/*
 * ALSA SoC Voice Codec Interface for TI DAVINCI processor
 *
 * Copyright (C) 2010 Texas Instruments.
 *
 * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/mfd/davinci_voicecodec.h>

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

#include "edma-pcm.h"
#include "davinci-i2s.h"

#define MOD_REG_BIT(val, mask, set) do { \
        if (set) { \
                val |= mask; \
        } else { \
                val &= ~mask; \
        } \
} while (0)

struct davinci_vcif_dev {
        struct davinci_vc *davinci_vc;
        struct snd_dmaengine_dai_dma_data dma_data[2];
        int dma_request[2];
};

static void davinci_vcif_start(struct snd_pcm_substream *substream)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct davinci_vcif_dev *davinci_vcif_dev =
                        snd_soc_dai_get_drvdata(rtd->cpu_dai);
        struct davinci_vc *davinci_vc = davinci_vcif_dev->davinci_vc;
        u32 w;

        /* Start the sample generator and enable transmitter/receiver */
        w = readl(davinci_vc->base + DAVINCI_VC_CTRL);

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RSTDAC, 0);
        else
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RSTADC, 0);

        writel(w, davinci_vc->base + DAVINCI_VC_CTRL);
}

static void davinci_vcif_stop(struct snd_pcm_substream *substream)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct davinci_vcif_dev *davinci_vcif_dev =
                        snd_soc_dai_get_drvdata(rtd->cpu_dai);
        struct davinci_vc *davinci_vc = davinci_vcif_dev->davinci_vc;
        u32 w;

        /* Reset transmitter/receiver and sample rate/frame sync generators */
        w = readl(davinci_vc->base + DAVINCI_VC_CTRL);
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RSTDAC, 1);
        else
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RSTADC, 1);

        writel(w, davinci_vc->base + DAVINCI_VC_CTRL);
}

static int davinci_vcif_hw_params(struct snd_pcm_substream *substream,
                                  struct snd_pcm_hw_params *params,
                                  struct snd_soc_dai *dai)
{
        struct davinci_vcif_dev *davinci_vcif_dev = snd_soc_dai_get_drvdata(dai);
        struct davinci_vc *davinci_vc = davinci_vcif_dev->davinci_vc;
        u32 w;

        /* Restart the codec before setup */
        davinci_vcif_stop(substream);
        davinci_vcif_start(substream);

        /* General line settings */
        writel(DAVINCI_VC_CTRL_MASK, davinci_vc->base + DAVINCI_VC_CTRL);

        writel(DAVINCI_VC_INT_MASK, davinci_vc->base + DAVINCI_VC_INTCLR);

        writel(DAVINCI_VC_INT_MASK, davinci_vc->base + DAVINCI_VC_INTEN);

        w = readl(davinci_vc->base + DAVINCI_VC_CTRL);

        /* Determine xfer data type */
        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_U8:
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RD_BITS_8 |
                            DAVINCI_VC_CTRL_RD_UNSIGNED |
                            DAVINCI_VC_CTRL_WD_BITS_8 |
                            DAVINCI_VC_CTRL_WD_UNSIGNED, 1);
                break;
        case SNDRV_PCM_FORMAT_S8:
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RD_BITS_8 |
                            DAVINCI_VC_CTRL_WD_BITS_8, 1);

                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RD_UNSIGNED |
                            DAVINCI_VC_CTRL_WD_UNSIGNED, 0);
                break;
        case SNDRV_PCM_FORMAT_S16_LE:
                MOD_REG_BIT(w, DAVINCI_VC_CTRL_RD_BITS_8 |
                            DAVINCI_VC_CTRL_RD_UNSIGNED |
                            DAVINCI_VC_CTRL_WD_BITS_8 |
                            DAVINCI_VC_CTRL_WD_UNSIGNED, 0);
                break;
        default:
                printk(KERN_WARNING "davinci-vcif: unsupported PCM format");
                return -EINVAL;
        }

        writel(w, davinci_vc->base + DAVINCI_VC_CTRL);

        return 0;
}

static int davinci_vcif_trigger(struct snd_pcm_substream *substream, int cmd,
                                struct snd_soc_dai *dai)
{
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                davinci_vcif_start(substream);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                davinci_vcif_stop(substream);
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

#define DAVINCI_VCIF_RATES      SNDRV_PCM_RATE_8000_48000

static const struct snd_soc_dai_ops davinci_vcif_dai_ops = {
        .trigger        = davinci_vcif_trigger,
        .hw_params      = davinci_vcif_hw_params,
};

static int davinci_vcif_dai_probe(struct snd_soc_dai *dai)
{
        struct davinci_vcif_dev *dev = snd_soc_dai_get_drvdata(dai);

        dai->playback_dma_data = &dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK];
        dai->capture_dma_data = &dev->dma_data[SNDRV_PCM_STREAM_CAPTURE];

        return 0;
}

static struct snd_soc_dai_driver davinci_vcif_dai = {
        .probe = davinci_vcif_dai_probe,
        .playback = {
                .channels_min = 1,
                .channels_max = 2,
                .rates = DAVINCI_VCIF_RATES,
                .formats = SNDRV_PCM_FMTBIT_S16_LE,},
        .capture = {
                .channels_min = 1,
                .channels_max = 2,
                .rates = DAVINCI_VCIF_RATES,
                .formats = SNDRV_PCM_FMTBIT_S16_LE,},
        .ops = &davinci_vcif_dai_ops,

};

static const struct snd_soc_component_driver davinci_vcif_component = {
        .name           = "davinci-vcif",
};

static int davinci_vcif_probe(struct platform_device *pdev)
{
        struct davinci_vc *davinci_vc = pdev->dev.platform_data;
        struct davinci_vcif_dev *davinci_vcif_dev;
        int ret;

        davinci_vcif_dev = devm_kzalloc(&pdev->dev,
                                        sizeof(struct davinci_vcif_dev),
                                        GFP_KERNEL);
        if (!davinci_vcif_dev) {
                dev_dbg(&pdev->dev,
                        "could not allocate memory for private data\n");
                return -ENOMEM;
        }

        /* DMA tx params */
        davinci_vcif_dev->davinci_vc = davinci_vc;
        davinci_vcif_dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data =
                                &davinci_vc->davinci_vcif.dma_tx_channel;
        davinci_vcif_dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr =
                                davinci_vc->davinci_vcif.dma_tx_addr;

        /* DMA rx params */
        davinci_vcif_dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].filter_data =
                                &davinci_vc->davinci_vcif.dma_rx_channel;
        davinci_vcif_dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr =
                                davinci_vc->davinci_vcif.dma_rx_addr;

        dev_set_drvdata(&pdev->dev, davinci_vcif_dev);

        ret = devm_snd_soc_register_component(&pdev->dev,
                                              &davinci_vcif_component,
                                              &davinci_vcif_dai, 1);
        if (ret != 0) {
                dev_err(&pdev->dev, "could not register dai\n");
                return ret;
        }

        ret = edma_pcm_platform_register(&pdev->dev);
        if (ret) {
                dev_err(&pdev->dev, "register PCM failed: %d\n", ret);
                return ret;
        }

        return 0;
}

static struct platform_driver davinci_vcif_driver = {
        .probe          = davinci_vcif_probe,
        .driver         = {
                .name   = "davinci-vcif",
        },
};

module_platform_driver(davinci_vcif_driver);

MODULE_AUTHOR("Miguel Aguilar");
MODULE_DESCRIPTION("Texas Instruments DaVinci ASoC Voice Codec Interface");
MODULE_LICENSE("GPL");