sound/soc/txx9/txx9aclc.c - maze/linux - Git at Google

 /*
  * Generic TXx9 ACLC platform driver
  *
  * Copyright (C) 2009 Atsushi Nemoto
  *
  * Based on RBTX49xx patch from CELF patch archive.
  * (C) Copyright TOSHIBA CORPORATION 2004-2006
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
 #include "txx9aclc.h"

 static struct txx9aclc_soc_device {
 	struct txx9aclc_dmadata dmadata[2];
 } txx9aclc_soc_device;

 /* REVISIT: How to find txx9aclc_drvdata from snd_ac97? */
 static struct txx9aclc_plat_drvdata *txx9aclc_drvdata;

 static int txx9aclc_dma_init(struct txx9aclc_soc_device *dev,
 			     struct txx9aclc_dmadata *dmadata);

 static const struct snd_pcm_hardware txx9aclc_pcm_hardware = {
 	/*
 	 * REVISIT: SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
 	 * needs more works for noncoherent MIPS.
 	 */
 	.info		  = SNDRV_PCM_INFO_INTERLEAVED |
 			    SNDRV_PCM_INFO_BATCH |
 			    SNDRV_PCM_INFO_PAUSE,
 #ifdef __BIG_ENDIAN
 	.formats	  = SNDRV_PCM_FMTBIT_S16_BE,
 #else
 	.formats	  = SNDRV_PCM_FMTBIT_S16_LE,
 #endif
 	.period_bytes_min = 1024,
 	.period_bytes_max = 8 * 1024,
 	.periods_min	  = 2,
 	.periods_max	  = 4096,
 	.buffer_bytes_max = 32 * 1024,
 };

 static int txx9aclc_pcm_hw_params(struct snd_pcm_substream *substream,
 				  struct snd_pcm_hw_params *params)
 {
 	struct snd_soc_pcm_runtime *rtd = snd_pcm_substream_chip(substream);
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct txx9aclc_dmadata *dmadata = runtime->private_data;
 	int ret;

 	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
 	if (ret < 0)
 		return ret;

 	dev_dbg(rtd->platform->dev,
 		"runtime->dma_area = %#lx dma_addr = %#lx dma_bytes = %zd "
 		"runtime->min_align %ld\n",
 		(unsigned long)runtime->dma_area,
 		(unsigned long)runtime->dma_addr, runtime->dma_bytes,
 		runtime->min_align);
 	dev_dbg(rtd->platform->dev,
 		"periods %d period_bytes %d stream %d\n",
 		params_periods(params), params_period_bytes(params),
 		substream->stream);

 	dmadata->substream = substream;
 	dmadata->pos = 0;
 	return 0;
 }

 static int txx9aclc_pcm_hw_free(struct snd_pcm_substream *substream)
 {
 	return snd_pcm_lib_free_pages(substream);
 }

 static int txx9aclc_pcm_prepare(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	struct txx9aclc_dmadata *dmadata = runtime->private_data;

 	dmadata->dma_addr = runtime->dma_addr;
 	dmadata->buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
 	dmadata->period_bytes = snd_pcm_lib_period_bytes(substream);

 	if (dmadata->buffer_bytes == dmadata->period_bytes) {
 		dmadata->frag_bytes = dmadata->period_bytes >> 1;
 		dmadata->frags = 2;
 	} else {
 		dmadata->frag_bytes = dmadata->period_bytes;
 		dmadata->frags = dmadata->buffer_bytes / dmadata->period_bytes;
 	}
 	dmadata->frag_count = 0;
 	dmadata->pos = 0;
 	return 0;
 }

 static void txx9aclc_dma_complete(void *arg)
 {
 	struct txx9aclc_dmadata *dmadata = arg;
 	unsigned long flags;

 	/* dma completion handler cannot submit new operations */
 	spin_lock_irqsave(&dmadata->dma_lock, flags);
 	if (dmadata->frag_count >= 0) {
 		dmadata->dmacount--;
 		BUG_ON(dmadata->dmacount < 0);
 		tasklet_schedule(&dmadata->tasklet);
 	}
 	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 }

 static struct dma_async_tx_descriptor *
 txx9aclc_dma_submit(struct txx9aclc_dmadata *dmadata, dma_addr_t buf_dma_addr)
 {
 	struct dma_chan *chan = dmadata->dma_chan;
 	struct dma_async_tx_descriptor *desc;
 	struct scatterlist sg;

 	sg_init_table(&sg, 1);
 	sg_set_page(&sg, pfn_to_page(PFN_DOWN(buf_dma_addr)),
 		    dmadata->frag_bytes, buf_dma_addr & (PAGE_SIZE - 1));
 	sg_dma_address(&sg) = buf_dma_addr;
 	desc = chan->device->device_prep_slave_sg(chan, &sg, 1,
 		dmadata->substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
 		DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!desc) {
 		dev_err(&chan->dev->device, "cannot prepare slave dma\n");
 		return NULL;
 	}
 	desc->callback = txx9aclc_dma_complete;
 	desc->callback_param = dmadata;
 	desc->tx_submit(desc);
 	return desc;
 }

 #define NR_DMA_CHAIN		2

 static void txx9aclc_dma_tasklet(unsigned long data)
 {
 	struct txx9aclc_dmadata *dmadata = (struct txx9aclc_dmadata *)data;
 	struct dma_chan *chan = dmadata->dma_chan;
 	struct dma_async_tx_descriptor *desc;
 	struct snd_pcm_substream *substream = dmadata->substream;
 	u32 ctlbit = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
 		ACCTL_AUDODMA : ACCTL_AUDIDMA;
 	int i;
 	unsigned long flags;

 	spin_lock_irqsave(&dmadata->dma_lock, flags);
 	if (dmadata->frag_count < 0) {
 		struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
 		void __iomem *base = drvdata->base;

 		spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 		chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
 		/* first time */
 		for (i = 0; i < NR_DMA_CHAIN; i++) {
 			desc = txx9aclc_dma_submit(dmadata,
 				dmadata->dma_addr + i * dmadata->frag_bytes);
 			if (!desc)
 				return;
 		}
 		dmadata->dmacount = NR_DMA_CHAIN;
 		chan->device->device_issue_pending(chan);
 		spin_lock_irqsave(&dmadata->dma_lock, flags);
 		__raw_writel(ctlbit, base + ACCTLEN);
 		dmadata->frag_count = NR_DMA_CHAIN % dmadata->frags;
 		spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 		return;
 	}
 	BUG_ON(dmadata->dmacount >= NR_DMA_CHAIN);
 	while (dmadata->dmacount < NR_DMA_CHAIN) {
 		dmadata->dmacount++;
 		spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 		desc = txx9aclc_dma_submit(dmadata,
 			dmadata->dma_addr +
 			dmadata->frag_count * dmadata->frag_bytes);
 		if (!desc)
 			return;
 		chan->device->device_issue_pending(chan);

 		spin_lock_irqsave(&dmadata->dma_lock, flags);
 		dmadata->frag_count++;
 		dmadata->frag_count %= dmadata->frags;
 		dmadata->pos += dmadata->frag_bytes;
 		dmadata->pos %= dmadata->buffer_bytes;
 		if ((dmadata->frag_count * dmadata->frag_bytes) %
 		    dmadata->period_bytes == 0)
 			snd_pcm_period_elapsed(substream);
 	}
 	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 }

 static int txx9aclc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 {
 	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;
 	struct txx9aclc_plat_drvdata *drvdata =txx9aclc_drvdata;
 	void __iomem *base = drvdata->base;
 	unsigned long flags;
 	int ret = 0;
 	u32 ctlbit = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
 		ACCTL_AUDODMA : ACCTL_AUDIDMA;

 	spin_lock_irqsave(&dmadata->dma_lock, flags);
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 		dmadata->frag_count = -1;
 		tasklet_schedule(&dmadata->tasklet);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 		__raw_writel(ctlbit, base + ACCTLDIS);
 		break;
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 	case SNDRV_PCM_TRIGGER_RESUME:
 		__raw_writel(ctlbit, base + ACCTLEN);
 		break;
 	default:
 		ret = -EINVAL;
 	}
 	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
 	return ret;
 }

 static snd_pcm_uframes_t
 txx9aclc_pcm_pointer(struct snd_pcm_substream *substream)
 {
 	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;

 	return bytes_to_frames(substream->runtime, dmadata->pos);
 }

 static int txx9aclc_pcm_open(struct snd_pcm_substream *substream)
 {
 	struct txx9aclc_soc_device *dev = &txx9aclc_soc_device;
 	struct txx9aclc_dmadata *dmadata = &dev->dmadata[substream->stream];
 	int ret;

 	ret = snd_soc_set_runtime_hwparams(substream, &txx9aclc_pcm_hardware);
 	if (ret)
 		return ret;
 	/* ensure that buffer size is a multiple of period size */
 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
 					    SNDRV_PCM_HW_PARAM_PERIODS);
 	if (ret < 0)
 		return ret;
 	substream->runtime->private_data = dmadata;
 	return 0;
 }

 static int txx9aclc_pcm_close(struct snd_pcm_substream *substream)
 {
 	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;
 	struct dma_chan *chan = dmadata->dma_chan;

 	dmadata->frag_count = -1;
 	chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
 	return 0;
 }

 static struct snd_pcm_ops txx9aclc_pcm_ops = {
 	.open		= txx9aclc_pcm_open,
 	.close		= txx9aclc_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,
 	.hw_params	= txx9aclc_pcm_hw_params,
 	.hw_free	= txx9aclc_pcm_hw_free,
 	.prepare	= txx9aclc_pcm_prepare,
 	.trigger	= txx9aclc_pcm_trigger,
 	.pointer	= txx9aclc_pcm_pointer,
 };

 static void txx9aclc_pcm_free_dma_buffers(struct snd_pcm *pcm)
 {
 	snd_pcm_lib_preallocate_free_for_all(pcm);
 }

 static int txx9aclc_pcm_new(struct snd_soc_pcm_runtime *rtd)
 {
 	struct snd_card *card = rtd->card->snd_card;
 	struct snd_soc_dai *dai = rtd->cpu_dai;
 	struct snd_pcm *pcm = rtd->pcm;
 	struct platform_device *pdev = to_platform_device(dai->platform->dev);
 	struct txx9aclc_soc_device *dev;
 	struct resource *r;
 	int i;
 	int ret;

 	/* at this point onwards the AC97 component has probed and this will be valid */
 	dev = snd_soc_dai_get_drvdata(dai);

 	dev->dmadata[0].stream = SNDRV_PCM_STREAM_PLAYBACK;
 	dev->dmadata[1].stream = SNDRV_PCM_STREAM_CAPTURE;
 	for (i = 0; i < 2; i++) {
 		r = platform_get_resource(pdev, IORESOURCE_DMA, i);
 		if (!r) {
 			ret = -EBUSY;
 			goto exit;
 		}
 		dev->dmadata[i].dma_res = r;
 		ret = txx9aclc_dma_init(dev, &dev->dmadata[i]);
 		if (ret)
 			goto exit;
 	}
 	return snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
 		card->dev, 64 * 1024, 4 * 1024 * 1024);

 exit:
 	for (i = 0; i < 2; i++) {
 		if (dev->dmadata[i].dma_chan)
 			dma_release_channel(dev->dmadata[i].dma_chan);
 		dev->dmadata[i].dma_chan = NULL;
 	}
 	return ret;
 }

 static bool filter(struct dma_chan *chan, void *param)
 {
 	struct txx9aclc_dmadata *dmadata = param;
 	char *devname;
 	bool found = false;

 	devname = kasprintf(GFP_KERNEL, "%s.%d", dmadata->dma_res->name,
 		(int)dmadata->dma_res->start);
 	if (strcmp(dev_name(chan->device->dev), devname) == 0) {
 		chan->private = &dmadata->dma_slave;
 		found = true;
 	}
 	kfree(devname);
 	return found;
 }

 static int txx9aclc_dma_init(struct txx9aclc_soc_device *dev,
 			     struct txx9aclc_dmadata *dmadata)
 {
 	struct txx9aclc_plat_drvdata *drvdata =txx9aclc_drvdata;
 	struct txx9dmac_slave *ds = &dmadata->dma_slave;
 	dma_cap_mask_t mask;

 	spin_lock_init(&dmadata->dma_lock);

 	ds->reg_width = sizeof(u32);
 	if (dmadata->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 		ds->tx_reg = drvdata->physbase + ACAUDODAT;
 		ds->rx_reg = 0;
 	} else {
 		ds->tx_reg = 0;
 		ds->rx_reg = drvdata->physbase + ACAUDIDAT;
 	}

 	/* Try to grab a DMA channel */
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 	dmadata->dma_chan = dma_request_channel(mask, filter, dmadata);
 	if (!dmadata->dma_chan) {
 		printk(KERN_ERR
 			"DMA channel for %s is not available\n",
 			dmadata->stream == SNDRV_PCM_STREAM_PLAYBACK ?
 			"playback" : "capture");
 		return -EBUSY;
 	}
 	tasklet_init(&dmadata->tasklet, txx9aclc_dma_tasklet,
 		     (unsigned long)dmadata);
 	return 0;
 }

 static int txx9aclc_pcm_probe(struct snd_soc_platform *platform)
 {
 	snd_soc_platform_set_drvdata(platform, &txx9aclc_soc_device);
 	return 0;
 }

 static int txx9aclc_pcm_remove(struct snd_soc_platform *platform)
 {
 	struct txx9aclc_soc_device *dev = snd_soc_platform_get_drvdata(platform);
 	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
 	void __iomem *base = drvdata->base;
 	int i;

 	/* disable all FIFO DMAs */
 	__raw_writel(ACCTL_AUDODMA | ACCTL_AUDIDMA, base + ACCTLDIS);
 	/* dummy R/W to clear pending DMAREQ if any */
 	__raw_writel(__raw_readl(base + ACAUDIDAT), base + ACAUDODAT);

 	for (i = 0; i < 2; i++) {
 		struct txx9aclc_dmadata *dmadata = &dev->dmadata[i];
 		struct dma_chan *chan = dmadata->dma_chan;
 		if (chan) {
 			dmadata->frag_count = -1;
 			chan->device->device_control(chan,
 						     DMA_TERMINATE_ALL, 0);
 			dma_release_channel(chan);
 		}
 		dev->dmadata[i].dma_chan = NULL;
 	}
 	return 0;
 }

 static struct snd_soc_platform_driver txx9aclc_soc_platform = {
 	.probe		= txx9aclc_pcm_probe,
 	.remove		= txx9aclc_pcm_remove,
 	.ops		= &txx9aclc_pcm_ops,
 	.pcm_new	= txx9aclc_pcm_new,
 	.pcm_free	= txx9aclc_pcm_free_dma_buffers,
 };

 static int __devinit txx9aclc_soc_platform_probe(struct platform_device *pdev)
 {
 	return snd_soc_register_platform(&pdev->dev, &txx9aclc_soc_platform);
 }

 static int __devexit txx9aclc_soc_platform_remove(struct platform_device *pdev)
 {
 	snd_soc_unregister_platform(&pdev->dev);
 	return 0;
 }

 static struct platform_driver txx9aclc_pcm_driver = {
 	.driver = {
 			.name = "txx9aclc-pcm-audio",
 			.owner = THIS_MODULE,
 	},

 	.probe = txx9aclc_soc_platform_probe,
 	.remove = __devexit_p(txx9aclc_soc_platform_remove),
 };

 static int __init snd_txx9aclc_pcm_init(void)
 {
 	return platform_driver_register(&txx9aclc_pcm_driver);
 }
 module_init(snd_txx9aclc_pcm_init);

 static void __exit snd_txx9aclc_pcm_exit(void)
 {
 	platform_driver_unregister(&txx9aclc_pcm_driver);
 }
 module_exit(snd_txx9aclc_pcm_exit);

 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
 MODULE_DESCRIPTION("TXx9 ACLC Audio DMA driver");
 MODULE_LICENSE("GPL");
	/*
	* Generic TXx9 ACLC platform driver
	*
	* Copyright (C) 2009 Atsushi Nemoto
	*
	* Based on RBTX49xx patch from CELF patch archive.
	* (C) Copyright TOSHIBA CORPORATION 2004-2006
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/scatterlist.h>
	#include <linux/slab.h>
	#include <sound/core.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/soc.h>
	#include "txx9aclc.h"

	static struct txx9aclc_soc_device {
	struct txx9aclc_dmadata dmadata[2];
	} txx9aclc_soc_device;

	/* REVISIT: How to find txx9aclc_drvdata from snd_ac97? */
	static struct txx9aclc_plat_drvdata *txx9aclc_drvdata;

	static int txx9aclc_dma_init(struct txx9aclc_soc_device *dev,
	struct txx9aclc_dmadata *dmadata);

	static const struct snd_pcm_hardware txx9aclc_pcm_hardware = {
	/*
	* REVISIT: SNDRV_PCM_INFO_MMAP \| SNDRV_PCM_INFO_MMAP_VALID
	* needs more works for noncoherent MIPS.
	*/
	.info = SNDRV_PCM_INFO_INTERLEAVED \|
	SNDRV_PCM_INFO_BATCH \|
	SNDRV_PCM_INFO_PAUSE,
	#ifdef __BIG_ENDIAN
	.formats = SNDRV_PCM_FMTBIT_S16_BE,
	#else
	.formats = SNDRV_PCM_FMTBIT_S16_LE,
	#endif
	.period_bytes_min = 1024,
	.period_bytes_max = 8 * 1024,
	.periods_min = 2,
	.periods_max = 4096,
	.buffer_bytes_max = 32 * 1024,
	};

	static int txx9aclc_pcm_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params)
	{
	struct snd_soc_pcm_runtime *rtd = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct txx9aclc_dmadata *dmadata = runtime->private_data;
	int ret;

	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
	if (ret < 0)
	return ret;

	dev_dbg(rtd->platform->dev,
	"runtime->dma_area = %#lx dma_addr = %#lx dma_bytes = %zd "
	"runtime->min_align %ld\n",
	(unsigned long)runtime->dma_area,
	(unsigned long)runtime->dma_addr, runtime->dma_bytes,
	runtime->min_align);
	dev_dbg(rtd->platform->dev,
	"periods %d period_bytes %d stream %d\n",
	params_periods(params), params_period_bytes(params),
	substream->stream);

	dmadata->substream = substream;
	dmadata->pos = 0;
	return 0;
	}

	static int txx9aclc_pcm_hw_free(struct snd_pcm_substream *substream)
	{
	return snd_pcm_lib_free_pages(substream);
	}

	static int txx9aclc_pcm_prepare(struct snd_pcm_substream *substream)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct txx9aclc_dmadata *dmadata = runtime->private_data;

	dmadata->dma_addr = runtime->dma_addr;
	dmadata->buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
	dmadata->period_bytes = snd_pcm_lib_period_bytes(substream);

	if (dmadata->buffer_bytes == dmadata->period_bytes) {
	dmadata->frag_bytes = dmadata->period_bytes >> 1;
	dmadata->frags = 2;
	} else {
	dmadata->frag_bytes = dmadata->period_bytes;
	dmadata->frags = dmadata->buffer_bytes / dmadata->period_bytes;
	}
	dmadata->frag_count = 0;
	dmadata->pos = 0;
	return 0;
	}

	static void txx9aclc_dma_complete(void *arg)
	{
	struct txx9aclc_dmadata *dmadata = arg;
	unsigned long flags;

	/* dma completion handler cannot submit new operations */
	spin_lock_irqsave(&dmadata->dma_lock, flags);
	if (dmadata->frag_count >= 0) {
	dmadata->dmacount--;
	BUG_ON(dmadata->dmacount < 0);
	tasklet_schedule(&dmadata->tasklet);
	}
	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	}

	static struct dma_async_tx_descriptor *
	txx9aclc_dma_submit(struct txx9aclc_dmadata *dmadata, dma_addr_t buf_dma_addr)
	{
	struct dma_chan *chan = dmadata->dma_chan;
	struct dma_async_tx_descriptor *desc;
	struct scatterlist sg;

	sg_init_table(&sg, 1);
	sg_set_page(&sg, pfn_to_page(PFN_DOWN(buf_dma_addr)),
	dmadata->frag_bytes, buf_dma_addr & (PAGE_SIZE - 1));
	sg_dma_address(&sg) = buf_dma_addr;
	desc = chan->device->device_prep_slave_sg(chan, &sg, 1,
	dmadata->substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
	DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
	DMA_PREP_INTERRUPT \| DMA_CTRL_ACK);
	if (!desc) {
	dev_err(&chan->dev->device, "cannot prepare slave dma\n");
	return NULL;
	}
	desc->callback = txx9aclc_dma_complete;
	desc->callback_param = dmadata;
	desc->tx_submit(desc);
	return desc;
	}

	#define NR_DMA_CHAIN 2

	static void txx9aclc_dma_tasklet(unsigned long data)
	{
	struct txx9aclc_dmadata dmadata = (struct txx9aclc_dmadata )data;
	struct dma_chan *chan = dmadata->dma_chan;
	struct dma_async_tx_descriptor *desc;
	struct snd_pcm_substream *substream = dmadata->substream;
	u32 ctlbit = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
	ACCTL_AUDODMA : ACCTL_AUDIDMA;
	int i;
	unsigned long flags;

	spin_lock_irqsave(&dmadata->dma_lock, flags);
	if (dmadata->frag_count < 0) {
	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
	void __iomem *base = drvdata->base;

	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
	/* first time */
	for (i = 0; i < NR_DMA_CHAIN; i++) {
	desc = txx9aclc_dma_submit(dmadata,
	dmadata->dma_addr + i * dmadata->frag_bytes);
	if (!desc)
	return;
	}
	dmadata->dmacount = NR_DMA_CHAIN;
	chan->device->device_issue_pending(chan);
	spin_lock_irqsave(&dmadata->dma_lock, flags);
	__raw_writel(ctlbit, base + ACCTLEN);
	dmadata->frag_count = NR_DMA_CHAIN % dmadata->frags;
	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	return;
	}
	BUG_ON(dmadata->dmacount >= NR_DMA_CHAIN);
	while (dmadata->dmacount < NR_DMA_CHAIN) {
	dmadata->dmacount++;
	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	desc = txx9aclc_dma_submit(dmadata,
	dmadata->dma_addr +
	dmadata->frag_count * dmadata->frag_bytes);
	if (!desc)
	return;
	chan->device->device_issue_pending(chan);

	spin_lock_irqsave(&dmadata->dma_lock, flags);
	dmadata->frag_count++;
	dmadata->frag_count %= dmadata->frags;
	dmadata->pos += dmadata->frag_bytes;
	dmadata->pos %= dmadata->buffer_bytes;
	if ((dmadata->frag_count * dmadata->frag_bytes) %
	dmadata->period_bytes == 0)
	snd_pcm_period_elapsed(substream);
	}
	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	}

	static int txx9aclc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
	{
	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;
	struct txx9aclc_plat_drvdata *drvdata =txx9aclc_drvdata;
	void __iomem *base = drvdata->base;
	unsigned long flags;
	int ret = 0;
	u32 ctlbit = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
	ACCTL_AUDODMA : ACCTL_AUDIDMA;

	spin_lock_irqsave(&dmadata->dma_lock, flags);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	dmadata->frag_count = -1;
	tasklet_schedule(&dmadata->tasklet);
	break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	__raw_writel(ctlbit, base + ACCTLDIS);
	break;
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	case SNDRV_PCM_TRIGGER_RESUME:
	__raw_writel(ctlbit, base + ACCTLEN);
	break;
	default:
	ret = -EINVAL;
	}
	spin_unlock_irqrestore(&dmadata->dma_lock, flags);
	return ret;
	}

	static snd_pcm_uframes_t
	txx9aclc_pcm_pointer(struct snd_pcm_substream *substream)
	{
	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;

	return bytes_to_frames(substream->runtime, dmadata->pos);
	}

	static int txx9aclc_pcm_open(struct snd_pcm_substream *substream)
	{
	struct txx9aclc_soc_device *dev = &txx9aclc_soc_device;
	struct txx9aclc_dmadata *dmadata = &dev->dmadata[substream->stream];
	int ret;

	ret = snd_soc_set_runtime_hwparams(substream, &txx9aclc_pcm_hardware);
	if (ret)
	return ret;
	/* ensure that buffer size is a multiple of period size */
	ret = snd_pcm_hw_constraint_integer(substream->runtime,
	SNDRV_PCM_HW_PARAM_PERIODS);
	if (ret < 0)
	return ret;
	substream->runtime->private_data = dmadata;
	return 0;
	}

	static int txx9aclc_pcm_close(struct snd_pcm_substream *substream)
	{
	struct txx9aclc_dmadata *dmadata = substream->runtime->private_data;
	struct dma_chan *chan = dmadata->dma_chan;

	dmadata->frag_count = -1;
	chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
	return 0;
	}

	static struct snd_pcm_ops txx9aclc_pcm_ops = {
	.open = txx9aclc_pcm_open,
	.close = txx9aclc_pcm_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = txx9aclc_pcm_hw_params,
	.hw_free = txx9aclc_pcm_hw_free,
	.prepare = txx9aclc_pcm_prepare,
	.trigger = txx9aclc_pcm_trigger,
	.pointer = txx9aclc_pcm_pointer,
	};

	static void txx9aclc_pcm_free_dma_buffers(struct snd_pcm *pcm)
	{
	snd_pcm_lib_preallocate_free_for_all(pcm);
	}

	static int txx9aclc_pcm_new(struct snd_soc_pcm_runtime *rtd)
	{
	struct snd_card *card = rtd->card->snd_card;
	struct snd_soc_dai *dai = rtd->cpu_dai;
	struct snd_pcm *pcm = rtd->pcm;
	struct platform_device *pdev = to_platform_device(dai->platform->dev);
	struct txx9aclc_soc_device *dev;
	struct resource *r;
	int i;
	int ret;

	/* at this point onwards the AC97 component has probed and this will be valid */
	dev = snd_soc_dai_get_drvdata(dai);

	dev->dmadata[0].stream = SNDRV_PCM_STREAM_PLAYBACK;
	dev->dmadata[1].stream = SNDRV_PCM_STREAM_CAPTURE;
	for (i = 0; i < 2; i++) {
	r = platform_get_resource(pdev, IORESOURCE_DMA, i);
	if (!r) {
	ret = -EBUSY;
	goto exit;
	}
	dev->dmadata[i].dma_res = r;
	ret = txx9aclc_dma_init(dev, &dev->dmadata[i]);
	if (ret)
	goto exit;
	}
	return snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
	card->dev, 64 * 1024, 4 * 1024 * 1024);

	exit:
	for (i = 0; i < 2; i++) {
	if (dev->dmadata[i].dma_chan)
	dma_release_channel(dev->dmadata[i].dma_chan);
	dev->dmadata[i].dma_chan = NULL;
	}
	return ret;
	}

	static bool filter(struct dma_chan chan, void param)
	{
	struct txx9aclc_dmadata *dmadata = param;
	char *devname;
	bool found = false;

	devname = kasprintf(GFP_KERNEL, "%s.%d", dmadata->dma_res->name,
	(int)dmadata->dma_res->start);
	if (strcmp(dev_name(chan->device->dev), devname) == 0) {
	chan->private = &dmadata->dma_slave;
	found = true;
	}
	kfree(devname);
	return found;
	}

	static int txx9aclc_dma_init(struct txx9aclc_soc_device *dev,
	struct txx9aclc_dmadata *dmadata)
	{
	struct txx9aclc_plat_drvdata *drvdata =txx9aclc_drvdata;
	struct txx9dmac_slave *ds = &dmadata->dma_slave;
	dma_cap_mask_t mask;

	spin_lock_init(&dmadata->dma_lock);

	ds->reg_width = sizeof(u32);
	if (dmadata->stream == SNDRV_PCM_STREAM_PLAYBACK) {
	ds->tx_reg = drvdata->physbase + ACAUDODAT;
	ds->rx_reg = 0;
	} else {
	ds->tx_reg = 0;
	ds->rx_reg = drvdata->physbase + ACAUDIDAT;
	}

	/* Try to grab a DMA channel */
	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);
	dmadata->dma_chan = dma_request_channel(mask, filter, dmadata);
	if (!dmadata->dma_chan) {
	printk(KERN_ERR
	"DMA channel for %s is not available\n",
	dmadata->stream == SNDRV_PCM_STREAM_PLAYBACK ?
	"playback" : "capture");
	return -EBUSY;
	}
	tasklet_init(&dmadata->tasklet, txx9aclc_dma_tasklet,
	(unsigned long)dmadata);
	return 0;
	}

	static int txx9aclc_pcm_probe(struct snd_soc_platform *platform)
	{
	snd_soc_platform_set_drvdata(platform, &txx9aclc_soc_device);
	return 0;
	}

	static int txx9aclc_pcm_remove(struct snd_soc_platform *platform)
	{
	struct txx9aclc_soc_device *dev = snd_soc_platform_get_drvdata(platform);
	struct txx9aclc_plat_drvdata *drvdata = txx9aclc_drvdata;
	void __iomem *base = drvdata->base;
	int i;

	/* disable all FIFO DMAs */
	__raw_writel(ACCTL_AUDODMA \| ACCTL_AUDIDMA, base + ACCTLDIS);
	/* dummy R/W to clear pending DMAREQ if any */
	__raw_writel(__raw_readl(base + ACAUDIDAT), base + ACAUDODAT);

	for (i = 0; i < 2; i++) {
	struct txx9aclc_dmadata *dmadata = &dev->dmadata[i];
	struct dma_chan *chan = dmadata->dma_chan;
	if (chan) {
	dmadata->frag_count = -1;
	chan->device->device_control(chan,
	DMA_TERMINATE_ALL, 0);
	dma_release_channel(chan);
	}
	dev->dmadata[i].dma_chan = NULL;
	}
	return 0;
	}

	static struct snd_soc_platform_driver txx9aclc_soc_platform = {
	.probe = txx9aclc_pcm_probe,
	.remove = txx9aclc_pcm_remove,
	.ops = &txx9aclc_pcm_ops,
	.pcm_new = txx9aclc_pcm_new,
	.pcm_free = txx9aclc_pcm_free_dma_buffers,
	};

	static int __devinit txx9aclc_soc_platform_probe(struct platform_device *pdev)
	{
	return snd_soc_register_platform(&pdev->dev, &txx9aclc_soc_platform);
	}

	static int __devexit txx9aclc_soc_platform_remove(struct platform_device *pdev)
	{
	snd_soc_unregister_platform(&pdev->dev);
	return 0;
	}

	static struct platform_driver txx9aclc_pcm_driver = {
	.driver = {
	.name = "txx9aclc-pcm-audio",
	.owner = THIS_MODULE,
	},

	.probe = txx9aclc_soc_platform_probe,
	.remove = __devexit_p(txx9aclc_soc_platform_remove),
	};

	static int __init snd_txx9aclc_pcm_init(void)
	{
	return platform_driver_register(&txx9aclc_pcm_driver);
	}
	module_init(snd_txx9aclc_pcm_init);

	static void __exit snd_txx9aclc_pcm_exit(void)
	{
	platform_driver_unregister(&txx9aclc_pcm_driver);
	}
	module_exit(snd_txx9aclc_pcm_exit);

	MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
	MODULE_DESCRIPTION("TXx9 ACLC Audio DMA driver");
	MODULE_LICENSE("GPL");