tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2013 Texas Instruments
3 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 */
14
15#include <linux/device.h>
16#include <linux/err.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/seq_file.h>
20
21#include <video/omapdss.h>
22
23struct device_node *
24omapdss_of_get_next_port(const struct device_node *parent,
25 struct device_node *prev)
26{
27 struct device_node *port = NULL;
28
29 if (!parent)
30 return NULL;
31
32 if (!prev) {
33 struct device_node *ports;
34 /*
35 * It's the first call, we have to find a port subnode
36 * within this node or within an optional 'ports' node.
37 */
38 ports = of_get_child_by_name(parent, "ports");
39 if (ports)
40 parent = ports;
41
42 port = of_get_child_by_name(parent, "port");
43
44 /* release the 'ports' node */
45 of_node_put(ports);
46 } else {
47 struct device_node *ports;
48
49 ports = of_get_parent(prev);
50 if (!ports)
51 return NULL;
52
53 do {
54 port = of_get_next_child(ports, prev);
55 if (!port) {
56 of_node_put(ports);
57 return NULL;
58 }
59 prev = port;
60 } while (of_node_cmp(port->name, "port") != 0);
61 }
62
63 return port;
64}
65EXPORT_SYMBOL_GPL(omapdss_of_get_next_port);
66
67struct device_node *
68omapdss_of_get_next_endpoint(const struct device_node *parent,
69 struct device_node *prev)
70{
71 struct device_node *ep = NULL;
72
73 if (!parent)
74 return NULL;
75
76 do {
77 ep = of_get_next_child(parent, prev);
78 if (!ep)
79 return NULL;
80 prev = ep;
81 } while (of_node_cmp(ep->name, "endpoint") != 0);
82
83 return ep;
84}
85EXPORT_SYMBOL_GPL(omapdss_of_get_next_endpoint);
86
87static struct device_node *
88omapdss_of_get_remote_device_node(const struct device_node *node)
89{
90 struct device_node *np;
91 int i;
92
93 np = of_parse_phandle(node, "remote-endpoint", 0);
94
95 if (!np)
96 return NULL;
97
98 np = of_get_next_parent(np);
99
100 for (i = 0; i < 3 && np; ++i) {
101 struct property *prop;
102
103 prop = of_find_property(np, "compatible", NULL);
104
105 if (prop)
106 return np;
107
108 np = of_get_next_parent(np);
109 }
110
111 return NULL;
112}
113
114struct device_node *
115omapdss_of_get_first_endpoint(const struct device_node *parent)
116{
117 struct device_node *port, *ep;
118
119 port = omapdss_of_get_next_port(parent, NULL);
120
121 if (!port)
122 return NULL;
123
124 ep = omapdss_of_get_next_endpoint(port, NULL);
125
126 of_node_put(port);
127
128 return ep;
129}
130EXPORT_SYMBOL_GPL(omapdss_of_get_first_endpoint);
131
132struct omap_dss_device *
133omapdss_of_find_source_for_first_ep(struct device_node *node)
134{
135 struct device_node *ep;
136 struct device_node *src_node;
137 struct omap_dss_device *src;
138
139 ep = omapdss_of_get_first_endpoint(node);
140 if (!ep)
141 return ERR_PTR(-EINVAL);
142
143 src_node = omapdss_of_get_remote_device_node(ep);
144
145 of_node_put(ep);
146
147 if (!src_node)
148 return ERR_PTR(-EINVAL);
149
150 src = omap_dss_find_output_by_node(src_node);
151
152 of_node_put(src_node);
153
154 if (!src)
155 return ERR_PTR(-EPROBE_DEFER);
156
157 return src;
158}
159EXPORT_SYMBOL_GPL(omapdss_of_find_source_for_first_ep);