linux/drivers/base/property.c

443 lines
16 KiB
C
Raw Normal View History

/*
* property.c - Unified device property interface.
*
* Copyright (C) 2014, Intel Corporation
* Authors: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/property.h>
#include <linux/export.h>
#include <linux/acpi.h>
#include <linux/of.h>
/**
* device_property_present - check if a property of a device is present
* @dev: Device whose property is being checked
* @propname: Name of the property
*
* Check if property @propname is present in the device firmware description.
*/
bool device_property_present(struct device *dev, const char *propname)
{
if (IS_ENABLED(CONFIG_OF) && dev->of_node)
return of_property_read_bool(dev->of_node, propname);
return !acpi_dev_prop_get(ACPI_COMPANION(dev), propname, NULL);
}
EXPORT_SYMBOL_GPL(device_property_present);
/**
* fwnode_property_present - check if a property of a firmware node is present
* @fwnode: Firmware node whose property to check
* @propname: Name of the property
*/
bool fwnode_property_present(struct fwnode_handle *fwnode, const char *propname)
{
if (is_of_node(fwnode))
return of_property_read_bool(of_node(fwnode), propname);
else if (is_acpi_node(fwnode))
return !acpi_dev_prop_get(acpi_node(fwnode), propname, NULL);
return false;
}
EXPORT_SYMBOL_GPL(fwnode_property_present);
#define OF_DEV_PROP_READ_ARRAY(node, propname, type, val, nval) \
(val) ? of_property_read_##type##_array((node), (propname), (val), (nval)) \
: of_property_count_elems_of_size((node), (propname), sizeof(type))
#define DEV_PROP_READ_ARRAY(_dev_, _propname_, _type_, _proptype_, _val_, _nval_) \
IS_ENABLED(CONFIG_OF) && _dev_->of_node ? \
(OF_DEV_PROP_READ_ARRAY(_dev_->of_node, _propname_, _type_, \
_val_, _nval_)) : \
acpi_dev_prop_read(ACPI_COMPANION(_dev_), _propname_, \
_proptype_, _val_, _nval_)
/**
* device_property_read_u8_array - return a u8 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u8 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u8_array(struct device *dev, const char *propname,
u8 *val, size_t nval)
{
return DEV_PROP_READ_ARRAY(dev, propname, u8, DEV_PROP_U8, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u8_array);
/**
* device_property_read_u16_array - return a u16 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u16 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u16_array(struct device *dev, const char *propname,
u16 *val, size_t nval)
{
return DEV_PROP_READ_ARRAY(dev, propname, u16, DEV_PROP_U16, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u16_array);
/**
* device_property_read_u32_array - return a u32 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u32 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u32_array(struct device *dev, const char *propname,
u32 *val, size_t nval)
{
return DEV_PROP_READ_ARRAY(dev, propname, u32, DEV_PROP_U32, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u32_array);
/**
* device_property_read_u64_array - return a u64 array property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of u64 properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_u64_array(struct device *dev, const char *propname,
u64 *val, size_t nval)
{
return DEV_PROP_READ_ARRAY(dev, propname, u64, DEV_PROP_U64, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_u64_array);
/**
* device_property_read_string_array - return a string array property of device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Function reads an array of string properties with @propname from the device
* firmware description and stores them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property is not an array of strings,
* %-EOVERFLOW if the size of the property is not as expected.
*/
int device_property_read_string_array(struct device *dev, const char *propname,
const char **val, size_t nval)
{
return IS_ENABLED(CONFIG_OF) && dev->of_node ?
(val ? of_property_read_string_array(dev->of_node, propname, val, nval)
: of_property_count_strings(dev->of_node, propname)) :
acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
DEV_PROP_STRING, val, nval);
}
EXPORT_SYMBOL_GPL(device_property_read_string_array);
/**
* device_property_read_string - return a string property of a device
* @dev: Device to get the property of
* @propname: Name of the property
* @val: The value is stored here
*
* Function reads property @propname from the device firmware description and
* stores the value into @val if found. The value is checked to be a string.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property type is not a string.
*/
int device_property_read_string(struct device *dev, const char *propname,
const char **val)
{
return IS_ENABLED(CONFIG_OF) && dev->of_node ?
of_property_read_string(dev->of_node, propname, val) :
acpi_dev_prop_read(ACPI_COMPANION(dev), propname,
DEV_PROP_STRING, val, 1);
}
EXPORT_SYMBOL_GPL(device_property_read_string);
#define FWNODE_PROP_READ_ARRAY(_fwnode_, _propname_, _type_, _proptype_, _val_, _nval_) \
({ \
int _ret_; \
if (is_of_node(_fwnode_)) \
_ret_ = OF_DEV_PROP_READ_ARRAY(of_node(_fwnode_), _propname_, \
_type_, _val_, _nval_); \
else if (is_acpi_node(_fwnode_)) \
_ret_ = acpi_dev_prop_read(acpi_node(_fwnode_), _propname_, \
_proptype_, _val_, _nval_); \
else \
_ret_ = -ENXIO; \
_ret_; \
})
/**
* fwnode_property_read_u8_array - return a u8 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u8 properties with @propname from @fwnode and stores them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u8_array(struct fwnode_handle *fwnode,
const char *propname, u8 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u8, DEV_PROP_U8,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u8_array);
/**
* fwnode_property_read_u16_array - return a u16 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u16 properties with @propname from @fwnode and store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u16_array(struct fwnode_handle *fwnode,
const char *propname, u16 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u16, DEV_PROP_U16,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u16_array);
/**
* fwnode_property_read_u32_array - return a u32 array property of firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u32 properties with @propname from @fwnode store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u32_array(struct fwnode_handle *fwnode,
const char *propname, u32 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u32, DEV_PROP_U32,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u32_array);
/**
* fwnode_property_read_u64_array - return a u64 array property firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an array of u64 properties with @propname from @fwnode and store them to
* @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of numbers,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_u64_array(struct fwnode_handle *fwnode,
const char *propname, u64 *val, size_t nval)
{
return FWNODE_PROP_READ_ARRAY(fwnode, propname, u64, DEV_PROP_U64,
val, nval);
}
EXPORT_SYMBOL_GPL(fwnode_property_read_u64_array);
/**
* fwnode_property_read_string_array - return string array property of a node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The values are stored here or %NULL to return the number of values
* @nval: Size of the @val array
*
* Read an string list property @propname from the given firmware node and store
* them to @val if found.
*
* Return: number of values if @val was %NULL,
* %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO if the property is not an array of strings,
* %-EOVERFLOW if the size of the property is not as expected,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_string_array(struct fwnode_handle *fwnode,
const char *propname, const char **val,
size_t nval)
{
if (is_of_node(fwnode))
return of_property_read_string_array(of_node(fwnode), propname,
val, nval);
else if (is_acpi_node(fwnode))
return acpi_dev_prop_read(acpi_node(fwnode), propname,
DEV_PROP_STRING, val, nval);
return -ENXIO;
}
EXPORT_SYMBOL_GPL(fwnode_property_read_string_array);
/**
* fwnode_property_read_string - return a string property of a firmware node
* @fwnode: Firmware node to get the property of
* @propname: Name of the property
* @val: The value is stored here
*
* Read property @propname from the given firmware node and store the value into
* @val if found. The value is checked to be a string.
*
* Return: %0 if the property was found (success),
* %-EINVAL if given arguments are not valid,
* %-ENODATA if the property does not have a value,
* %-EPROTO or %-EILSEQ if the property is not a string,
* %-ENXIO if no suitable firmware interface is present.
*/
int fwnode_property_read_string(struct fwnode_handle *fwnode,
const char *propname, const char **val)
{
if (is_of_node(fwnode))
return of_property_read_string(of_node(fwnode),propname, val);
else if (is_acpi_node(fwnode))
return acpi_dev_prop_read(acpi_node(fwnode), propname,
DEV_PROP_STRING, val, 1);
return -ENXIO;
}
EXPORT_SYMBOL_GPL(fwnode_property_read_string);
/**
* device_get_next_child_node - Return the next child node handle for a device
* @dev: Device to find the next child node for.
* @child: Handle to one of the device's child nodes or a null handle.
*/
struct fwnode_handle *device_get_next_child_node(struct device *dev,
struct fwnode_handle *child)
{
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
struct device_node *node;
node = of_get_next_available_child(dev->of_node, of_node(child));
if (node)
return &node->fwnode;
} else if (IS_ENABLED(CONFIG_ACPI)) {
struct acpi_device *node;
node = acpi_get_next_child(dev, acpi_node(child));
if (node)
return acpi_fwnode_handle(node);
}
return NULL;
}
EXPORT_SYMBOL_GPL(device_get_next_child_node);
/**
* fwnode_handle_put - Drop reference to a device node
* @fwnode: Pointer to the device node to drop the reference to.
*
* This has to be used when terminating device_for_each_child_node() iteration
* with break or return to prevent stale device node references from being left
* behind.
*/
void fwnode_handle_put(struct fwnode_handle *fwnode)
{
if (is_of_node(fwnode))
of_node_put(of_node(fwnode));
}
EXPORT_SYMBOL_GPL(fwnode_handle_put);
/**
* device_get_child_node_count - return the number of child nodes for device
* @dev: Device to cound the child nodes for
*/
unsigned int device_get_child_node_count(struct device *dev)
{
struct fwnode_handle *child;
unsigned int count = 0;
device_for_each_child_node(dev, child)
count++;
return count;
}
EXPORT_SYMBOL_GPL(device_get_child_node_count);