max9768.c

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/*
 * MAX9768 AMP driver
 *
 * Copyright (C) 2011, 2012 by Wolfram Sang, Pengutronix e.K.
 *
 * 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; version 2 of the License.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/gpio.h>
#include <linux/regmap.h>

#include <sound/core.h>
#include <sound/soc.h>
#include <sound/tlv.h>
#include <sound/max9768.h>

/* "Registers" */
#define MAX9768_VOL 0
#define MAX9768_CTRL 3

/* Commands */
#define MAX9768_CTRL_PWM 0x15
#define MAX9768_CTRL_FILTERLESS 0x16

struct max9768 {
    struct regmap *regmap;
    int mute_gpio;
    int shdn_gpio;
    u32 flags;
};

static struct reg_default max9768_default_regs[] = {
    { 0, 0 },
    { 3,  MAX9768_CTRL_FILTERLESS},
};

static int max9768_get_gpio(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct max9768 *max9768 = snd_soc_codec_get_drvdata(codec);
    int val = gpio_get_value_cansleep(max9768->mute_gpio);

    ucontrol->value.integer.value[0] = !val;

    return 0;
}

static int max9768_set_gpio(struct snd_kcontrol *kcontrol,
    struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct max9768 *max9768 = snd_soc_codec_get_drvdata(codec);

    gpio_set_value_cansleep(max9768->mute_gpio, !ucontrol->value.integer.value[0]);

    return 0;
}

static const unsigned int volume_tlv[] = {
    TLV_DB_RANGE_HEAD(43),
    0, 0, TLV_DB_SCALE_ITEM(-16150, 0, 0),
    1, 1, TLV_DB_SCALE_ITEM(-9280, 0, 0),
    2, 2, TLV_DB_SCALE_ITEM(-9030, 0, 0),
    3, 3, TLV_DB_SCALE_ITEM(-8680, 0, 0),
    4, 4, TLV_DB_SCALE_ITEM(-8430, 0, 0),
    5, 5, TLV_DB_SCALE_ITEM(-8080, 0, 0),
    6, 6, TLV_DB_SCALE_ITEM(-7830, 0, 0),
    7, 7, TLV_DB_SCALE_ITEM(-7470, 0, 0),
    8, 8, TLV_DB_SCALE_ITEM(-7220, 0, 0),
    9, 9, TLV_DB_SCALE_ITEM(-6870, 0, 0),
    10, 10, TLV_DB_SCALE_ITEM(-6620, 0, 0),
    11, 11, TLV_DB_SCALE_ITEM(-6270, 0, 0),
    12, 12, TLV_DB_SCALE_ITEM(-6020, 0, 0),
    13, 13, TLV_DB_SCALE_ITEM(-5670, 0, 0),
    14, 14, TLV_DB_SCALE_ITEM(-5420, 0, 0),
    15, 17, TLV_DB_SCALE_ITEM(-5060, 250, 0),
    18, 18, TLV_DB_SCALE_ITEM(-4370, 0, 0),
    19, 19, TLV_DB_SCALE_ITEM(-4210, 0, 0),
    20, 20, TLV_DB_SCALE_ITEM(-3960, 0, 0),
    21, 21, TLV_DB_SCALE_ITEM(-3760, 0, 0),
    22, 22, TLV_DB_SCALE_ITEM(-3600, 0, 0),
    23, 23, TLV_DB_SCALE_ITEM(-3340, 0, 0),
    24, 24, TLV_DB_SCALE_ITEM(-3150, 0, 0),
    25, 25, TLV_DB_SCALE_ITEM(-2980, 0, 0),
    26, 26, TLV_DB_SCALE_ITEM(-2720, 0, 0),
    27, 27, TLV_DB_SCALE_ITEM(-2520, 0, 0),
    28, 30, TLV_DB_SCALE_ITEM(-2350, 190, 0),
    31, 31, TLV_DB_SCALE_ITEM(-1750, 0, 0),
    32, 34, TLV_DB_SCALE_ITEM(-1640, 100, 0),
    35, 37, TLV_DB_SCALE_ITEM(-1310, 110, 0),
    38, 39, TLV_DB_SCALE_ITEM(-990, 100, 0),
    40, 40, TLV_DB_SCALE_ITEM(-710, 0, 0),
    41, 41, TLV_DB_SCALE_ITEM(-600, 0, 0),
    42, 42, TLV_DB_SCALE_ITEM(-500, 0, 0),
    43, 43, TLV_DB_SCALE_ITEM(-340, 0, 0),
    44, 44, TLV_DB_SCALE_ITEM(-190, 0, 0),
    45, 45, TLV_DB_SCALE_ITEM(-50, 0, 0),
    46, 46, TLV_DB_SCALE_ITEM(50, 0, 0),
    47, 50, TLV_DB_SCALE_ITEM(120, 40, 0),
    51, 57, TLV_DB_SCALE_ITEM(290, 50, 0),
    58, 58, TLV_DB_SCALE_ITEM(650, 0, 0),
    59, 62, TLV_DB_SCALE_ITEM(700, 60, 0),
    63, 63, TLV_DB_SCALE_ITEM(950, 0, 0),
};

static const struct snd_kcontrol_new max9768_volume[] = {
    SOC_SINGLE_TLV("Playback Volume", MAX9768_VOL, 0, 63, 0, volume_tlv),
};

static const struct snd_kcontrol_new max9768_mute[] = {
    SOC_SINGLE_BOOL_EXT("Playback Switch", 0, max9768_get_gpio, max9768_set_gpio),
};

static int max9768_probe(struct snd_soc_codec *codec)
{
    struct max9768 *max9768 = snd_soc_codec_get_drvdata(codec);
    int ret;

    codec->control_data = max9768->regmap;
    ret = snd_soc_codec_set_cache_io(codec, 2, 6, SND_SOC_REGMAP);
    if (ret)
        return ret;

    if (max9768->flags & MAX9768_FLAG_CLASSIC_PWM) {
        ret = snd_soc_write(codec, MAX9768_CTRL, MAX9768_CTRL_PWM);
        if (ret)
            return ret;
    }

    if (gpio_is_valid(max9768->mute_gpio)) {
        ret = snd_soc_add_codec_controls(codec, max9768_mute,
                ARRAY_SIZE(max9768_mute));
        if (ret)
            return ret;
    }

    return 0;
}

static struct snd_soc_codec_driver max9768_codec_driver = {
    .probe = max9768_probe,
    .controls = max9768_volume,
    .num_controls = ARRAY_SIZE(max9768_volume),
};

static const struct regmap_config max9768_i2c_regmap_config = {
    .reg_bits = 2,
    .val_bits = 6,
    .max_register = 3,
    .reg_defaults = max9768_default_regs,
    .num_reg_defaults = ARRAY_SIZE(max9768_default_regs),
    .cache_type = REGCACHE_RBTREE,
};

static int __devinit max9768_i2c_probe(struct i2c_client *client,
    const struct i2c_device_id *id)
{
    struct max9768 *max9768;
    struct max9768_pdata *pdata = client->dev.platform_data;
    int err;

    max9768 = devm_kzalloc(&client->dev, sizeof(*max9768), GFP_KERNEL);
    if (!max9768)
        return -ENOMEM;

    if (pdata) {
        /* Mute on powerup to avoid clicks */
        err = gpio_request_one(pdata->mute_gpio, GPIOF_INIT_HIGH, "MAX9768 Mute");
        max9768->mute_gpio = err ?: pdata->mute_gpio;

        /* Activate chip by releasing shutdown, enables I2C */
        err = gpio_request_one(pdata->shdn_gpio, GPIOF_INIT_HIGH, "MAX9768 Shutdown");
        max9768->shdn_gpio = err ?: pdata->shdn_gpio;

        max9768->flags = pdata->flags;
    } else {
        max9768->shdn_gpio = -EINVAL;
        max9768->mute_gpio = -EINVAL;
    }

    i2c_set_clientdata(client, max9768);

    max9768->regmap = regmap_init_i2c(client, &max9768_i2c_regmap_config);
    if (IS_ERR(max9768->regmap)) {
        err = PTR_ERR(max9768->regmap);
        goto err_gpio_free;
    }

    err = snd_soc_register_codec(&client->dev, &max9768_codec_driver, NULL, 0);
    if (err)
        goto err_regmap_free;

    return 0;

 err_regmap_free:
    regmap_exit(max9768->regmap);
 err_gpio_free:
    if (gpio_is_valid(max9768->shdn_gpio))
        gpio_free(max9768->shdn_gpio);
    if (gpio_is_valid(max9768->mute_gpio))
        gpio_free(max9768->mute_gpio);

    return err;
}

static int __devexit max9768_i2c_remove(struct i2c_client *client)
{
    struct max9768 *max9768 = i2c_get_clientdata(client);

    snd_soc_unregister_codec(&client->dev);
    regmap_exit(max9768->regmap);

    if (gpio_is_valid(max9768->shdn_gpio))
        gpio_free(max9768->shdn_gpio);
    if (gpio_is_valid(max9768->mute_gpio))
        gpio_free(max9768->mute_gpio);

    return 0;
}

static const struct i2c_device_id max9768_i2c_id[] = {
    { "max9768", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, max9768_i2c_id);

static struct i2c_driver max9768_i2c_driver = {
    .driver = {
        .name = "max9768",
        .owner = THIS_MODULE,
    },
    .probe = max9768_i2c_probe,
    .remove = __devexit_p(max9768_i2c_remove),
    .id_table = max9768_i2c_id,
};
module_i2c_driver(max9768_i2c_driver);

MODULE_AUTHOR("Wolfram Sang <[email protected]>");
MODULE_DESCRIPTION("ASoC MAX9768 amplifier driver");
MODULE_LICENSE("GPL v2");