soc_dai *dai)
+{
+	return ac97c_workdata ? 0 : -ENODEV;
+}
+
+static struct snd_soc_dai_driver au1xac97c_dai_driver = {
+	.name			= "alchemy-ac97c",
+	.ac97_control		= 1,
+	.probe			= au1xac97c_dai_probe,
+	.playback = {
+		.rates		= AC97_RATES,
+		.formats	= AC97_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 2,
+	},
+	.capture = {
+		.rates		= AC97_RATES,
+		.formats	= AC97_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 2,
+	},
+	.ops			= &alchemy_ac97c_ops,
+};
+
+static int __devinit au1xac97c_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;
+
+	mutex_init(&ctx->lock);
+
+	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;
+
+	/* switch it on */
+	WR(ctx, AC97_ENABLE, EN_D | EN_CE);
+	WR(ctx, AC97_ENABLE, EN_CE);
+
+	ctx->cfg = CFG_RC(3) | CFG_XS(3);
+	WR(ctx, AC97_CONFIG, ctx->cfg);
+
+	platform_set_drvdata(pdev, ctx);
+
+	ret = snd_soc_register_dai(&pdev->dev, &au1xac97c_dai_driver);
+	if (ret)
+		goto out1;
+
+	ac97c_workdata = ctx;
+	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 au1xac97c_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, AC97_ENABLE, EN_D);	/* clock off, disable */
+
+	iounmap(ctx->mmio);
+	release_mem_region(r->start, resource_size(r));
+	kfree(ctx);
+
+	ac97c_workdata = NULL;	/* MDEV */
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int au1xac97c_drvsuspend(struct device *dev)
+{
+	struct au1xpsc_audio_data *ctx = dev_get_drvdata(dev);
+
+	WR(ctx, AC97_ENABLE, EN_D);	/* clock off, disable */
+
+	return 0;
+}
+
+static int au1xac97c_drvresume(struct device *dev)
+{
+	struct au1xpsc_audio_data *ctx = dev_get_drvdata(dev);
+
+	WR(ctx, AC97_ENABLE, EN_D | EN_CE);
+	WR(ctx, AC97_ENABLE, EN_CE);
+	WR(ctx, AC97_CONFIG, ctx->cfg);
+
+	return 0;
+}
+
+static const struct dev_pm_ops au1xpscac97_pmops = {
+	.suspend	= au1xac97c_drvsuspend,
+	.resume		= au1xac97c_drvresume,
+};
+
+#define AU1XPSCAC97_PMOPS (&au1xpscac97_pmops)
+
+#else
+
+#define AU1XPSCAC97_PMOPS NULL
+
+#endif
+
+static struct platform_driver au1xac97c_driver = {
+	.driver	= {
+		.name	= "alchemy-ac97c",
+		.owner	= THIS_MODULE,
+		.pm	= AU1XPSCAC97_PMOPS,
+	},
+	.probe		= au1xac97c_drvprobe,
+	.remove		= __devexit_p(au1xac97c_drvremove),
+};
+
+static int __init au1xac97c_load(void)
+{
+	ac97c_workdata = NULL;
+	return platform_driver_register(&au1xac97c_driver);
+}
+
+static void __exit au1xac97c_unload(void)
+{
+	platform_driver_unregister(&au1xac97c_driver);
+}
+
+module_init(au1xac97c_load);
+module_exit(au1xac97c_unload);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au1000/1500/1100 AC97C ASoC driver");
+MODULE_AUTHOR("Manuel Lauss");