ALSA: ASoC: Au12x0/Au1550 PSC Audio support

Audio for Au12x0/Au1550 PSCs in AC97 and I2S mode, for ASoC v1 framework.

- DBDMA, AC97 and I2S drivers
- sample AC97 machine code (Db1200)

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/sound/soc/au1x/psc-i2s.c b/sound/soc/au1x/psc-i2s.c
new file mode 100644
index 0000000..ba4b5c1
--- /dev/null
+++ b/sound/soc/au1x/psc-i2s.c
@@ -0,0 +1,414 @@
+/*
+ * Au12x0/Au1550 PSC ALSA ASoC audio support.
+ *
+ * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
+ *	Manuel Lauss <mano@roarinelk.homelinux.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Au1xxx-PSC I2S glue.
+ *
+ * NOTE: all of these drivers can only work with a SINGLE instance
+ *	 of a PSC. Multiple independent audio devices are impossible
+ *	 with ASoC v1.
+ * NOTE: so far only PSC slave mode (bit- and frameclock) is supported.
+ */
+
+#include <linux/init.h>
+#include <linux/module.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 <asm/mach-au1x00/au1xxx_psc.h>
+
+#include "psc.h"
+
+/* supported I2S DAI hardware formats */
+#define AU1XPSC_I2S_DAIFMT \
+	(SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_LEFT_J |	\
+	 SND_SOC_DAIFMT_NB_NF)
+
+/* supported I2S direction */
+#define AU1XPSC_I2S_DIR \
+	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
+
+#define AU1XPSC_I2S_RATES \
+	SNDRV_PCM_RATE_8000_192000
+
+#define AU1XPSC_I2S_FMTS \
+	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
+
+#define I2SSTAT_BUSY(stype)	\
+	((stype) == PCM_TX ? PSC_I2SSTAT_TB : PSC_I2SSTAT_RB)
+#define I2SPCR_START(stype)	\
+	((stype) == PCM_TX ? PSC_I2SPCR_TS : PSC_I2SPCR_RS)
+#define I2SPCR_STOP(stype)	\
+	((stype) == PCM_TX ? PSC_I2SPCR_TP : PSC_I2SPCR_RP)
+#define I2SPCR_CLRFIFO(stype)	\
+	((stype) == PCM_TX ? PSC_I2SPCR_TC : PSC_I2SPCR_RC)
+
+
+/* instance data. There can be only one, MacLeod!!!! */
+static struct au1xpsc_audio_data *au1xpsc_i2s_workdata;
+
+static int au1xpsc_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
+			       unsigned int fmt)
+{
+	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
+	unsigned long ct;
+	int ret;
+
+	ret = -EINVAL;
+
+	ct = pscdata->cfg;
+
+	ct &= ~(PSC_I2SCFG_XM | PSC_I2SCFG_MLJ);	/* left-justified */
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		ct |= PSC_I2SCFG_XM;	/* enable I2S mode */
+		break;
+	case SND_SOC_DAIFMT_MSB:
+		break;
+	case SND_SOC_DAIFMT_LSB:
+		ct |= PSC_I2SCFG_MLJ;	/* LSB (right-) justified */
+		break;
+	default:
+		goto out;
+	}
+
+	ct &= ~(PSC_I2SCFG_BI | PSC_I2SCFG_WI);		/* IB-IF */
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		ct |= PSC_I2SCFG_BI | PSC_I2SCFG_WI;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		ct |= PSC_I2SCFG_BI;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		ct |= PSC_I2SCFG_WI;
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		break;
+	default:
+		goto out;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:	/* CODEC master */
+		ct |= PSC_I2SCFG_MS;	/* PSC I2S slave mode */
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:	/* CODEC slave */
+		ct &= ~PSC_I2SCFG_MS;	/* PSC I2S Master mode */
+		break;
+	default:
+		goto out;
+	}
+
+	pscdata->cfg = ct;
+	ret = 0;
+out:
+	return ret;
+}
+
+static int au1xpsc_i2s_hw_params(struct snd_pcm_substream *substream,
+				 struct snd_pcm_hw_params *params)
+{
+	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
+
+	int cfgbits;
+	unsigned long stat;
+
+	/* check if the PSC is already streaming data */
+	stat = au_readl(I2S_STAT(pscdata));
+	if (stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB)) {
+		/* reject parameters not currently set up in hardware */
+		cfgbits = au_readl(I2S_CFG(pscdata));
+		if ((PSC_I2SCFG_GET_LEN(cfgbits) != params->msbits) ||
+		    (params_rate(params) != pscdata->rate))
+			return -EINVAL;
+	} else {
+		/* set sample bitdepth */
+		pscdata->cfg &= ~(0x1f << 4);
+		pscdata->cfg |= PSC_I2SCFG_SET_LEN(params->msbits);
+		/* remember current rate for other stream */
+		pscdata->rate = params_rate(params);
+	}
+	return 0;
+}
+
+/* Configure PSC late:  on my devel systems the codec  is I2S master and
+ * supplies the i2sbitclock __AND__ i2sMclk (!) to the PSC unit.  ASoC
+ * uses aggressive PM and  switches the codec off  when it is not in use
+ * which also means the PSC unit doesn't get any clocks and is therefore
+ * dead. That's why this chunk here gets called from the trigger callback
+ * because I can be reasonably certain the codec is driving the clocks.
+ */
+static int au1xpsc_i2s_configure(struct au1xpsc_audio_data *pscdata)
+{
+	unsigned long tmo;
+
+	/* bring PSC out of sleep, and configure I2S unit */
+	au_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
+	au_sync();
+
+	tmo = 1000000;
+	while (!(au_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_SR) && tmo)
+		tmo--;
+
+	if (!tmo)
+		goto psc_err;
+
+	au_writel(0, I2S_CFG(pscdata));
+	au_sync();
+	au_writel(pscdata->cfg | PSC_I2SCFG_DE_ENABLE, I2S_CFG(pscdata));
+	au_sync();
+
+	/* wait for I2S controller to become ready */
+	tmo = 1000000;
+	while (!(au_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_DR) && tmo)
+		tmo--;
+
+	if (tmo)
+		return 0;
+
+psc_err:
+	au_writel(0, I2S_CFG(pscdata));
+	au_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
+	au_sync();
+	return -ETIMEDOUT;
+}
+
+static int au1xpsc_i2s_start(struct au1xpsc_audio_data *pscdata, int stype)
+{
+	unsigned long tmo, stat;
+	int ret;
+
+	ret = 0;
+
+	/* if both TX and RX are idle, configure the PSC  */
+	stat = au_readl(I2S_STAT(pscdata));
+	if (!(stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB))) {
+		ret = au1xpsc_i2s_configure(pscdata);
+		if (ret)
+			goto out;
+	}
+
+	au_writel(I2SPCR_CLRFIFO(stype), I2S_PCR(pscdata));
+	au_sync();
+	au_writel(I2SPCR_START(stype), I2S_PCR(pscdata));
+	au_sync();
+
+	/* wait for start confirmation */
+	tmo = 1000000;
+	while (!(au_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
+		tmo--;
+
+	if (!tmo) {
+		au_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
+		au_sync();
+		ret = -ETIMEDOUT;
+	}
+out:
+	return ret;
+}
+
+static int au1xpsc_i2s_stop(struct au1xpsc_audio_data *pscdata, int stype)
+{
+	unsigned long tmo, stat;
+
+	au_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
+	au_sync();
+
+	/* wait for stop confirmation */
+	tmo = 1000000;
+	while ((au_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
+		tmo--;
+
+	/* if both TX and RX are idle, disable PSC */
+	stat = au_readl(I2S_STAT(pscdata));
+	if (!(stat & (PSC_I2SSTAT_RB | PSC_I2SSTAT_RB))) {
+		au_writel(0, I2S_CFG(pscdata));
+		au_sync();
+		au_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
+		au_sync();
+	}
+	return 0;
+}
+
+static int au1xpsc_i2s_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
+	int ret, stype = SUBSTREAM_TYPE(substream);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		ret = au1xpsc_i2s_start(pscdata, stype);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		ret = au1xpsc_i2s_stop(pscdata, stype);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+	return ret;
+}
+
+static int au1xpsc_i2s_probe(struct platform_device *pdev,
+			     struct snd_soc_dai *dai)
+{
+	struct resource *r;
+	unsigned long sel;
+	int ret;
+
+	if (au1xpsc_i2s_workdata)
+		return -EBUSY;
+
+	au1xpsc_i2s_workdata =
+		kzalloc(sizeof(struct au1xpsc_audio_data), GFP_KERNEL);
+	if (!au1xpsc_i2s_workdata)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		ret = -ENODEV;
+		goto out0;
+	}
+
+	ret = -EBUSY;
+	au1xpsc_i2s_workdata->ioarea =
+		request_mem_region(r->start, r->end - r->start + 1,
+					"au1xpsc_i2s");
+	if (!au1xpsc_i2s_workdata->ioarea)
+		goto out0;
+
+	au1xpsc_i2s_workdata->mmio = ioremap(r->start, 0xffff);
+	if (!au1xpsc_i2s_workdata->mmio)
+		goto out1;
+
+	/* preserve PSC clock source set up by platform (dev.platform_data
+	 * is already occupied by soc layer)
+	 */
+	sel = au_readl(PSC_SEL(au1xpsc_i2s_workdata)) & PSC_SEL_CLK_MASK;
+	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
+	au_sync();
+	au_writel(PSC_SEL_PS_I2SMODE | sel, PSC_SEL(au1xpsc_i2s_workdata));
+	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
+	au_sync();
+
+	/* preconfigure: set max rx/tx fifo depths */
+	au1xpsc_i2s_workdata->cfg |=
+			PSC_I2SCFG_RT_FIFO8 | PSC_I2SCFG_TT_FIFO8;
+
+	/* don't wait for I2S core to become ready now; clocks may not
+	 * be running yet; depending on clock input for PSC a wait might
+	 * time out.
+	 */
+
+	return 0;
+
+out1:
+	release_resource(au1xpsc_i2s_workdata->ioarea);
+	kfree(au1xpsc_i2s_workdata->ioarea);
+out0:
+	kfree(au1xpsc_i2s_workdata);
+	au1xpsc_i2s_workdata = NULL;
+	return ret;
+}
+
+static void au1xpsc_i2s_remove(struct platform_device *pdev,
+			       struct snd_soc_dai *dai)
+{
+	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
+	au_sync();
+	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
+	au_sync();
+
+	iounmap(au1xpsc_i2s_workdata->mmio);
+	release_resource(au1xpsc_i2s_workdata->ioarea);
+	kfree(au1xpsc_i2s_workdata->ioarea);
+	kfree(au1xpsc_i2s_workdata);
+	au1xpsc_i2s_workdata = NULL;
+}
+
+static int au1xpsc_i2s_suspend(struct platform_device *pdev,
+			       struct snd_soc_dai *cpu_dai)
+{
+	/* save interesting register and disable PSC */
+	au1xpsc_i2s_workdata->pm[0] =
+		au_readl(PSC_SEL(au1xpsc_i2s_workdata));
+
+	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
+	au_sync();
+	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
+	au_sync();
+
+	return 0;
+}
+
+static int au1xpsc_i2s_resume(struct platform_device *pdev,
+			      struct snd_soc_dai *cpu_dai)
+{
+	/* select I2S mode and PSC clock */
+	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
+	au_sync();
+	au_writel(0, PSC_SEL(au1xpsc_i2s_workdata));
+	au_sync();
+	au_writel(au1xpsc_i2s_workdata->pm[0],
+			PSC_SEL(au1xpsc_i2s_workdata));
+	au_sync();
+
+	return 0;
+}
+
+struct snd_soc_dai au1xpsc_i2s_dai = {
+	.name			= "au1xpsc_i2s",
+	.type			= SND_SOC_DAI_I2S,
+	.probe			= au1xpsc_i2s_probe,
+	.remove			= au1xpsc_i2s_remove,
+	.suspend		= au1xpsc_i2s_suspend,
+	.resume			= au1xpsc_i2s_resume,
+	.playback = {
+		.rates		= AU1XPSC_I2S_RATES,
+		.formats	= AU1XPSC_I2S_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 8,	/* 2 without external help */
+	},
+	.capture = {
+		.rates		= AU1XPSC_I2S_RATES,
+		.formats	= AU1XPSC_I2S_FMTS,
+		.channels_min	= 2,
+		.channels_max	= 8,	/* 2 without external help */
+	},
+	.ops = {
+		.trigger	= au1xpsc_i2s_trigger,
+		.hw_params	= au1xpsc_i2s_hw_params,
+	},
+	.dai_ops = {
+		.set_fmt	= au1xpsc_i2s_set_fmt,
+	},
+};
+EXPORT_SYMBOL(au1xpsc_i2s_dai);
+
+static int __init au1xpsc_i2s_init(void)
+{
+	au1xpsc_i2s_workdata = NULL;
+	return 0;
+}
+
+static void __exit au1xpsc_i2s_exit(void)
+{
+}
+
+module_init(au1xpsc_i2s_init);
+module_exit(au1xpsc_i2s_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Au12x0/Au1550 PSC I2S ALSA ASoC audio driver");
+MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");