[ALSA] ASoC Samsung S3C24xx I2S support

This patch by Ben Dooks from Simtec Electronics adds ASoC I2S support
for the Samsung S3C24xx CPU.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Graeme Gregory <gg@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

2 files changed, 474 insertions, 0 deletions

diff --git a/sound/soc/s3c24xx/s3c24xx-i2s.c b/sound/soc/s3c24xx/s3c24xx-i2s.c
new file mode 100644
index 0000000..df655a5
--- /dev/null
+++ b/sound/soc/s3c24xx/s3c24xx-i2s.c
@@ -0,0 +1,439 @@
+/*
+ * s3c24xx-i2s.c  --  ALSA Soc Audio Layer
+ *
+ * (c) 2006 Wolfson Microelectronics PLC.
+ * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
+ *
+ * (c) 2004-2005 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ *
+ *  Revision history
+ *    11th Dec 2006   Merged with Simtec driver
+ *    10th Nov 2006   Initial version.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/arch/regs-iis.h>
+#include <asm/arch/regs-gpio.h>
+#include <asm/arch/regs-clock.h>
+#include <asm/arch/audio.h>
+#include <asm/dma.h>
+#include <asm/arch/dma.h>
+
+#include "s3c24xx-pcm.h"
+#include "s3c24xx-i2s.h"
+
+#define S3C24XX_I2S_DEBUG 0
+#if S3C24XX_I2S_DEBUG
+#define DBG(x...) printk(KERN_DEBUG x)
+#else
+#define DBG(x...)
+#endif
+
+static struct s3c2410_dma_client s3c24xx_dma_client_out = {
+	.name = "I2S PCM Stereo out"
+};
+
+static struct s3c2410_dma_client s3c24xx_dma_client_in = {
+	.name = "I2S PCM Stereo in"
+};
+
+static struct s3c24xx_pcm_dma_params s3c24xx_i2s_pcm_stereo_out = {
+	.client		= &s3c24xx_dma_client_out,
+	.channel	= DMACH_I2S_OUT,
+	.dma_addr	= S3C2410_PA_IIS + S3C2410_IISFIFO
+};
+
+static struct s3c24xx_pcm_dma_params s3c24xx_i2s_pcm_stereo_in = {
+	.client		= &s3c24xx_dma_client_in,
+	.channel	= DMACH_I2S_IN,
+	.dma_addr	= S3C2410_PA_IIS + S3C2410_IISFIFO
+};
+
+struct s3c24xx_i2s_info {
+	void __iomem	*regs;
+	struct clk	*iis_clk;
+};
+static struct s3c24xx_i2s_info s3c24xx_i2s;
+
+static void s3c24xx_snd_txctrl(int on)
+{
+	u32 iisfcon;
+	u32 iiscon;
+	u32 iismod;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	iisfcon = readl(s3c24xx_i2s.regs + S3C2410_IISFCON);
+	iiscon  = readl(s3c24xx_i2s.regs + S3C2410_IISCON);
+	iismod  = readl(s3c24xx_i2s.regs + S3C2410_IISMOD);
+
+	DBG("r: IISCON: %lx IISMOD: %lx IISFCON: %lx\n", iiscon, iismod, iisfcon);
+
+	if (on) {
+		iisfcon |= S3C2410_IISFCON_TXDMA | S3C2410_IISFCON_TXENABLE;
+		iiscon  |= S3C2410_IISCON_TXDMAEN | S3C2410_IISCON_IISEN;
+		iiscon  &= ~S3C2410_IISCON_TXIDLE;
+		iismod  |= S3C2410_IISMOD_TXMODE;
+
+		writel(iismod,  s3c24xx_i2s.regs + S3C2410_IISMOD);
+		writel(iisfcon, s3c24xx_i2s.regs + S3C2410_IISFCON);
+		writel(iiscon,  s3c24xx_i2s.regs + S3C2410_IISCON);
+	} else {
+		/* note, we have to disable the FIFOs otherwise bad things
+		 * seem to happen when the DMA stops. According to the
+		 * Samsung supplied kernel, this should allow the DMA
+		 * engine and FIFOs to reset. If this isn't allowed, the
+		 * DMA engine will simply freeze randomly.
+		 */
+
+		iisfcon &= ~S3C2410_IISFCON_TXENABLE;
+		iisfcon &= ~S3C2410_IISFCON_TXDMA;
+		iiscon  |=  S3C2410_IISCON_TXIDLE;
+		iiscon  &= ~S3C2410_IISCON_TXDMAEN;
+		iismod  &= ~S3C2410_IISMOD_TXMODE;
+
+		writel(iiscon,  s3c24xx_i2s.regs + S3C2410_IISCON);
+		writel(iisfcon, s3c24xx_i2s.regs + S3C2410_IISFCON);
+		writel(iismod,  s3c24xx_i2s.regs + S3C2410_IISMOD);
+	}
+
+	DBG("w: IISCON: %lx IISMOD: %lx IISFCON: %lx\n", iiscon, iismod, iisfcon);
+}
+
+static void s3c24xx_snd_rxctrl(int on)
+{
+	u32 iisfcon;
+	u32 iiscon;
+	u32 iismod;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	iisfcon = readl(s3c24xx_i2s.regs + S3C2410_IISFCON);
+	iiscon  = readl(s3c24xx_i2s.regs + S3C2410_IISCON);
+	iismod  = readl(s3c24xx_i2s.regs + S3C2410_IISMOD);
+
+	DBG("r: IISCON: %lx IISMOD: %lx IISFCON: %lx\n", iiscon, iismod, iisfcon);
+
+	if (on) {
+		iisfcon |= S3C2410_IISFCON_RXDMA | S3C2410_IISFCON_RXENABLE;
+		iiscon  |= S3C2410_IISCON_RXDMAEN | S3C2410_IISCON_IISEN;
+		iiscon  &= ~S3C2410_IISCON_RXIDLE;
+		iismod  |= S3C2410_IISMOD_RXMODE;
+
+		writel(iismod,  s3c24xx_i2s.regs + S3C2410_IISMOD);
+		writel(iisfcon, s3c24xx_i2s.regs + S3C2410_IISFCON);
+		writel(iiscon,  s3c24xx_i2s.regs + S3C2410_IISCON);
+	} else {
+		/* note, we have to disable the FIFOs otherwise bad things
+		 * seem to happen when the DMA stops. According to the
+		 * Samsung supplied kernel, this should allow the DMA
+		 * engine and FIFOs to reset. If this isn't allowed, the
+		 * DMA engine will simply freeze randomly.
+		 */
+
+        iisfcon &= ~S3C2410_IISFCON_RXENABLE;
+        iisfcon &= ~S3C2410_IISFCON_RXDMA;
+        iiscon  |= S3C2410_IISCON_RXIDLE;
+        iiscon  &= ~S3C2410_IISCON_RXDMAEN;
+		iismod  &= ~S3C2410_IISMOD_RXMODE;
+
+		writel(iisfcon, s3c24xx_i2s.regs + S3C2410_IISFCON);
+		writel(iiscon,  s3c24xx_i2s.regs + S3C2410_IISCON);
+		writel(iismod,  s3c24xx_i2s.regs + S3C2410_IISMOD);
+	}
+
+	DBG("w: IISCON: %lx IISMOD: %lx IISFCON: %lx\n", iiscon, iismod, iisfcon);
+}
+
+/*
+ * Wait for the LR signal to allow synchronisation to the L/R clock
+ * from the codec. May only be needed for slave mode.
+ */
+static int s3c24xx_snd_lrsync(void)
+{
+	u32 iiscon;
+	unsigned long timeout = jiffies + msecs_to_jiffies(5);
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	while (1) {
+		iiscon = readl(s3c24xx_i2s.regs + S3C2410_IISCON);
+		if (iiscon & S3C2410_IISCON_LRINDEX)
+			break;
+
+		if (timeout < jiffies)
+			return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+/*
+ * Check whether CPU is the master or slave
+ */
+static inline int s3c24xx_snd_is_clkmaster(void)
+{
+	DBG("Entered %s\n", __FUNCTION__);
+
+	return (readl(s3c24xx_i2s.regs + S3C2410_IISMOD) & S3C2410_IISMOD_SLAVE) ? 0:1;
+}
+
+/*
+ * Set S3C24xx I2S DAI format
+ */
+static int s3c24xx_i2s_set_fmt(struct snd_soc_cpu_dai *cpu_dai,
+		unsigned int fmt)
+{
+	u32 iismod;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	iismod = readl(s3c24xx_i2s.regs + S3C2410_IISMOD);
+	DBG("hw_params r: IISMOD: %lx \n", iismod);
+
+	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+	case SND_SOC_DAIFMT_CBM_CFM:
+		iismod |= S3C2410_IISMOD_SLAVE;
+		break;
+	case SND_SOC_DAIFMT_CBS_CFS:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_LEFT_J:
+		iismod |= S3C2410_IISMOD_MSB;
+		break;
+	case SND_SOC_DAIFMT_I2S:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel(iismod, s3c24xx_i2s.regs + S3C2410_IISMOD);
+	DBG("hw_params w: IISMOD: %lx \n", iismod);
+	return 0;
+}
+
+static int s3c24xx_i2s_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	u32 iismod;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+		rtd->dai->cpu_dai->dma_data = &s3c24xx_i2s_pcm_stereo_out;
+	else
+		rtd->dai->cpu_dai->dma_data = &s3c24xx_i2s_pcm_stereo_in;
+
+	/* Working copies of register */
+	iismod = readl(s3c24xx_i2s.regs + S3C2410_IISMOD);
+	DBG("hw_params r: IISMOD: %lx\n", iismod);
+
+	switch (params_format(params)) {
+	case SNDRV_PCM_FORMAT_S8:
+		break;
+	case SNDRV_PCM_FORMAT_S16_LE:
+		iismod |= S3C2410_IISMOD_16BIT;
+		break;
+	}
+
+	writel(iismod, s3c24xx_i2s.regs + S3C2410_IISMOD);
+	DBG("hw_params w: IISMOD: %lx\n", iismod);
+	return 0;
+}
+
+static int s3c24xx_i2s_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	int ret = 0;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (!s3c24xx_snd_is_clkmaster()) {
+			ret = s3c24xx_snd_lrsync();
+			if (ret)
+				goto exit_err;
+		}
+
+		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+			s3c24xx_snd_rxctrl(1);
+		else
+			s3c24xx_snd_txctrl(1);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
+			s3c24xx_snd_rxctrl(0);
+		else
+			s3c24xx_snd_txctrl(0);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+exit_err:
+	return ret;
+}
+
+/*
+ * Set S3C24xx Clock source
+ */
+static int s3c24xx_i2s_set_sysclk(struct snd_soc_cpu_dai *cpu_dai,
+	int clk_id, unsigned int freq, int dir)
+{
+	u32 iismod = readl(s3c24xx_i2s.regs + S3C2410_IISMOD);
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	iismod &= ~S3C2440_IISMOD_MPLL;
+
+	switch (clk_id) {
+	case S3C24XX_CLKSRC_PCLK:
+		break;
+	case S3C24XX_CLKSRC_MPLL:
+		iismod |= S3C2440_IISMOD_MPLL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	writel(iismod, s3c24xx_i2s.regs + S3C2410_IISMOD);
+	return 0;
+}
+
+/*
+ * Set S3C24xx Clock dividers
+ */
+static int s3c24xx_i2s_set_clkdiv(struct snd_soc_cpu_dai *cpu_dai,
+	int div_id, int div)
+{
+	u32 reg;
+
+	DBG("Entered %s\n", __FUNCTION__);
+
+	switch (div_id) {
+	case S3C24XX_DIV_MCLK:
+		reg = readl(s3c24xx_i2s.regs + S3C2410_IISMOD) & ~S3C2410_IISMOD_FS_MASK;
+		writel(reg | div, s3c24xx_i2s.regs + S3C2410_IISMOD);
+		break;
+	case S3C24XX_DIV_BCLK:
+		reg = readl(s3c24xx_i2s.regs + S3C2410_IISMOD) & ~(S3C2410_IISMOD_384FS);
+		writel(reg | div, s3c24xx_i2s.regs + S3C2410_IISMOD);
+		break;
+	case S3C24XX_DIV_PRESCALER:
+		writel(div, s3c24xx_i2s.regs + S3C2410_IISPSR);
+		reg = readl(s3c24xx_i2s.regs + S3C2410_IISCON);
+		writel(reg | S3C2410_IISCON_PSCEN, s3c24xx_i2s.regs + S3C2410_IISCON);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * To avoid duplicating clock code, allow machine driver to
+ * get the clockrate from here.
+ */
+u32 s3c24xx_i2s_get_clockrate(void)
+{
+	return clk_get_rate(s3c24xx_i2s.iis_clk);
+}
+EXPORT_SYMBOL_GPL(s3c24xx_i2s_get_clockrate);
+
+static int s3c24xx_i2s_probe(struct platform_device *pdev)
+{
+	DBG("Entered %s\n", __FUNCTION__);
+
+	s3c24xx_i2s.regs = ioremap(S3C2410_PA_IIS, 0x100);
+	if (s3c24xx_i2s.regs == NULL)
+		return -ENXIO;
+
+	s3c24xx_i2s.iis_clk=clk_get(&pdev->dev, "iis");
+	if (s3c24xx_i2s.iis_clk == NULL) {
+		DBG("failed to get iis_clock\n");
+		return -ENODEV;
+	}
+	clk_enable(s3c24xx_i2s.iis_clk);
+
+	/* Configure the I2S pins in correct mode */
+	s3c2410_gpio_cfgpin(S3C2410_GPE0, S3C2410_GPE0_I2SLRCK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE1, S3C2410_GPE1_I2SSCLK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE2, S3C2410_GPE2_CDCLK);
+	s3c2410_gpio_cfgpin(S3C2410_GPE3, S3C2410_GPE3_I2SSDI);
+	s3c2410_gpio_cfgpin(S3C2410_GPE4, S3C2410_GPE4_I2SSDO);
+
+	writel(S3C2410_IISCON_IISEN, s3c24xx_i2s.regs + S3C2410_IISCON);
+
+	s3c24xx_snd_txctrl(0);
+	s3c24xx_snd_rxctrl(0);
+
+	return 0;
+}
+
+#define S3C24XX_I2S_RATES \
+	(SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 | SNDRV_PCM_RATE_16000 | \
+	SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
+	SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000)
+
+struct snd_soc_cpu_dai s3c24xx_i2s_dai = {
+	.name = "s3c24xx-i2s",
+	.id = 0,
+	.type = SND_SOC_DAI_I2S,
+	.probe = s3c24xx_i2s_probe,
+	.playback = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = S3C24XX_I2S_RATES,
+		.formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,},
+	.capture = {
+		.channels_min = 2,
+		.channels_max = 2,
+		.rates = S3C24XX_I2S_RATES,
+		.formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,},
+	.ops = {
+		.trigger = s3c24xx_i2s_trigger,
+		.hw_params = s3c24xx_i2s_hw_params,},
+	.dai_ops = {
+		.set_fmt = s3c24xx_i2s_set_fmt,
+		.set_clkdiv = s3c24xx_i2s_set_clkdiv,
+		.set_sysclk = s3c24xx_i2s_set_sysclk,
+	},
+};
+EXPORT_SYMBOL_GPL(s3c24xx_i2s_dai);
+
+/* Module information */
+MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
+MODULE_DESCRIPTION("s3c24xx I2S SoC Interface");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/s3c24xx/s3c24xx-i2s.h b/sound/soc/s3c24xx/s3c24xx-i2s.h
new file mode 100644
index 0000000..f9ca04e
--- /dev/null
+++ b/sound/soc/s3c24xx/s3c24xx-i2s.h
@@ -0,0 +1,35 @@
+/*
+ * s3c24xx-i2s.c  --  ALSA Soc Audio Layer
+ *
+ * Copyright 2005 Wolfson Microelectronics PLC.
+ * Author: Graeme Gregory
+ *         graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ *  Revision history
+ *    10th Nov 2006   Initial version.
+ */
+
+#ifndef S3C24XXI2S_H_
+#define S3C24XXI2S_H_
+
+/* clock sources */
+#define S3C24XX_CLKSRC_PCLK 0
+#define S3C24XX_CLKSRC_MPLL 1
+
+/* Clock dividers */
+#define S3C24XX_DIV_MCLK	0
+#define S3C24XX_DIV_BCLK	1
+#define S3C24XX_DIV_PRESCALER	2
+
+/* prescaler */
+#define S3C24XX_PRESCALE(a,b) \
+	(((a - 1) << S3C2410_IISPSR_INTSHIFT) | ((b - 1) << S3C2410_IISPSR_EXTSHFIT))
+
+u32 s3c24xx_i2s_get_clockrate(void);
+
+#endif /*S3C24XXI2S_H_*/