1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
/*
* Copyright (C) 2013, NVIDIA Corporation. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sub license,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef __DRM_PANEL_H__
#define __DRM_PANEL_H__
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/list.h>
struct backlight_device;
struct device_node;
struct drm_connector;
struct drm_device;
struct drm_panel;
struct display_timing;
/**
* struct drm_panel_funcs - perform operations on a given panel
*
* The .prepare() function is typically called before the display controller
* starts to transmit video data. Panel drivers can use this to turn the panel
* on and wait for it to become ready. If additional configuration is required
* (via a control bus such as I2C, SPI or DSI for example) this is a good time
* to do that.
*
* After the display controller has started transmitting video data, it's safe
* to call the .enable() function. This will typically enable the backlight to
* make the image on screen visible. Some panels require a certain amount of
* time or frames before the image is displayed. This function is responsible
* for taking this into account before enabling the backlight to avoid visual
* glitches.
*
* Before stopping video transmission from the display controller it can be
* necessary to turn off the panel to avoid visual glitches. This is done in
* the .disable() function. Analogously to .enable() this typically involves
* turning off the backlight and waiting for some time to make sure no image
* is visible on the panel. It is then safe for the display controller to
* cease transmission of video data.
*
* To save power when no video data is transmitted, a driver can power down
* the panel. This is the job of the .unprepare() function.
*
* Backlight can be handled automatically if configured using
* drm_panel_of_backlight(). Then the driver does not need to implement the
* functionality to enable/disable backlight.
*/
struct drm_panel_funcs {
/**
* @prepare:
*
* Turn on panel and perform set up.
*
* This function is optional.
*/
int (*prepare)(struct drm_panel *panel);
/**
* @enable:
*
* Enable panel (turn on back light, etc.).
*
* This function is optional.
*/
int (*enable)(struct drm_panel *panel);
/**
* @disable:
*
* Disable panel (turn off back light, etc.).
*
* This function is optional.
*/
int (*disable)(struct drm_panel *panel);
/**
* @unprepare:
*
* Turn off panel.
*
* This function is optional.
*/
int (*unprepare)(struct drm_panel *panel);
/**
* @get_modes:
*
* Add modes to the connector that the panel is attached to
* and returns the number of modes added.
*
* This function is mandatory.
*/
int (*get_modes)(struct drm_panel *panel,
struct drm_connector *connector);
/**
* @get_timings:
*
* Copy display timings into the provided array and return
* the number of display timings available.
*
* This function is optional.
*/
int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
struct display_timing *timings);
};
/**
* struct drm_panel - DRM panel object
*/
struct drm_panel {
/**
* @dev:
*
* Parent device of the panel.
*/
struct device *dev;
/**
* @backlight:
*
* Backlight device, used to turn on backlight after the call
* to enable(), and to turn off backlight before the call to
* disable().
* backlight is set by drm_panel_of_backlight() and drivers
* shall not assign it.
*/
struct backlight_device *backlight;
/**
* @funcs:
*
* Operations that can be performed on the panel.
*/
const struct drm_panel_funcs *funcs;
/**
* @connector_type:
*
* Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to
* initialise the drm_connector corresponding to the panel with the
* correct connector type.
*/
int connector_type;
/**
* @list:
*
* Panel entry in registry.
*/
struct list_head list;
};
void drm_panel_init(struct drm_panel *panel, struct device *dev,
const struct drm_panel_funcs *funcs,
int connector_type);
int drm_panel_add(struct drm_panel *panel);
void drm_panel_remove(struct drm_panel *panel);
int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector);
void drm_panel_detach(struct drm_panel *panel);
int drm_panel_prepare(struct drm_panel *panel);
int drm_panel_unprepare(struct drm_panel *panel);
int drm_panel_enable(struct drm_panel *panel);
int drm_panel_disable(struct drm_panel *panel);
int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
struct drm_panel *of_drm_find_panel(const struct device_node *np);
#else
static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
{
return ERR_PTR(-ENODEV);
}
#endif
#if IS_REACHABLE(CONFIG_BACKLIGHT_CLASS_DEVICE)
int drm_panel_of_backlight(struct drm_panel *panel);
#else
static inline int drm_panel_of_backlight(struct drm_panel *panel)
{
return 0;
}
#endif
#endif
|