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root/sound/soc/s3c24xx/s3c2412-i2s.c

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DEFINITIONS

This source file includes following definitions.
  1. dbg_showcon
  2. dbg_showcon
  3. s3c2412_snd_txctrl
  4. s3c2412_snd_rxctrl
  5. s3c2412_snd_lrsync
  6. s3c2412_snd_is_clkmaster
  7. s3c2412_i2s_set_fmt
  8. s3c2412_i2s_hw_params
  9. s3c2412_i2s_trigger
  10. s3c2412_iis_calc_rate
  11. s3c2412_i2s_set_sysclk
  12. s3c2412_i2s_set_clkdiv
  13. s3c2412_get_iisclk
  14. s3c2412_i2s_probe
  15. s3c2412_i2s_suspend
  16. s3c2412_i2s_resume

/* sound/soc/s3c24xx/s3c2412-i2s.c
 *
 * ALSA Soc Audio Layer - S3C2412 I2S driver
 *
 * Copyright (c) 2006 Wolfson Microelectronics PLC.
 *      Graeme Gregory graeme.gregory@wolfsonmicro.com
 *      linux@wolfsonmicro.com
 *
 * Copyright (c) 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/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/kernel.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <sound/soc.h>
#include <mach/hardware.h>

#include <linux/io.h>
#include <asm/dma.h>

#include <asm/plat-s3c24xx/regs-s3c2412-iis.h>

#include <mach/regs-gpio.h>
#include <mach/audio.h>
#include <mach/dma.h>

#include "s3c24xx-pcm.h"
#include "s3c2412-i2s.h"

#define S3C2412_I2S_DEBUG 0
#define S3C2412_I2S_DEBUG_CON 0

#if S3C2412_I2S_DEBUG
#define DBG(x...) printk(KERN_INFO x)
#else
#define DBG(x...) do { } while (0)
#endif

static struct s3c2410_dma_client s3c2412_dma_client_out = {
        .name           = "I2S PCM Stereo out"
};

static struct s3c2410_dma_client s3c2412_dma_client_in = {
        .name           = "I2S PCM Stereo in"
};

static struct s3c24xx_pcm_dma_params s3c2412_i2s_pcm_stereo_out = {
        .client         = &s3c2412_dma_client_out,
        .channel        = DMACH_I2S_OUT,
        .dma_addr       = S3C2410_PA_IIS + S3C2412_IISTXD,
        .dma_size       = 4,
};

static struct s3c24xx_pcm_dma_params s3c2412_i2s_pcm_stereo_in = {
        .client         = &s3c2412_dma_client_in,
        .channel        = DMACH_I2S_IN,
        .dma_addr       = S3C2410_PA_IIS + S3C2412_IISRXD,
        .dma_size       = 4,
};

struct s3c2412_i2s_info {
        struct device   *dev;
        void __iomem    *regs;
        struct clk      *iis_clk;
        struct clk      *iis_pclk;
        struct clk      *iis_cclk;

        u32              suspend_iismod;
        u32              suspend_iiscon;
        u32              suspend_iispsr;
};

static struct s3c2412_i2s_info s3c2412_i2s;

#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(int on)
{
        struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
        void __iomem *regs = i2s->regs;
        u32 fic, con, mod;

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

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

        DBG("%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 in IISMOD\n");
                }

                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 in IISMOD\n");
                }

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

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

static void s3c2412_snd_rxctrl(int on)
{
        struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
        void __iomem *regs = i2s->regs;
        u32 fic, con, mod;

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

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

        DBG("%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 in IISMOD\n");
                }

                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, "RXEN: Invalid MODE in IISMOD\n");
                }

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

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


/*
 * 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(void)
{
        u32 iiscon;
        unsigned long timeout = jiffies + msecs_to_jiffies(5);

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

        while (1) {
                iiscon = readl(s3c2412_i2s.regs + S3C2412_IISCON);
                if (iiscon & S3C2412_IISCON_LRINDEX)
                        break;

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

        return 0;
}

/*
 * Check whether CPU is the master or slave
 */
static inline int s3c2412_snd_is_clkmaster(void)
{
        u32 iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);

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

        iismod &= S3C2412_IISMOD_MASTER_MASK;
        return !(iismod == S3C2412_IISMOD_SLAVE);
}

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


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

        iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
        DBG("hw_params r: IISMOD: %x \n", iismod);

        switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
        case SND_SOC_DAIFMT_CBM_CFM:
                iismod &= ~S3C2412_IISMOD_MASTER_MASK;
                iismod |= S3C2412_IISMOD_SLAVE;
                break;
        case SND_SOC_DAIFMT_CBS_CFS:
                iismod &= ~S3C2412_IISMOD_MASTER_MASK;
                iismod |= S3C2412_IISMOD_MASTER_INTERNAL;
                break;
        default:
                DBG("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_SDF_MSB;
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                iismod |= S3C2412_IISMOD_SDF_LSB;
                break;
        case SND_SOC_DAIFMT_I2S:
                iismod |= S3C2412_IISMOD_SDF_IIS;
                break;
        default:
                DBG("Unknown data format\n");
                return -EINVAL;
        }

        writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
        DBG("hw_params w: IISMOD: %x \n", iismod);
        return 0;
}

static int s3c2412_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", __func__);

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                rtd->dai->cpu_dai->dma_data = &s3c2412_i2s_pcm_stereo_out;
        else
                rtd->dai->cpu_dai->dma_data = &s3c2412_i2s_pcm_stereo_in;

        /* Working copies of register */
        iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);
        DBG("%s: r: IISMOD: %x\n", __func__, iismod);

        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S8:
                iismod |= S3C2412_IISMOD_8BIT;
                break;
        case SNDRV_PCM_FORMAT_S16_LE:
                iismod &= ~S3C2412_IISMOD_8BIT;
                break;
        }

        writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
        DBG("%s: w: IISMOD: %x\n", __func__, iismod);
        return 0;
}

static int s3c2412_i2s_trigger(struct snd_pcm_substream *substream, int cmd)
{
        int capture = (substream->stream == SNDRV_PCM_STREAM_CAPTURE);
        unsigned long irqs;
        int ret = 0;

        DBG("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,
                       s3c2412_i2s.regs + S3C2412_IISFIC);

                /* clear again, just in case */
                writel(0x0, s3c2412_i2s.regs + S3C2412_IISFIC);

        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                if (!s3c2412_snd_is_clkmaster()) {
                        ret = s3c2412_snd_lrsync();
                        if (ret)
                                goto exit_err;
                }

                local_irq_save(irqs);

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

                local_irq_restore(irqs);
                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(0);
                else
                        s3c2412_snd_txctrl(0);

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

exit_err:
        return ret;
}

/* default table of all avaialable root fs divisors */
static unsigned int s3c2412_iis_fs[] = { 256, 512, 384, 768, 0 };

int s3c2412_iis_calc_rate(struct s3c2412_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;


        if (fstab == NULL)
                fstab = s3c2412_iis_fs;

        for (fs = 0;; fs++) {
                fsdiv = s3c2412_iis_fs[fs];

                if (fsdiv == 0)
                        break;

                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 "%dfs: div %d => result %d, 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=%d, div=%d, rate=%d\n",
               best_fs, best_div, best_rate);

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

        return 0;
}
EXPORT_SYMBOL_GPL(s3c2412_iis_calc_rate);

/*
 * Set S3C2412 Clock source
 */
static int s3c2412_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
                                  int clk_id, unsigned int freq, int dir)
{
        u32 iismod = readl(s3c2412_i2s.regs + S3C2412_IISMOD);

        DBG("%s(%p, %d, %u, %d)\n", __func__, cpu_dai, clk_id,
            freq, dir);

        switch (clk_id) {
        case S3C2412_CLKSRC_PCLK:
                iismod &= ~S3C2412_IISMOD_MASTER_MASK;
                iismod |= S3C2412_IISMOD_MASTER_INTERNAL;
                break;
        case S3C2412_CLKSRC_I2SCLK:
                iismod &= ~S3C2412_IISMOD_MASTER_MASK;
                iismod |= S3C2412_IISMOD_MASTER_EXTERNAL;
                break;
        default:
                return -EINVAL;
        }

        writel(iismod, s3c2412_i2s.regs + S3C2412_IISMOD);
        return 0;
}

/*
 * Set S3C2412 Clock dividers
 */
static int s3c2412_i2s_set_clkdiv(struct snd_soc_dai *cpu_dai,
                                  int div_id, int div)
{
        struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
        u32 reg;

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

        switch (div_id) {
        case S3C2412_DIV_BCLK:
                reg = readl(i2s->regs + S3C2412_IISMOD);
                reg &= ~S3C2412_IISMOD_BCLK_MASK;
                writel(reg | div, i2s->regs + S3C2412_IISMOD);

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

        case S3C2412_DIV_RCLK:
                if (div > 3) {
                        /* convert value to bit field */

                        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(s3c2412_i2s.regs + S3C2412_IISMOD);
                reg &= ~S3C2412_IISMOD_RCLK_MASK;
                writel(reg | div, i2s->regs + S3C2412_IISMOD);
                DBG("%s: MOD=%08x\n", __func__, readl(i2s->regs + S3C2412_IISMOD));
                break;

        case S3C2412_DIV_PRESCALER:
                if (div >= 0) {
                        writel((div << 8) | S3C2412_IISPSR_PSREN,
                               i2s->regs + S3C2412_IISPSR);
                } else {
                        writel(0x0, i2s->regs + S3C2412_IISPSR);
                }
                DBG("%s: PSR=%08x\n", __func__, readl(i2s->regs + S3C2412_IISPSR));
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

struct clk *s3c2412_get_iisclk(void)
{
        return s3c2412_i2s.iis_clk;
}
EXPORT_SYMBOL_GPL(s3c2412_get_iisclk);


static int s3c2412_i2s_probe(struct platform_device *pdev,
                             struct snd_soc_dai *dai)
{
        DBG("Entered %s\n", __func__);

        s3c2412_i2s.dev = &pdev->dev;

        s3c2412_i2s.regs = ioremap(S3C2410_PA_IIS, 0x100);
        if (s3c2412_i2s.regs == NULL)
                return -ENXIO;

        s3c2412_i2s.iis_pclk = clk_get(&pdev->dev, "iis");
        if (s3c2412_i2s.iis_pclk == NULL) {
                DBG("failed to get iis_clock\n");
                iounmap(s3c2412_i2s.regs);
                return -ENODEV;
        }

        s3c2412_i2s.iis_cclk = clk_get(&pdev->dev, "i2sclk");
        if (s3c2412_i2s.iis_cclk == NULL) {
                DBG("failed to get i2sclk clock\n");
                iounmap(s3c2412_i2s.regs);
                return -ENODEV;
        }

        clk_set_parent(s3c2412_i2s.iis_cclk, clk_get(NULL, "mpll"));

        clk_enable(s3c2412_i2s.iis_pclk);
        clk_enable(s3c2412_i2s.iis_cclk);

        s3c2412_i2s.iis_clk = s3c2412_i2s.iis_pclk;

        /* 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);

        s3c2412_snd_txctrl(0);
        s3c2412_snd_rxctrl(0);

        return 0;
}

#ifdef CONFIG_PM
static int s3c2412_i2s_suspend(struct platform_device *dev,
                              struct snd_soc_dai *dai)
{
        struct s3c2412_i2s_info *i2s = &s3c2412_i2s;
        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)
                        dev_warn(&dev->dev, "%s: RXDMA active?\n", __func__);

                if (iismod & S3C2412_IISCON_TXDMA_ACTIVE)
                        dev_warn(&dev->dev, "%s: TXDMA active?\n", __func__);

                if (iismod & S3C2412_IISCON_IIS_ACTIVE)
                        dev_warn(&dev->dev, "%s: IIS active\n", __func__);
        }

        return 0;
}

static int s3c2412_i2s_resume(struct platform_device *pdev,
                              struct snd_soc_dai *dai)
{
        struct s3c2412_i2s_info *i2s = &s3c2412_i2s;

        dev_info(&pdev->dev, "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 /* CONFIG_PM */

#define S3C2412_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_dai s3c2412_i2s_dai = {
        .name   = "s3c2412-i2s",
        .id     = 0,
        .type   = SND_SOC_DAI_I2S,
        .probe  = s3c2412_i2s_probe,
        .suspend = s3c2412_i2s_suspend,
        .resume = s3c2412_i2s_resume,
        .playback = {
                .channels_min   = 2,
                .channels_max   = 2,
                .rates          = S3C2412_I2S_RATES,
                .formats        = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,
        },
        .capture = {
                .channels_min   = 2,
                .channels_max   = 2,
                .rates          = S3C2412_I2S_RATES,
                .formats        = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_LE,
        },
        .ops = {
                .trigger        = s3c2412_i2s_trigger,
                .hw_params      = s3c2412_i2s_hw_params,
        },
        .dai_ops = {
                .set_fmt        = s3c2412_i2s_set_fmt,
                .set_clkdiv     = s3c2412_i2s_set_clkdiv,
                .set_sysclk     = s3c2412_i2s_set_sysclk,
        },
};
EXPORT_SYMBOL_GPL(s3c2412_i2s_dai);

/* Module information */
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_DESCRIPTION("S3C2412 I2S SoC Interface");
MODULE_LICENSE("GPL");

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