root/sound/soc/starfive/jh7110_tdm.c
// SPDX-License-Identifier: GPL-2.0
/*
 * jh7110_tdm.c -- StarFive JH7110 TDM driver
 *
 * Copyright (C) 2023 StarFive Technology Co., Ltd.
 *
 * Author: Walker Chen <walker.chen@starfivetech.com>
 */

#include <linux/clk.h>
#include <linux/device.h>
#include <linux/dmaengine.h>
#include <linux/minmax.h>
#include <linux/module.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/types.h>
#include <sound/dmaengine_pcm.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/soc-dai.h>

#define TDM_PCMGBCR                     0x00
        #define PCMGBCR_ENABLE          BIT(0)
        #define CLKPOL_BIT              5
        #define ELM_BIT                 3
        #define SYNCM_BIT               2
        #define MS_BIT                  1
#define TDM_PCMTXCR                     0x04
        #define PCMTXCR_TXEN            BIT(0)
        #define IFL_BIT                 11
        #define WL_BIT                  8
        #define SSCALE_BIT              4
        #define SL_BIT                  2
        #define LRJ_BIT                 1
#define TDM_PCMRXCR                     0x08
        #define PCMRXCR_RXEN            BIT(0)
#define TDM_PCMDIV                      0x0c

#define JH7110_TDM_FIFO                 0x170c0000
#define JH7110_TDM_FIFO_DEPTH           32

enum TDM_MASTER_SLAVE_MODE {
        TDM_AS_MASTER = 0,
        TDM_AS_SLAVE,
};

enum TDM_CLKPOL {
        /* tx raising and rx falling */
        TDM_TX_RASING_RX_FALLING = 0,
        /* tx falling and rx raising */
        TDM_TX_FALLING_RX_RASING,
};

enum TDM_ELM {
        /* only work while SYNCM=0 */
        TDM_ELM_LATE = 0,
        TDM_ELM_EARLY,
};

enum TDM_SYNCM {
        /* short frame sync */
        TDM_SYNCM_SHORT = 0,
        /* long frame sync */
        TDM_SYNCM_LONG,
};

enum TDM_IFL {
        /* FIFO to send or received : half-1/2, Quarter-1/4 */
        TDM_FIFO_HALF = 0,
        TDM_FIFO_QUARTER,
};

enum TDM_WL {
        /* send or received word length */
        TDM_8BIT_WORD_LEN = 0,
        TDM_16BIT_WORD_LEN,
        TDM_20BIT_WORD_LEN,
        TDM_24BIT_WORD_LEN,
        TDM_32BIT_WORD_LEN,
};

enum TDM_SL {
        /* send or received slot length */
        TDM_8BIT_SLOT_LEN = 0,
        TDM_16BIT_SLOT_LEN,
        TDM_32BIT_SLOT_LEN,
};

enum TDM_LRJ {
        /* left-justify or right-justify */
        TDM_RIGHT_JUSTIFY = 0,
        TDM_LEFT_JUSTIFT,
};

struct tdm_chan_cfg {
        enum TDM_IFL ifl;
        enum TDM_WL  wl;
        unsigned char sscale;
        enum TDM_SL  sl;
        enum TDM_LRJ lrj;
        unsigned char enable;
};

struct jh7110_tdm_dev {
        void __iomem *tdm_base;
        struct device *dev;
        struct clk_bulk_data clks[6];
        struct reset_control *resets;

        enum TDM_CLKPOL clkpolity;
        enum TDM_ELM    elm;
        enum TDM_SYNCM  syncm;
        enum TDM_MASTER_SLAVE_MODE ms_mode;

        struct tdm_chan_cfg tx;
        struct tdm_chan_cfg rx;

        u16 syncdiv;
        u32 samplerate;
        u32 pcmclk;

        /* data related to DMA transfers b/w tdm and DMAC */
        struct snd_dmaengine_dai_dma_data play_dma_data;
        struct snd_dmaengine_dai_dma_data capture_dma_data;
        u32 saved_pcmgbcr;
        u32 saved_pcmtxcr;
        u32 saved_pcmrxcr;
        u32 saved_pcmdiv;
};

static inline u32 jh7110_tdm_readl(struct jh7110_tdm_dev *tdm, u16 reg)
{
        return readl_relaxed(tdm->tdm_base + reg);
}

static inline void jh7110_tdm_writel(struct jh7110_tdm_dev *tdm, u16 reg, u32 val)
{
        writel_relaxed(val, tdm->tdm_base + reg);
}

static void jh7110_tdm_save_context(struct jh7110_tdm_dev *tdm,
                                    struct snd_pcm_substream *substream)
{
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                tdm->saved_pcmtxcr = jh7110_tdm_readl(tdm, TDM_PCMTXCR);
        else
                tdm->saved_pcmrxcr = jh7110_tdm_readl(tdm, TDM_PCMRXCR);
}

static void jh7110_tdm_start(struct jh7110_tdm_dev *tdm,
                             struct snd_pcm_substream *substream)
{
        u32 data;

        data = jh7110_tdm_readl(tdm, TDM_PCMGBCR);
        jh7110_tdm_writel(tdm, TDM_PCMGBCR, data | PCMGBCR_ENABLE);

        /* restore context */
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                jh7110_tdm_writel(tdm, TDM_PCMTXCR, tdm->saved_pcmtxcr | PCMTXCR_TXEN);
        else
                jh7110_tdm_writel(tdm, TDM_PCMRXCR, tdm->saved_pcmrxcr | PCMRXCR_RXEN);
}

static void jh7110_tdm_stop(struct jh7110_tdm_dev *tdm,
                            struct snd_pcm_substream *substream)
{
        unsigned int val;

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                val = jh7110_tdm_readl(tdm, TDM_PCMTXCR);
                val &= ~PCMTXCR_TXEN;
                jh7110_tdm_writel(tdm, TDM_PCMTXCR, val);
        } else {
                val = jh7110_tdm_readl(tdm, TDM_PCMRXCR);
                val &= ~PCMRXCR_RXEN;
                jh7110_tdm_writel(tdm, TDM_PCMRXCR, val);
        }
}

static int jh7110_tdm_syncdiv(struct jh7110_tdm_dev *tdm)
{
        u32 sl, sscale, syncdiv;

        sl = max(tdm->rx.sl, tdm->tx.sl);
        sscale = max(tdm->rx.sscale, tdm->tx.sscale);
        syncdiv = tdm->pcmclk / tdm->samplerate - 1;

        if ((syncdiv + 1) < (sl * sscale)) {
                dev_err(tdm->dev, "Failed to set syncdiv!\n");
                return -EINVAL;
        }

        if (tdm->syncm == TDM_SYNCM_LONG &&
            (tdm->rx.sscale <= 1 || tdm->tx.sscale <= 1) &&
            ((syncdiv + 1) <= sl)) {
                dev_err(tdm->dev, "Wrong syncdiv! It must be (syncdiv+1) > max[tx.sl, rx.sl]\n");
                return -EINVAL;
        }

        jh7110_tdm_writel(tdm, TDM_PCMDIV, syncdiv);
        return 0;
}

static int jh7110_tdm_config(struct jh7110_tdm_dev *tdm,
                             struct snd_pcm_substream *substream)
{
        u32 datarx, datatx;
        int ret;

        ret = jh7110_tdm_syncdiv(tdm);
        if (ret)
                return ret;

        datarx = (tdm->rx.ifl << IFL_BIT) |
                  (tdm->rx.wl << WL_BIT) |
                  (tdm->rx.sscale << SSCALE_BIT) |
                  (tdm->rx.sl << SL_BIT) |
                  (tdm->rx.lrj << LRJ_BIT);

        datatx = (tdm->tx.ifl << IFL_BIT) |
                  (tdm->tx.wl << WL_BIT) |
                  (tdm->tx.sscale << SSCALE_BIT) |
                  (tdm->tx.sl << SL_BIT) |
                  (tdm->tx.lrj << LRJ_BIT);

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                jh7110_tdm_writel(tdm, TDM_PCMTXCR, datatx);
        else
                jh7110_tdm_writel(tdm, TDM_PCMRXCR, datarx);

        return 0;
}

static void jh7110_tdm_clk_disable(struct jh7110_tdm_dev *tdm)
{
        clk_bulk_disable_unprepare(ARRAY_SIZE(tdm->clks), tdm->clks);
}

static int jh7110_tdm_clk_enable(struct jh7110_tdm_dev *tdm)
{
        int ret;

        ret = clk_bulk_prepare_enable(ARRAY_SIZE(tdm->clks), tdm->clks);
        if (ret) {
                dev_err(tdm->dev, "Failed to enable tdm clocks\n");
                return ret;
        }

        ret = reset_control_deassert(tdm->resets);
        if (ret) {
                dev_err(tdm->dev, "Failed to deassert tdm resets\n");
                goto dis_tdm_clk;
        }

        /* select tdm_ext clock as the clock source for tdm */
        ret = clk_set_parent(tdm->clks[5].clk, tdm->clks[4].clk);
        if (ret) {
                dev_err(tdm->dev, "Can't set extern clock source for clk_tdm\n");
                goto dis_tdm_clk;
        }

        return 0;

dis_tdm_clk:
        clk_bulk_disable_unprepare(ARRAY_SIZE(tdm->clks), tdm->clks);

        return ret;
}

static int jh7110_tdm_runtime_suspend(struct device *dev)
{
        struct jh7110_tdm_dev *tdm = dev_get_drvdata(dev);

        jh7110_tdm_clk_disable(tdm);
        return 0;
}

static int jh7110_tdm_runtime_resume(struct device *dev)
{
        struct jh7110_tdm_dev *tdm = dev_get_drvdata(dev);

        return jh7110_tdm_clk_enable(tdm);
}

static int jh7110_tdm_system_suspend(struct device *dev)
{
        struct jh7110_tdm_dev *tdm = dev_get_drvdata(dev);

        /* save context */
        tdm->saved_pcmgbcr = jh7110_tdm_readl(tdm, TDM_PCMGBCR);
        tdm->saved_pcmdiv = jh7110_tdm_readl(tdm, TDM_PCMDIV);

        return pm_runtime_force_suspend(dev);
}

static int jh7110_tdm_system_resume(struct device *dev)
{
        struct jh7110_tdm_dev *tdm = dev_get_drvdata(dev);

        /* restore context */
        jh7110_tdm_writel(tdm, TDM_PCMGBCR, tdm->saved_pcmgbcr);
        jh7110_tdm_writel(tdm, TDM_PCMDIV, tdm->saved_pcmdiv);

        return pm_runtime_force_resume(dev);
}

static const struct snd_soc_component_driver jh7110_tdm_component = {
        .name = "jh7110-tdm",
};

static int jh7110_tdm_startup(struct snd_pcm_substream *substream,
                              struct snd_soc_dai *cpu_dai)
{
        struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
        struct snd_soc_dai_link *dai_link = rtd->dai_link;

        dai_link->trigger_stop = SND_SOC_TRIGGER_ORDER_LDC;

        return 0;
}

static int jh7110_tdm_hw_params(struct snd_pcm_substream *substream,
                                struct snd_pcm_hw_params *params,
                                struct snd_soc_dai *dai)
{
        struct jh7110_tdm_dev *tdm = snd_soc_dai_get_drvdata(dai);
        int chan_wl, chan_sl, chan_nr;
        unsigned int data_width;
        unsigned int dma_bus_width;
        struct snd_dmaengine_dai_dma_data *dma_data = NULL;
        int ret;

        data_width = params_width(params);

        tdm->samplerate = params_rate(params);
        tdm->pcmclk = params_channels(params) * tdm->samplerate * data_width;

        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S16_LE:
                chan_wl = TDM_16BIT_WORD_LEN;
                chan_sl = TDM_16BIT_SLOT_LEN;
                dma_bus_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
                break;

        case SNDRV_PCM_FORMAT_S32_LE:
                chan_wl = TDM_32BIT_WORD_LEN;
                chan_sl = TDM_32BIT_SLOT_LEN;
                dma_bus_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
                break;

        default:
                dev_err(tdm->dev, "tdm: unsupported PCM fmt");
                return -EINVAL;
        }

        chan_nr = params_channels(params);
        switch (chan_nr) {
        case 1:
        case 2:
        case 4:
        case 6:
        case 8:
                break;
        default:
                dev_err(tdm->dev, "channel not supported\n");
                return -EINVAL;
        }

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                tdm->tx.wl = chan_wl;
                tdm->tx.sl = chan_sl;
                tdm->tx.sscale = chan_nr;
                tdm->play_dma_data.addr_width = dma_bus_width;
                dma_data = &tdm->play_dma_data;
        } else {
                tdm->rx.wl = chan_wl;
                tdm->rx.sl = chan_sl;
                tdm->rx.sscale = chan_nr;
                tdm->capture_dma_data.addr_width = dma_bus_width;
                dma_data = &tdm->capture_dma_data;
        }

        snd_soc_dai_set_dma_data(dai, substream, dma_data);

        ret = jh7110_tdm_config(tdm, substream);
        if (ret)
                return ret;

        jh7110_tdm_save_context(tdm, substream);
        return 0;
}

static int jh7110_tdm_trigger(struct snd_pcm_substream *substream,
                              int cmd, struct snd_soc_dai *dai)
{
        struct jh7110_tdm_dev *tdm = snd_soc_dai_get_drvdata(dai);
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                jh7110_tdm_start(tdm, substream);
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                jh7110_tdm_stop(tdm, substream);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int jh7110_tdm_set_dai_fmt(struct snd_soc_dai *cpu_dai,
                                  unsigned int fmt)
{
        struct jh7110_tdm_dev *tdm = snd_soc_dai_get_drvdata(cpu_dai);
        unsigned int gbcr;

        /* set master/slave audio interface */
        switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
        case SND_SOC_DAIFMT_BP_FP:
                /* cpu is master */
                tdm->ms_mode = TDM_AS_MASTER;
                break;
        case SND_SOC_DAIFMT_BC_FC:
                /* codec is master */
                tdm->ms_mode = TDM_AS_SLAVE;
                break;
        case SND_SOC_DAIFMT_BC_FP:
        case SND_SOC_DAIFMT_BP_FC:
                return -EINVAL;
        default:
                dev_dbg(tdm->dev, "dwc : Invalid clock provider format\n");
                return -EINVAL;
        }

        gbcr = (tdm->clkpolity << CLKPOL_BIT) |
                (tdm->elm << ELM_BIT) |
                (tdm->syncm << SYNCM_BIT) |
                (tdm->ms_mode << MS_BIT);
        jh7110_tdm_writel(tdm, TDM_PCMGBCR, gbcr);

        return 0;
}

static int jh7110_tdm_dai_probe(struct snd_soc_dai *dai)
{
        struct jh7110_tdm_dev *tdm = snd_soc_dai_get_drvdata(dai);

        snd_soc_dai_init_dma_data(dai, &tdm->play_dma_data, &tdm->capture_dma_data);
        snd_soc_dai_set_drvdata(dai, tdm);
        return 0;
}

static const struct snd_soc_dai_ops jh7110_tdm_dai_ops = {
        .probe          = jh7110_tdm_dai_probe,
        .startup        = jh7110_tdm_startup,
        .hw_params      = jh7110_tdm_hw_params,
        .trigger        = jh7110_tdm_trigger,
        .set_fmt        = jh7110_tdm_set_dai_fmt,
};

#define JH7110_TDM_RATES        SNDRV_PCM_RATE_8000_48000

#define JH7110_TDM_FORMATS      (SNDRV_PCM_FMTBIT_S16_LE | \
                                 SNDRV_PCM_FMTBIT_S32_LE)

static struct snd_soc_dai_driver jh7110_tdm_dai = {
        .name = "sf_tdm",
        .id = 0,
        .playback = {
                .stream_name    = "Playback",
                .channels_min   = 1,
                .channels_max   = 8,
                .rates          = JH7110_TDM_RATES,
                .formats        = JH7110_TDM_FORMATS,
        },
        .capture = {
                .stream_name    = "Capture",
                .channels_min   = 1,
                .channels_max   = 8,
                .rates          = JH7110_TDM_RATES,
                .formats        = JH7110_TDM_FORMATS,
        },
        .ops = &jh7110_tdm_dai_ops,
        .symmetric_rate = 1,
};

static const struct snd_pcm_hardware jh7110_pcm_hardware = {
        .info                   = (SNDRV_PCM_INFO_MMAP          |
                                   SNDRV_PCM_INFO_MMAP_VALID    |
                                   SNDRV_PCM_INFO_PAUSE         |
                                   SNDRV_PCM_INFO_RESUME        |
                                   SNDRV_PCM_INFO_INTERLEAVED   |
                                   SNDRV_PCM_INFO_BLOCK_TRANSFER),
        .buffer_bytes_max       = 192512,
        .period_bytes_min       = 4096,
        .period_bytes_max       = 32768,
        .periods_min            = 1,
        .periods_max            = 48,
        .fifo_size              = 16,
};

static const struct snd_dmaengine_pcm_config jh7110_dmaengine_pcm_config = {
        .pcm_hardware = &jh7110_pcm_hardware,
        .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
        .prealloc_buffer_size = 192512,
};

static void jh7110_tdm_init_params(struct jh7110_tdm_dev *tdm)
{
        tdm->clkpolity = TDM_TX_RASING_RX_FALLING;
        tdm->elm = TDM_ELM_LATE;
        tdm->syncm = TDM_SYNCM_SHORT;

        tdm->rx.ifl = TDM_FIFO_HALF;
        tdm->tx.ifl = TDM_FIFO_HALF;
        tdm->rx.wl = TDM_16BIT_WORD_LEN;
        tdm->tx.wl = TDM_16BIT_WORD_LEN;
        tdm->rx.sscale = 2;
        tdm->tx.sscale = 2;
        tdm->rx.lrj = TDM_LEFT_JUSTIFT;
        tdm->tx.lrj = TDM_LEFT_JUSTIFT;

        tdm->play_dma_data.addr = JH7110_TDM_FIFO;
        tdm->play_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
        tdm->play_dma_data.fifo_size = JH7110_TDM_FIFO_DEPTH / 2;
        tdm->play_dma_data.maxburst = 16;

        tdm->capture_dma_data.addr = JH7110_TDM_FIFO;
        tdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
        tdm->capture_dma_data.fifo_size = JH7110_TDM_FIFO_DEPTH / 2;
        tdm->capture_dma_data.maxburst = 8;
}

static int jh7110_tdm_clk_reset_get(struct platform_device *pdev,
                                    struct jh7110_tdm_dev *tdm)
{
        int ret;

        tdm->clks[0].id = "mclk_inner";
        tdm->clks[1].id = "tdm_ahb";
        tdm->clks[2].id = "tdm_apb";
        tdm->clks[3].id = "tdm_internal";
        tdm->clks[4].id = "tdm_ext";
        tdm->clks[5].id = "tdm";

        ret = devm_clk_bulk_get(&pdev->dev, ARRAY_SIZE(tdm->clks), tdm->clks);
        if (ret) {
                dev_err(&pdev->dev, "Failed to get tdm clocks\n");
                return ret;
        }

        tdm->resets = devm_reset_control_array_get_exclusive(&pdev->dev);
        if (IS_ERR(tdm->resets)) {
                dev_err(&pdev->dev, "Failed to get tdm resets\n");
                return PTR_ERR(tdm->resets);
        }

        return 0;
}

static int jh7110_tdm_probe(struct platform_device *pdev)
{
        struct jh7110_tdm_dev *tdm;
        int ret;

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

        tdm->tdm_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(tdm->tdm_base))
                return PTR_ERR(tdm->tdm_base);

        tdm->dev = &pdev->dev;

        ret = jh7110_tdm_clk_reset_get(pdev, tdm);
        if (ret) {
                dev_err(&pdev->dev, "Failed to enable audio-tdm clock\n");
                return ret;
        }

        jh7110_tdm_init_params(tdm);

        dev_set_drvdata(&pdev->dev, tdm);
        ret = devm_snd_soc_register_component(&pdev->dev, &jh7110_tdm_component,
                                              &jh7110_tdm_dai, 1);
        if (ret) {
                dev_err(&pdev->dev, "Failed to register dai\n");
                return ret;
        }

        ret = devm_snd_dmaengine_pcm_register(&pdev->dev,
                                              &jh7110_dmaengine_pcm_config,
                                              SND_DMAENGINE_PCM_FLAG_COMPAT);
        if (ret) {
                dev_err(&pdev->dev, "Could not register pcm: %d\n", ret);
                return ret;
        }

        pm_runtime_enable(&pdev->dev);
        if (!pm_runtime_enabled(&pdev->dev)) {
                ret = jh7110_tdm_runtime_resume(&pdev->dev);
                if (ret)
                        goto err_pm_disable;
        }

        return 0;

err_pm_disable:
        pm_runtime_disable(&pdev->dev);

        return ret;
}

static void jh7110_tdm_dev_remove(struct platform_device *pdev)
{
        pm_runtime_disable(&pdev->dev);
}

static const struct of_device_id jh7110_tdm_of_match[] = {
        { .compatible = "starfive,jh7110-tdm", },
        {}
};

MODULE_DEVICE_TABLE(of, jh7110_tdm_of_match);

static const struct dev_pm_ops jh7110_tdm_pm_ops = {
        RUNTIME_PM_OPS(jh7110_tdm_runtime_suspend,
                       jh7110_tdm_runtime_resume, NULL)
        SYSTEM_SLEEP_PM_OPS(jh7110_tdm_system_suspend,
                            jh7110_tdm_system_resume)
};

static struct platform_driver jh7110_tdm_driver = {
        .driver = {
                .name = "jh7110-tdm",
                .of_match_table = jh7110_tdm_of_match,
                .pm = pm_ptr(&jh7110_tdm_pm_ops),
        },
        .probe = jh7110_tdm_probe,
        .remove = jh7110_tdm_dev_remove,
};
module_platform_driver(jh7110_tdm_driver);

MODULE_DESCRIPTION("StarFive JH7110 TDM ASoC Driver");
MODULE_AUTHOR("Walker Chen <walker.chen@starfivetech.com>");
MODULE_LICENSE("GPL");