root/sound/soc/codecs/pcm1789.c
// SPDX-License-Identifier: GPL-2.0
// Audio driver for PCM1789
// Copyright (C) 2018 Bootlin
// Mylène Josserand <mylene.josserand@bootlin.com>

#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/workqueue.h>

#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/tlv.h>

#include "pcm1789.h"

#define PCM1789_MUTE_CONTROL    0x10
#define PCM1789_FMT_CONTROL     0x11
#define PCM1789_SOFT_MUTE       0x14
#define PCM1789_DAC_VOL_LEFT    0x18
#define PCM1789_DAC_VOL_RIGHT   0x19

#define PCM1789_FMT_MASK        0x07
#define PCM1789_MUTE_MASK       0x03
#define PCM1789_MUTE_SRET       0x06

struct pcm1789_private {
        struct regmap *regmap;
        unsigned int format;
        unsigned int rate;
        struct gpio_desc *reset;
        struct work_struct work;
        struct device *dev;
};

static const struct reg_default pcm1789_reg_defaults[] = {
        { PCM1789_FMT_CONTROL, 0x00 },
        { PCM1789_SOFT_MUTE, 0x00 },
        { PCM1789_DAC_VOL_LEFT, 0xff },
        { PCM1789_DAC_VOL_RIGHT, 0xff },
};

static bool pcm1789_accessible_reg(struct device *dev, unsigned int reg)
{
        return reg >= PCM1789_MUTE_CONTROL && reg <= PCM1789_DAC_VOL_RIGHT;
}

static bool pcm1789_writeable_reg(struct device *dev, unsigned int reg)
{
        return pcm1789_accessible_reg(dev, reg);
}

static int pcm1789_set_dai_fmt(struct snd_soc_dai *codec_dai,
                               unsigned int format)
{
        struct snd_soc_component *component = codec_dai->component;
        struct pcm1789_private *priv = snd_soc_component_get_drvdata(component);

        priv->format = format;

        return 0;
}

static int pcm1789_mute(struct snd_soc_dai *codec_dai, int mute, int direction)
{
        struct snd_soc_component *component = codec_dai->component;
        struct pcm1789_private *priv = snd_soc_component_get_drvdata(component);

        return regmap_update_bits(priv->regmap, PCM1789_SOFT_MUTE,
                                  PCM1789_MUTE_MASK,
                                  mute ? 0 : PCM1789_MUTE_MASK);
}

static int pcm1789_hw_params(struct snd_pcm_substream *substream,
                             struct snd_pcm_hw_params *params,
                             struct snd_soc_dai *codec_dai)
{
        struct snd_soc_component *component = codec_dai->component;
        struct pcm1789_private *priv = snd_soc_component_get_drvdata(component);
        int val = 0, ret;

        priv->rate = params_rate(params);

        switch (priv->format & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_RIGHT_J:
                switch (params_width(params)) {
                case 24:
                        val = 2;
                        break;
                case 16:
                        val = 3;
                        break;
                default:
                        return -EINVAL;
                }
                break;
        case SND_SOC_DAIFMT_I2S:
                switch (params_width(params)) {
                case 16:
                case 24:
                case 32:
                        val = 0;
                        break;
                default:
                        return -EINVAL;
                }
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                switch (params_width(params)) {
                case 16:
                case 24:
                case 32:
                        val = 1;
                        break;
                default:
                        return -EINVAL;
                }
                break;
        default:
                dev_err(component->dev, "Invalid DAI format\n");
                return -EINVAL;
        }

        ret = regmap_update_bits(priv->regmap, PCM1789_FMT_CONTROL,
                                 PCM1789_FMT_MASK, val);
        if (ret < 0)
                return ret;

        return 0;
}

static void pcm1789_work_queue(struct work_struct *work)
{
        struct pcm1789_private *priv = container_of(work,
                                                    struct pcm1789_private,
                                                    work);

        /* Perform a software reset to remove codec from desynchronized state */
        if (regmap_update_bits(priv->regmap, PCM1789_MUTE_CONTROL,
                               0x3 << PCM1789_MUTE_SRET, 0) < 0)
                dev_err(priv->dev, "Error while setting SRET");
}

static int pcm1789_trigger(struct snd_pcm_substream *substream, int cmd,
                           struct snd_soc_dai *dai)
{
        struct snd_soc_component *component = dai->component;
        struct pcm1789_private *priv = snd_soc_component_get_drvdata(component);
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                schedule_work(&priv->work);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

static const struct snd_soc_dai_ops pcm1789_dai_ops = {
        .set_fmt        = pcm1789_set_dai_fmt,
        .hw_params      = pcm1789_hw_params,
        .mute_stream    = pcm1789_mute,
        .trigger        = pcm1789_trigger,
        .no_capture_mute = 1,
};

static const DECLARE_TLV_DB_SCALE(pcm1789_dac_tlv, -12000, 50, 1);

static const struct snd_kcontrol_new pcm1789_controls[] = {
        SOC_DOUBLE_R_RANGE_TLV("DAC Playback Volume", PCM1789_DAC_VOL_LEFT,
                               PCM1789_DAC_VOL_RIGHT, 0, 0xf, 0xff, 0,
                               pcm1789_dac_tlv),
};

static const struct snd_soc_dapm_widget pcm1789_dapm_widgets[] = {
        SND_SOC_DAPM_OUTPUT("IOUTL+"),
        SND_SOC_DAPM_OUTPUT("IOUTL-"),
        SND_SOC_DAPM_OUTPUT("IOUTR+"),
        SND_SOC_DAPM_OUTPUT("IOUTR-"),
};

static const struct snd_soc_dapm_route pcm1789_dapm_routes[] = {
        { "IOUTL+", NULL, "Playback" },
        { "IOUTL-", NULL, "Playback" },
        { "IOUTR+", NULL, "Playback" },
        { "IOUTR-", NULL, "Playback" },
};

static struct snd_soc_dai_driver pcm1789_dai = {
        .name = "pcm1789-hifi",
        .playback = {
                .stream_name = "Playback",
                .channels_min = 2,
                .channels_max = 2,
                .rates = SNDRV_PCM_RATE_CONTINUOUS,
                .rate_min = 10000,
                .rate_max = 200000,
                .formats = PCM1789_FORMATS,
        },
        .ops = &pcm1789_dai_ops,
};

const struct regmap_config pcm1789_regmap_config = {
        .reg_bits               = 8,
        .val_bits               = 8,
        .max_register           = PCM1789_DAC_VOL_RIGHT,
        .reg_defaults           = pcm1789_reg_defaults,
        .num_reg_defaults       = ARRAY_SIZE(pcm1789_reg_defaults),
        .writeable_reg          = pcm1789_writeable_reg,
        .readable_reg           = pcm1789_accessible_reg,
};
EXPORT_SYMBOL_GPL(pcm1789_regmap_config);

static const struct snd_soc_component_driver soc_component_dev_pcm1789 = {
        .controls               = pcm1789_controls,
        .num_controls           = ARRAY_SIZE(pcm1789_controls),
        .dapm_widgets           = pcm1789_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(pcm1789_dapm_widgets),
        .dapm_routes            = pcm1789_dapm_routes,
        .num_dapm_routes        = ARRAY_SIZE(pcm1789_dapm_routes),
        .idle_bias_on           = 1,
        .use_pmdown_time        = 1,
        .endianness             = 1,
};

int pcm1789_common_init(struct device *dev, struct regmap *regmap)
{
        struct pcm1789_private *pcm1789;

        pcm1789 = devm_kzalloc(dev, sizeof(struct pcm1789_private),
                               GFP_KERNEL);
        if (!pcm1789)
                return -ENOMEM;

        pcm1789->regmap = regmap;
        pcm1789->dev = dev;
        dev_set_drvdata(dev, pcm1789);

        pcm1789->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
        if (IS_ERR(pcm1789->reset))
                return PTR_ERR(pcm1789->reset);

        gpiod_set_value_cansleep(pcm1789->reset, 0);
        msleep(300);

        INIT_WORK(&pcm1789->work, pcm1789_work_queue);

        return devm_snd_soc_register_component(dev, &soc_component_dev_pcm1789,
                                               &pcm1789_dai, 1);
}
EXPORT_SYMBOL_GPL(pcm1789_common_init);

void pcm1789_common_exit(struct device *dev)
{
        struct pcm1789_private *priv = dev_get_drvdata(dev);

        flush_work(&priv->work);
}
EXPORT_SYMBOL_GPL(pcm1789_common_exit);

MODULE_DESCRIPTION("ASoC PCM1789 driver");
MODULE_AUTHOR("Mylène Josserand <mylene.josserand@free-electrons.com>");
MODULE_LICENSE("GPL");