ASoC: Add TXx9 AC link controller driver (v3)

This patch adds support for the integrated ACLC of the TXx9 family.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/txx9/txx9aclc-ac97.c b/sound/soc/txx9/txx9aclc-ac97.c
new file mode 100644
index 0000000..0f83bdb
--- /dev/null
+++ b/sound/soc/txx9/txx9aclc-ac97.c
@@ -0,0 +1,255 @@
+/*
+ * TXx9 ACLC AC97 driver
+ *
+ * Copyright (C) 2009 Atsushi Nemoto
+ *
+ * Based on RBTX49xx patch from CELF patch archive.
+ * (C) Copyright TOSHIBA CORPORATION 2004-2006
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/soc.h>
+#include "txx9aclc.h"
+
+#define AC97_DIR	\
+	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
+
+#define AC97_RATES	\
+	SNDRV_PCM_RATE_8000_48000
+
+#ifdef __BIG_ENDIAN
+#define AC97_FMTS	SNDRV_PCM_FMTBIT_S16_BE
+#else
+#define AC97_FMTS	SNDRV_PCM_FMTBIT_S16_LE
+#endif
+
+static DECLARE_WAIT_QUEUE_HEAD(ac97_waitq);
+
+/* REVISIT: How to find txx9aclc_soc_device from snd_ac97? */
+static struct txx9aclc_soc_device *txx9aclc_soc_dev;
+
+static int txx9aclc_regready(struct txx9aclc_soc_device *dev)
+{
+	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_get_plat_drvdata(dev);
+
+	return __raw_readl(drvdata->base + ACINTSTS) & ACINT_REGACCRDY;
+}
+
+/* AC97 controller reads codec register */
+static unsigned short txx9aclc_ac97_read(struct snd_ac97 *ac97,
+					 unsigned short reg)
+{
+	struct txx9aclc_soc_device *dev = txx9aclc_soc_dev;
+	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_get_plat_drvdata(dev);
+	void __iomem *base = drvdata->base;
+	u32 dat;
+
+	if (!(__raw_readl(base + ACINTSTS) & ACINT_CODECRDY(ac97->num)))
+		return 0xffff;
+	reg |= ac97->num << 7;
+	dat = (reg << ACREGACC_REG_SHIFT) | ACREGACC_READ;
+	__raw_writel(dat, base + ACREGACC);
+	__raw_writel(ACINT_REGACCRDY, base + ACINTEN);
+	if (!wait_event_timeout(ac97_waitq, txx9aclc_regready(dev), HZ)) {
+		__raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
+		dev_err(dev->soc_dev.dev, "ac97 read timeout (reg %#x)\n", reg);
+		dat = 0xffff;
+		goto done;
+	}
+	dat = __raw_readl(base + ACREGACC);
+	if (((dat >> ACREGACC_REG_SHIFT) & 0xff) != reg) {
+		dev_err(dev->soc_dev.dev, "reg mismatch %x with %x\n",
+			dat, reg);
+		dat = 0xffff;
+		goto done;
+	}
+	dat = (dat >> ACREGACC_DAT_SHIFT) & 0xffff;
+done:
+	__raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
+	return dat;
+}
+
+/* AC97 controller writes to codec register */
+static void txx9aclc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
+				unsigned short val)
+{
+	struct txx9aclc_soc_device *dev = txx9aclc_soc_dev;
+	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_get_plat_drvdata(dev);
+	void __iomem *base = drvdata->base;
+
+	__raw_writel(((reg | (ac97->num << 7)) << ACREGACC_REG_SHIFT) |
+		     (val << ACREGACC_DAT_SHIFT),
+		     base + ACREGACC);
+	__raw_writel(ACINT_REGACCRDY, base + ACINTEN);
+	if (!wait_event_timeout(ac97_waitq, txx9aclc_regready(dev), HZ)) {
+		dev_err(dev->soc_dev.dev,
+			"ac97 write timeout (reg %#x)\n", reg);
+	}
+	__raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
+}
+
+static void txx9aclc_ac97_cold_reset(struct snd_ac97 *ac97)
+{
+	struct txx9aclc_soc_device *dev = txx9aclc_soc_dev;
+	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_get_plat_drvdata(dev);
+	void __iomem *base = drvdata->base;
+	u32 ready = ACINT_CODECRDY(ac97->num) | ACINT_REGACCRDY;
+
+	__raw_writel(ACCTL_ENLINK, base + ACCTLDIS);
+	mmiowb();
+	udelay(1);
+	__raw_writel(ACCTL_ENLINK, base + ACCTLEN);
+	/* wait for primary codec ready status */
+	__raw_writel(ready, base + ACINTEN);
+	if (!wait_event_timeout(ac97_waitq,
+				(__raw_readl(base + ACINTSTS) & ready) == ready,
+				HZ)) {
+		dev_err(&ac97->dev, "primary codec is not ready "
+			"(status %#x)\n",
+			__raw_readl(base + ACINTSTS));
+	}
+	__raw_writel(ACINT_REGACCRDY, base + ACINTSTS);
+	__raw_writel(ready, base + ACINTDIS);
+}
+
+/* AC97 controller operations */
+struct snd_ac97_bus_ops soc_ac97_ops = {
+	.read		= txx9aclc_ac97_read,
+	.write		= txx9aclc_ac97_write,
+	.reset		= txx9aclc_ac97_cold_reset,
+};
+EXPORT_SYMBOL_GPL(soc_ac97_ops);
+
+static irqreturn_t txx9aclc_ac97_irq(int irq, void *dev_id)
+{
+	struct txx9aclc_plat_drvdata *drvdata = dev_id;
+	void __iomem *base = drvdata->base;
+
+	__raw_writel(__raw_readl(base + ACINTMSTS), base + ACINTDIS);
+	wake_up(&ac97_waitq);
+	return IRQ_HANDLED;
+}
+
+static int txx9aclc_ac97_probe(struct platform_device *pdev,
+			       struct snd_soc_dai *dai)
+{
+	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+	struct txx9aclc_soc_device *dev =
+		container_of(socdev, struct txx9aclc_soc_device, soc_dev);
+
+	dev->aclc_pdev = to_platform_device(dai->dev);
+	txx9aclc_soc_dev = dev;
+	return 0;
+}
+
+static void txx9aclc_ac97_remove(struct platform_device *pdev,
+				 struct snd_soc_dai *dai)
+{
+	struct platform_device *aclc_pdev = to_platform_device(dai->dev);
+	struct txx9aclc_plat_drvdata *drvdata = platform_get_drvdata(aclc_pdev);
+
+	/* disable AC-link */
+	__raw_writel(ACCTL_ENLINK, drvdata->base + ACCTLDIS);
+	txx9aclc_soc_dev = NULL;
+}
+
+struct snd_soc_dai txx9aclc_ac97_dai = {
+	.name			= "txx9aclc_ac97",
+	.ac97_control		= 1,
+	.probe			= txx9aclc_ac97_probe,
+	.remove			= txx9aclc_ac97_remove,
+	.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,
+	},
+};
+EXPORT_SYMBOL_GPL(txx9aclc_ac97_dai);
+
+static int __devinit txx9aclc_ac97_dev_probe(struct platform_device *pdev)
+{
+	struct txx9aclc_plat_drvdata *drvdata;
+	struct resource *r;
+	int err;
+	int irq;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r)
+		return -EBUSY;
+
+	if (!devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
+				     dev_name(&pdev->dev)))
+		return -EBUSY;
+
+	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, drvdata);
+	drvdata->physbase = r->start;
+	if (sizeof(drvdata->physbase) > sizeof(r->start) &&
+	    r->start >= TXX9_DIRECTMAP_BASE &&
+	    r->start < TXX9_DIRECTMAP_BASE + 0x400000)
+		drvdata->physbase |= 0xf00000000ull;
+	drvdata->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+	if (!drvdata->base)
+		return -EBUSY;
+	err = devm_request_irq(&pdev->dev, irq, txx9aclc_ac97_irq,
+			       IRQF_DISABLED, dev_name(&pdev->dev), drvdata);
+	if (err < 0)
+		return err;
+
+	txx9aclc_ac97_dai.dev = &pdev->dev;
+	return snd_soc_register_dai(&txx9aclc_ac97_dai);
+}
+
+static int __devexit txx9aclc_ac97_dev_remove(struct platform_device *pdev)
+{
+	snd_soc_unregister_dai(&txx9aclc_ac97_dai);
+	return 0;
+}
+
+static struct platform_driver txx9aclc_ac97_driver = {
+	.probe		= txx9aclc_ac97_dev_probe,
+	.remove		= __devexit_p(txx9aclc_ac97_dev_remove),
+	.driver		= {
+		.name	= "txx9aclc-ac97",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init txx9aclc_ac97_init(void)
+{
+	return platform_driver_register(&txx9aclc_ac97_driver);
+}
+
+static void __exit txx9aclc_ac97_exit(void)
+{
+	platform_driver_unregister(&txx9aclc_ac97_driver);
+}
+
+module_init(txx9aclc_ac97_init);
+module_exit(txx9aclc_ac97_exit);
+
+MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
+MODULE_DESCRIPTION("TXx9 ACLC AC97 driver");
+MODULE_LICENSE("GPL");