linux/sound/soc/soc-io.c
Lars-Peter Clausen e2c330b9b5 ASoC: Move IO abstraction to the component level
We currently have two very similar IO abstractions in ASoC, one for CODECs, the
other for platforms. Moving this to the component level will allow us to unify
those two. It will also enable us to move the standard kcontrol helpers as well
as DAPM support to the component level.

The new component level abstraction layer is primarily build around regmap.
There is a per component pointer for the regmap instance for the underlying
device. There are four new function snd_soc_component_read(),
snd_soc_component_write(), snd_soc_component_update_bits() and
snd_soc_component_update_bits_async(). They have the same signature as their
regmap counter-part and will internally forward the call one-to-one to regmap.
If the component it not using regmap it will fallback to using the custom IO
callbacks. This is done to be able to support drivers that haven't been
converted to regmap yet, but it is expected that this will eventually be removed
in the future once all component drivers have been converted to regmap.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
2014-04-22 13:23:35 +01:00

333 lines
8.7 KiB
C

/*
* soc-io.c -- ASoC register I/O helpers
*
* Copyright 2009-2011 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 <linux/regmap.h>
#include <linux/export.h>
#include <sound/soc.h>
#include <trace/events/asoc.h>
/**
* snd_soc_component_read() - Read register value
* @component: Component to read from
* @reg: Register to read
* @val: Pointer to where the read value is stored
*
* Return: 0 on success, a negative error code otherwise.
*/
int snd_soc_component_read(struct snd_soc_component *component,
unsigned int reg, unsigned int *val)
{
int ret;
if (component->regmap)
ret = regmap_read(component->regmap, reg, val);
else if (component->read)
ret = component->read(component, reg, val);
else
ret = -EIO;
dev_dbg(component->dev, "read %x => %x\n", reg, *val);
return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_component_read);
/**
* snd_soc_component_write() - Write register value
* @component: Component to write to
* @reg: Register to write
* @val: Value to write to the register
*
* Return: 0 on success, a negative error code otherwise.
*/
int snd_soc_component_write(struct snd_soc_component *component,
unsigned int reg, unsigned int val)
{
dev_dbg(component->dev, "write %x = %x\n", reg, val);
if (component->regmap)
return regmap_write(component->regmap, reg, val);
else if (component->write)
return component->write(component, reg, val);
else
return -EIO;
}
EXPORT_SYMBOL_GPL(snd_soc_component_write);
static int snd_soc_component_update_bits_legacy(
struct snd_soc_component *component, unsigned int reg,
unsigned int mask, unsigned int val, bool *change)
{
unsigned int old, new;
int ret;
if (!component->read || !component->write)
return -EIO;
mutex_lock(&component->io_mutex);
ret = component->read(component, reg, &old);
if (ret < 0)
goto out_unlock;
new = (old & ~mask) | (val & mask);
*change = old != new;
if (*change)
ret = component->write(component, reg, new);
out_unlock:
mutex_unlock(&component->io_mutex);
return ret;
}
/**
* snd_soc_component_update_bits() - Perform read/modify/write cycle
* @component: Component to update
* @reg: Register to update
* @mask: Mask that specifies which bits to update
* @val: New value for the bits specified by mask
*
* Return: 1 if the operation was successful and the value of the register
* changed, 0 if the operation was successful, but the value did not change.
* Returns a negative error code otherwise.
*/
int snd_soc_component_update_bits(struct snd_soc_component *component,
unsigned int reg, unsigned int mask, unsigned int val)
{
bool change;
int ret;
if (component->regmap)
ret = regmap_update_bits_check(component->regmap, reg, mask,
val, &change);
else
ret = snd_soc_component_update_bits_legacy(component, reg,
mask, val, &change);
if (ret < 0)
return ret;
return change;
}
EXPORT_SYMBOL_GPL(snd_soc_component_update_bits);
/**
* snd_soc_component_update_bits_async() - Perform asynchronous
* read/modify/write cycle
* @component: Component to update
* @reg: Register to update
* @mask: Mask that specifies which bits to update
* @val: New value for the bits specified by mask
*
* This function is similar to snd_soc_component_update_bits(), but the update
* operation is scheduled asynchronously. This means it may not be completed
* when the function returns. To make sure that all scheduled updates have been
* completed snd_soc_component_async_complete() must be called.
*
* Return: 1 if the operation was successful and the value of the register
* changed, 0 if the operation was successful, but the value did not change.
* Returns a negative error code otherwise.
*/
int snd_soc_component_update_bits_async(struct snd_soc_component *component,
unsigned int reg, unsigned int mask, unsigned int val)
{
bool change;
int ret;
if (component->regmap)
ret = regmap_update_bits_check_async(component->regmap, reg,
mask, val, &change);
else
ret = snd_soc_component_update_bits_legacy(component, reg,
mask, val, &change);
if (ret < 0)
return ret;
return change;
}
EXPORT_SYMBOL_GPL(snd_soc_component_update_bits_async);
/**
* snd_soc_component_async_complete() - Ensure asynchronous I/O has completed
* @component: Component for which to wait
*
* This function blocks until all asynchronous I/O which has previously been
* scheduled using snd_soc_component_update_bits_async() has completed.
*/
void snd_soc_component_async_complete(struct snd_soc_component *component)
{
if (component->regmap)
regmap_async_complete(component->regmap);
}
EXPORT_SYMBOL_GPL(snd_soc_component_async_complete);
/**
* snd_soc_component_test_bits - Test register for change
* @component: component
* @reg: Register to test
* @mask: Mask that specifies which bits to test
* @value: Value to test against
*
* Tests a register with a new value and checks if the new value is
* different from the old value.
*
* Return: 1 for change, otherwise 0.
*/
int snd_soc_component_test_bits(struct snd_soc_component *component,
unsigned int reg, unsigned int mask, unsigned int value)
{
unsigned int old, new;
int ret;
ret = snd_soc_component_read(component, reg, &old);
if (ret < 0)
return ret;
new = (old & ~mask) | value;
return old != new;
}
EXPORT_SYMBOL_GPL(snd_soc_component_test_bits);
unsigned int snd_soc_read(struct snd_soc_codec *codec, unsigned int reg)
{
unsigned int val;
int ret;
ret = snd_soc_component_read(&codec->component, reg, &val);
if (ret < 0)
return -1;
trace_snd_soc_reg_read(codec, reg, val);
return val;
}
EXPORT_SYMBOL_GPL(snd_soc_read);
int snd_soc_write(struct snd_soc_codec *codec, unsigned int reg,
unsigned int val)
{
trace_snd_soc_reg_write(codec, reg, val);
return snd_soc_component_write(&codec->component, reg, val);
}
EXPORT_SYMBOL_GPL(snd_soc_write);
/**
* snd_soc_update_bits - update codec register bits
* @codec: audio codec
* @reg: codec register
* @mask: register mask
* @value: new value
*
* Writes new register value.
*
* Returns 1 for change, 0 for no change, or negative error code.
*/
int snd_soc_update_bits(struct snd_soc_codec *codec, unsigned int reg,
unsigned int mask, unsigned int value)
{
return snd_soc_component_update_bits(&codec->component, reg, mask,
value);
}
EXPORT_SYMBOL_GPL(snd_soc_update_bits);
/**
* snd_soc_update_bits_locked - update codec register bits
* @codec: audio codec
* @reg: codec register
* @mask: register mask
* @value: new value
*
* Writes new register value, and takes the codec mutex.
*
* Returns 1 for change else 0.
*/
int snd_soc_update_bits_locked(struct snd_soc_codec *codec,
unsigned int reg, unsigned int mask,
unsigned int value)
{
return snd_soc_component_update_bits(&codec->component, reg, mask,
value);
}
EXPORT_SYMBOL_GPL(snd_soc_update_bits_locked);
/**
* snd_soc_test_bits - test register for change
* @codec: audio codec
* @reg: codec register
* @mask: register mask
* @value: new value
*
* Tests a register with a new value and checks if the new value is
* different from the old value.
*
* Returns 1 for change else 0.
*/
int snd_soc_test_bits(struct snd_soc_codec *codec, unsigned int reg,
unsigned int mask, unsigned int value)
{
return snd_soc_component_test_bits(&codec->component, reg, mask, value);
}
EXPORT_SYMBOL_GPL(snd_soc_test_bits);
int snd_soc_platform_read(struct snd_soc_platform *platform,
unsigned int reg)
{
unsigned int val;
int ret;
ret = snd_soc_component_read(&platform->component, reg, &val);
if (ret < 0)
return -1;
trace_snd_soc_preg_read(platform, reg, val);
return val;
}
EXPORT_SYMBOL_GPL(snd_soc_platform_read);
int snd_soc_platform_write(struct snd_soc_platform *platform,
unsigned int reg, unsigned int val)
{
trace_snd_soc_preg_write(platform, reg, val);
return snd_soc_component_write(&platform->component, reg, val);
}
EXPORT_SYMBOL_GPL(snd_soc_platform_write);
/**
* snd_soc_component_init_io() - Initialize regmap IO
*
* @component: component to initialize
* @regmap: regmap instance to use for IO operations
*
* Return: 0 on success, a negative error code otherwise
*/
int snd_soc_component_init_io(struct snd_soc_component *component,
struct regmap *regmap)
{
int ret;
if (!regmap)
return -EINVAL;
ret = regmap_get_val_bytes(regmap);
/* Errors are legitimate for non-integer byte
* multiples */
if (ret > 0)
component->val_bytes = ret;
component->regmap = regmap;
return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_component_init_io);