nuc900-ac97.c

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/*
 * Copyright (c) 2009-2010 Nuvoton technology corporation.
 *
 * Wan ZongShun <[email protected]>
 *
 * 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;version 2 of the License.
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/suspend.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/initval.h>
#include <sound/soc.h>
#include <linux/clk.h>

#include <mach/mfp.h>

#include "nuc900-audio.h"

static DEFINE_MUTEX(ac97_mutex);
struct nuc900_audio *nuc900_ac97_data;

static int nuc900_checkready(void)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;

    if (!(AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS0) & CODEC_READY))
        return -EPERM;

    return 0;
}

/* AC97 controller reads codec register */
static unsigned short nuc900_ac97_read(struct snd_ac97 *ac97,
                    unsigned short reg)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    unsigned long timeout = 0x10000, val;

    mutex_lock(&ac97_mutex);

    val = nuc900_checkready();
    if (val) {
        dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");
        goto out;
    }

    /* set the R_WB bit and write register index */
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS1, R_WB | reg);

    /* set the valid frame bit and valid slots */
    val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
    val |= (VALID_FRAME | SLOT1_VALID);
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, val);

    udelay(100);

    /* polling the AC_R_FINISH */
    while (!(AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON) & AC_R_FINISH)
                                && timeout--)
        mdelay(1);

    if (!timeout) {
        dev_err(nuc900_audio->dev, "AC97 read register time out !\n");
        val = -EPERM;
        goto out;
    }

    val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0) ;
    val &= ~SLOT1_VALID;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, val);

    if (AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS1) >> 2 != reg) {
        dev_err(nuc900_audio->dev,
                "R_INDEX of REG_ACTL_ACIS1 not match!\n");
    }

    udelay(100);
    val = (AUDIO_READ(nuc900_audio->mmio + ACTL_ACIS2) & 0xFFFF);

out:
    mutex_unlock(&ac97_mutex);
    return val;
}

/* AC97 controller writes to codec register */
static void nuc900_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
                unsigned short val)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    unsigned long tmp, timeout = 0x10000;

    mutex_lock(&ac97_mutex);

    tmp = nuc900_checkready();
    if (tmp)
        dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");

    /* clear the R_WB bit and write register index */
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS1, reg);

    /* write register value */
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS2, val);

    /* set the valid frame bit and valid slots */
    tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
    tmp |= SLOT1_VALID | SLOT2_VALID | VALID_FRAME;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);

    udelay(100);

    /* polling the AC_W_FINISH */
    while ((AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON) & AC_W_FINISH)
                                && timeout--)
        mdelay(1);

    if (!timeout)
        dev_err(nuc900_audio->dev, "AC97 write register time out !\n");

    tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
    tmp &= ~(SLOT1_VALID | SLOT2_VALID);
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);

    mutex_unlock(&ac97_mutex);

}

static void nuc900_ac97_warm_reset(struct snd_ac97 *ac97)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    unsigned long val;

    mutex_lock(&ac97_mutex);

    /* warm reset AC 97 */
    val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
    val |= AC_W_RES;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);

    udelay(100);

    val = nuc900_checkready();
    if (val)
        dev_err(nuc900_audio->dev, "AC97 codec is not ready\n");

    mutex_unlock(&ac97_mutex);
}

static void nuc900_ac97_cold_reset(struct snd_ac97 *ac97)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    unsigned long val;

    mutex_lock(&ac97_mutex);

    /* reset Audio Controller */
    val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
    val |= ACTL_RESET_BIT;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

    val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
    val &= (~ACTL_RESET_BIT);
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

    /* reset AC-link interface */

    val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
    val |= AC_RESET;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

    val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
    val &= ~AC_RESET;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

    /* cold reset AC 97 */
    val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
    val |= AC_C_RES;
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);

    val = AUDIO_READ(nuc900_audio->mmio + ACTL_ACCON);
    val &= (~AC_C_RES);
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACCON, val);

    udelay(100);

    mutex_unlock(&ac97_mutex);

}

/* AC97 controller operations */
struct snd_ac97_bus_ops soc_ac97_ops = {
    .read       = nuc900_ac97_read,
    .write      = nuc900_ac97_write,
    .reset      = nuc900_ac97_cold_reset,
    .warm_reset = nuc900_ac97_warm_reset,
}
EXPORT_SYMBOL_GPL(soc_ac97_ops);

static int nuc900_ac97_trigger(struct snd_pcm_substream *substream,
                int cmd, struct snd_soc_dai *dai)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    int ret;
    unsigned long val, tmp;

    ret = 0;

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
    case SNDRV_PCM_TRIGGER_RESUME:
        val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
            tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
            tmp |= (SLOT3_VALID | SLOT4_VALID | VALID_FRAME);
            AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);

            tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_PSR);
            tmp |= (P_DMA_END_IRQ | P_DMA_MIDDLE_IRQ);
            AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, tmp);
            val |= AC_PLAY;
        } else {
            tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_RSR);
            tmp |= (R_DMA_END_IRQ | R_DMA_MIDDLE_IRQ);

            AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, tmp);
            val |= AC_RECORD;
        }

        AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

        break;
    case SNDRV_PCM_TRIGGER_STOP:
    case SNDRV_PCM_TRIGGER_SUSPEND:
        val = AUDIO_READ(nuc900_audio->mmio + ACTL_RESET);
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
            tmp = AUDIO_READ(nuc900_audio->mmio + ACTL_ACOS0);
            tmp &= ~(SLOT3_VALID | SLOT4_VALID);
            AUDIO_WRITE(nuc900_audio->mmio + ACTL_ACOS0, tmp);

            AUDIO_WRITE(nuc900_audio->mmio + ACTL_PSR, RESET_PRSR);
            val &= ~AC_PLAY;
        } else {
            AUDIO_WRITE(nuc900_audio->mmio + ACTL_RSR, RESET_PRSR);
            val &= ~AC_RECORD;
        }

        AUDIO_WRITE(nuc900_audio->mmio + ACTL_RESET, val);

        break;
    default:
        ret = -EINVAL;
    }

    return ret;
}

static int nuc900_ac97_probe(struct snd_soc_dai *dai)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;
    unsigned long val;

    mutex_lock(&ac97_mutex);

    /* enable unit clock */
    clk_enable(nuc900_audio->clk);

    /* enable audio controller and AC-link interface */
    val = AUDIO_READ(nuc900_audio->mmio + ACTL_CON);
    val |= (IIS_AC_PIN_SEL | ACLINK_EN);
    AUDIO_WRITE(nuc900_audio->mmio + ACTL_CON, val);

    mutex_unlock(&ac97_mutex);

    return 0;
}

static int nuc900_ac97_remove(struct snd_soc_dai *dai)
{
    struct nuc900_audio *nuc900_audio = nuc900_ac97_data;

    clk_disable(nuc900_audio->clk);
    return 0;
}

static const struct snd_soc_dai_ops nuc900_ac97_dai_ops = {
    .trigger    = nuc900_ac97_trigger,
};

static struct snd_soc_dai_driver nuc900_ac97_dai = {
    .probe          = nuc900_ac97_probe,
    .remove         = nuc900_ac97_remove,
    .ac97_control       = 1,
    .playback = {
        .rates      = SNDRV_PCM_RATE_8000_48000,
        .formats    = SNDRV_PCM_FMTBIT_S16_LE,
        .channels_min   = 1,
        .channels_max   = 2,
    },
    .capture = {
        .rates      = SNDRV_PCM_RATE_8000_48000,
        .formats    = SNDRV_PCM_FMTBIT_S16_LE,
        .channels_min   = 1,
        .channels_max   = 2,
    },
    .ops = &nuc900_ac97_dai_ops,
};

static int __devinit nuc900_ac97_drvprobe(struct platform_device *pdev)
{
    struct nuc900_audio *nuc900_audio;
    int ret;

    if (nuc900_ac97_data)
        return -EBUSY;

    nuc900_audio = kzalloc(sizeof(struct nuc900_audio), GFP_KERNEL);
    if (!nuc900_audio)
        return -ENOMEM;

    spin_lock_init(&nuc900_audio->lock);

    nuc900_audio->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!nuc900_audio->res) {
        ret = -ENODEV;
        goto out0;
    }

    if (!request_mem_region(nuc900_audio->res->start,
            resource_size(nuc900_audio->res), pdev->name)) {
        ret = -EBUSY;
        goto out0;
    }

    nuc900_audio->mmio = ioremap(nuc900_audio->res->start,
                    resource_size(nuc900_audio->res));
    if (!nuc900_audio->mmio) {
        ret = -ENOMEM;
        goto out1;
    }

    nuc900_audio->clk = clk_get(&pdev->dev, NULL);
    if (IS_ERR(nuc900_audio->clk)) {
        ret = PTR_ERR(nuc900_audio->clk);
        goto out2;
    }

    nuc900_audio->irq_num = platform_get_irq(pdev, 0);
    if (!nuc900_audio->irq_num) {
        ret = -EBUSY;
        goto out3;
    }

    nuc900_ac97_data = nuc900_audio;

    ret = snd_soc_register_dai(&pdev->dev, &nuc900_ac97_dai);
    if (ret)
        goto out3;

    /* enbale ac97 multifunction pin */
    mfp_set_groupg(nuc900_audio->dev, NULL);

    return 0;

out3:
    clk_put(nuc900_audio->clk);
out2:
    iounmap(nuc900_audio->mmio);
out1:
    release_mem_region(nuc900_audio->res->start,
                    resource_size(nuc900_audio->res));
out0:
    kfree(nuc900_audio);
    return ret;
}

static int __devexit nuc900_ac97_drvremove(struct platform_device *pdev)
{
    snd_soc_unregister_dai(&pdev->dev);

    clk_put(nuc900_ac97_data->clk);
    iounmap(nuc900_ac97_data->mmio);
    release_mem_region(nuc900_ac97_data->res->start,
                resource_size(nuc900_ac97_data->res));

    kfree(nuc900_ac97_data);
    nuc900_ac97_data = NULL;

    return 0;
}

static struct platform_driver nuc900_ac97_driver = {
    .driver = {
        .name   = "nuc900-ac97",
        .owner  = THIS_MODULE,
    },
    .probe      = nuc900_ac97_drvprobe,
    .remove     = __devexit_p(nuc900_ac97_drvremove),
};

module_platform_driver(nuc900_ac97_driver);

MODULE_AUTHOR("Wan ZongShun <[email protected]>");
MODULE_DESCRIPTION("NUC900 AC97 SoC driver!");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:nuc900-ac97");