spdif_out.c

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/*
 * ALSA SoC SPDIF Out Audio Layer for spear processors
 *
 * Copyright (C) 2012 ST Microelectronics
 * Vipin Kumar <[email protected]>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <sound/soc.h>
#include <sound/spear_dma.h>
#include <sound/spear_spdif.h>
#include "spdif_out_regs.h"

struct spdif_out_params {
    u32 rate;
    u32 core_freq;
    u32 mute;
};

struct spdif_out_dev {
    struct clk *clk;
    struct spear_dma_data dma_params;
    struct spdif_out_params saved_params;
    u32 running;
    void __iomem *io_base;
};

static void spdif_out_configure(struct spdif_out_dev *host)
{
    writel(SPDIF_OUT_RESET, host->io_base + SPDIF_OUT_SOFT_RST);
    mdelay(1);
    writel(readl(host->io_base + SPDIF_OUT_SOFT_RST) & ~SPDIF_OUT_RESET,
            host->io_base + SPDIF_OUT_SOFT_RST);

    writel(SPDIF_OUT_FDMA_TRIG_16 | SPDIF_OUT_MEMFMT_16_16 |
            SPDIF_OUT_VALID_HW | SPDIF_OUT_USER_HW |
            SPDIF_OUT_CHNLSTA_HW | SPDIF_OUT_PARITY_HW,
            host->io_base + SPDIF_OUT_CFG);

    writel(0x7F, host->io_base + SPDIF_OUT_INT_STA_CLR);
    writel(0x7F, host->io_base + SPDIF_OUT_INT_EN_CLR);
}

static int spdif_out_startup(struct snd_pcm_substream *substream,
        struct snd_soc_dai *cpu_dai)
{
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(cpu_dai);
    int ret;

    if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
        return -EINVAL;

    snd_soc_dai_set_dma_data(cpu_dai, substream, (void *)&host->dma_params);

    ret = clk_enable(host->clk);
    if (ret)
        return ret;

    host->running = true;
    spdif_out_configure(host);

    return 0;
}

static void spdif_out_shutdown(struct snd_pcm_substream *substream,
        struct snd_soc_dai *dai)
{
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(dai);

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

    clk_disable(host->clk);
    host->running = false;
    snd_soc_dai_set_dma_data(dai, substream, NULL);
}

static void spdif_out_clock(struct spdif_out_dev *host, u32 core_freq,
        u32 rate)
{
    u32 divider, ctrl;

    clk_set_rate(host->clk, core_freq);
    divider = DIV_ROUND_CLOSEST(clk_get_rate(host->clk), (rate * 128));

    ctrl = readl(host->io_base + SPDIF_OUT_CTRL);
    ctrl &= ~SPDIF_DIVIDER_MASK;
    ctrl |= (divider << SPDIF_DIVIDER_SHIFT) & SPDIF_DIVIDER_MASK;
    writel(ctrl, host->io_base + SPDIF_OUT_CTRL);
}

static int spdif_out_hw_params(struct snd_pcm_substream *substream,
        struct snd_pcm_hw_params *params,
        struct snd_soc_dai *dai)
{
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(dai);
    u32 rate, core_freq;

    if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
        return -EINVAL;

    rate = params_rate(params);

    switch (rate) {
    case 8000:
    case 16000:
    case 32000:
    case 64000:
        /*
         * The clock is multiplied by 10 to bring it to feasible range
         * of frequencies for sscg
         */
        core_freq = 64000 * 128 * 10;   /* 81.92 MHz */
        break;
    case 5512:
    case 11025:
    case 22050:
    case 44100:
    case 88200:
    case 176400:
        core_freq = 176400 * 128;   /* 22.5792 MHz */
        break;
    case 48000:
    case 96000:
    case 192000:
    default:
        core_freq = 192000 * 128;   /* 24.576 MHz */
        break;
    }

    spdif_out_clock(host, core_freq, rate);
    host->saved_params.core_freq = core_freq;
    host->saved_params.rate = rate;

    return 0;
}

static int spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
        struct snd_soc_dai *dai)
{
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(dai);
    u32 ctrl;
    int ret = 0;

    if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
        return -EINVAL;

    switch (cmd) {
    case SNDRV_PCM_TRIGGER_START:
    case SNDRV_PCM_TRIGGER_RESUME:
    case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
            ctrl = readl(host->io_base + SPDIF_OUT_CTRL);
            ctrl &= ~SPDIF_OPMODE_MASK;
            if (!host->saved_params.mute)
                ctrl |= SPDIF_OPMODE_AUD_DATA |
                    SPDIF_STATE_NORMAL;
            else
                ctrl |= SPDIF_OPMODE_MUTE_PCM;
            writel(ctrl, host->io_base + SPDIF_OUT_CTRL);
        break;

    case SNDRV_PCM_TRIGGER_STOP:
    case SNDRV_PCM_TRIGGER_SUSPEND:
    case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
        ctrl = readl(host->io_base + SPDIF_OUT_CTRL);
        ctrl &= ~SPDIF_OPMODE_MASK;
        ctrl |= SPDIF_OPMODE_OFF;
        writel(ctrl, host->io_base + SPDIF_OUT_CTRL);
        break;

    default:
        ret = -EINVAL;
        break;
    }
    return ret;
}

static int spdif_digital_mute(struct snd_soc_dai *dai, int mute)
{
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(dai);
    u32 val;

    host->saved_params.mute = mute;
    val = readl(host->io_base + SPDIF_OUT_CTRL);
    val &= ~SPDIF_OPMODE_MASK;

    if (mute)
        val |= SPDIF_OPMODE_MUTE_PCM;
    else {
        if (host->running)
            val |= SPDIF_OPMODE_AUD_DATA | SPDIF_STATE_NORMAL;
        else
            val |= SPDIF_OPMODE_OFF;
    }

    writel(val, host->io_base + SPDIF_OUT_CTRL);
    return 0;
}

static int spdif_mute_get(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct snd_soc_card *card = codec->card;
    struct snd_soc_pcm_runtime *rtd = card->rtd;
    struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(cpu_dai);

    ucontrol->value.integer.value[0] = host->saved_params.mute;
    return 0;
}

static int spdif_mute_put(struct snd_kcontrol *kcontrol,
        struct snd_ctl_elem_value *ucontrol)
{
    struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol);
    struct snd_soc_card *card = codec->card;
    struct snd_soc_pcm_runtime *rtd = card->rtd;
    struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
    struct spdif_out_dev *host = snd_soc_dai_get_drvdata(cpu_dai);

    if (host->saved_params.mute == ucontrol->value.integer.value[0])
        return 0;

    spdif_digital_mute(cpu_dai, ucontrol->value.integer.value[0]);

    return 1;
}
static const struct snd_kcontrol_new spdif_out_controls[] = {
    SOC_SINGLE_BOOL_EXT("IEC958 Playback Switch", 0,
            spdif_mute_get, spdif_mute_put),
};

int spdif_soc_dai_probe(struct snd_soc_dai *dai)
{
    return snd_soc_add_dai_controls(dai, spdif_out_controls,
                ARRAY_SIZE(spdif_out_controls));
}

static const struct snd_soc_dai_ops spdif_out_dai_ops = {
    .digital_mute   = spdif_digital_mute,
    .startup    = spdif_out_startup,
    .shutdown   = spdif_out_shutdown,
    .trigger    = spdif_out_trigger,
    .hw_params  = spdif_out_hw_params,
};

static struct snd_soc_dai_driver spdif_out_dai = {
    .playback = {
        .channels_min = 2,
        .channels_max = 2,
        .rates = (SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
                 SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000 | \
                 SNDRV_PCM_RATE_192000),
        .formats = SNDRV_PCM_FMTBIT_S16_LE,
    },
    .probe = spdif_soc_dai_probe,
    .ops = &spdif_out_dai_ops,
};

static int spdif_out_probe(struct platform_device *pdev)
{
    struct spdif_out_dev *host;
    struct spear_spdif_platform_data *pdata;
    struct resource *res;
    int ret;

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res)
        return -EINVAL;

    if (!devm_request_mem_region(&pdev->dev, res->start,
                resource_size(res), pdev->name)) {
        dev_warn(&pdev->dev, "Failed to get memory resourse\n");
        return -ENOENT;
    }

    host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
    if (!host) {
        dev_warn(&pdev->dev, "kzalloc fail\n");
        return -ENOMEM;
    }

    host->io_base = devm_ioremap(&pdev->dev, res->start,
                resource_size(res));
    if (!host->io_base) {
        dev_warn(&pdev->dev, "ioremap failed\n");
        return -ENOMEM;
    }

    host->clk = clk_get(&pdev->dev, NULL);
    if (IS_ERR(host->clk))
        return PTR_ERR(host->clk);

    pdata = dev_get_platdata(&pdev->dev);

    host->dma_params.data = pdata->dma_params;
    host->dma_params.addr = res->start + SPDIF_OUT_FIFO_DATA;
    host->dma_params.max_burst = 16;
    host->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
    host->dma_params.filter = pdata->filter;

    dev_set_drvdata(&pdev->dev, host);

    ret = snd_soc_register_dai(&pdev->dev, &spdif_out_dai);
    if (ret != 0) {
        clk_put(host->clk);
        return ret;
    }

    return 0;
}

static int spdif_out_remove(struct platform_device *pdev)
{
    struct spdif_out_dev *host = dev_get_drvdata(&pdev->dev);

    snd_soc_unregister_dai(&pdev->dev);
    dev_set_drvdata(&pdev->dev, NULL);

    clk_put(host->clk);

    return 0;
}

#ifdef CONFIG_PM
static int spdif_out_suspend(struct device *dev)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct spdif_out_dev *host = dev_get_drvdata(&pdev->dev);

    if (host->running)
        clk_disable(host->clk);

    return 0;
}

static int spdif_out_resume(struct device *dev)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct spdif_out_dev *host = dev_get_drvdata(&pdev->dev);

    if (host->running) {
        clk_enable(host->clk);
        spdif_out_configure(host);
        spdif_out_clock(host, host->saved_params.core_freq,
                host->saved_params.rate);
    }
    return 0;
}

static SIMPLE_DEV_PM_OPS(spdif_out_dev_pm_ops, spdif_out_suspend, \
        spdif_out_resume);

#define SPDIF_OUT_DEV_PM_OPS (&spdif_out_dev_pm_ops)

#else
#define SPDIF_OUT_DEV_PM_OPS NULL

#endif

static struct platform_driver spdif_out_driver = {
    .probe      = spdif_out_probe,
    .remove     = spdif_out_remove,
    .driver     = {
        .name   = "spdif-out",
        .owner  = THIS_MODULE,
        .pm = SPDIF_OUT_DEV_PM_OPS,
    },
};

module_platform_driver(spdif_out_driver);

MODULE_AUTHOR("Vipin Kumar <[email protected]>");
MODULE_DESCRIPTION("SPEAr SPDIF OUT SoC Interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:spdif_out");