// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2017 BayLibre, SAS.
 * Author: Jerome Brunet <jbrunet@baylibre.com>
 */

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

#define DRV_NAME "simple-amplifier"

struct simple_amp {
        struct gpio_desc *gpiod_enable;
};

static int drv_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 simple_amp *priv = snd_soc_component_get_drvdata(c);
        int val;

        switch (event) {
        case SND_SOC_DAPM_POST_PMU:
                val = 1;
                break;
        case SND_SOC_DAPM_PRE_PMD:
                val = 0;
                break;
        default:
                WARN(1, "Unexpected event");
                return -EINVAL;
        }

        gpiod_set_value_cansleep(priv->gpiod_enable, val);

        return 0;
}

static const struct snd_soc_dapm_widget simple_amp_dapm_widgets[] = {
        SND_SOC_DAPM_INPUT("INL"),
        SND_SOC_DAPM_INPUT("INR"),
        SND_SOC_DAPM_OUT_DRV_E("DRV", SND_SOC_NOPM, 0, 0, NULL, 0, drv_event,
                               (SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD)),
        SND_SOC_DAPM_OUTPUT("OUTL"),
        SND_SOC_DAPM_OUTPUT("OUTR"),
        SND_SOC_DAPM_REGULATOR_SUPPLY("VCC", 20, 0),
};

static const struct snd_soc_dapm_route simple_amp_dapm_routes[] = {
        { "DRV", NULL, "INL" },
        { "DRV", NULL, "INR" },
        { "OUTL", NULL, "VCC" },
        { "OUTR", NULL, "VCC" },
        { "OUTL", NULL, "DRV" },
        { "OUTR", NULL, "DRV" },
};

static const struct snd_soc_component_driver simple_amp_component_driver = {
        .dapm_widgets           = simple_amp_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(simple_amp_dapm_widgets),
        .dapm_routes            = simple_amp_dapm_routes,
        .num_dapm_routes        = ARRAY_SIZE(simple_amp_dapm_routes),
};

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

        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
        if (priv == NULL)
                return -ENOMEM;
        platform_set_drvdata(pdev, priv);

        priv->gpiod_enable = devm_gpiod_get_optional(dev, "enable",
                                                     GPIOD_OUT_LOW);
        if (IS_ERR(priv->gpiod_enable))
                return dev_err_probe(dev, PTR_ERR(priv->gpiod_enable),
                                     "Failed to get 'enable' gpio");

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

#ifdef CONFIG_OF
static const struct of_device_id simple_amp_ids[] = {
        { .compatible = "dioo,dio2125", },
        { .compatible = "simple-audio-amplifier", },
        { }
};
MODULE_DEVICE_TABLE(of, simple_amp_ids);
#endif

static struct platform_driver simple_amp_driver = {
        .driver = {
                .name = DRV_NAME,
                .of_match_table = of_match_ptr(simple_amp_ids),
        },
        .probe = simple_amp_probe,
};

module_platform_driver(simple_amp_driver);

MODULE_DESCRIPTION("ASoC Simple Audio Amplifier driver");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL");