root/sound/soc/img/img-i2s-in.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * IMG I2S input controller driver
 *
 * Copyright (C) 2015 Imagination Technologies Ltd.
 *
 * Author: Damien Horsley <Damien.Horsley@imgtec.com>
 */

#include <linux/clk.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>

#include <sound/core.h>
#include <sound/dmaengine_pcm.h>
#include <sound/initval.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#define IMG_I2S_IN_RX_FIFO                      0x0

#define IMG_I2S_IN_CTL                          0x4
#define IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK         0xfffffffc
#define IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT          2
#define IMG_I2S_IN_CTL_16PACK_MASK              BIT(1)
#define IMG_I2S_IN_CTL_ME_MASK                  BIT(0)

#define IMG_I2S_IN_CH_CTL                       0x4
#define IMG_I2S_IN_CH_CTL_CCDEL_MASK            0x38000
#define IMG_I2S_IN_CH_CTL_CCDEL_SHIFT           15
#define IMG_I2S_IN_CH_CTL_FEN_MASK              BIT(14)
#define IMG_I2S_IN_CH_CTL_FMODE_MASK            BIT(13)
#define IMG_I2S_IN_CH_CTL_16PACK_MASK           BIT(12)
#define IMG_I2S_IN_CH_CTL_JUST_MASK             BIT(10)
#define IMG_I2S_IN_CH_CTL_PACKH_MASK            BIT(9)
#define IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK        BIT(8)
#define IMG_I2S_IN_CH_CTL_BLKP_MASK             BIT(7)
#define IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK       BIT(6)
#define IMG_I2S_IN_CH_CTL_LRD_MASK              BIT(3)
#define IMG_I2S_IN_CH_CTL_FW_MASK               BIT(2)
#define IMG_I2S_IN_CH_CTL_SW_MASK               BIT(1)
#define IMG_I2S_IN_CH_CTL_ME_MASK               BIT(0)

#define IMG_I2S_IN_CH_STRIDE                    0x20

struct img_i2s_in {
        void __iomem *base;
        struct clk *clk_sys;
        struct snd_dmaengine_dai_dma_data dma_data;
        struct device *dev;
        unsigned int max_i2s_chan;
        void __iomem *channel_base;
        unsigned int active_channels;
        struct snd_soc_dai_driver dai_driver;
        u32 suspend_ctl;
        u32 *suspend_ch_ctl;
};

static int img_i2s_in_runtime_suspend(struct device *dev)
{
        struct img_i2s_in *i2s = dev_get_drvdata(dev);

        clk_disable_unprepare(i2s->clk_sys);

        return 0;
}

static int img_i2s_in_runtime_resume(struct device *dev)
{
        struct img_i2s_in *i2s = dev_get_drvdata(dev);
        int ret;

        ret = clk_prepare_enable(i2s->clk_sys);
        if (ret) {
                dev_err(dev, "Unable to enable sys clock\n");
                return ret;
        }

        return 0;
}

static inline void img_i2s_in_writel(struct img_i2s_in *i2s, u32 val, u32 reg)
{
        writel(val, i2s->base + reg);
}

static inline u32 img_i2s_in_readl(struct img_i2s_in *i2s, u32 reg)
{
        return readl(i2s->base + reg);
}

static inline void img_i2s_in_ch_writel(struct img_i2s_in *i2s, u32 chan,
                                        u32 val, u32 reg)
{
        writel(val, i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
}

static inline u32 img_i2s_in_ch_readl(struct img_i2s_in *i2s, u32 chan,
                                        u32 reg)
{
        return readl(i2s->channel_base + (chan * IMG_I2S_IN_CH_STRIDE) + reg);
}

static inline void img_i2s_in_ch_disable(struct img_i2s_in *i2s, u32 chan)
{
        u32 reg;

        reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
        reg &= ~IMG_I2S_IN_CH_CTL_ME_MASK;
        img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
}

static inline void img_i2s_in_ch_enable(struct img_i2s_in *i2s, u32 chan)
{
        u32 reg;

        reg = img_i2s_in_ch_readl(i2s, chan, IMG_I2S_IN_CH_CTL);
        reg |= IMG_I2S_IN_CH_CTL_ME_MASK;
        img_i2s_in_ch_writel(i2s, chan, reg, IMG_I2S_IN_CH_CTL);
}

static inline void img_i2s_in_disable(struct img_i2s_in *i2s)
{
        u32 reg;

        reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
        reg &= ~IMG_I2S_IN_CTL_ME_MASK;
        img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
}

static inline void img_i2s_in_enable(struct img_i2s_in *i2s)
{
        u32 reg;

        reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
        reg |= IMG_I2S_IN_CTL_ME_MASK;
        img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);
}

static inline void img_i2s_in_flush(struct img_i2s_in *i2s)
{
        int i;
        u32 reg;

        for (i = 0; i < i2s->active_channels; i++) {
                reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
                reg |= IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
                reg &= ~IMG_I2S_IN_CH_CTL_FIFO_FLUSH_MASK;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
        }
}

static int img_i2s_in_trigger(struct snd_pcm_substream *substream, int cmd,
        struct snd_soc_dai *dai)
{
        struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                img_i2s_in_enable(i2s);
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                img_i2s_in_disable(i2s);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int img_i2s_in_check_rate(struct img_i2s_in *i2s,
                unsigned int sample_rate, unsigned int frame_size,
                unsigned int *bclk_filter_enable,
                unsigned int *bclk_filter_value)
{
        unsigned int bclk_freq, cur_freq;

        bclk_freq = sample_rate * frame_size;

        cur_freq = clk_get_rate(i2s->clk_sys);

        if (cur_freq >= bclk_freq * 8) {
                *bclk_filter_enable = 1;
                *bclk_filter_value = 0;
        } else if (cur_freq >= bclk_freq * 7) {
                *bclk_filter_enable = 1;
                *bclk_filter_value = 1;
        } else if (cur_freq >= bclk_freq * 6) {
                *bclk_filter_enable = 0;
                *bclk_filter_value = 0;
        } else {
                dev_err(i2s->dev,
                        "Sys clock rate %u insufficient for sample rate %u\n",
                        cur_freq, sample_rate);
                return -EINVAL;
        }

        return 0;
}

static int img_i2s_in_hw_params(struct snd_pcm_substream *substream,
        struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
{
        struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
        unsigned int rate, channels, i2s_channels, frame_size;
        unsigned int bclk_filter_enable, bclk_filter_value;
        int i, ret = 0;
        u32 reg, control_mask, chan_control_mask;
        u32 control_set = 0, chan_control_set = 0;
        snd_pcm_format_t format;

        rate = params_rate(params);
        format = params_format(params);
        channels = params_channels(params);
        i2s_channels = channels / 2;

        switch (format) {
        case SNDRV_PCM_FORMAT_S32_LE:
                frame_size = 64;
                chan_control_set |= IMG_I2S_IN_CH_CTL_SW_MASK;
                chan_control_set |= IMG_I2S_IN_CH_CTL_FW_MASK;
                chan_control_set |= IMG_I2S_IN_CH_CTL_PACKH_MASK;
                break;
        case SNDRV_PCM_FORMAT_S24_LE:
                frame_size = 64;
                chan_control_set |= IMG_I2S_IN_CH_CTL_SW_MASK;
                chan_control_set |= IMG_I2S_IN_CH_CTL_FW_MASK;
                break;
        case SNDRV_PCM_FORMAT_S16_LE:
                frame_size = 32;
                control_set |= IMG_I2S_IN_CTL_16PACK_MASK;
                chan_control_set |= IMG_I2S_IN_CH_CTL_16PACK_MASK;
                break;
        default:
                return -EINVAL;
        }

        if ((channels < 2) ||
            (channels > (i2s->max_i2s_chan * 2)) ||
            (channels % 2))
                return -EINVAL;

        control_set |= ((i2s_channels - 1) << IMG_I2S_IN_CTL_ACTIVE_CH_SHIFT);

        ret = img_i2s_in_check_rate(i2s, rate, frame_size,
                        &bclk_filter_enable, &bclk_filter_value);
        if (ret < 0)
                return ret;

        if (bclk_filter_enable)
                chan_control_set |= IMG_I2S_IN_CH_CTL_FEN_MASK;

        if (bclk_filter_value)
                chan_control_set |= IMG_I2S_IN_CH_CTL_FMODE_MASK;

        control_mask = IMG_I2S_IN_CTL_16PACK_MASK |
                       IMG_I2S_IN_CTL_ACTIVE_CHAN_MASK;

        chan_control_mask = IMG_I2S_IN_CH_CTL_16PACK_MASK |
                            IMG_I2S_IN_CH_CTL_FEN_MASK |
                            IMG_I2S_IN_CH_CTL_FMODE_MASK |
                            IMG_I2S_IN_CH_CTL_SW_MASK |
                            IMG_I2S_IN_CH_CTL_FW_MASK |
                            IMG_I2S_IN_CH_CTL_PACKH_MASK;

        reg = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);
        reg = (reg & ~control_mask) | control_set;
        img_i2s_in_writel(i2s, reg, IMG_I2S_IN_CTL);

        for (i = 0; i < i2s->active_channels; i++)
                img_i2s_in_ch_disable(i2s, i);

        for (i = 0; i < i2s->max_i2s_chan; i++) {
                reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
                reg = (reg & ~chan_control_mask) | chan_control_set;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
        }

        i2s->active_channels = i2s_channels;

        img_i2s_in_flush(i2s);

        for (i = 0; i < i2s->active_channels; i++)
                img_i2s_in_ch_enable(i2s, i);

        return 0;
}

static int img_i2s_in_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
{
        struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);
        int i, ret;
        u32 chan_control_mask, lrd_set = 0, blkp_set = 0, chan_control_set = 0;
        u32 reg;

        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
        case SND_SOC_DAIFMT_NB_NF:
                lrd_set |= IMG_I2S_IN_CH_CTL_LRD_MASK;
                break;
        case SND_SOC_DAIFMT_NB_IF:
                break;
        case SND_SOC_DAIFMT_IB_NF:
                lrd_set |= IMG_I2S_IN_CH_CTL_LRD_MASK;
                blkp_set |= IMG_I2S_IN_CH_CTL_BLKP_MASK;
                break;
        case SND_SOC_DAIFMT_IB_IF:
                blkp_set |= IMG_I2S_IN_CH_CTL_BLKP_MASK;
                break;
        default:
                return -EINVAL;
        }

        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_I2S:
                chan_control_set |= IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                break;
        default:
                return -EINVAL;
        }

        switch (fmt & SND_SOC_DAIFMT_CLOCK_PROVIDER_MASK) {
        case SND_SOC_DAIFMT_BC_FC:
                break;
        default:
                return -EINVAL;
        }

        chan_control_mask = IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;

        ret = pm_runtime_resume_and_get(i2s->dev);
        if (ret < 0)
                return ret;

        for (i = 0; i < i2s->active_channels; i++)
                img_i2s_in_ch_disable(i2s, i);

        /*
         * BLKP and LRD must be set during separate register writes
         */
        for (i = 0; i < i2s->max_i2s_chan; i++) {
                reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
                reg = (reg & ~chan_control_mask) | chan_control_set;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
                reg = (reg & ~IMG_I2S_IN_CH_CTL_BLKP_MASK) | blkp_set;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
                reg = (reg & ~IMG_I2S_IN_CH_CTL_LRD_MASK) | lrd_set;
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
        }

        for (i = 0; i < i2s->active_channels; i++)
                img_i2s_in_ch_enable(i2s, i);

        pm_runtime_put(i2s->dev);

        return 0;
}

static int img_i2s_in_dai_probe(struct snd_soc_dai *dai)
{
        struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai);

        snd_soc_dai_init_dma_data(dai, NULL, &i2s->dma_data);

        return 0;
}

static const struct snd_soc_dai_ops img_i2s_in_dai_ops = {
        .probe          = img_i2s_in_dai_probe,
        .trigger        = img_i2s_in_trigger,
        .hw_params      = img_i2s_in_hw_params,
        .set_fmt        = img_i2s_in_set_fmt
};

static const struct snd_soc_component_driver img_i2s_in_component = {
        .name = "img-i2s-in",
        .legacy_dai_naming = 1,
};

static int img_i2s_in_dma_prepare_slave_config(struct snd_pcm_substream *st,
        struct snd_pcm_hw_params *params, struct dma_slave_config *sc)
{
        unsigned int i2s_channels = params_channels(params) / 2;
        struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(st);
        struct snd_dmaengine_dai_dma_data *dma_data;
        int ret;

        dma_data = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), st);

        ret = snd_hwparams_to_dma_slave_config(st, params, sc);
        if (ret)
                return ret;

        sc->src_addr = dma_data->addr;
        sc->src_addr_width = dma_data->addr_width;
        sc->src_maxburst = 4 * i2s_channels;

        return 0;
}

static const struct snd_dmaengine_pcm_config img_i2s_in_dma_config = {
        .prepare_slave_config = img_i2s_in_dma_prepare_slave_config
};

static int img_i2s_in_probe(struct platform_device *pdev)
{
        struct img_i2s_in *i2s;
        struct resource *res;
        void __iomem *base;
        int ret, i;
        struct reset_control *rst;
        unsigned int max_i2s_chan_pow_2;
        struct device *dev = &pdev->dev;

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

        platform_set_drvdata(pdev, i2s);

        i2s->dev = dev;

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

        i2s->base = base;

        if (of_property_read_u32(pdev->dev.of_node, "img,i2s-channels",
                        &i2s->max_i2s_chan)) {
                dev_err(dev, "No img,i2s-channels property\n");
                return -EINVAL;
        }

        max_i2s_chan_pow_2 = 1 << get_count_order(i2s->max_i2s_chan);

        i2s->channel_base = base + (max_i2s_chan_pow_2 * 0x20);

        i2s->clk_sys = devm_clk_get(dev, "sys");
        if (IS_ERR(i2s->clk_sys))
                return dev_err_probe(dev, PTR_ERR(i2s->clk_sys),
                                     "Failed to acquire clock 'sys'\n");

        pm_runtime_enable(&pdev->dev);
        if (!pm_runtime_enabled(&pdev->dev)) {
                ret = img_i2s_in_runtime_resume(&pdev->dev);
                if (ret)
                        goto err_pm_disable;
        }
        ret = pm_runtime_resume_and_get(&pdev->dev);
        if (ret < 0)
                goto err_suspend;

        i2s->active_channels = 1;
        i2s->dma_data.addr = res->start + IMG_I2S_IN_RX_FIFO;
        i2s->dma_data.addr_width = 4;

        i2s->dai_driver.capture.channels_min = 2;
        i2s->dai_driver.capture.channels_max = i2s->max_i2s_chan * 2;
        i2s->dai_driver.capture.rates = SNDRV_PCM_RATE_8000_192000;
        i2s->dai_driver.capture.formats = SNDRV_PCM_FMTBIT_S32_LE |
                SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S16_LE;
        i2s->dai_driver.ops = &img_i2s_in_dai_ops;

        rst = devm_reset_control_get_exclusive(dev, "rst");
        if (IS_ERR(rst)) {
                if (PTR_ERR(rst) == -EPROBE_DEFER) {
                        ret = -EPROBE_DEFER;
                        pm_runtime_put(&pdev->dev);
                        goto err_suspend;
                }

                dev_dbg(dev, "No top level reset found\n");

                img_i2s_in_disable(i2s);

                for (i = 0; i < i2s->max_i2s_chan; i++)
                        img_i2s_in_ch_disable(i2s, i);
        } else {
                reset_control_assert(rst);
                reset_control_deassert(rst);
        }

        img_i2s_in_writel(i2s, 0, IMG_I2S_IN_CTL);

        for (i = 0; i < i2s->max_i2s_chan; i++)
                img_i2s_in_ch_writel(i2s, i,
                        (4 << IMG_I2S_IN_CH_CTL_CCDEL_SHIFT) |
                        IMG_I2S_IN_CH_CTL_JUST_MASK |
                        IMG_I2S_IN_CH_CTL_FW_MASK, IMG_I2S_IN_CH_CTL);

        pm_runtime_put(&pdev->dev);

        i2s->suspend_ch_ctl = devm_kcalloc(dev,
                i2s->max_i2s_chan, sizeof(*i2s->suspend_ch_ctl), GFP_KERNEL);
        if (!i2s->suspend_ch_ctl) {
                ret = -ENOMEM;
                goto err_suspend;
        }

        ret = devm_snd_soc_register_component(dev, &img_i2s_in_component,
                                                &i2s->dai_driver, 1);
        if (ret)
                goto err_suspend;

        ret = devm_snd_dmaengine_pcm_register(dev, &img_i2s_in_dma_config, 0);
        if (ret)
                goto err_suspend;

        return 0;

err_suspend:
        if (!pm_runtime_enabled(&pdev->dev))
                img_i2s_in_runtime_suspend(&pdev->dev);
err_pm_disable:
        pm_runtime_disable(&pdev->dev);

        return ret;
}

static void img_i2s_in_dev_remove(struct platform_device *pdev)
{
        pm_runtime_disable(&pdev->dev);
        if (!pm_runtime_status_suspended(&pdev->dev))
                img_i2s_in_runtime_suspend(&pdev->dev);
}

static int img_i2s_in_suspend(struct device *dev)
{
        struct img_i2s_in *i2s = dev_get_drvdata(dev);
        int i, ret;
        u32 reg;

        if (pm_runtime_status_suspended(dev)) {
                ret = img_i2s_in_runtime_resume(dev);
                if (ret)
                        return ret;
        }

        for (i = 0; i < i2s->max_i2s_chan; i++) {
                reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL);
                i2s->suspend_ch_ctl[i] = reg;
        }

        i2s->suspend_ctl = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);

        img_i2s_in_runtime_suspend(dev);

        return 0;
}

static int img_i2s_in_resume(struct device *dev)
{
        struct img_i2s_in *i2s = dev_get_drvdata(dev);
        int i, ret;
        u32 reg;

        ret = img_i2s_in_runtime_resume(dev);
        if (ret)
                return ret;

        for (i = 0; i < i2s->max_i2s_chan; i++) {
                reg = i2s->suspend_ch_ctl[i];
                img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL);
        }

        img_i2s_in_writel(i2s, i2s->suspend_ctl, IMG_I2S_IN_CTL);

        if (pm_runtime_status_suspended(dev))
                img_i2s_in_runtime_suspend(dev);

        return 0;
}

static const struct of_device_id img_i2s_in_of_match[] = {
        { .compatible = "img,i2s-in" },
        {}
};
MODULE_DEVICE_TABLE(of, img_i2s_in_of_match);

static const struct dev_pm_ops img_i2s_in_pm_ops = {
        RUNTIME_PM_OPS(img_i2s_in_runtime_suspend, img_i2s_in_runtime_resume, NULL)
        SYSTEM_SLEEP_PM_OPS(img_i2s_in_suspend, img_i2s_in_resume)
};

static struct platform_driver img_i2s_in_driver = {
        .driver = {
                .name = "img-i2s-in",
                .of_match_table = img_i2s_in_of_match,
                .pm = pm_ptr(&img_i2s_in_pm_ops)
        },
        .probe = img_i2s_in_probe,
        .remove = img_i2s_in_dev_remove
};
module_platform_driver(img_i2s_in_driver);

MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
MODULE_DESCRIPTION("IMG I2S Input Driver");
MODULE_LICENSE("GPL v2");