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root/sound/soc/au1x/psc-ac97.c

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DEFINITIONS

This source file includes following definitions.
  1. au1xpsc_ac97_read
  2. au1xpsc_ac97_write
  3. au1xpsc_ac97_warm_reset
  4. au1xpsc_ac97_cold_reset
  5. au1xpsc_ac97_hw_params
  6. au1xpsc_ac97_trigger
  7. au1xpsc_ac97_probe
  8. au1xpsc_ac97_remove
  9. au1xpsc_ac97_suspend
  10. au1xpsc_ac97_resume
  11. au1xpsc_ac97_init
  12. au1xpsc_ac97_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 AC97 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.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/delay.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"

#define AC97_DIR        \
        (SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)

#define AC97_RATES      \
        SNDRV_PCM_RATE_8000_48000

#define AC97_FMTS       \
        (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3BE)

#define AC97PCR_START(stype)    \
        ((stype) == PCM_TX ? PSC_AC97PCR_TS : PSC_AC97PCR_RS)
#define AC97PCR_STOP(stype)     \
        ((stype) == PCM_TX ? PSC_AC97PCR_TP : PSC_AC97PCR_RP)
#define AC97PCR_CLRFIFO(stype)  \
        ((stype) == PCM_TX ? PSC_AC97PCR_TC : PSC_AC97PCR_RC)

/* instance data. There can be only one, MacLeod!!!! */
static struct au1xpsc_audio_data *au1xpsc_ac97_workdata;

/* AC97 controller reads codec register */
static unsigned short au1xpsc_ac97_read(struct snd_ac97 *ac97,
                                        unsigned short reg)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
        unsigned short data, tmo;

        au_writel(PSC_AC97CDC_RD | PSC_AC97CDC_INDX(reg), AC97_CDC(pscdata));
        au_sync();

        tmo = 1000;
        while ((!(au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)) && --tmo)
                udelay(2);

        if (!tmo)
                data = 0xffff;
        else
                data = au_readl(AC97_CDC(pscdata)) & 0xffff;

        au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
        au_sync();

        return data;
}

/* AC97 controller writes to codec register */
static void au1xpsc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
                                unsigned short val)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
        unsigned int tmo;

        au_writel(PSC_AC97CDC_INDX(reg) | (val & 0xffff), AC97_CDC(pscdata));
        au_sync();
        tmo = 1000;
        while ((!(au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)) && --tmo)
                au_sync();

        au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
        au_sync();
}

/* AC97 controller asserts a warm reset */
static void au1xpsc_ac97_warm_reset(struct snd_ac97 *ac97)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;

        au_writel(PSC_AC97RST_SNC, AC97_RST(pscdata));
        au_sync();
        msleep(10);
        au_writel(0, AC97_RST(pscdata));
        au_sync();
}

static void au1xpsc_ac97_cold_reset(struct snd_ac97 *ac97)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
        int i;

        /* disable PSC during cold reset */
        au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
        au_sync();
        au_writel(PSC_CTRL_DISABLE, PSC_CTRL(pscdata));
        au_sync();

        /* issue cold reset */
        au_writel(PSC_AC97RST_RST, AC97_RST(pscdata));
        au_sync();
        msleep(500);
        au_writel(0, AC97_RST(pscdata));
        au_sync();

        /* enable PSC */
        au_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
        au_sync();

        /* wait for PSC to indicate it's ready */
        i = 100000;
        while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_SR)) && (--i))
                au_sync();

        if (i == 0) {
                printk(KERN_ERR "au1xpsc-ac97: PSC not ready!\n");
                return;
        }

        /* enable the ac97 function */
        au_writel(pscdata->cfg | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
        au_sync();

        /* wait for AC97 core to become ready */
        i = 100000;
        while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && (--i))
                au_sync();
        if (i == 0)
                printk(KERN_ERR "au1xpsc-ac97: AC97 ctrl not ready\n");
}

/* AC97 controller operations */
struct snd_ac97_bus_ops soc_ac97_ops = {
        .read           = au1xpsc_ac97_read,
        .write          = au1xpsc_ac97_write,
        .reset          = au1xpsc_ac97_cold_reset,
        .warm_reset     = au1xpsc_ac97_warm_reset,
};
EXPORT_SYMBOL_GPL(soc_ac97_ops);

static int au1xpsc_ac97_hw_params(struct snd_pcm_substream *substream,
                                  struct snd_pcm_hw_params *params)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
        unsigned long r, stat;
        int chans, stype = SUBSTREAM_TYPE(substream);

        chans = params_channels(params);

        r = au_readl(AC97_CFG(pscdata));
        stat = au_readl(AC97_STAT(pscdata));

        /* already active? */
        if (stat & (PSC_AC97STAT_TB | PSC_AC97STAT_RB)) {
                /* reject parameters not currently set up */
                if ((PSC_AC97CFG_GET_LEN(r) != params->msbits) ||
                    (pscdata->rate != params_rate(params)))
                        return -EINVAL;
        } else {
                /* disable AC97 device controller first */
                au_writel(r & ~PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
                au_sync();

                /* set sample bitdepth: REG[24:21]=(BITS-2)/2 */
                r &= ~PSC_AC97CFG_LEN_MASK;
                r |= PSC_AC97CFG_SET_LEN(params->msbits);

                /* channels: enable slots for front L/R channel */
                if (stype == PCM_TX) {
                        r &= ~PSC_AC97CFG_TXSLOT_MASK;
                        r |= PSC_AC97CFG_TXSLOT_ENA(3);
                        r |= PSC_AC97CFG_TXSLOT_ENA(4);
                } else {
                        r &= ~PSC_AC97CFG_RXSLOT_MASK;
                        r |= PSC_AC97CFG_RXSLOT_ENA(3);
                        r |= PSC_AC97CFG_RXSLOT_ENA(4);
                }

                /* finally enable the AC97 controller again */
                au_writel(r | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
                au_sync();

                pscdata->cfg = r;
                pscdata->rate = params_rate(params);
        }

        return 0;
}

static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
                                int cmd)
{
        /* FIXME */
        struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
        int ret, stype = SUBSTREAM_TYPE(substream);

        ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
                au_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
                au_sync();
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                au_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
                au_sync();
                break;
        default:
                ret = -EINVAL;
        }
        return ret;
}

static int au1xpsc_ac97_probe(struct platform_device *pdev,
                              struct snd_soc_dai *dai)
{
        int ret;
        struct resource *r;
        unsigned long sel;

        if (au1xpsc_ac97_workdata)
                return -EBUSY;

        au1xpsc_ac97_workdata =
                kzalloc(sizeof(struct au1xpsc_audio_data), GFP_KERNEL);
        if (!au1xpsc_ac97_workdata)
                return -ENOMEM;

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

        ret = -EBUSY;
        au1xpsc_ac97_workdata->ioarea =
                request_mem_region(r->start, r->end - r->start + 1,
                                        "au1xpsc_ac97");
        if (!au1xpsc_ac97_workdata->ioarea)
                goto out0;

        au1xpsc_ac97_workdata->mmio = ioremap(r->start, 0xffff);
        if (!au1xpsc_ac97_workdata->mmio)
                goto out1;

        /* configuration: max dma trigger threshold, enable ac97 */
         au1xpsc_ac97_workdata->cfg = PSC_AC97CFG_RT_FIFO8 |
                                      PSC_AC97CFG_TT_FIFO8 |
                                      PSC_AC97CFG_DE_ENABLE;

        /* preserve PSC clock source set up by platform (dev.platform_data
         * is already occupied by soc layer)
         */
        sel = au_readl(PSC_SEL(au1xpsc_ac97_workdata)) & PSC_SEL_CLK_MASK;
        au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
        au_sync();
        au_writel(0, PSC_SEL(au1xpsc_ac97_workdata));
        au_sync();
        au_writel(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(au1xpsc_ac97_workdata));
        au_sync();
        /* next up: cold reset.  Dont check for PSC-ready now since
         * there may not be any codec clock yet.
         */

        return 0;

out1:
        release_resource(au1xpsc_ac97_workdata->ioarea);
        kfree(au1xpsc_ac97_workdata->ioarea);
out0:
        kfree(au1xpsc_ac97_workdata);
        au1xpsc_ac97_workdata = NULL;
        return ret;
}

static void au1xpsc_ac97_remove(struct platform_device *pdev,
                                struct snd_soc_dai *dai)
{
        /* disable PSC completely */
        au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
        au_sync();
        au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
        au_sync();

        iounmap(au1xpsc_ac97_workdata->mmio);
        release_resource(au1xpsc_ac97_workdata->ioarea);
        kfree(au1xpsc_ac97_workdata->ioarea);
        kfree(au1xpsc_ac97_workdata);
        au1xpsc_ac97_workdata = NULL;
}

static int au1xpsc_ac97_suspend(struct platform_device *pdev,
                                struct snd_soc_dai *dai)
{
        /* save interesting registers and disable PSC */
        au1xpsc_ac97_workdata->pm[0] =
                        au_readl(PSC_SEL(au1xpsc_ac97_workdata));

        au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
        au_sync();
        au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
        au_sync();

        return 0;
}

static int au1xpsc_ac97_resume(struct platform_device *pdev,
                               struct snd_soc_dai *dai)
{
        /* restore PSC clock config */
        au_writel(au1xpsc_ac97_workdata->pm[0] | PSC_SEL_PS_AC97MODE,
                        PSC_SEL(au1xpsc_ac97_workdata));
        au_sync();

        /* after this point the ac97 core will cold-reset the codec.
         * During cold-reset the PSC is reinitialized and the last
         * configuration set up in hw_params() is restored.
         */
        return 0;
}

struct snd_soc_dai au1xpsc_ac97_dai = {
        .name                   = "au1xpsc_ac97",
        .type                   = SND_SOC_DAI_AC97,
        .probe                  = au1xpsc_ac97_probe,
        .remove                 = au1xpsc_ac97_remove,
        .suspend                = au1xpsc_ac97_suspend,
        .resume                 = au1xpsc_ac97_resume,
        .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,
        },
        .ops = {
                .trigger        = au1xpsc_ac97_trigger,
                .hw_params      = au1xpsc_ac97_hw_params,
        },
};
EXPORT_SYMBOL_GPL(au1xpsc_ac97_dai);

static int __init au1xpsc_ac97_init(void)
{
        au1xpsc_ac97_workdata = NULL;
        return 0;
}

static void __exit au1xpsc_ac97_exit(void)
{
}

module_init(au1xpsc_ac97_init);
module_exit(au1xpsc_ac97_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");

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