ak4531_codec.c

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/*
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 *  Universal routines for AK4531 codec
 *
 *
 *   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; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/module.h>

#include <sound/core.h>
#include <sound/ak4531_codec.h>
#include <sound/tlv.h>

/*
MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
MODULE_DESCRIPTION("Universal routines for AK4531 codec");
MODULE_LICENSE("GPL");
*/

#ifdef CONFIG_PROC_FS
static void snd_ak4531_proc_init(struct snd_card *card, struct snd_ak4531 *ak4531);
#else
#define snd_ak4531_proc_init(card,ak)
#endif

/*
 *
 */
 
#if 0

static void snd_ak4531_dump(struct snd_ak4531 *ak4531)
{
    int idx;
    
    for (idx = 0; idx < 0x19; idx++)
        printk(KERN_DEBUG "ak4531 0x%x: 0x%x\n",
               idx, ak4531->regs[idx]);
}

#endif

/*
 *
 */

#define AK4531_SINGLE(xname, xindex, reg, shift, mask, invert) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_ak4531_info_single, \
  .get = snd_ak4531_get_single, .put = snd_ak4531_put_single, \
  .private_value = reg | (shift << 16) | (mask << 24) | (invert << 22) }
#define AK4531_SINGLE_TLV(xname, xindex, reg, shift, mask, invert, xtlv)    \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
  .name = xname, .index = xindex, \
  .info = snd_ak4531_info_single, \
  .get = snd_ak4531_get_single, .put = snd_ak4531_put_single, \
  .private_value = reg | (shift << 16) | (mask << 24) | (invert << 22), \
  .tlv = { .p = (xtlv) } }

static int snd_ak4531_info_single(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
    int mask = (kcontrol->private_value >> 24) & 0xff;

    uinfo->type = mask == 1 ? SNDRV_CTL_ELEM_TYPE_BOOLEAN : SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 1;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = mask;
    return 0;
}
 
static int snd_ak4531_get_single(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 16) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;
    int val;

    mutex_lock(&ak4531->reg_mutex);
    val = (ak4531->regs[reg] >> shift) & mask;
    mutex_unlock(&ak4531->reg_mutex);
    if (invert) {
        val = mask - val;
    }
    ucontrol->value.integer.value[0] = val;
    return 0;
}

static int snd_ak4531_put_single(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int reg = kcontrol->private_value & 0xff;
    int shift = (kcontrol->private_value >> 16) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;
    int change;
    int val;

    val = ucontrol->value.integer.value[0] & mask;
    if (invert) {
        val = mask - val;
    }
    val <<= shift;
    mutex_lock(&ak4531->reg_mutex);
    val = (ak4531->regs[reg] & ~(mask << shift)) | val;
    change = val != ak4531->regs[reg];
    ak4531->write(ak4531, reg, ak4531->regs[reg] = val);
    mutex_unlock(&ak4531->reg_mutex);
    return change;
}

#define AK4531_DOUBLE(xname, xindex, left_reg, right_reg, left_shift, right_shift, mask, invert) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_ak4531_info_double, \
  .get = snd_ak4531_get_double, .put = snd_ak4531_put_double, \
  .private_value = left_reg | (right_reg << 8) | (left_shift << 16) | (right_shift << 19) | (mask << 24) | (invert << 22) }
#define AK4531_DOUBLE_TLV(xname, xindex, left_reg, right_reg, left_shift, right_shift, mask, invert, xtlv) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
  .access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ, \
  .name = xname, .index = xindex, \
  .info = snd_ak4531_info_double, \
  .get = snd_ak4531_get_double, .put = snd_ak4531_put_double, \
  .private_value = left_reg | (right_reg << 8) | (left_shift << 16) | (right_shift << 19) | (mask << 24) | (invert << 22), \
  .tlv = { .p = (xtlv) } }

static int snd_ak4531_info_double(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
    int mask = (kcontrol->private_value >> 24) & 0xff;

    uinfo->type = mask == 1 ? SNDRV_CTL_ELEM_TYPE_BOOLEAN : SNDRV_CTL_ELEM_TYPE_INTEGER;
    uinfo->count = 2;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = mask;
    return 0;
}
 
static int snd_ak4531_get_double(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int left_reg = kcontrol->private_value & 0xff;
    int right_reg = (kcontrol->private_value >> 8) & 0xff;
    int left_shift = (kcontrol->private_value >> 16) & 0x07;
    int right_shift = (kcontrol->private_value >> 19) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;
    int left, right;

    mutex_lock(&ak4531->reg_mutex);
    left = (ak4531->regs[left_reg] >> left_shift) & mask;
    right = (ak4531->regs[right_reg] >> right_shift) & mask;
    mutex_unlock(&ak4531->reg_mutex);
    if (invert) {
        left = mask - left;
        right = mask - right;
    }
    ucontrol->value.integer.value[0] = left;
    ucontrol->value.integer.value[1] = right;
    return 0;
}

static int snd_ak4531_put_double(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int left_reg = kcontrol->private_value & 0xff;
    int right_reg = (kcontrol->private_value >> 8) & 0xff;
    int left_shift = (kcontrol->private_value >> 16) & 0x07;
    int right_shift = (kcontrol->private_value >> 19) & 0x07;
    int mask = (kcontrol->private_value >> 24) & 0xff;
    int invert = (kcontrol->private_value >> 22) & 1;
    int change;
    int left, right;

    left = ucontrol->value.integer.value[0] & mask;
    right = ucontrol->value.integer.value[1] & mask;
    if (invert) {
        left = mask - left;
        right = mask - right;
    }
    left <<= left_shift;
    right <<= right_shift;
    mutex_lock(&ak4531->reg_mutex);
    if (left_reg == right_reg) {
        left = (ak4531->regs[left_reg] & ~((mask << left_shift) | (mask << right_shift))) | left | right;
        change = left != ak4531->regs[left_reg];
        ak4531->write(ak4531, left_reg, ak4531->regs[left_reg] = left);
    } else {
        left = (ak4531->regs[left_reg] & ~(mask << left_shift)) | left;
        right = (ak4531->regs[right_reg] & ~(mask << right_shift)) | right;
        change = left != ak4531->regs[left_reg] || right != ak4531->regs[right_reg];
        ak4531->write(ak4531, left_reg, ak4531->regs[left_reg] = left);
        ak4531->write(ak4531, right_reg, ak4531->regs[right_reg] = right);
    }
    mutex_unlock(&ak4531->reg_mutex);
    return change;
}

#define AK4531_INPUT_SW(xname, xindex, reg1, reg2, left_shift, right_shift) \
{ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, .index = xindex, \
  .info = snd_ak4531_info_input_sw, \
  .get = snd_ak4531_get_input_sw, .put = snd_ak4531_put_input_sw, \
  .private_value = reg1 | (reg2 << 8) | (left_shift << 16) | (right_shift << 24) }

static int snd_ak4531_info_input_sw(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_info *uinfo)
{
    uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
    uinfo->count = 4;
    uinfo->value.integer.min = 0;
    uinfo->value.integer.max = 1;
    return 0;
}
 
static int snd_ak4531_get_input_sw(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int reg1 = kcontrol->private_value & 0xff;
    int reg2 = (kcontrol->private_value >> 8) & 0xff;
    int left_shift = (kcontrol->private_value >> 16) & 0x0f;
    int right_shift = (kcontrol->private_value >> 24) & 0x0f;

    mutex_lock(&ak4531->reg_mutex);
    ucontrol->value.integer.value[0] = (ak4531->regs[reg1] >> left_shift) & 1;
    ucontrol->value.integer.value[1] = (ak4531->regs[reg2] >> left_shift) & 1;
    ucontrol->value.integer.value[2] = (ak4531->regs[reg1] >> right_shift) & 1;
    ucontrol->value.integer.value[3] = (ak4531->regs[reg2] >> right_shift) & 1;
    mutex_unlock(&ak4531->reg_mutex);
    return 0;
}

static int snd_ak4531_put_input_sw(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
    struct snd_ak4531 *ak4531 = snd_kcontrol_chip(kcontrol);
    int reg1 = kcontrol->private_value & 0xff;
    int reg2 = (kcontrol->private_value >> 8) & 0xff;
    int left_shift = (kcontrol->private_value >> 16) & 0x0f;
    int right_shift = (kcontrol->private_value >> 24) & 0x0f;
    int change;
    int val1, val2;

    mutex_lock(&ak4531->reg_mutex);
    val1 = ak4531->regs[reg1] & ~((1 << left_shift) | (1 << right_shift));
    val2 = ak4531->regs[reg2] & ~((1 << left_shift) | (1 << right_shift));
    val1 |= (ucontrol->value.integer.value[0] & 1) << left_shift;
    val2 |= (ucontrol->value.integer.value[1] & 1) << left_shift;
    val1 |= (ucontrol->value.integer.value[2] & 1) << right_shift;
    val2 |= (ucontrol->value.integer.value[3] & 1) << right_shift;
    change = val1 != ak4531->regs[reg1] || val2 != ak4531->regs[reg2];
    ak4531->write(ak4531, reg1, ak4531->regs[reg1] = val1);
    ak4531->write(ak4531, reg2, ak4531->regs[reg2] = val2);
    mutex_unlock(&ak4531->reg_mutex);
    return change;
}

static const DECLARE_TLV_DB_SCALE(db_scale_master, -6200, 200, 0);
static const DECLARE_TLV_DB_SCALE(db_scale_mono, -2800, 400, 0);
static const DECLARE_TLV_DB_SCALE(db_scale_input, -5000, 200, 0);

static struct snd_kcontrol_new snd_ak4531_controls[] __devinitdata = {

AK4531_DOUBLE_TLV("Master Playback Switch", 0,
          AK4531_LMASTER, AK4531_RMASTER, 7, 7, 1, 1,
          db_scale_master),
AK4531_DOUBLE("Master Playback Volume", 0, AK4531_LMASTER, AK4531_RMASTER, 0, 0, 0x1f, 1),

AK4531_SINGLE_TLV("Master Mono Playback Switch", 0, AK4531_MONO_OUT, 7, 1, 1,
          db_scale_mono),
AK4531_SINGLE("Master Mono Playback Volume", 0, AK4531_MONO_OUT, 0, 0x07, 1),

AK4531_DOUBLE("PCM Switch", 0, AK4531_LVOICE, AK4531_RVOICE, 7, 7, 1, 1),
AK4531_DOUBLE_TLV("PCM Volume", 0, AK4531_LVOICE, AK4531_RVOICE, 0, 0, 0x1f, 1,
          db_scale_input),
AK4531_DOUBLE("PCM Playback Switch", 0, AK4531_OUT_SW2, AK4531_OUT_SW2, 3, 2, 1, 0),
AK4531_DOUBLE("PCM Capture Switch", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 2, 2, 1, 0),

AK4531_DOUBLE("PCM Switch", 1, AK4531_LFM, AK4531_RFM, 7, 7, 1, 1),
AK4531_DOUBLE_TLV("PCM Volume", 1, AK4531_LFM, AK4531_RFM, 0, 0, 0x1f, 1,
          db_scale_input),
AK4531_DOUBLE("PCM Playback Switch", 1, AK4531_OUT_SW1, AK4531_OUT_SW1, 6, 5, 1, 0),
AK4531_INPUT_SW("PCM Capture Route", 1, AK4531_LIN_SW1, AK4531_RIN_SW1, 6, 5),

AK4531_DOUBLE("CD Switch", 0, AK4531_LCD, AK4531_RCD, 7, 7, 1, 1),
AK4531_DOUBLE_TLV("CD Volume", 0, AK4531_LCD, AK4531_RCD, 0, 0, 0x1f, 1,
          db_scale_input),
AK4531_DOUBLE("CD Playback Switch", 0, AK4531_OUT_SW1, AK4531_OUT_SW1, 2, 1, 1, 0),
AK4531_INPUT_SW("CD Capture Route", 0, AK4531_LIN_SW1, AK4531_RIN_SW1, 2, 1),

AK4531_DOUBLE("Line Switch", 0, AK4531_LLINE, AK4531_RLINE, 7, 7, 1, 1),
AK4531_DOUBLE_TLV("Line Volume", 0, AK4531_LLINE, AK4531_RLINE, 0, 0, 0x1f, 1,
          db_scale_input),
AK4531_DOUBLE("Line Playback Switch", 0, AK4531_OUT_SW1, AK4531_OUT_SW1, 4, 3, 1, 0),
AK4531_INPUT_SW("Line Capture Route", 0, AK4531_LIN_SW1, AK4531_RIN_SW1, 4, 3),

AK4531_DOUBLE("Aux Switch", 0, AK4531_LAUXA, AK4531_RAUXA, 7, 7, 1, 1),
AK4531_DOUBLE_TLV("Aux Volume", 0, AK4531_LAUXA, AK4531_RAUXA, 0, 0, 0x1f, 1,
          db_scale_input),
AK4531_DOUBLE("Aux Playback Switch", 0, AK4531_OUT_SW2, AK4531_OUT_SW2, 5, 4, 1, 0),
AK4531_INPUT_SW("Aux Capture Route", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 4, 3),

AK4531_SINGLE("Mono Switch", 0, AK4531_MONO1, 7, 1, 1),
AK4531_SINGLE_TLV("Mono Volume", 0, AK4531_MONO1, 0, 0x1f, 1, db_scale_input),
AK4531_SINGLE("Mono Playback Switch", 0, AK4531_OUT_SW2, 0, 1, 0),
AK4531_DOUBLE("Mono Capture Switch", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 0, 0, 1, 0),

AK4531_SINGLE("Mono Switch", 1, AK4531_MONO2, 7, 1, 1),
AK4531_SINGLE_TLV("Mono Volume", 1, AK4531_MONO2, 0, 0x1f, 1, db_scale_input),
AK4531_SINGLE("Mono Playback Switch", 1, AK4531_OUT_SW2, 1, 1, 0),
AK4531_DOUBLE("Mono Capture Switch", 1, AK4531_LIN_SW2, AK4531_RIN_SW2, 1, 1, 1, 0),

AK4531_SINGLE_TLV("Mic Volume", 0, AK4531_MIC, 0, 0x1f, 1, db_scale_input),
AK4531_SINGLE("Mic Switch", 0, AK4531_MIC, 7, 1, 1),
AK4531_SINGLE("Mic Playback Switch", 0, AK4531_OUT_SW1, 0, 1, 0),
AK4531_DOUBLE("Mic Capture Switch", 0, AK4531_LIN_SW1, AK4531_RIN_SW1, 0, 0, 1, 0),

AK4531_DOUBLE("Mic Bypass Capture Switch", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 7, 7, 1, 0),
AK4531_DOUBLE("Mono1 Bypass Capture Switch", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 6, 6, 1, 0),
AK4531_DOUBLE("Mono2 Bypass Capture Switch", 0, AK4531_LIN_SW2, AK4531_RIN_SW2, 5, 5, 1, 0),

AK4531_SINGLE("AD Input Select", 0, AK4531_AD_IN, 0, 1, 0),
AK4531_SINGLE("Mic Boost (+30dB)", 0, AK4531_MIC_GAIN, 0, 1, 0)
};

static int snd_ak4531_free(struct snd_ak4531 *ak4531)
{
    if (ak4531) {
        if (ak4531->private_free)
            ak4531->private_free(ak4531);
        kfree(ak4531);
    }
    return 0;
}

static int snd_ak4531_dev_free(struct snd_device *device)
{
    struct snd_ak4531 *ak4531 = device->device_data;
    return snd_ak4531_free(ak4531);
}

static u8 snd_ak4531_initial_map[0x19 + 1] = {
    0x9f,       /* 00: Master Volume Lch */
    0x9f,       /* 01: Master Volume Rch */
    0x9f,       /* 02: Voice Volume Lch */
    0x9f,       /* 03: Voice Volume Rch */
    0x9f,       /* 04: FM Volume Lch */
    0x9f,       /* 05: FM Volume Rch */
    0x9f,       /* 06: CD Audio Volume Lch */
    0x9f,       /* 07: CD Audio Volume Rch */
    0x9f,       /* 08: Line Volume Lch */
    0x9f,       /* 09: Line Volume Rch */
    0x9f,       /* 0a: Aux Volume Lch */
    0x9f,       /* 0b: Aux Volume Rch */
    0x9f,       /* 0c: Mono1 Volume */
    0x9f,       /* 0d: Mono2 Volume */
    0x9f,       /* 0e: Mic Volume */
    0x87,       /* 0f: Mono-out Volume */
    0x00,       /* 10: Output Mixer SW1 */
    0x00,       /* 11: Output Mixer SW2 */
    0x00,       /* 12: Lch Input Mixer SW1 */
    0x00,       /* 13: Rch Input Mixer SW1 */
    0x00,       /* 14: Lch Input Mixer SW2 */
    0x00,       /* 15: Rch Input Mixer SW2 */
    0x00,       /* 16: Reset & Power Down */
    0x00,       /* 17: Clock Select */
    0x00,       /* 18: AD Input Select */
    0x01        /* 19: Mic Amp Setup */
};

int __devinit snd_ak4531_mixer(struct snd_card *card,
                   struct snd_ak4531 *_ak4531,
                   struct snd_ak4531 **rak4531)
{
    unsigned int idx;
    int err;
    struct snd_ak4531 *ak4531;
    static struct snd_device_ops ops = {
        .dev_free = snd_ak4531_dev_free,
    };

    if (snd_BUG_ON(!card || !_ak4531))
        return -EINVAL;
    if (rak4531)
        *rak4531 = NULL;
    ak4531 = kzalloc(sizeof(*ak4531), GFP_KERNEL);
    if (ak4531 == NULL)
        return -ENOMEM;
    *ak4531 = *_ak4531;
    mutex_init(&ak4531->reg_mutex);
    if ((err = snd_component_add(card, "AK4531")) < 0) {
        snd_ak4531_free(ak4531);
        return err;
    }
    strcpy(card->mixername, "Asahi Kasei AK4531");
    ak4531->write(ak4531, AK4531_RESET, 0x03);  /* no RST, PD */
    udelay(100);
    ak4531->write(ak4531, AK4531_CLOCK, 0x00);  /* CODEC ADC and CODEC DAC use {LR,B}CLK2 and run off LRCLK2 PLL */
    for (idx = 0; idx <= 0x19; idx++) {
        if (idx == AK4531_RESET || idx == AK4531_CLOCK)
            continue;
        ak4531->write(ak4531, idx, ak4531->regs[idx] = snd_ak4531_initial_map[idx]);    /* recording source is mixer */
    }
    for (idx = 0; idx < ARRAY_SIZE(snd_ak4531_controls); idx++) {
        if ((err = snd_ctl_add(card, snd_ctl_new1(&snd_ak4531_controls[idx], ak4531))) < 0) {
            snd_ak4531_free(ak4531);
            return err;
        }
    }
    snd_ak4531_proc_init(card, ak4531);
    if ((err = snd_device_new(card, SNDRV_DEV_CODEC, ak4531, &ops)) < 0) {
        snd_ak4531_free(ak4531);
        return err;
    }

#if 0
    snd_ak4531_dump(ak4531);
#endif
    if (rak4531)
        *rak4531 = ak4531;
    return 0;
}

/*
 * power management
 */
#ifdef CONFIG_PM
void snd_ak4531_suspend(struct snd_ak4531 *ak4531)
{
    /* mute */
    ak4531->write(ak4531, AK4531_LMASTER, 0x9f);
    ak4531->write(ak4531, AK4531_RMASTER, 0x9f);
    /* powerdown */
    ak4531->write(ak4531, AK4531_RESET, 0x01);
}

void snd_ak4531_resume(struct snd_ak4531 *ak4531)
{
    int idx;

    /* initialize */
    ak4531->write(ak4531, AK4531_RESET, 0x03);
    udelay(100);
    ak4531->write(ak4531, AK4531_CLOCK, 0x00);
    /* restore mixer registers */
    for (idx = 0; idx <= 0x19; idx++) {
        if (idx == AK4531_RESET || idx == AK4531_CLOCK)
            continue;
        ak4531->write(ak4531, idx, ak4531->regs[idx]);
    }
}
#endif

#ifdef CONFIG_PROC_FS
/*
 * /proc interface
 */

static void snd_ak4531_proc_read(struct snd_info_entry *entry, 
                 struct snd_info_buffer *buffer)
{
    struct snd_ak4531 *ak4531 = entry->private_data;

    snd_iprintf(buffer, "Asahi Kasei AK4531\n\n");
    snd_iprintf(buffer, "Recording source   : %s\n"
            "MIC gain           : %s\n",
            ak4531->regs[AK4531_AD_IN] & 1 ? "external" : "mixer",
            ak4531->regs[AK4531_MIC_GAIN] & 1 ? "+30dB" : "+0dB");
}

static void __devinit
snd_ak4531_proc_init(struct snd_card *card, struct snd_ak4531 *ak4531)
{
    struct snd_info_entry *entry;

    if (! snd_card_proc_new(card, "ak4531", &entry))
        snd_info_set_text_ops(entry, ak4531, snd_ak4531_proc_read);
}
#endif