2 * Copyright (C) 2013, NVIDIA Corporation. All rights reserved.
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21 * DEALINGS IN THE SOFTWARE.
24 #ifndef __DRM_PANEL_H__
25 #define __DRM_PANEL_H__
27 #include <drm/drm_connector.h>
28 #include <linux/err.h>
29 #include <linux/errno.h>
30 #include <linux/list.h>
32 struct backlight_device;
37 struct display_timing;
40 * struct drm_panel_funcs - perform operations on a given panel
42 * The .prepare() function is typically called before the display controller
43 * starts to transmit video data. Panel drivers can use this to turn the panel
44 * on and wait for it to become ready. If additional configuration is required
45 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
48 * After the display controller has started transmitting video data, it's safe
49 * to call the .enable() function. This will typically enable the backlight to
50 * make the image on screen visible. Some panels require a certain amount of
51 * time or frames before the image is displayed. This function is responsible
52 * for taking this into account before enabling the backlight to avoid visual
55 * Before stopping video transmission from the display controller it can be
56 * necessary to turn off the panel to avoid visual glitches. This is done in
57 * the .disable() function. Analogously to .enable() this typically involves
58 * turning off the backlight and waiting for some time to make sure no image
59 * is visible on the panel. It is then safe for the display controller to
60 * cease transmission of video data.
62 * To save power when no video data is transmitted, a driver can power down
63 * the panel. This is the job of the .unprepare() function.
65 * Backlight can be handled automatically if configured using
66 * drm_panel_of_backlight() or drm_panel_dp_aux_backlight(). Then the driver
67 * does not need to implement the functionality to enable/disable backlight.
69 struct drm_panel_funcs {
73 * Turn on panel and perform set up.
75 * This function is optional.
77 int (*prepare)(struct drm_panel *panel);
82 * Enable panel (turn on back light, etc.).
84 * This function is optional.
86 int (*enable)(struct drm_panel *panel);
91 * Disable panel (turn off back light, etc.).
93 * This function is optional.
95 int (*disable)(struct drm_panel *panel);
102 * This function is optional.
104 int (*unprepare)(struct drm_panel *panel);
109 * Add modes to the connector that the panel is attached to
110 * and returns the number of modes added.
112 * This function is mandatory.
114 int (*get_modes)(struct drm_panel *panel,
115 struct drm_connector *connector);
120 * Copy display timings into the provided array and return
121 * the number of display timings available.
123 * This function is optional.
125 int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
126 struct display_timing *timings);
130 * struct drm_panel - DRM panel object
136 * Parent device of the panel.
143 * Backlight device, used to turn on backlight after the call
144 * to enable(), and to turn off backlight before the call to
146 * backlight is set by drm_panel_of_backlight() or
147 * drm_panel_dp_aux_backlight() and drivers shall not assign it.
149 struct backlight_device *backlight;
154 * Operations that can be performed on the panel.
156 const struct drm_panel_funcs *funcs;
161 * Type of the panel as a DRM_MODE_CONNECTOR_* value. This is used to
162 * initialise the drm_connector corresponding to the panel with the
163 * correct connector type.
170 * Panel orientation at initialisation. This is used to initialise the
171 * drm_connector property for panel orientation.
173 enum drm_panel_orientation orientation;
178 * Panel entry in registry.
180 struct list_head list;
183 * @prepare_upstream_first:
185 * The upstream controller should be prepared first, before the prepare
186 * for the panel is called. This is largely required for DSI panels
187 * where the DSI host controller should be initialised to LP-11 before
188 * the panel is powered up.
190 bool prepare_upstream_first;
193 void drm_panel_init(struct drm_panel *panel, struct device *dev,
194 const struct drm_panel_funcs *funcs,
197 void drm_panel_add(struct drm_panel *panel);
198 void drm_panel_remove(struct drm_panel *panel);
200 int drm_panel_prepare(struct drm_panel *panel);
201 int drm_panel_unprepare(struct drm_panel *panel);
203 int drm_panel_enable(struct drm_panel *panel);
204 int drm_panel_disable(struct drm_panel *panel);
206 int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
208 #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
209 struct drm_panel *of_drm_find_panel(const struct device_node *np);
210 int of_drm_get_panel_orientation(const struct device_node *np,
211 enum drm_panel_orientation *orientation);
213 static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
215 return ERR_PTR(-ENODEV);
218 static inline int of_drm_get_panel_orientation(const struct device_node *np,
219 enum drm_panel_orientation *orientation)
225 #if IS_ENABLED(CONFIG_DRM_PANEL) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \
226 (IS_MODULE(CONFIG_DRM) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE)))
227 int drm_panel_of_backlight(struct drm_panel *panel);
229 static inline int drm_panel_of_backlight(struct drm_panel *panel)