xref: /openbmc/linux/drivers/gpu/drm/omapdrm/dss/base.c (revision d3541ca81dbddeefa0c42df448211a9dbaef0843)
1 /*
2  * OMAP Display Subsystem Base
3  *
4  * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_graph.h>
20 #include <linux/list.h>
21 
22 #include "dss.h"
23 #include "omapdss.h"
24 
25 static struct dss_device *dss_device;
26 
27 static struct list_head omapdss_comp_list;
28 
29 struct omapdss_comp_node {
30 	struct list_head list;
31 	struct device_node *node;
32 	bool dss_core_component;
33 };
34 
35 struct dss_device *omapdss_get_dss(void)
36 {
37 	return dss_device;
38 }
39 EXPORT_SYMBOL(omapdss_get_dss);
40 
41 void omapdss_set_dss(struct dss_device *dss)
42 {
43 	dss_device = dss;
44 }
45 EXPORT_SYMBOL(omapdss_set_dss);
46 
47 const struct dispc_ops *dispc_get_ops(struct dss_device *dss)
48 {
49 	return dss->dispc_ops;
50 }
51 EXPORT_SYMBOL(dispc_get_ops);
52 
53 static bool omapdss_list_contains(const struct device_node *node)
54 {
55 	struct omapdss_comp_node *comp;
56 
57 	list_for_each_entry(comp, &omapdss_comp_list, list) {
58 		if (comp->node == node)
59 			return true;
60 	}
61 
62 	return false;
63 }
64 
65 static void omapdss_walk_device(struct device *dev, struct device_node *node,
66 				bool dss_core)
67 {
68 	struct device_node *n;
69 	struct omapdss_comp_node *comp = devm_kzalloc(dev, sizeof(*comp),
70 						      GFP_KERNEL);
71 
72 	if (comp) {
73 		comp->node = node;
74 		comp->dss_core_component = dss_core;
75 		list_add(&comp->list, &omapdss_comp_list);
76 	}
77 
78 	/*
79 	 * of_graph_get_remote_port_parent() prints an error if there is no
80 	 * port/ports node. To avoid that, check first that there's the node.
81 	 */
82 	n = of_get_child_by_name(node, "ports");
83 	if (!n)
84 		n = of_get_child_by_name(node, "port");
85 	if (!n)
86 		return;
87 
88 	of_node_put(n);
89 
90 	n = NULL;
91 	while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
92 		struct device_node *pn = of_graph_get_remote_port_parent(n);
93 
94 		if (!pn)
95 			continue;
96 
97 		if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
98 			of_node_put(pn);
99 			continue;
100 		}
101 
102 		omapdss_walk_device(dev, pn, false);
103 	}
104 }
105 
106 void omapdss_gather_components(struct device *dev)
107 {
108 	struct device_node *child;
109 
110 	INIT_LIST_HEAD(&omapdss_comp_list);
111 
112 	omapdss_walk_device(dev, dev->of_node, true);
113 
114 	for_each_available_child_of_node(dev->of_node, child) {
115 		if (!of_find_property(child, "compatible", NULL))
116 			continue;
117 
118 		omapdss_walk_device(dev, child, true);
119 	}
120 }
121 EXPORT_SYMBOL(omapdss_gather_components);
122 
123 static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)
124 {
125 	if (comp->dss_core_component)
126 		return true;
127 	if (omapdss_component_is_display(comp->node))
128 		return true;
129 	if (omapdss_component_is_output(comp->node))
130 		return true;
131 
132 	return false;
133 }
134 
135 bool omapdss_stack_is_ready(void)
136 {
137 	struct omapdss_comp_node *comp;
138 
139 	list_for_each_entry(comp, &omapdss_comp_list, list) {
140 		if (!omapdss_component_is_loaded(comp))
141 			return false;
142 	}
143 
144 	return true;
145 }
146 EXPORT_SYMBOL(omapdss_stack_is_ready);
147 
148 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
149 MODULE_DESCRIPTION("OMAP Display Subsystem Base");
150 MODULE_LICENSE("GPL v2");
151