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path: root/drivers/of/base.c
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Diffstat (limited to 'drivers/of/base.c')
-rw-r--r--drivers/of/base.c303
1 files changed, 207 insertions, 96 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 2390ddb22d60..321d3ef05006 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -24,38 +24,21 @@
#include <linux/slab.h>
#include <linux/proc_fs.h>
-/**
- * struct alias_prop - Alias property in 'aliases' node
- * @link: List node to link the structure in aliases_lookup list
- * @alias: Alias property name
- * @np: Pointer to device_node that the alias stands for
- * @id: Index value from end of alias name
- * @stem: Alias string without the index
- *
- * The structure represents one alias property of 'aliases' node as
- * an entry in aliases_lookup list.
- */
-struct alias_prop {
- struct list_head link;
- const char *alias;
- struct device_node *np;
- int id;
- char stem[0];
-};
+#include "of_private.h"
-static LIST_HEAD(aliases_lookup);
+LIST_HEAD(aliases_lookup);
struct device_node *of_allnodes;
EXPORT_SYMBOL(of_allnodes);
struct device_node *of_chosen;
struct device_node *of_aliases;
-static DEFINE_MUTEX(of_aliases_mutex);
+DEFINE_MUTEX(of_aliases_mutex);
/* use when traversing tree through the allnext, child, sibling,
* or parent members of struct device_node.
*/
-DEFINE_RWLOCK(devtree_lock);
+DEFINE_RAW_SPINLOCK(devtree_lock);
int of_n_addr_cells(struct device_node *np)
{
@@ -164,16 +147,14 @@ void of_node_put(struct device_node *node)
EXPORT_SYMBOL(of_node_put);
#endif /* CONFIG_OF_DYNAMIC */
-struct property *of_find_property(const struct device_node *np,
- const char *name,
- int *lenp)
+static struct property *__of_find_property(const struct device_node *np,
+ const char *name, int *lenp)
{
struct property *pp;
if (!np)
return NULL;
- read_lock(&devtree_lock);
for (pp = np->properties; pp; pp = pp->next) {
if (of_prop_cmp(pp->name, name) == 0) {
if (lenp)
@@ -181,7 +162,20 @@ struct property *of_find_property(const struct device_node *np,
break;
}
}
- read_unlock(&devtree_lock);
+
+ return pp;
+}
+
+struct property *of_find_property(const struct device_node *np,
+ const char *name,
+ int *lenp)
+{
+ struct property *pp;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ pp = __of_find_property(np, name, lenp);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return pp;
}
@@ -199,13 +193,13 @@ struct device_node *of_find_all_nodes(struct device_node *prev)
{
struct device_node *np;
- read_lock(&devtree_lock);
+ raw_spin_lock(&devtree_lock);
np = prev ? prev->allnext : of_allnodes;
for (; np != NULL; np = np->allnext)
if (of_node_get(np))
break;
of_node_put(prev);
- read_unlock(&devtree_lock);
+ raw_spin_unlock(&devtree_lock);
return np;
}
EXPORT_SYMBOL(of_find_all_nodes);
@@ -214,8 +208,20 @@ EXPORT_SYMBOL(of_find_all_nodes);
* Find a property with a given name for a given node
* and return the value.
*/
+static const void *__of_get_property(const struct device_node *np,
+ const char *name, int *lenp)
+{
+ struct property *pp = __of_find_property(np, name, lenp);
+
+ return pp ? pp->value : NULL;
+}
+
+/*
+ * Find a property with a given name for a given node
+ * and return the value.
+ */
const void *of_get_property(const struct device_node *np, const char *name,
- int *lenp)
+ int *lenp)
{
struct property *pp = of_find_property(np, name, lenp);
@@ -226,13 +232,13 @@ EXPORT_SYMBOL(of_get_property);
/** Checks if the given "compat" string matches one of the strings in
* the device's "compatible" property
*/
-int of_device_is_compatible(const struct device_node *device,
- const char *compat)
+static int __of_device_is_compatible(const struct device_node *device,
+ const char *compat)
{
const char* cp;
int cplen, l;
- cp = of_get_property(device, "compatible", &cplen);
+ cp = __of_get_property(device, "compatible", &cplen);
if (cp == NULL)
return 0;
while (cplen > 0) {
@@ -245,6 +251,21 @@ int of_device_is_compatible(const struct device_node *device,
return 0;
}
+
+/** Checks if the given "compat" string matches one of the strings in
+ * the device's "compatible" property
+ */
+int of_device_is_compatible(const struct device_node *device,
+ const char *compat)
+{
+ unsigned long flags;
+ int res;
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ res = __of_device_is_compatible(device, compat);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+ return res;
+}
EXPORT_SYMBOL(of_device_is_compatible);
/**
@@ -269,19 +290,19 @@ int of_machine_is_compatible(const char *compat)
EXPORT_SYMBOL(of_machine_is_compatible);
/**
- * of_device_is_available - check if a device is available for use
+ * __of_device_is_available - check if a device is available for use
*
- * @device: Node to check for availability
+ * @device: Node to check for availability, with locks already held
*
* Returns 1 if the status property is absent or set to "okay" or "ok",
* 0 otherwise
*/
-int of_device_is_available(const struct device_node *device)
+static int __of_device_is_available(const struct device_node *device)
{
const char *status;
int statlen;
- status = of_get_property(device, "status", &statlen);
+ status = __of_get_property(device, "status", &statlen);
if (status == NULL)
return 1;
@@ -292,6 +313,26 @@ int of_device_is_available(const struct device_node *device)
return 0;
}
+
+/**
+ * of_device_is_available - check if a device is available for use
+ *
+ * @device: Node to check for availability
+ *
+ * Returns 1 if the status property is absent or set to "okay" or "ok",
+ * 0 otherwise
+ */
+int of_device_is_available(const struct device_node *device)
+{
+ unsigned long flags;
+ int res;
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ res = __of_device_is_available(device);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+ return res;
+
+}
EXPORT_SYMBOL(of_device_is_available);
/**
@@ -304,13 +345,14 @@ EXPORT_SYMBOL(of_device_is_available);
struct device_node *of_get_parent(const struct device_node *node)
{
struct device_node *np;
+ unsigned long flags;
if (!node)
return NULL;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np = of_node_get(node->parent);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_get_parent);
@@ -329,14 +371,15 @@ EXPORT_SYMBOL(of_get_parent);
struct device_node *of_get_next_parent(struct device_node *node)
{
struct device_node *parent;
+ unsigned long flags;
if (!node)
return NULL;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
parent = of_node_get(node->parent);
of_node_put(node);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return parent;
}
@@ -352,14 +395,15 @@ struct device_node *of_get_next_child(const struct device_node *node,
struct device_node *prev)
{
struct device_node *next;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
next = prev ? prev->sibling : node->child;
for (; next; next = next->sibling)
if (of_node_get(next))
break;
of_node_put(prev);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return next;
}
EXPORT_SYMBOL(of_get_next_child);
@@ -377,16 +421,16 @@ struct device_node *of_get_next_available_child(const struct device_node *node,
{
struct device_node *next;
- read_lock(&devtree_lock);
+ raw_spin_lock(&devtree_lock);
next = prev ? prev->sibling : node->child;
for (; next; next = next->sibling) {
- if (!of_device_is_available(next))
+ if (!__of_device_is_available(next))
continue;
if (of_node_get(next))
break;
}
of_node_put(prev);
- read_unlock(&devtree_lock);
+ raw_spin_unlock(&devtree_lock);
return next;
}
EXPORT_SYMBOL(of_get_next_available_child);
@@ -424,14 +468,15 @@ EXPORT_SYMBOL(of_get_child_by_name);
struct device_node *of_find_node_by_path(const char *path)
{
struct device_node *np = of_allnodes;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
for (; np; np = np->allnext) {
if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
&& of_node_get(np))
break;
}
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_node_by_path);
@@ -451,15 +496,16 @@ struct device_node *of_find_node_by_name(struct device_node *from,
const char *name)
{
struct device_node *np;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext)
if (np->name && (of_node_cmp(np->name, name) == 0)
&& of_node_get(np))
break;
of_node_put(from);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_node_by_name);
@@ -480,15 +526,16 @@ struct device_node *of_find_node_by_type(struct device_node *from,
const char *type)
{
struct device_node *np;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext)
if (np->type && (of_node_cmp(np->type, type) == 0)
&& of_node_get(np))
break;
of_node_put(from);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_node_by_type);
@@ -511,18 +558,20 @@ struct device_node *of_find_compatible_node(struct device_node *from,
const char *type, const char *compatible)
{
struct device_node *np;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext) {
if (type
&& !(np->type && (of_node_cmp(np->type, type) == 0)))
continue;
- if (of_device_is_compatible(np, compatible) && of_node_get(np))
+ if (__of_device_is_compatible(np, compatible) &&
+ of_node_get(np))
break;
}
of_node_put(from);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_compatible_node);
@@ -544,8 +593,9 @@ struct device_node *of_find_node_with_property(struct device_node *from,
{
struct device_node *np;
struct property *pp;
+ unsigned long flags;
- read_lock(&devtree_lock);
+ 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) {
@@ -557,20 +607,14 @@ struct device_node *of_find_node_with_property(struct device_node *from,
}
out:
of_node_put(from);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_node_with_property);
-/**
- * of_match_node - Tell if an device_node has a matching of_match structure
- * @matches: array of of device match structures to search in
- * @node: the of device structure to match against
- *
- * Low level utility function used by device matching.
- */
-const struct of_device_id *of_match_node(const struct of_device_id *matches,
- const struct device_node *node)
+static
+const struct of_device_id *__of_match_node(const struct of_device_id *matches,
+ const struct device_node *node)
{
if (!matches)
return NULL;
@@ -584,14 +628,33 @@ const struct of_device_id *of_match_node(const struct of_device_id *matches,
match &= node->type
&& !strcmp(matches->type, node->type);
if (matches->compatible[0])
- match &= of_device_is_compatible(node,
- matches->compatible);
+ match &= __of_device_is_compatible(node,
+ matches->compatible);
if (match)
return matches;
matches++;
}
return NULL;
}
+
+/**
+ * of_match_node - Tell if an device_node has a matching of_match structure
+ * @matches: array of of device match structures to search in
+ * @node: the of device structure to match against
+ *
+ * Low level utility function used by device matching.
+ */
+const struct of_device_id *of_match_node(const struct of_device_id *matches,
+ const struct device_node *node)
+{
+ const struct of_device_id *match;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&devtree_lock, flags);
+ match = __of_match_node(matches, node);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
+ return match;
+}
EXPORT_SYMBOL(of_match_node);
/**
@@ -612,21 +675,24 @@ struct device_node *of_find_matching_node_and_match(struct device_node *from,
const struct of_device_id **match)
{
struct device_node *np;
+ const struct of_device_id *m;
+ unsigned long flags;
if (match)
*match = NULL;
- read_lock(&devtree_lock);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np = from ? from->allnext : of_allnodes;
for (; np; np = np->allnext) {
- if (of_match_node(matches, np) && of_node_get(np)) {
+ m = __of_match_node(matches, np);
+ if (m && of_node_get(np)) {
if (match)
- *match = matches;
+ *match = m;
break;
}
}
of_node_put(from);
- read_unlock(&devtree_lock);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return np;
}
EXPORT_SYMBOL(of_find_matching_node_and_match);
@@ -669,12 +735,12 @@ struct device_node *of_find_node_by_phandle(phandle handle)
{
struct device_node *np;
- read_lock(&devtree_lock);
+ raw_spin_lock(&devtree_lock);
for (np = of_allnodes; np; np = np->allnext)
if (np->phandle == handle)
break;
of_node_get(np);
- read_unlock(&devtree_lock);
+ raw_spin_unlock(&devtree_lock);
return np;
}
EXPORT_SYMBOL(of_find_node_by_phandle);
@@ -1025,12 +1091,13 @@ EXPORT_SYMBOL(of_parse_phandle);
* To get a device_node of the `node2' node you may call this:
* of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
*/
-int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
- const char *cells_name, int index,
- struct of_phandle_args *out_args)
+static int __of_parse_phandle_with_args(const struct device_node *np,
+ const char *list_name,
+ const char *cells_name, int index,
+ struct of_phandle_args *out_args)
{
const __be32 *list, *list_end;
- int size, cur_index = 0;
+ int rc = 0, size, cur_index = 0;
uint32_t count = 0;
struct device_node *node = NULL;
phandle phandle;
@@ -1043,6 +1110,7 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
/* Loop over the phandles until all the requested entry is found */
while (list < list_end) {
+ rc = -EINVAL;
count = 0;
/*
@@ -1059,13 +1127,13 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
if (!node) {
pr_err("%s: could not find phandle\n",
np->full_name);
- break;
+ goto err;
}
if (of_property_read_u32(node, cells_name, &count)) {
pr_err("%s: could not get %s for %s\n",
np->full_name, cells_name,
node->full_name);
- break;
+ goto err;
}
/*
@@ -1075,7 +1143,7 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
if (list + count > list_end) {
pr_err("%s: arguments longer than property\n",
np->full_name);
- break;
+ goto err;
}
}
@@ -1085,9 +1153,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
* index matches, then fill the out_args structure and return,
* or return -ENOENT for an empty entry.
*/
+ rc = -ENOENT;
if (cur_index == index) {
if (!phandle)
- return -ENOENT;
+ goto err;
if (out_args) {
int i;
@@ -1098,6 +1167,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
for (i = 0; i < count; i++)
out_args->args[i] = be32_to_cpup(list++);
}
+
+ /* Found it! return success */
+ if (node)
+ of_node_put(node);
return 0;
}
@@ -1107,13 +1180,51 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
cur_index++;
}
- /* Loop exited without finding a valid entry; return an error */
+ /*
+ * Unlock node before returning result; will be one of:
+ * -ENOENT : index is for empty phandle
+ * -EINVAL : parsing error on data
+ * [1..n] : Number of phandle (count mode; when index = -1)
+ */
+ rc = index < 0 ? cur_index : -ENOENT;
+ err:
if (node)
of_node_put(node);
- return -EINVAL;
+ return rc;
+}
+
+int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
+ const char *cells_name, int index,
+ struct of_phandle_args *out_args)
+{
+ if (index < 0)
+ return -EINVAL;
+ return __of_parse_phandle_with_args(np, list_name, cells_name, index, out_args);
}
EXPORT_SYMBOL(of_parse_phandle_with_args);
+/**
+ * of_count_phandle_with_args() - Find the number of phandles references in a property
+ * @np: pointer to a device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cells_name: property name that specifies phandles' arguments count
+ *
+ * Returns the number of phandle + argument tuples within a property. It
+ * is a typical pattern to encode a list of phandle and variable
+ * arguments into a single property. The number of arguments is encoded
+ * by a property in the phandle-target node. For example, a gpios
+ * property would contain a list of GPIO specifies consisting of a
+ * phandle and 1 or more arguments. The number of arguments are
+ * determined by the #gpio-cells property in the node pointed to by the
+ * phandle.
+ */
+int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
+ const char *cells_name)
+{
+ return __of_parse_phandle_with_args(np, list_name, cells_name, -1, NULL);
+}
+EXPORT_SYMBOL(of_count_phandle_with_args);
+
#if defined(CONFIG_OF_DYNAMIC)
static int of_property_notify(int action, struct device_node *np,
struct property *prop)
@@ -1146,18 +1257,18 @@ int of_add_property(struct device_node *np, struct property *prop)
return rc;
prop->next = NULL;
- write_lock_irqsave(&devtree_lock, flags);
+ raw_spin_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);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return -1;
}
next = &(*next)->next;
}
*next = prop;
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
#ifdef CONFIG_PROC_DEVICETREE
/* try to add to proc as well if it was initialized */
@@ -1187,7 +1298,7 @@ int of_remove_property(struct device_node *np, struct property *prop)
if (rc)
return rc;
- write_lock_irqsave(&devtree_lock, flags);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
next = &np->properties;
while (*next) {
if (*next == prop) {
@@ -1200,7 +1311,7 @@ int of_remove_property(struct device_node *np, struct property *prop)
}
next = &(*next)->next;
}
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
if (!found)
return -ENODEV;
@@ -1240,7 +1351,7 @@ int of_update_property(struct device_node *np, struct property *newprop)
if (!oldprop)
return of_add_property(np, newprop);
- write_lock_irqsave(&devtree_lock, flags);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
next = &np->properties;
while (*next) {
if (*next == oldprop) {
@@ -1254,7 +1365,7 @@ int of_update_property(struct device_node *np, struct property *newprop)
}
next = &(*next)->next;
}
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
if (!found)
return -ENODEV;
@@ -1327,12 +1438,12 @@ int of_attach_node(struct device_node *np)
if (rc)
return rc;
- write_lock_irqsave(&devtree_lock, flags);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
np->sibling = np->parent->child;
np->allnext = of_allnodes;
np->parent->child = np;
of_allnodes = np;
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
of_add_proc_dt_entry(np);
return 0;
@@ -1375,17 +1486,17 @@ int of_detach_node(struct device_node *np)
if (rc)
return rc;
- write_lock_irqsave(&devtree_lock, flags);
+ raw_spin_lock_irqsave(&devtree_lock, flags);
if (of_node_check_flag(np, OF_DETACHED)) {
/* someone already detached it */
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return rc;
}
parent = np->parent;
if (!parent) {
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
return rc;
}
@@ -1412,7 +1523,7 @@ int of_detach_node(struct device_node *np)
}
of_node_set_flag(np, OF_DETACHED);
- write_unlock_irqrestore(&devtree_lock, flags);
+ raw_spin_unlock_irqrestore(&devtree_lock, flags);
of_remove_proc_dt_entry(np);
return rc;