root/sound/soc/rockchip/rockchip_pdm.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Rockchip PDM ALSA SoC Digital Audio Interface(DAI)  driver
 *
 * Copyright (C) 2017 Fuzhou Rockchip Electronics Co., Ltd
 */

#include <linux/module.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/rational.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <sound/dmaengine_pcm.h>
#include <sound/pcm_params.h>

#include "rockchip_pdm.h"

#define PDM_DMA_BURST_SIZE      (8) /* size * width: 8*4 = 32 bytes */
#define PDM_SIGNOFF_CLK_RATE    (100000000)
#define PDM_PATH_MAX            (4)

enum rk_pdm_version {
        RK_PDM_RK3229,
        RK_PDM_RK3308,
        RK_PDM_RV1126,
};

struct rk_pdm_dev {
        struct device *dev;
        struct clk *clk;
        struct clk *hclk;
        struct regmap *regmap;
        struct snd_dmaengine_dai_dma_data capture_dma_data;
        struct reset_control *reset;
        enum rk_pdm_version version;
};

struct rk_pdm_clkref {
        unsigned int sr;
        unsigned int clk;
        unsigned int clk_out;
};

struct rk_pdm_ds_ratio {
        unsigned int ratio;
        unsigned int sr;
};

static struct rk_pdm_clkref clkref[] = {
        { 8000, 40960000, 2048000 },
        { 11025, 56448000, 2822400 },
        { 12000, 61440000, 3072000 },
        { 8000, 98304000, 2048000 },
        { 12000, 98304000, 3072000 },
};

static struct rk_pdm_ds_ratio ds_ratio[] = {
        { 0, 192000 },
        { 0, 176400 },
        { 0, 128000 },
        { 1, 96000 },
        { 1, 88200 },
        { 1, 64000 },
        { 2, 48000 },
        { 2, 44100 },
        { 2, 32000 },
        { 3, 24000 },
        { 3, 22050 },
        { 3, 16000 },
        { 4, 12000 },
        { 4, 11025 },
        { 4, 8000 },
};

static unsigned int get_pdm_clk(struct rk_pdm_dev *pdm, unsigned int sr,
                                unsigned int *clk_src, unsigned int *clk_out)
{
        unsigned int i, count, clk, div, rate;

        clk = 0;
        if (!sr)
                return clk;

        count = ARRAY_SIZE(clkref);
        for (i = 0; i < count; i++) {
                if (sr % clkref[i].sr)
                        continue;
                div = sr / clkref[i].sr;
                if ((div & (div - 1)) == 0) {
                        *clk_out = clkref[i].clk_out;
                        rate = clk_round_rate(pdm->clk, clkref[i].clk);
                        if (rate != clkref[i].clk)
                                continue;
                        clk = clkref[i].clk;
                        *clk_src = clkref[i].clk;
                        break;
                }
        }

        if (!clk) {
                clk = clk_round_rate(pdm->clk, PDM_SIGNOFF_CLK_RATE);
                *clk_src = clk;
        }
        return clk;
}

static unsigned int get_pdm_ds_ratio(unsigned int sr)
{
        unsigned int i, count, ratio;

        ratio = 0;
        if (!sr)
                return ratio;

        count = ARRAY_SIZE(ds_ratio);
        for (i = 0; i < count; i++) {
                if (sr == ds_ratio[i].sr)
                        ratio = ds_ratio[i].ratio;
        }
        return ratio;
}

static unsigned int get_pdm_cic_ratio(unsigned int clk)
{
        switch (clk) {
        case 4096000:
        case 5644800:
        case 6144000:
                return 0;
        case 2048000:
        case 2822400:
        case 3072000:
                return 1;
        case 1024000:
        case 1411200:
        case 1536000:
                return 2;
        default:
                return 1;
        }
}

static unsigned int samplerate_to_bit(unsigned int samplerate)
{
        switch (samplerate) {
        case 8000:
        case 11025:
        case 12000:
                return 0;
        case 16000:
        case 22050:
        case 24000:
                return 1;
        case 32000:
                return 2;
        case 44100:
        case 48000:
                return 3;
        case 64000:
        case 88200:
        case 96000:
                return 4;
        case 128000:
        case 176400:
        case 192000:
                return 5;
        default:
                return 1;
        }
}

static inline struct rk_pdm_dev *to_info(struct snd_soc_dai *dai)
{
        return snd_soc_dai_get_drvdata(dai);
}

static void rockchip_pdm_rxctrl(struct rk_pdm_dev *pdm, int on)
{
        if (on) {
                regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
                                   PDM_DMA_RD_MSK, PDM_DMA_RD_EN);
                regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
                                   PDM_RX_MASK, PDM_RX_START);
        } else {
                regmap_update_bits(pdm->regmap, PDM_DMA_CTRL,
                                   PDM_DMA_RD_MSK, PDM_DMA_RD_DIS);
                regmap_update_bits(pdm->regmap, PDM_SYSCONFIG,
                                   PDM_RX_MASK | PDM_RX_CLR_MASK,
                                   PDM_RX_STOP | PDM_RX_CLR_WR);
        }
}

static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream,
                                  struct snd_pcm_hw_params *params,
                                  struct snd_soc_dai *dai)
{
        struct rk_pdm_dev *pdm = to_info(dai);
        unsigned int val = 0;
        unsigned int clk_rate, clk_div, samplerate;
        unsigned int clk_src, clk_out = 0;
        unsigned long m, n;
        bool change;
        int ret;

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                return 0;

        samplerate = params_rate(params);
        clk_rate = get_pdm_clk(pdm, samplerate, &clk_src, &clk_out);
        if (!clk_rate)
                return -EINVAL;

        ret = clk_set_rate(pdm->clk, clk_src);
        if (ret)
                return -EINVAL;

        if (pdm->version == RK_PDM_RK3308 ||
            pdm->version == RK_PDM_RV1126) {
                rational_best_approximation(clk_out, clk_src,
                                            GENMASK(16 - 1, 0),
                                            GENMASK(16 - 1, 0),
                                            &m, &n);

                val = (m << PDM_FD_NUMERATOR_SFT) |
                        (n << PDM_FD_DENOMINATOR_SFT);
                regmap_update_bits_check(pdm->regmap, PDM_CTRL1,
                                         PDM_FD_NUMERATOR_MSK |
                                         PDM_FD_DENOMINATOR_MSK,
                                         val, &change);
                if (change) {
                        reset_control_assert(pdm->reset);
                        reset_control_deassert(pdm->reset);
                        rockchip_pdm_rxctrl(pdm, 0);
                }
                clk_div = n / m;
                if (clk_div >= 40)
                        val = PDM_CLK_FD_RATIO_40;
                else if (clk_div <= 35)
                        val = PDM_CLK_FD_RATIO_35;
                else
                        return -EINVAL;
                regmap_update_bits(pdm->regmap, PDM_CLK_CTRL,
                                   PDM_CLK_FD_RATIO_MSK,
                                   val);
        }

        if (pdm->version == RK_PDM_RV1126) {
                val = get_pdm_cic_ratio(clk_out);
                regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CIC_RATIO_MSK, val);
                val = samplerate_to_bit(samplerate);
                regmap_update_bits(pdm->regmap, PDM_CTRL0,
                                   PDM_SAMPLERATE_MSK, PDM_SAMPLERATE(val));
        } else {
                val = get_pdm_ds_ratio(samplerate);
                regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);
        }

        regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
                           PDM_HPF_CF_MSK, PDM_HPF_60HZ);
        regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
                           PDM_HPF_LE | PDM_HPF_RE, PDM_HPF_LE | PDM_HPF_RE);
        regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CLK_EN, PDM_CLK_EN);
        if (pdm->version != RK_PDM_RK3229)
                regmap_update_bits(pdm->regmap, PDM_CTRL0,
                                   PDM_MODE_MSK, PDM_MODE_LJ);

        val = 0;
        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S8:
                val |= PDM_VDW(8);
                break;
        case SNDRV_PCM_FORMAT_S16_LE:
                val |= PDM_VDW(16);
                break;
        case SNDRV_PCM_FORMAT_S20_3LE:
                val |= PDM_VDW(20);
                break;
        case SNDRV_PCM_FORMAT_S24_LE:
                val |= PDM_VDW(24);
                break;
        case SNDRV_PCM_FORMAT_S32_LE:
                val |= PDM_VDW(32);
                break;
        default:
                return -EINVAL;
        }

        switch (params_channels(params)) {
        case 8:
                val |= PDM_PATH3_EN;
                fallthrough;
        case 6:
                val |= PDM_PATH2_EN;
                fallthrough;
        case 4:
                val |= PDM_PATH1_EN;
                fallthrough;
        case 2:
                val |= PDM_PATH0_EN;
                break;
        default:
                dev_err(pdm->dev, "invalid channel: %d\n",
                        params_channels(params));
                return -EINVAL;
        }

        regmap_update_bits(pdm->regmap, PDM_CTRL0,
                           PDM_PATH_MSK | PDM_VDW_MSK,
                           val);
        /* all channels share the single FIFO */
        regmap_update_bits(pdm->regmap, PDM_DMA_CTRL, PDM_DMA_RDL_MSK,
                           PDM_DMA_RDL(8 * params_channels(params)));

        return 0;
}

static int rockchip_pdm_set_fmt(struct snd_soc_dai *cpu_dai,
                                unsigned int fmt)
{
        struct rk_pdm_dev *pdm = to_info(cpu_dai);
        unsigned int mask = 0, val = 0;

        mask = PDM_CKP_MSK;
        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
        case SND_SOC_DAIFMT_NB_NF:
                val = PDM_CKP_NORMAL;
                break;
        case SND_SOC_DAIFMT_IB_NF:
                val = PDM_CKP_INVERTED;
                break;
        default:
                return -EINVAL;
        }

        pm_runtime_get_sync(cpu_dai->dev);
        regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, mask, val);
        pm_runtime_put(cpu_dai->dev);

        return 0;
}

static int rockchip_pdm_trigger(struct snd_pcm_substream *substream, int cmd,
                                struct snd_soc_dai *dai)
{
        struct rk_pdm_dev *pdm = to_info(dai);
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                        rockchip_pdm_rxctrl(pdm, 1);
                break;
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                        rockchip_pdm_rxctrl(pdm, 0);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int rockchip_pdm_dai_probe(struct snd_soc_dai *dai)
{
        struct rk_pdm_dev *pdm = to_info(dai);

        snd_soc_dai_dma_data_set_capture(dai, &pdm->capture_dma_data);

        return 0;
}

static const struct snd_soc_dai_ops rockchip_pdm_dai_ops = {
        .probe = rockchip_pdm_dai_probe,
        .set_fmt = rockchip_pdm_set_fmt,
        .trigger = rockchip_pdm_trigger,
        .hw_params = rockchip_pdm_hw_params,
};

#define ROCKCHIP_PDM_RATES SNDRV_PCM_RATE_8000_192000
#define ROCKCHIP_PDM_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
                              SNDRV_PCM_FMTBIT_S20_3LE | \
                              SNDRV_PCM_FMTBIT_S24_LE | \
                              SNDRV_PCM_FMTBIT_S32_LE)

static struct snd_soc_dai_driver rockchip_pdm_dai = {
        .capture = {
                .stream_name = "Capture",
                .channels_min = 2,
                .channels_max = 8,
                .rates = ROCKCHIP_PDM_RATES,
                .formats = ROCKCHIP_PDM_FORMATS,
        },
        .ops = &rockchip_pdm_dai_ops,
        .symmetric_rate = 1,
};

static const struct snd_soc_component_driver rockchip_pdm_component = {
        .name = "rockchip-pdm",
        .legacy_dai_naming = 1,
};

static int rockchip_pdm_runtime_suspend(struct device *dev)
{
        struct rk_pdm_dev *pdm = dev_get_drvdata(dev);

        clk_disable_unprepare(pdm->clk);
        clk_disable_unprepare(pdm->hclk);

        return 0;
}

static int rockchip_pdm_runtime_resume(struct device *dev)
{
        struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
        int ret;

        ret = clk_prepare_enable(pdm->clk);
        if (ret) {
                dev_err(pdm->dev, "clock enable failed %d\n", ret);
                return ret;
        }

        ret = clk_prepare_enable(pdm->hclk);
        if (ret) {
                clk_disable_unprepare(pdm->clk);
                dev_err(pdm->dev, "hclock enable failed %d\n", ret);
                return ret;
        }

        return 0;
}

static bool rockchip_pdm_wr_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case PDM_SYSCONFIG:
        case PDM_CTRL0:
        case PDM_CTRL1:
        case PDM_CLK_CTRL:
        case PDM_HPF_CTRL:
        case PDM_FIFO_CTRL:
        case PDM_DMA_CTRL:
        case PDM_INT_EN:
        case PDM_INT_CLR:
        case PDM_DATA_VALID:
                return true;
        default:
                return false;
        }
}

static bool rockchip_pdm_rd_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case PDM_SYSCONFIG:
        case PDM_CTRL0:
        case PDM_CTRL1:
        case PDM_CLK_CTRL:
        case PDM_HPF_CTRL:
        case PDM_FIFO_CTRL:
        case PDM_DMA_CTRL:
        case PDM_INT_EN:
        case PDM_INT_CLR:
        case PDM_INT_ST:
        case PDM_DATA_VALID:
        case PDM_RXFIFO_DATA:
        case PDM_VERSION:
                return true;
        default:
                return false;
        }
}

static bool rockchip_pdm_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case PDM_SYSCONFIG:
        case PDM_FIFO_CTRL:
        case PDM_INT_CLR:
        case PDM_INT_ST:
        case PDM_RXFIFO_DATA:
                return true;
        default:
                return false;
        }
}

static bool rockchip_pdm_precious_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case PDM_RXFIFO_DATA:
                return true;
        default:
                return false;
        }
}

static const struct reg_default rockchip_pdm_reg_defaults[] = {
        { PDM_CTRL0, 0x78000017 },
        { PDM_CTRL1, 0x0bb8ea60 },
        { PDM_CLK_CTRL, 0x0000e401 },
        { PDM_DMA_CTRL, 0x0000001f },
};

static const struct regmap_config rockchip_pdm_regmap_config = {
        .reg_bits = 32,
        .reg_stride = 4,
        .val_bits = 32,
        .max_register = PDM_VERSION,
        .reg_defaults = rockchip_pdm_reg_defaults,
        .num_reg_defaults = ARRAY_SIZE(rockchip_pdm_reg_defaults),
        .writeable_reg = rockchip_pdm_wr_reg,
        .readable_reg = rockchip_pdm_rd_reg,
        .volatile_reg = rockchip_pdm_volatile_reg,
        .precious_reg = rockchip_pdm_precious_reg,
        .cache_type = REGCACHE_FLAT,
};

static const struct of_device_id rockchip_pdm_match[] __maybe_unused = {
        { .compatible = "rockchip,pdm",
          .data = (void *)RK_PDM_RK3229 },
        { .compatible = "rockchip,px30-pdm",
          .data = (void *)RK_PDM_RK3308 },
        { .compatible = "rockchip,rk1808-pdm",
          .data = (void *)RK_PDM_RK3308 },
        { .compatible = "rockchip,rk3308-pdm",
          .data = (void *)RK_PDM_RK3308 },
        { .compatible = "rockchip,rk3568-pdm",
          .data = (void *)RK_PDM_RV1126 },
        { .compatible = "rockchip,rv1126-pdm",
          .data = (void *)RK_PDM_RV1126 },
        {},
};
MODULE_DEVICE_TABLE(of, rockchip_pdm_match);

static int rockchip_pdm_path_parse(struct rk_pdm_dev *pdm, struct device_node *node)
{
        unsigned int path[PDM_PATH_MAX];
        int cnt = 0, ret = 0, i = 0, val = 0, msk = 0;

        cnt = of_count_phandle_with_args(node, "rockchip,path-map",
                                         NULL);
        if (cnt != PDM_PATH_MAX)
                return cnt;

        ret = of_property_read_u32_array(node, "rockchip,path-map",
                                         path, cnt);
        if (ret)
                return ret;

        for (i = 0; i < cnt; i++) {
                if (path[i] >= PDM_PATH_MAX)
                        return -EINVAL;
                msk |= PDM_PATH_MASK(i);
                val |= PDM_PATH(i, path[i]);
        }

        regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, msk, val);

        return 0;
}

static int rockchip_pdm_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct rk_pdm_dev *pdm;
        struct resource *res;
        void __iomem *regs;
        int ret;

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

        pdm->version = (unsigned long)device_get_match_data(&pdev->dev);
        if (pdm->version == RK_PDM_RK3308) {
                pdm->reset = devm_reset_control_get(&pdev->dev, "pdm-m");
                if (IS_ERR(pdm->reset))
                        return PTR_ERR(pdm->reset);
        }

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

        pdm->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
                                            &rockchip_pdm_regmap_config);
        if (IS_ERR(pdm->regmap))
                return PTR_ERR(pdm->regmap);

        pdm->capture_dma_data.addr = res->start + PDM_RXFIFO_DATA;
        pdm->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
        pdm->capture_dma_data.maxburst = PDM_DMA_BURST_SIZE;

        pdm->dev = &pdev->dev;
        dev_set_drvdata(&pdev->dev, pdm);

        pdm->clk = devm_clk_get(&pdev->dev, "pdm_clk");
        if (IS_ERR(pdm->clk))
                return PTR_ERR(pdm->clk);

        pdm->hclk = devm_clk_get(&pdev->dev, "pdm_hclk");
        if (IS_ERR(pdm->hclk))
                return PTR_ERR(pdm->hclk);

        ret = clk_prepare_enable(pdm->hclk);
        if (ret)
                return ret;

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

        ret = devm_snd_soc_register_component(&pdev->dev,
                                              &rockchip_pdm_component,
                                              &rockchip_pdm_dai, 1);

        if (ret) {
                dev_err(&pdev->dev, "could not register dai: %d\n", ret);
                goto err_suspend;
        }

        rockchip_pdm_rxctrl(pdm, 0);

        ret = rockchip_pdm_path_parse(pdm, node);
        if (ret != 0 && ret != -ENOENT)
                goto err_suspend;

        ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
        if (ret) {
                dev_err(&pdev->dev, "could not register pcm: %d\n", ret);
                goto err_suspend;
        }

        return 0;

err_suspend:
        if (!pm_runtime_status_suspended(&pdev->dev))
                rockchip_pdm_runtime_suspend(&pdev->dev);
err_pm_disable:
        pm_runtime_disable(&pdev->dev);

        clk_disable_unprepare(pdm->hclk);

        return ret;
}

static void rockchip_pdm_remove(struct platform_device *pdev)
{
        struct rk_pdm_dev *pdm = dev_get_drvdata(&pdev->dev);

        pm_runtime_disable(&pdev->dev);
        if (!pm_runtime_status_suspended(&pdev->dev))
                rockchip_pdm_runtime_suspend(&pdev->dev);

        clk_disable_unprepare(pdm->clk);
        clk_disable_unprepare(pdm->hclk);
}

static int rockchip_pdm_suspend(struct device *dev)
{
        struct rk_pdm_dev *pdm = dev_get_drvdata(dev);

        regcache_mark_dirty(pdm->regmap);

        return 0;
}

static int rockchip_pdm_resume(struct device *dev)
{
        struct rk_pdm_dev *pdm = dev_get_drvdata(dev);
        int ret;

        ret = pm_runtime_resume_and_get(dev);
        if (ret < 0)
                return ret;

        ret = regcache_sync(pdm->regmap);

        pm_runtime_put(dev);

        return ret;
}

static const struct dev_pm_ops rockchip_pdm_pm_ops = {
        RUNTIME_PM_OPS(rockchip_pdm_runtime_suspend,
                       rockchip_pdm_runtime_resume, NULL)
        SYSTEM_SLEEP_PM_OPS(rockchip_pdm_suspend, rockchip_pdm_resume)
};

static struct platform_driver rockchip_pdm_driver = {
        .probe  = rockchip_pdm_probe,
        .remove = rockchip_pdm_remove,
        .driver = {
                .name = "rockchip-pdm",
                .of_match_table = of_match_ptr(rockchip_pdm_match),
                .pm = pm_ptr(&rockchip_pdm_pm_ops),
        },
};

module_platform_driver(rockchip_pdm_driver);

MODULE_AUTHOR("Sugar <sugar.zhang@rock-chips.com>");
MODULE_DESCRIPTION("Rockchip PDM Controller Driver");
MODULE_LICENSE("GPL v2");