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 device_node;
 32struct drm_connector;
 33struct drm_device;
 
 34struct drm_panel;
 35struct display_timing;
 36
 
 
 37/**
 38 * struct drm_panel_funcs - perform operations on a given panel
 39 *
 40 * The .prepare() function is typically called before the display controller
 41 * starts to transmit video data. Panel drivers can use this to turn the panel
 42 * on and wait for it to become ready. If additional configuration is required
 43 * (via a control bus such as I2C, SPI or DSI for example) this is a good time
 44 * to do that.
 45 *
 46 * After the display controller has started transmitting video data, it's safe
 47 * to call the .enable() function. This will typically enable the backlight to
 48 * make the image on screen visible. Some panels require a certain amount of
 49 * time or frames before the image is displayed. This function is responsible
 50 * for taking this into account before enabling the backlight to avoid visual
 51 * glitches.
 52 *
 53 * Before stopping video transmission from the display controller it can be
 54 * necessary to turn off the panel to avoid visual glitches. This is done in
 55 * the .disable() function. Analogously to .enable() this typically involves
 56 * turning off the backlight and waiting for some time to make sure no image
 57 * is visible on the panel. It is then safe for the display controller to
 58 * cease transmission of video data.
 59 *
 60 * To save power when no video data is transmitted, a driver can power down
 61 * the panel. This is the job of the .unprepare() function.
 
 
 
 
 62 */
 63struct drm_panel_funcs {
 64	/**
 65	 * @prepare:
 66	 *
 67	 * Turn on panel and perform set up.
 
 
 68	 */
 69	int (*prepare)(struct drm_panel *panel);
 70
 71	/**
 72	 * @enable:
 73	 *
 74	 * Enable panel (turn on back light, etc.).
 
 
 75	 */
 76	int (*enable)(struct drm_panel *panel);
 77
 78	/**
 79	 * @disable:
 80	 *
 81	 * Disable panel (turn off back light, etc.).
 
 
 82	 */
 83	int (*disable)(struct drm_panel *panel);
 84
 85	/**
 86	 * @unprepare:
 87	 *
 88	 * Turn off panel.
 
 
 89	 */
 90	int (*unprepare)(struct drm_panel *panel);
 91
 92	/**
 93	 * @get_modes:
 94	 *
 95	 * Add modes to the connector that the panel is attached to and
 96	 * return the number of modes added.
 
 
 
 
 
 
 
 
 
 
 
 
 97	 */
 98	int (*get_modes)(struct drm_panel *panel);
 99
100	/**
101	 * @get_timings:
102	 *
103	 * Copy display timings into the provided array and return
104	 * the number of display timings available.
 
 
105	 */
106	int (*get_timings)(struct drm_panel *panel, unsigned int num_timings,
107			   struct display_timing *timings);
 
 
 
 
 
 
 
108};
109
110/**
111 * struct drm_panel - DRM panel object
112 */
113struct drm_panel {
 
 
 
 
 
 
 
 
 
 
 
 
 
114	/**
115	 * @drm:
 
 
 
 
 
 
 
116	 *
117	 * DRM device owning the panel.
118	 */
119	struct drm_device *drm;
120
121	/**
122	 * @connector:
123	 *
124	 * DRM connector that the panel is attached to.
125	 */
126	struct drm_connector *connector;
 
127
 
 
 
 
128	/**
129	 * @dev:
130	 *
131	 * Parent device of the panel.
132	 */
133	struct device *dev;
134
135	/**
 
 
 
 
 
 
 
 
 
 
 
136	 * @funcs:
137	 *
138	 * Operations that can be performed on the panel.
139	 */
140	const struct drm_panel_funcs *funcs;
141
142	/**
 
 
 
 
 
 
 
 
 
143	 * @list:
144	 *
145	 * Panel entry in registry.
146	 */
147	struct list_head list;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
148};
149
150void drm_panel_init(struct drm_panel *panel);
 
 
151
152int drm_panel_add(struct drm_panel *panel);
153void drm_panel_remove(struct drm_panel *panel);
154
155int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector);
156void drm_panel_detach(struct drm_panel *panel);
157
158int drm_panel_prepare(struct drm_panel *panel);
159int drm_panel_unprepare(struct drm_panel *panel);
160
161int drm_panel_enable(struct drm_panel *panel);
162int drm_panel_disable(struct drm_panel *panel);
163
164int drm_panel_get_modes(struct drm_panel *panel);
165
166#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
167struct drm_panel *of_drm_find_panel(const struct device_node *np);
 
 
168#else
169static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
170{
171	return ERR_PTR(-ENODEV);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
172}
173#endif
174
175#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#include <linux/mutex.h>
 31
 32struct backlight_device;
 33struct dentry;
 34struct device_node;
 35struct drm_connector;
 36struct drm_device;
 37struct drm_panel_follower;
 38struct drm_panel;
 39struct display_timing;
 40
 41enum 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 */
 73struct 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
149struct 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
165struct 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 */
191struct 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
272void drm_panel_init(struct drm_panel *panel, struct device *dev,
273		    const struct drm_panel_funcs *funcs,
274		    int connector_type);
275
276void drm_panel_add(struct drm_panel *panel);
277void drm_panel_remove(struct drm_panel *panel);
278
 
 
 
279int drm_panel_prepare(struct drm_panel *panel);
280int drm_panel_unprepare(struct drm_panel *panel);
281
282int drm_panel_enable(struct drm_panel *panel);
283int drm_panel_disable(struct drm_panel *panel);
284
285int drm_panel_get_modes(struct drm_panel *panel, struct drm_connector *connector);
286
287#if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
288struct drm_panel *of_drm_find_panel(const struct device_node *np);
289int of_drm_get_panel_orientation(const struct device_node *np,
290				 enum drm_panel_orientation *orientation);
291#else
292static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
293{
294	return ERR_PTR(-ENODEV);
295}
296
297static 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)
305bool drm_is_panel_follower(struct device *dev);
306int drm_panel_add_follower(struct device *follower_dev,
307			   struct drm_panel_follower *follower);
308void drm_panel_remove_follower(struct drm_panel_follower *follower);
309int devm_drm_panel_add_follower(struct device *follower_dev,
310				struct drm_panel_follower *follower);
311#else
312static inline bool drm_is_panel_follower(struct device *dev)
313{
314	return false;
315}
316
317static inline int drm_panel_add_follower(struct device *follower_dev,
318					 struct drm_panel_follower *follower)
319{
320	return -ENODEV;
321}
322
323static inline void drm_panel_remove_follower(struct drm_panel_follower *follower) { }
324static 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)))
333int drm_panel_of_backlight(struct drm_panel *panel);
334#else
335static inline int drm_panel_of_backlight(struct drm_panel *panel)
336{
337	return 0;
338}
339#endif
340
341#endif