sound/soc/samsung/s3c-i2s-v2.c - arm/linux-arm-legacy - Git at Google

 /* ALSA Soc Audio Layer - I2S core for newer Samsung SoCs.
  *
  * Copyright (c) 2006 Wolfson Microelectronics PLC.
  *	Graeme Gregory graeme.gregory@wolfsonmicro.com
  *	linux@wolfsonmicro.com
  *
  * Copyright (c) 2008, 2007, 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.
  */

 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/clk.h>
 #include <linux/io.h>

 #include <sound/soc.h>
 #include <sound/pcm_params.h>

 #include <mach/dma.h>

 #include "regs-i2s-v2.h"
 #include "s3c-i2s-v2.h"
 #include "dma.h"

 #undef S3C_IIS_V2_SUPPORTED

 #if defined(CONFIG_CPU_S3C2412) || defined(CONFIG_CPU_S3C2413) \
 	|| defined(CONFIG_ARCH_S3C64XX) || defined(CONFIG_CPU_S5PV210)
 #define S3C_IIS_V2_SUPPORTED
 #endif

 #ifndef S3C_IIS_V2_SUPPORTED
 #error Unsupported CPU model
 #endif

 #define S3C2412_I2S_DEBUG_CON 0

 static inline struct s3c_i2sv2_info *to_info(struct snd_soc_dai *cpu_dai)
 {
 	return snd_soc_dai_get_drvdata(cpu_dai);
 }

 #define bit_set(v, b) (((v) & (b)) ? 1 : 0)

 #if S3C2412_I2S_DEBUG_CON
 static void dbg_showcon(const char *fn, u32 con)
 {
 	printk(KERN_DEBUG "%s: LRI=%d, TXFEMPT=%d, RXFEMPT=%d, TXFFULL=%d, RXFFULL=%d\n", fn,
 	       bit_set(con, S3C2412_IISCON_LRINDEX),
 	       bit_set(con, S3C2412_IISCON_TXFIFO_EMPTY),
 	       bit_set(con, S3C2412_IISCON_RXFIFO_EMPTY),
 	       bit_set(con, S3C2412_IISCON_TXFIFO_FULL),
 	       bit_set(con, S3C2412_IISCON_RXFIFO_FULL));

 	printk(KERN_DEBUG "%s: PAUSE: TXDMA=%d, RXDMA=%d, TXCH=%d, RXCH=%d\n",
 	       fn,
 	       bit_set(con, S3C2412_IISCON_TXDMA_PAUSE),
 	       bit_set(con, S3C2412_IISCON_RXDMA_PAUSE),
 	       bit_set(con, S3C2412_IISCON_TXCH_PAUSE),
 	       bit_set(con, S3C2412_IISCON_RXCH_PAUSE));
 	printk(KERN_DEBUG "%s: ACTIVE: TXDMA=%d, RXDMA=%d, IIS=%d\n", fn,
 	       bit_set(con, S3C2412_IISCON_TXDMA_ACTIVE),
 	       bit_set(con, S3C2412_IISCON_RXDMA_ACTIVE),
 	       bit_set(con, S3C2412_IISCON_IIS_ACTIVE));
 }
 #else
 static inline void dbg_showcon(const char *fn, u32 con)
 {
 }
 #endif


 /* Turn on or off the transmission path. */
 static void s3c2412_snd_txctrl(struct s3c_i2sv2_info *i2s, int on)
 {
 	void __iomem *regs = i2s->regs;
 	u32 fic, con, mod;

 	pr_debug("%s(%d)\n", __func__, on);

 	fic = readl(regs + S3C2412_IISFIC);
 	con = readl(regs + S3C2412_IISCON);
 	mod = readl(regs + S3C2412_IISMOD);

 	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);

 	if (on) {
 		con |= S3C2412_IISCON_TXDMA_ACTIVE | S3C2412_IISCON_IIS_ACTIVE;
 		con &= ~S3C2412_IISCON_TXDMA_PAUSE;
 		con &= ~S3C2412_IISCON_TXCH_PAUSE;

 		switch (mod & S3C2412_IISMOD_MODE_MASK) {
 		case S3C2412_IISMOD_MODE_TXONLY:
 		case S3C2412_IISMOD_MODE_TXRX:
 			/* do nothing, we are in the right mode */
 			break;

 		case S3C2412_IISMOD_MODE_RXONLY:
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			mod |= S3C2412_IISMOD_MODE_TXRX;
 			break;

 		default:
 			dev_err(i2s->dev, "TXEN: Invalid MODE %x in IISMOD\n",
 				mod & S3C2412_IISMOD_MODE_MASK);
 			break;
 		}

 		writel(con, regs + S3C2412_IISCON);
 		writel(mod, regs + S3C2412_IISMOD);
 	} else {
 		/* Note, we do not have any indication that the FIFO problems
 		 * tha the S3C2410/2440 had apply here, so we should be able
 		 * to disable the DMA and TX without resetting the FIFOS.
 		 */

 		con |=  S3C2412_IISCON_TXDMA_PAUSE;
 		con |=  S3C2412_IISCON_TXCH_PAUSE;
 		con &= ~S3C2412_IISCON_TXDMA_ACTIVE;

 		switch (mod & S3C2412_IISMOD_MODE_MASK) {
 		case S3C2412_IISMOD_MODE_TXRX:
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			mod |= S3C2412_IISMOD_MODE_RXONLY;
 			break;

 		case S3C2412_IISMOD_MODE_TXONLY:
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			con &= ~S3C2412_IISCON_IIS_ACTIVE;
 			break;

 		default:
 			dev_err(i2s->dev, "TXDIS: Invalid MODE %x in IISMOD\n",
 				mod & S3C2412_IISMOD_MODE_MASK);
 			break;
 		}

 		writel(mod, regs + S3C2412_IISMOD);
 		writel(con, regs + S3C2412_IISCON);
 	}

 	fic = readl(regs + S3C2412_IISFIC);
 	dbg_showcon(__func__, con);
 	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
 }

 static void s3c2412_snd_rxctrl(struct s3c_i2sv2_info *i2s, int on)
 {
 	void __iomem *regs = i2s->regs;
 	u32 fic, con, mod;

 	pr_debug("%s(%d)\n", __func__, on);

 	fic = readl(regs + S3C2412_IISFIC);
 	con = readl(regs + S3C2412_IISCON);
 	mod = readl(regs + S3C2412_IISMOD);

 	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);

 	if (on) {
 		con |= S3C2412_IISCON_RXDMA_ACTIVE | S3C2412_IISCON_IIS_ACTIVE;
 		con &= ~S3C2412_IISCON_RXDMA_PAUSE;
 		con &= ~S3C2412_IISCON_RXCH_PAUSE;

 		switch (mod & S3C2412_IISMOD_MODE_MASK) {
 		case S3C2412_IISMOD_MODE_TXRX:
 		case S3C2412_IISMOD_MODE_RXONLY:
 			/* do nothing, we are in the right mode */
 			break;

 		case S3C2412_IISMOD_MODE_TXONLY:
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			mod |= S3C2412_IISMOD_MODE_TXRX;
 			break;

 		default:
 			dev_err(i2s->dev, "RXEN: Invalid MODE %x in IISMOD\n",
 				mod & S3C2412_IISMOD_MODE_MASK);
 		}

 		writel(mod, regs + S3C2412_IISMOD);
 		writel(con, regs + S3C2412_IISCON);
 	} else {
 		/* See txctrl notes on FIFOs. */

 		con &= ~S3C2412_IISCON_RXDMA_ACTIVE;
 		con |=  S3C2412_IISCON_RXDMA_PAUSE;
 		con |=  S3C2412_IISCON_RXCH_PAUSE;

 		switch (mod & S3C2412_IISMOD_MODE_MASK) {
 		case S3C2412_IISMOD_MODE_RXONLY:
 			con &= ~S3C2412_IISCON_IIS_ACTIVE;
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			break;

 		case S3C2412_IISMOD_MODE_TXRX:
 			mod &= ~S3C2412_IISMOD_MODE_MASK;
 			mod |= S3C2412_IISMOD_MODE_TXONLY;
 			break;

 		default:
 			dev_err(i2s->dev, "RXDIS: Invalid MODE %x in IISMOD\n",
 				mod & S3C2412_IISMOD_MODE_MASK);
 		}

 		writel(con, regs + S3C2412_IISCON);
 		writel(mod, regs + S3C2412_IISMOD);
 	}

 	fic = readl(regs + S3C2412_IISFIC);
 	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
 }

 #define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)

 /*
  * 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 s3c2412_snd_lrsync(struct s3c_i2sv2_info *i2s)
 {
 	u32 iiscon;
 	unsigned long loops = msecs_to_loops(5);

 	pr_debug("Entered %s\n", __func__);

 	while (--loops) {
 		iiscon = readl(i2s->regs + S3C2412_IISCON);
 		if (iiscon & S3C2412_IISCON_LRINDEX)
 			break;

 		cpu_relax();
 	}

 	if (!loops) {
 		printk(KERN_ERR "%s: timeout\n", __func__);
 		return -ETIMEDOUT;
 	}

 	return 0;
 }

 /*
  * Set S3C2412 I2S DAI format
  */
 static int s3c2412_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
 			       unsigned int fmt)
 {
 	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
 	u32 iismod;

 	pr_debug("Entered %s\n", __func__);

 	iismod = readl(i2s->regs + S3C2412_IISMOD);
 	pr_debug("hw_params r: IISMOD: %x \n", iismod);

 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 	case SND_SOC_DAIFMT_CBM_CFM:
 		i2s->master = 0;
 		iismod |= S3C2412_IISMOD_SLAVE;
 		break;
 	case SND_SOC_DAIFMT_CBS_CFS:
 		i2s->master = 1;
 		iismod &= ~S3C2412_IISMOD_SLAVE;
 		break;
 	default:
 		pr_err("unknwon master/slave format\n");
 		return -EINVAL;
 	}

 	iismod &= ~S3C2412_IISMOD_SDF_MASK;

 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 	case SND_SOC_DAIFMT_RIGHT_J:
 		iismod |= S3C2412_IISMOD_LR_RLOW;
 		iismod |= S3C2412_IISMOD_SDF_MSB;
 		break;
 	case SND_SOC_DAIFMT_LEFT_J:
 		iismod |= S3C2412_IISMOD_LR_RLOW;
 		iismod |= S3C2412_IISMOD_SDF_LSB;
 		break;
 	case SND_SOC_DAIFMT_I2S:
 		iismod &= ~S3C2412_IISMOD_LR_RLOW;
 		iismod |= S3C2412_IISMOD_SDF_IIS;
 		break;
 	default:
 		pr_err("Unknown data format\n");
 		return -EINVAL;
 	}

 	writel(iismod, i2s->regs + S3C2412_IISMOD);
 	pr_debug("hw_params w: IISMOD: %x \n", iismod);
 	return 0;
 }

 static int s3c_i2sv2_hw_params(struct snd_pcm_substream *substream,
 				 struct snd_pcm_hw_params *params,
 				 struct snd_soc_dai *dai)
 {
 	struct s3c_i2sv2_info *i2s = to_info(dai);
 	struct s3c_dma_params *dma_data;
 	u32 iismod;

 	pr_debug("Entered %s\n", __func__);

 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		dma_data = i2s->dma_playback;
 	else
 		dma_data = i2s->dma_capture;

 	snd_soc_dai_set_dma_data(dai, substream, dma_data);

 	/* Working copies of register */
 	iismod = readl(i2s->regs + S3C2412_IISMOD);
 	pr_debug("%s: r: IISMOD: %x\n", __func__, iismod);

 	iismod &= ~S3C64XX_IISMOD_BLC_MASK;
 	/* Sample size */
 	switch (params_format(params)) {
 	case SNDRV_PCM_FORMAT_S8:
 		iismod |= S3C64XX_IISMOD_BLC_8BIT;
 		break;
 	case SNDRV_PCM_FORMAT_S16_LE:
 		break;
 	case SNDRV_PCM_FORMAT_S24_LE:
 		iismod |= S3C64XX_IISMOD_BLC_24BIT;
 		break;
 	}

 	writel(iismod, i2s->regs + S3C2412_IISMOD);
 	pr_debug("%s: w: IISMOD: %x\n", __func__, iismod);

 	return 0;
 }

 static int s3c_i2sv2_set_sysclk(struct snd_soc_dai *cpu_dai,
 				  int clk_id, unsigned int freq, int dir)
 {
 	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
 	u32 iismod = readl(i2s->regs + S3C2412_IISMOD);

 	pr_debug("Entered %s\n", __func__);
 	pr_debug("%s r: IISMOD: %x\n", __func__, iismod);

 	switch (clk_id) {
 	case S3C_I2SV2_CLKSRC_PCLK:
 		iismod &= ~S3C2412_IISMOD_IMS_SYSMUX;
 		break;

 	case S3C_I2SV2_CLKSRC_AUDIOBUS:
 		iismod |= S3C2412_IISMOD_IMS_SYSMUX;
 		break;

 	case S3C_I2SV2_CLKSRC_CDCLK:
 		/* Error if controller doesn't have the CDCLKCON bit */
 		if (!(i2s->feature & S3C_FEATURE_CDCLKCON))
 			return -EINVAL;

 		switch (dir) {
 		case SND_SOC_CLOCK_IN:
 			iismod |= S3C64XX_IISMOD_CDCLKCON;
 			break;
 		case SND_SOC_CLOCK_OUT:
 			iismod &= ~S3C64XX_IISMOD_CDCLKCON;
 			break;
 		default:
 			return -EINVAL;
 		}
 		break;

 	default:
 		return -EINVAL;
 	}

 	writel(iismod, i2s->regs + S3C2412_IISMOD);
 	pr_debug("%s w: IISMOD: %x\n", __func__, iismod);

 	return 0;
 }

 static int s3c2412_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
 			       struct snd_soc_dai *dai)
 {
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 	struct s3c_i2sv2_info *i2s = to_info(rtd->cpu_dai);
 	int capture = (substream->stream == SNDRV_PCM_STREAM_CAPTURE);
 	unsigned long irqs;
 	int ret = 0;
 	struct s3c_dma_params *dma_data =
 		snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);

 	pr_debug("Entered %s\n", __func__);

 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 		/* On start, ensure that the FIFOs are cleared and reset. */

 		writel(capture ? S3C2412_IISFIC_RXFLUSH : S3C2412_IISFIC_TXFLUSH,
 		       i2s->regs + S3C2412_IISFIC);

 		/* clear again, just in case */
 		writel(0x0, i2s->regs + S3C2412_IISFIC);

 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		if (!i2s->master) {
 			ret = s3c2412_snd_lrsync(i2s);
 			if (ret)
 				goto exit_err;
 		}

 		local_irq_save(irqs);

 		if (capture)
 			s3c2412_snd_rxctrl(i2s, 1);
 		else
 			s3c2412_snd_txctrl(i2s, 1);

 		local_irq_restore(irqs);

 		/*
 		 * Load the next buffer to DMA to meet the reqirement
 		 * of the auto reload mechanism of S3C24XX.
 		 * This call won't bother S3C64XX.
 		 */
 		s3c2410_dma_ctrl(dma_data->channel, S3C2410_DMAOP_STARTED);

 		break;

 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		local_irq_save(irqs);

 		if (capture)
 			s3c2412_snd_rxctrl(i2s, 0);
 		else
 			s3c2412_snd_txctrl(i2s, 0);

 		local_irq_restore(irqs);
 		break;
 	default:
 		ret = -EINVAL;
 		break;
 	}

 exit_err:
 	return ret;
 }

 /*
  * Set S3C2412 Clock dividers
  */
 static int s3c2412_i2s_set_clkdiv(struct snd_soc_dai *cpu_dai,
 				  int div_id, int div)
 {
 	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
 	u32 reg;

 	pr_debug("%s(%p, %d, %d)\n", __func__, cpu_dai, div_id, div);

 	switch (div_id) {
 	case S3C_I2SV2_DIV_BCLK:
 		switch (div) {
 		case 16:
 			div = S3C2412_IISMOD_BCLK_16FS;
 			break;

 		case 32:
 			div = S3C2412_IISMOD_BCLK_32FS;
 			break;

 		case 24:
 			div = S3C2412_IISMOD_BCLK_24FS;
 			break;

 		case 48:
 			div = S3C2412_IISMOD_BCLK_48FS;
 			break;

 		default:
 			return -EINVAL;
 		}

 		reg = readl(i2s->regs + S3C2412_IISMOD);
 		reg &= ~S3C2412_IISMOD_BCLK_MASK;
 		writel(reg | div, i2s->regs + S3C2412_IISMOD);

 		pr_debug("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
 		break;

 	case S3C_I2SV2_DIV_RCLK:
 		switch (div) {
 		case 256:
 			div = S3C2412_IISMOD_RCLK_256FS;
 			break;

 		case 384:
 			div = S3C2412_IISMOD_RCLK_384FS;
 			break;

 		case 512:
 			div = S3C2412_IISMOD_RCLK_512FS;
 			break;

 		case 768:
 			div = S3C2412_IISMOD_RCLK_768FS;
 			break;

 		default:
 			return -EINVAL;
 		}

 		reg = readl(i2s->regs + S3C2412_IISMOD);
 		reg &= ~S3C2412_IISMOD_RCLK_MASK;
 		writel(reg | div, i2s->regs + S3C2412_IISMOD);
 		pr_debug("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
 		break;

 	case S3C_I2SV2_DIV_PRESCALER:
 		if (div >= 0) {
 			writel((div << 8) | S3C2412_IISPSR_PSREN,
 			       i2s->regs + S3C2412_IISPSR);
 		} else {
 			writel(0x0, i2s->regs + S3C2412_IISPSR);
 		}
 		pr_debug("%s: PSR=%08x\n", __func__, readl(i2s->regs + S3C2412_IISPSR));
 		break;

 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static snd_pcm_sframes_t s3c2412_i2s_delay(struct snd_pcm_substream *substream,
 					   struct snd_soc_dai *dai)
 {
 	struct s3c_i2sv2_info *i2s = to_info(dai);
 	u32 reg = readl(i2s->regs + S3C2412_IISFIC);
 	snd_pcm_sframes_t delay;

 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		delay = S3C2412_IISFIC_TXCOUNT(reg);
 	else
 		delay = S3C2412_IISFIC_RXCOUNT(reg);

 	return delay;
 }

 struct clk *s3c_i2sv2_get_clock(struct snd_soc_dai *cpu_dai)
 {
 	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
 	u32 iismod = readl(i2s->regs + S3C2412_IISMOD);

 	if (iismod & S3C2412_IISMOD_IMS_SYSMUX)
 		return i2s->iis_cclk;
 	else
 		return i2s->iis_pclk;
 }
 EXPORT_SYMBOL_GPL(s3c_i2sv2_get_clock);

 /* default table of all avaialable root fs divisors */
 static unsigned int iis_fs_tab[] = { 256, 512, 384, 768 };

 int s3c_i2sv2_iis_calc_rate(struct s3c_i2sv2_rate_calc *info,
 			    unsigned int *fstab,
 			    unsigned int rate, struct clk *clk)
 {
 	unsigned long clkrate = clk_get_rate(clk);
 	unsigned int div;
 	unsigned int fsclk;
 	unsigned int actual;
 	unsigned int fs;
 	unsigned int fsdiv;
 	signed int deviation = 0;
 	unsigned int best_fs = 0;
 	unsigned int best_div = 0;
 	unsigned int best_rate = 0;
 	unsigned int best_deviation = INT_MAX;

 	pr_debug("Input clock rate %ldHz\n", clkrate);

 	if (fstab == NULL)
 		fstab = iis_fs_tab;

 	for (fs = 0; fs < ARRAY_SIZE(iis_fs_tab); fs++) {
 		fsdiv = iis_fs_tab[fs];

 		fsclk = clkrate / fsdiv;
 		div = fsclk / rate;

 		if ((fsclk % rate) > (rate / 2))
 			div++;

 		if (div <= 1)
 			continue;

 		actual = clkrate / (fsdiv * div);
 		deviation = actual - rate;

 		printk(KERN_DEBUG "%ufs: div %u => result %u, deviation %d\n",
 		       fsdiv, div, actual, deviation);

 		deviation = abs(deviation);

 		if (deviation < best_deviation) {
 			best_fs = fsdiv;
 			best_div = div;
 			best_rate = actual;
 			best_deviation = deviation;
 		}

 		if (deviation == 0)
 			break;
 	}

 	printk(KERN_DEBUG "best: fs=%u, div=%u, rate=%u\n",
 	       best_fs, best_div, best_rate);

 	info->fs_div = best_fs;
 	info->clk_div = best_div;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(s3c_i2sv2_iis_calc_rate);

 int s3c_i2sv2_probe(struct snd_soc_dai *dai,
 		    struct s3c_i2sv2_info *i2s,
 		    unsigned long base)
 {
 	struct device *dev = dai->dev;
 	unsigned int iismod;

 	i2s->dev = dev;

 	/* record our i2s structure for later use in the callbacks */
 	snd_soc_dai_set_drvdata(dai, i2s);

 	i2s->regs = ioremap(base, 0x100);
 	if (i2s->regs == NULL) {
 		dev_err(dev, "cannot ioremap registers\n");
 		return -ENXIO;
 	}

 	i2s->iis_pclk = clk_get(dev, "iis");
 	if (IS_ERR(i2s->iis_pclk)) {
 		dev_err(dev, "failed to get iis_clock\n");
 		iounmap(i2s->regs);
 		return -ENOENT;
 	}

 	clk_enable(i2s->iis_pclk);

 	/* Mark ourselves as in TXRX mode so we can run through our cleanup
 	 * process without warnings. */
 	iismod = readl(i2s->regs + S3C2412_IISMOD);
 	iismod |= S3C2412_IISMOD_MODE_TXRX;
 	writel(iismod, i2s->regs + S3C2412_IISMOD);
 	s3c2412_snd_txctrl(i2s, 0);
 	s3c2412_snd_rxctrl(i2s, 0);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(s3c_i2sv2_probe);

 #ifdef CONFIG_PM
 static int s3c2412_i2s_suspend(struct snd_soc_dai *dai)
 {
 	struct s3c_i2sv2_info *i2s = to_info(dai);
 	u32 iismod;

 	if (dai->active) {
 		i2s->suspend_iismod = readl(i2s->regs + S3C2412_IISMOD);
 		i2s->suspend_iiscon = readl(i2s->regs + S3C2412_IISCON);
 		i2s->suspend_iispsr = readl(i2s->regs + S3C2412_IISPSR);

 		/* some basic suspend checks */

 		iismod = readl(i2s->regs + S3C2412_IISMOD);

 		if (iismod & S3C2412_IISCON_RXDMA_ACTIVE)
 			pr_warning("%s: RXDMA active?\n", __func__);

 		if (iismod & S3C2412_IISCON_TXDMA_ACTIVE)
 			pr_warning("%s: TXDMA active?\n", __func__);

 		if (iismod & S3C2412_IISCON_IIS_ACTIVE)
 			pr_warning("%s: IIS active\n", __func__);
 	}

 	return 0;
 }

 static int s3c2412_i2s_resume(struct snd_soc_dai *dai)
 {
 	struct s3c_i2sv2_info *i2s = to_info(dai);

 	pr_info("dai_active %d, IISMOD %08x, IISCON %08x\n",
 		dai->active, i2s->suspend_iismod, i2s->suspend_iiscon);

 	if (dai->active) {
 		writel(i2s->suspend_iiscon, i2s->regs + S3C2412_IISCON);
 		writel(i2s->suspend_iismod, i2s->regs + S3C2412_IISMOD);
 		writel(i2s->suspend_iispsr, i2s->regs + S3C2412_IISPSR);

 		writel(S3C2412_IISFIC_RXFLUSH | S3C2412_IISFIC_TXFLUSH,
 		       i2s->regs + S3C2412_IISFIC);

 		ndelay(250);
 		writel(0x0, i2s->regs + S3C2412_IISFIC);
 	}

 	return 0;
 }
 #else
 #define s3c2412_i2s_suspend NULL
 #define s3c2412_i2s_resume  NULL
 #endif

 int s3c_i2sv2_register_component(struct device *dev, int id,
 			   struct snd_soc_component_driver *cmp_drv,
 			   struct snd_soc_dai_driver *dai_drv)
 {
 	struct snd_soc_dai_ops *ops = dai_drv->ops;

 	ops->trigger = s3c2412_i2s_trigger;
 	if (!ops->hw_params)
 		ops->hw_params = s3c_i2sv2_hw_params;
 	ops->set_fmt = s3c2412_i2s_set_fmt;
 	ops->set_clkdiv = s3c2412_i2s_set_clkdiv;
 	ops->set_sysclk = s3c_i2sv2_set_sysclk;

 	/* Allow overriding by (for example) IISv4 */
 	if (!ops->delay)
 		ops->delay = s3c2412_i2s_delay;

 	dai_drv->suspend = s3c2412_i2s_suspend;
 	dai_drv->resume = s3c2412_i2s_resume;

 	return snd_soc_register_component(dev, cmp_drv, dai_drv, 1);
 }
 EXPORT_SYMBOL_GPL(s3c_i2sv2_register_component);

 MODULE_LICENSE("GPL");
	/* ALSA Soc Audio Layer - I2S core for newer Samsung SoCs.
	*
	* Copyright (c) 2006 Wolfson Microelectronics PLC.
	* Graeme Gregory graeme.gregory@wolfsonmicro.com
	* linux@wolfsonmicro.com
	*
	* Copyright (c) 2008, 2007, 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.
	*/

	#include <linux/module.h>
	#include <linux/delay.h>
	#include <linux/clk.h>
	#include <linux/io.h>

	#include <sound/soc.h>
	#include <sound/pcm_params.h>

	#include <mach/dma.h>

	#include "regs-i2s-v2.h"
	#include "s3c-i2s-v2.h"
	#include "dma.h"

	#undef S3C_IIS_V2_SUPPORTED

	#if defined(CONFIG_CPU_S3C2412) \|\| defined(CONFIG_CPU_S3C2413) \
	\|\| defined(CONFIG_ARCH_S3C64XX) \|\| defined(CONFIG_CPU_S5PV210)
	#define S3C_IIS_V2_SUPPORTED
	#endif

	#ifndef S3C_IIS_V2_SUPPORTED
	#error Unsupported CPU model
	#endif

	#define S3C2412_I2S_DEBUG_CON 0

	static inline struct s3c_i2sv2_info to_info(struct snd_soc_dai cpu_dai)
	{
	return snd_soc_dai_get_drvdata(cpu_dai);
	}

	#define bit_set(v, b) (((v) & (b)) ? 1 : 0)

	#if S3C2412_I2S_DEBUG_CON
	static void dbg_showcon(const char *fn, u32 con)
	{
	printk(KERN_DEBUG "%s: LRI=%d, TXFEMPT=%d, RXFEMPT=%d, TXFFULL=%d, RXFFULL=%d\n", fn,
	bit_set(con, S3C2412_IISCON_LRINDEX),
	bit_set(con, S3C2412_IISCON_TXFIFO_EMPTY),
	bit_set(con, S3C2412_IISCON_RXFIFO_EMPTY),
	bit_set(con, S3C2412_IISCON_TXFIFO_FULL),
	bit_set(con, S3C2412_IISCON_RXFIFO_FULL));

	printk(KERN_DEBUG "%s: PAUSE: TXDMA=%d, RXDMA=%d, TXCH=%d, RXCH=%d\n",
	fn,
	bit_set(con, S3C2412_IISCON_TXDMA_PAUSE),
	bit_set(con, S3C2412_IISCON_RXDMA_PAUSE),
	bit_set(con, S3C2412_IISCON_TXCH_PAUSE),
	bit_set(con, S3C2412_IISCON_RXCH_PAUSE));
	printk(KERN_DEBUG "%s: ACTIVE: TXDMA=%d, RXDMA=%d, IIS=%d\n", fn,
	bit_set(con, S3C2412_IISCON_TXDMA_ACTIVE),
	bit_set(con, S3C2412_IISCON_RXDMA_ACTIVE),
	bit_set(con, S3C2412_IISCON_IIS_ACTIVE));
	}
	#else
	static inline void dbg_showcon(const char *fn, u32 con)
	{
	}
	#endif


	/* Turn on or off the transmission path. */
	static void s3c2412_snd_txctrl(struct s3c_i2sv2_info *i2s, int on)
	{
	void __iomem *regs = i2s->regs;
	u32 fic, con, mod;

	pr_debug("%s(%d)\n", __func__, on);

	fic = readl(regs + S3C2412_IISFIC);
	con = readl(regs + S3C2412_IISCON);
	mod = readl(regs + S3C2412_IISMOD);

	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);

	if (on) {
	con \|= S3C2412_IISCON_TXDMA_ACTIVE \| S3C2412_IISCON_IIS_ACTIVE;
	con &= ~S3C2412_IISCON_TXDMA_PAUSE;
	con &= ~S3C2412_IISCON_TXCH_PAUSE;

	switch (mod & S3C2412_IISMOD_MODE_MASK) {
	case S3C2412_IISMOD_MODE_TXONLY:
	case S3C2412_IISMOD_MODE_TXRX:
	/* do nothing, we are in the right mode */
	break;

	case S3C2412_IISMOD_MODE_RXONLY:
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	mod \|= S3C2412_IISMOD_MODE_TXRX;
	break;

	default:
	dev_err(i2s->dev, "TXEN: Invalid MODE %x in IISMOD\n",
	mod & S3C2412_IISMOD_MODE_MASK);
	break;
	}

	writel(con, regs + S3C2412_IISCON);
	writel(mod, regs + S3C2412_IISMOD);
	} else {
	/* Note, we do not have any indication that the FIFO problems
	* tha the S3C2410/2440 had apply here, so we should be able
	* to disable the DMA and TX without resetting the FIFOS.
	*/

	con \|= S3C2412_IISCON_TXDMA_PAUSE;
	con \|= S3C2412_IISCON_TXCH_PAUSE;
	con &= ~S3C2412_IISCON_TXDMA_ACTIVE;

	switch (mod & S3C2412_IISMOD_MODE_MASK) {
	case S3C2412_IISMOD_MODE_TXRX:
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	mod \|= S3C2412_IISMOD_MODE_RXONLY;
	break;

	case S3C2412_IISMOD_MODE_TXONLY:
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	con &= ~S3C2412_IISCON_IIS_ACTIVE;
	break;

	default:
	dev_err(i2s->dev, "TXDIS: Invalid MODE %x in IISMOD\n",
	mod & S3C2412_IISMOD_MODE_MASK);
	break;
	}

	writel(mod, regs + S3C2412_IISMOD);
	writel(con, regs + S3C2412_IISCON);
	}

	fic = readl(regs + S3C2412_IISFIC);
	dbg_showcon(__func__, con);
	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
	}

	static void s3c2412_snd_rxctrl(struct s3c_i2sv2_info *i2s, int on)
	{
	void __iomem *regs = i2s->regs;
	u32 fic, con, mod;

	pr_debug("%s(%d)\n", __func__, on);

	fic = readl(regs + S3C2412_IISFIC);
	con = readl(regs + S3C2412_IISCON);
	mod = readl(regs + S3C2412_IISMOD);

	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);

	if (on) {
	con \|= S3C2412_IISCON_RXDMA_ACTIVE \| S3C2412_IISCON_IIS_ACTIVE;
	con &= ~S3C2412_IISCON_RXDMA_PAUSE;
	con &= ~S3C2412_IISCON_RXCH_PAUSE;

	switch (mod & S3C2412_IISMOD_MODE_MASK) {
	case S3C2412_IISMOD_MODE_TXRX:
	case S3C2412_IISMOD_MODE_RXONLY:
	/* do nothing, we are in the right mode */
	break;

	case S3C2412_IISMOD_MODE_TXONLY:
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	mod \|= S3C2412_IISMOD_MODE_TXRX;
	break;

	default:
	dev_err(i2s->dev, "RXEN: Invalid MODE %x in IISMOD\n",
	mod & S3C2412_IISMOD_MODE_MASK);
	}

	writel(mod, regs + S3C2412_IISMOD);
	writel(con, regs + S3C2412_IISCON);
	} else {
	/* See txctrl notes on FIFOs. */

	con &= ~S3C2412_IISCON_RXDMA_ACTIVE;
	con \|= S3C2412_IISCON_RXDMA_PAUSE;
	con \|= S3C2412_IISCON_RXCH_PAUSE;

	switch (mod & S3C2412_IISMOD_MODE_MASK) {
	case S3C2412_IISMOD_MODE_RXONLY:
	con &= ~S3C2412_IISCON_IIS_ACTIVE;
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	break;

	case S3C2412_IISMOD_MODE_TXRX:
	mod &= ~S3C2412_IISMOD_MODE_MASK;
	mod \|= S3C2412_IISMOD_MODE_TXONLY;
	break;

	default:
	dev_err(i2s->dev, "RXDIS: Invalid MODE %x in IISMOD\n",
	mod & S3C2412_IISMOD_MODE_MASK);
	}

	writel(con, regs + S3C2412_IISCON);
	writel(mod, regs + S3C2412_IISMOD);
	}

	fic = readl(regs + S3C2412_IISFIC);
	pr_debug("%s: IIS: CON=%x MOD=%x FIC=%x\n", __func__, con, mod, fic);
	}

	#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)

	/*
	* 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 s3c2412_snd_lrsync(struct s3c_i2sv2_info *i2s)
	{
	u32 iiscon;
	unsigned long loops = msecs_to_loops(5);

	pr_debug("Entered %s\n", __func__);

	while (--loops) {
	iiscon = readl(i2s->regs + S3C2412_IISCON);
	if (iiscon & S3C2412_IISCON_LRINDEX)
	break;

	cpu_relax();
	}

	if (!loops) {
	printk(KERN_ERR "%s: timeout\n", __func__);
	return -ETIMEDOUT;
	}

	return 0;
	}

	/*
	* Set S3C2412 I2S DAI format
	*/
	static int s3c2412_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
	unsigned int fmt)
	{
	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
	u32 iismod;

	pr_debug("Entered %s\n", __func__);

	iismod = readl(i2s->regs + S3C2412_IISMOD);
	pr_debug("hw_params r: IISMOD: %x \n", iismod);

	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
	case SND_SOC_DAIFMT_CBM_CFM:
	i2s->master = 0;
	iismod \|= S3C2412_IISMOD_SLAVE;
	break;
	case SND_SOC_DAIFMT_CBS_CFS:
	i2s->master = 1;
	iismod &= ~S3C2412_IISMOD_SLAVE;
	break;
	default:
	pr_err("unknwon master/slave format\n");
	return -EINVAL;
	}

	iismod &= ~S3C2412_IISMOD_SDF_MASK;

	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
	case SND_SOC_DAIFMT_RIGHT_J:
	iismod \|= S3C2412_IISMOD_LR_RLOW;
	iismod \|= S3C2412_IISMOD_SDF_MSB;
	break;
	case SND_SOC_DAIFMT_LEFT_J:
	iismod \|= S3C2412_IISMOD_LR_RLOW;
	iismod \|= S3C2412_IISMOD_SDF_LSB;
	break;
	case SND_SOC_DAIFMT_I2S:
	iismod &= ~S3C2412_IISMOD_LR_RLOW;
	iismod \|= S3C2412_IISMOD_SDF_IIS;
	break;
	default:
	pr_err("Unknown data format\n");
	return -EINVAL;
	}

	writel(iismod, i2s->regs + S3C2412_IISMOD);
	pr_debug("hw_params w: IISMOD: %x \n", iismod);
	return 0;
	}

	static int s3c_i2sv2_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params,
	struct snd_soc_dai *dai)
	{
	struct s3c_i2sv2_info *i2s = to_info(dai);
	struct s3c_dma_params *dma_data;
	u32 iismod;

	pr_debug("Entered %s\n", __func__);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
	dma_data = i2s->dma_playback;
	else
	dma_data = i2s->dma_capture;

	snd_soc_dai_set_dma_data(dai, substream, dma_data);

	/* Working copies of register */
	iismod = readl(i2s->regs + S3C2412_IISMOD);
	pr_debug("%s: r: IISMOD: %x\n", __func__, iismod);

	iismod &= ~S3C64XX_IISMOD_BLC_MASK;
	/* Sample size */
	switch (params_format(params)) {
	case SNDRV_PCM_FORMAT_S8:
	iismod \|= S3C64XX_IISMOD_BLC_8BIT;
	break;
	case SNDRV_PCM_FORMAT_S16_LE:
	break;
	case SNDRV_PCM_FORMAT_S24_LE:
	iismod \|= S3C64XX_IISMOD_BLC_24BIT;
	break;
	}

	writel(iismod, i2s->regs + S3C2412_IISMOD);
	pr_debug("%s: w: IISMOD: %x\n", __func__, iismod);

	return 0;
	}

	static int s3c_i2sv2_set_sysclk(struct snd_soc_dai *cpu_dai,
	int clk_id, unsigned int freq, int dir)
	{
	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
	u32 iismod = readl(i2s->regs + S3C2412_IISMOD);

	pr_debug("Entered %s\n", __func__);
	pr_debug("%s r: IISMOD: %x\n", __func__, iismod);

	switch (clk_id) {
	case S3C_I2SV2_CLKSRC_PCLK:
	iismod &= ~S3C2412_IISMOD_IMS_SYSMUX;
	break;

	case S3C_I2SV2_CLKSRC_AUDIOBUS:
	iismod \|= S3C2412_IISMOD_IMS_SYSMUX;
	break;

	case S3C_I2SV2_CLKSRC_CDCLK:
	/* Error if controller doesn't have the CDCLKCON bit */
	if (!(i2s->feature & S3C_FEATURE_CDCLKCON))
	return -EINVAL;

	switch (dir) {
	case SND_SOC_CLOCK_IN:
	iismod \|= S3C64XX_IISMOD_CDCLKCON;
	break;
	case SND_SOC_CLOCK_OUT:
	iismod &= ~S3C64XX_IISMOD_CDCLKCON;
	break;
	default:
	return -EINVAL;
	}
	break;

	default:
	return -EINVAL;
	}

	writel(iismod, i2s->regs + S3C2412_IISMOD);
	pr_debug("%s w: IISMOD: %x\n", __func__, iismod);

	return 0;
	}

	static int s3c2412_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
	struct snd_soc_dai *dai)
	{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct s3c_i2sv2_info *i2s = to_info(rtd->cpu_dai);
	int capture = (substream->stream == SNDRV_PCM_STREAM_CAPTURE);
	unsigned long irqs;
	int ret = 0;
	struct s3c_dma_params *dma_data =
	snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);

	pr_debug("Entered %s\n", __func__);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	/* On start, ensure that the FIFOs are cleared and reset. */

	writel(capture ? S3C2412_IISFIC_RXFLUSH : S3C2412_IISFIC_TXFLUSH,
	i2s->regs + S3C2412_IISFIC);

	/* clear again, just in case */
	writel(0x0, i2s->regs + S3C2412_IISFIC);

	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	if (!i2s->master) {
	ret = s3c2412_snd_lrsync(i2s);
	if (ret)
	goto exit_err;
	}

	local_irq_save(irqs);

	if (capture)
	s3c2412_snd_rxctrl(i2s, 1);
	else
	s3c2412_snd_txctrl(i2s, 1);

	local_irq_restore(irqs);

	/*
	* Load the next buffer to DMA to meet the reqirement
	* of the auto reload mechanism of S3C24XX.
	* This call won't bother S3C64XX.
	*/
	s3c2410_dma_ctrl(dma_data->channel, S3C2410_DMAOP_STARTED);

	break;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	local_irq_save(irqs);

	if (capture)
	s3c2412_snd_rxctrl(i2s, 0);
	else
	s3c2412_snd_txctrl(i2s, 0);

	local_irq_restore(irqs);
	break;
	default:
	ret = -EINVAL;
	break;
	}

	exit_err:
	return ret;
	}

	/*
	* Set S3C2412 Clock dividers
	*/
	static int s3c2412_i2s_set_clkdiv(struct snd_soc_dai *cpu_dai,
	int div_id, int div)
	{
	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
	u32 reg;

	pr_debug("%s(%p, %d, %d)\n", __func__, cpu_dai, div_id, div);

	switch (div_id) {
	case S3C_I2SV2_DIV_BCLK:
	switch (div) {
	case 16:
	div = S3C2412_IISMOD_BCLK_16FS;
	break;

	case 32:
	div = S3C2412_IISMOD_BCLK_32FS;
	break;

	case 24:
	div = S3C2412_IISMOD_BCLK_24FS;
	break;

	case 48:
	div = S3C2412_IISMOD_BCLK_48FS;
	break;

	default:
	return -EINVAL;
	}

	reg = readl(i2s->regs + S3C2412_IISMOD);
	reg &= ~S3C2412_IISMOD_BCLK_MASK;
	writel(reg \| div, i2s->regs + S3C2412_IISMOD);

	pr_debug("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
	break;

	case S3C_I2SV2_DIV_RCLK:
	switch (div) {
	case 256:
	div = S3C2412_IISMOD_RCLK_256FS;
	break;

	case 384:
	div = S3C2412_IISMOD_RCLK_384FS;
	break;

	case 512:
	div = S3C2412_IISMOD_RCLK_512FS;
	break;

	case 768:
	div = S3C2412_IISMOD_RCLK_768FS;
	break;

	default:
	return -EINVAL;
	}

	reg = readl(i2s->regs + S3C2412_IISMOD);
	reg &= ~S3C2412_IISMOD_RCLK_MASK;
	writel(reg \| div, i2s->regs + S3C2412_IISMOD);
	pr_debug("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
	break;

	case S3C_I2SV2_DIV_PRESCALER:
	if (div >= 0) {
	writel((div << 8) \| S3C2412_IISPSR_PSREN,
	i2s->regs + S3C2412_IISPSR);
	} else {
	writel(0x0, i2s->regs + S3C2412_IISPSR);
	}
	pr_debug("%s: PSR=%08x\n", __func__, readl(i2s->regs + S3C2412_IISPSR));
	break;

	default:
	return -EINVAL;
	}

	return 0;
	}

	static snd_pcm_sframes_t s3c2412_i2s_delay(struct snd_pcm_substream *substream,
	struct snd_soc_dai *dai)
	{
	struct s3c_i2sv2_info *i2s = to_info(dai);
	u32 reg = readl(i2s->regs + S3C2412_IISFIC);
	snd_pcm_sframes_t delay;

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
	delay = S3C2412_IISFIC_TXCOUNT(reg);
	else
	delay = S3C2412_IISFIC_RXCOUNT(reg);

	return delay;
	}

	struct clk s3c_i2sv2_get_clock(struct snd_soc_dai cpu_dai)
	{
	struct s3c_i2sv2_info *i2s = to_info(cpu_dai);
	u32 iismod = readl(i2s->regs + S3C2412_IISMOD);

	if (iismod & S3C2412_IISMOD_IMS_SYSMUX)
	return i2s->iis_cclk;
	else
	return i2s->iis_pclk;
	}
	EXPORT_SYMBOL_GPL(s3c_i2sv2_get_clock);

	/* default table of all avaialable root fs divisors */
	static unsigned int iis_fs_tab[] = { 256, 512, 384, 768 };

	int s3c_i2sv2_iis_calc_rate(struct s3c_i2sv2_rate_calc *info,
	unsigned int *fstab,
	unsigned int rate, struct clk *clk)
	{
	unsigned long clkrate = clk_get_rate(clk);
	unsigned int div;
	unsigned int fsclk;
	unsigned int actual;
	unsigned int fs;
	unsigned int fsdiv;
	signed int deviation = 0;
	unsigned int best_fs = 0;
	unsigned int best_div = 0;
	unsigned int best_rate = 0;
	unsigned int best_deviation = INT_MAX;

	pr_debug("Input clock rate %ldHz\n", clkrate);

	if (fstab == NULL)
	fstab = iis_fs_tab;

	for (fs = 0; fs < ARRAY_SIZE(iis_fs_tab); fs++) {
	fsdiv = iis_fs_tab[fs];

	fsclk = clkrate / fsdiv;
	div = fsclk / rate;

	if ((fsclk % rate) > (rate / 2))
	div++;

	if (div <= 1)
	continue;

	actual = clkrate / (fsdiv * div);
	deviation = actual - rate;

	printk(KERN_DEBUG "%ufs: div %u => result %u, deviation %d\n",
	fsdiv, div, actual, deviation);

	deviation = abs(deviation);

	if (deviation < best_deviation) {
	best_fs = fsdiv;
	best_div = div;
	best_rate = actual;
	best_deviation = deviation;
	}

	if (deviation == 0)
	break;
	}

	printk(KERN_DEBUG "best: fs=%u, div=%u, rate=%u\n",
	best_fs, best_div, best_rate);

	info->fs_div = best_fs;
	info->clk_div = best_div;

	return 0;
	}
	EXPORT_SYMBOL_GPL(s3c_i2sv2_iis_calc_rate);

	int s3c_i2sv2_probe(struct snd_soc_dai *dai,
	struct s3c_i2sv2_info *i2s,
	unsigned long base)
	{
	struct device *dev = dai->dev;
	unsigned int iismod;

	i2s->dev = dev;

	/* record our i2s structure for later use in the callbacks */
	snd_soc_dai_set_drvdata(dai, i2s);

	i2s->regs = ioremap(base, 0x100);
	if (i2s->regs == NULL) {
	dev_err(dev, "cannot ioremap registers\n");
	return -ENXIO;
	}

	i2s->iis_pclk = clk_get(dev, "iis");
	if (IS_ERR(i2s->iis_pclk)) {
	dev_err(dev, "failed to get iis_clock\n");
	iounmap(i2s->regs);
	return -ENOENT;
	}

	clk_enable(i2s->iis_pclk);

	/* Mark ourselves as in TXRX mode so we can run through our cleanup
	* process without warnings. */
	iismod = readl(i2s->regs + S3C2412_IISMOD);
	iismod \|= S3C2412_IISMOD_MODE_TXRX;
	writel(iismod, i2s->regs + S3C2412_IISMOD);
	s3c2412_snd_txctrl(i2s, 0);
	s3c2412_snd_rxctrl(i2s, 0);

	return 0;
	}
	EXPORT_SYMBOL_GPL(s3c_i2sv2_probe);

	#ifdef CONFIG_PM
	static int s3c2412_i2s_suspend(struct snd_soc_dai *dai)
	{
	struct s3c_i2sv2_info *i2s = to_info(dai);
	u32 iismod;

	if (dai->active) {
	i2s->suspend_iismod = readl(i2s->regs + S3C2412_IISMOD);
	i2s->suspend_iiscon = readl(i2s->regs + S3C2412_IISCON);
	i2s->suspend_iispsr = readl(i2s->regs + S3C2412_IISPSR);

	/* some basic suspend checks */

	iismod = readl(i2s->regs + S3C2412_IISMOD);

	if (iismod & S3C2412_IISCON_RXDMA_ACTIVE)
	pr_warning("%s: RXDMA active?\n", __func__);

	if (iismod & S3C2412_IISCON_TXDMA_ACTIVE)
	pr_warning("%s: TXDMA active?\n", __func__);

	if (iismod & S3C2412_IISCON_IIS_ACTIVE)
	pr_warning("%s: IIS active\n", __func__);
	}

	return 0;
	}

	static int s3c2412_i2s_resume(struct snd_soc_dai *dai)
	{
	struct s3c_i2sv2_info *i2s = to_info(dai);

	pr_info("dai_active %d, IISMOD %08x, IISCON %08x\n",
	dai->active, i2s->suspend_iismod, i2s->suspend_iiscon);

	if (dai->active) {
	writel(i2s->suspend_iiscon, i2s->regs + S3C2412_IISCON);
	writel(i2s->suspend_iismod, i2s->regs + S3C2412_IISMOD);
	writel(i2s->suspend_iispsr, i2s->regs + S3C2412_IISPSR);

	writel(S3C2412_IISFIC_RXFLUSH \| S3C2412_IISFIC_TXFLUSH,
	i2s->regs + S3C2412_IISFIC);

	ndelay(250);
	writel(0x0, i2s->regs + S3C2412_IISFIC);
	}

	return 0;
	}
	#else
	#define s3c2412_i2s_suspend NULL
	#define s3c2412_i2s_resume NULL
	#endif

	int s3c_i2sv2_register_component(struct device *dev, int id,
	struct snd_soc_component_driver *cmp_drv,
	struct snd_soc_dai_driver *dai_drv)
	{
	struct snd_soc_dai_ops *ops = dai_drv->ops;

	ops->trigger = s3c2412_i2s_trigger;
	if (!ops->hw_params)
	ops->hw_params = s3c_i2sv2_hw_params;
	ops->set_fmt = s3c2412_i2s_set_fmt;
	ops->set_clkdiv = s3c2412_i2s_set_clkdiv;
	ops->set_sysclk = s3c_i2sv2_set_sysclk;

	/* Allow overriding by (for example) IISv4 */
	if (!ops->delay)
	ops->delay = s3c2412_i2s_delay;

	dai_drv->suspend = s3c2412_i2s_suspend;
	dai_drv->resume = s3c2412_i2s_resume;

	return snd_soc_register_component(dev, cmp_drv, dai_drv, 1);
	}
	EXPORT_SYMBOL_GPL(s3c_i2sv2_register_component);

	MODULE_LICENSE("GPL");