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
13struct drm_simple_display_pipe;
14
15/**
16 * struct drm_simple_display_pipe_funcs - helper operations for a simple
17 * display pipeline
18 */
19struct 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 */
242struct 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
251int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe *pipe,
252 struct drm_bridge *bridge);
253
254int 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
261int drm_simple_encoder_init(struct drm_device *dev,
262 struct drm_encoder *encoder,
263 int encoder_type);
264
265void *__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