linux-next/include/linux/of_graph.h
Hyungwon Hwang 8ccd0d0ca0 of: add helper for getting endpoint node of specific identifiers
When there are multiple ports or multiple endpoints in a port, they have to be
distinguished by the value of reg property. It is common. The drivers can get
the specific endpoint in the specific port via this function. Now the drivers
have to implement this code in themselves or have to force the order of dt nodes
to get the right node.

Signed-off-by: Hyungwon Hwang <human.hwang@samsung.com>
Acked-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
2015-06-22 19:56:51 +09:00

95 lines
2.7 KiB
C

/*
* OF graph binding parsing helpers
*
* Copyright (C) 2012 - 2013 Samsung Electronics Co., Ltd.
* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
*
* Copyright (C) 2012 Renesas Electronics Corp.
* Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
*
* 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
#include <linux/types.h>
/**
* struct of_endpoint - the OF graph endpoint data structure
* @port: identifier (value of reg property) of a port this endpoint belongs to
* @id: identifier (value of reg property) of this endpoint
* @local_node: pointer to device_node of this endpoint
*/
struct of_endpoint {
unsigned int port;
unsigned int id;
const struct device_node *local_node;
};
/**
* for_each_endpoint_of_node - iterate over every endpoint in a device node
* @parent: parent device node containing ports and endpoints
* @child: loop variable pointing to the current endpoint node
*
* When breaking out of the loop, of_node_put(child) has to be called manually.
*/
#define for_each_endpoint_of_node(parent, child) \
for (child = of_graph_get_next_endpoint(parent, NULL); child != NULL; \
child = of_graph_get_next_endpoint(parent, child))
#ifdef CONFIG_OF
int of_graph_parse_endpoint(const struct device_node *node,
struct of_endpoint *endpoint);
struct device_node *of_graph_get_port_by_id(struct device_node *node, u32 id);
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(
const struct device_node *parent, int port_reg, int reg);
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 int of_graph_parse_endpoint(const struct device_node *node,
struct of_endpoint *endpoint)
{
return -ENOSYS;
}
static inline struct device_node *of_graph_get_port_by_id(
struct device_node *node, u32 id)
{
return NULL;
}
static inline struct device_node *of_graph_get_next_endpoint(
const struct device_node *parent,
struct device_node *previous)
{
return NULL;
}
struct device_node *of_graph_get_endpoint_by_regs(
const struct device_node *parent, int port_reg, int reg)
{
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 */