1 /*
2 * Copyright (C) 2009 Nokia Corporation
3 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
4 *
5 * Some code and ideas taken from drivers/video/omap/ driver
6 * by Imre Deak.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published by
10 * the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #define DSS_SUBSYS_NAME "DISPLAY"
22
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/jiffies.h>
26 #include <linux/platform_device.h>
27 #include <linux/of.h>
28
29 #include "omapdss.h"
30
omapdss_default_get_timings(struct omap_dss_device * dssdev,struct videomode * vm)31 static void omapdss_default_get_timings(struct omap_dss_device *dssdev,
32 struct videomode *vm)
33 {
34 *vm = dssdev->panel.vm;
35 }
36
37 static LIST_HEAD(panel_list);
38 static DEFINE_MUTEX(panel_list_mutex);
39 static int disp_num_counter;
40
omapdss_register_display(struct omap_dss_device * dssdev)41 int omapdss_register_display(struct omap_dss_device *dssdev)
42 {
43 struct omap_dss_driver *drv = dssdev->driver;
44 struct list_head *cur;
45 int id;
46
47 /*
48 * Note: this presumes that all displays either have an DT alias, or
49 * none has.
50 */
51 id = of_alias_get_id(dssdev->dev->of_node, "display");
52 if (id < 0)
53 id = disp_num_counter++;
54
55 snprintf(dssdev->alias, sizeof(dssdev->alias), "display%d", id);
56
57 /* Use 'label' property for name, if it exists */
58 of_property_read_string(dssdev->dev->of_node, "label", &dssdev->name);
59
60 if (dssdev->name == NULL)
61 dssdev->name = dssdev->alias;
62
63 if (drv && drv->get_timings == NULL)
64 drv->get_timings = omapdss_default_get_timings;
65
66 mutex_lock(&panel_list_mutex);
67 list_for_each(cur, &panel_list) {
68 struct omap_dss_device *ldev = list_entry(cur,
69 struct omap_dss_device,
70 panel_list);
71 if (strcmp(ldev->alias, dssdev->alias) > 0)
72 break;
73 }
74 list_add_tail(&dssdev->panel_list, cur);
75 mutex_unlock(&panel_list_mutex);
76 return 0;
77 }
78 EXPORT_SYMBOL(omapdss_register_display);
79
omapdss_unregister_display(struct omap_dss_device * dssdev)80 void omapdss_unregister_display(struct omap_dss_device *dssdev)
81 {
82 mutex_lock(&panel_list_mutex);
83 list_del(&dssdev->panel_list);
84 mutex_unlock(&panel_list_mutex);
85 }
86 EXPORT_SYMBOL(omapdss_unregister_display);
87
omapdss_component_is_display(struct device_node * node)88 bool omapdss_component_is_display(struct device_node *node)
89 {
90 struct omap_dss_device *dssdev;
91 bool found = false;
92
93 mutex_lock(&panel_list_mutex);
94 list_for_each_entry(dssdev, &panel_list, panel_list) {
95 if (dssdev->dev->of_node == node) {
96 found = true;
97 goto out;
98 }
99 }
100 out:
101 mutex_unlock(&panel_list_mutex);
102 return found;
103 }
104 EXPORT_SYMBOL(omapdss_component_is_display);
105
omap_dss_get_device(struct omap_dss_device * dssdev)106 struct omap_dss_device *omap_dss_get_device(struct omap_dss_device *dssdev)
107 {
108 if (!try_module_get(dssdev->owner))
109 return NULL;
110
111 if (get_device(dssdev->dev) == NULL) {
112 module_put(dssdev->owner);
113 return NULL;
114 }
115
116 return dssdev;
117 }
118 EXPORT_SYMBOL(omap_dss_get_device);
119
omap_dss_put_device(struct omap_dss_device * dssdev)120 void omap_dss_put_device(struct omap_dss_device *dssdev)
121 {
122 put_device(dssdev->dev);
123 module_put(dssdev->owner);
124 }
125 EXPORT_SYMBOL(omap_dss_put_device);
126
127 /*
128 * ref count of the found device is incremented.
129 * ref count of from-device is decremented.
130 */
omap_dss_get_next_device(struct omap_dss_device * from)131 struct omap_dss_device *omap_dss_get_next_device(struct omap_dss_device *from)
132 {
133 struct list_head *l;
134 struct omap_dss_device *dssdev;
135
136 mutex_lock(&panel_list_mutex);
137
138 if (list_empty(&panel_list)) {
139 dssdev = NULL;
140 goto out;
141 }
142
143 if (from == NULL) {
144 dssdev = list_first_entry(&panel_list, struct omap_dss_device,
145 panel_list);
146 omap_dss_get_device(dssdev);
147 goto out;
148 }
149
150 omap_dss_put_device(from);
151
152 list_for_each(l, &panel_list) {
153 dssdev = list_entry(l, struct omap_dss_device, panel_list);
154 if (dssdev == from) {
155 if (list_is_last(l, &panel_list)) {
156 dssdev = NULL;
157 goto out;
158 }
159
160 dssdev = list_entry(l->next, struct omap_dss_device,
161 panel_list);
162 omap_dss_get_device(dssdev);
163 goto out;
164 }
165 }
166
167 WARN(1, "'from' dssdev not found\n");
168
169 dssdev = NULL;
170 out:
171 mutex_unlock(&panel_list_mutex);
172 return dssdev;
173 }
174 EXPORT_SYMBOL(omap_dss_get_next_device);
175
