root/sound/soc/fsl/fsl_aud2htx.c
// SPDX-License-Identifier: GPL-2.0+
// Copyright 2020 NXP

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/pm_qos.h>
#include <sound/core.h>
#include <sound/dmaengine_pcm.h>
#include <sound/pcm_params.h>
#include <linux/dma-mapping.h>

#include "fsl_aud2htx.h"
#include "imx-pcm.h"

static int fsl_aud2htx_trigger(struct snd_pcm_substream *substream, int cmd,
                               struct snd_soc_dai *dai)
{
        struct fsl_aud2htx *aud2htx = snd_soc_dai_get_drvdata(dai);

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL,
                                   AUD2HTX_CTRL_EN, AUD2HTX_CTRL_EN);
                regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
                                   AUD2HTX_CTRE_DE, AUD2HTX_CTRE_DE);
                break;
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
                                   AUD2HTX_CTRE_DE, 0);
                regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL,
                                   AUD2HTX_CTRL_EN, 0);
                break;
        default:
                return -EINVAL;
        }
        return 0;
}

static int fsl_aud2htx_dai_probe(struct snd_soc_dai *cpu_dai)
{
        struct fsl_aud2htx *aud2htx = dev_get_drvdata(cpu_dai->dev);

        /* DMA request when number of entries < WTMK_LOW */
        regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
                           AUD2HTX_CTRE_DT_MASK, 0);

        /* Disable interrupts*/
        regmap_update_bits(aud2htx->regmap, AUD2HTX_IRQ_MASK,
                           AUD2HTX_WM_HIGH_IRQ_MASK |
                           AUD2HTX_WM_LOW_IRQ_MASK |
                           AUD2HTX_OVF_MASK,
                           AUD2HTX_WM_HIGH_IRQ_MASK |
                           AUD2HTX_WM_LOW_IRQ_MASK |
                           AUD2HTX_OVF_MASK);

        /* Configure watermark */
        regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
                           AUD2HTX_CTRE_WL_MASK,
                           AUD2HTX_WTMK_LOW << AUD2HTX_CTRE_WL_SHIFT);
        regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
                           AUD2HTX_CTRE_WH_MASK,
                           AUD2HTX_WTMK_HIGH << AUD2HTX_CTRE_WH_SHIFT);

        snd_soc_dai_init_dma_data(cpu_dai, &aud2htx->dma_params_tx,
                                  &aud2htx->dma_params_rx);

        return 0;
}

static const struct snd_soc_dai_ops fsl_aud2htx_dai_ops = {
        .probe          = fsl_aud2htx_dai_probe,
        .trigger        = fsl_aud2htx_trigger,
};

static struct snd_soc_dai_driver fsl_aud2htx_dai = {
        .playback = {
                .stream_name = "CPU-Playback",
                .channels_min = 1,
                .channels_max = 8,
                .rates = SNDRV_PCM_RATE_32000 |
                         SNDRV_PCM_RATE_44100 |
                         SNDRV_PCM_RATE_48000 |
                         SNDRV_PCM_RATE_88200 |
                         SNDRV_PCM_RATE_96000 |
                         SNDRV_PCM_RATE_176400 |
                         SNDRV_PCM_RATE_192000,
                .formats = FSL_AUD2HTX_FORMATS,
        },
        .ops = &fsl_aud2htx_dai_ops,
};

static const struct snd_soc_component_driver fsl_aud2htx_component = {
        .name                   = "fsl-aud2htx",
        .legacy_dai_naming      = 1,
};

static const struct reg_default fsl_aud2htx_reg_defaults[] = {
        {AUD2HTX_CTRL,          0x00000000},
        {AUD2HTX_CTRL_EXT,      0x00000000},
        {AUD2HTX_WR,            0x00000000},
        {AUD2HTX_STATUS,        0x00000000},
        {AUD2HTX_IRQ_NOMASK,    0x00000000},
        {AUD2HTX_IRQ_MASKED,    0x00000000},
        {AUD2HTX_IRQ_MASK,      0x00000000},
};

static bool fsl_aud2htx_readable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case AUD2HTX_CTRL:
        case AUD2HTX_CTRL_EXT:
        case AUD2HTX_STATUS:
        case AUD2HTX_IRQ_NOMASK:
        case AUD2HTX_IRQ_MASKED:
        case AUD2HTX_IRQ_MASK:
                return true;
        default:
                return false;
        }
}

static bool fsl_aud2htx_writeable_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case AUD2HTX_CTRL:
        case AUD2HTX_CTRL_EXT:
        case AUD2HTX_WR:
        case AUD2HTX_IRQ_NOMASK:
        case AUD2HTX_IRQ_MASKED:
        case AUD2HTX_IRQ_MASK:
                return true;
        default:
                return false;
        }
}

static bool fsl_aud2htx_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case AUD2HTX_STATUS:
        case AUD2HTX_IRQ_NOMASK:
        case AUD2HTX_IRQ_MASKED:
                return true;
        default:
                return false;
        }
}

static const struct regmap_config fsl_aud2htx_regmap_config = {
        .reg_bits = 32,
        .reg_stride = 4,
        .val_bits = 32,

        .max_register = AUD2HTX_IRQ_MASK,
        .reg_defaults = fsl_aud2htx_reg_defaults,
        .num_reg_defaults = ARRAY_SIZE(fsl_aud2htx_reg_defaults),
        .readable_reg = fsl_aud2htx_readable_reg,
        .volatile_reg = fsl_aud2htx_volatile_reg,
        .writeable_reg = fsl_aud2htx_writeable_reg,
        .cache_type = REGCACHE_MAPLE,
};

static const struct of_device_id fsl_aud2htx_dt_ids[] = {
        { .compatible = "fsl,imx8mp-aud2htx",},
        {}
};
MODULE_DEVICE_TABLE(of, fsl_aud2htx_dt_ids);

static irqreturn_t fsl_aud2htx_isr(int irq, void *dev_id)
{
        return IRQ_HANDLED;
}

static int fsl_aud2htx_probe(struct platform_device *pdev)
{
        struct fsl_aud2htx *aud2htx;
        struct resource *res;
        void __iomem *regs;
        int ret, irq;

        aud2htx = devm_kzalloc(&pdev->dev, sizeof(*aud2htx), GFP_KERNEL);
        if (!aud2htx)
                return -ENOMEM;

        aud2htx->pdev = pdev;

        regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(regs))
                return PTR_ERR(regs);

        aud2htx->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
                                                &fsl_aud2htx_regmap_config);
        if (IS_ERR(aud2htx->regmap)) {
                dev_err(&pdev->dev, "failed to init regmap");
                return PTR_ERR(aud2htx->regmap);
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        ret = devm_request_irq(&pdev->dev, irq, fsl_aud2htx_isr, 0,
                               dev_name(&pdev->dev), aud2htx);
        if (ret) {
                dev_err(&pdev->dev, "failed to claim irq %u: %d\n", irq, ret);
                return ret;
        }

        aud2htx->bus_clk = devm_clk_get(&pdev->dev, "bus");
        if (IS_ERR(aud2htx->bus_clk)) {
                dev_err(&pdev->dev, "failed to get mem clock\n");
                return PTR_ERR(aud2htx->bus_clk);
        }

        aud2htx->dma_params_tx.chan_name = "tx";
        aud2htx->dma_params_tx.maxburst = AUD2HTX_MAXBURST;
        aud2htx->dma_params_tx.addr = res->start + AUD2HTX_WR;

        platform_set_drvdata(pdev, aud2htx);
        pm_runtime_enable(&pdev->dev);

        regcache_cache_only(aud2htx->regmap, true);

        /*
         * Register platform component before registering cpu dai for there
         * is not defer probe for platform component in snd_soc_add_pcm_runtime().
         */
        ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
        if (ret) {
                dev_err(&pdev->dev, "failed to pcm register\n");
                pm_runtime_disable(&pdev->dev);
                return ret;
        }

        ret = devm_snd_soc_register_component(&pdev->dev,
                                              &fsl_aud2htx_component,
                                              &fsl_aud2htx_dai, 1);
        if (ret) {
                dev_err(&pdev->dev, "failed to register ASoC DAI\n");
                pm_runtime_disable(&pdev->dev);
                return ret;
        }

        return ret;
}

static void fsl_aud2htx_remove(struct platform_device *pdev)
{
        pm_runtime_disable(&pdev->dev);
}

static int fsl_aud2htx_runtime_suspend(struct device *dev)
{
        struct fsl_aud2htx *aud2htx = dev_get_drvdata(dev);

        regcache_cache_only(aud2htx->regmap, true);
        clk_disable_unprepare(aud2htx->bus_clk);

        return 0;
}

static int fsl_aud2htx_runtime_resume(struct device *dev)
{
        struct fsl_aud2htx *aud2htx = dev_get_drvdata(dev);
        int ret;

        ret = clk_prepare_enable(aud2htx->bus_clk);
        if (ret)
                return ret;

        regcache_cache_only(aud2htx->regmap, false);
        regcache_mark_dirty(aud2htx->regmap);
        regcache_sync(aud2htx->regmap);

        return 0;
}

static const struct dev_pm_ops fsl_aud2htx_pm_ops = {
        RUNTIME_PM_OPS(fsl_aud2htx_runtime_suspend, fsl_aud2htx_runtime_resume,
                       NULL)
        SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
};

static struct platform_driver fsl_aud2htx_driver = {
        .probe = fsl_aud2htx_probe,
        .remove = fsl_aud2htx_remove,
        .driver = {
                .name = "fsl-aud2htx",
                .pm = pm_ptr(&fsl_aud2htx_pm_ops),
                .of_match_table = fsl_aud2htx_dt_ids,
        },
};
module_platform_driver(fsl_aud2htx_driver);

MODULE_AUTHOR("Shengjiu Wang <Shengjiu.Wang@nxp.com>");
MODULE_DESCRIPTION("NXP AUD2HTX driver");
MODULE_LICENSE("GPL v2");