xref: /openbmc/linux/drivers/gpu/drm/drm_panel.c (revision a8fe58ce)
1 /*
2  * Copyright (C) 2013, NVIDIA Corporation.  All rights reserved.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sub license,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the
12  * next paragraph) shall be included in all copies or substantial portions
13  * of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/err.h>
25 #include <linux/module.h>
26 
27 #include <drm/drm_crtc.h>
28 #include <drm/drm_panel.h>
29 
30 static DEFINE_MUTEX(panel_lock);
31 static LIST_HEAD(panel_list);
32 
33 void drm_panel_init(struct drm_panel *panel)
34 {
35 	INIT_LIST_HEAD(&panel->list);
36 }
37 EXPORT_SYMBOL(drm_panel_init);
38 
39 int drm_panel_add(struct drm_panel *panel)
40 {
41 	mutex_lock(&panel_lock);
42 	list_add_tail(&panel->list, &panel_list);
43 	mutex_unlock(&panel_lock);
44 
45 	return 0;
46 }
47 EXPORT_SYMBOL(drm_panel_add);
48 
49 void drm_panel_remove(struct drm_panel *panel)
50 {
51 	mutex_lock(&panel_lock);
52 	list_del_init(&panel->list);
53 	mutex_unlock(&panel_lock);
54 }
55 EXPORT_SYMBOL(drm_panel_remove);
56 
57 int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
58 {
59 	if (panel->connector)
60 		return -EBUSY;
61 
62 	panel->connector = connector;
63 	panel->drm = connector->dev;
64 
65 	return 0;
66 }
67 EXPORT_SYMBOL(drm_panel_attach);
68 
69 int drm_panel_detach(struct drm_panel *panel)
70 {
71 	panel->connector = NULL;
72 	panel->drm = NULL;
73 
74 	return 0;
75 }
76 EXPORT_SYMBOL(drm_panel_detach);
77 
78 #ifdef CONFIG_OF
79 struct drm_panel *of_drm_find_panel(struct device_node *np)
80 {
81 	struct drm_panel *panel;
82 
83 	mutex_lock(&panel_lock);
84 
85 	list_for_each_entry(panel, &panel_list, list) {
86 		if (panel->dev->of_node == np) {
87 			mutex_unlock(&panel_lock);
88 			return panel;
89 		}
90 	}
91 
92 	mutex_unlock(&panel_lock);
93 	return NULL;
94 }
95 EXPORT_SYMBOL(of_drm_find_panel);
96 #endif
97 
98 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
99 MODULE_DESCRIPTION("DRM panel infrastructure");
100 MODULE_LICENSE("GPL and additional rights");
101