static int of_overlay_apply_single_property(struct of_overlay *ov,
struct device_node *target, struct property *prop)
{
struct property *propn, *tprop;
/* NOTE: Multiple changes of single properties not supported */
tprop = of_find_property(target, prop->name, NULL);
/* special properties are not meant to be updated (silent NOP) */
if (of_prop_cmp(prop->name, "name") == 0 ||
of_prop_cmp(prop->name, "phandle") == 0 ||
of_prop_cmp(prop->name, "linux,phandle") == 0)
return 0;
propn = __of_prop_dup(prop, GFP_KERNEL);
if (propn == NULL)
return -ENOMEM;
/* not found? add */
if (tprop == NULL)
return of_changeset_add_property(&ov->cset, target, propn);
/* found? update */
return of_changeset_update_property(&ov->cset, target, propn);
}
/**
* add_changeset_property() - add @overlay_prop to overlay changeset
* @ovcs: overlay changeset
* @target_node: where to place @overlay_prop in live tree
* @overlay_prop: property to add or update, from overlay tree
* @is_symbols_prop: 1 if @overlay_prop is from node "/__symbols__"
*
* If @overlay_prop does not already exist in @target_node, add changeset entry
* to add @overlay_prop in @target_node, else add changeset entry to update
* value of @overlay_prop.
*
* Some special properties are not updated (no error returned).
*
* Update of property in symbols node is not allowed.
*
* Returns 0 on success, -ENOMEM if memory allocation failure, or -EINVAL if
* invalid @overlay.
*/
static int add_changeset_property(struct overlay_changeset *ovcs,
struct device_node *target_node,
struct property *overlay_prop,
bool is_symbols_prop)
{
struct property *new_prop = NULL, *prop;
int ret = 0;
prop = of_find_property(target_node, overlay_prop->name, NULL);
if (!of_prop_cmp(overlay_prop->name, "name") ||
!of_prop_cmp(overlay_prop->name, "phandle") ||
!of_prop_cmp(overlay_prop->name, "linux,phandle"))
return 0;
if (is_symbols_prop) {
if (prop)
return -EINVAL;
new_prop = dup_and_fixup_symbol_prop(ovcs, overlay_prop);
} else {
new_prop = __of_prop_dup(overlay_prop, GFP_KERNEL);
}
if (!new_prop)
return -ENOMEM;
if (!prop)
ret = of_changeset_add_property(&ovcs->cset, target_node,
new_prop);
else
ret = of_changeset_update_property(&ovcs->cset, target_node,
new_prop);
if (ret) {
kfree(new_prop->name);
kfree(new_prop->value);
kfree(new_prop);
}
return ret;
}
static struct property *__of_find_property(const struct device_node *np,
const char *name, int *lenp)
{
struct property *pp;
if (!np)
return NULL;
for (pp = np->properties; pp; pp = pp->next) {
if (of_prop_cmp(pp->name, name) == 0) {
if (lenp)
*lenp = pp->length;
break;
}
}
return pp;
}
struct property *of_find_property(const struct device_node *np,
const char *name,
int *lenp)
{
struct property *pp;
read_lock(&devtree_lock);
for (pp = np->properties; pp != 0; pp = pp->next) {
if (of_prop_cmp(pp->name, name) == 0) {
if (lenp != 0)
*lenp = pp->length;
break;
}
}
read_unlock(&devtree_lock);
return pp;
}
/**
* of_find_node_with_property - Find a node which has a property with
* the given name.
* @from: The node to start searching from or NULL, the node
* you pass will not be searched, only the next one
* will; typically, you pass what the previous call
* returned. of_node_put() will be called on it
* @prop_name: The name of the property to look for.
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
struct device_node *of_find_node_with_property(struct device_node *from,
const char *prop_name)
{
struct device_node *np;
struct property *pp;
read_lock(&devtree_lock);
np = from ? from->allnext : allnodes;
for (; np; np = np->allnext) {
for (pp = np->properties; pp != 0; pp = pp->next) {
if (of_prop_cmp(pp->name, prop_name) == 0) {
of_node_get(np);
goto out;
}
}
}
out:
of_node_put(from);
read_unlock(&devtree_lock);
return np;
}
/**
* of_find_node_with_property - Find a node which has a property with
* the given name.
* @from: The node to start searching from or NULL, the node
* you pass will not be searched, only the next one
* will; typically, you pass what the previous call
* returned. of_node_put() will be called on it
* @prop_name: The name of the property to look for.
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
struct device_node *of_find_node_with_property(struct device_node *from,
const char *prop_name)
{
struct device_node *np;
struct property *pp;
unsigned long flags;
raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext) {
for (pp = np->properties; pp; pp = pp->next) {
if (of_prop_cmp(pp->name, prop_name) == 0) {
of_node_get(np);
goto out;
}
}
}
out:
of_node_put(from);
raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}