linux-stable/sound/soc/codecs/ak4104.c
Daniel Mack e555317c08 ASoC: fix ak4104 register array access
Don't touch the variable 'reg' to construct the value for the actual SPI
transport. This variable is again used to access the driver's register
cache, and so random memory is overwritten.
Compute the value in-place instead.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: stable@kernel.org
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2010-03-03 19:19:36 +00:00

353 lines
8.3 KiB
C

/*
* 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;
/* only write to the hardware if value has changed */
if (cache[reg] != value) {
u8 tmp[2] = { (reg & AK4104_REG_MASK) | AK4104_WRITE, 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_8000_192000,
.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_write(&ak4104->codec, AK4104_REG_CONTROL1, val);
if (ret < 0)
return ret;
ak4104_codec = NULL;
kfree(ak4104);
return 0;
}
static int ak4104_probe(struct platform_device *pdev)
{
struct snd_soc_device *socdev = platform_get_drvdata(pdev);
struct snd_soc_codec *codec = ak4104_codec;
int ret;
/* Connect the codec to the socdev. snd_soc_new_pcms() needs this. */
socdev->card->codec = codec;
/* Register PCMs */
ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
if (ret < 0) {
dev_err(codec->dev, "failed to create pcms\n");
return ret;
}
return 0;
}
static int ak4104_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 soc_codec_device_ak4104 = {
.probe = ak4104_probe,
.remove = ak4104_remove
};
EXPORT_SYMBOL_GPL(soc_codec_device_ak4104);
static struct spi_driver ak4104_spi_driver = {
.driver = {
.name = DRV_NAME,
.owner = THIS_MODULE,
},
.probe = ak4104_spi_probe,
.remove = __devexit_p(ak4104_spi_remove),
};
static int __init ak4104_init(void)
{
pr_info("Asahi Kasei AK4104 ALSA SoC Codec Driver\n");
return spi_register_driver(&ak4104_spi_driver);
}
module_init(ak4104_init);
static void __exit ak4104_exit(void)
{
spi_unregister_driver(&ak4104_spi_driver);
}
module_exit(ak4104_exit);
MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
MODULE_DESCRIPTION("Asahi Kasei AK4104 ALSA SoC driver");
MODULE_LICENSE("GPL");