sound/pci/cs5535audio/cs5535audio_pcm.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Driver for audio on multifunction CS5535 companion device
  * Copyright (C) Jaya Kumar
  *
  * Based on Jaroslav Kysela and Takashi Iwai's examples.
  * This work was sponsored by CIS(M) Sdn Bhd.
  *
  * todo: add be fmt support, spdif, pm
  */

 #include <linux/init.h>
 #include <linux/pci.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/initval.h>
 #include <sound/asoundef.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/ac97_codec.h>
 #include "cs5535audio.h"

 static const struct snd_pcm_hardware snd_cs5535audio_playback =
 {
 	.info =			(
 				SNDRV_PCM_INFO_MMAP |
 				SNDRV_PCM_INFO_INTERLEAVED |
 		 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
 		 		SNDRV_PCM_INFO_MMAP_VALID |
 		 		SNDRV_PCM_INFO_PAUSE |
 				SNDRV_PCM_INFO_RESUME
 				),
 	.formats =		(
 				SNDRV_PCM_FMTBIT_S16_LE
 				),
 	.rates =		(
 				SNDRV_PCM_RATE_CONTINUOUS |
 				SNDRV_PCM_RATE_8000_48000
 				),
 	.rate_min =		4000,
 	.rate_max =		48000,
 	.channels_min =		2,
 	.channels_max =		2,
 	.buffer_bytes_max =	(128*1024),
 	.period_bytes_min =	64,
 	.period_bytes_max =	(64*1024 - 16),
 	.periods_min =		1,
 	.periods_max =		CS5535AUDIO_MAX_DESCRIPTORS,
 	.fifo_size =		0,
 };

 static const struct snd_pcm_hardware snd_cs5535audio_capture =
 {
 	.info =			(
 				SNDRV_PCM_INFO_MMAP |
 				SNDRV_PCM_INFO_INTERLEAVED |
 		 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
 		 		SNDRV_PCM_INFO_MMAP_VALID
 				),
 	.formats =		(
 				SNDRV_PCM_FMTBIT_S16_LE
 				),
 	.rates =		(
 				SNDRV_PCM_RATE_CONTINUOUS |
 				SNDRV_PCM_RATE_8000_48000
 				),
 	.rate_min =		4000,
 	.rate_max =		48000,
 	.channels_min =		2,
 	.channels_max =		2,
 	.buffer_bytes_max =	(128*1024),
 	.period_bytes_min =	64,
 	.period_bytes_max =	(64*1024 - 16),
 	.periods_min =		1,
 	.periods_max =		CS5535AUDIO_MAX_DESCRIPTORS,
 	.fifo_size =		0,
 };

 static int snd_cs5535audio_playback_open(struct snd_pcm_substream *substream)
 {
 	int err;
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	struct snd_pcm_runtime *runtime = substream->runtime;

 	runtime->hw = snd_cs5535audio_playback;
 	runtime->hw.rates = cs5535au->ac97->rates[AC97_RATES_FRONT_DAC];
 	snd_pcm_limit_hw_rates(runtime);
 	cs5535au->playback_substream = substream;
 	runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK]);
 	if ((err = snd_pcm_hw_constraint_integer(runtime,
 				SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
 		return err;

 	return 0;
 }

 static int snd_cs5535audio_playback_close(struct snd_pcm_substream *substream)
 {
 	return 0;
 }

 #define CS5535AUDIO_DESC_LIST_SIZE \
 	PAGE_ALIGN(CS5535AUDIO_MAX_DESCRIPTORS * sizeof(struct cs5535audio_dma_desc))

 static int cs5535audio_build_dma_packets(struct cs5535audio *cs5535au,
 					 struct cs5535audio_dma *dma,
 					 struct snd_pcm_substream *substream,
 					 unsigned int periods,
 					 unsigned int period_bytes)
 {
 	unsigned int i;
 	u32 addr, desc_addr, jmpprd_addr;
 	struct cs5535audio_dma_desc *lastdesc;

 	if (periods > CS5535AUDIO_MAX_DESCRIPTORS)
 		return -ENOMEM;

 	if (dma->desc_buf.area == NULL) {
 		if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
 					&cs5535au->pci->dev,
 					CS5535AUDIO_DESC_LIST_SIZE+1,
 					&dma->desc_buf) < 0)
 			return -ENOMEM;
 		dma->period_bytes = dma->periods = 0;
 	}

 	if (dma->periods == periods && dma->period_bytes == period_bytes)
 		return 0;

 	/* the u32 cast is okay because in snd*create we successfully told
    	   pci alloc that we're only 32 bit capable so the uppper will be 0 */
 	addr = (u32) substream->runtime->dma_addr;
 	desc_addr = (u32) dma->desc_buf.addr;
 	for (i = 0; i < periods; i++) {
 		struct cs5535audio_dma_desc *desc =
 			&((struct cs5535audio_dma_desc *) dma->desc_buf.area)[i];
 		desc->addr = cpu_to_le32(addr);
 		desc->size = cpu_to_le16(period_bytes);
 		desc->ctlreserved = cpu_to_le16(PRD_EOP);
 		desc_addr += sizeof(struct cs5535audio_dma_desc);
 		addr += period_bytes;
 	}
 	/* we reserved one dummy descriptor at the end to do the PRD jump */
 	lastdesc = &((struct cs5535audio_dma_desc *) dma->desc_buf.area)[periods];
 	lastdesc->addr = cpu_to_le32((u32) dma->desc_buf.addr);
 	lastdesc->size = 0;
 	lastdesc->ctlreserved = cpu_to_le16(PRD_JMP);
 	jmpprd_addr = (u32)dma->desc_buf.addr +
 		sizeof(struct cs5535audio_dma_desc) * periods;

 	dma->substream = substream;
 	dma->period_bytes = period_bytes;
 	dma->periods = periods;
 	spin_lock_irq(&cs5535au->reg_lock);
 	dma->ops->disable_dma(cs5535au);
 	dma->ops->setup_prd(cs5535au, jmpprd_addr);
 	spin_unlock_irq(&cs5535au->reg_lock);
 	return 0;
 }

 static void cs5535audio_playback_enable_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_EN);
 }

 static void cs5535audio_playback_disable_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM0_CMD, 0);
 }

 static void cs5535audio_playback_pause_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_PAUSE);
 }

 static void cs5535audio_playback_setup_prd(struct cs5535audio *cs5535au,
 					   u32 prd_addr)
 {
 	cs_writel(cs5535au, ACC_BM0_PRD, prd_addr);
 }

 static u32 cs5535audio_playback_read_prd(struct cs5535audio *cs5535au)
 {
 	return cs_readl(cs5535au, ACC_BM0_PRD);
 }

 static u32 cs5535audio_playback_read_dma_pntr(struct cs5535audio *cs5535au)
 {
 	return cs_readl(cs5535au, ACC_BM0_PNTR);
 }

 static void cs5535audio_capture_enable_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_EN);
 }

 static void cs5535audio_capture_disable_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM1_CMD, 0);
 }

 static void cs5535audio_capture_pause_dma(struct cs5535audio *cs5535au)
 {
 	cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_PAUSE);
 }

 static void cs5535audio_capture_setup_prd(struct cs5535audio *cs5535au,
 					  u32 prd_addr)
 {
 	cs_writel(cs5535au, ACC_BM1_PRD, prd_addr);
 }

 static u32 cs5535audio_capture_read_prd(struct cs5535audio *cs5535au)
 {
 	return cs_readl(cs5535au, ACC_BM1_PRD);
 }

 static u32 cs5535audio_capture_read_dma_pntr(struct cs5535audio *cs5535au)
 {
 	return cs_readl(cs5535au, ACC_BM1_PNTR);
 }

 static void cs5535audio_clear_dma_packets(struct cs5535audio *cs5535au,
 					  struct cs5535audio_dma *dma,
 					  struct snd_pcm_substream *substream)
 {
 	snd_dma_free_pages(&dma->desc_buf);
 	dma->desc_buf.area = NULL;
 	dma->substream = NULL;
 }

 static int snd_cs5535audio_hw_params(struct snd_pcm_substream *substream,
 				     struct snd_pcm_hw_params *hw_params)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	struct cs5535audio_dma *dma = substream->runtime->private_data;
 	int err;

 	dma->buf_addr = substream->runtime->dma_addr;
 	dma->buf_bytes = params_buffer_bytes(hw_params);

 	err = cs5535audio_build_dma_packets(cs5535au, dma, substream,
 					    params_periods(hw_params),
 					    params_period_bytes(hw_params));
 	if (!err)
 		dma->pcm_open_flag = 1;

 	return err;
 }

 static int snd_cs5535audio_hw_free(struct snd_pcm_substream *substream)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	struct cs5535audio_dma *dma = substream->runtime->private_data;

 	if (dma->pcm_open_flag) {
 		if (substream == cs5535au->playback_substream)
 			snd_ac97_update_power(cs5535au->ac97,
 					AC97_PCM_FRONT_DAC_RATE, 0);
 		else
 			snd_ac97_update_power(cs5535au->ac97,
 					AC97_PCM_LR_ADC_RATE, 0);
 		dma->pcm_open_flag = 0;
 	}
 	cs5535audio_clear_dma_packets(cs5535au, dma, substream);
 	return 0;
 }

 static int snd_cs5535audio_playback_prepare(struct snd_pcm_substream *substream)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_FRONT_DAC_RATE,
 				 substream->runtime->rate);
 }

 static int snd_cs5535audio_trigger(struct snd_pcm_substream *substream, int cmd)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	struct cs5535audio_dma *dma = substream->runtime->private_data;
 	int err = 0;

 	spin_lock(&cs5535au->reg_lock);
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 		dma->ops->pause_dma(cs5535au);
 		break;
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 		dma->ops->enable_dma(cs5535au);
 		break;
 	case SNDRV_PCM_TRIGGER_START:
 		dma->ops->enable_dma(cs5535au);
 		break;
 	case SNDRV_PCM_TRIGGER_RESUME:
 		dma->ops->enable_dma(cs5535au);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 		dma->ops->disable_dma(cs5535au);
 		break;
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 		dma->ops->disable_dma(cs5535au);
 		break;
 	default:
 		dev_err(cs5535au->card->dev, "unhandled trigger\n");
 		err = -EINVAL;
 		break;
 	}
 	spin_unlock(&cs5535au->reg_lock);
 	return err;
 }

 static snd_pcm_uframes_t snd_cs5535audio_pcm_pointer(struct snd_pcm_substream
 							*substream)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	u32 curdma;
 	struct cs5535audio_dma *dma;

 	dma = substream->runtime->private_data;
 	curdma = dma->ops->read_dma_pntr(cs5535au);
 	if (curdma < dma->buf_addr) {
 		dev_err(cs5535au->card->dev, "curdma=%x < %x bufaddr.\n",
 					curdma, dma->buf_addr);
 		return 0;
 	}
 	curdma -= dma->buf_addr;
 	if (curdma >= dma->buf_bytes) {
 		dev_err(cs5535au->card->dev, "diff=%x >= %x buf_bytes.\n",
 					curdma, dma->buf_bytes);
 		return 0;
 	}
 	return bytes_to_frames(substream->runtime, curdma);
 }

 static int snd_cs5535audio_capture_open(struct snd_pcm_substream *substream)
 {
 	int err;
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	struct snd_pcm_runtime *runtime = substream->runtime;

 	runtime->hw = snd_cs5535audio_capture;
 	runtime->hw.rates = cs5535au->ac97->rates[AC97_RATES_ADC];
 	snd_pcm_limit_hw_rates(runtime);
 	cs5535au->capture_substream = substream;
 	runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE]);
 	if ((err = snd_pcm_hw_constraint_integer(runtime,
 					 SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
 		return err;
 	olpc_capture_open(cs5535au->ac97);
 	return 0;
 }

 static int snd_cs5535audio_capture_close(struct snd_pcm_substream *substream)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	olpc_capture_close(cs5535au->ac97);
 	return 0;
 }

 static int snd_cs5535audio_capture_prepare(struct snd_pcm_substream *substream)
 {
 	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
 	return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_LR_ADC_RATE,
 				 substream->runtime->rate);
 }

 static const struct snd_pcm_ops snd_cs5535audio_playback_ops = {
 	.open =		snd_cs5535audio_playback_open,
 	.close =	snd_cs5535audio_playback_close,
 	.hw_params =	snd_cs5535audio_hw_params,
 	.hw_free =	snd_cs5535audio_hw_free,
 	.prepare =	snd_cs5535audio_playback_prepare,
 	.trigger =	snd_cs5535audio_trigger,
 	.pointer =	snd_cs5535audio_pcm_pointer,
 };

 static const struct snd_pcm_ops snd_cs5535audio_capture_ops = {
 	.open =		snd_cs5535audio_capture_open,
 	.close =	snd_cs5535audio_capture_close,
 	.hw_params =	snd_cs5535audio_hw_params,
 	.hw_free =	snd_cs5535audio_hw_free,
 	.prepare =	snd_cs5535audio_capture_prepare,
 	.trigger =	snd_cs5535audio_trigger,
 	.pointer =	snd_cs5535audio_pcm_pointer,
 };

 static const struct cs5535audio_dma_ops snd_cs5535audio_playback_dma_ops = {
         .type = CS5535AUDIO_DMA_PLAYBACK,
         .enable_dma = cs5535audio_playback_enable_dma,
         .disable_dma = cs5535audio_playback_disable_dma,
         .setup_prd = cs5535audio_playback_setup_prd,
         .read_prd = cs5535audio_playback_read_prd,
         .pause_dma = cs5535audio_playback_pause_dma,
         .read_dma_pntr = cs5535audio_playback_read_dma_pntr,
 };

 static const struct cs5535audio_dma_ops snd_cs5535audio_capture_dma_ops = {
         .type = CS5535AUDIO_DMA_CAPTURE,
         .enable_dma = cs5535audio_capture_enable_dma,
         .disable_dma = cs5535audio_capture_disable_dma,
         .setup_prd = cs5535audio_capture_setup_prd,
         .read_prd = cs5535audio_capture_read_prd,
         .pause_dma = cs5535audio_capture_pause_dma,
         .read_dma_pntr = cs5535audio_capture_read_dma_pntr,
 };

 int snd_cs5535audio_pcm(struct cs5535audio *cs5535au)
 {
 	struct snd_pcm *pcm;
 	int err;

 	err = snd_pcm_new(cs5535au->card, "CS5535 Audio", 0, 1, 1, &pcm);
 	if (err < 0)
 		return err;

 	cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK].ops =
 					&snd_cs5535audio_playback_dma_ops;
 	cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE].ops =
 					&snd_cs5535audio_capture_dma_ops;
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
 					&snd_cs5535audio_playback_ops);
 	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
 					&snd_cs5535audio_capture_ops);

 	pcm->private_data = cs5535au;
 	pcm->info_flags = 0;
 	strcpy(pcm->name, "CS5535 Audio");

 	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
 				       &cs5535au->pci->dev,
 				       64*1024, 128*1024);
 	cs5535au->pcm = pcm;

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Driver for audio on multifunction CS5535 companion device
	* Copyright (C) Jaya Kumar
	*
	* Based on Jaroslav Kysela and Takashi Iwai's examples.
	* This work was sponsored by CIS(M) Sdn Bhd.
	*
	* todo: add be fmt support, spdif, pm
	*/

	#include <linux/init.h>
	#include <linux/pci.h>
	#include <sound/core.h>
	#include <sound/control.h>
	#include <sound/initval.h>
	#include <sound/asoundef.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/ac97_codec.h>
	#include "cs5535audio.h"

	static const struct snd_pcm_hardware snd_cs5535audio_playback =
	{
	.info = (
	SNDRV_PCM_INFO_MMAP \|
	SNDRV_PCM_INFO_INTERLEAVED \|
	SNDRV_PCM_INFO_BLOCK_TRANSFER \|
	SNDRV_PCM_INFO_MMAP_VALID \|
	SNDRV_PCM_INFO_PAUSE \|
	SNDRV_PCM_INFO_RESUME
	),
	.formats = (
	SNDRV_PCM_FMTBIT_S16_LE
	),
	.rates = (
	SNDRV_PCM_RATE_CONTINUOUS \|
	SNDRV_PCM_RATE_8000_48000
	),
	.rate_min = 4000,
	.rate_max = 48000,
	.channels_min = 2,
	.channels_max = 2,
	.buffer_bytes_max = (128*1024),
	.period_bytes_min = 64,
	.period_bytes_max = (64*1024 - 16),
	.periods_min = 1,
	.periods_max = CS5535AUDIO_MAX_DESCRIPTORS,
	.fifo_size = 0,
	};

	static const struct snd_pcm_hardware snd_cs5535audio_capture =
	{
	.info = (
	SNDRV_PCM_INFO_MMAP \|
	SNDRV_PCM_INFO_INTERLEAVED \|
	SNDRV_PCM_INFO_BLOCK_TRANSFER \|
	SNDRV_PCM_INFO_MMAP_VALID
	),
	.formats = (
	SNDRV_PCM_FMTBIT_S16_LE
	),
	.rates = (
	SNDRV_PCM_RATE_CONTINUOUS \|
	SNDRV_PCM_RATE_8000_48000
	),
	.rate_min = 4000,
	.rate_max = 48000,
	.channels_min = 2,
	.channels_max = 2,
	.buffer_bytes_max = (128*1024),
	.period_bytes_min = 64,
	.period_bytes_max = (64*1024 - 16),
	.periods_min = 1,
	.periods_max = CS5535AUDIO_MAX_DESCRIPTORS,
	.fifo_size = 0,
	};

	static int snd_cs5535audio_playback_open(struct snd_pcm_substream *substream)
	{
	int err;
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;

	runtime->hw = snd_cs5535audio_playback;
	runtime->hw.rates = cs5535au->ac97->rates[AC97_RATES_FRONT_DAC];
	snd_pcm_limit_hw_rates(runtime);
	cs5535au->playback_substream = substream;
	runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK]);
	if ((err = snd_pcm_hw_constraint_integer(runtime,
	SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
	return err;

	return 0;
	}

	static int snd_cs5535audio_playback_close(struct snd_pcm_substream *substream)
	{
	return 0;
	}

	#define CS5535AUDIO_DESC_LIST_SIZE \
	PAGE_ALIGN(CS5535AUDIO_MAX_DESCRIPTORS * sizeof(struct cs5535audio_dma_desc))

	static int cs5535audio_build_dma_packets(struct cs5535audio *cs5535au,
	struct cs5535audio_dma *dma,
	struct snd_pcm_substream *substream,
	unsigned int periods,
	unsigned int period_bytes)
	{
	unsigned int i;
	u32 addr, desc_addr, jmpprd_addr;
	struct cs5535audio_dma_desc *lastdesc;

	if (periods > CS5535AUDIO_MAX_DESCRIPTORS)
	return -ENOMEM;

	if (dma->desc_buf.area == NULL) {
	if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
	&cs5535au->pci->dev,
	CS5535AUDIO_DESC_LIST_SIZE+1,
	&dma->desc_buf) < 0)
	return -ENOMEM;
	dma->period_bytes = dma->periods = 0;
	}

	if (dma->periods == periods && dma->period_bytes == period_bytes)
	return 0;

	/* the u32 cast is okay because in snd*create we successfully told
	pci alloc that we're only 32 bit capable so the uppper will be 0 */
	addr = (u32) substream->runtime->dma_addr;
	desc_addr = (u32) dma->desc_buf.addr;
	for (i = 0; i < periods; i++) {
	struct cs5535audio_dma_desc *desc =
	&((struct cs5535audio_dma_desc *) dma->desc_buf.area)[i];
	desc->addr = cpu_to_le32(addr);
	desc->size = cpu_to_le16(period_bytes);
	desc->ctlreserved = cpu_to_le16(PRD_EOP);
	desc_addr += sizeof(struct cs5535audio_dma_desc);
	addr += period_bytes;
	}
	/* we reserved one dummy descriptor at the end to do the PRD jump */
	lastdesc = &((struct cs5535audio_dma_desc *) dma->desc_buf.area)[periods];
	lastdesc->addr = cpu_to_le32((u32) dma->desc_buf.addr);
	lastdesc->size = 0;
	lastdesc->ctlreserved = cpu_to_le16(PRD_JMP);
	jmpprd_addr = (u32)dma->desc_buf.addr +
	sizeof(struct cs5535audio_dma_desc) * periods;

	dma->substream = substream;
	dma->period_bytes = period_bytes;
	dma->periods = periods;
	spin_lock_irq(&cs5535au->reg_lock);
	dma->ops->disable_dma(cs5535au);
	dma->ops->setup_prd(cs5535au, jmpprd_addr);
	spin_unlock_irq(&cs5535au->reg_lock);
	return 0;
	}

	static void cs5535audio_playback_enable_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_EN);
	}

	static void cs5535audio_playback_disable_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM0_CMD, 0);
	}

	static void cs5535audio_playback_pause_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_PAUSE);
	}

	static void cs5535audio_playback_setup_prd(struct cs5535audio *cs5535au,
	u32 prd_addr)
	{
	cs_writel(cs5535au, ACC_BM0_PRD, prd_addr);
	}

	static u32 cs5535audio_playback_read_prd(struct cs5535audio *cs5535au)
	{
	return cs_readl(cs5535au, ACC_BM0_PRD);
	}

	static u32 cs5535audio_playback_read_dma_pntr(struct cs5535audio *cs5535au)
	{
	return cs_readl(cs5535au, ACC_BM0_PNTR);
	}

	static void cs5535audio_capture_enable_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_EN);
	}

	static void cs5535audio_capture_disable_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM1_CMD, 0);
	}

	static void cs5535audio_capture_pause_dma(struct cs5535audio *cs5535au)
	{
	cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_PAUSE);
	}

	static void cs5535audio_capture_setup_prd(struct cs5535audio *cs5535au,
	u32 prd_addr)
	{
	cs_writel(cs5535au, ACC_BM1_PRD, prd_addr);
	}

	static u32 cs5535audio_capture_read_prd(struct cs5535audio *cs5535au)
	{
	return cs_readl(cs5535au, ACC_BM1_PRD);
	}

	static u32 cs5535audio_capture_read_dma_pntr(struct cs5535audio *cs5535au)
	{
	return cs_readl(cs5535au, ACC_BM1_PNTR);
	}

	static void cs5535audio_clear_dma_packets(struct cs5535audio *cs5535au,
	struct cs5535audio_dma *dma,
	struct snd_pcm_substream *substream)
	{
	snd_dma_free_pages(&dma->desc_buf);
	dma->desc_buf.area = NULL;
	dma->substream = NULL;
	}

	static int snd_cs5535audio_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *hw_params)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	struct cs5535audio_dma *dma = substream->runtime->private_data;
	int err;

	dma->buf_addr = substream->runtime->dma_addr;
	dma->buf_bytes = params_buffer_bytes(hw_params);

	err = cs5535audio_build_dma_packets(cs5535au, dma, substream,
	params_periods(hw_params),
	params_period_bytes(hw_params));
	if (!err)
	dma->pcm_open_flag = 1;

	return err;
	}

	static int snd_cs5535audio_hw_free(struct snd_pcm_substream *substream)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	struct cs5535audio_dma *dma = substream->runtime->private_data;

	if (dma->pcm_open_flag) {
	if (substream == cs5535au->playback_substream)
	snd_ac97_update_power(cs5535au->ac97,
	AC97_PCM_FRONT_DAC_RATE, 0);
	else
	snd_ac97_update_power(cs5535au->ac97,
	AC97_PCM_LR_ADC_RATE, 0);
	dma->pcm_open_flag = 0;
	}
	cs5535audio_clear_dma_packets(cs5535au, dma, substream);
	return 0;
	}

	static int snd_cs5535audio_playback_prepare(struct snd_pcm_substream *substream)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_FRONT_DAC_RATE,
	substream->runtime->rate);
	}

	static int snd_cs5535audio_trigger(struct snd_pcm_substream *substream, int cmd)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	struct cs5535audio_dma *dma = substream->runtime->private_data;
	int err = 0;

	spin_lock(&cs5535au->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
	dma->ops->pause_dma(cs5535au);
	break;
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
	dma->ops->enable_dma(cs5535au);
	break;
	case SNDRV_PCM_TRIGGER_START:
	dma->ops->enable_dma(cs5535au);
	break;
	case SNDRV_PCM_TRIGGER_RESUME:
	dma->ops->enable_dma(cs5535au);
	break;
	case SNDRV_PCM_TRIGGER_STOP:
	dma->ops->disable_dma(cs5535au);
	break;
	case SNDRV_PCM_TRIGGER_SUSPEND:
	dma->ops->disable_dma(cs5535au);
	break;
	default:
	dev_err(cs5535au->card->dev, "unhandled trigger\n");
	err = -EINVAL;
	break;
	}
	spin_unlock(&cs5535au->reg_lock);
	return err;
	}

	static snd_pcm_uframes_t snd_cs5535audio_pcm_pointer(struct snd_pcm_substream
	*substream)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	u32 curdma;
	struct cs5535audio_dma *dma;

	dma = substream->runtime->private_data;
	curdma = dma->ops->read_dma_pntr(cs5535au);
	if (curdma < dma->buf_addr) {
	dev_err(cs5535au->card->dev, "curdma=%x < %x bufaddr.\n",
	curdma, dma->buf_addr);
	return 0;
	}
	curdma -= dma->buf_addr;
	if (curdma >= dma->buf_bytes) {
	dev_err(cs5535au->card->dev, "diff=%x >= %x buf_bytes.\n",
	curdma, dma->buf_bytes);
	return 0;
	}
	return bytes_to_frames(substream->runtime, curdma);
	}

	static int snd_cs5535audio_capture_open(struct snd_pcm_substream *substream)
	{
	int err;
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;

	runtime->hw = snd_cs5535audio_capture;
	runtime->hw.rates = cs5535au->ac97->rates[AC97_RATES_ADC];
	snd_pcm_limit_hw_rates(runtime);
	cs5535au->capture_substream = substream;
	runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE]);
	if ((err = snd_pcm_hw_constraint_integer(runtime,
	SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
	return err;
	olpc_capture_open(cs5535au->ac97);
	return 0;
	}

	static int snd_cs5535audio_capture_close(struct snd_pcm_substream *substream)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	olpc_capture_close(cs5535au->ac97);
	return 0;
	}

	static int snd_cs5535audio_capture_prepare(struct snd_pcm_substream *substream)
	{
	struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
	return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_LR_ADC_RATE,
	substream->runtime->rate);
	}

	static const struct snd_pcm_ops snd_cs5535audio_playback_ops = {
	.open = snd_cs5535audio_playback_open,
	.close = snd_cs5535audio_playback_close,
	.hw_params = snd_cs5535audio_hw_params,
	.hw_free = snd_cs5535audio_hw_free,
	.prepare = snd_cs5535audio_playback_prepare,
	.trigger = snd_cs5535audio_trigger,
	.pointer = snd_cs5535audio_pcm_pointer,
	};

	static const struct snd_pcm_ops snd_cs5535audio_capture_ops = {
	.open = snd_cs5535audio_capture_open,
	.close = snd_cs5535audio_capture_close,
	.hw_params = snd_cs5535audio_hw_params,
	.hw_free = snd_cs5535audio_hw_free,
	.prepare = snd_cs5535audio_capture_prepare,
	.trigger = snd_cs5535audio_trigger,
	.pointer = snd_cs5535audio_pcm_pointer,
	};

	static const struct cs5535audio_dma_ops snd_cs5535audio_playback_dma_ops = {
	.type = CS5535AUDIO_DMA_PLAYBACK,
	.enable_dma = cs5535audio_playback_enable_dma,
	.disable_dma = cs5535audio_playback_disable_dma,
	.setup_prd = cs5535audio_playback_setup_prd,
	.read_prd = cs5535audio_playback_read_prd,
	.pause_dma = cs5535audio_playback_pause_dma,
	.read_dma_pntr = cs5535audio_playback_read_dma_pntr,
	};

	static const struct cs5535audio_dma_ops snd_cs5535audio_capture_dma_ops = {
	.type = CS5535AUDIO_DMA_CAPTURE,
	.enable_dma = cs5535audio_capture_enable_dma,
	.disable_dma = cs5535audio_capture_disable_dma,
	.setup_prd = cs5535audio_capture_setup_prd,
	.read_prd = cs5535audio_capture_read_prd,
	.pause_dma = cs5535audio_capture_pause_dma,
	.read_dma_pntr = cs5535audio_capture_read_dma_pntr,
	};

	int snd_cs5535audio_pcm(struct cs5535audio *cs5535au)
	{
	struct snd_pcm *pcm;
	int err;

	err = snd_pcm_new(cs5535au->card, "CS5535 Audio", 0, 1, 1, &pcm);
	if (err < 0)
	return err;

	cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK].ops =
	&snd_cs5535audio_playback_dma_ops;
	cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE].ops =
	&snd_cs5535audio_capture_dma_ops;
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
	&snd_cs5535audio_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
	&snd_cs5535audio_capture_ops);

	pcm->private_data = cs5535au;
	pcm->info_flags = 0;
	strcpy(pcm->name, "CS5535 Audio");

	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
	&cs5535au->pci->dev,
	641024, 1281024);
	cs5535au->pcm = pcm;

	return 0;
	}