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root/sound/soc/sh/hac.c

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DEFINITIONS

This source file includes following definitions.
  1. hac_get_codec_data
  2. hac_read_codec_aux
  3. hac_ac97_write
  4. hac_ac97_read
  5. hac_ac97_warmrst
  6. hac_ac97_coldrst
  7. hac_hw_params

/*
 * Hitachi Audio Controller (AC97) support for SH7760/SH7780
 *
 * Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net>
 *  licensed under the terms outlined in the file COPYING at the root
 *  of the linux kernel sources.
 *
 * dont forget to set IPSEL/OMSEL register bits (in your board code) to
 * enable HAC output pins!
 */

/* BIG FAT FIXME: although the SH7760 has 2 independent AC97 units, only
 * the FIRST can be used since ASoC does not pass any information to the
 * ac97_read/write() functions regarding WHICH unit to use.  You'll have
 * to edit the code a bit to use the other AC97 unit.           --mlau
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/ac97_codec.h>
#include <sound/initval.h>
#include <sound/soc.h>

/* regs and bits */
#define HACCR           0x08
#define HACCSAR         0x20
#define HACCSDR         0x24
#define HACPCML         0x28
#define HACPCMR         0x2C
#define HACTIER         0x50
#define HACTSR          0x54
#define HACRIER         0x58
#define HACRSR          0x5C
#define HACACR          0x60

#define CR_CR           (1 << 15)       /* "codec-ready" indicator */
#define CR_CDRT         (1 << 11)       /* cold reset */
#define CR_WMRT         (1 << 10)       /* warm reset */
#define CR_B9           (1 << 9)        /* the mysterious "bit 9" */
#define CR_ST           (1 << 5)        /* AC97 link start bit */

#define CSAR_RD         (1 << 19)       /* AC97 data read bit */
#define CSAR_WR         (0)

#define TSR_CMDAMT      (1 << 31)
#define TSR_CMDDMT      (1 << 30)

#define RSR_STARY       (1 << 22)
#define RSR_STDRY       (1 << 21)

#define ACR_DMARX16     (1 << 30)
#define ACR_DMATX16     (1 << 29)
#define ACR_TX12ATOM    (1 << 26)
#define ACR_DMARX20     ((1 << 24) | (1 << 22))
#define ACR_DMATX20     ((1 << 23) | (1 << 21))

#define CSDR_SHIFT      4
#define CSDR_MASK       (0xffff << CSDR_SHIFT)
#define CSAR_SHIFT      12
#define CSAR_MASK       (0x7f << CSAR_SHIFT)

#define AC97_WRITE_RETRY        1
#define AC97_READ_RETRY         5

/* manual-suggested AC97 codec access timeouts (us) */
#define TMO_E1  500     /* 21 < E1 < 1000 */
#define TMO_E2  13      /* 13 < E2 */
#define TMO_E3  21      /* 21 < E3 */
#define TMO_E4  500     /* 21 < E4 < 1000 */

struct hac_priv {
        unsigned long mmio;     /* HAC base address */
} hac_cpu_data[] = {
#if defined(CONFIG_CPU_SUBTYPE_SH7760)
        {
                .mmio   = 0xFE240000,
        },
        {
                .mmio   = 0xFE250000,
        },
#elif defined(CONFIG_CPU_SUBTYPE_SH7780)
        {
                .mmio   = 0xFFE40000,
        },
#else
#error "Unsupported SuperH SoC"
#endif
};

#define HACREG(reg)     (*(unsigned long *)(hac->mmio + (reg)))

/*
 * AC97 read/write flow as outlined in the SH7760 manual (pages 903-906)
 */
static int hac_get_codec_data(struct hac_priv *hac, unsigned short r,
                              unsigned short *v)
{
        unsigned int to1, to2, i;
        unsigned short adr;

        for (i = AC97_READ_RETRY; i; i--) {
                *v = 0;
                /* wait for HAC to receive something from the codec */
                for (to1 = TMO_E4;
                     to1 && !(HACREG(HACRSR) & RSR_STARY);
                     --to1)
                        udelay(1);
                for (to2 = TMO_E4; 
                     to2 && !(HACREG(HACRSR) & RSR_STDRY);
                     --to2)
                        udelay(1);

                if (!to1 && !to2)
                        return 0;       /* codec comm is down */

                adr = ((HACREG(HACCSAR) & CSAR_MASK) >> CSAR_SHIFT);
                *v  = ((HACREG(HACCSDR) & CSDR_MASK) >> CSDR_SHIFT);

                HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);

                if (r == adr)
                        break;

                /* manual says: wait at least 21 usec before retrying */
                udelay(21);
        }
        HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
        return i;
}

static unsigned short hac_read_codec_aux(struct hac_priv *hac,
                                         unsigned short reg)
{
        unsigned short val;
        unsigned int i, to;

        for (i = AC97_READ_RETRY; i; i--) {
                /* send_read_request */
                local_irq_disable();
                HACREG(HACTSR) &= ~(TSR_CMDAMT);
                HACREG(HACCSAR) = (reg << CSAR_SHIFT) | CSAR_RD;
                local_irq_enable();

                for (to = TMO_E3;
                     to && !(HACREG(HACTSR) & TSR_CMDAMT);
                     --to)
                        udelay(1);

                HACREG(HACTSR) &= ~TSR_CMDAMT;
                val = 0;
                if (hac_get_codec_data(hac, reg, &val) != 0)
                        break;
        }

        return i ? val : ~0;
}

static void hac_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
                           unsigned short val)
{
        int unit_id = 0 /* ac97->private_data */;
        struct hac_priv *hac = &hac_cpu_data[unit_id];
        unsigned int i, to;
        /* write_codec_aux */
        for (i = AC97_WRITE_RETRY; i; i--) {
                /* send_write_request */
                local_irq_disable();
                HACREG(HACTSR) &= ~(TSR_CMDDMT | TSR_CMDAMT);
                HACREG(HACCSDR) = (val << CSDR_SHIFT);
                HACREG(HACCSAR) = (reg << CSAR_SHIFT) & (~CSAR_RD);
                local_irq_enable();

                /* poll-wait for CMDAMT and CMDDMT */
                for (to = TMO_E1;
                     to && !(HACREG(HACTSR) & (TSR_CMDAMT|TSR_CMDDMT));
                     --to)
                        udelay(1);

                HACREG(HACTSR) &= ~(TSR_CMDAMT | TSR_CMDDMT);
                if (to)
                        break;
                /* timeout, try again */
        }
}

static unsigned short hac_ac97_read(struct snd_ac97 *ac97,
                                    unsigned short reg)
{
        int unit_id = 0 /* ac97->private_data */;
        struct hac_priv *hac = &hac_cpu_data[unit_id];
        return hac_read_codec_aux(hac, reg);
}

static void hac_ac97_warmrst(struct snd_ac97 *ac97)
{
        int unit_id = 0 /* ac97->private_data */;
        struct hac_priv *hac = &hac_cpu_data[unit_id];
        unsigned int tmo;

        HACREG(HACCR) = CR_WMRT | CR_ST | CR_B9;
        msleep(10);
        HACREG(HACCR) = CR_ST | CR_B9;
        for (tmo = 1000; (tmo > 0) && !(HACREG(HACCR) & CR_CR); tmo--)
                udelay(1);

        if (!tmo)
                printk(KERN_INFO "hac: reset: AC97 link down!\n");
        /* settings this bit lets us have a conversation with codec */
        HACREG(HACACR) |= ACR_TX12ATOM;
}

static void hac_ac97_coldrst(struct snd_ac97 *ac97)
{
        int unit_id = 0 /* ac97->private_data */;
        struct hac_priv *hac;
        hac = &hac_cpu_data[unit_id];

        HACREG(HACCR) = 0;
        HACREG(HACCR) = CR_CDRT | CR_ST | CR_B9;
        msleep(10);
        hac_ac97_warmrst(ac97);
}

struct snd_ac97_bus_ops soc_ac97_ops = {
        .read   = hac_ac97_read,
        .write  = hac_ac97_write,
        .reset  = hac_ac97_coldrst,
        .warm_reset = hac_ac97_warmrst,
};
EXPORT_SYMBOL_GPL(soc_ac97_ops);

static int hac_hw_params(struct snd_pcm_substream *substream,
                         struct snd_pcm_hw_params *params)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct hac_priv *hac = &hac_cpu_data[rtd->dai->cpu_dai->id];
        int d = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1;

        switch (params->msbits) {
        case 16:
                HACREG(HACACR) |= d ?  ACR_DMARX16 :  ACR_DMATX16;
                HACREG(HACACR) &= d ? ~ACR_DMARX20 : ~ACR_DMATX20;
                break;
        case 20:
                HACREG(HACACR) &= d ? ~ACR_DMARX16 : ~ACR_DMATX16;
                HACREG(HACACR) |= d ?  ACR_DMARX20 :  ACR_DMATX20;
                break;
        default:
                pr_debug("hac: invalid depth %d bit\n", params->msbits);
                return -EINVAL;
                break;
        }

        return 0;
}

#define AC97_RATES      \
        SNDRV_PCM_RATE_8000_192000

#define AC97_FMTS       \
        SNDRV_PCM_FMTBIT_S16_LE

struct snd_soc_dai sh4_hac_dai[] = {
{
        .name                   = "HAC0",
        .id                     = 0,
        .type                   = SND_SOC_DAI_AC97,
        .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 = {
                .hw_params      = hac_hw_params,
        },
},
#ifdef CONFIG_CPU_SUBTYPE_SH7760
{
        .name                   = "HAC1",
        .id                     = 1,
        .type                   = SND_SOC_DAI_AC97,
        .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 = {
                .hw_params      = hac_hw_params,
        },

},
#endif
};
EXPORT_SYMBOL_GPL(sh4_hac_dai);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SuperH onchip HAC (AC97) audio driver");
MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");

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