sound/arm/pxa2xx-ac97.c - linux/kernel/git/bpf/bpf-next - Git at Google

 /*
  * linux/sound/pxa2xx-ac97.c -- AC97 support for the Intel PXA2xx chip.
  *
  * Author:	Nicolas Pitre
  * Created:	Dec 02, 2004
  * Copyright:	MontaVista Software Inc.
  *
  * 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/init.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/wait.h>
 #include <linux/delay.h>

 #include <sound/driver.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/ac97_codec.h>
 #include <sound/initval.h>

 #include <asm/irq.h>
 #include <linux/mutex.h>
 #include <asm/hardware.h>
 #include <asm/arch/pxa-regs.h>
 #include <asm/arch/audio.h>

 #include "pxa2xx-pcm.h"


 static DEFINE_MUTEX(car_mutex);
 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
 static volatile long gsr_bits;

 /*
  * Beware PXA27x bugs:
  *
  *   o Slot 12 read from modem space will hang controller.
  *   o CDONE, SDONE interrupt fails after any slot 12 IO.
  *
  * We therefore have an hybrid approach for waiting on SDONE (interrupt or
  * 1 jiffy timeout if interrupt never comes).
  */

 static unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
 {
 	unsigned short val = -1;
 	volatile u32 *reg_addr;

 	mutex_lock(&car_mutex);

 	/* set up primary or secondary codec space */
 	reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE;
 	reg_addr += (reg >> 1);

 	/* start read access across the ac97 link */
 	GSR = GSR_CDONE | GSR_SDONE;
 	gsr_bits = 0;
 	val = *reg_addr;
 	if (reg == AC97_GPIO_STATUS)
 		goto out;
 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
 	    !((GSR | gsr_bits) & GSR_SDONE)) {
 		printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
 				__FUNCTION__, reg, GSR | gsr_bits);
 		val = -1;
 		goto out;
 	}

 	/* valid data now */
 	GSR = GSR_CDONE | GSR_SDONE;
 	gsr_bits = 0;
 	val = *reg_addr;
 	/* but we've just started another cycle... */
 	wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);

 out:	mutex_unlock(&car_mutex);
 	return val;
 }

 static void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val)
 {
 	volatile u32 *reg_addr;

 	mutex_lock(&car_mutex);

 	/* set up primary or secondary codec space */
 	reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE;
 	reg_addr += (reg >> 1);

 	GSR = GSR_CDONE | GSR_SDONE;
 	gsr_bits = 0;
 	*reg_addr = val;
 	if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
 	    !((GSR | gsr_bits) & GSR_CDONE))
 		printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
 				__FUNCTION__, reg, GSR | gsr_bits);

 	mutex_unlock(&car_mutex);
 }

 static void pxa2xx_ac97_reset(struct snd_ac97 *ac97)
 {
 	/* First, try cold reset */
 	GCR &=  GCR_COLD_RST;  /* clear everything but nCRST */
 	GCR &= ~GCR_COLD_RST;  /* then assert nCRST */

 	gsr_bits = 0;
 #ifdef CONFIG_PXA27x
 	/* PXA27x Developers Manual section 13.5.2.2.1 */
 	pxa_set_cken(1 << 31, 1);
 	udelay(5);
 	pxa_set_cken(1 << 31, 0);
 	GCR = GCR_COLD_RST;
 	udelay(50);
 #else
 	GCR = GCR_COLD_RST;
 	GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
 	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
 #endif

 	if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR))) {
 		printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
 				 __FUNCTION__, gsr_bits);

 		/* let's try warm reset */
 		gsr_bits = 0;
 #ifdef CONFIG_PXA27x
 		/* warm reset broken on Bulverde,
 		   so manually keep AC97 reset high */
 		pxa_gpio_mode(113 | GPIO_OUT | GPIO_DFLT_HIGH);
 		udelay(10);
 		GCR |= GCR_WARM_RST;
 		pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
 		udelay(500);
 #else
 		GCR |= GCR_WARM_RST|GCR_PRIRDY_IEN|GCR_SECRDY_IEN;
 		wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
 #endif

 		if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)))
 			printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
 					 __FUNCTION__, gsr_bits);
 	}

 	GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
 	GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
 }

 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
 {
 	long status;

 	status = GSR;
 	if (status) {
 		GSR = status;
 		gsr_bits |= status;
 		wake_up(&gsr_wq);

 #ifdef CONFIG_PXA27x
 		/* Although we don't use those we still need to clear them
 		   since they tend to spuriously trigger when MMC is used
 		   (hardware bug? go figure)... */
 		MISR = MISR_EOC;
 		PISR = PISR_EOC;
 		MCSR = MCSR_EOC;
 #endif

 		return IRQ_HANDLED;
 	}

 	return IRQ_NONE;
 }

 static struct snd_ac97_bus_ops pxa2xx_ac97_ops = {
 	.read	= pxa2xx_ac97_read,
 	.write	= pxa2xx_ac97_write,
 	.reset	= pxa2xx_ac97_reset,
 };

 static struct pxa2xx_pcm_dma_params pxa2xx_ac97_pcm_out = {
 	.name			= "AC97 PCM out",
 	.dev_addr		= __PREG(PCDR),
 	.drcmr			= &DRCMRTXPCDR,
 	.dcmd			= DCMD_INCSRCADDR | DCMD_FLOWTRG |
 				  DCMD_BURST32 | DCMD_WIDTH4,
 };

 static struct pxa2xx_pcm_dma_params pxa2xx_ac97_pcm_in = {
 	.name			= "AC97 PCM in",
 	.dev_addr		= __PREG(PCDR),
 	.drcmr			= &DRCMRRXPCDR,
 	.dcmd			= DCMD_INCTRGADDR | DCMD_FLOWSRC |
 				  DCMD_BURST32 | DCMD_WIDTH4,
 };

 static struct snd_pcm *pxa2xx_ac97_pcm;
 static struct snd_ac97 *pxa2xx_ac97_ac97;

 static int pxa2xx_ac97_pcm_startup(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	pxa2xx_audio_ops_t *platform_ops;
 	int r;

 	runtime->hw.channels_min = 2;
 	runtime->hw.channels_max = 2;

 	r = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 	    AC97_RATES_FRONT_DAC : AC97_RATES_ADC;
 	runtime->hw.rates = pxa2xx_ac97_ac97->rates[r];
 	snd_pcm_limit_hw_rates(runtime);

        	platform_ops = substream->pcm->card->dev->platform_data;
 	if (platform_ops && platform_ops->startup)
 		return platform_ops->startup(substream, platform_ops->priv);
 	else
 		return 0;
 }

 static void pxa2xx_ac97_pcm_shutdown(struct snd_pcm_substream *substream)
 {
 	pxa2xx_audio_ops_t *platform_ops;

        	platform_ops = substream->pcm->card->dev->platform_data;
 	if (platform_ops && platform_ops->shutdown)
 		platform_ops->shutdown(substream, platform_ops->priv);
 }

 static int pxa2xx_ac97_pcm_prepare(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	int reg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 		  AC97_PCM_FRONT_DAC_RATE : AC97_PCM_LR_ADC_RATE;
 	return snd_ac97_set_rate(pxa2xx_ac97_ac97, reg, runtime->rate);
 }

 static struct pxa2xx_pcm_client pxa2xx_ac97_pcm_client = {
 	.playback_params	= &pxa2xx_ac97_pcm_out,
 	.capture_params		= &pxa2xx_ac97_pcm_in,
 	.startup		= pxa2xx_ac97_pcm_startup,
 	.shutdown		= pxa2xx_ac97_pcm_shutdown,
 	.prepare		= pxa2xx_ac97_pcm_prepare,
 };

 #ifdef CONFIG_PM

 static int pxa2xx_ac97_do_suspend(struct snd_card *card, pm_message_t state)
 {
 	pxa2xx_audio_ops_t *platform_ops = card->dev->platform_data;

 	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
 	snd_pcm_suspend_all(pxa2xx_ac97_pcm);
 	snd_ac97_suspend(pxa2xx_ac97_ac97);
 	if (platform_ops && platform_ops->suspend)
 		platform_ops->suspend(platform_ops->priv);
 	GCR |= GCR_ACLINK_OFF;
 	pxa_set_cken(CKEN_AC97, 0);

 	return 0;
 }

 static int pxa2xx_ac97_do_resume(struct snd_card *card)
 {
 	pxa2xx_audio_ops_t *platform_ops = card->dev->platform_data;

 	pxa_set_cken(CKEN_AC97, 1);
 	if (platform_ops && platform_ops->resume)
 		platform_ops->resume(platform_ops->priv);
 	snd_ac97_resume(pxa2xx_ac97_ac97);
 	snd_power_change_state(card, SNDRV_CTL_POWER_D0);

 	return 0;
 }

 static int pxa2xx_ac97_suspend(struct platform_device *dev, pm_message_t state)
 {
 	struct snd_card *card = platform_get_drvdata(dev);
 	int ret = 0;

 	if (card)
 		ret = pxa2xx_ac97_do_suspend(card, PMSG_SUSPEND);

 	return ret;
 }

 static int pxa2xx_ac97_resume(struct platform_device *dev)
 {
 	struct snd_card *card = platform_get_drvdata(dev);
 	int ret = 0;

 	if (card)
 		ret = pxa2xx_ac97_do_resume(card);

 	return ret;
 }

 #else
 #define pxa2xx_ac97_suspend	NULL
 #define pxa2xx_ac97_resume	NULL
 #endif

 static int __devinit pxa2xx_ac97_probe(struct platform_device *dev)
 {
 	struct snd_card *card;
 	struct snd_ac97_bus *ac97_bus;
 	struct snd_ac97_template ac97_template;
 	int ret;

 	ret = -ENOMEM;
 	card = snd_card_new(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
 			    THIS_MODULE, 0);
 	if (!card)
 		goto err;

 	card->dev = &dev->dev;
 	strncpy(card->driver, dev->dev.driver->name, sizeof(card->driver));

 	ret = pxa2xx_pcm_new(card, &pxa2xx_ac97_pcm_client, &pxa2xx_ac97_pcm);
 	if (ret)
 		goto err;

 	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
 	if (ret < 0)
 		goto err;

 	pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
 	pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
 	pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
 	pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
 #ifdef CONFIG_PXA27x
 	/* Use GPIO 113 as AC97 Reset on Bulverde */
 	pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
 #endif
 	pxa_set_cken(CKEN_AC97, 1);

 	ret = snd_ac97_bus(card, 0, &pxa2xx_ac97_ops, NULL, &ac97_bus);
 	if (ret)
 		goto err;
 	memset(&ac97_template, 0, sizeof(ac97_template));
 	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &pxa2xx_ac97_ac97);
 	if (ret)
 		goto err;

 	snprintf(card->shortname, sizeof(card->shortname),
 		 "%s", snd_ac97_get_short_name(pxa2xx_ac97_ac97));
 	snprintf(card->longname, sizeof(card->longname),
 		 "%s (%s)", dev->dev.driver->name, card->mixername);

 	ret = snd_card_register(card);
 	if (ret == 0) {
 		platform_set_drvdata(dev, card);
 		return 0;
 	}

  err:
 	if (card)
 		snd_card_free(card);
 	if (CKEN & (1 << CKEN_AC97)) {
 		GCR |= GCR_ACLINK_OFF;
 		free_irq(IRQ_AC97, NULL);
 		pxa_set_cken(CKEN_AC97, 0);
 	}
 	return ret;
 }

 static int __devexit pxa2xx_ac97_remove(struct platform_device *dev)
 {
 	struct snd_card *card = platform_get_drvdata(dev);

 	if (card) {
 		snd_card_free(card);
 		platform_set_drvdata(dev, NULL);
 		GCR |= GCR_ACLINK_OFF;
 		free_irq(IRQ_AC97, NULL);
 		pxa_set_cken(CKEN_AC97, 0);
 	}

 	return 0;
 }

 static struct platform_driver pxa2xx_ac97_driver = {
 	.probe		= pxa2xx_ac97_probe,
 	.remove		= __devexit_p(pxa2xx_ac97_remove),
 	.suspend	= pxa2xx_ac97_suspend,
 	.resume		= pxa2xx_ac97_resume,
 	.driver		= {
 		.name	= "pxa2xx-ac97",
 	},
 };

 static int __init pxa2xx_ac97_init(void)
 {
 	return platform_driver_register(&pxa2xx_ac97_driver);
 }

 static void __exit pxa2xx_ac97_exit(void)
 {
 	platform_driver_unregister(&pxa2xx_ac97_driver);
 }

 module_init(pxa2xx_ac97_init);
 module_exit(pxa2xx_ac97_exit);

 MODULE_AUTHOR("Nicolas Pitre");
 MODULE_DESCRIPTION("AC97 driver for the Intel PXA2xx chip");
 MODULE_LICENSE("GPL");
	/*
	* linux/sound/pxa2xx-ac97.c -- AC97 support for the Intel PXA2xx chip.
	*
	* Author: Nicolas Pitre
	* Created: Dec 02, 2004
	* Copyright: MontaVista Software Inc.
	*
	* 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/init.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/platform_device.h>
	#include <linux/interrupt.h>
	#include <linux/wait.h>
	#include <linux/delay.h>

	#include <sound/driver.h>
	#include <sound/core.h>
	#include <sound/pcm.h>
	#include <sound/ac97_codec.h>
	#include <sound/initval.h>

	#include <asm/irq.h>
	#include <linux/mutex.h>
	#include <asm/hardware.h>
	#include <asm/arch/pxa-regs.h>
	#include <asm/arch/audio.h>

	#include "pxa2xx-pcm.h"


	static DEFINE_MUTEX(car_mutex);
	static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
	static volatile long gsr_bits;

	/*
	* Beware PXA27x bugs:
	*
	* o Slot 12 read from modem space will hang controller.
	* o CDONE, SDONE interrupt fails after any slot 12 IO.
	*
	* We therefore have an hybrid approach for waiting on SDONE (interrupt or
	* 1 jiffy timeout if interrupt never comes).
	*/

	static unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
	{
	unsigned short val = -1;
	volatile u32 *reg_addr;

	mutex_lock(&car_mutex);

	/* set up primary or secondary codec space */
	reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE;
	reg_addr += (reg >> 1);

	/* start read access across the ac97 link */
	GSR = GSR_CDONE \| GSR_SDONE;
	gsr_bits = 0;
	val = *reg_addr;
	if (reg == AC97_GPIO_STATUS)
	goto out;
	if (wait_event_timeout(gsr_wq, (GSR \| gsr_bits) & GSR_SDONE, 1) <= 0 &&
	!((GSR \| gsr_bits) & GSR_SDONE)) {
	printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
	__FUNCTION__, reg, GSR \| gsr_bits);
	val = -1;
	goto out;
	}

	/* valid data now */
	GSR = GSR_CDONE \| GSR_SDONE;
	gsr_bits = 0;
	val = *reg_addr;
	/* but we've just started another cycle... */
	wait_event_timeout(gsr_wq, (GSR \| gsr_bits) & GSR_SDONE, 1);

	out: mutex_unlock(&car_mutex);
	return val;
	}

	static void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val)
	{
	volatile u32 *reg_addr;

	mutex_lock(&car_mutex);

	/* set up primary or secondary codec space */
	reg_addr = (ac97->num & 1) ? &SAC_REG_BASE : &PAC_REG_BASE;
	reg_addr += (reg >> 1);

	GSR = GSR_CDONE \| GSR_SDONE;
	gsr_bits = 0;
	*reg_addr = val;
	if (wait_event_timeout(gsr_wq, (GSR \| gsr_bits) & GSR_CDONE, 1) <= 0 &&
	!((GSR \| gsr_bits) & GSR_CDONE))
	printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
	__FUNCTION__, reg, GSR \| gsr_bits);

	mutex_unlock(&car_mutex);
	}

	static void pxa2xx_ac97_reset(struct snd_ac97 *ac97)
	{
	/* First, try cold reset */
	GCR &= GCR_COLD_RST; /* clear everything but nCRST */
	GCR &= ~GCR_COLD_RST; /* then assert nCRST */

	gsr_bits = 0;
	#ifdef CONFIG_PXA27x
	/* PXA27x Developers Manual section 13.5.2.2.1 */
	pxa_set_cken(1 << 31, 1);
	udelay(5);
	pxa_set_cken(1 << 31, 0);
	GCR = GCR_COLD_RST;
	udelay(50);
	#else
	GCR = GCR_COLD_RST;
	GCR \|= GCR_CDONE_IE\|GCR_SDONE_IE;
	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR \| GSR_SCR), 1);
	#endif

	if (!((GSR \| gsr_bits) & (GSR_PCR \| GSR_SCR))) {
	printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
	__FUNCTION__, gsr_bits);

	/* let's try warm reset */
	gsr_bits = 0;
	#ifdef CONFIG_PXA27x
	/* warm reset broken on Bulverde,
	so manually keep AC97 reset high */
	pxa_gpio_mode(113 \| GPIO_OUT \| GPIO_DFLT_HIGH);
	udelay(10);
	GCR \|= GCR_WARM_RST;
	pxa_gpio_mode(113 \| GPIO_ALT_FN_2_OUT);
	udelay(500);
	#else
	GCR \|= GCR_WARM_RST\|GCR_PRIRDY_IEN\|GCR_SECRDY_IEN;
	wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR \| GSR_SCR), 1);
	#endif

	if (!((GSR \| gsr_bits) & (GSR_PCR \| GSR_SCR)))
	printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
	__FUNCTION__, gsr_bits);
	}

	GCR &= ~(GCR_PRIRDY_IEN\|GCR_SECRDY_IEN);
	GCR \|= GCR_SDONE_IE\|GCR_CDONE_IE;
	}

	static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
	{
	long status;

	status = GSR;
	if (status) {
	GSR = status;
	gsr_bits \|= status;
	wake_up(&gsr_wq);

	#ifdef CONFIG_PXA27x
	/* Although we don't use those we still need to clear them
	since they tend to spuriously trigger when MMC is used
	(hardware bug? go figure)... */
	MISR = MISR_EOC;
	PISR = PISR_EOC;
	MCSR = MCSR_EOC;
	#endif

	return IRQ_HANDLED;
	}

	return IRQ_NONE;
	}

	static struct snd_ac97_bus_ops pxa2xx_ac97_ops = {
	.read = pxa2xx_ac97_read,
	.write = pxa2xx_ac97_write,
	.reset = pxa2xx_ac97_reset,
	};

	static struct pxa2xx_pcm_dma_params pxa2xx_ac97_pcm_out = {
	.name = "AC97 PCM out",
	.dev_addr = __PREG(PCDR),
	.drcmr = &DRCMRTXPCDR,
	.dcmd = DCMD_INCSRCADDR \| DCMD_FLOWTRG \|
	DCMD_BURST32 \| DCMD_WIDTH4,
	};

	static struct pxa2xx_pcm_dma_params pxa2xx_ac97_pcm_in = {
	.name = "AC97 PCM in",
	.dev_addr = __PREG(PCDR),
	.drcmr = &DRCMRRXPCDR,
	.dcmd = DCMD_INCTRGADDR \| DCMD_FLOWSRC \|
	DCMD_BURST32 \| DCMD_WIDTH4,
	};

	static struct snd_pcm *pxa2xx_ac97_pcm;
	static struct snd_ac97 *pxa2xx_ac97_ac97;

	static int pxa2xx_ac97_pcm_startup(struct snd_pcm_substream *substream)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;
	pxa2xx_audio_ops_t *platform_ops;
	int r;

	runtime->hw.channels_min = 2;
	runtime->hw.channels_max = 2;

	r = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
	AC97_RATES_FRONT_DAC : AC97_RATES_ADC;
	runtime->hw.rates = pxa2xx_ac97_ac97->rates[r];
	snd_pcm_limit_hw_rates(runtime);

	platform_ops = substream->pcm->card->dev->platform_data;
	if (platform_ops && platform_ops->startup)
	return platform_ops->startup(substream, platform_ops->priv);
	else
	return 0;
	}

	static void pxa2xx_ac97_pcm_shutdown(struct snd_pcm_substream *substream)
	{
	pxa2xx_audio_ops_t *platform_ops;

	platform_ops = substream->pcm->card->dev->platform_data;
	if (platform_ops && platform_ops->shutdown)
	platform_ops->shutdown(substream, platform_ops->priv);
	}

	static int pxa2xx_ac97_pcm_prepare(struct snd_pcm_substream *substream)
	{
	struct snd_pcm_runtime *runtime = substream->runtime;
	int reg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
	AC97_PCM_FRONT_DAC_RATE : AC97_PCM_LR_ADC_RATE;
	return snd_ac97_set_rate(pxa2xx_ac97_ac97, reg, runtime->rate);
	}

	static struct pxa2xx_pcm_client pxa2xx_ac97_pcm_client = {
	.playback_params = &pxa2xx_ac97_pcm_out,
	.capture_params = &pxa2xx_ac97_pcm_in,
	.startup = pxa2xx_ac97_pcm_startup,
	.shutdown = pxa2xx_ac97_pcm_shutdown,
	.prepare = pxa2xx_ac97_pcm_prepare,
	};

	#ifdef CONFIG_PM

	static int pxa2xx_ac97_do_suspend(struct snd_card *card, pm_message_t state)
	{
	pxa2xx_audio_ops_t *platform_ops = card->dev->platform_data;

	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
	snd_pcm_suspend_all(pxa2xx_ac97_pcm);
	snd_ac97_suspend(pxa2xx_ac97_ac97);
	if (platform_ops && platform_ops->suspend)
	platform_ops->suspend(platform_ops->priv);
	GCR \|= GCR_ACLINK_OFF;
	pxa_set_cken(CKEN_AC97, 0);

	return 0;
	}

	static int pxa2xx_ac97_do_resume(struct snd_card *card)
	{
	pxa2xx_audio_ops_t *platform_ops = card->dev->platform_data;

	pxa_set_cken(CKEN_AC97, 1);
	if (platform_ops && platform_ops->resume)
	platform_ops->resume(platform_ops->priv);
	snd_ac97_resume(pxa2xx_ac97_ac97);
	snd_power_change_state(card, SNDRV_CTL_POWER_D0);

	return 0;
	}

	static int pxa2xx_ac97_suspend(struct platform_device *dev, pm_message_t state)
	{
	struct snd_card *card = platform_get_drvdata(dev);
	int ret = 0;

	if (card)
	ret = pxa2xx_ac97_do_suspend(card, PMSG_SUSPEND);

	return ret;
	}

	static int pxa2xx_ac97_resume(struct platform_device *dev)
	{
	struct snd_card *card = platform_get_drvdata(dev);
	int ret = 0;

	if (card)
	ret = pxa2xx_ac97_do_resume(card);

	return ret;
	}

	#else
	#define pxa2xx_ac97_suspend NULL
	#define pxa2xx_ac97_resume NULL
	#endif

	static int __devinit pxa2xx_ac97_probe(struct platform_device *dev)
	{
	struct snd_card *card;
	struct snd_ac97_bus *ac97_bus;
	struct snd_ac97_template ac97_template;
	int ret;

	ret = -ENOMEM;
	card = snd_card_new(SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
	THIS_MODULE, 0);
	if (!card)
	goto err;

	card->dev = &dev->dev;
	strncpy(card->driver, dev->dev.driver->name, sizeof(card->driver));

	ret = pxa2xx_pcm_new(card, &pxa2xx_ac97_pcm_client, &pxa2xx_ac97_pcm);
	if (ret)
	goto err;

	ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
	if (ret < 0)
	goto err;

	pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
	pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
	pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
	pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
	#ifdef CONFIG_PXA27x
	/* Use GPIO 113 as AC97 Reset on Bulverde */
	pxa_gpio_mode(113 \| GPIO_ALT_FN_2_OUT);
	#endif
	pxa_set_cken(CKEN_AC97, 1);

	ret = snd_ac97_bus(card, 0, &pxa2xx_ac97_ops, NULL, &ac97_bus);
	if (ret)
	goto err;
	memset(&ac97_template, 0, sizeof(ac97_template));
	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &pxa2xx_ac97_ac97);
	if (ret)
	goto err;

	snprintf(card->shortname, sizeof(card->shortname),
	"%s", snd_ac97_get_short_name(pxa2xx_ac97_ac97));
	snprintf(card->longname, sizeof(card->longname),
	"%s (%s)", dev->dev.driver->name, card->mixername);

	ret = snd_card_register(card);
	if (ret == 0) {
	platform_set_drvdata(dev, card);
	return 0;
	}

	err:
	if (card)
	snd_card_free(card);
	if (CKEN & (1 << CKEN_AC97)) {
	GCR \|= GCR_ACLINK_OFF;
	free_irq(IRQ_AC97, NULL);
	pxa_set_cken(CKEN_AC97, 0);
	}
	return ret;
	}

	static int __devexit pxa2xx_ac97_remove(struct platform_device *dev)
	{
	struct snd_card *card = platform_get_drvdata(dev);

	if (card) {
	snd_card_free(card);
	platform_set_drvdata(dev, NULL);
	GCR \|= GCR_ACLINK_OFF;
	free_irq(IRQ_AC97, NULL);
	pxa_set_cken(CKEN_AC97, 0);
	}

	return 0;
	}

	static struct platform_driver pxa2xx_ac97_driver = {
	.probe = pxa2xx_ac97_probe,
	.remove = __devexit_p(pxa2xx_ac97_remove),
	.suspend = pxa2xx_ac97_suspend,
	.resume = pxa2xx_ac97_resume,
	.driver = {
	.name = "pxa2xx-ac97",
	},
	};

	static int __init pxa2xx_ac97_init(void)
	{
	return platform_driver_register(&pxa2xx_ac97_driver);
	}

	static void __exit pxa2xx_ac97_exit(void)
	{
	platform_driver_unregister(&pxa2xx_ac97_driver);
	}

	module_init(pxa2xx_ac97_init);
	module_exit(pxa2xx_ac97_exit);

	MODULE_AUTHOR("Nicolas Pitre");
	MODULE_DESCRIPTION("AC97 driver for the Intel PXA2xx chip");
	MODULE_LICENSE("GPL");