wm8770.c

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/*
 * wm8770.c  --  WM8770 ALSA SoC Audio driver
 *
 * Copyright 2010 Wolfson Microelectronics plc
 *
 * Author: Dimitris Papastamos <[email protected]>
 *
 * 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/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/of_device.h>
#include <linux/pm.h>
#include <linux/spi/spi.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/initval.h>
#include <sound/tlv.h>

#include "wm8770.h"

#define WM8770_NUM_SUPPLIES 3
static const char *wm8770_supply_names[WM8770_NUM_SUPPLIES] = {
    "AVDD1",
    "AVDD2",
    "DVDD"
};

static const u16 wm8770_reg_defs[WM8770_CACHEREGNUM] = {
    0x7f, 0x7f, 0x7f, 0x7f,
    0x7f, 0x7f, 0x7f, 0x7f,
    0x7f, 0xff, 0xff, 0xff,
    0xff, 0xff, 0xff, 0xff,
    0xff, 0xff, 0, 0x90, 0,
    0, 0x22, 0x22, 0x3e,
    0xc, 0xc, 0x100, 0x189,
    0x189, 0x8770
};

struct wm8770_priv {
    enum snd_soc_control_type control_type;
    struct regulator_bulk_data supplies[WM8770_NUM_SUPPLIES];
    struct notifier_block disable_nb[WM8770_NUM_SUPPLIES];
    struct snd_soc_codec *codec;
    int sysclk;
};

static int vout12supply_event(struct snd_soc_dapm_widget *w,
    struct snd_kcontrol *kcontrol, int event);
static int vout34supply_event(struct snd_soc_dapm_widget *w,
    struct snd_kcontrol *kcontrol, int event);

/*
 * We can't use the same notifier block for more than one supply and
 * there's no way I can see to get from a callback to the caller
 * except container_of().
 */
#define WM8770_REGULATOR_EVENT(n) \
static int wm8770_regulator_event_##n(struct notifier_block *nb, \
                      unsigned long event, void *data)    \
{ \
    struct wm8770_priv *wm8770 = container_of(nb, struct wm8770_priv, \
                     disable_nb[n]); \
    if (event & REGULATOR_EVENT_DISABLE) { \
        wm8770->codec->cache_sync = 1; \
    } \
    return 0; \
}

WM8770_REGULATOR_EVENT(0)
WM8770_REGULATOR_EVENT(1)
WM8770_REGULATOR_EVENT(2)

static const DECLARE_TLV_DB_SCALE(adc_tlv, -1200, 100, 0);
static const DECLARE_TLV_DB_SCALE(dac_dig_tlv, -12750, 50, 1);
static const DECLARE_TLV_DB_SCALE(dac_alg_tlv, -12700, 100, 1);

static const char *dac_phase_text[][2] = {
    { "DAC1 Normal", "DAC1 Inverted" },
    { "DAC2 Normal", "DAC2 Inverted" },
    { "DAC3 Normal", "DAC3 Inverted" },
    { "DAC4 Normal", "DAC4 Inverted" },
};

static const struct soc_enum dac_phase[] = {
    SOC_ENUM_DOUBLE(WM8770_DACPHASE, 0, 1, 2, dac_phase_text[0]),
    SOC_ENUM_DOUBLE(WM8770_DACPHASE, 2, 3, 2, dac_phase_text[1]),
    SOC_ENUM_DOUBLE(WM8770_DACPHASE, 4, 5, 2, dac_phase_text[2]),
    SOC_ENUM_DOUBLE(WM8770_DACPHASE, 6, 7, 2, dac_phase_text[3]),
};

static const struct snd_kcontrol_new wm8770_snd_controls[] = {
    /* global DAC playback controls */
    SOC_SINGLE_TLV("DAC Playback Volume", WM8770_MSDIGVOL, 0, 255, 0,
        dac_dig_tlv),
    SOC_SINGLE("DAC Playback Switch", WM8770_DACMUTE, 4, 1, 1),
    SOC_SINGLE("DAC Playback ZC Switch", WM8770_DACCTRL1, 0, 1, 0),

    /* global VOUT playback controls */
    SOC_SINGLE_TLV("VOUT Playback Volume", WM8770_MSALGVOL, 0, 127, 0,
        dac_alg_tlv),
    SOC_SINGLE("VOUT Playback ZC Switch", WM8770_MSALGVOL, 7, 1, 0),

    /* VOUT1/2/3/4 specific controls */
    SOC_DOUBLE_R_TLV("VOUT1 Playback Volume", WM8770_VOUT1LVOL,
        WM8770_VOUT1RVOL, 0, 127, 0, dac_alg_tlv),
    SOC_DOUBLE_R("VOUT1 Playback ZC Switch", WM8770_VOUT1LVOL,
        WM8770_VOUT1RVOL, 7, 1, 0),
    SOC_DOUBLE_R_TLV("VOUT2 Playback Volume", WM8770_VOUT2LVOL,
        WM8770_VOUT2RVOL, 0, 127, 0, dac_alg_tlv),
    SOC_DOUBLE_R("VOUT2 Playback ZC Switch", WM8770_VOUT2LVOL,
        WM8770_VOUT2RVOL, 7, 1, 0),
    SOC_DOUBLE_R_TLV("VOUT3 Playback Volume", WM8770_VOUT3LVOL,
        WM8770_VOUT3RVOL, 0, 127, 0, dac_alg_tlv),
    SOC_DOUBLE_R("VOUT3 Playback ZC Switch", WM8770_VOUT3LVOL,
        WM8770_VOUT3RVOL, 7, 1, 0),
    SOC_DOUBLE_R_TLV("VOUT4 Playback Volume", WM8770_VOUT4LVOL,
        WM8770_VOUT4RVOL, 0, 127, 0, dac_alg_tlv),
    SOC_DOUBLE_R("VOUT4 Playback ZC Switch", WM8770_VOUT4LVOL,
        WM8770_VOUT4RVOL, 7, 1, 0),

    /* DAC1/2/3/4 specific controls */
    SOC_DOUBLE_R_TLV("DAC1 Playback Volume", WM8770_DAC1LVOL,
        WM8770_DAC1RVOL, 0, 255, 0, dac_dig_tlv),
    SOC_SINGLE("DAC1 Deemphasis Switch", WM8770_DACCTRL2, 0, 1, 0),
    SOC_ENUM("DAC1 Phase", dac_phase[0]),
    SOC_DOUBLE_R_TLV("DAC2 Playback Volume", WM8770_DAC2LVOL,
        WM8770_DAC2RVOL, 0, 255, 0, dac_dig_tlv),
    SOC_SINGLE("DAC2 Deemphasis Switch", WM8770_DACCTRL2, 1, 1, 0),
    SOC_ENUM("DAC2 Phase", dac_phase[1]),
    SOC_DOUBLE_R_TLV("DAC3 Playback Volume", WM8770_DAC3LVOL,
        WM8770_DAC3RVOL, 0, 255, 0, dac_dig_tlv),
    SOC_SINGLE("DAC3 Deemphasis Switch", WM8770_DACCTRL2, 2, 1, 0),
    SOC_ENUM("DAC3 Phase", dac_phase[2]),
    SOC_DOUBLE_R_TLV("DAC4 Playback Volume", WM8770_DAC4LVOL,
        WM8770_DAC4RVOL, 0, 255, 0, dac_dig_tlv),
    SOC_SINGLE("DAC4 Deemphasis Switch", WM8770_DACCTRL2, 3, 1, 0),
    SOC_ENUM("DAC4 Phase", dac_phase[3]),

    /* ADC specific controls */
    SOC_DOUBLE_R_TLV("Capture Volume", WM8770_ADCLCTRL, WM8770_ADCRCTRL,
        0, 31, 0, adc_tlv),
    SOC_DOUBLE_R("Capture Switch", WM8770_ADCLCTRL, WM8770_ADCRCTRL,
        5, 1, 1),

    /* other controls */
    SOC_SINGLE("ADC 128x Oversampling Switch", WM8770_MSTRCTRL, 3, 1, 0),
    SOC_SINGLE("ADC Highpass Filter Switch", WM8770_IFACECTRL, 8, 1, 1)
};

static const char *ain_text[] = {
    "AIN1", "AIN2", "AIN3", "AIN4",
    "AIN5", "AIN6", "AIN7", "AIN8"
};

static const struct soc_enum ain_enum =
    SOC_ENUM_DOUBLE(WM8770_ADCMUX, 0, 4, 8, ain_text);

static const struct snd_kcontrol_new ain_mux =
    SOC_DAPM_ENUM("Capture Mux", ain_enum);

static const struct snd_kcontrol_new vout1_mix_controls[] = {
    SOC_DAPM_SINGLE("DAC1 Switch", WM8770_OUTMUX1, 0, 1, 0),
    SOC_DAPM_SINGLE("AUX1 Switch", WM8770_OUTMUX1, 1, 1, 0),
    SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX1, 2, 1, 0)
};

static const struct snd_kcontrol_new vout2_mix_controls[] = {
    SOC_DAPM_SINGLE("DAC2 Switch", WM8770_OUTMUX1, 3, 1, 0),
    SOC_DAPM_SINGLE("AUX2 Switch", WM8770_OUTMUX1, 4, 1, 0),
    SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX1, 5, 1, 0)
};

static const struct snd_kcontrol_new vout3_mix_controls[] = {
    SOC_DAPM_SINGLE("DAC3 Switch", WM8770_OUTMUX2, 0, 1, 0),
    SOC_DAPM_SINGLE("AUX3 Switch", WM8770_OUTMUX2, 1, 1, 0),
    SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX2, 2, 1, 0)
};

static const struct snd_kcontrol_new vout4_mix_controls[] = {
    SOC_DAPM_SINGLE("DAC4 Switch", WM8770_OUTMUX2, 3, 1, 0),
    SOC_DAPM_SINGLE("Bypass Switch", WM8770_OUTMUX2, 4, 1, 0)
};

static const struct snd_soc_dapm_widget wm8770_dapm_widgets[] = {
    SND_SOC_DAPM_INPUT("AUX1"),
    SND_SOC_DAPM_INPUT("AUX2"),
    SND_SOC_DAPM_INPUT("AUX3"),

    SND_SOC_DAPM_INPUT("AIN1"),
    SND_SOC_DAPM_INPUT("AIN2"),
    SND_SOC_DAPM_INPUT("AIN3"),
    SND_SOC_DAPM_INPUT("AIN4"),
    SND_SOC_DAPM_INPUT("AIN5"),
    SND_SOC_DAPM_INPUT("AIN6"),
    SND_SOC_DAPM_INPUT("AIN7"),
    SND_SOC_DAPM_INPUT("AIN8"),

    SND_SOC_DAPM_MUX("Capture Mux", WM8770_ADCMUX, 8, 1, &ain_mux),

    SND_SOC_DAPM_ADC("ADC", "Capture", WM8770_PWDNCTRL, 1, 1),

    SND_SOC_DAPM_DAC("DAC1", "Playback", WM8770_PWDNCTRL, 2, 1),
    SND_SOC_DAPM_DAC("DAC2", "Playback", WM8770_PWDNCTRL, 3, 1),
    SND_SOC_DAPM_DAC("DAC3", "Playback", WM8770_PWDNCTRL, 4, 1),
    SND_SOC_DAPM_DAC("DAC4", "Playback", WM8770_PWDNCTRL, 5, 1),

    SND_SOC_DAPM_SUPPLY("VOUT12 Supply", SND_SOC_NOPM, 0, 0,
        vout12supply_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),
    SND_SOC_DAPM_SUPPLY("VOUT34 Supply", SND_SOC_NOPM, 0, 0,
        vout34supply_event, SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD),

    SND_SOC_DAPM_MIXER("VOUT1 Mixer", SND_SOC_NOPM, 0, 0,
        vout1_mix_controls, ARRAY_SIZE(vout1_mix_controls)),
    SND_SOC_DAPM_MIXER("VOUT2 Mixer", SND_SOC_NOPM, 0, 0,
        vout2_mix_controls, ARRAY_SIZE(vout2_mix_controls)),
    SND_SOC_DAPM_MIXER("VOUT3 Mixer", SND_SOC_NOPM, 0, 0,
        vout3_mix_controls, ARRAY_SIZE(vout3_mix_controls)),
    SND_SOC_DAPM_MIXER("VOUT4 Mixer", SND_SOC_NOPM, 0, 0,
        vout4_mix_controls, ARRAY_SIZE(vout4_mix_controls)),

    SND_SOC_DAPM_OUTPUT("VOUT1"),
    SND_SOC_DAPM_OUTPUT("VOUT2"),
    SND_SOC_DAPM_OUTPUT("VOUT3"),
    SND_SOC_DAPM_OUTPUT("VOUT4")
};

static const struct snd_soc_dapm_route wm8770_intercon[] = {
    { "Capture Mux", "AIN1", "AIN1" },
    { "Capture Mux", "AIN2", "AIN2" },
    { "Capture Mux", "AIN3", "AIN3" },
    { "Capture Mux", "AIN4", "AIN4" },
    { "Capture Mux", "AIN5", "AIN5" },
    { "Capture Mux", "AIN6", "AIN6" },
    { "Capture Mux", "AIN7", "AIN7" },
    { "Capture Mux", "AIN8", "AIN8" },

    { "ADC", NULL, "Capture Mux" },

    { "VOUT1 Mixer", NULL, "VOUT12 Supply" },
    { "VOUT1 Mixer", "DAC1 Switch", "DAC1" },
    { "VOUT1 Mixer", "AUX1 Switch", "AUX1" },
    { "VOUT1 Mixer", "Bypass Switch", "Capture Mux" },

    { "VOUT2 Mixer", NULL, "VOUT12 Supply" },
    { "VOUT2 Mixer", "DAC2 Switch", "DAC2" },
    { "VOUT2 Mixer", "AUX2 Switch", "AUX2" },
    { "VOUT2 Mixer", "Bypass Switch", "Capture Mux" },

    { "VOUT3 Mixer", NULL, "VOUT34 Supply" },
    { "VOUT3 Mixer", "DAC3 Switch", "DAC3" },
    { "VOUT3 Mixer", "AUX3 Switch", "AUX3" },
    { "VOUT3 Mixer", "Bypass Switch", "Capture Mux" },

    { "VOUT4 Mixer", NULL, "VOUT34 Supply" },
    { "VOUT4 Mixer", "DAC4 Switch", "DAC4" },
    { "VOUT4 Mixer", "Bypass Switch", "Capture Mux" },

    { "VOUT1", NULL, "VOUT1 Mixer" },
    { "VOUT2", NULL, "VOUT2 Mixer" },
    { "VOUT3", NULL, "VOUT3 Mixer" },
    { "VOUT4", NULL, "VOUT4 Mixer" }
};

static int vout12supply_event(struct snd_soc_dapm_widget *w,
    struct snd_kcontrol *kcontrol, int event)
{
    struct snd_soc_codec *codec;

    codec = w->codec;

    switch (event) {
    case SND_SOC_DAPM_PRE_PMU:
        snd_soc_update_bits(codec, WM8770_OUTMUX1, 0x180, 0);
        break;
    case SND_SOC_DAPM_POST_PMD:
        snd_soc_update_bits(codec, WM8770_OUTMUX1, 0x180, 0x180);
        break;
    }

    return 0;
}

static int vout34supply_event(struct snd_soc_dapm_widget *w,
    struct snd_kcontrol *kcontrol, int event)
{
    struct snd_soc_codec *codec;

    codec = w->codec;

    switch (event) {
    case SND_SOC_DAPM_PRE_PMU:
        snd_soc_update_bits(codec, WM8770_OUTMUX2, 0x180, 0);
        break;
    case SND_SOC_DAPM_POST_PMD:
        snd_soc_update_bits(codec, WM8770_OUTMUX2, 0x180, 0x180);
        break;
    }

    return 0;
}

static int wm8770_reset(struct snd_soc_codec *codec)
{
    return snd_soc_write(codec, WM8770_RESET, 0);
}

static int wm8770_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
{
    struct snd_soc_codec *codec;
    int iface, master;

    codec = dai->codec;

    switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
    case SND_SOC_DAIFMT_CBM_CFM:
        master = 0x100;
        break;
    case SND_SOC_DAIFMT_CBS_CFS:
        master = 0;
        break;
    default:
        return -EINVAL;
    }

    iface = 0;
    switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
    case SND_SOC_DAIFMT_I2S:
        iface |= 0x2;
        break;
    case SND_SOC_DAIFMT_RIGHT_J:
        break;
    case SND_SOC_DAIFMT_LEFT_J:
        iface |= 0x1;
        break;
    default:
        return -EINVAL;
    }

    switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
    case SND_SOC_DAIFMT_NB_NF:
        break;
    case SND_SOC_DAIFMT_IB_IF:
        iface |= 0xc;
        break;
    case SND_SOC_DAIFMT_IB_NF:
        iface |= 0x8;
        break;
    case SND_SOC_DAIFMT_NB_IF:
        iface |= 0x4;
        break;
    default:
        return -EINVAL;
    }

    snd_soc_update_bits(codec, WM8770_IFACECTRL, 0xf, iface);
    snd_soc_update_bits(codec, WM8770_MSTRCTRL, 0x100, master);

    return 0;
}

static const int mclk_ratios[] = {
    128,
    192,
    256,
    384,
    512,
    768
};

static int wm8770_hw_params(struct snd_pcm_substream *substream,
                struct snd_pcm_hw_params *params,
                struct snd_soc_dai *dai)
{
    struct snd_soc_codec *codec;
    struct wm8770_priv *wm8770;
    int i;
    int iface;
    int shift;
    int ratio;

    codec = dai->codec;
    wm8770 = snd_soc_codec_get_drvdata(codec);

    iface = 0;
    switch (params_format(params)) {
    case SNDRV_PCM_FORMAT_S16_LE:
        break;
    case SNDRV_PCM_FORMAT_S20_3LE:
        iface |= 0x10;
        break;
    case SNDRV_PCM_FORMAT_S24_LE:
        iface |= 0x20;
        break;
    case SNDRV_PCM_FORMAT_S32_LE:
        iface |= 0x30;
        break;
    }

    switch (substream->stream) {
    case SNDRV_PCM_STREAM_PLAYBACK:
        i = 0;
        shift = 4;
        break;
    case SNDRV_PCM_STREAM_CAPTURE:
        i = 2;
        shift = 0;
        break;
    default:
        return -EINVAL;
    }

    /* Only need to set MCLK/LRCLK ratio if we're master */
    if (snd_soc_read(codec, WM8770_MSTRCTRL) & 0x100) {
        for (; i < ARRAY_SIZE(mclk_ratios); ++i) {
            ratio = wm8770->sysclk / params_rate(params);
            if (ratio == mclk_ratios[i])
                break;
        }

        if (i == ARRAY_SIZE(mclk_ratios)) {
            dev_err(codec->dev,
                "Unable to configure MCLK ratio %d/%d\n",
                wm8770->sysclk, params_rate(params));
            return -EINVAL;
        }

        dev_dbg(codec->dev, "MCLK is %dfs\n", mclk_ratios[i]);

        snd_soc_update_bits(codec, WM8770_MSTRCTRL, 0x7 << shift,
                    i << shift);
    }

    snd_soc_update_bits(codec, WM8770_IFACECTRL, 0x30, iface);

    return 0;
}

static int wm8770_mute(struct snd_soc_dai *dai, int mute)
{
    struct snd_soc_codec *codec;

    codec = dai->codec;
    return snd_soc_update_bits(codec, WM8770_DACMUTE, 0x10,
                   !!mute << 4);
}

static int wm8770_set_sysclk(struct snd_soc_dai *dai,
                 int clk_id, unsigned int freq, int dir)
{
    struct snd_soc_codec *codec;
    struct wm8770_priv *wm8770;

    codec = dai->codec;
    wm8770 = snd_soc_codec_get_drvdata(codec);
    wm8770->sysclk = freq;
    return 0;
}

static void wm8770_sync_cache(struct snd_soc_codec *codec)
{
    int i;
    u16 *cache;

    if (!codec->cache_sync)
        return;

    codec->cache_only = 0;
    cache = codec->reg_cache;
    for (i = 0; i < codec->driver->reg_cache_size; i++) {
        if (i == WM8770_RESET || cache[i] == wm8770_reg_defs[i])
            continue;
        snd_soc_write(codec, i, cache[i]);
    }
    codec->cache_sync = 0;
}

static int wm8770_set_bias_level(struct snd_soc_codec *codec,
                 enum snd_soc_bias_level level)
{
    int ret;
    struct wm8770_priv *wm8770;

    wm8770 = snd_soc_codec_get_drvdata(codec);

    switch (level) {
    case SND_SOC_BIAS_ON:
        break;
    case SND_SOC_BIAS_PREPARE:
        break;
    case SND_SOC_BIAS_STANDBY:
        if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
            ret = regulator_bulk_enable(ARRAY_SIZE(wm8770->supplies),
                            wm8770->supplies);
            if (ret) {
                dev_err(codec->dev,
                    "Failed to enable supplies: %d\n",
                    ret);
                return ret;
            }
            wm8770_sync_cache(codec);
            /* global powerup */
            snd_soc_write(codec, WM8770_PWDNCTRL, 0);
        }
        break;
    case SND_SOC_BIAS_OFF:
        /* global powerdown */
        snd_soc_write(codec, WM8770_PWDNCTRL, 1);
        regulator_bulk_disable(ARRAY_SIZE(wm8770->supplies),
                       wm8770->supplies);
        break;
    }

    codec->dapm.bias_level = level;
    return 0;
}

#define WM8770_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
            SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)

static const struct snd_soc_dai_ops wm8770_dai_ops = {
    .digital_mute = wm8770_mute,
    .hw_params = wm8770_hw_params,
    .set_fmt = wm8770_set_fmt,
    .set_sysclk = wm8770_set_sysclk,
};

static struct snd_soc_dai_driver wm8770_dai = {
    .name = "wm8770-hifi",
    .playback = {
        .stream_name = "Playback",
        .channels_min = 2,
        .channels_max = 2,
        .rates = SNDRV_PCM_RATE_8000_192000,
        .formats = WM8770_FORMATS
    },
    .capture = {
        .stream_name = "Capture",
        .channels_min = 2,
        .channels_max = 2,
        .rates = SNDRV_PCM_RATE_8000_96000,
        .formats = WM8770_FORMATS
    },
    .ops = &wm8770_dai_ops,
    .symmetric_rates = 1
};

#ifdef CONFIG_PM
static int wm8770_suspend(struct snd_soc_codec *codec)
{
    wm8770_set_bias_level(codec, SND_SOC_BIAS_OFF);
    return 0;
}

static int wm8770_resume(struct snd_soc_codec *codec)
{
    wm8770_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
    return 0;
}
#else
#define wm8770_suspend NULL
#define wm8770_resume NULL
#endif

static int wm8770_probe(struct snd_soc_codec *codec)
{
    struct wm8770_priv *wm8770;
    int ret;
    int i;

    wm8770 = snd_soc_codec_get_drvdata(codec);
    wm8770->codec = codec;

    ret = snd_soc_codec_set_cache_io(codec, 7, 9, wm8770->control_type);
    if (ret < 0) {
        dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
        return ret;
    }

    for (i = 0; i < ARRAY_SIZE(wm8770->supplies); i++)
        wm8770->supplies[i].supply = wm8770_supply_names[i];

    ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(wm8770->supplies),
                 wm8770->supplies);
    if (ret) {
        dev_err(codec->dev, "Failed to request supplies: %d\n", ret);
        return ret;
    }

    wm8770->disable_nb[0].notifier_call = wm8770_regulator_event_0;
    wm8770->disable_nb[1].notifier_call = wm8770_regulator_event_1;
    wm8770->disable_nb[2].notifier_call = wm8770_regulator_event_2;

    /* This should really be moved into the regulator core */
    for (i = 0; i < ARRAY_SIZE(wm8770->supplies); i++) {
        ret = regulator_register_notifier(wm8770->supplies[i].consumer,
                          &wm8770->disable_nb[i]);
        if (ret) {
            dev_err(codec->dev,
                "Failed to register regulator notifier: %d\n",
                ret);
        }
    }

    ret = regulator_bulk_enable(ARRAY_SIZE(wm8770->supplies),
                    wm8770->supplies);
    if (ret) {
        dev_err(codec->dev, "Failed to enable supplies: %d\n", ret);
        goto err_reg_get;
    }

    ret = wm8770_reset(codec);
    if (ret < 0) {
        dev_err(codec->dev, "Failed to issue reset: %d\n", ret);
        goto err_reg_enable;
    }

    wm8770_set_bias_level(codec, SND_SOC_BIAS_STANDBY);

    /* latch the volume update bits */
    snd_soc_update_bits(codec, WM8770_MSDIGVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_MSALGVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_VOUT1RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_VOUT2RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_VOUT3RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_VOUT4RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_DAC1RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_DAC2RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_DAC3RVOL, 0x100, 0x100);
    snd_soc_update_bits(codec, WM8770_DAC4RVOL, 0x100, 0x100);

    /* mute all DACs */
    snd_soc_update_bits(codec, WM8770_DACMUTE, 0x10, 0x10);

    snd_soc_add_codec_controls(codec, wm8770_snd_controls,
                 ARRAY_SIZE(wm8770_snd_controls));
    snd_soc_dapm_new_controls(&codec->dapm, wm8770_dapm_widgets,
                  ARRAY_SIZE(wm8770_dapm_widgets));
    snd_soc_dapm_add_routes(&codec->dapm, wm8770_intercon,
                ARRAY_SIZE(wm8770_intercon));
    return 0;

err_reg_enable:
    regulator_bulk_disable(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
err_reg_get:
    regulator_bulk_free(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
    return ret;
}

static int wm8770_remove(struct snd_soc_codec *codec)
{
    struct wm8770_priv *wm8770;
    int i;

    wm8770 = snd_soc_codec_get_drvdata(codec);
    wm8770_set_bias_level(codec, SND_SOC_BIAS_OFF);

    for (i = 0; i < ARRAY_SIZE(wm8770->supplies); ++i)
        regulator_unregister_notifier(wm8770->supplies[i].consumer,
                          &wm8770->disable_nb[i]);
    regulator_bulk_free(ARRAY_SIZE(wm8770->supplies), wm8770->supplies);
    return 0;
}

static struct snd_soc_codec_driver soc_codec_dev_wm8770 = {
    .probe = wm8770_probe,
    .remove = wm8770_remove,
    .suspend = wm8770_suspend,
    .resume = wm8770_resume,
    .set_bias_level = wm8770_set_bias_level,
    .idle_bias_off = true,
    .reg_cache_size = ARRAY_SIZE(wm8770_reg_defs),
    .reg_word_size = sizeof (u16),
    .reg_cache_default = wm8770_reg_defs
};

static const struct of_device_id wm8770_of_match[] = {
    { .compatible = "wlf,wm8770", },
    { }
};
MODULE_DEVICE_TABLE(of, wm8770_of_match);

static int __devinit wm8770_spi_probe(struct spi_device *spi)
{
    struct wm8770_priv *wm8770;
    int ret;

    wm8770 = devm_kzalloc(&spi->dev, sizeof(struct wm8770_priv),
                  GFP_KERNEL);
    if (!wm8770)
        return -ENOMEM;

    wm8770->control_type = SND_SOC_SPI;
    spi_set_drvdata(spi, wm8770);

    ret = snd_soc_register_codec(&spi->dev,
                     &soc_codec_dev_wm8770, &wm8770_dai, 1);

    return ret;
}

static int __devexit wm8770_spi_remove(struct spi_device *spi)
{
    snd_soc_unregister_codec(&spi->dev);
    return 0;
}

static struct spi_driver wm8770_spi_driver = {
    .driver = {
        .name = "wm8770",
        .owner = THIS_MODULE,
        .of_match_table = wm8770_of_match,
    },
    .probe = wm8770_spi_probe,
    .remove = __devexit_p(wm8770_spi_remove)
};

module_spi_driver(wm8770_spi_driver);

MODULE_DESCRIPTION("ASoC WM8770 driver");
MODULE_AUTHOR("Dimitris Papastamos <[email protected]>");
MODULE_LICENSE("GPL");