// SPDX-License-Identifier: GPL-2.0
/*
 * MAX9759 Amplifier Driver
 *
 * Copyright (c) 2017 BayLibre, SAS.
 * Author: Neil Armstrong <narmstrong@baylibre.com>
 */

#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <sound/soc.h>
#include <sound/soc-dapm.h>
#include <sound/tlv.h>

#define DRV_NAME "max9759"

struct max9759 {
        struct gpio_desc *gpiod_shutdown;
        struct gpio_desc *gpiod_mute;
        struct gpio_descs *gpiod_gain;
        bool is_mute;
        unsigned int gain;
};

static int pga_event(struct snd_soc_dapm_widget *w,
                     struct snd_kcontrol *control, int event)
{
        struct snd_soc_component *c = snd_soc_dapm_to_component(w->dapm);
        struct max9759 *priv = snd_soc_component_get_drvdata(c);

        if (SND_SOC_DAPM_EVENT_ON(event))
                gpiod_set_value_cansleep(priv->gpiod_shutdown, 0);
        else
                gpiod_set_value_cansleep(priv->gpiod_shutdown, 1);

        return 0;
}

/* From 6dB to 24dB in steps of 6dB */
static const DECLARE_TLV_DB_SCALE(speaker_gain_tlv, 600, 600, 0);

static int speaker_gain_control_get(struct snd_kcontrol *kcontrol,
                                    struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct max9759 *priv = snd_soc_component_get_drvdata(c);

        ucontrol->value.integer.value[0] = priv->gain;

        return 0;
}

static const bool speaker_gain_table[4][2] = {
        /* G1, G2 */
        {true, true},   /* +6dB */
        {false, true},  /* +12dB */
        {true, false},  /* +18dB */
        {false, false}, /* +24dB */
};

static int speaker_gain_control_put(struct snd_kcontrol *kcontrol,
                                    struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct max9759 *priv = snd_soc_component_get_drvdata(c);

        if (ucontrol->value.integer.value[0] < 0 ||
            ucontrol->value.integer.value[0] > 3)
                return -EINVAL;

        priv->gain = ucontrol->value.integer.value[0];

        /* G1 */
        gpiod_set_value_cansleep(priv->gpiod_gain->desc[0],
                                 speaker_gain_table[priv->gain][0]);
        /* G2 */
        gpiod_set_value_cansleep(priv->gpiod_gain->desc[1],
                                 speaker_gain_table[priv->gain][1]);

        return 1;
}

static int speaker_mute_get(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct max9759 *priv = snd_soc_component_get_drvdata(c);

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

        return 0;
}

static int speaker_mute_put(struct snd_kcontrol *kcontrol,
                            struct snd_ctl_elem_value *ucontrol)
{
        struct snd_soc_component *c = snd_kcontrol_chip(kcontrol);
        struct max9759 *priv = snd_soc_component_get_drvdata(c);

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

        gpiod_set_value_cansleep(priv->gpiod_mute, priv->is_mute);

        return 1;
}

static const struct snd_kcontrol_new max9759_dapm_controls[] = {
        SOC_SINGLE_EXT_TLV("Speaker Gain Volume", 0, 0, 3, 0,
                           speaker_gain_control_get, speaker_gain_control_put,
                           speaker_gain_tlv),
        SOC_SINGLE_BOOL_EXT("Playback Switch", 0,
                            speaker_mute_get, speaker_mute_put),
};

static const struct snd_soc_dapm_widget max9759_dapm_widgets[] = {
        SND_SOC_DAPM_INPUT("INL"),
        SND_SOC_DAPM_INPUT("INR"),
        SND_SOC_DAPM_PGA_E("PGA", SND_SOC_NOPM, 0, 0, NULL, 0, pga_event,
                           (SND_SOC_DAPM_PRE_PMU | SND_SOC_DAPM_POST_PMD)),
        SND_SOC_DAPM_OUTPUT("OUTL"),
        SND_SOC_DAPM_OUTPUT("OUTR"),
};

static const struct snd_soc_dapm_route max9759_dapm_routes[] = {
        { "PGA", NULL, "INL" },
        { "PGA", NULL, "INR" },
        { "OUTL", NULL, "PGA" },
        { "OUTR", NULL, "PGA" },
};

static const struct snd_soc_component_driver max9759_component_driver = {
        .controls               = max9759_dapm_controls,
        .num_controls           = ARRAY_SIZE(max9759_dapm_controls),
        .dapm_widgets           = max9759_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(max9759_dapm_widgets),
        .dapm_routes            = max9759_dapm_routes,
        .num_dapm_routes        = ARRAY_SIZE(max9759_dapm_routes),
};

static int max9759_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct max9759 *priv;

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

        platform_set_drvdata(pdev, priv);

        priv->gpiod_shutdown = devm_gpiod_get(dev, "shutdown", GPIOD_OUT_HIGH);
        if (IS_ERR(priv->gpiod_shutdown))
                return dev_err_probe(dev, PTR_ERR(priv->gpiod_shutdown),
                                     "Failed to get 'shutdown' gpio");

        priv->gpiod_mute = devm_gpiod_get(dev, "mute", GPIOD_OUT_HIGH);
        if (IS_ERR(priv->gpiod_mute))
                return dev_err_probe(dev, PTR_ERR(priv->gpiod_mute),
                                     "Failed to get 'mute' gpio");
        priv->is_mute = true;

        priv->gpiod_gain = devm_gpiod_get_array(dev, "gain", GPIOD_OUT_HIGH);
        if (IS_ERR(priv->gpiod_gain))
                return dev_err_probe(dev, PTR_ERR(priv->gpiod_gain),
                                     "Failed to get 'gain' gpios");
        priv->gain = 0;

        if (priv->gpiod_gain->ndescs != 2) {
                dev_err(dev, "Invalid 'gain' gpios count: %d",
                        priv->gpiod_gain->ndescs);
                return -EINVAL;
        }

        return devm_snd_soc_register_component(dev, &max9759_component_driver,
                                               NULL, 0);
}

#ifdef CONFIG_OF
static const struct of_device_id max9759_ids[] = {
        { .compatible = "maxim,max9759", },
        { }
};
MODULE_DEVICE_TABLE(of, max9759_ids);
#endif

static struct platform_driver max9759_driver = {
        .driver = {
                .name = DRV_NAME,
                .of_match_table = of_match_ptr(max9759_ids),
        },
        .probe = max9759_probe,
};

module_platform_driver(max9759_driver);

MODULE_DESCRIPTION("ASoC MAX9759 amplifier driver");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
MODULE_LICENSE("GPL");