text: /*
   * File:         sound/soc/blackfin/bf5xx-ac97-pcm.c
   * Author:       Cliff Cai <Cliff.Cai@analog.com>
   *
   * Created:      Tue June 06 2008
   * Description:  DMA Driver for AC97 sound chip
   *
   * Modified:
   *               Copyright 2008 Analog Devices Inc.
   *
   * Bugs:         Enter bugs at http://blackfin.uclinux.org/
   *
   * 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, see the file COPYING, or write
   * to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/platform_device.h>
  #include <linux/dma-mapping.h>
  #include <linux/gfp.h>
  
  #include <sound/core.h>
  #include <sound/pcm.h>
  #include <sound/pcm_params.h>
  #include <sound/soc.h>
  
  #include <asm/dma.h>
  
  #include "bf5xx-ac97.h"
  #include "bf5xx-sport.h"
  
  static unsigned int ac97_chan_mask[] = {
  	SP_FL, /* Mono */
  	SP_STEREO, /* Stereo */
  	SP_2DOT1, /* 2.1*/
  	SP_QUAD,/*Quadraquic*/
  	SP_FL | SP_FR | SP_FC | SP_SL | SP_SR,/*5 channels */
  	SP_5DOT1, /* 5.1 */
  };
  
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  static void bf5xx_mmap_copy(struct snd_pcm_substream *substream,
  	 snd_pcm_uframes_t count)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	struct sport_device *sport = runtime->private_data;
  	unsigned int chan_mask = ac97_chan_mask[runtime->channels - 1];
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		bf5xx_pcm_to_ac97((struct ac97_frame *)sport->tx_dma_buf +
  		sport->tx_pos, (__u16 *)runtime->dma_area + sport->tx_pos *
  		runtime->channels, count, chan_mask);
  		sport->tx_pos += runtime->period_size;
  		if (sport->tx_pos >= runtime->buffer_size)
  			sport->tx_pos %= runtime->buffer_size;
  		sport->tx_delay_pos = sport->tx_pos;
  	} else {
  		bf5xx_ac97_to_pcm((struct ac97_frame *)sport->rx_dma_buf +
  		sport->rx_pos, (__u16 *)runtime->dma_area + sport->rx_pos *
  		runtime->channels, count);
  		sport->rx_pos += runtime->period_size;
  		if (sport->rx_pos >= runtime->buffer_size)
  			sport->rx_pos %= runtime->buffer_size;
  	}
  }
  #endif
  
  static void bf5xx_dma_irq(void *data)
  {
  	struct snd_pcm_substream *pcm = data;
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	struct snd_pcm_runtime *runtime = pcm->runtime;
  	struct sport_device *sport = runtime->private_data;
  	bf5xx_mmap_copy(pcm, runtime->period_size);
  	if (pcm->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		if (sport->once == 0) {
  			snd_pcm_period_elapsed(pcm);
  			bf5xx_mmap_copy(pcm, runtime->period_size);
  			sport->once = 1;
  		}
  	}
  #endif
  	snd_pcm_period_elapsed(pcm);
  }
  
  /* The memory size for pure pcm data is 128*1024 = 0x20000 bytes.
   * The total rx/tx buffer is for ac97 frame to hold all pcm data
   * is  0x20000 * sizeof(struct ac97_frame) / 4.
   */
  static const struct snd_pcm_hardware bf5xx_pcm_hardware = {
  	.info			= SNDRV_PCM_INFO_INTERLEAVED |
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  				   SNDRV_PCM_INFO_MMAP |
  				   SNDRV_PCM_INFO_MMAP_VALID |
  #endif
  				   SNDRV_PCM_INFO_BLOCK_TRANSFER,
  
  	.period_bytes_min	= 32,
  	.period_bytes_max	= 0x10000,
  	.periods_min		= 1,
  	.periods_max		= PAGE_SIZE/32,
  	.buffer_bytes_max	= 0x20000, /* 128 kbytes */
  	.fifo_size		= 16,
  };
  
  static int bf5xx_pcm_hw_params(struct snd_pcm_substream *substream,
  	struct snd_pcm_hw_params *params)
  {
  	size_t size = bf5xx_pcm_hardware.buffer_bytes_max
  			* sizeof(struct ac97_frame) / 4;
  
  	snd_pcm_lib_malloc_pages(substream, size);
  
  	return 0;
  }
  
  static int bf5xx_pcm_hw_free(struct snd_pcm_substream *substream)
  {
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	struct sport_device *sport = runtime->private_data;
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		sport->once = 0;
  		if (runtime->dma_area)
  			memset(runtime->dma_area, 0, runtime->buffer_size);
  		memset(sport->tx_dma_buf, 0, runtime->buffer_size *
  			sizeof(struct ac97_frame));
  	} else
  		memset(sport->rx_dma_buf, 0, runtime->buffer_size *
  			sizeof(struct ac97_frame));
  #endif
  	snd_pcm_lib_free_pages(substream);
  	return 0;
  }
  
  static int bf5xx_pcm_prepare(struct snd_pcm_substream *substream)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	struct sport_device *sport = runtime->private_data;
  
  	/* An intermediate buffer is introduced for implementing mmap for
  	 * SPORT working in TMD mode(include AC97).
  	 */
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		sport_set_tx_callback(sport, bf5xx_dma_irq, substream);
  		sport_config_tx_dma(sport, sport->tx_dma_buf, runtime->periods,
  			runtime->period_size * sizeof(struct ac97_frame));
  	} else {
  		sport_set_rx_callback(sport, bf5xx_dma_irq, substream);
  		sport_config_rx_dma(sport, sport->rx_dma_buf, runtime->periods,
  			runtime->period_size * sizeof(struct ac97_frame));
  	}
  #else
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		sport_set_tx_callback(sport, bf5xx_dma_irq, substream);
  		sport_config_tx_dma(sport, runtime->dma_area, runtime->periods,
  			runtime->period_size * sizeof(struct ac97_frame));
  	} else {
  		sport_set_rx_callback(sport, bf5xx_dma_irq, substream);
  		sport_config_rx_dma(sport, runtime->dma_area, runtime->periods,
  			runtime->period_size * sizeof(struct ac97_frame));
  	}
  #endif
  	return 0;
  }
  
  static int bf5xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	struct sport_device *sport = runtime->private_data;
  	int ret = 0;
  
  	pr_debug("%s enter\n", __func__);
  	switch (cmd) {
  	case SNDRV_PCM_TRIGGER_START:
  		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  			bf5xx_mmap_copy(substream, runtime->period_size);
  			sport->tx_delay_pos = 0;
  #endif
  			sport_tx_start(sport);
  		} else
  			sport_rx_start(sport);
  		break;
  	case SNDRV_PCM_TRIGGER_STOP:
  	case SNDRV_PCM_TRIGGER_SUSPEND:
  	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
  		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  			sport->tx_pos = 0;
  #endif
  			sport_tx_stop(sport);
  		} else {
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  			sport->rx_pos = 0;
  #endif
  			sport_rx_stop(sport);
  		}
  		break;
  	default:
  		ret = -EINVAL;
  	}
  	return ret;
  }
  
  static snd_pcm_uframes_t bf5xx_pcm_pointer(struct snd_pcm_substream *substream)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	struct sport_device *sport = runtime->private_data;
  	unsigned int curr;
  
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		curr = sport->tx_delay_pos;
  	else
  		curr = sport->rx_pos;
  #else
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		curr = sport_curr_offset_tx(sport) / sizeof(struct ac97_frame);
  	else
  		curr = sport_curr_offset_rx(sport) / sizeof(struct ac97_frame);
  
  #endif
  	return curr;
  }
  
  static int bf5xx_pcm_open(struct snd_pcm_substream *substream)
  {
  	struct snd_soc_pcm_runtime *rtd = substream->private_data;
  	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
  	struct sport_device *sport_handle = snd_soc_dai_get_drvdata(cpu_dai);
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	int ret;
  
  	pr_debug("%s enter\n", __func__);
  	snd_soc_set_runtime_hwparams(substream, &bf5xx_pcm_hardware);
  
  	ret = snd_pcm_hw_constraint_integer(runtime,
  					    SNDRV_PCM_HW_PARAM_PERIODS);
  	if (ret < 0)
  		goto out;
  
  	if (sport_handle != NULL)
  		runtime->private_data = sport_handle;
  	else {
  		pr_err("sport_handle is NULL\n");
  		return -1;
  	}
  	return 0;
  
   out:
  	return ret;
  }
  
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  static int bf5xx_pcm_mmap(struct snd_pcm_substream *substream,
  	struct vm_area_struct *vma)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	size_t size = vma->vm_end - vma->vm_start;
  	vma->vm_start = (unsigned long)runtime->dma_area;
  	vma->vm_end = vma->vm_start + size;
  	vma->vm_flags |=  VM_SHARED;
  	return 0 ;
  }
  #else
  static	int bf5xx_pcm_copy(struct snd_pcm_substream *substream, int channel,
  		    snd_pcm_uframes_t pos,
  		    void __user *buf, snd_pcm_uframes_t count)
  {
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	unsigned int chan_mask = ac97_chan_mask[runtime->channels - 1];
  	pr_debug("%s copy pos:0x%lx count:0x%lx\n",
  			substream->stream ? "Capture" : "Playback", pos, count);
  
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		bf5xx_pcm_to_ac97((struct ac97_frame *)runtime->dma_area + pos,
  			(__u16 *)buf, count, chan_mask);
  	else
  		bf5xx_ac97_to_pcm((struct ac97_frame *)runtime->dma_area + pos,
  			(__u16 *)buf, count);
  	return 0;
  }
  #endif
  
  static struct snd_pcm_ops bf5xx_pcm_ac97_ops = {
  	.open		= bf5xx_pcm_open,
  	.ioctl		= snd_pcm_lib_ioctl,
  	.hw_params	= bf5xx_pcm_hw_params,
  	.hw_free	= bf5xx_pcm_hw_free,
  	.prepare	= bf5xx_pcm_prepare,
  	.trigger	= bf5xx_pcm_trigger,
  	.pointer	= bf5xx_pcm_pointer,
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	.mmap		= bf5xx_pcm_mmap,
  #else
  	.copy		= bf5xx_pcm_copy,
  #endif
  };
  
  static int bf5xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
  {
  	struct snd_soc_pcm_runtime *rtd = pcm->private_data;
  	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
  	struct sport_device *sport_handle = snd_soc_dai_get_drvdata(cpu_dai);
  	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
  	struct snd_dma_buffer *buf = &substream->dma_buffer;
  	size_t size = bf5xx_pcm_hardware.buffer_bytes_max
  			* sizeof(struct ac97_frame) / 4;
  
  	buf->dev.type = SNDRV_DMA_TYPE_DEV;
  	buf->dev.dev = pcm->card->dev;
  	buf->private_data = NULL;
  	buf->area = dma_alloc_coherent(pcm->card->dev, size,
  			&buf->addr, GFP_KERNEL);
  	if (!buf->area) {
  		pr_err("Failed to allocate dma memory\n");
  		pr_err("Please increase uncached DMA memory region\n");
  		return -ENOMEM;
  	}
  	buf->bytes = size;
  
  	pr_debug("%s, area:%p, size:0x%08lx\n", __func__,
  			buf->area, buf->bytes);
  
  	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
  		sport_handle->tx_buf = buf->area;
  	else
  		sport_handle->rx_buf = buf->area;
  
  /*
   * Need to allocate local buffer when enable
   * MMAP for SPORT working in TMD mode (include AC97).
   */
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		if (!sport_handle->tx_dma_buf) {
  			sport_handle->tx_dma_buf = dma_alloc_coherent(NULL, \
  				size, &sport_handle->tx_dma_phy, GFP_KERNEL);
  			if (!sport_handle->tx_dma_buf) {
  				pr_err("Failed to allocate memory for tx dma buf - Please increase uncached DMA memory region\n");
  				return -ENOMEM;
  			} else
  				memset(sport_handle->tx_dma_buf, 0, size);
  		} else
  			memset(sport_handle->tx_dma_buf, 0, size);
  	} else {
  		if (!sport_handle->rx_dma_buf) {
  			sport_handle->rx_dma_buf = dma_alloc_coherent(NULL, \
  				size, &sport_handle->rx_dma_phy, GFP_KERNEL);
  			if (!sport_handle->rx_dma_buf) {
  				pr_err("Failed to allocate memory for rx dma buf - Please increase uncached DMA memory region\n");
  				return -ENOMEM;
  			} else
  				memset(sport_handle->rx_dma_buf, 0, size);
  		} else
  			memset(sport_handle->rx_dma_buf, 0, size);
  	}
  #endif
  	return 0;
  }
  
  static void bf5xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
  {
  	struct snd_pcm_substream *substream;
  	struct snd_dma_buffer *buf;
  	int stream;
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	struct snd_soc_pcm_runtime *rtd = pcm->private_data;
  	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
  	struct sport_device *sport_handle = snd_soc_dai_get_drvdata(cpu_dai);
  	size_t size = bf5xx_pcm_hardware.buffer_bytes_max *
  		sizeof(struct ac97_frame) / 4;
  #endif
  	for (stream = 0; stream < 2; stream++) {
  		substream = pcm->streams[stream].substream;
  		if (!substream)
  			continue;
  
  		buf = &substream->dma_buffer;
  		if (!buf->area)
  			continue;
  		dma_free_coherent(NULL, buf->bytes, buf->area, 0);
  		buf->area = NULL;
  #if defined(CONFIG_SND_BF5XX_MMAP_SUPPORT)
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  		if (sport_handle->tx_dma_buf)
  			dma_free_coherent(NULL, size, \
  				sport_handle->tx_dma_buf, 0);
  		sport_handle->tx_dma_buf = NULL;
  	} else {
  
  		if (sport_handle->rx_dma_buf)
  			dma_free_coherent(NULL, size, \
  				sport_handle->rx_dma_buf, 0);
  		sport_handle->rx_dma_buf = NULL;
  	}
  #endif
  	}
  }
  
  static int bf5xx_pcm_ac97_new(struct snd_soc_pcm_runtime *rtd)
  {
  	struct snd_card *card = rtd->card->snd_card;
  	struct snd_pcm *pcm = rtd->pcm;
  	int ret;
  
  	pr_debug("%s enter\n", __func__);
  	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
  	if (ret)
  		return ret;
  
  	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
  		ret = bf5xx_pcm_preallocate_dma_buffer(pcm,
  			SNDRV_PCM_STREAM_PLAYBACK);
  		if (ret)
  			goto out;
  	}
  
  	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
  		ret = bf5xx_pcm_preallocate_dma_buffer(pcm,
  			SNDRV_PCM_STREAM_CAPTURE);
  		if (ret)
  			goto out;
  	}
   out:
  	return ret;
  }
  
  static struct snd_soc_platform_driver bf5xx_ac97_soc_platform = {
  	.ops			= &bf5xx_pcm_ac97_ops,
  	.pcm_new	= bf5xx_pcm_ac97_new,
  	.pcm_free	= bf5xx_pcm_free_dma_buffers,
  };
  
  static int bf5xx_soc_platform_probe(struct platform_device *pdev)
  {
  	return snd_soc_register_platform(&pdev->dev, &bf5xx_ac97_soc_platform);
  }
  
  static int bf5xx_soc_platform_remove(struct platform_device *pdev)
  {
  	snd_soc_unregister_platform(&pdev->dev);
  	return 0;
  }
  
  static struct platform_driver bf5xx_pcm_driver = {
  	.driver = {
  			.name = "bfin-ac97-pcm-audio",
  			.owner = THIS_MODULE,
  	},
  
  	.probe = bf5xx_soc_platform_probe,
  	.remove = bf5xx_soc_platform_remove,
  };
  
  module_platform_driver(bf5xx_pcm_driver);
  
  MODULE_AUTHOR("Cliff Cai");
  MODULE_DESCRIPTION("ADI Blackfin AC97 PCM DMA module");
  MODULE_LICENSE("GPL");
  