sound/soc/blackfin/bf5xx-ac97.c - kernel/bruno - Git at Google

 /*
  * bf5xx-ac97.c -- AC97 support for the ADI blackfin chip.
  *
  * Author:	Roy Huang
  * Created:	11th. June 2007
  * Copyright:	Analog Device 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/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/wait.h>
 #include <linux/delay.h>
 #include <linux/slab.h>

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

 #include <asm/irq.h>
 #include <asm/portmux.h>
 #include <linux/mutex.h>
 #include <linux/gpio.h>

 #include "bf5xx-sport.h"
 #include "bf5xx-ac97.h"

 /* Anomaly notes:
  *  05000250 -	AD1980 is running in TDM mode and RFS/TFS are generated by SPORT
  *		contrtoller. But, RFSDIV and TFSDIV are always set to 16*16-1,
  *		while the max AC97 data size is 13*16. The DIV is always larger
  *		than data size. AD73311 and ad2602 are not running in TDM mode.
  *		AD1836 and AD73322 depend on external RFS/TFS only. So, this
  *		anomaly does not affect blackfin sound drivers.
 */

 static struct sport_device *ac97_sport_handle;

 void bf5xx_pcm_to_ac97(struct ac97_frame *dst, const __u16 *src,
 		size_t count, unsigned int chan_mask)
 {
 	while (count--) {
 		dst->ac97_tag = TAG_VALID;
 		if (chan_mask & SP_FL) {
 			dst->ac97_pcm_r = *src++;
 			dst->ac97_tag |= TAG_PCM_RIGHT;
 		}
 		if (chan_mask & SP_FR) {
 			dst->ac97_pcm_l = *src++;
 			dst->ac97_tag |= TAG_PCM_LEFT;

 		}
 #if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
 		if (chan_mask & SP_SR) {
 			dst->ac97_sl = *src++;
 			dst->ac97_tag |= TAG_PCM_SL;
 		}
 		if (chan_mask & SP_SL) {
 			dst->ac97_sr = *src++;
 			dst->ac97_tag |= TAG_PCM_SR;
 		}
 		if (chan_mask & SP_LFE) {
 			dst->ac97_lfe = *src++;
 			dst->ac97_tag |= TAG_PCM_LFE;
 		}
 		if (chan_mask & SP_FC) {
 			dst->ac97_center = *src++;
 			dst->ac97_tag |= TAG_PCM_CENTER;
 		}
 #endif
 		dst++;
 	}
 }
 EXPORT_SYMBOL(bf5xx_pcm_to_ac97);

 void bf5xx_ac97_to_pcm(const struct ac97_frame *src, __u16 *dst,
 		size_t count)
 {
 	while (count--) {
 		*(dst++) = src->ac97_pcm_l;
 		*(dst++) = src->ac97_pcm_r;
 		src++;
 	}
 }
 EXPORT_SYMBOL(bf5xx_ac97_to_pcm);

 static unsigned int sport_tx_curr_frag(struct sport_device *sport)
 {
 	return sport->tx_curr_frag = sport_curr_offset_tx(sport) /
 			sport->tx_fragsize;
 }

 static void enqueue_cmd(struct snd_ac97 *ac97, __u16 addr, __u16 data)
 {
 	struct sport_device *sport = ac97_sport_handle;
 	int *cmd_count = sport->private_data;
 	int nextfrag = sport_tx_curr_frag(sport);
 	struct ac97_frame *nextwrite;

 	sport_incfrag(sport, &nextfrag, 1);

 	nextwrite = (struct ac97_frame *)(sport->tx_buf +
 			nextfrag * sport->tx_fragsize);
 	pr_debug("sport->tx_buf:%p, nextfrag:0x%x nextwrite:%p, cmd_count:%d\n",
 		sport->tx_buf, nextfrag, nextwrite, cmd_count[nextfrag]);
 	nextwrite[cmd_count[nextfrag]].ac97_tag |= TAG_CMD;
 	nextwrite[cmd_count[nextfrag]].ac97_addr = addr;
 	nextwrite[cmd_count[nextfrag]].ac97_data = data;
 	++cmd_count[nextfrag];
 	pr_debug("ac97_sport: Inserting %02x/%04x into fragment %d\n",
 			addr >> 8, data, nextfrag);
 }

 static unsigned short bf5xx_ac97_read(struct snd_ac97 *ac97,
 	unsigned short reg)
 {
 	struct sport_device *sport_handle = ac97_sport_handle;
 	struct ac97_frame out_frame[2], in_frame[2];

 	pr_debug("%s enter 0x%x\n", __func__, reg);

 	/* When dma descriptor is enabled, the register should not be read */
 	if (sport_handle->tx_run || sport_handle->rx_run) {
 		pr_err("Could you send a mail to cliff.cai@analog.com "
 				"to report this?\n");
 		return -EFAULT;
 	}

 	memset(&out_frame, 0, 2 * sizeof(struct ac97_frame));
 	memset(&in_frame, 0, 2 * sizeof(struct ac97_frame));
 	out_frame[0].ac97_tag = TAG_VALID | TAG_CMD;
 	out_frame[0].ac97_addr = ((reg << 8) | 0x8000);
 	sport_send_and_recv(sport_handle, (unsigned char *)&out_frame,
 			(unsigned char *)&in_frame,
 			2 * sizeof(struct ac97_frame));
 	return in_frame[1].ac97_data;
 }

 void bf5xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
 	unsigned short val)
 {
 	struct sport_device *sport_handle = ac97_sport_handle;

 	pr_debug("%s enter 0x%x:0x%04x\n", __func__, reg, val);

 	if (sport_handle->tx_run) {
 		enqueue_cmd(ac97, (reg << 8), val); /* write */
 		enqueue_cmd(ac97, (reg << 8) | 0x8000, 0); /* read back */
 	} else {
 		struct ac97_frame frame;
 		memset(&frame, 0, sizeof(struct ac97_frame));
 		frame.ac97_tag = TAG_VALID | TAG_CMD;
 		frame.ac97_addr = (reg << 8);
 		frame.ac97_data = val;
 		sport_send_and_recv(sport_handle, (unsigned char *)&frame, \
 				NULL, sizeof(struct ac97_frame));
 	}
 }

 static void bf5xx_ac97_warm_reset(struct snd_ac97 *ac97)
 {
 	struct sport_device *sport_handle = ac97_sport_handle;
 	u16 gpio = P_IDENT(sport_handle->pin_req[3]);

 	pr_debug("%s enter\n", __func__);

 	peripheral_free_list(sport_handle->pin_req);
 	gpio_request(gpio, "bf5xx-ac97");
 	gpio_direction_output(gpio, 1);
 	udelay(2);
 	gpio_set_value(gpio, 0);
 	udelay(1);
 	gpio_free(gpio);
 	peripheral_request_list(sport_handle->pin_req, "soc-audio");
 }

 static void bf5xx_ac97_cold_reset(struct snd_ac97 *ac97)
 {
 #ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
 	pr_debug("%s enter\n", __func__);

 	/* It is specified for bf548-ezkit */
 	gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 0);
 	/* Keep reset pin low for 1 ms */
 	mdelay(1);
 	gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 1);
 	/* Wait for bit clock recover */
 	mdelay(1);
 #else
 	pr_info("%s: Not implemented\n", __func__);
 #endif
 }

 static struct snd_ac97_bus_ops bf5xx_ac97_ops = {
 	.read	= bf5xx_ac97_read,
 	.write	= bf5xx_ac97_write,
 	.warm_reset	= bf5xx_ac97_warm_reset,
 	.reset	= bf5xx_ac97_cold_reset,
 };

 #ifdef CONFIG_PM
 static int bf5xx_ac97_suspend(struct snd_soc_dai *dai)
 {
 	struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

 	pr_debug("%s : sport %d\n", __func__, dai->id);
 	if (!dai->active)
 		return 0;
 	if (dai->capture_active)
 		sport_rx_stop(sport);
 	if (dai->playback_active)
 		sport_tx_stop(sport);
 	return 0;
 }

 static int bf5xx_ac97_resume(struct snd_soc_dai *dai)
 {
 	int ret;
 	struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

 	pr_debug("%s : sport %d\n", __func__, dai->id);
 	if (!dai->active)
 		return 0;

 #if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
 	ret = sport_set_multichannel(sport, 16, 0x3FF, 0x3FF, 1);
 #else
 	ret = sport_set_multichannel(sport, 16, 0x1F, 0x1F, 1);
 #endif
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		return -EBUSY;
 	}

 	ret = sport_config_rx(sport, IRFS, 0xF, 0, (16*16-1));
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		return -EBUSY;
 	}

 	ret = sport_config_tx(sport, ITFS, 0xF, 0, (16*16-1));
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		return -EBUSY;
 	}

 	return 0;
 }

 #else
 #define bf5xx_ac97_suspend	NULL
 #define bf5xx_ac97_resume	NULL
 #endif

 static struct snd_soc_dai_driver bfin_ac97_dai = {
 	.bus_control = true,
 	.suspend = bf5xx_ac97_suspend,
 	.resume = bf5xx_ac97_resume,
 	.playback = {
 		.stream_name = "AC97 Playback",
 		.channels_min = 2,
 #if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
 		.channels_max = 6,
 #else
 		.channels_max = 2,
 #endif
 		.rates = SNDRV_PCM_RATE_48000,
 		.formats = SNDRV_PCM_FMTBIT_S16_LE, },
 	.capture = {
 		.stream_name = "AC97 Capture",
 		.channels_min = 2,
 		.channels_max = 2,
 		.rates = SNDRV_PCM_RATE_48000,
 		.formats = SNDRV_PCM_FMTBIT_S16_LE, },
 };

 static const struct snd_soc_component_driver bfin_ac97_component = {
 	.name		= "bfin-ac97",
 };

 static int asoc_bfin_ac97_probe(struct platform_device *pdev)
 {
 	struct sport_device *sport_handle;
 	int ret;

 #ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
 	/* Request PB3 as reset pin */
 	ret = devm_gpio_request_one(&pdev->dev,
 				    CONFIG_SND_BF5XX_RESET_GPIO_NUM,
 				    GPIOF_OUT_INIT_HIGH, "SND_AD198x RESET");
 	if (ret) {
 		dev_err(&pdev->dev,
 			"Failed to request GPIO_%d for reset: %d\n",
 			CONFIG_SND_BF5XX_RESET_GPIO_NUM, ret);
 		return ret;
 	}
 #endif

 	sport_handle = sport_init(pdev, 2, sizeof(struct ac97_frame),
 		PAGE_SIZE);
 	if (!sport_handle) {
 		ret = -ENODEV;
 		goto sport_err;
 	}

 	/*SPORT works in TDM mode to simulate AC97 transfers*/
 #if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
 	ret = sport_set_multichannel(sport_handle, 16, 0x3FF, 0x3FF, 1);
 #else
 	ret = sport_set_multichannel(sport_handle, 16, 0x1F, 0x1F, 1);
 #endif
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		ret = -EBUSY;
 		goto sport_config_err;
 	}

 	ret = sport_config_rx(sport_handle, IRFS, 0xF, 0, (16*16-1));
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		ret = -EBUSY;
 		goto sport_config_err;
 	}

 	ret = sport_config_tx(sport_handle, ITFS, 0xF, 0, (16*16-1));
 	if (ret) {
 		pr_err("SPORT is busy!\n");
 		ret = -EBUSY;
 		goto sport_config_err;
 	}

 	ret = snd_soc_set_ac97_ops(&bf5xx_ac97_ops);
 	if (ret != 0) {
 		dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
 		goto sport_config_err;
 	}

 	ret = snd_soc_register_component(&pdev->dev, &bfin_ac97_component,
 					 &bfin_ac97_dai, 1);
 	if (ret) {
 		pr_err("Failed to register DAI: %d\n", ret);
 		goto sport_config_err;
 	}

 	ac97_sport_handle = sport_handle;

 	return 0;

 sport_config_err:
 	sport_done(sport_handle);
 sport_err:
 	snd_soc_set_ac97_ops(NULL);

 	return ret;
 }

 static int asoc_bfin_ac97_remove(struct platform_device *pdev)
 {
 	struct sport_device *sport_handle = platform_get_drvdata(pdev);

 	snd_soc_unregister_component(&pdev->dev);
 	sport_done(sport_handle);
 	snd_soc_set_ac97_ops(NULL);

 	return 0;
 }

 static struct platform_driver asoc_bfin_ac97_driver = {
 	.driver = {
 			.name = "bfin-ac97",
 	},

 	.probe = asoc_bfin_ac97_probe,
 	.remove = asoc_bfin_ac97_remove,
 };

 module_platform_driver(asoc_bfin_ac97_driver);

 MODULE_AUTHOR("Roy Huang");
 MODULE_DESCRIPTION("AC97 driver for ADI Blackfin");
 MODULE_LICENSE("GPL");
	/*
	* bf5xx-ac97.c -- AC97 support for the ADI blackfin chip.
	*
	* Author: Roy Huang
	* Created: 11th. June 2007
	* Copyright: Analog Device 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/platform_device.h>
	#include <linux/interrupt.h>
	#include <linux/wait.h>
	#include <linux/delay.h>
	#include <linux/slab.h>

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

	#include <asm/irq.h>
	#include <asm/portmux.h>
	#include <linux/mutex.h>
	#include <linux/gpio.h>

	#include "bf5xx-sport.h"
	#include "bf5xx-ac97.h"

	/* Anomaly notes:
	* 05000250 - AD1980 is running in TDM mode and RFS/TFS are generated by SPORT
	* contrtoller. But, RFSDIV and TFSDIV are always set to 16*16-1,
	* while the max AC97 data size is 13*16. The DIV is always larger
	* than data size. AD73311 and ad2602 are not running in TDM mode.
	* AD1836 and AD73322 depend on external RFS/TFS only. So, this
	* anomaly does not affect blackfin sound drivers.
	*/

	static struct sport_device *ac97_sport_handle;

	void bf5xx_pcm_to_ac97(struct ac97_frame dst, const __u16 src,
	size_t count, unsigned int chan_mask)
	{
	while (count--) {
	dst->ac97_tag = TAG_VALID;
	if (chan_mask & SP_FL) {
	dst->ac97_pcm_r = *src++;
	dst->ac97_tag \|= TAG_PCM_RIGHT;
	}
	if (chan_mask & SP_FR) {
	dst->ac97_pcm_l = *src++;
	dst->ac97_tag \|= TAG_PCM_LEFT;

	}
	#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
	if (chan_mask & SP_SR) {
	dst->ac97_sl = *src++;
	dst->ac97_tag \|= TAG_PCM_SL;
	}
	if (chan_mask & SP_SL) {
	dst->ac97_sr = *src++;
	dst->ac97_tag \|= TAG_PCM_SR;
	}
	if (chan_mask & SP_LFE) {
	dst->ac97_lfe = *src++;
	dst->ac97_tag \|= TAG_PCM_LFE;
	}
	if (chan_mask & SP_FC) {
	dst->ac97_center = *src++;
	dst->ac97_tag \|= TAG_PCM_CENTER;
	}
	#endif
	dst++;
	}
	}
	EXPORT_SYMBOL(bf5xx_pcm_to_ac97);

	void bf5xx_ac97_to_pcm(const struct ac97_frame src, __u16 dst,
	size_t count)
	{
	while (count--) {
	*(dst++) = src->ac97_pcm_l;
	*(dst++) = src->ac97_pcm_r;
	src++;
	}
	}
	EXPORT_SYMBOL(bf5xx_ac97_to_pcm);

	static unsigned int sport_tx_curr_frag(struct sport_device *sport)
	{
	return sport->tx_curr_frag = sport_curr_offset_tx(sport) /
	sport->tx_fragsize;
	}

	static void enqueue_cmd(struct snd_ac97 *ac97, __u16 addr, __u16 data)
	{
	struct sport_device *sport = ac97_sport_handle;
	int *cmd_count = sport->private_data;
	int nextfrag = sport_tx_curr_frag(sport);
	struct ac97_frame *nextwrite;

	sport_incfrag(sport, &nextfrag, 1);

	nextwrite = (struct ac97_frame *)(sport->tx_buf +
	nextfrag * sport->tx_fragsize);
	pr_debug("sport->tx_buf:%p, nextfrag:0x%x nextwrite:%p, cmd_count:%d\n",
	sport->tx_buf, nextfrag, nextwrite, cmd_count[nextfrag]);
	nextwrite[cmd_count[nextfrag]].ac97_tag \|= TAG_CMD;
	nextwrite[cmd_count[nextfrag]].ac97_addr = addr;
	nextwrite[cmd_count[nextfrag]].ac97_data = data;
	++cmd_count[nextfrag];
	pr_debug("ac97_sport: Inserting %02x/%04x into fragment %d\n",
	addr >> 8, data, nextfrag);
	}

	static unsigned short bf5xx_ac97_read(struct snd_ac97 *ac97,
	unsigned short reg)
	{
	struct sport_device *sport_handle = ac97_sport_handle;
	struct ac97_frame out_frame[2], in_frame[2];

	pr_debug("%s enter 0x%x\n", __func__, reg);

	/* When dma descriptor is enabled, the register should not be read */
	if (sport_handle->tx_run \|\| sport_handle->rx_run) {
	pr_err("Could you send a mail to cliff.cai@analog.com "
	"to report this?\n");
	return -EFAULT;
	}

	memset(&out_frame, 0, 2 * sizeof(struct ac97_frame));
	memset(&in_frame, 0, 2 * sizeof(struct ac97_frame));
	out_frame[0].ac97_tag = TAG_VALID \| TAG_CMD;
	out_frame[0].ac97_addr = ((reg << 8) \| 0x8000);
	sport_send_and_recv(sport_handle, (unsigned char *)&out_frame,
	(unsigned char *)&in_frame,
	2 * sizeof(struct ac97_frame));
	return in_frame[1].ac97_data;
	}

	void bf5xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
	unsigned short val)
	{
	struct sport_device *sport_handle = ac97_sport_handle;

	pr_debug("%s enter 0x%x:0x%04x\n", __func__, reg, val);

	if (sport_handle->tx_run) {
	enqueue_cmd(ac97, (reg << 8), val); /* write */
	enqueue_cmd(ac97, (reg << 8) \| 0x8000, 0); /* read back */
	} else {
	struct ac97_frame frame;
	memset(&frame, 0, sizeof(struct ac97_frame));
	frame.ac97_tag = TAG_VALID \| TAG_CMD;
	frame.ac97_addr = (reg << 8);
	frame.ac97_data = val;
	sport_send_and_recv(sport_handle, (unsigned char *)&frame, \
	NULL, sizeof(struct ac97_frame));
	}
	}

	static void bf5xx_ac97_warm_reset(struct snd_ac97 *ac97)
	{
	struct sport_device *sport_handle = ac97_sport_handle;
	u16 gpio = P_IDENT(sport_handle->pin_req[3]);

	pr_debug("%s enter\n", __func__);

	peripheral_free_list(sport_handle->pin_req);
	gpio_request(gpio, "bf5xx-ac97");
	gpio_direction_output(gpio, 1);
	udelay(2);
	gpio_set_value(gpio, 0);
	udelay(1);
	gpio_free(gpio);
	peripheral_request_list(sport_handle->pin_req, "soc-audio");
	}

	static void bf5xx_ac97_cold_reset(struct snd_ac97 *ac97)
	{
	#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
	pr_debug("%s enter\n", __func__);

	/* It is specified for bf548-ezkit */
	gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 0);
	/* Keep reset pin low for 1 ms */
	mdelay(1);
	gpio_set_value(CONFIG_SND_BF5XX_RESET_GPIO_NUM, 1);
	/* Wait for bit clock recover */
	mdelay(1);
	#else
	pr_info("%s: Not implemented\n", __func__);
	#endif
	}

	static struct snd_ac97_bus_ops bf5xx_ac97_ops = {
	.read = bf5xx_ac97_read,
	.write = bf5xx_ac97_write,
	.warm_reset = bf5xx_ac97_warm_reset,
	.reset = bf5xx_ac97_cold_reset,
	};

	#ifdef CONFIG_PM
	static int bf5xx_ac97_suspend(struct snd_soc_dai *dai)
	{
	struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

	pr_debug("%s : sport %d\n", __func__, dai->id);
	if (!dai->active)
	return 0;
	if (dai->capture_active)
	sport_rx_stop(sport);
	if (dai->playback_active)
	sport_tx_stop(sport);
	return 0;
	}

	static int bf5xx_ac97_resume(struct snd_soc_dai *dai)
	{
	int ret;
	struct sport_device *sport = snd_soc_dai_get_drvdata(dai);

	pr_debug("%s : sport %d\n", __func__, dai->id);
	if (!dai->active)
	return 0;

	#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
	ret = sport_set_multichannel(sport, 16, 0x3FF, 0x3FF, 1);
	#else
	ret = sport_set_multichannel(sport, 16, 0x1F, 0x1F, 1);
	#endif
	if (ret) {
	pr_err("SPORT is busy!\n");
	return -EBUSY;
	}

	ret = sport_config_rx(sport, IRFS, 0xF, 0, (16*16-1));
	if (ret) {
	pr_err("SPORT is busy!\n");
	return -EBUSY;
	}

	ret = sport_config_tx(sport, ITFS, 0xF, 0, (16*16-1));
	if (ret) {
	pr_err("SPORT is busy!\n");
	return -EBUSY;
	}

	return 0;
	}

	#else
	#define bf5xx_ac97_suspend NULL
	#define bf5xx_ac97_resume NULL
	#endif

	static struct snd_soc_dai_driver bfin_ac97_dai = {
	.bus_control = true,
	.suspend = bf5xx_ac97_suspend,
	.resume = bf5xx_ac97_resume,
	.playback = {
	.stream_name = "AC97 Playback",
	.channels_min = 2,
	#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
	.channels_max = 6,
	#else
	.channels_max = 2,
	#endif
	.rates = SNDRV_PCM_RATE_48000,
	.formats = SNDRV_PCM_FMTBIT_S16_LE, },
	.capture = {
	.stream_name = "AC97 Capture",
	.channels_min = 2,
	.channels_max = 2,
	.rates = SNDRV_PCM_RATE_48000,
	.formats = SNDRV_PCM_FMTBIT_S16_LE, },
	};

	static const struct snd_soc_component_driver bfin_ac97_component = {
	.name = "bfin-ac97",
	};

	static int asoc_bfin_ac97_probe(struct platform_device *pdev)
	{
	struct sport_device *sport_handle;
	int ret;

	#ifdef CONFIG_SND_BF5XX_HAVE_COLD_RESET
	/* Request PB3 as reset pin */
	ret = devm_gpio_request_one(&pdev->dev,
	CONFIG_SND_BF5XX_RESET_GPIO_NUM,
	GPIOF_OUT_INIT_HIGH, "SND_AD198x RESET");
	if (ret) {
	dev_err(&pdev->dev,
	"Failed to request GPIO_%d for reset: %d\n",
	CONFIG_SND_BF5XX_RESET_GPIO_NUM, ret);
	return ret;
	}
	#endif

	sport_handle = sport_init(pdev, 2, sizeof(struct ac97_frame),
	PAGE_SIZE);
	if (!sport_handle) {
	ret = -ENODEV;
	goto sport_err;
	}

	/SPORT works in TDM mode to simulate AC97 transfers/
	#if defined(CONFIG_SND_BF5XX_MULTICHAN_SUPPORT)
	ret = sport_set_multichannel(sport_handle, 16, 0x3FF, 0x3FF, 1);
	#else
	ret = sport_set_multichannel(sport_handle, 16, 0x1F, 0x1F, 1);
	#endif
	if (ret) {
	pr_err("SPORT is busy!\n");
	ret = -EBUSY;
	goto sport_config_err;
	}

	ret = sport_config_rx(sport_handle, IRFS, 0xF, 0, (16*16-1));
	if (ret) {
	pr_err("SPORT is busy!\n");
	ret = -EBUSY;
	goto sport_config_err;
	}

	ret = sport_config_tx(sport_handle, ITFS, 0xF, 0, (16*16-1));
	if (ret) {
	pr_err("SPORT is busy!\n");
	ret = -EBUSY;
	goto sport_config_err;
	}

	ret = snd_soc_set_ac97_ops(&bf5xx_ac97_ops);
	if (ret != 0) {
	dev_err(&pdev->dev, "Failed to set AC'97 ops: %d\n", ret);
	goto sport_config_err;
	}

	ret = snd_soc_register_component(&pdev->dev, &bfin_ac97_component,
	&bfin_ac97_dai, 1);
	if (ret) {
	pr_err("Failed to register DAI: %d\n", ret);
	goto sport_config_err;
	}

	ac97_sport_handle = sport_handle;

	return 0;

	sport_config_err:
	sport_done(sport_handle);
	sport_err:
	snd_soc_set_ac97_ops(NULL);

	return ret;
	}

	static int asoc_bfin_ac97_remove(struct platform_device *pdev)
	{
	struct sport_device *sport_handle = platform_get_drvdata(pdev);

	snd_soc_unregister_component(&pdev->dev);
	sport_done(sport_handle);
	snd_soc_set_ac97_ops(NULL);

	return 0;
	}

	static struct platform_driver asoc_bfin_ac97_driver = {
	.driver = {
	.name = "bfin-ac97",
	},

	.probe = asoc_bfin_ac97_probe,
	.remove = asoc_bfin_ac97_remove,
	};

	module_platform_driver(asoc_bfin_ac97_driver);

	MODULE_AUTHOR("Roy Huang");
	MODULE_DESCRIPTION("AC97 driver for ADI Blackfin");
	MODULE_LICENSE("GPL");