root/sound/soc/rockchip/rockchip_i2s.c
// SPDX-License-Identifier: GPL-2.0-only
/* sound/soc/rockchip/rockchip_i2s.c
 *
 * ALSA SoC Audio Layer - Rockchip I2S Controller driver
 *
 * Copyright (c) 2014 Rockchip Electronics Co. Ltd.
 * Author: Jianqun <jay.xu@rock-chips.com>
 */

#include <linux/module.h>
#include <linux/mfd/syscon.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/clk.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
#include <sound/pcm_params.h>
#include <sound/dmaengine_pcm.h>

#include "rockchip_i2s.h"

#define DRV_NAME "rockchip-i2s"

struct rk_i2s_pins {
        u32 reg_offset;
        u32 shift;
};

struct rk_i2s_dev {
        struct device *dev;

        struct clk *hclk;
        struct clk *mclk;

        struct snd_dmaengine_dai_dma_data capture_dma_data;
        struct snd_dmaengine_dai_dma_data playback_dma_data;

        struct regmap *regmap;
        struct regmap *grf;

        bool has_capture;
        bool has_playback;

/*
 * Used to indicate the tx/rx status.
 * I2S controller hopes to start the tx and rx together,
 * also to stop them when they are both try to stop.
*/
        bool tx_start;
        bool rx_start;
        bool is_master_mode;
        const struct rk_i2s_pins *pins;
        unsigned int bclk_ratio;
        spinlock_t lock; /* tx/rx lock */
        struct pinctrl *pinctrl;
        struct pinctrl_state *bclk_on;
        struct pinctrl_state *bclk_off;
};

static int i2s_pinctrl_select_bclk_on(struct rk_i2s_dev *i2s)
{
        int ret = 0;

        if (!IS_ERR(i2s->pinctrl) && !IS_ERR_OR_NULL(i2s->bclk_on))
                ret = pinctrl_select_state(i2s->pinctrl, i2s->bclk_on);

        if (ret)
                dev_err(i2s->dev, "bclk enable failed %d\n", ret);

        return ret;
}

static int i2s_pinctrl_select_bclk_off(struct rk_i2s_dev *i2s)
{

        int ret = 0;

        if (!IS_ERR(i2s->pinctrl) && !IS_ERR_OR_NULL(i2s->bclk_off))
                ret = pinctrl_select_state(i2s->pinctrl, i2s->bclk_off);

        if (ret)
                dev_err(i2s->dev, "bclk disable failed %d\n", ret);

        return ret;
}

static int i2s_runtime_suspend(struct device *dev)
{
        struct rk_i2s_dev *i2s = dev_get_drvdata(dev);

        regcache_cache_only(i2s->regmap, true);
        clk_disable_unprepare(i2s->mclk);

        return 0;
}

static int i2s_runtime_resume(struct device *dev)
{
        struct rk_i2s_dev *i2s = dev_get_drvdata(dev);
        int ret;

        ret = clk_prepare_enable(i2s->mclk);
        if (ret) {
                dev_err(i2s->dev, "clock enable failed %d\n", ret);
                return ret;
        }

        regcache_cache_only(i2s->regmap, false);
        regcache_mark_dirty(i2s->regmap);

        ret = regcache_sync(i2s->regmap);
        if (ret)
                clk_disable_unprepare(i2s->mclk);

        return ret;
}

static inline struct rk_i2s_dev *to_info(struct snd_soc_dai *dai)
{
        return snd_soc_dai_get_drvdata(dai);
}

static int rockchip_snd_txctrl(struct rk_i2s_dev *i2s, int on)
{
        unsigned int val = 0;
        int ret = 0;

        spin_lock(&i2s->lock);
        if (on) {
                ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
                                         I2S_DMACR_TDE_ENABLE,
                                         I2S_DMACR_TDE_ENABLE);
                if (ret < 0)
                        goto end;
                ret = regmap_update_bits(i2s->regmap, I2S_XFER,
                                         I2S_XFER_TXS_START | I2S_XFER_RXS_START,
                                         I2S_XFER_TXS_START | I2S_XFER_RXS_START);
                if (ret < 0)
                        goto end;
                i2s->tx_start = true;
        } else {
                i2s->tx_start = false;

                ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
                                         I2S_DMACR_TDE_ENABLE,
                                         I2S_DMACR_TDE_DISABLE);
                if (ret < 0)
                        goto end;

                if (!i2s->rx_start) {
                        ret = regmap_update_bits(i2s->regmap, I2S_XFER,
                                                 I2S_XFER_TXS_START | I2S_XFER_RXS_START,
                                                 I2S_XFER_TXS_STOP | I2S_XFER_RXS_STOP);
                        if (ret < 0)
                                goto end;
                        udelay(150);
                        ret = regmap_update_bits(i2s->regmap, I2S_CLR,
                                                 I2S_CLR_TXC | I2S_CLR_RXC,
                                                 I2S_CLR_TXC | I2S_CLR_RXC);
                        if (ret < 0)
                                goto end;
                        ret = regmap_read_poll_timeout_atomic(i2s->regmap,
                                                              I2S_CLR,
                                                              val,
                                                              val == 0,
                                                              20,
                                                              200);
                        if (ret < 0)
                                dev_warn(i2s->dev, "fail to clear: %d\n", ret);
                }
        }
end:
        spin_unlock(&i2s->lock);
        if (ret < 0)
                dev_err(i2s->dev, "lrclk update failed\n");

        return ret;
}

static int rockchip_snd_rxctrl(struct rk_i2s_dev *i2s, int on)
{
        unsigned int val = 0;
        int ret = 0;

        spin_lock(&i2s->lock);
        if (on) {
                ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
                                         I2S_DMACR_RDE_ENABLE,
                                         I2S_DMACR_RDE_ENABLE);
                if (ret < 0)
                        goto end;

                ret = regmap_update_bits(i2s->regmap, I2S_XFER,
                                         I2S_XFER_TXS_START | I2S_XFER_RXS_START,
                                         I2S_XFER_TXS_START | I2S_XFER_RXS_START);
                if (ret < 0)
                        goto end;
                i2s->rx_start = true;
        } else {
                i2s->rx_start = false;

                ret = regmap_update_bits(i2s->regmap, I2S_DMACR,
                                         I2S_DMACR_RDE_ENABLE,
                                         I2S_DMACR_RDE_DISABLE);
                if (ret < 0)
                        goto end;

                if (!i2s->tx_start) {
                        ret = regmap_update_bits(i2s->regmap, I2S_XFER,
                                                 I2S_XFER_TXS_START | I2S_XFER_RXS_START,
                                                 I2S_XFER_TXS_STOP | I2S_XFER_RXS_STOP);
                        if (ret < 0)
                                goto end;
                        udelay(150);
                        ret = regmap_update_bits(i2s->regmap, I2S_CLR,
                                                 I2S_CLR_TXC | I2S_CLR_RXC,
                                                 I2S_CLR_TXC | I2S_CLR_RXC);
                        if (ret < 0)
                                goto end;
                        ret = regmap_read_poll_timeout_atomic(i2s->regmap,
                                                              I2S_CLR,
                                                              val,
                                                              val == 0,
                                                              20,
                                                              200);
                        if (ret < 0)
                                dev_warn(i2s->dev, "fail to clear: %d\n", ret);
                }
        }
end:
        spin_unlock(&i2s->lock);
        if (ret < 0)
                dev_err(i2s->dev, "lrclk update failed\n");

        return ret;
}

static int rockchip_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
                                unsigned int fmt)
{
        struct rk_i2s_dev *i2s = to_info(cpu_dai);
        unsigned int mask = 0, val = 0;
        int ret = 0;

        pm_runtime_get_sync(cpu_dai->dev);
        mask = I2S_CKR_MSS_MASK;
        switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
        case SND_SOC_DAIFMT_BP_FP:
                /* Set source clock in Master mode */
                val = I2S_CKR_MSS_MASTER;
                i2s->is_master_mode = true;
                break;
        case SND_SOC_DAIFMT_BC_FC:
                val = I2S_CKR_MSS_SLAVE;
                i2s->is_master_mode = false;
                break;
        default:
                ret = -EINVAL;
                goto err_pm_put;
        }

        regmap_update_bits(i2s->regmap, I2S_CKR, mask, val);

        mask = I2S_CKR_CKP_MASK | I2S_CKR_TLP_MASK | I2S_CKR_RLP_MASK;
        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
        case SND_SOC_DAIFMT_NB_NF:
                val = I2S_CKR_CKP_NORMAL |
                      I2S_CKR_TLP_NORMAL |
                      I2S_CKR_RLP_NORMAL;
                break;
        case SND_SOC_DAIFMT_NB_IF:
                val = I2S_CKR_CKP_NORMAL |
                      I2S_CKR_TLP_INVERTED |
                      I2S_CKR_RLP_INVERTED;
                break;
        case SND_SOC_DAIFMT_IB_NF:
                val = I2S_CKR_CKP_INVERTED |
                      I2S_CKR_TLP_NORMAL |
                      I2S_CKR_RLP_NORMAL;
                break;
        case SND_SOC_DAIFMT_IB_IF:
                val = I2S_CKR_CKP_INVERTED |
                      I2S_CKR_TLP_INVERTED |
                      I2S_CKR_RLP_INVERTED;
                break;
        default:
                ret = -EINVAL;
                goto err_pm_put;
        }

        regmap_update_bits(i2s->regmap, I2S_CKR, mask, val);

        mask = I2S_TXCR_IBM_MASK | I2S_TXCR_TFS_MASK | I2S_TXCR_PBM_MASK;
        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_RIGHT_J:
                val = I2S_TXCR_IBM_RSJM;
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                val = I2S_TXCR_IBM_LSJM;
                break;
        case SND_SOC_DAIFMT_I2S:
                val = I2S_TXCR_IBM_NORMAL;
                break;
        case SND_SOC_DAIFMT_DSP_A: /* PCM delay 1 bit mode */
                val = I2S_TXCR_TFS_PCM | I2S_TXCR_PBM_MODE(1);
                break;
        case SND_SOC_DAIFMT_DSP_B: /* PCM no delay mode */
                val = I2S_TXCR_TFS_PCM;
                break;
        default:
                ret = -EINVAL;
                goto err_pm_put;
        }

        regmap_update_bits(i2s->regmap, I2S_TXCR, mask, val);

        mask = I2S_RXCR_IBM_MASK | I2S_RXCR_TFS_MASK | I2S_RXCR_PBM_MASK;
        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_RIGHT_J:
                val = I2S_RXCR_IBM_RSJM;
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                val = I2S_RXCR_IBM_LSJM;
                break;
        case SND_SOC_DAIFMT_I2S:
                val = I2S_RXCR_IBM_NORMAL;
                break;
        case SND_SOC_DAIFMT_DSP_A: /* PCM delay 1 bit mode */
                val = I2S_RXCR_TFS_PCM | I2S_RXCR_PBM_MODE(1);
                break;
        case SND_SOC_DAIFMT_DSP_B: /* PCM no delay mode */
                val = I2S_RXCR_TFS_PCM;
                break;
        default:
                ret = -EINVAL;
                goto err_pm_put;
        }

        regmap_update_bits(i2s->regmap, I2S_RXCR, mask, val);

err_pm_put:
        pm_runtime_put(cpu_dai->dev);

        return ret;
}

static int rockchip_i2s_hw_params(struct snd_pcm_substream *substream,
                                  struct snd_pcm_hw_params *params,
                                  struct snd_soc_dai *dai)
{
        struct rk_i2s_dev *i2s = to_info(dai);
        struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
        unsigned int val = 0;
        unsigned int mclk_rate, bclk_rate, div_bclk, div_lrck;

        if (i2s->is_master_mode) {
                mclk_rate = clk_get_rate(i2s->mclk);
                bclk_rate = i2s->bclk_ratio * params_rate(params);
                if (!bclk_rate)
                        return -EINVAL;

                div_bclk = DIV_ROUND_CLOSEST(mclk_rate, bclk_rate);
                div_lrck = bclk_rate / params_rate(params);
                regmap_update_bits(i2s->regmap, I2S_CKR,
                                   I2S_CKR_MDIV_MASK,
                                   I2S_CKR_MDIV(div_bclk));

                regmap_update_bits(i2s->regmap, I2S_CKR,
                                   I2S_CKR_TSD_MASK |
                                   I2S_CKR_RSD_MASK,
                                   I2S_CKR_TSD(div_lrck) |
                                   I2S_CKR_RSD(div_lrck));
        }

        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S8:
                val |= I2S_TXCR_VDW(8);
                break;
        case SNDRV_PCM_FORMAT_S16_LE:
                val |= I2S_TXCR_VDW(16);
                break;
        case SNDRV_PCM_FORMAT_S20_3LE:
                val |= I2S_TXCR_VDW(20);
                break;
        case SNDRV_PCM_FORMAT_S24_LE:
                val |= I2S_TXCR_VDW(24);
                break;
        case SNDRV_PCM_FORMAT_S32_LE:
                val |= I2S_TXCR_VDW(32);
                break;
        default:
                return -EINVAL;
        }

        switch (params_channels(params)) {
        case 8:
                val |= I2S_CHN_8;
                break;
        case 6:
                val |= I2S_CHN_6;
                break;
        case 4:
                val |= I2S_CHN_4;
                break;
        case 2:
                val |= I2S_CHN_2;
                break;
        default:
                dev_err(i2s->dev, "invalid channel: %d\n",
                        params_channels(params));
                return -EINVAL;
        }

        if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
                regmap_update_bits(i2s->regmap, I2S_RXCR,
                                   I2S_RXCR_VDW_MASK | I2S_RXCR_CSR_MASK,
                                   val);
        else
                regmap_update_bits(i2s->regmap, I2S_TXCR,
                                   I2S_TXCR_VDW_MASK | I2S_TXCR_CSR_MASK,
                                   val);

        if (!IS_ERR(i2s->grf) && i2s->pins) {
                regmap_read(i2s->regmap, I2S_TXCR, &val);
                val &= I2S_TXCR_CSR_MASK;

                switch (val) {
                case I2S_CHN_4:
                        val = I2S_IO_4CH_OUT_6CH_IN;
                        break;
                case I2S_CHN_6:
                        val = I2S_IO_6CH_OUT_4CH_IN;
                        break;
                case I2S_CHN_8:
                        val = I2S_IO_8CH_OUT_2CH_IN;
                        break;
                default:
                        val = I2S_IO_2CH_OUT_8CH_IN;
                        break;
                }

                val <<= i2s->pins->shift;
                val |= (I2S_IO_DIRECTION_MASK << i2s->pins->shift) << 16;
                regmap_write(i2s->grf, i2s->pins->reg_offset, val);
        }

        regmap_update_bits(i2s->regmap, I2S_DMACR, I2S_DMACR_TDL_MASK,
                           I2S_DMACR_TDL(16));
        regmap_update_bits(i2s->regmap, I2S_DMACR, I2S_DMACR_RDL_MASK,
                           I2S_DMACR_RDL(16));

        val = I2S_CKR_TRCM_TXRX;
        if (dai->driver->symmetric_rate && rtd->dai_link->symmetric_rate)
                val = I2S_CKR_TRCM_TXONLY;

        regmap_update_bits(i2s->regmap, I2S_CKR,
                           I2S_CKR_TRCM_MASK,
                           val);
        return 0;
}

static int rockchip_i2s_trigger(struct snd_pcm_substream *substream,
                                int cmd, struct snd_soc_dai *dai)
{
        struct rk_i2s_dev *i2s = 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)
                        ret = rockchip_snd_rxctrl(i2s, 1);
                else
                        ret = rockchip_snd_txctrl(i2s, 1);
                if (ret < 0)
                        return ret;
                i2s_pinctrl_select_bclk_on(i2s);
                break;
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
                        if (!i2s->tx_start)
                                i2s_pinctrl_select_bclk_off(i2s);
                        ret = rockchip_snd_rxctrl(i2s, 0);
                } else {
                        if (!i2s->rx_start)
                                i2s_pinctrl_select_bclk_off(i2s);
                        ret = rockchip_snd_txctrl(i2s, 0);
                }
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int rockchip_i2s_set_bclk_ratio(struct snd_soc_dai *dai,
                                       unsigned int ratio)
{
        struct rk_i2s_dev *i2s = to_info(dai);

        i2s->bclk_ratio = ratio;

        return 0;
}

static int rockchip_i2s_set_sysclk(struct snd_soc_dai *cpu_dai, int clk_id,
                                   unsigned int freq, int dir)
{
        struct rk_i2s_dev *i2s = to_info(cpu_dai);
        int ret;

        if (freq == 0)
                return 0;

        ret = clk_set_rate(i2s->mclk, freq);
        if (ret)
                dev_err(i2s->dev, "Fail to set mclk %d\n", ret);

        return ret;
}

static int rockchip_i2s_dai_probe(struct snd_soc_dai *dai)
{
        struct rk_i2s_dev *i2s = snd_soc_dai_get_drvdata(dai);

        snd_soc_dai_init_dma_data(dai,
                i2s->has_playback ? &i2s->playback_dma_data : NULL,
                i2s->has_capture  ? &i2s->capture_dma_data  : NULL);

        return 0;
}

static const struct snd_soc_dai_ops rockchip_i2s_dai_ops = {
        .probe = rockchip_i2s_dai_probe,
        .hw_params = rockchip_i2s_hw_params,
        .set_bclk_ratio = rockchip_i2s_set_bclk_ratio,
        .set_sysclk = rockchip_i2s_set_sysclk,
        .set_fmt = rockchip_i2s_set_fmt,
        .trigger = rockchip_i2s_trigger,
};

static struct snd_soc_dai_driver rockchip_i2s_dai = {
        .ops = &rockchip_i2s_dai_ops,
        .symmetric_rate = 1,
};

static const struct snd_soc_component_driver rockchip_i2s_component = {
        .name = DRV_NAME,
        .legacy_dai_naming = 1,
};

static bool rockchip_i2s_wr_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case I2S_TXCR:
        case I2S_RXCR:
        case I2S_CKR:
        case I2S_DMACR:
        case I2S_INTCR:
        case I2S_XFER:
        case I2S_CLR:
        case I2S_TXDR:
                return true;
        default:
                return false;
        }
}

static bool rockchip_i2s_rd_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case I2S_TXCR:
        case I2S_RXCR:
        case I2S_CKR:
        case I2S_DMACR:
        case I2S_INTCR:
        case I2S_XFER:
        case I2S_CLR:
        case I2S_TXDR:
        case I2S_RXDR:
        case I2S_FIFOLR:
        case I2S_INTSR:
                return true;
        default:
                return false;
        }
}

static bool rockchip_i2s_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case I2S_INTSR:
        case I2S_CLR:
        case I2S_FIFOLR:
        case I2S_TXDR:
        case I2S_RXDR:
                return true;
        default:
                return false;
        }
}

static bool rockchip_i2s_precious_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case I2S_RXDR:
                return true;
        default:
                return false;
        }
}

static const struct reg_default rockchip_i2s_reg_defaults[] = {
        {0x00, 0x0000000f},
        {0x04, 0x0000000f},
        {0x08, 0x00071f1f},
        {0x10, 0x001f0000},
        {0x14, 0x01f00000},
};

static const struct regmap_config rockchip_i2s_regmap_config = {
        .reg_bits = 32,
        .reg_stride = 4,
        .val_bits = 32,
        .max_register = I2S_RXDR,
        .reg_defaults = rockchip_i2s_reg_defaults,
        .num_reg_defaults = ARRAY_SIZE(rockchip_i2s_reg_defaults),
        .writeable_reg = rockchip_i2s_wr_reg,
        .readable_reg = rockchip_i2s_rd_reg,
        .volatile_reg = rockchip_i2s_volatile_reg,
        .precious_reg = rockchip_i2s_precious_reg,
        .cache_type = REGCACHE_FLAT,
};

static const struct rk_i2s_pins rk3399_i2s_pins = {
        .reg_offset = 0xe220,
        .shift = 11,
};

static const struct of_device_id rockchip_i2s_match[] __maybe_unused = {
        { .compatible = "rockchip,px30-i2s", },
        { .compatible = "rockchip,rk1808-i2s", },
        { .compatible = "rockchip,rk3036-i2s", },
        { .compatible = "rockchip,rk3066-i2s", },
        { .compatible = "rockchip,rk3128-i2s", },
        { .compatible = "rockchip,rk3188-i2s", },
        { .compatible = "rockchip,rk3228-i2s", },
        { .compatible = "rockchip,rk3288-i2s", },
        { .compatible = "rockchip,rk3308-i2s", },
        { .compatible = "rockchip,rk3328-i2s", },
        { .compatible = "rockchip,rk3366-i2s", },
        { .compatible = "rockchip,rk3368-i2s", },
        { .compatible = "rockchip,rk3399-i2s", .data = &rk3399_i2s_pins },
        { .compatible = "rockchip,rk3588-i2s", },
        { .compatible = "rockchip,rv1126-i2s", },
        {},
};

static int rockchip_i2s_init_dai(struct rk_i2s_dev *i2s, struct resource *res,
                                 struct snd_soc_dai_driver **dp)
{
        struct device_node *node = i2s->dev->of_node;
        struct snd_soc_dai_driver *dai;
        struct property *dma_names;
        const char *dma_name;
        unsigned int val;

        of_property_for_each_string(node, "dma-names", dma_names, dma_name) {
                if (!strcmp(dma_name, "tx"))
                        i2s->has_playback = true;
                if (!strcmp(dma_name, "rx"))
                        i2s->has_capture = true;
        }

        dai = devm_kmemdup(i2s->dev, &rockchip_i2s_dai,
                           sizeof(*dai), GFP_KERNEL);
        if (!dai)
                return -ENOMEM;

        if (i2s->has_playback) {
                dai->playback.stream_name = "Playback";
                dai->playback.channels_min = 2;
                dai->playback.channels_max = 8;
                dai->playback.rates = SNDRV_PCM_RATE_8000_192000;
                dai->playback.formats = SNDRV_PCM_FMTBIT_S8 |
                                        SNDRV_PCM_FMTBIT_S16_LE |
                                        SNDRV_PCM_FMTBIT_S20_3LE |
                                        SNDRV_PCM_FMTBIT_S24_LE |
                                        SNDRV_PCM_FMTBIT_S32_LE;

                i2s->playback_dma_data.addr = res->start + I2S_TXDR;
                i2s->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
                i2s->playback_dma_data.maxburst = 8;

                if (!of_property_read_u32(node, "rockchip,playback-channels", &val)) {
                        if (val >= 2 && val <= 8)
                                dai->playback.channels_max = val;
                }
        }

        if (i2s->has_capture) {
                dai->capture.stream_name = "Capture";
                dai->capture.channels_min = 2;
                dai->capture.channels_max = 8;
                dai->capture.rates = SNDRV_PCM_RATE_8000_192000;
                dai->capture.formats = SNDRV_PCM_FMTBIT_S8 |
                                       SNDRV_PCM_FMTBIT_S16_LE |
                                       SNDRV_PCM_FMTBIT_S20_3LE |
                                       SNDRV_PCM_FMTBIT_S24_LE |
                                       SNDRV_PCM_FMTBIT_S32_LE;

                i2s->capture_dma_data.addr = res->start + I2S_RXDR;
                i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
                i2s->capture_dma_data.maxburst = 8;

                if (!of_property_read_u32(node, "rockchip,capture-channels", &val)) {
                        if (val >= 2 && val <= 8)
                                dai->capture.channels_max = val;
                }
        }

        if (dp)
                *dp = dai;

        return 0;
}

static int rockchip_i2s_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct rk_i2s_dev *i2s;
        struct snd_soc_dai_driver *dai;
        struct resource *res;
        void __iomem *regs;
        int ret;

        i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
        if (!i2s)
                return -ENOMEM;

        spin_lock_init(&i2s->lock);
        i2s->dev = &pdev->dev;

        i2s->grf = syscon_regmap_lookup_by_phandle(node, "rockchip,grf");
        if (!IS_ERR(i2s->grf)) {
                i2s->pins = device_get_match_data(&pdev->dev);
                if (!i2s->pins)
                        return -EINVAL;

        }

        /* try to prepare related clocks */
        i2s->hclk = devm_clk_get(&pdev->dev, "i2s_hclk");
        if (IS_ERR(i2s->hclk)) {
                dev_err(&pdev->dev, "Can't retrieve i2s bus clock\n");
                return PTR_ERR(i2s->hclk);
        }
        ret = clk_prepare_enable(i2s->hclk);
        if (ret) {
                dev_err(i2s->dev, "hclock enable failed %d\n", ret);
                return ret;
        }

        i2s->mclk = devm_clk_get(&pdev->dev, "i2s_clk");
        if (IS_ERR(i2s->mclk)) {
                dev_err(&pdev->dev, "Can't retrieve i2s master clock\n");
                ret = PTR_ERR(i2s->mclk);
                goto err_clk;
        }

        regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(regs)) {
                ret = PTR_ERR(regs);
                goto err_clk;
        }

        i2s->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
                                            &rockchip_i2s_regmap_config);
        if (IS_ERR(i2s->regmap)) {
                dev_err(&pdev->dev,
                        "Failed to initialise managed register map\n");
                ret = PTR_ERR(i2s->regmap);
                goto err_clk;
        }

        i2s->bclk_ratio = 64;
        i2s->pinctrl = devm_pinctrl_get(&pdev->dev);
        if (!IS_ERR(i2s->pinctrl)) {
                i2s->bclk_on = pinctrl_lookup_state(i2s->pinctrl, "bclk_on");
                if (!IS_ERR_OR_NULL(i2s->bclk_on)) {
                        i2s->bclk_off = pinctrl_lookup_state(i2s->pinctrl, "bclk_off");
                        if (IS_ERR_OR_NULL(i2s->bclk_off)) {
                                dev_err(&pdev->dev, "failed to find i2s bclk_off\n");
                                ret = -EINVAL;
                                goto err_clk;
                        }
                }
        } else {
                dev_dbg(&pdev->dev, "failed to find i2s pinctrl\n");
        }

        i2s_pinctrl_select_bclk_off(i2s);

        dev_set_drvdata(&pdev->dev, i2s);

        pm_runtime_enable(&pdev->dev);
        if (!pm_runtime_enabled(&pdev->dev)) {
                ret = i2s_runtime_resume(&pdev->dev);
                if (ret)
                        goto err_pm_disable;
        }

        ret = rockchip_i2s_init_dai(i2s, res, &dai);
        if (ret)
                goto err_pm_disable;

        ret = devm_snd_soc_register_component(&pdev->dev,
                                              &rockchip_i2s_component,
                                              dai, 1);

        if (ret) {
                dev_err(&pdev->dev, "Could not register DAI\n");
                goto err_suspend;
        }

        ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
        if (ret) {
                dev_err(&pdev->dev, "Could not register PCM\n");
                goto err_suspend;
        }

        return 0;

err_suspend:
        if (!pm_runtime_status_suspended(&pdev->dev))
                i2s_runtime_suspend(&pdev->dev);
err_pm_disable:
        pm_runtime_disable(&pdev->dev);
err_clk:
        clk_disable_unprepare(i2s->hclk);
        return ret;
}

static void rockchip_i2s_remove(struct platform_device *pdev)
{
        struct rk_i2s_dev *i2s = dev_get_drvdata(&pdev->dev);

        pm_runtime_disable(&pdev->dev);
        if (!pm_runtime_status_suspended(&pdev->dev))
                i2s_runtime_suspend(&pdev->dev);

        clk_disable_unprepare(i2s->hclk);
}

static const struct dev_pm_ops rockchip_i2s_pm_ops = {
        RUNTIME_PM_OPS(i2s_runtime_suspend, i2s_runtime_resume, NULL)
};

static struct platform_driver rockchip_i2s_driver = {
        .probe = rockchip_i2s_probe,
        .remove = rockchip_i2s_remove,
        .driver = {
                .name = DRV_NAME,
                .of_match_table = of_match_ptr(rockchip_i2s_match),
                .pm = pm_ptr(&rockchip_i2s_pm_ops),
        },
};
module_platform_driver(rockchip_i2s_driver);

MODULE_DESCRIPTION("ROCKCHIP IIS ASoC Interface");
MODULE_AUTHOR("jianqun <jay.xu@rock-chips.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRV_NAME);
MODULE_DEVICE_TABLE(of, rockchip_i2s_match);