wm2000.c

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/*
 * wm2000.c  --  WM2000 ALSA Soc Audio driver
 *
 * Copyright 2008-2011 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <[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.
 *
 * The download image for the WM2000 will be requested as
 * 'wm2000_anc.bin' by default (overridable via platform data) at
 * runtime and is expected to be in flat binary format.  This is
 * generated by Wolfson configuration tools and includes
 * system-specific callibration information.  If supplied as a
 * sequence of ASCII-encoded hexidecimal bytes this can be converted
 * into a flat binary with a command such as this on the command line:
 *
 * perl -e 'while (<>) { s/[\r\n]+// ; printf("%c", hex($_)); }'
 *                 < file  > wm2000_anc.bin
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/firmware.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/debugfs.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 <sound/wm2000.h>

#include "wm2000.h"

#define WM2000_NUM_SUPPLIES 3

static const char *wm2000_supplies[WM2000_NUM_SUPPLIES] = {
    "SPKVDD",
    "DBVDD",
    "DCVDD",
};

enum wm2000_anc_mode {
    ANC_ACTIVE = 0,
    ANC_BYPASS = 1,
    ANC_STANDBY = 2,
    ANC_OFF = 3,
};

struct wm2000_priv {
    struct i2c_client *i2c;
    struct regmap *regmap;

    struct regulator_bulk_data supplies[WM2000_NUM_SUPPLIES];

    enum wm2000_anc_mode anc_mode;

    unsigned int anc_active:1;
    unsigned int anc_eng_ena:1;
    unsigned int spk_ena:1;

    unsigned int mclk_div:1;
    unsigned int speech_clarity:1;

    int anc_download_size;
    char *anc_download;
};

static int wm2000_write(struct i2c_client *i2c, unsigned int reg,
            unsigned int value)
{
    struct wm2000_priv *wm2000 = i2c_get_clientdata(i2c);
    return regmap_write(wm2000->regmap, reg, value);
}

static unsigned int wm2000_read(struct i2c_client *i2c, unsigned int r)
{
    struct wm2000_priv *wm2000 = i2c_get_clientdata(i2c);
    unsigned int val;
    int ret;

    ret = regmap_read(wm2000->regmap, r, &val);
    if (ret < 0)
        return -1;

    return val;
}

static void wm2000_reset(struct wm2000_priv *wm2000)
{
    struct i2c_client *i2c = wm2000->i2c;

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_CLR);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);
    wm2000_write(i2c, WM2000_REG_ID1, 0);

    wm2000->anc_mode = ANC_OFF;
}

static int wm2000_poll_bit(struct i2c_client *i2c,
               unsigned int reg, u8 mask)
{
    int timeout = 4000;
    int val;

    val = wm2000_read(i2c, reg);

    while (!(val & mask) && --timeout) {
        msleep(1);
        val = wm2000_read(i2c, reg);
    }

    if (timeout == 0)
        return 0;
    else
        return 1;
}

static int wm2000_power_up(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);
    int ret;

    BUG_ON(wm2000->anc_mode != ANC_OFF);

    dev_dbg(&i2c->dev, "Beginning power up\n");

    ret = regulator_bulk_enable(WM2000_NUM_SUPPLIES, wm2000->supplies);
    if (ret != 0) {
        dev_err(&i2c->dev, "Failed to enable supplies: %d\n", ret);
        return ret;
    }

    if (!wm2000->mclk_div) {
        dev_dbg(&i2c->dev, "Disabling MCLK divider\n");
        wm2000_write(i2c, WM2000_REG_SYS_CTL2,
                 WM2000_MCLK_DIV2_ENA_CLR);
    } else {
        dev_dbg(&i2c->dev, "Enabling MCLK divider\n");
        wm2000_write(i2c, WM2000_REG_SYS_CTL2,
                 WM2000_MCLK_DIV2_ENA_SET);
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_CLR);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_ENG_SET);

    /* Wait for ANC engine to become ready */
    if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
                 WM2000_ANC_ENG_IDLE)) {
        dev_err(&i2c->dev, "ANC engine failed to reset\n");
        regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);
        return -ETIMEDOUT;
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_BOOT_COMPLETE)) {
        dev_err(&i2c->dev, "ANC engine failed to initialise\n");
        regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);
        return -ETIMEDOUT;
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);

    /* Open code download of the data since it is the only bulk
     * write we do. */
    dev_dbg(&i2c->dev, "Downloading %d bytes\n",
        wm2000->anc_download_size - 2);

    ret = i2c_master_send(i2c, wm2000->anc_download,
                  wm2000->anc_download_size);
    if (ret < 0) {
        dev_err(&i2c->dev, "i2c_transfer() failed: %d\n", ret);
        regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);
        return ret;
    }
    if (ret != wm2000->anc_download_size) {
        dev_err(&i2c->dev, "i2c_transfer() failed, %d != %d\n",
            ret, wm2000->anc_download_size);
        regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);
        return -EIO;
    }

    dev_dbg(&i2c->dev, "Download complete\n");

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_ANA_VMID_PU_TIME, 248 / 4);

        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_MOUSE_ENABLE |
                 WM2000_MODE_THERMAL_ENABLE);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_MOUSE_ENABLE |
                 WM2000_MODE_THERMAL_ENABLE);
    }

    ret = wm2000_read(i2c, WM2000_REG_SPEECH_CLARITY);
    if (wm2000->speech_clarity)
        ret &= ~WM2000_SPEECH_CLARITY;
    else
        ret |= WM2000_SPEECH_CLARITY;
    wm2000_write(i2c, WM2000_REG_SPEECH_CLARITY, ret);

    wm2000_write(i2c, WM2000_REG_SYS_START0, 0x33);
    wm2000_write(i2c, WM2000_REG_SYS_START1, 0x02);

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_MOUSE_ACTIVE)) {
        dev_err(&i2c->dev, "Timed out waiting for device\n");
        regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);
        return -ETIMEDOUT;
    }

    dev_dbg(&i2c->dev, "ANC active\n");
    if (analogue)
        dev_dbg(&i2c->dev, "Analogue active\n");
    wm2000->anc_mode = ANC_ACTIVE;

    return 0;
}

static int wm2000_power_down(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_ANA_VMID_PD_TIME, 248 / 4);
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_POWER_DOWN);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_POWER_DOWN);
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_POWER_DOWN_COMPLETE)) {
        dev_err(&i2c->dev, "Timeout waiting for ANC power down\n");
        return -ETIMEDOUT;
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
                 WM2000_ANC_ENG_IDLE)) {
        dev_err(&i2c->dev, "Timeout waiting for ANC engine idle\n");
        return -ETIMEDOUT;
    }

    regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);

    dev_dbg(&i2c->dev, "powered off\n");
    wm2000->anc_mode = ANC_OFF;

    return 0;
}

static int wm2000_enter_bypass(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);

    BUG_ON(wm2000->anc_mode != ANC_ACTIVE);

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_BYPASS_ENTRY);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_BYPASS_ENTRY);
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_ANC_DISABLED)) {
        dev_err(&i2c->dev, "Timeout waiting for ANC disable\n");
        return -ETIMEDOUT;
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT,
                 WM2000_ANC_ENG_IDLE)) {
        dev_err(&i2c->dev, "Timeout waiting for ANC engine idle\n");
        return -ETIMEDOUT;
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL1, WM2000_SYS_STBY);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);

    wm2000->anc_mode = ANC_BYPASS;
    dev_dbg(&i2c->dev, "bypass enabled\n");

    return 0;
}

static int wm2000_exit_bypass(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);

    BUG_ON(wm2000->anc_mode != ANC_BYPASS);
    
    wm2000_write(i2c, WM2000_REG_SYS_CTL1, 0);

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_MOUSE_ENABLE |
                 WM2000_MODE_THERMAL_ENABLE);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_MOUSE_ENABLE |
                 WM2000_MODE_THERMAL_ENABLE);
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_MOUSE_ACTIVE)) {
        dev_err(&i2c->dev, "Timed out waiting for MOUSE\n");
        return -ETIMEDOUT;
    }

    wm2000->anc_mode = ANC_ACTIVE;
    dev_dbg(&i2c->dev, "MOUSE active\n");

    return 0;
}

static int wm2000_enter_standby(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);

    BUG_ON(wm2000->anc_mode != ANC_ACTIVE);

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_ANA_VMID_PD_TIME, 248 / 4);

        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_STANDBY_ENTRY);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_STANDBY_ENTRY);
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_ANC_DISABLED)) {
        dev_err(&i2c->dev,
            "Timed out waiting for ANC disable after 1ms\n");
        return -ETIMEDOUT;
    }

    if (!wm2000_poll_bit(i2c, WM2000_REG_ANC_STAT, WM2000_ANC_ENG_IDLE)) {
        dev_err(&i2c->dev,
            "Timed out waiting for standby\n");
        return -ETIMEDOUT;
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL1, WM2000_SYS_STBY);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_CLR);

    wm2000->anc_mode = ANC_STANDBY;
    dev_dbg(&i2c->dev, "standby\n");
    if (analogue)
        dev_dbg(&i2c->dev, "Analogue disabled\n");

    return 0;
}

static int wm2000_exit_standby(struct i2c_client *i2c, int analogue)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(&i2c->dev);

    BUG_ON(wm2000->anc_mode != ANC_STANDBY);

    wm2000_write(i2c, WM2000_REG_SYS_CTL1, 0);

    if (analogue) {
        wm2000_write(i2c, WM2000_REG_ANA_VMID_PU_TIME, 248 / 4);

        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_ANA_SEQ_INCLUDE |
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_MOUSE_ENABLE);
    } else {
        wm2000_write(i2c, WM2000_REG_SYS_MODE_CNTRL,
                 WM2000_MODE_THERMAL_ENABLE |
                 WM2000_MODE_MOUSE_ENABLE);
    }

    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_RAM_SET);
    wm2000_write(i2c, WM2000_REG_SYS_CTL2, WM2000_ANC_INT_N_CLR);

    if (!wm2000_poll_bit(i2c, WM2000_REG_SYS_STATUS,
                 WM2000_STATUS_MOUSE_ACTIVE)) {
        dev_err(&i2c->dev, "Timed out waiting for MOUSE\n");
        return -ETIMEDOUT;
    }

    wm2000->anc_mode = ANC_ACTIVE;
    dev_dbg(&i2c->dev, "MOUSE active\n");
    if (analogue)
        dev_dbg(&i2c->dev, "Analogue enabled\n");

    return 0;
}

typedef int (*wm2000_mode_fn)(struct i2c_client *i2c, int analogue);

static struct {
    enum wm2000_anc_mode source;
    enum wm2000_anc_mode dest;
    int analogue;
    wm2000_mode_fn step[2];
} anc_transitions[] = {
    {
        .source = ANC_OFF,
        .dest = ANC_ACTIVE,
        .analogue = 1,
        .step = {
            wm2000_power_up,
        },
    },
    {
        .source = ANC_OFF,
        .dest = ANC_STANDBY,
        .step = {
            wm2000_power_up,
            wm2000_enter_standby,
        },
    },
    {
        .source = ANC_OFF,
        .dest = ANC_BYPASS,
        .analogue = 1,
        .step = {
            wm2000_power_up,
            wm2000_enter_bypass,
        },
    },
    {
        .source = ANC_ACTIVE,
        .dest = ANC_BYPASS,
        .analogue = 1,
        .step = {
            wm2000_enter_bypass,
        },
    },
    {
        .source = ANC_ACTIVE,
        .dest = ANC_STANDBY,
        .analogue = 1,
        .step = {
            wm2000_enter_standby,
        },
    },
    {
        .source = ANC_ACTIVE,
        .dest = ANC_OFF,
        .analogue = 1,
        .step = {
            wm2000_power_down,
        },
    },
    {
        .source = ANC_BYPASS,
        .dest = ANC_ACTIVE,
        .analogue = 1,
        .step = {
            wm2000_exit_bypass,
        },
    },
    {
        .source = ANC_BYPASS,
        .dest = ANC_STANDBY,
        .analogue = 1,
        .step = {
            wm2000_exit_bypass,
            wm2000_enter_standby,
        },
    },
    {
        .source = ANC_BYPASS,
        .dest = ANC_OFF,
        .step = {
            wm2000_exit_bypass,
            wm2000_power_down,
        },
    },
    {
        .source = ANC_STANDBY,
        .dest = ANC_ACTIVE,
        .analogue = 1,
        .step = {
            wm2000_exit_standby,
        },
    },
    {
        .source = ANC_STANDBY,
        .dest = ANC_BYPASS,
        .analogue = 1,
        .step = {
            wm2000_exit_standby,
            wm2000_enter_bypass,
        },
    },
    {
        .source = ANC_STANDBY,
        .dest = ANC_OFF,
        .step = {
            wm2000_exit_standby,
            wm2000_power_down,
        },
    },
};

static int wm2000_anc_transition(struct wm2000_priv *wm2000,
                 enum wm2000_anc_mode mode)
{
    struct i2c_client *i2c = wm2000->i2c;
    int i, j;
    int ret;

    if (wm2000->anc_mode == mode)
        return 0;

    for (i = 0; i < ARRAY_SIZE(anc_transitions); i++)
        if (anc_transitions[i].source == wm2000->anc_mode &&
            anc_transitions[i].dest == mode)
            break;
    if (i == ARRAY_SIZE(anc_transitions)) {
        dev_err(&i2c->dev, "No transition for %d->%d\n",
            wm2000->anc_mode, mode);
        return -EINVAL;
    }

    for (j = 0; j < ARRAY_SIZE(anc_transitions[j].step); j++) {
        if (!anc_transitions[i].step[j])
            break;
        ret = anc_transitions[i].step[j](i2c,
                         anc_transitions[i].analogue);
        if (ret != 0)
            return ret;
    }

    return 0;
}

static int wm2000_anc_set_mode(struct wm2000_priv *wm2000)
{
    struct i2c_client *i2c = wm2000->i2c;
    enum wm2000_anc_mode mode;

    if (wm2000->anc_eng_ena && wm2000->spk_ena)
        if (wm2000->anc_active)
            mode = ANC_ACTIVE;
        else
            mode = ANC_BYPASS;
    else
        mode = ANC_STANDBY;

    dev_dbg(&i2c->dev, "Set mode %d (enabled %d, mute %d, active %d)\n",
        mode, wm2000->anc_eng_ena, !wm2000->spk_ena,
        wm2000->anc_active);

    return wm2000_anc_transition(wm2000, mode);
}

static int wm2000_anc_mode_get(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    ucontrol->value.enumerated.item[0] = wm2000->anc_active;

    return 0;
}

static int wm2000_anc_mode_put(struct snd_kcontrol *kcontrol,
                   struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);
    int anc_active = ucontrol->value.enumerated.item[0];

    if (anc_active > 1)
        return -EINVAL;

    wm2000->anc_active = anc_active;

    return wm2000_anc_set_mode(wm2000);
}

static int wm2000_speaker_get(struct snd_kcontrol *kcontrol,
                  struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    ucontrol->value.enumerated.item[0] = wm2000->spk_ena;

    return 0;
}

static int wm2000_speaker_put(struct snd_kcontrol *kcontrol,
                  struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);
    int val = ucontrol->value.enumerated.item[0];

    if (val > 1)
        return -EINVAL;

    wm2000->spk_ena = val;

    return wm2000_anc_set_mode(wm2000);
}

static const struct snd_kcontrol_new wm2000_controls[] = {
    SOC_SINGLE_BOOL_EXT("WM2000 ANC Switch", 0,
                wm2000_anc_mode_get,
                wm2000_anc_mode_put),
    SOC_SINGLE_BOOL_EXT("WM2000 Switch", 0,
                wm2000_speaker_get,
                wm2000_speaker_put),
};

static int wm2000_anc_power_event(struct snd_soc_dapm_widget *w,
                  struct snd_kcontrol *kcontrol, int event)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    if (SND_SOC_DAPM_EVENT_ON(event))
        wm2000->anc_eng_ena = 1;

    if (SND_SOC_DAPM_EVENT_OFF(event))
        wm2000->anc_eng_ena = 0;

    return wm2000_anc_set_mode(wm2000);
}

static const struct snd_soc_dapm_widget wm2000_dapm_widgets[] = {
/* Externally visible pins */
SND_SOC_DAPM_OUTPUT("SPKN"),
SND_SOC_DAPM_OUTPUT("SPKP"),

SND_SOC_DAPM_INPUT("LINN"),
SND_SOC_DAPM_INPUT("LINP"),

SND_SOC_DAPM_PGA_E("ANC Engine", SND_SOC_NOPM, 0, 0, NULL, 0,
           wm2000_anc_power_event,
           SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
};

/* Target, Path, Source */
static const struct snd_soc_dapm_route wm2000_audio_map[] = {
    { "SPKN", NULL, "ANC Engine" },
    { "SPKP", NULL, "ANC Engine" },
    { "ANC Engine", NULL, "LINN" },
    { "ANC Engine", NULL, "LINP" },
};

#ifdef CONFIG_PM
static int wm2000_suspend(struct snd_soc_codec *codec)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    return wm2000_anc_transition(wm2000, ANC_OFF);
}

static int wm2000_resume(struct snd_soc_codec *codec)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    return wm2000_anc_set_mode(wm2000);
}
#else
#define wm2000_suspend NULL
#define wm2000_resume NULL
#endif

static bool wm2000_readable_reg(struct device *dev, unsigned int reg)
{
    switch (reg) {
    case WM2000_REG_SYS_START:
    case WM2000_REG_SPEECH_CLARITY:
    case WM2000_REG_SYS_WATCHDOG:
    case WM2000_REG_ANA_VMID_PD_TIME:
    case WM2000_REG_ANA_VMID_PU_TIME:
    case WM2000_REG_CAT_FLTR_INDX:
    case WM2000_REG_CAT_GAIN_0:
    case WM2000_REG_SYS_STATUS:
    case WM2000_REG_SYS_MODE_CNTRL:
    case WM2000_REG_SYS_START0:
    case WM2000_REG_SYS_START1:
    case WM2000_REG_ID1:
    case WM2000_REG_ID2:
    case WM2000_REG_REVISON:
    case WM2000_REG_SYS_CTL1:
    case WM2000_REG_SYS_CTL2:
    case WM2000_REG_ANC_STAT:
    case WM2000_REG_IF_CTL:
        return true;
    default:
        return false;
    }
}

static const struct regmap_config wm2000_regmap = {
    .reg_bits = 16,
    .val_bits = 8,

    .max_register = WM2000_REG_IF_CTL,
    .readable_reg = wm2000_readable_reg,
};

static int wm2000_probe(struct snd_soc_codec *codec)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    /* This will trigger a transition to standby mode by default */
    wm2000_anc_set_mode(wm2000);

    return 0;
}

static int wm2000_remove(struct snd_soc_codec *codec)
{
    struct wm2000_priv *wm2000 = dev_get_drvdata(codec->dev);

    return wm2000_anc_transition(wm2000, ANC_OFF);
}

static struct snd_soc_codec_driver soc_codec_dev_wm2000 = {
    .probe = wm2000_probe,
    .remove = wm2000_remove,
    .suspend = wm2000_suspend,
    .resume = wm2000_resume,

    .dapm_widgets = wm2000_dapm_widgets,
    .num_dapm_widgets = ARRAY_SIZE(wm2000_dapm_widgets),
    .dapm_routes = wm2000_audio_map,
    .num_dapm_routes = ARRAY_SIZE(wm2000_audio_map),
    .controls = wm2000_controls,
    .num_controls = ARRAY_SIZE(wm2000_controls),
};

static int __devinit wm2000_i2c_probe(struct i2c_client *i2c,
                      const struct i2c_device_id *i2c_id)
{
    struct wm2000_priv *wm2000;
    struct wm2000_platform_data *pdata;
    const char *filename;
    const struct firmware *fw = NULL;
    int ret, i;
    int reg;
    u16 id;

    wm2000 = devm_kzalloc(&i2c->dev, sizeof(struct wm2000_priv),
                  GFP_KERNEL);
    if (wm2000 == NULL) {
        dev_err(&i2c->dev, "Unable to allocate private data\n");
        return -ENOMEM;
    }

    dev_set_drvdata(&i2c->dev, wm2000);

    wm2000->regmap = devm_regmap_init_i2c(i2c, &wm2000_regmap);
    if (IS_ERR(wm2000->regmap)) {
        ret = PTR_ERR(wm2000->regmap);
        dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
            ret);
        goto out;
    }

    for (i = 0; i < WM2000_NUM_SUPPLIES; i++)
        wm2000->supplies[i].supply = wm2000_supplies[i];

    ret = devm_regulator_bulk_get(&i2c->dev, WM2000_NUM_SUPPLIES,
                      wm2000->supplies);
    if (ret != 0) {
        dev_err(&i2c->dev, "Failed to get supplies: %d\n", ret);
        return ret;
    }

    ret = regulator_bulk_enable(WM2000_NUM_SUPPLIES, wm2000->supplies);
    if (ret != 0) {
        dev_err(&i2c->dev, "Failed to enable supplies: %d\n", ret);
        return ret;
    }

    /* Verify that this is a WM2000 */
    reg = wm2000_read(i2c, WM2000_REG_ID1);
    id = reg << 8;
    reg = wm2000_read(i2c, WM2000_REG_ID2);
    id |= reg & 0xff;

    if (id != 0x2000) {
        dev_err(&i2c->dev, "Device is not a WM2000 - ID %x\n", id);
        ret = -ENODEV;
        goto err_supplies;
    }

    reg = wm2000_read(i2c, WM2000_REG_REVISON);
    dev_info(&i2c->dev, "revision %c\n", reg + 'A');

    filename = "wm2000_anc.bin";
    pdata = dev_get_platdata(&i2c->dev);
    if (pdata) {
        wm2000->mclk_div = pdata->mclkdiv2;
        wm2000->speech_clarity = !pdata->speech_enh_disable;

        if (pdata->download_file)
            filename = pdata->download_file;
    }

    ret = request_firmware(&fw, filename, &i2c->dev);
    if (ret != 0) {
        dev_err(&i2c->dev, "Failed to acquire ANC data: %d\n", ret);
        goto err_supplies;
    }

    /* Pre-cook the concatenation of the register address onto the image */
    wm2000->anc_download_size = fw->size + 2;
    wm2000->anc_download = devm_kzalloc(&i2c->dev,
                        wm2000->anc_download_size,
                        GFP_KERNEL);
    if (wm2000->anc_download == NULL) {
        dev_err(&i2c->dev, "Out of memory\n");
        ret = -ENOMEM;
        goto err_supplies;
    }

    wm2000->anc_download[0] = 0x80;
    wm2000->anc_download[1] = 0x00;
    memcpy(wm2000->anc_download + 2, fw->data, fw->size);

    wm2000->anc_eng_ena = 1;
    wm2000->anc_active = 1;
    wm2000->spk_ena = 1;
    wm2000->i2c = i2c;

    wm2000_reset(wm2000);

    ret = snd_soc_register_codec(&i2c->dev, &soc_codec_dev_wm2000, NULL, 0);

err_supplies:
    regulator_bulk_disable(WM2000_NUM_SUPPLIES, wm2000->supplies);

out:
    release_firmware(fw);
    return ret;
}

static __devexit int wm2000_i2c_remove(struct i2c_client *i2c)
{
    snd_soc_unregister_codec(&i2c->dev);

    return 0;
}

static const struct i2c_device_id wm2000_i2c_id[] = {
    { "wm2000", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, wm2000_i2c_id);

static struct i2c_driver wm2000_i2c_driver = {
    .driver = {
        .name = "wm2000",
        .owner = THIS_MODULE,
    },
    .probe = wm2000_i2c_probe,
    .remove = __devexit_p(wm2000_i2c_remove),
    .id_table = wm2000_i2c_id,
};

module_i2c_driver(wm2000_i2c_driver);

MODULE_DESCRIPTION("ASoC WM2000 driver");
MODULE_AUTHOR("Mark Brown <[email protected]>");
MODULE_LICENSE("GPL");