From: Mathieu Poirier Date: Wed, 8 Oct 2014 18:02:38 +0000 (-0600) Subject: of: back-porting v4l2 graph bindings X-Git-Tag: firefly_0821_release~3680^2~19^2~3^2~2^2~21 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2990c832abedddddce89e9633cbcbceb355feede;p=firefly-linux-kernel-4.4.55.git of: back-porting v4l2 graph bindings This patch is back-porting the generic _portion_ of fd9fdb78a9bf85b94fb2190c82ff280c8f8375cc to 3.10 Signed-off-by: Mathieu Poirier --- diff --git a/drivers/of/base.c b/drivers/of/base.c index a6f584a7f4a1..4caad01b6fec 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -1703,3 +1703,123 @@ const char *of_prop_next_string(struct property *prop, const char *cur) return curv; } EXPORT_SYMBOL_GPL(of_prop_next_string); + +/** + * 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); diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h new file mode 100644 index 000000000000..3bbeb609a360 --- /dev/null +++ b/include/linux/of_graph.h @@ -0,0 +1,46 @@ +/* + * OF graph binding parsing helpers + * + * Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd. + * Author: Sylwester Nawrocki + * + * Copyright (C) 2012 Renesas Electronics Corp. + * Author: Guennadi Liakhovetski + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + */ +#ifndef __LINUX_OF_GRAPH_H +#define __LINUX_OF_GRAPH_H + +#ifdef CONFIG_OF +struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, + struct device_node *previous); +struct device_node *of_graph_get_remote_port_parent( + const struct device_node *node); +struct device_node *of_graph_get_remote_port(const struct device_node *node); +#else + +static inline struct device_node *of_graph_get_next_endpoint( + const struct device_node *parent, + struct device_node *previous) +{ + return NULL; +} + +static inline struct device_node *of_graph_get_remote_port_parent( + const struct device_node *node) +{ + return NULL; +} + +static inline struct device_node *of_graph_get_remote_port( + const struct device_node *node) +{ + return NULL; +} + +#endif /* CONFIG_OF */ + +#endif /* __LINUX_OF_GRAPH_H */