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/*
* AK4104 ALSA SoC (ASoC) driver
*
* Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <sound/core.h>
#include <sound/soc.h>
#include <sound/initval.h>
#include <linux/spi/spi.h>
#include <sound/asoundef.h>
#include "ak4104.h"
/* AK4104 registers addresses */
#define AK4104_REG_CONTROL1 0x00
#define AK4104_REG_RESERVED 0x01
#define AK4104_REG_CONTROL2 0x02
#define AK4104_REG_TX 0x03
#define AK4104_REG_CHN_STATUS(x) ((x) + 0x04)
#define AK4104_NUM_REGS 10
#define AK4104_REG_MASK 0x1f
#define AK4104_READ 0xc0
#define AK4104_WRITE 0xe0
#define AK4104_RESERVED_VAL 0x5b
/* Bit masks for AK4104 registers */
#define AK4104_CONTROL1_RSTN (1 << 0)
#define AK4104_CONTROL1_PW (1 << 1)
#define AK4104_CONTROL1_DIF0 (1 << 2)
#define AK4104_CONTROL1_DIF1 (1 << 3)
#define AK4104_CONTROL2_SEL0 (1 << 0)
#define AK4104_CONTROL2_SEL1 (1 << 1)
#define AK4104_CONTROL2_MODE (1 << 2)
#define AK4104_TX_TXE (1 << 0)
#define AK4104_TX_V (1 << 1)
#define DRV_NAME "ak4104"
struct ak4104_private {
struct snd_soc_codec codec;
u8 reg_cache[AK4104_NUM_REGS];
};
static int ak4104_fill_cache(struct snd_soc_codec *codec)
{
int i;
u8 *reg_cache = codec->reg_cache;
struct spi_device *spi = codec->control_data;
for (i = 0; i < codec->reg_cache_size; i++) {
int ret = spi_w8r8(spi, i | AK4104_READ);
if (ret < 0) {
dev_err(&spi->dev, "SPI write failure\n");
return ret;
}
reg_cache[i] = ret;
}
return 0;
}
static unsigned int ak4104_read_reg_cache(struct snd_soc_codec *codec,
unsigned int reg)
{
u8 *reg_cache = codec->reg_cache;
if (reg >= codec->reg_cache_size)
return -EINVAL;
return reg_cache[reg];
}
static int ak4104_spi_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 *cache = codec->reg_cache;
struct spi_device *spi = codec->control_data;
if (reg >= codec->reg_cache_size)
return -EINVAL;
reg &= AK4104_REG_MASK;
reg |= AK4104_WRITE;
/* only write to the hardware if value has changed */
if (cache[reg] != value) {
u8 tmp[2] = { reg, value };
if (spi_write(spi, tmp, sizeof(tmp))) {
dev_err(&spi->dev, "SPI write failed\n");
return -EIO;
}
cache[reg] = value;
}
return 0;
}
static int ak4104_set_dai_fmt(struct snd_soc_dai *codec_dai,
unsigned int format)
{
struct snd_soc_codec *codec = codec_dai->codec;
int val = 0;
val = ak4104_read_reg_cache(codec, AK4104_REG_CONTROL1);
if (val < 0)
return val;
val &= ~(AK4104_CONTROL1_DIF0 | AK4104_CONTROL1_DIF1);
/* set DAI format */
switch (format & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_RIGHT_J:
break;
case SND_SOC_DAIFMT_LEFT_J:
val |= AK4104_CONTROL1_DIF0;
break;
case SND_SOC_DAIFMT_I2S:
val |= AK4104_CONTROL1_DIF0 | AK4104_CONTROL1_DIF1;
break;
default:
dev_err(codec->dev, "invalid dai format\n");
return -EINVAL;
}
/* This device can only be slave */
if ((format & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBS_CFS)
return -EINVAL;
return ak4104_spi_write(codec, AK4104_REG_CONTROL1, val);
}
static int ak4104_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;
int val = 0;
/* set the IEC958 bits: consumer mode, no copyright bit */
val |= IEC958_AES0_CON_NOT_COPYRIGHT;
ak4104_spi_write(codec, AK4104_REG_CHN_STATUS(0), val);
val = 0;
switch (params_rate(params)) {
case 44100:
val |= IEC958_AES3_CON_FS_44100;
break;
case 48000:
val |= IEC958_AES3_CON_FS_48000;
break;
case 32000:
val |= IEC958_AES3_CON_FS_32000;
break;
default:
dev_err(codec->dev, "unsupported sampling rate\n");
return -EINVAL;
}
return ak4104_spi_write(codec, AK4104_REG_CHN_STATUS(3), val);
}
static struct snd_soc_dai_ops ak4101_dai_ops = {
.hw_params = ak4104_hw_params,
.set_fmt = ak4104_set_dai_fmt,
};
struct snd_soc_dai ak4104_dai = {
.name = DRV_NAME,
.playback = {
.stream_name = "Playback",
.channels_min = 2,
.channels_max = 2,
.rates = SNDRV_PCM_RATE_44100 |
SNDRV_PCM_RATE_48000 |
SNDRV_PCM_RATE_32000,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S24_3LE |
SNDRV_PCM_FMTBIT_S24_LE
},
.ops = &ak4101_dai_ops,
};
static struct snd_soc_codec *ak4104_codec;
static int ak4104_spi_probe(struct spi_device *spi)
{
struct snd_soc_codec *codec;
struct ak4104_private *ak4104;
int ret, val;
spi->bits_per_word = 8;
spi->mode = SPI_MODE_0;
ret = spi_setup(spi);
if (ret < 0)
return ret;
ak4104 = kzalloc(sizeof(struct ak4104_private), GFP_KERNEL);
if (!ak4104) {
dev_err(&spi->dev, "could not allocate codec\n");
return -ENOMEM;
}
codec = &ak4104->codec;
mutex_init(&codec->mutex);
INIT_LIST_HEAD(&codec->dapm_widgets);
INIT_LIST_HEAD(&codec->dapm_paths);
codec->dev = &spi->dev;
codec->name = DRV_NAME;
codec->owner = THIS_MODULE;
codec->dai = &ak4104_dai;
codec->num_dai = 1;
codec->private_data = ak4104;
codec->control_data = spi;
codec->reg_cache = ak4104->reg_cache;
codec->reg_cache_size = AK4104_NUM_REGS;
/* read all regs and fill the cache */
ret = ak4104_fill_cache(codec);
if (ret < 0) {
dev_err(&spi->dev, "failed to fill register cache\n");
return ret;
}
/* read the 'reserved' register - according to the datasheet, it
* should contain 0x5b. Not a good way to verify the presence of
* the device, but there is no hardware ID register. */
if (ak4104_read_reg_cache(codec, AK4104_REG_RESERVED) !=
AK4104_RESERVED_VAL) {
ret = -ENODEV;
goto error_free_codec;
}
/* set power-up and non-reset bits */
val = ak4104_read_reg_cache(codec, AK4104_REG_CONTROL1);
val |= AK4104_CONTROL1_PW | AK4104_CONTROL1_RSTN;
ret = ak4104_spi_write(codec, AK4104_REG_CONTROL1, val);
if (ret < 0)
goto error_free_codec;
/* enable transmitter */
val = ak4104_read_reg_cache(codec, AK4104_REG_TX);
val |= AK4104_TX_TXE;
ret = ak4104_spi_write(codec, AK4104_REG_TX, val);
if (ret < 0)
goto error_free_codec;
ak4104_codec = codec;
ret = snd_soc_register_dai(&ak4104_dai);
if (ret < 0) {
dev_err(&spi->dev, "failed to register DAI\n");
goto error_free_codec;
}
spi_set_drvdata(spi, ak4104);
dev_info(&spi->dev, "SPI device initialized\n");
return 0;
error_free_codec:
kfree(ak4104);
ak4104_dai.dev = NULL;
return ret;
}
static int __devexit ak4104_spi_remove(struct spi_device *spi)
{
int ret, val;
struct ak4104_private *ak4104 = spi_get_drvdata(spi);
val = ak4104_read_reg_cache(&ak4104->codec, AK4104_REG_CONTROL1);
if (val < 0)
return val;
/* clear power-up and non-reset bits */
val &= ~(AK4104_CONTROL1_PW | AK4104_CONTROL1_RSTN);
ret = ak4104_spi_wr
|