WSL2-Linux-Kernel/drivers/base/swnode.c

677 строки
15 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Software nodes for the firmware node framework.
*
* Copyright (C) 2018, Intel Corporation
* Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/property.h>
#include <linux/slab.h>
struct software_node {
int id;
struct kobject kobj;
struct fwnode_handle fwnode;
/* hierarchy */
struct ida child_ids;
struct list_head entry;
struct list_head children;
struct software_node *parent;
/* properties */
const struct property_entry *properties;
};
static DEFINE_IDA(swnode_root_ids);
static struct kset *swnode_kset;
#define kobj_to_swnode(_kobj_) container_of(_kobj_, struct software_node, kobj)
static const struct fwnode_operations software_node_ops;
bool is_software_node(const struct fwnode_handle *fwnode)
{
return !IS_ERR_OR_NULL(fwnode) && fwnode->ops == &software_node_ops;
}
#define to_software_node(__fwnode) \
({ \
typeof(__fwnode) __to_software_node_fwnode = __fwnode; \
\
is_software_node(__to_software_node_fwnode) ? \
container_of(__to_software_node_fwnode, \
struct software_node, fwnode) : \
NULL; \
})
/* -------------------------------------------------------------------------- */
/* property_entry processing */
static const struct property_entry *
property_entry_get(const struct property_entry *prop, const char *name)
{
if (!prop)
return NULL;
for (; prop->name; prop++)
if (!strcmp(name, prop->name))
return prop;
return NULL;
}
static void
property_set_pointer(struct property_entry *prop, const void *pointer)
{
switch (prop->type) {
case DEV_PROP_U8:
if (prop->is_array)
prop->pointer.u8_data = pointer;
else
prop->value.u8_data = *((u8 *)pointer);
break;
case DEV_PROP_U16:
if (prop->is_array)
prop->pointer.u16_data = pointer;
else
prop->value.u16_data = *((u16 *)pointer);
break;
case DEV_PROP_U32:
if (prop->is_array)
prop->pointer.u32_data = pointer;
else
prop->value.u32_data = *((u32 *)pointer);
break;
case DEV_PROP_U64:
if (prop->is_array)
prop->pointer.u64_data = pointer;
else
prop->value.u64_data = *((u64 *)pointer);
break;
case DEV_PROP_STRING:
if (prop->is_array)
prop->pointer.str = pointer;
else
prop->value.str = pointer;
break;
default:
break;
}
}
static const void *property_get_pointer(const struct property_entry *prop)
{
switch (prop->type) {
case DEV_PROP_U8:
if (prop->is_array)
return prop->pointer.u8_data;
return &prop->value.u8_data;
case DEV_PROP_U16:
if (prop->is_array)
return prop->pointer.u16_data;
return &prop->value.u16_data;
case DEV_PROP_U32:
if (prop->is_array)
return prop->pointer.u32_data;
return &prop->value.u32_data;
case DEV_PROP_U64:
if (prop->is_array)
return prop->pointer.u64_data;
return &prop->value.u64_data;
case DEV_PROP_STRING:
if (prop->is_array)
return prop->pointer.str;
return &prop->value.str;
default:
return NULL;
}
}
static const void *property_entry_find(const struct property_entry *props,
const char *propname, size_t length)
{
const struct property_entry *prop;
const void *pointer;
prop = property_entry_get(props, propname);
if (!prop)
return ERR_PTR(-EINVAL);
pointer = property_get_pointer(prop);
if (!pointer)
return ERR_PTR(-ENODATA);
if (length > prop->length)
return ERR_PTR(-EOVERFLOW);
return pointer;
}
static int property_entry_read_u8_array(const struct property_entry *props,
const char *propname,
u8 *values, size_t nval)
{
const void *pointer;
size_t length = nval * sizeof(*values);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(values, pointer, length);
return 0;
}
static int property_entry_read_u16_array(const struct property_entry *props,
const char *propname,
u16 *values, size_t nval)
{
const void *pointer;
size_t length = nval * sizeof(*values);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(values, pointer, length);
return 0;
}
static int property_entry_read_u32_array(const struct property_entry *props,
const char *propname,
u32 *values, size_t nval)
{
const void *pointer;
size_t length = nval * sizeof(*values);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(values, pointer, length);
return 0;
}
static int property_entry_read_u64_array(const struct property_entry *props,
const char *propname,
u64 *values, size_t nval)
{
const void *pointer;
size_t length = nval * sizeof(*values);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(values, pointer, length);
return 0;
}
static int
property_entry_count_elems_of_size(const struct property_entry *props,
const char *propname, size_t length)
{
const struct property_entry *prop;
prop = property_entry_get(props, propname);
if (!prop)
return -EINVAL;
return prop->length / length;
}
static int property_entry_read_int_array(const struct property_entry *props,
const char *name,
unsigned int elem_size, void *val,
size_t nval)
{
if (!val)
return property_entry_count_elems_of_size(props, name,
elem_size);
switch (elem_size) {
case sizeof(u8):
return property_entry_read_u8_array(props, name, val, nval);
case sizeof(u16):
return property_entry_read_u16_array(props, name, val, nval);
case sizeof(u32):
return property_entry_read_u32_array(props, name, val, nval);
case sizeof(u64):
return property_entry_read_u64_array(props, name, val, nval);
}
return -ENXIO;
}
static int property_entry_read_string_array(const struct property_entry *props,
const char *propname,
const char **strings, size_t nval)
{
const struct property_entry *prop;
const void *pointer;
size_t array_len, length;
/* Find out the array length. */
prop = property_entry_get(props, propname);
if (!prop)
return -EINVAL;
if (prop->is_array)
/* Find the length of an array. */
array_len = property_entry_count_elems_of_size(props, propname,
sizeof(const char *));
else
/* The array length for a non-array string property is 1. */
array_len = 1;
/* Return how many there are if strings is NULL. */
if (!strings)
return array_len;
array_len = min(nval, array_len);
length = array_len * sizeof(*strings);
pointer = property_entry_find(props, propname, length);
if (IS_ERR(pointer))
return PTR_ERR(pointer);
memcpy(strings, pointer, length);
return array_len;
}
static void property_entry_free_data(const struct property_entry *p)
{
const void *pointer = property_get_pointer(p);
size_t i, nval;
if (p->is_array) {
if (p->type == DEV_PROP_STRING && p->pointer.str) {
nval = p->length / sizeof(const char *);
for (i = 0; i < nval; i++)
kfree(p->pointer.str[i]);
}
kfree(pointer);
} else if (p->type == DEV_PROP_STRING) {
kfree(p->value.str);
}
kfree(p->name);
}
static int property_copy_string_array(struct property_entry *dst,
const struct property_entry *src)
{
const char **d;
size_t nval = src->length / sizeof(*d);
int i;
d = kcalloc(nval, sizeof(*d), GFP_KERNEL);
if (!d)
return -ENOMEM;
for (i = 0; i < nval; i++) {
d[i] = kstrdup(src->pointer.str[i], GFP_KERNEL);
if (!d[i] && src->pointer.str[i]) {
while (--i >= 0)
kfree(d[i]);
kfree(d);
return -ENOMEM;
}
}
dst->pointer.str = d;
return 0;
}
static int property_entry_copy_data(struct property_entry *dst,
const struct property_entry *src)
{
const void *pointer = property_get_pointer(src);
const void *new;
int error;
if (src->is_array) {
if (!src->length)
return -ENODATA;
if (src->type == DEV_PROP_STRING) {
error = property_copy_string_array(dst, src);
if (error)
return error;
new = dst->pointer.str;
} else {
new = kmemdup(pointer, src->length, GFP_KERNEL);
if (!new)
return -ENOMEM;
}
} else if (src->type == DEV_PROP_STRING) {
new = kstrdup(src->value.str, GFP_KERNEL);
if (!new && src->value.str)
return -ENOMEM;
} else {
new = pointer;
}
dst->length = src->length;
dst->is_array = src->is_array;
dst->type = src->type;
property_set_pointer(dst, new);
dst->name = kstrdup(src->name, GFP_KERNEL);
if (!dst->name)
goto out_free_data;
return 0;
out_free_data:
property_entry_free_data(dst);
return -ENOMEM;
}
/**
* property_entries_dup - duplicate array of properties
* @properties: array of properties to copy
*
* This function creates a deep copy of the given NULL-terminated array
* of property entries.
*/
struct property_entry *
property_entries_dup(const struct property_entry *properties)
{
struct property_entry *p;
int i, n = 0;
int ret;
while (properties[n].name)
n++;
p = kcalloc(n + 1, sizeof(*p), GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
for (i = 0; i < n; i++) {
ret = property_entry_copy_data(&p[i], &properties[i]);
if (ret) {
while (--i >= 0)
property_entry_free_data(&p[i]);
kfree(p);
return ERR_PTR(ret);
}
}
return p;
}
EXPORT_SYMBOL_GPL(property_entries_dup);
/**
* property_entries_free - free previously allocated array of properties
* @properties: array of properties to destroy
*
* This function frees given NULL-terminated array of property entries,
* along with their data.
*/
void property_entries_free(const struct property_entry *properties)
{
const struct property_entry *p;
if (!properties)
return;
for (p = properties; p->name; p++)
property_entry_free_data(p);
kfree(properties);
}
EXPORT_SYMBOL_GPL(property_entries_free);
/* -------------------------------------------------------------------------- */
/* fwnode operations */
static struct fwnode_handle *software_node_get(struct fwnode_handle *fwnode)
{
struct software_node *swnode = to_software_node(fwnode);
kobject_get(&swnode->kobj);
return &swnode->fwnode;
}
static void software_node_put(struct fwnode_handle *fwnode)
{
struct software_node *swnode = to_software_node(fwnode);
kobject_put(&swnode->kobj);
}
static bool software_node_property_present(const struct fwnode_handle *fwnode,
const char *propname)
{
return !!property_entry_get(to_software_node(fwnode)->properties,
propname);
}
static int software_node_read_int_array(const struct fwnode_handle *fwnode,
const char *propname,
unsigned int elem_size, void *val,
size_t nval)
{
struct software_node *swnode = to_software_node(fwnode);
return property_entry_read_int_array(swnode->properties, propname,
elem_size, val, nval);
}
static int software_node_read_string_array(const struct fwnode_handle *fwnode,
const char *propname,
const char **val, size_t nval)
{
struct software_node *swnode = to_software_node(fwnode);
return property_entry_read_string_array(swnode->properties, propname,
val, nval);
}
struct fwnode_handle *
software_node_get_parent(const struct fwnode_handle *fwnode)
{
struct software_node *swnode = to_software_node(fwnode);
return swnode ? (swnode->parent ? &swnode->parent->fwnode : NULL) :
NULL;
}
struct fwnode_handle *
software_node_get_next_child(const struct fwnode_handle *fwnode,
struct fwnode_handle *child)
{
struct software_node *p = to_software_node(fwnode);
struct software_node *c = to_software_node(child);
if (!p || list_empty(&p->children) ||
(c && list_is_last(&c->entry, &p->children)))
return NULL;
if (c)
c = list_next_entry(c, entry);
else
c = list_first_entry(&p->children, struct software_node, entry);
return &c->fwnode;
}
static const struct fwnode_operations software_node_ops = {
.get = software_node_get,
.put = software_node_put,
.property_present = software_node_property_present,
.property_read_int_array = software_node_read_int_array,
.property_read_string_array = software_node_read_string_array,
.get_parent = software_node_get_parent,
.get_next_child_node = software_node_get_next_child,
};
/* -------------------------------------------------------------------------- */
static int
software_node_register_properties(struct software_node *swnode,
const struct property_entry *properties)
{
struct property_entry *props;
props = property_entries_dup(properties);
if (IS_ERR(props))
return PTR_ERR(props);
swnode->properties = props;
return 0;
}
static void software_node_release(struct kobject *kobj)
{
struct software_node *swnode = kobj_to_swnode(kobj);
if (swnode->parent) {
ida_simple_remove(&swnode->parent->child_ids, swnode->id);
list_del(&swnode->entry);
} else {
ida_simple_remove(&swnode_root_ids, swnode->id);
}
ida_destroy(&swnode->child_ids);
property_entries_free(swnode->properties);
kfree(swnode);
}
static struct kobj_type software_node_type = {
.release = software_node_release,
.sysfs_ops = &kobj_sysfs_ops,
};
struct fwnode_handle *
fwnode_create_software_node(const struct property_entry *properties,
const struct fwnode_handle *parent)
{
struct software_node *p = NULL;
struct software_node *swnode;
int ret;
if (parent) {
if (IS_ERR(parent))
return ERR_CAST(parent);
if (!is_software_node(parent))
return ERR_PTR(-EINVAL);
p = to_software_node(parent);
}
swnode = kzalloc(sizeof(*swnode), GFP_KERNEL);
if (!swnode)
return ERR_PTR(-ENOMEM);
ret = ida_simple_get(p ? &p->child_ids : &swnode_root_ids, 0, 0,
GFP_KERNEL);
if (ret < 0) {
kfree(swnode);
return ERR_PTR(ret);
}
swnode->id = ret;
swnode->kobj.kset = swnode_kset;
swnode->fwnode.ops = &software_node_ops;
ida_init(&swnode->child_ids);
INIT_LIST_HEAD(&swnode->entry);
INIT_LIST_HEAD(&swnode->children);
swnode->parent = p;
if (p)
list_add_tail(&swnode->entry, &p->children);
ret = kobject_init_and_add(&swnode->kobj, &software_node_type,
p ? &p->kobj : NULL, "node%d", swnode->id);
if (ret) {
kobject_put(&swnode->kobj);
return ERR_PTR(ret);
}
ret = software_node_register_properties(swnode, properties);
if (ret) {
kobject_put(&swnode->kobj);
return ERR_PTR(ret);
}
kobject_uevent(&swnode->kobj, KOBJ_ADD);
return &swnode->fwnode;
}
EXPORT_SYMBOL_GPL(fwnode_create_software_node);
void fwnode_remove_software_node(struct fwnode_handle *fwnode)
{
struct software_node *swnode = to_software_node(fwnode);
if (!swnode)
return;
kobject_put(&swnode->kobj);
}
EXPORT_SYMBOL_GPL(fwnode_remove_software_node);
int software_node_notify(struct device *dev, unsigned long action)
{
struct fwnode_handle *fwnode = dev_fwnode(dev);
struct software_node *swnode;
int ret;
if (!fwnode)
return 0;
if (!is_software_node(fwnode))
fwnode = fwnode->secondary;
if (!is_software_node(fwnode))
return 0;
swnode = to_software_node(fwnode);
switch (action) {
case KOBJ_ADD:
ret = sysfs_create_link(&dev->kobj, &swnode->kobj,
"software_node");
if (ret)
break;
ret = sysfs_create_link(&swnode->kobj, &dev->kobj,
dev_name(dev));
if (ret) {
sysfs_remove_link(&dev->kobj, "software_node");
break;
}
kobject_get(&swnode->kobj);
break;
case KOBJ_REMOVE:
sysfs_remove_link(&swnode->kobj, dev_name(dev));
sysfs_remove_link(&dev->kobj, "software_node");
kobject_put(&swnode->kobj);
break;
default:
break;
}
return 0;
}
static int __init software_node_init(void)
{
swnode_kset = kset_create_and_add("software_nodes", NULL, kernel_kobj);
if (!swnode_kset)
return -ENOMEM;
return 0;
}
postcore_initcall(software_node_init);
static void __exit software_node_exit(void)
{
ida_destroy(&swnode_root_ids);
kset_unregister(swnode_kset);
}
__exitcall(software_node_exit);