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root/sound/soc/au1x/psc-i2s.c

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DEFINITIONS

This source file includes following definitions.
  1. au1xpsc_i2s_set_fmt
  2. au1xpsc_i2s_hw_params
  3. au1xpsc_i2s_configure
  4. au1xpsc_i2s_start
  5. au1xpsc_i2s_stop
  6. au1xpsc_i2s_trigger
  7. au1xpsc_i2s_probe
  8. au1xpsc_i2s_remove
  9. au1xpsc_i2s_suspend
  10. au1xpsc_i2s_resume
  11. au1xpsc_i2s_init
  12. au1xpsc_i2s_exit

/*
 * 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_TB | 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>");

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