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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#ifndef __DRM_PANEL_H__
25#define __DRM_PANEL_H__
26
27#include <linux/err.h>
28#include <linux/errno.h>
29#include <linux/list.h>
30
31struct backlight_device;
32struct dentry;
33struct device_node;
34struct drm_connector;
35struct drm_device;
36struct drm_panel;
37struct display_timing;
38
39enum drm_panel_orientation;
40
41/**
42 * struct drm_panel_funcs - perform operations on a given panel
43 *
44 * The .prepare() function is typically called before the display controller
45 * starts to transmit video data. Panel drivers can use this to turn the panel
46 * on and wait for it to become ready. If additional configuration is required
47 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
48 * to do that.
49 *
50 * After the display controller has started transmitting video data, it's safe
51 * to call the .enable() function. This will typically enable the backlight to
52 * make the image on screen visible. Some panels require a certain amount of
53 * time or frames before the image is displayed. This function is responsible
54 * for taking this into account before enabling the backlight to avoid visual
55 * glitches.
56 *
57 * Before stopping video transmission from the display controller it can be
58 * necessary to turn off the panel to avoid visual glitches. This is done in
59 * the .disable() function. Analogously to .enable() this typically involves
60 * turning off the backlight and waiting for some time to make sure no image
61 * is visible on the panel. It is then safe for the display controller to
62 * cease transmission of video data.
63 *
64 * To save power when no video data is transmitted, a driver can power down
65 * the panel. This is the job of the .unprepare() function.
66 *
67 * Backlight can be handled automatically if configured using
68 * drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver
69 * does not need to implement the functionality to enable/disable backlight.
70 */
71struct drm_panel_funcs {
72 /**
73 * @prepare:
74 *
75 * Turn on panel and perform set up.
76 *
77 * This function is optional.
78 */
79 int (*prepare)(struct drm_panel *panel);
80
81 /**
82 * @enable:
83 *
84 * Enable panel (turn on back light, etc.).
85 *
86 * This function is optional.
87 */
88 int (*enable)(struct drm_panel *panel);
89
90 /**
91 * @disable:
92 *
93 * Disable panel (turn off back light, etc.).
94 *
95 * This function is optional.
96 */
97 int (*disable)(struct drm_panel *panel);
98
99 /**
100 * @unprepare:
101 *
102 * Turn off panel.
103 *
104 * This function is optional.
105 */
106 int (*unprepare)(struct drm_panel *panel);
107
108 /**
109 * @get_modes:
110 *
111 * Add modes to the connector that the panel is attached to
112 * and returns the number of modes added.
113 *
114 * This function is mandatory.
115 */
116 int (*get_modes)(struct drm_panel *panel,
117 struct drm_connector *connector);
118
119 /**
120 * @get_orientation:
121 *
122 * Return the panel orientation set by device tree or EDID.
123 *
124 * This function is optional.
125 */
126 enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel);
127
128 /**
129 * @get_timings:
130 *
131 * Copy display timings into the provided array and return
132 * the number of display timings available.
133 *
134 * This function is optional.
135 */
136 int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
137 struct display_timing *timings);
138
139 /**
140 * @debugfs_init:
141 *
142 * Allows panels to create panels-specific debugfs files.
143 */
144 void (*debugfs_init)(struct drm_panel *panel, struct dentry *root);
145};
146
147/**
148 * struct drm_panel - DRM panel object
149 */
150struct drm_panel {
151 /**
152 * @dev:
153 *
154 * Parent device of the panel.
155 */
156 struct device *dev;
157
158 /**
159 * @backlight:
160 *
161 * Backlight device, used to turn on backlight after the call
162 * to enable(), and to turn off backlight before the call to
163 * disable().
164 * backlight is set by drm_panel_of_backlight() or
165 * drm_panel_dp_aux_backlight() and drivers shall not assign it.
166 */
167 struct backlight_device *backlight;
168
169 /**
170 * @funcs:
171 *
172 * Operations that can be performed on the panel.
173 */
174 const struct drm_panel_funcs *funcs;
175
176 /**
177 * @connector_type:
178 *
179 * Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to
180 * initialise the drm_connector corresponding to the panel with the
181 * correct connector type.
182 */
183 int connector_type;
184
185 /**
186 * @list:
187 *
188 * Panel entry in registry.
189 */
190 struct list_head list;
191};
192
193void drm_panel_init(struct drm_panel *panel, struct device *dev,
194 const struct drm_panel_funcs *funcs,
195 int connector_type);
196
197void drm_panel_add(struct drm_panel *panel);
198void drm_panel_remove(struct drm_panel *panel);
199
200int drm_panel_prepare(struct drm_panel *panel);
201int drm_panel_unprepare(struct drm_panel *panel);
202
203int drm_panel_enable(struct drm_panel *panel);
204int drm_panel_disable(struct drm_panel *panel);
205
206int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
207
208#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
209struct drm_panel *of_drm_find_panel(const struct device_node *np);
210int of_drm_get_panel_orientation(const struct device_node *np,
211 enum drm_panel_orientation *orientation);
212#else
213static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
214{
215 return ERR_PTR(-ENODEV);
216}
217
218static inline int of_drm_get_panel_orientation(const struct device_node *np,
219 enum drm_panel_orientation *orientation)
220{
221 return -ENODEV;
222}
223#endif
224
225#if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \
226 (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE)))
227int drm_panel_of_backlight(struct drm_panel *panel);
228#else
229static inline int drm_panel_of_backlight(struct drm_panel *panel)
230{
231 return 0;
232}
233#endif
234
235#endif
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#ifndef __DRM_PANEL_H__
25#define __DRM_PANEL_H__
26
27#include <linux/err.h>
28#include <linux/errno.h>
29#include <linux/list.h>
30
31struct backlight_device;
32struct device_node;
33struct drm_connector;
34struct drm_device;
35struct drm_panel;
36struct display_timing;
37
38/**
39 * struct drm_panel_funcs - perform operations on a given panel
40 *
41 * The .prepare() function is typically called before the display controller
42 * starts to transmit video data. Panel drivers can use this to turn the panel
43 * on and wait for it to become ready. If additional configuration is required
44 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
45 * to do that.
46 *
47 * After the display controller has started transmitting video data, it's safe
48 * to call the .enable() function. This will typically enable the backlight to
49 * make the image on screen visible. Some panels require a certain amount of
50 * time or frames before the image is displayed. This function is responsible
51 * for taking this into account before enabling the backlight to avoid visual
52 * glitches.
53 *
54 * Before stopping video transmission from the display controller it can be
55 * necessary to turn off the panel to avoid visual glitches. This is done in
56 * the .disable() function. Analogously to .enable() this typically involves
57 * turning off the backlight and waiting for some time to make sure no image
58 * is visible on the panel. It is then safe for the display controller to
59 * cease transmission of video data.
60 *
61 * To save power when no video data is transmitted, a driver can power down
62 * the panel. This is the job of the .unprepare() function.
63 *
64 * Backlight can be handled automatically if configured using
65 * drm_panel_of_backlight(). Then the driver does not need to implement the
66 * functionality to enable/disable backlight.
67 */
68struct drm_panel_funcs {
69 /**
70 * @prepare:
71 *
72 * Turn on panel and perform set up.
73 *
74 * This function is optional.
75 */
76 int (*prepare)(struct drm_panel *panel);
77
78 /**
79 * @enable:
80 *
81 * Enable panel (turn on back light, etc.).
82 *
83 * This function is optional.
84 */
85 int (*enable)(struct drm_panel *panel);
86
87 /**
88 * @disable:
89 *
90 * Disable panel (turn off back light, etc.).
91 *
92 * This function is optional.
93 */
94 int (*disable)(struct drm_panel *panel);
95
96 /**
97 * @unprepare:
98 *
99 * Turn off panel.
100 *
101 * This function is optional.
102 */
103 int (*unprepare)(struct drm_panel *panel);
104
105 /**
106 * @get_modes:
107 *
108 * Add modes to the connector that the panel is attached to
109 * and returns the number of modes added.
110 *
111 * This function is mandatory.
112 */
113 int (*get_modes)(struct drm_panel *panel,
114 struct drm_connector *connector);
115
116 /**
117 * @get_timings:
118 *
119 * Copy display timings into the provided array and return
120 * the number of display timings available.
121 *
122 * This function is optional.
123 */
124 int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
125 struct display_timing *timings);
126};
127
128/**
129 * struct drm_panel - DRM panel object
130 */
131struct drm_panel {
132 /**
133 * @dev:
134 *
135 * Parent device of the panel.
136 */
137 struct device *dev;
138
139 /**
140 * @backlight:
141 *
142 * Backlight device, used to turn on backlight after the call
143 * to enable(), and to turn off backlight before the call to
144 * disable().
145 * backlight is set by drm_panel_of_backlight() and drivers
146 * shall not assign it.
147 */
148 struct backlight_device *backlight;
149
150 /**
151 * @funcs:
152 *
153 * Operations that can be performed on the panel.
154 */
155 const struct drm_panel_funcs *funcs;
156
157 /**
158 * @connector_type:
159 *
160 * Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to
161 * initialise the drm_connector corresponding to the panel with the
162 * correct connector type.
163 */
164 int connector_type;
165
166 /**
167 * @list:
168 *
169 * Panel entry in registry.
170 */
171 struct list_head list;
172};
173
174void drm_panel_init(struct drm_panel *panel, struct device *dev,
175 const struct drm_panel_funcs *funcs,
176 int connector_type);
177
178int drm_panel_add(struct drm_panel *panel);
179void drm_panel_remove(struct drm_panel *panel);
180
181int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector);
182void drm_panel_detach(struct drm_panel *panel);
183
184int drm_panel_prepare(struct drm_panel *panel);
185int drm_panel_unprepare(struct drm_panel *panel);
186
187int drm_panel_enable(struct drm_panel *panel);
188int drm_panel_disable(struct drm_panel *panel);
189
190int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
191
192#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
193struct drm_panel *of_drm_find_panel(const struct device_node *np);
194#else
195static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
196{
197 return ERR_PTR(-ENODEV);
198}
199#endif
200
201#if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \
202 (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE)))
203int drm_panel_of_backlight(struct drm_panel *panel);
204#else
205static inline int drm_panel_of_backlight(struct drm_panel *panel)
206{
207 return 0;
208}
209#endif
210
211#endif