// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2021 Stephan Gerhold
 *
 * Register definitions/sequences taken from various tfa98xx kernel drivers:
 * Copyright (C) 2014-2020 NXP Semiconductors, All Rights Reserved.
 * Copyright (C) 2013 Sony Mobile Communications Inc.
 */

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <sound/soc.h>

#define TFA989X_STATUSREG               0x00
#define TFA989X_BATTERYVOLTAGE          0x01
#define TFA989X_TEMPERATURE             0x02
#define TFA989X_REVISIONNUMBER          0x03
#define TFA989X_REVISIONNUMBER_REV_MSK  GENMASK(7, 0)   /* device revision */
#define TFA989X_I2SREG                  0x04
#define TFA989X_I2SREG_RCV              2       /* receiver mode */
#define TFA989X_I2SREG_CHSA             6       /* amplifier input select */
#define TFA989X_I2SREG_CHSA_MSK         GENMASK(7, 6)
#define TFA989X_I2SREG_I2SSR            12      /* sample rate */
#define TFA989X_I2SREG_I2SSR_MSK        GENMASK(15, 12)
#define TFA989X_BAT_PROT                0x05
#define TFA989X_AUDIO_CTR               0x06
#define TFA989X_DCDCBOOST               0x07
#define TFA989X_SPKR_CALIBRATION        0x08
#define TFA989X_SYS_CTRL                0x09
#define TFA989X_SYS_CTRL_PWDN           0       /* power down */
#define TFA989X_SYS_CTRL_I2CR           1       /* I2C reset */
#define TFA989X_SYS_CTRL_CFE            2       /* enable CoolFlux DSP */
#define TFA989X_SYS_CTRL_AMPE           3       /* enable amplifier */
#define TFA989X_SYS_CTRL_DCA            4       /* enable boost */
#define TFA989X_SYS_CTRL_SBSL           5       /* DSP configured */
#define TFA989X_SYS_CTRL_AMPC           6       /* amplifier enabled by DSP */
#define TFA989X_I2S_SEL_REG             0x0a
#define TFA989X_I2S_SEL_REG_SPKR_MSK    GENMASK(10, 9)  /* speaker impedance */
#define TFA989X_I2S_SEL_REG_DCFG_MSK    GENMASK(14, 11) /* DCDC compensation */
#define TFA989X_HIDE_UNHIDE_KEY 0x40
#define TFA989X_PWM_CONTROL             0x41
#define TFA989X_CURRENTSENSE1           0x46
#define TFA989X_CURRENTSENSE2           0x47
#define TFA989X_CURRENTSENSE3           0x48
#define TFA989X_CURRENTSENSE4           0x49

#define TFA9890_REVISION                0x80
#define TFA9895_REVISION                0x12
#define TFA9897_REVISION                0x97

struct tfa989x_rev {
        unsigned int rev;
        int (*init)(struct regmap *regmap);
};

struct tfa989x {
        const struct tfa989x_rev *rev;
        struct regulator *vddd_supply;
        struct gpio_desc *rcv_gpiod;
};

static bool tfa989x_writeable_reg(struct device *dev, unsigned int reg)
{
        return reg > TFA989X_REVISIONNUMBER;
}

static bool tfa989x_volatile_reg(struct device *dev, unsigned int reg)
{
        return reg < TFA989X_REVISIONNUMBER;
}

static const struct regmap_config tfa989x_regmap = {
        .reg_bits = 8,
        .val_bits = 16,

        .writeable_reg  = tfa989x_writeable_reg,
        .volatile_reg   = tfa989x_volatile_reg,
        .cache_type     = REGCACHE_RBTREE,
};

static const char * const chsa_text[] = { "Left", "Right", /* "DSP" */ };
static SOC_ENUM_SINGLE_DECL(chsa_enum, TFA989X_I2SREG, TFA989X_I2SREG_CHSA, chsa_text);
static const struct snd_kcontrol_new chsa_mux = SOC_DAPM_ENUM("Amp Input", chsa_enum);

static const struct snd_soc_dapm_widget tfa989x_dapm_widgets[] = {
        SND_SOC_DAPM_OUTPUT("OUT"),
        SND_SOC_DAPM_SUPPLY("POWER", TFA989X_SYS_CTRL, TFA989X_SYS_CTRL_PWDN, 1, NULL, 0),
        SND_SOC_DAPM_OUT_DRV("AMPE", TFA989X_SYS_CTRL, TFA989X_SYS_CTRL_AMPE, 0, NULL, 0),

        SND_SOC_DAPM_MUX("Amp Input", SND_SOC_NOPM, 0, 0, &chsa_mux),
        SND_SOC_DAPM_AIF_IN("AIFINL", "HiFi Playback", 0, SND_SOC_NOPM, 0, 0),
        SND_SOC_DAPM_AIF_IN("AIFINR", "HiFi Playback", 1, SND_SOC_NOPM, 0, 0),
};

static const struct snd_soc_dapm_route tfa989x_dapm_routes[] = {
        {"OUT", NULL, "AMPE"},
        {"AMPE", NULL, "POWER"},
        {"AMPE", NULL, "Amp Input"},
        {"Amp Input", "Left", "AIFINL"},
        {"Amp Input", "Right", "AIFINR"},
};

static int tfa989x_put_mode(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
        struct tfa989x *tfa989x = snd_soc_component_get_drvdata(component);

        gpiod_set_value_cansleep(tfa989x->rcv_gpiod, ucontrol->value.enumerated.item[0]);

        return snd_soc_put_enum_double(kcontrol, ucontrol);
}

static const char * const mode_text[] = { "Speaker", "Receiver" };
static SOC_ENUM_SINGLE_DECL(mode_enum, TFA989X_I2SREG, TFA989X_I2SREG_RCV, mode_text);
static const struct snd_kcontrol_new tfa989x_mode_controls[] = {
        SOC_ENUM_EXT("Mode", mode_enum, snd_soc_get_enum_double, tfa989x_put_mode),
};

static int tfa989x_probe(struct snd_soc_component *component)
{
        struct tfa989x *tfa989x = snd_soc_component_get_drvdata(component);

        if (tfa989x->rev->rev == TFA9897_REVISION)
                return snd_soc_add_component_controls(component, tfa989x_mode_controls,
                                                      ARRAY_SIZE(tfa989x_mode_controls));

        return 0;
}

static const struct snd_soc_component_driver tfa989x_component = {
        .probe                  = tfa989x_probe,
        .dapm_widgets           = tfa989x_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(tfa989x_dapm_widgets),
        .dapm_routes            = tfa989x_dapm_routes,
        .num_dapm_routes        = ARRAY_SIZE(tfa989x_dapm_routes),
        .use_pmdown_time        = 1,
        .endianness             = 1,
};

static const unsigned int tfa989x_rates[] = {
        8000, 11025, 12000, 16000, 22050, 24000, 32000, 44100, 48000
};

static int tfa989x_find_sample_rate(unsigned int rate)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(tfa989x_rates); ++i)
                if (tfa989x_rates[i] == rate)
                        return i;

        return -EINVAL;
}

static int tfa989x_hw_params(struct snd_pcm_substream *substream,
                             struct snd_pcm_hw_params *params,
                             struct snd_soc_dai *dai)
{
        struct snd_soc_component *component = dai->component;
        int sr;

        sr = tfa989x_find_sample_rate(params_rate(params));
        if (sr < 0)
                return sr;

        return snd_soc_component_update_bits(component, TFA989X_I2SREG,
                                             TFA989X_I2SREG_I2SSR_MSK,
                                             sr << TFA989X_I2SREG_I2SSR);
}

static const struct snd_soc_dai_ops tfa989x_dai_ops = {
        .hw_params = tfa989x_hw_params,
};

static struct snd_soc_dai_driver tfa989x_dai = {
        .name = "tfa989x-hifi",
        .playback = {
                .stream_name    = "HiFi Playback",
                .formats        = SNDRV_PCM_FMTBIT_S16_LE,
                .rates          = SNDRV_PCM_RATE_8000_48000,
                .rate_min       = 8000,
                .rate_max       = 48000,
                .channels_min   = 1,
                .channels_max   = 2,
        },
        .ops = &tfa989x_dai_ops,
};

static int tfa9890_init(struct regmap *regmap)
{
        int ret;

        /* temporarily allow access to hidden registers */
        ret = regmap_write(regmap, TFA989X_HIDE_UNHIDE_KEY, 0x5a6b);
        if (ret)
                return ret;

        /* update PLL registers */
        ret = regmap_set_bits(regmap, 0x59, 0x3);
        if (ret)
                return ret;

        /* hide registers again */
        ret = regmap_write(regmap, TFA989X_HIDE_UNHIDE_KEY, 0x0000);
        if (ret)
                return ret;

        return regmap_write(regmap, TFA989X_CURRENTSENSE2, 0x7BE1);
}

static const struct tfa989x_rev tfa9890_rev = {
        .rev    = TFA9890_REVISION,
        .init   = tfa9890_init,
};

static const struct reg_sequence tfa9895_reg_init[] = {
        /* some other registers must be set for optimal amplifier behaviour */
        { TFA989X_BAT_PROT, 0x13ab },
        { TFA989X_AUDIO_CTR, 0x001f },

        /* peak voltage protection is always on, but may be written */
        { TFA989X_SPKR_CALIBRATION, 0x3c4e },

        /* TFA989X_SYSCTRL_DCA = 0 */
        { TFA989X_SYS_CTRL, 0x024d },
        { TFA989X_PWM_CONTROL, 0x0308 },
        { TFA989X_CURRENTSENSE4, 0x0e82 },
};

static int tfa9895_init(struct regmap *regmap)
{
        return regmap_multi_reg_write(regmap, tfa9895_reg_init,
                                      ARRAY_SIZE(tfa9895_reg_init));
}

static const struct tfa989x_rev tfa9895_rev = {
        .rev    = TFA9895_REVISION,
        .init   = tfa9895_init,
};

static int tfa9897_init(struct regmap *regmap)
{
        int ret;

        /* Reduce slewrate by clearing iddqtestbst to avoid booster damage */
        ret = regmap_write(regmap, TFA989X_CURRENTSENSE3, 0x0300);
        if (ret)
                return ret;

        /* Enable clipping */
        ret = regmap_clear_bits(regmap, TFA989X_CURRENTSENSE4, 0x1);
        if (ret)
                return ret;

        /* Set required TDM configuration */
        return regmap_write(regmap, 0x14, 0x0);
}

static const struct tfa989x_rev tfa9897_rev = {
        .rev    = TFA9897_REVISION,
        .init   = tfa9897_init,
};

/*
 * Note: At the moment this driver bypasses the "CoolFlux DSP" built into the
 * TFA989X amplifiers. Unfortunately, there seems to be absolutely
 * no documentation for it - the public "short datasheets" do not provide
 * any information about the DSP or available registers.
 *
 * Usually the TFA989X amplifiers are configured through proprietary userspace
 * libraries. There are also some (rather complex) kernel drivers but even those
 * rely on obscure firmware blobs for configuration (so-called "containers").
 * They seem to contain different "profiles" with tuned speaker settings, sample
 * rates and volume steps (which would be better exposed as separate ALSA mixers).
 *
 * Bypassing the DSP disables volume control (and perhaps some speaker
 * optimization?), but at least allows using the speaker without obscure
 * kernel drivers and firmware.
 *
 * Ideally NXP (or now Goodix) should release proper documentation for these
 * amplifiers so that support for the "CoolFlux DSP" can be implemented properly.
 */
static int tfa989x_dsp_bypass(struct regmap *regmap)
{
        int ret;

        /* Clear CHSA to bypass DSP and take input from I2S 1 left channel */
        ret = regmap_clear_bits(regmap, TFA989X_I2SREG, TFA989X_I2SREG_CHSA_MSK);
        if (ret)
                return ret;

        /* Set DCDC compensation to off and speaker impedance to 8 ohm */
        ret = regmap_update_bits(regmap, TFA989X_I2S_SEL_REG,
                                 TFA989X_I2S_SEL_REG_DCFG_MSK |
                                 TFA989X_I2S_SEL_REG_SPKR_MSK,
                                 TFA989X_I2S_SEL_REG_SPKR_MSK);
        if (ret)
                return ret;

        /* Set DCDC to follower mode and disable CoolFlux DSP */
        return regmap_clear_bits(regmap, TFA989X_SYS_CTRL,
                                 BIT(TFA989X_SYS_CTRL_DCA) |
                                 BIT(TFA989X_SYS_CTRL_CFE) |
                                 BIT(TFA989X_SYS_CTRL_AMPC));
}

static void tfa989x_regulator_disable(void *data)
{
        struct tfa989x *tfa989x = data;

        regulator_disable(tfa989x->vddd_supply);
}

static int tfa989x_i2c_probe(struct i2c_client *i2c)
{
        struct device *dev = &i2c->dev;
        const struct tfa989x_rev *rev;
        struct tfa989x *tfa989x;
        struct regmap *regmap;
        unsigned int val;
        int ret;

        rev = device_get_match_data(dev);
        if (!rev) {
                dev_err(dev, "unknown device revision\n");
                return -ENODEV;
        }

        tfa989x = devm_kzalloc(dev, sizeof(*tfa989x), GFP_KERNEL);
        if (!tfa989x)
                return -ENOMEM;

        tfa989x->rev = rev;
        i2c_set_clientdata(i2c, tfa989x);

        tfa989x->vddd_supply = devm_regulator_get(dev, "vddd");
        if (IS_ERR(tfa989x->vddd_supply))
                return dev_err_probe(dev, PTR_ERR(tfa989x->vddd_supply),
                                     "Failed to get vddd regulator\n");

        if (tfa989x->rev->rev == TFA9897_REVISION) {
                tfa989x->rcv_gpiod = devm_gpiod_get_optional(dev, "rcv", GPIOD_OUT_LOW);
                if (IS_ERR(tfa989x->rcv_gpiod))
                        return PTR_ERR(tfa989x->rcv_gpiod);
        }

        regmap = devm_regmap_init_i2c(i2c, &tfa989x_regmap);
        if (IS_ERR(regmap))
                return PTR_ERR(regmap);

        ret = regulator_enable(tfa989x->vddd_supply);
        if (ret) {
                dev_err(dev, "Failed to enable vddd regulator: %d\n", ret);
                return ret;
        }

        ret = devm_add_action_or_reset(dev, tfa989x_regulator_disable, tfa989x);
        if (ret)
                return ret;

        /* Bypass regcache for reset and init sequence */
        regcache_cache_bypass(regmap, true);

        /* Dummy read to generate i2c clocks, required on some devices */
        regmap_read(regmap, TFA989X_REVISIONNUMBER, &val);

        ret = regmap_read(regmap, TFA989X_REVISIONNUMBER, &val);
        if (ret) {
                dev_err(dev, "failed to read revision number: %d\n", ret);
                return ret;
        }

        val &= TFA989X_REVISIONNUMBER_REV_MSK;
        if (val != rev->rev) {
                dev_err(dev, "invalid revision number, expected %#x, got %#x\n",
                        rev->rev, val);
                return -ENODEV;
        }

        ret = regmap_write(regmap, TFA989X_SYS_CTRL, BIT(TFA989X_SYS_CTRL_I2CR));
        if (ret) {
                dev_err(dev, "failed to reset I2C registers: %d\n", ret);
                return ret;
        }

        ret = rev->init(regmap);
        if (ret) {
                dev_err(dev, "failed to initialize registers: %d\n", ret);
                return ret;
        }

        ret = tfa989x_dsp_bypass(regmap);
        if (ret) {
                dev_err(dev, "failed to enable DSP bypass: %d\n", ret);
                return ret;
        }
        regcache_cache_bypass(regmap, false);

        return devm_snd_soc_register_component(dev, &tfa989x_component,
                                               &tfa989x_dai, 1);
}

static const struct of_device_id tfa989x_of_match[] = {
        { .compatible = "nxp,tfa9890", .data = &tfa9890_rev },
        { .compatible = "nxp,tfa9895", .data = &tfa9895_rev },
        { .compatible = "nxp,tfa9897", .data = &tfa9897_rev },
        { }
};
MODULE_DEVICE_TABLE(of, tfa989x_of_match);

static struct i2c_driver tfa989x_i2c_driver = {
        .driver = {
                .name = "tfa989x",
                .of_match_table = tfa989x_of_match,
        },
        .probe = tfa989x_i2c_probe,
};
module_i2c_driver(tfa989x_i2c_driver);

MODULE_DESCRIPTION("ASoC NXP/Goodix TFA989X (TFA1) driver");
MODULE_AUTHOR("Stephan Gerhold <stephan@gerhold.net>");
MODULE_LICENSE("GPL");