/*
 * ALSA SoC SPDIF Out Audio Layer for spear processors
 *
 * Copyright (C) 2012 ST Microelectronics
 * Vipin Kumar <vipin.kumar@st.com>
 *
 * 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/dmaengine_pcm.h>
#include <sound/soc.h>
#include <sound/spear_dma.h>
#include <sound/spear_spdif.h>
#include "spdif_out_regs.h"
#include "spear_pcm.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;
        struct snd_dmaengine_dai_dma_data dma_params_tx;
        struct snd_dmaengine_pcm_config config;
};

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;

        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;
}

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_mute(struct snd_soc_dai *dai, int mute, int direction)
{
        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_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
        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_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
        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_mute(cpu_dai, ucontrol->value.integer.value[0],
                   SNDRV_PCM_STREAM_PLAYBACK);

        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),
};

static int spdif_soc_dai_probe(struct snd_soc_dai *dai)
{
        struct spdif_out_dev *host = snd_soc_dai_get_drvdata(dai);

        host->dma_params_tx.filter_data = &host->dma_params;

        snd_soc_dai_dma_data_set_playback(dai, &host->dma_params_tx);

        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 = {
        .mute_stream    = spdif_mute,
        .startup        = spdif_out_startup,
        .shutdown       = spdif_out_shutdown,
        .trigger        = spdif_out_trigger,
        .hw_params      = spdif_out_hw_params,
        .no_capture_mute = 1,
};

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 const struct snd_soc_component_driver spdif_out_component = {
        .name                   = "spdif-out",
        .legacy_dai_naming      = 1,
};

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;

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

        host->io_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
        if (IS_ERR(host->io_base))
                return PTR_ERR(host->io_base);

        host->clk = devm_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;

        dev_set_drvdata(&pdev->dev, host);

        ret = devm_snd_soc_register_component(&pdev->dev, &spdif_out_component,
                                              &spdif_out_dai, 1);
        if (ret)
                return ret;

        return devm_spear_pcm_platform_register(&pdev->dev, &host->config,
                                                pdata->filter);
}

#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,
        .driver         = {
                .name   = "spdif-out",
                .pm     = SPDIF_OUT_DEV_PM_OPS,
        },
};

module_platform_driver(spdif_out_driver);

MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>");
MODULE_DESCRIPTION("SPEAr SPDIF OUT SoC Interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:spdif_out");