linux-stable/include/linux/property.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* property.h - 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>
*/
#ifndef _LINUX_PROPERTY_H_
#define _LINUX_PROPERTY_H_
#include <linux/bits.h>
#include <linux/fwnode.h>
#include <linux/types.h>
struct device;
struct net_device;
enum dev_prop_type {
DEV_PROP_U8,
DEV_PROP_U16,
DEV_PROP_U32,
DEV_PROP_U64,
DEV_PROP_STRING,
DEV_PROP_REF,
};
enum dev_dma_attr {
DEV_DMA_NOT_SUPPORTED,
DEV_DMA_NON_COHERENT,
DEV_DMA_COHERENT,
};
struct fwnode_handle *dev_fwnode(struct device *dev);
bool device_property_present(struct device *dev, const char *propname);
int device_property_read_u8_array(struct device *dev, const char *propname,
u8 *val, size_t nval);
int device_property_read_u16_array(struct device *dev, const char *propname,
u16 *val, size_t nval);
int device_property_read_u32_array(struct device *dev, const char *propname,
u32 *val, size_t nval);
int device_property_read_u64_array(struct device *dev, const char *propname,
u64 *val, size_t nval);
int device_property_read_string_array(struct device *dev, const char *propname,
const char **val, size_t nval);
int device_property_read_string(struct device *dev, const char *propname,
const char **val);
int device_property_match_string(struct device *dev,
const char *propname, const char *string);
bool fwnode_device_is_available(const struct fwnode_handle *fwnode);
bool fwnode_property_present(const struct fwnode_handle *fwnode,
const char *propname);
int fwnode_property_read_u8_array(const struct fwnode_handle *fwnode,
const char *propname, u8 *val,
size_t nval);
int fwnode_property_read_u16_array(const struct fwnode_handle *fwnode,
const char *propname, u16 *val,
size_t nval);
int fwnode_property_read_u32_array(const struct fwnode_handle *fwnode,
const char *propname, u32 *val,
size_t nval);
int fwnode_property_read_u64_array(const struct fwnode_handle *fwnode,
const char *propname, u64 *val,
size_t nval);
int fwnode_property_read_string_array(const struct fwnode_handle *fwnode,
const char *propname, const char **val,
size_t nval);
int fwnode_property_read_string(const struct fwnode_handle *fwnode,
const char *propname, const char **val);
int fwnode_property_match_string(const struct fwnode_handle *fwnode,
const char *propname, const char *string);
int fwnode_property_get_reference_args(const struct fwnode_handle *fwnode,
const char *prop, const char *nargs_prop,
unsigned int nargs, unsigned int index,
struct fwnode_reference_args *args);
struct fwnode_handle *fwnode_find_reference(const struct fwnode_handle *fwnode,
const char *name,
unsigned int index);
const char *fwnode_get_name(const struct fwnode_handle *fwnode);
const char *fwnode_get_name_prefix(const struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_get_parent(const struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_get_next_parent(
struct fwnode_handle *fwnode);
struct device *fwnode_get_next_parent_dev(struct fwnode_handle *fwnode);
unsigned int fwnode_count_parents(const struct fwnode_handle *fwn);
struct fwnode_handle *fwnode_get_nth_parent(struct fwnode_handle *fwn,
unsigned int depth);
bool fwnode_is_ancestor_of(struct fwnode_handle *test_ancestor,
struct fwnode_handle *test_child);
struct fwnode_handle *fwnode_get_next_child_node(
const struct fwnode_handle *fwnode, struct fwnode_handle *child);
struct fwnode_handle *fwnode_get_next_available_child_node(
const struct fwnode_handle *fwnode, struct fwnode_handle *child);
#define fwnode_for_each_child_node(fwnode, child) \
for (child = fwnode_get_next_child_node(fwnode, NULL); child; \
child = fwnode_get_next_child_node(fwnode, child))
#define fwnode_for_each_available_child_node(fwnode, child) \
for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\
child = fwnode_get_next_available_child_node(fwnode, child))
struct fwnode_handle *device_get_next_child_node(
struct device *dev, struct fwnode_handle *child);
#define device_for_each_child_node(dev, child) \
for (child = device_get_next_child_node(dev, NULL); child; \
child = device_get_next_child_node(dev, child))
struct fwnode_handle *fwnode_get_named_child_node(
const struct fwnode_handle *fwnode, const char *childname);
struct fwnode_handle *device_get_named_child_node(struct device *dev,
const char *childname);
struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode);
void fwnode_handle_put(struct fwnode_handle *fwnode);
int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
void __iomem *fwnode_iomap(struct fwnode_handle *fwnode, int index);
unsigned int device_get_child_node_count(struct device *dev);
static inline bool device_property_read_bool(struct device *dev,
const char *propname)
{
return device_property_present(dev, propname);
}
static inline int device_property_read_u8(struct device *dev,
const char *propname, u8 *val)
{
return device_property_read_u8_array(dev, propname, val, 1);
}
static inline int device_property_read_u16(struct device *dev,
const char *propname, u16 *val)
{
return device_property_read_u16_array(dev, propname, val, 1);
}
static inline int device_property_read_u32(struct device *dev,
const char *propname, u32 *val)
{
return device_property_read_u32_array(dev, propname, val, 1);
}
static inline int device_property_read_u64(struct device *dev,
const char *propname, u64 *val)
{
return device_property_read_u64_array(dev, propname, val, 1);
}
static inline int device_property_count_u8(struct device *dev, const char *propname)
{
return device_property_read_u8_array(dev, propname, NULL, 0);
}
static inline int device_property_count_u16(struct device *dev, const char *propname)
{
return device_property_read_u16_array(dev, propname, NULL, 0);
}
static inline int device_property_count_u32(struct device *dev, const char *propname)
{
return device_property_read_u32_array(dev, propname, NULL, 0);
}
static inline int device_property_count_u64(struct device *dev, const char *propname)
{
return device_property_read_u64_array(dev, propname, NULL, 0);
}
static inline int device_property_string_array_count(struct device *dev,
const char *propname)
{
return device_property_read_string_array(dev, propname, NULL, 0);
}
static inline bool fwnode_property_read_bool(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_present(fwnode, propname);
}
static inline int fwnode_property_read_u8(const struct fwnode_handle *fwnode,
const char *propname, u8 *val)
{
return fwnode_property_read_u8_array(fwnode, propname, val, 1);
}
static inline int fwnode_property_read_u16(const struct fwnode_handle *fwnode,
const char *propname, u16 *val)
{
return fwnode_property_read_u16_array(fwnode, propname, val, 1);
}
static inline int fwnode_property_read_u32(const struct fwnode_handle *fwnode,
const char *propname, u32 *val)
{
return fwnode_property_read_u32_array(fwnode, propname, val, 1);
}
static inline int fwnode_property_read_u64(const struct fwnode_handle *fwnode,
const char *propname, u64 *val)
{
return fwnode_property_read_u64_array(fwnode, propname, val, 1);
}
static inline int fwnode_property_count_u8(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_read_u8_array(fwnode, propname, NULL, 0);
}
static inline int fwnode_property_count_u16(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_read_u16_array(fwnode, propname, NULL, 0);
}
static inline int fwnode_property_count_u32(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_read_u32_array(fwnode, propname, NULL, 0);
}
static inline int fwnode_property_count_u64(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_read_u64_array(fwnode, propname, NULL, 0);
}
static inline int
fwnode_property_string_array_count(const struct fwnode_handle *fwnode,
const char *propname)
{
return fwnode_property_read_string_array(fwnode, propname, NULL, 0);
}
struct software_node;
/**
* struct software_node_ref_args - Reference property with additional arguments
* @node: Reference to a software node
* @nargs: Number of elements in @args array
* @args: Integer arguments
*/
struct software_node_ref_args {
const struct software_node *node;
unsigned int nargs;
u64 args[NR_FWNODE_REFERENCE_ARGS];
};
#define SOFTWARE_NODE_REFERENCE(_ref_, ...) \
(const struct software_node_ref_args) { \
.node = _ref_, \
.nargs = ARRAY_SIZE(((u64[]){ 0, ##__VA_ARGS__ })) - 1, \
.args = { __VA_ARGS__ }, \
}
/**
* struct property_entry - "Built-in" device property representation.
* @name: Name of the property.
* @length: Length of data making up the value.
* @is_inline: True when the property value is stored inline.
device property: Get rid of union aliasing Commit 318a19718261 (device property: refactor built-in properties support) went way too far and brought a union aliasing. Partially revert it here to get rid of union aliasing. Note, all Apple properties are considered as u8 arrays. To get a value of any of them the caller must use device_property_read_u8_array(). What's union aliasing? ~~~~~~~~~~~~~~~~~~~~~~ The C99 standard in section 6.2.5 paragraph 20 defines union type as "an overlapping nonempty set of member objects". It also states in section 6.7.2.1 paragraph 14 that "the value of at most one of the members can be stored in a union object at any time'. Union aliasing is a type punning mechanism using union members to store as one type and read back as another. Why it's not good? ~~~~~~~~~~~~~~~~~~ Section 6.2.6.1 paragraph 6 says that a union object may not be a trap representation, although its member objects may be. Meanwhile annex J.1 says that "the value of a union member other than the last one stored into" is unspecified [removed in C11]. In TC3, a footnote is added which specifies that accessing a member of a union other than the last one stored causes "the object representation" to be re-interpreted in the new type and specifically refers to this as "type punning". This conflicts to some degree with Annex J.1. While it's working in Linux with GCC, the use of union members to do type punning is not clear area in the C standard and might lead to unspecified behaviour. More information is available in this [1] blog post. [1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-15 17:32:02 +00:00
* @type: Type of the data in unions.
* @pointer: Pointer to the property when it is not stored inline.
* @value: Value of the property when it is stored inline.
*/
struct property_entry {
const char *name;
size_t length;
bool is_inline;
device property: Get rid of union aliasing Commit 318a19718261 (device property: refactor built-in properties support) went way too far and brought a union aliasing. Partially revert it here to get rid of union aliasing. Note, all Apple properties are considered as u8 arrays. To get a value of any of them the caller must use device_property_read_u8_array(). What's union aliasing? ~~~~~~~~~~~~~~~~~~~~~~ The C99 standard in section 6.2.5 paragraph 20 defines union type as "an overlapping nonempty set of member objects". It also states in section 6.7.2.1 paragraph 14 that "the value of at most one of the members can be stored in a union object at any time'. Union aliasing is a type punning mechanism using union members to store as one type and read back as another. Why it's not good? ~~~~~~~~~~~~~~~~~~ Section 6.2.6.1 paragraph 6 says that a union object may not be a trap representation, although its member objects may be. Meanwhile annex J.1 says that "the value of a union member other than the last one stored into" is unspecified [removed in C11]. In TC3, a footnote is added which specifies that accessing a member of a union other than the last one stored causes "the object representation" to be re-interpreted in the new type and specifically refers to this as "type punning". This conflicts to some degree with Annex J.1. While it's working in Linux with GCC, the use of union members to do type punning is not clear area in the C standard and might lead to unspecified behaviour. More information is available in this [1] blog post. [1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-15 17:32:02 +00:00
enum dev_prop_type type;
union {
const void *pointer;
union {
u8 u8_data[sizeof(u64) / sizeof(u8)];
u16 u16_data[sizeof(u64) / sizeof(u16)];
u32 u32_data[sizeof(u64) / sizeof(u32)];
u64 u64_data[sizeof(u64) / sizeof(u64)];
const char *str[sizeof(u64) / sizeof(char *)];
} value;
};
};
/*
* Note: the below initializers for the anonymous union are carefully
* crafted to avoid gcc-4.4.4's problems with initialization of anon unions
* and structs.
*/
#define __PROPERTY_ENTRY_ELEMENT_SIZE(_elem_) \
sizeof(((struct property_entry *)NULL)->value._elem_[0])
#define __PROPERTY_ENTRY_ARRAY_ELSIZE_LEN(_name_, _elsize_, _Type_, \
_val_, _len_) \
device property: Get rid of union aliasing Commit 318a19718261 (device property: refactor built-in properties support) went way too far and brought a union aliasing. Partially revert it here to get rid of union aliasing. Note, all Apple properties are considered as u8 arrays. To get a value of any of them the caller must use device_property_read_u8_array(). What's union aliasing? ~~~~~~~~~~~~~~~~~~~~~~ The C99 standard in section 6.2.5 paragraph 20 defines union type as "an overlapping nonempty set of member objects". It also states in section 6.7.2.1 paragraph 14 that "the value of at most one of the members can be stored in a union object at any time'. Union aliasing is a type punning mechanism using union members to store as one type and read back as another. Why it's not good? ~~~~~~~~~~~~~~~~~~ Section 6.2.6.1 paragraph 6 says that a union object may not be a trap representation, although its member objects may be. Meanwhile annex J.1 says that "the value of a union member other than the last one stored into" is unspecified [removed in C11]. In TC3, a footnote is added which specifies that accessing a member of a union other than the last one stored causes "the object representation" to be re-interpreted in the new type and specifically refers to this as "type punning". This conflicts to some degree with Annex J.1. While it's working in Linux with GCC, the use of union members to do type punning is not clear area in the C standard and might lead to unspecified behaviour. More information is available in this [1] blog post. [1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-15 17:32:02 +00:00
(struct property_entry) { \
.name = _name_, \
.length = (_len_) * (_elsize_), \
device property: Get rid of union aliasing Commit 318a19718261 (device property: refactor built-in properties support) went way too far and brought a union aliasing. Partially revert it here to get rid of union aliasing. Note, all Apple properties are considered as u8 arrays. To get a value of any of them the caller must use device_property_read_u8_array(). What's union aliasing? ~~~~~~~~~~~~~~~~~~~~~~ The C99 standard in section 6.2.5 paragraph 20 defines union type as "an overlapping nonempty set of member objects". It also states in section 6.7.2.1 paragraph 14 that "the value of at most one of the members can be stored in a union object at any time'. Union aliasing is a type punning mechanism using union members to store as one type and read back as another. Why it's not good? ~~~~~~~~~~~~~~~~~~ Section 6.2.6.1 paragraph 6 says that a union object may not be a trap representation, although its member objects may be. Meanwhile annex J.1 says that "the value of a union member other than the last one stored into" is unspecified [removed in C11]. In TC3, a footnote is added which specifies that accessing a member of a union other than the last one stored causes "the object representation" to be re-interpreted in the new type and specifically refers to this as "type punning". This conflicts to some degree with Annex J.1. While it's working in Linux with GCC, the use of union members to do type punning is not clear area in the C standard and might lead to unspecified behaviour. More information is available in this [1] blog post. [1]: https://davmac.wordpress.com/2010/02/26/c99-revisited/ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-15 17:32:02 +00:00
.type = DEV_PROP_##_Type_, \
{ .pointer = _val_ }, \
}
#define __PROPERTY_ENTRY_ARRAY_LEN(_name_, _elem_, _Type_, _val_, _len_)\
__PROPERTY_ENTRY_ARRAY_ELSIZE_LEN(_name_, \
__PROPERTY_ENTRY_ELEMENT_SIZE(_elem_), \
_Type_, _val_, _len_)
#define PROPERTY_ENTRY_U8_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_LEN(_name_, u8_data, U8, _val_, _len_)
#define PROPERTY_ENTRY_U16_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_LEN(_name_, u16_data, U16, _val_, _len_)
#define PROPERTY_ENTRY_U32_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_LEN(_name_, u32_data, U32, _val_, _len_)
#define PROPERTY_ENTRY_U64_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_LEN(_name_, u64_data, U64, _val_, _len_)
#define PROPERTY_ENTRY_STRING_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_LEN(_name_, str, STRING, _val_, _len_)
#define PROPERTY_ENTRY_REF_ARRAY_LEN(_name_, _val_, _len_) \
__PROPERTY_ENTRY_ARRAY_ELSIZE_LEN(_name_, \
sizeof(struct software_node_ref_args), \
REF, _val_, _len_)
#define PROPERTY_ENTRY_U8_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_U8_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define PROPERTY_ENTRY_U16_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_U16_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define PROPERTY_ENTRY_U32_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_U32_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define PROPERTY_ENTRY_U64_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_U64_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define PROPERTY_ENTRY_STRING_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_STRING_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define PROPERTY_ENTRY_REF_ARRAY(_name_, _val_) \
PROPERTY_ENTRY_REF_ARRAY_LEN(_name_, _val_, ARRAY_SIZE(_val_))
#define __PROPERTY_ENTRY_ELEMENT(_name_, _elem_, _Type_, _val_) \
(struct property_entry) { \
.name = _name_, \
.length = __PROPERTY_ENTRY_ELEMENT_SIZE(_elem_), \
.is_inline = true, \
.type = DEV_PROP_##_Type_, \
{ .value = { ._elem_[0] = _val_ } }, \
}
#define PROPERTY_ENTRY_U8(_name_, _val_) \
__PROPERTY_ENTRY_ELEMENT(_name_, u8_data, U8, _val_)
#define PROPERTY_ENTRY_U16(_name_, _val_) \
__PROPERTY_ENTRY_ELEMENT(_name_, u16_data, U16, _val_)
#define PROPERTY_ENTRY_U32(_name_, _val_) \
__PROPERTY_ENTRY_ELEMENT(_name_, u32_data, U32, _val_)
#define PROPERTY_ENTRY_U64(_name_, _val_) \
__PROPERTY_ENTRY_ELEMENT(_name_, u64_data, U64, _val_)
#define PROPERTY_ENTRY_STRING(_name_, _val_) \
__PROPERTY_ENTRY_ELEMENT(_name_, str, STRING, _val_)
#define PROPERTY_ENTRY_BOOL(_name_) \
(struct property_entry) { \
.name = _name_, \
.is_inline = true, \
}
#define PROPERTY_ENTRY_REF(_name_, _ref_, ...) \
(struct property_entry) { \
.name = _name_, \
.length = sizeof(struct software_node_ref_args), \
.type = DEV_PROP_REF, \
{ .pointer = &SOFTWARE_NODE_REFERENCE(_ref_, ##__VA_ARGS__), }, \
}
struct property_entry *
property_entries_dup(const struct property_entry *properties);
void property_entries_free(const struct property_entry *properties);
bool device_dma_supported(struct device *dev);
enum dev_dma_attr device_get_dma_attr(struct device *dev);
const void *device_get_match_data(struct device *dev);
int device_get_phy_mode(struct device *dev);
int fwnode_get_phy_mode(struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_graph_get_next_endpoint(
const struct fwnode_handle *fwnode, struct fwnode_handle *prev);
struct fwnode_handle *
fwnode_graph_get_port_parent(const struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_graph_get_remote_port_parent(
const struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_graph_get_remote_port(
const struct fwnode_handle *fwnode);
struct fwnode_handle *fwnode_graph_get_remote_endpoint(
const struct fwnode_handle *fwnode);
static inline bool fwnode_graph_is_endpoint(struct fwnode_handle *fwnode)
{
return fwnode_property_present(fwnode, "remote-endpoint");
}
/*
* Fwnode lookup flags
*
* @FWNODE_GRAPH_ENDPOINT_NEXT: In the case of no exact match, look for the
* closest endpoint ID greater than the specified
* one.
* @FWNODE_GRAPH_DEVICE_DISABLED: That the device to which the remote
* endpoint of the given endpoint belongs to,
* may be disabled, or that the endpoint is not
* connected.
*/
#define FWNODE_GRAPH_ENDPOINT_NEXT BIT(0)
#define FWNODE_GRAPH_DEVICE_DISABLED BIT(1)
struct fwnode_handle *
fwnode_graph_get_endpoint_by_id(const struct fwnode_handle *fwnode,
u32 port, u32 endpoint, unsigned long flags);
unsigned int fwnode_graph_get_endpoint_count(struct fwnode_handle *fwnode,
unsigned long flags);
#define fwnode_graph_for_each_endpoint(fwnode, child) \
for (child = NULL; \
(child = fwnode_graph_get_next_endpoint(fwnode, child)); )
int fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
struct fwnode_endpoint *endpoint);
typedef void *(*devcon_match_fn_t)(struct fwnode_handle *fwnode, const char *id,
void *data);
void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
const char *con_id, void *data,
devcon_match_fn_t match);
static inline void *device_connection_find_match(struct device *dev,
const char *con_id, void *data,
devcon_match_fn_t match)
{
return fwnode_connection_find_match(dev_fwnode(dev), con_id, data, match);
}
drivers: base: Introducing software nodes to the firmware node framework Software node is a new struct fwnode_handle type that can be used to describe devices in kernel (software). It is meant to complement fwnodes representing real firmware nodes when they are incomplete (for example missing device properties) and to supply the primary fwnode when the firmware lacks hardware description for a device completely. The software node type is really meant to replace the currently used "property_set" struct fwnode_handle type. The handling of struct property_set is glued to the generic device property handling code, and it is not possible to create a struct property_set independently from the device that it is bind to. struct property_set is only created when device properties are added to already initialized struct device, and control of it is only possible from the generic property handling code. Software nodes are instead designed to be created independently from the device entries (struct device). It makes them much more flexible, as then the device meant to be bind to the node can be created at a later time, and from another location. It is also possible to bind multiple devices to a single software node if needed. The software node implementation also includes support for node hierarchy, which was the main motivation for this commit. The node hierarchy was something that was requested for the struct property_set, but it did not seem reasonable to try to extend the property_set support for that purpose. struct property_set was really meant only for device property handling like the name suggests. Support for struct property_set is not yet removed in this commit, but it will be in the following one. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-09 14:21:36 +00:00
/* -------------------------------------------------------------------------- */
/* Software fwnode support - when HW description is incomplete or missing */
/**
* struct software_node - Software node description
* @name: Name of the software node
* @parent: Parent of the software node
* @properties: Array of device properties
*/
struct software_node {
const char *name;
const struct software_node *parent;
const struct property_entry *properties;
};
drivers: base: Introducing software nodes to the firmware node framework Software node is a new struct fwnode_handle type that can be used to describe devices in kernel (software). It is meant to complement fwnodes representing real firmware nodes when they are incomplete (for example missing device properties) and to supply the primary fwnode when the firmware lacks hardware description for a device completely. The software node type is really meant to replace the currently used "property_set" struct fwnode_handle type. The handling of struct property_set is glued to the generic device property handling code, and it is not possible to create a struct property_set independently from the device that it is bind to. struct property_set is only created when device properties are added to already initialized struct device, and control of it is only possible from the generic property handling code. Software nodes are instead designed to be created independently from the device entries (struct device). It makes them much more flexible, as then the device meant to be bind to the node can be created at a later time, and from another location. It is also possible to bind multiple devices to a single software node if needed. The software node implementation also includes support for node hierarchy, which was the main motivation for this commit. The node hierarchy was something that was requested for the struct property_set, but it did not seem reasonable to try to extend the property_set support for that purpose. struct property_set was really meant only for device property handling like the name suggests. Support for struct property_set is not yet removed in this commit, but it will be in the following one. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-09 14:21:36 +00:00
bool is_software_node(const struct fwnode_handle *fwnode);
const struct software_node *
to_software_node(const struct fwnode_handle *fwnode);
struct fwnode_handle *software_node_fwnode(const struct software_node *node);
const struct software_node *
software_node_find_by_name(const struct software_node *parent,
const char *name);
int software_node_register_nodes(const struct software_node *nodes);
void software_node_unregister_nodes(const struct software_node *nodes);
int software_node_register_node_group(const struct software_node **node_group);
void software_node_unregister_node_group(const struct software_node **node_group);
int software_node_register(const struct software_node *node);
software node: implement software_node_unregister() Sometimes it is better to unregister individual nodes instead of trying to do them all at once with software_node_unregister_nodes(), so create software_node_unregister() so that you can unregister them one at a time. This is especially important when creating nodes in a hierarchy, with parent -> children representations. Children always need to be removed before a parent is, as the swnode logic assumes this is going to be the case. Fix up the lib/test_printf.c fwnode_pointer() test which to use this new function as it had the problem of tearing things down in the backwards order. Fixes: f1ce39df508d ("lib/test_printf: Add tests for %pfw printk modifier") Cc: stable <stable@vger.kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Reported-by: kernel test robot <rong.a.chen@intel.com> Reported-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Petr Mladek <pmladek@suse.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20200524153041.2361-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-24 15:30:40 +00:00
void software_node_unregister(const struct software_node *node);
drivers: base: Introducing software nodes to the firmware node framework Software node is a new struct fwnode_handle type that can be used to describe devices in kernel (software). It is meant to complement fwnodes representing real firmware nodes when they are incomplete (for example missing device properties) and to supply the primary fwnode when the firmware lacks hardware description for a device completely. The software node type is really meant to replace the currently used "property_set" struct fwnode_handle type. The handling of struct property_set is glued to the generic device property handling code, and it is not possible to create a struct property_set independently from the device that it is bind to. struct property_set is only created when device properties are added to already initialized struct device, and control of it is only possible from the generic property handling code. Software nodes are instead designed to be created independently from the device entries (struct device). It makes them much more flexible, as then the device meant to be bind to the node can be created at a later time, and from another location. It is also possible to bind multiple devices to a single software node if needed. The software node implementation also includes support for node hierarchy, which was the main motivation for this commit. The node hierarchy was something that was requested for the struct property_set, but it did not seem reasonable to try to extend the property_set support for that purpose. struct property_set was really meant only for device property handling like the name suggests. Support for struct property_set is not yet removed in this commit, but it will be in the following one. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-09 14:21:36 +00:00
struct fwnode_handle *
fwnode_create_software_node(const struct property_entry *properties,
const struct fwnode_handle *parent);
void fwnode_remove_software_node(struct fwnode_handle *fwnode);
int device_add_software_node(struct device *dev, const struct software_node *node);
void device_remove_software_node(struct device *dev);
software node: Provide replacement for device_add_properties() At the moment the function device_del() is calling device_remove_properties() unconditionally. That will result into the reference count of the software node attached to the device being decremented, and in most cases it will hit 0 at that point. So in practice device_del() will unregister the software node attached to the device, even if that was not the intention of the caller. Right now software nodes can not be reused or shared because of that. So device_del() can not unregister the software nodes unconditionally like that. Unfortunately some of the users of device_add_properties() are now relying on this behaviour. Because of that, and also in general, we do need a function that can offer similar behaviour where the lifetime of the software node is bound to the lifetime of the device. But it just has to be a separate function so the behaviour is optional. We can not remove the device_remove_properties() call from device_del() before we have that new function, and before we have replaced device_add_properties() calls with it in all the places that require that behaviour. This adds function device_create_managed_software_node() that can be used for exactly that purpose. Software nodes created with it are declared "managed", and separate handling for those nodes is added to the software node code. The reference count of the "managed" nodes is decremented when the device they are attached to is removed. This will not affect the other nodes that are not declared "managed". The function device_create_managed_software_node() has also one additional feature that device_add_properties() does not have. It allows the software nodes created with it to be part of a node hierarchy by taking also an optional parent node as parameter. Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Link: https://lore.kernel.org/r/20210204141711.53775-2-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-04 14:17:06 +00:00
int device_create_managed_software_node(struct device *dev,
const struct property_entry *properties,
const struct software_node *parent);
#endif /* _LINUX_PROPERTY_H_ */