2 * Copyright (C) 2013, NVIDIA Corporation. All rights reserved.
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5 * copy of this software and associated documentation files (the "Software"),
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9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the
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15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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21 * DEALINGS IN THE SOFTWARE.
24 #ifndef __DRM_PANEL_H__
25 #define __DRM_PANEL_H__
27 #include <linux/err.h>
28 #include <linux/errno.h>
29 #include <linux/list.h>
35 struct display_timing;
38 * struct drm_panel_funcs - perform operations on a given panel
39 * @disable: disable panel (turn off back light, etc.)
40 * @unprepare: turn off panel
41 * @prepare: turn on panel and perform set up
42 * @enable: enable panel (turn on back light, etc.)
43 * @get_modes: add modes to the connector that the panel is attached to and
44 * return the number of modes added
45 * @get_timings: copy display timings into the provided array and return
46 * the number of display timings available
48 * The .prepare() function is typically called before the display controller
49 * starts to transmit video data. Panel drivers can use this to turn the panel
50 * on and wait for it to become ready. If additional configuration is required
51 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
54 * After the display controller has started transmitting video data, it's safe
55 * to call the .enable() function. This will typically enable the backlight to
56 * make the image on screen visible. Some panels require a certain amount of
57 * time or frames before the image is displayed. This function is responsible
58 * for taking this into account before enabling the backlight to avoid visual
61 * Before stopping video transmission from the display controller it can be
62 * necessary to turn off the panel to avoid visual glitches. This is done in
63 * the .disable() function. Analogously to .enable() this typically involves
64 * turning off the backlight and waiting for some time to make sure no image
65 * is visible on the panel. It is then safe for the display controller to
66 * cease transmission of video data.
68 * To save power when no video data is transmitted, a driver can power down
69 * the panel. This is the job of the .unprepare() function.
71 struct drm_panel_funcs {
72 int (*disable)(struct drm_panel *panel);
73 int (*unprepare)(struct drm_panel *panel);
74 int (*prepare)(struct drm_panel *panel);
75 int (*enable)(struct drm_panel *panel);
76 int (*get_modes)(struct drm_panel *panel);
77 int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
78 struct display_timing *timings);
82 * struct drm_panel - DRM panel object
83 * @drm: DRM device owning the panel
84 * @connector: DRM connector that the panel is attached to
85 * @dev: parent device of the panel
86 * @link: link from panel device (supplier) to DRM device (consumer)
87 * @funcs: operations that can be performed on the panel
88 * @list: panel entry in registry
91 struct drm_device *drm;
92 struct drm_connector *connector;
95 const struct drm_panel_funcs *funcs;
97 struct list_head list;
100 void drm_panel_init(struct drm_panel *panel);
102 int drm_panel_add(struct drm_panel *panel);
103 void drm_panel_remove(struct drm_panel *panel);
105 int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector);
106 int drm_panel_detach(struct drm_panel *panel);
108 int drm_panel_prepare(struct drm_panel *panel);
109 int drm_panel_unprepare(struct drm_panel *panel);
111 int drm_panel_enable(struct drm_panel *panel);
112 int drm_panel_disable(struct drm_panel *panel);
114 int drm_panel_get_modes(struct drm_panel *panel);
116 #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
117 struct drm_panel *of_drm_find_panel(const struct device_node *np);
119 static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
121 return ERR_PTR(-ENODEV);