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kernel-ark/sound/soc/soc-cache.c
Dimitris Papastamos 7a30a3db34 ASoC: soc-cache: Add support for flat register caching 
This patch introduces the new caching API and migrates the
old caching interface into the new one.  The flat register caching
technique does not use compression at all and it is equivalent to
the old caching technique.  One can still access codec->reg_cache
directly but this is not advised as that will not be portable
across different caching strategies.

None of the existing drivers need to be changed to adapt to this
caching technique.  There should be no noticeable overhead associated
with using the new caching API.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2010-11-11 15:58:41 +00:00

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/*
* soc-cache.c -- ASoC register cache helpers
*
* Copyright 2009 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* 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/i2c.h>
#include <linux/spi/spi.h>
#include <sound/soc.h>
static unsigned int snd_soc_4_12_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
static int snd_soc_4_12_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[2];
int ret;
data[0] = (reg << 4) | ((value >> 8) & 0x000f);
data[1] = value & 0x00ff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
ret = codec->hw_write(codec->control_data, data, 2);
if (ret == 2)
return 0;
if (ret < 0)
return ret;
else
return -EIO;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_4_12_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[2];
if (len <= 0)
return 0;
msg[0] = data[1];
msg[1] = data[0];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_4_12_spi_write NULL
#endif
static unsigned int snd_soc_7_9_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
static int snd_soc_7_9_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[2];
int ret;
data[0] = (reg << 1) | ((value >> 8) & 0x0001);
data[1] = value & 0x00ff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
ret = codec->hw_write(codec->control_data, data, 2);
if (ret == 2)
return 0;
if (ret < 0)
return ret;
else
return -EIO;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_7_9_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[2];
if (len <= 0)
return 0;
msg[0] = data[0];
msg[1] = data[1];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_7_9_spi_write NULL
#endif
static int snd_soc_8_8_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[2];
int ret;
reg &= 0xff;
data[0] = reg;
data[1] = value & 0xff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
if (codec->hw_write(codec->control_data, data, 2) == 2)
return 0;
else
return -EIO;
}
static unsigned int snd_soc_8_8_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
reg &= 0xff;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_8_8_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[2];
if (len <= 0)
return 0;
msg[0] = data[0];
msg[1] = data[1];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_8_8_spi_write NULL
#endif
static int snd_soc_8_16_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[3];
int ret;
data[0] = reg;
data[1] = (value >> 8) & 0xff;
data[2] = value & 0xff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
if (codec->hw_write(codec->control_data, data, 3) == 3)
return 0;
else
return -EIO;
}
static unsigned int snd_soc_8_16_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_8_16_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[3];
if (len <= 0)
return 0;
msg[0] = data[0];
msg[1] = data[1];
msg[2] = data[2];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_8_16_spi_write NULL
#endif
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
static unsigned int snd_soc_8_8_read_i2c(struct snd_soc_codec *codec,
unsigned int r)
{
struct i2c_msg xfer[2];
u8 reg = r;
u8 data;
int ret;
struct i2c_client *client = codec->control_data;
/* Write register */
xfer[0].addr = client->addr;
xfer[0].flags = 0;
xfer[0].len = 1;
xfer[0].buf = &reg;
/* Read data */
xfer[1].addr = client->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = 1;
xfer[1].buf = &data;
ret = i2c_transfer(client->adapter, xfer, 2);
if (ret != 2) {
dev_err(&client->dev, "i2c_transfer() returned %d\n", ret);
return 0;
}
return data;
}
#else
#define snd_soc_8_8_read_i2c NULL
#endif
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
static unsigned int snd_soc_8_16_read_i2c(struct snd_soc_codec *codec,
unsigned int r)
{
struct i2c_msg xfer[2];
u8 reg = r;
u16 data;
int ret;
struct i2c_client *client = codec->control_data;
/* Write register */
xfer[0].addr = client->addr;
xfer[0].flags = 0;
xfer[0].len = 1;
xfer[0].buf = &reg;
/* Read data */
xfer[1].addr = client->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = 2;
xfer[1].buf = (u8 *)&data;
ret = i2c_transfer(client->adapter, xfer, 2);
if (ret != 2) {
dev_err(&client->dev, "i2c_transfer() returned %d\n", ret);
return 0;
}
return (data >> 8) | ((data & 0xff) << 8);
}
#else
#define snd_soc_8_16_read_i2c NULL
#endif
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
static unsigned int snd_soc_16_8_read_i2c(struct snd_soc_codec *codec,
unsigned int r)
{
struct i2c_msg xfer[2];
u16 reg = r;
u8 data;
int ret;
struct i2c_client *client = codec->control_data;
/* Write register */
xfer[0].addr = client->addr;
xfer[0].flags = 0;
xfer[0].len = 2;
xfer[0].buf = (u8 *)&reg;
/* Read data */
xfer[1].addr = client->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = 1;
xfer[1].buf = &data;
ret = i2c_transfer(client->adapter, xfer, 2);
if (ret != 2) {
dev_err(&client->dev, "i2c_transfer() returned %d\n", ret);
return 0;
}
return data;
}
#else
#define snd_soc_16_8_read_i2c NULL
#endif
static unsigned int snd_soc_16_8_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
reg &= 0xff;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
static int snd_soc_16_8_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[3];
int ret;
data[0] = (reg >> 8) & 0xff;
data[1] = reg & 0xff;
data[2] = value;
reg &= 0xff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
ret = codec->hw_write(codec->control_data, data, 3);
if (ret == 3)
return 0;
if (ret < 0)
return ret;
else
return -EIO;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_16_8_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[3];
if (len <= 0)
return 0;
msg[0] = data[0];
msg[1] = data[1];
msg[2] = data[2];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_16_8_spi_write NULL
#endif
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
static unsigned int snd_soc_16_16_read_i2c(struct snd_soc_codec *codec,
unsigned int r)
{
struct i2c_msg xfer[2];
u16 reg = cpu_to_be16(r);
u16 data;
int ret;
struct i2c_client *client = codec->control_data;
/* Write register */
xfer[0].addr = client->addr;
xfer[0].flags = 0;
xfer[0].len = 2;
xfer[0].buf = (u8 *)&reg;
/* Read data */
xfer[1].addr = client->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = 2;
xfer[1].buf = (u8 *)&data;
ret = i2c_transfer(client->adapter, xfer, 2);
if (ret != 2) {
dev_err(&client->dev, "i2c_transfer() returned %d\n", ret);
return 0;
}
return be16_to_cpu(data);
}
#else
#define snd_soc_16_16_read_i2c NULL
#endif
static unsigned int snd_soc_16_16_read(struct snd_soc_codec *codec,
unsigned int reg)
{
int ret;
unsigned int val;
if (reg >= codec->driver->reg_cache_size ||
snd_soc_codec_volatile_register(codec, reg)) {
if (codec->cache_only)
return -1;
BUG_ON(!codec->hw_read);
return codec->hw_read(codec, reg);
}
ret = snd_soc_cache_read(codec, reg, &val);
if (ret < 0)
return -1;
return val;
}
static int snd_soc_16_16_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 data[4];
int ret;
data[0] = (reg >> 8) & 0xff;
data[1] = reg & 0xff;
data[2] = (value >> 8) & 0xff;
data[3] = value & 0xff;
if (!snd_soc_codec_volatile_register(codec, reg) &&
reg < codec->driver->reg_cache_size) {
ret = snd_soc_cache_write(codec, reg, value);
if (ret < 0)
return -1;
}
if (codec->cache_only) {
codec->cache_sync = 1;
return 0;
}
ret = codec->hw_write(codec->control_data, data, 4);
if (ret == 4)
return 0;
if (ret < 0)
return ret;
else
return -EIO;
}
#if defined(CONFIG_SPI_MASTER)
static int snd_soc_16_16_spi_write(void *control_data, const char *data,
int len)
{
struct spi_device *spi = control_data;
struct spi_transfer t;
struct spi_message m;
u8 msg[4];
if (len <= 0)
return 0;
msg[0] = data[0];
msg[1] = data[1];
msg[2] = data[2];
msg[3] = data[3];
spi_message_init(&m);
memset(&t, 0, (sizeof t));
t.tx_buf = &msg[0];
t.len = len;
spi_message_add_tail(&t, &m);
spi_sync(spi, &m);
return len;
}
#else
#define snd_soc_16_16_spi_write NULL
#endif
static struct {
int addr_bits;
int data_bits;
int (*write)(struct snd_soc_codec *codec, unsigned int, unsigned int);
int (*spi_write)(void *, const char *, int);
unsigned int (*read)(struct snd_soc_codec *, unsigned int);
unsigned int (*i2c_read)(struct snd_soc_codec *, unsigned int);
} io_types[] = {
{
.addr_bits = 4, .data_bits = 12,
.write = snd_soc_4_12_write, .read = snd_soc_4_12_read,
.spi_write = snd_soc_4_12_spi_write,
},
{
.addr_bits = 7, .data_bits = 9,
.write = snd_soc_7_9_write, .read = snd_soc_7_9_read,
.spi_write = snd_soc_7_9_spi_write,
},
{
.addr_bits = 8, .data_bits = 8,
.write = snd_soc_8_8_write, .read = snd_soc_8_8_read,
.i2c_read = snd_soc_8_8_read_i2c,
.spi_write = snd_soc_8_8_spi_write,
},
{
.addr_bits = 8, .data_bits = 16,
.write = snd_soc_8_16_write, .read = snd_soc_8_16_read,
.i2c_read = snd_soc_8_16_read_i2c,
.spi_write = snd_soc_8_16_spi_write,
},
{
.addr_bits = 16, .data_bits = 8,
.write = snd_soc_16_8_write, .read = snd_soc_16_8_read,
.i2c_read = snd_soc_16_8_read_i2c,
.spi_write = snd_soc_16_8_spi_write,
},
{
.addr_bits = 16, .data_bits = 16,
.write = snd_soc_16_16_write, .read = snd_soc_16_16_read,
.i2c_read = snd_soc_16_16_read_i2c,
.spi_write = snd_soc_16_16_spi_write,
},
};
/**
* snd_soc_codec_set_cache_io: Set up standard I/O functions.
*
* @codec: CODEC to configure.
* @type: Type of cache.
* @addr_bits: Number of bits of register address data.
* @data_bits: Number of bits of data per register.
* @control: Control bus used.
*
* Register formats are frequently shared between many I2C and SPI
* devices. In order to promote code reuse the ASoC core provides
* some standard implementations of CODEC read and write operations
* which can be set up using this function.
*
* The caller is responsible for allocating and initialising the
* actual cache.
*
* Note that at present this code cannot be used by CODECs with
* volatile registers.
*/
int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
int addr_bits, int data_bits,
enum snd_soc_control_type control)
{
int i;
for (i = 0; i < ARRAY_SIZE(io_types); i++)
if (io_types[i].addr_bits == addr_bits &&
io_types[i].data_bits == data_bits)
break;
if (i == ARRAY_SIZE(io_types)) {
printk(KERN_ERR
"No I/O functions for %d bit address %d bit data\n",
addr_bits, data_bits);
return -EINVAL;
}
codec->driver->write = io_types[i].write;
codec->driver->read = io_types[i].read;
switch (control) {
case SND_SOC_CUSTOM:
break;
case SND_SOC_I2C:
#if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
codec->hw_write = (hw_write_t)i2c_master_send;
#endif
if (io_types[i].i2c_read)
codec->hw_read = io_types[i].i2c_read;
codec->control_data = container_of(codec->dev,
struct i2c_client,
dev);
break;
case SND_SOC_SPI:
if (io_types[i].spi_write)
codec->hw_write = io_types[i].spi_write;
codec->control_data = container_of(codec->dev,
struct spi_device,
dev);
break;
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io);
static int snd_soc_flat_cache_sync(struct snd_soc_codec *codec)
{
int i;
struct snd_soc_codec_driver *codec_drv;
unsigned int val;
codec_drv = codec->driver;
for (i = 0; i < codec_drv->reg_cache_size; ++i) {
snd_soc_cache_read(codec, i, &val);
if (codec_drv->reg_cache_default) {
switch (codec_drv->reg_word_size) {
case 1: {
const u8 *cache;
cache = codec_drv->reg_cache_default;
if (cache[i] == val)
continue;
}
break;
case 2: {
const u16 *cache;
cache = codec_drv->reg_cache_default;
if (cache[i] == val)
continue;
}
break;
default:
BUG();
}
}
snd_soc_write(codec, i, val);
dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
i, val);
}
return 0;
}
static int snd_soc_flat_cache_write(struct snd_soc_codec *codec,
unsigned int reg, unsigned int value)
{
switch (codec->driver->reg_word_size) {
case 1: {
u8 *cache;
cache = codec->reg_cache;
cache[reg] = value;
}
break;
case 2: {
u16 *cache;
cache = codec->reg_cache;
cache[reg] = value;
}
break;
default:
BUG();
}
return 0;
}
static int snd_soc_flat_cache_read(struct snd_soc_codec *codec,
unsigned int reg, unsigned int *value)
{
switch (codec->driver->reg_word_size) {
case 1: {
u8 *cache;
cache = codec->reg_cache;
*value = cache[reg];
}
break;
case 2: {
u16 *cache;
cache = codec->reg_cache;
*value = cache[reg];
}
break;
default:
BUG();
}
return 0;
}
static int snd_soc_flat_cache_exit(struct snd_soc_codec *codec)
{
if (!codec->reg_cache)
return 0;
kfree(codec->reg_cache);
codec->reg_cache = NULL;
return 0;
}
static int snd_soc_flat_cache_init(struct snd_soc_codec *codec)
{
struct snd_soc_codec_driver *codec_drv;
size_t reg_size;
codec_drv = codec->driver;
reg_size = codec_drv->reg_cache_size * codec_drv->reg_word_size;
if (codec_drv->reg_cache_default)
codec->reg_cache = kmemdup(codec_drv->reg_cache_default,
reg_size, GFP_KERNEL);
else
codec->reg_cache = kzalloc(reg_size, GFP_KERNEL);
if (!codec->reg_cache)
return -ENOMEM;
return 0;
}
/* an array of all supported compression types */
static const struct snd_soc_cache_ops cache_types[] = {
{
.id = SND_SOC_NO_COMPRESSION,
.init = snd_soc_flat_cache_init,
.exit = snd_soc_flat_cache_exit,
.read = snd_soc_flat_cache_read,
.write = snd_soc_flat_cache_write,
.sync = snd_soc_flat_cache_sync
}
};
int snd_soc_cache_init(struct snd_soc_codec *codec)
{
int i;
for (i = 0; i < ARRAY_SIZE(cache_types); ++i)
if (cache_types[i].id == codec->driver->compress_type)
break;
if (i == ARRAY_SIZE(cache_types)) {
dev_err(codec->dev, "Could not match compress type: %d\n",
codec->driver->compress_type);
return -EINVAL;
}
mutex_init(&codec->cache_rw_mutex);
codec->cache_ops = &cache_types[i];
if (codec->cache_ops->init)
return codec->cache_ops->init(codec);
return -EINVAL;
}
/*
* NOTE: keep in mind that this function might be called
* multiple times.
*/
int snd_soc_cache_exit(struct snd_soc_codec *codec)
{
if (codec->cache_ops && codec->cache_ops->exit)
return codec->cache_ops->exit(codec);
return -EINVAL;
}
/**
* snd_soc_cache_read: Fetch the value of a given register from the cache.
*
* @codec: CODEC to configure.
* @reg: The register index.
* @value: The value to be returned.
*/
int snd_soc_cache_read(struct snd_soc_codec *codec,
unsigned int reg, unsigned int *value)
{
int ret;
mutex_lock(&codec->cache_rw_mutex);
if (value && codec->cache_ops && codec->cache_ops->read) {
ret = codec->cache_ops->read(codec, reg, value);
mutex_unlock(&codec->cache_rw_mutex);
return ret;
}
mutex_unlock(&codec->cache_rw_mutex);
return -EINVAL;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_read);
/**
* snd_soc_cache_write: Set the value of a given register in the cache.
*
* @codec: CODEC to configure.
* @reg: The register index.
* @value: The new register value.
*/
int snd_soc_cache_write(struct snd_soc_codec *codec,
unsigned int reg, unsigned int value)
{
int ret;
mutex_lock(&codec->cache_rw_mutex);
if (codec->cache_ops && codec->cache_ops->write) {
ret = codec->cache_ops->write(codec, reg, value);
mutex_unlock(&codec->cache_rw_mutex);
return ret;
}
mutex_unlock(&codec->cache_rw_mutex);
return -EINVAL;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_write);
/**
* snd_soc_cache_sync: Sync the register cache with the hardware.
*
* @codec: CODEC to configure.
*
* Any registers that should not be synced should be marked as
* volatile. In general drivers can choose not to use the provided
* syncing functionality if they so require.
*/
int snd_soc_cache_sync(struct snd_soc_codec *codec)
{
int ret;
if (!codec->cache_sync) {
return 0;
}
if (codec->cache_ops && codec->cache_ops->sync) {
ret = codec->cache_ops->sync(codec);
if (!ret)
codec->cache_sync = 0;
return ret;
}
return -EINVAL;
}
EXPORT_SYMBOL_GPL(snd_soc_cache_sync);
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