xref: /linux/include/drm/drm_simple_kms_helper.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2016 Noralf Trønnes
4  */
5 
6 #ifndef __LINUX_DRM_SIMPLE_KMS_HELPER_H
7 #define __LINUX_DRM_SIMPLE_KMS_HELPER_H
8 
9 #include <drm/drm_crtc.h>
10 #include <drm/drm_encoder.h>
11 #include <drm/drm_plane.h>
12 
13 struct drm_simple_display_pipe;
14 
15 /**
16  * struct drm_simple_display_pipe_funcs - helper operations for a simple
17  *                                        display pipeline
18  */
19 struct drm_simple_display_pipe_funcs {
20 	/**
21 	 * @mode_valid:
22 	 *
23 	 * This callback is used to check if a specific mode is valid in the
24 	 * crtc used in this simple display pipe. This should be implemented
25 	 * if the display pipe has some sort of restriction in the modes
26 	 * it can display. For example, a given display pipe may be responsible
27 	 * to set a clock value. If the clock can not produce all the values
28 	 * for the available modes then this callback can be used to restrict
29 	 * the number of modes to only the ones that can be displayed. Another
30 	 * reason can be bandwidth mitigation: the memory port on the display
31 	 * controller can have bandwidth limitations not allowing pixel data
32 	 * to be fetched at any rate.
33 	 *
34 	 * This hook is used by the probe helpers to filter the mode list in
35 	 * drm_helper_probe_single_connector_modes(), and it is used by the
36 	 * atomic helpers to validate modes supplied by userspace in
37 	 * drm_atomic_helper_check_modeset().
38 	 *
39 	 * This function is optional.
40 	 *
41 	 * NOTE:
42 	 *
43 	 * Since this function is both called from the check phase of an atomic
44 	 * commit, and the mode validation in the probe paths it is not allowed
45 	 * to look at anything else but the passed-in mode, and validate it
46 	 * against configuration-invariant hardware constraints.
47 	 *
48 	 * RETURNS:
49 	 *
50 	 * drm_mode_status Enum
51 	 */
52 	enum drm_mode_status (*mode_valid)(struct drm_simple_display_pipe *pipe,
53 					   const struct drm_display_mode *mode);
54 
55 	/**
56 	 * @enable:
57 	 *
58 	 * This function should be used to enable the pipeline.
59 	 * It is called when the underlying crtc is enabled.
60 	 * This hook is optional.
61 	 */
62 	void (*enable)(struct drm_simple_display_pipe *pipe,
63 		       struct drm_crtc_state *crtc_state,
64 		       struct drm_plane_state *plane_state);
65 	/**
66 	 * @disable:
67 	 *
68 	 * This function should be used to disable the pipeline.
69 	 * It is called when the underlying crtc is disabled.
70 	 * This hook is optional.
71 	 */
72 	void (*disable)(struct drm_simple_display_pipe *pipe);
73 
74 	/**
75 	 * @check:
76 	 *
77 	 * This function is called in the check phase of an atomic update,
78 	 * specifically when the underlying plane is checked.
79 	 * The simple display pipeline helpers already check that the plane is
80 	 * not scaled, fills the entire visible area and is always enabled
81 	 * when the crtc is also enabled.
82 	 * This hook is optional.
83 	 *
84 	 * RETURNS:
85 	 *
86 	 * 0 on success, -EINVAL if the state or the transition can't be
87 	 * supported, -ENOMEM on memory allocation failure and -EDEADLK if an
88 	 * attempt to obtain another state object ran into a &drm_modeset_lock
89 	 * deadlock.
90 	 */
91 	int (*check)(struct drm_simple_display_pipe *pipe,
92 		     struct drm_plane_state *plane_state,
93 		     struct drm_crtc_state *crtc_state);
94 	/**
95 	 * @update:
96 	 *
97 	 * This function is called when the underlying plane state is updated.
98 	 * This hook is optional.
99 	 *
100 	 * This is the function drivers should submit the
101 	 * &drm_pending_vblank_event from. Using either
102 	 * drm_crtc_arm_vblank_event(), when the driver supports vblank
103 	 * interrupt handling, or drm_crtc_send_vblank_event() for more
104 	 * complex case. In case the hardware lacks vblank support entirely,
105 	 * drivers can set &struct drm_crtc_state.no_vblank in
106 	 * &struct drm_simple_display_pipe_funcs.check and let DRM's
107 	 * atomic helper fake a vblank event.
108 	 */
109 	void (*update)(struct drm_simple_display_pipe *pipe,
110 		       struct drm_plane_state *old_plane_state);
111 
112 	/**
113 	 * @prepare_fb:
114 	 *
115 	 * Optional, called by &drm_plane_helper_funcs.prepare_fb.  Please read
116 	 * the documentation for the &drm_plane_helper_funcs.prepare_fb hook for
117 	 * more details.
118 	 *
119 	 * For GEM drivers who neither have a @prepare_fb nor @cleanup_fb hook
120 	 * set, drm_gem_plane_helper_prepare_fb() is called automatically
121 	 * to implement this. Other drivers which need additional plane
122 	 * processing can call drm_gem_plane_helper_prepare_fb() from
123 	 * their @prepare_fb hook.
124 	 */
125 	int (*prepare_fb)(struct drm_simple_display_pipe *pipe,
126 			  struct drm_plane_state *plane_state);
127 
128 	/**
129 	 * @cleanup_fb:
130 	 *
131 	 * Optional, called by &drm_plane_helper_funcs.cleanup_fb.  Please read
132 	 * the documentation for the &drm_plane_helper_funcs.cleanup_fb hook for
133 	 * more details.
134 	 */
135 	void (*cleanup_fb)(struct drm_simple_display_pipe *pipe,
136 			   struct drm_plane_state *plane_state);
137 
138 	/**
139 	 * @begin_fb_access:
140 	 *
141 	 * Optional, called by &drm_plane_helper_funcs.begin_fb_access. Please read
142 	 * the documentation for the &drm_plane_helper_funcs.begin_fb_access hook for
143 	 * more details.
144 	 */
145 	int (*begin_fb_access)(struct drm_simple_display_pipe *pipe,
146 			       struct drm_plane_state *new_plane_state);
147 
148 	/**
149 	 * @end_fb_access:
150 	 *
151 	 * Optional, called by &drm_plane_helper_funcs.end_fb_access. Please read
152 	 * the documentation for the &drm_plane_helper_funcs.end_fb_access hook for
153 	 * more details.
154 	 */
155 	void (*end_fb_access)(struct drm_simple_display_pipe *pipe,
156 			      struct drm_plane_state *plane_state);
157 
158 	/**
159 	 * @enable_vblank:
160 	 *
161 	 * Optional, called by &drm_crtc_funcs.enable_vblank. Please read
162 	 * the documentation for the &drm_crtc_funcs.enable_vblank hook for
163 	 * more details.
164 	 */
165 	int (*enable_vblank)(struct drm_simple_display_pipe *pipe);
166 
167 	/**
168 	 * @disable_vblank:
169 	 *
170 	 * Optional, called by &drm_crtc_funcs.disable_vblank. Please read
171 	 * the documentation for the &drm_crtc_funcs.disable_vblank hook for
172 	 * more details.
173 	 */
174 	void (*disable_vblank)(struct drm_simple_display_pipe *pipe);
175 
176 	/**
177 	 * @reset_crtc:
178 	 *
179 	 * Optional, called by &drm_crtc_funcs.reset. Please read the
180 	 * documentation for the &drm_crtc_funcs.reset hook for more details.
181 	 */
182 	void (*reset_crtc)(struct drm_simple_display_pipe *pipe);
183 
184 	/**
185 	 * @duplicate_crtc_state:
186 	 *
187 	 * Optional, called by &drm_crtc_funcs.atomic_duplicate_state. Please
188 	 * read the documentation for the &drm_crtc_funcs.atomic_duplicate_state
189 	 * hook for more details.
190 	 */
191 	struct drm_crtc_state * (*duplicate_crtc_state)(struct drm_simple_display_pipe *pipe);
192 
193 	/**
194 	 * @destroy_crtc_state:
195 	 *
196 	 * Optional, called by &drm_crtc_funcs.atomic_destroy_state. Please
197 	 * read the documentation for the &drm_crtc_funcs.atomic_destroy_state
198 	 * hook for more details.
199 	 */
200 	void (*destroy_crtc_state)(struct drm_simple_display_pipe *pipe,
201 				   struct drm_crtc_state *crtc_state);
202 
203 	/**
204 	 * @reset_plane:
205 	 *
206 	 * Optional, called by &drm_plane_funcs.reset. Please read the
207 	 * documentation for the &drm_plane_funcs.reset hook for more details.
208 	 */
209 	void (*reset_plane)(struct drm_simple_display_pipe *pipe);
210 
211 	/**
212 	 * @duplicate_plane_state:
213 	 *
214 	 * Optional, called by &drm_plane_funcs.atomic_duplicate_state.  Please
215 	 * read the documentation for the &drm_plane_funcs.atomic_duplicate_state
216 	 * hook for more details.
217 	 */
218 	struct drm_plane_state * (*duplicate_plane_state)(struct drm_simple_display_pipe *pipe);
219 
220 	/**
221 	 * @destroy_plane_state:
222 	 *
223 	 * Optional, called by &drm_plane_funcs.atomic_destroy_state.  Please
224 	 * read the documentation for the &drm_plane_funcs.atomic_destroy_state
225 	 * hook for more details.
226 	 */
227 	void (*destroy_plane_state)(struct drm_simple_display_pipe *pipe,
228 				    struct drm_plane_state *plane_state);
229 };
230 
231 /**
232  * struct drm_simple_display_pipe - simple display pipeline
233  * @crtc: CRTC control structure
234  * @plane: Plane control structure
235  * @encoder: Encoder control structure
236  * @connector: Connector control structure
237  * @funcs: Pipeline control functions (optional)
238  *
239  * Simple display pipeline with plane, crtc and encoder collapsed into one
240  * entity. It should be initialized by calling drm_simple_display_pipe_init().
241  */
242 struct drm_simple_display_pipe {
243 	struct drm_crtc crtc;
244 	struct drm_plane plane;
245 	struct drm_encoder encoder;
246 	struct drm_connector *connector;
247 
248 	const struct drm_simple_display_pipe_funcs *funcs;
249 };
250 
251 int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe *pipe,
252 					  struct drm_bridge *bridge);
253 
254 int drm_simple_display_pipe_init(struct drm_device *dev,
255 			struct drm_simple_display_pipe *pipe,
256 			const struct drm_simple_display_pipe_funcs *funcs,
257 			const uint32_t *formats, unsigned int format_count,
258 			const uint64_t *format_modifiers,
259 			struct drm_connector *connector);
260 
261 int drm_simple_encoder_init(struct drm_device *dev,
262 			    struct drm_encoder *encoder,
263 			    int encoder_type);
264 
265 void *__drmm_simple_encoder_alloc(struct drm_device *dev, size_t size,
266 				  size_t offset, int encoder_type);
267 
268 /**
269  * drmm_simple_encoder_alloc - Allocate and initialize an encoder with basic
270  *                             functionality.
271  * @dev: drm device
272  * @type: the type of the struct which contains struct &drm_encoder
273  * @member: the name of the &drm_encoder within @type.
274  * @encoder_type: user visible type of the encoder
275  *
276  * Allocates and initializes an encoder that has no further functionality.
277  * Settings for possible CRTC and clones are left to their initial values.
278  * Cleanup is automatically handled through registering drm_encoder_cleanup()
279  * with drmm_add_action().
280  *
281  * Returns:
282  * Pointer to new encoder, or ERR_PTR on failure.
283  */
284 #define drmm_simple_encoder_alloc(dev, type, member, encoder_type) \
285 	((type *)__drmm_simple_encoder_alloc(dev, sizeof(type), \
286 					     offsetof(type, member), \
287 					     encoder_type))
288 
289 #endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */
290