blob: 026cd5347e53af2d2f2c6ac943cf648d1019837f [file] [log] [blame]
/*
* 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>
/**
* 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->driver->read) {
*val = component->driver->read(component, reg);
ret = 0;
}
else
ret = -EIO;
return ret;
}
EXPORT_SYMBOL_GPL(snd_soc_component_read);
unsigned int snd_soc_component_read32(struct snd_soc_component *component,
unsigned int reg)
{
unsigned int val;
int ret;
ret = snd_soc_component_read(component, reg, &val);
if (ret < 0)
return -1;
return val;
}
EXPORT_SYMBOL_GPL(snd_soc_component_read32);
/**
* 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)
{
if (component->regmap)
return regmap_write(component->regmap, reg, val);
else if (component->driver->write)
return component->driver->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;
mutex_lock(&component->io_mutex);
ret = snd_soc_component_read(component, reg, &old);
if (ret < 0)
goto out_unlock;
new = (old & ~mask) | (val & mask);
*change = old != new;
if (*change)
ret = snd_soc_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);