// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) STMicroelectronics SA 2015
 * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>
 *          for STMicroelectronics.
 */

#include <linux/io.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/mfd/syscon.h>

#include <sound/soc.h>
#include <sound/soc-dapm.h>

/* DAC definitions */

/* stih407 DAC registers */
/* sysconf 5041: Audio-Gue-Control */
#define STIH407_AUDIO_GLUE_CTRL 0x000000A4
/* sysconf 5042: Audio-DAC-Control */
#define STIH407_AUDIO_DAC_CTRL 0x000000A8

/* DAC definitions */
#define STIH407_DAC_SOFTMUTE            0x0
#define STIH407_DAC_STANDBY_ANA         0x1
#define STIH407_DAC_STANDBY             0x2

#define STIH407_DAC_SOFTMUTE_MASK       BIT(STIH407_DAC_SOFTMUTE)
#define STIH407_DAC_STANDBY_ANA_MASK    BIT(STIH407_DAC_STANDBY_ANA)
#define STIH407_DAC_STANDBY_MASK        BIT(STIH407_DAC_STANDBY)

/* SPDIF definitions */
#define SPDIF_BIPHASE_ENABLE            0x6
#define SPDIF_BIPHASE_IDLE              0x7

#define SPDIF_BIPHASE_ENABLE_MASK       BIT(SPDIF_BIPHASE_ENABLE)
#define SPDIF_BIPHASE_IDLE_MASK         BIT(SPDIF_BIPHASE_IDLE)

enum {
        STI_SAS_DAI_SPDIF_OUT,
        STI_SAS_DAI_ANALOG_OUT,
};

static const struct reg_default stih407_sas_reg_defaults[] = {
        { STIH407_AUDIO_DAC_CTRL, 0x000000000 },
        { STIH407_AUDIO_GLUE_CTRL, 0x00000040 },
};

struct sti_dac_audio {
        struct regmap *regmap;
        struct regmap *virt_regmap;
        int mclk;
};

struct sti_spdif_audio {
        struct regmap *regmap;
        int mclk;
};

/* device data structure */
struct sti_sas_dev_data {
        const struct regmap_config *regmap;
        const struct snd_soc_dai_ops *dac_ops;  /* DAC function callbacks */
};

/* driver data structure */
struct sti_sas_data {
        struct device *dev;
        const struct sti_sas_dev_data *dev_data;
        struct sti_dac_audio dac;
        struct sti_spdif_audio spdif;
};

/* Read a register from the sysconf reg bank */
static int sti_sas_read_reg(void *context, unsigned int reg,
                            unsigned int *value)
{
        struct sti_sas_data *drvdata = context;
        int status;
        u32 val;

        status = regmap_read(drvdata->dac.regmap, reg, &val);
        *value = (unsigned int)val;

        return status;
}

/* Read a register from the sysconf reg bank */
static int sti_sas_write_reg(void *context, unsigned int reg,
                             unsigned int value)
{
        struct sti_sas_data *drvdata = context;

        return regmap_write(drvdata->dac.regmap, reg, value);
}

static int  sti_sas_init_sas_registers(struct snd_soc_component *component,
                                       struct sti_sas_data *data)
{
        int ret;
        /*
         * DAC and SPDIF are activated by default
         * put them in IDLE to save power
         */

        /* Initialise bi-phase formatter to disabled */
        ret = snd_soc_component_update_bits(component, STIH407_AUDIO_GLUE_CTRL,
                                  SPDIF_BIPHASE_ENABLE_MASK, 0);

        if (!ret)
                /* Initialise bi-phase formatter idle value to 0 */
                ret = snd_soc_component_update_bits(component, STIH407_AUDIO_GLUE_CTRL,
                                          SPDIF_BIPHASE_IDLE_MASK, 0);
        if (ret < 0) {
                dev_err(component->dev, "Failed to update SPDIF registers\n");
                return ret;
        }

        /* Init DAC configuration */
        /* init configuration */
        ret =  snd_soc_component_update_bits(component, STIH407_AUDIO_DAC_CTRL,
                                   STIH407_DAC_STANDBY_MASK,
                                   STIH407_DAC_STANDBY_MASK);

        if (!ret)
                ret = snd_soc_component_update_bits(component, STIH407_AUDIO_DAC_CTRL,
                                          STIH407_DAC_STANDBY_ANA_MASK,
                                          STIH407_DAC_STANDBY_ANA_MASK);
        if (!ret)
                ret = snd_soc_component_update_bits(component, STIH407_AUDIO_DAC_CTRL,
                                          STIH407_DAC_SOFTMUTE_MASK,
                                          STIH407_DAC_SOFTMUTE_MASK);

        if (ret < 0) {
                dev_err(component->dev, "Failed to update DAC registers\n");
                return ret;
        }

        return ret;
}

/*
 * DAC
 */
static int sti_sas_dac_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
{
        /* Sanity check only */
        if ((fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) != SND_SOC_DAIFMT_CBC_CFC) {
                dev_err(dai->component->dev,
                        "%s: ERROR: Unsupported clocking 0x%x\n",
                        __func__, fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK);
                return -EINVAL;
        }

        return 0;
}

static const struct snd_soc_dapm_widget stih407_sas_dapm_widgets[] = {
        SND_SOC_DAPM_OUT_DRV("DAC standby ana", STIH407_AUDIO_DAC_CTRL,
                             STIH407_DAC_STANDBY_ANA, 1, NULL, 0),
        SND_SOC_DAPM_DAC("DAC standby",  "dac_p", STIH407_AUDIO_DAC_CTRL,
                         STIH407_DAC_STANDBY, 1),
        SND_SOC_DAPM_OUTPUT("DAC Output"),
};

static const struct snd_soc_dapm_route stih407_sas_route[] = {
        {"DAC Output", NULL, "DAC standby ana"},
        {"DAC standby ana", NULL, "DAC standby"},
};


static int stih407_sas_dac_mute(struct snd_soc_dai *dai, int mute, int stream)
{
        struct snd_soc_component *component = dai->component;

        if (mute) {
                return snd_soc_component_update_bits(component, STIH407_AUDIO_DAC_CTRL,
                                            STIH407_DAC_SOFTMUTE_MASK,
                                            STIH407_DAC_SOFTMUTE_MASK);
        } else {
                return snd_soc_component_update_bits(component, STIH407_AUDIO_DAC_CTRL,
                                            STIH407_DAC_SOFTMUTE_MASK,
                                            0);
        }
}

/*
 * SPDIF
 */
static int sti_sas_spdif_set_fmt(struct snd_soc_dai *dai,
                                 unsigned int fmt)
{
        if ((fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) != SND_SOC_DAIFMT_CBC_CFC) {
                dev_err(dai->component->dev,
                        "%s: ERROR: Unsupported clocking mask 0x%x\n",
                        __func__, fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK);
                return -EINVAL;
        }

        return 0;
}

/*
 * sti_sas_spdif_trigger:
 * Trigger function is used to ensure that BiPhase Formater is disabled
 * before CPU dai is stopped.
 * This is mandatory to avoid that BPF is stalled
 */
static int sti_sas_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
                                 struct snd_soc_dai *dai)
{
        struct snd_soc_component *component = dai->component;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                return snd_soc_component_update_bits(component, STIH407_AUDIO_GLUE_CTRL,
                                            SPDIF_BIPHASE_ENABLE_MASK,
                                            SPDIF_BIPHASE_ENABLE_MASK);
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
                return snd_soc_component_update_bits(component, STIH407_AUDIO_GLUE_CTRL,
                                            SPDIF_BIPHASE_ENABLE_MASK,
                                            0);
        default:
                return -EINVAL;
        }
}

static bool sti_sas_volatile_register(struct device *dev, unsigned int reg)
{
        if (reg == STIH407_AUDIO_GLUE_CTRL)
                return true;

        return false;
}

/*
 * CODEC DAIS
 */

/*
 * sti_sas_set_sysclk:
 * get MCLK input frequency to check that MCLK-FS ratio is coherent
 */
static int sti_sas_set_sysclk(struct snd_soc_dai *dai, int clk_id,
                              unsigned int freq, int dir)
{
        struct snd_soc_component *component = dai->component;
        struct sti_sas_data *drvdata = dev_get_drvdata(component->dev);

        if (dir == SND_SOC_CLOCK_OUT)
                return 0;

        if (clk_id != 0)
                return -EINVAL;

        switch (dai->id) {
        case STI_SAS_DAI_SPDIF_OUT:
                drvdata->spdif.mclk = freq;
                break;

        case STI_SAS_DAI_ANALOG_OUT:
                drvdata->dac.mclk = freq;
                break;
        }

        return 0;
}

static int sti_sas_prepare(struct snd_pcm_substream *substream,
                           struct snd_soc_dai *dai)
{
        struct snd_soc_component *component = dai->component;
        struct sti_sas_data *drvdata = dev_get_drvdata(component->dev);
        struct snd_pcm_runtime *runtime = substream->runtime;

        switch (dai->id) {
        case STI_SAS_DAI_SPDIF_OUT:
                if ((drvdata->spdif.mclk / runtime->rate) != 128) {
                        dev_err(component->dev, "unexpected mclk-fs ratio\n");
                        return -EINVAL;
                }
                break;
        case STI_SAS_DAI_ANALOG_OUT:
                if ((drvdata->dac.mclk / runtime->rate) != 256) {
                        dev_err(component->dev, "unexpected mclk-fs ratio\n");
                        return -EINVAL;
                }
                break;
        }

        return 0;
}

static const struct snd_soc_dai_ops stih407_dac_ops = {
        .set_fmt = sti_sas_dac_set_fmt,
        .mute_stream = stih407_sas_dac_mute,
        .prepare = sti_sas_prepare,
        .set_sysclk = sti_sas_set_sysclk,
};

static const struct regmap_config stih407_sas_regmap = {
        .reg_bits = 32,
        .val_bits = 32,
        .fast_io = true,
        .max_register = STIH407_AUDIO_DAC_CTRL,
        .reg_defaults = stih407_sas_reg_defaults,
        .num_reg_defaults = ARRAY_SIZE(stih407_sas_reg_defaults),
        .volatile_reg = sti_sas_volatile_register,
        .cache_type = REGCACHE_MAPLE,
        .reg_read = sti_sas_read_reg,
        .reg_write = sti_sas_write_reg,
};

static const struct sti_sas_dev_data stih407_data = {
        .regmap = &stih407_sas_regmap,
        .dac_ops = &stih407_dac_ops,
};

static struct snd_soc_dai_driver sti_sas_dai[] = {
        {
                .name = "sas-dai-spdif-out",
                .id = STI_SAS_DAI_SPDIF_OUT,
                .playback = {
                        .stream_name = "spdif_p",
                        .channels_min = 2,
                        .channels_max = 2,
                        .rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
                                 SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_64000 |
                                 SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |
                                 SNDRV_PCM_RATE_192000,
                        .formats = SNDRV_PCM_FMTBIT_S16_LE |
                                   SNDRV_PCM_FMTBIT_S32_LE,
                },
                .ops = (struct snd_soc_dai_ops[]) {
                        {
                                .set_fmt = sti_sas_spdif_set_fmt,
                                .trigger = sti_sas_spdif_trigger,
                                .set_sysclk = sti_sas_set_sysclk,
                                .prepare = sti_sas_prepare,
                        }
                },
        },
        {
                .name = "sas-dai-dac",
                .id = STI_SAS_DAI_ANALOG_OUT,
                .playback = {
                        .stream_name = "dac_p",
                        .channels_min = 2,
                        .channels_max = 2,
                        .rates = SNDRV_PCM_RATE_8000_48000,
                        .formats = SNDRV_PCM_FMTBIT_S16_LE |
                                   SNDRV_PCM_FMTBIT_S32_LE,
                },
        },
};

#ifdef CONFIG_PM_SLEEP
static int sti_sas_resume(struct snd_soc_component *component)
{
        struct sti_sas_data *drvdata = dev_get_drvdata(component->dev);

        return sti_sas_init_sas_registers(component, drvdata);
}
#else
#define sti_sas_resume NULL
#endif

static int sti_sas_component_probe(struct snd_soc_component *component)
{
        struct sti_sas_data *drvdata = dev_get_drvdata(component->dev);

        return sti_sas_init_sas_registers(component, drvdata);
}

static const struct snd_soc_component_driver sti_sas_driver = {
        .probe                  = sti_sas_component_probe,
        .resume                 = sti_sas_resume,
        .idle_bias_on           = 1,
        .use_pmdown_time        = 1,
        .endianness             = 1,
        .dapm_widgets           = stih407_sas_dapm_widgets,
        .num_dapm_widgets       = ARRAY_SIZE(stih407_sas_dapm_widgets),
        .dapm_routes            = stih407_sas_route,
        .num_dapm_routes        = ARRAY_SIZE(stih407_sas_route),
};

static const struct of_device_id sti_sas_dev_match[] = {
        {
                .compatible = "st,stih407-sas-codec",
                .data = &stih407_data,
        },
        {},
};
MODULE_DEVICE_TABLE(of, sti_sas_dev_match);

static int sti_sas_driver_probe(struct platform_device *pdev)
{
        struct device_node *pnode = pdev->dev.of_node;
        struct sti_sas_data *drvdata;
        const struct of_device_id *of_id;

        /* Allocate device structure */
        drvdata = devm_kzalloc(&pdev->dev, sizeof(struct sti_sas_data),
                               GFP_KERNEL);
        if (!drvdata)
                return -ENOMEM;

        /* Populate data structure depending on compatibility */
        of_id = of_match_node(sti_sas_dev_match, pnode);
        if (!of_id->data) {
                dev_err(&pdev->dev, "data associated to device is missing\n");
                return -EINVAL;
        }

        drvdata->dev_data = (struct sti_sas_dev_data *)of_id->data;

        /* Initialise device structure */
        drvdata->dev = &pdev->dev;

        /* Request the DAC & SPDIF registers memory region */
        drvdata->dac.virt_regmap = devm_regmap_init(&pdev->dev, NULL, drvdata,
                                                    drvdata->dev_data->regmap);
        if (IS_ERR(drvdata->dac.virt_regmap)) {
                dev_err(&pdev->dev, "audio registers not enabled\n");
                return PTR_ERR(drvdata->dac.virt_regmap);
        }

        /* Request the syscon region */
        drvdata->dac.regmap =
                syscon_regmap_lookup_by_phandle(pnode, "st,syscfg");
        if (IS_ERR(drvdata->dac.regmap)) {
                dev_err(&pdev->dev, "syscon registers not available\n");
                return PTR_ERR(drvdata->dac.regmap);
        }
        drvdata->spdif.regmap = drvdata->dac.regmap;

        sti_sas_dai[STI_SAS_DAI_ANALOG_OUT].ops = drvdata->dev_data->dac_ops;

        /* Store context */
        dev_set_drvdata(&pdev->dev, drvdata);

        return devm_snd_soc_register_component(&pdev->dev, &sti_sas_driver,
                                        sti_sas_dai,
                                        ARRAY_SIZE(sti_sas_dai));
}

static struct platform_driver sti_sas_platform_driver = {
        .driver = {
                .name = "sti-sas-codec",
                .of_match_table = sti_sas_dev_match,
        },
        .probe = sti_sas_driver_probe,
};

module_platform_driver(sti_sas_platform_driver);

MODULE_DESCRIPTION("audio codec for STMicroelectronics sti platforms");
MODULE_AUTHOR("Arnaud.pouliquen@st.com");
MODULE_LICENSE("GPL v2");