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ASoC: cs4270: use the built-in register cache support

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Update the CS4270 driver to use ASoC's internal codec register cache feature.
This change allows ASoC to perform the low-level I2C operations necessary to
read the register cache.  Support is also added for initializing the register
cache with an array of known power-on default values.

The CS4270 driver was handling the register cache itself, but somwhere along
the conversion to multi-compaonent, this feature broke.

Signed-off-by: Timur Tabi <timur@freescale.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Timur Tabi 2011-01-10 13:28:32 -06:00 committed by Mark Brown
parent b60fc60cea
commit 11b8fca53a
1 changed files with 48 additions and 113 deletions
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161
sound/soc/codecs/cs4270.c
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@ -106,6 +106,21 @@
#define CS4270_MUTE_DAC_A 0x01
#define CS4270_MUTE_DAC_B 0x02
/* Power-on default values for the registers
*
* This array contains the power-on default values of the registers, with the
* exception of the "CHIPID" register (01h). The lower four bits of that
* register contain the hardware revision, so it is treated as volatile.
*
* Also note that on the CS4270, the first readable register is 1, but ASoC
* assumes the first register is 0. Therfore, the array must have an entry for
* register 0, but we use cs4270_reg_is_readable() to tell ASoC that it can't
* be read.
*/
static const u8 cs4270_default_reg_cache[CS4270_LASTREG + 1] = {
0x00, 0x00, 0x00, 0x30, 0x00, 0x60, 0x20, 0x00, 0x00
};
static const char *supply_names[] = {
"va", "vd", "vlc"
};
@ -178,6 +193,20 @@ static struct cs4270_mode_ratios cs4270_mode_ratios[] = {
/* The number of MCLK/LRCK ratios supported by the CS4270 */
#define NUM_MCLK_RATIOS ARRAY_SIZE(cs4270_mode_ratios)
static int cs4270_reg_is_readable(unsigned int reg)
{
return (reg >= CS4270_FIRSTREG) && (reg <= CS4270_LASTREG);
}
static int cs4270_reg_is_volatile(unsigned int reg)
{
/* Unreadable registers are considered volatile */
if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
return 1;
return reg == CS4270_CHIPID;
}
/**
* cs4270_set_dai_sysclk - determine the CS4270 samples rates.
* @codec_dai: the codec DAI
@ -262,97 +291,6 @@ static int cs4270_set_dai_fmt(struct snd_soc_dai *codec_dai,
return ret;
}
/**
* cs4270_fill_cache - pre-fill the CS4270 register cache.
* @codec: the codec for this CS4270
*
* This function fills in the CS4270 register cache by reading the register
* values from the hardware.
*
* This CS4270 registers are cached to avoid excessive I2C I/O operations.
* After the initial read to pre-fill the cache, the CS4270 never updates
* the register values, so we won't have a cache coherency problem.
*
* We use the auto-increment feature of the CS4270 to read all registers in
* one shot.
*/
static int cs4270_fill_cache(struct snd_soc_codec *codec)
{
u8 *cache = codec->reg_cache;
struct i2c_client *i2c_client = codec->control_data;
s32 length;
length = i2c_smbus_read_i2c_block_data(i2c_client,
CS4270_FIRSTREG | CS4270_I2C_INCR, CS4270_NUMREGS, cache);
if (length != CS4270_NUMREGS) {
dev_err(codec->dev, "i2c read failure, addr=0x%x\n",
i2c_client->addr);
return -EIO;
}
return 0;
}
/**
* cs4270_read_reg_cache - read from the CS4270 register cache.
* @codec: the codec for this CS4270
* @reg: the register to read
*
* This function returns the value for a given register. It reads only from
* the register cache, not the hardware itself.
*
* This CS4270 registers are cached to avoid excessive I2C I/O operations.
* After the initial read to pre-fill the cache, the CS4270 never updates
* the register values, so we won't have a cache coherency problem.
*/
static unsigned int cs4270_read_reg_cache(struct snd_soc_codec *codec,
unsigned int reg)
{
u8 *cache = codec->reg_cache;
if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
return -EIO;
return cache[reg - CS4270_FIRSTREG];
}
/**
* cs4270_i2c_write - write to a CS4270 register via the I2C bus.
* @codec: the codec for this CS4270
* @reg: the register to write
* @value: the value to write to the register
*
* This function writes the given value to the given CS4270 register, and
* also updates the register cache.
*
* Note that we don't use the hw_write function pointer of snd_soc_codec.
* That's because it's too clunky: the hw_write_t prototype does not match
* i2c_smbus_write_byte_data(), and it's just another layer of overhead.
*/
static int cs4270_i2c_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int value)
{
u8 *cache = codec->reg_cache;
if ((reg < CS4270_FIRSTREG) || (reg > CS4270_LASTREG))
return -EIO;
/* Only perform an I2C operation if the new value is different */
if (cache[reg - CS4270_FIRSTREG] != value) {
struct i2c_client *client = codec->control_data;
if (i2c_smbus_write_byte_data(client, reg, value)) {
dev_err(codec->dev, "i2c write failed\n");
return -EIO;
}
/* We've written to the hardware, so update the cache */
cache[reg - CS4270_FIRSTREG] = value;
}
return 0;
}
/**
* cs4270_hw_params - program the CS4270 with the given hardware parameters.
* @substream: the audio stream
@ -550,15 +488,16 @@ static struct snd_soc_dai_driver cs4270_dai = {
static int cs4270_probe(struct snd_soc_codec *codec)
{
struct cs4270_private *cs4270 = snd_soc_codec_get_drvdata(codec);
int i, ret, reg;
int i, ret;
codec->control_data = cs4270->control_data;
/* The I2C interface is set up, so pre-fill our register cache */
ret = cs4270_fill_cache(codec);
/* Tell ASoC what kind of I/O to use to read the registers. ASoC will
* then do the I2C transactions itself.
*/
ret = snd_soc_codec_set_cache_io(codec, 8, 8, cs4270->control_type);
if (ret < 0) {
dev_err(codec->dev, "failed to fill register cache\n");
dev_err(codec->dev, "failed to set cache I/O (ret=%i)\n", ret);
return ret;
}
@ -567,10 +506,7 @@ static int cs4270_probe(struct snd_soc_codec *codec)
* this feature disabled by default. An application (e.g. alsactl) can
* re-enabled it by using the controls.
*/
reg = cs4270_read_reg_cache(codec, CS4270_MUTE);
reg &= ~CS4270_MUTE_AUTO;
ret = cs4270_i2c_write(codec, CS4270_MUTE, reg);
ret = snd_soc_update_bits(codec, CS4270_MUTE, CS4270_MUTE_AUTO, 0);
if (ret < 0) {
dev_err(codec->dev, "i2c write failed\n");
return ret;
@ -581,10 +517,8 @@ static int cs4270_probe(struct snd_soc_codec *codec)
* playback has started. An application (e.g. alsactl) can
* re-enabled it by using the controls.
*/
reg = cs4270_read_reg_cache(codec, CS4270_TRANS);
reg &= ~(CS4270_TRANS_SOFT | CS4270_TRANS_ZERO);
ret = cs4270_i2c_write(codec, CS4270_TRANS, reg);
ret = snd_soc_update_bits(codec, CS4270_TRANS,
CS4270_TRANS_SOFT | CS4270_TRANS_ZERO, 0);
if (ret < 0) {
dev_err(codec->dev, "i2c write failed\n");
return ret;
@ -707,15 +641,16 @@ static int cs4270_soc_resume(struct snd_soc_codec *codec)
* Assign this variable to the codec_dev field of the machine driver's
* snd_soc_device structure.
*/
static struct snd_soc_codec_driver soc_codec_device_cs4270 = {
.probe = cs4270_probe,
.remove = cs4270_remove,
.suspend = cs4270_soc_suspend,
.resume = cs4270_soc_resume,
.read = cs4270_read_reg_cache,
.write = cs4270_i2c_write,
.reg_cache_size = CS4270_NUMREGS,
.reg_word_size = sizeof(u8),
static const struct snd_soc_codec_driver soc_codec_device_cs4270 = {
.probe = cs4270_probe,
.remove = cs4270_remove,
.suspend = cs4270_soc_suspend,
.resume = cs4270_soc_resume,
.volatile_register = cs4270_reg_is_volatile,
.readable_register = cs4270_reg_is_readable,
.reg_cache_size = CS4270_LASTREG + 1,
.reg_word_size = sizeof(u8),
.reg_cache_default = cs4270_default_reg_cache,
};
/**