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 | #include <linux/mutex.h> |
31 | |
32 | struct backlight_device; |
33 | struct dentry; |
34 | struct device_node; |
35 | struct drm_connector; |
36 | struct drm_device; |
37 | struct drm_panel_follower; |
38 | struct drm_panel; |
39 | struct display_timing; |
40 | |
41 | enum drm_panel_orientation; |
42 | |
43 | /** |
44 | * struct drm_panel_funcs - perform operations on a given panel |
45 | * |
46 | * The .prepare() function is typically called before the display controller |
47 | * starts to transmit video data. Panel drivers can use this to turn the panel |
48 | * on and wait for it to become ready. If additional configuration is required |
49 | * (via a control bus such as I2C, SPI or DSI for example) this is a good time |
50 | * to do that. |
51 | * |
52 | * After the display controller has started transmitting video data, it's safe |
53 | * to call the .enable() function. This will typically enable the backlight to |
54 | * make the image on screen visible. Some panels require a certain amount of |
55 | * time or frames before the image is displayed. This function is responsible |
56 | * for taking this into account before enabling the backlight to avoid visual |
57 | * glitches. |
58 | * |
59 | * Before stopping video transmission from the display controller it can be |
60 | * necessary to turn off the panel to avoid visual glitches. This is done in |
61 | * the .disable() function. Analogously to .enable() this typically involves |
62 | * turning off the backlight and waiting for some time to make sure no image |
63 | * is visible on the panel. It is then safe for the display controller to |
64 | * cease transmission of video data. |
65 | * |
66 | * To save power when no video data is transmitted, a driver can power down |
67 | * the panel. This is the job of the .unprepare() function. |
68 | * |
69 | * Backlight can be handled automatically if configured using |
70 | * drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver |
71 | * does not need to implement the functionality to enable/disable backlight. |
72 | */ |
73 | struct drm_panel_funcs { |
74 | /** |
75 | * @prepare: |
76 | * |
77 | * Turn on panel and perform set up. |
78 | * |
79 | * This function is optional. |
80 | */ |
81 | int (*prepare)(struct drm_panel *panel); |
82 | |
83 | /** |
84 | * @enable: |
85 | * |
86 | * Enable panel (turn on back light, etc.). |
87 | * |
88 | * This function is optional. |
89 | */ |
90 | int (*enable)(struct drm_panel *panel); |
91 | |
92 | /** |
93 | * @disable: |
94 | * |
95 | * Disable panel (turn off back light, etc.). |
96 | * |
97 | * This function is optional. |
98 | */ |
99 | int (*disable)(struct drm_panel *panel); |
100 | |
101 | /** |
102 | * @unprepare: |
103 | * |
104 | * Turn off panel. |
105 | * |
106 | * This function is optional. |
107 | */ |
108 | int (*unprepare)(struct drm_panel *panel); |
109 | |
110 | /** |
111 | * @get_modes: |
112 | * |
113 | * Add modes to the connector that the panel is attached to |
114 | * and returns the number of modes added. |
115 | * |
116 | * This function is mandatory. |
117 | */ |
118 | int (*get_modes)(struct drm_panel *panel, |
119 | struct drm_connector *connector); |
120 | |
121 | /** |
122 | * @get_orientation: |
123 | * |
124 | * Return the panel orientation set by device tree or EDID. |
125 | * |
126 | * This function is optional. |
127 | */ |
128 | enum drm_panel_orientation (*get_orientation)(struct drm_panel *panel); |
129 | |
130 | /** |
131 | * @get_timings: |
132 | * |
133 | * Copy display timings into the provided array and return |
134 | * the number of display timings available. |
135 | * |
136 | * This function is optional. |
137 | */ |
138 | int (*get_timings)(struct drm_panel *panel, unsigned int num_timings, |
139 | struct display_timing *timings); |
140 | |
141 | /** |
142 | * @debugfs_init: |
143 | * |
144 | * Allows panels to create panels-specific debugfs files. |
145 | */ |
146 | void (*debugfs_init)(struct drm_panel *panel, struct dentry *root); |
147 | }; |
148 | |
149 | struct drm_panel_follower_funcs { |
150 | /** |
151 | * @panel_prepared: |
152 | * |
153 | * Called after the panel has been powered on. |
154 | */ |
155 | int (*panel_prepared)(struct drm_panel_follower *follower); |
156 | |
157 | /** |
158 | * @panel_unpreparing: |
159 | * |
160 | * Called before the panel is powered off. |
161 | */ |
162 | int (*panel_unpreparing)(struct drm_panel_follower *follower); |
163 | }; |
164 | |
165 | struct drm_panel_follower { |
166 | /** |
167 | * @funcs: |
168 | * |
169 | * Dependent device callbacks; should be initted by the caller. |
170 | */ |
171 | const struct drm_panel_follower_funcs *funcs; |
172 | |
173 | /** |
174 | * @list |
175 | * |
176 | * Used for linking into panel's list; set by drm_panel_add_follower(). |
177 | */ |
178 | struct list_head list; |
179 | |
180 | /** |
181 | * @panel |
182 | * |
183 | * The panel we're dependent on; set by drm_panel_add_follower(). |
184 | */ |
185 | struct drm_panel *panel; |
186 | }; |
187 | |
188 | /** |
189 | * struct drm_panel - DRM panel object |
190 | */ |
191 | struct drm_panel { |
192 | /** |
193 | * @dev: |
194 | * |
195 | * Parent device of the panel. |
196 | */ |
197 | struct device *dev; |
198 | |
199 | /** |
200 | * @backlight: |
201 | * |
202 | * Backlight device, used to turn on backlight after the call |
203 | * to enable(), and to turn off backlight before the call to |
204 | * disable(). |
205 | * backlight is set by drm_panel_of_backlight() or |
206 | * drm_panel_dp_aux_backlight() and drivers shall not assign it. |
207 | */ |
208 | struct backlight_device *backlight; |
209 | |
210 | /** |
211 | * @funcs: |
212 | * |
213 | * Operations that can be performed on the panel. |
214 | */ |
215 | const struct drm_panel_funcs *funcs; |
216 | |
217 | /** |
218 | * @connector_type: |
219 | * |
220 | * Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to |
221 | * initialise the drm_connector corresponding to the panel with the |
222 | * correct connector type. |
223 | */ |
224 | int connector_type; |
225 | |
226 | /** |
227 | * @list: |
228 | * |
229 | * Panel entry in registry. |
230 | */ |
231 | struct list_head list; |
232 | |
233 | /** |
234 | * @followers: |
235 | * |
236 | * A list of struct drm_panel_follower dependent on this panel. |
237 | */ |
238 | struct list_head followers; |
239 | |
240 | /** |
241 | * @follower_lock: |
242 | * |
243 | * Lock for followers list. |
244 | */ |
245 | struct mutex follower_lock; |
246 | |
247 | /** |
248 | * @prepare_prev_first: |
249 | * |
250 | * The previous controller should be prepared first, before the prepare |
251 | * for the panel is called. This is largely required for DSI panels |
252 | * where the DSI host controller should be initialised to LP-11 before |
253 | * the panel is powered up. |
254 | */ |
255 | bool prepare_prev_first; |
256 | |
257 | /** |
258 | * @prepared: |
259 | * |
260 | * If true then the panel has been prepared. |
261 | */ |
262 | bool prepared; |
263 | |
264 | /** |
265 | * @enabled: |
266 | * |
267 | * If true then the panel has been enabled. |
268 | */ |
269 | bool enabled; |
270 | }; |
271 | |
272 | void drm_panel_init(struct drm_panel *panel, struct device *dev, |
273 | const struct drm_panel_funcs *funcs, |
274 | int connector_type); |
275 | |
276 | void drm_panel_add(struct drm_panel *panel); |
277 | void drm_panel_remove(struct drm_panel *panel); |
278 | |
279 | int drm_panel_prepare(struct drm_panel *panel); |
280 | int drm_panel_unprepare(struct drm_panel *panel); |
281 | |
282 | int drm_panel_enable(struct drm_panel *panel); |
283 | int drm_panel_disable(struct drm_panel *panel); |
284 | |
285 | int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector); |
286 | |
287 | #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL) |
288 | struct drm_panel *of_drm_find_panel(const struct device_node *np); |
289 | int of_drm_get_panel_orientation(const struct device_node *np, |
290 | enum drm_panel_orientation *orientation); |
291 | #else |
292 | static inline struct drm_panel *of_drm_find_panel(const struct device_node *np) |
293 | { |
294 | return ERR_PTR(-ENODEV); |
295 | } |
296 | |
297 | static inline int of_drm_get_panel_orientation(const struct device_node *np, |
298 | enum drm_panel_orientation *orientation) |
299 | { |
300 | return -ENODEV; |
301 | } |
302 | #endif |
303 | |
304 | #if defined(CONFIG_DRM_PANEL) |
305 | bool drm_is_panel_follower(struct device *dev); |
306 | int drm_panel_add_follower(struct device *follower_dev, |
307 | struct drm_panel_follower *follower); |
308 | void drm_panel_remove_follower(struct drm_panel_follower *follower); |
309 | int devm_drm_panel_add_follower(struct device *follower_dev, |
310 | struct drm_panel_follower *follower); |
311 | #else |
312 | static inline bool drm_is_panel_follower(struct device *dev) |
313 | { |
314 | return false; |
315 | } |
316 | |
317 | static inline int drm_panel_add_follower(struct device *follower_dev, |
318 | struct drm_panel_follower *follower) |
319 | { |
320 | return -ENODEV; |
321 | } |
322 | |
323 | static inline void drm_panel_remove_follower(struct drm_panel_follower *follower) { } |
324 | static inline int devm_drm_panel_add_follower(struct device *follower_dev, |
325 | struct drm_panel_follower *follower) |
326 | { |
327 | return -ENODEV; |
328 | } |
329 | #endif |
330 | |
331 | #if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ |
332 | (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE))) |
333 | int drm_panel_of_backlight(struct drm_panel *panel); |
334 | #else |
335 | static inline int drm_panel_of_backlight(struct drm_panel *panel) |
336 | { |
337 | return 0; |
338 | } |
339 | #endif |
340 | |
341 | #endif |
342 | |