1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Copyright (C) 2017 Icenowy Zheng <icenowy@aosc.io>
4 */
5
6 #ifndef _SUNXI_ENGINE_H_
7 #define _SUNXI_ENGINE_H_
8
9 struct drm_plane;
10 struct drm_device;
11 struct drm_crtc_state;
12
13 struct sunxi_engine;
14
15 /**
16 * struct sunxi_engine_ops - helper operations for sunXi engines
17 *
18 * These hooks are used by the common part of the DRM driver to
19 * implement the proper behaviour.
20 */
21 struct sunxi_engine_ops {
22 /**
23 * @atomic_begin:
24 *
25 * This callback allows to prepare our engine for an atomic
26 * update. This is mirroring the
27 * &drm_crtc_helper_funcs.atomic_begin callback, so any
28 * documentation there applies.
29 *
30 * This function is optional.
31 */
32 void (*atomic_begin)(struct sunxi_engine *engine,
33 struct drm_crtc_state *old_state);
34
35 /**
36 * @atomic_check:
37 *
38 * This callback allows to validate plane-update related CRTC
39 * constraints specific to engines. This is mirroring the
40 * &drm_crtc_helper_funcs.atomic_check callback, so any
41 * documentation there applies.
42 *
43 * This function is optional.
44 *
45 * RETURNS:
46 *
47 * 0 on success or a negative error code.
48 */
49 int (*atomic_check)(struct sunxi_engine *engine,
50 struct drm_crtc_state *state);
51
52 /**
53 * @commit:
54 *
55 * This callback will trigger the hardware switch to commit
56 * the new configuration that has been setup during the next
57 * vblank period.
58 *
59 * This function is optional.
60 */
61 void (*commit)(struct sunxi_engine *engine);
62
63 /**
64 * @layers_init:
65 *
66 * This callback is used to allocate, initialize and register
67 * the layers supported by that engine.
68 *
69 * This function is mandatory.
70 *
71 * RETURNS:
72 *
73 * The array of struct drm_plane backing the layers, or an
74 * error pointer on failure.
75 */
76 struct drm_plane **(*layers_init)(struct drm_device *drm,
77 struct sunxi_engine *engine);
78
79 /**
80 * @apply_color_correction:
81 *
82 * This callback will enable the color correction in the
83 * engine. This is useful only for the composite output.
84 *
85 * This function is optional.
86 */
87 void (*apply_color_correction)(struct sunxi_engine *engine);
88
89 /**
90 * @disable_color_correction:
91 *
92 * This callback will stop the color correction in the
93 * engine. This is useful only for the composite output.
94 *
95 * This function is optional.
96 */
97 void (*disable_color_correction)(struct sunxi_engine *engine);
98
99 /**
100 * @vblank_quirk:
101 *
102 * This callback is used to implement engine-specific
103 * behaviour part of the VBLANK event. It is run with all the
104 * constraints of an interrupt (can't sleep, all local
105 * interrupts disabled) and therefore should be as fast as
106 * possible.
107 *
108 * This function is optional.
109 */
110 void (*vblank_quirk)(struct sunxi_engine *engine);
111 };
112
113 /**
114 * struct sunxi_engine - the common parts of an engine for sun4i-drm driver
115 * @ops: the operations of the engine
116 * @node: the of device node of the engine
117 * @regs: the regmap of the engine
118 * @id: the id of the engine (-1 if not used)
119 */
120 struct sunxi_engine {
121 const struct sunxi_engine_ops *ops;
122
123 struct device_node *node;
124 struct regmap *regs;
125
126 int id;
127
128 /* Engine list management */
129 struct list_head list;
130 };
131
132 /**
133 * sunxi_engine_commit() - commit all changes of the engine
134 * @engine: pointer to the engine
135 */
136 static inline void
137 sunxi_engine_commit(struct sunxi_engine *engine)
138 {
139 if (engine->ops && engine->ops->commit)
140 engine->ops->commit(engine);
141 }
142
143 /**
144 * sunxi_engine_layers_init() - Create planes (layers) for the engine
145 * @drm: pointer to the drm_device for which planes will be created
146 * @engine: pointer to the engine
147 */
148 static inline struct drm_plane **
149 sunxi_engine_layers_init(struct drm_device *drm, struct sunxi_engine *engine)
150 {
151 if (engine->ops && engine->ops->layers_init)
152 return engine->ops->layers_init(drm, engine);
153 return ERR_PTR(-ENOSYS);
154 }
155
156 /**
157 * sunxi_engine_apply_color_correction - Apply the RGB2YUV color correction
158 * @engine: pointer to the engine
159 *
160 * This functionality is optional for an engine, however, if the engine is
161 * intended to be used with TV Encoder, the output will be incorrect
162 * without the color correction, due to TV Encoder expects the engine to
163 * output directly YUV signal.
164 */
165 static inline void
166 sunxi_engine_apply_color_correction(struct sunxi_engine *engine)
167 {
168 if (engine->ops && engine->ops->apply_color_correction)
169 engine->ops->apply_color_correction(engine);
170 }
171
172 /**
173 * sunxi_engine_disable_color_correction - Disable the color space correction
174 * @engine: pointer to the engine
175 *
176 * This function is paired with apply_color_correction().
177 */
178 static inline void
179 sunxi_engine_disable_color_correction(struct sunxi_engine *engine)
180 {
181 if (engine->ops && engine->ops->disable_color_correction)
182 engine->ops->disable_color_correction(engine);
183 }
184 #endif /* _SUNXI_ENGINE_H_ */