sound/soc/codecs/tlv320aic26.c - kernel/msm - Gitiles

 /*
  * Texas Instruments TLV320AIC26 low power audio CODEC
  * ALSA SoC CODEC driver
  *
  * Copyright (C) 2008 Secret Lab Technologies Ltd.
  */

 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/delay.h>
 #include <linux/pm.h>
 #include <linux/device.h>
 #include <linux/sysfs.h>
 #include <linux/spi/spi.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
 #include <sound/soc-dapm.h>
 #include <sound/soc-of-simple.h>
 #include <sound/initval.h>

 #include "tlv320aic26.h"

 MODULE_DESCRIPTION("ASoC TLV320AIC26 codec driver");
 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 MODULE_LICENSE("GPL");

 /* AIC26 driver private data */
 struct aic26 {
 	struct spi_device *spi;
 	struct snd_soc_codec codec;
 	u16 reg_cache[AIC26_NUM_REGS];	/* shadow registers */
 	int master;
 	int datfm;
 	int mclk;

 	/* Keyclick parameters */
 	int keyclick_amplitude;
 	int keyclick_freq;
 	int keyclick_len;
 };

 /* ---------------------------------------------------------------------
  * Register access routines
  */
 static unsigned int aic26_reg_read(struct snd_soc_codec *codec,
 				   unsigned int reg)
 {
 	struct aic26 *aic26 = codec->private_data;
 	u16 *cache = codec->reg_cache;
 	u16 cmd, value;
 	u8 buffer[2];
 	int rc;

 	if (reg >= AIC26_NUM_REGS) {
 		WARN_ON_ONCE(1);
 		return 0;
 	}

 	/* Do SPI transfer; first 16bits are command; remaining is
 	 * register contents */
 	cmd = AIC26_READ_COMMAND_WORD(reg);
 	buffer[0] = (cmd >> 8) & 0xff;
 	buffer[1] = cmd & 0xff;
 	rc = spi_write_then_read(aic26->spi, buffer, 2, buffer, 2);
 	if (rc) {
 		dev_err(&aic26->spi->dev, "AIC26 reg read error\n");
 		return -EIO;
 	}
 	value = (buffer[0] << 8) | buffer[1];

 	/* Update the cache before returning with the value */
 	cache[reg] = value;
 	return value;
 }

 static unsigned int aic26_reg_read_cache(struct snd_soc_codec *codec,
 					 unsigned int reg)
 {
 	u16 *cache = codec->reg_cache;

 	if (reg >= AIC26_NUM_REGS) {
 		WARN_ON_ONCE(1);
 		return 0;
 	}

 	return cache[reg];
 }

 static int aic26_reg_write(struct snd_soc_codec *codec, unsigned int reg,
 			   unsigned int value)
 {
 	struct aic26 *aic26 = codec->private_data;
 	u16 *cache = codec->reg_cache;
 	u16 cmd;
 	u8 buffer[4];
 	int rc;

 	if (reg >= AIC26_NUM_REGS) {
 		WARN_ON_ONCE(1);
 		return -EINVAL;
 	}

 	/* Do SPI transfer; first 16bits are command; remaining is data
 	 * to write into register */
 	cmd = AIC26_WRITE_COMMAND_WORD(reg);
 	buffer[0] = (cmd >> 8) & 0xff;
 	buffer[1] = cmd & 0xff;
 	buffer[2] = value >> 8;
 	buffer[3] = value;
 	rc = spi_write(aic26->spi, buffer, 4);
 	if (rc) {
 		dev_err(&aic26->spi->dev, "AIC26 reg read error\n");
 		return -EIO;
 	}

 	/* update cache before returning */
 	cache[reg] = value;
 	return 0;
 }

 /* ---------------------------------------------------------------------
  * Digital Audio Interface Operations
  */
 static int aic26_hw_params(struct snd_pcm_substream *substream,
 			   struct snd_pcm_hw_params *params,
 			   struct snd_soc_dai *dai)
 {
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 	struct snd_soc_device *socdev = rtd->socdev;
 	struct snd_soc_codec *codec = socdev->card->codec;
 	struct aic26 *aic26 = codec->private_data;
 	int fsref, divisor, wlen, pval, jval, dval, qval;
 	u16 reg;

 	dev_dbg(&aic26->spi->dev, "aic26_hw_params(substream=%p, params=%p)\n",
 		substream, params);
 	dev_dbg(&aic26->spi->dev, "rate=%i format=%i\n", params_rate(params),
 		params_format(params));

 	switch (params_rate(params)) {
 	case 8000:  fsref = 48000; divisor = AIC26_DIV_6; break;
 	case 11025: fsref = 44100; divisor = AIC26_DIV_4; break;
 	case 12000: fsref = 48000; divisor = AIC26_DIV_4; break;
 	case 16000: fsref = 48000; divisor = AIC26_DIV_3; break;
 	case 22050: fsref = 44100; divisor = AIC26_DIV_2; break;
 	case 24000: fsref = 48000; divisor = AIC26_DIV_2; break;
 	case 32000: fsref = 48000; divisor = AIC26_DIV_1_5; break;
 	case 44100: fsref = 44100; divisor = AIC26_DIV_1; break;
 	case 48000: fsref = 48000; divisor = AIC26_DIV_1; break;
 	default:
 		dev_dbg(&aic26->spi->dev, "bad rate\n"); return -EINVAL;
 	}

 	/* select data word length */
 	switch (params_format(params)) {
 	case SNDRV_PCM_FORMAT_S8:     wlen = AIC26_WLEN_16; break;
 	case SNDRV_PCM_FORMAT_S16_BE: wlen = AIC26_WLEN_16; break;
 	case SNDRV_PCM_FORMAT_S24_BE: wlen = AIC26_WLEN_24; break;
 	case SNDRV_PCM_FORMAT_S32_BE: wlen = AIC26_WLEN_32; break;
 	default:
 		dev_dbg(&aic26->spi->dev, "bad format\n"); return -EINVAL;
 	}

 	/* Configure PLL */
 	pval = 1;
 	jval = (fsref == 44100) ? 7 : 8;
 	dval = (fsref == 44100) ? 5264 : 1920;
 	qval = 0;
 	reg = 0x8000 | qval << 11 | pval << 8 | jval << 2;
 	aic26_reg_write(codec, AIC26_REG_PLL_PROG1, reg);
 	reg = dval << 2;
 	aic26_reg_write(codec, AIC26_REG_PLL_PROG2, reg);

 	/* Audio Control 3 (master mode, fsref rate) */
 	reg = aic26_reg_read_cache(codec, AIC26_REG_AUDIO_CTRL3);
 	reg &= ~0xf800;
 	if (aic26->master)
 		reg |= 0x0800;
 	if (fsref == 48000)
 		reg |= 0x2000;
 	aic26_reg_write(codec, AIC26_REG_AUDIO_CTRL3, reg);

 	/* Audio Control 1 (FSref divisor) */
 	reg = aic26_reg_read_cache(codec, AIC26_REG_AUDIO_CTRL1);
 	reg &= ~0x0fff;
 	reg |= wlen | aic26->datfm | (divisor << 3) | divisor;
 	aic26_reg_write(codec, AIC26_REG_AUDIO_CTRL1, reg);

 	return 0;
 }

 /**
  * aic26_mute - Mute control to reduce noise when changing audio format
  */
 static int aic26_mute(struct snd_soc_dai *dai, int mute)
 {
 	struct snd_soc_codec *codec = dai->codec;
 	struct aic26 *aic26 = codec->private_data;
 	u16 reg = aic26_reg_read_cache(codec, AIC26_REG_DAC_GAIN);

 	dev_dbg(&aic26->spi->dev, "aic26_mute(dai=%p, mute=%i)\n",
 		dai, mute);

 	if (mute)
 		reg |= 0x8080;
 	else
 		reg &= ~0x8080;
 	aic26_reg_write(codec, AIC26_REG_DAC_GAIN, reg);

 	return 0;
 }

 static int aic26_set_sysclk(struct snd_soc_dai *codec_dai,
 			    int clk_id, unsigned int freq, int dir)
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
 	struct aic26 *aic26 = codec->private_data;

 	dev_dbg(&aic26->spi->dev, "aic26_set_sysclk(dai=%p, clk_id==%i,"
 		" freq=%i, dir=%i)\n",
 		codec_dai, clk_id, freq, dir);

 	/* MCLK needs to fall between 2MHz and 50 MHz */
 	if ((freq < 2000000) || (freq > 50000000))
 		return -EINVAL;

 	aic26->mclk = freq;
 	return 0;
 }

 static int aic26_set_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
 	struct aic26 *aic26 = codec->private_data;

 	dev_dbg(&aic26->spi->dev, "aic26_set_fmt(dai=%p, fmt==%i)\n",
 		codec_dai, fmt);

 	/* set master/slave audio interface */
 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 	case SND_SOC_DAIFMT_CBM_CFM: aic26->master = 1; break;
 	case SND_SOC_DAIFMT_CBS_CFS: aic26->master = 0; break;
 	default:
 		dev_dbg(&aic26->spi->dev, "bad master\n"); return -EINVAL;
 	}

 	/* interface format */
 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 	case SND_SOC_DAIFMT_I2S:     aic26->datfm = AIC26_DATFM_I2S; break;
 	case SND_SOC_DAIFMT_DSP_A:   aic26->datfm = AIC26_DATFM_DSP; break;
 	case SND_SOC_DAIFMT_RIGHT_J: aic26->datfm = AIC26_DATFM_RIGHTJ; break;
 	case SND_SOC_DAIFMT_LEFT_J:  aic26->datfm = AIC26_DATFM_LEFTJ; break;
 	default:
 		dev_dbg(&aic26->spi->dev, "bad format\n"); return -EINVAL;
 	}

 	return 0;
 }

 /* ---------------------------------------------------------------------
  * Digital Audio Interface Definition
  */
 #define AIC26_RATES	(SNDRV_PCM_RATE_8000  | SNDRV_PCM_RATE_11025 |\
 			 SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 |\
 			 SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |\
 			 SNDRV_PCM_RATE_48000)
 #define AIC26_FORMATS	(SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_S16_BE |\
 			 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)

 static struct snd_soc_dai_ops aic26_dai_ops = {
 	.hw_params	= aic26_hw_params,
 	.digital_mute	= aic26_mute,
 	.set_sysclk	= aic26_set_sysclk,
 	.set_fmt	= aic26_set_fmt,
 };

 struct snd_soc_dai aic26_dai = {
 	.name = "tlv320aic26",
 	.playback = {
 		.stream_name = "Playback",
 		.channels_min = 2,
 		.channels_max = 2,
 		.rates = AIC26_RATES,
 		.formats = AIC26_FORMATS,
 	},
 	.capture = {
 		.stream_name = "Capture",
 		.channels_min = 2,
 		.channels_max = 2,
 		.rates = AIC26_RATES,
 		.formats = AIC26_FORMATS,
 	},
 	.ops = &aic26_dai_ops,
 };
 EXPORT_SYMBOL_GPL(aic26_dai);

 /* ---------------------------------------------------------------------
  * ALSA controls
  */
 static const char *aic26_capture_src_text[] = {"Mic", "Aux"};
 static const struct soc_enum aic26_capture_src_enum =
 	SOC_ENUM_SINGLE(AIC26_REG_AUDIO_CTRL1, 12, 2, aic26_capture_src_text);

 static const struct snd_kcontrol_new aic26_snd_controls[] = {
 	/* Output */
 	SOC_DOUBLE("PCM Playback Volume", AIC26_REG_DAC_GAIN, 8, 0, 0x7f, 1),
 	SOC_DOUBLE("PCM Playback Switch", AIC26_REG_DAC_GAIN, 15, 7, 1, 1),
 	SOC_SINGLE("PCM Capture Volume", AIC26_REG_ADC_GAIN, 8, 0x7f, 0),
 	SOC_SINGLE("PCM Capture Mute", AIC26_REG_ADC_GAIN, 15, 1, 1),
 	SOC_SINGLE("Keyclick activate", AIC26_REG_AUDIO_CTRL2, 15, 0x1, 0),
 	SOC_SINGLE("Keyclick amplitude", AIC26_REG_AUDIO_CTRL2, 12, 0x7, 0),
 	SOC_SINGLE("Keyclick frequency", AIC26_REG_AUDIO_CTRL2, 8, 0x7, 0),
 	SOC_SINGLE("Keyclick period", AIC26_REG_AUDIO_CTRL2, 4, 0xf, 0),
 	SOC_ENUM("Capture Source", aic26_capture_src_enum),
 };

 /* ---------------------------------------------------------------------
  * SoC CODEC portion of driver: probe and release routines
  */
 static int aic26_probe(struct platform_device *pdev)
 {
 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 	struct snd_soc_codec *codec;
 	struct snd_kcontrol *kcontrol;
 	struct aic26 *aic26;
 	int i, ret, err;

 	dev_info(&pdev->dev, "Probing AIC26 SoC CODEC driver\n");
 	dev_dbg(&pdev->dev, "socdev=%p\n", socdev);
 	dev_dbg(&pdev->dev, "codec_data=%p\n", socdev->codec_data);

 	/* Fetch the relevant aic26 private data here (it's already been
 	 * stored in the .codec pointer) */
 	aic26 = socdev->codec_data;
 	if (aic26 == NULL) {
 		dev_err(&pdev->dev, "aic26: missing codec pointer\n");
 		return -ENODEV;
 	}
 	codec = &aic26->codec;
 	socdev->card->codec = codec;

 	dev_dbg(&pdev->dev, "Registering PCMs, dev=%p, socdev->dev=%p\n",
 		&pdev->dev, socdev->dev);
 	/* register pcms */
 	ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "aic26: failed to create pcms\n");
 		return -ENODEV;
 	}

 	/* register controls */
 	dev_dbg(&pdev->dev, "Registering controls\n");
 	for (i = 0; i < ARRAY_SIZE(aic26_snd_controls); i++) {
 		kcontrol = snd_soc_cnew(&aic26_snd_controls[i], codec, NULL);
 		err = snd_ctl_add(codec->card, kcontrol);
 		WARN_ON(err < 0);
 	}

 	/* CODEC is setup, we can register the card now */
 	dev_dbg(&pdev->dev, "Registering card\n");
 	ret = snd_soc_init_card(socdev);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "aic26: failed to register card\n");
 		goto card_err;
 	}
 	return 0;

  card_err:
 	snd_soc_free_pcms(socdev);
 	return ret;
 }

 static int aic26_remove(struct platform_device *pdev)
 {
 	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 	snd_soc_free_pcms(socdev);
 	return 0;
 }

 struct snd_soc_codec_device aic26_soc_codec_dev = {
 	.probe = aic26_probe,
 	.remove = aic26_remove,
 };
 EXPORT_SYMBOL_GPL(aic26_soc_codec_dev);

 /* ---------------------------------------------------------------------
  * SPI device portion of driver: sysfs files for debugging
  */

 static ssize_t aic26_keyclick_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct aic26 *aic26 = dev_get_drvdata(dev);
 	int val, amp, freq, len;

 	val = aic26_reg_read_cache(&aic26->codec, AIC26_REG_AUDIO_CTRL2);
 	amp = (val >> 12) & 0x7;
 	freq = (125 << ((val >> 8) & 0x7)) >> 1;
 	len = 2 * (1 + ((val >> 4) & 0xf));

 	return sprintf(buf, "amp=%x freq=%iHz len=%iclks\n", amp, freq, len);
 }

 /* Any write to the keyclick attribute will trigger the keyclick event */
 static ssize_t aic26_keyclick_set(struct device *dev,
 				  struct device_attribute *attr,
 				  const char *buf, size_t count)
 {
 	struct aic26 *aic26 = dev_get_drvdata(dev);
 	int val;

 	val = aic26_reg_read_cache(&aic26->codec, AIC26_REG_AUDIO_CTRL2);
 	val |= 0x8000;
 	aic26_reg_write(&aic26->codec, AIC26_REG_AUDIO_CTRL2, val);

 	return count;
 }

 static DEVICE_ATTR(keyclick, 0644, aic26_keyclick_show, aic26_keyclick_set);

 /* ---------------------------------------------------------------------
  * SPI device portion of driver: probe and release routines and SPI
  * 				 driver registration.
  */
 static int aic26_spi_probe(struct spi_device *spi)
 {
 	struct aic26 *aic26;
 	int ret, i, reg;

 	dev_dbg(&spi->dev, "probing tlv320aic26 spi device\n");

 	/* Allocate driver data */
 	aic26 = kzalloc(sizeof *aic26, GFP_KERNEL);
 	if (!aic26)
 		return -ENOMEM;

 	/* Initialize the driver data */
 	aic26->spi = spi;
 	dev_set_drvdata(&spi->dev, aic26);

 	/* Setup what we can in the codec structure so that the register
 	 * access functions will work as expected.  More will be filled
 	 * out when it is probed by the SoC CODEC part of this driver */
 	aic26->codec.private_data = aic26;
 	aic26->codec.name = "aic26";
 	aic26->codec.owner = THIS_MODULE;
 	aic26->codec.dai = &aic26_dai;
 	aic26->codec.num_dai = 1;
 	aic26->codec.read = aic26_reg_read;
 	aic26->codec.write = aic26_reg_write;
 	aic26->master = 1;
 	mutex_init(&aic26->codec.mutex);
 	INIT_LIST_HEAD(&aic26->codec.dapm_widgets);
 	INIT_LIST_HEAD(&aic26->codec.dapm_paths);
 	aic26->codec.reg_cache_size = AIC26_NUM_REGS;
 	aic26->codec.reg_cache = aic26->reg_cache;

 	aic26_dai.dev = &spi->dev;
 	ret = snd_soc_register_dai(&aic26_dai);
 	if (ret != 0) {
 		dev_err(&spi->dev, "Failed to register DAI: %d\n", ret);
 		kfree(aic26);
 		return ret;
 	}

 	/* Reset the codec to power on defaults */
 	aic26_reg_write(&aic26->codec, AIC26_REG_RESET, 0xBB00);

 	/* Power up CODEC */
 	aic26_reg_write(&aic26->codec, AIC26_REG_POWER_CTRL, 0);

 	/* Audio Control 3 (master mode, fsref rate) */
 	reg = aic26_reg_read(&aic26->codec, AIC26_REG_AUDIO_CTRL3);
 	reg &= ~0xf800;
 	reg |= 0x0800; /* set master mode */
 	aic26_reg_write(&aic26->codec, AIC26_REG_AUDIO_CTRL3, reg);

 	/* Fill register cache */
 	for (i = 0; i < ARRAY_SIZE(aic26->reg_cache); i++)
 		aic26_reg_read(&aic26->codec, i);

 	/* Register the sysfs files for debugging */
 	/* Create SysFS files */
 	ret = device_create_file(&spi->dev, &dev_attr_keyclick);
 	if (ret)
 		dev_info(&spi->dev, "error creating sysfs files\n");

 #if defined(CONFIG_SND_SOC_OF_SIMPLE)
 	/* Tell the of_soc helper about this codec */
 	of_snd_soc_register_codec(&aic26_soc_codec_dev, aic26, &aic26_dai,
 				  spi->dev.archdata.of_node);
 #endif

 	dev_dbg(&spi->dev, "SPI device initialized\n");
 	return 0;
 }

 static int aic26_spi_remove(struct spi_device *spi)
 {
 	struct aic26 *aic26 = dev_get_drvdata(&spi->dev);

 	snd_soc_unregister_dai(&aic26_dai);
 	kfree(aic26);

 	return 0;
 }

 static struct spi_driver aic26_spi = {
 	.driver = {
 		.name = "tlv320aic26",
 		.owner = THIS_MODULE,
 	},
 	.probe = aic26_spi_probe,
 	.remove = aic26_spi_remove,
 };

 static int __init aic26_init(void)
 {
 	return spi_register_driver(&aic26_spi);
 }
 module_init(aic26_init);

 static void __exit aic26_exit(void)
 {
 	spi_unregister_driver(&aic26_spi);
 }
 module_exit(aic26_exit);
	/*
	* Texas Instruments TLV320AIC26 low power audio CODEC
	* ALSA SoC CODEC driver
	*
	* Copyright (C) 2008 Secret Lab Technologies Ltd.
	*/

	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/init.h>
	#include <linux/delay.h>
	#include <linux/pm.h>
	#include <linux/device.h>
	#include <linux/sysfs.h>
	#include <linux/spi/spi.h>
	#include <sound/core.h>
	#include <sound/pcm.h>
	#include <sound/pcm_params.h>
	#include <sound/soc.h>
	#include <sound/soc-dapm.h>
	#include <sound/soc-of-simple.h>
	#include <sound/initval.h>

	#include "tlv320aic26.h"

	MODULE_DESCRIPTION("ASoC TLV320AIC26 codec driver");
	MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
	MODULE_LICENSE("GPL");

	/* AIC26 driver private data */
	struct aic26 {
	struct spi_device *spi;
	struct snd_soc_codec codec;
	u16 reg_cache[AIC26_NUM_REGS]; /* shadow registers */
	int master;
	int datfm;
	int mclk;

	/* Keyclick parameters */
	int keyclick_amplitude;
	int keyclick_freq;
	int keyclick_len;
	};

	/* ---------------------------------------------------------------------
	* Register access routines
	*/
	static unsigned int aic26_reg_read(struct snd_soc_codec *codec,
	unsigned int reg)
	{
	struct aic26 *aic26 = codec->private_data;
	u16 *cache = codec->reg_cache;
	u16 cmd, value;
	u8 buffer[2];
	int rc;

	if (reg >= AIC26_NUM_REGS) {
	WARN_ON_ONCE(1);
	return 0;
	}

	/* Do SPI transfer; first 16bits are command; remaining is
	* register contents */
	cmd = AIC26_READ_COMMAND_WORD(reg);
	buffer[0] = (cmd >> 8) & 0xff;
	buffer[1] = cmd & 0xff;
	rc = spi_write_then_read(aic26->spi, buffer, 2, buffer, 2);
	if (rc) {
	dev_err(&aic26->spi->dev, "AIC26 reg read error\n");
	return -EIO;
	}
	value = (buffer[0] << 8) \| buffer[1];

	/* Update the cache before returning with the value */
	cache[reg] = value;
	return value;
	}

	static unsigned int aic26_reg_read_cache(struct snd_soc_codec *codec,
	unsigned int reg)
	{
	u16 *cache = codec->reg_cache;

	if (reg >= AIC26_NUM_REGS) {
	WARN_ON_ONCE(1);
	return 0;
	}

	return cache[reg];
	}

	static int aic26_reg_write(struct snd_soc_codec *codec, unsigned int reg,
	unsigned int value)
	{
	struct aic26 *aic26 = codec->private_data;
	u16 *cache = codec->reg_cache;
	u16 cmd;
	u8 buffer[4];
	int rc;

	if (reg >= AIC26_NUM_REGS) {
	WARN_ON_ONCE(1);
	return -EINVAL;
	}

	/* Do SPI transfer; first 16bits are command; remaining is data
	* to write into register */
	cmd = AIC26_WRITE_COMMAND_WORD(reg);
	buffer[0] = (cmd >> 8) & 0xff;
	buffer[1] = cmd & 0xff;
	buffer[2] = value >> 8;
	buffer[3] = value;
	rc = spi_write(aic26->spi, buffer, 4);
	if (rc) {
	dev_err(&aic26->spi->dev, "AIC26 reg read error\n");
	return -EIO;
	}

	/* update cache before returning */
	cache[reg] = value;
	return 0;
	}

	/* ---------------------------------------------------------------------
	* Digital Audio Interface Operations
	*/
	static int aic26_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params,
	struct snd_soc_dai *dai)
	{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_device *socdev = rtd->socdev;
	struct snd_soc_codec *codec = socdev->card->codec;
	struct aic26 *aic26 = codec->private_data;
	int fsref, divisor, wlen, pval, jval, dval, qval;
	u16 reg;

	dev_dbg(&aic26->spi->dev, "aic26_hw_params(substream=%p, params=%p)\n",
	substream, params);
	dev_dbg(&aic26->spi->dev, "rate=%i format=%i\n", params_rate(params),
	params_format(params));

	switch (params_rate(params)) {
	case 8000: fsref = 48000; divisor = AIC26_DIV_6; break;
	case 11025: fsref = 44100; divisor = AIC26_DIV_4; break;
	case 12000: fsref = 48000; divisor = AIC26_DIV_4; break;
	case 16000: fsref = 48000; divisor = AIC26_DIV_3; break;
	case 22050: fsref = 44100; divisor = AIC26_DIV_2; break;
	case 24000: fsref = 48000; divisor = AIC26_DIV_2; break;
	case 32000: fsref = 48000; divisor = AIC26_DIV_1_5; break;
	case 44100: fsref = 44100; divisor = AIC26_DIV_1; break;
	case 48000: fsref = 48000; divisor = AIC26_DIV_1; break;
	default:
	dev_dbg(&aic26->spi->dev, "bad rate\n"); return -EINVAL;
	}

	/* select data word length */
	switch (params_format(params)) {
	case SNDRV_PCM_FORMAT_S8: wlen = AIC26_WLEN_16; break;
	case SNDRV_PCM_FORMAT_S16_BE: wlen = AIC26_WLEN_16; break;
	case SNDRV_PCM_FORMAT_S24_BE: wlen = AIC26_WLEN_24; break;
	case SNDRV_PCM_FORMAT_S32_BE: wlen = AIC26_WLEN_32; break;
	default:
	dev_dbg(&aic26->spi->dev, "bad format\n"); return -EINVAL;
	}

	/* Configure PLL */
	pval = 1;
	jval = (fsref == 44100) ? 7 : 8;
	dval = (fsref == 44100) ? 5264 : 1920;
	qval = 0;
	reg = 0x8000 \| qval << 11 \| pval << 8 \| jval << 2;
	aic26_reg_write(codec, AIC26_REG_PLL_PROG1, reg);
	reg = dval << 2;
	aic26_reg_write(codec, AIC26_REG_PLL_PROG2, reg);

	/* Audio Control 3 (master mode, fsref rate) */
	reg = aic26_reg_read_cache(codec, AIC26_REG_AUDIO_CTRL3);
	reg &= ~0xf800;
	if (aic26->master)
	reg \|= 0x0800;
	if (fsref == 48000)
	reg \|= 0x2000;
	aic26_reg_write(codec, AIC26_REG_AUDIO_CTRL3, reg);

	/* Audio Control 1 (FSref divisor) */
	reg = aic26_reg_read_cache(codec, AIC26_REG_AUDIO_CTRL1);
	reg &= ~0x0fff;
	reg \|= wlen \| aic26->datfm \| (divisor << 3) \| divisor;
	aic26_reg_write(codec, AIC26_REG_AUDIO_CTRL1, reg);

	return 0;
	}

	/**
	* aic26_mute - Mute control to reduce noise when changing audio format
	*/
	static int aic26_mute(struct snd_soc_dai *dai, int mute)
	{
	struct snd_soc_codec *codec = dai->codec;
	struct aic26 *aic26 = codec->private_data;
	u16 reg = aic26_reg_read_cache(codec, AIC26_REG_DAC_GAIN);

	dev_dbg(&aic26->spi->dev, "aic26_mute(dai=%p, mute=%i)\n",
	dai, mute);

	if (mute)
	reg \|= 0x8080;
	else
	reg &= ~0x8080;
	aic26_reg_write(codec, AIC26_REG_DAC_GAIN, reg);

	return 0;
	}

	static int aic26_set_sysclk(struct snd_soc_dai *codec_dai,
	int clk_id, unsigned int freq, int dir)
	{
	struct snd_soc_codec *codec = codec_dai->codec;
	struct aic26 *aic26 = codec->private_data;

	dev_dbg(&aic26->spi->dev, "aic26_set_sysclk(dai=%p, clk_id==%i,"
	" freq=%i, dir=%i)\n",
	codec_dai, clk_id, freq, dir);

	/* MCLK needs to fall between 2MHz and 50 MHz */
	if ((freq < 2000000) \|\| (freq > 50000000))
	return -EINVAL;

	aic26->mclk = freq;
	return 0;
	}

	static int aic26_set_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
	{
	struct snd_soc_codec *codec = codec_dai->codec;
	struct aic26 *aic26 = codec->private_data;

	dev_dbg(&aic26->spi->dev, "aic26_set_fmt(dai=%p, fmt==%i)\n",
	codec_dai, fmt);

	/* set master/slave audio interface */
	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
	case SND_SOC_DAIFMT_CBM_CFM: aic26->master = 1; break;
	case SND_SOC_DAIFMT_CBS_CFS: aic26->master = 0; break;
	default:
	dev_dbg(&aic26->spi->dev, "bad master\n"); return -EINVAL;
	}

	/* interface format */
	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
	case SND_SOC_DAIFMT_I2S: aic26->datfm = AIC26_DATFM_I2S; break;
	case SND_SOC_DAIFMT_DSP_A: aic26->datfm = AIC26_DATFM_DSP; break;
	case SND_SOC_DAIFMT_RIGHT_J: aic26->datfm = AIC26_DATFM_RIGHTJ; break;
	case SND_SOC_DAIFMT_LEFT_J: aic26->datfm = AIC26_DATFM_LEFTJ; break;
	default:
	dev_dbg(&aic26->spi->dev, "bad format\n"); return -EINVAL;
	}

	return 0;
	}

	/* ---------------------------------------------------------------------
	* Digital Audio Interface Definition
	*/
	#define AIC26_RATES (SNDRV_PCM_RATE_8000 \| SNDRV_PCM_RATE_11025 \|\
	SNDRV_PCM_RATE_16000 \| SNDRV_PCM_RATE_22050 \|\
	SNDRV_PCM_RATE_32000 \| SNDRV_PCM_RATE_44100 \|\
	SNDRV_PCM_RATE_48000)
	#define AIC26_FORMATS (SNDRV_PCM_FMTBIT_S8 \| SNDRV_PCM_FMTBIT_S16_BE \|\
	SNDRV_PCM_FMTBIT_S24_BE \| SNDRV_PCM_FMTBIT_S32_BE)

	static struct snd_soc_dai_ops aic26_dai_ops = {
	.hw_params = aic26_hw_params,
	.digital_mute = aic26_mute,
	.set_sysclk = aic26_set_sysclk,
	.set_fmt = aic26_set_fmt,
	};

	struct snd_soc_dai aic26_dai = {
	.name = "tlv320aic26",
	.playback = {
	.stream_name = "Playback",
	.channels_min = 2,
	.channels_max = 2,
	.rates = AIC26_RATES,
	.formats = AIC26_FORMATS,
	},
	.capture = {
	.stream_name = "Capture",
	.channels_min = 2,
	.channels_max = 2,
	.rates = AIC26_RATES,
	.formats = AIC26_FORMATS,
	},
	.ops = &aic26_dai_ops,
	};
	EXPORT_SYMBOL_GPL(aic26_dai);

	/* ---------------------------------------------------------------------
	* ALSA controls
	*/
	static const char *aic26_capture_src_text[] = {"Mic", "Aux"};
	static const struct soc_enum aic26_capture_src_enum =
	SOC_ENUM_SINGLE(AIC26_REG_AUDIO_CTRL1, 12, 2, aic26_capture_src_text);

	static const struct snd_kcontrol_new aic26_snd_controls[] = {
	/* Output */
	SOC_DOUBLE("PCM Playback Volume", AIC26_REG_DAC_GAIN, 8, 0, 0x7f, 1),
	SOC_DOUBLE("PCM Playback Switch", AIC26_REG_DAC_GAIN, 15, 7, 1, 1),
	SOC_SINGLE("PCM Capture Volume", AIC26_REG_ADC_GAIN, 8, 0x7f, 0),
	SOC_SINGLE("PCM Capture Mute", AIC26_REG_ADC_GAIN, 15, 1, 1),
	SOC_SINGLE("Keyclick activate", AIC26_REG_AUDIO_CTRL2, 15, 0x1, 0),
	SOC_SINGLE("Keyclick amplitude", AIC26_REG_AUDIO_CTRL2, 12, 0x7, 0),
	SOC_SINGLE("Keyclick frequency", AIC26_REG_AUDIO_CTRL2, 8, 0x7, 0),
	SOC_SINGLE("Keyclick period", AIC26_REG_AUDIO_CTRL2, 4, 0xf, 0),
	SOC_ENUM("Capture Source", aic26_capture_src_enum),
	};

	/* ---------------------------------------------------------------------
	* SoC CODEC portion of driver: probe and release routines
	*/
	static int aic26_probe(struct platform_device *pdev)
	{
	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
	struct snd_soc_codec *codec;
	struct snd_kcontrol *kcontrol;
	struct aic26 *aic26;
	int i, ret, err;

	dev_info(&pdev->dev, "Probing AIC26 SoC CODEC driver\n");
	dev_dbg(&pdev->dev, "socdev=%p\n", socdev);
	dev_dbg(&pdev->dev, "codec_data=%p\n", socdev->codec_data);

	/* Fetch the relevant aic26 private data here (it's already been
	* stored in the .codec pointer) */
	aic26 = socdev->codec_data;
	if (aic26 == NULL) {
	dev_err(&pdev->dev, "aic26: missing codec pointer\n");
	return -ENODEV;
	}
	codec = &aic26->codec;
	socdev->card->codec = codec;

	dev_dbg(&pdev->dev, "Registering PCMs, dev=%p, socdev->dev=%p\n",
	&pdev->dev, socdev->dev);
	/* register pcms */
	ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
	if (ret < 0) {
	dev_err(&pdev->dev, "aic26: failed to create pcms\n");
	return -ENODEV;
	}

	/* register controls */
	dev_dbg(&pdev->dev, "Registering controls\n");
	for (i = 0; i < ARRAY_SIZE(aic26_snd_controls); i++) {
	kcontrol = snd_soc_cnew(&aic26_snd_controls[i], codec, NULL);
	err = snd_ctl_add(codec->card, kcontrol);
	WARN_ON(err < 0);
	}

	/* CODEC is setup, we can register the card now */
	dev_dbg(&pdev->dev, "Registering card\n");
	ret = snd_soc_init_card(socdev);
	if (ret < 0) {
	dev_err(&pdev->dev, "aic26: failed to register card\n");
	goto card_err;
	}
	return 0;

	card_err:
	snd_soc_free_pcms(socdev);
	return ret;
	}

	static int aic26_remove(struct platform_device *pdev)
	{
	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
	snd_soc_free_pcms(socdev);
	return 0;
	}

	struct snd_soc_codec_device aic26_soc_codec_dev = {
	.probe = aic26_probe,
	.remove = aic26_remove,
	};
	EXPORT_SYMBOL_GPL(aic26_soc_codec_dev);

	/* ---------------------------------------------------------------------
	* SPI device portion of driver: sysfs files for debugging
	*/

	static ssize_t aic26_keyclick_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct aic26 *aic26 = dev_get_drvdata(dev);
	int val, amp, freq, len;

	val = aic26_reg_read_cache(&aic26->codec, AIC26_REG_AUDIO_CTRL2);
	amp = (val >> 12) & 0x7;
	freq = (125 << ((val >> 8) & 0x7)) >> 1;
	len = 2 * (1 + ((val >> 4) & 0xf));

	return sprintf(buf, "amp=%x freq=%iHz len=%iclks\n", amp, freq, len);
	}

	/* Any write to the keyclick attribute will trigger the keyclick event */
	static ssize_t aic26_keyclick_set(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t count)
	{
	struct aic26 *aic26 = dev_get_drvdata(dev);
	int val;

	val = aic26_reg_read_cache(&aic26->codec, AIC26_REG_AUDIO_CTRL2);
	val \|= 0x8000;
	aic26_reg_write(&aic26->codec, AIC26_REG_AUDIO_CTRL2, val);

	return count;
	}

	static DEVICE_ATTR(keyclick, 0644, aic26_keyclick_show, aic26_keyclick_set);

	/* ---------------------------------------------------------------------
	* SPI device portion of driver: probe and release routines and SPI
	* driver registration.
	*/
	static int aic26_spi_probe(struct spi_device *spi)
	{
	struct aic26 *aic26;
	int ret, i, reg;

	dev_dbg(&spi->dev, "probing tlv320aic26 spi device\n");

	/* Allocate driver data */
	aic26 = kzalloc(sizeof *aic26, GFP_KERNEL);
	if (!aic26)
	return -ENOMEM;

	/* Initialize the driver data */
	aic26->spi = spi;
	dev_set_drvdata(&spi->dev, aic26);

	/* Setup what we can in the codec structure so that the register
	* access functions will work as expected. More will be filled
	* out when it is probed by the SoC CODEC part of this driver */
	aic26->codec.private_data = aic26;
	aic26->codec.name = "aic26";
	aic26->codec.owner = THIS_MODULE;
	aic26->codec.dai = &aic26_dai;
	aic26->codec.num_dai = 1;
	aic26->codec.read = aic26_reg_read;
	aic26->codec.write = aic26_reg_write;
	aic26->master = 1;
	mutex_init(&aic26->codec.mutex);
	INIT_LIST_HEAD(&aic26->codec.dapm_widgets);
	INIT_LIST_HEAD(&aic26->codec.dapm_paths);
	aic26->codec.reg_cache_size = AIC26_NUM_REGS;
	aic26->codec.reg_cache = aic26->reg_cache;

	aic26_dai.dev = &spi->dev;
	ret = snd_soc_register_dai(&aic26_dai);
	if (ret != 0) {
	dev_err(&spi->dev, "Failed to register DAI: %d\n", ret);
	kfree(aic26);
	return ret;
	}

	/* Reset the codec to power on defaults */
	aic26_reg_write(&aic26->codec, AIC26_REG_RESET, 0xBB00);

	/* Power up CODEC */
	aic26_reg_write(&aic26->codec, AIC26_REG_POWER_CTRL, 0);

	/* Audio Control 3 (master mode, fsref rate) */
	reg = aic26_reg_read(&aic26->codec, AIC26_REG_AUDIO_CTRL3);
	reg &= ~0xf800;
	reg \|= 0x0800; /* set master mode */
	aic26_reg_write(&aic26->codec, AIC26_REG_AUDIO_CTRL3, reg);

	/* Fill register cache */
	for (i = 0; i < ARRAY_SIZE(aic26->reg_cache); i++)
	aic26_reg_read(&aic26->codec, i);

	/* Register the sysfs files for debugging */
	/* Create SysFS files */
	ret = device_create_file(&spi->dev, &dev_attr_keyclick);
	if (ret)
	dev_info(&spi->dev, "error creating sysfs files\n");

	#if defined(CONFIG_SND_SOC_OF_SIMPLE)
	/* Tell the of_soc helper about this codec */
	of_snd_soc_register_codec(&aic26_soc_codec_dev, aic26, &aic26_dai,
	spi->dev.archdata.of_node);
	#endif

	dev_dbg(&spi->dev, "SPI device initialized\n");
	return 0;
	}

	static int aic26_spi_remove(struct spi_device *spi)
	{
	struct aic26 *aic26 = dev_get_drvdata(&spi->dev);

	snd_soc_unregister_dai(&aic26_dai);
	kfree(aic26);

	return 0;
	}

	static struct spi_driver aic26_spi = {
	.driver = {
	.name = "tlv320aic26",
	.owner = THIS_MODULE,
	},
	.probe = aic26_spi_probe,
	.remove = aic26_spi_remove,
	};

	static int __init aic26_init(void)
	{
	return spi_register_driver(&aic26_spi);
	}
	module_init(aic26_init);

	static void __exit aic26_exit(void)
	{
	spi_unregister_driver(&aic26_spi);
	}
	module_exit(aic26_exit);