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authorMark Brown <broonie@kernel.org>2015-01-09 18:23:25 +0000
committerMark Brown <broonie@kernel.org>2015-01-09 18:23:25 +0000
commit7368857a8eed5144e56e65713970764ef0f2f0b8 (patch)
tree2c80643782eb6f3dd18bd672b555781556b0cafc /drivers/of/base.c
parent297e25caff999eeccf24b19e62388450763af15d (diff)
parent025f8da59f0a0415c9f4033dc010d0607c81b6b3 (diff)
Merge remote-tracking branch 'lsk/v3.14/topic/coresight' into linux-linaro-lsk-v3.14
Conflicts: drivers/Makefile
Diffstat (limited to 'drivers/of/base.c')
-rw-r--r--drivers/of/base.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 3935614274eb..ac26e58e3686 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -21,6 +21,7 @@
#include <linux/cpu.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_graph.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
@@ -1938,3 +1939,154 @@ struct device_node *of_find_next_cache_node(const struct device_node *np)
return NULL;
}
+
+/**
+ * of_graph_parse_endpoint() - parse common endpoint node properties
+ * @node: pointer to endpoint device_node
+ * @endpoint: pointer to the OF endpoint data structure
+ *
+ * The caller should hold a reference to @node.
+ */
+int of_graph_parse_endpoint(const struct device_node *node,
+ struct of_endpoint *endpoint)
+{
+ struct device_node *port_node = of_get_parent(node);
+
+ WARN_ONCE(!port_node, "%s(): endpoint %s has no parent node\n",
+ __func__, node->full_name);
+
+ memset(endpoint, 0, sizeof(*endpoint));
+
+ endpoint->local_node = node;
+ /*
+ * It doesn't matter whether the two calls below succeed.
+ * If they don't then the default value 0 is used.
+ */
+ of_property_read_u32(port_node, "reg", &endpoint->port);
+ of_property_read_u32(node, "reg", &endpoint->id);
+
+ of_node_put(port_node);
+
+ return 0;
+}
+EXPORT_SYMBOL(of_graph_parse_endpoint);
+
+/**
+ * of_graph_get_next_endpoint() - get next endpoint node
+ * @parent: pointer to the parent device node
+ * @prev: previous endpoint node, or NULL to get first
+ *
+ * Return: An 'endpoint' node pointer with refcount incremented. Refcount
+ * of the passed @prev node is not decremented, the caller have to use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
+ struct device_node *prev)
+{
+ struct device_node *endpoint;
+ struct device_node *port;
+
+ if (!parent)
+ return NULL;
+
+ /*
+ * Start by locating the port node. If no previous endpoint is specified
+ * search for the first port node, otherwise get the previous endpoint
+ * parent port node.
+ */
+ if (!prev) {
+ struct device_node *node;
+
+ node = of_get_child_by_name(parent, "ports");
+ if (node)
+ parent = node;
+
+ port = of_get_child_by_name(parent, "port");
+ of_node_put(node);
+
+ if (!port) {
+ pr_err("%s(): no port node found in %s\n",
+ __func__, parent->full_name);
+ return NULL;
+ }
+ } else {
+ port = of_get_parent(prev);
+ if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+ __func__, prev->full_name))
+ return NULL;
+
+ /*
+ * Avoid dropping prev node refcount to 0 when getting the next
+ * child below.
+ */
+ of_node_get(prev);
+ }
+
+ while (1) {
+ /*
+ * Now that we have a port node, get the next endpoint by
+ * getting the next child. If the previous endpoint is NULL this
+ * will return the first child.
+ */
+ endpoint = of_get_next_child(port, prev);
+ if (endpoint) {
+ of_node_put(port);
+ return endpoint;
+ }
+
+ /* No more endpoints under this port, try the next one. */
+ prev = NULL;
+
+ do {
+ port = of_get_next_child(parent, port);
+ if (!port)
+ return NULL;
+ } while (of_node_cmp(port->name, "port"));
+ }
+}
+EXPORT_SYMBOL(of_graph_get_next_endpoint);
+
+/**
+ * of_graph_get_remote_port_parent() - get remote port's parent node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote device node associated with remote endpoint node linked
+ * to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port_parent(
+ const struct device_node *node)
+{
+ struct device_node *np;
+ unsigned int depth;
+
+ /* Get remote endpoint node. */
+ np = of_parse_phandle(node, "remote-endpoint", 0);
+
+ /* Walk 3 levels up only if there is 'ports' node. */
+ for (depth = 3; depth && np; depth--) {
+ np = of_get_next_parent(np);
+ if (depth == 2 && of_node_cmp(np->name, "ports"))
+ break;
+ }
+ return np;
+}
+EXPORT_SYMBOL(of_graph_get_remote_port_parent);
+
+/**
+ * of_graph_get_remote_port() - get remote port node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: Remote port node associated with remote endpoint node linked
+ * to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_port(const struct device_node *node)
+{
+ struct device_node *np;
+
+ /* Get remote endpoint node. */
+ np = of_parse_phandle(node, "remote-endpoint", 0);
+ if (!np)
+ return NULL;
+ return of_get_next_parent(np);
+}
+EXPORT_SYMBOL(of_graph_get_remote_port);