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path: root/drivers/of/base.c
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-rw-r--r--drivers/of/base.c318
1 files changed, 312 insertions, 6 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c
index e6627b2320f1..cb96888d1427 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -20,8 +20,10 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/spinlock.h>
+#include <linux/proc_fs.h>
struct device_node *allnodes;
+struct device_node *of_chosen;
/* use when traversing tree through the allnext, child, sibling,
* or parent members of struct device_node.
@@ -37,7 +39,7 @@ int of_n_addr_cells(struct device_node *np)
np = np->parent;
ip = of_get_property(np, "#address-cells", NULL);
if (ip)
- return *ip;
+ return be32_to_cpup(ip);
} while (np->parent);
/* No #address-cells property for the root node */
return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
@@ -53,13 +55,88 @@ int of_n_size_cells(struct device_node *np)
np = np->parent;
ip = of_get_property(np, "#size-cells", NULL);
if (ip)
- return *ip;
+ return be32_to_cpup(ip);
} while (np->parent);
/* No #size-cells property for the root node */
return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
}
EXPORT_SYMBOL(of_n_size_cells);
+#if !defined(CONFIG_SPARC) /* SPARC doesn't do ref counting (yet) */
+/**
+ * of_node_get - Increment refcount of a node
+ * @node: Node to inc refcount, NULL is supported to
+ * simplify writing of callers
+ *
+ * Returns node.
+ */
+struct device_node *of_node_get(struct device_node *node)
+{
+ if (node)
+ kref_get(&node->kref);
+ return node;
+}
+EXPORT_SYMBOL(of_node_get);
+
+static inline struct device_node *kref_to_device_node(struct kref *kref)
+{
+ return container_of(kref, struct device_node, kref);
+}
+
+/**
+ * of_node_release - release a dynamically allocated node
+ * @kref: kref element of the node to be released
+ *
+ * In of_node_put() this function is passed to kref_put()
+ * as the destructor.
+ */
+static void of_node_release(struct kref *kref)
+{
+ struct device_node *node = kref_to_device_node(kref);
+ struct property *prop = node->properties;
+
+ /* We should never be releasing nodes that haven't been detached. */
+ if (!of_node_check_flag(node, OF_DETACHED)) {
+ pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
+ dump_stack();
+ kref_init(&node->kref);
+ return;
+ }
+
+ if (!of_node_check_flag(node, OF_DYNAMIC))
+ return;
+
+ while (prop) {
+ struct property *next = prop->next;
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+ prop = next;
+
+ if (!prop) {
+ prop = node->deadprops;
+ node->deadprops = NULL;
+ }
+ }
+ kfree(node->full_name);
+ kfree(node->data);
+ kfree(node);
+}
+
+/**
+ * of_node_put - Decrement refcount of a node
+ * @node: Node to dec refcount, NULL is supported to
+ * simplify writing of callers
+ *
+ */
+void of_node_put(struct device_node *node)
+{
+ if (node)
+ kref_put(&node->kref, of_node_release);
+}
+EXPORT_SYMBOL(of_node_put);
+#endif /* !CONFIG_SPARC */
+
struct property *of_find_property(const struct device_node *np,
const char *name,
int *lenp)
@@ -144,6 +221,27 @@ int of_device_is_compatible(const struct device_node *device,
EXPORT_SYMBOL(of_device_is_compatible);
/**
+ * of_machine_is_compatible - Test root of device tree for a given compatible value
+ * @compat: compatible string to look for in root node's compatible property.
+ *
+ * Returns true if the root node has the given value in its
+ * compatible property.
+ */
+int of_machine_is_compatible(const char *compat)
+{
+ struct device_node *root;
+ int rc = 0;
+
+ root = of_find_node_by_path("/");
+ if (root) {
+ rc = of_device_is_compatible(root, compat);
+ of_node_put(root);
+ }
+ return rc;
+}
+EXPORT_SYMBOL(of_machine_is_compatible);
+
+/**
* of_device_is_available - check if a device is available for use
*
* @device: Node to check for availability
@@ -519,6 +617,27 @@ int of_modalias_node(struct device_node *node, char *modalias, int len)
EXPORT_SYMBOL_GPL(of_modalias_node);
/**
+ * of_find_node_by_phandle - Find a node given a phandle
+ * @handle: phandle of the node to find
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_find_node_by_phandle(phandle handle)
+{
+ struct device_node *np;
+
+ read_lock(&devtree_lock);
+ for (np = allnodes; np; np = np->allnext)
+ if (np->phandle == handle)
+ break;
+ of_node_get(np);
+ read_unlock(&devtree_lock);
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_phandle);
+
+/**
* of_parse_phandle - Resolve a phandle property to a device_node pointer
* @np: Pointer to device node holding phandle property
* @phandle_name: Name of property holding a phandle value
@@ -578,8 +697,8 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
const void **out_args)
{
int ret = -EINVAL;
- const u32 *list;
- const u32 *list_end;
+ const __be32 *list;
+ const __be32 *list_end;
int size;
int cur_index = 0;
struct device_node *node = NULL;
@@ -593,7 +712,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
list_end = list + size / sizeof(*list);
while (list < list_end) {
- const u32 *cells;
+ const __be32 *cells;
const phandle *phandle;
phandle = list++;
@@ -617,7 +736,7 @@ int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
goto err1;
}
- list += *cells;
+ list += be32_to_cpup(cells);
if (list > list_end) {
pr_debug("%s: insufficient arguments length\n",
np->full_name);
@@ -658,3 +777,190 @@ err0:
return ret;
}
EXPORT_SYMBOL(of_parse_phandles_with_args);
+
+/**
+ * prom_add_property - Add a property to a node
+ */
+int prom_add_property(struct device_node *np, struct property *prop)
+{
+ struct property **next;
+ unsigned long flags;
+
+ prop->next = NULL;
+ write_lock_irqsave(&devtree_lock, flags);
+ next = &np->properties;
+ while (*next) {
+ if (strcmp(prop->name, (*next)->name) == 0) {
+ /* duplicate ! don't insert it */
+ write_unlock_irqrestore(&devtree_lock, flags);
+ return -1;
+ }
+ next = &(*next)->next;
+ }
+ *next = prop;
+ write_unlock_irqrestore(&devtree_lock, flags);
+
+#ifdef CONFIG_PROC_DEVICETREE
+ /* try to add to proc as well if it was initialized */
+ if (np->pde)
+ proc_device_tree_add_prop(np->pde, prop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+ return 0;
+}
+
+/**
+ * prom_remove_property - Remove a property from a node.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties"
+ * list, so it won't be found any more.
+ */
+int prom_remove_property(struct device_node *np, struct property *prop)
+{
+ struct property **next;
+ unsigned long flags;
+ int found = 0;
+
+ write_lock_irqsave(&devtree_lock, flags);
+ next = &np->properties;
+ while (*next) {
+ if (*next == prop) {
+ /* found the node */
+ *next = prop->next;
+ prop->next = np->deadprops;
+ np->deadprops = prop;
+ found = 1;
+ break;
+ }
+ next = &(*next)->next;
+ }
+ write_unlock_irqrestore(&devtree_lock, flags);
+
+ if (!found)
+ return -ENODEV;
+
+#ifdef CONFIG_PROC_DEVICETREE
+ /* try to remove the proc node as well */
+ if (np->pde)
+ proc_device_tree_remove_prop(np->pde, prop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+ return 0;
+}
+
+/*
+ * prom_update_property - Update a property in a node.
+ *
+ * Note that we don't actually remove it, since we have given out
+ * who-knows-how-many pointers to the data using get-property.
+ * Instead we just move the property to the "dead properties" list,
+ * and add the new property to the property list
+ */
+int prom_update_property(struct device_node *np,
+ struct property *newprop,
+ struct property *oldprop)
+{
+ struct property **next;
+ unsigned long flags;
+ int found = 0;
+
+ write_lock_irqsave(&devtree_lock, flags);
+ next = &np->properties;
+ while (*next) {
+ if (*next == oldprop) {
+ /* found the node */
+ newprop->next = oldprop->next;
+ *next = newprop;
+ oldprop->next = np->deadprops;
+ np->deadprops = oldprop;
+ found = 1;
+ break;
+ }
+ next = &(*next)->next;
+ }
+ write_unlock_irqrestore(&devtree_lock, flags);
+
+ if (!found)
+ return -ENODEV;
+
+#ifdef CONFIG_PROC_DEVICETREE
+ /* try to add to proc as well if it was initialized */
+ if (np->pde)
+ proc_device_tree_update_prop(np->pde, newprop, oldprop);
+#endif /* CONFIG_PROC_DEVICETREE */
+
+ return 0;
+}
+
+#if defined(CONFIG_OF_DYNAMIC)
+/*
+ * Support for dynamic device trees.
+ *
+ * On some platforms, the device tree can be manipulated at runtime.
+ * The routines in this section support adding, removing and changing
+ * device tree nodes.
+ */
+
+/**
+ * of_attach_node - Plug a device node into the tree and global list.
+ */
+void of_attach_node(struct device_node *np)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&devtree_lock, flags);
+ np->sibling = np->parent->child;
+ np->allnext = allnodes;
+ np->parent->child = np;
+ allnodes = np;
+ write_unlock_irqrestore(&devtree_lock, flags);
+}
+
+/**
+ * of_detach_node - "Unplug" a node from the device tree.
+ *
+ * The caller must hold a reference to the node. The memory associated with
+ * the node is not freed until its refcount goes to zero.
+ */
+void of_detach_node(struct device_node *np)
+{
+ struct device_node *parent;
+ unsigned long flags;
+
+ write_lock_irqsave(&devtree_lock, flags);
+
+ parent = np->parent;
+ if (!parent)
+ goto out_unlock;
+
+ if (allnodes == np)
+ allnodes = np->allnext;
+ else {
+ struct device_node *prev;
+ for (prev = allnodes;
+ prev->allnext != np;
+ prev = prev->allnext)
+ ;
+ prev->allnext = np->allnext;
+ }
+
+ if (parent->child == np)
+ parent->child = np->sibling;
+ else {
+ struct device_node *prevsib;
+ for (prevsib = np->parent->child;
+ prevsib->sibling != np;
+ prevsib = prevsib->sibling)
+ ;
+ prevsib->sibling = np->sibling;
+ }
+
+ of_node_set_flag(np, OF_DETACHED);
+
+out_unlock:
+ write_unlock_irqrestore(&devtree_lock, flags);
+}
+#endif /* defined(CONFIG_OF_DYNAMIC) */
+