txx9aclc-ac97.c

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/*
 * TXx9 ACLC AC97 driver
 *
 * Copyright (C) 2009 Atsushi Nemoto
 *
 * Based on RBTX49xx patch from CELF patch archive.
 * (C) Copyright TOSHIBA CORPORATION 2004-2006
 *
 * 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.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/gfp.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/soc.h>
#include "txx9aclc.h"

#define AC97_DIR    \
    (SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)

#define AC97_RATES  \
    SNDRV_PCM_RATE_8000_48000

#ifdef __BIG_ENDIAN
#define AC97_FMTS   SNDRV_PCM_FMTBIT_S16_BE
#else
#define AC97_FMTS   SNDRV_PCM_FMTBIT_S16_LE
#endif

static DECLARE_WAIT_QUEUE_HEAD(ac97_waitq);

/* REVISIT: How to find txx9aclc_drvdata from snd_ac97? */
static struct txx9aclc_plat_drvdata *txx9aclc_drvdata;

static int txx9aclc_regready(struct txx9aclc_plat_drvdata *drvdata)
{
    return __raw_readl(drvdata->base + ACINTSTS) & ACINT_REGACCRDY;
}

/* AC97 controller reads codec register */
static unsigned short txx9aclc_ac97_read(struct snd_ac97 *ac97,
                     unsigned short reg)
{
    struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
    void __iomem *base = drvdata->base;
    u32 dat;

    if (!(__raw_readl(base + ACINTSTS) & ACINT_CODECRDY(ac97->num)))
        return 0xffff;
    reg |= ac97->num << 7;
    dat = (reg << ACREGACC_REG_SHIFT) | ACREGACC_READ;
    __raw_writel(dat, base + ACREGACC);
    __raw_writel(ACINT_REGACCRDY, base + ACINTEN);
    if (!wait_event_timeout(ac97_waitq, txx9aclc_regready(txx9aclc_drvdata), HZ)) {
        __raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
        printk(KERN_ERR "ac97 read timeout (reg %#x)\n", reg);
        dat = 0xffff;
        goto done;
    }
    dat = __raw_readl(base + ACREGACC);
    if (((dat >> ACREGACC_REG_SHIFT) & 0xff) != reg) {
        printk(KERN_ERR "reg mismatch %x with %x\n",
            dat, reg);
        dat = 0xffff;
        goto done;
    }
    dat = (dat >> ACREGACC_DAT_SHIFT) & 0xffff;
done:
    __raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
    return dat;
}

/* AC97 controller writes to codec register */
static void txx9aclc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
                unsigned short val)
{
    struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
    void __iomem *base = drvdata->base;

    __raw_writel(((reg | (ac97->num << 7)) << ACREGACC_REG_SHIFT) |
             (val << ACREGACC_DAT_SHIFT),
             base + ACREGACC);
    __raw_writel(ACINT_REGACCRDY, base + ACINTEN);
    if (!wait_event_timeout(ac97_waitq, txx9aclc_regready(txx9aclc_drvdata), HZ)) {
        printk(KERN_ERR
            "ac97 write timeout (reg %#x)\n", reg);
    }
    __raw_writel(ACINT_REGACCRDY, base + ACINTDIS);
}

static void txx9aclc_ac97_cold_reset(struct snd_ac97 *ac97)
{
    struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
    void __iomem *base = drvdata->base;
    u32 ready = ACINT_CODECRDY(ac97->num) | ACINT_REGACCRDY;

    __raw_writel(ACCTL_ENLINK, base + ACCTLDIS);
    mmiowb();
    udelay(1);
    __raw_writel(ACCTL_ENLINK, base + ACCTLEN);
    /* wait for primary codec ready status */
    __raw_writel(ready, base + ACINTEN);
    if (!wait_event_timeout(ac97_waitq,
                (__raw_readl(base + ACINTSTS) & ready) == ready,
                HZ)) {
        dev_err(&ac97->dev, "primary codec is not ready "
            "(status %#x)\n",
            __raw_readl(base + ACINTSTS));
    }
    __raw_writel(ACINT_REGACCRDY, base + ACINTSTS);
    __raw_writel(ready, base + ACINTDIS);
}

/* AC97 controller operations */
struct snd_ac97_bus_ops soc_ac97_ops = {
    .read       = txx9aclc_ac97_read,
    .write      = txx9aclc_ac97_write,
    .reset      = txx9aclc_ac97_cold_reset,
};
EXPORT_SYMBOL_GPL(soc_ac97_ops);

static irqreturn_t txx9aclc_ac97_irq(int irq, void *dev_id)
{
    struct txx9aclc_plat_drvdata *drvdata = dev_id;
    void __iomem *base = drvdata->base;

    __raw_writel(__raw_readl(base + ACINTMSTS), base + ACINTDIS);
    wake_up(&ac97_waitq);
    return IRQ_HANDLED;
}

static int txx9aclc_ac97_probe(struct snd_soc_dai *dai)
{
    txx9aclc_drvdata = snd_soc_dai_get_drvdata(dai);
    return 0;
}

static int txx9aclc_ac97_remove(struct snd_soc_dai *dai)
{
    struct txx9aclc_plat_drvdata *drvdata = snd_soc_dai_get_drvdata(dai);

    /* disable AC-link */
    __raw_writel(ACCTL_ENLINK, drvdata->base + ACCTLDIS);
    txx9aclc_drvdata = NULL;
    return 0;
}

static struct snd_soc_dai_driver txx9aclc_ac97_dai = {
    .ac97_control       = 1,
    .probe          = txx9aclc_ac97_probe,
    .remove         = txx9aclc_ac97_remove,
    .playback = {
        .rates      = AC97_RATES,
        .formats    = AC97_FMTS,
        .channels_min   = 2,
        .channels_max   = 2,
    },
    .capture = {
        .rates      = AC97_RATES,
        .formats    = AC97_FMTS,
        .channels_min   = 2,
        .channels_max   = 2,
    },
};

static int __devinit txx9aclc_ac97_dev_probe(struct platform_device *pdev)
{
    struct txx9aclc_plat_drvdata *drvdata;
    struct resource *r;
    int err;
    int irq;

    irq = platform_get_irq(pdev, 0);
    if (irq < 0)
        return irq;
    r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!r)
        return -EBUSY;

    if (!devm_request_mem_region(&pdev->dev, r->start, resource_size(r),
                     dev_name(&pdev->dev)))
        return -EBUSY;

    drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
    if (!drvdata)
        return -ENOMEM;
    platform_set_drvdata(pdev, drvdata);
    drvdata->physbase = r->start;
    if (sizeof(drvdata->physbase) > sizeof(r->start) &&
        r->start >= TXX9_DIRECTMAP_BASE &&
        r->start < TXX9_DIRECTMAP_BASE + 0x400000)
        drvdata->physbase |= 0xf00000000ull;
    drvdata->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
    if (!drvdata->base)
        return -EBUSY;
    err = devm_request_irq(&pdev->dev, irq, txx9aclc_ac97_irq,
                   0, dev_name(&pdev->dev), drvdata);
    if (err < 0)
        return err;

    return snd_soc_register_dai(&pdev->dev, &txx9aclc_ac97_dai);
}

static int __devexit txx9aclc_ac97_dev_remove(struct platform_device *pdev)
{
    snd_soc_unregister_dai(&pdev->dev);
    return 0;
}

static struct platform_driver txx9aclc_ac97_driver = {
    .probe      = txx9aclc_ac97_dev_probe,
    .remove     = __devexit_p(txx9aclc_ac97_dev_remove),
    .driver     = {
        .name   = "txx9aclc-ac97",
        .owner  = THIS_MODULE,
    },
};

module_platform_driver(txx9aclc_ac97_driver);

MODULE_AUTHOR("Atsushi Nemoto <[email protected]>");
MODULE_DESCRIPTION("TXx9 ACLC AC97 driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:txx9aclc-ac97");