wm8940.c

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/*
 * wm8940.c  --  WM8940 ALSA Soc Audio driver
 *
 * Author: Jonathan Cameron <[email protected]>
 *
 * Based on wm8510.c
 *    Copyright  2006 Wolfson Microelectronics PLC.
 *    Author:  Liam Girdwood <[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.
 *
 * Not currently handled:
 * Notch filter control
 * AUXMode (inverting vs mixer)
 * No means to obtain current gain if alc enabled.
 * No use made of gpio
 * Fast VMID discharge for power down
 * Soft Start
 * DLR and ALR Swaps not enabled
 * Digital Sidetone not supported
 */
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/i2c.h>
#include <linux/spi/spi.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 "wm8940.h"

struct wm8940_priv {
    unsigned int sysclk;
    enum snd_soc_control_type control_type;
};

static int wm8940_volatile_register(struct snd_soc_codec *codec,
                    unsigned int reg)
{
    switch (reg) {
    case WM8940_SOFTRESET:
        return 1;
    default:
        return 0;
    }
}

static u16 wm8940_reg_defaults[] = {
    0x8940, /* Soft Reset */
    0x0000, /* Power 1 */
    0x0000, /* Power 2 */
    0x0000, /* Power 3 */
    0x0010, /* Interface Control */
    0x0000, /* Companding Control */
    0x0140, /* Clock Control */
    0x0000, /* Additional Controls */
    0x0000, /* GPIO Control */
    0x0002, /* Auto Increment Control */
    0x0000, /* DAC Control */
    0x00FF, /* DAC Volume */
    0,
    0,
    0x0100, /* ADC Control */
    0x00FF, /* ADC Volume */
    0x0000, /* Notch Filter 1 Control 1 */
    0x0000, /* Notch Filter 1 Control 2 */
    0x0000, /* Notch Filter 2 Control 1 */
    0x0000, /* Notch Filter 2 Control 2 */
    0x0000, /* Notch Filter 3 Control 1 */
    0x0000, /* Notch Filter 3 Control 2 */
    0x0000, /* Notch Filter 4 Control 1 */
    0x0000, /* Notch Filter 4 Control 2 */
    0x0032, /* DAC Limit Control 1 */
    0x0000, /* DAC Limit Control 2 */
    0,
    0,
    0,
    0,
    0,
    0,
    0x0038, /* ALC Control 1 */
    0x000B, /* ALC Control 2 */
    0x0032, /* ALC Control 3 */
    0x0000, /* Noise Gate */
    0x0041, /* PLLN */
    0x000C, /* PLLK1 */
    0x0093, /* PLLK2 */
    0x00E9, /* PLLK3 */
    0,
    0,
    0x0030, /* ALC Control 4 */
    0,
    0x0002, /* Input Control */
    0x0050, /* PGA Gain */
    0,
    0x0002, /* ADC Boost Control */
    0,
    0x0002, /* Output Control */
    0x0000, /* Speaker Mixer Control */
    0,
    0,
    0,
    0x0079, /* Speaker Volume */
    0,
    0x0000, /* Mono Mixer Control */
};

static const char *wm8940_companding[] = { "Off", "NC", "u-law", "A-law" };
static const struct soc_enum wm8940_adc_companding_enum
= SOC_ENUM_SINGLE(WM8940_COMPANDINGCTL, 1, 4, wm8940_companding);
static const struct soc_enum wm8940_dac_companding_enum
= SOC_ENUM_SINGLE(WM8940_COMPANDINGCTL, 3, 4, wm8940_companding);

static const char *wm8940_alc_mode_text[] = {"ALC", "Limiter"};
static const struct soc_enum wm8940_alc_mode_enum
= SOC_ENUM_SINGLE(WM8940_ALC3, 8, 2, wm8940_alc_mode_text);

static const char *wm8940_mic_bias_level_text[] = {"0.9", "0.65"};
static const struct soc_enum wm8940_mic_bias_level_enum
= SOC_ENUM_SINGLE(WM8940_INPUTCTL, 8, 2, wm8940_mic_bias_level_text);

static const char *wm8940_filter_mode_text[] = {"Audio", "Application"};
static const struct soc_enum wm8940_filter_mode_enum
= SOC_ENUM_SINGLE(WM8940_ADC, 7, 2, wm8940_filter_mode_text);

static DECLARE_TLV_DB_SCALE(wm8940_spk_vol_tlv, -5700, 100, 1);
static DECLARE_TLV_DB_SCALE(wm8940_att_tlv, -1000, 1000, 0);
static DECLARE_TLV_DB_SCALE(wm8940_pga_vol_tlv, -1200, 75, 0);
static DECLARE_TLV_DB_SCALE(wm8940_alc_min_tlv, -1200, 600, 0);
static DECLARE_TLV_DB_SCALE(wm8940_alc_max_tlv, 675, 600, 0);
static DECLARE_TLV_DB_SCALE(wm8940_alc_tar_tlv, -2250, 50, 0);
static DECLARE_TLV_DB_SCALE(wm8940_lim_boost_tlv, 0, 100, 0);
static DECLARE_TLV_DB_SCALE(wm8940_lim_thresh_tlv, -600, 100, 0);
static DECLARE_TLV_DB_SCALE(wm8940_adc_tlv, -12750, 50, 1);
static DECLARE_TLV_DB_SCALE(wm8940_capture_boost_vol_tlv, 0, 2000, 0);

static const struct snd_kcontrol_new wm8940_snd_controls[] = {
    SOC_SINGLE("Digital Loopback Switch", WM8940_COMPANDINGCTL,
           6, 1, 0),
    SOC_ENUM("DAC Companding", wm8940_dac_companding_enum),
    SOC_ENUM("ADC Companding", wm8940_adc_companding_enum),

    SOC_ENUM("ALC Mode", wm8940_alc_mode_enum),
    SOC_SINGLE("ALC Switch", WM8940_ALC1, 8, 1, 0),
    SOC_SINGLE_TLV("ALC Capture Max Gain", WM8940_ALC1,
               3, 7, 1, wm8940_alc_max_tlv),
    SOC_SINGLE_TLV("ALC Capture Min Gain", WM8940_ALC1,
               0, 7, 0, wm8940_alc_min_tlv),
    SOC_SINGLE_TLV("ALC Capture Target", WM8940_ALC2,
               0, 14, 0, wm8940_alc_tar_tlv),
    SOC_SINGLE("ALC Capture Hold", WM8940_ALC2, 4, 10, 0),
    SOC_SINGLE("ALC Capture Decay", WM8940_ALC3, 4, 10, 0),
    SOC_SINGLE("ALC Capture Attach", WM8940_ALC3, 0, 10, 0),
    SOC_SINGLE("ALC ZC Switch", WM8940_ALC4, 1, 1, 0),
    SOC_SINGLE("ALC Capture Noise Gate Switch", WM8940_NOISEGATE,
           3, 1, 0),
    SOC_SINGLE("ALC Capture Noise Gate Threshold", WM8940_NOISEGATE,
           0, 7, 0),

    SOC_SINGLE("DAC Playback Limiter Switch", WM8940_DACLIM1, 8, 1, 0),
    SOC_SINGLE("DAC Playback Limiter Attack", WM8940_DACLIM1, 0, 9, 0),
    SOC_SINGLE("DAC Playback Limiter Decay", WM8940_DACLIM1, 4, 11, 0),
    SOC_SINGLE_TLV("DAC Playback Limiter Threshold", WM8940_DACLIM2,
               4, 9, 1, wm8940_lim_thresh_tlv),
    SOC_SINGLE_TLV("DAC Playback Limiter Boost", WM8940_DACLIM2,
               0, 12, 0, wm8940_lim_boost_tlv),

    SOC_SINGLE("Capture PGA ZC Switch", WM8940_PGAGAIN, 7, 1, 0),
    SOC_SINGLE_TLV("Capture PGA Volume", WM8940_PGAGAIN,
               0, 63, 0, wm8940_pga_vol_tlv),
    SOC_SINGLE_TLV("Digital Playback Volume", WM8940_DACVOL,
               0, 255, 0, wm8940_adc_tlv),
    SOC_SINGLE_TLV("Digital Capture Volume", WM8940_ADCVOL,
               0, 255, 0, wm8940_adc_tlv),
    SOC_ENUM("Mic Bias Level", wm8940_mic_bias_level_enum),
    SOC_SINGLE_TLV("Capture Boost Volue", WM8940_ADCBOOST,
               8, 1, 0, wm8940_capture_boost_vol_tlv),
    SOC_SINGLE_TLV("Speaker Playback Volume", WM8940_SPKVOL,
               0, 63, 0, wm8940_spk_vol_tlv),
    SOC_SINGLE("Speaker Playback Switch", WM8940_SPKVOL,  6, 1, 1),

    SOC_SINGLE_TLV("Speaker Mixer Line Bypass Volume", WM8940_SPKVOL,
               8, 1, 1, wm8940_att_tlv),
    SOC_SINGLE("Speaker Playback ZC Switch", WM8940_SPKVOL, 7, 1, 0),

    SOC_SINGLE("Mono Out Switch", WM8940_MONOMIX, 6, 1, 1),
    SOC_SINGLE_TLV("Mono Mixer Line Bypass Volume", WM8940_MONOMIX,
               7, 1, 1, wm8940_att_tlv),

    SOC_SINGLE("High Pass Filter Switch", WM8940_ADC, 8, 1, 0),
    SOC_ENUM("High Pass Filter Mode", wm8940_filter_mode_enum),
    SOC_SINGLE("High Pass Filter Cut Off", WM8940_ADC, 4, 7, 0),
    SOC_SINGLE("ADC Inversion Switch", WM8940_ADC, 0, 1, 0),
    SOC_SINGLE("DAC Inversion Switch", WM8940_DAC, 0, 1, 0),
    SOC_SINGLE("DAC Auto Mute Switch", WM8940_DAC, 2, 1, 0),
    SOC_SINGLE("ZC Timeout Clock Switch", WM8940_ADDCNTRL, 0, 1, 0),
};

static const struct snd_kcontrol_new wm8940_speaker_mixer_controls[] = {
    SOC_DAPM_SINGLE("Line Bypass Switch", WM8940_SPKMIX, 1, 1, 0),
    SOC_DAPM_SINGLE("Aux Playback Switch", WM8940_SPKMIX, 5, 1, 0),
    SOC_DAPM_SINGLE("PCM Playback Switch", WM8940_SPKMIX, 0, 1, 0),
};

static const struct snd_kcontrol_new wm8940_mono_mixer_controls[] = {
    SOC_DAPM_SINGLE("Line Bypass Switch", WM8940_MONOMIX, 1, 1, 0),
    SOC_DAPM_SINGLE("Aux Playback Switch", WM8940_MONOMIX, 2, 1, 0),
    SOC_DAPM_SINGLE("PCM Playback Switch", WM8940_MONOMIX, 0, 1, 0),
};

static DECLARE_TLV_DB_SCALE(wm8940_boost_vol_tlv, -1500, 300, 1);
static const struct snd_kcontrol_new wm8940_input_boost_controls[] = {
    SOC_DAPM_SINGLE("Mic PGA Switch", WM8940_PGAGAIN, 6, 1, 1),
    SOC_DAPM_SINGLE_TLV("Aux Volume", WM8940_ADCBOOST,
                0, 7, 0, wm8940_boost_vol_tlv),
    SOC_DAPM_SINGLE_TLV("Mic Volume", WM8940_ADCBOOST,
                4, 7, 0, wm8940_boost_vol_tlv),
};

static const struct snd_kcontrol_new wm8940_micpga_controls[] = {
    SOC_DAPM_SINGLE("AUX Switch", WM8940_INPUTCTL, 2, 1, 0),
    SOC_DAPM_SINGLE("MICP Switch", WM8940_INPUTCTL, 0, 1, 0),
    SOC_DAPM_SINGLE("MICN Switch", WM8940_INPUTCTL, 1, 1, 0),
};

static const struct snd_soc_dapm_widget wm8940_dapm_widgets[] = {
    SND_SOC_DAPM_MIXER("Speaker Mixer", WM8940_POWER3, 2, 0,
               &wm8940_speaker_mixer_controls[0],
               ARRAY_SIZE(wm8940_speaker_mixer_controls)),
    SND_SOC_DAPM_MIXER("Mono Mixer", WM8940_POWER3, 3, 0,
               &wm8940_mono_mixer_controls[0],
               ARRAY_SIZE(wm8940_mono_mixer_controls)),
    SND_SOC_DAPM_DAC("DAC", "HiFi Playback", WM8940_POWER3, 0, 0),

    SND_SOC_DAPM_PGA("SpkN Out", WM8940_POWER3, 5, 0, NULL, 0),
    SND_SOC_DAPM_PGA("SpkP Out", WM8940_POWER3, 6, 0, NULL, 0),
    SND_SOC_DAPM_PGA("Mono Out", WM8940_POWER3, 7, 0, NULL, 0),
    SND_SOC_DAPM_OUTPUT("MONOOUT"),
    SND_SOC_DAPM_OUTPUT("SPKOUTP"),
    SND_SOC_DAPM_OUTPUT("SPKOUTN"),

    SND_SOC_DAPM_PGA("Aux Input", WM8940_POWER1, 6, 0, NULL, 0),
    SND_SOC_DAPM_ADC("ADC", "HiFi Capture", WM8940_POWER2, 0, 0),
    SND_SOC_DAPM_MIXER("Mic PGA", WM8940_POWER2, 2, 0,
               &wm8940_micpga_controls[0],
               ARRAY_SIZE(wm8940_micpga_controls)),
    SND_SOC_DAPM_MIXER("Boost Mixer", WM8940_POWER2, 4, 0,
               &wm8940_input_boost_controls[0],
               ARRAY_SIZE(wm8940_input_boost_controls)),
    SND_SOC_DAPM_MICBIAS("Mic Bias", WM8940_POWER1, 4, 0),

    SND_SOC_DAPM_INPUT("MICN"),
    SND_SOC_DAPM_INPUT("MICP"),
    SND_SOC_DAPM_INPUT("AUX"),
};

static const struct snd_soc_dapm_route audio_map[] = {
    /* Mono output mixer */
    {"Mono Mixer", "PCM Playback Switch", "DAC"},
    {"Mono Mixer", "Aux Playback Switch", "Aux Input"},
    {"Mono Mixer", "Line Bypass Switch", "Boost Mixer"},

    /* Speaker output mixer */
    {"Speaker Mixer", "PCM Playback Switch", "DAC"},
    {"Speaker Mixer", "Aux Playback Switch", "Aux Input"},
    {"Speaker Mixer", "Line Bypass Switch", "Boost Mixer"},

    /* Outputs */
    {"Mono Out", NULL, "Mono Mixer"},
    {"MONOOUT", NULL, "Mono Out"},
    {"SpkN Out", NULL, "Speaker Mixer"},
    {"SpkP Out", NULL, "Speaker Mixer"},
    {"SPKOUTN", NULL, "SpkN Out"},
    {"SPKOUTP", NULL, "SpkP Out"},

    /*  Microphone PGA */
    {"Mic PGA", "MICN Switch", "MICN"},
    {"Mic PGA", "MICP Switch", "MICP"},
    {"Mic PGA", "AUX Switch", "AUX"},

    /* Boost Mixer */
    {"Boost Mixer", "Mic PGA Switch", "Mic PGA"},
    {"Boost Mixer", "Mic Volume",  "MICP"},
    {"Boost Mixer", "Aux Volume", "Aux Input"},

    {"ADC", NULL, "Boost Mixer"},
};

static int wm8940_add_widgets(struct snd_soc_codec *codec)
{
    struct snd_soc_dapm_context *dapm = &codec->dapm;
    int ret;

    ret = snd_soc_dapm_new_controls(dapm, wm8940_dapm_widgets,
                    ARRAY_SIZE(wm8940_dapm_widgets));
    if (ret)
        goto error_ret;
    ret = snd_soc_dapm_add_routes(dapm, audio_map, ARRAY_SIZE(audio_map));

error_ret:
    return ret;
}

#define wm8940_reset(c) snd_soc_write(c, WM8940_SOFTRESET, 0);

static int wm8940_set_dai_fmt(struct snd_soc_dai *codec_dai,
                  unsigned int fmt)
{
    struct snd_soc_codec *codec = codec_dai->codec;
    u16 iface = snd_soc_read(codec, WM8940_IFACE) & 0xFE67;
    u16 clk = snd_soc_read(codec, WM8940_CLOCK) & 0x1fe;

    switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
    case SND_SOC_DAIFMT_CBM_CFM:
        clk |= 1;
        break;
    case SND_SOC_DAIFMT_CBS_CFS:
        break;
    default:
        return -EINVAL;
    }
    snd_soc_write(codec, WM8940_CLOCK, clk);

    switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
    case SND_SOC_DAIFMT_I2S:
        iface |= (2 << 3);
        break;
    case SND_SOC_DAIFMT_LEFT_J:
        iface |= (1 << 3);
        break;
    case SND_SOC_DAIFMT_RIGHT_J:
        break;
    case SND_SOC_DAIFMT_DSP_A:
        iface |= (3 << 3);
        break;
    case SND_SOC_DAIFMT_DSP_B:
        iface |= (3 << 3) | (1 << 7);
        break;
    }

    switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
    case SND_SOC_DAIFMT_NB_NF:
        break;
    case SND_SOC_DAIFMT_NB_IF:
        iface |= (1 << 7);
        break;
    case SND_SOC_DAIFMT_IB_NF:
        iface |= (1 << 8);
        break;
    case SND_SOC_DAIFMT_IB_IF:
        iface |= (1 << 8) | (1 << 7);
        break;
    }

    snd_soc_write(codec, WM8940_IFACE, iface);

    return 0;
}

static int wm8940_i2s_hw_params(struct snd_pcm_substream *substream,
                struct snd_pcm_hw_params *params,
                struct snd_soc_dai *dai)
{
    struct snd_soc_codec *codec = dai->codec;
    u16 iface = snd_soc_read(codec, WM8940_IFACE) & 0xFD9F;
    u16 addcntrl = snd_soc_read(codec, WM8940_ADDCNTRL) & 0xFFF1;
    u16 companding =  snd_soc_read(codec,
                        WM8940_COMPANDINGCTL) & 0xFFDF;
    int ret;

    /* LoutR control */
    if (substream->stream == SNDRV_PCM_STREAM_CAPTURE
        && params_channels(params) == 2)
        iface |= (1 << 9);

    switch (params_rate(params)) {
    case 8000:
        addcntrl |= (0x5 << 1);
        break;
    case 11025:
        addcntrl |= (0x4 << 1);
        break;
    case 16000:
        addcntrl |= (0x3 << 1);
        break;
    case 22050:
        addcntrl |= (0x2 << 1);
        break;
    case 32000:
        addcntrl |= (0x1 << 1);
        break;
    case 44100:
    case 48000:
        break;
    }
    ret = snd_soc_write(codec, WM8940_ADDCNTRL, addcntrl);
    if (ret)
        goto error_ret;

    switch (params_format(params)) {
    case SNDRV_PCM_FORMAT_S8:
        companding = companding | (1 << 5);
        break;
    case SNDRV_PCM_FORMAT_S16_LE:
        break;
    case SNDRV_PCM_FORMAT_S20_3LE:
        iface |= (1 << 5);
        break;
    case SNDRV_PCM_FORMAT_S24_LE:
        iface |= (2 << 5);
        break;
    case SNDRV_PCM_FORMAT_S32_LE:
        iface |= (3 << 5);
        break;
    }
    ret = snd_soc_write(codec, WM8940_COMPANDINGCTL, companding);
    if (ret)
        goto error_ret;
    ret = snd_soc_write(codec, WM8940_IFACE, iface);

error_ret:
    return ret;
}

static int wm8940_mute(struct snd_soc_dai *dai, int mute)
{
    struct snd_soc_codec *codec = dai->codec;
    u16 mute_reg = snd_soc_read(codec, WM8940_DAC) & 0xffbf;

    if (mute)
        mute_reg |= 0x40;

    return snd_soc_write(codec, WM8940_DAC, mute_reg);
}

static int wm8940_set_bias_level(struct snd_soc_codec *codec,
                 enum snd_soc_bias_level level)
{
    u16 val;
    u16 pwr_reg = snd_soc_read(codec, WM8940_POWER1) & 0x1F0;
    int ret = 0;

    switch (level) {
    case SND_SOC_BIAS_ON:
        /* ensure bufioen and biasen */
        pwr_reg |= (1 << 2) | (1 << 3);
        /* Enable thermal shutdown */
        val = snd_soc_read(codec, WM8940_OUTPUTCTL);
        ret = snd_soc_write(codec, WM8940_OUTPUTCTL, val | 0x2);
        if (ret)
            break;
        /* set vmid to 75k */
        ret = snd_soc_write(codec, WM8940_POWER1, pwr_reg | 0x1);
        break;
    case SND_SOC_BIAS_PREPARE:
        /* ensure bufioen and biasen */
        pwr_reg |= (1 << 2) | (1 << 3);
        ret = snd_soc_write(codec, WM8940_POWER1, pwr_reg | 0x1);
        break;
    case SND_SOC_BIAS_STANDBY:
        if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
            ret = snd_soc_cache_sync(codec);
            if (ret < 0) {
                dev_err(codec->dev, "Failed to sync cache: %d\n", ret);
                return ret;
            }
        }

        /* ensure bufioen and biasen */
        pwr_reg |= (1 << 2) | (1 << 3);
        /* set vmid to 300k for standby */
        ret = snd_soc_write(codec, WM8940_POWER1, pwr_reg | 0x2);
        break;
    case SND_SOC_BIAS_OFF:
        ret = snd_soc_write(codec, WM8940_POWER1, pwr_reg);
        break;
    }

    codec->dapm.bias_level = level;

    return ret;
}

struct pll_ {
    unsigned int pre_scale:2;
    unsigned int n:4;
    unsigned int k;
};

static struct pll_ pll_div;

/* The size in bits of the pll divide multiplied by 10
 * to allow rounding later */
#define FIXED_PLL_SIZE ((1 << 24) * 10)
static void pll_factors(unsigned int target, unsigned int source)
{
    unsigned long long Kpart;
    unsigned int K, Ndiv, Nmod;
    /* The left shift ist to avoid accuracy loss when right shifting */
    Ndiv = target / source;

    if (Ndiv > 12) {
        source <<= 1;
        /* Multiply by 2 */
        pll_div.pre_scale = 0;
        Ndiv = target / source;
    } else if (Ndiv < 3) {
        source >>= 2;
        /* Divide by 4 */
        pll_div.pre_scale = 3;
        Ndiv = target / source;
    } else if (Ndiv < 6) {
        source >>= 1;
        /* divide by 2 */
        pll_div.pre_scale = 2;
        Ndiv = target / source;
    } else
        pll_div.pre_scale = 1;

    if ((Ndiv < 6) || (Ndiv > 12))
        printk(KERN_WARNING
            "WM8940 N value %d outwith recommended range!d\n",
            Ndiv);

    pll_div.n = Ndiv;
    Nmod = target % source;
    Kpart = FIXED_PLL_SIZE * (long long)Nmod;

    do_div(Kpart, source);

    K = Kpart & 0xFFFFFFFF;

    /* Check if we need to round */
    if ((K % 10) >= 5)
        K += 5;

    /* Move down to proper range now rounding is done */
    K /= 10;

    pll_div.k = K;
}

/* Untested at the moment */
static int wm8940_set_dai_pll(struct snd_soc_dai *codec_dai, int pll_id,
        int source, unsigned int freq_in, unsigned int freq_out)
{
    struct snd_soc_codec *codec = codec_dai->codec;
    u16 reg;

    /* Turn off PLL */
    reg = snd_soc_read(codec, WM8940_POWER1);
    snd_soc_write(codec, WM8940_POWER1, reg & 0x1df);

    if (freq_in == 0 || freq_out == 0) {
        /* Clock CODEC directly from MCLK */
        reg = snd_soc_read(codec, WM8940_CLOCK);
        snd_soc_write(codec, WM8940_CLOCK, reg & 0x0ff);
        /* Pll power down */
        snd_soc_write(codec, WM8940_PLLN, (1 << 7));
        return 0;
    }

    /* Pll is followed by a frequency divide by 4 */
    pll_factors(freq_out*4, freq_in);
    if (pll_div.k)
        snd_soc_write(codec, WM8940_PLLN,
                 (pll_div.pre_scale << 4) | pll_div.n | (1 << 6));
    else /* No factional component */
        snd_soc_write(codec, WM8940_PLLN,
                 (pll_div.pre_scale << 4) | pll_div.n);
    snd_soc_write(codec, WM8940_PLLK1, pll_div.k >> 18);
    snd_soc_write(codec, WM8940_PLLK2, (pll_div.k >> 9) & 0x1ff);
    snd_soc_write(codec, WM8940_PLLK3, pll_div.k & 0x1ff);
    /* Enable the PLL */
    reg = snd_soc_read(codec, WM8940_POWER1);
    snd_soc_write(codec, WM8940_POWER1, reg | 0x020);

    /* Run CODEC from PLL instead of MCLK */
    reg = snd_soc_read(codec, WM8940_CLOCK);
    snd_soc_write(codec, WM8940_CLOCK, reg | 0x100);

    return 0;
}

static int wm8940_set_dai_sysclk(struct snd_soc_dai *codec_dai,
                 int clk_id, unsigned int freq, int dir)
{
    struct snd_soc_codec *codec = codec_dai->codec;
    struct wm8940_priv *wm8940 = snd_soc_codec_get_drvdata(codec);

    switch (freq) {
    case 11289600:
    case 12000000:
    case 12288000:
    case 16934400:
    case 18432000:
        wm8940->sysclk = freq;
        return 0;
    }
    return -EINVAL;
}

static int wm8940_set_dai_clkdiv(struct snd_soc_dai *codec_dai,
                 int div_id, int div)
{
    struct snd_soc_codec *codec = codec_dai->codec;
    u16 reg;
    int ret = 0;

    switch (div_id) {
    case WM8940_BCLKDIV:
        reg = snd_soc_read(codec, WM8940_CLOCK) & 0xFFE3;
        ret = snd_soc_write(codec, WM8940_CLOCK, reg | (div << 2));
        break;
    case WM8940_MCLKDIV:
        reg = snd_soc_read(codec, WM8940_CLOCK) & 0xFF1F;
        ret = snd_soc_write(codec, WM8940_CLOCK, reg | (div << 5));
        break;
    case WM8940_OPCLKDIV:
        reg = snd_soc_read(codec, WM8940_GPIO) & 0xFFCF;
        ret = snd_soc_write(codec, WM8940_GPIO, reg | (div << 4));
        break;
    }
    return ret;
}

#define WM8940_RATES SNDRV_PCM_RATE_8000_48000

#define WM8940_FORMATS (SNDRV_PCM_FMTBIT_S8 |               \
            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 wm8940_dai_ops = {
    .hw_params = wm8940_i2s_hw_params,
    .set_sysclk = wm8940_set_dai_sysclk,
    .digital_mute = wm8940_mute,
    .set_fmt = wm8940_set_dai_fmt,
    .set_clkdiv = wm8940_set_dai_clkdiv,
    .set_pll = wm8940_set_dai_pll,
};

static struct snd_soc_dai_driver wm8940_dai = {
    .name = "wm8940-hifi",
    .playback = {
        .stream_name = "Playback",
        .channels_min = 1,
        .channels_max = 2,
        .rates = WM8940_RATES,
        .formats = WM8940_FORMATS,
    },
    .capture = {
        .stream_name = "Capture",
        .channels_min = 1,
        .channels_max = 2,
        .rates = WM8940_RATES,
        .formats = WM8940_FORMATS,
    },
    .ops = &wm8940_dai_ops,
    .symmetric_rates = 1,
};

static int wm8940_suspend(struct snd_soc_codec *codec)
{
    return wm8940_set_bias_level(codec, SND_SOC_BIAS_OFF);
}

static int wm8940_resume(struct snd_soc_codec *codec)
{
    wm8940_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
    return 0;
}

static int wm8940_probe(struct snd_soc_codec *codec)
{
    struct wm8940_priv *wm8940 = snd_soc_codec_get_drvdata(codec);
    struct wm8940_setup_data *pdata = codec->dev->platform_data;
    int ret;
    u16 reg;

    ret = snd_soc_codec_set_cache_io(codec, 8, 16, wm8940->control_type);
    if (ret < 0) {
        dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
        return ret;
    }

    ret = wm8940_reset(codec);
    if (ret < 0) {
        dev_err(codec->dev, "Failed to issue reset\n");
        return ret;
    }

    wm8940_set_bias_level(codec, SND_SOC_BIAS_STANDBY);

    ret = snd_soc_write(codec, WM8940_POWER1, 0x180);
    if (ret < 0)
        return ret;

    if (!pdata)
        dev_warn(codec->dev, "No platform data supplied\n");
    else {
        reg = snd_soc_read(codec, WM8940_OUTPUTCTL);
        ret = snd_soc_write(codec, WM8940_OUTPUTCTL, reg | pdata->vroi);
        if (ret < 0)
            return ret;
    }

    ret = snd_soc_add_codec_controls(codec, wm8940_snd_controls,
                 ARRAY_SIZE(wm8940_snd_controls));
    if (ret)
        return ret;
    ret = wm8940_add_widgets(codec);
    return ret;
}

static int wm8940_remove(struct snd_soc_codec *codec)
{
    wm8940_set_bias_level(codec, SND_SOC_BIAS_OFF);
    return 0;
}

static struct snd_soc_codec_driver soc_codec_dev_wm8940 = {
    .probe =    wm8940_probe,
    .remove =   wm8940_remove,
    .suspend =  wm8940_suspend,
    .resume =   wm8940_resume,
    .set_bias_level = wm8940_set_bias_level,
    .reg_cache_size = ARRAY_SIZE(wm8940_reg_defaults),
    .reg_word_size = sizeof(u16),
    .reg_cache_default = wm8940_reg_defaults,
    .volatile_register = wm8940_volatile_register,
};

static __devinit int wm8940_i2c_probe(struct i2c_client *i2c,
                      const struct i2c_device_id *id)
{
    struct wm8940_priv *wm8940;
    int ret;

    wm8940 = devm_kzalloc(&i2c->dev, sizeof(struct wm8940_priv),
                  GFP_KERNEL);
    if (wm8940 == NULL)
        return -ENOMEM;

    i2c_set_clientdata(i2c, wm8940);
    wm8940->control_type = SND_SOC_I2C;

    ret = snd_soc_register_codec(&i2c->dev,
            &soc_codec_dev_wm8940, &wm8940_dai, 1);

    return ret;
}

static __devexit int wm8940_i2c_remove(struct i2c_client *client)
{
    snd_soc_unregister_codec(&client->dev);

    return 0;
}

static const struct i2c_device_id wm8940_i2c_id[] = {
    { "wm8940", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, wm8940_i2c_id);

static struct i2c_driver wm8940_i2c_driver = {
    .driver = {
        .name = "wm8940",
        .owner = THIS_MODULE,
    },
    .probe =    wm8940_i2c_probe,
    .remove =   __devexit_p(wm8940_i2c_remove),
    .id_table = wm8940_i2c_id,
};

module_i2c_driver(wm8940_i2c_driver);

MODULE_DESCRIPTION("ASoC WM8940 driver");
MODULE_AUTHOR("Jonathan Cameron");
MODULE_LICENSE("GPL");