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/of_graph.h>
20 #include <linux/seq_file.h>
21
22 #include <video/omapfb_dss.h>
23
24 #include "dss.h"
25
26 struct device_node *
omapdss_of_get_next_port(const struct device_node * parent,struct device_node * prev)27 omapdss_of_get_next_port(const struct device_node *parent,
28 struct device_node *prev)
29 {
30 struct device_node *port = NULL;
31
32 if (!parent)
33 return NULL;
34
35 if (!prev) {
36 struct device_node *ports;
37 /*
38 * It's the first call, we have to find a port subnode
39 * within this node or within an optional 'ports' node.
40 */
41 ports = of_get_child_by_name(parent, "ports");
42 if (ports)
43 parent = ports;
44
45 port = of_get_child_by_name(parent, "port");
46
47 /* release the 'ports' node */
48 of_node_put(ports);
49 } else {
50 struct device_node *ports;
51
52 ports = of_get_parent(prev);
53 if (!ports)
54 return NULL;
55
56 do {
57 port = of_get_next_child(ports, prev);
58 if (!port) {
59 of_node_put(ports);
60 return NULL;
61 }
62 prev = port;
63 } while (of_node_cmp(port->name, "port") != 0);
64
65 of_node_put(ports);
66 }
67
68 return port;
69 }
70 EXPORT_SYMBOL_GPL(omapdss_of_get_next_port);
71
72 struct device_node *
omapdss_of_get_next_endpoint(const struct device_node * parent,struct device_node * prev)73 omapdss_of_get_next_endpoint(const struct device_node *parent,
74 struct device_node *prev)
75 {
76 struct device_node *ep = NULL;
77
78 if (!parent)
79 return NULL;
80
81 do {
82 ep = of_get_next_child(parent, prev);
83 if (!ep)
84 return NULL;
85 prev = ep;
86 } while (of_node_cmp(ep->name, "endpoint") != 0);
87
88 return ep;
89 }
90 EXPORT_SYMBOL_GPL(omapdss_of_get_next_endpoint);
91
dss_of_port_get_parent_device(struct device_node * port)92 struct device_node *dss_of_port_get_parent_device(struct device_node *port)
93 {
94 struct device_node *np;
95 int i;
96
97 if (!port)
98 return NULL;
99
100 np = of_get_parent(port);
101
102 for (i = 0; i < 2 && np; ++i) {
103 struct property *prop;
104
105 prop = of_find_property(np, "compatible", NULL);
106
107 if (prop)
108 return np;
109
110 np = of_get_next_parent(np);
111 }
112
113 return NULL;
114 }
115
dss_of_port_get_port_number(struct device_node * port)116 u32 dss_of_port_get_port_number(struct device_node *port)
117 {
118 int r;
119 u32 reg;
120
121 r = of_property_read_u32(port, "reg", ®);
122 if (r)
123 reg = 0;
124
125 return reg;
126 }
127
omapdss_of_get_remote_port(const struct device_node * node)128 static struct device_node *omapdss_of_get_remote_port(const struct device_node *node)
129 {
130 struct device_node *np;
131
132 np = of_graph_get_remote_endpoint(node);
133 if (!np)
134 return NULL;
135
136 np = of_get_next_parent(np);
137
138 return np;
139 }
140
141 struct device_node *
omapdss_of_get_first_endpoint(const struct device_node * parent)142 omapdss_of_get_first_endpoint(const struct device_node *parent)
143 {
144 struct device_node *port, *ep;
145
146 port = omapdss_of_get_next_port(parent, NULL);
147
148 if (!port)
149 return NULL;
150
151 ep = omapdss_of_get_next_endpoint(port, NULL);
152
153 of_node_put(port);
154
155 return ep;
156 }
157 EXPORT_SYMBOL_GPL(omapdss_of_get_first_endpoint);
158
159 struct omap_dss_device *
omapdss_of_find_source_for_first_ep(struct device_node * node)160 omapdss_of_find_source_for_first_ep(struct device_node *node)
161 {
162 struct device_node *ep;
163 struct device_node *src_port;
164 struct omap_dss_device *src;
165
166 ep = omapdss_of_get_first_endpoint(node);
167 if (!ep)
168 return ERR_PTR(-EINVAL);
169
170 src_port = omapdss_of_get_remote_port(ep);
171 if (!src_port) {
172 of_node_put(ep);
173 return ERR_PTR(-EINVAL);
174 }
175
176 of_node_put(ep);
177
178 src = omap_dss_find_output_by_port_node(src_port);
179
180 of_node_put(src_port);
181
182 return src ? src : ERR_PTR(-EPROBE_DEFER);
183 }
184 EXPORT_SYMBOL_GPL(omapdss_of_find_source_for_first_ep);
185