/*
   * 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 "davinci-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 davinci_pcm_dma_params	dma_params[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;
  	struct davinci_pcm_dma_params *dma_params =
  			&davinci_vcif_dev->dma_params[substream->stream];
  	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:
  		dma_params->data_type = 0;
  
  		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:
  		dma_params->data_type = 1;
  
  		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:
  		dma_params->data_type = 2;
  
  		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;
  	}
  
  	dma_params->acnt  = dma_params->data_type;
  
  	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;
  }
  
  static int davinci_vcif_startup(struct snd_pcm_substream *substream,
  				struct snd_soc_dai *dai)
  {
  	struct davinci_vcif_dev *dev = snd_soc_dai_get_drvdata(dai);
  
  	snd_soc_dai_set_dma_data(dai, substream, dev->dma_params);
  	return 0;
  }
  
  #define DAVINCI_VCIF_RATES	SNDRV_PCM_RATE_8000_48000
  
  static const struct snd_soc_dai_ops davinci_vcif_dai_ops = {
  	.startup	= davinci_vcif_startup,
  	.trigger	= davinci_vcif_trigger,
  	.hw_params	= davinci_vcif_hw_params,
  };
  
  static struct snd_soc_dai_driver davinci_vcif_dai = {
  	.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
  ");
  		return -ENOMEM;
  	}
  
  	/* DMA tx params */
  	davinci_vcif_dev->davinci_vc = davinci_vc;
  	davinci_vcif_dev->dma_params[SNDRV_PCM_STREAM_PLAYBACK].channel =
  					davinci_vc->davinci_vcif.dma_tx_channel;
  	davinci_vcif_dev->dma_params[SNDRV_PCM_STREAM_PLAYBACK].dma_addr =
  					davinci_vc->davinci_vcif.dma_tx_addr;
  
  	/* DMA rx params */
  	davinci_vcif_dev->dma_params[SNDRV_PCM_STREAM_CAPTURE].channel =
  					davinci_vc->davinci_vcif.dma_rx_channel;
  	davinci_vcif_dev->dma_params[SNDRV_PCM_STREAM_CAPTURE].dma_addr =
  					davinci_vc->davinci_vcif.dma_rx_addr;
  
  	dev_set_drvdata(&pdev->dev, davinci_vcif_dev);
  
  	ret = snd_soc_register_component(&pdev->dev, &davinci_vcif_component,
  					 &davinci_vcif_dai, 1);
  	if (ret != 0) {
  		dev_err(&pdev->dev, "could not register dai
  ");
  		return ret;
  	}
  
  	ret = davinci_soc_platform_register(&pdev->dev);
  	if (ret) {
  		dev_err(&pdev->dev, "register PCM failed: %d
  ", ret);
  		snd_soc_unregister_component(&pdev->dev);
  		return ret;
  	}
  
  	return 0;
  }
  
  static int davinci_vcif_remove(struct platform_device *pdev)
  {
  	snd_soc_unregister_component(&pdev->dev);
  	davinci_soc_platform_unregister(&pdev->dev);
  
  	return 0;
  }
  
  static struct platform_driver davinci_vcif_driver = {
  	.probe		= davinci_vcif_probe,
  	.remove		= davinci_vcif_remove,
  	.driver		= {
  		.name	= "davinci-vcif",
  		.owner	= THIS_MODULE,
  	},
  };
  
  module_platform_driver(davinci_vcif_driver);
  
  MODULE_AUTHOR("Miguel Aguilar");
  MODULE_DESCRIPTION("Texas Instruments DaVinci ASoC Voice Codec Interface");
  MODULE_LICENSE("GPL");