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