From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
We have endpoint base functions
- of_graph_get_next_endpoint()
- of_graph_get_endpoint_count()
- for_each_endpoint_of_node()
for_each_endpoint_of_node() loop finds endpoint.
ports {
port@0 {
(1) endpoint {...};
};
port@1 {
(2) endpoint {...};
};
...
};
In above case, for_each_endpoint_of_node() loop
finds endpoint as (1) -> (2) -> ...
If we want to get port@0 -> port@1 -> ...
instead of endpoint, we need do like below
for_each_endpoint_of_node(node, endpoint) {
port = of_get_parent(endpoint);
...
}
But port might have multi endpoints.
ports {
port@0 {
(1) endpoint@0 {...};
(2) endpoint@1 {...};
};
port@1 {
(3) endpoint {...};
};
...
};
In such case, people want to have "port base" loop
instead of "endpoints base" loop.
This patch adds such functions/macros.
Link: https://lore.kernel.org/r/87pn29pc5w.wl-kuninori.morimoto.gx@xxxxxxxxxxx
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
---
drivers/of/property.c | 69 ++++++++++++++++++++++++++++++++++------
include/linux/of_graph.h | 14 ++++++++
2 files changed, 73 insertions(+), 10 deletions(-)
diff --git a/drivers/of/property.c b/drivers/of/property.c
index 6c028632f425..bf3bdeeba2f9 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -650,15 +650,7 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
* 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);
-
+ port = of_graph_get_next_port(parent, NULL);
if (!port) {
pr_err("graph: no port node found in %pOF\n", parent);
return NULL;
@@ -685,14 +677,59 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
/* No more endpoints under this port, try the next one. */
prev = NULL;
+ port = of_graph_get_next_port(parent, port);
+ if (!port)
+ return NULL;
+ }
+}
+EXPORT_SYMBOL(of_graph_get_next_endpoint);
+
+/**
+ * of_graph_get_next_port() - get next port node
+ * @parent: pointer to the parent device node
+ * @prev: previous port node, or NULL to get first
+ *
+ * Return: An 'port' node pointer with refcount incremented. Refcount
+ * of the passed @prev node is decremented.
+ */
+struct device_node *of_graph_get_next_port(const struct device_node *parent,
+ struct device_node *prev)
+{
+ struct device_node *port = prev;
+
+ 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 (!port) {
+ 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("graph: no port node found in %pOF\n", parent);
+ return NULL;
+ }
+ } else {
do {
port = of_get_next_child(parent, port);
if (!port)
return NULL;
} while (!of_node_name_eq(port, "port"));
}
+
+ return port;
}
-EXPORT_SYMBOL(of_graph_get_next_endpoint);
+EXPORT_SYMBOL(of_graph_get_next_port);
/**
* of_graph_get_endpoint_by_regs() - get endpoint node of specific identifiers
@@ -819,6 +856,18 @@ int of_graph_get_endpoint_count(const struct device_node *np)
}
EXPORT_SYMBOL(of_graph_get_endpoint_count);
+int of_graph_get_port_count(const struct device_node *np)
+{
+ struct device_node *port;
+ int num = 0;
+
+ for_each_port_of_node(np, port)
+ num++;
+
+ return num;
+}
+EXPORT_SYMBOL(of_graph_get_port_count);
+
/**
* of_graph_get_remote_node() - get remote parent device_node for given port/endpoint
* @node: pointer to parent device_node containing graph port/endpoint
diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h
index 4d7756087b6b..8cd3bd674ebd 100644
--- a/include/linux/of_graph.h
+++ b/include/linux/of_graph.h
@@ -26,6 +26,17 @@ struct of_endpoint {
const struct device_node *local_node;
};
+/**
+ * for_each_port_of_node - iterate over every port in a device node
+ * @parent: parent device node containing ports and port
+ * @child: loop variable pointing to the current port node
+ *
+ * When breaking out of the loop, of_node_put(child) has to be called manually.
+ */
+#define for_each_port_of_node(parent, child) \
+ for (child = of_graph_get_next_port(parent, NULL); child != NULL; \
+ child = of_graph_get_next_port(parent, child))
+
/**
* for_each_endpoint_of_node - iterate over every endpoint in a device node
* @parent: parent device node containing ports and endpoints
@@ -41,8 +52,11 @@ struct of_endpoint {
bool of_graph_is_present(const struct device_node *node);
int of_graph_parse_endpoint(const struct device_node *node,
struct of_endpoint *endpoint);
+int of_graph_get_port_count(const struct device_node *np);
int of_graph_get_endpoint_count(const struct device_node *np);
struct device_node *of_graph_get_port_by_id(struct device_node *node, u32 id);
+struct device_node *of_graph_get_next_port(const struct device_node *parent,
+ struct device_node *previous);
struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
struct device_node *previous);
struct device_node *of_graph_get_endpoint_by_regs(
--
2.25.1
