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 "omapdss.h"
22#include "dss.h"
23
24struct device_node *
25omapdss_of_get_next_port(const struct device_node *parent,
26 struct device_node *prev)
27{
28 struct device_node *port = NULL;
29
30 if (!parent)
31 return NULL;
32
33 if (!prev) {
34 struct device_node *ports;
35 /*
36 * It's the first call, we have to find a port subnode
37 * within this node or within an optional 'ports' node.
38 */
39 ports = of_get_child_by_name(parent, "ports");
40 if (ports)
41 parent = ports;
42
43 port = of_get_child_by_name(parent, "port");
44
45 /* release the 'ports' node */
46 of_node_put(ports);
47 } else {
48 struct device_node *ports;
49
50 ports = of_get_parent(prev);
51 if (!ports)
52 return NULL;
53
54 do {
55 port = of_get_next_child(ports, prev);
56 if (!port) {
57 of_node_put(ports);
58 return NULL;
59 }
60 prev = port;
61 } while (of_node_cmp(port->name, "port") != 0);
62
63 of_node_put(ports);
64 }
65
66 return port;
67}
68EXPORT_SYMBOL_GPL(omapdss_of_get_next_port);
69
70struct device_node *
71omapdss_of_get_next_endpoint(const struct device_node *parent,
72 struct device_node *prev)
73{
74 struct device_node *ep = NULL;
75
76 if (!parent)
77 return NULL;
78
79 do {
80 ep = of_get_next_child(parent, prev);
81 if (!ep)
82 return NULL;
83 prev = ep;
84 } while (of_node_cmp(ep->name, "endpoint") != 0);
85
86 return ep;
87}
88EXPORT_SYMBOL_GPL(omapdss_of_get_next_endpoint);
89
90struct device_node *dss_of_port_get_parent_device(struct device_node *port)
91{
92 struct device_node *np;
93 int i;
94
95 if (!port)
96 return NULL;
97
98 np = of_get_parent(port);
99
100 for (i = 0; i < 2 && 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
114u32 dss_of_port_get_port_number(struct device_node *port)
115{
116 int r;
117 u32 reg;
118
119 r = of_property_read_u32(port, "reg", ®);
120 if (r)
121 reg = 0;
122
123 return reg;
124}
125
126static struct device_node *omapdss_of_get_remote_port(const struct device_node *node)
127{
128 struct device_node *np;
129
130 np = of_parse_phandle(node, "remote-endpoint", 0);
131 if (!np)
132 return NULL;
133
134 np = of_get_next_parent(np);
135
136 return np;
137}
138
139struct device_node *
140omapdss_of_get_first_endpoint(const struct device_node *parent)
141{
142 struct device_node *port, *ep;
143
144 port = omapdss_of_get_next_port(parent, NULL);
145
146 if (!port)
147 return NULL;
148
149 ep = omapdss_of_get_next_endpoint(port, NULL);
150
151 of_node_put(port);
152
153 return ep;
154}
155EXPORT_SYMBOL_GPL(omapdss_of_get_first_endpoint);
156
157struct omap_dss_device *
158omapdss_of_find_source_for_first_ep(struct device_node *node)
159{
160 struct device_node *ep;
161 struct device_node *src_port;
162 struct omap_dss_device *src;
163
164 ep = omapdss_of_get_first_endpoint(node);
165 if (!ep)
166 return ERR_PTR(-EINVAL);
167
168 src_port = omapdss_of_get_remote_port(ep);
169 if (!src_port) {
170 of_node_put(ep);
171 return ERR_PTR(-EINVAL);
172 }
173
174 of_node_put(ep);
175
176 src = omap_dss_find_output_by_port_node(src_port);
177
178 of_node_put(src_port);
179
180 return src ? src : ERR_PTR(-EPROBE_DEFER);
181}
182EXPORT_SYMBOL_GPL(omapdss_of_find_source_for_first_ep);