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linux-sg2042/sound/soc/codecs/ad1938.c

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/*
* File: sound/soc/codecs/ad1938.c
* Author: Barry Song <Barry.Song@analog.com>
*
* Created: June 04 2009
* Description: Driver for AD1938 sound chip
*
* Modified:
* Copyright 2009 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <sound/soc.h>
#include <sound/tlv.h>
#include <sound/soc-dapm.h>
#include <linux/spi/spi.h>
#include "ad1938.h"
/* codec private data */
struct ad1938_priv {
struct snd_soc_codec codec;
u8 reg_cache[AD1938_NUM_REGS];
};
static struct snd_soc_codec *ad1938_codec;
struct snd_soc_codec_device soc_codec_dev_ad1938;
static int ad1938_register(struct ad1938_priv *ad1938);
static void ad1938_unregister(struct ad1938_priv *ad1938);
/*
* AD1938 volume/mute/de-emphasis etc. controls
*/
static const char *ad1938_deemp[] = {"None", "48kHz", "44.1kHz", "32kHz"};
static const struct soc_enum ad1938_deemp_enum =
SOC_ENUM_SINGLE(AD1938_DAC_CTRL2, 1, 4, ad1938_deemp);
static const struct snd_kcontrol_new ad1938_snd_controls[] = {
/* DAC volume control */
SOC_DOUBLE_R("DAC1 Volume", AD1938_DAC_L1_VOL,
AD1938_DAC_R1_VOL, 0, 0xFF, 1),
SOC_DOUBLE_R("DAC2 Volume", AD1938_DAC_L2_VOL,
AD1938_DAC_R2_VOL, 0, 0xFF, 1),
SOC_DOUBLE_R("DAC3 Volume", AD1938_DAC_L3_VOL,
AD1938_DAC_R3_VOL, 0, 0xFF, 1),
SOC_DOUBLE_R("DAC4 Volume", AD1938_DAC_L4_VOL,
AD1938_DAC_R4_VOL, 0, 0xFF, 1),
/* ADC switch control */
SOC_DOUBLE("ADC1 Switch", AD1938_ADC_CTRL0, AD1938_ADCL1_MUTE,
AD1938_ADCR1_MUTE, 1, 1),
SOC_DOUBLE("ADC2 Switch", AD1938_ADC_CTRL0, AD1938_ADCL2_MUTE,
AD1938_ADCR2_MUTE, 1, 1),
/* DAC switch control */
SOC_DOUBLE("DAC1 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL1_MUTE,
AD1938_DACR1_MUTE, 1, 1),
SOC_DOUBLE("DAC2 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL2_MUTE,
AD1938_DACR2_MUTE, 1, 1),
SOC_DOUBLE("DAC3 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL3_MUTE,
AD1938_DACR3_MUTE, 1, 1),
SOC_DOUBLE("DAC4 Switch", AD1938_DAC_CHNL_MUTE, AD1938_DACL4_MUTE,
AD1938_DACR4_MUTE, 1, 1),
/* ADC high-pass filter */
SOC_SINGLE("ADC High Pass Filter Switch", AD1938_ADC_CTRL0,
AD1938_ADC_HIGHPASS_FILTER, 1, 0),
/* DAC de-emphasis */
SOC_ENUM("Playback Deemphasis", ad1938_deemp_enum),
};
static const struct snd_soc_dapm_widget ad1938_dapm_widgets[] = {
SND_SOC_DAPM_DAC("DAC", "Playback", AD1938_DAC_CTRL0, 0, 1),
SND_SOC_DAPM_ADC("ADC", "Capture", SND_SOC_NOPM, 0, 0),
SND_SOC_DAPM_SUPPLY("ADC_PWR", AD1938_ADC_CTRL0, 0, 1, NULL, 0),
SND_SOC_DAPM_OUTPUT("DAC1OUT"),
SND_SOC_DAPM_OUTPUT("DAC2OUT"),
SND_SOC_DAPM_OUTPUT("DAC3OUT"),
SND_SOC_DAPM_OUTPUT("DAC4OUT"),
SND_SOC_DAPM_INPUT("ADC1IN"),
SND_SOC_DAPM_INPUT("ADC2IN"),
};
static const struct snd_soc_dapm_route audio_paths[] = {
{ "DAC", NULL, "ADC_PWR" },
{ "ADC", NULL, "ADC_PWR" },
{ "DAC1OUT", "DAC1 Switch", "DAC" },
{ "DAC2OUT", "DAC2 Switch", "DAC" },
{ "DAC3OUT", "DAC3 Switch", "DAC" },
{ "DAC4OUT", "DAC4 Switch", "DAC" },
{ "ADC", "ADC1 Switch", "ADC1IN" },
{ "ADC", "ADC2 Switch", "ADC2IN" },
};
/*
* DAI ops entries
*/
static int ad1938_mute(struct snd_soc_dai *dai, int mute)
{
struct snd_soc_codec *codec = dai->codec;
int reg;
reg = codec->read(codec, AD1938_DAC_CTRL2);
reg = (mute > 0) ? reg | AD1938_DAC_MASTER_MUTE : reg &
(~AD1938_DAC_MASTER_MUTE);
codec->write(codec, AD1938_DAC_CTRL2, reg);
return 0;
}
static inline int ad1938_pll_powerctrl(struct snd_soc_codec *codec, int cmd)
{
int reg = codec->read(codec, AD1938_PLL_CLK_CTRL0);
reg = (cmd > 0) ? reg & (~AD1938_PLL_POWERDOWN) : reg |
AD1938_PLL_POWERDOWN;
codec->write(codec, AD1938_PLL_CLK_CTRL0, reg);
return 0;
}
static int ad1938_set_tdm_slot(struct snd_soc_dai *dai, unsigned int tx_mask,
unsigned int mask, int slots, int width)
{
struct snd_soc_codec *codec = dai->codec;
int dac_reg = codec->read(codec, AD1938_DAC_CTRL1);
int adc_reg = codec->read(codec, AD1938_ADC_CTRL2);
dac_reg &= ~AD1938_DAC_CHAN_MASK;
adc_reg &= ~AD1938_ADC_CHAN_MASK;
switch (slots) {
case 2:
dac_reg |= AD1938_DAC_2_CHANNELS << AD1938_DAC_CHAN_SHFT;
adc_reg |= AD1938_ADC_2_CHANNELS << AD1938_ADC_CHAN_SHFT;
break;
case 4:
dac_reg |= AD1938_DAC_4_CHANNELS << AD1938_DAC_CHAN_SHFT;
adc_reg |= AD1938_ADC_4_CHANNELS << AD1938_ADC_CHAN_SHFT;
break;
case 8:
dac_reg |= AD1938_DAC_8_CHANNELS << AD1938_DAC_CHAN_SHFT;
adc_reg |= AD1938_ADC_8_CHANNELS << AD1938_ADC_CHAN_SHFT;
break;
case 16:
dac_reg |= AD1938_DAC_16_CHANNELS << AD1938_DAC_CHAN_SHFT;
adc_reg |= AD1938_ADC_16_CHANNELS << AD1938_ADC_CHAN_SHFT;
break;
default:
return -EINVAL;
}
codec->write(codec, AD1938_DAC_CTRL1, dac_reg);
codec->write(codec, AD1938_ADC_CTRL2, adc_reg);
return 0;
}
static int ad1938_set_dai_fmt(struct snd_soc_dai *codec_dai,
unsigned int fmt)
{
struct snd_soc_codec *codec = codec_dai->codec;
int adc_reg, dac_reg;
adc_reg = codec->read(codec, AD1938_ADC_CTRL2);
dac_reg = codec->read(codec, AD1938_DAC_CTRL1);
/* At present, the driver only support AUX ADC mode(SND_SOC_DAIFMT_I2S
* with TDM) and ADC&DAC TDM mode(SND_SOC_DAIFMT_DSP_A)
*/
switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_I2S:
adc_reg &= ~AD1938_ADC_SERFMT_MASK;
adc_reg |= AD1938_ADC_SERFMT_TDM;
break;
case SND_SOC_DAIFMT_DSP_A:
adc_reg &= ~AD1938_ADC_SERFMT_MASK;
adc_reg |= AD1938_ADC_SERFMT_AUX;
break;
default:
return -EINVAL;
}
switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
case SND_SOC_DAIFMT_NB_NF: /* normal bit clock + frame */
adc_reg &= ~AD1938_ADC_LEFT_HIGH;
adc_reg &= ~AD1938_ADC_BCLK_INV;
dac_reg &= ~AD1938_DAC_LEFT_HIGH;
dac_reg &= ~AD1938_DAC_BCLK_INV;
break;
case SND_SOC_DAIFMT_NB_IF: /* normal bclk + invert frm */
adc_reg |= AD1938_ADC_LEFT_HIGH;
adc_reg &= ~AD1938_ADC_BCLK_INV;
dac_reg |= AD1938_DAC_LEFT_HIGH;
dac_reg &= ~AD1938_DAC_BCLK_INV;
break;
case SND_SOC_DAIFMT_IB_NF: /* invert bclk + normal frm */
adc_reg &= ~AD1938_ADC_LEFT_HIGH;
adc_reg |= AD1938_ADC_BCLK_INV;
dac_reg &= ~AD1938_DAC_LEFT_HIGH;
dac_reg |= AD1938_DAC_BCLK_INV;
break;
case SND_SOC_DAIFMT_IB_IF: /* invert bclk + frm */
adc_reg |= AD1938_ADC_LEFT_HIGH;
adc_reg |= AD1938_ADC_BCLK_INV;
dac_reg |= AD1938_DAC_LEFT_HIGH;
dac_reg |= AD1938_DAC_BCLK_INV;
break;
default:
return -EINVAL;
}
switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
case SND_SOC_DAIFMT_CBM_CFM: /* codec clk & frm master */
adc_reg |= AD1938_ADC_LCR_MASTER;
adc_reg |= AD1938_ADC_BCLK_MASTER;
dac_reg |= AD1938_DAC_LCR_MASTER;
dac_reg |= AD1938_DAC_BCLK_MASTER;
break;
case SND_SOC_DAIFMT_CBS_CFM: /* codec clk slave & frm master */
adc_reg |= AD1938_ADC_LCR_MASTER;
adc_reg &= ~AD1938_ADC_BCLK_MASTER;
dac_reg |= AD1938_DAC_LCR_MASTER;
dac_reg &= ~AD1938_DAC_BCLK_MASTER;
break;
case SND_SOC_DAIFMT_CBM_CFS: /* codec clk master & frame slave */
adc_reg &= ~AD1938_ADC_LCR_MASTER;
adc_reg |= AD1938_ADC_BCLK_MASTER;
dac_reg &= ~AD1938_DAC_LCR_MASTER;
dac_reg |= AD1938_DAC_BCLK_MASTER;
break;
case SND_SOC_DAIFMT_CBS_CFS: /* codec clk & frm slave */
adc_reg &= ~AD1938_ADC_LCR_MASTER;
adc_reg &= ~AD1938_ADC_BCLK_MASTER;
dac_reg &= ~AD1938_DAC_LCR_MASTER;
dac_reg &= ~AD1938_DAC_BCLK_MASTER;
break;
default:
return -EINVAL;
}
codec->write(codec, AD1938_ADC_CTRL2, adc_reg);
codec->write(codec, AD1938_DAC_CTRL1, dac_reg);
return 0;
}
static int ad1938_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
{
int word_len = 0, reg = 0;
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct snd_soc_device *socdev = rtd->socdev;
struct snd_soc_codec *codec = socdev->card->codec;
/* bit size */
switch (params_format(params)) {
case SNDRV_PCM_FORMAT_S16_LE:
word_len = 3;
break;
case SNDRV_PCM_FORMAT_S20_3LE:
word_len = 1;
break;
case SNDRV_PCM_FORMAT_S24_LE:
case SNDRV_PCM_FORMAT_S32_LE:
word_len = 0;
break;
}
reg = codec->read(codec, AD1938_DAC_CTRL2);
reg = (reg & (~AD1938_DAC_WORD_LEN_MASK)) | word_len;
codec->write(codec, AD1938_DAC_CTRL2, reg);
reg = codec->read(codec, AD1938_ADC_CTRL1);
reg = (reg & (~AD1938_ADC_WORD_LEN_MASK)) | word_len;
codec->write(codec, AD1938_ADC_CTRL1, reg);
return 0;
}
static int ad1938_set_bias_level(struct snd_soc_codec *codec,
enum snd_soc_bias_level level)
{
switch (level) {
case SND_SOC_BIAS_ON:
ad1938_pll_powerctrl(codec, 1);
break;
case SND_SOC_BIAS_PREPARE:
break;
case SND_SOC_BIAS_STANDBY:
case SND_SOC_BIAS_OFF:
ad1938_pll_powerctrl(codec, 0);
break;
}
codec->bias_level = level;
return 0;
}
/*
* interface to read/write ad1938 register
*/
#define AD1938_SPI_ADDR 0x4
#define AD1938_SPI_READ 0x1
#define AD1938_SPI_BUFLEN 3
/*
* write to the ad1938 register space
*/
static int ad1938_write_reg(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 *reg_cache = codec->reg_cache;
int ret = 0;
if (value != reg_cache[reg]) {
uint8_t buf[AD1938_SPI_BUFLEN];
struct spi_transfer t = {
.tx_buf = buf,
.len = AD1938_SPI_BUFLEN,
};
struct spi_message m;
buf[0] = AD1938_SPI_ADDR << 1;
buf[1] = reg;
buf[2] = value;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
ret = spi_sync(codec->control_data, &m);
if (ret == 0)
reg_cache[reg] = value;
}
return ret;
}
/*
* read from the ad1938 register space cache
*/
static unsigned int ad1938_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];
}
/*
* read from the ad1938 register space
*/
static unsigned int ad1938_read_reg(struct snd_soc_codec *codec,
unsigned int reg)
{
char w_buf[AD1938_SPI_BUFLEN];
char r_buf[AD1938_SPI_BUFLEN];
int ret;
struct spi_transfer t = {
.tx_buf = w_buf,
.rx_buf = r_buf,
.len = AD1938_SPI_BUFLEN,
};
struct spi_message m;
w_buf[0] = (AD1938_SPI_ADDR << 1) | AD1938_SPI_READ;
w_buf[1] = reg;
w_buf[2] = 0;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
ret = spi_sync(codec->control_data, &m);
if (ret == 0)
return r_buf[2];
else
return -EIO;
}
static int ad1938_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 = ad1938_read_reg(codec, i);
if (ret == -EIO) {
dev_err(&spi->dev, "AD1938 SPI read failure\n");
return ret;
}
reg_cache[i] = ret;
}
return 0;
}
static int __devinit ad1938_spi_probe(struct spi_device *spi)
{
struct snd_soc_codec *codec;
struct ad1938_priv *ad1938;
ad1938 = kzalloc(sizeof(struct ad1938_priv), GFP_KERNEL);
if (ad1938 == NULL)
return -ENOMEM;
codec = &ad1938->codec;
codec->control_data = spi;
codec->dev = &spi->dev;
dev_set_drvdata(&spi->dev, ad1938);
return ad1938_register(ad1938);
}
static int __devexit ad1938_spi_remove(struct spi_device *spi)
{
struct ad1938_priv *ad1938 = dev_get_drvdata(&spi->dev);
ad1938_unregister(ad1938);
return 0;
}
static struct spi_driver ad1938_spi_driver = {
.driver = {
.name = "ad1938",
.owner = THIS_MODULE,
},
.probe = ad1938_spi_probe,
.remove = __devexit_p(ad1938_spi_remove),
};
static struct snd_soc_dai_ops ad1938_dai_ops = {
.hw_params = ad1938_hw_params,
.digital_mute = ad1938_mute,
.set_tdm_slot = ad1938_set_tdm_slot,
.set_fmt = ad1938_set_dai_fmt,
};
/* codec DAI instance */
struct snd_soc_dai ad1938_dai = {
.name = "AD1938",
.playback = {
.stream_name = "Playback",
.channels_min = 2,
.channels_max = 8,
.rates = SNDRV_PCM_RATE_48000,
.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE,
},
.capture = {
.stream_name = "Capture",
.channels_min = 2,
.channels_max = 4,
.rates = SNDRV_PCM_RATE_48000,
.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S20_3LE | SNDRV_PCM_FMTBIT_S24_LE,
},
.ops = &ad1938_dai_ops,
};
EXPORT_SYMBOL_GPL(ad1938_dai);
static int ad1938_register(struct ad1938_priv *ad1938)
{
int ret;
struct snd_soc_codec *codec = &ad1938->codec;
if (ad1938_codec) {
dev_err(codec->dev, "Another ad1938 is registered\n");
return -EINVAL;
}
mutex_init(&codec->mutex);
INIT_LIST_HEAD(&codec->dapm_widgets);
INIT_LIST_HEAD(&codec->dapm_paths);
codec->private_data = ad1938;
codec->reg_cache = ad1938->reg_cache;
codec->reg_cache_size = AD1938_NUM_REGS;
codec->name = "AD1938";
codec->owner = THIS_MODULE;
codec->dai = &ad1938_dai;
codec->num_dai = 1;
codec->write = ad1938_write_reg;
codec->read = ad1938_read_reg_cache;
codec->set_bias_level = ad1938_set_bias_level;
INIT_LIST_HEAD(&codec->dapm_widgets);
INIT_LIST_HEAD(&codec->dapm_paths);
ad1938_dai.dev = codec->dev;
ad1938_codec = codec;
/* default setting for ad1938 */
/* unmute dac channels */
codec->write(codec, AD1938_DAC_CHNL_MUTE, 0x0);
/* de-emphasis: 48kHz, powedown dac */
codec->write(codec, AD1938_DAC_CTRL2, 0x1A);
/* powerdown dac, dac in tdm mode */
codec->write(codec, AD1938_DAC_CTRL0, 0x41);
/* high-pass filter enable */
codec->write(codec, AD1938_ADC_CTRL0, 0x3);
/* sata delay=1, adc aux mode */
codec->write(codec, AD1938_ADC_CTRL1, 0x43);
/* pll input: mclki/xi */
codec->write(codec, AD1938_PLL_CLK_CTRL0, 0x9D);
codec->write(codec, AD1938_PLL_CLK_CTRL1, 0x04);
ad1938_fill_cache(codec);
ret = snd_soc_register_codec(codec);
if (ret != 0) {
dev_err(codec->dev, "Failed to register codec: %d\n", ret);
kfree(ad1938);
return ret;
}
ret = snd_soc_register_dai(&ad1938_dai);
if (ret != 0) {
dev_err(codec->dev, "Failed to register DAI: %d\n", ret);
snd_soc_unregister_codec(codec);
kfree(ad1938);
return ret;
}
return 0;
}
static void ad1938_unregister(struct ad1938_priv *ad1938)
{
ad1938_set_bias_level(&ad1938->codec, SND_SOC_BIAS_OFF);
snd_soc_unregister_dai(&ad1938_dai);
snd_soc_unregister_codec(&ad1938->codec);
kfree(ad1938);
ad1938_codec = NULL;
}
static int ad1938_probe(struct platform_device *pdev)
{
struct snd_soc_device *socdev = platform_get_drvdata(pdev);
struct snd_soc_codec *codec;
int ret = 0;
if (ad1938_codec == NULL) {
dev_err(&pdev->dev, "Codec device not registered\n");
return -ENODEV;
}
socdev->card->codec = ad1938_codec;
codec = ad1938_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: %d\n", ret);
goto pcm_err;
}
snd_soc_add_controls(codec, ad1938_snd_controls,
ARRAY_SIZE(ad1938_snd_controls));
snd_soc_dapm_new_controls(codec, ad1938_dapm_widgets,
ARRAY_SIZE(ad1938_dapm_widgets));
snd_soc_dapm_add_routes(codec, audio_paths, ARRAY_SIZE(audio_paths));
ad1938_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
pcm_err:
return ret;
}
/* power down chip */
static int ad1938_remove(struct platform_device *pdev)
{
struct snd_soc_device *socdev = platform_get_drvdata(pdev);
snd_soc_free_pcms(socdev);
snd_soc_dapm_free(socdev);
return 0;
}
#ifdef CONFIG_PM
static int ad1938_suspend(struct platform_device *pdev,
pm_message_t state)
{
struct snd_soc_device *socdev = platform_get_drvdata(pdev);
struct snd_soc_codec *codec = socdev->card->codec;
ad1938_set_bias_level(codec, SND_SOC_BIAS_OFF);
return 0;
}
static int ad1938_resume(struct platform_device *pdev)
{
struct snd_soc_device *socdev = platform_get_drvdata(pdev);
struct snd_soc_codec *codec = socdev->card->codec;
if (codec->suspend_bias_level == SND_SOC_BIAS_ON)
ad1938_set_bias_level(codec, SND_SOC_BIAS_ON);
return 0;
}
#else
#define ad1938_suspend NULL
#define ad1938_resume NULL
#endif
struct snd_soc_codec_device soc_codec_dev_ad1938 = {
.probe = ad1938_probe,
.remove = ad1938_remove,
.suspend = ad1938_suspend,
.resume = ad1938_resume,
};
EXPORT_SYMBOL_GPL(soc_codec_dev_ad1938);
static int __init ad1938_init(void)
{
int ret;
ret = spi_register_driver(&ad1938_spi_driver);
if (ret != 0) {
printk(KERN_ERR "Failed to register ad1938 SPI driver: %d\n",
ret);
}
return ret;
}
module_init(ad1938_init);
static void __exit ad1938_exit(void)
{
spi_unregister_driver(&ad1938_spi_driver);
}
module_exit(ad1938_exit);
MODULE_DESCRIPTION("ASoC ad1938 driver");
MODULE_AUTHOR("Barry Song ");
MODULE_LICENSE("GPL");
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